Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

Pull virtio updates from Michael Tsirkin:
 "vhost,virtio,vdpa: features, fixes, cleanups.

  vdpa/mlx5:
   - VHOST_BACKEND_F_ENABLE_AFTER_DRIVER_OK
   - new maintainer

  vdpa:
   - support for vq descriptor mappings
   - decouple reset of iotlb mapping from device reset

  and fixes, cleanups all over the place"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (34 commits)
  vdpa_sim: implement .reset_map support
  vdpa/mlx5: implement .reset_map driver op
  vhost-vdpa: clean iotlb map during reset for older userspace
  vdpa: introduce .compat_reset operation callback
  vhost-vdpa: introduce IOTLB_PERSIST backend feature bit
  vhost-vdpa: reset vendor specific mapping to initial state in .release
  vdpa: introduce .reset_map operation callback
  virtio_pci: add check for common cfg size
  virtio-blk: fix implicit overflow on virtio_max_dma_size
  virtio_pci: add build offset check for the new common cfg items
  virtio: add definition of VIRTIO_F_NOTIF_CONFIG_DATA feature bit
  vduse: make vduse_class constant
  vhost-scsi: Spelling s/preceeding/preceding/g
  virtio: kdoc for struct virtio_pci_modern_device
  vdpa: Update sysfs ABI documentation
  MAINTAINERS: Add myself as mlx5_vdpa driver
  virtio-balloon: correct the comment of virtballoon_migratepage()
  mlx5_vdpa: offer VHOST_BACKEND_F_ENABLE_AFTER_DRIVER_OK
  vdpa/mlx5: Update cvq iotlb mapping on ASID change
  vdpa/mlx5: Make iotlb helper functions more generic
  ...

1 files changed, 39 insertions, 2 deletions

diff --git a/include/linux/vdpa.h b/include/linux/vdpa.h
index 0e652026b776..db15ac07f8a6 100644
--- a/include/linux/vdpa.h
+++ b/include/linux/vdpa.h
@@ -204,6 +204,16 @@ struct vdpa_map_file {
  *				@vdev: vdpa device
  *				@idx: virtqueue index
  *				Returns u32: group id for this virtqueue
+ * @get_vq_desc_group:		Get the group id for the descriptor table of
+ *				a specific virtqueue (optional)
+ *				@vdev: vdpa device
+ *				@idx: virtqueue index
+ *				Returns u32: group id for the descriptor table
+ *				portion of this virtqueue. Could be different
+ *				than the one from @get_vq_group, in which case
+ *				the access to the descriptor table can be
+ *				confined to a separate asid, isolating from
+ *				the virtqueue's buffer address access.
  * @get_device_features:	Get virtio features supported by the device
  *				@vdev: vdpa device
  *				Returns the virtio features support by the
@@ -242,6 +252,17 @@ struct vdpa_map_file {
  * @reset:			Reset device
  *				@vdev: vdpa device
  *				Returns integer: success (0) or error (< 0)
+ * @compat_reset:		Reset device with compatibility quirks to
+ *				accommodate older userspace. Only needed by
+ *				parent driver which used to have bogus reset
+ *				behaviour, and has to maintain such behaviour
+ *				for compatibility with older userspace.
+ *				Historically compliant driver only has to
+ *				implement .reset, Historically non-compliant
+ *				driver should implement both.
+ *				@vdev: vdpa device
+ *				@flags: compatibility quirks for reset
+ *				Returns integer: success (0) or error (< 0)
  * @suspend:			Suspend the device (optional)
  *				@vdev: vdpa device
  *				Returns integer: success (0) or error (< 0)
@@ -317,6 +338,15 @@ struct vdpa_map_file {
  *				@iova: iova to be unmapped
  *				@size: size of the area
  *				Returns integer: success (0) or error (< 0)
+ * @reset_map:			Reset device memory mapping to the default
+ *				state (optional)
+ *				Needed for devices that are using device
+ *				specific DMA translation and prefer mapping
+ *				to be decoupled from the virtio life cycle,
+ *				i.e. device .reset op does not reset mapping
+ *				@vdev: vdpa device
+ *				@asid: address space identifier
+ *				Returns integer: success (0) or error (< 0)
  * @get_vq_dma_dev:		Get the dma device for a specific
  *				virtqueue (optional)
  *				@vdev: vdpa device
@@ -360,6 +390,7 @@ struct vdpa_config_ops {
 	/* Device ops */
 	u32 (*get_vq_align)(struct vdpa_device *vdev);
 	u32 (*get_vq_group)(struct vdpa_device *vdev, u16 idx);
+	u32 (*get_vq_desc_group)(struct vdpa_device *vdev, u16 idx);
 	u64 (*get_device_features)(struct vdpa_device *vdev);
 	u64 (*get_backend_features)(const struct vdpa_device *vdev);
 	int (*set_driver_features)(struct vdpa_device *vdev, u64 features);
@@ -373,6 +404,8 @@ 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 (*compat_reset)(struct vdpa_device *vdev, u32 flags);
+#define VDPA_RESET_F_CLEAN_MAP 1
 	int (*suspend)(struct vdpa_device *vdev);
 	int (*resume)(struct vdpa_device *vdev);
 	size_t (*get_config_size)(struct vdpa_device *vdev);
@@ -394,6 +427,7 @@ struct vdpa_config_ops {
 		       u64 iova, u64 size, u64 pa, u32 perm, void *opaque);
 	int (*dma_unmap)(struct vdpa_device *vdev, unsigned int asid,
 			 u64 iova, u64 size);
+	int (*reset_map)(struct vdpa_device *vdev, unsigned int asid);
 	int (*set_group_asid)(struct vdpa_device *vdev, unsigned int group,
 			      unsigned int asid);
 	struct device *(*get_vq_dma_dev)(struct vdpa_device *vdev, u16 idx);
@@ -485,14 +519,17 @@ static inline struct device *vdpa_get_dma_dev(struct vdpa_device *vdev)
 	return vdev->dma_dev;
 }
 
-static inline int vdpa_reset(struct vdpa_device *vdev)
+static inline int vdpa_reset(struct vdpa_device *vdev, u32 flags)
 {
 	const struct vdpa_config_ops *ops = vdev->config;
 	int ret;
 
 	down_write(&vdev->cf_lock);
 	vdev->features_valid = false;
-	ret = ops->reset(vdev);
+	if (ops->compat_reset && flags)
+		ret = ops->compat_reset(vdev, flags);
+	else
+		ret = ops->reset(vdev);
 	up_write(&vdev->cf_lock);
 	return ret;
 }