[PATCH 0/2] Intel IFC VF driver for VDPA

[PATCH 0/2] Intel IFC VF driver for VDPA

[Zhu Lingshan]

Hi all:
  This series intends to introduce Intel IFC VF NIC driver for Vhost
Data Plane Acceleration(VDPA).
  
Here comes two main parts, one is ifcvf_base layer, which handles
hardware operations. The other is ifcvf_main layer handles VF
initialization, configuration and removal, which depends on
and complys to:
virtio_mdev https://lkml.org/lkml/2019/10/30/62 
vhost_mdev https://lkml.org/lkml/2019/10/31/440

This patchset passed netperf tests.

This is RFC V2, plese help review.

Changes from V1:
using le32_to_cpu() to convert PCI capabilities.
some set /get  operations will sync with the hardware, eg get_status
and get_generation.
remove feature bit VHOST_F_LOG_ALL, add VIRTIO_F_ORDERED_PLATFORM
add get/set_config functions.
split mdev type group into mdev_type_group_virtio and mdev_type_group_vhost
add ifcvf_mdev_get_mdev_features()
coding stype changes.

Zhu Lingshan (2):
  IFC hardware operation layer
  IFC VDPA layer

 drivers/vhost/ifcvf/ifcvf_base.c | 344 ++++++++++++++++++++++
 drivers/vhost/ifcvf/ifcvf_base.h | 132 +++++++++
 drivers/vhost/ifcvf/ifcvf_main.c | 605 +++++++++++++++++++++++++++++++++++++++
 3 files changed, 1081 insertions(+)
 create mode 100644 drivers/vhost/ifcvf/ifcvf_base.c
 create mode 100644 drivers/vhost/ifcvf/ifcvf_base.h
 create mode 100644 drivers/vhost/ifcvf/ifcvf_main.c

-- 
1.8.3.1

[PATCH 1/2] IFC hardware operation layer

[Zhu Lingshan]

This commit introduced ifcvf_base layer, which handles hardware
operations and configurations.

Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
---
 drivers/vhost/ifcvf/ifcvf_base.c | 344 +++++++++++++++++++++++++++++++++++++++
 drivers/vhost/ifcvf/ifcvf_base.h | 132 +++++++++++++++
 2 files changed, 476 insertions(+)
 create mode 100644 drivers/vhost/ifcvf/ifcvf_base.c
 create mode 100644 drivers/vhost/ifcvf/ifcvf_base.h

diff --git a/drivers/vhost/ifcvf/ifcvf_base.c b/drivers/vhost/ifcvf/ifcvf_base.c
new file mode 100644
index 0000000..0659f41
--- /dev/null
+++ b/drivers/vhost/ifcvf/ifcvf_base.c
@@ -0,0 +1,344 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2019 Intel Corporation.
+ */
+
+#include "ifcvf_base.h"
+
+static void *get_cap_addr(struct ifcvf_hw *hw, struct virtio_pci_cap *cap)
+{
+	struct ifcvf_adapter *ifcvf;
+	u32 length, offset;
+	u8 bar;
+
+	length = le32_to_cpu(cap->length);
+	offset = le32_to_cpu(cap->offset);
+	bar = le32_to_cpu(cap->bar);
+
+	ifcvf = container_of(hw, struct ifcvf_adapter, vf);
+
+	if (bar >= IFCVF_PCI_MAX_RESOURCE) {
+		IFC_DBG(ifcvf->dev,
+			"Invalid bar number %u to get capabilities.\n", bar);
+		return NULL;
+	}
+
+	if (offset + length < offset) {
+		IFC_DBG(ifcvf->dev, "offset(%u) + length(%u) overflows\n",
+			offset, length);
+		return NULL;
+	}
+
+	if (offset + length > hw->mem_resource[cap->bar].len) {
+		IFC_DBG(ifcvf->dev,
+			"offset(%u) + len(%u) overflows bar%u to get capabilities.\n",
+			offset, length, bar);
+		return NULL;
+	}
+
+	return hw->mem_resource[bar].addr + offset;
+}
+
+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 *dev)
+{
+	struct virtio_pci_cap cap;
+	u16 notify_off;
+	int ret;
+	u8 pos;
+	u32 i;
+
+	ret = pci_read_config_byte(dev, PCI_CAPABILITY_LIST, &pos);
+
+	if (ret < 0) {
+		IFC_ERR(&dev->dev, "Failed to read PCI capability list.\n");
+		return -EIO;
+	}
+
+	while (pos) {
+		ret = ifcvf_read_config_range(dev, (u32 *)&cap,
+					      sizeof(cap), pos);
+
+		if (ret < 0) {
+			IFC_ERR(&dev->dev, "Failed to get PCI capability at %x",
+				pos);
+			break;
+		}
+
+		if (cap.cap_vndr != PCI_CAP_ID_VNDR)
+			goto next;
+
+		IFC_DBG(&dev->dev, "read PCI config: config type: %u, PCI bar: %u,\
+			 PCI bar offset: %u, PCI config len: %u.\n",
+			cap.cfg_type, cap.bar, cap.offset, cap.length);
+
+		switch (cap.cfg_type) {
+		case VIRTIO_PCI_CAP_COMMON_CFG:
+			hw->common_cfg = get_cap_addr(hw, &cap);
+			IFC_INFO(&dev->dev, "hw->common_cfg = %p.\n",
+				 hw->common_cfg);
+			break;
+		case VIRTIO_PCI_CAP_NOTIFY_CFG:
+			pci_read_config_dword(dev, pos + sizeof(cap),
+					      &hw->notify_off_multiplier);
+			hw->notify_bar = cap.bar;
+			hw->notify_base = get_cap_addr(hw, &cap);
+			IFC_INFO(&dev->dev, "hw->notify_base = %p.\n",
+				 hw->notify_base);
+			break;
+		case VIRTIO_PCI_CAP_ISR_CFG:
+			hw->isr = get_cap_addr(hw, &cap);
+			IFC_INFO(&dev->dev, "hw->isr = %p.\n", hw->isr);
+			break;
+		case VIRTIO_PCI_CAP_DEVICE_CFG:
+			hw->net_cfg = get_cap_addr(hw, &cap);
+			IFC_INFO(&dev->dev, "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) {
+		IFC_DBG(&dev->dev, "Incomplete PCI capabilities.\n");
+		return -1;
+	}
+
+	for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++) {
+		iowrite16(i, &hw->common_cfg->queue_select);
+		notify_off = ioread16(&hw->common_cfg->queue_notify_off);
+		hw->notify_addr[i] = (void *)((u8 *)hw->notify_base +
+				     notify_off * hw->notify_off_multiplier);
+	}
+
+	hw->lm_cfg = hw->mem_resource[IFCVF_LM_BAR].addr;
+
+	IFC_DBG(&dev->dev, "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)
+{
+	u8 old_gen, new_gen, status;
+
+	do {
+		old_gen = ioread8(&hw->common_cfg->config_generation);
+		status = ioread8(&hw->common_cfg->device_status);
+		new_gen = ioread8(&hw->common_cfg->config_generation);
+	} while (old_gen != new_gen);
+
+	return status;
+}
+
+void ifcvf_set_status(struct ifcvf_hw *hw, u8 status)
+{
+	iowrite8(status, &hw->common_cfg->device_status);
+}
+
+void ifcvf_reset(struct ifcvf_hw *hw)
+{
+	ifcvf_set_status(hw, 0);
+	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 *cfg = hw->common_cfg;
+	u32 features_lo, features_hi;
+
+	iowrite32(0, &cfg->device_feature_select);
+	features_lo = ioread32(&cfg->device_feature);
+
+	iowrite32(1, &cfg->device_feature_select);
+	features_hi = 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 ifcvf_net_config));
+
+	do {
+		old_gen = ioread8(&hw->common_cfg->config_generation);
+		p = dst;
+
+		for (i = 0; i < length; i++)
+			*p++ = ioread8((u8 *)hw->net_cfg + offset + i);
+
+		new_gen = 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 ifcvf_net_config));
+
+	for (i = 0; i < length; i++)
+		iowrite8(*p++, (u8 *)hw->net_cfg + offset + i);
+}
+
+static void ifcvf_set_features(struct ifcvf_hw *hw, u64 features)
+{
+	struct virtio_pci_common_cfg *cfg = hw->common_cfg;
+
+	iowrite32(0, &cfg->guest_feature_select);
+	iowrite32(features & ((1ULL << 32) - 1), &cfg->guest_feature);
+
+	iowrite32(1, &cfg->guest_feature_select);
+	iowrite32(features >> 32, &cfg->guest_feature);
+}
+
+static int ifcvf_config_features(struct ifcvf_hw *hw)
+{
+	struct ifcvf_adapter *ifcvf;
+
+	ifcvf =	container_of(hw, struct ifcvf_adapter, vf);
+	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)) {
+		IFC_ERR(ifcvf->dev, "Failed to set FEATURES_OK status\n");
+		return -EIO;
+	}
+
+	return 0;
+}
+
+void io_write64_twopart(u64 val, u32 *lo, u32 *hi)
+{
+	iowrite32(val & ((1ULL << 32) - 1), lo);
+	iowrite32(val >> 32, hi);
+}
+
+static int ifcvf_hw_enable(struct ifcvf_hw *hw)
+{
+	struct virtio_pci_common_cfg *cfg;
+	struct ifcvf_adapter *ifcvf;
+	u8 *lm_cfg;
+	u32 i;
+
+	ifcvf = container_of(hw, struct ifcvf_adapter, vf);
+	cfg = hw->common_cfg;
+	lm_cfg = hw->lm_cfg;
+	iowrite16(IFCVF_MSI_CONFIG_OFF, &cfg->msix_config);
+
+	if (ioread16(&cfg->msix_config) == VIRTIO_MSI_NO_VECTOR) {
+		IFC_ERR(ifcvf->dev, "No msix vector for device config.\n");
+		return -1;
+	}
+
+	for (i = 0; i < hw->nr_vring; i++) {
+		iowrite16(i, &cfg->queue_select);
+		io_write64_twopart(hw->vring[i].desc, &cfg->queue_desc_lo,
+				&cfg->queue_desc_hi);
+		io_write64_twopart(hw->vring[i].avail, &cfg->queue_avail_lo,
+				&cfg->queue_avail_hi);
+		io_write64_twopart(hw->vring[i].used, &cfg->queue_used_lo,
+				&cfg->queue_used_hi);
+		iowrite16(hw->vring[i].size, &cfg->queue_size);
+
+		*(u32 *)(lm_cfg + IFCVF_LM_RING_STATE_OFFSET +
+				(i / 2) * IFCVF_LM_CFG_SIZE + (i % 2) * 4) =
+			(u32)hw->vring[i].last_avail_idx |
+			((u32)hw->vring[i].last_used_idx << 16);
+
+		iowrite16(i + IFCVF_MSI_QUEUE_OFF, &cfg->queue_msix_vector);
+		if (ioread16(&cfg->queue_msix_vector) ==
+		    VIRTIO_MSI_NO_VECTOR) {
+			IFC_ERR(ifcvf->dev,
+				"No msix vector for queue %u.\n", i);
+			return -1;
+		}
+
+		iowrite16(1, &cfg->queue_enable);
+	}
+
+	return 0;
+}
+
+static void ifcvf_hw_disable(struct ifcvf_hw *hw)
+{
+	struct virtio_pci_common_cfg *cfg;
+	u32 i;
+
+	cfg = hw->common_cfg;
+	iowrite16(VIRTIO_MSI_NO_VECTOR, &cfg->msix_config);
+
+	for (i = 0; i < hw->nr_vring; i++) {
+		iowrite16(i, &cfg->queue_select);
+		iowrite16(0, &cfg->queue_enable);
+		iowrite16(VIRTIO_MSI_NO_VECTOR, &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 -1;
+
+	if (ifcvf_hw_enable(hw) < 0)
+		return -1;
+
+	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)
+{
+	iowrite16(qid, hw->notify_addr[qid]);
+}
+
+u64 ifcvf_get_queue_notify_off(struct ifcvf_hw *hw, int qid)
+{
+	return (u8 *)hw->notify_addr[qid] -
+		(u8 *)hw->mem_resource[hw->notify_bar].addr;
+}
diff --git a/drivers/vhost/ifcvf/ifcvf_base.h b/drivers/vhost/ifcvf/ifcvf_base.h
new file mode 100644
index 0000000..c97f0eb
--- /dev/null
+++ b/drivers/vhost/ifcvf/ifcvf_base.h
@@ -0,0 +1,132 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+/*
+ * Copyright (C) 2019 Intel Corporation.
+ */
+
+#ifndef _IFCVF_H_
+#define _IFCVF_H_
+
+#include <linux/virtio_mdev_ops.h>
+#include <linux/mdev.h>
+#include <linux/pci.h>
+#include <linux/pci_regs.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_MDEV_LIMIT	1
+
+/*
+ * Some ifcvf feature bits (currently bits 28 through 31) are
+ * reserved for the transport being used (eg. ifcvf_ring), the
+ * rest are per-device feature bits.
+ */
+#define IFCVF_TRANSPORT_F_START 28
+#define IFCVF_TRANSPORT_F_END   34
+
+#define IFC_SUPPORTED_FEATURES \
+		((1ULL << VIRTIO_NET_F_MAC)			| \
+		 (1ULL << VIRTIO_F_ANY_LAYOUT)			| \
+		 (1ULL << VIRTIO_F_VERSION_1)			| \
+		 (1ULL << VIRTIO_F_ORDER_PLATFORM)			| \
+		 (1ULL << VIRTIO_NET_F_GUEST_ANNOUNCE)		| \
+		 (1ULL << VIRTIO_NET_F_CTRL_VQ)			| \
+		 (1ULL << VIRTIO_NET_F_STATUS)			| \
+		 (1ULL << VIRTIO_NET_F_MRG_RXBUF)) /* not fully supported */
+
+//Not support MQ, only one queue pair for now.
+#define IFCVF_MAX_QUEUE_PAIRS		1
+#define IFCVF_MAX_QUEUES		2
+
+#define IFCVF_QUEUE_ALIGNMENT		PAGE_SIZE
+
+#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_32_BIT_MASK		0xffffffff
+
+#define IFC_ERR(dev, fmt, ...)	dev_err(dev, fmt, ##__VA_ARGS__)
+#define IFC_DBG(dev, fmt, ...)	dev_dbg(dev, fmt, ##__VA_ARGS__)
+#define IFC_INFO(dev, fmt, ...)	dev_info(dev, fmt, ##__VA_ARGS__)
+
+#define IFC_PRIVATE_TO_VF(adapter) \
+	(&((struct ifcvf_adapter *)adapter)->vf)
+
+#define IFCVF_MAX_INTR (IFCVF_MAX_QUEUE_PAIRS * 2 + 1)
+
+struct ifcvf_net_config {
+	u8    mac[6];
+	u16   status;
+	u16   max_virtqueue_pairs;
+} __packed;
+
+struct ifcvf_pci_mem_resource {
+	/* Physical address, 0 if not resource. */
+	u64      phys_addr;
+	/* Length of the resource. */
+	u64      len;
+	/* Virtual address, NULL when not mapped. */
+	u8       *addr;
+};
+
+struct vring_info {
+	u64 desc;
+	u64 avail;
+	u64 used;
+	u16 size;
+	u16 last_avail_idx;
+	u16 last_used_idx;
+	bool ready;
+	char msix_name[256];
+	struct virtio_mdev_callback cb;
+};
+
+struct ifcvf_hw {
+	u8	*isr;
+	u8	notify_bar;
+	u8	*lm_cfg;
+	u8	nr_vring;
+	u16	*notify_base;
+	u16	*notify_addr[IFCVF_MAX_QUEUE_PAIRS * 2];
+	u32	notify_off_multiplier;
+	u64	req_features;
+	struct	virtio_pci_common_cfg *common_cfg;
+	struct	ifcvf_net_config *net_cfg;
+	struct	vring_info vring[IFCVF_MAX_QUEUE_PAIRS * 2];
+	struct	ifcvf_pci_mem_resource mem_resource[IFCVF_PCI_MAX_RESOURCE];
+};
+
+struct ifcvf_adapter {
+	struct	device *dev;
+	struct	mutex mdev_lock;
+	int	mdev_count;
+	int	vectors;
+	struct	ifcvf_hw vf;
+};
+
+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);
+u8 ifcvf_get_linkstatus(struct ifcvf_hw *hw);
+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);
+
+#endif /* _IFCVF_H_ */
-- 
1.8.3.1

[PATCH 2/2] IFC VDPA layer

[Zhu Lingshan]

This commit introduced IFC operations for vdpa, which complys to
virtio_mdev and vhost_mdev interfaces, handles IFC VF
initialization, configuration and removal.

Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
---
 drivers/vhost/ifcvf/ifcvf_main.c | 605 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 605 insertions(+)
 create mode 100644 drivers/vhost/ifcvf/ifcvf_main.c

diff --git a/drivers/vhost/ifcvf/ifcvf_main.c b/drivers/vhost/ifcvf/ifcvf_main.c
new file mode 100644
index 0000000..7165457
--- /dev/null
+++ b/drivers/vhost/ifcvf/ifcvf_main.c
@@ -0,0 +1,605 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2019 Intel Corporation.
+ */
+
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/mdev.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 struct ifcvf_hw *mdev_to_vf(struct mdev_device *mdev)
+{
+	struct ifcvf_asapter *adapter = mdev_get_drvdata(mdev);
+	struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(adapter);
+
+	return vf;
+}
+
+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 u64 ifcvf_mdev_get_features(struct mdev_device *mdev)
+{
+	struct ifcvf_hw *vf = mdev_to_vf(mdev);
+
+	return ifcvf_get_features(vf);
+}
+
+static int ifcvf_mdev_set_features(struct mdev_device *mdev, u64 features)
+{
+	struct ifcvf_hw *vf = mdev_to_vf(mdev);
+
+	vf->req_features = features;
+
+	return 0;
+}
+
+static u64 ifcvf_mdev_get_vq_state(struct mdev_device *mdev, u16 qid)
+{
+	struct ifcvf_hw *vf = mdev_to_vf(mdev);
+	u16 last_avail_idx;
+
+	last_avail_idx = *(u16 *)(vf->lm_cfg + IFCVF_LM_RING_STATE_OFFSET +
+			 (qid / 2) * IFCVF_LM_CFG_SIZE + (qid % 2) * 4);
+
+	return last_avail_idx;
+}
+
+static int ifcvf_mdev_set_vq_state(struct mdev_device *mdev, u16 qid, u64 num)
+{
+	struct ifcvf_hw *vf = mdev_to_vf(mdev);
+
+	vf->vring[qid].last_avail_idx = num;
+
+	return 0;
+}
+
+static int ifcvf_mdev_set_vq_address(struct mdev_device *mdev, u16 idx,
+				     u64 desc_area, u64 driver_area,
+				     u64 device_area)
+{
+	struct ifcvf_hw *vf = mdev_to_vf(mdev);
+
+	vf->vring[idx].desc = desc_area;
+	vf->vring[idx].avail = driver_area;
+	vf->vring[idx].used = device_area;
+
+	return 0;
+}
+
+static void ifcvf_mdev_set_vq_num(struct mdev_device *mdev, u16 qid, u32 num)
+{
+	struct ifcvf_hw *vf = mdev_to_vf(mdev);
+
+	vf->vring[qid].size = num;
+}
+
+static void ifcvf_mdev_set_vq_ready(struct mdev_device *mdev,
+				    u16 qid, bool ready)
+{
+	struct ifcvf_hw *vf = mdev_to_vf(mdev);
+
+	vf->vring[qid].ready = ready;
+}
+
+static bool ifcvf_mdev_get_vq_ready(struct mdev_device *mdev, u16 qid)
+{
+	struct ifcvf_hw *vf = mdev_to_vf(mdev);
+
+	return vf->vring[qid].ready;
+}
+
+static void ifcvf_mdev_set_vq_cb(struct mdev_device *mdev, u16 idx,
+				 struct virtio_mdev_callback *cb)
+{
+	struct ifcvf_hw *vf = mdev_to_vf(mdev);
+
+	vf->vring[idx].cb = *cb;
+}
+
+static void ifcvf_mdev_kick_vq(struct mdev_device *mdev, u16 idx)
+{
+	struct ifcvf_hw *vf = mdev_to_vf(mdev);
+
+	ifcvf_notify_queue(vf, idx);
+}
+
+static u8 ifcvf_mdev_get_status(struct mdev_device *mdev)
+{
+	struct ifcvf_hw *vf = mdev_to_vf(mdev);
+
+	return ifcvf_get_status(vf);
+}
+
+static u32 ifcvf_mdev_get_generation(struct mdev_device *mdev)
+{
+	struct ifcvf_hw *vf = mdev_to_vf(mdev);
+
+	return ioread8(&vf->common_cfg->config_generation);
+}
+
+static u32 ifcvf_mdev_get_device_id(struct mdev_device *mdev)
+{
+	return VIRTIO_ID_NET;
+}
+
+static u32 ifcvf_mdev_get_vendor_id(struct mdev_device *mdev)
+{
+	return IFCVF_VENDOR_ID;
+}
+
+static u16 ifcvf_mdev_get_vq_align(struct mdev_device *mdev)
+{
+	return IFCVF_QUEUE_ALIGNMENT;
+}
+
+static u64 ifcvf_mdev_get_mdev_features(struct mdev_device *mdev)
+{
+	return VIRTIO_MDEV_F_VERSION_1;
+}
+
+static int ifcvf_start_datapath(void *private)
+{
+	struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(private);
+	struct ifcvf_adapter *ifcvf;
+	int i, ret = 0;
+
+	ifcvf = container_of(vf, struct ifcvf_adapter, vf);
+
+	for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++) {
+		if (!vf->vring[i].ready) {
+			IFC_ERR(ifcvf->dev,
+				"Failed to start datapath, vring %d not ready.\n", i);
+			return -EINVAL;
+		}
+
+		if (!vf->vring[i].size) {
+			IFC_ERR(ifcvf->dev,
+				"Failed to start datapath, vring %d size is zero.\n", i);
+			return -EINVAL;
+		}
+
+		if (!vf->vring[i].desc || !vf->vring[i].avail ||
+			!vf->vring[i].used) {
+			IFC_ERR(ifcvf->dev,
+				"Failed to start datapath, "
+				"invaild value for vring %d desc,"
+				"avail_idx or usex_idx.\n", i);
+			return -EINVAL;
+		}
+	}
+
+	vf->nr_vring = i;
+	ret = ifcvf_start_hw(vf);
+
+	return ret;
+}
+
+static int ifcvf_stop_datapath(void *private)
+{
+	struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(private);
+	int i;
+
+	for (i = 0; i < IFCVF_MAX_QUEUES; 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 = IFC_PRIVATE_TO_VF(adapter);
+	struct virtio_pci_common_cfg *cfg;
+	u8 *lm_cfg;
+	int i;
+
+	cfg = vf->common_cfg;
+	lm_cfg = vf->lm_cfg;
+
+	for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++) {
+		vf->vring[i].last_used_idx = 0;
+		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->cb.callback = NULL;
+		vf->vring->cb.private = NULL;
+
+	}
+
+	ifcvf_reset(vf);
+}
+
+static void ifcvf_mdev_set_status(struct mdev_device *mdev, u8 status)
+{
+	struct ifcvf_adapter *adapter = mdev_get_drvdata(mdev);
+	struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(adapter);
+	int ret = 0;
+
+	if (status == 0) {
+		ifcvf_stop_datapath(adapter);
+		ifcvf_reset_vring(adapter);
+		return;
+	}
+
+	if (status & VIRTIO_CONFIG_S_DRIVER_OK) {
+		ret = ifcvf_start_datapath(adapter);
+
+		if (ret)
+			IFC_ERR(adapter->dev, "Failed to set mdev status %u.\n",
+				status);
+	}
+
+	ifcvf_set_status(vf, status);
+}
+
+static u16 ifcvf_mdev_get_vq_num_max(struct mdev_device *mdev)
+{
+	struct ifcvf_hw *vf = mdev_to_vf(mdev);
+
+	return vf->vring[0].size;
+}
+static void ifcvf_mdev_get_config(struct mdev_device *mdev, unsigned int offset,
+			     void *buf, unsigned int len)
+{
+	struct ifcvf_hw *vf = mdev_to_vf(mdev);
+
+	WARN_ON(offset + len > sizeof(struct ifcvf_net_config));
+	ifcvf_read_net_config(vf, offset, buf, len);
+}
+
+static void ifcvf_mdev_set_config(struct mdev_device *mdev, unsigned int offset,
+			     const void *buf, unsigned int len)
+{
+	struct ifcvf_hw *vf = mdev_to_vf(mdev);
+
+	WARN_ON(offset + len > sizeof(struct ifcvf_net_config));
+	ifcvf_write_net_config(vf, offset, buf, len);
+}
+
+static struct virtio_mdev_device_ops ifc_mdev_ops = {
+	.get_features  = ifcvf_mdev_get_features,
+	.set_features  = ifcvf_mdev_set_features,
+	.get_status    = ifcvf_mdev_get_status,
+	.set_status    = ifcvf_mdev_set_status,
+	.get_vq_num_max = ifcvf_mdev_get_vq_num_max,
+	.get_vq_state   = ifcvf_mdev_get_vq_state,
+	.set_vq_state   = ifcvf_mdev_set_vq_state,
+	.set_vq_cb      = ifcvf_mdev_set_vq_cb,
+	.set_vq_ready   = ifcvf_mdev_set_vq_ready,
+	.get_vq_ready	= ifcvf_mdev_get_vq_ready,
+	.set_vq_num     = ifcvf_mdev_set_vq_num,
+	.set_vq_address = ifcvf_mdev_set_vq_address,
+	.kick_vq        = ifcvf_mdev_kick_vq,
+	.get_generation	= ifcvf_mdev_get_generation,
+	.get_device_id	= ifcvf_mdev_get_device_id,
+	.get_vendor_id	= ifcvf_mdev_get_vendor_id,
+	.get_vq_align	= ifcvf_mdev_get_vq_align,
+	.get_config	= ifcvf_mdev_get_config,
+	.set_config	= ifcvf_mdev_set_config,
+	.get_mdev_features = ifcvf_mdev_get_mdev_features,
+};
+
+static int ifcvf_init_msix(struct ifcvf_adapter *adapter)
+{
+	struct pci_dev *pdev = to_pci_dev(adapter->dev);
+	struct ifcvf_hw *vf = &adapter->vf;
+	int vector, i, ret, irq;
+
+	ret = pci_alloc_irq_vectors(pdev, IFCVF_MAX_INTR,
+				    IFCVF_MAX_INTR, PCI_IRQ_MSIX);
+	if (ret < 0) {
+		IFC_ERR(adapter->dev, "Failed to alloc irq vectors.\n");
+		return ret;
+	}
+
+	for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++) {
+		vector = i + IFCVF_MSI_QUEUE_OFF;
+		irq = pci_irq_vector(pdev, vector);
+		ret = request_irq(irq, ifcvf_intr_handler, 0,
+				pci_name(pdev), &vf->vring[i]);
+		if (ret) {
+			IFC_ERR(adapter->dev,
+				"Failed to request irq for vq %d.\n", i);
+			return ret;
+		}
+	}
+
+	return 0;
+}
+
+static void ifcvf_destroy_adapter(struct ifcvf_adapter *adapter)
+{
+	struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(adapter);
+	struct pci_dev *pdev = to_pci_dev(adapter->dev);
+	int i, vector, irq;
+
+	for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++) {
+		vector = i + IFCVF_MSI_QUEUE_OFF;
+		irq = pci_irq_vector(pdev, vector);
+		free_irq(irq, &vf->vring[i]);
+	}
+}
+
+static ssize_t name_show(struct kobject *kobj, struct device *dev, char *buf)
+{
+	const char *name = "vhost accelerator (virtio ring compatible)";
+
+	return sprintf(buf, "%s\n", name);
+}
+MDEV_TYPE_ATTR_RO(name);
+
+static ssize_t device_api_show(struct kobject *kobj, struct device *dev,
+			       char *buf)
+{
+	return sprintf(buf, "%s\n", VIRTIO_MDEV_DEVICE_API_STRING);
+}
+MDEV_TYPE_ATTR_RO(device_api);
+
+static ssize_t available_instances_show(struct kobject *kobj,
+					struct device *dev, char *buf)
+{
+	struct pci_dev *pdev;
+	struct ifcvf_adapter *adapter;
+
+	pdev = to_pci_dev(dev);
+	adapter = pci_get_drvdata(pdev);
+
+	return sprintf(buf, "%d\n", adapter->mdev_count);
+}
+
+MDEV_TYPE_ATTR_RO(available_instances);
+
+static ssize_t type_show(struct kobject *kobj,
+			struct device *dev, char *buf)
+{
+	return sprintf(buf, "%s\n", "net");
+}
+
+MDEV_TYPE_ATTR_RO(type);
+
+
+static struct attribute *mdev_types_attrs[] = {
+	&mdev_type_attr_name.attr,
+	&mdev_type_attr_device_api.attr,
+	&mdev_type_attr_available_instances.attr,
+	&mdev_type_attr_type.attr,
+	NULL,
+};
+
+static struct attribute_group mdev_type_group_virtio = {
+	.name  = "virtio_mdev",
+	.attrs = mdev_types_attrs,
+};
+
+static struct attribute_group mdev_type_group_vhost = {
+	.name  = "vhost_mdev",
+	.attrs = mdev_types_attrs,
+};
+
+static struct attribute_group *mdev_type_groups[] = {
+	&mdev_type_group_virtio,
+	&mdev_type_group_vhost,
+	NULL,
+};
+
+const struct attribute_group *mdev_dev_groups[] = {
+	NULL,
+};
+
+static int ifcvf_mdev_create(struct kobject *kobj, struct mdev_device *mdev)
+{
+	struct device *dev = mdev_parent_dev(mdev);
+	struct pci_dev *pdev = to_pci_dev(dev);
+	struct ifcvf_adapter *adapter = pci_get_drvdata(pdev);
+	int ret = 0;
+
+	mutex_lock(&adapter->mdev_lock);
+
+	if (adapter->mdev_count < IFCVF_MDEV_LIMIT) {
+		IFC_ERR(&pdev->dev,
+			"Can not create mdev, reached limitation %d.\n",
+			IFCVF_MDEV_LIMIT);
+		ret = -EINVAL;
+		goto out;
+	}
+
+	if (!strcmp(kobj->name, "ifcvf-virtio_mdev"))
+		mdev_set_virtio_ops(mdev, &ifc_mdev_ops);
+
+	if (!strcmp(kobj->name, "ifcvf-vhost_mdev"))
+		mdev_set_vhost_ops(mdev, &ifc_mdev_ops);
+
+	mdev_set_drvdata(mdev, adapter);
+	mdev_set_iommu_device(mdev_dev(mdev), dev);
+	adapter->mdev_count--;
+
+out:
+	mutex_unlock(&adapter->mdev_lock);
+	return ret;
+}
+
+static int ifcvf_mdev_remove(struct mdev_device *mdev)
+{
+	struct device *dev = mdev_parent_dev(mdev);
+	struct pci_dev *pdev = to_pci_dev(dev);
+	struct ifcvf_adapter *adapter = pci_get_drvdata(pdev);
+
+	mutex_lock(&adapter->mdev_lock);
+	adapter->mdev_count++;
+	mutex_unlock(&adapter->mdev_lock);
+
+	return 0;
+}
+
+static struct mdev_parent_ops ifcvf_mdev_fops = {
+	.owner			= THIS_MODULE,
+	.supported_type_groups	= mdev_type_groups,
+	.mdev_attr_groups	= mdev_dev_groups,
+	.create			= ifcvf_mdev_create,
+	.remove			= ifcvf_mdev_remove,
+};
+
+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, i;
+
+	adapter = kzalloc(sizeof(struct ifcvf_adapter), GFP_KERNEL);
+
+	if (adapter == NULL) {
+		ret = -ENOMEM;
+		goto fail;
+	}
+
+	mutex_init(&adapter->mdev_lock);
+	adapter->mdev_count = IFCVF_MDEV_LIMIT;
+	adapter->dev = dev;
+	pci_set_drvdata(pdev, adapter);
+	ret = pci_enable_device(pdev);
+
+	if (ret) {
+		IFC_ERR(adapter->dev, "Failed to enable device.\n");
+		goto free_adapter;
+	}
+
+	ret = pci_request_regions(pdev, IFCVF_DRIVER_NAME);
+
+	if (ret) {
+		IFC_ERR(adapter->dev, "Failed to request MMIO region.\n");
+		goto disable_device;
+	}
+
+	pci_set_master(pdev);
+	ret = ifcvf_init_msix(adapter);
+
+	if (ret) {
+		IFC_ERR(adapter->dev, "Failed to initialize MSIX.\n");
+		goto free_msix;
+	}
+
+	vf = &adapter->vf;
+	
+	for (i = 0; i < IFCVF_PCI_MAX_RESOURCE; i++) {
+		vf->mem_resource[i].phys_addr = pci_resource_start(pdev, i);
+		vf->mem_resource[i].len = pci_resource_len(pdev, i);
+		if (!vf->mem_resource[i].len) {
+			vf->mem_resource[i].addr = NULL;
+			continue;
+		}
+
+		vf->mem_resource[i].addr = pci_iomap_range(pdev, i, 0,
+				vf->mem_resource[i].len);
+		if (!vf->mem_resource[i].addr) {
+			IFC_ERR(adapter->dev, "Failed to map IO resource %d\n",
+				i);
+			ret = -1;
+			goto free_msix;
+		}
+	}
+
+	if (ifcvf_init_hw(vf, pdev) < 0) {
+		ret = -1;
+		goto destroy_adapter;
+	}
+
+	ret = mdev_register_device(dev, &ifcvf_mdev_fops);
+
+	if (ret) {
+		IFC_ERR(adapter->dev,  "Failed to register mdev device\n");
+		goto destroy_adapter;
+	}
+
+	return 0;
+
+destroy_adapter:
+	ifcvf_destroy_adapter(adapter);
+free_msix:
+	pci_free_irq_vectors(pdev);
+	pci_release_regions(pdev);
+disable_device:
+	pci_disable_device(pdev);
+free_adapter:
+	kfree(adapter);
+fail:
+	return ret;
+}
+
+static void ifcvf_remove(struct pci_dev *pdev)
+{
+	struct ifcvf_adapter *adapter = pci_get_drvdata(pdev);
+	struct device *dev = &pdev->dev;
+	struct ifcvf_hw *vf;
+	int i;
+
+	mdev_unregister_device(dev);
+
+	vf = &adapter->vf;
+	for (i = 0; i < IFCVF_PCI_MAX_RESOURCE; i++) {
+		if (vf->mem_resource[i].addr) {
+			pci_iounmap(pdev, vf->mem_resource[i].addr);
+			vf->mem_resource[i].addr = NULL;
+		}
+	}
+
+	ifcvf_destroy_adapter(adapter);
+	pci_free_irq_vectors(pdev);
+	pci_release_regions(pdev);
+	pci_disable_device(pdev);
+	kfree(adapter);
+}
+
+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,
+};
+
+static int __init ifcvf_init_module(void)
+{
+	int ret;
+
+	ret = pci_register_driver(&ifcvf_driver);
+	return ret;
+}
+
+static void __exit ifcvf_exit_module(void)
+{
+	pci_unregister_driver(&ifcvf_driver);
+}
+
+module_init(ifcvf_init_module);
+module_exit(ifcvf_exit_module);
+
+MODULE_LICENSE("GPL v2");
+MODULE_VERSION(VERSION_STRING);
+MODULE_AUTHOR(DRIVER_AUTHOR);
-- 
1.8.3.1

Re: [PATCH 1/2] IFC hardware operation layer

[Michael S. Tsirkin]

On Tue, Nov 05, 2019 at 05:37:39PM +0800, Zhu Lingshan wrote:
> This commit introduced ifcvf_base layer, which handles hardware
> operations and configurations.
> 
> Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
> ---
>  drivers/vhost/ifcvf/ifcvf_base.c | 344 +++++++++++++++++++++++++++++++++++++++
>  drivers/vhost/ifcvf/ifcvf_base.h | 132 +++++++++++++++
>  2 files changed, 476 insertions(+)
>  create mode 100644 drivers/vhost/ifcvf/ifcvf_base.c
>  create mode 100644 drivers/vhost/ifcvf/ifcvf_base.h
> 
> diff --git a/drivers/vhost/ifcvf/ifcvf_base.c b/drivers/vhost/ifcvf/ifcvf_base.c
> new file mode 100644
> index 0000000..0659f41
> --- /dev/null
> +++ b/drivers/vhost/ifcvf/ifcvf_base.c
> @@ -0,0 +1,344 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Copyright (C) 2019 Intel Corporation.
> + */
> +
> +#include "ifcvf_base.h"
> +
> +static void *get_cap_addr(struct ifcvf_hw *hw, struct virtio_pci_cap *cap)
> +{
> +	struct ifcvf_adapter *ifcvf;
> +	u32 length, offset;
> +	u8 bar;
> +
> +	length = le32_to_cpu(cap->length);
> +	offset = le32_to_cpu(cap->offset);
> +	bar = le32_to_cpu(cap->bar);
> +
> +	ifcvf = container_of(hw, struct ifcvf_adapter, vf);
> +
> +	if (bar >= IFCVF_PCI_MAX_RESOURCE) {
> +		IFC_DBG(ifcvf->dev,
> +			"Invalid bar number %u to get capabilities.\n", bar);
> +		return NULL;
> +	}
> +
> +	if (offset + length < offset) {
> +		IFC_DBG(ifcvf->dev, "offset(%u) + length(%u) overflows\n",
> +			offset, length);
> +		return NULL;
> +	}
> +
> +	if (offset + length > hw->mem_resource[cap->bar].len) {
> +		IFC_DBG(ifcvf->dev,
> +			"offset(%u) + len(%u) overflows bar%u to get capabilities.\n",
> +			offset, length, bar);
> +		return NULL;
> +	}
> +
> +	return hw->mem_resource[bar].addr + offset;
> +}
> +
> +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 *dev)
> +{
> +	struct virtio_pci_cap cap;
> +	u16 notify_off;
> +	int ret;
> +	u8 pos;
> +	u32 i;
> +
> +	ret = pci_read_config_byte(dev, PCI_CAPABILITY_LIST, &pos);
> +
> +	if (ret < 0) {
> +		IFC_ERR(&dev->dev, "Failed to read PCI capability list.\n");
> +		return -EIO;
> +	}
> +
> +	while (pos) {
> +		ret = ifcvf_read_config_range(dev, (u32 *)&cap,
> +					      sizeof(cap), pos);
> +
> +		if (ret < 0) {
> +			IFC_ERR(&dev->dev, "Failed to get PCI capability at %x",
> +				pos);
> +			break;
> +		}
> +
> +		if (cap.cap_vndr != PCI_CAP_ID_VNDR)
> +			goto next;
> +
> +		IFC_DBG(&dev->dev, "read PCI config: config type: %u, PCI bar: %u,\
> +			 PCI bar offset: %u, PCI config len: %u.\n",
> +			cap.cfg_type, cap.bar, cap.offset, cap.length);
> +
> +		switch (cap.cfg_type) {
> +		case VIRTIO_PCI_CAP_COMMON_CFG:
> +			hw->common_cfg = get_cap_addr(hw, &cap);
> +			IFC_INFO(&dev->dev, "hw->common_cfg = %p.\n",
> +				 hw->common_cfg);
> +			break;
> +		case VIRTIO_PCI_CAP_NOTIFY_CFG:
> +			pci_read_config_dword(dev, pos + sizeof(cap),
> +					      &hw->notify_off_multiplier);
> +			hw->notify_bar = cap.bar;
> +			hw->notify_base = get_cap_addr(hw, &cap);
> +			IFC_INFO(&dev->dev, "hw->notify_base = %p.\n",
> +				 hw->notify_base);
> +			break;
> +		case VIRTIO_PCI_CAP_ISR_CFG:
> +			hw->isr = get_cap_addr(hw, &cap);
> +			IFC_INFO(&dev->dev, "hw->isr = %p.\n", hw->isr);
> +			break;
> +		case VIRTIO_PCI_CAP_DEVICE_CFG:
> +			hw->net_cfg = get_cap_addr(hw, &cap);
> +			IFC_INFO(&dev->dev, "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) {
> +		IFC_DBG(&dev->dev, "Incomplete PCI capabilities.\n");
> +		return -1;
> +	}
> +
> +	for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++) {
> +		iowrite16(i, &hw->common_cfg->queue_select);
> +		notify_off = ioread16(&hw->common_cfg->queue_notify_off);
> +		hw->notify_addr[i] = (void *)((u8 *)hw->notify_base +
> +				     notify_off * hw->notify_off_multiplier);
> +	}
> +
> +	hw->lm_cfg = hw->mem_resource[IFCVF_LM_BAR].addr;
> +
> +	IFC_DBG(&dev->dev, "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)
> +{
> +	u8 old_gen, new_gen, status;
> +
> +	do {
> +		old_gen = ioread8(&hw->common_cfg->config_generation);
> +		status = ioread8(&hw->common_cfg->device_status);
> +		new_gen = ioread8(&hw->common_cfg->config_generation);
> +	} while (old_gen != new_gen);
> +
> +	return status;
> +}
> +
> +void ifcvf_set_status(struct ifcvf_hw *hw, u8 status)
> +{
> +	iowrite8(status, &hw->common_cfg->device_status);
> +}
> +
> +void ifcvf_reset(struct ifcvf_hw *hw)
> +{
> +	ifcvf_set_status(hw, 0);
> +	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 *cfg = hw->common_cfg;
> +	u32 features_lo, features_hi;
> +
> +	iowrite32(0, &cfg->device_feature_select);
> +	features_lo = ioread32(&cfg->device_feature);
> +
> +	iowrite32(1, &cfg->device_feature_select);
> +	features_hi = 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 ifcvf_net_config));
> +
> +	do {
> +		old_gen = ioread8(&hw->common_cfg->config_generation);
> +		p = dst;
> +
> +		for (i = 0; i < length; i++)
> +			*p++ = ioread8((u8 *)hw->net_cfg + offset + i);
> +
> +		new_gen = 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 ifcvf_net_config));
> +
> +	for (i = 0; i < length; i++)
> +		iowrite8(*p++, (u8 *)hw->net_cfg + offset + i);
> +}
> +
> +static void ifcvf_set_features(struct ifcvf_hw *hw, u64 features)
> +{
> +	struct virtio_pci_common_cfg *cfg = hw->common_cfg;
> +
> +	iowrite32(0, &cfg->guest_feature_select);
> +	iowrite32(features & ((1ULL << 32) - 1), &cfg->guest_feature);
> +
> +	iowrite32(1, &cfg->guest_feature_select);
> +	iowrite32(features >> 32, &cfg->guest_feature);
> +}
> +
> +static int ifcvf_config_features(struct ifcvf_hw *hw)
> +{
> +	struct ifcvf_adapter *ifcvf;
> +
> +	ifcvf =	container_of(hw, struct ifcvf_adapter, vf);
> +	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)) {
> +		IFC_ERR(ifcvf->dev, "Failed to set FEATURES_OK status\n");
> +		return -EIO;
> +	}
> +
> +	return 0;
> +}
> +
> +void io_write64_twopart(u64 val, u32 *lo, u32 *hi)
> +{
> +	iowrite32(val & ((1ULL << 32) - 1), lo);
> +	iowrite32(val >> 32, hi);
> +}
> +
> +static int ifcvf_hw_enable(struct ifcvf_hw *hw)
> +{
> +	struct virtio_pci_common_cfg *cfg;
> +	struct ifcvf_adapter *ifcvf;
> +	u8 *lm_cfg;
> +	u32 i;
> +
> +	ifcvf = container_of(hw, struct ifcvf_adapter, vf);
> +	cfg = hw->common_cfg;
> +	lm_cfg = hw->lm_cfg;
> +	iowrite16(IFCVF_MSI_CONFIG_OFF, &cfg->msix_config);
> +
> +	if (ioread16(&cfg->msix_config) == VIRTIO_MSI_NO_VECTOR) {
> +		IFC_ERR(ifcvf->dev, "No msix vector for device config.\n");
> +		return -1;
> +	}
> +
> +	for (i = 0; i < hw->nr_vring; i++) {
> +		iowrite16(i, &cfg->queue_select);
> +		io_write64_twopart(hw->vring[i].desc, &cfg->queue_desc_lo,
> +				&cfg->queue_desc_hi);
> +		io_write64_twopart(hw->vring[i].avail, &cfg->queue_avail_lo,
> +				&cfg->queue_avail_hi);
> +		io_write64_twopart(hw->vring[i].used, &cfg->queue_used_lo,
> +				&cfg->queue_used_hi);
> +		iowrite16(hw->vring[i].size, &cfg->queue_size);
> +
> +		*(u32 *)(lm_cfg + IFCVF_LM_RING_STATE_OFFSET +
> +				(i / 2) * IFCVF_LM_CFG_SIZE + (i % 2) * 4) =
> +			(u32)hw->vring[i].last_avail_idx |
> +			((u32)hw->vring[i].last_used_idx << 16);

Is this trying to store data into part of device memory BAR?
If yes doing it like this isn't portable I think.


> +
> +		iowrite16(i + IFCVF_MSI_QUEUE_OFF, &cfg->queue_msix_vector);
> +		if (ioread16(&cfg->queue_msix_vector) ==
> +		    VIRTIO_MSI_NO_VECTOR) {
> +			IFC_ERR(ifcvf->dev,
> +				"No msix vector for queue %u.\n", i);
> +			return -1;
> +		}
> +
> +		iowrite16(1, &cfg->queue_enable);
> +	}
> +
> +	return 0;
> +}
> +
> +static void ifcvf_hw_disable(struct ifcvf_hw *hw)
> +{
> +	struct virtio_pci_common_cfg *cfg;
> +	u32 i;
> +
> +	cfg = hw->common_cfg;
> +	iowrite16(VIRTIO_MSI_NO_VECTOR, &cfg->msix_config);
> +
> +	for (i = 0; i < hw->nr_vring; i++) {
> +		iowrite16(i, &cfg->queue_select);
> +		iowrite16(0, &cfg->queue_enable);
> +		iowrite16(VIRTIO_MSI_NO_VECTOR, &cfg->queue_msix_vector);
> +	}

Is it enough to write like this? don't you need to read
in order to flush outstanding MSI?


> +}
> +
> +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 -1;
> +
> +	if (ifcvf_hw_enable(hw) < 0)
> +		return -1;
> +
> +	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)
> +{
> +	iowrite16(qid, hw->notify_addr[qid]);

I suspect you didn't validate this driver with sparse, did you?
Otherwise I think you would have noticed some warnings
as e.g. iowrite16 requires a __iomem address.


> +}
> +
> +u64 ifcvf_get_queue_notify_off(struct ifcvf_hw *hw, int qid)
> +{
> +	return (u8 *)hw->notify_addr[qid] -
> +		(u8 *)hw->mem_resource[hw->notify_bar].addr;

why is the cast of addr need?

> +}
> diff --git a/drivers/vhost/ifcvf/ifcvf_base.h b/drivers/vhost/ifcvf/ifcvf_base.h
> new file mode 100644
> index 0000000..c97f0eb
> --- /dev/null
> +++ b/drivers/vhost/ifcvf/ifcvf_base.h
> @@ -0,0 +1,132 @@
> +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
> +/*
> + * Copyright (C) 2019 Intel Corporation.
> + */
> +
> +#ifndef _IFCVF_H_
> +#define _IFCVF_H_
> +
> +#include <linux/virtio_mdev_ops.h>
> +#include <linux/mdev.h>
> +#include <linux/pci.h>
> +#include <linux/pci_regs.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


I am confused by the above.

They are used by the virtio layer right?

So why isn't the id VIRTIO_ID_NET then?

> +#define IFCVF_SUBSYS_VENDOR_ID  0x8086
> +#define IFCVF_SUBSYS_DEVICE_ID  0x001A
> +
> +#define IFCVF_MDEV_LIMIT	1
> +
> +/*
> + * Some ifcvf feature bits (currently bits 28 through 31) are
> + * reserved for the transport being used (eg. ifcvf_ring), the
> + * rest are per-device feature bits.
> + */
> +#define IFCVF_TRANSPORT_F_START 28
> +#define IFCVF_TRANSPORT_F_END   34
> +
> +#define IFC_SUPPORTED_FEATURES \
> +		((1ULL << VIRTIO_NET_F_MAC)			| \
> +		 (1ULL << VIRTIO_F_ANY_LAYOUT)			| \
> +		 (1ULL << VIRTIO_F_VERSION_1)			| \
> +		 (1ULL << VIRTIO_F_ORDER_PLATFORM)			| \
> +		 (1ULL << VIRTIO_NET_F_GUEST_ANNOUNCE)		| \
> +		 (1ULL << VIRTIO_NET_F_CTRL_VQ)			| \
> +		 (1ULL << VIRTIO_NET_F_STATUS)			| \
> +		 (1ULL << VIRTIO_NET_F_MRG_RXBUF)) /* not fully supported */

what does this last one mean?
shouldn't we clear the bit if it's incomplete?

> +
> +//Not support MQ, only one queue pair for now.

/* comments like this pls */

> +#define IFCVF_MAX_QUEUE_PAIRS		1
> +#define IFCVF_MAX_QUEUES		2
> +
> +#define IFCVF_QUEUE_ALIGNMENT		PAGE_SIZE
> +
> +#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_32_BIT_MASK		0xffffffff
> +
> +#define IFC_ERR(dev, fmt, ...)	dev_err(dev, fmt, ##__VA_ARGS__)
> +#define IFC_DBG(dev, fmt, ...)	dev_dbg(dev, fmt, ##__VA_ARGS__)
> +#define IFC_INFO(dev, fmt, ...)	dev_info(dev, fmt, ##__VA_ARGS__)
> +
> +#define IFC_PRIVATE_TO_VF(adapter) \
> +	(&((struct ifcvf_adapter *)adapter)->vf)
> +
> +#define IFCVF_MAX_INTR (IFCVF_MAX_QUEUE_PAIRS * 2 + 1)
> +
> +struct ifcvf_net_config {
> +	u8    mac[6];
> +	u16   status;
> +	u16   max_virtqueue_pairs;
> +} __packed;

Looks like a partial copy of virtio_net_config - reuse that one instead?


> +
> +struct ifcvf_pci_mem_resource {
> +	/* Physical address, 0 if not resource. */
> +	u64      phys_addr;
> +	/* Length of the resource. */
> +	u64      len;
> +	/* Virtual address, NULL when not mapped. */
> +	u8       *addr;
> +};
> +
> +struct vring_info {
> +	u64 desc;
> +	u64 avail;
> +	u64 used;
> +	u16 size;
> +	u16 last_avail_idx;
> +	u16 last_used_idx;
> +	bool ready;
> +	char msix_name[256];
> +	struct virtio_mdev_callback cb;
> +};
> +
> +struct ifcvf_hw {
> +	u8	*isr;
> +	u8	notify_bar;
> +	u8	*lm_cfg;
> +	u8	nr_vring;
> +	u16	*notify_base;
> +	u16	*notify_addr[IFCVF_MAX_QUEUE_PAIRS * 2];
> +	u32	notify_off_multiplier;
> +	u64	req_features;
> +	struct	virtio_pci_common_cfg *common_cfg;
> +	struct	ifcvf_net_config *net_cfg;
> +	struct	vring_info vring[IFCVF_MAX_QUEUE_PAIRS * 2];
> +	struct	ifcvf_pci_mem_resource mem_resource[IFCVF_PCI_MAX_RESOURCE];
> +};
> +
> +struct ifcvf_adapter {
> +	struct	device *dev;
> +	struct	mutex mdev_lock;
> +	int	mdev_count;
> +	int	vectors;
> +	struct	ifcvf_hw vf;
> +};
> +
> +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);
> +u8 ifcvf_get_linkstatus(struct ifcvf_hw *hw);
> +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);
> +
> +#endif /* _IFCVF_H_ */
> -- 
> 1.8.3.1

Re: [PATCH 1/2] IFC hardware operation layer

[Michael S. Tsirkin]

On Tue, Nov 05, 2019 at 05:37:39PM +0800, Zhu Lingshan wrote:
> This commit introduced ifcvf_base layer, which handles hardware
> operations and configurations.
> 
> Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
> ---
>  drivers/vhost/ifcvf/ifcvf_base.c | 344 +++++++++++++++++++++++++++++++++++++++
>  drivers/vhost/ifcvf/ifcvf_base.h | 132 +++++++++++++++
>  2 files changed, 476 insertions(+)
>  create mode 100644 drivers/vhost/ifcvf/ifcvf_base.c
>  create mode 100644 drivers/vhost/ifcvf/ifcvf_base.h
> 
> diff --git a/drivers/vhost/ifcvf/ifcvf_base.c b/drivers/vhost/ifcvf/ifcvf_base.c
> new file mode 100644
> index 0000000..0659f41
> --- /dev/null
> +++ b/drivers/vhost/ifcvf/ifcvf_base.c
> @@ -0,0 +1,344 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Copyright (C) 2019 Intel Corporation.
> + */
> +
> +#include "ifcvf_base.h"
> +
> +static void *get_cap_addr(struct ifcvf_hw *hw, struct virtio_pci_cap *cap)
> +{
> +	struct ifcvf_adapter *ifcvf;
> +	u32 length, offset;
> +	u8 bar;
> +
> +	length = le32_to_cpu(cap->length);
> +	offset = le32_to_cpu(cap->offset);
> +	bar = le32_to_cpu(cap->bar);
> +
> +	ifcvf = container_of(hw, struct ifcvf_adapter, vf);
> +
> +	if (bar >= IFCVF_PCI_MAX_RESOURCE) {
> +		IFC_DBG(ifcvf->dev,
> +			"Invalid bar number %u to get capabilities.\n", bar);
> +		return NULL;
> +	}
> +
> +	if (offset + length < offset) {
> +		IFC_DBG(ifcvf->dev, "offset(%u) + length(%u) overflows\n",
> +			offset, length);
> +		return NULL;
> +	}
> +
> +	if (offset + length > hw->mem_resource[cap->bar].len) {
> +		IFC_DBG(ifcvf->dev,
> +			"offset(%u) + len(%u) overflows bar%u to get capabilities.\n",
> +			offset, length, bar);
> +		return NULL;
> +	}
> +
> +	return hw->mem_resource[bar].addr + offset;
> +}
> +
> +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 *dev)
> +{
> +	struct virtio_pci_cap cap;
> +	u16 notify_off;
> +	int ret;
> +	u8 pos;
> +	u32 i;
> +
> +	ret = pci_read_config_byte(dev, PCI_CAPABILITY_LIST, &pos);
> +
> +	if (ret < 0) {
> +		IFC_ERR(&dev->dev, "Failed to read PCI capability list.\n");
> +		return -EIO;
> +	}
> +
> +	while (pos) {
> +		ret = ifcvf_read_config_range(dev, (u32 *)&cap,
> +					      sizeof(cap), pos);
> +
> +		if (ret < 0) {
> +			IFC_ERR(&dev->dev, "Failed to get PCI capability at %x",
> +				pos);
> +			break;
> +		}
> +
> +		if (cap.cap_vndr != PCI_CAP_ID_VNDR)
> +			goto next;
> +
> +		IFC_DBG(&dev->dev, "read PCI config: config type: %u, PCI bar: %u,\
> +			 PCI bar offset: %u, PCI config len: %u.\n",
> +			cap.cfg_type, cap.bar, cap.offset, cap.length);
> +
> +		switch (cap.cfg_type) {
> +		case VIRTIO_PCI_CAP_COMMON_CFG:
> +			hw->common_cfg = get_cap_addr(hw, &cap);
> +			IFC_INFO(&dev->dev, "hw->common_cfg = %p.\n",
> +				 hw->common_cfg);
> +			break;
> +		case VIRTIO_PCI_CAP_NOTIFY_CFG:
> +			pci_read_config_dword(dev, pos + sizeof(cap),
> +					      &hw->notify_off_multiplier);
> +			hw->notify_bar = cap.bar;
> +			hw->notify_base = get_cap_addr(hw, &cap);
> +			IFC_INFO(&dev->dev, "hw->notify_base = %p.\n",
> +				 hw->notify_base);
> +			break;
> +		case VIRTIO_PCI_CAP_ISR_CFG:
> +			hw->isr = get_cap_addr(hw, &cap);
> +			IFC_INFO(&dev->dev, "hw->isr = %p.\n", hw->isr);
> +			break;
> +		case VIRTIO_PCI_CAP_DEVICE_CFG:
> +			hw->net_cfg = get_cap_addr(hw, &cap);
> +			IFC_INFO(&dev->dev, "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) {
> +		IFC_DBG(&dev->dev, "Incomplete PCI capabilities.\n");
> +		return -1;
> +	}
> +
> +	for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++) {
> +		iowrite16(i, &hw->common_cfg->queue_select);
> +		notify_off = ioread16(&hw->common_cfg->queue_notify_off);
> +		hw->notify_addr[i] = (void *)((u8 *)hw->notify_base +
> +				     notify_off * hw->notify_off_multiplier);
> +	}
> +
> +	hw->lm_cfg = hw->mem_resource[IFCVF_LM_BAR].addr;
> +
> +	IFC_DBG(&dev->dev, "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)
> +{
> +	u8 old_gen, new_gen, status;
> +
> +	do {
> +		old_gen = ioread8(&hw->common_cfg->config_generation);
> +		status = ioread8(&hw->common_cfg->device_status);
> +		new_gen = ioread8(&hw->common_cfg->config_generation);
> +	} while (old_gen != new_gen);
> +
> +	return status;
> +}
> +
> +void ifcvf_set_status(struct ifcvf_hw *hw, u8 status)
> +{
> +	iowrite8(status, &hw->common_cfg->device_status);
> +}
> +
> +void ifcvf_reset(struct ifcvf_hw *hw)
> +{
> +	ifcvf_set_status(hw, 0);
> +	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 *cfg = hw->common_cfg;
> +	u32 features_lo, features_hi;
> +
> +	iowrite32(0, &cfg->device_feature_select);
> +	features_lo = ioread32(&cfg->device_feature);
> +
> +	iowrite32(1, &cfg->device_feature_select);
> +	features_hi = 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 ifcvf_net_config));
> +
> +	do {
> +		old_gen = ioread8(&hw->common_cfg->config_generation);
> +		p = dst;
> +
> +		for (i = 0; i < length; i++)
> +			*p++ = ioread8((u8 *)hw->net_cfg + offset + i);
> +
> +		new_gen = 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 ifcvf_net_config));
> +
> +	for (i = 0; i < length; i++)
> +		iowrite8(*p++, (u8 *)hw->net_cfg + offset + i);
> +}
> +
> +static void ifcvf_set_features(struct ifcvf_hw *hw, u64 features)
> +{
> +	struct virtio_pci_common_cfg *cfg = hw->common_cfg;
> +
> +	iowrite32(0, &cfg->guest_feature_select);
> +	iowrite32(features & ((1ULL << 32) - 1), &cfg->guest_feature);
> +
> +	iowrite32(1, &cfg->guest_feature_select);
> +	iowrite32(features >> 32, &cfg->guest_feature);
> +}
> +
> +static int ifcvf_config_features(struct ifcvf_hw *hw)
> +{
> +	struct ifcvf_adapter *ifcvf;
> +
> +	ifcvf =	container_of(hw, struct ifcvf_adapter, vf);
> +	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)) {
> +		IFC_ERR(ifcvf->dev, "Failed to set FEATURES_OK status\n");
> +		return -EIO;
> +	}
> +
> +	return 0;
> +}
> +
> +void io_write64_twopart(u64 val, u32 *lo, u32 *hi)
> +{
> +	iowrite32(val & ((1ULL << 32) - 1), lo);
> +	iowrite32(val >> 32, hi);
> +}
> +
> +static int ifcvf_hw_enable(struct ifcvf_hw *hw)
> +{
> +	struct virtio_pci_common_cfg *cfg;
> +	struct ifcvf_adapter *ifcvf;
> +	u8 *lm_cfg;
> +	u32 i;
> +
> +	ifcvf = container_of(hw, struct ifcvf_adapter, vf);
> +	cfg = hw->common_cfg;
> +	lm_cfg = hw->lm_cfg;
> +	iowrite16(IFCVF_MSI_CONFIG_OFF, &cfg->msix_config);
> +
> +	if (ioread16(&cfg->msix_config) == VIRTIO_MSI_NO_VECTOR) {
> +		IFC_ERR(ifcvf->dev, "No msix vector for device config.\n");
> +		return -1;
> +	}
> +
> +	for (i = 0; i < hw->nr_vring; i++) {
> +		iowrite16(i, &cfg->queue_select);
> +		io_write64_twopart(hw->vring[i].desc, &cfg->queue_desc_lo,
> +				&cfg->queue_desc_hi);
> +		io_write64_twopart(hw->vring[i].avail, &cfg->queue_avail_lo,
> +				&cfg->queue_avail_hi);
> +		io_write64_twopart(hw->vring[i].used, &cfg->queue_used_lo,
> +				&cfg->queue_used_hi);
> +		iowrite16(hw->vring[i].size, &cfg->queue_size);
> +
> +		*(u32 *)(lm_cfg + IFCVF_LM_RING_STATE_OFFSET +
> +				(i / 2) * IFCVF_LM_CFG_SIZE + (i % 2) * 4) =
> +			(u32)hw->vring[i].last_avail_idx |
> +			((u32)hw->vring[i].last_used_idx << 16);
> +
> +		iowrite16(i + IFCVF_MSI_QUEUE_OFF, &cfg->queue_msix_vector);
> +		if (ioread16(&cfg->queue_msix_vector) ==
> +		    VIRTIO_MSI_NO_VECTOR) {
> +			IFC_ERR(ifcvf->dev,
> +				"No msix vector for queue %u.\n", i);
> +			return -1;
> +		}
> +
> +		iowrite16(1, &cfg->queue_enable);
> +	}
> +
> +	return 0;
> +}
> +
> +static void ifcvf_hw_disable(struct ifcvf_hw *hw)
> +{
> +	struct virtio_pci_common_cfg *cfg;
> +	u32 i;
> +
> +	cfg = hw->common_cfg;
> +	iowrite16(VIRTIO_MSI_NO_VECTOR, &cfg->msix_config);
> +
> +	for (i = 0; i < hw->nr_vring; i++) {
> +		iowrite16(i, &cfg->queue_select);
> +		iowrite16(0, &cfg->queue_enable);
> +		iowrite16(VIRTIO_MSI_NO_VECTOR, &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 -1;
> +
> +	if (ifcvf_hw_enable(hw) < 0)
> +		return -1;
> +
> +	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)
> +{
> +	iowrite16(qid, hw->notify_addr[qid]);
> +}
> +
> +u64 ifcvf_get_queue_notify_off(struct ifcvf_hw *hw, int qid)
> +{
> +	return (u8 *)hw->notify_addr[qid] -
> +		(u8 *)hw->mem_resource[hw->notify_bar].addr;
> +}
> diff --git a/drivers/vhost/ifcvf/ifcvf_base.h b/drivers/vhost/ifcvf/ifcvf_base.h
> new file mode 100644
> index 0000000..c97f0eb
> --- /dev/null
> +++ b/drivers/vhost/ifcvf/ifcvf_base.h
> @@ -0,0 +1,132 @@
> +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
> +/*
> + * Copyright (C) 2019 Intel Corporation.
> + */
> +
> +#ifndef _IFCVF_H_
> +#define _IFCVF_H_
> +
> +#include <linux/virtio_mdev_ops.h>
> +#include <linux/mdev.h>
> +#include <linux/pci.h>
> +#include <linux/pci_regs.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_MDEV_LIMIT	1
> +
> +/*
> + * Some ifcvf feature bits (currently bits 28 through 31) are
> + * reserved for the transport being used (eg. ifcvf_ring), the
> + * rest are per-device feature bits.
> + */
> +#define IFCVF_TRANSPORT_F_START 28
> +#define IFCVF_TRANSPORT_F_END   34
> +
> +#define IFC_SUPPORTED_FEATURES \
> +		((1ULL << VIRTIO_NET_F_MAC)			| \
> +		 (1ULL << VIRTIO_F_ANY_LAYOUT)			| \
> +		 (1ULL << VIRTIO_F_VERSION_1)			| \
> +		 (1ULL << VIRTIO_F_ORDER_PLATFORM)			| \

ACCESS_PLATFORM must be enabled for sure?


> +		 (1ULL << VIRTIO_NET_F_GUEST_ANNOUNCE)		| \
> +		 (1ULL << VIRTIO_NET_F_CTRL_VQ)			| \
> +		 (1ULL << VIRTIO_NET_F_STATUS)			| \
> +		 (1ULL << VIRTIO_NET_F_MRG_RXBUF)) /* not fully supported */
> +
> +//Not support MQ, only one queue pair for now.
> +#define IFCVF_MAX_QUEUE_PAIRS		1
> +#define IFCVF_MAX_QUEUES		2
> +
> +#define IFCVF_QUEUE_ALIGNMENT		PAGE_SIZE
> +
> +#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_32_BIT_MASK		0xffffffff
> +
> +#define IFC_ERR(dev, fmt, ...)	dev_err(dev, fmt, ##__VA_ARGS__)
> +#define IFC_DBG(dev, fmt, ...)	dev_dbg(dev, fmt, ##__VA_ARGS__)
> +#define IFC_INFO(dev, fmt, ...)	dev_info(dev, fmt, ##__VA_ARGS__)
> +
> +#define IFC_PRIVATE_TO_VF(adapter) \
> +	(&((struct ifcvf_adapter *)adapter)->vf)
> +
> +#define IFCVF_MAX_INTR (IFCVF_MAX_QUEUE_PAIRS * 2 + 1)
> +
> +struct ifcvf_net_config {
> +	u8    mac[6];
> +	u16   status;
> +	u16   max_virtqueue_pairs;
> +} __packed;
> +
> +struct ifcvf_pci_mem_resource {
> +	/* Physical address, 0 if not resource. */
> +	u64      phys_addr;
> +	/* Length of the resource. */
> +	u64      len;
> +	/* Virtual address, NULL when not mapped. */
> +	u8       *addr;
> +};
> +
> +struct vring_info {
> +	u64 desc;
> +	u64 avail;
> +	u64 used;
> +	u16 size;
> +	u16 last_avail_idx;
> +	u16 last_used_idx;
> +	bool ready;
> +	char msix_name[256];
> +	struct virtio_mdev_callback cb;
> +};
> +
> +struct ifcvf_hw {
> +	u8	*isr;
> +	u8	notify_bar;
> +	u8	*lm_cfg;
> +	u8	nr_vring;
> +	u16	*notify_base;
> +	u16	*notify_addr[IFCVF_MAX_QUEUE_PAIRS * 2];
> +	u32	notify_off_multiplier;
> +	u64	req_features;
> +	struct	virtio_pci_common_cfg *common_cfg;
> +	struct	ifcvf_net_config *net_cfg;
> +	struct	vring_info vring[IFCVF_MAX_QUEUE_PAIRS * 2];
> +	struct	ifcvf_pci_mem_resource mem_resource[IFCVF_PCI_MAX_RESOURCE];
> +};
> +
> +struct ifcvf_adapter {
> +	struct	device *dev;
> +	struct	mutex mdev_lock;
> +	int	mdev_count;
> +	int	vectors;
> +	struct	ifcvf_hw vf;
> +};
> +
> +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);
> +u8 ifcvf_get_linkstatus(struct ifcvf_hw *hw);
> +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);
> +
> +#endif /* _IFCVF_H_ */
> -- 
> 1.8.3.1

Re: [PATCH 1/2] IFC hardware operation layer

[Jason Wang]

On 2019/11/5 下午8:45, Michael S. Tsirkin wrote:
>> +
>> +#define IFC_SUPPORTED_FEATURES \
>> +		((1ULL << VIRTIO_NET_F_MAC)			| \
>> +		 (1ULL << VIRTIO_F_ANY_LAYOUT)			| \
>> +		 (1ULL << VIRTIO_F_VERSION_1)			| \
>> +		 (1ULL << VIRTIO_F_ORDER_PLATFORM)			| \
> ACCESS_PLATFORM must be enabled for sure?
>
>

I think so, consider vhost-mdev can filter it out right now.

Thanks

Re: [PATCH 1/2] IFC hardware operation layer

[Jason Wang]

On 2019/11/5 下午5:37, Zhu Lingshan wrote:
> This commit introduced ifcvf_base layer, which handles hardware
> operations and configurations.

It looks like the PCI layout is pretty similar to virtio. Can we reuse
e.g virtio_pci_modern_probe() (or helpers in virtio_pci_modern.c) to
do the probing?

>
> Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
> ---
>  drivers/vhost/ifcvf/ifcvf_base.c | 344 +++++++++++++++++++++++++++++++++++++++
>  drivers/vhost/ifcvf/ifcvf_base.h | 132 +++++++++++++++
>  2 files changed, 476 insertions(+)
>  create mode 100644 drivers/vhost/ifcvf/ifcvf_base.c
>  create mode 100644 drivers/vhost/ifcvf/ifcvf_base.h
>
> diff --git a/drivers/vhost/ifcvf/ifcvf_base.c b/drivers/vhost/ifcvf/ifcvf_base.c
> new file mode 100644
> index 0000000..0659f41
> --- /dev/null
> +++ b/drivers/vhost/ifcvf/ifcvf_base.c
> @@ -0,0 +1,344 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Copyright (C) 2019 Intel Corporation.
> + */
> +
> +#include "ifcvf_base.h"
> +
> +static void *get_cap_addr(struct ifcvf_hw *hw, struct virtio_pci_cap *cap)
> +{
> +	struct ifcvf_adapter *ifcvf;
> +	u32 length, offset;
> +	u8 bar;
> +
> +	length = le32_to_cpu(cap->length);
> +	offset = le32_to_cpu(cap->offset);
> +	bar = le32_to_cpu(cap->bar);
> +
> +	ifcvf = container_of(hw, struct ifcvf_adapter, vf);
> +
> +	if (bar >= IFCVF_PCI_MAX_RESOURCE) {
> +		IFC_DBG(ifcvf->dev,
> +			"Invalid bar number %u to get capabilities.\n", bar);
> +		return NULL;
> +	}
> +
> +	if (offset + length < offset) {

Can this really happen? Both offset and length are u32.

> +		IFC_DBG(ifcvf->dev, "offset(%u) + length(%u) overflows\n",
> +			offset, length);
> +		return NULL;
> +	}
> +
> +	if (offset + length > hw->mem_resource[cap->bar].len) {
> +		IFC_DBG(ifcvf->dev,
> +			"offset(%u) + len(%u) overflows bar%u to get capabilities.\n",
> +			offset, length, bar);
> +		return NULL;
> +	}
> +
> +	return hw->mem_resource[bar].addr + offset;

I don't see the initialization of mem_resource in the patch, I wonder
whether it's better to squash this patch just into patch 2.

> +}
> +
> +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 *dev)
> +{
> +	struct virtio_pci_cap cap;
> +	u16 notify_off;
> +	int ret;
> +	u8 pos;
> +	u32 i;
> +
> +	ret = pci_read_config_byte(dev, PCI_CAPABILITY_LIST, &pos);
> +
> +	if (ret < 0) {
> +		IFC_ERR(&dev->dev, "Failed to read PCI capability list.\n");
> +		return -EIO;
> +	}
> +
> +	while (pos) {
> +		ret = ifcvf_read_config_range(dev, (u32 *)&cap,
> +					      sizeof(cap), pos);
> +
> +		if (ret < 0) {
> +			IFC_ERR(&dev->dev, "Failed to get PCI capability at %x",
> +				pos);
> +			break;
> +		}
> +
> +		if (cap.cap_vndr != PCI_CAP_ID_VNDR)
> +			goto next;
> +
> +		IFC_DBG(&dev->dev, "read PCI config: config type: %u, PCI bar: %u,\
> +			 PCI bar offset: %u, PCI config len: %u.\n",
> +			cap.cfg_type, cap.bar, cap.offset, cap.length);
> +
> +		switch (cap.cfg_type) {
> +		case VIRTIO_PCI_CAP_COMMON_CFG:
> +			hw->common_cfg = get_cap_addr(hw, &cap);
> +			IFC_INFO(&dev->dev, "hw->common_cfg = %p.\n",
> +				 hw->common_cfg);
> +			break;
> +		case VIRTIO_PCI_CAP_NOTIFY_CFG:
> +			pci_read_config_dword(dev, pos + sizeof(cap),
> +					      &hw->notify_off_multiplier);
> +			hw->notify_bar = cap.bar;
> +			hw->notify_base = get_cap_addr(hw, &cap);
> +			IFC_INFO(&dev->dev, "hw->notify_base = %p.\n",
> +				 hw->notify_base);
> +			break;
> +		case VIRTIO_PCI_CAP_ISR_CFG:
> +			hw->isr = get_cap_addr(hw, &cap);
> +			IFC_INFO(&dev->dev, "hw->isr = %p.\n", hw->isr);
> +			break;
> +		case VIRTIO_PCI_CAP_DEVICE_CFG:
> +			hw->net_cfg = get_cap_addr(hw, &cap);
> +			IFC_INFO(&dev->dev, "hw->net_cfg = %p.\n", hw->net_cfg);
> +			break;

I think at least you can try to reuse e.g:
virtio_pci_find_capability() to aovid duplicating codes.

> +		}
> +next:
> +		pos = cap.cap_next;
> +	}
> +
> +	if (hw->common_cfg == NULL || hw->notify_base == NULL ||
> +	    hw->isr == NULL || hw->net_cfg == NULL) {
> +		IFC_DBG(&dev->dev, "Incomplete PCI capabilities.\n");
> +		return -1;

Maybe it's better to fail eailier.

> +	}
> +
> +	for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++) {
> +		iowrite16(i, &hw->common_cfg->queue_select);
> +		notify_off = ioread16(&hw->common_cfg->queue_notify_off);
> +		hw->notify_addr[i] = (void *)((u8 *)hw->notify_base +
> +				     notify_off * hw->notify_off_multiplier);

It might be better to store notify_addr inside the vring_info for
better locality.

> +	}
> +
> +	hw->lm_cfg = hw->mem_resource[IFCVF_LM_BAR].addr;
> +
> +	IFC_DBG(&dev->dev, "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)
> +{
> +	u8 old_gen, new_gen, status;
> +
> +	do {
> +		old_gen = ioread8(&hw->common_cfg->config_generation);
> +		status = ioread8(&hw->common_cfg->device_status);
> +		new_gen = ioread8(&hw->common_cfg->config_generation);

config generation should be only used for config access not status,
and even it did, it should be called from virtio core.

> +	} while (old_gen != new_gen);
> +
> +	return status;
> +}
> +
> +void ifcvf_set_status(struct ifcvf_hw *hw, u8 status)
> +{
> +	iowrite8(status, &hw->common_cfg->device_status);
> +}
> +
> +void ifcvf_reset(struct ifcvf_hw *hw)
> +{
> +	ifcvf_set_status(hw, 0);
> +	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 *cfg = hw->common_cfg;
> +	u32 features_lo, features_hi;
> +
> +	iowrite32(0, &cfg->device_feature_select);
> +	features_lo = ioread32(&cfg->device_feature);
> +
> +	iowrite32(1, &cfg->device_feature_select);
> +	features_hi = 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 ifcvf_net_config));
> +
> +	do {
> +		old_gen = ioread8(&hw->common_cfg->config_generation);

Same here, virtio core has did the call for generation, so no need do
do it again here.

> +		p = dst;
> +
> +		for (i = 0; i < length; i++)
> +			*p++ = ioread8((u8 *)hw->net_cfg + offset + i);
> +
> +		new_gen = 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 ifcvf_net_config));
> +
> +	for (i = 0; i < length; i++)
> +		iowrite8(*p++, (u8 *)hw->net_cfg + offset + i);
> +}
> +
> +static void ifcvf_set_features(struct ifcvf_hw *hw, u64 features)
> +{
> +	struct virtio_pci_common_cfg *cfg = hw->common_cfg;
> +
> +	iowrite32(0, &cfg->guest_feature_select);
> +	iowrite32(features & ((1ULL << 32) - 1), &cfg->guest_feature);

(u32)features ?

> +
> +	iowrite32(1, &cfg->guest_feature_select);
> +	iowrite32(features >> 32, &cfg->guest_feature);
> +}
> +
> +static int ifcvf_config_features(struct ifcvf_hw *hw)
> +{
> +	struct ifcvf_adapter *ifcvf;
> +
> +	ifcvf =	container_of(hw, struct ifcvf_adapter, vf);
> +	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)) {
> +		IFC_ERR(ifcvf->dev, "Failed to set FEATURES_OK status\n");
> +		return -EIO;
> +	}
> +
> +	return 0;
> +}
> +
> +void io_write64_twopart(u64 val, u32 *lo, u32 *hi)
> +{
> +	iowrite32(val & ((1ULL << 32) - 1), lo);
> +	iowrite32(val >> 32, hi);
> +}
> +
> +static int ifcvf_hw_enable(struct ifcvf_hw *hw)
> +{
> +	struct virtio_pci_common_cfg *cfg;
> +	struct ifcvf_adapter *ifcvf;
> +	u8 *lm_cfg;
> +	u32 i;
> +
> +	ifcvf = container_of(hw, struct ifcvf_adapter, vf);
> +	cfg = hw->common_cfg;
> +	lm_cfg = hw->lm_cfg;
> +	iowrite16(IFCVF_MSI_CONFIG_OFF, &cfg->msix_config);
> +
> +	if (ioread16(&cfg->msix_config) == VIRTIO_MSI_NO_VECTOR) {
> +		IFC_ERR(ifcvf->dev, "No msix vector for device config.\n");
> +		return -1;
> +	}
> +
> +	for (i = 0; i < hw->nr_vring; i++) {
> +		iowrite16(i, &cfg->queue_select);
> +		io_write64_twopart(hw->vring[i].desc, &cfg->queue_desc_lo,
> +				&cfg->queue_desc_hi);
> +		io_write64_twopart(hw->vring[i].avail, &cfg->queue_avail_lo,
> +				&cfg->queue_avail_hi);
> +		io_write64_twopart(hw->vring[i].used, &cfg->queue_used_lo,
> +				&cfg->queue_used_hi);
> +		iowrite16(hw->vring[i].size, &cfg->queue_size);
> +
> +		*(u32 *)(lm_cfg + IFCVF_LM_RING_STATE_OFFSET +
> +				(i / 2) * IFCVF_LM_CFG_SIZE + (i % 2) * 4) =
> +			(u32)hw->vring[i].last_avail_idx |
> +			((u32)hw->vring[i].last_used_idx << 16);

As pointed out by Michael, it's better to formalize lm_cfg as a
structure instead of doing math here.

> +
> +		iowrite16(i + IFCVF_MSI_QUEUE_OFF, &cfg->queue_msix_vector);
> +		if (ioread16(&cfg->queue_msix_vector) ==
> +		    VIRTIO_MSI_NO_VECTOR) {
> +			IFC_ERR(ifcvf->dev,
> +				"No msix vector for queue %u.\n", i);
> +			return -1;
> +		}
> +
> +		iowrite16(1, &cfg->queue_enable);

This queue_enable should be done through set_vq_ready() from virtio core.

> +	}
> +
> +	return 0;
> +}
> +
> +static void ifcvf_hw_disable(struct ifcvf_hw *hw)
> +{
> +	struct virtio_pci_common_cfg *cfg;
> +	u32 i;
> +
> +	cfg = hw->common_cfg;
> +	iowrite16(VIRTIO_MSI_NO_VECTOR, &cfg->msix_config);
> +
> +	for (i = 0; i < hw->nr_vring; i++) {
> +		iowrite16(i, &cfg->queue_select);
> +		iowrite16(0, &cfg->queue_enable);
> +		iowrite16(VIRTIO_MSI_NO_VECTOR, &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 -1;

It's better to set status to CONFIG_S_FAILED when fail.

> +
> +	if (ifcvf_hw_enable(hw) < 0)
> +		return -1;
> +
> +	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)
> +{
> +	iowrite16(qid, hw->notify_addr[qid]);
> +}
> +
> +u64 ifcvf_get_queue_notify_off(struct ifcvf_hw *hw, int qid)
> +{
> +	return (u8 *)hw->notify_addr[qid] -
> +		(u8 *)hw->mem_resource[hw->notify_bar].addr;
> +}
> diff --git a/drivers/vhost/ifcvf/ifcvf_base.h b/drivers/vhost/ifcvf/ifcvf_base.h
> new file mode 100644
> index 0000000..c97f0eb
> --- /dev/null
> +++ b/drivers/vhost/ifcvf/ifcvf_base.h
> @@ -0,0 +1,132 @@
> +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
> +/*
> + * Copyright (C) 2019 Intel Corporation.
> + */
> +
> +#ifndef _IFCVF_H_
> +#define _IFCVF_H_
> +
> +#include <linux/virtio_mdev_ops.h>
> +#include <linux/mdev.h>
> +#include <linux/pci.h>
> +#include <linux/pci_regs.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_MDEV_LIMIT	1
> +
> +/*
> + * Some ifcvf feature bits (currently bits 28 through 31) are
> + * reserved for the transport being used (eg. ifcvf_ring), the
> + * rest are per-device feature bits.
> + */
> +#define IFCVF_TRANSPORT_F_START 28
> +#define IFCVF_TRANSPORT_F_END   34
> +
> +#define IFC_SUPPORTED_FEATURES \
> +		((1ULL << VIRTIO_NET_F_MAC)			| \
> +		 (1ULL << VIRTIO_F_ANY_LAYOUT)			| \
> +		 (1ULL << VIRTIO_F_VERSION_1)			| \
> +		 (1ULL << VIRTIO_F_ORDER_PLATFORM)			| \
> +		 (1ULL << VIRTIO_NET_F_GUEST_ANNOUNCE)		| \
> +		 (1ULL << VIRTIO_NET_F_CTRL_VQ)			| \
> +		 (1ULL << VIRTIO_NET_F_STATUS)			| \
> +		 (1ULL << VIRTIO_NET_F_MRG_RXBUF)) /* not fully supported */

If it was not fully supported, we need to remove it.

> +
> +//Not support MQ, only one queue pair for now.
> +#define IFCVF_MAX_QUEUE_PAIRS		1
> +#define IFCVF_MAX_QUEUES		2
> +
> +#define IFCVF_QUEUE_ALIGNMENT		PAGE_SIZE
> +
> +#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_32_BIT_MASK		0xffffffff
> +
> +#define IFC_ERR(dev, fmt, ...)	dev_err(dev, fmt, ##__VA_ARGS__)
> +#define IFC_DBG(dev, fmt, ...)	dev_dbg(dev, fmt, ##__VA_ARGS__)
> +#define IFC_INFO(dev, fmt, ...)	dev_info(dev, fmt, ##__VA_ARGS__)
> +
> +#define IFC_PRIVATE_TO_VF(adapter) \
> +	(&((struct ifcvf_adapter *)adapter)->vf)
> +
> +#define IFCVF_MAX_INTR (IFCVF_MAX_QUEUE_PAIRS * 2 + 1)
> +
> +struct ifcvf_net_config {
> +	u8    mac[6];
> +	u16   status;
> +	u16   max_virtqueue_pairs;
> +} __packed;

Why not just use virtio_net_config?

> +
> +struct ifcvf_pci_mem_resource {
> +	/* Physical address, 0 if not resource. */
> +	u64      phys_addr;
> +	/* Length of the resource. */
> +	u64      len;
> +	/* Virtual address, NULL when not mapped. */
> +	u8       *addr;
> +};
> +
> +struct vring_info {
> +	u64 desc;
> +	u64 avail;
> +	u64 used;
> +	u16 size;
> +	u16 last_avail_idx;
> +	u16 last_used_idx;
> +	bool ready;
> +	char msix_name[256];
> +	struct virtio_mdev_callback cb;
> +};
> +
> +struct ifcvf_hw {
> +	u8	*isr;
> +	u8	notify_bar;
> +	u8	*lm_cfg;
> +	u8	nr_vring;
> +	u16	*notify_base;
> +	u16	*notify_addr[IFCVF_MAX_QUEUE_PAIRS * 2];
> +	u32	notify_off_multiplier;
> +	u64	req_features;
> +	struct	virtio_pci_common_cfg *common_cfg;
> +	struct	ifcvf_net_config *net_cfg;
> +	struct	vring_info vring[IFCVF_MAX_QUEUE_PAIRS * 2];
> +	struct	ifcvf_pci_mem_resource mem_resource[IFCVF_PCI_MAX_RESOURCE];
> +};

It's better to add comments to explain each field.

> +
> +struct ifcvf_adapter {
> +	struct	device *dev;
> +	struct	mutex mdev_lock;
> +	int	mdev_count;
> +	int	vectors;
> +	struct	ifcvf_hw vf;
> +};
> +
> +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);
> +u8 ifcvf_get_linkstatus(struct ifcvf_hw *hw);
> +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);
> +
> +#endif /* _IFCVF_H_ */
> -- 
> 1.8.3.1
>

Re: [PATCH 2/2] IFC VDPA layer

[Jason Wang]

----- Original Message -----
> This commit introduced IFC operations for vdpa, which complys to
> virtio_mdev and vhost_mdev interfaces, handles IFC VF
> initialization, configuration and removal.
> 
> Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
> ---
>  drivers/vhost/ifcvf/ifcvf_main.c | 605
>  +++++++++++++++++++++++++++++++++++++++
>  1 file changed, 605 insertions(+)
>  create mode 100644 drivers/vhost/ifcvf/ifcvf_main.c
> 
> diff --git a/drivers/vhost/ifcvf/ifcvf_main.c
> b/drivers/vhost/ifcvf/ifcvf_main.c
> new file mode 100644
> index 0000000..7165457
> --- /dev/null
> +++ b/drivers/vhost/ifcvf/ifcvf_main.c
> @@ -0,0 +1,605 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Copyright (C) 2019 Intel Corporation.
> + */
> +
> +#include <linux/interrupt.h>
> +#include <linux/module.h>
> +#include <linux/mdev.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 struct ifcvf_hw *mdev_to_vf(struct mdev_device *mdev)
> +{
> +	struct ifcvf_asapter *adapter = mdev_get_drvdata(mdev);
> +	struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(adapter);
> +
> +	return vf;
> +}
> +
> +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 u64 ifcvf_mdev_get_features(struct mdev_device *mdev)
> +{
> +	struct ifcvf_hw *vf = mdev_to_vf(mdev);
> +
> +	return ifcvf_get_features(vf);
> +}
> +
> +static int ifcvf_mdev_set_features(struct mdev_device *mdev, u64 features)
> +{
> +	struct ifcvf_hw *vf = mdev_to_vf(mdev);
> +
> +	vf->req_features = features;
> +
> +	return 0;
> +}
> +
> +static u64 ifcvf_mdev_get_vq_state(struct mdev_device *mdev, u16 qid)
> +{
> +	struct ifcvf_hw *vf = mdev_to_vf(mdev);
> +	u16 last_avail_idx;
> +
> +	last_avail_idx = *(u16 *)(vf->lm_cfg + IFCVF_LM_RING_STATE_OFFSET +
> +			 (qid / 2) * IFCVF_LM_CFG_SIZE + (qid % 2) * 4);
> +

Similar to the comment of previous patch, it's better to have a
structure for lm_cfg.

> +	return last_avail_idx;
> +}
> +
> +static int ifcvf_mdev_set_vq_state(struct mdev_device *mdev, u16 qid, u64
> num)
> +{
> +	struct ifcvf_hw *vf = mdev_to_vf(mdev);
> +
> +	vf->vring[qid].last_avail_idx = num;
> +
> +	return 0;
> +}
> +
> +static int ifcvf_mdev_set_vq_address(struct mdev_device *mdev, u16 idx,
> +				     u64 desc_area, u64 driver_area,
> +				     u64 device_area)
> +{
> +	struct ifcvf_hw *vf = mdev_to_vf(mdev);
> +
> +	vf->vring[idx].desc = desc_area;
> +	vf->vring[idx].avail = driver_area;
> +	vf->vring[idx].used = device_area;
> +
> +	return 0;
> +}
> +
> +static void ifcvf_mdev_set_vq_num(struct mdev_device *mdev, u16 qid, u32
> num)
> +{
> +	struct ifcvf_hw *vf = mdev_to_vf(mdev);
> +
> +	vf->vring[qid].size = num;
> +}
> +
> +static void ifcvf_mdev_set_vq_ready(struct mdev_device *mdev,
> +				    u16 qid, bool ready)
> +{
> +	struct ifcvf_hw *vf = mdev_to_vf(mdev);
> +
> +	vf->vring[qid].ready = ready;

There should be a "iowrite16(1, &cfg->queue_enable)" here. And there's
probably no need to store ready in vring in this case.

> +}
> +
> +static bool ifcvf_mdev_get_vq_ready(struct mdev_device *mdev, u16 qid)
> +{
> +	struct ifcvf_hw *vf = mdev_to_vf(mdev);
> +
> +	return vf->vring[qid].ready;

And the status should be read from cfg->queue_enable.

> +}
> +
> +static void ifcvf_mdev_set_vq_cb(struct mdev_device *mdev, u16 idx,
> +				 struct virtio_mdev_callback *cb)
> +{
> +	struct ifcvf_hw *vf = mdev_to_vf(mdev);
> +
> +	vf->vring[idx].cb = *cb;
> +}
> +
> +static void ifcvf_mdev_kick_vq(struct mdev_device *mdev, u16 idx)
> +{
> +	struct ifcvf_hw *vf = mdev_to_vf(mdev);
> +
> +	ifcvf_notify_queue(vf, idx);
> +}
> +
> +static u8 ifcvf_mdev_get_status(struct mdev_device *mdev)
> +{
> +	struct ifcvf_hw *vf = mdev_to_vf(mdev);
> +
> +	return ifcvf_get_status(vf);
> +}
> +
> +static u32 ifcvf_mdev_get_generation(struct mdev_device *mdev)
> +{
> +	struct ifcvf_hw *vf = mdev_to_vf(mdev);
> +
> +	return ioread8(&vf->common_cfg->config_generation);
> +}
> +
> +static u32 ifcvf_mdev_get_device_id(struct mdev_device *mdev)
> +{
> +	return VIRTIO_ID_NET;
> +}
> +
> +static u32 ifcvf_mdev_get_vendor_id(struct mdev_device *mdev)
> +{
> +	return IFCVF_VENDOR_ID;
> +}
> +
> +static u16 ifcvf_mdev_get_vq_align(struct mdev_device *mdev)
> +{
> +	return IFCVF_QUEUE_ALIGNMENT;
> +}
> +
> +static u64 ifcvf_mdev_get_mdev_features(struct mdev_device *mdev)
> +{
> +	return VIRTIO_MDEV_F_VERSION_1;
> +}

We've decide to remove this API.

> +
> +static int ifcvf_start_datapath(void *private)
> +{
> +	struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(private);
> +	struct ifcvf_adapter *ifcvf;
> +	int i, ret = 0;
> +
> +	ifcvf = container_of(vf, struct ifcvf_adapter, vf);
> +
> +	for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++) {
> +		if (!vf->vring[i].ready) {
> +			IFC_ERR(ifcvf->dev,
> +				"Failed to start datapath, vring %d not ready.\n", i);
> +			return -EINVAL;
> +		}

This should be not related. Driver can choose to not start a virtqueue.

> +
> +		if (!vf->vring[i].size) {
> +			IFC_ERR(ifcvf->dev,
> +				"Failed to start datapath, vring %d size is zero.\n", i);
> +			return -EINVAL;
> +		}
> +
> +		if (!vf->vring[i].desc || !vf->vring[i].avail ||
> +			!vf->vring[i].used) {
> +			IFC_ERR(ifcvf->dev,
> +				"Failed to start datapath, "
> +				"invaild value for vring %d desc,"
> +				"avail_idx or usex_idx.\n", i);
> +			return -EINVAL;
> +		}
> +	}
> +
> +	vf->nr_vring = i;
> +	ret = ifcvf_start_hw(vf);

So basically there's no need for ifcvf_start_hw() to care about vq
enablement, virtio core will take care of that through set_vq_ready().

> +
> +	return ret;
> +}
> +
> +static int ifcvf_stop_datapath(void *private)
> +{
> +	struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(private);
> +	int i;
> +
> +	for (i = 0; i < IFCVF_MAX_QUEUES; 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 = IFC_PRIVATE_TO_VF(adapter);
> +	struct virtio_pci_common_cfg *cfg;
> +	u8 *lm_cfg;
> +	int i;
> +
> +	cfg = vf->common_cfg;
> +	lm_cfg = vf->lm_cfg;
> +
> +	for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++) {
> +		vf->vring[i].last_used_idx = 0;
> +		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->cb.callback = NULL;
> +		vf->vring->cb.private = NULL;
> +
> +	}
> +
> +	ifcvf_reset(vf);

So virtio-pci call vp_synchornize_vectors(), do need someting similar
here (I mean in ifcvf_reset())?

> +}
> +
> +static void ifcvf_mdev_set_status(struct mdev_device *mdev, u8 status)
> +{
> +	struct ifcvf_adapter *adapter = mdev_get_drvdata(mdev);
> +	struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(adapter);
> +	int ret = 0;
> +
> +	if (status == 0) {
> +		ifcvf_stop_datapath(adapter);
> +		ifcvf_reset_vring(adapter);
> +		return;
> +	}
> +
> +	if (status & VIRTIO_CONFIG_S_DRIVER_OK) {
> +		ret = ifcvf_start_datapath(adapter);

If device support VIRTIO_CONFIG_S_DRIVER_OK, having something like
start_datapath here looks wired.

If it just to setup the virtqueue etc, can we simply move them to e.g
set_vq_num, set_vq_address, etc?

> +
> +		if (ret)
> +			IFC_ERR(adapter->dev, "Failed to set mdev status %u.\n",
> +				status);
> +	}
> +
> +	ifcvf_set_status(vf, status);
> +}
> +
> +static u16 ifcvf_mdev_get_vq_num_max(struct mdev_device *mdev)
> +{
> +	struct ifcvf_hw *vf = mdev_to_vf(mdev);
> +
> +	return vf->vring[0].size;

It looks to me the only case that size is set is from
ifcvf_mdev_set_vq_num()? So I don't get how is this supposed to
work. I belive this should be a query for the hardware or a at least a
macro?


> +}
> +static void ifcvf_mdev_get_config(struct mdev_device *mdev, unsigned int
> offset,
> +			     void *buf, unsigned int len)
> +{
> +	struct ifcvf_hw *vf = mdev_to_vf(mdev);
> +
> +	WARN_ON(offset + len > sizeof(struct ifcvf_net_config));
> +	ifcvf_read_net_config(vf, offset, buf, len);
> +}
> +
> +static void ifcvf_mdev_set_config(struct mdev_device *mdev, unsigned int
> offset,
> +			     const void *buf, unsigned int len)
> +{
> +	struct ifcvf_hw *vf = mdev_to_vf(mdev);
> +
> +	WARN_ON(offset + len > sizeof(struct ifcvf_net_config));
> +	ifcvf_write_net_config(vf, offset, buf, len);
> +}
> +
> +static struct virtio_mdev_device_ops ifc_mdev_ops = {
> +	.get_features  = ifcvf_mdev_get_features,
> +	.set_features  = ifcvf_mdev_set_features,
> +	.get_status    = ifcvf_mdev_get_status,
> +	.set_status    = ifcvf_mdev_set_status,
> +	.get_vq_num_max = ifcvf_mdev_get_vq_num_max,
> +	.get_vq_state   = ifcvf_mdev_get_vq_state,
> +	.set_vq_state   = ifcvf_mdev_set_vq_state,
> +	.set_vq_cb      = ifcvf_mdev_set_vq_cb,
> +	.set_vq_ready   = ifcvf_mdev_set_vq_ready,
> +	.get_vq_ready	= ifcvf_mdev_get_vq_ready,
> +	.set_vq_num     = ifcvf_mdev_set_vq_num,
> +	.set_vq_address = ifcvf_mdev_set_vq_address,
> +	.kick_vq        = ifcvf_mdev_kick_vq,
> +	.get_generation	= ifcvf_mdev_get_generation,
> +	.get_device_id	= ifcvf_mdev_get_device_id,
> +	.get_vendor_id	= ifcvf_mdev_get_vendor_id,
> +	.get_vq_align	= ifcvf_mdev_get_vq_align,
> +	.get_config	= ifcvf_mdev_get_config,
> +	.set_config	= ifcvf_mdev_set_config,
> +	.get_mdev_features = ifcvf_mdev_get_mdev_features,

set_config_cb needs to be implemented since you claim to support VIRTIO_NET_F_STATUS.

> +};
> +
> +static int ifcvf_init_msix(struct ifcvf_adapter *adapter)
> +{
> +	struct pci_dev *pdev = to_pci_dev(adapter->dev);
> +	struct ifcvf_hw *vf = &adapter->vf;
> +	int vector, i, ret, irq;
> +
> +	ret = pci_alloc_irq_vectors(pdev, IFCVF_MAX_INTR,
> +				    IFCVF_MAX_INTR, PCI_IRQ_MSIX);
> +	if (ret < 0) {
> +		IFC_ERR(adapter->dev, "Failed to alloc irq vectors.\n");
> +		return ret;
> +	}
> +
> +	for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++) {
> +		vector = i + IFCVF_MSI_QUEUE_OFF;
> +		irq = pci_irq_vector(pdev, vector);
> +		ret = request_irq(irq, ifcvf_intr_handler, 0,
> +				pci_name(pdev), &vf->vring[i]);
> +		if (ret) {
> +			IFC_ERR(adapter->dev,
> +				"Failed to request irq for vq %d.\n", i);
> +			return ret;
> +		}
> +	}

Need allocate config interrupt here as well.

> +
> +	return 0;
> +}
> +
> +static void ifcvf_destroy_adapter(struct ifcvf_adapter *adapter)
> +{
> +	struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(adapter);
> +	struct pci_dev *pdev = to_pci_dev(adapter->dev);
> +	int i, vector, irq;
> +
> +	for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++) {
> +		vector = i + IFCVF_MSI_QUEUE_OFF;
> +		irq = pci_irq_vector(pdev, vector);
> +		free_irq(irq, &vf->vring[i]);
> +	}
> +}
> +
> +static ssize_t name_show(struct kobject *kobj, struct device *dev, char
> *buf)
> +{
> +	const char *name = "vhost accelerator (virtio ring compatible)";
> +

I believe something like "IFCVF vhost/virtio accelerator" is better?

> +	return sprintf(buf, "%s\n", name);
> +}
> +MDEV_TYPE_ATTR_RO(name);
> +
> +static ssize_t device_api_show(struct kobject *kobj, struct device *dev,
> +			       char *buf)
> +{
> +	return sprintf(buf, "%s\n", VIRTIO_MDEV_DEVICE_API_STRING);
> +}
> +MDEV_TYPE_ATTR_RO(device_api);
> +
> +static ssize_t available_instances_show(struct kobject *kobj,
> +					struct device *dev, char *buf)
> +{
> +	struct pci_dev *pdev;
> +	struct ifcvf_adapter *adapter;
> +
> +	pdev = to_pci_dev(dev);
> +	adapter = pci_get_drvdata(pdev);
> +
> +	return sprintf(buf, "%d\n", adapter->mdev_count);
> +}
> +
> +MDEV_TYPE_ATTR_RO(available_instances);
> +
> +static ssize_t type_show(struct kobject *kobj,
> +			struct device *dev, char *buf)
> +{
> +	return sprintf(buf, "%s\n", "net");
> +}
> +
> +MDEV_TYPE_ATTR_RO(type);
> +
> +
> +static struct attribute *mdev_types_attrs[] = {
> +	&mdev_type_attr_name.attr,
> +	&mdev_type_attr_device_api.attr,
> +	&mdev_type_attr_available_instances.attr,
> +	&mdev_type_attr_type.attr,
> +	NULL,
> +};
> +
> +static struct attribute_group mdev_type_group_virtio = {
> +	.name  = "virtio_mdev",
> +	.attrs = mdev_types_attrs,
> +};
> +
> +static struct attribute_group mdev_type_group_vhost = {
> +	.name  = "vhost_mdev",
> +	.attrs = mdev_types_attrs,
> +};
> +
> +static struct attribute_group *mdev_type_groups[] = {
> +	&mdev_type_group_virtio,
> +	&mdev_type_group_vhost,
> +	NULL,
> +};
> +
> +const struct attribute_group *mdev_dev_groups[] = {
> +	NULL,
> +};
> +
> +static int ifcvf_mdev_create(struct kobject *kobj, struct mdev_device *mdev)
> +{
> +	struct device *dev = mdev_parent_dev(mdev);
> +	struct pci_dev *pdev = to_pci_dev(dev);
> +	struct ifcvf_adapter *adapter = pci_get_drvdata(pdev);
> +	int ret = 0;
> +
> +	mutex_lock(&adapter->mdev_lock);
> +
> +	if (adapter->mdev_count < IFCVF_MDEV_LIMIT) {
> +		IFC_ERR(&pdev->dev,
> +			"Can not create mdev, reached limitation %d.\n",
> +			IFCVF_MDEV_LIMIT);
> +		ret = -EINVAL;
> +		goto out;
> +	}
> +
> +	if (!strcmp(kobj->name, "ifcvf-virtio_mdev"))
> +		mdev_set_virtio_ops(mdev, &ifc_mdev_ops);
> +
> +	if (!strcmp(kobj->name, "ifcvf-vhost_mdev"))
> +		mdev_set_vhost_ops(mdev, &ifc_mdev_ops);
> +
> +	mdev_set_drvdata(mdev, adapter);
> +	mdev_set_iommu_device(mdev_dev(mdev), dev);
> +	adapter->mdev_count--;
> +
> +out:
> +	mutex_unlock(&adapter->mdev_lock);
> +	return ret;
> +}
> +
> +static int ifcvf_mdev_remove(struct mdev_device *mdev)
> +{
> +	struct device *dev = mdev_parent_dev(mdev);
> +	struct pci_dev *pdev = to_pci_dev(dev);
> +	struct ifcvf_adapter *adapter = pci_get_drvdata(pdev);
> +
> +	mutex_lock(&adapter->mdev_lock);
> +	adapter->mdev_count++;
> +	mutex_unlock(&adapter->mdev_lock);
> +
> +	return 0;
> +}
> +
> +static struct mdev_parent_ops ifcvf_mdev_fops = {
> +	.owner			= THIS_MODULE,
> +	.supported_type_groups	= mdev_type_groups,
> +	.mdev_attr_groups	= mdev_dev_groups,
> +	.create			= ifcvf_mdev_create,
> +	.remove			= ifcvf_mdev_remove,
> +};
> +
> +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, i;
> +
> +	adapter = kzalloc(sizeof(struct ifcvf_adapter), GFP_KERNEL);
> +
> +	if (adapter == NULL) {
> +		ret = -ENOMEM;
> +		goto fail;
> +	}
> +
> +	mutex_init(&adapter->mdev_lock);
> +	adapter->mdev_count = IFCVF_MDEV_LIMIT;
> +	adapter->dev = dev;
> +	pci_set_drvdata(pdev, adapter);
> +	ret = pci_enable_device(pdev);
> +
> +	if (ret) {
> +		IFC_ERR(adapter->dev, "Failed to enable device.\n");
> +		goto free_adapter;
> +	}
> +
> +	ret = pci_request_regions(pdev, IFCVF_DRIVER_NAME);
> +
> +	if (ret) {
> +		IFC_ERR(adapter->dev, "Failed to request MMIO region.\n");
> +		goto disable_device;
> +	}
> +
> +	pci_set_master(pdev);
> +	ret = ifcvf_init_msix(adapter);
> +
> +	if (ret) {
> +		IFC_ERR(adapter->dev, "Failed to initialize MSIX.\n");
> +		goto free_msix;
> +	}
> +
> +	vf = &adapter->vf;
> +
> +	for (i = 0; i < IFCVF_PCI_MAX_RESOURCE; i++) {
> +		vf->mem_resource[i].phys_addr = pci_resource_start(pdev, i);
> +		vf->mem_resource[i].len = pci_resource_len(pdev, i);
> +		if (!vf->mem_resource[i].len) {
> +			vf->mem_resource[i].addr = NULL;
> +			continue;
> +		}
> +
> +		vf->mem_resource[i].addr = pci_iomap_range(pdev, i, 0,
> +				vf->mem_resource[i].len);
> +		if (!vf->mem_resource[i].addr) {
> +			IFC_ERR(adapter->dev, "Failed to map IO resource %d\n",
> +				i);
> +			ret = -1;
> +			goto free_msix;
> +		}
> +	}
> +
> +	if (ifcvf_init_hw(vf, pdev) < 0) {
> +		ret = -1;
> +		goto destroy_adapter;
> +	}
> +
> +	ret = mdev_register_device(dev, &ifcvf_mdev_fops);
> +
> +	if (ret) {
> +		IFC_ERR(adapter->dev,  "Failed to register mdev device\n");
> +		goto destroy_adapter;
> +	}
> +
> +	return 0;
> +
> +destroy_adapter:
> +	ifcvf_destroy_adapter(adapter);
> +free_msix:
> +	pci_free_irq_vectors(pdev);
> +	pci_release_regions(pdev);
> +disable_device:
> +	pci_disable_device(pdev);
> +free_adapter:
> +	kfree(adapter);
> +fail:
> +	return ret;
> +}
> +
> +static void ifcvf_remove(struct pci_dev *pdev)
> +{
> +	struct ifcvf_adapter *adapter = pci_get_drvdata(pdev);
> +	struct device *dev = &pdev->dev;
> +	struct ifcvf_hw *vf;
> +	int i;
> +
> +	mdev_unregister_device(dev);
> +
> +	vf = &adapter->vf;
> +	for (i = 0; i < IFCVF_PCI_MAX_RESOURCE; i++) {
> +		if (vf->mem_resource[i].addr) {
> +			pci_iounmap(pdev, vf->mem_resource[i].addr);
> +			vf->mem_resource[i].addr = NULL;
> +		}
> +	}
> +
> +	ifcvf_destroy_adapter(adapter);
> +	pci_free_irq_vectors(pdev);
> +	pci_release_regions(pdev);
> +	pci_disable_device(pdev);
> +	kfree(adapter);
> +}
> +
> +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,
> +};
> +
> +static int __init ifcvf_init_module(void)
> +{
> +	int ret;
> +
> +	ret = pci_register_driver(&ifcvf_driver);
> +	return ret;
> +}
> +
> +static void __exit ifcvf_exit_module(void)
> +{
> +	pci_unregister_driver(&ifcvf_driver);
> +}

You probably can do something simpler thorugh module_pci_driver().

Thanks

> +
> +module_init(ifcvf_init_module);
> +module_exit(ifcvf_exit_module);
> +
> +MODULE_LICENSE("GPL v2");
> +MODULE_VERSION(VERSION_STRING);
> +MODULE_AUTHOR(DRIVER_AUTHOR);
> --
> 1.8.3.1
> 
> 

Re: [PATCH 1/2] IFC hardware operation layer

[Zhu Lingshan]

On 11/5/2019 8:45 PM, Michael S. Tsirkin wrote:
> On Tue, Nov 05, 2019 at 05:37:39PM +0800, Zhu Lingshan wrote:
>> This commit introduced ifcvf_base layer, which handles hardware
>> operations and configurations.
>>
>> Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
>> ---
>>   drivers/vhost/ifcvf/ifcvf_base.c | 344 +++++++++++++++++++++++++++++++++++++++
>>   drivers/vhost/ifcvf/ifcvf_base.h | 132 +++++++++++++++
>>   2 files changed, 476 insertions(+)
>>   create mode 100644 drivers/vhost/ifcvf/ifcvf_base.c
>>   create mode 100644 drivers/vhost/ifcvf/ifcvf_base.h
>>
>> diff --git a/drivers/vhost/ifcvf/ifcvf_base.c b/drivers/vhost/ifcvf/ifcvf_base.c
>> new file mode 100644
>> index 0000000..0659f41
>> --- /dev/null
>> +++ b/drivers/vhost/ifcvf/ifcvf_base.c
>> @@ -0,0 +1,344 @@
>> +// SPDX-License-Identifier: GPL-2.0-only
>> +/*
>> + * Copyright (C) 2019 Intel Corporation.
>> + */
>> +
>> +#include "ifcvf_base.h"
>> +
>> +static void *get_cap_addr(struct ifcvf_hw *hw, struct virtio_pci_cap *cap)
>> +{
>> +	struct ifcvf_adapter *ifcvf;
>> +	u32 length, offset;
>> +	u8 bar;
>> +
>> +	length = le32_to_cpu(cap->length);
>> +	offset = le32_to_cpu(cap->offset);
>> +	bar = le32_to_cpu(cap->bar);
>> +
>> +	ifcvf = container_of(hw, struct ifcvf_adapter, vf);
>> +
>> +	if (bar >= IFCVF_PCI_MAX_RESOURCE) {
>> +		IFC_DBG(ifcvf->dev,
>> +			"Invalid bar number %u to get capabilities.\n", bar);
>> +		return NULL;
>> +	}
>> +
>> +	if (offset + length < offset) {
>> +		IFC_DBG(ifcvf->dev, "offset(%u) + length(%u) overflows\n",
>> +			offset, length);
>> +		return NULL;
>> +	}
>> +
>> +	if (offset + length > hw->mem_resource[cap->bar].len) {
>> +		IFC_DBG(ifcvf->dev,
>> +			"offset(%u) + len(%u) overflows bar%u to get capabilities.\n",
>> +			offset, length, bar);
>> +		return NULL;
>> +	}
>> +
>> +	return hw->mem_resource[bar].addr + offset;
>> +}
>> +
>> +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 *dev)
>> +{
>> +	struct virtio_pci_cap cap;
>> +	u16 notify_off;
>> +	int ret;
>> +	u8 pos;
>> +	u32 i;
>> +
>> +	ret = pci_read_config_byte(dev, PCI_CAPABILITY_LIST, &pos);
>> +
>> +	if (ret < 0) {
>> +		IFC_ERR(&dev->dev, "Failed to read PCI capability list.\n");
>> +		return -EIO;
>> +	}
>> +
>> +	while (pos) {
>> +		ret = ifcvf_read_config_range(dev, (u32 *)&cap,
>> +					      sizeof(cap), pos);
>> +
>> +		if (ret < 0) {
>> +			IFC_ERR(&dev->dev, "Failed to get PCI capability at %x",
>> +				pos);
>> +			break;
>> +		}
>> +
>> +		if (cap.cap_vndr != PCI_CAP_ID_VNDR)
>> +			goto next;
>> +
>> +		IFC_DBG(&dev->dev, "read PCI config: config type: %u, PCI bar: %u,\
>> +			 PCI bar offset: %u, PCI config len: %u.\n",
>> +			cap.cfg_type, cap.bar, cap.offset, cap.length);
>> +
>> +		switch (cap.cfg_type) {
>> +		case VIRTIO_PCI_CAP_COMMON_CFG:
>> +			hw->common_cfg = get_cap_addr(hw, &cap);
>> +			IFC_INFO(&dev->dev, "hw->common_cfg = %p.\n",
>> +				 hw->common_cfg);
>> +			break;
>> +		case VIRTIO_PCI_CAP_NOTIFY_CFG:
>> +			pci_read_config_dword(dev, pos + sizeof(cap),
>> +					      &hw->notify_off_multiplier);
>> +			hw->notify_bar = cap.bar;
>> +			hw->notify_base = get_cap_addr(hw, &cap);
>> +			IFC_INFO(&dev->dev, "hw->notify_base = %p.\n",
>> +				 hw->notify_base);
>> +			break;
>> +		case VIRTIO_PCI_CAP_ISR_CFG:
>> +			hw->isr = get_cap_addr(hw, &cap);
>> +			IFC_INFO(&dev->dev, "hw->isr = %p.\n", hw->isr);
>> +			break;
>> +		case VIRTIO_PCI_CAP_DEVICE_CFG:
>> +			hw->net_cfg = get_cap_addr(hw, &cap);
>> +			IFC_INFO(&dev->dev, "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) {
>> +		IFC_DBG(&dev->dev, "Incomplete PCI capabilities.\n");
>> +		return -1;
>> +	}
>> +
>> +	for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++) {
>> +		iowrite16(i, &hw->common_cfg->queue_select);
>> +		notify_off = ioread16(&hw->common_cfg->queue_notify_off);
>> +		hw->notify_addr[i] = (void *)((u8 *)hw->notify_base +
>> +				     notify_off * hw->notify_off_multiplier);
>> +	}
>> +
>> +	hw->lm_cfg = hw->mem_resource[IFCVF_LM_BAR].addr;
>> +
>> +	IFC_DBG(&dev->dev, "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)
>> +{
>> +	u8 old_gen, new_gen, status;
>> +
>> +	do {
>> +		old_gen = ioread8(&hw->common_cfg->config_generation);
>> +		status = ioread8(&hw->common_cfg->device_status);
>> +		new_gen = ioread8(&hw->common_cfg->config_generation);
>> +	} while (old_gen != new_gen);
>> +
>> +	return status;
>> +}
>> +
>> +void ifcvf_set_status(struct ifcvf_hw *hw, u8 status)
>> +{
>> +	iowrite8(status, &hw->common_cfg->device_status);
>> +}
>> +
>> +void ifcvf_reset(struct ifcvf_hw *hw)
>> +{
>> +	ifcvf_set_status(hw, 0);
>> +	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 *cfg = hw->common_cfg;
>> +	u32 features_lo, features_hi;
>> +
>> +	iowrite32(0, &cfg->device_feature_select);
>> +	features_lo = ioread32(&cfg->device_feature);
>> +
>> +	iowrite32(1, &cfg->device_feature_select);
>> +	features_hi = 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 ifcvf_net_config));
>> +
>> +	do {
>> +		old_gen = ioread8(&hw->common_cfg->config_generation);
>> +		p = dst;
>> +
>> +		for (i = 0; i < length; i++)
>> +			*p++ = ioread8((u8 *)hw->net_cfg + offset + i);
>> +
>> +		new_gen = 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 ifcvf_net_config));
>> +
>> +	for (i = 0; i < length; i++)
>> +		iowrite8(*p++, (u8 *)hw->net_cfg + offset + i);
>> +}
>> +
>> +static void ifcvf_set_features(struct ifcvf_hw *hw, u64 features)
>> +{
>> +	struct virtio_pci_common_cfg *cfg = hw->common_cfg;
>> +
>> +	iowrite32(0, &cfg->guest_feature_select);
>> +	iowrite32(features & ((1ULL << 32) - 1), &cfg->guest_feature);
>> +
>> +	iowrite32(1, &cfg->guest_feature_select);
>> +	iowrite32(features >> 32, &cfg->guest_feature);
>> +}
>> +
>> +static int ifcvf_config_features(struct ifcvf_hw *hw)
>> +{
>> +	struct ifcvf_adapter *ifcvf;
>> +
>> +	ifcvf =	container_of(hw, struct ifcvf_adapter, vf);
>> +	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)) {
>> +		IFC_ERR(ifcvf->dev, "Failed to set FEATURES_OK status\n");
>> +		return -EIO;
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +void io_write64_twopart(u64 val, u32 *lo, u32 *hi)
>> +{
>> +	iowrite32(val & ((1ULL << 32) - 1), lo);
>> +	iowrite32(val >> 32, hi);
>> +}
>> +
>> +static int ifcvf_hw_enable(struct ifcvf_hw *hw)
>> +{
>> +	struct virtio_pci_common_cfg *cfg;
>> +	struct ifcvf_adapter *ifcvf;
>> +	u8 *lm_cfg;
>> +	u32 i;
>> +
>> +	ifcvf = container_of(hw, struct ifcvf_adapter, vf);
>> +	cfg = hw->common_cfg;
>> +	lm_cfg = hw->lm_cfg;
>> +	iowrite16(IFCVF_MSI_CONFIG_OFF, &cfg->msix_config);
>> +
>> +	if (ioread16(&cfg->msix_config) == VIRTIO_MSI_NO_VECTOR) {
>> +		IFC_ERR(ifcvf->dev, "No msix vector for device config.\n");
>> +		return -1;
>> +	}
>> +
>> +	for (i = 0; i < hw->nr_vring; i++) {
>> +		iowrite16(i, &cfg->queue_select);
>> +		io_write64_twopart(hw->vring[i].desc, &cfg->queue_desc_lo,
>> +				&cfg->queue_desc_hi);
>> +		io_write64_twopart(hw->vring[i].avail, &cfg->queue_avail_lo,
>> +				&cfg->queue_avail_hi);
>> +		io_write64_twopart(hw->vring[i].used, &cfg->queue_used_lo,
>> +				&cfg->queue_used_hi);
>> +		iowrite16(hw->vring[i].size, &cfg->queue_size);
>> +
>> +		*(u32 *)(lm_cfg + IFCVF_LM_RING_STATE_OFFSET +
>> +				(i / 2) * IFCVF_LM_CFG_SIZE + (i % 2) * 4) =
>> +			(u32)hw->vring[i].last_avail_idx |
>> +			((u32)hw->vring[i].last_used_idx << 16);
>> +
>> +		iowrite16(i + IFCVF_MSI_QUEUE_OFF, &cfg->queue_msix_vector);
>> +		if (ioread16(&cfg->queue_msix_vector) ==
>> +		    VIRTIO_MSI_NO_VECTOR) {
>> +			IFC_ERR(ifcvf->dev,
>> +				"No msix vector for queue %u.\n", i);
>> +			return -1;
>> +		}
>> +
>> +		iowrite16(1, &cfg->queue_enable);
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static void ifcvf_hw_disable(struct ifcvf_hw *hw)
>> +{
>> +	struct virtio_pci_common_cfg *cfg;
>> +	u32 i;
>> +
>> +	cfg = hw->common_cfg;
>> +	iowrite16(VIRTIO_MSI_NO_VECTOR, &cfg->msix_config);
>> +
>> +	for (i = 0; i < hw->nr_vring; i++) {
>> +		iowrite16(i, &cfg->queue_select);
>> +		iowrite16(0, &cfg->queue_enable);
>> +		iowrite16(VIRTIO_MSI_NO_VECTOR, &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 -1;
>> +
>> +	if (ifcvf_hw_enable(hw) < 0)
>> +		return -1;
>> +
>> +	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)
>> +{
>> +	iowrite16(qid, hw->notify_addr[qid]);
>> +}
>> +
>> +u64 ifcvf_get_queue_notify_off(struct ifcvf_hw *hw, int qid)
>> +{
>> +	return (u8 *)hw->notify_addr[qid] -
>> +		(u8 *)hw->mem_resource[hw->notify_bar].addr;
>> +}
>> diff --git a/drivers/vhost/ifcvf/ifcvf_base.h b/drivers/vhost/ifcvf/ifcvf_base.h
>> new file mode 100644
>> index 0000000..c97f0eb
>> --- /dev/null
>> +++ b/drivers/vhost/ifcvf/ifcvf_base.h
>> @@ -0,0 +1,132 @@
>> +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
>> +/*
>> + * Copyright (C) 2019 Intel Corporation.
>> + */
>> +
>> +#ifndef _IFCVF_H_
>> +#define _IFCVF_H_
>> +
>> +#include <linux/virtio_mdev_ops.h>
>> +#include <linux/mdev.h>
>> +#include <linux/pci.h>
>> +#include <linux/pci_regs.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_MDEV_LIMIT	1
>> +
>> +/*
>> + * Some ifcvf feature bits (currently bits 28 through 31) are
>> + * reserved for the transport being used (eg. ifcvf_ring), the
>> + * rest are per-device feature bits.
>> + */
>> +#define IFCVF_TRANSPORT_F_START 28
>> +#define IFCVF_TRANSPORT_F_END   34
>> +
>> +#define IFC_SUPPORTED_FEATURES \
>> +		((1ULL << VIRTIO_NET_F_MAC)			| \
>> +		 (1ULL << VIRTIO_F_ANY_LAYOUT)			| \
>> +		 (1ULL << VIRTIO_F_VERSION_1)			| \
>> +		 (1ULL << VIRTIO_F_ORDER_PLATFORM)			| \
> ACCESS_PLATFORM must be enabled for sure?

Hello Michael,

Thanks for your comment, I will add this bit, will send new patchset soon.

Thanks
Zhu Lingshan
>
>
>> +		 (1ULL << VIRTIO_NET_F_GUEST_ANNOUNCE)		| \
>> +		 (1ULL << VIRTIO_NET_F_CTRL_VQ)			| \
>> +		 (1ULL << VIRTIO_NET_F_STATUS)			| \
>> +		 (1ULL << VIRTIO_NET_F_MRG_RXBUF)) /* not fully supported */
>> +
>> +//Not support MQ, only one queue pair for now.
>> +#define IFCVF_MAX_QUEUE_PAIRS		1
>> +#define IFCVF_MAX_QUEUES		2
>> +
>> +#define IFCVF_QUEUE_ALIGNMENT		PAGE_SIZE
>> +
>> +#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_32_BIT_MASK		0xffffffff
>> +
>> +#define IFC_ERR(dev, fmt, ...)	dev_err(dev, fmt, ##__VA_ARGS__)
>> +#define IFC_DBG(dev, fmt, ...)	dev_dbg(dev, fmt, ##__VA_ARGS__)
>> +#define IFC_INFO(dev, fmt, ...)	dev_info(dev, fmt, ##__VA_ARGS__)
>> +
>> +#define IFC_PRIVATE_TO_VF(adapter) \
>> +	(&((struct ifcvf_adapter *)adapter)->vf)
>> +
>> +#define IFCVF_MAX_INTR (IFCVF_MAX_QUEUE_PAIRS * 2 + 1)
>> +
>> +struct ifcvf_net_config {
>> +	u8    mac[6];
>> +	u16   status;
>> +	u16   max_virtqueue_pairs;
>> +} __packed;
>> +
>> +struct ifcvf_pci_mem_resource {
>> +	/* Physical address, 0 if not resource. */
>> +	u64      phys_addr;
>> +	/* Length of the resource. */
>> +	u64      len;
>> +	/* Virtual address, NULL when not mapped. */
>> +	u8       *addr;
>> +};
>> +
>> +struct vring_info {
>> +	u64 desc;
>> +	u64 avail;
>> +	u64 used;
>> +	u16 size;
>> +	u16 last_avail_idx;
>> +	u16 last_used_idx;
>> +	bool ready;
>> +	char msix_name[256];
>> +	struct virtio_mdev_callback cb;
>> +};
>> +
>> +struct ifcvf_hw {
>> +	u8	*isr;
>> +	u8	notify_bar;
>> +	u8	*lm_cfg;
>> +	u8	nr_vring;
>> +	u16	*notify_base;
>> +	u16	*notify_addr[IFCVF_MAX_QUEUE_PAIRS * 2];
>> +	u32	notify_off_multiplier;
>> +	u64	req_features;
>> +	struct	virtio_pci_common_cfg *common_cfg;
>> +	struct	ifcvf_net_config *net_cfg;
>> +	struct	vring_info vring[IFCVF_MAX_QUEUE_PAIRS * 2];
>> +	struct	ifcvf_pci_mem_resource mem_resource[IFCVF_PCI_MAX_RESOURCE];
>> +};
>> +
>> +struct ifcvf_adapter {
>> +	struct	device *dev;
>> +	struct	mutex mdev_lock;
>> +	int	mdev_count;
>> +	int	vectors;
>> +	struct	ifcvf_hw vf;
>> +};
>> +
>> +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);
>> +u8 ifcvf_get_linkstatus(struct ifcvf_hw *hw);
>> +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);
>> +
>> +#endif /* _IFCVF_H_ */
>> -- 
>> 1.8.3.1

Re: [PATCH 1/2] IFC hardware operation layer

[Zhu Lingshan]

On 11/5/2019 7:29 PM, Michael S. Tsirkin wrote:
> On Tue, Nov 05, 2019 at 05:37:39PM +0800, Zhu Lingshan wrote:
>> This commit introduced ifcvf_base layer, which handles hardware
>> operations and configurations.
>>
>> Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
>> ---
>>   drivers/vhost/ifcvf/ifcvf_base.c | 344 +++++++++++++++++++++++++++++++++++++++
>>   drivers/vhost/ifcvf/ifcvf_base.h | 132 +++++++++++++++
>>   2 files changed, 476 insertions(+)
>>   create mode 100644 drivers/vhost/ifcvf/ifcvf_base.c
>>   create mode 100644 drivers/vhost/ifcvf/ifcvf_base.h
>>
>> diff --git a/drivers/vhost/ifcvf/ifcvf_base.c b/drivers/vhost/ifcvf/ifcvf_base.c
>> new file mode 100644
>> index 0000000..0659f41
>> --- /dev/null
>> +++ b/drivers/vhost/ifcvf/ifcvf_base.c
>> @@ -0,0 +1,344 @@
>> +// SPDX-License-Identifier: GPL-2.0-only
>> +/*
>> + * Copyright (C) 2019 Intel Corporation.
>> + */
>> +
>> +#include "ifcvf_base.h"
>> +
>> +static void *get_cap_addr(struct ifcvf_hw *hw, struct virtio_pci_cap *cap)
>> +{
>> +	struct ifcvf_adapter *ifcvf;
>> +	u32 length, offset;
>> +	u8 bar;
>> +
>> +	length = le32_to_cpu(cap->length);
>> +	offset = le32_to_cpu(cap->offset);
>> +	bar = le32_to_cpu(cap->bar);
>> +
>> +	ifcvf = container_of(hw, struct ifcvf_adapter, vf);
>> +
>> +	if (bar >= IFCVF_PCI_MAX_RESOURCE) {
>> +		IFC_DBG(ifcvf->dev,
>> +			"Invalid bar number %u to get capabilities.\n", bar);
>> +		return NULL;
>> +	}
>> +
>> +	if (offset + length < offset) {
>> +		IFC_DBG(ifcvf->dev, "offset(%u) + length(%u) overflows\n",
>> +			offset, length);
>> +		return NULL;
>> +	}
>> +
>> +	if (offset + length > hw->mem_resource[cap->bar].len) {
>> +		IFC_DBG(ifcvf->dev,
>> +			"offset(%u) + len(%u) overflows bar%u to get capabilities.\n",
>> +			offset, length, bar);
>> +		return NULL;
>> +	}
>> +
>> +	return hw->mem_resource[bar].addr + offset;
>> +}
>> +
>> +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 *dev)
>> +{
>> +	struct virtio_pci_cap cap;
>> +	u16 notify_off;
>> +	int ret;
>> +	u8 pos;
>> +	u32 i;
>> +
>> +	ret = pci_read_config_byte(dev, PCI_CAPABILITY_LIST, &pos);
>> +
>> +	if (ret < 0) {
>> +		IFC_ERR(&dev->dev, "Failed to read PCI capability list.\n");
>> +		return -EIO;
>> +	}
>> +
>> +	while (pos) {
>> +		ret = ifcvf_read_config_range(dev, (u32 *)&cap,
>> +					      sizeof(cap), pos);
>> +
>> +		if (ret < 0) {
>> +			IFC_ERR(&dev->dev, "Failed to get PCI capability at %x",
>> +				pos);
>> +			break;
>> +		}
>> +
>> +		if (cap.cap_vndr != PCI_CAP_ID_VNDR)
>> +			goto next;
>> +
>> +		IFC_DBG(&dev->dev, "read PCI config: config type: %u, PCI bar: %u,\
>> +			 PCI bar offset: %u, PCI config len: %u.\n",
>> +			cap.cfg_type, cap.bar, cap.offset, cap.length);
>> +
>> +		switch (cap.cfg_type) {
>> +		case VIRTIO_PCI_CAP_COMMON_CFG:
>> +			hw->common_cfg = get_cap_addr(hw, &cap);
>> +			IFC_INFO(&dev->dev, "hw->common_cfg = %p.\n",
>> +				 hw->common_cfg);
>> +			break;
>> +		case VIRTIO_PCI_CAP_NOTIFY_CFG:
>> +			pci_read_config_dword(dev, pos + sizeof(cap),
>> +					      &hw->notify_off_multiplier);
>> +			hw->notify_bar = cap.bar;
>> +			hw->notify_base = get_cap_addr(hw, &cap);
>> +			IFC_INFO(&dev->dev, "hw->notify_base = %p.\n",
>> +				 hw->notify_base);
>> +			break;
>> +		case VIRTIO_PCI_CAP_ISR_CFG:
>> +			hw->isr = get_cap_addr(hw, &cap);
>> +			IFC_INFO(&dev->dev, "hw->isr = %p.\n", hw->isr);
>> +			break;
>> +		case VIRTIO_PCI_CAP_DEVICE_CFG:
>> +			hw->net_cfg = get_cap_addr(hw, &cap);
>> +			IFC_INFO(&dev->dev, "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) {
>> +		IFC_DBG(&dev->dev, "Incomplete PCI capabilities.\n");
>> +		return -1;
>> +	}
>> +
>> +	for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++) {
>> +		iowrite16(i, &hw->common_cfg->queue_select);
>> +		notify_off = ioread16(&hw->common_cfg->queue_notify_off);
>> +		hw->notify_addr[i] = (void *)((u8 *)hw->notify_base +
>> +				     notify_off * hw->notify_off_multiplier);
>> +	}
>> +
>> +	hw->lm_cfg = hw->mem_resource[IFCVF_LM_BAR].addr;
>> +
>> +	IFC_DBG(&dev->dev, "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)
>> +{
>> +	u8 old_gen, new_gen, status;
>> +
>> +	do {
>> +		old_gen = ioread8(&hw->common_cfg->config_generation);
>> +		status = ioread8(&hw->common_cfg->device_status);
>> +		new_gen = ioread8(&hw->common_cfg->config_generation);
>> +	} while (old_gen != new_gen);
>> +
>> +	return status;
>> +}
>> +
>> +void ifcvf_set_status(struct ifcvf_hw *hw, u8 status)
>> +{
>> +	iowrite8(status, &hw->common_cfg->device_status);
>> +}
>> +
>> +void ifcvf_reset(struct ifcvf_hw *hw)
>> +{
>> +	ifcvf_set_status(hw, 0);
>> +	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 *cfg = hw->common_cfg;
>> +	u32 features_lo, features_hi;
>> +
>> +	iowrite32(0, &cfg->device_feature_select);
>> +	features_lo = ioread32(&cfg->device_feature);
>> +
>> +	iowrite32(1, &cfg->device_feature_select);
>> +	features_hi = 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 ifcvf_net_config));
>> +
>> +	do {
>> +		old_gen = ioread8(&hw->common_cfg->config_generation);
>> +		p = dst;
>> +
>> +		for (i = 0; i < length; i++)
>> +			*p++ = ioread8((u8 *)hw->net_cfg + offset + i);
>> +
>> +		new_gen = 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 ifcvf_net_config));
>> +
>> +	for (i = 0; i < length; i++)
>> +		iowrite8(*p++, (u8 *)hw->net_cfg + offset + i);
>> +}
>> +
>> +static void ifcvf_set_features(struct ifcvf_hw *hw, u64 features)
>> +{
>> +	struct virtio_pci_common_cfg *cfg = hw->common_cfg;
>> +
>> +	iowrite32(0, &cfg->guest_feature_select);
>> +	iowrite32(features & ((1ULL << 32) - 1), &cfg->guest_feature);
>> +
>> +	iowrite32(1, &cfg->guest_feature_select);
>> +	iowrite32(features >> 32, &cfg->guest_feature);
>> +}
>> +
>> +static int ifcvf_config_features(struct ifcvf_hw *hw)
>> +{
>> +	struct ifcvf_adapter *ifcvf;
>> +
>> +	ifcvf =	container_of(hw, struct ifcvf_adapter, vf);
>> +	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)) {
>> +		IFC_ERR(ifcvf->dev, "Failed to set FEATURES_OK status\n");
>> +		return -EIO;
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +void io_write64_twopart(u64 val, u32 *lo, u32 *hi)
>> +{
>> +	iowrite32(val & ((1ULL << 32) - 1), lo);
>> +	iowrite32(val >> 32, hi);
>> +}
>> +
>> +static int ifcvf_hw_enable(struct ifcvf_hw *hw)
>> +{
>> +	struct virtio_pci_common_cfg *cfg;
>> +	struct ifcvf_adapter *ifcvf;
>> +	u8 *lm_cfg;
>> +	u32 i;
>> +
>> +	ifcvf = container_of(hw, struct ifcvf_adapter, vf);
>> +	cfg = hw->common_cfg;
>> +	lm_cfg = hw->lm_cfg;
>> +	iowrite16(IFCVF_MSI_CONFIG_OFF, &cfg->msix_config);
>> +
>> +	if (ioread16(&cfg->msix_config) == VIRTIO_MSI_NO_VECTOR) {
>> +		IFC_ERR(ifcvf->dev, "No msix vector for device config.\n");
>> +		return -1;
>> +	}
>> +
>> +	for (i = 0; i < hw->nr_vring; i++) {
>> +		iowrite16(i, &cfg->queue_select);
>> +		io_write64_twopart(hw->vring[i].desc, &cfg->queue_desc_lo,
>> +				&cfg->queue_desc_hi);
>> +		io_write64_twopart(hw->vring[i].avail, &cfg->queue_avail_lo,
>> +				&cfg->queue_avail_hi);
>> +		io_write64_twopart(hw->vring[i].used, &cfg->queue_used_lo,
>> +				&cfg->queue_used_hi);
>> +		iowrite16(hw->vring[i].size, &cfg->queue_size);
>> +
>> +		*(u32 *)(lm_cfg + IFCVF_LM_RING_STATE_OFFSET +
>> +				(i / 2) * IFCVF_LM_CFG_SIZE + (i % 2) * 4) =
>> +			(u32)hw->vring[i].last_avail_idx |
>> +			((u32)hw->vring[i].last_used_idx << 16);
> Is this trying to store data into part of device memory BAR?
> If yes doing it like this isn't portable I think.
>
Hello Michael

Thanks for your comments, I will replace this with iowrite, I will use a 
variate representing the address to make it less-dirty.

>> +
>> +		iowrite16(i + IFCVF_MSI_QUEUE_OFF, &cfg->queue_msix_vector);
>> +		if (ioread16(&cfg->queue_msix_vector) ==
>> +		    VIRTIO_MSI_NO_VECTOR) {
>> +			IFC_ERR(ifcvf->dev,
>> +				"No msix vector for queue %u.\n", i);
>> +			return -1;
>> +		}
>> +
>> +		iowrite16(1, &cfg->queue_enable);
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static void ifcvf_hw_disable(struct ifcvf_hw *hw)
>> +{
>> +	struct virtio_pci_common_cfg *cfg;
>> +	u32 i;
>> +
>> +	cfg = hw->common_cfg;
>> +	iowrite16(VIRTIO_MSI_NO_VECTOR, &cfg->msix_config);
>> +
>> +	for (i = 0; i < hw->nr_vring; i++) {
>> +		iowrite16(i, &cfg->queue_select);
>> +		iowrite16(0, &cfg->queue_enable);
>> +		iowrite16(VIRTIO_MSI_NO_VECTOR, &cfg->queue_msix_vector);
>> +	}
> Is it enough to write like this? don't you need to read
> in order to flush outstanding MSI?
I will add a read here. Thanks
>
>
>> +}
>> +
>> +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 -1;
>> +
>> +	if (ifcvf_hw_enable(hw) < 0)
>> +		return -1;
>> +
>> +	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)
>> +{
>> +	iowrite16(qid, hw->notify_addr[qid]);
> I suspect you didn't validate this driver with sparse, did you?
> Otherwise I think you would have noticed some warnings
> as e.g. iowrite16 requires a __iomem address.
>
will add __iomem in the header files and other defines.
>> +}
>> +
>> +u64 ifcvf_get_queue_notify_off(struct ifcvf_hw *hw, int qid)
>> +{
>> +	return (u8 *)hw->notify_addr[qid] -
>> +		(u8 *)hw->mem_resource[hw->notify_bar].addr;
> why is the cast of addr need?
this function can be removed.
>
>> +}
>> diff --git a/drivers/vhost/ifcvf/ifcvf_base.h b/drivers/vhost/ifcvf/ifcvf_base.h
>> new file mode 100644
>> index 0000000..c97f0eb
>> --- /dev/null
>> +++ b/drivers/vhost/ifcvf/ifcvf_base.h
>> @@ -0,0 +1,132 @@
>> +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
>> +/*
>> + * Copyright (C) 2019 Intel Corporation.
>> + */
>> +
>> +#ifndef _IFCVF_H_
>> +#define _IFCVF_H_
>> +
>> +#include <linux/virtio_mdev_ops.h>
>> +#include <linux/mdev.h>
>> +#include <linux/pci.h>
>> +#include <linux/pci_regs.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
>
> I am confused by the above.
>
> They are used by the virtio layer right?
>
> So why isn't the id VIRTIO_ID_NET then?
without our driver, virtio-pci can drive this device, users can still 
use vfio passthrough on this device. We use VIRTIO_ID_NET in 
.get_device_id(), so virtio_mdev can match the device. 0x1041 only used 
in the id_table and the device reports 0x1041.
>
>> +#define IFCVF_SUBSYS_VENDOR_ID  0x8086
>> +#define IFCVF_SUBSYS_DEVICE_ID  0x001A
>> +
>> +#define IFCVF_MDEV_LIMIT	1
>> +
>> +/*
>> + * Some ifcvf feature bits (currently bits 28 through 31) are
>> + * reserved for the transport being used (eg. ifcvf_ring), the
>> + * rest are per-device feature bits.
>> + */
>> +#define IFCVF_TRANSPORT_F_START 28
>> +#define IFCVF_TRANSPORT_F_END   34
>> +
>> +#define IFC_SUPPORTED_FEATURES \
>> +		((1ULL << VIRTIO_NET_F_MAC)			| \
>> +		 (1ULL << VIRTIO_F_ANY_LAYOUT)			| \
>> +		 (1ULL << VIRTIO_F_VERSION_1)			| \
>> +		 (1ULL << VIRTIO_F_ORDER_PLATFORM)			| \
>> +		 (1ULL << VIRTIO_NET_F_GUEST_ANNOUNCE)		| \
>> +		 (1ULL << VIRTIO_NET_F_CTRL_VQ)			| \
>> +		 (1ULL << VIRTIO_NET_F_STATUS)			| \
>> +		 (1ULL << VIRTIO_NET_F_MRG_RXBUF)) /* not fully supported */
> what does this last one mean?
> shouldn't we clear the bit if it's incomplete?
it is supported now:)
>
>> +
>> +//Not support MQ, only one queue pair for now.
> /* comments like this pls */
sure
>
>> +#define IFCVF_MAX_QUEUE_PAIRS		1
>> +#define IFCVF_MAX_QUEUES		2
>> +
>> +#define IFCVF_QUEUE_ALIGNMENT		PAGE_SIZE
>> +
>> +#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_32_BIT_MASK		0xffffffff
>> +
>> +#define IFC_ERR(dev, fmt, ...)	dev_err(dev, fmt, ##__VA_ARGS__)
>> +#define IFC_DBG(dev, fmt, ...)	dev_dbg(dev, fmt, ##__VA_ARGS__)
>> +#define IFC_INFO(dev, fmt, ...)	dev_info(dev, fmt, ##__VA_ARGS__)
>> +
>> +#define IFC_PRIVATE_TO_VF(adapter) \
>> +	(&((struct ifcvf_adapter *)adapter)->vf)
>> +
>> +#define IFCVF_MAX_INTR (IFCVF_MAX_QUEUE_PAIRS * 2 + 1)
>> +
>> +struct ifcvf_net_config {
>> +	u8    mac[6];
>> +	u16   status;
>> +	u16   max_virtqueue_pairs;
>> +} __packed;
> Looks like a partial copy of virtio_net_config - reuse that one instead?
sure
>
>
>> +
>> +struct ifcvf_pci_mem_resource {
>> +	/* Physical address, 0 if not resource. */
>> +	u64      phys_addr;
>> +	/* Length of the resource. */
>> +	u64      len;
>> +	/* Virtual address, NULL when not mapped. */
>> +	u8       *addr;
>> +};
>> +
>> +struct vring_info {
>> +	u64 desc;
>> +	u64 avail;
>> +	u64 used;
>> +	u16 size;
>> +	u16 last_avail_idx;
>> +	u16 last_used_idx;
>> +	bool ready;
>> +	char msix_name[256];
>> +	struct virtio_mdev_callback cb;
>> +};
>> +
>> +struct ifcvf_hw {
>> +	u8	*isr;
>> +	u8	notify_bar;
>> +	u8	*lm_cfg;
>> +	u8	nr_vring;
>> +	u16	*notify_base;
>> +	u16	*notify_addr[IFCVF_MAX_QUEUE_PAIRS * 2];
>> +	u32	notify_off_multiplier;
>> +	u64	req_features;
>> +	struct	virtio_pci_common_cfg *common_cfg;
>> +	struct	ifcvf_net_config *net_cfg;
>> +	struct	vring_info vring[IFCVF_MAX_QUEUE_PAIRS * 2];
>> +	struct	ifcvf_pci_mem_resource mem_resource[IFCVF_PCI_MAX_RESOURCE];
>> +};
>> +
>> +struct ifcvf_adapter {
>> +	struct	device *dev;
>> +	struct	mutex mdev_lock;
>> +	int	mdev_count;
>> +	int	vectors;
>> +	struct	ifcvf_hw vf;
>> +};
>> +
>> +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);
>> +u8 ifcvf_get_linkstatus(struct ifcvf_hw *hw);
>> +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);
>> +
>> +#endif /* _IFCVF_H_ */
>> -- 
>> 1.8.3.1

Re: [PATCH 1/2] IFC hardware operation layer

[Zhu Lingshan]

On 11/6/2019 6:09 PM, Jason Wang wrote:
> On 2019/11/5 下午5:37, Zhu Lingshan wrote:
>> This commit introduced ifcvf_base layer, which handles hardware
>> operations and configurations.
> It looks like the PCI layout is pretty similar to virtio. Can we reuse
> e.g virtio_pci_modern_probe() (or helpers in virtio_pci_modern.c) to
> do the probing?

Hello Jason,

Thanks for your kindly comments. IMHO virtio_pci_modern_probe() probes 
the device after creating VFs, as we can see, virtio-pci can drive this 
device. To support virtio_mdev and vhost_mdev, we need to unbind the 
device from virtio-pci, then bind to this driver. In our driver probing, 
we did something quite different from virtio_pci_modern_porobe(), like 
memory resource mapping and other configs, yes we can reuse some helpers 
in virtio, but I wonder whether worth that.

>
>> Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
>> ---
>>   drivers/vhost/ifcvf/ifcvf_base.c | 344 +++++++++++++++++++++++++++++++++++++++
>>   drivers/vhost/ifcvf/ifcvf_base.h | 132 +++++++++++++++
>>   2 files changed, 476 insertions(+)
>>   create mode 100644 drivers/vhost/ifcvf/ifcvf_base.c
>>   create mode 100644 drivers/vhost/ifcvf/ifcvf_base.h
>>
>> diff --git a/drivers/vhost/ifcvf/ifcvf_base.c b/drivers/vhost/ifcvf/ifcvf_base.c
>> new file mode 100644
>> index 0000000..0659f41
>> --- /dev/null
>> +++ b/drivers/vhost/ifcvf/ifcvf_base.c
>> @@ -0,0 +1,344 @@
>> +// SPDX-License-Identifier: GPL-2.0-only
>> +/*
>> + * Copyright (C) 2019 Intel Corporation.
>> + */
>> +
>> +#include "ifcvf_base.h"
>> +
>> +static void *get_cap_addr(struct ifcvf_hw *hw, struct virtio_pci_cap *cap)
>> +{
>> +	struct ifcvf_adapter *ifcvf;
>> +	u32 length, offset;
>> +	u8 bar;
>> +
>> +	length = le32_to_cpu(cap->length);
>> +	offset = le32_to_cpu(cap->offset);
>> +	bar = le32_to_cpu(cap->bar);
>> +
>> +	ifcvf = container_of(hw, struct ifcvf_adapter, vf);
>> +
>> +	if (bar >= IFCVF_PCI_MAX_RESOURCE) {
>> +		IFC_DBG(ifcvf->dev,
>> +			"Invalid bar number %u to get capabilities.\n", bar);
>> +		return NULL;
>> +	}
>> +
>> +	if (offset + length < offset) {
> Can this really happen? Both offset and length are u32.
Thanks for point this out, removed.
>
>> +		IFC_DBG(ifcvf->dev, "offset(%u) + length(%u) overflows\n",
>> +			offset, length);
>> +		return NULL;
>> +	}
>> +
>> +	if (offset + length > hw->mem_resource[cap->bar].len) {
>> +		IFC_DBG(ifcvf->dev,
>> +			"offset(%u) + len(%u) overflows bar%u to get capabilities.\n",
>> +			offset, length, bar);
>> +		return NULL;
>> +	}
>> +
>> +	return hw->mem_resource[bar].addr + offset;
> I don't see the initialization of mem_resource in the patch, I wonder
> whether it's better to squash this patch just into patch 2.
I will split them into small patches in official versions. For RFC can I 
place this function here for now? init_hw also use it.
>
>> +}
>> +
>> +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 *dev)
>> +{
>> +	struct virtio_pci_cap cap;
>> +	u16 notify_off;
>> +	int ret;
>> +	u8 pos;
>> +	u32 i;
>> +
>> +	ret = pci_read_config_byte(dev, PCI_CAPABILITY_LIST, &pos);
>> +
>> +	if (ret < 0) {
>> +		IFC_ERR(&dev->dev, "Failed to read PCI capability list.\n");
>> +		return -EIO;
>> +	}
>> +
>> +	while (pos) {
>> +		ret = ifcvf_read_config_range(dev, (u32 *)&cap,
>> +					      sizeof(cap), pos);
>> +
>> +		if (ret < 0) {
>> +			IFC_ERR(&dev->dev, "Failed to get PCI capability at %x",
>> +				pos);
>> +			break;
>> +		}
>> +
>> +		if (cap.cap_vndr != PCI_CAP_ID_VNDR)
>> +			goto next;
>> +
>> +		IFC_DBG(&dev->dev, "read PCI config: config type: %u, PCI bar: %u,\
>> +			 PCI bar offset: %u, PCI config len: %u.\n",
>> +			cap.cfg_type, cap.bar, cap.offset, cap.length);
>> +
>> +		switch (cap.cfg_type) {
>> +		case VIRTIO_PCI_CAP_COMMON_CFG:
>> +			hw->common_cfg = get_cap_addr(hw, &cap);
>> +			IFC_INFO(&dev->dev, "hw->common_cfg = %p.\n",
>> +				 hw->common_cfg);
>> +			break;
>> +		case VIRTIO_PCI_CAP_NOTIFY_CFG:
>> +			pci_read_config_dword(dev, pos + sizeof(cap),
>> +					      &hw->notify_off_multiplier);
>> +			hw->notify_bar = cap.bar;
>> +			hw->notify_base = get_cap_addr(hw, &cap);
>> +			IFC_INFO(&dev->dev, "hw->notify_base = %p.\n",
>> +				 hw->notify_base);
>> +			break;
>> +		case VIRTIO_PCI_CAP_ISR_CFG:
>> +			hw->isr = get_cap_addr(hw, &cap);
>> +			IFC_INFO(&dev->dev, "hw->isr = %p.\n", hw->isr);
>> +			break;
>> +		case VIRTIO_PCI_CAP_DEVICE_CFG:
>> +			hw->net_cfg = get_cap_addr(hw, &cap);
>> +			IFC_INFO(&dev->dev, "hw->net_cfg = %p.\n", hw->net_cfg);
>> +			break;
> I think at least you can try to reuse e.g:
> virtio_pci_find_capability() to aovid duplicating codes.
Yes virtio_pci_find_capability() is nice, it will work perfect on a 
device. However users can create more than one hundred of VFs, 
virtio_pci_find_capability() will find all capabilities in O(n2), users 
may observe delays if we spend too much time finding the caps. It seems 
our O(n) code can save some time.
>
>> +		}
>> +next:
>> +		pos = cap.cap_next;
>> +	}
>> +
>> +	if (hw->common_cfg == NULL || hw->notify_base == NULL ||
>> +	    hw->isr == NULL || hw->net_cfg == NULL) {
>> +		IFC_DBG(&dev->dev, "Incomplete PCI capabilities.\n");
>> +		return -1;
> Maybe it's better to fail eailier.
>
>> +	}
>> +
>> +	for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++) {
>> +		iowrite16(i, &hw->common_cfg->queue_select);
>> +		notify_off = ioread16(&hw->common_cfg->queue_notify_off);
>> +		hw->notify_addr[i] = (void *)((u8 *)hw->notify_base +
>> +				     notify_off * hw->notify_off_multiplier);
> It might be better to store notify_addr inside the vring_info for
> better locality.
Agree, can do
>
>> +	}
>> +
>> +	hw->lm_cfg = hw->mem_resource[IFCVF_LM_BAR].addr;
>> +
>> +	IFC_DBG(&dev->dev, "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)
>> +{
>> +	u8 old_gen, new_gen, status;
>> +
>> +	do {
>> +		old_gen = ioread8(&hw->common_cfg->config_generation);
>> +		status = ioread8(&hw->common_cfg->device_status);
>> +		new_gen = ioread8(&hw->common_cfg->config_generation);
> config generation should be only used for config access not status,
> and even it did, it should be called from virtio core.
removed these code.
>
>> +	} while (old_gen != new_gen);
>> +
>> +	return status;
>> +}
>> +
>> +void ifcvf_set_status(struct ifcvf_hw *hw, u8 status)
>> +{
>> +	iowrite8(status, &hw->common_cfg->device_status);
>> +}
>> +
>> +void ifcvf_reset(struct ifcvf_hw *hw)
>> +{
>> +	ifcvf_set_status(hw, 0);
>> +	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 *cfg = hw->common_cfg;
>> +	u32 features_lo, features_hi;
>> +
>> +	iowrite32(0, &cfg->device_feature_select);
>> +	features_lo = ioread32(&cfg->device_feature);
>> +
>> +	iowrite32(1, &cfg->device_feature_select);
>> +	features_hi = 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 ifcvf_net_config));
>> +
>> +	do {
>> +		old_gen = ioread8(&hw->common_cfg->config_generation);
> Same here, virtio core has did the call for generation, so no need do
> do it again here.
removed
>
>> +		p = dst;
>> +
>> +		for (i = 0; i < length; i++)
>> +			*p++ = ioread8((u8 *)hw->net_cfg + offset + i);
>> +
>> +		new_gen = 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 ifcvf_net_config));
>> +
>> +	for (i = 0; i < length; i++)
>> +		iowrite8(*p++, (u8 *)hw->net_cfg + offset + i);
>> +}
>> +
>> +static void ifcvf_set_features(struct ifcvf_hw *hw, u64 features)
>> +{
>> +	struct virtio_pci_common_cfg *cfg = hw->common_cfg;
>> +
>> +	iowrite32(0, &cfg->guest_feature_select);
>> +	iowrite32(features & ((1ULL << 32) - 1), &cfg->guest_feature);
> (u32)features ?
Yes
>
>> +
>> +	iowrite32(1, &cfg->guest_feature_select);
>> +	iowrite32(features >> 32, &cfg->guest_feature);
>> +}
>> +
>> +static int ifcvf_config_features(struct ifcvf_hw *hw)
>> +{
>> +	struct ifcvf_adapter *ifcvf;
>> +
>> +	ifcvf =	container_of(hw, struct ifcvf_adapter, vf);
>> +	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)) {
>> +		IFC_ERR(ifcvf->dev, "Failed to set FEATURES_OK status\n");
>> +		return -EIO;
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +void io_write64_twopart(u64 val, u32 *lo, u32 *hi)
>> +{
>> +	iowrite32(val & ((1ULL << 32) - 1), lo);
>> +	iowrite32(val >> 32, hi);
>> +}
>> +
>> +static int ifcvf_hw_enable(struct ifcvf_hw *hw)
>> +{
>> +	struct virtio_pci_common_cfg *cfg;
>> +	struct ifcvf_adapter *ifcvf;
>> +	u8 *lm_cfg;
>> +	u32 i;
>> +
>> +	ifcvf = container_of(hw, struct ifcvf_adapter, vf);
>> +	cfg = hw->common_cfg;
>> +	lm_cfg = hw->lm_cfg;
>> +	iowrite16(IFCVF_MSI_CONFIG_OFF, &cfg->msix_config);
>> +
>> +	if (ioread16(&cfg->msix_config) == VIRTIO_MSI_NO_VECTOR) {
>> +		IFC_ERR(ifcvf->dev, "No msix vector for device config.\n");
>> +		return -1;
>> +	}
>> +
>> +	for (i = 0; i < hw->nr_vring; i++) {
>> +		iowrite16(i, &cfg->queue_select);
>> +		io_write64_twopart(hw->vring[i].desc, &cfg->queue_desc_lo,
>> +				&cfg->queue_desc_hi);
>> +		io_write64_twopart(hw->vring[i].avail, &cfg->queue_avail_lo,
>> +				&cfg->queue_avail_hi);
>> +		io_write64_twopart(hw->vring[i].used, &cfg->queue_used_lo,
>> +				&cfg->queue_used_hi);
>> +		iowrite16(hw->vring[i].size, &cfg->queue_size);
>> +
>> +		*(u32 *)(lm_cfg + IFCVF_LM_RING_STATE_OFFSET +
>> +				(i / 2) * IFCVF_LM_CFG_SIZE + (i % 2) * 4) =
>> +			(u32)hw->vring[i].last_avail_idx |
>> +			((u32)hw->vring[i].last_used_idx << 16);
> As pointed out by Michael, it's better to formalize lm_cfg as a
> structure instead of doing math here.
I can use a variable for the address, to make it better looking, also 
use iowrite() to make it portable.
>
>> +
>> +		iowrite16(i + IFCVF_MSI_QUEUE_OFF, &cfg->queue_msix_vector);
>> +		if (ioread16(&cfg->queue_msix_vector) ==
>> +		    VIRTIO_MSI_NO_VECTOR) {
>> +			IFC_ERR(ifcvf->dev,
>> +				"No msix vector for queue %u.\n", i);
>> +			return -1;
>> +		}
>> +
>> +		iowrite16(1, &cfg->queue_enable);
> This queue_enable should be done through set_vq_ready() from virtio core.
Agreed, but on our hardware, if we don't enable the queue, we can do 
nothing with the queue, even read something. so I have to leave it here.
But I changes set_vq_ready, now set_vq_ready() will sycn with hardware, 
we can use it to disable the queue as well.
>
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static void ifcvf_hw_disable(struct ifcvf_hw *hw)
>> +{
>> +	struct virtio_pci_common_cfg *cfg;
>> +	u32 i;
>> +
>> +	cfg = hw->common_cfg;
>> +	iowrite16(VIRTIO_MSI_NO_VECTOR, &cfg->msix_config);
>> +
>> +	for (i = 0; i < hw->nr_vring; i++) {
>> +		iowrite16(i, &cfg->queue_select);
>> +		iowrite16(0, &cfg->queue_enable);
>> +		iowrite16(VIRTIO_MSI_NO_VECTOR, &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 -1;
> It's better to set status to CONFIG_S_FAILED when fail.
Can do.
>
>> +
>> +	if (ifcvf_hw_enable(hw) < 0)
>> +		return -1;
>> +
>> +	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)
>> +{
>> +	iowrite16(qid, hw->notify_addr[qid]);
>> +}
>> +
>> +u64 ifcvf_get_queue_notify_off(struct ifcvf_hw *hw, int qid)
>> +{
>> +	return (u8 *)hw->notify_addr[qid] -
>> +		(u8 *)hw->mem_resource[hw->notify_bar].addr;
>> +}
>> diff --git a/drivers/vhost/ifcvf/ifcvf_base.h b/drivers/vhost/ifcvf/ifcvf_base.h
>> new file mode 100644
>> index 0000000..c97f0eb
>> --- /dev/null
>> +++ b/drivers/vhost/ifcvf/ifcvf_base.h
>> @@ -0,0 +1,132 @@
>> +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
>> +/*
>> + * Copyright (C) 2019 Intel Corporation.
>> + */
>> +
>> +#ifndef _IFCVF_H_
>> +#define _IFCVF_H_
>> +
>> +#include <linux/virtio_mdev_ops.h>
>> +#include <linux/mdev.h>
>> +#include <linux/pci.h>
>> +#include <linux/pci_regs.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_MDEV_LIMIT	1
>> +
>> +/*
>> + * Some ifcvf feature bits (currently bits 28 through 31) are
>> + * reserved for the transport being used (eg. ifcvf_ring), the
>> + * rest are per-device feature bits.
>> + */
>> +#define IFCVF_TRANSPORT_F_START 28
>> +#define IFCVF_TRANSPORT_F_END   34
>> +
>> +#define IFC_SUPPORTED_FEATURES \
>> +		((1ULL << VIRTIO_NET_F_MAC)			| \
>> +		 (1ULL << VIRTIO_F_ANY_LAYOUT)			| \
>> +		 (1ULL << VIRTIO_F_VERSION_1)			| \
>> +		 (1ULL << VIRTIO_F_ORDER_PLATFORM)			| \
>> +		 (1ULL << VIRTIO_NET_F_GUEST_ANNOUNCE)		| \
>> +		 (1ULL << VIRTIO_NET_F_CTRL_VQ)			| \
>> +		 (1ULL << VIRTIO_NET_F_STATUS)			| \
>> +		 (1ULL << VIRTIO_NET_F_MRG_RXBUF)) /* not fully supported */
> If it was not fully supported, we need to remove it.
It is supported now :)
>
>> +
>> +//Not support MQ, only one queue pair for now.
>> +#define IFCVF_MAX_QUEUE_PAIRS		1
>> +#define IFCVF_MAX_QUEUES		2
>> +
>> +#define IFCVF_QUEUE_ALIGNMENT		PAGE_SIZE
>> +
>> +#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_32_BIT_MASK		0xffffffff
>> +
>> +#define IFC_ERR(dev, fmt, ...)	dev_err(dev, fmt, ##__VA_ARGS__)
>> +#define IFC_DBG(dev, fmt, ...)	dev_dbg(dev, fmt, ##__VA_ARGS__)
>> +#define IFC_INFO(dev, fmt, ...)	dev_info(dev, fmt, ##__VA_ARGS__)
>> +
>> +#define IFC_PRIVATE_TO_VF(adapter) \
>> +	(&((struct ifcvf_adapter *)adapter)->vf)
>> +
>> +#define IFCVF_MAX_INTR (IFCVF_MAX_QUEUE_PAIRS * 2 + 1)
>> +
>> +struct ifcvf_net_config {
>> +	u8    mac[6];
>> +	u16   status;
>> +	u16   max_virtqueue_pairs;
>> +} __packed;
> Why not just use virtio_net_config?
Using virtio_net_config now.
>
>> +
>> +struct ifcvf_pci_mem_resource {
>> +	/* Physical address, 0 if not resource. */
>> +	u64      phys_addr;
>> +	/* Length of the resource. */
>> +	u64      len;
>> +	/* Virtual address, NULL when not mapped. */
>> +	u8       *addr;
>> +};
>> +
>> +struct vring_info {
>> +	u64 desc;
>> +	u64 avail;
>> +	u64 used;
>> +	u16 size;
>> +	u16 last_avail_idx;
>> +	u16 last_used_idx;
>> +	bool ready;
>> +	char msix_name[256];
>> +	struct virtio_mdev_callback cb;
>> +};
>> +
>> +struct ifcvf_hw {
>> +	u8	*isr;
>> +	u8	notify_bar;
>> +	u8	*lm_cfg;
>> +	u8	nr_vring;
>> +	u16	*notify_base;
>> +	u16	*notify_addr[IFCVF_MAX_QUEUE_PAIRS * 2];
>> +	u32	notify_off_multiplier;
>> +	u64	req_features;
>> +	struct	virtio_pci_common_cfg *common_cfg;
>> +	struct	ifcvf_net_config *net_cfg;
>> +	struct	vring_info vring[IFCVF_MAX_QUEUE_PAIRS * 2];
>> +	struct	ifcvf_pci_mem_resource mem_resource[IFCVF_PCI_MAX_RESOURCE];
>> +};
> It's better to add comments to explain each field.
Added comments for some obscure fields.
>
>> +
>> +struct ifcvf_adapter {
>> +	struct	device *dev;
>> +	struct	mutex mdev_lock;
>> +	int	mdev_count;
>> +	int	vectors;
>> +	struct	ifcvf_hw vf;
>> +};
>> +
>> +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);
>> +u8 ifcvf_get_linkstatus(struct ifcvf_hw *hw);
>> +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);
>> +
>> +#endif /* _IFCVF_H_ */
>> -- 
>> 1.8.3.1
>>

Re: [PATCH 2/2] IFC VDPA layer

[Zhu Lingshan]

On 11/6/2019 6:39 PM, Jason Wang wrote:
>
> ----- Original Message -----
>> This commit introduced IFC operations for vdpa, which complys to
>> virtio_mdev and vhost_mdev interfaces, handles IFC VF
>> initialization, configuration and removal.
>>
>> Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
>> ---
>>   drivers/vhost/ifcvf/ifcvf_main.c | 605
>>   +++++++++++++++++++++++++++++++++++++++
>>   1 file changed, 605 insertions(+)
>>   create mode 100644 drivers/vhost/ifcvf/ifcvf_main.c
>>
>> diff --git a/drivers/vhost/ifcvf/ifcvf_main.c
>> b/drivers/vhost/ifcvf/ifcvf_main.c
>> new file mode 100644
>> index 0000000..7165457
>> --- /dev/null
>> +++ b/drivers/vhost/ifcvf/ifcvf_main.c
>> @@ -0,0 +1,605 @@
>> +// SPDX-License-Identifier: GPL-2.0-only
>> +/*
>> + * Copyright (C) 2019 Intel Corporation.
>> + */
>> +
>> +#include <linux/interrupt.h>
>> +#include <linux/module.h>
>> +#include <linux/mdev.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 struct ifcvf_hw *mdev_to_vf(struct mdev_device *mdev)
>> +{
>> +	struct ifcvf_asapter *adapter = mdev_get_drvdata(mdev);
>> +	struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(adapter);
>> +
>> +	return vf;
>> +}
>> +
>> +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 u64 ifcvf_mdev_get_features(struct mdev_device *mdev)
>> +{
>> +	struct ifcvf_hw *vf = mdev_to_vf(mdev);
>> +
>> +	return ifcvf_get_features(vf);
>> +}
>> +
>> +static int ifcvf_mdev_set_features(struct mdev_device *mdev, u64 features)
>> +{
>> +	struct ifcvf_hw *vf = mdev_to_vf(mdev);
>> +
>> +	vf->req_features = features;
>> +
>> +	return 0;
>> +}
>> +
>> +static u64 ifcvf_mdev_get_vq_state(struct mdev_device *mdev, u16 qid)
>> +{
>> +	struct ifcvf_hw *vf = mdev_to_vf(mdev);
>> +	u16 last_avail_idx;
>> +
>> +	last_avail_idx = *(u16 *)(vf->lm_cfg + IFCVF_LM_RING_STATE_OFFSET +
>> +			 (qid / 2) * IFCVF_LM_CFG_SIZE + (qid % 2) * 4);
>> +
> Similar to the comment of previous patch, it's better to have a
> structure for lm_cfg.

Hello Jason,

Thanks for your comments!

Now I use an variable for the address, and iowrite() for portable purpose.

>> +	return last_avail_idx;
>> +}
>> +
>> +static int ifcvf_mdev_set_vq_state(struct mdev_device *mdev, u16 qid, u64
>> num)
>> +{
>> +	struct ifcvf_hw *vf = mdev_to_vf(mdev);
>> +
>> +	vf->vring[qid].last_avail_idx = num;
>> +
>> +	return 0;
>> +}
>> +
>> +static int ifcvf_mdev_set_vq_address(struct mdev_device *mdev, u16 idx,
>> +				     u64 desc_area, u64 driver_area,
>> +				     u64 device_area)
>> +{
>> +	struct ifcvf_hw *vf = mdev_to_vf(mdev);
>> +
>> +	vf->vring[idx].desc = desc_area;
>> +	vf->vring[idx].avail = driver_area;
>> +	vf->vring[idx].used = device_area;
>> +
>> +	return 0;
>> +}
>> +
>> +static void ifcvf_mdev_set_vq_num(struct mdev_device *mdev, u16 qid, u32
>> num)
>> +{
>> +	struct ifcvf_hw *vf = mdev_to_vf(mdev);
>> +
>> +	vf->vring[qid].size = num;
>> +}
>> +
>> +static void ifcvf_mdev_set_vq_ready(struct mdev_device *mdev,
>> +				    u16 qid, bool ready)
>> +{
>> +	struct ifcvf_hw *vf = mdev_to_vf(mdev);
>> +
>> +	vf->vring[qid].ready = ready;
> There should be a "iowrite16(1, &cfg->queue_enable)" here. And there's
> probably no need to store ready in vring in this case.
Yes
>
>> +}
>> +
>> +static bool ifcvf_mdev_get_vq_ready(struct mdev_device *mdev, u16 qid)
>> +{
>> +	struct ifcvf_hw *vf = mdev_to_vf(mdev);
>> +
>> +	return vf->vring[qid].ready;
> And the status should be read from cfg->queue_enable.
Yes
>
>> +}
>> +
>> +static void ifcvf_mdev_set_vq_cb(struct mdev_device *mdev, u16 idx,
>> +				 struct virtio_mdev_callback *cb)
>> +{
>> +	struct ifcvf_hw *vf = mdev_to_vf(mdev);
>> +
>> +	vf->vring[idx].cb = *cb;
>> +}
>> +
>> +static void ifcvf_mdev_kick_vq(struct mdev_device *mdev, u16 idx)
>> +{
>> +	struct ifcvf_hw *vf = mdev_to_vf(mdev);
>> +
>> +	ifcvf_notify_queue(vf, idx);
>> +}
>> +
>> +static u8 ifcvf_mdev_get_status(struct mdev_device *mdev)
>> +{
>> +	struct ifcvf_hw *vf = mdev_to_vf(mdev);
>> +
>> +	return ifcvf_get_status(vf);
>> +}
>> +
>> +static u32 ifcvf_mdev_get_generation(struct mdev_device *mdev)
>> +{
>> +	struct ifcvf_hw *vf = mdev_to_vf(mdev);
>> +
>> +	return ioread8(&vf->common_cfg->config_generation);
>> +}
>> +
>> +static u32 ifcvf_mdev_get_device_id(struct mdev_device *mdev)
>> +{
>> +	return VIRTIO_ID_NET;
>> +}
>> +
>> +static u32 ifcvf_mdev_get_vendor_id(struct mdev_device *mdev)
>> +{
>> +	return IFCVF_VENDOR_ID;
>> +}
>> +
>> +static u16 ifcvf_mdev_get_vq_align(struct mdev_device *mdev)
>> +{
>> +	return IFCVF_QUEUE_ALIGNMENT;
>> +}
>> +
>> +static u64 ifcvf_mdev_get_mdev_features(struct mdev_device *mdev)
>> +{
>> +	return VIRTIO_MDEV_F_VERSION_1;
>> +}
> We've decide to remove this API.
Removed.
>
>> +
>> +static int ifcvf_start_datapath(void *private)
>> +{
>> +	struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(private);
>> +	struct ifcvf_adapter *ifcvf;
>> +	int i, ret = 0;
>> +
>> +	ifcvf = container_of(vf, struct ifcvf_adapter, vf);
>> +
>> +	for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++) {
>> +		if (!vf->vring[i].ready) {
>> +			IFC_ERR(ifcvf->dev,
>> +				"Failed to start datapath, vring %d not ready.\n", i);
>> +			return -EINVAL;
>> +		}
> This should be not related. Driver can choose to not start a virtqueue.
removed the codes.
>
>> +
>> +		if (!vf->vring[i].size) {
>> +			IFC_ERR(ifcvf->dev,
>> +				"Failed to start datapath, vring %d size is zero.\n", i);
>> +			return -EINVAL;
>> +		}
>> +
>> +		if (!vf->vring[i].desc || !vf->vring[i].avail ||
>> +			!vf->vring[i].used) {
>> +			IFC_ERR(ifcvf->dev,
>> +				"Failed to start datapath, "
>> +				"invaild value for vring %d desc,"
>> +				"avail_idx or usex_idx.\n", i);
>> +			return -EINVAL;
>> +		}
>> +	}
>> +
>> +	vf->nr_vring = i;
>> +	ret = ifcvf_start_hw(vf);
> So basically there's no need for ifcvf_start_hw() to care about vq
> enablement, virtio core will take care of that through set_vq_ready().
Agreed, however if we don't enable the queue, I observe the hardware 
will not allow access to the queue, even reading something.
>
>> +
>> +	return ret;
>> +}
>> +
>> +static int ifcvf_stop_datapath(void *private)
>> +{
>> +	struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(private);
>> +	int i;
>> +
>> +	for (i = 0; i < IFCVF_MAX_QUEUES; 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 = IFC_PRIVATE_TO_VF(adapter);
>> +	struct virtio_pci_common_cfg *cfg;
>> +	u8 *lm_cfg;
>> +	int i;
>> +
>> +	cfg = vf->common_cfg;
>> +	lm_cfg = vf->lm_cfg;
>> +
>> +	for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++) {
>> +		vf->vring[i].last_used_idx = 0;
>> +		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->cb.callback = NULL;
>> +		vf->vring->cb.private = NULL;
>> +
>> +	}
>> +
>> +	ifcvf_reset(vf);
> So virtio-pci call vp_synchornize_vectors(), do need someting similar
> here (I mean in ifcvf_reset())?
Hardware handles most of the reset stuff, when reset the VF, we did not 
free irqs, the handler still working, so the on-flight irqs can be handled.
>
>> +}
>> +
>> +static void ifcvf_mdev_set_status(struct mdev_device *mdev, u8 status)
>> +{
>> +	struct ifcvf_adapter *adapter = mdev_get_drvdata(mdev);
>> +	struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(adapter);
>> +	int ret = 0;
>> +
>> +	if (status == 0) {
>> +		ifcvf_stop_datapath(adapter);
>> +		ifcvf_reset_vring(adapter);
>> +		return;
>> +	}
>> +
>> +	if (status & VIRTIO_CONFIG_S_DRIVER_OK) {
>> +		ret = ifcvf_start_datapath(adapter);
> If device support VIRTIO_CONFIG_S_DRIVER_OK, having something like
> start_datapath here looks wired.
>
> If it just to setup the virtqueue etc, can we simply move them to e.g
> set_vq_num, set_vq_address, etc?
IMHO, it does not just setup vqs, it also do some config and enabling 
works for the whole VF.
>
>> +
>> +		if (ret)
>> +			IFC_ERR(adapter->dev, "Failed to set mdev status %u.\n",
>> +				status);
>> +	}
>> +
>> +	ifcvf_set_status(vf, status);
>> +}
>> +
>> +static u16 ifcvf_mdev_get_vq_num_max(struct mdev_device *mdev)
>> +{
>> +	struct ifcvf_hw *vf = mdev_to_vf(mdev);
>> +
>> +	return vf->vring[0].size;
> It looks to me the only case that size is set is from
> ifcvf_mdev_set_vq_num()? So I don't get how is this supposed to
> work. I belive this should be a query for the hardware or a at least a
> macro?
Fixed.
>
>> +}
>> +static void ifcvf_mdev_get_config(struct mdev_device *mdev, unsigned int
>> offset,
>> +			     void *buf, unsigned int len)
>> +{
>> +	struct ifcvf_hw *vf = mdev_to_vf(mdev);
>> +
>> +	WARN_ON(offset + len > sizeof(struct ifcvf_net_config));
>> +	ifcvf_read_net_config(vf, offset, buf, len);
>> +}
>> +
>> +static void ifcvf_mdev_set_config(struct mdev_device *mdev, unsigned int
>> offset,
>> +			     const void *buf, unsigned int len)
>> +{
>> +	struct ifcvf_hw *vf = mdev_to_vf(mdev);
>> +
>> +	WARN_ON(offset + len > sizeof(struct ifcvf_net_config));
>> +	ifcvf_write_net_config(vf, offset, buf, len);
>> +}
>> +
>> +static struct virtio_mdev_device_ops ifc_mdev_ops = {
>> +	.get_features  = ifcvf_mdev_get_features,
>> +	.set_features  = ifcvf_mdev_set_features,
>> +	.get_status    = ifcvf_mdev_get_status,
>> +	.set_status    = ifcvf_mdev_set_status,
>> +	.get_vq_num_max = ifcvf_mdev_get_vq_num_max,
>> +	.get_vq_state   = ifcvf_mdev_get_vq_state,
>> +	.set_vq_state   = ifcvf_mdev_set_vq_state,
>> +	.set_vq_cb      = ifcvf_mdev_set_vq_cb,
>> +	.set_vq_ready   = ifcvf_mdev_set_vq_ready,
>> +	.get_vq_ready	= ifcvf_mdev_get_vq_ready,
>> +	.set_vq_num     = ifcvf_mdev_set_vq_num,
>> +	.set_vq_address = ifcvf_mdev_set_vq_address,
>> +	.kick_vq        = ifcvf_mdev_kick_vq,
>> +	.get_generation	= ifcvf_mdev_get_generation,
>> +	.get_device_id	= ifcvf_mdev_get_device_id,
>> +	.get_vendor_id	= ifcvf_mdev_get_vendor_id,
>> +	.get_vq_align	= ifcvf_mdev_get_vq_align,
>> +	.get_config	= ifcvf_mdev_get_config,
>> +	.set_config	= ifcvf_mdev_set_config,
>> +	.get_mdev_features = ifcvf_mdev_get_mdev_features,
> set_config_cb needs to be implemented since you claim to support VIRTIO_NET_F_STATUS.
control_vq feature bit is removed.
>
>> +};
>> +
>> +static int ifcvf_init_msix(struct ifcvf_adapter *adapter)
>> +{
>> +	struct pci_dev *pdev = to_pci_dev(adapter->dev);
>> +	struct ifcvf_hw *vf = &adapter->vf;
>> +	int vector, i, ret, irq;
>> +
>> +	ret = pci_alloc_irq_vectors(pdev, IFCVF_MAX_INTR,
>> +				    IFCVF_MAX_INTR, PCI_IRQ_MSIX);
>> +	if (ret < 0) {
>> +		IFC_ERR(adapter->dev, "Failed to alloc irq vectors.\n");
>> +		return ret;
>> +	}
>> +
>> +	for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++) {
>> +		vector = i + IFCVF_MSI_QUEUE_OFF;
>> +		irq = pci_irq_vector(pdev, vector);
>> +		ret = request_irq(irq, ifcvf_intr_handler, 0,
>> +				pci_name(pdev), &vf->vring[i]);
>> +		if (ret) {
>> +			IFC_ERR(adapter->dev,
>> +				"Failed to request irq for vq %d.\n", i);
>> +			return ret;
>> +		}
>> +	}
> Need allocate config interrupt here as well.
>
>> +
>> +	return 0;
>> +}
>> +
>> +static void ifcvf_destroy_adapter(struct ifcvf_adapter *adapter)
>> +{
>> +	struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(adapter);
>> +	struct pci_dev *pdev = to_pci_dev(adapter->dev);
>> +	int i, vector, irq;
>> +
>> +	for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++) {
>> +		vector = i + IFCVF_MSI_QUEUE_OFF;
>> +		irq = pci_irq_vector(pdev, vector);
>> +		free_irq(irq, &vf->vring[i]);
>> +	}
>> +}
>> +
>> +static ssize_t name_show(struct kobject *kobj, struct device *dev, char
>> *buf)
>> +{
>> +	const char *name = "vhost accelerator (virtio ring compatible)";
>> +
> I believe something like "IFCVF vhost/virtio accelerator" is better?
Agreed.
>
>> +	return sprintf(buf, "%s\n", name);
>> +}
>> +MDEV_TYPE_ATTR_RO(name);
>> +
>> +static ssize_t device_api_show(struct kobject *kobj, struct device *dev,
>> +			       char *buf)
>> +{
>> +	return sprintf(buf, "%s\n", VIRTIO_MDEV_DEVICE_API_STRING);
>> +}
>> +MDEV_TYPE_ATTR_RO(device_api);
>> +
>> +static ssize_t available_instances_show(struct kobject *kobj,
>> +					struct device *dev, char *buf)
>> +{
>> +	struct pci_dev *pdev;
>> +	struct ifcvf_adapter *adapter;
>> +
>> +	pdev = to_pci_dev(dev);
>> +	adapter = pci_get_drvdata(pdev);
>> +
>> +	return sprintf(buf, "%d\n", adapter->mdev_count);
>> +}
>> +
>> +MDEV_TYPE_ATTR_RO(available_instances);
>> +
>> +static ssize_t type_show(struct kobject *kobj,
>> +			struct device *dev, char *buf)
>> +{
>> +	return sprintf(buf, "%s\n", "net");
>> +}
>> +
>> +MDEV_TYPE_ATTR_RO(type);
>> +
>> +
>> +static struct attribute *mdev_types_attrs[] = {
>> +	&mdev_type_attr_name.attr,
>> +	&mdev_type_attr_device_api.attr,
>> +	&mdev_type_attr_available_instances.attr,
>> +	&mdev_type_attr_type.attr,
>> +	NULL,
>> +};
>> +
>> +static struct attribute_group mdev_type_group_virtio = {
>> +	.name  = "virtio_mdev",
>> +	.attrs = mdev_types_attrs,
>> +};
>> +
>> +static struct attribute_group mdev_type_group_vhost = {
>> +	.name  = "vhost_mdev",
>> +	.attrs = mdev_types_attrs,
>> +};
>> +
>> +static struct attribute_group *mdev_type_groups[] = {
>> +	&mdev_type_group_virtio,
>> +	&mdev_type_group_vhost,
>> +	NULL,
>> +};
>> +
>> +const struct attribute_group *mdev_dev_groups[] = {
>> +	NULL,
>> +};
>> +
>> +static int ifcvf_mdev_create(struct kobject *kobj, struct mdev_device *mdev)
>> +{
>> +	struct device *dev = mdev_parent_dev(mdev);
>> +	struct pci_dev *pdev = to_pci_dev(dev);
>> +	struct ifcvf_adapter *adapter = pci_get_drvdata(pdev);
>> +	int ret = 0;
>> +
>> +	mutex_lock(&adapter->mdev_lock);
>> +
>> +	if (adapter->mdev_count < IFCVF_MDEV_LIMIT) {
>> +		IFC_ERR(&pdev->dev,
>> +			"Can not create mdev, reached limitation %d.\n",
>> +			IFCVF_MDEV_LIMIT);
>> +		ret = -EINVAL;
>> +		goto out;
>> +	}
>> +
>> +	if (!strcmp(kobj->name, "ifcvf-virtio_mdev"))
>> +		mdev_set_virtio_ops(mdev, &ifc_mdev_ops);
>> +
>> +	if (!strcmp(kobj->name, "ifcvf-vhost_mdev"))
>> +		mdev_set_vhost_ops(mdev, &ifc_mdev_ops);
>> +
>> +	mdev_set_drvdata(mdev, adapter);
>> +	mdev_set_iommu_device(mdev_dev(mdev), dev);
>> +	adapter->mdev_count--;
>> +
>> +out:
>> +	mutex_unlock(&adapter->mdev_lock);
>> +	return ret;
>> +}
>> +
>> +static int ifcvf_mdev_remove(struct mdev_device *mdev)
>> +{
>> +	struct device *dev = mdev_parent_dev(mdev);
>> +	struct pci_dev *pdev = to_pci_dev(dev);
>> +	struct ifcvf_adapter *adapter = pci_get_drvdata(pdev);
>> +
>> +	mutex_lock(&adapter->mdev_lock);
>> +	adapter->mdev_count++;
>> +	mutex_unlock(&adapter->mdev_lock);
>> +
>> +	return 0;
>> +}
>> +
>> +static struct mdev_parent_ops ifcvf_mdev_fops = {
>> +	.owner			= THIS_MODULE,
>> +	.supported_type_groups	= mdev_type_groups,
>> +	.mdev_attr_groups	= mdev_dev_groups,
>> +	.create			= ifcvf_mdev_create,
>> +	.remove			= ifcvf_mdev_remove,
>> +};
>> +
>> +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, i;
>> +
>> +	adapter = kzalloc(sizeof(struct ifcvf_adapter), GFP_KERNEL);
>> +
>> +	if (adapter == NULL) {
>> +		ret = -ENOMEM;
>> +		goto fail;
>> +	}
>> +
>> +	mutex_init(&adapter->mdev_lock);
>> +	adapter->mdev_count = IFCVF_MDEV_LIMIT;
>> +	adapter->dev = dev;
>> +	pci_set_drvdata(pdev, adapter);
>> +	ret = pci_enable_device(pdev);
>> +
>> +	if (ret) {
>> +		IFC_ERR(adapter->dev, "Failed to enable device.\n");
>> +		goto free_adapter;
>> +	}
>> +
>> +	ret = pci_request_regions(pdev, IFCVF_DRIVER_NAME);
>> +
>> +	if (ret) {
>> +		IFC_ERR(adapter->dev, "Failed to request MMIO region.\n");
>> +		goto disable_device;
>> +	}
>> +
>> +	pci_set_master(pdev);
>> +	ret = ifcvf_init_msix(adapter);
>> +
>> +	if (ret) {
>> +		IFC_ERR(adapter->dev, "Failed to initialize MSIX.\n");
>> +		goto free_msix;
>> +	}
>> +
>> +	vf = &adapter->vf;
>> +
>> +	for (i = 0; i < IFCVF_PCI_MAX_RESOURCE; i++) {
>> +		vf->mem_resource[i].phys_addr = pci_resource_start(pdev, i);
>> +		vf->mem_resource[i].len = pci_resource_len(pdev, i);
>> +		if (!vf->mem_resource[i].len) {
>> +			vf->mem_resource[i].addr = NULL;
>> +			continue;
>> +		}
>> +
>> +		vf->mem_resource[i].addr = pci_iomap_range(pdev, i, 0,
>> +				vf->mem_resource[i].len);
>> +		if (!vf->mem_resource[i].addr) {
>> +			IFC_ERR(adapter->dev, "Failed to map IO resource %d\n",
>> +				i);
>> +			ret = -1;
>> +			goto free_msix;
>> +		}
>> +	}
>> +
>> +	if (ifcvf_init_hw(vf, pdev) < 0) {
>> +		ret = -1;
>> +		goto destroy_adapter;
>> +	}
>> +
>> +	ret = mdev_register_device(dev, &ifcvf_mdev_fops);
>> +
>> +	if (ret) {
>> +		IFC_ERR(adapter->dev,  "Failed to register mdev device\n");
>> +		goto destroy_adapter;
>> +	}
>> +
>> +	return 0;
>> +
>> +destroy_adapter:
>> +	ifcvf_destroy_adapter(adapter);
>> +free_msix:
>> +	pci_free_irq_vectors(pdev);
>> +	pci_release_regions(pdev);
>> +disable_device:
>> +	pci_disable_device(pdev);
>> +free_adapter:
>> +	kfree(adapter);
>> +fail:
>> +	return ret;
>> +}
>> +
>> +static void ifcvf_remove(struct pci_dev *pdev)
>> +{
>> +	struct ifcvf_adapter *adapter = pci_get_drvdata(pdev);
>> +	struct device *dev = &pdev->dev;
>> +	struct ifcvf_hw *vf;
>> +	int i;
>> +
>> +	mdev_unregister_device(dev);
>> +
>> +	vf = &adapter->vf;
>> +	for (i = 0; i < IFCVF_PCI_MAX_RESOURCE; i++) {
>> +		if (vf->mem_resource[i].addr) {
>> +			pci_iounmap(pdev, vf->mem_resource[i].addr);
>> +			vf->mem_resource[i].addr = NULL;
>> +		}
>> +	}
>> +
>> +	ifcvf_destroy_adapter(adapter);
>> +	pci_free_irq_vectors(pdev);
>> +	pci_release_regions(pdev);
>> +	pci_disable_device(pdev);
>> +	kfree(adapter);
>> +}
>> +
>> +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,
>> +};
>> +
>> +static int __init ifcvf_init_module(void)
>> +{
>> +	int ret;
>> +
>> +	ret = pci_register_driver(&ifcvf_driver);
>> +	return ret;
>> +}
>> +
>> +static void __exit ifcvf_exit_module(void)
>> +{
>> +	pci_unregister_driver(&ifcvf_driver);
>> +}
> You probably can do something simpler thorugh module_pci_driver().
>
> Thanks
>
>> +
>> +module_init(ifcvf_init_module);
>> +module_exit(ifcvf_exit_module);
>> +
>> +MODULE_LICENSE("GPL v2");
>> +MODULE_VERSION(VERSION_STRING);
>> +MODULE_AUTHOR(DRIVER_AUTHOR);
>> --
>> 1.8.3.1
>>
>>

Re: [PATCH 1/2] IFC hardware operation layer

[Michael S. Tsirkin]

On Tue, Nov 05, 2019 at 05:37:39PM +0800, Zhu Lingshan wrote:
> This commit introduced ifcvf_base layer, which handles hardware
> operations and configurations.
> 
> Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
> ---
>  drivers/vhost/ifcvf/ifcvf_base.c | 344 +++++++++++++++++++++++++++++++++++++++
>  drivers/vhost/ifcvf/ifcvf_base.h | 132 +++++++++++++++
>  2 files changed, 476 insertions(+)
>  create mode 100644 drivers/vhost/ifcvf/ifcvf_base.c
>  create mode 100644 drivers/vhost/ifcvf/ifcvf_base.h
> 
> diff --git a/drivers/vhost/ifcvf/ifcvf_base.c b/drivers/vhost/ifcvf/ifcvf_base.c
> new file mode 100644
> index 0000000..0659f41
> --- /dev/null
> +++ b/drivers/vhost/ifcvf/ifcvf_base.c
> @@ -0,0 +1,344 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Copyright (C) 2019 Intel Corporation.
> + */
> +
> +#include "ifcvf_base.h"
> +
> +static void *get_cap_addr(struct ifcvf_hw *hw, struct virtio_pci_cap *cap)
> +{
> +	struct ifcvf_adapter *ifcvf;
> +	u32 length, offset;
> +	u8 bar;
> +
> +	length = le32_to_cpu(cap->length);
> +	offset = le32_to_cpu(cap->offset);
> +	bar = le32_to_cpu(cap->bar);
> +
> +	ifcvf = container_of(hw, struct ifcvf_adapter, vf);
> +
> +	if (bar >= IFCVF_PCI_MAX_RESOURCE) {
> +		IFC_DBG(ifcvf->dev,
> +			"Invalid bar number %u to get capabilities.\n", bar);
> +		return NULL;
> +	}
> +
> +	if (offset + length < offset) {
> +		IFC_DBG(ifcvf->dev, "offset(%u) + length(%u) overflows\n",
> +			offset, length);
> +		return NULL;
> +	}
> +
> +	if (offset + length > hw->mem_resource[cap->bar].len) {
> +		IFC_DBG(ifcvf->dev,
> +			"offset(%u) + len(%u) overflows bar%u to get capabilities.\n",
> +			offset, length, bar);
> +		return NULL;
> +	}
> +
> +	return hw->mem_resource[bar].addr + offset;
> +}
> +
> +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 *dev)
> +{
> +	struct virtio_pci_cap cap;
> +	u16 notify_off;
> +	int ret;
> +	u8 pos;
> +	u32 i;
> +
> +	ret = pci_read_config_byte(dev, PCI_CAPABILITY_LIST, &pos);
> +
> +	if (ret < 0) {
> +		IFC_ERR(&dev->dev, "Failed to read PCI capability list.\n");
> +		return -EIO;
> +	}
> +
> +	while (pos) {
> +		ret = ifcvf_read_config_range(dev, (u32 *)&cap,
> +					      sizeof(cap), pos);
> +
> +		if (ret < 0) {
> +			IFC_ERR(&dev->dev, "Failed to get PCI capability at %x",
> +				pos);
> +			break;
> +		}
> +
> +		if (cap.cap_vndr != PCI_CAP_ID_VNDR)
> +			goto next;
> +
> +		IFC_DBG(&dev->dev, "read PCI config: config type: %u, PCI bar: %u,\
> +			 PCI bar offset: %u, PCI config len: %u.\n",
> +			cap.cfg_type, cap.bar, cap.offset, cap.length);
> +
> +		switch (cap.cfg_type) {
> +		case VIRTIO_PCI_CAP_COMMON_CFG:
> +			hw->common_cfg = get_cap_addr(hw, &cap);
> +			IFC_INFO(&dev->dev, "hw->common_cfg = %p.\n",
> +				 hw->common_cfg);
> +			break;
> +		case VIRTIO_PCI_CAP_NOTIFY_CFG:
> +			pci_read_config_dword(dev, pos + sizeof(cap),
> +					      &hw->notify_off_multiplier);
> +			hw->notify_bar = cap.bar;
> +			hw->notify_base = get_cap_addr(hw, &cap);
> +			IFC_INFO(&dev->dev, "hw->notify_base = %p.\n",
> +				 hw->notify_base);
> +			break;
> +		case VIRTIO_PCI_CAP_ISR_CFG:
> +			hw->isr = get_cap_addr(hw, &cap);
> +			IFC_INFO(&dev->dev, "hw->isr = %p.\n", hw->isr);
> +			break;
> +		case VIRTIO_PCI_CAP_DEVICE_CFG:
> +			hw->net_cfg = get_cap_addr(hw, &cap);
> +			IFC_INFO(&dev->dev, "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) {
> +		IFC_DBG(&dev->dev, "Incomplete PCI capabilities.\n");
> +		return -1;
> +	}
> +
> +	for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++) {
> +		iowrite16(i, &hw->common_cfg->queue_select);
> +		notify_off = ioread16(&hw->common_cfg->queue_notify_off);
> +		hw->notify_addr[i] = (void *)((u8 *)hw->notify_base +
> +				     notify_off * hw->notify_off_multiplier);
> +	}
> +
> +	hw->lm_cfg = hw->mem_resource[IFCVF_LM_BAR].addr;
> +
> +	IFC_DBG(&dev->dev, "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)
> +{
> +	u8 old_gen, new_gen, status;
> +
> +	do {
> +		old_gen = ioread8(&hw->common_cfg->config_generation);
> +		status = ioread8(&hw->common_cfg->device_status);
> +		new_gen = ioread8(&hw->common_cfg->config_generation);
> +	} while (old_gen != new_gen);
> +
> +	return status;
> +}
> +
> +void ifcvf_set_status(struct ifcvf_hw *hw, u8 status)
> +{
> +	iowrite8(status, &hw->common_cfg->device_status);
> +}
> +
> +void ifcvf_reset(struct ifcvf_hw *hw)
> +{
> +	ifcvf_set_status(hw, 0);
> +	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 *cfg = hw->common_cfg;
> +	u32 features_lo, features_hi;
> +
> +	iowrite32(0, &cfg->device_feature_select);
> +	features_lo = ioread32(&cfg->device_feature);
> +
> +	iowrite32(1, &cfg->device_feature_select);
> +	features_hi = 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 ifcvf_net_config));
> +
> +	do {
> +		old_gen = ioread8(&hw->common_cfg->config_generation);
> +		p = dst;
> +
> +		for (i = 0; i < length; i++)
> +			*p++ = ioread8((u8 *)hw->net_cfg + offset + i);
> +
> +		new_gen = 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 ifcvf_net_config));
> +
> +	for (i = 0; i < length; i++)
> +		iowrite8(*p++, (u8 *)hw->net_cfg + offset + i);
> +}
> +
> +static void ifcvf_set_features(struct ifcvf_hw *hw, u64 features)
> +{
> +	struct virtio_pci_common_cfg *cfg = hw->common_cfg;
> +
> +	iowrite32(0, &cfg->guest_feature_select);
> +	iowrite32(features & ((1ULL << 32) - 1), &cfg->guest_feature);
> +
> +	iowrite32(1, &cfg->guest_feature_select);
> +	iowrite32(features >> 32, &cfg->guest_feature);
> +}
> +
> +static int ifcvf_config_features(struct ifcvf_hw *hw)
> +{
> +	struct ifcvf_adapter *ifcvf;
> +
> +	ifcvf =	container_of(hw, struct ifcvf_adapter, vf);
> +	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)) {
> +		IFC_ERR(ifcvf->dev, "Failed to set FEATURES_OK status\n");
> +		return -EIO;
> +	}
> +
> +	return 0;
> +}
> +
> +void io_write64_twopart(u64 val, u32 *lo, u32 *hi)
> +{
> +	iowrite32(val & ((1ULL << 32) - 1), lo);
> +	iowrite32(val >> 32, hi);
> +}
> +
> +static int ifcvf_hw_enable(struct ifcvf_hw *hw)
> +{
> +	struct virtio_pci_common_cfg *cfg;
> +	struct ifcvf_adapter *ifcvf;
> +	u8 *lm_cfg;
> +	u32 i;
> +
> +	ifcvf = container_of(hw, struct ifcvf_adapter, vf);
> +	cfg = hw->common_cfg;
> +	lm_cfg = hw->lm_cfg;
> +	iowrite16(IFCVF_MSI_CONFIG_OFF, &cfg->msix_config);
> +
> +	if (ioread16(&cfg->msix_config) == VIRTIO_MSI_NO_VECTOR) {
> +		IFC_ERR(ifcvf->dev, "No msix vector for device config.\n");
> +		return -1;
> +	}
> +
> +	for (i = 0; i < hw->nr_vring; i++) {
> +		iowrite16(i, &cfg->queue_select);
> +		io_write64_twopart(hw->vring[i].desc, &cfg->queue_desc_lo,
> +				&cfg->queue_desc_hi);
> +		io_write64_twopart(hw->vring[i].avail, &cfg->queue_avail_lo,
> +				&cfg->queue_avail_hi);
> +		io_write64_twopart(hw->vring[i].used, &cfg->queue_used_lo,
> +				&cfg->queue_used_hi);
> +		iowrite16(hw->vring[i].size, &cfg->queue_size);
> +
> +		*(u32 *)(lm_cfg + IFCVF_LM_RING_STATE_OFFSET +
> +				(i / 2) * IFCVF_LM_CFG_SIZE + (i % 2) * 4) =
> +			(u32)hw->vring[i].last_avail_idx |
> +			((u32)hw->vring[i].last_used_idx << 16);
> +
> +		iowrite16(i + IFCVF_MSI_QUEUE_OFF, &cfg->queue_msix_vector);
> +		if (ioread16(&cfg->queue_msix_vector) ==
> +		    VIRTIO_MSI_NO_VECTOR) {
> +			IFC_ERR(ifcvf->dev,
> +				"No msix vector for queue %u.\n", i);
> +			return -1;
> +		}
> +
> +		iowrite16(1, &cfg->queue_enable);
> +	}
> +
> +	return 0;
> +}
> +
> +static void ifcvf_hw_disable(struct ifcvf_hw *hw)
> +{
> +	struct virtio_pci_common_cfg *cfg;
> +	u32 i;
> +
> +	cfg = hw->common_cfg;
> +	iowrite16(VIRTIO_MSI_NO_VECTOR, &cfg->msix_config);
> +
> +	for (i = 0; i < hw->nr_vring; i++) {
> +		iowrite16(i, &cfg->queue_select);
> +		iowrite16(0, &cfg->queue_enable);
> +		iowrite16(VIRTIO_MSI_NO_VECTOR, &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 -1;
> +
> +	if (ifcvf_hw_enable(hw) < 0)
> +		return -1;
> +
> +	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)
> +{
> +	iowrite16(qid, hw->notify_addr[qid]);
> +}
> +
> +u64 ifcvf_get_queue_notify_off(struct ifcvf_hw *hw, int qid)
> +{
> +	return (u8 *)hw->notify_addr[qid] -
> +		(u8 *)hw->mem_resource[hw->notify_bar].addr;
> +}
> diff --git a/drivers/vhost/ifcvf/ifcvf_base.h b/drivers/vhost/ifcvf/ifcvf_base.h
> new file mode 100644
> index 0000000..c97f0eb
> --- /dev/null
> +++ b/drivers/vhost/ifcvf/ifcvf_base.h
> @@ -0,0 +1,132 @@
> +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
> +/*
> + * Copyright (C) 2019 Intel Corporation.

Given this borrowed BSD licensed code from virtio, can you make this
licensed similarly?
See e.g. include/uapi/linux/virtio_config.h for the license to use.


> + */
> +
> +#ifndef _IFCVF_H_
> +#define _IFCVF_H_
> +
> +#include <linux/virtio_mdev_ops.h>
> +#include <linux/mdev.h>
> +#include <linux/pci.h>
> +#include <linux/pci_regs.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_MDEV_LIMIT	1
> +
> +/*
> + * Some ifcvf feature bits (currently bits 28 through 31) are
> + * reserved for the transport being used (eg. ifcvf_ring), the
> + * rest are per-device feature bits.
> + */
> +#define IFCVF_TRANSPORT_F_START 28
> +#define IFCVF_TRANSPORT_F_END   34
> +
> +#define IFC_SUPPORTED_FEATURES \
> +		((1ULL << VIRTIO_NET_F_MAC)			| \
> +		 (1ULL << VIRTIO_F_ANY_LAYOUT)			| \
> +		 (1ULL << VIRTIO_F_VERSION_1)			| \
> +		 (1ULL << VIRTIO_F_ORDER_PLATFORM)			| \
> +		 (1ULL << VIRTIO_NET_F_GUEST_ANNOUNCE)		| \
> +		 (1ULL << VIRTIO_NET_F_CTRL_VQ)			| \
> +		 (1ULL << VIRTIO_NET_F_STATUS)			| \
> +		 (1ULL << VIRTIO_NET_F_MRG_RXBUF)) /* not fully supported */
> +
> +//Not support MQ, only one queue pair for now.
> +#define IFCVF_MAX_QUEUE_PAIRS		1
> +#define IFCVF_MAX_QUEUES		2
> +
> +#define IFCVF_QUEUE_ALIGNMENT		PAGE_SIZE
> +
> +#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_32_BIT_MASK		0xffffffff
> +
> +#define IFC_ERR(dev, fmt, ...)	dev_err(dev, fmt, ##__VA_ARGS__)
> +#define IFC_DBG(dev, fmt, ...)	dev_dbg(dev, fmt, ##__VA_ARGS__)
> +#define IFC_INFO(dev, fmt, ...)	dev_info(dev, fmt, ##__VA_ARGS__)
> +
> +#define IFC_PRIVATE_TO_VF(adapter) \
> +	(&((struct ifcvf_adapter *)adapter)->vf)
> +
> +#define IFCVF_MAX_INTR (IFCVF_MAX_QUEUE_PAIRS * 2 + 1)
> +
> +struct ifcvf_net_config {
> +	u8    mac[6];
> +	u16   status;
> +	u16   max_virtqueue_pairs;
> +} __packed;
> +
> +struct ifcvf_pci_mem_resource {
> +	/* Physical address, 0 if not resource. */
> +	u64      phys_addr;
> +	/* Length of the resource. */
> +	u64      len;
> +	/* Virtual address, NULL when not mapped. */
> +	u8       *addr;
> +};
> +
> +struct vring_info {
> +	u64 desc;
> +	u64 avail;
> +	u64 used;
> +	u16 size;
> +	u16 last_avail_idx;
> +	u16 last_used_idx;
> +	bool ready;
> +	char msix_name[256];
> +	struct virtio_mdev_callback cb;
> +};
> +
> +struct ifcvf_hw {
> +	u8	*isr;
> +	u8	notify_bar;
> +	u8	*lm_cfg;
> +	u8	nr_vring;
> +	u16	*notify_base;
> +	u16	*notify_addr[IFCVF_MAX_QUEUE_PAIRS * 2];
> +	u32	notify_off_multiplier;
> +	u64	req_features;
> +	struct	virtio_pci_common_cfg *common_cfg;
> +	struct	ifcvf_net_config *net_cfg;
> +	struct	vring_info vring[IFCVF_MAX_QUEUE_PAIRS * 2];
> +	struct	ifcvf_pci_mem_resource mem_resource[IFCVF_PCI_MAX_RESOURCE];
> +};
> +
> +struct ifcvf_adapter {
> +	struct	device *dev;
> +	struct	mutex mdev_lock;
> +	int	mdev_count;
> +	int	vectors;
> +	struct	ifcvf_hw vf;
> +};
> +
> +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);
> +u8 ifcvf_get_linkstatus(struct ifcvf_hw *hw);
> +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);
> +
> +#endif /* _IFCVF_H_ */
> -- 
> 1.8.3.1

Re: [PATCH 1/2] IFC hardware operation layer

[Zhu Lingshan]

On 11/8/2019 8:57 PM, Michael S. Tsirkin wrote:
> On Tue, Nov 05, 2019 at 05:37:39PM +0800, Zhu Lingshan wrote:
>> This commit introduced ifcvf_base layer, which handles hardware
>> operations and configurations.
>>
>> Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
>> ---
>>   drivers/vhost/ifcvf/ifcvf_base.c | 344 +++++++++++++++++++++++++++++++++++++++
>>   drivers/vhost/ifcvf/ifcvf_base.h | 132 +++++++++++++++
>>   2 files changed, 476 insertions(+)
>>   create mode 100644 drivers/vhost/ifcvf/ifcvf_base.c
>>   create mode 100644 drivers/vhost/ifcvf/ifcvf_base.h
>>
>> diff --git a/drivers/vhost/ifcvf/ifcvf_base.c b/drivers/vhost/ifcvf/ifcvf_base.c
>> new file mode 100644
>> index 0000000..0659f41
>> --- /dev/null
>> +++ b/drivers/vhost/ifcvf/ifcvf_base.c
>> @@ -0,0 +1,344 @@
>> +// SPDX-License-Identifier: GPL-2.0-only
>> +/*
>> + * Copyright (C) 2019 Intel Corporation.
>> + */
>> +
>> +#include "ifcvf_base.h"
>> +
>> +static void *get_cap_addr(struct ifcvf_hw *hw, struct virtio_pci_cap *cap)
>> +{
>> +	struct ifcvf_adapter *ifcvf;
>> +	u32 length, offset;
>> +	u8 bar;
>> +
>> +	length = le32_to_cpu(cap->length);
>> +	offset = le32_to_cpu(cap->offset);
>> +	bar = le32_to_cpu(cap->bar);
>> +
>> +	ifcvf = container_of(hw, struct ifcvf_adapter, vf);
>> +
>> +	if (bar >= IFCVF_PCI_MAX_RESOURCE) {
>> +		IFC_DBG(ifcvf->dev,
>> +			"Invalid bar number %u to get capabilities.\n", bar);
>> +		return NULL;
>> +	}
>> +
>> +	if (offset + length < offset) {
>> +		IFC_DBG(ifcvf->dev, "offset(%u) + length(%u) overflows\n",
>> +			offset, length);
>> +		return NULL;
>> +	}
>> +
>> +	if (offset + length > hw->mem_resource[cap->bar].len) {
>> +		IFC_DBG(ifcvf->dev,
>> +			"offset(%u) + len(%u) overflows bar%u to get capabilities.\n",
>> +			offset, length, bar);
>> +		return NULL;
>> +	}
>> +
>> +	return hw->mem_resource[bar].addr + offset;
>> +}
>> +
>> +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 *dev)
>> +{
>> +	struct virtio_pci_cap cap;
>> +	u16 notify_off;
>> +	int ret;
>> +	u8 pos;
>> +	u32 i;
>> +
>> +	ret = pci_read_config_byte(dev, PCI_CAPABILITY_LIST, &pos);
>> +
>> +	if (ret < 0) {
>> +		IFC_ERR(&dev->dev, "Failed to read PCI capability list.\n");
>> +		return -EIO;
>> +	}
>> +
>> +	while (pos) {
>> +		ret = ifcvf_read_config_range(dev, (u32 *)&cap,
>> +					      sizeof(cap), pos);
>> +
>> +		if (ret < 0) {
>> +			IFC_ERR(&dev->dev, "Failed to get PCI capability at %x",
>> +				pos);
>> +			break;
>> +		}
>> +
>> +		if (cap.cap_vndr != PCI_CAP_ID_VNDR)
>> +			goto next;
>> +
>> +		IFC_DBG(&dev->dev, "read PCI config: config type: %u, PCI bar: %u,\
>> +			 PCI bar offset: %u, PCI config len: %u.\n",
>> +			cap.cfg_type, cap.bar, cap.offset, cap.length);
>> +
>> +		switch (cap.cfg_type) {
>> +		case VIRTIO_PCI_CAP_COMMON_CFG:
>> +			hw->common_cfg = get_cap_addr(hw, &cap);
>> +			IFC_INFO(&dev->dev, "hw->common_cfg = %p.\n",
>> +				 hw->common_cfg);
>> +			break;
>> +		case VIRTIO_PCI_CAP_NOTIFY_CFG:
>> +			pci_read_config_dword(dev, pos + sizeof(cap),
>> +					      &hw->notify_off_multiplier);
>> +			hw->notify_bar = cap.bar;
>> +			hw->notify_base = get_cap_addr(hw, &cap);
>> +			IFC_INFO(&dev->dev, "hw->notify_base = %p.\n",
>> +				 hw->notify_base);
>> +			break;
>> +		case VIRTIO_PCI_CAP_ISR_CFG:
>> +			hw->isr = get_cap_addr(hw, &cap);
>> +			IFC_INFO(&dev->dev, "hw->isr = %p.\n", hw->isr);
>> +			break;
>> +		case VIRTIO_PCI_CAP_DEVICE_CFG:
>> +			hw->net_cfg = get_cap_addr(hw, &cap);
>> +			IFC_INFO(&dev->dev, "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) {
>> +		IFC_DBG(&dev->dev, "Incomplete PCI capabilities.\n");
>> +		return -1;
>> +	}
>> +
>> +	for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++) {
>> +		iowrite16(i, &hw->common_cfg->queue_select);
>> +		notify_off = ioread16(&hw->common_cfg->queue_notify_off);
>> +		hw->notify_addr[i] = (void *)((u8 *)hw->notify_base +
>> +				     notify_off * hw->notify_off_multiplier);
>> +	}
>> +
>> +	hw->lm_cfg = hw->mem_resource[IFCVF_LM_BAR].addr;
>> +
>> +	IFC_DBG(&dev->dev, "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)
>> +{
>> +	u8 old_gen, new_gen, status;
>> +
>> +	do {
>> +		old_gen = ioread8(&hw->common_cfg->config_generation);
>> +		status = ioread8(&hw->common_cfg->device_status);
>> +		new_gen = ioread8(&hw->common_cfg->config_generation);
>> +	} while (old_gen != new_gen);
>> +
>> +	return status;
>> +}
>> +
>> +void ifcvf_set_status(struct ifcvf_hw *hw, u8 status)
>> +{
>> +	iowrite8(status, &hw->common_cfg->device_status);
>> +}
>> +
>> +void ifcvf_reset(struct ifcvf_hw *hw)
>> +{
>> +	ifcvf_set_status(hw, 0);
>> +	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 *cfg = hw->common_cfg;
>> +	u32 features_lo, features_hi;
>> +
>> +	iowrite32(0, &cfg->device_feature_select);
>> +	features_lo = ioread32(&cfg->device_feature);
>> +
>> +	iowrite32(1, &cfg->device_feature_select);
>> +	features_hi = 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 ifcvf_net_config));
>> +
>> +	do {
>> +		old_gen = ioread8(&hw->common_cfg->config_generation);
>> +		p = dst;
>> +
>> +		for (i = 0; i < length; i++)
>> +			*p++ = ioread8((u8 *)hw->net_cfg + offset + i);
>> +
>> +		new_gen = 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 ifcvf_net_config));
>> +
>> +	for (i = 0; i < length; i++)
>> +		iowrite8(*p++, (u8 *)hw->net_cfg + offset + i);
>> +}
>> +
>> +static void ifcvf_set_features(struct ifcvf_hw *hw, u64 features)
>> +{
>> +	struct virtio_pci_common_cfg *cfg = hw->common_cfg;
>> +
>> +	iowrite32(0, &cfg->guest_feature_select);
>> +	iowrite32(features & ((1ULL << 32) - 1), &cfg->guest_feature);
>> +
>> +	iowrite32(1, &cfg->guest_feature_select);
>> +	iowrite32(features >> 32, &cfg->guest_feature);
>> +}
>> +
>> +static int ifcvf_config_features(struct ifcvf_hw *hw)
>> +{
>> +	struct ifcvf_adapter *ifcvf;
>> +
>> +	ifcvf =	container_of(hw, struct ifcvf_adapter, vf);
>> +	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)) {
>> +		IFC_ERR(ifcvf->dev, "Failed to set FEATURES_OK status\n");
>> +		return -EIO;
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +void io_write64_twopart(u64 val, u32 *lo, u32 *hi)
>> +{
>> +	iowrite32(val & ((1ULL << 32) - 1), lo);
>> +	iowrite32(val >> 32, hi);
>> +}
>> +
>> +static int ifcvf_hw_enable(struct ifcvf_hw *hw)
>> +{
>> +	struct virtio_pci_common_cfg *cfg;
>> +	struct ifcvf_adapter *ifcvf;
>> +	u8 *lm_cfg;
>> +	u32 i;
>> +
>> +	ifcvf = container_of(hw, struct ifcvf_adapter, vf);
>> +	cfg = hw->common_cfg;
>> +	lm_cfg = hw->lm_cfg;
>> +	iowrite16(IFCVF_MSI_CONFIG_OFF, &cfg->msix_config);
>> +
>> +	if (ioread16(&cfg->msix_config) == VIRTIO_MSI_NO_VECTOR) {
>> +		IFC_ERR(ifcvf->dev, "No msix vector for device config.\n");
>> +		return -1;
>> +	}
>> +
>> +	for (i = 0; i < hw->nr_vring; i++) {
>> +		iowrite16(i, &cfg->queue_select);
>> +		io_write64_twopart(hw->vring[i].desc, &cfg->queue_desc_lo,
>> +				&cfg->queue_desc_hi);
>> +		io_write64_twopart(hw->vring[i].avail, &cfg->queue_avail_lo,
>> +				&cfg->queue_avail_hi);
>> +		io_write64_twopart(hw->vring[i].used, &cfg->queue_used_lo,
>> +				&cfg->queue_used_hi);
>> +		iowrite16(hw->vring[i].size, &cfg->queue_size);
>> +
>> +		*(u32 *)(lm_cfg + IFCVF_LM_RING_STATE_OFFSET +
>> +				(i / 2) * IFCVF_LM_CFG_SIZE + (i % 2) * 4) =
>> +			(u32)hw->vring[i].last_avail_idx |
>> +			((u32)hw->vring[i].last_used_idx << 16);
>> +
>> +		iowrite16(i + IFCVF_MSI_QUEUE_OFF, &cfg->queue_msix_vector);
>> +		if (ioread16(&cfg->queue_msix_vector) ==
>> +		    VIRTIO_MSI_NO_VECTOR) {
>> +			IFC_ERR(ifcvf->dev,
>> +				"No msix vector for queue %u.\n", i);
>> +			return -1;
>> +		}
>> +
>> +		iowrite16(1, &cfg->queue_enable);
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static void ifcvf_hw_disable(struct ifcvf_hw *hw)
>> +{
>> +	struct virtio_pci_common_cfg *cfg;
>> +	u32 i;
>> +
>> +	cfg = hw->common_cfg;
>> +	iowrite16(VIRTIO_MSI_NO_VECTOR, &cfg->msix_config);
>> +
>> +	for (i = 0; i < hw->nr_vring; i++) {
>> +		iowrite16(i, &cfg->queue_select);
>> +		iowrite16(0, &cfg->queue_enable);
>> +		iowrite16(VIRTIO_MSI_NO_VECTOR, &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 -1;
>> +
>> +	if (ifcvf_hw_enable(hw) < 0)
>> +		return -1;
>> +
>> +	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)
>> +{
>> +	iowrite16(qid, hw->notify_addr[qid]);
>> +}
>> +
>> +u64 ifcvf_get_queue_notify_off(struct ifcvf_hw *hw, int qid)
>> +{
>> +	return (u8 *)hw->notify_addr[qid] -
>> +		(u8 *)hw->mem_resource[hw->notify_bar].addr;
>> +}
>> diff --git a/drivers/vhost/ifcvf/ifcvf_base.h b/drivers/vhost/ifcvf/ifcvf_base.h
>> new file mode 100644
>> index 0000000..c97f0eb
>> --- /dev/null
>> +++ b/drivers/vhost/ifcvf/ifcvf_base.h
>> @@ -0,0 +1,132 @@
>> +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
>> +/*
>> + * Copyright (C) 2019 Intel Corporation.
> Given this borrowed BSD licensed code from virtio, can you make this
> licensed similarly?
> See e.g. include/uapi/linux/virtio_config.h for the license to use.
>
We can discuss this issue, will send RFC V3 next Monday

THanks!

>> + */
>> +
>> +#ifndef _IFCVF_H_
>> +#define _IFCVF_H_
>> +
>> +#include <linux/virtio_mdev_ops.h>
>> +#include <linux/mdev.h>
>> +#include <linux/pci.h>
>> +#include <linux/pci_regs.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_MDEV_LIMIT	1
>> +
>> +/*
>> + * Some ifcvf feature bits (currently bits 28 through 31) are
>> + * reserved for the transport being used (eg. ifcvf_ring), the
>> + * rest are per-device feature bits.
>> + */
>> +#define IFCVF_TRANSPORT_F_START 28
>> +#define IFCVF_TRANSPORT_F_END   34
>> +
>> +#define IFC_SUPPORTED_FEATURES \
>> +		((1ULL << VIRTIO_NET_F_MAC)			| \
>> +		 (1ULL << VIRTIO_F_ANY_LAYOUT)			| \
>> +		 (1ULL << VIRTIO_F_VERSION_1)			| \
>> +		 (1ULL << VIRTIO_F_ORDER_PLATFORM)			| \
>> +		 (1ULL << VIRTIO_NET_F_GUEST_ANNOUNCE)		| \
>> +		 (1ULL << VIRTIO_NET_F_CTRL_VQ)			| \
>> +		 (1ULL << VIRTIO_NET_F_STATUS)			| \
>> +		 (1ULL << VIRTIO_NET_F_MRG_RXBUF)) /* not fully supported */
>> +
>> +//Not support MQ, only one queue pair for now.
>> +#define IFCVF_MAX_QUEUE_PAIRS		1
>> +#define IFCVF_MAX_QUEUES		2
>> +
>> +#define IFCVF_QUEUE_ALIGNMENT		PAGE_SIZE
>> +
>> +#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_32_BIT_MASK		0xffffffff
>> +
>> +#define IFC_ERR(dev, fmt, ...)	dev_err(dev, fmt, ##__VA_ARGS__)
>> +#define IFC_DBG(dev, fmt, ...)	dev_dbg(dev, fmt, ##__VA_ARGS__)
>> +#define IFC_INFO(dev, fmt, ...)	dev_info(dev, fmt, ##__VA_ARGS__)
>> +
>> +#define IFC_PRIVATE_TO_VF(adapter) \
>> +	(&((struct ifcvf_adapter *)adapter)->vf)
>> +
>> +#define IFCVF_MAX_INTR (IFCVF_MAX_QUEUE_PAIRS * 2 + 1)
>> +
>> +struct ifcvf_net_config {
>> +	u8    mac[6];
>> +	u16   status;
>> +	u16   max_virtqueue_pairs;
>> +} __packed;
>> +
>> +struct ifcvf_pci_mem_resource {
>> +	/* Physical address, 0 if not resource. */
>> +	u64      phys_addr;
>> +	/* Length of the resource. */
>> +	u64      len;
>> +	/* Virtual address, NULL when not mapped. */
>> +	u8       *addr;
>> +};
>> +
>> +struct vring_info {
>> +	u64 desc;
>> +	u64 avail;
>> +	u64 used;
>> +	u16 size;
>> +	u16 last_avail_idx;
>> +	u16 last_used_idx;
>> +	bool ready;
>> +	char msix_name[256];
>> +	struct virtio_mdev_callback cb;
>> +};
>> +
>> +struct ifcvf_hw {
>> +	u8	*isr;
>> +	u8	notify_bar;
>> +	u8	*lm_cfg;
>> +	u8	nr_vring;
>> +	u16	*notify_base;
>> +	u16	*notify_addr[IFCVF_MAX_QUEUE_PAIRS * 2];
>> +	u32	notify_off_multiplier;
>> +	u64	req_features;
>> +	struct	virtio_pci_common_cfg *common_cfg;
>> +	struct	ifcvf_net_config *net_cfg;
>> +	struct	vring_info vring[IFCVF_MAX_QUEUE_PAIRS * 2];
>> +	struct	ifcvf_pci_mem_resource mem_resource[IFCVF_PCI_MAX_RESOURCE];
>> +};
>> +
>> +struct ifcvf_adapter {
>> +	struct	device *dev;
>> +	struct	mutex mdev_lock;
>> +	int	mdev_count;
>> +	int	vectors;
>> +	struct	ifcvf_hw vf;
>> +};
>> +
>> +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);
>> +u8 ifcvf_get_linkstatus(struct ifcvf_hw *hw);
>> +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);
>> +
>> +#endif /* _IFCVF_H_ */
>> -- 
>> 1.8.3.1

Re: [PATCH 2/2] IFC VDPA layer

[Mark D Rustad]

[-- Attachment #1: Type: text/plain, Size: 1834 bytes --]

On Nov 5, 2019, at 1:37 AM, Zhu Lingshan <lingshan.zhu@intel.com> wrote:

> This commit introduced IFC operations for vdpa, which complys to
> virtio_mdev and vhost_mdev interfaces, handles IFC VF
> initialization, configuration and removal.
>
> Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
> ---
>  drivers/vhost/ifcvf/ifcvf_main.c | 605 +++++++++++++++++++++++++++++++++++++++
>  1 file changed, 605 insertions(+)
>  create mode 100644 drivers/vhost/ifcvf/ifcvf_main.c
>
> diff --git a/drivers/vhost/ifcvf/ifcvf_main.c  
> b/drivers/vhost/ifcvf/ifcvf_main.c
> new file mode 100644
> index 0000000..7165457
> --- /dev/null
> +++ b/drivers/vhost/ifcvf/ifcvf_main.c
> @@ -0,0 +1,605 @@

<snip>

> +	for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++) {
> +		if (!vf->vring[i].ready) {
> +			IFC_ERR(ifcvf->dev,
> +				"Failed to start datapath, vring %d not ready.\n", i);
> +			return -EINVAL;
> +		}
> +
> +		if (!vf->vring[i].size) {
> +			IFC_ERR(ifcvf->dev,
> +				"Failed to start datapath, vring %d size is zero.\n", i);
> +			return -EINVAL;
> +		}
> +
> +		if (!vf->vring[i].desc || !vf->vring[i].avail ||
> +			!vf->vring[i].used) {
> +			IFC_ERR(ifcvf->dev,
> +				"Failed to start datapath, "
> +				"invaild value for vring %d desc,"
> +				"avail_idx or usex_idx.\n", i);

Please don't break up the format string. Start it on the second line and  
let it run as long as it needs to. Also you will find that it is improperly  
spaced as it is. It makes it easier to grep the source to find the source  
of a message. The coding style has an explicit exception for such long  
lines for this reason.

Also, please don't put .'s on the end of log messages. It serves no purpose  
and just adds to the log, the binary size and the source size. There are  
quite a few of these.

<snip>

--
Mark Rustad, MRustad@gmail.com

[-- Attachment #2: Message signed with OpenPGP --]
[-- Type: application/pgp-signature, Size: 873 bytes --]

Re: [PATCH 1/2] IFC hardware operation layer

[Mark D Rustad]

[-- Attachment #1: Type: text/plain, Size: 3806 bytes --]

On Tue, Nov 05, 2019 at 05:37:39PM +0800, Zhu Lingshan wrote:
> This commit introduced ifcvf_base layer, which handles hardware
> operations and configurations.
>
> Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
> ---
>  drivers/vhost/ifcvf/ifcvf_base.c | 344 +++++++++++++++++++++++++++++++++++++++
>  drivers/vhost/ifcvf/ifcvf_base.h | 132 +++++++++++++++
>  2 files changed, 476 insertions(+)
>  create mode 100644 drivers/vhost/ifcvf/ifcvf_base.c
>  create mode 100644 drivers/vhost/ifcvf/ifcvf_base.h
>
> diff --git a/drivers/vhost/ifcvf/ifcvf_base.c  
> b/drivers/vhost/ifcvf/ifcvf_base.c
> new file mode 100644
> index 0000000..0659f41
> --- /dev/null
> +++ b/drivers/vhost/ifcvf/ifcvf_base.c
> @@ -0,0 +1,344 @@

<snip>

> +	while (pos) {
> +		ret = ifcvf_read_config_range(dev, (u32 *)&cap,
> +					      sizeof(cap), pos);
> +
> +		if (ret < 0) {
> +			IFC_ERR(&dev->dev, "Failed to get PCI capability at %x",

Missing a \n on the message.

> +				pos);
> +			break;
> +		}
> +
> +		if (cap.cap_vndr != PCI_CAP_ID_VNDR)
> +			goto next;
> +
> +		IFC_DBG(&dev->dev, "read PCI config: config type: %u, PCI bar: %u,\
> +			 PCI bar offset: %u, PCI config len: %u.\n",

Really do not continue strings in this way. Again, just start the format on  
the second line and let it be as long as it needs to be. Also drop the . on  
the end of the log messages (there are many in this patch).

> +			cap.cfg_type, cap.bar, cap.offset, cap.length);
>
<snip>

> +	hw->lm_cfg = hw->mem_resource[IFCVF_LM_BAR].addr;
> +
> +	IFC_DBG(&dev->dev, "PCI capability mapping: common cfg: %p,\
> +		notify base: %p\n, isr cfg: %p, device cfg: %p,\
> +		multiplier: %u\n",

Another continued long format string to go onto one line.

> +		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)
> +{
> +	u8 old_gen, new_gen, status;
> +
> +	do {
> +		old_gen = ioread8(&hw->common_cfg->config_generation);
> +		status = ioread8(&hw->common_cfg->device_status);
> +		new_gen = ioread8(&hw->common_cfg->config_generation);
> +	} while (old_gen != new_gen);
> +
> +	return status;
> +}
> +
> +void ifcvf_set_status(struct ifcvf_hw *hw, u8 status)
> +{
> +	iowrite8(status, &hw->common_cfg->device_status);
> +}
> +
> +void ifcvf_reset(struct ifcvf_hw *hw)
> +{
> +	ifcvf_set_status(hw, 0);
> +	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 *cfg = hw->common_cfg;
> +	u32 features_lo, features_hi;
> +
> +	iowrite32(0, &cfg->device_feature_select);
> +	features_lo = ioread32(&cfg->device_feature);
> +
> +	iowrite32(1, &cfg->device_feature_select);
> +	features_hi = 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 ifcvf_net_config));
> +
> +	do {
> +		old_gen = ioread8(&hw->common_cfg->config_generation);
> +		p = dst;
> +
> +		for (i = 0; i < length; i++)
> +			*p++ = ioread8((u8 *)hw->net_cfg + offset + i);
> +
> +		new_gen = 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 ifcvf_net_config));

No space after sizeof.

<snip>

--
Mark Rustad, MRustad@gmail.com

[-- Attachment #2: Message signed with OpenPGP --]
[-- Type: application/pgp-signature, Size: 873 bytes --]

Re: [PATCH 2/2] IFC VDPA layer

[Zhu Lingshan]

Hello Mark,

Thanks for your comments, I will change the lines in next patchset.

Thanks,
BR
Zhu Lingshan
On 11/10/2019 3:56 AM, Mark D Rustad wrote:
> On Nov 5, 2019, at 1:37 AM, Zhu Lingshan <lingshan.zhu@intel.com> wrote:
>
>> This commit introduced IFC operations for vdpa, which complys to
>> virtio_mdev and vhost_mdev interfaces, handles IFC VF
>> initialization, configuration and removal.
>>
>> Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
>> ---
>>  drivers/vhost/ifcvf/ifcvf_main.c | 605 
>> +++++++++++++++++++++++++++++++++++++++
>>  1 file changed, 605 insertions(+)
>>  create mode 100644 drivers/vhost/ifcvf/ifcvf_main.c
>>
>> diff --git a/drivers/vhost/ifcvf/ifcvf_main.c 
>> b/drivers/vhost/ifcvf/ifcvf_main.c
>> new file mode 100644
>> index 0000000..7165457
>> --- /dev/null
>> +++ b/drivers/vhost/ifcvf/ifcvf_main.c
>> @@ -0,0 +1,605 @@
>
> <snip>
>
>> +    for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++) {
>> +        if (!vf->vring[i].ready) {
>> +            IFC_ERR(ifcvf->dev,
>> +                "Failed to start datapath, vring %d not ready.\n", i);
>> +            return -EINVAL;
>> +        }
>> +
>> +        if (!vf->vring[i].size) {
>> +            IFC_ERR(ifcvf->dev,
>> +                "Failed to start datapath, vring %d size is 
>> zero.\n", i);
>> +            return -EINVAL;
>> +        }
>> +
>> +        if (!vf->vring[i].desc || !vf->vring[i].avail ||
>> +            !vf->vring[i].used) {
>> +            IFC_ERR(ifcvf->dev,
>> +                "Failed to start datapath, "
>> +                "invaild value for vring %d desc,"
>> +                "avail_idx or usex_idx.\n", i);
>
> Please don't break up the format string. Start it on the second line 
> and let it run as long as it needs to. Also you will find that it is 
> improperly spaced as it is. It makes it easier to grep the source to 
> find the source of a message. The coding style has an explicit 
> exception for such long lines for this reason.
>
> Also, please don't put .'s on the end of log messages. It serves no 
> purpose and just adds to the log, the binary size and the source size. 
> There are quite a few of these.
>
> <snip>
>
> -- 
> Mark Rustad, MRustad@gmail.com

Re: [PATCH 2/2] IFC VDPA layer

[Zhu Lingshan]

On 11/8/2019 8:46 PM, Zhu Lingshan wrote:
>
> On 11/6/2019 6:39 PM, Jason Wang wrote:
>>
>> ----- Original Message -----
>>> This commit introduced IFC operations for vdpa, which complys to
>>> virtio_mdev and vhost_mdev interfaces, handles IFC VF
>>> initialization, configuration and removal.
>>>
>>> Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
>>> ---
>>>   drivers/vhost/ifcvf/ifcvf_main.c | 605
>>>   +++++++++++++++++++++++++++++++++++++++
>>>   1 file changed, 605 insertions(+)
>>>   create mode 100644 drivers/vhost/ifcvf/ifcvf_main.c
>>>
>>> diff --git a/drivers/vhost/ifcvf/ifcvf_main.c
>>> b/drivers/vhost/ifcvf/ifcvf_main.c
>>> new file mode 100644
>>> index 0000000..7165457
>>> --- /dev/null
>>> +++ b/drivers/vhost/ifcvf/ifcvf_main.c
>>> @@ -0,0 +1,605 @@
>>> +// SPDX-License-Identifier: GPL-2.0-only
>>> +/*
>>> + * Copyright (C) 2019 Intel Corporation.
>>> + */
>>> +
>>> +#include <linux/interrupt.h>
>>> +#include <linux/module.h>
>>> +#include <linux/mdev.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 struct ifcvf_hw *mdev_to_vf(struct mdev_device *mdev)
>>> +{
>>> +    struct ifcvf_asapter *adapter = mdev_get_drvdata(mdev);
>>> +    struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(adapter);
>>> +
>>> +    return vf;
>>> +}
>>> +
>>> +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 u64 ifcvf_mdev_get_features(struct mdev_device *mdev)
>>> +{
>>> +    struct ifcvf_hw *vf = mdev_to_vf(mdev);
>>> +
>>> +    return ifcvf_get_features(vf);
>>> +}
>>> +
>>> +static int ifcvf_mdev_set_features(struct mdev_device *mdev, u64 
>>> features)
>>> +{
>>> +    struct ifcvf_hw *vf = mdev_to_vf(mdev);
>>> +
>>> +    vf->req_features = features;
>>> +
>>> +    return 0;
>>> +}
>>> +
>>> +static u64 ifcvf_mdev_get_vq_state(struct mdev_device *mdev, u16 qid)
>>> +{
>>> +    struct ifcvf_hw *vf = mdev_to_vf(mdev);
>>> +    u16 last_avail_idx;
>>> +
>>> +    last_avail_idx = *(u16 *)(vf->lm_cfg + 
>>> IFCVF_LM_RING_STATE_OFFSET +
>>> +             (qid / 2) * IFCVF_LM_CFG_SIZE + (qid % 2) * 4);
>>> +
>> Similar to the comment of previous patch, it's better to have a
>> structure for lm_cfg.
>
> Hello Jason,
>
> Thanks for your comments!
>
> Now I use an variable for the address, and iowrite() for portable 
> purpose.
>
>>> +    return last_avail_idx;
>>> +}
>>> +
>>> +static int ifcvf_mdev_set_vq_state(struct mdev_device *mdev, u16 
>>> qid, u64
>>> num)
>>> +{
>>> +    struct ifcvf_hw *vf = mdev_to_vf(mdev);
>>> +
>>> +    vf->vring[qid].last_avail_idx = num;
>>> +
>>> +    return 0;
>>> +}
>>> +
>>> +static int ifcvf_mdev_set_vq_address(struct mdev_device *mdev, u16 
>>> idx,
>>> +                     u64 desc_area, u64 driver_area,
>>> +                     u64 device_area)
>>> +{
>>> +    struct ifcvf_hw *vf = mdev_to_vf(mdev);
>>> +
>>> +    vf->vring[idx].desc = desc_area;
>>> +    vf->vring[idx].avail = driver_area;
>>> +    vf->vring[idx].used = device_area;
>>> +
>>> +    return 0;
>>> +}
>>> +
>>> +static void ifcvf_mdev_set_vq_num(struct mdev_device *mdev, u16 
>>> qid, u32
>>> num)
>>> +{
>>> +    struct ifcvf_hw *vf = mdev_to_vf(mdev);
>>> +
>>> +    vf->vring[qid].size = num;
>>> +}
>>> +
>>> +static void ifcvf_mdev_set_vq_ready(struct mdev_device *mdev,
>>> +                    u16 qid, bool ready)
>>> +{
>>> +    struct ifcvf_hw *vf = mdev_to_vf(mdev);
>>> +
>>> +    vf->vring[qid].ready = ready;
>> There should be a "iowrite16(1, &cfg->queue_enable)" here. And there's
>> probably no need to store ready in vring in this case.
> Yes
>>
>>> +}
>>> +
>>> +static bool ifcvf_mdev_get_vq_ready(struct mdev_device *mdev, u16 qid)
>>> +{
>>> +    struct ifcvf_hw *vf = mdev_to_vf(mdev);
>>> +
>>> +    return vf->vring[qid].ready;
>> And the status should be read from cfg->queue_enable.
> Yes
>>
>>> +}
>>> +
>>> +static void ifcvf_mdev_set_vq_cb(struct mdev_device *mdev, u16 idx,
>>> +                 struct virtio_mdev_callback *cb)
>>> +{
>>> +    struct ifcvf_hw *vf = mdev_to_vf(mdev);
>>> +
>>> +    vf->vring[idx].cb = *cb;
>>> +}
>>> +
>>> +static void ifcvf_mdev_kick_vq(struct mdev_device *mdev, u16 idx)
>>> +{
>>> +    struct ifcvf_hw *vf = mdev_to_vf(mdev);
>>> +
>>> +    ifcvf_notify_queue(vf, idx);
>>> +}
>>> +
>>> +static u8 ifcvf_mdev_get_status(struct mdev_device *mdev)
>>> +{
>>> +    struct ifcvf_hw *vf = mdev_to_vf(mdev);
>>> +
>>> +    return ifcvf_get_status(vf);
>>> +}
>>> +
>>> +static u32 ifcvf_mdev_get_generation(struct mdev_device *mdev)
>>> +{
>>> +    struct ifcvf_hw *vf = mdev_to_vf(mdev);
>>> +
>>> +    return ioread8(&vf->common_cfg->config_generation);
>>> +}
>>> +
>>> +static u32 ifcvf_mdev_get_device_id(struct mdev_device *mdev)
>>> +{
>>> +    return VIRTIO_ID_NET;
>>> +}
>>> +
>>> +static u32 ifcvf_mdev_get_vendor_id(struct mdev_device *mdev)
>>> +{
>>> +    return IFCVF_VENDOR_ID;
>>> +}
>>> +
>>> +static u16 ifcvf_mdev_get_vq_align(struct mdev_device *mdev)
>>> +{
>>> +    return IFCVF_QUEUE_ALIGNMENT;
>>> +}
>>> +
>>> +static u64 ifcvf_mdev_get_mdev_features(struct mdev_device *mdev)
>>> +{
>>> +    return VIRTIO_MDEV_F_VERSION_1;
>>> +}
>> We've decide to remove this API.
> Removed.
>>
>>> +
>>> +static int ifcvf_start_datapath(void *private)
>>> +{
>>> +    struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(private);
>>> +    struct ifcvf_adapter *ifcvf;
>>> +    int i, ret = 0;
>>> +
>>> +    ifcvf = container_of(vf, struct ifcvf_adapter, vf);
>>> +
>>> +    for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++) {
>>> +        if (!vf->vring[i].ready) {
>>> +            IFC_ERR(ifcvf->dev,
>>> +                "Failed to start datapath, vring %d not ready.\n", i);
>>> +            return -EINVAL;
>>> +        }
>> This should be not related. Driver can choose to not start a virtqueue.
> removed the codes.
>>
>>> +
>>> +        if (!vf->vring[i].size) {
>>> +            IFC_ERR(ifcvf->dev,
>>> +                "Failed to start datapath, vring %d size is 
>>> zero.\n", i);
>>> +            return -EINVAL;
>>> +        }
>>> +
>>> +        if (!vf->vring[i].desc || !vf->vring[i].avail ||
>>> +            !vf->vring[i].used) {
>>> +            IFC_ERR(ifcvf->dev,
>>> +                "Failed to start datapath, "
>>> +                "invaild value for vring %d desc,"
>>> +                "avail_idx or usex_idx.\n", i);
>>> +            return -EINVAL;
>>> +        }
>>> +    }
>>> +
>>> +    vf->nr_vring = i;
>>> +    ret = ifcvf_start_hw(vf);
>> So basically there's no need for ifcvf_start_hw() to care about vq
>> enablement, virtio core will take care of that through set_vq_ready().
> Agreed, however if we don't enable the queue, I observe the hardware 
> will not allow access to the queue, even reading something.

Hello Jason,

IMHO, I think maybe we can keep using vring.ready. If upper layer want 
to enable the queue, it can call set_vq_ready to mark it as "ready", 
then ifcvf_hw_enable() will enable all queues marked as "ready"(I added 
some code there), this can give control to upper layer as well.

THanks!

>
>>
>>> +
>>> +    return ret;
>>> +}
>>> +
>>> +static int ifcvf_stop_datapath(void *private)
>>> +{
>>> +    struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(private);
>>> +    int i;
>>> +
>>> +    for (i = 0; i < IFCVF_MAX_QUEUES; 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 = IFC_PRIVATE_TO_VF(adapter);
>>> +    struct virtio_pci_common_cfg *cfg;
>>> +    u8 *lm_cfg;
>>> +    int i;
>>> +
>>> +    cfg = vf->common_cfg;
>>> +    lm_cfg = vf->lm_cfg;
>>> +
>>> +    for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++) {
>>> +        vf->vring[i].last_used_idx = 0;
>>> +        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->cb.callback = NULL;
>>> +        vf->vring->cb.private = NULL;
>>> +
>>> +    }
>>> +
>>> +    ifcvf_reset(vf);
>> So virtio-pci call vp_synchornize_vectors(), do need someting similar
>> here (I mean in ifcvf_reset())?
> Hardware handles most of the reset stuff, when reset the VF, we did 
> not free irqs, the handler still working, so the on-flight irqs can be 
> handled.
>>
>>> +}
>>> +
>>> +static void ifcvf_mdev_set_status(struct mdev_device *mdev, u8 status)
>>> +{
>>> +    struct ifcvf_adapter *adapter = mdev_get_drvdata(mdev);
>>> +    struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(adapter);
>>> +    int ret = 0;
>>> +
>>> +    if (status == 0) {
>>> +        ifcvf_stop_datapath(adapter);
>>> +        ifcvf_reset_vring(adapter);
>>> +        return;
>>> +    }
>>> +
>>> +    if (status & VIRTIO_CONFIG_S_DRIVER_OK) {
>>> +        ret = ifcvf_start_datapath(adapter);
>> If device support VIRTIO_CONFIG_S_DRIVER_OK, having something like
>> start_datapath here looks wired.
>>
>> If it just to setup the virtqueue etc, can we simply move them to e.g
>> set_vq_num, set_vq_address, etc?
> IMHO, it does not just setup vqs, it also do some config and enabling 
> works for the whole VF.
>>
>>> +
>>> +        if (ret)
>>> +            IFC_ERR(adapter->dev, "Failed to set mdev status %u.\n",
>>> +                status);
>>> +    }
>>> +
>>> +    ifcvf_set_status(vf, status);
>>> +}
>>> +
>>> +static u16 ifcvf_mdev_get_vq_num_max(struct mdev_device *mdev)
>>> +{
>>> +    struct ifcvf_hw *vf = mdev_to_vf(mdev);
>>> +
>>> +    return vf->vring[0].size;
>> It looks to me the only case that size is set is from
>> ifcvf_mdev_set_vq_num()? So I don't get how is this supposed to
>> work. I belive this should be a query for the hardware or a at least a
>> macro?
> Fixed.
>>
>>> +}
>>> +static void ifcvf_mdev_get_config(struct mdev_device *mdev, 
>>> unsigned int
>>> offset,
>>> +                 void *buf, unsigned int len)
>>> +{
>>> +    struct ifcvf_hw *vf = mdev_to_vf(mdev);
>>> +
>>> +    WARN_ON(offset + len > sizeof(struct ifcvf_net_config));
>>> +    ifcvf_read_net_config(vf, offset, buf, len);
>>> +}
>>> +
>>> +static void ifcvf_mdev_set_config(struct mdev_device *mdev, 
>>> unsigned int
>>> offset,
>>> +                 const void *buf, unsigned int len)
>>> +{
>>> +    struct ifcvf_hw *vf = mdev_to_vf(mdev);
>>> +
>>> +    WARN_ON(offset + len > sizeof(struct ifcvf_net_config));
>>> +    ifcvf_write_net_config(vf, offset, buf, len);
>>> +}
>>> +
>>> +static struct virtio_mdev_device_ops ifc_mdev_ops = {
>>> +    .get_features  = ifcvf_mdev_get_features,
>>> +    .set_features  = ifcvf_mdev_set_features,
>>> +    .get_status    = ifcvf_mdev_get_status,
>>> +    .set_status    = ifcvf_mdev_set_status,
>>> +    .get_vq_num_max = ifcvf_mdev_get_vq_num_max,
>>> +    .get_vq_state   = ifcvf_mdev_get_vq_state,
>>> +    .set_vq_state   = ifcvf_mdev_set_vq_state,
>>> +    .set_vq_cb      = ifcvf_mdev_set_vq_cb,
>>> +    .set_vq_ready   = ifcvf_mdev_set_vq_ready,
>>> +    .get_vq_ready    = ifcvf_mdev_get_vq_ready,
>>> +    .set_vq_num     = ifcvf_mdev_set_vq_num,
>>> +    .set_vq_address = ifcvf_mdev_set_vq_address,
>>> +    .kick_vq        = ifcvf_mdev_kick_vq,
>>> +    .get_generation    = ifcvf_mdev_get_generation,
>>> +    .get_device_id    = ifcvf_mdev_get_device_id,
>>> +    .get_vendor_id    = ifcvf_mdev_get_vendor_id,
>>> +    .get_vq_align    = ifcvf_mdev_get_vq_align,
>>> +    .get_config    = ifcvf_mdev_get_config,
>>> +    .set_config    = ifcvf_mdev_set_config,
>>> +    .get_mdev_features = ifcvf_mdev_get_mdev_features,
>> set_config_cb needs to be implemented since you claim to support 
>> VIRTIO_NET_F_STATUS.
> control_vq feature bit is removed.
>>
>>> +};
>>> +
>>> +static int ifcvf_init_msix(struct ifcvf_adapter *adapter)
>>> +{
>>> +    struct pci_dev *pdev = to_pci_dev(adapter->dev);
>>> +    struct ifcvf_hw *vf = &adapter->vf;
>>> +    int vector, i, ret, irq;
>>> +
>>> +    ret = pci_alloc_irq_vectors(pdev, IFCVF_MAX_INTR,
>>> +                    IFCVF_MAX_INTR, PCI_IRQ_MSIX);
>>> +    if (ret < 0) {
>>> +        IFC_ERR(adapter->dev, "Failed to alloc irq vectors.\n");
>>> +        return ret;
>>> +    }
>>> +
>>> +    for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++) {
>>> +        vector = i + IFCVF_MSI_QUEUE_OFF;
>>> +        irq = pci_irq_vector(pdev, vector);
>>> +        ret = request_irq(irq, ifcvf_intr_handler, 0,
>>> +                pci_name(pdev), &vf->vring[i]);
>>> +        if (ret) {
>>> +            IFC_ERR(adapter->dev,
>>> +                "Failed to request irq for vq %d.\n", i);
>>> +            return ret;
>>> +        }
>>> +    }
>> Need allocate config interrupt here as well.
>>
>>> +
>>> +    return 0;
>>> +}
>>> +
>>> +static void ifcvf_destroy_adapter(struct ifcvf_adapter *adapter)
>>> +{
>>> +    struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(adapter);
>>> +    struct pci_dev *pdev = to_pci_dev(adapter->dev);
>>> +    int i, vector, irq;
>>> +
>>> +    for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++) {
>>> +        vector = i + IFCVF_MSI_QUEUE_OFF;
>>> +        irq = pci_irq_vector(pdev, vector);
>>> +        free_irq(irq, &vf->vring[i]);
>>> +    }
>>> +}
>>> +
>>> +static ssize_t name_show(struct kobject *kobj, struct device *dev, 
>>> char
>>> *buf)
>>> +{
>>> +    const char *name = "vhost accelerator (virtio ring compatible)";
>>> +
>> I believe something like "IFCVF vhost/virtio accelerator" is better?
> Agreed.
>>
>>> +    return sprintf(buf, "%s\n", name);
>>> +}
>>> +MDEV_TYPE_ATTR_RO(name);
>>> +
>>> +static ssize_t device_api_show(struct kobject *kobj, struct device 
>>> *dev,
>>> +                   char *buf)
>>> +{
>>> +    return sprintf(buf, "%s\n", VIRTIO_MDEV_DEVICE_API_STRING);
>>> +}
>>> +MDEV_TYPE_ATTR_RO(device_api);
>>> +
>>> +static ssize_t available_instances_show(struct kobject *kobj,
>>> +                    struct device *dev, char *buf)
>>> +{
>>> +    struct pci_dev *pdev;
>>> +    struct ifcvf_adapter *adapter;
>>> +
>>> +    pdev = to_pci_dev(dev);
>>> +    adapter = pci_get_drvdata(pdev);
>>> +
>>> +    return sprintf(buf, "%d\n", adapter->mdev_count);
>>> +}
>>> +
>>> +MDEV_TYPE_ATTR_RO(available_instances);
>>> +
>>> +static ssize_t type_show(struct kobject *kobj,
>>> +            struct device *dev, char *buf)
>>> +{
>>> +    return sprintf(buf, "%s\n", "net");
>>> +}
>>> +
>>> +MDEV_TYPE_ATTR_RO(type);
>>> +
>>> +
>>> +static struct attribute *mdev_types_attrs[] = {
>>> +    &mdev_type_attr_name.attr,
>>> +    &mdev_type_attr_device_api.attr,
>>> +    &mdev_type_attr_available_instances.attr,
>>> +    &mdev_type_attr_type.attr,
>>> +    NULL,
>>> +};
>>> +
>>> +static struct attribute_group mdev_type_group_virtio = {
>>> +    .name  = "virtio_mdev",
>>> +    .attrs = mdev_types_attrs,
>>> +};
>>> +
>>> +static struct attribute_group mdev_type_group_vhost = {
>>> +    .name  = "vhost_mdev",
>>> +    .attrs = mdev_types_attrs,
>>> +};
>>> +
>>> +static struct attribute_group *mdev_type_groups[] = {
>>> +    &mdev_type_group_virtio,
>>> +    &mdev_type_group_vhost,
>>> +    NULL,
>>> +};
>>> +
>>> +const struct attribute_group *mdev_dev_groups[] = {
>>> +    NULL,
>>> +};
>>> +
>>> +static int ifcvf_mdev_create(struct kobject *kobj, struct 
>>> mdev_device *mdev)
>>> +{
>>> +    struct device *dev = mdev_parent_dev(mdev);
>>> +    struct pci_dev *pdev = to_pci_dev(dev);
>>> +    struct ifcvf_adapter *adapter = pci_get_drvdata(pdev);
>>> +    int ret = 0;
>>> +
>>> +    mutex_lock(&adapter->mdev_lock);
>>> +
>>> +    if (adapter->mdev_count < IFCVF_MDEV_LIMIT) {
>>> +        IFC_ERR(&pdev->dev,
>>> +            "Can not create mdev, reached limitation %d.\n",
>>> +            IFCVF_MDEV_LIMIT);
>>> +        ret = -EINVAL;
>>> +        goto out;
>>> +    }
>>> +
>>> +    if (!strcmp(kobj->name, "ifcvf-virtio_mdev"))
>>> +        mdev_set_virtio_ops(mdev, &ifc_mdev_ops);
>>> +
>>> +    if (!strcmp(kobj->name, "ifcvf-vhost_mdev"))
>>> +        mdev_set_vhost_ops(mdev, &ifc_mdev_ops);
>>> +
>>> +    mdev_set_drvdata(mdev, adapter);
>>> +    mdev_set_iommu_device(mdev_dev(mdev), dev);
>>> +    adapter->mdev_count--;
>>> +
>>> +out:
>>> +    mutex_unlock(&adapter->mdev_lock);
>>> +    return ret;
>>> +}
>>> +
>>> +static int ifcvf_mdev_remove(struct mdev_device *mdev)
>>> +{
>>> +    struct device *dev = mdev_parent_dev(mdev);
>>> +    struct pci_dev *pdev = to_pci_dev(dev);
>>> +    struct ifcvf_adapter *adapter = pci_get_drvdata(pdev);
>>> +
>>> +    mutex_lock(&adapter->mdev_lock);
>>> +    adapter->mdev_count++;
>>> +    mutex_unlock(&adapter->mdev_lock);
>>> +
>>> +    return 0;
>>> +}
>>> +
>>> +static struct mdev_parent_ops ifcvf_mdev_fops = {
>>> +    .owner            = THIS_MODULE,
>>> +    .supported_type_groups    = mdev_type_groups,
>>> +    .mdev_attr_groups    = mdev_dev_groups,
>>> +    .create            = ifcvf_mdev_create,
>>> +    .remove            = ifcvf_mdev_remove,
>>> +};
>>> +
>>> +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, i;
>>> +
>>> +    adapter = kzalloc(sizeof(struct ifcvf_adapter), GFP_KERNEL);
>>> +
>>> +    if (adapter == NULL) {
>>> +        ret = -ENOMEM;
>>> +        goto fail;
>>> +    }
>>> +
>>> +    mutex_init(&adapter->mdev_lock);
>>> +    adapter->mdev_count = IFCVF_MDEV_LIMIT;
>>> +    adapter->dev = dev;
>>> +    pci_set_drvdata(pdev, adapter);
>>> +    ret = pci_enable_device(pdev);
>>> +
>>> +    if (ret) {
>>> +        IFC_ERR(adapter->dev, "Failed to enable device.\n");
>>> +        goto free_adapter;
>>> +    }
>>> +
>>> +    ret = pci_request_regions(pdev, IFCVF_DRIVER_NAME);
>>> +
>>> +    if (ret) {
>>> +        IFC_ERR(adapter->dev, "Failed to request MMIO region.\n");
>>> +        goto disable_device;
>>> +    }
>>> +
>>> +    pci_set_master(pdev);
>>> +    ret = ifcvf_init_msix(adapter);
>>> +
>>> +    if (ret) {
>>> +        IFC_ERR(adapter->dev, "Failed to initialize MSIX.\n");
>>> +        goto free_msix;
>>> +    }
>>> +
>>> +    vf = &adapter->vf;
>>> +
>>> +    for (i = 0; i < IFCVF_PCI_MAX_RESOURCE; i++) {
>>> +        vf->mem_resource[i].phys_addr = pci_resource_start(pdev, i);
>>> +        vf->mem_resource[i].len = pci_resource_len(pdev, i);
>>> +        if (!vf->mem_resource[i].len) {
>>> +            vf->mem_resource[i].addr = NULL;
>>> +            continue;
>>> +        }
>>> +
>>> +        vf->mem_resource[i].addr = pci_iomap_range(pdev, i, 0,
>>> +                vf->mem_resource[i].len);
>>> +        if (!vf->mem_resource[i].addr) {
>>> +            IFC_ERR(adapter->dev, "Failed to map IO resource %d\n",
>>> +                i);
>>> +            ret = -1;
>>> +            goto free_msix;
>>> +        }
>>> +    }
>>> +
>>> +    if (ifcvf_init_hw(vf, pdev) < 0) {
>>> +        ret = -1;
>>> +        goto destroy_adapter;
>>> +    }
>>> +
>>> +    ret = mdev_register_device(dev, &ifcvf_mdev_fops);
>>> +
>>> +    if (ret) {
>>> +        IFC_ERR(adapter->dev,  "Failed to register mdev device\n");
>>> +        goto destroy_adapter;
>>> +    }
>>> +
>>> +    return 0;
>>> +
>>> +destroy_adapter:
>>> +    ifcvf_destroy_adapter(adapter);
>>> +free_msix:
>>> +    pci_free_irq_vectors(pdev);
>>> +    pci_release_regions(pdev);
>>> +disable_device:
>>> +    pci_disable_device(pdev);
>>> +free_adapter:
>>> +    kfree(adapter);
>>> +fail:
>>> +    return ret;
>>> +}
>>> +
>>> +static void ifcvf_remove(struct pci_dev *pdev)
>>> +{
>>> +    struct ifcvf_adapter *adapter = pci_get_drvdata(pdev);
>>> +    struct device *dev = &pdev->dev;
>>> +    struct ifcvf_hw *vf;
>>> +    int i;
>>> +
>>> +    mdev_unregister_device(dev);
>>> +
>>> +    vf = &adapter->vf;
>>> +    for (i = 0; i < IFCVF_PCI_MAX_RESOURCE; i++) {
>>> +        if (vf->mem_resource[i].addr) {
>>> +            pci_iounmap(pdev, vf->mem_resource[i].addr);
>>> +            vf->mem_resource[i].addr = NULL;
>>> +        }
>>> +    }
>>> +
>>> +    ifcvf_destroy_adapter(adapter);
>>> +    pci_free_irq_vectors(pdev);
>>> +    pci_release_regions(pdev);
>>> +    pci_disable_device(pdev);
>>> +    kfree(adapter);
>>> +}
>>> +
>>> +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,
>>> +};
>>> +
>>> +static int __init ifcvf_init_module(void)
>>> +{
>>> +    int ret;
>>> +
>>> +    ret = pci_register_driver(&ifcvf_driver);
>>> +    return ret;
>>> +}
>>> +
>>> +static void __exit ifcvf_exit_module(void)
>>> +{
>>> +    pci_unregister_driver(&ifcvf_driver);
>>> +}
>> You probably can do something simpler thorugh module_pci_driver().
>>
>> Thanks
>>
>>> +
>>> +module_init(ifcvf_init_module);
>>> +module_exit(ifcvf_exit_module);
>>> +
>>> +MODULE_LICENSE("GPL v2");
>>> +MODULE_VERSION(VERSION_STRING);
>>> +MODULE_AUTHOR(DRIVER_AUTHOR);
>>> -- 
>>> 1.8.3.1
>>>
>>>