Commit ccaaca25 authored Oct 08, 2013 by Jaegeuk Kim

f2fs: fix writing incorrect orphan blocks



Previously, there was a erroneous scenario like below.
thread 1:                       thread 2:
 f2fs_unlink
  - acquire_orphan_inode
    : sbi->n_orphans++           write_checkpoint
                                 - block_operations
                                  : f2fs_lock_all
                                 - do_checkpoint
                                  : write orphan blocks with sbi->n_orphans
                                 - unblock_operations
  - f2fs_lock_op
  - release_orphan_inode
  - f2fs_unlock_op

During the checkpoint by thread 2, f2fs stores a wrong orphan block according
to the wrong sbi->n_orphans.
To avoid this, simply we should make cover acquire_orphan_inode too with
f2fs_lock_op.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>

parent 5887d291

fs/f2fs/namei.c

+2 −2

Original line number	Original line	Diff line number	Diff line
	@@ -228,14 +228,14 @@ static int f2fs_unlink(struct inode dir, struct dentry dentry)
	if (!de)		if (!de)
	goto fail;		goto fail;

			f2fs_lock_op(sbi);
	err = acquire_orphan_inode(sbi);		err = acquire_orphan_inode(sbi);
	if (err) {		if (err) {
			f2fs_unlock_op(sbi);
	kunmap(page);		kunmap(page);
	f2fs_put_page(page, 0);		f2fs_put_page(page, 0);
	goto fail;		goto fail;
	}		}

	f2fs_lock_op(sbi);
	f2fs_delete_entry(de, page, inode);		f2fs_delete_entry(de, page, inode);
	f2fs_unlock_op(sbi);		f2fs_unlock_op(sbi);