fuse: add basic support of iovec[] to fuse_req

The patch allows fuse_req to refer to array of iovec-s describing
layout of user-data over req->pages. fuse_copy_pages() is re-worked to
support both cased: former layout where pages[] corresponded to <buf, len>
and newer one where pages[] corresponds to iovec[].

Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com>
fuse: re-work fuse_get_user_pages() to operate on iovec[]

Now fuse_get_user_pages() takes iovec[] as argument and packs so much data
from it to req->pages[] as possible.

Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com>
fuse: re-work fuse_direct_io() to operate on iovec[]

The patch transparently passes iovec[] argument from fuse_direct_io()
to fuse_get_user_pages() hoping that the latter would fill req with
some part of iovec[].

Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com>
block: avoid unnecessary plug should_sort test.

If request_count >= BLK_MAX_REQUEST_COUNT,then it will exec
blk_flush_plug_list which plug all request.So no need to do plug->should_sort test.

Signed-off-by: Jianpeng Ma <majianpeng@gmail.com>
block: Remove unnecessary requests sort.

When adding request to plug,it already sort.So there is not unnecessary.

Signed-off-by: Jianpeng Ma <majianpeng@gmail.com>
block: Fix bad range check in bio_sector_offset

DM would occasionally end up splitting data integrity-enabled requests
incorrectly. The culprit was a bad range check in bio_sector_offset.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
x86,mm: make pagefault killable

When an oom killing occurs, almost all processes are getting stuck at the
following two points.

	1) __alloc_pages_nodemask
	2) __lock_page_or_retry

1) is not very problematic because TIF_MEMDIE leads to an allocation
failure and getting out from page allocator.

2) is more problematic.  In an OOM situation, zones typically don't have
page cache at all and memory starvation might lead to greatly reduced IO
performance.  When a fork bomb occurs, TIF_MEMDIE tasks don't die quickly,
meaning that a fork bomb may create new process quickly rather than the
oom-killer killing it.  Then, the system may become livelocked.

This patch makes the pagefault interruptible by SIGKILL.

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: Matthew Wilcox <willy@linux.intel.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
ARM: 7178/1: fault.c: Port OOM changes into do_page_fault

Commit d065bd810b6deb67d4897a14bfe21f8eb526ba99
(mm: retry page fault when blocking on disk transfer) and
commit 37b23e0525d393d48a7d59f870b3bc061a30ccdb
(x86,mm: make pagefault killable)

The above commits introduced changes into the x86 pagefault handler
for making the page fault handler retryable as well as killable.

These changes reduce the mmap_sem hold time, which is crucial
during OOM killer invocation.

Port these changes to ARM.

Without these changes, my ARM board encounters many hang and livelock
scenarios.
After applying this patch, OOM feature performance improves according to
my testing.

Signed-off-by: Kautuk Consul <consul.kautuk@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

Conflicts:

	arch/arm/mm/fault.c
modified for Tuna kernel from Mainline by faux123
readahead: fault retry breaks mmap file read random detection

.fault now can retry.  The retry can break state machine of .fault.  In
filemap_fault, if page is miss, ra->mmap_miss is increased.  In the second
try, since the page is in page cache now, ra->mmap_miss is decreased.  And
these are done in one fault, so we can't detect random mmap file access.

Add a new flag to indicate .fault is tried once.  In the second try, skip
ra->mmap_miss decreasing.  The filemap_fault state machine is ok with it.

I only tested x86, didn't test other archs, but looks the change for other
archs is obvious, but who knows :)

Signed-off-by: Shaohua Li <shaohua.li@xxxxxxxxxxxx>
Cc: Rik van Riel <riel@xxxxxxxxxx>
Cc: Wu Fengguang <fengguang.wu@xxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
modified for Tuna kernel from Linux Mainline by faux123
block: reject invalid queue attribute values

Instead of using simple_strtoul which "converts" invalid numbers to 0,
use strict_strtoul and perform error checking to ensure that userspace
passes us a valid unsigned long. This addresses problems with functions
such as writev, which might want to write a trailing newline -- the
newline should rightfully be rejected, but the value preceeding it
should be preserved.

Fixes BZ#46981.

Signed-off-by: Dave Reisner <dreisner@archlinux.org>
Kernel Version: ak.085.jb.eva01