Commit 5e081591 "block: warn if tag is greater than real_max_depth"
cleaned up blk_queue_end_tag() to warn when the tag is truly invalid
(greater than real_max_depth).  However, it changed behavior in the tag <
max_depth case to not end the request.  Leading to triggering of
BUG_ON(blk_queued_rq(rq)) in the request completion path:

  http://marc.info/?l=linux-kernel&m=132204370518629&w=2

In order to allow blk_queue_resize_tags() to shrink the tag space
blk_queue_end_tag() must always complete tags with a value less than
real_max_depth regardless of the current max_depth.  The comment about
"handling the shrink case" seems to be what prompted changes in this
space, so remove it and BUG on all invalid tags (made even simpler by
Matthew's suggestion to use an unsigned compare).
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Cc: Tao Ma <boyu.mt@taobao.com>
Cc: Matthew Wilcox <matthew@wil.cx>
Reported-by: Meelis Roos <mroos@ut.ee>
Reported-by: Ed Nadolski <edmund.nadolski@intel.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Signed-off-by: majianpeng <majianpeng@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

All requests of a queue could be merged to other requests of other queue.
Such queue will not have request in it, but it's in service tree. This
will cause kernel oops.
I encounter a BUG_ON() in cfq_dispatch_request() with next patch, but the
issue should exist without the patch.
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

While probing, fd sets up queue, probes hardware and tears down the
queue if probing fails.  In the process, blk_drain_queue() kicks the
queue which failed to finish initialization and fd is unhappy about
that.

  floppy0: no floppy controllers found
  ------------[ cut here ]------------
  WARNING: at drivers/block/floppy.c:2929 do_fd_request+0xbf/0xd0()
  Hardware name: To Be Filled By O.E.M.
  VFS: do_fd_request called on non-open device
  Modules linked in:
  Pid: 1, comm: swapper Not tainted 3.2.0-rc4-00077-g5983fe2b #2
  Call Trace:
   [<ffffffff81039a6a>] warn_slowpath_common+0x7a/0xb0
   [<ffffffff81039b41>] warn_slowpath_fmt+0x41/0x50
   [<ffffffff813d657f>] do_fd_request+0xbf/0xd0
   [<ffffffff81322b95>] blk_drain_queue+0x65/0x80
   [<ffffffff81322c93>] blk_cleanup_queue+0xe3/0x1a0
   [<ffffffff818a809d>] floppy_init+0xdeb/0xe28
   [<ffffffff818a72b2>] ? daring+0x6b/0x6b
   [<ffffffff810002af>] do_one_initcall+0x3f/0x170
   [<ffffffff81884b34>] kernel_init+0x9d/0x11e
   [<ffffffff810317c2>] ? schedule_tail+0x22/0xa0
   [<ffffffff815dbb14>] kernel_thread_helper+0x4/0x10
   [<ffffffff81884a97>] ? start_kernel+0x2be/0x2be
   [<ffffffff815dbb10>] ? gs_change+0xb/0xb

Avoid it by making blk_drain_queue() kick queue iff dispatch queue has
something on it.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Ralf Hildebrandt <Ralf.Hildebrandt@charite.de>
Reported-by: Wu Fengguang <fengguang.wu@intel.com>
Tested-by: Sergei Trofimovich <slyich@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

The old PowerMac swim3 driver has some "interesting" locking issues,
using a private lock and failing to lock the queue before completing
requests, which triggered WARN_ONs among others.

This rips out the private lock, makes everything operate under the
block queue lock, and generally makes things simpler.

We used to also share a queue between the two possible instances which
was problematic since we might pick the wrong controller in some cases,
so make the queue and the current request per-instance and use
queuedata to point to our private data which is a lot cleaner.

We still share the queue lock but then, it's nearly impossible to actually
use 2 swim3's simultaneously: one would need to have a Wallstreet
PowerBook, the only machine afaik with two of these on the motherboard,
and populate both hotswap bays with a floppy drive (the machine ships
only with one), so nobody cares...

While at it, add a little fix to clear up stale interrupts when loading
the driver or plugging a floppy drive in a bay.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

discard_alignment is not relevant to the loop driver since it is
supposed to be set as a workaround for the old sector 63 alignments.
So set it to zero rather than block size.
Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Reported-by: Milan Broz <mbroz@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

cfq_cic_link() has race condition. When some processes which shared ioc
issue I/O to same block device simultaneously, cfq_cic_link() returns -EEXIST
sometimes. The race condition might stop I/O by following steps:

step  1: Process A: Issue an I/O to /dev/sda
step  2: Process A: Get an ioc (iocA here) in get_io_context() which does not
		    linked with a cic for the device
step  3: Process A: Get a new cic for the device (cicA here) in
		    cfq_alloc_io_context()

step  4: Process B: Issue an I/O to /dev/sda
step  5: Process B: Get iocA in get_io_context() since process A and B share the
		    same ioc
step  6: Process B: Get a new cic for the device (cicB here) in
		    cfq_alloc_io_context() since iocA has not been linked with a
		    cic for the device yet

step  7: Process A: Link cicA to iocA in cfq_cic_link()
step  8: Process A: Dispatch I/O to driver and finish it

step  9: Process B: Try to link cicB to iocA in cfq_cic_link()
		    But it fails with showing "cfq: cic link failed!" kernel
		    message, since iocA has already linked with cicA at step 7.
step 10: Process B: Wait for finishig I/O in get_request_wait()
		    The function does not wake up, when there is no I/O to the
		    device.

When cfq_cic_link() returns -EEXIST, it means ioc has already linked with cic.
So when cfq_cic_link() return -EEXIST, retry cfq_cic_lookup().
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: stable@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>

If we fail allocating the blkpg stats, we free cfqd and cfgq.
But we need to free the IDA cfqd->cic_index as well.
Signed-off-by: majianpeng <majianpeng@gmail.com>
Cc: stable@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>

We weren't filling in the transfer length of the
flush cache command (it transfers 4 bytes of zeroes).
Firmware didn't seem to be bothered by this, but it
should be fixed.
Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

IRQF_SHARED is required for older controllers that don't support MSI(X)
and which may end up sharing an interrupt.

Also remove deprecated IRQF_DISABLED.
Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

The loop driver does not support discard if encryption is enabled,
fix the comment.
Signed-off-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

struct request_queue is allocated with __GFP_ZERO so its "node" field is
zero before initialization.  This causes an oops if node 0 is offline in
the page allocator because its zonelists are not initialized.  From Dave
Young's dmesg:

	SRAT: Node 1 PXM 2 0-d0000000
	SRAT: Node 1 PXM 2 100000000-330000000
	SRAT: Node 0 PXM 1 330000000-630000000
	Initmem setup node 1 0000000000000000-000000000affb000
	...
	Built 1 zonelists in Node order, mobility grouping on.
	...
	BUG: unable to handle kernel paging request at 0000000000001c08
	IP: [<ffffffff8111c355>] __alloc_pages_nodemask+0xb5/0x870

and __alloc_pages_nodemask+0xb5 translates to a NULL pointer on
zonelist->_zonerefs.

The fix is to initialize q->node at the time of allocation so the correct
node is passed to the slab allocator later.

Since blk_init_allocated_queue_node() is no longer needed, merge it with
blk_init_allocated_queue().

[rientjes@google.com: changelog, initializing q->node]
Cc: stable@vger.kernel.org [2.6.37+]
Reported-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: David Rientjes <rientjes@google.com>
Tested-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

This reverts commit dc937280.

As requested by Ben Herrenschmidt:
  "This breaks some powerpc platforms at least.  The practice of having
   a node provide an explicit "interrupt-parent" property pointing to
   itself is an old trick that we've used in the past to allow a
   device-node to have interrupts routed to different controllers.

   In that case, the node also contains an interrupt-map, so the node is
   its own parent, the interrupt resolution hits the map, which then can
   route each individual interrupt to a different parent."

Grant says:
  "Ah, nuts, yes that is broken then.  Yes, please revert the commit and
   Rob & I will come up with a better solution.

   Rob, I think it can be done by explicitly checking for np ==
   desc->interrupt_parent in of_irq_init() instead of relying on
   of_irq_find_parent() returning NULL."
Requested-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: devicetree-discuss@lists.ozlabs.org
Cc: linuxppc-dev <linuxppc-dev@lists.ozlabs.org>
Cc: Tanmay Inamdar <tinamdar@apm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  mount_subtree() pointless use-after-free
  iio: fix a leak due to improper use of anon_inode_getfd()
  microblaze: bury asm/namei.h

d'oh... we'd carefully pinned mnt->mnt_sb down, dropped mnt and attempt
to grab s_umount on mnt->mnt_sb.  The trouble is, *mnt might've been
overwritten by now...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
  Input: ams_delta_serio - include linux/module.h
  Input: elantech - adjust hw_version detection logic
  Input: i8042 - add HP Pavilion dv4s to 'notimeout' and 'nomux' blacklists

* git://www.linux-watchdog.org/linux-watchdog:
  watchdog: fix initialisation printout in s3c2410_wdt
  watchdog: Don't overwrite error value in wm831x_wdt_set_timeout()
  watchdog: adx_wdt.c: remove driver

* 'bugfixes' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
  NFS: Revert pnfs ugliness from the generic NFS read code path
  SUNRPC: destroy freshly allocated transport in case of sockaddr init error
  NFS: Fix a regression in the referral code
  nfs: move nfs_file_operations declaration to bottom of file.c (try #2)
  nfs: when attempting to open a directory, fall back on normal lookup (try #5)

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: remove free-space-cache.c WARN during log replay
  Btrfs: sectorsize align offsets in fiemap
  Btrfs: clear pages dirty for io and set them extent mapped
  Btrfs: wait on caching if we're loading the free space cache
  Btrfs: prefix resize related printks with btrfs:
  btrfs: fix stat blocks accounting
  Btrfs: avoid unnecessary bitmap search for cluster setup
  Btrfs: fix to search one more bitmap for cluster setup
  btrfs: mirror_num should be int, not u64
  btrfs: Fix up 32/64-bit compatibility for new ioctls
  Btrfs: fix barrier flushes
  Btrfs: fix tree corruption after multi-thread snapshots and inode_cache flush

* 'writeback-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux:
  writeback: remove vm_dirties and task->dirties
  writeback: hard throttle 1000+ dd on a slow USB stick
  mm: Make task in balance_dirty_pages() killable

* 'staging-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
  staging: fix more ET131X build errors
  staging: et131x depends on NET
  staging: slicoss depends on NET
  linux-next: et131x: Fix build error when CONFIG_PM_SLEEP not enabled

* 'usb-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (48 commits)
  USB: Fix Corruption issue in USB ftdi driver ftdi_sio.c
  USB: option: add PID of Huawei E173s 3G modem
  OHCI: final fix for NVIDIA problems (I hope)
  USB: option: release new PID for ZTE 3G modem
  usb: Netlogic: Fix HC_LENGTH call in ehci-xls.c
  USB: storage: ene_ub6250: fix compile warnings
  USB: option: add id for 3G dongle Model VT1000 of Viettel
  USB: serial: pl2303: rm duplicate id
  USB: pch_udc: Change company name OKI SEMICONDUCTOR to LAPIS Semiconductor
  USB: pch_udc: Support new device LAPIS Semiconductor ML7831 IOH
  usb-storage: Accept 8020i-protocol commands longer than 12 bytes
  USB: quirks: adding more quirky webcams to avoid squeaky audio
  powerpc/usb: fix type cast for address of ioremap to compatible with 64-bit
  USB: at91: at91-ohci: fix set/get power
  USB: cdc-acm: Fix disconnect() vs close() race
  USB: add quirk for Logitech C600 web cam
  USB: EHCI: fix HUB TT scheduling issue with iso transfer
  USB: XHCI: resume root hubs when the controller resumes
  USB: workaround for bug in old version of GCC
  USB: ark3116 initialisation fix
  ...

* 'tty-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  TTY: ldisc, wait for ldisc infinitely in hangup
  TTY: ldisc, move wait idle to caller
  TTY: ldisc, allow waiting for ldisc arbitrarily long
  Revert "tty/serial: Prevent drop of DCD on suspend for Tegra UARTs"
  RS485: fix inconsistencies in the meaning of some variables
  pch_uart: Fix DMA resource leak issue
  serial,mfd: Fix CMSPAR setup
  tty/serial: Prevent drop of DCD on suspend for Tegra UARTs
  pch_uart: Change company name OKI SEMICONDUCTOR to LAPIS Semiconductor
  pch_uart: Support new device LAPIS Semiconductor ML7831 IOH
  pch_uart: Fix hw-flow control issue
  tty: hvc_dcc: Fix duplicate character inputs
  jsm: Change maintainership

Merge branch 'driver-core-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

* 'driver-core-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  drivers/base/node.c: fix compilation error with older versions of gcc
  uio: documentation fixups
  device.h: Fix struct member documentation

* 'char-misc-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
  misc: ad525x_dpot: Fix AD8400 spi transfer size.
  pch_phub: Fix MAC address writing issue for LAPIS ML7831
  pch_phub: Improve ADE(Address Decode Enable) control
  pch_phub: Change company name OKI SEMICONDUCTOR to LAPIS Semiconductor
  pch_phub: Support new device LAPIS Semiconductor ML7831 IOH
  pcie-gadget-spear: Add "platform:" prefix for platform modalias
  MAINTAINERS: add CHAR and MISC driver maintainers

it can fail and in that case ->release() will *not* be called...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

altroot support has been gone for years, along with arch/*/asm/namei.h;
looks like a dummy survivor that sat it out in microblaze tree...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

* 'dev' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: fix up a undefined error in ext4_free_blocks in debugging code
  ext4: add blk_finish_plug in error case of writepages.
  ext4: Remove kernel_lock annotations
  ext4: ignore journalled data options on remount if fs has no journal

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
  libceph: Allocate larger oid buffer in request msgs
  ceph: initialize root dentry
  ceph: fix iput race when queueing inode work

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  VFS: Log the fact that we've given ELOOP rather than creating a loop
  minixfs: kill manual hweight(), simplify
  fs/minix: Verify bitmap block counts before mounting

wrong register returned...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The log replay code only partially loads block groups, since
the block group caching code is able to detect and deal with
extents the logging code has pinned down.

While the logging code is pinning down block groups, there is
a bogus WARN_ON we're hitting if the code wasn't able to find
an extent in the cache.  This commit removes the warning because
it can happen any time there isn't a valid free space cache
for that block group.
Signed-off-by: Chris Mason <chris.mason@oracle.com>

sbi is not defined, so let ext4_free_blocks use EXT4_SB(sb) instead
when EXT4FS_DEBUG is defined.
Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com>

To prevent an NFS server from being used to create a directory loop in an NFS
superblock on the client, the following patch was committed:

	commit 18367501
	Author: Al Viro <viro@zeniv.linux.org.uk>
	Date:   Tue Jul 12 21:42:24 2011 -0400
	Subject: fix loop checks in d_materialise_unique()

This causes ELOOP to be reported to anyone trying to access the dentry that
would otherwise cause the kernel to complete the loop.

However, no indication is given to the caller as to why an operation that ought
to work doesn't.  The fault is with the kernel, which doesn't want to try and
solve the problem as it gets horrendously messy if there's another mountpoint
somewhere in the trees being spliced that can't be moved[*].

[*] The real problem is that we don't handle the excision of a subtree that
gets moved _out_ of what we can see.  This can happen on the server where a
directory is merely moved between two other dirs on the same filesystem, but
where destination dir is not accessible by the client.

So, given the choice to return ELOOP rather than trying to reconfigure the
dentry tree, we should give the caller some indication of why they aren't being
allowed to make what should be a legitimate request and log a message.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Sachin Prabhu <sprabhu@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (86 commits)
  ipv4: fix redirect handling
  ping: dont increment ICMP_MIB_INERRORS
  sky2: fix hang in napi_disable
  sky2: enforce minimum ring size
  bonding: Don't allow mode change via sysfs with slaves present
  f_phonet: fix page offset of first received fragment
  stmmac: fix pm functions avoiding sleep on spinlock
  stmmac: remove spin_lock in stmmac_ioctl.
  stmmac: parameters auto-tuning through HW cap reg
  stmmac: fix advertising 1000Base capabilties for non GMII iface
  stmmac: use mdelay on timeout of sw reset
  sky2: version 1.30
  sky2: used fixed RSS key
  sky2: reduce default Tx ring size
  sky2: rename up/down functions
  sky2: pci posting issues
  sky2: fix hang on shutdown (and other irq issues)
  r6040: fix check against MCRO_HASHEN bit in r6040_multicast_list
  MAINTAINERS: change email address for shemminger
  pch_gbe: Move #include of module.h
  ...

* 'kvm-updates/3.2' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM guest: prevent tracing recursion with kvmclock
  Revert "KVM: PPC: Add support for explicit HIOR setting"
  KVM: VMX: Check for automatic switch msr table overflow
  KVM: VMX: Add support for guest/host-only profiling
  KVM: VMX: add support for switching of PERF_GLOBAL_CTRL
  KVM: s390: announce SYNC_MMU
  KVM: s390: Fix tprot locking
  KVM: s390: handle SIGP sense running intercepts
  KVM: s390: Fix RUNNING flag misinterpretation

* 'fixes' of http://ftp.arm.linux.org.uk/pub/linux/arm/kernel/git-cur/linux-2.6-arm:
  ARM: wire up process_vm_writev and process_vm_readv syscalls
  ARM: 7160/1: setup: avoid overflowing {elf,arch}_name from proc_info_list
  ARM: 7158/1: add new MFP implement for NUC900
  ARM: 7157/1: fix a building WARNING for nuc900
  ARM: 7156/1: l2x0: fix compile error on !CONFIG_USE_OF
  ARM: 7155/1: arch.h: Declare 'pt_regs' locally
  ARM: 7154/1: mach-bcmring: fix build error in dma.c
  ARM: 7153/1: mach-bcmring: fix build error in core.c
  ARM: 7152/1: distclean: Remove generated .dtb files
  ARM: 7150/1: Allow kernel unaligned accesses on ARMv6+ processors
  ARM: 7149/1: spi/pl022: Enable clock in probe
  Revert "ARM: 7098/1: kdump: copy kernel relocation code at the kexec prepare stage"

* 'pm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  PM / Suspend: Fix bug in suspend statistics update
  PM / Hibernate: Fix the early termination of test modes
  PM / shmobile: Fix build of sh7372_pm_init() for CONFIG_PM unset
  PM Sleep: Do not extend wakeup paths to devices with ignore_children set
  PM / driver core: disable device's runtime PM during shutdown
  PM / devfreq: correct Kconfig dependency
  PM / devfreq: fix use after free in devfreq_remove_device
  PM / shmobile: Avoid restoring the INTCS state during initialization
  PM / devfreq: Remove compiler error after irq.h update
  PM / QoS: Properly use the WARN() macro in dev_pm_qos_add_request()
  PM / Clocks: Only disable enabled clocks in pm_clk_suspend()
  ARM: mach-shmobile: sh7372 A3SP no_suspend_console fix
  PM / shmobile: Don't skip debugging output in pd_power_up()

We've been hitting BUG()'s in btrfs_cont_expand and btrfs_fallocate and anywhere
else that calls btrfs_get_extent while running xfstests 13 in a loop.  This is
because fiemap is calling btrfs_get_extent with non-sectorsize aligned offsets,
which will end up adding mappings that are not sectorsize aligned, which will
cause problems in some cases for subsequent calls to btrfs_get_extent for
similar areas that are sectorsize aligned.  With this patch I ran xfstests 13 in
a loop for a couple of hours and didn't hit the problem that I could previously
hit in at most 20 minutes.  Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>

When doing the io_ctl helpers to clean up the free space cache stuff I stopped
using our normal prepare_pages stuff, which means I of course forgot to do
things like set the pages extent mapped, which will cause us all sorts of
wonderful propblems.  Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>