Tejun Heo 80fd99792b blkcg: make sure blkg_lookup() returns %NULL if @q is bypassing ...

Currently, blkg_lookup() doesn't check @q bypass state.  This patch
updates blk_queue_bypass_start() to do synchronize_rcu() before
returning and updates blkg_lookup() to check blk_queue_bypass() and
return %NULL if bypassing.  This ensures blkg_lookup() returns %NULL
if @q is bypassing.

This is to guarantee that nobody is accessing policy data while @q is
bypassing, which is necessary to allow replacing blkio_cgroup->pd[] in
place on policy [de]activation.

v2: Added more comments explaining bypass guarantees as suggested by
    Vivek.

v3: Added more comments explaining why there's no synchronize_rcu() in
    blk_cleanup_queue() as suggested by Vivek.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

2012-04-20 10:06:06 +02:00

..

partitions

LDM: Fix reassembly of extended VBLKs.

2012-02-24 09:37:42 +00:00

blk-cgroup.c

blkcg: make sure blkg_lookup() returns %NULL if @q is bypassing

2012-04-20 10:06:06 +02:00

blk-cgroup.h

blkcg: make blkg_conf_prep() take @pol and return with queue lock held

2012-04-20 10:06:06 +02:00

blk-core.c

blkcg: make sure blkg_lookup() returns %NULL if @q is bypassing

2012-04-20 10:06:06 +02:00

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

Merge branch 'for-3.5' of ../cgroup into block/for-3.5/core-merged

2012-04-01 12:55:00 -07:00

blk-iopoll.c

tree-wide: fix assorted typos all over the place

2009-12-04 15:39:55 +01:00

blk-lib.c

block: fix patch import error in max_discard_sectors check

2011-07-23 20:34:59 +02:00

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: separate out blk_rq_merge_ok() and blk_try_merge() from elevator functions

2012-02-08 09:19:38 +01:00

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

blkcg: unify blkg's for blkcg policies

2012-03-06 21:27:23 +01:00

blk-tag.c

block: fix blk_queue_end_tag()

2011-12-29 09:16:28 +01:00

blk-throttle.c

blkcg: make blkg_conf_prep() take @pol and return with queue lock held

2012-04-20 10:06:06 +02:00

blk-timeout.c

fault-injection: add ability to export fault_attr in arbitrary directory

2011-08-03 14:25:20 -10:00

blk.h

Merge branch 'for-3.5' of ../cgroup into block/for-3.5/core-merged

2012-04-01 12:55:00 -07:00

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

blkcg: make blkg_conf_prep() take @pol and return with queue lock held

2012-04-20 10:06:06 +02:00

compat_ioctl.c

block: Add BLKROTATIONAL ioctl

2012-01-11 16:29:31 +01:00

deadline-iosched.c

elevator: make elevator_init_fn() return 0/-errno

2012-03-06 21:27:21 +01:00

elevator.c

block: implement bio_associate_current()

2012-03-06 21:27:24 +01:00

genhd.c

Block: use a freezable workqueue for disk-event polling

2012-03-02 10:51:00 +01:00

ioctl.c

Merge branch 'for-3.3/core' of git://git.kernel.dk/linux-block

2012-01-15 12:24:45 -08:00

Kconfig

move fs/partitions to block/

2012-01-03 22:54:06 -05:00

Kconfig.iosched

blkcg: make CONFIG_BLK_CGROUP bool

2012-03-06 21:27:21 +01:00

Makefile

separate partition format handling from generic code

2012-01-03 22:54:06 -05:00

noop-iosched.c

elevator: make elevator_init_fn() return 0/-errno

2012-03-06 21:27:21 +01:00

partition-generic.c

block: Fix NULL pointer dereference in sd_revalidate_disk

2012-03-02 10:38:33 +01:00

scsi_ioctl.c

block: fail SCSI passthrough ioctls on partition devices

2012-01-14 15:07:24 -08:00