Commit graph

6829 commits

Author SHA1 Message Date
Qing Wang 1b86db5f4e bcache: replace snprintf in show functions with sysfs_emit
coccicheck complains about the use of snprintf() in sysfs show functions.

Fix the following coccicheck warning:
drivers/md/bcache/sysfs.h:54:12-20: WARNING: use scnprintf or sprintf.

Implement sysfs_print() by sysfs_emit() and remove snprint() since no one
uses it any more.

Suggested-by: Coly Li <colyli@suse.de>
Signed-off-by: Qing Wang <wangqing@vivo.com>
Signed-off-by: Coly Li <colyli@suse.de>
Link: https://lore.kernel.org/r/20211029060930.119923-3-colyli@suse.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-29 06:43:21 -06:00
Coly Li cf2197ca4b bcache: move uapi header bcache.h to bcache code directory
The header file include/uapi/linux/bcache.h is not really a user space
API heaer. This file defines the ondisk format of bcache internal meta
data but no one includes it from user space, bcache-tools has its own
copy of this header with minor modification.

Therefore, this patch moves include/uapi/linux/bcache.h to bcache code
directory as drivers/md/bcache/bcache_ondisk.h.

Suggested-by: Arnd Bergmann <arnd@kernel.org>
Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Coly Li <colyli@suse.de>
Link: https://lore.kernel.org/r/20211029060930.119923-2-colyli@suse.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-29 06:43:21 -06:00
Luis Chamberlain 2961c3bbca bcache: add error handling support for add_disk()
We never checked for errors on add_disk() as this function
returned void. Now that this is fixed, use the shiny new
error handling.

This driver doesn't do any unwinding with blk_cleanup_disk()
even on errors after add_disk() and so we follow that
tradition.

Acked-by: Coly Li <colyli@suse.de>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Link: https://lore.kernel.org/r/20211015233028.2167651-5-mcgrof@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-21 09:00:56 -06:00
Luis Chamberlain e7089f65dd dm: add add_disk() error handling
We never checked for errors on add_disk() as this function
returned void. Now that this is fixed, use the shiny new
error handling.

There are two calls to dm_setup_md_queue() which can fail then,
one on dm_early_create() and we can easily see that the error path
there calls dm_destroy in the error path. The other use case is on
the ioctl table_load case. If that fails userspace needs to call
the DM_DEV_REMOVE_CMD to cleanup the state - similar to any other
failure.

Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Link: https://lore.kernel.org/r/20211015233028.2167651-4-mcgrof@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-21 09:00:56 -06:00
Christoph Hellwig 39fa7a9555 bcache: remove bch_crc64_update
bch_crc64_update is an entirely pointless wrapper around crc64_be.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Coly Li <colyli@suse.de>
Link: https://lore.kernel.org/r/20211020143812.6403-9-colyli@suse.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-20 08:40:54 -06:00
Christoph Hellwig 00387bd21d bcache: use bvec_kmap_local in bch_data_verify
Using local kmaps slightly reduces the chances to stray writes, and
the bvec interface cleans up the code a little bit.

Also switch from page_address to bvec_kmap_local for cbv to be on the
safe side and to avoid pointlessly poking into bvec internals.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Coly Li <colyli@suse.de>
Link: https://lore.kernel.org/r/20211020143812.6403-8-colyli@suse.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-20 08:40:54 -06:00
Christoph Hellwig 0f5cd7815f bcache: remove the backing_dev_name field from struct cached_dev
Just use the %pg format specifier to print the name directly.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Coly Li <colyli@suse.de>
Link: https://lore.kernel.org/r/20211020143812.6403-7-colyli@suse.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-20 08:40:54 -06:00
Christoph Hellwig 7e84c21507 bcache: remove the cache_dev_name field from struct cache
Just use the %pg format specifier to print the name directly.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Coly Li <colyli@suse.de>
Link: https://lore.kernel.org/r/20211020143812.6403-6-colyli@suse.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-20 08:40:54 -06:00
Lin Feng 0259d4498b bcache: move calc_cached_dev_sectors to proper place on backing device detach
Calculation of cache_set's cached sectors is done by travelling
cached_devs list as shown below:

static void calc_cached_dev_sectors(struct cache_set *c)
{
...
        list_for_each_entry(dc, &c->cached_devs, list)
                sectors += bdev_sectors(dc->bdev);

        c->cached_dev_sectors = sectors;
}

But cached_dev won't be unlinked from c->cached_devs list until we call
following list_move(&dc->list, &uncached_devices),
so previous fix in 'commit 46010141da
("bcache: recal cached_dev_sectors on detach")' is wrong, now we move
it to its right place.

Signed-off-by: Lin Feng <linf@wangsu.com>
Signed-off-by: Coly Li <colyli@suse.de>
Link: https://lore.kernel.org/r/20211020143812.6403-5-colyli@suse.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-20 08:40:54 -06:00
Chao Yu d55f7cb2e5 bcache: fix error info in register_bcache()
In register_bcache(), there are several cases we didn't set
correct error info (return value and/or error message):
- if kzalloc() fails, it needs to return ENOMEM and print
"cannot allocate memory";
- if register_cache() fails, it's better to propagate its
return value rather than using default EINVAL.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Coly Li <colyli@suse.de>
Link: https://lore.kernel.org/r/20211020143812.6403-4-colyli@suse.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-20 08:40:54 -06:00
Ding Senjie a307e2abfc md: bcache: Fix spelling of 'acquire'
acqurie -> acquire

Signed-off-by: Ding Senjie <dingsenjie@yulong.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Coly Li <colyli@suse.de>
Link: https://lore.kernel.org/r/20211020143812.6403-2-colyli@suse.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-20 08:40:54 -06:00
Xiao Ni 8b9e2291e3 md: update superblock after changing rdev flags in state_store
When the in memory flag is changed, we need to persist the change in the
rdev superblock flags. This is needed for "writemostly" and "failfast".

Reviewed-by: Li Feng <fengli@smartx.com>
Signed-off-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-18 14:50:35 -06:00
Guoqing Jiang 5467948604 md: remove unused argument from md_new_event
Actually, mddev is not used by md_new_event.

Signed-off-by: Guoqing Jiang <guoqing.jiang@linux.dev>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-18 14:50:33 -06:00
Guoqing Jiang c6efe4341d md/raid5: call roundup_pow_of_two in raid5_run
Let's call roundup_pow_of_two here instead of open code.

Signed-off-by: Guoqing Jiang <guoqing.jiang@linux.dev>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-18 14:50:31 -06:00
Guoqing Jiang 2e94275ed5 md/raid1: use rdev in raid1_write_request directly
We already get rdev from conf->mirrors[i].rdev at the beginning of the
loop, so just use it.

Signed-off-by: Guoqing Jiang <guoqing.jiang@linux.dev>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-18 14:50:28 -06:00
Guoqing Jiang fd3b6975e9 md/raid1: only allocate write behind bio for WriteMostly device
Commit 6607cd319b ("raid1: ensure write
behind bio has less than BIO_MAX_VECS sectors") tried to guarantee the
size of behind bio is not bigger than BIO_MAX_VECS sectors.

Unfortunately the same calltrace still could happen since an array could
enable write-behind without write mostly device.

To match the manpage of mdadm (which says "write-behind is only attempted
on drives marked as write-mostly"), we need to check WriteMostly flag to
avoid such unexpected behavior.

[1]. https://bugzilla.kernel.org/show_bug.cgi?id=213181#c25

Cc: stable@vger.kernel.org # v5.12+
Cc: Jens Stutte <jens@chianterastutte.eu>
Reported-by: Jens Stutte <jens@chianterastutte.eu>
Signed-off-by: Guoqing Jiang <guoqing.jiang@linux.dev>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-18 14:50:25 -06:00
Christoph Hellwig 7ad1069166 md: properly unwind when failing to add the kobject in md_alloc
Add proper error handling to delete the gendisk when failing to add
the md kobject and clean up the error unwinding in general.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-18 14:50:23 -06:00
Christoph Hellwig 94f3cd7d83 md: extend disks_mutex coverage
disks_mutex is intended to serialize md_alloc.  Extended it to also cover
the kobject_uevent call and getting the sysfs dirent to help reducing
error handling complexity.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-18 14:50:21 -06:00
Christoph Hellwig 51238e7fbd md: add the bitmap group to the default groups for the md kobject
Replace the deprecated default_attrs with the default_groups mechanism,
and add the always visible bitmap group to the groups created add
kobject_add time.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-18 14:50:19 -06:00
Luis Chamberlain 9be68dd7ac md: add error handling support for add_disk()
We never checked for errors on add_disk() as this function
returned void. Now that this is fixed, use the shiny new
error handling.

We just do the unwinding of what was not done before, and are
sure to unlock prior to bailing.

Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-18 14:50:10 -06:00
Christoph Hellwig 3e08773c38 block: switch polling to be bio based
Replace the blk_poll interface that requires the caller to keep a queue
and cookie from the submissions with polling based on the bio.

Polling for the bio itself leads to a few advantages:

 - the cookie construction can made entirely private in blk-mq.c
 - the caller does not need to remember the request_queue and cookie
   separately and thus sidesteps their lifetime issues
 - keeping the device and the cookie inside the bio allows to trivially
   support polling BIOs remapping by stacking drivers
 - a lot of code to propagate the cookie back up the submission path can
   be removed entirely.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Mark Wunderlich <mark.wunderlich@intel.com>
Link: https://lore.kernel.org/r/20211012111226.760968-15-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-18 06:17:36 -06:00
Christoph Hellwig 24b83deb29 block: move struct request to blk-mq.h
struct request is only used by blk-mq drivers, so move it and all
related declarations to blk-mq.h.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20210920123328.1399408-18-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-18 06:17:02 -06:00
Christoph Hellwig fe45e630a1 block: move integrity handling out of <linux/blkdev.h>
Split the integrity/metadata handling definitions out into a new header.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20210920123328.1399408-17-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-18 06:17:02 -06:00
Christoph Hellwig b81e0c2372 block: drop unused includes in <linux/genhd.h>
Drop various include not actually used in genhd.h itself, and
move the remaning includes closer together.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20210920123328.1399408-15-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-18 06:17:02 -06:00
Christoph Hellwig 3ab0bc78e9 block: drop unused includes in <linux/blkdev.h>
Drop various include not actually used in blkdev.h itself.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20210920123328.1399408-14-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-18 06:17:01 -06:00
Christoph Hellwig 1d9433cdd0 block: remove the unused rq_end_sector macro
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20210920123328.1399408-9-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-18 06:17:01 -06:00
Christoph Hellwig e41d12f539 mm: don't include <linux/blk-cgroup.h> in <linux/backing-dev.h>
There is no need to pull blk-cgroup.h and thus blkdev.h in here, so
break the include chain.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20210920123328.1399408-3-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-18 06:17:01 -06:00
Jiazi Li d208b89401 dm: fix mempool NULL pointer race when completing IO
dm_io_dec_pending() calls end_io_acct() first and will then dec md
in-flight pending count. But if a task is swapping DM table at same
time this can result in a crash due to mempool->elements being NULL:

task1                             task2
do_resume
 ->do_suspend
  ->dm_wait_for_completion
                                  bio_endio
				   ->clone_endio
				    ->dm_io_dec_pending
				     ->end_io_acct
				      ->wakeup task1
 ->dm_swap_table
  ->__bind
   ->__bind_mempools
    ->bioset_exit
     ->mempool_exit
                                     ->free_io

[ 67.330330] Unable to handle kernel NULL pointer dereference at
virtual address 0000000000000000
......
[ 67.330494] pstate: 80400085 (Nzcv daIf +PAN -UAO)
[ 67.330510] pc : mempool_free+0x70/0xa0
[ 67.330515] lr : mempool_free+0x4c/0xa0
[ 67.330520] sp : ffffff8008013b20
[ 67.330524] x29: ffffff8008013b20 x28: 0000000000000004
[ 67.330530] x27: ffffffa8c2ff40a0 x26: 00000000ffff1cc8
[ 67.330535] x25: 0000000000000000 x24: ffffffdada34c800
[ 67.330541] x23: 0000000000000000 x22: ffffffdada34c800
[ 67.330547] x21: 00000000ffff1cc8 x20: ffffffd9a1304d80
[ 67.330552] x19: ffffffdada34c970 x18: 000000b312625d9c
[ 67.330558] x17: 00000000002dcfbf x16: 00000000000006dd
[ 67.330563] x15: 000000000093b41e x14: 0000000000000010
[ 67.330569] x13: 0000000000007f7a x12: 0000000034155555
[ 67.330574] x11: 0000000000000001 x10: 0000000000000001
[ 67.330579] x9 : 0000000000000000 x8 : 0000000000000000
[ 67.330585] x7 : 0000000000000000 x6 : ffffff80148b5c1a
[ 67.330590] x5 : ffffff8008013ae0 x4 : 0000000000000001
[ 67.330596] x3 : ffffff80080139c8 x2 : ffffff801083bab8
[ 67.330601] x1 : 0000000000000000 x0 : ffffffdada34c970
[ 67.330609] Call trace:
[ 67.330616] mempool_free+0x70/0xa0
[ 67.330627] bio_put+0xf8/0x110
[ 67.330638] dec_pending+0x13c/0x230
[ 67.330644] clone_endio+0x90/0x180
[ 67.330649] bio_endio+0x198/0x1b8
[ 67.330655] dec_pending+0x190/0x230
[ 67.330660] clone_endio+0x90/0x180
[ 67.330665] bio_endio+0x198/0x1b8
[ 67.330673] blk_update_request+0x214/0x428
[ 67.330683] scsi_end_request+0x2c/0x300
[ 67.330688] scsi_io_completion+0xa0/0x710
[ 67.330695] scsi_finish_command+0xd8/0x110
[ 67.330700] scsi_softirq_done+0x114/0x148
[ 67.330708] blk_done_softirq+0x74/0xd0
[ 67.330716] __do_softirq+0x18c/0x374
[ 67.330724] irq_exit+0xb4/0xb8
[ 67.330732] __handle_domain_irq+0x84/0xc0
[ 67.330737] gic_handle_irq+0x148/0x1b0
[ 67.330744] el1_irq+0xe8/0x190
[ 67.330753] lpm_cpuidle_enter+0x4f8/0x538
[ 67.330759] cpuidle_enter_state+0x1fc/0x398
[ 67.330764] cpuidle_enter+0x18/0x20
[ 67.330772] do_idle+0x1b4/0x290
[ 67.330778] cpu_startup_entry+0x20/0x28
[ 67.330786] secondary_start_kernel+0x160/0x170

Fix this by:
1) Establishing pointers to 'struct dm_io' members in
dm_io_dec_pending() so that they may be passed into end_io_acct()
_after_ free_io() is called.
2) Moving end_io_acct() after free_io().

Cc: stable@vger.kernel.org
Signed-off-by: Jiazi Li <lijiazi@xiaomi.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-10-12 13:54:10 -04:00
Ming Lei b4459b11e8 dm rq: don't queue request to blk-mq during DM suspend
DM uses blk-mq's quiesce/unquiesce to stop/start device mapper queue.

But blk-mq's unquiesce may come from outside events, such as elevator
switch, updating nr_requests or others, and request may come during
suspend, so simply ask for blk-mq to requeue it.

Fixes one kernel panic issue when running updating nr_requests and
dm-mpath suspend/resume stress test.

Cc: stable@vger.kernel.org
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-10-12 13:54:10 -04:00
Colin Ian King ec132ef2d1 dm clone: make array 'descs' static
Don't populate the read-only array descs on the stack but instead it
static and add extra const. Also makes the object code smaller by 66
bytes:

Before:
   text    data     bss     dec     hex filename
  42382   11140     512   54034    d312 ./drivers/md/dm-clone-target.o

After:
   text    data     bss     dec     hex filename
  42220   11236     512   53968    d2d0 ./drivers/md/dm-clone-target.o

(gcc version 11.2.0)

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-10-12 13:54:10 -04:00
Akilesh Kailash 2c0468e054 dm verity: skip redundant verity_handle_err() on I/O errors
Without FEC, dm-verity won't call verity_handle_err() when I/O fails,
but with FEC enabled, it currently does even if an I/O error has
occurred.

If there is an I/O error and FEC correction fails, return the error
instead of calling verity_handle_err() again.

Suggested-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Akilesh Kailash <akailash@google.com>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-10-12 13:54:09 -04:00
Christoph Hellwig 7df835a32a md: fix a lock order reversal in md_alloc
Commit b0140891a8 ("md: Fix race when creating a new md device.")
not only moved assigning mddev->gendisk before calling add_disk, which
fixes the races described in the commit log, but also added a
mddev->open_mutex critical section over add_disk and creation of the
md kobj.  Adding a kobject after add_disk is racy vs deleting the gendisk
right after adding it, but md already prevents against that by holding
a mddev->active reference.

On the other hand taking this lock added a lock order reversal with what
is not disk->open_mutex (used to be bdev->bd_mutex when the commit was
added) for partition devices, which need that lock for the internal open
for the partition scan, and a recent commit also takes it for
non-partitioned devices, leading to further lockdep splatter.

Fixes: b0140891a8 ("md: Fix race when creating a new md device.")
Fixes: d626338735 ("block: support delayed holder registration")
Reported-by: syzbot+fadc0aaf497e6a493b9f@syzkaller.appspotmail.com
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: syzbot+fadc0aaf497e6a493b9f@syzkaller.appspotmail.com
Reviewed-by: NeilBrown <neilb@suse.de>
Signed-off-by: Song Liu <songliubraving@fb.com>
2021-09-22 08:45:58 -07:00
Linus Torvalds 2e5fd489a4 libnvdimm for v5.15
- Fix a race condition in the teardown path of raw mode pmem namespaces.
 
 - Cleanup the code that filesystems use to detect filesystem-dax
   capabilities of their underlying block device.
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Merge tag 'libnvdimm-for-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

Pull libnvdimm updates from Dan Williams:

 - Fix a race condition in the teardown path of raw mode pmem
   namespaces.

 - Cleanup the code that filesystems use to detect filesystem-dax
   capabilities of their underlying block device.

* tag 'libnvdimm-for-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  dax: remove bdev_dax_supported
  xfs: factor out a xfs_buftarg_is_dax helper
  dax: stub out dax_supported for !CONFIG_FS_DAX
  dax: remove __generic_fsdax_supported
  dax: move the dax_read_lock() locking into dax_supported
  dax: mark dax_get_by_host static
  dm: use fs_dax_get_by_bdev instead of dax_get_by_host
  dax: stop using bdevname
  fsdax: improve the FS_DAX Kconfig description and help text
  libnvdimm/pmem: Fix crash triggered when I/O in-flight during unbind
2021-09-09 11:39:57 -07:00
Linus Torvalds aef4892a63 integrity-v5.15
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Merge tag 'integrity-v5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity

Pull integrity subsystem updates from Mimi Zohar:

 - Limit the allowed hash algorithms when writing security.ima xattrs or
   verifying them, based on the IMA policy and the configured hash
   algorithms.

 - Return the calculated "critical data" measurement hash and size to
   avoid code duplication. (Preparatory change for a proposed LSM.)

 - and a single patch to address a compiler warning.

* tag 'integrity-v5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity:
  IMA: reject unknown hash algorithms in ima_get_hash_algo
  IMA: prevent SETXATTR_CHECK policy rules with unavailable algorithms
  IMA: introduce a new policy option func=SETXATTR_CHECK
  IMA: add a policy option to restrict xattr hash algorithms on appraisal
  IMA: add support to restrict the hash algorithms used for file appraisal
  IMA: block writes of the security.ima xattr with unsupported algorithms
  IMA: remove the dependency on CRYPTO_MD5
  ima: Add digest and digest_len params to the functions to measure a buffer
  ima: Return int in the functions to measure a buffer
  ima: Introduce ima_get_current_hash_algo()
  IMA: remove -Wmissing-prototypes warning
2021-09-02 12:51:41 -07:00
Linus Torvalds efa916af13 - Add DM infrastructure for IMA-based remote attestion. These changes
are the basis for deploying DM-based storage in a "cloud" that must
   validate configurations end-users run to maintain trust. These DM
   changes allow supported DM targets' configurations to be measured
   via IMA. But the policy and enforcement (of which configurations are
   valid) is managed by something outside the kernel (e.g. Keylime).
 
 - Fix DM crypt scalability regression on systems with many cpus due to
   percpu_counter spinlock contention in crypt_page_alloc().
 
 - Use in_hardirq() instead of deprecated in_irq() in DM crypt.
 
 - Add event counters to DM writecache to allow users to further assess
   how the writecache is performing.
 
 - Various code cleanup in DM writecache's main IO mapping function.
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Merge tag 'for-5.15/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

Pull device mapper updates from Mike Snitzer:

 - Add DM infrastructure for IMA-based remote attestion. These changes
   are the basis for deploying DM-based storage in a "cloud" that must
   validate configurations end-users run to maintain trust. These DM
   changes allow supported DM targets' configurations to be measured via
   IMA. But the policy and enforcement (of which configurations are
   valid) is managed by something outside the kernel (e.g. Keylime).

 - Fix DM crypt scalability regression on systems with many cpus due to
   percpu_counter spinlock contention in crypt_page_alloc().

 - Use in_hardirq() instead of deprecated in_irq() in DM crypt.

 - Add event counters to DM writecache to allow users to further assess
   how the writecache is performing.

 - Various code cleanup in DM writecache's main IO mapping function.

* tag 'for-5.15/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
  dm crypt: use in_hardirq() instead of deprecated in_irq()
  dm ima: update dm documentation for ima measurement support
  dm ima: update dm target attributes for ima measurements
  dm ima: add a warning in dm_init if duplicate ima events are not measured
  dm ima: prefix ima event name related to device mapper with dm_
  dm ima: add version info to dm related events in ima log
  dm ima: prefix dm table hashes in ima log with hash algorithm
  dm crypt: Avoid percpu_counter spinlock contention in crypt_page_alloc()
  dm: add documentation for IMA measurement support
  dm: update target status functions to support IMA measurement
  dm ima: measure data on device rename
  dm ima: measure data on table clear
  dm ima: measure data on device remove
  dm ima: measure data on device resume
  dm ima: measure data on table load
  dm writecache: add event counters
  dm writecache: report invalid return from writecache_map helpers
  dm writecache: further writecache_map() cleanup
  dm writecache: factor out writecache_map_remap_origin()
  dm writecache: split up writecache_map() to improve code readability
2021-08-31 14:55:09 -07:00
Linus Torvalds 9a1d6c9e3f for-5.15/drivers-2021-08-30
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Merge tag 'for-5.15/drivers-2021-08-30' of git://git.kernel.dk/linux-block

Pull block driver updates from Jens Axboe:
 "Sitting on top of the core block changes, here are the driver changes
  for the 5.15 merge window:

   - NVMe updates via Christoph:
       - suspend improvements for devices with an HMB (Keith Busch)
       - handle double completions more gacefull (Sagi Grimberg)
       - cleanup the selects for the nvme core code a bit (Sagi Grimberg)
       - don't update queue count when failing to set io queues (Ruozhu Li)
       - various nvmet connect fixes (Amit Engel)
       - cleanup lightnvm leftovers (Keith Busch, me)
       - small cleanups (Colin Ian King, Hou Pu)
       - add tracing for the Set Features command (Hou Pu)
       - CMB sysfs cleanups (Keith Busch)
       - add a mutex_destroy call (Keith Busch)

   - remove lightnvm subsystem. It's served its purpose and ultimately
     led to zoned nvme support, we no longer need it (Christoph)

   - revert floppy O_NDELAY fix (Denis)

   - nbd fixes (Hou, Pavel, Baokun)

   - nbd locking fixes (Tetsuo)

   - nbd device removal fixes (Christoph)

   - raid10 rcu warning fix (Xiao)

   - raid1 write behind fix (Guoqing)

   - rnbd fixes (Gioh, Md Haris)

   - misc fixes (Colin)"

* tag 'for-5.15/drivers-2021-08-30' of git://git.kernel.dk/linux-block: (42 commits)
  Revert "floppy: reintroduce O_NDELAY fix"
  raid1: ensure write behind bio has less than BIO_MAX_VECS sectors
  md/raid10: Remove unnecessary rcu_dereference in raid10_handle_discard
  nbd: remove nbd->destroy_complete
  nbd: only return usable devices from nbd_find_unused
  nbd: set nbd->index before releasing nbd_index_mutex
  nbd: prevent IDR lookups from finding partially initialized devices
  nbd: reset NBD to NULL when restarting in nbd_genl_connect
  nbd: add missing locking to the nbd_dev_add error path
  nvme: remove the unused NVME_NS_* enum
  nvme: remove nvm_ndev from ns
  nvme: Have NVME_FABRICS select NVME_CORE instead of transport drivers
  block: nbd: add sanity check for first_minor
  nvmet: check that host sqsize does not exceed ctrl MQES
  nvmet: avoid duplicate qid in connect cmd
  nvmet: pass back cntlid on successful completion
  nvme-rdma: don't update queue count when failing to set io queues
  nvme-tcp: don't update queue count when failing to set io queues
  nvme-tcp: pair send_mutex init with destroy
  nvme: allow user toggling hmb usage
  ...
2021-08-30 19:01:46 -07:00
Linus Torvalds 679369114e for-5.15/block-2021-08-30
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Merge tag 'for-5.15/block-2021-08-30' of git://git.kernel.dk/linux-block

Pull block updates from Jens Axboe:
 "Nothing major in here - lots of good cleanups and tech debt handling,
  which is also evident in the diffstats. In particular:

   - Add disk sequence numbers (Matteo)

   - Discard merge fix (Ming)

   - Relax disk zoned reporting restrictions (Niklas)

   - Bio error handling zoned leak fix (Pavel)

   - Start of proper add_disk() error handling (Luis, Christoph)

   - blk crypto fix (Eric)

   - Non-standard GPT location support (Dmitry)

   - IO priority improvements and cleanups (Damien)o

   - blk-throtl improvements (Chunguang)

   - diskstats_show() stack reduction (Abd-Alrhman)

   - Loop scheduler selection (Bart)

   - Switch block layer to use kmap_local_page() (Christoph)

   - Remove obsolete disk_name helper (Christoph)

   - block_device refcounting improvements (Christoph)

   - Ensure gendisk always has a request queue reference (Christoph)

   - Misc fixes/cleanups (Shaokun, Oliver, Guoqing)"

* tag 'for-5.15/block-2021-08-30' of git://git.kernel.dk/linux-block: (129 commits)
  sg: pass the device name to blk_trace_setup
  block, bfq: cleanup the repeated declaration
  blk-crypto: fix check for too-large dun_bytes
  blk-zoned: allow BLKREPORTZONE without CAP_SYS_ADMIN
  blk-zoned: allow zone management send operations without CAP_SYS_ADMIN
  block: mark blkdev_fsync static
  block: refine the disk_live check in del_gendisk
  mmc: sdhci-tegra: Enable MMC_CAP2_ALT_GPT_TEGRA
  mmc: block: Support alternative_gpt_sector() operation
  partitions/efi: Support non-standard GPT location
  block: Add alternative_gpt_sector() operation
  bio: fix page leak bio_add_hw_page failure
  block: remove CONFIG_DEBUG_BLOCK_EXT_DEVT
  block: remove a pointless call to MINOR() in device_add_disk
  null_blk: add error handling support for add_disk()
  virtio_blk: add error handling support for add_disk()
  block: add error handling for device_add_disk / add_disk
  block: return errors from disk_alloc_events
  block: return errors from blk_integrity_add
  block: call blk_register_queue earlier in device_add_disk
  ...
2021-08-30 18:52:11 -07:00
Sebastian Andrzej Siewior 252034e03f md/raid5: Replace deprecated CPU-hotplug functions.
The functions get_online_cpus() and put_online_cpus() have been
deprecated during the CPU hotplug rework. They map directly to
cpus_read_lock() and cpus_read_unlock().

Replace deprecated CPU-hotplug functions with the official version.
The behavior remains unchanged.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20210803141621.780504-16-bigeasy@linutronix.de
2021-08-28 01:46:17 +02:00
Guoqing Jiang 6607cd319b raid1: ensure write behind bio has less than BIO_MAX_VECS sectors
We can't split write behind bio with more than BIO_MAX_VECS sectors,
otherwise the below call trace was triggered because we could allocate
oversized write behind bio later.

[ 8.097936] bvec_alloc+0x90/0xc0
[ 8.098934] bio_alloc_bioset+0x1b3/0x260
[ 8.099959] raid1_make_request+0x9ce/0xc50 [raid1]
[ 8.100988] ? __bio_clone_fast+0xa8/0xe0
[ 8.102008] md_handle_request+0x158/0x1d0 [md_mod]
[ 8.103050] md_submit_bio+0xcd/0x110 [md_mod]
[ 8.104084] submit_bio_noacct+0x139/0x530
[ 8.105127] submit_bio+0x78/0x1d0
[ 8.106163] ext4_io_submit+0x48/0x60 [ext4]
[ 8.107242] ext4_writepages+0x652/0x1170 [ext4]
[ 8.108300] ? do_writepages+0x41/0x100
[ 8.109338] ? __ext4_mark_inode_dirty+0x240/0x240 [ext4]
[ 8.110406] do_writepages+0x41/0x100
[ 8.111450] __filemap_fdatawrite_range+0xc5/0x100
[ 8.112513] file_write_and_wait_range+0x61/0xb0
[ 8.113564] ext4_sync_file+0x73/0x370 [ext4]
[ 8.114607] __x64_sys_fsync+0x33/0x60
[ 8.115635] do_syscall_64+0x33/0x40
[ 8.116670] entry_SYSCALL_64_after_hwframe+0x44/0xae

Thanks for the comment from Christoph.

[1]. https://bugs.archlinux.org/task/70992

Cc: stable@vger.kernel.org # v5.12+
Reported-by: Jens Stutte <jens@chianterastutte.eu>
Tested-by: Jens Stutte <jens@chianterastutte.eu>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Guoqing Jiang <jiangguoqing@kylinos.cn>
Signed-off-by: Song Liu <songliubraving@fb.com>
2021-08-27 15:12:14 -07:00
Christoph Hellwig 673a0658f6 dax: move the dax_read_lock() locking into dax_supported
Move the dax_read_lock/dax_read_unlock pair from the callers into
dax_supported to make it a little easier to use.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Link: https://lore.kernel.org/r/20210826135510.6293-6-hch@lst.de
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-08-26 16:52:03 -07:00
Christoph Hellwig dfa584f6f9 dm: use fs_dax_get_by_bdev instead of dax_get_by_host
There is no point in trying to finding the dax device if the DAX flag is
not set on the queue as none of the users of the device mapper exported
block devices could make use of the DAX capability.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Mike Snitzer <snitzer@redhat.com>
Link: https://lore.kernel.org/r/20210826135510.6293-4-hch@lst.de
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-08-26 16:52:03 -07:00
Xiao Ni 46d4703b1d md/raid10: Remove unnecessary rcu_dereference in raid10_handle_discard
We are seeing the following warning in raid10_handle_discard.
[  695.110751] =============================
[  695.131439] WARNING: suspicious RCU usage
[  695.151389] 4.18.0-319.el8.x86_64+debug #1 Not tainted
[  695.174413] -----------------------------
[  695.192603] drivers/md/raid10.c:1776 suspicious
rcu_dereference_check() usage!
[  695.225107] other info that might help us debug this:
[  695.260940] rcu_scheduler_active = 2, debug_locks = 1
[  695.290157] no locks held by mkfs.xfs/10186.

In the first loop of function raid10_handle_discard. It already
determines which disk need to handle discard request and add the
rdev reference count rdev->nr_pending. So the conf->mirrors will
not change until all bios come back from underlayer disks. It
doesn't need to use rcu_dereference to get rdev.

Cc: stable@vger.kernel.org
Fixes: d30588b273 ('md/raid10: improve raid10 discard request')
Signed-off-by: Xiao Ni <xni@redhat.com>
Acked-by: Guoqing Jiang <guoqing.jiang@linux.dev>
Signed-off-by: Song Liu <songliubraving@fb.com>
2021-08-26 09:04:15 -07:00
Changbin Du d3703ef331 dm crypt: use in_hardirq() instead of deprecated in_irq()
Signed-off-by: Changbin Du <changbin.du@gmail.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-08-20 16:25:07 -04:00
Tushar Sugandhi 33ace4ca12 dm ima: update dm target attributes for ima measurements
Certain DM targets ('integrity', 'multipath', 'verity') need to update the
way their attributes are recorded in the ima log, so that the attestation
servers can interpret the data correctly and decide if the devices
meet the attestation requirements.  For instance, the "mode=%c" attribute
in the 'integrity' target is measured twice, the 'verity' target is
missing the attribute "root_hash_sig_key_desc=%s", and the 'multipath'
target needs to index the attributes properly.

Update 'integrity' target to remove the duplicate measurement of
the attribute "mode=%c".  Add "root_hash_sig_key_desc=%s" attribute
for the 'verity' target.  Index various attributes in 'multipath'
target.  Also, add "nr_priority_groups=%u" attribute to 'multipath'
target to record the number of priority groups.

Signed-off-by: Tushar Sugandhi <tusharsu@linux.microsoft.com>
Suggested-by: Thore Sommer <public@thson.de>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-08-20 16:07:36 -04:00
Tushar Sugandhi f1cd6cb24b dm ima: add a warning in dm_init if duplicate ima events are not measured
The end-users of DM devices/targets may remove and re-create the same
device multiple times.  IMA does not measure such duplicate events if the
configuration CONFIG_IMA_DISABLE_HTABLE is set to 'n'.
To avoid confusion, the end-users need some indication on the client
if that configuration option is disabled.

Add a one-time warning during dm_init() if CONFIG_IMA_DISABLE_HTABLE
is set to 'n', to notify the end-users that duplicate events will not
be measured in the ima log. Also cleanup some whitespace in dm_init().

Signed-off-by: Tushar Sugandhi <tusharsu@linux.microsoft.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-08-20 16:07:35 -04:00
Tushar Sugandhi 9c2adfa6ba dm ima: prefix ima event name related to device mapper with dm_
The event names for the DM events recorded in the ima log do not contain
any information to indicate the events are part of the DM devices/targets.

Prefix the event names for DM events with "dm_" to indicate that they
are part of device-mapper.

Signed-off-by: Tushar Sugandhi <tusharsu@linux.microsoft.com>
Suggested-by: Thore Sommer <public@thson.de>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-08-20 16:00:36 -04:00
Tushar Sugandhi dc7b79cc24 dm ima: add version info to dm related events in ima log
The DM events present in the ima log contain various attributes in the
key=value format.  The attributes' names/values may change in future,
and new attributes may also get added.  The attestation server needs
some versioning to determine which attributes are supported and are
expected in the ima log.

Add version information to the DM events present in the ima log to
help attestation servers to correctly process the attributes across
different versions.

Signed-off-by: Tushar Sugandhi <tusharsu@linux.microsoft.com>
Suggested-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-08-20 15:59:47 -04:00
Tushar Sugandhi 8f509fd4a5 dm ima: prefix dm table hashes in ima log with hash algorithm
The active/inactive table hashes measured in the ima log do not contain
the information about hash algorithm.  This information is useful for the
attestation servers to recreate the hashes and compare them with the ones
present in the ima log to verify the table contents.

Prefix the table hashes in various DM events in ima log with the hash
algorithm used to compute those hashes.

Signed-off-by: Tushar Sugandhi <tusharsu@linux.microsoft.com>
Suggested-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-08-20 15:59:43 -04:00
Arne Welzel 528b16bfc3 dm crypt: Avoid percpu_counter spinlock contention in crypt_page_alloc()
On systems with many cores using dm-crypt, heavy spinlock contention in
percpu_counter_compare() can be observed when the page allocation limit
for a given device is reached or close to be reached. This is due
to percpu_counter_compare() taking a spinlock to compute an exact
result on potentially many CPUs at the same time.

Switch to non-exact comparison of allocated and allowed pages by using
the value returned by percpu_counter_read_positive() to avoid taking
the percpu_counter spinlock.

This may over/under estimate the actual number of allocated pages by at
most (batch-1) * num_online_cpus().

Currently, batch is bounded by 32. The system on which this issue was
first observed has 256 CPUs and 512GB of RAM. With a 4k page size, this
change may over/under estimate by 31MB. With ~10G (2%) allowed dm-crypt
allocations, this seems an acceptable error. Certainly preferred over
running into the spinlock contention.

This behavior was reproduced on an EC2 c5.24xlarge instance with 96 CPUs
and 192GB RAM as follows, but can be provoked on systems with less CPUs
as well.

 * Disable swap
 * Tune vm settings to promote regular writeback
     $ echo 50 > /proc/sys/vm/dirty_expire_centisecs
     $ echo 25 > /proc/sys/vm/dirty_writeback_centisecs
     $ echo $((128 * 1024 * 1024)) > /proc/sys/vm/dirty_background_bytes

 * Create 8 dmcrypt devices based on files on a tmpfs
 * Create and mount an ext4 filesystem on each crypt devices
 * Run stress-ng --hdd 8 within one of above filesystems

Total %system usage collected from sysstat goes to ~35%. Write throughput
on the underlying loop device is ~2GB/s. perf profiling an individual
kworker kcryptd thread shows the following profile, indicating spinlock
contention in percpu_counter_compare():

    99.98%     0.00%  kworker/u193:46  [kernel.kallsyms]  [k] ret_from_fork
      |
      --ret_from_fork
        kthread
        worker_thread
        |
         --99.92%--process_one_work
            |
            |--80.52%--kcryptd_crypt
            |    |
            |    |--62.58%--mempool_alloc
            |    |  |
            |    |   --62.24%--crypt_page_alloc
            |    |     |
            |    |      --61.51%--__percpu_counter_compare
            |    |        |
            |    |         --61.34%--__percpu_counter_sum
            |    |           |
            |    |           |--58.68%--_raw_spin_lock_irqsave
            |    |           |  |
            |    |           |   --58.30%--native_queued_spin_lock_slowpath
            |    |           |
            |    |            --0.69%--cpumask_next
            |    |                |
            |    |                 --0.51%--_find_next_bit
            |    |
            |    |--10.61%--crypt_convert
            |    |          |
            |    |          |--6.05%--xts_crypt
            ...

After applying this patch and running the same test, %system usage is
lowered to ~7% and write throughput on the loop device increases
to ~2.7GB/s. perf report shows mempool_alloc() as ~8% rather than ~62%
in the profile and not hitting the percpu_counter() spinlock anymore.

    |--8.15%--mempool_alloc
    |    |
    |    |--3.93%--crypt_page_alloc
    |    |    |
    |    |     --3.75%--__alloc_pages
    |    |         |
    |    |          --3.62%--get_page_from_freelist
    |    |              |
    |    |               --3.22%--rmqueue_bulk
    |    |                   |
    |    |                    --2.59%--_raw_spin_lock
    |    |                      |
    |    |                       --2.57%--native_queued_spin_lock_slowpath
    |    |
    |     --3.05%--_raw_spin_lock_irqsave
    |               |
    |                --2.49%--native_queued_spin_lock_slowpath

Suggested-by: DJ Gregor <dj@corelight.com>
Reviewed-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Arne Welzel <arne.welzel@corelight.com>
Fixes: 5059353df8 ("dm crypt: limit the number of allocated pages")
Cc: stable@vger.kernel.org
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-08-18 02:10:48 -04:00
Christoph Hellwig 2fd3e5efe7 bcache: use bvec_virt
Use bvec_virt instead of open coding it.  Note that the existing code is
fine despite ignoring bv_offset as the bio is known to contain exactly
one page from the page allocator per bio_vec.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Coly Li <colyli@suse.de>
Link: https://lore.kernel.org/r/20210804095634.460779-10-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-08-16 10:50:33 -06:00