Commit graph

417840 commits

Author SHA1 Message Date
Davidlohr Bueso
1f1cd7054f mm/mlock: prepare params outside critical region
All mlock related syscalls prepare lock limits, lengths and start
parameters with the mmap_sem held.  Move this logic outside of the
critical region.  For the case of mlock, continue incrementing the
amount already locked by mm->locked_vm with the rwsem taken.

Signed-off-by: Davidlohr Bueso <davidlohr@hp.com>
Cc: Rik van Riel <riel@redhat.com>
Reviewed-by: Michel Lespinasse <walken@google.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:44 -08:00
Davidlohr Bueso
363ee17f0f mm/mmap.c: add mlock_future_check() helper
Both do_brk and do_mmap_pgoff verify that we are actually capable of
locking future pages if the corresponding VM_LOCKED flags are used.
Encapsulate this logic into a single mlock_future_check() helper
function.

Signed-off-by: Davidlohr Bueso <davidlohr@hp.com>
Cc: Rik van Riel <riel@redhat.com>
Reviewed-by: Michel Lespinasse <walken@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:44 -08:00
Jerome Marchand
49f0ce5f92 mm: add overcommit_kbytes sysctl variable
Some applications that run on HPC clusters are designed around the
availability of RAM and the overcommit ratio is fine tuned to get the
maximum usage of memory without swapping.  With growing memory, the
1%-of-all-RAM grain provided by overcommit_ratio has become too coarse
for these workload (on a 2TB machine it represents no less than 20GB).

This patch adds the new overcommit_kbytes sysctl variable that allow a
much finer grain.

[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: fix nommu build]
Signed-off-by: Jerome Marchand <jmarchan@redhat.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:44 -08:00
Mel Gorman
aec6a8889a mm, show_mem: remove SHOW_MEM_FILTER_PAGE_COUNT
Commit 4b59e6c473 ("mm, show_mem: suppress page counts in
non-blockable contexts") introduced SHOW_MEM_FILTER_PAGE_COUNT to
suppress PFN walks on large memory machines.  Commit c78e93630d ("mm:
do not walk all of system memory during show_mem") avoided a PFN walk in
the generic show_mem helper which removes the requirement for
SHOW_MEM_FILTER_PAGE_COUNT in that case.

This patch removes PFN walkers from the arch-specific implementations
that report on a per-node or per-zone granularity.  ARM and unicore32
still do a PFN walk as they report memory usage on each bank which is a
much finer granularity where the debugging information may still be of
use.  As the remaining arches doing PFN walks have relatively small
amounts of memory, this patch simply removes SHOW_MEM_FILTER_PAGE_COUNT.

[akpm@linux-foundation.org: fix parisc]
Signed-off-by: Mel Gorman <mgorman@suse.de>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: James Bottomley <jejb@parisc-linux.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:44 -08:00
Jianyu Zhan
ece86e222d mm/vmalloc: interchage the implementation of vmalloc_to_{pfn,page}
Currently we are implementing vmalloc_to_pfn() as a wrapper around
vmalloc_to_page(), which is implemented as follow:

 1. walks the page talbes to generates the corresponding pfn,
 2. then converts the pfn to struct page,
 3. returns it.

And vmalloc_to_pfn() re-wraps vmalloc_to_page() to get the pfn.

This seems too circuitous, so this patch reverses the way: implement
vmalloc_to_page() as a wrapper around vmalloc_to_pfn().  This makes
vmalloc_to_pfn() and vmalloc_to_page() slightly more efficient.

No functional change.

Signed-off-by: Jianyu Zhan <nasa4836@gmail.com>
Cc: Vladimir Murzin <murzin.v@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:44 -08:00
David Rientjes
d80be7c751 mm, mempolicy: remove unneeded functions for UMA configs
Mempolicies only exist for CONFIG_NUMA configurations.  Therefore, a
certain class of functions are unneeded in configurations where
CONFIG_NUMA is disabled such as functions that duplicate existing
mempolicies, lookup existing policies, set certain mempolicy traits, or
test mempolicies for certain attributes.

Remove the unneeded functions so that any future callers get a compile-
time error and protect their code with CONFIG_NUMA as required.

Signed-off-by: David Rientjes <rientjes@google.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:44 -08:00
Andreas Sandberg
e8569dd299 mm/hugetlb.c: call MMU notifiers when copying a hugetlb page range
When copy_hugetlb_page_range() is called to copy a range of hugetlb
mappings, the secondary MMUs are not notified if there is a protection
downgrade, which breaks COW semantics in KVM.

This patch adds the necessary MMU notifier calls.

Signed-off-by: Andreas Sandberg <andreas@sandberg.pp.se>
Acked-by: Steve Capper <steve.capper@linaro.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:44 -08:00
Zhi Yong Wu
549543dff7 mm, memory-failure: fix typo in me_pagecache_dirty()
[akpm@linux-foundation.org: s/cache/pagecache/]
Signed-off-by: Zhi Yong Wu <wuzhy@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:44 -08:00
Kirill A. Shutemov
b35f1819ac mm: create a separate slab for page->ptl allocation
If DEBUG_SPINLOCK and DEBUG_LOCK_ALLOC are enabled spinlock_t on x86_64
is 72 bytes.  For page->ptl they will be allocated from kmalloc-96 slab,
so we loose 24 on each.  An average system can easily allocate few tens
thousands of page->ptl and overhead is significant.

Let's create a separate slab for page->ptl allocation to solve this.

To make sure that it really works this time, some numbers from my test
machine (just booted, no load):

Before:
  # grep '^\(kmalloc-96\|page->ptl\)' /proc/slabinfo
  kmalloc-96         31987  32190    128   30    1 : tunables  120   60    8 : slabdata   1073   1073     92
After:
  # grep '^\(kmalloc-96\|page->ptl\)' /proc/slabinfo
  page->ptl          27516  28143     72   53    1 : tunables  120   60    8 : slabdata    531    531      9
  kmalloc-96          3853   5280    128   30    1 : tunables  120   60    8 : slabdata    176    176      0

Note that the patch is useful not only for debug case, but also for
PREEMPT_RT, where spinlock_t is always bloated.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:44 -08:00
Yasuaki Ishimatsu
943dca1a1f mm: get rid of unnecessary pageblock scanning in setup_zone_migrate_reserve
Yasuaki Ishimatsu reported memory hot-add spent more than 5 _hours_ on
9TB memory machine since onlining memory sections is too slow.  And we
found out setup_zone_migrate_reserve spent >90% of the time.

The problem is, setup_zone_migrate_reserve scans all pageblocks
unconditionally, but it is only necessary if the number of reserved
block was reduced (i.e.  memory hot remove).

Moreover, maximum MIGRATE_RESERVE per zone is currently 2.  It means
that the number of reserved pageblocks is almost always unchanged.

This patch adds zone->nr_migrate_reserve_block to maintain the number of
MIGRATE_RESERVE pageblocks and it reduces the overhead of
setup_zone_migrate_reserve dramatically.  The following table shows time
of onlining a memory section.

  Amount of memory     | 128GB | 192GB | 256GB|
  ---------------------------------------------
  linux-3.12           |  23.9 |  31.4 | 44.5 |
  This patch           |   8.3 |   8.3 |  8.6 |
  Mel's proposal patch |  10.9 |  19.2 | 31.3 |
  ---------------------------------------------
                                   (millisecond)

  128GB : 4 nodes and each node has 32GB of memory
  192GB : 6 nodes and each node has 32GB of memory
  256GB : 8 nodes and each node has 32GB of memory

  (*1) Mel proposed his idea by the following threads.
       https://lkml.org/lkml/2013/10/30/272

[akpm@linux-foundation.org: tweak comment]
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Reported-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Tested-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Mel Gorman <mgorman@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:43 -08:00
Rik van Riel
34e431b0ae /proc/meminfo: provide estimated available memory
Many load balancing and workload placing programs check /proc/meminfo to
estimate how much free memory is available.  They generally do this by
adding up "free" and "cached", which was fine ten years ago, but is
pretty much guaranteed to be wrong today.

It is wrong because Cached includes memory that is not freeable as page
cache, for example shared memory segments, tmpfs, and ramfs, and it does
not include reclaimable slab memory, which can take up a large fraction
of system memory on mostly idle systems with lots of files.

Currently, the amount of memory that is available for a new workload,
without pushing the system into swap, can be estimated from MemFree,
Active(file), Inactive(file), and SReclaimable, as well as the "low"
watermarks from /proc/zoneinfo.

However, this may change in the future, and user space really should not
be expected to know kernel internals to come up with an estimate for the
amount of free memory.

It is more convenient to provide such an estimate in /proc/meminfo.  If
things change in the future, we only have to change it in one place.

Signed-off-by: Rik van Riel <riel@redhat.com>
Reported-by: Erik Mouw <erik.mouw_2@nxp.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:43 -08:00
Oleg Nesterov
5eaf1a9e23 mm: thp: turn compound_head() into BUG_ON(!PageTail) in get_huge_page_tail()
get_huge_page_tail()->compound_head() looks confusing.  Every caller
must check PageTail(page), otherwise atomic_inc(&page->_mapcount) is
simply wrong if this page is compound-trans-head.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Dave Jones <davej@redhat.com>
Cc: Darren Hart <dvhart@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mel Gorman <mgorman@suse.de>
Acked-by: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:43 -08:00
Oleg Nesterov
c728852f5d mm: thp: __get_page_tail_foll() can use get_huge_page_tail()
Cleanup. Change __get_page_tail_foll() to use get_huge_page_tail()
to avoid the code duplication.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Dave Jones <davej@redhat.com>
Cc: Darren Hart <dvhart@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mel Gorman <mgorman@suse.de>
Acked-by: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:43 -08:00
Andrea Arcangeli
9b7ac26018 mm/hugetlb.c: defer PageHeadHuge() symbol export
No actual need of it. So keep it internal.

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Khalid Aziz <khalid.aziz@oracle.com>
Cc: Pravin Shelar <pshelar@nicira.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ben Hutchings <bhutchings@solarflare.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Johannes Weiner <jweiner@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:43 -08:00
Andrew Morton
26296ad2df mm/swap.c: reorganize put_compound_page()
Tweak it so save a tab stop, make code layout slightly less nutty.

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Khalid Aziz <khalid.aziz@oracle.com>
Cc: Pravin Shelar <pshelar@nicira.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ben Hutchings <bhutchings@solarflare.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Johannes Weiner <jweiner@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:43 -08:00
Andrew Morton
758f66a29c mm/hugetlb.c: simplify PageHeadHuge() and PageHuge()
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Khalid Aziz <khalid.aziz@oracle.com>
Cc: Pravin Shelar <pshelar@nicira.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ben Hutchings <bhutchings@solarflare.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Johannes Weiner <jweiner@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:43 -08:00
Andrea Arcangeli
3bfcd13ec0 mm: hugetlbfs: use __compound_tail_refcounted in __get_page_tail too
Also remove hugetlb.h which isn't needed anymore as PageHeadHuge is
handled in mm.h.

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Khalid Aziz <khalid.aziz@oracle.com>
Cc: Pravin Shelar <pshelar@nicira.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ben Hutchings <bhutchings@solarflare.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Johannes Weiner <jweiner@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:43 -08:00
Andrea Arcangeli
44518d2b32 mm: tail page refcounting optimization for slab and hugetlbfs
This skips the _mapcount mangling for slab and hugetlbfs pages.

The main trouble in doing this is to guarantee that PageSlab and
PageHeadHuge remains constant for all get_page/put_page run on the tail
of slab or hugetlbfs compound pages.  Otherwise if they're set during
get_page but not set during put_page, the _mapcount of the tail page
would underflow.

PageHeadHuge will remain true until the compound page is released and
enters the buddy allocator so it won't risk to change even if the tail
page is the last reference left on the page.

PG_slab instead is cleared before the slab frees the head page with
put_page, so if the tail pin is released after the slab freed the page,
we would have a problem.  But in the slab case the tail pin cannot be
the last reference left on the page.  This is because the slab code is
free to reuse the compound page after a kfree/kmem_cache_free without
having to check if there's any tail pin left.  In turn all tail pins
must be always released while the head is still pinned by the slab code
and so we know PG_slab will be still set too.

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Reviewed-by: Khalid Aziz <khalid.aziz@oracle.com>
Cc: Pravin Shelar <pshelar@nicira.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ben Hutchings <bhutchings@solarflare.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Johannes Weiner <jweiner@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:43 -08:00
Andrea Arcangeli
ca641514f4 mm: thp: optimize compound_trans_huge
Currently we don't clobber page_tail->first_page during split_huge_page,
so compound_trans_head can be set to compound_head without adverse
effects, and this mostly optimizes away a smp_rmb.

It looks worthwhile to keep around the implementation that doesn't relay
on page_tail->first_page not to be clobbered, because it would be
necessary if we'll decide to enforce page->private to zero at all times
whenever PG_private is not set, also for anonymous pages.  For anonymous
pages enforcing such an invariant doesn't matter as anonymous pages
don't use page->private so we can get away with this microoptimization.

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Khalid Aziz <khalid.aziz@oracle.com>
Cc: Pravin Shelar <pshelar@nicira.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ben Hutchings <bhutchings@solarflare.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Johannes Weiner <jweiner@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:43 -08:00
Andrea Arcangeli
ebf360f9bb mm: hugetlbfs: move the put/get_page slab and hugetlbfs optimization in a faster path
We don't actually need a reference on the head page in the slab and
hugetlbfs paths, as long as we add a smp_rmb() which should be faster
than get_page_unless_zero.

[akpm@linux-foundation.org: fix typo in comment]
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Khalid Aziz <khalid.aziz@oracle.com>
Cc: Pravin Shelar <pshelar@nicira.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ben Hutchings <bhutchings@solarflare.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Johannes Weiner <jweiner@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:43 -08:00
Andrea Arcangeli
a0368d4e48 mm: hugetlb: use get_page_foll() in follow_hugetlb_page()
get_page_foll() is more optimal and is always safe to use under the PT
lock.  More so for hugetlbfs as there's no risk of race conditions with
split_huge_page regardless of the PT lock.

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Tested-by: Khalid Aziz <khalid.aziz@oracle.com>
Cc: Pravin Shelar <pshelar@nicira.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ben Hutchings <bhutchings@solarflare.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Johannes Weiner <jweiner@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:43 -08:00
Dave Hansen
0e147aed4c mm: hugetlbfs: Add some VM_BUG_ON()s to catch non-hugetlbfs pages
Dave Jiang reported that he was seeing oopses when running NUMA systems
and default_hugepagesz=1G.  I traced the issue down to
migrate_page_copy() trying to use the same code for hugetlb pages and
transparent hugepages.  It should not have been trying to pass thp pages
in there.

So, add some VM_BUG_ON()s for the next hapless VM developer that tries
the same thing.

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Tested-by: Dave Jiang <dave.jiang@intel.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:43 -08:00
Geert Uytterhoeven
f92f455f67 mm: Make {,set}page_address() static inline if WANT_PAGE_VIRTUAL
{,set}page_address() are macros if WANT_PAGE_VIRTUAL.  If
!WANT_PAGE_VIRTUAL, they're plain C functions.

If someone calls them with a void *, this pointer is auto-converted to
struct page * if !WANT_PAGE_VIRTUAL, but causes a build failure on
architectures using WANT_PAGE_VIRTUAL (arc, m68k and sparc64):

  drivers/md/bcache/bset.c: In function `__btree_sort':
  drivers/md/bcache/bset.c:1190: warning: dereferencing `void *' pointer
  drivers/md/bcache/bset.c:1190: error: request for member `virtual' in something not a structure or union

Convert them to static inline functions to fix this.  There are already
plenty of users of struct page members inside <linux/mm.h>, so there's
no reason to keep them as macros.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:43 -08:00
Paul Gortmaker
af52b040eb fs/ramfs: don't use module_init for non-modular core code
The ramfs is always built in.  It will never be modular, so using
module_init as an alias for __initcall is rather misleading.

Fix this up now, so that we can relocate module_init from init.h into
module.h in the future.  If we don't do this, we'd have to add module.h
to obviously non-modular code, and that would be a worse thing.

Note that direct use of __initcall is discouraged, vs.  one of the
priority categorized subgroups.  As __initcall gets mapped onto
device_initcall, our use of fs_initcall (which makes sense for fs code)
will thus change this registration from level 6-device to level 5-fs
(i.e. slightly earlier).  However no observable impact of that small
difference has been observed during testing, or is expected.

Also note that this change uncovers a missing semicolon bug in the
registration of the initcall.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:42 -08:00
Vladimir Davydov
b5bd856a0c fs/super.c: fix WARN on alloc_super() fail path
On fail path alloc_super() calls destroy_super(), which issues a warning
if the sb's s_mounts list is not empty, in particular if it has not been
initialized.  That said s_mounts must be initialized in alloc_super()
before any possible failure, but currently it is initialized close to
the end of the function leading to a useless warning dumped to log if
either percpu_counter_init() or list_lru_init() fails.  Let's fix this.

Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:42 -08:00
Corey Minyard
4e4f9e66a7 fs/read_write.c:compat_readv(): remove bogus area verify
The compat_do_readv_writev() function was doing a verify_area on the
incoming iov, but the nr_segs value is not checked.  If someone passes
in a -1 for nr_segs, for instance, the function should return an EINVAL.
However, it returns a EFAULT because the verify_area fails because it is
checking an array of size MAX_UINT.  The check is bogus, anyway, because
the next check, compat_rw_copy_check_uvector(), will do all the
necessary checking, anyway.  The non-compat do_readv_writev() function
doesn't do this check, so I think it's safe to just remove the code.

Signed-off-by: Corey Minyard <cminyard@mvista.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:42 -08:00
Dan Carpenter
38316c8ab7 fs/compat_ioctl.c: fix an underflow issue (harmless)
We cap "nmsgs" at I2C_RDRW_IOCTL_MAX_MSGS (42) but the current code
allows negative values.  It's harmless but it makes my static checker
upset so I've made nsmgs unsigned.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:42 -08:00
Andrew Morton
0afaa12047 posix_acl: uninlining
Uninline vast tracts of nested inline functions in
include/linux/posix_acl.h.

This reduces the text+data+bss size of x86_64 allyesconfig vmlinux by
8026 bytes.

The patch also regularises the positioning of the EXPORT_SYMBOLs in
posix_acl.c.

Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: J. Bruce Fields <bfields@fieldses.org>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Tested-by: Benny Halevy <bhalevy@primarydata.com>
Cc: Benny Halevy <bhalevy@panasas.com>
Cc: Andreas Gruenbacher <agruen@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:42 -08:00
Wanlong Gao
53a52f17d9 arch/sh/kernel/kgdb.c: add missing #include <linux/sched.h>
arch/sh/kernel/kgdb.c: In function 'sleeping_thread_to_gdb_regs':
  arch/sh/kernel/kgdb.c:225:32: error: implicit declaration of function 'task_stack_page' [-Werror=implicit-function-declaration]
  arch/sh/kernel/kgdb.c:242:23: error: dereferencing pointer to incomplete type
  arch/sh/kernel/kgdb.c:243:22: error: dereferencing pointer to incomplete type
  arch/sh/kernel/kgdb.c: In function 'singlestep_trap_handler':
  arch/sh/kernel/kgdb.c:310:27: error: 'SIGTRAP' undeclared (first use in this function)
  arch/sh/kernel/kgdb.c:310:27: note: each undeclared identifier is reported only once for each function it appears in

This was introduced by commit 16559ae48c ("kgdb: remove #include
<linux/serial_8250.h> from kgdb.h").

[geert@linux-m68k.org: reworded and reformatted]
Signed-off-by: Wanlong Gao <gaowanlong@cn.fujitsu.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@linux-m68k.org>
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:42 -08:00
Yiwen Jiang
75f82eaa50 ocfs2: fix NULL pointer dereference when dismount and ocfs2rec simultaneously
2 nodes cluster, say Node A and Node B, mount the same ocfs2 volume, and
create a file 1.

Node A			Node B
open 1, get open lock
                        rm 1, and then add 1 to orphan_dir
storage link down,
o2hb_write_timeout
->o2quo_disk_timeout
->emergency_restart
                        at the moment, Node B dismount and do
			ocfs2rec simultaneously
                        1) ocfs2_dismount_volume
			->ocfs2_recovery_exit
			->wait_event(osb->recovery_event)
			->flush_workqueue(ocfs2_wq)
			2) ocfs2rec
			->queue_work(&journal->j_recovery_work)
                        ->ocfs2_recover_orphans
			->ocfs2_commit_truncate
                        ->queue_delayed_work(&osb->osb_truncate_log_wq)

In ocfs2_recovery_exit, it flushes workqueue and then releases system
inodes.  When doing ocfs2rec, it will call ocfs2_flush_truncate_log
which will try to get sys_root_inode, and NULL pointer dereference
occurs.

Signed-off-by: Yiwen Jiang <jiangyiwen@huawei.com>
Signed-off-by: joyce <xuejiufei@huawei.com>
Signed-off-by: Joseph Qi <joseph.qi@huawei.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:42 -08:00
Tariq Saeed
a2a3b39824 ocfs2: punch hole should return EINVAL if the length argument in ioctl is negative
An unreserve space ioctl OCFS2_IOC_UNRESVSP/64 should reject a negative
length.

Orabug:14789508

Signed-off-by: Tariq Saseed <tariq.x.saeed@oracle.com>
Signed-off-by: Srinivas Eeda <srinivas.eeda@oracle.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:42 -08:00
Wei Yongjun
16eac4be46 ocfs2: fix sparse non static symbol warning
Fixes the following sparse warning:

  fs/ocfs2/stack_user.c:930:32: warning:
   symbol 'ocfs2_ls_ops' was not declared. Should it be static?

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:42 -08:00
Jie Liu
1ba2212bb3 ocfs2: adjust minlen with discard_granularity in the FITRIM ioctl
Adjust minlen with discard_granularity for FITRIM ioctl(2) if the given
minimum size in bytes is less than it because, discard granularity is
used to tell us that the minimum size of extent that can be discarded by
the storage device.

This is inspired by ext4 commit 5c2ed62fd4 ("ext4: Adjust minlen with
discard_granularity in the FITRIM ioctl") from Lukas Czerner.

Signed-off-by: Jie Liu <jeff.liu@oracle.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:42 -08:00
Jie Liu
aa89762c54 ocfs2: return EINVAL if the given range to discard is less than block size
For FITRIM ioctl(2), we should not keep silence if the given range
length ls less than a block size as there is no data blocks would be
discareded.  Hence it should return EINVAL instead.  This issue can be
verified via xfstests/generic/288 which is used for FITRIM argument
handling tests.

Signed-off-by: Jie Liu <jeff.liu@oracle.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:42 -08:00
Jie Liu
19e8ac2721 ocfs2: return EOPNOTSUPP if the device does not support discard
For FITRIM ioctl(2), we should return EOPNOTSUPP to inform the user that
the storage device does not support discard if it is, otherwise return
success would confuse the user even though there is no free blocks were
trimmed at all.

Signed-off-by: Jie Liu <jeff.liu@oracle.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:42 -08:00
Younger Liu
0a2fcd8988 ocfs2: remove redundant ocfs2_alloc_dinode_update_counts() and ocfs2_block_group_set_bits()
ocfs2_alloc_dinode_update_counts() and ocfs2_block_group_set_bits() are
already provided in suballoc.c.  So, the same functions in
move_extents.c are not needed any more.

Declare the functions in suballoc.h and remove redundant functions in
move_extents.c.

Signed-off-by: Younger Liu <liuyiyang@hisense.com>
Cc: Younger Liu <younger.liucn@gmail.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:42 -08:00
Goldwyn Rodrigues
c994c2ebdb ocfs2: use the new DLM operation callbacks while requesting new lockspace
Attempt to use the new DLM operations.  If it is not supported, use the
traditional ocfs2_controld.

To exchange ocfs2 versioning, we use the LVB of the version dlm lock.
It first attempts to take the lock in EX mode (non-blocking).  If
successful (which means it is the first mount), it writes the version
number and downconverts to PR lock.  If it is unsuccessful, it reads the
version from the lock.

If this becomes the standard (with o2cb as well), it could simplify
userspace tools to check if the filesystem is mounted on other nodes.

Dan: Since ocfs2_protocol_version are two u8 values, the additional
checks with LONG* don't make sense.

Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:42 -08:00
Goldwyn Rodrigues
4150363033 ocfs2: framework for version LVB
Use the native DLM locks for version control negotiation.  Most of the
framework is taken from gfs2/lock_dlm.c

Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Reviewed-by: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:41 -08:00
Goldwyn Rodrigues
3e83415164 ocfs2: pass ocfs2_cluster_connection to ocfs2_this_node
This is done to differentiate between using and not using controld and
use the connection information accordingly.

We need to be backward compatible.  So, we use a new enum
ocfs2_connection_type to identify when controld is used and when it is
not.

Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Reviewed-by: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:41 -08:00
Goldwyn Rodrigues
24aa338611 ocfs2: shift allocation ocfs2_live_connection to user_connect()
We perform this because the DLM recovery callbacks will require the
ocfs2_live_connection structure to record the node information when
dlm_new_lockspace() is updated (in the last patch of the series).

Before calling dlm_new_lockspace(), we need the structure ready for the
.recover_done() callback, which would set oc_this_node.  This is the
reason we allocate ocfs2_live_connection beforehand in user_connect().

[AKPM] rc initialization is not required because it assigned in case of
errors.  It will be cleared by compiler anyways.

Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Reveiwed-by: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:41 -08:00
Goldwyn Rodrigues
66e188fc31 ocfs2: add DLM recovery callbacks
These are the callbacks called by the fs/dlm code in case the membership
changes.  If there is a failure while/during calling any of these, the
DLM creates a new membership and relays to the rest of the nodes.

 - recover_prep() is called when DLM understands a node is down.
 - recover_slot() is called once all nodes have acknowledged
   recover_prep and recovery can begin.
 - recover_done() is called once the recovery is complete.  It returns
   the new membership.

Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Reviewed-by: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:41 -08:00
Goldwyn Rodrigues
c74a3bdd9b ocfs2: add clustername to cluster connection
This is an effort of removing ocfs2_controld.pcmk and getting ocfs2 DLM
handling up to the times with respect to DLM (>=4.0.1) and corosync
(2.3.x).  AFAIK, cman also is being phased out for a unified corosync
cluster stack.

fs/dlm performs all the functions with respect to fencing and node
management and provides the API's to do so for ocfs2.  For all future
references, DLM stands for fs/dlm code.

The advantages are:
 + No need to run an additional userspace daemon (ocfs2_controld)
 + No controld device handling and controld protocol
 + Shifting responsibilities of node management to DLM layer

For backward compatibility, we are keeping the controld handling code.
Once enough time has passed we can remove a significant portion of the
code.  This was tested by using the kernel with changes on older
unmodified tools.  The kernel used ocfs2_controld as expected, and
displayed the appropriate warning message.

This feature requires modification in the userspace ocfs2-tools.  The
changes can be found at: https://github.com/goldwynr/ocfs2-tools branch:
nocontrold Currently, not many checks are present in the userspace code,
but that would change soon.

This patch (of 6):

Add clustername to cluster connection.

Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Reviewed-by: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:41 -08:00
Goldwyn Rodrigues
ff8fb33522 ocfs2: remove versioning information
The versioning information is confusing for end-users.  The numbers are
stuck at 1.5.0 when the tools version have moved to 1.8.2.  Remove the
versioning system in the OCFS2 modules and let the kernel version be the
guide to debug issues.

Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Acked-by: Sunil Mushran <sunil.mushran@gmail.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Acked-by: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:41 -08:00
Geert Uytterhoeven
227d006628 score: remove "select HAVE_GENERIC_HARDIRQS" again
Commit 5fbbf8a1a9 ("Score: The commit is for compiling successfully.")
re-introduced "select HAVE_GENERIC_HARDIRQS" in v3.12-rc4, which had
just been removed in v3.12-rc1 by 0244ad004a ("Remove GENERIC_HARDIRQ
config option").

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Chen Liqin <liqin.linux@gmail.com>
Cc: Lennox Wu <lennox.wu@gmail.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:41 -08:00
Alex Williamson
08336fd218 intel-iommu: fix off-by-one in pagetable freeing
dma_pte_free_level() has an off-by-one error when checking whether a pte
is completely covered by a range.  Take for example the case of
attempting to free pfn 0x0 - 0x1ff, ie.  512 entries covering the first
2M superpage.

The level_size() is 0x200 and we test:

  static void dma_pte_free_level(...
	...

	if (!(0 > 0 || 0x1ff < 0 + 0x200)) {
		...
	}

Clearly the 2nd test is true, which means we fail to take the branch to
clear and free the pagetable entry.  As a result, we're leaking
pagetables and failing to install new pages over the range.

This was found with a PCI device assigned to a QEMU guest using vfio-pci
without a VGA device present.  The first 1M of guest address space is
mapped with various combinations of 4K pages, but eventually the range
is entirely freed and replaced with a 2M contiguous mapping.
intel-iommu errors out with something like:

  ERROR: DMA PTE for vPFN 0x0 already set (to 5c2b8003 not 849c00083)

In this case 5c2b8003 is the pointer to the previous leaf page that was
neither freed nor cleared and 849c00083 is the superpage entry that
we're trying to replace it with.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:41 -08:00
Jan Kara
56b27cf603 fsnotify: remove pointless NULL initializers
We usually rely on the fact that struct members not specified in the
initializer are set to NULL.  So do that with fsnotify function pointers
as well.

Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Eric Paris <eparis@parisplace.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:41 -08:00
Jan Kara
83c4c4b0a3 fsnotify: remove .should_send_event callback
After removing event structure creation from the generic layer there is
no reason for separate .should_send_event and .handle_event callbacks.
So just remove the first one.

Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Eric Paris <eparis@parisplace.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:41 -08:00
Jan Kara
7053aee26a fsnotify: do not share events between notification groups
Currently fsnotify framework creates one event structure for each
notification event and links this event into all interested notification
groups.  This is done so that we save memory when several notification
groups are interested in the event.  However the need for event
structure shared between inotify & fanotify bloats the event structure
so the result is often higher memory consumption.

Another problem is that fsnotify framework keeps path references with
outstanding events so that fanotify can return open file descriptors
with its events.  This has the undesirable effect that filesystem cannot
be unmounted while there are outstanding events - a regression for
inotify compared to a situation before it was converted to fsnotify
framework.  For fanotify this problem is hard to avoid and users of
fanotify should kind of expect this behavior when they ask for file
descriptors from notified files.

This patch changes fsnotify and its users to create separate event
structure for each group.  This allows for much simpler code (~400 lines
removed by this patch) and also smaller event structures.  For example
on 64-bit system original struct fsnotify_event consumes 120 bytes, plus
additional space for file name, additional 24 bytes for second and each
subsequent group linking the event, and additional 32 bytes for each
inotify group for private data.  After the conversion inotify event
consumes 48 bytes plus space for file name which is considerably less
memory unless file names are long and there are several groups
interested in the events (both of which are uncommon).  Fanotify event
fits in 56 bytes after the conversion (fanotify doesn't care about file
names so its events don't have to have it allocated).  A win unless
there are four or more fanotify groups interested in the event.

The conversion also solves the problem with unmount when only inotify is
used as we don't have to grab path references for inotify events.

[hughd@google.com: fanotify: fix corruption preventing startup]
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Eric Paris <eparis@parisplace.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:41 -08:00
Jan Kara
e9fe69045b inotify: provide function for name length rounding
Rounding of name length when passing it to userspace was done in several
places.  Provide a function to do it and use it in all places.

Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Eric Paris <eparis@parisplace.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:41 -08:00
Dan Williams
0abdd7a81b dma-debug: introduce debug_dma_assert_idle()
Record actively mapped pages and provide an api for asserting a given
page is dma inactive before execution proceeds.  Placing
debug_dma_assert_idle() in cow_user_page() flagged the violation of the
dma-api in the NET_DMA implementation (see commit 7787380336 "net_dma:
mark broken").

The implementation includes the capability to count, in a limited way,
repeat mappings of the same page that occur without an intervening
unmap.  This 'overlap' counter is limited to the few bits of tag space
in a radix tree.  This mechanism is added to mitigate false negative
cases where, for example, a page is dma mapped twice and
debug_dma_assert_idle() is called after the page is un-mapped once.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: James Bottomley <JBottomley@Parallels.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:41 -08:00