Merge branch 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost.git

drivers/remoteproc/remoteproc_core.c

@@ -334,7 +334,7 @@ int rproc_alloc_vring(struct rproc_vdev *rvdev, int i)
 	size_t size;
 
 	/* actual size of vring (in bytes) */
-	size = PAGE_ALIGN(vring_size(rvring->len, rvring->align));
+	size = PAGE_ALIGN(vring_size(rvring->num, rvring->align));
 
 	rsc = (void *)rproc->table_ptr + rvdev->rsc_offset;
 
@@ -401,7 +401,7 @@ rproc_parse_vring(struct rproc_vdev *rvdev, struct fw_rsc_vdev *rsc, int i)
 		return -EINVAL;
 	}
 
-	rvring->len = vring->num;
+	rvring->num = vring->num;
 	rvring->align = vring->align;
 	rvring->rvdev = rvdev;
 

drivers/remoteproc/remoteproc_virtio.c

@@ -87,7 +87,7 @@ static struct virtqueue *rp_find_vq(struct virtio_device *vdev,
 	struct fw_rsc_vdev *rsc;
 	struct virtqueue *vq;
 	void *addr;
-	int len, size;
+	int num, size;
 
 	/* we're temporarily limited to two virtqueues per rvdev */
 	if (id >= ARRAY_SIZE(rvdev->vring))
@@ -104,20 +104,20 @@ static struct virtqueue *rp_find_vq(struct virtio_device *vdev,
 
 	rvring = &rvdev->vring[id];
 	addr = mem->va;
-	len = rvring->len;
+	num = rvring->num;
 
 	/* zero vring */
-	size = vring_size(len, rvring->align);
+	size = vring_size(num, rvring->align);
 	memset(addr, 0, size);
 
 	dev_dbg(dev, "vring%d: va %pK qsz %d notifyid %d\n",
-		id, addr, len, rvring->notifyid);
+		id, addr, num, rvring->notifyid);
 
 	/*
 	 * Create the new vq, and tell virtio we're not interested in
 	 * the 'weak' smp barriers, since we're talking with a real device.
 	 */
-	vq = vring_new_virtqueue(id, len, rvring->align, vdev, false, ctx,
+	vq = vring_new_virtqueue(id, num, rvring->align, vdev, false, ctx,
 				 addr, rproc_virtio_notify, callback, name);
 	if (!vq) {
 		dev_err(dev, "vring_new_virtqueue %s failed\n", name);

drivers/vdpa/vdpa_sim/vdpa_sim.c

@@ -107,6 +107,7 @@ static void vdpasim_do_reset(struct vdpasim *vdpasim)
 	for (i = 0; i < vdpasim->dev_attr.nas; i++)
 		vhost_iotlb_reset(&vdpasim->iommu[i]);
 
+	vdpasim->running = true;
 	spin_unlock(&vdpasim->iommu_lock);
 
 	vdpasim->features = 0;
@@ -505,6 +506,24 @@ static int vdpasim_reset(struct vdpa_device *vdpa)
 	return 0;
 }
 
+static int vdpasim_suspend(struct vdpa_device *vdpa)
+{
+	struct vdpasim *vdpasim = vdpa_to_sim(vdpa);
+	int i;
+
+	spin_lock(&vdpasim->lock);
+	vdpasim->running = false;
+	if (vdpasim->running) {
+		/* Check for missed buffers */
+		for (i = 0; i < vdpasim->dev_attr.nvqs; ++i)
+			vdpasim_kick_vq(vdpa, i);
+
+	}
+	spin_unlock(&vdpasim->lock);
+
+	return 0;
+}
+
 static size_t vdpasim_get_config_size(struct vdpa_device *vdpa)
 {
 	struct vdpasim *vdpasim = vdpa_to_sim(vdpa);
@@ -694,6 +713,7 @@ static const struct vdpa_config_ops vdpasim_config_ops = {
 	.get_status             = vdpasim_get_status,
 	.set_status             = vdpasim_set_status,
 	.reset			= vdpasim_reset,
+	.suspend		= vdpasim_suspend,
 	.get_config_size        = vdpasim_get_config_size,
 	.get_config             = vdpasim_get_config,
 	.set_config             = vdpasim_set_config,
@@ -726,6 +746,7 @@ static const struct vdpa_config_ops vdpasim_batch_config_ops = {
 	.get_status             = vdpasim_get_status,
 	.set_status             = vdpasim_set_status,
 	.reset			= vdpasim_reset,
+	.suspend		= vdpasim_suspend,
 	.get_config_size        = vdpasim_get_config_size,
 	.get_config             = vdpasim_get_config,
 	.set_config             = vdpasim_set_config,

drivers/vdpa/vdpa_sim/vdpa_sim.h

@@ -66,6 +66,7 @@ struct vdpasim {
 	u32 generation;
 	u64 features;
 	u32 groups;
+	bool running;
 	/* spinlock to synchronize iommu table */
 	spinlock_t iommu_lock;
 };

drivers/vdpa/vdpa_sim/vdpa_sim_blk.c

@@ -204,6 +204,9 @@ static void vdpasim_blk_work(struct work_struct *work)
 	if (!(vdpasim->status & VIRTIO_CONFIG_S_DRIVER_OK))
 		goto out;
 
+	if (!vdpasim->running)
+		goto out;
+
 	for (i = 0; i < VDPASIM_BLK_VQ_NUM; i++) {
 		struct vdpasim_virtqueue *vq = &vdpasim->vqs[i];
 

drivers/vdpa/vdpa_sim/vdpa_sim_net.c

@@ -154,6 +154,9 @@ static void vdpasim_net_work(struct work_struct *work)
 
 	spin_lock(&vdpasim->lock);
 
+	if (!vdpasim->running)
+		goto out;
+
 	if (!(vdpasim->status & VIRTIO_CONFIG_S_DRIVER_OK))
 		goto out;
 

drivers/vhost/vdpa.c

@@ -347,6 +347,14 @@ static long vhost_vdpa_set_config(struct vhost_vdpa *v,
 	return 0;
 }
 
+static bool vhost_vdpa_can_suspend(const struct vhost_vdpa *v)
+{
+	struct vdpa_device *vdpa = v->vdpa;
+	const struct vdpa_config_ops *ops = vdpa->config;
+
+	return ops->suspend;
+}
+
 static long vhost_vdpa_get_features(struct vhost_vdpa *v, u64 __user *featurep)
 {
 	struct vdpa_device *vdpa = v->vdpa;
@@ -470,6 +478,22 @@ static long vhost_vdpa_get_vqs_count(struct vhost_vdpa *v, u32 __user *argp)
 	return 0;
 }
 
+/* After a successful return of ioctl the device must not process more
+ * virtqueue descriptors. The device can answer to read or writes of config
+ * fields as if it were not suspended. In particular, writing to "queue_enable"
+ * with a value of 1 will not make the device start processing buffers.
+ */
+static long vhost_vdpa_suspend(struct vhost_vdpa *v)
+{
+	struct vdpa_device *vdpa = v->vdpa;
+	const struct vdpa_config_ops *ops = vdpa->config;
+
+	if (!ops->suspend)
+		return -EOPNOTSUPP;
+
+	return ops->suspend(vdpa);
+}
+
 static long vhost_vdpa_vring_ioctl(struct vhost_vdpa *v, unsigned int cmd,
 				   void __user *argp)
 {
@@ -577,7 +601,11 @@ static long vhost_vdpa_unlocked_ioctl(struct file *filep,
 	if (cmd == VHOST_SET_BACKEND_FEATURES) {
 		if (copy_from_user(&features, featurep, sizeof(features)))
 			return -EFAULT;
-		if (features & ~VHOST_VDPA_BACKEND_FEATURES)
+		if (features & ~(VHOST_VDPA_BACKEND_FEATURES |
+				 BIT_ULL(VHOST_BACKEND_F_SUSPEND)))
+			return -EOPNOTSUPP;
+		if ((features & BIT_ULL(VHOST_BACKEND_F_SUSPEND)) &&
+		     !vhost_vdpa_can_suspend(v))
 			return -EOPNOTSUPP;
 		vhost_set_backend_features(&v->vdev, features);
 		return 0;
@@ -628,6 +656,8 @@ static long vhost_vdpa_unlocked_ioctl(struct file *filep,
 		break;
 	case VHOST_GET_BACKEND_FEATURES:
 		features = VHOST_VDPA_BACKEND_FEATURES;
+		if (vhost_vdpa_can_suspend(v))
+			features |= BIT_ULL(VHOST_BACKEND_F_SUSPEND);
 		if (copy_to_user(featurep, &features, sizeof(features)))
 			r = -EFAULT;
 		break;
@@ -640,6 +670,9 @@ static long vhost_vdpa_unlocked_ioctl(struct file *filep,
 	case VHOST_VDPA_GET_VQS_COUNT:
 		r = vhost_vdpa_get_vqs_count(v, argp);
 		break;
+	case VHOST_VDPA_SUSPEND:
+		r = vhost_vdpa_suspend(v);
+		break;
 	default:
 		r = vhost_dev_ioctl(&v->vdev, cmd, argp);
 		if (r == -ENOIOCTLCMD)

drivers/vhost/vringh.c

@@ -1095,7 +1095,8 @@ EXPORT_SYMBOL(vringh_need_notify_kern);
 #if IS_REACHABLE(CONFIG_VHOST_IOTLB)
 
 static int iotlb_translate(const struct vringh *vrh,
-			   u64 addr, u64 len, struct bio_vec iov[],
+			   u64 addr, u64 len, u64 *translated,
+			   struct bio_vec iov[],
 			   int iov_size, u32 perm)
 {
 	struct vhost_iotlb_map *map;
@@ -1136,43 +1137,76 @@ static int iotlb_translate(const struct vringh *vrh,
 
 	spin_unlock(vrh->iotlb_lock);
 
+	if (translated)
+		*translated = min(len, s);
+
 	return ret;
 }
 
 static inline int copy_from_iotlb(const struct vringh *vrh, void *dst,
 				  void *src, size_t len)
 {
-	struct iov_iter iter;
-	struct bio_vec iov[16];
-	int ret;
+	u64 total_translated = 0;
 
-	ret = iotlb_translate(vrh, (u64)(uintptr_t)src,
-			      len, iov, 16, VHOST_MAP_RO);
-	if (ret < 0)
-		return ret;
+	while (total_translated < len) {
+		struct bio_vec iov[16];
+		struct iov_iter iter;
+		u64 translated;
+		int ret;
 
-	iov_iter_bvec(&iter, READ, iov, ret, len);
+		ret = iotlb_translate(vrh, (u64)(uintptr_t)src,
+				      len - total_translated, &translated,
+				      iov, ARRAY_SIZE(iov), VHOST_MAP_RO);
+		if (ret == -ENOBUFS)
+			ret = ARRAY_SIZE(iov);
+		else if (ret < 0)
+			return ret;
 
-	ret = copy_from_iter(dst, len, &iter);
+		iov_iter_bvec(&iter, READ, iov, ret, translated);
 
-	return ret;
+		ret = copy_from_iter(dst, translated, &iter);
+		if (ret < 0)
+			return ret;
+
+		src += translated;
+		dst += translated;
+		total_translated += translated;
+	}
+
+	return total_translated;
 }
 
 static inline int copy_to_iotlb(const struct vringh *vrh, void *dst,
 				void *src, size_t len)
 {
-	struct iov_iter iter;
-	struct bio_vec iov[16];
-	int ret;
+	u64 total_translated = 0;
 
-	ret = iotlb_translate(vrh, (u64)(uintptr_t)dst,
-			      len, iov, 16, VHOST_MAP_WO);
-	if (ret < 0)
-		return ret;
+	while (total_translated < len) {
+		struct bio_vec iov[16];
+		struct iov_iter iter;
+		u64 translated;
+		int ret;
 
-	iov_iter_bvec(&iter, WRITE, iov, ret, len);
+		ret = iotlb_translate(vrh, (u64)(uintptr_t)dst,
+				      len - total_translated, &translated,
+				      iov, ARRAY_SIZE(iov), VHOST_MAP_WO);
+		if (ret == -ENOBUFS)
+			ret = ARRAY_SIZE(iov);
+		else if (ret < 0)
+			return ret;
 
-	return copy_to_iter(src, len, &iter);
+		iov_iter_bvec(&iter, WRITE, iov, ret, translated);
+
+		ret = copy_to_iter(src, translated, &iter);
+		if (ret < 0)
+			return ret;
+
+		src += translated;
+		dst += translated;
+		total_translated += translated;
+	}
+
+	return total_translated;
 }
 
 static inline int getu16_iotlb(const struct vringh *vrh,
@@ -1183,7 +1217,7 @@ static inline int getu16_iotlb(const struct vringh *vrh,
 	int ret;
 
 	/* Atomic read is needed for getu16 */
-	ret = iotlb_translate(vrh, (u64)(uintptr_t)p, sizeof(*p),
+	ret = iotlb_translate(vrh, (u64)(uintptr_t)p, sizeof(*p), NULL,
 			      &iov, 1, VHOST_MAP_RO);
 	if (ret < 0)
 		return ret;
@@ -1204,7 +1238,7 @@ static inline int putu16_iotlb(const struct vringh *vrh,
 	int ret;
 
 	/* Atomic write is needed for putu16 */
-	ret = iotlb_translate(vrh, (u64)(uintptr_t)p, sizeof(*p),
+	ret = iotlb_translate(vrh, (u64)(uintptr_t)p, sizeof(*p), NULL,
 			      &iov, 1, VHOST_MAP_WO);
 	if (ret < 0)
 		return ret;

drivers/virtio/virtio_ring.c

@@ -1637,8 +1637,7 @@ static void *virtqueue_detach_unused_buf_packed(struct virtqueue *_vq)
 	return NULL;
 }
 
-static struct vring_desc_extra *vring_alloc_desc_extra(struct vring_virtqueue *vq,
-						       unsigned int num)
+static struct vring_desc_extra *vring_alloc_desc_extra(unsigned int num)
 {
 	struct vring_desc_extra *desc_extra;
 	unsigned int i;
@@ -1759,7 +1758,7 @@ static struct virtqueue *vring_create_virtqueue_packed(
 	/* Put everything in free lists. */
 	vq->free_head = 0;
 
-	vq->packed.desc_extra = vring_alloc_desc_extra(vq, num);
+	vq->packed.desc_extra = vring_alloc_desc_extra(num);
 	if (!vq->packed.desc_extra)
 		goto err_desc_extra;
 
@@ -2248,7 +2247,7 @@ struct virtqueue *__vring_new_virtqueue(unsigned int index,
 	if (!vq->split.desc_state)
 		goto err_state;
 
-	vq->split.desc_extra = vring_alloc_desc_extra(vq, vring.num);
+	vq->split.desc_extra = vring_alloc_desc_extra(vring.num);
 	if (!vq->split.desc_extra)
 		goto err_extra;
 

include/linux/remoteproc.h

@@ -597,7 +597,7 @@ struct rproc_subdev {
 /**
  * struct rproc_vring - remoteproc vring state
  * @va:	virtual address
- * @len: length, in bytes
+ * @num: vring size
  * @da: device address
  * @align: vring alignment
  * @notifyid: rproc-specific unique vring index
@@ -606,7 +606,7 @@ struct rproc_subdev {
  */
 struct rproc_vring {
 	void *va;
-	int len;
+	int num;
 	u32 da;
 	u32 align;
 	int notifyid;

include/linux/vdpa.h

@@ -218,6 +218,9 @@ struct vdpa_map_file {
  * @reset:			Reset device
  *				@vdev: vdpa device
  *				Returns integer: success (0) or error (< 0)
+ * @suspend:			Suspend or resume the device (optional)
+ *				@vdev: vdpa device
+ *				Returns integer: success (0) or error (< 0)
  * @get_config_size:		Get the size of the configuration space includes
  *				fields that are conditional on feature bits.
  *				@vdev: vdpa device
@@ -319,6 +322,7 @@ struct vdpa_config_ops {
 	u8 (*get_status)(struct vdpa_device *vdev);
 	void (*set_status)(struct vdpa_device *vdev, u8 status);
 	int (*reset)(struct vdpa_device *vdev);
+	int (*suspend)(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);

include/uapi/linux/vhost.h

@@ -171,4 +171,18 @@
 #define VHOST_VDPA_SET_GROUP_ASID	_IOW(VHOST_VIRTIO, 0x7C, \
 					     struct vhost_vring_state)
 
+/* Suspend or resume a device so it does not process virtqueue requests anymore
+ *
+ * After the return of ioctl with suspend != 0, the device must finish any
+ * pending operations like in flight requests. It must also preserve all the
+ * necessary state (the virtqueue vring base plus the possible device specific
+ * states) that is required for restoring in the future. The device must not
+ * change its configuration after that point.
+ *
+ * After the return of ioctl with suspend == 0, the device can continue
+ * processing buffers as long as typical conditions are met (vq is enabled,
+ * DRIVER_OK status bit is enabled, etc).
+ */
+#define VHOST_VDPA_SUSPEND		_IOW(VHOST_VIRTIO, 0x7D, int)
+
 #endif

include/uapi/linux/vhost_types.h

@@ -161,5 +161,7 @@ struct vhost_vdpa_iova_range {
  * message
  */
 #define VHOST_BACKEND_F_IOTLB_ASID  0x3
+/* Device can be suspended */
+#define VHOST_BACKEND_F_SUSPEND  0x4
 
 #endif