android_kernel_google_msm/block
Subhash Jadavani f32dfe2ee0 block: blk-merge: don't merge the pages with non-contiguous descriptors
blk_rq_map_sg() function merges the physically contiguous pages to use same
scatter-gather node without checking if their page descriptors are
contiguous or not.

Now when dma_map_sg() is called on the scatter gather list, it would
take the base page pointer from each node (one by one) and iterates
through all of the pages in same sg node by keep incrementing the base
page pointer with the assumption that physically contiguous pages will
have their page descriptor address contiguous which may not be true
if SPARSEMEM config is enabled. So here we may end referring to invalid
page descriptor.

Following table shows the example of physically contiguous pages but
their page descriptor addresses non-contiguous.
-------------------------------------------
| Page Descriptor    |   Physical Address |
------------------------------------------
| 0xc1e43fdc         |   0xdffff000       |
| 0xc2052000         |   0xe0000000       |
-------------------------------------------

With this patch, relevant blk-merge functions will also check if the
physically contiguous pages are having page descriptors address contiguous
or not? If not then, these pages are separated to be in different
scatter-gather nodes.

(cherry picked from commit 6e25ce37a4f5750467f7c741b549687ebbc10667)

CRs-Fixed: 392141
Change-Id: I3601565e5569a69f06fb3af99061c4d4c23af241
Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org>
2013-03-07 15:25:32 -08:00
..
partitions LDM: Fix reassembly of extended VBLKs. 2012-02-24 09:37:42 +00:00
blk-cgroup.c Merge branch 'for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup 2012-03-20 18:11:21 -07:00
blk-cgroup.h block: fix a typo in the blk-cgroup.h file 2011-10-24 16:08:38 +02:00
blk-core.c block: Add test-iosched scheduler 2013-02-27 18:13:18 -08:00
blk-exec.c block: add missing blk_queue_dead() checks 2011-12-14 00:33:37 +01:00
blk-flush.c blk-flush: move the queue kick into 2011-10-24 16:24:31 +02:00
blk-integrity.c block: add export.h to files using EXPORT_SYMBOL/THIS_MODULE macros 2011-10-31 19:31:12 -04:00
blk-ioc.c block: fix ioc leak in put_io_context 2012-03-14 15:34:48 +01:00
blk-iopoll.c
blk-lib.c block: ioctl support for sanitize in eMMC 4.5 2013-02-20 01:32:26 -08:00
blk-map.c block: re-use existing 'reading' variable instead of checking direction again 2011-12-21 15:27:24 +01:00
blk-merge.c block: blk-merge: don't merge the pages with non-contiguous descriptors 2013-03-07 15:25:32 -08:00
blk-settings.c block: Introduce blk_set_stacking_limits function 2012-01-11 16:27:11 +01:00
blk-softirq.c sched, block: Unify cache detection 2012-01-27 13:28:48 +01:00
blk-sysfs.c block, cfq: move io_cq exit/release to blk-ioc.c 2011-12-14 00:33:42 +01:00
blk-tag.c block: fix blk_queue_end_tag() 2011-12-29 09:16:28 +01:00
blk-throttle.c block: use lockdep_assert_held for queue locking 2012-03-30 12:33:28 +02:00
blk-timeout.c
blk.h Merge branch 'linus' into sched/core 2012-03-01 10:26:43 +01:00
bsg-lib.c block: Change module.h -> export.h in bsg-lib.c 2011-10-31 19:31:13 -04:00
bsg.c bsg: fix sysfs link remove warning 2012-02-08 20:02:03 +01:00
cfq-iosched.c block: Make cfq_target_latency tunable through sysfs. 2012-04-01 14:33:39 -07:00
cfq.h
compat_ioctl.c block: Add BLKROTATIONAL ioctl 2012-01-11 16:29:31 +01:00
deadline-iosched.c block, cfq: move icq cache management to block core 2011-12-14 00:33:42 +01:00
elevator.c block: ioctl support for sanitize in eMMC 4.5 2013-02-20 01:32:26 -08:00
genhd.c block: genhd: Add disk/partition specific uevent callbacks for partition info 2013-02-20 02:50:08 -08:00
ioctl.c block: ioctl support for sanitize in eMMC 4.5 2013-02-20 01:32:26 -08:00
Kconfig move fs/partitions to block/ 2012-01-03 22:54:06 -05:00
Kconfig.iosched block: Add test-iosched scheduler 2013-02-27 18:13:18 -08:00
Makefile block: Add test-iosched scheduler 2013-02-27 18:13:18 -08:00
noop-iosched.c block, cfq: move icq cache management to block core 2011-12-14 00:33:42 +01:00
partition-generic.c block: genhd: Add disk/partition specific uevent callbacks for partition info 2013-02-20 02:50:08 -08:00
scsi_ioctl.c block: fail SCSI passthrough ioctls on partition devices 2012-01-14 15:07:24 -08:00
test-iosched.c mmc: card: Add Sanitize unit test 2013-02-27 18:16:43 -08:00