Tejun Heo ab0fd1debe block: don't merge requests of different failfast settings ... Block layer used to merge requests and bios with different failfast settings. This caused regular IOs to fail prematurely when they were merged into failfast requests for readahead. Niel Lambrechts could trigger the problem semi-reliably on ext4 when resuming from STR. ext4 uses readahead when reading inodes and combined with the deterministic extra SATA PHY exception cycle during resume on the specific configuration, non-readahead inode read would fail causing ext4 errors. Please read the following thread for details. http://lkml.org/lkml/2009/5/23/21 This patch makes block layer reject merging if the failfast settings don't match. This is correct but likely to lower IO performance by preventing regular IOs from mingling into surrounding readahead requests. Changes to allow such mixed merges and handle errors correctly will be added later. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Niel Lambrechts <niel.lambrechts@gmail.com> Cc: Theodore Tso <tytso@mit.edu> Signed-off-by: Jens Axboe <axboe@carl.(none)>		2009-07-03 21:06:45 +02:00
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as-iosched.c
blk-barrier.c
blk-core.c	blocK: Restore barrier support for md and probably other virtual devices.	2009-07-01 10:56:26 +02:00
blk-exec.c
blk-integrity.c
blk-ioc.c
blk-map.c
blk-merge.c	block: don't merge requests of different failfast settings	2009-07-03 21:06:45 +02:00
blk-settings.c
blk-softirq.c
blk-sysfs.c
blk-tag.c
blk-timeout.c
blk.h
bsg.c	block: get rid of queue-private command filter	2009-07-01 10:56:26 +02:00
cfq-iosched.c	cfq-iosched: remove redundant check for NULL cfqq in cfq_set_request()	2009-07-01 12:41:14 +02:00
compat_ioctl.c
deadline-iosched.c
elevator.c	block: don't merge requests of different failfast settings	2009-07-03 21:06:45 +02:00
genhd.c
ioctl.c
Kconfig
Kconfig.iosched
Makefile	block: get rid of queue-private command filter	2009-07-01 10:56:26 +02:00
noop-iosched.c
scsi_ioctl.c	block: get rid of queue-private command filter	2009-07-01 10:56:26 +02:00