linux-stable.git/include/linux/namei.h, branch linux-2.6.23.y

fs: remove path_walk export

2007-07-19T17:04:45+00:00

Signed-off-by: Josef 'Jeff' Sipek 
Cc: Al Viro 
Acked-by: Christoph Hellwig 
Cc: Trond Myklebust 
Cc: Neil Brown 
Cc: Michael Halcrow 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

fs: mark link_path_walk static

2007-07-19T17:04:45+00:00

Signed-off-by: Josef 'Jeff' Sipek 
Cc: Al Viro 
Acked-by: Christoph Hellwig 
Cc: Trond Myklebust 
Cc: Neil Brown 
Cc: Michael Halcrow 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

fs: introduce vfs_path_lookup

2007-07-19T17:04:45+00:00

Stackable file systems, among others, frequently need to lookup paths or
path components starting from an arbitrary point in the namespace
(identified by a dentry and a vfsmount).  Currently, such file systems use
lookup_one_len, which is frowned upon [1] as it does not pass the lookup
intent along; not passing a lookup intent, for example, can trigger BUG_ON's
when stacking on top of NFSv4.

The first patch introduces a new lookup function to allow lookup starting
from an arbitrary point in the namespace.  This approach has been suggested
by Christoph Hellwig [2].

The second patch changes sunrpc to use vfs_path_lookup.

The third patch changes nfsctl.c to use vfs_path_lookup.

The fourth patch marks link_path_walk static.

The fifth, and last patch, unexports path_walk because it is no longer
unnecessary to call it directly, and using the new vfs_path_lookup is
cleaner.

For example, the following snippet of code, looks up "some/path/component"
in a directory pointed to by parent_{dentry,vfsmnt}:

err = vfs_path_lookup(parent_dentry, parent_vfsmnt,
		      "some/path/component", 0, &nd);
if (!err) {
	/* exits */

	...

	/* once done, release the references */
	path_release(&nd);
} else if (err == -ENOENT) {
	/* doesn't exist */
} else {
	/* other error */
}

VFS functions such as lookup_create can be used on the nameidata structure
to pass the create intent to the file system.

Signed-off-by: Josef 'Jeff' Sipek 
Cc: Al Viro 
Acked-by: Christoph Hellwig 
Cc: Trond Myklebust 
Cc: Neil Brown 
Cc: Michael Halcrow 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

security: prevent permission checking of file removal via sysfs_remove_group()

2007-04-27T17:57:33+00:00

Prevent permission checking from being performed when the kernel wants to
unconditionally remove a sysfs group, by introducing an kernel-only variant
of lookup_one_len(), lookup_one_len_kern().

Additionally, as sysfs_remove_group() does not check the return value of
the lookup before using it, a BUG_ON has been added to pinpoint the cause
of any problems potentially caused by this (and as a form of annotation).

Signed-off-by: James Morris 
Cc: Nagendra Singh Tomar 
Cc: Tejun Heo 
Cc: Stephen Smalley 
Cc: Eric Paris 
Signed-off-by: Andrew Morton 
Signed-off-by: Greg Kroah-Hartman

[PATCH] struct path: move struct path from fs/namei.c into include/linux

2006-12-08T16:28:40+00:00

Moved struct path from fs/namei.c to include/linux/namei.h.  This allows many
places in the VFS, as well as any stackable filesystem to easily keep track of
dentry-vfsmount pairs.

Signed-off-by: Josef "Jeff" Sipek 
Cc: Al Viro 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] Create fs/utimes.c

2006-10-01T07:39:19+00:00

* fs/open.c is getting bit crowdy
* preparation to lutimes(2)

Signed-off-by: Alexey Dobriyan 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] vfs: define new lookup flag for chdir

2006-09-29T16:18:08+00:00

In the "operation does permission checking" model used by fuse, chdir
permission is not checked, since there's no chdir method.

For this case set a lookup flag, which will be passed to ->permission(), so
fuse can distinguish it from permission checks for other operations.

Signed-off-by: Miklos Szeredi 
Cc: Al Viro 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] symlink nesting level change

2006-07-15T04:53:55+00:00

It's way past time to bump it to 8.  Everyone had been warned - for
months now.

RH kernels have had this for more than a year.

Signed-off-by: Al Viro 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] fs/namei.c: make lookup_hash() static

2006-03-31T20:19:01+00:00

As announced, lookup_hash() can now become static.

Signed-off-by: Adrian Bunk 
Cc: Christoph Hellwig 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] vfs: *at functions: core

2006-01-19T03:20:29+00:00

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 
Signed-off-by: Alexey Dobriyan 
Cc: Christoph Hellwig 
Cc: Al Viro 
Acked-by: Ingo Molnar 
Cc: Michael Kerrisk 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds