This patch partially reverts 3df0e50 ("xen/blkfront: pseudo support for
multi hardware queues/rings"). The xen-blkfront queue/ring might hang due
to grants allocation failure in the situation when gnttab_free_head is
almost empty while many persistent grants are reserved for this queue/ring.
As persistent grants management was per-queue since 73716df ("xen/blkfront:
make persistent grants pool per-queue"), we should always allocate from
persistent grants first.
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
Signed-off-by: Dongli Zhang <dongli.zhang@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
When ring buf full, hw queue will be stopped. While blkif interrupt consume
request and make free space in ring buf, hw queue will be started again.
But since start queue is protected by spin lock while stop not, that will
cause a race.
interrupt: process:
blkif_interrupt() blkif_queue_rq()
kick_pending_request_queues_locked()
blk_mq_start_stopped_hw_queues()
clear_bit(BLK_MQ_S_STOPPED, &hctx->state)
blk_mq_stop_hw_queue(hctx)
blk_mq_run_hw_queue(hctx, async)
If ring buf is made empty in this case, interrupt will never come, then the
hw queue will be stopped forever, all processes waiting for the pending io
in the queue will hung.
Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Reviewed-by: Ankur Arora <ankur.a.arora@oracle.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
For historical reasons we default to bouncing highmem pages for all block
queues. But the blk-mq drivers are easy to audit to ensure that we don't
need this - scsi and mtip32xx set explicit limits and everyone else doesn't
have any particular ones.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
bios that are re-submitted will pass through blk_queue_split() when
blk_queue_bio() is called, and this will split the bio if necessary.
There is no longer any need to do this splitting in xen-blkfront.
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Replace bi_error with a new bi_status to allow for a clear conversion.
Note that device mapper overloaded bi_error with a private value, which
we'll have to keep arround at least for now and thus propagate to a
proper blk_status_t value.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
Use the same values for use for request completion errors as the return
value from ->queue_rq. BLK_STS_RESOURCE is special cased to cause
a requeue, and all the others are completed as-is.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
Currently we use nornal Linux errno values in the block layer, and while
we accept any error a few have overloaded magic meanings. This patch
instead introduces a new blk_status_t value that holds block layer specific
status codes and explicitly explains their meaning. Helpers to convert from
and to the previous special meanings are provided for now, but I suspect
we want to get rid of them in the long run - those drivers that have a
errno input (e.g. networking) usually get errnos that don't know about
the special block layer overloads, and similarly returning them to userspace
will usually return somethings that strictly speaking isn't correct
for file system operations, but that's left as an exercise for later.
For now the set of errors is a very limited set that closely corresponds
to the previous overloaded errno values, but there is some low hanging
fruite to improve it.
blk_status_t (ab)uses the sparse __bitwise annotations to allow for sparse
typechecking, so that we can easily catch places passing the wrong values.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
Now that all drivers that call blk_mq_complete_requests have a
->complete callback we can remove the direct call to blk_mq_end_request,
as well as the error argument to blk_mq_complete_request.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Bart Van Assche <Bart.VanAssche@sandisk.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
xen-blkfron is the last users using rq->errros for passing back error to
blk-mq, and I'd like to get rid of that. In the longer run the driver
should be moving more of the completion processing into .complete, but
this is the minimal change to move forward for now.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
When a blkfront device is resized from dom0, emit a KOBJ_CHANGE uevent to
notify the guest about the change. This allows for custom udev rules, such
as automatically resizing a filesystem, when an event occurs.
With this patch you get these udev
KERNEL[577.206230] change /devices/vbd-51728/block/xvdb (block)
UDEV [577.226218] change /devices/vbd-51728/block/xvdb (block)
Signed-off-by: Marc Olson <marcolso@amazon.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Constify all instances of blk_mq_ops, as they are never modified.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Instead of keeping two levels of indirection for requests types, fold it
all into the operations. The little caveat here is that previously
cmd_type only applied to struct request, while the request and bio op
fields were set to plain REQ_OP_READ/WRITE even for passthrough
operations.
Instead this patch adds new REQ_OP_* for SCSI passthrough and driver
private requests, althought it has to add two for each so that we
can communicate the data in/out nature of the request.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
Making use of "max_indirect_segments=" has issues:
- blkfront_setup_indirect() may end up with zero psegs when PAGE_SIZE
is sufficiently much larger than XEN_PAGE_SIZE
- the variable driven by the command line option
(xen_blkif_max_segments) has a somewhat different purpose, and hence
should namely never end up being zero
- as long as the specified value is lower than the legacy default,
we better don't use indirect segments at all (or we'd in fact lower
throughput)
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Don't truncate the "feature-persistent" value read from xenstore: Any
non-zero value is supposed to enable the feature, just like is already
being done for feature_secdiscard.
Just like the other feature_* fields, feature_flush and feature_fua are
boolean flags, and hence fit well into a single bit.
Keep all bit fields together to limit gaps.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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Merge tag 'for-linus-4.10-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull xen updates from Juergen Gross:
"Xen features and fixes for 4.10
These are some fixes, a move of some arm related headers to share them
between arm and arm64 and a series introducing a helper to make code
more readable.
The most notable change is David stepping down as maintainer of the
Xen hypervisor interface. This results in me sending you the pull
requests for Xen related code from now on"
* tag 'for-linus-4.10-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: (29 commits)
xen/balloon: Only mark a page as managed when it is released
xenbus: fix deadlock on writes to /proc/xen/xenbus
xen/scsifront: don't request a slot on the ring until request is ready
xen/x86: Increase xen_e820_map to E820_X_MAX possible entries
x86: Make E820_X_MAX unconditionally larger than E820MAX
xen/pci: Bubble up error and fix description.
xen: xenbus: set error code on failure
xen: set error code on failures
arm/xen: Use alloc_percpu rather than __alloc_percpu
arm/arm64: xen: Move shared architecture headers to include/xen/arm
xen/events: use xen_vcpu_id mapping for EVTCHNOP_status
xen/gntdev: Use VM_MIXEDMAP instead of VM_IO to avoid NUMA balancing
xen-scsifront: Add a missing call to kfree
MAINTAINERS: update XEN HYPERVISOR INTERFACE
xenfs: Use proc_create_mount_point() to create /proc/xen
xen-platform: use builtin_pci_driver
xen-netback: fix error handling output
xen: make use of xenbus_read_unsigned() in xenbus
xen: make use of xenbus_read_unsigned() in xen-pciback
xen: make use of xenbus_read_unsigned() in xen-fbfront
...
Use xenbus_read_unsigned() instead of xenbus_scanf() when possible.
This requires to change the type of some reads from int to unsigned,
but these cases have been wrong before: negative values are not allowed
for the modified cases.
Cc: konrad.wilk@oracle.com
Cc: roger.pau@citrix.com
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: David Vrabel <david.vrabel@citrix.com>
Most blk_mq_requeue_request() and blk_mq_add_to_requeue_list() calls
are followed by kicking the requeue list. Hence add an argument to
these two functions that allows to kick the requeue list. This was
proposed by Christoph Hellwig.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
Since blk_mq_requeue_work() starts stopped queues and since
execution of this function can be scheduled after a queue has
been stopped it is not possible to stop queues without using
an additional state variable to track whether or not the queue
has been stopped. Hence modify blk_mq_requeue_work() such that it
does not start stopped queues. My conclusion after a review of
the blk_mq_stop_hw_queues() and blk_mq_{delay_,}kick_requeue_list()
callers is as follows:
* In the dm driver starting and stopping queues should only happen
if __dm_suspend() or __dm_resume() is called and not if the
requeue list is processed.
* In the SCSI core queue stopping and starting should only be
performed by the scsi_internal_device_block() and
scsi_internal_device_unblock() functions but not by any other
function. Although the blk_mq_stop_hw_queue() call in
scsi_queue_rq() may help to reduce CPU load if a LLD queue is
full, figuring out whether or not a queue should be restarted
when requeueing a command would require to introduce additional
locking in scsi_mq_requeue_cmd() to avoid a race with
scsi_internal_device_block(). Avoid this complexity by removing
the blk_mq_stop_hw_queue() call from scsi_queue_rq().
* In the NVMe core only the functions that call
blk_mq_start_stopped_hw_queues() explicitly should start stopped
queues.
* A blk_mq_start_stopped_hwqueues() call must be added in the
xen-blkfront driver in its blkif_recover() function.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Roger Pau Monné <roger.pau@citrix.com>
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: James Bottomley <jejb@linux.vnet.ibm.com>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
All drivers use the default, so provide an inline version of it. If we
ever need other queue mapping we can add an optional method back,
although supporting will also require major changes to the queue setup
code.
This provides better code generation, and better debugability as well.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Current code forgets to free resources in the failure path of
xlvbd_alloc_gendisk(), this patch fix it.
Signed-off-by: Bob Liu <bob.liu@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
blk_mq_update_nr_hw_queues() reset all queue limits to default which it's
not as xen-blkfront expected, introducing blkif_set_queue_limits() to reset
limits with initial correct values.
Signed-off-by: Bob Liu <bob.liu@oracle.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Two places didn't get updated when 64KB page granularity was introduced,
this patch fix them.
Signed-off-by: Bob Liu <bob.liu@oracle.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
- ACPI support for guests on ARM platforms.
- Generic steal time support for arm and x86.
- Support cases where kernel cpu is not Xen VCPU number (e.g., if
in-guest kexec is used).
- Use the system workqueue instead of a custom workqueue in various
places.
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Merge tag 'for-linus-4.8-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull xen updates from David Vrabel:
"Features and fixes for 4.8-rc0:
- ACPI support for guests on ARM platforms.
- Generic steal time support for arm and x86.
- Support cases where kernel cpu is not Xen VCPU number (e.g., if
in-guest kexec is used).
- Use the system workqueue instead of a custom workqueue in various
places"
* tag 'for-linus-4.8-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: (47 commits)
xen: add static initialization of steal_clock op to xen_time_ops
xen/pvhvm: run xen_vcpu_setup() for the boot CPU
xen/evtchn: use xen_vcpu_id mapping
xen/events: fifo: use xen_vcpu_id mapping
xen/events: use xen_vcpu_id mapping in events_base
x86/xen: use xen_vcpu_id mapping when pointing vcpu_info to shared_info
x86/xen: use xen_vcpu_id mapping for HYPERVISOR_vcpu_op
xen: introduce xen_vcpu_id mapping
x86/acpi: store ACPI ids from MADT for future usage
x86/xen: update cpuid.h from Xen-4.7
xen/evtchn: add IOCTL_EVTCHN_RESTRICT
xen-blkback: really don't leak mode property
xen-blkback: constify instance of "struct attribute_group"
xen-blkfront: prefer xenbus_scanf() over xenbus_gather()
xen-blkback: prefer xenbus_scanf() over xenbus_gather()
xen: support runqueue steal time on xen
arm/xen: add support for vm_assist hypercall
xen: update xen headers
xen-pciback: drop superfluous variables
xen-pciback: short-circuit read path used for merging write values
...
Pull block driver updates from Jens Axboe:
"This branch also contains core changes. I've come to the conclusion
that from 4.9 and forward, I'll be doing just a single branch. We
often have dependencies between core and drivers, and it's hard to
always split them up appropriately without pulling core into drivers
when that happens.
That said, this contains:
- separate secure erase type for the core block layer, from
Christoph.
- set of discard fixes, from Christoph.
- bio shrinking fixes from Christoph, as a followup up to the
op/flags change in the core branch.
- map and append request fixes from Christoph.
- NVMeF (NVMe over Fabrics) code from Christoph. This is pretty
exciting!
- nvme-loop fixes from Arnd.
- removal of ->driverfs_dev from Dan, after providing a
device_add_disk() helper.
- bcache fixes from Bhaktipriya and Yijing.
- cdrom subchannel read fix from Vchannaiah.
- set of lightnvm updates from Wenwei, Matias, Johannes, and Javier.
- set of drbd updates and fixes from Fabian, Lars, and Philipp.
- mg_disk error path fix from Bart.
- user notification for failed device add for loop, from Minfei.
- NVMe in general:
+ NVMe delay quirk from Guilherme.
+ SR-IOV support and command retry limits from Keith.
+ fix for memory-less NUMA node from Masayoshi.
+ use UINT_MAX for discard sectors, from Minfei.
+ cancel IO fixes from Ming.
+ don't allocate unused major, from Neil.
+ error code fixup from Dan.
+ use constants for PSDT/FUSE from James.
+ variable init fix from Jay.
+ fabrics fixes from Ming, Sagi, and Wei.
+ various fixes"
* 'for-4.8/drivers' of git://git.kernel.dk/linux-block: (115 commits)
nvme/pci: Provide SR-IOV support
nvme: initialize variable before logical OR'ing it
block: unexport various bio mapping helpers
scsi/osd: open code blk_make_request
target: stop using blk_make_request
block: simplify and export blk_rq_append_bio
block: ensure bios return from blk_get_request are properly initialized
virtio_blk: use blk_rq_map_kern
memstick: don't allow REQ_TYPE_BLOCK_PC requests
block: shrink bio size again
block: simplify and cleanup bvec pool handling
block: get rid of bio_rw and READA
block: don't ignore -EOPNOTSUPP blkdev_issue_write_same
block: introduce BLKDEV_DISCARD_ZERO to fix zeroout
NVMe: don't allocate unused nvme_major
nvme: avoid crashes when node 0 is memoryless node.
nvme: Limit command retries
loop: Make user notify for adding loop device failed
nvme-loop: fix nvme-loop Kconfig dependencies
nvmet: fix return value check in nvmet_subsys_alloc()
...
Pull core block updates from Jens Axboe:
- the big change is the cleanup from Mike Christie, cleaning up our
uses of command types and modified flags. This is what will throw
some merge conflicts
- regression fix for the above for btrfs, from Vincent
- following up to the above, better packing of struct request from
Christoph
- a 2038 fix for blktrace from Arnd
- a few trivial/spelling fixes from Bart Van Assche
- a front merge check fix from Damien, which could cause issues on
SMR drives
- Atari partition fix from Gabriel
- convert cfq to highres timers, since jiffies isn't granular enough
for some devices these days. From Jan and Jeff
- CFQ priority boost fix idle classes, from me
- cleanup series from Ming, improving our bio/bvec iteration
- a direct issue fix for blk-mq from Omar
- fix for plug merging not involving the IO scheduler, like we do for
other types of merges. From Tahsin
- expose DAX type internally and through sysfs. From Toshi and Yigal
* 'for-4.8/core' of git://git.kernel.dk/linux-block: (76 commits)
block: Fix front merge check
block: do not merge requests without consulting with io scheduler
block: Fix spelling in a source code comment
block: expose QUEUE_FLAG_DAX in sysfs
block: add QUEUE_FLAG_DAX for devices to advertise their DAX support
Btrfs: fix comparison in __btrfs_map_block()
block: atari: Return early for unsupported sector size
Doc: block: Fix a typo in queue-sysfs.txt
cfq-iosched: Charge at least 1 jiffie instead of 1 ns
cfq-iosched: Fix regression in bonnie++ rewrite performance
cfq-iosched: Convert slice_resid from u64 to s64
block: Convert fifo_time from ulong to u64
blktrace: avoid using timespec
block/blk-cgroup.c: Declare local symbols static
block/bio-integrity.c: Add #include "blk.h"
block/partition-generic.c: Remove a set-but-not-used variable
block: bio: kill BIO_MAX_SIZE
cfq-iosched: temporarily boost queue priority for idle classes
block: drbd: avoid to use BIO_MAX_SIZE
block: bio: remove BIO_MAX_SECTORS
...
... for single items being collected: It is more typesafe (as the
compiler can check format string and to-be-written-to variable match)
and requires one less parameter to be passed.
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Uncompleted reqs used to be 'saved and resubmitted' in blkfront_recover() during
migration, but that's too late after multi-queue was introduced.
After a migrate to another host (which may not have multiqueue support), the
number of rings (block hardware queues) may be changed and the ring and shadow
structure will also be reallocated.
The blkfront_recover() then can't 'save and resubmit' the real
uncompleted reqs because shadow structure have been reallocated.
This patch fixes this issue by moving the 'save' logic out of
blkfront_recover() to earlier place in blkfront_resume().
The 'resubmit' is not changed and still in blkfront_recover().
Signed-off-by: Bob Liu <bob.liu@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: stable@vger.kernel.org
For block drivers that specify a parent device, convert them to use
device_add_disk().
This conversion was done with the following semantic patch:
@@
struct gendisk *disk;
expression E;
@@
- disk->driverfs_dev = E;
...
- add_disk(disk);
+ device_add_disk(E, disk);
@@
struct gendisk *disk;
expression E1, E2;
@@
- disk->driverfs_dev = E1;
...
E2 = disk;
...
- add_disk(E2);
+ device_add_disk(E1, E2);
...plus some manual fixups for a few missed conversions.
Cc: Jens Axboe <axboe@fb.com>
Cc: Keith Busch <keith.busch@intel.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: James Bottomley <James.Bottomley@hansenpartnership.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Instead of overloading the discard support with the REQ_SECURE flag.
Use the opportunity to rename the queue flag as well, and remove the
dead checks for this flag in the RAID 1 and RAID 10 drivers that don't
claim support for secure erase.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
After a migrate to another host (which may not have multiqueue
support), the number of rings (block hardware queues)
may be changed and the ring info structure will also be reallocated.
This patch fixes two related bugs:
* call blk_mq_update_nr_hw_queues() to make blk-core know the number
of hardware queues have been changed.
* Don't store rinfo pointer to hctx->driver_data, because rinfo may be
reallocated so use hctx->queue_num to get the rinfo structure instead.
Signed-off-by: Bob Liu <bob.liu@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Sometimes blkfront may twice receive blkback_changed() notification
(XenbusStateConnected) after migration, which will cause
talk_to_blkback() to be called twice too and confuse xen-blkback.
The flow is as follow:
blkfront blkback
blkfront_resume()
> talk_to_blkback()
> Set blkfront to XenbusStateInitialised
front changed()
> Connect()
> Set blkback to XenbusStateConnected
blkback_changed()
> Skip talk_to_blkback()
because frontstate == XenbusStateInitialised
> blkfront_connect()
> Set blkfront to XenbusStateConnected
-----
And here we get another XenbusStateConnected notification leading
to:
-----
blkback_changed()
> because now frontstate != XenbusStateInitialised
talk_to_blkback() is also called again
> blkfront state changed from
XenbusStateConnected to XenbusStateInitialised
(Which is not correct!)
front_changed():
> Do nothing because blkback
already in XenbusStateConnected
Now blkback is in XenbusStateConnected but blkfront is still
in XenbusStateInitialised - leading to no disks.
Poking of the XenbusStateConnected state is allowed (to deal with
block disk change) and has to be dealt with. The most likely
cause of this bug are custom udev scripts hooking up the disks
and then validating the size.
Signed-off-by: Bob Liu <bob.liu@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
The last patch added a REQ_OP_FLUSH for request_fn drivers
and the next patch renames REQ_FLUSH to REQ_PREFLUSH which
will be used by file systems and make_request_fn drivers so
they can send a write/flush combo.
This patch drops xen's use of REQ_FLUSH to track if it supports
REQ_OP_FLUSH requests, so REQ_FLUSH can be deleted.
Signed-off-by: Mike Christie <mchristi@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Juergen Gross <kernel@pfupf.net>
Signed-off-by: Jens Axboe <axboe@fb.com>
This adds a REQ_OP_FLUSH operation that is sent to request_fn
based drivers by the block layer's flush code, instead of
sending requests with the request->cmd_flags REQ_FLUSH bit set.
Signed-off-by: Mike Christie <mchristi@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
The req operation REQ_OP is separated from the rq_flag_bits
definition. This converts the block layer drivers to
use req_op to get the op from the request struct.
Signed-off-by: Mike Christie <mchristi@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
This has callers of submit_bio/submit_bio_wait set the bio->bi_rw
instead of passing it in. This makes that use the same as
generic_make_request and how we set the other bio fields.
Signed-off-by: Mike Christie <mchristi@redhat.com>
Fixed up fs/ext4/crypto.c
Signed-off-by: Jens Axboe <axboe@fb.com>
Pull block driver updates from Jens Axboe:
"This is the block driver pull request for this merge window. It sits
on top of for-4.6/core, that was just sent out.
This contains:
- A set of fixes for lightnvm. One from Alan, fixing an overflow,
and the rest from the usual suspects, Javier and Matias.
- A set of fixes for nbd from Markus and Dan, and a fixup from Arnd
for correct usage of the signed 64-bit divider.
- A set of bug fixes for the Micron mtip32xx, from Asai.
- A fix for the brd discard handling from Bart.
- Update the maintainers entry for cciss, since that hardware has
transferred ownership.
- Three bug fixes for bcache from Eric Wheeler.
- Set of fixes for xen-blk{back,front} from Jan and Konrad.
- Removal of the cpqarray driver. It has been disabled in Kconfig
since 2013, and we were initially scheduled to remove it in 3.15.
- Various updates and fixes for NVMe, with the most important being:
- Removal of the per-device NVMe thread, replacing that with a
watchdog timer instead. From Christoph.
- Exposing the namespace WWID through sysfs, from Keith.
- Set of cleanups from Ming Lin.
- Logging the controller device name instead of the underlying
PCI device name, from Sagi.
- And a bunch of fixes and optimizations from the usual suspects
in this area"
* 'for-4.6/drivers' of git://git.kernel.dk/linux-block: (49 commits)
NVMe: Expose ns wwid through single sysfs entry
drivers:block: cpqarray clean up
brd: Fix discard request processing
cpqarray: remove it from the kernel
cciss: update MAINTAINERS
NVMe: Remove unused sq_head read in completion path
bcache: fix cache_set_flush() NULL pointer dereference on OOM
bcache: cleaned up error handling around register_cache()
bcache: fix race of writeback thread starting before complete initialization
NVMe: Create discard zero quirk white list
nbd: use correct div_s64 helper
mtip32xx: remove unneeded variable in mtip_cmd_timeout()
lightnvm: generalize rrpc ppa calculations
lightnvm: remove struct nvm_dev->total_blocks
lightnvm: rename ->nr_pages to ->nr_sects
lightnvm: update closed list outside of intr context
xen/blback: Fit the important information of the thread in 17 characters
lightnvm: fold get bb tbl when using dual/quad plane mode
lightnvm: fix up nonsensical configure overrun checking
xen-blkback: advertise indirect segment support earlier
...
"max" is rather ambiguous and carries pretty little meaning, the more
that there are also "max_queues" and "max_ring_page_order". Make this
"max_indirect_segments" instead, and at once change the type from int
to uint (to match the respective variable's type).
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Need to reallocate ring info in the resume path, because info->rinfo was freed
in blkif_free(). And 'multi-queue-max-queues' backend reports may have been
changed.
Signed-off-by: Bob Liu <bob.liu@oracle.com>
Reported-and-Tested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
We have split the setting up of all the resources in two steps:
1) talk_to_blkback - which figures out the num_ring_pages (from
the default value of zero), sets up shadow and so
2) blkfront_connect - does the real part of filling out the
internal structures.
The problem is if we bypass the 1) step and go straight to 2)
and call blkfront_setup_indirect where we use the macro
BLK_RING_SIZE - which returns an negative value (because
sz is zero - since num_ring_pages is zero - since it has never
been set).
We can fix this by making sure that we always have called
talk_to_blkback before going to blkfront_connect.
Or we could set in blkfront_probe info->nr_ring_pages = 1
to have a default value. But that looks odd - as we haven't
actually negotiated any ring size.
This patch changes XenbusStateConnected state to detect if
we haven't done the initial handshake - and if so continue
on as if were in XenbusStateInitWait state.
We also roll the error recovery (freeing the structure) into
talk_to_blkback error path - which is safe since that function
is only called from blkback_changed.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
The minimal size of request in the block framework is always PAGE_SIZE.
It means that when 64KB guest is support, the request will at least be
64KB.
Although, if the backend doesn't support indirect descriptor (such as QDISK
in QEMU), a ring request is only able to accommodate 11 segments of 4KB
(i.e 44KB).
The current frontend is assuming that an I/O request will always fit in
a ring request. This is not true any more when using 64KB page
granularity and will therefore crash during boot.
On ARM64, the ABI is completely neutral to the page granularity used by
the domU. The guest has the choice between different page granularity
supported by the processors (for instance on ARM64: 4KB, 16KB, 64KB).
This can't be enforced by the hypervisor and therefore it's possible to
run guests using different page granularity.
So we can't mandate the block backend to support indirect descriptor
when the frontend is using 64KB page granularity and have to fix it
properly in the frontend.
The solution exposed below is based on modifying directly the frontend
guest rather than asking the block framework to support smaller size
(i.e < PAGE_SIZE). This is because the change is the block framework are
not trivial as everything seems to relying on a struct *page (see [1]).
Although, it may be possible that someone succeed to do it in the future
and we would therefore be able to use it.
Given that a block request may not fit in a single ring request, a
second request is introduced for the data that cannot fit in the first
one. This means that the second ring request should never be used on
Linux if the page size is smaller than 44KB.
To achieve the support of the extra ring request, the block queue size
is divided by two. Therefore, the ring will always contain enough space
to accommodate 2 ring requests. While this will reduce the overall
performance, it will make the implementation more contained. The way
forward to get better performance is to implement in the backend either
indirect descriptor or multiple grants ring.
Note that the parameters blk_queue_max_* helpers haven't been updated.
The block code will set the mimimum size supported and we may be able
to support directly any change in the block framework that lower down
the minimal size of a request.
[1] http://lists.xen.org/archives/html/xen-devel/2015-08/msg02200.html
Signed-off-by: Julien Grall <julien.grall@citrix.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
The code to get a request is always the same. Therefore we can factorize
it in a single function.
Signed-off-by: Julien Grall <julien.grall@citrix.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
According to this piece code:
"
pr_info("Invalid max_ring_order (%d), will use default max: %d.\n",
xen_blkif_max_ring_order, XENBUS_MAX_RING_GRANT_ORDER);
"
if xen_blkif_max_ring_order is bigger that XENBUS_MAX_RING_GRANT_ORDER,
need to set xen_blkif_max_ring_order using XENBUS_MAX_RING_GRANT_ORDER,
but not 0.
Signed-off-by: Peng Fan <van.freenix@gmail.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: "Roger Pau Monné" <roger.pau@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Make persistent grants per-queue/ring instead of per-device, so that we can
drop the 'dev_lock' and get better scalability.
Test was done based on null_blk driver:
dom0: v4.2-rc8 16vcpus 10GB "modprobe null_blk"
domu: v4.2-rc8 16vcpus 10GB
[test]
rw=read
direct=1
ioengine=libaio
bs=4k
time_based
runtime=30
filename=/dev/xvdb
numjobs=16
iodepth=64
iodepth_batch=64
iodepth_batch_complete=64
group_reporting
Queues: 1 4 8 16
Iops orig(k): 810 1064 780 700
Iops patched(k): 810 1230(~20%) 1024(~20%) 850(~20%)
Signed-off-by: Bob Liu <bob.liu@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
We do the same exact operations a bit earlier in the
function.
Signed-off-by: Bob Liu <bob.liu@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
The max number of hardware queues for xen/blkfront is set by parameter
'max_queues'(default 4), while it is also capped by the max value that the
xen/blkback exposes through XenStore key 'multi-queue-max-queues'.
The negotiated number is the smaller one and would be written back to xenstore
as "multi-queue-num-queues", blkback needs to read this negotiated number.
Signed-off-by: Bob Liu <bob.liu@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
