Tejun Heo 7a4dd281ec blkcg: kill the mind-bending blkg->dev ...

blkg->dev is dev_t recording the device number of the block device for
the associated request_queue.  It is used to identify the associated
block device when printing out configuration or stats.

This is redundant to begin with.  A blkg is an association between a
cgroup and a request_queue and it of course is possible to reach
request_queue from blkg and synchronization conventions are in place
for safe q dereferencing, so this shouldn't be necessary from the
beginning.  Furthermore, it's initialized by sscanf()ing the device
name of backing_dev_info.  The mind boggles.

Anyways, if blkg is visible under rcu lock, we *know* that the
associated request_queue hasn't gone away yet and its bdi is
registered and alive - blkg can't be created for request_queue which
hasn't been fully initialized and it can't go away before blkg is
removed.

Let stat and conf read functions get device name from
blkg->q->backing_dev_info.dev and pass it down to printing functions
and remove blkg->dev.

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

2012-03-06 21:27:22 +01:00

..

partitions

separate partition format handling from generic code

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

blk-cgroup.c

blkcg: kill the mind-bending blkg->dev

2012-03-06 21:27:22 +01:00

blk-cgroup.h

blkcg: kill the mind-bending blkg->dev

2012-03-06 21:27:22 +01:00

blk-core.c

blkcg: use the usual get blkg path for root blkio_group

2012-03-06 21:27:22 +01:00

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: exit_io_context() should call elevator_exit_icq_fn()

2012-02-15 09:45:53 +01:00

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

block: Don't check QUEUE_FLAG_SAME_COMP in __blk_complete_request

2011-09-14 09:31:01 +02:00

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

blkcg: kill the mind-bending blkg->dev

2012-03-06 21:27:22 +01:00

blk-timeout.c

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

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

blk.h

block: implement blk_queue_bypass_start/end()

2012-03-06 21:27:21 +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

blkcg: kill the mind-bending blkg->dev

2012-03-06 21:27:22 +01:00

cfq.h

blkcg: factor out blkio_group creation

2012-03-06 21:27:22 +01:00

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

blkcg: shoot down blkio_groups on elevator switch

2012-03-06 21:27:22 +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