Commit Graph

131 Commits

Author SHA1 Message Date
Mark Kanda
0a75b60cdb virtio-blk: reject configs with logical block size > physical block size
virtio-blk logical block size should never be larger than physical block
size because it doesn't make sense to have such configurations. QEMU doesn't
have a way to effectively express this condition; the best it can do is
report the physical block exponent as 0 - indicating the logical block size
equals the physical block size.

This is identical to commit 3da023b582
but applied to virtio-blk (instead of virtio-scsi).

Signed-off-by: Mark Kanda <mark.kanda@oracle.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Ameya More <ameya.more@oracle.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 773169891f9f2deb4cb7c4ef2655580dbe24c1d1.1513005190.git.mark.kanda@oracle.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-12-19 10:25:09 +00:00
Mark Kanda
6040aedddb virtio-blk: make queue size configurable
Depending on the configuration, it can be beneficial to adjust the virtio-blk
queue size to something other than the current default of 128. Add a new
property to make the queue size configurable.

Signed-off-by: Mark Kanda <mark.kanda@oracle.com>
Reviewed-by: Karl Heubaum <karl.heubaum@oracle.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Ameya More <ameya.more@oracle.com>
Message-id: 52e6d742811f10dbd16e996e86cf375b9577c187.1513005190.git.mark.kanda@oracle.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-12-19 10:25:09 +00:00
Mao Zhongyi
ceff3e1f01 hw/block: Use errp directly rather than local_err
[Drop virtio_blk_data_plane_create() change that misinterprets return
value when the virtio transport does not support dataplane.
--Stefan]

Cc: John Snow <jsnow@redhat.com>
Cc: Kevin Wolf <kwolf@redhat.com>
Cc: Max Reitz <mreitz@redhat.com>
Cc: Keith Busch <keith.busch@intel.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Markus Armbruster <armbru@redhat.com>

Signed-off-by: Mao Zhongyi <maozy.fnst@cn.fujitsu.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: e77848d3735ba590f23ffbf8094379c646c33d79.1511317952.git.maozy.fnst@cn.fujitsu.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-12-19 10:25:03 +00:00
Paolo Bonzini
08e2c9f19c scsi: move block/scsi.h to include/scsi/constants.h
Complete the transition by renaming this header, which was
shared by block/iscsi.c and the SCSI emulation code.

Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-09-19 14:09:31 +02:00
Stefan Hajnoczi
17d0bc01bf virtio-blk: handle blk_getlength() errors
If blk_getlength() fails in virtio_blk_update_config() consider the disk
image length to be 0 bytes.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 20170808122251.29815-1-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-08-10 14:33:43 +01:00
Fam Zheng
d679ac09f0 virtio-blk: Convert to DEFINE_PROP_LINK
Signed-off-by: Fam Zheng <famz@redhat.com>
Message-Id: <20170714021509.23681-7-famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-07-14 12:04:42 +02:00
Stefan Hajnoczi
a576ceac39 virtio-blk: trace vdev so devices can be distinguished
It is hard to analyze trace logs with multiple virtio-blk devices
because none of the trace events include the VirtIODevice *vdev.

This patch adds vdev so it's clear which device a request is associated
with.

I considered using VirtIOBlock *s instead but VirtIODevice *vdev is more
general and may be correlated with generic virtio trace events like
virtio_set_status.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 20170614092930.11234-1-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-06-29 14:31:16 +01:00
Fam Zheng
1d29b5b049 virtio-blk: Remove useless condition around g_free()
Laszlo spotted and studied this wasteful "if". He pointed out:

The original virtio_blk_free_request needed an "if" as it accesses one
field, since 671ec3f056 ("virtio-blk: Convert VirtIOBlockReq.elem to
pointer", 2014-06-11); later on in f897bf751f ("virtio-blk: embed
VirtQueueElement in VirtIOBlockReq", 2014-07-09) the field became
embedded, so the "if" became unnecessary (at which point we were using
g_slice_free(), but it is the same.

Now drop it.

Reported-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2017-05-10 10:19:23 +03:00
Kevin Wolf
a17c17a274 hw/block: Request permissions
This makes all device emulations with a qdev drive property request
permissions on their BlockBackend. The only thing we block at this point
is resizing images for some devices that can't support it.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Acked-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2017-02-28 20:40:36 +01:00
Paolo Bonzini
b9e413dd37 block: explicitly acquire aiocontext in aio callbacks that need it
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170213135235.12274-16-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-21 11:39:39 +00:00
Paolo Bonzini
1919631e6b block: explicitly acquire aiocontext in bottom halves that need it
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170213135235.12274-15-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-21 11:39:39 +00:00
Paolo Bonzini
9d45665448 block: explicitly acquire aiocontext in callbacks that need it
This covers both file descriptor callbacks and polling callbacks,
since they execute related code.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170213135235.12274-14-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-21 11:39:36 +00:00
Fam Zheng
0793169870 virtio: Report real progress in VQ aio poll handler
In virtio_queue_host_notifier_aio_poll, not all "!virtio_queue_empty()"
cases are making true progress.

Currently the offending one is virtio-scsi event queue, whose handler
does nothing if no event is pending. As a result aio_poll() will spin on
the "non-empty" VQ and take 100% host CPU.

Fix this by reporting actual progress from virtio queue aio handlers.

Reported-by: Ed Swierk <eswierk@skyportsystems.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Tested-by: Ed Swierk <eswierk@skyportsystems.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-02-17 21:52:30 +02:00
Jason Wang
8607f5c307 virtio: convert to use DMA api
Currently, all virtio devices bypass IOMMU completely. This is because
address_space_memory is assumed and used during DMA emulation. This
patch converts the virtio core API to use DMA API. This idea is

- introducing a new transport specific helper to query the dma address
  space. (only pci version is implemented).
- query and use this address space during virtio device guest memory
  accessing when iommu platform (VIRTIO_F_IOMMU_PLATFORM) was enabled
  for this device.

Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Cc: Kevin Wolf <kwolf@redhat.com>
Cc: Amit Shah <amit.shah@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: qemu-block@nongnu.org
Signed-off-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-01-10 05:56:58 +02:00
Stefan Hajnoczi
9ef9d40261 virtio-blk: suppress virtqueue kick during processing
The guest does not need to kick the virtqueue while we are processing
it.  This reduces the number of vmexits during periods of heavy I/O.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 20161201192652.9509-8-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-01-03 16:38:49 +00:00
Paolo Bonzini
9ffe337c08 virtio-blk: always use dataplane path if ioeventfd is active
Override start_ioeventfd and stop_ioeventfd to start/stop the
whole dataplane logic.  This has some positive side effects:

- no need anymore for virtio_add_queue_aio (i.e. a revert of
  commit 0ff841f6d1)

- no need anymore to switch from generic ioeventfd handlers to
  dataplane

It detects some errors better:

    $ qemu-system-x86_64 -object iothread,id=io \
          -drive id=null,file=null-aio://,if=none,format=raw \
          -device virtio-blk-pci,ioeventfd=off,iothread=io,drive=null
    qemu-system-x86_64: -device virtio-blk-pci,ioeventfd=off,iothread=io,drive=null:
    ioeventfd is required for iothread

while previously it would have started just fine.

Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-10-30 19:51:32 +02:00
Halil Pasic
5705653ff8 virtio: cleanup VMSTATE_VIRTIO_DEVICE
Now all the usages of the old version of VMSTATE_VIRTIO_DEVICE are gone,
so we can get rid of the conditionals, and the old macro.

Signed-off-by: Halil Pasic <pasic@linux.vnet.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-10-10 02:21:43 +03:00
Halil Pasic
977a117f78 virtio-blk: convert VMSTATE_VIRTIO_DEVICE
Use the new VMSTATE_VIRTIO_DEVICE macro.

Signed-off-by: Halil Pasic <pasic@linux.vnet.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-10-10 02:21:42 +03:00
Greg Kurz
20ea686a0c virtio-blk: handle virtio_blk_handle_request() errors
All these errors are caused by a buggy guest: QEMU should not exit.

With this patch, if virtio_blk_handle_request() detects a buggy request, it
marks the device as broken and returns an error to the caller so it takes
appropriate action.

In the case of virtio_blk_handle_vq(), we detach the request from the
virtqueue, free its allocated memory and stop popping new requests.
We don't need to bother about multireq since virtio_blk_handle_request()
errors out early and mrb.num_reqs == 0.

In the case of virtio_blk_dma_restart_bh(), we need to detach and free all
queued requests as well.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-10-10 01:16:59 +03:00
Greg Kurz
d14dde5ec7 virtio-blk: make some functions static
Some functions that were called from the dataplane code are now only used
locally:

virtio_blk_init_request()
virtio_blk_handle_request()
virtio_blk_submit_multireq()

since commit "03de2f527499 virtio-blk: do not use vring in dataplane", and

virtio_blk_free_request()

since commit "6aa46d8ff1ee virtio: move VirtQueueElement at the beginning
of the structs".

This patch converts them to static.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-10-10 01:16:58 +03:00
Stefan Hajnoczi
97b93c8ad2 virtio-blk: add missing virtio_detach_element() call
Make sure to unmap the scatter-gather list and decrement vq->inuse
before freeing requests in virtio_blk_reset().

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Ladi Prosek <lprosek@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-10-10 01:16:58 +03:00
Changlong Xie
b5c7ceaf4b virtio-blk: rename virtio_device_info to virtio_blk_info
The old one is confusing with @virtio_device_info in virtio.c,
so make it more appropriate.

Signed-off-by: Changlong Xie <xiecl.fnst@cn.fujitsu.com>
Message-id: 1470214147-32560-1-git-send-email-xiecl.fnst@cn.fujitsu.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-09-13 11:00:56 +01:00
Fam Zheng
27d1b87688 virtio-blk: Remove stale comment about draining
This is stale after commit 6e40b3bf (virtio-blk: Use blk_drain() to
drain IO requests), remove it.

Suggested-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Message-id: 1470278654-13525-3-git-send-email-famz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-08-05 09:59:06 +01:00
Fam Zheng
26307f6aa4 virtio-blk: Release s->rq queue at system_reset
At system_reset, there is no point in retrying the queued request,
because the driver that issued the request won't be around any more.

Analyzed-by: Laszlo Ersek <lersek@redhat.com>
Reported-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Message-id: 1470278654-13525-2-git-send-email-famz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-08-05 09:59:06 +01:00
Dr. David Alan Gilbert
bbded32c64 virtio-blk: Wrap in vmstate
Forcibly convert it to a vmstate wrapper;  proper conversion
comes later.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-07-21 20:44:20 +03:00
Fam Zheng
0ff841f6d1 virtio-blk: Call virtio_add_queue_aio
AIO based handler is more appropriate here because it will then
cooperate with bdrv_drained_begin/end. It is needed by the coming
revert patch.

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-21 20:44:19 +03:00
Kevin Wolf
8c39825218 block/qdev: Allow configuring rerror/werror with qdev properties
The rerror/werror policies are implemented in the devices, so that's
where they should be configured. In comparison to the old options in
-drive, the qdev properties are only added to those devices that
actually support them.

If the option isn't given (or "auto" is specified), the setting of the
BlockBackend is used for compatibility with the old options. For block
jobs, "auto" is the same as "enospc".

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2016-07-13 13:32:27 +02:00
Kevin Wolf
f6166a06ff block/qdev: Allow configuring WCE with qdev properties
As cache.writeback is a BlockBackend property and as such more related
to the guest device than the BlockDriverState, we already removed it
from the blockdev-add interface. This patch adds the new way to set it,
as a qdev property of the corresponding guest device.

For example: -drive if=none,file=test.img,node-name=img
             -device ide-hd,drive=img,write-cache=off

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2016-07-13 13:32:27 +02:00
Eric Blake
5def6b80e1 block: Switch transfer length bounds to byte-based
Sector-based limits are awkward to think about; in our on-going
quest to move to byte-based interfaces, convert max_transfer_length
and opt_transfer_length.  Rename them (dropping the _length suffix)
so that the compiler will help us catch the change in semantics
across any rebased code, and improve the documentation.  Use unsigned
values, so that we don't have to worry about negative values and
so that bit-twiddling is easier; however, we are still constrained
by 2^31 of signed int in most APIs.

When a value comes from an external source (iscsi and raw-posix),
sanitize the results to ensure that opt_transfer is a power of 2.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-07-05 16:46:25 +02:00
Eric Blake
24ce9a2026 block: Give nonzero result to blk_get_max_transfer_length()
Making all callers special-case 0 as unlimited is awkward,
and we DO have a hard maximum of BDRV_REQUEST_MAX_SECTORS given
our current block layer API limits.

In the case of scsi, this means that we now always advertise a
limit to the guest, even in cases where the underlying layers
previously use 0 for no inherent limit beyond the block layer.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-07-05 16:46:25 +02:00
Stefan Hajnoczi
2f2705908f virtio-blk: add num-queues device property
Multiqueue virtio-blk can be enabled as follows:

  qemu -device virtio-blk-pci,num-queues=8

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 1466511196-12612-8-git-send-email-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-06-28 13:08:32 +01:00
Stefan Hajnoczi
30d8bf6d17 virtio-blk: live migrate s->rq with multiqueue
Add a field for the virtqueue index when migrating the s->rq request
list.  The new field is only needed when num_queues > 1.  Existing QEMUs
are unaffected by this change and therefore virtio-blk migration stays
compatible.

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 1466511196-12612-6-git-send-email-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-06-28 13:08:32 +01:00
Stefan Hajnoczi
edaffd9f0b virtio-blk: associate request with a virtqueue
Multiqueue requires that each request knows to which virtqueue it
belongs.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 1466511196-12612-5-git-send-email-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-06-28 13:08:32 +01:00
Stefan Hajnoczi
b234cdda95 virtio-blk: tell dataplane which vq to notify
Let the virtio_blk_data_plane_notify() caller decide which virtqueue to
notify.  This will allow the function to be used with multiqueue.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 1466511196-12612-4-git-send-email-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-06-28 13:08:32 +01:00
Stefan Hajnoczi
84419863f7 virtio-blk: add VirtIOBlockConf->num_queues
The num_queues field is always 1 for the time being.  A later patch will
make it a configurable device property so that multiqueue can be
enabled.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 1466511196-12612-2-git-send-email-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-06-28 13:08:31 +01:00
Stefan Hajnoczi
17c42b1f6b Revert "virtio: sync the dataplane vring state to the virtqueue before virtio_save"
This reverts commit 10a06fd65f.

Dataplane has used the same virtqueue code as non-dataplane since
commits e24a47c5b7 ("virtio-scsi: do not
use vring in dataplane") and 03de2f5274
("virtio-blk: do not use vring in dataplane").  It is no longer
necessary to stop dataplane in order to sync state since there is no
duplicated virtqueue state.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Pavel Butsykin <pbutsykin@virtuozzo.com>
Message-id: 1466503331-9831-1-git-send-email-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-06-28 13:08:31 +01:00
Eric Blake
b5772fdde4 virtio: Switch to byte-based aio block access
Sector-based blk_aio_readv() and blk_aio_writev() should die; switch
to byte-based blk_aio_preadv() and blk_aio_pwritev() instead.

The trace is modified at the same time, and nb_sectors is now
unused.  Fix a comment typo while in the vicinity.

Signed-off-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-05-12 15:22:09 +02:00
Michael S. Tsirkin
8a2fad57eb virtio-blk: use aio handler for data plane
In addition to handling IO in vcpu thread and in io thread, dataplane
introduces yet another mode: handling it by AioContext.

This reuses the same handler as previous modes, which triggers races as
these were not designed to be reentrant.  Use a separate handler just
for aio, and disable regular handlers when dataplane is active.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-04-07 19:57:33 +03:00
Paolo Bonzini
eb41cf78fc virtio-blk: fix disabled mode
We must not call virtio_blk_data_plane_notify if dataplane is
disabled: we would hit a segmentation fault in notify_guest_bh as
s->guest_notifier has not been setup and is NULL.

Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-04-07 19:57:33 +03:00
Markus Armbruster
da34e65cb4 include/qemu/osdep.h: Don't include qapi/error.h
Commit 57cb38b included qapi/error.h into qemu/osdep.h to get the
Error typedef.  Since then, we've moved to include qemu/osdep.h
everywhere.  Its file comment explains: "To avoid getting into
possible circular include dependencies, this file should not include
any other QEMU headers, with the exceptions of config-host.h,
compiler.h, os-posix.h and os-win32.h, all of which are doing a
similar job to this file and are under similar constraints."
qapi/error.h doesn't do a similar job, and it doesn't adhere to
similar constraints: it includes qapi-types.h.  That's in excess of
100KiB of crap most .c files don't actually need.

Add the typedef to qemu/typedefs.h, and include that instead of
qapi/error.h.  Include qapi/error.h in .c files that need it and don't
get it now.  Include qapi-types.h in qom/object.h for uint16List.

Update scripts/clean-includes accordingly.  Update it further to match
reality: replace config.h by config-target.h, add sysemu/os-posix.h,
sysemu/os-win32.h.  Update the list of includes in the qemu/osdep.h
comment quoted above similarly.

This reduces the number of objects depending on qapi/error.h from "all
of them" to less than a third.  Unfortunately, the number depending on
qapi-types.h shrinks only a little.  More work is needed for that one.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
[Fix compilation without the spice devel packages. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-22 22:20:15 +01:00
Paolo Bonzini
03de2f5274 virtio-blk: do not use vring in dataplane
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-02-25 13:14:18 +02:00
Paolo Bonzini
2906cddfec virtio-blk: fix "disabled data plane" mode
In disabled mode, virtio-blk dataplane seems to be enabled, but flow
actually goes through the normal virtio path.  This patch simplifies a bit
the handling of disabled mode.  In disabled mode, virtio_blk_handle_output
might be called even if s->dataplane is not NULL.

This is a bit tricky, because the current check for s->dataplane will
always trigger, causing a continuous stream of calls to
virtio_blk_data_plane_start.  Unfortunately, these calls will not
do anything.  To fix this, set the "started" flag even in disabled
mode, and skip virtio_blk_data_plane_start if the started flag is true.
The resulting changes also prepare the code for the next patch, were
virtio-blk dataplane will reuse the same virtio_blk_handle_output function
as "regular" virtio-blk.

Because struct VirtIOBlockDataPlane is opaque in virtio-blk.c, we have
to move s->dataplane->started inside struct VirtIOBlock.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-02-25 13:14:18 +02:00
Paolo Bonzini
ab281c1781 virtio: introduce qemu_get/put_virtqueue_element
Move allocation to virtio functions also when loading/saving a
VirtQueueElement.  This will also let the load/save functions
keep backwards compatibility when the VirtQueueElement layout
is changed.

Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-02-06 20:44:08 +02:00
Paolo Bonzini
51b19ebe43 virtio: move allocation to virtqueue_pop/vring_pop
The return code of virtqueue_pop/vring_pop is unused except to check for
errors or 0.  We can thus easily move allocation inside the functions
and just return a pointer to the VirtQueueElement.

The advantage is that we will be able to allocate only the space that
is needed for the actual size of the s/g list instead of the full
VIRTQUEUE_MAX_SIZE items.  Currently VirtQueueElement takes about 48K
of memory, and this kind of allocation puts a lot of stress on malloc.
By cutting the size by two or three orders of magnitude, malloc can
use much more efficient algorithms.

The patch is pretty large, but changes to each device are testable
more or less independently.  Splitting it would mostly add churn.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2016-02-06 20:39:07 +02:00
Peter Maydell
80c71a241a block: Clean up includes
Clean up includes so that osdep.h is included first and headers
which it implies are not included manually.

This commit was created with scripts/clean-includes.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-01-20 13:36:23 +01:00
Stefan Hajnoczi
222565f65c block: replace IOV_MAX with BlockLimits.max_iov
Request merging must not result in a huge request that exceeds the
maximum number of iovec elements.  Use BlockLimits.max_iov instead of
hardcoding IOV_MAX.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-12-22 16:01:07 +08:00
Gonglei
49cffbc607 virtio-blk: trivial code optimization
1. avoid possible superflous checking
2. make code more robustness

["make code more robustness" refers to avoiding integer
underflows/overflows.
--Stefan]

Signed-off-by: Gonglei <arei.gonglei@huawei.com>
Message-id: 1447207166-12612-1-git-send-email-arei.gonglei@huawei.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-12-22 16:01:07 +08:00
Fam Zheng
a616fb75c2 virtio-blk: Drop x-data-plane option
The official way of enabling dataplane is through the "iothread"
property that references an iothread object created by "-object
iothread".  Since the old "x-data-plane=on" way now even crashes, it's
probably easier to just drop it:

$ qemu-system-x86_64 -drive file=null-co://,id=d0,if=none \
    -device virtio-blk-pci,drive=d0,x-data-plane=on

ERROR:/home/fam/work/qemu/qom/object.c:1515:
object_get_canonical_path_component: assertion failed: (obj->parent != NULL)
Aborted

Signed-off-by: Fam Zheng <famz@redhat.com>
Message-id: 1449485967-19240-1-git-send-email-famz@redhat.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2015-12-07 16:47:16 +00:00
Fam Zheng
466138dc68 virtio-blk: Move resetting of req->mr_next to virtio_blk_handle_rw_error
"werror=report" would free the req in virtio_blk_handle_rw_error, we
mustn't write to it in that case.

Reported-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Message-id: 1448239280-15025-1-git-send-email-famz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-11-24 09:27:49 +08:00
Fam Zheng
10f5a72f70 virtio-blk: Fix double completion for werror=stop
When a request R is absorbed by request M, it is appended to the
"mr_next" queue led by M, and is completed together with the completion
of M, in virtio_blk_rw_complete.

During DMA restart in virtio_blk_dma_restart_bh, requests in s->rq are
parsed and submitted again, possibly with a stale req->mr_next. It could
be a problem if the request merging in virtio_blk_handle_request hasn't
refreshed every mr_next pointer, in which case, virtio_blk_rw_complete
could walk through unexpected requests following the stale pointers.

Fix this by unsetting the pointer in virtio_blk_rw_complete. It is safe
because this req is either completed and freed right away, or it will be
restarted and parsed from scratch out of the vq later.

Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-11-17 18:35:57 +08:00