summaryrefslogtreecommitdiff
path: root/drivers/md/bcache/request.c
AgeCommit message (Collapse)AuthorFilesLines
2023-11-24closures: CLOSURE_CALLBACK() to fix type punningKent Overstreet1-37/+37
Control flow integrity is now checking that type signatures match on indirect function calls. That breaks closures, which embed a work_struct in a closure in such a way that a closure_fn may also be used as a workqueue fn by the underlying closure code. So we have to change closure fns to take a work_struct as their argument - but that results in a loss of clarity, as closure fns have different semantics from normal workqueue functions (they run owning a ref on the closure, which must be released with continue_at() or closure_return()). Thus, this patc introduces CLOSURE_CALLBACK() and closure_type() macros as suggested by Kees, to smooth things over a bit. Suggested-by: Kees Cook <keescook@chromium.org> Cc: Coly Li <colyli@suse.de> Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-06-12block: replace fmode_t with a block-specific type for block open flagsChristoph Hellwig1-2/+2
The only overlap between the block open flags mapped into the fmode_t and other uses of fmode_t are FMODE_READ and FMODE_WRITE. Define a new blk_mode_t instead for use in blkdev_get_by_{dev,path}, ->open and ->ioctl and stop abusing fmode_t. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Jack Wang <jinpu.wang@ionos.com> [rnbd] Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Christian Brauner <brauner@kernel.org> Link: https://lore.kernel.org/r/20230608110258.189493-28-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-12-13Merge tag 'for-6.2/block-2022-12-08' of git://git.kernel.dk/linuxLinus Torvalds1-1/+1
Pull block updates from Jens Axboe: - NVMe pull requests via Christoph: - Support some passthrough commands without CAP_SYS_ADMIN (Kanchan Joshi) - Refactor PCIe probing and reset (Christoph Hellwig) - Various fabrics authentication fixes and improvements (Sagi Grimberg) - Avoid fallback to sequential scan due to transient issues (Uday Shankar) - Implement support for the DEAC bit in Write Zeroes (Christoph Hellwig) - Allow overriding the IEEE OUI and firmware revision in configfs for nvmet (Aleksandr Miloserdov) - Force reconnect when number of queue changes in nvmet (Daniel Wagner) - Minor fixes and improvements (Uros Bizjak, Joel Granados, Sagi Grimberg, Christoph Hellwig, Christophe JAILLET) - Fix and cleanup nvme-fc req allocation (Chaitanya Kulkarni) - Use the common tagset helpers in nvme-pci driver (Christoph Hellwig) - Cleanup the nvme-pci removal path (Christoph Hellwig) - Use kstrtobool() instead of strtobool (Christophe JAILLET) - Allow unprivileged passthrough of Identify Controller (Joel Granados) - Support io stats on the mpath device (Sagi Grimberg) - Minor nvmet cleanup (Sagi Grimberg) - MD pull requests via Song: - Code cleanups (Christoph) - Various fixes - Floppy pull request from Denis: - Fix a memory leak in the init error path (Yuan) - Series fixing some batch wakeup issues with sbitmap (Gabriel) - Removal of the pktcdvd driver that was deprecated more than 5 years ago, and subsequent removal of the devnode callback in struct block_device_operations as no users are now left (Greg) - Fix for partition read on an exclusively opened bdev (Jan) - Series of elevator API cleanups (Jinlong, Christoph) - Series of fixes and cleanups for blk-iocost (Kemeng) - Series of fixes and cleanups for blk-throttle (Kemeng) - Series adding concurrent support for sync queues in BFQ (Yu) - Series bringing drbd a bit closer to the out-of-tree maintained version (Christian, Joel, Lars, Philipp) - Misc drbd fixes (Wang) - blk-wbt fixes and tweaks for enable/disable (Yu) - Fixes for mq-deadline for zoned devices (Damien) - Add support for read-only and offline zones for null_blk (Shin'ichiro) - Series fixing the delayed holder tracking, as used by DM (Yu, Christoph) - Series enabling bio alloc caching for IRQ based IO (Pavel) - Series enabling userspace peer-to-peer DMA (Logan) - BFQ waker fixes (Khazhismel) - Series fixing elevator refcount issues (Christoph, Jinlong) - Series cleaning up references around queue destruction (Christoph) - Series doing quiesce by tagset, enabling cleanups in drivers (Christoph, Chao) - Series untangling the queue kobject and queue references (Christoph) - Misc fixes and cleanups (Bart, David, Dawei, Jinlong, Kemeng, Ye, Yang, Waiman, Shin'ichiro, Randy, Pankaj, Christoph) * tag 'for-6.2/block-2022-12-08' of git://git.kernel.dk/linux: (247 commits) blktrace: Fix output non-blktrace event when blk_classic option enabled block: sed-opal: Don't include <linux/kernel.h> sed-opal: allow using IOC_OPAL_SAVE for locking too blk-cgroup: Fix typo in comment block: remove bio_set_op_attrs nvmet: don't open-code NVME_NS_ATTR_RO enumeration nvme-pci: use the tagset alloc/free helpers nvme: add the Apple shared tag workaround to nvme_alloc_io_tag_set nvme: only set reserved_tags in nvme_alloc_io_tag_set for fabrics controllers nvme: consolidate setting the tagset flags nvme: pass nr_maps explicitly to nvme_alloc_io_tag_set block: bio_copy_data_iter nvme-pci: split out a nvme_pci_ctrl_is_dead helper nvme-pci: return early on ctrl state mismatch in nvme_reset_work nvme-pci: rename nvme_disable_io_queues nvme-pci: cleanup nvme_suspend_queue nvme-pci: remove nvme_pci_disable nvme-pci: remove nvme_disable_admin_queue nvme: merge nvme_shutdown_ctrl into nvme_disable_ctrl nvme: use nvme_wait_ready in nvme_shutdown_ctrl ...
2022-12-07block: remove bio_set_op_attrsChristoph Hellwig1-1/+1
This macro is obsolete, so replace the last few uses with open coded bi_opf assignments. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Coly Li <colyli@suse.de <mailto:colyli@suse.de>> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Link: https://lore.kernel.org/r/20221206144057.720846-1-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-11-18treewide: use get_random_u32_below() instead of deprecated functionJason A. Donenfeld1-1/+1
This is a simple mechanical transformation done by: @@ expression E; @@ - prandom_u32_max + get_random_u32_below (E) Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Darrick J. Wong <djwong@kernel.org> # for xfs Reviewed-by: SeongJae Park <sj@kernel.org> # for damon Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> # for infiniband Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> # for arm Acked-by: Ulf Hansson <ulf.hansson@linaro.org> # for mmc Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2022-10-12treewide: use prandom_u32_max() when possible, part 1Jason A. Donenfeld1-1/+1
Rather than incurring a division or requesting too many random bytes for the given range, use the prandom_u32_max() function, which only takes the minimum required bytes from the RNG and avoids divisions. This was done mechanically with this coccinelle script: @basic@ expression E; type T; identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32"; typedef u64; @@ ( - ((T)get_random_u32() % (E)) + prandom_u32_max(E) | - ((T)get_random_u32() & ((E) - 1)) + prandom_u32_max(E * XXX_MAKE_SURE_E_IS_POW2) | - ((u64)(E) * get_random_u32() >> 32) + prandom_u32_max(E) | - ((T)get_random_u32() & ~PAGE_MASK) + prandom_u32_max(PAGE_SIZE) ) @multi_line@ identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32"; identifier RAND; expression E; @@ - RAND = get_random_u32(); ... when != RAND - RAND %= (E); + RAND = prandom_u32_max(E); // Find a potential literal @literal_mask@ expression LITERAL; type T; identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32"; position p; @@ ((T)get_random_u32()@p & (LITERAL)) // Add one to the literal. @script:python add_one@ literal << literal_mask.LITERAL; RESULT; @@ value = None if literal.startswith('0x'): value = int(literal, 16) elif literal[0] in '123456789': value = int(literal, 10) if value is None: print("I don't know how to handle %s" % (literal)) cocci.include_match(False) elif value == 2**32 - 1 or value == 2**31 - 1 or value == 2**24 - 1 or value == 2**16 - 1 or value == 2**8 - 1: print("Skipping 0x%x for cleanup elsewhere" % (value)) cocci.include_match(False) elif value & (value + 1) != 0: print("Skipping 0x%x because it's not a power of two minus one" % (value)) cocci.include_match(False) elif literal.startswith('0x'): coccinelle.RESULT = cocci.make_expr("0x%x" % (value + 1)) else: coccinelle.RESULT = cocci.make_expr("%d" % (value + 1)) // Replace the literal mask with the calculated result. @plus_one@ expression literal_mask.LITERAL; position literal_mask.p; expression add_one.RESULT; identifier FUNC; @@ - (FUNC()@p & (LITERAL)) + prandom_u32_max(RESULT) @collapse_ret@ type T; identifier VAR; expression E; @@ { - T VAR; - VAR = (E); - return VAR; + return E; } @drop_var@ type T; identifier VAR; @@ { - T VAR; ... when != VAR } Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Yury Norov <yury.norov@gmail.com> Reviewed-by: KP Singh <kpsingh@kernel.org> Reviewed-by: Jan Kara <jack@suse.cz> # for ext4 and sbitmap Reviewed-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com> # for drbd Acked-by: Jakub Kicinski <kuba@kernel.org> Acked-by: Heiko Carstens <hca@linux.ibm.com> # for s390 Acked-by: Ulf Hansson <ulf.hansson@linaro.org> # for mmc Acked-by: Darrick J. Wong <djwong@kernel.org> # for xfs Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2022-06-03Merge tag 'for-5.19/drivers-2022-06-02' of git://git.kernel.dk/linux-blockLinus Torvalds1-0/+6
Pull more block driver updates from Jens Axboe: "A collection of stragglers that were late on sending in their changes and just followup fixes. - NVMe fixes pull request via Christoph: - set controller enable bit in a separate write (Niklas Cassel) - disable namespace identifiers for the MAXIO MAP1001 (Christoph) - fix a comment typo (Julia Lawall)" - MD fixes pull request via Song: - Remove uses of bdevname (Christoph Hellwig) - Bug fixes (Guoqing Jiang, and Xiao Ni) - bcache fixes series (Coly) - null_blk zoned write fix (Damien) - nbd fixes (Yu, Zhang) - Fix for loop partition scanning (Christoph)" * tag 'for-5.19/drivers-2022-06-02' of git://git.kernel.dk/linux-block: (23 commits) block: null_blk: Fix null_zone_write() nvmet: fix typo in comment nvme: set controller enable bit in a separate write nvme-pci: disable namespace identifiers for the MAXIO MAP1001 bcache: avoid unnecessary soft lockup in kworker update_writeback_rate() nbd: use pr_err to output error message nbd: fix possible overflow on 'first_minor' in nbd_dev_add() nbd: fix io hung while disconnecting device nbd: don't clear 'NBD_CMD_INFLIGHT' flag if request is not completed nbd: fix race between nbd_alloc_config() and module removal nbd: call genl_unregister_family() first in nbd_cleanup() md: bcache: check the return value of kzalloc() in detached_dev_do_request() bcache: memset on stack variables in bch_btree_check() and bch_sectors_dirty_init() block, loop: support partitions without scanning bcache: avoid journal no-space deadlock by reserving 1 journal bucket bcache: remove incremental dirty sector counting for bch_sectors_dirty_init() bcache: improve multithreaded bch_sectors_dirty_init() bcache: improve multithreaded bch_btree_check() md: fix double free of io_acct_set bioset md: Don't set mddev private to NULL in raid0 pers->free ...
2022-05-27md: bcache: check the return value of kzalloc() in detached_dev_do_request()Jia-Ju Bai1-0/+6
The function kzalloc() in detached_dev_do_request() can fail, so its return value should be checked. Fixes: bc082a55d25c ("bcache: fix inaccurate io state for detached bcache devices") Reported-by: TOTE Robot <oslab@tsinghua.edu.cn> Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com> Signed-off-by: Coly Li <colyli@suse.de> Link: https://lore.kernel.org/r/20220527152818.27545-4-colyli@suse.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-05-23Merge tag 'for-5.19/block-2022-05-22' of git://git.kernel.dk/linux-blockLinus Torvalds1-2/+2
Pull block updates from Jens Axboe: "Here are the core block changes for 5.19. This contains: - blk-throttle accounting fix (Laibin) - Series removing redundant assignments (Michal) - Expose bio cache via the bio_set, so that DM can use it (Mike) - Finish off the bio allocation interface cleanups by dealing with the weirdest member of the family. bio_kmalloc combines a kmalloc for the bio and bio_vecs with a hidden bio_init call and magic cleanup semantics (Christoph) - Clean up the block layer API so that APIs consumed by file systems are (almost) only struct block_device based, so that file systems don't have to poke into block layer internals like the request_queue (Christoph) - Clean up the blk_execute_rq* API (Christoph) - Clean up various lose end in the blk-cgroup code to make it easier to follow in preparation of reworking the blkcg assignment for bios (Christoph) - Fix use-after-free issues in BFQ when processes with merged queues get moved to different cgroups (Jan) - BFQ fixes (Jan) - Various fixes and cleanups (Bart, Chengming, Fanjun, Julia, Ming, Wolfgang, me)" * tag 'for-5.19/block-2022-05-22' of git://git.kernel.dk/linux-block: (83 commits) blk-mq: fix typo in comment bfq: Remove bfq_requeue_request_body() bfq: Remove superfluous conversion from RQ_BIC() bfq: Allow current waker to defend against a tentative one bfq: Relax waker detection for shared queues blk-cgroup: delete rcu_read_lock_held() WARN_ON_ONCE() blk-throttle: Set BIO_THROTTLED when bio has been throttled blk-cgroup: Remove unnecessary rcu_read_lock/unlock() blk-cgroup: always terminate io.stat lines block, bfq: make bfq_has_work() more accurate block, bfq: protect 'bfqd->queued' by 'bfqd->lock' block: cleanup the VM accounting in submit_bio block: Fix the bio.bi_opf comment block: reorder the REQ_ flags blk-iocost: combine local_stat and desc_stat to stat block: improve the error message from bio_check_eod block: allow passing a NULL bdev to bio_alloc_clone/bio_init_clone block: remove superfluous calls to blkcg_bio_issue_init kthread: unexport kthread_blkcg blk-cgroup: cleanup blkcg_maybe_throttle_current ...
2022-04-19bcache: fix wrong bdev parameter when calling bio_alloc_clone() in do_bio_hook()Coly Li1-1/+1
Commit abfc426d1b2f ("block: pass a block_device to bio_clone_fast") calls the modified bio_alloc_clone() in bcache code as: bio_init_clone(bio->bi_bdev, bio, orig_bio, GFP_NOIO); But the first parameter is wrong, where bio->bi_bdev should be orig_bio->bi_bdev. The wrong bi_bdev panics the kernel when submitting cache bio. This patch fixes the wrong bdev parameter usage and avoid the panic. Fixes: abfc426d1b2f ("block: pass a block_device to bio_clone_fast") Signed-off-by: Coly Li <colyli@suse.de> Cc: Christoph Hellwig <hch@lst.de> Cc: Mike Snitzer <snitzer@redhat.com> Link: https://lore.kernel.org/r/20220419160425.4148-3-colyli@suse.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-04-18block: remove QUEUE_FLAG_DISCARDChristoph Hellwig1-2/+2
Just use a non-zero max_discard_sectors as an indicator for discard support, similar to what is done for write zeroes. The only places where needs special attention is the RAID5 driver, which must clear discard support for security reasons by default, even if the default stacking rules would allow for it. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Acked-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com> [drbd] Acked-by: Jan Höppner <hoeppner@linux.ibm.com> [s390] Acked-by: Coly Li <colyli@suse.de> [bcache] Acked-by: David Sterba <dsterba@suse.com> [btrfs] Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Link: https://lore.kernel.org/r/20220415045258.199825-25-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-03-04bcache: use bvec_kmap_local in bio_csumChristoph Hellwig1-2/+2
Using local kmaps slightly reduces the chances to stray writes, and the bvec interface cleans up the code a little bit. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Link: https://lore.kernel.org/r/20220303111905.321089-8-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-02-04block: pass a block_device to bio_clone_fastChristoph Hellwig1-2/+3
Pass a block_device to bio_clone_fast and __bio_clone_fast and give the functions more suitable names. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Mike Snitzer <snitzer@redhat.com> Link: https://lore.kernel.org/r/20220202160109.108149-14-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-02-04block: initialize the target bio in __bio_clone_fastChristoph Hellwig1-1/+0
All callers of __bio_clone_fast initialize the bio first. Move that initialization into __bio_clone_fast instead. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Mike Snitzer <snitzer@redhat.com> Link: https://lore.kernel.org/r/20220202160109.108149-13-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-02-04block: clone crypto and integrity data in __bio_clone_fastChristoph Hellwig1-1/+1
__bio_clone_fast should also clone integrity and crypto data, as a clone without those is incomplete. Right now the only caller that can actually support crypto and integrity data (dm) does it manually for the one callchain that supports these, but we better do it properly in the core. Note that all callers except for the above mentioned one also don't need to handle failure at all, given that the integrity and crypto clones are based on mempool allocations that won't fail for sleeping allocations. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Mike Snitzer <snitzer@redhat.com> Link: https://lore.kernel.org/r/20220202160109.108149-11-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-02-02block: pass a block_device and opf to bio_resetChristoph Hellwig1-2/+2
Pass the block_device that we plan to use this bio for and the operation to bio_reset to optimize the assigment. A NULL block_device can be passed, both for the passthrough case on a raw request_queue and to temporarily avoid refactoring some nasty code. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Link: https://lore.kernel.org/r/20220124091107.642561-20-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-02-02block: pass a block_device and opf to bio_initChristoph Hellwig1-1/+1
Pass the block_device that we plan to use this bio for and the operation to bio_init to optimize the assignment. A NULL block_device can be passed, both for the passthrough case on a raw request_queue and to temporarily avoid refactoring some nasty code. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Link: https://lore.kernel.org/r/20220124091107.642561-19-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-02-02block: pass a block_device and opf to bio_alloc_biosetChristoph Hellwig1-7/+5
Pass the block_device and operation that we plan to use this bio for to bio_alloc_bioset to optimize the assigment. NULL/0 can be passed, both for the passthrough case on a raw request_queue and to temporarily avoid refactoring some nasty code. Also move the gfp_mask argument after the nr_vecs argument for a much more logical calling convention matching what most of the kernel does. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Link: https://lore.kernel.org/r/20220124091107.642561-16-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-20bcache: remove bch_crc64_updateChristoph Hellwig1-1/+1
bch_crc64_update is an entirely pointless wrapper around crc64_be. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Coly Li <colyli@suse.de> Link: https://lore.kernel.org/r/20211020143812.6403-9-colyli@suse.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-20bcache: remove the backing_dev_name field from struct cached_devChristoph Hellwig1-2/+2
Just use the %pg format specifier to print the name directly. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Coly Li <colyli@suse.de> Link: https://lore.kernel.org/r/20211020143812.6403-7-colyli@suse.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-18block: switch polling to be bio basedChristoph Hellwig1-8/+5
Replace the blk_poll interface that requires the caller to keep a queue and cookie from the submissions with polling based on the bio. Polling for the bio itself leads to a few advantages: - the cookie construction can made entirely private in blk-mq.c - the caller does not need to remember the request_queue and cookie separately and thus sidesteps their lifetime issues - keeping the device and the cookie inside the bio allows to trivially support polling BIOs remapping by stacking drivers - a lot of code to propagate the cookie back up the submission path can be removed entirely. Signed-off-by: Christoph Hellwig <hch@lst.de> Tested-by: Mark Wunderlich <mark.wunderlich@intel.com> Link: https://lore.kernel.org/r/20211012111226.760968-15-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-09bcache: 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>
2021-06-09bcache: remove bcache device self-defined readaheadColy Li1-12/+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>
2021-01-25block: use ->bi_bdev for bio based I/O accountingChristoph Hellwig1-13/+21
Rework the I/O accounting for bio based drivers to use ->bi_bdev. This means all drivers can now simply use bio_start_io_acct to start accounting, and it will take partitions into account automatically. To end I/O account either bio_end_io_acct can be used if the driver never remaps I/O to a different device, or bio_end_io_acct_remapped if the driver did remap the I/O. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-01-25block: store a block_device pointer in struct bioChristoph Hellwig1-3/+4
Replace the gendisk pointer in struct bio with a pointer to the newly improved struct block device. From that the gendisk can be trivially accessed with an extra indirection, but it also allows to directly look up all information related to partition remapping. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-12-02block: switch partition lookup to use struct block_deviceChristoph Hellwig1-2/+2
Use struct block_device to lookup partitions on a disk. This removes all usage of struct hd_struct from the I/O path. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Hannes Reinecke <hare@suse.de> Acked-by: Coly Li <colyli@suse.de> [bcache] Acked-by: Chao Yu <yuchao0@huawei.com> [f2fs] Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-11-16block: remove __blkdev_driver_ioctlChristoph Hellwig1-2/+3
Just open code it in the few callers. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-10-02bcache: remove embedded struct cache_sb from struct cache_setColy Li1-2/+2
Since bcache code was merged into mainline kerrnel, each cache set only as one single cache in it. The multiple caches framework is here but the code is far from completed. Considering the multiple copies of cached data can also be stored on e.g. md raid1 devices, it is unnecessary to support multiple caches in one cache set indeed. The previous preparation patches fix the dependencies of explicitly making a cache set only have single cache. Now we don't have to maintain an embedded partial super block in struct cache_set, the in-memory super block can be directly referenced from struct cache. This patch removes the embedded struct cache_sb from struct cache_set, and fixes all locations where the superb lock was referenced from this removed super block by referencing the in-memory super block of struct cache. Signed-off-by: Coly Li <colyli@suse.de> Reviewed-by: Hannes Reinecke <hare@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-10-02bcache: only use block_bytes() on struct cacheColy Li1-1/+1
Because struct cache_set and struct cache both have struct cache_sb, therefore macro block_bytes() can be used on both of them. When removing the embedded struct cache_sb from struct cache_set, this macro won't be used on struct cache_set anymore. This patch unifies all block_bytes() usage only on struct cache, this is one of the preparation to remove the embedded struct cache_sb from struct cache_set. Signed-off-by: Coly Li <colyli@suse.de> Reviewed-by: Hannes Reinecke <hare@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-09-12bcache: use part_[begin|end]_io_acct instead of disk_[begin|end]_io_acctSong Liu1-4/+6
This enables proper statistics in /proc/diskstats for bcache partitions. Signed-off-by: Song Liu <songliubraving@fb.com> Reviewed-by: Coly Li <colyli@suse.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-08-05Merge tag 'for-5.9/drivers-20200803' of git://git.kernel.dk/linux-blockLinus Torvalds1-5/+9
Pull block driver updates from Jens Axboe: - NVMe: - ZNS support (Aravind, Keith, Matias, Niklas) - Misc cleanups, optimizations, fixes (Baolin, Chaitanya, David, Dongli, Max, Sagi) - null_blk zone capacity support (Aravind) - MD: - raid5/6 fixes (ChangSyun) - Warning fixes (Damien) - raid5 stripe fixes (Guoqing, Song, Yufen) - sysfs deadlock fix (Junxiao) - raid10 deadlock fix (Vitaly) - struct_size conversions (Gustavo) - Set of bcache updates/fixes (Coly) * tag 'for-5.9/drivers-20200803' of git://git.kernel.dk/linux-block: (117 commits) md/raid5: Allow degraded raid6 to do rmw md/raid5: Fix Force reconstruct-write io stuck in degraded raid5 raid5: don't duplicate code for different paths in handle_stripe raid5-cache: hold spinlock instead of mutex in r5c_journal_mode_show md: print errno in super_written md/raid5: remove the redundant setting of STRIPE_HANDLE md: register new md sysfs file 'uuid' read-only md: fix max sectors calculation for super 1.0 nvme-loop: remove extra variable in create ctrl nvme-loop: set ctrl state connecting after init nvme-multipath: do not fall back to __nvme_find_path() for non-optimized paths nvme-multipath: fix logic for non-optimized paths nvme-rdma: fix controller reset hang during traffic nvme-tcp: fix controller reset hang during traffic nvmet: introduce the passthru Kconfig option nvmet: introduce the passthru configfs interface nvmet: Add passthru enable/disable helpers nvmet: add passthru code to process commands nvme: export nvme_find_get_ns() and nvme_put_ns() nvme: introduce nvme_ctrl_get_by_path() ...
2020-07-28bcache: use disk_{start,end}_io_acct() to count I/O for bcache deviceColy Li1-28/+9
This patch is a fix to patch "bcache: fix bio_{start,end}_io_acct with proper device". The previous patch uses a hack to temporarily set bi_disk to bcache device, which is mistaken too. As Christoph suggests, this patch uses disk_{start,end}_io_acct() to count I/O for bcache device in the correct way. Fixes: 85750aeb748f ("bcache: use bio_{start,end}_io_acct") Signed-off-by: Coly Li <colyli@suse.de> Cc: Christoph Hellwig <hch@lst.de> Cc: stable@vger.kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-25bcache: fix bio_{start,end}_io_acct with proper deviceColy Li1-4/+27
Commit 85750aeb748f ("bcache: use bio_{start,end}_io_acct") moves the io account code to the location after bio_set_dev(bio, dc->bdev) in cached_dev_make_request(). Then the account is performed incorrectly on backing device, indeed the I/O should be counted to bcache device like /dev/bcache0. With the mistaken I/O account, iostat does not display I/O counts for bcache device and all the numbers go to backing device. In writeback mode, the hard drive may have 340K+ IOPS which is impossible and wrong for spinning disk. This patch introduces bch_bio_start_io_acct() and bch_bio_end_io_acct(), which switches bio->bi_disk to bcache device before calling bio_start_io_acct() or bio_end_io_acct(). Now the I/Os are counted to bcache device, and bcache device, cache device and backing device have their correct I/O count information back. Fixes: 85750aeb748f ("bcache: use bio_{start,end}_io_acct") Signed-off-by: Coly Li <colyli@suse.de> Cc: Christoph Hellwig <hch@lst.de> Cc: stable@vger.kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-09writeback: remove bdi->congested_fnChristoph Hellwig1-47/+0
Except for pktdvd, the only places setting congested bits are file systems that allocate their own backing_dev_info structures. And pktdvd is a deprecated driver that isn't useful in stack setup either. So remove the dead congested_fn stacking infrastructure. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Song Liu <song@kernel.org> Acked-by: David Sterba <dsterba@suse.com> [axboe: fixup unused variables in bcache/request.c] Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-01block: rename generic_make_request to submit_bio_noacctChristoph Hellwig1-4/+3
generic_make_request has always been very confusingly misnamed, so rename it to submit_bio_noacct to make it clear that it is submit_bio minus accounting and a few checks. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-01block: move ->make_request_fn to struct block_device_operationsChristoph Hellwig1-2/+2
The make_request_fn is a little weird in that it sits directly in struct request_queue instead of an operation vector. Replace it with a block_device_operations method called submit_bio (which describes much better what it does). Also remove the request_queue argument to it, as the queue can be derived pretty trivially from the bio. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-06-03Merge tag 'for-5.8/drivers-2020-06-01' of git://git.kernel.dk/linux-blockLinus Torvalds1-3/+3
Pull block driver updates from Jens Axboe: "On top of the core changes, here are the block driver changes for this merge window: - NVMe changes: - NVMe over Fibre Channel protocol updates, which also reach over to drivers/scsi/lpfc (James Smart) - namespace revalidation support on the target (Anthony Iliopoulos) - gcc zero length array fix (Arnd Bergmann) - nvmet cleanups (Chaitanya Kulkarni) - misc cleanups and fixes (me, Keith Busch, Sagi Grimberg) - use a SRQ per completion vector (Max Gurtovoy) - fix handling of runtime changes to the queue count (Weiping Zhang) - t10 protection information support for nvme-rdma and nvmet-rdma (Israel Rukshin and Max Gurtovoy) - target side AEN improvements (Chaitanya Kulkarni) - various fixes and minor improvements all over, icluding the nvme part of the lpfc driver" - Floppy code cleanup series (Willy, Denis) - Floppy contention fix (Jiri) - Loop CONFIGURE support (Martijn) - bcache fixes/improvements (Coly, Joe, Colin) - q->queuedata cleanups (Christoph) - Get rid of ioctl_by_bdev (Christoph, Stefan) - md/raid5 allocation fixes (Coly) - zero length array fixes (Gustavo) - swim3 task state fix (Xu)" * tag 'for-5.8/drivers-2020-06-01' of git://git.kernel.dk/linux-block: (166 commits) bcache: configure the asynchronous registertion to be experimental bcache: asynchronous devices registration bcache: fix refcount underflow in bcache_device_free() bcache: Convert pr_<level> uses to a more typical style bcache: remove redundant variables i and n lpfc: Fix return value in __lpfc_nvme_ls_abort lpfc: fix axchg pointer reference after free and double frees lpfc: Fix pointer checks and comments in LS receive refactoring nvme: set dma alignment to qword nvmet: cleanups the loop in nvmet_async_events_process nvmet: fix memory leak when removing namespaces and controllers concurrently nvmet-rdma: add metadata/T10-PI support nvmet: add metadata support for block devices nvmet: add metadata/T10-PI support nvme: add Metadata Capabilities enumerations nvmet: rename nvmet_check_data_len to nvmet_check_transfer_len nvmet: rename nvmet_rw_len to nvmet_rw_data_len nvmet: add metadata characteristics for a namespace nvme-rdma: add metadata/T10-PI support nvme-rdma: introduce nvme_rdma_sgl structure ...
2020-05-27bcache: use bio_{start,end}_io_acctChristoph Hellwig1-14/+4
Switch bcache to use the nicer bio accounting helpers, and call the routines where we also sample the start time to give coherent accounting results. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Acked-by: Coly Li <colyli@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-05-27bcache: Convert pr_<level> uses to a more typical styleJoe Perches1-3/+3
Remove the trailing newline from the define of pr_fmt and add newlines to the uses. Miscellanea: o Convert bch_bkey_dump from multiple uses of pr_err to pr_cont as the earlier conversion was inappropriate done causing multiple lines to be emitted where only a single output line was desired o Use vsprintf extension %pV in bch_cache_set_error to avoid multiple line output where only a single line output was desired o Coalesce formats Fixes: 6ae63e3501c4 ("bcache: replace printk() by pr_*() routines") Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Coly Li <colyli@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-04-25bcache: remove a duplicate ->make_request_fn assignmentChristoph Hellwig1-1/+0
The make_request_fn pointer should only be assigned by blk_alloc_queue. Fix a left over manual initialization. Fixes: ff27668ce809 ("bcache: pass the make_request methods to blk_queue_make_request") Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-03-27bcache: pass the make_request methods to blk_queue_make_requestChristoph Hellwig1-5/+2
bcache is the only driver not actually passing its make_request methods to blk_queue_make_request, but instead just sets them up manually a little later. Make bcache follow the common way of setting up make_request based queues. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-02-01bcache: add readahead cache policy options via sysfs interfaceColy Li1-5/+12
In year 2007 high performance SSD was still expensive, in order to save more space for real workload or meta data, the readahead I/Os for non-meta data was bypassed and not cached on SSD. In now days, SSD price drops a lot and people can find larger size SSD with more comfortable price. It is unncessary to alway bypass normal readahead I/Os to save SSD space for now. This patch adds options for readahead data cache policies via sysfs file /sys/block/bcache<N>/readahead_cache_policy, the options are, - "all": cache all readahead data I/Os. - "meta-only": only cache meta data, and bypass other regular I/Os. If users want to make bcache continue to only cache readahead request for metadata and bypass regular data readahead, please set "meta-only" to this sysfs file. By default, bcache will back to cache all read- ahead requests now. Cc: stable@vger.kernel.org Signed-off-by: Coly Li <colyli@suse.de> Acked-by: Eric Wheeler <bcache@linux.ewheeler.net> Cc: Michael Lyle <mlyle@lyle.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-11-14bcache: deleted code comments for dead code in bch_data_insert_keys()Coly Li1-12/+0
In request.c:bch_data_insert_keys(), there is code comment for a piece of dead code. This patch deletes the dead code and its code comment since they are useless in practice. Signed-off-by: Coly Li <colyli@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-04-24bcache: Clean up bch_get_congested()George Spelvin1-7/+8
There are a few nits in this function. They could in theory all be separate patches, but that's probably taking small commits too far. 1) I added a brief comment saying what it does. 2) I like to declare pointer parameters "const" where possible for documentation reasons. 3) It uses bitmap_weight(&rand, BITS_PER_LONG) to compute the Hamming weight of a 32-bit random number (giving a random integer with mean 16 and variance 8). Passing by reference in a 64-bit variable is silly; just use hweight32(). 4) Its helper function fract_exp_two is unnecessarily tangled. Gcc can optimize the multiply by (1 << x) to a shift, but it can be written in a much more straightforward way at the cost of one more bit of internal precision. Some analysis reveals that this bit is always available. This shrinks the object code for fract_exp_two(x, 6) from 23 bytes: 0000000000000000 <foo1>: 0: 89 f9 mov %edi,%ecx 2: c1 e9 06 shr $0x6,%ecx 5: b8 01 00 00 00 mov $0x1,%eax a: d3 e0 shl %cl,%eax c: 83 e7 3f and $0x3f,%edi f: d3 e7 shl %cl,%edi 11: c1 ef 06 shr $0x6,%edi 14: 01 f8 add %edi,%eax 16: c3 retq To 19: 0000000000000017 <foo2>: 17: 89 f8 mov %edi,%eax 19: 83 e0 3f and $0x3f,%eax 1c: 83 c0 40 add $0x40,%eax 1f: 89 f9 mov %edi,%ecx 21: c1 e9 06 shr $0x6,%ecx 24: d3 e0 shl %cl,%eax 26: c1 e8 06 shr $0x6,%eax 29: c3 retq (Verified with 0 <= frac_bits <= 8, 0 <= x < 16<<frac_bits; both versions produce the same output.) 5) And finally, the call to bch_get_congested() in check_should_bypass() is separated from the use of the value by multiple tests which could moot the need to compute it. Move the computation down to where it's needed. This also saves a local register to hold the computed value. Signed-off-by: George Spelvin <lkml@sdf.org> Signed-off-by: Coly Li <colyli@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-04-24bcache: fix crashes stopping bcache device before read miss doneGuoju Fang1-5/+21
The bio from upper layer is considered completed when bio_complete() returns. In most scenarios bio_complete() is called in search_free(), but when read miss happens, the bio_compete() is called when backing device reading completed, while the struct search is still in use until cache inserting finished. If someone stops the bcache device just then, the device may be closed and released, but after cache inserting finished the struct search will access a freed struct cached_dev. This patch add the reference of bcache device before bio_complete() when read miss happens, and put it after the search is not used. Signed-off-by: Guoju Fang <fangguoju@gmail.com> Signed-off-by: Coly Li <colyli@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-02-09bcache: use (REQ_META|REQ_PRIO) to indicate bio for metadataColy Li1-3/+4
In 'commit 752f66a75aba ("bcache: use REQ_PRIO to indicate bio for metadata")' REQ_META is replaced by REQ_PRIO to indicate metadata bio. This assumption is not always correct, e.g. XFS uses REQ_META to mark metadata bio other than REQ_PRIO. This is why Nix noticed that bcache does not cache metadata for XFS after the above commit. Thanks to Dave Chinner, he explains the difference between REQ_META and REQ_PRIO from view of file system developer. Here I quote part of his explanation from mailing list, REQ_META is used for metadata. REQ_PRIO is used to communicate to the lower layers that the submitter considers this IO to be more important that non REQ_PRIO IO and so dispatch should be expedited. IOWs, if the filesystem considers metadata IO to be more important that user data IO, then it will use REQ_PRIO | REQ_META rather than just REQ_META. Then it seems bios with REQ_META or REQ_PRIO should both be cached for performance optimation, because they are all probably low I/O latency demand by upper layer (e.g. file system). So in this patch, when we want to decide whether to bypass the cache, REQ_META and REQ_PRIO are both checked. Then both metadata and high priority I/O requests will be handled properly. Reported-by: Nix <nix@esperi.org.uk> Signed-off-by: Coly Li <colyli@suse.de> Reviewed-by: Andre Noll <maan@tuebingen.mpg.de> Tested-by: Nix <nix@esperi.org.uk> Cc: stable@vger.kernel.org Cc: Dave Chinner <david@fromorbit.com> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-13bcache: update comment for bch_data_insertShenghui Wang1-3/+3
commit 220bb38c21b8 ("bcache: Break up struct search") introduced changes to struct search and s->iop. bypass/bio are fields of struct data_insert_op now. Update the comment. Signed-off-by: Shenghui Wang <shhuiw@foxmail.com> Signed-off-by: Coly Li <colyli@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-10-08bcache: fix ioctl in flash deviceTang Junhui1-0/+3
When doing ioctl in flash device, it will call ioctl_dev() in super.c, then we should not to get cached device since flash only device has no backend device. This patch just move the jugement dc->io_disable to cached_dev_ioctl() to make ioctl in flash device correctly. Fixes: 0f0709e6bfc3c ("bcache: stop bcache device when backing device is offline") Signed-off-by: Tang Junhui <tang.junhui.linux@gmail.com> Cc: stable@vger.kernel.org Signed-off-by: Coly Li <colyli@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-10-08bcache: use REQ_PRIO to indicate bio for metadataColy Li1-2/+2
In cached_dev_cache_miss() and check_should_bypass(), REQ_META is used to check whether a bio is for metadata request. REQ_META is used for blktrace, the correct REQ_ flag should be REQ_PRIO. This flag means the bio should be prior to other bio, and frequently be used to indicate metadata io in file system code. This patch replaces REQ_META with correct flag REQ_PRIO. CC Adam Manzanares because he explains to me what REQ_PRIO is for. Signed-off-by: Coly Li <colyli@suse.de> Cc: Adam Manzanares <adam.manzanares@wdc.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-10-08bcache: trace missed reading by cache_missedTang Junhui1-1/+1
Missed reading IOs are identified by s->cache_missed, not the s->cache_miss, so in trace_bcache_read() using trace_bcache_read to identify whether the IO is missed or not. Signed-off-by: Tang Junhui <tang.junhui.linux@gmail.com> Cc: stable@vger.kernel.org Signed-off-by: Coly Li <colyli@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>