diff options
| -rw-r--r-- | fs/xfs/libxfs/xfs_iext_tree.c | 20 | ||||
| -rw-r--r-- | fs/xfs/xfs_aops.c | 4 | ||||
| -rw-r--r-- | fs/xfs/xfs_iomap.c | 3 |
3 files changed, 21 insertions, 6 deletions
diff --git a/fs/xfs/libxfs/xfs_iext_tree.c b/fs/xfs/libxfs/xfs_iext_tree.c index 8a7aea041ee1..771dd072015d 100644 --- a/fs/xfs/libxfs/xfs_iext_tree.c +++ b/fs/xfs/libxfs/xfs_iext_tree.c @@ -14,6 +14,7 @@ #include "xfs_inode_fork.h" #include "xfs_trans_resv.h" #include "xfs_mount.h" +#include "xfs_bmap.h" #include "xfs_trace.h" /* @@ -612,6 +613,19 @@ xfs_iext_realloc_root( cur->leaf = new; } +/* + * Increment the sequence counter if we are on a COW fork. This allows + * the writeback code to skip looking for a COW extent if the COW fork + * hasn't changed. We use WRITE_ONCE here to ensure the update to the + * sequence counter is seen before the modifications to the extent + * tree itself take effect. + */ +static inline void xfs_iext_inc_seq(struct xfs_ifork *ifp, int state) +{ + if (state & BMAP_COWFORK) + WRITE_ONCE(ifp->if_seq, READ_ONCE(ifp->if_seq) + 1); +} + void xfs_iext_insert( struct xfs_inode *ip, @@ -624,7 +638,7 @@ xfs_iext_insert( struct xfs_iext_leaf *new = NULL; int nr_entries, i; - ifp->if_seq++; + xfs_iext_inc_seq(ifp, state); if (ifp->if_height == 0) xfs_iext_alloc_root(ifp, cur); @@ -866,7 +880,7 @@ xfs_iext_remove( ASSERT(ifp->if_u1.if_root != NULL); ASSERT(xfs_iext_valid(ifp, cur)); - ifp->if_seq++; + xfs_iext_inc_seq(ifp, state); nr_entries = xfs_iext_leaf_nr_entries(ifp, leaf, cur->pos) - 1; for (i = cur->pos; i < nr_entries; i++) @@ -974,7 +988,7 @@ xfs_iext_update_extent( { struct xfs_ifork *ifp = xfs_iext_state_to_fork(ip, state); - ifp->if_seq++; + xfs_iext_inc_seq(ifp, state); if (cur->pos == 0) { struct xfs_bmbt_irec old; diff --git a/fs/xfs/xfs_aops.c b/fs/xfs/xfs_aops.c index 235b4ddcd324..49f5f5896a43 100644 --- a/fs/xfs/xfs_aops.c +++ b/fs/xfs/xfs_aops.c @@ -351,7 +351,7 @@ xfs_map_blocks( if (imap_valid && (!xfs_inode_has_cow_data(ip) || wpc->io_type == XFS_IO_COW || - wpc->cow_seq == ip->i_cowfp->if_seq)) + wpc->cow_seq == READ_ONCE(ip->i_cowfp->if_seq))) return 0; if (XFS_FORCED_SHUTDOWN(mp)) @@ -380,7 +380,7 @@ xfs_map_blocks( xfs_iext_lookup_extent(ip, ip->i_cowfp, offset_fsb, &icur, &imap)) cow_fsb = imap.br_startoff; if (cow_fsb != NULLFILEOFF && cow_fsb <= offset_fsb) { - wpc->cow_seq = ip->i_cowfp->if_seq; + wpc->cow_seq = READ_ONCE(ip->i_cowfp->if_seq); xfs_iunlock(ip, XFS_ILOCK_SHARED); /* * Truncate can race with writeback since writeback doesn't diff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c index 3282575e2df4..6320aca39f39 100644 --- a/fs/xfs/xfs_iomap.c +++ b/fs/xfs/xfs_iomap.c @@ -655,6 +655,7 @@ xfs_iomap_write_allocate( unsigned int *cow_seq) { xfs_mount_t *mp = ip->i_mount; + struct xfs_ifork *ifp = XFS_IFORK_PTR(ip, whichfork); xfs_fileoff_t offset_fsb, last_block; xfs_fileoff_t end_fsb, map_start_fsb; xfs_filblks_t count_fsb; @@ -768,7 +769,7 @@ xfs_iomap_write_allocate( goto error0; if (whichfork == XFS_COW_FORK) - *cow_seq = XFS_IFORK_PTR(ip, whichfork)->if_seq; + *cow_seq = READ_ONCE(ifp->if_seq); xfs_iunlock(ip, XFS_ILOCK_EXCL); } |