diff options
Diffstat (limited to 'fs/xfs/xfs_trans.c')
| -rw-r--r-- | fs/xfs/xfs_trans.c | 39 |
1 files changed, 24 insertions, 15 deletions
diff --git a/fs/xfs/xfs_trans.c b/fs/xfs/xfs_trans.c index f5969c8274fc..2011620008de 100644 --- a/fs/xfs/xfs_trans.c +++ b/fs/xfs/xfs_trans.c @@ -263,6 +263,28 @@ xfs_trans_alloc( } /* + * Create an empty transaction with no reservation. This is a defensive + * mechanism for routines that query metadata without actually modifying + * them -- if the metadata being queried is somehow cross-linked (think a + * btree block pointer that points higher in the tree), we risk deadlock. + * However, blocks grabbed as part of a transaction can be re-grabbed. + * The verifiers will notice the corrupt block and the operation will fail + * back to userspace without deadlocking. + * + * Note the zero-length reservation; this transaction MUST be cancelled + * without any dirty data. + */ +int +xfs_trans_alloc_empty( + struct xfs_mount *mp, + struct xfs_trans **tpp) +{ + struct xfs_trans_res resv = {0}; + + return xfs_trans_alloc(mp, &resv, 0, 0, XFS_TRANS_NO_WRITECOUNT, tpp); +} + +/* * Record the indicated change to the given field for application * to the file system's superblock when the transaction commits. * For now, just store the change in the transaction structure. @@ -1012,17 +1034,14 @@ xfs_trans_cancel( * chunk we've been working on and get a new transaction to continue. */ int -__xfs_trans_roll( +xfs_trans_roll( struct xfs_trans **tpp, - struct xfs_inode *dp, - int *committed) + struct xfs_inode *dp) { struct xfs_trans *trans; struct xfs_trans_res tres; int error; - *committed = 0; - /* * Ensure that the inode is always logged. */ @@ -1048,7 +1067,6 @@ __xfs_trans_roll( if (error) return error; - *committed = 1; trans = *tpp; /* @@ -1071,12 +1089,3 @@ __xfs_trans_roll( xfs_trans_ijoin(trans, dp, 0); return 0; } - -int -xfs_trans_roll( - struct xfs_trans **tpp, - struct xfs_inode *dp) -{ - int committed; - return __xfs_trans_roll(tpp, dp, &committed); -} |