linux/fs/xfs/linux-2.6
Lachlan McIlroy 364f358a73 [XFS] Prevent direct I/O from mapping extents beyond eof
With the help from some tracing I found that we try to map extents beyond
eof when doing a direct I/O read. It appears that the way to inform the
generic direct I/O path (ie do_direct_IO()) that we have breached eof is
to return an unmapped buffer from xfs_get_blocks_direct(). This will cause
do_direct_IO() to jump to the hole handling code where is will check for
eof and then abort.

This problem was found because a direct I/O read was trying to map beyond
eof and was encountering delayed allocations. The delayed allocations
beyond eof are speculative allocations and they didn't get converted when
the direct I/O flushed the file because there was only enough space in the
current AG to convert and write out the dirty pages within eof. Note that
xfs_iomap_write_allocate() wont necessarily convert all the delayed
allocation passed to it - it will return after allocating the first extent
- so if the delayed allocation extends beyond eof then it will stay that
way.

SGI-PV: 983683

SGI-Modid: xfs-linux-melb:xfs-kern:31929a

Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
2008-09-17 16:50:14 +10:00
..
kmem.c [XFS] kmem_free and kmem_realloc to use const void * 2008-07-28 16:58:43 +10:00
kmem.h [XFS] kmem_free and kmem_realloc to use const void * 2008-07-28 16:58:43 +10:00
mrlock.h [XFS] shrink mrlock_t 2008-04-29 15:54:02 +10:00
mutex.h
sv.h
time.h
xfs_aops.c [XFS] Prevent direct I/O from mapping extents beyond eof 2008-09-17 16:50:14 +10:00
xfs_aops.h [XFS] move v_iocount from bhv_vnode to xfs_inode 2007-10-16 11:38:56 +10:00
xfs_buf.c [XFS] Use KM_NOFS for debug trace buffers 2008-08-13 16:51:57 +10:00
xfs_buf.h [XFS] replace the XFS buf iodone semaphore with a completion 2008-08-13 16:36:11 +10:00
xfs_cred.h [XFS] Replace __inline with inline 2008-04-18 11:51:15 +10:00
xfs_dmapi_priv.h [XFS] Remove KERNEL_VERSION macros from xfs_dmapi.h 2006-11-11 18:05:06 +11:00
xfs_export.c [XFS] convert xfs to use ERR_CAST 2008-08-13 16:09:25 +10:00
xfs_export.h xfs: new export ops 2007-10-22 08:13:20 -07:00
xfs_file.c [PATCH] fix ->llseek() for a bunch of directories 2008-08-25 01:18:09 -04:00
xfs_fs_subr.c [XFS] Avoid directly referencing the VFS inode. 2008-08-13 15:45:15 +10:00
xfs_fs_subr.h [XFS] decontaminate vnode operations from behavior details 2007-10-15 16:54:29 +10:00
xfs_globals.c [XFS] Fix up sparse warnings. 2008-02-07 18:14:38 +11:00
xfs_globals.h [XFS] Remove xfs_physmem 2007-10-15 16:40:14 +10:00
xfs_ioctl32.c [XFS] Fix up sparse warnings. 2008-02-07 18:14:38 +11:00
xfs_ioctl32.h
xfs_ioctl.c [XFS] Kill shouty XFS_ITOV() macro 2008-08-13 16:00:45 +10:00
xfs_iops.c [PATCH] change d_add_ci argument ordering 2008-08-25 01:18:05 -04:00
xfs_iops.h [XFS] stop using file_update_time 2008-08-13 16:48:12 +10:00
xfs_linux.h CRED: Introduce credential access wrappers 2008-08-14 09:35:23 +10:00
xfs_lrw.c [XFS] stop using file_update_time 2008-08-13 16:48:12 +10:00
xfs_lrw.h [XFS] remove sendfile leftovers 2008-04-29 16:08:14 +10:00
xfs_stats.c [XFS] streamline init/exit path 2008-07-28 16:59:25 +10:00
xfs_stats.h [XFS] fix compilation without CONFIG_PROC_FS 2008-07-28 16:59:31 +10:00
xfs_super.c [XFS] Fix regression introduced by remount fixup 2008-09-17 16:49:33 +10:00
xfs_super.h [XFS] sanitize xfs_initialize_vnode 2008-08-13 16:23:13 +10:00
xfs_sysctl.c [XFS] streamline init/exit path 2008-07-28 16:59:25 +10:00
xfs_sysctl.h [XFS] streamline init/exit path 2008-07-28 16:59:25 +10:00
xfs_version.h
xfs_vfs.h [XFS] Remove periodic logging of in-core superblock counters. 2008-04-18 12:03:12 +10:00
xfs_vnode.c [XFS] clean up stale references to semaphores 2008-08-13 16:34:31 +10:00
xfs_vnode.h [XFS] kill bhv_vnode_t 2008-08-13 16:22:40 +10:00
xfs_xattr.c [XFS] Remove vn_revalidate calls in xfs. 2008-07-28 16:59:39 +10:00