linux/drivers/block/aoe
Tejun Heo e71bf0d0ee block: fix disk->part[] dereferencing race
disk->part[] is protected by its matching bdev's lock.  However,
non-critical accesses like collecting stats and printing out sysfs and
proc information used to be performed without any locking.  As
partitions can come and go dynamically, partitions can go away
underneath those non-critical accesses.  As some of those accesses are
writes, this theoretically can lead to silent corruption.

This patch fixes the race by using RCU for the partition array and dev
reference counter to hold partitions.

* Rename disk->part[] to disk->__part[] to make sure no one outside
  genhd layer proper accesses it directly.

* Use RCU for disk->__part[] dereferencing.

* Implement disk_{get|put}_part() which can be used to get and put
  partitions from gendisk respectively.

* Iterators are implemented to help iterate through all partitions
  safely.

* Functions which require RCU readlock are marked with _rcu suffix.

* Use disk_put_part() in __blkdev_put() instead of directly putting
  the contained kobject.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:06 +02:00
..
aoe.h remove aoedev_isbusy() 2008-04-29 08:06:24 -07:00
aoeblk.c aoe: update copyright date 2008-02-08 09:22:32 -08:00
aoechr.c aoe: convert emsgs_sema into a completion 2008-07-25 10:53:45 -07:00
aoecmd.c block: fix disk->part[] dereferencing race 2008-10-09 08:56:06 +02:00
aoedev.c remove aoedev_isbusy() 2008-04-29 08:06:24 -07:00
aoemain.c aoe: update copyright date 2008-02-08 09:22:32 -08:00
aoenet.c Remove newline from the description of module parameters 2008-08-01 12:46:41 -07:00
Makefile Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00