Use cmpxchg instead of xchg to realize this_cpu_xchg.

xchg will cause LOCK overhead since LOCK is always implied but cmpxchg
will not.

Baselines:

xchg()		= 18 cycles (no segment prefix, LOCK semantics)
__this_cpu_xchg = 1 cycle

(simulated using this_cpu_read/write, two prefixes. Looks like the
cpu can use loop optimization to get rid of most of the overhead)

Cycles before:

this_cpu_xchg	 = 37 cycles (segment prefix and LOCK (implied by xchg))

After:

this_cpu_xchg	= 11 cycle (using cmpxchg without lock semantics)
Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

Provide support as far as the hardware capabilities of the x86 cpus
allow.

Define CONFIG_CMPXCHG_LOCAL in Kconfig.cpu to allow core code to test for
fast cpuops implementations.

V1->V2:
	- Take out the definition for this_cpu_cmpxchg_8 and move it into
	  a separate patch.

tj: - Reordered ops to better follow this_cpu_* organization.
    - Renamed macro temp variables similar to their existing
      neighbours.
Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

Generic code to provide new per cpu atomic features

	this_cpu_cmpxchg
	this_cpu_xchg

Fallback occurs to functions using interrupts disable/enable
to ensure correct per cpu atomicity.

Fallback to regular cmpxchg and xchg is not possible since per cpu atomic
semantics include the guarantee that the current cpus per cpu data is
accessed atomically. Use of regular cmpxchg and xchg requires the
determination of the address of the per cpu data before regular cmpxchg
or xchg which therefore cannot be atomically included in an xchg or
cmpxchg without segment override.

tj: - Relocated new ops to conform better to the general organization.
    - This patch contains a trivial comment fix.
Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

- include/linux/percpu.h: this_cpu_add_return() and friends were
  located next to __this_cpu_add_return().  However, the overall
  organization is to first group by preemption safeness.  Relocate
  this_cpu_add_return() and friends to preemption-safe area.

- arch/x86/include/asm/percpu.h: Relocate percpu_add_return_op() after
  other more basic operations.  Relocate [__]this_cpu_add_return_8()
  so that they're first grouped by preemption safeness.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Christoph Lameter <cl@linux.com>

Supply an implementation for x86 in order to generate more efficient code.

V2->V3:
	- Cleanup
	- Remove strange type checking from percpu_add_return_op.

tj: - Dropped unused typedef from percpu_add_return_op().
    - Renamed ret__ to paro_ret__ in percpu_add_return_op().
    - Minor indentation adjustments.
Acked-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

Introduce generic support for this_cpu_add_return etc.

The fallback is to realize these operations with simpler __this_cpu_ops.

tj: - Reformatted __cpu_size_call_return2() to make it more consistent
      with its neighbors.
    - Dropped unnecessary temp variable ret__ from
      __this_cpu_generic_add_return().
Reviewed-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

* 'for-linus' of git://git.infradead.org/users/eparis/notify:
  fanotify: fill in the metadata_len field on struct fanotify_event_metadata
  fanotify: split version into version and metadata_len
  fanotify: Dont try to open a file descriptor for the overflow event
  fanotify: Introduce FAN_NOFD
  fanotify: do not leak user reference on allocation failure
  inotify: stop kernel memory leak on file creation failure
  fanotify: on group destroy allow all waiters to bypass permission check
  fanotify: Dont allow a mask of 0 if setting or removing a mark
  fanotify: correct broken ref counting in case adding a mark failed
  fanotify: if set by user unset FMODE_NONOTIFY before fsnotify_perm() is called
  fanotify: remove packed from access response message
  fanotify: deny permissions when no event was sent

* 'upstream' of git://git.linux-mips.org/pub/scm/upstream-linus: (28 commits)
  MIPS: Add a CONFIG_FORCE_MAX_ZONEORDER Kconfig option.
  MIPS: LD/SD o32 macro GAS fix update
  MIPS: Alchemy: fix build with SERIAL_8250=n
  MIPS: Rename mips_dma_cache_sync back to dma_cache_sync
  MIPS: MT: Fix typo in comment.
  SSB: Fix nvram_get on BCM47xx platform
  MIPS: BCM47xx: Swap serial console if ttyS1 was specified.
  MIPS: BCM47xx: Use sscanf for parsing mac address
  MIPS: BCM47xx: Fill values for b43 into SSB sprom
  MIPS: BCM47xx: Do not read config from CFE
  MIPS: FDT size is a be32
  MIPS: Fix CP0 COUNTER clockevent race
  MIPS: Fix regression on BCM4710 processor detection
  MIPS: JZ4740: Fix pcm device name
  MIPS: Separate two consecutive loads in memset.S
  MIPS: Send proper signal and siginfo on FP emulator faults.
  MIPS: AR7: Fix loops per jiffies on TNETD7200 devices
  MIPS: AR7: Fix double ar7_gpio_init declaration
  MIPS: Rework GENERIC_HARDIRQS Kconfig.
  MIPS: Alchemy: Add return value check for strict_strtoul()
  ...

For huge page support with base page size of 16K or 32K, we have to
increase the MAX_ORDER so that huge pages can be allocated.

[Ralf: I don't think a user should have to configure obscure constants like
this but for the time being this will have to suffice.]
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
To: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/1685/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

I am about to commit:

http://sourceware.org/ml/binutils/2010-10/msg00033.html

that fixes a problem with the LD/SD macro currently implemented by GAS for
the o32 ABI in an inconsistent way.  This is best illustrated with a
simple program, which I'm copying here from the message above for easier
reference:

$ cat ld.s
	ld	$5,32767($4)
	ld	$5,32768($4)

This gets assebled into the following output:

$ mips-linux-as -32 -mips3 -o ld.o ld.s
$ mips-linux-objdump -d ld.o

ld.o:     file format elf32-tradbigmips

Disassembly of section .text:

00000000 <.text>:
   0:	dc857fff 	ld	a1,32767(a0)
   4:	3c010001 	lui	at,0x1
   8:	00810821 	addu	at,a0,at
   c:	8c258000 	lw	a1,-32768(at)
  10:	8c268004 	lw	a2,-32764(at)
	...

Oops!

 The GAS fix makes the macro behave in a consistent way and pairs of LW/SW
instructions to be output as appropriate regardless of the size of the
offset associated with the address used.  The machine instruction is still
available, but to reach it macros have to be disabled first.  This has a
side effect of requiring the use of a machine-addressable memory operand.

 As some platforms require 64-bit operations for accesses to some I/O
registers LD/SD instructions are used in a couple of places in Linux
regardless of the ABI selected.  Here's a fix for some pieces of code
affected I've been able to track down.  The fix should be backwards
compatible with all supported binutils releases in existence and can be
used as a reference for any other places or off-tree code.  The use of the
"R" constraint guarantees a machine-addressable operand.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/1680/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

In commit 7d172bfe ("Alchemy: Add UART PM methods") I introduced
platform PM methods which call a function of the 8250 driver;
this patch works around link failures when the kernel is built
without 8250 support.
Signed-off-by: Manuel Lauss <manuel.lauss@googlemail.com>
To: Linux-MIPS <linux-mips@linux-mips.org>
Patchwork: https://patchwork.linux-mips.org/patch/1737/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

This fixes IP22 and IP28 build errors.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

The nvram_get function was never in the mainline kernel, it only existed in
an external OpenWrt patch. Use nvram_getenv function, which is in mainline
and use an include instead of an extra function declaration.  et0macaddr
contains the mac address in text from like 00:11:22:33:44:55. We have to
parse it before adding it into macaddr.

nvram_parse_macaddr will be merged into asm/mach-bcm47xx/nvram.h through
the MIPS git tree and will be available soon. It will not build now without
nvram_parse_macaddr, but it hasn't before either.
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
To: linux-mips@linux-mips.org
Cc: mb@bu3sch.de
Cc: netdev@vger.kernel.org
Cc: Hauke Mehrtens <hauke@hauke-m.de>
Acked-by: Michael Buesch <mb@bu3sch.de>
Patchwork: https://patchwork.linux-mips.org/patch/1849/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

Some devices like the Netgear WGT634U are using ttyS1 for default console
output. We should switch to that console if it was given in the kernel_args
parameters.
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
To: linux-mips@linux-mips.org
Cc: Hauke Mehrtens <hauke@hauke-m.de>
Patchwork: https://patchwork.linux-mips.org/patch/1848/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

Instead of writing own function for parsing the mac address we now
use sscanf.
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
To: linux-mips@linux-mips.org
Cc: Hauke Mehrtens <hauke@hauke-m.de>
Patchwork: https://patchwork.linux-mips.org/patch/1847/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

Fill the sprom with all available values from the nvram. Most of these
new values are needed for the b43 or b43legacy driver.

Parts of this patch have been in OpenWRT for a long time and were written
by Michael Buesch.
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
To: linux-mips@linux-mips.org
Cc: Hauke Mehrtens <hauke@hauke-m.de>
Patchwork: https://patchwork.linux-mips.org/patch/1846/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

The config options read out here are not stored in CFE but only in NVRAM on
the devices. Remove reading from CFE and only access the NVRAM.  Reading out
CFE does not harm but is useless here.
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
To: linux-mips@linux-mips.org
Cc: Hauke Mehrtens <hauke@hauke-m.de>
Patchwork: https://patchwork.linux-mips.org/patch/1845/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

The totalsize field was be32. And the reserve bootmem would cause failure.
Signed-off-by: Thomas Chou <thomas@wytron.com.tw>
To: devicetree-discuss@lists.ozlabs.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: grant.likely@secretlab.ca
Cc: David Daney <ddaney@caviumnetworks.com>
Cc: Dezhong Diao <dediao@cisco.com>
Patchwork: https://patchwork.linux-mips.org/patch/1838/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

Consider the following test case:

write_c0_compare(read_c0_count());

Even if the counter doesn't increment during execution, this might not
generate an interrupt until the counter wraps around.  The CPU may
perform the comparison each time CP0 COUNT increments, not when CP0
COMPARE is written.

If mips_next_event() is called with a very small delta, and CP0 COUNT
increments during the calculation of "cnt += delta", it is possible
that CP0 COMPARE will be written with the current value of CP0 COUNT.
If this is detected, the function should return -ETIME, to indicate
that the interrupt might not have actually gotten scheduled.
Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/1836/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

BCM4710 uses the BMIPS32 core (like BCM6345), not the MIPS 4Kc core as
was previously believed.
Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
Tested-by: Alexandros C. Couloumbis <alex@ozo.com>
Patchwork: https://patchwork.linux-mips.org/patch/1837/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

As part the ASoC multi-component patch (commit f0fba2ad) the jz4740 pcm
driver was renamed to 'jz4740-pcm-audio'. Adjust the device name
accordingly.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/1770/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

partial_fixup is used in noreorder block.

Separating two consecutive loads can save one cycle on processors with
GPR intrelock and can fix load-use on processors that need a load delay slot.

Also do so for fwd_fixup.

[Ralf: Only R2000/R3000 class processors are lacking the the load-user
interlock and even some of those got it retrofitted.  With R2000/R3000
being fairly uncommon these days the impact of this bug should be minor.]
Signed-off-by: Tony Wu <tung7970@gmail.com>
To: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/1768/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

We were unconditionally sending SIGBUS with an empty siginfo on FP
emulator faults.  This differs from what happens when real floating
point hardware would get a fault.

For most faults we need to send SIGSEGV with the faulting address
filled in in the struct siginfo.
Reported-by: Camm Maguire <camm@maguirefamily.org>
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
To: linux-mips@linux-mips.org
Cc: Camm Maguire <camm@maguirefamily.org>
Patchwork: https://patchwork.linux-mips.org/patch/1727/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

TNETD7200 run their CPU clock faster than the default CPU clock we assume.
In order to have the correct loops per jiffies settings, initialize clocks right
before setting mips_hpt_frequency. As a side effect, we can no longer use
msleep in clocks.c which requires other parts of the kernel to be initialized,
so replace these with mdelay.
Signed-off-by: Florian Fainelli <florian@openwrt.org>
To: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/1749/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

Signed-off-by: Florian Fainelli <florian@openwrt.org>
To: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/1748/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

Recent changes to CONFIG_GENERIC_HARDIRQS have caused us to start getting:

warning: (SMP && SYS_SUPPORTS_SMP) selects IRQ_PER_CPU which has unmet direct dependencies (HAVE_GENERIC_HARDIRQS)

Rearranging our Kconfig quiets the message.
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
To: linux-mips@linux-mips.org
Cc: Thomas Gleixner <tglx@linutronix.de>
Patchwork: https://patchwork.linux-mips.org/patch/1757/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/alchemy/devboards/prom.c: In function 'prom_init':
arch/mips/alchemy/devboards/prom.c:60: error: ignoring return value of
'strict_strtoul', declared with attribute warn_unused_result
Signed-off-by: Yoichi Yuasa <yuasa@linux-mips.org>
Cc: linux-mips <linux-mips@linux-mips.org>
Patchwork: https://patchwork.linux-mips.org/patch/1761/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

cc1: warnings being treated as errors
arch/mips/loongson/common/env.c: In function 'prom_init_env':
arch/mips/loongson/common/env.c:49: error: ignoring return value of 'strict_strtol', declared with attribute warn_unused_result
arch/mips/loongson/common/env.c:50: error: ignoring return value of 'strict_strtol', declared with attribute warn_unused_result
arch/mips/loongson/common/env.c:51: error: ignoring return value of 'strict_strtol', declared with attribute warn_unused_result
arch/mips/loongson/common/env.c:52: error: ignoring return value of 'strict_strtol', declared with attribute warn_unused_result
Signed-off-by: Wu Zhangjin <wuzhangjin@gmail.com>
Cc: linux-mips <linux-mips@linux-mips.org>
Patchwork: https://patchwork.linux-mips.org/patch/1762/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

The return value of the vmalloc() call in arch/mips/kernel/vpe.c::vpe_open()
is not checked, so we potentially store a null pointer in v->pbuffer.  Add
a check for a null return and then return -ENOMEM in that case.

[Ralf: The check added by Jesper's original patch is where it logically
should be.  Adding it eleminated the need for the checks in a few other
places, so I removed them.  There still is a zillion of other things that
need to be fixed in this file / API.]
Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/1747/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

If PER_LINUX32 has been set on a 32-bit kernel, only twiddle with the
low-order personality bits, let the upper bits pass through.
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
To: linux-mips@linux-mips.org
Cc: Camm Maguire <camm@maguirefamily.org>
Patchwork: https://patchwork.linux-mips.org/patch/1751/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

The high bits of current->personality carry settings that we don't want to
clobber on each exec.  Only clobber them if the lower bits that indicate
either PER_LINUX or PER_LINUX32 are invalid.

The clobbering prevents us from using useful bits like ADDR_NO_RANDOMIZE.
Reported-by: Camm Maguire <camm@maguirefamily.org>
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Cc: Camm Maguire <camm@maguirefamily.org>
Patchwork: https://patchwork.linux-mips.org/patch/1750/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

This patch fixes the following section mismatch:

	WARNING: arch/mips/built-in.o(.text+0xc): Section mismatch in reference from the
	function jz4740_init_cmdline() to the variable .init.data:arcs_cmdline

While were at it, make jz4740_init_cmdline static as well.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/1755/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

This patch fixes the gpio number for the 6th row of the keyboard matrix.

(And fixes a typo in my name...)
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Cc: linux-mips@linux-mips.org
Cc: stable@kernel.org
Signed-off-by: https://patchwork.linux-mips.org/patch/1754/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

We never needed that (->regs[2] is overwritten on return from syscall paths
with return value of syscall, so storing it there early made no sense) and
with new restart logics since d27240bf7e61d2656de18e158ec910a902030847 it
has become really bad - we lose the original syscall number before the
place where we decide that we might need a syscall restart.

Note that for child we do need the assignment to regs[2] - it won't go
through the normal return from syscall path.

[Ralf: Issue found and reported by Lluís; initial investigations by me;
bug finally found and patch by Al; testing by me and Lluís.]
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Tested-by: Lluís Batlle i Rossell <viriketo@gmail.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

* git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus:
  lguest: populate initial_page_table
  lguest: restore boot speed
  lguest: fix crash lguest_time_init

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ryusuke/nilfs2:
  nilfs2: fix regression of garbage collection ioctl

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
  Input: define separate EVIOCGKEYCODE_V2/EVIOCSKEYCODE_V2
  Input: wacom - add another Bamboo Pen ID (0xd4)

Two x86 patches broke lguest:
1) v2.6.35-492-g72d7c3b3, which changed x86 to use the memblock allocator.

In lguest, the host places linear page tables at the top of mem, which
used to be enough to get us up to the swapper_pg_dir page tables.  With
the first patch, the direct mapping tables used that memory:

Before: kernel direct mapping tables up to 4000000 @ 7000-1a000
After: kernel direct mapping tables up to 4000000 @ 3fed000-4000000

I initially fixed this by lying about the amount of memory we had, so
the kernel wouldn't blatt the lguest boot pagetables (yuk!), but then...

2) v2.6.36-rc8-54-gb40827f, which made x86 boot use initial_page_table.

This was initialized in a part of head_32.S which isn't executed by
lguest; it is then copied into swapper_pg_dir.  So we have to initialize
it; and anyway we switch to it before we blatt the old tables, so that
fixes the previous damage as well.

For the moment, I cut & pasted the code into lguest's boot code, but
next merge window I will merge them.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
To: x86@kernel.org