linux-stable.git/drivers/md/raid10.c, branch v5.10

Revert "md/raid10: extend r10bio devs to raid disks"

2020-12-10T04:46:01+00:00

This reverts commit 8650a889017cb1f6ea6813ccf83a2e9f6fa49dd3.

Matthew Ruffell reported data corruption in raid10 due to the changes
in discard handling [1]. Revert these changes before we find a proper fix.

[1] https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1907262/
Cc: Matthew Ruffell 
Cc: Xiao Ni 
Signed-off-by: Song Liu

Revert "md/raid10: pull codes that wait for blocked dev into one function"

2020-12-10T04:46:01+00:00

This reverts commit f046f5d0d79cdb968f219ce249e497fd1accf484.

Matthew Ruffell reported data corruption in raid10 due to the changes
in discard handling [1]. Revert these changes before we find a proper fix.

[1] https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1907262/
Cc: Matthew Ruffell 
Cc: Xiao Ni 
Signed-off-by: Song Liu

Revert "md/raid10: improve raid10 discard request"

2020-12-10T04:46:00+00:00

This reverts commit bcc90d280465ebd51ab8688be86e1f00c62dccf9.

Matthew Ruffell reported data corruption in raid10 due to the changes
in discard handling [1]. Revert these changes before we find a proper fix.

[1] https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1907262/
Cc: Matthew Ruffell 
Cc: Xiao Ni 
Signed-off-by: Song Liu

Revert "md/raid10: improve discard request for far layout"

2020-12-10T04:46:00+00:00

This reverts commit d3ee2d8415a6256c1c41e1be36e80e640c3e6359.

Matthew Ruffell reported data corruption in raid10 due to the changes
in discard handling [1]. Revert these changes before we find a proper fix.

[1] https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1907262/
Cc: Matthew Ruffell 
Cc: Xiao Ni 
Signed-off-by: Song Liu

md/raid10: improve discard request for far layout

2020-09-24T23:44:45+00:00

For far layout, the discard region is not continuous on disks. So it needs
far copies r10bio to cover all regions. It needs a way to know all r10bios
have finish or not. Similar with raid10_sync_request, only the first r10bio
master_bio records the discard bio. Other r10bios master_bio record the
first r10bio. The first r10bio can finish after other r10bios finish and
then return the discard bio.

Signed-off-by: Xiao Ni 
Signed-off-by: Song Liu

md/raid10: improve raid10 discard request

2020-09-24T23:44:45+00:00

Now the discard request is split by chunk size. So it takes a long time
to finish mkfs on disks which support discard function. This patch improve
handling raid10 discard request. It uses the similar way with patch
29efc390b (md/md0: optimize raid0 discard handling).

But it's a little complex than raid0. Because raid10 has different layout.
If raid10 is offset layout and the discard request is smaller than stripe
size. There are some holes when we submit discard bio to underlayer disks.

For example: five disks (disk1 - disk5)
D01 D02 D03 D04 D05
D05 D01 D02 D03 D04
D06 D07 D08 D09 D10
D10 D06 D07 D08 D09
The discard bio just wants to discard from D03 to D10. For disk3, there is
a hole between D03 and D08. For disk4, there is a hole between D04 and D09.
D03 is a chunk, raid10_write_request can handle one chunk perfectly. So
the part that is not aligned with stripe size is still handled by
raid10_write_request.

If reshape is running when discard bio comes and the discard bio spans the
reshape position, raid10_write_request is responsible to handle this
discard bio.

I did a test with this patch set.
Without patch:
time mkfs.xfs /dev/md0
real4m39.775s
user0m0.000s
sys0m0.298s

With patch:
time mkfs.xfs /dev/md0
real0m0.105s
user0m0.000s
sys0m0.007s

nvme3n1           259:1    0   477G  0 disk
└─nvme3n1p1       259:10   0    50G  0 part
nvme4n1           259:2    0   477G  0 disk
└─nvme4n1p1       259:11   0    50G  0 part
nvme5n1           259:6    0   477G  0 disk
└─nvme5n1p1       259:12   0    50G  0 part
nvme2n1           259:9    0   477G  0 disk
└─nvme2n1p1       259:15   0    50G  0 part
nvme0n1           259:13   0   477G  0 disk
└─nvme0n1p1       259:14   0    50G  0 part

Reviewed-by: Coly Li 
Reviewed-by: Guoqing Jiang 
Signed-off-by: Xiao Ni 
Signed-off-by: Song Liu

md/raid10: pull codes that wait for blocked dev into one function

2020-09-24T23:44:45+00:00

The following patch will reuse these logics, so pull the same codes into
one function.

Signed-off-by: Xiao Ni 
Signed-off-by: Song Liu

md/raid10: extend r10bio devs to raid disks

2020-09-24T23:44:45+00:00

Now it allocs r10bio->devs[conf->copies]. Discard bio needs to submit
to all member disks and it needs to use r10bio. So extend to
r10bio->devs[geo.raid_disks].

Reviewed-by: Coly Li 
Signed-off-by: Xiao Ni 
Signed-off-by: Song Liu

md: Simplify code with existing definition RESYNC_SECTORS in raid10.c

2020-09-24T23:44:45+00:00

#define RESYNC_SECTORS (RESYNC_BLOCK_SIZE >> 9)

"RESYNC_BLOCK_SIZE/512" is equal to "RESYNC_BLOCK_SIZE >> 9", replace it
with RESYNC_SECTORS.

Signed-off-by: Zhen Lei 
Signed-off-by: Song Liu

block: lift setting the readahead size into the block layer

2020-09-24T19:43:39+00:00

Drivers shouldn't really mess with the readahead size, as that is a VM
concept.  Instead set it based on the optimal I/O size by lifting the
algorithm from the md driver when registering the disk.  Also set
bdi->io_pages there as well by applying the same scheme based on
max_sectors.  To ensure the limits work well for stacking drivers a
new helper is added to update the readahead limits from the block
limits, which is also called from disk_stack_limits.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Johannes Thumshirn 
Reviewed-by: Jan Kara 
Reviewed-by: Mike Snitzer 
Reviewed-by: Martin K. Petersen 
Acked-by: Coly Li 
Signed-off-by: Jens Axboe