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307284 commits

Author SHA1 Message Date
Sujit Reddy Thumma
c2cd220c90 cfq-iosched: Fix null pointer dereference
NULL pointer dereference can happen in cfq_choose_cfqg()
when there are no cfq groups to select other than the
current serving group. Prevent this by adding a NULL
check before dereferencing.

Unable to handle kernel NULL pointer dereference at virtual address
[<c02502cc>] (cfq_dispatch_requests+0x368/0x8c0) from
[<c0243f30>] (blk_peek_request+0x220/0x25c)
[<c0243f30>] (blk_peek_request+0x220/0x25c) from
[<c0243f74>] (blk_fetch_request+0x8/0x1c)
[<c0243f74>] (blk_fetch_request+0x8/0x1c) from
[<c041cedc>] (mmc_queue_thread+0x58/0x120)
[<c041cedc>] (mmc_queue_thread+0x58/0x120) from
[<c00ad310>] (kthread+0x84/0x90)
[<c00ad310>] (kthread+0x84/0x90) from
[<c000eeac>] (kernel_thread_exit+0x0/0x8)

CRs-Fixed: 416466
Change-Id: I1fab93a4334b53e1d7c5dcc8f93cff174bae0d5e
Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>
2016-10-29 23:12:34 +08:00
Krishna Chaitanya Parimi
7c6ed19d8f msm: msm_fb: validating backlight level and scale value
Validating the value of backlight to be not more than the
max value and also ensuring that the backlight scale value
is not more than 1024, thereby ensuring that backlight
scaling factor is not more than 1

Change-Id: I6a6f4f0f0a8c272edcac5078276fb406ddee3e90
Signed-off-by: Krishna Chaitanya Parimi <cparimi@codeaurora.org>
[zhaoweiliew: Add bl_lvl argument for msm_fb_scale_bl in bl_workqueue_handler]
Signed-off-by: Zhao Wei Liew <zhaoweiliew@gmail.com>
2016-10-29 23:12:34 +08:00
Krishna Chaitanya Parimi
5fab4dda1c msm: fb: Null check mfd data
Add appropriate null check for mfd data
structure before accessing it's members.
This prevents null pointer accesses in
the driver.

Change-Id: I5aae937f839e4f6ed8d5c5a4b54ab45f0ff07332
Signed-off-by: Krishna Chaitanya Parimi <cparimi@codeaurora.org>
2016-10-29 23:12:34 +08:00
Daniel Borkmann
102d68ebe7 net: inet_diag: zero out uninitialized idiag_{src,dst} fields
Jakub reported while working with nlmon netlink sniffer that parts of
the inet_diag_sockid are not initialized when r->idiag_family != AF_INET6.
That is, fields of r->id.idiag_src[1 ... 3], r->id.idiag_dst[1 ... 3].

In fact, it seems that we can leak 6 * sizeof(u32) byte of kernel [slab]
memory through this. At least, in udp_dump_one(), we allocate a skb in ...

  rep = nlmsg_new(sizeof(struct inet_diag_msg) + ..., GFP_KERNEL);

... and then pass that to inet_sk_diag_fill() that puts the whole struct
inet_diag_msg into the skb, where we only fill out r->id.idiag_src[0],
r->id.idiag_dst[0] and leave the rest untouched:

  r->id.idiag_src[0] = inet->inet_rcv_saddr;
  r->id.idiag_dst[0] = inet->inet_daddr;

struct inet_diag_msg embeds struct inet_diag_sockid that is correctly /
fully filled out in IPv6 case, but for IPv4 not.

So just zero them out by using plain memset (for this little amount of
bytes it's probably not worth the extra check for idiag_family == AF_INET).

Similarly, fix also other places where we fill that out.

[Upstream commit b1aac815c0]

Change-Id: Ief40178e5bc9b4e9c207607e4c05970371d1e6f8
Reported-by: Jakub Zawadzki <darkjames-ws@darkjames.pl>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Lorenzo Colitti <lorenzo@google.com>
2016-10-29 23:12:34 +08:00
Theodore Ts'o
2da70f4e34 ext4: avoid hang when mounting non-journal filesystems with orphan list
When trying to mount a file system which does not contain a journal,
but which does have a orphan list containing an inode which needs to
be truncated, the mount call with hang forever in
ext4_orphan_cleanup() because ext4_orphan_del() will return
immediately without removing the inode from the orphan list, leading
to an uninterruptible loop in kernel code which will busy out one of
the CPU's on the system.

This can be trivially reproduced by trying to mount the file system
found in tests/f_orphan_extents_inode/image.gz from the e2fsprogs
source tree.  If a malicious user were to put this on a USB stick, and
mount it on a Linux desktop which has automatic mounts enabled, this
could be considered a potential denial of service attack.  (Not a big
deal in practice, but professional paranoids worry about such things,
and have even been known to allocate CVE numbers for such problems.)

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Zheng Liu <wenqing.lz@taobao.com>
Cc: stable@vger.kernel.org
2016-10-29 23:12:34 +08:00
Anatol Pomozov
012f862b13 ext4: make orphan functions be no-op in no-journal mode
Instead of checking whether the handle is valid, we check if journal
is enabled. This avoids taking the s_orphan_lock mutex in all cases
when there is no journal in use, including the error paths where
ext4_orphan_del() is called with a handle set to NULL.

Signed-off-by: Anatol Pomozov <anatol.pomozov@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2016-10-29 23:12:34 +08:00
Siddartha Mohanadoss
be59a66ad1 hwmon: epm_adc: Fix potential dereference
Update epm_adc_psoc_show_in() to fix potential
dereference to adc_code used to store the
PSOC code data.

Change-Id: I7b68f50f89fd38f0ac32f1793720e1af3ef43022
Signed-off-by: Siddartha Mohanadoss <smohanad@codeaurora.org>
2016-10-29 23:12:34 +08:00
Binoy Jayan
bc64aa3603 char: Fix NULL pointer dereferences
Fix the following NULL pointer dereferences in character drivers.

Null pointer 'pra' that comes from line 825 may be passed to function
and can be dereferenced there by passing argument 4 to function
'fastrpc_internal_invoke' at line 847.
drivers/char/adsprpc.c +847 | fastrpc_device_ioctl()

Null pointer 'rpra' that comes from line 672 may be passed
to function and can be dereferenced there by passing argument 2
to function 'inv_args' at line 702.
drivers/char/adsprpc.c +702 | fastrpc_internal_invoke()

Constant NULL may be dereferenced by passing argument 3 to
function 'diag_device_write' at line 165.
drivers/char/diag/diagfwd_hsic.c +165 | diag_hsic_read_complete_callback()
drivers/char/diag/diagfwd.c +585 | diag_device_write()

Change-Id: I30469575c30f3846b449b6c71522f7dfc10c5bc5
Signed-off-by: Binoy Jayan <bjayan@codeaurora.org>
2016-10-29 23:12:34 +08:00
Binoy Jayan
db7da01998 msm: iommu: Fix NULL pointer dereference
Fix the following NULL pointer dereference issue.

Pointer '__p' returned from call to function 'smem_alloc' at line 84
may be NULL and will be dereferenced at line 85.
drivers/iommu/msm_iommu.c +85 | _msm_iommu_remote_spin_lock_init()

Change-Id: I3549e8dc6cb6b13518ced7d28186da74667c1cb6
Signed-off-by: Binoy Jayan <bjayan@codeaurora.org>
2016-10-29 23:12:33 +08:00
Vinu Deokaran
9457ce78b6 gpu: ion: return error code when iommu map fails
Return correct error code to caller when __ion_iommu_map fails.

Change-Id: If18480769fc7d3567017bad586d38e1eb9e0e05f
Signed-off-by: Vinu Deokaran <vinud@codeaurora.org>
2016-10-29 23:12:33 +08:00
Swetha Chikkaboraiah
2f005d1127 msm: perf: Protect buffer overflow due to malicious user
In function krait_pmu_disable_event, parameter hwc comes from
userspace and is untrusted.The function krait_clearpmu is called
after the function get_krait_evtinfo.
Function get_krait_evtinfo as parameter krait_evt_type variable
which is used to extract the groupcode(reg) which is bound to
 KRAIT_MAX_L1_REG (is 3). After validation,one code path modifies
groupcode(reg):If this code path executes, groupcode(reg) can be
3,4, 5, or 6. In krait_clearpmu groupcode used to access array
krait_functions whose size is 3. Since groupcode can be 3,4,5,6
accessing array krait_functions lead to bufferoverlflow.
This change will validate groupcode not to exceed 3 .

Change-Id: I48c92adda137d8a074b4e1a367a468195a810ca1
CRs-fixed: 962450
Signed-off-by: Swetha Chikkaboraiah <schikk@codeaurora.org>
2016-10-29 23:12:33 +08:00
Johannes Weiner
5b0920e259 mm: vmscan: clear kswapd's special reclaim powers before exiting
commit 71abdc15ad upstream.

When kswapd exits, it can end up taking locks that were previously held
by allocating tasks while they waited for reclaim.  Lockdep currently
warns about this:

On Wed, May 28, 2014 at 06:06:34PM +0800, Gu Zheng wrote:
>  inconsistent {RECLAIM_FS-ON-W} -> {IN-RECLAIM_FS-R} usage.
>  kswapd2/1151 [HC0[0]:SC0[0]:HE1:SE1] takes:
>   (&sig->group_rwsem){+++++?}, at: exit_signals+0x24/0x130
>  {RECLAIM_FS-ON-W} state was registered at:
>     mark_held_locks+0xb9/0x140
>     lockdep_trace_alloc+0x7a/0xe0
>     kmem_cache_alloc_trace+0x37/0x240
>     flex_array_alloc+0x99/0x1a0
>     cgroup_attach_task+0x63/0x430
>     attach_task_by_pid+0x210/0x280
>     cgroup_procs_write+0x16/0x20
>     cgroup_file_write+0x120/0x2c0
>     vfs_write+0xc0/0x1f0
>     SyS_write+0x4c/0xa0
>     tracesys+0xdd/0xe2
>  irq event stamp: 49
>  hardirqs last  enabled at (49):  _raw_spin_unlock_irqrestore+0x36/0x70
>  hardirqs last disabled at (48):  _raw_spin_lock_irqsave+0x2b/0xa0
>  softirqs last  enabled at (0):  copy_process.part.24+0x627/0x15f0
>  softirqs last disabled at (0):            (null)
>
>  other info that might help us debug this:
>   Possible unsafe locking scenario:
>
>         CPU0
>         ----
>    lock(&sig->group_rwsem);
>    <Interrupt>
>      lock(&sig->group_rwsem);
>
>   *** DEADLOCK ***
>
>  no locks held by kswapd2/1151.
>
>  stack backtrace:
>  CPU: 30 PID: 1151 Comm: kswapd2 Not tainted 3.10.39+ #4
>  Call Trace:
>    dump_stack+0x19/0x1b
>    print_usage_bug+0x1f7/0x208
>    mark_lock+0x21d/0x2a0
>    __lock_acquire+0x52a/0xb60
>    lock_acquire+0xa2/0x140
>    down_read+0x51/0xa0
>    exit_signals+0x24/0x130
>    do_exit+0xb5/0xa50
>    kthread+0xdb/0x100
>    ret_from_fork+0x7c/0xb0

This is because the kswapd thread is still marked as a reclaimer at the
time of exit.  But because it is exiting, nobody is actually waiting on
it to make reclaim progress anymore, and it's nothing but a regular
thread at this point.  Be tidy and strip it of all its powers
(PF_MEMALLOC, PF_SWAPWRITE, PF_KSWAPD, and the lockdep reclaim state)
before returning from the thread function.

Change-Id: I51cc36b913919dbaeb56322d7afe71e0c36f36bc
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reported-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Tang Chen <tangchen@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-29 23:12:33 +08:00
Johannes Weiner
9cd0fcd2e1 mm: vmscan: fix endless loop in kswapd balancing
commit 60cefed485 upstream.

Kswapd does not in all places have the same criteria for a balanced
zone.  Zones are only being reclaimed when their high watermark is
breached, but compaction checks loop over the zonelist again when the
zone does not meet the low watermark plus two times the size of the
allocation.  This gets kswapd stuck in an endless loop over a small
zone, like the DMA zone, where the high watermark is smaller than the
compaction requirement.

Add a function, zone_balanced(), that checks the watermark, and, for
higher order allocations, if compaction has enough free memory.  Then
use it uniformly to check for balanced zones.

This makes sure that when the compaction watermark is not met, at least
reclaim happens and progress is made - or the zone is declared
unreclaimable at some point and skipped entirely.

Change-Id: I28fd1de8628aa7e799cbc11e313e8d8f3e2df977
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reported-by: George Spelvin <linux@horizon.com>
Reported-by: Johannes Hirte <johannes.hirte@fem.tu-ilmenau.de>
Reported-by: Tomas Racek <tracek@redhat.com>
Tested-by: Johannes Hirte <johannes.hirte@fem.tu-ilmenau.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[hq: Backported to 3.4: adjust context]
Signed-off-by: Qiang Huang <h.huangqiang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-29 23:12:33 +08:00
Takamori Yamaguchi
11dde6639f mm: bugfix: set current->reclaim_state to NULL while returning from kswapd()
commit b0a8cc58e6 upstream.

In kswapd(), set current->reclaim_state to NULL before returning, as
current->reclaim_state holds reference to variable on kswapd()'s stack.

In rare cases, while returning from kswapd() during memory offlining,
__free_slab() and freepages() can access the dangling pointer of
current->reclaim_state.

Change-Id: I49f69977895442b3a8328c9c39877369b4554ba5
Signed-off-by: Takamori Yamaguchi <takamori.yamaguchi@jp.sony.com>
Signed-off-by: Aaditya Kumar <aaditya.kumar@ap.sony.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-29 23:12:33 +08:00
Satoru Moriya
5ebc63e913 mm: avoid swapping out with swappiness==0
commit fe35004fbf upstream.

Sometimes we'd like to avoid swapping out anonymous memory.  In
particular, avoid swapping out pages of important process or process
groups while there is a reasonable amount of pagecache on RAM so that we
can satisfy our customers' requirements.

OTOH, we can control how aggressive the kernel will swap memory pages with
/proc/sys/vm/swappiness for global and
/sys/fs/cgroup/memory/memory.swappiness for each memcg.

But with current reclaim implementation, the kernel may swap out even if
we set swappiness=0 and there is pagecache in RAM.

This patch changes the behavior with swappiness==0.  If we set
swappiness==0, the kernel does not swap out completely (for global reclaim
until the amount of free pages and filebacked pages in a zone has been
reduced to something very very small (nr_free + nr_filebacked < high
watermark)).

Change-Id: Ibb357f534711e73838bca037bed7532bbf4d2728
Signed-off-by: Satoru Moriya <satoru.moriya@hds.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Reviewed-by: Rik van Riel <riel@redhat.com>
Acked-by: Jerome Marchand <jmarchan@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-29 23:12:33 +08:00
Aaditya Kumar
771a6bd113 mm: fix lost kswapd wakeup in kswapd_stop()
commit 1c7e7f6c07 upstream.

Offlining memory may block forever, waiting for kswapd() to wake up
because kswapd() does not check the event kthread->should_stop before
sleeping.

The proper pattern, from Documentation/memory-barriers.txt, is:

   ---  waker  ---
   event_indicated = 1;
   wake_up_process(event_daemon);

   ---  sleeper  ---
   for (;;) {
      set_current_state(TASK_UNINTERRUPTIBLE);
      if (event_indicated)
         break;
      schedule();
   }

   set_current_state() may be wrapped by:
      prepare_to_wait();

In the kswapd() case, event_indicated is kthread->should_stop.

  === offlining memory (waker) ===
   kswapd_stop()
      kthread_stop()
         kthread->should_stop = 1
         wake_up_process()
         wait_for_completion()

  ===  kswapd_try_to_sleep (sleeper) ===
   kswapd_try_to_sleep()
      prepare_to_wait()
           .
           .
      schedule()
           .
           .
      finish_wait()

The schedule() needs to be protected by a test of kthread->should_stop,
which is wrapped by kthread_should_stop().

Reproducer:
   Do heavy file I/O in background.
   Do a memory offline/online in a tight loop

Change-Id: I3fcff189649427eb33ebf6c8753c1fed2cf0d687
Signed-off-by: Aaditya Kumar <aaditya.kumar@ap.sony.com>
Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: Minchan Kim <minchan@kernel.org>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-29 23:12:33 +08:00
Jiang Liu
12fe62c50a memory hotplug: fix invalid memory access caused by stale kswapd pointer
commit d8adde17e5 upstream.

kswapd_stop() is called to destroy the kswapd work thread when all memory
of a NUMA node has been offlined.  But kswapd_stop() only terminates the
work thread without resetting NODE_DATA(nid)->kswapd to NULL.  The stale
pointer will prevent kswapd_run() from creating a new work thread when
adding memory to the memory-less NUMA node again.  Eventually the stale
pointer may cause invalid memory access.

An example stack dump as below. It's reproduced with 2.6.32, but latest
kernel has the same issue.

  BUG: unable to handle kernel NULL pointer dereference at (null)
  IP: [<ffffffff81051a94>] exit_creds+0x12/0x78
  PGD 0
  Oops: 0000 [#1] SMP
  last sysfs file: /sys/devices/system/memory/memory391/state
  CPU 11
  Modules linked in: cpufreq_conservative cpufreq_userspace cpufreq_powersave acpi_cpufreq microcode fuse loop dm_mod tpm_tis rtc_cmos i2c_i801 rtc_core tpm serio_raw pcspkr sg tpm_bios igb i2c_core iTCO_wdt rtc_lib mptctl iTCO_vendor_support button dca bnx2 usbhid hid uhci_hcd ehci_hcd usbcore sd_mod crc_t10dif edd ext3 mbcache jbd fan ide_pci_generic ide_core ata_generic ata_piix libata thermal processor thermal_sys hwmon mptsas mptscsih mptbase scsi_transport_sas scsi_mod
  Pid: 7949, comm: sh Not tainted 2.6.32.12-qiuxishi-5-default #92 Tecal RH2285
  RIP: 0010:exit_creds+0x12/0x78
  RSP: 0018:ffff8806044f1d78  EFLAGS: 00010202
  RAX: 0000000000000000 RBX: ffff880604f22140 RCX: 0000000000019502
  RDX: 0000000000000000 RSI: 0000000000000202 RDI: 0000000000000000
  RBP: ffff880604f22150 R08: 0000000000000000 R09: ffffffff81a4dc10
  R10: 00000000000032a0 R11: ffff880006202500 R12: 0000000000000000
  R13: 0000000000c40000 R14: 0000000000008000 R15: 0000000000000001
  FS:  00007fbc03d066f0(0000) GS:ffff8800282e0000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
  CR2: 0000000000000000 CR3: 000000060f029000 CR4: 00000000000006e0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
  Process sh (pid: 7949, threadinfo ffff8806044f0000, task ffff880603d7c600)
  Stack:
   ffff880604f22140 ffffffff8103aac5 ffff880604f22140 ffffffff8104d21e
   ffff880006202500 0000000000008000 0000000000c38000 ffffffff810bd5b1
   0000000000000000 ffff880603d7c600 00000000ffffdd29 0000000000000003
  Call Trace:
    __put_task_struct+0x5d/0x97
    kthread_stop+0x50/0x58
    offline_pages+0x324/0x3da
    memory_block_change_state+0x179/0x1db
    store_mem_state+0x9e/0xbb
    sysfs_write_file+0xd0/0x107
    vfs_write+0xad/0x169
    sys_write+0x45/0x6e
    system_call_fastpath+0x16/0x1b
  Code: ff 4d 00 0f 94 c0 84 c0 74 08 48 89 ef e8 1f fd ff ff 5b 5d 31 c0 41 5c c3 53 48 8b 87 20 06 00 00 48 89 fb 48 8b bf 18 06 00 00 <8b> 00 48 c7 83 18 06 00 00 00 00 00 00 f0 ff 0f 0f 94 c0 84 c0
  RIP  exit_creds+0x12/0x78
   RSP <ffff8806044f1d78>
  CR2: 0000000000000000

[akpm@linux-foundation.org: add pglist_data.kswapd locking comments]
Signed-off-by: Xishi Qiu <qiuxishi@huawei.com>
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Acked-by: David Rientjes <rientjes@google.com>
Reviewed-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Change-Id: I8ca11163c73636fee7d5550ddc8aaca99b4e02bf
2016-10-29 23:12:33 +08:00
Michal Hocko
90c2845054 mm: consider all swapped back pages in used-once logic
commit e48982734e upstream.

Commit 6457474624 ("vmscan: detect mapped file pages used only once")
made mapped pages have another round in inactive list because they might
be just short lived and so we could consider them again next time.  This
heuristic helps to reduce pressure on the active list with a streaming
IO worklods.

This patch fixes a regression introduced by this commit for heavy shmem
based workloads because unlike Anon pages, which are excluded from this
heuristic because they are usually long lived, shmem pages are handled
as a regular page cache.

This doesn't work quite well, unfortunately, if the workload is mostly
backed by shmem (in memory database sitting on 80% of memory) with a
streaming IO in the background (backup - up to 20% of memory).  Anon
inactive list is full of (dirty) shmem pages when watermarks are hit.
Shmem pages are kept in the inactive list (they are referenced) in the
first round and it is hard to reclaim anything else so we reach lower
scanning priorities very quickly which leads to an excessive swap out.

Let's fix this by excluding all swap backed pages (they tend to be long
lived wrt.  the regular page cache anyway) from used-once heuristic and
rather activate them if they are referenced.

The customer's workload is shmem backed database (80% of RAM) and they
are measuring transactions/s with an IO in the background (20%).
Transactions touch more or less random rows in the table.  The
transaction rate fell by a factor of 3 (in the worst case) because of
commit 64574746.  This patch restores the previous numbers.

Change-Id: Id6696030f349217d40d22cd8c17b3ffad1c4253f
Signed-off-by: Michal Hocko <mhocko@suse.cz>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Minchan Kim <minchan@kernel.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-29 23:12:33 +08:00
Sabrina Dubroca
9664667610 ipv6: clean up anycast when an interface is destroyed
If we try to rmmod the driver for an interface while sockets with
setsockopt(JOIN_ANYCAST) are alive, some refcounts aren't cleaned up
and we get stuck on:

  unregister_netdevice: waiting for ens3 to become free. Usage count = 1

If we LEAVE_ANYCAST/close everything before rmmod'ing, there is no
problem.

We need to perform a cleanup similar to the one for multicast in
addrconf_ifdown(how == 1).

BUG: 18902601
Change-Id: I6d51aed5755eb5738fcba91950e7773a1c985d2e
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

[Backported from android-3.10 86a47ad60de5221c3869821d3552dcd1c89199f5]

Signed-off-by: Lorenzo Colitti <lorenzo@google.com>
2016-10-29 23:12:33 +08:00
liping.zhang
42474a778b net: tcp: fix rtable leak in tcp_is_local[6]
ip_rt_put/ip6_rt_put call is missed after route lookup routine.
So if lookup returns ok, rtable leak will happen.

Change-Id: Ica137043879b4305b70401cf7e8efda24405e3ff
Signed-off-by: Liping Zhang <liping.zhang@spreadtrum.com>
2016-10-29 23:12:33 +08:00
David Howells
0809fed0d6 KEYS: Fix race between read and revoke
This fixes CVE-2015-7550.

There's a race between keyctl_read() and keyctl_revoke().  If the revoke
happens between keyctl_read() checking the validity of a key and the key's
semaphore being taken, then the key type read method will see a revoked key.

This causes a problem for the user-defined key type because it assumes in
its read method that there will always be a payload in a non-revoked key
and doesn't check for a NULL pointer.

Fix this by making keyctl_read() check the validity of a key after taking
semaphore instead of before.

I think the bug was introduced with the original keyrings code.

This was discovered by a multithreaded test program generated by syzkaller
(http://github.com/google/syzkaller).  Here's a cleaned up version:

	#include <sys/types.h>
	#include <keyutils.h>
	#include <pthread.h>
	void *thr0(void *arg)
	{
		key_serial_t key = (unsigned long)arg;
		keyctl_revoke(key);
		return 0;
	}
	void *thr1(void *arg)
	{
		key_serial_t key = (unsigned long)arg;
		char buffer[16];
		keyctl_read(key, buffer, 16);
		return 0;
	}
	int main()
	{
		key_serial_t key = add_key("user", "%", "foo", 3, KEY_SPEC_USER_KEYRING);
		pthread_t th[5];
		pthread_create(&th[0], 0, thr0, (void *)(unsigned long)key);
		pthread_create(&th[1], 0, thr1, (void *)(unsigned long)key);
		pthread_create(&th[2], 0, thr0, (void *)(unsigned long)key);
		pthread_create(&th[3], 0, thr1, (void *)(unsigned long)key);
		pthread_join(th[0], 0);
		pthread_join(th[1], 0);
		pthread_join(th[2], 0);
		pthread_join(th[3], 0);
		return 0;
	}

Build as:

	cc -o keyctl-race keyctl-race.c -lkeyutils -lpthread

Run as:

	while keyctl-race; do :; done

as it may need several iterations to crash the kernel.  The crash can be
summarised as:

	BUG: unable to handle kernel NULL pointer dereference at 0000000000000010
	IP: [<ffffffff81279b08>] user_read+0x56/0xa3
	...
	Call Trace:
	 [<ffffffff81276aa9>] keyctl_read_key+0xb6/0xd7
	 [<ffffffff81277815>] SyS_keyctl+0x83/0xe0
	 [<ffffffff815dbb97>] entry_SYSCALL_64_fastpath+0x12/0x6f

Change-Id: Id4a5e47860162f62c94bb66728ca9e712f9d89c2
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Dmitry Vyukov <dvyukov@google.com>
Cc: stable@vger.kernel.org
Signed-off-by: James Morris <james.l.morris@oracle.com>
2016-10-29 23:12:33 +08:00
Eric Dumazet
1d89f42bbc rcu: Fix batch-limit size problem
commit 878d7439d0 upstream.

Commit 29c00b4a1d (rcu: Add event-tracing for RCU callback
invocation) added a regression in rcu_do_batch()

Under stress, RCU is supposed to allow to process all items in queue,
instead of a batch of 10 items (blimit), but an integer overflow makes
the effective limit being 1.  So, unless there is frequent idle periods
(during which RCU ignores batch limits), RCU can be forced into a
state where it cannot keep up with the callback-generation rate,
eventually resulting in OOM.

This commit therefore converts a few variables in rcu_do_batch() from
int to long to fix this problem, along with the module parameters
controlling the batch limits.

Change-Id: I6d6dcb94d2a31f0cf00d3121a7b92e49aa7ab108
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-29 23:12:32 +08:00
Chao Yu
b86bad0997 f2fs: fix to avoid deadlock when merging inline data
When testing with fsstress, kworker and user threads were both blocked:

INFO: task kworker/u16:1:16580 blocked for more than 120 seconds.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/u16:1   D ffff8803f2595390     0 16580      2 0x00000000
Workqueue: writeback bdi_writeback_workfn (flush-251:0)
 ffff8802730e5760 0000000000000046 ffff880274729fc0 0000000000012440
 ffff8802730e5fd8 ffff8802730e4010 0000000000012440 0000000000012440
 ffff8802730e5fd8 0000000000012440 ffff880274729fc0 ffff88026eb50000
Call Trace:
 [<ffffffff816fe9d9>] schedule+0x29/0x70
 [<ffffffff816ff895>] rwsem_down_read_failed+0xa5/0xf9
 [<ffffffff81378584>] call_rwsem_down_read_failed+0x14/0x30
 [<ffffffffa0694feb>] f2fs_write_data_page+0x31b/0x420 [f2fs]
 [<ffffffffa0690f1a>] __f2fs_writepage+0x1a/0x50 [f2fs]
 [<ffffffffa06922a0>] f2fs_write_data_pages+0xe0/0x290 [f2fs]
 [<ffffffff811473b3>] do_writepages+0x23/0x40
 [<ffffffff811cc3ee>] __writeback_single_inode+0x4e/0x250
 [<ffffffff811cd4f1>] writeback_sb_inodes+0x2c1/0x470
 [<ffffffff811cd73e>] __writeback_inodes_wb+0x9e/0xd0
 [<ffffffff811cda0b>] wb_writeback+0x1fb/0x2d0
 [<ffffffff811cdb7c>] wb_do_writeback+0x9c/0x220
 [<ffffffff811ce232>] bdi_writeback_workfn+0x72/0x1c0
 [<ffffffff8106b74e>] process_one_work+0x1de/0x5b0
 [<ffffffff8106e78f>] worker_thread+0x11f/0x3e0
 [<ffffffff810750ce>] kthread+0xde/0xf0
 [<ffffffff817093f8>] ret_from_fork+0x58/0x90

fsstress thread stack:
 [<ffffffff81139f0e>] sleep_on_page+0xe/0x20
 [<ffffffff81139ef7>] __lock_page+0x67/0x70
 [<ffffffff8113b100>] find_lock_page+0x50/0x80
 [<ffffffff8113b24f>] find_or_create_page+0x3f/0xb0
 [<ffffffffa06983a9>] sync_node_pages+0x259/0x810 [f2fs]
 [<ffffffffa068d874>] write_checkpoint+0x1a4/0xce0 [f2fs]
 [<ffffffffa0686b0c>] f2fs_sync_fs+0x7c/0xd0 [f2fs]
 [<ffffffffa067c813>] f2fs_sync_file+0x143/0x5f0 [f2fs]
 [<ffffffff811d301b>] vfs_fsync_range+0x2b/0x40
 [<ffffffff811d304c>] vfs_fsync+0x1c/0x20
 [<ffffffff811d3291>] do_fsync+0x41/0x70
 [<ffffffff811d32d3>] SyS_fdatasync+0x13/0x20
 [<ffffffff817094a2>] system_call_fastpath+0x16/0x1b
 [<ffffffffffffffff>] 0xffffffffffffffff

The reason of this issue is:
CPU0:					CPU1:
 - f2fs_write_data_pages
					 - f2fs_sync_fs
					  - write_checkpoint
					   - block_operations
					    - f2fs_lock_all
					     - down_write(sbi->cp_rwsem)
  - lock_page(page)
  - f2fs_write_data_page
					    - sync_node_pages
					     - flush_inline_data
					      - pagecache_get_page(page, GFP_LOCK)
   - f2fs_lock_op
    - down_read(sbi->cp_rwsem)

This patch alters to use trylock_page in flush_inline_data to fix this ABBA
deadlock issue.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-10-29 23:12:32 +08:00
Chao Yu
09f4658771 f2fs: introduce f2fs_flush_merged_bios for cleanup
Add a new helper f2fs_flush_merged_bios to clean up redundant codes.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-10-29 23:12:32 +08:00
Chao Yu
cc7e1e5fe8 f2fs: introduce f2fs_update_data_blkaddr for cleanup
Add a new help f2fs_update_data_blkaddr to clean up redundant codes.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-10-29 23:12:32 +08:00
Chao Yu
e90d738a5e f2fs crypto: fix incorrect positioning for GCing encrypted data page
For now, flow of GCing an encrypted data page:
1) try to grab meta page in meta inode's mapping with index of old block
address of that data page
2) load data of ciphertext into meta page
3) allocate new block address
4) write the meta page into new block address
5) update block address pointer in direct node page.

Other reader/writer will use f2fs_wait_on_encrypted_page_writeback to
check and wait on GCed encrypted data cached in meta page writebacked
in order to avoid inconsistence among data page cache, meta page cache
and data on-disk when updating.

However, we will use new block address updated in step 5) as an index to
lookup meta page in inner bio buffer. That would be wrong, and we will
never find the GCing meta page, since we use the old block address as
index of that page in step 1).

This patch fixes the issue by adjust the order of step 1) and step 3),
and in step 1) grab page with index generated in step 3).

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

 Conflicts:
	fs/f2fs/gc.c
2016-10-29 23:12:32 +08:00
Chao Yu
b22711753f f2fs: fix incorrect upper bound when iterating inode mapping tree
1. Inode mapping tree can index page in range of [0, ULONG_MAX], however,
in some places, f2fs only search or iterate page in ragne of [0, LONG_MAX],
result in miss hitting in page cache.

2. filemap_fdatawait_range accepts range parameters in unit of bytes, so
the max range it covers should be [0, LLONG_MAX], if we use [0, LONG_MAX]
as range for waiting on writeback, big number of pages will not be covered.

This patch corrects above two issues.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-10-29 23:12:32 +08:00
Yunlei He
76fa243e45 f2fs: avoid hungtask problem caused by losing wake_up
The D state of wait_on_all_pages_writeback should be waken by
function f2fs_write_end_io when all writeback pages have been
succesfully written to device. It's possible that wake_up comes
between get_pages and io_schedule. Maybe in this case it will
lost wake_up and still in D state even if all pages have been
write back to device, and finally, the whole system will be into
the hungtask state.

                if (!get_pages(sbi, F2FS_WRITEBACK))
                         break;
					<---------  wake_up
                io_schedule();

Signed-off-by: Yunlei He <heyunlei@huawei.com>
Signed-off-by: Biao He <hebiao6@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-10-29 23:12:32 +08:00
Chao Yu
d37aaf04b7 f2fs: trace old block address for CoWed page
This patch enables to trace old block address of CoWed page for better
debugging.

f2fs_submit_page_mbio: dev = (1,0), ino = 1, page_index = 0x1d4f0, oldaddr = 0xfe8ab, newaddr = 0xfee90 rw = WRITE_SYNC, type = NODE
f2fs_submit_page_mbio: dev = (1,0), ino = 1, page_index = 0x1d4f8, oldaddr = 0xfe8b0, newaddr = 0xfee91 rw = WRITE_SYNC, type = NODE
f2fs_submit_page_mbio: dev = (1,0), ino = 1, page_index = 0x1d4fa, oldaddr = 0xfe8ae, newaddr = 0xfee92 rw = WRITE_SYNC, type = NODE

f2fs_submit_page_mbio: dev = (1,0), ino = 134824, page_index = 0x96, oldaddr = 0xf049b, newaddr = 0x2bbe rw = WRITE, type = DATA
f2fs_submit_page_mbio: dev = (1,0), ino = 134824, page_index = 0x97, oldaddr = 0xf049c, newaddr = 0x2bbf rw = WRITE, type = DATA
f2fs_submit_page_mbio: dev = (1,0), ino = 134824, page_index = 0x98, oldaddr = 0xf049d, newaddr = 0x2bc0 rw = WRITE, type = DATA

f2fs_submit_page_mbio: dev = (1,0), ino = 135260, page_index = 0x47, oldaddr = 0xffffffff, newaddr = 0xf2631 rw = WRITE, type = DATA
f2fs_submit_page_mbio: dev = (1,0), ino = 135260, page_index = 0x48, oldaddr = 0xffffffff, newaddr = 0xf2632 rw = WRITE, type = DATA
f2fs_submit_page_mbio: dev = (1,0), ino = 135260, page_index = 0x49, oldaddr = 0xffffffff, newaddr = 0xf2633 rw = WRITE, type = DATA

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-10-29 23:12:32 +08:00
Chao Yu
3ccd1c10f5 f2fs: try to flush inode after merging inline data
When flushing node pages, if current node page is an inline inode page, we
will try to merge inline data from data page into inline inode page, then
skip flushing current node page, it will decrease the number of nodes to
be flushed in batch in this round, which may lead to worse performance.

This patch gives a chance to flush just merged inline inode pages for
performance.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-10-29 23:12:32 +08:00
Chao Yu
7ad7e4c310 f2fs: show more info about superblock recovery
This patch changes to show more info in message log about the recovery
of the corrupted superblock during ->mount, e.g. the index of corrupted
superblock and the result of recovery.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-10-29 23:12:32 +08:00
Chao Yu
5c16430b87 f2fs: fix the wrong stat count of calling gc
With a partition which was formated as multi segments in one section,
we stated incorrectly for count of gc operation.

e.g., for a partition with segs_per_sec = 4

cat /sys/kernel/debug/f2fs/status

GC calls: 208 (BG: 7)
  - data segments : 104 (52)
  - node segments : 104 (24)

GC called count should be (104 (data segs) + 104 (node segs)) / 4 = 52,
rather than 208. Fix it.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-10-29 23:12:32 +08:00
Jaegeuk Kim
60f5accac7 f2fs: remain last victim segment number ascending order
This patch avoids to remain inefficient victim segment number selected by
a victim.

For example, if all the dirty segments has same valid blocks, we can get
the victim segments descending order due to keeping wrong last segment number.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-10-29 23:12:32 +08:00
Shawn Lin
e8d08bb60c f2fs: reuse read_inline_data for f2fs_convert_inline_page
f2fs_convert_inline_page introduce what read_inline_data
already does for copying out the inline data from inode_page.
We can use read_inline_data instead to simplify the code.

Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-10-29 23:12:32 +08:00
Chao Yu
dd44751411 f2fs: fix to delete old dirent in converted inline directory in ->rename
When doing test with fstests/generic/068 in inline_dentry enabled f2fs,
following oops dmesg will be reported:

 ------------[ cut here ]------------
 WARNING: CPU: 5 PID: 11841 at fs/inode.c:273 drop_nlink+0x49/0x50()
 Modules linked in: f2fs(O) ip6table_filter ip6_tables ebtable_nat ebtables nf_conntrack_ipv4 nf_defrag_ipv4 xt_state
 CPU: 5 PID: 11841 Comm: fsstress Tainted: G           O    4.5.0-rc1 #45
 Hardware name: Hewlett-Packard HP Z220 CMT Workstation/1790, BIOS K51 v01.61 05/16/2013
  0000000000000111 ffff88009cdf7ae8 ffffffff813e5944 0000000000002e41
  0000000000000000 0000000000000111 0000000000000000 ffff88009cdf7b28
  ffffffff8106a587 ffff88009cdf7b58 ffff8804078fe180 ffff880374a64e00
 Call Trace:
  [<ffffffff813e5944>] dump_stack+0x48/0x64
  [<ffffffff8106a587>] warn_slowpath_common+0x97/0xe0
  [<ffffffff8106a5ea>] warn_slowpath_null+0x1a/0x20
  [<ffffffff81231039>] drop_nlink+0x49/0x50
  [<ffffffffa07b95b4>] f2fs_rename2+0xe04/0x10c0 [f2fs]
  [<ffffffff81231ff1>] ? lock_two_nondirectories+0x81/0x90
  [<ffffffff813f454d>] ? lockref_get+0x1d/0x30
  [<ffffffff81220f70>] vfs_rename+0x2e0/0x640
  [<ffffffff8121f9db>] ? lookup_dcache+0x3b/0xd0
  [<ffffffff810b8e41>] ? update_fast_ctr+0x21/0x40
  [<ffffffff8134ff12>] ? security_path_rename+0xa2/0xd0
  [<ffffffff81224af6>] SYSC_renameat2+0x4b6/0x540
  [<ffffffff810ba8ed>] ? trace_hardirqs_off+0xd/0x10
  [<ffffffff810022ba>] ? exit_to_usermode_loop+0x7a/0xd0
  [<ffffffff817e0ade>] ? int_ret_from_sys_call+0x52/0x9f
  [<ffffffff810bdc90>] ? trace_hardirqs_on_caller+0x100/0x1c0
  [<ffffffff81224b8e>] SyS_renameat2+0xe/0x10
  [<ffffffff8121f08e>] SyS_rename+0x1e/0x20
  [<ffffffff817e0957>] entry_SYSCALL_64_fastpath+0x12/0x6f
 ---[ end trace 2b31e17995404e42 ]---

This is because: in the same inline directory, when we renaming one file
from source name to target name which is not existed, once space of inline
dentry is not enough, inline conversion will be triggered, after that all
data in inline dentry will be moved to normal dentry page.

After attaching the new entry in coverted dentry page, still we try to
remove old entry in original inline dentry, since old entry has been
moved, so it obviously doesn't make any effect, result in remaining old
entry in converted dentry page.

Now, we have two valid dentries pointed to the same inode which has nlink
value of 1, deleting them both, above warning appears.

This issue can be reproduced easily as below steps:
1. mount f2fs with inline_dentry option
2. mkdir dir
3. touch 180 files named [001-180] in dir
4. rename dir/180 dir/181
5. rm dir/180 dir/181

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-10-29 23:12:31 +08:00
Chao Yu
7af1656411 f2fs: detect error of update_dent_inode in ->rename
Should check and show correct return value of update_dent_inode in
->rename.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-10-29 23:12:31 +08:00
Shawn Lin
a03b195403 f2fs: move sanity checking of cp into get_valid_checkpoint
>From the function name of get_valid_checkpoint, it seems to return
the valid cp or NULL for caller to check. If no valid one is found,
f2fs_fill_super will print the err log. But if get_valid_checkpoint
get one valid(the return value indicate that it's valid, however actually
it is invalid after sanity checking), then print another similar err
log. That seems strange. Let's keep sanity checking inside the procedure
of geting valid cp. Another improvement we gained from this move is
that even the large volume is supported, we check the cp in advanced
to skip the following procedure if failing the sanity checking.

Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-10-29 23:12:31 +08:00
Shawn Lin
1d4eb788ac f2fs: slightly reorganize read_raw_super_block
read_raw_super_block was introduced to help find the
first valid superblock. Commit da554e48caab ("f2fs:
recovering broken superblock during mount") changed the
behaviour to read both of them and check whether need
the recovery flag or not. So the comment before this
function isn't consistent with what it actually does.
Also, the origin code use two tags to round the err
cases, which isn't so readable. So this patch amend
the comment and slightly reorganize it.

Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-10-29 23:12:31 +08:00
Chao Yu
33336cb167 f2fs: reorder nat cache lock in cache_nat_entry
When lookuping nat entry in cache_nat_entry, if we fail to hit nat cache,
we try to load nat entries a) from journal of current segment cache or b)
from NAT pages for updating, during the process, write lock of
nat_tree_lock will be held to avoid inconsistent condition in between
nid cache and nat cache caused by racing among nat entry shrinker,
checkpointer, nat entry updater.

But this way may cause low efficient when updating nat cache, because it
serializes accessing in journal cache or reading NAT pages.

Here, we reorder lock and update flow as below to enhance accessing
concurrency:

 - get_node_info
  - down_read(nat_tree_lock)
  - lookup nat cache --- hit -> unlock & return
  - lookup journal cache --- hit -> unlock & goto update
  - up_read(nat_tree_lock)
update:
  - down_write(nat_tree_lock)
  - cache_nat_entry
   - lookup nat cache --- nohit -> update
  - up_write(nat_tree_lock)

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-10-29 23:12:31 +08:00
Chao Yu
626dcbd8f5 f2fs: split journal cache from curseg cache
In curseg cache, f2fs caches two different parts:
 - datas of current summay block, i.e. summary entries, footer info.
 - journal info, i.e. sparse nat/sit entries or io stat info.

With this approach, 1) it may cause higher lock contention when we access
or update both of the parts of cache since we use the same mutex lock
curseg_mutex to protect the cache. 2) current summary block with last
journal info will be writebacked into device as a normal summary block
when flushing, however, we treat journal info as valid one only in current
summary, so most normal summary blocks contain junk journal data, it wastes
remaining space of summary block.

So, in order to fix above issues, we split curseg cache into two parts:
a) current summary block, protected by original mutex lock curseg_mutex
b) journal cache, protected by newly introduced r/w semaphore journal_rwsem

When loading curseg cache during ->mount, we store summary info and
journal info into different caches; When doing checkpoint, we combine
datas of two cache into current summary block for persisting.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-10-29 23:12:31 +08:00
Chao Yu
80f42a5919 f2fs: enhance IO path with block plug
Try to use block plug in more place as below to let process cache bios
as much as possbile, in order to reduce lock overhead of queue in IO
scheduler.
1) sync_meta_pages
2) ra_meta_pages
3) f2fs_balance_fs_bg

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-10-29 23:12:31 +08:00
Chao Yu
0f9485738f f2fs: introduce f2fs_journal struct to wrap journal info
Introduce a new structure f2fs_journal to wrap journal info in struct
f2fs_summary_block for readability.

struct f2fs_journal {
	union {
		__le16 n_nats;
		__le16 n_sits;
	};
	union {
		struct nat_journal nat_j;
		struct sit_journal sit_j;
		struct f2fs_extra_info info;
	};
} __packed;

struct f2fs_summary_block {
	struct f2fs_summary entries[ENTRIES_IN_SUM];
	struct f2fs_journal journal;
	struct summary_footer footer;
} __packed;

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-10-29 23:12:31 +08:00
Chao Yu
06f3d93e20 f2fs crypto: avoid unneeded memory allocation when {en/de}crypting symlink
This patch adopts f2fs with codes of ext4, it removes unneeded memory
allocation in creating/accessing path of symlink.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

 Conflicts:
	fs/f2fs/crypto_fname.c
2016-10-29 23:12:31 +08:00
Chao Yu
3b92fcd38b f2fs crypto: handle unexpected lack of encryption keys
This patch syncs f2fs with commit abdd438b26b4 ("ext4 crypto: handle
unexpected lack of encryption keys") from ext4.

Fix up attempts by users to try to write to a file when they don't
have access to the encryption key.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-10-29 23:12:31 +08:00
Chao Yu
a18a1be377 f2fs crypto: make sure the encryption info is initialized on opendir(2)
This patch syncs f2fs with commit 6bc445e0ff44 ("ext4 crypto: make
sure the encryption info is initialized on opendir(2)") from ext4.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-10-29 23:12:31 +08:00
Chao Yu
3d95525a4a f2fs: support revoking atomic written pages
f2fs support atomic write with following semantics:
1. open db file
2. ioctl start atomic write
3. (write db file) * n
4. ioctl commit atomic write
5. close db file

With this flow we can avoid file becoming corrupted when abnormal power
cut, because we hold data of transaction in referenced pages linked in
inmem_pages list of inode, but without setting them dirty, so these data
won't be persisted unless we commit them in step 4.

But we should still hold journal db file in memory by using volatile
write, because our semantics of 'atomic write support' is incomplete, in
step 4, we could fail to submit all dirty data of transaction, once
partial dirty data was committed in storage, then after a checkpoint &
abnormal power-cut, db file will be corrupted forever.

So this patch tries to improve atomic write flow by adding a revoking flow,
once inner error occurs in committing, this gives another chance to try to
revoke these partial submitted data of current transaction, it makes
committing operation more like aotmical one.

If we're not lucky, once revoking operation was failed, EAGAIN will be
reported to user for suggesting doing the recovery with held journal file,
or retrying current transaction again.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-10-29 23:12:31 +08:00
Chao Yu
6399d80f86 f2fs: split drop_inmem_pages from commit_inmem_pages
Split drop_inmem_pages from commit_inmem_pages for code readability,
and prepare for the following modification.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-10-29 23:12:31 +08:00
Jaegeuk Kim
de89056ac2 f2fs: avoid garbage lenghs in dentries
This patch fixes to eliminate garbage name lengths in dentries in order
to provide correct answers of readdir.

For example, if a valid dentry consists of:
 bitmap : 1   1 1 1
 len    : 32  0 x 0,

readdir can start with second bit_pos having len = 0.
Or, it can start with third bit_pos having garbage.

In both of cases, we should avoid to try filling dentries.
So, this patch not only removes any garbage length, but also avoid entering
zero length case in readdir.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-10-29 23:12:30 +08:00
Jaegeuk Kim
9be179b0be f2fs: use correct errno
This patch is to fix misused error number.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-10-29 23:12:30 +08:00
Jaegeuk Kim
f87ff6041f f2fs crypto: add missing locking for keyring_key access
This patch adopts:
	ext4 crypto: add missing locking for keyring_key access

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

 Conflicts:
	fs/f2fs/crypto_key.c
2016-10-29 23:12:30 +08:00