vfio: VFIO_DEVICE_[AT|DE]TACH_IOMMUFD_PT support pasid

This extends the VFIO_DEVICE_[AT|DE]TACH_IOMMUFD_PT ioctls to attach/detach
a given pasid of a vfio device to/from an IOAS/HWPT.

Link: https://patch.msgid.link/r/20250321180143.8468-4-yi.l.liu@intel.com
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Nicolin Chen <nicolinc@nvidia.com>
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

diff --git a/drivers/vfio/device_cdev.c b/drivers/vfio/device_cdev.c
index bb1817bd4ff319d72bed19e846ddcc598fc6d280..281a8dc3ed49741d2e7fa6fbf03a9bc80374b9a5 100644 (file)
--- a/drivers/vfio/device_cdev.c
+++ b/drivers/vfio/device_cdev.c
@@ -162,9 +162,9 @@ void vfio_df_unbind_iommufd(struct vfio_device_file *df)
 int vfio_df_ioctl_attach_pt(struct vfio_device_file *df,
                            struct vfio_device_attach_iommufd_pt __user *arg)
 {
-       struct vfio_device *device = df->device;
        struct vfio_device_attach_iommufd_pt attach;
-       unsigned long minsz;
+       struct vfio_device *device = df->device;
+       unsigned long minsz, xend = 0;
        int ret;
 
        minsz = offsetofend(struct vfio_device_attach_iommufd_pt, pt_id);
@@ -172,11 +172,34 @@ int vfio_df_ioctl_attach_pt(struct vfio_device_file *df,
        if (copy_from_user(&attach, arg, minsz))
                return -EFAULT;
 
-       if (attach.argsz < minsz || attach.flags)
+       if (attach.argsz < minsz)
                return -EINVAL;
 
+       if (attach.flags & ~VFIO_DEVICE_ATTACH_PASID)
+               return -EINVAL;
+
+       if (attach.flags & VFIO_DEVICE_ATTACH_PASID) {
+               if (!device->ops->pasid_attach_ioas)
+                       return -EOPNOTSUPP;
+               xend = offsetofend(struct vfio_device_attach_iommufd_pt, pasid);
+       }
+
+       if (xend) {
+               if (attach.argsz < xend)
+                       return -EINVAL;
+
+               if (copy_from_user((void *)&attach + minsz,
+                                  (void __user *)arg + minsz, xend - minsz))
+                       return -EFAULT;
+       }
+
        mutex_lock(&device->dev_set->lock);
-       ret = device->ops->attach_ioas(device, &attach.pt_id);
+       if (attach.flags & VFIO_DEVICE_ATTACH_PASID)
+               ret = device->ops->pasid_attach_ioas(device,
+                                                    attach.pasid,
+                                                    &attach.pt_id);
+       else
+               ret = device->ops->attach_ioas(device, &attach.pt_id);
        if (ret)
                goto out_unlock;
 
@@ -198,20 +221,41 @@ out_unlock:
 int vfio_df_ioctl_detach_pt(struct vfio_device_file *df,
                            struct vfio_device_detach_iommufd_pt __user *arg)
 {
-       struct vfio_device *device = df->device;
        struct vfio_device_detach_iommufd_pt detach;
-       unsigned long minsz;
+       struct vfio_device *device = df->device;
+       unsigned long minsz, xend = 0;
 
        minsz = offsetofend(struct vfio_device_detach_iommufd_pt, flags);
 
        if (copy_from_user(&detach, arg, minsz))
                return -EFAULT;
 
-       if (detach.argsz < minsz || detach.flags)
+       if (detach.argsz < minsz)
                return -EINVAL;
 
+       if (detach.flags & ~VFIO_DEVICE_DETACH_PASID)
+               return -EINVAL;
+
+       if (detach.flags & VFIO_DEVICE_DETACH_PASID) {
+               if (!device->ops->pasid_detach_ioas)
+                       return -EOPNOTSUPP;
+               xend = offsetofend(struct vfio_device_detach_iommufd_pt, pasid);
+       }
+
+       if (xend) {
+               if (detach.argsz < xend)
+                       return -EINVAL;
+
+               if (copy_from_user((void *)&detach + minsz,
+                                  (void __user *)arg + minsz, xend - minsz))
+                       return -EFAULT;
+       }
+
        mutex_lock(&device->dev_set->lock);
-       device->ops->detach_ioas(device);
+       if (detach.flags & VFIO_DEVICE_DETACH_PASID)
+               device->ops->pasid_detach_ioas(device, detach.pasid);
+       else
+               device->ops->detach_ioas(device);
        mutex_unlock(&device->dev_set->lock);
 
        return 0;

diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h
index c8dbf8219c4fcb296fe48d40fa892f172838b579..6899da70b929f3da860aaf45698eeeecc37fd679 100644 (file)
--- a/include/uapi/linux/vfio.h
+++ b/include/uapi/linux/vfio.h
@@ -931,29 +931,34 @@ struct vfio_device_bind_iommufd {
  * VFIO_DEVICE_ATTACH_IOMMUFD_PT - _IOW(VFIO_TYPE, VFIO_BASE + 19,
  *                                     struct vfio_device_attach_iommufd_pt)
  * @argsz:     User filled size of this data.
- * @flags:     Must be 0.
+ * @flags:     Flags for attach.
  * @pt_id:     Input the target id which can represent an ioas or a hwpt
  *             allocated via iommufd subsystem.
  *             Output the input ioas id or the attached hwpt id which could
  *             be the specified hwpt itself or a hwpt automatically created
  *             for the specified ioas by kernel during the attachment.
+ * @pasid:     The pasid to be attached, only meaningful when
+ *             VFIO_DEVICE_ATTACH_PASID is set in @flags
  *
  * Associate the device with an address space within the bound iommufd.
  * Undo by VFIO_DEVICE_DETACH_IOMMUFD_PT or device fd close.  This is only
  * allowed on cdev fds.
  *
- * If a vfio device is currently attached to a valid hw_pagetable, without doing
- * a VFIO_DEVICE_DETACH_IOMMUFD_PT, a second VFIO_DEVICE_ATTACH_IOMMUFD_PT ioctl
- * passing in another hw_pagetable (hwpt) id is allowed. This action, also known
- * as a hw_pagetable replacement, will replace the device's currently attached
- * hw_pagetable with a new hw_pagetable corresponding to the given pt_id.
+ * If a vfio device or a pasid of this device is currently attached to a valid
+ * hw_pagetable (hwpt), without doing a VFIO_DEVICE_DETACH_IOMMUFD_PT, a second
+ * VFIO_DEVICE_ATTACH_IOMMUFD_PT ioctl passing in another hwpt id is allowed.
+ * This action, also known as a hw_pagetable replacement, will replace the
+ * currently attached hwpt of the device or the pasid of this device with a new
+ * hwpt corresponding to the given pt_id.
  *
  * Return: 0 on success, -errno on failure.
  */
 struct vfio_device_attach_iommufd_pt {
        __u32   argsz;
        __u32   flags;
+#define VFIO_DEVICE_ATTACH_PASID       (1 << 0)
        __u32   pt_id;
+       __u32   pasid;
 };
 
 #define VFIO_DEVICE_ATTACH_IOMMUFD_PT          _IO(VFIO_TYPE, VFIO_BASE + 19)
@@ -962,17 +967,21 @@ struct vfio_device_attach_iommufd_pt {
  * VFIO_DEVICE_DETACH_IOMMUFD_PT - _IOW(VFIO_TYPE, VFIO_BASE + 20,
  *                                     struct vfio_device_detach_iommufd_pt)
  * @argsz:     User filled size of this data.
- * @flags:     Must be 0.
+ * @flags:     Flags for detach.
+ * @pasid:     The pasid to be detached, only meaningful when
+ *             VFIO_DEVICE_DETACH_PASID is set in @flags
  *
- * Remove the association of the device and its current associated address
- * space.  After it, the device should be in a blocking DMA state.  This is only
- * allowed on cdev fds.
+ * Remove the association of the device or a pasid of the device and its current
+ * associated address space.  After it, the device or the pasid should be in a
+ * blocking DMA state.  This is only allowed on cdev fds.
  *
  * Return: 0 on success, -errno on failure.
  */
 struct vfio_device_detach_iommufd_pt {
        __u32   argsz;
        __u32   flags;
+#define VFIO_DEVICE_DETACH_PASID       (1 << 0)
+       __u32   pasid;
 };
 
 #define VFIO_DEVICE_DETACH_IOMMUFD_PT          _IO(VFIO_TYPE, VFIO_BASE + 20)