We only call __blk_mq_put_tag() and __blk_mq_put_reserved_tag()
from blk_mq_put_tag(), so just inline the two calls instead of
having them as separate functions.
Signed-off-by: Jens Axboe <axboe@fb.com>
We currently use num_possible_cpus(), but that breaks on sparc64 where
the CPU ID space is discontig. Use nr_cpu_ids as the highest CPU ID
instead, so we don't end up reading from invalid memory.
Cc: stable@kernel.org # 3.13+
Signed-off-by: Jens Axboe <axboe@fb.com>
SPC-3 defines SERVICE ACTION IN(12) and SERVICE ACTION IN(16).
So rename SERVICE_ACTION_IN to SERVICE_ACTION_IN_16 to be
consistent with SPC and to allow for better distinction.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Tested-by: Robert Elliott <elliott@hp.com>
Reviewed-by: Robert Elliott <elliott@hp.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Many block drivers accounting io stat based on bio (e.g. NVMe...),
the blk_account_io_start/end() which is based on request
does not make sense to them, so here we introduce the similar help
function named generic_start/end_io_acct base on raw sectors, and it can
simplify some driver's open io accounting code.
Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Don't duplicate the code to handle the not cpu bounce case in the
caller, do it inside blk_mq_hctx_next_cpu instead.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
We can get here from blkdev_ioctl() -> blkpg_ioctl() -> add_partition()
with a user passed in partno value. If we pass in 0x7fffffff, the
new target in disk_expand_part_tbl() overflows the 'int' and we
access beyond the end of ptbl->part[] and even write to it when we
do the rcu_assign_pointer() to assign the new partition.
Reported-by: David Ramos <daramos@stanford.edu>
Cc: stable@kernel.org
Signed-off-by: Jens Axboe <axboe@fb.com>
It's silly to use blk_mq_free_request() which in turn maps the
request to the hardware queue, for places where we already know
what the hardware queue is. This saves us an extra mapping of a
hardware queue on request completion, if the caller knows this
information already.
Signed-off-by: Jens Axboe <axboe@fb.com>
Currently scsi piggy backs on the block layer to define the concept
of a tagged command. But we want to be able to have block-level host-wide
tags assigned even for untagged commands like the initial INQUIRY, so add
a new SCSI-level flag for commands that are tagged at the scsi level, so
that even commands without that set can have tags assigned to them. Note
that this alredy is the case for the blk-mq code path, and this just lets
the old path catch up with it.
We also set this flag based upon sdev->simple_tags instead of the block
queue flag, so that it is entirely independent of the block layer tagging,
and thus always correct even if a driver doesn't use block level tagging
yet.
Also remove the old blk_rq_tagged; it was only used by SCSI drivers, and
removing it forces them to look for the proper replacement.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
The queuecommand() callback functions in SCSI low-level drivers
need to know which hardware context has been selected by the
block layer. Since this information is not available in the
request structure, and since passing the hctx pointer directly to
the queuecommand callback function would require modification of
all SCSI LLDs, add a function to the block layer that allows to
query the hardware context index.
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Acked-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
For cloned bio, bio->bi_vcnt can't be used at all, and we
have resort to bio_segments() to figure out how many
segment there are in the bio.
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
blk-mq is using preempt_disable/enable in order to ensure that the
queue runners are placed on the right CPU. This does not work with
the RT patches, because __blk_mq_run_hw_queue takes a non-raw
spinlock with the preemption-disabled region. If there is contention
on the lock, this violates the rules for preemption-disabled regions.
While this should be easily fixable within the RT patches just by doing
migrate_disable/enable, we can do better and document _why_ this
particular region runs with disabled preemption. After the previous
patch, it is trivial to switch it to get/put_cpu; the RT patches then
can change it to get_cpu_light, which lets virtio-blk run under RT
kernels.
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Reported-by: Clark Williams <williams@redhat.com>
Tested-by: Clark Williams <williams@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
preempt_disable/enable surrounds every call to blk_mq_run_hw_queue,
except the one in blk-flush.c. In fact that one is always asynchronous,
and it does not need smp_processor_id().
We can do the same for all other calls, avoiding preempt_disable when
async is true. This avoids peppering blk-mq.c with preemption-disabled
regions.
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Reported-by: Clark Williams <williams@redhat.com>
Tested-by: Clark Williams <williams@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Fix an error path in SCSI_IOCTL_SEND_COMMAND that calls
blk_put_request(rq) on an invalid IS_ERR(rq) pointer.
Fixes: a492f07545 ("block,scsi: fixup blk_get_request dead queue scenarios")
Signed-off-by: Tony Battersby <tonyb@cybernetics.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
q->mq_usage_counter is a percpu_ref which is killed and drained when
the queue is frozen. On a CPU hotplug event, blk_mq_queue_reinit()
which involves freezing the queue is invoked on all existing queues.
Because percpu_ref killing and draining involve a RCU grace period,
doing the above on one queue after another may take a long time if
there are many queues on the system.
This patch splits out initiation of freezing and waiting for its
completion, and updates blk_mq_queue_reinit_notify() so that the
queues are frozen in parallel instead of one after another. Note that
freezing and unfreezing are moved from blk_mq_queue_reinit() to
blk_mq_queue_reinit_notify().
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Christian Borntraeger <borntraeger@de.ibm.com>
Tested-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Priority of a merged request is computed by ioprio_best(). If one of the
requests has undefined priority (IOPRIO_CLASS_NONE) and another request
has priority from IOPRIO_CLASS_BE, the function will return the
undefined priority which is wrong. Fix the function to properly return
priority of a request with the defined priority.
Fixes: d58cdfb89c
CC: stable@vger.kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Drivers can now tell blk-mq if they take advantage of the deferred
issue through 'last' or not. If they do, don't do queue-direct
for sync IO. This is a preparation patch for the nvme conversion.
Signed-off-by: Jens Axboe <axboe@fb.com>
Since we have the notion of a 'last' request in a chain, we can use
this to have the hardware optimize the issuing of requests. Add
a list_head parameter to queue_rq that the driver can use to
temporarily store hw commands for issue when 'last' is true. If we
are doing a chain of requests, pass in a NULL list for the first
request to force issue of that immediately, then batch the remainder
for deferred issue until the last request has been sent.
Instead of adding yet another argument to the hot ->queue_rq path,
encapsulate the passed arguments in a blk_mq_queue_data structure.
This is passed as a constant, and has been tested as faster than
passing 4 (or even 3) args through ->queue_rq. Update drivers for
the new ->queue_rq() prototype. There are no functional changes
in this patch for drivers - if they don't use the passed in list,
then they will just queue requests individually like before.
Signed-off-by: Jens Axboe <axboe@fb.com>
while compiling integer err was showing as a set but unused variable.
elevator_init_fn can be either cfq_init_queue or deadline_init_queue
or noop_init_queue.
all three of these functions are returning -ENOMEM if they fail to
allocate the queue.
so we should actually be returning the error code rather than
returning 0 always.
Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org>
Signed-off-by: Jens Axboe <axboe@fb.com>
When sg_scsi_ioctl() fails to prepare request to submit in
blk_rq_map_kern() we jump to a label where we just end up copying
(luckily zeroed-out) kernel buffer to userspace instead of reporting
error. Fix the problem by jumping to the right label.
CC: Jens Axboe <axboe@kernel.dk>
CC: linux-scsi@vger.kernel.org
CC: stable@vger.kernel.org
Coverity-id: 1226871
Signed-off-by: Jan Kara <jack@suse.cz>
Fixed up the, now unused, out label.
Signed-off-by: Jens Axboe <axboe@fb.com>
The problem is introduced by commit 764f612c6c3c231b(blk-merge:
don't compute bi_phys_segments from bi_vcnt for cloned bio),
and merge is needed if number of current segment isn't less than
max segments.
Strictly speaking, bio->bi_vcnt shouldn't be used here since
it may not be accurate in cases of both cloned bio or bio cloned
from, but bio_segments() is a bit expensive, and bi_vcnt is still
the biggest number, so the approach should work.
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Set max_sectors to the value the drivers provides as hardware limit by
default. Linux had proper I/O throttling for a long time and doesn't
rely on a artifically small maximum I/O size anymore. By not limiting
the I/O size by default we remove an annoying tuning step required for
most Linux installation.
Note that both the user, and if absolutely required the driver can still
impose a limit for FS requests below max_hw_sectors_kb.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
Pull core block layer changes from Jens Axboe:
"This is the core block IO pull request for 3.18. Apart from the new
and improved flush machinery for blk-mq, this is all mostly bug fixes
and cleanups.
- blk-mq timeout updates and fixes from Christoph.
- Removal of REQ_END, also from Christoph. We pass it through the
->queue_rq() hook for blk-mq instead, freeing up one of the request
bits. The space was overly tight on 32-bit, so Martin also killed
REQ_KERNEL since it's no longer used.
- blk integrity updates and fixes from Martin and Gu Zheng.
- Update to the flush machinery for blk-mq from Ming Lei. Now we
have a per hardware context flush request, which both cleans up the
code should scale better for flush intensive workloads on blk-mq.
- Improve the error printing, from Rob Elliott.
- Backing device improvements and cleanups from Tejun.
- Fixup of a misplaced rq_complete() tracepoint from Hannes.
- Make blk_get_request() return error pointers, fixing up issues
where we NULL deref when a device goes bad or missing. From Joe
Lawrence.
- Prep work for drastically reducing the memory consumption of dm
devices from Junichi Nomura. This allows creating clone bio sets
without preallocating a lot of memory.
- Fix a blk-mq hang on certain combinations of queue depths and
hardware queues from me.
- Limit memory consumption for blk-mq devices for crash dump
scenarios and drivers that use crazy high depths (certain SCSI
shared tag setups). We now just use a single queue and limited
depth for that"
* 'for-3.18/core' of git://git.kernel.dk/linux-block: (58 commits)
block: Remove REQ_KERNEL
blk-mq: allocate cpumask on the home node
bio-integrity: remove the needless fail handle of bip_slab creating
block: include func name in __get_request prints
block: make blk_update_request print prefix match ratelimited prefix
blk-merge: don't compute bi_phys_segments from bi_vcnt for cloned bio
block: fix alignment_offset math that assumes io_min is a power-of-2
blk-mq: Make bt_clear_tag() easier to read
blk-mq: fix potential hang if rolling wakeup depth is too high
block: add bioset_create_nobvec()
block: use bio_clone_fast() in blk_rq_prep_clone()
block: misplaced rq_complete tracepoint
sd: Honor block layer integrity handling flags
block: Replace strnicmp with strncasecmp
block: Add T10 Protection Information functions
block: Don't merge requests if integrity flags differ
block: Integrity checksum flag
block: Relocate bio integrity flags
block: Add a disk flag to block integrity profile
block: Add prefix to block integrity profile flags
...
All other allocs are done on the specific node, somehow the
cpumask for hw queue runs was missed. Fix that by using
zalloc_cpumask_var_node() in blk_mq_init_queue().
Signed-off-by: Jens Axboe <axboe@fb.com>
Jens Axboe
Hannes Reinecke
Gu Zheng
Christoph Hellwig
Bart Van Assche
Ming Lei
Paolo Bonzini
Tony Battersby
Tejun Heo
Jan Kara
Sudip Mukherjee
Linus Torvalds