xen/blkback: Convert to bdev_open_by_dev()

Convert xen/blkback to use bdev_open_by_dev() and pass the
handle around.

CC: xen-devel@lists.xenproject.org
Acked-by: Christoph Hellwig <hch@lst.de>
Acked-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20230927093442.25915-7-jack@suse.czSigned-off-by: Christian Brauner <brauner@kernel.org>

drivers/block/xen-blkback/blkback.c

@@ -465,7 +465,7 @@ static int xen_vbd_translate(struct phys_req *req, struct xen_blkif *blkif,
 	}
 
 	req->dev  = vbd->pdevice;
-	req->bdev = vbd->bdev;
+	req->bdev = vbd->bdev_handle->bdev;
 	rc = 0;
 
  out:
@@ -969,7 +969,7 @@ static int dispatch_discard_io(struct xen_blkif_ring *ring,
 	int err = 0;
 	int status = BLKIF_RSP_OKAY;
 	struct xen_blkif *blkif = ring->blkif;
-	struct block_device *bdev = blkif->vbd.bdev;
+	struct block_device *bdev = blkif->vbd.bdev_handle->bdev;
 	struct phys_req preq;
 
 	xen_blkif_get(blkif);

drivers/block/xen-blkback/common.h

@@ -221,7 +221,7 @@ struct xen_vbd {
 	unsigned char		type;
 	/* phys device that this vbd maps to. */
 	u32			pdevice;
-	struct block_device	*bdev;
+	struct bdev_handle	*bdev_handle;
 	/* Cached size parameter. */
 	sector_t		size;
 	unsigned int		flush_support:1;
@@ -360,7 +360,7 @@ struct pending_req {
 };
 
 
-#define vbd_sz(_v)	bdev_nr_sectors((_v)->bdev)
+#define vbd_sz(_v)	bdev_nr_sectors((_v)->bdev_handle->bdev)
 
 #define xen_blkif_get(_b) (atomic_inc(&(_b)->refcnt))
 #define xen_blkif_put(_b)				\

drivers/block/xen-blkback/xenbus.c

@@ -81,7 +81,7 @@ static void xen_update_blkif_status(struct xen_blkif *blkif)
 	int i;
 
 	/* Not ready to connect? */
-	if (!blkif->rings || !blkif->rings[0].irq || !blkif->vbd.bdev)
+	if (!blkif->rings || !blkif->rings[0].irq || !blkif->vbd.bdev_handle)
 		return;
 
 	/* Already connected? */
@@ -99,12 +99,13 @@ static void xen_update_blkif_status(struct xen_blkif *blkif)
 		return;
 	}
 
-	err = sync_blockdev(blkif->vbd.bdev);
+	err = sync_blockdev(blkif->vbd.bdev_handle->bdev);
 	if (err) {
 		xenbus_dev_error(blkif->be->dev, err, "block flush");
 		return;
 	}
-	invalidate_inode_pages2(blkif->vbd.bdev->bd_inode->i_mapping);
+	invalidate_inode_pages2(
+			blkif->vbd.bdev_handle->bdev->bd_inode->i_mapping);
 
 	for (i = 0; i < blkif->nr_rings; i++) {
 		ring = &blkif->rings[i];
@@ -472,9 +473,9 @@ static void xenvbd_sysfs_delif(struct xenbus_device *dev)
 
 static void xen_vbd_free(struct xen_vbd *vbd)
 {
-	if (vbd->bdev)
-		blkdev_put(vbd->bdev, NULL);
-	vbd->bdev = NULL;
+	if (vbd->bdev_handle)
+		bdev_release(vbd->bdev_handle);
+	vbd->bdev_handle = NULL;
 }
 
 static int xen_vbd_create(struct xen_blkif *blkif, blkif_vdev_t handle,
@@ -482,7 +483,7 @@ static int xen_vbd_create(struct xen_blkif *blkif, blkif_vdev_t handle,
 			  int cdrom)
 {
 	struct xen_vbd *vbd;
-	struct block_device *bdev;
+	struct bdev_handle *bdev_handle;
 
 	vbd = &blkif->vbd;
 	vbd->handle   = handle;
@@ -491,17 +492,17 @@ static int xen_vbd_create(struct xen_blkif *blkif, blkif_vdev_t handle,
 
 	vbd->pdevice  = MKDEV(major, minor);
 
-	bdev = blkdev_get_by_dev(vbd->pdevice, vbd->readonly ?
+	bdev_handle = bdev_open_by_dev(vbd->pdevice, vbd->readonly ?
 				 BLK_OPEN_READ : BLK_OPEN_WRITE, NULL, NULL);
 
-	if (IS_ERR(bdev)) {
+	if (IS_ERR(bdev_handle)) {
 		pr_warn("xen_vbd_create: device %08x could not be opened\n",
 			vbd->pdevice);
 		return -ENOENT;
 	}
 
-	vbd->bdev = bdev;
-	if (vbd->bdev->bd_disk == NULL) {
+	vbd->bdev_handle = bdev_handle;
+	if (vbd->bdev_handle->bdev->bd_disk == NULL) {
 		pr_warn("xen_vbd_create: device %08x doesn't exist\n",
 			vbd->pdevice);
 		xen_vbd_free(vbd);
@@ -509,14 +510,14 @@ static int xen_vbd_create(struct xen_blkif *blkif, blkif_vdev_t handle,
 	}
 	vbd->size = vbd_sz(vbd);
 
-	if (cdrom || disk_to_cdi(vbd->bdev->bd_disk))
+	if (cdrom || disk_to_cdi(vbd->bdev_handle->bdev->bd_disk))
 		vbd->type |= VDISK_CDROM;
-	if (vbd->bdev->bd_disk->flags & GENHD_FL_REMOVABLE)
+	if (vbd->bdev_handle->bdev->bd_disk->flags & GENHD_FL_REMOVABLE)
 		vbd->type |= VDISK_REMOVABLE;
 
-	if (bdev_write_cache(bdev))
+	if (bdev_write_cache(bdev_handle->bdev))
 		vbd->flush_support = true;
-	if (bdev_max_secure_erase_sectors(bdev))
+	if (bdev_max_secure_erase_sectors(bdev_handle->bdev))
 		vbd->discard_secure = true;
 
 	pr_debug("Successful creation of handle=%04x (dom=%u)\n",
@@ -569,7 +570,7 @@ static void xen_blkbk_discard(struct xenbus_transaction xbt, struct backend_info
 	struct xen_blkif *blkif = be->blkif;
 	int err;
 	int state = 0;
-	struct block_device *bdev = be->blkif->vbd.bdev;
+	struct block_device *bdev = be->blkif->vbd.bdev_handle->bdev;
 
 	if (!xenbus_read_unsigned(dev->nodename, "discard-enable", 1))
 		return;
@@ -930,15 +931,16 @@ static void connect(struct backend_info *be)
 		goto abort;
 	}
 	err = xenbus_printf(xbt, dev->nodename, "sector-size", "%lu",
-			    (unsigned long)
-			    bdev_logical_block_size(be->blkif->vbd.bdev));
+			    (unsigned long)bdev_logical_block_size(
+					be->blkif->vbd.bdev_handle->bdev));
 	if (err) {
 		xenbus_dev_fatal(dev, err, "writing %s/sector-size",
 				 dev->nodename);
 		goto abort;
 	}
 	err = xenbus_printf(xbt, dev->nodename, "physical-sector-size", "%u",
-			    bdev_physical_block_size(be->blkif->vbd.bdev));
+			    bdev_physical_block_size(
+					be->blkif->vbd.bdev_handle->bdev));
 	if (err)
 		xenbus_dev_error(dev, err, "writing %s/physical-sector-size",
 				 dev->nodename);