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2017-02-17virtio: use address_space_map/unmap to access descriptorsPaolo Bonzini
This makes little difference, but it makes the code change smaller for the next patch that introduces MemoryRegionCache. This is because map/unmap are similar to MemoryRegionCache init/destroy. 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>
2017-01-24migration: extend VMStateInfoJianjun Duan
Current migration code cannot handle some data structures such as QTAILQ in qemu/queue.h. Here we extend the signatures of put/get in VMStateInfo so that customized handling is supported. put now will return int type. Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Jianjun Duan <duanj@linux.vnet.ibm.com> Message-Id: <1484852453-12728-2-git-send-email-duanj@linux.vnet.ibm.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2017-01-20Merge remote-tracking branch 'remotes/bonzini/tags/for-upstream' into stagingPeter Maydell
* QOM interface fix (Eduardo) * RTC fixes (Gaohuai, Igor) * Memory leak fixes (Li Qiang, me) * Ctrl-a b regression (Marc-André) * Stubs cleanups and fixes (Leif, me) * hxtool tweak (me) * HAX support (Vincent) * QemuThread, exec.c and SCSI fixes (Roman, Xinhua, me) * PC_COMPAT_2_8 fix (Marcelo) * stronger bitmap assertions (Peter) # gpg: Signature made Fri 20 Jan 2017 12:49:01 GMT # gpg: using RSA key 0xBFFBD25F78C7AE83 # gpg: Good signature from "Paolo Bonzini <bonzini@gnu.org>" # gpg: aka "Paolo Bonzini <pbonzini@redhat.com>" # Primary key fingerprint: 46F5 9FBD 57D6 12E7 BFD4 E2F7 7E15 100C CD36 69B1 # Subkey fingerprint: F133 3857 4B66 2389 866C 7682 BFFB D25F 78C7 AE83 * remotes/bonzini/tags/for-upstream: (35 commits) pc.h: move x-mach-use-reliable-get-clock compat entry to PC_COMPAT_2_8 bitmap: assert that start and nr are non negative Revert "win32: don't run subprocess tests on Mingw32 platform" hax: add Darwin support Plumb the HAXM-based hardware acceleration support target/i386: Add Intel HAX files kvm: move cpu synchronization code KVM: PPC: eliminate unnecessary duplicate constants ramblock-notifier: new char: fix ctrl-a b not working exec: Add missing rcu_read_unlock x86: ioapic: fix fail migration when irqchip=split x86: ioapic: dump version for "info ioapic" x86: ioapic: add traces for ioapic hxtool: emit Texinfo headings as @subsection qemu-thread: fix qemu_thread_set_name() race in qemu_thread_create() serial: fix memory leak in serial exit scsi-block: fix direction of BYTCHK test for VERIFY commands pc: fix crash in rtc_set_memory() if initial cpu is marked as hotplugged acpi: filter based on CONFIG_ACPI_X86 rather than TARGET ... # Conflicts: # include/hw/i386/pc.h
2017-01-20Merge remote-tracking branch 'remotes/cohuck/tags/s390x-20170120-v2' into ↵Peter Maydell
staging First set of s390x patches for 2.9: - rework of the zpci code, giving us proper multibus support - introduction of the 2.9 machine - fixes and improvements # gpg: Signature made Fri 20 Jan 2017 09:11:58 GMT # gpg: using RSA key 0xDECF6B93C6F02FAF # gpg: Good signature from "Cornelia Huck <huckc@linux.vnet.ibm.com>" # gpg: aka "Cornelia Huck <cornelia.huck@de.ibm.com>" # Primary key fingerprint: C3D0 D66D C362 4FF6 A8C0 18CE DECF 6B93 C6F0 2FAF * remotes/cohuck/tags/s390x-20170120-v2: virtio-ccw: fix ring sizing s390x/pci: merge msix init functions s390x/pci: handle PCIBridge bus number s390x/pci: use hashtable to look up zpci via fh s390x/pci: PCI multibus bridge handling s390x/pci: optimize calling s390_get_phb() s390x/pci: change the device array to a list s390x/pci: dynamically allocate iommu s390x/pci: make S390PCIIOMMU inherit Object s390x/kvm: use kvm_gsi_routing_enabled in flic s390x: add compat machine for 2.9 s390x: remove double compat statement Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
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>
2017-01-19virtio: fix up max size checksMichael S. Tsirkin
Coverity reports that ARRAY_SIZE(elem->out_sg) (and all the others too) is wrong because elem->out_sg is a pointer. However, the check is not in the right place and the max_size argument of virtqueue_map_iovec can be removed. The check on in_num/out_num should be moved to qemu_get_virtqueue_element instead, before the call to virtqueue_alloc_element. Cc: qemu-stable@nongnu.org Reported-by: Paolo Bonzini <pbonzini@redhat.com> Fixes: 3724650db07057333879484c8bc7d900b5c1bf8e ("virtio: introduce virtqueue_alloc_element") Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2017-01-18virtio: disable notifications again after poll succeededStefan Hajnoczi
While AioContext is in polling mode virtqueue notifications are not necessary. Some device virtqueue handlers enable notifications. Make sure they stay disabled to avoid unnecessary vmexits. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Tested-by: Richard Henderson <rth@twiddle.net> Tested-by: Laszlo Ersek <lersek@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-01-18Revert "virtio: turn vq->notification into a nested counter"Stefan Hajnoczi
This reverts commit aff8fd18f1786fc5af259a9bc0077727222f51ca. Both virtio-net and virtio-crypto do not balance virtio_queue_set_notification() enable and disable calls. This makes the notifications_disabled counter unreliable and Doug Goldstein reported the following assertion failure: #3 0x00007ffff44d1c62 in __GI___assert_fail ( assertion=assertion@entry=0x555555ae8e8a "vq->notification_disabled > 0", file=file@entry=0x555555ae89c0 "/home/doug/work/qemu/hw/virtio/virtio.c", line=line@entry=215, function=function@entry=0x555555ae9630 <__PRETTY_FUNCTION__.43707> "virtio_queue_set_notification") at assert.c:101 #4 0x00005555557f25d6 in virtio_queue_set_notification (vq=0x55555666aa90, enable=enable@entry=1) at /home/doug/work/qemu/hw/virtio/virtio.c:215 #5 0x00005555557dc311 in virtio_net_has_buffers (q=<optimized out>, q=<optimized out>, bufsize=102) at /home/doug/work/qemu/hw/net/virtio-net.c:1008 #6 virtio_net_receive (nc=<optimized out>, buf=0x555557386b88 "", size=102) at /home/doug/work/qemu/hw/net/virtio-net.c:1148 #7 0x00005555559cad33 in nc_sendv_compat (flags=<optimized out>, iovcnt=1, iov=0x7fffead746d0, nc=0x55555788b340) at net/net.c:705 #8 qemu_deliver_packet_iov (sender=<optimized out>, flags=<optimized out>, iov=0x7fffead746d0, iovcnt=1, opaque=0x55555788b340) at net/net.c:732 #9 0x00005555559cd929 in qemu_net_queue_deliver (size=<optimized out>, data=<optimized out>, flags=<optimized out>, sender=<optimized out>, queue=0x55555788b550) at net/queue.c:164 #10 qemu_net_queue_flush (queue=0x55555788b550) at net/queue.c:261 This patch is safe to revert since it's just an optimization for virtqueue polling. The next patch will improve the situation again without resorting to nesting. Reported-by: Doug Goldstein <cardoe@cardoe.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Tested-by: Richard Henderson <rth@twiddle.net> Tested-by: Laszlo Ersek <lersek@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-01-16event_notifier: cleanups around event_notifier_set_handlerPaolo Bonzini
Remove the useless is_external argument. Since the iohandler AioContext is never used for block devices, aio_disable_external is never called on it. This lets us remove stubs/iohandler.c. Signed-off-by: Paolo Bonzini <pbonzini@redhat.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: fix vq->inuse recalc after migrHalil Pasic
Correct recalculation of vq->inuse after migration for the corner case where the avail_idx has already wrapped but used_idx not yet. Also change the type of the VirtQueue.inuse to unsigned int. This is done to be consistent with other members representing sizes (VRing.num), and because C99 guarantees max ring size < UINT_MAX but does not guarantee max ring size < INT_MAX. Signed-off-by: Halil Pasic <pasic@linux.vnet.ibm.com> Fixes: bccdef6b ("virtio: recalculate vq->inuse after migration") CC: qemu-stable@nongnu.org Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-01-10virtio: 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>
2017-01-03virtio: disable virtqueue notifications during pollingStefan Hajnoczi
This is a performance optimization to eliminate vmexits during polling. It also avoids spurious ioeventfd processing after polling ends. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Message-id: 20161201192652.9509-12-stefanha@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-01-03virtio: turn vq->notification into a nested counterStefan Hajnoczi
Polling should disable virtqueue notifications but that requires nested virtio_queue_set_notification() calls. Turn vq->notification into a counter so it is possible to do nesting. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Message-id: 20161201192652.9509-10-stefanha@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-01-03virtio: poll virtqueues for new buffersStefan Hajnoczi
Add an AioContext poll handler to detect new virtqueue buffers without waiting for a guest->host notification. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Message-id: 20161201192652.9509-5-stefanha@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-01-03aio: add AioPollFn and io_poll() interfaceStefan Hajnoczi
The new AioPollFn io_poll() argument to aio_set_fd_handler() and aio_set_event_handler() is used in the next patch. Keep this code change separate due to the number of files it touches. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Message-id: 20161201192652.9509-3-stefanha@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@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: access ISR atomicallyPaolo Bonzini
This will be needed once dataplane will be able to set it outside the big QEMU lock. 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>
2016-10-30virtio: use virtio_bus_set_host_notifier to start/stop ioeventfdPaolo Bonzini
ioeventfd_disabled was the only reason for the default implementation of virtio_device_start_ioeventfd not to use virtio_bus_set_host_notifier. This is now fixed, and the sole entry point to set up ioeventfd can 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: remove set_handler argument from set_host_notifier_internalPaolo Bonzini
Make virtio_device_start_ioeventfd_impl use the same logic as dataplane to set up the host notifier. This removes the need for the set_handler argument in set_host_notifier_internal. This is a first step towards using virtio_bus_set_host_notifier as the sole entry point to set up ioeventfds. At least now the functions have the same interface, but they still differ in that virtio_bus_set_host_notifier sets ioeventfd_disabled. 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>
2016-10-30Revert "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: handle virtqueue_get_head() errorsStefan Hajnoczi
Stop processing the vring if virtqueue_get_head() fetches an out-of-bounds head index. 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>
2016-09-23virtio: handle virtqueue_num_heads() errorsStefan Hajnoczi
If the avail ring index is bogus virtqueue_num_heads() must return -EINVAL. The only caller is virtqueue_get_avail_bytes(). Return saying no bytes are available when virtqueue_num_heads() fails. 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>
2016-09-23virtio: handle virtqueue_read_next_desc() errorsStefan Hajnoczi
Stop processing the vring if an avail ring index is invalid. 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>
2016-09-23virtio: use unsigned int for virtqueue_get_avail_bytes() indexStefan Hajnoczi
The virtio code uses int, unsigned int, and uint16_t for virtqueue indices. The uint16_t is used for the low-level descriptor layout in virtio_ring.h while code that isn't concerned with descriptor layout can use unsigned int. Use of int is problematic because it can result in signed/unsigned comparison and incompatible int*/unsigned int* pointer types. Make the virtqueue_get_avail_bytes() 'i' variable unsigned int. This eliminates the need to introduce casts and modify code further in the patches that follow. 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>
2016-09-23virtio: handle virtqueue_get_avail_bytes() errorsStefan Hajnoczi
If the vring is invalid, tell the caller no bytes are available and mark the device broken. 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>
2016-09-23virtio: handle virtqueue_map_desc() errorsStefan Hajnoczi
Errors can occur during virtqueue_pop(), especially in virtqueue_map_desc(). In order to handle this we must unmap iov[] before returning NULL. The caller will consider the virtqueue empty and the virtio_error() call will have marked the device broken. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-09-23virtio: migrate vdev->broken flagStefan Hajnoczi
Send a subsection if the vdev->broken flag is set. This allows live migration of broken virtio devices. The subsection is only sent if vdev->broken has been set. In most cases the flag will be clear and no subsection will be sent. 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>
2016-09-23virtio: 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>
2016-09-23virtio: fix stray tab characterStefan Hajnoczi
Fix a single occurrence of a tab character in a file that otherwise uses spaces for indentation. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Fam Zheng <famz@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> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2016-09-23virtio: add check for descriptor's mapped addressPrasad J Pandit
virtio back end uses set of buffers to facilitate I/O operations. If its size is too large, 'cpu_physical_memory_map' could return a null address. This would result in a null dereference while un-mapping descriptors. Add check to avoid it. Reported-by: Qinghao Tang <luodalongde@gmail.com> Signed-off-by: Prasad J Pandit <pjp@fedoraproject.org> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Laszlo Ersek <lersek@redhat.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>
2016-09-09virtio: zero vq->inuse in virtio_reset()Stefan Hajnoczi
vq->inuse must be zeroed upon device reset like most other virtqueue fields. In theory, virtio_reset() just needs assert(vq->inuse == 0) since devices must clean up in-flight requests during reset (requests cannot not be leaked!). In practice, it is difficult to achieve vq->inuse == 0 across reset because balloon, blk, 9p, etc implement various different strategies for cleaning up requests. Most devices call g_free(elem) directly without telling virtio.c that the VirtQueueElement is cleaned up. Therefore vq->inuse is not decremented during reset. This patch zeroes vq->inuse and trusts that devices are not leaking VirtQueueElements across reset. I will send a follow-up series that refactors request life-cycle across all devices and converts vq->inuse = 0 into assert(vq->inuse == 0) but this more invasive approach is not appropriate for stable trees. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Cc: qemu-stable <qemu-stable@nongnu.org> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Ladi Prosek <lprosek@redhat.com>
2016-08-23virtio: decrement vq->inuse in virtqueue_discard()Stefan Hajnoczi
virtqueue_discard() moves vq->last_avail_idx back so the element can be popped again. It's necessary to decrement vq->inuse to avoid "leaking" the element count. Cc: qemu-stable@nongnu.org Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@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>
2016-08-23virtio: recalculate vq->inuse after migrationStefan Hajnoczi
The vq->inuse field is not migrated. Many devices don't hold VirtQueueElements across migration so it doesn't matter that vq->inuse starts at 0 on the destination QEMU. At least virtio-serial, virtio-blk, and virtio-balloon migrate while holding VirtQueueElements. For these devices we need to recalculate vq->inuse upon load so the value is correct. Cc: qemu-stable@nongnu.org Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@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>