Move actual pte filling for non-linear file mappings into the new special
vma operation: ->remap_pages().

Filesystems must implement this method to get non-linear mapping support,
if it uses filemap_fault() then generic_file_remap_pages() can be used.

Now device drivers can implement this method and obtain nonlinear vma support.

Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Carsten Otte <cotte@de.ibm.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>	#arch/tile
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Eric Paris <eparis@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Morris <james.l.morris@oracle.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Kentaro Takeda <takedakn@nttdata.co.jp>
Cc: Matt Helsley <matthltc@us.ibm.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Venkatesh Pallipadi <venki@google.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

There's no reason to call rcu_barrier() on every
deactivate_locked_super().  We only need to make sure that all delayed rcu
free inodes are flushed before we destroy related cache.

Removing rcu_barrier() from deactivate_locked_super() affects some fast
paths.  E.g.  on my machine exit_group() of a last process in IPC
namespace takes 0.07538s.  rcu_barrier() takes 0.05188s of that time.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

simplifies a bunch of callers...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

In some cases fuse_retrieve() would return a short byte count if offset was
non-zero.  The data returned was correct, though.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Cc: stable@vger.kernel.org

gcc 4.6.3 complains about uninitialized variables in fs/fuse/control.c:

  CC      fs/fuse/control.o
fs/fuse/control.c: In function 'fuse_conn_congestion_threshold_write':
fs/fuse/control.c:165:29: warning: 'val' may be used uninitialized in this function [-Wuninitialized]
fs/fuse/control.c: In function 'fuse_conn_max_background_write':
fs/fuse/control.c:128:23: warning: 'val' may be used uninitialized in this function [-Wuninitialized]

fuse_conn_limit_write() will always return non-zero unless the &val
is modified, so the warning is misleading. Let the compiler know
about it by marking 'val' with 'uninitialized_var'.

Signed-off-by: Daniel Mack <zonque@gmail.com>
Cc: Brian Foster <bfoster@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>

Luca Risolia reported that a CUSE daemon will continue to run even if
initialization of the emulated device failes for some reason (e.g. the device
number is already registered by another driver).

This patch disconnects the fuse device on error, which will make the userspace
CUSE daemon exit, albeit without indication about what the problem was.

Reported-by: Luca Risolia <luca.risolia@studio.unibo.it>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>

fuse_conn_kill() removed fc->entry, called fuse_ctl_remove_conn() and
fuse_bdi_destroy().  None of which is appropriate for cuse cleanup.

The fuse_ctl_remove_conn() decrements the nlink on the control filesystem, which
is totally bogus.  The others are harmless but unnecessary.

So move these out from fuse_conn_kill() to fuse_put_super() where they belong.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>

Pull vfs fixes from Miklos Szeredi.

This mainly fixes some confusion about whether the open 'mode' variable
passed around should contain the full file type (S_IFREG etc)
information or just the permission mode.  In particular, the lack of
proper file type information had confused fuse.

* 'vfs-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs:
  vfs: fix propagation of atomic_open create error on negative dentry
  fuse: check create mode in atomic open
  vfs: pass right create mode to may_o_create()
  vfs: atomic_open(): fix create mode usage
  vfs: canonicalize create mode in build_open_flags()

Pull fuse updates from Miklos Szeredi.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
  fuse: verify all ioctl retry iov elements
  fuse: add missing INIT flag descriptions
  fuse: add missing INIT flags
  fuse: update attributes on aio_read
  fuse: invalidate inode mapping if mtime changes
  fuse: add FUSE_AUTO_INVAL_DATA init flag

Verify that the VFS is passing us a complete create mode with the S_IFREG to
atomic open.

Reported-by: Steve <steveamigauk@yahoo.co.uk>
Reported-by: Richard W.M. Jones <rjones@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Tested-by: Richard W.M. Jones <rjones@redhat.com>