Commit graph

60 commits

Author SHA1 Message Date
Ulrich Drepper
170aa3d026 [PATCH] namei.c: unlock missing in error case
Signed-off-by: Ulrich Drepper <drepper@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-05 11:06:53 -08:00
Trond Myklebust
f55eab822b [PATCH] VFS: Ensure LOOKUP_CONTINUE flag is preserved by link_path_walk()
When walking a path, the LOOKUP_CONTINUE flag is used by some filesystems
(for instance NFS) in order to determine whether or not it is looking up
the last component of the path.  It this is the case, it may have to look
at the intent information in order to perform various tasks such as atomic
open.

A problem currently occurs when link_path_walk() hits a symlink.  In this
case LOOKUP_CONTINUE may be cleared prematurely when we hit the end of the
path passed by __vfs_follow_link() (i.e.  the end of the symlink path)
rather than when we hit the end of the path passed by the user.

The solution is to have link_path_walk() clear LOOKUP_CONTINUE if and only
if that flag was unset when we entered the function.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Al Viro <viro@ftp.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-05 11:06:53 -08:00
Martin Waitz
7045f37b17 [PATCH] DocBook: fix some kernel-doc comments in fs and block
Update some parameter descriptions to actually match the code.

Signed-off-by: Martin Waitz <tali@admingilde.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-01 08:53:27 -08:00
Ulrich Drepper
5590ff0d55 [PATCH] vfs: *at functions: core
Here is a series of patches which introduce in total 13 new system calls
which take a file descriptor/filename pair instead of a single file
name.  These functions, openat etc, have been discussed on numerous
occasions.  They are needed to implement race-free filesystem traversal,
they are necessary to implement a virtual per-thread current working
directory (think multi-threaded backup software), etc.

We have in glibc today implementations of the interfaces which use the
/proc/self/fd magic.  But this code is rather expensive.  Here are some
results (similar to what Jim Meyering posted before).

The test creates a deep directory hierarchy on a tmpfs filesystem.  Then
rm -fr is used to remove all directories.  Without syscall support I get
this:

real    0m31.921s
user    0m0.688s
sys     0m31.234s

With syscall support the results are much better:

real    0m20.699s
user    0m0.536s
sys     0m20.149s

The interfaces are for obvious reasons currently not much used.  But they'll
be used.  coreutils (and Jeff's posixutils) are already using them.
Furthermore, code like ftw/fts in libc (maybe even glob) will also start using
them.  I expect a patch to make follow soon.  Every program which is walking
the filesystem tree will benefit.

Signed-off-by: Ulrich Drepper <drepper@redhat.com>
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@ftp.linux.org.uk>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: Michael Kerrisk <mtk-manpages@gmx.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-18 19:20:29 -08:00
Arjan van de Ven
f16623569e [PATCH] Mark some key VFS functions as __always_inline
Mark a few VFS functions as mandatory inline (based on Al Viro's request);
these must be inline due to stack usage issues during a recursive loop that
happens during the recursive symlink resolution (symlink to a symlink to a
symlink ..)

This patch at this point does not change behavior and is for documentation
purposes only (but this changes later in the series)

Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-14 18:27:15 -08:00
Arjan van de Ven
858119e159 [PATCH] Unlinline a bunch of other functions
Remove the "inline" keyword from a bunch of big functions in the kernel with
the goal of shrinking it by 30kb to 40kb

Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Jeff Garzik <jgarzik@pobox.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-14 18:27:06 -08:00
Randy Dunlap
16f7e0fe2e [PATCH] capable/capability.h (fs/)
fs: Use <linux/capability.h> where capable() is used.

Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Acked-by: Tim Schmielau <tim@physik3.uni-rostock.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-11 18:42:13 -08:00
Jes Sorensen
1b1dcc1b57 [PATCH] mutex subsystem, semaphore to mutex: VFS, ->i_sem
This patch converts the inode semaphore to a mutex. I have tested it on
XFS and compiled as much as one can consider on an ia64. Anyway your
luck with it might be different.

Modified-by: Ingo Molnar <mingo@elte.hu>

(finished the conversion)

Signed-off-by: Jes Sorensen <jes@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2006-01-09 15:59:24 -08:00
NeilBrown
4a30131e7d [PATCH] Fix some problems with truncate and mtime semantics.
SUS requires that when truncating a file to the size that it currently
is:
  truncate and ftruncate should NOT modify ctime or mtime
  O_TRUNC SHOULD modify ctime and mtime.

Currently mtime and ctime are always modified on most local
filesystems (side effect of ->truncate) or never modified (on NFS).

With this patch:
  ATTR_CTIME|ATTR_MTIME are sent with ATTR_SIZE precisely when
    an update of these times is required whether size changes or not
    (via a new argument to do_truncate).  This allows NFS to do
    the right thing for O_TRUNC.
  inode_setattr nolonger forces ATTR_MTIME|ATTR_CTIME when the ATTR_SIZE
    sets the size to it's current value.  This allows local filesystems
    to do the right thing for f?truncate.

Also, the logic in inode_setattr is changed a bit so there are two return
points.  One returns the error from vmtruncate if it failed, the other
returns 0 (there can be no other failure).

Finally, if vmtruncate succeeds, and ATTR_SIZE is the only change
requested, we now fall-through and mark_inode_dirty.  If a filesystem did
not have a ->truncate function, then vmtruncate will have changed i_size,
without marking the inode as 'dirty', and I think this is wrong.

Signed-off-by: Neil Brown <neilb@suse.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 20:13:52 -08:00
Adrian Bunk
0ce6e62bd6 [PATCH] fs/namei.c: make path_lookup_create() static
This patch makes the needlessly global function path_lookup_create()
static.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Acked-by: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-09 07:56:40 -08:00
Christoph Hellwig
49705b7743 [PATCH] sanitize lookup_hash prototype
->permission and ->lookup have a struct nameidata * argument these days to
pass down lookup intents.  Unfortunately some callers of lookup_hash don't
actually pass this one down.  For lookup_one_len() we don't have a struct
nameidata to pass down, but as this function is a library function only
used by filesystem code this is an acceptable limitation.  All other
callers should pass down the nameidata, so this patch changes the
lookup_hash interface to only take a struct nameidata argument and derives
the other two arguments to __lookup_hash from it.  All callers already have
the nameidata argument available so this is not a problem.

At the same time I'd like to deprecate the lookup_hash interface as there
are better exported interfaces for filesystem usage.  Before it can
actually be removed I need to fix up rpc_pipefs.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Ram Pai <linuxram@us.ibm.com>
Cc: Jeff Mahoney <jeffm@suse.com>
Cc: Al Viro <viro@ftp.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-09 07:56:00 -08:00
Christoph Hellwig
8c744fb83d [PATCH] add a file_permission helper
A few more callers of permission() just want to check for a different access
pattern on an already open file.  This patch adds a wrapper for permission()
that takes a file in preparation of per-mount read-only support and to clean
up the callers a little.  The helper is not intended for new code, everything
without the interface set in stone should use vfs_permission()

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-09 07:55:59 -08:00
Christoph Hellwig
e4543eddfd [PATCH] add a vfs_permission helper
Most permission() calls have a struct nameidata * available.  This helper
takes that as an argument and thus makes sure we pass it down for lookup
intents and prepares for per-mount read-only support where we need a struct
vfsmount for checking whether a file is writeable.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-09 07:55:58 -08:00
Miklos Szeredi
cc4e69dee4 [PATCH] VFS: pass file pointer to filesystem from ftruncate()
This patch extends the iattr structure with a file pointer memeber, and adds
an ATTR_FILE validity flag for this member.

This is set if do_truncate() is invoked from ftruncate() or from
do_coredump().

The change is source and binary compatible.

Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07 07:53:42 -08:00
Miklos Szeredi
42e50a5a69 [PATCH] open: cleanup in lookup_flags()
lookup_flags() is only called from the non-create case, so it needn't check
for O_CREAT|O_EXCL.

Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Cc: Al Viro <viro@ftp.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30 17:37:18 -08:00
Trond Myklebust
cdce5d6b94 VFS: Make link_path_walk set LOOKUP_CONTINUE before calling permission().
This will allow nfs_permission() to perform additional optimizations when
 walking the path, by folding the ACCESS(MAY_EXEC) call on the directory
 into the lookup revalidation.

 Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2005-10-18 14:20:18 -07:00
Trond Myklebust
834f2a4a15 VFS: Allow the filesystem to return a full file pointer on open intent
This is needed by NFSv4 for atomicity reasons: our open command is in
 fact a lookup+open, so we need to be able to propagate open context
 information from lookup() into the resulting struct file's
 private_data field.

 Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2005-10-18 14:20:16 -07:00
Linus Torvalds
8298411468 Avoid 'names_cache' memory leak with CONFIG_AUDITSYSCALL
The nameidata "last.name" is always allocated with "__getname()", and
should always be free'd with "__putname()".

Using "putname()" without the underscores will leak memory, because the
allocation will have been hidden from the AUDITSYSCALL code.

Arguably the real bug is that the AUDITSYSCALL code is really broken,
but in the meantime this fixes the problem people see.

Reported by Robert Derr, patch by Rick Lindsley.

Acked-by: Al Viro <viro@ftp.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-06 21:54:21 -07:00
Linus Torvalds
5d54e69c68 Merge master.kernel.org:/pub/scm/linux/kernel/git/dwmw2/audit-2.6 2005-09-13 09:47:30 -07:00
Stephen Smalley
e31e14ec35 [PATCH] remove the inode_post_link and inode_post_rename LSM hooks
This patch removes the inode_post_link and inode_post_rename LSM hooks as
they are unused (and likely useless).

Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:57:28 -07:00
Stephen Smalley
a74574aafe [PATCH] Remove security_inode_post_create/mkdir/symlink/mknod hooks
This patch removes the inode_post_create/mkdir/mknod/symlink LSM hooks as
they are obsoleted by the new inode_init_security hook that enables atomic
inode security labeling.

If anyone sees any reason to retain these hooks, please speak now.  Also,
is anyone using the post_rename/link hooks; if not, those could also be
removed.

Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:57:28 -07:00
Miklos Szeredi
09dd17d3e5 [PATCH] namei cleanup
Extract common code into inline functions to make reading easier.

Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Cc: <viro@parcelfarce.linux.theplanet.co.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 16:57:42 -07:00
David Woodhouse
efda945204 Merge with master.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux-2.6.git 2005-08-27 14:30:07 +02:00
Linus Torvalds
cc314eef01 Fix nasty ncpfs symlink handling bug.
This bug could cause oopses and page state corruption, because ncpfs
used the generic page-cache symlink handlign functions.  But those
functions only work if the page cache is guaranteed to be "stable", ie a
page that was installed when the symlink walk was started has to still
be installed in the page cache at the end of the walk.

We could have fixed ncpfs to not use the generic helper routines, but it
is in many ways much cleaner to instead improve on the symlink walking
helper routines so that they don't require that absolute stability.

We do this by allowing "follow_link()" to return a error-pointer as a
cookie, which is fed back to the cleanup "put_link()" routine.  This
also simplifies NFS symlink handling.

Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-19 18:02:56 -07:00
David Woodhouse
327b6b08d6 Merge with master.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux-2.6.git 2005-08-17 14:37:55 +01:00
John McCutchan
89204c40a0 [PATCH] inotify: add MOVE_SELF event
This adds a MOVE_SELF event to inotify.  It is sent whenever the inode
you are watching is moved.  We need this event so that we can catch
something like this:

 - app1:
	watch /etc/mtab

 - app2:
	cp /etc/mtab /tmp/mtab-work
	mv /etc/mtab /etc/mtab~
	mv /tmp/mtab-work /etc/mtab

app1 still thinks it's watching /etc/mtab but it's actually watching
/etc/mtab~.

Signed-off-by: John McCutchan <ttb@tentacle.dhs.org>
Signed-off-by: Robert Love <rml@novell.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-15 09:50:31 -07:00
David Woodhouse
c973b112c7 Merge with /shiny/git/linux-2.6/.git 2005-08-09 16:51:35 +01:00
John McCutchan
7a91bf7f5c [PATCH] fsnotify_name/inoderemove
The patch below unhooks fsnotify from vfs_unlink & vfs_rmdir.  It
introduces two new fsnotify calls, that are hooked in at the dcache
level.  This not only more closely matches how the VFS layer works, it
also avoids the problem with locking and inode lifetimes.

The two functions are

 - fsnotify_nameremove -- called when a directory entry is going away.
   It notifies the PARENT of the deletion.  This is called from
   d_delete().

 - inoderemove -- called when the files inode itself is going away.  It
   notifies the inode that is being deleted.  This is called from
   dentry_iput().

Signed-off-by: John McCutchan <ttb@tentacle.dhs.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-08 11:53:47 -07:00
John McCutchan
0c3dba1534 [PATCH] Clean up inotify delete race fix
This avoids the whole #ifdef mess by just getting a copy of
dentry->d_inode before d_delete is called - that makes the codepaths the
same for the INOTIFY/DNOTIFY cases as for the regular no-notify case.
I've been running this under a Gnome session for the last 10 minutes.
Inotify is being used extensively.

Signed-off-by: John McCutchan <ttb@tentacle.dhs.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-04 21:37:39 -07:00
John McCutchan
e234f35c54 [PATCH] inotify delete race fix
The included patch fixes a problem where a inotify client would receive a
delete event before the file was actually deleted.  The bug affects both
dnotify & inotify.

Signed-off-by: John McCutchan <ttb@tentacle.dhs.org>
Signed-off-by: Robert Love <rml@novell.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-04 13:11:15 -07:00
John McCutchan
7544953685 [PATCH] inotify: fix file deletion by rename detection
When a file is moved over an existing file that you are watching,
inotify won't send you a DELETE_SELF event and it won't unref the inode
until the inotify instance is closed by the application.

Signed-off-by: John McCutchan <ttb@tentacle.dhs.org>
Signed-off-by: Robert Love <rml@novell.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-01 09:16:53 -07:00
David Woodhouse
30beab1491 Merge with /shiny/git/linux-2.6/.git 2005-07-13 15:25:59 +01:00
Robert Love
0eeca28300 [PATCH] inotify
inotify is intended to correct the deficiencies of dnotify, particularly
its inability to scale and its terrible user interface:

        * dnotify requires the opening of one fd per each directory
          that you intend to watch. This quickly results in too many
          open files and pins removable media, preventing unmount.
        * dnotify is directory-based. You only learn about changes to
          directories. Sure, a change to a file in a directory affects
          the directory, but you are then forced to keep a cache of
          stat structures.
        * dnotify's interface to user-space is awful.  Signals?

inotify provides a more usable, simple, powerful solution to file change
notification:

        * inotify's interface is a system call that returns a fd, not SIGIO.
	  You get a single fd, which is select()-able.
        * inotify has an event that says "the filesystem that the item
          you were watching is on was unmounted."
        * inotify can watch directories or files.

Inotify is currently used by Beagle (a desktop search infrastructure),
Gamin (a FAM replacement), and other projects.

See Documentation/filesystems/inotify.txt.

Signed-off-by: Robert Love <rml@novell.com>
Cc: John McCutchan <ttb@tentacle.dhs.org>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-12 20:38:38 -07:00
Miklos Szeredi
751c404b8f [PATCH] namespace: rename _mntput to mntput_no_expire
This patch renames _mntput() to something a little more descriptive:
mntput_no_expire().

Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-07 18:23:52 -07:00
David Woodhouse
d2f6409584 Merge with master.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux-2.6.git 2005-07-02 13:39:09 +01:00
Christoph Hellwig
c663e5d80e [PATCH] add some comments to lookup_create()
In a duplicate of lookup_create in the af_unix code Al commented what's
going on nicely, so let's bring that over to lookup_create before the copy
is going away (I'll send a patch soon)

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23 09:45:26 -07:00
David Woodhouse
ae7b961b1c AUDIT: Report lookup flags with path/inode records.
When LOOKUP_PARENT is used, the inode which results is not the inode
found at the pathname. Report the flags so that this doesn't generate
misleading audit records.

Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2005-06-20 16:11:05 +01:00
Al Viro
d671a1cbf7 [PATCH] namei fixes (19/19)
__do_follow_link() passes potentially worng vfsmount to touch_atime().  It
matters only in (currently impossible) case of symlink mounted on something,
but it's trivial to fix and that actually makes more sense.

Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-06 14:42:27 -07:00
Al Viro
634ee7017b [PATCH] namei fixes (18/19)
Cosmetical cleanups - __follow_mount() calls in __link_path_walk() absorbed
into do_lookup().

Obviously equivalent transformation.

Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-06 14:42:27 -07:00
Al Viro
58c465eba4 [PATCH] namei fixes (17/19)
follow_mount() made void, reordered dput()/mntput() in it.

follow_dotdot() switched from struct vfmount ** + struct dentry ** to
struct nameidata *; callers updated.

Equivalent transformation + fix for too-early-mntput() race.

Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-06 14:42:27 -07:00
Al Viro
39ca6d4975 [PATCH] namei fixes (16/19)
Conditional mntput() moved into __do_follow_link().  There it collapses with
unconditional mntget() on the same sucker, closing another too-early-mntput()
race.

Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-06 14:42:27 -07:00
Al Viro
d9d29a2966 [PATCH] namei fixes (15/19)
Getting rid of sloppy logics:

a) in do_follow_link() we have the wrong vfsmount dropped if our symlink
had been mounted on something.  Currently it worls only because we never
get such situation (modulo filesystem playing dirty tricks on us).  And
it obfuscates already convoluted logics...

b) same goes for open_namei().

c) in __link_path_walk() we have another "it should never happen" sloppiness -
out_dput: there does double-free on underlying vfsmount and leaks the covering
one if we hit it just after crossing a mountpoint.  Again, wrong vfsmount
getting dropped.

d) another too-early-mntput() race - in do_follow_mount() we need to postpone
conditional mntput(path->mnt) until after dput(path->dentry).  Again, this one
happens only in it-currently-never-happens-unless-some-fs-plays-dirty
scenario...

Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-06 14:42:27 -07:00
Al Viro
4b7b9772e4 [PATCH] namei fixes (14/19)
shifted conditional mntput() into do_follow_link() - all callers were doing
the same thing.

Obviously equivalent transformation.

Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-06 14:42:26 -07:00
Al Viro
ba7a4c1a76 [PATCH] namei fixes (13/19)
In open_namei() exit_dput: we have mntput() done in the wrong order -
if nd->mnt != path.mnt we end up doing
	mntput(nd->mnt);
	nd->mnt = path.mnt;
	dput(nd->dentry);
	mntput(nd->mnt);
which drops nd->dentry too late.  Fixed by having path.mnt go first.
That allows to switch O_NOFOLLOW under if (__follow_mount(...)) back
to exit_dput, while we are at it.

Fix for early-mntput() race + equivalent transformation.

Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-06 14:42:26 -07:00
Al Viro
a15a3f6fc6 [PATCH] namei fixes (12/19)
In open_namei() we take mntput(nd->mnt);nd->mnt=path.mnt; out of the if
(__follow_mount(...)), making it conditional on nd->mnt != path.mnt instead.

Then we shift the result downstream.

Equivalent transformations.

Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-06 14:42:26 -07:00
Al Viro
2f12dbfbb6 [PATCH] namei fixes (11/19)
shifted conditional mntput() calls in __link_path_walk() downstream.

Obviously equivalent transformation.

Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-06 14:42:26 -07:00
Al Viro
e13b210f6f [PATCH] namei fixes (10/19)
In open_namei(), __follow_down() loop turned into __follow_mount().
Instead of
	if we are on a mountpoint dentry
		if O_NOFOLLOW checks fail
			drop path.dentry
			drop nd
			return
		do equivalent of follow_mount(&path.mnt, &path.dentry)
		nd->mnt = path.mnt
we do
	if __follow_mount(path) had, indeed, traversed mountpoint
		/* now both nd->mnt and path.mnt are pinned down */
		if O_NOFOLLOW checks fail
			drop path.dentry
			drop path.mnt
			drop nd
			return
		mntput(nd->mnt)
		nd->mnt = path.mnt

Now __follow_down() can be folded into follow_down() - no other callers left.
We need to reorder dput()/mntput() there - same problem as in follow_mount().

Equivalent transformation + fix for a bug in O_NOFOLLOW handling - we used to
get -ELOOP if we had the same fs mounted on /foo and /bar, had something bound
on /bar/baz and tried to open /foo/baz with O_NOFOLLOW.  And fix of
too-early-mntput() race in follow_down()

Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-06 14:42:26 -07:00
Al Viro
463ffb2e9d [PATCH] namei fixes (9/19)
New helper: __follow_mount(struct path *path).  Same as follow_mount(), except
that we do *not* do mntput() after the first lookup_mnt().

IOW, original path->mnt stays pinned down.  We also take care to do dput()
before mntput() in the loop body (follow_mount() also needs that reordering,
but that will be done later in the series).

The following are equivalent, assuming that path.mnt == x:
(1)
	follow_mount(&path.mnt, &path.dentry)
(2)
	__follow_mount(&path);
	if (path->mnt != x)
		mntput(x);
(3)
	if (__follow_mount(&path))
		mntput(x);

Callers of follow_mount() in __link_path_walk() converted to (2).

Equivalent transformation + fix for too-late-mntput() race in __follow_mount()
loop.

Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-06 14:42:25 -07:00
Al Viro
d671d5e514 [PATCH] namei fixes (8/19)
In open_namei() we never use path.mnt or path.dentry after exit: or ok:.
Assignment of path.dentry in case of LAST_BIND is dead code and only
obfuscates already convoluted function; assignment of path.mnt after
__do_follow_link() can be moved down to the place where we set path.dentry.

Obviously equivalent transformations, just to clean the air a bit in that
region.

Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-06 14:42:25 -07:00
Al Viro
cd4e91d3bc [PATCH] namei fixes (7/19)
The first argument of __do_follow_link() switched to struct path *
(__do_follow_link(path->dentry, ...) -> __do_follow_link(path, ...)).

All callers have the same calls of mntget() right before and dput()/mntput()
right after __do_follow_link(); these calls have been moved inside.

Obviously equivalent transformations.

Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-06 14:42:25 -07:00