linux.git/drivers/md/dm-raid.c, branch v5.10

Revert "dm raid: remove unnecessary discard limits for raid10"

2020-12-10T04:43:48+00:00

This reverts commit f0e90b6c663a7e3b4736cb318c6c7c589f152c28.

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 
Cc: Mike Snitzer 
Acked-by: Mike Snitzer 
Signed-off-by: Song Liu

dm raid: remove unnecessary discard limits for raid10

2020-09-29T20:33:10+00:00

Commit bcc90d280465e ("md/raid10: improve raid10 discard request")
removes raid10's inability to properly handle large discards.  So
eliminate associated constraint from dm-raid's raid10 support.

Signed-off-by: Mike Snitzer

dm raid: fix discard limits for raid1 and raid10

2020-09-29T20:33:09+00:00

Block core warned that discard_granularity was 0 for dm-raid with
personality of raid1.  Reason is that raid_io_hints() was incorrectly
special-casing raid1 rather than raid0.

But since commit 29efc390b9462 ("md/md0: optimize raid0 discard
handling") even raid0 properly handles large discards.

Fix raid_io_hints() by removing discard limits settings for raid1.
Also, fix limits for raid10 by properly stacking underlying limits as
done in blk_stack_limits().

Depends-on: 29efc390b9462 ("md/md0: optimize raid0 discard handling")
Fixes: 61697a6abd24a ("dm: eliminate 'split_discard_bios' flag from DM target interface")
Cc: stable@vger.kernel.org
Reported-by: Zdenek Kabelac 
Reported-by: Mikulas Patocka 
Signed-off-by: Mike Snitzer

block: add a new revalidate_disk_size helper

2020-09-02T14:00:07+00:00

revalidate_disk is a relative awkward helper for driver use, as it first
calls an optional driver method and then updates the block device size,
while most callers either don't need the method call at all, or want to
keep state between the caller and the called method.

Add a revalidate_disk_size helper that just performs the update of the
block device size from the gendisk one, and switch all drivers that do
not implement ->revalidate_disk to use the new helper instead of
revalidate_disk()

Signed-off-by: Christoph Hellwig 
Reviewed-by: Josef Bacik 
Reviewed-by: Johannes Thumshirn 
Acked-by: Song Liu 
Signed-off-by: Jens Axboe

Merge tag 'for-5.9/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

2020-08-07T20:08:09+00:00

Pull device mapper updates from Mike Snitzer:

- DM multipath locking fixes around m->flags tests and improvements to
bio-based code so that it follows patterns established by
request-based code.

- Request-based DM core improvement to eliminate unnecessary call to
blk_mq_queue_stopped().

- Add "panic_on_corruption" error handling mode to DM verity target.

- DM bufio fix to to perform buffer cleanup from a workqueue rather
than wait for IO in reclaim context from shrinker.

- DM crypt improvement to optionally avoid async processing via
workqueues for reads and/or writes -- via "no_read_workqueue" and
"no_write_workqueue" features. This more direct IO processing
improves latency and throughput with faster storage. Avoiding
workqueue IO submission for writes (DM_CRYPT_NO_WRITE_WORKQUEUE) is a
requirement for adding zoned block device support to DM crypt.

- Add zoned block device support to DM crypt. Makes use of
DM_CRYPT_NO_WRITE_WORKQUEUE and a new optional feature
(DM_CRYPT_WRITE_INLINE) that allows write completion to wait for
encryption to complete. This allows write ordering to be preserved,
which is needed for zoned block devices.

- Fix DM ebs target's check for REQ_OP_FLUSH.

- Fix DM core's report zones support to not report more zones than were
requested.

- A few small compiler warning fixes.

- DM dust improvements to return output directly to the user rather
than require they scrape the system log for output.

* tag 'for-5.9/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
dm: don't call report zones for more than the user requested
dm ebs: Fix incorrect checking for REQ_OP_FLUSH
dm init: Set file local variable static
dm ioctl: Fix compilation warning
dm raid: Remove empty if statement
dm verity: Fix compilation warning
dm crypt: Enable zoned block device support
dm crypt: add flags to optionally bypass kcryptd workqueues
dm bufio: do buffer cleanup from a workqueue
dm rq: don't call blk_mq_queue_stopped() in dm_stop_queue()
dm dust: add interface to list all badblocks
dm dust: report some message results directly back to user
dm verity: add "panic_on_corruption" error handling mode
dm mpath: use double checked locking in fast path
dm mpath: rename current_pgpath to pgpath in multipath_prepare_ioctl
dm mpath: rework __map_bio()
dm mpath: factor out multipath_queue_bio
dm mpath: push locking down to must_push_back_rq()
dm mpath: take m->lock spinlock when testing QUEUE_IF_NO_PATH
dm mpath: changes from initial m->flags locking audit

dm raid: Remove empty if statement

2020-08-04T19:48:48+00:00

In super_init_validation(), remove a body-less if statement testing only
variables to avoid a compilation warning when compiling with W=1.

Signed-off-by: Damien Le Moal 
Signed-off-by: Mike Snitzer

writeback: remove bdi->congested_fn

2020-07-08T23:20:46+00:00

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 
Acked-by: Song Liu 
Acked-by: David Sterba 
[axboe: fixup unused variables in bcache/request.c]
Signed-off-by: Jens Axboe

dm: replace zero-length array with flexible-array

2020-05-20T21:09:44+00:00

The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:

struct foo {
        int stuff;
        struct boo array[];
};

By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.

Also, notice that, dynamic memory allocations won't be affected by
this change:

"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]

sizeof(flexible-array-member) triggers a warning because flexible array
members have incomplete type[1]. There are some instances of code in
which the sizeof operator is being incorrectly/erroneously applied to
zero-length arrays and the result is zero. Such instances may be hiding
some bugs. So, this work (flexible-array member conversions) will also
help to get completely rid of those sorts of issues.

This issue was found with the help of Coccinelle.

[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva 
Signed-off-by: Mike Snitzer

dm raid: table line rebuild status fixes

2020-01-07T16:43:37+00:00

raid_status() wasn't emitting rebuild flags on the table line properly
because the rdev number was not yet set properly; index raid component
devices array directly to solve.

Also fix wrong argument count on emitted table line caused by 1 too
many rebuild/write_mostly argument and consider any journal_(dev|mode)
pairs.

Link: https://bugzilla.redhat.com/1782045
Signed-off-by: Heinz Mauelshagen 
Signed-off-by: Mike Snitzer

dm raid: Remove unnecessary negation of a shift in raid10_format_to_md_layout

2019-11-07T16:59:38+00:00

When building with Clang + -Wtautological-constant-compare:

 drivers/md/dm-raid.c:619:8: warning: converting the result of '<<' to a
 boolean always evaluates to true [-Wtautological-constant-compare]
                 r = !RAID10_OFFSET;
                      ^
 drivers/md/dm-raid.c:517:28: note: expanded from macro 'RAID10_OFFSET'
 #define RAID10_OFFSET                   (1 << 16) /* stripes with data
 copies area adjacent on devices */
                                           ^
 1 warning generated.

Negating a non-zero number will always make it zero, which is the
default value of r in this function so this statement is unnecessary;
remove it so that clang no longer warns.

Link: https://github.com/ClangBuiltLinux/linux/issues/753
Signed-off-by: Nathan Chancellor 
Acked-by: Heinz Mauelshagen 
Signed-off-by: Mike Snitzer