user/sven/linux.git/drivers/md, branch v4.0

Merge tag 'dm-4.0-fix-2' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

2015-03-26T21:53:47Z

Pull device mapper fix from Mike Snitzer: "Fix DM core device cleanup regression -- due to a latent race that was exposed by the bdi changes that were introduced during the 4.0 merge" * tag 'dm-4.0-fix-2' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: dm: fix add_disk() NULL pointer due to race with free_dev()

dm: fix add_disk() NULL pointer due to race with free_dev()

2015-03-23T22:14:00Z

Commit c4db59d31e39 ("fs: don't reassign dirty inodes to default_backing_dev_info") exposed DM to a latent race in free_dev() vs add_disk() in relation to management of the device's minor number. Fix this by refactoring free_dev() to match cleanup order of the alloc_dev() error path. Move cleanup of the gendisk, queue, and bdev to _before_ the cleanup of the idr managed minor number. Also, purely due to cleanup that fell out during the free_dev() audit: - adjust dm_blk_close() to access the gendisk's private_data under the _minor_lock spinlock. - move __dm_destroy()'s dm_get_live_table() call out from under the _minor_lock spinlock. Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1202449 Reported-by: Zdenek Kabelac Reported-by: Jeff Moyer Signed-off-by: Mike Snitzer

Merge tag 'md/4.0-rc4-fix' of git://neil.brown.name/md

2015-03-22T23:38:19Z

Pull bugfix for md from Neil Brown: "One fix for md in 4.0-rc4 Regression in recent patch causes crash on error path" * tag 'md/4.0-rc4-fix' of git://neil.brown.name/md: md: fix problems with freeing private data after ->run failure.

Merge tag 'dm-4.0-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

2015-03-21T18:15:13Z

Pull devicemapper fixes from Mike Snitzer: "A handful of stable fixes for DM: - fix thin target to always zero-fill reads to unprovisioned blocks - fix to interlock device destruction's suspend from internal suspends - fix 2 snapshot exception store handover bugs - fix dm-io to cope with DISCARD and WRITE_SAME capabilities changing" * tag 'dm-4.0-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: dm io: deal with wandering queue limits when handling REQ_DISCARD and REQ_WRITE_SAME dm snapshot: suspend merging snapshot when doing exception handover dm snapshot: suspend origin when doing exception handover dm: hold suspend_lock while suspending device during device deletion dm thin: fix to consistently zero-fill reads to unprovisioned blocks

md: fix problems with freeing private data after ->run failure.

2015-03-20T22:40:36Z

If ->run() fails, it can either free the data structures it allocated, or leave that task to ->free() which will be called on failures. However: md.c calls ->free() even if ->private_data is NULL, which causes problems in some personalities. raid0.c frees the data, but doesn't clear ->private_data, which will become a problem when we fix md.c So better fix both these issues at once. Reported-by: Richard W.M. Jones Fixes: 5aa61f427e4979be733e4847b9199ff9cc48a47e URL: https://bugzilla.kernel.org/show_bug.cgi?id=94381 Signed-off-by: NeilBrown

dm io: deal with wandering queue limits when handling REQ_DISCARD and REQ_WRITE_SAME

2015-02-27T19:53:32Z

Since it's possible for the discard and write same queue limits to change while the upper level command is being sliced and diced, fix up both of them (a) to reject IO if the special command is unsupported at the start of the function and (b) read the limits once and let the commands error out on their own if the status happens to change. Signed-off-by: Darrick J. Wong Signed-off-by: Mikulas Patocka Signed-off-by: Mike Snitzer Cc: stable@vger.kernel.org

dm snapshot: suspend merging snapshot when doing exception handover

2015-02-27T19:53:16Z

The "dm snapshot: suspend origin when doing exception handover" commit fixed a exception store handover bug associated with pending exceptions to the "snapshot-origin" target. However, a similar problem exists in snapshot merging. When snapshot merging is in progress, we use the target "snapshot-merge" instead of "snapshot-origin". Consequently, during exception store handover, we must find the snapshot-merge target and suspend its associated mapped_device. To avoid lockdep warnings, the target must be suspended and resumed without holding _origins_lock. Introduce a dm_hold() function that grabs a reference on a mapped_device, but unlike dm_get(), it doesn't crash if the device has the DMF_FREEING flag set, it returns an error in this case. In snapshot_resume() we grab the reference to the origin device using dm_hold() while holding _origins_lock (_origins_lock guarantees that the device won't disappear). Then we release _origins_lock, suspend the device and grab _origins_lock again. NOTE to stable@ people: When backporting to kernels 3.18 and older, use dm_internal_suspend and dm_internal_resume instead of dm_internal_suspend_fast and dm_internal_resume_fast. Signed-off-by: Mikulas Patocka Signed-off-by: Mike Snitzer Cc: stable@vger.kernel.org

dm snapshot: suspend origin when doing exception handover

2015-02-27T19:49:47Z

In the function snapshot_resume we perform exception store handover. If there is another active snapshot target, the exception store is moved from this target to the target that is being resumed. The problem is that if there is some pending exception, it will point to an incorrect exception store after that handover, causing a crash due to dm-snap-persistent.c:get_exception()'s BUG_ON. This bug can be triggered by repeatedly changing snapshot permissions with "lvchange -p r" and "lvchange -p rw" while there are writes on the associated origin device. To fix this bug, we must suspend the origin device when doing the exception store handover to make sure that there are no pending exceptions: - introduce _origin_hash that keeps track of dm_origin structures. - introduce functions __lookup_dm_origin, __insert_dm_origin and __remove_dm_origin that manipulate the origin hash. - modify snapshot_resume so that it calls dm_internal_suspend_fast() and dm_internal_resume_fast() on the origin device. NOTE to stable@ people: When backporting to kernels 3.12-3.18, use dm_internal_suspend and dm_internal_resume instead of dm_internal_suspend_fast and dm_internal_resume_fast. When backporting to kernels older than 3.12, you need to pick functions dm_internal_suspend and dm_internal_resume from the commit fd2ed4d252701d3bbed4cd3e3d267ad469bb832a. Signed-off-by: Mikulas Patocka Signed-off-by: Mike Snitzer Cc: stable@vger.kernel.org

dm: hold suspend_lock while suspending device during device deletion

2015-02-27T19:09:23Z

__dm_destroy() must take the suspend_lock so that its presuspend and postsuspend calls do not race with an internal suspend. Signed-off-by: Mikulas Patocka Signed-off-by: Mike Snitzer Cc: stable@vger.kernel.org

dm thin: fix to consistently zero-fill reads to unprovisioned blocks

2015-02-27T14:59:12Z

It was always intended that a read to an unprovisioned block will return zeroes regardless of whether the pool is in read-only or read-write mode. thin_bio_map() was inconsistent with its handling of such reads when the pool is in read-only mode, it now properly zero-fills the bios it returns in response to unprovisioned block reads. Eliminate thin_bio_map()'s special read-only mode handling of -ENODATA and just allow the IO to be deferred to the worker which will result in pool->process_bio() handling the IO (which already properly zero-fills reads to unprovisioned blocks). Reported-by: Eric Sandeen Signed-off-by: Joe Thornber Signed-off-by: Mike Snitzer Cc: stable@vger.kernel.org