diff options
Diffstat (limited to 'fs/xfs/xfs_aops.c')
| -rw-r--r-- | fs/xfs/xfs_aops.c | 38 |
1 files changed, 28 insertions, 10 deletions
diff --git a/fs/xfs/xfs_aops.c b/fs/xfs/xfs_aops.c index 561cf1456c6c..ab266d66124d 100644 --- a/fs/xfs/xfs_aops.c +++ b/fs/xfs/xfs_aops.c @@ -777,7 +777,7 @@ xfs_map_cow( { struct xfs_inode *ip = XFS_I(inode); struct xfs_bmbt_irec imap; - bool is_cow = false, need_alloc = false; + bool is_cow = false; int error; /* @@ -795,7 +795,7 @@ xfs_map_cow( * Else we need to check if there is a COW mapping at this offset. */ xfs_ilock(ip, XFS_ILOCK_SHARED); - is_cow = xfs_reflink_find_cow_mapping(ip, offset, &imap, &need_alloc); + is_cow = xfs_reflink_find_cow_mapping(ip, offset, &imap); xfs_iunlock(ip, XFS_ILOCK_SHARED); if (!is_cow) @@ -805,7 +805,7 @@ xfs_map_cow( * And if the COW mapping has a delayed extent here we need to * allocate real space for it now. */ - if (need_alloc) { + if (isnullstartblock(imap.br_startblock)) { error = xfs_iomap_write_allocate(ip, XFS_COW_FORK, offset, &imap); if (error) @@ -1311,7 +1311,6 @@ __xfs_get_blocks( ssize_t size; int new = 0; bool is_cow = false; - bool need_alloc = false; BUG_ON(create && !direct); @@ -1337,9 +1336,11 @@ __xfs_get_blocks( end_fsb = XFS_B_TO_FSB(mp, (xfs_ufsize_t)offset + size); offset_fsb = XFS_B_TO_FSBT(mp, offset); - if (create && direct && xfs_is_reflink_inode(ip)) - is_cow = xfs_reflink_find_cow_mapping(ip, offset, &imap, - &need_alloc); + if (create && direct && xfs_is_reflink_inode(ip)) { + is_cow = xfs_reflink_find_cow_mapping(ip, offset, &imap); + ASSERT(!is_cow || !isnullstartblock(imap.br_startblock)); + } + if (!is_cow) { error = xfs_bmapi_read(ip, offset_fsb, end_fsb - offset_fsb, &imap, &nimaps, XFS_BMAPI_ENTIRE); @@ -1356,10 +1357,29 @@ __xfs_get_blocks( xfs_reflink_trim_irec_to_next_cow(ip, offset_fsb, &imap); } - ASSERT(!need_alloc); if (error) goto out_unlock; + /* + * The only time we can ever safely find delalloc blocks on direct I/O + * is a dio write to post-eof speculative preallocation. All other + * scenarios are indicative of a problem or misuse (such as mixing + * direct and mapped I/O). + * + * The file may be unmapped by the time we get here so we cannot + * reliably fail the I/O based on mapping. Instead, fail the I/O if this + * is a read or a write within eof. Otherwise, carry on but warn as a + * precuation if the file happens to be mapped. + */ + if (direct && imap.br_startblock == DELAYSTARTBLOCK) { + if (!create || offset < i_size_read(VFS_I(ip))) { + WARN_ON_ONCE(1); + error = -EIO; + goto out_unlock; + } + WARN_ON_ONCE(mapping_mapped(VFS_I(ip)->i_mapping)); + } + /* for DAX, we convert unwritten extents directly */ if (create && (!nimaps || @@ -1444,8 +1464,6 @@ __xfs_get_blocks( (new || ISUNWRITTEN(&imap)))) set_buffer_new(bh_result); - BUG_ON(direct && imap.br_startblock == DELAYSTARTBLOCK); - return 0; out_unlock: |