[PATCH 07/29] xen/blkback: Convert to bdev_open_by_dev()

[Jan Kara <jack@xxxxxxx>]

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

CC: xen-devel@xxxxxxxxxxxxxxxxxxxx
Acked-by: Christoph Hellwig <hch@xxxxxx>
Signed-off-by: Jan Kara <jack@xxxxxxx>
---
 drivers/block/xen-blkback/blkback.c |  4 +--
 drivers/block/xen-blkback/common.h  |  4 +--
 drivers/block/xen-blkback/xenbus.c  | 40 +++++++++++++++--------------
 3 files changed, 25 insertions(+), 23 deletions(-)

diff --git a/drivers/block/xen-blkback/blkback.c 
b/drivers/block/xen-blkback/blkback.c
index c362f4ad80ab..4defd7f387c7 100644
--- a/drivers/block/xen-blkback/blkback.c
+++ b/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);
diff --git a/drivers/block/xen-blkback/common.h 
b/drivers/block/xen-blkback/common.h
index 40f67bfc052d..5ff50e76cee5 100644
--- a/drivers/block/xen-blkback/common.h
+++ b/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)                              \
diff --git a/drivers/block/xen-blkback/xenbus.c 
b/drivers/block/xen-blkback/xenbus.c
index bb66178c432b..e34219ea2b05 100644
--- a/drivers/block/xen-blkback/xenbus.c
+++ 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);
-- 
2.35.3