From 30326f9577342aac257ed9c036608de666b06389 Mon Sep 17 00:00:00 2001
From: Zhu Lingshan <lingshan.zhu@intel.com>
Date: Thu, 12 Aug 2021 11:24:53 +0800
Subject: vDPA/ifcvf: introduce get_dev_type() which returns virtio dev id

This commit introduces a new function get_dev_type() which returns
the virtio device id of a device, to avoid duplicated code.

Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20210812032454.24486-2-lingshan.zhu@intel.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
 drivers/vdpa/ifcvf/ifcvf_main.c | 34 +++++++++++++++++++++-------------
 1 file changed, 21 insertions(+), 13 deletions(-)

(limited to 'drivers/vdpa')

diff --git a/drivers/vdpa/ifcvf/ifcvf_main.c b/drivers/vdpa/ifcvf/ifcvf_main.c
index 351c6cfb24c3..52465b7b0114 100644
--- a/drivers/vdpa/ifcvf/ifcvf_main.c
+++ b/drivers/vdpa/ifcvf/ifcvf_main.c
@@ -458,6 +458,26 @@ static const struct vdpa_config_ops ifc_vdpa_ops = {
 	.get_vq_notification = ifcvf_get_vq_notification,
 };
 
+static u32 get_dev_type(struct pci_dev *pdev)
+{
+	u32 dev_type;
+
+	/* This drirver drives both modern virtio devices and transitional
+	 * devices in modern mode.
+	 * vDPA requires feature bit VIRTIO_F_ACCESS_PLATFORM,
+	 * so legacy devices and transitional devices in legacy
+	 * mode will not work for vDPA, this driver will not
+	 * drive devices with legacy interface.
+	 */
+
+	if (pdev->device < 0x1040)
+		dev_type =  pdev->subsystem_device;
+	else
+		dev_type =  pdev->device - 0x1040;
+
+	return dev_type;
+}
+
 static int ifcvf_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 {
 	struct device *dev = &pdev->dev;
@@ -502,19 +522,7 @@ static int ifcvf_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 	pci_set_drvdata(pdev, adapter);
 
 	vf = &adapter->vf;
-
-	/* This drirver drives both modern virtio devices and transitional
-	 * devices in modern mode.
-	 * vDPA requires feature bit VIRTIO_F_ACCESS_PLATFORM,
-	 * so legacy devices and transitional devices in legacy
-	 * mode will not work for vDPA, this driver will not
-	 * drive devices with legacy interface.
-	 */
-	if (pdev->device < 0x1040)
-		vf->dev_type =  pdev->subsystem_device;
-	else
-		vf->dev_type =  pdev->device - 0x1040;
-
+	vf->dev_type = get_dev_type(pdev);
 	vf->base = pcim_iomap_table(pdev);
 
 	adapter->pdev = pdev;
-- 
cgit v1.2.3


From 6b5df347c6482f57b0d8f0569b86fb8fcd90d168 Mon Sep 17 00:00:00 2001
From: Zhu Lingshan <lingshan.zhu@intel.com>
Date: Thu, 12 Aug 2021 11:24:54 +0800
Subject: vDPA/ifcvf: implement management netlink framework for ifcvf

This commit implements the management netlink framework for ifcvf,
including register and add / remove a device

It works with iproute2:
[root@localhost lszhu]# vdpa mgmtdev show -jp
{
    "mgmtdev": {
        "pci/0000:01:00.5": {
            "supported_classes": [ "net" ]
        },
        "pci/0000:01:00.6": {
            "supported_classes": [ "net" ]
        }
    }
}

[root@localhost lszhu]# vdpa dev add mgmtdev pci/0000:01:00.5 name vdpa0
[root@localhost lszhu]# vdpa dev add mgmtdev pci/0000:01:00.6 name vdpa1

Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20210812032454.24486-3-lingshan.zhu@intel.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
 drivers/vdpa/ifcvf/ifcvf_base.h |   6 ++
 drivers/vdpa/ifcvf/ifcvf_main.c | 152 +++++++++++++++++++++++++++++++---------
 2 files changed, 123 insertions(+), 35 deletions(-)

(limited to 'drivers/vdpa')

diff --git a/drivers/vdpa/ifcvf/ifcvf_base.h b/drivers/vdpa/ifcvf/ifcvf_base.h
index 2996db0da490..1601e87870da 100644
--- a/drivers/vdpa/ifcvf/ifcvf_base.h
+++ b/drivers/vdpa/ifcvf/ifcvf_base.h
@@ -106,6 +106,12 @@ struct ifcvf_lm_cfg {
 	struct ifcvf_vring_lm_cfg vring_lm_cfg[IFCVF_MAX_QUEUE_PAIRS];
 };
 
+struct ifcvf_vdpa_mgmt_dev {
+	struct vdpa_mgmt_dev mdev;
+	struct ifcvf_adapter *adapter;
+	struct pci_dev *pdev;
+};
+
 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);
diff --git a/drivers/vdpa/ifcvf/ifcvf_main.c b/drivers/vdpa/ifcvf/ifcvf_main.c
index 52465b7b0114..e9a92b31dcc5 100644
--- a/drivers/vdpa/ifcvf/ifcvf_main.c
+++ b/drivers/vdpa/ifcvf/ifcvf_main.c
@@ -218,7 +218,7 @@ static void ifcvf_vdpa_set_status(struct vdpa_device *vdpa_dev, u8 status)
 	int ret;
 
 	vf  = vdpa_to_vf(vdpa_dev);
-	adapter = dev_get_drvdata(vdpa_dev->dev.parent);
+	adapter = vdpa_to_adapter(vdpa_dev);
 	status_old = ifcvf_get_status(vf);
 
 	if (status_old == status)
@@ -458,6 +458,16 @@ static const struct vdpa_config_ops ifc_vdpa_ops = {
 	.get_vq_notification = ifcvf_get_vq_notification,
 };
 
+static struct virtio_device_id id_table_net[] = {
+	{VIRTIO_ID_NET, VIRTIO_DEV_ANY_ID},
+	{0},
+};
+
+static struct virtio_device_id id_table_blk[] = {
+	{VIRTIO_ID_BLOCK, VIRTIO_DEV_ANY_ID},
+	{0},
+};
+
 static u32 get_dev_type(struct pci_dev *pdev)
 {
 	u32 dev_type;
@@ -478,48 +488,30 @@ static u32 get_dev_type(struct pci_dev *pdev)
 	return dev_type;
 }
 
-static int ifcvf_probe(struct pci_dev *pdev, const struct pci_device_id *id)
+static int ifcvf_vdpa_dev_add(struct vdpa_mgmt_dev *mdev, const char *name)
 {
-	struct device *dev = &pdev->dev;
+	struct ifcvf_vdpa_mgmt_dev *ifcvf_mgmt_dev;
 	struct ifcvf_adapter *adapter;
+	struct pci_dev *pdev;
 	struct ifcvf_hw *vf;
+	struct device *dev;
 	int ret, i;
 
-	ret = pcim_enable_device(pdev);
-	if (ret) {
-		IFCVF_ERR(pdev, "Failed to enable device\n");
-		return ret;
-	}
-
-	ret = pcim_iomap_regions(pdev, BIT(0) | BIT(2) | BIT(4),
-				 IFCVF_DRIVER_NAME);
-	if (ret) {
-		IFCVF_ERR(pdev, "Failed to request MMIO region\n");
-		return ret;
-	}
-
-	ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(64));
-	if (ret) {
-		IFCVF_ERR(pdev, "No usable DMA configuration\n");
-		return ret;
-	}
-
-	ret = devm_add_action_or_reset(dev, ifcvf_free_irq_vectors, pdev);
-	if (ret) {
-		IFCVF_ERR(pdev,
-			  "Failed for adding devres for freeing irq vectors\n");
-		return ret;
-	}
+	ifcvf_mgmt_dev = container_of(mdev, struct ifcvf_vdpa_mgmt_dev, mdev);
+	if (ifcvf_mgmt_dev->adapter)
+		return -EOPNOTSUPP;
 
+	pdev = ifcvf_mgmt_dev->pdev;
+	dev = &pdev->dev;
 	adapter = vdpa_alloc_device(struct ifcvf_adapter, vdpa,
-				    dev, &ifc_vdpa_ops, NULL);
+				    dev, &ifc_vdpa_ops, name);
 	if (IS_ERR(adapter)) {
 		IFCVF_ERR(pdev, "Failed to allocate vDPA structure");
 		return PTR_ERR(adapter);
 	}
 
-	pci_set_master(pdev);
-	pci_set_drvdata(pdev, adapter);
+	ifcvf_mgmt_dev->adapter = adapter;
+	pci_set_drvdata(pdev, ifcvf_mgmt_dev);
 
 	vf = &adapter->vf;
 	vf->dev_type = get_dev_type(pdev);
@@ -539,9 +531,10 @@ static int ifcvf_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 
 	vf->hw_features = ifcvf_get_hw_features(vf);
 
-	ret = vdpa_register_device(&adapter->vdpa, IFCVF_MAX_QUEUE_PAIRS * 2);
+	adapter->vdpa.mdev = &ifcvf_mgmt_dev->mdev;
+	ret = _vdpa_register_device(&adapter->vdpa, IFCVF_MAX_QUEUE_PAIRS * 2);
 	if (ret) {
-		IFCVF_ERR(pdev, "Failed to register ifcvf to vdpa bus");
+		IFCVF_ERR(pdev, "Failed to register to vDPA bus");
 		goto err;
 	}
 
@@ -552,11 +545,100 @@ err:
 	return ret;
 }
 
+static void ifcvf_vdpa_dev_del(struct vdpa_mgmt_dev *mdev, struct vdpa_device *dev)
+{
+	struct ifcvf_vdpa_mgmt_dev *ifcvf_mgmt_dev;
+
+	ifcvf_mgmt_dev = container_of(mdev, struct ifcvf_vdpa_mgmt_dev, mdev);
+	_vdpa_unregister_device(dev);
+	ifcvf_mgmt_dev->adapter = NULL;
+}
+
+static const struct vdpa_mgmtdev_ops ifcvf_vdpa_mgmt_dev_ops = {
+	.dev_add = ifcvf_vdpa_dev_add,
+	.dev_del = ifcvf_vdpa_dev_del
+};
+
+static int ifcvf_probe(struct pci_dev *pdev, const struct pci_device_id *id)
+{
+	struct ifcvf_vdpa_mgmt_dev *ifcvf_mgmt_dev;
+	struct device *dev = &pdev->dev;
+	u32 dev_type;
+	int ret;
+
+	ifcvf_mgmt_dev = kzalloc(sizeof(struct ifcvf_vdpa_mgmt_dev), GFP_KERNEL);
+	if (!ifcvf_mgmt_dev) {
+		IFCVF_ERR(pdev, "Failed to alloc memory for the vDPA management device\n");
+		return -ENOMEM;
+	}
+
+	dev_type = get_dev_type(pdev);
+	switch (dev_type) {
+	case VIRTIO_ID_NET:
+		ifcvf_mgmt_dev->mdev.id_table = id_table_net;
+		break;
+	case VIRTIO_ID_BLOCK:
+		ifcvf_mgmt_dev->mdev.id_table = id_table_blk;
+		break;
+	default:
+		IFCVF_ERR(pdev, "VIRTIO ID %u not supported\n", dev_type);
+		ret = -EOPNOTSUPP;
+		goto err;
+	}
+
+	ifcvf_mgmt_dev->mdev.ops = &ifcvf_vdpa_mgmt_dev_ops;
+	ifcvf_mgmt_dev->mdev.device = dev;
+	ifcvf_mgmt_dev->pdev = pdev;
+
+	ret = pcim_enable_device(pdev);
+	if (ret) {
+		IFCVF_ERR(pdev, "Failed to enable device\n");
+		goto err;
+	}
+
+	ret = pcim_iomap_regions(pdev, BIT(0) | BIT(2) | BIT(4),
+				 IFCVF_DRIVER_NAME);
+	if (ret) {
+		IFCVF_ERR(pdev, "Failed to request MMIO region\n");
+		goto err;
+	}
+
+	ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(64));
+	if (ret) {
+		IFCVF_ERR(pdev, "No usable DMA configuration\n");
+		goto err;
+	}
+
+	ret = devm_add_action_or_reset(dev, ifcvf_free_irq_vectors, pdev);
+	if (ret) {
+		IFCVF_ERR(pdev,
+			  "Failed for adding devres for freeing irq vectors\n");
+		goto err;
+	}
+
+	pci_set_master(pdev);
+
+	ret = vdpa_mgmtdev_register(&ifcvf_mgmt_dev->mdev);
+	if (ret) {
+		IFCVF_ERR(pdev,
+			  "Failed to initialize the management interfaces\n");
+		goto err;
+	}
+
+	return 0;
+
+err:
+	kfree(ifcvf_mgmt_dev);
+	return ret;
+}
+
 static void ifcvf_remove(struct pci_dev *pdev)
 {
-	struct ifcvf_adapter *adapter = pci_get_drvdata(pdev);
+	struct ifcvf_vdpa_mgmt_dev *ifcvf_mgmt_dev;
 
-	vdpa_unregister_device(&adapter->vdpa);
+	ifcvf_mgmt_dev = pci_get_drvdata(pdev);
+	vdpa_mgmtdev_unregister(&ifcvf_mgmt_dev->mdev);
+	kfree(ifcvf_mgmt_dev);
 }
 
 static struct pci_device_id ifcvf_pci_ids[] = {
-- 
cgit v1.2.3


From 2ddae773c93bbcb0678ae819551f1750a505edec Mon Sep 17 00:00:00 2001
From: Zhu Lingshan <lingshan.zhu@intel.com>
Date: Wed, 18 Aug 2021 17:57:13 +0800
Subject: vDPA/ifcvf: detect and use the onboard number of queues directly

To enable this multi-queue feature for ifcvf, this commit
intends to detect and use the onboard number of queues
directly than IFCVF_MAX_QUEUE_PAIRS = 1 (removed)

Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
Link: https://lore.kernel.org/r/20210818095714.3220-2-lingshan.zhu@intel.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
---
 drivers/vdpa/ifcvf/ifcvf_base.c |  8 +++++---
 drivers/vdpa/ifcvf/ifcvf_base.h | 10 ++++------
 drivers/vdpa/ifcvf/ifcvf_main.c | 21 ++++++++++++---------
 3 files changed, 21 insertions(+), 18 deletions(-)

(limited to 'drivers/vdpa')

diff --git a/drivers/vdpa/ifcvf/ifcvf_base.c b/drivers/vdpa/ifcvf/ifcvf_base.c
index 6e197fe0fcf9..2808f1ba9f7b 100644
--- a/drivers/vdpa/ifcvf/ifcvf_base.c
+++ b/drivers/vdpa/ifcvf/ifcvf_base.c
@@ -158,7 +158,9 @@ next:
 		return -EIO;
 	}
 
-	for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++) {
+	hw->nr_vring = ifc_ioread16(&hw->common_cfg->num_queues);
+
+	for (i = 0; i < hw->nr_vring; i++) {
 		ifc_iowrite16(i, &hw->common_cfg->queue_select);
 		notify_off = ifc_ioread16(&hw->common_cfg->queue_notify_off);
 		hw->vring[i].notify_addr = hw->notify_base +
@@ -304,7 +306,7 @@ u16 ifcvf_get_vq_state(struct ifcvf_hw *hw, u16 qid)
 	u32 q_pair_id;
 
 	ifcvf_lm = (struct ifcvf_lm_cfg __iomem *)hw->lm_cfg;
-	q_pair_id = qid / (IFCVF_MAX_QUEUE_PAIRS * 2);
+	q_pair_id = qid / hw->nr_vring;
 	avail_idx_addr = &ifcvf_lm->vring_lm_cfg[q_pair_id].idx_addr[qid % 2];
 	last_avail_idx = ifc_ioread16(avail_idx_addr);
 
@@ -318,7 +320,7 @@ int ifcvf_set_vq_state(struct ifcvf_hw *hw, u16 qid, u16 num)
 	u32 q_pair_id;
 
 	ifcvf_lm = (struct ifcvf_lm_cfg __iomem *)hw->lm_cfg;
-	q_pair_id = qid / (IFCVF_MAX_QUEUE_PAIRS * 2);
+	q_pair_id = qid / hw->nr_vring;
 	avail_idx_addr = &ifcvf_lm->vring_lm_cfg[q_pair_id].idx_addr[qid % 2];
 	hw->vring[qid].last_avail_idx = num;
 	ifc_iowrite16(num, avail_idx_addr);
diff --git a/drivers/vdpa/ifcvf/ifcvf_base.h b/drivers/vdpa/ifcvf/ifcvf_base.h
index 1601e87870da..97d9019a3ec0 100644
--- a/drivers/vdpa/ifcvf/ifcvf_base.h
+++ b/drivers/vdpa/ifcvf/ifcvf_base.h
@@ -31,8 +31,8 @@
 		 (1ULL << VIRTIO_F_ACCESS_PLATFORM)		| \
 		 (1ULL << VIRTIO_NET_F_MRG_RXBUF))
 
-/* Only one queue pair for now. */
-#define IFCVF_MAX_QUEUE_PAIRS	1
+/* Max 8 data queue pairs(16 queues) and one control vq for now. */
+#define IFCVF_MAX_QUEUES	17
 
 #define IFCVF_QUEUE_ALIGNMENT	PAGE_SIZE
 #define IFCVF_QUEUE_MAX		32768
@@ -51,8 +51,6 @@
 #define ifcvf_private_to_vf(adapter) \
 	(&((struct ifcvf_adapter *)adapter)->vf)
 
-#define IFCVF_MAX_INTR (IFCVF_MAX_QUEUE_PAIRS * 2 + 1)
-
 struct vring_info {
 	u64 desc;
 	u64 avail;
@@ -83,7 +81,7 @@ struct ifcvf_hw {
 	u32 dev_type;
 	struct virtio_pci_common_cfg __iomem *common_cfg;
 	void __iomem *net_cfg;
-	struct vring_info vring[IFCVF_MAX_QUEUE_PAIRS * 2];
+	struct vring_info vring[IFCVF_MAX_QUEUES];
 	void __iomem * const *base;
 	char config_msix_name[256];
 	struct vdpa_callback config_cb;
@@ -103,7 +101,7 @@ struct ifcvf_vring_lm_cfg {
 
 struct ifcvf_lm_cfg {
 	u8 reserved[IFCVF_LM_RING_STATE_OFFSET];
-	struct ifcvf_vring_lm_cfg vring_lm_cfg[IFCVF_MAX_QUEUE_PAIRS];
+	struct ifcvf_vring_lm_cfg vring_lm_cfg[IFCVF_MAX_QUEUES];
 };
 
 struct ifcvf_vdpa_mgmt_dev {
diff --git a/drivers/vdpa/ifcvf/ifcvf_main.c b/drivers/vdpa/ifcvf/ifcvf_main.c
index e9a92b31dcc5..37675c93b1ff 100644
--- a/drivers/vdpa/ifcvf/ifcvf_main.c
+++ b/drivers/vdpa/ifcvf/ifcvf_main.c
@@ -63,9 +63,13 @@ static int ifcvf_request_irq(struct ifcvf_adapter *adapter)
 	struct pci_dev *pdev = adapter->pdev;
 	struct ifcvf_hw *vf = &adapter->vf;
 	int vector, i, ret, irq;
+	u16 max_intr;
 
-	ret = pci_alloc_irq_vectors(pdev, IFCVF_MAX_INTR,
-				    IFCVF_MAX_INTR, PCI_IRQ_MSIX);
+	/* all queues and config interrupt  */
+	max_intr = vf->nr_vring + 1;
+
+	ret = pci_alloc_irq_vectors(pdev, max_intr,
+				    max_intr, PCI_IRQ_MSIX);
 	if (ret < 0) {
 		IFCVF_ERR(pdev, "Failed to alloc IRQ vectors\n");
 		return ret;
@@ -83,7 +87,7 @@ static int ifcvf_request_irq(struct ifcvf_adapter *adapter)
 		return ret;
 	}
 
-	for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++) {
+	for (i = 0; i < vf->nr_vring; i++) {
 		snprintf(vf->vring[i].msix_name, 256, "ifcvf[%s]-%d\n",
 			 pci_name(pdev), i);
 		vector = i + IFCVF_MSI_QUEUE_OFF;
@@ -112,7 +116,6 @@ static int ifcvf_start_datapath(void *private)
 	u8 status;
 	int ret;
 
-	vf->nr_vring = IFCVF_MAX_QUEUE_PAIRS * 2;
 	ret = ifcvf_start_hw(vf);
 	if (ret < 0) {
 		status = ifcvf_get_status(vf);
@@ -128,7 +131,7 @@ static int ifcvf_stop_datapath(void *private)
 	struct ifcvf_hw *vf = ifcvf_private_to_vf(private);
 	int i;
 
-	for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++)
+	for (i = 0; i < vf->nr_vring; i++)
 		vf->vring[i].cb.callback = NULL;
 
 	ifcvf_stop_hw(vf);
@@ -141,7 +144,7 @@ static void ifcvf_reset_vring(struct ifcvf_adapter *adapter)
 	struct ifcvf_hw *vf = ifcvf_private_to_vf(adapter);
 	int i;
 
-	for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++) {
+	for (i = 0; i < vf->nr_vring; i++) {
 		vf->vring[i].last_avail_idx = 0;
 		vf->vring[i].desc = 0;
 		vf->vring[i].avail = 0;
@@ -227,7 +230,7 @@ static void ifcvf_vdpa_set_status(struct vdpa_device *vdpa_dev, u8 status)
 	if ((status_old & VIRTIO_CONFIG_S_DRIVER_OK) &&
 	    !(status & VIRTIO_CONFIG_S_DRIVER_OK)) {
 		ifcvf_stop_datapath(adapter);
-		ifcvf_free_irq(adapter, IFCVF_MAX_QUEUE_PAIRS * 2);
+		ifcvf_free_irq(adapter, vf->nr_vring);
 	}
 
 	if (status == 0) {
@@ -526,13 +529,13 @@ static int ifcvf_vdpa_dev_add(struct vdpa_mgmt_dev *mdev, const char *name)
 		goto err;
 	}
 
-	for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++)
+	for (i = 0; i < vf->nr_vring; i++)
 		vf->vring[i].irq = -EINVAL;
 
 	vf->hw_features = ifcvf_get_hw_features(vf);
 
 	adapter->vdpa.mdev = &ifcvf_mgmt_dev->mdev;
-	ret = _vdpa_register_device(&adapter->vdpa, IFCVF_MAX_QUEUE_PAIRS * 2);
+	ret = _vdpa_register_device(&adapter->vdpa, vf->nr_vring);
 	if (ret) {
 		IFCVF_ERR(pdev, "Failed to register to vDPA bus");
 		goto err;
-- 
cgit v1.2.3


From 90d1936681bc469824c6dfeda701efc884d3b448 Mon Sep 17 00:00:00 2001
From: Zhu Lingshan <lingshan.zhu@intel.com>
Date: Wed, 18 Aug 2021 17:57:14 +0800
Subject: vDPA/ifcvf: enable multiqueue and control vq

This commit enbales multi-queue and control vq
features for ifcvf

Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
Link: https://lore.kernel.org/r/20210818095714.3220-3-lingshan.zhu@intel.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
---
 drivers/vdpa/ifcvf/ifcvf_base.h |  9 ---------
 drivers/vdpa/ifcvf/ifcvf_main.c | 11 +++--------
 2 files changed, 3 insertions(+), 17 deletions(-)

(limited to 'drivers/vdpa')

diff --git a/drivers/vdpa/ifcvf/ifcvf_base.h b/drivers/vdpa/ifcvf/ifcvf_base.h
index 97d9019a3ec0..09918af3ecf8 100644
--- a/drivers/vdpa/ifcvf/ifcvf_base.h
+++ b/drivers/vdpa/ifcvf/ifcvf_base.h
@@ -22,15 +22,6 @@
 #define N3000_DEVICE_ID		0x1041
 #define N3000_SUBSYS_DEVICE_ID	0x001A
 
-#define IFCVF_NET_SUPPORTED_FEATURES \
-		((1ULL << VIRTIO_NET_F_MAC)			| \
-		 (1ULL << VIRTIO_F_ANY_LAYOUT)			| \
-		 (1ULL << VIRTIO_F_VERSION_1)			| \
-		 (1ULL << VIRTIO_NET_F_STATUS)			| \
-		 (1ULL << VIRTIO_F_ORDER_PLATFORM)		| \
-		 (1ULL << VIRTIO_F_ACCESS_PLATFORM)		| \
-		 (1ULL << VIRTIO_NET_F_MRG_RXBUF))
-
 /* Max 8 data queue pairs(16 queues) and one control vq for now. */
 #define IFCVF_MAX_QUEUES	17
 
diff --git a/drivers/vdpa/ifcvf/ifcvf_main.c b/drivers/vdpa/ifcvf/ifcvf_main.c
index 37675c93b1ff..bfc3d7d40c09 100644
--- a/drivers/vdpa/ifcvf/ifcvf_main.c
+++ b/drivers/vdpa/ifcvf/ifcvf_main.c
@@ -174,17 +174,12 @@ static u64 ifcvf_vdpa_get_features(struct vdpa_device *vdpa_dev)
 	struct ifcvf_adapter *adapter = vdpa_to_adapter(vdpa_dev);
 	struct ifcvf_hw *vf = vdpa_to_vf(vdpa_dev);
 	struct pci_dev *pdev = adapter->pdev;
-
+	u32 type = vf->dev_type;
 	u64 features;
 
-	switch (vf->dev_type) {
-	case VIRTIO_ID_NET:
-		features = ifcvf_get_features(vf) & IFCVF_NET_SUPPORTED_FEATURES;
-		break;
-	case VIRTIO_ID_BLOCK:
+	if (type == VIRTIO_ID_NET || type == VIRTIO_ID_BLOCK)
 		features = ifcvf_get_features(vf);
-		break;
-	default:
+	else {
 		features = 0;
 		IFCVF_ERR(pdev, "VIRTIO ID %u not supported\n", vf->dev_type);
 	}
-- 
cgit v1.2.3


From 4e57a9f622ccacacceadcead7bb65fb807383ab3 Mon Sep 17 00:00:00 2001
From: Eli Cohen <elic@nvidia.com>
Date: Mon, 23 Aug 2021 08:21:18 +0300
Subject: vdpa/mlx5: Remove redundant header file inclusion

linux/if_vlan.h is not required.
Remove it.

Signed-off-by: Eli Cohen <elic@nvidia.com>
Link: https://lore.kernel.org/r/20210823052123.14909-2-elic@nvidia.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
 drivers/vdpa/mlx5/core/mlx5_vdpa.h | 1 -
 1 file changed, 1 deletion(-)

(limited to 'drivers/vdpa')

diff --git a/drivers/vdpa/mlx5/core/mlx5_vdpa.h b/drivers/vdpa/mlx5/core/mlx5_vdpa.h
index 0002b2136b48..8d0a6f2cb3f0 100644
--- a/drivers/vdpa/mlx5/core/mlx5_vdpa.h
+++ b/drivers/vdpa/mlx5/core/mlx5_vdpa.h
@@ -5,7 +5,6 @@
 #define __MLX5_VDPA_H__
 
 #include <linux/etherdevice.h>
-#include <linux/if_vlan.h>
 #include <linux/vdpa.h>
 #include <linux/mlx5/driver.h>
 
-- 
cgit v1.2.3


From ae0428debf7cddf0863a95e415a1957d53384e7e Mon Sep 17 00:00:00 2001
From: Eli Cohen <elic@nvidia.com>
Date: Mon, 23 Aug 2021 08:21:19 +0300
Subject: vdpa/mlx5: function prototype modifications in preparation to control
 VQ

Use struct mlx5_vdpa_dev as an argument to setup_driver() and a few
others in preparation to control virtqueue support in a subsequent
patch. The control virtqueue is part of struct mlx5_vdpa_dev so this is
required.

Signed-off-by: Eli Cohen <elic@nvidia.com>
Link: https://lore.kernel.org/r/20210823052123.14909-3-elic@nvidia.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
 drivers/vdpa/mlx5/net/mlx5_vnet.c | 40 ++++++++++++++++++++-------------------
 1 file changed, 21 insertions(+), 19 deletions(-)

(limited to 'drivers/vdpa')

diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c
index 3cc12fcab08d..245c859ca5ae 100644
--- a/drivers/vdpa/mlx5/net/mlx5_vnet.c
+++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c
@@ -155,7 +155,7 @@ struct mlx5_vdpa_net {
 
 static void free_resources(struct mlx5_vdpa_net *ndev);
 static void init_mvqs(struct mlx5_vdpa_net *ndev);
-static int setup_driver(struct mlx5_vdpa_net *ndev);
+static int setup_driver(struct mlx5_vdpa_dev *mvdev);
 static void teardown_driver(struct mlx5_vdpa_net *ndev);
 
 static bool mlx5_vdpa_debug;
@@ -1507,12 +1507,13 @@ static int verify_min_features(struct mlx5_vdpa_dev *mvdev, u64 features)
 	return 0;
 }
 
-static int setup_virtqueues(struct mlx5_vdpa_net *ndev)
+static int setup_virtqueues(struct mlx5_vdpa_dev *mvdev)
 {
+	struct mlx5_vdpa_net *ndev = to_mlx5_vdpa_ndev(mvdev);
 	int err;
 	int i;
 
-	for (i = 0; i < 2 * mlx5_vdpa_max_qps(ndev->mvdev.max_vqs); i++) {
+	for (i = 0; i < 2 * mlx5_vdpa_max_qps(mvdev->max_vqs); i++) {
 		err = setup_vq(ndev, &ndev->vqs[i]);
 		if (err)
 			goto err_vq;
@@ -1671,8 +1672,9 @@ static void restore_channels_info(struct mlx5_vdpa_net *ndev)
 	}
 }
 
-static int mlx5_vdpa_change_map(struct mlx5_vdpa_net *ndev, struct vhost_iotlb *iotlb)
+static int mlx5_vdpa_change_map(struct mlx5_vdpa_dev *mvdev, struct vhost_iotlb *iotlb)
 {
+	struct mlx5_vdpa_net *ndev = to_mlx5_vdpa_ndev(mvdev);
 	int err;
 
 	suspend_vqs(ndev);
@@ -1681,58 +1683,59 @@ static int mlx5_vdpa_change_map(struct mlx5_vdpa_net *ndev, struct vhost_iotlb *
 		goto err_mr;
 
 	teardown_driver(ndev);
-	mlx5_vdpa_destroy_mr(&ndev->mvdev);
-	err = mlx5_vdpa_create_mr(&ndev->mvdev, iotlb);
+	mlx5_vdpa_destroy_mr(mvdev);
+	err = mlx5_vdpa_create_mr(mvdev, iotlb);
 	if (err)
 		goto err_mr;
 
-	if (!(ndev->mvdev.status & VIRTIO_CONFIG_S_DRIVER_OK))
+	if (!(mvdev->status & VIRTIO_CONFIG_S_DRIVER_OK))
 		return 0;
 
 	restore_channels_info(ndev);
-	err = setup_driver(ndev);
+	err = setup_driver(mvdev);
 	if (err)
 		goto err_setup;
 
 	return 0;
 
 err_setup:
-	mlx5_vdpa_destroy_mr(&ndev->mvdev);
+	mlx5_vdpa_destroy_mr(mvdev);
 err_mr:
 	return err;
 }
 
-static int setup_driver(struct mlx5_vdpa_net *ndev)
+static int setup_driver(struct mlx5_vdpa_dev *mvdev)
 {
+	struct mlx5_vdpa_net *ndev = to_mlx5_vdpa_ndev(mvdev);
 	int err;
 
 	mutex_lock(&ndev->reslock);
 	if (ndev->setup) {
-		mlx5_vdpa_warn(&ndev->mvdev, "setup driver called for already setup driver\n");
+		mlx5_vdpa_warn(mvdev, "setup driver called for already setup driver\n");
 		err = 0;
 		goto out;
 	}
-	err = setup_virtqueues(ndev);
+	err = setup_virtqueues(mvdev);
 	if (err) {
-		mlx5_vdpa_warn(&ndev->mvdev, "setup_virtqueues\n");
+		mlx5_vdpa_warn(mvdev, "setup_virtqueues\n");
 		goto out;
 	}
 
 	err = create_rqt(ndev);
 	if (err) {
-		mlx5_vdpa_warn(&ndev->mvdev, "create_rqt\n");
+		mlx5_vdpa_warn(mvdev, "create_rqt\n");
 		goto err_rqt;
 	}
 
 	err = create_tir(ndev);
 	if (err) {
-		mlx5_vdpa_warn(&ndev->mvdev, "create_tir\n");
+		mlx5_vdpa_warn(mvdev, "create_tir\n");
 		goto err_tir;
 	}
 
 	err = add_fwd_to_tir(ndev);
 	if (err) {
-		mlx5_vdpa_warn(&ndev->mvdev, "add_fwd_to_tir\n");
+		mlx5_vdpa_warn(mvdev, "add_fwd_to_tir\n");
 		goto err_fwd;
 	}
 	ndev->setup = true;
@@ -1798,7 +1801,7 @@ static void mlx5_vdpa_set_status(struct vdpa_device *vdev, u8 status)
 
 	if ((status ^ ndev->mvdev.status) & VIRTIO_CONFIG_S_DRIVER_OK) {
 		if (status & VIRTIO_CONFIG_S_DRIVER_OK) {
-			err = setup_driver(ndev);
+			err = setup_driver(mvdev);
 			if (err) {
 				mlx5_vdpa_warn(mvdev, "failed to setup driver\n");
 				goto err_setup;
@@ -1848,7 +1851,6 @@ static u32 mlx5_vdpa_get_generation(struct vdpa_device *vdev)
 static int mlx5_vdpa_set_map(struct vdpa_device *vdev, struct vhost_iotlb *iotlb)
 {
 	struct mlx5_vdpa_dev *mvdev = to_mvdev(vdev);
-	struct mlx5_vdpa_net *ndev = to_mlx5_vdpa_ndev(mvdev);
 	bool change_map;
 	int err;
 
@@ -1859,7 +1861,7 @@ static int mlx5_vdpa_set_map(struct vdpa_device *vdev, struct vhost_iotlb *iotlb
 	}
 
 	if (change_map)
-		return mlx5_vdpa_change_map(ndev, iotlb);
+		return mlx5_vdpa_change_map(mvdev, iotlb);
 
 	return 0;
 }
-- 
cgit v1.2.3


From db296d252dfb977885391e47d3fb6ac5a1f9601c Mon Sep 17 00:00:00 2001
From: Eli Cohen <elic@nvidia.com>
Date: Mon, 23 Aug 2021 08:21:20 +0300
Subject: vdpa/mlx5: Decouple virtqueue callback from struct
 mlx5_vdpa_virtqueue

Instead, define an array of struct vdpa_callback on struct mlx5_vdpa_net
and use it to store callbacks for any virtqueue provided. This is
required due to the fact that callback configurations arrive before feature
negotiation. With control VQ and multiqueue introduced next we want to
save the information until after feature negotiation where we know the
CVQ index.

Signed-off-by: Eli Cohen <elic@nvidia.com>
Link: https://lore.kernel.org/r/20210823052123.14909-4-elic@nvidia.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
 drivers/vdpa/mlx5/net/mlx5_vnet.c | 17 +++++++++--------
 1 file changed, 9 insertions(+), 8 deletions(-)

(limited to 'drivers/vdpa')

diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c
index 245c859ca5ae..3ae2e5ae2be1 100644
--- a/drivers/vdpa/mlx5/net/mlx5_vnet.c
+++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c
@@ -90,7 +90,6 @@ struct mlx5_vq_restore_info {
 	u16 avail_index;
 	u16 used_index;
 	bool ready;
-	struct vdpa_callback cb;
 	bool restore;
 };
 
@@ -100,7 +99,6 @@ struct mlx5_vdpa_virtqueue {
 	u64 device_addr;
 	u64 driver_addr;
 	u32 num_ent;
-	struct vdpa_callback event_cb;
 
 	/* Resources for implementing the notification channel from the device
 	 * to the driver. fwqp is the firmware end of an RC connection; the
@@ -140,6 +138,7 @@ struct mlx5_vdpa_net {
 	struct mlx5_vdpa_net_resources res;
 	struct virtio_net_config config;
 	struct mlx5_vdpa_virtqueue vqs[MLX5_MAX_SUPPORTED_VQS];
+	struct vdpa_callback event_cbs[MLX5_MAX_SUPPORTED_VQS + 1];
 
 	/* Serialize vq resources creation and destruction. This is required
 	 * since memory map might change and we need to destroy and create
@@ -481,6 +480,10 @@ static int mlx5_vdpa_poll_one(struct mlx5_vdpa_cq *vcq)
 
 static void mlx5_vdpa_handle_completions(struct mlx5_vdpa_virtqueue *mvq, int num)
 {
+	struct mlx5_vdpa_net *ndev = mvq->ndev;
+	struct vdpa_callback *event_cb;
+
+	event_cb = &ndev->event_cbs[mvq->index];
 	mlx5_cq_set_ci(&mvq->cq.mcq);
 
 	/* make sure CQ cosumer update is visible to the hardware before updating
@@ -488,8 +491,8 @@ static void mlx5_vdpa_handle_completions(struct mlx5_vdpa_virtqueue *mvq, int nu
 	 */
 	dma_wmb();
 	rx_post(&mvq->vqqp, num);
-	if (mvq->event_cb.callback)
-		mvq->event_cb.callback(mvq->event_cb.private);
+	if (event_cb->callback)
+		event_cb->callback(event_cb->private);
 }
 
 static void mlx5_vdpa_cq_comp(struct mlx5_core_cq *mcq, struct mlx5_eqe *eqe)
@@ -1384,9 +1387,8 @@ static void mlx5_vdpa_set_vq_cb(struct vdpa_device *vdev, u16 idx, struct vdpa_c
 {
 	struct mlx5_vdpa_dev *mvdev = to_mvdev(vdev);
 	struct mlx5_vdpa_net *ndev = to_mlx5_vdpa_ndev(mvdev);
-	struct mlx5_vdpa_virtqueue *vq = &ndev->vqs[idx];
 
-	vq->event_cb = *cb;
+	ndev->event_cbs[idx] = *cb;
 }
 
 static void mlx5_vdpa_set_vq_ready(struct vdpa_device *vdev, u16 idx, bool ready)
@@ -1623,7 +1625,6 @@ static int save_channel_info(struct mlx5_vdpa_net *ndev, struct mlx5_vdpa_virtqu
 	ri->desc_addr = mvq->desc_addr;
 	ri->device_addr = mvq->device_addr;
 	ri->driver_addr = mvq->driver_addr;
-	ri->cb = mvq->event_cb;
 	ri->restore = true;
 	return 0;
 }
@@ -1668,7 +1669,6 @@ static void restore_channels_info(struct mlx5_vdpa_net *ndev)
 		mvq->desc_addr = ri->desc_addr;
 		mvq->device_addr = ri->device_addr;
 		mvq->driver_addr = ri->driver_addr;
-		mvq->event_cb = ri->cb;
 	}
 }
 
@@ -1791,6 +1791,7 @@ static void mlx5_vdpa_set_status(struct vdpa_device *vdev, u8 status)
 		mlx5_vdpa_destroy_mr(&ndev->mvdev);
 		ndev->mvdev.status = 0;
 		ndev->mvdev.mlx_features = 0;
+		memset(ndev->event_cbs, 0, sizeof(ndev->event_cbs));
 		++mvdev->generation;
 		if (MLX5_CAP_GEN(mvdev->mdev, umem_uid_0)) {
 			if (mlx5_vdpa_create_mr(mvdev, NULL))
-- 
cgit v1.2.3


From e4fc66508c884b87422a98259cdfe135edae130f Mon Sep 17 00:00:00 2001
From: Eli Cohen <elic@nvidia.com>
Date: Mon, 23 Aug 2021 08:21:21 +0300
Subject: vdpa/mlx5: Ensure valid indices are provided

Following patches add control virtuqeue and multiqueue support. We want
to verify that the index value to callbacks referencing a virtqueue is
valid.

The logic defining valid indices is as follows:
CVQ clear: 0 and 1.
CVQ set, MQ clear: 0, 1 and 2
CVQ set, MQ set: 0..nvq where nvq is whatever provided to
_vdpa_register_device()

Signed-off-by: Eli Cohen <elic@nvidia.com>
Link: https://lore.kernel.org/r/20210823052123.14909-5-elic@nvidia.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
 drivers/vdpa/mlx5/core/mlx5_vdpa.h |  1 +
 drivers/vdpa/mlx5/net/mlx5_vnet.c  | 54 ++++++++++++++++++++++++++++++++++++++
 2 files changed, 55 insertions(+)

(limited to 'drivers/vdpa')

diff --git a/drivers/vdpa/mlx5/core/mlx5_vdpa.h b/drivers/vdpa/mlx5/core/mlx5_vdpa.h
index 8d0a6f2cb3f0..41b20855ed31 100644
--- a/drivers/vdpa/mlx5/core/mlx5_vdpa.h
+++ b/drivers/vdpa/mlx5/core/mlx5_vdpa.h
@@ -56,6 +56,7 @@ struct mlx5_vdpa_dev {
 	u64 actual_features;
 	u8 status;
 	u32 max_vqs;
+	u16 max_idx;
 	u32 generation;
 
 	struct mlx5_vdpa_mr mr;
diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c
index 3ae2e5ae2be1..eafad2a19299 100644
--- a/drivers/vdpa/mlx5/net/mlx5_vnet.c
+++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c
@@ -45,6 +45,8 @@ MODULE_LICENSE("Dual BSD/GPL");
 	(VIRTIO_CONFIG_S_ACKNOWLEDGE | VIRTIO_CONFIG_S_DRIVER | VIRTIO_CONFIG_S_DRIVER_OK |        \
 	 VIRTIO_CONFIG_S_FEATURES_OK | VIRTIO_CONFIG_S_NEEDS_RESET | VIRTIO_CONFIG_S_FAILED)
 
+#define MLX5_FEATURE(_mvdev, _feature) (!!((_mvdev)->actual_features & BIT_ULL(_feature)))
+
 struct mlx5_vdpa_net_resources {
 	u32 tisn;
 	u32 tdn;
@@ -133,6 +135,14 @@ struct mlx5_vdpa_virtqueue {
  */
 #define MLX5_MAX_SUPPORTED_VQS 16
 
+static bool is_index_valid(struct mlx5_vdpa_dev *mvdev, u16 idx)
+{
+	if (unlikely(idx > mvdev->max_idx))
+		return false;
+
+	return true;
+}
+
 struct mlx5_vdpa_net {
 	struct mlx5_vdpa_dev mvdev;
 	struct mlx5_vdpa_net_resources res;
@@ -1354,6 +1364,9 @@ static void mlx5_vdpa_kick_vq(struct vdpa_device *vdev, u16 idx)
 	struct mlx5_vdpa_net *ndev = to_mlx5_vdpa_ndev(mvdev);
 	struct mlx5_vdpa_virtqueue *mvq = &ndev->vqs[idx];
 
+	if (!is_index_valid(mvdev, idx))
+		return;
+
 	if (unlikely(!mvq->ready))
 		return;
 
@@ -1367,6 +1380,9 @@ static int mlx5_vdpa_set_vq_address(struct vdpa_device *vdev, u16 idx, u64 desc_
 	struct mlx5_vdpa_net *ndev = to_mlx5_vdpa_ndev(mvdev);
 	struct mlx5_vdpa_virtqueue *mvq = &ndev->vqs[idx];
 
+	if (!is_index_valid(mvdev, idx))
+		return -EINVAL;
+
 	mvq->desc_addr = desc_area;
 	mvq->device_addr = device_area;
 	mvq->driver_addr = driver_area;
@@ -1379,6 +1395,9 @@ static void mlx5_vdpa_set_vq_num(struct vdpa_device *vdev, u16 idx, u32 num)
 	struct mlx5_vdpa_net *ndev = to_mlx5_vdpa_ndev(mvdev);
 	struct mlx5_vdpa_virtqueue *mvq;
 
+	if (!is_index_valid(mvdev, idx))
+		return;
+
 	mvq = &ndev->vqs[idx];
 	mvq->num_ent = num;
 }
@@ -1397,6 +1416,9 @@ static void mlx5_vdpa_set_vq_ready(struct vdpa_device *vdev, u16 idx, bool ready
 	struct mlx5_vdpa_net *ndev = to_mlx5_vdpa_ndev(mvdev);
 	struct mlx5_vdpa_virtqueue *mvq = &ndev->vqs[idx];
 
+	if (!is_index_valid(mvdev, idx))
+		return;
+
 	if (!ready)
 		suspend_vq(ndev, mvq);
 
@@ -1409,6 +1431,9 @@ static bool mlx5_vdpa_get_vq_ready(struct vdpa_device *vdev, u16 idx)
 	struct mlx5_vdpa_net *ndev = to_mlx5_vdpa_ndev(mvdev);
 	struct mlx5_vdpa_virtqueue *mvq = &ndev->vqs[idx];
 
+	if (!is_index_valid(mvdev, idx))
+		return false;
+
 	return mvq->ready;
 }
 
@@ -1419,6 +1444,9 @@ static int mlx5_vdpa_set_vq_state(struct vdpa_device *vdev, u16 idx,
 	struct mlx5_vdpa_net *ndev = to_mlx5_vdpa_ndev(mvdev);
 	struct mlx5_vdpa_virtqueue *mvq = &ndev->vqs[idx];
 
+	if (!is_index_valid(mvdev, idx))
+		return -EINVAL;
+
 	if (mvq->fw_state == MLX5_VIRTIO_NET_Q_OBJECT_STATE_RDY) {
 		mlx5_vdpa_warn(mvdev, "can't modify available index\n");
 		return -EINVAL;
@@ -1437,6 +1465,9 @@ static int mlx5_vdpa_get_vq_state(struct vdpa_device *vdev, u16 idx, struct vdpa
 	struct mlx5_virtq_attr attr;
 	int err;
 
+	if (!is_index_valid(mvdev, idx))
+		return -EINVAL;
+
 	/* If the virtq object was destroyed, use the value saved at
 	 * the last minute of suspend_vq. This caters for userspace
 	 * that cares about emulating the index after vq is stopped.
@@ -1556,6 +1587,24 @@ static __virtio16 cpu_to_mlx5vdpa16(struct mlx5_vdpa_dev *mvdev, u16 val)
 	return __cpu_to_virtio16(mlx5_vdpa_is_little_endian(mvdev), val);
 }
 
+static void update_cvq_info(struct mlx5_vdpa_dev *mvdev)
+{
+	if (MLX5_FEATURE(mvdev, VIRTIO_NET_F_CTRL_VQ)) {
+		if (MLX5_FEATURE(mvdev, VIRTIO_NET_F_MQ)) {
+			/* MQ supported. CVQ index is right above the last data virtqueue's */
+			mvdev->max_idx = mvdev->max_vqs;
+		} else {
+			/* Only CVQ supportted. data virtqueues occupy indices 0 and 1.
+			 * CVQ gets index 2
+			 */
+			mvdev->max_idx = 2;
+		}
+	} else {
+		/* Two data virtqueues only: one for rx and one for tx */
+		mvdev->max_idx = 1;
+	}
+}
+
 static int mlx5_vdpa_set_features(struct vdpa_device *vdev, u64 features)
 {
 	struct mlx5_vdpa_dev *mvdev = to_mvdev(vdev);
@@ -1571,6 +1620,7 @@ static int mlx5_vdpa_set_features(struct vdpa_device *vdev, u64 features)
 	ndev->mvdev.actual_features = features & ndev->mvdev.mlx_features;
 	ndev->config.mtu = cpu_to_mlx5vdpa16(mvdev, ndev->mtu);
 	ndev->config.status |= cpu_to_mlx5vdpa16(mvdev, VIRTIO_NET_S_LINK_UP);
+	update_cvq_info(mvdev);
 	return err;
 }
 
@@ -1792,6 +1842,7 @@ static void mlx5_vdpa_set_status(struct vdpa_device *vdev, u8 status)
 		ndev->mvdev.status = 0;
 		ndev->mvdev.mlx_features = 0;
 		memset(ndev->event_cbs, 0, sizeof(ndev->event_cbs));
+		ndev->mvdev.actual_features = 0;
 		++mvdev->generation;
 		if (MLX5_CAP_GEN(mvdev->mdev, umem_uid_0)) {
 			if (mlx5_vdpa_create_mr(mvdev, NULL))
@@ -1892,6 +1943,9 @@ static struct vdpa_notification_area mlx5_get_vq_notification(struct vdpa_device
 	struct mlx5_vdpa_net *ndev;
 	phys_addr_t addr;
 
+	if (!is_index_valid(mvdev, idx))
+		return ret;
+
 	/* If SF BAR size is smaller than PAGE_SIZE, do not use direct
 	 * notification to avoid the risk of mapping pages that contain BAR of more
 	 * than one SF
-- 
cgit v1.2.3


From 5262912ef3cfc5e518892c3d67fb36412cb813e2 Mon Sep 17 00:00:00 2001
From: Eli Cohen <elic@nvidia.com>
Date: Mon, 23 Aug 2021 08:21:22 +0300
Subject: vdpa/mlx5: Add support for control VQ and MAC setting

Add support to handle control virtqueue configurations per virtio
specification. The control virtqueue is implemented in software and no
hardware offloading is involved.

Control VQ configuration need task context, therefore all configurations
are handled in a workqueue created for the purpose.

Modifications are made to the memory registration code to allow for
saving a copy of itolb to be used by the control VQ to access the vring.

The max number of data virtqueus supported by the driver has been
updated to 2 since multiqueue is not supported at this stage and we need
to ensure consistency of VQ indices mapping to either data or control
VQ.

Signed-off-by: Eli Cohen <elic@nvidia.com>
Link: https://lore.kernel.org/r/20210823052123.14909-6-elic@nvidia.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
 drivers/vdpa/Kconfig               |   1 +
 drivers/vdpa/mlx5/core/mlx5_vdpa.h |  23 ++++
 drivers/vdpa/mlx5/core/mr.c        |  81 +++++++++----
 drivers/vdpa/mlx5/core/resources.c |  25 ++++
 drivers/vdpa/mlx5/net/mlx5_vnet.c  | 231 +++++++++++++++++++++++++++++++++++--
 5 files changed, 329 insertions(+), 32 deletions(-)

(limited to 'drivers/vdpa')

diff --git a/drivers/vdpa/Kconfig b/drivers/vdpa/Kconfig
index a503c1b2bfd9..e48e2b10ca36 100644
--- a/drivers/vdpa/Kconfig
+++ b/drivers/vdpa/Kconfig
@@ -53,6 +53,7 @@ config MLX5_VDPA
 config MLX5_VDPA_NET
 	tristate "vDPA driver for ConnectX devices"
 	select MLX5_VDPA
+	select VHOST_RING
 	depends on MLX5_CORE
 	help
 	  VDPA network driver for ConnectX6 and newer. Provides offloading
diff --git a/drivers/vdpa/mlx5/core/mlx5_vdpa.h b/drivers/vdpa/mlx5/core/mlx5_vdpa.h
index 41b20855ed31..6c43476a69cb 100644
--- a/drivers/vdpa/mlx5/core/mlx5_vdpa.h
+++ b/drivers/vdpa/mlx5/core/mlx5_vdpa.h
@@ -5,6 +5,7 @@
 #define __MLX5_VDPA_H__
 
 #include <linux/etherdevice.h>
+#include <linux/vringh.h>
 #include <linux/vdpa.h>
 #include <linux/mlx5/driver.h>
 
@@ -47,6 +48,26 @@ struct mlx5_vdpa_resources {
 	bool valid;
 };
 
+struct mlx5_control_vq {
+	struct vhost_iotlb *iotlb;
+	/* spinlock to synchronize iommu table */
+	spinlock_t iommu_lock;
+	struct vringh vring;
+	bool ready;
+	u64 desc_addr;
+	u64 device_addr;
+	u64 driver_addr;
+	struct vdpa_callback event_cb;
+	struct vringh_kiov riov;
+	struct vringh_kiov wiov;
+	unsigned short head;
+};
+
+struct mlx5_ctrl_wq_ent {
+	struct work_struct work;
+	struct mlx5_vdpa_dev *mvdev;
+};
+
 struct mlx5_vdpa_dev {
 	struct vdpa_device vdev;
 	struct mlx5_core_dev *mdev;
@@ -60,6 +81,8 @@ struct mlx5_vdpa_dev {
 	u32 generation;
 
 	struct mlx5_vdpa_mr mr;
+	struct mlx5_control_vq cvq;
+	struct workqueue_struct *wq;
 };
 
 int mlx5_vdpa_alloc_pd(struct mlx5_vdpa_dev *dev, u32 *pdn, u16 uid);
diff --git a/drivers/vdpa/mlx5/core/mr.c b/drivers/vdpa/mlx5/core/mr.c
index e59135fa867e..ff010c6d0cd3 100644
--- a/drivers/vdpa/mlx5/core/mr.c
+++ b/drivers/vdpa/mlx5/core/mr.c
@@ -1,6 +1,7 @@
 // SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
 /* Copyright (c) 2020 Mellanox Technologies Ltd. */
 
+#include <linux/vhost_types.h>
 #include <linux/vdpa.h>
 #include <linux/gcd.h>
 #include <linux/string.h>
@@ -451,33 +452,30 @@ static void destroy_dma_mr(struct mlx5_vdpa_dev *mvdev, struct mlx5_vdpa_mr *mr)
 	mlx5_vdpa_destroy_mkey(mvdev, &mr->mkey);
 }
 
-static int _mlx5_vdpa_create_mr(struct mlx5_vdpa_dev *mvdev, struct vhost_iotlb *iotlb)
+static int dup_iotlb(struct mlx5_vdpa_dev *mvdev, struct vhost_iotlb *src)
 {
-	struct mlx5_vdpa_mr *mr = &mvdev->mr;
+	struct vhost_iotlb_map *map;
+	u64 start = 0, last = ULLONG_MAX;
 	int err;
 
-	if (mr->initialized)
-		return 0;
-
-	if (iotlb)
-		err = create_user_mr(mvdev, iotlb);
-	else
-		err = create_dma_mr(mvdev, mr);
-
-	if (!err)
-		mr->initialized = true;
+	if (!src) {
+		err = vhost_iotlb_add_range(mvdev->cvq.iotlb, start, last, start, VHOST_ACCESS_RW);
+		return err;
+	}
 
-	return err;
+	for (map = vhost_iotlb_itree_first(src, start, last); map;
+		map = vhost_iotlb_itree_next(map, start, last)) {
+		err = vhost_iotlb_add_range(mvdev->cvq.iotlb, map->start, map->last,
+					    map->addr, map->perm);
+		if (err)
+			return err;
+	}
+	return 0;
 }
 
-int mlx5_vdpa_create_mr(struct mlx5_vdpa_dev *mvdev, struct vhost_iotlb *iotlb)
+static void prune_iotlb(struct mlx5_vdpa_dev *mvdev)
 {
-	int err;
-
-	mutex_lock(&mvdev->mr.mkey_mtx);
-	err = _mlx5_vdpa_create_mr(mvdev, iotlb);
-	mutex_unlock(&mvdev->mr.mkey_mtx);
-	return err;
+	vhost_iotlb_del_range(mvdev->cvq.iotlb, 0, ULLONG_MAX);
 }
 
 static void destroy_user_mr(struct mlx5_vdpa_dev *mvdev, struct mlx5_vdpa_mr *mr)
@@ -501,6 +499,7 @@ void mlx5_vdpa_destroy_mr(struct mlx5_vdpa_dev *mvdev)
 	if (!mr->initialized)
 		goto out;
 
+	prune_iotlb(mvdev);
 	if (mr->user_mr)
 		destroy_user_mr(mvdev, mr);
 	else
@@ -512,6 +511,48 @@ out:
 	mutex_unlock(&mr->mkey_mtx);
 }
 
+static int _mlx5_vdpa_create_mr(struct mlx5_vdpa_dev *mvdev, struct vhost_iotlb *iotlb)
+{
+	struct mlx5_vdpa_mr *mr = &mvdev->mr;
+	int err;
+
+	if (mr->initialized)
+		return 0;
+
+	if (iotlb)
+		err = create_user_mr(mvdev, iotlb);
+	else
+		err = create_dma_mr(mvdev, mr);
+
+	if (err)
+		return err;
+
+	err = dup_iotlb(mvdev, iotlb);
+	if (err)
+		goto out_err;
+
+	mr->initialized = true;
+	return 0;
+
+out_err:
+	if (iotlb)
+		destroy_user_mr(mvdev, mr);
+	else
+		destroy_dma_mr(mvdev, mr);
+
+	return err;
+}
+
+int mlx5_vdpa_create_mr(struct mlx5_vdpa_dev *mvdev, struct vhost_iotlb *iotlb)
+{
+	int err;
+
+	mutex_lock(&mvdev->mr.mkey_mtx);
+	err = _mlx5_vdpa_create_mr(mvdev, iotlb);
+	mutex_unlock(&mvdev->mr.mkey_mtx);
+	return err;
+}
+
 int mlx5_vdpa_handle_set_map(struct mlx5_vdpa_dev *mvdev, struct vhost_iotlb *iotlb,
 			     bool *change_map)
 {
diff --git a/drivers/vdpa/mlx5/core/resources.c b/drivers/vdpa/mlx5/core/resources.c
index d4606213f88a..b3c08dfa98e8 100644
--- a/drivers/vdpa/mlx5/core/resources.c
+++ b/drivers/vdpa/mlx5/core/resources.c
@@ -1,6 +1,7 @@
 // SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
 /* Copyright (c) 2020 Mellanox Technologies Ltd. */
 
+#include <linux/iova.h>
 #include <linux/mlx5/driver.h>
 #include "mlx5_vdpa.h"
 
@@ -221,6 +222,22 @@ int mlx5_vdpa_destroy_mkey(struct mlx5_vdpa_dev *mvdev, struct mlx5_core_mkey *m
 	return mlx5_cmd_exec_in(mvdev->mdev, destroy_mkey, in);
 }
 
+static int init_ctrl_vq(struct mlx5_vdpa_dev *mvdev)
+{
+	mvdev->cvq.iotlb = vhost_iotlb_alloc(0, 0);
+	if (!mvdev->cvq.iotlb)
+		return -ENOMEM;
+
+	vringh_set_iotlb(&mvdev->cvq.vring, mvdev->cvq.iotlb, &mvdev->cvq.iommu_lock);
+
+	return 0;
+}
+
+static void cleanup_ctrl_vq(struct mlx5_vdpa_dev *mvdev)
+{
+	vhost_iotlb_free(mvdev->cvq.iotlb);
+}
+
 int mlx5_vdpa_alloc_resources(struct mlx5_vdpa_dev *mvdev)
 {
 	u64 offset = MLX5_CAP64_DEV_VDPA_EMULATION(mvdev->mdev, doorbell_bar_offset);
@@ -260,10 +277,17 @@ int mlx5_vdpa_alloc_resources(struct mlx5_vdpa_dev *mvdev)
 		err = -ENOMEM;
 		goto err_key;
 	}
+
+	err = init_ctrl_vq(mvdev);
+	if (err)
+		goto err_ctrl;
+
 	res->valid = true;
 
 	return 0;
 
+err_ctrl:
+	iounmap(res->kick_addr);
 err_key:
 	dealloc_pd(mvdev, res->pdn, res->uid);
 err_pd:
@@ -282,6 +306,7 @@ void mlx5_vdpa_free_resources(struct mlx5_vdpa_dev *mvdev)
 	if (!res->valid)
 		return;
 
+	cleanup_ctrl_vq(mvdev);
 	iounmap(res->kick_addr);
 	res->kick_addr = NULL;
 	dealloc_pd(mvdev, res->pdn, res->uid);
diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c
index eafad2a19299..1b208aa656cb 100644
--- a/drivers/vdpa/mlx5/net/mlx5_vnet.c
+++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c
@@ -133,7 +133,7 @@ struct mlx5_vdpa_virtqueue {
 /* We will remove this limitation once mlx5_vdpa_alloc_resources()
  * provides for driver space allocation
  */
-#define MLX5_MAX_SUPPORTED_VQS 16
+#define MLX5_MAX_SUPPORTED_VQS 2
 
 static bool is_index_valid(struct mlx5_vdpa_dev *mvdev, u16 idx)
 {
@@ -160,6 +160,7 @@ struct mlx5_vdpa_net {
 	struct mlx5_flow_handle *rx_rule;
 	bool setup;
 	u16 mtu;
+	u32 cur_num_vqs;
 };
 
 static void free_resources(struct mlx5_vdpa_net *ndev);
@@ -169,6 +170,8 @@ static void teardown_driver(struct mlx5_vdpa_net *ndev);
 
 static bool mlx5_vdpa_debug;
 
+#define MLX5_CVQ_MAX_ENT 16
+
 #define MLX5_LOG_VIO_FLAG(_feature)                                                                \
 	do {                                                                                       \
 		if (features & BIT_ULL(_feature))                                                  \
@@ -186,6 +189,16 @@ static inline u32 mlx5_vdpa_max_qps(int max_vqs)
 	return max_vqs / 2;
 }
 
+static u16 ctrl_vq_idx(struct mlx5_vdpa_dev *mvdev)
+{
+	return 2 * mlx5_vdpa_max_qps(mvdev->max_vqs);
+}
+
+static bool is_ctrl_vq_idx(struct mlx5_vdpa_dev *mvdev, u16 idx)
+{
+	return idx == ctrl_vq_idx(mvdev);
+}
+
 static void print_status(struct mlx5_vdpa_dev *mvdev, u8 status, bool set)
 {
 	if (status & ~VALID_STATUS_MASK)
@@ -1358,15 +1371,132 @@ static void remove_fwd_to_tir(struct mlx5_vdpa_net *ndev)
 	ndev->rx_rule = NULL;
 }
 
+static virtio_net_ctrl_ack handle_ctrl_mac(struct mlx5_vdpa_dev *mvdev, u8 cmd)
+{
+	struct mlx5_vdpa_net *ndev = to_mlx5_vdpa_ndev(mvdev);
+	struct mlx5_control_vq *cvq = &mvdev->cvq;
+	virtio_net_ctrl_ack status = VIRTIO_NET_ERR;
+	struct mlx5_core_dev *pfmdev;
+	size_t read;
+	u8 mac[ETH_ALEN];
+
+	pfmdev = pci_get_drvdata(pci_physfn(mvdev->mdev->pdev));
+	switch (cmd) {
+	case VIRTIO_NET_CTRL_MAC_ADDR_SET:
+		read = vringh_iov_pull_iotlb(&cvq->vring, &cvq->riov, (void *)mac, ETH_ALEN);
+		if (read != ETH_ALEN)
+			break;
+
+		if (!memcmp(ndev->config.mac, mac, 6)) {
+			status = VIRTIO_NET_OK;
+			break;
+		}
+
+		if (!is_zero_ether_addr(ndev->config.mac)) {
+			if (mlx5_mpfs_del_mac(pfmdev, ndev->config.mac)) {
+				mlx5_vdpa_warn(mvdev, "failed to delete old MAC %pM from MPFS table\n",
+					       ndev->config.mac);
+				break;
+			}
+		}
+
+		if (mlx5_mpfs_add_mac(pfmdev, mac)) {
+			mlx5_vdpa_warn(mvdev, "failed to insert new MAC %pM into MPFS table\n",
+				       mac);
+			break;
+		}
+
+		memcpy(ndev->config.mac, mac, ETH_ALEN);
+		status = VIRTIO_NET_OK;
+		break;
+
+	default:
+		break;
+	}
+
+	return status;
+}
+
+static void mlx5_cvq_kick_handler(struct work_struct *work)
+{
+	virtio_net_ctrl_ack status = VIRTIO_NET_ERR;
+	struct virtio_net_ctrl_hdr ctrl;
+	struct mlx5_ctrl_wq_ent *wqent;
+	struct mlx5_vdpa_dev *mvdev;
+	struct mlx5_control_vq *cvq;
+	struct mlx5_vdpa_net *ndev;
+	size_t read, write;
+	int err;
+
+	wqent = container_of(work, struct mlx5_ctrl_wq_ent, work);
+	mvdev = wqent->mvdev;
+	ndev = to_mlx5_vdpa_ndev(mvdev);
+	cvq = &mvdev->cvq;
+	if (!(ndev->mvdev.actual_features & BIT_ULL(VIRTIO_NET_F_CTRL_VQ)))
+		goto out;
+
+	if (!cvq->ready)
+		goto out;
+
+	while (true) {
+		err = vringh_getdesc_iotlb(&cvq->vring, &cvq->riov, &cvq->wiov, &cvq->head,
+					   GFP_ATOMIC);
+		if (err <= 0)
+			break;
+
+		read = vringh_iov_pull_iotlb(&cvq->vring, &cvq->riov, &ctrl, sizeof(ctrl));
+		if (read != sizeof(ctrl))
+			break;
+
+		switch (ctrl.class) {
+		case VIRTIO_NET_CTRL_MAC:
+			status = handle_ctrl_mac(mvdev, ctrl.cmd);
+			break;
+
+		default:
+			break;
+		}
+
+		/* Make sure data is written before advancing index */
+		smp_wmb();
+
+		write = vringh_iov_push_iotlb(&cvq->vring, &cvq->wiov, &status, sizeof(status));
+		vringh_complete_iotlb(&cvq->vring, cvq->head, write);
+		vringh_kiov_cleanup(&cvq->riov);
+		vringh_kiov_cleanup(&cvq->wiov);
+
+		if (vringh_need_notify_iotlb(&cvq->vring))
+			vringh_notify(&cvq->vring);
+	}
+out:
+	kfree(wqent);
+}
+
 static void mlx5_vdpa_kick_vq(struct vdpa_device *vdev, u16 idx)
 {
 	struct mlx5_vdpa_dev *mvdev = to_mvdev(vdev);
 	struct mlx5_vdpa_net *ndev = to_mlx5_vdpa_ndev(mvdev);
-	struct mlx5_vdpa_virtqueue *mvq = &ndev->vqs[idx];
+	struct mlx5_vdpa_virtqueue *mvq;
+	struct mlx5_ctrl_wq_ent *wqent;
 
 	if (!is_index_valid(mvdev, idx))
 		return;
 
+	if (unlikely(is_ctrl_vq_idx(mvdev, idx))) {
+		if (!mvdev->cvq.ready)
+			return;
+
+		wqent = kzalloc(sizeof(*wqent), GFP_ATOMIC);
+		if (!wqent)
+			return;
+
+		wqent->mvdev = mvdev;
+		INIT_WORK(&wqent->work, mlx5_cvq_kick_handler);
+		queue_work(mvdev->wq, &wqent->work);
+		return;
+	}
+
+	mvq = &ndev->vqs[idx];
 	if (unlikely(!mvq->ready))
 		return;
 
@@ -1378,11 +1508,19 @@ static int mlx5_vdpa_set_vq_address(struct vdpa_device *vdev, u16 idx, u64 desc_
 {
 	struct mlx5_vdpa_dev *mvdev = to_mvdev(vdev);
 	struct mlx5_vdpa_net *ndev = to_mlx5_vdpa_ndev(mvdev);
-	struct mlx5_vdpa_virtqueue *mvq = &ndev->vqs[idx];
+	struct mlx5_vdpa_virtqueue *mvq;
 
 	if (!is_index_valid(mvdev, idx))
 		return -EINVAL;
 
+	if (is_ctrl_vq_idx(mvdev, idx)) {
+		mvdev->cvq.desc_addr = desc_area;
+		mvdev->cvq.device_addr = device_area;
+		mvdev->cvq.driver_addr = driver_area;
+		return 0;
+	}
+
+	mvq = &ndev->vqs[idx];
 	mvq->desc_addr = desc_area;
 	mvq->device_addr = device_area;
 	mvq->driver_addr = driver_area;
@@ -1395,7 +1533,7 @@ static void mlx5_vdpa_set_vq_num(struct vdpa_device *vdev, u16 idx, u32 num)
 	struct mlx5_vdpa_net *ndev = to_mlx5_vdpa_ndev(mvdev);
 	struct mlx5_vdpa_virtqueue *mvq;
 
-	if (!is_index_valid(mvdev, idx))
+	if (!is_index_valid(mvdev, idx) || is_ctrl_vq_idx(mvdev, idx))
 		return;
 
 	mvq = &ndev->vqs[idx];
@@ -1410,15 +1548,42 @@ static void mlx5_vdpa_set_vq_cb(struct vdpa_device *vdev, u16 idx, struct vdpa_c
 	ndev->event_cbs[idx] = *cb;
 }
 
+static void mlx5_cvq_notify(struct vringh *vring)
+{
+	struct mlx5_control_vq *cvq = container_of(vring, struct mlx5_control_vq, vring);
+
+	if (!cvq->event_cb.callback)
+		return;
+
+	cvq->event_cb.callback(cvq->event_cb.private);
+}
+
+static void set_cvq_ready(struct mlx5_vdpa_dev *mvdev, bool ready)
+{
+	struct mlx5_control_vq *cvq = &mvdev->cvq;
+
+	cvq->ready = ready;
+	if (!ready)
+		return;
+
+	cvq->vring.notify = mlx5_cvq_notify;
+}
+
 static void mlx5_vdpa_set_vq_ready(struct vdpa_device *vdev, u16 idx, bool ready)
 {
 	struct mlx5_vdpa_dev *mvdev = to_mvdev(vdev);
 	struct mlx5_vdpa_net *ndev = to_mlx5_vdpa_ndev(mvdev);
-	struct mlx5_vdpa_virtqueue *mvq = &ndev->vqs[idx];
+	struct mlx5_vdpa_virtqueue *mvq;
 
 	if (!is_index_valid(mvdev, idx))
 		return;
 
+	if (is_ctrl_vq_idx(mvdev, idx)) {
+		set_cvq_ready(mvdev, ready);
+		return;
+	}
+
+	mvq = &ndev->vqs[idx];
 	if (!ready)
 		suspend_vq(ndev, mvq);
 
@@ -1429,12 +1594,14 @@ static bool mlx5_vdpa_get_vq_ready(struct vdpa_device *vdev, u16 idx)
 {
 	struct mlx5_vdpa_dev *mvdev = to_mvdev(vdev);
 	struct mlx5_vdpa_net *ndev = to_mlx5_vdpa_ndev(mvdev);
-	struct mlx5_vdpa_virtqueue *mvq = &ndev->vqs[idx];
 
 	if (!is_index_valid(mvdev, idx))
 		return false;
 
-	return mvq->ready;
+	if (is_ctrl_vq_idx(mvdev, idx))
+		return mvdev->cvq.ready;
+
+	return ndev->vqs[idx].ready;
 }
 
 static int mlx5_vdpa_set_vq_state(struct vdpa_device *vdev, u16 idx,
@@ -1442,11 +1609,17 @@ static int mlx5_vdpa_set_vq_state(struct vdpa_device *vdev, u16 idx,
 {
 	struct mlx5_vdpa_dev *mvdev = to_mvdev(vdev);
 	struct mlx5_vdpa_net *ndev = to_mlx5_vdpa_ndev(mvdev);
-	struct mlx5_vdpa_virtqueue *mvq = &ndev->vqs[idx];
+	struct mlx5_vdpa_virtqueue *mvq;
 
 	if (!is_index_valid(mvdev, idx))
 		return -EINVAL;
 
+	if (is_ctrl_vq_idx(mvdev, idx)) {
+		mvdev->cvq.vring.last_avail_idx = state->split.avail_index;
+		return 0;
+	}
+
+	mvq = &ndev->vqs[idx];
 	if (mvq->fw_state == MLX5_VIRTIO_NET_Q_OBJECT_STATE_RDY) {
 		mlx5_vdpa_warn(mvdev, "can't modify available index\n");
 		return -EINVAL;
@@ -1461,13 +1634,19 @@ static int mlx5_vdpa_get_vq_state(struct vdpa_device *vdev, u16 idx, struct vdpa
 {
 	struct mlx5_vdpa_dev *mvdev = to_mvdev(vdev);
 	struct mlx5_vdpa_net *ndev = to_mlx5_vdpa_ndev(mvdev);
-	struct mlx5_vdpa_virtqueue *mvq = &ndev->vqs[idx];
+	struct mlx5_vdpa_virtqueue *mvq;
 	struct mlx5_virtq_attr attr;
 	int err;
 
 	if (!is_index_valid(mvdev, idx))
 		return -EINVAL;
 
+	if (is_ctrl_vq_idx(mvdev, idx)) {
+		state->split.avail_index = mvdev->cvq.vring.last_avail_idx;
+		return 0;
+	}
+
+	mvq = &ndev->vqs[idx];
 	/* If the virtq object was destroyed, use the value saved at
 	 * the last minute of suspend_vq. This caters for userspace
 	 * that cares about emulating the index after vq is stopped.
@@ -1524,10 +1703,13 @@ static u64 mlx5_vdpa_get_features(struct vdpa_device *vdev)
 	u16 dev_features;
 
 	dev_features = MLX5_CAP_DEV_VDPA_EMULATION(mvdev->mdev, device_features_bits_mask);
-	ndev->mvdev.mlx_features = mlx_to_vritio_features(dev_features);
+	ndev->mvdev.mlx_features |= mlx_to_vritio_features(dev_features);
 	if (MLX5_CAP_DEV_VDPA_EMULATION(mvdev->mdev, virtio_version_1_0))
 		ndev->mvdev.mlx_features |= BIT_ULL(VIRTIO_F_VERSION_1);
 	ndev->mvdev.mlx_features |= BIT_ULL(VIRTIO_F_ACCESS_PLATFORM);
+	ndev->mvdev.mlx_features |= BIT_ULL(VIRTIO_NET_F_CTRL_VQ);
+	ndev->mvdev.mlx_features |= BIT_ULL(VIRTIO_NET_F_CTRL_MAC_ADDR);
+
 	print_features(mvdev, ndev->mvdev.mlx_features, false);
 	return ndev->mvdev.mlx_features;
 }
@@ -1543,6 +1725,7 @@ static int verify_min_features(struct mlx5_vdpa_dev *mvdev, u64 features)
 static int setup_virtqueues(struct mlx5_vdpa_dev *mvdev)
 {
 	struct mlx5_vdpa_net *ndev = to_mlx5_vdpa_ndev(mvdev);
+	struct mlx5_control_vq *cvq = &mvdev->cvq;
 	int err;
 	int i;
 
@@ -1552,6 +1735,16 @@ static int setup_virtqueues(struct mlx5_vdpa_dev *mvdev)
 			goto err_vq;
 	}
 
+	if (mvdev->actual_features & BIT_ULL(VIRTIO_NET_F_CTRL_VQ)) {
+		err = vringh_init_iotlb(&cvq->vring, mvdev->actual_features,
+					MLX5_CVQ_MAX_ENT, false,
+					(struct vring_desc *)(uintptr_t)cvq->desc_addr,
+					(struct vring_avail *)(uintptr_t)cvq->driver_addr,
+					(struct vring_used *)(uintptr_t)cvq->device_addr);
+		if (err)
+			goto err_vq;
+	}
+
 	return 0;
 
 err_vq:
@@ -1943,7 +2136,7 @@ static struct vdpa_notification_area mlx5_get_vq_notification(struct vdpa_device
 	struct mlx5_vdpa_net *ndev;
 	phys_addr_t addr;
 
-	if (!is_index_valid(mvdev, idx))
+	if (!is_index_valid(mvdev, idx) || is_ctrl_vq_idx(mvdev, idx))
 		return ret;
 
 	/* If SF BAR size is smaller than PAGE_SIZE, do not use direct
@@ -2120,8 +2313,11 @@ static int mlx5_vdpa_dev_add(struct vdpa_mgmt_dev *v_mdev, const char *name)
 		err = mlx5_mpfs_add_mac(pfmdev, config->mac);
 		if (err)
 			goto err_mtu;
+
+		ndev->mvdev.mlx_features |= BIT_ULL(VIRTIO_NET_F_MAC);
 	}
 
+	config->max_virtqueue_pairs = cpu_to_mlx5vdpa16(mvdev, mlx5_vdpa_max_qps(max_vqs));
 	mvdev->vdev.dma_dev = &mdev->pdev->dev;
 	err = mlx5_vdpa_alloc_resources(&ndev->mvdev);
 	if (err)
@@ -2137,8 +2333,15 @@ static int mlx5_vdpa_dev_add(struct vdpa_mgmt_dev *v_mdev, const char *name)
 	if (err)
 		goto err_mr;
 
+	mvdev->wq = create_singlethread_workqueue("mlx5_vdpa_ctrl_wq");
+	if (!mvdev->wq) {
+		err = -ENOMEM;
+		goto err_res2;
+	}
+
+	ndev->cur_num_vqs = 2 * mlx5_vdpa_max_qps(max_vqs);
 	mvdev->vdev.mdev = &mgtdev->mgtdev;
-	err = _vdpa_register_device(&mvdev->vdev, 2 * mlx5_vdpa_max_qps(max_vqs));
+	err = _vdpa_register_device(&mvdev->vdev, ndev->cur_num_vqs + 1);
 	if (err)
 		goto err_reg;
 
@@ -2146,6 +2349,8 @@ static int mlx5_vdpa_dev_add(struct vdpa_mgmt_dev *v_mdev, const char *name)
 	return 0;
 
 err_reg:
+	destroy_workqueue(mvdev->wq);
+err_res2:
 	free_resources(ndev);
 err_mr:
 	mlx5_vdpa_destroy_mr(mvdev);
@@ -2163,7 +2368,9 @@ err_mtu:
 static void mlx5_vdpa_dev_del(struct vdpa_mgmt_dev *v_mdev, struct vdpa_device *dev)
 {
 	struct mlx5_vdpa_mgmtdev *mgtdev = container_of(v_mdev, struct mlx5_vdpa_mgmtdev, mgtdev);
+	struct mlx5_vdpa_dev *mvdev = to_mvdev(dev);
 
+	destroy_workqueue(mvdev->wq);
 	_vdpa_unregister_device(dev);
 	mgtdev->ndev = NULL;
 }
-- 
cgit v1.2.3


From 52893733f2c5886fc74be6c386d12b59a3f581df Mon Sep 17 00:00:00 2001
From: Eli Cohen <elic@nvidia.com>
Date: Mon, 23 Aug 2021 08:21:23 +0300
Subject: vdpa/mlx5: Add multiqueue support

Multiqueue support requires additional virtio_net_q objects to be added
or removed per the configured number of queue pairs. In addition the RQ
tables needs to be modified to match the number of configured receive
queues so the packets are dispatched to the right virtqueue according to
the hash result.

Note: qemu v6.0.0 is broken when the device requests more than two data
queues; no net device will be created for the vdpa device. To avoid
this, one should specify mq=off to qemu. In this case it will end up
with a single queue.

Signed-off-by: Eli Cohen <elic@nvidia.com>
Link: https://lore.kernel.org/r/20210823052123.14909-7-elic@nvidia.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
 drivers/vdpa/mlx5/core/mlx5_vdpa.h |   1 +
 drivers/vdpa/mlx5/core/resources.c |  10 ++
 drivers/vdpa/mlx5/net/mlx5_vnet.c  | 189 +++++++++++++++++++++++++++++++------
 3 files changed, 169 insertions(+), 31 deletions(-)

(limited to 'drivers/vdpa')

diff --git a/drivers/vdpa/mlx5/core/mlx5_vdpa.h b/drivers/vdpa/mlx5/core/mlx5_vdpa.h
index 6c43476a69cb..01a848adf590 100644
--- a/drivers/vdpa/mlx5/core/mlx5_vdpa.h
+++ b/drivers/vdpa/mlx5/core/mlx5_vdpa.h
@@ -91,6 +91,7 @@ int mlx5_vdpa_get_null_mkey(struct mlx5_vdpa_dev *dev, u32 *null_mkey);
 int mlx5_vdpa_create_tis(struct mlx5_vdpa_dev *mvdev, void *in, u32 *tisn);
 void mlx5_vdpa_destroy_tis(struct mlx5_vdpa_dev *mvdev, u32 tisn);
 int mlx5_vdpa_create_rqt(struct mlx5_vdpa_dev *mvdev, void *in, int inlen, u32 *rqtn);
+int mlx5_vdpa_modify_rqt(struct mlx5_vdpa_dev *mvdev, void *in, int inlen, u32 rqtn);
 void mlx5_vdpa_destroy_rqt(struct mlx5_vdpa_dev *mvdev, u32 rqtn);
 int mlx5_vdpa_create_tir(struct mlx5_vdpa_dev *mvdev, void *in, u32 *tirn);
 void mlx5_vdpa_destroy_tir(struct mlx5_vdpa_dev *mvdev, u32 tirn);
diff --git a/drivers/vdpa/mlx5/core/resources.c b/drivers/vdpa/mlx5/core/resources.c
index b3c08dfa98e8..15e266d0e27a 100644
--- a/drivers/vdpa/mlx5/core/resources.c
+++ b/drivers/vdpa/mlx5/core/resources.c
@@ -129,6 +129,16 @@ int mlx5_vdpa_create_rqt(struct mlx5_vdpa_dev *mvdev, void *in, int inlen, u32 *
 	return err;
 }
 
+int mlx5_vdpa_modify_rqt(struct mlx5_vdpa_dev *mvdev, void *in, int inlen, u32 rqtn)
+{
+	u32 out[MLX5_ST_SZ_DW(create_rqt_out)] = {};
+
+	MLX5_SET(modify_rqt_in, in, uid, mvdev->res.uid);
+	MLX5_SET(modify_rqt_in, in, rqtn, rqtn);
+	MLX5_SET(modify_rqt_in, in, opcode, MLX5_CMD_OP_MODIFY_RQT);
+	return mlx5_cmd_exec(mvdev->mdev, in, inlen, out, sizeof(out));
+}
+
 void mlx5_vdpa_destroy_rqt(struct mlx5_vdpa_dev *mvdev, u32 rqtn)
 {
 	u32 in[MLX5_ST_SZ_DW(destroy_rqt_in)] = {};
diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c
index 1b208aa656cb..4ba3ac48ee83 100644
--- a/drivers/vdpa/mlx5/net/mlx5_vnet.c
+++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c
@@ -133,7 +133,7 @@ struct mlx5_vdpa_virtqueue {
 /* We will remove this limitation once mlx5_vdpa_alloc_resources()
  * provides for driver space allocation
  */
-#define MLX5_MAX_SUPPORTED_VQS 2
+#define MLX5_MAX_SUPPORTED_VQS 16
 
 static bool is_index_valid(struct mlx5_vdpa_dev *mvdev, u16 idx)
 {
@@ -184,6 +184,23 @@ static bool mlx5_vdpa_debug;
 			mlx5_vdpa_info(mvdev, "%s\n", #_status);                                   \
 	} while (0)
 
+/* TODO: cross-endian support */
+static inline bool mlx5_vdpa_is_little_endian(struct mlx5_vdpa_dev *mvdev)
+{
+	return virtio_legacy_is_little_endian() ||
+		(mvdev->actual_features & BIT_ULL(VIRTIO_F_VERSION_1));
+}
+
+static u16 mlx5vdpa16_to_cpu(struct mlx5_vdpa_dev *mvdev, __virtio16 val)
+{
+	return __virtio16_to_cpu(mlx5_vdpa_is_little_endian(mvdev), val);
+}
+
+static __virtio16 cpu_to_mlx5vdpa16(struct mlx5_vdpa_dev *mvdev, u16 val)
+{
+	return __cpu_to_virtio16(mlx5_vdpa_is_little_endian(mvdev), val);
+}
+
 static inline u32 mlx5_vdpa_max_qps(int max_vqs)
 {
 	return max_vqs / 2;
@@ -191,6 +208,9 @@ static inline u32 mlx5_vdpa_max_qps(int max_vqs)
 
 static u16 ctrl_vq_idx(struct mlx5_vdpa_dev *mvdev)
 {
+	if (!(mvdev->actual_features & BIT_ULL(VIRTIO_NET_F_MQ)))
+		return 2;
+
 	return 2 * mlx5_vdpa_max_qps(mvdev->max_vqs);
 }
 
@@ -1126,10 +1146,8 @@ static int setup_vq(struct mlx5_vdpa_net *ndev, struct mlx5_vdpa_virtqueue *mvq)
 	if (!mvq->num_ent)
 		return 0;
 
-	if (mvq->initialized) {
-		mlx5_vdpa_warn(&ndev->mvdev, "attempt re init\n");
-		return -EINVAL;
-	}
+	if (mvq->initialized)
+		return 0;
 
 	err = cq_create(ndev, idx, mvq->num_ent);
 	if (err)
@@ -1216,19 +1234,20 @@ static void teardown_vq(struct mlx5_vdpa_net *ndev, struct mlx5_vdpa_virtqueue *
 
 static int create_rqt(struct mlx5_vdpa_net *ndev)
 {
-	int log_max_rqt;
 	__be32 *list;
+	int max_rqt;
 	void *rqtc;
 	int inlen;
 	void *in;
 	int i, j;
 	int err;
 
-	log_max_rqt = min_t(int, 1, MLX5_CAP_GEN(ndev->mvdev.mdev, log_max_rqt_size));
-	if (log_max_rqt < 1)
+	max_rqt = min_t(int, MLX5_MAX_SUPPORTED_VQS / 2,
+			1 << MLX5_CAP_GEN(ndev->mvdev.mdev, log_max_rqt_size));
+	if (max_rqt < 1)
 		return -EOPNOTSUPP;
 
-	inlen = MLX5_ST_SZ_BYTES(create_rqt_in) + (1 << log_max_rqt) * MLX5_ST_SZ_BYTES(rq_num);
+	inlen = MLX5_ST_SZ_BYTES(create_rqt_in) + max_rqt * MLX5_ST_SZ_BYTES(rq_num);
 	in = kzalloc(inlen, GFP_KERNEL);
 	if (!in)
 		return -ENOMEM;
@@ -1237,10 +1256,9 @@ static int create_rqt(struct mlx5_vdpa_net *ndev)
 	rqtc = MLX5_ADDR_OF(create_rqt_in, in, rqt_context);
 
 	MLX5_SET(rqtc, rqtc, list_q_type, MLX5_RQTC_LIST_Q_TYPE_VIRTIO_NET_Q);
-	MLX5_SET(rqtc, rqtc, rqt_max_size, 1 << log_max_rqt);
-	MLX5_SET(rqtc, rqtc, rqt_actual_size, 1);
+	MLX5_SET(rqtc, rqtc, rqt_max_size, max_rqt);
 	list = MLX5_ADDR_OF(rqtc, rqtc, rq_num[0]);
-	for (i = 0, j = 0; j < ndev->mvdev.max_vqs; j++) {
+	for (i = 0, j = 0; j < max_rqt; j++) {
 		if (!ndev->vqs[j].initialized)
 			continue;
 
@@ -1249,6 +1267,7 @@ static int create_rqt(struct mlx5_vdpa_net *ndev)
 			i++;
 		}
 	}
+	MLX5_SET(rqtc, rqtc, rqt_actual_size, i);
 
 	err = mlx5_vdpa_create_rqt(&ndev->mvdev, in, inlen, &ndev->res.rqtn);
 	kfree(in);
@@ -1258,6 +1277,52 @@ static int create_rqt(struct mlx5_vdpa_net *ndev)
 	return 0;
 }
 
+#define MLX5_MODIFY_RQT_NUM_RQS ((u64)1)
+
+static int modify_rqt(struct mlx5_vdpa_net *ndev, int num)
+{
+	__be32 *list;
+	int max_rqt;
+	void *rqtc;
+	int inlen;
+	void *in;
+	int i, j;
+	int err;
+
+	max_rqt = min_t(int, ndev->cur_num_vqs / 2,
+			1 << MLX5_CAP_GEN(ndev->mvdev.mdev, log_max_rqt_size));
+	if (max_rqt < 1)
+		return -EOPNOTSUPP;
+
+	inlen = MLX5_ST_SZ_BYTES(modify_rqt_in) + max_rqt * MLX5_ST_SZ_BYTES(rq_num);
+	in = kzalloc(inlen, GFP_KERNEL);
+	if (!in)
+		return -ENOMEM;
+
+	MLX5_SET(modify_rqt_in, in, uid, ndev->mvdev.res.uid);
+	MLX5_SET64(modify_rqt_in, in, bitmask, MLX5_MODIFY_RQT_NUM_RQS);
+	rqtc = MLX5_ADDR_OF(modify_rqt_in, in, ctx);
+	MLX5_SET(rqtc, rqtc, list_q_type, MLX5_RQTC_LIST_Q_TYPE_VIRTIO_NET_Q);
+
+	list = MLX5_ADDR_OF(rqtc, rqtc, rq_num[0]);
+	for (i = 0, j = 0; j < num; j++) {
+		if (!ndev->vqs[j].initialized)
+			continue;
+
+		if (!vq_is_tx(ndev->vqs[j].index)) {
+			list[i] = cpu_to_be32(ndev->vqs[j].virtq_id);
+			i++;
+		}
+	}
+	MLX5_SET(rqtc, rqtc, rqt_actual_size, i);
+	err = mlx5_vdpa_modify_rqt(&ndev->mvdev, in, inlen, ndev->res.rqtn);
+	kfree(in);
+	if (err)
+		return err;
+
+	return 0;
+}
+
 static void destroy_rqt(struct mlx5_vdpa_net *ndev)
 {
 	mlx5_vdpa_destroy_rqt(&ndev->mvdev, ndev->res.rqtn);
@@ -1417,6 +1482,77 @@ static virtio_net_ctrl_ack handle_ctrl_mac(struct mlx5_vdpa_dev *mvdev, u8 cmd)
 	return status;
 }
 
+static int change_num_qps(struct mlx5_vdpa_dev *mvdev, int newqps)
+{
+	struct mlx5_vdpa_net *ndev = to_mlx5_vdpa_ndev(mvdev);
+	int cur_qps = ndev->cur_num_vqs / 2;
+	int err;
+	int i;
+
+	if (cur_qps > newqps) {
+		err = modify_rqt(ndev, 2 * newqps);
+		if (err)
+			return err;
+
+		for (i = ndev->cur_num_vqs - 1; i >= 2 * newqps; i--)
+			teardown_vq(ndev, &ndev->vqs[i]);
+
+		ndev->cur_num_vqs = 2 * newqps;
+	} else {
+		ndev->cur_num_vqs = 2 * newqps;
+		for (i = cur_qps * 2; i < 2 * newqps; i++) {
+			err = setup_vq(ndev, &ndev->vqs[i]);
+			if (err)
+				goto clean_added;
+		}
+		err = modify_rqt(ndev, 2 * newqps);
+		if (err)
+			goto clean_added;
+	}
+	return 0;
+
+clean_added:
+	for (--i; i >= cur_qps; --i)
+		teardown_vq(ndev, &ndev->vqs[i]);
+
+	return err;
+}
+
+static virtio_net_ctrl_ack handle_ctrl_mq(struct mlx5_vdpa_dev *mvdev, u8 cmd)
+{
+	struct mlx5_vdpa_net *ndev = to_mlx5_vdpa_ndev(mvdev);
+	virtio_net_ctrl_ack status = VIRTIO_NET_ERR;
+	struct mlx5_control_vq *cvq = &mvdev->cvq;
+	struct virtio_net_ctrl_mq mq;
+	size_t read;
+	u16 newqps;
+
+	switch (cmd) {
+	case VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET:
+		read = vringh_iov_pull_iotlb(&cvq->vring, &cvq->riov, (void *)&mq, sizeof(mq));
+		if (read != sizeof(mq))
+			break;
+
+		newqps = mlx5vdpa16_to_cpu(mvdev, mq.virtqueue_pairs);
+		if (ndev->cur_num_vqs == 2 * newqps) {
+			status = VIRTIO_NET_OK;
+			break;
+		}
+
+		if (newqps & (newqps - 1))
+			break;
+
+		if (!change_num_qps(mvdev, newqps))
+			status = VIRTIO_NET_OK;
+
+		break;
+	default:
+		break;
+	}
+
+	return status;
+}
+
 static void mlx5_cvq_kick_handler(struct work_struct *work)
 {
 	virtio_net_ctrl_ack status = VIRTIO_NET_ERR;
@@ -1452,6 +1588,9 @@ static void mlx5_cvq_kick_handler(struct work_struct *work)
 		case VIRTIO_NET_CTRL_MAC:
 			status = handle_ctrl_mac(mvdev, ctrl.cmd);
 			break;
+		case VIRTIO_NET_CTRL_MQ:
+			status = handle_ctrl_mq(mvdev, ctrl.cmd);
+			break;
 
 		default:
 			break;
@@ -1709,6 +1848,7 @@ static u64 mlx5_vdpa_get_features(struct vdpa_device *vdev)
 	ndev->mvdev.mlx_features |= BIT_ULL(VIRTIO_F_ACCESS_PLATFORM);
 	ndev->mvdev.mlx_features |= BIT_ULL(VIRTIO_NET_F_CTRL_VQ);
 	ndev->mvdev.mlx_features |= BIT_ULL(VIRTIO_NET_F_CTRL_MAC_ADDR);
+	ndev->mvdev.mlx_features |= BIT_ULL(VIRTIO_NET_F_MQ);
 
 	print_features(mvdev, ndev->mvdev.mlx_features, false);
 	return ndev->mvdev.mlx_features;
@@ -1768,18 +1908,6 @@ static void teardown_virtqueues(struct mlx5_vdpa_net *ndev)
 	}
 }
 
-/* TODO: cross-endian support */
-static inline bool mlx5_vdpa_is_little_endian(struct mlx5_vdpa_dev *mvdev)
-{
-	return virtio_legacy_is_little_endian() ||
-		(mvdev->actual_features & BIT_ULL(VIRTIO_F_VERSION_1));
-}
-
-static __virtio16 cpu_to_mlx5vdpa16(struct mlx5_vdpa_dev *mvdev, u16 val)
-{
-	return __cpu_to_virtio16(mlx5_vdpa_is_little_endian(mvdev), val);
-}
-
 static void update_cvq_info(struct mlx5_vdpa_dev *mvdev)
 {
 	if (MLX5_FEATURE(mvdev, VIRTIO_NET_F_CTRL_VQ)) {
@@ -1851,15 +1979,14 @@ static u8 mlx5_vdpa_get_status(struct vdpa_device *vdev)
 static int save_channel_info(struct mlx5_vdpa_net *ndev, struct mlx5_vdpa_virtqueue *mvq)
 {
 	struct mlx5_vq_restore_info *ri = &mvq->ri;
-	struct mlx5_virtq_attr attr;
+	struct mlx5_virtq_attr attr = {};
 	int err;
 
-	if (!mvq->initialized)
-		return 0;
-
-	err = query_virtqueue(ndev, mvq, &attr);
-	if (err)
-		return err;
+	if (mvq->initialized) {
+		err = query_virtqueue(ndev, mvq, &attr);
+		if (err)
+			return err;
+	}
 
 	ri->avail_index = attr.available_index;
 	ri->used_index = attr.used_index;
-- 
cgit v1.2.3


From 0d8c9e7d4b403f10f5c277efefd787244198a00c Mon Sep 17 00:00:00 2001
From: Xie Yongji <xieyongji@bytedance.com>
Date: Mon, 9 Aug 2021 18:09:23 +0800
Subject: vdpa_sim: Use iova_shift() for the size passed to alloc_iova()

The size passed to alloc_iova() should be the size of page frames.
Now we use byte granularity for the iova domain, so it's safe to
pass the size in bytes to alloc_iova(). But it would be better to use
iova_shift() for the size to avoid future bugs if we change granularity.

Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Link: https://lore.kernel.org/r/20210809100923.38-1-xieyongji@bytedance.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
---
 drivers/vdpa/vdpa_sim/vdpa_sim.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

(limited to 'drivers/vdpa')

diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.c b/drivers/vdpa/vdpa_sim/vdpa_sim.c
index c621cf7feec0..5b51d0ac8bae 100644
--- a/drivers/vdpa/vdpa_sim/vdpa_sim.c
+++ b/drivers/vdpa/vdpa_sim/vdpa_sim.c
@@ -137,7 +137,8 @@ static dma_addr_t vdpasim_map_range(struct vdpasim *vdpasim, phys_addr_t paddr,
 	int ret;
 
 	/* We set the limit_pfn to the maximum (ULONG_MAX - 1) */
-	iova = alloc_iova(&vdpasim->iova, size, ULONG_MAX - 1, true);
+	iova = alloc_iova(&vdpasim->iova, size >> iova_shift(&vdpasim->iova),
+			  ULONG_MAX - 1, true);
 	if (!iova)
 		return DMA_MAPPING_ERROR;
 
-- 
cgit v1.2.3


From 0686082dbf7a204ca0fab326a820779e31666639 Mon Sep 17 00:00:00 2001
From: Xie Yongji <xieyongji@bytedance.com>
Date: Tue, 31 Aug 2021 18:36:26 +0800
Subject: vdpa: Add reset callback in vdpa_config_ops

This adds a new callback to support device specific reset
behavior. The vdpa bus driver will call the reset function
instead of setting status to zero during resetting.

Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Link: https://lore.kernel.org/r/20210831103634.33-6-xieyongji@bytedance.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
 drivers/vdpa/ifcvf/ifcvf_main.c   | 35 +++++++++++++++++++++++-----------
 drivers/vdpa/mlx5/net/mlx5_vnet.c | 40 +++++++++++++++++++++++----------------
 drivers/vdpa/vdpa_sim/vdpa_sim.c  | 18 +++++++++++++++---
 drivers/vdpa/virtio_pci/vp_vdpa.c | 15 +++++++++++++--
 drivers/vhost/vdpa.c              |  9 +++++++--
 include/linux/vdpa.h              |  8 ++++++--
 6 files changed, 89 insertions(+), 36 deletions(-)

(limited to 'drivers/vdpa')

diff --git a/drivers/vdpa/ifcvf/ifcvf_main.c b/drivers/vdpa/ifcvf/ifcvf_main.c
index bfc3d7d40c09..4293481ce910 100644
--- a/drivers/vdpa/ifcvf/ifcvf_main.c
+++ b/drivers/vdpa/ifcvf/ifcvf_main.c
@@ -222,17 +222,6 @@ static void ifcvf_vdpa_set_status(struct vdpa_device *vdpa_dev, u8 status)
 	if (status_old == status)
 		return;
 
-	if ((status_old & VIRTIO_CONFIG_S_DRIVER_OK) &&
-	    !(status & VIRTIO_CONFIG_S_DRIVER_OK)) {
-		ifcvf_stop_datapath(adapter);
-		ifcvf_free_irq(adapter, vf->nr_vring);
-	}
-
-	if (status == 0) {
-		ifcvf_reset_vring(adapter);
-		return;
-	}
-
 	if ((status & VIRTIO_CONFIG_S_DRIVER_OK) &&
 	    !(status_old & VIRTIO_CONFIG_S_DRIVER_OK)) {
 		ret = ifcvf_request_irq(adapter);
@@ -252,6 +241,29 @@ static void ifcvf_vdpa_set_status(struct vdpa_device *vdpa_dev, u8 status)
 	ifcvf_set_status(vf, status);
 }
 
+static int ifcvf_vdpa_reset(struct vdpa_device *vdpa_dev)
+{
+	struct ifcvf_adapter *adapter;
+	struct ifcvf_hw *vf;
+	u8 status_old;
+
+	vf  = vdpa_to_vf(vdpa_dev);
+	adapter = vdpa_to_adapter(vdpa_dev);
+	status_old = ifcvf_get_status(vf);
+
+	if (status_old == 0)
+		return 0;
+
+	if (status_old & VIRTIO_CONFIG_S_DRIVER_OK) {
+		ifcvf_stop_datapath(adapter);
+		ifcvf_free_irq(adapter, vf->nr_vring);
+	}
+
+	ifcvf_reset_vring(adapter);
+
+	return 0;
+}
+
 static u16 ifcvf_vdpa_get_vq_num_max(struct vdpa_device *vdpa_dev)
 {
 	return IFCVF_QUEUE_MAX;
@@ -435,6 +447,7 @@ static const struct vdpa_config_ops ifc_vdpa_ops = {
 	.set_features	= ifcvf_vdpa_set_features,
 	.get_status	= ifcvf_vdpa_get_status,
 	.set_status	= ifcvf_vdpa_set_status,
+	.reset		= ifcvf_vdpa_reset,
 	.get_vq_num_max	= ifcvf_vdpa_get_vq_num_max,
 	.get_vq_state	= ifcvf_vdpa_get_vq_state,
 	.set_vq_state	= ifcvf_vdpa_set_vq_state,
diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c
index 4ba3ac48ee83..608f6b900cd9 100644
--- a/drivers/vdpa/mlx5/net/mlx5_vnet.c
+++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c
@@ -2154,22 +2154,6 @@ static void mlx5_vdpa_set_status(struct vdpa_device *vdev, u8 status)
 	int err;
 
 	print_status(mvdev, status, true);
-	if (!status) {
-		mlx5_vdpa_info(mvdev, "performing device reset\n");
-		teardown_driver(ndev);
-		clear_vqs_ready(ndev);
-		mlx5_vdpa_destroy_mr(&ndev->mvdev);
-		ndev->mvdev.status = 0;
-		ndev->mvdev.mlx_features = 0;
-		memset(ndev->event_cbs, 0, sizeof(ndev->event_cbs));
-		ndev->mvdev.actual_features = 0;
-		++mvdev->generation;
-		if (MLX5_CAP_GEN(mvdev->mdev, umem_uid_0)) {
-			if (mlx5_vdpa_create_mr(mvdev, NULL))
-				mlx5_vdpa_warn(mvdev, "create MR failed\n");
-		}
-		return;
-	}
 
 	if ((status ^ ndev->mvdev.status) & VIRTIO_CONFIG_S_DRIVER_OK) {
 		if (status & VIRTIO_CONFIG_S_DRIVER_OK) {
@@ -2192,6 +2176,29 @@ err_setup:
 	ndev->mvdev.status |= VIRTIO_CONFIG_S_FAILED;
 }
 
+static int mlx5_vdpa_reset(struct vdpa_device *vdev)
+{
+	struct mlx5_vdpa_dev *mvdev = to_mvdev(vdev);
+	struct mlx5_vdpa_net *ndev = to_mlx5_vdpa_ndev(mvdev);
+
+	print_status(mvdev, 0, true);
+	mlx5_vdpa_info(mvdev, "performing device reset\n");
+	teardown_driver(ndev);
+	clear_vqs_ready(ndev);
+	mlx5_vdpa_destroy_mr(&ndev->mvdev);
+	ndev->mvdev.status = 0;
+	ndev->mvdev.mlx_features = 0;
+	memset(ndev->event_cbs, 0, sizeof(ndev->event_cbs));
+	ndev->mvdev.actual_features = 0;
+	++mvdev->generation;
+	if (MLX5_CAP_GEN(mvdev->mdev, umem_uid_0)) {
+		if (mlx5_vdpa_create_mr(mvdev, NULL))
+			mlx5_vdpa_warn(mvdev, "create MR failed\n");
+	}
+
+	return 0;
+}
+
 static size_t mlx5_vdpa_get_config_size(struct vdpa_device *vdev)
 {
 	return sizeof(struct virtio_net_config);
@@ -2305,6 +2312,7 @@ static const struct vdpa_config_ops mlx5_vdpa_ops = {
 	.get_vendor_id = mlx5_vdpa_get_vendor_id,
 	.get_status = mlx5_vdpa_get_status,
 	.set_status = mlx5_vdpa_set_status,
+	.reset = mlx5_vdpa_reset,
 	.get_config_size = mlx5_vdpa_get_config_size,
 	.get_config = mlx5_vdpa_get_config,
 	.set_config = mlx5_vdpa_set_config,
diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.c b/drivers/vdpa/vdpa_sim/vdpa_sim.c
index 5b51d0ac8bae..f292bb05d6c9 100644
--- a/drivers/vdpa/vdpa_sim/vdpa_sim.c
+++ b/drivers/vdpa/vdpa_sim/vdpa_sim.c
@@ -92,7 +92,7 @@ static void vdpasim_vq_reset(struct vdpasim *vdpasim,
 	vq->vring.notify = NULL;
 }
 
-static void vdpasim_reset(struct vdpasim *vdpasim)
+static void vdpasim_do_reset(struct vdpasim *vdpasim)
 {
 	int i;
 
@@ -460,11 +460,21 @@ static void vdpasim_set_status(struct vdpa_device *vdpa, u8 status)
 
 	spin_lock(&vdpasim->lock);
 	vdpasim->status = status;
-	if (status == 0)
-		vdpasim_reset(vdpasim);
 	spin_unlock(&vdpasim->lock);
 }
 
+static int vdpasim_reset(struct vdpa_device *vdpa)
+{
+	struct vdpasim *vdpasim = vdpa_to_sim(vdpa);
+
+	spin_lock(&vdpasim->lock);
+	vdpasim->status = 0;
+	vdpasim_do_reset(vdpasim);
+	spin_unlock(&vdpasim->lock);
+
+	return 0;
+}
+
 static size_t vdpasim_get_config_size(struct vdpa_device *vdpa)
 {
 	struct vdpasim *vdpasim = vdpa_to_sim(vdpa);
@@ -608,6 +618,7 @@ static const struct vdpa_config_ops vdpasim_config_ops = {
 	.get_vendor_id          = vdpasim_get_vendor_id,
 	.get_status             = vdpasim_get_status,
 	.set_status             = vdpasim_set_status,
+	.reset			= vdpasim_reset,
 	.get_config_size        = vdpasim_get_config_size,
 	.get_config             = vdpasim_get_config,
 	.set_config             = vdpasim_set_config,
@@ -636,6 +647,7 @@ static const struct vdpa_config_ops vdpasim_batch_config_ops = {
 	.get_vendor_id          = vdpasim_get_vendor_id,
 	.get_status             = vdpasim_get_status,
 	.set_status             = vdpasim_set_status,
+	.reset			= vdpasim_reset,
 	.get_config_size        = vdpasim_get_config_size,
 	.get_config             = vdpasim_get_config,
 	.set_config             = vdpasim_set_config,
diff --git a/drivers/vdpa/virtio_pci/vp_vdpa.c b/drivers/vdpa/virtio_pci/vp_vdpa.c
index fe0527329857..cd7718b43a6e 100644
--- a/drivers/vdpa/virtio_pci/vp_vdpa.c
+++ b/drivers/vdpa/virtio_pci/vp_vdpa.c
@@ -189,10 +189,20 @@ static void vp_vdpa_set_status(struct vdpa_device *vdpa, u8 status)
 	}
 
 	vp_modern_set_status(mdev, status);
+}
 
-	if (!(status & VIRTIO_CONFIG_S_DRIVER_OK) &&
-	    (s & VIRTIO_CONFIG_S_DRIVER_OK))
+static int vp_vdpa_reset(struct vdpa_device *vdpa)
+{
+	struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa);
+	struct virtio_pci_modern_device *mdev = &vp_vdpa->mdev;
+	u8 s = vp_vdpa_get_status(vdpa);
+
+	vp_modern_set_status(mdev, 0);
+
+	if (s & VIRTIO_CONFIG_S_DRIVER_OK)
 		vp_vdpa_free_irq(vp_vdpa);
+
+	return 0;
 }
 
 static u16 vp_vdpa_get_vq_num_max(struct vdpa_device *vdpa)
@@ -398,6 +408,7 @@ static const struct vdpa_config_ops vp_vdpa_ops = {
 	.set_features	= vp_vdpa_set_features,
 	.get_status	= vp_vdpa_get_status,
 	.set_status	= vp_vdpa_set_status,
+	.reset		= vp_vdpa_reset,
 	.get_vq_num_max	= vp_vdpa_get_vq_num_max,
 	.get_vq_state	= vp_vdpa_get_vq_state,
 	.get_vq_notification = vp_vdpa_get_vq_notification,
diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
index 42c998c82102..5562258f6238 100644
--- a/drivers/vhost/vdpa.c
+++ b/drivers/vhost/vdpa.c
@@ -157,7 +157,7 @@ static long vhost_vdpa_set_status(struct vhost_vdpa *v, u8 __user *statusp)
 	struct vdpa_device *vdpa = v->vdpa;
 	const struct vdpa_config_ops *ops = vdpa->config;
 	u8 status, status_old;
-	int nvqs = v->nvqs;
+	int ret, nvqs = v->nvqs;
 	u16 i;
 
 	if (copy_from_user(&status, statusp, sizeof(status)))
@@ -172,7 +172,12 @@ static long vhost_vdpa_set_status(struct vhost_vdpa *v, u8 __user *statusp)
 	if (status != 0 && (ops->get_status(vdpa) & ~status) != 0)
 		return -EINVAL;
 
-	ops->set_status(vdpa, status);
+	if (status == 0) {
+		ret = ops->reset(vdpa);
+		if (ret)
+			return ret;
+	} else
+		ops->set_status(vdpa, status);
 
 	if ((status & VIRTIO_CONFIG_S_DRIVER_OK) && !(status_old & VIRTIO_CONFIG_S_DRIVER_OK))
 		for (i = 0; i < nvqs; i++)
diff --git a/include/linux/vdpa.h b/include/linux/vdpa.h
index 8ae1134070eb..e1eae8c7483d 100644
--- a/include/linux/vdpa.h
+++ b/include/linux/vdpa.h
@@ -171,6 +171,9 @@ struct vdpa_iova_range {
  * @set_status:			Set the device status
  *				@vdev: vdpa device
  *				@status: virtio device status
+ * @reset:			Reset device
+ *				@vdev: vdpa device
+ *				Returns integer: success (0) or error (< 0)
  * @get_config_size:		Get the size of the configuration space
  *				@vdev: vdpa device
  *				Returns size_t: configuration size
@@ -255,6 +258,7 @@ struct vdpa_config_ops {
 	u32 (*get_vendor_id)(struct vdpa_device *vdev);
 	u8 (*get_status)(struct vdpa_device *vdev);
 	void (*set_status)(struct vdpa_device *vdev, u8 status);
+	int (*reset)(struct vdpa_device *vdev);
 	size_t (*get_config_size)(struct vdpa_device *vdev);
 	void (*get_config)(struct vdpa_device *vdev, unsigned int offset,
 			   void *buf, unsigned int len);
@@ -348,12 +352,12 @@ static inline struct device *vdpa_get_dma_dev(struct vdpa_device *vdev)
 	return vdev->dma_dev;
 }
 
-static inline void vdpa_reset(struct vdpa_device *vdev)
+static inline int vdpa_reset(struct vdpa_device *vdev)
 {
 	const struct vdpa_config_ops *ops = vdev->config;
 
 	vdev->features_valid = false;
-	ops->set_status(vdev, 0);
+	return ops->reset(vdev);
 }
 
 static inline int vdpa_set_features(struct vdpa_device *vdev, u64 features)
-- 
cgit v1.2.3


From c10fb9454adc80c062151c6a436047e1fa59e99f Mon Sep 17 00:00:00 2001
From: Xie Yongji <xieyongji@bytedance.com>
Date: Tue, 31 Aug 2021 18:36:29 +0800
Subject: vdpa: Add an opaque pointer for vdpa_config_ops.dma_map()

Add an opaque pointer for DMA mapping.

Suggested-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20210831103634.33-9-xieyongji@bytedance.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
 drivers/vdpa/vdpa_sim/vdpa_sim.c | 6 +++---
 drivers/vhost/vdpa.c             | 2 +-
 include/linux/vdpa.h             | 2 +-
 3 files changed, 5 insertions(+), 5 deletions(-)

(limited to 'drivers/vdpa')

diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.c b/drivers/vdpa/vdpa_sim/vdpa_sim.c
index f292bb05d6c9..a70fd2a08ff1 100644
--- a/drivers/vdpa/vdpa_sim/vdpa_sim.c
+++ b/drivers/vdpa/vdpa_sim/vdpa_sim.c
@@ -555,14 +555,14 @@ err:
 }
 
 static int vdpasim_dma_map(struct vdpa_device *vdpa, u64 iova, u64 size,
-			   u64 pa, u32 perm)
+			   u64 pa, u32 perm, void *opaque)
 {
 	struct vdpasim *vdpasim = vdpa_to_sim(vdpa);
 	int ret;
 
 	spin_lock(&vdpasim->iommu_lock);
-	ret = vhost_iotlb_add_range(vdpasim->iommu, iova, iova + size - 1, pa,
-				    perm);
+	ret = vhost_iotlb_add_range_ctx(vdpasim->iommu, iova, iova + size - 1,
+					pa, perm, opaque);
 	spin_unlock(&vdpasim->iommu_lock);
 
 	return ret;
diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
index 86fb8d9ce409..5eb2fcc59532 100644
--- a/drivers/vhost/vdpa.c
+++ b/drivers/vhost/vdpa.c
@@ -571,7 +571,7 @@ static int vhost_vdpa_map(struct vhost_vdpa *v,
 		return r;
 
 	if (ops->dma_map) {
-		r = ops->dma_map(vdpa, iova, size, pa, perm);
+		r = ops->dma_map(vdpa, iova, size, pa, perm, NULL);
 	} else if (ops->set_map) {
 		if (!v->in_batch)
 			r = ops->set_map(vdpa, dev->iotlb);
diff --git a/include/linux/vdpa.h b/include/linux/vdpa.h
index e1eae8c7483d..f3014aaca47e 100644
--- a/include/linux/vdpa.h
+++ b/include/linux/vdpa.h
@@ -270,7 +270,7 @@ struct vdpa_config_ops {
 	/* DMA ops */
 	int (*set_map)(struct vdpa_device *vdev, struct vhost_iotlb *iotlb);
 	int (*dma_map)(struct vdpa_device *vdev, u64 iova, u64 size,
-		       u64 pa, u32 perm);
+		       u64 pa, u32 perm, void *opaque);
 	int (*dma_unmap)(struct vdpa_device *vdev, u64 iova, u64 size);
 
 	/* Free device resources */
-- 
cgit v1.2.3


From d8945ec411209272bcd4ae9e75ea1b078257e492 Mon Sep 17 00:00:00 2001
From: Xie Yongji <xieyongji@bytedance.com>
Date: Tue, 31 Aug 2021 18:36:31 +0800
Subject: vdpa: Support transferring virtual addressing during DMA mapping

This patch introduces an attribute for vDPA device to indicate
whether virtual address can be used. If vDPA device driver set
it, vhost-vdpa bus driver will not pin user page and transfer
userspace virtual address instead of physical address during
DMA mapping. And corresponding vma->vm_file and offset will be
also passed as an opaque pointer.

Suggested-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20210831103634.33-11-xieyongji@bytedance.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
 drivers/vdpa/ifcvf/ifcvf_main.c   |  2 +-
 drivers/vdpa/mlx5/net/mlx5_vnet.c |  2 +-
 drivers/vdpa/vdpa.c               |  9 +++-
 drivers/vdpa/vdpa_sim/vdpa_sim.c  |  2 +-
 drivers/vdpa/virtio_pci/vp_vdpa.c |  2 +-
 drivers/vhost/vdpa.c              | 99 ++++++++++++++++++++++++++++++++++-----
 include/linux/vdpa.h              | 20 ++++++--
 7 files changed, 117 insertions(+), 19 deletions(-)

(limited to 'drivers/vdpa')

diff --git a/drivers/vdpa/ifcvf/ifcvf_main.c b/drivers/vdpa/ifcvf/ifcvf_main.c
index 4293481ce910..dcd648e1f7e7 100644
--- a/drivers/vdpa/ifcvf/ifcvf_main.c
+++ b/drivers/vdpa/ifcvf/ifcvf_main.c
@@ -515,7 +515,7 @@ static int ifcvf_vdpa_dev_add(struct vdpa_mgmt_dev *mdev, const char *name)
 	pdev = ifcvf_mgmt_dev->pdev;
 	dev = &pdev->dev;
 	adapter = vdpa_alloc_device(struct ifcvf_adapter, vdpa,
-				    dev, &ifc_vdpa_ops, name);
+				    dev, &ifc_vdpa_ops, name, false);
 	if (IS_ERR(adapter)) {
 		IFCVF_ERR(pdev, "Failed to allocate vDPA structure");
 		return PTR_ERR(adapter);
diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c
index 608f6b900cd9..08f39952fa6a 100644
--- a/drivers/vdpa/mlx5/net/mlx5_vnet.c
+++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c
@@ -2425,7 +2425,7 @@ static int mlx5_vdpa_dev_add(struct vdpa_mgmt_dev *v_mdev, const char *name)
 	max_vqs = min_t(u32, max_vqs, MLX5_MAX_SUPPORTED_VQS);
 
 	ndev = vdpa_alloc_device(struct mlx5_vdpa_net, mvdev.vdev, mdev->device, &mlx5_vdpa_ops,
-				 name);
+				 name, false);
 	if (IS_ERR(ndev))
 		return PTR_ERR(ndev);
 
diff --git a/drivers/vdpa/vdpa.c b/drivers/vdpa/vdpa.c
index bb3f1d1f0422..8f01d6a7ecc5 100644
--- a/drivers/vdpa/vdpa.c
+++ b/drivers/vdpa/vdpa.c
@@ -71,6 +71,7 @@ static void vdpa_release_dev(struct device *d)
  * @config: the bus operations that is supported by this device
  * @size: size of the parent structure that contains private data
  * @name: name of the vdpa device; optional.
+ * @use_va: indicate whether virtual address must be used by this device
  *
  * Driver should use vdpa_alloc_device() wrapper macro instead of
  * using this directly.
@@ -80,7 +81,8 @@ static void vdpa_release_dev(struct device *d)
  */
 struct vdpa_device *__vdpa_alloc_device(struct device *parent,
 					const struct vdpa_config_ops *config,
-					size_t size, const char *name)
+					size_t size, const char *name,
+					bool use_va)
 {
 	struct vdpa_device *vdev;
 	int err = -EINVAL;
@@ -91,6 +93,10 @@ struct vdpa_device *__vdpa_alloc_device(struct device *parent,
 	if (!!config->dma_map != !!config->dma_unmap)
 		goto err;
 
+	/* It should only work for the device that use on-chip IOMMU */
+	if (use_va && !(config->dma_map || config->set_map))
+		goto err;
+
 	err = -ENOMEM;
 	vdev = kzalloc(size, GFP_KERNEL);
 	if (!vdev)
@@ -106,6 +112,7 @@ struct vdpa_device *__vdpa_alloc_device(struct device *parent,
 	vdev->index = err;
 	vdev->config = config;
 	vdev->features_valid = false;
+	vdev->use_va = use_va;
 
 	if (name)
 		err = dev_set_name(&vdev->dev, "%s", name);
diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.c b/drivers/vdpa/vdpa_sim/vdpa_sim.c
index a70fd2a08ff1..5f484fff8dbe 100644
--- a/drivers/vdpa/vdpa_sim/vdpa_sim.c
+++ b/drivers/vdpa/vdpa_sim/vdpa_sim.c
@@ -251,7 +251,7 @@ struct vdpasim *vdpasim_create(struct vdpasim_dev_attr *dev_attr)
 		ops = &vdpasim_config_ops;
 
 	vdpasim = vdpa_alloc_device(struct vdpasim, vdpa, NULL, ops,
-				    dev_attr->name);
+				    dev_attr->name, false);
 	if (IS_ERR(vdpasim)) {
 		ret = PTR_ERR(vdpasim);
 		goto err_alloc;
diff --git a/drivers/vdpa/virtio_pci/vp_vdpa.c b/drivers/vdpa/virtio_pci/vp_vdpa.c
index cd7718b43a6e..5bcd00246d2e 100644
--- a/drivers/vdpa/virtio_pci/vp_vdpa.c
+++ b/drivers/vdpa/virtio_pci/vp_vdpa.c
@@ -446,7 +446,7 @@ static int vp_vdpa_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 		return ret;
 
 	vp_vdpa = vdpa_alloc_device(struct vp_vdpa, vdpa,
-				    dev, &vp_vdpa_ops, NULL);
+				    dev, &vp_vdpa_ops, NULL, false);
 	if (IS_ERR(vp_vdpa)) {
 		dev_err(dev, "vp_vdpa: Failed to allocate vDPA structure\n");
 		return PTR_ERR(vp_vdpa);
diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
index ad50d52d6655..f41d081777f5 100644
--- a/drivers/vhost/vdpa.c
+++ b/drivers/vhost/vdpa.c
@@ -526,8 +526,28 @@ static void vhost_vdpa_pa_unmap(struct vhost_vdpa *v, u64 start, u64 last)
 	}
 }
 
+static void vhost_vdpa_va_unmap(struct vhost_vdpa *v, u64 start, u64 last)
+{
+	struct vhost_dev *dev = &v->vdev;
+	struct vhost_iotlb *iotlb = dev->iotlb;
+	struct vhost_iotlb_map *map;
+	struct vdpa_map_file *map_file;
+
+	while ((map = vhost_iotlb_itree_first(iotlb, start, last)) != NULL) {
+		map_file = (struct vdpa_map_file *)map->opaque;
+		fput(map_file->file);
+		kfree(map_file);
+		vhost_iotlb_map_free(iotlb, map);
+	}
+}
+
 static void vhost_vdpa_iotlb_unmap(struct vhost_vdpa *v, u64 start, u64 last)
 {
+	struct vdpa_device *vdpa = v->vdpa;
+
+	if (vdpa->use_va)
+		return vhost_vdpa_va_unmap(v, start, last);
+
 	return vhost_vdpa_pa_unmap(v, start, last);
 }
 
@@ -562,21 +582,21 @@ static int perm_to_iommu_flags(u32 perm)
 	return flags | IOMMU_CACHE;
 }
 
-static int vhost_vdpa_map(struct vhost_vdpa *v,
-			  u64 iova, u64 size, u64 pa, u32 perm)
+static int vhost_vdpa_map(struct vhost_vdpa *v, u64 iova,
+			  u64 size, u64 pa, u32 perm, void *opaque)
 {
 	struct vhost_dev *dev = &v->vdev;
 	struct vdpa_device *vdpa = v->vdpa;
 	const struct vdpa_config_ops *ops = vdpa->config;
 	int r = 0;
 
-	r = vhost_iotlb_add_range(dev->iotlb, iova, iova + size - 1,
-				  pa, perm);
+	r = vhost_iotlb_add_range_ctx(dev->iotlb, iova, iova + size - 1,
+				      pa, perm, opaque);
 	if (r)
 		return r;
 
 	if (ops->dma_map) {
-		r = ops->dma_map(vdpa, iova, size, pa, perm, NULL);
+		r = ops->dma_map(vdpa, iova, size, pa, perm, opaque);
 	} else if (ops->set_map) {
 		if (!v->in_batch)
 			r = ops->set_map(vdpa, dev->iotlb);
@@ -584,13 +604,15 @@ static int vhost_vdpa_map(struct vhost_vdpa *v,
 		r = iommu_map(v->domain, iova, pa, size,
 			      perm_to_iommu_flags(perm));
 	}
-
-	if (r)
+	if (r) {
 		vhost_iotlb_del_range(dev->iotlb, iova, iova + size - 1);
-	else
+		return r;
+	}
+
+	if (!vdpa->use_va)
 		atomic64_add(PFN_DOWN(size), &dev->mm->pinned_vm);
 
-	return r;
+	return 0;
 }
 
 static void vhost_vdpa_unmap(struct vhost_vdpa *v, u64 iova, u64 size)
@@ -611,6 +633,56 @@ static void vhost_vdpa_unmap(struct vhost_vdpa *v, u64 iova, u64 size)
 	}
 }
 
+static int vhost_vdpa_va_map(struct vhost_vdpa *v,
+			     u64 iova, u64 size, u64 uaddr, u32 perm)
+{
+	struct vhost_dev *dev = &v->vdev;
+	u64 offset, map_size, map_iova = iova;
+	struct vdpa_map_file *map_file;
+	struct vm_area_struct *vma;
+	int ret;
+
+	mmap_read_lock(dev->mm);
+
+	while (size) {
+		vma = find_vma(dev->mm, uaddr);
+		if (!vma) {
+			ret = -EINVAL;
+			break;
+		}
+		map_size = min(size, vma->vm_end - uaddr);
+		if (!(vma->vm_file && (vma->vm_flags & VM_SHARED) &&
+			!(vma->vm_flags & (VM_IO | VM_PFNMAP))))
+			goto next;
+
+		map_file = kzalloc(sizeof(*map_file), GFP_KERNEL);
+		if (!map_file) {
+			ret = -ENOMEM;
+			break;
+		}
+		offset = (vma->vm_pgoff << PAGE_SHIFT) + uaddr - vma->vm_start;
+		map_file->offset = offset;
+		map_file->file = get_file(vma->vm_file);
+		ret = vhost_vdpa_map(v, map_iova, map_size, uaddr,
+				     perm, map_file);
+		if (ret) {
+			fput(map_file->file);
+			kfree(map_file);
+			break;
+		}
+next:
+		size -= map_size;
+		uaddr += map_size;
+		map_iova += map_size;
+	}
+	if (ret)
+		vhost_vdpa_unmap(v, iova, map_iova - iova);
+
+	mmap_read_unlock(dev->mm);
+
+	return ret;
+}
+
 static int vhost_vdpa_pa_map(struct vhost_vdpa *v,
 			     u64 iova, u64 size, u64 uaddr, u32 perm)
 {
@@ -677,7 +749,7 @@ static int vhost_vdpa_pa_map(struct vhost_vdpa *v,
 				csize = PFN_PHYS(last_pfn - map_pfn + 1);
 				ret = vhost_vdpa_map(v, iova, csize,
 						     PFN_PHYS(map_pfn),
-						     perm);
+						     perm, NULL);
 				if (ret) {
 					/*
 					 * Unpin the pages that are left unmapped
@@ -706,7 +778,7 @@ static int vhost_vdpa_pa_map(struct vhost_vdpa *v,
 
 	/* Pin the rest chunk */
 	ret = vhost_vdpa_map(v, iova, PFN_PHYS(last_pfn - map_pfn + 1),
-			     PFN_PHYS(map_pfn), perm);
+			     PFN_PHYS(map_pfn), perm, NULL);
 out:
 	if (ret) {
 		if (nchunks) {
@@ -739,6 +811,7 @@ static int vhost_vdpa_process_iotlb_update(struct vhost_vdpa *v,
 					   struct vhost_iotlb_msg *msg)
 {
 	struct vhost_dev *dev = &v->vdev;
+	struct vdpa_device *vdpa = v->vdpa;
 	struct vhost_iotlb *iotlb = dev->iotlb;
 
 	if (msg->iova < v->range.first || !msg->size ||
@@ -750,6 +823,10 @@ static int vhost_vdpa_process_iotlb_update(struct vhost_vdpa *v,
 				    msg->iova + msg->size - 1))
 		return -EEXIST;
 
+	if (vdpa->use_va)
+		return vhost_vdpa_va_map(v, msg->iova, msg->size,
+					 msg->uaddr, msg->perm);
+
 	return vhost_vdpa_pa_map(v, msg->iova, msg->size, msg->uaddr,
 				 msg->perm);
 }
diff --git a/include/linux/vdpa.h b/include/linux/vdpa.h
index f3014aaca47e..3972ab765de1 100644
--- a/include/linux/vdpa.h
+++ b/include/linux/vdpa.h
@@ -65,6 +65,7 @@ struct vdpa_mgmt_dev;
  * @config: the configuration ops for this device.
  * @index: device index
  * @features_valid: were features initialized? for legacy guests
+ * @use_va: indicate whether virtual address must be used by this device
  * @nvqs: maximum number of supported virtqueues
  * @mdev: management device pointer; caller must setup when registering device as part
  *	  of dev_add() mgmtdev ops callback before invoking _vdpa_register_device().
@@ -75,6 +76,7 @@ struct vdpa_device {
 	const struct vdpa_config_ops *config;
 	unsigned int index;
 	bool features_valid;
+	bool use_va;
 	int nvqs;
 	struct vdpa_mgmt_dev *mdev;
 };
@@ -89,6 +91,16 @@ struct vdpa_iova_range {
 	u64 last;
 };
 
+/**
+ * Corresponding file area for device memory mapping
+ * @file: vma->vm_file for the mapping
+ * @offset: mapping offset in the vm_file
+ */
+struct vdpa_map_file {
+	struct file *file;
+	u64 offset;
+};
+
 /**
  * struct vdpa_config_ops - operations for configuring a vDPA device.
  * Note: vDPA device drivers are required to implement all of the
@@ -279,7 +291,8 @@ struct vdpa_config_ops {
 
 struct vdpa_device *__vdpa_alloc_device(struct device *parent,
 					const struct vdpa_config_ops *config,
-					size_t size, const char *name);
+					size_t size, const char *name,
+					bool use_va);
 
 /**
  * vdpa_alloc_device - allocate and initilaize a vDPA device
@@ -289,15 +302,16 @@ struct vdpa_device *__vdpa_alloc_device(struct device *parent,
  * @parent: the parent device
  * @config: the bus operations that is supported by this device
  * @name: name of the vdpa device
+ * @use_va: indicate whether virtual address must be used by this device
  *
  * Return allocated data structure or ERR_PTR upon error
  */
-#define vdpa_alloc_device(dev_struct, member, parent, config, name)   \
+#define vdpa_alloc_device(dev_struct, member, parent, config, name, use_va)   \
 			  container_of(__vdpa_alloc_device( \
 				       parent, config, \
 				       sizeof(dev_struct) + \
 				       BUILD_BUG_ON_ZERO(offsetof( \
-				       dev_struct, member)), name), \
+				       dev_struct, member)), name, use_va), \
 				       dev_struct, member)
 
 int vdpa_register_device(struct vdpa_device *vdev, int nvqs);
-- 
cgit v1.2.3


From 8c773d53fb7b64267b0f55c1d3517cb8c5e29b3c Mon Sep 17 00:00:00 2001
From: Xie Yongji <xieyongji@bytedance.com>
Date: Tue, 31 Aug 2021 18:36:32 +0800
Subject: vduse: Implement an MMU-based software IOTLB

This implements an MMU-based software IOTLB to support mapping
kernel dma buffer into userspace dynamically. The basic idea
behind it is treating MMU (VA->PA) as IOMMU (IOVA->PA). The
software IOTLB will set up MMU mapping instead of IOMMU mapping
for the DMA transfer so that the userspace process is able to
use its virtual address to access the dma buffer in kernel.

To avoid security issue, a bounce-buffering mechanism is
introduced to prevent userspace accessing the original buffer
directly which may contain other kernel data. During the mapping,
unmapping, the software IOTLB will copy the data from the original
buffer to the bounce buffer and back, depending on the direction
of the transfer. And the bounce-buffer addresses will be mapped
into the user address space instead of the original one.

Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20210831103634.33-12-xieyongji@bytedance.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
 drivers/vdpa/vdpa_user/iova_domain.c | 545 +++++++++++++++++++++++++++++++++++
 drivers/vdpa/vdpa_user/iova_domain.h |  73 +++++
 2 files changed, 618 insertions(+)
 create mode 100644 drivers/vdpa/vdpa_user/iova_domain.c
 create mode 100644 drivers/vdpa/vdpa_user/iova_domain.h

(limited to 'drivers/vdpa')

diff --git a/drivers/vdpa/vdpa_user/iova_domain.c b/drivers/vdpa/vdpa_user/iova_domain.c
new file mode 100644
index 000000000000..1daae2608860
--- /dev/null
+++ b/drivers/vdpa/vdpa_user/iova_domain.c
@@ -0,0 +1,545 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * MMU-based software IOTLB.
+ *
+ * Copyright (C) 2020-2021 Bytedance Inc. and/or its affiliates. All rights reserved.
+ *
+ * Author: Xie Yongji <xieyongji@bytedance.com>
+ *
+ */
+
+#include <linux/slab.h>
+#include <linux/file.h>
+#include <linux/anon_inodes.h>
+#include <linux/highmem.h>
+#include <linux/vmalloc.h>
+#include <linux/vdpa.h>
+
+#include "iova_domain.h"
+
+static int vduse_iotlb_add_range(struct vduse_iova_domain *domain,
+				 u64 start, u64 last,
+				 u64 addr, unsigned int perm,
+				 struct file *file, u64 offset)
+{
+	struct vdpa_map_file *map_file;
+	int ret;
+
+	map_file = kmalloc(sizeof(*map_file), GFP_ATOMIC);
+	if (!map_file)
+		return -ENOMEM;
+
+	map_file->file = get_file(file);
+	map_file->offset = offset;
+
+	ret = vhost_iotlb_add_range_ctx(domain->iotlb, start, last,
+					addr, perm, map_file);
+	if (ret) {
+		fput(map_file->file);
+		kfree(map_file);
+		return ret;
+	}
+	return 0;
+}
+
+static void vduse_iotlb_del_range(struct vduse_iova_domain *domain,
+				  u64 start, u64 last)
+{
+	struct vdpa_map_file *map_file;
+	struct vhost_iotlb_map *map;
+
+	while ((map = vhost_iotlb_itree_first(domain->iotlb, start, last))) {
+		map_file = (struct vdpa_map_file *)map->opaque;
+		fput(map_file->file);
+		kfree(map_file);
+		vhost_iotlb_map_free(domain->iotlb, map);
+	}
+}
+
+int vduse_domain_set_map(struct vduse_iova_domain *domain,
+			 struct vhost_iotlb *iotlb)
+{
+	struct vdpa_map_file *map_file;
+	struct vhost_iotlb_map *map;
+	u64 start = 0ULL, last = ULLONG_MAX;
+	int ret;
+
+	spin_lock(&domain->iotlb_lock);
+	vduse_iotlb_del_range(domain, start, last);
+
+	for (map = vhost_iotlb_itree_first(iotlb, start, last); map;
+	     map = vhost_iotlb_itree_next(map, start, last)) {
+		map_file = (struct vdpa_map_file *)map->opaque;
+		ret = vduse_iotlb_add_range(domain, map->start, map->last,
+					    map->addr, map->perm,
+					    map_file->file,
+					    map_file->offset);
+		if (ret)
+			goto err;
+	}
+	spin_unlock(&domain->iotlb_lock);
+
+	return 0;
+err:
+	vduse_iotlb_del_range(domain, start, last);
+	spin_unlock(&domain->iotlb_lock);
+	return ret;
+}
+
+void vduse_domain_clear_map(struct vduse_iova_domain *domain,
+			    struct vhost_iotlb *iotlb)
+{
+	struct vhost_iotlb_map *map;
+	u64 start = 0ULL, last = ULLONG_MAX;
+
+	spin_lock(&domain->iotlb_lock);
+	for (map = vhost_iotlb_itree_first(iotlb, start, last); map;
+	     map = vhost_iotlb_itree_next(map, start, last)) {
+		vduse_iotlb_del_range(domain, map->start, map->last);
+	}
+	spin_unlock(&domain->iotlb_lock);
+}
+
+static int vduse_domain_map_bounce_page(struct vduse_iova_domain *domain,
+					 u64 iova, u64 size, u64 paddr)
+{
+	struct vduse_bounce_map *map;
+	u64 last = iova + size - 1;
+
+	while (iova <= last) {
+		map = &domain->bounce_maps[iova >> PAGE_SHIFT];
+		if (!map->bounce_page) {
+			map->bounce_page = alloc_page(GFP_ATOMIC);
+			if (!map->bounce_page)
+				return -ENOMEM;
+		}
+		map->orig_phys = paddr;
+		paddr += PAGE_SIZE;
+		iova += PAGE_SIZE;
+	}
+	return 0;
+}
+
+static void vduse_domain_unmap_bounce_page(struct vduse_iova_domain *domain,
+					   u64 iova, u64 size)
+{
+	struct vduse_bounce_map *map;
+	u64 last = iova + size - 1;
+
+	while (iova <= last) {
+		map = &domain->bounce_maps[iova >> PAGE_SHIFT];
+		map->orig_phys = INVALID_PHYS_ADDR;
+		iova += PAGE_SIZE;
+	}
+}
+
+static void do_bounce(phys_addr_t orig, void *addr, size_t size,
+		      enum dma_data_direction dir)
+{
+	unsigned long pfn = PFN_DOWN(orig);
+	unsigned int offset = offset_in_page(orig);
+	char *buffer;
+	unsigned int sz = 0;
+
+	while (size) {
+		sz = min_t(size_t, PAGE_SIZE - offset, size);
+
+		buffer = kmap_atomic(pfn_to_page(pfn));
+		if (dir == DMA_TO_DEVICE)
+			memcpy(addr, buffer + offset, sz);
+		else
+			memcpy(buffer + offset, addr, sz);
+		kunmap_atomic(buffer);
+
+		size -= sz;
+		pfn++;
+		addr += sz;
+		offset = 0;
+	}
+}
+
+static void vduse_domain_bounce(struct vduse_iova_domain *domain,
+				dma_addr_t iova, size_t size,
+				enum dma_data_direction dir)
+{
+	struct vduse_bounce_map *map;
+	unsigned int offset;
+	void *addr;
+	size_t sz;
+
+	if (iova >= domain->bounce_size)
+		return;
+
+	while (size) {
+		map = &domain->bounce_maps[iova >> PAGE_SHIFT];
+		offset = offset_in_page(iova);
+		sz = min_t(size_t, PAGE_SIZE - offset, size);
+
+		if (WARN_ON(!map->bounce_page ||
+			    map->orig_phys == INVALID_PHYS_ADDR))
+			return;
+
+		addr = page_address(map->bounce_page) + offset;
+		do_bounce(map->orig_phys + offset, addr, sz, dir);
+		size -= sz;
+		iova += sz;
+	}
+}
+
+static struct page *
+vduse_domain_get_coherent_page(struct vduse_iova_domain *domain, u64 iova)
+{
+	u64 start = iova & PAGE_MASK;
+	u64 last = start + PAGE_SIZE - 1;
+	struct vhost_iotlb_map *map;
+	struct page *page = NULL;
+
+	spin_lock(&domain->iotlb_lock);
+	map = vhost_iotlb_itree_first(domain->iotlb, start, last);
+	if (!map)
+		goto out;
+
+	page = pfn_to_page((map->addr + iova - map->start) >> PAGE_SHIFT);
+	get_page(page);
+out:
+	spin_unlock(&domain->iotlb_lock);
+
+	return page;
+}
+
+static struct page *
+vduse_domain_get_bounce_page(struct vduse_iova_domain *domain, u64 iova)
+{
+	struct vduse_bounce_map *map;
+	struct page *page = NULL;
+
+	spin_lock(&domain->iotlb_lock);
+	map = &domain->bounce_maps[iova >> PAGE_SHIFT];
+	if (!map->bounce_page)
+		goto out;
+
+	page = map->bounce_page;
+	get_page(page);
+out:
+	spin_unlock(&domain->iotlb_lock);
+
+	return page;
+}
+
+static void
+vduse_domain_free_bounce_pages(struct vduse_iova_domain *domain)
+{
+	struct vduse_bounce_map *map;
+	unsigned long pfn, bounce_pfns;
+
+	bounce_pfns = domain->bounce_size >> PAGE_SHIFT;
+
+	for (pfn = 0; pfn < bounce_pfns; pfn++) {
+		map = &domain->bounce_maps[pfn];
+		if (WARN_ON(map->orig_phys != INVALID_PHYS_ADDR))
+			continue;
+
+		if (!map->bounce_page)
+			continue;
+
+		__free_page(map->bounce_page);
+		map->bounce_page = NULL;
+	}
+}
+
+void vduse_domain_reset_bounce_map(struct vduse_iova_domain *domain)
+{
+	if (!domain->bounce_map)
+		return;
+
+	spin_lock(&domain->iotlb_lock);
+	if (!domain->bounce_map)
+		goto unlock;
+
+	vduse_iotlb_del_range(domain, 0, domain->bounce_size - 1);
+	domain->bounce_map = 0;
+unlock:
+	spin_unlock(&domain->iotlb_lock);
+}
+
+static int vduse_domain_init_bounce_map(struct vduse_iova_domain *domain)
+{
+	int ret = 0;
+
+	if (domain->bounce_map)
+		return 0;
+
+	spin_lock(&domain->iotlb_lock);
+	if (domain->bounce_map)
+		goto unlock;
+
+	ret = vduse_iotlb_add_range(domain, 0, domain->bounce_size - 1,
+				    0, VHOST_MAP_RW, domain->file, 0);
+	if (ret)
+		goto unlock;
+
+	domain->bounce_map = 1;
+unlock:
+	spin_unlock(&domain->iotlb_lock);
+	return ret;
+}
+
+static dma_addr_t
+vduse_domain_alloc_iova(struct iova_domain *iovad,
+			unsigned long size, unsigned long limit)
+{
+	unsigned long shift = iova_shift(iovad);
+	unsigned long iova_len = iova_align(iovad, size) >> shift;
+	unsigned long iova_pfn;
+
+	/*
+	 * Freeing non-power-of-two-sized allocations back into the IOVA caches
+	 * will come back to bite us badly, so we have to waste a bit of space
+	 * rounding up anything cacheable to make sure that can't happen. The
+	 * order of the unadjusted size will still match upon freeing.
+	 */
+	if (iova_len < (1 << (IOVA_RANGE_CACHE_MAX_SIZE - 1)))
+		iova_len = roundup_pow_of_two(iova_len);
+	iova_pfn = alloc_iova_fast(iovad, iova_len, limit >> shift, true);
+
+	return iova_pfn << shift;
+}
+
+static void vduse_domain_free_iova(struct iova_domain *iovad,
+				   dma_addr_t iova, size_t size)
+{
+	unsigned long shift = iova_shift(iovad);
+	unsigned long iova_len = iova_align(iovad, size) >> shift;
+
+	free_iova_fast(iovad, iova >> shift, iova_len);
+}
+
+dma_addr_t vduse_domain_map_page(struct vduse_iova_domain *domain,
+				 struct page *page, unsigned long offset,
+				 size_t size, enum dma_data_direction dir,
+				 unsigned long attrs)
+{
+	struct iova_domain *iovad = &domain->stream_iovad;
+	unsigned long limit = domain->bounce_size - 1;
+	phys_addr_t pa = page_to_phys(page) + offset;
+	dma_addr_t iova = vduse_domain_alloc_iova(iovad, size, limit);
+
+	if (!iova)
+		return DMA_MAPPING_ERROR;
+
+	if (vduse_domain_init_bounce_map(domain))
+		goto err;
+
+	if (vduse_domain_map_bounce_page(domain, (u64)iova, (u64)size, pa))
+		goto err;
+
+	if (dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL)
+		vduse_domain_bounce(domain, iova, size, DMA_TO_DEVICE);
+
+	return iova;
+err:
+	vduse_domain_free_iova(iovad, iova, size);
+	return DMA_MAPPING_ERROR;
+}
+
+void vduse_domain_unmap_page(struct vduse_iova_domain *domain,
+			     dma_addr_t dma_addr, size_t size,
+			     enum dma_data_direction dir, unsigned long attrs)
+{
+	struct iova_domain *iovad = &domain->stream_iovad;
+
+	if (dir == DMA_FROM_DEVICE || dir == DMA_BIDIRECTIONAL)
+		vduse_domain_bounce(domain, dma_addr, size, DMA_FROM_DEVICE);
+
+	vduse_domain_unmap_bounce_page(domain, (u64)dma_addr, (u64)size);
+	vduse_domain_free_iova(iovad, dma_addr, size);
+}
+
+void *vduse_domain_alloc_coherent(struct vduse_iova_domain *domain,
+				  size_t size, dma_addr_t *dma_addr,
+				  gfp_t flag, unsigned long attrs)
+{
+	struct iova_domain *iovad = &domain->consistent_iovad;
+	unsigned long limit = domain->iova_limit;
+	dma_addr_t iova = vduse_domain_alloc_iova(iovad, size, limit);
+	void *orig = alloc_pages_exact(size, flag);
+
+	if (!iova || !orig)
+		goto err;
+
+	spin_lock(&domain->iotlb_lock);
+	if (vduse_iotlb_add_range(domain, (u64)iova, (u64)iova + size - 1,
+				  virt_to_phys(orig), VHOST_MAP_RW,
+				  domain->file, (u64)iova)) {
+		spin_unlock(&domain->iotlb_lock);
+		goto err;
+	}
+	spin_unlock(&domain->iotlb_lock);
+
+	*dma_addr = iova;
+
+	return orig;
+err:
+	*dma_addr = DMA_MAPPING_ERROR;
+	if (orig)
+		free_pages_exact(orig, size);
+	if (iova)
+		vduse_domain_free_iova(iovad, iova, size);
+
+	return NULL;
+}
+
+void vduse_domain_free_coherent(struct vduse_iova_domain *domain, size_t size,
+				void *vaddr, dma_addr_t dma_addr,
+				unsigned long attrs)
+{
+	struct iova_domain *iovad = &domain->consistent_iovad;
+	struct vhost_iotlb_map *map;
+	struct vdpa_map_file *map_file;
+	phys_addr_t pa;
+
+	spin_lock(&domain->iotlb_lock);
+	map = vhost_iotlb_itree_first(domain->iotlb, (u64)dma_addr,
+				      (u64)dma_addr + size - 1);
+	if (WARN_ON(!map)) {
+		spin_unlock(&domain->iotlb_lock);
+		return;
+	}
+	map_file = (struct vdpa_map_file *)map->opaque;
+	fput(map_file->file);
+	kfree(map_file);
+	pa = map->addr;
+	vhost_iotlb_map_free(domain->iotlb, map);
+	spin_unlock(&domain->iotlb_lock);
+
+	vduse_domain_free_iova(iovad, dma_addr, size);
+	free_pages_exact(phys_to_virt(pa), size);
+}
+
+static vm_fault_t vduse_domain_mmap_fault(struct vm_fault *vmf)
+{
+	struct vduse_iova_domain *domain = vmf->vma->vm_private_data;
+	unsigned long iova = vmf->pgoff << PAGE_SHIFT;
+	struct page *page;
+
+	if (!domain)
+		return VM_FAULT_SIGBUS;
+
+	if (iova < domain->bounce_size)
+		page = vduse_domain_get_bounce_page(domain, iova);
+	else
+		page = vduse_domain_get_coherent_page(domain, iova);
+
+	if (!page)
+		return VM_FAULT_SIGBUS;
+
+	vmf->page = page;
+
+	return 0;
+}
+
+static const struct vm_operations_struct vduse_domain_mmap_ops = {
+	.fault = vduse_domain_mmap_fault,
+};
+
+static int vduse_domain_mmap(struct file *file, struct vm_area_struct *vma)
+{
+	struct vduse_iova_domain *domain = file->private_data;
+
+	vma->vm_flags |= VM_DONTDUMP | VM_DONTEXPAND;
+	vma->vm_private_data = domain;
+	vma->vm_ops = &vduse_domain_mmap_ops;
+
+	return 0;
+}
+
+static int vduse_domain_release(struct inode *inode, struct file *file)
+{
+	struct vduse_iova_domain *domain = file->private_data;
+
+	spin_lock(&domain->iotlb_lock);
+	vduse_iotlb_del_range(domain, 0, ULLONG_MAX);
+	vduse_domain_free_bounce_pages(domain);
+	spin_unlock(&domain->iotlb_lock);
+	put_iova_domain(&domain->stream_iovad);
+	put_iova_domain(&domain->consistent_iovad);
+	vhost_iotlb_free(domain->iotlb);
+	vfree(domain->bounce_maps);
+	kfree(domain);
+
+	return 0;
+}
+
+static const struct file_operations vduse_domain_fops = {
+	.owner = THIS_MODULE,
+	.mmap = vduse_domain_mmap,
+	.release = vduse_domain_release,
+};
+
+void vduse_domain_destroy(struct vduse_iova_domain *domain)
+{
+	fput(domain->file);
+}
+
+struct vduse_iova_domain *
+vduse_domain_create(unsigned long iova_limit, size_t bounce_size)
+{
+	struct vduse_iova_domain *domain;
+	struct file *file;
+	struct vduse_bounce_map *map;
+	unsigned long pfn, bounce_pfns;
+
+	bounce_pfns = PAGE_ALIGN(bounce_size) >> PAGE_SHIFT;
+	if (iova_limit <= bounce_size)
+		return NULL;
+
+	domain = kzalloc(sizeof(*domain), GFP_KERNEL);
+	if (!domain)
+		return NULL;
+
+	domain->iotlb = vhost_iotlb_alloc(0, 0);
+	if (!domain->iotlb)
+		goto err_iotlb;
+
+	domain->iova_limit = iova_limit;
+	domain->bounce_size = PAGE_ALIGN(bounce_size);
+	domain->bounce_maps = vzalloc(bounce_pfns *
+				sizeof(struct vduse_bounce_map));
+	if (!domain->bounce_maps)
+		goto err_map;
+
+	for (pfn = 0; pfn < bounce_pfns; pfn++) {
+		map = &domain->bounce_maps[pfn];
+		map->orig_phys = INVALID_PHYS_ADDR;
+	}
+	file = anon_inode_getfile("[vduse-domain]", &vduse_domain_fops,
+				domain, O_RDWR);
+	if (IS_ERR(file))
+		goto err_file;
+
+	domain->file = file;
+	spin_lock_init(&domain->iotlb_lock);
+	init_iova_domain(&domain->stream_iovad,
+			PAGE_SIZE, IOVA_START_PFN);
+	init_iova_domain(&domain->consistent_iovad,
+			PAGE_SIZE, bounce_pfns);
+
+	return domain;
+err_file:
+	vfree(domain->bounce_maps);
+err_map:
+	vhost_iotlb_free(domain->iotlb);
+err_iotlb:
+	kfree(domain);
+	return NULL;
+}
+
+int vduse_domain_init(void)
+{
+	return iova_cache_get();
+}
+
+void vduse_domain_exit(void)
+{
+	iova_cache_put();
+}
diff --git a/drivers/vdpa/vdpa_user/iova_domain.h b/drivers/vdpa/vdpa_user/iova_domain.h
new file mode 100644
index 000000000000..2722d9b8e21a
--- /dev/null
+++ b/drivers/vdpa/vdpa_user/iova_domain.h
@@ -0,0 +1,73 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * MMU-based software IOTLB.
+ *
+ * Copyright (C) 2020-2021 Bytedance Inc. and/or its affiliates. All rights reserved.
+ *
+ * Author: Xie Yongji <xieyongji@bytedance.com>
+ *
+ */
+
+#ifndef _VDUSE_IOVA_DOMAIN_H
+#define _VDUSE_IOVA_DOMAIN_H
+
+#include <linux/iova.h>
+#include <linux/dma-mapping.h>
+#include <linux/vhost_iotlb.h>
+
+#define IOVA_START_PFN 1
+
+#define INVALID_PHYS_ADDR (~(phys_addr_t)0)
+
+struct vduse_bounce_map {
+	struct page *bounce_page;
+	u64 orig_phys;
+};
+
+struct vduse_iova_domain {
+	struct iova_domain stream_iovad;
+	struct iova_domain consistent_iovad;
+	struct vduse_bounce_map *bounce_maps;
+	size_t bounce_size;
+	unsigned long iova_limit;
+	int bounce_map;
+	struct vhost_iotlb *iotlb;
+	spinlock_t iotlb_lock;
+	struct file *file;
+};
+
+int vduse_domain_set_map(struct vduse_iova_domain *domain,
+			 struct vhost_iotlb *iotlb);
+
+void vduse_domain_clear_map(struct vduse_iova_domain *domain,
+			    struct vhost_iotlb *iotlb);
+
+dma_addr_t vduse_domain_map_page(struct vduse_iova_domain *domain,
+				 struct page *page, unsigned long offset,
+				 size_t size, enum dma_data_direction dir,
+				 unsigned long attrs);
+
+void vduse_domain_unmap_page(struct vduse_iova_domain *domain,
+			     dma_addr_t dma_addr, size_t size,
+			     enum dma_data_direction dir, unsigned long attrs);
+
+void *vduse_domain_alloc_coherent(struct vduse_iova_domain *domain,
+				  size_t size, dma_addr_t *dma_addr,
+				  gfp_t flag, unsigned long attrs);
+
+void vduse_domain_free_coherent(struct vduse_iova_domain *domain, size_t size,
+				void *vaddr, dma_addr_t dma_addr,
+				unsigned long attrs);
+
+void vduse_domain_reset_bounce_map(struct vduse_iova_domain *domain);
+
+void vduse_domain_destroy(struct vduse_iova_domain *domain);
+
+struct vduse_iova_domain *vduse_domain_create(unsigned long iova_limit,
+					      size_t bounce_size);
+
+int vduse_domain_init(void);
+
+void vduse_domain_exit(void);
+
+#endif /* _VDUSE_IOVA_DOMAIN_H */
-- 
cgit v1.2.3


From c8a6153b6c59d95c0e091f053f6f180952ade91e Mon Sep 17 00:00:00 2001
From: Xie Yongji <xieyongji@bytedance.com>
Date: Tue, 31 Aug 2021 18:36:33 +0800
Subject: vduse: Introduce VDUSE - vDPA Device in Userspace

This VDUSE driver enables implementing software-emulated vDPA
devices in userspace. The vDPA device is created by
ioctl(VDUSE_CREATE_DEV) on /dev/vduse/control. Then a char device
interface (/dev/vduse/$NAME) is exported to userspace for device
emulation.

In order to make the device emulation more secure, the device's
control path is handled in kernel. A message mechnism is introduced
to forward some dataplane related control messages to userspace.

And in the data path, the DMA buffer will be mapped into userspace
address space through different ways depending on the vDPA bus to
which the vDPA device is attached. In virtio-vdpa case, the MMU-based
software IOTLB is used to achieve that. And in vhost-vdpa case, the
DMA buffer is reside in a userspace memory region which can be shared
to the VDUSE userspace processs via transferring the shmfd.

For more details on VDUSE design and usage, please see the follow-on
Documentation commit.

NB(mst): when merging this with
b542e383d8c0 ("eventfd: Make signal recursion protection a task bit")
replace eventfd_signal_count with eventfd_signal_allowed,
and drop the previous
("eventfd: Export eventfd_wake_count to modules").

Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20210831103634.33-13-xieyongji@bytedance.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
 Documentation/userspace-api/ioctl/ioctl-number.rst |    1 +
 drivers/vdpa/Kconfig                               |   10 +
 drivers/vdpa/Makefile                              |    1 +
 drivers/vdpa/vdpa_user/Makefile                    |    5 +
 drivers/vdpa/vdpa_user/vduse_dev.c                 | 1646 ++++++++++++++++++++
 include/uapi/linux/vduse.h                         |  306 ++++
 6 files changed, 1969 insertions(+)
 create mode 100644 drivers/vdpa/vdpa_user/Makefile
 create mode 100644 drivers/vdpa/vdpa_user/vduse_dev.c
 create mode 100644 include/uapi/linux/vduse.h

(limited to 'drivers/vdpa')

diff --git a/Documentation/userspace-api/ioctl/ioctl-number.rst b/Documentation/userspace-api/ioctl/ioctl-number.rst
index 1409e40e6345..293ca3aef358 100644
--- a/Documentation/userspace-api/ioctl/ioctl-number.rst
+++ b/Documentation/userspace-api/ioctl/ioctl-number.rst
@@ -300,6 +300,7 @@ Code  Seq#    Include File                                           Comments
 'z'   10-4F  drivers/s390/crypto/zcrypt_api.h                        conflict!
 '|'   00-7F  linux/media.h
 0x80  00-1F  linux/fb.h
+0x81  00-1F  linux/vduse.h
 0x89  00-06  arch/x86/include/asm/sockios.h
 0x89  0B-DF  linux/sockios.h
 0x89  E0-EF  linux/sockios.h                                         SIOCPROTOPRIVATE range
diff --git a/drivers/vdpa/Kconfig b/drivers/vdpa/Kconfig
index e48e2b10ca36..3d91982d8371 100644
--- a/drivers/vdpa/Kconfig
+++ b/drivers/vdpa/Kconfig
@@ -33,6 +33,16 @@ config VDPA_SIM_BLOCK
 	  vDPA block device simulator which terminates IO request in a
 	  memory buffer.
 
+config VDPA_USER
+	tristate "VDUSE (vDPA Device in Userspace) support"
+	depends on EVENTFD && MMU && HAS_DMA
+	select DMA_OPS
+	select VHOST_IOTLB
+	select IOMMU_IOVA
+	help
+	  With VDUSE it is possible to emulate a vDPA Device
+	  in a userspace program.
+
 config IFCVF
 	tristate "Intel IFC VF vDPA driver"
 	depends on PCI_MSI
diff --git a/drivers/vdpa/Makefile b/drivers/vdpa/Makefile
index 67fe7f3d6943..f02ebed33f19 100644
--- a/drivers/vdpa/Makefile
+++ b/drivers/vdpa/Makefile
@@ -1,6 +1,7 @@
 # SPDX-License-Identifier: GPL-2.0
 obj-$(CONFIG_VDPA) += vdpa.o
 obj-$(CONFIG_VDPA_SIM) += vdpa_sim/
+obj-$(CONFIG_VDPA_USER) += vdpa_user/
 obj-$(CONFIG_IFCVF)    += ifcvf/
 obj-$(CONFIG_MLX5_VDPA) += mlx5/
 obj-$(CONFIG_VP_VDPA)    += virtio_pci/
diff --git a/drivers/vdpa/vdpa_user/Makefile b/drivers/vdpa/vdpa_user/Makefile
new file mode 100644
index 000000000000..260e0b26af99
--- /dev/null
+++ b/drivers/vdpa/vdpa_user/Makefile
@@ -0,0 +1,5 @@
+# SPDX-License-Identifier: GPL-2.0
+
+vduse-y := vduse_dev.o iova_domain.o
+
+obj-$(CONFIG_VDPA_USER) += vduse.o
diff --git a/drivers/vdpa/vdpa_user/vduse_dev.c b/drivers/vdpa/vdpa_user/vduse_dev.c
new file mode 100644
index 000000000000..b9b2659408e6
--- /dev/null
+++ b/drivers/vdpa/vdpa_user/vduse_dev.c
@@ -0,0 +1,1646 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * VDUSE: vDPA Device in Userspace
+ *
+ * Copyright (C) 2020-2021 Bytedance Inc. and/or its affiliates. All rights reserved.
+ *
+ * Author: Xie Yongji <xieyongji@bytedance.com>
+ *
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/cdev.h>
+#include <linux/device.h>
+#include <linux/eventfd.h>
+#include <linux/slab.h>
+#include <linux/wait.h>
+#include <linux/dma-map-ops.h>
+#include <linux/poll.h>
+#include <linux/file.h>
+#include <linux/uio.h>
+#include <linux/vdpa.h>
+#include <linux/nospec.h>
+#include <uapi/linux/vduse.h>
+#include <uapi/linux/vdpa.h>
+#include <uapi/linux/virtio_config.h>
+#include <uapi/linux/virtio_ids.h>
+#include <uapi/linux/virtio_blk.h>
+#include <linux/mod_devicetable.h>
+
+#include "iova_domain.h"
+
+#define DRV_AUTHOR   "Yongji Xie <xieyongji@bytedance.com>"
+#define DRV_DESC     "vDPA Device in Userspace"
+#define DRV_LICENSE  "GPL v2"
+
+#define VDUSE_DEV_MAX (1U << MINORBITS)
+#define VDUSE_BOUNCE_SIZE (64 * 1024 * 1024)
+#define VDUSE_IOVA_SIZE (128 * 1024 * 1024)
+#define VDUSE_MSG_DEFAULT_TIMEOUT 30
+
+struct vduse_virtqueue {
+	u16 index;
+	u16 num_max;
+	u32 num;
+	u64 desc_addr;
+	u64 driver_addr;
+	u64 device_addr;
+	struct vdpa_vq_state state;
+	bool ready;
+	bool kicked;
+	spinlock_t kick_lock;
+	spinlock_t irq_lock;
+	struct eventfd_ctx *kickfd;
+	struct vdpa_callback cb;
+	struct work_struct inject;
+	struct work_struct kick;
+};
+
+struct vduse_dev;
+
+struct vduse_vdpa {
+	struct vdpa_device vdpa;
+	struct vduse_dev *dev;
+};
+
+struct vduse_dev {
+	struct vduse_vdpa *vdev;
+	struct device *dev;
+	struct vduse_virtqueue *vqs;
+	struct vduse_iova_domain *domain;
+	char *name;
+	struct mutex lock;
+	spinlock_t msg_lock;
+	u64 msg_unique;
+	u32 msg_timeout;
+	wait_queue_head_t waitq;
+	struct list_head send_list;
+	struct list_head recv_list;
+	struct vdpa_callback config_cb;
+	struct work_struct inject;
+	spinlock_t irq_lock;
+	int minor;
+	bool broken;
+	bool connected;
+	u64 api_version;
+	u64 device_features;
+	u64 driver_features;
+	u32 device_id;
+	u32 vendor_id;
+	u32 generation;
+	u32 config_size;
+	void *config;
+	u8 status;
+	u32 vq_num;
+	u32 vq_align;
+};
+
+struct vduse_dev_msg {
+	struct vduse_dev_request req;
+	struct vduse_dev_response resp;
+	struct list_head list;
+	wait_queue_head_t waitq;
+	bool completed;
+};
+
+struct vduse_control {
+	u64 api_version;
+};
+
+static DEFINE_MUTEX(vduse_lock);
+static DEFINE_IDR(vduse_idr);
+
+static dev_t vduse_major;
+static struct class *vduse_class;
+static struct cdev vduse_ctrl_cdev;
+static struct cdev vduse_cdev;
+static struct workqueue_struct *vduse_irq_wq;
+
+static u32 allowed_device_id[] = {
+	VIRTIO_ID_BLOCK,
+};
+
+static inline struct vduse_dev *vdpa_to_vduse(struct vdpa_device *vdpa)
+{
+	struct vduse_vdpa *vdev = container_of(vdpa, struct vduse_vdpa, vdpa);
+
+	return vdev->dev;
+}
+
+static inline struct vduse_dev *dev_to_vduse(struct device *dev)
+{
+	struct vdpa_device *vdpa = dev_to_vdpa(dev);
+
+	return vdpa_to_vduse(vdpa);
+}
+
+static struct vduse_dev_msg *vduse_find_msg(struct list_head *head,
+					    uint32_t request_id)
+{
+	struct vduse_dev_msg *msg;
+
+	list_for_each_entry(msg, head, list) {
+		if (msg->req.request_id == request_id) {
+			list_del(&msg->list);
+			return msg;
+		}
+	}
+
+	return NULL;
+}
+
+static struct vduse_dev_msg *vduse_dequeue_msg(struct list_head *head)
+{
+	struct vduse_dev_msg *msg = NULL;
+
+	if (!list_empty(head)) {
+		msg = list_first_entry(head, struct vduse_dev_msg, list);
+		list_del(&msg->list);
+	}
+
+	return msg;
+}
+
+static void vduse_enqueue_msg(struct list_head *head,
+			      struct vduse_dev_msg *msg)
+{
+	list_add_tail(&msg->list, head);
+}
+
+static void vduse_dev_broken(struct vduse_dev *dev)
+{
+	struct vduse_dev_msg *msg, *tmp;
+
+	if (unlikely(dev->broken))
+		return;
+
+	list_splice_init(&dev->recv_list, &dev->send_list);
+	list_for_each_entry_safe(msg, tmp, &dev->send_list, list) {
+		list_del(&msg->list);
+		msg->completed = 1;
+		msg->resp.result = VDUSE_REQ_RESULT_FAILED;
+		wake_up(&msg->waitq);
+	}
+	dev->broken = true;
+	wake_up(&dev->waitq);
+}
+
+static int vduse_dev_msg_sync(struct vduse_dev *dev,
+			      struct vduse_dev_msg *msg)
+{
+	int ret;
+
+	if (unlikely(dev->broken))
+		return -EIO;
+
+	init_waitqueue_head(&msg->waitq);
+	spin_lock(&dev->msg_lock);
+	if (unlikely(dev->broken)) {
+		spin_unlock(&dev->msg_lock);
+		return -EIO;
+	}
+	msg->req.request_id = dev->msg_unique++;
+	vduse_enqueue_msg(&dev->send_list, msg);
+	wake_up(&dev->waitq);
+	spin_unlock(&dev->msg_lock);
+	if (dev->msg_timeout)
+		ret = wait_event_killable_timeout(msg->waitq, msg->completed,
+						  (long)dev->msg_timeout * HZ);
+	else
+		ret = wait_event_killable(msg->waitq, msg->completed);
+
+	spin_lock(&dev->msg_lock);
+	if (!msg->completed) {
+		list_del(&msg->list);
+		msg->resp.result = VDUSE_REQ_RESULT_FAILED;
+		/* Mark the device as malfunction when there is a timeout */
+		if (!ret)
+			vduse_dev_broken(dev);
+	}
+	ret = (msg->resp.result == VDUSE_REQ_RESULT_OK) ? 0 : -EIO;
+	spin_unlock(&dev->msg_lock);
+
+	return ret;
+}
+
+static int vduse_dev_get_vq_state_packed(struct vduse_dev *dev,
+					 struct vduse_virtqueue *vq,
+					 struct vdpa_vq_state_packed *packed)
+{
+	struct vduse_dev_msg msg = { 0 };
+	int ret;
+
+	msg.req.type = VDUSE_GET_VQ_STATE;
+	msg.req.vq_state.index = vq->index;
+
+	ret = vduse_dev_msg_sync(dev, &msg);
+	if (ret)
+		return ret;
+
+	packed->last_avail_counter =
+			msg.resp.vq_state.packed.last_avail_counter & 0x0001;
+	packed->last_avail_idx =
+			msg.resp.vq_state.packed.last_avail_idx & 0x7FFF;
+	packed->last_used_counter =
+			msg.resp.vq_state.packed.last_used_counter & 0x0001;
+	packed->last_used_idx =
+			msg.resp.vq_state.packed.last_used_idx & 0x7FFF;
+
+	return 0;
+}
+
+static int vduse_dev_get_vq_state_split(struct vduse_dev *dev,
+					struct vduse_virtqueue *vq,
+					struct vdpa_vq_state_split *split)
+{
+	struct vduse_dev_msg msg = { 0 };
+	int ret;
+
+	msg.req.type = VDUSE_GET_VQ_STATE;
+	msg.req.vq_state.index = vq->index;
+
+	ret = vduse_dev_msg_sync(dev, &msg);
+	if (ret)
+		return ret;
+
+	split->avail_index = msg.resp.vq_state.split.avail_index;
+
+	return 0;
+}
+
+static int vduse_dev_set_status(struct vduse_dev *dev, u8 status)
+{
+	struct vduse_dev_msg msg = { 0 };
+
+	msg.req.type = VDUSE_SET_STATUS;
+	msg.req.s.status = status;
+
+	return vduse_dev_msg_sync(dev, &msg);
+}
+
+static int vduse_dev_update_iotlb(struct vduse_dev *dev,
+				  u64 start, u64 last)
+{
+	struct vduse_dev_msg msg = { 0 };
+
+	if (last < start)
+		return -EINVAL;
+
+	msg.req.type = VDUSE_UPDATE_IOTLB;
+	msg.req.iova.start = start;
+	msg.req.iova.last = last;
+
+	return vduse_dev_msg_sync(dev, &msg);
+}
+
+static ssize_t vduse_dev_read_iter(struct kiocb *iocb, struct iov_iter *to)
+{
+	struct file *file = iocb->ki_filp;
+	struct vduse_dev *dev = file->private_data;
+	struct vduse_dev_msg *msg;
+	int size = sizeof(struct vduse_dev_request);
+	ssize_t ret;
+
+	if (iov_iter_count(to) < size)
+		return -EINVAL;
+
+	spin_lock(&dev->msg_lock);
+	while (1) {
+		msg = vduse_dequeue_msg(&dev->send_list);
+		if (msg)
+			break;
+
+		ret = -EAGAIN;
+		if (file->f_flags & O_NONBLOCK)
+			goto unlock;
+
+		spin_unlock(&dev->msg_lock);
+		ret = wait_event_interruptible_exclusive(dev->waitq,
+					!list_empty(&dev->send_list));
+		if (ret)
+			return ret;
+
+		spin_lock(&dev->msg_lock);
+	}
+	spin_unlock(&dev->msg_lock);
+	ret = copy_to_iter(&msg->req, size, to);
+	spin_lock(&dev->msg_lock);
+	if (ret != size) {
+		ret = -EFAULT;
+		vduse_enqueue_msg(&dev->send_list, msg);
+		goto unlock;
+	}
+	vduse_enqueue_msg(&dev->recv_list, msg);
+unlock:
+	spin_unlock(&dev->msg_lock);
+
+	return ret;
+}
+
+static bool is_mem_zero(const char *ptr, int size)
+{
+	int i;
+
+	for (i = 0; i < size; i++) {
+		if (ptr[i])
+			return false;
+	}
+	return true;
+}
+
+static ssize_t vduse_dev_write_iter(struct kiocb *iocb, struct iov_iter *from)
+{
+	struct file *file = iocb->ki_filp;
+	struct vduse_dev *dev = file->private_data;
+	struct vduse_dev_response resp;
+	struct vduse_dev_msg *msg;
+	size_t ret;
+
+	ret = copy_from_iter(&resp, sizeof(resp), from);
+	if (ret != sizeof(resp))
+		return -EINVAL;
+
+	if (!is_mem_zero((const char *)resp.reserved, sizeof(resp.reserved)))
+		return -EINVAL;
+
+	spin_lock(&dev->msg_lock);
+	msg = vduse_find_msg(&dev->recv_list, resp.request_id);
+	if (!msg) {
+		ret = -ENOENT;
+		goto unlock;
+	}
+
+	memcpy(&msg->resp, &resp, sizeof(resp));
+	msg->completed = 1;
+	wake_up(&msg->waitq);
+unlock:
+	spin_unlock(&dev->msg_lock);
+
+	return ret;
+}
+
+static __poll_t vduse_dev_poll(struct file *file, poll_table *wait)
+{
+	struct vduse_dev *dev = file->private_data;
+	__poll_t mask = 0;
+
+	poll_wait(file, &dev->waitq, wait);
+
+	spin_lock(&dev->msg_lock);
+
+	if (unlikely(dev->broken))
+		mask |= EPOLLERR;
+	if (!list_empty(&dev->send_list))
+		mask |= EPOLLIN | EPOLLRDNORM;
+	if (!list_empty(&dev->recv_list))
+		mask |= EPOLLOUT | EPOLLWRNORM;
+
+	spin_unlock(&dev->msg_lock);
+
+	return mask;
+}
+
+static void vduse_dev_reset(struct vduse_dev *dev)
+{
+	int i;
+	struct vduse_iova_domain *domain = dev->domain;
+
+	/* The coherent mappings are handled in vduse_dev_free_coherent() */
+	if (domain->bounce_map)
+		vduse_domain_reset_bounce_map(domain);
+
+	dev->status = 0;
+	dev->driver_features = 0;
+	dev->generation++;
+	spin_lock(&dev->irq_lock);
+	dev->config_cb.callback = NULL;
+	dev->config_cb.private = NULL;
+	spin_unlock(&dev->irq_lock);
+	flush_work(&dev->inject);
+
+	for (i = 0; i < dev->vq_num; i++) {
+		struct vduse_virtqueue *vq = &dev->vqs[i];
+
+		vq->ready = false;
+		vq->desc_addr = 0;
+		vq->driver_addr = 0;
+		vq->device_addr = 0;
+		vq->num = 0;
+		memset(&vq->state, 0, sizeof(vq->state));
+
+		spin_lock(&vq->kick_lock);
+		vq->kicked = false;
+		if (vq->kickfd)
+			eventfd_ctx_put(vq->kickfd);
+		vq->kickfd = NULL;
+		spin_unlock(&vq->kick_lock);
+
+		spin_lock(&vq->irq_lock);
+		vq->cb.callback = NULL;
+		vq->cb.private = NULL;
+		spin_unlock(&vq->irq_lock);
+		flush_work(&vq->inject);
+		flush_work(&vq->kick);
+	}
+}
+
+static int vduse_vdpa_set_vq_address(struct vdpa_device *vdpa, u16 idx,
+				u64 desc_area, u64 driver_area,
+				u64 device_area)
+{
+	struct vduse_dev *dev = vdpa_to_vduse(vdpa);
+	struct vduse_virtqueue *vq = &dev->vqs[idx];
+
+	vq->desc_addr = desc_area;
+	vq->driver_addr = driver_area;
+	vq->device_addr = device_area;
+
+	return 0;
+}
+
+static void vduse_vq_kick(struct vduse_virtqueue *vq)
+{
+	spin_lock(&vq->kick_lock);
+	if (!vq->ready)
+		goto unlock;
+
+	if (vq->kickfd)
+		eventfd_signal(vq->kickfd, 1);
+	else
+		vq->kicked = true;
+unlock:
+	spin_unlock(&vq->kick_lock);
+}
+
+static void vduse_vq_kick_work(struct work_struct *work)
+{
+	struct vduse_virtqueue *vq = container_of(work,
+					struct vduse_virtqueue, kick);
+
+	vduse_vq_kick(vq);
+}
+
+static void vduse_vdpa_kick_vq(struct vdpa_device *vdpa, u16 idx)
+{
+	struct vduse_dev *dev = vdpa_to_vduse(vdpa);
+	struct vduse_virtqueue *vq = &dev->vqs[idx];
+
+	/*
+	 * TODO: after applying b542e383d8c0 ("eventfd: Make signal recursion protection a task bit")
+	 * replace eventfd_signal_count with eventfd_signal_allowed, and
+	 * drop the previous ("eventfd: Export eventfd_wake_count to modules") 
+	 * */
+	if (eventfd_signal_count()) {
+		schedule_work(&vq->kick);
+		return;
+	}
+	vduse_vq_kick(vq);
+}
+
+static void vduse_vdpa_set_vq_cb(struct vdpa_device *vdpa, u16 idx,
+			      struct vdpa_callback *cb)
+{
+	struct vduse_dev *dev = vdpa_to_vduse(vdpa);
+	struct vduse_virtqueue *vq = &dev->vqs[idx];
+
+	spin_lock(&vq->irq_lock);
+	vq->cb.callback = cb->callback;
+	vq->cb.private = cb->private;
+	spin_unlock(&vq->irq_lock);
+}
+
+static void vduse_vdpa_set_vq_num(struct vdpa_device *vdpa, u16 idx, u32 num)
+{
+	struct vduse_dev *dev = vdpa_to_vduse(vdpa);
+	struct vduse_virtqueue *vq = &dev->vqs[idx];
+
+	vq->num = num;
+}
+
+static void vduse_vdpa_set_vq_ready(struct vdpa_device *vdpa,
+					u16 idx, bool ready)
+{
+	struct vduse_dev *dev = vdpa_to_vduse(vdpa);
+	struct vduse_virtqueue *vq = &dev->vqs[idx];
+
+	vq->ready = ready;
+}
+
+static bool vduse_vdpa_get_vq_ready(struct vdpa_device *vdpa, u16 idx)
+{
+	struct vduse_dev *dev = vdpa_to_vduse(vdpa);
+	struct vduse_virtqueue *vq = &dev->vqs[idx];
+
+	return vq->ready;
+}
+
+static int vduse_vdpa_set_vq_state(struct vdpa_device *vdpa, u16 idx,
+				const struct vdpa_vq_state *state)
+{
+	struct vduse_dev *dev = vdpa_to_vduse(vdpa);
+	struct vduse_virtqueue *vq = &dev->vqs[idx];
+
+	if (dev->driver_features & BIT_ULL(VIRTIO_F_RING_PACKED)) {
+		vq->state.packed.last_avail_counter =
+				state->packed.last_avail_counter;
+		vq->state.packed.last_avail_idx = state->packed.last_avail_idx;
+		vq->state.packed.last_used_counter =
+				state->packed.last_used_counter;
+		vq->state.packed.last_used_idx = state->packed.last_used_idx;
+	} else
+		vq->state.split.avail_index = state->split.avail_index;
+
+	return 0;
+}
+
+static int vduse_vdpa_get_vq_state(struct vdpa_device *vdpa, u16 idx,
+				struct vdpa_vq_state *state)
+{
+	struct vduse_dev *dev = vdpa_to_vduse(vdpa);
+	struct vduse_virtqueue *vq = &dev->vqs[idx];
+
+	if (dev->driver_features & BIT_ULL(VIRTIO_F_RING_PACKED))
+		return vduse_dev_get_vq_state_packed(dev, vq, &state->packed);
+
+	return vduse_dev_get_vq_state_split(dev, vq, &state->split);
+}
+
+static u32 vduse_vdpa_get_vq_align(struct vdpa_device *vdpa)
+{
+	struct vduse_dev *dev = vdpa_to_vduse(vdpa);
+
+	return dev->vq_align;
+}
+
+static u64 vduse_vdpa_get_features(struct vdpa_device *vdpa)
+{
+	struct vduse_dev *dev = vdpa_to_vduse(vdpa);
+
+	return dev->device_features;
+}
+
+static int vduse_vdpa_set_features(struct vdpa_device *vdpa, u64 features)
+{
+	struct vduse_dev *dev = vdpa_to_vduse(vdpa);
+
+	dev->driver_features = features;
+	return 0;
+}
+
+static void vduse_vdpa_set_config_cb(struct vdpa_device *vdpa,
+				  struct vdpa_callback *cb)
+{
+	struct vduse_dev *dev = vdpa_to_vduse(vdpa);
+
+	spin_lock(&dev->irq_lock);
+	dev->config_cb.callback = cb->callback;
+	dev->config_cb.private = cb->private;
+	spin_unlock(&dev->irq_lock);
+}
+
+static u16 vduse_vdpa_get_vq_num_max(struct vdpa_device *vdpa)
+{
+	struct vduse_dev *dev = vdpa_to_vduse(vdpa);
+	u16 num_max = 0;
+	int i;
+
+	for (i = 0; i < dev->vq_num; i++)
+		if (num_max < dev->vqs[i].num_max)
+			num_max = dev->vqs[i].num_max;
+
+	return num_max;
+}
+
+static u32 vduse_vdpa_get_device_id(struct vdpa_device *vdpa)
+{
+	struct vduse_dev *dev = vdpa_to_vduse(vdpa);
+
+	return dev->device_id;
+}
+
+static u32 vduse_vdpa_get_vendor_id(struct vdpa_device *vdpa)
+{
+	struct vduse_dev *dev = vdpa_to_vduse(vdpa);
+
+	return dev->vendor_id;
+}
+
+static u8 vduse_vdpa_get_status(struct vdpa_device *vdpa)
+{
+	struct vduse_dev *dev = vdpa_to_vduse(vdpa);
+
+	return dev->status;
+}
+
+static void vduse_vdpa_set_status(struct vdpa_device *vdpa, u8 status)
+{
+	struct vduse_dev *dev = vdpa_to_vduse(vdpa);
+
+	if (vduse_dev_set_status(dev, status))
+		return;
+
+	dev->status = status;
+}
+
+static size_t vduse_vdpa_get_config_size(struct vdpa_device *vdpa)
+{
+	struct vduse_dev *dev = vdpa_to_vduse(vdpa);
+
+	return dev->config_size;
+}
+
+static void vduse_vdpa_get_config(struct vdpa_device *vdpa, unsigned int offset,
+				  void *buf, unsigned int len)
+{
+	struct vduse_dev *dev = vdpa_to_vduse(vdpa);
+
+	if (len > dev->config_size - offset)
+		return;
+
+	memcpy(buf, dev->config + offset, len);
+}
+
+static void vduse_vdpa_set_config(struct vdpa_device *vdpa, unsigned int offset,
+			const void *buf, unsigned int len)
+{
+	/* Now we only support read-only configuration space */
+}
+
+static int vduse_vdpa_reset(struct vdpa_device *vdpa)
+{
+	struct vduse_dev *dev = vdpa_to_vduse(vdpa);
+
+	if (vduse_dev_set_status(dev, 0))
+		return -EIO;
+
+	vduse_dev_reset(dev);
+
+	return 0;
+}
+
+static u32 vduse_vdpa_get_generation(struct vdpa_device *vdpa)
+{
+	struct vduse_dev *dev = vdpa_to_vduse(vdpa);
+
+	return dev->generation;
+}
+
+static int vduse_vdpa_set_map(struct vdpa_device *vdpa,
+				struct vhost_iotlb *iotlb)
+{
+	struct vduse_dev *dev = vdpa_to_vduse(vdpa);
+	int ret;
+
+	ret = vduse_domain_set_map(dev->domain, iotlb);
+	if (ret)
+		return ret;
+
+	ret = vduse_dev_update_iotlb(dev, 0ULL, ULLONG_MAX);
+	if (ret) {
+		vduse_domain_clear_map(dev->domain, iotlb);
+		return ret;
+	}
+
+	return 0;
+}
+
+static void vduse_vdpa_free(struct vdpa_device *vdpa)
+{
+	struct vduse_dev *dev = vdpa_to_vduse(vdpa);
+
+	dev->vdev = NULL;
+}
+
+static const struct vdpa_config_ops vduse_vdpa_config_ops = {
+	.set_vq_address		= vduse_vdpa_set_vq_address,
+	.kick_vq		= vduse_vdpa_kick_vq,
+	.set_vq_cb		= vduse_vdpa_set_vq_cb,
+	.set_vq_num             = vduse_vdpa_set_vq_num,
+	.set_vq_ready		= vduse_vdpa_set_vq_ready,
+	.get_vq_ready		= vduse_vdpa_get_vq_ready,
+	.set_vq_state		= vduse_vdpa_set_vq_state,
+	.get_vq_state		= vduse_vdpa_get_vq_state,
+	.get_vq_align		= vduse_vdpa_get_vq_align,
+	.get_features		= vduse_vdpa_get_features,
+	.set_features		= vduse_vdpa_set_features,
+	.set_config_cb		= vduse_vdpa_set_config_cb,
+	.get_vq_num_max		= vduse_vdpa_get_vq_num_max,
+	.get_device_id		= vduse_vdpa_get_device_id,
+	.get_vendor_id		= vduse_vdpa_get_vendor_id,
+	.get_status		= vduse_vdpa_get_status,
+	.set_status		= vduse_vdpa_set_status,
+	.get_config_size	= vduse_vdpa_get_config_size,
+	.get_config		= vduse_vdpa_get_config,
+	.set_config		= vduse_vdpa_set_config,
+	.get_generation		= vduse_vdpa_get_generation,
+	.reset			= vduse_vdpa_reset,
+	.set_map		= vduse_vdpa_set_map,
+	.free			= vduse_vdpa_free,
+};
+
+static dma_addr_t vduse_dev_map_page(struct device *dev, struct page *page,
+				     unsigned long offset, size_t size,
+				     enum dma_data_direction dir,
+				     unsigned long attrs)
+{
+	struct vduse_dev *vdev = dev_to_vduse(dev);
+	struct vduse_iova_domain *domain = vdev->domain;
+
+	return vduse_domain_map_page(domain, page, offset, size, dir, attrs);
+}
+
+static void vduse_dev_unmap_page(struct device *dev, dma_addr_t dma_addr,
+				size_t size, enum dma_data_direction dir,
+				unsigned long attrs)
+{
+	struct vduse_dev *vdev = dev_to_vduse(dev);
+	struct vduse_iova_domain *domain = vdev->domain;
+
+	return vduse_domain_unmap_page(domain, dma_addr, size, dir, attrs);
+}
+
+static void *vduse_dev_alloc_coherent(struct device *dev, size_t size,
+					dma_addr_t *dma_addr, gfp_t flag,
+					unsigned long attrs)
+{
+	struct vduse_dev *vdev = dev_to_vduse(dev);
+	struct vduse_iova_domain *domain = vdev->domain;
+	unsigned long iova;
+	void *addr;
+
+	*dma_addr = DMA_MAPPING_ERROR;
+	addr = vduse_domain_alloc_coherent(domain, size,
+				(dma_addr_t *)&iova, flag, attrs);
+	if (!addr)
+		return NULL;
+
+	*dma_addr = (dma_addr_t)iova;
+
+	return addr;
+}
+
+static void vduse_dev_free_coherent(struct device *dev, size_t size,
+					void *vaddr, dma_addr_t dma_addr,
+					unsigned long attrs)
+{
+	struct vduse_dev *vdev = dev_to_vduse(dev);
+	struct vduse_iova_domain *domain = vdev->domain;
+
+	vduse_domain_free_coherent(domain, size, vaddr, dma_addr, attrs);
+}
+
+static size_t vduse_dev_max_mapping_size(struct device *dev)
+{
+	struct vduse_dev *vdev = dev_to_vduse(dev);
+	struct vduse_iova_domain *domain = vdev->domain;
+
+	return domain->bounce_size;
+}
+
+static const struct dma_map_ops vduse_dev_dma_ops = {
+	.map_page = vduse_dev_map_page,
+	.unmap_page = vduse_dev_unmap_page,
+	.alloc = vduse_dev_alloc_coherent,
+	.free = vduse_dev_free_coherent,
+	.max_mapping_size = vduse_dev_max_mapping_size,
+};
+
+static unsigned int perm_to_file_flags(u8 perm)
+{
+	unsigned int flags = 0;
+
+	switch (perm) {
+	case VDUSE_ACCESS_WO:
+		flags |= O_WRONLY;
+		break;
+	case VDUSE_ACCESS_RO:
+		flags |= O_RDONLY;
+		break;
+	case VDUSE_ACCESS_RW:
+		flags |= O_RDWR;
+		break;
+	default:
+		WARN(1, "invalidate vhost IOTLB permission\n");
+		break;
+	}
+
+	return flags;
+}
+
+static int vduse_kickfd_setup(struct vduse_dev *dev,
+			struct vduse_vq_eventfd *eventfd)
+{
+	struct eventfd_ctx *ctx = NULL;
+	struct vduse_virtqueue *vq;
+	u32 index;
+
+	if (eventfd->index >= dev->vq_num)
+		return -EINVAL;
+
+	index = array_index_nospec(eventfd->index, dev->vq_num);
+	vq = &dev->vqs[index];
+	if (eventfd->fd >= 0) {
+		ctx = eventfd_ctx_fdget(eventfd->fd);
+		if (IS_ERR(ctx))
+			return PTR_ERR(ctx);
+	} else if (eventfd->fd != VDUSE_EVENTFD_DEASSIGN)
+		return 0;
+
+	spin_lock(&vq->kick_lock);
+	if (vq->kickfd)
+		eventfd_ctx_put(vq->kickfd);
+	vq->kickfd = ctx;
+	if (vq->ready && vq->kicked && vq->kickfd) {
+		eventfd_signal(vq->kickfd, 1);
+		vq->kicked = false;
+	}
+	spin_unlock(&vq->kick_lock);
+
+	return 0;
+}
+
+static bool vduse_dev_is_ready(struct vduse_dev *dev)
+{
+	int i;
+
+	for (i = 0; i < dev->vq_num; i++)
+		if (!dev->vqs[i].num_max)
+			return false;
+
+	return true;
+}
+
+static void vduse_dev_irq_inject(struct work_struct *work)
+{
+	struct vduse_dev *dev = container_of(work, struct vduse_dev, inject);
+
+	spin_lock_irq(&dev->irq_lock);
+	if (dev->config_cb.callback)
+		dev->config_cb.callback(dev->config_cb.private);
+	spin_unlock_irq(&dev->irq_lock);
+}
+
+static void vduse_vq_irq_inject(struct work_struct *work)
+{
+	struct vduse_virtqueue *vq = container_of(work,
+					struct vduse_virtqueue, inject);
+
+	spin_lock_irq(&vq->irq_lock);
+	if (vq->ready && vq->cb.callback)
+		vq->cb.callback(vq->cb.private);
+	spin_unlock_irq(&vq->irq_lock);
+}
+
+static long vduse_dev_ioctl(struct file *file, unsigned int cmd,
+			    unsigned long arg)
+{
+	struct vduse_dev *dev = file->private_data;
+	void __user *argp = (void __user *)arg;
+	int ret;
+
+	if (unlikely(dev->broken))
+		return -EPERM;
+
+	switch (cmd) {
+	case VDUSE_IOTLB_GET_FD: {
+		struct vduse_iotlb_entry entry;
+		struct vhost_iotlb_map *map;
+		struct vdpa_map_file *map_file;
+		struct vduse_iova_domain *domain = dev->domain;
+		struct file *f = NULL;
+
+		ret = -EFAULT;
+		if (copy_from_user(&entry, argp, sizeof(entry)))
+			break;
+
+		ret = -EINVAL;
+		if (entry.start > entry.last)
+			break;
+
+		spin_lock(&domain->iotlb_lock);
+		map = vhost_iotlb_itree_first(domain->iotlb,
+					      entry.start, entry.last);
+		if (map) {
+			map_file = (struct vdpa_map_file *)map->opaque;
+			f = get_file(map_file->file);
+			entry.offset = map_file->offset;
+			entry.start = map->start;
+			entry.last = map->last;
+			entry.perm = map->perm;
+		}
+		spin_unlock(&domain->iotlb_lock);
+		ret = -EINVAL;
+		if (!f)
+			break;
+
+		ret = -EFAULT;
+		if (copy_to_user(argp, &entry, sizeof(entry))) {
+			fput(f);
+			break;
+		}
+		ret = receive_fd(f, perm_to_file_flags(entry.perm));
+		fput(f);
+		break;
+	}
+	case VDUSE_DEV_GET_FEATURES:
+		/*
+		 * Just mirror what driver wrote here.
+		 * The driver is expected to check FEATURE_OK later.
+		 */
+		ret = put_user(dev->driver_features, (u64 __user *)argp);
+		break;
+	case VDUSE_DEV_SET_CONFIG: {
+		struct vduse_config_data config;
+		unsigned long size = offsetof(struct vduse_config_data,
+					      buffer);
+
+		ret = -EFAULT;
+		if (copy_from_user(&config, argp, size))
+			break;
+
+		ret = -EINVAL;
+		if (config.length == 0 ||
+		    config.length > dev->config_size - config.offset)
+			break;
+
+		ret = -EFAULT;
+		if (copy_from_user(dev->config + config.offset, argp + size,
+				   config.length))
+			break;
+
+		ret = 0;
+		break;
+	}
+	case VDUSE_DEV_INJECT_CONFIG_IRQ:
+		ret = 0;
+		queue_work(vduse_irq_wq, &dev->inject);
+		break;
+	case VDUSE_VQ_SETUP: {
+		struct vduse_vq_config config;
+		u32 index;
+
+		ret = -EFAULT;
+		if (copy_from_user(&config, argp, sizeof(config)))
+			break;
+
+		ret = -EINVAL;
+		if (config.index >= dev->vq_num)
+			break;
+
+		if (!is_mem_zero((const char *)config.reserved,
+				 sizeof(config.reserved)))
+			break;
+
+		index = array_index_nospec(config.index, dev->vq_num);
+		dev->vqs[index].num_max = config.max_size;
+		ret = 0;
+		break;
+	}
+	case VDUSE_VQ_GET_INFO: {
+		struct vduse_vq_info vq_info;
+		struct vduse_virtqueue *vq;
+		u32 index;
+
+		ret = -EFAULT;
+		if (copy_from_user(&vq_info, argp, sizeof(vq_info)))
+			break;
+
+		ret = -EINVAL;
+		if (vq_info.index >= dev->vq_num)
+			break;
+
+		index = array_index_nospec(vq_info.index, dev->vq_num);
+		vq = &dev->vqs[index];
+		vq_info.desc_addr = vq->desc_addr;
+		vq_info.driver_addr = vq->driver_addr;
+		vq_info.device_addr = vq->device_addr;
+		vq_info.num = vq->num;
+
+		if (dev->driver_features & BIT_ULL(VIRTIO_F_RING_PACKED)) {
+			vq_info.packed.last_avail_counter =
+				vq->state.packed.last_avail_counter;
+			vq_info.packed.last_avail_idx =
+				vq->state.packed.last_avail_idx;
+			vq_info.packed.last_used_counter =
+				vq->state.packed.last_used_counter;
+			vq_info.packed.last_used_idx =
+				vq->state.packed.last_used_idx;
+		} else
+			vq_info.split.avail_index =
+				vq->state.split.avail_index;
+
+		vq_info.ready = vq->ready;
+
+		ret = -EFAULT;
+		if (copy_to_user(argp, &vq_info, sizeof(vq_info)))
+			break;
+
+		ret = 0;
+		break;
+	}
+	case VDUSE_VQ_SETUP_KICKFD: {
+		struct vduse_vq_eventfd eventfd;
+
+		ret = -EFAULT;
+		if (copy_from_user(&eventfd, argp, sizeof(eventfd)))
+			break;
+
+		ret = vduse_kickfd_setup(dev, &eventfd);
+		break;
+	}
+	case VDUSE_VQ_INJECT_IRQ: {
+		u32 index;
+
+		ret = -EFAULT;
+		if (get_user(index, (u32 __user *)argp))
+			break;
+
+		ret = -EINVAL;
+		if (index >= dev->vq_num)
+			break;
+
+		ret = 0;
+		index = array_index_nospec(index, dev->vq_num);
+		queue_work(vduse_irq_wq, &dev->vqs[index].inject);
+		break;
+	}
+	default:
+		ret = -ENOIOCTLCMD;
+		break;
+	}
+
+	return ret;
+}
+
+static int vduse_dev_release(struct inode *inode, struct file *file)
+{
+	struct vduse_dev *dev = file->private_data;
+
+	spin_lock(&dev->msg_lock);
+	/* Make sure the inflight messages can processed after reconncection */
+	list_splice_init(&dev->recv_list, &dev->send_list);
+	spin_unlock(&dev->msg_lock);
+	dev->connected = false;
+
+	return 0;
+}
+
+static struct vduse_dev *vduse_dev_get_from_minor(int minor)
+{
+	struct vduse_dev *dev;
+
+	mutex_lock(&vduse_lock);
+	dev = idr_find(&vduse_idr, minor);
+	mutex_unlock(&vduse_lock);
+
+	return dev;
+}
+
+static int vduse_dev_open(struct inode *inode, struct file *file)
+{
+	int ret;
+	struct vduse_dev *dev = vduse_dev_get_from_minor(iminor(inode));
+
+	if (!dev)
+		return -ENODEV;
+
+	ret = -EBUSY;
+	mutex_lock(&dev->lock);
+	if (dev->connected)
+		goto unlock;
+
+	ret = 0;
+	dev->connected = true;
+	file->private_data = dev;
+unlock:
+	mutex_unlock(&dev->lock);
+
+	return ret;
+}
+
+static const struct file_operations vduse_dev_fops = {
+	.owner		= THIS_MODULE,
+	.open		= vduse_dev_open,
+	.release	= vduse_dev_release,
+	.read_iter	= vduse_dev_read_iter,
+	.write_iter	= vduse_dev_write_iter,
+	.poll		= vduse_dev_poll,
+	.unlocked_ioctl	= vduse_dev_ioctl,
+	.compat_ioctl	= compat_ptr_ioctl,
+	.llseek		= noop_llseek,
+};
+
+static struct vduse_dev *vduse_dev_create(void)
+{
+	struct vduse_dev *dev = kzalloc(sizeof(*dev), GFP_KERNEL);
+
+	if (!dev)
+		return NULL;
+
+	mutex_init(&dev->lock);
+	spin_lock_init(&dev->msg_lock);
+	INIT_LIST_HEAD(&dev->send_list);
+	INIT_LIST_HEAD(&dev->recv_list);
+	spin_lock_init(&dev->irq_lock);
+
+	INIT_WORK(&dev->inject, vduse_dev_irq_inject);
+	init_waitqueue_head(&dev->waitq);
+
+	return dev;
+}
+
+static void vduse_dev_destroy(struct vduse_dev *dev)
+{
+	kfree(dev);
+}
+
+static struct vduse_dev *vduse_find_dev(const char *name)
+{
+	struct vduse_dev *dev;
+	int id;
+
+	idr_for_each_entry(&vduse_idr, dev, id)
+		if (!strcmp(dev->name, name))
+			return dev;
+
+	return NULL;
+}
+
+static int vduse_destroy_dev(char *name)
+{
+	struct vduse_dev *dev = vduse_find_dev(name);
+
+	if (!dev)
+		return -EINVAL;
+
+	mutex_lock(&dev->lock);
+	if (dev->vdev || dev->connected) {
+		mutex_unlock(&dev->lock);
+		return -EBUSY;
+	}
+	dev->connected = true;
+	mutex_unlock(&dev->lock);
+
+	vduse_dev_reset(dev);
+	device_destroy(vduse_class, MKDEV(MAJOR(vduse_major), dev->minor));
+	idr_remove(&vduse_idr, dev->minor);
+	kvfree(dev->config);
+	kfree(dev->vqs);
+	vduse_domain_destroy(dev->domain);
+	kfree(dev->name);
+	vduse_dev_destroy(dev);
+	module_put(THIS_MODULE);
+
+	return 0;
+}
+
+static bool device_is_allowed(u32 device_id)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(allowed_device_id); i++)
+		if (allowed_device_id[i] == device_id)
+			return true;
+
+	return false;
+}
+
+static bool features_is_valid(u64 features)
+{
+	if (!(features & (1ULL << VIRTIO_F_ACCESS_PLATFORM)))
+		return false;
+
+	/* Now we only support read-only configuration space */
+	if (features & (1ULL << VIRTIO_BLK_F_CONFIG_WCE))
+		return false;
+
+	return true;
+}
+
+static bool vduse_validate_config(struct vduse_dev_config *config)
+{
+	if (!is_mem_zero((const char *)config->reserved,
+			 sizeof(config->reserved)))
+		return false;
+
+	if (config->vq_align > PAGE_SIZE)
+		return false;
+
+	if (config->config_size > PAGE_SIZE)
+		return false;
+
+	if (!device_is_allowed(config->device_id))
+		return false;
+
+	if (!features_is_valid(config->features))
+		return false;
+
+	return true;
+}
+
+static ssize_t msg_timeout_show(struct device *device,
+				struct device_attribute *attr, char *buf)
+{
+	struct vduse_dev *dev = dev_get_drvdata(device);
+
+	return sysfs_emit(buf, "%u\n", dev->msg_timeout);
+}
+
+static ssize_t msg_timeout_store(struct device *device,
+				 struct device_attribute *attr,
+				 const char *buf, size_t count)
+{
+	struct vduse_dev *dev = dev_get_drvdata(device);
+	int ret;
+
+	ret = kstrtouint(buf, 10, &dev->msg_timeout);
+	if (ret < 0)
+		return ret;
+
+	return count;
+}
+
+static DEVICE_ATTR_RW(msg_timeout);
+
+static struct attribute *vduse_dev_attrs[] = {
+	&dev_attr_msg_timeout.attr,
+	NULL
+};
+
+ATTRIBUTE_GROUPS(vduse_dev);
+
+static int vduse_create_dev(struct vduse_dev_config *config,
+			    void *config_buf, u64 api_version)
+{
+	int i, ret;
+	struct vduse_dev *dev;
+
+	ret = -EEXIST;
+	if (vduse_find_dev(config->name))
+		goto err;
+
+	ret = -ENOMEM;
+	dev = vduse_dev_create();
+	if (!dev)
+		goto err;
+
+	dev->api_version = api_version;
+	dev->device_features = config->features;
+	dev->device_id = config->device_id;
+	dev->vendor_id = config->vendor_id;
+	dev->name = kstrdup(config->name, GFP_KERNEL);
+	if (!dev->name)
+		goto err_str;
+
+	dev->domain = vduse_domain_create(VDUSE_IOVA_SIZE - 1,
+					  VDUSE_BOUNCE_SIZE);
+	if (!dev->domain)
+		goto err_domain;
+
+	dev->config = config_buf;
+	dev->config_size = config->config_size;
+	dev->vq_align = config->vq_align;
+	dev->vq_num = config->vq_num;
+	dev->vqs = kcalloc(dev->vq_num, sizeof(*dev->vqs), GFP_KERNEL);
+	if (!dev->vqs)
+		goto err_vqs;
+
+	for (i = 0; i < dev->vq_num; i++) {
+		dev->vqs[i].index = i;
+		INIT_WORK(&dev->vqs[i].inject, vduse_vq_irq_inject);
+		INIT_WORK(&dev->vqs[i].kick, vduse_vq_kick_work);
+		spin_lock_init(&dev->vqs[i].kick_lock);
+		spin_lock_init(&dev->vqs[i].irq_lock);
+	}
+
+	ret = idr_alloc(&vduse_idr, dev, 1, VDUSE_DEV_MAX, GFP_KERNEL);
+	if (ret < 0)
+		goto err_idr;
+
+	dev->minor = ret;
+	dev->msg_timeout = VDUSE_MSG_DEFAULT_TIMEOUT;
+	dev->dev = device_create(vduse_class, NULL,
+				 MKDEV(MAJOR(vduse_major), dev->minor),
+				 dev, "%s", config->name);
+	if (IS_ERR(dev->dev)) {
+		ret = PTR_ERR(dev->dev);
+		goto err_dev;
+	}
+	__module_get(THIS_MODULE);
+
+	return 0;
+err_dev:
+	idr_remove(&vduse_idr, dev->minor);
+err_idr:
+	kfree(dev->vqs);
+err_vqs:
+	vduse_domain_destroy(dev->domain);
+err_domain:
+	kfree(dev->name);
+err_str:
+	vduse_dev_destroy(dev);
+err:
+	kvfree(config_buf);
+	return ret;
+}
+
+static long vduse_ioctl(struct file *file, unsigned int cmd,
+			unsigned long arg)
+{
+	int ret;
+	void __user *argp = (void __user *)arg;
+	struct vduse_control *control = file->private_data;
+
+	mutex_lock(&vduse_lock);
+	switch (cmd) {
+	case VDUSE_GET_API_VERSION:
+		ret = put_user(control->api_version, (u64 __user *)argp);
+		break;
+	case VDUSE_SET_API_VERSION: {
+		u64 api_version;
+
+		ret = -EFAULT;
+		if (get_user(api_version, (u64 __user *)argp))
+			break;
+
+		ret = -EINVAL;
+		if (api_version > VDUSE_API_VERSION)
+			break;
+
+		ret = 0;
+		control->api_version = api_version;
+		break;
+	}
+	case VDUSE_CREATE_DEV: {
+		struct vduse_dev_config config;
+		unsigned long size = offsetof(struct vduse_dev_config, config);
+		void *buf;
+
+		ret = -EFAULT;
+		if (copy_from_user(&config, argp, size))
+			break;
+
+		ret = -EINVAL;
+		if (vduse_validate_config(&config) == false)
+			break;
+
+		buf = vmemdup_user(argp + size, config.config_size);
+		if (IS_ERR(buf)) {
+			ret = PTR_ERR(buf);
+			break;
+		}
+		config.name[VDUSE_NAME_MAX - 1] = '\0';
+		ret = vduse_create_dev(&config, buf, control->api_version);
+		break;
+	}
+	case VDUSE_DESTROY_DEV: {
+		char name[VDUSE_NAME_MAX];
+
+		ret = -EFAULT;
+		if (copy_from_user(name, argp, VDUSE_NAME_MAX))
+			break;
+
+		name[VDUSE_NAME_MAX - 1] = '\0';
+		ret = vduse_destroy_dev(name);
+		break;
+	}
+	default:
+		ret = -EINVAL;
+		break;
+	}
+	mutex_unlock(&vduse_lock);
+
+	return ret;
+}
+
+static int vduse_release(struct inode *inode, struct file *file)
+{
+	struct vduse_control *control = file->private_data;
+
+	kfree(control);
+	return 0;
+}
+
+static int vduse_open(struct inode *inode, struct file *file)
+{
+	struct vduse_control *control;
+
+	control = kmalloc(sizeof(struct vduse_control), GFP_KERNEL);
+	if (!control)
+		return -ENOMEM;
+
+	control->api_version = VDUSE_API_VERSION;
+	file->private_data = control;
+
+	return 0;
+}
+
+static const struct file_operations vduse_ctrl_fops = {
+	.owner		= THIS_MODULE,
+	.open		= vduse_open,
+	.release	= vduse_release,
+	.unlocked_ioctl	= vduse_ioctl,
+	.compat_ioctl	= compat_ptr_ioctl,
+	.llseek		= noop_llseek,
+};
+
+static char *vduse_devnode(struct device *dev, umode_t *mode)
+{
+	return kasprintf(GFP_KERNEL, "vduse/%s", dev_name(dev));
+}
+
+static void vduse_mgmtdev_release(struct device *dev)
+{
+}
+
+static struct device vduse_mgmtdev = {
+	.init_name = "vduse",
+	.release = vduse_mgmtdev_release,
+};
+
+static struct vdpa_mgmt_dev mgmt_dev;
+
+static int vduse_dev_init_vdpa(struct vduse_dev *dev, const char *name)
+{
+	struct vduse_vdpa *vdev;
+	int ret;
+
+	if (dev->vdev)
+		return -EEXIST;
+
+	vdev = vdpa_alloc_device(struct vduse_vdpa, vdpa, dev->dev,
+				 &vduse_vdpa_config_ops, name, true);
+	if (IS_ERR(vdev))
+		return PTR_ERR(vdev);
+
+	dev->vdev = vdev;
+	vdev->dev = dev;
+	vdev->vdpa.dev.dma_mask = &vdev->vdpa.dev.coherent_dma_mask;
+	ret = dma_set_mask_and_coherent(&vdev->vdpa.dev, DMA_BIT_MASK(64));
+	if (ret) {
+		put_device(&vdev->vdpa.dev);
+		return ret;
+	}
+	set_dma_ops(&vdev->vdpa.dev, &vduse_dev_dma_ops);
+	vdev->vdpa.dma_dev = &vdev->vdpa.dev;
+	vdev->vdpa.mdev = &mgmt_dev;
+
+	return 0;
+}
+
+static int vdpa_dev_add(struct vdpa_mgmt_dev *mdev, const char *name)
+{
+	struct vduse_dev *dev;
+	int ret;
+
+	mutex_lock(&vduse_lock);
+	dev = vduse_find_dev(name);
+	if (!dev || !vduse_dev_is_ready(dev)) {
+		mutex_unlock(&vduse_lock);
+		return -EINVAL;
+	}
+	ret = vduse_dev_init_vdpa(dev, name);
+	mutex_unlock(&vduse_lock);
+	if (ret)
+		return ret;
+
+	ret = _vdpa_register_device(&dev->vdev->vdpa, dev->vq_num);
+	if (ret) {
+		put_device(&dev->vdev->vdpa.dev);
+		return ret;
+	}
+
+	return 0;
+}
+
+static void vdpa_dev_del(struct vdpa_mgmt_dev *mdev, struct vdpa_device *dev)
+{
+	_vdpa_unregister_device(dev);
+}
+
+static const struct vdpa_mgmtdev_ops vdpa_dev_mgmtdev_ops = {
+	.dev_add = vdpa_dev_add,
+	.dev_del = vdpa_dev_del,
+};
+
+static struct virtio_device_id id_table[] = {
+	{ VIRTIO_ID_BLOCK, VIRTIO_DEV_ANY_ID },
+	{ 0 },
+};
+
+static struct vdpa_mgmt_dev mgmt_dev = {
+	.device = &vduse_mgmtdev,
+	.id_table = id_table,
+	.ops = &vdpa_dev_mgmtdev_ops,
+};
+
+static int vduse_mgmtdev_init(void)
+{
+	int ret;
+
+	ret = device_register(&vduse_mgmtdev);
+	if (ret)
+		return ret;
+
+	ret = vdpa_mgmtdev_register(&mgmt_dev);
+	if (ret)
+		goto err;
+
+	return 0;
+err:
+	device_unregister(&vduse_mgmtdev);
+	return ret;
+}
+
+static void vduse_mgmtdev_exit(void)
+{
+	vdpa_mgmtdev_unregister(&mgmt_dev);
+	device_unregister(&vduse_mgmtdev);
+}
+
+static int vduse_init(void)
+{
+	int ret;
+	struct device *dev;
+
+	vduse_class = class_create(THIS_MODULE, "vduse");
+	if (IS_ERR(vduse_class))
+		return PTR_ERR(vduse_class);
+
+	vduse_class->devnode = vduse_devnode;
+	vduse_class->dev_groups = vduse_dev_groups;
+
+	ret = alloc_chrdev_region(&vduse_major, 0, VDUSE_DEV_MAX, "vduse");
+	if (ret)
+		goto err_chardev_region;
+
+	/* /dev/vduse/control */
+	cdev_init(&vduse_ctrl_cdev, &vduse_ctrl_fops);
+	vduse_ctrl_cdev.owner = THIS_MODULE;
+	ret = cdev_add(&vduse_ctrl_cdev, vduse_major, 1);
+	if (ret)
+		goto err_ctrl_cdev;
+
+	dev = device_create(vduse_class, NULL, vduse_major, NULL, "control");
+	if (IS_ERR(dev)) {
+		ret = PTR_ERR(dev);
+		goto err_device;
+	}
+
+	/* /dev/vduse/$DEVICE */
+	cdev_init(&vduse_cdev, &vduse_dev_fops);
+	vduse_cdev.owner = THIS_MODULE;
+	ret = cdev_add(&vduse_cdev, MKDEV(MAJOR(vduse_major), 1),
+		       VDUSE_DEV_MAX - 1);
+	if (ret)
+		goto err_cdev;
+
+	vduse_irq_wq = alloc_workqueue("vduse-irq",
+				WQ_HIGHPRI | WQ_SYSFS | WQ_UNBOUND, 0);
+	if (!vduse_irq_wq)
+		goto err_wq;
+
+	ret = vduse_domain_init();
+	if (ret)
+		goto err_domain;
+
+	ret = vduse_mgmtdev_init();
+	if (ret)
+		goto err_mgmtdev;
+
+	return 0;
+err_mgmtdev:
+	vduse_domain_exit();
+err_domain:
+	destroy_workqueue(vduse_irq_wq);
+err_wq:
+	cdev_del(&vduse_cdev);
+err_cdev:
+	device_destroy(vduse_class, vduse_major);
+err_device:
+	cdev_del(&vduse_ctrl_cdev);
+err_ctrl_cdev:
+	unregister_chrdev_region(vduse_major, VDUSE_DEV_MAX);
+err_chardev_region:
+	class_destroy(vduse_class);
+	return ret;
+}
+module_init(vduse_init);
+
+static void vduse_exit(void)
+{
+	vduse_mgmtdev_exit();
+	vduse_domain_exit();
+	destroy_workqueue(vduse_irq_wq);
+	cdev_del(&vduse_cdev);
+	device_destroy(vduse_class, vduse_major);
+	cdev_del(&vduse_ctrl_cdev);
+	unregister_chrdev_region(vduse_major, VDUSE_DEV_MAX);
+	class_destroy(vduse_class);
+}
+module_exit(vduse_exit);
+
+MODULE_LICENSE(DRV_LICENSE);
+MODULE_AUTHOR(DRV_AUTHOR);
+MODULE_DESCRIPTION(DRV_DESC);
diff --git a/include/uapi/linux/vduse.h b/include/uapi/linux/vduse.h
new file mode 100644
index 000000000000..7cfe1c1280c0
--- /dev/null
+++ b/include/uapi/linux/vduse.h
@@ -0,0 +1,306 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+#ifndef _UAPI_VDUSE_H_
+#define _UAPI_VDUSE_H_
+
+#include <linux/types.h>
+
+#define VDUSE_BASE	0x81
+
+/* The ioctls for control device (/dev/vduse/control) */
+
+#define VDUSE_API_VERSION	0
+
+/*
+ * Get the version of VDUSE API that kernel supported (VDUSE_API_VERSION).
+ * This is used for future extension.
+ */
+#define VDUSE_GET_API_VERSION	_IOR(VDUSE_BASE, 0x00, __u64)
+
+/* Set the version of VDUSE API that userspace supported. */
+#define VDUSE_SET_API_VERSION	_IOW(VDUSE_BASE, 0x01, __u64)
+
+/**
+ * struct vduse_dev_config - basic configuration of a VDUSE device
+ * @name: VDUSE device name, needs to be NUL terminated
+ * @vendor_id: virtio vendor id
+ * @device_id: virtio device id
+ * @features: virtio features
+ * @vq_num: the number of virtqueues
+ * @vq_align: the allocation alignment of virtqueue's metadata
+ * @reserved: for future use, needs to be initialized to zero
+ * @config_size: the size of the configuration space
+ * @config: the buffer of the configuration space
+ *
+ * Structure used by VDUSE_CREATE_DEV ioctl to create VDUSE device.
+ */
+struct vduse_dev_config {
+#define VDUSE_NAME_MAX	256
+	char name[VDUSE_NAME_MAX];
+	__u32 vendor_id;
+	__u32 device_id;
+	__u64 features;
+	__u32 vq_num;
+	__u32 vq_align;
+	__u32 reserved[13];
+	__u32 config_size;
+	__u8 config[];
+};
+
+/* Create a VDUSE device which is represented by a char device (/dev/vduse/$NAME) */
+#define VDUSE_CREATE_DEV	_IOW(VDUSE_BASE, 0x02, struct vduse_dev_config)
+
+/*
+ * Destroy a VDUSE device. Make sure there are no more references
+ * to the char device (/dev/vduse/$NAME).
+ */
+#define VDUSE_DESTROY_DEV	_IOW(VDUSE_BASE, 0x03, char[VDUSE_NAME_MAX])
+
+/* The ioctls for VDUSE device (/dev/vduse/$NAME) */
+
+/**
+ * struct vduse_iotlb_entry - entry of IOTLB to describe one IOVA region [start, last]
+ * @offset: the mmap offset on returned file descriptor
+ * @start: start of the IOVA region
+ * @last: last of the IOVA region
+ * @perm: access permission of the IOVA region
+ *
+ * Structure used by VDUSE_IOTLB_GET_FD ioctl to find an overlapped IOVA region.
+ */
+struct vduse_iotlb_entry {
+	__u64 offset;
+	__u64 start;
+	__u64 last;
+#define VDUSE_ACCESS_RO 0x1
+#define VDUSE_ACCESS_WO 0x2
+#define VDUSE_ACCESS_RW 0x3
+	__u8 perm;
+};
+
+/*
+ * Find the first IOVA region that overlaps with the range [start, last]
+ * and return the corresponding file descriptor. Return -EINVAL means the
+ * IOVA region doesn't exist. Caller should set start and last fields.
+ */
+#define VDUSE_IOTLB_GET_FD	_IOWR(VDUSE_BASE, 0x10, struct vduse_iotlb_entry)
+
+/*
+ * Get the negotiated virtio features. It's a subset of the features in
+ * struct vduse_dev_config which can be accepted by virtio driver. It's
+ * only valid after FEATURES_OK status bit is set.
+ */
+#define VDUSE_DEV_GET_FEATURES	_IOR(VDUSE_BASE, 0x11, __u64)
+
+/**
+ * struct vduse_config_data - data used to update configuration space
+ * @offset: the offset from the beginning of configuration space
+ * @length: the length to write to configuration space
+ * @buffer: the buffer used to write from
+ *
+ * Structure used by VDUSE_DEV_SET_CONFIG ioctl to update device
+ * configuration space.
+ */
+struct vduse_config_data {
+	__u32 offset;
+	__u32 length;
+	__u8 buffer[];
+};
+
+/* Set device configuration space */
+#define VDUSE_DEV_SET_CONFIG	_IOW(VDUSE_BASE, 0x12, struct vduse_config_data)
+
+/*
+ * Inject a config interrupt. It's usually used to notify virtio driver
+ * that device configuration space has changed.
+ */
+#define VDUSE_DEV_INJECT_CONFIG_IRQ	_IO(VDUSE_BASE, 0x13)
+
+/**
+ * struct vduse_vq_config - basic configuration of a virtqueue
+ * @index: virtqueue index
+ * @max_size: the max size of virtqueue
+ * @reserved: for future use, needs to be initialized to zero
+ *
+ * Structure used by VDUSE_VQ_SETUP ioctl to setup a virtqueue.
+ */
+struct vduse_vq_config {
+	__u32 index;
+	__u16 max_size;
+	__u16 reserved[13];
+};
+
+/*
+ * Setup the specified virtqueue. Make sure all virtqueues have been
+ * configured before the device is attached to vDPA bus.
+ */
+#define VDUSE_VQ_SETUP		_IOW(VDUSE_BASE, 0x14, struct vduse_vq_config)
+
+/**
+ * struct vduse_vq_state_split - split virtqueue state
+ * @avail_index: available index
+ */
+struct vduse_vq_state_split {
+	__u16 avail_index;
+};
+
+/**
+ * struct vduse_vq_state_packed - packed virtqueue state
+ * @last_avail_counter: last driver ring wrap counter observed by device
+ * @last_avail_idx: device available index
+ * @last_used_counter: device ring wrap counter
+ * @last_used_idx: used index
+ */
+struct vduse_vq_state_packed {
+	__u16 last_avail_counter;
+	__u16 last_avail_idx;
+	__u16 last_used_counter;
+	__u16 last_used_idx;
+};
+
+/**
+ * struct vduse_vq_info - information of a virtqueue
+ * @index: virtqueue index
+ * @num: the size of virtqueue
+ * @desc_addr: address of desc area
+ * @driver_addr: address of driver area
+ * @device_addr: address of device area
+ * @split: split virtqueue state
+ * @packed: packed virtqueue state
+ * @ready: ready status of virtqueue
+ *
+ * Structure used by VDUSE_VQ_GET_INFO ioctl to get virtqueue's information.
+ */
+struct vduse_vq_info {
+	__u32 index;
+	__u32 num;
+	__u64 desc_addr;
+	__u64 driver_addr;
+	__u64 device_addr;
+	union {
+		struct vduse_vq_state_split split;
+		struct vduse_vq_state_packed packed;
+	};
+	__u8 ready;
+};
+
+/* Get the specified virtqueue's information. Caller should set index field. */
+#define VDUSE_VQ_GET_INFO	_IOWR(VDUSE_BASE, 0x15, struct vduse_vq_info)
+
+/**
+ * struct vduse_vq_eventfd - eventfd configuration for a virtqueue
+ * @index: virtqueue index
+ * @fd: eventfd, -1 means de-assigning the eventfd
+ *
+ * Structure used by VDUSE_VQ_SETUP_KICKFD ioctl to setup kick eventfd.
+ */
+struct vduse_vq_eventfd {
+	__u32 index;
+#define VDUSE_EVENTFD_DEASSIGN -1
+	int fd;
+};
+
+/*
+ * Setup kick eventfd for specified virtqueue. The kick eventfd is used
+ * by VDUSE kernel module to notify userspace to consume the avail vring.
+ */
+#define VDUSE_VQ_SETUP_KICKFD	_IOW(VDUSE_BASE, 0x16, struct vduse_vq_eventfd)
+
+/*
+ * Inject an interrupt for specific virtqueue. It's used to notify virtio driver
+ * to consume the used vring.
+ */
+#define VDUSE_VQ_INJECT_IRQ	_IOW(VDUSE_BASE, 0x17, __u32)
+
+/* The control messages definition for read(2)/write(2) on /dev/vduse/$NAME */
+
+/**
+ * enum vduse_req_type - request type
+ * @VDUSE_GET_VQ_STATE: get the state for specified virtqueue from userspace
+ * @VDUSE_SET_STATUS: set the device status
+ * @VDUSE_UPDATE_IOTLB: Notify userspace to update the memory mapping for
+ *                      specified IOVA range via VDUSE_IOTLB_GET_FD ioctl
+ */
+enum vduse_req_type {
+	VDUSE_GET_VQ_STATE,
+	VDUSE_SET_STATUS,
+	VDUSE_UPDATE_IOTLB,
+};
+
+/**
+ * struct vduse_vq_state - virtqueue state
+ * @index: virtqueue index
+ * @split: split virtqueue state
+ * @packed: packed virtqueue state
+ */
+struct vduse_vq_state {
+	__u32 index;
+	union {
+		struct vduse_vq_state_split split;
+		struct vduse_vq_state_packed packed;
+	};
+};
+
+/**
+ * struct vduse_dev_status - device status
+ * @status: device status
+ */
+struct vduse_dev_status {
+	__u8 status;
+};
+
+/**
+ * struct vduse_iova_range - IOVA range [start, last]
+ * @start: start of the IOVA range
+ * @last: last of the IOVA range
+ */
+struct vduse_iova_range {
+	__u64 start;
+	__u64 last;
+};
+
+/**
+ * struct vduse_dev_request - control request
+ * @type: request type
+ * @request_id: request id
+ * @reserved: for future use
+ * @vq_state: virtqueue state, only index field is available
+ * @s: device status
+ * @iova: IOVA range for updating
+ * @padding: padding
+ *
+ * Structure used by read(2) on /dev/vduse/$NAME.
+ */
+struct vduse_dev_request {
+	__u32 type;
+	__u32 request_id;
+	__u32 reserved[4];
+	union {
+		struct vduse_vq_state vq_state;
+		struct vduse_dev_status s;
+		struct vduse_iova_range iova;
+		__u32 padding[32];
+	};
+};
+
+/**
+ * struct vduse_dev_response - response to control request
+ * @request_id: corresponding request id
+ * @result: the result of request
+ * @reserved: for future use, needs to be initialized to zero
+ * @vq_state: virtqueue state
+ * @padding: padding
+ *
+ * Structure used by write(2) on /dev/vduse/$NAME.
+ */
+struct vduse_dev_response {
+	__u32 request_id;
+#define VDUSE_REQ_RESULT_OK	0x00
+#define VDUSE_REQ_RESULT_FAILED	0x01
+	__u32 result;
+	__u32 reserved[4];
+	union {
+		struct vduse_vq_state vq_state;
+		__u32 padding[32];
+	};
+};
+
+#endif /* _UAPI_VDUSE_H_ */
-- 
cgit v1.2.3


From 7bc7f61897b66bef78bb5952e3d1e9f3aaf9ccca Mon Sep 17 00:00:00 2001
From: Xie Yongji <xieyongji@bytedance.com>
Date: Tue, 31 Aug 2021 18:36:34 +0800
Subject: Documentation: Add documentation for VDUSE

VDUSE (vDPA Device in Userspace) is a framework to support
implementing software-emulated vDPA devices in userspace. This
document is intended to clarify the VDUSE design and usage.

Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20210831103634.33-14-xieyongji@bytedance.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
 Documentation/userspace-api/index.rst |   1 +
 Documentation/userspace-api/vduse.rst | 233 ++++++++++++++++++++++++++++++++++
 drivers/vdpa/vdpa_user/vduse_dev.c    |   5 -
 3 files changed, 234 insertions(+), 5 deletions(-)
 create mode 100644 Documentation/userspace-api/vduse.rst

(limited to 'drivers/vdpa')

diff --git a/Documentation/userspace-api/index.rst b/Documentation/userspace-api/index.rst
index 0b5eefed027e..c432be070f67 100644
--- a/Documentation/userspace-api/index.rst
+++ b/Documentation/userspace-api/index.rst
@@ -27,6 +27,7 @@ place where this information is gathered.
    iommu
    media/index
    sysfs-platform_profile
+   vduse
 
 .. only::  subproject and html
 
diff --git a/Documentation/userspace-api/vduse.rst b/Documentation/userspace-api/vduse.rst
new file mode 100644
index 000000000000..42ef59ea5314
--- /dev/null
+++ b/Documentation/userspace-api/vduse.rst
@@ -0,0 +1,233 @@
+==================================
+VDUSE - "vDPA Device in Userspace"
+==================================
+
+vDPA (virtio data path acceleration) device is a device that uses a
+datapath which complies with the virtio specifications with vendor
+specific control path. vDPA devices can be both physically located on
+the hardware or emulated by software. VDUSE is a framework that makes it
+possible to implement software-emulated vDPA devices in userspace. And
+to make the device emulation more secure, the emulated vDPA device's
+control path is handled in the kernel and only the data path is
+implemented in the userspace.
+
+Note that only virtio block device is supported by VDUSE framework now,
+which can reduce security risks when the userspace process that implements
+the data path is run by an unprivileged user. The support for other device
+types can be added after the security issue of corresponding device driver
+is clarified or fixed in the future.
+
+Create/Destroy VDUSE devices
+------------------------
+
+VDUSE devices are created as follows:
+
+1. Create a new VDUSE instance with ioctl(VDUSE_CREATE_DEV) on
+   /dev/vduse/control.
+
+2. Setup each virtqueue with ioctl(VDUSE_VQ_SETUP) on /dev/vduse/$NAME.
+
+3. Begin processing VDUSE messages from /dev/vduse/$NAME. The first
+   messages will arrive while attaching the VDUSE instance to vDPA bus.
+
+4. Send the VDPA_CMD_DEV_NEW netlink message to attach the VDUSE
+   instance to vDPA bus.
+
+VDUSE devices are destroyed as follows:
+
+1. Send the VDPA_CMD_DEV_DEL netlink message to detach the VDUSE
+   instance from vDPA bus.
+
+2. Close the file descriptor referring to /dev/vduse/$NAME.
+
+3. Destroy the VDUSE instance with ioctl(VDUSE_DESTROY_DEV) on
+   /dev/vduse/control.
+
+The netlink messages can be sent via vdpa tool in iproute2 or use the
+below sample codes:
+
+.. code-block:: c
+
+	static int netlink_add_vduse(const char *name, enum vdpa_command cmd)
+	{
+		struct nl_sock *nlsock;
+		struct nl_msg *msg;
+		int famid;
+
+		nlsock = nl_socket_alloc();
+		if (!nlsock)
+			return -ENOMEM;
+
+		if (genl_connect(nlsock))
+			goto free_sock;
+
+		famid = genl_ctrl_resolve(nlsock, VDPA_GENL_NAME);
+		if (famid < 0)
+			goto close_sock;
+
+		msg = nlmsg_alloc();
+		if (!msg)
+			goto close_sock;
+
+		if (!genlmsg_put(msg, NL_AUTO_PORT, NL_AUTO_SEQ, famid, 0, 0, cmd, 0))
+			goto nla_put_failure;
+
+		NLA_PUT_STRING(msg, VDPA_ATTR_DEV_NAME, name);
+		if (cmd == VDPA_CMD_DEV_NEW)
+			NLA_PUT_STRING(msg, VDPA_ATTR_MGMTDEV_DEV_NAME, "vduse");
+
+		if (nl_send_sync(nlsock, msg))
+			goto close_sock;
+
+		nl_close(nlsock);
+		nl_socket_free(nlsock);
+
+		return 0;
+	nla_put_failure:
+		nlmsg_free(msg);
+	close_sock:
+		nl_close(nlsock);
+	free_sock:
+		nl_socket_free(nlsock);
+		return -1;
+	}
+
+How VDUSE works
+---------------
+
+As mentioned above, a VDUSE device is created by ioctl(VDUSE_CREATE_DEV) on
+/dev/vduse/control. With this ioctl, userspace can specify some basic configuration
+such as device name (uniquely identify a VDUSE device), virtio features, virtio
+configuration space, the number of virtqueues and so on for this emulated device.
+Then a char device interface (/dev/vduse/$NAME) is exported to userspace for device
+emulation. Userspace can use the VDUSE_VQ_SETUP ioctl on /dev/vduse/$NAME to
+add per-virtqueue configuration such as the max size of virtqueue to the device.
+
+After the initialization, the VDUSE device can be attached to vDPA bus via
+the VDPA_CMD_DEV_NEW netlink message. Userspace needs to read()/write() on
+/dev/vduse/$NAME to receive/reply some control messages from/to VDUSE kernel
+module as follows:
+
+.. code-block:: c
+
+	static int vduse_message_handler(int dev_fd)
+	{
+		int len;
+		struct vduse_dev_request req;
+		struct vduse_dev_response resp;
+
+		len = read(dev_fd, &req, sizeof(req));
+		if (len != sizeof(req))
+			return -1;
+
+		resp.request_id = req.request_id;
+
+		switch (req.type) {
+
+		/* handle different types of messages */
+
+		}
+
+		len = write(dev_fd, &resp, sizeof(resp));
+		if (len != sizeof(resp))
+			return -1;
+
+		return 0;
+	}
+
+There are now three types of messages introduced by VDUSE framework:
+
+- VDUSE_GET_VQ_STATE: Get the state for virtqueue, userspace should return
+  avail index for split virtqueue or the device/driver ring wrap counters and
+  the avail and used index for packed virtqueue.
+
+- VDUSE_SET_STATUS: Set the device status, userspace should follow
+  the virtio spec: https://docs.oasis-open.org/virtio/virtio/v1.1/virtio-v1.1.html
+  to process this message. For example, fail to set the FEATURES_OK device
+  status bit if the device can not accept the negotiated virtio features
+  get from the VDUSE_DEV_GET_FEATURES ioctl.
+
+- VDUSE_UPDATE_IOTLB: Notify userspace to update the memory mapping for specified
+  IOVA range, userspace should firstly remove the old mapping, then setup the new
+  mapping via the VDUSE_IOTLB_GET_FD ioctl.
+
+After DRIVER_OK status bit is set via the VDUSE_SET_STATUS message, userspace is
+able to start the dataplane processing as follows:
+
+1. Get the specified virtqueue's information with the VDUSE_VQ_GET_INFO ioctl,
+   including the size, the IOVAs of descriptor table, available ring and used ring,
+   the state and the ready status.
+
+2. Pass the above IOVAs to the VDUSE_IOTLB_GET_FD ioctl so that those IOVA regions
+   can be mapped into userspace. Some sample codes is shown below:
+
+.. code-block:: c
+
+	static int perm_to_prot(uint8_t perm)
+	{
+		int prot = 0;
+
+		switch (perm) {
+		case VDUSE_ACCESS_WO:
+			prot |= PROT_WRITE;
+			break;
+		case VDUSE_ACCESS_RO:
+			prot |= PROT_READ;
+			break;
+		case VDUSE_ACCESS_RW:
+			prot |= PROT_READ | PROT_WRITE;
+			break;
+		}
+
+		return prot;
+	}
+
+	static void *iova_to_va(int dev_fd, uint64_t iova, uint64_t *len)
+	{
+		int fd;
+		void *addr;
+		size_t size;
+		struct vduse_iotlb_entry entry;
+
+		entry.start = iova;
+		entry.last = iova;
+
+		/*
+		 * Find the first IOVA region that overlaps with the specified
+		 * range [start, last] and return the corresponding file descriptor.
+		 */
+		fd = ioctl(dev_fd, VDUSE_IOTLB_GET_FD, &entry);
+		if (fd < 0)
+			return NULL;
+
+		size = entry.last - entry.start + 1;
+		*len = entry.last - iova + 1;
+		addr = mmap(0, size, perm_to_prot(entry.perm), MAP_SHARED,
+			    fd, entry.offset);
+		close(fd);
+		if (addr == MAP_FAILED)
+			return NULL;
+
+		/*
+		 * Using some data structures such as linked list to store
+		 * the iotlb mapping. The munmap(2) should be called for the
+		 * cached mapping when the corresponding VDUSE_UPDATE_IOTLB
+		 * message is received or the device is reset.
+		 */
+
+		return addr + iova - entry.start;
+	}
+
+3. Setup the kick eventfd for the specified virtqueues with the VDUSE_VQ_SETUP_KICKFD
+   ioctl. The kick eventfd is used by VDUSE kernel module to notify userspace to
+   consume the available ring. This is optional since userspace can choose to poll the
+   available ring instead.
+
+4. Listen to the kick eventfd (optional) and consume the available ring. The buffer
+   described by the descriptors in the descriptor table should be also mapped into
+   userspace via the VDUSE_IOTLB_GET_FD ioctl before accessing.
+
+5. Inject an interrupt for specific virtqueue with the VDUSE_INJECT_VQ_IRQ ioctl
+   after the used ring is filled.
+
+For more details on the uAPI, please see include/uapi/linux/vduse.h.
diff --git a/drivers/vdpa/vdpa_user/vduse_dev.c b/drivers/vdpa/vdpa_user/vduse_dev.c
index b9b2659408e6..59a93e5b967a 100644
--- a/drivers/vdpa/vdpa_user/vduse_dev.c
+++ b/drivers/vdpa/vdpa_user/vduse_dev.c
@@ -486,11 +486,6 @@ static void vduse_vdpa_kick_vq(struct vdpa_device *vdpa, u16 idx)
 	struct vduse_dev *dev = vdpa_to_vduse(vdpa);
 	struct vduse_virtqueue *vq = &dev->vqs[idx];
 
-	/*
-	 * TODO: after applying b542e383d8c0 ("eventfd: Make signal recursion protection a task bit")
-	 * replace eventfd_signal_count with eventfd_signal_allowed, and
-	 * drop the previous ("eventfd: Export eventfd_wake_count to modules") 
-	 * */
 	if (eventfd_signal_count()) {
 		schedule_work(&vq->kick);
 		return;
-- 
cgit v1.2.3