linux-toradex.git/drivers/block, branch v3.2.28

virtio-blk: Use block layer provided spinlock

2012-08-09T23:24:58+00:00

commit 2c95a3290919541b846bee3e0fbaa75860929f53 upstream.

Block layer will allocate a spinlock for the queue if the driver does
not provide one in blk_init_queue().

The reason to use the internal spinlock is that blk_cleanup_queue() will
switch to use the internal spinlock in the cleanup code path.

        if (q->queue_lock != &q->__queue_lock)
                q->queue_lock = &q->__queue_lock;

However, processes which are in D state might have taken the driver
provided spinlock, when the processes wake up, they would release the
block provided spinlock.

=====================================
[ BUG: bad unlock balance detected! ]
3.4.0-rc7+ #238 Not tainted
-------------------------------------
fio/3587 is trying to release lock (&(&q->__queue_lock)->rlock) at:
[] blk_queue_bio+0x2a2/0x380
but there are no more locks to release!

other info that might help us debug this:
1 lock held by fio/3587:
 #0:  (&(&vblk->lock)->rlock){......}, at:
[] get_request_wait+0x19a/0x250

Other drivers use block layer provided spinlock as well, e.g. SCSI.

Switching to the block layer provided spinlock saves a bit of memory and
does not increase lock contention. Performance test shows no real
difference is observed before and after this patch.

Changes in v2: Improve commit log as Michael suggested.

Cc: virtualization@lists.linux-foundation.org
Cc: kvm@vger.kernel.org
Signed-off-by: Asias He 
Acked-by: Michael S. Tsirkin 
Signed-off-by: Rusty Russell 
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings

floppy: Cleanup disk->queue before caling put_disk() if add_disk() was never called

2012-08-09T23:24:33+00:00

commit 3f9a5aabd0a9fe0e0cd308506f48963d79169aa7 upstream.

add_disk() takes gendisk reference on request queue. If driver failed during
initialization and never called add_disk() then that extra reference is not
taken. That reference is put in put_disk(). floppy driver allocates the
disk, allocates queue, sets disk->queue and then relizes that floppy
controller is not present. It tries to tear down everything and tries to
put a reference down in put_disk() which was never taken.

In such error cases cleanup disk->queue before calling put_disk() so that
we never try to put down a reference which was never taken in first place.

Reported-and-tested-by: Suresh Jayaraman 
Tested-by: Dirk Gouders 
Signed-off-by: Vivek Goyal 
Acked-by: Tejun Heo 
Signed-off-by: Jens Axboe 
Signed-off-by: Ben Hutchings

umem: fix up unplugging

2012-07-12T03:31:59+00:00

commit 32587371ad3db2f9d335de10dbd8cffd4fff5669 upstream.

Fix a regression introduced by 7eaceaccab5f40 ("block: remove per-queue
plugging").  In that patch, Jens removed the whole mm_unplug_device()
function, which used to be the trigger to make umem start to work.

We need to implement unplugging to make umem start to work, or I/O will
never be triggered.

Signed-off-by: Tao Guo 
Cc: Neil Brown 
Cc: Jens Axboe 
Cc: Shaohua Li 
Acked-by: NeilBrown 
Signed-off-by: Jens Axboe 
Signed-off-by: Ben Hutchings

cciss: Fix scsi tape io with more than 255 scatter gather elements

2012-04-22T22:31:00+00:00

commit bc67f63650fad6b3478d9ddfd5406d45a95987c9 upstream.

The total number of scatter gather elements in the CISS command
used by the scsi tape code was being cast to a u8, which can hold
at most 255 scatter gather elements.  It should have been cast to
a u16.  Without this patch the command gets rejected by the controller
since the total scatter gather count did not add up to the right
value resulting in an i/o error.

Signed-off-by: Stephen M. Cameron 
Signed-off-by: Jens Axboe 
Signed-off-by: Greg Kroah-Hartman

cciss: Initialize scsi host max_sectors for tape drive support

2012-04-22T22:31:00+00:00

commit 395d287526bb60411ff37b19ad9dd38b58ba8732 upstream.

The default is too small (1024 blocks), use h->cciss_max_sectors (8192 blocks)
Without this change, if you try to set the block size of a tape drive above
512*1024, via "mt -f /dev/st0 setblk nnn" where nnn is greater than 524288,
it won't work right.

Signed-off-by: Stephen M. Cameron 
Signed-off-by: Jens Axboe 
Signed-off-by: Greg Kroah-Hartman

block, sx8: fix pointer math issue getting fw version

2012-03-19T16:02:34+00:00

commit ea5f4db8ece896c2ab9eafa0924148a2596c52e4 upstream.

"mem" is type u8.  We need parenthesis here or it screws up the pointer
math probably leading to an oops.

Signed-off-by: Dan Carpenter 
Acked-by: Jeff Garzik 
Signed-off-by: Jens Axboe 
Signed-off-by: Greg Kroah-Hartman

block: add and use scsi_blk_cmd_ioctl

2012-01-26T00:13:42+00:00

commit 577ebb374c78314ac4617242f509e2f5e7156649 upstream.

Introduce a wrapper around scsi_cmd_ioctl that takes a block device.

The function will then be enhanced to detect partition block devices
and, in that case, subject the ioctls to whitelisting.

Cc: linux-scsi@vger.kernel.org
Cc: Jens Axboe 
Cc: James Bottomley 
Signed-off-by: Paolo Bonzini 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

Merge branch 'for-linus' of git://git.kernel.dk/linux-block

2011-12-16T18:05:14+00:00

* 'for-linus' of git://git.kernel.dk/linux-block:
  block: don't kick empty queue in blk_drain_queue()
  block/swim3: Locking fixes
  loop: Fix discard_alignment default setting
  cfq-iosched: fix cfq_cic_link() race confition
  cfq-iosched: free cic_index if blkio_alloc_blkg_stats fails
  cciss: fix flush cache transfer length
  cciss: Add IRQF_SHARED back in for the non-MSI(X) interrupt handler
  loop: fix loop block driver discard and encryption comment
  block: initialize request_queue's numa node during

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client

2011-12-13T22:59:42+00:00

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
  ceph: add missing spin_unlock at ceph_mdsc_build_path()
  ceph: fix SEEK_CUR, SEEK_SET regression
  crush: fix mapping calculation when force argument doesn't exist
  ceph: use i_ceph_lock instead of i_lock
  rbd: remove buggy rollback functionality
  rbd: return an error when an invalid header is read
  ceph: fix rasize reporting by ceph_show_options

block/swim3: Locking fixes

2011-12-12T11:42:12+00:00

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 
Signed-off-by: Jens Axboe