diff options
| -rw-r--r-- | fs/xfs/xfs_fsmap.c | 14 |
1 files changed, 5 insertions, 9 deletions
diff --git a/fs/xfs/xfs_fsmap.c b/fs/xfs/xfs_fsmap.c index 9ce5e7d5bf8f..34f2b971ce43 100644 --- a/fs/xfs/xfs_fsmap.c +++ b/fs/xfs/xfs_fsmap.c @@ -904,14 +904,6 @@ xfs_getfsmap( info.fsmap_recs = fsmap_recs; info.head = head; - /* - * If fsmap runs concurrently with a scrub, the freeze can be delayed - * indefinitely as we walk the rmapbt and iterate over metadata - * buffers. Freeze quiesces the log (which waits for the buffer LRU to - * be emptied) and that won't happen while we're reading buffers. - */ - sb_start_write(mp->m_super); - /* For each device we support... */ for (i = 0; i < XFS_GETFSMAP_DEVS; i++) { /* Is this device within the range the user asked for? */ @@ -934,6 +926,11 @@ xfs_getfsmap( if (handlers[i].dev > head->fmh_keys[0].fmr_device) memset(&dkeys[0], 0, sizeof(struct xfs_fsmap)); + /* + * Grab an empty transaction so that we can use its recursive + * buffer locking abilities to detect cycles in the rmapbt + * without deadlocking. + */ error = xfs_trans_alloc_empty(mp, &tp); if (error) break; @@ -951,7 +948,6 @@ xfs_getfsmap( if (tp) xfs_trans_cancel(tp); - sb_end_write(mp->m_super); head->fmh_oflags = FMH_OF_DEV_T; return error; } |