diff --git a/fs/xfs/xfs_dfrag.c b/fs/xfs/xfs_dfrag.c index 760f4c5b5160..75b0cd4da0ea 100644 --- a/fs/xfs/xfs_dfrag.c +++ b/fs/xfs/xfs_dfrag.c @@ -149,7 +149,14 @@ xfs_swap_extents( sbp = &sxp->sx_stat; - xfs_lock_two_inodes(ip, tip, lock_flags); + /* + * we have to do two separate lock calls here to keep lockdep + * happy. If we try to get all the locks in one call, lock will + * report false positives when we drop the ILOCK and regain them + * below. + */ + xfs_lock_two_inodes(ip, tip, XFS_IOLOCK_EXCL); + xfs_lock_two_inodes(ip, tip, XFS_ILOCK_EXCL); locked = 1; /* Verify that both files have the same format */ diff --git a/fs/xfs/xfs_vnodeops.c b/fs/xfs/xfs_vnodeops.c index aa238c8fbd7a..98a0aecafddc 100644 --- a/fs/xfs/xfs_vnodeops.c +++ b/fs/xfs/xfs_vnodeops.c @@ -1838,6 +1838,12 @@ again: #endif } +/* + * xfs_lock_two_inodes() can only be used to lock one type of lock + * at a time - the iolock or the ilock, but not both at once. If + * we lock both at once, lockdep will report false positives saying + * we have violated locking orders. + */ void xfs_lock_two_inodes( xfs_inode_t *ip0, @@ -1848,6 +1854,8 @@ xfs_lock_two_inodes( int attempts = 0; xfs_log_item_t *lp; + if (lock_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL)) + ASSERT((lock_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)) == 0); ASSERT(ip0->i_ino != ip1->i_ino); if (ip0->i_ino > ip1->i_ino) {