Commit c86537a4 authored by Goldwyn Rodrigues's avatar Goldwyn Rodrigues Committed by David Sterba
Browse files

btrfs: check FS error state bit early during write 



fs_info::fs_state is a filesystem bit check as opposed to inode and can
be performed before we begin with write checks. This eliminates inode
lock/unlock in case the error bit is set.

Reviewed-by: default avatarJosef Bacik <josef@toxicpanda.com>
Signed-off-by: default avatarGoldwyn Rodrigues <rgoldwyn@suse.com>
Reviewed-by: default avatarDavid Sterba <dsterba@suse.com>
Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent 5e8b9ef3

fs/btrfs/file.c

+8 −12
Original line number Diff line number Diff line
@@ -1907,6 +1907,14 @@ static ssize_t btrfs_file_write_iter(struct kiocb *iocb, 
	size_t count;

	loff_t oldsize;



	/*

	 * If the fs flips readonly due to some impossible error, although we

	 * have opened a file as writable, we have to stop this write operation

	 * to ensure consistency.

	 */

	if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state))

		return -EROFS;



	if (!(iocb->ki_flags & IOCB_DIRECT) &&

	    (iocb->ki_flags & IOCB_NOWAIT))

		return -EOPNOTSUPP;
@@ -1956,18 +1964,6 @@ static ssize_t btrfs_file_write_iter(struct kiocb *iocb, 
		goto out;

	}



	/*

	 * If BTRFS flips readonly due to some impossible error

	 * (fs_info->fs_state now has BTRFS_SUPER_FLAG_ERROR),

	 * although we have opened a file as writable, we have

	 * to stop this write operation to ensure FS consistency.

	 */

	if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state)) {

		inode_unlock(inode);

		err = -EROFS;

		goto out;

	}



	/*

	 * We reserve space for updating the inode when we reserve space for the

	 * extent we are going to write, so we will enospc out there.  We don't