Commit Graph

29 Commits

Author SHA1 Message Date
Michael S. Tsirkin 907eb3e5b6 virtio-blk: switch to standard-headers
Drop duplicated code. Minor codechanges were required
as geometry is a sub-structure now.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Thomas Huth <thuth@linux.vnet.ibm.com>
2015-02-26 13:04:04 +01:00
Peter Lieven c99495ac1b virtio-blk: add a knob to disable request merging
this adds a knob to disable request merging for debugging or benchmarks if dedired.

Signed-off-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-02-06 17:24:21 +01:00
Peter Lieven 95f7142abc virtio-blk: introduce multiread
this patch finally introduces multiread support to virtio-blk. While
multiwrite support was there for a long time, read support was missing.

The complete merge logic is moved into virtio-blk.c which has
been the only user of request merging ever since. This is required
to be able to merge chunks of requests and immediately invoke callbacks
for those requests. Secondly, this is required to switch to
direct invocation of coroutines which is planned at a later stage.

The following benchmarks show the performance of running fio with
4 worker threads on a local ram disk. The numbers show the average
of 10 test runs after 1 run as warmup phase.

              |        4k        |       64k        |        4k
MB/s          | rd seq | rd rand | rd seq | rd rand | wr seq | wr rand
--------------+--------+---------+--------+---------+--------+--------
master        | 1221   | 1187    | 4178   | 4114    | 1745   | 1213
multiread     | 1829   | 1189    | 4639   | 4110    | 1894   | 1216

Signed-off-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-02-06 17:24:21 +01:00
Peter Lieven d901f3c457 hw/virtio-blk: add a constant for max number of merged requests
As it was not obvious (at least for me) where the 32 comes from;
add a constant for it.

Signed-off-by: Peter Lieven <pl@kamp.de>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-02-06 17:24:21 +01:00
Fam Zheng 75344fa4c5 virtio-blk: Pass req to virtio_blk_handle_scsi_req
In preparation for calling blk_aio_ioctl. Also make the function static
as no other files need it.

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-01-23 18:17:05 +01:00
Markus Armbruster 4be746345f hw: Convert from BlockDriverState to BlockBackend, mostly
Device models should access their block backends only through the
block-backend.h API.  Convert them, and drop direct includes of
inappropriate headers.

Just four uses of BlockDriverState are left:

* The Xen paravirtual block device backend (xen_disk.c) opens images
  itself when set up via xenbus, bypassing blockdev.c.  I figure it
  should go through qmp_blockdev_add() instead.

* Device model "usb-storage" prompts for keys.  No other device model
  does, and this one probably shouldn't do it, either.

* ide_issue_trim_cb() uses bdrv_aio_discard() instead of
  blk_aio_discard() because it fishes its backend out of a BlockAIOCB,
  which has only the BlockDriverState.

* PC87312State has an unused BlockDriverState[] member.

The next two commits take care of the latter two.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-10-20 14:02:25 +02:00
Markus Armbruster 2a30307f70 virtio-blk: Rename VirtIOBlkConf variables to conf
This is consistent with how VirtIOFOOConf variables are named
elsewhere, and makes blk available for BlockBackend variables.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-10-20 14:02:21 +02:00
Markus Armbruster f75167313c virtio-blk: Drop redundant VirtIOBlock member conf
Commit 12c5674 turned it into a pointer to member blk.conf.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Benoît Canet <benoit.canet@nodalink.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-10-20 13:48:28 +02:00
Fam Zheng 52b53c04fa block: Always compile virtio-blk dataplane
Dataplane doesn't depend on linux-aio any more, so we don't need the
compiling condition now.

Configure options are kept but just print a message.

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 1410329871-28885-4-git-send-email-famz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22 11:39:51 +01:00
Benoît Canet 5e5a94b605 block: Extract the block accounting code
The plan is to add new accounting metrics (latency, invalid requests, failed
requests, queue depth) and block.c is overpopulated so it will be better to work
in a separate module.

Moreover the long term plan is to have statistics in each of the BDS of the graph
for metrology purpose; this means that the device model statistics must move from
the topmost BDS to the device model.

So we need to decouple the statistic code from BlockDriverState.

This is another argument for the extraction of the code in a separate module.

CC: Kevin Wolf <kwolf@redhat.com>
CC: Stefan Hajnoczi <stefanha@redhat.com>
CC: Max Reitz <mreitz@redhat.com>
CC: Eric Blake <eblake@redhat.com>
CC: Benoit Canet <benoit@irqsave.net>
CC: Fam Zheng <famz@redhat.com>
CC: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
CC: Paolo Bonzini <pbonzini@redhat.com>

Signed-off-by: Benoît Canet <benoit.canet@nodalink.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-09-10 10:41:29 +02:00
Stefan Hajnoczi f897bf751f virtio-blk: embed VirtQueueElement in VirtIOBlockReq
The memory allocation between hw/block/virtio-blk.c,
hw/block/dataplane/virtio-blk.c, and hw/virtio/dataplane/vring.c is
messy.  Structs are allocated in different files than they are freed in.
This is risky and makes memory leaks easier.

Embed VirtQueueElement in VirtIOBlockReq to reduce the amount of memory
allocation we need to juggle.  This also makes vring.c and virtio.c
slightly more similar.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-07-14 12:03:20 +02:00
Ming Lei 85d1277e66 virtio: move common virtio properties to bus class device
The two common virtio features can be defined per bus, so move all
into bus class device to make code more clean.

As discussed with cornelia, s390-virtio-blk doesn't support
the two features at all, so keep s390-virtio as it.

Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> #for s390 ccw
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

MST: rebase and resolve conflicts
2014-07-06 09:13:54 +03:00
Stefan Hajnoczi 32a877e405 virtio-blk: move qdev properties into virtio-blk.c
There is no need to make DEFINE_VIRTIO_BLK_PROPERTIES() public.  Inline
it into virtio-blk.c so it cannot be used by mistake from other source
files.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
2014-07-01 09:15:02 +02:00
Stefan Hajnoczi f7fedda84a virtio-blk: drop virtio_blk_set_conf()
This function is no longer used since parent objects now use child
aliases to set the VirtIOBlkConf directly.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
2014-07-01 09:15:02 +02:00
Stefan Hajnoczi ee512c6f21 virtio-blk: move x-data-plane qdev property to virtio-blk.h
Move the x-data-plane property.  Originally it was outside since not
every transport may wish to support dataplane.  But that makes little
sense when we have a dedicated CONFIG_VIRTIO_BLK_DATA_PLANE ifdef
already.

This move makes it easier to switch to property aliases in the next
patch.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
2014-07-01 09:15:02 +02:00
Stefan Hajnoczi dc80ca6cd6 virtio-blk: avoid qdev property definition duplication
It becomes unwiedly to duplicate all virtio-blk qdev property
definitions due to an #ifdef.  The C preprocessor syntax makes it a
little hard to resolve this cleanly but we can extract the #ifdef and
call a macro it defines later.

Avoiding duplication is important since it will only get worse when we
move the x-data-plane qdev property here too.  We'd have a combinatorial
explosion since x-data-plane has its own #ifdef.

Suggested-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
2014-07-01 09:15:02 +02:00
Fam Zheng fee65db771 virtio-blk: Export request handling functions to dataplane
So that dataplane can use virtio_blk_handle_request and
virtio_submit_multiwrite.

Signed-off-by: Fam Zheng <famz@redhat.com>
Tested-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-06-27 18:20:35 +02:00
Fam Zheng bf4bd461b4 virtio-blk: Make request completion function virtual
virtio_blk_req_complete will call VirtIOBlock.complete_request() to push
data and notify guest. No functional change.

Later, this will allow dataplane to provide it's own (vring_) version.

Signed-off-by: Fam Zheng <famz@redhat.com>
Tested-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-06-27 18:20:32 +02:00
Fam Zheng 827805a249 virtio-blk: Convert VirtIOBlockReq.out to structrue
The virtio code currently assumes that the outhdr is in its own iovec.
This is not guaranteed by the spec, so we should relax this assumption.

Convert the VirtIOBlockReq.out field to structrue so that we can use
iov_to_buf and then discard the header from the beginning of iovec.

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-06-27 18:18:25 +02:00
Fam Zheng eddb102e86 virtio-blk: Use VirtIOBlockReq.in to drop VirtIOBlockReq.inhdr
In current virtio spec, inhdr is a single byte, and is unlikely to
change for both functionality and compatibility considerations.
Non-dataplane uses .in, and we are on the way to converge them. So
let's unify it to get cleaner code.

Remove .inhdr and use .in.

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-06-27 18:18:23 +02:00
Fam Zheng 04af2d70c5 virtio-blk: Replace VirtIOBlockRequest with VirtIOBlockReq
Field "inhdr" is added temporarily for a more mechanical change, and
will be dropped in the next commit.

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-06-27 18:18:20 +02:00
Fam Zheng 671ec3f056 virtio-blk: Convert VirtIOBlockReq.elem to pointer
This will make converging with dataplane code easier.

Add virtio_blk_free_request to handle the freeing of request internal
fields.

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-06-27 18:18:13 +02:00
Fam Zheng 09f6458770 virtio-blk: Move VirtIOBlockReq to header
For later reusing by dataplane code.

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-06-27 18:17:59 +02:00
Fam Zheng 5a05cbeeaa virtio-blk: Factor out virtio_blk_handle_scsi_req from virtio_blk_handle_scsi
The common logic to process a scsi request in a VirtQueueElement is
extracted to a function to share with dataplane.

This makes VirtIOBlockReq.scsi unused, so drop it.

Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-06-04 09:56:12 +02:00
Stefan Hajnoczi 48ff269272 dataplane: replace internal thread with IOThread
Today virtio-blk dataplane uses a 1:1 device-per-thread model.  Now that
IOThreads have been introduced we can generalize this to N:M devices per
threads.

This patch drops thread code from dataplane in favor of running inside
an IOThread AioContext.

As a bonus we solve the case where a guest keeps submitting I/O requests
while dataplane is trying to stop.  Previously the dataplane thread
would continue to process requests until the request gave it a break.
Now we can shut down in bounded time thanks to
aio_context_acquire/release.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-03-13 14:42:24 +01:00
Paolo Bonzini ef5bc96268 virtio-blk: do not relay a previous driver's WCE configuration to the current
The following sequence happens:
- the SeaBIOS virtio-blk driver does not support the WCE feature, which
causes QEMU to disable writeback caching

- the Linux virtio-blk driver resets the device, finds WCE is available
but writeback caching is disabled; tells block layer to not send cache
flush commands

- the Linux virtio-blk driver sets the DRIVER_OK bit, which causes
writeback caching to be re-enabled, but the Linux virtio-blk driver does
not know of this side effect and cache flushes remain disabled

The bug is at the third step.  If the guest does know about CONFIG_WCE,
QEMU should ignore the WCE feature's state.  The guest will control the
cache mode solely using configuration space.  This change makes Linux
do flushes correctly, but Linux will keep SeaBIOS's writethrough mode.

Hence, whenever the guest is reset, the cache mode of the disk should
be reset to whatever was specified in the "-drive" option.  With this
change, the Linux virtio-blk driver finds that writeback caching is
enabled, and tells the block layer to send cache flush commands
appropriately.

Reported-by: Rusty Russell <rusty@au1.ibm.com
Cc: qemu-stable@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-09-20 19:27:48 +02:00
Stefan Hajnoczi 84db52d059 dataplane: enable virtio-blk x-data-plane=on live migration
Although the dataplane thread does not cooperate with dirty memory
logging yet it's fairly easy to temporarily disable dataplane during
live migration.  This way virtio-blk can live migrate when
x-data-plane=on.

The dataplane thread will restart after migration is cancelled or if the
guest resuming virtio-blk operation after migration completes.

Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-07-29 17:19:07 +02:00
KONRAD Frederic f574fa8b07 virtio: fix broken aliases.
This fix the broken aliases, by renaming the devices.

So: * virtio-blk => virtio-blk-device.
    * virtio-balloon => virtio-balloon-device.
    * virtio-scsi => virtio-scsi-device.

All virtio-*-pci, virtio-*-s390, virtio-*-ccw didn't change.

Signed-off-by: KONRAD Frederic <fred.konrad@greensocs.com>
Message-id: 1365501888-14602-1-git-send-email-fred.konrad@greensocs.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-04-15 10:22:04 -05:00
Paolo Bonzini 0d09e41a51 hw: move headers to include/
Many of these should be cleaned up with proper qdev-/QOM-ification.
Right now there are many catch-all headers in include/hw/ARCH depending
on cpu.h, and this makes it necessary to compile these files per-target.
However, fixing this does not belong in these patches.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-04-08 18:13:10 +02:00