Extend queue bypassing such that dying queue is always bypassing and
blk-throttle is drained on bypass.  With blkcg policies updated to
test blk_queue_bypass() instead of blk_queue_dead(), this ensures that
no bio or request is held by or going through blkcg policies on a
bypassing queue.

This will be used to implement blkg cleanup on elevator switches and
policy changes.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Rename and extend elv_queisce_start/end() to
blk_queue_bypass_start/end() which are exported and supports nesting
via @q->bypass_depth.  Also add blk_queue_bypass() to test bypass
state.

This will be further extended and used for blkio_group management.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

elevator_ops->elevator_init_fn() has a weird return value.  It returns
a void * which the caller should assign to q->elevator->elevator_data
and %NULL return denotes init failure.

Update such that it returns integer 0/-errno and sets elevator_data
directly as necessary.

This makes the interface more conventional and eases further cleanup.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Elevator switch tries hard to keep as much as context until new
elevator is ready so that it can revert to the original state if
initializing the new elevator fails for some reason.  Unfortunately,
with more auxiliary contexts to manage, this makes elevator init and
exit paths too complex and fragile.

This patch makes elevator_switch() unregister the current elevator and
flush icq's before start initializing the new one.  As we still keep
the old elevator itself, the only difference is that we lose icq's on
rare occassions of switching failure, which isn't critical at all.

Note that this makes explicit elevator parameter to
elevator_init_queue() and __elv_register_queue() unnecessary as they
always can use the current elevator.

This patch enables block cgroup cleanups.

-v2: blk_add_trace_msg() prints elevator name from @new_e instead of
     @e->type as the local variable no longer exists.  This caused
     build failure on CONFIG_BLK_DEV_IO_TRACE.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

cfq has been registering zeroed blkio_poilcy_cfq if CFQ_GROUP_IOSCHED
is disabled.  This fortunately doesn't collide with blk-throtl as
BLKIO_POLICY_PROP is zero but is unnecessary and risky.  Just don't
register it if not enabled.
Signed-off-by: NTejun Heo <tj@kernel.org>
Acked-by: NVivek Goyal <vgoyal@redhat.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Block cgroup core can be built as module; however, it isn't too useful
as blk-throttle can only be built-in and cfq-iosched is usually the
default built-in scheduler.  Scheduled blkcg cleanup requires calling
into blkcg from block core.  To simplify that, disallow building blkcg
as module by making CONFIG_BLK_CGROUP bool.

If building blkcg core as module really matters, which I doubt, we can
revisit it after blkcg API cleanup.

-v2: Vivek pointed out that IOSCHED_CFQ was incorrectly updated to
     depend on BLK_CGROUP.  Fixed.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Currently, blk_cleanup_queue() doesn't call elv_drain_elevator() if
q->elevator doesn't exist; however, bio based drivers don't have
elevator initialized but can still use blk-throttle.  This patch moves
q->elevator test inside blk_drain_queue() such that only
elv_drain_elevator() is skipped if !q->elevator.

-v2: loop can have registered queue which has NULL request_fn.  Make
     sure we don't call into __blk_run_queue() in such cases.
Signed-off-by: NTejun Heo <tj@kernel.org>
Reported-by: NVivek Goyal <vgoyal@redhat.com>

Fold in bug fix from Vivek.
Signed-off-by: NJens Axboe <axboe@kernel.dk>

"mem" is type u8.  We need parenthesis here or it screws up the pointer
math probably leading to an oops.
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Cc: stable@kernel.org
Acked-by: NJeff Garzik <jgarzik@redhat.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

This patch (as1519) fixes a bug in the block layer's disk-events
polling.  The polling is done by a work routine queued on the
system_nrt_wq workqueue.  Since that workqueue isn't freezable, the
polling continues even in the middle of a system sleep transition.

Obviously, polling a suspended drive for media changes and such isn't
a good thing to do; in the case of USB mass-storage devices it can
lead to real problems requiring device resets and even re-enumeration.

The patch fixes things by creating a new system-wide, non-reentrant,
freezable workqueue and using it for disk-events polling.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
CC: <stable@kernel.org>
Acked-by: NTejun Heo <tj@kernel.org>
Acked-by: NRafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Set CommandMailbox with memset before use it. Fix for:

drivers/block/DAC960.c: In function ‘DAC960_V1_EnableMemoryMailboxInterface’:
arch/x86/include/asm/io.h:61:1: warning: ‘CommandMailbox.Bytes[12]’
 may be used uninitialized in this function [-Wuninitialized]
drivers/block/DAC960.c:1175:30: note: ‘CommandMailbox.Bytes[12]’
 was declared here
Signed-off-by: NDanny Kukawka <danny.kukawka@bisect.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Fixed compiler warning:

comparison between ‘DAC960_V2_IOCTL_Opcode_T’ and ‘enum <anonymous>’

Renamed enum, added a new enum for SCSI_10.CommandOpcode in
DAC960_V2_ProcessCompletedCommand().
Signed-off-by: NDanny Kukawka <danny.kukawka@bisect.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

The following situation might occur:

__blkdev_get:			add_disk:

				register_disk()
get_gendisk()

disk_block_events()
	disk->ev == NULL

				disk_add_events()

__disk_unblock_events()
	disk->ev != NULL
	--ev->block

Then we unblock events, when they are suppose to be blocked. This can
trigger events related block/genhd.c warnings, but also can crash in
sd_check_events() or other places.

I'm able to reproduce crashes with the following scripts (with
connected usb dongle as sdb disk).

<snip>
DEV=/dev/sdb
ENABLE=/sys/bus/usb/devices/1-2/bConfigurationValue

function stop_me()
{
	for i in `jobs -p` ; do kill $i 2> /dev/null ; done
	exit
}

trap stop_me SIGHUP SIGINT SIGTERM

for ((i = 0; i < 10; i++)) ; do
	while true; do fdisk -l $DEV  2>&1 > /dev/null ; done &
done

while true ; do
echo 1 > $ENABLE
sleep 1
echo 0 > $ENABLE
done
</snip>

I use the script to verify patch fixing oops in sd_revalidate_disk
http://marc.info/?l=linux-scsi&m=132935572512352&w=2
Without Jun'ichi Nomura patch titled "Fix NULL pointer dereference in
sd_revalidate_disk" or this one, script easily crash kernel within
a few seconds. With both patches applied I do not observe crash.
Unfortunately after some time (dozen of minutes), script will hung in:

[ 1563.906432]  [<c08354f5>] schedule_timeout_uninterruptible+0x15/0x20
[ 1563.906437]  [<c04532d5>] msleep+0x15/0x20
[ 1563.906443]  [<c05d60b2>] blk_drain_queue+0x32/0xd0
[ 1563.906447]  [<c05d6e00>] blk_cleanup_queue+0xd0/0x170
[ 1563.906454]  [<c06d278f>] scsi_free_queue+0x3f/0x60
[ 1563.906459]  [<c06d7e6e>] __scsi_remove_device+0x6e/0xb0
[ 1563.906463]  [<c06d4aff>] scsi_forget_host+0x4f/0x60
[ 1563.906468]  [<c06cd84a>] scsi_remove_host+0x5a/0xf0
[ 1563.906482]  [<f7f030fb>] quiesce_and_remove_host+0x5b/0xa0 [usb_storage]
[ 1563.906490]  [<f7f03203>] usb_stor_disconnect+0x13/0x20 [usb_storage]

Anyway I think this patch is some step forward.

As drawback, I do not teardown on sysfs file create error, because I do
not know how to nullify disk->ev (since it can be used). However add_disk
error handling practically does not exist too, and things will work
without this sysfs file, except events will not be exported to user
space.
Signed-off-by: NStanislaw Gruszka <sgruszka@redhat.com>
Acked-by: NTejun Heo <tj@kernel.org>
Cc: stable@kernel.org
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Fix setting bio flags in drivers (sd_dif/floppy).
Signed-off-by: NMuthukumar R <muthur@gmail.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Since 2.6.39 (1196f8b8), when a driver returns -ENOMEDIUM for open(),
__blkdev_get() calls rescan_partitions() to remove
in-kernel partition structures and raise KOBJ_CHANGE uevent.

However it ends up calling driver's revalidate_disk without open
and could cause oops.

In the case of SCSI:

  process A                  process B
  ----------------------------------------------
  sys_open
    __blkdev_get
      sd_open
        returns -ENOMEDIUM
                             scsi_remove_device
                               <scsi_device torn down>
      rescan_partitions
        sd_revalidate_disk
          <oops>
Oopses are reported here:
http://marc.info/?l=linux-scsi&m=132388619710052

This patch separates the partition invalidation from rescan_partitions()
and use it for -ENOMEDIUM case.
Reported-by: NHuajun Li <huajun.li.lee@gmail.com>
Signed-off-by: NJun'ichi Nomura <j-nomura@ce.jp.nec.com>
Acked-by: NTejun Heo <tj@kernel.org>
Cc: stable@kernel.org
Signed-off-by: NJens Axboe <axboe@kernel.dk>

While updating locking, b2efa052 "block, cfq: unlink
cfq_io_context's immediately" moved elevator_exit_icq_fn() invocation
from exit_io_context() to the final ioc put.  While this doesn't cause
catastrophic failure, it effectively removes task exit notification to
elevator and cause noticeable IO performance degradation with CFQ.

On task exit, CFQ used to immediately expire the slice if it was being
used by the exiting task as no more IO would be issued by the task;
however, after b2efa052, the notification is lost and disk could sit
idle needlessly, leading to noticeable IO performance degradation for
certain workloads.

This patch renames ioc_exit_icq() to ioc_destroy_icq(), separates
elevator_exit_icq_fn() invocation into ioc_exit_icq() and invokes it
from exit_io_context().  ICQ_EXITED flag is added to avoid invoking
the callback more than once for the same icq.

Walking icq_list from ioc side and invoking elevator callback requires
reverse double locking.  This may be better implemented using RCU;
unfortunately, using RCU isn't trivial.  e.g. RCU protection would
need to cover request_queue and queue_lock switch on cleanup makes
grabbing queue_lock from RCU unsafe.  Reverse double locking should
do, at least for now.
Signed-off-by: NTejun Heo <tj@kernel.org>
Reported-and-bisected-by: NShaohua Li <shli@kernel.org>
LKML-Reference: <CANejiEVzs=pUhQSTvUppkDcc2TNZyfohBRLygW5zFmXyk5A-xQ@mail.gmail.com>
Tested-by: NShaohua Li <shaohua.li@intel.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Reverse double lock dancing in ioc_release_fn() can be simplified by
just using trylock on the queue_lock and back out from ioc lock on
trylock failure.  Simplify it.
Signed-off-by: NTejun Heo <tj@kernel.org>
Tested-by: NShaohua Li <shaohua.li@intel.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

icq->changed was used for ICQ_*_CHANGED bits.  Rename it to flags and
access it under ioc->lock instead of using atomic bitops.
ioc_get_changed() is added so that the changed part can be fetched and
cleared as before.

icq->flags will be used to carry other flags.
Signed-off-by: NTejun Heo <tj@kernel.org>
Tested-by: NShaohua Li <shaohua.li@intel.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

One small bug fix from Axel plus a fix for a build failure in unrealistic
but commonly built configs which for some reason manage to survive for
an awfully long time in -next without any reports.

* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator:
  regulator: Fix getting voltage in max8649_enable_time()
  regulator: Fix mc13xxx regulator modular build (again)

Quoth BenH:
 "Here are a few powerpc fixes for 3.3, all pretty trivial.  I also
  added the patch to define GET_IP/SET_IP so we can use some more
  asm-generic goodness."

* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
  powerpc/pseries/eeh: Fix crash when error happens during device probe
  powerpc/pseries: Fix partition migration hang in stop_topology_update
  powerpc/powernv: Disable interrupts while taking phb->lock
  powerpc: Fix WARN_ON in decrementer_check_overflow
  powerpc/wsp: Fix IRQ affinity setting
  powerpc: Implement GET_IP/SET_IP
  powerpc/wsp: Permanently enable PCI class code workaround

MMC fixes for 3.3-rc4:
 * The most visible fix here is against a regression introduced in 3.3-rc1
   that ran cards in Ultra High Speed mode even when they failed to initialize
   in that mode, leading to lower-speed cards failing to mount.
 * A lockdep warning introduced in 3.3-rc1 is fixed.
 * Various other small driver fixes, most notably for a NULL dereference
   when using highmem with dw_mmc.

* tag 'mmc-fixes-for-3.3-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/cjb/mmc:
  mmc: dw_mmc: Fix PIO mode with support of highmem
  mmc: atmel-mci: save and restore sdioirq when soft reset is performed
  mmc: block: Init ro_lock sysfs attr to fix lockdep warnings
  mmc: sh_mmcif: fix late delayed work initialisation
  mmc: tmio_mmc: fix card eject during IO with DMA
  mmc: core: Fix comparison issue in mmc_compare_ext_csds
  mmc: core: Fix PowerOff Notify suspend/resume
  mmc: sdhci-pci: set Medfield SDIO as non-removable
  mmc: core: add the capability for broken voltage
  mmc: core: Fix low speed mmc card detection failure
  mmc: esdhc: set the timeout to the max value
  mmc: esdhc: add PIO mode support
  mmc: core: Ensure clocks are always enabled before host interaction
  mmc: of_mmc_spi: fix little endian support
  mmc: core: UHS sdio card that fails should not exceed 50MHz
  mmc: esdhc: fix errors when booting kernel on Freescale eSDHC version 2.3

Merge tag 'stable/for-linus-fixes-3.3-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen

Two fixes for VCPU offlining; One to fix the string format exposed
by the xen-pci[front|back] to conform to the one used in majority of
PCI drivers; Two fixes to make the code more resilient to invalid
configurations.
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

* tag 'stable/for-linus-fixes-3.3-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xenbus_dev: add missing error check to watch handling
  xen/pci[front|back]: Use %d instead of %1x for displaying PCI devfn.
  xen pvhvm: do not remap pirqs onto evtchns if !xen_have_vector_callback
  xen/smp: Fix CPU online/offline bug triggering a BUG: scheduling while atomic.
  xen/bootup: During bootup suppress XENBUS: Unable to read cpu state

sound fixes for 3.3-rc4

Basically all small fixes suited as rc4: a few HD-audio regression fixes,
a stable fix for an old Dell laptop with intel8x0, and a simple fix for
ASoC fsi.

* tag 'sound-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
  ALSA: intel8x0: Fix default inaudible sound on Gateway M520
  ALSA: hda - Fix silent speaker output on Acer Aspire 6935
  ALSA: hda - Fix initialization of secondary capture source on VT1705
  ASoC: fsi: fixup fsi_pointer() calculation method
  ALSA: hda - Fix mute-LED VREF value for new HP laptops

BugLink: https://bugs.launchpad.net/bugs/930842

The reporter states that audio is inaudible by default without muting
'External Amplifier'. Add a quirk to handle his SSID so that changing
the control is not necessary.
Reported-and-tested-by: NBenjamin Carlson <elderbubba0810@gmail.com>
Cc: <stable@kernel.org>
Signed-off-by: NDaniel T Chen <crimsun@ubuntu.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

A simple fix from Morimoto-san for the pointer() operation in the FSI
driver.

* git://git.samba.org/sfrench/cifs-2.6:
  cifs: don't return error from standard_receive3 after marking response malformed
  cifs: request oplock when doing open on lookup
  cifs: fix error handling when cifscreds key payload is an error

This updates the sha512 fix so that it doesn't cause excessive stack
usage on i386.  This is done by reverting to the original code, and
avoiding the W duplication by moving its initialisation into the loop.

As the underlying code is in fact the one that we have used for years,
I'm pushing this now instead of postponing to the next cycle.

* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  crypto: sha512 - Avoid stack bloat on i386
  crypto: sha512 - Use binary and instead of modulus

EEH may happen during a PCI driver probe. If the driver is trying to
access some register in a loop, the EEH code will try to print the
driver name. But the driver pointer in struct pci_dev is not set until
probe returns successfully.

Use a function to test if the device and the driver pointer is NULL
before accessing the driver's name.
Signed-off-by: NThadeu Lima de Souza Cascardo <cascardo@linux.vnet.ibm.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

This fixes a hang that was observed during live partition migration.
Since stop_topology_update must not be called from an interrupt
context, call it earlier in the migration process. The hang observed
can be seen below:

WARNING: at kernel/timer.c:1011
Modules linked in: ip6t_LOG xt_tcpudp xt_pkttype ipt_LOG xt_limit ip6t_REJECT nf_conntrack_ipv6 nf_defrag_ipv6 ip6table_raw xt_NOTRACK ipt_REJECT xt_state iptable_raw iptable_filter ip6table_mangle nf_conntrack_netbios_ns nf_conntrack_broadcast nf_conntrack_ipv4 nf_conntrack nf_defrag_ipv4 ip_tables ip6table_filter ip6_tables x_tables ipv6 fuse loop ibmveth sg ext3 jbd mbcache raid456 async_raid6_recov async_pq raid6_pq async_xor xor async_memcpy async_tx raid10 raid1 raid0 scsi_dh_alua scsi_dh_rdac scsi_dh_hp_sw scsi_dh_emc dm_round_robin dm_multipath scsi_dh sd_mod crc_t10dif ibmvfc scsi_transport_fc scsi_tgt scsi_mod dm_snapshot dm_mod
NIP: c0000000000c52d8 LR: c00000000004be28 CTR: 0000000000000000
REGS: c00000005ffd77d0 TRAP: 0700   Not tainted  (3.2.0-git-00001-g07d106d0)
MSR: 8000000000021032 <ME,CE,IR,DR>  CR: 48000084  XER: 00000001
CFAR: c00000000004be20
TASK = c00000005ec78860[0] 'swapper/3' THREAD: c00000005ec98000 CPU: 3
GPR00: 0000000000000001 c00000005ffd7a50 c000000000fbbc98 c000000000ec8340
GPR04: 00000000282a0020 0000000000000000 0000000000004000 0000000000000101
GPR08: 0000000000000012 c00000005ffd4000 0000000000000020 c000000000f3ba88
GPR12: 0000000000000000 c000000007f40900 0000000000000001 0000000000000004
GPR16: 0000000000000001 0000000000000000 0000000000000000 c000000001022310
GPR20: 0000000000000001 0000000000000000 0000000000200200 c000000001029e14
GPR24: 0000000000000000 0000000000000001 0000000000000040 c00000003f74bc80
GPR28: c00000003f74bc84 c000000000f38038 c000000000f16b58 c000000000ec8340
NIP [c0000000000c52d8] .del_timer_sync+0x28/0x60
LR [c00000000004be28] .stop_topology_update+0x20/0x38
Call Trace:
[c00000005ffd7a50] [c00000005ec78860] 0xc00000005ec78860 (unreliable)
[c00000005ffd7ad0] [c00000000004be28] .stop_topology_update+0x20/0x38
[c00000005ffd7b40] [c000000000028378] .__rtas_suspend_last_cpu+0x58/0x260
[c00000005ffd7bf0] [c0000000000fa230] .generic_smp_call_function_interrupt+0x160/0x358
[c00000005ffd7cf0] [c000000000036ec8] .smp_ipi_demux+0x88/0x100
[c00000005ffd7d80] [c00000000005c154] .icp_hv_ipi_action+0x5c/0x80
[c00000005ffd7e00] [c00000000012a088] .handle_irq_event_percpu+0x100/0x318
[c00000005ffd7f00] [c00000000012e774] .handle_percpu_irq+0x84/0xd0
[c00000005ffd7f90] [c000000000022ba8] .call_handle_irq+0x1c/0x2c
[c00000005ec9ba20] [c00000000001157c] .do_IRQ+0x22c/0x2a8
[c00000005ec9bae0] [c0000000000054bc] hardware_interrupt_entry+0x18/0x1c
Exception: 501 at .cpu_idle+0x194/0x2f8
    LR = .cpu_idle+0x194/0x2f8
[c00000005ec9bdd0] [c000000000017e58] .cpu_idle+0x188/0x2f8 (unreliable)
[c00000005ec9be90] [c00000000067ec18] .start_secondary+0x3e4/0x524
[c00000005ec9bf90] [c0000000000093e8] .start_secondary_prolog+0x10/0x14
Instruction dump:
ebe1fff8 4e800020 fbe1fff8 7c0802a6 f8010010 7c7f1b78 f821ff81 78290464
80090014 5400019e 7c0000d0 78000fe0 <0b000000> 4800000c 7c210b78 7c421378
Signed-off-by: NBrian King <brking@linux.vnet.ibm.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

We need to disable interrupts when taking the phb->lock. Otherwise
we could deadlock with pci_lock taken from an interrupt.
Signed-off-by: NMichael Ellerman <michael@ellerman.id.au>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

We use __get_cpu_var() which triggers a false positive warning
in smp_processor_id() thinking interrupts are enabled (at this
point, they are soft-enabled but hard-disabled).
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

We call the cache_hwirq_map() function with a linux IRQ number
but it expects a HW irq number. This triggers a BUG on multic-chip
setups in addition to not doing the right thing.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

With this change, helpers such as instruction_pointer() et al, get defined
in the generic header in terms of GET_IP

Removed the unnecessary definition of profile_pc in !CONFIG_SMP case as
suggested by Mike Frysinger.
Signed-off-by: NSrikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: NAnanth N Mavinakayanahalli <ananth@in.ibm.com>
Acked-by: NMike Frysinger <vapier@gentoo.org>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

It appears that on the Chroma card, the class code of the root
complex is still wrong even on DD2 or later chips. This could
be a firmware issue, but that breaks resource allocation so let's
unconditionally fix it up.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

Current PIO mode makes a kernel crash with CONFIG_HIGHMEM.
Highmem pages have a NULL from sg_virt(sg).
This patch fixes the following problem.

Unable to handle kernel NULL pointer dereference at virtual address 00000000
pgd = c0004000
[00000000] *pgd=00000000
Internal error: Oops: 817 [#1] PREEMPT SMP
Modules linked in:
CPU: 0    Not tainted  (3.0.15-01423-gdbf465f #589)
PC is at dw_mci_pull_data32+0x4c/0x9c
LR is at dw_mci_read_data_pio+0x54/0x1f0
pc : [<c0358824>]    lr : [<c035988c>]    psr: 20000193
sp : c0619d48  ip : c0619d70  fp : c0619d6c
r10: 00000000  r9 : 00000002  r8 : 00001000
r7 : 00000200  r6 : 00000000  r5 : e1dd3100  r4 : 00000000
r3 : 65622023  r2 : 0000007f  r1 : eeb96000  r0 : e1dd3100
Flags: nzCv  IRQs off  FIQs on  Mode SVC_32  ISA ARM  Segment
xkernel
Control: 10c5387d  Table: 61e2004a  DAC: 00000015
Process swapper (pid: 0, stack limit = 0xc06182f0)
Stack: (0xc0619d48 to 0xc061a000)
9d40:                   e1dd3100 e1a4f000 00000000 e1dd3100 e1a4f000 00000200
9d60: c0619da4 c0619d70 c035988c c03587e4 c0619d9c e18158f4 e1dd3100 e1dd3100
9d80: 00000020 00000000 00000000 00000020 c06e8a84 00000000 c0619e04 c0619da8
9da0: c0359b24 c0359844 e18158f4 e1dd3164 e1dd3168 e1dd3150 3d02fc79 e1dd3154
9dc0: e1dd3178 00000000 00000020 00000000 e1dd3150 00000000 c10dd7e8 e1a84900
9de0: c061e7cc 00000000 00000000 0000008d c06e8a84 c061e780 c0619e4c c0619e08
9e00: c00c4738 c0359a34 3d02fc79 00000000 c0619e4c c05a1698 c05a1670 c05a165c
9e20: c04de8b0 c061e780 c061e7cc e1a84900 ffffed68 0000008d c0618000 00000000
9e40: c0619e6c c0619e50 c00c48b4 c00c46c8 c061e780 c00423ac c061e7cc ffffed68
9e60: c0619e8c c0619e70 c00c7358 c00c487c 0000008d ffffee38 c0618000 ffffed68
9e80: c0619ea4 c0619e90 c00c4258 c00c72b0 c00423ac ffffee38 c0619ecc c0619ea8
9ea0: c004241c c00c4234 ffffffff f8810000 0000006d 00000002 00000001 7fffffff
9ec0: c0619f44 c0619ed0 c0048bc0 c00423c4 220ae7a9 00000000 386f0d30 0005d3a4
9ee0: c00423ac c10dd0b8 c06f2cd8 c0618000 c0594778 c003a674 7fffffff c0619f44
9f00: 386f0d30 c0619f18 c00a6f94 c005be3c 80000013 ffffffff 386f0d30 0005d3a4
9f20: 386f0d30 0005d2d1 c10dd0a8 c10dd0b8 c06f2cd8 c0618000 c0619f74 c0619f48
9f40: c0345858 c005be00 c00a2440 c0618000 c0618000 c00410d8 c06c1944 c00410fc
9f60: c0594778 c003a674 c0619f9c c0619f78 c004a7e8 c03457b4 c0618000 c06c18f8
9f80: 00000000 c0039c70 c06c18d4 c003a674 c0619fb4 c0619fa0 c04ceafc c004a714
9fa0: c06287b4 c06c18f8 c0619ff4 c0619fb8 c0008b68 c04cea68 c0008578 00000000
9fc0: 00000000 c003a674 00000000 10c5387d c0628658 c003aa78 c062f1c4 4000406a
9fe0: 413fc090 00000000 00000000 c0619ff8 40008044 c0008858 00000000 00000000
Backtrace:
[<c03587d8>] (dw_mci_pull_data32+0x0/0x9c) from [<c035988c>] (dw_mci_read_data_pio+0x54/0x1f0)
 r6:00000200 r5:e1a4f000 r4:e1dd3100
 [<c0359838>] (dw_mci_read_data_pio+0x0/0x1f0) from [<c0359b24>] (dw_mci_interrupt+0xfc/0x4a4)
[<c0359a28>] (dw_mci_interrupt+0x0/0x4a4) from [<c00c4738>] (handle_irq_event_percpu+0x7c/0x1b4)
[<c00c46bc>] (handle_irq_event_percpu+0x0/0x1b4) from [<c00c48b4>] (handle_irq_event+0x44/0x64)
[<c00c4870>] (handle_irq_event+0x0/0x64) from [<c00c7358>] (handle_fasteoi_irq+0xb4/0x124)
 r7:ffffed68 r6:c061e7cc r5:c00423ac r4:c061e780
 [<c00c72a4>] (handle_fasteoi_irq+0x0/0x124) from [<c00c4258>] (generic_handle_irq+0x30/0x38)
 r7:ffffed68 r6:c0618000 r5:ffffee38 r4:0000008d
 [<c00c4228>] (generic_handle_irq+0x0/0x38) from [<c004241c>] (asm_do_IRQ+0x64/0xe0)
 r5:ffffee38 r4:c00423ac
 [<c00423b8>] (asm_do_IRQ+0x0/0xe0) from [<c0048bc0>] (__irq_svc+0x80/0x14c)
Exception stack(0xc0619ed0 to 0xc0619f18)
Signed-off-by: NSeungwon Jeon <tgih.jun@samsung.com>
Acked-by: NWill Newton <will.newton@imgtec.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: NChris Ball <cjb@laptop.org>

Sometimes a software reset is needed. Then some registers are saved and
restored but the interrupt mask register is missing. It causes issues
with sdio devices whose interrupts are masked after reset.
Signed-off-by: NLudovic Desroches <ludovic.desroches@atmel.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: NNicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: NChris Ball <cjb@laptop.org>

Signed-off-by: NRabin Vincent <rabin.vincent@stericsson.com>
Signed-off-by: NJohan Rudholm <johan.rudholm@stericsson.com>
Signed-off-by: NUlf Hansson <ulf.hansson@stericsson.com>
Acked-by: NLinus Walleij <linus.walleij@linaro.org>
Reviewed-by: NNamjae Jeon <linkinjeon@gmail.com>
Signed-off-by: NChris Ball <cjb@laptop.org>

If the driver is loaded with a card in the slot, mmc_add_host() will
schedule an immediate card-detection work, which will start IO and wait
for command completion. Usually the kernel first returns to the sh_mmcif
probe function, lets it finish and only then schedules the rescan work.
But sometimes, expecially under heavy system load, the work will be
scheduled immediately before returning to the probe method. In this case
it is important for the driver to be fully prepared for IO. For sh_mmcif
this means, that also the timeout work has to be initialised before
calling mmc_add_host(). It is also better to prepare interrupts
beforehand. Besides, since mmc_add_host() does card-detection itself,
there is no need to do it again immediately afterwards.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NChris Ball <cjb@laptop.org>

When DMA is in use and the card is ejected during IO, DMA transfers have to
be terminated, otherwise the dmaengine driver fails to operate properly,
when the card is re-inserted.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NChris Ball <cjb@laptop.org>

Found this issue during code review. Actually, there are two issues which
both compensate together in lucky case.  In unlucky case the bus width
probing might not work as expected.
Signed-off-by: NJurgen Heeks <jurgen.heeks@nokia.com>
Reviewed-by: NNamjae Jeon <linkinjeon@gmail.com>
Signed-off-by: NChris Ball <cjb@laptop.org>

Modified the mmc_poweroff to resume before sending the poweroff
notification command. In sleep mode only AWAKE and RESET commands are
allowed, so before sending the poweroff notification command resume from
sleep mode and then send the notification command.

PowerOff Notify is tested on a Synopsis Designware Host Controller
(eMMC 4.5). The suspend to RAM and resume works fine.
Signed-off-by: NGirish K S <girish.shivananjappa@linaro.org>
Tested-by: NGirish K S <girish.shivananjappa@linaro.org>
Reviewed-by: NSaugata Das <saugata.das@linaro.org>
Signed-off-by: NChris Ball <cjb@laptop.org>