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>

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>

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>

Since commit 0a1c01c9477602ee8b44548a9405b2c1d587b5a2 ("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>

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>

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>

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>

* '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
  ...

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>

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>