Commit Graph

4762 Commits

Author SHA1 Message Date
Balbir Singh
e598a72fae block/genhd: Notify udev about capacity change
Allow block/genhd to notify user space (via udev) about disk size changes
using a new helper set_capacity_revalidate_and_notify(), which is a wrapper
on top of set_capacity(). set_capacity_revalidate_and_notify() will only
notify via udev if the current capacity or the target capacity is not zero
and iff the capacity changes.

Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Someswarudu Sangaraju <ssomesh@amazon.com>
Signed-off-by: Balbir Singh <sblbir@amazon.com>
Reviewed-by: Bob Liu <bob.liu@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-03-18 15:13:21 -06:00
Ming Lei
de6a78b601 block: Prevent hung_check firing during long sync IO
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 <sqazi@google.com>
Cc: Jesse Barnes <jsbarnes@google.com>
Cc: Bart Van Assche <bvanassche@acm.org>
Link: https://lkml.org/lkml/2020/2/12/1193
Reported-by: Salman Qazi <sqazi@google.com>
Reviewed-by: Jesse Barnes <jsbarnes@google.com>
Reviewed-by: Salman Qazi <sqazi@google.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-03-18 08:48:03 -06:00
Alexey Dobriyan
11bde98600 block, zoned: fix integer overflow with BLKRESETZONE et al
Check for overflow in addition before checking for end-of-block-device.

Steps to reproduce:

	#define _GNU_SOURCE 1
	#include <sys/ioctl.h>
	#include <sys/types.h>
	#include <sys/stat.h>
	#include <fcntl.h>

	typedef unsigned long long __u64;

	struct blk_zone_range {
	        __u64 sector;
	        __u64 nr_sectors;
	};

	#define BLKRESETZONE    _IOW(0x12, 131, struct blk_zone_range)

	int main(void)
	{
	        int fd = open("/dev/nullb0", O_RDWR|O_DIRECT);
	        struct blk_zone_range zr = {4096, 0xfffffffffffff000ULL};
	        ioctl(fd, BLKRESETZONE, &zr);
	        return 0;
	}

BUG: KASAN: null-ptr-deref in submit_bio_wait+0x74/0xe0
Write of size 8 at addr 0000000000000040 by task a.out/1590

CPU: 8 PID: 1590 Comm: a.out Not tainted 5.6.0-rc1-00019-g359c92c02bfa #2
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20190711_202441-buildvm-armv7-10.arm.fedoraproject.org-2.fc31 04/01/2014
Call Trace:
 dump_stack+0x76/0xa0
 __kasan_report.cold+0x5/0x3e
 kasan_report+0xe/0x20
 submit_bio_wait+0x74/0xe0
 blkdev_zone_mgmt+0x26f/0x2a0
 blkdev_zone_mgmt_ioctl+0x14b/0x1b0
 blkdev_ioctl+0xb28/0xe60
 block_ioctl+0x69/0x80
 ksys_ioctl+0x3af/0xa50

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alexey Dobriyan (SK hynix) <adobriyan@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-03-12 09:10:52 -06:00
Weiping Zhang
fa800d73c8 blk-iocost: remove duplicated lines in comments
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Weiping Zhang <zhangweiping@didiglobal.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-03-12 08:02:20 -06:00
Revanth Rajashekar
88d6041d07 block: sed-opal: Change the check condition for regular session validity
This patch changes the check condition for the validity/authentication
of the session.

1. The Host Session Number(HSN) in the response should match the HSN for
   the session.
2. The TPER Session Number(TSN) can never be less than 4096 for a regular
   session.

Reference:
Section 3.2.2.1   of https://trustedcomputinggroup.org/wp-content/uploads/TCG_Storage_Opal_SSC_Application_Note_1-00_1-00-Final.pdf
Section 3.3.7.1.1 of https://trustedcomputinggroup.org/wp-content/uploads/TCG_Storage_Architecture_Core_Spec_v2.01_r1.00.pdf

Co-developed-by: Andrzej Jakowski <andrzej.jakowski@linux.intel.com>
Signed-off-by: Andrzej Jakowski <andrzej.jakowski@linux.intel.com>
Signed-off-by: Revanth Rajashekar <revanth.rajashekar@intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-03-12 08:00:10 -06:00
Guoqing Jiang
ce24f736f2 block: cleanup comment for blk_flush_complete_seq
Remove the comment about return value, since it is not valid after
commit 404b8f5a03 ("block: cleanup kick/queued handling").

Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-03-12 07:42:54 -06:00
Guoqing Jiang
754a15726f block: remove unneeded argument from blk_alloc_flush_queue
Remove 'q' from arguments since it is not used anymore after
commit 7e992f847a ("block: remove non mq parts from the
flush code").

Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-03-12 07:42:54 -06:00
Guoqing Jiang
361301a222 block: cleanup for _blk/blk_rq_prep_clone
Both cmd and sense had been moved to scsi_request, so remove
the related comments to avoid confusion.

And as Bart suggested, move _blk_rq_prep_clone into the only
caller (blk_rq_prep_clone).

Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-03-12 07:42:54 -06:00
Guoqing Jiang
fc4cc77210 block: remove redundant setting of QUEUE_FLAG_DYING
Previously, blk_cleanup_queue has called blk_set_queue_dying to set the
flag, no need to do it again.

Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-03-12 07:42:54 -06:00
Guoqing Jiang
35ed78b32c block: use bio_{wouldblock,io}_error in direct_make_request
Use the two functions to simplify code.

Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-03-12 07:42:54 -06:00
Guoqing Jiang
0d72031820 block: fix comment for blk_cloned_rq_check_limits
Since the later description mentioned "checked against the new queue
limits", so make the change to avoid confusion.

Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-03-12 07:42:54 -06:00
Sahitya Tummala
30a2da7b7e block: Fix use-after-free issue accessing struct io_cq
There is a potential race between ioc_release_fn() and
ioc_clear_queue() as shown below, due to which below kernel
crash is observed. It also can result into use-after-free
issue.

context#1:				context#2:
ioc_release_fn()			__ioc_clear_queue() gets the same icq
->spin_lock(&ioc->lock);		->spin_lock(&ioc->lock);
->ioc_destroy_icq(icq);
  ->list_del_init(&icq->q_node);
  ->call_rcu(&icq->__rcu_head,
  	icq_free_icq_rcu);
->spin_unlock(&ioc->lock);
					->ioc_destroy_icq(icq);
					  ->hlist_del_init(&icq->ioc_node);
					  This results into below crash as this memory
					  is now used by icq->__rcu_head in context#1.
					  There is a chance that icq could be free'd
					  as well.

22150.386550:   <6> Unable to handle kernel write to read-only memory
at virtual address ffffffaa8d31ca50
...
Call trace:
22150.607350:   <2>  ioc_destroy_icq+0x44/0x110
22150.611202:   <2>  ioc_clear_queue+0xac/0x148
22150.615056:   <2>  blk_cleanup_queue+0x11c/0x1a0
22150.619174:   <2>  __scsi_remove_device+0xdc/0x128
22150.623465:   <2>  scsi_forget_host+0x2c/0x78
22150.627315:   <2>  scsi_remove_host+0x7c/0x2a0
22150.631257:   <2>  usb_stor_disconnect+0x74/0xc8
22150.635371:   <2>  usb_unbind_interface+0xc8/0x278
22150.639665:   <2>  device_release_driver_internal+0x198/0x250
22150.644897:   <2>  device_release_driver+0x24/0x30
22150.649176:   <2>  bus_remove_device+0xec/0x140
22150.653204:   <2>  device_del+0x270/0x460
22150.656712:   <2>  usb_disable_device+0x120/0x390
22150.660918:   <2>  usb_disconnect+0xf4/0x2e0
22150.664684:   <2>  hub_event+0xd70/0x17e8
22150.668197:   <2>  process_one_work+0x210/0x480
22150.672222:   <2>  worker_thread+0x32c/0x4c8

Fix this by adding a new ICQ_DESTROYED flag in ioc_destroy_icq() to
indicate this icq is once marked as destroyed. Also, ensure
__ioc_clear_queue() is accessing icq within rcu_read_lock/unlock so
that icq doesn't get free'd up while it is still using it.

Signed-off-by: Sahitya Tummala <stummala@codeaurora.org>
Co-developed-by: Pradeep P V K <ppvk@codeaurora.org>
Signed-off-by: Pradeep P V K <ppvk@codeaurora.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-03-12 07:07:38 -06:00
Bart Van Assche
d0930bb8f4 blk-mq: Fix a recently introduced regression in blk_mq_realloc_hw_ctxs()
q->nr_hw_queues must only be updated once it is known that
blk_mq_realloc_hw_ctxs() has succeeded. Otherwise it can happen that
reallocation fails and that q->nr_hw_queues is larger than the number of
allocated hardware queues. This patch fixes the following crash if
increasing the number of hardware queues fails:

BUG: KASAN: null-ptr-deref in blk_mq_map_swqueue+0x775/0x810
Write of size 8 at addr 0000000000000118 by task check/977

CPU: 3 PID: 977 Comm: check Not tainted 5.6.0-rc1-dbg+ #8
Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
Call Trace:
 dump_stack+0xa5/0xe6
 __kasan_report.cold+0x65/0x99
 kasan_report+0x16/0x20
 check_memory_region+0x140/0x1b0
 memset+0x28/0x40
 blk_mq_map_swqueue+0x775/0x810
 blk_mq_update_nr_hw_queues+0x468/0x710
 nullb_device_submit_queues_store+0xf7/0x1a0 [null_blk]
 configfs_write_file+0x1c4/0x250 [configfs]
 __vfs_write+0x4c/0x90
 vfs_write+0x145/0x2c0
 ksys_write+0xd7/0x180
 __x64_sys_write+0x47/0x50
 do_syscall_64+0x6f/0x2f0
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Fixes: ac0d6b926e ("block: Reduce the amount of memory required per request queue")
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Cc: Keith Busch <kbusch@kernel.org>
Cc: Johannes Thumshirn <jth@kernel.org>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-03-10 07:09:59 -06:00
Bart Van Assche
6e66b49392 blk-mq: Keep set->nr_hw_queues and set->map[].nr_queues in sync
blk_mq_map_queues() and multiple .map_queues() implementations expect that
set->map[HCTX_TYPE_DEFAULT].nr_queues is set to the number of hardware
queues. Hence set .nr_queues before calling these functions. This patch
fixes the following kernel warning:

WARNING: CPU: 0 PID: 2501 at include/linux/cpumask.h:137
Call Trace:
 blk_mq_run_hw_queue+0x19d/0x350 block/blk-mq.c:1508
 blk_mq_run_hw_queues+0x112/0x1a0 block/blk-mq.c:1525
 blk_mq_requeue_work+0x502/0x780 block/blk-mq.c:775
 process_one_work+0x9af/0x1740 kernel/workqueue.c:2269
 worker_thread+0x98/0xe40 kernel/workqueue.c:2415
 kthread+0x361/0x430 kernel/kthread.c:255

Fixes: ed76e329d7 ("blk-mq: abstract out queue map") # v5.0
Reported-by: syzbot+d44e1b26ce5c3e77458d@syzkaller.appspotmail.com
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Cc: Johannes Thumshirn <jth@kernel.org>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-03-10 07:09:59 -06:00
Carlo Nonato
14afc59361 block, bfq: fix overwrite of bfq_group pointer in bfq_find_set_group()
The bfq_find_set_group() function takes as input a blkcg (which represents
a cgroup) and retrieves the corresponding bfq_group, then it updates the
bfq internal group hierarchy (see comments inside the function for why
this is needed) and finally it returns the bfq_group.
In the hierarchy update cycle, the pointer holding the correct bfq_group
that has to be returned is mistakenly used to traverse the hierarchy
bottom to top, meaning that in each iteration it gets overwritten with the
parent of the current group. Since the update cycle stops at root's
children (depth = 2), the overwrite becomes a problem only if the blkcg
describes a cgroup at a hierarchy level deeper than that (depth > 2). In
this case the root's child that happens to be also an ancestor of the
correct bfq_group is returned. The main consequence is that processes
contained in a cgroup at depth greater than 2 are wrongly placed in the
group described above by BFQ.

This commits fixes this problem by using a different bfq_group pointer in
the update cycle in order to avoid the overwrite of the variable holding
the original group reference.

Reported-by: Kwon Je Oh <kwonje.oh2@gmail.com>
Signed-off-by: Carlo Nonato <carlo.nonato95@gmail.com>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-03-06 07:00:58 -07:00
Daniel Wagner
e959e5405f block: Remove used kblockd_schedule_work_on()
Commit ee63cfa7fc ("block: add kblockd_schedule_work_on()")
introduced the helper in 2016. Remove it because since then no caller
was added.

Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Daniel Wagner <dwagner@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-03-02 07:17:31 -07:00
John Garry
cae740a04b blk-mq: Remove some unused function arguments
The struct blk_mq_hw_ctx pointer argument in blk_mq_put_tag(),
blk_mq_poll_nsecs(), and blk_mq_poll_hybrid_sleep() is unused, so remove
it.

Overall obj code size shows a minor reduction, before:
   text	   data	    bss	    dec	    hex	filename
  27306	   1312	      0	  28618	   6fca	block/blk-mq.o
   4303	    272	      0	   4575	   11df	block/blk-mq-tag.o

after:
  27282	   1312	      0	  28594	   6fb2	block/blk-mq.o
   4311	    272	      0	   4583	   11e7	block/blk-mq-tag.o

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: John Garry <john.garry@huawei.com>
--
This minor patch had been carried as part of the blk-mq shared tags RFC,
I'd rather not carry it anymore as it required rebasing, so now or never..
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-02-26 10:34:41 -07:00
Ming Lei
01e99aeca3 blk-mq: insert passthrough request into hctx->dispatch directly
For some reason, device may be in one situation which can't handle
FS request, so STS_RESOURCE is always returned and the FS request
will be added to hctx->dispatch. However passthrough request may
be required at that time for fixing the problem. If passthrough
request is added to scheduler queue, there isn't any chance for
blk-mq to dispatch it given we prioritize requests in hctx->dispatch.
Then the FS IO request may never be completed, and IO hang is caused.

So passthrough request has to be added to hctx->dispatch directly
for fixing the IO hang.

Fix this issue by inserting passthrough request into hctx->dispatch
directly together withing adding FS request to the tail of
hctx->dispatch in blk_mq_dispatch_rq_list(). Actually we add FS request
to tail of hctx->dispatch at default, see blk_mq_request_bypass_insert().

Then it becomes consistent with original legacy IO request
path, in which passthrough request is always added to q->queue_head.

Cc: Dongli Zhang <dongli.zhang@oracle.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Ewan D. Milne <emilne@redhat.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-02-24 18:50:48 -07:00
Linus Torvalds
ed535f2c9e block-5.6-2020-02-05
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Merge tag 'block-5.6-2020-02-05' of git://git.kernel.dk/linux-block

Pull more block updates from Jens Axboe:
 "Some later arrivals, but all fixes at this point:

   - bcache fix series (Coly)

   - Series of BFQ fixes (Paolo)

   - NVMe pull request from Keith with a few minor NVMe fixes

   - Various little tweaks"

* tag 'block-5.6-2020-02-05' of git://git.kernel.dk/linux-block: (23 commits)
  nvmet: update AEN list and array at one place
  nvmet: Fix controller use after free
  nvmet: Fix error print message at nvmet_install_queue function
  brd: check and limit max_part par
  nvme-pci: remove nvmeq->tags
  nvmet: fix dsm failure when payload does not match sgl descriptor
  nvmet: Pass lockdep expression to RCU lists
  block, bfq: clarify the goal of bfq_split_bfqq()
  block, bfq: get a ref to a group when adding it to a service tree
  block, bfq: remove ifdefs from around gets/puts of bfq groups
  block, bfq: extend incomplete name of field on_st
  block, bfq: get extra ref to prevent a queue from being freed during a group move
  block, bfq: do not insert oom queue into position tree
  block, bfq: do not plug I/O for bfq_queues with no proc refs
  bcache: check return value of prio_read()
  bcache: fix incorrect data type usage in btree_flush_write()
  bcache: add readahead cache policy options via sysfs interface
  bcache: explicity type cast in bset_bkey_last()
  bcache: fix memory corruption in bch_cache_accounting_clear()
  xen/blkfront: limit allocated memory size to actual use case
  ...
2020-02-06 06:15:23 +00:00
Paolo Valente
c92bddee77 block, bfq: clarify the goal of bfq_split_bfqq()
The exact, general goal of the function bfq_split_bfqq() is not that
apparent. Add a comment to make it clear.

Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-02-03 06:58:15 -07:00
Paolo Valente
db37a34c56 block, bfq: get a ref to a group when adding it to a service tree
BFQ schedules generic entities, which may represent either bfq_queues
or groups of bfq_queues. When an entity is inserted into a service
tree, a reference must be taken, to make sure that the entity does not
disappear while still referred in the tree. Unfortunately, such a
reference is mistakenly taken only if the entity represents a
bfq_queue. This commit takes a reference also in case the entity
represents a group.

Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Tested-by: Chris Evich <cevich@redhat.com>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-02-03 06:58:15 -07:00
Paolo Valente
4d8340d0d4 block, bfq: remove ifdefs from around gets/puts of bfq groups
ifdefs around gets and puts of bfq groups reduce readability, remove them.

Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Reported-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-02-03 06:58:15 -07:00
Paolo Valente
33a16a9804 block, bfq: extend incomplete name of field on_st
The flag on_st in the bfq_entity data structure is true if the entity
is on a service tree or is in service. Yet the name of the field,
confusingly, does not mention the second, very important case. Extend
the name to mention the second case too.

Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-02-03 06:58:15 -07:00
Paolo Valente
ecedd3d7e1 block, bfq: get extra ref to prevent a queue from being freed during a group move
In bfq_bfqq_move(), the bfq_queue, say Q, to be moved to a new group
may happen to be deactivated in the scheduling data structures of the
source group (and then activated in the destination group). If Q is
referred only by the data structures in the source group when the
deactivation happens, then Q is freed upon the deactivation.

This commit addresses this issue by getting an extra reference before
the possible deactivation, and releasing this extra reference after Q
has been moved.

Tested-by: Chris Evich <cevich@redhat.com>
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-02-03 06:58:15 -07:00
Paolo Valente
32c59e3a9a block, bfq: do not insert oom queue into position tree
BFQ maintains an ordered list, implemented with an RB tree, of
head-request positions of non-empty bfq_queues. This position tree,
inherited from CFQ, is used to find bfq_queues that contain I/O close
to each other. BFQ merges these bfq_queues into a single shared queue,
if this boosts throughput on the device at hand.

There is however a special-purpose bfq_queue that does not participate
in queue merging, the oom bfq_queue. Yet, also this bfq_queue could be
wrongly added to the position tree. So bfqq_find_close() could return
the oom bfq_queue, which is a source of further troubles in an
out-of-memory situation. This commit prevents the oom bfq_queue from
being inserted into the position tree.

Tested-by: Patrick Dung <patdung100@gmail.com>
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-02-03 06:58:15 -07:00
Paolo Valente
f718b09327 block, bfq: do not plug I/O for bfq_queues with no proc refs
Commit 478de3380c ("block, bfq: deschedule empty bfq_queues not
referred by any process") fixed commit 3726112ec7 ("block, bfq:
re-schedule empty queues if they deserve I/O plugging") by
descheduling an empty bfq_queue when it remains with not process
reference. Yet, this still left a case uncovered: an empty bfq_queue
with not process reference that remains in service. This happens for
an in-service sync bfq_queue that is deemed to deserve I/O-dispatch
plugging when it remains empty. Yet no new requests will arrive for
such a bfq_queue if no process sends requests to it any longer. Even
worse, the bfq_queue may happen to be prematurely freed while still in
service (because there may remain no reference to it any longer).

This commit solves this problem by preventing I/O dispatch from being
plugged for the in-service bfq_queue, if the latter has no process
reference (the bfq_queue is then prevented from remaining in service).

Fixes: 3726112ec7 ("block, bfq: re-schedule empty queues if they deserve I/O plugging")
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Reported-by: Patrick Dung <patdung100@gmail.com>
Tested-by: Patrick Dung <patdung100@gmail.com>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-02-03 06:58:14 -07:00
Linus Torvalds
33c84e89ab SCSI misc on 20200129
This series is slightly unusual because it includes Arnd's compat
 ioctl tree here:
 
 1c46a2cf2d Merge tag 'block-ioctl-cleanup-5.6' into 5.6/scsi-queue
 
 Excluding Arnd's changes, this is mostly an update of the usual
 drivers: megaraid_sas, mpt3sas, qla2xxx, ufs, lpfc, hisi_sas.  There
 are a couple of core and base updates around error propagation and
 atomicity in the attribute container base we use for the SCSI
 transport classes.  The rest is minor changes and updates.
 
 Signed-off-by: James E.J. Bottomley <jejb@linux.ibm.com>
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Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi

Pull SCSI updates from James Bottomley:
 "This series is slightly unusual because it includes Arnd's compat
  ioctl tree here:

    1c46a2cf2d Merge tag 'block-ioctl-cleanup-5.6' into 5.6/scsi-queue

  Excluding Arnd's changes, this is mostly an update of the usual
  drivers: megaraid_sas, mpt3sas, qla2xxx, ufs, lpfc, hisi_sas.

  There are a couple of core and base updates around error propagation
  and atomicity in the attribute container base we use for the SCSI
  transport classes.

  The rest is minor changes and updates"

* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (149 commits)
  scsi: hisi_sas: Rename hisi_sas_cq.pci_irq_mask
  scsi: hisi_sas: Add prints for v3 hw interrupt converge and automatic affinity
  scsi: hisi_sas: Modify the file permissions of trigger_dump to write only
  scsi: hisi_sas: Replace magic number when handle channel interrupt
  scsi: hisi_sas: replace spin_lock_irqsave/spin_unlock_restore with spin_lock/spin_unlock
  scsi: hisi_sas: use threaded irq to process CQ interrupts
  scsi: ufs: Use UFS device indicated maximum LU number
  scsi: ufs: Add max_lu_supported in struct ufs_dev_info
  scsi: ufs: Delete is_init_prefetch from struct ufs_hba
  scsi: ufs: Inline two functions into their callers
  scsi: ufs: Move ufshcd_get_max_pwr_mode() to ufshcd_device_params_init()
  scsi: ufs: Split ufshcd_probe_hba() based on its called flow
  scsi: ufs: Delete struct ufs_dev_desc
  scsi: ufs: Fix ufshcd_probe_hba() reture value in case ufshcd_scsi_add_wlus() fails
  scsi: ufs-mediatek: enable low-power mode for hibern8 state
  scsi: ufs: export some functions for vendor usage
  scsi: ufs-mediatek: add dbg_register_dump implementation
  scsi: qla2xxx: Fix a NULL pointer dereference in an error path
  scsi: qla1280: Make checking for 64bit support consistent
  scsi: megaraid_sas: Update driver version to 07.713.01.00-rc1
  ...
2020-01-29 18:16:16 -08:00
Linus Torvalds
48b4b4ff1e for-5.6/block-2020-01-27
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Merge tag 'for-5.6/block-2020-01-27' of git://git.kernel.dk/linux-block

Pull core block updates from Jens Axboe:
 "This may be the most quiet round we've had in years. I'm not
  complaining. Really not a lot to detail here, outside of spelling and
  documentation improvements/fixes, we have:

   - Allow t10-pi to be modular (Herbert)

   - Remove dead code in bfq (Alex)

   - Mark zone management requests with REQ_SYNC (Chaitanya)

   - BFQ division improvement (Wen)

   - Small series improving plugging (Pavel)"

* tag 'for-5.6/block-2020-01-27' of git://git.kernel.dk/linux-block:
  partitions/ldm: fix spelling mistake "to" -> "too"
  block, bfq: improve arithmetic division in bfq_delta()
  block/bfq: remove unused bfq_class_rt which never used
  block: mark zone-mgmt bios with REQ_SYNC
  blk-mq: Document functions for sending request
  block: Allow t10-pi to be modular
  blk-mq: optimise blk_mq_flush_plug_list()
  list: introduce list_for_each_continue()
  blk-mq: optimise rq sort function
2020-01-27 12:38:25 -08:00
Christoph Hellwig
b72053072c block: allow partitions on host aware zone devices
Host-aware SMR drives can be used with the commands to explicitly manage
zone state, but they can also be used as normal disks.  In the former
case it makes perfect sense to allow partitions on them, in the latter
it does not, just like for host managed devices.  Add a check to
add_partition to allow partitions on host aware devices, but give
up any zone management capabilities in that case, which also catches
the previously missed case of adding a partition vs just scanning it.

Because sd can rescan the attribute at runtime it needs to check if
a disk has partitions, for which a new helper is added to genhd.h.

Fixes: 5eac3eb30c ("block: Remove partition support for zoned block devices")
Reported-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-01-26 09:59:08 -07:00
Colin Ian King
5336da37a5 partitions/ldm: fix spelling mistake "to" -> "too"
There is a spelling mistake in a ldm_error message. Fix it.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-01-23 11:41:45 -07:00
Wen Yang
554d21efb0 block, bfq: improve arithmetic division in bfq_delta()
do_div() does a 64-by-32 division. Use div64_ul() instead of it
if the divisor is unsigned long, to avoid truncation to 32-bit.
And as a nice side effect also cleans up the function a bit.

Signed-off-by: Wen Yang <wenyang@linux.alibaba.com>
Cc: Paolo Valente <paolo.valente@linaro.org>
Cc: Jens Axboe <axboe@fb.com>
Cc: linux-block@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-01-22 10:34:11 -07:00
Alex Shi
b7f22d993f block/bfq: remove unused bfq_class_rt which never used
This macro is never used after introduced from commit aee69d78de
("block, bfq: introduce the BFQ-v0 I/O scheduler as an extra scheduler")

Better to remove it.

Signed-off-by: Alex Shi <alex.shi@linux.alibaba.com>
Cc: Paolo Valente <paolo.valente@linaro.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-01-22 10:31:20 -07:00
Mikulas Patocka
ad6bf88a6c block: fix an integer overflow in logical block size
Logical block size has type unsigned short. That means that it can be at
most 32768. However, there are architectures that can run with 64k pages
(for example arm64) and on these architectures, it may be possible to
create block devices with 64k block size.

For exmaple (run this on an architecture with 64k pages):

Mount will fail with this error because it tries to read the superblock using 2-sector
access:
  device-mapper: writecache: I/O is not aligned, sector 2, size 1024, block size 65536
  EXT4-fs (dm-0): unable to read superblock

This patch changes the logical block size from unsigned short to unsigned
int to avoid the overflow.

Cc: stable@vger.kernel.org
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-01-15 21:43:09 -07:00
Ming Lei
4a2f704eb2 block: fix get_max_segment_size() overflow on 32bit arch
Commit 429120f3df starts to take account of segment's start dma address
when computing max segment size, and data type of 'unsigned long'
is used to do that. However, the segment mask may be 0xffffffff, so
the figured out segment size may be overflowed in case of zero physical
address on 32bit arch.

Fix the issue by returning queue_max_segment_size() directly when that
happens.

Fixes: 429120f3df ("block: fix splitting segments on boundary masks")
Reported-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Cc: Christoph Hellwig <hch@lst.de>
Tested-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-01-14 13:37:40 -07:00
Ming Lei
83c9c54716 fs: move guard_bio_eod() after bio_set_op_attrs
Commit 85a8ce62c2 ("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 <cmaiolino@redhat.com>
Cc: linux-fsdevel@vger.kernel.org
Fixes: 85a8ce62c2 ("block: add bio_truncate to fix guard_bio_eod")
Signed-off-by: Ming Lei <ming.lei@redhat.com>

Fold in kerneldoc and bio_op() change.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-01-09 08:16:12 -07:00
Chaitanya Kulkarni
8e42d239cb block: mark zone-mgmt bios with REQ_SYNC
In the current implementation, final zone-mgmt request is issued with
submit_bio_wait() which marks the bio REQ_SYNC. This is needed since
immediate action is expected for zone-mgmt requests as these are
blocking operations. This also bypasses the scheduler in the
blk_mq_make_request() and dispatches the request directly into the
hw ctx.

This patch marks all the chained bios REQ_SYNC so that we can have
above-mentioned behavior for non-final bios also.

Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Bob Liu <bob.liu@oracle.com>
Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-01-09 07:59:12 -07:00
André Almeida
105663f73e blk-mq: Document functions for sending request
Add or improve documentation for function regarding creating and sending
IO requests to the hardware.

Signed-off-by: André Almeida <andrealmeid@collabora.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-01-06 21:00:27 -07:00
Herbert Xu
a754bd5f18 block: Allow t10-pi to be modular
Currently t10-pi can only be built into the block layer which via
crc-t10dif pulls in a whole chunk of the Crypto API.  In fact all
users of t10-pi work as modules and there is no reason for it to
always be built-in.

This patch adds a new hidden option for t10-pi that is selected
automatically based on BLK_DEV_INTEGRITY and whether the users
of t10-pi are built-in or not.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-01-06 20:59:04 -07:00
Arnd Bergmann
9b81648cb5 compat_ioctl: simplify up block/ioctl.c
Having separate implementations of blkdev_ioctl() often leads to these
getting out of sync, despite the comment at the top.

Since most of the ioctl commands are compatible, and we try very hard
not to add any new incompatible ones, move all the common bits into a
shared function and leave only the ones that are historically different
in separate functions for native/compat mode.

To deal with the compat_ptr() conversion, pass both the integer
argument and the pointer argument into the new blkdev_common_ioctl()
and make sure to always use the correct one of these.

blkdev_ioctl() is now only kept as a separate exported interfact
for drivers/char/raw.c, which lacks a compat_ioctl variant.
We should probably either move raw.c to staging if there are no
more users, or export blkdev_compat_ioctl() as well.

Reviewed-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2020-01-03 09:42:52 +01:00
Arnd Bergmann
5fb889f587 compat_ioctl: block: simplify compat_blkpg_ioctl()
There is no need to go through a compat_alloc_user_space()
copy any more, just wrap the function in a small helper that
works the same way for native and compat mode.

Reviewed-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2020-01-03 09:42:52 +01:00
Arnd Bergmann
bdc1ddad3e compat_ioctl: block: move blkdev_compat_ioctl() into ioctl.c
Having both in the same file allows a number of simplifications
to the compat path, and makes it more likely that changes to
the native path get applied to the compat version as well.

Reviewed-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2020-01-03 09:42:52 +01:00
Arnd Bergmann
1df23c6fe5 compat_ioctl: move HDIO ioctl handling into drivers/ide
Most of the HDIO ioctls are only used by the obsolete drivers/ide
subsystem, these can be handled by changing ide_cmd_ioctl() to be aware
of compat mode and doing the correct transformations in place and using
it as both native and compat handlers for all drivers.

The SCSI drivers implementing the same commands are already doing
this in the drivers, so the compat_blkdev_driver_ioctl() function
is no longer needed now.

The BLKSECTSET and HDIO_GETGEO_BIG ioctls are not implemented
in any driver any more and no longer need any conversion.

Reviewed-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2020-01-03 09:42:52 +01:00
Arnd Bergmann
64cbfa9655 compat_ioctl: move cdrom commands into cdrom.c
There is no need for the special cases for the cdrom ioctls any more now,
so make sure that each cdrom driver has a .compat_ioctl() callback and
calls cdrom_compat_ioctl() directly there.

Reviewed-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2020-01-03 09:42:52 +01:00
Arnd Bergmann
fe0da4e5e8 compat_ioctl: bsg: add handler
bsg_ioctl() calls into scsi_cmd_ioctl() for a couple of generic commands
and relies on fs/compat_ioctl.c to handle it correctly in compat mode.

Adding a private compat_ioctl() handler avoids that round-trip and lets
us get rid of the generic emulation once this is done.

Note that bsg implements an SG_IO command that is different from the
other drivers and does not need emulation.

Reviewed-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2020-01-03 09:33:21 +01:00
Arnd Bergmann
8f8f562038 compat_ioctl: move CDROMREADADIO to cdrom.c
Again, there is only one file that needs this, so move the conversion
handler into the native implementation.

Reviewed-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2020-01-03 09:33:08 +01:00
Arnd Bergmann
f3ee6e63a9 compat_ioctl: move CDROM_SEND_PACKET handling into scsi
There is only one implementation of this ioctl, so move the handling out
of the common block layer code into the place where it's actually needed.

It also gets called indirectly through pktcdvd, which needs to be aware
of this change.

As I noticed, the old implementation of the compat handler failed to
convert the structure on the way out, so the updated fields never got
written back to user space. This is either not important, or it has
never worked and should be fixed now.

Reviewed-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2020-01-03 09:33:05 +01:00
Arnd Bergmann
ee6a129dff compat_ioctl: block: add blkdev_compat_ptr_ioctl
A lot of block drivers need only a trivial .compat_ioctl callback.

Add a helper function that can be set as the callback pointer
to only convert the argument using the compat_ptr() conversion
and otherwise assume all input and output data is compatible,
or handled using in_compat_syscall() checks.

This mirrors the compat_ptr_ioctl() helper function used in
character devices.

Reviewed-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2020-01-03 09:32:59 +01:00
Arnd Bergmann
78ed001d9e compat: scsi: sg: fix v3 compat read/write interface
In the v5.4 merge window, a cleanup patch from Al Viro conflicted
with my rework of the compat handling for sg.c read(). Linus Torvalds
did a correct merge but pointed out that the resulting code is still
unsatisfactory.

I later noticed that the sg_new_read() function still gets the compat
mode wrong, when the 'count' argument is large enough to pass a
compat_sg_io_hdr object, but not a nativ sg_io_hdr.

To address both of these, move the definition of compat_sg_io_hdr
into a scsi/sg.h to make it visible to sg.c and rewrite the logic
for reading req_pack_id as well as the size check to a simpler
version that gets the expected results.

Fixes: c35a5cfb41 ("scsi: sg: sg_read(): simplify reading ->pack_id of userland sg_io_hdr_t")
Fixes: 98aaaec4a1 ("compat_ioctl: reimplement SG_IO handling")
Reviewed-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2020-01-03 09:32:54 +01:00
Ming Lei
429120f3df block: fix splitting segments on boundary masks
We ran into a problem with a mpt3sas based controller, where we would
see random (and hard to reproduce) file corruption). The issue seemed
specific to this controller, but wasn't specific to the file system.
After a lot of debugging, we find out that it's caused by segments
spanning a 4G memory boundary. This shouldn't happen, as the default
setting for segment boundary masks is 4G.

Turns out there are two issues in get_max_segment_size():

1) The default segment boundary mask is bypassed

2) The segment start address isn't taken into account when checking
   segment boundary limit

Fix these two issues by removing the bypass of the segment boundary
check even if the mask is set to the default value, and taking into
account the actual start address of the request when checking if a
segment needs splitting.

Cc: stable@vger.kernel.org # v5.1+
Reviewed-by: Chris Mason <clm@fb.com>
Tested-by: Chris Mason <clm@fb.com>
Fixes: dcebd75592 ("block: use bio_for_each_bvec() to compute multi-page bvec count")
Signed-off-by: Ming Lei <ming.lei@redhat.com>

Dropped const on the page pointer, ppc page_to_phys() doesn't mark the
page as const...

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-12-30 08:51:18 -07:00
Ming Lei
85a8ce62c2 block: add bio_truncate to fix guard_bio_eod
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 dce30ca9e3 ("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 <cmaiolino@redhat.com>
Cc: linux-fsdevel@vger.kernel.org
Fixed-by: dce30ca9e3 ("fs: fix guard_bio_eod to check for real EOD errors")
Reported-by: syzbot+2b9e54155c8c25d8d165@syzkaller.appspotmail.com
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-12-28 09:44:56 -07:00