Add function to direct Legacy VGA I/O traffic to correct I/O Hub.
Signed-off-by: NMike Travis <travis@sgi.com>
LKML-Reference: <201002022238.o12McEbi018727@imap1.linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Robin Holt <holt@sgi.com>
Cc: Jack Steiner <steiner@sgi.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: David Airlie <airlied@linux.ie>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Now that the previous commit made it possible to do the personality
setting at the point of no return, we do just that for ELF binaries.
And suddenly all the reasons for that insane TIF_ABI_PENDING bit go
away, and we can just make SET_PERSONALITY() just do the obvious thing
for a 32-bit compat process.

Everything becomes much more straightforward this way.
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Cc: stable@kernel.org
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

CONFIG_X86_CPU_DEBUG, which provides some parsed versions of the x86
CPU configuration via debugfs, has caused boot failures on real
hardware.  The value of this feature has been marginal at best, as all
this information is already available to userspace via generic
interfaces.

Causes crashes that have not been fixed + minimal utility -> remove.

See the referenced LKML thread for more information.
Reported-by: NOzan Çağlayan <ozan@pardus.org.tr>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
LKML-Reference: <alpine.LFD.2.00.1001221755320.13231@localhost.localdomain>
Cc: Jaswinder Singh Rajput <jaswinder@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: <stable@kernel.org>

Commit d1c84f79
leads to a regression when microcode_amd.c is compiled into the kernel.
It causes a big boot delay because the firmware is not available.
See http://marc.info/?l=linux-kernel&m=126267290920060

It also renders the reload sysfs attribute useless.
Fixing this is too intrusive for an -rc5 kernel.

Thus I'd like to restore the microcode loading behaviour of kernel
2.6.32.

CC: Gene Heskett <gene.heskett@verizon.net>
Signed-off-by: NAndreas Herrmann <andreas.herrmann3@amd.com>
LKML-Reference: <20100122203456.GB13792@alberich.amd.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

HPET MSI on platforms with ATI SB700/SB800 as they seem to have some
side-effects on floppy DMA. Do not use HPET MSI on such platforms.

Original problem report from Mark Hounschell
http://lkml.indiana.edu/hypermail/linux/kernel/0912.2/01118.html

[ This patch needs to go to stable as well. But, there are some
  conflicts that prevents the patch from going as is. I can
  rebase/resubmit to stable once the patch goes upstream.
  hpa: still Cc:'ing stable@ as an FYI. ]
Tested-by: NMark Hounschell <markh@compro.net>
Signed-off-by: NVenkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Cc: <stable@kernel.org>
LKML-Reference: <20100121190952.GA32523@linux-os.sc.intel.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Propagate the ANY bit into the fixed counter config for v3 and higher.
Signed-off-by: NStephane Eranian <eranian@google.com>
[a.p.zijlstra@chello.nl: split from larger patch]
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <4b5430c6.0f975e0a.1bf9.ffff85fe@mx.google.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Add function for determining the revision id of the SGI UV
node controller chip (HUB). This function is needed in a
subsequent patch.
Signed-off-by: NJack Steiner <steiner@sgi.com>
LKML-Reference: <20100112210904.GA24546@sgi.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Someone isn't reading their build output: Move the definition
out of the exported header.
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Cc: linux-kernel@vger.kernelorg
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Callers of copy_from_user() expect it to return the number of bytes
it could not copy. In no case it is supposed to return -EFAULT.

In case of a detected buffer overflow just return the requested
length. In addition one could think of a memset that would clear
the size of the target object.

[ hpa: code is not in .32 so not needed for -stable ]
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Acked-by: NArjan van de Ven <arjan@linux.intel.com>
LKML-Reference: <20100105131911.GC5480@osiris.boeblingen.de.ibm.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

The wrong address was being used to write the SCIR led regs on remote
hubs.  Also, there was an inconsistency between how BIOS and the kernel
indexed these regs.  Standardize on using the lower 6 bits of the APIC
ID as the index.

This patch fixes the problem of writing to an errant address to a
cpu # >= 64.
Signed-off-by: NMike Travis <travis@sgi.com>
Reviewed-by: NJack Steiner <steiner@sgi.com>
Cc: stable@kernel.org
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The wrong address was being used to write the SCIR led regs on
remote hubs.  Also, there was an inconsistency between how BIOS
and the kernel indexed these regs.  Standardize on using the
lower 6 bits of the APIC ID as the index.

This patch fixes the problem of writing to an errant address to
a cpu # >= 64.
Signed-off-by: NMike Travis <travis@sgi.com>
Reviewed-by: NJack Steiner <steiner@sgi.com>
Cc: Robin Holt <holt@sgi.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: stable@kernel.org
LKML-Reference: <4B3922F9.3060905@sgi.com>
[ v2: fix a number of annoying checkpatch artifacts and whitespace noise ]
Signed-off-by: NIngo Molnar <mingo@elte.hu>

User space may not want to overwrite asynchronously changing VCPU event
states on write-back. So allow to skip nmi.pending and sipi_vector by
setting corresponding bits in the flags field of kvm_vcpu_events.

[avi: advertise the bits in KVM_GET_VCPU_EVENTS]
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

The only thing arch-specific about calling _PDC is what bits get
set in the input obj_list buffer.

There's no need for several levels of indirection to twiddle those
bits. Additionally, since we're just messing around with a buffer,
we can simplify the interface; no need to pass around the entire
struct acpi_processor * just to get at the buffer.

Cc: Tony Luck <tony.luck@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: NAlex Chiang <achiang@hp.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

arch dependent helper function that tells us if we should attempt to
evaluate _PDC on this machine or not.

The x86 implementation assumes that the CPUs in the machine must be
homogeneous, and that you cannot mix CPUs of different vendors.

Cc: Tony Luck <tony.luck@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: NAlex Chiang <achiang@hp.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

John Blackwood reported:
> on an older Dell PowerEdge 6650 system with 8 cpus (4 are hyper-threaded),
> and  32 bit (x86) kernel, once you change the irq smp_affinity of an irq
> to be less than all cpus in the system, you can never change really the
> irq smp_affinity back to be all cpus in the system (0xff) again,
> even though no error status is returned on the "/bin/echo ff >
> /proc/irq/[n]/smp_affinity" operation.
>
> This is due to that fact that BAD_APICID has the same value as
> all cpus (0xff) on 32bit kernels, and thus the value returned from
> set_desc_affinity() via the cpu_mask_to_apicid_and() function is treated
> as a failure in set_ioapic_affinity_irq_desc(), and no affinity changes
> are made.

set_desc_affinity() is already checking if the incoming cpu mask
intersects with the cpu online mask or not. So there is no need
for the apic op cpu_mask_to_apicid_and() to check again
and return BAD_APICID.

Remove the BAD_APICID return value from cpu_mask_to_apicid_and()
and also fix set_desc_affinity() to return -1 instead of using BAD_APICID
to represent error conditions (as cpu_mask_to_apicid_and() can return
logical or physical apicid values and BAD_APICID is really to represent
bad physical apic id).
Reported-by: NJohn Blackwood <john.blackwood@ccur.com>
Root-caused-by: NJohn Blackwood <john.blackwood@ccur.com>
Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com>
LKML-Reference: <1261103386.2535.409.camel@sbs-t61>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

perf events, x86/stacktrace: Fix performance/softlockup by providing a special frame pointer-only stack walker

It's just wasteful for stacktrace users like perf to walk
through every entries on the stack whereas these only accept
reliable ones, ie: that the frame pointer validates.

Since perf requires pure reliable stacktraces, it needs a stack
walker based on frame pointers-only to optimize the stacktrace
processing.

This might solve some near-lockup scenarios that can be triggered
by call-graph tracing timer events.
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1261024834-5336-2-git-send-regression-fweisbec@gmail.com>
[ v2: fix for modular builds and small detail tidyup ]
Signed-off-by: NIngo Molnar <mingo@elte.hu>

The current print_context_stack helper that does the stack
walking job is good for usual stacktraces as it walks through
all the stack and reports even addresses that look unreliable,
which is nice when we don't have frame pointers for example.

But we have users like perf that only require reliable
stacktraces, and those may want a more adapted stack walker, so
lets make this function a callback in stacktrace_ops that users
can tune for their needs.
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1261024834-5336-1-git-send-regression-fweisbec@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

xsave_cntxt_init() does something like:

	cpuid(0xd, ..);	// find out what features FP/SSE/.. etc are supported

	xsetbv();	// enable the features known to OS

	cpuid(0xd, ..);	// find out the size of the context for features enabled

Depending on what features get enabled in xsetbv(), value of the
cpuid.eax=0xd.ecx=0.ebx changes correspondingly (representing the
size of the context that is enabled).

As we don't have volatile keyword for native_cpuid(), gcc 4.1.2
optimizes away the second cpuid and the kernel continues to use
the cpuid information obtained before xsetbv(), ultimately leading to kernel
crash on processors supporting more state than the legacy FP/SSE.

Add "volatile" for native_cpuid().
Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com>
LKML-Reference: <1261009542.2745.55.camel@sbs-t61.sc.intel.com>
Cc: stable@kernel.org
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Randy Dunlap reported the following build error:

"When CONFIG_SMP=n, CONFIG_X86_MSR=m:

ERROR: "msrs_free" [drivers/edac/amd64_edac_mod.ko] undefined!
ERROR: "msrs_alloc" [drivers/edac/amd64_edac_mod.ko] undefined!"

This is due to the fact that <arch/x86/lib/msr.c> is conditioned on
CONFIG_SMP and in the UP case we have only the stubs in the header.
Fork off SMP functionality into a new file (msr-smp.c) and build
msrs_{alloc,free} unconditionally.
Reported-by: NRandy Dunlap <randy.dunlap@oracle.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: NBorislav Petkov <petkovbb@gmail.com>
LKML-Reference: <20091216231625.GD27228@liondog.tnic>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Use NodeId MSR to get NodeId and number of nodes per processor.
Signed-off-by: NAndreas Herrmann <andreas.herrmann3@amd.com>
LKML-Reference: <20091216144355.GB28798@alberich.amd.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

* hpux_pipe() - no need to take BKL
* sys32_pipe() in arch/x86/ia32 and xtensa_pipe() in arch/xtensa -
	no need at all, since both functions are open-coded sys_pipe()
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Create a function to generate the value that is written to the UV hub MMR
to cause an IPI interrupt to be sent.  The function will be used in the
GRU message queue error recovery code that sends IPIs to nodes in remote
partitions.
Signed-off-by: NJack Steiner <steiner@sgi.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The UV BIOS has moved the location of some of their pointers to the
"partition reserved page" from memory into a uv hub MMR.  The GRU does not
support bcopy operations from MMR space so we need to special case the MMR
addresses using VLOAD operations.

Additionally, the BIOS call for registering a message queue watchlist has
removed the 'blade' value and eliminated the structure that was being
passed in.  This is also reflected in this patch.
Signed-off-by: NRobin Holt <holt@sgi.com>
Cc: Jack Steiner <steiner@sgi.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Provide a mechanism for determining if a global physical address is
pointing to a UV hub MMR.
Signed-off-by: NRobin Holt <holt@sgi.com>
Cc: Jack Steiner <steiner@sgi.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The UV BIOS has been updated to implement some of our interface
functionality differently than originally expected.  These patches update
the kernel to the bios implementation and include a few minor bug fixes
which prevent us from doing significant testing on real hardware.

This patch:

For SGI UV systems, translate from a global physical address back to a
socket physical address.  This does nothing to ensure the socket physical
address is actually addressable by the kernel.  That is the responsibility
of the user of the function.
Signed-off-by: NRobin Holt <holt@sgi.com>
Cc: Jack Steiner <steiner@sgi.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

dma_mask is, when interpreted as address, the last valid byte, and hence
comparison msut also be done using the last valid of the buffer in
question.

Also fix the open-coded instances in lib/swiotlb.c.
Signed-off-by: NJan Beulich <jbeulich@novell.com>
Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Becky Bruce <beckyb@kernel.crashing.org>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Currently all architectures but microblaze unconditionally define
USE_ELF_CORE_DUMP.  The microblaze omission seems like an error to me, so
let's kill this ifdef and make sure we are the same everywhere.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Acked-by: NHugh Dickins <hugh.dickins@tiscali.co.uk>
Cc: <linux-arch@vger.kernel.org>
Cc: Michal Simek <michal.simek@petalogix.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Suggested by Roland.

Implement user_single_step_siginfo() for x86.  Extract this code from
send_sigtrap().

Since x86 calls tracehook_report_syscall_exit(step => 0) the new helper is
not used yet.
Signed-off-by: NOleg Nesterov <oleg@redhat.com>
Acked-by: NRoland McGrath <roland@redhat.com>
Cc: <linux-arch@vger.kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Clean up write_tsc() and write_tscp_aux() by replacing
hardcoded values.

No change in functionality.
Signed-off-by: NSheng Yang <sheng@linux.intel.com>
Cc: Avi Kivity <avi@redhat.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
LKML-Reference: <1260942485-19156-4-git-send-email-sheng@linux.intel.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

With generic modular drivers handling all of this stuff, the
geode-specific code can go away.  The cs5535-gpio, cs5535-mfgpt, and
cs5535-clockevt drivers now handle this.
Signed-off-by: NAndres Salomon <dilinger@collabora.co.uk>
Cc: Jordan Crouse <jordan@cosmicpenguin.net>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Chris Ball <cjb@laptop.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

..and include them in the lxfb/gxfb drivers rather than asm/geode.h (where
possible).
Signed-off-by: NAndres Salomon <dilinger@collabora.co.uk>
Cc: Jordan Crouse <jordan@cosmicpenguin.net>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Chris Ball <cjb@laptop.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NAndres Salomon <dilinger@collabora.co.uk>
Cc: Jordan Crouse <jordan@cosmicpenguin.net>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Chris Ball <cjb@laptop.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The only thing that uses this is the reboot_fixups code.
Signed-off-by: NAndres Salomon <dilinger@collabora.co.uk>
Cc: Jordan Crouse <jordan@cosmicpenguin.net>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Chris Ball <cjb@laptop.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This is based on the old code on arch/x86/kernel/mfgpt_32.c, except it's
not x86 specific, it's modular, and it makes use of a PCI BAR rather than
a random MSR.  Currently module unloading is not supported; it's uncertain
whether or not it can be made work with the hardware.

[akpm@linux-foundation.org: add X86 dependency]
Signed-off-by: NAndres Salomon <dilinger@collabora.co.uk>
Cc: Jordan Crouse <jordan@cosmicpenguin.net>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Chris Ball <cjb@laptop.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Previously, OLPC support for the mic extensions was only enabled in the
ALSA driver if CONFIG_OLPC and CONFIG_MGEODE_LX were both set.  This was
because the old geode GPIO code was written in a manner that assumed
CONFIG_MGEODE_LX.  With the new cs553x-gpio driver, this is no longer the
case; as such, we can drop the requirement on CONFIG_MGEODE_LX and instead
include a requirement on GPIOLIB.

We use the generic GPIO API rather than the cs553x-specific API.
Signed-off-by: NAndres Salomon <dilinger@collabora.co.uk>
Cc: Takashi Iwai <tiwai@suse.de>
Cc: Jordan Crouse <jordan@cosmicpenguin.net>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This creates a CS5535/CS5536 GPIO driver which uses a gpio_chip backend
(allowing GPIO users to use the generic GPIO API if desired) while also
allowing architecture-specific users directly (via the cs5535_gpio_*
functions).

Tested on an OLPC machine.  Some Leemotes also use CS5536 (with a mips
cpu), which is why this is in drivers/gpio rather than arch/x86.
Currently, it conflicts with older geode GPIO support; once MFGPT support
is reworked to also be more generic, the older geode code will be removed.
Signed-off-by: NAndres Salomon <dilinger@collabora.co.uk>
Cc: Takashi Iwai <tiwai@suse.de>
Cc: Jordan Crouse <jordan@cosmicpenguin.net>
Cc: David Brownell <david-b@pacbell.net>
Reviewed-by: NAlessandro Zummo <a.zummo@towertech.it>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Move definition of NUMA_NO_NODE from ia64 and x86_64 arch specific headers
to generic header 'linux/numa.h' for use in generic code.  NUMA_NO_NODE
replaces bare '-1' where it's used in this series to indicate "no node id
specified".  Ultimately, it can be used to replace the -1 elsewhere where
it is used similarly.
Signed-off-by: NLee Schermerhorn <lee.schermerhorn@hp.com>
Acked-by: NDavid Rientjes <rientjes@google.com>
Acked-by: NMel Gorman <mel@csn.ul.ie>
Reviewed-by: NAndi Kleen <andi@firstfloor.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Nishanth Aravamudan <nacc@us.ibm.com>
Cc: Adam Litke <agl@us.ibm.com>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Eric Whitney <eric.whitney@hp.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The commit f4780ca0 moves
swiotlb initialization before dma32_free_bootmem(). It's
supposed to fix a bug that the commit
75f1cdf1 introduced, we
initialize SWIOTLB right after dma32_free_bootmem so we wrongly
steal memory area allocated for GART with broken BIOS earlier.

However, the above commit introduced another problem, which
likely breaks machines with huge amount of memory. Such a box
use the majority of DMA32_ZONE so there is no memory for
swiotlb.

With this patch, the x86 IOMMU initialization sequence are:

1. We set swiotlb to 1 in the case of (max_pfn > MAX_DMA32_PFN
   && !no_iommu). If swiotlb usage is forced by the boot option,
   we go to the step 3 and finish (we don't try to detect IOMMUs).

2. We call the detection functions of all the IOMMUs. The
   detection function sets x86_init.iommu.iommu_init to the IOMMU
   initialization function (so we can avoid calling the
   initialization functions of all the IOMMUs needlessly).

3. We initialize swiotlb (and set dma_ops to swiotlb_dma_ops) if
   swiotlb is set to 1.

4. If the IOMMU initialization function doesn't need swiotlb
   (e.g. the initialization is sucessful) then sets swiotlb to zero.

5. If we find that swiotlb is set to zero, we free swiotlb
   resource.
Reported-by: NYinghai Lu <yinghai@kernel.org>
Reported-by: NRoland Dreier <rdreier@cisco.com>
Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
LKML-Reference: <20091215204729A.fujita.tomonori@lab.ntt.co.jp>
Tested-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Name space cleanup for rwlock functions. No functional change.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Acked-by: NPeter Zijlstra <peterz@infradead.org>
Acked-by: NDavid S. Miller <davem@davemloft.net>
Acked-by: NIngo Molnar <mingo@elte.hu>
Cc: linux-arch@vger.kernel.org

Not strictly necessary for -rt as -rt does not have non sleeping
rwlocks, but it's odd to not have a consistent naming convention.

No functional change.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Acked-by: NPeter Zijlstra <peterz@infradead.org>
Acked-by: NDavid S. Miller <davem@davemloft.net>
Acked-by: NIngo Molnar <mingo@elte.hu>
Cc: linux-arch@vger.kernel.org