In the current code, the value of fallback_migratetype that is printed
using the mm_page_alloc_extfrag tracepoint, is the value of the
migratetype *after* it has been set to the preferred migratetype (if the
ownership was changed).  Obviously that wouldn't have been the original
intent.  (We already have a separate 'change_ownership' field to tell
whether the ownership of the pageblock was changed from the
fallback_migratetype to the preferred type.)

The intent of the fallback_migratetype field is to show the migratetype
from which we borrowed pages in order to satisfy the allocation request.
So fix the code to print that value correctly.
Signed-off-by: NSrivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Cody P Schafer <cody@linux.vnet.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The free-page stealing code in __rmqueue_fallback() is somewhat hard to
follow, and has an incredible amount of subtlety hidden inside!

First off, there is a minor bug in the reporting of change-of-ownership of
pageblocks.  Under some conditions, we try to move upto
'pageblock_nr_pages' no.  of pages to the preferred allocation list.  But
we change the ownership of that pageblock to the preferred type only if we
manage to successfully move atleast half of that pageblock (or if
page_group_by_mobility_disabled is set).

However, the current code ignores the latter part and sets the
'migratetype' variable to the preferred type, irrespective of whether we
actually changed the pageblock migratetype of that block or not.  So, the
page_alloc_extfrag tracepoint can end up printing incorrect info (i.e.,
'change_ownership' might be shown as 1 when it must have been 0).

So fixing this involves moving the update of the 'migratetype' variable to
the right place.  But looking closer, we observe that the 'migratetype'
variable is used subsequently for checks such as "is_migrate_cma()".
Obviously the intent there is to check if the *fallback* type is
MIGRATE_CMA, but since we already set the 'migratetype' variable to
start_migratetype, we end up checking if the *preferred* type is
MIGRATE_CMA!!

To make things more interesting, this actually doesn't cause a bug in
practice, because we never change *anything* if the fallback type is CMA.

So, restructure the code in such a way that it is trivial to understand
what is going on, and also fix the above mentioned bug.  And while at it,
also add a comment explaining the subtlety behind the migratetype used in
the call to expand().

[akpm@linux-foundation.org: remove unneeded `inline', small coding-style fix]
Signed-off-by: NSrivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Cody P Schafer <cody@linux.vnet.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix all errors reported by checkpatch and some small spelling mistakes.
Signed-off-by: NPintu Kumar <pintu.k@samsung.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

swap cluster allocation is to get better request merge to improve
performance.  But the cluster is shared globally, if multiple tasks are
doing swap, this will cause interleave disk access.  While multiple tasks
swap is quite common, for example, each numa node has a kswapd thread
doing swap and multiple threads/processes doing direct page reclaim.

ioscheduler can't help too much here, because tasks don't send swapout IO
down to block layer in the meantime.  Block layer does merge some IOs, but
a lot not, depending on how many tasks are doing swapout concurrently.  In
practice, I've seen a lot of small size IO in swapout workloads.

We makes the cluster allocation per-cpu here.  The interleave disk access
issue goes away.  All tasks swapout to their own cluster, so swapout will
become sequential, which can be easily merged to big size IO.  If one CPU
can't get its per-cpu cluster (for example, there is no free cluster
anymore in the swap), it will fallback to scan swap_map.  The CPU can
still continue swap.  We don't need recycle free swap entries of other
CPUs.

In my test (swap to a 2-disk raid0 partition), this improves around 10%
swapout throughput, and request size is increased significantly.

How does this impact swap readahead is uncertain though.  On one side,
page reclaim always isolates and swaps several adjancent pages, this will
make page reclaim write the pages sequentially and benefit readahead.  On
the other side, several CPU write pages interleave means the pages don't
live _sequentially_ but relatively _near_.  In the per-cpu allocation
case, if adjancent pages are written by different cpus, they will live
relatively _far_.  So how this impacts swap readahead depends on how many
pages page reclaim isolates and swaps one time.  If the number is big,
this patch will benefit swap readahead.  Of course, this is about
sequential access pattern.  The patch has no impact for random access
pattern, because the new cluster allocation algorithm is just for SSD.

Alternative solution is organizing swap layout to be per-mm instead of
this per-cpu approach.  In the per-mm layout, we allocate a disk range for
each mm, so pages of one mm live in swap disk adjacently.  per-mm layout
has potential issues of lock contention if multiple reclaimers are swap
pages from one mm.  For a sequential workload, per-mm layout is better to
implement swap readahead, because pages from the mm are adjacent in disk.
But per-cpu layout isn't very bad in this workload, as page reclaim always
isolates and swaps several pages one time, such pages will still live in
disk sequentially and readahead can utilize this.  For a random workload,
per-mm layout isn't beneficial of request merge, because it's quite
possible pages from different mm are swapout in the meantime and IO can't
be merged in per-mm layout.  while with per-cpu layout we can merge
requests from any mm.  Considering random workload is more popular in
workloads with swap (and per-cpu approach isn't too bad for sequential
workload too), I'm choosing per-cpu layout.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: NShaohua Li <shli@fusionio.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Kyungmin Park <kmpark@infradead.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Rafael Aquini <aquini@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The previous patch can expose races, according to Hugh:

swapoff was sometimes failing with "Cannot allocate memory", coming from
try_to_unuse()'s -ENOMEM: it needs to allow for swap_duplicate() failing
on a free entry temporarily SWAP_MAP_BAD while being discarded.

We should use ACCESS_ONCE() there, and whenever accessing swap_map
locklessly; but rather than peppering it throughout try_to_unuse(), just
declare *swap_map with volatile.

try_to_unuse() is accustomed to *swap_map going down racily, but not
necessarily to it jumping up from 0 to SWAP_MAP_BAD: we'll be safer to
prevent that transition once SWP_WRITEOK is switched off, when it's a
waste of time to issue discards anyway (swapon can do a whole discard).

Another issue is:

In swapin_readahead(), read_swap_cache_async() can read a bad swap entry,
because we don't check if readahead swap entry is bad.  This doesn't break
anything but such swapin page is wasteful and can only be freed at page
reclaim.  We should avoid read such swap entry.  And in discard, we mark
swap entry SWAP_MAP_BAD and then switch it to normal when discard is
finished.  If readahead reads such swap entry, we have the same issue, so
we much check if swap entry is bad too.

Thanks Hugh to inspire swapin_readahead could use bad swap entry.

[include Hugh's patch 'swap: fix swapoff ENOMEMs from discard']
Signed-off-by: NShaohua Li <shli@fusionio.com>
Signed-off-by: NHugh Dickins <hughd@google.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Kyungmin Park <kmpark@infradead.org>
Cc: Rafael Aquini <aquini@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

swap can do cluster discard for SSD, which is good, but there are some
problems here:

1. swap do the discard just before page reclaim gets a swap entry and
   writes the disk sectors.  This is useless for high end SSD, because an
   overwrite to a sector implies a discard to original sector too.  A
   discard + overwrite == overwrite.

2. the purpose of doing discard is to improve SSD firmware garbage
   collection.  Idealy we should send discard as early as possible, so
   firmware can do something smart.  Sending discard just after swap entry
   is freed is considered early compared to sending discard before write.
   Of course, if workload is already bound to gc speed, sending discard
   earlier or later doesn't make

3. block discard is a sync API, which will delay scan_swap_map()
   significantly.

4. Write and discard command can be executed parallel in PCIe SSD.
   Making swap discard async can make execution more efficiently.

This patch makes swap discard async and moves discard to where swap entry
is freed.  Discard and write have no dependence now, so above issues can
be avoided.  Idealy we should do discard for any freed sectors, but some
SSD discard is very slow.  This patch still does discard for a whole
cluster.

My test does a several round of 'mmap, write, unmap', which will trigger a
lot of swap discard.  In a fusionio card, with this patch, the test
runtime is reduced to 18% of the time without it, so around 5.5x faster.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: NShaohua Li <shli@fusionio.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Kyungmin Park <kmpark@infradead.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Rafael Aquini <aquini@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

I'm using a fast SSD to do swap.  scan_swap_map() sometimes uses up to
20~30% CPU time (when cluster is hard to find, the CPU time can be up to
80%), which becomes a bottleneck.  scan_swap_map() scans a byte array to
search a 256 page cluster, which is very slow.

Here I introduced a simple algorithm to search cluster.  Since we only
care about 256 pages cluster, we can just use a counter to track if a
cluster is free.  Every 256 pages use one int to store the counter.  If
the counter of a cluster is 0, the cluster is free.  All free clusters
will be added to a list, so searching cluster is very efficient.  With
this, scap_swap_map() overhead disappears.

This might help low end SD card swap too.  Because if the cluster is
aligned, SD firmware can do flash erase more efficiently.

We only enable the algorithm for SSD.  Hard disk swap isn't fast enough
and has downside with the algorithm which might introduce regression (see
below).

The patch slightly changes which cluster is choosen.  It always adds free
cluster to list tail.  This can help wear leveling for low end SSD too.
And if no cluster found, the scan_swap_map() will do search from the end
of last cluster.  So if no cluster found, the scan_swap_map() will do
search from the end of last free cluster, which is random.  For SSD, this
isn't a problem at all.

Another downside is the cluster must be aligned to 256 pages, which will
reduce the chance to find a cluster.  I would expect this isn't a big
problem for SSD because of the non-seek penality.  (And this is the reason
I only enable the algorithm for SSD).
Signed-off-by: NShaohua Li <shli@fusionio.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Kyungmin Park <kmpark@infradead.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Rafael Aquini <aquini@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

set_pageblock_order() may be called when memory hotplug, so need use
'__paginginit' instead of '__init'.

The related warning:

  The function __meminit .free_area_init_node() references
  a function __init .set_pageblock_order().
  If .set_pageblock_order is only used by .free_area_init_node then
  annotate .set_pageblock_order with a matching annotation.
Signed-off-by: NChen Gang <gang.chen@asianux.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When PAGE_SHIFT > 20, the result of "20 - PAGE_SHIFT" is negative. The
previous calculating here will generate an unexpected result. In
addition, if PAGE_SIZE >= 1MB, The memory size of "numentries" was
already integral multiple of 1MB.
Signed-off-by: NJerry Zhou <uulinux@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The use of strict_strtoul() is not preferred, because strict_strtoul() is
obsolete.  Thus, kstrtoul() should be used.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The previous patch doing vmstats for TLB flushes ("mm: vmstats: tlb flush
counters") effectively missed UP since arch/x86/mm/tlb.c is only compiled
for SMP.

UP systems do not do remote TLB flushes, so compile those counters out on
UP.

arch/x86/kernel/cpu/mtrr/generic.c calls __flush_tlb() directly.  This is
probably an optimization since both the mtrr code and __flush_tlb() write
cr4.  It would probably be safe to make that a flush_tlb_all() (and then
get these statistics), but the mtrr code is ancient and I'm hesitant to
touch it other than to just stick in the counters.

[akpm@linux-foundation.org: tweak comments]
Signed-off-by: NDave Hansen <dave.hansen@linux.intel.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

I was investigating some TLB flush scaling issues and realized that we do
not have any good methods for figuring out how many TLB flushes we are
doing.

It would be nice to be able to do these in generic code, but the
arch-independent calls don't explicitly specify whether we actually need
to do remote flushes or not.  In the end, we really need to know if we
actually _did_ global vs.  local invalidations, so that leaves us with few
options other than to muck with the counters from arch-specific code.
Signed-off-by: NDave Hansen <dave.hansen@linux.intel.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

There is a proper macro to get the corresponding swapper address space
from a swap entry.  Instead of directly accessing "swapper_spaces" array,
use the "swap_address_space" macro.
Signed-off-by: NSunghan Suh <sunghan.suh@samsung.com>
Reviewed-by: NBob Liu <bob.liu@oracle.com>
Reviewed-by: NWanpeng Li <liwanp@linux.vnet.ibm.com>
Acked-by: NSeth Jennings <sjenning@linux.vnet.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

correct_wcount and inode in mmap_region() just complicate the code.  This
boolean was needed previously, when deny_write_access() was called before
vma_merge(), now we can simply check VM_DENYWRITE and do
allow_write_access() if it is set.

allow_write_access() checks file != NULL, so this is safe even if it was
possible to use VM_DENYWRITE && !file.  Just we need to ensure we use the
same file which was deny_write_access()'ed, so the patch also moves "file
= vma->vm_file" down after allow_write_access().
Signed-off-by: NOleg Nesterov <oleg@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Colin Cross <ccross@android.com>
Cc: David Rientjes <rientjes@google.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Simple cleanup.  Move "struct inode *inode" variable into "if (file)"
block to simplify the code and avoid the unnecessary check.
Signed-off-by: NOleg Nesterov <oleg@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Colin Cross <ccross@android.com>
Cc: David Rientjes <rientjes@google.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

mmap() doesn't allow the non-anonymous mappings with VM_GROWS* bit set.
In particular this means that mmap_region()->vma_merge(file, vm_flags)
must always fail if "vm_flags & VM_GROWS" is set incorrectly.

So it does not make sense to check VM_GROWS* after we already allocated
the new vma, the only caller, do_mmap_pgoff(), which can pass this flag
can do the check itself.

And this looks a bit more correct, mmap_region() already unmapped the
old mapping at this stage. But if mmap() is going to fail, it should
avoid do_munmap() if possible.

Note: we check VM_GROWS at the end to ensure that do_mmap_pgoff() won't
return EINVAL in the case when it currently returns another error code.

Many thanks to Hugh who nacked the buggy v1.
Signed-off-by: NOleg Nesterov <oleg@redhat.com>
Acked-by: NHugh Dickins <hughd@google.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

A few 80-col gymnastics were cleaned up as a result.

Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

It is possible to swapon a swap area that is too big for the pte width
to handle.

Presently this failure happens silently.

Instead, emit a diagnostic to warn the user.

Testing results, root prompt commands and kernel log messages:

# lvresize /dev/system/swap --size 16G
# mkswap /dev/system/swap
# swapon /dev/system/swap

Jul  7 04:27:22 warfang kernel: Adding 16777212k swap
on /dev/mapper/system-swap.  Priority:-1 extents:1 across:16777212k

# lvresize /dev/system/swap --size 64G
# mkswap /dev/system/swap
# swapon /dev/system/swap

Jul  7 04:27:22 warfang kernel: Truncating oversized swap area, only
using 33554432k out of 67108860k
Jul  7 04:27:22 warfang kernel: Adding 33554428k swap
on /dev/mapper/system-swap.  Priority:-1 extents:1 across:33554428k

[akpm@linux-foundation.org: fix warning]
Signed-off-by: NRaymond Jennings <shentino@gmail.com>
Acked-by: NValdis Kletnieks <valdis.kletnieks@vt.edu>
Reviewed-by: NRik van Riel <riel@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This fixes following errors:
	- ERROR: "(foo*)" should be "(foo *)"
	- ERROR: "foo ** bar" should be "foo **bar"
Signed-off-by: NVladimir Cernov <gg.kaspersky@gmail.com>
Reviewed-by: NPekka Enberg <penberg@kernel.org>
Acked-by: NDavid Rientjes <rientjes@google.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Simple cleanup.  Every user of vma_set_policy() does the same work, this
looks a bit annoying imho.  And the new trivial helper which does
mpol_dup() + vma_set_policy() to simplify the callers.
Signed-off-by: NOleg Nesterov <oleg@redhat.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The driver core clears the driver data to NULL after device_release or
on probe failure.  Thus, it is not needed to manually clear the device
driver data to NULL.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Cc: Jean Delvare <khali@linux-fr.org>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

At one time we used to set the maximum number of scatter gather elements
on all Smart Array controllers to 32.  At some point in time the
firmware began to write the "appropriate" value for each controller into
the config table.  The cciss driver would then read that and set
h->maxsgentries.

        h->maxsgentries = readl(&(h->cfgtable->MaxSGElements);

On the P600 that value is 544.  Under some workloads a significant
performance reduction may result.  This patch forces the P600 to use
only 32 scatter gather elements.  Other controllers are not affected.
Signed-off-by: NMike Miller <mike.miller@hp.com>
Signed-off-by: NDwight (Bud) Brown <bubrown@redhat.com>
Signed-off-by: NTomas Henzl <thenzl@redhat.com>
Acked-by: NStephen M. Cameron <steve.cameron@hp.com>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

mg_times_out() is used only in this file.  Fix the following sparse
warning:

  drivers/block/mg_disk.c:639:6: warning: symbol 'mg_times_out' was not declared. Should it be static?
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Read block device partition table from command line.  The partition used
for fixed block device (eMMC) embedded device.  It is no MBR, save
storage space.  Bootloader can be easily accessed by absolute address of
data on the block device.  Users can easily change the partition.

This code reference MTD partition, source "drivers/mtd/cmdlinepart.c"
About the partition verbose reference
"Documentation/block/cmdline-partition.txt"

[akpm@linux-foundation.org: fix printk text]
[yongjun_wei@trendmicro.com.cn: fix error return code in parse_parts()]
Signed-off-by: NCai Zhiyong <caizhiyong@huawei.com>
Cc: Karel Zak <kzak@redhat.com>
Cc: "Wanglin (Albert)" <albert.wanglin@huawei.com>
Cc: Marius Groeger <mag@sysgo.de>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Brian Norris <computersforpeace@gmail.com>
Cc: Artem Bityutskiy <dedekind@infradead.org>
Signed-off-by: NWei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The usage of strict_strtoul() is not preferred, because strict_strtoul()
is obsolete.  Thus, kstrtoul() should be used.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The use of strict_strtoul() is not preferred, because strict_strtoul() is
obsolete.  Thus, kstrtoul() should be used.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

task_struct->pid/tgid should go away.

1. Change same_thread_group() to use task->signal for comparison.

2. Change has_group_leader_pid(task) to compare task_pid(task) with
   signal->leader_pid.
Signed-off-by: NOleg Nesterov <oleg@redhat.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Sergey Dyasly <dserrg@gmail.com>
Reviewed-by: N"Eric W. Biederman" <ebiederm@xmission.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Call fiemap ioctl(2) with given start offset as well as an desired mapping
range should show extents if possible.  However, we somehow figure out the
end offset of mapping via 'mapping_end -= cpos' before iterating the
extent records which would cause problems if the given fiemap length is
too small to a cluster size, e.g,

Cluster size 4096:
debugfs.ocfs2 1.6.3
        Block Size Bits: 12   Cluster Size Bits: 12

The extended fiemap test utility From David:
https://gist.github.com/anonymous/6172331

# dd if=/dev/urandom of=/ocfs2/test_file bs=1M count=1000
# ./fiemap /ocfs2/test_file 4096 10
start: 4096, length: 10
File /ocfs2/test_file has 0 extents:
#	Logical          Physical         Length           Flags
	^^^^^ <-- No extent is shown

In this case, at ocfs2_fiemap(): cpos == mapping_end == 1. Hence the
loop of searching extent records was not executed at all.

This patch remove the in question 'mapping_end -= cpos', and loops
until the cpos is larger than the mapping_end as usual.

# ./fiemap /ocfs2/test_file 4096 10
start: 4096, length: 10
File /ocfs2/test_file has 1 extents:
#	Logical          Physical         Length           Flags
0:	0000000000000000 0000000056a01000 0000000006a00000 0000
Signed-off-by: NJie Liu <jeff.liu@oracle.com>
Reported-by: NDavid Weber <wb@munzinger.de>
Tested-by: NDavid Weber <wb@munzinger.de>
Cc: Sunil Mushran <sunil.mushran@gmail.com>
Cc: Mark Fashen <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Variable ip in dlmfs_get_root_inode() is defined but not used.  So clean
it up.
Signed-off-by: NJoseph Qi <joseph.qi@huawei.com>
Reviewed-by: NJie Liu <jeff.liu@oracle.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

In o2hb_shutdown_slot() and o2hb_check_slot(), since event is defined as
local, it is only valid during the call stack.  So the following tiny race
case may happen in a multi-volumes mounted environment:

o2hb-vol1                         o2hb-vol2
1) o2hb_shutdown_slot
allocate local event1
2) queue_node_event
add event1 to global o2hb_node_events
                                  3) o2hb_shutdown_slot
                                  allocate local event2
                                  4) queue_node_event
                                  add event2 to global o2hb_node_events
                                  5) o2hb_run_event_list
                                  delete event1 from o2hb_node_events
6) o2hb_run_event_list
event1 empty, return
7) o2hb_shutdown_slot
event1 lifecycle ends
                                  8) o2hb_fire_callbacks
                                  event1 is already *invalid*

This patch lets it wait on o2hb_callback_sem when another thread is firing
callbacks.  And for performance consideration, we only call
o2hb_run_event_list when there is an event queued.
Signed-off-by: NJoyce <xuejiufei@huawei.com>
Signed-off-by: NJoseph Qi <joseph.qi@huawei.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Since o2nm_get_node_by_num() may return NULL, we add this check in
o2net_accept_one() to avoid possible NULL pointer dereference.
Signed-off-by: NJoseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Code in o2net_handler_tree_lookup() may be corrupted by mistake.  So
adjust it to promote readability.
Signed-off-by: NJoseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

In ocfs2_remove_inode_range(), there is a memory leak.  The variable path
has allocated memory with ocfs2_new_path_from_et(), but it is not free.
Signed-off-by: NYounger Liu <younger.liu@huawei.com>
Reviewed-by: NJie Liu <jeff.liu@oracle.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

In ocfs2_reflink_xattr_rec(), meta_ac and data_ac are allocated by calling
ocfs2_lock_reflink_xattr_rec_allocators().

Once an error occurs when allocating *data_ac, it frees *meta_ac which is
allocated before.  Here it mistakenly sets meta_ac to NULL but *meta_ac.
Then ocfs2_reflink_xattr_rec() will try to free meta_ac again which is
already invalid.
Signed-off-by: NJoseph Qi <joseph.qi@huawei.com>
Reviewed-by: NJie Liu <jeff.liu@oracle.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

dlm_do_local_recovery_cleanup() should force clean refmap if the owner of
lockres is UNKNOWN.  Otherwise node may hang when umounting filesystems.
Here's the situation:

	Node1                                    Node2
dlmlock()
  -> dlm_get_lock_resource()
send DLM_MASTER_REQUEST_MSG to
other nodes.

                                       trying to master this lockres,
                                       return MAYBE.

selected as the master of lockresA,
set mle->master to Node1,
and do assert_master,
send DLM_ASSERT_MASTER_MSG to Node2.
                                       Node 2 has interest on lockresA
                                       and return
                                       DLM_ASSERT_RESPONSE_MASTERY_REF
                                       then something happened and
                                       Node2 crashed.

Receiving DLM_ASSERT_RESPONSE_MASTERY_REF, set Node2 into refmap, and keep
sending DLM_ASSERT_MASTER_MSG to other nodes

o2hb found node2 down, calling dlm_hb_node_down() -->
dlm_do_local_recovery_cleanup() the master of lockresA is still UNKNOWN,
no need to call dlm_free_dead_locks().

Set the master of lockresA to Node1, but Node2 stills remains in refmap.

When Node1 umount, it found that the refmap of lockresA is not empty and
attempted to migrate it to Node2, But Node2 is already down, so umount
hang, trying to migrate lockresA again and again.
Signed-off-by: Njoyce <xuejiufei@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Jie Liu <jeff.liu@oracle.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

In ocfs2_xattr_set(), if ocfs2_start_trans failed, meta_ac and data_ac
should be free.  Otherwise, It would lead to a memory leak.
Signed-off-by: NYounger Liu <younger.liu@huawei.com>
Cc: Joseph Qi <joseph.qi@huawei.com>
Reviewed-by: NJie Liu <jeff.liu@oracle.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

In ocfs2_xattr_value_attach_refcount(), if error occurs when calling
ocfs2_xattr_get_clusters(), it will go with unexpected behavior since
local variables p_cluster, num_clusters and ext_flags are declared without
initialization.
Signed-off-by: NJoseph Qi <joseph.qi@huawei.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Acked-by: NJie Liu <jeff.liu@oracle.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The ocfs2 path is not properly freed which leads to a memory leak at
__ocfs2_move_extents().

This patch stops the leaks of the ocfs2_path structure.
Signed-off-by: NJie Liu <jeff.liu@oracle.com>
Reviewed-by: NYounger Liu <younger.liu@huawei.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

In ocfs2_attach_refcount_tree() and ocfs2_duplicate_extent_list(), if
error occurs when calling ocfs2_get_clusters(), it will go with
unexpected behavior as local variables p_cluster, num_clusters and
ext_flags are declared without initialization.
Signed-off-by: NJoseph Qi <joseph.qi@huawei.com>
Reviewed-by: NJie Liu <jeff.liu@oracle.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

In ocfs2_acl_from_xattr(), if size is less than sizeof(struct
posix_acl_entry), it returns ERR_PTR(-EINVAL) directly.  Then assign (size
/ sizeof(struct posix_acl_entry)) to count which will be at least 1, that
means the following branch (count < 0) and (count == 0) will never be
true.
Signed-off-by: NJoseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Acked-by: NJoel Becker <jlbec@evilplan.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>