Commit Graph

723183 Commits

Author SHA1 Message Date
Coly Li
2831231d4c bcache: reduce cache_set devices iteration by devices_max_used
Member devices of struct cache_set is used to reference all attached
bcache devices to this cache set. If it is treated as array of pointers,
size of devices[] is indicated by member nr_uuids of struct cache_set.

nr_uuids is calculated in drivers/md/super.c:bch_cache_set_alloc(),
	bucket_bytes(c) / sizeof(struct uuid_entry)
Bucket size is determined by user space tool "make-bcache", by default it
is 1024 sectors (defined in bcache-tools/make-bcache.c:main()). So default
nr_uuids value is 4096 from the above calculation.

Every time when bcache code iterates bcache devices of a cache set, all
the 4096 pointers are checked even only 1 bcache device is attached to the
cache set, that's a wast of time and unncessary.

This patch adds a member devices_max_used to struct cache_set. Its value
is 1 + the maximum used index of devices[] in a cache set. When iterating
all valid bcache devices of a cache set, use c->devices_max_used in
for-loop may reduce a lot of useless checking.

Personally, my motivation of this patch is not for performance, I use it
in bcache debugging, which helps me to narrow down the scape to check
valid bcached devices of a cache set.

Signed-off-by: Coly Li <colyli@suse.de>
Reviewed-by: Michael Lyle <mlyle@lyle.org>
Reviewed-by: Tang Junhui <tang.junhui@zte.com.cn>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-01-08 13:29:00 -07:00
Zhai Zhaoxuan
b40503ea4f bcache: fix unmatched generic_end_io_acct() & generic_start_io_acct()
The function cached_dev_make_request() and flash_dev_make_request() call
generic_start_io_acct() with (struct bcache_device)->disk when they start a
closure. Then the function bio_complete() calls generic_end_io_acct() with
(struct search)->orig_bio->bi_disk when the closure has done.
Since the `bi_disk` is not the bcache device, the generic_end_io_acct() is
called with a wrong device queue.

It causes the "inflight" (in struct hd_struct) counter keep increasing
without decreasing.

This patch fix the problem by calling generic_end_io_acct() with
(struct bcache_device)->disk.

Signed-off-by: Zhai Zhaoxuan <kxuanobj@gmail.com>
Reviewed-by: Michael Lyle <mlyle@lyle.org>
Reviewed-by: Coly Li <colyli@suse.de>
Reviewed-by: Tang Junhui <tang.junhui@zte.com.cn>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-01-08 13:29:00 -07:00
Kent Overstreet
ce439bf78b bcache: mark closure_sync() __sched
[edit by mlyle: include sched/debug.h to get __sched]

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Michael Lyle <mlyle@lyle.org>
Reviewed-by: Michael Lyle <mlyle@lyle.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-01-08 13:29:00 -07:00
Kent Overstreet
e4bf791937 bcache: Fix, improve efficiency of closure_sync()
Eliminates cases where sync can race and fail to complete / get stuck.
Removes many status flags and simplifies entering-and-exiting closure
sleeping behaviors.

[mlyle: fixed conflicts due to changed return behavior in mainline.
extended commit comment, and squashed down two commits that were mostly
contradictory to get to this state.  Changed __set_current_state to
set_current_state per Jens review comment]

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Michael Lyle <mlyle@lyle.org>
Reviewed-by: Michael Lyle <mlyle@lyle.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-01-08 13:29:00 -07:00
Michael Lyle
b1092c9af9 bcache: allow quick writeback when backing idle
If the control system would wait for at least half a second, and there's
been no reqs hitting the backing disk for awhile: use an alternate mode
where we have at most one contiguous set of writebacks in flight at a
time. (But don't otherwise delay).  If front-end IO appears, it will
still be quick, as it will only have to contend with one real operation
in flight.  But otherwise, we'll be sending data to the backing disk as
quickly as it can accept it (with one op at a time).

Signed-off-by: Michael Lyle <mlyle@lyle.org>
Reviewed-by: Tang Junhui <tang.junhui@zte.com.cn>
Acked-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-01-08 13:29:00 -07:00
Michael Lyle
6e6ccc67b9 bcache: writeback: properly order backing device IO
Writeback keys are presently iterated and dispatched for writeback in
order of the logical block address on the backing device.  Multiple may
be, in parallel, read from the cache device and then written back
(especially when there are contiguous I/O).

However-- there was no guarantee with the existing code that the writes
would be issued in LBA order, as the reads from the cache device are
often re-ordered.  In turn, when writing back quickly, the backing disk
often has to seek backwards-- this slows writeback and increases
utilization.

This patch introduces an ordering mechanism that guarantees that the
original order of issue is maintained for the write portion of the I/O.
Performance for writeback is significantly improved when there are
multiple contiguous keys or high writeback rates.

Signed-off-by: Michael Lyle <mlyle@lyle.org>
Reviewed-by: Tang Junhui <tang.junhui@zte.com.cn>
Tested-by: Tang Junhui <tang.junhui@zte.com.cn>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-01-08 13:29:00 -07:00
Tang Junhui
539d39eb27 bcache: fix wrong return value in bch_debug_init()
in bch_debug_init(), ret is always 0, and the return value is useless,
change it to return 0 if be success after calling debugfs_create_dir(),
else return a non-zero value.

Signed-off-by: Tang Junhui <tang.junhui@zte.com.cn>
Reviewed-by: Michael Lyle <mlyle@lyle.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-01-08 13:29:00 -07:00
Tang Junhui
4eca1cb28d bcache: segregate flash only volume write streams
In such scenario that there are some flash only volumes
, and some cached devices, when many tasks request these devices in
writeback mode, the write IOs may fall to the same bucket as bellow:
| cached data | flash data | cached data | cached data| flash data|
then after writeback of these cached devices, the bucket would
be like bellow bucket:
| free | flash data | free | free | flash data |

So, there are many free space in this bucket, but since data of flash
only volumes still exists, so this bucket cannot be reclaimable,
which would cause waste of bucket space.

In this patch, we segregate flash only volume write streams from
cached devices, so data from flash only volumes and cached devices
can store in different buckets.

Compare to v1 patch, this patch do not add a additionally open bucket
list, and it is try best to segregate flash only volume write streams
from cached devices, sectors of flash only volumes may still be mixed
with dirty sectors of cached device, but the number is very small.

[mlyle: fixed commit log formatting, permissions, line endings]

Signed-off-by: Tang Junhui <tang.junhui@zte.com.cn>
Reviewed-by: Michael Lyle <mlyle@lyle.org>
Signed-off-by: Michael Lyle <mlyle@lyle.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-01-08 13:29:00 -07:00
Vasyl Gomonovych
9d13411784 bcache: Use PTR_ERR_OR_ZERO()
Fix ptr_ret.cocci warnings:
drivers/md/bcache/btree.c:1800:1-3: WARNING: PTR_ERR_OR_ZERO can be used

Use PTR_ERR_OR_ZERO rather than if(IS_ERR(...)) + PTR_ERR

Generated by: scripts/coccinelle/api/ptr_ret.cocci

Signed-off-by: Vasyl Gomonovych <gomonovych@gmail.com>
Reviewed-by: Michael Lyle <mlyle@lyle.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-01-08 13:29:00 -07:00
Tang Junhui
8d29c4426b bcache: stop writeback thread after detaching
Currently, when a cached device detaching from cache, writeback thread is
not stopped, and writeback_rate_update work is not canceled. For example,
after the following command:
echo 1 >/sys/block/sdb/bcache/detach
you can still see the writeback thread. Then you attach the device to the
cache again, bcache will create another writeback thread, for example,
after below command:
echo  ba0fb5cd-658a-4533-9806-6ce166d883b9 > /sys/block/sdb/bcache/attach
then you will see 2 writeback threads.
This patch stops writeback thread and cancels writeback_rate_update work
when cached device detaching from cache.

Compare with patch v1, this v2 patch moves code down into the register
lock for safety in case of any future changes as Coly and Mike suggested.

[edit by mlyle: commit log spelling/formatting]

Signed-off-by: Tang Junhui <tang.junhui@zte.com.cn>
Reviewed-by: Michael Lyle <mlyle@lyle.org>
Signed-off-by: Michael Lyle <mlyle@lyle.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-01-08 13:29:00 -07:00
Rui Hua
b221fc130c bcache: ret IOERR when read meets metadata error
The read request might meet error when searching the btree, but the error
was not handled in cache_lookup(), and this kind of metadata failure will
not go into cached_dev_read_error(), finally, the upper layer will receive
bi_status=0.  In this patch we judge the metadata error by the return
value of bch_btree_map_keys(), there are two potential paths give rise to
the error:

1. Because the btree is not totally cached in memery, we maybe get error
   when read btree node from cache device (see bch_btree_node_get()), the
   likely errno is -EIO, -ENOMEM

2. When read miss happens, bch_btree_insert_check_key() will be called to
   insert a "replace_key" to btree(see cached_dev_cache_miss(), just for
   doing preparatory work before insert the missed data to cache device),
   a failure can also happen in this situation, the likely errno is
   -ENOMEM

bch_btree_map_keys() will return MAP_DONE in normal scenario, but we will
get either -EIO or -ENOMEM in above two cases. if this happened, we should
NOT recover data from backing device (when cache device is dirty) because
we don't know whether bkeys the read request covered are all clean.  And
after that happened, s->iop.status is still its initially value(0) before
we submit s->bio.bio, we set it to BLK_STS_IOERR, so it can go into
cached_dev_read_error(), and finally it can be passed to upper layer, or
recovered by reread from backing device.

[edit by mlyle: patch formatting, word-wrap, comment spelling,
commit log format]

Signed-off-by: Hua Rui <huarui.dev@gmail.com>
Reviewed-by: Michael Lyle <mlyle@lyle.org>
Signed-off-by: Michael Lyle <mlyle@lyle.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-01-08 13:29:00 -07:00
Jens Axboe
550203e64c Merge branch 'nvme-4.16' of git://git.infradead.org/nvme into for-4.16/block
Pull NVMe fixes from Christoph:

"Below are the pending nvme updates for Linux 4.16. Just fixes and
 cleanups from various contributors this time around."
2018-01-08 12:19:41 -07:00
Israel Rukshin
b837b28394 nvme: fix subsystem multiple controllers support check
There is a problem when another module (e.g. nvmet) takes a reference on
the nvme block device and the physical nvme drive is removed.  In that
case nvme_free_ctrl() will not be called and the controller state will be
"deleting" or "dead" unless nvmet module releases the block device.
Later on, the same nvme drive probes back and nvme_init_subsystem() will
be called and fail due to duplicate subnqn (if the nvme device doesn't
support subsystem with multiple controllers). This will cause a probe
failure.  This commit changes the check of multiple controllers support
at nvme_init_subsystem() by not counting all the controllers at "dead" or
"deleting" state (this is safe because controllers at this state will
never be active again).

Fixes: ab9e00cc72 ("nvme: track subsystems")
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Signed-off-by: Israel Rukshin <israelr@mellanox.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-01-08 16:57:00 +01:00
Nitzan Carmi
85088c4a0f nvme: take refcount on transport module
The block device is backed by the transport so we must ensure that the
transport driver will not be removed until all references are released.
Otherwise, we might end up referencing freed memory.

Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Signed-off-by: Nitzan Carmi <nitzanc@mellanox.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-01-08 16:56:57 +01:00
Jianchao Wang
2b1b7e784a nvme-pci: fix NULL pointer reference in nvme_alloc_ns
When the io queues setup or tagset allocation failed, ctrl.tagset is
NULL.  But the scan work will still be queued and executed, then panic
comes up due to NULL pointer reference of ctrl.tagset.

To fix this, add a new ctrl state NVME_CTRL_ADMIN_ONLY to inidcate only
admin queue is live. When non io queues or tagset allocation failed, ctrl
enters into this state, scan work will not be started.  But async event
work and nvme dev ioctl will be still available.  This will be helpful to
do further investigation and recovery.

Suggested-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jianchao Wang <jianchao.w.wang@oracle.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-01-08 11:02:13 +01:00
Max Gurtovoy
1a3838d732 nvme: modify the debug level for setting shutdown timeout
When an NVMe controller reports RTD3 Entry Latency larger than the value
of shutdown_timeout module parameter, we update the shutdown_timeout
accordingly to honor RTD3 Entry Latency. Use an informational debug level
instead of a warning level for it.

Signed-off-by: Max Gurtovoy <maxg@mellanox.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-01-08 11:02:00 +01:00
Sagi Grimberg
4caff8fc19 nvme-pci: don't open-code nvme_reset_ctrl
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-01-08 11:01:59 +01:00
Israel Rukshin
6b1943af3f nvmet: rearrange nvmet_ctrl_free()
Make it symmetric to nvmet_alloc_ctrl().

Signed-off-by: Israel Rukshin <israelr@mellanox.com>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-01-08 11:01:59 +01:00
Israel Rukshin
eca19dc1d8 nvmet: fix error flow in nvmet_alloc_ctrl()
Remove the allocated id on error.

Signed-off-by: Israel Rukshin <israelr@mellanox.com>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-01-08 11:01:58 +01:00
Minwoo Im
6fbcde6691 nvme-pci: remove an unnecessary initialization in HMB code
The local variable __size__ will be set a bit later in a for-loop.
Remove the explicit initialization at the beginning of this function.

Signed-off-by: Minwoo Im <minwoo.im.dev@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-01-08 11:01:57 +01:00
Roy Shterman
0de5cd367c nvme-fabrics: protect against module unload during create_ctrl
NVMe transport driver module unload may (and usually does) trigger
iteration over the active controllers and delete them all (sometimes
under a mutex).  However, a controller can be created concurrently with
module unload which can lead to leakage of resources (most important char
device node leakage) in case the controller creation occured after the
unload delete and drain sequence.  To protect against this, we take a
module reference to guarantee that the nvme transport driver is not
unloaded while creating a controller.

Signed-off-by: Roy Shterman <roys@lightbitslabs.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-01-08 11:01:56 +01:00
James Smart
9ce1f2e12e nvmet-fc: cleanup nvmet add_port/remove_port
The current fc transport add_port routine validates that there is a
matching port to the target port config. It then takes a reference
on the targetport. The del_port removes the reference.

Unfortunately, if the LLDD undergoes a hw reset or driver unload and
wants to unreg the targetport, due to the reference, the targetport
effectively can't be removed. It requires the admin to remove the
port from the nvmet config first, which calls the del_port.
Note: it appears nvmetcli clear skips over the del_port call (I'm
not attempting to change that).

There's no real reason to take the reference. With FC, there is nothing
to enable or disable as the presence of the FC targetport implicitly
means its enabled, and removal of the targtport means its disabled.

Change add_port to simply validate and change remove_port to a noop.
No references are taken on the targetport.

Signed-off-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-01-08 11:01:56 +01:00
James Smart
b6f807738b nvme_fcloop: refactor host/target io job access
The split between what the host accesses on its flows vs what the
target side accesses was flawed. Abort handling didn't properly
clear initiator vs target structure cross-reference and locks
weren't used for synchronization. Thus, there were issues of
freeing structures too soon and access after free.

A couple of these existed pre the IN_ISR mods, but when the
target upcalls were converted to work items, thus adding delays
between the 2 sides of accesses, the problems became pronounced.

Resolve by:
- tracking io state mainly in the tgt-side io structure.
- make the tgt-side io structure released by reference not by
  code flow.
- when changing initiator structures, use locks for
  synchronization
- aborts are clearly tracked for which side saw the abort, and
  after seeing the abort, cross-references are cleared under lock.

Signed-off-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-01-08 11:01:55 +01:00
James Smart
24431d60d3 nvme_fcloop: rework to remove xxx_IN_ISR feature flags
The existing fcloop driver expects the target side upcalls to
the transport to context switch, thus the calls into the nvmet layer
are not done in the calling context of the host/initiator down calls.
The xxx_IN_ISR feature flags are used to select this logic.

The xxx_IN_ISR feature flags should go away in the nvmet_fc transport
as no other lldd utilizes them. Both Broadcom and Cavium lldds have their
own non-ISR deferred handlers thus the nvmet calls can be made directly.

This patch converts the paths that make the target upcalls (command
receive, abort receive) such that they schedule a work item rather
than expecting the transport to schedule the work item.

The patch also cleans up the following:
- The completion path from target to host scheduled a host work
  element called "work". Rename it "tio_done_work" for code clarity.
- The abort io path called a iniwork item to call the host side
  io done. This is no longer needed as the abort routine can make
  the same call.

Signed-off-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-01-08 11:01:54 +01:00
James Smart
6fda20283e nvme_fcloop: disassocate local port structs
The current fcloop driver gets its lport structure from the private
area co-allocated with the fc_localport. All is fine except the
teardown path, which wants to wait on the completion, which is marked
complete by the delete_localport callback performed after
unregister_localport.  The issue is, the nvme_fc transport frees the
localport structure immediately after delete_localport is called,
meaning the original routine is trying to wait on a complete that
was just freed.

Change such that a lport struct is allocated coincident with the
addition and registration of a localport. The private area of the
localport now contains just a backpointer to the real lport struct.
Now, the completion can be waited for, and after completing, the
new structure can be kfree'd.

Signed-off-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-01-08 11:01:54 +01:00
James Smart
278e096063 nvme_fcloop: fix abort race condition
A test case revealed a race condition of an i/o completing on a thread
parallel to the delete_association generating the aborts for the
outstanding ios on the controller.  The i/o completion was freeing the
target fcloop context, thus the abort task referenced the just-freed
memory.

Correct by clearing the target/initiator cross pointers in the io
completion and abort tasks before calling the callbacks. On aborts
that detect already finished io's, ensure the complete context is
called.

Signed-off-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-01-08 11:01:53 +01:00
Sagi Grimberg
6a1c57acab nvmet: lower log level for each queue creation
It is a bit chatty to report on each queue, log it only for debug
purposes.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-01-08 11:01:52 +01:00
Sagi Grimberg
424125a09d nvmet-rdma: lowering log level for chatty debug messages
It is a bit chatty to report on every deleted queue, so keep it for debug
purposes only.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-01-08 11:01:52 +01:00
Sagi Grimberg
cb4876e8ce nvmet-rdma: removed queue cleanup from module exit
We already do that when we are notified in device removal
which is triggered when unregistering as an ib client.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-01-08 11:01:51 +01:00
Ming Lei
fb350e0ad9 blk-mq: fix race between updating nr_hw_queues and switching io sched
In both elevator_switch_mq() and blk_mq_update_nr_hw_queues(), sched tags
can be allocated, and q->nr_hw_queue is used, and race is inevitable, for
example: blk_mq_init_sched() may trigger use-after-free on hctx, which is
freed in blk_mq_realloc_hw_ctxs() when nr_hw_queues is decreased.

This patch fixes the race be holding q->sysfs_lock.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reported-by: Yi Zhang <yi.zhang@redhat.com>
Tested-by: Yi Zhang <yi.zhang@redhat.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-01-06 09:25:36 -07:00
Ming Lei
7d4901a90d blk-mq: avoid to map CPU into stale hw queue
blk_mq_pci_map_queues() may not map one CPU into any hw queue, but its
previous map isn't cleared yet, and may point to one stale hw queue
index.

This patch fixes the following issue by clearing the mapping table before
setting it up in blk_mq_pci_map_queues().

This patches fixes this following issue reported by Zhang Yi:

[  101.202734] BUG: unable to handle kernel NULL pointer dereference at 0000000094d3013f
[  101.211487] IP: blk_mq_map_swqueue+0xbc/0x200
[  101.216346] PGD 0 P4D 0
[  101.219171] Oops: 0000 [#1] SMP
[  101.222674] Modules linked in: sunrpc ipmi_ssif vfat fat intel_rapl sb_edac x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel kvm irqbypass crct10dif_pclmul crc32_pclmul ghash_clmulni_intel intel_cstate intel_uncore mxm_wmi intel_rapl_perf iTCO_wdt ipmi_si ipmi_devintf pcspkr iTCO_vendor_support sg dcdbas ipmi_msghandler wmi mei_me lpc_ich shpchp mei acpi_power_meter dm_multipath ip_tables xfs libcrc32c sd_mod mgag200 i2c_algo_bit drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops ttm drm ahci libahci crc32c_intel libata tg3 nvme nvme_core megaraid_sas ptp i2c_core pps_core dm_mirror dm_region_hash dm_log dm_mod
[  101.284881] CPU: 0 PID: 504 Comm: kworker/u25:5 Not tainted 4.15.0-rc2 #1
[  101.292455] Hardware name: Dell Inc. PowerEdge R730xd/072T6D, BIOS 2.5.5 08/16/2017
[  101.301001] Workqueue: nvme-wq nvme_reset_work [nvme]
[  101.306636] task: 00000000f2c53190 task.stack: 000000002da874f9
[  101.313241] RIP: 0010:blk_mq_map_swqueue+0xbc/0x200
[  101.318681] RSP: 0018:ffffc9000234fd70 EFLAGS: 00010282
[  101.324511] RAX: ffff88047ffc9480 RBX: ffff88047e130850 RCX: 0000000000000000
[  101.332471] RDX: ffffe8ffffd40580 RSI: ffff88047e509b40 RDI: ffff88046f37a008
[  101.340432] RBP: 000000000000000b R08: ffff88046f37a008 R09: 0000000011f94280
[  101.348392] R10: ffff88047ffd4d00 R11: 0000000000000000 R12: ffff88046f37a008
[  101.356353] R13: ffff88047e130f38 R14: 000000000000000b R15: ffff88046f37a558
[  101.364314] FS:  0000000000000000(0000) GS:ffff880277c00000(0000) knlGS:0000000000000000
[  101.373342] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  101.379753] CR2: 0000000000000098 CR3: 000000047f409004 CR4: 00000000001606f0
[  101.387714] Call Trace:
[  101.390445]  blk_mq_update_nr_hw_queues+0xbf/0x130
[  101.395791]  nvme_reset_work+0x6f4/0xc06 [nvme]
[  101.400848]  ? pick_next_task_fair+0x290/0x5f0
[  101.405807]  ? __switch_to+0x1f5/0x430
[  101.409988]  ? put_prev_entity+0x2f/0xd0
[  101.414365]  process_one_work+0x141/0x340
[  101.418836]  worker_thread+0x47/0x3e0
[  101.422921]  kthread+0xf5/0x130
[  101.426424]  ? rescuer_thread+0x380/0x380
[  101.430896]  ? kthread_associate_blkcg+0x90/0x90
[  101.436048]  ret_from_fork+0x1f/0x30
[  101.440034] Code: 48 83 3c ca 00 0f 84 2b 01 00 00 48 63 cd 48 8b 93 10 01 00 00 8b 0c 88 48 8b 83 20 01 00 00 4a 03 14 f5 60 04 af 81 48 8b 0c c8 <48> 8b 81 98 00 00 00 f0 4c 0f ab 30 8b 81 f8 00 00 00 89 42 44
[  101.461116] RIP: blk_mq_map_swqueue+0xbc/0x200 RSP: ffffc9000234fd70
[  101.468205] CR2: 0000000000000098
[  101.471907] ---[ end trace 5fe710f98228a3ca ]---
[  101.482489] Kernel panic - not syncing: Fatal exception
[  101.488505] Kernel Offset: disabled
[  101.497752] ---[ end Kernel panic - not syncing: Fatal exception

Reviewed-by: Christoph Hellwig <hch@lst.de>
Suggested-by: Christoph Hellwig <hch@lst.de>
Reported-by: Yi Zhang <yi.zhang@redhat.com>
Tested-by: Yi Zhang <yi.zhang@redhat.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-01-06 09:25:36 -07:00
Ming Lei
24f5a90f0d blk-mq: quiesce queue during switching io sched and updating nr_requests
Dispatch may still be in-progress after queue is frozen, so we have to
quiesce queue before switching IO scheduler and updating nr_requests.

Also when switching io schedulers, blk_mq_run_hw_queue() may still be
called somewhere(such as from nvme_reset_work()), and io scheduler's
per-hctx data may not be setup yet, so cause oops even inside
blk_mq_hctx_has_pending(), such as it can be run just between:

        ret = e->ops.mq.init_sched(q, e);
AND
        ret = e->ops.mq.init_hctx(hctx, i)

inside blk_mq_init_sched().

This reverts commit 7a148c2fcff8330(block: don't call blk_mq_quiesce_queue()
after queue is frozen) basically, and makes sure blk_mq_hctx_has_pending
won't be called if queue is quiesced.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Fixes: 7a148c2fcff83309(block: don't call blk_mq_quiesce_queue() after queue is frozen)
Reported-by: Yi Zhang <yi.zhang@redhat.com>
Tested-by: Yi Zhang <yi.zhang@redhat.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-01-06 09:25:36 -07:00
Ming Lei
c2856ae2f3 blk-mq: quiesce queue before freeing queue
After queue is frozen, dispatch still may happen, for example:

1) requests are submitted from several contexts
2) requests from all these contexts are inserted to queue, but may dispatch
to LLD in one of these paths, but other paths sill need to move on even all
these requests are completed(that means blk_mq_freeze_queue_wait() returns
at that time)
3) dispatch after queue freezing still moves on and causes use-after-free,
because request queue is freed

This patch quiesces queue after it is frozen, and makes sure all
in-progress dispatch are completed.

This patch fixes the following kernel crash when running heavy IOs vs.
deleting device:

[   36.719251] BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
[   36.720318] IP: kyber_has_work+0x14/0x40
[   36.720847] PGD 254bf5067 P4D 254bf5067 PUD 255e6a067 PMD 0
[   36.721584] Oops: 0000 [#1] PREEMPT SMP
[   36.722105] Dumping ftrace buffer:
[   36.722570]    (ftrace buffer empty)
[   36.723057] Modules linked in: scsi_debug ebtable_filter ebtables ip6table_filter ip6_tables tcm_loop iscsi_target_mod target_core_file target_core_iblock target_core_pscsi target_core_mod xt_CHECKSUM iptable_mangle ipt_MASQUERADE nf_nat_masquerade_ipv4 iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 nf_nat nf_conntrack libcrc32c bridge stp llc fuse iptable_filter ip_tables sd_mod sg btrfs xor zstd_decompress zstd_compress xxhash raid6_pq mptsas mptscsih bcache crc32c_intel ahci mptbase libahci serio_raw scsi_transport_sas nvme libata shpchp lpc_ich virtio_scsi nvme_core binfmt_misc dm_mod iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi null_blk configs
[   36.733438] CPU: 2 PID: 2374 Comm: fio Not tainted 4.15.0-rc2.blk_mq_quiesce+ #714
[   36.735143] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.9.3-1.fc25 04/01/2014
[   36.736688] RIP: 0010:kyber_has_work+0x14/0x40
[   36.737515] RSP: 0018:ffffc9000209bca0 EFLAGS: 00010202
[   36.738431] RAX: 0000000000000008 RBX: ffff88025578bfc8 RCX: ffff880257bf4ed0
[   36.739581] RDX: 0000000000000038 RSI: ffffffff81a98c6d RDI: ffff88025578bfc8
[   36.740730] RBP: ffff880253cebfc8 R08: ffffc9000209bda0 R09: ffff8802554f3480
[   36.741885] R10: ffffc9000209be60 R11: ffff880263f72538 R12: ffff88025573e9e8
[   36.743036] R13: ffff88025578bfd0 R14: 0000000000000001 R15: 0000000000000000
[   36.744189] FS:  00007f9b9bee67c0(0000) GS:ffff88027fc80000(0000) knlGS:0000000000000000
[   36.746617] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   36.748483] CR2: 0000000000000008 CR3: 0000000254bf4001 CR4: 00000000003606e0
[   36.750164] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   36.751455] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   36.752796] Call Trace:
[   36.753992]  blk_mq_do_dispatch_sched+0x7f/0xe0
[   36.755110]  blk_mq_sched_dispatch_requests+0x119/0x190
[   36.756179]  __blk_mq_run_hw_queue+0x83/0x90
[   36.757144]  __blk_mq_delay_run_hw_queue+0xaf/0x110
[   36.758046]  blk_mq_run_hw_queue+0x24/0x70
[   36.758845]  blk_mq_flush_plug_list+0x1e7/0x270
[   36.759676]  blk_flush_plug_list+0xd6/0x240
[   36.760463]  blk_finish_plug+0x27/0x40
[   36.761195]  do_io_submit+0x19b/0x780
[   36.761921]  ? entry_SYSCALL_64_fastpath+0x1a/0x7d
[   36.762788]  entry_SYSCALL_64_fastpath+0x1a/0x7d
[   36.763639] RIP: 0033:0x7f9b9699f697
[   36.764352] RSP: 002b:00007ffc10f991b8 EFLAGS: 00000206 ORIG_RAX: 00000000000000d1
[   36.765773] RAX: ffffffffffffffda RBX: 00000000008f6f00 RCX: 00007f9b9699f697
[   36.766965] RDX: 0000000000a5e6c0 RSI: 0000000000000001 RDI: 00007f9b8462a000
[   36.768377] RBP: 0000000000000000 R08: 0000000000000001 R09: 00000000008f6420
[   36.769649] R10: 00007f9b846e5000 R11: 0000000000000206 R12: 00007f9b795d6a70
[   36.770807] R13: 00007f9b795e4140 R14: 00007f9b795e3fe0 R15: 0000000100000000
[   36.771955] Code: 83 c7 10 e9 3f 68 d1 ff 0f 1f 44 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 8b 97 b0 00 00 00 48 8d 42 08 48 83 c2 38 <48> 3b 00 74 06 b8 01 00 00 00 c3 48 3b 40 08 75 f4 48 83 c0 10
[   36.775004] RIP: kyber_has_work+0x14/0x40 RSP: ffffc9000209bca0
[   36.776012] CR2: 0000000000000008
[   36.776690] ---[ end trace 4045cbce364ff2a4 ]---
[   36.777527] Kernel panic - not syncing: Fatal exception
[   36.778526] Dumping ftrace buffer:
[   36.779313]    (ftrace buffer empty)
[   36.780081] Kernel Offset: disabled
[   36.780877] ---[ end Kernel panic - not syncing: Fatal exception

Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: stable@vger.kernel.org
Tested-by: Yi Zhang <yi.zhang@redhat.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-01-06 09:25:36 -07:00
Jens Axboe
ca11f209a4 mq-deadline: make it clear that __dd_dispatch_request() works on all hw queues
Don't pass in the hardware queue to __dd_dispatch_request(), since it
leads the reader to believe that we are returning a request for that
specific hardware queue. That's not how mq-deadline works, the state
for determining which request to serve next is shared across all
hardware queues for a device.

Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-01-06 09:23:11 -07:00
Bart Van Assche
14db491726 target: Use sgl_alloc_order() and sgl_free()
Use the sgl_alloc_order() and sgl_free() functions instead of open
coding these functions.

Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Acked-by: Nicholas A. Bellinger <nab@linux-iscsi.org>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-01-06 09:18:00 -07:00
Bart Van Assche
68c6e9cd2f nvmet/rdma: Use sgl_alloc() and sgl_free()
Use the sgl_alloc() and sgl_free() functions instead of open coding
these functions.

Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Cc: Keith Busch <keith.busch@intel.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-01-06 09:18:00 -07:00
Bart Van Assche
4442b56fb5 nvmet/fc: Use sgl_alloc() and sgl_free()
Use the sgl_alloc() and sgl_free() functions instead of open coding
these functions.

Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by:  James Smart <james.smart@broadcom.com>
Cc: Keith Busch <keith.busch@intel.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-01-06 09:18:00 -07:00
Bart Van Assche
8cd579d279 crypto: scompress - use sgl_alloc() and sgl_free()
Use the sgl_alloc() and sgl_free() functions instead of open coding
these functions.

Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-01-06 09:18:00 -07:00
Bart Van Assche
e80a0af475 lib/scatterlist: Introduce sgl_alloc() and sgl_free()
Many kernel drivers contain code that allocates and frees both a
scatterlist and the pages that populate that scatterlist.
Introduce functions in lib/scatterlist.c that perform these tasks
instead of duplicating this functionality in multiple drivers.
Only include these functions in the build if CONFIG_SGL_ALLOC=y
to avoid that the kernel size increases if this functionality is
not used.

Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-01-06 09:18:00 -07:00
Wang Long
bbbc3c1cfa writeback: update comment in inode_io_list_move_locked
The @head can be wb->b_dirty_time, so update the comment.

Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Wang Long <wanglong19@meituan.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-01-06 09:18:00 -07:00
Arnd Bergmann
91f7b74aca DAC960: split up ioctl function to reduce stack size
When CONFIG_KASAN is set, all the local variables in this function are
allocated on the stack together, leading to a warning about possible
kernel stack overflow:

drivers/block/DAC960.c: In function 'DAC960_gam_ioctl':
drivers/block/DAC960.c:7061:1: error: the frame size of 2240 bytes is larger than 2048 bytes [-Werror=frame-larger-than=]

By splitting up the function into smaller chunks, we can avoid that and
make the code slightly more readable at the same time. The coding style
in this file is completely nonstandard, and I chose to not touch that
at all, leaving the unconventional intendation unchanged to make it
easier to review the diff.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-01-06 09:18:00 -07:00
Ming Lei
cf8c0c6a38 block: blk-merge: remove unnecessary check
In this case, 'sectors' can't be zero at all, so remove the check
and let the bio be split.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-01-06 09:18:00 -07:00
Ming Lei
a2d37968d7 block: blk-merge: try to make front segments in full size
When merging one bvec into segment, if the bvec is too big
to merge, current policy is to move the whole bvec into another
new segment.

This patchset changes the policy into trying to maximize size of
front segments, that means in above situation, part of bvec
is merged into current segment, and the remainder is put
into next segment.

This patch prepares for support multipage bvec because
it can be quite common to see this case and we should try
to make front segments in full size.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-01-06 09:18:00 -07:00
Ming Lei
6a501bf080 blk-merge: compute bio->bi_seg_front_size efficiently
It is enough to check and compute bio->bi_seg_front_size just
after the 1st segment is found, but current code checks that
for each bvec, which is inefficient.

This patch follows the way in  __blk_recalc_rq_segments()
for computing bio->bi_seg_front_size, and it is more efficient
and code becomes more readable too.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-01-06 09:18:00 -07:00
Ming Lei
92681eca61 dm-crypt: don't clear bvec->bv_page in crypt_free_buffer_pages()
The bio is always freed after running crypt_free_buffer_pages(), so it
isn't necessary to clear bv->bv_page.

Cc: Mike Snitzer <snitzer@redhat.com>
Cc:dm-devel@redhat.com
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-01-06 09:18:00 -07:00
Ming Lei
c16a8ac3c0 btrfs: avoid accessing bvec table directly for a cloned bio
Commit 17347cec15f919901c90(Btrfs: change how we iterate bios in endio)
mentioned that for dio the submitted bio may be fast cloned, we
can't access the bvec table directly for a cloned bio, so use
bio_get_first_bvec() to retrieve the 1st bvec.

Cc: Chris Mason <clm@fb.com>
Cc: Josef Bacik <jbacik@fb.com>
Cc: David Sterba <dsterba@suse.com>
Cc: linux-btrfs@vger.kernel.org
Cc: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Acked: David Sterba <dsterba@suse.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-01-06 09:18:00 -07:00
Ming Lei
a0b60d725e btrfs: avoid access to .bi_vcnt directly
BTRFS uses bio->bi_vcnt to figure out page numbers, this approach is no
longer valid once we start enabling multipage bvecs.
correct once we start to enable multipage bvec.

Use bio_nr_pages() to do that instead.

Cc: Chris Mason <clm@fb.com>
Cc: Josef Bacik <jbacik@fb.com>
Cc: David Sterba <dsterba@suse.com>
Cc: linux-btrfs@vger.kernel.org
Acked-by: David Sterba <dsterba@suse.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-01-06 09:18:00 -07:00
Ming Lei
25d8be77e1 block: move bio_alloc_pages() to bcache
bcache is the only user of bio_alloc_pages(), so move this function into
bcache, and avoid it being misused in the future.

Also rename it to bch_bio_allo_pages() since it is bcache only.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-01-06 09:18:00 -07:00
Ming Lei
c2421edf5f bcache: comment on direct access to bvec table
All direct access to bvec table are safe even after multipage bvec is
supported.

Cc: linux-bcache@vger.kernel.org
Acked-by: Coly Li <colyli@suse.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-01-06 09:18:00 -07:00
Ming Lei
8f50e35815 dm: limit the max bio size as BIO_MAX_PAGES * PAGE_SIZE
For BIO based DM, some targets aren't ready for dealing with bigger
incoming bio than 1Mbyte, such as crypt target.

Cc: Mike Snitzer <snitzer@redhat.com>
Cc:dm-devel@redhat.com
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-01-06 09:18:00 -07:00