linux/fs
Zach Brown 6d544bb4d9 [PATCH] dio: centralize completion in dio_complete()
There have been a lot of bugs recently due to the way direct_io_worker() tries
to decide how to finish direct IO operations.  In the worst examples it has
failed to call aio_complete() at all (hang) or called it too many times
(oops).

This set of patches cleans up the completion phase with the goal of removing
the complexity that lead to these bugs.  We end up with one path that
calculates the result of the operation after all off the bios have completed.
We decide when to generate a result of the operation using that path based on
the final release of a refcount on the dio structure.

I tried to progress towards the final state in steps that were relatively easy
to understand.  Each step should compile but I only tested the final result of
having all the patches applied.

I've tested these on low end PC drives with aio-stress, the direct IO tests I
could manage to get running in LTP, orasim, and some home-brew functional
tests.

In http://lkml.org/lkml/2006/9/21/103 IBM reports success with ext2 and ext3
running DIO LTP tests.  They found that XFS bug which has since been addressed
in the patch series.

This patch:

The mechanics which decide the result of a direct IO operation were duplicated
in the sync and async paths.

The async path didn't check page_errors which can manifest as silently
returning success when the final pointer in an operation faults and its
matching file region is filled with zeros.

The sync path and async path differed in whether they passed errors to the
caller's dio->end_io operation.  The async path was passing errors to it which
trips an assertion in XFS, though it is apparently harmless.

This centralizes the completion phase of dio ops in one place.  AIO will now
return EFAULT consistently and all paths fall back to the previously sync
behaviour of passing the number of bytes 'transferred' to the dio->end_io
callback, regardless of errors.

dio_await_completion() doesn't have to propogate EIO from non-uptodate bios
now that it's being propogated through dio_complete() via dio->io_error.  This
lets it return void which simplifies its sole caller.

Signed-off-by: Zach Brown <zach.brown@oracle.com>
Cc: Badari Pulavarty <pbadari@us.ibm.com>
Cc: Suparna Bhattacharya <suparna@in.ibm.com>
Acked-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-10 09:57:21 -08:00
..
9p [PATCH] 9p: change uses of f_{dentry,vfsmnt} to use f_path 2006-12-08 08:28:43 -08:00
adfs [PATCH] struct path: convert adfs 2006-12-08 08:28:43 -08:00
affs [PATCH] affs: change uses of f_{dentry, vfsmnt} to use f_path 2006-12-08 08:28:43 -08:00
afs [PATCH] rename struct namespace to struct mnt_namespace 2006-12-08 08:28:51 -08:00
autofs [PATCH] autofs: change uses of f_{dentry, vfsmnt} to use f_path 2006-12-08 08:28:43 -08:00
autofs4 [PATCH] autofs4: change uses of f_{dentry, vfsmnt} to use f_path 2006-12-08 08:28:43 -08:00
befs [PATCH] struct path: convert befs 2006-12-08 08:28:44 -08:00
bfs [PATCH] struct path: convert bfs 2006-12-08 08:28:44 -08:00
cifs [PATCH] io-accounting-read-accounting cifs fix 2006-12-10 09:55:41 -08:00
coda [PATCH] struct path: convert coda 2006-12-08 08:28:44 -08:00
configfs [PATCH] configfs: change uses of f_{dentry, vfsmnt} to use f_path 2006-12-08 08:28:43 -08:00
cramfs [PATCH] struct path: convert cramfs 2006-12-08 08:28:44 -08:00
debugfs [PATCH] debugfs: add header file 2006-11-25 13:28:33 -08:00
devpts [PATCH] inode-diet: Eliminate i_blksize from the inode structure 2006-09-27 08:26:18 -07:00
dlm Merge master.kernel.org:/pub/scm/linux/kernel/git/steve/gfs2-2.6-nmw 2006-12-07 09:13:20 -08:00
ecryptfs [PATCH] ecryptfs: change uses of f_{dentry, vfsmnt} to use f_path 2006-12-08 08:28:43 -08:00
efs [PATCH] struct path: convert efs 2006-12-08 08:28:45 -08:00
exportfs [PATCH] VFS: Make filldir_t and struct kstat deal in 64-bit inode numbers 2006-10-03 08:03:40 -07:00
ext2 [PATCH] LOG2: Implement a general integer log2 facility in the kernel 2006-12-08 08:28:51 -08:00
ext3 [PATCH] LOG2: Implement a general integer log2 facility in the kernel 2006-12-08 08:28:51 -08:00
ext4 [PATCH] ext4: change uses of f_{dentry, vfsmnt} to use f_path 2006-12-08 08:28:41 -08:00
fat [PATCH] fat: change uses of f_{dentry,vfsmnt} to use f_path 2006-12-08 08:28:41 -08:00
freevxfs [PATCH] struct path: convert freevxfs 2006-12-08 08:28:45 -08:00
fuse [PATCH] struct path: convert fuse 2006-12-08 08:28:45 -08:00
gfs2 [PATCH] struct path: convert gfs2 2006-12-08 08:28:45 -08:00
hfs [PATCH] struct path: convert hfs 2006-12-08 08:28:45 -08:00
hfsplus [PATCH] struct path: convert hfsplus 2006-12-08 08:28:45 -08:00
hostfs [PATCH] struct path: convert hostfs 2006-12-08 08:28:45 -08:00
hpfs [PATCH] struct path: convert hpfs 2006-12-08 08:28:45 -08:00
hppfs [PATCH] struct path: convert hppfs 2006-12-08 08:28:45 -08:00
hugetlbfs [PATCH] struct path: convert hugetlbfs 2006-12-08 08:28:45 -08:00
isofs [PATCH] isofs: change uses of f_{dentry, vfsmnt} to use f_path 2006-12-08 08:28:41 -08:00
jbd [PATCH] make fs/jbd/transaction.c:__journal_temp_unlink_buffer() static 2006-12-07 08:39:40 -08:00
jbd2 [PATCH] jbd2: wait for already submitted t_sync_datalist buffer to complete 2006-12-07 08:39:42 -08:00
jffs [PATCH] struct path: convert jffs 2006-12-08 08:28:46 -08:00
jffs2 [PATCH] struct path: convert jffs2 2006-12-08 08:28:46 -08:00
jfs [PATCH] struct path: convert jfs 2006-12-08 08:28:46 -08:00
lockd [PATCH] struct path: convert lockd 2006-12-08 08:28:47 -08:00
minix [PATCH] struct path: convert minix 2006-12-08 08:28:47 -08:00
msdos [PATCH] fat: add fat_getattr() 2006-11-16 11:43:38 -08:00
ncpfs [PATCH] struct path: convert ncpfs 2006-12-08 08:28:48 -08:00
nfs [PATCH] rename struct namespace to struct mnt_namespace 2006-12-08 08:28:51 -08:00
nfs_common [PATCH] nfs_common endianness annotations 2006-10-20 10:26:41 -07:00
nfsd [PATCH] nfsd: replace kmalloc+memset with kcalloc + simplify NULL check 2006-12-08 08:29:02 -08:00
nls [PATCH] fs: make nls_cp936.c handle some U00XY characters and U20AC correctly 2006-12-07 08:39:46 -08:00
ntfs [PATCH] ntfs: change uses of f_{dentry, vfsmnt} to use f_path 2006-12-08 08:28:42 -08:00
ocfs2 [PATCH] struct path: convert ocfs2 2006-12-08 08:28:48 -08:00
openpromfs [PATCH] struct path: convert openpromfs 2006-12-08 08:28:48 -08:00
partitions [MIPS] Rename SNI_RM200_PCI to just SNI_RM preparing for more RM machines 2006-12-09 01:03:58 +00:00
proc [PATCH] io-accounting: report in procfs 2006-12-10 09:55:41 -08:00
qnx4 [PATCH] struct path: convert qnx4 2006-12-08 08:28:48 -08:00
ramfs [PATCH] struct path: convert ramfs 2006-12-08 08:28:49 -08:00
reiserfs [PATCH] rename struct namespace to struct mnt_namespace 2006-12-08 08:28:51 -08:00
romfs [PATCH] struct path: convert romfs 2006-12-08 08:28:49 -08:00
smbfs [PATCH] struct path: convert smbfs 2006-12-08 08:28:49 -08:00
sysfs [PATCH] sysfs: change uses of f_{dentry, vfsmnt} to use f_path 2006-12-08 08:28:41 -08:00
sysv [PATCH] struct path: convert sysv 2006-12-08 08:28:50 -08:00
udf [PATCH] struct path: convert udf 2006-12-08 08:28:50 -08:00
ufs [PATCH] struct path: convert ufs 2006-12-08 08:28:50 -08:00
vfat [PATCH] fat: add fat_getattr() 2006-11-16 11:43:38 -08:00
xfs [PATCH] xfs: change uses of f_{dentry,vfsmnt} to use f_path 2006-12-08 08:28:43 -08:00
aio.c [PATCH] aio: remove ki_retried debugging member 2006-12-07 08:39:46 -08:00
attr.c [PATCH] capable/capability.h (fs/) 2006-01-11 18:42:13 -08:00
bad_inode.c [PATCH] Remove readv/writev methods and use aio_read/aio_write instead 2006-10-01 00:39:28 -07:00
binfmt_aout.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
binfmt_elf_fdpic.c [PATCH] add process_session() helper routine 2006-12-08 08:28:51 -08:00
binfmt_elf.c [PATCH] add process_session() helper routine 2006-12-08 08:28:51 -08:00
binfmt_em86.c
binfmt_flat.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
binfmt_misc.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
binfmt_script.c
binfmt_som.c [PARISC] Fix fs/binfmt_som.c 2006-10-04 06:51:26 -06:00
bio.c [PATCH] slab: remove kmem_cache_t 2006-12-07 08:39:25 -08:00
block_dev.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
buffer.c [PATCH] io-accounting: write-cancel accounting 2006-12-10 09:55:41 -08:00
char_dev.c [PATCH] BLOCK: Move extern declarations out of fs/*.c into header files [try #6] 2006-09-30 20:52:18 +02:00
compat_ioctl.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
compat.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
dcache.c [PATCH] dcache: avoid RCU for never-hashed dentries 2006-12-07 08:39:41 -08:00
dcookies.c [PATCH] slab: remove kmem_cache_t 2006-12-07 08:39:25 -08:00
direct-io.c [PATCH] dio: centralize completion in dio_complete() 2006-12-10 09:57:21 -08:00
dnotify.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
dquot.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
drop_caches.c [PATCH] drop-pagecache 2006-01-08 20:12:40 -08:00
eventpoll.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
exec.c [PATCH] add child reaper to pid_namespace 2006-12-08 08:28:52 -08:00
fcntl.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
fifo.c [PATCH] pipe.c/fifo.c code cleanups 2006-04-11 13:53:33 +02:00
file_table.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
file.c [PATCH] file: kill unnecessary timer in fdtable_defer 2006-12-07 08:39:32 -08:00
filesystems.c [PATCH] Ban register_filesystem(NULL); 2006-09-29 09:18:20 -07:00
fs-writeback.c [PATCH] BLOCK: Remove dependence on existence of blockdev_superblock [try #6] 2006-09-30 20:52:26 +02:00
generic_acl.c [PATCH] Generic infrastructure for acls 2006-09-29 09:18:24 -07:00
inode.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
inotify_user.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
inotify.c [PATCH] severing fs.h, radix-tree.h -> sched.h 2006-12-04 02:00:24 -05:00
internal.h [PATCH] CONFIG_BLOCK internal.h cleanups 2006-09-30 20:52:32 +02:00
ioctl.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
ioprio.c [PATCH] block layer: ioprio_best function fix 2006-10-12 15:09:51 +02:00
Kconfig Fix typos in doc and comments 2006-11-30 05:32:19 +01:00
Kconfig.binfmt [PATCH] frv: suppress configuration of certain features for FRV 2006-01-08 20:13:36 -08:00
libfs.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
locks.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
Makefile [PATCH] fsstack: Introduce fsstack_copy_{attr,inode}_* 2006-12-08 08:28:40 -08:00
mbcache.c [PATCH] slab: remove kmem_cache_t 2006-12-07 08:39:25 -08:00
mpage.c [PATCH] BLOCK: Dissociate generic_writepages() from mpage stuff [try #6] 2006-09-30 20:52:26 +02:00
namei.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
namespace.c [PATCH] rename struct namespace to struct mnt_namespace 2006-12-08 08:28:51 -08:00
nfsctl.c Remove obsolete #include <linux/config.h> 2006-06-30 19:25:36 +02:00
no-block.c [PATCH] BLOCK: Make it possible to disable the block layer [try #6] 2006-09-30 20:52:31 +02:00
open.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
pipe.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
pnode.c [PATCH] rename struct namespace to struct mnt_namespace 2006-12-08 08:28:51 -08:00
pnode.h [PATCH] rename struct namespace to struct mnt_namespace 2006-12-08 08:28:51 -08:00
posix_acl.c [PATCH] kmemdup: some users 2006-10-01 00:39:19 -07:00
quota_v1.c
quota_v2.c [PATCH] sem2mutex: quota 2006-03-23 07:38:11 -08:00
quota.c [PATCH] BLOCK: Make it possible to disable the block layer [try #6] 2006-09-30 20:52:31 +02:00
read_write.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
read_write.h [PATCH] Remove readv/writev methods and use aio_read/aio_write instead 2006-10-01 00:39:28 -07:00
readdir.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
select.c [PATCH] enforce RLIMIT_NOFILE in poll() 2006-09-29 09:18:23 -07:00
seq_file.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
splice.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
stack.c [PATCH] fsstack: Introduce fsstack_copy_{attr,inode}_* 2006-12-08 08:28:40 -08:00
stat.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
super.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
sync.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
utimes.c [PATCH] severing fs.h, radix-tree.h -> sched.h 2006-12-04 02:00:24 -05:00
xattr_acl.c
xattr.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00