Files
odroid-linux/include/linux
Mike Snitzer 3ee16db390 dm: fix IO splitting
Commit 882ec4e609 ("dm table: stack 'chunk_sectors' limit to account
for target-specific splitting") caused a couple regressions:
1) Using lcm_not_zero() when stacking chunk_sectors was a bug because
   chunk_sectors must reflect the most limited of all devices in the
   IO stack.
2) DM targets that set max_io_len but that do _not_ provide an
   .iterate_devices method no longer had there IO split properly.

And commit 5091cdec56 ("dm: change max_io_len() to use
blk_max_size_offset()") also caused a regression where DM no longer
supported varied (per target) IO splitting. The implication being the
potential for severely reduced performance for IO stacks that use a DM
target like dm-cache to hide performance limitations of a slower
device (e.g. one that requires 4K IO splitting).

Coming full circle: Fix all these issues by discontinuing stacking
chunk_sectors up using ti->max_io_len in dm_calculate_queue_limits(),
add optional chunk_sectors override argument to blk_max_size_offset()
and update DM's max_io_len() to pass ti->max_io_len to its
blk_max_size_offset() call.

Passing in an optional chunk_sectors override to blk_max_size_offset()
allows for code reuse of block's centralized calculation for max IO
size based on provided offset and split boundary.

Fixes: 882ec4e609 ("dm table: stack 'chunk_sectors' limit to account for target-specific splitting")
Fixes: 5091cdec56 ("dm: change max_io_len() to use blk_max_size_offset()")
Cc: stable@vger.kernel.org
Reported-by: John Dorminy <jdorminy@redhat.com>
Reported-by: Bruce Johnston <bjohnsto@redhat.com>
Reported-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Reviewed-by: John Dorminy <jdorminy@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
2020-12-04 14:53:15 -05:00
..
2019-12-11 09:12:38 +01:00
2019-11-12 11:43:29 -05:00
2020-06-25 22:25:13 -07:00
2020-06-16 14:19:57 +02:00
2020-10-28 13:18:56 +01:00
2020-05-24 20:48:11 +02:00
2020-07-21 08:24:52 -05:00
2020-07-08 10:48:35 -07:00
2020-12-04 14:53:15 -05:00
2020-10-02 14:59:25 -07:00
2020-09-21 15:00:40 -07:00
2020-10-02 15:00:49 -07:00
2020-10-16 17:21:51 +02:00
2020-03-09 11:12:19 +01:00
2019-12-03 11:20:37 +01:00
2020-06-16 19:25:20 +02:00
2020-07-27 14:29:23 -04:00
2020-05-04 11:19:58 -07:00
2020-08-12 20:42:08 +02:00
2020-06-17 00:07:38 +02:00
2020-10-27 16:22:43 +01:00
2020-03-06 11:06:15 +01:00
2020-09-30 22:44:26 +02:00
2020-07-24 17:12:41 -07:00
2020-08-04 21:02:38 -04:00
2020-09-16 08:54:53 -05:00
2020-05-18 10:30:21 +01:00
2020-08-26 12:41:56 +02:00
2020-10-13 18:38:32 -07:00
2019-12-04 19:44:14 -08:00
2020-06-02 15:15:46 +01:00
2019-12-11 09:12:38 +01:00
2020-09-04 09:25:20 -07:00
2020-05-08 18:18:11 +01:00
2020-05-08 00:12:42 +02:00
2020-05-28 10:31:09 +02:00
2020-09-23 18:02:49 -07:00
2020-03-06 11:56:59 +01:00
2020-09-04 12:46:07 +01:00
2020-08-27 16:06:47 -04:00
2019-11-14 19:06:47 -08:00
2020-10-07 14:28:39 -04:00
2020-05-09 13:57:12 +02:00
2020-07-01 10:49:02 +02:00
2020-09-24 19:49:36 -07:00
2020-07-23 17:34:18 +10:00
2020-05-15 13:51:28 -07:00
2020-08-31 12:52:33 -07:00
2020-10-28 11:41:15 -06:00
2020-10-18 09:27:10 -07:00
2020-05-09 13:57:12 +02:00
2020-08-18 17:06:15 +02:00
2020-07-16 23:19:51 +02:00
2020-11-06 10:05:18 -08:00
2020-08-07 11:33:24 -07:00
2020-09-26 22:55:05 -04:00
2020-05-04 09:16:37 -07:00
2020-07-04 09:35:36 -05:00
2020-09-10 14:03:31 -07:00
2020-01-14 12:20:48 +01:00
2020-07-07 11:58:59 -05:00
2020-08-01 11:28:17 +02:00
2020-04-01 12:06:26 -04:00
2020-10-18 09:27:10 -07:00
2020-10-05 13:21:49 +02:00