From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:35573) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1f97Vq-0003zy-GR for qemu-devel@nongnu.org; Thu, 19 Apr 2018 07:14:07 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1f97Vl-0002PO-H9 for qemu-devel@nongnu.org; Thu, 19 Apr 2018 07:14:02 -0400 Received: from mga12.intel.com ([192.55.52.136]:22907) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1f97Vl-0002OF-2w for qemu-devel@nongnu.org; Thu, 19 Apr 2018 07:13:57 -0400 Date: Thu, 19 Apr 2018 19:14:39 +0800 From: Tiwei Bie Message-ID: <20180419111439.i6gfhnept6wy7uzp@debian> References: <20180412151232.17506-1-tiwei.bie@intel.com> <20180412151232.17506-7-tiwei.bie@intel.com> <20180418192154-mutt-send-email-mst@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20180418192154-mutt-send-email-mst@kernel.org> Subject: Re: [Qemu-devel] [PATCH v3 6/6] vhost-user: support registering external host notifiers List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Michael S. Tsirkin" Cc: jasowang@redhat.com, alex.williamson@redhat.com, pbonzini@redhat.com, stefanha@redhat.com, qemu-devel@nongnu.org, virtio-dev@lists.oasis-open.org, cunming.liang@intel.com, dan.daly@intel.com, jianfeng.tan@intel.com, zhihong.wang@intel.com, xiao.w.wang@intel.com On Wed, Apr 18, 2018 at 07:34:06PM +0300, Michael S. Tsirkin wrote: > On Thu, Apr 12, 2018 at 11:12:32PM +0800, Tiwei Bie wrote: > > This patch introduces VHOST_USER_PROTOCOL_F_HOST_NOTIFIER. > > With this feature negotiated, vhost-user backend can register > > memory region based host notifiers. And it will allow the guest > > driver in the VM to notify the hardware accelerator at the > > vhost-user backend directly. > > > > Signed-off-by: Tiwei Bie > > Overall I think we can merge this approach, but I have two main concerns > about this: > > 1. Testing. Most people do not have the virtio hardware > so how to make sure this does not bit rot? > > I have an idea: add an option like this to libvhost-user. > Naturally libvhost-user can not get notified about a write > to an mmapped area, but it can write a special value there > (e.g. all-ones?) and then poll it to detect VQ # writes. > > Then include a vhost user bridge test with an option like this. > > I'd like to see a patch doing this. Sure, I'll do it. Thanks for the suggestion! > > 2. Memory barriers. Right now after updating the avail idx, > virtio does smp_wmb() and then the MMIO write. > Normal hardware drivers do wmb() which is an sfence. > Can a PCI device read bypass index write and see a stale > index value? It depends on arch's memory model. Cunming will provide more details about this later. > To make virtio pci do wmb() we would need a new feature bit. > Alternatively I guess we could maybe look at subsystem vendor/device id. > > I'd like to see a patch doing one of these things. We prefer to add a new feature bit as it's a more robust way to do this. I'll send out some patches soon. Thank you very much! :) Best regards, Tiwei Bie > > Thanks! > > > --- > > docs/interop/vhost-user.txt | 33 +++++++++++ > > hw/virtio/vhost-user.c | 123 +++++++++++++++++++++++++++++++++++++++++ > > include/hw/virtio/vhost-user.h | 8 +++ > > 3 files changed, 164 insertions(+) > > > > diff --git a/docs/interop/vhost-user.txt b/docs/interop/vhost-user.txt > > index 534caab18a..9e57b36b20 100644 > > --- a/docs/interop/vhost-user.txt > > +++ b/docs/interop/vhost-user.txt > > @@ -132,6 +132,16 @@ Depending on the request type, payload can be: > > Payload: Size bytes array holding the contents of the virtio > > device's configuration space > > > > + * Vring area description > > + ----------------------- > > + | u64 | size | offset | > > + ----------------------- > > + > > + u64: a 64-bit integer contains vring index and flags > > + Size: a 64-bit size of this area > > + Offset: a 64-bit offset of this area from the start of the > > + supplied file descriptor > > + > > In QEMU the vhost-user message is implemented with the following struct: > > > > typedef struct VhostUserMsg { > > @@ -146,6 +156,7 @@ typedef struct VhostUserMsg { > > VhostUserLog log; > > struct vhost_iotlb_msg iotlb; > > VhostUserConfig config; > > + VhostUserVringArea area; > > }; > > } QEMU_PACKED VhostUserMsg; > > > > @@ -380,6 +391,7 @@ Protocol features > > #define VHOST_USER_PROTOCOL_F_CRYPTO_SESSION 7 > > #define VHOST_USER_PROTOCOL_F_PAGEFAULT 8 > > #define VHOST_USER_PROTOCOL_F_CONFIG 9 > > +#define VHOST_USER_PROTOCOL_F_HOST_NOTIFIER 10 > > > > Master message types > > -------------------- > > @@ -777,6 +789,27 @@ Slave message types > > the VHOST_USER_NEED_REPLY flag, master must respond with zero when > > operation is successfully completed, or non-zero otherwise. > > > > + * VHOST_USER_SLAVE_VRING_HOST_NOTIFIER_MSG > > + > > + Id: 3 > > + Equivalent ioctl: N/A > > + Slave payload: vring area description > > + Master payload: N/A > > + > > + Sets host notifier for a specified queue. The queue index is contained > > + in the u64 field of the vring area description. The host notifier is > > + described by the file descriptor (typically it's a VFIO device fd) which > > + is passed as ancillary data and the size (which is mmap size and should > > + be the same as host page size) and offset (which is mmap offset) carried > > + in the vring area description. QEMU can mmap the file descriptor based > > + on the size and offset to get a memory range. Registering a host notifier > > + means mapping this memory range to the VM as the specified queue's notify > > + MMIO region. Slave sends this request to tell QEMU to de-register the > > + existing notifier if any and register the new notifier if the request is > > + sent with a file descriptor. > > + This request should be sent only when VHOST_USER_PROTOCOL_F_HOST_NOTIFIER > > + protocol feature has been successfully negotiated. > > + > > VHOST_USER_PROTOCOL_F_REPLY_ACK: > > ------------------------------- > > The original vhost-user specification only demands replies for certain > > diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c > > index 791e0a4763..1cd9c7276b 100644 > > --- a/hw/virtio/vhost-user.c > > +++ b/hw/virtio/vhost-user.c > > @@ -13,6 +13,7 @@ > > #include "hw/virtio/vhost.h" > > #include "hw/virtio/vhost-user.h" > > #include "hw/virtio/vhost-backend.h" > > +#include "hw/virtio/virtio.h" > > #include "hw/virtio/virtio-net.h" > > #include "chardev/char-fe.h" > > #include "sysemu/kvm.h" > > @@ -48,6 +49,7 @@ enum VhostUserProtocolFeature { > > VHOST_USER_PROTOCOL_F_CRYPTO_SESSION = 7, > > VHOST_USER_PROTOCOL_F_PAGEFAULT = 8, > > VHOST_USER_PROTOCOL_F_CONFIG = 9, > > + VHOST_USER_PROTOCOL_F_HOST_NOTIFIER = 10, > > VHOST_USER_PROTOCOL_F_MAX > > }; > > > > @@ -92,6 +94,7 @@ typedef enum VhostUserSlaveRequest { > > VHOST_USER_SLAVE_NONE = 0, > > VHOST_USER_SLAVE_IOTLB_MSG = 1, > > VHOST_USER_SLAVE_CONFIG_CHANGE_MSG = 2, > > + VHOST_USER_SLAVE_VRING_HOST_NOTIFIER_MSG = 3, > > VHOST_USER_SLAVE_MAX > > } VhostUserSlaveRequest; > > > > @@ -136,6 +139,12 @@ static VhostUserConfig c __attribute__ ((unused)); > > + sizeof(c.size) \ > > + sizeof(c.flags)) > > > > +typedef struct VhostUserVringArea { > > + uint64_t u64; > > + uint64_t size; > > + uint64_t offset; > > +} VhostUserVringArea; > > + > > typedef struct { > > VhostUserRequest request; > > > > @@ -157,6 +166,7 @@ typedef union { > > struct vhost_iotlb_msg iotlb; > > VhostUserConfig config; > > VhostUserCryptoSession session; > > + VhostUserVringArea area; > > } VhostUserPayload; > > > > typedef struct VhostUserMsg { > > @@ -638,9 +648,37 @@ static int vhost_user_set_vring_num(struct vhost_dev *dev, > > return vhost_set_vring(dev, VHOST_USER_SET_VRING_NUM, ring); > > } > > > > +static void vhost_user_host_notifier_restore(struct vhost_dev *dev, > > + int queue_idx) > > +{ > > + struct vhost_user *u = dev->opaque; > > + VhostUserHostNotifier *n = &u->user->notifier[queue_idx]; > > + VirtIODevice *vdev = dev->vdev; > > + > > + if (n->addr && !n->set) { > > + virtio_queue_set_host_notifier_mr(vdev, queue_idx, &n->mr, true); > > + n->set = true; > > + } > > +} > > + > > +static void vhost_user_host_notifier_remove(struct vhost_dev *dev, > > + int queue_idx) > > +{ > > + struct vhost_user *u = dev->opaque; > > + VhostUserHostNotifier *n = &u->user->notifier[queue_idx]; > > + VirtIODevice *vdev = dev->vdev; > > + > > + if (n->addr && n->set) { > > + virtio_queue_set_host_notifier_mr(vdev, queue_idx, &n->mr, false); > > + n->set = false; > > + } > > +} > > + > > static int vhost_user_set_vring_base(struct vhost_dev *dev, > > struct vhost_vring_state *ring) > > { > > + vhost_user_host_notifier_restore(dev, ring->index); > > + > > return vhost_set_vring(dev, VHOST_USER_SET_VRING_BASE, ring); > > } > > > > @@ -674,6 +712,8 @@ static int vhost_user_get_vring_base(struct vhost_dev *dev, > > .hdr.size = sizeof(msg.payload.state), > > }; > > > > + vhost_user_host_notifier_remove(dev, ring->index); > > + > > if (vhost_user_write(dev, &msg, NULL, 0) < 0) { > > return -1; > > } > > @@ -847,6 +887,76 @@ static int vhost_user_slave_handle_config_change(struct vhost_dev *dev) > > return ret; > > } > > > > +static int vhost_user_slave_handle_vring_host_notifier(struct vhost_dev *dev, > > + VhostUserVringArea *area, > > + int fd) > > +{ > > + int queue_idx = area->u64 & VHOST_USER_VRING_IDX_MASK; > > + size_t page_size = qemu_real_host_page_size; > > + struct vhost_user *u = dev->opaque; > > + VhostUserState *user = u->user; > > + VirtIODevice *vdev = dev->vdev; > > + VhostUserHostNotifier *n; > > + int ret = 0; > > + void *addr; > > + char *name; > > + > > + if (!virtio_has_feature(dev->protocol_features, > > + VHOST_USER_PROTOCOL_F_HOST_NOTIFIER) || > > + vdev == NULL || queue_idx >= virtio_get_num_queues(vdev)) { > > + ret = -1; > > + goto out; > > + } > > + > > + n = &user->notifier[queue_idx]; > > + > > + if (n->addr) { > > + virtio_queue_set_host_notifier_mr(vdev, queue_idx, &n->mr, false); > > + object_unparent(OBJECT(&n->mr)); > > + munmap(n->addr, page_size); > > + n->addr = NULL; > > + } > > + > > + if (area->u64 & VHOST_USER_VRING_NOFD_MASK) { > > + goto out; > > + } > > + > > + /* Sanity check. */ > > + if (area->size != page_size) { > > + ret = -1; > > + goto out; > > + } > > + > > + addr = mmap(NULL, page_size, PROT_READ | PROT_WRITE, MAP_SHARED, > > + fd, area->offset); > > + if (addr == MAP_FAILED) { > > + ret = -1; > > + goto out; > > + } > > + > > + name = g_strdup_printf("vhost-user/host-notifier@%p mmaps[%d]", > > + user, queue_idx); > > + memory_region_init_ram_device_ptr(&n->mr, OBJECT(vdev), name, > > + page_size, addr); > > + g_free(name); > > + > > + if (virtio_queue_set_host_notifier_mr(vdev, queue_idx, &n->mr, true)) { > > + munmap(addr, page_size); > > + ret = -1; > > + goto out; > > + } > > + > > + n->addr = addr; > > + n->set = true; > > + > > +out: > > + /* Always close the fd. */ > > + if (fd != -1) { > > + close(fd); > > + } > > + return ret; > > +} > > + > > static void slave_read(void *opaque) > > { > > struct vhost_dev *dev = opaque; > > @@ -913,6 +1023,10 @@ static void slave_read(void *opaque) > > case VHOST_USER_SLAVE_CONFIG_CHANGE_MSG : > > ret = vhost_user_slave_handle_config_change(dev); > > break; > > + case VHOST_USER_SLAVE_VRING_HOST_NOTIFIER_MSG: > > + ret = vhost_user_slave_handle_vring_host_notifier(dev, &payload.area, > > + fd); > > + break; > > default: > > error_report("Received unexpected msg type."); > > if (fd != -1) { > > @@ -1641,6 +1755,15 @@ VhostUserState *vhost_user_init(void) > > > > void vhost_user_cleanup(VhostUserState *user) > > { > > + int i; > > + > > + for (i = 0; i < VIRTIO_QUEUE_MAX; i++) { > > + if (user->notifier[i].addr) { > > + object_unparent(OBJECT(&user->notifier[i].mr)); > > + munmap(user->notifier[i].addr, qemu_real_host_page_size); > > + user->notifier[i].addr = NULL; > > + } > > + } > > } > > > > const VhostOps user_ops = { > > diff --git a/include/hw/virtio/vhost-user.h b/include/hw/virtio/vhost-user.h > > index eb8bc0d90d..fd660393a0 100644 > > --- a/include/hw/virtio/vhost-user.h > > +++ b/include/hw/virtio/vhost-user.h > > @@ -9,9 +9,17 @@ > > #define HW_VIRTIO_VHOST_USER_H > > > > #include "chardev/char-fe.h" > > +#include "hw/virtio/virtio.h" > > + > > +typedef struct VhostUserHostNotifier { > > + MemoryRegion mr; > > + void *addr; > > + bool set; > > +} VhostUserHostNotifier; > > > > typedef struct VhostUserState { > > CharBackend *chr; > > + VhostUserHostNotifier notifier[VIRTIO_QUEUE_MAX]; > > } VhostUserState; > > > > VhostUserState *vhost_user_init(void); > > -- > > 2.11.0 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: virtio-dev-return-3875-cohuck=redhat.com@lists.oasis-open.org Sender: List-Post: List-Help: List-Unsubscribe: List-Subscribe: Received: from lists.oasis-open.org (oasis-open.org [66.179.20.138]) by lists.oasis-open.org (Postfix) with ESMTP id 510875818097 for ; Thu, 19 Apr 2018 04:13:58 -0700 (PDT) Date: Thu, 19 Apr 2018 19:14:39 +0800 From: Tiwei Bie Message-ID: <20180419111439.i6gfhnept6wy7uzp@debian> References: <20180412151232.17506-1-tiwei.bie@intel.com> <20180412151232.17506-7-tiwei.bie@intel.com> <20180418192154-mutt-send-email-mst@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20180418192154-mutt-send-email-mst@kernel.org> Subject: [virtio-dev] Re: [PATCH v3 6/6] vhost-user: support registering external host notifiers To: "Michael S. Tsirkin" Cc: jasowang@redhat.com, alex.williamson@redhat.com, pbonzini@redhat.com, stefanha@redhat.com, qemu-devel@nongnu.org, virtio-dev@lists.oasis-open.org, cunming.liang@intel.com, dan.daly@intel.com, jianfeng.tan@intel.com, zhihong.wang@intel.com, xiao.w.wang@intel.com List-ID: On Wed, Apr 18, 2018 at 07:34:06PM +0300, Michael S. Tsirkin wrote: > On Thu, Apr 12, 2018 at 11:12:32PM +0800, Tiwei Bie wrote: > > This patch introduces VHOST_USER_PROTOCOL_F_HOST_NOTIFIER. > > With this feature negotiated, vhost-user backend can register > > memory region based host notifiers. And it will allow the guest > > driver in the VM to notify the hardware accelerator at the > > vhost-user backend directly. > > > > Signed-off-by: Tiwei Bie > > Overall I think we can merge this approach, but I have two main concerns > about this: > > 1. Testing. Most people do not have the virtio hardware > so how to make sure this does not bit rot? > > I have an idea: add an option like this to libvhost-user. > Naturally libvhost-user can not get notified about a write > to an mmapped area, but it can write a special value there > (e.g. all-ones?) and then poll it to detect VQ # writes. > > Then include a vhost user bridge test with an option like this. > > I'd like to see a patch doing this. Sure, I'll do it. Thanks for the suggestion! > > 2. Memory barriers. Right now after updating the avail idx, > virtio does smp_wmb() and then the MMIO write. > Normal hardware drivers do wmb() which is an sfence. > Can a PCI device read bypass index write and see a stale > index value? It depends on arch's memory model. Cunming will provide more details about this later. > To make virtio pci do wmb() we would need a new feature bit. > Alternatively I guess we could maybe look at subsystem vendor/device id. > > I'd like to see a patch doing one of these things. We prefer to add a new feature bit as it's a more robust way to do this. I'll send out some patches soon. Thank you very much! :) Best regards, Tiwei Bie > > Thanks! > > > --- > > docs/interop/vhost-user.txt | 33 +++++++++++ > > hw/virtio/vhost-user.c | 123 +++++++++++++++++++++++++++++++++++++++++ > > include/hw/virtio/vhost-user.h | 8 +++ > > 3 files changed, 164 insertions(+) > > > > diff --git a/docs/interop/vhost-user.txt b/docs/interop/vhost-user.txt > > index 534caab18a..9e57b36b20 100644 > > --- a/docs/interop/vhost-user.txt > > +++ b/docs/interop/vhost-user.txt > > @@ -132,6 +132,16 @@ Depending on the request type, payload can be: > > Payload: Size bytes array holding the contents of the virtio > > device's configuration space > > > > + * Vring area description > > + ----------------------- > > + | u64 | size | offset | > > + ----------------------- > > + > > + u64: a 64-bit integer contains vring index and flags > > + Size: a 64-bit size of this area > > + Offset: a 64-bit offset of this area from the start of the > > + supplied file descriptor > > + > > In QEMU the vhost-user message is implemented with the following struct: > > > > typedef struct VhostUserMsg { > > @@ -146,6 +156,7 @@ typedef struct VhostUserMsg { > > VhostUserLog log; > > struct vhost_iotlb_msg iotlb; > > VhostUserConfig config; > > + VhostUserVringArea area; > > }; > > } QEMU_PACKED VhostUserMsg; > > > > @@ -380,6 +391,7 @@ Protocol features > > #define VHOST_USER_PROTOCOL_F_CRYPTO_SESSION 7 > > #define VHOST_USER_PROTOCOL_F_PAGEFAULT 8 > > #define VHOST_USER_PROTOCOL_F_CONFIG 9 > > +#define VHOST_USER_PROTOCOL_F_HOST_NOTIFIER 10 > > > > Master message types > > -------------------- > > @@ -777,6 +789,27 @@ Slave message types > > the VHOST_USER_NEED_REPLY flag, master must respond with zero when > > operation is successfully completed, or non-zero otherwise. > > > > + * VHOST_USER_SLAVE_VRING_HOST_NOTIFIER_MSG > > + > > + Id: 3 > > + Equivalent ioctl: N/A > > + Slave payload: vring area description > > + Master payload: N/A > > + > > + Sets host notifier for a specified queue. The queue index is contained > > + in the u64 field of the vring area description. The host notifier is > > + described by the file descriptor (typically it's a VFIO device fd) which > > + is passed as ancillary data and the size (which is mmap size and should > > + be the same as host page size) and offset (which is mmap offset) carried > > + in the vring area description. QEMU can mmap the file descriptor based > > + on the size and offset to get a memory range. Registering a host notifier > > + means mapping this memory range to the VM as the specified queue's notify > > + MMIO region. Slave sends this request to tell QEMU to de-register the > > + existing notifier if any and register the new notifier if the request is > > + sent with a file descriptor. > > + This request should be sent only when VHOST_USER_PROTOCOL_F_HOST_NOTIFIER > > + protocol feature has been successfully negotiated. > > + > > VHOST_USER_PROTOCOL_F_REPLY_ACK: > > ------------------------------- > > The original vhost-user specification only demands replies for certain > > diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c > > index 791e0a4763..1cd9c7276b 100644 > > --- a/hw/virtio/vhost-user.c > > +++ b/hw/virtio/vhost-user.c > > @@ -13,6 +13,7 @@ > > #include "hw/virtio/vhost.h" > > #include "hw/virtio/vhost-user.h" > > #include "hw/virtio/vhost-backend.h" > > +#include "hw/virtio/virtio.h" > > #include "hw/virtio/virtio-net.h" > > #include "chardev/char-fe.h" > > #include "sysemu/kvm.h" > > @@ -48,6 +49,7 @@ enum VhostUserProtocolFeature { > > VHOST_USER_PROTOCOL_F_CRYPTO_SESSION = 7, > > VHOST_USER_PROTOCOL_F_PAGEFAULT = 8, > > VHOST_USER_PROTOCOL_F_CONFIG = 9, > > + VHOST_USER_PROTOCOL_F_HOST_NOTIFIER = 10, > > VHOST_USER_PROTOCOL_F_MAX > > }; > > > > @@ -92,6 +94,7 @@ typedef enum VhostUserSlaveRequest { > > VHOST_USER_SLAVE_NONE = 0, > > VHOST_USER_SLAVE_IOTLB_MSG = 1, > > VHOST_USER_SLAVE_CONFIG_CHANGE_MSG = 2, > > + VHOST_USER_SLAVE_VRING_HOST_NOTIFIER_MSG = 3, > > VHOST_USER_SLAVE_MAX > > } VhostUserSlaveRequest; > > > > @@ -136,6 +139,12 @@ static VhostUserConfig c __attribute__ ((unused)); > > + sizeof(c.size) \ > > + sizeof(c.flags)) > > > > +typedef struct VhostUserVringArea { > > + uint64_t u64; > > + uint64_t size; > > + uint64_t offset; > > +} VhostUserVringArea; > > + > > typedef struct { > > VhostUserRequest request; > > > > @@ -157,6 +166,7 @@ typedef union { > > struct vhost_iotlb_msg iotlb; > > VhostUserConfig config; > > VhostUserCryptoSession session; > > + VhostUserVringArea area; > > } VhostUserPayload; > > > > typedef struct VhostUserMsg { > > @@ -638,9 +648,37 @@ static int vhost_user_set_vring_num(struct vhost_dev *dev, > > return vhost_set_vring(dev, VHOST_USER_SET_VRING_NUM, ring); > > } > > > > +static void vhost_user_host_notifier_restore(struct vhost_dev *dev, > > + int queue_idx) > > +{ > > + struct vhost_user *u = dev->opaque; > > + VhostUserHostNotifier *n = &u->user->notifier[queue_idx]; > > + VirtIODevice *vdev = dev->vdev; > > + > > + if (n->addr && !n->set) { > > + virtio_queue_set_host_notifier_mr(vdev, queue_idx, &n->mr, true); > > + n->set = true; > > + } > > +} > > + > > +static void vhost_user_host_notifier_remove(struct vhost_dev *dev, > > + int queue_idx) > > +{ > > + struct vhost_user *u = dev->opaque; > > + VhostUserHostNotifier *n = &u->user->notifier[queue_idx]; > > + VirtIODevice *vdev = dev->vdev; > > + > > + if (n->addr && n->set) { > > + virtio_queue_set_host_notifier_mr(vdev, queue_idx, &n->mr, false); > > + n->set = false; > > + } > > +} > > + > > static int vhost_user_set_vring_base(struct vhost_dev *dev, > > struct vhost_vring_state *ring) > > { > > + vhost_user_host_notifier_restore(dev, ring->index); > > + > > return vhost_set_vring(dev, VHOST_USER_SET_VRING_BASE, ring); > > } > > > > @@ -674,6 +712,8 @@ static int vhost_user_get_vring_base(struct vhost_dev *dev, > > .hdr.size = sizeof(msg.payload.state), > > }; > > > > + vhost_user_host_notifier_remove(dev, ring->index); > > + > > if (vhost_user_write(dev, &msg, NULL, 0) < 0) { > > return -1; > > } > > @@ -847,6 +887,76 @@ static int vhost_user_slave_handle_config_change(struct vhost_dev *dev) > > return ret; > > } > > > > +static int vhost_user_slave_handle_vring_host_notifier(struct vhost_dev *dev, > > + VhostUserVringArea *area, > > + int fd) > > +{ > > + int queue_idx = area->u64 & VHOST_USER_VRING_IDX_MASK; > > + size_t page_size = qemu_real_host_page_size; > > + struct vhost_user *u = dev->opaque; > > + VhostUserState *user = u->user; > > + VirtIODevice *vdev = dev->vdev; > > + VhostUserHostNotifier *n; > > + int ret = 0; > > + void *addr; > > + char *name; > > + > > + if (!virtio_has_feature(dev->protocol_features, > > + VHOST_USER_PROTOCOL_F_HOST_NOTIFIER) || > > + vdev == NULL || queue_idx >= virtio_get_num_queues(vdev)) { > > + ret = -1; > > + goto out; > > + } > > + > > + n = &user->notifier[queue_idx]; > > + > > + if (n->addr) { > > + virtio_queue_set_host_notifier_mr(vdev, queue_idx, &n->mr, false); > > + object_unparent(OBJECT(&n->mr)); > > + munmap(n->addr, page_size); > > + n->addr = NULL; > > + } > > + > > + if (area->u64 & VHOST_USER_VRING_NOFD_MASK) { > > + goto out; > > + } > > + > > + /* Sanity check. */ > > + if (area->size != page_size) { > > + ret = -1; > > + goto out; > > + } > > + > > + addr = mmap(NULL, page_size, PROT_READ | PROT_WRITE, MAP_SHARED, > > + fd, area->offset); > > + if (addr == MAP_FAILED) { > > + ret = -1; > > + goto out; > > + } > > + > > + name = g_strdup_printf("vhost-user/host-notifier@%p mmaps[%d]", > > + user, queue_idx); > > + memory_region_init_ram_device_ptr(&n->mr, OBJECT(vdev), name, > > + page_size, addr); > > + g_free(name); > > + > > + if (virtio_queue_set_host_notifier_mr(vdev, queue_idx, &n->mr, true)) { > > + munmap(addr, page_size); > > + ret = -1; > > + goto out; > > + } > > + > > + n->addr = addr; > > + n->set = true; > > + > > +out: > > + /* Always close the fd. */ > > + if (fd != -1) { > > + close(fd); > > + } > > + return ret; > > +} > > + > > static void slave_read(void *opaque) > > { > > struct vhost_dev *dev = opaque; > > @@ -913,6 +1023,10 @@ static void slave_read(void *opaque) > > case VHOST_USER_SLAVE_CONFIG_CHANGE_MSG : > > ret = vhost_user_slave_handle_config_change(dev); > > break; > > + case VHOST_USER_SLAVE_VRING_HOST_NOTIFIER_MSG: > > + ret = vhost_user_slave_handle_vring_host_notifier(dev, &payload.area, > > + fd); > > + break; > > default: > > error_report("Received unexpected msg type."); > > if (fd != -1) { > > @@ -1641,6 +1755,15 @@ VhostUserState *vhost_user_init(void) > > > > void vhost_user_cleanup(VhostUserState *user) > > { > > + int i; > > + > > + for (i = 0; i < VIRTIO_QUEUE_MAX; i++) { > > + if (user->notifier[i].addr) { > > + object_unparent(OBJECT(&user->notifier[i].mr)); > > + munmap(user->notifier[i].addr, qemu_real_host_page_size); > > + user->notifier[i].addr = NULL; > > + } > > + } > > } > > > > const VhostOps user_ops = { > > diff --git a/include/hw/virtio/vhost-user.h b/include/hw/virtio/vhost-user.h > > index eb8bc0d90d..fd660393a0 100644 > > --- a/include/hw/virtio/vhost-user.h > > +++ b/include/hw/virtio/vhost-user.h > > @@ -9,9 +9,17 @@ > > #define HW_VIRTIO_VHOST_USER_H > > > > #include "chardev/char-fe.h" > > +#include "hw/virtio/virtio.h" > > + > > +typedef struct VhostUserHostNotifier { > > + MemoryRegion mr; > > + void *addr; > > + bool set; > > +} VhostUserHostNotifier; > > > > typedef struct VhostUserState { > > CharBackend *chr; > > + VhostUserHostNotifier notifier[VIRTIO_QUEUE_MAX]; > > } VhostUserState; > > > > VhostUserState *vhost_user_init(void); > > -- > > 2.11.0 --------------------------------------------------------------------- To unsubscribe, e-mail: virtio-dev-unsubscribe@lists.oasis-open.org For additional commands, e-mail: virtio-dev-help@lists.oasis-open.org