linux.git/fs/namespace.c, branch v2.6.14

[PATCH] janitor: fs/namespace.c: list_for_each_entry

2005-09-10T17:06:32+00:00

Make code more readable with list_for_each_entry.

Signed-off-by: Maximilian Attems 
Signed-off-by: Domen Puncer 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] pivot_root() circular reference fix

2005-09-07T23:58:01+00:00

Fix http://bugzilla.kernel.org/show_bug.cgi?id=4857

When pivot_root is called from an init script in an initramfs environment,
it causes a circular reference in the mount tree.

The cause of this is that pivot_root() is not prepared to handle pivoting
an unattached mount.  In an initramfs environment, rootfs is the root of
the namespace, and so it is not attached.

This patch fixes this and related problems, by returning -EINVAL if either
the current root or the new root is detached.

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

[PATCH] Additions to .data.read_mostly section

2005-09-07T23:57:33+00:00

Mark variables which are usually accessed for reads with __readmostly.

Signed-off-by: Alok N Kataria 
Signed-off-by: Shai Fultheim 
Signed-off-by: Ravikiran Thirumalai 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] namespace.c: fix bind mount from foreign namespace

2005-08-07T17:00:38+00:00

I'm resending this patch, because I still believe it's the correct fix.

Tested before/after applying the patch with a test application
available from:

  http://www.inf.bme.hu/~mszeredi/nstest.c

Bind mount from a foreign namespace results in an un-removable mount.
The reason is that mnt->mnt_namespace is copied from the old mount in
clone_mnt().  Because of this check_mnt() in sys_umount() will fail.

The solution is to set mnt->mnt_namespace to current->namespace in
clone_mnt().  clone_mnt() is either called from do_loopback() or
copy_tree().  copy_tree() is called from do_loopback() or
copy_namespace().

When called (directly or indirectly) from do_loopback(), always
current->namspace is being modified: check_mnt(nd->mnt).  So setting
mnt->mnt_namespace to current->namspace is the right thing to do.

When called from copy_namespace(), the setting of mnt_namespace is
irrelevant, since mnt_namespace is reset later in that function for
all copied mounts.

Jamie said:

  This patch is correct.  The old code was buggy for more fundamental and
  serious reason: it broke the invariant that a tree of vfsmnts all have the
  same value of mnt_namespace (and the same for the mnt_list list).

Signed-off-by: Miklos Szeredi 
Acked-by: Jamie Lokier 
Cc: 
Cc: Christoph Hellwig 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] namespace: rename mnt_fslink to mnt_expire

2005-07-08T01:23:52+00:00

This patch renames vfsmount->mnt_fslink to something a little more
descriptive: vfsmount->mnt_expire.

Signed-off-by: Mike Waychison 
Signed-off-by: Miklos Szeredi 
Acked-by: Christoph Hellwig 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] set mnt_namespace in the correct place

2005-07-08T01:23:52+00:00

This patch sets ->mnt_namespace where it's actually added to the
namespace.

Previously mnt_namespace was set in do_kern_mount() even if the filesystem
was never added to any process's namespace (most kernel-internal
filesystems).

This discrepancy doesn't actually cause any problems, but it's cleaner if
mnt_namespace is NULL for these non exported filesystems.

Signed-off-by: Miklos Szeredi 
Acked-by: Christoph Hellwig 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] namespace.c: fix mnt_namespace zeroing for expired mounts

2005-07-08T01:23:51+00:00

This patch clears mnt_namespace in an expired mount.

If mnt_namespace is not cleared, it's possible to attach a new mount to the
already detached mount, because check_mnt() can return true.

The effect is a resource leak, since the resulting tree will never be
freed.

Signed-off-by: Miklos Szeredi 
Acked-by: Christoph Hellwig 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] namespace.c: fix expiring of detached mount

2005-07-08T01:23:51+00:00

This patch fixes a bug noticed by Al Viro:

   However, we still have a problem here - just what would
   happen if vfsmount is detached while we were grabbing namespace
   semaphore?  Refcount alone is not useful here - we might be held by
   whoever had detached the vfsmount.  IOW, we should check that it's
   still attached (i.e. that mnt->mnt_parent != mnt).  If it's not -
   just leave it alone, do mntput() and let whoever holds it deal with
   the sucker.  No need to put it back on lists.

Signed-off-by: Miklos Szeredi 
Cc: 
Acked-by: Christoph Hellwig 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] namespace.c: split mark_mounts_for_expiry()

2005-07-08T01:23:51+00:00

This patch splits the mark_mounts_for_expiry() function.  It's too complex and
too deeply nested, even without the bugfix in the following patch.

Otherwise code is completely the same.

Signed-off-by: Miklos Szeredi 
Cc: 
Acked-by: Christoph Hellwig 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] namespace.c: cleanup in mark_mounts_for_expiry()

2005-07-08T01:23:51+00:00

This patch simplifies mark_mounts_for_expiry() by using detach_mnt() instead
of duplicating everything it does.

It should be an equivalent transformation except for righting the dput/mntput
order.

Al Viro said: "Looks sane".

Signed-off-by: Miklos Szeredi 
Cc: 
Acked-by: Christoph Hellwig 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds