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2021-06-30Merge tag 'for-5.14/dm-changes' of ↵Linus Torvalds32-592/+2411
git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm Pull device mapper updates from Mike Snitzer: - Various DM persistent-data library improvements and fixes that benefit both the DM thinp and cache targets. - A few small DM kcopyd efficiency improvements. - Significant zoned related block core, DM core and DM zoned target changes that culminate with adding zoned append emulation (which is required to properly fix DM crypt's zoned support). - Various DM writecache target changes that improve efficiency. Adds an optional "metadata_only" feature that only promotes bios flagged with REQ_META. But the most significant improvement is writecache's ability to pause writeback, for a confiurable time, if/when the working set is larger than the cache (and the cache is full) -- this ensures performance is no worse than the slower origin device. * tag 'for-5.14/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (35 commits) dm writecache: make writeback pause configurable dm writecache: pause writeback if cache full and origin being written directly dm io tracker: factor out IO tracker dm btree remove: assign new_root only when removal succeeds dm zone: fix dm_revalidate_zones() memory allocation dm ps io affinity: remove redundant continue statement dm writecache: add optional "metadata_only" parameter dm writecache: add "cleaner" and "max_age" to Documentation dm writecache: write at least 4k when committing dm writecache: flush origin device when writing and cache is full dm writecache: have ssd writeback wait if the kcopyd workqueue is busy dm writecache: use list_move instead of list_del/list_add in writecache_writeback() dm writecache: commit just one block, not a full page dm writecache: remove unused gfp_t argument from wc_add_block() dm crypt: Fix zoned block device support dm: introduce zone append emulation dm: rearrange core declarations for extended use from dm-zone.c block: introduce BIO_ZONE_WRITE_LOCKED bio flag block: introduce bio zone helpers block: improve handling of all zones reset operation ...
2021-06-30Merge tag 'for-5.14/drivers-2021-06-29' of git://git.kernel.dk/linux-blockLinus Torvalds13-83/+149
Pull block driver updates from Jens Axboe: "Pretty calm round, mostly just NVMe and a bit of MD: - NVMe updates (via Christoph) - improve the APST configuration algorithm (Alexey Bogoslavsky) - look for StorageD3Enable on companion ACPI device (Mario Limonciello) - allow selecting the network interface for TCP connections (Martin Belanger) - misc cleanups (Amit Engel, Chaitanya Kulkarni, Colin Ian King, Christoph) - move the ACPI StorageD3 code to drivers/acpi/ and add quirks for certain AMD CPUs (Mario Limonciello) - zoned device support for nvmet (Chaitanya Kulkarni) - fix the rules for changing the serial number in nvmet (Noam Gottlieb) - various small fixes and cleanups (Dan Carpenter, JK Kim, Chaitanya Kulkarni, Hannes Reinecke, Wesley Sheng, Geert Uytterhoeven, Daniel Wagner) - MD updates (Via Song) - iostats rewrite (Guoqing Jiang) - raid5 lock contention optimization (Gal Ofri) - Fall through warning fix (Gustavo) - Misc fixes (Gustavo, Jiapeng)" * tag 'for-5.14/drivers-2021-06-29' of git://git.kernel.dk/linux-block: (78 commits) nvmet: use NVMET_MAX_NAMESPACES to set nn value loop: Fix missing discard support when using LOOP_CONFIGURE nvme.h: add missing nvme_lba_range_type endianness annotations nvme: remove zeroout memset call for struct nvme-pci: remove zeroout memset call for struct nvmet: remove zeroout memset call for struct nvmet: add ZBD over ZNS backend support nvmet: add Command Set Identifier support nvmet: add nvmet_req_bio put helper for backends nvmet: add req cns error complete helper block: export blk_next_bio() nvmet: remove local variable nvmet: use nvme status value directly nvmet: use u32 type for the local variable nsid nvmet: use u32 for nvmet_subsys max_nsid nvmet: use req->cmd directly in file-ns fast path nvmet: use req->cmd directly in bdev-ns fast path nvmet: make ver stable once connection established nvmet: allow mn change if subsys not discovered nvmet: make sn stable once connection was established ...
2021-06-30Merge tag 'for-5.14/block-2021-06-29' of git://git.kernel.dk/linux-blockLinus Torvalds5-45/+26
Pull core block updates from Jens Axboe: - disk events cleanup (Christoph) - gendisk and request queue allocation simplifications (Christoph) - bdev_disk_changed cleanups (Christoph) - IO priority improvements (Bart) - Chained bio completion trace fix (Edward) - blk-wbt fixes (Jan) - blk-wbt enable/disable fix (Zhang) - Scheduler dispatch improvements (Jan, Ming) - Shared tagset scheduler improvements (John) - BFQ updates (Paolo, Luca, Pietro) - BFQ lock inversion fix (Jan) - Documentation improvements (Kir) - CLONE_IO block cgroup fix (Tejun) - Remove of ancient and deprecated block dump feature (zhangyi) - Discard merge fix (Ming) - Misc fixes or followup fixes (Colin, Damien, Dan, Long, Max, Thomas, Yang) * tag 'for-5.14/block-2021-06-29' of git://git.kernel.dk/linux-block: (129 commits) block: fix discard request merge block/mq-deadline: Remove a WARN_ON_ONCE() call blk-mq: update hctx->dispatch_busy in case of real scheduler blk: Fix lock inversion between ioc lock and bfqd lock bfq: Remove merged request already in bfq_requests_merged() block: pass a gendisk to bdev_disk_changed block: move bdev_disk_changed block: add the events* attributes to disk_attrs block: move the disk events code to a separate file block: fix trace completion for chained bio block/partitions/msdos: Fix typo inidicator -> indicator block, bfq: reset waker pointer with shared queues block, bfq: check waker only for queues with no in-flight I/O block, bfq: avoid delayed merge of async queues block, bfq: boost throughput by extending queue-merging times block, bfq: consider also creation time in delayed stable merge block, bfq: fix delayed stable merge check block, bfq: let also stably merged queues enjoy weight raising blk-wbt: make sure throttle is enabled properly blk-wbt: introduce a new disable state to prevent false positive by rwb_enabled() ...
2021-06-28dm writecache: make writeback pause configurableMikulas Patocka2-8/+52
Commit 95b88f4d71cb953e02206be3c757083601391a0f ("dm writecache: pause writeback if cache full and origin being written directly") introduced a code that pauses cache flushing if we are issuing writes directly to the origin. Improve that initial commit by making the timeout code configurable (via the option "pause_writeback"). Also change the default from 1s to 3s because it performed better. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-06-25dm writecache: pause writeback if cache full and origin being written directlyMikulas Patocka1-1/+20
Implementation reuses dm_io_tracker, that until now was only used by dm-cache, to track if any writes were issued directly to the origin (due to cache being full) within the last second. If so writeback is paused for a second. This change improves performance for when the cache is full and IO is issued directly to the origin device (rather than through the cache). Depends-on: d53f1fafec9d ("dm writecache: do direct write if the cache is full") Suggested-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-06-25dm io tracker: factor out IO trackerMike Snitzer2-76/+75
Allow other code to use dm_io_tracker. Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-06-25dm btree remove: assign new_root only when removal succeedsHou Tao1-1/+2
remove_raw() in dm_btree_remove() may fail due to IO read error (e.g. read the content of origin block fails during shadowing), and the value of shadow_spine::root is uninitialized, but the uninitialized value is still assign to new_root in the end of dm_btree_remove(). For dm-thin, the value of pmd->details_root or pmd->root will become an uninitialized value, so if trying to read details_info tree again out-of-bound memory may occur as showed below: general protection fault, probably for non-canonical address 0x3fdcb14c8d7520 CPU: 4 PID: 515 Comm: dmsetup Not tainted 5.13.0-rc6 Hardware name: QEMU Standard PC RIP: 0010:metadata_ll_load_ie+0x14/0x30 Call Trace: sm_metadata_count_is_more_than_one+0xb9/0xe0 dm_tm_shadow_block+0x52/0x1c0 shadow_step+0x59/0xf0 remove_raw+0xb2/0x170 dm_btree_remove+0xf4/0x1c0 dm_pool_delete_thin_device+0xc3/0x140 pool_message+0x218/0x2b0 target_message+0x251/0x290 ctl_ioctl+0x1c4/0x4d0 dm_ctl_ioctl+0xe/0x20 __x64_sys_ioctl+0x7b/0xb0 do_syscall_64+0x40/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xae Fixing it by only assign new_root when removal succeeds Signed-off-by: Hou Tao <houtao1@huawei.com> Cc: stable@vger.kernel.org Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-06-25dm zone: fix dm_revalidate_zones() memory allocationDamien Le Moal1-2/+8
Make sure that the zone write pointer offset array is allocated with a vmalloc in dm_zone_revalidate_cb() by passing GFP_KERNEL gfp flag to kvcalloc(). However, since we do not want to trigger IOs while revalidating zones, change dm_revalidate_zones() to have the zone scan done in GFP_NOIO context using memalloc_noio_save/restore calls. Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Fixes: bb37d77239af ("dm: introduce zone append emulation") Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-06-25dm ps io affinity: remove redundant continue statementColin Ian King1-1/+0
The continue statement at the end of a for-loop has no effect, remove it. Addresses-Coverity: ("Continue has no effect") Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-06-25dm writecache: add optional "metadata_only" parameterMikulas Patocka1-4/+12
Add a "metadata_only" parameter that when present: only metadata is promoted to the cache. This option improves performance for heavier REQ_META workloads (e.g. device-mapper-test-suite's "git clone and checkout" benchmark improves from 341s to 312s). Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-06-21dm writecache: write at least 4k when committingMikulas Patocka1-1/+5
SSDs perform badly with sub-4k writes (because they perfrorm read-modify-write internally), so make sure writecache writes at least 4k when committing. Fixes: 991bd8d7bc78 ("dm writecache: commit just one block, not a full page") Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-06-18sched: Change task_struct::statePeter Zijlstra1-3/+3
Change the type and name of task_struct::state. Drop the volatile and shrink it to an 'unsigned int'. Rename it in order to find all uses such that we can use READ_ONCE/WRITE_ONCE as appropriate. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Daniel Bristot de Oliveira <bristot@redhat.com> Acked-by: Will Deacon <will@kernel.org> Acked-by: Daniel Thompson <daniel.thompson@linaro.org> Link: https://lore.kernel.org/r/20210611082838.550736351@infradead.org
2021-06-16dm writecache: flush origin device when writing and cache is fullMikulas Patocka1-2/+6
Commit d53f1fafec9d086f1c5166436abefdaef30e0363 ("dm writecache: do direct write if the cache is full") changed dm-writecache, so that it writes directly to the origin device if the cache is full. Unfortunately, it doesn't forward flush requests to the origin device, so that there is a bug where flushes are being ignored. Fix this by adding missing flush forwarding. For PMEM mode, we fix this bug by disabling direct writes to the origin device, because it performs better. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Fixes: d53f1fafec9d ("dm writecache: do direct write if the cache is full") Cc: stable@vger.kernel.org # v5.7+ Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-06-15dm writecache: have ssd writeback wait if the kcopyd workqueue is busyMikulas Patocka2-0/+11
Make dm-writecache wait if the kcopyd workqueue is busy (as will happen if waiting for page allocation or inside submit_bio). This change improves performance of "mkfs.ext2" by approximately 20% on one testbed. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-06-14md/raid5: avoid device_lock in read_one_chunk()Gal Ofri1-6/+23
There is a lock contention on device_lock in read_one_chunk(). device_lock is taken to sync conf->active_aligned_reads and conf->quiesce. read_one_chunk() takes the lock, then waits for quiesce=0 (resumed) before incrementing active_aligned_reads. raid5_quiesce() takes the lock, sets quiesce=2 (in-progress), then waits for active_aligned_reads to be zero before setting quiesce=1 (suspended). Introduce a fast (lockless) path in read_one_chunk(): activate aligned read without taking device_lock. In case quiesce starts while activating the aligned-read in fast path, deactivate it and revert to old behavior (take device_lock and wait for quiesce to finish). Add smp store/load in raid5_quiesce()/read_one_chunk() respectively to gaurantee that read_one_chunk() does not miss an ongoing quiesce. My setups: 1. 8 local nvme drives (each up to 250k iops). 2. 8 ram disks (brd). Each setup with raid6 (6+2), 1024 io threads on a 96 cpu-cores (48 per socket) system. Record both iops and cpu spent on this contention with rand-read-4k. Record bw with sequential-read-128k. Note: in most cases cpu is still busy but due to "new" bottlenecks. nvme: | iops | cpu | bw ----------------------------------------------- without patch | 1.6M | ~50% | 5.5GB/s with patch | 2M (throttled) | 0% | 16GB/s (throttled) ram (brd): | iops | cpu | bw ----------------------------------------------- without patch | 2M | ~80% | 24GB/s with patch | 4M | 0% | 55GB/s CC: Song Liu <song@kernel.org> CC: Neil Brown <neilb@suse.de> Reviewed-by: NeilBrown <neilb@suse.de> Signed-off-by: Gal Ofri <gal.ofri@storing.io> Signed-off-by: Song Liu <song@kernel.org>
2021-06-14md: add comments in md_integrity_registerGuoqing Jiang1-0/+6
Given it is not obvious for the error handling, let's try to add some comments here to make it clear. Signed-off-by: Guoqing Jiang <jiangguoqing@kylinos.cn> Signed-off-by: Song Liu <song@kernel.org>
2021-06-14md: check level before create and exit io_acct_setGuoqing Jiang1-6/+14
The bio_set (io_acct_set) is used by personalities to clone bio and trace the timestamp of bio. Some personalities such as raid1/10 don't need the bio_set, so add check to not create it unconditionally. Also update the comment for md_account_bio to make it more clear. Suggested-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Guoqing Jiang <jiangguoqing@kylinos.cn> Signed-off-by: Song Liu <song@kernel.org>
2021-06-14md: Constify attribute_group structsRikard Falkeborn4-7/+7
The attribute_group structs are never modified, they're only passed to sysfs_create_group() and sysfs_remove_group(). Make them const to allow the compiler to put them in read-only memory. Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com> Signed-off-by: Song Liu <song@kernel.org>
2021-06-14md: mark some personalities as deprecatedGuoqing Jiang4-6/+6
Mark the three personalities (linear, fault and multipath) as deprecated because: 1. people can use dm multipath or nvme multipath. 2. linear is already deprecated in MODULE_ALIAS. 3. no one actively using fault. Signed-off-by: Guoqing Jiang <jiangguoqing@kylinos.cn> Signed-off-by: Song Liu <song@kernel.org>
2021-06-14md/raid10: enable io accountingGuoqing Jiang2-0/+7
For raid10, we record the start time between split bio and clone bio, and finish the accounting in the final endio. Also introduce start_time in r10bio accordingly. Signed-off-by: Guoqing Jiang <jiangguoqing@kylinos.cn> Signed-off-by: Song Liu <song@kernel.org>
2021-06-14md/raid1: enable io accountingGuoqing Jiang2-0/+8
For raid1, we record the start time between split bio and clone bio, and finish the accounting in the final endio. Also introduce start_time in r1bio accordingly. Signed-off-by: Guoqing Jiang <jiangguoqing@kylinos.cn> Signed-off-by: Song Liu <song@kernel.org>
2021-06-14md/raid1: rename print_msg with r1bio_existedGuoqing Jiang1-4/+4
The caller of raid1_read_request could pass NULL or a valid pointer for "struct r1bio *r1_bio", so it actually means whether r1_bio is existed or not. Signed-off-by: Guoqing Jiang <jiangguoqing@kylinos.cn> Signed-off-by: Song Liu <song@kernel.org>
2021-06-14md/raid5: avoid redundant bio clone in raid5_read_one_chunkGuoqing Jiang1-14/+15
After enable io accounting, chunk read bio could be cloned twice which is not good. To avoid such inefficiency, let's clone align_bio from io_acct_set too, then we need only call md_account_bio in make_request unconditionally. Signed-off-by: Guoqing Jiang <jiangguoqing@kylinos.cn> Signed-off-by: Song Liu <song@kernel.org>
2021-06-14md/raid5: move checking badblock before clone bio in raid5_read_one_chunkGuoqing Jiang1-7/+7
We don't need to clone bio if the relevant region has badblock. Signed-off-by: Guoqing Jiang <jiangguoqing@kylinos.cn> Signed-off-by: Song Liu <song@kernel.org>
2021-06-14md: add io accounting for raid0 and raid5Guoqing Jiang4-3/+68
We introduce a new bioset (io_acct_set) for raid0 and raid5 since they don't own clone infrastructure to accounting io. And the bioset is added to mddev instead of to raid0 and raid5 layer, because with this way, we can put common functions to md.h and reuse them in raid0 and raid5. Also struct md_io_acct is added accordingly which includes io start_time, the origin bio and cloned bio. Then we can call bio_{start,end}_io_acct to get related io status. Signed-off-by: Guoqing Jiang <jiangguoqing@kylinos.cn> Signed-off-by: Song Liu <song@kernel.org>
2021-06-14md: revert io stats accountingGuoqing Jiang2-46/+0
The commit 41d2d848e5c0 ("md: improve io stats accounting") could cause double fault problem per the report [1], and also it is not correct to change ->bi_end_io if md don't own it, so let's revert it. And io stats accounting will be replemented in later commits. [1]. https://lore.kernel.org/linux-raid/3bf04253-3fad-434a-63a7-20214e38cf26@gmail.com/T/#t Fixes: 41d2d848e5c0 ("md: improve io stats accounting") Signed-off-by: Guoqing Jiang <jiangguoqing@kylinos.cn> Signed-off-by: Song Liu <song@kernel.org>
2021-06-14dm writecache: use list_move instead of list_del/list_add in ↵Baokun Li1-6/+3
writecache_writeback() Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: Baokun Li <libaokun1@huawei.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-06-14dm writecache: commit just one block, not a full pageMikulas Patocka1-5/+1
Some architectures have pages larger than 4k and committing a full page causes needless overhead. Fix this by writing a single block when committing the superblock. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-06-14dm writecache: remove unused gfp_t argument from wc_add_block()Mikulas Patocka1-3/+3
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-06-12Merge tag 'block-5.13-2021-06-12' of git://git.kernel.dk/linux-blockLinus Torvalds5-33/+7
Pull block fixes from Jens Axboe: "A few fixes that should go into 5.13: - Fix a regression deadlock introduced in this release between open and remove of a bdev (Christoph) - Fix an async_xor md regression in this release (Xiao) - Fix bcache oversized read issue (Coly)" * tag 'block-5.13-2021-06-12' of git://git.kernel.dk/linux-block: block: loop: fix deadlock between open and remove async_xor: check src_offs is not NULL before updating it bcache: avoid oversized read request in cache missing code path bcache: remove bcache device self-defined readahead
2021-06-11blk-mq: improve the blk_mq_init_allocated_queue interfaceChristoph Hellwig1-6/+3
Don't return the passed in request_queue but a normal error code, and drop the elevator_init argument in favor of just calling elevator_init_mq directly from dm-rq. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> Link: https://lore.kernel.org/r/20210602065345.355274-3-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-08bcache: avoid oversized read request in cache missing code pathColy Li1-2/+7
In the cache missing code path of cached device, if a proper location from the internal B+ tree is matched for a cache miss range, function cached_dev_cache_miss() will be called in cache_lookup_fn() in the following code block, [code block 1] 526 unsigned int sectors = KEY_INODE(k) == s->iop.inode 527 ? min_t(uint64_t, INT_MAX, 528 KEY_START(k) - bio->bi_iter.bi_sector) 529 : INT_MAX; 530 int ret = s->d->cache_miss(b, s, bio, sectors); Here s->d->cache_miss() is the call backfunction pointer initialized as cached_dev_cache_miss(), the last parameter 'sectors' is an important hint to calculate the size of read request to backing device of the missing cache data. Current calculation in above code block may generate oversized value of 'sectors', which consequently may trigger 2 different potential kernel panics by BUG() or BUG_ON() as listed below, 1) BUG_ON() inside bch_btree_insert_key(), [code block 2] 886 BUG_ON(b->ops->is_extents && !KEY_SIZE(k)); 2) BUG() inside biovec_slab(), [code block 3] 51 default: 52 BUG(); 53 return NULL; All the above panics are original from cached_dev_cache_miss() by the oversized parameter 'sectors'. Inside cached_dev_cache_miss(), parameter 'sectors' is used to calculate the size of data read from backing device for the cache missing. This size is stored in s->insert_bio_sectors by the following lines of code, [code block 4] 909 s->insert_bio_sectors = min(sectors, bio_sectors(bio) + reada); Then the actual key inserting to the internal B+ tree is generated and stored in s->iop.replace_key by the following lines of code, [code block 5] 911 s->iop.replace_key = KEY(s->iop.inode, 912 bio->bi_iter.bi_sector + s->insert_bio_sectors, 913 s->insert_bio_sectors); The oversized parameter 'sectors' may trigger panic 1) by BUG_ON() from the above code block. And the bio sending to backing device for the missing data is allocated with hint from s->insert_bio_sectors by the following lines of code, [code block 6] 926 cache_bio = bio_alloc_bioset(GFP_NOWAIT, 927 DIV_ROUND_UP(s->insert_bio_sectors, PAGE_SECTORS), 928 &dc->disk.bio_split); The oversized parameter 'sectors' may trigger panic 2) by BUG() from the agove code block. Now let me explain how the panics happen with the oversized 'sectors'. In code block 5, replace_key is generated by macro KEY(). From the definition of macro KEY(), [code block 7] 71 #define KEY(inode, offset, size) \ 72 ((struct bkey) { \ 73 .high = (1ULL << 63) | ((__u64) (size) << 20) | (inode), \ 74 .low = (offset) \ 75 }) Here 'size' is 16bits width embedded in 64bits member 'high' of struct bkey. But in code block 1, if "KEY_START(k) - bio->bi_iter.bi_sector" is very probably to be larger than (1<<16) - 1, which makes the bkey size calculation in code block 5 is overflowed. In one bug report the value of parameter 'sectors' is 131072 (= 1 << 17), the overflowed 'sectors' results the overflowed s->insert_bio_sectors in code block 4, then makes size field of s->iop.replace_key to be 0 in code block 5. Then the 0- sized s->iop.replace_key is inserted into the internal B+ tree as cache missing check key (a special key to detect and avoid a racing between normal write request and cache missing read request) as, [code block 8] 915 ret = bch_btree_insert_check_key(b, &s->op, &s->iop.replace_key); Then the 0-sized s->iop.replace_key as 3rd parameter triggers the bkey size check BUG_ON() in code block 2, and causes the kernel panic 1). Another kernel panic is from code block 6, is by the bvecs number oversized value s->insert_bio_sectors from code block 4, min(sectors, bio_sectors(bio) + reada) There are two possibility for oversized reresult, - bio_sectors(bio) is valid, but bio_sectors(bio) + reada is oversized. - sectors < bio_sectors(bio) + reada, but sectors is oversized. From a bug report the result of "DIV_ROUND_UP(s->insert_bio_sectors, PAGE_SECTORS)" from code block 6 can be 344, 282, 946, 342 and many other values which larther than BIO_MAX_VECS (a.k.a 256). When calling bio_alloc_bioset() with such larger-than-256 value as the 2nd parameter, this value will eventually be sent to biovec_slab() as parameter 'nr_vecs' in following code path, bio_alloc_bioset() ==> bvec_alloc() ==> biovec_slab() Because parameter 'nr_vecs' is larger-than-256 value, the panic by BUG() in code block 3 is triggered inside biovec_slab(). From the above analysis, we know that the 4th parameter 'sector' sent into cached_dev_cache_miss() may cause overflow in code block 5 and 6, and finally cause kernel panic in code block 2 and 3. And if result of bio_sectors(bio) + reada exceeds valid bvecs number, it may also trigger kernel panic in code block 3 from code block 6. Now the almost-useless readahead size for cache missing request back to backing device is removed, this patch can fix the oversized issue with more simpler method. - add a local variable size_limit, set it by the minimum value from the max bkey size and max bio bvecs number. - set s->insert_bio_sectors by the minimum value from size_limit, sectors, and the sectors size of bio. - replace sectors by s->insert_bio_sectors to do bio_next_split. By the above method with size_limit, s->insert_bio_sectors will never result oversized replace_key size or bio bvecs number. And split bio 'miss' from bio_next_split() will always match the size of 'cache_bio', that is the current maximum bio size we can sent to backing device for fetching the cache missing data. Current problmatic code can be partially found since Linux v3.13-rc1, therefore all maintained stable kernels should try to apply this fix. Reported-by: Alexander Ullrich <ealex1979@gmail.com> Reported-by: Diego Ercolani <diego.ercolani@gmail.com> Reported-by: Jan Szubiak <jan.szubiak@linuxpolska.pl> Reported-by: Marco Rebhan <me@dblsaiko.net> Reported-by: Matthias Ferdinand <bcache@mfedv.net> Reported-by: Victor Westerhuis <victor@westerhu.is> Reported-by: Vojtech Pavlik <vojtech@suse.cz> Reported-and-tested-by: Rolf Fokkens <rolf@rolffokkens.nl> Reported-and-tested-by: Thorsten Knabe <linux@thorsten-knabe.de> Signed-off-by: Coly Li <colyli@suse.de> Cc: stable@vger.kernel.org Cc: Christoph Hellwig <hch@lst.de> Cc: Kent Overstreet <kent.overstreet@gmail.com> Cc: Nix <nix@esperi.org.uk> Cc: Takashi Iwai <tiwai@suse.com> Link: https://lore.kernel.org/r/20210607125052.21277-3-colyli@suse.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-08bcache: remove bcache device self-defined readaheadColy Li5-32/+1
For read cache missing, bcache defines a readahead size for the read I/O request to the backing device for the missing data. This readahead size is initialized to 0, and almost no one uses it to avoid unnecessary read amplifying onto backing device and write amplifying onto cache device. Considering upper layer file system code has readahead logic allready and works fine with readahead_cache_policy sysfile interface, we don't have to keep bcache self-defined readahead anymore. This patch removes the bcache self-defined readahead for cache missing request for backing device, and the readahead sysfs file interfaces are removed as well. This is the preparation for next patch to fix potential kernel panic due to oversized request in a simpler method. Reported-by: Alexander Ullrich <ealex1979@gmail.com> Reported-by: Diego Ercolani <diego.ercolani@gmail.com> Reported-by: Jan Szubiak <jan.szubiak@linuxpolska.pl> Reported-by: Marco Rebhan <me@dblsaiko.net> Reported-by: Matthias Ferdinand <bcache@mfedv.net> Reported-by: Victor Westerhuis <victor@westerhu.is> Reported-by: Vojtech Pavlik <vojtech@suse.cz> Reported-and-tested-by: Rolf Fokkens <rolf@rolffokkens.nl> Reported-and-tested-by: Thorsten Knabe <linux@thorsten-knabe.de> Signed-off-by: Coly Li <colyli@suse.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Cc: stable@vger.kernel.org Cc: Kent Overstreet <kent.overstreet@gmail.com> Cc: Nix <nix@esperi.org.uk> Cc: Takashi Iwai <tiwai@suse.com> Link: https://lore.kernel.org/r/20210607125052.21277-2-colyli@suse.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-04dm crypt: Fix zoned block device supportDamien Le Moal1-5/+19
Zone append BIOs (REQ_OP_ZONE_APPEND) always specify the start sector of the zone to be written instead of the actual sector location to write. The write location is determined by the device and returned to the host upon completion of the operation. This interface, while simple and efficient for writing into sequential zones of a zoned block device, is incompatible with the use of sector values to calculate a cypher block IV. All data written in a zone end up using the same IV values corresponding to the first sectors of the zone, but read operation will specify any sector within the zone resulting in an IV mismatch between encryption and decryption. To solve this problem, report to DM core that zone append operations are not supported. This result in the zone append operations being emulated using regular write operations. Reported-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com> Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-06-04dm: introduce zone append emulationDamien Le Moal5-54/+612
For zoned targets that cannot support zone append operations, implement an emulation using regular write operations. If the original BIO submitted by the user is a zone append operation, change its clone into a regular write operation directed at the target zone write pointer position. To do so, an array of write pointer offsets (write pointer position relative to the start of a zone) is added to struct mapped_device. All operations that modify a sequential zone write pointer (writes, zone reset, zone finish and zone append) are intersepted in __map_bio() and processed using the new functions dm_zone_map_bio(). Detection of the target ability to natively support zone append operations is done from dm_table_set_restrictions() by calling the function dm_set_zones_restrictions(). A target that does not support zone append operation, either by explicitly declaring it using the new struct dm_target field zone_append_not_supported, or because the device table contains a non-zoned device, has its mapped device marked with the new flag DMF_ZONE_APPEND_EMULATED. The helper function dm_emulate_zone_append() is introduced to test a mapped device for this new flag. Atomicity of the zones write pointer tracking and updates is done using a zone write locking mechanism based on a bitmap. This is similar to the block layer method but based on BIOs rather than struct request. A zone write lock is taken in dm_zone_map_bio() for any clone BIO with an operation type that changes the BIO target zone write pointer position. The zone write lock is released if the clone BIO is failed before submission or when dm_zone_endio() is called when the clone BIO completes. The zone write lock bitmap of the mapped device, together with a bitmap indicating zone types (conv_zones_bitmap) and the write pointer offset array (zwp_offset) are allocated and initialized with a full device zone report in dm_set_zones_restrictions() using the function dm_revalidate_zones(). For failed operations that may have modified a zone write pointer, the zone write pointer offset is marked as invalid in dm_zone_endio(). Zones with an invalid write pointer offset are checked and the write pointer updated using an internal report zone operation when the faulty zone is accessed again by the user. All functions added for this emulation have a minimal overhead for zoned targets natively supporting zone append operations. Regular device targets are also not affected. The added code also does not impact builds with CONFIG_BLK_DEV_ZONED disabled by stubbing out all dm zone related functions. Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com> Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-06-04dm: rearrange core declarations for extended use from dm-zone.cDamien Le Moal2-52/+59
Move the definitions of struct dm_target_io, struct dm_io and the bits of the flags field of struct mapped_device from dm.c to dm-core.h to make them usable from dm-zone.c. For the same reason, declare dec_pending() in dm-core.h after renaming it to dm_io_dec_pending(). And for symmetry of the function names, introduce the inline helper dm_io_inc_pending() instead of directly using atomic_inc() calls. Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-06-04dm: Forbid requeue of writes to zonesDamien Le Moal3-6/+41
A target map method requesting the requeue of a bio with DM_MAPIO_REQUEUE or completing it with DM_ENDIO_REQUEUE can cause unaligned write errors if the bio is a write operation targeting a sequential zone. If a zoned target request such a requeue, warn about it and kill the IO. The function dm_is_zone_write() is introduced to detect write operations to zoned targets. This change does not affect the target drivers supporting zoned devices and exposing a zoned device, namely dm-crypt, dm-linear and dm-flakey as none of these targets ever request a requeue. Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-06-04dm: Introduce dm_report_zones()Damien Le Moal4-14/+29
To simplify the implementation of the report_zones operation of a zoned target, introduce the function dm_report_zones() to set a target mapping start sector in struct dm_report_zones_args and call blkdev_report_zones(). This new function is exported and the report zones callback function dm_report_zones_cb() is not. dm-linear, dm-flakey and dm-crypt are modified to use dm_report_zones(). Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-06-04dm: move zone related code to dm-zone.cDamien Le Moal5-89/+119
Move core and table code used for zoned targets and conditionally defined with #ifdef CONFIG_BLK_DEV_ZONED to the new file dm-zone.c. This file is conditionally compiled depending on CONFIG_BLK_DEV_ZONED. The small helper dm_set_zones_restrictions() is introduced to initialize a mapped device request queue zone attributes in dm_table_set_restrictions(). Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-06-04dm: cleanup device_area_is_invalid()Damien Le Moal1-1/+1
In device_area_is_invalid(), use bdev_is_zoned() instead of open coding the test on the zoned model returned by bdev_zoned_model(). Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-06-04dm: Fix dm_accept_partial_bio() relative to zone management commandsDamien Le Moal1-2/+6
Fix dm_accept_partial_bio() to actually check that zone management commands are not passed as explained in the function documentation comment. Also, since a zone append operation cannot be split, add REQ_OP_ZONE_APPEND as a forbidden command. White lines are added around the group of BUG_ON() calls to make the code more legible. Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-06-04dm zoned: check zone capacityDamien Le Moal1-0/+7
The dm-zoned target cannot support zoned block devices with zones that have a capacity smaller than the zone size (e.g. NVMe zoned namespaces) due to the current chunk zone mapping implementation as it is assumed that zones and chunks have the same size with all blocks usable. If a zoned drive is found to have zones with a capacity different from the zone size, fail the target initialization. Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com> Cc: stable@vger.kernel.org # v5.9+ Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-06-04dm table: Constify static struct blk_ksm_ll_opsRikard Falkeborn1-1/+1
The only usage of dm_ksm_ll_ops is to make a copy of it to the ksm_ll_ops field in the blk_keyslot_manager struct. Make it const to allow the compiler to put it in read-only memory. Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-06-04dm writecache: interrupt writeback if suspendedMikulas Patocka1-2/+3
If the DM device is suspended, interrupt the writeback sequence so that there is no excessive suspend delay. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-06-04dm writecache: don't split bios when overwriting contiguous cache contentMikulas Patocka1-8/+30
If dm-writecache overwrites existing cached data, it splits the incoming bio into many block-sized bios. The I/O scheduler does merge these bios into one large request but this needless splitting and merging causes performance degradation. Fix this by avoiding bio splitting if the cache target area that is being overwritten is contiguous. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-06-04dm kcopyd: avoid spin_lock_irqsave from process contextMikulas Patocka1-9/+6
The functions "pop", "push_head", "do_work" can only be called from process context. Therefore, replace spin_lock_irq{save,restore} with spin_{lock,unlock}_irq. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-06-04dm kcopyd: avoid useless atomic operationsMikulas Patocka3-12/+12
The functions set_bit and clear_bit are atomic. We don't need atomicity when making flags for dm-kcopyd. So, change them to direct manipulation of the flags. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-06-04dm space map disk: cache a small number of index entriesJoe Thornber2-6/+96
The disk space map stores it's index entries in a btree, these are accessed very frequently, so having a few cached makes a big difference to performance. With this change provisioning a new block takes roughly 20% less cpu. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-06-04dm space maps: improve performance with inc/dec on ranges of blocksJoe Thornber15-245/+774
When we break sharing on btree nodes we typically need to increment the reference counts to every value held in the node. This can cause a lot of repeated calls to the space maps. Fix this by changing the interface to the space map inc/dec methods to take ranges of adjacent blocks to be operated on. For installations that are using a lot of snapshots this will reduce cpu overhead of fundamental operations such as provisioning a new block, or deleting a snapshot, by as much as 10 times. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-06-04dm space maps: don't reset space map allocation cursor when committingJoe Thornber2-2/+16
Current commit code resets the place where the search for free blocks will begin back to the start of the metadata device. There are a couple of repercussions to this: - The first allocation after the commit is likely to take longer than normal as it searches for a free block in an area that is likely to have very few free blocks (if any). - Any free blocks it finds will have been recently freed. Reusing them means we have fewer old copies of the metadata to aid recovery from hardware error. Fix these issues by leaving the cursor alone, only resetting when the search hits the end of the metadata device. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>