linux-stable.git/block/blk-settings.c, branch linux-3.17.y

block: fix alignment_offset math that assumes io_min is a power-of-2

2014-11-14T18:10:26+00:00

commit b8839b8c55f3fdd60dc36abcda7e0266aff7985c upstream.

The math in both blk_stack_limits() and queue_limit_alignment_offset()
assume that a block device's io_min (aka minimum_io_size) is always a
power-of-2.  Fix the math such that it works for non-power-of-2 io_min.

This issue (of alignment_offset != 0) became apparent when testing
dm-thinp with a thinp blocksize that matches a RAID6 stripesize of
1280K.  Commit fdfb4c8c1 ("dm thin: set minimum_io_size to pool's data
block size") unlocked the potential for alignment_offset != 0 due to
the dm-thin-pool's io_min possibly being a non-power-of-2.

Signed-off-by: Mike Snitzer 
Acked-by: Martin K. Petersen 
Signed-off-by: Jens Axboe 
Signed-off-by: Greg Kroah-Hartman

block: ensure that bio_add_page() always accepts a page for an empty bio

2014-06-10T18:53:56+00:00

With commit 762380ad9322 added support for chunk sizes and no merging
across them, it broke the rule of always allowing adding of a single
page to an empty bio. So relax the restriction a bit to allow for that,
similarly to what we have always done.

This fixes a crash with mkfs.xfs and 512b sector sizes on NVMe.

Reported-by: Keith Busch 
Signed-off-by: Jens Axboe

block: add notion of a chunk size for request merging

2014-06-05T19:38:39+00:00

Some drivers have different limits on what size a request should
optimally be, depending on the offset of the request. Similar to
dividing a device into chunks. Add a setting that allows the driver
to inform the block layer of such a chunk size. The block layer will
then prevent merging across the chunks.

This is needed to optimally support NVMe with a non-zero stripe size.

Signed-off-by: Jens Axboe

bcache/md: Use raid stripe size

2014-01-08T21:05:09+00:00

Now that we've got code for raid5/6 stripe awareness, bcache just needs
to know about the stripes and when writing partial stripes is expensive
- we probably don't want to enable this optimization for raid1 or 10,
even though they have stripes. So add a flag to queue_limits.

Signed-off-by: Kent Overstreet

Merge branch 'for-3.13/core' of git://git.kernel.dk/linux-block

2013-11-14T03:08:14+00:00

Pull block IO core updates from Jens Axboe:
 "This is the pull request for the core changes in the block layer for
  3.13.  It contains:

   - The new blk-mq request interface.

     This is a new and more scalable queueing model that marries the
     best part of the request based interface we currently have (which
     is fully featured, but scales poorly) and the bio based "interface"
     which the new drivers for high IOPS devices end up using because
     it's much faster than the request based one.

     The bio interface has no block layer support, since it taps into
     the stack much earlier.  This means that drivers end up having to
     implement a lot of functionality on their own, like tagging,
     timeout handling, requeue, etc.  The blk-mq interface provides all
     these.  Some drivers even provide a switch to select bio or rq and
     has code to handle both, since things like merging only works in
     the rq model and hence is faster for some workloads.  This is a
     huge mess.  Conversion of these drivers nets us a substantial code
     reduction.  Initial results on converting SCSI to this model even
     shows an 8x improvement on single queue devices.  So while the
     model was intended to work on the newer multiqueue devices, it has
     substantial improvements for "classic" hardware as well.  This code
     has gone through extensive testing and development, it's now ready
     to go.  A pull request is coming to convert virtio-blk to this
     model will be will be coming as well, with more drivers scheduled
     for 3.14 conversion.

   - Two blktrace fixes from Jan and Chen Gang.

   - A plug merge fix from Alireza Haghdoost.

   - Conversion of __get_cpu_var() from Christoph Lameter.

   - Fix for sector_div() with 64-bit divider from Geert Uytterhoeven.

   - A fix for a race between request completion and the timeout
     handling from Jeff Moyer.  This is what caused the merge conflict
     with blk-mq/core, in case you are looking at that.

   - A dm stacking fix from Mike Snitzer.

   - A code consolidation fix and duplicated code removal from Kent
     Overstreet.

   - A handful of block bug fixes from Mikulas Patocka, fixing a loop
     crash and memory corruption on blk cg.

   - Elevator switch bug fix from Tomoki Sekiyama.

  A heads-up that I had to rebase this branch.  Initially the immutable
  bio_vecs had been queued up for inclusion, but a week later, it became
  clear that it wasn't fully cooked yet.  So the decision was made to
  pull this out and postpone it until 3.14.  It was a straight forward
  rebase, just pruning out the immutable series and the later fixes of
  problems with it.  The rest of the patches applied directly and no
  further changes were made"

* 'for-3.13/core' of git://git.kernel.dk/linux-block: (31 commits)
  block: replace IS_ERR and PTR_ERR with PTR_ERR_OR_ZERO
  block: replace IS_ERR and PTR_ERR with PTR_ERR_OR_ZERO
  block: Do not call sector_div() with a 64-bit divisor
  kernel: trace: blktrace: remove redundent memcpy() in compat_blk_trace_setup()
  block: Consolidate duplicated bio_trim() implementations
  block: Use rw_copy_check_uvector()
  block: Enable sysfs nomerge control for I/O requests in the plug list
  block: properly stack underlying max_segment_size to DM device
  elevator: acquire q->sysfs_lock in elevator_change()
  elevator: Fix a race in elevator switching and md device initialization
  block: Replace __get_cpu_var uses
  bdi: test bdi_init failure
  block: fix a probe argument to blk_register_region
  loop: fix crash if blk_alloc_queue fails
  blk-core: Fix memory corruption if blkcg_init_queue fails
  block: fix race between request completion and timeout handling
  blktrace: Send BLK_TN_PROCESS events to all running traces
  blk-mq: don't disallow request merges for req->special being set
  blk-mq: mq plug list breakage
  blk-mq: fix for flush deadlock
  ...

block: properly stack underlying max_segment_size to DM device

2013-11-08T16:00:17+00:00

Without this patch all DM devices will default to BLK_MAX_SEGMENT_SIZE
(65536) even if the underlying device(s) have a larger value -- this is
due to blk_stack_limits() using min_not_zero() when stacking the
max_segment_size limit.

1073741824

before patch:
65536

after patch:
1073741824

Reported-by: Lukasz Flis 
Signed-off-by: Mike Snitzer 
Cc: stable@vger.kernel.org # v3.3+
Signed-off-by: Jens Axboe

ARM: 7794/1: block: Rename parameter dma_mask to max_addr for blk_queue_bounce_limit()

2013-10-31T14:49:22+00:00

The blk_queue_bounce_limit() API parameter 'dma_mask' is actually the
maximum address the device can handle rather than a dma_mask. Rename
it accordingly to avoid it being interpreted as dma_mask.

No functional change.

The idea is to fix the bad assumptions about dma_mask wherever it could
be miss-interpreted.

Cc: Jens Axboe 
Signed-off-by: Santosh Shilimkar 
Signed-off-by: Russell King

block: discard granularity might not be power of 2

2012-12-14T19:46:04+00:00

In MD raid case, discard granularity might not be power of 2, for example, a
4-disk raid5 has 3*chunk_size discard granularity. Correct the calculation for
such cases.

Reported-by: Neil Brown 
Signed-off-by: Shaohua Li 
Signed-off-by: Jens Axboe

block: Implement support for WRITE SAME

2012-09-20T12:31:45+00:00

The WRITE SAME command supported on some SCSI devices allows the same
block to be efficiently replicated throughout a block range. Only a
single logical block is transferred from the host and the storage device
writes the same data to all blocks described by the I/O.

This patch implements support for WRITE SAME in the block layer. The
blkdev_issue_write_same() function can be used by filesystems and block
drivers to replicate a buffer across a block range. This can be used to
efficiently initialize software RAID devices, etc.

Signed-off-by: Martin K. Petersen 
Acked-by: Mike Snitzer 
Signed-off-by: Jens Axboe

block: do not artificially constrain max_sectors for stacking drivers

2012-08-01T08:44:28+00:00

blk_set_stacking_limits is intended to allow stacking drivers to build
up the limits of the stacked device based on the underlying devices'
limits.  But defaulting 'max_sectors' to BLK_DEF_MAX_SECTORS (1024)
doesn't allow the stacking driver to inherit a max_sectors larger than
1024 -- due to blk_stack_limits' use of min_not_zero.

It is now clear that this artificial limit is getting in the way so
change blk_set_stacking_limits's max_sectors to UINT_MAX (which allows
stacking drivers like dm-multipath to inherit 'max_sectors' from the
underlying paths).

Reported-by: Vijay Chauhan 
Tested-by: Vijay Chauhan 
Signed-off-by: Mike Snitzer 
Signed-off-by: Jens Axboe