Ian Kent 2576737873 autofs4: use look aside list for lookups ... A while ago a patch to resolve a deadlock during directory creation was merged. This delayed the hashing of lookup dentrys until the ->mkdir() (or ->symlink()) operation completed to ensure we always went through ->lookup() instead of also having processes go through ->revalidate() so our VFS locking remained consistent. Now we are seeing a couple of side affects of that change in situations with heavy mount activity. Two cases have been identified: 1) When a mount request is triggered, due to the delayed hashing, the directory created by user space for the mount point doesn't have the DCACHE_AUTOFS_PENDING flag set. In the case of an autofs multi-mount where a tree of mount point directories are created this can lead to the path walk continuing rather than the dentry being sent to the wait queue to wait for request completion. This is because, if the pending flag isn't set, the criteria for deciding this is a mount in progress fails to hold, namely that the dentry is not a mount point and has no subdirectories. 2) A mount request dentry is initially created negative and unhashed. It remains this way until the ->mkdir() callback completes. Since it is unhashed a fresh dentry is used when the user space mount request creates the mount point directory. This leaves the original dentry negative and unhashed. But revalidate has no way to tell the VFS that the dentry has changed, other than to force another ->lookup() by returning false, which is at best wastefull and at worst not possible. This results in an -ENOENT return from the original path walk when in fact the mount succeeded. To resolve this we need to ensure that the same dentry is used in all calls to ->lookup() during the course of a mount request. This patch achieves that by adding the initial dentry to a look aside list and removes it at ->mkdir() or ->symlink() completion (or when the dentry is released), since these are the only create operations autofs4 supports. Signed-off-by: Ian Kent <raven@themaw.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2008-07-24 10:47:31 -07:00
..
9p	9p: fix O_APPEND in legacy mode	2008-07-03 09:59:03 -05:00
adfs	fs: replace remaining __FUNCTION__ occurrences	2008-04-30 08:29:54 -07:00
affs	[PATCH] fix reservation discarding in affs	2008-05-06 13:45:33 -04:00
afs	Fix various old email addresses for dwmw2	2008-06-06 11:29:10 -07:00
autofs	mount options: fix autofs	2008-02-08 09:22:40 -08:00
autofs4	autofs4: use look aside list for lookups	2008-07-24 10:47:31 -07:00
befs	byteorder: don't directly include linux/byteorder/generic.h	2008-05-16 12:01:45 -07:00
bfs	fs: replace remaining __FUNCTION__ occurrences	2008-04-30 08:29:54 -07:00
cifs	Merge commit 'v2.6.26' into bkl-removal	2008-07-14 15:29:34 -06:00
coda	device create: coda: convert device_create to device_create_drvdata	2008-07-21 21:54:41 -07:00
configfs	configfs: Allow ->make_item() and ->make_group() to return detailed errors.	2008-07-17 15:21:29 -07:00
cramfs	fs: Remove unnecessary inclusions of asm/semaphore.h	2008-04-18 22:16:44 -04:00
debugfs	debugfs: Implement debugfs_remove_recursive()	2008-07-21 21:54:59 -07:00
devpts	devpts: factor out PTY index allocation	2008-04-30 08:29:48 -07:00
dlm	configfs: Allow ->make_item() and ->make_group() to return detailed errors.	2008-07-17 15:21:29 -07:00
ecryptfs	eCryptfs: Make all persistent file opens delayed	2008-07-24 10:47:31 -07:00
efs	efs: update error msg to not refer to deleted read_inode()	2008-04-02 15:28:19 -07:00
exportfs	fs: replace remaining __FUNCTION__ occurrences	2008-04-30 08:29:54 -07:00
ext2	ext2: retry block allocation if new blocks are allocated from system zone	2008-04-28 08:58:43 -07:00
ext3	ext3: add missing unlock to error path in ext3_quota_write()	2008-07-04 10:40:05 -07:00
ext4	ext4: do not set extents feature from the kernel	2008-07-11 19:27:31 -04:00
fat	Merge commit 'v2.6.26' into bkl-removal	2008-07-14 15:29:34 -06:00
freevxfs	fs/freevxfs/: proper externs	2008-04-29 08:06:00 -07:00
fuse	fuse: fix thinko in max I/O size calucation	2008-06-17 18:08:10 -07:00
gfs2	Merge git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-2.6-nmw	2008-07-15 10:38:46 -07:00
hfs	hfs: fix warning with 64k PAGE_SIZE	2008-04-30 08:29:52 -07:00
hfsplus	Fix hfsplus oops on image without extents	2008-05-13 08:02:24 -07:00
hostfs	uml: fix hostfs tv_usec calculations	2008-02-05 09:44:30 -08:00
hpfs	mount options: fix hpfs	2008-02-08 09:22:40 -08:00
hppfs	fix hppfs Makefile breakage	2008-05-21 16:55:58 -07:00
hugetlbfs	hugetlbfs: per mount huge page sizes	2008-07-24 10:47:17 -07:00
isofs	isofs: fix access to unallocated memory when reading corrupted filesystem	2008-04-30 08:29:33 -07:00
jbd	jbd: need to hold j_state_lock to updates to transaction t_state to T_COMMIT	2008-05-14 19:11:14 -07:00
jbd2	ext4: Add ordered mode support for delalloc	2008-07-11 19:27:31 -04:00
jffs2	Merge git://git.infradead.org/mtd-2.6	2008-05-01 11:15:28 -07:00
jfs	jfs: remove DIRENTSIZ	2008-06-10 15:12:58 -05:00
lockd	Merge branch 'for-2.6.27' of git://linux-nfs.org/~bfields/linux	2008-07-20 21:21:46 -07:00
minix	iget: stop the MINIX filesystem from using iget() and read_inode()	2008-02-07 08:42:28 -08:00
msdos	Replace BKL with superblock lock in fat/msdos/vfat	2008-06-20 14:05:54 -06:00
ncpfs	Remove BKL from remote_llseek v2	2008-07-02 15:06:27 -06:00
nfs	Merge branch 'bkl-removal' into next	2008-07-15 18:34:58 -04:00
nfs_common
nfsd	Merge branch 'for-2.6.27' of git://linux-nfs.org/~bfields/linux	2008-07-20 21:21:46 -07:00
nls
ntfs	ntfs: le*_add_cpu conversion	2008-05-24 09:56:08 -07:00
ocfs2	configfs: Allow ->make_item() and ->make_group() to return detailed errors.	2008-07-17 15:21:29 -07:00
openpromfs	iget: stop OPENPROMFS from using iget() and read_inode()	2008-02-07 08:42:29 -08:00
partitions	driver core: remove KOBJ_NAME_LEN define	2008-07-21 21:54:52 -07:00
proc	vmallocinfo: add NUMA information	2008-07-24 10:47:17 -07:00
qnx4	iget: stop QNX4 from using iget() and read_inode()	2008-02-07 08:42:28 -08:00
ramfs	ramfs: enable splice write	2008-07-04 09:52:14 +02:00
reiserfs	reiserfs: discard prealloc in reiserfs_delete_inode	2008-07-08 12:39:31 -07:00
romfs	ROMFS: Fix up an error in iget removal	2008-03-19 18:53:36 -07:00
smbfs	Remove BKL from remote_llseek v2	2008-07-02 15:06:27 -06:00
sysfs	driver core: Suppress sysfs warnings for device_rename().	2008-07-21 21:55:01 -07:00
sysv	sysv: [bl]e*_add_cpu conversion	2008-04-30 08:29:52 -07:00
ubifs	UBIFS: include to compilation	2008-07-15 17:35:24 +03:00
udf	udf: Fix regression in UDF anchor block detection	2008-06-24 11:38:03 +02:00
ufs	ufs: remove unneeded ufs_put_inode prototype	2008-05-13 08:02:23 -07:00
vfat	Replace BKL with superblock lock in fat/msdos/vfat	2008-06-20 14:05:54 -06:00
xfs	Fix reference counting race on log buffers	2008-07-11 11:37:18 -07:00
aio.c	uml: activate_mm: remove the dead PF_BORROWED_MM check	2008-06-06 11:36:22 -07:00
anon_inodes.c	flag parameters: NONBLOCK in anon_inode_getfd	2008-07-24 10:47:28 -07:00
attr.c
bad_inode.c	iget: introduce a function to register iget failure	2008-02-07 08:42:26 -08:00
binfmt_aout.c	fs/binfmt_aout.c: use printk_ratelimit()	2008-04-29 08:06:04 -07:00
binfmt_elf_fdpic.c	nommu: fix ksize() abuse	2008-06-06 11:29:13 -07:00
binfmt_elf.c	execve filename: document and export via auxiliary vector	2008-07-22 09:59:40 -07:00
binfmt_em86.c	binfmt_misc.c: avoid potential kernel stack overflow	2008-04-29 08:06:04 -07:00
binfmt_flat.c	nommu: fix ksize() abuse	2008-06-06 11:29:13 -07:00
binfmt_misc.c	binfmt_misc: use simple_read_from_buffer()	2008-07-24 10:47:27 -07:00
binfmt_script.c	binfmt_misc.c: avoid potential kernel stack overflow	2008-04-29 08:06:04 -07:00
binfmt_som.c	[PATCH] sanitize handling of shared descriptor tables in failing execve()	2008-04-25 09:23:53 -04:00
bio-integrity.c	block: integrity checkpatch cleanups	2008-07-03 13:21:13 +02:00
bio.c	Add bvec_merge_data to handle stacked devices and ->merge_bvec()	2008-07-03 13:21:15 +02:00
block_dev.c	[PATCH] fix cgroup-inflicted breakage in block_dev.c	2008-06-23 08:30:55 -04:00
buffer.c	Merge branch 'generic-ipi' into generic-ipi-for-linus	2008-07-15 21:55:59 +02:00
char_dev.c	Remove the lock_kernel() call from chrdev_open()	2008-06-20 14:05:53 -06:00
compat_binfmt_elf.c	x86: compat_binfmt_elf	2008-01-30 13:31:46 +01:00
compat_ioctl.c	Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/holtmann/bluetooth-2.6	2008-07-19 00:30:39 -07:00
compat.c	flag parameters: signalfd	2008-07-24 10:47:27 -07:00
dcache.c	fix soft lock up at NFS mount via per-SB LRU-list of unused dentries	2008-07-24 10:47:15 -07:00
dcookies.c	d_path: Make d_path() use a struct path	2008-02-14 21:17:09 -08:00
direct-io.c	Pagecache zeroing: zero_user_segment, zero_user_segments and zero_user	2008-02-05 09:44:13 -08:00
dnotify.c	[PATCH] split linux/file.h	2008-05-01 13:08:16 -04:00
dquot.c	quota: don't call sync_fs() from vfs_quota_off() when there's no quota turn off	2008-05-13 08:02:23 -07:00
drop_caches.c	vfs: skip inodes without pages to free in drop_pagecache_sb()	2008-04-29 08:06:05 -07:00
eventfd.c	flag parameters: check magic constants	2008-07-24 10:47:29 -07:00
eventpoll.c	flag parameters add-on: remove epoll_create size param	2008-07-24 10:47:29 -07:00
exec.c	mm: remove double indirection on tlb parameter to free_pgd_range() & Co	2008-07-24 10:47:15 -07:00
fcntl.c	flag parameters: dup2	2008-07-24 10:47:28 -07:00
fifo.c
file_table.c	[PATCH] split linux/file.h	2008-05-01 13:08:16 -04:00
file.c	[PATCH] avoid multiplication overflows and signedness issues for max_fds	2008-05-16 17:22:52 -04:00
filesystems.c
fs-writeback.c	VFS: export sync_sb_inodes	2008-07-14 19:10:52 +03:00
generic_acl.c
inode.c	VFS: fix unused variable warning	2008-05-06 13:13:37 -07:00
inotify_user.c	flag parameters: check magic constants	2008-07-24 10:47:29 -07:00
inotify.c	inotify: remove debug code	2008-02-06 10:41:07 -08:00
internal.h	[PATCH] move a bunch of declarations to fs/internal.h	2008-04-21 23:11:01 -04:00
ioctl.c	make vfs_ioctl() static	2008-04-29 08:06:00 -07:00
ioprio.c	cfq-iosched: relax IOPRIO_CLASS_IDLE restrictions	2008-01-28 11:38:15 +01:00
Kconfig	Merge branch 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mfasheh/ocfs2	2008-07-17 10:55:51 -07:00
Kconfig.binfmt	frv: don't offer BINFMT_FLAT	2008-06-06 11:29:08 -07:00
libfs.c	add kernel-doc for simple_read_from_buffer and memory_read_from_buffer	2008-07-04 10:40:07 -07:00
locks.c	[patch 4/4] flock: remove unused fields from file_lock_operations	2008-06-23 11:52:30 -04:00
Makefile	Merge branch 'for_linus' of git://git.infradead.org/~dedekind/ubifs-2.6	2008-07-16 15:02:57 -07:00
mbcache.c	vfs: fix possible deadlock in ext2, ext3, ext4 when using xattrs	2008-04-15 19:35:41 -07:00
mpage.c	vfs: add hooks for ext4's delayed allocation support	2008-07-11 19:27:31 -04:00
namei.c	[patch 3/4] vfs: fix ERR_PTR abuse in generic_readlink	2008-06-23 11:52:30 -04:00
namespace.c	LSM/SELinux: show LSM mount options in /proc/mounts	2008-07-14 15:02:05 +10:00
nfsctl.c	Introduce path_put()	2008-02-14 21:13:33 -08:00
no-block.c
open.c	fs: check for statfs overflow	2008-07-24 10:47:19 -07:00
pipe.c	flag parameters: NONBLOCK in pipe	2008-07-24 10:47:29 -07:00
pnode.c	[patch 7/7] vfs: mountinfo: show dominating group id	2008-04-23 00:05:09 -04:00
pnode.h	[patch 7/7] vfs: mountinfo: show dominating group id	2008-04-23 00:05:09 -04:00
posix_acl.c
quota_v1.c	quota: do not allow setting of quota limits to too high values	2008-04-28 08:58:32 -07:00
quota_v2.c	quota: le*_add_cpu conversion	2008-04-30 08:29:51 -07:00
quota.c	quota: quota core changes for quotaon on remount	2008-04-28 08:58:33 -07:00
read_write.c	Remove BKL from remote_llseek v2	2008-07-02 15:06:27 -06:00
read_write.h
readdir.c	Use mutex_lock_killable in vfs_readdir	2007-12-06 17:39:54 -05:00
select.c	Fix performance regression on lmbench select benchmark	2008-06-22 12:23:15 -07:00
seq_file.c	[patch 2/7] vfs: mountinfo: add seq_file_root()	2008-04-23 00:04:38 -04:00
signalfd.c	flag parameters: check magic constants	2008-07-24 10:47:29 -07:00
splice.c	splice: fix generic_file_splice_read() race with page invalidation	2008-07-04 09:52:14 +02:00
stack.c
stat.c	Introduce path_put()	2008-02-14 21:13:33 -08:00
super.c	fix soft lock up at NFS mount via per-SB LRU-list of unused dentries	2008-07-24 10:47:15 -07:00
sync.c	SYNC_FILE_RANGE_WRITE may and will block. Document that.	2008-07-24 10:47:17 -07:00
timerfd.c	flag parameters: check magic constants	2008-07-24 10:47:29 -07:00
utimes.c	[patch for 2.6.26 4/4] vfs: utimensat(): fix write access check for futimens()	2008-06-23 08:43:52 -04:00
xattr_acl.c
xattr.c	xattr: add missing consts to function arguments	2008-04-29 08:06:06 -07:00