diff options
| -rw-r--r-- | fs/xfs/libxfs/xfs_bmap.c | 6 | ||||
| -rw-r--r-- | fs/xfs/libxfs/xfs_inode_fork.c | 16 | ||||
| -rw-r--r-- | fs/xfs/libxfs/xfs_inode_fork.h | 6 |
3 files changed, 25 insertions, 3 deletions
diff --git a/fs/xfs/libxfs/xfs_bmap.c b/fs/xfs/libxfs/xfs_bmap.c index 34de6e6898c4..f11ef331e5a4 100644 --- a/fs/xfs/libxfs/xfs_bmap.c +++ b/fs/xfs/libxfs/xfs_bmap.c @@ -1171,6 +1171,12 @@ xfs_iread_extents( goto out; } ASSERT(ir.loaded == xfs_iext_count(ifp)); + /* + * Use release semantics so that we can use acquire semantics in + * xfs_need_iread_extents and be guaranteed to see a valid mapping tree + * after that load. + */ + smp_store_release(&ifp->if_needextents, 0); return 0; out: xfs_iext_destroy(ifp); diff --git a/fs/xfs/libxfs/xfs_inode_fork.c b/fs/xfs/libxfs/xfs_inode_fork.c index 6b21760184d9..1bbe5ea3f00b 100644 --- a/fs/xfs/libxfs/xfs_inode_fork.c +++ b/fs/xfs/libxfs/xfs_inode_fork.c @@ -226,10 +226,15 @@ xfs_iformat_data_fork( /* * Initialize the extent count early, as the per-format routines may - * depend on it. + * depend on it. Use release semantics to set needextents /after/ we + * set the format. This ensures that we can use acquire semantics on + * needextents in xfs_need_iread_extents() and be guaranteed to see a + * valid format value after that load. */ ip->i_df.if_format = dip->di_format; ip->i_df.if_nextents = xfs_dfork_data_extents(dip); + smp_store_release(&ip->i_df.if_needextents, + ip->i_df.if_format == XFS_DINODE_FMT_BTREE ? 1 : 0); switch (inode->i_mode & S_IFMT) { case S_IFIFO: @@ -282,8 +287,17 @@ xfs_ifork_init_attr( enum xfs_dinode_fmt format, xfs_extnum_t nextents) { + /* + * Initialize the extent count early, as the per-format routines may + * depend on it. Use release semantics to set needextents /after/ we + * set the format. This ensures that we can use acquire semantics on + * needextents in xfs_need_iread_extents() and be guaranteed to see a + * valid format value after that load. + */ ip->i_af.if_format = format; ip->i_af.if_nextents = nextents; + smp_store_release(&ip->i_af.if_needextents, + ip->i_af.if_format == XFS_DINODE_FMT_BTREE ? 1 : 0); } void diff --git a/fs/xfs/libxfs/xfs_inode_fork.h b/fs/xfs/libxfs/xfs_inode_fork.h index d3943d6ad0b9..96d307784c85 100644 --- a/fs/xfs/libxfs/xfs_inode_fork.h +++ b/fs/xfs/libxfs/xfs_inode_fork.h @@ -24,6 +24,7 @@ struct xfs_ifork { xfs_extnum_t if_nextents; /* # of extents in this fork */ short if_broot_bytes; /* bytes allocated for root */ int8_t if_format; /* format of this fork */ + uint8_t if_needextents; /* extents have not been read */ }; /* @@ -260,9 +261,10 @@ int xfs_iext_count_upgrade(struct xfs_trans *tp, struct xfs_inode *ip, uint nr_to_add); /* returns true if the fork has extents but they are not read in yet. */ -static inline bool xfs_need_iread_extents(struct xfs_ifork *ifp) +static inline bool xfs_need_iread_extents(const struct xfs_ifork *ifp) { - return ifp->if_format == XFS_DINODE_FMT_BTREE && ifp->if_height == 0; + /* see xfs_iformat_{data,attr}_fork() for needextents semantics */ + return smp_load_acquire(&ifp->if_needextents) != 0; } #endif /* __XFS_INODE_FORK_H__ */ |