kernel/linux.git/block/bio.c, branch v5.7.4

block: move bio_map_* to blk-map.c

2020-03-27T18:04:34+00:00

The bio_map_* helpers are just the low-level helpers for the blk_rq_map_* APIs. Move them together for better logical grouping, as no there isn't much overlap with other code in bio.c. Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe

block: move guard_bio_eod to bio.c

2020-03-25T15:50:08+00:00

This is bio layer functionality and not related to buffer heads. Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe

block/diskstats: replace time_in_queue with sum of request times

2020-03-25T14:49:12+00:00

Column "time_in_queue" in diskstats is supposed to show total waiting time of all requests. I.e. value should be equal to the sum of times from other columns. But this is not true, because column "time_in_queue" is counted separately in jiffies rather than in nanoseconds as other times. This patch removes redundant counter for "time_in_queue" and shows total time of read, write, discard and flush requests. Signed-off-by: Konstantin Khlebnikov Signed-off-by: Jens Axboe

block/diskstats: more accurate approximation of io_ticks for slow disks

2020-03-25T14:49:08+00:00

Currently io_ticks is approximated by adding one at each start and end of requests if jiffies counter has changed. This works perfectly for requests shorter than a jiffy or if one of requests starts/ends at each jiffy. If disk executes just one request at a time and they are longer than two jiffies then only first and last jiffies will be accounted. Fix is simple: at the end of request add up into io_ticks jiffies passed since last update rather than just one jiffy. Example: common HDD executes random read 4k requests around 12ms. fio --name=test --filename=/dev/sdb --rw=randread --direct=1 --runtime=30 & iostat -x 10 sdb Note changes of iostat's "%util" 8,43% -> 99,99% before/after patch: Before: Device: rrqm/s wrqm/s r/s w/s rkB/s wkB/s avgrq-sz avgqu-sz await r_await w_await svctm %util sdb 0,00 0,00 82,60 0,00 330,40 0,00 8,00 0,96 12,09 12,09 0,00 1,02 8,43 After: Device: rrqm/s wrqm/s r/s w/s rkB/s wkB/s avgrq-sz avgqu-sz await r_await w_await svctm %util sdb 0,00 0,00 82,50 0,00 330,00 0,00 8,00 1,00 12,10 12,10 0,00 12,12 99,99 Now io_ticks does not loose time between start and end of requests, but for queue-depth > 1 some I/O time between adjacent starts might be lost. For load estimation "%util" is not as useful as average queue length, but it clearly shows how often disk queue is completely empty. Fixes: 5b18b5a73760 ("block: delete part_round_stats and switch to less precise counting") Signed-off-by: Konstantin Khlebnikov Reviewed-by: Ming Lei Signed-off-by: Jens Axboe

block: move disk_name and related helpers out of partition-generic.c

2020-03-24T13:57:07+00:00

Thes functions aren't really related to partition support, so move them to a more suitable place. Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe

block: Prevent hung_check firing during long sync IO

2020-03-18T14:48:03+00:00

submit_bio_wait() can be called from ioctl(BLKSECDISCARD), which may take long time to complete, as Salman mentioned, 4K BLKSECDISCARD takes up to 100 second on some devices. Also any block I/O operation that occurs after the BLKSECDISCARD is submitted will also potentially be affected by the hung task timeouts. Another report is that task hang can be observed when running mkfs over raid10 which takes a small max discard sectors limit because of chunk size. So prevent hung_check from firing by taking same approach used in blk_execute_rq(), and the wake-up interval is set as half the hung_check timer period, which keeps overhead low enough. Cc: Salman Qazi Cc: Jesse Barnes Cc: Bart Van Assche Link: https://lkml.org/lkml/2020/2/12/1193 Reported-by: Salman Qazi Reviewed-by: Jesse Barnes Reviewed-by: Salman Qazi Signed-off-by: Ming Lei Signed-off-by: Jens Axboe

fs: move guard_bio_eod() after bio_set_op_attrs

2020-01-09T15:16:12+00:00

Commit 85a8ce62c2ea ("block: add bio_truncate to fix guard_bio_eod") adds bio_truncate() for handling bio EOD. However, bio_truncate() doesn't use the passed 'op' parameter from guard_bio_eod's callers. So bio_trunacate() may retrieve wrong 'op', and zering pages may not be done for READ bio. Fixes this issue by moving guard_bio_eod() after bio_set_op_attrs() in submit_bh_wbc() so that bio_truncate() can always retrieve correct op info. Meantime remove the 'op' parameter from guard_bio_eod() because it isn't used any more. Cc: Carlos Maiolino Cc: linux-fsdevel@vger.kernel.org Fixes: 85a8ce62c2ea ("block: add bio_truncate to fix guard_bio_eod") Signed-off-by: Ming Lei Fold in kerneldoc and bio_op() change. Signed-off-by: Jens Axboe

block: add bio_truncate to fix guard_bio_eod

2019-12-28T16:44:56+00:00

Some filesystem, such as vfat, may send bio which crosses device boundary, and the worse thing is that the IO request starting within device boundaries can contain more than one segment past EOD. Commit dce30ca9e3b6 ("fs: fix guard_bio_eod to check for real EOD errors") tries to fix this issue by returning -EIO for this situation. However, this way lets fs user code lose chance to handle -EIO, then sync_inodes_sb() may hang for ever. Also the current truncating on last segment is dangerous by updating the last bvec, given bvec table becomes not immutable any more, and fs bio users may not retrieve the truncated pages via bio_for_each_segment_all() in its .end_io callback. Fixes this issue by supporting multi-segment truncating. And the approach is simpler: - just update bio size since block layer can make correct bvec with the updated bio size. Then bvec table becomes really immutable. - zero all truncated segments for read bio Cc: Carlos Maiolino Cc: linux-fsdevel@vger.kernel.org Fixed-by: dce30ca9e3b6 ("fs: fix guard_bio_eod to check for real EOD errors") Reported-by: syzbot+2b9e54155c8c25d8d165@syzkaller.appspotmail.com Signed-off-by: Ming Lei Signed-off-by: Jens Axboe

block: fix "check bi_size overflow before merge"

2019-12-10T05:04:35+00:00

This partially reverts commit e3a5d8e386c3fb973fa75f2403622a8f3640ec06. Commit e3a5d8e386c3 ("check bi_size overflow before merge") adds a bio_full check to __bio_try_merge_page. This will cause __bio_try_merge_page to fail when the last bi_io_vec has been reached. Instead, what we want here is only the bi_size overflow check. Fixes: e3a5d8e386c3 ("block: check bi_size overflow before merge") Cc: stable@vger.kernel.org # v5.4+ Reviewed-by: Ming Lei Signed-off-by: Andreas Gruenbacher Signed-off-by: Jens Axboe

block: fix memleak of bio integrity data

2019-12-05T18:38:36+00:00

7c20f11680a4 ("bio-integrity: stop abusing bi_end_io") moves bio_integrity_free from bio_uninit() to bio_integrity_verify_fn() and bio_endio(). This way looks wrong because bio may be freed without calling bio_endio(), for example, blk_rq_unprep_clone() is called from dm_mq_queue_rq() when the underlying queue of dm-mpath is busy. So memory leak of bio integrity data is caused by commit 7c20f11680a4. Fixes this issue by re-adding bio_integrity_free() to bio_uninit(). Fixes: 7c20f11680a4 ("bio-integrity: stop abusing bi_end_io") Reviewed-by: Christoph Hellwig Signed-off-by Justin Tee Add commit log, and simplify/fix the original patch wroten by Justin. Signed-off-by: Ming Lei Signed-off-by: Jens Axboe