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* [PATCH V9 0/9] vDPA support
@ 2020-03-26 14:01 Jason Wang
  2020-03-26 14:01 ` [PATCH V9 1/9] vhost: refine vhost and vringh kconfig Jason Wang
                   ` (9 more replies)
  0 siblings, 10 replies; 38+ messages in thread
From: Jason Wang @ 2020-03-26 14:01 UTC (permalink / raw)
  To: mst, linux-kernel, kvm, virtualization, netdev
  Cc: jgg, maxime.coquelin, cunming.liang, zhihong.wang, rob.miller,
	xiao.w.wang, lingshan.zhu, eperezma, lulu, parav, kevin.tian,
	stefanha, rdunlap, hch, aadam, jiri, shahafs, hanand, mhabets,
	gdawar, saugatm, vmireyno, zhangweining, Jason Wang

Hi all:

This is an update version of vDPA support in kernel.

vDPA device is a device that uses a datapath which complies with the
virtio specifications with vendor specific control path. vDPA devices
can be both physically located on the hardware or emulated by
software. vDPA hardware devices are usually implemented through PCIE
with the following types:

- PF (Physical Function) - A single Physical Function
- VF (Virtual Function) - Device that supports single root I/O
  virtualization (SR-IOV). Its Virtual Function (VF) represents a
  virtualized instance of the device that can be assigned to different
  partitions
- ADI (Assignable Device Interface) and its equivalents - With
  technologies such as Intel Scalable IOV, a virtual device (VDEV)
  composed by host OS utilizing one or more ADIs. Or its equivalent
  like SF (Sub function) from Mellanox.

From a driver's perspective, depends on how and where the DMA
translation is done, vDPA devices are split into two types:

- Platform specific DMA translation - From the driver's perspective,
  the device can be used on a platform where device access to data in
  memory is limited and/or translated. An example is a PCIE vDPA whose
  DMA request was tagged via a bus (e.g PCIE) specific way. DMA
  translation and protection are done at PCIE bus IOMMU level.
- Device specific DMA translation - The device implements DMA
  isolation and protection through its own logic. An example is a vDPA
  device which uses on-chip IOMMU.

To hide the differences and complexity of the above types for a vDPA
device/IOMMU options and in order to present a generic virtio device
to the upper layer, a device agnostic framework is required.

This series introduces a software vDPA bus which abstracts the
common attributes of vDPA device, vDPA bus driver and the
communication method, the bus operations (vdpa_config_ops) between the
vDPA device abstraction and the vDPA bus driver. This allows multiple
types of drivers to be used for vDPA device like the virtio_vdpa and
vhost_vdpa driver to operate on the bus and allow vDPA device could be
used by either kernel virtio driver or userspace vhost drivers as:

   virtio drivers  vhost drivers
          |             |
    [virtio bus]   [vhost uAPI]
          |             |
   virtio device   vhost device
   virtio_vdpa drv vhost_vdpa drv
             \       /
            [vDPA bus]
                 |
            vDPA device
            hardware drv
                 |
            [hardware bus]
                 |
            vDPA hardware

virtio_vdpa driver is a transport implementation for kernel virtio
drivers on top of vDPA bus operations. An alternative is to refactor
virtio bus which is sub-optimal since the bus and drivers are designed
to be use by kernel subsystem, a non-trivial major refactoring is
needed which may impact a brunches of drivers and devices
implementation inside the kernel. Using a new transport may grealy
simply both the design and changes.

vhost_vdpa driver is a new type of vhost device which allows userspace
vhost drivers to use vDPA devices via vhost uAPI (with minor
extension). This help to minimize the changes of existed vhost drivers
for using vDPA devices.

With the abstraction of vDPA bus and vDPA bus operations, the
difference and complexity of the under layer hardware is hidden from
upper layer. The vDPA bus drivers on top can use a unified
vdpa_config_ops to control different types of vDPA device.

Two drivers were implemented with the framework introduced in this
series:

- Intel IFC VF driver which depends on the platform IOMMU for DMA
  translation
- VDPA simulator which is a software test device with an emulated
  onchip IOMMU

Future work:

- direct doorbell mapping support
- control virtqueue support
- dirty page tracking support
- direct interrupt support
- management API (devlink)

Please review.

Thanks

Changes from V8:

- switch to use devres for PCI resoureces of IFCVF (Jason)
- require the caller of vdap_alloc_device() to use "struct foo"
  instead of foo (Jason)
- some tweaks on the IFCVF driver

Changes from V7:

- refine kconfig to solve the dependency issues on archs that lacks of
  CONFIG_VIRTUALIZATION (kbuild)

Changes from V6:

- vdpa_alloc_device() will allocate parent strcture (Jason)
- remove the vdpa core dev info in IFCVF patch (Jason)
- provide a free method in the vdpa bus operations for drivet to free
  private data
- switch to use new layout in vdapsim and IFCVF
- make IFCVF depends on PCI_MSI (kbuild)
- some tweaks on the IFCVF driver

Changes from V5:

- include Intel IFCVF driver and vhost-vdpa drivers
- add the platform IOMMU support for vhost-vdpa
- check the return value of dev_set_name() (Jason)
- various tweaks and fixes

Changes from V4:

- use put_device() instead of kfree when fail to register virtio
  device (Jason)
- simplify the error handling when allocating vdpasim device (Jason)
- don't use device_for_each_child() during module exit (Jason)
- correct the error checking for vdpa_alloc_device() (Harpreet, Lingshan)

Changes from V3:

- various Kconfig fixes (Randy)

Changes from V2:

- release idr in the release function for put_device() unwind (Jason)
- don't panic when fail to register vdpa bus (Jason)
- use unsigned int instead of int for ida (Jason)
- fix the wrong commit log in virito_vdpa patches (Jason)
- make vdpa_sim depends on RUNTIME_TESTING_MENU (Michael)
- provide a bus release function for vDPA device (Jason)
- fix the wrong unwind when creating devices for vDPA simulator (Jason)
- move vDPA simulator to a dedicated directory (Lingshan)
- cancel the work before release vDPA simulator

Changes from V1:

- drop sysfs API, leave the management interface to future development
  (Michael)
- introduce incremental DMA ops (dma_map/dma_unmap) (Michael)
- introduce dma_device and use it instead of parent device for doing
  IOMMU or DMA from bus driver (Michael, Jason, Ling Shan, Tiwei)
- accept parent device and dma device when register vdpa device
- coding style and compile fixes (Randy)
- using vdpa_xxx instead of xxx_vdpa (Jason)
- ove vDPA accessors to header and make it static inline (Jason)
- split vdp_register_device() into two helpers vdpa_init_device() and
  vdpa_register_device() which allows intermediate step to be done (Jason)
- warn on invalidate queue state when fail to creating virtqueue (Jason)
- make to_virtio_vdpa_device() static (Jason)
- use kmalloc/kfree instead of devres for virtio vdpa device (Jason)
- avoid using cast in vdpa bus function (Jason)
- introduce module_vdpa_driver and fix module refcnt (Jason)
- fix returning freed address in vdapsim coherent DMA addr allocation (Dan)
- various other fixes and tweaks

V8: https://lkml.org/lkml/2020/3/25/125
V7: https://lkml.org/lkml/2020/3/24/21
V6: https://lkml.org/lkml/2020/3/18/88
V5: https://lkml.org/lkml/2020/2/26/58
V4: https://lkml.org/lkml/2020/2/20/59
V3: https://lkml.org/lkml/2020/2/19/1347
V2: https://lkml.org/lkml/2020/2/9/275
V1: https://lkml.org/lkml/2020/1/16/353

Jason Wang (7):
  vhost: refine vhost and vringh kconfig
  vhost: allow per device message handler
  vhost: factor out IOTLB
  vringh: IOTLB support
  vDPA: introduce vDPA bus
  virtio: introduce a vDPA based transport
  vdpasim: vDPA device simulator

Tiwei Bie (1):
  vhost: introduce vDPA-based backend

Zhu Lingshan (1):
  virtio: Intel IFC VF driver for VDPA

 MAINTAINERS                             |   2 +
 arch/arm/kvm/Kconfig                    |   2 -
 arch/arm64/kvm/Kconfig                  |   2 -
 arch/mips/kvm/Kconfig                   |   2 -
 arch/powerpc/kvm/Kconfig                |   2 -
 arch/s390/kvm/Kconfig                   |   4 -
 arch/x86/kvm/Kconfig                    |   4 -
 drivers/Kconfig                         |   2 +
 drivers/misc/mic/Kconfig                |   4 -
 drivers/net/caif/Kconfig                |   4 -
 drivers/vhost/Kconfig                   |  42 +-
 drivers/vhost/Kconfig.vringh            |   6 -
 drivers/vhost/Makefile                  |   6 +
 drivers/vhost/iotlb.c                   | 177 +++++
 drivers/vhost/net.c                     |   5 +-
 drivers/vhost/scsi.c                    |   2 +-
 drivers/vhost/vdpa.c                    | 883 ++++++++++++++++++++++++
 drivers/vhost/vhost.c                   | 233 +++----
 drivers/vhost/vhost.h                   |  45 +-
 drivers/vhost/vringh.c                  | 421 ++++++++++-
 drivers/vhost/vsock.c                   |   2 +-
 drivers/virtio/Kconfig                  |  15 +
 drivers/virtio/Makefile                 |   2 +
 drivers/virtio/vdpa/Kconfig             |  37 +
 drivers/virtio/vdpa/Makefile            |   4 +
 drivers/virtio/vdpa/ifcvf/Makefile      |   3 +
 drivers/virtio/vdpa/ifcvf/ifcvf_base.c  | 389 +++++++++++
 drivers/virtio/vdpa/ifcvf/ifcvf_base.h  | 118 ++++
 drivers/virtio/vdpa/ifcvf/ifcvf_main.c  | 435 ++++++++++++
 drivers/virtio/vdpa/vdpa.c              | 180 +++++
 drivers/virtio/vdpa/vdpa_sim/Makefile   |   2 +
 drivers/virtio/vdpa/vdpa_sim/vdpa_sim.c | 629 +++++++++++++++++
 drivers/virtio/virtio_vdpa.c            | 396 +++++++++++
 include/linux/vdpa.h                    | 253 +++++++
 include/linux/vhost_iotlb.h             |  47 ++
 include/linux/vringh.h                  |  36 +
 include/uapi/linux/vhost.h              |  24 +
 include/uapi/linux/vhost_types.h        |   8 +
 38 files changed, 4180 insertions(+), 248 deletions(-)
 delete mode 100644 drivers/vhost/Kconfig.vringh
 create mode 100644 drivers/vhost/iotlb.c
 create mode 100644 drivers/vhost/vdpa.c
 create mode 100644 drivers/virtio/vdpa/Kconfig
 create mode 100644 drivers/virtio/vdpa/Makefile
 create mode 100644 drivers/virtio/vdpa/ifcvf/Makefile
 create mode 100644 drivers/virtio/vdpa/ifcvf/ifcvf_base.c
 create mode 100644 drivers/virtio/vdpa/ifcvf/ifcvf_base.h
 create mode 100644 drivers/virtio/vdpa/ifcvf/ifcvf_main.c
 create mode 100644 drivers/virtio/vdpa/vdpa.c
 create mode 100644 drivers/virtio/vdpa/vdpa_sim/Makefile
 create mode 100644 drivers/virtio/vdpa/vdpa_sim/vdpa_sim.c
 create mode 100644 drivers/virtio/virtio_vdpa.c
 create mode 100644 include/linux/vdpa.h
 create mode 100644 include/linux/vhost_iotlb.h

-- 
2.20.1


^ permalink raw reply	[flat|nested] 38+ messages in thread

* [PATCH V9 1/9] vhost: refine vhost and vringh kconfig
  2020-03-26 14:01 [PATCH V9 0/9] vDPA support Jason Wang
@ 2020-03-26 14:01 ` Jason Wang
  2020-04-01 11:21   ` Christian Borntraeger
  2020-04-01 13:22   ` Michael S. Tsirkin
  2020-03-26 14:01 ` [PATCH V9 2/9] vhost: allow per device message handler Jason Wang
                   ` (8 subsequent siblings)
  9 siblings, 2 replies; 38+ messages in thread
From: Jason Wang @ 2020-03-26 14:01 UTC (permalink / raw)
  To: mst, linux-kernel, kvm, virtualization, netdev
  Cc: jgg, maxime.coquelin, cunming.liang, zhihong.wang, rob.miller,
	xiao.w.wang, lingshan.zhu, eperezma, lulu, parav, kevin.tian,
	stefanha, rdunlap, hch, aadam, jiri, shahafs, hanand, mhabets,
	gdawar, saugatm, vmireyno, zhangweining, Jason Wang

Currently, CONFIG_VHOST depends on CONFIG_VIRTUALIZATION. But vhost is
not necessarily for VM since it's a generic userspace and kernel
communication protocol. Such dependency may prevent archs without
virtualization support from using vhost.

To solve this, a dedicated vhost menu is created under drivers so
CONIFG_VHOST can be decoupled out of CONFIG_VIRTUALIZATION.

While at it, also squash Kconfig.vringh into vhost Kconfig file. This
avoids the trick of conditional inclusion from VOP or CAIF. Then it
will be easier to introduce new vringh users and common dependency for
both vringh and vhost.

Signed-off-by: Jason Wang <jasowang@redhat.com>
---
 arch/arm/kvm/Kconfig         |  2 --
 arch/arm64/kvm/Kconfig       |  2 --
 arch/mips/kvm/Kconfig        |  2 --
 arch/powerpc/kvm/Kconfig     |  2 --
 arch/s390/kvm/Kconfig        |  4 ----
 arch/x86/kvm/Kconfig         |  4 ----
 drivers/Kconfig              |  2 ++
 drivers/misc/mic/Kconfig     |  4 ----
 drivers/net/caif/Kconfig     |  4 ----
 drivers/vhost/Kconfig        | 23 ++++++++++++++---------
 drivers/vhost/Kconfig.vringh |  6 ------
 11 files changed, 16 insertions(+), 39 deletions(-)
 delete mode 100644 drivers/vhost/Kconfig.vringh

diff --git a/arch/arm/kvm/Kconfig b/arch/arm/kvm/Kconfig
index f591026347a5..be97393761bf 100644
--- a/arch/arm/kvm/Kconfig
+++ b/arch/arm/kvm/Kconfig
@@ -54,6 +54,4 @@ config KVM_ARM_HOST
 	---help---
 	  Provides host support for ARM processors.
 
-source "drivers/vhost/Kconfig"
-
 endif # VIRTUALIZATION
diff --git a/arch/arm64/kvm/Kconfig b/arch/arm64/kvm/Kconfig
index a475c68cbfec..449386d76441 100644
--- a/arch/arm64/kvm/Kconfig
+++ b/arch/arm64/kvm/Kconfig
@@ -64,6 +64,4 @@ config KVM_ARM_PMU
 config KVM_INDIRECT_VECTORS
        def_bool KVM && (HARDEN_BRANCH_PREDICTOR || HARDEN_EL2_VECTORS)
 
-source "drivers/vhost/Kconfig"
-
 endif # VIRTUALIZATION
diff --git a/arch/mips/kvm/Kconfig b/arch/mips/kvm/Kconfig
index eac25aef21e0..b91d145aa2d5 100644
--- a/arch/mips/kvm/Kconfig
+++ b/arch/mips/kvm/Kconfig
@@ -72,6 +72,4 @@ config KVM_MIPS_DEBUG_COP0_COUNTERS
 
 	  If unsure, say N.
 
-source "drivers/vhost/Kconfig"
-
 endif # VIRTUALIZATION
diff --git a/arch/powerpc/kvm/Kconfig b/arch/powerpc/kvm/Kconfig
index 711fca9bc6f0..12885eda324e 100644
--- a/arch/powerpc/kvm/Kconfig
+++ b/arch/powerpc/kvm/Kconfig
@@ -204,6 +204,4 @@ config KVM_XIVE
 	default y
 	depends on KVM_XICS && PPC_XIVE_NATIVE && KVM_BOOK3S_HV_POSSIBLE
 
-source "drivers/vhost/Kconfig"
-
 endif # VIRTUALIZATION
diff --git a/arch/s390/kvm/Kconfig b/arch/s390/kvm/Kconfig
index d3db3d7ed077..def3b60f1fe8 100644
--- a/arch/s390/kvm/Kconfig
+++ b/arch/s390/kvm/Kconfig
@@ -55,8 +55,4 @@ config KVM_S390_UCONTROL
 
 	  If unsure, say N.
 
-# OK, it's a little counter-intuitive to do this, but it puts it neatly under
-# the virtualization menu.
-source "drivers/vhost/Kconfig"
-
 endif # VIRTUALIZATION
diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig
index 991019d5eee1..0dfe70e17af9 100644
--- a/arch/x86/kvm/Kconfig
+++ b/arch/x86/kvm/Kconfig
@@ -94,8 +94,4 @@ config KVM_MMU_AUDIT
 	 This option adds a R/W kVM module parameter 'mmu_audit', which allows
 	 auditing of KVM MMU events at runtime.
 
-# OK, it's a little counter-intuitive to do this, but it puts it neatly under
-# the virtualization menu.
-source "drivers/vhost/Kconfig"
-
 endif # VIRTUALIZATION
diff --git a/drivers/Kconfig b/drivers/Kconfig
index 8befa53f43be..7a6d8b2b68b4 100644
--- a/drivers/Kconfig
+++ b/drivers/Kconfig
@@ -138,6 +138,8 @@ source "drivers/virt/Kconfig"
 
 source "drivers/virtio/Kconfig"
 
+source "drivers/vhost/Kconfig"
+
 source "drivers/hv/Kconfig"
 
 source "drivers/xen/Kconfig"
diff --git a/drivers/misc/mic/Kconfig b/drivers/misc/mic/Kconfig
index b6841ba6d922..8f201d019f5a 100644
--- a/drivers/misc/mic/Kconfig
+++ b/drivers/misc/mic/Kconfig
@@ -133,8 +133,4 @@ config VOP
 	  OS and tools for MIC to use with this driver are available from
 	  <http://software.intel.com/en-us/mic-developer>.
 
-if VOP
-source "drivers/vhost/Kconfig.vringh"
-endif
-
 endmenu
diff --git a/drivers/net/caif/Kconfig b/drivers/net/caif/Kconfig
index e74e2bb61236..9db0570c5beb 100644
--- a/drivers/net/caif/Kconfig
+++ b/drivers/net/caif/Kconfig
@@ -58,8 +58,4 @@ config CAIF_VIRTIO
 	---help---
 	  The CAIF driver for CAIF over Virtio.
 
-if CAIF_VIRTIO
-source "drivers/vhost/Kconfig.vringh"
-endif
-
 endif # CAIF_DRIVERS
diff --git a/drivers/vhost/Kconfig b/drivers/vhost/Kconfig
index 3d03ccbd1adc..4aef10a54cd1 100644
--- a/drivers/vhost/Kconfig
+++ b/drivers/vhost/Kconfig
@@ -1,8 +1,20 @@
 # SPDX-License-Identifier: GPL-2.0-only
+config VHOST_RING
+	tristate
+	help
+	  This option is selected by any driver which needs to access
+	  the host side of a virtio ring.
+
+menuconfig VHOST
+	tristate "Host kernel accelerator for virtio (VHOST)"
+	help
+	  This option is selected by any driver which needs to access
+	  the core of vhost.
+if VHOST
+
 config VHOST_NET
 	tristate "Host kernel accelerator for virtio net"
 	depends on NET && EVENTFD && (TUN || !TUN) && (TAP || !TAP)
-	select VHOST
 	---help---
 	  This kernel module can be loaded in host kernel to accelerate
 	  guest networking with virtio_net. Not to be confused with virtio_net
@@ -14,7 +26,6 @@ config VHOST_NET
 config VHOST_SCSI
 	tristate "VHOST_SCSI TCM fabric driver"
 	depends on TARGET_CORE && EVENTFD
-	select VHOST
 	default n
 	---help---
 	Say M here to enable the vhost_scsi TCM fabric module
@@ -24,7 +35,6 @@ config VHOST_VSOCK
 	tristate "vhost virtio-vsock driver"
 	depends on VSOCKETS && EVENTFD
 	select VIRTIO_VSOCKETS_COMMON
-	select VHOST
 	default n
 	---help---
 	This kernel module can be loaded in the host kernel to provide AF_VSOCK
@@ -34,12 +44,6 @@ config VHOST_VSOCK
 	To compile this driver as a module, choose M here: the module will be called
 	vhost_vsock.
 
-config VHOST
-	tristate
-	---help---
-	  This option is selected by any driver which needs to access
-	  the core of vhost.
-
 config VHOST_CROSS_ENDIAN_LEGACY
 	bool "Cross-endian support for vhost"
 	default n
@@ -54,3 +58,4 @@ config VHOST_CROSS_ENDIAN_LEGACY
 	  adds some overhead, it is disabled by default.
 
 	  If unsure, say "N".
+endif
diff --git a/drivers/vhost/Kconfig.vringh b/drivers/vhost/Kconfig.vringh
deleted file mode 100644
index c1fe36a9b8d4..000000000000
--- a/drivers/vhost/Kconfig.vringh
+++ /dev/null
@@ -1,6 +0,0 @@
-# SPDX-License-Identifier: GPL-2.0-only
-config VHOST_RING
-	tristate
-	---help---
-	  This option is selected by any driver which needs to access
-	  the host side of a virtio ring.
-- 
2.20.1


^ permalink raw reply	[flat|nested] 38+ messages in thread

* [PATCH V9 2/9] vhost: allow per device message handler
  2020-03-26 14:01 [PATCH V9 0/9] vDPA support Jason Wang
  2020-03-26 14:01 ` [PATCH V9 1/9] vhost: refine vhost and vringh kconfig Jason Wang
@ 2020-03-26 14:01 ` Jason Wang
  2020-03-26 14:01 ` [PATCH V9 3/9] vhost: factor out IOTLB Jason Wang
                   ` (7 subsequent siblings)
  9 siblings, 0 replies; 38+ messages in thread
From: Jason Wang @ 2020-03-26 14:01 UTC (permalink / raw)
  To: mst, linux-kernel, kvm, virtualization, netdev
  Cc: jgg, maxime.coquelin, cunming.liang, zhihong.wang, rob.miller,
	xiao.w.wang, lingshan.zhu, eperezma, lulu, parav, kevin.tian,
	stefanha, rdunlap, hch, aadam, jiri, shahafs, hanand, mhabets,
	gdawar, saugatm, vmireyno, zhangweining, Jason Wang

This patch allow device to register its own message handler during
vhost_dev_init(). vDPA device will use it to implement its own DMA
mapping logic.

Signed-off-by: Jason Wang <jasowang@redhat.com>
---
 drivers/vhost/net.c   |  3 ++-
 drivers/vhost/scsi.c  |  2 +-
 drivers/vhost/vhost.c | 12 ++++++++++--
 drivers/vhost/vhost.h |  6 +++++-
 drivers/vhost/vsock.c |  2 +-
 5 files changed, 19 insertions(+), 6 deletions(-)

diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c
index e158159671fa..c8ab8d83b530 100644
--- a/drivers/vhost/net.c
+++ b/drivers/vhost/net.c
@@ -1324,7 +1324,8 @@ static int vhost_net_open(struct inode *inode, struct file *f)
 	}
 	vhost_dev_init(dev, vqs, VHOST_NET_VQ_MAX,
 		       UIO_MAXIOV + VHOST_NET_BATCH,
-		       VHOST_NET_PKT_WEIGHT, VHOST_NET_WEIGHT);
+		       VHOST_NET_PKT_WEIGHT, VHOST_NET_WEIGHT,
+		       NULL);
 
 	vhost_poll_init(n->poll + VHOST_NET_VQ_TX, handle_tx_net, EPOLLOUT, dev);
 	vhost_poll_init(n->poll + VHOST_NET_VQ_RX, handle_rx_net, EPOLLIN, dev);
diff --git a/drivers/vhost/scsi.c b/drivers/vhost/scsi.c
index 0b949a14bce3..7653667a8cdc 100644
--- a/drivers/vhost/scsi.c
+++ b/drivers/vhost/scsi.c
@@ -1628,7 +1628,7 @@ static int vhost_scsi_open(struct inode *inode, struct file *f)
 		vs->vqs[i].vq.handle_kick = vhost_scsi_handle_kick;
 	}
 	vhost_dev_init(&vs->dev, vqs, VHOST_SCSI_MAX_VQ, UIO_MAXIOV,
-		       VHOST_SCSI_WEIGHT, 0);
+		       VHOST_SCSI_WEIGHT, 0, NULL);
 
 	vhost_scsi_init_inflight(vs, NULL);
 
diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
index f44340b41494..8e9e2341e40a 100644
--- a/drivers/vhost/vhost.c
+++ b/drivers/vhost/vhost.c
@@ -457,7 +457,9 @@ static size_t vhost_get_desc_size(struct vhost_virtqueue *vq,
 
 void vhost_dev_init(struct vhost_dev *dev,
 		    struct vhost_virtqueue **vqs, int nvqs,
-		    int iov_limit, int weight, int byte_weight)
+		    int iov_limit, int weight, int byte_weight,
+		    int (*msg_handler)(struct vhost_dev *dev,
+				       struct vhost_iotlb_msg *msg))
 {
 	struct vhost_virtqueue *vq;
 	int i;
@@ -473,6 +475,7 @@ void vhost_dev_init(struct vhost_dev *dev,
 	dev->iov_limit = iov_limit;
 	dev->weight = weight;
 	dev->byte_weight = byte_weight;
+	dev->msg_handler = msg_handler;
 	init_llist_head(&dev->work_list);
 	init_waitqueue_head(&dev->wait);
 	INIT_LIST_HEAD(&dev->read_list);
@@ -1178,7 +1181,12 @@ ssize_t vhost_chr_write_iter(struct vhost_dev *dev,
 		ret = -EINVAL;
 		goto done;
 	}
-	if (vhost_process_iotlb_msg(dev, &msg)) {
+
+	if (dev->msg_handler)
+		ret = dev->msg_handler(dev, &msg);
+	else
+		ret = vhost_process_iotlb_msg(dev, &msg);
+	if (ret) {
 		ret = -EFAULT;
 		goto done;
 	}
diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h
index a123fd70847e..f9d1a03dd153 100644
--- a/drivers/vhost/vhost.h
+++ b/drivers/vhost/vhost.h
@@ -174,11 +174,15 @@ struct vhost_dev {
 	int weight;
 	int byte_weight;
 	u64 kcov_handle;
+	int (*msg_handler)(struct vhost_dev *dev,
+			   struct vhost_iotlb_msg *msg);
 };
 
 bool vhost_exceeds_weight(struct vhost_virtqueue *vq, int pkts, int total_len);
 void vhost_dev_init(struct vhost_dev *, struct vhost_virtqueue **vqs,
-		    int nvqs, int iov_limit, int weight, int byte_weight);
+		    int nvqs, int iov_limit, int weight, int byte_weight,
+		    int (*msg_handler)(struct vhost_dev *dev,
+				       struct vhost_iotlb_msg *msg));
 long vhost_dev_set_owner(struct vhost_dev *dev);
 bool vhost_dev_has_owner(struct vhost_dev *dev);
 long vhost_dev_check_owner(struct vhost_dev *);
diff --git a/drivers/vhost/vsock.c b/drivers/vhost/vsock.c
index c2d7d57e98cf..97669484a3f6 100644
--- a/drivers/vhost/vsock.c
+++ b/drivers/vhost/vsock.c
@@ -621,7 +621,7 @@ static int vhost_vsock_dev_open(struct inode *inode, struct file *file)
 
 	vhost_dev_init(&vsock->dev, vqs, ARRAY_SIZE(vsock->vqs),
 		       UIO_MAXIOV, VHOST_VSOCK_PKT_WEIGHT,
-		       VHOST_VSOCK_WEIGHT);
+		       VHOST_VSOCK_WEIGHT, NULL);
 
 	file->private_data = vsock;
 	spin_lock_init(&vsock->send_pkt_list_lock);
-- 
2.20.1


^ permalink raw reply	[flat|nested] 38+ messages in thread

* [PATCH V9 3/9] vhost: factor out IOTLB
  2020-03-26 14:01 [PATCH V9 0/9] vDPA support Jason Wang
  2020-03-26 14:01 ` [PATCH V9 1/9] vhost: refine vhost and vringh kconfig Jason Wang
  2020-03-26 14:01 ` [PATCH V9 2/9] vhost: allow per device message handler Jason Wang
@ 2020-03-26 14:01 ` Jason Wang
  2020-03-26 14:01 ` [PATCH V9 4/9] vringh: IOTLB support Jason Wang
                   ` (6 subsequent siblings)
  9 siblings, 0 replies; 38+ messages in thread
From: Jason Wang @ 2020-03-26 14:01 UTC (permalink / raw)
  To: mst, linux-kernel, kvm, virtualization, netdev
  Cc: jgg, maxime.coquelin, cunming.liang, zhihong.wang, rob.miller,
	xiao.w.wang, lingshan.zhu, eperezma, lulu, parav, kevin.tian,
	stefanha, rdunlap, hch, aadam, jiri, shahafs, hanand, mhabets,
	gdawar, saugatm, vmireyno, zhangweining, Jason Wang

This patch factors out IOTLB into a dedicated module in order to be
reused by other modules like vringh. User may choose to enable the
automatic retiring by specifying VHOST_IOTLB_FLAG_RETIRE flag to fit
for the case of vhost device IOTLB implementation.

Signed-off-by: Jason Wang <jasowang@redhat.com>
---
 MAINTAINERS                 |   1 +
 drivers/vhost/Kconfig       |   9 ++
 drivers/vhost/Makefile      |   3 +
 drivers/vhost/iotlb.c       | 177 +++++++++++++++++++++++++++++
 drivers/vhost/net.c         |   2 +-
 drivers/vhost/vhost.c       | 221 +++++++++++-------------------------
 drivers/vhost/vhost.h       |  39 ++-----
 include/linux/vhost_iotlb.h |  47 ++++++++
 8 files changed, 318 insertions(+), 181 deletions(-)
 create mode 100644 drivers/vhost/iotlb.c
 create mode 100644 include/linux/vhost_iotlb.h

diff --git a/MAINTAINERS b/MAINTAINERS
index c74e4ea714a5..0fb645b5a7df 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -17768,6 +17768,7 @@ T:	git git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost.git
 S:	Maintained
 F:	drivers/vhost/
 F:	include/uapi/linux/vhost.h
+F:	include/linux/vhost_iotlb.h
 
 VIRTIO INPUT DRIVER
 M:	Gerd Hoffmann <kraxel@redhat.com>
diff --git a/drivers/vhost/Kconfig b/drivers/vhost/Kconfig
index 4aef10a54cd1..2f6c2105b953 100644
--- a/drivers/vhost/Kconfig
+++ b/drivers/vhost/Kconfig
@@ -1,4 +1,9 @@
 # SPDX-License-Identifier: GPL-2.0-only
+config VHOST_IOTLB
+	tristate
+	help
+	  Generic IOTLB implementation for vhost and vringh.
+
 config VHOST_RING
 	tristate
 	help
@@ -7,9 +12,11 @@ config VHOST_RING
 
 menuconfig VHOST
 	tristate "Host kernel accelerator for virtio (VHOST)"
+	select VHOST_IOTLB
 	help
 	  This option is selected by any driver which needs to access
 	  the core of vhost.
+
 if VHOST
 
 config VHOST_NET
@@ -58,4 +65,6 @@ config VHOST_CROSS_ENDIAN_LEGACY
 	  adds some overhead, it is disabled by default.
 
 	  If unsure, say "N".
+
 endif
+
diff --git a/drivers/vhost/Makefile b/drivers/vhost/Makefile
index 6c6df24f770c..fb831002bcf0 100644
--- a/drivers/vhost/Makefile
+++ b/drivers/vhost/Makefile
@@ -11,3 +11,6 @@ vhost_vsock-y := vsock.o
 obj-$(CONFIG_VHOST_RING) += vringh.o
 
 obj-$(CONFIG_VHOST)	+= vhost.o
+
+obj-$(CONFIG_VHOST_IOTLB) += vhost_iotlb.o
+vhost_iotlb-y := iotlb.o
diff --git a/drivers/vhost/iotlb.c b/drivers/vhost/iotlb.c
new file mode 100644
index 000000000000..1f0ca6e44410
--- /dev/null
+++ b/drivers/vhost/iotlb.c
@@ -0,0 +1,177 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright (C) 2020 Red Hat, Inc.
+ * Author: Jason Wang <jasowang@redhat.com>
+ *
+ * IOTLB implementation for vhost.
+ */
+#include <linux/slab.h>
+#include <linux/vhost_iotlb.h>
+#include <linux/module.h>
+
+#define MOD_VERSION  "0.1"
+#define MOD_DESC     "VHOST IOTLB"
+#define MOD_AUTHOR   "Jason Wang <jasowang@redhat.com>"
+#define MOD_LICENSE  "GPL v2"
+
+#define START(map) ((map)->start)
+#define LAST(map) ((map)->last)
+
+INTERVAL_TREE_DEFINE(struct vhost_iotlb_map,
+		     rb, __u64, __subtree_last,
+		     START, LAST, static inline, vhost_iotlb_itree);
+
+/**
+ * vhost_iotlb_map_free - remove a map node and free it
+ * @iotlb: the IOTLB
+ * @map: the map that want to be remove and freed
+ */
+void vhost_iotlb_map_free(struct vhost_iotlb *iotlb,
+			  struct vhost_iotlb_map *map)
+{
+	vhost_iotlb_itree_remove(map, &iotlb->root);
+	list_del(&map->link);
+	kfree(map);
+	iotlb->nmaps--;
+}
+EXPORT_SYMBOL_GPL(vhost_iotlb_map_free);
+
+/**
+ * vhost_iotlb_add_range - add a new range to vhost IOTLB
+ * @iotlb: the IOTLB
+ * @start: start of the IOVA range
+ * @last: last of IOVA range
+ * @addr: the address that is mapped to @start
+ * @perm: access permission of this range
+ *
+ * Returns an error last is smaller than start or memory allocation
+ * fails
+ */
+int vhost_iotlb_add_range(struct vhost_iotlb *iotlb,
+			  u64 start, u64 last,
+			  u64 addr, unsigned int perm)
+{
+	struct vhost_iotlb_map *map;
+
+	if (last < start)
+		return -EFAULT;
+
+	if (iotlb->limit &&
+	    iotlb->nmaps == iotlb->limit &&
+	    iotlb->flags & VHOST_IOTLB_FLAG_RETIRE) {
+		map = list_first_entry(&iotlb->list, typeof(*map), link);
+		vhost_iotlb_map_free(iotlb, map);
+	}
+
+	map = kmalloc(sizeof(*map), GFP_ATOMIC);
+	if (!map)
+		return -ENOMEM;
+
+	map->start = start;
+	map->size = last - start + 1;
+	map->last = last;
+	map->addr = addr;
+	map->perm = perm;
+
+	iotlb->nmaps++;
+	vhost_iotlb_itree_insert(map, &iotlb->root);
+
+	INIT_LIST_HEAD(&map->link);
+	list_add_tail(&map->link, &iotlb->list);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(vhost_iotlb_add_range);
+
+/**
+ * vring_iotlb_del_range - delete overlapped ranges from vhost IOTLB
+ * @iotlb: the IOTLB
+ * @start: start of the IOVA range
+ * @last: last of IOVA range
+ */
+void vhost_iotlb_del_range(struct vhost_iotlb *iotlb, u64 start, u64 last)
+{
+	struct vhost_iotlb_map *map;
+
+	while ((map = vhost_iotlb_itree_iter_first(&iotlb->root,
+						   start, last)))
+		vhost_iotlb_map_free(iotlb, map);
+}
+EXPORT_SYMBOL_GPL(vhost_iotlb_del_range);
+
+/**
+ * vhost_iotlb_alloc - add a new vhost IOTLB
+ * @limit: maximum number of IOTLB entries
+ * @flags: VHOST_IOTLB_FLAG_XXX
+ *
+ * Returns an error is memory allocation fails
+ */
+struct vhost_iotlb *vhost_iotlb_alloc(unsigned int limit, unsigned int flags)
+{
+	struct vhost_iotlb *iotlb = kzalloc(sizeof(*iotlb), GFP_KERNEL);
+
+	if (!iotlb)
+		return NULL;
+
+	iotlb->root = RB_ROOT_CACHED;
+	iotlb->limit = limit;
+	iotlb->nmaps = 0;
+	iotlb->flags = flags;
+	INIT_LIST_HEAD(&iotlb->list);
+
+	return iotlb;
+}
+EXPORT_SYMBOL_GPL(vhost_iotlb_alloc);
+
+/**
+ * vhost_iotlb_reset - reset vhost IOTLB (free all IOTLB entries)
+ * @iotlb: the IOTLB to be reset
+ */
+void vhost_iotlb_reset(struct vhost_iotlb *iotlb)
+{
+	vhost_iotlb_del_range(iotlb, 0ULL, 0ULL - 1);
+}
+EXPORT_SYMBOL_GPL(vhost_iotlb_reset);
+
+/**
+ * vhost_iotlb_free - reset and free vhost IOTLB
+ * @iotlb: the IOTLB to be freed
+ */
+void vhost_iotlb_free(struct vhost_iotlb *iotlb)
+{
+	if (iotlb) {
+		vhost_iotlb_reset(iotlb);
+		kfree(iotlb);
+	}
+}
+EXPORT_SYMBOL_GPL(vhost_iotlb_free);
+
+/**
+ * vhost_iotlb_itree_first - return the first overlapped range
+ * @iotlb: the IOTLB
+ * @start: start of IOVA range
+ * @end: end of IOVA range
+ */
+struct vhost_iotlb_map *
+vhost_iotlb_itree_first(struct vhost_iotlb *iotlb, u64 start, u64 last)
+{
+	return vhost_iotlb_itree_iter_first(&iotlb->root, start, last);
+}
+EXPORT_SYMBOL_GPL(vhost_iotlb_itree_first);
+
+/**
+ * vhost_iotlb_itree_first - return the next overlapped range
+ * @iotlb: the IOTLB
+ * @start: start of IOVA range
+ * @end: end of IOVA range
+ */
+struct vhost_iotlb_map *
+vhost_iotlb_itree_next(struct vhost_iotlb_map *map, u64 start, u64 last)
+{
+	return vhost_iotlb_itree_iter_next(map, start, last);
+}
+EXPORT_SYMBOL_GPL(vhost_iotlb_itree_next);
+
+MODULE_VERSION(MOD_VERSION);
+MODULE_DESCRIPTION(MOD_DESC);
+MODULE_AUTHOR(MOD_AUTHOR);
+MODULE_LICENSE(MOD_LICENSE);
diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c
index c8ab8d83b530..c7298b192ab4 100644
--- a/drivers/vhost/net.c
+++ b/drivers/vhost/net.c
@@ -1595,7 +1595,7 @@ static long vhost_net_reset_owner(struct vhost_net *n)
 	struct socket *tx_sock = NULL;
 	struct socket *rx_sock = NULL;
 	long err;
-	struct vhost_umem *umem;
+	struct vhost_iotlb *umem;
 
 	mutex_lock(&n->dev.mutex);
 	err = vhost_dev_check_owner(&n->dev);
diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
index 8e9e2341e40a..d450e16c5c25 100644
--- a/drivers/vhost/vhost.c
+++ b/drivers/vhost/vhost.c
@@ -50,10 +50,6 @@ enum {
 #define vhost_used_event(vq) ((__virtio16 __user *)&vq->avail->ring[vq->num])
 #define vhost_avail_event(vq) ((__virtio16 __user *)&vq->used->ring[vq->num])
 
-INTERVAL_TREE_DEFINE(struct vhost_umem_node,
-		     rb, __u64, __subtree_last,
-		     START, LAST, static inline, vhost_umem_interval_tree);
-
 #ifdef CONFIG_VHOST_CROSS_ENDIAN_LEGACY
 static void vhost_disable_cross_endian(struct vhost_virtqueue *vq)
 {
@@ -584,21 +580,25 @@ long vhost_dev_set_owner(struct vhost_dev *dev)
 }
 EXPORT_SYMBOL_GPL(vhost_dev_set_owner);
 
-struct vhost_umem *vhost_dev_reset_owner_prepare(void)
+static struct vhost_iotlb *iotlb_alloc(void)
+{
+	return vhost_iotlb_alloc(max_iotlb_entries,
+				 VHOST_IOTLB_FLAG_RETIRE);
+}
+
+struct vhost_iotlb *vhost_dev_reset_owner_prepare(void)
 {
-	return kvzalloc(sizeof(struct vhost_umem), GFP_KERNEL);
+	return iotlb_alloc();
 }
 EXPORT_SYMBOL_GPL(vhost_dev_reset_owner_prepare);
 
 /* Caller should have device mutex */
-void vhost_dev_reset_owner(struct vhost_dev *dev, struct vhost_umem *umem)
+void vhost_dev_reset_owner(struct vhost_dev *dev, struct vhost_iotlb *umem)
 {
 	int i;
 
 	vhost_dev_cleanup(dev);
 
-	/* Restore memory to default empty mapping. */
-	INIT_LIST_HEAD(&umem->umem_list);
 	dev->umem = umem;
 	/* We don't need VQ locks below since vhost_dev_cleanup makes sure
 	 * VQs aren't running.
@@ -621,28 +621,6 @@ void vhost_dev_stop(struct vhost_dev *dev)
 }
 EXPORT_SYMBOL_GPL(vhost_dev_stop);
 
-static void vhost_umem_free(struct vhost_umem *umem,
-			    struct vhost_umem_node *node)
-{
-	vhost_umem_interval_tree_remove(node, &umem->umem_tree);
-	list_del(&node->link);
-	kfree(node);
-	umem->numem--;
-}
-
-static void vhost_umem_clean(struct vhost_umem *umem)
-{
-	struct vhost_umem_node *node, *tmp;
-
-	if (!umem)
-		return;
-
-	list_for_each_entry_safe(node, tmp, &umem->umem_list, link)
-		vhost_umem_free(umem, node);
-
-	kvfree(umem);
-}
-
 static void vhost_clear_msg(struct vhost_dev *dev)
 {
 	struct vhost_msg_node *node, *n;
@@ -680,9 +658,9 @@ void vhost_dev_cleanup(struct vhost_dev *dev)
 		eventfd_ctx_put(dev->log_ctx);
 	dev->log_ctx = NULL;
 	/* No one will access memory at this point */
-	vhost_umem_clean(dev->umem);
+	vhost_iotlb_free(dev->umem);
 	dev->umem = NULL;
-	vhost_umem_clean(dev->iotlb);
+	vhost_iotlb_free(dev->iotlb);
 	dev->iotlb = NULL;
 	vhost_clear_msg(dev);
 	wake_up_interruptible_poll(&dev->wait, EPOLLIN | EPOLLRDNORM);
@@ -718,27 +696,26 @@ static bool vhost_overflow(u64 uaddr, u64 size)
 }
 
 /* Caller should have vq mutex and device mutex. */
-static bool vq_memory_access_ok(void __user *log_base, struct vhost_umem *umem,
+static bool vq_memory_access_ok(void __user *log_base, struct vhost_iotlb *umem,
 				int log_all)
 {
-	struct vhost_umem_node *node;
+	struct vhost_iotlb_map *map;
 
 	if (!umem)
 		return false;
 
-	list_for_each_entry(node, &umem->umem_list, link) {
-		unsigned long a = node->userspace_addr;
+	list_for_each_entry(map, &umem->list, link) {
+		unsigned long a = map->addr;
 
-		if (vhost_overflow(node->userspace_addr, node->size))
+		if (vhost_overflow(map->addr, map->size))
 			return false;
 
 
-		if (!access_ok((void __user *)a,
-				    node->size))
+		if (!access_ok((void __user *)a, map->size))
 			return false;
 		else if (log_all && !log_access_ok(log_base,
-						   node->start,
-						   node->size))
+						   map->start,
+						   map->size))
 			return false;
 	}
 	return true;
@@ -748,17 +725,17 @@ static inline void __user *vhost_vq_meta_fetch(struct vhost_virtqueue *vq,
 					       u64 addr, unsigned int size,
 					       int type)
 {
-	const struct vhost_umem_node *node = vq->meta_iotlb[type];
+	const struct vhost_iotlb_map *map = vq->meta_iotlb[type];
 
-	if (!node)
+	if (!map)
 		return NULL;
 
-	return (void *)(uintptr_t)(node->userspace_addr + addr - node->start);
+	return (void *)(uintptr_t)(map->addr + addr - map->start);
 }
 
 /* Can we switch to this memory table? */
 /* Caller should have device mutex but not vq mutex */
-static bool memory_access_ok(struct vhost_dev *d, struct vhost_umem *umem,
+static bool memory_access_ok(struct vhost_dev *d, struct vhost_iotlb *umem,
 			     int log_all)
 {
 	int i;
@@ -1023,47 +1000,6 @@ static inline int vhost_get_desc(struct vhost_virtqueue *vq,
 	return vhost_copy_from_user(vq, desc, vq->desc + idx, sizeof(*desc));
 }
 
-static int vhost_new_umem_range(struct vhost_umem *umem,
-				u64 start, u64 size, u64 end,
-				u64 userspace_addr, int perm)
-{
-	struct vhost_umem_node *tmp, *node;
-
-	if (!size)
-		return -EFAULT;
-
-	node = kmalloc(sizeof(*node), GFP_ATOMIC);
-	if (!node)
-		return -ENOMEM;
-
-	if (umem->numem == max_iotlb_entries) {
-		tmp = list_first_entry(&umem->umem_list, typeof(*tmp), link);
-		vhost_umem_free(umem, tmp);
-	}
-
-	node->start = start;
-	node->size = size;
-	node->last = end;
-	node->userspace_addr = userspace_addr;
-	node->perm = perm;
-	INIT_LIST_HEAD(&node->link);
-	list_add_tail(&node->link, &umem->umem_list);
-	vhost_umem_interval_tree_insert(node, &umem->umem_tree);
-	umem->numem++;
-
-	return 0;
-}
-
-static void vhost_del_umem_range(struct vhost_umem *umem,
-				 u64 start, u64 end)
-{
-	struct vhost_umem_node *node;
-
-	while ((node = vhost_umem_interval_tree_iter_first(&umem->umem_tree,
-							   start, end)))
-		vhost_umem_free(umem, node);
-}
-
 static void vhost_iotlb_notify_vq(struct vhost_dev *d,
 				  struct vhost_iotlb_msg *msg)
 {
@@ -1120,9 +1056,9 @@ static int vhost_process_iotlb_msg(struct vhost_dev *dev,
 			break;
 		}
 		vhost_vq_meta_reset(dev);
-		if (vhost_new_umem_range(dev->iotlb, msg->iova, msg->size,
-					 msg->iova + msg->size - 1,
-					 msg->uaddr, msg->perm)) {
+		if (vhost_iotlb_add_range(dev->iotlb, msg->iova,
+					  msg->iova + msg->size - 1,
+					  msg->uaddr, msg->perm)) {
 			ret = -ENOMEM;
 			break;
 		}
@@ -1134,8 +1070,8 @@ static int vhost_process_iotlb_msg(struct vhost_dev *dev,
 			break;
 		}
 		vhost_vq_meta_reset(dev);
-		vhost_del_umem_range(dev->iotlb, msg->iova,
-				     msg->iova + msg->size - 1);
+		vhost_iotlb_del_range(dev->iotlb, msg->iova,
+				      msg->iova + msg->size - 1);
 		break;
 	default:
 		ret = -EINVAL;
@@ -1319,44 +1255,42 @@ static bool vq_access_ok(struct vhost_virtqueue *vq, unsigned int num,
 }
 
 static void vhost_vq_meta_update(struct vhost_virtqueue *vq,
-				 const struct vhost_umem_node *node,
+				 const struct vhost_iotlb_map *map,
 				 int type)
 {
 	int access = (type == VHOST_ADDR_USED) ?
 		     VHOST_ACCESS_WO : VHOST_ACCESS_RO;
 
-	if (likely(node->perm & access))
-		vq->meta_iotlb[type] = node;
+	if (likely(map->perm & access))
+		vq->meta_iotlb[type] = map;
 }
 
 static bool iotlb_access_ok(struct vhost_virtqueue *vq,
 			    int access, u64 addr, u64 len, int type)
 {
-	const struct vhost_umem_node *node;
-	struct vhost_umem *umem = vq->iotlb;
+	const struct vhost_iotlb_map *map;
+	struct vhost_iotlb *umem = vq->iotlb;
 	u64 s = 0, size, orig_addr = addr, last = addr + len - 1;
 
 	if (vhost_vq_meta_fetch(vq, addr, len, type))
 		return true;
 
 	while (len > s) {
-		node = vhost_umem_interval_tree_iter_first(&umem->umem_tree,
-							   addr,
-							   last);
-		if (node == NULL || node->start > addr) {
+		map = vhost_iotlb_itree_first(umem, addr, last);
+		if (map == NULL || map->start > addr) {
 			vhost_iotlb_miss(vq, addr, access);
 			return false;
-		} else if (!(node->perm & access)) {
+		} else if (!(map->perm & access)) {
 			/* Report the possible access violation by
 			 * request another translation from userspace.
 			 */
 			return false;
 		}
 
-		size = node->size - addr + node->start;
+		size = map->size - addr + map->start;
 
 		if (orig_addr == addr && size >= len)
-			vhost_vq_meta_update(vq, node, type);
+			vhost_vq_meta_update(vq, map, type);
 
 		s += size;
 		addr += size;
@@ -1372,12 +1306,12 @@ int vq_meta_prefetch(struct vhost_virtqueue *vq)
 	if (!vq->iotlb)
 		return 1;
 
-	return iotlb_access_ok(vq, VHOST_ACCESS_RO, (u64)(uintptr_t)vq->desc,
+	return iotlb_access_ok(vq, VHOST_MAP_RO, (u64)(uintptr_t)vq->desc,
 			       vhost_get_desc_size(vq, num), VHOST_ADDR_DESC) &&
-	       iotlb_access_ok(vq, VHOST_ACCESS_RO, (u64)(uintptr_t)vq->avail,
+	       iotlb_access_ok(vq, VHOST_MAP_RO, (u64)(uintptr_t)vq->avail,
 			       vhost_get_avail_size(vq, num),
 			       VHOST_ADDR_AVAIL) &&
-	       iotlb_access_ok(vq, VHOST_ACCESS_WO, (u64)(uintptr_t)vq->used,
+	       iotlb_access_ok(vq, VHOST_MAP_WO, (u64)(uintptr_t)vq->used,
 			       vhost_get_used_size(vq, num), VHOST_ADDR_USED);
 }
 EXPORT_SYMBOL_GPL(vq_meta_prefetch);
@@ -1416,25 +1350,11 @@ bool vhost_vq_access_ok(struct vhost_virtqueue *vq)
 }
 EXPORT_SYMBOL_GPL(vhost_vq_access_ok);
 
-static struct vhost_umem *vhost_umem_alloc(void)
-{
-	struct vhost_umem *umem = kvzalloc(sizeof(*umem), GFP_KERNEL);
-
-	if (!umem)
-		return NULL;
-
-	umem->umem_tree = RB_ROOT_CACHED;
-	umem->numem = 0;
-	INIT_LIST_HEAD(&umem->umem_list);
-
-	return umem;
-}
-
 static long vhost_set_memory(struct vhost_dev *d, struct vhost_memory __user *m)
 {
 	struct vhost_memory mem, *newmem;
 	struct vhost_memory_region *region;
-	struct vhost_umem *newumem, *oldumem;
+	struct vhost_iotlb *newumem, *oldumem;
 	unsigned long size = offsetof(struct vhost_memory, regions);
 	int i;
 
@@ -1456,7 +1376,7 @@ static long vhost_set_memory(struct vhost_dev *d, struct vhost_memory __user *m)
 		return -EFAULT;
 	}
 
-	newumem = vhost_umem_alloc();
+	newumem = iotlb_alloc();
 	if (!newumem) {
 		kvfree(newmem);
 		return -ENOMEM;
@@ -1465,13 +1385,12 @@ static long vhost_set_memory(struct vhost_dev *d, struct vhost_memory __user *m)
 	for (region = newmem->regions;
 	     region < newmem->regions + mem.nregions;
 	     region++) {
-		if (vhost_new_umem_range(newumem,
-					 region->guest_phys_addr,
-					 region->memory_size,
-					 region->guest_phys_addr +
-					 region->memory_size - 1,
-					 region->userspace_addr,
-					 VHOST_ACCESS_RW))
+		if (vhost_iotlb_add_range(newumem,
+					  region->guest_phys_addr,
+					  region->guest_phys_addr +
+					  region->memory_size - 1,
+					  region->userspace_addr,
+					  VHOST_MAP_RW))
 			goto err;
 	}
 
@@ -1489,11 +1408,11 @@ static long vhost_set_memory(struct vhost_dev *d, struct vhost_memory __user *m)
 	}
 
 	kvfree(newmem);
-	vhost_umem_clean(oldumem);
+	vhost_iotlb_free(oldumem);
 	return 0;
 
 err:
-	vhost_umem_clean(newumem);
+	vhost_iotlb_free(newumem);
 	kvfree(newmem);
 	return -EFAULT;
 }
@@ -1734,10 +1653,10 @@ EXPORT_SYMBOL_GPL(vhost_vring_ioctl);
 
 int vhost_init_device_iotlb(struct vhost_dev *d, bool enabled)
 {
-	struct vhost_umem *niotlb, *oiotlb;
+	struct vhost_iotlb *niotlb, *oiotlb;
 	int i;
 
-	niotlb = vhost_umem_alloc();
+	niotlb = iotlb_alloc();
 	if (!niotlb)
 		return -ENOMEM;
 
@@ -1753,7 +1672,7 @@ int vhost_init_device_iotlb(struct vhost_dev *d, bool enabled)
 		mutex_unlock(&vq->mutex);
 	}
 
-	vhost_umem_clean(oiotlb);
+	vhost_iotlb_free(oiotlb);
 
 	return 0;
 }
@@ -1883,8 +1802,8 @@ static int log_write(void __user *log_base,
 
 static int log_write_hva(struct vhost_virtqueue *vq, u64 hva, u64 len)
 {
-	struct vhost_umem *umem = vq->umem;
-	struct vhost_umem_node *u;
+	struct vhost_iotlb *umem = vq->umem;
+	struct vhost_iotlb_map *u;
 	u64 start, end, l, min;
 	int r;
 	bool hit = false;
@@ -1894,16 +1813,15 @@ static int log_write_hva(struct vhost_virtqueue *vq, u64 hva, u64 len)
 		/* More than one GPAs can be mapped into a single HVA. So
 		 * iterate all possible umems here to be safe.
 		 */
-		list_for_each_entry(u, &umem->umem_list, link) {
-			if (u->userspace_addr > hva - 1 + len ||
-			    u->userspace_addr - 1 + u->size < hva)
+		list_for_each_entry(u, &umem->list, link) {
+			if (u->addr > hva - 1 + len ||
+			    u->addr - 1 + u->size < hva)
 				continue;
-			start = max(u->userspace_addr, hva);
-			end = min(u->userspace_addr - 1 + u->size,
-				  hva - 1 + len);
+			start = max(u->addr, hva);
+			end = min(u->addr - 1 + u->size, hva - 1 + len);
 			l = end - start + 1;
 			r = log_write(vq->log_base,
-				      u->start + start - u->userspace_addr,
+				      u->start + start - u->addr,
 				      l);
 			if (r < 0)
 				return r;
@@ -2054,9 +1972,9 @@ EXPORT_SYMBOL_GPL(vhost_vq_init_access);
 static int translate_desc(struct vhost_virtqueue *vq, u64 addr, u32 len,
 			  struct iovec iov[], int iov_size, int access)
 {
-	const struct vhost_umem_node *node;
+	const struct vhost_iotlb_map *map;
 	struct vhost_dev *dev = vq->dev;
-	struct vhost_umem *umem = dev->iotlb ? dev->iotlb : dev->umem;
+	struct vhost_iotlb *umem = dev->iotlb ? dev->iotlb : dev->umem;
 	struct iovec *_iov;
 	u64 s = 0;
 	int ret = 0;
@@ -2068,25 +1986,24 @@ static int translate_desc(struct vhost_virtqueue *vq, u64 addr, u32 len,
 			break;
 		}
 
-		node = vhost_umem_interval_tree_iter_first(&umem->umem_tree,
-							addr, addr + len - 1);
-		if (node == NULL || node->start > addr) {
+		map = vhost_iotlb_itree_first(umem, addr, addr + len - 1);
+		if (map == NULL || map->start > addr) {
 			if (umem != dev->iotlb) {
 				ret = -EFAULT;
 				break;
 			}
 			ret = -EAGAIN;
 			break;
-		} else if (!(node->perm & access)) {
+		} else if (!(map->perm & access)) {
 			ret = -EPERM;
 			break;
 		}
 
 		_iov = iov + ret;
-		size = node->size - addr + node->start;
+		size = map->size - addr + map->start;
 		_iov->iov_len = min((u64)len - s, size);
 		_iov->iov_base = (void __user *)(unsigned long)
-			(node->userspace_addr + addr - node->start);
+				 (map->addr + addr - map->start);
 		s += size;
 		addr += size;
 		++ret;
diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h
index f9d1a03dd153..181382185bbc 100644
--- a/drivers/vhost/vhost.h
+++ b/drivers/vhost/vhost.h
@@ -12,6 +12,7 @@
 #include <linux/virtio_config.h>
 #include <linux/virtio_ring.h>
 #include <linux/atomic.h>
+#include <linux/vhost_iotlb.h>
 
 struct vhost_work;
 typedef void (*vhost_work_fn_t)(struct vhost_work *work);
@@ -52,27 +53,6 @@ struct vhost_log {
 	u64 len;
 };
 
-#define START(node) ((node)->start)
-#define LAST(node) ((node)->last)
-
-struct vhost_umem_node {
-	struct rb_node rb;
-	struct list_head link;
-	__u64 start;
-	__u64 last;
-	__u64 size;
-	__u64 userspace_addr;
-	__u32 perm;
-	__u32 flags_padding;
-	__u64 __subtree_last;
-};
-
-struct vhost_umem {
-	struct rb_root_cached umem_tree;
-	struct list_head umem_list;
-	int numem;
-};
-
 enum vhost_uaddr_type {
 	VHOST_ADDR_DESC = 0,
 	VHOST_ADDR_AVAIL = 1,
@@ -90,7 +70,7 @@ struct vhost_virtqueue {
 	struct vring_desc __user *desc;
 	struct vring_avail __user *avail;
 	struct vring_used __user *used;
-	const struct vhost_umem_node *meta_iotlb[VHOST_NUM_ADDRS];
+	const struct vhost_iotlb_map *meta_iotlb[VHOST_NUM_ADDRS];
 	struct file *kick;
 	struct eventfd_ctx *call_ctx;
 	struct eventfd_ctx *error_ctx;
@@ -128,8 +108,8 @@ struct vhost_virtqueue {
 	struct iovec *indirect;
 	struct vring_used_elem *heads;
 	/* Protected by virtqueue mutex. */
-	struct vhost_umem *umem;
-	struct vhost_umem *iotlb;
+	struct vhost_iotlb *umem;
+	struct vhost_iotlb *iotlb;
 	void *private_data;
 	u64 acked_features;
 	u64 acked_backend_features;
@@ -164,8 +144,8 @@ struct vhost_dev {
 	struct eventfd_ctx *log_ctx;
 	struct llist_head work_list;
 	struct task_struct *worker;
-	struct vhost_umem *umem;
-	struct vhost_umem *iotlb;
+	struct vhost_iotlb *umem;
+	struct vhost_iotlb *iotlb;
 	spinlock_t iotlb_lock;
 	struct list_head read_list;
 	struct list_head pending_list;
@@ -186,8 +166,8 @@ void vhost_dev_init(struct vhost_dev *, struct vhost_virtqueue **vqs,
 long vhost_dev_set_owner(struct vhost_dev *dev);
 bool vhost_dev_has_owner(struct vhost_dev *dev);
 long vhost_dev_check_owner(struct vhost_dev *);
-struct vhost_umem *vhost_dev_reset_owner_prepare(void);
-void vhost_dev_reset_owner(struct vhost_dev *, struct vhost_umem *);
+struct vhost_iotlb *vhost_dev_reset_owner_prepare(void);
+void vhost_dev_reset_owner(struct vhost_dev *dev, struct vhost_iotlb *iotlb);
 void vhost_dev_cleanup(struct vhost_dev *);
 void vhost_dev_stop(struct vhost_dev *);
 long vhost_dev_ioctl(struct vhost_dev *, unsigned int ioctl, void __user *argp);
@@ -233,6 +213,9 @@ ssize_t vhost_chr_write_iter(struct vhost_dev *dev,
 			     struct iov_iter *from);
 int vhost_init_device_iotlb(struct vhost_dev *d, bool enabled);
 
+void vhost_iotlb_map_free(struct vhost_iotlb *iotlb,
+			  struct vhost_iotlb_map *map);
+
 #define vq_err(vq, fmt, ...) do {                                  \
 		pr_debug(pr_fmt(fmt), ##__VA_ARGS__);       \
 		if ((vq)->error_ctx)                               \
diff --git a/include/linux/vhost_iotlb.h b/include/linux/vhost_iotlb.h
new file mode 100644
index 000000000000..6b09b786a762
--- /dev/null
+++ b/include/linux/vhost_iotlb.h
@@ -0,0 +1,47 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _LINUX_VHOST_IOTLB_H
+#define _LINUX_VHOST_IOTLB_H
+
+#include <linux/interval_tree_generic.h>
+
+struct vhost_iotlb_map {
+	struct rb_node rb;
+	struct list_head link;
+	u64 start;
+	u64 last;
+	u64 size;
+	u64 addr;
+#define VHOST_MAP_RO 0x1
+#define VHOST_MAP_WO 0x2
+#define VHOST_MAP_RW 0x3
+	u32 perm;
+	u32 flags_padding;
+	u64 __subtree_last;
+};
+
+#define VHOST_IOTLB_FLAG_RETIRE 0x1
+
+struct vhost_iotlb {
+	struct rb_root_cached root;
+	struct list_head list;
+	unsigned int limit;
+	unsigned int nmaps;
+	unsigned int flags;
+};
+
+int vhost_iotlb_add_range(struct vhost_iotlb *iotlb, u64 start, u64 last,
+			  u64 addr, unsigned int perm);
+void vhost_iotlb_del_range(struct vhost_iotlb *iotlb, u64 start, u64 last);
+
+struct vhost_iotlb *vhost_iotlb_alloc(unsigned int limit, unsigned int flags);
+void vhost_iotlb_free(struct vhost_iotlb *iotlb);
+void vhost_iotlb_reset(struct vhost_iotlb *iotlb);
+
+struct vhost_iotlb_map *
+vhost_iotlb_itree_first(struct vhost_iotlb *iotlb, u64 start, u64 last);
+struct vhost_iotlb_map *
+vhost_iotlb_itree_next(struct vhost_iotlb_map *map, u64 start, u64 last);
+
+void vhost_iotlb_map_free(struct vhost_iotlb *iotlb,
+			  struct vhost_iotlb_map *map);
+#endif
-- 
2.20.1


^ permalink raw reply	[flat|nested] 38+ messages in thread

* [PATCH V9 4/9] vringh: IOTLB support
  2020-03-26 14:01 [PATCH V9 0/9] vDPA support Jason Wang
                   ` (2 preceding siblings ...)
  2020-03-26 14:01 ` [PATCH V9 3/9] vhost: factor out IOTLB Jason Wang
@ 2020-03-26 14:01 ` Jason Wang
  2020-03-26 14:01 ` [PATCH V9 5/9] vDPA: introduce vDPA bus Jason Wang
                   ` (5 subsequent siblings)
  9 siblings, 0 replies; 38+ messages in thread
From: Jason Wang @ 2020-03-26 14:01 UTC (permalink / raw)
  To: mst, linux-kernel, kvm, virtualization, netdev
  Cc: jgg, maxime.coquelin, cunming.liang, zhihong.wang, rob.miller,
	xiao.w.wang, lingshan.zhu, eperezma, lulu, parav, kevin.tian,
	stefanha, rdunlap, hch, aadam, jiri, shahafs, hanand, mhabets,
	gdawar, saugatm, vmireyno, zhangweining, Jason Wang

This patch implements the third memory accessor for vringh besides
current kernel and userspace accessors. This idea is to allow vringh
to do the address translation through an IOTLB which is implemented
via vhost_map interval tree. Users should setup and IOVA to PA mapping
in this IOTLB.

This allows us to:

- Use vringh to access virtqueues with vIOMMU
- Use vringh to implement software virtqueues for vDPA devices

Signed-off-by: Jason Wang <jasowang@redhat.com>
---
 drivers/vhost/Kconfig  |   1 +
 drivers/vhost/vringh.c | 421 ++++++++++++++++++++++++++++++++++++++---
 include/linux/vringh.h |  36 ++++
 3 files changed, 435 insertions(+), 23 deletions(-)

diff --git a/drivers/vhost/Kconfig b/drivers/vhost/Kconfig
index 2f6c2105b953..b03872886901 100644
--- a/drivers/vhost/Kconfig
+++ b/drivers/vhost/Kconfig
@@ -6,6 +6,7 @@ config VHOST_IOTLB
 
 config VHOST_RING
 	tristate
+	select VHOST_IOTLB
 	help
 	  This option is selected by any driver which needs to access
 	  the host side of a virtio ring.
diff --git a/drivers/vhost/vringh.c b/drivers/vhost/vringh.c
index a0a2d74967ef..ee0491f579ac 100644
--- a/drivers/vhost/vringh.c
+++ b/drivers/vhost/vringh.c
@@ -13,6 +13,9 @@
 #include <linux/uaccess.h>
 #include <linux/slab.h>
 #include <linux/export.h>
+#include <linux/bvec.h>
+#include <linux/highmem.h>
+#include <linux/vhost_iotlb.h>
 #include <uapi/linux/virtio_config.h>
 
 static __printf(1,2) __cold void vringh_bad(const char *fmt, ...)
@@ -71,9 +74,11 @@ static inline int __vringh_get_head(const struct vringh *vrh,
 }
 
 /* Copy some bytes to/from the iovec.  Returns num copied. */
-static inline ssize_t vringh_iov_xfer(struct vringh_kiov *iov,
+static inline ssize_t vringh_iov_xfer(struct vringh *vrh,
+				      struct vringh_kiov *iov,
 				      void *ptr, size_t len,
-				      int (*xfer)(void *addr, void *ptr,
+				      int (*xfer)(const struct vringh *vrh,
+						  void *addr, void *ptr,
 						  size_t len))
 {
 	int err, done = 0;
@@ -82,7 +87,7 @@ static inline ssize_t vringh_iov_xfer(struct vringh_kiov *iov,
 		size_t partlen;
 
 		partlen = min(iov->iov[iov->i].iov_len, len);
-		err = xfer(iov->iov[iov->i].iov_base, ptr, partlen);
+		err = xfer(vrh, iov->iov[iov->i].iov_base, ptr, partlen);
 		if (err)
 			return err;
 		done += partlen;
@@ -96,6 +101,7 @@ static inline ssize_t vringh_iov_xfer(struct vringh_kiov *iov,
 			/* Fix up old iov element then increment. */
 			iov->iov[iov->i].iov_len = iov->consumed;
 			iov->iov[iov->i].iov_base -= iov->consumed;
+
 			
 			iov->consumed = 0;
 			iov->i++;
@@ -227,7 +233,8 @@ static int slow_copy(struct vringh *vrh, void *dst, const void *src,
 				      u64 addr,
 				      struct vringh_range *r),
 		     struct vringh_range *range,
-		     int (*copy)(void *dst, const void *src, size_t len))
+		     int (*copy)(const struct vringh *vrh,
+				 void *dst, const void *src, size_t len))
 {
 	size_t part, len = sizeof(struct vring_desc);
 
@@ -241,7 +248,7 @@ static int slow_copy(struct vringh *vrh, void *dst, const void *src,
 		if (!rcheck(vrh, addr, &part, range, getrange))
 			return -EINVAL;
 
-		err = copy(dst, src, part);
+		err = copy(vrh, dst, src, part);
 		if (err)
 			return err;
 
@@ -262,7 +269,8 @@ __vringh_iov(struct vringh *vrh, u16 i,
 					     struct vringh_range *)),
 	     bool (*getrange)(struct vringh *, u64, struct vringh_range *),
 	     gfp_t gfp,
-	     int (*copy)(void *dst, const void *src, size_t len))
+	     int (*copy)(const struct vringh *vrh,
+			 void *dst, const void *src, size_t len))
 {
 	int err, count = 0, up_next, desc_max;
 	struct vring_desc desc, *descs;
@@ -291,7 +299,7 @@ __vringh_iov(struct vringh *vrh, u16 i,
 			err = slow_copy(vrh, &desc, &descs[i], rcheck, getrange,
 					&slowrange, copy);
 		else
-			err = copy(&desc, &descs[i], sizeof(desc));
+			err = copy(vrh, &desc, &descs[i], sizeof(desc));
 		if (unlikely(err))
 			goto fail;
 
@@ -404,7 +412,8 @@ static inline int __vringh_complete(struct vringh *vrh,
 				    unsigned int num_used,
 				    int (*putu16)(const struct vringh *vrh,
 						  __virtio16 *p, u16 val),
-				    int (*putused)(struct vring_used_elem *dst,
+				    int (*putused)(const struct vringh *vrh,
+						   struct vring_used_elem *dst,
 						   const struct vring_used_elem
 						   *src, unsigned num))
 {
@@ -420,12 +429,12 @@ static inline int __vringh_complete(struct vringh *vrh,
 	/* Compiler knows num_used == 1 sometimes, hence extra check */
 	if (num_used > 1 && unlikely(off + num_used >= vrh->vring.num)) {
 		u16 part = vrh->vring.num - off;
-		err = putused(&used_ring->ring[off], used, part);
+		err = putused(vrh, &used_ring->ring[off], used, part);
 		if (!err)
-			err = putused(&used_ring->ring[0], used + part,
+			err = putused(vrh, &used_ring->ring[0], used + part,
 				      num_used - part);
 	} else
-		err = putused(&used_ring->ring[off], used, num_used);
+		err = putused(vrh, &used_ring->ring[off], used, num_used);
 
 	if (err) {
 		vringh_bad("Failed to write %u used entries %u at %p",
@@ -564,13 +573,15 @@ static inline int putu16_user(const struct vringh *vrh, __virtio16 *p, u16 val)
 	return put_user(v, (__force __virtio16 __user *)p);
 }
 
-static inline int copydesc_user(void *dst, const void *src, size_t len)
+static inline int copydesc_user(const struct vringh *vrh,
+				void *dst, const void *src, size_t len)
 {
 	return copy_from_user(dst, (__force void __user *)src, len) ?
 		-EFAULT : 0;
 }
 
-static inline int putused_user(struct vring_used_elem *dst,
+static inline int putused_user(const struct vringh *vrh,
+			       struct vring_used_elem *dst,
 			       const struct vring_used_elem *src,
 			       unsigned int num)
 {
@@ -578,13 +589,15 @@ static inline int putused_user(struct vring_used_elem *dst,
 			    sizeof(*dst) * num) ? -EFAULT : 0;
 }
 
-static inline int xfer_from_user(void *src, void *dst, size_t len)
+static inline int xfer_from_user(const struct vringh *vrh, void *src,
+				 void *dst, size_t len)
 {
 	return copy_from_user(dst, (__force void __user *)src, len) ?
 		-EFAULT : 0;
 }
 
-static inline int xfer_to_user(void *dst, void *src, size_t len)
+static inline int xfer_to_user(const struct vringh *vrh,
+			       void *dst, void *src, size_t len)
 {
 	return copy_to_user((__force void __user *)dst, src, len) ?
 		-EFAULT : 0;
@@ -706,7 +719,7 @@ EXPORT_SYMBOL(vringh_getdesc_user);
  */
 ssize_t vringh_iov_pull_user(struct vringh_iov *riov, void *dst, size_t len)
 {
-	return vringh_iov_xfer((struct vringh_kiov *)riov,
+	return vringh_iov_xfer(NULL, (struct vringh_kiov *)riov,
 			       dst, len, xfer_from_user);
 }
 EXPORT_SYMBOL(vringh_iov_pull_user);
@@ -722,7 +735,7 @@ EXPORT_SYMBOL(vringh_iov_pull_user);
 ssize_t vringh_iov_push_user(struct vringh_iov *wiov,
 			     const void *src, size_t len)
 {
-	return vringh_iov_xfer((struct vringh_kiov *)wiov,
+	return vringh_iov_xfer(NULL, (struct vringh_kiov *)wiov,
 			       (void *)src, len, xfer_to_user);
 }
 EXPORT_SYMBOL(vringh_iov_push_user);
@@ -832,13 +845,15 @@ static inline int putu16_kern(const struct vringh *vrh, __virtio16 *p, u16 val)
 	return 0;
 }
 
-static inline int copydesc_kern(void *dst, const void *src, size_t len)
+static inline int copydesc_kern(const struct vringh *vrh,
+				void *dst, const void *src, size_t len)
 {
 	memcpy(dst, src, len);
 	return 0;
 }
 
-static inline int putused_kern(struct vring_used_elem *dst,
+static inline int putused_kern(const struct vringh *vrh,
+			       struct vring_used_elem *dst,
 			       const struct vring_used_elem *src,
 			       unsigned int num)
 {
@@ -846,13 +861,15 @@ static inline int putused_kern(struct vring_used_elem *dst,
 	return 0;
 }
 
-static inline int xfer_kern(void *src, void *dst, size_t len)
+static inline int xfer_kern(const struct vringh *vrh, void *src,
+			    void *dst, size_t len)
 {
 	memcpy(dst, src, len);
 	return 0;
 }
 
-static inline int kern_xfer(void *dst, void *src, size_t len)
+static inline int kern_xfer(const struct vringh *vrh, void *dst,
+			    void *src, size_t len)
 {
 	memcpy(dst, src, len);
 	return 0;
@@ -949,7 +966,7 @@ EXPORT_SYMBOL(vringh_getdesc_kern);
  */
 ssize_t vringh_iov_pull_kern(struct vringh_kiov *riov, void *dst, size_t len)
 {
-	return vringh_iov_xfer(riov, dst, len, xfer_kern);
+	return vringh_iov_xfer(NULL, riov, dst, len, xfer_kern);
 }
 EXPORT_SYMBOL(vringh_iov_pull_kern);
 
@@ -964,7 +981,7 @@ EXPORT_SYMBOL(vringh_iov_pull_kern);
 ssize_t vringh_iov_push_kern(struct vringh_kiov *wiov,
 			     const void *src, size_t len)
 {
-	return vringh_iov_xfer(wiov, (void *)src, len, kern_xfer);
+	return vringh_iov_xfer(NULL, wiov, (void *)src, len, kern_xfer);
 }
 EXPORT_SYMBOL(vringh_iov_push_kern);
 
@@ -1042,4 +1059,362 @@ int vringh_need_notify_kern(struct vringh *vrh)
 }
 EXPORT_SYMBOL(vringh_need_notify_kern);
 
+static int iotlb_translate(const struct vringh *vrh,
+			   u64 addr, u64 len, struct bio_vec iov[],
+			   int iov_size, u32 perm)
+{
+	struct vhost_iotlb_map *map;
+	struct vhost_iotlb *iotlb = vrh->iotlb;
+	int ret = 0;
+	u64 s = 0;
+
+	while (len > s) {
+		u64 size, pa, pfn;
+
+		if (unlikely(ret >= iov_size)) {
+			ret = -ENOBUFS;
+			break;
+		}
+
+		map = vhost_iotlb_itree_first(iotlb, addr,
+					      addr + len - 1);
+		if (!map || map->start > addr) {
+			ret = -EINVAL;
+			break;
+		} else if (!(map->perm & perm)) {
+			ret = -EPERM;
+			break;
+		}
+
+		size = map->size - addr + map->start;
+		pa = map->addr + addr - map->start;
+		pfn = pa >> PAGE_SHIFT;
+		iov[ret].bv_page = pfn_to_page(pfn);
+		iov[ret].bv_len = min(len - s, size);
+		iov[ret].bv_offset = pa & (PAGE_SIZE - 1);
+		s += size;
+		addr += size;
+		++ret;
+	}
+
+	return ret;
+}
+
+static inline int copy_from_iotlb(const struct vringh *vrh, void *dst,
+				  void *src, size_t len)
+{
+	struct iov_iter iter;
+	struct bio_vec iov[16];
+	int ret;
+
+	ret = iotlb_translate(vrh, (u64)(uintptr_t)src,
+			      len, iov, 16, VHOST_MAP_RO);
+	if (ret < 0)
+		return ret;
+
+	iov_iter_bvec(&iter, READ, iov, ret, len);
+
+	ret = copy_from_iter(dst, len, &iter);
+
+	return ret;
+}
+
+static inline int copy_to_iotlb(const struct vringh *vrh, void *dst,
+				void *src, size_t len)
+{
+	struct iov_iter iter;
+	struct bio_vec iov[16];
+	int ret;
+
+	ret = iotlb_translate(vrh, (u64)(uintptr_t)dst,
+			      len, iov, 16, VHOST_MAP_WO);
+	if (ret < 0)
+		return ret;
+
+	iov_iter_bvec(&iter, WRITE, iov, ret, len);
+
+	return copy_to_iter(src, len, &iter);
+}
+
+static inline int getu16_iotlb(const struct vringh *vrh,
+			       u16 *val, const __virtio16 *p)
+{
+	struct bio_vec iov;
+	void *kaddr, *from;
+	int ret;
+
+	/* Atomic read is needed for getu16 */
+	ret = iotlb_translate(vrh, (u64)(uintptr_t)p, sizeof(*p),
+			      &iov, 1, VHOST_MAP_RO);
+	if (ret < 0)
+		return ret;
+
+	kaddr = kmap_atomic(iov.bv_page);
+	from = kaddr + iov.bv_offset;
+	*val = vringh16_to_cpu(vrh, READ_ONCE(*(__virtio16 *)from));
+	kunmap_atomic(kaddr);
+
+	return 0;
+}
+
+static inline int putu16_iotlb(const struct vringh *vrh,
+			       __virtio16 *p, u16 val)
+{
+	struct bio_vec iov;
+	void *kaddr, *to;
+	int ret;
+
+	/* Atomic write is needed for putu16 */
+	ret = iotlb_translate(vrh, (u64)(uintptr_t)p, sizeof(*p),
+			      &iov, 1, VHOST_MAP_WO);
+	if (ret < 0)
+		return ret;
+
+	kaddr = kmap_atomic(iov.bv_page);
+	to = kaddr + iov.bv_offset;
+	WRITE_ONCE(*(__virtio16 *)to, cpu_to_vringh16(vrh, val));
+	kunmap_atomic(kaddr);
+
+	return 0;
+}
+
+static inline int copydesc_iotlb(const struct vringh *vrh,
+				 void *dst, const void *src, size_t len)
+{
+	int ret;
+
+	ret = copy_from_iotlb(vrh, dst, (void *)src, len);
+	if (ret != len)
+		return -EFAULT;
+
+	return 0;
+}
+
+static inline int xfer_from_iotlb(const struct vringh *vrh, void *src,
+				  void *dst, size_t len)
+{
+	int ret;
+
+	ret = copy_from_iotlb(vrh, dst, src, len);
+	if (ret != len)
+		return -EFAULT;
+
+	return 0;
+}
+
+static inline int xfer_to_iotlb(const struct vringh *vrh,
+			       void *dst, void *src, size_t len)
+{
+	int ret;
+
+	ret = copy_to_iotlb(vrh, dst, src, len);
+	if (ret != len)
+		return -EFAULT;
+
+	return 0;
+}
+
+static inline int putused_iotlb(const struct vringh *vrh,
+				struct vring_used_elem *dst,
+				const struct vring_used_elem *src,
+				unsigned int num)
+{
+	int size = num * sizeof(*dst);
+	int ret;
+
+	ret = copy_to_iotlb(vrh, dst, (void *)src, num * sizeof(*dst));
+	if (ret != size)
+		return -EFAULT;
+
+	return 0;
+}
+
+/**
+ * vringh_init_iotlb - initialize a vringh for a ring with IOTLB.
+ * @vrh: the vringh to initialize.
+ * @features: the feature bits for this ring.
+ * @num: the number of elements.
+ * @weak_barriers: true if we only need memory barriers, not I/O.
+ * @desc: the userpace descriptor pointer.
+ * @avail: the userpace avail pointer.
+ * @used: the userpace used pointer.
+ *
+ * Returns an error if num is invalid.
+ */
+int vringh_init_iotlb(struct vringh *vrh, u64 features,
+		      unsigned int num, bool weak_barriers,
+		      struct vring_desc *desc,
+		      struct vring_avail *avail,
+		      struct vring_used *used)
+{
+	return vringh_init_kern(vrh, features, num, weak_barriers,
+				desc, avail, used);
+}
+EXPORT_SYMBOL(vringh_init_iotlb);
+
+/**
+ * vringh_set_iotlb - initialize a vringh for a ring with IOTLB.
+ * @vrh: the vring
+ * @iotlb: iotlb associated with this vring
+ */
+void vringh_set_iotlb(struct vringh *vrh, struct vhost_iotlb *iotlb)
+{
+	vrh->iotlb = iotlb;
+}
+EXPORT_SYMBOL(vringh_set_iotlb);
+
+/**
+ * vringh_getdesc_iotlb - get next available descriptor from ring with
+ * IOTLB.
+ * @vrh: the kernelspace vring.
+ * @riov: where to put the readable descriptors (or NULL)
+ * @wiov: where to put the writable descriptors (or NULL)
+ * @head: head index we received, for passing to vringh_complete_iotlb().
+ * @gfp: flags for allocating larger riov/wiov.
+ *
+ * Returns 0 if there was no descriptor, 1 if there was, or -errno.
+ *
+ * Note that on error return, you can tell the difference between an
+ * invalid ring and a single invalid descriptor: in the former case,
+ * *head will be vrh->vring.num.  You may be able to ignore an invalid
+ * descriptor, but there's not much you can do with an invalid ring.
+ *
+ * Note that you may need to clean up riov and wiov, even on error!
+ */
+int vringh_getdesc_iotlb(struct vringh *vrh,
+			 struct vringh_kiov *riov,
+			 struct vringh_kiov *wiov,
+			 u16 *head,
+			 gfp_t gfp)
+{
+	int err;
+
+	err = __vringh_get_head(vrh, getu16_iotlb, &vrh->last_avail_idx);
+	if (err < 0)
+		return err;
+
+	/* Empty... */
+	if (err == vrh->vring.num)
+		return 0;
+
+	*head = err;
+	err = __vringh_iov(vrh, *head, riov, wiov, no_range_check, NULL,
+			   gfp, copydesc_iotlb);
+	if (err)
+		return err;
+
+	return 1;
+}
+EXPORT_SYMBOL(vringh_getdesc_iotlb);
+
+/**
+ * vringh_iov_pull_iotlb - copy bytes from vring_iov.
+ * @vrh: the vring.
+ * @riov: the riov as passed to vringh_getdesc_iotlb() (updated as we consume)
+ * @dst: the place to copy.
+ * @len: the maximum length to copy.
+ *
+ * Returns the bytes copied <= len or a negative errno.
+ */
+ssize_t vringh_iov_pull_iotlb(struct vringh *vrh,
+			      struct vringh_kiov *riov,
+			      void *dst, size_t len)
+{
+	return vringh_iov_xfer(vrh, riov, dst, len, xfer_from_iotlb);
+}
+EXPORT_SYMBOL(vringh_iov_pull_iotlb);
+
+/**
+ * vringh_iov_push_iotlb - copy bytes into vring_iov.
+ * @vrh: the vring.
+ * @wiov: the wiov as passed to vringh_getdesc_iotlb() (updated as we consume)
+ * @dst: the place to copy.
+ * @len: the maximum length to copy.
+ *
+ * Returns the bytes copied <= len or a negative errno.
+ */
+ssize_t vringh_iov_push_iotlb(struct vringh *vrh,
+			      struct vringh_kiov *wiov,
+			      const void *src, size_t len)
+{
+	return vringh_iov_xfer(vrh, wiov, (void *)src, len, xfer_to_iotlb);
+}
+EXPORT_SYMBOL(vringh_iov_push_iotlb);
+
+/**
+ * vringh_abandon_iotlb - we've decided not to handle the descriptor(s).
+ * @vrh: the vring.
+ * @num: the number of descriptors to put back (ie. num
+ *	 vringh_get_iotlb() to undo).
+ *
+ * The next vringh_get_iotlb() will return the old descriptor(s) again.
+ */
+void vringh_abandon_iotlb(struct vringh *vrh, unsigned int num)
+{
+	/* We only update vring_avail_event(vr) when we want to be notified,
+	 * so we haven't changed that yet.
+	 */
+	vrh->last_avail_idx -= num;
+}
+EXPORT_SYMBOL(vringh_abandon_iotlb);
+
+/**
+ * vringh_complete_iotlb - we've finished with descriptor, publish it.
+ * @vrh: the vring.
+ * @head: the head as filled in by vringh_getdesc_iotlb.
+ * @len: the length of data we have written.
+ *
+ * You should check vringh_need_notify_iotlb() after one or more calls
+ * to this function.
+ */
+int vringh_complete_iotlb(struct vringh *vrh, u16 head, u32 len)
+{
+	struct vring_used_elem used;
+
+	used.id = cpu_to_vringh32(vrh, head);
+	used.len = cpu_to_vringh32(vrh, len);
+
+	return __vringh_complete(vrh, &used, 1, putu16_iotlb, putused_iotlb);
+}
+EXPORT_SYMBOL(vringh_complete_iotlb);
+
+/**
+ * vringh_notify_enable_iotlb - we want to know if something changes.
+ * @vrh: the vring.
+ *
+ * This always enables notifications, but returns false if there are
+ * now more buffers available in the vring.
+ */
+bool vringh_notify_enable_iotlb(struct vringh *vrh)
+{
+	return __vringh_notify_enable(vrh, getu16_iotlb, putu16_iotlb);
+}
+EXPORT_SYMBOL(vringh_notify_enable_iotlb);
+
+/**
+ * vringh_notify_disable_iotlb - don't tell us if something changes.
+ * @vrh: the vring.
+ *
+ * This is our normal running state: we disable and then only enable when
+ * we're going to sleep.
+ */
+void vringh_notify_disable_iotlb(struct vringh *vrh)
+{
+	__vringh_notify_disable(vrh, putu16_iotlb);
+}
+EXPORT_SYMBOL(vringh_notify_disable_iotlb);
+
+/**
+ * vringh_need_notify_iotlb - must we tell the other side about used buffers?
+ * @vrh: the vring we've called vringh_complete_iotlb() on.
+ *
+ * Returns -errno or 0 if we don't need to tell the other side, 1 if we do.
+ */
+int vringh_need_notify_iotlb(struct vringh *vrh)
+{
+	return __vringh_need_notify(vrh, getu16_iotlb);
+}
+EXPORT_SYMBOL(vringh_need_notify_iotlb);
+
+
 MODULE_LICENSE("GPL");
diff --git a/include/linux/vringh.h b/include/linux/vringh.h
index d237087eb257..bd0503ca6f8f 100644
--- a/include/linux/vringh.h
+++ b/include/linux/vringh.h
@@ -14,6 +14,8 @@
 #include <linux/virtio_byteorder.h>
 #include <linux/uio.h>
 #include <linux/slab.h>
+#include <linux/dma-direction.h>
+#include <linux/vhost_iotlb.h>
 #include <asm/barrier.h>
 
 /* virtio_ring with information needed for host access. */
@@ -39,6 +41,9 @@ struct vringh {
 	/* The vring (note: it may contain user pointers!) */
 	struct vring vring;
 
+	/* IOTLB for this vring */
+	struct vhost_iotlb *iotlb;
+
 	/* The function to call to notify the guest about added buffers */
 	void (*notify)(struct vringh *);
 };
@@ -248,4 +253,35 @@ static inline __virtio64 cpu_to_vringh64(const struct vringh *vrh, u64 val)
 {
 	return __cpu_to_virtio64(vringh_is_little_endian(vrh), val);
 }
+
+void vringh_set_iotlb(struct vringh *vrh, struct vhost_iotlb *iotlb);
+
+int vringh_init_iotlb(struct vringh *vrh, u64 features,
+		      unsigned int num, bool weak_barriers,
+		      struct vring_desc *desc,
+		      struct vring_avail *avail,
+		      struct vring_used *used);
+
+int vringh_getdesc_iotlb(struct vringh *vrh,
+			 struct vringh_kiov *riov,
+			 struct vringh_kiov *wiov,
+			 u16 *head,
+			 gfp_t gfp);
+
+ssize_t vringh_iov_pull_iotlb(struct vringh *vrh,
+			      struct vringh_kiov *riov,
+			      void *dst, size_t len);
+ssize_t vringh_iov_push_iotlb(struct vringh *vrh,
+			      struct vringh_kiov *wiov,
+			      const void *src, size_t len);
+
+void vringh_abandon_iotlb(struct vringh *vrh, unsigned int num);
+
+int vringh_complete_iotlb(struct vringh *vrh, u16 head, u32 len);
+
+bool vringh_notify_enable_iotlb(struct vringh *vrh);
+void vringh_notify_disable_iotlb(struct vringh *vrh);
+
+int vringh_need_notify_iotlb(struct vringh *vrh);
+
 #endif /* _LINUX_VRINGH_H */
-- 
2.20.1


^ permalink raw reply	[flat|nested] 38+ messages in thread

* [PATCH V9 5/9] vDPA: introduce vDPA bus
  2020-03-26 14:01 [PATCH V9 0/9] vDPA support Jason Wang
                   ` (3 preceding siblings ...)
  2020-03-26 14:01 ` [PATCH V9 4/9] vringh: IOTLB support Jason Wang
@ 2020-03-26 14:01 ` Jason Wang
  2020-03-26 14:01 ` [PATCH V9 6/9] virtio: introduce a vDPA based transport Jason Wang
                   ` (4 subsequent siblings)
  9 siblings, 0 replies; 38+ messages in thread
From: Jason Wang @ 2020-03-26 14:01 UTC (permalink / raw)
  To: mst, linux-kernel, kvm, virtualization, netdev
  Cc: jgg, maxime.coquelin, cunming.liang, zhihong.wang, rob.miller,
	xiao.w.wang, lingshan.zhu, eperezma, lulu, parav, kevin.tian,
	stefanha, rdunlap, hch, aadam, jiri, shahafs, hanand, mhabets,
	gdawar, saugatm, vmireyno, zhangweining, Jason Wang

vDPA device is a device that uses a datapath which complies with the
virtio specifications with vendor specific control path. vDPA devices
can be both physically located on the hardware or emulated by
software. vDPA hardware devices are usually implemented through PCIE
with the following types:

- PF (Physical Function) - A single Physical Function
- VF (Virtual Function) - Device that supports single root I/O
  virtualization (SR-IOV). Its Virtual Function (VF) represents a
  virtualized instance of the device that can be assigned to different
  partitions
- ADI (Assignable Device Interface) and its equivalents - With
  technologies such as Intel Scalable IOV, a virtual device (VDEV)
  composed by host OS utilizing one or more ADIs. Or its equivalent
  like SF (Sub function) from Mellanox.

From a driver's perspective, depends on how and where the DMA
translation is done, vDPA devices are split into two types:

- Platform specific DMA translation - From the driver's perspective,
  the device can be used on a platform where device access to data in
  memory is limited and/or translated. An example is a PCIE vDPA whose
  DMA request was tagged via a bus (e.g PCIE) specific way. DMA
  translation and protection are done at PCIE bus IOMMU level.
- Device specific DMA translation - The device implements DMA
  isolation and protection through its own logic. An example is a vDPA
  device which uses on-chip IOMMU.

To hide the differences and complexity of the above types for a vDPA
device/IOMMU options and in order to present a generic virtio device
to the upper layer, a device agnostic framework is required.

This patch introduces a software vDPA bus which abstracts the
common attributes of vDPA device, vDPA bus driver and the
communication method (vdpa_config_ops) between the vDPA device
abstraction and the vDPA bus driver. This allows multiple types of
drivers to be used for vDPA device like the virtio_vdpa and vhost_vdpa
driver to operate on the bus and allow vDPA device could be used by
either kernel virtio driver or userspace vhost drivers as:

   virtio drivers  vhost drivers
          |             |
    [virtio bus]   [vhost uAPI]
          |             |
   virtio device   vhost device
   virtio_vdpa drv vhost_vdpa drv
             \       /
            [vDPA bus]
                 |
            vDPA device
            hardware drv
                 |
            [hardware bus]
                 |
            vDPA hardware

With the abstraction of vDPA bus and vDPA bus operations, the
difference and complexity of the under layer hardware is hidden from
upper layer. The vDPA bus drivers on top can use a unified
vdpa_config_ops to control different types of vDPA device.

Signed-off-by: Jason Wang <jasowang@redhat.com>
---
 MAINTAINERS                  |   1 +
 drivers/virtio/Kconfig       |   2 +
 drivers/virtio/Makefile      |   1 +
 drivers/virtio/vdpa/Kconfig  |   7 +
 drivers/virtio/vdpa/Makefile |   2 +
 drivers/virtio/vdpa/vdpa.c   | 180 +++++++++++++++++++++++++
 include/linux/vdpa.h         | 253 +++++++++++++++++++++++++++++++++++
 7 files changed, 446 insertions(+)
 create mode 100644 drivers/virtio/vdpa/Kconfig
 create mode 100644 drivers/virtio/vdpa/Makefile
 create mode 100644 drivers/virtio/vdpa/vdpa.c
 create mode 100644 include/linux/vdpa.h

diff --git a/MAINTAINERS b/MAINTAINERS
index 0fb645b5a7df..2b8d9fa38d9a 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -17701,6 +17701,7 @@ F:	tools/virtio/
 F:	drivers/net/virtio_net.c
 F:	drivers/block/virtio_blk.c
 F:	include/linux/virtio*.h
+F:	include/linux/vdpa.h
 F:	include/uapi/linux/virtio_*.h
 F:	drivers/crypto/virtio/
 F:	mm/balloon_compaction.c
diff --git a/drivers/virtio/Kconfig b/drivers/virtio/Kconfig
index 078615cf2afc..9c4fdb64d9ac 100644
--- a/drivers/virtio/Kconfig
+++ b/drivers/virtio/Kconfig
@@ -96,3 +96,5 @@ config VIRTIO_MMIO_CMDLINE_DEVICES
 	 If unsure, say 'N'.
 
 endif # VIRTIO_MENU
+
+source "drivers/virtio/vdpa/Kconfig"
diff --git a/drivers/virtio/Makefile b/drivers/virtio/Makefile
index 3a2b5c5dcf46..fdf5eacd0d0a 100644
--- a/drivers/virtio/Makefile
+++ b/drivers/virtio/Makefile
@@ -6,3 +6,4 @@ virtio_pci-y := virtio_pci_modern.o virtio_pci_common.o
 virtio_pci-$(CONFIG_VIRTIO_PCI_LEGACY) += virtio_pci_legacy.o
 obj-$(CONFIG_VIRTIO_BALLOON) += virtio_balloon.o
 obj-$(CONFIG_VIRTIO_INPUT) += virtio_input.o
+obj-$(CONFIG_VDPA) += vdpa/
diff --git a/drivers/virtio/vdpa/Kconfig b/drivers/virtio/vdpa/Kconfig
new file mode 100644
index 000000000000..351617723d12
--- /dev/null
+++ b/drivers/virtio/vdpa/Kconfig
@@ -0,0 +1,7 @@
+# SPDX-License-Identifier: GPL-2.0-only
+config VDPA
+	tristate
+	help
+	  Enable this module to support vDPA device that uses a
+	  datapath which complies with virtio specifications with
+	  vendor specific control path.
diff --git a/drivers/virtio/vdpa/Makefile b/drivers/virtio/vdpa/Makefile
new file mode 100644
index 000000000000..ee6a35e8a4fb
--- /dev/null
+++ b/drivers/virtio/vdpa/Makefile
@@ -0,0 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0
+obj-$(CONFIG_VDPA) += vdpa.o
diff --git a/drivers/virtio/vdpa/vdpa.c b/drivers/virtio/vdpa/vdpa.c
new file mode 100644
index 000000000000..e9ed6a2b635b
--- /dev/null
+++ b/drivers/virtio/vdpa/vdpa.c
@@ -0,0 +1,180 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * vDPA bus.
+ *
+ * Copyright (c) 2020, Red Hat. All rights reserved.
+ *     Author: Jason Wang <jasowang@redhat.com>
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/idr.h>
+#include <linux/slab.h>
+#include <linux/vdpa.h>
+
+static DEFINE_IDA(vdpa_index_ida);
+
+static int vdpa_dev_probe(struct device *d)
+{
+	struct vdpa_device *vdev = dev_to_vdpa(d);
+	struct vdpa_driver *drv = drv_to_vdpa(vdev->dev.driver);
+	int ret = 0;
+
+	if (drv && drv->probe)
+		ret = drv->probe(vdev);
+
+	return ret;
+}
+
+static int vdpa_dev_remove(struct device *d)
+{
+	struct vdpa_device *vdev = dev_to_vdpa(d);
+	struct vdpa_driver *drv = drv_to_vdpa(vdev->dev.driver);
+
+	if (drv && drv->remove)
+		drv->remove(vdev);
+
+	return 0;
+}
+
+static struct bus_type vdpa_bus = {
+	.name  = "vdpa",
+	.probe = vdpa_dev_probe,
+	.remove = vdpa_dev_remove,
+};
+
+static void vdpa_release_dev(struct device *d)
+{
+	struct vdpa_device *vdev = dev_to_vdpa(d);
+	const struct vdpa_config_ops *ops = vdev->config;
+
+	if (ops->free)
+		ops->free(vdev);
+
+	ida_simple_remove(&vdpa_index_ida, vdev->index);
+	kfree(vdev);
+}
+
+/**
+ * __vdpa_alloc_device - allocate and initilaize a vDPA device
+ * This allows driver to some prepartion after device is
+ * initialized but before registered.
+ * @parent: the parent device
+ * @config: the bus operations that is supported by this device
+ * @size: size of the parent structure that contains private data
+ *
+ * Drvier should use vdap_alloc_device() wrapper macro instead of
+ * using this directly.
+ *
+ * Returns an error when parent/config/dma_dev is not set or fail to get
+ * ida.
+ */
+struct vdpa_device *__vdpa_alloc_device(struct device *parent,
+					const struct vdpa_config_ops *config,
+					size_t size)
+{
+	struct vdpa_device *vdev;
+	int err = -EINVAL;
+
+	if (!config)
+		goto err;
+
+	if (!!config->dma_map != !!config->dma_unmap)
+		goto err;
+
+	err = -ENOMEM;
+	vdev = kzalloc(size, GFP_KERNEL);
+	if (!vdev)
+		goto err;
+
+	err = ida_simple_get(&vdpa_index_ida, 0, 0, GFP_KERNEL);
+	if (err < 0)
+		goto err_ida;
+
+	vdev->dev.bus = &vdpa_bus;
+	vdev->dev.parent = parent;
+	vdev->dev.release = vdpa_release_dev;
+	vdev->index = err;
+	vdev->config = config;
+
+	err = dev_set_name(&vdev->dev, "vdpa%u", vdev->index);
+	if (err)
+		goto err_name;
+
+	device_initialize(&vdev->dev);
+
+	return vdev;
+
+err_name:
+	ida_simple_remove(&vdpa_index_ida, vdev->index);
+err_ida:
+	kfree(vdev);
+err:
+	return ERR_PTR(err);
+}
+EXPORT_SYMBOL_GPL(__vdpa_alloc_device);
+
+/**
+ * vdpa_register_device - register a vDPA device
+ * Callers must have a succeed call of vdpa_init_device() before.
+ * @vdev: the vdpa device to be registered to vDPA bus
+ *
+ * Returns an error when fail to add to vDPA bus
+ */
+int vdpa_register_device(struct vdpa_device *vdev)
+{
+	return device_add(&vdev->dev);
+}
+EXPORT_SYMBOL_GPL(vdpa_register_device);
+
+/**
+ * vdpa_unregister_device - unregister a vDPA device
+ * @vdev: the vdpa device to be unregisted from vDPA bus
+ */
+void vdpa_unregister_device(struct vdpa_device *vdev)
+{
+	device_unregister(&vdev->dev);
+}
+EXPORT_SYMBOL_GPL(vdpa_unregister_device);
+
+/**
+ * __vdpa_register_driver - register a vDPA device driver
+ * @drv: the vdpa device driver to be registered
+ * @owner: module owner of the driver
+ *
+ * Returns an err when fail to do the registration
+ */
+int __vdpa_register_driver(struct vdpa_driver *drv, struct module *owner)
+{
+	drv->driver.bus = &vdpa_bus;
+	drv->driver.owner = owner;
+
+	return driver_register(&drv->driver);
+}
+EXPORT_SYMBOL_GPL(__vdpa_register_driver);
+
+/**
+ * vdpa_unregister_driver - unregister a vDPA device driver
+ * @drv: the vdpa device driver to be unregistered
+ */
+void vdpa_unregister_driver(struct vdpa_driver *drv)
+{
+	driver_unregister(&drv->driver);
+}
+EXPORT_SYMBOL_GPL(vdpa_unregister_driver);
+
+static int vdpa_init(void)
+{
+	return bus_register(&vdpa_bus);
+}
+
+static void __exit vdpa_exit(void)
+{
+	bus_unregister(&vdpa_bus);
+	ida_destroy(&vdpa_index_ida);
+}
+core_initcall(vdpa_init);
+module_exit(vdpa_exit);
+
+MODULE_AUTHOR("Jason Wang <jasowang@redhat.com>");
+MODULE_LICENSE("GPL v2");
diff --git a/include/linux/vdpa.h b/include/linux/vdpa.h
new file mode 100644
index 000000000000..733acfb7ef84
--- /dev/null
+++ b/include/linux/vdpa.h
@@ -0,0 +1,253 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _LINUX_VDPA_H
+#define _LINUX_VDPA_H
+
+#include <linux/kernel.h>
+#include <linux/device.h>
+#include <linux/interrupt.h>
+#include <linux/vhost_iotlb.h>
+
+/**
+ * vDPA callback definition.
+ * @callback: interrupt callback function
+ * @private: the data passed to the callback function
+ */
+struct vdpa_callback {
+	irqreturn_t (*callback)(void *data);
+	void *private;
+};
+
+/**
+ * vDPA device - representation of a vDPA device
+ * @dev: underlying device
+ * @dma_dev: the actual device that is performing DMA
+ * @config: the configuration ops for this device.
+ * @index: device index
+ */
+struct vdpa_device {
+	struct device dev;
+	struct device *dma_dev;
+	const struct vdpa_config_ops *config;
+	unsigned int index;
+};
+
+/**
+ * vDPA_config_ops - operations for configuring a vDPA device.
+ * Note: vDPA device drivers are required to implement all of the
+ * operations unless it is mentioned to be optional in the following
+ * list.
+ *
+ * @set_vq_address:		Set the address of virtqueue
+ *				@vdev: vdpa device
+ *				@idx: virtqueue index
+ *				@desc_area: address of desc area
+ *				@driver_area: address of driver area
+ *				@device_area: address of device area
+ *				Returns integer: success (0) or error (< 0)
+ * @set_vq_num:			Set the size of virtqueue
+ *				@vdev: vdpa device
+ *				@idx: virtqueue index
+ *				@num: the size of virtqueue
+ * @kick_vq:			Kick the virtqueue
+ *				@vdev: vdpa device
+ *				@idx: virtqueue index
+ * @set_vq_cb:			Set the interrupt callback function for
+ *				a virtqueue
+ *				@vdev: vdpa device
+ *				@idx: virtqueue index
+ *				@cb: virtio-vdev interrupt callback structure
+ * @set_vq_ready:		Set ready status for a virtqueue
+ *				@vdev: vdpa device
+ *				@idx: virtqueue index
+ *				@ready: ready (true) not ready(false)
+ * @get_vq_ready:		Get ready status for a virtqueue
+ *				@vdev: vdpa device
+ *				@idx: virtqueue index
+ *				Returns boolean: ready (true) or not (false)
+ * @set_vq_state:		Set the state for a virtqueue
+ *				@vdev: vdpa device
+ *				@idx: virtqueue index
+ *				@state: virtqueue state (last_avail_idx)
+ *				Returns integer: success (0) or error (< 0)
+ * @get_vq_state:		Get the state for a virtqueue
+ *				@vdev: vdpa device
+ *				@idx: virtqueue index
+ *				Returns virtqueue state (last_avail_idx)
+ * @get_vq_align:		Get the virtqueue align requirement
+ *				for the device
+ *				@vdev: vdpa device
+ *				Returns virtqueue algin requirement
+ * @get_features:		Get virtio features supported by the device
+ *				@vdev: vdpa device
+ *				Returns the virtio features support by the
+ *				device
+ * @set_features:		Set virtio features supported by the driver
+ *				@vdev: vdpa device
+ *				@features: feature support by the driver
+ *				Returns integer: success (0) or error (< 0)
+ * @set_config_cb:		Set the config interrupt callback
+ *				@vdev: vdpa device
+ *				@cb: virtio-vdev interrupt callback structure
+ * @get_vq_num_max:		Get the max size of virtqueue
+ *				@vdev: vdpa device
+ *				Returns u16: max size of virtqueue
+ * @get_device_id:		Get virtio device id
+ *				@vdev: vdpa device
+ *				Returns u32: virtio device id
+ * @get_vendor_id:		Get id for the vendor that provides this device
+ *				@vdev: vdpa device
+ *				Returns u32: virtio vendor id
+ * @get_status:			Get the device status
+ *				@vdev: vdpa device
+ *				Returns u8: virtio device status
+ * @set_status:			Set the device status
+ *				@vdev: vdpa device
+ *				@status: virtio device status
+ * @get_config:			Read from device specific configuration space
+ *				@vdev: vdpa device
+ *				@offset: offset from the beginning of
+ *				configuration space
+ *				@buf: buffer used to read to
+ *				@len: the length to read from
+ *				configuration space
+ * @set_config:			Write to device specific configuration space
+ *				@vdev: vdpa device
+ *				@offset: offset from the beginning of
+ *				configuration space
+ *				@buf: buffer used to write from
+ *				@len: the length to write to
+ *				configuration space
+ * @get_generation:		Get device config generation (optional)
+ *				@vdev: vdpa device
+ *				Returns u32: device generation
+ * @set_map:			Set device memory mapping (optional)
+ *				Needed for device that using device
+ *				specific DMA translation (on-chip IOMMU)
+ *				@vdev: vdpa device
+ *				@iotlb: vhost memory mapping to be
+ *				used by the vDPA
+ *				Returns integer: success (0) or error (< 0)
+ * @dma_map:			Map an area of PA to IOVA (optional)
+ *				Needed for device that using device
+ *				specific DMA translation (on-chip IOMMU)
+ *				and preferring incremental map.
+ *				@vdev: vdpa device
+ *				@iova: iova to be mapped
+ *				@size: size of the area
+ *				@pa: physical address for the map
+ *				@perm: device access permission (VHOST_MAP_XX)
+ *				Returns integer: success (0) or error (< 0)
+ * @dma_unmap:			Unmap an area of IOVA (optional but
+ *				must be implemented with dma_map)
+ *				Needed for device that using device
+ *				specific DMA translation (on-chip IOMMU)
+ *				and preferring incremental unmap.
+ *				@vdev: vdpa device
+ *				@iova: iova to be unmapped
+ *				@size: size of the area
+ *				Returns integer: success (0) or error (< 0)
+ * @free:			Free resources that belongs to vDPA (optional)
+ *				@vdev: vdpa device
+ */
+struct vdpa_config_ops {
+	/* Virtqueue ops */
+	int (*set_vq_address)(struct vdpa_device *vdev,
+			      u16 idx, u64 desc_area, u64 driver_area,
+			      u64 device_area);
+	void (*set_vq_num)(struct vdpa_device *vdev, u16 idx, u32 num);
+	void (*kick_vq)(struct vdpa_device *vdev, u16 idx);
+	void (*set_vq_cb)(struct vdpa_device *vdev, u16 idx,
+			  struct vdpa_callback *cb);
+	void (*set_vq_ready)(struct vdpa_device *vdev, u16 idx, bool ready);
+	bool (*get_vq_ready)(struct vdpa_device *vdev, u16 idx);
+	int (*set_vq_state)(struct vdpa_device *vdev, u16 idx, u64 state);
+	u64 (*get_vq_state)(struct vdpa_device *vdev, u16 idx);
+
+	/* Device ops */
+	u16 (*get_vq_align)(struct vdpa_device *vdev);
+	u64 (*get_features)(struct vdpa_device *vdev);
+	int (*set_features)(struct vdpa_device *vdev, u64 features);
+	void (*set_config_cb)(struct vdpa_device *vdev,
+			      struct vdpa_callback *cb);
+	u16 (*get_vq_num_max)(struct vdpa_device *vdev);
+	u32 (*get_device_id)(struct vdpa_device *vdev);
+	u32 (*get_vendor_id)(struct vdpa_device *vdev);
+	u8 (*get_status)(struct vdpa_device *vdev);
+	void (*set_status)(struct vdpa_device *vdev, u8 status);
+	void (*get_config)(struct vdpa_device *vdev, unsigned int offset,
+			   void *buf, unsigned int len);
+	void (*set_config)(struct vdpa_device *vdev, unsigned int offset,
+			   const void *buf, unsigned int len);
+	u32 (*get_generation)(struct vdpa_device *vdev);
+
+	/* DMA ops */
+	int (*set_map)(struct vdpa_device *vdev, struct vhost_iotlb *iotlb);
+	int (*dma_map)(struct vdpa_device *vdev, u64 iova, u64 size,
+		       u64 pa, u32 perm);
+	int (*dma_unmap)(struct vdpa_device *vdev, u64 iova, u64 size);
+
+	/* Free device resources */
+	void (*free)(struct vdpa_device *vdev);
+};
+
+struct vdpa_device *__vdpa_alloc_device(struct device *parent,
+					const struct vdpa_config_ops *config,
+					size_t size);
+
+#define vdpa_alloc_device(dev_struct, member, parent, config)   \
+			  container_of(__vdpa_alloc_device( \
+				       parent, config, \
+				       sizeof(dev_struct) + \
+				       BUILD_BUG_ON_ZERO(offsetof( \
+				       dev_struct, member))), \
+				       dev_struct, member)
+
+int vdpa_register_device(struct vdpa_device *vdev);
+void vdpa_unregister_device(struct vdpa_device *vdev);
+
+/**
+ * vdpa_driver - operations for a vDPA driver
+ * @driver: underlying device driver
+ * @probe: the function to call when a device is found.  Returns 0 or -errno.
+ * @remove: the function to call when a device is removed.
+ */
+struct vdpa_driver {
+	struct device_driver driver;
+	int (*probe)(struct vdpa_device *vdev);
+	void (*remove)(struct vdpa_device *vdev);
+};
+
+#define vdpa_register_driver(drv) \
+	__vdpa_register_driver(drv, THIS_MODULE)
+int __vdpa_register_driver(struct vdpa_driver *drv, struct module *owner);
+void vdpa_unregister_driver(struct vdpa_driver *drv);
+
+#define module_vdpa_driver(__vdpa_driver) \
+	module_driver(__vdpa_driver, vdpa_register_driver,	\
+		      vdpa_unregister_driver)
+
+static inline struct vdpa_driver *drv_to_vdpa(struct device_driver *driver)
+{
+	return container_of(driver, struct vdpa_driver, driver);
+}
+
+static inline struct vdpa_device *dev_to_vdpa(struct device *_dev)
+{
+	return container_of(_dev, struct vdpa_device, dev);
+}
+
+static inline void *vdpa_get_drvdata(const struct vdpa_device *vdev)
+{
+	return dev_get_drvdata(&vdev->dev);
+}
+
+static inline void vdpa_set_drvdata(struct vdpa_device *vdev, void *data)
+{
+	dev_set_drvdata(&vdev->dev, data);
+}
+
+static inline struct device *vdpa_get_dma_dev(struct vdpa_device *vdev)
+{
+	return vdev->dma_dev;
+}
+#endif /* _LINUX_VDPA_H */
-- 
2.20.1


^ permalink raw reply	[flat|nested] 38+ messages in thread

* [PATCH V9 6/9] virtio: introduce a vDPA based transport
  2020-03-26 14:01 [PATCH V9 0/9] vDPA support Jason Wang
                   ` (4 preceding siblings ...)
  2020-03-26 14:01 ` [PATCH V9 5/9] vDPA: introduce vDPA bus Jason Wang
@ 2020-03-26 14:01 ` Jason Wang
  2020-03-26 14:01 ` [PATCH V9 7/9] vhost: introduce vDPA-based backend Jason Wang
                   ` (3 subsequent siblings)
  9 siblings, 0 replies; 38+ messages in thread
From: Jason Wang @ 2020-03-26 14:01 UTC (permalink / raw)
  To: mst, linux-kernel, kvm, virtualization, netdev
  Cc: jgg, maxime.coquelin, cunming.liang, zhihong.wang, rob.miller,
	xiao.w.wang, lingshan.zhu, eperezma, lulu, parav, kevin.tian,
	stefanha, rdunlap, hch, aadam, jiri, shahafs, hanand, mhabets,
	gdawar, saugatm, vmireyno, zhangweining, Jason Wang

This patch introduces a vDPA transport for virtio. This is used to
use kernel virtio driver to drive the vDPA device that is capable
of populating virtqueue directly.

A new virtio-vdpa driver will be registered to the vDPA bus, when a
new virtio-vdpa device is probed, it will register the device with
vdpa based config ops. This means it is a software transport between
vDPA driver and vDPA device. The transport was implemented through
bus_ops of vDPA parent.

Signed-off-by: Jason Wang <jasowang@redhat.com>
---
 drivers/virtio/Kconfig       |  13 ++
 drivers/virtio/Makefile      |   1 +
 drivers/virtio/virtio_vdpa.c | 396 +++++++++++++++++++++++++++++++++++
 3 files changed, 410 insertions(+)
 create mode 100644 drivers/virtio/virtio_vdpa.c

diff --git a/drivers/virtio/Kconfig b/drivers/virtio/Kconfig
index 9c4fdb64d9ac..99e424570644 100644
--- a/drivers/virtio/Kconfig
+++ b/drivers/virtio/Kconfig
@@ -43,6 +43,19 @@ config VIRTIO_PCI_LEGACY
 
 	  If unsure, say Y.
 
+config VIRTIO_VDPA
+	tristate "vDPA driver for virtio devices"
+	select VDPA
+	select VIRTIO
+	help
+	  This driver provides support for virtio based paravirtual
+	  device driver over vDPA bus. For this to be useful, you need
+	  an appropriate vDPA device implementation that operates on a
+	  physical device to allow the datapath of virtio to be
+	  offloaded to hardware.
+
+	  If unsure, say M.
+
 config VIRTIO_PMEM
 	tristate "Support for virtio pmem driver"
 	depends on VIRTIO
diff --git a/drivers/virtio/Makefile b/drivers/virtio/Makefile
index fdf5eacd0d0a..3407ac03fe60 100644
--- a/drivers/virtio/Makefile
+++ b/drivers/virtio/Makefile
@@ -6,4 +6,5 @@ virtio_pci-y := virtio_pci_modern.o virtio_pci_common.o
 virtio_pci-$(CONFIG_VIRTIO_PCI_LEGACY) += virtio_pci_legacy.o
 obj-$(CONFIG_VIRTIO_BALLOON) += virtio_balloon.o
 obj-$(CONFIG_VIRTIO_INPUT) += virtio_input.o
+obj-$(CONFIG_VIRTIO_VDPA) += virtio_vdpa.o
 obj-$(CONFIG_VDPA) += vdpa/
diff --git a/drivers/virtio/virtio_vdpa.c b/drivers/virtio/virtio_vdpa.c
new file mode 100644
index 000000000000..c30eb55030be
--- /dev/null
+++ b/drivers/virtio/virtio_vdpa.c
@@ -0,0 +1,396 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * VIRTIO based driver for vDPA device
+ *
+ * Copyright (c) 2020, Red Hat. All rights reserved.
+ *     Author: Jason Wang <jasowang@redhat.com>
+ *
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/uuid.h>
+#include <linux/virtio.h>
+#include <linux/vdpa.h>
+#include <linux/virtio_config.h>
+#include <linux/virtio_ring.h>
+
+#define MOD_VERSION  "0.1"
+#define MOD_AUTHOR   "Jason Wang <jasowang@redhat.com>"
+#define MOD_DESC     "vDPA bus driver for virtio devices"
+#define MOD_LICENSE  "GPL v2"
+
+struct virtio_vdpa_device {
+	struct virtio_device vdev;
+	struct vdpa_device *vdpa;
+	u64 features;
+
+	/* The lock to protect virtqueue list */
+	spinlock_t lock;
+	/* List of virtio_vdpa_vq_info */
+	struct list_head virtqueues;
+};
+
+struct virtio_vdpa_vq_info {
+	/* the actual virtqueue */
+	struct virtqueue *vq;
+
+	/* the list node for the virtqueues list */
+	struct list_head node;
+};
+
+static inline struct virtio_vdpa_device *
+to_virtio_vdpa_device(struct virtio_device *dev)
+{
+	return container_of(dev, struct virtio_vdpa_device, vdev);
+}
+
+static struct vdpa_device *vd_get_vdpa(struct virtio_device *vdev)
+{
+	return to_virtio_vdpa_device(vdev)->vdpa;
+}
+
+static void virtio_vdpa_get(struct virtio_device *vdev, unsigned offset,
+			    void *buf, unsigned len)
+{
+	struct vdpa_device *vdpa = vd_get_vdpa(vdev);
+	const struct vdpa_config_ops *ops = vdpa->config;
+
+	ops->get_config(vdpa, offset, buf, len);
+}
+
+static void virtio_vdpa_set(struct virtio_device *vdev, unsigned offset,
+			    const void *buf, unsigned len)
+{
+	struct vdpa_device *vdpa = vd_get_vdpa(vdev);
+	const struct vdpa_config_ops *ops = vdpa->config;
+
+	ops->set_config(vdpa, offset, buf, len);
+}
+
+static u32 virtio_vdpa_generation(struct virtio_device *vdev)
+{
+	struct vdpa_device *vdpa = vd_get_vdpa(vdev);
+	const struct vdpa_config_ops *ops = vdpa->config;
+
+	if (ops->get_generation)
+		return ops->get_generation(vdpa);
+
+	return 0;
+}
+
+static u8 virtio_vdpa_get_status(struct virtio_device *vdev)
+{
+	struct vdpa_device *vdpa = vd_get_vdpa(vdev);
+	const struct vdpa_config_ops *ops = vdpa->config;
+
+	return ops->get_status(vdpa);
+}
+
+static void virtio_vdpa_set_status(struct virtio_device *vdev, u8 status)
+{
+	struct vdpa_device *vdpa = vd_get_vdpa(vdev);
+	const struct vdpa_config_ops *ops = vdpa->config;
+
+	return ops->set_status(vdpa, status);
+}
+
+static void virtio_vdpa_reset(struct virtio_device *vdev)
+{
+	struct vdpa_device *vdpa = vd_get_vdpa(vdev);
+	const struct vdpa_config_ops *ops = vdpa->config;
+
+	return ops->set_status(vdpa, 0);
+}
+
+static bool virtio_vdpa_notify(struct virtqueue *vq)
+{
+	struct vdpa_device *vdpa = vd_get_vdpa(vq->vdev);
+	const struct vdpa_config_ops *ops = vdpa->config;
+
+	ops->kick_vq(vdpa, vq->index);
+
+	return true;
+}
+
+static irqreturn_t virtio_vdpa_config_cb(void *private)
+{
+	struct virtio_vdpa_device *vd_dev = private;
+
+	virtio_config_changed(&vd_dev->vdev);
+
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t virtio_vdpa_virtqueue_cb(void *private)
+{
+	struct virtio_vdpa_vq_info *info = private;
+
+	return vring_interrupt(0, info->vq);
+}
+
+static struct virtqueue *
+virtio_vdpa_setup_vq(struct virtio_device *vdev, unsigned int index,
+		     void (*callback)(struct virtqueue *vq),
+		     const char *name, bool ctx)
+{
+	struct virtio_vdpa_device *vd_dev = to_virtio_vdpa_device(vdev);
+	struct vdpa_device *vdpa = vd_get_vdpa(vdev);
+	const struct vdpa_config_ops *ops = vdpa->config;
+	struct virtio_vdpa_vq_info *info;
+	struct vdpa_callback cb;
+	struct virtqueue *vq;
+	u64 desc_addr, driver_addr, device_addr;
+	unsigned long flags;
+	u32 align, num;
+	int err;
+
+	if (!name)
+		return NULL;
+
+	/* Queue shouldn't already be set up. */
+	if (ops->get_vq_ready(vdpa, index))
+		return ERR_PTR(-ENOENT);
+
+	/* Allocate and fill out our active queue description */
+	info = kmalloc(sizeof(*info), GFP_KERNEL);
+	if (!info)
+		return ERR_PTR(-ENOMEM);
+
+	num = ops->get_vq_num_max(vdpa);
+	if (num == 0) {
+		err = -ENOENT;
+		goto error_new_virtqueue;
+	}
+
+	/* Create the vring */
+	align = ops->get_vq_align(vdpa);
+	vq = vring_create_virtqueue(index, num, align, vdev,
+				    true, true, ctx,
+				    virtio_vdpa_notify, callback, name);
+	if (!vq) {
+		err = -ENOMEM;
+		goto error_new_virtqueue;
+	}
+
+	/* Setup virtqueue callback */
+	cb.callback = virtio_vdpa_virtqueue_cb;
+	cb.private = info;
+	ops->set_vq_cb(vdpa, index, &cb);
+	ops->set_vq_num(vdpa, index, virtqueue_get_vring_size(vq));
+
+	desc_addr = virtqueue_get_desc_addr(vq);
+	driver_addr = virtqueue_get_avail_addr(vq);
+	device_addr = virtqueue_get_used_addr(vq);
+
+	if (ops->set_vq_address(vdpa, index,
+				desc_addr, driver_addr,
+				device_addr)) {
+		err = -EINVAL;
+		goto err_vq;
+	}
+
+	ops->set_vq_ready(vdpa, index, 1);
+
+	vq->priv = info;
+	info->vq = vq;
+
+	spin_lock_irqsave(&vd_dev->lock, flags);
+	list_add(&info->node, &vd_dev->virtqueues);
+	spin_unlock_irqrestore(&vd_dev->lock, flags);
+
+	return vq;
+
+err_vq:
+	vring_del_virtqueue(vq);
+error_new_virtqueue:
+	ops->set_vq_ready(vdpa, index, 0);
+	/* VDPA driver should make sure vq is stopeed here */
+	WARN_ON(ops->get_vq_ready(vdpa, index));
+	kfree(info);
+	return ERR_PTR(err);
+}
+
+static void virtio_vdpa_del_vq(struct virtqueue *vq)
+{
+	struct virtio_vdpa_device *vd_dev = to_virtio_vdpa_device(vq->vdev);
+	struct vdpa_device *vdpa = vd_dev->vdpa;
+	const struct vdpa_config_ops *ops = vdpa->config;
+	struct virtio_vdpa_vq_info *info = vq->priv;
+	unsigned int index = vq->index;
+	unsigned long flags;
+
+	spin_lock_irqsave(&vd_dev->lock, flags);
+	list_del(&info->node);
+	spin_unlock_irqrestore(&vd_dev->lock, flags);
+
+	/* Select and deactivate the queue */
+	ops->set_vq_ready(vdpa, index, 0);
+	WARN_ON(ops->get_vq_ready(vdpa, index));
+
+	vring_del_virtqueue(vq);
+
+	kfree(info);
+}
+
+static void virtio_vdpa_del_vqs(struct virtio_device *vdev)
+{
+	struct virtqueue *vq, *n;
+
+	list_for_each_entry_safe(vq, n, &vdev->vqs, list)
+		virtio_vdpa_del_vq(vq);
+}
+
+static int virtio_vdpa_find_vqs(struct virtio_device *vdev, unsigned nvqs,
+				struct virtqueue *vqs[],
+				vq_callback_t *callbacks[],
+				const char * const names[],
+				const bool *ctx,
+				struct irq_affinity *desc)
+{
+	struct virtio_vdpa_device *vd_dev = to_virtio_vdpa_device(vdev);
+	struct vdpa_device *vdpa = vd_get_vdpa(vdev);
+	const struct vdpa_config_ops *ops = vdpa->config;
+	struct vdpa_callback cb;
+	int i, err, queue_idx = 0;
+
+	for (i = 0; i < nvqs; ++i) {
+		if (!names[i]) {
+			vqs[i] = NULL;
+			continue;
+		}
+
+		vqs[i] = virtio_vdpa_setup_vq(vdev, queue_idx++,
+					      callbacks[i], names[i], ctx ?
+					      ctx[i] : false);
+		if (IS_ERR(vqs[i])) {
+			err = PTR_ERR(vqs[i]);
+			goto err_setup_vq;
+		}
+	}
+
+	cb.callback = virtio_vdpa_config_cb;
+	cb.private = vd_dev;
+	ops->set_config_cb(vdpa, &cb);
+
+	return 0;
+
+err_setup_vq:
+	virtio_vdpa_del_vqs(vdev);
+	return err;
+}
+
+static u64 virtio_vdpa_get_features(struct virtio_device *vdev)
+{
+	struct vdpa_device *vdpa = vd_get_vdpa(vdev);
+	const struct vdpa_config_ops *ops = vdpa->config;
+
+	return ops->get_features(vdpa);
+}
+
+static int virtio_vdpa_finalize_features(struct virtio_device *vdev)
+{
+	struct vdpa_device *vdpa = vd_get_vdpa(vdev);
+	const struct vdpa_config_ops *ops = vdpa->config;
+
+	/* Give virtio_ring a chance to accept features. */
+	vring_transport_features(vdev);
+
+	return ops->set_features(vdpa, vdev->features);
+}
+
+static const char *virtio_vdpa_bus_name(struct virtio_device *vdev)
+{
+	struct virtio_vdpa_device *vd_dev = to_virtio_vdpa_device(vdev);
+	struct vdpa_device *vdpa = vd_dev->vdpa;
+
+	return dev_name(&vdpa->dev);
+}
+
+static const struct virtio_config_ops virtio_vdpa_config_ops = {
+	.get		= virtio_vdpa_get,
+	.set		= virtio_vdpa_set,
+	.generation	= virtio_vdpa_generation,
+	.get_status	= virtio_vdpa_get_status,
+	.set_status	= virtio_vdpa_set_status,
+	.reset		= virtio_vdpa_reset,
+	.find_vqs	= virtio_vdpa_find_vqs,
+	.del_vqs	= virtio_vdpa_del_vqs,
+	.get_features	= virtio_vdpa_get_features,
+	.finalize_features = virtio_vdpa_finalize_features,
+	.bus_name	= virtio_vdpa_bus_name,
+};
+
+static void virtio_vdpa_release_dev(struct device *_d)
+{
+	struct virtio_device *vdev =
+	       container_of(_d, struct virtio_device, dev);
+	struct virtio_vdpa_device *vd_dev =
+	       container_of(vdev, struct virtio_vdpa_device, vdev);
+
+	kfree(vd_dev);
+}
+
+static int virtio_vdpa_probe(struct vdpa_device *vdpa)
+{
+	const struct vdpa_config_ops *ops = vdpa->config;
+	struct virtio_vdpa_device *vd_dev, *reg_dev = NULL;
+	int ret = -EINVAL;
+
+	vd_dev = kzalloc(sizeof(*vd_dev), GFP_KERNEL);
+	if (!vd_dev)
+		return -ENOMEM;
+
+	vd_dev->vdev.dev.parent = vdpa_get_dma_dev(vdpa);
+	vd_dev->vdev.dev.release = virtio_vdpa_release_dev;
+	vd_dev->vdev.config = &virtio_vdpa_config_ops;
+	vd_dev->vdpa = vdpa;
+	INIT_LIST_HEAD(&vd_dev->virtqueues);
+	spin_lock_init(&vd_dev->lock);
+
+	vd_dev->vdev.id.device = ops->get_device_id(vdpa);
+	if (vd_dev->vdev.id.device == 0)
+		goto err;
+
+	vd_dev->vdev.id.vendor = ops->get_vendor_id(vdpa);
+	ret = register_virtio_device(&vd_dev->vdev);
+	reg_dev = vd_dev;
+	if (ret)
+		goto err;
+
+	vdpa_set_drvdata(vdpa, vd_dev);
+
+	return 0;
+
+err:
+	if (reg_dev)
+		put_device(&vd_dev->vdev.dev);
+	else
+		kfree(vd_dev);
+	return ret;
+}
+
+static void virtio_vdpa_remove(struct vdpa_device *vdpa)
+{
+	struct virtio_vdpa_device *vd_dev = vdpa_get_drvdata(vdpa);
+
+	unregister_virtio_device(&vd_dev->vdev);
+}
+
+static struct vdpa_driver virtio_vdpa_driver = {
+	.driver = {
+		.name	= "virtio_vdpa",
+	},
+	.probe	= virtio_vdpa_probe,
+	.remove = virtio_vdpa_remove,
+};
+
+module_vdpa_driver(virtio_vdpa_driver);
+
+MODULE_VERSION(MOD_VERSION);
+MODULE_LICENSE(MOD_LICENSE);
+MODULE_AUTHOR(MOD_AUTHOR);
+MODULE_DESCRIPTION(MOD_DESC);
-- 
2.20.1


^ permalink raw reply	[flat|nested] 38+ messages in thread

* [PATCH V9 7/9] vhost: introduce vDPA-based backend
  2020-03-26 14:01 [PATCH V9 0/9] vDPA support Jason Wang
                   ` (5 preceding siblings ...)
  2020-03-26 14:01 ` [PATCH V9 6/9] virtio: introduce a vDPA based transport Jason Wang
@ 2020-03-26 14:01 ` Jason Wang
  2020-03-26 14:01 ` [PATCH V9 8/9] vdpasim: vDPA device simulator Jason Wang
                   ` (2 subsequent siblings)
  9 siblings, 0 replies; 38+ messages in thread
From: Jason Wang @ 2020-03-26 14:01 UTC (permalink / raw)
  To: mst, linux-kernel, kvm, virtualization, netdev
  Cc: jgg, maxime.coquelin, cunming.liang, zhihong.wang, rob.miller,
	xiao.w.wang, lingshan.zhu, eperezma, lulu, parav, kevin.tian,
	stefanha, rdunlap, hch, aadam, jiri, shahafs, hanand, mhabets,
	gdawar, saugatm, vmireyno, zhangweining, Tiwei Bie, Jason Wang

From: Tiwei Bie <tiwei.bie@intel.com>

This patch introduces a vDPA-based vhost backend. This backend is
built on top of the same interface defined in virtio-vDPA and provides
a generic vhost interface for userspace to accelerate the virtio
devices in guest.

This backend is implemented as a vDPA device driver on top of the same
ops used in virtio-vDPA. It will create char device entry named
vhost-vdpa-$index for userspace to use. Userspace can use vhost ioctls
on top of this char device to setup the backend.

Vhost ioctls are extended to make it type agnostic and behave like a
virtio device, this help to eliminate type specific API like what
vhost_net/scsi/vsock did:

- VHOST_VDPA_GET_DEVICE_ID: get the virtio device ID which is defined
  by virtio specification to differ from different type of devices
- VHOST_VDPA_GET_VRING_NUM: get the maximum size of virtqueue
  supported by the vDPA device
- VHSOT_VDPA_SET/GET_STATUS: set and get virtio status of vDPA device
- VHOST_VDPA_SET/GET_CONFIG: access virtio config space
- VHOST_VDPA_SET_VRING_ENABLE: enable a specific virtqueue

For memory mapping, IOTLB API is mandated for vhost-vDPA which means
userspace drivers are required to use
VHOST_IOTLB_UPDATE/VHOST_IOTLB_INVALIDATE to add or remove mapping for
a specific userspace memory region.

The vhost-vDPA API is designed to be type agnostic, but it allows net
device only in current stage. Due to the lacking of control virtqueue
support, some features were filter out by vhost-vdpa.

We will enable more features and devices in the near future.

Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
---
 drivers/vhost/Kconfig            |  11 +
 drivers/vhost/Makefile           |   3 +
 drivers/vhost/vdpa.c             | 883 +++++++++++++++++++++++++++++++
 include/uapi/linux/vhost.h       |  24 +
 include/uapi/linux/vhost_types.h |   8 +
 5 files changed, 929 insertions(+)
 create mode 100644 drivers/vhost/vdpa.c

diff --git a/drivers/vhost/Kconfig b/drivers/vhost/Kconfig
index b03872886901..2a4efe39d79b 100644
--- a/drivers/vhost/Kconfig
+++ b/drivers/vhost/Kconfig
@@ -52,6 +52,17 @@ config VHOST_VSOCK
 	To compile this driver as a module, choose M here: the module will be called
 	vhost_vsock.
 
+config VHOST_VDPA
+	tristate "Vhost driver for vDPA-based backend"
+	depends on EVENTFD
+	select VDPA
+	help
+	  This kernel module can be loaded in host kernel to accelerate
+	  guest virtio devices with the vDPA-based backends.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called vhost_vdpa.
+
 config VHOST_CROSS_ENDIAN_LEGACY
 	bool "Cross-endian support for vhost"
 	default n
diff --git a/drivers/vhost/Makefile b/drivers/vhost/Makefile
index fb831002bcf0..f3e1897cce85 100644
--- a/drivers/vhost/Makefile
+++ b/drivers/vhost/Makefile
@@ -10,6 +10,9 @@ vhost_vsock-y := vsock.o
 
 obj-$(CONFIG_VHOST_RING) += vringh.o
 
+obj-$(CONFIG_VHOST_VDPA) += vhost_vdpa.o
+vhost_vdpa-y := vdpa.o
+
 obj-$(CONFIG_VHOST)	+= vhost.o
 
 obj-$(CONFIG_VHOST_IOTLB) += vhost_iotlb.o
diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
new file mode 100644
index 000000000000..421f02a8530a
--- /dev/null
+++ b/drivers/vhost/vdpa.c
@@ -0,0 +1,883 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2018-2020 Intel Corporation.
+ * Copyright (C) 2020 Red Hat, Inc.
+ *
+ * Author: Tiwei Bie <tiwei.bie@intel.com>
+ *         Jason Wang <jasowang@redhat.com>
+ *
+ * Thanks Michael S. Tsirkin for the valuable comments and
+ * suggestions.  And thanks to Cunming Liang and Zhihong Wang for all
+ * their supports.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/cdev.h>
+#include <linux/device.h>
+#include <linux/iommu.h>
+#include <linux/uuid.h>
+#include <linux/vdpa.h>
+#include <linux/nospec.h>
+#include <linux/vhost.h>
+#include <linux/virtio_net.h>
+
+#include "vhost.h"
+
+enum {
+	VHOST_VDPA_FEATURES =
+		(1ULL << VIRTIO_F_NOTIFY_ON_EMPTY) |
+		(1ULL << VIRTIO_F_ANY_LAYOUT) |
+		(1ULL << VIRTIO_F_VERSION_1) |
+		(1ULL << VIRTIO_F_IOMMU_PLATFORM) |
+		(1ULL << VIRTIO_F_RING_PACKED) |
+		(1ULL << VIRTIO_F_ORDER_PLATFORM) |
+		(1ULL << VIRTIO_RING_F_INDIRECT_DESC) |
+		(1ULL << VIRTIO_RING_F_EVENT_IDX),
+
+	VHOST_VDPA_NET_FEATURES = VHOST_VDPA_FEATURES |
+		(1ULL << VIRTIO_NET_F_CSUM) |
+		(1ULL << VIRTIO_NET_F_GUEST_CSUM) |
+		(1ULL << VIRTIO_NET_F_MTU) |
+		(1ULL << VIRTIO_NET_F_MAC) |
+		(1ULL << VIRTIO_NET_F_GUEST_TSO4) |
+		(1ULL << VIRTIO_NET_F_GUEST_TSO6) |
+		(1ULL << VIRTIO_NET_F_GUEST_ECN) |
+		(1ULL << VIRTIO_NET_F_GUEST_UFO) |
+		(1ULL << VIRTIO_NET_F_HOST_TSO4) |
+		(1ULL << VIRTIO_NET_F_HOST_TSO6) |
+		(1ULL << VIRTIO_NET_F_HOST_ECN) |
+		(1ULL << VIRTIO_NET_F_HOST_UFO) |
+		(1ULL << VIRTIO_NET_F_MRG_RXBUF) |
+		(1ULL << VIRTIO_NET_F_STATUS) |
+		(1ULL << VIRTIO_NET_F_SPEED_DUPLEX),
+};
+
+/* Currently, only network backend w/o multiqueue is supported. */
+#define VHOST_VDPA_VQ_MAX	2
+
+#define VHOST_VDPA_DEV_MAX (1U << MINORBITS)
+
+struct vhost_vdpa {
+	struct vhost_dev vdev;
+	struct iommu_domain *domain;
+	struct vhost_virtqueue *vqs;
+	struct completion completion;
+	struct vdpa_device *vdpa;
+	struct device dev;
+	struct cdev cdev;
+	atomic_t opened;
+	int nvqs;
+	int virtio_id;
+	int minor;
+};
+
+static DEFINE_IDA(vhost_vdpa_ida);
+
+static dev_t vhost_vdpa_major;
+
+static const u64 vhost_vdpa_features[] = {
+	[VIRTIO_ID_NET] = VHOST_VDPA_NET_FEATURES,
+};
+
+static void handle_vq_kick(struct vhost_work *work)
+{
+	struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
+						  poll.work);
+	struct vhost_vdpa *v = container_of(vq->dev, struct vhost_vdpa, vdev);
+	const struct vdpa_config_ops *ops = v->vdpa->config;
+
+	ops->kick_vq(v->vdpa, vq - v->vqs);
+}
+
+static irqreturn_t vhost_vdpa_virtqueue_cb(void *private)
+{
+	struct vhost_virtqueue *vq = private;
+	struct eventfd_ctx *call_ctx = vq->call_ctx;
+
+	if (call_ctx)
+		eventfd_signal(call_ctx, 1);
+
+	return IRQ_HANDLED;
+}
+
+static void vhost_vdpa_reset(struct vhost_vdpa *v)
+{
+	struct vdpa_device *vdpa = v->vdpa;
+	const struct vdpa_config_ops *ops = vdpa->config;
+
+	ops->set_status(vdpa, 0);
+}
+
+static long vhost_vdpa_get_device_id(struct vhost_vdpa *v, u8 __user *argp)
+{
+	struct vdpa_device *vdpa = v->vdpa;
+	const struct vdpa_config_ops *ops = vdpa->config;
+	u32 device_id;
+
+	device_id = ops->get_device_id(vdpa);
+
+	if (copy_to_user(argp, &device_id, sizeof(device_id)))
+		return -EFAULT;
+
+	return 0;
+}
+
+static long vhost_vdpa_get_status(struct vhost_vdpa *v, u8 __user *statusp)
+{
+	struct vdpa_device *vdpa = v->vdpa;
+	const struct vdpa_config_ops *ops = vdpa->config;
+	u8 status;
+
+	status = ops->get_status(vdpa);
+
+	if (copy_to_user(statusp, &status, sizeof(status)))
+		return -EFAULT;
+
+	return 0;
+}
+
+static long vhost_vdpa_set_status(struct vhost_vdpa *v, u8 __user *statusp)
+{
+	struct vdpa_device *vdpa = v->vdpa;
+	const struct vdpa_config_ops *ops = vdpa->config;
+	u8 status;
+
+	if (copy_from_user(&status, statusp, sizeof(status)))
+		return -EFAULT;
+
+	/*
+	 * Userspace shouldn't remove status bits unless reset the
+	 * status to 0.
+	 */
+	if (status != 0 && (ops->get_status(vdpa) & ~status) != 0)
+		return -EINVAL;
+
+	ops->set_status(vdpa, status);
+
+	return 0;
+}
+
+static int vhost_vdpa_config_validate(struct vhost_vdpa *v,
+				      struct vhost_vdpa_config *c)
+{
+	long size = 0;
+
+	switch (v->virtio_id) {
+	case VIRTIO_ID_NET:
+		size = sizeof(struct virtio_net_config);
+		break;
+	}
+
+	if (c->len == 0)
+		return -EINVAL;
+
+	if (c->len > size - c->off)
+		return -E2BIG;
+
+	return 0;
+}
+
+static long vhost_vdpa_get_config(struct vhost_vdpa *v,
+				  struct vhost_vdpa_config __user *c)
+{
+	struct vdpa_device *vdpa = v->vdpa;
+	const struct vdpa_config_ops *ops = vdpa->config;
+	struct vhost_vdpa_config config;
+	unsigned long size = offsetof(struct vhost_vdpa_config, buf);
+	u8 *buf;
+
+	if (copy_from_user(&config, c, size))
+		return -EFAULT;
+	if (vhost_vdpa_config_validate(v, &config))
+		return -EINVAL;
+	buf = kvzalloc(config.len, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	ops->get_config(vdpa, config.off, buf, config.len);
+
+	if (copy_to_user(c->buf, buf, config.len)) {
+		kvfree(buf);
+		return -EFAULT;
+	}
+
+	kvfree(buf);
+	return 0;
+}
+
+static long vhost_vdpa_set_config(struct vhost_vdpa *v,
+				  struct vhost_vdpa_config __user *c)
+{
+	struct vdpa_device *vdpa = v->vdpa;
+	const struct vdpa_config_ops *ops = vdpa->config;
+	struct vhost_vdpa_config config;
+	unsigned long size = offsetof(struct vhost_vdpa_config, buf);
+	u8 *buf;
+
+	if (copy_from_user(&config, c, size))
+		return -EFAULT;
+	if (vhost_vdpa_config_validate(v, &config))
+		return -EINVAL;
+	buf = kvzalloc(config.len, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	if (copy_from_user(buf, c->buf, config.len)) {
+		kvfree(buf);
+		return -EFAULT;
+	}
+
+	ops->set_config(vdpa, config.off, buf, config.len);
+
+	kvfree(buf);
+	return 0;
+}
+
+static long vhost_vdpa_get_features(struct vhost_vdpa *v, u64 __user *featurep)
+{
+	struct vdpa_device *vdpa = v->vdpa;
+	const struct vdpa_config_ops *ops = vdpa->config;
+	u64 features;
+
+	features = ops->get_features(vdpa);
+	features &= vhost_vdpa_features[v->virtio_id];
+
+	if (copy_to_user(featurep, &features, sizeof(features)))
+		return -EFAULT;
+
+	return 0;
+}
+
+static long vhost_vdpa_set_features(struct vhost_vdpa *v, u64 __user *featurep)
+{
+	struct vdpa_device *vdpa = v->vdpa;
+	const struct vdpa_config_ops *ops = vdpa->config;
+	u64 features;
+
+	/*
+	 * It's not allowed to change the features after they have
+	 * been negotiated.
+	 */
+	if (ops->get_status(vdpa) & VIRTIO_CONFIG_S_FEATURES_OK)
+		return -EBUSY;
+
+	if (copy_from_user(&features, featurep, sizeof(features)))
+		return -EFAULT;
+
+	if (features & ~vhost_vdpa_features[v->virtio_id])
+		return -EINVAL;
+
+	if (ops->set_features(vdpa, features))
+		return -EINVAL;
+
+	return 0;
+}
+
+static long vhost_vdpa_get_vring_num(struct vhost_vdpa *v, u16 __user *argp)
+{
+	struct vdpa_device *vdpa = v->vdpa;
+	const struct vdpa_config_ops *ops = vdpa->config;
+	u16 num;
+
+	num = ops->get_vq_num_max(vdpa);
+
+	if (copy_to_user(argp, &num, sizeof(num)))
+		return -EFAULT;
+
+	return 0;
+}
+
+static long vhost_vdpa_vring_ioctl(struct vhost_vdpa *v, unsigned int cmd,
+				   void __user *argp)
+{
+	struct vdpa_device *vdpa = v->vdpa;
+	const struct vdpa_config_ops *ops = vdpa->config;
+	struct vdpa_callback cb;
+	struct vhost_virtqueue *vq;
+	struct vhost_vring_state s;
+	u8 status;
+	u32 idx;
+	long r;
+
+	r = get_user(idx, (u32 __user *)argp);
+	if (r < 0)
+		return r;
+
+	if (idx >= v->nvqs)
+		return -ENOBUFS;
+
+	idx = array_index_nospec(idx, v->nvqs);
+	vq = &v->vqs[idx];
+
+	status = ops->get_status(vdpa);
+
+	if (cmd == VHOST_VDPA_SET_VRING_ENABLE) {
+		if (copy_from_user(&s, argp, sizeof(s)))
+			return -EFAULT;
+		ops->set_vq_ready(vdpa, idx, s.num);
+		return 0;
+	}
+
+	if (cmd == VHOST_GET_VRING_BASE)
+		vq->last_avail_idx = ops->get_vq_state(v->vdpa, idx);
+
+	r = vhost_vring_ioctl(&v->vdev, cmd, argp);
+	if (r)
+		return r;
+
+	switch (cmd) {
+	case VHOST_SET_VRING_ADDR:
+		if (ops->set_vq_address(vdpa, idx,
+					(u64)(uintptr_t)vq->desc,
+					(u64)(uintptr_t)vq->avail,
+					(u64)(uintptr_t)vq->used))
+			r = -EINVAL;
+		break;
+
+	case VHOST_SET_VRING_BASE:
+		if (ops->set_vq_state(vdpa, idx, vq->last_avail_idx))
+			r = -EINVAL;
+		break;
+
+	case VHOST_SET_VRING_CALL:
+		if (vq->call_ctx) {
+			cb.callback = vhost_vdpa_virtqueue_cb;
+			cb.private = vq;
+		} else {
+			cb.callback = NULL;
+			cb.private = NULL;
+		}
+		ops->set_vq_cb(vdpa, idx, &cb);
+		break;
+
+	case VHOST_SET_VRING_NUM:
+		ops->set_vq_num(vdpa, idx, vq->num);
+		break;
+	}
+
+	return r;
+}
+
+static long vhost_vdpa_unlocked_ioctl(struct file *filep,
+				      unsigned int cmd, unsigned long arg)
+{
+	struct vhost_vdpa *v = filep->private_data;
+	struct vhost_dev *d = &v->vdev;
+	void __user *argp = (void __user *)arg;
+	long r;
+
+	mutex_lock(&d->mutex);
+
+	switch (cmd) {
+	case VHOST_VDPA_GET_DEVICE_ID:
+		r = vhost_vdpa_get_device_id(v, argp);
+		break;
+	case VHOST_VDPA_GET_STATUS:
+		r = vhost_vdpa_get_status(v, argp);
+		break;
+	case VHOST_VDPA_SET_STATUS:
+		r = vhost_vdpa_set_status(v, argp);
+		break;
+	case VHOST_VDPA_GET_CONFIG:
+		r = vhost_vdpa_get_config(v, argp);
+		break;
+	case VHOST_VDPA_SET_CONFIG:
+		r = vhost_vdpa_set_config(v, argp);
+		break;
+	case VHOST_GET_FEATURES:
+		r = vhost_vdpa_get_features(v, argp);
+		break;
+	case VHOST_SET_FEATURES:
+		r = vhost_vdpa_set_features(v, argp);
+		break;
+	case VHOST_VDPA_GET_VRING_NUM:
+		r = vhost_vdpa_get_vring_num(v, argp);
+		break;
+	case VHOST_SET_LOG_BASE:
+	case VHOST_SET_LOG_FD:
+		r = -ENOIOCTLCMD;
+		break;
+	default:
+		r = vhost_dev_ioctl(&v->vdev, cmd, argp);
+		if (r == -ENOIOCTLCMD)
+			r = vhost_vdpa_vring_ioctl(v, cmd, argp);
+		break;
+	}
+
+	mutex_unlock(&d->mutex);
+	return r;
+}
+
+static void vhost_vdpa_iotlb_unmap(struct vhost_vdpa *v, u64 start, u64 last)
+{
+	struct vhost_dev *dev = &v->vdev;
+	struct vhost_iotlb *iotlb = dev->iotlb;
+	struct vhost_iotlb_map *map;
+	struct page *page;
+	unsigned long pfn, pinned;
+
+	while ((map = vhost_iotlb_itree_first(iotlb, start, last)) != NULL) {
+		pinned = map->size >> PAGE_SHIFT;
+		for (pfn = map->addr >> PAGE_SHIFT;
+		     pinned > 0; pfn++, pinned--) {
+			page = pfn_to_page(pfn);
+			if (map->perm & VHOST_ACCESS_WO)
+				set_page_dirty_lock(page);
+			unpin_user_page(page);
+		}
+		atomic64_sub(map->size >> PAGE_SHIFT, &dev->mm->pinned_vm);
+		vhost_iotlb_map_free(iotlb, map);
+	}
+}
+
+static void vhost_vdpa_iotlb_free(struct vhost_vdpa *v)
+{
+	struct vhost_dev *dev = &v->vdev;
+
+	vhost_vdpa_iotlb_unmap(v, 0ULL, 0ULL - 1);
+	kfree(dev->iotlb);
+	dev->iotlb = NULL;
+}
+
+static int perm_to_iommu_flags(u32 perm)
+{
+	int flags = 0;
+
+	switch (perm) {
+	case VHOST_ACCESS_WO:
+		flags |= IOMMU_WRITE;
+		break;
+	case VHOST_ACCESS_RO:
+		flags |= IOMMU_READ;
+		break;
+	case VHOST_ACCESS_RW:
+		flags |= (IOMMU_WRITE | IOMMU_READ);
+		break;
+	default:
+		WARN(1, "invalidate vhost IOTLB permission\n");
+		break;
+	}
+
+	return flags | IOMMU_CACHE;
+}
+
+static int vhost_vdpa_map(struct vhost_vdpa *v,
+			  u64 iova, u64 size, u64 pa, u32 perm)
+{
+	struct vhost_dev *dev = &v->vdev;
+	struct vdpa_device *vdpa = v->vdpa;
+	const struct vdpa_config_ops *ops = vdpa->config;
+	int r = 0;
+
+	r = vhost_iotlb_add_range(dev->iotlb, iova, iova + size - 1,
+				  pa, perm);
+	if (r)
+		return r;
+
+	if (ops->dma_map)
+		r = ops->dma_map(vdpa, iova, size, pa, perm);
+	else if (ops->set_map)
+		r = ops->set_map(vdpa, dev->iotlb);
+	else
+		r = iommu_map(v->domain, iova, pa, size,
+			      perm_to_iommu_flags(perm));
+
+	return r;
+}
+
+static void vhost_vdpa_unmap(struct vhost_vdpa *v, u64 iova, u64 size)
+{
+	struct vhost_dev *dev = &v->vdev;
+	struct vdpa_device *vdpa = v->vdpa;
+	const struct vdpa_config_ops *ops = vdpa->config;
+
+	vhost_vdpa_iotlb_unmap(v, iova, iova + size - 1);
+
+	if (ops->dma_map)
+		ops->dma_unmap(vdpa, iova, size);
+	else if (ops->set_map)
+		ops->set_map(vdpa, dev->iotlb);
+	else
+		iommu_unmap(v->domain, iova, size);
+}
+
+static int vhost_vdpa_process_iotlb_update(struct vhost_vdpa *v,
+					   struct vhost_iotlb_msg *msg)
+{
+	struct vhost_dev *dev = &v->vdev;
+	struct vhost_iotlb *iotlb = dev->iotlb;
+	struct page **page_list;
+	unsigned long list_size = PAGE_SIZE / sizeof(struct page *);
+	unsigned int gup_flags = FOLL_LONGTERM;
+	unsigned long npages, cur_base, map_pfn, last_pfn = 0;
+	unsigned long locked, lock_limit, pinned, i;
+	u64 iova = msg->iova;
+	int ret = 0;
+
+	if (vhost_iotlb_itree_first(iotlb, msg->iova,
+				    msg->iova + msg->size - 1))
+		return -EEXIST;
+
+	page_list = (struct page **) __get_free_page(GFP_KERNEL);
+	if (!page_list)
+		return -ENOMEM;
+
+	if (msg->perm & VHOST_ACCESS_WO)
+		gup_flags |= FOLL_WRITE;
+
+	npages = PAGE_ALIGN(msg->size + (iova & ~PAGE_MASK)) >> PAGE_SHIFT;
+	if (!npages)
+		return -EINVAL;
+
+	down_read(&dev->mm->mmap_sem);
+
+	locked = atomic64_add_return(npages, &dev->mm->pinned_vm);
+	lock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
+
+	if (locked > lock_limit) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	cur_base = msg->uaddr & PAGE_MASK;
+	iova &= PAGE_MASK;
+
+	while (npages) {
+		pinned = min_t(unsigned long, npages, list_size);
+		ret = pin_user_pages(cur_base, pinned,
+				     gup_flags, page_list, NULL);
+		if (ret != pinned)
+			goto out;
+
+		if (!last_pfn)
+			map_pfn = page_to_pfn(page_list[0]);
+
+		for (i = 0; i < ret; i++) {
+			unsigned long this_pfn = page_to_pfn(page_list[i]);
+			u64 csize;
+
+			if (last_pfn && (this_pfn != last_pfn + 1)) {
+				/* Pin a contiguous chunk of memory */
+				csize = (last_pfn - map_pfn + 1) << PAGE_SHIFT;
+				if (vhost_vdpa_map(v, iova, csize,
+						   map_pfn << PAGE_SHIFT,
+						   msg->perm))
+					goto out;
+				map_pfn = this_pfn;
+				iova += csize;
+			}
+
+			last_pfn = this_pfn;
+		}
+
+		cur_base += ret << PAGE_SHIFT;
+		npages -= ret;
+	}
+
+	/* Pin the rest chunk */
+	ret = vhost_vdpa_map(v, iova, (last_pfn - map_pfn + 1) << PAGE_SHIFT,
+			     map_pfn << PAGE_SHIFT, msg->perm);
+out:
+	if (ret) {
+		vhost_vdpa_unmap(v, msg->iova, msg->size);
+		atomic64_sub(npages, &dev->mm->pinned_vm);
+	}
+	up_read(&dev->mm->mmap_sem);
+	free_page((unsigned long)page_list);
+	return ret;
+}
+
+static int vhost_vdpa_process_iotlb_msg(struct vhost_dev *dev,
+					struct vhost_iotlb_msg *msg)
+{
+	struct vhost_vdpa *v = container_of(dev, struct vhost_vdpa, vdev);
+	int r = 0;
+
+	r = vhost_dev_check_owner(dev);
+	if (r)
+		return r;
+
+	switch (msg->type) {
+	case VHOST_IOTLB_UPDATE:
+		r = vhost_vdpa_process_iotlb_update(v, msg);
+		break;
+	case VHOST_IOTLB_INVALIDATE:
+		vhost_vdpa_unmap(v, msg->iova, msg->size);
+		break;
+	default:
+		r = -EINVAL;
+		break;
+	}
+
+	return r;
+}
+
+static ssize_t vhost_vdpa_chr_write_iter(struct kiocb *iocb,
+					 struct iov_iter *from)
+{
+	struct file *file = iocb->ki_filp;
+	struct vhost_vdpa *v = file->private_data;
+	struct vhost_dev *dev = &v->vdev;
+
+	return vhost_chr_write_iter(dev, from);
+}
+
+static int vhost_vdpa_alloc_domain(struct vhost_vdpa *v)
+{
+	struct vdpa_device *vdpa = v->vdpa;
+	const struct vdpa_config_ops *ops = vdpa->config;
+	struct device *dma_dev = vdpa_get_dma_dev(vdpa);
+	struct bus_type *bus;
+	int ret;
+
+	/* Device want to do DMA by itself */
+	if (ops->set_map || ops->dma_map)
+		return 0;
+
+	bus = dma_dev->bus;
+	if (!bus)
+		return -EFAULT;
+
+	if (!iommu_capable(bus, IOMMU_CAP_CACHE_COHERENCY))
+		return -ENOTSUPP;
+
+	v->domain = iommu_domain_alloc(bus);
+	if (!v->domain)
+		return -EIO;
+
+	ret = iommu_attach_device(v->domain, dma_dev);
+	if (ret)
+		goto err_attach;
+
+	return 0;
+
+err_attach:
+	iommu_domain_free(v->domain);
+	return ret;
+}
+
+static void vhost_vdpa_free_domain(struct vhost_vdpa *v)
+{
+	struct vdpa_device *vdpa = v->vdpa;
+	struct device *dma_dev = vdpa_get_dma_dev(vdpa);
+
+	if (v->domain) {
+		iommu_detach_device(v->domain, dma_dev);
+		iommu_domain_free(v->domain);
+	}
+
+	v->domain = NULL;
+}
+
+static int vhost_vdpa_open(struct inode *inode, struct file *filep)
+{
+	struct vhost_vdpa *v;
+	struct vhost_dev *dev;
+	struct vhost_virtqueue **vqs;
+	int nvqs, i, r, opened;
+
+	v = container_of(inode->i_cdev, struct vhost_vdpa, cdev);
+	if (!v)
+		return -ENODEV;
+
+	opened = atomic_cmpxchg(&v->opened, 0, 1);
+	if (opened)
+		return -EBUSY;
+
+	nvqs = v->nvqs;
+	vhost_vdpa_reset(v);
+
+	vqs = kmalloc_array(nvqs, sizeof(*vqs), GFP_KERNEL);
+	if (!vqs) {
+		r = -ENOMEM;
+		goto err;
+	}
+
+	dev = &v->vdev;
+	for (i = 0; i < nvqs; i++) {
+		vqs[i] = &v->vqs[i];
+		vqs[i]->handle_kick = handle_vq_kick;
+	}
+	vhost_dev_init(dev, vqs, nvqs, 0, 0, 0,
+		       vhost_vdpa_process_iotlb_msg);
+
+	dev->iotlb = vhost_iotlb_alloc(0, 0);
+	if (!dev->iotlb) {
+		r = -ENOMEM;
+		goto err_init_iotlb;
+	}
+
+	r = vhost_vdpa_alloc_domain(v);
+	if (r)
+		goto err_init_iotlb;
+
+	filep->private_data = v;
+
+	return 0;
+
+err_init_iotlb:
+	vhost_dev_cleanup(&v->vdev);
+err:
+	atomic_dec(&v->opened);
+	return r;
+}
+
+static int vhost_vdpa_release(struct inode *inode, struct file *filep)
+{
+	struct vhost_vdpa *v = filep->private_data;
+	struct vhost_dev *d = &v->vdev;
+
+	mutex_lock(&d->mutex);
+	filep->private_data = NULL;
+	vhost_vdpa_reset(v);
+	vhost_dev_stop(&v->vdev);
+	vhost_vdpa_iotlb_free(v);
+	vhost_vdpa_free_domain(v);
+	vhost_dev_cleanup(&v->vdev);
+	kfree(v->vdev.vqs);
+	mutex_unlock(&d->mutex);
+
+	atomic_dec(&v->opened);
+	complete(&v->completion);
+
+	return 0;
+}
+
+static const struct file_operations vhost_vdpa_fops = {
+	.owner		= THIS_MODULE,
+	.open		= vhost_vdpa_open,
+	.release	= vhost_vdpa_release,
+	.write_iter	= vhost_vdpa_chr_write_iter,
+	.unlocked_ioctl	= vhost_vdpa_unlocked_ioctl,
+	.compat_ioctl	= compat_ptr_ioctl,
+};
+
+static void vhost_vdpa_release_dev(struct device *device)
+{
+	struct vhost_vdpa *v =
+	       container_of(device, struct vhost_vdpa, dev);
+
+	ida_simple_remove(&vhost_vdpa_ida, v->minor);
+	kfree(v->vqs);
+	kfree(v);
+}
+
+static int vhost_vdpa_probe(struct vdpa_device *vdpa)
+{
+	const struct vdpa_config_ops *ops = vdpa->config;
+	struct vhost_vdpa *v;
+	int minor, nvqs = VHOST_VDPA_VQ_MAX;
+	int r;
+
+	/* Currently, we only accept the network devices. */
+	if (ops->get_device_id(vdpa) != VIRTIO_ID_NET)
+		return -ENOTSUPP;
+
+	v = kzalloc(sizeof(*v), GFP_KERNEL | __GFP_RETRY_MAYFAIL);
+	if (!v)
+		return -ENOMEM;
+
+	minor = ida_simple_get(&vhost_vdpa_ida, 0,
+			       VHOST_VDPA_DEV_MAX, GFP_KERNEL);
+	if (minor < 0) {
+		kfree(v);
+		return minor;
+	}
+
+	atomic_set(&v->opened, 0);
+	v->minor = minor;
+	v->vdpa = vdpa;
+	v->nvqs = nvqs;
+	v->virtio_id = ops->get_device_id(vdpa);
+
+	device_initialize(&v->dev);
+	v->dev.release = vhost_vdpa_release_dev;
+	v->dev.parent = &vdpa->dev;
+	v->dev.devt = MKDEV(MAJOR(vhost_vdpa_major), minor);
+	v->vqs = kmalloc_array(nvqs, sizeof(struct vhost_virtqueue),
+			       GFP_KERNEL);
+	if (!v->vqs) {
+		r = -ENOMEM;
+		goto err;
+	}
+
+	r = dev_set_name(&v->dev, "vhost-vdpa-%u", minor);
+	if (r)
+		goto err;
+
+	cdev_init(&v->cdev, &vhost_vdpa_fops);
+	v->cdev.owner = THIS_MODULE;
+
+	r = cdev_device_add(&v->cdev, &v->dev);
+	if (r)
+		goto err;
+
+	init_completion(&v->completion);
+	vdpa_set_drvdata(vdpa, v);
+
+	return 0;
+
+err:
+	put_device(&v->dev);
+	return r;
+}
+
+static void vhost_vdpa_remove(struct vdpa_device *vdpa)
+{
+	struct vhost_vdpa *v = vdpa_get_drvdata(vdpa);
+	int opened;
+
+	cdev_device_del(&v->cdev, &v->dev);
+
+	do {
+		opened = atomic_cmpxchg(&v->opened, 0, 1);
+		if (!opened)
+			break;
+		wait_for_completion(&v->completion);
+	} while (1);
+
+	put_device(&v->dev);
+}
+
+static struct vdpa_driver vhost_vdpa_driver = {
+	.driver = {
+		.name	= "vhost_vdpa",
+	},
+	.probe	= vhost_vdpa_probe,
+	.remove	= vhost_vdpa_remove,
+};
+
+static int __init vhost_vdpa_init(void)
+{
+	int r;
+
+	r = alloc_chrdev_region(&vhost_vdpa_major, 0, VHOST_VDPA_DEV_MAX,
+				"vhost-vdpa");
+	if (r)
+		goto err_alloc_chrdev;
+
+	r = vdpa_register_driver(&vhost_vdpa_driver);
+	if (r)
+		goto err_vdpa_register_driver;
+
+	return 0;
+
+err_vdpa_register_driver:
+	unregister_chrdev_region(vhost_vdpa_major, VHOST_VDPA_DEV_MAX);
+err_alloc_chrdev:
+	return r;
+}
+module_init(vhost_vdpa_init);
+
+static void __exit vhost_vdpa_exit(void)
+{
+	vdpa_unregister_driver(&vhost_vdpa_driver);
+	unregister_chrdev_region(vhost_vdpa_major, VHOST_VDPA_DEV_MAX);
+}
+module_exit(vhost_vdpa_exit);
+
+MODULE_VERSION("0.0.1");
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Intel Corporation");
+MODULE_DESCRIPTION("vDPA-based vhost backend for virtio");
diff --git a/include/uapi/linux/vhost.h b/include/uapi/linux/vhost.h
index 40d028eed645..9fe72e4b1373 100644
--- a/include/uapi/linux/vhost.h
+++ b/include/uapi/linux/vhost.h
@@ -116,4 +116,28 @@
 #define VHOST_VSOCK_SET_GUEST_CID	_IOW(VHOST_VIRTIO, 0x60, __u64)
 #define VHOST_VSOCK_SET_RUNNING		_IOW(VHOST_VIRTIO, 0x61, int)
 
+/* VHOST_VDPA specific defines */
+
+/* Get the device id. The device ids follow the same definition of
+ * the device id defined in virtio-spec.
+ */
+#define VHOST_VDPA_GET_DEVICE_ID	_IOR(VHOST_VIRTIO, 0x70, __u32)
+/* Get and set the status. The status bits follow the same definition
+ * of the device status defined in virtio-spec.
+ */
+#define VHOST_VDPA_GET_STATUS		_IOR(VHOST_VIRTIO, 0x71, __u8)
+#define VHOST_VDPA_SET_STATUS		_IOW(VHOST_VIRTIO, 0x72, __u8)
+/* Get and set the device config. The device config follows the same
+ * definition of the device config defined in virtio-spec.
+ */
+#define VHOST_VDPA_GET_CONFIG		_IOR(VHOST_VIRTIO, 0x73, \
+					     struct vhost_vdpa_config)
+#define VHOST_VDPA_SET_CONFIG		_IOW(VHOST_VIRTIO, 0x74, \
+					     struct vhost_vdpa_config)
+/* Enable/disable the ring. */
+#define VHOST_VDPA_SET_VRING_ENABLE	_IOW(VHOST_VIRTIO, 0x75, \
+					     struct vhost_vring_state)
+/* Get the max ring size. */
+#define VHOST_VDPA_GET_VRING_NUM	_IOR(VHOST_VIRTIO, 0x76, __u16)
+
 #endif
diff --git a/include/uapi/linux/vhost_types.h b/include/uapi/linux/vhost_types.h
index c907290ff065..669457ce5c48 100644
--- a/include/uapi/linux/vhost_types.h
+++ b/include/uapi/linux/vhost_types.h
@@ -119,6 +119,14 @@ struct vhost_scsi_target {
 	unsigned short reserved;
 };
 
+/* VHOST_VDPA specific definitions */
+
+struct vhost_vdpa_config {
+	__u32 off;
+	__u32 len;
+	__u8 buf[0];
+};
+
 /* Feature bits */
 /* Log all write descriptors. Can be changed while device is active. */
 #define VHOST_F_LOG_ALL 26
-- 
2.20.1


^ permalink raw reply	[flat|nested] 38+ messages in thread

* [PATCH V9 8/9] vdpasim: vDPA device simulator
  2020-03-26 14:01 [PATCH V9 0/9] vDPA support Jason Wang
                   ` (6 preceding siblings ...)
  2020-03-26 14:01 ` [PATCH V9 7/9] vhost: introduce vDPA-based backend Jason Wang
@ 2020-03-26 14:01 ` Jason Wang
  2020-03-26 14:01 ` [PATCH V9 9/9] virtio: Intel IFC VF driver for VDPA Jason Wang
  2020-03-29 11:07 ` [PATCH V9 0/9] vDPA support Michael S. Tsirkin
  9 siblings, 0 replies; 38+ messages in thread
From: Jason Wang @ 2020-03-26 14:01 UTC (permalink / raw)
  To: mst, linux-kernel, kvm, virtualization, netdev
  Cc: jgg, maxime.coquelin, cunming.liang, zhihong.wang, rob.miller,
	xiao.w.wang, lingshan.zhu, eperezma, lulu, parav, kevin.tian,
	stefanha, rdunlap, hch, aadam, jiri, shahafs, hanand, mhabets,
	gdawar, saugatm, vmireyno, zhangweining, Jason Wang

This patch implements a software vDPA networking device. The datapath
is implemented through vringh and workqueue. The device has an on-chip
IOMMU which translates IOVA to PA. For kernel virtio drivers, vDPA
simulator driver provides dma_ops. For vhost driers, set_map() methods
of vdpa_config_ops is implemented to accept mappings from vhost.

Currently, vDPA device simulator will loopback TX traffic to RX. So
the main use case for the device is vDPA feature testing, prototyping
and development.

Note, there's no management API implemented, a vDPA device will be
registered once the module is probed. We need to handle this in the
future development.

Signed-off-by: Jason Wang <jasowang@redhat.com>
---
 drivers/virtio/vdpa/Kconfig             |  19 +
 drivers/virtio/vdpa/Makefile            |   1 +
 drivers/virtio/vdpa/vdpa_sim/Makefile   |   2 +
 drivers/virtio/vdpa/vdpa_sim/vdpa_sim.c | 629 ++++++++++++++++++++++++
 4 files changed, 651 insertions(+)
 create mode 100644 drivers/virtio/vdpa/vdpa_sim/Makefile
 create mode 100644 drivers/virtio/vdpa/vdpa_sim/vdpa_sim.c

diff --git a/drivers/virtio/vdpa/Kconfig b/drivers/virtio/vdpa/Kconfig
index 351617723d12..ae204465964e 100644
--- a/drivers/virtio/vdpa/Kconfig
+++ b/drivers/virtio/vdpa/Kconfig
@@ -5,3 +5,22 @@ config VDPA
 	  Enable this module to support vDPA device that uses a
 	  datapath which complies with virtio specifications with
 	  vendor specific control path.
+
+menuconfig VDPA_MENU
+	bool "VDPA drivers"
+	default n
+
+if VDPA_MENU
+
+config VDPA_SIM
+	tristate "vDPA device simulator"
+	depends on RUNTIME_TESTING_MENU
+	select VDPA
+	select VHOST_RING
+	default n
+	help
+	  vDPA networking device simulator which loop TX traffic back
+	  to RX. This device is used for testing, prototyping and
+	  development of vDPA.
+
+endif # VDPA_MENU
diff --git a/drivers/virtio/vdpa/Makefile b/drivers/virtio/vdpa/Makefile
index ee6a35e8a4fb..3814af8e097b 100644
--- a/drivers/virtio/vdpa/Makefile
+++ b/drivers/virtio/vdpa/Makefile
@@ -1,2 +1,3 @@
 # SPDX-License-Identifier: GPL-2.0
 obj-$(CONFIG_VDPA) += vdpa.o
+obj-$(CONFIG_VDPA_SIM) += vdpa_sim/
diff --git a/drivers/virtio/vdpa/vdpa_sim/Makefile b/drivers/virtio/vdpa/vdpa_sim/Makefile
new file mode 100644
index 000000000000..b40278f65e04
--- /dev/null
+++ b/drivers/virtio/vdpa/vdpa_sim/Makefile
@@ -0,0 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0
+obj-$(CONFIG_VDPA_SIM) += vdpa_sim.o
diff --git a/drivers/virtio/vdpa/vdpa_sim/vdpa_sim.c b/drivers/virtio/vdpa/vdpa_sim/vdpa_sim.c
new file mode 100644
index 000000000000..6e8a0cf2fdeb
--- /dev/null
+++ b/drivers/virtio/vdpa/vdpa_sim/vdpa_sim.c
@@ -0,0 +1,629 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * VDPA networking device simulator.
+ *
+ * Copyright (c) 2020, Red Hat Inc. All rights reserved.
+ *     Author: Jason Wang <jasowang@redhat.com>
+ *
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/fs.h>
+#include <linux/poll.h>
+#include <linux/slab.h>
+#include <linux/sched.h>
+#include <linux/wait.h>
+#include <linux/uuid.h>
+#include <linux/iommu.h>
+#include <linux/dma-mapping.h>
+#include <linux/sysfs.h>
+#include <linux/file.h>
+#include <linux/etherdevice.h>
+#include <linux/vringh.h>
+#include <linux/vdpa.h>
+#include <linux/vhost_iotlb.h>
+#include <uapi/linux/virtio_config.h>
+#include <uapi/linux/virtio_net.h>
+
+#define DRV_VERSION  "0.1"
+#define DRV_AUTHOR   "Jason Wang <jasowang@redhat.com>"
+#define DRV_DESC     "vDPA Device Simulator"
+#define DRV_LICENSE  "GPL v2"
+
+struct vdpasim_virtqueue {
+	struct vringh vring;
+	struct vringh_kiov iov;
+	unsigned short head;
+	bool ready;
+	u64 desc_addr;
+	u64 device_addr;
+	u64 driver_addr;
+	u32 num;
+	void *private;
+	irqreturn_t (*cb)(void *data);
+};
+
+#define VDPASIM_QUEUE_ALIGN PAGE_SIZE
+#define VDPASIM_QUEUE_MAX 256
+#define VDPASIM_DEVICE_ID 0x1
+#define VDPASIM_VENDOR_ID 0
+#define VDPASIM_VQ_NUM 0x2
+#define VDPASIM_NAME "vdpasim-netdev"
+
+static u64 vdpasim_features = (1ULL << VIRTIO_F_ANY_LAYOUT) |
+			      (1ULL << VIRTIO_F_VERSION_1)  |
+			      (1ULL << VIRTIO_F_IOMMU_PLATFORM);
+
+/* State of each vdpasim device */
+struct vdpasim {
+	struct vdpa_device vdpa;
+	struct vdpasim_virtqueue vqs[2];
+	struct work_struct work;
+	/* spinlock to synchronize virtqueue state */
+	spinlock_t lock;
+	struct virtio_net_config config;
+	struct vhost_iotlb *iommu;
+	void *buffer;
+	u32 status;
+	u32 generation;
+	u64 features;
+};
+
+static struct vdpasim *vdpasim_dev;
+
+static struct vdpasim *vdpa_to_sim(struct vdpa_device *vdpa)
+{
+	return container_of(vdpa, struct vdpasim, vdpa);
+}
+
+static struct vdpasim *dev_to_sim(struct device *dev)
+{
+	struct vdpa_device *vdpa = dev_to_vdpa(dev);
+
+	return vdpa_to_sim(vdpa);
+}
+
+static void vdpasim_queue_ready(struct vdpasim *vdpasim, unsigned int idx)
+{
+	struct vdpasim_virtqueue *vq = &vdpasim->vqs[idx];
+	int ret;
+
+	ret = vringh_init_iotlb(&vq->vring, vdpasim_features,
+				VDPASIM_QUEUE_MAX, false,
+				(struct vring_desc *)(uintptr_t)vq->desc_addr,
+				(struct vring_avail *)
+				(uintptr_t)vq->driver_addr,
+				(struct vring_used *)
+				(uintptr_t)vq->device_addr);
+}
+
+static void vdpasim_vq_reset(struct vdpasim_virtqueue *vq)
+{
+	vq->ready = 0;
+	vq->desc_addr = 0;
+	vq->driver_addr = 0;
+	vq->device_addr = 0;
+	vq->cb = NULL;
+	vq->private = NULL;
+	vringh_init_iotlb(&vq->vring, vdpasim_features, VDPASIM_QUEUE_MAX,
+			  false, NULL, NULL, NULL);
+}
+
+static void vdpasim_reset(struct vdpasim *vdpasim)
+{
+	int i;
+
+	for (i = 0; i < VDPASIM_VQ_NUM; i++)
+		vdpasim_vq_reset(&vdpasim->vqs[i]);
+
+	vhost_iotlb_reset(vdpasim->iommu);
+
+	vdpasim->features = 0;
+	vdpasim->status = 0;
+	++vdpasim->generation;
+}
+
+static void vdpasim_work(struct work_struct *work)
+{
+	struct vdpasim *vdpasim = container_of(work, struct
+						 vdpasim, work);
+	struct vdpasim_virtqueue *txq = &vdpasim->vqs[1];
+	struct vdpasim_virtqueue *rxq = &vdpasim->vqs[0];
+	size_t read, write, total_write;
+	int err;
+	int pkts = 0;
+
+	spin_lock(&vdpasim->lock);
+
+	if (!(vdpasim->status & VIRTIO_CONFIG_S_DRIVER_OK))
+		goto out;
+
+	if (!txq->ready || !rxq->ready)
+		goto out;
+
+	while (true) {
+		total_write = 0;
+		err = vringh_getdesc_iotlb(&txq->vring, &txq->iov, NULL,
+					   &txq->head, GFP_ATOMIC);
+		if (err <= 0)
+			break;
+
+		err = vringh_getdesc_iotlb(&rxq->vring, NULL, &rxq->iov,
+					   &rxq->head, GFP_ATOMIC);
+		if (err <= 0) {
+			vringh_complete_iotlb(&txq->vring, txq->head, 0);
+			break;
+		}
+
+		while (true) {
+			read = vringh_iov_pull_iotlb(&txq->vring, &txq->iov,
+						     vdpasim->buffer,
+						     PAGE_SIZE);
+			if (read <= 0)
+				break;
+
+			write = vringh_iov_push_iotlb(&rxq->vring, &rxq->iov,
+						      vdpasim->buffer, read);
+			if (write <= 0)
+				break;
+
+			total_write += write;
+		}
+
+		/* Make sure data is wrote before advancing index */
+		smp_wmb();
+
+		vringh_complete_iotlb(&txq->vring, txq->head, 0);
+		vringh_complete_iotlb(&rxq->vring, rxq->head, total_write);
+
+		/* Make sure used is visible before rasing the interrupt. */
+		smp_wmb();
+
+		local_bh_disable();
+		if (txq->cb)
+			txq->cb(txq->private);
+		if (rxq->cb)
+			rxq->cb(rxq->private);
+		local_bh_enable();
+
+		if (++pkts > 4) {
+			schedule_work(&vdpasim->work);
+			goto out;
+		}
+	}
+
+out:
+	spin_unlock(&vdpasim->lock);
+}
+
+static int dir_to_perm(enum dma_data_direction dir)
+{
+	int perm = -EFAULT;
+
+	switch (dir) {
+	case DMA_FROM_DEVICE:
+		perm = VHOST_MAP_WO;
+		break;
+	case DMA_TO_DEVICE:
+		perm = VHOST_MAP_RO;
+		break;
+	case DMA_BIDIRECTIONAL:
+		perm = VHOST_MAP_RW;
+		break;
+	default:
+		break;
+	}
+
+	return perm;
+}
+
+static dma_addr_t vdpasim_map_page(struct device *dev, struct page *page,
+				   unsigned long offset, size_t size,
+				   enum dma_data_direction dir,
+				   unsigned long attrs)
+{
+	struct vdpasim *vdpasim = dev_to_sim(dev);
+	struct vhost_iotlb *iommu = vdpasim->iommu;
+	u64 pa = (page_to_pfn(page) << PAGE_SHIFT) + offset;
+	int ret, perm = dir_to_perm(dir);
+
+	if (perm < 0)
+		return DMA_MAPPING_ERROR;
+
+	/* For simplicity, use identical mapping to avoid e.g iova
+	 * allocator.
+	 */
+	ret = vhost_iotlb_add_range(iommu, pa, pa + size - 1,
+				    pa, dir_to_perm(dir));
+	if (ret)
+		return DMA_MAPPING_ERROR;
+
+	return (dma_addr_t)(pa);
+}
+
+static void vdpasim_unmap_page(struct device *dev, dma_addr_t dma_addr,
+			       size_t size, enum dma_data_direction dir,
+			       unsigned long attrs)
+{
+	struct vdpasim *vdpasim = dev_to_sim(dev);
+	struct vhost_iotlb *iommu = vdpasim->iommu;
+
+	vhost_iotlb_del_range(iommu, (u64)dma_addr,
+			      (u64)dma_addr + size - 1);
+}
+
+static void *vdpasim_alloc_coherent(struct device *dev, size_t size,
+				    dma_addr_t *dma_addr, gfp_t flag,
+				    unsigned long attrs)
+{
+	struct vdpasim *vdpasim = dev_to_sim(dev);
+	struct vhost_iotlb *iommu = vdpasim->iommu;
+	void *addr = kmalloc(size, flag);
+	int ret;
+
+	if (!addr)
+		*dma_addr = DMA_MAPPING_ERROR;
+	else {
+		u64 pa = virt_to_phys(addr);
+
+		ret = vhost_iotlb_add_range(iommu, (u64)pa,
+					    (u64)pa + size - 1,
+					    pa, VHOST_MAP_RW);
+		if (ret) {
+			*dma_addr = DMA_MAPPING_ERROR;
+			kfree(addr);
+			addr = NULL;
+		} else
+			*dma_addr = (dma_addr_t)pa;
+	}
+
+	return addr;
+}
+
+static void vdpasim_free_coherent(struct device *dev, size_t size,
+				  void *vaddr, dma_addr_t dma_addr,
+				  unsigned long attrs)
+{
+	struct vdpasim *vdpasim = dev_to_sim(dev);
+	struct vhost_iotlb *iommu = vdpasim->iommu;
+
+	vhost_iotlb_del_range(iommu, (u64)dma_addr,
+			      (u64)dma_addr + size - 1);
+	kfree(phys_to_virt((uintptr_t)dma_addr));
+}
+
+static const struct dma_map_ops vdpasim_dma_ops = {
+	.map_page = vdpasim_map_page,
+	.unmap_page = vdpasim_unmap_page,
+	.alloc = vdpasim_alloc_coherent,
+	.free = vdpasim_free_coherent,
+};
+
+static const struct vdpa_config_ops vdpasim_net_config_ops;
+
+static struct vdpasim *vdpasim_create(void)
+{
+	struct virtio_net_config *config;
+	struct vdpasim *vdpasim;
+	struct device *dev;
+	int ret = -ENOMEM;
+
+	vdpasim = vdpa_alloc_device(struct vdpasim, vdpa, NULL,
+				    &vdpasim_net_config_ops);
+	if (!vdpasim)
+		goto err_alloc;
+
+	INIT_WORK(&vdpasim->work, vdpasim_work);
+	spin_lock_init(&vdpasim->lock);
+
+	dev = &vdpasim->vdpa.dev;
+	dev->coherent_dma_mask = DMA_BIT_MASK(64);
+	set_dma_ops(dev, &vdpasim_dma_ops);
+
+	vdpasim->iommu = vhost_iotlb_alloc(2048, 0);
+	if (!vdpasim->iommu)
+		goto err_iommu;
+
+	vdpasim->buffer = kmalloc(PAGE_SIZE, GFP_KERNEL);
+	if (!vdpasim->buffer)
+		goto err_iommu;
+
+	config = &vdpasim->config;
+	config->mtu = 1500;
+	config->status = VIRTIO_NET_S_LINK_UP;
+	eth_random_addr(config->mac);
+
+	vringh_set_iotlb(&vdpasim->vqs[0].vring, vdpasim->iommu);
+	vringh_set_iotlb(&vdpasim->vqs[1].vring, vdpasim->iommu);
+
+	vdpasim->vdpa.dma_dev = dev;
+	ret = vdpa_register_device(&vdpasim->vdpa);
+	if (ret)
+		goto err_iommu;
+
+	return vdpasim;
+
+err_iommu:
+	put_device(dev);
+err_alloc:
+	return ERR_PTR(ret);
+}
+
+static int vdpasim_set_vq_address(struct vdpa_device *vdpa, u16 idx,
+				  u64 desc_area, u64 driver_area,
+				  u64 device_area)
+{
+	struct vdpasim *vdpasim = vdpa_to_sim(vdpa);
+	struct vdpasim_virtqueue *vq = &vdpasim->vqs[idx];
+
+	vq->desc_addr = desc_area;
+	vq->driver_addr = driver_area;
+	vq->device_addr = device_area;
+
+	return 0;
+}
+
+static void vdpasim_set_vq_num(struct vdpa_device *vdpa, u16 idx, u32 num)
+{
+	struct vdpasim *vdpasim = vdpa_to_sim(vdpa);
+	struct vdpasim_virtqueue *vq = &vdpasim->vqs[idx];
+
+	vq->num = num;
+}
+
+static void vdpasim_kick_vq(struct vdpa_device *vdpa, u16 idx)
+{
+	struct vdpasim *vdpasim = vdpa_to_sim(vdpa);
+	struct vdpasim_virtqueue *vq = &vdpasim->vqs[idx];
+
+	if (vq->ready)
+		schedule_work(&vdpasim->work);
+}
+
+static void vdpasim_set_vq_cb(struct vdpa_device *vdpa, u16 idx,
+			      struct vdpa_callback *cb)
+{
+	struct vdpasim *vdpasim = vdpa_to_sim(vdpa);
+	struct vdpasim_virtqueue *vq = &vdpasim->vqs[idx];
+
+	vq->cb = cb->callback;
+	vq->private = cb->private;
+}
+
+static void vdpasim_set_vq_ready(struct vdpa_device *vdpa, u16 idx, bool ready)
+{
+	struct vdpasim *vdpasim = vdpa_to_sim(vdpa);
+	struct vdpasim_virtqueue *vq = &vdpasim->vqs[idx];
+
+	spin_lock(&vdpasim->lock);
+	vq->ready = ready;
+	if (vq->ready)
+		vdpasim_queue_ready(vdpasim, idx);
+	spin_unlock(&vdpasim->lock);
+}
+
+static bool vdpasim_get_vq_ready(struct vdpa_device *vdpa, u16 idx)
+{
+	struct vdpasim *vdpasim = vdpa_to_sim(vdpa);
+	struct vdpasim_virtqueue *vq = &vdpasim->vqs[idx];
+
+	return vq->ready;
+}
+
+static int vdpasim_set_vq_state(struct vdpa_device *vdpa, u16 idx, u64 state)
+{
+	struct vdpasim *vdpasim = vdpa_to_sim(vdpa);
+	struct vdpasim_virtqueue *vq = &vdpasim->vqs[idx];
+	struct vringh *vrh = &vq->vring;
+
+	spin_lock(&vdpasim->lock);
+	vrh->last_avail_idx = state;
+	spin_unlock(&vdpasim->lock);
+
+	return 0;
+}
+
+static u64 vdpasim_get_vq_state(struct vdpa_device *vdpa, u16 idx)
+{
+	struct vdpasim *vdpasim = vdpa_to_sim(vdpa);
+	struct vdpasim_virtqueue *vq = &vdpasim->vqs[idx];
+	struct vringh *vrh = &vq->vring;
+
+	return vrh->last_avail_idx;
+}
+
+static u16 vdpasim_get_vq_align(struct vdpa_device *vdpa)
+{
+	return VDPASIM_QUEUE_ALIGN;
+}
+
+static u64 vdpasim_get_features(struct vdpa_device *vdpa)
+{
+	return vdpasim_features;
+}
+
+static int vdpasim_set_features(struct vdpa_device *vdpa, u64 features)
+{
+	struct vdpasim *vdpasim = vdpa_to_sim(vdpa);
+
+	/* DMA mapping must be done by driver */
+	if (!(features & (1ULL << VIRTIO_F_IOMMU_PLATFORM)))
+		return -EINVAL;
+
+	vdpasim->features = features & vdpasim_features;
+
+	return 0;
+}
+
+static void vdpasim_set_config_cb(struct vdpa_device *vdpa,
+				  struct vdpa_callback *cb)
+{
+	/* We don't support config interrupt */
+}
+
+static u16 vdpasim_get_vq_num_max(struct vdpa_device *vdpa)
+{
+	return VDPASIM_QUEUE_MAX;
+}
+
+static u32 vdpasim_get_device_id(struct vdpa_device *vdpa)
+{
+	return VDPASIM_DEVICE_ID;
+}
+
+static u32 vdpasim_get_vendor_id(struct vdpa_device *vdpa)
+{
+	return VDPASIM_VENDOR_ID;
+}
+
+static u8 vdpasim_get_status(struct vdpa_device *vdpa)
+{
+	struct vdpasim *vdpasim = vdpa_to_sim(vdpa);
+	u8 status;
+
+	spin_lock(&vdpasim->lock);
+	status = vdpasim->status;
+	spin_unlock(&vdpasim->lock);
+
+	return vdpasim->status;
+}
+
+static void vdpasim_set_status(struct vdpa_device *vdpa, u8 status)
+{
+	struct vdpasim *vdpasim = vdpa_to_sim(vdpa);
+
+	spin_lock(&vdpasim->lock);
+	vdpasim->status = status;
+	if (status == 0)
+		vdpasim_reset(vdpasim);
+	spin_unlock(&vdpasim->lock);
+}
+
+static void vdpasim_get_config(struct vdpa_device *vdpa, unsigned int offset,
+			     void *buf, unsigned int len)
+{
+	struct vdpasim *vdpasim = vdpa_to_sim(vdpa);
+
+	if (offset + len < sizeof(struct virtio_net_config))
+		memcpy(buf, &vdpasim->config + offset, len);
+}
+
+static void vdpasim_set_config(struct vdpa_device *vdpa, unsigned int offset,
+			     const void *buf, unsigned int len)
+{
+	/* No writable config supportted by vdpasim */
+}
+
+static u32 vdpasim_get_generation(struct vdpa_device *vdpa)
+{
+	struct vdpasim *vdpasim = vdpa_to_sim(vdpa);
+
+	return vdpasim->generation;
+}
+
+static int vdpasim_set_map(struct vdpa_device *vdpa,
+			   struct vhost_iotlb *iotlb)
+{
+	struct vdpasim *vdpasim = vdpa_to_sim(vdpa);
+	struct vhost_iotlb_map *map;
+	u64 start = 0ULL, last = 0ULL - 1;
+	int ret;
+
+	vhost_iotlb_reset(vdpasim->iommu);
+
+	for (map = vhost_iotlb_itree_first(iotlb, start, last); map;
+	     map = vhost_iotlb_itree_next(map, start, last)) {
+		ret = vhost_iotlb_add_range(vdpasim->iommu, map->start,
+					    map->last, map->addr, map->perm);
+		if (ret)
+			goto err;
+	}
+	return 0;
+
+err:
+	vhost_iotlb_reset(vdpasim->iommu);
+	return ret;
+}
+
+static int vdpasim_dma_map(struct vdpa_device *vdpa, u64 iova, u64 size,
+			   u64 pa, u32 perm)
+{
+	struct vdpasim *vdpasim = vdpa_to_sim(vdpa);
+
+	return vhost_iotlb_add_range(vdpasim->iommu, iova,
+				     iova + size - 1, pa, perm);
+}
+
+static int vdpasim_dma_unmap(struct vdpa_device *vdpa, u64 iova, u64 size)
+{
+	struct vdpasim *vdpasim = vdpa_to_sim(vdpa);
+
+	vhost_iotlb_del_range(vdpasim->iommu, iova, iova + size - 1);
+
+	return 0;
+}
+
+static void vdpasim_free(struct vdpa_device *vdpa)
+{
+	struct vdpasim *vdpasim = vdpa_to_sim(vdpa);
+
+	cancel_work_sync(&vdpasim->work);
+	kfree(vdpasim->buffer);
+	if (vdpasim->iommu)
+		vhost_iotlb_free(vdpasim->iommu);
+}
+
+static const struct vdpa_config_ops vdpasim_net_config_ops = {
+	.set_vq_address         = vdpasim_set_vq_address,
+	.set_vq_num             = vdpasim_set_vq_num,
+	.kick_vq                = vdpasim_kick_vq,
+	.set_vq_cb              = vdpasim_set_vq_cb,
+	.set_vq_ready           = vdpasim_set_vq_ready,
+	.get_vq_ready           = vdpasim_get_vq_ready,
+	.set_vq_state           = vdpasim_set_vq_state,
+	.get_vq_state           = vdpasim_get_vq_state,
+	.get_vq_align           = vdpasim_get_vq_align,
+	.get_features           = vdpasim_get_features,
+	.set_features           = vdpasim_set_features,
+	.set_config_cb          = vdpasim_set_config_cb,
+	.get_vq_num_max         = vdpasim_get_vq_num_max,
+	.get_device_id          = vdpasim_get_device_id,
+	.get_vendor_id          = vdpasim_get_vendor_id,
+	.get_status             = vdpasim_get_status,
+	.set_status             = vdpasim_set_status,
+	.get_config             = vdpasim_get_config,
+	.set_config             = vdpasim_set_config,
+	.get_generation         = vdpasim_get_generation,
+	.set_map                = vdpasim_set_map,
+	.dma_map                = vdpasim_dma_map,
+	.dma_unmap              = vdpasim_dma_unmap,
+	.free                   = vdpasim_free,
+};
+
+static int __init vdpasim_dev_init(void)
+{
+	vdpasim_dev = vdpasim_create();
+
+	if (!IS_ERR(vdpasim_dev))
+		return 0;
+
+	return PTR_ERR(vdpasim_dev);
+}
+
+static void __exit vdpasim_dev_exit(void)
+{
+	struct vdpa_device *vdpa = &vdpasim_dev->vdpa;
+
+	vdpa_unregister_device(vdpa);
+}
+
+module_init(vdpasim_dev_init)
+module_exit(vdpasim_dev_exit)
+
+MODULE_VERSION(DRV_VERSION);
+MODULE_LICENSE(DRV_LICENSE);
+MODULE_AUTHOR(DRV_AUTHOR);
+MODULE_DESCRIPTION(DRV_DESC);
-- 
2.20.1


^ permalink raw reply	[flat|nested] 38+ messages in thread

* [PATCH V9 9/9] virtio: Intel IFC VF driver for VDPA
  2020-03-26 14:01 [PATCH V9 0/9] vDPA support Jason Wang
                   ` (7 preceding siblings ...)
  2020-03-26 14:01 ` [PATCH V9 8/9] vdpasim: vDPA device simulator Jason Wang
@ 2020-03-26 14:01 ` Jason Wang
  2020-03-29 11:07 ` [PATCH V9 0/9] vDPA support Michael S. Tsirkin
  9 siblings, 0 replies; 38+ messages in thread
From: Jason Wang @ 2020-03-26 14:01 UTC (permalink / raw)
  To: mst, linux-kernel, kvm, virtualization, netdev
  Cc: jgg, maxime.coquelin, cunming.liang, zhihong.wang, rob.miller,
	xiao.w.wang, lingshan.zhu, eperezma, lulu, parav, kevin.tian,
	stefanha, rdunlap, hch, aadam, jiri, shahafs, hanand, mhabets,
	gdawar, saugatm, vmireyno, zhangweining, Bie Tiwei, Jason Wang

From: Zhu Lingshan <lingshan.zhu@intel.com>

This commit introduced two layers to drive IFC VF:

(1) ifcvf_base layer, which handles IFC VF NIC hardware operations and
    configurations.

(2) ifcvf_main layer, which complies to VDPA bus framework,
    implemented device operations for VDPA bus, handles device probe,
    bus attaching, vring operations, etc.

Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
Signed-off-by: Bie Tiwei <tiwei.bie@intel.com>
Signed-off-by: Wang Xiao <xiao.w.wang@intel.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
---
 drivers/virtio/vdpa/Kconfig            |  11 +
 drivers/virtio/vdpa/Makefile           |   1 +
 drivers/virtio/vdpa/ifcvf/Makefile     |   3 +
 drivers/virtio/vdpa/ifcvf/ifcvf_base.c | 389 ++++++++++++++++++++++
 drivers/virtio/vdpa/ifcvf/ifcvf_base.h | 118 +++++++
 drivers/virtio/vdpa/ifcvf/ifcvf_main.c | 435 +++++++++++++++++++++++++
 6 files changed, 957 insertions(+)
 create mode 100644 drivers/virtio/vdpa/ifcvf/Makefile
 create mode 100644 drivers/virtio/vdpa/ifcvf/ifcvf_base.c
 create mode 100644 drivers/virtio/vdpa/ifcvf/ifcvf_base.h
 create mode 100644 drivers/virtio/vdpa/ifcvf/ifcvf_main.c

diff --git a/drivers/virtio/vdpa/Kconfig b/drivers/virtio/vdpa/Kconfig
index ae204465964e..7db1460104b7 100644
--- a/drivers/virtio/vdpa/Kconfig
+++ b/drivers/virtio/vdpa/Kconfig
@@ -23,4 +23,15 @@ config VDPA_SIM
 	  to RX. This device is used for testing, prototyping and
 	  development of vDPA.
 
+config IFCVF
+	tristate "Intel IFC VF VDPA driver"
+	depends on PCI_MSI
+	select VDPA
+	default n
+	help
+	  This kernel module can drive Intel IFC VF NIC to offload
+	  virtio dataplane traffic to hardware.
+	  To compile this driver as a module, choose M here: the module will
+	  be called ifcvf.
+
 endif # VDPA_MENU
diff --git a/drivers/virtio/vdpa/Makefile b/drivers/virtio/vdpa/Makefile
index 3814af8e097b..8bbb686ca7a2 100644
--- a/drivers/virtio/vdpa/Makefile
+++ b/drivers/virtio/vdpa/Makefile
@@ -1,3 +1,4 @@
 # SPDX-License-Identifier: GPL-2.0
 obj-$(CONFIG_VDPA) += vdpa.o
 obj-$(CONFIG_VDPA_SIM) += vdpa_sim/
+obj-$(CONFIG_IFCVF)    += ifcvf/
diff --git a/drivers/virtio/vdpa/ifcvf/Makefile b/drivers/virtio/vdpa/ifcvf/Makefile
new file mode 100644
index 000000000000..d709915995ab
--- /dev/null
+++ b/drivers/virtio/vdpa/ifcvf/Makefile
@@ -0,0 +1,3 @@
+# SPDX-License-Identifier: GPL-2.0
+obj-$(CONFIG_IFCVF) += ifcvf.o
+ifcvf-$(CONFIG_IFCVF) += ifcvf_main.o ifcvf_base.o
diff --git a/drivers/virtio/vdpa/ifcvf/ifcvf_base.c b/drivers/virtio/vdpa/ifcvf/ifcvf_base.c
new file mode 100644
index 000000000000..b61b06ea26d3
--- /dev/null
+++ b/drivers/virtio/vdpa/ifcvf/ifcvf_base.c
@@ -0,0 +1,389 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Intel IFC VF NIC driver for virtio dataplane offloading
+ *
+ * Copyright (C) 2020 Intel Corporation.
+ *
+ * Author: Zhu Lingshan <lingshan.zhu@intel.com>
+ *
+ */
+
+#include "ifcvf_base.h"
+
+static inline u8 ifc_ioread8(u8 __iomem *addr)
+{
+	return ioread8(addr);
+}
+static inline u16 ifc_ioread16 (__le16 __iomem *addr)
+{
+	return ioread16(addr);
+}
+
+static inline u32 ifc_ioread32(__le32 __iomem *addr)
+{
+	return ioread32(addr);
+}
+
+static inline void ifc_iowrite8(u8 value, u8 __iomem *addr)
+{
+	iowrite8(value, addr);
+}
+
+static inline void ifc_iowrite16(u16 value, __le16 __iomem *addr)
+{
+	iowrite16(value, addr);
+}
+
+static inline void ifc_iowrite32(u32 value, __le32 __iomem *addr)
+{
+	iowrite32(value, addr);
+}
+
+static void ifc_iowrite64_twopart(u64 val,
+				  __le32 __iomem *lo, __le32 __iomem *hi)
+{
+	ifc_iowrite32((u32)val, lo);
+	ifc_iowrite32(val >> 32, hi);
+}
+
+struct ifcvf_adapter *vf_to_adapter(struct ifcvf_hw *hw)
+{
+	return container_of(hw, struct ifcvf_adapter, vf);
+}
+
+static void __iomem *get_cap_addr(struct ifcvf_hw *hw,
+				  struct virtio_pci_cap *cap)
+{
+	struct ifcvf_adapter *ifcvf;
+	struct pci_dev *pdev;
+	u32 length, offset;
+	u8 bar;
+
+	length = le32_to_cpu(cap->length);
+	offset = le32_to_cpu(cap->offset);
+	bar = cap->bar;
+
+	ifcvf= vf_to_adapter(hw);
+	pdev = ifcvf->pdev;
+
+	if (bar >= IFCVF_PCI_MAX_RESOURCE) {
+		IFCVF_DBG(pdev,
+			  "Invalid bar number %u to get capabilities\n", bar);
+		return NULL;
+	}
+
+	if (offset + length > pci_resource_len(pdev, bar)) {
+		IFCVF_DBG(pdev,
+			  "offset(%u) + len(%u) overflows bar%u's capability\n",
+			  offset, length, bar);
+		return NULL;
+	}
+
+	return hw->base[bar] + offset;
+}
+
+static int ifcvf_read_config_range(struct pci_dev *dev,
+				   uint32_t *val, int size, int where)
+{
+	int ret, i;
+
+	for (i = 0; i < size; i += 4) {
+		ret = pci_read_config_dword(dev, where + i, val + i / 4);
+		if (ret < 0)
+			return ret;
+	}
+
+	return 0;
+}
+
+int ifcvf_init_hw(struct ifcvf_hw *hw, struct pci_dev *pdev)
+{
+	struct virtio_pci_cap cap;
+	u16 notify_off;
+	int ret;
+	u8 pos;
+	u32 i;
+
+	ret = pci_read_config_byte(pdev, PCI_CAPABILITY_LIST, &pos);
+	if (ret < 0) {
+		IFCVF_ERR(pdev, "Failed to read PCI capability list\n");
+		return -EIO;
+	}
+
+	while (pos) {
+		ret = ifcvf_read_config_range(pdev, (u32 *)&cap,
+					      sizeof(cap), pos);
+		if (ret < 0) {
+			IFCVF_ERR(pdev,
+				  "Failed to get PCI capability at %x\n", pos);
+			break;
+		}
+
+		if (cap.cap_vndr != PCI_CAP_ID_VNDR)
+			goto next;
+
+		switch (cap.cfg_type) {
+		case VIRTIO_PCI_CAP_COMMON_CFG:
+			hw->common_cfg = get_cap_addr(hw, &cap);
+			IFCVF_DBG(pdev, "hw->common_cfg = %p\n",
+				  hw->common_cfg);
+			break;
+		case VIRTIO_PCI_CAP_NOTIFY_CFG:
+			pci_read_config_dword(pdev, pos + sizeof(cap),
+					      &hw->notify_off_multiplier);
+			hw->notify_bar = cap.bar;
+			hw->notify_base = get_cap_addr(hw, &cap);
+			IFCVF_DBG(pdev, "hw->notify_base = %p\n",
+				  hw->notify_base);
+			break;
+		case VIRTIO_PCI_CAP_ISR_CFG:
+			hw->isr = get_cap_addr(hw, &cap);
+			IFCVF_DBG(pdev, "hw->isr = %p\n", hw->isr);
+			break;
+		case VIRTIO_PCI_CAP_DEVICE_CFG:
+			hw->net_cfg = get_cap_addr(hw, &cap);
+			IFCVF_DBG(pdev, "hw->net_cfg = %p\n", hw->net_cfg);
+			break;
+		}
+
+next:
+		pos = cap.cap_next;
+	}
+
+	if (hw->common_cfg == NULL || hw->notify_base == NULL ||
+	    hw->isr == NULL || hw->net_cfg == NULL) {
+		IFCVF_ERR(pdev, "Incomplete PCI capabilities\n");
+		return -EIO;
+	}
+
+	for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++) {
+		ifc_iowrite16(i, &hw->common_cfg->queue_select);
+		notify_off = ifc_ioread16(&hw->common_cfg->queue_notify_off);
+		hw->vring[i].notify_addr = hw->notify_base +
+			notify_off * hw->notify_off_multiplier;
+	}
+
+	hw->lm_cfg = hw->base[IFCVF_LM_BAR];
+
+	IFCVF_DBG(pdev,
+		  "PCI capability mapping: common cfg: %p, notify base: %p\n, isr cfg: %p, device cfg: %p, multiplier: %u\n",
+		  hw->common_cfg, hw->notify_base, hw->isr,
+		  hw->net_cfg, hw->notify_off_multiplier);
+
+	return 0;
+}
+
+u8 ifcvf_get_status(struct ifcvf_hw *hw)
+{
+	return ifc_ioread8(&hw->common_cfg->device_status);
+}
+
+void ifcvf_set_status(struct ifcvf_hw *hw, u8 status)
+{
+	ifc_iowrite8(status, &hw->common_cfg->device_status);
+}
+
+void ifcvf_reset(struct ifcvf_hw *hw)
+{
+	ifcvf_set_status(hw, 0);
+	/* flush set_status, make sure VF is stopped, reset */
+	ifcvf_get_status(hw);
+}
+
+static void ifcvf_add_status(struct ifcvf_hw *hw, u8 status)
+{
+	if (status != 0)
+		status |= ifcvf_get_status(hw);
+
+	ifcvf_set_status(hw, status);
+	ifcvf_get_status(hw);
+}
+
+u64 ifcvf_get_features(struct ifcvf_hw *hw)
+{
+	struct virtio_pci_common_cfg __iomem *cfg = hw->common_cfg;
+	u32 features_lo, features_hi;
+
+	ifc_iowrite32(0, &cfg->device_feature_select);
+	features_lo = ifc_ioread32(&cfg->device_feature);
+
+	ifc_iowrite32(1, &cfg->device_feature_select);
+	features_hi = ifc_ioread32(&cfg->device_feature);
+
+	return ((u64)features_hi << 32) | features_lo;
+}
+
+void ifcvf_read_net_config(struct ifcvf_hw *hw, u64 offset,
+			   void *dst, int length)
+{
+	u8 old_gen, new_gen, *p;
+	int i;
+
+	WARN_ON(offset + length > sizeof(struct virtio_net_config));
+	do {
+		old_gen = ifc_ioread8(&hw->common_cfg->config_generation);
+		p = dst;
+		for (i = 0; i < length; i++)
+			*p++ = ifc_ioread8(hw->net_cfg + offset + i);
+
+		new_gen = ifc_ioread8(&hw->common_cfg->config_generation);
+	} while (old_gen != new_gen);
+}
+
+void ifcvf_write_net_config(struct ifcvf_hw *hw, u64 offset,
+			    const void *src, int length)
+{
+	const u8 *p;
+	int i;
+
+	p = src;
+	WARN_ON(offset + length > sizeof(struct virtio_net_config));
+	for (i = 0; i < length; i++)
+		ifc_iowrite8(*p++, hw->net_cfg + offset + i);
+}
+
+static void ifcvf_set_features(struct ifcvf_hw *hw, u64 features)
+{
+	struct virtio_pci_common_cfg __iomem *cfg = hw->common_cfg;
+
+	ifc_iowrite32(0, &cfg->guest_feature_select);
+	ifc_iowrite32((u32)features, &cfg->guest_feature);
+
+	ifc_iowrite32(1, &cfg->guest_feature_select);
+	ifc_iowrite32(features >> 32, &cfg->guest_feature);
+}
+
+static int ifcvf_config_features(struct ifcvf_hw *hw)
+{
+	struct ifcvf_adapter *ifcvf;
+
+	ifcvf = vf_to_adapter(hw);
+	ifcvf_set_features(hw, hw->req_features);
+	ifcvf_add_status(hw, VIRTIO_CONFIG_S_FEATURES_OK);
+
+	if (!(ifcvf_get_status(hw) & VIRTIO_CONFIG_S_FEATURES_OK)) {
+		IFCVF_ERR(ifcvf->pdev, "Failed to set FEATURES_OK status\n");
+		return -EIO;
+	}
+
+	return 0;
+}
+
+u64 ifcvf_get_vq_state(struct ifcvf_hw *hw, u16 qid)
+{
+	struct ifcvf_lm_cfg __iomem *ifcvf_lm;
+	void __iomem *avail_idx_addr;
+	u16 last_avail_idx;
+	u32 q_pair_id;
+
+	ifcvf_lm = (struct ifcvf_lm_cfg __iomem *)hw->lm_cfg;
+	q_pair_id = qid / (IFCVF_MAX_QUEUE_PAIRS * 2);
+	avail_idx_addr = &ifcvf_lm->vring_lm_cfg[q_pair_id].idx_addr[qid % 2];
+	last_avail_idx = ifc_ioread16(avail_idx_addr);
+
+	return last_avail_idx;
+}
+
+int ifcvf_set_vq_state(struct ifcvf_hw *hw, u16 qid, u64 num)
+{
+	struct ifcvf_lm_cfg __iomem *ifcvf_lm;
+	void __iomem *avail_idx_addr;
+	u32 q_pair_id;
+
+	ifcvf_lm = (struct ifcvf_lm_cfg __iomem *)hw->lm_cfg;
+	q_pair_id = qid / (IFCVF_MAX_QUEUE_PAIRS * 2);
+	avail_idx_addr = &ifcvf_lm->vring_lm_cfg[q_pair_id].idx_addr[qid % 2];
+	hw->vring[qid].last_avail_idx = num;
+	ifc_iowrite16(num, avail_idx_addr);
+
+	return 0;
+}
+
+static int ifcvf_hw_enable(struct ifcvf_hw *hw)
+{
+	struct ifcvf_lm_cfg __iomem *ifcvf_lm;
+	struct virtio_pci_common_cfg __iomem *cfg;
+	struct ifcvf_adapter *ifcvf;
+	u32 i;
+
+	ifcvf_lm = (struct ifcvf_lm_cfg __iomem *)hw->lm_cfg;
+	ifcvf = vf_to_adapter(hw);
+	cfg = hw->common_cfg;
+	ifc_iowrite16(IFCVF_MSI_CONFIG_OFF, &cfg->msix_config);
+
+	if (ifc_ioread16(&cfg->msix_config) == VIRTIO_MSI_NO_VECTOR) {
+		IFCVF_ERR(ifcvf->pdev, "No msix vector for device config\n");
+		return -EINVAL;
+	}
+
+	for (i = 0; i < hw->nr_vring; i++) {
+		if (!hw->vring[i].ready)
+			break;
+
+		ifc_iowrite16(i, &cfg->queue_select);
+		ifc_iowrite64_twopart(hw->vring[i].desc, &cfg->queue_desc_lo,
+				     &cfg->queue_desc_hi);
+		ifc_iowrite64_twopart(hw->vring[i].avail, &cfg->queue_avail_lo,
+				      &cfg->queue_avail_hi);
+		ifc_iowrite64_twopart(hw->vring[i].used, &cfg->queue_used_lo,
+				     &cfg->queue_used_hi);
+		ifc_iowrite16(hw->vring[i].size, &cfg->queue_size);
+		ifc_iowrite16(i + IFCVF_MSI_QUEUE_OFF, &cfg->queue_msix_vector);
+
+		if (ifc_ioread16(&cfg->queue_msix_vector) ==
+		    VIRTIO_MSI_NO_VECTOR) {
+			IFCVF_ERR(ifcvf->pdev,
+				  "No msix vector for queue %u\n", i);
+			return -EINVAL;
+		}
+
+		ifcvf_set_vq_state(hw, i, hw->vring[i].last_avail_idx);
+		ifc_iowrite16(1, &cfg->queue_enable);
+	}
+
+	return 0;
+}
+
+static void ifcvf_hw_disable(struct ifcvf_hw *hw)
+{
+	struct virtio_pci_common_cfg __iomem *cfg;
+	u32 i;
+
+	cfg = hw->common_cfg;
+	ifc_iowrite16(VIRTIO_MSI_NO_VECTOR, &cfg->msix_config);
+
+	for (i = 0; i < hw->nr_vring; i++) {
+		ifc_iowrite16(i, &cfg->queue_select);
+		ifc_iowrite16(VIRTIO_MSI_NO_VECTOR, &cfg->queue_msix_vector);
+	}
+
+	ifc_ioread16(&cfg->queue_msix_vector);
+}
+
+int ifcvf_start_hw(struct ifcvf_hw *hw)
+{
+	ifcvf_reset(hw);
+	ifcvf_add_status(hw, VIRTIO_CONFIG_S_ACKNOWLEDGE);
+	ifcvf_add_status(hw, VIRTIO_CONFIG_S_DRIVER);
+
+	if (ifcvf_config_features(hw) < 0)
+		return -EINVAL;
+
+	if (ifcvf_hw_enable(hw) < 0)
+		return -EINVAL;
+
+	ifcvf_add_status(hw, VIRTIO_CONFIG_S_DRIVER_OK);
+
+	return 0;
+}
+
+void ifcvf_stop_hw(struct ifcvf_hw *hw)
+{
+	ifcvf_hw_disable(hw);
+	ifcvf_reset(hw);
+}
+
+void ifcvf_notify_queue(struct ifcvf_hw *hw, u16 qid)
+{
+	ifc_iowrite16(qid, hw->vring[qid].notify_addr);
+}
diff --git a/drivers/virtio/vdpa/ifcvf/ifcvf_base.h b/drivers/virtio/vdpa/ifcvf/ifcvf_base.h
new file mode 100644
index 000000000000..e80307092351
--- /dev/null
+++ b/drivers/virtio/vdpa/ifcvf/ifcvf_base.h
@@ -0,0 +1,118 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Intel IFC VF NIC driver for virtio dataplane offloading
+ *
+ * Copyright (C) 2020 Intel Corporation.
+ *
+ * Author: Zhu Lingshan <lingshan.zhu@intel.com>
+ *
+ */
+
+#ifndef _IFCVF_H_
+#define _IFCVF_H_
+
+#include <linux/pci.h>
+#include <linux/pci_regs.h>
+#include <linux/vdpa.h>
+#include <uapi/linux/virtio_net.h>
+#include <uapi/linux/virtio_config.h>
+#include <uapi/linux/virtio_pci.h>
+
+#define IFCVF_VENDOR_ID		0x1AF4
+#define IFCVF_DEVICE_ID		0x1041
+#define IFCVF_SUBSYS_VENDOR_ID	0x8086
+#define IFCVF_SUBSYS_DEVICE_ID	0x001A
+
+#define IFCVF_SUPPORTED_FEATURES \
+		((1ULL << VIRTIO_NET_F_MAC)			| \
+		 (1ULL << VIRTIO_F_ANY_LAYOUT)			| \
+		 (1ULL << VIRTIO_F_VERSION_1)			| \
+		 (1ULL << VIRTIO_F_ORDER_PLATFORM)		| \
+		 (1ULL << VIRTIO_F_IOMMU_PLATFORM)		| \
+		 (1ULL << VIRTIO_NET_F_MRG_RXBUF))
+
+/* Only one queue pair for now. */
+#define IFCVF_MAX_QUEUE_PAIRS	1
+
+#define IFCVF_QUEUE_ALIGNMENT	PAGE_SIZE
+#define IFCVF_QUEUE_MAX		32768
+#define IFCVF_MSI_CONFIG_OFF	0
+#define IFCVF_MSI_QUEUE_OFF	1
+#define IFCVF_PCI_MAX_RESOURCE	6
+
+#define IFCVF_LM_CFG_SIZE		0x40
+#define IFCVF_LM_RING_STATE_OFFSET	0x20
+#define IFCVF_LM_BAR			4
+
+#define IFCVF_ERR(pdev, fmt, ...)	dev_err(&pdev->dev, fmt, ##__VA_ARGS__)
+#define IFCVF_DBG(pdev, fmt, ...)	dev_dbg(&pdev->dev, fmt, ##__VA_ARGS__)
+#define IFCVF_INFO(pdev, fmt, ...)	dev_info(&pdev->dev, fmt, ##__VA_ARGS__)
+
+#define ifcvf_private_to_vf(adapter) \
+	(&((struct ifcvf_adapter *)adapter)->vf)
+
+#define IFCVF_MAX_INTR (IFCVF_MAX_QUEUE_PAIRS * 2 + 1)
+
+struct vring_info {
+	u64 desc;
+	u64 avail;
+	u64 used;
+	u16 size;
+	u16 last_avail_idx;
+	bool ready;
+	void __iomem *notify_addr;
+	u32 irq;
+	struct vdpa_callback cb;
+	char msix_name[256];
+};
+
+struct ifcvf_hw {
+	u8 __iomem *isr;
+	/* Live migration */
+	u8 __iomem *lm_cfg;
+	u16 nr_vring;
+	/* Notification bar number */
+	u8 notify_bar;
+	/* Notificaiton bar address */
+	void __iomem *notify_base;
+	u32 notify_off_multiplier;
+	u64 req_features;
+	struct virtio_pci_common_cfg __iomem *common_cfg;
+	void __iomem *net_cfg;
+	struct vring_info vring[IFCVF_MAX_QUEUE_PAIRS * 2];
+	void __iomem * const *base;
+};
+
+struct ifcvf_adapter {
+	struct vdpa_device vdpa;
+	struct pci_dev *pdev;
+	struct ifcvf_hw vf;
+};
+
+struct ifcvf_vring_lm_cfg {
+	u32 idx_addr[2];
+	u8 reserved[IFCVF_LM_CFG_SIZE - 8];
+};
+
+struct ifcvf_lm_cfg {
+	u8 reserved[IFCVF_LM_RING_STATE_OFFSET];
+	struct ifcvf_vring_lm_cfg vring_lm_cfg[IFCVF_MAX_QUEUE_PAIRS];
+};
+
+int ifcvf_init_hw(struct ifcvf_hw *hw, struct pci_dev *dev);
+int ifcvf_start_hw(struct ifcvf_hw *hw);
+void ifcvf_stop_hw(struct ifcvf_hw *hw);
+void ifcvf_notify_queue(struct ifcvf_hw *hw, u16 qid);
+void ifcvf_read_net_config(struct ifcvf_hw *hw, u64 offset,
+			   void *dst, int length);
+void ifcvf_write_net_config(struct ifcvf_hw *hw, u64 offset,
+			    const void *src, int length);
+u8 ifcvf_get_status(struct ifcvf_hw *hw);
+void ifcvf_set_status(struct ifcvf_hw *hw, u8 status);
+void io_write64_twopart(u64 val, u32 *lo, u32 *hi);
+void ifcvf_reset(struct ifcvf_hw *hw);
+u64 ifcvf_get_features(struct ifcvf_hw *hw);
+u64 ifcvf_get_vq_state(struct ifcvf_hw *hw, u16 qid);
+int ifcvf_set_vq_state(struct ifcvf_hw *hw, u16 qid, u64 num);
+struct ifcvf_adapter *vf_to_adapter(struct ifcvf_hw *hw);
+#endif /* _IFCVF_H_ */
diff --git a/drivers/virtio/vdpa/ifcvf/ifcvf_main.c b/drivers/virtio/vdpa/ifcvf/ifcvf_main.c
new file mode 100644
index 000000000000..8d54dc5b08d2
--- /dev/null
+++ b/drivers/virtio/vdpa/ifcvf/ifcvf_main.c
@@ -0,0 +1,435 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Intel IFC VF NIC driver for virtio dataplane offloading
+ *
+ * Copyright (C) 2020 Intel Corporation.
+ *
+ * Author: Zhu Lingshan <lingshan.zhu@intel.com>
+ *
+ */
+
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/sysfs.h>
+#include "ifcvf_base.h"
+
+#define VERSION_STRING  "0.1"
+#define DRIVER_AUTHOR   "Intel Corporation"
+#define IFCVF_DRIVER_NAME       "ifcvf"
+
+static irqreturn_t ifcvf_intr_handler(int irq, void *arg)
+{
+	struct vring_info *vring = arg;
+
+	if (vring->cb.callback)
+		return vring->cb.callback(vring->cb.private);
+
+	return IRQ_HANDLED;
+}
+
+static int ifcvf_start_datapath(void *private)
+{
+	struct ifcvf_hw *vf = ifcvf_private_to_vf(private);
+	struct ifcvf_adapter *ifcvf;
+	u8 status;
+	int ret;
+
+	ifcvf = vf_to_adapter(vf);
+	vf->nr_vring = IFCVF_MAX_QUEUE_PAIRS * 2;
+	ret = ifcvf_start_hw(vf);
+	if (ret < 0) {
+		status = ifcvf_get_status(vf);
+		status |= VIRTIO_CONFIG_S_FAILED;
+		ifcvf_set_status(vf, status);
+	}
+
+	return ret;
+}
+
+static int ifcvf_stop_datapath(void *private)
+{
+	struct ifcvf_hw *vf = ifcvf_private_to_vf(private);
+	int i;
+
+	for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++)
+		vf->vring[i].cb.callback = NULL;
+
+	ifcvf_stop_hw(vf);
+
+	return 0;
+}
+
+static void ifcvf_reset_vring(struct ifcvf_adapter *adapter)
+{
+	struct ifcvf_hw *vf = ifcvf_private_to_vf(adapter);
+	int i;
+
+	for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++) {
+		vf->vring[i].last_avail_idx = 0;
+		vf->vring[i].desc = 0;
+		vf->vring[i].avail = 0;
+		vf->vring[i].used = 0;
+		vf->vring[i].ready = 0;
+		vf->vring[i].cb.callback = NULL;
+		vf->vring[i].cb.private = NULL;
+	}
+
+	ifcvf_reset(vf);
+}
+
+static struct ifcvf_adapter *vdpa_to_adapter(struct vdpa_device *vdpa_dev)
+{
+	return container_of(vdpa_dev, struct ifcvf_adapter, vdpa);
+}
+
+static struct ifcvf_hw *vdpa_to_vf(struct vdpa_device *vdpa_dev)
+{
+	struct ifcvf_adapter *adapter = vdpa_to_adapter(vdpa_dev);
+
+	return &adapter->vf;
+}
+
+static u64 ifcvf_vdpa_get_features(struct vdpa_device *vdpa_dev)
+{
+	struct ifcvf_hw *vf = vdpa_to_vf(vdpa_dev);
+	u64 features;
+
+	features = ifcvf_get_features(vf) & IFCVF_SUPPORTED_FEATURES;
+
+	return features;
+}
+
+static int ifcvf_vdpa_set_features(struct vdpa_device *vdpa_dev, u64 features)
+{
+	struct ifcvf_hw *vf = vdpa_to_vf(vdpa_dev);
+
+	vf->req_features = features;
+
+	return 0;
+}
+
+static u8 ifcvf_vdpa_get_status(struct vdpa_device *vdpa_dev)
+{
+	struct ifcvf_hw *vf = vdpa_to_vf(vdpa_dev);
+
+	return ifcvf_get_status(vf);
+}
+
+static void ifcvf_vdpa_set_status(struct vdpa_device *vdpa_dev, u8 status)
+{
+	struct ifcvf_adapter *adapter;
+	struct ifcvf_hw *vf;
+
+	vf  = vdpa_to_vf(vdpa_dev);
+	adapter = dev_get_drvdata(vdpa_dev->dev.parent);
+
+	if (status == 0) {
+		ifcvf_stop_datapath(adapter);
+		ifcvf_reset_vring(adapter);
+		return;
+	}
+
+	if (status & VIRTIO_CONFIG_S_DRIVER_OK) {
+		if (ifcvf_start_datapath(adapter) < 0)
+			IFCVF_ERR(adapter->pdev,
+				  "Failed to set ifcvf vdpa  status %u\n",
+				  status);
+	}
+
+	ifcvf_set_status(vf, status);
+}
+
+static u16 ifcvf_vdpa_get_vq_num_max(struct vdpa_device *vdpa_dev)
+{
+	return IFCVF_QUEUE_MAX;
+}
+
+static u64 ifcvf_vdpa_get_vq_state(struct vdpa_device *vdpa_dev, u16 qid)
+{
+	struct ifcvf_hw *vf = vdpa_to_vf(vdpa_dev);
+
+	return ifcvf_get_vq_state(vf, qid);
+}
+
+static int ifcvf_vdpa_set_vq_state(struct vdpa_device *vdpa_dev, u16 qid,
+				   u64 num)
+{
+	struct ifcvf_hw *vf = vdpa_to_vf(vdpa_dev);
+
+	return ifcvf_set_vq_state(vf, qid, num);
+}
+
+static void ifcvf_vdpa_set_vq_cb(struct vdpa_device *vdpa_dev, u16 qid,
+				 struct vdpa_callback *cb)
+{
+	struct ifcvf_hw *vf = vdpa_to_vf(vdpa_dev);
+
+	vf->vring[qid].cb = *cb;
+}
+
+static void ifcvf_vdpa_set_vq_ready(struct vdpa_device *vdpa_dev,
+				    u16 qid, bool ready)
+{
+	struct ifcvf_hw *vf = vdpa_to_vf(vdpa_dev);
+
+	vf->vring[qid].ready = ready;
+}
+
+static bool ifcvf_vdpa_get_vq_ready(struct vdpa_device *vdpa_dev, u16 qid)
+{
+	struct ifcvf_hw *vf = vdpa_to_vf(vdpa_dev);
+
+	return vf->vring[qid].ready;
+}
+
+static void ifcvf_vdpa_set_vq_num(struct vdpa_device *vdpa_dev, u16 qid,
+				  u32 num)
+{
+	struct ifcvf_hw *vf = vdpa_to_vf(vdpa_dev);
+
+	vf->vring[qid].size = num;
+}
+
+static int ifcvf_vdpa_set_vq_address(struct vdpa_device *vdpa_dev, u16 qid,
+				     u64 desc_area, u64 driver_area,
+				     u64 device_area)
+{
+	struct ifcvf_hw *vf = vdpa_to_vf(vdpa_dev);
+
+	vf->vring[qid].desc = desc_area;
+	vf->vring[qid].avail = driver_area;
+	vf->vring[qid].used = device_area;
+
+	return 0;
+}
+
+static void ifcvf_vdpa_kick_vq(struct vdpa_device *vdpa_dev, u16 qid)
+{
+	struct ifcvf_hw *vf = vdpa_to_vf(vdpa_dev);
+
+	ifcvf_notify_queue(vf, qid);
+}
+
+static u32 ifcvf_vdpa_get_generation(struct vdpa_device *vdpa_dev)
+{
+	struct ifcvf_hw *vf = vdpa_to_vf(vdpa_dev);
+
+	return ioread8(&vf->common_cfg->config_generation);
+}
+
+static u32 ifcvf_vdpa_get_device_id(struct vdpa_device *vdpa_dev)
+{
+	return VIRTIO_ID_NET;
+}
+
+static u32 ifcvf_vdpa_get_vendor_id(struct vdpa_device *vdpa_dev)
+{
+	return IFCVF_SUBSYS_VENDOR_ID;
+}
+
+static u16 ifcvf_vdpa_get_vq_align(struct vdpa_device *vdpa_dev)
+{
+	return IFCVF_QUEUE_ALIGNMENT;
+}
+
+static void ifcvf_vdpa_get_config(struct vdpa_device *vdpa_dev,
+				  unsigned int offset,
+				  void *buf, unsigned int len)
+{
+	struct ifcvf_hw *vf = vdpa_to_vf(vdpa_dev);
+
+	WARN_ON(offset + len > sizeof(struct virtio_net_config));
+	ifcvf_read_net_config(vf, offset, buf, len);
+}
+
+static void ifcvf_vdpa_set_config(struct vdpa_device *vdpa_dev,
+				  unsigned int offset, const void *buf,
+				  unsigned int len)
+{
+	struct ifcvf_hw *vf = vdpa_to_vf(vdpa_dev);
+
+	WARN_ON(offset + len > sizeof(struct virtio_net_config));
+	ifcvf_write_net_config(vf, offset, buf, len);
+}
+
+static void ifcvf_vdpa_set_config_cb(struct vdpa_device *vdpa_dev,
+				     struct vdpa_callback *cb)
+{
+	/* We don't support config interrupt */
+}
+
+/*
+ * IFCVF currently does't have on-chip IOMMU, so not
+ * implemented set_map()/dma_map()/dma_unmap()
+ */
+static const struct vdpa_config_ops ifc_vdpa_ops = {
+	.get_features	= ifcvf_vdpa_get_features,
+	.set_features	= ifcvf_vdpa_set_features,
+	.get_status	= ifcvf_vdpa_get_status,
+	.set_status	= ifcvf_vdpa_set_status,
+	.get_vq_num_max	= ifcvf_vdpa_get_vq_num_max,
+	.get_vq_state	= ifcvf_vdpa_get_vq_state,
+	.set_vq_state	= ifcvf_vdpa_set_vq_state,
+	.set_vq_cb	= ifcvf_vdpa_set_vq_cb,
+	.set_vq_ready	= ifcvf_vdpa_set_vq_ready,
+	.get_vq_ready	= ifcvf_vdpa_get_vq_ready,
+	.set_vq_num	= ifcvf_vdpa_set_vq_num,
+	.set_vq_address	= ifcvf_vdpa_set_vq_address,
+	.kick_vq	= ifcvf_vdpa_kick_vq,
+	.get_generation	= ifcvf_vdpa_get_generation,
+	.get_device_id	= ifcvf_vdpa_get_device_id,
+	.get_vendor_id	= ifcvf_vdpa_get_vendor_id,
+	.get_vq_align	= ifcvf_vdpa_get_vq_align,
+	.get_config	= ifcvf_vdpa_get_config,
+	.set_config	= ifcvf_vdpa_set_config,
+	.set_config_cb  = ifcvf_vdpa_set_config_cb,
+};
+
+static int ifcvf_request_irq(struct ifcvf_adapter *adapter)
+{
+	struct pci_dev *pdev = adapter->pdev;
+	struct ifcvf_hw *vf = &adapter->vf;
+	int vector, i, ret, irq;
+
+
+	for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++) {
+		snprintf(vf->vring[i].msix_name, 256, "ifcvf[%s]-%d\n",
+			 pci_name(pdev), i);
+		vector = i + IFCVF_MSI_QUEUE_OFF;
+		irq = pci_irq_vector(pdev, vector);
+		ret = devm_request_irq(&pdev->dev, irq,
+				       ifcvf_intr_handler, 0,
+				       vf->vring[i].msix_name,
+				       &vf->vring[i]);
+		if (ret) {
+			IFCVF_ERR(pdev,
+				  "Failed to request irq for vq %d\n", i);
+			return ret;
+		}
+		vf->vring[i].irq = irq;
+	}
+
+	return 0;
+}
+
+static void ifcvf_free_irq_vectors(void *data)
+{
+	pci_free_irq_vectors(data);
+}
+
+static int ifcvf_probe(struct pci_dev *pdev, const struct pci_device_id *id)
+{
+	struct device *dev = &pdev->dev;
+	struct ifcvf_adapter *adapter;
+	struct ifcvf_hw *vf;
+	int ret;
+
+	ret = pcim_enable_device(pdev);
+	if (ret) {
+		IFCVF_ERR(pdev, "Failed to enable device\n");
+		return ret;
+	}
+
+	ret = pcim_iomap_regions(pdev, BIT(0) | BIT(2) | BIT(4),
+				 IFCVF_DRIVER_NAME);
+	if (ret) {
+		IFCVF_ERR(pdev, "Failed to request MMIO region\n");
+		return ret;
+	}
+
+	ret = pci_set_dma_mask(pdev, DMA_BIT_MASK(64));
+	if (ret) {
+		IFCVF_ERR(pdev, "No usable DMA confiugration\n");
+		return ret;
+	}
+
+	ret = pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(64));
+	if (ret) {
+		IFCVF_ERR(pdev,
+			  "No usable coherent DMA confiugration\n");
+		return ret;
+	}
+
+	ret = pci_alloc_irq_vectors(pdev, IFCVF_MAX_INTR,
+				    IFCVF_MAX_INTR, PCI_IRQ_MSIX);
+	if (ret < 0) {
+		IFCVF_ERR(pdev, "Failed to alloc irq vectors\n");
+		return ret;
+	}
+
+	ret = devm_add_action_or_reset(dev, ifcvf_free_irq_vectors, pdev);
+	if (ret) {
+		IFCVF_ERR(pdev,
+			  "Failed for adding devres for freeing irq vectors\n");
+		return ret;
+	}
+
+	adapter = vdpa_alloc_device(struct ifcvf_adapter, vdpa,
+				    dev, &ifc_vdpa_ops);
+	if (adapter == NULL) {
+		IFCVF_ERR(pdev, "Failed to allocate vDPA structure");
+		return -ENOMEM;
+	}
+
+	pci_set_master(pdev);
+	pci_set_drvdata(pdev, adapter);
+
+	vf = &adapter->vf;
+	vf->base = pcim_iomap_table(pdev);
+
+	adapter->pdev = pdev;
+	adapter->vdpa.dma_dev = &pdev->dev;
+
+	ret = ifcvf_request_irq(adapter);
+	if (ret) {
+		IFCVF_ERR(pdev, "Failed to request MSI-X irq\n");
+		goto err;
+	}
+
+	ret = ifcvf_init_hw(vf, pdev);
+	if (ret) {
+		IFCVF_ERR(pdev, "Failed to init IFCVF hw\n");
+		goto err;
+	}
+
+	ret = vdpa_register_device(&adapter->vdpa);
+	if (ret) {
+		IFCVF_ERR(pdev, "Failed to register ifcvf to vdpa bus");
+		goto err;
+	}
+
+	return 0;
+
+err:
+	put_device(&adapter->vdpa.dev);
+	return ret;
+}
+
+static void ifcvf_remove(struct pci_dev *pdev)
+{
+	struct ifcvf_adapter *adapter = pci_get_drvdata(pdev);
+
+	vdpa_unregister_device(&adapter->vdpa);
+}
+
+static struct pci_device_id ifcvf_pci_ids[] = {
+	{ PCI_DEVICE_SUB(IFCVF_VENDOR_ID,
+		IFCVF_DEVICE_ID,
+		IFCVF_SUBSYS_VENDOR_ID,
+		IFCVF_SUBSYS_DEVICE_ID) },
+	{ 0 },
+};
+MODULE_DEVICE_TABLE(pci, ifcvf_pci_ids);
+
+static struct pci_driver ifcvf_driver = {
+	.name     = IFCVF_DRIVER_NAME,
+	.id_table = ifcvf_pci_ids,
+	.probe    = ifcvf_probe,
+	.remove   = ifcvf_remove,
+};
+
+module_pci_driver(ifcvf_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_VERSION(VERSION_STRING);
-- 
2.20.1


^ permalink raw reply	[flat|nested] 38+ messages in thread

* Re: [PATCH V9 0/9] vDPA support
  2020-03-26 14:01 [PATCH V9 0/9] vDPA support Jason Wang
                   ` (8 preceding siblings ...)
  2020-03-26 14:01 ` [PATCH V9 9/9] virtio: Intel IFC VF driver for VDPA Jason Wang
@ 2020-03-29 11:07 ` Michael S. Tsirkin
  9 siblings, 0 replies; 38+ messages in thread
From: Michael S. Tsirkin @ 2020-03-29 11:07 UTC (permalink / raw)
  To: Jason Wang
  Cc: linux-kernel, kvm, virtualization, netdev, jgg, maxime.coquelin,
	cunming.liang, zhihong.wang, rob.miller, xiao.w.wang,
	lingshan.zhu, eperezma, lulu, parav, kevin.tian, stefanha,
	rdunlap, hch, aadam, jiri, shahafs, hanand, mhabets, gdawar,
	saugatm, vmireyno, zhangweining

On Thu, Mar 26, 2020 at 10:01:16PM +0800, Jason Wang wrote:
> Hi all:
> 
> This is an update version of vDPA support in kernel.

OK I put these in my next tree, with an eye towards merging them in 5.7.
Many thanks to everyone who reviewed the patches, especially to Jason
Gunthorpe for reviewing multiple versions of the patches, helping locate
and address the issues.


> vDPA device is a device that uses a datapath which complies with the
> virtio specifications with vendor specific control path. vDPA devices
> can be both physically located on the hardware or emulated by
> software. vDPA hardware devices are usually implemented through PCIE
> with the following types:
> 
> - PF (Physical Function) - A single Physical Function
> - VF (Virtual Function) - Device that supports single root I/O
>   virtualization (SR-IOV). Its Virtual Function (VF) represents a
>   virtualized instance of the device that can be assigned to different
>   partitions
> - ADI (Assignable Device Interface) and its equivalents - With
>   technologies such as Intel Scalable IOV, a virtual device (VDEV)
>   composed by host OS utilizing one or more ADIs. Or its equivalent
>   like SF (Sub function) from Mellanox.
> 
> >From a driver's perspective, depends on how and where the DMA
> translation is done, vDPA devices are split into two types:
> 
> - Platform specific DMA translation - From the driver's perspective,
>   the device can be used on a platform where device access to data in
>   memory is limited and/or translated. An example is a PCIE vDPA whose
>   DMA request was tagged via a bus (e.g PCIE) specific way. DMA
>   translation and protection are done at PCIE bus IOMMU level.
> - Device specific DMA translation - The device implements DMA
>   isolation and protection through its own logic. An example is a vDPA
>   device which uses on-chip IOMMU.
> 
> To hide the differences and complexity of the above types for a vDPA
> device/IOMMU options and in order to present a generic virtio device
> to the upper layer, a device agnostic framework is required.
> 
> This series introduces a software vDPA bus which abstracts the
> common attributes of vDPA device, vDPA bus driver and the
> communication method, the bus operations (vdpa_config_ops) between the
> vDPA device abstraction and the vDPA bus driver. This allows multiple
> types of drivers to be used for vDPA device like the virtio_vdpa and
> vhost_vdpa driver to operate on the bus and allow vDPA device could be
> used by either kernel virtio driver or userspace vhost drivers as:
> 
>    virtio drivers  vhost drivers
>           |             |
>     [virtio bus]   [vhost uAPI]
>           |             |
>    virtio device   vhost device
>    virtio_vdpa drv vhost_vdpa drv
>              \       /
>             [vDPA bus]
>                  |
>             vDPA device
>             hardware drv
>                  |
>             [hardware bus]
>                  |
>             vDPA hardware
> 
> virtio_vdpa driver is a transport implementation for kernel virtio
> drivers on top of vDPA bus operations. An alternative is to refactor
> virtio bus which is sub-optimal since the bus and drivers are designed
> to be use by kernel subsystem, a non-trivial major refactoring is
> needed which may impact a brunches of drivers and devices
> implementation inside the kernel. Using a new transport may grealy
> simply both the design and changes.
> 
> vhost_vdpa driver is a new type of vhost device which allows userspace
> vhost drivers to use vDPA devices via vhost uAPI (with minor
> extension). This help to minimize the changes of existed vhost drivers
> for using vDPA devices.
> 
> With the abstraction of vDPA bus and vDPA bus operations, the
> difference and complexity of the under layer hardware is hidden from
> upper layer. The vDPA bus drivers on top can use a unified
> vdpa_config_ops to control different types of vDPA device.
> 
> Two drivers were implemented with the framework introduced in this
> series:
> 
> - Intel IFC VF driver which depends on the platform IOMMU for DMA
>   translation
> - VDPA simulator which is a software test device with an emulated
>   onchip IOMMU
> 
> Future work:
> 
> - direct doorbell mapping support
> - control virtqueue support
> - dirty page tracking support
> - direct interrupt support
> - management API (devlink)
> 
> Please review.
> 
> Thanks
> 
> Changes from V8:
> 
> - switch to use devres for PCI resoureces of IFCVF (Jason)
> - require the caller of vdap_alloc_device() to use "struct foo"
>   instead of foo (Jason)
> - some tweaks on the IFCVF driver
> 
> Changes from V7:
> 
> - refine kconfig to solve the dependency issues on archs that lacks of
>   CONFIG_VIRTUALIZATION (kbuild)
> 
> Changes from V6:
> 
> - vdpa_alloc_device() will allocate parent strcture (Jason)
> - remove the vdpa core dev info in IFCVF patch (Jason)
> - provide a free method in the vdpa bus operations for drivet to free
>   private data
> - switch to use new layout in vdapsim and IFCVF
> - make IFCVF depends on PCI_MSI (kbuild)
> - some tweaks on the IFCVF driver
> 
> Changes from V5:
> 
> - include Intel IFCVF driver and vhost-vdpa drivers
> - add the platform IOMMU support for vhost-vdpa
> - check the return value of dev_set_name() (Jason)
> - various tweaks and fixes
> 
> Changes from V4:
> 
> - use put_device() instead of kfree when fail to register virtio
>   device (Jason)
> - simplify the error handling when allocating vdpasim device (Jason)
> - don't use device_for_each_child() during module exit (Jason)
> - correct the error checking for vdpa_alloc_device() (Harpreet, Lingshan)
> 
> Changes from V3:
> 
> - various Kconfig fixes (Randy)
> 
> Changes from V2:
> 
> - release idr in the release function for put_device() unwind (Jason)
> - don't panic when fail to register vdpa bus (Jason)
> - use unsigned int instead of int for ida (Jason)
> - fix the wrong commit log in virito_vdpa patches (Jason)
> - make vdpa_sim depends on RUNTIME_TESTING_MENU (Michael)
> - provide a bus release function for vDPA device (Jason)
> - fix the wrong unwind when creating devices for vDPA simulator (Jason)
> - move vDPA simulator to a dedicated directory (Lingshan)
> - cancel the work before release vDPA simulator
> 
> Changes from V1:
> 
> - drop sysfs API, leave the management interface to future development
>   (Michael)
> - introduce incremental DMA ops (dma_map/dma_unmap) (Michael)
> - introduce dma_device and use it instead of parent device for doing
>   IOMMU or DMA from bus driver (Michael, Jason, Ling Shan, Tiwei)
> - accept parent device and dma device when register vdpa device
> - coding style and compile fixes (Randy)
> - using vdpa_xxx instead of xxx_vdpa (Jason)
> - ove vDPA accessors to header and make it static inline (Jason)
> - split vdp_register_device() into two helpers vdpa_init_device() and
>   vdpa_register_device() which allows intermediate step to be done (Jason)
> - warn on invalidate queue state when fail to creating virtqueue (Jason)
> - make to_virtio_vdpa_device() static (Jason)
> - use kmalloc/kfree instead of devres for virtio vdpa device (Jason)
> - avoid using cast in vdpa bus function (Jason)
> - introduce module_vdpa_driver and fix module refcnt (Jason)
> - fix returning freed address in vdapsim coherent DMA addr allocation (Dan)
> - various other fixes and tweaks
> 
> V8: https://lkml.org/lkml/2020/3/25/125
> V7: https://lkml.org/lkml/2020/3/24/21
> V6: https://lkml.org/lkml/2020/3/18/88
> V5: https://lkml.org/lkml/2020/2/26/58
> V4: https://lkml.org/lkml/2020/2/20/59
> V3: https://lkml.org/lkml/2020/2/19/1347
> V2: https://lkml.org/lkml/2020/2/9/275
> V1: https://lkml.org/lkml/2020/1/16/353
> 
> Jason Wang (7):
>   vhost: refine vhost and vringh kconfig
>   vhost: allow per device message handler
>   vhost: factor out IOTLB
>   vringh: IOTLB support
>   vDPA: introduce vDPA bus
>   virtio: introduce a vDPA based transport
>   vdpasim: vDPA device simulator
> 
> Tiwei Bie (1):
>   vhost: introduce vDPA-based backend
> 
> Zhu Lingshan (1):
>   virtio: Intel IFC VF driver for VDPA
> 
>  MAINTAINERS                             |   2 +
>  arch/arm/kvm/Kconfig                    |   2 -
>  arch/arm64/kvm/Kconfig                  |   2 -
>  arch/mips/kvm/Kconfig                   |   2 -
>  arch/powerpc/kvm/Kconfig                |   2 -
>  arch/s390/kvm/Kconfig                   |   4 -
>  arch/x86/kvm/Kconfig                    |   4 -
>  drivers/Kconfig                         |   2 +
>  drivers/misc/mic/Kconfig                |   4 -
>  drivers/net/caif/Kconfig                |   4 -
>  drivers/vhost/Kconfig                   |  42 +-
>  drivers/vhost/Kconfig.vringh            |   6 -
>  drivers/vhost/Makefile                  |   6 +
>  drivers/vhost/iotlb.c                   | 177 +++++
>  drivers/vhost/net.c                     |   5 +-
>  drivers/vhost/scsi.c                    |   2 +-
>  drivers/vhost/vdpa.c                    | 883 ++++++++++++++++++++++++
>  drivers/vhost/vhost.c                   | 233 +++----
>  drivers/vhost/vhost.h                   |  45 +-
>  drivers/vhost/vringh.c                  | 421 ++++++++++-
>  drivers/vhost/vsock.c                   |   2 +-
>  drivers/virtio/Kconfig                  |  15 +
>  drivers/virtio/Makefile                 |   2 +
>  drivers/virtio/vdpa/Kconfig             |  37 +
>  drivers/virtio/vdpa/Makefile            |   4 +
>  drivers/virtio/vdpa/ifcvf/Makefile      |   3 +
>  drivers/virtio/vdpa/ifcvf/ifcvf_base.c  | 389 +++++++++++
>  drivers/virtio/vdpa/ifcvf/ifcvf_base.h  | 118 ++++
>  drivers/virtio/vdpa/ifcvf/ifcvf_main.c  | 435 ++++++++++++
>  drivers/virtio/vdpa/vdpa.c              | 180 +++++
>  drivers/virtio/vdpa/vdpa_sim/Makefile   |   2 +
>  drivers/virtio/vdpa/vdpa_sim/vdpa_sim.c | 629 +++++++++++++++++
>  drivers/virtio/virtio_vdpa.c            | 396 +++++++++++
>  include/linux/vdpa.h                    | 253 +++++++
>  include/linux/vhost_iotlb.h             |  47 ++
>  include/linux/vringh.h                  |  36 +
>  include/uapi/linux/vhost.h              |  24 +
>  include/uapi/linux/vhost_types.h        |   8 +
>  38 files changed, 4180 insertions(+), 248 deletions(-)
>  delete mode 100644 drivers/vhost/Kconfig.vringh
>  create mode 100644 drivers/vhost/iotlb.c
>  create mode 100644 drivers/vhost/vdpa.c
>  create mode 100644 drivers/virtio/vdpa/Kconfig
>  create mode 100644 drivers/virtio/vdpa/Makefile
>  create mode 100644 drivers/virtio/vdpa/ifcvf/Makefile
>  create mode 100644 drivers/virtio/vdpa/ifcvf/ifcvf_base.c
>  create mode 100644 drivers/virtio/vdpa/ifcvf/ifcvf_base.h
>  create mode 100644 drivers/virtio/vdpa/ifcvf/ifcvf_main.c
>  create mode 100644 drivers/virtio/vdpa/vdpa.c
>  create mode 100644 drivers/virtio/vdpa/vdpa_sim/Makefile
>  create mode 100644 drivers/virtio/vdpa/vdpa_sim/vdpa_sim.c
>  create mode 100644 drivers/virtio/virtio_vdpa.c
>  create mode 100644 include/linux/vdpa.h
>  create mode 100644 include/linux/vhost_iotlb.h
> 
> -- 
> 2.20.1


^ permalink raw reply	[flat|nested] 38+ messages in thread

* Re: [PATCH V9 1/9] vhost: refine vhost and vringh kconfig
  2020-03-26 14:01 ` [PATCH V9 1/9] vhost: refine vhost and vringh kconfig Jason Wang
@ 2020-04-01 11:21   ` Christian Borntraeger
  2020-04-01 12:50     ` Jason Wang
  2020-04-01 13:22   ` Michael S. Tsirkin
  1 sibling, 1 reply; 38+ messages in thread
From: Christian Borntraeger @ 2020-04-01 11:21 UTC (permalink / raw)
  To: Jason Wang, mst, linux-kernel, kvm, virtualization, netdev
  Cc: jgg, maxime.coquelin, cunming.liang, zhihong.wang, rob.miller,
	xiao.w.wang, lingshan.zhu, eperezma, lulu, parav, kevin.tian,
	stefanha, rdunlap, hch, aadam, jiri, shahafs, hanand, mhabets,
	gdawar, saugatm, vmireyno, zhangweining


On 26.03.20 15:01, Jason Wang wrote:
> Currently, CONFIG_VHOST depends on CONFIG_VIRTUALIZATION. But vhost is
> not necessarily for VM since it's a generic userspace and kernel
> communication protocol. Such dependency may prevent archs without
> virtualization support from using vhost.
> 
> To solve this, a dedicated vhost menu is created under drivers so
> CONIFG_VHOST can be decoupled out of CONFIG_VIRTUALIZATION.


FWIW, this now results in vhost not being build with defconfig kernels (in todays
linux-next). 

> 
> While at it, also squash Kconfig.vringh into vhost Kconfig file. This
> avoids the trick of conditional inclusion from VOP or CAIF. Then it
> will be easier to introduce new vringh users and common dependency for
> both vringh and vhost.
> 
> Signed-off-by: Jason Wang <jasowang@redhat.com>
> ---
>  arch/arm/kvm/Kconfig         |  2 --
>  arch/arm64/kvm/Kconfig       |  2 --
>  arch/mips/kvm/Kconfig        |  2 --
>  arch/powerpc/kvm/Kconfig     |  2 --
>  arch/s390/kvm/Kconfig        |  4 ----
>  arch/x86/kvm/Kconfig         |  4 ----
>  drivers/Kconfig              |  2 ++
>  drivers/misc/mic/Kconfig     |  4 ----
>  drivers/net/caif/Kconfig     |  4 ----
>  drivers/vhost/Kconfig        | 23 ++++++++++++++---------
>  drivers/vhost/Kconfig.vringh |  6 ------
>  11 files changed, 16 insertions(+), 39 deletions(-)
>  delete mode 100644 drivers/vhost/Kconfig.vringh
> 
> diff --git a/arch/arm/kvm/Kconfig b/arch/arm/kvm/Kconfig
> index f591026347a5..be97393761bf 100644
> --- a/arch/arm/kvm/Kconfig
> +++ b/arch/arm/kvm/Kconfig
> @@ -54,6 +54,4 @@ config KVM_ARM_HOST
>  	---help---
>  	  Provides host support for ARM processors.
>  
> -source "drivers/vhost/Kconfig"
> -
>  endif # VIRTUALIZATION
> diff --git a/arch/arm64/kvm/Kconfig b/arch/arm64/kvm/Kconfig
> index a475c68cbfec..449386d76441 100644
> --- a/arch/arm64/kvm/Kconfig
> +++ b/arch/arm64/kvm/Kconfig
> @@ -64,6 +64,4 @@ config KVM_ARM_PMU
>  config KVM_INDIRECT_VECTORS
>         def_bool KVM && (HARDEN_BRANCH_PREDICTOR || HARDEN_EL2_VECTORS)
>  
> -source "drivers/vhost/Kconfig"
> -
>  endif # VIRTUALIZATION
> diff --git a/arch/mips/kvm/Kconfig b/arch/mips/kvm/Kconfig
> index eac25aef21e0..b91d145aa2d5 100644
> --- a/arch/mips/kvm/Kconfig
> +++ b/arch/mips/kvm/Kconfig
> @@ -72,6 +72,4 @@ config KVM_MIPS_DEBUG_COP0_COUNTERS
>  
>  	  If unsure, say N.
>  
> -source "drivers/vhost/Kconfig"
> -
>  endif # VIRTUALIZATION
> diff --git a/arch/powerpc/kvm/Kconfig b/arch/powerpc/kvm/Kconfig
> index 711fca9bc6f0..12885eda324e 100644
> --- a/arch/powerpc/kvm/Kconfig
> +++ b/arch/powerpc/kvm/Kconfig
> @@ -204,6 +204,4 @@ config KVM_XIVE
>  	default y
>  	depends on KVM_XICS && PPC_XIVE_NATIVE && KVM_BOOK3S_HV_POSSIBLE
>  
> -source "drivers/vhost/Kconfig"
> -
>  endif # VIRTUALIZATION
> diff --git a/arch/s390/kvm/Kconfig b/arch/s390/kvm/Kconfig
> index d3db3d7ed077..def3b60f1fe8 100644
> --- a/arch/s390/kvm/Kconfig
> +++ b/arch/s390/kvm/Kconfig
> @@ -55,8 +55,4 @@ config KVM_S390_UCONTROL
>  
>  	  If unsure, say N.
>  
> -# OK, it's a little counter-intuitive to do this, but it puts it neatly under
> -# the virtualization menu.
> -source "drivers/vhost/Kconfig"
> -
>  endif # VIRTUALIZATION
> diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig
> index 991019d5eee1..0dfe70e17af9 100644
> --- a/arch/x86/kvm/Kconfig
> +++ b/arch/x86/kvm/Kconfig
> @@ -94,8 +94,4 @@ config KVM_MMU_AUDIT
>  	 This option adds a R/W kVM module parameter 'mmu_audit', which allows
>  	 auditing of KVM MMU events at runtime.
>  
> -# OK, it's a little counter-intuitive to do this, but it puts it neatly under
> -# the virtualization menu.
> -source "drivers/vhost/Kconfig"
> -
>  endif # VIRTUALIZATION
> diff --git a/drivers/Kconfig b/drivers/Kconfig
> index 8befa53f43be..7a6d8b2b68b4 100644
> --- a/drivers/Kconfig
> +++ b/drivers/Kconfig
> @@ -138,6 +138,8 @@ source "drivers/virt/Kconfig"
>  
>  source "drivers/virtio/Kconfig"
>  
> +source "drivers/vhost/Kconfig"
> +
>  source "drivers/hv/Kconfig"
>  
>  source "drivers/xen/Kconfig"
> diff --git a/drivers/misc/mic/Kconfig b/drivers/misc/mic/Kconfig
> index b6841ba6d922..8f201d019f5a 100644
> --- a/drivers/misc/mic/Kconfig
> +++ b/drivers/misc/mic/Kconfig
> @@ -133,8 +133,4 @@ config VOP
>  	  OS and tools for MIC to use with this driver are available from
>  	  <http://software.intel.com/en-us/mic-developer>.
>  
> -if VOP
> -source "drivers/vhost/Kconfig.vringh"
> -endif
> -
>  endmenu
> diff --git a/drivers/net/caif/Kconfig b/drivers/net/caif/Kconfig
> index e74e2bb61236..9db0570c5beb 100644
> --- a/drivers/net/caif/Kconfig
> +++ b/drivers/net/caif/Kconfig
> @@ -58,8 +58,4 @@ config CAIF_VIRTIO
>  	---help---
>  	  The CAIF driver for CAIF over Virtio.
>  
> -if CAIF_VIRTIO
> -source "drivers/vhost/Kconfig.vringh"
> -endif
> -
>  endif # CAIF_DRIVERS
> diff --git a/drivers/vhost/Kconfig b/drivers/vhost/Kconfig
> index 3d03ccbd1adc..4aef10a54cd1 100644
> --- a/drivers/vhost/Kconfig
> +++ b/drivers/vhost/Kconfig
> @@ -1,8 +1,20 @@
>  # SPDX-License-Identifier: GPL-2.0-only
> +config VHOST_RING
> +	tristate
> +	help
> +	  This option is selected by any driver which needs to access
> +	  the host side of a virtio ring.
> +
> +menuconfig VHOST
> +	tristate "Host kernel accelerator for virtio (VHOST)"
> +	help
> +	  This option is selected by any driver which needs to access
> +	  the core of vhost.
> +if VHOST
> +
>  config VHOST_NET
>  	tristate "Host kernel accelerator for virtio net"
>  	depends on NET && EVENTFD && (TUN || !TUN) && (TAP || !TAP)
> -	select VHOST
>  	---help---
>  	  This kernel module can be loaded in host kernel to accelerate
>  	  guest networking with virtio_net. Not to be confused with virtio_net
> @@ -14,7 +26,6 @@ config VHOST_NET
>  config VHOST_SCSI
>  	tristate "VHOST_SCSI TCM fabric driver"
>  	depends on TARGET_CORE && EVENTFD
> -	select VHOST
>  	default n
>  	---help---
>  	Say M here to enable the vhost_scsi TCM fabric module
> @@ -24,7 +35,6 @@ config VHOST_VSOCK
>  	tristate "vhost virtio-vsock driver"
>  	depends on VSOCKETS && EVENTFD
>  	select VIRTIO_VSOCKETS_COMMON
> -	select VHOST
>  	default n
>  	---help---
>  	This kernel module can be loaded in the host kernel to provide AF_VSOCK
> @@ -34,12 +44,6 @@ config VHOST_VSOCK
>  	To compile this driver as a module, choose M here: the module will be called
>  	vhost_vsock.
>  
> -config VHOST
> -	tristate
> -	---help---
> -	  This option is selected by any driver which needs to access
> -	  the core of vhost.
> -
>  config VHOST_CROSS_ENDIAN_LEGACY
>  	bool "Cross-endian support for vhost"
>  	default n
> @@ -54,3 +58,4 @@ config VHOST_CROSS_ENDIAN_LEGACY
>  	  adds some overhead, it is disabled by default.
>  
>  	  If unsure, say "N".
> +endif
> diff --git a/drivers/vhost/Kconfig.vringh b/drivers/vhost/Kconfig.vringh
> deleted file mode 100644
> index c1fe36a9b8d4..000000000000
> --- a/drivers/vhost/Kconfig.vringh
> +++ /dev/null
> @@ -1,6 +0,0 @@
> -# SPDX-License-Identifier: GPL-2.0-only
> -config VHOST_RING
> -	tristate
> -	---help---
> -	  This option is selected by any driver which needs to access
> -	  the host side of a virtio ring.
> 


^ permalink raw reply	[flat|nested] 38+ messages in thread

* Re: [PATCH V9 1/9] vhost: refine vhost and vringh kconfig
  2020-04-01 11:21   ` Christian Borntraeger
@ 2020-04-01 12:50     ` Jason Wang
  2020-04-01 12:56       ` Christian Borntraeger
  0 siblings, 1 reply; 38+ messages in thread
From: Jason Wang @ 2020-04-01 12:50 UTC (permalink / raw)
  To: Christian Borntraeger, mst, linux-kernel, kvm, virtualization, netdev
  Cc: jgg, maxime.coquelin, cunming.liang, zhihong.wang, rob.miller,
	xiao.w.wang, lingshan.zhu, eperezma, lulu, parav, kevin.tian,
	stefanha, rdunlap, hch, aadam, jiri, shahafs, hanand, mhabets,
	gdawar, saugatm, vmireyno, zhangweining


On 2020/4/1 下午7:21, Christian Borntraeger wrote:
> On 26.03.20 15:01, Jason Wang wrote:
>> Currently, CONFIG_VHOST depends on CONFIG_VIRTUALIZATION. But vhost is
>> not necessarily for VM since it's a generic userspace and kernel
>> communication protocol. Such dependency may prevent archs without
>> virtualization support from using vhost.
>>
>> To solve this, a dedicated vhost menu is created under drivers so
>> CONIFG_VHOST can be decoupled out of CONFIG_VIRTUALIZATION.
> FWIW, this now results in vhost not being build with defconfig kernels (in todays
> linux-next).
>

Hi Christian:

Did you meet it even with this 
commit https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?id=a4be40cbcedba9b5b714f3c95182e8a45176e42d?

If yes, what's your build config looks like?

Thanks


^ permalink raw reply	[flat|nested] 38+ messages in thread

* Re: [PATCH V9 1/9] vhost: refine vhost and vringh kconfig
  2020-04-01 12:50     ` Jason Wang
@ 2020-04-01 12:56       ` Christian Borntraeger
  2020-04-01 13:02         ` Christian Borntraeger
  0 siblings, 1 reply; 38+ messages in thread
From: Christian Borntraeger @ 2020-04-01 12:56 UTC (permalink / raw)
  To: Jason Wang, mst, linux-kernel, kvm, virtualization, netdev
  Cc: jgg, maxime.coquelin, cunming.liang, zhihong.wang, rob.miller,
	xiao.w.wang, lingshan.zhu, eperezma, lulu, parav, kevin.tian,
	stefanha, rdunlap, hch, aadam, jiri, shahafs, hanand, mhabets,
	gdawar, saugatm, vmireyno, zhangweining


On 01.04.20 14:50, Jason Wang wrote:
> 
> On 2020/4/1 下午7:21, Christian Borntraeger wrote:
>> On 26.03.20 15:01, Jason Wang wrote:
>>> Currently, CONFIG_VHOST depends on CONFIG_VIRTUALIZATION. But vhost is
>>> not necessarily for VM since it's a generic userspace and kernel
>>> communication protocol. Such dependency may prevent archs without
>>> virtualization support from using vhost.
>>>
>>> To solve this, a dedicated vhost menu is created under drivers so
>>> CONIFG_VHOST can be decoupled out of CONFIG_VIRTUALIZATION.
>> FWIW, this now results in vhost not being build with defconfig kernels (in todays
>> linux-next).
>>
> 
> Hi Christian:
> 
> Did you meet it even with this commit https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?id=a4be40cbcedba9b5b714f3c95182e8a45176e42d?

I simply used linux-next. The defconfig does NOT contain CONFIG_VHOST and therefore CONFIG_VHOST_NET and friends
can not be selected.

$ git checkout next-20200401
$ make defconfig
  HOSTCC  scripts/basic/fixdep
  HOSTCC  scripts/kconfig/conf.o
  HOSTCC  scripts/kconfig/confdata.o
  HOSTCC  scripts/kconfig/expr.o
  LEX     scripts/kconfig/lexer.lex.c
  YACC    scripts/kconfig/parser.tab.[ch]
  HOSTCC  scripts/kconfig/lexer.lex.o
  HOSTCC  scripts/kconfig/parser.tab.o
  HOSTCC  scripts/kconfig/preprocess.o
  HOSTCC  scripts/kconfig/symbol.o
  HOSTCC  scripts/kconfig/util.o
  HOSTLD  scripts/kconfig/conf
*** Default configuration is based on 'x86_64_defconfig'
#
# configuration written to .config
#

$ grep VHOST .config
# CONFIG_VHOST is not set

 
> If yes, what's your build config looks like?
> 
> Thanks
> 


^ permalink raw reply	[flat|nested] 38+ messages in thread

* Re: [PATCH V9 1/9] vhost: refine vhost and vringh kconfig
  2020-04-01 12:56       ` Christian Borntraeger
@ 2020-04-01 13:02         ` Christian Borntraeger
  2020-04-01 14:01           ` Michael S. Tsirkin
  2020-04-01 14:13           ` Jason Wang
  0 siblings, 2 replies; 38+ messages in thread
From: Christian Borntraeger @ 2020-04-01 13:02 UTC (permalink / raw)
  To: Jason Wang, mst, linux-kernel, kvm, virtualization, netdev
  Cc: jgg, maxime.coquelin, cunming.liang, zhihong.wang, rob.miller,
	xiao.w.wang, lingshan.zhu, eperezma, lulu, parav, kevin.tian,
	stefanha, rdunlap, hch, aadam, jiri, shahafs, hanand, mhabets,
	gdawar, saugatm, vmireyno, zhangweining



On 01.04.20 14:56, Christian Borntraeger wrote:
> 
> On 01.04.20 14:50, Jason Wang wrote:
>>
>> On 2020/4/1 下午7:21, Christian Borntraeger wrote:
>>> On 26.03.20 15:01, Jason Wang wrote:
>>>> Currently, CONFIG_VHOST depends on CONFIG_VIRTUALIZATION. But vhost is
>>>> not necessarily for VM since it's a generic userspace and kernel
>>>> communication protocol. Such dependency may prevent archs without
>>>> virtualization support from using vhost.
>>>>
>>>> To solve this, a dedicated vhost menu is created under drivers so
>>>> CONIFG_VHOST can be decoupled out of CONFIG_VIRTUALIZATION.
>>> FWIW, this now results in vhost not being build with defconfig kernels (in todays
>>> linux-next).
>>>
>>
>> Hi Christian:
>>
>> Did you meet it even with this commit https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?id=a4be40cbcedba9b5b714f3c95182e8a45176e42d?
> 
> I simply used linux-next. The defconfig does NOT contain CONFIG_VHOST and therefore CONFIG_VHOST_NET and friends
> can not be selected.
> 
> $ git checkout next-20200401
> $ make defconfig
>   HOSTCC  scripts/basic/fixdep
>   HOSTCC  scripts/kconfig/conf.o
>   HOSTCC  scripts/kconfig/confdata.o
>   HOSTCC  scripts/kconfig/expr.o
>   LEX     scripts/kconfig/lexer.lex.c
>   YACC    scripts/kconfig/parser.tab.[ch]
>   HOSTCC  scripts/kconfig/lexer.lex.o
>   HOSTCC  scripts/kconfig/parser.tab.o
>   HOSTCC  scripts/kconfig/preprocess.o
>   HOSTCC  scripts/kconfig/symbol.o
>   HOSTCC  scripts/kconfig/util.o
>   HOSTLD  scripts/kconfig/conf
> *** Default configuration is based on 'x86_64_defconfig'
> #
> # configuration written to .config
> #
> 
> $ grep VHOST .config
> # CONFIG_VHOST is not set
> 
>  
>> If yes, what's your build config looks like?
>>
>> Thanks

This was x86. Not sure if that did work before.
On s390 this is definitely a regression as the defconfig files 
for s390 do select VHOST_NET

grep VHOST arch/s390/configs/*
arch/s390/configs/debug_defconfig:CONFIG_VHOST_NET=m
arch/s390/configs/debug_defconfig:CONFIG_VHOST_VSOCK=m
arch/s390/configs/defconfig:CONFIG_VHOST_NET=m
arch/s390/configs/defconfig:CONFIG_VHOST_VSOCK=m

and this worked with 5.6, but does not work with next. Just adding
CONFIG_VHOST=m to the defconfig solves the issue, something like

---
 arch/s390/configs/debug_defconfig | 5 +++--
 arch/s390/configs/defconfig       | 5 +++--
 2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/arch/s390/configs/debug_defconfig b/arch/s390/configs/debug_defconfig
index 46038bc58c9e..0b83274341ce 100644
--- a/arch/s390/configs/debug_defconfig
+++ b/arch/s390/configs/debug_defconfig
@@ -57,8 +57,6 @@ CONFIG_PROTECTED_VIRTUALIZATION_GUEST=y
 CONFIG_CMM=m
 CONFIG_APPLDATA_BASE=y
 CONFIG_KVM=m
-CONFIG_VHOST_NET=m
-CONFIG_VHOST_VSOCK=m
 CONFIG_OPROFILE=m
 CONFIG_KPROBES=y
 CONFIG_JUMP_LABEL=y
@@ -561,6 +559,9 @@ CONFIG_VFIO_MDEV_DEVICE=m
 CONFIG_VIRTIO_PCI=m
 CONFIG_VIRTIO_BALLOON=m
 CONFIG_VIRTIO_INPUT=y
+CONFIG_VHOST=m
+CONFIG_VHOST_NET=m
+CONFIG_VHOST_VSOCK=m
 CONFIG_S390_CCW_IOMMU=y
 CONFIG_S390_AP_IOMMU=y
 CONFIG_EXT4_FS=y
diff --git a/arch/s390/configs/defconfig b/arch/s390/configs/defconfig
index 7cd0648c1f4e..39e69c4e8cf7 100644
--- a/arch/s390/configs/defconfig
+++ b/arch/s390/configs/defconfig
@@ -57,8 +57,6 @@ CONFIG_PROTECTED_VIRTUALIZATION_GUEST=y
 CONFIG_CMM=m
 CONFIG_APPLDATA_BASE=y
 CONFIG_KVM=m
-CONFIG_VHOST_NET=m
-CONFIG_VHOST_VSOCK=m
 CONFIG_OPROFILE=m
 CONFIG_KPROBES=y
 CONFIG_JUMP_LABEL=y
@@ -557,6 +555,9 @@ CONFIG_VFIO_MDEV_DEVICE=m
 CONFIG_VIRTIO_PCI=m
 CONFIG_VIRTIO_BALLOON=m
 CONFIG_VIRTIO_INPUT=y
+CONFIG_VHOST=m
+CONFIG_VHOST_NET=m
+CONFIG_VHOST_VSOCK=m
 CONFIG_S390_CCW_IOMMU=y
 CONFIG_S390_AP_IOMMU=y
 CONFIG_EXT4_FS=y
-- 
2.25.1


^ permalink raw reply	[flat|nested] 38+ messages in thread

* Re: [PATCH V9 1/9] vhost: refine vhost and vringh kconfig
  2020-03-26 14:01 ` [PATCH V9 1/9] vhost: refine vhost and vringh kconfig Jason Wang
  2020-04-01 11:21   ` Christian Borntraeger
@ 2020-04-01 13:22   ` Michael S. Tsirkin
  2020-04-01 14:08     ` Jason Wang
  1 sibling, 1 reply; 38+ messages in thread
From: Michael S. Tsirkin @ 2020-04-01 13:22 UTC (permalink / raw)
  To: Jason Wang
  Cc: linux-kernel, kvm, virtualization, netdev, jgg, maxime.coquelin,
	cunming.liang, zhihong.wang, rob.miller, xiao.w.wang,
	lingshan.zhu, eperezma, lulu, parav, kevin.tian, stefanha,
	rdunlap, hch, aadam, jiri, shahafs, hanand, mhabets, gdawar,
	saugatm, vmireyno, zhangweining

On Thu, Mar 26, 2020 at 10:01:17PM +0800, Jason Wang wrote:
> Currently, CONFIG_VHOST depends on CONFIG_VIRTUALIZATION. But vhost is
> not necessarily for VM since it's a generic userspace and kernel
> communication protocol. Such dependency may prevent archs without
> virtualization support from using vhost.
> 
> To solve this, a dedicated vhost menu is created under drivers so
> CONIFG_VHOST can be decoupled out of CONFIG_VIRTUALIZATION.
> 
> While at it, also squash Kconfig.vringh into vhost Kconfig file. This
> avoids the trick of conditional inclusion from VOP or CAIF. Then it
> will be easier to introduce new vringh users and common dependency for
> both vringh and vhost.
> 
> Signed-off-by: Jason Wang <jasowang@redhat.com>

Is this just so we can drop the dependency on CONFIG_VIRTUALIZATION?
If yes what happens if we drop this patch?
Given the impact it had I'd like to defer it till next release if
possible.


> ---
>  arch/arm/kvm/Kconfig         |  2 --
>  arch/arm64/kvm/Kconfig       |  2 --
>  arch/mips/kvm/Kconfig        |  2 --
>  arch/powerpc/kvm/Kconfig     |  2 --
>  arch/s390/kvm/Kconfig        |  4 ----
>  arch/x86/kvm/Kconfig         |  4 ----
>  drivers/Kconfig              |  2 ++
>  drivers/misc/mic/Kconfig     |  4 ----
>  drivers/net/caif/Kconfig     |  4 ----
>  drivers/vhost/Kconfig        | 23 ++++++++++++++---------
>  drivers/vhost/Kconfig.vringh |  6 ------
>  11 files changed, 16 insertions(+), 39 deletions(-)
>  delete mode 100644 drivers/vhost/Kconfig.vringh
> 
> diff --git a/arch/arm/kvm/Kconfig b/arch/arm/kvm/Kconfig
> index f591026347a5..be97393761bf 100644
> --- a/arch/arm/kvm/Kconfig
> +++ b/arch/arm/kvm/Kconfig
> @@ -54,6 +54,4 @@ config KVM_ARM_HOST
>  	---help---
>  	  Provides host support for ARM processors.
>  
> -source "drivers/vhost/Kconfig"
> -
>  endif # VIRTUALIZATION
> diff --git a/arch/arm64/kvm/Kconfig b/arch/arm64/kvm/Kconfig
> index a475c68cbfec..449386d76441 100644
> --- a/arch/arm64/kvm/Kconfig
> +++ b/arch/arm64/kvm/Kconfig
> @@ -64,6 +64,4 @@ config KVM_ARM_PMU
>  config KVM_INDIRECT_VECTORS
>         def_bool KVM && (HARDEN_BRANCH_PREDICTOR || HARDEN_EL2_VECTORS)
>  
> -source "drivers/vhost/Kconfig"
> -
>  endif # VIRTUALIZATION
> diff --git a/arch/mips/kvm/Kconfig b/arch/mips/kvm/Kconfig
> index eac25aef21e0..b91d145aa2d5 100644
> --- a/arch/mips/kvm/Kconfig
> +++ b/arch/mips/kvm/Kconfig
> @@ -72,6 +72,4 @@ config KVM_MIPS_DEBUG_COP0_COUNTERS
>  
>  	  If unsure, say N.
>  
> -source "drivers/vhost/Kconfig"
> -
>  endif # VIRTUALIZATION
> diff --git a/arch/powerpc/kvm/Kconfig b/arch/powerpc/kvm/Kconfig
> index 711fca9bc6f0..12885eda324e 100644
> --- a/arch/powerpc/kvm/Kconfig
> +++ b/arch/powerpc/kvm/Kconfig
> @@ -204,6 +204,4 @@ config KVM_XIVE
>  	default y
>  	depends on KVM_XICS && PPC_XIVE_NATIVE && KVM_BOOK3S_HV_POSSIBLE
>  
> -source "drivers/vhost/Kconfig"
> -
>  endif # VIRTUALIZATION
> diff --git a/arch/s390/kvm/Kconfig b/arch/s390/kvm/Kconfig
> index d3db3d7ed077..def3b60f1fe8 100644
> --- a/arch/s390/kvm/Kconfig
> +++ b/arch/s390/kvm/Kconfig
> @@ -55,8 +55,4 @@ config KVM_S390_UCONTROL
>  
>  	  If unsure, say N.
>  
> -# OK, it's a little counter-intuitive to do this, but it puts it neatly under
> -# the virtualization menu.
> -source "drivers/vhost/Kconfig"
> -
>  endif # VIRTUALIZATION
> diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig
> index 991019d5eee1..0dfe70e17af9 100644
> --- a/arch/x86/kvm/Kconfig
> +++ b/arch/x86/kvm/Kconfig
> @@ -94,8 +94,4 @@ config KVM_MMU_AUDIT
>  	 This option adds a R/W kVM module parameter 'mmu_audit', which allows
>  	 auditing of KVM MMU events at runtime.
>  
> -# OK, it's a little counter-intuitive to do this, but it puts it neatly under
> -# the virtualization menu.
> -source "drivers/vhost/Kconfig"
> -
>  endif # VIRTUALIZATION
> diff --git a/drivers/Kconfig b/drivers/Kconfig
> index 8befa53f43be..7a6d8b2b68b4 100644
> --- a/drivers/Kconfig
> +++ b/drivers/Kconfig
> @@ -138,6 +138,8 @@ source "drivers/virt/Kconfig"
>  
>  source "drivers/virtio/Kconfig"
>  
> +source "drivers/vhost/Kconfig"
> +
>  source "drivers/hv/Kconfig"
>  
>  source "drivers/xen/Kconfig"
> diff --git a/drivers/misc/mic/Kconfig b/drivers/misc/mic/Kconfig
> index b6841ba6d922..8f201d019f5a 100644
> --- a/drivers/misc/mic/Kconfig
> +++ b/drivers/misc/mic/Kconfig
> @@ -133,8 +133,4 @@ config VOP
>  	  OS and tools for MIC to use with this driver are available from
>  	  <http://software.intel.com/en-us/mic-developer>.
>  
> -if VOP
> -source "drivers/vhost/Kconfig.vringh"
> -endif
> -
>  endmenu
> diff --git a/drivers/net/caif/Kconfig b/drivers/net/caif/Kconfig
> index e74e2bb61236..9db0570c5beb 100644
> --- a/drivers/net/caif/Kconfig
> +++ b/drivers/net/caif/Kconfig
> @@ -58,8 +58,4 @@ config CAIF_VIRTIO
>  	---help---
>  	  The CAIF driver for CAIF over Virtio.
>  
> -if CAIF_VIRTIO
> -source "drivers/vhost/Kconfig.vringh"
> -endif
> -
>  endif # CAIF_DRIVERS
> diff --git a/drivers/vhost/Kconfig b/drivers/vhost/Kconfig
> index 3d03ccbd1adc..4aef10a54cd1 100644
> --- a/drivers/vhost/Kconfig
> +++ b/drivers/vhost/Kconfig
> @@ -1,8 +1,20 @@
>  # SPDX-License-Identifier: GPL-2.0-only
> +config VHOST_RING
> +	tristate
> +	help
> +	  This option is selected by any driver which needs to access
> +	  the host side of a virtio ring.
> +
> +menuconfig VHOST
> +	tristate "Host kernel accelerator for virtio (VHOST)"
> +	help
> +	  This option is selected by any driver which needs to access
> +	  the core of vhost.
> +if VHOST
> +

The description here is wrong, isn't it?
VHOST and VHOST_RING are no longer selected, right?


>  config VHOST_NET
>  	tristate "Host kernel accelerator for virtio net"
>  	depends on NET && EVENTFD && (TUN || !TUN) && (TAP || !TAP)
> -	select VHOST
>  	---help---
>  	  This kernel module can be loaded in host kernel to accelerate
>  	  guest networking with virtio_net. Not to be confused with virtio_net
> @@ -14,7 +26,6 @@ config VHOST_NET
>  config VHOST_SCSI
>  	tristate "VHOST_SCSI TCM fabric driver"
>  	depends on TARGET_CORE && EVENTFD
> -	select VHOST
>  	default n
>  	---help---
>  	Say M here to enable the vhost_scsi TCM fabric module
> @@ -24,7 +35,6 @@ config VHOST_VSOCK
>  	tristate "vhost virtio-vsock driver"
>  	depends on VSOCKETS && EVENTFD
>  	select VIRTIO_VSOCKETS_COMMON
> -	select VHOST
>  	default n
>  	---help---
>  	This kernel module can be loaded in the host kernel to provide AF_VSOCK
> @@ -34,12 +44,6 @@ config VHOST_VSOCK
>  	To compile this driver as a module, choose M here: the module will be called
>  	vhost_vsock.
>  
> -config VHOST
> -	tristate
> -	---help---
> -	  This option is selected by any driver which needs to access
> -	  the core of vhost.
> -
>  config VHOST_CROSS_ENDIAN_LEGACY
>  	bool "Cross-endian support for vhost"
>  	default n
> @@ -54,3 +58,4 @@ config VHOST_CROSS_ENDIAN_LEGACY
>  	  adds some overhead, it is disabled by default.
>  
>  	  If unsure, say "N".
> +endif
> diff --git a/drivers/vhost/Kconfig.vringh b/drivers/vhost/Kconfig.vringh
> deleted file mode 100644
> index c1fe36a9b8d4..000000000000
> --- a/drivers/vhost/Kconfig.vringh
> +++ /dev/null
> @@ -1,6 +0,0 @@
> -# SPDX-License-Identifier: GPL-2.0-only
> -config VHOST_RING
> -	tristate
> -	---help---
> -	  This option is selected by any driver which needs to access
> -	  the host side of a virtio ring.
> -- 
> 2.20.1


^ permalink raw reply	[flat|nested] 38+ messages in thread

* Re: [PATCH V9 1/9] vhost: refine vhost and vringh kconfig
  2020-04-01 13:02         ` Christian Borntraeger
@ 2020-04-01 14:01           ` Michael S. Tsirkin
  2020-04-01 14:13           ` Jason Wang
  1 sibling, 0 replies; 38+ messages in thread
From: Michael S. Tsirkin @ 2020-04-01 14:01 UTC (permalink / raw)
  To: Christian Borntraeger
  Cc: Jason Wang, linux-kernel, kvm, virtualization, netdev, jgg,
	maxime.coquelin, cunming.liang, zhihong.wang, rob.miller,
	xiao.w.wang, lingshan.zhu, eperezma, lulu, parav, kevin.tian,
	stefanha, rdunlap, hch, aadam, jiri, shahafs, hanand, mhabets,
	gdawar, saugatm, vmireyno, zhangweining

On Wed, Apr 01, 2020 at 03:02:00PM +0200, Christian Borntraeger wrote:
> 
> 
> On 01.04.20 14:56, Christian Borntraeger wrote:
> > 
> > On 01.04.20 14:50, Jason Wang wrote:
> >>
> >> On 2020/4/1 下午7:21, Christian Borntraeger wrote:
> >>> On 26.03.20 15:01, Jason Wang wrote:
> >>>> Currently, CONFIG_VHOST depends on CONFIG_VIRTUALIZATION. But vhost is
> >>>> not necessarily for VM since it's a generic userspace and kernel
> >>>> communication protocol. Such dependency may prevent archs without
> >>>> virtualization support from using vhost.
> >>>>
> >>>> To solve this, a dedicated vhost menu is created under drivers so
> >>>> CONIFG_VHOST can be decoupled out of CONFIG_VIRTUALIZATION.
> >>> FWIW, this now results in vhost not being build with defconfig kernels (in todays
> >>> linux-next).
> >>>
> >>
> >> Hi Christian:
> >>
> >> Did you meet it even with this commit https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?id=a4be40cbcedba9b5b714f3c95182e8a45176e42d?
> > 
> > I simply used linux-next. The defconfig does NOT contain CONFIG_VHOST and therefore CONFIG_VHOST_NET and friends
> > can not be selected.
> > 
> > $ git checkout next-20200401
> > $ make defconfig
> >   HOSTCC  scripts/basic/fixdep
> >   HOSTCC  scripts/kconfig/conf.o
> >   HOSTCC  scripts/kconfig/confdata.o
> >   HOSTCC  scripts/kconfig/expr.o
> >   LEX     scripts/kconfig/lexer.lex.c
> >   YACC    scripts/kconfig/parser.tab.[ch]
> >   HOSTCC  scripts/kconfig/lexer.lex.o
> >   HOSTCC  scripts/kconfig/parser.tab.o
> >   HOSTCC  scripts/kconfig/preprocess.o
> >   HOSTCC  scripts/kconfig/symbol.o
> >   HOSTCC  scripts/kconfig/util.o
> >   HOSTLD  scripts/kconfig/conf
> > *** Default configuration is based on 'x86_64_defconfig'
> > #
> > # configuration written to .config
> > #
> > 
> > $ grep VHOST .config
> > # CONFIG_VHOST is not set
> > 
> >  
> >> If yes, what's your build config looks like?
> >>
> >> Thanks
> 
> This was x86. Not sure if that did work before.
> On s390 this is definitely a regression as the defconfig files 
> for s390 do select VHOST_NET
> 
> grep VHOST arch/s390/configs/*
> arch/s390/configs/debug_defconfig:CONFIG_VHOST_NET=m
> arch/s390/configs/debug_defconfig:CONFIG_VHOST_VSOCK=m
> arch/s390/configs/defconfig:CONFIG_VHOST_NET=m
> arch/s390/configs/defconfig:CONFIG_VHOST_VSOCK=m
> 
> and this worked with 5.6, but does not work with next. Just adding
> CONFIG_VHOST=m to the defconfig solves the issue, something like

And a bunch of other places I guess... and I guess we need to
select VHOST_RING too?
Also Jason, I just noticed that you added:

config VHOST_RING
        tristate
+        select VHOST_IOTLB
        help
          This option is selected by any driver which needs to access
          the host side of a virtio ring.

but are you sure this will do the right thing if VHOST_RING itself
selected?


> ---
>  arch/s390/configs/debug_defconfig | 5 +++--
>  arch/s390/configs/defconfig       | 5 +++--
>  2 files changed, 6 insertions(+), 4 deletions(-)
> 
> diff --git a/arch/s390/configs/debug_defconfig b/arch/s390/configs/debug_defconfig
> index 46038bc58c9e..0b83274341ce 100644
> --- a/arch/s390/configs/debug_defconfig
> +++ b/arch/s390/configs/debug_defconfig
> @@ -57,8 +57,6 @@ CONFIG_PROTECTED_VIRTUALIZATION_GUEST=y
>  CONFIG_CMM=m
>  CONFIG_APPLDATA_BASE=y
>  CONFIG_KVM=m
> -CONFIG_VHOST_NET=m
> -CONFIG_VHOST_VSOCK=m
>  CONFIG_OPROFILE=m
>  CONFIG_KPROBES=y
>  CONFIG_JUMP_LABEL=y
> @@ -561,6 +559,9 @@ CONFIG_VFIO_MDEV_DEVICE=m
>  CONFIG_VIRTIO_PCI=m
>  CONFIG_VIRTIO_BALLOON=m
>  CONFIG_VIRTIO_INPUT=y
> +CONFIG_VHOST=m
> +CONFIG_VHOST_NET=m
> +CONFIG_VHOST_VSOCK=m
>  CONFIG_S390_CCW_IOMMU=y
>  CONFIG_S390_AP_IOMMU=y
>  CONFIG_EXT4_FS=y
> diff --git a/arch/s390/configs/defconfig b/arch/s390/configs/defconfig
> index 7cd0648c1f4e..39e69c4e8cf7 100644
> --- a/arch/s390/configs/defconfig
> +++ b/arch/s390/configs/defconfig
> @@ -57,8 +57,6 @@ CONFIG_PROTECTED_VIRTUALIZATION_GUEST=y
>  CONFIG_CMM=m
>  CONFIG_APPLDATA_BASE=y
>  CONFIG_KVM=m
> -CONFIG_VHOST_NET=m
> -CONFIG_VHOST_VSOCK=m
>  CONFIG_OPROFILE=m
>  CONFIG_KPROBES=y
>  CONFIG_JUMP_LABEL=y
> @@ -557,6 +555,9 @@ CONFIG_VFIO_MDEV_DEVICE=m
>  CONFIG_VIRTIO_PCI=m
>  CONFIG_VIRTIO_BALLOON=m
>  CONFIG_VIRTIO_INPUT=y
> +CONFIG_VHOST=m
> +CONFIG_VHOST_NET=m
> +CONFIG_VHOST_VSOCK=m
>  CONFIG_S390_CCW_IOMMU=y
>  CONFIG_S390_AP_IOMMU=y
>  CONFIG_EXT4_FS=y
> -- 
> 2.25.1


^ permalink raw reply	[flat|nested] 38+ messages in thread

* Re: [PATCH V9 1/9] vhost: refine vhost and vringh kconfig
  2020-04-01 13:22   ` Michael S. Tsirkin
@ 2020-04-01 14:08     ` Jason Wang
  2020-04-01 14:13       ` Michael S. Tsirkin
  0 siblings, 1 reply; 38+ messages in thread
From: Jason Wang @ 2020-04-01 14:08 UTC (permalink / raw)
  To: Michael S. Tsirkin
  Cc: linux-kernel, kvm, virtualization, netdev, jgg, maxime.coquelin,
	cunming.liang, zhihong.wang, rob.miller, xiao.w.wang,
	lingshan.zhu, eperezma, lulu, parav, kevin.tian, stefanha,
	rdunlap, hch, aadam, jiri, shahafs, hanand, mhabets, gdawar,
	saugatm, vmireyno, zhangweining


On 2020/4/1 下午9:22, Michael S. Tsirkin wrote:
> On Thu, Mar 26, 2020 at 10:01:17PM +0800, Jason Wang wrote:
>> Currently, CONFIG_VHOST depends on CONFIG_VIRTUALIZATION. But vhost is
>> not necessarily for VM since it's a generic userspace and kernel
>> communication protocol. Such dependency may prevent archs without
>> virtualization support from using vhost.
>>
>> To solve this, a dedicated vhost menu is created under drivers so
>> CONIFG_VHOST can be decoupled out of CONFIG_VIRTUALIZATION.
>>
>> While at it, also squash Kconfig.vringh into vhost Kconfig file. This
>> avoids the trick of conditional inclusion from VOP or CAIF. Then it
>> will be easier to introduce new vringh users and common dependency for
>> both vringh and vhost.
>>
>> Signed-off-by: Jason Wang <jasowang@redhat.com>
> Is this just so we can drop the dependency on CONFIG_VIRTUALIZATION?
> If yes what happens if we drop this patch?


The problem is that then VHOST_RING must depend on CONFIG_VIRTUALIZATION 
(which enable VHOST_IOTLB) to work.

But it looks to me CAIF and VOP doesn't requires CONFIG_VIRTUALIZATION.


> Given the impact it had I'd like to defer it till next release if
> possible.
>
>
>> ---
>>   arch/arm/kvm/Kconfig         |  2 --
>>   arch/arm64/kvm/Kconfig       |  2 --
>>   arch/mips/kvm/Kconfig        |  2 --
>>   arch/powerpc/kvm/Kconfig     |  2 --
>>   arch/s390/kvm/Kconfig        |  4 ----
>>   arch/x86/kvm/Kconfig         |  4 ----
>>   drivers/Kconfig              |  2 ++
>>   drivers/misc/mic/Kconfig     |  4 ----
>>   drivers/net/caif/Kconfig     |  4 ----
>>   drivers/vhost/Kconfig        | 23 ++++++++++++++---------
>>   drivers/vhost/Kconfig.vringh |  6 ------
>>   11 files changed, 16 insertions(+), 39 deletions(-)
>>   delete mode 100644 drivers/vhost/Kconfig.vringh
>>
>> diff --git a/arch/arm/kvm/Kconfig b/arch/arm/kvm/Kconfig
>> index f591026347a5..be97393761bf 100644
>> --- a/arch/arm/kvm/Kconfig
>> +++ b/arch/arm/kvm/Kconfig
>> @@ -54,6 +54,4 @@ config KVM_ARM_HOST
>>   	---help---
>>   	  Provides host support for ARM processors.
>>   
>> -source "drivers/vhost/Kconfig"
>> -
>>   endif # VIRTUALIZATION
>> diff --git a/arch/arm64/kvm/Kconfig b/arch/arm64/kvm/Kconfig
>> index a475c68cbfec..449386d76441 100644
>> --- a/arch/arm64/kvm/Kconfig
>> +++ b/arch/arm64/kvm/Kconfig
>> @@ -64,6 +64,4 @@ config KVM_ARM_PMU
>>   config KVM_INDIRECT_VECTORS
>>          def_bool KVM && (HARDEN_BRANCH_PREDICTOR || HARDEN_EL2_VECTORS)
>>   
>> -source "drivers/vhost/Kconfig"
>> -
>>   endif # VIRTUALIZATION
>> diff --git a/arch/mips/kvm/Kconfig b/arch/mips/kvm/Kconfig
>> index eac25aef21e0..b91d145aa2d5 100644
>> --- a/arch/mips/kvm/Kconfig
>> +++ b/arch/mips/kvm/Kconfig
>> @@ -72,6 +72,4 @@ config KVM_MIPS_DEBUG_COP0_COUNTERS
>>   
>>   	  If unsure, say N.
>>   
>> -source "drivers/vhost/Kconfig"
>> -
>>   endif # VIRTUALIZATION
>> diff --git a/arch/powerpc/kvm/Kconfig b/arch/powerpc/kvm/Kconfig
>> index 711fca9bc6f0..12885eda324e 100644
>> --- a/arch/powerpc/kvm/Kconfig
>> +++ b/arch/powerpc/kvm/Kconfig
>> @@ -204,6 +204,4 @@ config KVM_XIVE
>>   	default y
>>   	depends on KVM_XICS && PPC_XIVE_NATIVE && KVM_BOOK3S_HV_POSSIBLE
>>   
>> -source "drivers/vhost/Kconfig"
>> -
>>   endif # VIRTUALIZATION
>> diff --git a/arch/s390/kvm/Kconfig b/arch/s390/kvm/Kconfig
>> index d3db3d7ed077..def3b60f1fe8 100644
>> --- a/arch/s390/kvm/Kconfig
>> +++ b/arch/s390/kvm/Kconfig
>> @@ -55,8 +55,4 @@ config KVM_S390_UCONTROL
>>   
>>   	  If unsure, say N.
>>   
>> -# OK, it's a little counter-intuitive to do this, but it puts it neatly under
>> -# the virtualization menu.
>> -source "drivers/vhost/Kconfig"
>> -
>>   endif # VIRTUALIZATION
>> diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig
>> index 991019d5eee1..0dfe70e17af9 100644
>> --- a/arch/x86/kvm/Kconfig
>> +++ b/arch/x86/kvm/Kconfig
>> @@ -94,8 +94,4 @@ config KVM_MMU_AUDIT
>>   	 This option adds a R/W kVM module parameter 'mmu_audit', which allows
>>   	 auditing of KVM MMU events at runtime.
>>   
>> -# OK, it's a little counter-intuitive to do this, but it puts it neatly under
>> -# the virtualization menu.
>> -source "drivers/vhost/Kconfig"
>> -
>>   endif # VIRTUALIZATION
>> diff --git a/drivers/Kconfig b/drivers/Kconfig
>> index 8befa53f43be..7a6d8b2b68b4 100644
>> --- a/drivers/Kconfig
>> +++ b/drivers/Kconfig
>> @@ -138,6 +138,8 @@ source "drivers/virt/Kconfig"
>>   
>>   source "drivers/virtio/Kconfig"
>>   
>> +source "drivers/vhost/Kconfig"
>> +
>>   source "drivers/hv/Kconfig"
>>   
>>   source "drivers/xen/Kconfig"
>> diff --git a/drivers/misc/mic/Kconfig b/drivers/misc/mic/Kconfig
>> index b6841ba6d922..8f201d019f5a 100644
>> --- a/drivers/misc/mic/Kconfig
>> +++ b/drivers/misc/mic/Kconfig
>> @@ -133,8 +133,4 @@ config VOP
>>   	  OS and tools for MIC to use with this driver are available from
>>   	  <http://software.intel.com/en-us/mic-developer>.
>>   
>> -if VOP
>> -source "drivers/vhost/Kconfig.vringh"
>> -endif
>> -
>>   endmenu
>> diff --git a/drivers/net/caif/Kconfig b/drivers/net/caif/Kconfig
>> index e74e2bb61236..9db0570c5beb 100644
>> --- a/drivers/net/caif/Kconfig
>> +++ b/drivers/net/caif/Kconfig
>> @@ -58,8 +58,4 @@ config CAIF_VIRTIO
>>   	---help---
>>   	  The CAIF driver for CAIF over Virtio.
>>   
>> -if CAIF_VIRTIO
>> -source "drivers/vhost/Kconfig.vringh"
>> -endif
>> -
>>   endif # CAIF_DRIVERS
>> diff --git a/drivers/vhost/Kconfig b/drivers/vhost/Kconfig
>> index 3d03ccbd1adc..4aef10a54cd1 100644
>> --- a/drivers/vhost/Kconfig
>> +++ b/drivers/vhost/Kconfig
>> @@ -1,8 +1,20 @@
>>   # SPDX-License-Identifier: GPL-2.0-only
>> +config VHOST_RING
>> +	tristate
>> +	help
>> +	  This option is selected by any driver which needs to access
>> +	  the host side of a virtio ring.
>> +
>> +menuconfig VHOST
>> +	tristate "Host kernel accelerator for virtio (VHOST)"
>> +	help
>> +	  This option is selected by any driver which needs to access
>> +	  the core of vhost.
>> +if VHOST
>> +
> The description here is wrong, isn't it?
> VHOST and VHOST_RING are no longer selected, right?


For VHOST not currently.

For VHOST_RING, it was selected by CAIF, VOP and VDPASIM.

Thanks


>
>
>>   config VHOST_NET
>>   	tristate "Host kernel accelerator for virtio net"
>>   	depends on NET && EVENTFD && (TUN || !TUN) && (TAP || !TAP)
>> -	select VHOST
>>   	---help---
>>   	  This kernel module can be loaded in host kernel to accelerate
>>   	  guest networking with virtio_net. Not to be confused with virtio_net
>> @@ -14,7 +26,6 @@ config VHOST_NET
>>   config VHOST_SCSI
>>   	tristate "VHOST_SCSI TCM fabric driver"
>>   	depends on TARGET_CORE && EVENTFD
>> -	select VHOST
>>   	default n
>>   	---help---
>>   	Say M here to enable the vhost_scsi TCM fabric module
>> @@ -24,7 +35,6 @@ config VHOST_VSOCK
>>   	tristate "vhost virtio-vsock driver"
>>   	depends on VSOCKETS && EVENTFD
>>   	select VIRTIO_VSOCKETS_COMMON
>> -	select VHOST
>>   	default n
>>   	---help---
>>   	This kernel module can be loaded in the host kernel to provide AF_VSOCK
>> @@ -34,12 +44,6 @@ config VHOST_VSOCK
>>   	To compile this driver as a module, choose M here: the module will be called
>>   	vhost_vsock.
>>   
>> -config VHOST
>> -	tristate
>> -	---help---
>> -	  This option is selected by any driver which needs to access
>> -	  the core of vhost.
>> -
>>   config VHOST_CROSS_ENDIAN_LEGACY
>>   	bool "Cross-endian support for vhost"
>>   	default n
>> @@ -54,3 +58,4 @@ config VHOST_CROSS_ENDIAN_LEGACY
>>   	  adds some overhead, it is disabled by default.
>>   
>>   	  If unsure, say "N".
>> +endif
>> diff --git a/drivers/vhost/Kconfig.vringh b/drivers/vhost/Kconfig.vringh
>> deleted file mode 100644
>> index c1fe36a9b8d4..000000000000
>> --- a/drivers/vhost/Kconfig.vringh
>> +++ /dev/null
>> @@ -1,6 +0,0 @@
>> -# SPDX-License-Identifier: GPL-2.0-only
>> -config VHOST_RING
>> -	tristate
>> -	---help---
>> -	  This option is selected by any driver which needs to access
>> -	  the host side of a virtio ring.
>> -- 
>> 2.20.1


^ permalink raw reply	[flat|nested] 38+ messages in thread

* Re: [PATCH V9 1/9] vhost: refine vhost and vringh kconfig
  2020-04-01 14:08     ` Jason Wang
@ 2020-04-01 14:13       ` Michael S. Tsirkin
  2020-04-01 14:29         ` Jason Wang
  0 siblings, 1 reply; 38+ messages in thread
From: Michael S. Tsirkin @ 2020-04-01 14:13 UTC (permalink / raw)
  To: Jason Wang
  Cc: linux-kernel, kvm, virtualization, netdev, jgg, maxime.coquelin,
	cunming.liang, zhihong.wang, rob.miller, xiao.w.wang,
	lingshan.zhu, eperezma, lulu, parav, kevin.tian, stefanha,
	rdunlap, hch, aadam, jiri, shahafs, hanand, mhabets, gdawar,
	saugatm, vmireyno, zhangweining

On Wed, Apr 01, 2020 at 10:08:59PM +0800, Jason Wang wrote:
> 
> On 2020/4/1 下午9:22, Michael S. Tsirkin wrote:
> > On Thu, Mar 26, 2020 at 10:01:17PM +0800, Jason Wang wrote:
> > > Currently, CONFIG_VHOST depends on CONFIG_VIRTUALIZATION. But vhost is
> > > not necessarily for VM since it's a generic userspace and kernel
> > > communication protocol. Such dependency may prevent archs without
> > > virtualization support from using vhost.
> > > 
> > > To solve this, a dedicated vhost menu is created under drivers so
> > > CONIFG_VHOST can be decoupled out of CONFIG_VIRTUALIZATION.
> > > 
> > > While at it, also squash Kconfig.vringh into vhost Kconfig file. This
> > > avoids the trick of conditional inclusion from VOP or CAIF. Then it
> > > will be easier to introduce new vringh users and common dependency for
> > > both vringh and vhost.
> > > 
> > > Signed-off-by: Jason Wang <jasowang@redhat.com>
> > Is this just so we can drop the dependency on CONFIG_VIRTUALIZATION?
> > If yes what happens if we drop this patch?
> 
> 
> The problem is that then VHOST_RING must depend on CONFIG_VIRTUALIZATION
> (which enable VHOST_IOTLB) to work.
> 
> But it looks to me CAIF and VOP doesn't requires CONFIG_VIRTUALIZATION.

How about stubs for IOTLB so VHOST_RING does not depend on VHOST_IOTLB?
I'm pretty sure neither user of vringh can actually use IOTLB, it's a
software only thing.

> 
> > Given the impact it had I'd like to defer it till next release if
> > possible.
> > 
> > 
> > > ---
> > >   arch/arm/kvm/Kconfig         |  2 --
> > >   arch/arm64/kvm/Kconfig       |  2 --
> > >   arch/mips/kvm/Kconfig        |  2 --
> > >   arch/powerpc/kvm/Kconfig     |  2 --
> > >   arch/s390/kvm/Kconfig        |  4 ----
> > >   arch/x86/kvm/Kconfig         |  4 ----
> > >   drivers/Kconfig              |  2 ++
> > >   drivers/misc/mic/Kconfig     |  4 ----
> > >   drivers/net/caif/Kconfig     |  4 ----
> > >   drivers/vhost/Kconfig        | 23 ++++++++++++++---------
> > >   drivers/vhost/Kconfig.vringh |  6 ------
> > >   11 files changed, 16 insertions(+), 39 deletions(-)
> > >   delete mode 100644 drivers/vhost/Kconfig.vringh
> > > 
> > > diff --git a/arch/arm/kvm/Kconfig b/arch/arm/kvm/Kconfig
> > > index f591026347a5..be97393761bf 100644
> > > --- a/arch/arm/kvm/Kconfig
> > > +++ b/arch/arm/kvm/Kconfig
> > > @@ -54,6 +54,4 @@ config KVM_ARM_HOST
> > >   	---help---
> > >   	  Provides host support for ARM processors.
> > > -source "drivers/vhost/Kconfig"
> > > -
> > >   endif # VIRTUALIZATION
> > > diff --git a/arch/arm64/kvm/Kconfig b/arch/arm64/kvm/Kconfig
> > > index a475c68cbfec..449386d76441 100644
> > > --- a/arch/arm64/kvm/Kconfig
> > > +++ b/arch/arm64/kvm/Kconfig
> > > @@ -64,6 +64,4 @@ config KVM_ARM_PMU
> > >   config KVM_INDIRECT_VECTORS
> > >          def_bool KVM && (HARDEN_BRANCH_PREDICTOR || HARDEN_EL2_VECTORS)
> > > -source "drivers/vhost/Kconfig"
> > > -
> > >   endif # VIRTUALIZATION
> > > diff --git a/arch/mips/kvm/Kconfig b/arch/mips/kvm/Kconfig
> > > index eac25aef21e0..b91d145aa2d5 100644
> > > --- a/arch/mips/kvm/Kconfig
> > > +++ b/arch/mips/kvm/Kconfig
> > > @@ -72,6 +72,4 @@ config KVM_MIPS_DEBUG_COP0_COUNTERS
> > >   	  If unsure, say N.
> > > -source "drivers/vhost/Kconfig"
> > > -
> > >   endif # VIRTUALIZATION
> > > diff --git a/arch/powerpc/kvm/Kconfig b/arch/powerpc/kvm/Kconfig
> > > index 711fca9bc6f0..12885eda324e 100644
> > > --- a/arch/powerpc/kvm/Kconfig
> > > +++ b/arch/powerpc/kvm/Kconfig
> > > @@ -204,6 +204,4 @@ config KVM_XIVE
> > >   	default y
> > >   	depends on KVM_XICS && PPC_XIVE_NATIVE && KVM_BOOK3S_HV_POSSIBLE
> > > -source "drivers/vhost/Kconfig"
> > > -
> > >   endif # VIRTUALIZATION
> > > diff --git a/arch/s390/kvm/Kconfig b/arch/s390/kvm/Kconfig
> > > index d3db3d7ed077..def3b60f1fe8 100644
> > > --- a/arch/s390/kvm/Kconfig
> > > +++ b/arch/s390/kvm/Kconfig
> > > @@ -55,8 +55,4 @@ config KVM_S390_UCONTROL
> > >   	  If unsure, say N.
> > > -# OK, it's a little counter-intuitive to do this, but it puts it neatly under
> > > -# the virtualization menu.
> > > -source "drivers/vhost/Kconfig"
> > > -
> > >   endif # VIRTUALIZATION
> > > diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig
> > > index 991019d5eee1..0dfe70e17af9 100644
> > > --- a/arch/x86/kvm/Kconfig
> > > +++ b/arch/x86/kvm/Kconfig
> > > @@ -94,8 +94,4 @@ config KVM_MMU_AUDIT
> > >   	 This option adds a R/W kVM module parameter 'mmu_audit', which allows
> > >   	 auditing of KVM MMU events at runtime.
> > > -# OK, it's a little counter-intuitive to do this, but it puts it neatly under
> > > -# the virtualization menu.
> > > -source "drivers/vhost/Kconfig"
> > > -
> > >   endif # VIRTUALIZATION
> > > diff --git a/drivers/Kconfig b/drivers/Kconfig
> > > index 8befa53f43be..7a6d8b2b68b4 100644
> > > --- a/drivers/Kconfig
> > > +++ b/drivers/Kconfig
> > > @@ -138,6 +138,8 @@ source "drivers/virt/Kconfig"
> > >   source "drivers/virtio/Kconfig"
> > > +source "drivers/vhost/Kconfig"
> > > +
> > >   source "drivers/hv/Kconfig"
> > >   source "drivers/xen/Kconfig"
> > > diff --git a/drivers/misc/mic/Kconfig b/drivers/misc/mic/Kconfig
> > > index b6841ba6d922..8f201d019f5a 100644
> > > --- a/drivers/misc/mic/Kconfig
> > > +++ b/drivers/misc/mic/Kconfig
> > > @@ -133,8 +133,4 @@ config VOP
> > >   	  OS and tools for MIC to use with this driver are available from
> > >   	  <http://software.intel.com/en-us/mic-developer>.
> > > -if VOP
> > > -source "drivers/vhost/Kconfig.vringh"
> > > -endif
> > > -
> > >   endmenu
> > > diff --git a/drivers/net/caif/Kconfig b/drivers/net/caif/Kconfig
> > > index e74e2bb61236..9db0570c5beb 100644
> > > --- a/drivers/net/caif/Kconfig
> > > +++ b/drivers/net/caif/Kconfig
> > > @@ -58,8 +58,4 @@ config CAIF_VIRTIO
> > >   	---help---
> > >   	  The CAIF driver for CAIF over Virtio.
> > > -if CAIF_VIRTIO
> > > -source "drivers/vhost/Kconfig.vringh"
> > > -endif
> > > -
> > >   endif # CAIF_DRIVERS
> > > diff --git a/drivers/vhost/Kconfig b/drivers/vhost/Kconfig
> > > index 3d03ccbd1adc..4aef10a54cd1 100644
> > > --- a/drivers/vhost/Kconfig
> > > +++ b/drivers/vhost/Kconfig
> > > @@ -1,8 +1,20 @@
> > >   # SPDX-License-Identifier: GPL-2.0-only
> > > +config VHOST_RING
> > > +	tristate
> > > +	help
> > > +	  This option is selected by any driver which needs to access
> > > +	  the host side of a virtio ring.
> > > +
> > > +menuconfig VHOST
> > > +	tristate "Host kernel accelerator for virtio (VHOST)"
> > > +	help
> > > +	  This option is selected by any driver which needs to access
> > > +	  the core of vhost.
> > > +if VHOST
> > > +
> > The description here is wrong, isn't it?
> > VHOST and VHOST_RING are no longer selected, right?
> 
> 
> For VHOST not currently.

Can we just bring it back and select it?

> For VHOST_RING, it was selected by CAIF, VOP and VDPASIM.
> 
> Thanks
> 
> 
> > 
> > 
> > >   config VHOST_NET
> > >   	tristate "Host kernel accelerator for virtio net"
> > >   	depends on NET && EVENTFD && (TUN || !TUN) && (TAP || !TAP)
> > > -	select VHOST
> > >   	---help---
> > >   	  This kernel module can be loaded in host kernel to accelerate
> > >   	  guest networking with virtio_net. Not to be confused with virtio_net
> > > @@ -14,7 +26,6 @@ config VHOST_NET
> > >   config VHOST_SCSI
> > >   	tristate "VHOST_SCSI TCM fabric driver"
> > >   	depends on TARGET_CORE && EVENTFD
> > > -	select VHOST
> > >   	default n
> > >   	---help---
> > >   	Say M here to enable the vhost_scsi TCM fabric module
> > > @@ -24,7 +35,6 @@ config VHOST_VSOCK
> > >   	tristate "vhost virtio-vsock driver"
> > >   	depends on VSOCKETS && EVENTFD
> > >   	select VIRTIO_VSOCKETS_COMMON
> > > -	select VHOST
> > >   	default n
> > >   	---help---
> > >   	This kernel module can be loaded in the host kernel to provide AF_VSOCK
> > > @@ -34,12 +44,6 @@ config VHOST_VSOCK
> > >   	To compile this driver as a module, choose M here: the module will be called
> > >   	vhost_vsock.
> > > -config VHOST
> > > -	tristate
> > > -	---help---
> > > -	  This option is selected by any driver which needs to access
> > > -	  the core of vhost.
> > > -
> > >   config VHOST_CROSS_ENDIAN_LEGACY
> > >   	bool "Cross-endian support for vhost"
> > >   	default n
> > > @@ -54,3 +58,4 @@ config VHOST_CROSS_ENDIAN_LEGACY
> > >   	  adds some overhead, it is disabled by default.
> > >   	  If unsure, say "N".
> > > +endif
> > > diff --git a/drivers/vhost/Kconfig.vringh b/drivers/vhost/Kconfig.vringh
> > > deleted file mode 100644
> > > index c1fe36a9b8d4..000000000000
> > > --- a/drivers/vhost/Kconfig.vringh
> > > +++ /dev/null
> > > @@ -1,6 +0,0 @@
> > > -# SPDX-License-Identifier: GPL-2.0-only
> > > -config VHOST_RING
> > > -	tristate
> > > -	---help---
> > > -	  This option is selected by any driver which needs to access
> > > -	  the host side of a virtio ring.
> > > -- 
> > > 2.20.1


^ permalink raw reply	[flat|nested] 38+ messages in thread

* Re: [PATCH V9 1/9] vhost: refine vhost and vringh kconfig
  2020-04-01 13:02         ` Christian Borntraeger
  2020-04-01 14:01           ` Michael S. Tsirkin
@ 2020-04-01 14:13           ` Jason Wang
  2020-04-01 14:18             ` Michael S. Tsirkin
  2020-04-01 14:27             ` Michael S. Tsirkin
  1 sibling, 2 replies; 38+ messages in thread
From: Jason Wang @ 2020-04-01 14:13 UTC (permalink / raw)
  To: Christian Borntraeger, mst, linux-kernel, kvm, virtualization, netdev
  Cc: jgg, maxime.coquelin, cunming.liang, zhihong.wang, rob.miller,
	xiao.w.wang, lingshan.zhu, eperezma, lulu, parav, kevin.tian,
	stefanha, rdunlap, hch, aadam, jiri, shahafs, hanand, mhabets,
	gdawar, saugatm, vmireyno, zhangweining


On 2020/4/1 下午9:02, Christian Borntraeger wrote:
>
> On 01.04.20 14:56, Christian Borntraeger wrote:
>> On 01.04.20 14:50, Jason Wang wrote:
>>> On 2020/4/1 下午7:21, Christian Borntraeger wrote:
>>>> On 26.03.20 15:01, Jason Wang wrote:
>>>>> Currently, CONFIG_VHOST depends on CONFIG_VIRTUALIZATION. But vhost is
>>>>> not necessarily for VM since it's a generic userspace and kernel
>>>>> communication protocol. Such dependency may prevent archs without
>>>>> virtualization support from using vhost.
>>>>>
>>>>> To solve this, a dedicated vhost menu is created under drivers so
>>>>> CONIFG_VHOST can be decoupled out of CONFIG_VIRTUALIZATION.
>>>> FWIW, this now results in vhost not being build with defconfig kernels (in todays
>>>> linux-next).
>>>>
>>> Hi Christian:
>>>
>>> Did you meet it even with this commit https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?id=a4be40cbcedba9b5b714f3c95182e8a45176e42d?
>> I simply used linux-next. The defconfig does NOT contain CONFIG_VHOST and therefore CONFIG_VHOST_NET and friends
>> can not be selected.
>>
>> $ git checkout next-20200401
>> $ make defconfig
>>    HOSTCC  scripts/basic/fixdep
>>    HOSTCC  scripts/kconfig/conf.o
>>    HOSTCC  scripts/kconfig/confdata.o
>>    HOSTCC  scripts/kconfig/expr.o
>>    LEX     scripts/kconfig/lexer.lex.c
>>    YACC    scripts/kconfig/parser.tab.[ch]
>>    HOSTCC  scripts/kconfig/lexer.lex.o
>>    HOSTCC  scripts/kconfig/parser.tab.o
>>    HOSTCC  scripts/kconfig/preprocess.o
>>    HOSTCC  scripts/kconfig/symbol.o
>>    HOSTCC  scripts/kconfig/util.o
>>    HOSTLD  scripts/kconfig/conf
>> *** Default configuration is based on 'x86_64_defconfig'
>> #
>> # configuration written to .config
>> #
>>
>> $ grep VHOST .config
>> # CONFIG_VHOST is not set
>>
>>   
>>> If yes, what's your build config looks like?
>>>
>>> Thanks
> This was x86. Not sure if that did work before.
> On s390 this is definitely a regression as the defconfig files
> for s390 do select VHOST_NET
>
> grep VHOST arch/s390/configs/*
> arch/s390/configs/debug_defconfig:CONFIG_VHOST_NET=m
> arch/s390/configs/debug_defconfig:CONFIG_VHOST_VSOCK=m
> arch/s390/configs/defconfig:CONFIG_VHOST_NET=m
> arch/s390/configs/defconfig:CONFIG_VHOST_VSOCK=m
>
> and this worked with 5.6, but does not work with next. Just adding
> CONFIG_VHOST=m to the defconfig solves the issue, something like


Right, I think we probably need

1) add CONFIG_VHOST=m to all defconfigs that enables 
CONFIG_VHOST_NET/VSOCK/SCSI.

or

2) don't use menuconfig for CONFIG_VHOST, let NET/SCSI/VDPA just select it.

Thanks


>
> ---
>   arch/s390/configs/debug_defconfig | 5 +++--
>   arch/s390/configs/defconfig       | 5 +++--
>   2 files changed, 6 insertions(+), 4 deletions(-)
>
> diff --git a/arch/s390/configs/debug_defconfig b/arch/s390/configs/debug_defconfig
> index 46038bc58c9e..0b83274341ce 100644
> --- a/arch/s390/configs/debug_defconfig
> +++ b/arch/s390/configs/debug_defconfig
> @@ -57,8 +57,6 @@ CONFIG_PROTECTED_VIRTUALIZATION_GUEST=y
>   CONFIG_CMM=m
>   CONFIG_APPLDATA_BASE=y
>   CONFIG_KVM=m
> -CONFIG_VHOST_NET=m
> -CONFIG_VHOST_VSOCK=m
>   CONFIG_OPROFILE=m
>   CONFIG_KPROBES=y
>   CONFIG_JUMP_LABEL=y
> @@ -561,6 +559,9 @@ CONFIG_VFIO_MDEV_DEVICE=m
>   CONFIG_VIRTIO_PCI=m
>   CONFIG_VIRTIO_BALLOON=m
>   CONFIG_VIRTIO_INPUT=y
> +CONFIG_VHOST=m
> +CONFIG_VHOST_NET=m
> +CONFIG_VHOST_VSOCK=m
>   CONFIG_S390_CCW_IOMMU=y
>   CONFIG_S390_AP_IOMMU=y
>   CONFIG_EXT4_FS=y
> diff --git a/arch/s390/configs/defconfig b/arch/s390/configs/defconfig
> index 7cd0648c1f4e..39e69c4e8cf7 100644
> --- a/arch/s390/configs/defconfig
> +++ b/arch/s390/configs/defconfig
> @@ -57,8 +57,6 @@ CONFIG_PROTECTED_VIRTUALIZATION_GUEST=y
>   CONFIG_CMM=m
>   CONFIG_APPLDATA_BASE=y
>   CONFIG_KVM=m
> -CONFIG_VHOST_NET=m
> -CONFIG_VHOST_VSOCK=m
>   CONFIG_OPROFILE=m
>   CONFIG_KPROBES=y
>   CONFIG_JUMP_LABEL=y
> @@ -557,6 +555,9 @@ CONFIG_VFIO_MDEV_DEVICE=m
>   CONFIG_VIRTIO_PCI=m
>   CONFIG_VIRTIO_BALLOON=m
>   CONFIG_VIRTIO_INPUT=y
> +CONFIG_VHOST=m
> +CONFIG_VHOST_NET=m
> +CONFIG_VHOST_VSOCK=m
>   CONFIG_S390_CCW_IOMMU=y
>   CONFIG_S390_AP_IOMMU=y
>   CONFIG_EXT4_FS=y


^ permalink raw reply	[flat|nested] 38+ messages in thread

* Re: [PATCH V9 1/9] vhost: refine vhost and vringh kconfig
  2020-04-01 14:13           ` Jason Wang
@ 2020-04-01 14:18             ` Michael S. Tsirkin
  2020-04-01 14:36               ` Jason Wang
  2020-04-01 14:27             ` Michael S. Tsirkin
  1 sibling, 1 reply; 38+ messages in thread
From: Michael S. Tsirkin @ 2020-04-01 14:18 UTC (permalink / raw)
  To: Jason Wang
  Cc: Christian Borntraeger, linux-kernel, kvm, virtualization, netdev,
	jgg, maxime.coquelin, cunming.liang, zhihong.wang, rob.miller,
	xiao.w.wang, lingshan.zhu, eperezma, lulu, parav, kevin.tian,
	stefanha, rdunlap, hch, aadam, jiri, shahafs, hanand, mhabets,
	gdawar, saugatm, vmireyno, zhangweining

On Wed, Apr 01, 2020 at 10:13:29PM +0800, Jason Wang wrote:
> 
> On 2020/4/1 下午9:02, Christian Borntraeger wrote:
> > 
> > On 01.04.20 14:56, Christian Borntraeger wrote:
> > > On 01.04.20 14:50, Jason Wang wrote:
> > > > On 2020/4/1 下午7:21, Christian Borntraeger wrote:
> > > > > On 26.03.20 15:01, Jason Wang wrote:
> > > > > > Currently, CONFIG_VHOST depends on CONFIG_VIRTUALIZATION. But vhost is
> > > > > > not necessarily for VM since it's a generic userspace and kernel
> > > > > > communication protocol. Such dependency may prevent archs without
> > > > > > virtualization support from using vhost.
> > > > > > 
> > > > > > To solve this, a dedicated vhost menu is created under drivers so
> > > > > > CONIFG_VHOST can be decoupled out of CONFIG_VIRTUALIZATION.
> > > > > FWIW, this now results in vhost not being build with defconfig kernels (in todays
> > > > > linux-next).
> > > > > 
> > > > Hi Christian:
> > > > 
> > > > Did you meet it even with this commit https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?id=a4be40cbcedba9b5b714f3c95182e8a45176e42d?
> > > I simply used linux-next. The defconfig does NOT contain CONFIG_VHOST and therefore CONFIG_VHOST_NET and friends
> > > can not be selected.
> > > 
> > > $ git checkout next-20200401
> > > $ make defconfig
> > >    HOSTCC  scripts/basic/fixdep
> > >    HOSTCC  scripts/kconfig/conf.o
> > >    HOSTCC  scripts/kconfig/confdata.o
> > >    HOSTCC  scripts/kconfig/expr.o
> > >    LEX     scripts/kconfig/lexer.lex.c
> > >    YACC    scripts/kconfig/parser.tab.[ch]
> > >    HOSTCC  scripts/kconfig/lexer.lex.o
> > >    HOSTCC  scripts/kconfig/parser.tab.o
> > >    HOSTCC  scripts/kconfig/preprocess.o
> > >    HOSTCC  scripts/kconfig/symbol.o
> > >    HOSTCC  scripts/kconfig/util.o
> > >    HOSTLD  scripts/kconfig/conf
> > > *** Default configuration is based on 'x86_64_defconfig'
> > > #
> > > # configuration written to .config
> > > #
> > > 
> > > $ grep VHOST .config
> > > # CONFIG_VHOST is not set
> > > 
> > > > If yes, what's your build config looks like?
> > > > 
> > > > Thanks
> > This was x86. Not sure if that did work before.
> > On s390 this is definitely a regression as the defconfig files
> > for s390 do select VHOST_NET
> > 
> > grep VHOST arch/s390/configs/*
> > arch/s390/configs/debug_defconfig:CONFIG_VHOST_NET=m
> > arch/s390/configs/debug_defconfig:CONFIG_VHOST_VSOCK=m
> > arch/s390/configs/defconfig:CONFIG_VHOST_NET=m
> > arch/s390/configs/defconfig:CONFIG_VHOST_VSOCK=m
> > 
> > and this worked with 5.6, but does not work with next. Just adding
> > CONFIG_VHOST=m to the defconfig solves the issue, something like
> 
> 
> Right, I think we probably need
> 
> 1) add CONFIG_VHOST=m to all defconfigs that enables
> CONFIG_VHOST_NET/VSOCK/SCSI.
> 
> or
> 
> 2) don't use menuconfig for CONFIG_VHOST, let NET/SCSI/VDPA just select it.
> 
> Thanks

I think I prefer 2, but does it auto-select VHOST_IOTLB then?
Generally what was the reason to drop select VHOST from devices?


> 
> > 
> > ---
> >   arch/s390/configs/debug_defconfig | 5 +++--
> >   arch/s390/configs/defconfig       | 5 +++--
> >   2 files changed, 6 insertions(+), 4 deletions(-)
> > 
> > diff --git a/arch/s390/configs/debug_defconfig b/arch/s390/configs/debug_defconfig
> > index 46038bc58c9e..0b83274341ce 100644
> > --- a/arch/s390/configs/debug_defconfig
> > +++ b/arch/s390/configs/debug_defconfig
> > @@ -57,8 +57,6 @@ CONFIG_PROTECTED_VIRTUALIZATION_GUEST=y
> >   CONFIG_CMM=m
> >   CONFIG_APPLDATA_BASE=y
> >   CONFIG_KVM=m
> > -CONFIG_VHOST_NET=m
> > -CONFIG_VHOST_VSOCK=m
> >   CONFIG_OPROFILE=m
> >   CONFIG_KPROBES=y
> >   CONFIG_JUMP_LABEL=y
> > @@ -561,6 +559,9 @@ CONFIG_VFIO_MDEV_DEVICE=m
> >   CONFIG_VIRTIO_PCI=m
> >   CONFIG_VIRTIO_BALLOON=m
> >   CONFIG_VIRTIO_INPUT=y
> > +CONFIG_VHOST=m
> > +CONFIG_VHOST_NET=m
> > +CONFIG_VHOST_VSOCK=m
> >   CONFIG_S390_CCW_IOMMU=y
> >   CONFIG_S390_AP_IOMMU=y
> >   CONFIG_EXT4_FS=y
> > diff --git a/arch/s390/configs/defconfig b/arch/s390/configs/defconfig
> > index 7cd0648c1f4e..39e69c4e8cf7 100644
> > --- a/arch/s390/configs/defconfig
> > +++ b/arch/s390/configs/defconfig
> > @@ -57,8 +57,6 @@ CONFIG_PROTECTED_VIRTUALIZATION_GUEST=y
> >   CONFIG_CMM=m
> >   CONFIG_APPLDATA_BASE=y
> >   CONFIG_KVM=m
> > -CONFIG_VHOST_NET=m
> > -CONFIG_VHOST_VSOCK=m
> >   CONFIG_OPROFILE=m
> >   CONFIG_KPROBES=y
> >   CONFIG_JUMP_LABEL=y
> > @@ -557,6 +555,9 @@ CONFIG_VFIO_MDEV_DEVICE=m
> >   CONFIG_VIRTIO_PCI=m
> >   CONFIG_VIRTIO_BALLOON=m
> >   CONFIG_VIRTIO_INPUT=y
> > +CONFIG_VHOST=m
> > +CONFIG_VHOST_NET=m
> > +CONFIG_VHOST_VSOCK=m
> >   CONFIG_S390_CCW_IOMMU=y
> >   CONFIG_S390_AP_IOMMU=y
> >   CONFIG_EXT4_FS=y


^ permalink raw reply	[flat|nested] 38+ messages in thread

* Re: [PATCH V9 1/9] vhost: refine vhost and vringh kconfig
  2020-04-01 14:13           ` Jason Wang
  2020-04-01 14:18             ` Michael S. Tsirkin
@ 2020-04-01 14:27             ` Michael S. Tsirkin
  2020-04-01 14:50               ` Jason Wang
  1 sibling, 1 reply; 38+ messages in thread
From: Michael S. Tsirkin @ 2020-04-01 14:27 UTC (permalink / raw)
  To: Jason Wang
  Cc: Christian Borntraeger, linux-kernel, kvm, virtualization, netdev,
	jgg, maxime.coquelin, cunming.liang, zhihong.wang, rob.miller,
	xiao.w.wang, lingshan.zhu, eperezma, lulu, parav, kevin.tian,
	stefanha, rdunlap, hch, aadam, jiri, shahafs, hanand, mhabets,
	gdawar, saugatm, vmireyno, zhangweining

On Wed, Apr 01, 2020 at 10:13:29PM +0800, Jason Wang wrote:
> 
> On 2020/4/1 下午9:02, Christian Borntraeger wrote:
> > 
> > On 01.04.20 14:56, Christian Borntraeger wrote:
> > > On 01.04.20 14:50, Jason Wang wrote:
> > > > On 2020/4/1 下午7:21, Christian Borntraeger wrote:
> > > > > On 26.03.20 15:01, Jason Wang wrote:
> > > > > > Currently, CONFIG_VHOST depends on CONFIG_VIRTUALIZATION. But vhost is
> > > > > > not necessarily for VM since it's a generic userspace and kernel
> > > > > > communication protocol. Such dependency may prevent archs without
> > > > > > virtualization support from using vhost.
> > > > > > 
> > > > > > To solve this, a dedicated vhost menu is created under drivers so
> > > > > > CONIFG_VHOST can be decoupled out of CONFIG_VIRTUALIZATION.
> > > > > FWIW, this now results in vhost not being build with defconfig kernels (in todays
> > > > > linux-next).
> > > > > 
> > > > Hi Christian:
> > > > 
> > > > Did you meet it even with this commit https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?id=a4be40cbcedba9b5b714f3c95182e8a45176e42d?
> > > I simply used linux-next. The defconfig does NOT contain CONFIG_VHOST and therefore CONFIG_VHOST_NET and friends
> > > can not be selected.
> > > 
> > > $ git checkout next-20200401
> > > $ make defconfig
> > >    HOSTCC  scripts/basic/fixdep
> > >    HOSTCC  scripts/kconfig/conf.o
> > >    HOSTCC  scripts/kconfig/confdata.o
> > >    HOSTCC  scripts/kconfig/expr.o
> > >    LEX     scripts/kconfig/lexer.lex.c
> > >    YACC    scripts/kconfig/parser.tab.[ch]
> > >    HOSTCC  scripts/kconfig/lexer.lex.o
> > >    HOSTCC  scripts/kconfig/parser.tab.o
> > >    HOSTCC  scripts/kconfig/preprocess.o
> > >    HOSTCC  scripts/kconfig/symbol.o
> > >    HOSTCC  scripts/kconfig/util.o
> > >    HOSTLD  scripts/kconfig/conf
> > > *** Default configuration is based on 'x86_64_defconfig'
> > > #
> > > # configuration written to .config
> > > #
> > > 
> > > $ grep VHOST .config
> > > # CONFIG_VHOST is not set
> > > 
> > > > If yes, what's your build config looks like?
> > > > 
> > > > Thanks
> > This was x86. Not sure if that did work before.
> > On s390 this is definitely a regression as the defconfig files
> > for s390 do select VHOST_NET
> > 
> > grep VHOST arch/s390/configs/*
> > arch/s390/configs/debug_defconfig:CONFIG_VHOST_NET=m
> > arch/s390/configs/debug_defconfig:CONFIG_VHOST_VSOCK=m
> > arch/s390/configs/defconfig:CONFIG_VHOST_NET=m
> > arch/s390/configs/defconfig:CONFIG_VHOST_VSOCK=m
> > 
> > and this worked with 5.6, but does not work with next. Just adding
> > CONFIG_VHOST=m to the defconfig solves the issue, something like
> 
> 
> Right, I think we probably need
> 
> 1) add CONFIG_VHOST=m to all defconfigs that enables
> CONFIG_VHOST_NET/VSOCK/SCSI.
> 
> or
> 
> 2) don't use menuconfig for CONFIG_VHOST, let NET/SCSI/VDPA just select it.
> 
> Thanks

OK I tried this:

diff --git a/drivers/vhost/Kconfig b/drivers/vhost/Kconfig
index 2523a1d4290a..a314b900d479 100644
--- a/drivers/vhost/Kconfig
+++ b/drivers/vhost/Kconfig
@@ -19,11 +19,10 @@ menuconfig VHOST
 	  This option is selected by any driver which needs to access
 	  the core of vhost.
 
-if VHOST
-
 config VHOST_NET
 	tristate "Host kernel accelerator for virtio net"
 	depends on NET && EVENTFD && (TUN || !TUN) && (TAP || !TAP)
+	select VHOST
 	---help---
 	  This kernel module can be loaded in host kernel to accelerate
 	  guest networking with virtio_net. Not to be confused with virtio_net
@@ -35,6 +34,7 @@ config VHOST_NET
 config VHOST_SCSI
 	tristate "VHOST_SCSI TCM fabric driver"
 	depends on TARGET_CORE && EVENTFD
+	select VHOST
 	default n
 	---help---
 	Say M here to enable the vhost_scsi TCM fabric module
@@ -44,6 +44,7 @@ config VHOST_VSOCK
 	tristate "vhost virtio-vsock driver"
 	depends on VSOCKETS && EVENTFD
 	select VIRTIO_VSOCKETS_COMMON
+	select VHOST
 	default n
 	---help---
 	This kernel module can be loaded in the host kernel to provide AF_VSOCK
@@ -57,6 +58,7 @@ config VHOST_VDPA
 	tristate "Vhost driver for vDPA-based backend"
 	depends on EVENTFD
 	select VDPA
+	select VHOST
 	help
 	  This kernel module can be loaded in host kernel to accelerate
 	  guest virtio devices with the vDPA-based backends.
@@ -78,5 +80,3 @@ config VHOST_CROSS_ENDIAN_LEGACY
 	  adds some overhead, it is disabled by default.
 
 	  If unsure, say "N".
-
-endif


But now CONFIG_VHOST is always "y", never "m".
Which I think will make it a built-in.
Didn't figure out why yet.

-- 
MST


^ permalink raw reply	[flat|nested] 38+ messages in thread

* Re: [PATCH V9 1/9] vhost: refine vhost and vringh kconfig
  2020-04-01 14:13       ` Michael S. Tsirkin
@ 2020-04-01 14:29         ` Jason Wang
  2020-04-01 14:35           ` Michael S. Tsirkin
                             ` (3 more replies)
  0 siblings, 4 replies; 38+ messages in thread
From: Jason Wang @ 2020-04-01 14:29 UTC (permalink / raw)
  To: Michael S. Tsirkin
  Cc: linux-kernel, kvm, virtualization, netdev, jgg, maxime.coquelin,
	cunming.liang, zhihong.wang, rob.miller, xiao.w.wang,
	lingshan.zhu, eperezma, lulu, parav, kevin.tian, stefanha,
	rdunlap, hch, aadam, jiri, shahafs, hanand, mhabets, gdawar,
	saugatm, vmireyno, zhangweining

[-- Attachment #1: Type: text/plain, Size: 9139 bytes --]


On 2020/4/1 下午10:13, Michael S. Tsirkin wrote:
> On Wed, Apr 01, 2020 at 10:08:59PM +0800, Jason Wang wrote:
>> On 2020/4/1 下午9:22, Michael S. Tsirkin wrote:
>>> On Thu, Mar 26, 2020 at 10:01:17PM +0800, Jason Wang wrote:
>>>> Currently, CONFIG_VHOST depends on CONFIG_VIRTUALIZATION. But vhost is
>>>> not necessarily for VM since it's a generic userspace and kernel
>>>> communication protocol. Such dependency may prevent archs without
>>>> virtualization support from using vhost.
>>>>
>>>> To solve this, a dedicated vhost menu is created under drivers so
>>>> CONIFG_VHOST can be decoupled out of CONFIG_VIRTUALIZATION.
>>>>
>>>> While at it, also squash Kconfig.vringh into vhost Kconfig file. This
>>>> avoids the trick of conditional inclusion from VOP or CAIF. Then it
>>>> will be easier to introduce new vringh users and common dependency for
>>>> both vringh and vhost.
>>>>
>>>> Signed-off-by: Jason Wang <jasowang@redhat.com>
>>> Is this just so we can drop the dependency on CONFIG_VIRTUALIZATION?
>>> If yes what happens if we drop this patch?
>>
>> The problem is that then VHOST_RING must depend on CONFIG_VIRTUALIZATION
>> (which enable VHOST_IOTLB) to work.
>>
>> But it looks to me CAIF and VOP doesn't requires CONFIG_VIRTUALIZATION.
> How about stubs for IOTLB so VHOST_RING does not depend on VHOST_IOTLB?


That could work.


> I'm pretty sure neither user of vringh can actually use IOTLB, it's a
> software only thing.


Right.


>
>>> Given the impact it had I'd like to defer it till next release if
>>> possible.
>>>
>>>
>>>> ---
>>>>    arch/arm/kvm/Kconfig         |  2 --
>>>>    arch/arm64/kvm/Kconfig       |  2 --
>>>>    arch/mips/kvm/Kconfig        |  2 --
>>>>    arch/powerpc/kvm/Kconfig     |  2 --
>>>>    arch/s390/kvm/Kconfig        |  4 ----
>>>>    arch/x86/kvm/Kconfig         |  4 ----
>>>>    drivers/Kconfig              |  2 ++
>>>>    drivers/misc/mic/Kconfig     |  4 ----
>>>>    drivers/net/caif/Kconfig     |  4 ----
>>>>    drivers/vhost/Kconfig        | 23 ++++++++++++++---------
>>>>    drivers/vhost/Kconfig.vringh |  6 ------
>>>>    11 files changed, 16 insertions(+), 39 deletions(-)
>>>>    delete mode 100644 drivers/vhost/Kconfig.vringh
>>>>
>>>> diff --git a/arch/arm/kvm/Kconfig b/arch/arm/kvm/Kconfig
>>>> index f591026347a5..be97393761bf 100644
>>>> --- a/arch/arm/kvm/Kconfig
>>>> +++ b/arch/arm/kvm/Kconfig
>>>> @@ -54,6 +54,4 @@ config KVM_ARM_HOST
>>>>    	---help---
>>>>    	  Provides host support for ARM processors.
>>>> -source "drivers/vhost/Kconfig"
>>>> -
>>>>    endif # VIRTUALIZATION
>>>> diff --git a/arch/arm64/kvm/Kconfig b/arch/arm64/kvm/Kconfig
>>>> index a475c68cbfec..449386d76441 100644
>>>> --- a/arch/arm64/kvm/Kconfig
>>>> +++ b/arch/arm64/kvm/Kconfig
>>>> @@ -64,6 +64,4 @@ config KVM_ARM_PMU
>>>>    config KVM_INDIRECT_VECTORS
>>>>           def_bool KVM && (HARDEN_BRANCH_PREDICTOR || HARDEN_EL2_VECTORS)
>>>> -source "drivers/vhost/Kconfig"
>>>> -
>>>>    endif # VIRTUALIZATION
>>>> diff --git a/arch/mips/kvm/Kconfig b/arch/mips/kvm/Kconfig
>>>> index eac25aef21e0..b91d145aa2d5 100644
>>>> --- a/arch/mips/kvm/Kconfig
>>>> +++ b/arch/mips/kvm/Kconfig
>>>> @@ -72,6 +72,4 @@ config KVM_MIPS_DEBUG_COP0_COUNTERS
>>>>    	  If unsure, say N.
>>>> -source "drivers/vhost/Kconfig"
>>>> -
>>>>    endif # VIRTUALIZATION
>>>> diff --git a/arch/powerpc/kvm/Kconfig b/arch/powerpc/kvm/Kconfig
>>>> index 711fca9bc6f0..12885eda324e 100644
>>>> --- a/arch/powerpc/kvm/Kconfig
>>>> +++ b/arch/powerpc/kvm/Kconfig
>>>> @@ -204,6 +204,4 @@ config KVM_XIVE
>>>>    	default y
>>>>    	depends on KVM_XICS && PPC_XIVE_NATIVE && KVM_BOOK3S_HV_POSSIBLE
>>>> -source "drivers/vhost/Kconfig"
>>>> -
>>>>    endif # VIRTUALIZATION
>>>> diff --git a/arch/s390/kvm/Kconfig b/arch/s390/kvm/Kconfig
>>>> index d3db3d7ed077..def3b60f1fe8 100644
>>>> --- a/arch/s390/kvm/Kconfig
>>>> +++ b/arch/s390/kvm/Kconfig
>>>> @@ -55,8 +55,4 @@ config KVM_S390_UCONTROL
>>>>    	  If unsure, say N.
>>>> -# OK, it's a little counter-intuitive to do this, but it puts it neatly under
>>>> -# the virtualization menu.
>>>> -source "drivers/vhost/Kconfig"
>>>> -
>>>>    endif # VIRTUALIZATION
>>>> diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig
>>>> index 991019d5eee1..0dfe70e17af9 100644
>>>> --- a/arch/x86/kvm/Kconfig
>>>> +++ b/arch/x86/kvm/Kconfig
>>>> @@ -94,8 +94,4 @@ config KVM_MMU_AUDIT
>>>>    	 This option adds a R/W kVM module parameter 'mmu_audit', which allows
>>>>    	 auditing of KVM MMU events at runtime.
>>>> -# OK, it's a little counter-intuitive to do this, but it puts it neatly under
>>>> -# the virtualization menu.
>>>> -source "drivers/vhost/Kconfig"
>>>> -
>>>>    endif # VIRTUALIZATION
>>>> diff --git a/drivers/Kconfig b/drivers/Kconfig
>>>> index 8befa53f43be..7a6d8b2b68b4 100644
>>>> --- a/drivers/Kconfig
>>>> +++ b/drivers/Kconfig
>>>> @@ -138,6 +138,8 @@ source "drivers/virt/Kconfig"
>>>>    source "drivers/virtio/Kconfig"
>>>> +source "drivers/vhost/Kconfig"
>>>> +
>>>>    source "drivers/hv/Kconfig"
>>>>    source "drivers/xen/Kconfig"
>>>> diff --git a/drivers/misc/mic/Kconfig b/drivers/misc/mic/Kconfig
>>>> index b6841ba6d922..8f201d019f5a 100644
>>>> --- a/drivers/misc/mic/Kconfig
>>>> +++ b/drivers/misc/mic/Kconfig
>>>> @@ -133,8 +133,4 @@ config VOP
>>>>    	  OS and tools for MIC to use with this driver are available from
>>>>    	  <http://software.intel.com/en-us/mic-developer>.
>>>> -if VOP
>>>> -source "drivers/vhost/Kconfig.vringh"
>>>> -endif
>>>> -
>>>>    endmenu
>>>> diff --git a/drivers/net/caif/Kconfig b/drivers/net/caif/Kconfig
>>>> index e74e2bb61236..9db0570c5beb 100644
>>>> --- a/drivers/net/caif/Kconfig
>>>> +++ b/drivers/net/caif/Kconfig
>>>> @@ -58,8 +58,4 @@ config CAIF_VIRTIO
>>>>    	---help---
>>>>    	  The CAIF driver for CAIF over Virtio.
>>>> -if CAIF_VIRTIO
>>>> -source "drivers/vhost/Kconfig.vringh"
>>>> -endif
>>>> -
>>>>    endif # CAIF_DRIVERS
>>>> diff --git a/drivers/vhost/Kconfig b/drivers/vhost/Kconfig
>>>> index 3d03ccbd1adc..4aef10a54cd1 100644
>>>> --- a/drivers/vhost/Kconfig
>>>> +++ b/drivers/vhost/Kconfig
>>>> @@ -1,8 +1,20 @@
>>>>    # SPDX-License-Identifier: GPL-2.0-only
>>>> +config VHOST_RING
>>>> +	tristate
>>>> +	help
>>>> +	  This option is selected by any driver which needs to access
>>>> +	  the host side of a virtio ring.
>>>> +
>>>> +menuconfig VHOST
>>>> +	tristate "Host kernel accelerator for virtio (VHOST)"
>>>> +	help
>>>> +	  This option is selected by any driver which needs to access
>>>> +	  the core of vhost.
>>>> +if VHOST
>>>> +
>>> The description here is wrong, isn't it?
>>> VHOST and VHOST_RING are no longer selected, right?
>>
>> For VHOST not currently.
> Can we just bring it back and select it?


Right, so if bring it back, we don't even need the stub.

How about something like attached?

Thanks


>
>> For VHOST_RING, it was selected by CAIF, VOP and VDPASIM.
>>
>> Thanks
>>
>>
>>>
>>>>    config VHOST_NET
>>>>    	tristate "Host kernel accelerator for virtio net"
>>>>    	depends on NET && EVENTFD && (TUN || !TUN) && (TAP || !TAP)
>>>> -	select VHOST
>>>>    	---help---
>>>>    	  This kernel module can be loaded in host kernel to accelerate
>>>>    	  guest networking with virtio_net. Not to be confused with virtio_net
>>>> @@ -14,7 +26,6 @@ config VHOST_NET
>>>>    config VHOST_SCSI
>>>>    	tristate "VHOST_SCSI TCM fabric driver"
>>>>    	depends on TARGET_CORE && EVENTFD
>>>> -	select VHOST
>>>>    	default n
>>>>    	---help---
>>>>    	Say M here to enable the vhost_scsi TCM fabric module
>>>> @@ -24,7 +35,6 @@ config VHOST_VSOCK
>>>>    	tristate "vhost virtio-vsock driver"
>>>>    	depends on VSOCKETS && EVENTFD
>>>>    	select VIRTIO_VSOCKETS_COMMON
>>>> -	select VHOST
>>>>    	default n
>>>>    	---help---
>>>>    	This kernel module can be loaded in the host kernel to provide AF_VSOCK
>>>> @@ -34,12 +44,6 @@ config VHOST_VSOCK
>>>>    	To compile this driver as a module, choose M here: the module will be called
>>>>    	vhost_vsock.
>>>> -config VHOST
>>>> -	tristate
>>>> -	---help---
>>>> -	  This option is selected by any driver which needs to access
>>>> -	  the core of vhost.
>>>> -
>>>>    config VHOST_CROSS_ENDIAN_LEGACY
>>>>    	bool "Cross-endian support for vhost"
>>>>    	default n
>>>> @@ -54,3 +58,4 @@ config VHOST_CROSS_ENDIAN_LEGACY
>>>>    	  adds some overhead, it is disabled by default.
>>>>    	  If unsure, say "N".
>>>> +endif
>>>> diff --git a/drivers/vhost/Kconfig.vringh b/drivers/vhost/Kconfig.vringh
>>>> deleted file mode 100644
>>>> index c1fe36a9b8d4..000000000000
>>>> --- a/drivers/vhost/Kconfig.vringh
>>>> +++ /dev/null
>>>> @@ -1,6 +0,0 @@
>>>> -# SPDX-License-Identifier: GPL-2.0-only
>>>> -config VHOST_RING
>>>> -	tristate
>>>> -	---help---
>>>> -	  This option is selected by any driver which needs to access
>>>> -	  the host side of a virtio ring.
>>>> -- 
>>>> 2.20.1

[-- Attachment #2: 0001-vhost-let-CONFIG_VHOST-to-be-selected-by-drivers.patch --]
[-- Type: text/x-patch, Size: 2230 bytes --]

From 9b3a5d23b8bf6b0a11e65e688335d782f8e6aa5c Mon Sep 17 00:00:00 2001
From: Jason Wang <jasowang@redhat.com>
Date: Wed, 1 Apr 2020 22:17:27 +0800
Subject: [PATCH] vhost: let CONFIG_VHOST to be selected by drivers

The defconfig on some archs enable vhost_net or vhost_vsock by
default. So instead of adding CONFIG_VHOST=m to all of those files,
simply letting CONFIG_VHOST to be selected by all of the vhost
drivers. This fixes the build on the archs with CONFIG_VHOST_NET=m in
their defconfig.

Signed-off-by: Jason Wang <jasowang@redhat.com>
---
 drivers/vhost/Kconfig | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/drivers/vhost/Kconfig b/drivers/vhost/Kconfig
index 2523a1d4290a..362b832f5338 100644
--- a/drivers/vhost/Kconfig
+++ b/drivers/vhost/Kconfig
@@ -11,19 +11,23 @@ config VHOST_RING
 	  This option is selected by any driver which needs to access
 	  the host side of a virtio ring.
 
-menuconfig VHOST
-	tristate "Host kernel accelerator for virtio (VHOST)"
-	depends on EVENTFD
+config VHOST
+	tristate
 	select VHOST_IOTLB
 	help
 	  This option is selected by any driver which needs to access
 	  the core of vhost.
 
-if VHOST
+menuconfig VHOST_MENU
+	bool "VHOST drivers"
+	default y
+
+if VHOST_MENU
 
 config VHOST_NET
 	tristate "Host kernel accelerator for virtio net"
 	depends on NET && EVENTFD && (TUN || !TUN) && (TAP || !TAP)
+	select VHOST
 	---help---
 	  This kernel module can be loaded in host kernel to accelerate
 	  guest networking with virtio_net. Not to be confused with virtio_net
@@ -35,6 +39,7 @@ config VHOST_NET
 config VHOST_SCSI
 	tristate "VHOST_SCSI TCM fabric driver"
 	depends on TARGET_CORE && EVENTFD
+	select VHOST
 	default n
 	---help---
 	Say M here to enable the vhost_scsi TCM fabric module
@@ -43,6 +48,7 @@ config VHOST_SCSI
 config VHOST_VSOCK
 	tristate "vhost virtio-vsock driver"
 	depends on VSOCKETS && EVENTFD
+	select VHOST
 	select VIRTIO_VSOCKETS_COMMON
 	default n
 	---help---
@@ -56,6 +62,7 @@ config VHOST_VSOCK
 config VHOST_VDPA
 	tristate "Vhost driver for vDPA-based backend"
 	depends on EVENTFD
+	select VHOST
 	select VDPA
 	help
 	  This kernel module can be loaded in host kernel to accelerate
-- 
2.20.1


^ permalink raw reply	[flat|nested] 38+ messages in thread

* Re: [PATCH V9 1/9] vhost: refine vhost and vringh kconfig
  2020-04-01 14:29         ` Jason Wang
@ 2020-04-01 14:35           ` Michael S. Tsirkin
  2020-04-01 14:39             ` Jason Wang
  2020-04-01 14:39           ` Michael S. Tsirkin
                             ` (2 subsequent siblings)
  3 siblings, 1 reply; 38+ messages in thread
From: Michael S. Tsirkin @ 2020-04-01 14:35 UTC (permalink / raw)
  To: Jason Wang
  Cc: linux-kernel, kvm, virtualization, netdev, jgg, maxime.coquelin,
	cunming.liang, zhihong.wang, rob.miller, xiao.w.wang,
	lingshan.zhu, eperezma, lulu, parav, kevin.tian, stefanha,
	rdunlap, hch, aadam, jiri, shahafs, hanand, mhabets, gdawar,
	saugatm, vmireyno, zhangweining

On Wed, Apr 01, 2020 at 10:29:32PM +0800, Jason Wang wrote:
> 
> On 2020/4/1 下午10:13, Michael S. Tsirkin wrote:
> > On Wed, Apr 01, 2020 at 10:08:59PM +0800, Jason Wang wrote:
> > > On 2020/4/1 下午9:22, Michael S. Tsirkin wrote:
> > > > On Thu, Mar 26, 2020 at 10:01:17PM +0800, Jason Wang wrote:
> > > > > Currently, CONFIG_VHOST depends on CONFIG_VIRTUALIZATION. But vhost is
> > > > > not necessarily for VM since it's a generic userspace and kernel
> > > > > communication protocol. Such dependency may prevent archs without
> > > > > virtualization support from using vhost.
> > > > > 
> > > > > To solve this, a dedicated vhost menu is created under drivers so
> > > > > CONIFG_VHOST can be decoupled out of CONFIG_VIRTUALIZATION.
> > > > > 
> > > > > While at it, also squash Kconfig.vringh into vhost Kconfig file. This
> > > > > avoids the trick of conditional inclusion from VOP or CAIF. Then it
> > > > > will be easier to introduce new vringh users and common dependency for
> > > > > both vringh and vhost.
> > > > > 
> > > > > Signed-off-by: Jason Wang <jasowang@redhat.com>
> > > > Is this just so we can drop the dependency on CONFIG_VIRTUALIZATION?
> > > > If yes what happens if we drop this patch?
> > > 
> > > The problem is that then VHOST_RING must depend on CONFIG_VIRTUALIZATION
> > > (which enable VHOST_IOTLB) to work.
> > > 
> > > But it looks to me CAIF and VOP doesn't requires CONFIG_VIRTUALIZATION.
> > How about stubs for IOTLB so VHOST_RING does not depend on VHOST_IOTLB?
> 
> 
> That could work.
> 
> 
> > I'm pretty sure neither user of vringh can actually use IOTLB, it's a
> > software only thing.
> 
> 
> Right.
> 
> 
> > 
> > > > Given the impact it had I'd like to defer it till next release if
> > > > possible.
> > > > 
> > > > 
> > > > > ---
> > > > >    arch/arm/kvm/Kconfig         |  2 --
> > > > >    arch/arm64/kvm/Kconfig       |  2 --
> > > > >    arch/mips/kvm/Kconfig        |  2 --
> > > > >    arch/powerpc/kvm/Kconfig     |  2 --
> > > > >    arch/s390/kvm/Kconfig        |  4 ----
> > > > >    arch/x86/kvm/Kconfig         |  4 ----
> > > > >    drivers/Kconfig              |  2 ++
> > > > >    drivers/misc/mic/Kconfig     |  4 ----
> > > > >    drivers/net/caif/Kconfig     |  4 ----
> > > > >    drivers/vhost/Kconfig        | 23 ++++++++++++++---------
> > > > >    drivers/vhost/Kconfig.vringh |  6 ------
> > > > >    11 files changed, 16 insertions(+), 39 deletions(-)
> > > > >    delete mode 100644 drivers/vhost/Kconfig.vringh
> > > > > 
> > > > > diff --git a/arch/arm/kvm/Kconfig b/arch/arm/kvm/Kconfig
> > > > > index f591026347a5..be97393761bf 100644
> > > > > --- a/arch/arm/kvm/Kconfig
> > > > > +++ b/arch/arm/kvm/Kconfig
> > > > > @@ -54,6 +54,4 @@ config KVM_ARM_HOST
> > > > >    	---help---
> > > > >    	  Provides host support for ARM processors.
> > > > > -source "drivers/vhost/Kconfig"
> > > > > -
> > > > >    endif # VIRTUALIZATION
> > > > > diff --git a/arch/arm64/kvm/Kconfig b/arch/arm64/kvm/Kconfig
> > > > > index a475c68cbfec..449386d76441 100644
> > > > > --- a/arch/arm64/kvm/Kconfig
> > > > > +++ b/arch/arm64/kvm/Kconfig
> > > > > @@ -64,6 +64,4 @@ config KVM_ARM_PMU
> > > > >    config KVM_INDIRECT_VECTORS
> > > > >           def_bool KVM && (HARDEN_BRANCH_PREDICTOR || HARDEN_EL2_VECTORS)
> > > > > -source "drivers/vhost/Kconfig"
> > > > > -
> > > > >    endif # VIRTUALIZATION
> > > > > diff --git a/arch/mips/kvm/Kconfig b/arch/mips/kvm/Kconfig
> > > > > index eac25aef21e0..b91d145aa2d5 100644
> > > > > --- a/arch/mips/kvm/Kconfig
> > > > > +++ b/arch/mips/kvm/Kconfig
> > > > > @@ -72,6 +72,4 @@ config KVM_MIPS_DEBUG_COP0_COUNTERS
> > > > >    	  If unsure, say N.
> > > > > -source "drivers/vhost/Kconfig"
> > > > > -
> > > > >    endif # VIRTUALIZATION
> > > > > diff --git a/arch/powerpc/kvm/Kconfig b/arch/powerpc/kvm/Kconfig
> > > > > index 711fca9bc6f0..12885eda324e 100644
> > > > > --- a/arch/powerpc/kvm/Kconfig
> > > > > +++ b/arch/powerpc/kvm/Kconfig
> > > > > @@ -204,6 +204,4 @@ config KVM_XIVE
> > > > >    	default y
> > > > >    	depends on KVM_XICS && PPC_XIVE_NATIVE && KVM_BOOK3S_HV_POSSIBLE
> > > > > -source "drivers/vhost/Kconfig"
> > > > > -
> > > > >    endif # VIRTUALIZATION
> > > > > diff --git a/arch/s390/kvm/Kconfig b/arch/s390/kvm/Kconfig
> > > > > index d3db3d7ed077..def3b60f1fe8 100644
> > > > > --- a/arch/s390/kvm/Kconfig
> > > > > +++ b/arch/s390/kvm/Kconfig
> > > > > @@ -55,8 +55,4 @@ config KVM_S390_UCONTROL
> > > > >    	  If unsure, say N.
> > > > > -# OK, it's a little counter-intuitive to do this, but it puts it neatly under
> > > > > -# the virtualization menu.
> > > > > -source "drivers/vhost/Kconfig"
> > > > > -
> > > > >    endif # VIRTUALIZATION
> > > > > diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig
> > > > > index 991019d5eee1..0dfe70e17af9 100644
> > > > > --- a/arch/x86/kvm/Kconfig
> > > > > +++ b/arch/x86/kvm/Kconfig
> > > > > @@ -94,8 +94,4 @@ config KVM_MMU_AUDIT
> > > > >    	 This option adds a R/W kVM module parameter 'mmu_audit', which allows
> > > > >    	 auditing of KVM MMU events at runtime.
> > > > > -# OK, it's a little counter-intuitive to do this, but it puts it neatly under
> > > > > -# the virtualization menu.
> > > > > -source "drivers/vhost/Kconfig"
> > > > > -
> > > > >    endif # VIRTUALIZATION
> > > > > diff --git a/drivers/Kconfig b/drivers/Kconfig
> > > > > index 8befa53f43be..7a6d8b2b68b4 100644
> > > > > --- a/drivers/Kconfig
> > > > > +++ b/drivers/Kconfig
> > > > > @@ -138,6 +138,8 @@ source "drivers/virt/Kconfig"
> > > > >    source "drivers/virtio/Kconfig"
> > > > > +source "drivers/vhost/Kconfig"
> > > > > +
> > > > >    source "drivers/hv/Kconfig"
> > > > >    source "drivers/xen/Kconfig"
> > > > > diff --git a/drivers/misc/mic/Kconfig b/drivers/misc/mic/Kconfig
> > > > > index b6841ba6d922..8f201d019f5a 100644
> > > > > --- a/drivers/misc/mic/Kconfig
> > > > > +++ b/drivers/misc/mic/Kconfig
> > > > > @@ -133,8 +133,4 @@ config VOP
> > > > >    	  OS and tools for MIC to use with this driver are available from
> > > > >    	  <http://software.intel.com/en-us/mic-developer>.
> > > > > -if VOP
> > > > > -source "drivers/vhost/Kconfig.vringh"
> > > > > -endif
> > > > > -
> > > > >    endmenu
> > > > > diff --git a/drivers/net/caif/Kconfig b/drivers/net/caif/Kconfig
> > > > > index e74e2bb61236..9db0570c5beb 100644
> > > > > --- a/drivers/net/caif/Kconfig
> > > > > +++ b/drivers/net/caif/Kconfig
> > > > > @@ -58,8 +58,4 @@ config CAIF_VIRTIO
> > > > >    	---help---
> > > > >    	  The CAIF driver for CAIF over Virtio.
> > > > > -if CAIF_VIRTIO
> > > > > -source "drivers/vhost/Kconfig.vringh"
> > > > > -endif
> > > > > -
> > > > >    endif # CAIF_DRIVERS
> > > > > diff --git a/drivers/vhost/Kconfig b/drivers/vhost/Kconfig
> > > > > index 3d03ccbd1adc..4aef10a54cd1 100644
> > > > > --- a/drivers/vhost/Kconfig
> > > > > +++ b/drivers/vhost/Kconfig
> > > > > @@ -1,8 +1,20 @@
> > > > >    # SPDX-License-Identifier: GPL-2.0-only
> > > > > +config VHOST_RING
> > > > > +	tristate
> > > > > +	help
> > > > > +	  This option is selected by any driver which needs to access
> > > > > +	  the host side of a virtio ring.
> > > > > +
> > > > > +menuconfig VHOST
> > > > > +	tristate "Host kernel accelerator for virtio (VHOST)"
> > > > > +	help
> > > > > +	  This option is selected by any driver which needs to access
> > > > > +	  the core of vhost.
> > > > > +if VHOST
> > > > > +
> > > > The description here is wrong, isn't it?
> > > > VHOST and VHOST_RING are no longer selected, right?
> > > 
> > > For VHOST not currently.
> > Can we just bring it back and select it?
> 
> 
> Right, so if bring it back, we don't even need the stub.
> 
> How about something like attached?
> 
> Thanks
> 
> > 
> > > For VHOST_RING, it was selected by CAIF, VOP and VDPASIM.
> > > 
> > > Thanks
> > > 
> > > 
> > > > 
> > > > >    config VHOST_NET
> > > > >    	tristate "Host kernel accelerator for virtio net"
> > > > >    	depends on NET && EVENTFD && (TUN || !TUN) && (TAP || !TAP)
> > > > > -	select VHOST
> > > > >    	---help---
> > > > >    	  This kernel module can be loaded in host kernel to accelerate
> > > > >    	  guest networking with virtio_net. Not to be confused with virtio_net
> > > > > @@ -14,7 +26,6 @@ config VHOST_NET
> > > > >    config VHOST_SCSI
> > > > >    	tristate "VHOST_SCSI TCM fabric driver"
> > > > >    	depends on TARGET_CORE && EVENTFD
> > > > > -	select VHOST
> > > > >    	default n
> > > > >    	---help---
> > > > >    	Say M here to enable the vhost_scsi TCM fabric module
> > > > > @@ -24,7 +35,6 @@ config VHOST_VSOCK
> > > > >    	tristate "vhost virtio-vsock driver"
> > > > >    	depends on VSOCKETS && EVENTFD
> > > > >    	select VIRTIO_VSOCKETS_COMMON
> > > > > -	select VHOST
> > > > >    	default n
> > > > >    	---help---
> > > > >    	This kernel module can be loaded in the host kernel to provide AF_VSOCK
> > > > > @@ -34,12 +44,6 @@ config VHOST_VSOCK
> > > > >    	To compile this driver as a module, choose M here: the module will be called
> > > > >    	vhost_vsock.
> > > > > -config VHOST
> > > > > -	tristate
> > > > > -	---help---
> > > > > -	  This option is selected by any driver which needs to access
> > > > > -	  the core of vhost.
> > > > > -
> > > > >    config VHOST_CROSS_ENDIAN_LEGACY
> > > > >    	bool "Cross-endian support for vhost"
> > > > >    	default n
> > > > > @@ -54,3 +58,4 @@ config VHOST_CROSS_ENDIAN_LEGACY
> > > > >    	  adds some overhead, it is disabled by default.
> > > > >    	  If unsure, say "N".
> > > > > +endif
> > > > > diff --git a/drivers/vhost/Kconfig.vringh b/drivers/vhost/Kconfig.vringh
> > > > > deleted file mode 100644
> > > > > index c1fe36a9b8d4..000000000000
> > > > > --- a/drivers/vhost/Kconfig.vringh
> > > > > +++ /dev/null
> > > > > @@ -1,6 +0,0 @@
> > > > > -# SPDX-License-Identifier: GPL-2.0-only
> > > > > -config VHOST_RING
> > > > > -	tristate
> > > > > -	---help---
> > > > > -	  This option is selected by any driver which needs to access
> > > > > -	  the host side of a virtio ring.
> > > > > -- 
> > > > > 2.20.1

> >From 9b3a5d23b8bf6b0a11e65e688335d782f8e6aa5c Mon Sep 17 00:00:00 2001
> From: Jason Wang <jasowang@redhat.com>
> Date: Wed, 1 Apr 2020 22:17:27 +0800
> Subject: [PATCH] vhost: let CONFIG_VHOST to be selected by drivers
> 
> The defconfig on some archs enable vhost_net or vhost_vsock by
> default. So instead of adding CONFIG_VHOST=m to all of those files,
> simply letting CONFIG_VHOST to be selected by all of the vhost
> drivers. This fixes the build on the archs with CONFIG_VHOST_NET=m in
> their defconfig.
> 
> Signed-off-by: Jason Wang <jasowang@redhat.com>
> ---
>  drivers/vhost/Kconfig | 15 +++++++++++----
>  1 file changed, 11 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/vhost/Kconfig b/drivers/vhost/Kconfig
> index 2523a1d4290a..362b832f5338 100644
> --- a/drivers/vhost/Kconfig
> +++ b/drivers/vhost/Kconfig
> @@ -11,19 +11,23 @@ config VHOST_RING
>  	  This option is selected by any driver which needs to access
>  	  the host side of a virtio ring.
>  
> -menuconfig VHOST
> -	tristate "Host kernel accelerator for virtio (VHOST)"
> -	depends on EVENTFD
> +config VHOST
> +	tristate
>  	select VHOST_IOTLB
>  	help
>  	  This option is selected by any driver which needs to access
>  	  the core of vhost.
>  
> -if VHOST
> +menuconfig VHOST_MENU
> +	bool "VHOST drivers"
> +	default y
> +
> +if VHOST_MENU

Will this not still have the problem with defconfigs? They don't set
VHOST_MENU ...

>  
>  config VHOST_NET
>  	tristate "Host kernel accelerator for virtio net"
>  	depends on NET && EVENTFD && (TUN || !TUN) && (TAP || !TAP)
> +	select VHOST
>  	---help---
>  	  This kernel module can be loaded in host kernel to accelerate
>  	  guest networking with virtio_net. Not to be confused with virtio_net
> @@ -35,6 +39,7 @@ config VHOST_NET
>  config VHOST_SCSI
>  	tristate "VHOST_SCSI TCM fabric driver"
>  	depends on TARGET_CORE && EVENTFD
> +	select VHOST
>  	default n
>  	---help---
>  	Say M here to enable the vhost_scsi TCM fabric module
> @@ -43,6 +48,7 @@ config VHOST_SCSI
>  config VHOST_VSOCK
>  	tristate "vhost virtio-vsock driver"
>  	depends on VSOCKETS && EVENTFD
> +	select VHOST
>  	select VIRTIO_VSOCKETS_COMMON
>  	default n
>  	---help---
> @@ -56,6 +62,7 @@ config VHOST_VSOCK
>  config VHOST_VDPA
>  	tristate "Vhost driver for vDPA-based backend"
>  	depends on EVENTFD
> +	select VHOST
>  	select VDPA
>  	help
>  	  This kernel module can be loaded in host kernel to accelerate
> -- 
> 2.20.1
> 


^ permalink raw reply	[flat|nested] 38+ messages in thread

* Re: [PATCH V9 1/9] vhost: refine vhost and vringh kconfig
  2020-04-01 14:18             ` Michael S. Tsirkin
@ 2020-04-01 14:36               ` Jason Wang
  0 siblings, 0 replies; 38+ messages in thread
From: Jason Wang @ 2020-04-01 14:36 UTC (permalink / raw)
  To: Michael S. Tsirkin
  Cc: Christian Borntraeger, linux-kernel, kvm, virtualization, netdev,
	jgg, maxime.coquelin, cunming.liang, zhihong.wang, rob.miller,
	xiao.w.wang, lingshan.zhu, eperezma, lulu, parav, kevin.tian,
	stefanha, rdunlap, hch, aadam, jiri, shahafs, hanand, mhabets,
	gdawar, saugatm, vmireyno, zhangweining


On 2020/4/1 下午10:18, Michael S. Tsirkin wrote:
> On Wed, Apr 01, 2020 at 10:13:29PM +0800, Jason Wang wrote:
>> On 2020/4/1 下午9:02, Christian Borntraeger wrote:
>>> On 01.04.20 14:56, Christian Borntraeger wrote:
>>>> On 01.04.20 14:50, Jason Wang wrote:
>>>>> On 2020/4/1 下午7:21, Christian Borntraeger wrote:
>>>>>> On 26.03.20 15:01, Jason Wang wrote:
>>>>>>> Currently, CONFIG_VHOST depends on CONFIG_VIRTUALIZATION. But vhost is
>>>>>>> not necessarily for VM since it's a generic userspace and kernel
>>>>>>> communication protocol. Such dependency may prevent archs without
>>>>>>> virtualization support from using vhost.
>>>>>>>
>>>>>>> To solve this, a dedicated vhost menu is created under drivers so
>>>>>>> CONIFG_VHOST can be decoupled out of CONFIG_VIRTUALIZATION.
>>>>>> FWIW, this now results in vhost not being build with defconfig kernels (in todays
>>>>>> linux-next).
>>>>>>
>>>>> Hi Christian:
>>>>>
>>>>> Did you meet it even with this commithttps://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?id=a4be40cbcedba9b5b714f3c95182e8a45176e42d?
>>>> I simply used linux-next. The defconfig does NOT contain CONFIG_VHOST and therefore CONFIG_VHOST_NET and friends
>>>> can not be selected.
>>>>
>>>> $ git checkout next-20200401
>>>> $ make defconfig
>>>>     HOSTCC  scripts/basic/fixdep
>>>>     HOSTCC  scripts/kconfig/conf.o
>>>>     HOSTCC  scripts/kconfig/confdata.o
>>>>     HOSTCC  scripts/kconfig/expr.o
>>>>     LEX     scripts/kconfig/lexer.lex.c
>>>>     YACC    scripts/kconfig/parser.tab.[ch]
>>>>     HOSTCC  scripts/kconfig/lexer.lex.o
>>>>     HOSTCC  scripts/kconfig/parser.tab.o
>>>>     HOSTCC  scripts/kconfig/preprocess.o
>>>>     HOSTCC  scripts/kconfig/symbol.o
>>>>     HOSTCC  scripts/kconfig/util.o
>>>>     HOSTLD  scripts/kconfig/conf
>>>> *** Default configuration is based on 'x86_64_defconfig'
>>>> #
>>>> # configuration written to .config
>>>> #
>>>>
>>>> $ grep VHOST .config
>>>> # CONFIG_VHOST is not set
>>>>
>>>>> If yes, what's your build config looks like?
>>>>>
>>>>> Thanks
>>> This was x86. Not sure if that did work before.
>>> On s390 this is definitely a regression as the defconfig files
>>> for s390 do select VHOST_NET
>>>
>>> grep VHOST arch/s390/configs/*
>>> arch/s390/configs/debug_defconfig:CONFIG_VHOST_NET=m
>>> arch/s390/configs/debug_defconfig:CONFIG_VHOST_VSOCK=m
>>> arch/s390/configs/defconfig:CONFIG_VHOST_NET=m
>>> arch/s390/configs/defconfig:CONFIG_VHOST_VSOCK=m
>>>
>>> and this worked with 5.6, but does not work with next. Just adding
>>> CONFIG_VHOST=m to the defconfig solves the issue, something like
>> Right, I think we probably need
>>
>> 1) add CONFIG_VHOST=m to all defconfigs that enables
>> CONFIG_VHOST_NET/VSOCK/SCSI.
>>
>> or
>>
>> 2) don't use menuconfig for CONFIG_VHOST, let NET/SCSI/VDPA just select it.
>>
>> Thanks
> I think I prefer 2, but does it auto-select VHOST_IOTLB then?


I think so. E.g VHOST_NET will select VHOST,  and VHOST will select 
VHOST_IOTLB.


> Generally what was the reason to drop select VHOST from devices?
>
>

The reason is a sub menu is needed for VHOST devices, then I use 
menuconfig for CONFIG_VHOST.

Then select is not necessary anymore.

Thanks



^ permalink raw reply	[flat|nested] 38+ messages in thread

* Re: [PATCH V9 1/9] vhost: refine vhost and vringh kconfig
  2020-04-01 14:29         ` Jason Wang
  2020-04-01 14:35           ` Michael S. Tsirkin
@ 2020-04-01 14:39           ` Michael S. Tsirkin
  2020-04-01 14:43             ` Jason Wang
  2020-04-01 16:05           ` Michael S. Tsirkin
  2020-04-01 16:08           ` Michael S. Tsirkin
  3 siblings, 1 reply; 38+ messages in thread
From: Michael S. Tsirkin @ 2020-04-01 14:39 UTC (permalink / raw)
  To: Jason Wang
  Cc: linux-kernel, kvm, virtualization, netdev, jgg, maxime.coquelin,
	cunming.liang, zhihong.wang, rob.miller, xiao.w.wang,
	lingshan.zhu, eperezma, lulu, parav, kevin.tian, stefanha,
	rdunlap, hch, aadam, jiri, shahafs, hanand, mhabets, gdawar,
	saugatm, vmireyno, zhangweining

On Wed, Apr 01, 2020 at 10:29:32PM +0800, Jason Wang wrote:
> 
> On 2020/4/1 下午10:13, Michael S. Tsirkin wrote:
> > On Wed, Apr 01, 2020 at 10:08:59PM +0800, Jason Wang wrote:
> > > On 2020/4/1 下午9:22, Michael S. Tsirkin wrote:
> > > > On Thu, Mar 26, 2020 at 10:01:17PM +0800, Jason Wang wrote:
> > > > > Currently, CONFIG_VHOST depends on CONFIG_VIRTUALIZATION. But vhost is
> > > > > not necessarily for VM since it's a generic userspace and kernel
> > > > > communication protocol. Such dependency may prevent archs without
> > > > > virtualization support from using vhost.
> > > > > 
> > > > > To solve this, a dedicated vhost menu is created under drivers so
> > > > > CONIFG_VHOST can be decoupled out of CONFIG_VIRTUALIZATION.
> > > > > 
> > > > > While at it, also squash Kconfig.vringh into vhost Kconfig file. This
> > > > > avoids the trick of conditional inclusion from VOP or CAIF. Then it
> > > > > will be easier to introduce new vringh users and common dependency for
> > > > > both vringh and vhost.
> > > > > 
> > > > > Signed-off-by: Jason Wang <jasowang@redhat.com>
> > > > Is this just so we can drop the dependency on CONFIG_VIRTUALIZATION?
> > > > If yes what happens if we drop this patch?
> > > 
> > > The problem is that then VHOST_RING must depend on CONFIG_VIRTUALIZATION
> > > (which enable VHOST_IOTLB) to work.
> > > 
> > > But it looks to me CAIF and VOP doesn't requires CONFIG_VIRTUALIZATION.
> > How about stubs for IOTLB so VHOST_RING does not depend on VHOST_IOTLB?
> 
> 
> That could work.
> 
> 
> > I'm pretty sure neither user of vringh can actually use IOTLB, it's a
> > software only thing.
> 
> 
> Right.
> 
> 
> > 
> > > > Given the impact it had I'd like to defer it till next release if
> > > > possible.
> > > > 
> > > > 
> > > > > ---
> > > > >    arch/arm/kvm/Kconfig         |  2 --
> > > > >    arch/arm64/kvm/Kconfig       |  2 --
> > > > >    arch/mips/kvm/Kconfig        |  2 --
> > > > >    arch/powerpc/kvm/Kconfig     |  2 --
> > > > >    arch/s390/kvm/Kconfig        |  4 ----
> > > > >    arch/x86/kvm/Kconfig         |  4 ----
> > > > >    drivers/Kconfig              |  2 ++
> > > > >    drivers/misc/mic/Kconfig     |  4 ----
> > > > >    drivers/net/caif/Kconfig     |  4 ----
> > > > >    drivers/vhost/Kconfig        | 23 ++++++++++++++---------
> > > > >    drivers/vhost/Kconfig.vringh |  6 ------
> > > > >    11 files changed, 16 insertions(+), 39 deletions(-)
> > > > >    delete mode 100644 drivers/vhost/Kconfig.vringh
> > > > > 
> > > > > diff --git a/arch/arm/kvm/Kconfig b/arch/arm/kvm/Kconfig
> > > > > index f591026347a5..be97393761bf 100644
> > > > > --- a/arch/arm/kvm/Kconfig
> > > > > +++ b/arch/arm/kvm/Kconfig
> > > > > @@ -54,6 +54,4 @@ config KVM_ARM_HOST
> > > > >    	---help---
> > > > >    	  Provides host support for ARM processors.
> > > > > -source "drivers/vhost/Kconfig"
> > > > > -
> > > > >    endif # VIRTUALIZATION
> > > > > diff --git a/arch/arm64/kvm/Kconfig b/arch/arm64/kvm/Kconfig
> > > > > index a475c68cbfec..449386d76441 100644
> > > > > --- a/arch/arm64/kvm/Kconfig
> > > > > +++ b/arch/arm64/kvm/Kconfig
> > > > > @@ -64,6 +64,4 @@ config KVM_ARM_PMU
> > > > >    config KVM_INDIRECT_VECTORS
> > > > >           def_bool KVM && (HARDEN_BRANCH_PREDICTOR || HARDEN_EL2_VECTORS)
> > > > > -source "drivers/vhost/Kconfig"
> > > > > -
> > > > >    endif # VIRTUALIZATION
> > > > > diff --git a/arch/mips/kvm/Kconfig b/arch/mips/kvm/Kconfig
> > > > > index eac25aef21e0..b91d145aa2d5 100644
> > > > > --- a/arch/mips/kvm/Kconfig
> > > > > +++ b/arch/mips/kvm/Kconfig
> > > > > @@ -72,6 +72,4 @@ config KVM_MIPS_DEBUG_COP0_COUNTERS
> > > > >    	  If unsure, say N.
> > > > > -source "drivers/vhost/Kconfig"
> > > > > -
> > > > >    endif # VIRTUALIZATION
> > > > > diff --git a/arch/powerpc/kvm/Kconfig b/arch/powerpc/kvm/Kconfig
> > > > > index 711fca9bc6f0..12885eda324e 100644
> > > > > --- a/arch/powerpc/kvm/Kconfig
> > > > > +++ b/arch/powerpc/kvm/Kconfig
> > > > > @@ -204,6 +204,4 @@ config KVM_XIVE
> > > > >    	default y
> > > > >    	depends on KVM_XICS && PPC_XIVE_NATIVE && KVM_BOOK3S_HV_POSSIBLE
> > > > > -source "drivers/vhost/Kconfig"
> > > > > -
> > > > >    endif # VIRTUALIZATION
> > > > > diff --git a/arch/s390/kvm/Kconfig b/arch/s390/kvm/Kconfig
> > > > > index d3db3d7ed077..def3b60f1fe8 100644
> > > > > --- a/arch/s390/kvm/Kconfig
> > > > > +++ b/arch/s390/kvm/Kconfig
> > > > > @@ -55,8 +55,4 @@ config KVM_S390_UCONTROL
> > > > >    	  If unsure, say N.
> > > > > -# OK, it's a little counter-intuitive to do this, but it puts it neatly under
> > > > > -# the virtualization menu.
> > > > > -source "drivers/vhost/Kconfig"
> > > > > -
> > > > >    endif # VIRTUALIZATION
> > > > > diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig
> > > > > index 991019d5eee1..0dfe70e17af9 100644
> > > > > --- a/arch/x86/kvm/Kconfig
> > > > > +++ b/arch/x86/kvm/Kconfig
> > > > > @@ -94,8 +94,4 @@ config KVM_MMU_AUDIT
> > > > >    	 This option adds a R/W kVM module parameter 'mmu_audit', which allows
> > > > >    	 auditing of KVM MMU events at runtime.
> > > > > -# OK, it's a little counter-intuitive to do this, but it puts it neatly under
> > > > > -# the virtualization menu.
> > > > > -source "drivers/vhost/Kconfig"
> > > > > -
> > > > >    endif # VIRTUALIZATION
> > > > > diff --git a/drivers/Kconfig b/drivers/Kconfig
> > > > > index 8befa53f43be..7a6d8b2b68b4 100644
> > > > > --- a/drivers/Kconfig
> > > > > +++ b/drivers/Kconfig
> > > > > @@ -138,6 +138,8 @@ source "drivers/virt/Kconfig"
> > > > >    source "drivers/virtio/Kconfig"
> > > > > +source "drivers/vhost/Kconfig"
> > > > > +
> > > > >    source "drivers/hv/Kconfig"
> > > > >    source "drivers/xen/Kconfig"
> > > > > diff --git a/drivers/misc/mic/Kconfig b/drivers/misc/mic/Kconfig
> > > > > index b6841ba6d922..8f201d019f5a 100644
> > > > > --- a/drivers/misc/mic/Kconfig
> > > > > +++ b/drivers/misc/mic/Kconfig
> > > > > @@ -133,8 +133,4 @@ config VOP
> > > > >    	  OS and tools for MIC to use with this driver are available from
> > > > >    	  <http://software.intel.com/en-us/mic-developer>.
> > > > > -if VOP
> > > > > -source "drivers/vhost/Kconfig.vringh"
> > > > > -endif
> > > > > -
> > > > >    endmenu
> > > > > diff --git a/drivers/net/caif/Kconfig b/drivers/net/caif/Kconfig
> > > > > index e74e2bb61236..9db0570c5beb 100644
> > > > > --- a/drivers/net/caif/Kconfig
> > > > > +++ b/drivers/net/caif/Kconfig
> > > > > @@ -58,8 +58,4 @@ config CAIF_VIRTIO
> > > > >    	---help---
> > > > >    	  The CAIF driver for CAIF over Virtio.
> > > > > -if CAIF_VIRTIO
> > > > > -source "drivers/vhost/Kconfig.vringh"
> > > > > -endif
> > > > > -
> > > > >    endif # CAIF_DRIVERS
> > > > > diff --git a/drivers/vhost/Kconfig b/drivers/vhost/Kconfig
> > > > > index 3d03ccbd1adc..4aef10a54cd1 100644
> > > > > --- a/drivers/vhost/Kconfig
> > > > > +++ b/drivers/vhost/Kconfig
> > > > > @@ -1,8 +1,20 @@
> > > > >    # SPDX-License-Identifier: GPL-2.0-only
> > > > > +config VHOST_RING
> > > > > +	tristate
> > > > > +	help
> > > > > +	  This option is selected by any driver which needs to access
> > > > > +	  the host side of a virtio ring.
> > > > > +
> > > > > +menuconfig VHOST
> > > > > +	tristate "Host kernel accelerator for virtio (VHOST)"
> > > > > +	help
> > > > > +	  This option is selected by any driver which needs to access
> > > > > +	  the core of vhost.
> > > > > +if VHOST
> > > > > +
> > > > The description here is wrong, isn't it?
> > > > VHOST and VHOST_RING are no longer selected, right?
> > > 
> > > For VHOST not currently.
> > Can we just bring it back and select it?
> 
> 
> Right, so if bring it back, we don't even need the stub.
> 
> How about something like attached?
> 
> Thanks
> 
> 
> > 
> > > For VHOST_RING, it was selected by CAIF, VOP and VDPASIM.
> > > 
> > > Thanks
> > > 
> > > 
> > > > 
> > > > >    config VHOST_NET
> > > > >    	tristate "Host kernel accelerator for virtio net"
> > > > >    	depends on NET && EVENTFD && (TUN || !TUN) && (TAP || !TAP)
> > > > > -	select VHOST
> > > > >    	---help---
> > > > >    	  This kernel module can be loaded in host kernel to accelerate
> > > > >    	  guest networking with virtio_net. Not to be confused with virtio_net
> > > > > @@ -14,7 +26,6 @@ config VHOST_NET
> > > > >    config VHOST_SCSI
> > > > >    	tristate "VHOST_SCSI TCM fabric driver"
> > > > >    	depends on TARGET_CORE && EVENTFD
> > > > > -	select VHOST
> > > > >    	default n
> > > > >    	---help---
> > > > >    	Say M here to enable the vhost_scsi TCM fabric module
> > > > > @@ -24,7 +35,6 @@ config VHOST_VSOCK
> > > > >    	tristate "vhost virtio-vsock driver"
> > > > >    	depends on VSOCKETS && EVENTFD
> > > > >    	select VIRTIO_VSOCKETS_COMMON
> > > > > -	select VHOST
> > > > >    	default n
> > > > >    	---help---
> > > > >    	This kernel module can be loaded in the host kernel to provide AF_VSOCK
> > > > > @@ -34,12 +44,6 @@ config VHOST_VSOCK
> > > > >    	To compile this driver as a module, choose M here: the module will be called
> > > > >    	vhost_vsock.
> > > > > -config VHOST
> > > > > -	tristate
> > > > > -	---help---
> > > > > -	  This option is selected by any driver which needs to access
> > > > > -	  the core of vhost.
> > > > > -
> > > > >    config VHOST_CROSS_ENDIAN_LEGACY
> > > > >    	bool "Cross-endian support for vhost"
> > > > >    	default n
> > > > > @@ -54,3 +58,4 @@ config VHOST_CROSS_ENDIAN_LEGACY
> > > > >    	  adds some overhead, it is disabled by default.
> > > > >    	  If unsure, say "N".
> > > > > +endif
> > > > > diff --git a/drivers/vhost/Kconfig.vringh b/drivers/vhost/Kconfig.vringh
> > > > > deleted file mode 100644
> > > > > index c1fe36a9b8d4..000000000000
> > > > > --- a/drivers/vhost/Kconfig.vringh
> > > > > +++ /dev/null
> > > > > @@ -1,6 +0,0 @@
> > > > > -# SPDX-License-Identifier: GPL-2.0-only
> > > > > -config VHOST_RING
> > > > > -	tristate
> > > > > -	---help---
> > > > > -	  This option is selected by any driver which needs to access
> > > > > -	  the host side of a virtio ring.
> > > > > -- 
> > > > > 2.20.1

> >From 9b3a5d23b8bf6b0a11e65e688335d782f8e6aa5c Mon Sep 17 00:00:00 2001
> From: Jason Wang <jasowang@redhat.com>
> Date: Wed, 1 Apr 2020 22:17:27 +0800
> Subject: [PATCH] vhost: let CONFIG_VHOST to be selected by drivers
> 
> The defconfig on some archs enable vhost_net or vhost_vsock by
> default. So instead of adding CONFIG_VHOST=m to all of those files,
> simply letting CONFIG_VHOST to be selected by all of the vhost
> drivers. This fixes the build on the archs with CONFIG_VHOST_NET=m in
> their defconfig.
> 
> Signed-off-by: Jason Wang <jasowang@redhat.com>
> ---
>  drivers/vhost/Kconfig | 15 +++++++++++----
>  1 file changed, 11 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/vhost/Kconfig b/drivers/vhost/Kconfig
> index 2523a1d4290a..362b832f5338 100644
> --- a/drivers/vhost/Kconfig
> +++ b/drivers/vhost/Kconfig
> @@ -11,19 +11,23 @@ config VHOST_RING
>  	  This option is selected by any driver which needs to access
>  	  the host side of a virtio ring.
>  
> -menuconfig VHOST
> -	tristate "Host kernel accelerator for virtio (VHOST)"
> -	depends on EVENTFD
> +config VHOST
> +	tristate
>  	select VHOST_IOTLB
>  	help
>  	  This option is selected by any driver which needs to access
>  	  the core of vhost.
>  
> -if VHOST
> +menuconfig VHOST_MENU
> +	bool "VHOST drivers"
> +	default y
> +
> +if VHOST_MENU

In fact this is similar to VIRTIO, and I wonder whether VIRTIO has also
been broken by
	commit 7b95fec6d2ffa53f4a8d637b0f223644d458ea4e
	Author: Vincent Legoll <vincent.legoll@gmail.com>
	Date:   Sun Jan 7 12:33:56 2018 +0100

	    virtio: make VIRTIO a menuconfig to ease disabling it all

I see lots of defconfigs set VIRTIO_PCI but not VIRTIO_MENU ...



-- 
MST


^ permalink raw reply	[flat|nested] 38+ messages in thread

* Re: [PATCH V9 1/9] vhost: refine vhost and vringh kconfig
  2020-04-01 14:35           ` Michael S. Tsirkin
@ 2020-04-01 14:39             ` Jason Wang
  0 siblings, 0 replies; 38+ messages in thread
From: Jason Wang @ 2020-04-01 14:39 UTC (permalink / raw)
  To: Michael S. Tsirkin
  Cc: linux-kernel, kvm, virtualization, netdev, jgg, maxime.coquelin,
	cunming.liang, zhihong.wang, rob.miller, xiao.w.wang,
	lingshan.zhu, eperezma, lulu, parav, kevin.tian, stefanha,
	rdunlap, hch, aadam, jiri, shahafs, hanand, mhabets, gdawar,
	saugatm, vmireyno, zhangweining


On 2020/4/1 下午10:35, Michael S. Tsirkin wrote:
>> diff --git a/drivers/vhost/Kconfig b/drivers/vhost/Kconfig
>> index 2523a1d4290a..362b832f5338 100644
>> --- a/drivers/vhost/Kconfig
>> +++ b/drivers/vhost/Kconfig
>> @@ -11,19 +11,23 @@ config VHOST_RING
>>   	  This option is selected by any driver which needs to access
>>   	  the host side of a virtio ring.
>>   
>> -menuconfig VHOST
>> -	tristate "Host kernel accelerator for virtio (VHOST)"
>> -	depends on EVENTFD
>> +config VHOST
>> +	tristate
>>   	select VHOST_IOTLB
>>   	help
>>   	  This option is selected by any driver which needs to access
>>   	  the core of vhost.
>>   
>> -if VHOST
>> +menuconfig VHOST_MENU
>> +	bool "VHOST drivers"
>> +	default y
>> +
>> +if VHOST_MENU
> Will this not still have the problem with defconfigs? They don't set
> VHOST_MENU ...


Looks not, since it was enabled by default.

I tested this on s390/ppc defconfigs:

# make ARCH=s390 defconfig
*** Default configuration is based on 'defconfig'
#
# No change to .config
#
# grep CONFIG_VHOST .config
CONFIG_VHOST_IOTLB=m
CONFIG_VHOST=m
CONFIG_VHOST_MENU=y
CONFIG_VHOST_NET=m
CONFIG_VHOST_VSOCK=m
# CONFIG_VHOST_VDPA is not set
# CONFIG_VHOST_CROSS_ENDIAN_LEGACY is not set

Thanks


^ permalink raw reply	[flat|nested] 38+ messages in thread

* Re: [PATCH V9 1/9] vhost: refine vhost and vringh kconfig
  2020-04-01 14:39           ` Michael S. Tsirkin
@ 2020-04-01 14:43             ` Jason Wang
  0 siblings, 0 replies; 38+ messages in thread
From: Jason Wang @ 2020-04-01 14:43 UTC (permalink / raw)
  To: Michael S. Tsirkin
  Cc: linux-kernel, kvm, virtualization, netdev, jgg, maxime.coquelin,
	cunming.liang, zhihong.wang, rob.miller, xiao.w.wang,
	lingshan.zhu, eperezma, lulu, parav, kevin.tian, stefanha,
	rdunlap, hch, aadam, jiri, shahafs, hanand, mhabets, gdawar,
	saugatm, vmireyno, zhangweining


On 2020/4/1 下午10:39, Michael S. Tsirkin wrote:
>> >From 9b3a5d23b8bf6b0a11e65e688335d782f8e6aa5c Mon Sep 17 00:00:00 2001
>> From: Jason Wang<jasowang@redhat.com>
>> Date: Wed, 1 Apr 2020 22:17:27 +0800
>> Subject: [PATCH] vhost: let CONFIG_VHOST to be selected by drivers
>>
>> The defconfig on some archs enable vhost_net or vhost_vsock by
>> default. So instead of adding CONFIG_VHOST=m to all of those files,
>> simply letting CONFIG_VHOST to be selected by all of the vhost
>> drivers. This fixes the build on the archs with CONFIG_VHOST_NET=m in
>> their defconfig.
>>
>> Signed-off-by: Jason Wang<jasowang@redhat.com>
>> ---
>>   drivers/vhost/Kconfig | 15 +++++++++++----
>>   1 file changed, 11 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/vhost/Kconfig b/drivers/vhost/Kconfig
>> index 2523a1d4290a..362b832f5338 100644
>> --- a/drivers/vhost/Kconfig
>> +++ b/drivers/vhost/Kconfig
>> @@ -11,19 +11,23 @@ config VHOST_RING
>>   	  This option is selected by any driver which needs to access
>>   	  the host side of a virtio ring.
>>   
>> -menuconfig VHOST
>> -	tristate "Host kernel accelerator for virtio (VHOST)"
>> -	depends on EVENTFD
>> +config VHOST
>> +	tristate
>>   	select VHOST_IOTLB
>>   	help
>>   	  This option is selected by any driver which needs to access
>>   	  the core of vhost.
>>   
>> -if VHOST
>> +menuconfig VHOST_MENU
>> +	bool "VHOST drivers"
>> +	default y
>> +
>> +if VHOST_MENU
> In fact this is similar to VIRTIO, and I wonder whether VIRTIO has also
> been broken by
> 	commit 7b95fec6d2ffa53f4a8d637b0f223644d458ea4e
> 	Author: Vincent Legoll<vincent.legoll@gmail.com>
> 	Date:   Sun Jan 7 12:33:56 2018 +0100
>
> 	    virtio: make VIRTIO a menuconfig to ease disabling it all
>
> I see lots of defconfigs set VIRTIO_PCI but not VIRTIO_MENU ...


Probably not since VIRTIO_MENU has "default y"

E.g for powerpc, I got:

# make ARCH=powerpc defconfig
*** Default configuration is based on 'ppc64_defconfig'
#
# No change to .config
#
# grep CONFIG_VIRTIO .config
CONFIG_VIRTIO_BLK=m
CONFIG_VIRTIO_NET=m
CONFIG_VIRTIO_CONSOLE=m
CONFIG_VIRTIO=m
CONFIG_VIRTIO_MENU=y
CONFIG_VIRTIO_PCI=m
CONFIG_VIRTIO_PCI_LEGACY=y
# CONFIG_VIRTIO_VDPA is not set
CONFIG_VIRTIO_BALLOON=m
# CONFIG_VIRTIO_INPUT is not set
# CONFIG_VIRTIO_MMIO is not set
# CONFIG_VIRTIO_FS is not set

Thanks


^ permalink raw reply	[flat|nested] 38+ messages in thread

* Re: [PATCH V9 1/9] vhost: refine vhost and vringh kconfig
  2020-04-01 14:27             ` Michael S. Tsirkin
@ 2020-04-01 14:50               ` Jason Wang
  2020-04-01 15:57                 ` Michael S. Tsirkin
  0 siblings, 1 reply; 38+ messages in thread
From: Jason Wang @ 2020-04-01 14:50 UTC (permalink / raw)
  To: Michael S. Tsirkin
  Cc: Christian Borntraeger, linux-kernel, kvm, virtualization, netdev,
	jgg, maxime.coquelin, cunming.liang, zhihong.wang, rob.miller,
	xiao.w.wang, lingshan.zhu, eperezma, lulu, parav, kevin.tian,
	stefanha, rdunlap, hch, aadam, jiri, shahafs, hanand, mhabets,
	gdawar, saugatm, vmireyno, zhangweining


On 2020/4/1 下午10:27, Michael S. Tsirkin wrote:
> On Wed, Apr 01, 2020 at 10:13:29PM +0800, Jason Wang wrote:
>> On 2020/4/1 下午9:02, Christian Borntraeger wrote:
>>> On 01.04.20 14:56, Christian Borntraeger wrote:
>>>> On 01.04.20 14:50, Jason Wang wrote:
>>>>> On 2020/4/1 下午7:21, Christian Borntraeger wrote:
>>>>>> On 26.03.20 15:01, Jason Wang wrote:
>>>>>>> Currently, CONFIG_VHOST depends on CONFIG_VIRTUALIZATION. But vhost is
>>>>>>> not necessarily for VM since it's a generic userspace and kernel
>>>>>>> communication protocol. Such dependency may prevent archs without
>>>>>>> virtualization support from using vhost.
>>>>>>>
>>>>>>> To solve this, a dedicated vhost menu is created under drivers so
>>>>>>> CONIFG_VHOST can be decoupled out of CONFIG_VIRTUALIZATION.
>>>>>> FWIW, this now results in vhost not being build with defconfig kernels (in todays
>>>>>> linux-next).
>>>>>>
>>>>> Hi Christian:
>>>>>
>>>>> Did you meet it even with this commit https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?id=a4be40cbcedba9b5b714f3c95182e8a45176e42d?
>>>> I simply used linux-next. The defconfig does NOT contain CONFIG_VHOST and therefore CONFIG_VHOST_NET and friends
>>>> can not be selected.
>>>>
>>>> $ git checkout next-20200401
>>>> $ make defconfig
>>>>     HOSTCC  scripts/basic/fixdep
>>>>     HOSTCC  scripts/kconfig/conf.o
>>>>     HOSTCC  scripts/kconfig/confdata.o
>>>>     HOSTCC  scripts/kconfig/expr.o
>>>>     LEX     scripts/kconfig/lexer.lex.c
>>>>     YACC    scripts/kconfig/parser.tab.[ch]
>>>>     HOSTCC  scripts/kconfig/lexer.lex.o
>>>>     HOSTCC  scripts/kconfig/parser.tab.o
>>>>     HOSTCC  scripts/kconfig/preprocess.o
>>>>     HOSTCC  scripts/kconfig/symbol.o
>>>>     HOSTCC  scripts/kconfig/util.o
>>>>     HOSTLD  scripts/kconfig/conf
>>>> *** Default configuration is based on 'x86_64_defconfig'
>>>> #
>>>> # configuration written to .config
>>>> #
>>>>
>>>> $ grep VHOST .config
>>>> # CONFIG_VHOST is not set
>>>>
>>>>> If yes, what's your build config looks like?
>>>>>
>>>>> Thanks
>>> This was x86. Not sure if that did work before.
>>> On s390 this is definitely a regression as the defconfig files
>>> for s390 do select VHOST_NET
>>>
>>> grep VHOST arch/s390/configs/*
>>> arch/s390/configs/debug_defconfig:CONFIG_VHOST_NET=m
>>> arch/s390/configs/debug_defconfig:CONFIG_VHOST_VSOCK=m
>>> arch/s390/configs/defconfig:CONFIG_VHOST_NET=m
>>> arch/s390/configs/defconfig:CONFIG_VHOST_VSOCK=m
>>>
>>> and this worked with 5.6, but does not work with next. Just adding
>>> CONFIG_VHOST=m to the defconfig solves the issue, something like
>>
>> Right, I think we probably need
>>
>> 1) add CONFIG_VHOST=m to all defconfigs that enables
>> CONFIG_VHOST_NET/VSOCK/SCSI.
>>
>> or
>>
>> 2) don't use menuconfig for CONFIG_VHOST, let NET/SCSI/VDPA just select it.
>>
>> Thanks
> OK I tried this:
>
> diff --git a/drivers/vhost/Kconfig b/drivers/vhost/Kconfig
> index 2523a1d4290a..a314b900d479 100644
> --- a/drivers/vhost/Kconfig
> +++ b/drivers/vhost/Kconfig
> @@ -19,11 +19,10 @@ menuconfig VHOST
>   	  This option is selected by any driver which needs to access
>   	  the core of vhost.
>   
> -if VHOST
> -
>   config VHOST_NET
>   	tristate "Host kernel accelerator for virtio net"
>   	depends on NET && EVENTFD && (TUN || !TUN) && (TAP || !TAP)
> +	select VHOST
>   	---help---
>   	  This kernel module can be loaded in host kernel to accelerate
>   	  guest networking with virtio_net. Not to be confused with virtio_net
> @@ -35,6 +34,7 @@ config VHOST_NET
>   config VHOST_SCSI
>   	tristate "VHOST_SCSI TCM fabric driver"
>   	depends on TARGET_CORE && EVENTFD
> +	select VHOST
>   	default n
>   	---help---
>   	Say M here to enable the vhost_scsi TCM fabric module
> @@ -44,6 +44,7 @@ config VHOST_VSOCK
>   	tristate "vhost virtio-vsock driver"
>   	depends on VSOCKETS && EVENTFD
>   	select VIRTIO_VSOCKETS_COMMON
> +	select VHOST
>   	default n
>   	---help---
>   	This kernel module can be loaded in the host kernel to provide AF_VSOCK
> @@ -57,6 +58,7 @@ config VHOST_VDPA
>   	tristate "Vhost driver for vDPA-based backend"
>   	depends on EVENTFD
>   	select VDPA
> +	select VHOST
>   	help
>   	  This kernel module can be loaded in host kernel to accelerate
>   	  guest virtio devices with the vDPA-based backends.
> @@ -78,5 +80,3 @@ config VHOST_CROSS_ENDIAN_LEGACY
>   	  adds some overhead, it is disabled by default.
>   
>   	  If unsure, say "N".
> -
> -endif
>
>
> But now CONFIG_VHOST is always "y", never "m".
> Which I think will make it a built-in.
> Didn't figure out why yet.


Is it because the dependency of EVENTFD for CONFIG_VHOST?

Remove that one for this patch, I can get CONFIG_VHOST=m.

But according to documentation/kbuild/kconfig.rst, select is used for 
option without prompt.

Thanks


>


^ permalink raw reply	[flat|nested] 38+ messages in thread

* Re: [PATCH V9 1/9] vhost: refine vhost and vringh kconfig
  2020-04-01 14:50               ` Jason Wang
@ 2020-04-01 15:57                 ` Michael S. Tsirkin
  2020-04-01 18:53                   ` Christian Borntraeger
  0 siblings, 1 reply; 38+ messages in thread
From: Michael S. Tsirkin @ 2020-04-01 15:57 UTC (permalink / raw)
  To: Jason Wang
  Cc: Christian Borntraeger, linux-kernel, kvm, virtualization, netdev,
	jgg, maxime.coquelin, cunming.liang, zhihong.wang, rob.miller,
	xiao.w.wang, lingshan.zhu, eperezma, lulu, parav, kevin.tian,
	stefanha, rdunlap, hch, aadam, jiri, shahafs, hanand, mhabets,
	gdawar, saugatm, vmireyno, zhangweining

On Wed, Apr 01, 2020 at 10:50:50PM +0800, Jason Wang wrote:
> 
> On 2020/4/1 下午10:27, Michael S. Tsirkin wrote:
> > On Wed, Apr 01, 2020 at 10:13:29PM +0800, Jason Wang wrote:
> > > On 2020/4/1 下午9:02, Christian Borntraeger wrote:
> > > > On 01.04.20 14:56, Christian Borntraeger wrote:
> > > > > On 01.04.20 14:50, Jason Wang wrote:
> > > > > > On 2020/4/1 下午7:21, Christian Borntraeger wrote:
> > > > > > > On 26.03.20 15:01, Jason Wang wrote:
> > > > > > > > Currently, CONFIG_VHOST depends on CONFIG_VIRTUALIZATION. But vhost is
> > > > > > > > not necessarily for VM since it's a generic userspace and kernel
> > > > > > > > communication protocol. Such dependency may prevent archs without
> > > > > > > > virtualization support from using vhost.
> > > > > > > > 
> > > > > > > > To solve this, a dedicated vhost menu is created under drivers so
> > > > > > > > CONIFG_VHOST can be decoupled out of CONFIG_VIRTUALIZATION.
> > > > > > > FWIW, this now results in vhost not being build with defconfig kernels (in todays
> > > > > > > linux-next).
> > > > > > > 
> > > > > > Hi Christian:
> > > > > > 
> > > > > > Did you meet it even with this commit https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?id=a4be40cbcedba9b5b714f3c95182e8a45176e42d?
> > > > > I simply used linux-next. The defconfig does NOT contain CONFIG_VHOST and therefore CONFIG_VHOST_NET and friends
> > > > > can not be selected.
> > > > > 
> > > > > $ git checkout next-20200401
> > > > > $ make defconfig
> > > > >     HOSTCC  scripts/basic/fixdep
> > > > >     HOSTCC  scripts/kconfig/conf.o
> > > > >     HOSTCC  scripts/kconfig/confdata.o
> > > > >     HOSTCC  scripts/kconfig/expr.o
> > > > >     LEX     scripts/kconfig/lexer.lex.c
> > > > >     YACC    scripts/kconfig/parser.tab.[ch]
> > > > >     HOSTCC  scripts/kconfig/lexer.lex.o
> > > > >     HOSTCC  scripts/kconfig/parser.tab.o
> > > > >     HOSTCC  scripts/kconfig/preprocess.o
> > > > >     HOSTCC  scripts/kconfig/symbol.o
> > > > >     HOSTCC  scripts/kconfig/util.o
> > > > >     HOSTLD  scripts/kconfig/conf
> > > > > *** Default configuration is based on 'x86_64_defconfig'
> > > > > #
> > > > > # configuration written to .config
> > > > > #
> > > > > 
> > > > > $ grep VHOST .config
> > > > > # CONFIG_VHOST is not set
> > > > > 
> > > > > > If yes, what's your build config looks like?
> > > > > > 
> > > > > > Thanks
> > > > This was x86. Not sure if that did work before.
> > > > On s390 this is definitely a regression as the defconfig files
> > > > for s390 do select VHOST_NET
> > > > 
> > > > grep VHOST arch/s390/configs/*
> > > > arch/s390/configs/debug_defconfig:CONFIG_VHOST_NET=m
> > > > arch/s390/configs/debug_defconfig:CONFIG_VHOST_VSOCK=m
> > > > arch/s390/configs/defconfig:CONFIG_VHOST_NET=m
> > > > arch/s390/configs/defconfig:CONFIG_VHOST_VSOCK=m
> > > > 
> > > > and this worked with 5.6, but does not work with next. Just adding
> > > > CONFIG_VHOST=m to the defconfig solves the issue, something like
> > > 
> > > Right, I think we probably need
> > > 
> > > 1) add CONFIG_VHOST=m to all defconfigs that enables
> > > CONFIG_VHOST_NET/VSOCK/SCSI.
> > > 
> > > or
> > > 
> > > 2) don't use menuconfig for CONFIG_VHOST, let NET/SCSI/VDPA just select it.
> > > 
> > > Thanks
> > OK I tried this:
> > 
> > diff --git a/drivers/vhost/Kconfig b/drivers/vhost/Kconfig
> > index 2523a1d4290a..a314b900d479 100644
> > --- a/drivers/vhost/Kconfig
> > +++ b/drivers/vhost/Kconfig
> > @@ -19,11 +19,10 @@ menuconfig VHOST
> >   	  This option is selected by any driver which needs to access
> >   	  the core of vhost.
> > -if VHOST
> > -
> >   config VHOST_NET
> >   	tristate "Host kernel accelerator for virtio net"
> >   	depends on NET && EVENTFD && (TUN || !TUN) && (TAP || !TAP)
> > +	select VHOST
> >   	---help---
> >   	  This kernel module can be loaded in host kernel to accelerate
> >   	  guest networking with virtio_net. Not to be confused with virtio_net
> > @@ -35,6 +34,7 @@ config VHOST_NET
> >   config VHOST_SCSI
> >   	tristate "VHOST_SCSI TCM fabric driver"
> >   	depends on TARGET_CORE && EVENTFD
> > +	select VHOST
> >   	default n
> >   	---help---
> >   	Say M here to enable the vhost_scsi TCM fabric module
> > @@ -44,6 +44,7 @@ config VHOST_VSOCK
> >   	tristate "vhost virtio-vsock driver"
> >   	depends on VSOCKETS && EVENTFD
> >   	select VIRTIO_VSOCKETS_COMMON
> > +	select VHOST
> >   	default n
> >   	---help---
> >   	This kernel module can be loaded in the host kernel to provide AF_VSOCK
> > @@ -57,6 +58,7 @@ config VHOST_VDPA
> >   	tristate "Vhost driver for vDPA-based backend"
> >   	depends on EVENTFD
> >   	select VDPA
> > +	select VHOST
> >   	help
> >   	  This kernel module can be loaded in host kernel to accelerate
> >   	  guest virtio devices with the vDPA-based backends.
> > @@ -78,5 +80,3 @@ config VHOST_CROSS_ENDIAN_LEGACY
> >   	  adds some overhead, it is disabled by default.
> >   	  If unsure, say "N".
> > -
> > -endif
> > 
> > 
> > But now CONFIG_VHOST is always "y", never "m".
> > Which I think will make it a built-in.
> > Didn't figure out why yet.
> 
> 
> Is it because the dependency of EVENTFD for CONFIG_VHOST?

Oh no, it's because I forgot to change menuconfig to config.


> Remove that one for this patch, I can get CONFIG_VHOST=m.
> 
> But according to documentation/kbuild/kconfig.rst, select is used for option
> without prompt.
> 
> Thanks
> 
> 
> > 


^ permalink raw reply	[flat|nested] 38+ messages in thread

* Re: [PATCH V9 1/9] vhost: refine vhost and vringh kconfig
  2020-04-01 14:29         ` Jason Wang
  2020-04-01 14:35           ` Michael S. Tsirkin
  2020-04-01 14:39           ` Michael S. Tsirkin
@ 2020-04-01 16:05           ` Michael S. Tsirkin
  2020-04-01 16:08           ` Michael S. Tsirkin
  3 siblings, 0 replies; 38+ messages in thread
From: Michael S. Tsirkin @ 2020-04-01 16:05 UTC (permalink / raw)
  To: Jason Wang
  Cc: linux-kernel, kvm, virtualization, netdev, jgg, maxime.coquelin,
	cunming.liang, zhihong.wang, rob.miller, xiao.w.wang,
	lingshan.zhu, eperezma, lulu, parav, kevin.tian, stefanha,
	rdunlap, hch, aadam, jiri, shahafs, hanand, mhabets, gdawar,
	saugatm, vmireyno, zhangweining

On Wed, Apr 01, 2020 at 10:29:32PM +0800, Jason Wang wrote:
> >From 9b3a5d23b8bf6b0a11e65e688335d782f8e6aa5c Mon Sep 17 00:00:00 2001
> From: Jason Wang <jasowang@redhat.com>
> Date: Wed, 1 Apr 2020 22:17:27 +0800
> Subject: [PATCH] vhost: let CONFIG_VHOST to be selected by drivers
> 
> The defconfig on some archs enable vhost_net or vhost_vsock by
> default. So instead of adding CONFIG_VHOST=m to all of those files,
> simply letting CONFIG_VHOST to be selected by all of the vhost
> drivers. This fixes the build on the archs with CONFIG_VHOST_NET=m in
> their defconfig.
> 
> Signed-off-by: Jason Wang <jasowang@redhat.com>
> ---
>  drivers/vhost/Kconfig | 15 +++++++++++----
>  1 file changed, 11 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/vhost/Kconfig b/drivers/vhost/Kconfig
> index 2523a1d4290a..362b832f5338 100644
> --- a/drivers/vhost/Kconfig
> +++ b/drivers/vhost/Kconfig
> @@ -11,19 +11,23 @@ config VHOST_RING
>  	  This option is selected by any driver which needs to access
>  	  the host side of a virtio ring.
>  
> -menuconfig VHOST
> -	tristate "Host kernel accelerator for virtio (VHOST)"
> -	depends on EVENTFD
> +config VHOST
> +	tristate
>  	select VHOST_IOTLB
>  	help
>  	  This option is selected by any driver which needs to access
>  	  the core of vhost.


OK so don't we need the dependency on EVENTFD though?
I recall there was a bug this was supposed to fix ...


> -if VHOST
> +menuconfig VHOST_MENU
> +	bool "VHOST drivers"
> +	default y
> +
> +if VHOST_MENU
>  
>  config VHOST_NET
>  	tristate "Host kernel accelerator for virtio net"
>  	depends on NET && EVENTFD && (TUN || !TUN) && (TAP || !TAP)
> +	select VHOST
>  	---help---
>  	  This kernel module can be loaded in host kernel to accelerate
>  	  guest networking with virtio_net. Not to be confused with virtio_net
> @@ -35,6 +39,7 @@ config VHOST_NET
>  config VHOST_SCSI
>  	tristate "VHOST_SCSI TCM fabric driver"
>  	depends on TARGET_CORE && EVENTFD
> +	select VHOST
>  	default n
>  	---help---
>  	Say M here to enable the vhost_scsi TCM fabric module
> @@ -43,6 +48,7 @@ config VHOST_SCSI
>  config VHOST_VSOCK
>  	tristate "vhost virtio-vsock driver"
>  	depends on VSOCKETS && EVENTFD
> +	select VHOST
>  	select VIRTIO_VSOCKETS_COMMON
>  	default n
>  	---help---
> @@ -56,6 +62,7 @@ config VHOST_VSOCK
>  config VHOST_VDPA
>  	tristate "Vhost driver for vDPA-based backend"
>  	depends on EVENTFD
> +	select VHOST
>  	select VDPA
>  	help
>  	  This kernel module can be loaded in host kernel to accelerate
> -- 
> 2.20.1
> 


^ permalink raw reply	[flat|nested] 38+ messages in thread

* Re: [PATCH V9 1/9] vhost: refine vhost and vringh kconfig
  2020-04-01 14:29         ` Jason Wang
                             ` (2 preceding siblings ...)
  2020-04-01 16:05           ` Michael S. Tsirkin
@ 2020-04-01 16:08           ` Michael S. Tsirkin
  2020-04-02  3:22             ` Jason Wang
  3 siblings, 1 reply; 38+ messages in thread
From: Michael S. Tsirkin @ 2020-04-01 16:08 UTC (permalink / raw)
  To: Jason Wang
  Cc: linux-kernel, kvm, virtualization, netdev, jgg, maxime.coquelin,
	cunming.liang, zhihong.wang, rob.miller, xiao.w.wang,
	lingshan.zhu, eperezma, lulu, parav, kevin.tian, stefanha,
	rdunlap, hch, aadam, jiri, shahafs, hanand, mhabets, gdawar,
	saugatm, vmireyno, zhangweining

On Wed, Apr 01, 2020 at 10:29:32PM +0800, Jason Wang wrote:
> >From 9b3a5d23b8bf6b0a11e65e688335d782f8e6aa5c Mon Sep 17 00:00:00 2001
> From: Jason Wang <jasowang@redhat.com>
> Date: Wed, 1 Apr 2020 22:17:27 +0800
> Subject: [PATCH] vhost: let CONFIG_VHOST to be selected by drivers
> 
> The defconfig on some archs enable vhost_net or vhost_vsock by
> default. So instead of adding CONFIG_VHOST=m to all of those files,
> simply letting CONFIG_VHOST to be selected by all of the vhost
> drivers. This fixes the build on the archs with CONFIG_VHOST_NET=m in
> their defconfig.
> 
> Signed-off-by: Jason Wang <jasowang@redhat.com>
> ---
>  drivers/vhost/Kconfig | 15 +++++++++++----
>  1 file changed, 11 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/vhost/Kconfig b/drivers/vhost/Kconfig
> index 2523a1d4290a..362b832f5338 100644
> --- a/drivers/vhost/Kconfig
> +++ b/drivers/vhost/Kconfig
> @@ -11,19 +11,23 @@ config VHOST_RING
>  	  This option is selected by any driver which needs to access
>  	  the host side of a virtio ring.
>  
> -menuconfig VHOST
> -	tristate "Host kernel accelerator for virtio (VHOST)"
> -	depends on EVENTFD
> +config VHOST
> +	tristate
>  	select VHOST_IOTLB
>  	help
>  	  This option is selected by any driver which needs to access
>  	  the core of vhost.
>  
> -if VHOST
> +menuconfig VHOST_MENU
> +	bool "VHOST drivers"
> +	default y
> +
> +if VHOST_MENU
>  
>  config VHOST_NET
>  	tristate "Host kernel accelerator for virtio net"
>  	depends on NET && EVENTFD && (TUN || !TUN) && (TAP || !TAP)
> +	select VHOST
>  	---help---
>  	  This kernel module can be loaded in host kernel to accelerate
>  	  guest networking with virtio_net. Not to be confused with virtio_net
> @@ -35,6 +39,7 @@ config VHOST_NET
>  config VHOST_SCSI
>  	tristate "VHOST_SCSI TCM fabric driver"
>  	depends on TARGET_CORE && EVENTFD
> +	select VHOST
>  	default n
>  	---help---
>  	Say M here to enable the vhost_scsi TCM fabric module
> @@ -43,6 +48,7 @@ config VHOST_SCSI
>  config VHOST_VSOCK
>  	tristate "vhost virtio-vsock driver"
>  	depends on VSOCKETS && EVENTFD
> +	select VHOST
>  	select VIRTIO_VSOCKETS_COMMON
>  	default n
>  	---help---
> @@ -56,6 +62,7 @@ config VHOST_VSOCK
>  config VHOST_VDPA
>  	tristate "Vhost driver for vDPA-based backend"
>  	depends on EVENTFD
> +	select VHOST
>  	select VDPA
>  	help
>  	  This kernel module can be loaded in host kernel to accelerate

OK so I squashed this into the original buggy patch.
Could you please play with vhost branch of my tree on various
arches? If it looks ok to you let me know I'll push
this to next.


-- 
MST


^ permalink raw reply	[flat|nested] 38+ messages in thread

* Re: [PATCH V9 1/9] vhost: refine vhost and vringh kconfig
  2020-04-01 15:57                 ` Michael S. Tsirkin
@ 2020-04-01 18:53                   ` Christian Borntraeger
  0 siblings, 0 replies; 38+ messages in thread
From: Christian Borntraeger @ 2020-04-01 18:53 UTC (permalink / raw)
  To: Michael S. Tsirkin, Jason Wang
  Cc: linux-kernel, kvm, virtualization, netdev, jgg, maxime.coquelin,
	cunming.liang, zhihong.wang, rob.miller, xiao.w.wang,
	lingshan.zhu, eperezma, lulu, parav, kevin.tian, stefanha,
	rdunlap, hch, aadam, jiri, shahafs, hanand, mhabets, gdawar,
	saugatm, vmireyno, zhangweining



On 01.04.20 17:57, Michael S. Tsirkin wrote:
> On Wed, Apr 01, 2020 at 10:50:50PM +0800, Jason Wang wrote:
>>
>> On 2020/4/1 下午10:27, Michael S. Tsirkin wrote:
>>> On Wed, Apr 01, 2020 at 10:13:29PM +0800, Jason Wang wrote:
>>>> On 2020/4/1 下午9:02, Christian Borntraeger wrote:
>>>>> On 01.04.20 14:56, Christian Borntraeger wrote:
>>>>>> On 01.04.20 14:50, Jason Wang wrote:
>>>>>>> On 2020/4/1 下午7:21, Christian Borntraeger wrote:
>>>>>>>> On 26.03.20 15:01, Jason Wang wrote:
>>>>>>>>> Currently, CONFIG_VHOST depends on CONFIG_VIRTUALIZATION. But vhost is
>>>>>>>>> not necessarily for VM since it's a generic userspace and kernel
>>>>>>>>> communication protocol. Such dependency may prevent archs without
>>>>>>>>> virtualization support from using vhost.
>>>>>>>>>
>>>>>>>>> To solve this, a dedicated vhost menu is created under drivers so
>>>>>>>>> CONIFG_VHOST can be decoupled out of CONFIG_VIRTUALIZATION.
>>>>>>>> FWIW, this now results in vhost not being build with defconfig kernels (in todays
>>>>>>>> linux-next).
>>>>>>>>
>>>>>>> Hi Christian:
>>>>>>>
>>>>>>> Did you meet it even with this commit https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?id=a4be40cbcedba9b5b714f3c95182e8a45176e42d?
>>>>>> I simply used linux-next. The defconfig does NOT contain CONFIG_VHOST and therefore CONFIG_VHOST_NET and friends
>>>>>> can not be selected.
>>>>>>
>>>>>> $ git checkout next-20200401
>>>>>> $ make defconfig
>>>>>>     HOSTCC  scripts/basic/fixdep
>>>>>>     HOSTCC  scripts/kconfig/conf.o
>>>>>>     HOSTCC  scripts/kconfig/confdata.o
>>>>>>     HOSTCC  scripts/kconfig/expr.o
>>>>>>     LEX     scripts/kconfig/lexer.lex.c
>>>>>>     YACC    scripts/kconfig/parser.tab.[ch]
>>>>>>     HOSTCC  scripts/kconfig/lexer.lex.o
>>>>>>     HOSTCC  scripts/kconfig/parser.tab.o
>>>>>>     HOSTCC  scripts/kconfig/preprocess.o
>>>>>>     HOSTCC  scripts/kconfig/symbol.o
>>>>>>     HOSTCC  scripts/kconfig/util.o
>>>>>>     HOSTLD  scripts/kconfig/conf
>>>>>> *** Default configuration is based on 'x86_64_defconfig'
>>>>>> #
>>>>>> # configuration written to .config
>>>>>> #
>>>>>>
>>>>>> $ grep VHOST .config
>>>>>> # CONFIG_VHOST is not set
>>>>>>
>>>>>>> If yes, what's your build config looks like?
>>>>>>>
>>>>>>> Thanks
>>>>> This was x86. Not sure if that did work before.
>>>>> On s390 this is definitely a regression as the defconfig files
>>>>> for s390 do select VHOST_NET
>>>>>
>>>>> grep VHOST arch/s390/configs/*
>>>>> arch/s390/configs/debug_defconfig:CONFIG_VHOST_NET=m
>>>>> arch/s390/configs/debug_defconfig:CONFIG_VHOST_VSOCK=m
>>>>> arch/s390/configs/defconfig:CONFIG_VHOST_NET=m
>>>>> arch/s390/configs/defconfig:CONFIG_VHOST_VSOCK=m
>>>>>
>>>>> and this worked with 5.6, but does not work with next. Just adding
>>>>> CONFIG_VHOST=m to the defconfig solves the issue, something like
>>>>
>>>> Right, I think we probably need
>>>>
>>>> 1) add CONFIG_VHOST=m to all defconfigs that enables
>>>> CONFIG_VHOST_NET/VSOCK/SCSI.
>>>>
>>>> or
>>>>
>>>> 2) don't use menuconfig for CONFIG_VHOST, let NET/SCSI/VDPA just select it.
>>>>
>>>> Thanks
>>> OK I tried this:
>>>
>>> diff --git a/drivers/vhost/Kconfig b/drivers/vhost/Kconfig
>>> index 2523a1d4290a..a314b900d479 100644
>>> --- a/drivers/vhost/Kconfig
>>> +++ b/drivers/vhost/Kconfig
>>> @@ -19,11 +19,10 @@ menuconfig VHOST
>>>   	  This option is selected by any driver which needs to access
>>>   	  the core of vhost.
>>> -if VHOST
>>> -
>>>   config VHOST_NET
>>>   	tristate "Host kernel accelerator for virtio net"
>>>   	depends on NET && EVENTFD && (TUN || !TUN) && (TAP || !TAP)
>>> +	select VHOST
>>>   	---help---
>>>   	  This kernel module can be loaded in host kernel to accelerate
>>>   	  guest networking with virtio_net. Not to be confused with virtio_net
>>> @@ -35,6 +34,7 @@ config VHOST_NET
>>>   config VHOST_SCSI
>>>   	tristate "VHOST_SCSI TCM fabric driver"
>>>   	depends on TARGET_CORE && EVENTFD
>>> +	select VHOST
>>>   	default n
>>>   	---help---
>>>   	Say M here to enable the vhost_scsi TCM fabric module
>>> @@ -44,6 +44,7 @@ config VHOST_VSOCK
>>>   	tristate "vhost virtio-vsock driver"
>>>   	depends on VSOCKETS && EVENTFD
>>>   	select VIRTIO_VSOCKETS_COMMON
>>> +	select VHOST
>>>   	default n
>>>   	---help---
>>>   	This kernel module can be loaded in the host kernel to provide AF_VSOCK
>>> @@ -57,6 +58,7 @@ config VHOST_VDPA
>>>   	tristate "Vhost driver for vDPA-based backend"
>>>   	depends on EVENTFD
>>>   	select VDPA
>>> +	select VHOST
>>>   	help
>>>   	  This kernel module can be loaded in host kernel to accelerate
>>>   	  guest virtio devices with the vDPA-based backends.
>>> @@ -78,5 +80,3 @@ config VHOST_CROSS_ENDIAN_LEGACY
>>>   	  adds some overhead, it is disabled by default.
>>>   	  If unsure, say "N".
>>> -
>>> -endif
>>>
>>>
>>> But now CONFIG_VHOST is always "y", never "m".
>>> Which I think will make it a built-in.
>>> Didn't figure out why yet.
>>
>>
>> Is it because the dependency of EVENTFD for CONFIG_VHOST?
> 
> Oh no, it's because I forgot to change menuconfig to config.
> 
> 
>> Remove that one for this patch, I can get CONFIG_VHOST=m.

FWIW, the current vhost/linux-next branch seems to work again.


^ permalink raw reply	[flat|nested] 38+ messages in thread

* Re: [PATCH V9 1/9] vhost: refine vhost and vringh kconfig
  2020-04-01 16:08           ` Michael S. Tsirkin
@ 2020-04-02  3:22             ` Jason Wang
  2020-04-02 14:03               ` Michael S. Tsirkin
  0 siblings, 1 reply; 38+ messages in thread
From: Jason Wang @ 2020-04-02  3:22 UTC (permalink / raw)
  To: Michael S. Tsirkin
  Cc: linux-kernel, kvm, virtualization, netdev, jgg, maxime.coquelin,
	cunming.liang, zhihong.wang, rob.miller, xiao.w.wang,
	lingshan.zhu, eperezma, lulu, parav, kevin.tian, stefanha,
	rdunlap, hch, aadam, jiri, shahafs, hanand, mhabets, gdawar,
	saugatm, vmireyno, zhangweining


On 2020/4/2 上午12:08, Michael S. Tsirkin wrote:
> On Wed, Apr 01, 2020 at 10:29:32PM +0800, Jason Wang wrote:
>> >From 9b3a5d23b8bf6b0a11e65e688335d782f8e6aa5c Mon Sep 17 00:00:00 2001
>> From: Jason Wang <jasowang@redhat.com>
>> Date: Wed, 1 Apr 2020 22:17:27 +0800
>> Subject: [PATCH] vhost: let CONFIG_VHOST to be selected by drivers
>>
>> The defconfig on some archs enable vhost_net or vhost_vsock by
>> default. So instead of adding CONFIG_VHOST=m to all of those files,
>> simply letting CONFIG_VHOST to be selected by all of the vhost
>> drivers. This fixes the build on the archs with CONFIG_VHOST_NET=m in
>> their defconfig.
>>
>> Signed-off-by: Jason Wang <jasowang@redhat.com>
>> ---
>>   drivers/vhost/Kconfig | 15 +++++++++++----
>>   1 file changed, 11 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/vhost/Kconfig b/drivers/vhost/Kconfig
>> index 2523a1d4290a..362b832f5338 100644
>> --- a/drivers/vhost/Kconfig
>> +++ b/drivers/vhost/Kconfig
>> @@ -11,19 +11,23 @@ config VHOST_RING
>>   	  This option is selected by any driver which needs to access
>>   	  the host side of a virtio ring.
>>   
>> -menuconfig VHOST
>> -	tristate "Host kernel accelerator for virtio (VHOST)"
>> -	depends on EVENTFD
>> +config VHOST
>> +	tristate
>>   	select VHOST_IOTLB
>>   	help
>>   	  This option is selected by any driver which needs to access
>>   	  the core of vhost.
>>   
>> -if VHOST
>> +menuconfig VHOST_MENU
>> +	bool "VHOST drivers"
>> +	default y
>> +
>> +if VHOST_MENU
>>   
>>   config VHOST_NET
>>   	tristate "Host kernel accelerator for virtio net"
>>   	depends on NET && EVENTFD && (TUN || !TUN) && (TAP || !TAP)
>> +	select VHOST
>>   	---help---
>>   	  This kernel module can be loaded in host kernel to accelerate
>>   	  guest networking with virtio_net. Not to be confused with virtio_net
>> @@ -35,6 +39,7 @@ config VHOST_NET
>>   config VHOST_SCSI
>>   	tristate "VHOST_SCSI TCM fabric driver"
>>   	depends on TARGET_CORE && EVENTFD
>> +	select VHOST
>>   	default n
>>   	---help---
>>   	Say M here to enable the vhost_scsi TCM fabric module
>> @@ -43,6 +48,7 @@ config VHOST_SCSI
>>   config VHOST_VSOCK
>>   	tristate "vhost virtio-vsock driver"
>>   	depends on VSOCKETS && EVENTFD
>> +	select VHOST
>>   	select VIRTIO_VSOCKETS_COMMON
>>   	default n
>>   	---help---
>> @@ -56,6 +62,7 @@ config VHOST_VSOCK
>>   config VHOST_VDPA
>>   	tristate "Vhost driver for vDPA-based backend"
>>   	depends on EVENTFD
>> +	select VHOST


This part is not squashed.


>>   	select VDPA
>>   	help
>>   	  This kernel module can be loaded in host kernel to accelerate
> OK so I squashed this into the original buggy patch.
> Could you please play with vhost branch of my tree on various
> arches? If it looks ok to you let me know I'll push
> this to next.


With the above part squashed. I've tested all the archs whose defconfig 
have VHOST_NET or VHOST_VSOCK enabled.

All looks fine.

Thanks


^ permalink raw reply	[flat|nested] 38+ messages in thread

* Re: [PATCH V9 1/9] vhost: refine vhost and vringh kconfig
  2020-04-02  3:22             ` Jason Wang
@ 2020-04-02 14:03               ` Michael S. Tsirkin
  2020-04-02 14:23                 ` Jason Wang
  0 siblings, 1 reply; 38+ messages in thread
From: Michael S. Tsirkin @ 2020-04-02 14:03 UTC (permalink / raw)
  To: Jason Wang
  Cc: linux-kernel, kvm, virtualization, netdev, jgg, maxime.coquelin,
	cunming.liang, zhihong.wang, rob.miller, xiao.w.wang,
	lingshan.zhu, eperezma, lulu, parav, kevin.tian, stefanha,
	rdunlap, hch, aadam, jiri, shahafs, hanand, mhabets, gdawar,
	saugatm, vmireyno, zhangweining

On Thu, Apr 02, 2020 at 11:22:57AM +0800, Jason Wang wrote:
> 
> On 2020/4/2 上午12:08, Michael S. Tsirkin wrote:
> > On Wed, Apr 01, 2020 at 10:29:32PM +0800, Jason Wang wrote:
> > > >From 9b3a5d23b8bf6b0a11e65e688335d782f8e6aa5c Mon Sep 17 00:00:00 2001
> > > From: Jason Wang <jasowang@redhat.com>
> > > Date: Wed, 1 Apr 2020 22:17:27 +0800
> > > Subject: [PATCH] vhost: let CONFIG_VHOST to be selected by drivers
> > > 
> > > The defconfig on some archs enable vhost_net or vhost_vsock by
> > > default. So instead of adding CONFIG_VHOST=m to all of those files,
> > > simply letting CONFIG_VHOST to be selected by all of the vhost
> > > drivers. This fixes the build on the archs with CONFIG_VHOST_NET=m in
> > > their defconfig.
> > > 
> > > Signed-off-by: Jason Wang <jasowang@redhat.com>
> > > ---
> > >   drivers/vhost/Kconfig | 15 +++++++++++----
> > >   1 file changed, 11 insertions(+), 4 deletions(-)
> > > 
> > > diff --git a/drivers/vhost/Kconfig b/drivers/vhost/Kconfig
> > > index 2523a1d4290a..362b832f5338 100644
> > > --- a/drivers/vhost/Kconfig
> > > +++ b/drivers/vhost/Kconfig
> > > @@ -11,19 +11,23 @@ config VHOST_RING
> > >   	  This option is selected by any driver which needs to access
> > >   	  the host side of a virtio ring.
> > > -menuconfig VHOST
> > > -	tristate "Host kernel accelerator for virtio (VHOST)"
> > > -	depends on EVENTFD
> > > +config VHOST
> > > +	tristate
> > >   	select VHOST_IOTLB
> > >   	help
> > >   	  This option is selected by any driver which needs to access
> > >   	  the core of vhost.
> > > -if VHOST
> > > +menuconfig VHOST_MENU
> > > +	bool "VHOST drivers"
> > > +	default y
> > > +
> > > +if VHOST_MENU
> > >   config VHOST_NET
> > >   	tristate "Host kernel accelerator for virtio net"
> > >   	depends on NET && EVENTFD && (TUN || !TUN) && (TAP || !TAP)
> > > +	select VHOST
> > >   	---help---
> > >   	  This kernel module can be loaded in host kernel to accelerate
> > >   	  guest networking with virtio_net. Not to be confused with virtio_net
> > > @@ -35,6 +39,7 @@ config VHOST_NET
> > >   config VHOST_SCSI
> > >   	tristate "VHOST_SCSI TCM fabric driver"
> > >   	depends on TARGET_CORE && EVENTFD
> > > +	select VHOST
> > >   	default n
> > >   	---help---
> > >   	Say M here to enable the vhost_scsi TCM fabric module
> > > @@ -43,6 +48,7 @@ config VHOST_SCSI
> > >   config VHOST_VSOCK
> > >   	tristate "vhost virtio-vsock driver"
> > >   	depends on VSOCKETS && EVENTFD
> > > +	select VHOST
> > >   	select VIRTIO_VSOCKETS_COMMON
> > >   	default n
> > >   	---help---
> > > @@ -56,6 +62,7 @@ config VHOST_VSOCK
> > >   config VHOST_VDPA
> > >   	tristate "Vhost driver for vDPA-based backend"
> > >   	depends on EVENTFD
> > > +	select VHOST
> 
> 
> This part is not squashed.
> 
> 
> > >   	select VDPA
> > >   	help
> > >   	  This kernel module can be loaded in host kernel to accelerate
> > OK so I squashed this into the original buggy patch.
> > Could you please play with vhost branch of my tree on various
> > arches? If it looks ok to you let me know I'll push
> > this to next.
> 
> 
> With the above part squashed. I've tested all the archs whose defconfig have
> VHOST_NET or VHOST_VSOCK enabled.
> 
> All looks fine.
> 
> Thanks


I'm a bit confused. So is the next tag in my tree ok now?

-- 
MST


^ permalink raw reply	[flat|nested] 38+ messages in thread

* Re: [PATCH V9 1/9] vhost: refine vhost and vringh kconfig
  2020-04-02 14:03               ` Michael S. Tsirkin
@ 2020-04-02 14:23                 ` Jason Wang
  2020-04-02 14:38                   ` Michael S. Tsirkin
  0 siblings, 1 reply; 38+ messages in thread
From: Jason Wang @ 2020-04-02 14:23 UTC (permalink / raw)
  To: Michael S. Tsirkin
  Cc: linux-kernel, kvm, virtualization, netdev, jgg, maxime.coquelin,
	cunming.liang, zhihong.wang, rob.miller, xiao.w.wang,
	lingshan.zhu, eperezma, lulu, parav, kevin.tian, stefanha,
	rdunlap, hch, aadam, jiri, shahafs, hanand, mhabets, gdawar,
	saugatm, vmireyno, zhangweining


On 2020/4/2 下午10:03, Michael S. Tsirkin wrote:
> On Thu, Apr 02, 2020 at 11:22:57AM +0800, Jason Wang wrote:
>> On 2020/4/2 上午12:08, Michael S. Tsirkin wrote:
>>> On Wed, Apr 01, 2020 at 10:29:32PM +0800, Jason Wang wrote:
>>>> >From 9b3a5d23b8bf6b0a11e65e688335d782f8e6aa5c Mon Sep 17 00:00:00 2001
>>>> From: Jason Wang <jasowang@redhat.com>
>>>> Date: Wed, 1 Apr 2020 22:17:27 +0800
>>>> Subject: [PATCH] vhost: let CONFIG_VHOST to be selected by drivers
>>>>
>>>> The defconfig on some archs enable vhost_net or vhost_vsock by
>>>> default. So instead of adding CONFIG_VHOST=m to all of those files,
>>>> simply letting CONFIG_VHOST to be selected by all of the vhost
>>>> drivers. This fixes the build on the archs with CONFIG_VHOST_NET=m in
>>>> their defconfig.
>>>>
>>>> Signed-off-by: Jason Wang <jasowang@redhat.com>
>>>> ---
>>>>    drivers/vhost/Kconfig | 15 +++++++++++----
>>>>    1 file changed, 11 insertions(+), 4 deletions(-)
>>>>
>>>> diff --git a/drivers/vhost/Kconfig b/drivers/vhost/Kconfig
>>>> index 2523a1d4290a..362b832f5338 100644
>>>> --- a/drivers/vhost/Kconfig
>>>> +++ b/drivers/vhost/Kconfig
>>>> @@ -11,19 +11,23 @@ config VHOST_RING
>>>>    	  This option is selected by any driver which needs to access
>>>>    	  the host side of a virtio ring.
>>>> -menuconfig VHOST
>>>> -	tristate "Host kernel accelerator for virtio (VHOST)"
>>>> -	depends on EVENTFD
>>>> +config VHOST
>>>> +	tristate
>>>>    	select VHOST_IOTLB
>>>>    	help
>>>>    	  This option is selected by any driver which needs to access
>>>>    	  the core of vhost.
>>>> -if VHOST
>>>> +menuconfig VHOST_MENU
>>>> +	bool "VHOST drivers"
>>>> +	default y
>>>> +
>>>> +if VHOST_MENU
>>>>    config VHOST_NET
>>>>    	tristate "Host kernel accelerator for virtio net"
>>>>    	depends on NET && EVENTFD && (TUN || !TUN) && (TAP || !TAP)
>>>> +	select VHOST
>>>>    	---help---
>>>>    	  This kernel module can be loaded in host kernel to accelerate
>>>>    	  guest networking with virtio_net. Not to be confused with virtio_net
>>>> @@ -35,6 +39,7 @@ config VHOST_NET
>>>>    config VHOST_SCSI
>>>>    	tristate "VHOST_SCSI TCM fabric driver"
>>>>    	depends on TARGET_CORE && EVENTFD
>>>> +	select VHOST
>>>>    	default n
>>>>    	---help---
>>>>    	Say M here to enable the vhost_scsi TCM fabric module
>>>> @@ -43,6 +48,7 @@ config VHOST_SCSI
>>>>    config VHOST_VSOCK
>>>>    	tristate "vhost virtio-vsock driver"
>>>>    	depends on VSOCKETS && EVENTFD
>>>> +	select VHOST
>>>>    	select VIRTIO_VSOCKETS_COMMON
>>>>    	default n
>>>>    	---help---
>>>> @@ -56,6 +62,7 @@ config VHOST_VSOCK
>>>>    config VHOST_VDPA
>>>>    	tristate "Vhost driver for vDPA-based backend"
>>>>    	depends on EVENTFD
>>>> +	select VHOST
>>
>> This part is not squashed.
>>
>>
>>>>    	select VDPA
>>>>    	help
>>>>    	  This kernel module can be loaded in host kernel to accelerate
>>> OK so I squashed this into the original buggy patch.
>>> Could you please play with vhost branch of my tree on various
>>> arches? If it looks ok to you let me know I'll push
>>> this to next.
>>
>> With the above part squashed. I've tested all the archs whose defconfig have
>> VHOST_NET or VHOST_VSOCK enabled.
>>
>> All looks fine.
>>
>> Thanks
>
> I'm a bit confused. So is the next tag in my tree ok now?


Still need to select CONFIG_VHOST for  CONFIG_VHOST_VDPA. Others are ok.

Thanks


>


^ permalink raw reply	[flat|nested] 38+ messages in thread

* Re: [PATCH V9 1/9] vhost: refine vhost and vringh kconfig
  2020-04-02 14:23                 ` Jason Wang
@ 2020-04-02 14:38                   ` Michael S. Tsirkin
  2020-04-02 14:56                     ` Jason Wang
  0 siblings, 1 reply; 38+ messages in thread
From: Michael S. Tsirkin @ 2020-04-02 14:38 UTC (permalink / raw)
  To: Jason Wang
  Cc: linux-kernel, kvm, virtualization, netdev, jgg, maxime.coquelin,
	cunming.liang, zhihong.wang, rob.miller, xiao.w.wang,
	lingshan.zhu, eperezma, lulu, parav, kevin.tian, stefanha,
	rdunlap, hch, aadam, jiri, shahafs, hanand, mhabets, gdawar,
	saugatm, vmireyno, zhangweining

On Thu, Apr 02, 2020 at 10:23:59PM +0800, Jason Wang wrote:
> 
> On 2020/4/2 下午10:03, Michael S. Tsirkin wrote:
> > On Thu, Apr 02, 2020 at 11:22:57AM +0800, Jason Wang wrote:
> > > On 2020/4/2 上午12:08, Michael S. Tsirkin wrote:
> > > > On Wed, Apr 01, 2020 at 10:29:32PM +0800, Jason Wang wrote:
> > > > > >From 9b3a5d23b8bf6b0a11e65e688335d782f8e6aa5c Mon Sep 17 00:00:00 2001
> > > > > From: Jason Wang <jasowang@redhat.com>
> > > > > Date: Wed, 1 Apr 2020 22:17:27 +0800
> > > > > Subject: [PATCH] vhost: let CONFIG_VHOST to be selected by drivers
> > > > > 
> > > > > The defconfig on some archs enable vhost_net or vhost_vsock by
> > > > > default. So instead of adding CONFIG_VHOST=m to all of those files,
> > > > > simply letting CONFIG_VHOST to be selected by all of the vhost
> > > > > drivers. This fixes the build on the archs with CONFIG_VHOST_NET=m in
> > > > > their defconfig.
> > > > > 
> > > > > Signed-off-by: Jason Wang <jasowang@redhat.com>
> > > > > ---
> > > > >    drivers/vhost/Kconfig | 15 +++++++++++----
> > > > >    1 file changed, 11 insertions(+), 4 deletions(-)
> > > > > 
> > > > > diff --git a/drivers/vhost/Kconfig b/drivers/vhost/Kconfig
> > > > > index 2523a1d4290a..362b832f5338 100644
> > > > > --- a/drivers/vhost/Kconfig
> > > > > +++ b/drivers/vhost/Kconfig
> > > > > @@ -11,19 +11,23 @@ config VHOST_RING
> > > > >    	  This option is selected by any driver which needs to access
> > > > >    	  the host side of a virtio ring.
> > > > > -menuconfig VHOST
> > > > > -	tristate "Host kernel accelerator for virtio (VHOST)"
> > > > > -	depends on EVENTFD
> > > > > +config VHOST
> > > > > +	tristate
> > > > >    	select VHOST_IOTLB
> > > > >    	help
> > > > >    	  This option is selected by any driver which needs to access
> > > > >    	  the core of vhost.
> > > > > -if VHOST
> > > > > +menuconfig VHOST_MENU
> > > > > +	bool "VHOST drivers"
> > > > > +	default y
> > > > > +
> > > > > +if VHOST_MENU
> > > > >    config VHOST_NET
> > > > >    	tristate "Host kernel accelerator for virtio net"
> > > > >    	depends on NET && EVENTFD && (TUN || !TUN) && (TAP || !TAP)
> > > > > +	select VHOST
> > > > >    	---help---
> > > > >    	  This kernel module can be loaded in host kernel to accelerate
> > > > >    	  guest networking with virtio_net. Not to be confused with virtio_net
> > > > > @@ -35,6 +39,7 @@ config VHOST_NET
> > > > >    config VHOST_SCSI
> > > > >    	tristate "VHOST_SCSI TCM fabric driver"
> > > > >    	depends on TARGET_CORE && EVENTFD
> > > > > +	select VHOST
> > > > >    	default n
> > > > >    	---help---
> > > > >    	Say M here to enable the vhost_scsi TCM fabric module
> > > > > @@ -43,6 +48,7 @@ config VHOST_SCSI
> > > > >    config VHOST_VSOCK
> > > > >    	tristate "vhost virtio-vsock driver"
> > > > >    	depends on VSOCKETS && EVENTFD
> > > > > +	select VHOST
> > > > >    	select VIRTIO_VSOCKETS_COMMON
> > > > >    	default n
> > > > >    	---help---
> > > > > @@ -56,6 +62,7 @@ config VHOST_VSOCK
> > > > >    config VHOST_VDPA
> > > > >    	tristate "Vhost driver for vDPA-based backend"
> > > > >    	depends on EVENTFD
> > > > > +	select VHOST
> > > 
> > > This part is not squashed.
> > > 
> > > 
> > > > >    	select VDPA
> > > > >    	help
> > > > >    	  This kernel module can be loaded in host kernel to accelerate
> > > > OK so I squashed this into the original buggy patch.
> > > > Could you please play with vhost branch of my tree on various
> > > > arches? If it looks ok to you let me know I'll push
> > > > this to next.
> > > 
> > > With the above part squashed. I've tested all the archs whose defconfig have
> > > VHOST_NET or VHOST_VSOCK enabled.
> > > 
> > > All looks fine.
> > > 
> > > Thanks
> > 
> > I'm a bit confused. So is the next tag in my tree ok now?
> 
> 
> Still need to select CONFIG_VHOST for  CONFIG_VHOST_VDPA. Others are ok.
> 
> Thanks


Oh like this then?

diff --git a/drivers/vhost/Kconfig b/drivers/vhost/Kconfig
index bdd270fede26..cb6b17323eb2 100644
--- a/drivers/vhost/Kconfig
+++ b/drivers/vhost/Kconfig
@@ -61,6 +63,7 @@ config VHOST_VSOCK
 config VHOST_VDPA
 	tristate "Vhost driver for vDPA-based backend"
 	depends on EVENTFD
+	select VHOST
 	select VDPA
 	help
 	  This kernel module can be loaded in host kernel to accelerate


^ permalink raw reply	[flat|nested] 38+ messages in thread

* Re: [PATCH V9 1/9] vhost: refine vhost and vringh kconfig
  2020-04-02 14:38                   ` Michael S. Tsirkin
@ 2020-04-02 14:56                     ` Jason Wang
  0 siblings, 0 replies; 38+ messages in thread
From: Jason Wang @ 2020-04-02 14:56 UTC (permalink / raw)
  To: Michael S. Tsirkin
  Cc: linux-kernel, kvm, virtualization, netdev, jgg, maxime.coquelin,
	cunming.liang, zhihong.wang, rob.miller, xiao.w.wang,
	lingshan.zhu, eperezma, lulu, parav, kevin.tian, stefanha,
	rdunlap, hch, aadam, jiri, shahafs, hanand, mhabets, gdawar,
	saugatm, vmireyno, zhangweining


On 2020/4/2 下午10:38, Michael S. Tsirkin wrote:
> On Thu, Apr 02, 2020 at 10:23:59PM +0800, Jason Wang wrote:
>> On 2020/4/2 下午10:03, Michael S. Tsirkin wrote:
>>> On Thu, Apr 02, 2020 at 11:22:57AM +0800, Jason Wang wrote:
>>>> On 2020/4/2 上午12:08, Michael S. Tsirkin wrote:
>>>>> On Wed, Apr 01, 2020 at 10:29:32PM +0800, Jason Wang wrote:
>>>>>> >From 9b3a5d23b8bf6b0a11e65e688335d782f8e6aa5c Mon Sep 17 00:00:00 2001
>>>>>> From: Jason Wang <jasowang@redhat.com>
>>>>>> Date: Wed, 1 Apr 2020 22:17:27 +0800
>>>>>> Subject: [PATCH] vhost: let CONFIG_VHOST to be selected by drivers
>>>>>>
>>>>>> The defconfig on some archs enable vhost_net or vhost_vsock by
>>>>>> default. So instead of adding CONFIG_VHOST=m to all of those files,
>>>>>> simply letting CONFIG_VHOST to be selected by all of the vhost
>>>>>> drivers. This fixes the build on the archs with CONFIG_VHOST_NET=m in
>>>>>> their defconfig.
>>>>>>
>>>>>> Signed-off-by: Jason Wang <jasowang@redhat.com>
>>>>>> ---
>>>>>>     drivers/vhost/Kconfig | 15 +++++++++++----
>>>>>>     1 file changed, 11 insertions(+), 4 deletions(-)
>>>>>>
>>>>>> diff --git a/drivers/vhost/Kconfig b/drivers/vhost/Kconfig
>>>>>> index 2523a1d4290a..362b832f5338 100644
>>>>>> --- a/drivers/vhost/Kconfig
>>>>>> +++ b/drivers/vhost/Kconfig
>>>>>> @@ -11,19 +11,23 @@ config VHOST_RING
>>>>>>     	  This option is selected by any driver which needs to access
>>>>>>     	  the host side of a virtio ring.
>>>>>> -menuconfig VHOST
>>>>>> -	tristate "Host kernel accelerator for virtio (VHOST)"
>>>>>> -	depends on EVENTFD
>>>>>> +config VHOST
>>>>>> +	tristate
>>>>>>     	select VHOST_IOTLB
>>>>>>     	help
>>>>>>     	  This option is selected by any driver which needs to access
>>>>>>     	  the core of vhost.
>>>>>> -if VHOST
>>>>>> +menuconfig VHOST_MENU
>>>>>> +	bool "VHOST drivers"
>>>>>> +	default y
>>>>>> +
>>>>>> +if VHOST_MENU
>>>>>>     config VHOST_NET
>>>>>>     	tristate "Host kernel accelerator for virtio net"
>>>>>>     	depends on NET && EVENTFD && (TUN || !TUN) && (TAP || !TAP)
>>>>>> +	select VHOST
>>>>>>     	---help---
>>>>>>     	  This kernel module can be loaded in host kernel to accelerate
>>>>>>     	  guest networking with virtio_net. Not to be confused with virtio_net
>>>>>> @@ -35,6 +39,7 @@ config VHOST_NET
>>>>>>     config VHOST_SCSI
>>>>>>     	tristate "VHOST_SCSI TCM fabric driver"
>>>>>>     	depends on TARGET_CORE && EVENTFD
>>>>>> +	select VHOST
>>>>>>     	default n
>>>>>>     	---help---
>>>>>>     	Say M here to enable the vhost_scsi TCM fabric module
>>>>>> @@ -43,6 +48,7 @@ config VHOST_SCSI
>>>>>>     config VHOST_VSOCK
>>>>>>     	tristate "vhost virtio-vsock driver"
>>>>>>     	depends on VSOCKETS && EVENTFD
>>>>>> +	select VHOST
>>>>>>     	select VIRTIO_VSOCKETS_COMMON
>>>>>>     	default n
>>>>>>     	---help---
>>>>>> @@ -56,6 +62,7 @@ config VHOST_VSOCK
>>>>>>     config VHOST_VDPA
>>>>>>     	tristate "Vhost driver for vDPA-based backend"
>>>>>>     	depends on EVENTFD
>>>>>> +	select VHOST
>>>> This part is not squashed.
>>>>
>>>>
>>>>>>     	select VDPA
>>>>>>     	help
>>>>>>     	  This kernel module can be loaded in host kernel to accelerate
>>>>> OK so I squashed this into the original buggy patch.
>>>>> Could you please play with vhost branch of my tree on various
>>>>> arches? If it looks ok to you let me know I'll push
>>>>> this to next.
>>>> With the above part squashed. I've tested all the archs whose defconfig have
>>>> VHOST_NET or VHOST_VSOCK enabled.
>>>>
>>>> All looks fine.
>>>>
>>>> Thanks
>>> I'm a bit confused. So is the next tag in my tree ok now?
>>
>> Still need to select CONFIG_VHOST for  CONFIG_VHOST_VDPA. Others are ok.
>>
>> Thanks
>
> Oh like this then?
>
> diff --git a/drivers/vhost/Kconfig b/drivers/vhost/Kconfig
> index bdd270fede26..cb6b17323eb2 100644
> --- a/drivers/vhost/Kconfig
> +++ b/drivers/vhost/Kconfig
> @@ -61,6 +63,7 @@ config VHOST_VSOCK
>   config VHOST_VDPA
>   	tristate "Vhost driver for vDPA-based backend"
>   	depends on EVENTFD
> +	select VHOST
>   	select VDPA
>   	help
>   	  This kernel module can be loaded in host kernel to accelerate


Yes.

Thanks


>


^ permalink raw reply	[flat|nested] 38+ messages in thread

end of thread, back to index

Thread overview: 38+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-03-26 14:01 [PATCH V9 0/9] vDPA support Jason Wang
2020-03-26 14:01 ` [PATCH V9 1/9] vhost: refine vhost and vringh kconfig Jason Wang
2020-04-01 11:21   ` Christian Borntraeger
2020-04-01 12:50     ` Jason Wang
2020-04-01 12:56       ` Christian Borntraeger
2020-04-01 13:02         ` Christian Borntraeger
2020-04-01 14:01           ` Michael S. Tsirkin
2020-04-01 14:13           ` Jason Wang
2020-04-01 14:18             ` Michael S. Tsirkin
2020-04-01 14:36               ` Jason Wang
2020-04-01 14:27             ` Michael S. Tsirkin
2020-04-01 14:50               ` Jason Wang
2020-04-01 15:57                 ` Michael S. Tsirkin
2020-04-01 18:53                   ` Christian Borntraeger
2020-04-01 13:22   ` Michael S. Tsirkin
2020-04-01 14:08     ` Jason Wang
2020-04-01 14:13       ` Michael S. Tsirkin
2020-04-01 14:29         ` Jason Wang
2020-04-01 14:35           ` Michael S. Tsirkin
2020-04-01 14:39             ` Jason Wang
2020-04-01 14:39           ` Michael S. Tsirkin
2020-04-01 14:43             ` Jason Wang
2020-04-01 16:05           ` Michael S. Tsirkin
2020-04-01 16:08           ` Michael S. Tsirkin
2020-04-02  3:22             ` Jason Wang
2020-04-02 14:03               ` Michael S. Tsirkin
2020-04-02 14:23                 ` Jason Wang
2020-04-02 14:38                   ` Michael S. Tsirkin
2020-04-02 14:56                     ` Jason Wang
2020-03-26 14:01 ` [PATCH V9 2/9] vhost: allow per device message handler Jason Wang
2020-03-26 14:01 ` [PATCH V9 3/9] vhost: factor out IOTLB Jason Wang
2020-03-26 14:01 ` [PATCH V9 4/9] vringh: IOTLB support Jason Wang
2020-03-26 14:01 ` [PATCH V9 5/9] vDPA: introduce vDPA bus Jason Wang
2020-03-26 14:01 ` [PATCH V9 6/9] virtio: introduce a vDPA based transport Jason Wang
2020-03-26 14:01 ` [PATCH V9 7/9] vhost: introduce vDPA-based backend Jason Wang
2020-03-26 14:01 ` [PATCH V9 8/9] vdpasim: vDPA device simulator Jason Wang
2020-03-26 14:01 ` [PATCH V9 9/9] virtio: Intel IFC VF driver for VDPA Jason Wang
2020-03-29 11:07 ` [PATCH V9 0/9] vDPA support Michael S. Tsirkin

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