Commit Graph

27832 Commits

Author SHA1 Message Date
Jean-Christophe PLAGNIOL-VILLARD
770d7c39af of/mtd/nand: add generic bindings and helpers
- nand-ecc-mode : String, operation mode of the NAND ecc mode.
  Supported values are: "none", "soft", "hw", "hw_syndrome", "hw_oob_first",
  "soft_bch".
- nand-bus-width : 8 or 16 bus width if not present 8
- nand-on-flash-bbt: boolean to enable on flash bbt option if not present false

Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Stefan Roese <sr@denx.de>
2012-03-15 23:28:19 +08:00
Jean-Christophe PLAGNIOL-VILLARD
fa4d34ccd0 of: introduce helper to manage boolean
of_property_read_bool

Search for a property in a device node.
Returns true if the property exist false otherwise.

Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Acked-by: Rob Herring <rob.herring@calxeda.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
2012-03-15 23:27:31 +08:00
Jean-Christophe PLAGNIOL-VILLARD
3dcb7ea137 mtd/atmel_nand: add on_flash_bbt to enable the use of On Flash BBT
This will allow to enable it from the board.

Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Acked-by: David Woodhouse <dwmw2@infradead.org>
2012-03-15 23:27:21 +08:00
Jean-Christophe PLAGNIOL-VILLARD
bf4289cba0 ATMEL: fix nand ecc support
So we can now choose for the board the ecc mode (ecc soft, soft bch, no ecc
and hardware).

Set ecc mode in the boards to soft as currently in the driver.

Move platform data to a common header
include/linux/platform_data/atmel_nand.h

Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Acked-by: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Acked-by: David Woodhouse <dwmw2@infradead.org>
2012-03-15 23:26:32 +08:00
Nicolas Ferre
8e315a7b0c ARM: at91/tc/clocksource: Add 32 bit variant to Timer Counter
Some SoC have a 32 bit variant of Timer Counter Blocks. We do not
need the chaining of two 16 bit counters anymore for them.

The SoC nature is deduced from the device tree "compatible" string.
For non-device-tree configurations, backward compatibility is maintained
by using the default 16 bit counter configuration.

This patch addresses both the atmel_tclib and its user: tcb_clksrc
clocksource.

Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
2012-03-01 13:38:49 +01:00
Nicolas Ferre
89d4a1753b Merge branch 'irqdomain/next' of git://git.secretlab.ca/git/linux-2.6 2012-03-01 13:26:51 +01:00
Arnd Bergmann
7eca30aef7 Merge branch 'at91-3.4-base2+cleanup' of git://github.com/at91linux/linux-at91 into at91/staging/base2+cleanup
* 'at91-3.4-base2+cleanup' of git://github.com/at91linux/linux-at91: (20 commits)
  ARM: at91: properly sort dtb files in Makefile.boot
  ARM: at91: add at91sam9g25ek.dts in Makefile.boot
  ARM: at91/board-dt: drop default console
  Atmel: move console default platform_device to serial driver
  ARM: at91: merge SRAM Memory banks thanks to mirroring
  ARM: at91: finally drop at91_sys_read/write
  ARM: at91/rtc-at91sam9: pass the GPBR to use via resources
  ARM: at91:rtc/rtc-at91sam9: ioremap register bank
  ARM: at91/rtc-at91sam9: each SoC can select the RTT device to use
  ARM: at91/PMC: make register base soc independent
  ARM: at91/PMC: move assignment out of printf
  ARM: at91/pm_slowclock: add runtime detection of memory contoller
  ARM: at91: make sdram/ddr register base soc independent
  ARM: at91: move at91rm9200 sdramc defines to at91rm9200_sdramc.h
  ARM: at91/pm_slowclock: function slow_clock() accepts parameters
  ARM: at91/pm_slowclock: rename register to named define
  ARM: at91/ST: remove not needed casts
  ARM: at91: make ST (System Timer) soc independent
  ARM: at91: make matrix register base soc independent
  ARM: at91/at91x40: remove use of at91_sys_read/write

Based on top of the at91/9x5, rmk/for-armsoc, at91/device-board,
at91/pm_cleanup and at91/base.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2012-02-29 12:03:08 +00:00
Grant Likely
964dba2834 devicetree: Add empty of_platform_populate() for !CONFIG_OF_ADDRESS (sparc)
Sparc has its own helpers for translating address ranges when the device
tree is parsed at boot time, and it isn't able to use of_platform_populate().
However, there are some device drivers that want to use that function on
other DT enabled platforms (ie. TWL4030).  This patch adds an empty
of_platform_populate() implementation that returns an error when
CONFIG_OF_ADDRESS is not selected.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Benoit Cousson <b-cousson@ti.com>
Cc: Samuel Ortiz <sameo@linux.intel.com>
2012-02-26 16:48:06 -07:00
Grant Likely
d593f25ff2 irq_domain: Centralize definition of irq_dispose_mapping()
Several architectures define their own empty irq_dispose_mapping().  Since
the irq_domain code is centralized now, there is little need to do so.  This
patch removes them and creates a new empty copy when !CONFIG_IRQ_DOMAIN is
selected.

The patch also means that IRQ_DOMAIN becomes selectable on all architectures.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: sparclinux@vger.kernel.org
Cc: linux@lists.openrisc.net
2012-02-26 16:48:06 -07:00
Grant Likely
a18dc81bf5 irq_domain: constify irq_domain_ops
Make irq_domain_ops pointer a constant to make it safer for multiple
instances to share the same ops pointer and change the irq_domain code
so that it does not modify the ops.

v4: Fix mismatched type reference in powerpc code

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Milton Miller <miltonm@bga.com>
Tested-by: Olof Johansson <olof@lixom.net>
2012-02-16 06:11:24 -07:00
Grant Likely
16b2e6e2f3 irq_domain: Create common xlate functions that device drivers can use
Rather than having each interrupt controller driver creating its own barely
unique .xlate function for irq_domain, create a library of translators which
any driver can use directly.

v5: - Remove irq_domain_xlate_pci().  It was incorrect.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Mark Salter <msalter@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Milton Miller <miltonm@bga.com>
Tested-by: Olof Johansson <olof@lixom.net>
2012-02-16 06:11:23 -07:00
Grant Likely
6b783f7c5d irq_domain: Remove irq_domain_add_simple()
irq_domain_add_simple() was a stop-gap measure until complete irq_domain
support was complete.  This patch removes the irq_domain_add_simple()
interface.

This patch also drops the explicit irq_domain initialization performed
by the mach-versatile code because the versatile interrupt controller
already has irq_domain support built into it.  This was a bug that was
hanging around quietly for a while, but with the full irq_domain which
actually verifies that irq_domain ranges are available it would cause
the registration to fail and the system wouldn't boot.

v4: Fixed number of irqs in mx5 gpio code
v2: Updated to pass in host_data pointer on irq_domain allocation.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Milton Miller <miltonm@bga.com>
Cc: Russell King <linux@arm.linux.org.uk>
Tested-by: Olof Johansson <olof@lixom.net>
2012-02-16 06:11:23 -07:00
Grant Likely
75294957be irq_domain: Remove 'new' irq_domain in favour of the ppc one
This patch removes the simplistic implementation of irq_domains and enables
the powerpc infrastructure for all irq_domain users.  The powerpc
infrastructure includes support for complex mappings between Linux and
hardware irq numbers, and can manage allocation of irq_descs.

This patch also converts the few users of irq_domain_add()/irq_domain_del()
to call irq_domain_add_legacy() instead.

v3: Fix bug that set up too many irqs in translation range.
v2: Fix removal of irq_alloc_descs() call in gic driver

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Milton Miller <miltonm@bga.com>
Tested-by: Olof Johansson <olof@lixom.net>
2012-02-16 06:11:23 -07:00
Grant Likely
a850a75544 of/address: add empty static inlines for !CONFIG_OF
As the title says, this patch adds empty implementations for the address
translation functions so that they can be used when CONFIG_OF is disabled.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Rob Herring <rob.herring@calxeda.com>
2012-02-16 06:11:23 -07:00
Grant Likely
1bc04f2cf8 irq_domain: Add support for base irq and hwirq in legacy mappings
Add support for a legacy mapping where irq = (hwirq - first_hwirq + first_irq)
so that a controller driver can allocate a fixed range of irq_descs and use
a simple calculation to translate back and forth between linux and hw irq
numbers.  This is needed to use an irq_domain with many of the ARM interrupt
controller drivers that manage their own irq_desc allocations.  Ultimately
the goal is to migrate those drivers to use the linear revmap, but doing it
this way allows each driver to be converted separately which makes the
migration path easier.

This patch generalizes the IRQ_DOMAIN_MAP_LEGACY method to use
(first_irq-first_hwirq) as the offset between hwirq and linux irq number,
and adds checks to make sure that the hwirq number does not exceed range
assigned to the controller.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Milton Miller <miltonm@bga.com>
Tested-by: Olof Johansson <olof@lixom.net>
2012-02-16 06:11:23 -07:00
Grant Likely
a8db8cf0d8 irq_domain: Replace irq_alloc_host() with revmap-specific initializers
Each revmap type has different arguments for setting up the revmap.
This patch splits up the generator functions so that each revmap type
can do its own setup and the user doesn't need to keep track of how
each revmap type handles the arguments.

This patch also adds a host_data argument to the generators.  There are
cases where the host_data pointer will be needed before the function returns.
ie. the legacy map calls the .map callback for each irq before returning.

v2: - Add void *host_data argument to irq_domain_add_*() functions
    - fixed failure to compile
    - Moved IRQ_DOMAIN_MAP_* defines into irqdomain.c

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Milton Miller <miltonm@bga.com>
Tested-by: Olof Johansson <olof@lixom.net>
2012-02-16 06:11:22 -07:00
Grant Likely
cc79ca691c irq_domain: Move irq_domain code from powerpc to kernel/irq
This patch only moves the code.  It doesn't make any changes, and the
code is still only compiled for powerpc.  Follow-on patches will generalize
the code for other architectures.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Milton Miller <miltonm@bga.com>
Tested-by: Olof Johansson <olof@lixom.net>
2012-02-16 01:37:49 -07:00
Grant Likely
7bb69bade0 irq_domain: Make irq_domain structure match powerpc's irq_host
Part of the series to unify the irq remapping mechanisms in the
kernel.  A follow up patch will copy the powerpc implementation into
kernel/irq/irqdomain.c, which will be a lot easier if the structures
are identical.

Where they differ, I've chose to use the powerpc names since there is
a lot more code using those names.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Milton Miller <miltonm@bga.com>
Tested-by: Olof Johansson <olof@lixom.net>
2012-02-14 14:06:48 -07:00
Linus Torvalds
3ec1e88b33 Merge branch 'for-linus' of git://git.kernel.dk/linux-block
Says Jens:

 "Time to push off some of the pending items.  I really wanted to wait
  until we had the regression nailed, but alas it's not quite there yet.
  But I'm very confident that it's "just" a missing expire on exit, so
  fix from Tejun should be fairly trivial.  I'm headed out for a week on
  the slopes.

  - Killing the barrier part of mtip32xx.  It doesn't really support
    barriers, and it doesn't need them (writes are fully ordered).

  - A few fixes from Dan Carpenter, preventing overflows of integer
    multiplication.

  - A fixup for loop, fixing a previous commit that didn't quite solve
    the partial read problem from Dave Young.

  - A bio integer overflow fix from Kent Overstreet.

  - Improvement/fix of the door "keep locked" part of the cdrom shared
    code from Paolo Benzini.

  - A few cfq fixes from Shaohua Li.

  - A fix for bsg sysfs warning when removing a file it did not create
    from Stanislaw Gruszka.

  - Two fixes for floppy from Vivek, preventing a crash.

  - A few block core fixes from Tejun.  One killing the over-optimized
    ioc exit path, cleaning that up nicely.  Two others fixing an oops
    on elevator switch, due to calling into the scheduler merge check
    code without holding the queue lock."

* 'for-linus' of git://git.kernel.dk/linux-block:
  block: fix lockdep warning on io_context release put_io_context()
  relay: prevent integer overflow in relay_open()
  loop: zero fill bio instead of return -EIO for partial read
  bio: don't overflow in bio_get_nr_vecs()
  floppy: Fix a crash during rmmod
  floppy: Cleanup disk->queue before caling put_disk() if add_disk() was never called
  cdrom: move shared static to cdrom_device_info
  bsg: fix sysfs link remove warning
  block: don't call elevator callbacks for plug merges
  block: separate out blk_rq_merge_ok() and blk_try_merge() from elevator functions
  mtip32xx: removed the irrelevant argument of mtip_hw_submit_io() and the unused member of struct driver_data
  block: strip out locking optimization in put_io_context()
  cdrom: use copy_to_user() without the underscores
  block: fix ioc locking warning
  block: fix NULL icq_cache reference
  block,cfq: change code order
2012-02-11 10:07:11 -08:00
Linus Torvalds
8df54d622a Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Quoth David:

1) GRO MAC header comparisons were ethernet specific, breaking other
   link types.  This required a multi-faceted fix to cure the originally
   noted case (Infiniband), because IPoIB was lying about it's actual
   hard header length.  Thanks to Eric Dumazet, Roland Dreier, and
   others.

2) Fix build failure when INET_UDP_DIAG is built in and ipv6 is modular.
   From Anisse Astier.

3) Off by ones and other bug fixes in netprio_cgroup from Neil Horman.

4) ipv4 TCP reset generation needs to respect any network interface
   binding from the socket, otherwise route lookups might give a
   different result than all the other segments received.  From Shawn
   Lu.

5) Fix unintended regression in ipv4 proxy ARP responses, from Thomas
   Graf.

6) Fix SKB under-allocation bug in sh_eth, from Yoshihiro Shimoda.

7) Revert skge PCI mapping changes that are causing crashes for some
   folks, from Stephen Hemminger.

8) IPV4 route lookups fill in the wildcarded fields of the given flow
   lookup key passed in, which is fine most of the time as this is
   exactly what the caller's want.  However there are a few cases that
   want to retain the original flow key values afterwards, so handle
   those cases properly.  Fix from Julian Anastasov.

9) IGB/IXGBE VF lookup bug fixes from Greg Rose.

10) Properly null terminate filename passed to ethtool flash device
    method, from Ben Hutchings.

11) S3 resume fix in via-velocity from David Lv.

12) Fix double SKB free during xmit failure in CAIF, from Dmitry
    Tarnyagin.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (72 commits)
  net: Don't proxy arp respond if iif == rt->dst.dev if private VLAN is disabled
  ipv4: Fix wrong order of ip_rt_get_source() and update iph->daddr.
  netprio_cgroup: fix wrong memory access when NETPRIO_CGROUP=m
  netprio_cgroup: don't allocate prio table when a device is registered
  netprio_cgroup: fix an off-by-one bug
  bna: fix error handling of bnad_get_flash_partition_by_offset()
  isdn: type bug in isdn_net_header()
  net: Make qdisc_skb_cb upper size bound explicit.
  ixgbe: ethtool: stats user buffer overrun
  ixgbe: dcb: up2tc mapping lost on disable/enable CEE DCB state
  ixgbe: do not update real num queues when netdev is going away
  ixgbe: Fix broken dependency on MAX_SKB_FRAGS being related to page size
  ixgbe: Fix case of Tx Hang in PF with 32 VFs
  ixgbe: fix vf lookup
  igb: fix vf lookup
  e1000: add dropped DMA receive enable back in for WoL
  gro: more generic L2 header check
  IPoIB: Stop lying about hard_header_len and use skb->cb to stash LL addresses
  zd1211rw: firmware needs duration_id set to zero for non-pspoll frames
  net: enable TC35815 for MIPS again
  ...
2012-02-10 14:18:46 -08:00
Linus Torvalds
af5feae3d7 Merge tag 'writeback-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux
fix 1 mysterious divide error
fix 3 NULL dereference bugs in writeback tracing, on SD card removal w/o umount

* tag 'writeback-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux:
  writeback: fix dereferencing NULL bdi->dev on trace_writeback_queue
  lib: proportion: lower PROP_MAX_SHIFT to 32 on 64-bit kernel
  writeback: fix NULL bdi->dev in trace writeback_single_inode
  backing-dev: fix wakeup timer races with bdi_unregister()
2012-02-10 09:05:52 -08:00
Linus Torvalds
fe250923bb Merge tag 'usb-3.3-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
USB fixes for 3.3-rc3

Here are a few minor USB fixes and a bunch of device id updates for the
USB drivers.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

* tag 'usb-3.3-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
  USB: usbserial: add new PID number (0xa951) to the ftdi driver
  usb: ch9.h: usb_endpoint_maxp() uses __le16_to_cpu()
  usb: musb: fix a build error on mips
  uwb & wusb & usb wireless controllers: fix kconfig error & build errors
  usb: Skip PCI USB quirk handling for Netlogic XLP
  powerpc/usb: fix issue of CPU halt when missing USB PHY clock
  usb: otg: mv_otg: Add dependence
  usb: host: Distinguish Kconfig text for Freescale controllers
  USB: add new zte 3g-dongle's pid to option.c
  usb: ch9.h: usb_endpoint_maxp() uses __le16_to_cpu()
  USB: qcserial: don't enable autosuspend
  USB: qcserial: add several new serial devices
  usb: otg: mv_otg: Add dependence
  usb: gadget: zero: fix bug in loopback autoresume handling
2012-02-09 13:50:54 -08:00
Paolo Bonzini
cdccaa9467 cdrom: move shared static to cdrom_device_info
The keeplocked variable in the cdrom driver is shared across multiple
drives, but set in per-device ioctls.  Move it to the per-device struct,
avoiding that the setting on one drive affects the driver's behavior
when closing another.

[ Impact: limit udev's confusion to one drive when a CD burning program
  unlocks the CD door at the end of burning. ]

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-02-08 20:03:14 +01:00
Tejun Heo
07c2bd3735 block: don't call elevator callbacks for plug merges
Plug merge calls two elevator callbacks outside queue lock -
elevator_allow_merge_fn() and elevator_bio_merged_fn().  Although
attempt_plug_merge() suggests that elevator is guaranteed to be there
through the existing request on the plug list, nothing prevents plug
merge from calling into dying or initializing elevator.

For regular merges, bypass ensures elvpriv count to reach zero, which
in turn prevents merges as all !ELVPRIV requests get REQ_SOFTBARRIER
from forced back insertion.  Plug merge doesn't check ELVPRIV, and, as
the requests haven't gone through elevator insertion yet, it doesn't
have SOFTBARRIER set allowing merges on a bypassed queue.

This, for example, leads to the following crash during elevator
switch.

 BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
 IP: [<ffffffff813b34e9>] cfq_allow_merge+0x49/0xa0
 PGD 112cbc067 PUD 115d5c067 PMD 0
 Oops: 0000 [#1] PREEMPT SMP
 CPU 1
 Modules linked in: deadline_iosched

 Pid: 819, comm: dd Not tainted 3.3.0-rc2-work+ #76 Bochs Bochs
 RIP: 0010:[<ffffffff813b34e9>]  [<ffffffff813b34e9>] cfq_allow_merge+0x49/0xa0
 RSP: 0018:ffff8801143a38f8  EFLAGS: 00010297
 RAX: 0000000000000000 RBX: ffff88011817ce28 RCX: ffff880116eb6cc0
 RDX: 0000000000000000 RSI: ffff880118056e20 RDI: ffff8801199512f8
 RBP: ffff8801143a3908 R08: 0000000000000000 R09: 0000000000000000
 R10: 0000000000000001 R11: 0000000000000000 R12: ffff880118195708
 R13: ffff880118052aa0 R14: ffff8801143a3d50 R15: ffff880118195708
 FS:  00007f19f82cb700(0000) GS:ffff88011fc80000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
 CR2: 0000000000000008 CR3: 0000000112c6a000 CR4: 00000000000006e0
 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
 Process dd (pid: 819, threadinfo ffff8801143a2000, task ffff880116eb6cc0)
 Stack:
  ffff88011817ce28 ffff880118195708 ffff8801143a3928 ffffffff81391bba
  ffff88011817ce28 ffff880118195708 ffff8801143a3948 ffffffff81391bf1
  ffff88011817ce28 0000000000000000 ffff8801143a39a8 ffffffff81398e3e
 Call Trace:
  [<ffffffff81391bba>] elv_rq_merge_ok+0x4a/0x60
  [<ffffffff81391bf1>] elv_try_merge+0x21/0x40
  [<ffffffff81398e3e>] blk_queue_bio+0x8e/0x390
  [<ffffffff81396a5a>] generic_make_request+0xca/0x100
  [<ffffffff81396b04>] submit_bio+0x74/0x100
  [<ffffffff811d45c2>] __blockdev_direct_IO+0x1ce2/0x3450
  [<ffffffff811d0dc7>] blkdev_direct_IO+0x57/0x60
  [<ffffffff811460b5>] generic_file_aio_read+0x6d5/0x760
  [<ffffffff811986b2>] do_sync_read+0xe2/0x120
  [<ffffffff81199345>] vfs_read+0xc5/0x180
  [<ffffffff81199501>] sys_read+0x51/0x90
  [<ffffffff81aeac12>] system_call_fastpath+0x16/0x1b

There are multiple ways to fix this including making plug merge check
ELVPRIV; however,

* Calling into elevator outside queue lock is confusing and
  error-prone.

* Requests on plug list aren't known to the elevator.  They aren't on
  the elevator yet, so there's no elevator specific state to update.

* Given the nature of plug merges - collecting bio's for the same
  purpose from the same issuer - elevator specific restrictions aren't
  applicable.

So, simply don't call into elevator methods from plug merge by moving
elv_bio_merged() from bio_attempt_*_merge() to blk_queue_bio(), and
using blk_try_merge() in attempt_plug_merge().

This is based on Jens' patch to skip elevator_allow_merge_fn() from
plug merge.

Note that this makes per-cgroup merged stats skip plug merging.

Signed-off-by: Tejun Heo <tj@kernel.org>
LKML-Reference: <4F16F3CA.90904@kernel.dk>
Original-patch-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-02-08 09:19:42 +01:00
Tejun Heo
050c8ea80e block: separate out blk_rq_merge_ok() and blk_try_merge() from elevator functions
blk_rq_merge_ok() is the elevator-neutral part of merge eligibility
test.  blk_try_merge() determines merge direction and expects the
caller to have tested elv_rq_merge_ok() previously.

elv_rq_merge_ok() now wraps blk_rq_merge_ok() and then calls
elv_iosched_allow_merge().  elv_try_merge() is removed and the two
callers are updated to call elv_rq_merge_ok() explicitly followed by
blk_try_merge().  While at it, make rq_merge_ok() functions return
bool.

This is to prepare for plug merge update and doesn't introduce any
behavior change.

This is based on Jens' patch to skip elevator_allow_merge_fn() from
plug merge.

Signed-off-by: Tejun Heo <tj@kernel.org>
LKML-Reference: <4F16F3CA.90904@kernel.dk>
Original-patch-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-02-08 09:19:38 +01:00