This patch moves ADC device definition to plat-samsung.
Because that is generic to the S3C64XX and S5P Series SoCs.
Signed-off-by: NNaveen Krishna Ch <ch.naveen@samsung.com>
Signed-off-by: NKukjin Kim <kgene.kim@samsung.com>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

The x86_64 call_rwsem_wait() treats the active state counter part of the
R/W semaphore state as being 16-bit when it's actually 32-bit (it's half
of the 64-bit state).  It should do "decl %edx" not "decw %dx".
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

With F10, model 10, all valid frequencies are in the ACPI _PST table.

Cc: <stable@kernel.org> # 33.x 32.x
Signed-off-by: NMark Langsdorf <mark.langsdorf@amd.com>
LKML-Reference: <1270065406-1814-6-git-send-email-bp@amd64.org>
Signed-off-by: NBorislav Petkov <borislav.petkov@amd.com>
Reviewed-by: NThomas Renninger <trenn@suse.de>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Commit e67a807f ("x86: Fix 'reservetop=' functionality") added a
fixup_early_ioremap() call to parse_reservetop() and declared it
in io.h.

But asm/io.h was only included indirectly - and on some configs
not at all, causing a build failure on those configs.

Cc: Liang Li <liang.li@windriver.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Wang Chen <wangchen@cn.fujitsu.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
LKML-Reference: <1272621711-8683-1-git-send-email-liang.li@windriver.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Upstream PV guests fail to boot because of a NULL pointer in
irq_force_complete_move().  It is possible that xen guests have
irq_desc->chip_data = NULL.

Test for NULL chip_data pointer before attempting to complete an irq move.
Signed-off-by: NPrarit Bhargava <prarit@redhat.com>
LKML-Reference: <20100427152434.16193.49104.sendpatchset@prarit.bos.redhat.com>
Acked-by: NSuresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Cc: <stable@kernel.org> [2.6.33]

The -mfix-loongson2f-jump option provided by latest CVS binutils have fixed
the out-of-order issue of Loongson-2F described in chapter 15 of the
Loongson2F User Manual [1, 2], but introduced some problems.

The option changes all of the jump target to "addr & 0xcfffffff" through the
at($1) register, but for the reboot address of Loongson 2F 0xbfc00000 this is
wrong.  Avoids the problem via telling the assembler to not use the $at
register.

[1] Loongson2F User Manual (Chinese Version)
    http://www.loongson.cn/uploadfile/file/200808211
[2] English Version of Chapter 15:
    http://groups.google.com.hk/group/loongson-dev/msg/e0d2e220958f10a6?dmode=sourceReported-and-tested-by: NLiu Shiwei <liushiwei@gmail.com>
Signed-off-by: NWu Zhangjin <wuzhangjin@gmail.com>
Cc: linux-mips <linux-mips@linux-mips.org>
Patchwork: http://patchwork.linux-mips.org/patch/1109/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Signed-off-by: NWu Zhangjin <wuzhangjin@gmail.com>
Cc: linux-mips <linux-mips@linux-mips.org>
Patchwork: http://patchwork.linux-mips.org/patch/1106/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

With the  "Fixups of Loongson2F" patch [1] having been applied to binutils
for binutils 2.20.1 we now can use it's time to enable the options provided
by the patch to compile the kernel.

Without these fixups, the system may hang if the erratum is triggered.

For more information on these fixups please refer to the following
references.

[1] "Fixups of Loongson2F" patch for binutils(actually for gas)
    http://sourceware.org/ml/binutils/2009-11/msg00387.html
[2] Chapter 15 of "Loongson2F User Manual"(Chinese Version)
    http://www.loongson.cn/uploadfile/file/200808211
[3] Chapter 15 of the English version Loongson 2F User Manual
    http://groups.google.com.hk/group/loongson-dev/msg/e0d2e220958f10a6?dmode=sourceSigned-off-by: NZhang Le <r0bertz@gentoo.org>
Signed-off-by: NWu Zhangjin <wuzhangjin@gmail.com>
Cc: Zhang Le <r0bertz@gentoo.org>
Cc: linux-mips <linux-mips@linux-mips.org>
Patchwork: http://patchwork.linux-mips.org/patch/1106/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

As documented in the  Loongson 2F User Manual [2, 3], the old Loongson2F
series (2F01 / 2F02) have the NOP & JUMP issues which requires workarounds
in the kernel and binutils.  This issue has been rectified in Loongson 2F
series 2F03 so no workarounds needed.

Now that the workarounds [1] adding the the -mfix-loongson2f-nop and
-mfix-loongson2f-jump options have been comitted to the binutils the CVS
repository), we can add the workarounds in the kernel.

The workarounds have no significant side effect on the system but may
decrease performance so we control them through a a new
CPU_LOONGSON2F_WORKAROUNDS config option allowing the users to only enable
it as necessary.

[1] "Fixups of Loongson2F" patch for binutils(actually for gas)
    http://sourceware.org/ml/binutils/2009-11/msg00387.html
[2] Chapter 15 of "Loongson2F User Manual"(Chinese Version)
    http://www.loongson.cn/uploadfile/file/200808211
[3] English Version of the above chapter 15
    http://groups.google.com.hk/group/loongson-dev/msg/e0d2e220958f10a6?dmode=sourceSigned-off-by: NWu Zhangjin <wuzhangjin@gmail.com>
Cc: linux-mips <linux-mips@linux-mips.org>
Patchwork: http://patchwork.linux-mips.org/patch/1105/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Signed-off-by: NFlorian Fainelli <ffainelli@freebox.fr>
To: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/1082/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

the defconfig was out-of-sync since 2.6.30-rc6, update it with the new
symbols and enable BCM6338, 6345, wireless, b43 driver and LEDs support.
Signed-off-by: NFainelli <ffainelli@freebox.fr>
To: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/1081/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

When the oprofile is compiled as a module do_IRQ() is not called in
arch/mips/loongson/lemote-2f/irq.c due to a wrong #ifdef there.
Signed-off-by: NWu Zhangjin <wuzhangjin@gmail.com>
Cc: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/1143/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

There's a typo in the LOONGSON_ADDRWIN_CFG macro. The cpu window mmap
register address should contain the destination parameters not the
source one.  This has not been noticed because the code is only using
source = destination.
Signed-off-by: NArnaud Patard <apatard@mandriva.com>
To: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/1162/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

The check used to determine if uncached accelerated should be used or not
is wrong. The parenthesis are misplaced and making the test fail.
Signed-off-by: NArnaud Patard <apatard@mandriva.com>
To: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/1161/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

This allows to use all display device for instance DISPLAY_OTHER like SM501.
Signed-off-by: NArnaud Patard <apatard@mandriva.com>
To: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/1160/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

It's not "gidum" but "gdium".
Signed-off-by: NArnaud Patard <apatard@mandriva.com>
Cc: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/1159/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

"MIPS: Calculate proper ebase value for 64-bit kernels"
9af43ea080dd5d6c7b34f38261780e5dd43537bc (lmo) rsp.
f6be75d0 (kernel.org) broke some 64-bit
MIPS systems.

Before this we were using XKPHYS/cached as ebase and computed the uncached
xphsys/unchached address for that area. After that commit ebase became a
32-bit compat address and convert does not work anymore.  We now should use
CKSEG1 for this. CKSEG1ADDR does just that in 32-bit and 64-bit.
Signed-off-by: NSebastian Andrzej Siewior <sebastian@breakpoint.cc>
To: Ralf Baechle <ralf@linux-mips.org>
Patchwork: http://patchwork.linux-mips.org/patch/1149/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

For some combinations of PAGE_SIZE and vmbits, it is possible to have
userspace access that are beyond what is covered by the PGD, but within
vmbits.  Such an access would cause the TLB refill handler to load garbage
values for PMD and PTE potentially giving userspace access to parts of the
physical address space to which it is not entitled.

In the TLB refill hot path, we add a single dsrl instruction so we can
check if any bits outside of the range covered by the PGD are set.  In
the vmalloc side we then separate the bad case from the normal vmalloc
case and call tlb_do_page_fault_0 if warranted.  This slows us down a
bit, but has the benefit of yielding deterministic behavior.

[Ralf: Fixed build error for 32-bit kernels.]
[Ralf: Folded lmo commit c8c0e22b2aa3982852b44279638ef37f9aa31b7d into this
 commit.]
Signed-off-by: NDavid Daney <ddaney@caviumnetworks.com>
To: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/1152/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

---

This makes the code somewhat cleaner while reducing the risk of shift
amount overflows when various page table related options are changed.
Signed-off-by: NDavid Daney <ddaney@caviumnetworks.com>
To: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/1154/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

This allows us to clean up the code by not having to explicitly code
checks for shift amounts greater than 32.
Signed-off-by: NDavid Daney <ddaney@caviumnetworks.com>
To: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/1153/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

The MIPS implementation of die() forgets to call notify_die() and thus notifiers
registered via register_die_notifier() are not called.  This results in kgdb not
being activated on exceptions.

The only subtlety is that notify_die declares its regs argument w/o const, so
the const had to be removed from mips die() as well.

[Ralf: Fixed build error for SGI IP22 and IP28 platforms.]
Signed-off-by: NYury Polyanskiy <ypolyans@princeton.edu>
Cc: linux-mips@linux-mips.org
Patchworks: http://patchwork.linux-mips.org/patch/1142/Acked-by: NJason Wessel <jason.wessel@windriver.com>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

---

According to include/asm/sibyte/swarm.h both systems provide a
platform device for the ide controler. Until now the IDE subsystem was
used which is deprecated by now. The same structure can be used with the
PATA driver.
Signed-off-by: NSebastian Andrzej Siewior <sebatian@breakpoint.cc>
Cc: tbm@cyrius.com
Cc: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/1127/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Same issues as SD card detection:  One of both is always triggering and the
handlers take care to shut it up and enable the other.  To avoid messages
about "unbalanced interrupt enable/disable" they must not be automatically
enabled when initally requested.

This was not an issue with the db1200_defconfig due to fortunate timings;
on a build without network chip support the warnings appear.
Signed-off-by: NManuel Lauss <manuel.lauss@gmail.com>
To: Linux-MIPS <linux-mips@linux-mips.org>
Patchwork: http://patchwork.linux-mips.org/patch/1133/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

| arch/mips/pci/pci-sb1250.c: In function sb1250_pcibios_init:
| arch/mips/pci/pci-sb1250.c:257: warning: assignment makes integer from pointer without a cast
| arch/mips/pci/pci-sb1250.c:285: error: MAX_NR_CONSOLES undeclared (first use in this function)
| arch/mips/pci/pci-sb1250.c:285: error: (Each undeclared identifier is reported only once
| arch/mips/pci/pci-sb1250.c:285: error: for each function it appears in.)
Signed-off-by: NSebastian Andrzej Siewior <sebastian@breakpoint.cc>
Cc: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/1136/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

|arch/mips/sibyte/swarm/setup.c:153:
| warning: large integer implicitly truncated to unsigned type

The field was changed in d9b26352 aka ("x86, setup: Store the boot
cursor state").  This patch changes the values back they way they were
before this extra field got introduced.

While here, the other two boards are also converted to C99 initializer.
Signed-off-by: NSebastian Andrzej Siewior <sebastian@breakpoint.cc>
Cc: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/1137/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

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

In the 64-bit kernel we use swapper_pg_dir for three different things.

1) xuseg mappings for kernel threads.

2) vmap mappings for all kernel-space accesses in xkseg.

3) vmap mappings for kernel modules in ksseg (kseg2).

Due to how the TLB refill handlers work, any mapping established in
xkseg or ksseg will also establish a xuseg mapping that should never
be used by the kernel.

In order to be able to use exceptions to trap NULL pointer
dereferences, we need to ensure that nothing is mapped at address
zero.  Since vmap mappings in xkseg are reflected in xuseg, this means
we need to ensure that there are no vmap mappings established at the
start of xkseg.  So we move back VMALLOC_START to avoid establishing
vmap mappings at the start of xkseg.
Signed-off-by: NDavid Daney <ddaney@caviumnetworks.com>
To: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/1129/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

    commit 5a0e3ad6
    Author: Tejun Heo <tj@kernel.org>
    Date:   Wed Mar 24 17:04:11 2010 +0900

        include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

Since a while the few headers included don't drag in <linux/kernel.h>
anymore, thus no more prototype of printk() resulting in:

  CC      arch/mips/nxp/pnx8550/common/reset.o
/home/ralf/src/linux/upstream-linus/arch/mips/nxp/pnx8550/common/reset.c: In function 'pnx8550_machine_restart':
/home/ralf/src/linux/upstream-linus/arch/mips/nxp/pnx8550/common/reset.c:31: error: implicit declaration of function 'printk'
/home/ralf/src/linux/upstream-linus/arch/mips/nxp/pnx8550/common/reset.c:33: error: 'NULL' undeclared (first use in this function)
/home/ralf/src/linux/upstream-linus/arch/mips/nxp/pnx8550/common/reset.c:33: error: (Each undeclared identifier is reported only once
/home/ralf/src/linux/upstream-linus/arch/mips/nxp/pnx8550/common/reset.c:33: error: for each function it appears in.)
make[3]: *** [arch/mips/nxp/pnx8550/common/reset.o] Error 1

Fixed by including <linux/kernel.h>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

MUSB can supply upto 500mA such as, AM3517 and OMAP3EVM Rev >=E and thus
the 'power' field has to hold values above 255.
Signed-off-by: NAjay Kumar Gupta <ajay.gupta@ti.com>
Signed-off-by: NFelipe Balbi <felipe.balbi@nokia.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

When specifying the 'reservetop=0xbadc0de' kernel parameter,
the kernel will stop booting due to a early_ioremap bug that
relates to commit 8827247f.

The root cause of boot failure problem is the value of
'slot_virt[i]' was initialized in setup_arch->early_ioremap_init().
But later in setup_arch, the function 'parse_early_param' will
modify 'FIXADDR_TOP' when 'reservetop=0xbadc0de' being specified.

The simplest fix might be use __fix_to_virt(idx0) to get updated
value of 'FIXADDR_TOP' in '__early_ioremap' instead of reference
old value from slot_virt[slot] directly.

Changelog since v0:

-v1: When reservetop being handled then FIXADDR_TOP get
     adjusted, Hence check prev_map then re-initialize slot_virt and
     PMD based on new FIXADDR_TOP.

-v2: place fixup_early_ioremap hence call early_ioremap_init in
     reserve_top_address  to re-initialize slot_virt and
     corresponding PMD when parse_reservertop

-v3: move fixup_early_ioremap out of reserve_top_address to make
     sure other clients of reserve_top_address like xen/lguest won't
     broken
Signed-off-by: NLiang Li <liang.li@windriver.com>
Tested-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: NYinghai Lu <yinghai@kernel.org>
Acked-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Wang Chen <wangchen@cn.fujitsu.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
LKML-Reference: <1272621711-8683-1-git-send-email-liang.li@windriver.com>
[ fixed three small cleanliness details in fixup_early_ioremap() ]
Signed-off-by: NIngo Molnar <mingo@elte.hu>

The bypassing of this test is a leftover from 2.4 vintage
kernels, and is no longer appropriate, or even used by KGDB.
Currently KGDB uses probe_kernel_write() for all access to
memory via the KGDB core, so it can simply be deleted.

This fixes CVE-2010-1446.

CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: NWufei <fei.wu@windriver.com>
Signed-off-by: NJason Wessel <jason.wessel@windriver.com>

The switch to using GPIOLIB broke the sd/mmc card detection on the
RealView development boards if GPIO_PL061 was not selected.
This patch selects GPIO_PL061 if GPIOLIB is selected.
The sense of the return value from mmc_status has also changed
and is corrected.
Signed-off-by: NColin Tuckley <colin.tuckley@arm.com>
Acked-by: NCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

ACPI _CRS Address Space Descriptors have _MIN, _MAX, and _LEN.  Linux has
been computing Address Spaces as [_MIN to _MIN + _LEN - 1].  Based on the
tests in the bug reports below, Windows apparently uses [_MIN to _MAX].

Per spec (ACPI 4.0, Table 6-40), for _CRS fixed-size, fixed location
descriptors, "_LEN must be (_MAX - _MIN + 1)", and when that's true, it
doesn't matter which way we compute the end.  But of course, there are
BIOSes that don't follow this rule, and we're better off if Linux handles
those exceptions the same way as Windows.

This patch makes Linux use [_MIN to _MAX], as Windows seems to do.  This
effectively reverts d558b483 and 03db42ad and replaces them with
simpler code.

    https://bugzilla.kernel.org/show_bug.cgi?id=14337 (round)
    https://bugzilla.kernel.org/show_bug.cgi?id=15480 (truncate)
Signed-off-by: NBjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

Refresh ps3_defconfig to latest kernel sources and change
these kernel config options:

  o CONFIG_USB_ANNOUNCE_NEW_DEVICES: n -> y
  o CONFIG_USB_EHCI_TT_NEWSCHED: n -> y
  o CONFIG_CMDLINE_BOOL: n -> y
  o CONFIG_CMDLINE: n -> ""
Signed-off-by: NGeoff Levand <geoff@infradead.org>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

This ensures that the translations for unmapped IO mappings or
unmapped memory are properly removed from the MMU hash table
before such an unplug. Without this, the hypervisor refuses the
unplug operations due to those resources still being mapped by
the partition.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

Firmware changed the way it represents memory and cpu affinity on POWER7.
Unfortunately the old method now caps the topology to work around issues
with legacy operating systems. For Linux to get the correct topology we
need to use the new form 1 affinity information.

We set the form 1 field in the client architecture, and if we see "1" in the
ibm,associativity-form property firmware supports form 1 affinity and
we should look at the first field in the ibm,associativity-reference-points
array. If not we use the second field as we always have.
Signed-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

This patch fixes a build failure introduced by 1d839317 ("avr32: use
generic ptrace_resume code") which had the static keyword as a leftover.

  arch/avr32/kernel/ptrace.c:32: error: static declaration of `user_enable_single_step' follows non-static declaration
  include/linux/ptrace.h:268: error: previous declaration of `user_enable_single_step' was here

References:
[1]http://kisskb.ellerman.id.au/kisskb/buildresult/2448162/Signed-off-by: NPeter Huewe <peterhuewe@gmx.de>
Cc: Haavard Skinnemoen <hskinnemoen@atmel.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The following commit broke CONFIG_RELOCATABLE support on FSL Book-E
parts:

commit 549e8152
Author: Paul Mackerras <paulus@samba.org>
Date:   Sat Aug 30 11:43:47 2008 +1000

    powerpc: Make the 64-bit kernel as a position-independent executable

The change to __va and __pa to use PAGE_OFFSET & MEMORY_START causes
problems on the Book-E parts because we don't know MEMORY_START until
after we parse the device tree.  We need __va to work properly to even
parse the device tree so we have a chicken an egg.  So go back to using
he other definition of __va/__pa on CONFIG_BOOKE and use the
PAGE_OFFSET/MEMORY_START version on "Classic" PPC64.

Also updated casts to handle phys_addr_t being a different size from
unsigned long (ie 36-bit physical on PPC32).
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>

When we move a PCI device or assign resources to a device not configured
by the BIOS, we want to avoid the BIOS region below 1MB.  Note that if the
BIOS places devices below 1MB, we leave them there.

See https://bugzilla.kernel.org/show_bug.cgi?id=15744
and https://bugzilla.kernel.org/show_bug.cgi?id=15841Tested-by: NAndy Isaacson <adi@hexapodia.org>
Tested-by: NAndy Bailey <bailey@akamai.com>
Signed-off-by: NBjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

This is a standalone version of VMware Balloon driver.  Ballooning is a
technique that allows hypervisor dynamically limit the amount of memory
available to the guest (with guest cooperation).  In the overcommit
scenario, when hypervisor set detects that it needs to shuffle some
memory, it instructs the driver to allocate certain number of pages, and
the underlying memory gets returned to the hypervisor.  Later hypervisor
may return memory to the guest by reattaching memory to the pageframes and
instructing the driver to "deflate" balloon.

We are submitting a standalone driver because KVM maintainer (Avi Kivity)
expressed opinion (rightly) that our transport does not fit well into
virtqueue paradigm and thus it does not make much sense to integrate with
virtio.

There were also some concerns whether current ballooning technique is the
right thing.  If there appears a better framework to achieve this we are
prepared to evaluate and switch to using it, but in the meantime we'd like
to get this driver upstream.

We want to get the driver accepted in distributions so that users do not
have to deal with an out-of-tree module and many distributions have
"upstream first" requirement.

The driver has been shipping for a number of years and users running on
VMware platform will have it installed as part of VMware Tools even if it
will not come from a distribution, thus there should not be additional
risk in pulling the driver into mainline.  The driver will only activate
if host is VMware so everyone else should not be affected at all.
Signed-off-by: NDmitry Torokhov <dtor@vmware.com>
Cc: Avi Kivity <avi@redhat.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>