sync can currently take a really long time if a concurrent writer is
extending a file. The problem is that the dirty pages on the address
space grow in the same direction as write_cache_pages scans, so if
the writer keeps ahead of writeback, the writeback will not
terminate until the writer stops adding dirty pages.

For a data integrity sync, we only need to write the pages dirty at
the time we start the writeback, so we can stop scanning once we get
to the page that was at the end of the file at the time the scan
started.

This will prevent operations like copying a large file preventing
sync from completing as it will not write back pages that were
dirtied after the sync was started. This does not impact the
existing integrity guarantees, as any dirty page (old or new)
within the EOF range at the start of the scan will still be
captured.

This patch will not prevent sync from blocking on large writes into
holes. That requires more complex intervention while this patch only
addresses the common append-case of this sync holdoff.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Now that the background flush code has been fixed, we shouldn't need to
silently multiply the wbc->nr_to_write to get good writeback. Remove
that code.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

If a filesystem writes more than one page in ->writepage, write_cache_pages
fails to notice this and continues to attempt writeback when wbc->nr_to_write
has gone negative - this trace was captured from XFS:

    wbc_writeback_start: towrt=1024
    wbc_writepage: towrt=1024
    wbc_writepage: towrt=0
    wbc_writepage: towrt=-1
    wbc_writepage: towrt=-5
    wbc_writepage: towrt=-21
    wbc_writepage: towrt=-85

This has adverse effects on filesystem writeback behaviour. write_cache_pages()
needs to terminate after a certain number of pages are written, not after a
certain number of calls to ->writepage are made.  This is a regression
introduced by 17bc6c30 ("vfs: Add
no_nrwrite_index_update writeback control flag"), but cannot be reverted
directly due to subsequent bug fixes that have gone in on top of it.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

* 'bkl/fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing:
  hp_sdc_rtc: fix broken ioctl conversion

Commit 55929332 "drivers: Push down BKL into various drivers"
introduced a regression in hp_sdc_rtc, caused by a missing
change of the .unlocked_ioctl pointer to the newly introduced
function.

Fixes:

	drivers/input/misc/hp_sdc_rtc.c:681: warning: initialization from
	incompatible pointer type
	drivers/input/misc/hp_sdc_rtc.c:665: warning:
	‘hp_sdc_rtc_unlocked_ioctl’ defined but not used
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>

* git://git.infradead.org/~dwmw2/mtd-2.6.35:
  jffs2: update ctime when changing the file's permission by setfacl
  jffs2: Fix NFS race by using insert_inode_locked()
  jffs2: Fix in-core inode leaks on error paths
  mtd: Fix NAND submenu
  mtd/r852: update card detect early.
  mtd/r852: Fixes in case of DMA timeout
  mtd/r852: register IRQ as last step
  drivers/mtd: Use memdup_user
  docbook: make mtd nand module init static

* 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jgarzik/libata-dev:
  ahci: redo stopping DMA engines on empty ports
  sata_sil24: fix kernel panic on ARM caused by unaligned access in sata_sil24
  ahci: add pci quirk for JMB362
  sata_via: explain the magic fix

Commit 96d60303 (ahci: Turn off DMA engines when there's no device)
implemented stopping DMA engines on empty ports but it used single
sampling of status registers to determine device presence which led to
disabling of DMA engines on occupied ports.  Do it after all EH
actions are complete using device presence state determined by EH.
This avoids spurious disabling of DMA engines and simplifies the code.
Signed-off-by: Tejun Heo <tj@kernel.org>
Tested-by: Marc Dionne <marc.c.dionne@gmail.com>
Cc: Matthew Garrett <mjg@redhat.com>
Cc: Robert Hancock <hancockrwd@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

The sata_sil24 driver has six 16-bit registers that are initialised with
32-bit writes. This cause a kernel panic on ARM due to the unaligned
accesses which result.

This patch changes the accesses to the correct 16-bit ones.
Signed-off-by: Colin Tuckley <colin.tuckley@arm.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

JMB362 is a new variant of jmicron controller which is similar to
JMB360 but has two SATA ports instead of one.  As there is no PATA
port, single function AHCI mode can be used as in JMB360.  Add pci
quirk for JMB362.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Aries Lee <arieslee@jmicron.com>
Cc: stable@kernel.org
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

Add Joseph Chan's explanation of the problem and workaround to the
VT6421 magic fix.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Joseph Chan <JosephChan@via.com.tw>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

At the point of the call to dev_err, wm8350 is NULL.

A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)

// <smpl>
@r exists@
expression E,E1;
identifier f;
statement S1,S2,S3;
@@

if ((E == NULL && ...) || ...)
{
  ... when != if (...) S1 else S2
      when != E = E1
* E->f
  ... when any
  return ...;
}
else S3
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>

This reverts commit 962400e8, which was
entirely bogus.

The code used to multiply the character offset by "vc->vc_cols", and
that's actually correct, because 'd' itself is an 'unsigned short'.  So
the pointer arithmetic already takes the size of a VGA character into
account.  Changing it to use vc_size_row (which is just "vc_cols"
shifted up to take the size of the character into account) ends up
multiplying with the VGA character size twice.

This got reported as bugs for various other subsystems, because what it
actually results in is writing the 16-bit vc_video_erase_char pattern
(usually 0x0720: 0x07 is the default attribute, 0x20 is ASCII space)
into some random other allocation.

So Markus ended up reporting this as a ext4 bug, while to Torsten Kaiser
it looked like a problem with KMS or libata.  Jeff Chua saw it in
different places.

And finally - Justin Mattock had slab poisoning enabled, and saw it as a
slab poison overwritten.  And bisected and reverted this to verify the
buggy commit.
Reported-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Reported-by: Torsten Kaiser <just.for.lkml@googlemail.com>
Reported-by: Jeff Chua <jeff.chua.linux@gmail.com>
Reported-by: Justin P. Mattock <justinmattock@gmail.com>
Reported-bisected-and-tested-by: Justin P. Mattock <justinmattock@gmail.com>
Acked-by: Dave Airlie <airlied@redhat.com>
Cc: Frank Pan <frankpzh@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

jffs2 didn't update the ctime of the file when its permission was changed.

Steps to reproduce:
 # touch aaa
 # stat -c %Z aaa
 1275289822
 # setfacl -m  'u::x,g::x,o::x' aaa
 # stat -c %Z aaa
 1275289822                         <- unchanged

But, according to the spec of the ctime, jffs2 must update it.

Port of ext3 patch by Miao Xie <miaox@cn.fujitsu.com>.
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

Cursors need to be in the GTT domain when being accessed by the GPU.
Previously this was a fortuitous byproduct of userspace using pwrite()
to upload the image data into the cursor. The redundant clflush was
removed in commit 9b8c4a and so the image was no longer being flushed
out of the caches into main memory. One could also devise a scenario
where the cursor was rendered by the GPU, prior to being attached as the
cursor, resulting in similar corruption due to the missing MI_FLUSH.

Fixes:

  Bug 28335 - Cursor corruption caused by commit 9b8c4a0b
  https://bugs.freedesktop.org/show_bug.cgi?id=28335Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reported-and-tested-by: Jeff Chua <jeff.chua.linux@gmail.com>
Tested-by: Linus Torvalds <torvalds@linux-foundation.org>
Reported-by: Andy Isaacson <adi@hexapodia.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: Fix remaining racy updates of EXT4_I(inode)->i_flags
  ext4: Make sure the MOVE_EXT ioctl can't overwrite append-only files

A few functions were still modifying i_flags in a racy manner.
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

* 'for-linus' of git://oss.sgi.com/xfs/xfs:
  xfs: improve xfs_isilocked
  xfs: skip writeback from reclaim context
  xfs: remove done roadmap item from xfs-delayed-logging-design.txt
  xfs: fix race in inode cluster freeing failing to stale inodes
  xfs: fix access to upper inodes without inode64
  xfs: fix might_sleep() warning when initialising per-ag tree
  fs/xfs/quota: Add missing mutex_unlock
  xfs: remove duplicated #include
  xfs: convert more trace events to DEFINE_EVENT
  xfs: xfs_trace.c: remove duplicated #include
  xfs: Check new inode size is OK before preallocating
  xfs: clean up xlog_align
  xfs: cleanup log reservation calculactions
  xfs: be more explicit if RT mount fails due to config
  xfs: replace E2BIG with EFBIG where appropriate

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (30 commits)
  X25: remove duplicated #include
  tcp: use correct net ns in cookie_v4_check()
  rps: tcp: fix rps_sock_flow_table table updates
  ppp_generic: fix multilink fragment sizes
  syncookies: remove Kconfig text line about disabled-by-default
  ixgbe: only check pfc bits in hang logic if pfc is enabled
  net: check for refcount if pop a stacked dst_entry
  ixgbe: return IXGBE_ERR_RAR_INDEX when out of range
  act_pedit: access skb->data safely
  sfc: Store port number in net_device::dev_id
  epic100: Test __BIG_ENDIAN instead of (non-existent) CONFIG_BIG_ENDIAN
  tehuti: return -EFAULT on copy_to_user errors
  isdn/kcapi: return -EFAULT on copy_from_user errors
  e1000e: change logical negate to bitwise
  sfc: Get port number from CS_PORT_NUM, not PCI function number
  cls_u32: use skb_header_pointer() to dereference data safely
  TCP: tcp_hybla: Fix integer overflow in slow start increment
  act_nat: fix the wrong checksum when addr isn't in old_addr/mask
  net/fec: fix pm to survive to suspend/resume
  korina: count RX DMA OVR as rx_fifo_error
  ...

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ryusuke/nilfs2:
  nilfs2: remove obsolete declarations of cache constructor and destructor
  nilfs2: fix style issue in nilfs_destroy_cachep

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6:
  Minix: Clean up left over label
  fix truncate inode time modification breakage
  fix setattr error handling in sysfs, configfs
  fcntl: return -EFAULT if copy_to_user fails
  wrong type for 'magic' argument in simple_fill_super()
  fix the deadlock in qib_fs
  mqueue doesn't need make_bad_inode()

* git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus:
  module: fix bne2 "gave up waiting for init of module libcrc32c"
  module: verify_export_symbols under the lock
  module: move find_module check to end
  module: make locking more fine-grained.
  module: Make module sysfs functions private.
  module: move sysfs exposure to end of load_module
  module: fix kdb's illicit use of struct module_use.
  module: Make the 'usage' lists be two-way

Problem: it's hard to avoid an init routine stumbling over a
request_module these days.  And it's not clear it's always a bad idea:
for example, a module like kvm with dynamic dependencies on kvm-intel
or kvm-amd would be neater if it could simply request_module the right
one.

In this particular case, it's libcrc32c:

	libcrc32c_mod_init
	 crypto_alloc_shash
	  crypto_alloc_tfm
	   crypto_find_alg
	    crypto_alg_mod_lookup
	     crypto_larval_lookup
	      request_module

If another module is waiting inside resolve_symbol() for libcrc32c to
finish initializing (ie. bne2 depends on libcrc32c) then it does so
holding the module lock, and our request_module() can't make progress
until that is released.

Waiting inside resolve_symbol() without the lock isn't all that hard:
we just need to pass the -EBUSY up the call chain so we can sleep
where we don't hold the lock.  Error reporting is a bit trickier: we
need to copy the name of the unfinished module before releasing the
lock.

Other notes:
1) This also fixes a theoretical issue where a weak dependency would allow
   symbol version mismatches to be ignored.
2) We rename use_module to ref_module to make life easier for the only
   external user (the out-of-tree ksplice patches).
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Tim Abbot <tabbott@ksplice.com>
Tested-by: Brandon Philips <bphilips@suse.de>

It disabled preempt so it was "safe", but nothing stops another module
slipping in before this module is added to the global list now we don't
hold the lock the whole time.

So we check this just after we check for duplicate modules, and just
before we put the module in the global list.

(find_symbol finds symbols in coming and going modules, too).
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

I think Rusty may have made the lock a bit _too_ finegrained there, and
didn't add it to some places that needed it. It looks, for example, like
PATCH 1/2 actually drops the lock in places where it's needed
("find_module()" is documented to need it, but now load_module() didn't
hold it at all when it did the find_module()).

Rather than adding a new "module_loading" list, I think we should be able
to just use the existing "modules" list, and just fix up the locking a
bit.

In fact, maybe we could just move the "look up existing module" a bit
later - optimistically assuming that the module doesn't exist, and then
just undoing the work if it turns out that we were wrong, just before
adding ourselves to the list.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

Kay Sievers <kay.sievers@vrfy.org> reports that we still have some
contention over module loading which is slowing boot.

Linus also disliked a previous "drop lock and regrab" patch to fix the
bne2 "gave up waiting for init of module libcrc32c" message.

This is more ambitious: we only grab the lock where we need it.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Brandon Philips <brandon@ifup.org>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>

These were placed in the header in ef665c1a to get the various
SYSFS/MODULE config combintations to compile.

That may have been necessary then, but it's not now.  These functions
are all local to module.c.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Randy Dunlap <randy.dunlap@oracle.com>

This means a little extra work, but is more logical: we don't put
anything in sysfs until we're about to put the module into the
global list an parse its parameters.

This also gives us a logical place to put duplicate module detection
in the next patch.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

Linus changed the structure, and luckily this didn't compile any more.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Martin Hicks <mort@sgi.com>

When adding a module that depends on another one, we used to create a
one-way list of "modules_which_use_me", so that module unloading could
see who needs a module.

It's actually quite simple to make that list go both ways: so that we
not only can see "who uses me", but also see a list of modules that are
"used by me".

In fact, we always wanted that list in "module_unload_free()": when we
unload a module, we want to also release all the other modules that are
used by that module.  But because we didn't have that list, we used to
first iterate over all modules, and then iterate over each "used by me"
list of that module.

By making the list two-way, we simplify module_unload_free(), and it
allows for some trivial fixes later too.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (cleaned & rebased)

Remove duplicated #include('s) in drivers/net/wan/x25_asy.c
Signed-off-by: Huang Weiyi <weiyi.huang@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Its better to make a route lookup in appropriate namespace.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

I believe a moderate SYN flood attack can corrupt RFS flow table
(rps_sock_flow_table), making RPS/RFS much less effective.

Even in a normal situation, server handling short lived sessions suffer
from bad steering for the first data packet of a session, if another SYN
packet is received for another session.

We do following action in tcp_v4_rcv() :

	sock_rps_save_rxhash(sk, skb->rxhash);

We should _not_ do this if sk is a LISTEN socket, as about each
packet received on a LISTEN socket has a different rxhash than
previous one.
 -> RPS_NO_CPU markers are spread all over rps_sock_flow_table.

Also, it makes sense to protect sk->rxhash field changes with socket
lock (We currently can change it even if user thread owns the lock
and might use rxhash)

This patch moves sock_rps_save_rxhash() to a sock locked section,
and only for non LISTEN sockets.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Fix bug in multilink fragment size calculation introduced by
commit 9c705260
"ppp: ppp_mp_explode() redesign"
Signed-off-by: Ben McKeegan <ben@netservers.co.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

syncookies default to on since
e994b7c9
(tcp: Don't make syn cookies initial setting depend on CONFIG_SYSCTL).
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

Only check pfc bits in hang logic if PFC is enabled.  Previously,
if DCB was enabled but PFC was disabled the incorrect pause
bits would be checked.
Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Acked-by: Don Skidmore <donald.c.skidmore@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

xfrm triggers a warning if dst_pop() drops a refcount
on a noref dst. This patch changes dst_pop() to
skb_dst_pop(). skb_dst_pop() drops the refcnt only
on a refcounted dst. Also we don't clone the child
dst_entry, so it is not refcounted and we can use
skb_dst_set_noref() in xfrm_output_one().
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
  Input: wacom - add Cintiq 21UX2 and Intuos4 WL
  Input: ads7846 - fix compiler warning in ads7846_probe()
  Input: tps6507x-ts - a couple work queue cleanups
  Input: s3c2410_ts - tone down logging
  Input: s3c2410_ts - fix build error due to ADC Kconfig rename

* git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6: (23 commits)
  sh: Make intc messages consistent via pr_fmt.
  sh: make sure static declaration on ms7724se
  sh: make sure static declaration on mach-migor
  sh: make sure static declaration on mach-ecovec24
  sh: make sure static declaration on mach-ap325rxa
  clocksource: sh_cmt: compute mult and shift before registration
  clocksource: sh_tmu: compute mult and shift before registration
  sh: PIO disabling for x3proto and urquell.
  sh: mach-sdk7786: conditionally disable PIO support.
  sh: support for platforms without PIO.
  usb: r8a66597-hcd pio to mmio accessor conversion.
  usb: gadget: r8a66597-udc pio to mmio accessor conversion.
  usb: gadget: m66592-udc pio to mmio accessor conversion.
  sh: add romImage MMCIF boot for sh7724 and Ecovec V2
  sh: add boot code to MMCIF driver header
  sh: prepare MMCIF driver header file
  sh: allow romImage data between head.S and the zero page
  sh: Add support MMCIF for ecovec
  sh: remove duplicated #include
  input: serio: disable i8042 for non-cayman sh platforms.
  ...