zram: simplify and optimize zram_to_dev()

Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Paul Reioux <reioux@gmail.com>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
zram: avoid invalid memory access in zram_exit()

Memory for zram->disk object may have already been freed after returning
from destroy_device(zram), then it's unsafe for zram_reset_device(zram)
to access zram->disk again.

Fix it by holding an extra reference to zram->disk before calling
destroy_device(zram).

Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
zram: destroy all devices on error recovery path in zram_init()

On error recovery path of zram_init(), it leaks the zram device object
causing the failure.

Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
zram: avoid double free in error recovery path of zram_bvec_write()

Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
zram: avoid access beyond the zram device

Function valid_io_request() should verify the entire request doesn't
exceed the zram device, otherwise it will cause invalid memory access.

Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
zram: protect sysfs handler from invalid memory access

Use zram->init_lock to protect access to zram->meta, otherwise it
may cause invalid memory access if zram->meta has been freed by
__zram_reset_device().

Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
Staging: zcache: Update zcache

Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
mm/vmscan.c: Revert last change

Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
fs: add native exFAT support (Samsung OSRC 1.2.4)

http://opensource.samsung.com/reception/receptionSub.do?method=sub&sub=F&searchValue=exfat

Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
block: update BFQ I/O scheduler to v6r2 for 3.0.y

BFQ uses struct cfq_io_context to store its per-process per-device data,
reusing the same code for cic handling of CFQ.  The code is not shared
ATM to minimize the impact of these patches.

This patch introduces a new hlist to each io_context to store all the
cic's allocated by BFQ to allow calling the right destructor on module
unload; the radix tree used for cic lookup needs to be duplicated
because it can contain dead keys inserted by a scheduler and later
retrieved by the other one.

Update the io_context exit and free paths to take care also of
the BFQ cic's.

Change the type of cfqq inside struct cfq_io_context to void *
to use it also for BFQ per-queue data.

A new bfq-specific ioprio_changed field is necessary, too, to avoid
clobbering cfq's one, so switch ioprio_changed to a bitmap, with one
element per scheduler.

Signed-off-by: Paolo Valente <paolo.valente@unimore.it>
Signed-off-by: Arianna Avanzini <avanzini.arianna@gmail.com>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
ARM: 7668/1: fix memset-related crashes caused by recent GCC (4.7.2) … …optimizations

Recent GCC versions (e.g. GCC-4.7.2) perform optimizations based on
assumptions about the implementation of memset and similar functions.
The current ARM optimized memset code does not return the value of
its first argument, as is usually expected from standard implementations.

For instance in the following function:

void debug_mutex_lock_common(struct mutex *lock, struct mutex_waiter *waiter)
{
	memset(waiter, MUTEX_DEBUG_INIT, sizeof(*waiter));
	waiter->magic = waiter;
	INIT_LIST_HEAD(&waiter->list);
}

compiled as:

800554d0 <debug_mutex_lock_common>:
800554d0:       e92d4008        push    {r3, lr}
800554d4:       e1a00001        mov     r0, r1
800554d8:       e3a02010        mov     r2, #16 ; 0x10
800554dc:       e3a01011        mov     r1, #17 ; 0x11
800554e0:       eb04426e        bl      80165ea0 <memset>
800554e4:       e1a03000        mov     r3, r0
800554e8:       e583000c        str     r0, [r3, #12]
800554ec:       e5830000        str     r0, [r3]
800554f0:       e5830004        str     r0, [r3, #4]
800554f4:       e8bd8008        pop     {r3, pc}

GCC assumes memset returns the value of pointer 'waiter' in register r0; causing
register/memory corruptions.

This patch fixes the return value of the assembly version of memset.
It adds a 'mov' instruction and merges an additional load+store into
existing load/store instructions.
For ease of review, here is a breakdown of the patch into 4 simple steps:

Step 1
======
Perform the following substitutions:
ip -> r8, then
r0 -> ip,
and insert 'mov ip, r0' as the first statement of the function.
At this point, we have a memset() implementation returning the proper result,
but corrupting r8 on some paths (the ones that were using ip).

Step 2
======
Make sure r8 is saved and restored when (! CALGN(1)+0) == 1:

save r8:
-       str     lr, [sp, #-4]!
+       stmfd   sp!, {r8, lr}

and restore r8 on both exit paths:
-       ldmeqfd sp!, {pc}               @ Now <64 bytes to go.
+       ldmeqfd sp!, {r8, pc}           @ Now <64 bytes to go.
(...)
        tst     r2, #16
        stmneia ip!, {r1, r3, r8, lr}
-       ldr     lr, [sp], #4
+       ldmfd   sp!, {r8, lr}

Step 3
======
Make sure r8 is saved and restored when (! CALGN(1)+0) == 0:

save r8:
-       stmfd   sp!, {r4-r7, lr}
+       stmfd   sp!, {r4-r8, lr}

and restore r8 on both exit paths:
        bgt     3b
-       ldmeqfd sp!, {r4-r7, pc}
+       ldmeqfd sp!, {r4-r8, pc}
(...)
        tst     r2, #16
        stmneia ip!, {r4-r7}
-       ldmfd   sp!, {r4-r7, lr}
+       ldmfd   sp!, {r4-r8, lr}

Step 4
======
Rewrite register list "r4-r7, r8" as "r4-r8".

Signed-off-by: Ivan Djelic <ivan.djelic@parrot.com>
Reviewed-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Dirk Behme <dirk.behme@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
ARM: 7670/1: fix the memset fix

Commit ("ARM: 7668/1: fix memset-related crashes caused by
recent GCC (4.7.2) optimizations") attempted to fix a compliance issue
with the memset return value.  However the memset itself became broken
by that patch for misaligned pointers.

This fixes the above by branching over the entry code from the
misaligned fixup code to avoid reloading the original pointer.

Also, because the function entry alignment is wrong in the Thumb mode
compilation, that fixup code is moved to the end.

While at it, the entry instructions are slightly reworked to help dual
issue pipelines.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Tested-by: Alexander Holler <holler@ahsoftware.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
build: Fix envsetup for 'parallel' installation

Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
Staging: LMK: Be more aggressive to kill on Screen Off

Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
build: Use Linaro Toolchain 4.8-2013.09

Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
build: Add flags to Makefile

Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>