virtio: balloon: Add freeze, restore handlers to support S4

Handling balloon hibernate / restore is tricky.  If the balloon was
inflated before going into the hibernation state, upon resume, the host
will not have any memory of that.  Any pages that were passed on to the
host earlier would most likely be invalid, and the host will have to
re-balloon to the previous value to get in the pre-hibernate state.

So the only sane thing for the guest to do here is to discard all the
pages that were put in the balloon.  When to discard the pages is the
next question.

One solution is to deflate the balloon just before writing the image to
the disk (in the freeze() PM callback).  However, asking for pages from
the host just to discard them immediately after seems wasteful of
resources.  Hence, it makes sense to do this by just fudging our
counters soon after wakeup.  This means we don't deflate the balloon
before sleep, and also don't put unnecessary pressure on the host.

This also helps in the thaw case: if the freeze fails for whatever
reason, the balloon should continue to remain in the inflated state.
This was tested by issuing 'swapoff -a' and trying to go into the S4
state.  That fails, and the balloon stays inflated, as expected.  Both
the host and the guest are happy.

Finally, in the restore() callback, we empty the list of pages that were
previously given off to the host, add the appropriate number of pages to
the totalram_pages counter, reset the num_pages counter to 0, and
all is fine.

As a last step, delete the vqs on the freeze callback to prepare for
hibernation, and re-create them in the restore and thaw callbacks to
resume normal operation.

The kthread doesn't race with any operations here, since it's frozen
before the freeze() call and is thawed after the thaw() and restore()
callbacks, so we're safe with that.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

virtio: balloon: Move vq initialization into separate function

The probe and PM restore functions will share this code.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

virtio: net: Add freeze, restore handlers to support S4

Remove all the vqs, disable napi and detach from the netdev on
hibernation.

Re-create vqs after restoring from a hibernated image, re-enable napi
and re-attach the netdev.  This keeps networking working across
hibernation.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

virtio: net: Move vq and vq buf removal into separate function

The remove and PM freeze functions will share this code.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

virtio: net: Move vq initialization into separate function

The probe and PM restore functions will share this code.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

virtio: blk: Add freeze, restore handlers to support S4

Delete the vq and flush any pending requests from the block queue on the
freeze callback to prepare for hibernation.

Re-create the vq in the restore callback to resume normal function.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

virtio: blk: Move vq initialization to separate function

The probe and PM restore functions will share this code.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

virtio: console: Disable callbacks for virtqueues at start of S4 freeze

To ensure we don't receive any more interrupts from the host after we
enter the freeze function, disable all vq interrupts.

There wasn't any problem seen due to this in tests, but applying this
patch makes the freeze case more robust.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

virtio: console: Add freeze and restore handlers to support S4

Remove all vqs and associated buffers in the freeze callback which
prepares us to go into hibernation state.  On restore, re-create all the
vqs and populate the input vqs with buffers to get to the pre-hibernate
state.

Note: Any outstanding unconsumed buffers are discarded; which means
there's a possibility of data loss in case the host or the guest didn't
consume any data already present in the vqs.  This can be addressed in a
later patch series, perhaps in virtio common code.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

virtio: console: Move vq and vq buf removal into separate functions

This common code will be shared with the PM freeze function.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

virtio: pci: add PM notification handlers for restore, freeze, thaw, poweroff

Handle thaw, restore and freeze notifications from the PM core.  Expose
these to individual virtio drivers that can quiesce and resume vq
operations.  For drivers not implementing the thaw() method, use the
restore method instead.

These functions also save device-specific data so that the device can be
put in pre-suspend state after resume, and disable and enable the PCI
device in the freeze and resume functions, respectively.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

virtio: pci: switch to new PM API

The older PM API doesn't have a way to get notifications on hibernate
events.  Switch to the newer one that gives us those notifications.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

virtio_blk: fix config handler race

Fix a theoretical race related to config work
handler: a config interrupt might happen
after we flush config work but before we
reset the device. It will then cause the
config work to run during or after reset.

Two problems with this:
- if this runs after device is gone we will get use after free
- access of config while reset is in progress is racy
(as layout is changing).

As a solution
1. flush after reset when we know there will be no more interrupts
2. add a flag to disable config access before reset

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

virtio: add debugging if driver doesn't kick.

Under the existing #ifdef DEBUG, check that they don't have more than
1/10 of a second between an add_buf() and a
virtqueue_notify()/virtqueue_kick_prepare() call.

We could get false positives on a really busy system, but good for
development.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

virtio: expose added descriptors immediately.

A virtio driver does virtqueue_add_buf() multiple times before finally
calling virtqueue_kick(); previously we only exposed the added buffers
in the virtqueue_kick() call.  This means we don't need a memory
barrier in virtqueue_add_buf(), but it reduces concurrency as the
device (ie. host) can't see the buffers until the kick.

In the unusual (but now possible) case where a driver does add_buf()
and get_buf() without doing a kick, we do need to insert one before
our counter wraps.  Otherwise we could wrap num_added, and later on
not realize that we have passed the marker where we should have
kicked.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

virtio: avoid modulus operation.

Since we know vq->vring.num is a power of 2, modulus is lazy (it's asserted
in vring_new_virtqueue()).

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

virtio: support unlocked queue kick

Based on patch by Christoph for virtio_blk speedup:

Split virtqueue_kick to be able to do the actual notification
outside the lock protecting the virtqueue.  This patch was
originally done by Stefan Hajnoczi, but I can't find the
original one anymore and had to recreated it from memory.
Pointers to the original or corrections for the commit message
are welcome.

Stefan's patch was here:

https://github.com/stefanha/linux/commit/a6d06644e3a58e57a774e77d7dc34c4a5a2e7496
http://www.spinics.net/lists/linux-virtualization/msg14616.html

Third time's the charm!

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

virtio: rename virtqueue_add_buf_gfp to virtqueue_add_buf

Remove wrapper functions. This makes the allocation type explicit in
all callers; I used GPF_KERNEL where it seemed obvious, left it at
GFP_ATOMIC otherwise.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Reviewed-by: Christoph Hellwig <hch@lst.de>

virtio: document functions better.

The old documentation is left over from when we used a structure with
strategy pointers.

And move the documentation to the C file as per kernel practice.
Though I disagree...

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Reviewed-by: Christoph Hellwig <hch@lst.de>

virtio-balloon: Trivial cleanups

Trivial changes to remove forgotten junk, format comments, and correct names.

Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: virtualization@lists.linux-foundation.org
Signed-off-by: Sasha Levin <levinsasha928@gmail.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

virtio: harsher barriers for rpmsg.

We were cheating with our barriers; using the smp ones rather than the
real device ones.  That was fine, until rpmsg came along, which is
used to talk to a real device (a non-SMP CPU).

Unfortunately, just putting back the real barriers (reverting
d57ed95d) causes a performance regression on virtio-pci.  In
particular, Amos reports netbench's TCP_RR over virtio_net CPU
utilization increased up to 35% while throughput went down by up to
14%.

By comparison, this branch is in the noise.

Reference: https://lkml.org/lkml/2011/12/11/22

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

Merge tag 'for-linus' of git://git./linux/kernel/git/mst/vhost

lib: use generic pci_iomap on all architectures

Many architectures don't want to pull in iomap.c,
so they ended up duplicating pci_iomap from that file.
That function isn't trivial, and we are going to modify it
https://lkml.org/lkml/2011/11/14/183
so the duplication hurts.

This reduces the scope of the problem significantly,
by moving pci_iomap to a separate file and
referencing that from all architectures.

* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  alpha: drop pci_iomap/pci_iounmap from pci-noop.c
  mn10300: switch to GENERIC_PCI_IOMAP
  mn10300: add missing __iomap markers
  frv: switch to GENERIC_PCI_IOMAP
  tile: switch to GENERIC_PCI_IOMAP
  tile: don't panic on iomap
  sparc: switch to GENERIC_PCI_IOMAP
  sh: switch to GENERIC_PCI_IOMAP
  powerpc: switch to GENERIC_PCI_IOMAP
  parisc: switch to GENERIC_PCI_IOMAP
  mips: switch to GENERIC_PCI_IOMAP
  microblaze: switch to GENERIC_PCI_IOMAP
  arm: switch to GENERIC_PCI_IOMAP
  alpha: switch to GENERIC_PCI_IOMAP
  lib: add GENERIC_PCI_IOMAP
  lib: move GENERIC_IOMAP to lib/Kconfig

Fix up trivial conflicts due to changes nearby in arch/{m68k,score}/Kconfig

Merge tag 'for-linux-3.3-merge-window' of git://linux-c6x.org/git/projects/linux-c6x-upstreaming

* tag 'for-linux-3.3-merge-window' of git://linux-c6x.org/git/projects/linux-c6x-upstreaming: (29 commits)
  C6X: replace tick_nohz_stop/restart_sched_tick calls
  C6X: add register_cpu call
  C6X: deal with memblock API changes
  C6X: fix timer64 initialization
  C6X: fix layout of EMIFA registers
  C6X: MAINTAINERS
  C6X: DSCR - Device State Configuration Registers
  C6X: EMIF - External Memory Interface
  C6X: general SoC support
  C6X: library code
  C6X: headers
  C6X: ptrace support
  C6X: loadable module support
  C6X: cache control
  C6X: clocks
  C6X: build infrastructure
  C6X: syscalls
  C6X: interrupt handling
  C6X: time management
  C6X: signal management
  ...

Merge branch 'next' of git://git.monstr.eu/linux-2.6-microblaze

* 'next' of git://git.monstr.eu/linux-2.6-microblaze:
  microblaze: Wire-up new system calls
  microblaze: Remove NO_IRQ from architecture
  input: xilinx_ps2: Don't use NO_IRQ
  block: xsysace: Don't use NO_IRQ
  microblaze: Trivial asm fix
  microblaze: Fix debug message in module
  microblaze: Remove eprintk macro
  microblaze: Send CR before LF for early console
  microblaze: Change NO_IRQ to 0
  microblaze: Use irq_of_parse_and_map for timer
  microblaze: intc: Change variable name
  microblaze: Use of_find_compatible_node for timer and intc
  microblaze: Add __cmpdi2
  microblaze: Synchronize __pa __va macros

Merge branch 'unicore32' of git://github.com/gxt/linux

* 'unicore32' of git://github.com/gxt/linux:
  rtc-puv3: solve section mismatch in rtc-puv3.c
  rtc-puv3: using module_platform_driver()
  i2c-puv3: using module_platform_driver()
  rtc-puv3: irq: remove IRQF_DISABLED
  unicore32: Remove IRQF_DISABLED
  unicore32: Use set_current_blocked()
  unicore32: add ioremap_nocache definition
  unicore32: delete specified xlate_dev_mem_ptr
  of: add include asm/setup.h in drivers/of/fdt.c
  unicore32: standardize /proc/iomem "Kernel code" name

Merge branch 'for-linus' of git://git./linux/kernel/git/lliubbo/blackfin

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/lliubbo/blackfin:
  blackfin: bf561: add adv7183 capture support
  blackfin: bf537: add capture support
  blackfin: bf548: add capture support
  blackfin: time-ts: rm unused func broadcast_timer_setup()
  blackfin: i2c-lcd: change default clock rate
  blackfin: mac: dsa: add vlan mask in board file
  blackfin: bf537: change num_chipselect for spi-sport
  blackfin: serial: bfin-uart: remove unused field
  bf54x: get mem size: missing break in switch
  blackfin: smp: fix msg queue overflow issue
  blackfin: config: update macro SPI_BFIN in board file
  blackfin: config: update def config for all boards
  blackfin: smp: cleanup smp code
  blackfin: smp: add suspend and wakeup irq flags
  blackfin: bf533-stamp: add missed patches for new asoc driver
  blackfin: bf533-stamp: fix ad1836 name

Merge branch 'writeback-for-linus' of git://git./linux/kernel/git/wfg/linux

* 'writeback-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux:
  writeback: move MIN_WRITEBACK_PAGES to fs-writeback.c
  writeback: balanced_rate cannot exceed write bandwidth
  writeback: do strict bdi dirty_exceeded
  writeback: avoid tiny dirty poll intervals
  writeback: max, min and target dirty pause time
  writeback: dirty ratelimit - think time compensation
  btrfs: fix dirtied pages accounting on sub-page writes
  writeback: fix dirtied pages accounting on redirty
  writeback: fix dirtied pages accounting on sub-page writes
  writeback: charge leaked page dirties to active tasks
  writeback: Include all dirty inodes in background writeback

Merge branch 'akpm' (aka "Andrew's patch-bomb")

Andrew elucidates:
 - First installmeant of MM.  We have a HUGE number of MM patches this
   time.  It's crazy.
 - MAINTAINERS updates
 - backlight updates
 - leds
 - checkpatch updates
 - misc ELF stuff
 - rtc updates
 - reiserfs
 - procfs
 - some misc other bits

* akpm: (124 commits)
  user namespace: make signal.c respect user namespaces
  workqueue: make alloc_workqueue() take printf fmt and args for name
  procfs: add hidepid= and gid= mount options
  procfs: parse mount options
  procfs: introduce the /proc/<pid>/map_files/ directory
  procfs: make proc_get_link to use dentry instead of inode
  signal: add block_sigmask() for adding sigmask to current->blocked
  sparc: make SA_NOMASK a synonym of SA_NODEFER
  reiserfs: don't lock root inode searching
  reiserfs: don't lock journal_init()
  reiserfs: delay reiserfs lock until journal initialization
  reiserfs: delete comments referring to the BKL
  drivers/rtc/interface.c: fix alarm rollover when day or month is out-of-range
  drivers/rtc/rtc-twl.c: add DT support for RTC inside twl4030/twl6030
  drivers/rtc/: remove redundant spi driver bus initialization
  drivers/rtc/rtc-jz4740.c: make jz4740_rtc_driver static
  drivers/rtc/rtc-mc13xxx.c: make mc13xxx_rtc_idtable static
  rtc: convert drivers/rtc/* to use module_platform_driver()
  drivers/rtc/rtc-wm831x.c: convert to devm_kzalloc()
  drivers/rtc/rtc-wm831x.c: remove unused period IRQ handler
  ...

user namespace: make signal.c respect user namespaces

ipc/mqueue.c: for __SI_MESQ, convert the uid being sent to recipient's
user namespace. (new, thanks Oleg)

__send_signal: convert current's uid to the recipient's user namespace
for any siginfo which is not SI_FROMKERNEL (patch from Oleg, thanks
again :)

do_notify_parent and do_notify_parent_cldstop: map task's uid to parent's
user namespace

ptrace_signal maps parent's uid into current's user namespace before
including in signal to current.  IIUC Oleg has argued that this shouldn't
matter as the debugger will play with it, but it seems like not converting
the value currently being set is misleading.

Changelog:
Sep 20: Inspired by Oleg's suggestion, define map_cred_ns() helper to
simplify callers and help make clear what we are translating
        (which uid into which namespace).  Passing the target task would
make callers even easier to read, but we pass in user_ns because
current_user_ns() != task_cred_xxx(current, user_ns).
Sep 20: As recommended by Oleg, also put task_pid_vnr() under rcu_read_lock
in ptrace_signal().
Sep 23: In send_signal(), detect when (user) signal is coming from an
ancestor or unrelated user namespace.  Pass that on to __send_signal,
which sets si_uid to 0 or overflowuid if needed.
Oct 12: Base on Oleg's fixup_uid() patch.  On top of that, handle all
SI_FROMKERNEL cases at callers, because we can't assume sender is
current in those cases.
Nov 10: (mhelsley) rename fixup_uid to more meaningful usern_fixup_signal_uid
Nov 10: (akpm) make the !CONFIG_USER_NS case clearer

Signed-off-by: Serge Hallyn <serge.hallyn@canonical.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Matt Helsley <matthltc@us.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
From: Serge Hallyn <serge.hallyn@canonical.com>
Subject: __send_signal: pass q->info, not info, to userns_fixup_signal_uid (v2)

Eric Biederman pointed out that passing info is a bug and could lead to a
NULL pointer deref to boot.

A collection of signal, securebits, filecaps, cap_bounds, and a few other
ltp tests passed with this kernel.

Changelog:
    Nov 18: previous patch missed a leading '&'

Signed-off-by: Serge Hallyn <serge.hallyn@canonical.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
From: Dan Carpenter <dan.carpenter@oracle.com>
Subject: ipc/mqueue: lock() => unlock() typo

There was a double lock typo introduced in b085f4bd6b21 "user namespace:
make signal.c respect user namespaces"

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Matt Helsley <matthltc@us.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Serge Hallyn <serge@hallyn.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

workqueue: make alloc_workqueue() take printf fmt and args for name

alloc_workqueue() currently expects the passed in @name pointer to remain
accessible.  This is inconvenient and a bit silly given that the whole wq
is being dynamically allocated.  This patch updates alloc_workqueue() and
friends to take printf format string instead of opaque string and matching
varargs at the end.  The name is allocated together with the wq and
formatted.

alloc_ordered_workqueue() is converted to a macro to unify varargs
handling with alloc_workqueue(), and, while at it, add comment to
alloc_workqueue().

None of the current in-kernel users pass in string with '%' as constant
name and this change shouldn't cause any problem.

[akpm@linux-foundation.org: use __printf]
Signed-off-by: Tejun Heo <tj@kernel.org>
Suggested-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

procfs: add hidepid= and gid= mount options

Add support for mount options to restrict access to /proc/PID/
directories.  The default backward-compatible "relaxed" behaviour is left
untouched.

The first mount option is called "hidepid" and its value defines how much
info about processes we want to be available for non-owners:

hidepid=0 (default) means the old behavior - anybody may read all
world-readable /proc/PID/* files.

hidepid=1 means users may not access any /proc/<pid>/ directories, but
their own.  Sensitive files like cmdline, sched*, status are now protected
against other users.  As permission checking done in proc_pid_permission()
and files' permissions are left untouched, programs expecting specific
files' modes are not confused.

hidepid=2 means hidepid=1 plus all /proc/PID/ will be invisible to other
users.  It doesn't mean that it hides whether a process exists (it can be
learned by other means, e.g.  by kill -0 $PID), but it hides process' euid
and egid.  It compicates intruder's task of gathering info about running
processes, whether some daemon runs with elevated privileges, whether
another user runs some sensitive program, whether other users run any
program at all, etc.

gid=XXX defines a group that will be able to gather all processes' info
(as in hidepid=0 mode).  This group should be used instead of putting
nonroot user in sudoers file or something.  However, untrusted users (like
daemons, etc.) which are not supposed to monitor the tasks in the whole
system should not be added to the group.

hidepid=1 or higher is designed to restrict access to procfs files, which
might reveal some sensitive private information like precise keystrokes
timings:

http://www.openwall.com/lists/oss-security/2011/11/05/3

hidepid=1/2 doesn't break monitoring userspace tools.  ps, top, pgrep, and
conky gracefully handle EPERM/ENOENT and behave as if the current user is
the only user running processes.  pstree shows the process subtree which
contains "pstree" process.

Note: the patch doesn't deal with setuid/setgid issues of keeping
preopened descriptors of procfs files (like
https://lkml.org/lkml/2011/2/7/368).  We rely on that the leaked
information like the scheduling counters of setuid apps doesn't threaten
anybody's privacy - only the user started the setuid program may read the
counters.

Signed-off-by: Vasiliy Kulikov <segoon@openwall.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Randy Dunlap <rdunlap@xenotime.net>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Greg KH <greg@kroah.com>
Cc: Theodore Tso <tytso@MIT.EDU>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: James Morris <jmorris@namei.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

procfs: parse mount options

Add support for procfs mount options.  Actual mount options are coming in
the next patches.

Signed-off-by: Vasiliy Kulikov <segoon@openwall.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Randy Dunlap <rdunlap@xenotime.net>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Greg KH <greg@kroah.com>
Cc: Theodore Tso <tytso@MIT.EDU>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: James Morris <jmorris@namei.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

procfs: introduce the /proc/<pid>/map_files/ directory

This one behaves similarly to the /proc/<pid>/fd/ one - it contains
symlinks one for each mapping with file, the name of a symlink is
"vma->vm_start-vma->vm_end", the target is the file.  Opening a symlink
results in a file that point exactly to the same inode as them vma's one.

For example the ls -l of some arbitrary /proc/<pid>/map_files/

 | lr-x------ 1 root root 64 Aug 26 06:40 7f8f80403000-7f8f80404000 -> /lib64/libc-2.5.so
 | lr-x------ 1 root root 64 Aug 26 06:40 7f8f8061e000-7f8f80620000 -> /lib64/libselinux.so.1
 | lr-x------ 1 root root 64 Aug 26 06:40 7f8f80826000-7f8f80827000 -> /lib64/libacl.so.1.1.0
 | lr-x------ 1 root root 64 Aug 26 06:40 7f8f80a2f000-7f8f80a30000 -> /lib64/librt-2.5.so
 | lr-x------ 1 root root 64 Aug 26 06:40 7f8f80a30000-7f8f80a4c000 -> /lib64/ld-2.5.so

This *helps* checkpointing process in three ways:

1. When dumping a task mappings we do know exact file that is mapped
   by particular region.  We do this by opening
   /proc/$pid/map_files/$address symlink the way we do with file
   descriptors.

2. This also helps in determining which anonymous shared mappings are
   shared with each other by comparing the inodes of them.

3. When restoring a set of processes in case two of them has a mapping
   shared, we map the memory by the 1st one and then open its
   /proc/$pid/map_files/$address file and map it by the 2nd task.

Using /proc/$pid/maps for this is quite inconvenient since it brings
repeatable re-reading and reparsing for this text file which slows down
restore procedure significantly.  Also as being pointed in (3) it is a way
easier to use top level shared mapping in children as
/proc/$pid/map_files/$address when needed.

[akpm@linux-foundation.org: coding-style fixes]
[gorcunov@openvz.org: make map_files depend on CHECKPOINT_RESTORE]
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Reviewed-by: Vasiliy Kulikov <segoon@openwall.com>
Reviewed-by: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Tejun Heo <tj@kernel.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

procfs: make proc_get_link to use dentry instead of inode

Prepare the ground for the next "map_files" patch which needs a name of a
link file to analyse.

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Vasiliy Kulikov <segoon@openwall.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
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>

signal: add block_sigmask() for adding sigmask to current->blocked

Abstract the code sequence for adding a signal handler's sa_mask to
current->blocked because the sequence is identical for all architectures.
Furthermore, in the past some architectures actually got this code wrong,
so introduce a wrapper that all architectures can use.

Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

sparc: make SA_NOMASK a synonym of SA_NODEFER

Unlike other architectures, sparc currently has no SA_NODEFER definition
but only the older SA_NOMASK.  Since SA_NOMASK is the historical name for
SA_NODEFER, add SA_NODEFER and copy what other architectures do by making
SA_NOMASK a synonym for SA_NODEFER.

Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

reiserfs: don't lock root inode searching

Nothing requires that we lock the filesystem until the root inode is
provided.

Also iget5_locked() triggers a warning because we are holding the
filesystem lock while allocating the inode, which result in a lockdep
suspicion that we have a lock inversion against the reclaim path:

[ 1986.896979] =================================
[ 1986.896990] [ INFO: inconsistent lock state ]
[ 1986.896997] 3.1.1-main #8
[ 1986.897001] ---------------------------------
[ 1986.897007] inconsistent {RECLAIM_FS-ON-W} -> {IN-RECLAIM_FS-W} usage.
[ 1986.897016] kswapd0/16 [HC0[0]:SC0[0]:HE1:SE1] takes:
[ 1986.897023]  (&REISERFS_SB(s)->lock){+.+.?.}, at: [<c01f8bd4>] reiserfs_write_lock+0x20/0x2a
[ 1986.897044] {RECLAIM_FS-ON-W} state was registered at:
[ 1986.897050]   [<c014a5b9>] mark_held_locks+0xae/0xd0
[ 1986.897060]   [<c014aab3>] lockdep_trace_alloc+0x7d/0x91
[ 1986.897068]   [<c0190ee0>] kmem_cache_alloc+0x1a/0x93
[ 1986.897078]   [<c01e7728>] reiserfs_alloc_inode+0x13/0x3d
[ 1986.897088]   [<c01a5b06>] alloc_inode+0x14/0x5f
[ 1986.897097]   [<c01a5cb9>] iget5_locked+0x62/0x13a
[ 1986.897106]   [<c01e99e0>] reiserfs_fill_super+0x410/0x8b9
[ 1986.897114]   [<c01953da>] mount_bdev+0x10b/0x159
[ 1986.897123]   [<c01e764d>] get_super_block+0x10/0x12
[ 1986.897131]   [<c0195b38>] mount_fs+0x59/0x12d
[ 1986.897138]   [<c01a80d1>] vfs_kern_mount+0x45/0x7a
[ 1986.897147]   [<c01a83e3>] do_kern_mount+0x2f/0xb0
[ 1986.897155]   [<c01a987a>] do_mount+0x5c2/0x612
[ 1986.897163]   [<c01a9a72>] sys_mount+0x61/0x8f
[ 1986.897170]   [<c044060c>] sysenter_do_call+0x12/0x32
[ 1986.897181] irq event stamp: 7509691
[ 1986.897186] hardirqs last  enabled at (7509691): [<c0190f34>] kmem_cache_alloc+0x6e/0x93
[ 1986.897197] hardirqs last disabled at (7509690): [<c0190eea>] kmem_cache_alloc+0x24/0x93
[ 1986.897209] softirqs last  enabled at (7508896): [<c01294bd>] __do_softirq+0xee/0xfd
[ 1986.897222] softirqs last disabled at (7508859): [<c01030ed>] do_softirq+0x50/0x9d
[ 1986.897234]
[ 1986.897235] other info that might help us debug this:
[ 1986.897242]  Possible unsafe locking scenario:
[ 1986.897244]
[ 1986.897250]        CPU0
[ 1986.897254]        ----
[ 1986.897257]   lock(&REISERFS_SB(s)->lock);
[ 1986.897265] <Interrupt>
[ 1986.897269]     lock(&REISERFS_SB(s)->lock);
[ 1986.897276]
[ 1986.897277]  *** DEADLOCK ***
[ 1986.897278]
[ 1986.897286] no locks held by kswapd0/16.
[ 1986.897291]
[ 1986.897292] stack backtrace:
[ 1986.897299] Pid: 16, comm: kswapd0 Not tainted 3.1.1-main #8
[ 1986.897306] Call Trace:
[ 1986.897314]  [<c0439e76>] ? printk+0xf/0x11
[ 1986.897324]  [<c01482d1>] print_usage_bug+0x20e/0x21a
[ 1986.897332]  [<c01479b8>] ? print_irq_inversion_bug+0x172/0x172
[ 1986.897341]  [<c014855c>] mark_lock+0x27f/0x483
[ 1986.897349]  [<c0148d88>] __lock_acquire+0x628/0x1472
[ 1986.897358]  [<c0149fae>] lock_acquire+0x47/0x5e
[ 1986.897366]  [<c01f8bd4>] ? reiserfs_write_lock+0x20/0x2a
[ 1986.897384]  [<c01f8bd4>] ? reiserfs_write_lock+0x20/0x2a
[ 1986.897397]  [<c043b5ef>] mutex_lock_nested+0x35/0x26f
[ 1986.897409]  [<c01f8bd4>] ? reiserfs_write_lock+0x20/0x2a
[ 1986.897421]  [<c01f8bd4>] reiserfs_write_lock+0x20/0x2a
[ 1986.897433]  [<c01e2edd>] map_block_for_writepage+0xc9/0x590
[ 1986.897448]  [<c01b1706>] ? create_empty_buffers+0x33/0x8f
[ 1986.897461]  [<c0121124>] ? get_parent_ip+0xb/0x31
[ 1986.897472]  [<c043ef7f>] ? sub_preempt_count+0x81/0x8e
[ 1986.897485]  [<c043cae0>] ? _raw_spin_unlock+0x27/0x3d
[ 1986.897496]  [<c0121124>] ? get_parent_ip+0xb/0x31
[ 1986.897508]  [<c01e355d>] reiserfs_writepage+0x1b9/0x3e7
[ 1986.897521]  [<c0173b40>] ? clear_page_dirty_for_io+0xcb/0xde
[ 1986.897533]  [<c014a6e3>] ? trace_hardirqs_on_caller+0x108/0x138
[ 1986.897546]  [<c014a71e>] ? trace_hardirqs_on+0xb/0xd
[ 1986.897559]  [<c0177b38>] shrink_page_list+0x34f/0x5e2
[ 1986.897572]  [<c01780a7>] shrink_inactive_list+0x172/0x22c
[ 1986.897585]  [<c0178464>] shrink_zone+0x303/0x3b1
[ 1986.897597]  [<c043cae0>] ? _raw_spin_unlock+0x27/0x3d
[ 1986.897611]  [<c01788c9>] kswapd+0x3b7/0x5f2

The deadlock shouldn't happen since we are doing that allocation in the
mount path, the filesystem is not available for any reclaim.  Still the
warning is annoying.

To solve this, acquire the lock later only where we need it, right before
calling reiserfs_read_locked_inode() that wants to lock to walk the tree.

Reported-by: Knut Petersen <Knut_Petersen@t-online.de>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Jeff Mahoney <jeffm@suse.com>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

reiserfs: don't lock journal_init()

journal_init() doesn't need the lock since no operation on the filesystem
is involved there.  journal_read() and get_list_bitmap() have yet to be
reviewed carefully though before removing the lock there.  Just keep the
it around these two calls for safety.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Jeff Mahoney <jeffm@suse.com>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

reiserfs: delay reiserfs lock until journal initialization

In the mount path, transactions that are made before journal
initialization don't involve the filesystem.  We can delay the reiserfs
lock until we play with the journal.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Jeff Mahoney <jeffm@suse.com>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

reiserfs: delete comments referring to the BKL

Signed-off-by: Davidlohr Bueso <dave@gnu.org>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/interface.c: fix alarm rollover when day or month is out-of-range

Commit f44f7f96a20a ("RTC: Initialize kernel state from RTC") introduced a
potential infinite loop.  If an alarm time contains a wildcard month and
an invalid day (> 31), or a wildcard year and an invalid month (>= 12),
the loop searching for the next matching date will never terminate.  Treat
the invalid values as wildcards.

Fixes <http://bugs.debian.org/646429>, <http://bugs.debian.org/653331>

Reported-by: leo weppelman <leoweppelman@googlemail.com>
Reported-by: "P. van Gaans" <mailme667@yahoo.co.uk>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: Marcelo Roberto Jimenez <mroberto@cpti.cetuc.puc-rio.br>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Acked-by: Alessandro Zummo <a.zummo@towertech.it>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/rtc-twl.c: add DT support for RTC inside twl4030/twl6030

Add the DT support for the TI rtc-twl present in the twl4030 and twl6030
devices.

Signed-off-by: Benoit Cousson <b-cousson@ti.com>
Acked-by: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/: remove redundant spi driver bus initialization

In ancient times it was necessary to manually initialize the bus field of
an spi_driver to spi_bus_type.  These days this is done in
spi_driver_register(), so we can drop the manual assignment.

The patch was generated using the following coccinelle semantic patch:
// <smpl>
@@
identifier _driver;
@@
struct spi_driver _driver = {
.driver = {
- .bus = &spi_bus_type,
},
};
// </smpl>

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/rtc-jz4740.c: make jz4740_rtc_driver static

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/rtc-mc13xxx.c: make mc13xxx_rtc_idtable static

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

rtc: convert drivers/rtc/* to use module_platform_driver()

This patch converts the drivers in drivers/rtc/* to use the
module_platform_driver() macro which makes the code smaller and a bit
simpler.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Acked-by: Guan Xuetao <gxt@mprc.pku.edu.cn>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Haojian Zhuang <haojian.zhuang@gmail.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Srinidhi Kasagar <srinidhi.kasagar@stericsson.com>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: Ben Dooks <ben@simtec.co.uk>
Cc: John Stultz <john.stultz@linaro.org>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/rtc-wm831x.c: convert to devm_kzalloc()

Marginally less code and eliminate the possibility of memory leaks.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/rtc-wm831x.c: remove unused period IRQ handler

Due to changes in the RTC core the period interrupt is now unused so
delete the code managing it.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

rtc/ab8500: add calibration attribute to AB8500 RTC

The rtc_calibration attribute allows user-space to get and set the
AB8500's RtcCalibration register.  The AB8500 will then use the value in
this register to compensate for RTC drift every 60 seconds.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Mark Godfrey <mark.godfrey@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/rtc-ab8500.c: change msleep() to usleep_range()

The resolution of msleep is related to HZ, so with HZ set to 100 any
msleep of less than 10ms will become ~10ms.  This is not what we want.
Use the hrtimer-based usleep_range() and allow for some slack in the
non-critical path so we have more control of what is happening here.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Jonas Aaberg <jonas.aberg@stericsson.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

rtc/ab8500: set can_wake flag

Set can_wake flag so wakealarm property is visible in sysfs.

Signed-off-by: Andrew Lynn <andrew.lynn@stericsson.com>
Reviewed-by: Jonas ABERG <jonas.aberg@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

rtc/ab8500: don't disable IRQ:s when suspending

We want this driver to be able to wake up the system.

Signed-off-by: Robert Marklund <robert.marklund@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/rtc-mxc.c: make alarm work

Fix alarm IRQ handling, make the alarm one-shot.  Cleanup black magick
with a validation of already validated time data.

Add ability to wake the system with alarm.

[akpm@linux-foundation.org: fix CONFIG_PM=n build]
Signed-off-by: Yauhen Kharuzhy <jekhor@gmail.com>
Cc: Daniel Mack <daniel@caiaq.de>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/rtc-mxc.c: fix setting time for MX1 SoC

There is no way to track year in the i.MX1 RTC: Days Counter register is
9-bit wide only.  Attempt to save date after 1970-01-01 plus 512 days
causes endless loop in mxc_rtc_set_mmss().  Fix this by resetting year to
1970.

[akpm@linux-foundation.org: use conventional comment layout]
Signed-off-by: Yauhen Kharuzhy <jekhor@gmail.com>
Cc: Daniel Mack <daniel@caiaq.de>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/rtc-cmos.c: fix broken NVRAM bank 2 writing

Fix writing to NVRAM bank 2 in rtc-cmos driver.  It never worked since its
introduction in 2.6.28 because of a typo.

Signed-off-by: Ondrej Zary <linux@rainbow-software.org>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

MIPS: randomize PIE load address

... by selecting ARCH_BINFMT_ELF_RANDOMIZE_PIE

Signed-off-by: David Daney <david.daney@cavium.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs: binfmt_elf: create Kconfig variable for PIE randomization

Randomization of PIE load address is hard coded in binfmt_elf.c for X86
and ARM.  Create a new Kconfig variable
(CONFIG_ARCH_BINFMT_ELF_RANDOMIZE_PIE) for this and use it instead.  Thus
architecture specific policy is pushed out of the generic binfmt_elf.c and
into the architecture Kconfig files.

X86 and ARM Kconfigs are modified to select the new variable so there is
no change in behavior.  A follow on patch will select it for MIPS too.

Signed-off-by: David Daney <david.daney@cavium.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

crc32: optimize inner loop

Taking a pointer reference to each row in the crc table matrix, one can
reduce the inner loop with a few insn's

Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
Cc: Bob Pearson <rpearson@systemfabricworks.com>
Cc: Frank Zago <fzago@systemfabricworks.com>
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>

checkpatch: catch all occurences of type and cast spacing errors per line

Fix up type and cast spacing checks such that all occurences on a line are
examined and reported.  For example the line below has a valid cast and a
bad type, but currently we check the cast first which is good and stop:

    u16* bar = (u16 *)baz;

We will also only report one of the errors in this example:

    u16* bar = (u16*)bad;

Move to iterating across all casts and all types, reporting any failure.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Andy Whitcroft <apw@canonical.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

checkpatch: typeof may have more complex arguments

typeof may have various more complex forms as its arguement, not just an
identifier.  For now allow us to leak to the first close perenthesis ')'.

Signed-off-by: Andy Whitcroft <apw@canonical.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

checkpatch: ensure cast type is unique in the context parser

Ensure the cast type is unique in the context parser, we do not want them
to detect as a comma ','.

Signed-off-by: Andy Whitcroft <apw@canonical.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

checkpatch: fix complex macros handling of square brackets

Signed-off-by: Andy Whitcroft <apw@canonical.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

checkpatch: fix 'return is not a function' square bracket handling

We are incorrectly matching square brackets '[' and ']' leading to false
positives on more complex functions as below:

    return (dt3155_fbuffer[m]->ready_head -
dt3155_fbuffer[m]->ready_len +
dt3155_fbuffer[m]->nbuffers)%
(dt3155_fbuffer[m]->nbuffers);

Signed-off-by: Andy Whitcroft <apw@canonical.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

checkpatch: complex macro should allow the empty do while loop

It is common to stub out a function as below, this is triggering a complex
macro format incorrectly.  Sort this out:

    #define cma_early_regions_reserve(reserve)   do { } while (0)

Signed-off-by: Andy Whitcroft <apw@canonical.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

checkpatch: fix EXPORT_SYMBOL handling following a function

The following fragment defeats the DEVICE_ATTR style handing, check for
and ignore the close brace '}' in this context:

    int foo()
    {
    }
    DEVICE_ATTR(link_power_management_policy, S_IRUGO | S_IWUSR,
                ata_scsi_lpm_show, ata_scsi_lpm_put);
    EXPORT_SYMBOL_GPL(dev_attr_link_power_management_policy);

Signed-off-by: Andy Whitcroft <apw@canonical.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

checkpatch: only apply kconfig help checks for options which prompt

The intent of this check is to catch the options which the user will see
and ensure they are properly described.  It is also common for internal
only options to have a brief description.  Allow this form.

Reported-by: Steven Rostedt <rostedt@goodmis.org>
Tested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andy Whitcroft <apw@canonical.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

checkpatch: optimise statement scanner when mid-statement

In the middle of a long definition or similar, there is no possibility of
finding a smaller sub-statement.  Optimise this case by skipping statement
aquirey where there are no starts of statement (open brace '{' or
semi-colon ';').  We are likely to scan slightly more than needed still
but this is safest.

Signed-off-by: Andy Whitcroft <apw@canonical.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

checkpatch: ## is not a valid modifier

Inserting a # into the modifiers list will incorrectly add the null string
to the modifiers list, leading to an infinite loop.  As neither of these
is a valid modifier form simply ignore them.

Signed-off-by: Andy Whitcroft <apw@canonical.com>
Reported-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

checkpatch: improve memset and min/max with cast checking

Improve the checking of arguments to memset and min/max tests.

Move the checking of min/max to statement blocks instead of single line.
Change $Constant to allow any case type 0x initiator and trailing ul
specifier.  Add $FuncArg type as any function argument with or without a
cast.  Print the whole statement when showing memset or min/max messages.
Improve the memset with 0 as 3rd argument error message.

There are still weaknesses in the $FuncArg and $Constant code as arbitrary
parentheses and negative signs are not generically supported.

[akpm@linux-foundation.org: fix per Andy]
Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

checkpatch: check for common memset parameter issues against statments

Move the memset checks over to work against the statement.  Also add
checks for 0 and 1 used as lengths.  Generally these indicate badly
ordered parameters.

Signed-off-by: Andy Whitcroft <apw@canonical.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

checkpatch: correctly track the end of preprocessor commands in context

When looking for a statement we currently run on through preprocessor
commands.  This means that a header file with just definitions is parsed
over and over again combining all of the lines from the current line to
the end of file leading to severe performance issues.

Fix up context accumulation to track preprocessor commands and stop when
reaching the end of them.  At the same time vastly simplify the #define
handling.

Signed-off-by: Andy Whitcroft <apw@canonical.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

checkpatch: prefer __printf over __attribute__((format(printf,...)))

Add a warn for not using __printf.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

checkpatch: update signature "might be better as" warning

email header lines can look like signature tags.  It's valid to have
multiple email recipients on a single line but not valid to have multiple
signatures on a single line.

Validate signatures only when not in the email headers.

Clear the $in_commit_log flag when the patch filename appears.

Add '-' to the valid chars in a message header for headers
like "Message-Id:" and "In-Reply-To:".

Signed-off-by: Joe Perches <joe@perches.com>
Reported-by: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

btree: export btree_get_prev() so modules can use btree_for_each

The btree_for_each API is implemented with macros that internally call
btree_get_prev(), so if btree_get_prev() isn't exported then modules fail
to link if they try to use one of the btree_for_each macros.  Since the
rest of the btree API is exported, we should keep things orthogonal and
make this work too.

Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Steve Hodgson <steve@purestorage.com>
Acked-by: Joern Engel <joern@logfs.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

leds: convert wm8350 driver to devm_kzalloc()

Saves a small amount of code and systematically eliminates leaks.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

leds: convert wm831x status driver to devm_kzalloc()

Saves a small amount of code and systematically eliminates leaks.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/leds/leds-mc13783.c: fix off-by-one for checking num_leds

The LED id begins from 0.  Thus the maximum number of leds should be
MC13783_LED_MAX + 1.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Acked-by: Philippe Retornaz <philippe.retornaz@epfl.ch>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

leds: add driver for TCA6507 LED controller

TI's TCA6507 is the LED driver in the GTA04 Openmoko motherboard.  The
driver provides full support for brightness levels and hardware blinking.

This driver can drive each of 7 outputs as an LED or a GPIO output,
and provides hardware-assist blinking.

[akpm@linux-foundation.org: fix __mod_i2c_device_table alias]
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: NeilBrown <neilb@suse.de>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Randy Dunlap <rdunlap@xenotime.net>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/leds/leds-netxbig.c: use gpio_request_one()

Use gpio_request_one() instead of multiple gpiolib calls.  This also
simplifies error handling a bit.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Cc: Simon Guinot <sguinot@lacie.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/leds/leds-bd2802.c: use gpio_request_one()

Use gpio_request_one() instead of multiple gpiolib calls.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Cc: Kim Kyuwon <q1.kim@samsung.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/leds/leds-lp5523.c: remove unneeded forward declaration

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Cc: Samu Onkalo <samu.p.onkalo@nokia.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

leds: convert leds-dac124s085 to module_spi_driver

Factor out some boilerplate code for spi driver registration into
module_spi_driver.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Cc: Haojian Zhuang <hzhuang1@marvell.com>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Michael Hennerich <hennerich@blackfin.uclinux.org>
Cc: Mike Rapoport <mike@compulab.co.il>
Acked-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

leds: convert led i2c drivers to module_i2c_driver

Factor out some boilerplate code for i2c driver registration
into module_i2c_driver.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Cc: Haojian Zhuang <hzhuang1@marvell.com>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Michael Hennerich <hennerich@blackfin.uclinux.org>
Cc: Mike Rapoport <mike@compulab.co.il>
Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

leds: convert led platform drivers to module_platform_driver

Factor out some boilerplate code for platform driver registration into
module_platform_driver.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Acked-by: Haojian Zhuang <hzhuang1@marvell.com> [led-88pm860x.c]
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Michael Hennerich <hennerich@blackfin.uclinux.org>
Cc: Mike Rapoport <mike@compulab.co.il>
Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

backlight: convert pwm_bl to dev_pm_ops

Should be no functional changes, mainly a reorganisation to support future
work.

[akpm@linux-foundation.org: fix CONFIG_PM=n build]
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

backlight: convert platform_lcd to devm_kzalloc()

Saves some error handling code and eliminates a class of leaks.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

backlight: use kstrtoul()

The usage of simple_strtoul() or strict_strtoul() is not preferred.  Thus,
kstrtoul should be used.

This patch also fixes checkpatch error as follows:
ERROR: space required after that ',' (ctx:VxV)

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/video/backlight/ep93xx_bl.c: remove duplicated header include

module.h is included twice.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Ryan Mallon <rmallon@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

backlight/ld9040.c: regulator control in the driver

This patch supports regulator power control in the driver.  Current ld9040
driver was controlled power on/off sequence by callback function in the
board file.  But, by doing this, there's no need to register lcd power
on/off callback function in the board file.

Signed-off-by: Donghwa Lee <dh09.lee@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

backlight: convert drivers/video/backlight/* to use module_platform_driver()

Convert the drivers in drivers/video/backlight/* to use the
module_platform_driver() macro which makes the code smaller and a bit
simpler.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Acked-by: Haojian Zhuang <haojian.zhuang@gmail.com>
Acked-by: H Hartley Sweeten <hsweeten@visionengravers.com> [ep93xx_bl.c]
Cc: Mike Rapoport <mike@compulab.co.il>
Cc: Richard Purdie <rpurdie@rpsys.net>
Acked-by: Michael Hennerich <michael.hennerich@analog.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

backlight: remove ADX backlight device support

Support for the Avionic Design Xanthos backlight device got added in
commit 3b96ea9ef8 ("backlight: Add support for the Avionic Design Xanthos
backlight device.").  That support depends on ARCH_PXA_ADX.  The code that
should have provided that Kconfig symbol never got submitted.  It has
never been possible to even build this driver.  Remove it.

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Acked-by: Thierry Reding <thierry.reding@avionic-design.de>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Wim Van Sebroeck <wim@iguana.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

devfreq: add devfreq maintainer entry

As devfreq is merged at mainline. Also update the maintainer entry.

Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Kevin Hilman <khilman@ti.com>
Cc: MyungJoo Ham <myungjoo.ham@samsung.com>
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

MAINTAINERS: spi: update F: patterns

commit ca632f55669 ("spi: reorganize drivers") renamed the files, update
the F: patterns.

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

MAINTAINERS: serial:blackfin: update F: pattern

commit 0c6967b5a0 ("serial:blackfin: rename Blackfin serial driver to
bfin_uart.c") renamed the file, update the pattern.

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

MAINTAINERS: staging: media: update F: patterns

commit 4860c73804c ("staging: Move media drivers to staging/media") moved
the files, update the F: patterns.

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Mauro Carvalho Chehab<mchehab@redhat.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

MAINTAINERS: update encrypted-keys F: patterns

commit 61cf45d0199 ("encrypted-keys: create encrypted-keys directory")
moved the files, update the patterns.

Signed-off-by: Joe Perches <joe@perches.com>
Cc: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

MAINTAINERS: update greth F: patterns

commit 1fe003fd424 ("greth: Move the Aeroflex Gaisler driver") moved the
files, update the patterns.

Signed-off-by: Joe Perches <joe@perches.com>
Cc: Kristoffer Glembo <kristoffer@gaisler.com>
Cc: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

MAINTAINERS: update tulip F: patterns

commit a88394cfb58 ("ewrk3/tulip: Move the DEC - Tulip drivers") moved the
files, update the patterns.

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Grant Grundler <grundler@parisc-linux.org>
Cc: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Cc: Tobias Ringstrom <tori@unhappy.mine.nu>
Cc: Grant Grundler <grundler@parisc-linux.org>
Cc: David Davies <davies@maniac.ultranet.com>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

MAINTAINERS: update sdhci F: patterns

commit 38576af1f8c ("mmc: sdhci: make sdhci-of device drivers self
registered") moved the files around.  Update the patterns.

Signed-off-by: Joe Perches <joe@perches.com>
Cc: Shawn Guo <shawn.guo@linaro.org>
Cc: Chris Ball <cjb@laptop.org>
Acked-by: Anton Vorontsov <cbouatmailru@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

MAINTAINERS: update mfd F: patterns

commit 8959e74399c ("mfd: Delete ab3550 driver") removed the driver,
update the patterns.

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>