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Linus Torvalds ed2d265d12 The following text was taken from the original review request:
"[RFC - PATCH 0/7] consolidation of BUG support code."
 		https://lkml.org/lkml/2012/1/26/525
 --
 
 The changes shown here are to unify linux's BUG support under
 the one <linux/bug.h> file.  Due to historical reasons, we have
 some BUG code in bug.h and some in kernel.h -- i.e. the support for
 BUILD_BUG in linux/kernel.h predates the addition of linux/bug.h,
 but old code in kernel.h wasn't moved to bug.h at that time.  As
 a band-aid, kernel.h was including <asm/bug.h> to pseudo link them.
 
 This has caused confusion[1] and general yuck/WTF[2] reactions.
 Here is an example that violates the principle of least surprise:
 
       CC      lib/string.o
       lib/string.c: In function 'strlcat':
       lib/string.c:225:2: error: implicit declaration of function 'BUILD_BUG_ON'
       make[2]: *** [lib/string.o] Error 1
       $
       $ grep linux/bug.h lib/string.c
       #include <linux/bug.h>
       $
 
 We've included <linux/bug.h> for the BUG infrastructure and yet we
 still get a compile fail!  [We've not kernel.h for BUILD_BUG_ON.]
 Ugh - very confusing for someone who is new to kernel development.
 
 With the above in mind, the goals of this changeset are:
 
 1) find and fix any include/*.h files that were relying on the
    implicit presence of BUG code.
 2) find and fix any C files that were consuming kernel.h and
    hence relying on implicitly getting some/all BUG code.
 3) Move the BUG related code living in kernel.h to <linux/bug.h>
 4) remove the asm/bug.h from kernel.h to finally break the chain.
 
 During development, the order was more like 3-4, build-test, 1-2.
 But to ensure that git history for bisect doesn't get needless
 build failures introduced, the commits have been reorderd to fix
 the problem areas in advance.
 
 [1]  https://lkml.org/lkml/2012/1/3/90
 [2]  https://lkml.org/lkml/2012/1/17/414
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Merge tag 'bug-for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux

Pull <linux/bug.h> cleanup from Paul Gortmaker:
 "The changes shown here are to unify linux's BUG support under the one
  <linux/bug.h> file.  Due to historical reasons, we have some BUG code
  in bug.h and some in kernel.h -- i.e.  the support for BUILD_BUG in
  linux/kernel.h predates the addition of linux/bug.h, but old code in
  kernel.h wasn't moved to bug.h at that time.  As a band-aid, kernel.h
  was including <asm/bug.h> to pseudo link them.

  This has caused confusion[1] and general yuck/WTF[2] reactions.  Here
  is an example that violates the principle of least surprise:

      CC      lib/string.o
      lib/string.c: In function 'strlcat':
      lib/string.c:225:2: error: implicit declaration of function 'BUILD_BUG_ON'
      make[2]: *** [lib/string.o] Error 1
      $
      $ grep linux/bug.h lib/string.c
      #include <linux/bug.h>
      $

  We've included <linux/bug.h> for the BUG infrastructure and yet we
  still get a compile fail! [We've not kernel.h for BUILD_BUG_ON.] Ugh -
  very confusing for someone who is new to kernel development.

  With the above in mind, the goals of this changeset are:

  1) find and fix any include/*.h files that were relying on the
     implicit presence of BUG code.
  2) find and fix any C files that were consuming kernel.h and hence
     relying on implicitly getting some/all BUG code.
  3) Move the BUG related code living in kernel.h to <linux/bug.h>
  4) remove the asm/bug.h from kernel.h to finally break the chain.

  During development, the order was more like 3-4, build-test, 1-2.  But
  to ensure that git history for bisect doesn't get needless build
  failures introduced, the commits have been reorderd to fix the problem
  areas in advance.

	[1]  https://lkml.org/lkml/2012/1/3/90
	[2]  https://lkml.org/lkml/2012/1/17/414"

Fix up conflicts (new radeon file, reiserfs header cleanups) as per Paul
and linux-next.

* tag 'bug-for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux:
  kernel.h: doesn't explicitly use bug.h, so don't include it.
  bug: consolidate BUILD_BUG_ON with other bug code
  BUG: headers with BUG/BUG_ON etc. need linux/bug.h
  bug.h: add include of it to various implicit C users
  lib: fix implicit users of kernel.h for TAINT_WARN
  spinlock: macroize assert_spin_locked to avoid bug.h dependency
  x86: relocate get/set debugreg fcns to include/asm/debugreg.
2012-03-24 10:08:39 -07:00
Linus Torvalds f1d38e423a Merge git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/sysctl
Pull sysctl updates from Eric Biederman:

 - Rewrite of sysctl for speed and clarity.

   Insert/remove/Lookup in sysctl are all now O(NlogN) operations, and
   are no longer bottlenecks in the process of adding and removing
   network devices.

   sysctl is now focused on being a filesystem instead of system call
   and the code can all be found in fs/proc/proc_sysctl.c.  Hopefully
   this means the code is now approachable.

   Much thanks is owed to Lucian Grinjincu for keeping at this until
   something was found that was usable.

 - The recent proc_sys_poll oops found by the fuzzer during hibernation
   is fixed.

* git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/sysctl: (36 commits)
  sysctl: protect poll() in entries that may go away
  sysctl: Don't call sysctl_follow_link unless we are a link.
  sysctl: Comments to make the code clearer.
  sysctl: Correct error return from get_subdir
  sysctl: An easier to read version of find_subdir
  sysctl: fix memset parameters in setup_sysctl_set()
  sysctl: remove an unused variable
  sysctl: Add register_sysctl for normal sysctl users
  sysctl: Index sysctl directories with rbtrees.
  sysctl: Make the header lists per directory.
  sysctl: Move sysctl_check_dups into insert_header
  sysctl: Modify __register_sysctl_paths to take a set instead of a root and an nsproxy
  sysctl: Replace root_list with links between sysctl_table_sets.
  sysctl: Add sysctl_print_dir and use it in get_subdir
  sysctl: Stop requiring explicit management of sysctl directories
  sysctl: Add a root pointer to ctl_table_set
  sysctl: Rewrite proc_sys_readdir in terms of first_entry and next_entry
  sysctl: Rewrite proc_sys_lookup introducing find_entry and lookup_entry.
  sysctl: Normalize the root_table data structure.
  sysctl: Factor out insert_header and erase_header
  ...
2012-03-23 18:08:58 -07:00
KAMEZAWA Hiroyuki e075f59152 seq_file: add seq_set_overflow(), seq_overflow()
It is undocumented but a seq_file's overflow state is indicated by
m->count == m->size.  Add seq_set_overflow() and seq_overflow() to
set/check overflow status explicitly.

Based on an idea from Eric Dumazet.

[akpm@linux-foundation.org: tweak code comment]
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Eric Dumazet <eric.dumazet@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>
2012-03-23 16:58:42 -07:00
Pravin B Shelar 1b26c9b334 proc-ns: use d_set_d_op() API to set dentry ops in proc_ns_instantiate().
The namespace cleanup path leaks a dentry which holds a reference count
on a network namespace.  Keeping that network namespace from being freed
when the last user goes away.  Leaving things like vlan devices in the
leaked network namespace.

If you use ip netns add for much real work this problem becomes apparent
pretty quickly.  It light testing the problem hides because frequently
you simply don't notice the leak.

Use d_set_d_op() so that DCACHE_OP_* flags are set correctly.

This issue exists back to 3.0.

Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Reported-by: Justin Pettit <jpettit@nicira.com>
Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: Jesse Gross <jesse@nicira.com>
Cc: David Miller <davem@davemloft.net>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23 16:58:42 -07:00
KAMEZAWA Hiroyuki bda7bad62b procfs: speed up /proc/pid/stat, statm
Process accounting applications as top, ps visit some files under
/proc/<pid>.  With seq_put_decimal_ull(), we can optimize /proc/<pid>/stat
and /proc/<pid>/statm files.

This patch adds
  - seq_put_decimal_ll() for signed values.
  - allow delimiter == 0.
  - convert seq_printf() to seq_put_decimal_ull/ll in /proc/stat, statm.

Test result on a system with 2000+ procs.

Before patch:
  [kamezawa@bluextal test]$ top -b -n 1 | wc -l
  2223
  [kamezawa@bluextal test]$ time top -b -n 1 > /dev/null

  real    0m0.675s
  user    0m0.044s
  sys     0m0.121s

  [kamezawa@bluextal test]$ time ps -elf > /dev/null

  real    0m0.236s
  user    0m0.056s
  sys     0m0.176s

After patch:
  kamezawa@bluextal ~]$ time top -b -n 1 > /dev/null

  real    0m0.657s
  user    0m0.052s
  sys     0m0.100s

  [kamezawa@bluextal ~]$ time ps -elf > /dev/null

  real    0m0.198s
  user    0m0.050s
  sys     0m0.145s

Considering top, ps tend to scan /proc periodically, this will reduce cpu
consumption by top/ps to some extent.

[akpm@linux-foundation.org: checkpatch fixes]
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23 16:58:42 -07:00
KAMEZAWA Hiroyuki 1ac101a5d6 procfs: add num_to_str() to speed up /proc/stat
== stat_check.py
num = 0
with open("/proc/stat") as f:
        while num < 1000 :
                data = f.read()
                f.seek(0, 0)
                num = num + 1
==

perf shows

    20.39%  stat_check.py  [kernel.kallsyms]    [k] format_decode
    13.41%  stat_check.py  [kernel.kallsyms]    [k] number
    12.61%  stat_check.py  [kernel.kallsyms]    [k] vsnprintf
    10.85%  stat_check.py  [kernel.kallsyms]    [k] memcpy
     4.85%  stat_check.py  [kernel.kallsyms]    [k] radix_tree_lookup
     4.43%  stat_check.py  [kernel.kallsyms]    [k] seq_printf

This patch removes most of calls to vsnprintf() by adding num_to_str()
and seq_print_decimal_ull(), which prints decimal numbers without rich
functions provided by printf().

On my 8cpu box.
== Before patch ==
[root@bluextal test]# time ./stat_check.py

real    0m0.150s
user    0m0.026s
sys     0m0.121s

== After patch ==
[root@bluextal test]# time ./stat_check.py

real    0m0.055s
user    0m0.022s
sys     0m0.030s

[akpm@linux-foundation.org: remove incorrect comment, use less statck in num_to_str(), move comment from .h to .c, simplify seq_put_decimal_ull()]
[andrea@betterlinux.com: avoid breaking the ABI in /proc/stat]
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrea Righi <andrea@betterlinux.com>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Glauber Costa <glommer@parallels.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Turner <pjt@google.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23 16:58:42 -07:00
Eric Dumazet 59a32e2ce5 proc: speed up /proc/stat handling
On a typical 16 cpus machine, "cat /proc/stat" gives more than 4096 bytes,
and is slow :

  # strace -T -o /tmp/STRACE cat /proc/stat | wc -c
  5826
  # grep "cpu " /tmp/STRACE
  read(0, "cpu  1949310 19 2144714 12117253"..., 32768) = 5826 <0.001504>

Thats partly because show_stat() must be called twice since initial
buffer size is too small (4096 bytes for less than 32 possible cpus)

Fix this by :

 1) Taking into account nr_irqs in the initial buffer sizing.

 2) Using ksize() to allow better filling of initial buffer.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Glauber Costa <glommer@parallels.com>
Cc: Russell King - ARM Linux <linux@arm.linux.org.uk>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Paul Turner <pjt@google.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23 16:58:42 -07:00
Djalal Harouni b908243c54 fs/proc/kcore.c: make get_sparsemem_vmemmap_info() static
get_sparsemem_vmemmap_info() is only used inside fs/proc/kcore.c

Signed-off-by: Djalal Harouni <tixxdz@opendz.org>
Reviewed-by: WANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23 16:58:42 -07:00
Jason Baron accb61fe7b coredump: add VM_NODUMP, MADV_NODUMP, MADV_CLEAR_NODUMP
Since we no longer need the VM_ALWAYSDUMP flag, let's use the freed bit
for 'VM_NODUMP' flag.  The idea is is to add a new madvise() flag:
MADV_DONTDUMP, which can be set by applications to specifically request
memory regions which should not dump core.

The specific application I have in mind is qemu: we can add a flag there
that wouldn't dump all of guest memory when qemu dumps core.  This flag
might also be useful for security sensitive apps that want to absolutely
make sure that parts of memory are not dumped.  To clear the flag use:
MADV_DODUMP.

[akpm@linux-foundation.org: s/MADV_NODUMP/MADV_DONTDUMP/, s/MADV_CLEAR_NODUMP/MADV_DODUMP/, per Roland]
[akpm@linux-foundation.org: fix up the architectures which broke]
Signed-off-by: Jason Baron <jbaron@redhat.com>
Acked-by: Roland McGrath <roland@hack.frob.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Avi Kivity <avi@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23 16:58:42 -07:00
Jason Baron 909af768e8 coredump: remove VM_ALWAYSDUMP flag
The motivation for this patchset was that I was looking at a way for a
qemu-kvm process, to exclude the guest memory from its core dump, which
can be quite large.  There are already a number of filter flags in
/proc/<pid>/coredump_filter, however, these allow one to specify 'types'
of kernel memory, not specific address ranges (which is needed in this
case).

Since there are no more vma flags available, the first patch eliminates
the need for the 'VM_ALWAYSDUMP' flag.  The flag is used internally by
the kernel to mark vdso and vsyscall pages.  However, it is simple
enough to check if a vma covers a vdso or vsyscall page without the need
for this flag.

The second patch then replaces the 'VM_ALWAYSDUMP' flag with a new
'VM_NODUMP' flag, which can be set by userspace using new madvise flags:
'MADV_DONTDUMP', and unset via 'MADV_DODUMP'.  The core dump filters
continue to work the same as before unless 'MADV_DONTDUMP' is set on the
region.

The qemu code which implements this features is at:

  http://people.redhat.com/~jbaron/qemu-dump/qemu-dump.patch

In my testing the qemu core dump shrunk from 383MB -> 13MB with this
patch.

I also believe that the 'MADV_DONTDUMP' flag might be useful for
security sensitive apps, which might want to select which areas are
dumped.

This patch:

The VM_ALWAYSDUMP flag is currently used by the coredump code to
indicate that a vma is part of a vsyscall or vdso section.  However, we
can determine if a vma is in one these sections by checking it against
the gate_vma and checking for a non-NULL return value from
arch_vma_name().  Thus, freeing a valuable vma bit.

Signed-off-by: Jason Baron <jbaron@redhat.com>
Acked-by: Roland McGrath <roland@hack.frob.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Avi Kivity <avi@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23 16:58:42 -07:00
Namjae Jeon d533df07c2 fat: fix bug in enforcing Long File Name length
Since '*outlen' is initialized to zero, it is currently possible to
create a filename of length (FAT_LFN_LEN + 1) when utf8 is not enabled.
To enforce the FAT_LFN_LEN limit, we must perform one less iteration.

Signed-off-by: Namjae Jeon <linkinjeon@gmail.com>
Signed-off-by: Ravishankar N <cyberax82@gmail.com>
Acked-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23 16:58:40 -07:00
Namjae Jeon 41f0c02eac fat: clean up xlate_to_uni()
xlate_to_uni() is called by vfat_build_slots() with sbi->nls_io as the
final argument.  nls_io can never be null at this point because the
check is already being done in fat_fill_super() wherein the mount fails
if it is null.

Signed-off-by: Namjae Jeon <linkinjeon@gmail.com>
Signed-off-by: Ravishankar N <cyberax82@gmail.com>
Acked-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23 16:58:40 -07:00
Dan Carpenter da0503aae0 epoll: remove unneeded variable in reverse_path_check()
We never use the length variable.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23 16:58:38 -07:00
Steven Rostedt 02edc6fc4d epoll: comment the funky #ifdef
Looking for a bug in -rt, I stumbled across this code here from: commit
2dfa4eeab0 ("epoll keyed wakeups: teach epoll about hints coming with
the wakeup key"), specifically:

  #ifdef CONFIG_DEBUG_LOCK_ALLOC
  static inline void ep_wake_up_nested(wait_queue_head_t *wqueue,
                                      unsigned long events, int subclass)
  {
         unsigned long flags;

         spin_lock_irqsave_nested(&wqueue->lock, flags, subclass);
         wake_up_locked_poll(wqueue, events);
         spin_unlock_irqrestore(&wqueue->lock, flags);
  }
  #else
  static inline void ep_wake_up_nested(wait_queue_head_t *wqueue,
                                      unsigned long events, int subclass)
  {
         wake_up_poll(wqueue, events);
  }
  #endif

You change the function of ep_wake_up_nested() depending on whether
CONFIG_DEBUG_LOCK_ALLOC is set or not.  This looks awfully suspicious,
and there's no comment to explain why.  I initially thought that this
was trying to fool lockdep, and hiding a real bug.

Investigating it, I found the creation of wake_up_nested() (which no
longer exists) but was created for the sole purpose of epoll and its
strange wake ups, as explained in commit 0ccf831cbe ("lockdep:
annotate epoll")

Although the commit message says "annotate epoll" the change log is much
better at explaining what is happening than what is in the actual code.
Thus a comment is really necessary here.  And to save the time of other
developers from having to go trudging through the git logs trying to
figure out why this code exists.

I took parts of the change log and placed it into a comment above the
affected code.  This will make the description of what is happening more
visible to new developers that have to look at this code for the first
time.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Davide Libenzi <davidel@xmailserver.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23 16:58:38 -07:00
Hans Verkuil 626cf23660 poll: add poll_requested_events() and poll_does_not_wait() functions
In some cases the poll() implementation in a driver has to do different
things depending on the events the caller wants to poll for.  An example
is when a driver needs to start a DMA engine if the caller polls for
POLLIN, but doesn't want to do that if POLLIN is not requested but instead
only POLLOUT or POLLPRI is requested.  This is something that can happen
in the video4linux subsystem among others.

Unfortunately, the current epoll/poll/select implementation doesn't
provide that information reliably.  The poll_table_struct does have it: it
has a key field with the event mask.  But once a poll() call matches one
or more bits of that mask any following poll() calls are passed a NULL
poll_table pointer.

Also, the eventpoll implementation always left the key field at ~0 instead
of using the requested events mask.

This was changed in eventpoll.c so the key field now contains the actual
events that should be polled for as set by the caller.

The solution to the NULL poll_table pointer is to set the qproc field to
NULL in poll_table once poll() matches the events, not the poll_table
pointer itself.  That way drivers can obtain the mask through a new
poll_requested_events inline.

The poll_table_struct can still be NULL since some kernel code calls it
internally (netfs_state_poll() in ./drivers/staging/pohmelfs/netfs.h).  In
that case poll_requested_events() returns ~0 (i.e.  all events).

Very rarely drivers might want to know whether poll_wait will actually
wait.  If another earlier file descriptor in the set already matched the
events the caller wanted to wait for, then the kernel will return from the
select() call without waiting.  This might be useful information in order
to avoid doing expensive work.

A new helper function poll_does_not_wait() is added that drivers can use
to detect this situation.  This is now used in sock_poll_wait() in
include/net/sock.h.  This was the only place in the kernel that needed
this information.

Drivers should no longer access any of the poll_table internals, but use
the poll_requested_events() and poll_does_not_wait() access functions
instead.  In order to enforce that the poll_table fields are now prepended
with an underscore and a comment was added warning against using them
directly.

This required a change in unix_dgram_poll() in unix/af_unix.c which used
the key field to get the requested events.  It's been replaced by a call
to poll_requested_events().

For qproc it was especially important to change its name since the
behavior of that field changes with this patch since this function pointer
can now be NULL when that wasn't possible in the past.

Any driver accessing the qproc or key fields directly will now fail to compile.

Some notes regarding the correctness of this patch: the driver's poll()
function is called with a 'struct poll_table_struct *wait' argument.  This
pointer may or may not be NULL, drivers can never rely on it being one or
the other as that depends on whether or not an earlier file descriptor in
the select()'s fdset matched the requested events.

There are only three things a driver can do with the wait argument:

1) obtain the key field:

	events = wait ? wait->key : ~0;

   This will still work although it should be replaced with the new
   poll_requested_events() function (which does exactly the same).
   This will now even work better, since wait is no longer set to NULL
   unnecessarily.

2) use the qproc callback. This could be deadly since qproc can now be
   NULL. Renaming qproc should prevent this from happening. There are no
   kernel drivers that actually access this callback directly, BTW.

3) test whether wait == NULL to determine whether poll would return without
   waiting. This is no longer sufficient as the correct test is now
   wait == NULL || wait->_qproc == NULL.

   However, the worst that can happen here is a slight performance hit in
   the case where wait != NULL and wait->_qproc == NULL. In that case the
   driver will assume that poll_wait() will actually add the fd to the set
   of waiting file descriptors. Of course, poll_wait() will not do that
   since it tests for wait->_qproc. This will not break anything, though.

   There is only one place in the whole kernel where this happens
   (sock_poll_wait() in include/net/sock.h) and that code will be replaced
   by a call to poll_does_not_wait() in the next patch.

   Note that even if wait->_qproc != NULL drivers cannot rely on poll_wait()
   actually waiting. The next file descriptor from the set might match the
   event mask and thus any possible waits will never happen.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Reviewed-by: Jonathan Corbet <corbet@lwn.net>
Reviewed-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: Davide Libenzi <davidel@xmailserver.org>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Cc: Mauro Carvalho Chehab <mchehab@infradead.org>
Cc: David Miller <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23 16:58:38 -07:00
H Hartley Sweeten 9710a78e55 fs/notify/notification.c: make subsys_initcall function static
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Arun Sharma <asharma@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23 16:58:31 -07:00
Muthu Kumar b502bd1152 magic.h: move some FS magic numbers into magic.h
- Move open-coded filesystem magic numbers into magic.h

- Rearrange magic.h so that the filesystem-related constants are grouped
  together.

Signed-off-by: Muthukumar R <muthur@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23 16:58:31 -07:00
Linus Torvalds e57f146b28 - Improve error messages
- Clean-up i_nlink management
 - Minor clean-ups
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Merge tag 'upstream-3.4-rc1' of git://git.infradead.org/linux-ubifs

Pull UBIFS changes from Artem Bityutskiy:
 - Improve error messages
 - Clean-up i_nlink management
 - Minor clean-ups

* tag 'upstream-3.4-rc1' of git://git.infradead.org/linux-ubifs:
  UBIFS: improve error messages
  UBIFS: kill CUR_MAX_KEY_LEN macro
  UBIFS: do not use inc_link when i_nlink is zero
  UBIFS: make the dbg_lock spinlock static
  UBIFS: increase dumps loglevel
  UBIFS: amend recovery debugging message
2012-03-23 09:27:40 -07:00
Linus Torvalds 6e55f8ed81 One pstore patch
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Merge tag 'pstore-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux

Pull one pstore patch from Tony Luck

* tag 'pstore-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux:
  pstore: Introduce get_reason_str() to pstore
2012-03-23 09:24:07 -07:00
Linus Torvalds 49d99a2f9c Merge branch 'for-linus' of git://oss.sgi.com/xfs/xfs
Pull XFS updates from Ben Myers:
 "Scalability improvements for dquots, log grant code cleanups, plus
  bugfixes and cleanups large and small"

Fix up various trivial conflicts that were due to some of the earlier
patches already having been integrated into v3.3 as bugfixes, and then
there were development patches on top of those.  Easily merged by just
taking the newer version from the pulled branch.

* 'for-linus' of git://oss.sgi.com/xfs/xfs: (45 commits)
  xfs: fallback to vmalloc for large buffers in xfs_getbmap
  xfs: fallback to vmalloc for large buffers in xfs_attrmulti_attr_get
  xfs: remove remaining scraps of struct xfs_iomap
  xfs: fix inode lookup race
  xfs: clean up minor sparse warnings
  xfs: remove the global xfs_Gqm structure
  xfs: remove the per-filesystem list of dquots
  xfs: use per-filesystem radix trees for dquot lookup
  xfs: per-filesystem dquot LRU lists
  xfs: use common code for quota statistics
  xfs: reimplement fdatasync support
  xfs: split in-core and on-disk inode log item fields
  xfs: make xfs_inode_item_size idempotent
  xfs: log timestamp updates
  xfs: log file size updates at I/O completion time
  xfs: log file size updates as part of unwritten extent conversion
  xfs: do not require an ioend for new EOF calculation
  xfs: use per-filesystem I/O completion workqueues
  quota: make Q_XQUOTASYNC a noop
  xfs: include reservations in quota reporting
  ...
2012-03-23 09:19:22 -07:00
Linus Torvalds 1c3ddfe5ab Merge git://git.samba.org/sfrench/cifs-2.6
Pull CIFS fixes from Steve French

* git://git.samba.org/sfrench/cifs-2.6:
  cifs: clean up ordering in exit_cifs
  cifs: clean up call to cifs_dfs_release_automount_timer()
  CIFS: Delete echo_retries module parm
  CIFS: Prepare credits code for a slot reservation
  CIFS: Make wait_for_free_request killable
  CIFS: Introduce credit-based flow control
  CIFS: Simplify inFlight logic
  cifs: fix issue mounting of DFS ROOT when redirecting from one domain controller to the next
  CIFS: Respect negotiated MaxMpxCount
  CIFS: Fix a spurious error in cifs_push_posix_locks
2012-03-23 09:07:15 -07:00
Linus Torvalds f63d395d47 NFS client updates for Linux 3.4
New features include:
 - Add NFS client support for containers.
   This should enable most of the necessary functionality, including
   lockd support, and support for rpc.statd, NFSv4 idmapper and
   RPCSEC_GSS upcalls into the correct network namespace from
   which the mount system call was issued.
 - NFSv4 idmapper scalability improvements
   Base the idmapper cache on the keyring interface to allow concurrent
   access to idmapper entries. Start the process of migrating users from
   the single-threaded daemon-based approach to the multi-threaded
   request-key based approach.
 - NFSv4.1 implementation id.
   Allows the NFSv4.1 client and server to mutually identify each other
   for logging and debugging purposes.
 - Support the 'vers=4.1' mount option for mounting NFSv4.1 instead of
   having to use the more counterintuitive 'vers=4,minorversion=1'.
 - SUNRPC tracepoints.
   Start the process of adding tracepoints in order to improve debugging
   of the RPC layer.
 - pNFS object layout support for autologin.
 
 Important bugfixes include:
 - Fix a bug in rpc_wake_up/rpc_wake_up_status that caused them to fail
   to wake up all tasks when applied to priority waitqueues.
 - Ensure that we handle read delegations correctly, when we try to
   truncate a file.
 - A number of fixes for NFSv4 state manager loops (mostly to do with
   delegation recovery).
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Merge tag 'nfs-for-3.4-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

Pull NFS client updates for Linux 3.4 from Trond Myklebust:
 "New features include:
   - Add NFS client support for containers.

     This should enable most of the necessary functionality, including
     lockd support, and support for rpc.statd, NFSv4 idmapper and
     RPCSEC_GSS upcalls into the correct network namespace from which
     the mount system call was issued.

   - NFSv4 idmapper scalability improvements

     Base the idmapper cache on the keyring interface to allow
     concurrent access to idmapper entries.  Start the process of
     migrating users from the single-threaded daemon-based approach to
     the multi-threaded request-key based approach.

   - NFSv4.1 implementation id.

     Allows the NFSv4.1 client and server to mutually identify each
     other for logging and debugging purposes.

   - Support the 'vers=4.1' mount option for mounting NFSv4.1 instead of
     having to use the more counterintuitive 'vers=4,minorversion=1'.

   - SUNRPC tracepoints.

     Start the process of adding tracepoints in order to improve
     debugging of the RPC layer.

   - pNFS object layout support for autologin.

  Important bugfixes include:

   - Fix a bug in rpc_wake_up/rpc_wake_up_status that caused them to
     fail to wake up all tasks when applied to priority waitqueues.

   - Ensure that we handle read delegations correctly, when we try to
     truncate a file.

   - A number of fixes for NFSv4 state manager loops (mostly to do with
     delegation recovery)."

* tag 'nfs-for-3.4-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (224 commits)
  NFS: fix sb->s_id in nfs debug prints
  xprtrdma: Remove assumption that each segment is <= PAGE_SIZE
  xprtrdma: The transport should not bug-check when a dup reply is received
  pnfs-obj: autologin: Add support for protocol autologin
  NFS: Remove nfs4_setup_sequence from generic rename code
  NFS: Remove nfs4_setup_sequence from generic unlink code
  NFS: Remove nfs4_setup_sequence from generic read code
  NFS: Remove nfs4_setup_sequence from generic write code
  NFS: Fix more NFS debug related build warnings
  SUNRPC/LOCKD: Fix build warnings when CONFIG_SUNRPC_DEBUG is undefined
  nfs: non void functions must return a value
  SUNRPC: Kill compiler warning when RPC_DEBUG is unset
  SUNRPC/NFS: Add Kbuild dependencies for NFS_DEBUG/RPC_DEBUG
  NFS: Use cond_resched_lock() to reduce latencies in the commit scans
  NFSv4: It is not safe to dereference lsp->ls_state in release_lockowner
  NFS: ncommit count is being double decremented
  SUNRPC: We must not use list_for_each_entry_safe() in rpc_wake_up()
  Try using machine credentials for RENEW calls
  NFSv4.1: Fix a few issues in filelayout_commit_pagelist
  NFSv4.1: Clean ups and bugfixes for the pNFS read/writeback/commit code
  ...
2012-03-23 08:53:47 -07:00
Linus Torvalds aab008db80 Cleanups: rename of flush to invalidate, moving reporting of statistics
into debugfs, and use __read_mostly as neccessary.
 Also add a MAINTAINER file for cleancache API files.
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Merge tag 'stable/for-linus-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/mm

Pull cleancache changes from Konrad Rzeszutek Wilk:
 "This has some patches for the cleancache API that should have been
  submitted a _long_ time ago.  They are basically cleanups:

   - rename of flush to invalidate

   - moving reporting of statistics into debugfs

   - use __read_mostly as necessary.

  Oh, and also the MAINTAINERS file change.  The files (except the
  MAINTAINERS file) have been in #linux-next for months now.  The late
  addition of MAINTAINERS file is a brain-fart on my side - didn't
  realize I needed that just until I was typing this up - and I based
  that patch on v3.3 - so the tree is on top of v3.3."

* tag 'stable/for-linus-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/mm:
  MAINTAINERS: Adding cleancache API to the list.
  mm: cleancache: Use __read_mostly as appropiate.
  mm: cleancache: report statistics via debugfs instead of sysfs.
  mm: zcache/tmem/cleancache: s/flush/invalidate/
  mm: cleancache: s/flush/invalidate/
2012-03-22 19:52:47 -07:00
Linus Torvalds f7493e5d9c vfs: tidy up sparse warnings in fs/namei.c
While doing the fs/namei.c cleanups, I ran sparse on it, and it pointed
out other large integers and a couple of cases of us using '0' instead
of the proper 'NULL'.

Sparse still doesn't understand some of the conditional locking going
on, but that's no excuse for not fixing up the trivial stuff.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-22 16:10:40 -07:00
Linus Torvalds 989412bbd2 vfs: tidy up fs/namei.c byte-repeat word constants
In commit commit 1de5b41cd3 ("fs/namei.c: fix warnings on 32-bit")
Andrew said that there must be a tidier way of doing this.

This is that tidier way.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-22 15:58:27 -07:00
Randy Dunlap 1f1e6e523e fs: fix kernel-doc warnings in dcache.c
Fix kernel-doc warnings in fs/dcache.c:

  Warning(fs/dcache.c:1743): No description found for parameter 'seqp'
  Warning(fs/dcache.c:1743): Excess function parameter 'seq' description in '__d_lookup_rcu'

Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-22 15:49:18 -07:00
Al Viro f132c5be05 Fix full_name_hash() behaviour when length is a multiple of 8
We want it to match what hash_name() is doing, which means extra
multiply by 9 in this case...

Reported-and-Tested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-22 15:10:43 -07:00
Lucas De Marchi 4e474a00d7 sysctl: protect poll() in entries that may go away
Protect code accessing ctl_table by grabbing the header with grab_header()
and after releasing with sysctl_head_finish().  This is needed if poll()
is called in entries created by modules: currently only hostname and
domainname support poll(), but this bug may be triggered when/if modules
use it and if user called poll() in a file that doesn't support it.

Dave Jones reported the following when using a syscall fuzzer while
hibernating/resuming:

RIP: 0010:[<ffffffff81233e3e>]  [<ffffffff81233e3e>] proc_sys_poll+0x4e/0x90
RAX: 0000000000000145 RBX: ffff88020cab6940 RCX: 0000000000000000
RDX: ffffffff81233df0 RSI: 6b6b6b6b6b6b6b6b RDI: ffff88020cab6940
[ ... ]
Code: 00 48 89 fb 48 89 f1 48 8b 40 30 4c 8b 60 e8 b8 45 01 00 00 49 83
7c 24 28 00 74 2e 49 8b 74 24 30 48 85 f6 74 24 48 85 c9 75 32 <8b> 16
b8 45 01 00 00 48 63 d2 49 39 d5 74 10 8b 06 48 98 48 89

If an entry goes away while we are polling() it, ctl_table may not exist
anymore.

Reported-by: Dave Jones <davej@redhat.com>
Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2012-03-22 14:46:56 -07:00
Dave Chinner c999a223c2 xfs: introduce an allocation workqueue
We currently have significant issues with the amount of stack that
allocation in XFS uses, especially in the writeback path. We can
easily consume 4k of stack between mapping the page, manipulating
the bmap btree and allocating blocks from the free list. Not to
mention btree block readahead and other functionality that issues IO
in the allocation path.

As a result, we can no longer fit allocation in the writeback path
in the stack space provided on x86_64. To alleviate this problem,
introduce an allocation workqueue and move all allocations to a
seperate context. This can be easily added as an interposing layer
into xfs_alloc_vextent(), which takes a single argument structure
and does not return until the allocation is complete or has failed.

To do this, add a work structure and a completion to the allocation
args structure. This allows xfs_alloc_vextent to queue the args onto
the workqueue and wait for it to be completed by the worker. This
can be done completely transparently to the caller.

The worker function needs to ensure that it sets and clears the
PF_TRANS flag appropriately as it is being run in an active
transaction context. Work can also be queued in a memory reclaim
context, so a rescuer is needed for the workqueue.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-03-22 16:12:24 -05:00
Dave Chinner 1a1d772433 xfs: Fix open flag handling in open_by_handle code
Sparse identified some unsafe handling of open flags in the xfs open
by handle ioctl code. Update the code to use the correct access
macros to ensure that we handle the open flags correctly.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-03-22 15:56:52 -05:00
Kamal Dasu 5575acc780 xfs: fix deadlock in xfs_rtfree_extent
To fix the deadlock caused by repeatedly calling xfs_rtfree_extent

 - removed xfs_ilock() and xfs_trans_ijoin() from xfs_rtfree_extent(),
   instead added asserts that the inode is locked and has an inode_item
   attached to it.
 - in xfs_bunmapi() when dealing with an inode with the rt flag
   call xfs_ilock() and xfs_trans_ijoin() so that the
   reference count is bumped on the inode and attached it to the
   transaction before calling into xfs_bmap_del_extent, similar to
   what we do in xfs_bmap_rtalloc.

Signed-off-by: Kamal Dasu <kdasu.kdev@gmail.com>
Reviewed-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-03-22 15:31:06 -05:00
Gerard Snitselaar 1c2ccc66bc fs: xfs: fix section mismatch in linux-next
xfs_qm_exit() is called in init_xfs_fs().

Signed-off-by: Gerard Snitselaar <dev@snitselaar.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-03-22 13:48:55 -05:00
Linus Torvalds 95211279c5 Merge branch 'akpm' (Andrew's patch-bomb)
Merge first batch of patches from Andrew Morton:
 "A few misc things and all the MM queue"

* emailed from Andrew Morton <akpm@linux-foundation.org>: (92 commits)
  memcg: avoid THP split in task migration
  thp: add HPAGE_PMD_* definitions for !CONFIG_TRANSPARENT_HUGEPAGE
  memcg: clean up existing move charge code
  mm/memcontrol.c: remove unnecessary 'break' in mem_cgroup_read()
  mm/memcontrol.c: remove redundant BUG_ON() in mem_cgroup_usage_unregister_event()
  mm/memcontrol.c: s/stealed/stolen/
  memcg: fix performance of mem_cgroup_begin_update_page_stat()
  memcg: remove PCG_FILE_MAPPED
  memcg: use new logic for page stat accounting
  memcg: remove PCG_MOVE_LOCK flag from page_cgroup
  memcg: simplify move_account() check
  memcg: remove EXPORT_SYMBOL(mem_cgroup_update_page_stat)
  memcg: kill dead prev_priority stubs
  memcg: remove PCG_CACHE page_cgroup flag
  memcg: let css_get_next() rely upon rcu_read_lock()
  cgroup: revert ss_id_lock to spinlock
  idr: make idr_get_next() good for rcu_read_lock()
  memcg: remove unnecessary thp check in page stat accounting
  memcg: remove redundant returns
  memcg: enum lru_list lru
  ...
2012-03-22 09:04:48 -07:00
Alex Elder 3489b42a72 ceph: fix three bugs, two in ceph_vxattrcb_file_layout()
In ceph_vxattrcb_file_layout(), there is a check to determine
whether a preferred PG should be formatted into the output buffer.
That check assumes that a preferred PG number of 0 indicates "no
preference," but that is wrong.  No preference is indicated by a
negative (specifically, -1) PG number.

In addition, if that condition yields true, the preferred value
is formatted into a sized buffer, but the size consumed by the
earlier snprintf() call is not accounted for, opening up the
possibilty of a buffer overrun.

Finally, in ceph_vxattrcb_dir_rctime() where the nanoseconds part of
the time displayed did not include leading 0's, which led to
erroneous (sub-second portion of) time values being shown.

This fixes these three issues:
    http://tracker.newdream.net/issues/2155
    http://tracker.newdream.net/issues/2156
    http://tracker.newdream.net/issues/2157

Signed-off-by: Alex Elder <elder@dreamhost.com>
Reviewed-by: Sage Weil <sage@newdream.net>
2012-03-22 10:47:52 -05:00
Alex Elder cffaba15cd ceph: ensure Boolean options support both senses
Many ceph-related Boolean options offer the ability to both enable
and disable a feature.  For all those that don't offer this, add
a new option so that they do.

Note that ceph_show_options()--which reports mount options currently
in effect--only reports the option if it is different from the
default value.

Signed-off-by: Alex Elder <elder@dreamhost.com>
Signed-off-by: Sage Weil <sage@newdream.net>
2012-03-22 10:47:51 -05:00
Alex Elder ee57741c52 rbd: make ceph_parse_options() return a pointer
ceph_parse_options() takes the address of a pointer as an argument
and uses it to return the address of an allocated structure if
successful.  With this interface is not evident at call sites that
the pointer is always initialized.  Change the interface to return
the address instead (or a pointer-coded error code) to make the
validity of the returned pointer obvious.

Signed-off-by: Alex Elder <elder@dreamhost.com>
Signed-off-by: Sage Weil <sage@newdream.net>
2012-03-22 10:47:47 -05:00
Alex Elder 18fa8b3fea ceph: make ceph_setxattr() and ceph_removexattr() more alike
This patch just rearranges a few bits of code to make more
portions of ceph_setxattr() and ceph_removexattr() identical.

Signed-off-by: Alex Elder <elder@dreamhost.com>
Signed-off-by: Sage Weil <sage@newdream.net>
2012-03-22 10:47:46 -05:00
Alex Elder 3ce6cd1233 ceph: avoid repeatedly computing the size of constant vxattr names
All names defined in the directory and file virtual extended
attribute tables are constant, and the size of each is known at
compile time.  So there's no need to compute their length every
time any file's attribute is listed.

Record the length of each string and use it when needed to determine
the space need to represent them.  In addition, compute the
aggregate size of strings in each table just once at initialization
time.

Signed-off-by: Alex Elder <elder@dreamhost.com>
Signed-off-by: Sage Weil <sage@newdream.net>
2012-03-22 10:47:46 -05:00
Alex Elder aa4066ed7b ceph: encode type in vxattr callback routines
The names of the callback functions used for virtual extended
attributes are based only on the last component of the attribute
name.  Because of the way these are defined, this precludes allowing
a single (lowest) attribute name for different callbacks, dependent
on the type of file being operated on.  (For example, it might be
nice to support both "ceph.dir.layout" and "ceph.file.layout".)

Just change the callback names to avoid this problem.

Signed-off-by: Alex Elder <elder@dreamhost.com>
Signed-off-by: Sage Weil <sage@newdream.net>
2012-03-22 10:47:46 -05:00
Alex Elder 881a5fa200 ceph: drop "_cb" from name of struct ceph_vxattr_cb
A struct ceph_vxattr_cb does not represent a callback at all, but
rather a virtual extended attribute itself.  Drop the "_cb" suffix
from its name to reflect that.

Signed-off-by: Alex Elder <elder@dreamhost.com>
Signed-off-by: Sage Weil <sage@newdream.net>
2012-03-22 10:47:46 -05:00
Alex Elder eb78808446 ceph: use macros to normalize vxattr table definitions
Entries in the ceph virtual extended attribute tables all follow a
distinct pattern in their definition.  Enforce this pattern through
the use of a macro.

Also, a null name field signals the end of the table, so make that
be the first field in the ceph_vxattr_cb structure.

Signed-off-by: Alex Elder <elder@dreamhost.com>
Signed-off-by: Sage Weil <sage@newdream.net>
2012-03-22 10:47:46 -05:00
Alex Elder 2289190719 ceph: use a symbolic name for "ceph." extended attribute namespace
Use symbolic constants to define the top-level prefix for "ceph."
extended attribute names.

Signed-off-by: Alex Elder <elder@dreamhost.com>
Signed-off-by: Sage Weil <sage@newdream.net>
2012-03-22 10:47:46 -05:00
Alex Elder 06476a69d8 ceph: pass inode rather than table to ceph_match_vxattr()
All callers of ceph_match_vxattr() determine what to pass as the
first argument by calling ceph_inode_vxattrs(inode).  Just do that
inside ceph_match_vxattr() itself, changing it to take an inode
rather than the vxattr pointer as its first argument.

Also ensure the function works correctly for an empty table (i.e.,
containing only a terminating null entry).

Signed-off-by: Alex Elder <elder@dreamhost.com>
Signed-off-by: Sage Weil <sage@newdream.net>
2012-03-22 10:47:46 -05:00
Alex Elder b829c1954d ceph: don't null-terminate xattr values
For some reason, ceph_setxattr() allocates an extra byte in which a
'\0' is stored past the end of an extended attribute value.  This is
not needed, and is potentially misleading, so get rid of it.

Signed-off-by: Alex Elder <elder@dreamhost.com>
Signed-off-by: Sage Weil <sage@newdream.net>
2012-03-22 10:47:46 -05:00
Xi Wang 80834312a4 ceph: fix overflow check in build_snap_context()
The overflow check for a + n * b should be (n > (ULONG_MAX - a) / b),
rather than (n > ULONG_MAX / b - a).

Signed-off-by: Xi Wang <xi.wang@gmail.com>
Signed-off-by: Sage Weil <sage@newdream.net>
2012-03-22 10:47:45 -05:00
Xi Wang 810339ec2f ceph: avoid panic with mismatched symlink sizes in fill_inode()
Return -EINVAL rather than panic if iinfo->symlink_len and inode->i_size
do not match.

Also use kstrndup rather than kmalloc/memcpy.

Signed-off-by: Xi Wang <xi.wang@gmail.com>
Reviewed-by: Alex Elder <elder@dreamhost.com>
2012-03-22 10:47:45 -05:00
Amon Ott a661fc5611 ceph: use 2 instead of 1 as fallback for 32-bit inode number
The root directory of the Ceph mount has inode number 1, so falling back
to 1 always creates a collision. 2 is unused on my test systems and seems
less likely to collide.

Signed-off-by: Amon Ott <ao@m-privacy.de>
Signed-off-by: Sage Weil <sage@newdream.net>
2012-03-22 10:47:45 -05:00
Alex Elder 1ce208a6ce ceph: don't reset s_cap_ttl to zero
Avoid the need to check for a special zero s_cap_ttl value by just
using (jiffies - 1) as the value assigned to indicate "sometime in
the past."

Signed-off-by: Alex Elder <elder@dreamhost.com>
Reviewed-by: Sage Weil <sage@newdream.net>
2012-03-22 10:47:45 -05:00
Artem Bityutskiy 182f514f88 ext4: remove useless s_dirt assignment
Clean-up ext4 a tiny bit by removing useless s_dirt assignment in
'ext4_fill_super()' because a bit later we anyway call
'ext4_setup_super()' which writes the superblock to the media
unconditionally.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-03-21 22:30:06 -04:00
Artem Bityutskiy a8e25a8324 ext4: write superblock only once on unmount
In some rather rare cases it is possible that ext4 may the superblock
to the media twice. This patch makes sure this does not happen. This
should speed up unmounting in those cases.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-03-21 22:29:15 -04:00
Artem Bityutskiy 1b8b9750f0 ext4: do not mark superblock as dirty unnecessarily
Commit a0375156ca cleaned up superblock
dirtying handling, but missed one place. This patch does what was
intended: if we have the journal, then we update the superblock
through the journal rather than doing this directly.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-03-21 22:28:29 -04:00
Allison Henderson 7335519274 ext4: correct ext4_punch_hole return codes
ext4_punch_hole returns -ENOTSUPP but it should be using -EOPNOTSUPP

Signed-off-by: Allison Henderson <achender@linux.vnet.ibm.com>
Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-03-21 22:23:31 -04:00
Linus Torvalds 5375871d43 Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc
Pull powerpc merge from Benjamin Herrenschmidt:
 "Here's the powerpc batch for this merge window.  It is going to be a
  bit more nasty than usual as in touching things outside of
  arch/powerpc mostly due to the big iSeriesectomy :-) We finally got
  rid of the bugger (legacy iSeries support) which was a PITA to
  maintain and that nobody really used anymore.

  Here are some of the highlights:

   - Legacy iSeries is gone.  Thanks Stephen ! There's still some bits
     and pieces remaining if you do a grep -ir series arch/powerpc but
     they are harmless and will be removed in the next few weeks
     hopefully.

   - The 'fadump' functionality (Firmware Assisted Dump) replaces the
     previous (equivalent) "pHyp assisted dump"...  it's a rewrite of a
     mechanism to get the hypervisor to do crash dumps on pSeries, the
     new implementation hopefully being much more reliable.  Thanks
     Mahesh Salgaonkar.

   - The "EEH" code (pSeries PCI error handling & recovery) got a big
     spring cleaning, motivated by the need to be able to implement a
     new backend for it on top of some new different type of firwmare.

     The work isn't complete yet, but a good chunk of the cleanups is
     there.  Note that this adds a field to struct device_node which is
     not very nice and which Grant objects to.  I will have a patch soon
     that moves that to a powerpc private data structure (hopefully
     before rc1) and we'll improve things further later on (hopefully
     getting rid of the need for that pointer completely).  Thanks Gavin
     Shan.

   - I dug into our exception & interrupt handling code to improve the
     way we do lazy interrupt handling (and make it work properly with
     "edge" triggered interrupt sources), and while at it found & fixed
     a wagon of issues in those areas, including adding support for page
     fault retry & fatal signals on page faults.

   - Your usual random batch of small fixes & updates, including a bunch
     of new embedded boards, both Freescale and APM based ones, etc..."

I fixed up some conflicts with the generalized irq-domain changes from
Grant Likely, hopefully correctly.

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (141 commits)
  powerpc/ps3: Do not adjust the wrapper load address
  powerpc: Remove the rest of the legacy iSeries include files
  powerpc: Remove the remaining CONFIG_PPC_ISERIES pieces
  init: Remove CONFIG_PPC_ISERIES
  powerpc: Remove FW_FEATURE ISERIES from arch code
  tty/hvc_vio: FW_FEATURE_ISERIES is no longer selectable
  powerpc/spufs: Fix double unlocks
  powerpc/5200: convert mpc5200 to use of_platform_populate()
  powerpc/mpc5200: add options to mpc5200_defconfig
  powerpc/mpc52xx: add a4m072 board support
  powerpc/mpc5200: update mpc5200_defconfig to fit for charon board
  Documentation/powerpc/mpc52xx.txt: Checkpatch cleanup
  powerpc/44x: Add additional device support for APM821xx SoC and Bluestone board
  powerpc/44x: Add support PCI-E for APM821xx SoC and Bluestone board
  MAINTAINERS: Update PowerPC 4xx tree
  powerpc/44x: The bug fixed support for APM821xx SoC and Bluestone board
  powerpc: document the FSL MPIC message register binding
  powerpc: add support for MPIC message register API
  powerpc/fsl: Added aliased MSIIR register address to MSI node in dts
  powerpc/85xx: mpc8548cds - add 36-bit dts
  ...
2012-03-21 18:55:10 -07:00
Lukas Czerner afcff5d80a ext4: remove restrictive checks for EOFBLOCKS_FL
We are going to remove the EOFBLOCKS_FL flag in the future, so this is
the first part of the removal. We can not remove it entirely just now,
since the e2fsck is still checking for it and it might cause headache to
some people. Instead, remove the restrictive checks now and the rest
later, when the new e2fsck code is out and common enough.

This is also needed because punch hole already breaks the EOFBLOCKS_FL
semantics, so it might cause the some troubles. So simply remove it.

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-03-21 21:47:55 -04:00
Lukas Czerner a7967f055a ext4: always set then trimmed blocks count into len
Currently if the range to trim is too small, for example on 1K fs
the request to trim the first block, then the 'range->len' is not set
reporting wrong number of discarded block to the caller.

Fix this by always setting the 'range->len' before we return. Note that
when there is a failure (-EINVAL) caller can not depend on 'range->len'
being set properly.

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-03-21 21:26:22 -04:00
Lukas Czerner 21e7fd22a5 ext4: fix trimmed block count accunting
Currently when there is not enough free blocks in the block group to
discard (grp->bb_free < minlen) the 'trimmed' is bumped up anyway with
the number of discarded blocks from the previous iteration. Fix this
by bumping up 'trimmed' only if the ext4_trim_all_free() was actually
run.

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-03-21 21:24:22 -04:00
Lukas Czerner 913eed83ed ext4: fix start and len arguments handling in ext4_trim_fs()
The overflow can happen when we are calling get_group_no_and_offset()
which stores the group number in the ext4_grpblk_t type which is
actually int. However when the blocknr is big enough the group number
might be bigger than ext4_grpblk_t resulting in overflow. This will
most likely happen with FITRIM default argument len = ULLONG_MAX.

Fix this by using "end" variable instead of "start+len" as it is easier
to get right and specifically check that the end is not beyond the end
of the file system, so we are sure that the result of
get_group_no_and_offset() will not overflow. Otherwise truncate it to
the size of the file system.

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-03-21 21:22:22 -04:00
Linus Torvalds ad12ab259d Merge git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-3.0-nmw
Pull gfs2 changes from Steven Whitehouse.

* git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-3.0-nmw:
  GFS2: Change truncate page allocation to be GFP_NOFS
  GFS2: call gfs2_write_alloc_required for each chunk
  GFS2: Clean up log flush header writing
  GFS2: Remove a __GFP_NOFAIL allocation
  GFS2: Flush pending glock work when evicting an inode
  GFS2: make sure rgrps are up to date in func gfs2_blk2rgrpd
  GFS2: Eliminate sd_rindex_mutex
  GFS2: Unlock rindex mutex on glock error
  GFS2: Make bd_cmp() static
  GFS2: Sort the ordered write list
  GFS2: FITRIM ioctl support
  GFS2: Move two functions from log.c to lops.c
  GFS2: glock statistics gathering
2012-03-21 18:00:03 -07:00
Hillf Danton d1d5e05ffd hugetlbfs: return error code when initializing module
Return an errno upon failure to create inode kmem cache, and unregister
the FS upon failure to mount.

[akpm@linux-foundation.org: remove unneeded test of `error']
Signed-off-by: Hillf Danton <dhillf@gmail.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-21 17:55:00 -07:00
Steven Truelove 40716e2924 hugetlbfs: fix alignment of huge page requests
When calling shmget() with SHM_HUGETLB, shmget aligns the request size to
PAGE_SIZE, but this is not sufficient.

Modify hugetlb_file_setup() to align requests to the huge page size, and
to accept an address argument so that all alignment checks can be
performed in hugetlb_file_setup(), rather than in its callers.  Change
newseg() and mmap_pgoff() to match the new prototype and eliminate a now
redundant alignment check.

[akpm@linux-foundation.org: fix build]
Signed-off-by: Steven Truelove <steven.truelove@utoronto.ca>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-21 17:54:59 -07:00
David Rientjes 21a3c273f8 mm, hugetlb: add thread name and pid to SHM_HUGETLB mlock rlimit warning
Add the thread name and pid of the application that is allocating shm
segments with MAP_HUGETLB without being a part of
/proc/sys/vm/hugetlb_shm_group or having CAP_IPC_LOCK.

This identifies the application so it may be fixed by avoiding using the
deprecated exception (see Documentation/feature-removal-schedule.txt).

Signed-off-by: David Rientjes <rientjes@google.com>
Cc: Dave Jones <davej@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-21 17:54:59 -07:00
David Rientjes 05af2e104a mm, counters: remove task argument to sync_mm_rss() and __sync_task_rss_stat()
sync_mm_rss() can only be used for current to avoid race conditions in
iterating and clearing its per-task counters.  Remove the task argument
for it and its helper function, __sync_task_rss_stat(), to avoid thinking
it can be used safely for anything other than current.

Signed-off-by: David Rientjes <rientjes@google.com>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-21 17:54:59 -07:00
David Gibson 90481622d7 hugepages: fix use after free bug in "quota" handling
hugetlbfs_{get,put}_quota() are badly named.  They don't interact with the
general quota handling code, and they don't much resemble its behaviour.
Rather than being about maintaining limits on on-disk block usage by
particular users, they are instead about maintaining limits on in-memory
page usage (including anonymous MAP_PRIVATE copied-on-write pages)
associated with a particular hugetlbfs filesystem instance.

Worse, they work by having callbacks to the hugetlbfs filesystem code from
the low-level page handling code, in particular from free_huge_page().
This is a layering violation of itself, but more importantly, if the
kernel does a get_user_pages() on hugepages (which can happen from KVM
amongst others), then the free_huge_page() can be delayed until after the
associated inode has already been freed.  If an unmount occurs at the
wrong time, even the hugetlbfs superblock where the "quota" limits are
stored may have been freed.

Andrew Barry proposed a patch to fix this by having hugepages, instead of
storing a pointer to their address_space and reaching the superblock from
there, had the hugepages store pointers directly to the superblock,
bumping the reference count as appropriate to avoid it being freed.
Andrew Morton rejected that version, however, on the grounds that it made
the existing layering violation worse.

This is a reworked version of Andrew's patch, which removes the extra, and
some of the existing, layering violation.  It works by introducing the
concept of a hugepage "subpool" at the lower hugepage mm layer - that is a
finite logical pool of hugepages to allocate from.  hugetlbfs now creates
a subpool for each filesystem instance with a page limit set, and a
pointer to the subpool gets added to each allocated hugepage, instead of
the address_space pointer used now.  The subpool has its own lifetime and
is only freed once all pages in it _and_ all other references to it (i.e.
superblocks) are gone.

subpools are optional - a NULL subpool pointer is taken by the code to
mean that no subpool limits are in effect.

Previous discussion of this bug found in:  "Fix refcounting in hugetlbfs
quota handling.". See:  https://lkml.org/lkml/2011/8/11/28 or
http://marc.info/?l=linux-mm&m=126928970510627&w=1

v2: Fixed a bug spotted by Hillf Danton, and removed the extra parameter to
alloc_huge_page() - since it already takes the vma, it is not necessary.

Signed-off-by: Andrew Barry <abarry@cray.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Cc: Hugh Dickins <hughd@google.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: Hillf Danton <dhillf@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-21 17:54:59 -07:00
David Gibson a1d776ee31 hugetlb: cleanup hugetlb.h
Make a couple of small cleanups to linux/include/hugetlb.h.  The
set_file_hugepages() function, which was not used anywhere is removed,
and the hugetlbfs_config and hugetlbfs_inode_info structures with its
HUGETLBFS_I helper function are moved into inode.c, the only place they
were used.

These structures are really linked to the hugetlbfs filesystem
specifically not to hugepage mm handling in general, so they belong in
the filesystem code not in a generally available header.

It would be nice to move the hugetlbfs_sb_info (superblock) structure in
there as well, but it's currently needed in a number of places via the
hstate_vma() and hstate_inode().

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Cc: Hugh Dickins <hughd@google.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Andrew Barry <abarry@cray.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: Hillf Danton <dhillf@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-21 17:54:59 -07:00
Aneesh Kumar K.V a05b0855fd hugetlbfs: avoid taking i_mutex from hugetlbfs_read()
Taking i_mutex in hugetlbfs_read() can result in deadlock with mmap as
explained below

 Thread A:
  read() on hugetlbfs
   hugetlbfs_read() called
    i_mutex grabbed
     hugetlbfs_read_actor() called
      __copy_to_user() called
       page fault is triggered
 Thread B, sharing address space with A:
  mmap() the same file
   ->mmap_sem is grabbed on task_B->mm->mmap_sem
    hugetlbfs_file_mmap() is called
     attempt to grab ->i_mutex and block waiting for A to give it up
 Thread A:
  pagefault handled blocked on attempt to grab task_A->mm->mmap_sem,
 which happens to be the same thing as task_B->mm->mmap_sem.  Block waiting
 for B to give it up.

AFAIU the i_mutex locking was added to hugetlbfs_read() as per
http://lkml.indiana.edu/hypermail/linux/kernel/0707.2/3066.html to take
care of the race between truncate and read.  This patch fixes this by
looking at page->mapping under lock_page() (find_lock_page()) to ensure
that the inode didn't get truncated in the range during a parallel read.

Ideally we can extend the patch to make sure we don't increase i_size in
mmap.  But that will break userspace, because applications will now have
to use truncate(2) to increase i_size in hugetlbfs.

Based on the original patch from Hillf Danton.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Hillf Danton <dhillf@gmail.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Hugh Dickins <hughd@google.com>
Cc: <stable@kernel.org>		[everything after 2007 :)]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-21 17:54:58 -07:00
Siddhesh Poyarekar b76437579d procfs: mark thread stack correctly in proc/<pid>/maps
Stack for a new thread is mapped by userspace code and passed via
sys_clone.  This memory is currently seen as anonymous in
/proc/<pid>/maps, which makes it difficult to ascertain which mappings
are being used for thread stacks.  This patch uses the individual task
stack pointers to determine which vmas are actually thread stacks.

For a multithreaded program like the following:

	#include <pthread.h>

	void *thread_main(void *foo)
	{
		while(1);
	}

	int main()
	{
		pthread_t t;
		pthread_create(&t, NULL, thread_main, NULL);
		pthread_join(t, NULL);
	}

proc/PID/maps looks like the following:

    00400000-00401000 r-xp 00000000 fd:0a 3671804                            /home/siddhesh/a.out
    00600000-00601000 rw-p 00000000 fd:0a 3671804                            /home/siddhesh/a.out
    019ef000-01a10000 rw-p 00000000 00:00 0                                  [heap]
    7f8a44491000-7f8a44492000 ---p 00000000 00:00 0
    7f8a44492000-7f8a44c92000 rw-p 00000000 00:00 0
    7f8a44c92000-7f8a44e3d000 r-xp 00000000 fd:00 2097482                    /lib64/libc-2.14.90.so
    7f8a44e3d000-7f8a4503d000 ---p 001ab000 fd:00 2097482                    /lib64/libc-2.14.90.so
    7f8a4503d000-7f8a45041000 r--p 001ab000 fd:00 2097482                    /lib64/libc-2.14.90.so
    7f8a45041000-7f8a45043000 rw-p 001af000 fd:00 2097482                    /lib64/libc-2.14.90.so
    7f8a45043000-7f8a45048000 rw-p 00000000 00:00 0
    7f8a45048000-7f8a4505f000 r-xp 00000000 fd:00 2099938                    /lib64/libpthread-2.14.90.so
    7f8a4505f000-7f8a4525e000 ---p 00017000 fd:00 2099938                    /lib64/libpthread-2.14.90.so
    7f8a4525e000-7f8a4525f000 r--p 00016000 fd:00 2099938                    /lib64/libpthread-2.14.90.so
    7f8a4525f000-7f8a45260000 rw-p 00017000 fd:00 2099938                    /lib64/libpthread-2.14.90.so
    7f8a45260000-7f8a45264000 rw-p 00000000 00:00 0
    7f8a45264000-7f8a45286000 r-xp 00000000 fd:00 2097348                    /lib64/ld-2.14.90.so
    7f8a45457000-7f8a4545a000 rw-p 00000000 00:00 0
    7f8a45484000-7f8a45485000 rw-p 00000000 00:00 0
    7f8a45485000-7f8a45486000 r--p 00021000 fd:00 2097348                    /lib64/ld-2.14.90.so
    7f8a45486000-7f8a45487000 rw-p 00022000 fd:00 2097348                    /lib64/ld-2.14.90.so
    7f8a45487000-7f8a45488000 rw-p 00000000 00:00 0
    7fff6273b000-7fff6275c000 rw-p 00000000 00:00 0                          [stack]
    7fff627ff000-7fff62800000 r-xp 00000000 00:00 0                          [vdso]
    ffffffffff600000-ffffffffff601000 r-xp 00000000 00:00 0                  [vsyscall]

Here, one could guess that 7f8a44492000-7f8a44c92000 is a stack since
the earlier vma that has no permissions (7f8a44e3d000-7f8a4503d000) but
that is not always a reliable way to find out which vma is a thread
stack.  Also, /proc/PID/maps and /proc/PID/task/TID/maps has the same
content.

With this patch in place, /proc/PID/task/TID/maps are treated as 'maps
as the task would see it' and hence, only the vma that that task uses as
stack is marked as [stack].  All other 'stack' vmas are marked as
anonymous memory.  /proc/PID/maps acts as a thread group level view,
where all thread stack vmas are marked as [stack:TID] where TID is the
process ID of the task that uses that vma as stack, while the process
stack is marked as [stack].

So /proc/PID/maps will look like this:

    00400000-00401000 r-xp 00000000 fd:0a 3671804                            /home/siddhesh/a.out
    00600000-00601000 rw-p 00000000 fd:0a 3671804                            /home/siddhesh/a.out
    019ef000-01a10000 rw-p 00000000 00:00 0                                  [heap]
    7f8a44491000-7f8a44492000 ---p 00000000 00:00 0
    7f8a44492000-7f8a44c92000 rw-p 00000000 00:00 0                          [stack:1442]
    7f8a44c92000-7f8a44e3d000 r-xp 00000000 fd:00 2097482                    /lib64/libc-2.14.90.so
    7f8a44e3d000-7f8a4503d000 ---p 001ab000 fd:00 2097482                    /lib64/libc-2.14.90.so
    7f8a4503d000-7f8a45041000 r--p 001ab000 fd:00 2097482                    /lib64/libc-2.14.90.so
    7f8a45041000-7f8a45043000 rw-p 001af000 fd:00 2097482                    /lib64/libc-2.14.90.so
    7f8a45043000-7f8a45048000 rw-p 00000000 00:00 0
    7f8a45048000-7f8a4505f000 r-xp 00000000 fd:00 2099938                    /lib64/libpthread-2.14.90.so
    7f8a4505f000-7f8a4525e000 ---p 00017000 fd:00 2099938                    /lib64/libpthread-2.14.90.so
    7f8a4525e000-7f8a4525f000 r--p 00016000 fd:00 2099938                    /lib64/libpthread-2.14.90.so
    7f8a4525f000-7f8a45260000 rw-p 00017000 fd:00 2099938                    /lib64/libpthread-2.14.90.so
    7f8a45260000-7f8a45264000 rw-p 00000000 00:00 0
    7f8a45264000-7f8a45286000 r-xp 00000000 fd:00 2097348                    /lib64/ld-2.14.90.so
    7f8a45457000-7f8a4545a000 rw-p 00000000 00:00 0
    7f8a45484000-7f8a45485000 rw-p 00000000 00:00 0
    7f8a45485000-7f8a45486000 r--p 00021000 fd:00 2097348                    /lib64/ld-2.14.90.so
    7f8a45486000-7f8a45487000 rw-p 00022000 fd:00 2097348                    /lib64/ld-2.14.90.so
    7f8a45487000-7f8a45488000 rw-p 00000000 00:00 0
    7fff6273b000-7fff6275c000 rw-p 00000000 00:00 0                          [stack]
    7fff627ff000-7fff62800000 r-xp 00000000 00:00 0                          [vdso]
    ffffffffff600000-ffffffffff601000 r-xp 00000000 00:00 0                  [vsyscall]

Thus marking all vmas that are used as stacks by the threads in the
thread group along with the process stack.  The task level maps will
however like this:

    00400000-00401000 r-xp 00000000 fd:0a 3671804                            /home/siddhesh/a.out
    00600000-00601000 rw-p 00000000 fd:0a 3671804                            /home/siddhesh/a.out
    019ef000-01a10000 rw-p 00000000 00:00 0                                  [heap]
    7f8a44491000-7f8a44492000 ---p 00000000 00:00 0
    7f8a44492000-7f8a44c92000 rw-p 00000000 00:00 0                          [stack]
    7f8a44c92000-7f8a44e3d000 r-xp 00000000 fd:00 2097482                    /lib64/libc-2.14.90.so
    7f8a44e3d000-7f8a4503d000 ---p 001ab000 fd:00 2097482                    /lib64/libc-2.14.90.so
    7f8a4503d000-7f8a45041000 r--p 001ab000 fd:00 2097482                    /lib64/libc-2.14.90.so
    7f8a45041000-7f8a45043000 rw-p 001af000 fd:00 2097482                    /lib64/libc-2.14.90.so
    7f8a45043000-7f8a45048000 rw-p 00000000 00:00 0
    7f8a45048000-7f8a4505f000 r-xp 00000000 fd:00 2099938                    /lib64/libpthread-2.14.90.so
    7f8a4505f000-7f8a4525e000 ---p 00017000 fd:00 2099938                    /lib64/libpthread-2.14.90.so
    7f8a4525e000-7f8a4525f000 r--p 00016000 fd:00 2099938                    /lib64/libpthread-2.14.90.so
    7f8a4525f000-7f8a45260000 rw-p 00017000 fd:00 2099938                    /lib64/libpthread-2.14.90.so
    7f8a45260000-7f8a45264000 rw-p 00000000 00:00 0
    7f8a45264000-7f8a45286000 r-xp 00000000 fd:00 2097348                    /lib64/ld-2.14.90.so
    7f8a45457000-7f8a4545a000 rw-p 00000000 00:00 0
    7f8a45484000-7f8a45485000 rw-p 00000000 00:00 0
    7f8a45485000-7f8a45486000 r--p 00021000 fd:00 2097348                    /lib64/ld-2.14.90.so
    7f8a45486000-7f8a45487000 rw-p 00022000 fd:00 2097348                    /lib64/ld-2.14.90.so
    7f8a45487000-7f8a45488000 rw-p 00000000 00:00 0
    7fff6273b000-7fff6275c000 rw-p 00000000 00:00 0
    7fff627ff000-7fff62800000 r-xp 00000000 00:00 0                          [vdso]
    ffffffffff600000-ffffffffff601000 r-xp 00000000 00:00 0                  [vsyscall]

where only the vma that is being used as a stack by *that* task is
marked as [stack].

Analogous changes have been made to /proc/PID/smaps,
/proc/PID/numa_maps, /proc/PID/task/TID/smaps and
/proc/PID/task/TID/numa_maps. Relevant snippets from smaps and
numa_maps:

    [siddhesh@localhost ~ ]$ pgrep a.out
    1441
    [siddhesh@localhost ~ ]$ cat /proc/1441/smaps | grep "\[stack"
    7f8a44492000-7f8a44c92000 rw-p 00000000 00:00 0                          [stack:1442]
    7fff6273b000-7fff6275c000 rw-p 00000000 00:00 0                          [stack]
    [siddhesh@localhost ~ ]$ cat /proc/1441/task/1442/smaps | grep "\[stack"
    7f8a44492000-7f8a44c92000 rw-p 00000000 00:00 0                          [stack]
    [siddhesh@localhost ~ ]$ cat /proc/1441/task/1441/smaps | grep "\[stack"
    7fff6273b000-7fff6275c000 rw-p 00000000 00:00 0                          [stack]
    [siddhesh@localhost ~ ]$ cat /proc/1441/numa_maps | grep "stack"
    7f8a44492000 default stack:1442 anon=2 dirty=2 N0=2
    7fff6273a000 default stack anon=3 dirty=3 N0=3
    [siddhesh@localhost ~ ]$ cat /proc/1441/task/1442/numa_maps | grep "stack"
    7f8a44492000 default stack anon=2 dirty=2 N0=2
    [siddhesh@localhost ~ ]$ cat /proc/1441/task/1441/numa_maps | grep "stack"
    7fff6273a000 default stack anon=3 dirty=3 N0=3

[akpm@linux-foundation.org: checkpatch fixes]
[akpm@linux-foundation.org: fix build]
Signed-off-by: Siddhesh Poyarekar <siddhesh.poyarekar@gmail.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@gmail.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Jamie Lokier <jamie@shareable.org>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Matt Mackall <mpm@selenic.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-21 17:54:58 -07:00
Naoya Horiguchi 092b50bacd pagemap: introduce data structure for pagemap entry
Currently a local variable of pagemap entry in pagemap_pte_range() is
named pfn and typed with u64, but it's not correct (pfn should be unsigned
long.)

This patch introduces special type for pagemap entries and replaces code
with it.

Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-21 17:54:57 -07:00
Naoya Horiguchi e873c49fbf pagemap: export KPF_THP
This flag shows that a given page is a subpage of a transparent hugepage.
It helps us debug and test the kernel by showing physical address of thp.

Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Reviewed-by: Wu Fengguang <fengguang.wu@intel.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-21 17:54:57 -07:00
Naoya Horiguchi 025c5b2451 thp: optimize away unnecessary page table locking
Currently when we check if we can handle thp as it is or we need to split
it into regular sized pages, we hold page table lock prior to check
whether a given pmd is mapping thp or not.  Because of this, when it's not
"huge pmd" we suffer from unnecessary lock/unlock overhead.  To remove it,
this patch introduces a optimized check function and replace several
similar logics with it.

[akpm@linux-foundation.org: checkpatch fixes]
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-21 17:54:57 -07:00
Naoya Horiguchi 5aaabe831e pagemap: avoid splitting thp when reading /proc/pid/pagemap
Thp split is not necessary if we explicitly check whether pmds are mapping
thps or not.  This patch introduces this check and adds code to generate
pagemap entries for pmds mapping thps, which results in less performance
impact of pagemap on thp.

Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-21 17:54:56 -07:00
Xiao Guangrong 4bfc130d5a hugetlbfs: fix hugetlb_get_unmapped_area()
Use/update cached_hole_size and free_area_cache properly to speedup
finding of a free region.

Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Hillf Danton <dhillf@gmail.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-21 17:54:56 -07:00
Earl Chew 7904ac8424 seq_file: fix mishandling of consecutive pread() invocations.
The following program illustrates the problem:

    char buf[8192];

    int fd = open("/proc/self/maps", O_RDONLY);

    n = pread(fd, buf, sizeof(buf), 0);
    printf("%d\n", n);

    /* lseek(fd, 0, SEEK_CUR); */ /* Uncomment to work around */

    n = pread(fd, buf, sizeof(buf), 0);
    printf("%d\n", n);

The second printf() prints zero, but uncommenting the lseek() corrects its
behaviour.

To fix, make seq_read() mirror seq_lseek() when processing changes in
*ppos.  Restore m->version first, then if required traverse and update
read_pos on success.

Addresses https://bugzilla.kernel.org/show_bug.cgi?id=11856

Signed-off-by: Earl Chew <echew@ixiacom.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>
2012-03-21 17:54:54 -07:00
Andrew Morton 1de5b41cd3 fs/namei.c: fix warnings on 32-bit
i386 allnoconfig:

  fs/namei.c: In function 'has_zero':
  fs/namei.c:1617: warning: integer constant is too large for 'unsigned long' type
  fs/namei.c:1617: warning: integer constant is too large for 'unsigned long' type
  fs/namei.c: In function 'hash_name':
  fs/namei.c:1635: warning: integer constant is too large for 'unsigned long' type

There must be a tidier way of doing this.

Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-21 17:54:54 -07:00
Andrea Arcangeli 1a5a9906d4 mm: thp: fix pmd_bad() triggering in code paths holding mmap_sem read mode
In some cases it may happen that pmd_none_or_clear_bad() is called with
the mmap_sem hold in read mode.  In those cases the huge page faults can
allocate hugepmds under pmd_none_or_clear_bad() and that can trigger a
false positive from pmd_bad() that will not like to see a pmd
materializing as trans huge.

It's not khugepaged causing the problem, khugepaged holds the mmap_sem
in write mode (and all those sites must hold the mmap_sem in read mode
to prevent pagetables to go away from under them, during code review it
seems vm86 mode on 32bit kernels requires that too unless it's
restricted to 1 thread per process or UP builds).  The race is only with
the huge pagefaults that can convert a pmd_none() into a
pmd_trans_huge().

Effectively all these pmd_none_or_clear_bad() sites running with
mmap_sem in read mode are somewhat speculative with the page faults, and
the result is always undefined when they run simultaneously.  This is
probably why it wasn't common to run into this.  For example if the
madvise(MADV_DONTNEED) runs zap_page_range() shortly before the page
fault, the hugepage will not be zapped, if the page fault runs first it
will be zapped.

Altering pmd_bad() not to error out if it finds hugepmds won't be enough
to fix this, because zap_pmd_range would then proceed to call
zap_pte_range (which would be incorrect if the pmd become a
pmd_trans_huge()).

The simplest way to fix this is to read the pmd in the local stack
(regardless of what we read, no need of actual CPU barriers, only
compiler barrier needed), and be sure it is not changing under the code
that computes its value.  Even if the real pmd is changing under the
value we hold on the stack, we don't care.  If we actually end up in
zap_pte_range it means the pmd was not none already and it was not huge,
and it can't become huge from under us (khugepaged locking explained
above).

All we need is to enforce that there is no way anymore that in a code
path like below, pmd_trans_huge can be false, but pmd_none_or_clear_bad
can run into a hugepmd.  The overhead of a barrier() is just a compiler
tweak and should not be measurable (I only added it for THP builds).  I
don't exclude different compiler versions may have prevented the race
too by caching the value of *pmd on the stack (that hasn't been
verified, but it wouldn't be impossible considering
pmd_none_or_clear_bad, pmd_bad, pmd_trans_huge, pmd_none are all inlines
and there's no external function called in between pmd_trans_huge and
pmd_none_or_clear_bad).

		if (pmd_trans_huge(*pmd)) {
			if (next-addr != HPAGE_PMD_SIZE) {
				VM_BUG_ON(!rwsem_is_locked(&tlb->mm->mmap_sem));
				split_huge_page_pmd(vma->vm_mm, pmd);
			} else if (zap_huge_pmd(tlb, vma, pmd, addr))
				continue;
			/* fall through */
		}
		if (pmd_none_or_clear_bad(pmd))

Because this race condition could be exercised without special
privileges this was reported in CVE-2012-1179.

The race was identified and fully explained by Ulrich who debugged it.
I'm quoting his accurate explanation below, for reference.

====== start quote =======
      mapcount 0 page_mapcount 1
      kernel BUG at mm/huge_memory.c:1384!

    At some point prior to the panic, a "bad pmd ..." message similar to the
    following is logged on the console:

      mm/memory.c:145: bad pmd ffff8800376e1f98(80000000314000e7).

    The "bad pmd ..." message is logged by pmd_clear_bad() before it clears
    the page's PMD table entry.

        143 void pmd_clear_bad(pmd_t *pmd)
        144 {
    ->  145         pmd_ERROR(*pmd);
        146         pmd_clear(pmd);
        147 }

    After the PMD table entry has been cleared, there is an inconsistency
    between the actual number of PMD table entries that are mapping the page
    and the page's map count (_mapcount field in struct page). When the page
    is subsequently reclaimed, __split_huge_page() detects this inconsistency.

       1381         if (mapcount != page_mapcount(page))
       1382                 printk(KERN_ERR "mapcount %d page_mapcount %d\n",
       1383                        mapcount, page_mapcount(page));
    -> 1384         BUG_ON(mapcount != page_mapcount(page));

    The root cause of the problem is a race of two threads in a multithreaded
    process. Thread B incurs a page fault on a virtual address that has never
    been accessed (PMD entry is zero) while Thread A is executing an madvise()
    system call on a virtual address within the same 2 MB (huge page) range.

               virtual address space
              .---------------------.
              |                     |
              |                     |
            .-|---------------------|
            | |                     |
            | |                     |<-- B(fault)
            | |                     |
      2 MB  | |/////////////////////|-.
      huge <  |/////////////////////|  > A(range)
      page  | |/////////////////////|-'
            | |                     |
            | |                     |
            '-|---------------------|
              |                     |
              |                     |
              '---------------------'

    - Thread A is executing an madvise(..., MADV_DONTNEED) system call
      on the virtual address range "A(range)" shown in the picture.

    sys_madvise
      // Acquire the semaphore in shared mode.
      down_read(&current->mm->mmap_sem)
      ...
      madvise_vma
        switch (behavior)
        case MADV_DONTNEED:
             madvise_dontneed
               zap_page_range
                 unmap_vmas
                   unmap_page_range
                     zap_pud_range
                       zap_pmd_range
                         //
                         // Assume that this huge page has never been accessed.
                         // I.e. content of the PMD entry is zero (not mapped).
                         //
                         if (pmd_trans_huge(*pmd)) {
                             // We don't get here due to the above assumption.
                         }
                         //
                         // Assume that Thread B incurred a page fault and
             .---------> // sneaks in here as shown below.
             |           //
             |           if (pmd_none_or_clear_bad(pmd))
             |               {
             |                 if (unlikely(pmd_bad(*pmd)))
             |                     pmd_clear_bad
             |                     {
             |                       pmd_ERROR
             |                         // Log "bad pmd ..." message here.
             |                       pmd_clear
             |                         // Clear the page's PMD entry.
             |                         // Thread B incremented the map count
             |                         // in page_add_new_anon_rmap(), but
             |                         // now the page is no longer mapped
             |                         // by a PMD entry (-> inconsistency).
             |                     }
             |               }
             |
             v
    - Thread B is handling a page fault on virtual address "B(fault)" shown
      in the picture.

    ...
    do_page_fault
      __do_page_fault
        // Acquire the semaphore in shared mode.
        down_read_trylock(&mm->mmap_sem)
        ...
        handle_mm_fault
          if (pmd_none(*pmd) && transparent_hugepage_enabled(vma))
              // We get here due to the above assumption (PMD entry is zero).
              do_huge_pmd_anonymous_page
                alloc_hugepage_vma
                  // Allocate a new transparent huge page here.
                ...
                __do_huge_pmd_anonymous_page
                  ...
                  spin_lock(&mm->page_table_lock)
                  ...
                  page_add_new_anon_rmap
                    // Here we increment the page's map count (starts at -1).
                    atomic_set(&page->_mapcount, 0)
                  set_pmd_at
                    // Here we set the page's PMD entry which will be cleared
                    // when Thread A calls pmd_clear_bad().
                  ...
                  spin_unlock(&mm->page_table_lock)

    The mmap_sem does not prevent the race because both threads are acquiring
    it in shared mode (down_read).  Thread B holds the page_table_lock while
    the page's map count and PMD table entry are updated.  However, Thread A
    does not synchronize on that lock.

====== end quote =======

[akpm@linux-foundation.org: checkpatch fixes]
Reported-by: Ulrich Obergfell <uobergfe@redhat.com>
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: Dave Jones <davej@redhat.com>
Acked-by: Larry Woodman <lwoodman@redhat.com>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: <stable@vger.kernel.org>		[2.6.38+]
Cc: Mark Salter <msalter@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-21 17:54:54 -07:00
Linus Torvalds 30d73f3752 dlm for 3.4
This set includes one trivial fix, and one simple recovery
 speed up.  Directory recovery can use the standard hash table
 to find resources rather than always searching the linear
 recovery list.
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Merge tag 'dlm-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/teigland/linux-dlm

Pull dlm updates for 3.4 from David Teigland:
 "This set includes one trivial fix, and one simple recovery speed up.
  Directory recovery can use the standard hash table to find resources
  rather than always searching the linear recovery list."

* tag 'dlm-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/teigland/linux-dlm:
  dlm: last element of dlm_local_addr[] never used
  dlm: fix slow rsb search in dir recovery
2012-03-21 13:54:22 -07:00
Linus Torvalds e2a0883e40 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs pile 1 from Al Viro:
 "This is _not_ all; in particular, Miklos' and Jan's stuff is not there
  yet."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (64 commits)
  ext4: initialization of ext4_li_mtx needs to be done earlier
  debugfs-related mode_t whack-a-mole
  hfsplus: add an ioctl to bless files
  hfsplus: change finder_info to u32
  hfsplus: initialise userflags
  qnx4: new helper - try_extent()
  qnx4: get rid of qnx4_bread/qnx4_getblk
  take removal of PF_FORKNOEXEC to flush_old_exec()
  trim includes in inode.c
  um: uml_dup_mmap() relies on ->mmap_sem being held, but activate_mm() doesn't hold it
  um: embed ->stub_pages[] into mmu_context
  gadgetfs: list_for_each_safe() misuse
  ocfs2: fix leaks on failure exits in module_init
  ecryptfs: make register_filesystem() the last potential failure exit
  ntfs: forgets to unregister sysctls on register_filesystem() failure
  logfs: missing cleanup on register_filesystem() failure
  jfs: mising cleanup on register_filesystem() failure
  make configfs_pin_fs() return root dentry on success
  configfs: configfs_create_dir() has parent dentry in dentry->d_parent
  configfs: sanitize configfs_create()
  ...
2012-03-21 13:36:41 -07:00
Linus Torvalds 3556485f15 Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security subsystem updates for 3.4 from James Morris:
 "The main addition here is the new Yama security module from Kees Cook,
  which was discussed at the Linux Security Summit last year.  Its
  purpose is to collect miscellaneous DAC security enhancements in one
  place.  This also marks a departure in policy for LSM modules, which
  were previously limited to being standalone access control systems.
  Chromium OS is using Yama, and I believe there are plans for Ubuntu,
  at least.

  This patchset also includes maintenance updates for AppArmor, TOMOYO
  and others."

Fix trivial conflict in <net/sock.h> due to the jumo_label->static_key
rename.

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (38 commits)
  AppArmor: Fix location of const qualifier on generated string tables
  TOMOYO: Return error if fails to delete a domain
  AppArmor: add const qualifiers to string arrays
  AppArmor: Add ability to load extended policy
  TOMOYO: Return appropriate value to poll().
  AppArmor: Move path failure information into aa_get_name and rename
  AppArmor: Update dfa matching routines.
  AppArmor: Minor cleanup of d_namespace_path to consolidate error handling
  AppArmor: Retrieve the dentry_path for error reporting when path lookup fails
  AppArmor: Add const qualifiers to generated string tables
  AppArmor: Fix oops in policy unpack auditing
  AppArmor: Fix error returned when a path lookup is disconnected
  KEYS: testing wrong bit for KEY_FLAG_REVOKED
  TOMOYO: Fix mount flags checking order.
  security: fix ima kconfig warning
  AppArmor: Fix the error case for chroot relative path name lookup
  AppArmor: fix mapping of META_READ to audit and quiet flags
  AppArmor: Fix underflow in xindex calculation
  AppArmor: Fix dropping of allowed operations that are force audited
  AppArmor: Add mising end of structure test to caps unpacking
  ...
2012-03-21 13:25:04 -07:00
Linus Torvalds c7c66c0cb0 Power management updates for 3.4
Assorted extensions and fixes including:
 
 * Introduction of early/late suspend/hibernation device callbacks.
 * Generic PM domains extensions and fixes.
 * devfreq updates from Axel Lin and MyungJoo Ham.
 * Device PM QoS updates.
 * Fixes of concurrency problems with wakeup sources.
 * System suspend and hibernation fixes.
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Merge tag 'pm-for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management updates for 3.4 from Rafael Wysocki:
 "Assorted extensions and fixes including:

  * Introduction of early/late suspend/hibernation device callbacks.
  * Generic PM domains extensions and fixes.
  * devfreq updates from Axel Lin and MyungJoo Ham.
  * Device PM QoS updates.
  * Fixes of concurrency problems with wakeup sources.
  * System suspend and hibernation fixes."

* tag 'pm-for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (43 commits)
  PM / Domains: Check domain status during hibernation restore of devices
  PM / devfreq: add relation of recommended frequency.
  PM / shmobile: Make MTU2 driver use pm_genpd_dev_always_on()
  PM / shmobile: Make CMT driver use pm_genpd_dev_always_on()
  PM / shmobile: Make TMU driver use pm_genpd_dev_always_on()
  PM / Domains: Introduce "always on" device flag
  PM / Domains: Fix hibernation restore of devices, v2
  PM / Domains: Fix handling of wakeup devices during system resume
  sh_mmcif / PM: Use PM QoS latency constraint
  tmio_mmc / PM: Use PM QoS latency constraint
  PM / QoS: Make it possible to expose PM QoS latency constraints
  PM / Sleep: JBD and JBD2 missing set_freezable()
  PM / Domains: Fix include for PM_GENERIC_DOMAINS=n case
  PM / Freezer: Remove references to TIF_FREEZE in comments
  PM / Sleep: Add more wakeup source initialization routines
  PM / Hibernate: Enable usermodehelpers in hibernate() error path
  PM / Sleep: Make __pm_stay_awake() delete wakeup source timers
  PM / Sleep: Fix race conditions related to wakeup source timer function
  PM / Sleep: Fix possible infinite loop during wakeup source destruction
  PM / Hibernate: print physical addresses consistently with other parts of kernel
  ...
2012-03-21 10:15:51 -07:00
Jeff Layton 3dd933061d cifs: clean up ordering in exit_cifs
...ensure that we undo things in the reverse order from the way they
were done. In truth, the ordering doesn't matter for a lot of these,
but it's still better to do it that way to be sure.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2012-03-21 11:55:48 -05:00
Jeff Layton 815465c4d7 cifs: clean up call to cifs_dfs_release_automount_timer()
Take the #ifdef junk out of the code, and turn it into a noop macro
when CONFIG_CIFS_DFS_UPCALL isn't defined.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2012-03-21 11:55:44 -05:00
Linus Torvalds 9f3938346a Merge branch 'kmap_atomic' of git://github.com/congwang/linux
Pull kmap_atomic cleanup from Cong Wang.

It's been in -next for a long time, and it gets rid of the (no longer
used) second argument to k[un]map_atomic().

Fix up a few trivial conflicts in various drivers, and do an "evil
merge" to catch some new uses that have come in since Cong's tree.

* 'kmap_atomic' of git://github.com/congwang/linux: (59 commits)
  feature-removal-schedule.txt: schedule the deprecated form of kmap_atomic() for removal
  highmem: kill all __kmap_atomic() [swarren@nvidia.com: highmem: Fix ARM build break due to __kmap_atomic rename]
  drbd: remove the second argument of k[un]map_atomic()
  zcache: remove the second argument of k[un]map_atomic()
  gma500: remove the second argument of k[un]map_atomic()
  dm: remove the second argument of k[un]map_atomic()
  tomoyo: remove the second argument of k[un]map_atomic()
  sunrpc: remove the second argument of k[un]map_atomic()
  rds: remove the second argument of k[un]map_atomic()
  net: remove the second argument of k[un]map_atomic()
  mm: remove the second argument of k[un]map_atomic()
  lib: remove the second argument of k[un]map_atomic()
  power: remove the second argument of k[un]map_atomic()
  kdb: remove the second argument of k[un]map_atomic()
  udf: remove the second argument of k[un]map_atomic()
  ubifs: remove the second argument of k[un]map_atomic()
  squashfs: remove the second argument of k[un]map_atomic()
  reiserfs: remove the second argument of k[un]map_atomic()
  ocfs2: remove the second argument of k[un]map_atomic()
  ntfs: remove the second argument of k[un]map_atomic()
  ...
2012-03-21 09:40:26 -07:00
Pavel Shilovsky 6dae51a585 CIFS: Delete echo_retries module parm
It's the essential step before respecting MaxMpxCount value during
negotiating because we will keep only one extra slot for sending
echo requests. If there is no response during two echo intervals -
reconnect the tcp session.

Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2012-03-21 11:35:38 -05:00
Pavel Shilovsky bc205ed19b CIFS: Prepare credits code for a slot reservation
that is essential for CIFS/SMB/SMB2 oplock breaks and SMB2 echos.

Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2012-03-21 11:35:36 -05:00
Pavel Shilovsky 5bc594982f CIFS: Make wait_for_free_request killable
to let us kill the proccess if it hangs waiting for a credit when
the session is down and echo is disabled.

Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2012-03-21 11:35:32 -05:00
Pavel Shilovsky 2d86dbc970 CIFS: Introduce credit-based flow control
and send no more than credits value requests at once. For SMB/CIFS
it's trivial: increment this value by receiving any message and
decrement by sending one.

Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2012-03-21 11:35:03 -05:00
Pavel Shilovsky fc40f9cf82 CIFS: Simplify inFlight logic
by making it as unsigned integer and surround access with req_lock
from server structure.

Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2012-03-21 11:27:35 -05:00
Jeff Layton 1daaae8fa4 cifs: fix issue mounting of DFS ROOT when redirecting from one domain controller to the next
This patch fixes an issue when cifs_mount receives a
STATUS_BAD_NETWORK_NAME error during cifs_get_tcon but is able to
continue after an DFS ROOT referral. In this case, the return code
variable is not reset prior to trying to mount from the system referred
to. Thus, is_path_accessible is not executed and the final DFS referral
is not performed causing a mount error.

Use case: In DNS, example.com  resolves to the secondary AD server
ad2.example.com Our primary domain controller is ad1.example.com and has
a DFS redirection set up from \\ad1\share\Users to \\files\share\Users.
Mounting \\example.com\share\Users fails.

Regression introduced by commit 724d9f1.

Cc: stable@vger.kernel.org
Reviewed-by: Pavel Shilovsky <piastry@etersoft.ru
Signed-off-by: Thomas Hadig <thomas@intapp.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2012-03-21 11:26:14 -05:00
Vivek Trivedi 5a7c9eec9f NFS: fix sb->s_id in nfs debug prints
NFS bdi flush thread in ps output is printed like "flush-<major number
in decimal>:<minor number in decimal>"
For example:
$ ps aux | grep flush
 2079 root         0 SW   [flush-0:18]
                                 ^^^^

nfs_bdi_register()
==> bdi_register_dev()
==> bdi_register(bdi, NULL, "%u:%u", MAJOR(dev), MINOR(dev));
                             ^^^^^

However, NFS sb->s_id store major:minor number in hex:

nfs_initialise_sb()
==>         snprintf(sb->s_id, sizeof(sb->s_id),
                 "%x:%x", MAJOR(sb->s_dev), MINOR(sb->s_dev));
                  ^^^^^

If we enable nfs debug prints using command:
$ rpcdebug -m nfs -s all

write to a file:
$ dd if=/dev/zero of=<NFS Mount>/testfile.txt bs=32768 count=1

Without Patch:
[ 2431.032000] NFS:     0 initiated write call (req 0:12/40, 32768 bytes
@ offset 0)                                         ^^^^

With Patch:
[ 2431.032000] NFS:     0 initiated write call (req 0:18/40, 32768 bytes
@ offset 0)                                         ^^^^

We should store NFS "s->s_id" in decimal to avoid confusion between NFS
flush thread name(in ps output) and NFS debug prints.

Signed-off-by: Vivek Trivedi <vtrivedi018@gmail.com>
Signed-off-by: Namjae Jeon <linkinjeon@gmail.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-03-21 11:45:28 -04:00
David Teigland 1b189b8889 dlm: last element of dlm_local_addr[] never used
The last element of dlm_local_addr[DLM_MAX_ADDR_COUNT]
was not used because the loop ended at COUNT - 1.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2012-03-21 09:18:34 -05:00
Sachin Bhamare 18d98f6c04 pnfs-obj: autologin: Add support for protocol autologin
The pnfs-objects protocol mandates that we autologin into devices not
present in the system, according to information specified in the
get_device_info returned from the server.

The Protocol specifies two login hints.
1. An IP address:port combination
2. A string URI which is constructed as a URL with a protocol prefix
   followed by :// and a string as address. For each  protocol prefix
   the string-address format might be different.

We only support the second option. The first option is just redundant
to the second one.
NOTE: The Kernel part of autologin does not parse the URI string. It
just channels it to a user-mode script. So any new login protocols should
only update the user-mode script which is a part of the nfs-utils package,
but the Kernel need not change.

We implement the autologin by using the call_usermodehelper() API.
(Thanks to Steve Dickson <steved@redhat.com> for pointing it out)
So there is no running daemon needed, and/or special setup.

We Add the osd_login_prog Kernel module parameters which defaults to:
	/sbin/osd_login

Kernel try's to upcall the program specified in osd_login_prog. If the file is
not found or the execution fails Kernel will disable any farther upcalls, by
zeroing out  osd_login_prog, Until Admin re-enables it by setting the
osd_login_prog parameter to a proper program.

Also add text about the osd_login program command line API to:
	Documentation/filesystems/nfs/pnfs.txt
and documentation of the new  osd_login_prog  module parameter to:
	Documentation/kernel-parameters.txt

TODO: Add timeout option in the case osd_login program gets
              stuck

Signed-off-by: Sachin Bhamare <sbhamare@panasas.com>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-03-21 09:31:47 -04:00
Bryan Schumaker c6bfa1a163 NFS: Remove nfs4_setup_sequence from generic rename code
This is an NFS v4 specific operation, so it belongs in the NFS v4 code
and not the generic client.

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-03-21 09:31:46 -04:00
Bryan Schumaker 34e137cc7e NFS: Remove nfs4_setup_sequence from generic unlink code
This is an NFS v4 specific operation, so it belongs in the NFS v4 code
and not the generic client.

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-03-21 09:31:46 -04:00
Bryan Schumaker ea7c330362 NFS: Remove nfs4_setup_sequence from generic read code
This is an NFS v4 specific operation, so it belongs in the NFS v4 code
and not the generic client.

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-03-21 09:31:45 -04:00
Bryan Schumaker c6cb80d00b NFS: Remove nfs4_setup_sequence from generic write code
This is an NFS v4 specific operation, so it belongs in the NFS v4 code
and not the generic client.

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-03-21 09:31:45 -04:00
Trond Myklebust 6f00866ddd NFS: Fix more NFS debug related build warnings
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-03-21 09:31:44 -04:00
Trond Myklebust ffa94db604 SUNRPC/LOCKD: Fix build warnings when CONFIG_SUNRPC_DEBUG is undefined
Stephen Rothwell reports:
net/sunrpc/rpcb_clnt.c: In function 'rpcb_enc_mapping':
net/sunrpc/rpcb_clnt.c:820:19: warning: unused variable 'task' [-Wunused-variable]
net/sunrpc/rpcb_clnt.c: In function 'rpcb_dec_getport':
net/sunrpc/rpcb_clnt.c:837:19: warning: unused variable 'task' [-Wunused-variable]
net/sunrpc/rpcb_clnt.c: In function 'rpcb_dec_set':
net/sunrpc/rpcb_clnt.c:860:19: warning: unused variable 'task' [-Wunused-variable]
net/sunrpc/rpcb_clnt.c: In function 'rpcb_enc_getaddr':
net/sunrpc/rpcb_clnt.c:892:19: warning: unused variable 'task' [-Wunused-variable]
net/sunrpc/rpcb_clnt.c: In function 'rpcb_dec_getaddr':
net/sunrpc/rpcb_clnt.c:914:19: warning: unused variable 'task' [-Wunused-variable]
fs/lockd/svclock.c:49:20: warning: 'nlmdbg_cookie2a' declared 'static' but never defined [-Wunused-function]

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-03-21 09:31:44 -04:00
Jan Kara 697e6fed9f writeback: Remove outdated comment
The comment is hopelessly outdated and misplaced. We no longer have 'bdi'
part of writeback work, the comment about blockdev super is outdated,
comment about throttling as well. Information about list handling is in
more detail at queue_io(). So just move the bit about older_than_this to
close to move_expired_inodes() and remove the rest.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
2012-03-21 15:27:08 +08:00
Jan Kara f469ec9c5b fs: Remove bogus wait in write_inode_now()
inode_sync_wait() in write_inode_now() is just bogus. That function waits for
I_SYNC bit to be cleared but writeback_single_inode() clears the bit on return
so the wait is effectivelly a nop unless someone else submits the inode for
writeback again. All the waiting write_inode_now() needs is achieved by using
WB_SYNC_ALL writeback mode.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
2012-03-21 15:26:47 +08:00
Linus Torvalds 69a7aebcf0 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
Pull trivial tree from Jiri Kosina:
 "It's indeed trivial -- mostly documentation updates and a bunch of
  typo fixes from Masanari.

  There are also several linux/version.h include removals from Jesper."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (101 commits)
  kcore: fix spelling in read_kcore() comment
  constify struct pci_dev * in obvious cases
  Revert "char: Fix typo in viotape.c"
  init: fix wording error in mm_init comment
  usb: gadget: Kconfig: fix typo for 'different'
  Revert "power, max8998: Include linux/module.h just once in drivers/power/max8998_charger.c"
  writeback: fix fn name in writeback_inodes_sb_nr_if_idle() comment header
  writeback: fix typo in the writeback_control comment
  Documentation: Fix multiple typo in Documentation
  tpm_tis: fix tis_lock with respect to RCU
  Revert "media: Fix typo in mixer_drv.c and hdmi_drv.c"
  Doc: Update numastat.txt
  qla4xxx: Add missing spaces to error messages
  compiler.h: Fix typo
  security: struct security_operations kerneldoc fix
  Documentation: broken URL in libata.tmpl
  Documentation: broken URL in filesystems.tmpl
  mtd: simplify return logic in do_map_probe()
  mm: fix comment typo of truncate_inode_pages_range
  power: bq27x00: Fix typos in comment
  ...
2012-03-20 21:12:50 -07:00
Linus Torvalds 3b59bf0816 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking merge from David Miller:
 "1) Move ixgbe driver over to purely page based buffering on receive.
     From Alexander Duyck.

  2) Add receive packet steering support to e1000e, from Bruce Allan.

  3) Convert TCP MD5 support over to RCU, from Eric Dumazet.

  4) Reduce cpu usage in handling out-of-order TCP packets on modern
     systems, also from Eric Dumazet.

  5) Support the IP{,V6}_UNICAST_IF socket options, making the wine
     folks happy, from Erich Hoover.

  6) Support VLAN trunking from guests in hyperv driver, from Haiyang
     Zhang.

  7) Support byte-queue-limtis in r8169, from Igor Maravic.

  8) Outline code intended for IP_RECVTOS in IP_PKTOPTIONS existed but
     was never properly implemented, Jiri Benc fixed that.

  9) 64-bit statistics support in r8169 and 8139too, from Junchang Wang.

  10) Support kernel side dump filtering by ctmark in netfilter
      ctnetlink, from Pablo Neira Ayuso.

  11) Support byte-queue-limits in gianfar driver, from Paul Gortmaker.

  12) Add new peek socket options to assist with socket migration, from
      Pavel Emelyanov.

  13) Add sch_plug packet scheduler whose queue is controlled by
      userland daemons using explicit freeze and release commands.  From
      Shriram Rajagopalan.

  14) Fix FCOE checksum offload handling on transmit, from Yi Zou."

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1846 commits)
  Fix pppol2tp getsockname()
  Remove printk from rds_sendmsg
  ipv6: fix incorrent ipv6 ipsec packet fragment
  cpsw: Hook up default ndo_change_mtu.
  net: qmi_wwan: fix build error due to cdc-wdm dependecy
  netdev: driver: ethernet: Add TI CPSW driver
  netdev: driver: ethernet: add cpsw address lookup engine support
  phy: add am79c874 PHY support
  mlx4_core: fix race on comm channel
  bonding: send igmp report for its master
  fs_enet: Add MPC5125 FEC support and PHY interface selection
  net: bpf_jit: fix BPF_S_LDX_B_MSH compilation
  net: update the usage of CHECKSUM_UNNECESSARY
  fcoe: use CHECKSUM_UNNECESSARY instead of CHECKSUM_PARTIAL on tx
  net: do not do gso for CHECKSUM_UNNECESSARY in netif_needs_gso
  ixgbe: Fix issues with SR-IOV loopback when flow control is disabled
  net/hyperv: Fix the code handling tx busy
  ixgbe: fix namespace issues when FCoE/DCB is not enabled
  rtlwifi: Remove unused ETH_ADDR_LEN defines
  igbvf: Use ETH_ALEN
  ...

Fix up fairly trivial conflicts in drivers/isdn/gigaset/interface.c and
drivers/net/usb/{Kconfig,qmi_wwan.c} as per David.
2012-03-20 21:04:47 -07:00