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path: root/include/hw/virtio/virtio.h
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2017-05-25virtio_net: Bypass backends for MTU feature negotiationMaxime Coquelin
This patch adds a new internal "x-mtu-bypass-backend" property to bypass backends for MTU feature negotiation. When this property is set, the MTU feature is negotiated as soon as supported by the guest and a MTU value is set via the host_mtu parameter. In case the backend advertises the feature (e.g. DPDK's vhost-user backend), the feature negotiation is propagated down to the backend. When this property is not set, the backend has to support the MTU feature for its negotiation to succeed. For compatibility purpose, this property is disabled for machine types v2.9 and older. Cc: Aaron Conole <aconole@redhat.com> Suggested-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com> Reviewed-by: Vlad Yasevich <vyasevic@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-03-29virtio: fix vring_align() on 64-bit windowsAndrew Baumann
long is 32-bits on 64-bit windows, which caused the top half of the address to be truncated; this patch changes it to use the QEMU_ALIGN_UP macro which does not suffer the same problem Signed-off-by: Andrew Baumann <Andrew.Baumann@microsoft.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Stefan Weil <sw@weilnetz.de> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
2017-02-17virtio: add MemoryListener to cache ring translationsPaolo Bonzini
The cached translations are RCU-protected to allow efficient use when processing virtqueues. Reviewed-by: Stefan Hajnoczi <stefanha@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>
2017-02-17virtio: Report real progress in VQ aio poll handlerFam Zheng
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>
2017-02-01virtio: make virtio_should_notify staticPaolo Bonzini
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: Stefan Hajnoczi <stefanha@redhat.com>
2017-01-20virtio-ccw: fix ring sizingMichael S. Tsirkin
Current code seems to assume ring size is always decreased but this is not required by spec: what spec says is just that size can not exceed the maximum. Fix it up. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Message-Id: <1484256243-1982-1-git-send-email-mst@redhat.com> Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2017-01-10virtio: Introduce virtqueue_drop_all procedureYuri Benditovich
Add procedure for fast drop of queued packets, acting like pop and push without mapping the buffers into memory. Signed-off-by: Yuri Benditovich <yuri.benditovich@daynix.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-01-10net: Add virtio queue interface to update used index from vring stateYuri Benditovich
Bring virtio queue to correct internal state for host-to-guest operations when vhost is temporary stopped. Signed-off-by: Yuri Benditovich <yuri.benditovich@daynix.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-01-10virtio: convert to use DMA apiJason Wang
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>
2016-11-18virtio: set ISR on dataplane notificationsPaolo Bonzini
Dataplane has been omitting forever the step of setting ISR when an interrupt is raised. This caused little breakage, because the specification actually says that ISR may not be updated in MSI mode. Some versions of the Windows drivers however didn't clear MSI mode correctly, and proceeded using polling mode (using ISR, not the used ring index!) for crashdump and hibernation. If it were just crashdump and hibernation it would not be a big deal, but recent releases of Windows do not really shut down, but rather log out and hibernate to make the next startup faster. Hence, this manifested as a more serious hang during shutdown with e.g. Windows 8.1 and virtio-win 1.8.0 RPMs. Newer versions fixed this, while older versions do not use MSI at all. The failure has always been there for virtio dataplane, but it became visible after commits 9ffe337 ("virtio-blk: always use dataplane path if ioeventfd is active", 2016-10-30) and ad07cd6 ("virtio-scsi: always use dataplane path if ioeventfd is active", 2016-10-30) made virtio-blk and virtio-scsi always use the dataplane code under KVM. The good news therefore is that it was not a bug in the patches---they were doing exactly what they were meant for, i.e. shake out remaining dataplane bugs. The fix is not hard, so it's worth arranging for the broken drivers. The virtio_should_notify+event_notifier_set pair that is common to virtio-blk and virtio-scsi dataplane is replaced with a new public function virtio_notify_irqfd that also sets ISR. The irqfd emulation code now need not set ISR anymore, so virtio_irq is removed. Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Tested-by: Farhan Ali <alifm@linux.vnet.ibm.com> Tested-by: Alex Williamson <alex.williamson@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>
2016-11-18virtio: introduce grab/release_ioeventfd to fix vhostPaolo Bonzini
Following the recent refactoring of virtio notifiers [1], more specifically the patch ed08a2a0b ("virtio: use virtio_bus_set_host_notifier to start/stop ioeventfd") that uses virtio_bus_set_host_notifier [2] by default, core virtio code requires 'ioeventfd_started' to be set to true/false when the host notifiers are configured. When vhost is stopped and started, however, there is a stop followed by another start. Since ioeventfd_started was never set to true, the 'stop' operation triggered by virtio_bus_set_host_notifier() will not result in a call to virtio_pci_ioeventfd_assign(assign=false). This leaves the memory regions with stale notifiers and results on the next start triggering the following assertion: kvm_mem_ioeventfd_add: error adding ioeventfd: File exists Aborted This patch reintroduces (hopefully in a cleaner way) the concept that was present with ioeventfd_disabled before the refactoring. When ioeventfd_grabbed>0, ioeventfd_started tracks whether ioeventfd should be enabled or not, but ioeventfd is actually not started at all until vhost releases the host notifiers. [1] http://lists.nongnu.org/archive/html/qemu-devel/2016-10/msg07748.html [2] http://lists.nongnu.org/archive/html/qemu-devel/2016-10/msg07760.html Reported-by: Felipe Franciosi <felipe@nutanix.com> Reported-by: Christian Borntraeger <borntraeger@de.ibm.com> Reported-by: Alex Williamson <alex.williamson@redhat.com> Fixes: ed08a2a0b ("virtio: use virtio_bus_set_host_notifier to start/stop ioeventfd") Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru> Tested-by: Farhan Ali <alifm@linux.vnet.ibm.com> Tested-by: Alex Williamson <alex.williamson@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>
2016-11-15virtio: drop virtio_queue_get_ring_{size,addr}()Greg Kurz
These are not used anymore. Signed-off-by: Greg Kurz <groug@kaod.org> 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>
2016-11-15virtio: allow per-device-class legacy featuresMichael S. Tsirkin
Legacy features are those that transitional devices only expose on the legacy interface. Allow different ones per device class. Cc: qemu-stable@nongnu.org # dependency for the next patch Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2016-11-15virtio: make virtqueue_alloc_element staticLadi Prosek
The function does not fully initialize the returned VirtQueueElement and should be used only internally from the virtio module. Signed-off-by: Ladi Prosek <lprosek@redhat.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>
2016-11-15virtio: rename virtqueue_discard to virtqueue_unpopLadi Prosek
The function undoes the effect of virtqueue_pop and doesn't do anything destructive or irreversible so virtqueue_unpop is a more fitting name. Signed-off-by: Ladi Prosek <lprosek@redhat.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>
2016-10-30virtio: inline virtio_queue_set_host_notifier_fd_handlerPaolo Bonzini
Of the three possible parameter combinations for virtio_queue_set_host_notifier_fd_handler: - assign=true/set_handler=true is only called from virtio_device_start_ioeventfd - assign=false/set_handler=false is called from set_host_notifier_internal but it only does something when reached from virtio_device_stop_ioeventfd_impl; otherwise there is no EventNotifier set on qemu_get_aio_context(). - assign=true/set_handler=false is called from set_host_notifier_internal, but it is not doing anything: with the new start_ioeventfd and stop_ioeventfd methods, there is never an EventNotifier set on qemu_get_aio_context() at this point. This is enforced by the assertion in virtio_bus_set_host_notifier. 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>
2016-10-30Revert "virtio: Introduce virtio_add_queue_aio"Paolo Bonzini
This reverts commit 872dd82c83745a603d2e07a03d34313eb6467ae4. virtio_add_queue_aio is unused. Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> 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>
2016-10-30virtio: introduce virtio_device_ioeventfd_enabledPaolo Bonzini
This will be used to forbid iothread configuration when the proxy does not allow using ioeventfd. To simplify the implementation, change the direction of the ioeventfd_disabled callback too. Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> 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>
2016-10-30virtio: add start_ioeventfd and stop_ioeventfd to VirtioDeviceClassPaolo Bonzini
Allow customization of the start and stop of ioeventfd. This will allow direct start of dataplane without passing through the default ioeventfd handlers, which in turn allows using the dataplane logic instead of virtio_add_queue_aio. It will also enable some code simplification, because the sole entry point to ioeventfd setup will be virtio_bus_set_host_notifier. Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> 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>
2016-10-30virtio/migration: Add VMStateDescription to VirtioDeviceClassDr. David Alan Gilbert
Provide a vmsd pointer for VirtIO devices to use instead of the load/save methods. We'll eventually kill off the load/save methods. Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-10-10virtio: cleanup VMSTATE_VIRTIO_DEVICEHalil Pasic
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>
2016-10-10virtio: prepare change VMSTATE_VIRTIO_DEVICE macroHalil Pasic
In most cases the functions passed to VMSTATE_VIRTIO_DEVICE only call the virtio_load and virtio_save wrappers. Some include some pre- and post- massaging too. The massaging is better expressed as such in the VMStateDescription. Let us prepare for changing the semantic of the VMSTATE_VIRTIO_DEVICE macro so that it is more similar to the other VMSTATE_*_DEVICE macros in a sense that it is a field definition. The preprocessor conditionals are going to be removed as soon as every usage is converted to the new semantic. 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>
2016-10-10virtio: add virtio_detach_element()Stefan Hajnoczi
During device reset or similar situations a VirtQueueElement needs to be freed without pushing it onto the used ring or rewinding the virtqueue. Extract a new function to do this. Later patches add virtio_detach_element() calls to existing device so that scatter-gather lists are unmapped and vq->inuse goes back to zero during device reset. Currently some devices don't bother and simply call g_free(elem) which is not a clean way to throw away a VirtQueueElement. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Acked-by: Greg Kurz <groug@kaod.org> Reviewed-by: Ladi Prosek <lprosek@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-09-23virtio: stop virtqueue processing if device is brokenStefan Hajnoczi
QEMU prints an error message and exits when the device enters an invalid state. Terminating the process is heavy-handed. The guest may still be able to function even if there is a bug in a virtio guest driver. Moreover, exiting is a bug in nested virtualization where a nested guest could DoS other nested guests by killing a pass-through virtio device. I don't think this configuration is possible today but it is likely in the future. If the broken flag is set, do not process virtqueues or write back used descriptors. The broken flag can be cleared again by resetting the device. Signed-off-by: Stefan Hajnoczi <stefanha@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> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2016-09-09virtio: add virtqueue_rewind()Stefan Hajnoczi
virtqueue_discard() requires a VirtQueueElement but virtio-balloon does not migrate its in-use element. Introduce a new function that is similar to virtqueue_discard() but doesn't require a VirtQueueElement. This will allow virtio-balloon to access element again after migration with the usual proviso that the guest may have modified the vring since last time. Cc: Michael S. Tsirkin <mst@redhat.com> Cc: Roman Kagan <rkagan@virtuozzo.com> Cc: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Ladi Prosek <lprosek@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-07-21virtio: Migration helper function and macroDr. David Alan Gilbert
To make conversion of virtio devices to VMState simple at first add a helper function for the simple virtio_save case and a helper macro that defines the VMState structure. These will probably go away or change as more of the virtio code gets converted. 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>
2016-07-21virtio: Introduce virtio_add_queue_aioFam Zheng
Using this function instead of virtio_add_queue marks the vq as aio based. This differentiation will be useful in later patches. Distinguish between virtqueue processing in the iohandler context and main loop AioContext. iohandler context is isolated from AioContexts and therefore does not run during aio_poll(). 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>
2016-07-21virtio: Add typedef for handle_outputFam Zheng
The function pointer signature has been repeated a few times, using a typedef may make coding easier. Signed-off-by: Fam Zheng <famz@redhat.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> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-12Clean up ill-advised or unusual header guardsMarkus Armbruster
Cleaned up with scripts/clean-header-guards.pl. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Richard Henderson <rth@twiddle.net>
2016-06-07virtio: drop duplicate virtio_queue_get_id() functionStefan Hajnoczi
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
2016-04-07virtio: merge virtio_queue_aio_set_host_notifier_handler with ↵Paolo Bonzini
virtio_queue_set_aio Eliminating the reentrancy is actually a nice thing that we can do with the API that Michael proposed, so let's make it first class. This also hides the complex assign/set_handler conventions from callers of virtio_queue_aio_set_host_notifier_handler, which in fact was always called with assign=true. 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>
2016-04-07virtio: add aio handlerMichael S. Tsirkin
In addition to handling IO in vcpu thread and in io thread, blk dataplane introduces yet another mode: handling it by AioContext. Currently, this reuses the same handler as previous modes, which triggers races as these were not designed to be reentrant. Add instead a separate handler just for aio; this will make it possible to 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>
2016-04-07virtio: make virtio_queue_notify_vq staticPaolo Bonzini
Acked-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>
2016-02-25virtio: export vring_notify as virtio_should_notifyPaolo Bonzini
Virtio dataplane needs to trigger the irq manually through the guest notifier. Export virtio_should_notify so that it can be used around event_notifier_set. 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: Cornelia Huck <cornelia.huck@de.ibm.com> Reviewed-by: Fam Zheng <famz@redhat.com> Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-02-25virtio: add AioContext-specific function for host notifiersPaolo Bonzini
This is used to register ioeventfd with a dataplane thread. 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>
2016-02-18vhost-user interrupt management fixesVictor Kaplansky
Since guest_mask_notifier can not be used in vhost-user mode due to buffering implied by unix control socket, force use_mask_notifier on virtio devices of vhost-user interfaces, and send correct callfd to the guest at vhost start. Using guest_notifier_mask function in vhost-user case may break interrupt mask paradigm, because mask/unmask is not really done when returning from guest_notifier_mask call, instead message is posted in a unix socket, and processed later. Add an option boolean flag 'use_mask_notifier' to disable the use of guest_notifier_mask in virtio pci. Signed-off-by: Didier Pallard <didier.pallard@6wind.com> Signed-off-by: Victor Kaplansky <victork@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-02-06virtio: introduce virtqueue_alloc_elementPaolo Bonzini
Allocate the arrays for in_addr/out_addr/in_sg/out_sg outside the VirtQueueElement. For now, virtqueue_pop and vring_pop keep allocating a very large VirtQueueElement. 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>
2016-02-06virtio: introduce qemu_get/put_virtqueue_elementPaolo Bonzini
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>
2016-02-06virtio: move allocation to virtqueue_pop/vring_popPaolo Bonzini
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>
2015-10-29virtio: drop virtqueue_map_sgMichael S. Tsirkin
Deprecated in favor of virtqueue_map. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Igor Mammedov <imammedo@redhat.com>
2015-10-29virtio: introduce virtio_mapMichael S. Tsirkin
virtio_map_sg currently fails if one of the entries it's mapping is contigious in GPA but not HVA address space. Introduce virtio_map which handles this by splitting sg entries. This new API generally turns out to be a good idea since it's harder to misuse: at least in one case the existing one was used incorrectly. This will still fail if there's no space left in the sg, but luckily max queue size in use is currently 256, while max sg size is 1024, so we should be OK even is all entries happen to cross a single DIMM boundary. Won't work well with very small DIMM sizes, unfortunately: e.g. this will fail with 4K DIMMs where a single request might span a large number of DIMMs. Let's hope these are uncommon - at least we are not breaking things. Note: virtio-scsi calls virtio_map_sg on data loaded from network, and validates input, asserting on failure. Copy the validating code here - it will be dropped from virtio-scsi in a follow-up patch. Reported-by: Igor Mammedov <imammedo@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Igor Mammedov <imammedo@redhat.com>
2015-10-01virtio: introduce virtqueue_discard()Jason Wang
This patch introduces virtqueue_discard() to discard a descriptor and unmap the sgs. This will be used by the patch that will discard descriptor when packet is truncated. Cc: Michael S. Tsirkin <mst@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>
2015-09-10virtio: avoid leading underscores for helpersCornelia Huck
Commit ef546f1275f6563e8934dd5e338d29d9f9909ca6 ("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>
2015-08-05virtio: fix 1.0 virtqueue migrationJason Wang
1.0 does not requires physically-contiguous pages layout for a virtqueue. So we could not infer avail and used from desc. This means we need to migrate vring.avail and vring.used when host support virtio 1.0. This fixes malfunction of virtio 1.0 device after migration. Cc: Michael S. Tsirkin <mst@redhat.com> Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Cc: Dr. David Alan Gilbert <dgilbert@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>
2015-07-27virtio: get_features() can failJason Wang
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>
2015-07-27virtio: set any_layout in virtio coreMichael S. Tsirkin
Exceptions: - virtio-blk - compat machine types Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-07-27virtio: hide legacy features from modern guestsMichael S. Tsirkin
NOTIFY_ON_EMPTY, ANY_LAYOUT and BAD are only valid on the legacy interface. Hide them from modern guests. Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-06-10virtio: add modern config accessorsMichael S. Tsirkin
virtio 1.0 defines config space as LE, as opposed to pre-1.0 which was native endian. Add API for transports to execute word/dword accesses in little endian format - will be useful for mmio and pci (byte access is also wrapped, for completeness). For simplicity, we still keep config in host native endian format, byteswap to LE on guest access. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
2015-06-10virtio: generation counter supportMichael S. Tsirkin
Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
2015-06-10virtio: allow to fail setting statusCornelia Huck
virtio-1 allow setting of the FEATURES_OK status bit to fail if the negotiated feature bits are inconsistent: let's fail virtio_set_status() in that case and update virtio-ccw to post an error to the guest. 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> Reviewed-by: Michael S. Tsirkin <mst@redhat.com>