diff options
Diffstat (limited to 'fs/xfs/xfs_discard.c')
| -rw-r--r-- | fs/xfs/xfs_discard.c | 17 |
1 files changed, 16 insertions, 1 deletions
diff --git a/fs/xfs/xfs_discard.c b/fs/xfs/xfs_discard.c index c1a306268ae4..94d0873bcd62 100644 --- a/fs/xfs/xfs_discard.c +++ b/fs/xfs/xfs_discard.c @@ -167,6 +167,14 @@ xfs_discard_extents( return error; } +/* + * Care must be taken setting up the trim cursor as the perags may not have been + * initialised when the cursor is initialised. e.g. a clean mount which hasn't + * read in AGFs and the first operation run on the mounted fs is a trim. This + * can result in perag fields that aren't initialised until + * xfs_trim_gather_extents() calls xfs_alloc_read_agf() to lock down the AG for + * the free space search. + */ struct xfs_trim_cur { xfs_agblock_t start; xfs_extlen_t count; @@ -204,6 +212,14 @@ xfs_trim_gather_extents( if (error) goto out_trans_cancel; + /* + * First time through tcur->count will not have been initialised as + * pag->pagf_longest is not guaranteed to be valid before we read + * the AGF buffer above. + */ + if (!tcur->count) + tcur->count = pag->pagf_longest; + if (tcur->by_bno) { /* sub-AG discard request always starts at tcur->start */ cur = xfs_bnobt_init_cursor(mp, tp, agbp, pag); @@ -350,7 +366,6 @@ xfs_trim_perag_extents( { struct xfs_trim_cur tcur = { .start = start, - .count = pag->pagf_longest, .end = end, .minlen = minlen, }; |