kernel/linux.git/drivers/block/rbd.c, branch v3.18.62

rbd: use GFP_NOIO consistently for request allocations

2016-04-20T13:40:51+00:00

[ Upstream commit 2224d879c7c0f85c14183ef82eb48bd875ceb599 ] As of 5a60e87603c4c533492c515b7f62578189b03c9c, RBD object request allocations are made via rbd_obj_request_create() with GFP_NOIO. However, subsequent OSD request allocations in rbd_osd_req_create*() use GFP_ATOMIC. With heavy page cache usage (e.g. OSDs running on same host as krbd client), rbd_osd_req_create() order-1 GFP_ATOMIC allocations have been observed to fail, where direct reclaim would have allowed GFP_NOIO allocations to succeed. Cc: stable@vger.kernel.org # 3.18+ Suggested-by: Vlastimil Babka Suggested-by: Neil Brown Signed-off-by: David Disseldorp Signed-off-by: Ilya Dryomov Signed-off-by: Sasha Levin

rbd: don't leak parent_spec in rbd_dev_probe_parent()

2016-01-22T17:24:43+00:00

[ Upstream commit 1f2c6651f69c14d0d3a9cfbda44ea101b02160ba ] Currently we leak parent_spec and trigger a "parent reference underflow" warning if rbd_dev_create() in rbd_dev_probe_parent() fails. The problem is we take the !parent out_err branch and that only drops refcounts; parent_spec that would've been freed had we called rbd_dev_unparent() remains and triggers rbd_warn() in rbd_dev_parent_put() - at that point we have parent_spec != NULL and parent_ref == 0, so counter ends up being -1 after the decrement. Redo rbd_dev_probe_parent() to fix this. Cc: stable@vger.kernel.org # 3.10+, needs backporting for < 4.2 Signed-off-by: Ilya Dryomov Reviewed-by: Alex Elder Signed-off-by: Sasha Levin

rbd: don't put snap_context twice in rbd_queue_workfn()

2016-01-21T16:23:28+00:00

[ Upstream commit 70b16db86f564977df074072143284aec2cb1162 ] Commit 4e752f0ab0e8 ("rbd: access snapshot context and mapping size safely") moved ceph_get_snap_context() out of rbd_img_request_create() and into rbd_queue_workfn(), adding a ceph_put_snap_context() to the error path in rbd_queue_workfn(). However, rbd_img_request_create() consumes a ref on snapc, so calling ceph_put_snap_context() after a successful rbd_img_request_create() leads to an extra put. Fix it. Cc: stable@vger.kernel.org # 3.18+ Signed-off-by: Ilya Dryomov Reviewed-by: Josh Durgin Signed-off-by: Sasha Levin

rbd: require stable pages if message data CRCs are enabled

2015-11-15T17:51:50+00:00

[ Upstream commit bae818ee1577c27356093901a0ea48f672eda514 ] rbd requires stable pages, as it performs a crc of the page data before they are send to the OSDs. But since kernel 3.9 (patch 1d1d1a767206fbe5d4c69493b7e6d2a8d08cc0a0 "mm: only enforce stable page writes if the backing device requires it") it is not assumed anymore that block devices require stable pages. This patch sets the necessary flag to get stable pages back for rbd. In a ceph installation that provides multiple ext4 formatted rbd devices "bad crc" messages appeared regularly (ca 1 message every 1-2 minutes on every OSD that provided the data for the rbd) in the OSD-logs before this patch. After this patch this messages are pretty much gone (only ca 1-2 / month / OSD). Cc: stable@vger.kernel.org # 3.9+, needs backporting Signed-off-by: Ronny Hegewald [idryomov@gmail.com: require stable pages only in crc case, changelog] Signed-off-by: Ilya Dryomov Signed-off-by: Sasha Levin

rbd: fix double free on rbd_dev->header_name

2015-11-13T18:19:56+00:00

[ Upstream commit 3ebe138ac642a195c7f2efdb918f464734421fd6 ] If rbd_dev_image_probe() in rbd_dev_probe_parent() fails, header_name is freed twice: once in rbd_dev_probe_parent() and then in its caller rbd_dev_image_probe() (rbd_dev_image_probe() is called recursively to handle parent images). rbd_dev_probe_parent() is responsible for probing the parent, so it shouldn't muck with clone's fields. Signed-off-by: Ilya Dryomov Reviewed-by: Alex Elder Signed-off-by: Sasha Levin

rbd: fix copyup completion race

2015-08-27T17:25:27+00:00

[ Upstream commit 2761713d35e370fd640b5781109f753066b746c4 ] For write/discard obj_requests that involved a copyup method call, the opcode of the first op is CEPH_OSD_OP_CALL and the ->callback is rbd_img_obj_copyup_callback(). The latter frees copyup pages, sets ->xferred and delegates to rbd_img_obj_callback(), the "normal" image object callback, for reporting to block layer and putting refs. rbd_osd_req_callback() however treats CEPH_OSD_OP_CALL as a trivial op, which means obj_request is marked done in rbd_osd_trivial_callback(), *before* ->callback is invoked and rbd_img_obj_copyup_callback() has a chance to run. Marking obj_request done essentially means giving rbd_img_obj_callback() a license to end it at any moment, so if another obj_request from the same img_request is being completed concurrently, rbd_img_obj_end_request() may very well be called on such prematurally marked done request: handle_reply() rbd_osd_req_callback() rbd_osd_trivial_callback() rbd_obj_request_complete() rbd_img_obj_copyup_callback() rbd_img_obj_callback() handle_reply() rbd_osd_req_callback() rbd_osd_trivial_callback() for_each_obj_request(obj_request->img_request) { rbd_img_obj_end_request(obj_request-1/2) rbd_img_obj_end_request(obj_request-2/2) <-- } Calling rbd_img_obj_end_request() on such a request leads to trouble, in particular because its ->xfferred is 0. We report 0 to the block layer with blk_update_request(), get back 1 for "this request has more data in flight" and then trip on rbd_assert(more ^ (which == img_request->obj_request_count)); with rhs (which == ...) being 1 because rbd_img_obj_end_request() has been called for both requests and lhs (more) being 1 because we haven't got a chance to set ->xfferred in rbd_img_obj_copyup_callback() yet. To fix this, leverage that rbd wants to call class methods in only two cases: one is a generic method call wrapper (obj_request is standalone) and the other is a copyup (obj_request is part of an img_request). So make a dedicated handler for CEPH_OSD_OP_CALL and directly invoke rbd_img_obj_copyup_callback() from it if obj_request is part of an img_request, similar to how CEPH_OSD_OP_READ handler invokes rbd_img_obj_request_read_callback(). Since rbd_img_obj_copyup_callback() is now being called from the OSD request callback (only), it is renamed to rbd_osd_copyup_callback(). Cc: Alex Elder Cc: stable@vger.kernel.org # 3.10+, needs backporting for < 3.18 Signed-off-by: Ilya Dryomov Reviewed-by: Alex Elder Signed-off-by: Sasha Levin

rbd: use GFP_NOIO in rbd_obj_request_create()

2015-07-05T14:12:55+00:00

[ Upstream commit 5a60e87603c4c533492c515b7f62578189b03c9c ] rbd_obj_request_create() is called on the main I/O path, so we need to use GFP_NOIO to make sure allocation doesn't blow back on us. Not all callers need this, but I'm still hardcoding the flag inside rather than making it a parameter because a) this is going to stable, and b) those callers shouldn't really use rbd_obj_request_create() and will be fixed in the future. More memory allocation fixes will follow. Cc: stable@vger.kernel.org # 3.10+ Signed-off-by: Ilya Dryomov Reviewed-by: Alex Elder Signed-off-by: Sasha Levin

rbd: end I/O the entire obj_request on error

2015-05-17T23:12:40+00:00

[ Upstream commit 082a75dad84d79d1c15ea9e50f31cb4bb4fa7fd6 ] When we end I/O struct request with error, we need to pass obj_request->length as @nr_bytes so that the entire obj_request worth of bytes is completed. Otherwise block layer ends up confused and we trip on rbd_assert(more ^ (which == img_request->obj_request_count)); in rbd_img_obj_callback() due to more being true no matter what. We already do it in most cases but we are missing some, in particular those where we don't even get a chance to submit any obj_requests, due to an early -ENOMEM for example. A number of obj_request->xferred assignments seem to be redundant but I haven't touched any of obj_request->xferred stuff to keep this small and isolated. Cc: Alex Elder Cc: stable@vger.kernel.org # 3.10+ Reported-by: Shawn Edwards Reviewed-by: Sage Weil Signed-off-by: Ilya Dryomov Signed-off-by: Sasha Levin

rbd: fix rbd_dev_parent_get() when parent_overlap == 0

2015-02-06T06:36:04+00:00

commit ae43e9d05eb4bd324155292f889fbd001c4faea8 upstream. The comment for rbd_dev_parent_get() said * We must get the reference before checking for the overlap to * coordinate properly with zeroing the parent overlap in * rbd_dev_v2_parent_info() when an image gets flattened. We * drop it again if there is no overlap. but the "drop it again if there is no overlap" part was missing from the implementation. This lead to absurd parent_ref values for images with parent_overlap == 0, as parent_ref was incremented for each img_request and virtually never decremented. Fix this by leveraging the fact that refresh path calls rbd_dev_v2_parent_info() under header_rwsem and use it for read in rbd_dev_parent_get(), instead of messing around with atomics. Get rid of barriers in rbd_dev_v2_parent_info() while at it - I don't see what they'd pair with now and I suspect we are in a pretty miserable situation as far as proper locking goes regardless. Signed-off-by: Ilya Dryomov Reviewed-by: Josh Durgin Reviewed-by: Alex Elder Signed-off-by: Greg Kroah-Hartman

rbd: drop parent_ref in rbd_dev_unprobe() unconditionally

2015-02-06T06:36:04+00:00

commit e69b8d414f948c242ad9f3eb2b7e24fba783dbbd upstream. This effectively reverts the last hunk of 392a9dad7e77 ("rbd: detect when clone image is flattened"). The problem with parent_overlap != 0 condition is that it's possible and completely valid to have an image with parent_overlap == 0 whose parent state needs to be cleaned up on unmap. The next commit, which drops the "clone image now standalone" logic, opens up another window of opportunity to hit this, but even without it # cat parent-ref.sh #!/bin/bash rbd create --image-format 2 --size 1 foo rbd snap create foo@snap rbd snap protect foo@snap rbd clone foo@snap bar rbd resize --allow-shrink --size 0 bar rbd resize --size 1 bar DEV=$(rbd map bar) rbd unmap $DEV leaves rbd_device/rbd_spec/etc and rbd_client along with ceph_client hanging around. My thinking behind calling rbd_dev_parent_put() unconditionally is that there shouldn't be any requests in flight at that point in time as we are deep into unmap sequence. Hence, even if rbd_dev_unparent() caused by flatten is delayed by in-flight requests, it will have finished by the time we reach rbd_dev_unprobe() caused by unmap, thus turning unconditional rbd_dev_parent_put() into a no-op. Fixes: http://tracker.ceph.com/issues/10352 Signed-off-by: Ilya Dryomov Reviewed-by: Josh Durgin Reviewed-by: Alex Elder Signed-off-by: Greg Kroah-Hartman