Commit Graph

206 Commits

Author SHA1 Message Date
Al Viro
1f707137b5 new helper: iterate_mounts()
apply function to vfsmounts in set returned by collect_mounts(),
stop if it returns non-zero.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-03-03 14:07:57 -05:00
Valerie Aurora
495d6c9c65 VFS: Clean up shared mount flag propagation
The handling of mount flags in set_mnt_shared() got a little tangled
up during previous cleanups, with the following problems:

* MNT_PNODE_MASK is defined as a literal constant when it should be a
bitwise xor of other MNT_* flags
* set_mnt_shared() clears and then sets MNT_SHARED (part of MNT_PNODE_MASK)
* MNT_PNODE_MASK could use a comment in mount.h
* MNT_PNODE_MASK is a terrible name, change to MNT_SHARED_MASK

This patch fixes these problems.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-03-03 14:07:55 -05:00
Al Viro
796a6b521d Kill CL_PROPAGATION, sanitize fs/pnode.c:get_source()
First of all, get_source() never results in CL_PROPAGATION
alone.  We either get CL_MAKE_SHARED (for the continuation
of peer group) or CL_SLAVE (slave that is not shared) or both
(beginning of peer group among slaves).  Massage the code to
make that explicit, kill CL_PROPAGATION test in clone_mnt()
(nothing sets CL_MAKE_SHARED without CL_PROPAGATION and in
clone_mnt() we are checking CL_PROPAGATION after we'd found
that there's no CL_SLAVE, so the check for CL_MAKE_SHARED
would do just as well).

Fix comments, while we are at it...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-03-03 13:00:22 -05:00
Al Viro
27d55f1f4c do_add_mount() should sanitize mnt_flags
MNT_WRITE_HOLD shouldn't leak into new vfsmount and neither
should MNT_SHARED (the latter will be set properly, along with
the rest of shared-subtree data structures)

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-01-16 13:07:36 -05:00
Al Viro
7b43a79f32 mnt_flags fixes in do_remount()
* need vfsmount_lock over modifying it
* need to preserve MNT_SHARED/MNT_UNBINDABLE

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-01-16 13:01:26 -05:00
Al Viro
df1a1ad297 attach_recursive_mnt() needs to hold vfsmount_lock over set_mnt_shared()
race in mnt_flags update

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-01-16 12:57:40 -05:00
Al Viro
8ad08d8a0c may_umount() needs namespace_sem
otherwise it races with clone_mnt() changing mnt_share/mnt_slaves

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-01-16 12:56:08 -05:00
Linus Torvalds
a2770d86b3 Revert "fix mismerge with Trond's stuff (create_mnt_ns() export is gone now)"
This reverts commit e9496ff46a. Quoth Al:

 "it's dependent on a lot of other stuff not currently in mainline
  and badly broken with current fs/namespace.c.  Sorry, badly
  out-of-order cherry-pick from old queue.

  PS: there's a large pending series reworking the refcounting and
  lifetime rules for vfsmounts that will, among other things, allow to
  rip a subtree away _without_ dissolving connections in it, to be
  garbage-collected when all active references are gone.  It's
  considerably saner wrt "is the subtree busy" logics, but it's nowhere
  near being ready for merge at the moment; this changeset is one of the
  things becoming possible with that sucker, but it certainly shouldn't
  have been picked during this cycle.  My apologies..."

Noticed-by: Eric Paris <eparis@redhat.com>
Requested-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-17 12:51:05 -08:00
Al Viro
e9496ff46a fix mismerge with Trond's stuff (create_mnt_ns() export is gone now)
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-12-16 12:16:44 -05:00
Tetsuo Handa
a27ab9f26b LSM: Pass original mount flags to security_sb_mount().
This patch allows LSM modules to determine based on original mount flags
passed to mount(). A LSM module can get masked mount flags (if needed) by

	flags &= ~(MS_NOSUID | MS_NOEXEC | MS_NODEV | MS_ACTIVE |
		   MS_NOATIME | MS_NODIRATIME | MS_RELATIME| MS_KERNMOUNT |
		   MS_STRICTATIME);

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2009-10-12 10:56:03 +11:00
Vegard Nossum
eca6f534e6 fs: fix overflow in sys_mount() for in-kernel calls
sys_mount() reads/copies a whole page for its "type" parameter.  When
do_mount_root() passes a kernel address that points to an object which is
smaller than a whole page, copy_mount_options() will happily go past this
memory object, possibly dereferencing "wild" pointers that could be in any
state (hence the kmemcheck warning, which shows that parts of the next
page are not even allocated).

(The likelihood of something going wrong here is pretty low -- first of
all this only applies to kernel calls to sys_mount(), which are mostly
found in the boot code.  Secondly, I guess if the page was not mapped,
exact_copy_from_user() _would_ in fact handle it correctly because of its
access_ok(), etc.  checks.)

But it is much nicer to avoid the dubious reads altogether, by stopping as
soon as we find a NUL byte.  Is there a good reason why we can't do
something like this, using the already existing strndup_from_user()?

[akpm@linux-foundation.org: make copy_mount_string() static]
[AV: fix compat mount breakage, which involves undoing akpm's change above]

Reported-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: al <al@dizzy.pdmi.ras.ru>
2009-09-24 08:40:15 -04:00
OGAWA Hirofumi
2d8dd38a5a vfs: mnt_want_write_file(): fix special file handling
I suspect that mnt_want_write_file() may have wrong assumption.  I think
mnt_want_write_file() is assuming it increments ->mnt_writers if
(file->f_mode & FMODE_WRITE).  But, if it's special_file(), it is false?

Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Acked-by: Dave Hansen <dave@linux.vnet.ibm.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-08-07 10:39:56 -07:00
Alexey Dobriyan
b43f3cbd21 headers: mnt_namespace.h redux
Fix various silly problems wrt mnt_namespace.h:

 - exit_mnt_ns() isn't used, remove it
 - done that, sched.h and nsproxy.h inclusions aren't needed
 - mount.h inclusion was need for vfsmount_lock, but no longer
 - remove mnt_namespace.h inclusion from files which don't use anything
   from mnt_namespace.h

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-07-08 09:31:56 -07:00
Al Viro
f21f62208a ... and the same for vfsmount id/mount group id
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-24 08:15:26 -04:00
Trond Myklebust
3b22edc573 VFS: Switch init_mount_tree() to use the new create_mnt_ns() helper
Eliminates some duplicated code...

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-24 08:15:24 -04:00
Trond Myklebust
cf8d2c11cb VFS: Add VFS helper functions for setting up private namespaces
The purpose of this patch is to improve the remote mount path lookup
support for distributed filesystems such as the NFSv4 client.

When given a mount command of the form "mount server:/foo/bar /mnt", the
NFSv4 client is required to look up the filehandle for "server:/", and
then look up each component of the remote mount path "foo/bar" in order
to find the directory that is actually going to be mounted on /mnt.
Following that remote mount path may involve following symlinks,
crossing server-side mount points and even following referrals to
filesystem volumes on other servers.

Since the standard VFS path lookup code already supports walking paths
that contain all these features (using in-kernel automounts for
following referrals) we would like to be able to reuse that rather than
duplicate the full path traversal functionality in the NFSv4 client code.

This patch therefore defines a VFS helper function create_mnt_ns(), that
sets up a temporary filesystem namespace and attaches a root filesystem to
it. It exports the create_mnt_ns() and put_mnt_ns() function for use by
filesystem modules.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-22 21:28:25 -07:00
Trond Myklebust
616511d039 VFS: Uninline the function put_mnt_ns()
In order to allow modules to use it without having to export vfsmount_lock.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-22 21:28:25 -07:00
Al Viro
4aa98cf768 Push BKL down into do_remount_sb()
[folded fix from Jiri Slaby]

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-11 21:36:08 -04:00
Al Viro
7f78d4cd4c Push BKL down beyond VFS-only parts of do_mount()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-11 21:36:08 -04:00
Al Viro
6fac98dd21 Push BKL into do_mount()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-11 21:36:08 -04:00
Alexey Dobriyan
f3da392e9f dcache: extrace and use d_unlinked()
d_unlinked() will be used in middle-term to ban checkpointing when opened
but unlinked file is detected, and in long term, to detect such situation
and special case on it.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-11 21:36:06 -04:00
npiggin@suse.de
96029c4e09 fs: introduce mnt_clone_write
This patch speeds up lmbench lat_mmap test by about another 2% after the
first patch.

Before:
 avg = 462.286
 std = 5.46106

After:
 avg = 453.12
 std = 9.58257

(50 runs of each, stddev gives a reasonable confidence)

It does this by introducing mnt_clone_write, which avoids some heavyweight
operations of mnt_want_write if called on a vfsmount which we know already
has a write count; and mnt_want_write_file, which can call mnt_clone_write
if the file is open for write.

After these two patches, mnt_want_write and mnt_drop_write go from 7% on
the profile down to 1.3% (including mnt_clone_write).

[AV: mnt_want_write_file() should take file alone and derive mnt from it;
not only all callers have that form, but that's the only mnt about which
we know that it's already held for write if file is opened for write]

Cc: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-11 21:36:02 -04:00
npiggin@suse.de
d3ef3d7351 fs: mnt_want_write speedup
This patch speeds up lmbench lat_mmap test by about 8%. lat_mmap is set up
basically to mmap a 64MB file on tmpfs, fault in its pages, then unmap it.
A microbenchmark yes, but it exercises some important paths in the mm.

Before:
 avg = 501.9
 std = 14.7773

After:
 avg = 462.286
 std = 5.46106

(50 runs of each, stddev gives a reasonable confidence, but there is quite
a bit of variation there still)

It does this by removing the complex per-cpu locking and counter-cache and
replaces it with a percpu counter in struct vfsmount. This makes the code
much simpler, and avoids spinlocks (although the msync is still pretty
costly, unfortunately). It results in about 900 bytes smaller code too. It
does increase the size of a vfsmount, however.

It should also give a speedup on large systems if CPUs are frequently operating
on different mounts (because the existing scheme has to operate on an atomic in
the struct vfsmount when switching between mounts). But I'm most interested in
the single threaded path performance for the moment.

[AV: minor cleanup]

Cc: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-11 21:36:02 -04:00
Al Viro
1c755af4df switch lookup_mnt()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-11 21:36:01 -04:00
Al Viro
9393bd07cf switch follow_down()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-11 21:36:01 -04:00
Al Viro
589ff870ed Switch collect_mounts() to struct path
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-11 21:36:01 -04:00
Al Viro
dd5cae6e97 Don't bother with check_mnt() in do_add_mount() on shrinkable ones
These guys are what we add as submounts; checks for "is that attached in
our namespace" are simply irrelevant for those and counterproductive for
use of private vfsmount trees a-la what NFS folks want.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-11 21:35:59 -04:00
Al Viro
2a32cebd6c Fix races around the access to ->s_options
Put generic_show_options read access to s_options under rcu_read_lock,
split save_mount_options() into "we are setting it the first time"
(uses in foo_fill_super()) and "we are relacing and freeing the old one",
synchronize_rcu() before kfree() in the latter.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-05-09 10:51:34 -04:00
Alessio Igor Bogani
67e55205ec vfs: umount_begin BKL pushdown
Push BKL down into ->umount_begin()

Signed-off-by: Alessio Igor Bogani <abogani@texware.it>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-05-09 10:49:38 -04:00
Al Viro
e5d67f0715 Touch all affected namespaces on propagation of mount
We shouldn't just touch the namespace of current process

Caught-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-04-20 23:01:15 -04:00
Andi Kleen
613cbe3d48 Don't set relatime when noatime is specified
Since commit 0a1c01c947 ("Make relatime
default") when a file system is mounted explicitely with noatime it gets
both the MNT_RELATIME and MNT_NOATIME bits set.

This shows up like this in /proc/mounts:

  /dev/xxx /yyy ext3 rw,noatime,relatime,errors=continue,data=writeback 0 0

That looks strange.  The VFS uses noatime in this case, but both flags
are set.  So it's more a cosmetic issue, but still better to fix.

Cc: mjg@redhat.com
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-19 10:46:47 -07:00
Al Viro
5ad4e53bd5 Get rid of indirect include of fs_struct.h
Don't pull it in sched.h; very few files actually need it and those
can include directly.  sched.h itself only needs forward declaration
of struct fs_struct;

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-03-31 23:00:27 -04:00
Al Viro
3e93cd6718 Take fs_struct handling to new file (fs/fs_struct.c)
Pure code move; two new helper functions for nfsd and daemonize
(unshare_fs_struct() and daemonize_fs_struct() resp.; for now -
the same code as used to be in callers).  unshare_fs_struct()
exported (for nfsd, as copy_fs_struct()/exit_fs() used to be),
copy_fs_struct() and exit_fs() don't need exports anymore.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-03-31 23:00:26 -04:00
Al Viro
f8ef3ed2be Get rid of bumping fs_struct refcount in pivot_root(2)
Not because execve races with _that_ are serious - we really
need a situation when final drop of fs_struct refcount is
done by something that used to have it as current->fs.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-03-31 23:00:25 -04:00
Linus Torvalds
3ae5080f4c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (37 commits)
  fs: avoid I_NEW inodes
  Merge code for single and multiple-instance mounts
  Remove get_init_pts_sb()
  Move common mknod_ptmx() calls into caller
  Parse mount options just once and copy them to super block
  Unroll essentials of do_remount_sb() into devpts
  vfs: simple_set_mnt() should return void
  fs: move bdev code out of buffer.c
  constify dentry_operations: rest
  constify dentry_operations: configfs
  constify dentry_operations: sysfs
  constify dentry_operations: JFS
  constify dentry_operations: OCFS2
  constify dentry_operations: GFS2
  constify dentry_operations: FAT
  constify dentry_operations: FUSE
  constify dentry_operations: procfs
  constify dentry_operations: ecryptfs
  constify dentry_operations: CIFS
  constify dentry_operations: AFS
  ...
2009-03-27 16:23:12 -07:00
Sukadev Bhattiprolu
a3ec947c85 vfs: simple_set_mnt() should return void
simple_set_mnt() is defined as returning 'int' but always returns 0.
Callers assume simple_set_mnt() never fails and don't properly cleanup if
it were to _ever_ fail.  For instance, get_sb_single() and get_sb_nodev()
should:

        up_write(sb->s_unmount);
        deactivate_super(sb);

if simple_set_mnt() fails.

Since simple_set_mnt() never fails, would be cleaner if it did not
return anything.

[akpm@linux-foundation.org: fix build]
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-03-27 14:44:03 -04:00
Matthew Garrett
0a1c01c947 Make relatime default
Change the default behaviour of the kernel to use relatime for all
filesystems. This can be overridden with the "strictatime" mount
option.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-26 11:01:10 -07:00
Matthew Garrett
d0adde574b Add a strictatime mount option
Add support for explicitly requesting full atime updates. This makes it
possible for kernels to default to relatime but still allow userspace to
override it.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-26 10:56:35 -07:00
Al Viro
1a88b5364b Fix incomplete __mntput locking
Getting this wrong caused

	WARNING: at fs/namespace.c:636 mntput_no_expire+0xac/0xf2()

due to optimistically checking cpu_writer->mnt outside the spinlock.

Here's what we really want:
 * we know that nobody will set cpu_writer->mnt to mnt from now on
 * all changes to that sucker are done under cpu_writer->lock
 * we want the laziest equivalent of
	spin_lock(&cpu_writer->lock);
	if (likely(cpu_writer->mnt != mnt)) {
		spin_unlock(&cpu_writer->lock);
		continue;
	}
	/* do stuff */
  that would make sure we won't miss earlier setting of ->mnt done by
  another CPU.

Anyway, for now we just move the spin_lock() earlier and move the test
into the properly locked region.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Reported-and-tested-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-02-17 14:02:08 -08:00
Heiko Carstens
3480b25743 [CVE-2009-0029] System call wrappers part 14
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2009-01-14 14:15:24 +01:00
Heiko Carstens
bdc480e3be [CVE-2009-0029] System call wrappers part 10
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2009-01-14 14:15:22 +01:00
Julia Lawall
5cc4a0341a fs/namespace.c: drop code after return
The extra semicolon serves no purpose.

Signed-off-by: Julia Lawall <julia@diku.dk>
Reviewed-by: Richard Genoud <richard.genoud@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-12-31 18:07:38 -05:00
James Morris
2b82892565 Merge branch 'master' into next
Conflicts:
	security/keys/internal.h
	security/keys/process_keys.c
	security/keys/request_key.c

Fixed conflicts above by using the non 'tsk' versions.

Signed-off-by: James Morris <jmorris@namei.org>
2008-11-14 11:29:12 +11:00
David Howells
da9592edeb CRED: Wrap task credential accesses in the filesystem subsystem
Wrap access to task credentials so that they can be separated more easily from
the task_struct during the introduction of COW creds.

Change most current->(|e|s|fs)[ug]id to current_(|e|s|fs)[ug]id().

Change some task->e?[ug]id to task_e?[ug]id().  In some places it makes more
sense to use RCU directly rather than a convenient wrapper; these will be
addressed by later patches.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: James Morris <jmorris@namei.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: James Morris <jmorris@namei.org>
2008-11-14 10:39:05 +11:00
Eric W. Biederman
afef80b3d8 vfs: fix shrink_submounts
In the last refactoring of shrink_submounts a variable was not completely
renamed.  So finish the renaming of mnt to m now.

Without this if you attempt to mount an nfs mount that has both automatic
nfs sub mounts on it, and has normal mounts on it.  The unmount will
succeed when it should not.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-11-12 17:17:17 -08:00
Dan Williams
0e55a7cca4 [RFC PATCH] touch_mnt_namespace when the mount flags change
Daemons that need to be launched while the rootfs is read-only can now
poll /proc/mounts to be notified when their O_RDWR requests may no
longer end in EROFS.

Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2008-10-23 05:13:23 -04:00
Al Viro
0a0d8a4675 [PATCH] no need for noinline stuff in fs/namespace.c anymore
Stack footprint from hell had been due to many struct nameidata in there.
No more.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-10-23 03:34:22 -04:00
Al Viro
2d92ab3c62 [PATCH] finally get rid of nameidata in namespace.c
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-10-23 03:34:20 -04:00
Al Viro
8d66bf5481 [PATCH] pass struct path * to do_add_mount()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-08-01 11:25:32 -04:00
Al Viro
2d8f30380a [PATCH] sanitize __user_walk_fd() et.al.
* do not pass nameidata; struct path is all the callers want.
* switch to new helpers:
	user_path_at(dfd, pathname, flags, &path)
	user_path(pathname, &path)
	user_lpath(pathname, &path)
	user_path_dir(pathname, &path)  (fail if not a directory)
  The last 3 are trivial macro wrappers for the first one.
* remove nameidata in callers.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-07-26 20:53:34 -04:00
Li Zefan
88b387824f [PATCH] vfs: use kstrdup() and check failing allocation
- use kstrdup() instead of kmalloc() + memcpy()
- return NULL if allocating ->mnt_devname failed
- mnt_devname should be const

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Cyrill Gorcunov <gorcunov@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-07-26 20:53:24 -04:00
Al Viro
7f2da1e7d0 [PATCH] kill altroot
long overdue...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-07-26 20:53:20 -04:00
Arjan van de Ven
5c752ad9f3 Use WARN() in fs/
Use WARN() instead of a printk+WARN_ON() pair; this way the message
becomes part of the warning section for better reporting/collection.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-26 12:00:07 -07:00
Eric Paris
2069f45784 LSM/SELinux: show LSM mount options in /proc/mounts
This patch causes SELinux mount options to show up in /proc/mounts.  As
with other code in the area seq_put errors are ignored.  Other LSM's
will not have their mount options displayed until they fill in their own
security_sb_show_options() function.

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: James Morris <jmorris@namei.org>
2008-07-14 15:02:05 +10:00
Harvey Harrison
8e24eea728 fs: replace remaining __FUNCTION__ occurrences
__FUNCTION__ is gcc-specific, use __func__

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:54 -07:00
Jan Blunck
7ec02ef159 vfs: remove lives_below_in_same_fs()
Remove lives_below_in_same_fs() since is_subdir() from fs/dcache.c is
providing the same functionality.

Signed-off-by: Jan Blunck <jblunck@suse.de>
Acked-by: Miklos Szeredi <mszeredi@suse.cz>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:06 -07:00
Jan Kara
8794b5b246 quota: remove superfluous DQUOT_OFF() in fs/namespace.c
We don't need to turn quotas off before remounting root ro, because
do_remount_sb() already handles this.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28 08:58:33 -07:00
Al Viro
42faad9965 [PATCH] restore sane ->umount_begin() API
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-04-25 09:23:25 -04:00
Miklos Szeredi
97e7e0f71d [patch 7/7] vfs: mountinfo: show dominating group id
Show peer group ID of nearest dominating group that has intersection
with the mount's namespace.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-04-23 00:05:09 -04:00
Ram Pai
2d4d4864ac [patch 6/7] vfs: mountinfo: add /proc/<pid>/mountinfo
[mszeredi@suse.cz] rewrite and split big patch into managable chunks

/proc/mounts in its current form lacks important information:

 - propagation state
 - root of mount for bind mounts
 - the st_dev value used within the filesystem
 - identifier for each mount and it's parent

It also suffers from the following problems:

 - not easily extendable
 - ambiguity of mountpoints within a chrooted environment
 - doesn't distinguish between filesystem dependent and independent options
 - doesn't distinguish between per mount and per super block options

This patch introduces /proc/<pid>/mountinfo which attempts to address
all these deficiencies.

Code shared between /proc/<pid>/mounts and /proc/<pid>/mountinfo is
extracted into separate functions.

Thanks to Al Viro for the help in getting the design right.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-04-23 00:05:03 -04:00
Miklos Szeredi
a1a2c409b6 [patch 5/7] vfs: mountinfo: allow using process root
Allow /proc/<pid>/mountinfo to use the root of <pid> to calculate
mountpoints.

 - move definition of 'struct proc_mounts' to <linux/mnt_namespace.h>
 - add the process's namespace and root to this structure
 - pass a pointer to 'struct proc_mounts' into seq_operations

In addition the following cleanups are made:

 - use a common open function for /proc/<pid>/{mounts,mountstat}
 - surround namespace.c part of these proc files with #ifdef CONFIG_PROC_FS
 - make the seq_operations structures const

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-04-23 00:04:57 -04:00
Miklos Szeredi
719f5d7f0b [patch 4/7] vfs: mountinfo: add mount peer group ID
Add a unique ID to each peer group using the IDR infrastructure.  The
identifiers are reused after the peer group dissolves.

The IDR structures are protected by holding namepspace_sem for write
while allocating or deallocating IDs.

IDs are allocated when a previously unshared vfsmount becomes the
first member of a peer group.  When a new member is added to an
existing group, the ID is copied from one of the old members.

IDs are freed when the last member of a peer group is unshared.

Setting the MNT_SHARED flag on members of a subtree is done as a
separate step, after all the IDs have been allocated.  This way an
allocation failure can be cleaned up easilty, without affecting the
propagation state.

Based on design sketch by Al Viro.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-04-23 00:04:51 -04:00
Miklos Szeredi
73cd49ecdd [patch 3/7] vfs: mountinfo: add mount ID
Add a unique ID to each vfsmount using the IDR infrastructure.  The
identifiers are reused after the vfsmount is freed.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-04-23 00:04:45 -04:00
Al Viro
8c3ee42e80 [PATCH] get rid of more nameidata passing in namespace.c
Further reduction of stack footprint (sys_pivot_root());
lose useless BKL in there, while we are at it.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-04-21 23:13:47 -04:00
Al Viro
b5266eb4c8 [PATCH] switch a bunch of LSM hooks from nameidata to path
Namely, ones from namespace.c

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-04-21 23:13:23 -04:00
Al Viro
1a60a28077 [PATCH] lock exclusively in collect_mounts() and drop_collected_mounts()
Taking namespace_sem shared there isn't worth the trouble, especially with
vfsmount ID allocation about to be added.  That way we know that umount_tree(),
copy_tree() and clone_mnt() are _always_ serialized by namespace_sem.
umount_tree() still needs vfsmount_lock (it manipulates hash chains, among
other things), but that's a separate story.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-04-21 23:11:09 -04:00
Dave Hansen
2e4b7fcd92 [PATCH] r/o bind mounts: honor mount writer counts at remount
Originally from: Herbert Poetzl <herbert@13thfloor.at>

This is the core of the read-only bind mount patch set.

Note that this does _not_ add a "ro" option directly to the bind mount
operation.  If you require such a mount, you must first do the bind, then
follow it up with a 'mount -o remount,ro' operation:

If you wish to have a r/o bind mount of /foo on bar:

	mount --bind /foo /bar
	mount -o remount,ro /bar

Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-04-19 00:29:27 -04:00
Dave Hansen
3d733633a6 [PATCH] r/o bind mounts: track numbers of writers to mounts
This is the real meat of the entire series.  It actually
implements the tracking of the number of writers to a mount.
However, it causes scalability problems because there can be
hundreds of cpus doing open()/close() on files on the same mnt at
the same time.  Even an atomic_t in the mnt has massive scalaing
problems because the cacheline gets so terribly contended.

This uses a statically-allocated percpu variable.  All want/drop
operations are local to a cpu as long that cpu operates on the same
mount, and there are no writer count imbalances.  Writer count
imbalances happen when a write is taken on one cpu, and released
on another, like when an open/close pair is performed on two

Upon a remount,ro request, all of the data from the percpu
variables is collected (expensive, but very rare) and we determine
if there are any outstanding writers to the mount.

I've written a little benchmark to sit in a loop for a couple of
seconds in several cpus in parallel doing open/write/close loops.

http://sr71.net/~dave/linux/openbench.c

The code in here is a a worst-possible case for this patch.  It
does opens on a _pair_ of files in two different mounts in parallel.
This should cause my code to lose its "operate on the same mount"
optimization completely.  This worst-case scenario causes a 3%
degredation in the benchmark.

I could probably get rid of even this 3%, but it would be more
complex than what I have here, and I think this is getting into
acceptable territory.  In practice, I expect writing more than 3
bytes to a file, as well as disk I/O to mask any effects that this
has.

(To get rid of that 3%, we could have an #defined number of mounts
in the percpu variable.  So, instead of a CPU getting operate only
on percpu data when it accesses only one mount, it could stay on
percpu data when it only accesses N or fewer mounts.)

[AV] merged fix for __clear_mnt_mount() stepping on freed vfsmount

Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-04-19 00:29:27 -04:00
Dave Hansen
8366025eb8 [PATCH] r/o bind mounts: stub functions
This patch adds two function mnt_want_write() and mnt_drop_write().  These are
used like a lock pair around and fs operations that might cause a write to the
filesystem.

Before these can become useful, we must first cover each place in the VFS
where writes are performed with a want/drop pair.  When that is complete, we
can actually introduce code that will safely check the counts before allowing
r/w<->r/o transitions to occur.

Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-04-19 00:25:32 -04:00
Al Viro
6758f953d0 [PATCH] mnt_expire is protected by namespace_sem, no need for vfsmount_lock
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-03-27 20:48:04 -04:00
Al Viro
c35038beca [PATCH] do shrink_submounts() for all fs types
... and take it out of ->umount_begin() instances.  Call with all locks
already taken (by do_umount()) and leave calling release_mounts() to
caller (it will do release_mounts() anyway, so we can just put into
the same list).

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-03-27 20:47:58 -04:00
Al Viro
bcc5c7d2b6 [PATCH] sanitize locking in mark_mounts_for_expiry() and shrink_submounts()
... and fix a race on access of ->mnt_share et.al. without namespace_sem
in the latter.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-03-27 20:47:52 -04:00
Al Viro
7c4b93d826 [PATCH] count ghost references to vfsmounts
make propagate_mount_busy() exclude references from the vfsmounts
that had been isolated by umount_tree() and are just waiting for
release_mounts() to dispose of their ->mnt_parent/->mnt_mountpoint.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-03-27 20:47:46 -04:00
Al Viro
1a39068954 [PATCH] reduce stack footprint in namespace.c
A lot of places misuse struct nameidata when they need struct path.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-03-27 20:47:40 -04:00
Jan Blunck
c32c2f63a9 d_path: Make seq_path() use a struct path argument
seq_path() is always called with a dentry and a vfsmount from a struct path.
Make seq_path() take it directly as an argument.

Signed-off-by: Jan Blunck <jblunck@suse.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-14 21:17:08 -08:00
Jan Blunck
ac748a09fc Make set_fs_{root,pwd} take a struct path
In nearly all cases the set_fs_{root,pwd}() calls work on a struct
path. Change the function to reflect this and use path_get() here.

Signed-off-by: Jan Blunck <jblunck@suse.de>
Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-14 21:13:33 -08:00
Jan Blunck
6ac08c39a1 Use struct path in fs_struct
* Use struct path in fs_struct.

Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Signed-off-by: Jan Blunck <jblunck@suse.de>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-14 21:13:33 -08:00
Jan Blunck
1d957f9bf8 Introduce path_put()
* Add path_put() functions for releasing a reference to the dentry and
  vfsmount of a struct path in the right order

* Switch from path_release(nd) to path_put(&nd->path)

* Rename dput_path() to path_put_conditional()

[akpm@linux-foundation.org: fix cifs]
Signed-off-by: Jan Blunck <jblunck@suse.de>
Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Acked-by: Christoph Hellwig <hch@lst.de>
Cc: <linux-fsdevel@vger.kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Steven French <sfrench@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-14 21:13:33 -08:00
Jan Blunck
4ac9137858 Embed a struct path into struct nameidata instead of nd->{dentry,mnt}
This is the central patch of a cleanup series. In most cases there is no good
reason why someone would want to use a dentry for itself. This series reflects
that fact and embeds a struct path into nameidata.

Together with the other patches of this series
- it enforced the correct order of getting/releasing the reference count on
  <dentry,vfsmount> pairs
- it prepares the VFS for stacking support since it is essential to have a
  struct path in every place where the stack can be traversed
- it reduces the overall code size:

without patch series:
   text    data     bss     dec     hex filename
5321639  858418  715768 6895825  6938d1 vmlinux

with patch series:
   text    data     bss     dec     hex filename
5320026  858418  715768 6894212  693284 vmlinux

This patch:

Switch from nd->{dentry,mnt} to nd->path.{dentry,mnt} everywhere.

[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: fix cifs]
[akpm@linux-foundation.org: fix smack]
Signed-off-by: Jan Blunck <jblunck@suse.de>
Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Acked-by: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-14 21:13:33 -08:00
Jan Blunck
429731b155 Remove path_release_on_umount()
path_release_on_umount() should only be called from sys_umount(). I merged the
function into sys_umount() instead of having in in namei.c.

Signed-off-by: Jan Blunck <jblunck@suse.de>
Acked-by: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-14 21:13:32 -08:00
Eric Sandeen
2dafe1c4d6 reduce large do_mount stack usage with noinlines
do_mount() uses a whopping 616 bytes of stack on x86_64 in 2.6.24-mm1,
largely thanks to gcc inlining the various helper functions.

noinlining these can slim it down a lot; on my box this patch gets it down
to 168, which is mostly the struct nameidata nd; left on the stack.

These functions are called only as do_mount() helpers; none of them should
be in any path that would see a performance benefit from inlining...

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Cc: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08 09:22:44 -08:00
Miklos Szeredi
b3b304a23a mount options: add generic_show_options()
Add a new s_options field to struct super_block.  Filesystems can save
mount options passed to them in mount or remount.  It is automatically
freed when the superblock is destroyed.

A new helper function, generic_show_options() is introduced, which uses
this field to display the mount options in /proc/mounts.

Another helper function, save_mount_options() may be used by
filesystems to save the options in the super block.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08 09:22:39 -08:00
Eric Dumazet
13f14b4d8b Use ilog2() in fs/namespace.c
We can use ilog2() in fs/namespace.c to compute hash_bits and hash_mask at
compile time, not runtime.

[akpm@linux-foundation.org: clean it all up]
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-06 10:41:09 -08:00
Greg Kroah-Hartman
00d2666623 kobject: convert main fs kobject to use kobject_create
This also renames fs_subsys to fs_kobj to catch all current users with a
build error instead of a build warning which can easily be missed.


Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-01-24 20:40:13 -08:00
Greg Kroah-Hartman
3514faca19 kobject: remove struct kobj_type from struct kset
We don't need a "default" ktype for a kset.  We should set this
explicitly every time for each kset.  This change is needed so that we
can make ksets dynamic, and cleans up one of the odd, undocumented
assumption that the kset/kobject/ktype model has.

This patch is based on a lot of help from Kay Sievers.

Nasty bug in the block code was found by Dave Young
<hidave.darkstar@gmail.com>

Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Dave Young <hidave.darkstar@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-01-24 20:40:10 -08:00
Al Viro
8aec080945 [PATCH] new helpers - collect_mounts() and release_collected_mounts()
Get a snapshot of a subtree, creating private clones of vfsmounts
for all its components and release such snapshot resp.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2007-10-21 02:37:25 -04:00
Pavel Emelyanov
8bf9725c29 pid namespaces: introduce MS_KERNMOUNT flag
This flag tells the .get_sb callback that this is a kern_mount() call so that
it can trust *data pointer to be valid in-kernel one.  If this flag is passed
from the user process, it is cleared since the *data pointer is not a valid
kernel object.

Running a few steps forward - this will be needed for proc to create the
superblock and store a valid pid namespace on it during the namespace
creation.  The reason, why the namespace cannot live without proc mount is
described in the appropriate patch.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Cc: Paul Menage <menage@google.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-19 11:53:38 -07:00
Denis Cheng
74bf17cffc fs: remove the unused mempages parameter
Since the mempages parameter is actually not used, they should be removed.

Now there is only files_init use the mempages parameter,

 	files_init(mempages);

but I don't think the adaptation to mempages in files_init is really
useful; and if files_init also changed to the prototype void (*func)(void),
the wrapper vfs_caches_init would also not need the mempages parameter.

Signed-off-by: Denis Cheng <crquan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-17 08:42:49 -07:00
Paul Mundt
20c2df83d2 mm: Remove slab destructors from kmem_cache_create().
Slab destructors were no longer supported after Christoph's
c59def9f22 change. They've been
BUGs for both slab and slub, and slob never supported them
either.

This rips out support for the dtor pointer from kmem_cache_create()
completely and fixes up every single callsite in the kernel (there were
about 224, not including the slab allocator definitions themselves,
or the documentation references).

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2007-07-20 10:11:58 +09:00
Adrian Bunk
948730b0e3 fs/namespace.c should #include "internal.h"
Every file should include the headers containing the prototypes for
its global functions.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16 09:05:50 -07:00
Eric W. Biederman
213dd266d4 namespace: ensure clone_flags are always stored in an unsigned long
While working on unshare support for the network namespace I noticed we
were putting clone flags in an int.  Which is weird because the syscall
uses unsigned long and we at least need an unsigned to properly hold all of
the unshare flags.

So to make the code consistent, this patch updates the code to use
unsigned long instead of int for the clone flags in those places
where we get it wrong today.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Cedric Le Goater <clg@fr.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16 09:05:48 -07:00
Cedric Le Goater
467e9f4b50 fix create_new_namespaces() return value
dup_mnt_ns() and clone_uts_ns() return NULL on failure.  This is wrong,
create_new_namespaces() uses ERR_PTR() to catch an error.  This means that the
subsequent create_new_namespaces() will hit BUG_ON() in copy_mnt_ns() or
copy_utsname().

Modify create_new_namespaces() to also use the errors returned by the
copy_*_ns routines and not to systematically return ENOMEM.

[oleg@tv-sign.ru: better changelog]
Signed-off-by: Cedric Le Goater <clg@fr.ibm.com>
Cc: Serge E. Hallyn <serue@us.ibm.com>
Cc: Badari Pulavarty <pbadari@us.ibm.com>
Cc: Pavel Emelianov <xemul@openvz.org>
Cc: Herbert Poetzl <herbert@13thfloor.at>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16 09:05:47 -07:00
Pavel Emelianov
b0765fb857 Make /proc/self/mounts(tats) use seq_list_xxx helpers
One more simple and stupid switching to the new API.

Signed-off-by: Pavel Emelianov <xemul@openvz.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16 09:05:42 -07:00
Miklos Szeredi
ee6f958291 check privileges before setting mount propagation
There's a missing check for CAP_SYS_ADMIN in do_change_type().

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-08 11:15:12 -07:00
Pavel Emelianov
b5e618181a Introduce a handy list_first_entry macro
There are many places in the kernel where the construction like

   foo = list_entry(head->next, struct foo_struct, list);

are used.
The code might look more descriptive and neat if using the macro

   list_first_entry(head, type, member) \
             list_entry((head)->next, type, member)

Here is the macro itself and the examples of its usage in the generic code.
 If it will turn out to be useful, I can prepare the set of patches to
inject in into arch-specific code, drivers, networking, etc.

Signed-off-by: Pavel Emelianov <xemul@openvz.org>
Signed-off-by: Kirill Korotaev <dev@openvz.org>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Zach Brown <zach.brown@oracle.com>
Cc: Davide Libenzi <davidel@xmailserver.org>
Cc: John McCutchan <ttb@tentacle.dhs.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-08 11:15:11 -07:00
Miklos Szeredi
79c0b2df79 add filesystem subtype support
There's a slight problem with filesystem type representation in fuse
based filesystems.

From the kernel's view, there are just two filesystem types: fuse and
fuseblk.  From the user's view there are lots of different filesystem
types.  The user is not even much concerned if the filesystem is fuse based
or not.  So there's a conflict of interest in how this should be
represented in fstab, mtab and /proc/mounts.

The current scheme is to encode the real filesystem type in the mount
source.  So an sshfs mount looks like this:

  sshfs#user@server:/   /mnt/server    fuse   rw,nosuid,nodev,...

This url-ish syntax works OK for sshfs and similar filesystems.  However
for block device based filesystems (ntfs-3g, zfs) it doesn't work, since
the kernel expects the mount source to be a real device name.

A possibly better scheme would be to encode the real type in the type
field as "type.subtype".  So fuse mounts would look like this:

  /dev/hda1       /mnt/windows   fuseblk.ntfs-3g   rw,...
  user@server:/   /mnt/server    fuse.sshfs        rw,nosuid,nodev,...

This patch adds the necessary code to the kernel so that this can be
correctly displayed in /proc/mounts.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-08 11:15:01 -07:00
Badari Pulavarty
e3222c4ecc Merge sys_clone()/sys_unshare() nsproxy and namespace handling
sys_clone() and sys_unshare() both makes copies of nsproxy and its associated
namespaces.  But they have different code paths.

This patch merges all the nsproxy and its associated namespace copy/clone
handling (as much as possible).  Posted on container list earlier for
feedback.

- Create a new nsproxy and its associated namespaces and pass it back to
  caller to attach it to right process.

- Changed all copy_*_ns() routines to return a new copy of namespace
  instead of attaching it to task->nsproxy.

- Moved the CAP_SYS_ADMIN checks out of copy_*_ns() routines.

- Removed unnessary !ns checks from copy_*_ns() and added BUG_ON()
  just incase.

- Get rid of all individual unshare_*_ns() routines and make use of
  copy_*_ns() instead.

[akpm@osdl.org: cleanups, warning fix]
[clg@fr.ibm.com: remove dup_namespaces() declaration]
[serue@us.ibm.com: fix CONFIG_IPC_NS=n, clone(CLONE_NEWIPC) retval]
[akpm@linux-foundation.org: fix build with CONFIG_SYSVIPC=n]
Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: Serge Hallyn <serue@us.ibm.com>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: <containers@lists.osdl.org>
Signed-off-by: Cedric Le Goater <clg@fr.ibm.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-08 11:15:00 -07:00
Robert P. J. Day
c376222960 [PATCH] Transform kmem_cache_alloc()+memset(0) -> kmem_cache_zalloc().
Replace appropriate pairs of "kmem_cache_alloc()" + "memset(0)" with the
corresponding "kmem_cache_zalloc()" call.

Signed-off-by: Robert P. J. Day <rpjday@mindspring.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Andi Kleen <ak@muc.de>
Cc: Roland McGrath <roland@redhat.com>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Cc: Greg KH <greg@kroah.com>
Acked-by: Joel Becker <Joel.Becker@oracle.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Jan Kara <jack@ucw.cz>
Cc: Michael Halcrow <mhalcrow@us.ibm.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: James Morris <jmorris@namei.org>
Cc: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11 10:51:27 -08:00
Valerie Henson
47ae32d6a5 [PATCH] relative atime
Add "relatime" (relative atime) support.  Relative atime only updates the
atime if the previous atime is older than the mtime or ctime.  Like
noatime, but useful for applications like mutt that need to know when a
file has been read since it was last modified.

A corresponding patch against mount(8) is available at
http://userweb.kernel.org/~akpm/mount-relative-atime.txt

Signed-off-by: Valerie Henson <val_henson@linux.intel.com>
Cc: Mark Fasheh <mark.fasheh@oracle.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Karel Zak <kzak@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-13 09:05:50 -08:00
Kirill Korotaev
6b3286ed11 [PATCH] rename struct namespace to struct mnt_namespace
Rename 'struct namespace' to 'struct mnt_namespace' to avoid confusion with
other namespaces being developped for the containers : pid, uts, ipc, etc.
'namespace' variables and attributes are also renamed to 'mnt_ns'

Signed-off-by: Kirill Korotaev <dev@sw.ru>
Signed-off-by: Cedric Le Goater <clg@fr.ibm.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Herbert Poetzl <herbert@13thfloor.at>
Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-08 08:28:51 -08:00