We have an nvme device that has a concept of a stripe size. IO requests
that do not transfer data crossing a stripe boundary has greater
performance compared to IO that does cross it. This patch sets the
stripe size for the device if the device and vendor ids match one with
this feature and splits IO requests that cross the stripe boundary.
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
It is possible a bio request can not be submitted as a single NVMe IO
command if the bio_vec is not mergeable with the NVMe PRP alignement
constraints. This condition was handled by submitting an IO for the
mergeable portion then submitting a follow on IO for the remaining data
after the previous IO completes. The remainder to be sent was tracked
by manipulating the bio->bi_idx and bio->bi_sector. This patch splits
the request as many times as necessary and submits the bios together.
Since submitting the bio may cause it to be requeued on split,
nvme_resubmit_bios had to be modified to remove the wait queue when
the bio list is empty prior to submitting the bio since a split would
have added the wait queue a second time, corrupting the wait queue head
task list.
There are a few other benefits from doing this: it fixes a potential
issue with the previous handling of a non-mergeable bio as the requeuing
method could would use an unlocked nvme_queue if the callback isn't
invoked on the queue's associated cpu; it will be possible to retry a
failed bio if desired at some later time since it does not manipulate
the original bio; the bio integrity extensions require the bio to be in
its original condition for the checks to work correctly if we implement
the end-to-end data protection in the future.
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
There is no situation that could occur where we could error out of this
function and require cleaning up allocated namespaces.
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
The nvme_queue's depth is not set if we fail to allocate submission queue
entries, which was being used to determine how much coherent memory to
free on error. Use the depth variable instead.
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Fixes a potential memory leak if requesting the admin queue irq fails.
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
The kthread has two tasks; handling timeouts (for which it runs once per
second), and submitting queued BIOs. If a BIO happens to be queued after
the thread has processed the queue but before it calls schedule_timeout(),
the thread will sleep for a second before submitting it, which can cause
performance problems in some rare cases (that will become more common in
a subsequent patch).
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Tested-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Registers a miscellaneous device for each nvme controller probed. This
creates character device files as /dev/nvmeN, where N is the device
instance, and supports nvme admin ioctl commands so devices without
namespaces can be managed.
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
When constructing the command, dsmgmt needs to be treated as a 32-bit
value, not a 16-bit value. reftag, apptag and appmask all need to be
converted from native-endian to little-endian. Again, sparse's bitwise
warnings caught this problem. Thanks to Keith for pointing out the
correct way to fix the reftag.
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Acked-by: Keith Busch <keith.busch@intel.com>
The sparse bitwise checks pointed out that I needed to shift the status
before changing its endianness, not after.
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
The nvme_dev_add() function currently returns the last error code that it
saw, which (if everything else succeeds) happens to be the result of an
optional command, so it can legitimately fail. Looking at the error path
more closely reveals that we should return success from this function,
even if no device namespaces are added. So once the queues are created
and the device has responded to Identify, make sure that this function
succeeds.
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Acked-by: Keith Busch <keith.busch@intel.com>
Introduce nvme_block_nr() to help convert sectors to block numbers.
This fixes an integer overflow in the SCSI conversion layer, and it's
slightly less typing than opencoding it.
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Acked-by: Keith Busch <keith.busch@intel.com>
The nvme driver has a "once per second" event where the management kthread
wakes up the system and then reschedules itself for 1 second later.
For power efficiency reasons, I'd like this timer to happen together
with other wakeups in the system.
This patch makes the schedule_timeout() call in the kthread use
round_jiffies_relative(), causing the wakeup to at least align with other
"once per X seconds" events in the kernel.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Tested-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Translates SCSI commands in SG_IO ioctl to NVMe commands.
Uses the scsi-nvme translation spec from nvmexpress.org as reference.
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
The SCSI emulation has the ability to send format commands, so we need
to add the definition of the command. Also add a missing error code.
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
nvme-scsi.c uses several data structures and definitions that were
previously private to nvme-core.c. Move the definitions to nvme.h,
protected by __KERNEL__.
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
In preparation for adding nvme-scsi.c
It is preferable to retain the module name 'nvme'
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Keith Busch