block: introduce holder ops

Add a new blk_holder_ops structure, which is passed to blkdev_get_by_* and
installed in the block_device for exclusive claims.  It will be used to
allow the block layer to call back into the user of the block device for
thing like notification of a removed device or a device resize.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Link: https://lore.kernel.org/r/20230601094459.1350643-10-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Christoph Hellwig
2023-06-01 11:44:52 +02:00
committed by Jens Axboe
parent 00080f7fb7
commit 0718afd47f
34 changed files with 90 additions and 56 deletions

View File

@@ -2770,7 +2770,8 @@ static int claim_swapfile(struct swap_info_struct *p, struct inode *inode)
if (S_ISBLK(inode->i_mode)) {
p->bdev = blkdev_get_by_dev(inode->i_rdev,
FMODE_READ | FMODE_WRITE | FMODE_EXCL, p);
FMODE_READ | FMODE_WRITE | FMODE_EXCL, p,
NULL);
if (IS_ERR(p->bdev)) {
error = PTR_ERR(p->bdev);
p->bdev = NULL;