The virtio_queue_get_id() function is the lesser used duplicate of
virtio_get_queue_index(). Use the latter instead.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 1463767461-17922-1-git-send-email-stefanha@redhat.com
The previous patch dropped all op blockers from virtio-blk data plane.
The situation of virtio-scsi is exactly the same it can drop them too.
Signed-off-by: Fam Zheng <famz@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Message-id: 1463969978-24970-5-git-send-email-famz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
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.
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>
Add two missing checks for s->dataplane_fenced. In one case, QEMU
would skip injecting an IRQ due to a write to an uninitialized
EventNotifier's file descriptor.
In the second case, the dataplane_disabled field was used by mistake;
in fact after fixing this occurrence it is completely unused.
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>
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>
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>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
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>
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>
The next patch will make virtqueue_pop/vring_pop allocate memory for
the VirtQueueElement. In some cases (blk, scsi, gpu) the device wants
to extend VirtQueueElement with device-specific fields and, until now,
the place of the VirtQueueElement within the containing struct didn't
matter. When allocating the entire block in virtqueue_pop/vring_pop,
however, the containing struct must basically be a "subclass" of
VirtQueueElement, with the VirtQueueElement as the first field. Make
that the case for blk and scsi; gpu is already doing it.
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>
Make use of the BDS-BB removal and insertion notifiers to remove or set
up, respectively, virtio-scsi's op blockers.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
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>
Message-id: 1453832250-766-15-git-send-email-peter.maydell@linaro.org
Signed-off-by: Cao jin <caoj.fnst@cn.fujitsu.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <1452073066-28319-1-git-send-email-caoj.fnst@cn.fujitsu.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Make sure that we actually have a device when checking the aio
context. Otherwise guests could trigger QEMU crashes.
Signed-off-by: "Eugene (jno) Dvurechenski" <jno@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Message-Id: <1448549135-6582-2-git-send-email-jno@linux.vnet.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
When creating snapshot with the dataplane enabled, the snapshot file gets
not the actual state of virtqueue, because the current state is stored in
VirtIOBlockDataPlane. Therefore, before saving snapshot need to sync
the dataplane vring state to the virtqueue. The dataplane will resume its
work at the next notify virtqueue.
When snapshot loads with loadvm we get a message:
VQ 0 size 0x80 Guest index 0x15f5 inconsistent with Host index 0x0:
delta 0x15f5
error while loading state for instance 0x0 of device
'0000:00:08.0/virtio-blk'
Error -1 while loading VM state
to reproduce the error I used the following hmp commands:
savevm snap1
loadvm snap1
qemu parameters:
--enable-kvm -smp 4 -m 1024 -drive file=/var/lib/libvirt/images/centos6.4.qcow2,if=none,id=drive-virtio-disk0,format=qcow2,cache=none,aio=native -device virtio-blk-pci,scsi=off,bus=pci.0,addr=0x8,drive=drive-virtio-disk0,id=virtio-disk0 -set device.virtio-disk0.x-data-plane=on
Signed-off-by: Pavel Butsykin <pbutsykin@virtuozzo.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
Message-id: 1445859777-2982-1-git-send-email-den@openvz.org
CC: Stefan Hajnoczi <stefanha@redhat.com>
CC: "Michael S. Tsirkin" <mst@redhat.com>
CC: Kevin Wolf <kwolf@redhat.com>
CC: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Note: virtqueue_map already validates input
so virtio-scsi does not have to.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Simplify memory allocation by sticking with a single API. GSlice
is not that fast anyway (tcmalloc/jemalloc are better).
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Commit ef546f1275 ("virtio: add
feature checking helpers") introduced a helper __virtio_has_feature.
We don't want to use reserved identifiers, though, so let's
rename __virtio_has_feature to virtio_has_feature and virtio_has_feature
to virtio_vdev_has_feature.
Signed-off-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>
The VirtQueueElement struct is serialized during migration but the
in_sg[]/out_sg[] iovec arrays are not usable on the destination host
because the pointers are meaningless.
Use virtqueue_map_sg() to refresh in_sg[]/out_sg[] to valid pointers
based on in_addr[]/out_addr[] hwaddrs.
Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <1438262173-11546-2-git-send-email-stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
As only one place in virtio-scsi.c uses DEFINE_VIRTIO_SCSI_PROPERTIES
and DEFINE_VIRTIO_SCSI_FEATURES, there is no need to expose them. Inline
them into virtio-scsi.c to avoid wrongly use.
Signed-off-by: Shannon Zhao <zhaoshenglong@huawei.com>
Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-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>
Make features 64bit wide everywhere.
On migration a full 64bit guest_features field is sent if one of the
high bits is set, in addition to the lower 32bit guest_features field
which must stay for compatibility reasons. That way we send the lower
32 feature bits twice, but the code is simpler because we don't have
to split and compose the 64bit features into two 32bit fields.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
VIRTIO_PCI_QUEUE_MAX is not only used for pci, so rename it be generic.
Cc: Amit Shah <amit.shah@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
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>
So far virtio-scsi-device can't expose host features to guest while
using virtio-mmio because it doesn't set DEFINE_VIRTIO_SCSI_FEATURES on
backend or transport.
The host features belong to the backends while virtio-scsi-pci,
virtio-scsi-s390 and virtio-scsi-ccw set the DEFINE_VIRTIO_SCSI_FEATURES
on transports. But they already have the ability to forward property
accesses to the backend child. So if we move the host features to
backends, it doesn't break the backwards compatibility for them and
make host features work while using virtio-mmio.
Move DEFINE_VIRTIO_SCSI_FEATURES to the backend virtio-scsi. The
transports just sync the host features from backends.
Signed-off-by: Shannon Zhao <zhaoshenglong@huawei.com>
Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Hotplugging a scsi-disk may trigger the assertion in qemu_sgl_concat.
qemu-system-x86_64: qemu/hw/scsi/virtio-scsi.c:115: qemu_sgl_concat:
Assertion `skip == 0' failed.
This is introduced by commit 55783a55 (virtio-scsi: work around bug in
old BIOSes) which didn't check out_num when accessing out_sg[0].iov_len
(the same to in sg). For virtio_scsi_push_event, looking into out_sg
doesn't make sense because 0 req_size is intended.
Cc: qemu-stable@nongnu.org
[Cc'ing qemu-stable because 55783a55 did it too]
Signed-off-by: Fam Zheng <famz@redhat.com>
Message-Id: <1426233354-525-1-git-send-email-famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
cdb is now part of cmd, drop it from req.
There's also nothing to check using build assert now.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Commit "virtio-scsi: use standard-headers" added
cdb and sense into req/rep structures, which
breaks uses of sizeof for these structures,
since qemu adds its own arrays on top.
To fix, redefine CDB/sense field size to 0.
Reported-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
A bunch of fixes all over the place.
All of ACPI refactoring has been merged.
Legacy pci commands have been dropped.
virtio header cleanup
initial patches from virtio-1.0 branch
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge remote-tracking branch 'remotes/mst/tags/for_upstream' into staging
pci, pc, virtio fixes and cleanups
A bunch of fixes all over the place.
All of ACPI refactoring has been merged.
Legacy pci commands have been dropped.
virtio header cleanup
initial patches from virtio-1.0 branch
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
* remotes/mst/tags/for_upstream: (130 commits)
acpi: drop unused code
aml-build: comment fix
acpi-build: fix typo in comment
acpi: update generated files
vhost user:support vhost user nic for non msi guests
aml-build: fix build for glib < 2.22
acpi: update generated files
Makefile.target: binary depends on config-devices
acpi-test-data: update after pci rewrite
acpi, mem-hotplug: use PC_DIMM_SLOT_PROP in acpi_memory_plug_cb().
pci-hotplug-old: Has been dead for five major releases, bury
pci: Give a few helpers internal linkage
acpi: make build_*() routines static to aml-build.c
pc: acpi: remove not used anymore ssdt-[misc|pcihp].hex.generated blobs
pc: acpi-build: drop template patching and create PCI bus tree dynamically
tests: ACPI: update pc/SSDT.bridge due to new alg of PCI tree creation
pc: acpi-build: simplify PCI bus tree generation
tests: add ACPI blobs for qemu with bridge cases
tests: bios-tables-test: add support for testing bridges
tests: ACPI test blobs update due to PCI0._CRS changes
...
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Conflicts:
hw/pci/pci-hotplug-old.c
s->blocker is really only used in hw/scsi/virtio-scsi.c; the only places
where it is used in hw/scsi/virtio-scsi-dataplane.c is when it is
allocated and when it is freed. That does not make a whole lot of sense
(and is actually wrong because this leads to s->blocker potentially
being NULL when blk_op_block_all() is called in virtio-scsi.c), so move
the allocation and destruction of s->blocker to the device realization
and unrealization in virtio-scsi.c, respectively.
Case in point:
$ echo -e 'eject drv\nquit' | \
x86_64-softmmu/qemu-system-x86_64 \
-monitor stdio -machine accel=qtest -display none \
-object iothread,id=thr -device virtio-scsi-pci,iothread=thr \
-drive if=none,file=test.qcow2,format=qcow2,id=drv \
-device scsi-cd,drive=drv
Without this patch:
(qemu) eject drv
[1] 10102 done
10103 segmentation fault (core dumped)
With this patch:
(qemu) eject drv
Device 'drv' is busy: block device is in use by data plane
(qemu) quit
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-Id: <1425057113-26940-1-git-send-email-mreitz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
It's not safe to call blk_set_aio_context from outside BQL because of
the bdrv_drain_all there. Let's put it in the hotplug callback which
will be called by qdev device realization for each scsi device attached
to the bus.
Signed-off-by: Fam Zheng <famz@redhat.com>
Message-Id: <1423969591-23646-3-git-send-email-famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Add a helper function for checking whether a bit is set in the guest
features for a vdev as well as one that works on a feature bit set.
Convert code that open-coded this: It cleans up the code and makes it
easier to extend the guest feature bits.
Signed-off-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>
Several places check against the feature bit number instead of against
the feature bit. Fix them.
Cc: qemu-stable@nongnu.org
Reported-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Signed-off-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>
g_new(T, n) is neater than g_malloc(sizeof(T) * n). It's also safer,
for two reasons. One, it catches multiplication overflowing size_t.
Two, it returns T * rather than void *, which lets the compiler catch
more type errors.
This commit only touches allocations with size arguments of the form
sizeof(T).
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Old BIOSes left some padding by mistake after the req_size/resp_size.
New QEMU does not like it, thinking it is a bidirectional command.
As a workaround, we can check if the ANY_LAYOUT bit is set; if not, we
always consider the first buffer as the virtio-scsi request/response,
because, back when QEMU did not support ANY_LAYOUT, it expected the
payload to start at the second element of the iovec.
This can show up during migration.
Cc: qemu-stable@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
We need to count the ctrlq and eventq, and also cleanup before
returning. Besides, the format string should be unsigned.
The number could never be less than zero.
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The local variable "type" in virtio_scsi_handle_ctl represents the tmf
command type from the guest and it has the same meaning as the
req->req.tmf.type. However, before the invoking of virtio_scsi_parse_req
the req->req.tmf.type doesn't has the correct value(just initialized to
zero). Therefore, we need to use the "type" variable to judge the case.
Cc: qemu-stable@nongnu.org
Signed-off-by: Bin Wu <wu.wubin@huawei.com>
[Actually make it compile, "type" must be uint32_t in order to pass
it to virtio_tswap32s. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
If req->resp.cmd.status is not GOOD, the address of sense for
qemu_iovec_from_buf should be modified from &req->resp to sense.
Cc: qemu-stable@nongnu.org
Signed-off-by: Ting Wang <kathy.wangting@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
We need this to protect dataplane thread from race conditions with block
jobs until the latter is made dataplane-safe.
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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>
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
scsi_req_continue can complete the request and cause the VirtIOSCSIReq
to be freed. Fetch req->sreq just once to avoid the bug.
Reported-by: Richard Jones <rjones@redhat.com>
Tested-by: Richard Jones <rjones@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
For VIRTIO_SCSI_T_TMF_ABORT_TASK and VIRTIO_SCSI_T_TMF_ABORT_TASK_SET,
use scsi_req_cancel_async to start the cancellation.
Because each tmf command may cancel multiple requests, we need to use a
counter to track the number of remaining requests we still need to wait
for.
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Queue the popped requests while calling
virtio_scsi_handle_cmd_req_prepare(), then submit them after all
prepared.
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Mechanical change, in preparation for bdrv_io_plug/bdrv_io_unplug.
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Similar to virtio-blk-dataplane, we stop the iothread while migration
starts and restart it when migration finishes.
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This enables the virtio-scsi-dataplane code by setting the iothread
in virtio-scsi device, and makes any function that is called by
back from dataplane to cooperate with the caller: they need to be
vring/iothread aware when handling the requests and using scsi devices
on the bus.
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>