kernel/linux.git/drivers/md/dm-writecache.c, branch v4.19.112

dm writecache: verify watermark during resume

2020-03-11T13:15:06+00:00

commit 41c526c5af46d4c4dab7f72c99000b7fac0b9702 upstream. Verify the watermark upon resume - so that if the target is reloaded with lower watermark, it will start the cleanup process immediately. Fixes: 48debafe4f2f ("dm: add writecache target") Cc: stable@vger.kernel.org # 4.18+ Signed-off-by: Mikulas Patocka Signed-off-by: Mike Snitzer Signed-off-by: Greg Kroah-Hartman

dm: report suspended device during destroy

2020-03-11T13:15:05+00:00

commit adc0daad366b62ca1bce3e2958a40b0b71a8b8b3 upstream. The function dm_suspended returns true if the target is suspended. However, when the target is being suspended during unload, it returns false. An example where this is a problem: the test "!dm_suspended(wc->ti)" in writecache_writeback is not sufficient, because dm_suspended returns zero while writecache_suspend is in progress. As is, without an enhanced dm_suspended, simply switching from flush_workqueue to drain_workqueue still emits warnings: workqueue writecache-writeback: drain_workqueue() isn't complete after 10 tries workqueue writecache-writeback: drain_workqueue() isn't complete after 100 tries workqueue writecache-writeback: drain_workqueue() isn't complete after 200 tries workqueue writecache-writeback: drain_workqueue() isn't complete after 300 tries workqueue writecache-writeback: drain_workqueue() isn't complete after 400 tries writecache_suspend calls flush_workqueue(wc->writeback_wq) - this function flushes the current work. However, the workqueue may re-queue itself and flush_workqueue doesn't wait for re-queued works to finish. Because of this - the function writecache_writeback continues execution after the device was suspended and then concurrently with writecache_dtr, causing a crash in writecache_writeback. We must use drain_workqueue - that waits until the work and all re-queued works finish. As a prereq for switching to drain_workqueue, this commit fixes dm_suspended to return true after the presuspend hook and before the postsuspend hook - just like during a normal suspend. It allows simplifying the dm-integrity and dm-writecache targets so that they don't have to maintain suspended flags on their own. With this change use of drain_workqueue() can be used effectively. This change was tested with the lvm2 testsuite and cryptsetup testsuite and the are no regressions. Fixes: 48debafe4f2f ("dm: add writecache target") Cc: stable@vger.kernel.org # 4.18+ Reported-by: Corey Marthaler Signed-off-by: Mikulas Patocka Signed-off-by: Mike Snitzer Signed-off-by: Greg Kroah-Hartman

dm writecache: fix incorrect flush sequence when doing SSD mode commit

2020-02-11T12:34:04+00:00

commit aa9509209c5ac2f0b35d01a922bf9ae072d0c2fc upstream. When committing state, the function writecache_flush does the following: 1. write metadata (writecache_commit_flushed) 2. flush disk cache (writecache_commit_flushed) 3. wait for data writes to complete (writecache_wait_for_ios) 4. increase superblock seq_count 5. write the superblock 6. flush disk cache It may happen that at step 3, when we wait for some write to finish, the disk may report the write as finished, but the write only hit the disk cache and it is not yet stored in persistent storage. At step 5 we write the superblock - it may happen that the superblock is written before the write that we waited for in step 3. If the machine crashes, it may result in incorrect data being returned after reboot. In order to fix the bug, we must swap steps 2 and 3 in the above sequence, so that we first wait for writes to complete and then flush the disk cache. Fixes: 48debafe4f2f ("dm: add writecache target") Cc: stable@vger.kernel.org # 4.18+ Signed-off-by: Mikulas Patocka Signed-off-by: Mike Snitzer Signed-off-by: Greg Kroah-Hartman

dm writecache: handle REQ_FUA

2019-12-17T19:34:52+00:00

commit c1005322ff02110a4df7f0033368ea015062b583 upstream. Call writecache_flush() on REQ_FUA in writecache_map(). Cc: stable@vger.kernel.org # 4.18+ Signed-off-by: Maged Mokhtar Acked-by: Mikulas Patocka Signed-off-by: Mike Snitzer Signed-off-by: Greg Kroah-Hartman

Merge tag 'libnvdimm-for-4.19_misc' of gitolite.kernel.org:pub/scm/linux/kernel/git/nvdimm/nvdimm

2018-08-26T01:13:10+00:00

Pull libnvdimm updates from Dave Jiang: "Collection of misc libnvdimm patches for 4.19 submission: - Adding support to read locked nvdimm capacity. - Change test code to make DSM failure code injection an override. - Add support for calculate maximum contiguous area for namespace. - Add support for queueing a short ARS when there is on going ARS for nvdimm. - Allow NULL to be passed in to ->direct_access() for kaddr and pfn params. - Improve smart injection support for nvdimm emulation testing. - Fix test code that supports for emulating controller temperature. - Fix hang on error before devm_memremap_pages() - Fix a bug that causes user memory corruption when data returned to user for ars_status. - Maintainer updates for Ross Zwisler emails and adding Jan Kara to fsdax" * tag 'libnvdimm-for-4.19_misc' of gitolite.kernel.org:pub/scm/linux/kernel/git/nvdimm/nvdimm: libnvdimm: fix ars_status output length calculation device-dax: avoid hang on error before devm_memremap_pages() tools/testing/nvdimm: improve emulation of smart injection filesystem-dax: Do not request kaddr and pfn when not required md/dm-writecache: Don't request pointer dummy_addr when not required dax/super: Do not request a pointer kaddr when not required tools/testing/nvdimm: kaddr and pfn can be NULL to ->direct_access() s390, dcssblk: kaddr and pfn can be NULL to ->direct_access() libnvdimm, pmem: kaddr and pfn can be NULL to ->direct_access() acpi/nfit: queue issuing of ars when an uc error notification comes in libnvdimm: Export max available extent libnvdimm: Use max contiguous area for namespace size MAINTAINERS: Add Jan Kara for filesystem DAX MAINTAINERS: update Ross Zwisler's email address tools/testing/nvdimm: Fix support for emulating controller temperature tools/testing/nvdimm: Make DSM failure code injection an override acpi, nfit: Prefer _DSM over _LSR for namespace label reads libnvdimm: Introduce locked DIMM capacity support

dm writecache: fix a crash due to reading past end of dirty_bitmap

2018-08-16T17:43:01+00:00

wc->dirty_bitmap_size is in bytes so must multiply it by 8, not by BITS_PER_LONG, to get number of bitmap_bits. Fixes crash in find_next_bit() that was reported: https://bugzilla.kernel.org/show_bug.cgi?id=200819 Reported-by: edo.rus@gmail.com Fixes: 48debafe4f2f ("dm: add writecache target") Cc: stable@vger.kernel.org # 4.18 Signed-off-by: Mikulas Patocka Signed-off-by: Mike Snitzer

md/dm-writecache: Don't request pointer dummy_addr when not required

2018-07-30T16:40:04+00:00

Function persistent_memory_claim doesn't need to get local pointer dummy_addr from direct_access. Using NULL instead of having to pass in a useless local pointer that caller then just throw away. Suggested-by: Ross Zwisler Signed-off-by: Huaisheng Ye Reviewed-by: Ross Zwisler Acked-by: Mike Snitzer Signed-off-by: Dave Jiang

dm writecache: report start_sector in status line

2018-07-27T19:28:58+00:00

Fixes: d284f8248c7 ("dm writecache: support optional offset for start of device") Signed-off-by: Mikulas Patocka Signed-off-by: Mike Snitzer

dm writecache: support optional offset for start of device

2018-07-02T20:14:02+00:00

Add an optional parameter "start_sector" to allow the start of the device to be offset by the specified number of 512-byte sectors. The sectors below this offset are not used by the writecache device and are left to be used for disk labels and/or userspace metadata (e.g. lvm). Signed-off-by: Mikulas Patocka Signed-off-by: Mike Snitzer

dm writecache: use 2-factor allocator arguments

2018-06-22T18:51:12+00:00

This adjusts the allocator calls to use the 2-factor argument style, as already done treewide for better defense against allocator overflows. Signed-off-by: Kees Cook [snitzer: tweaked code to leave assignment in a test alone] Signed-off-by: Mike Snitzer