make set_blocksize() fail unless block device is opened exclusive

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro 2024-05-02 17:36:32 -04:00
parent ead083aeee
commit d18a867958
2 changed files with 10 additions and 0 deletions

View File

@ -1134,3 +1134,10 @@ superblock of the main block device, i.e., the one stored in sb->s_bdev. Block
device freezing now works for any block device owned by a given superblock, not
just the main block device. The get_active_super() helper and bd_fsfreeze_sb
pointer are gone.
---
**mandatory**
set_blocksize() takes opened struct file instead of struct block_device now
and it *must* be opened exclusive.

View File

@ -157,6 +157,9 @@ int set_blocksize(struct file *file, int size)
if (size < bdev_logical_block_size(bdev))
return -EINVAL;
if (!file->private_data)
return -EINVAL;
/* Don't change the size if it is same as current */
if (inode->i_blkbits != blksize_bits(size)) {
sync_blockdev(bdev);