linux-stable.git/block/bio.c, branch v5.12.2 Linux kernel stable tree block: only update parent bi_status when bio fail 2021-04-01T01:18:04+00:00 Yufen Yu yuyufen@huawei.com 2021-03-31T11:53:59+00:00 3edf5346e4f2ce2fa0c94651a90a8dda169565ee For multiple split bios, if one of the bio is fail, the whole should return error to application. But we found there is a race between bio_integrity_verify_fn and bio complete, which return io success to application after one of the bio fail. The race as following: split bio(READ) kworker nvme_complete_rq blk_update_request //split error=0 bio_endio bio_integrity_endio queue_work(kintegrityd_wq, &bip->bip_work); bio_integrity_verify_fn bio_endio //split bio __bio_chain_endio if (!parent->bi_status) <interrupt entry> nvme_irq blk_update_request //parent error=7 req_bio_endio bio->bi_status = 7 //parent bio <interrupt exit> parent->bi_status = 0 parent->bi_end_io() // return bi_status=0 The bio has been split as two: split and parent. When split bio completed, it depends on kworker to do endio, while bio_integrity_verify_fn have been interrupted by parent bio complete irq handler. Then, parent bio->bi_status which have been set in irq handler will overwrite by kworker. In fact, even without the above race, we also need to conside the concurrency beteen mulitple split bio complete and update the same parent bi_status. Normally, multiple split bios will be issued to the same hctx and complete from the same irq vector. But if we have updated queue map between multiple split bios, these bios may complete on different hw queue and different irq vector. Then the concurrency update parent bi_status may cause the final status error. Suggested-by: Keith Busch <kbusch@kernel.org> Signed-off-by: Yufen Yu <yuyufen@huawei.com> Reviewed-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20210331115359.1125679-1-yuyufen@huawei.com Signed-off-by: Jens Axboe <axboe@kernel.dk> 
For multiple split bios, if one of the bio is fail, the whole
should return error to application. But we found there is a race
between bio_integrity_verify_fn and bio complete, which return
io success to application after one of the bio fail. The race as
following:

split bio(READ)          kworker

nvme_complete_rq
blk_update_request //split error=0
  bio_endio
    bio_integrity_endio
      queue_work(kintegrityd_wq, &bip->bip_work);

                         bio_integrity_verify_fn
                         bio_endio //split bio
                          __bio_chain_endio
                             if (!parent->bi_status)

                               <interrupt entry>
                               nvme_irq
                                 blk_update_request //parent error=7
                                 req_bio_endio
                                    bio->bi_status = 7 //parent bio
                               <interrupt exit>

                               parent->bi_status = 0
                        parent->bi_end_io() // return bi_status=0

The bio has been split as two: split and parent. When split
bio completed, it depends on kworker to do endio, while
bio_integrity_verify_fn have been interrupted by parent bio
complete irq handler. Then, parent bio->bi_status which have
been set in irq handler will overwrite by kworker.

In fact, even without the above race, we also need to conside
the concurrency beteen mulitple split bio complete and update
the same parent bi_status. Normally, multiple split bios will
be issued to the same hctx and complete from the same irq
vector. But if we have updated queue map between multiple split
bios, these bios may complete on different hw queue and different
irq vector. Then the concurrency update parent bi_status may
cause the final status error.

Suggested-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Yufen Yu <yuyufen@huawei.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20210331115359.1125679-1-yuyufen@huawei.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
block: support zone append bvecs 2021-03-24T17:36:51+00:00 Johannes Thumshirn johannes.thumshirn@wdc.com 2021-03-24T15:47:26+00:00 7de55b7d6f09a2865279d3c41c0fbdbfdb87486a Christoph reported that we'll likely trigger the WARN_ON_ONCE() checking that we're not submitting a bvec with REQ_OP_ZONE_APPEND in bio_iov_iter_get_pages() some time ago using zoned btrfs, but I couldn't reproduce it back then. Now Naohiro was able to trigger the bug as well with xfstests generic/095 on a zoned btrfs. There is nothing that prevents bvec submissions via REQ_OP_ZONE_APPEND if the hardware's zone append limit is met. Reported-by: Naohiro Aota <naohiro.aota@wdc.com> Reported-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/10bd414d9326c90cd69029077db63b363854eee5.1616600835.git.johannes.thumshirn@wdc.com Signed-off-by: Jens Axboe <axboe@kernel.dk> 
Christoph reported that we'll likely trigger the WARN_ON_ONCE() checking
that we're not submitting a bvec with REQ_OP_ZONE_APPEND in
bio_iov_iter_get_pages() some time ago using zoned btrfs, but I couldn't
reproduce it back then.

Now Naohiro was able to trigger the bug as well with xfstests generic/095
on a zoned btrfs.

There is nothing that prevents bvec submissions via REQ_OP_ZONE_APPEND if
the hardware's zone append limit is met.

Reported-by: Naohiro Aota <naohiro.aota@wdc.com>
Reported-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/10bd414d9326c90cd69029077db63b363854eee5.1616600835.git.johannes.thumshirn@wdc.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
block: rename BIO_MAX_PAGES to BIO_MAX_VECS 2021-03-11T14:47:48+00:00 Christoph Hellwig hch@lst.de 2021-03-11T11:01:37+00:00 a8affc03a9b375e19bc81573de0c9108317d78c7 Ever since the addition of multipage bio_vecs BIO_MAX_PAGES has been horribly confusingly misnamed. Rename it to BIO_MAX_VECS to stop confusing users of the bio API. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Link: https://lore.kernel.org/r/20210311110137.1132391-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk> 
Ever since the addition of multipage bio_vecs BIO_MAX_PAGES has been
horribly confusingly misnamed.  Rename it to BIO_MAX_VECS to stop
confusing users of the bio API.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20210311110137.1132391-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Merge tag 'for-5.12/block-2021-02-17' of git://git.kernel.dk/linux-block 2021-02-21T19:02:48+00:00 Linus Torvalds torvalds@linux-foundation.org 2021-02-21T19:02:48+00:00 582cd91f69de8e44857cb610ebca661dac8656b7 Pull core block updates from Jens Axboe: "Another nice round of removing more code than what is added, mostly due to Christoph's relentless pursuit of tech debt removal/cleanups. This pull request contains: - Two series of BFQ improvements (Paolo, Jan, Jia) - Block iov_iter improvements (Pavel) - bsg error path fix (Pan) - blk-mq scheduler improvements (Jan) - -EBUSY discard fix (Jan) - bvec allocation improvements (Ming, Christoph) - bio allocation and init improvements (Christoph) - Store bdev pointer in bio instead of gendisk + partno (Christoph) - Block trace point cleanups (Christoph) - hard read-only vs read-only split (Christoph) - Block based swap cleanups (Christoph) - Zoned write granularity support (Damien) - Various fixes/tweaks (Chunguang, Guoqing, Lei, Lukas, Huhai)" * tag 'for-5.12/block-2021-02-17' of git://git.kernel.dk/linux-block: (104 commits) mm: simplify swapdev_block sd_zbc: clear zone resources for non-zoned case block: introduce blk_queue_clear_zone_settings() zonefs: use zone write granularity as block size block: introduce zone_write_granularity limit block: use blk_queue_set_zoned in add_partition() nullb: use blk_queue_set_zoned() to setup zoned devices nvme: cleanup zone information initialization block: document zone_append_max_bytes attribute block: use bi_max_vecs to find the bvec pool md/raid10: remove dead code in reshape_request block: mark the bio as cloned in bio_iov_bvec_set block: set BIO_NO_PAGE_REF in bio_iov_bvec_set block: remove a layer of indentation in bio_iov_iter_get_pages block: turn the nr_iovecs argument to bio_alloc* into an unsigned short block: remove the 1 and 4 vec bvec_slabs entries block: streamline bvec_alloc block: factor out a bvec_alloc_gfp helper block: move struct biovec_slab to bio.c block: reuse BIO_INLINE_VECS for integrity bvecs ... 
Pull core block updates from Jens Axboe:
 "Another nice round of removing more code than what is added, mostly
  due to Christoph's relentless pursuit of tech debt removal/cleanups.
  This pull request contains:

   - Two series of BFQ improvements (Paolo, Jan, Jia)

   - Block iov_iter improvements (Pavel)

   - bsg error path fix (Pan)

   - blk-mq scheduler improvements (Jan)

   - -EBUSY discard fix (Jan)

   - bvec allocation improvements (Ming, Christoph)

   - bio allocation and init improvements (Christoph)

   - Store bdev pointer in bio instead of gendisk + partno (Christoph)

   - Block trace point cleanups (Christoph)

   - hard read-only vs read-only split (Christoph)

   - Block based swap cleanups (Christoph)

   - Zoned write granularity support (Damien)

   - Various fixes/tweaks (Chunguang, Guoqing, Lei, Lukas, Huhai)"

* tag 'for-5.12/block-2021-02-17' of git://git.kernel.dk/linux-block: (104 commits)
  mm: simplify swapdev_block
  sd_zbc: clear zone resources for non-zoned case
  block: introduce blk_queue_clear_zone_settings()
  zonefs: use zone write granularity as block size
  block: introduce zone_write_granularity limit
  block: use blk_queue_set_zoned in add_partition()
  nullb: use blk_queue_set_zoned() to setup zoned devices
  nvme: cleanup zone information initialization
  block: document zone_append_max_bytes attribute
  block: use bi_max_vecs to find the bvec pool
  md/raid10: remove dead code in reshape_request
  block: mark the bio as cloned in bio_iov_bvec_set
  block: set BIO_NO_PAGE_REF in bio_iov_bvec_set
  block: remove a layer of indentation in bio_iov_iter_get_pages
  block: turn the nr_iovecs argument to bio_alloc* into an unsigned short
  block: remove the 1 and 4 vec bvec_slabs entries
  block: streamline bvec_alloc
  block: factor out a bvec_alloc_gfp helper
  block: move struct biovec_slab to bio.c
  block: reuse BIO_INLINE_VECS for integrity bvecs
  ...
block: add bio_add_zone_append_page 2021-02-08T23:52:19+00:00 Johannes Thumshirn johannes.thumshirn@wdc.com 2021-02-04T10:21:40+00:00 ae29333fa644679b96d88c9dd3afbef25cbac0f6 Add bio_add_zone_append_page(), a wrapper around bio_add_hw_page() which is intended to be used by file systems that directly add pages to a bio instead of using bio_iov_iter_get_pages(). Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> Acked-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: David Sterba <dsterba@suse.com> 
Add bio_add_zone_append_page(), a wrapper around bio_add_hw_page() which
is intended to be used by file systems that directly add pages to a bio
instead of using bio_iov_iter_get_pages().

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Acked-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
block: use bi_max_vecs to find the bvec pool 2021-02-08T15:33:16+00:00 Christoph Hellwig hch@lst.de 2021-02-02T17:19:29+00:00 7a800a20ae6329e803c5c646b20811a6ae9ca136 Instead of encoding of the bvec pool using magic bio flags, just use a helper to find the pool based on the max_vecs value. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk> 
Instead of encoding of the bvec pool using magic bio flags, just use
a helper to find the pool based on the max_vecs value.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
block: mark the bio as cloned in bio_iov_bvec_set 2021-02-08T15:33:16+00:00 Christoph Hellwig hch@lst.de 2021-02-02T17:19:27+00:00 977be01273844626ddeef4a464b42b99418d76e6 bio_iov_bvec_set clones the bio_vecs from the iter, and thus should be treated like a cloned bio in every respect. That also includes not touching bi_max_vecs as that is a property of the bio allocation and not its current payload. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk> 
bio_iov_bvec_set clones the bio_vecs from the iter, and thus should be
treated like a cloned bio in every respect.  That also includes not
touching bi_max_vecs as that is a property of the bio allocation and not
its current payload.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
block: set BIO_NO_PAGE_REF in bio_iov_bvec_set 2021-02-08T15:33:16+00:00 Christoph Hellwig hch@lst.de 2021-02-02T17:19:26+00:00 ed97ce5e1daf26d456760443fc89dc14d2b677e5 bio_iov_bvec_set assigns the foreign bvec, so setting the NO_PAGE_REF directly there seems like the best fit. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk> 
bio_iov_bvec_set assigns the foreign bvec, so setting the NO_PAGE_REF
directly there seems like the best fit.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
block: remove a layer of indentation in bio_iov_iter_get_pages 2021-02-08T15:33:16+00:00 Christoph Hellwig hch@lst.de 2021-02-02T17:19:25+00:00 86004515ed80c01d59ab54b5d048164750af3c4b Remove a pointless layer of indentation after a return statement. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk> 
Remove a pointless layer of indentation after a return statement.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
block: turn the nr_iovecs argument to bio_alloc* into an unsigned short 2021-02-08T15:33:16+00:00 Christoph Hellwig hch@lst.de 2021-02-02T17:19:24+00:00 0f2e6ab851ae146c468bc5151c302c6e2473f70a The bi_max_vecs and bi_vcnt fields are defined as unsigned short, so don't allow passing larger values in. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk> 
The bi_max_vecs and bi_vcnt fields are defined as unsigned short, so
don't allow passing larger values in.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>