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2017-06-02virtio: add virtqueue_alloc_element tracepointPaolo Bonzini1-0/+1
This tracepoint can help diagnosing failures due to memory fragmentation in the guest. 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>
2017-05-18migration: migration.h was not neededJuan Quintela1-1/+0
This files don't use any function from migration.h, so drop it. Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Reviewed-by: Peter Xu <peterx@redhat.com>
2017-05-18virtio: allow broken device to notify guestGreg Kurz1-2/+2
According to section 2.1.2 of the virtio-1 specification: "The device SHOULD set DEVICE_NEEDS_RESET when it enters an error state that a reset is needed. If DRIVER_OK is set, after it sets DEVICE_NEEDS_RESET, the device MUST send a device configuration change notification to the driver." Commit "f5ed36635d8f virtio: stop virtqueue processing if device is broken" introduced a virtio_error() call that just does that: - internally mark the device as broken - set the DEVICE_NEEDS_RESET bit in the status - send a configuration change notification Unfortunately, virtio_notify_vector(), called by virtio_notify_config(), returns right away when the device is marked as broken and the notification isn't sent in this case. The spec doesn't say whether a broken device can send notifications in other situations or not. But since the driver isn't supposed to do anything but to reset the device, it makes sense to keep the check in virtio_notify_config(). Marking the device as broken AFTER the configuration change notification was sent is enough to fix the issue. 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> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-03-22virtio: always use handle_aio_output if registeredPaolo Bonzini1-1/+12
Commit ad07cd6 ("virtio-scsi: always use dataplane path if ioeventfd is active", 2016-10-30) and 9ffe337 ("virtio-blk: always use dataplane path if ioeventfd is active", 2016-10-30) broke the virtio 1.0 indirect access registers. The indirect access registers bypass the ioeventfd, so that virtio-blk and virtio-scsi now repeatedly try to initialize dataplane instead of triggering the guest->host EventNotifier. Detect the situation by checking vq->handle_aio_output; if it is not NULL, trigger the EventNotifier, which is how the device expects to get notifications and in fact the only thread-safe manner to deliver them. Fixes: ad07cd6 Fixes: 9ffe337 Cc: qemu-stable@nongnu.org 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>
2017-03-15virtio: validate address space cache during initJason Wang1-6/+27
We don't check the return value of address_space_cache_init(), this may lead buggy driver use incorrect region caches. Instead of triggering an assert, catch and warn this early in virtio_init_region_cache(). Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.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>
2017-03-15virtio: destroy region cache during resetJason Wang1-15/+30
We don't destroy region cache during reset which can make the maps of previous driver leaked to a buggy or malicious driver that don't set vring address before starting to use the device. Fix this by destroy the region cache during reset and validate it before trying to see them. Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.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>
2017-03-15virtio: guard against NULL pfnJason Wang1-0/+26
To avoid access stale memory region cache after reset, this patch check the existence of virtqueue pfn for all exported virtqueue access helpers before trying to use them. Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.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>
2017-03-02virtio: add missing region cache init in virtio_load()Stefan Hajnoczi1-6/+19
Commit 97cd965c070152bc626c7507df9fb356bbe1cd81 ("virtio: use VRingMemoryRegionCaches for avail and used rings") switched to a memory region cache to avoid repeated map/unmap operations. The virtio_load() process is a little tricky because vring addresses are serialized in two separate places. VIRTIO 1.0 devices serialize desc and then a subsection with used and avail. Legacy devices only serialize desc. Live migration of VIRTIO 1.0 devices fails on the destination host with: VQ 0 size 0x80 < last_avail_idx 0x12f8 - used_idx 0x0 Failed to load virtio-blk:virtio error while loading state for instance 0x0 of device '0000:00:04.0/virtio-blk' This happens because the memory region cache is only initialized after desc is loaded and not after the used and avail subsection is loaded. If the guest chose memory addresses that don't match the legacy ring layout then the wrong guest memory location is accessed. Wait until all ring addresses are known before trying to initialize the region cache. Also clarify the incomplete comment about VIRTIO-1 ring address subsection. Cc: Dr. David Alan Gilbert <dgilbert@redhat.com> Cc: Paolo Bonzini <pbonzini@redhat.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> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com> Tested-by: Eric Auger <eric.auger@redhat.com>
2017-03-02virtio: invalidate memory in vring_set_avail_event()Stefan Hajnoczi1-0/+1
Remember to invalidate the avail event field so the memory pages are marked dirty. Cc: Paolo Bonzini <pbonzini@redhat.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: Eric Auger <eric.auger@redhat.com>
2017-03-02virtio: guard vring access when setting notificationCornelia Huck1-0/+4
Switching to vring caches exposed an existing bug in virtio_queue_set_notification(): We can't access vring structures if they have not been set up yet. This may happen, for example, for virtio-blk devices with multiple queues: The code will try to switch notifiers for every queue, but the guest may have only set up a subset of them. Fix this by guarding access to the vring memory by checking for vring.desc. The first aio poll will iron out any remaining inconsistencies for later-configured queues (buggy legacy drivers). 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>
2017-03-02virtio: check for vring setup in virtio_queue_emptyPaolo Bonzini1-1/+1
If the vring has not been set up, there is nothing in the virtqueue. virtio_queue_host_notifier_aio_poll calls virtio_queue_empty even in this case; we have to filter it out just like virtio_queue_notify_aio_vq. Reported-by: Gerd Hoffmann <kraxel@redhat.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> Tested-by: Laszlo Ersek <lersek@redhat.com> Tested-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2017-02-17virtio: Fix no interrupt when not creating msi controllerMichael S. Tsirkin1-3/+8
For ARM virt machine, if we use virt-2.7 which will not create ITS node, the virtio-net can not recieve interrupts so it can't get ip address through dhcp. This fixes commit 83d768b(virtio: set ISR on dataplane notifications). 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>
2017-02-17virtio: use VRingMemoryRegionCaches for avail and used ringsPaolo Bonzini1-36/+96
The virtio-net change is necessary because it uses virtqueue_fill and virtqueue_flush instead of the more convenient virtqueue_push. 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: check for vring setup in virtio_queue_update_used_idxPaolo Bonzini1-1/+3
If the vring has not been set up, it is not necessary for vring_used_idx to do anything (as is already the case when the caller is virtio_load). This is harmless for now, but it will be a problem when the MemoryRegionCache has not been set up. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-02-17virtio: use VRingMemoryRegionCaches for descriptor ringPaolo Bonzini1-14/+12
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: add MemoryListener to cache ring translationsPaolo Bonzini1-3/+102
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: use MemoryRegionCache to access descriptorsPaolo Bonzini1-41/+39
For now, the cache is created on every virtqueue_pop. Later on, direct descriptors will be able to reuse it. 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: use address_space_map/unmap to access descriptorsPaolo Bonzini1-28/+75
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 Zheng1-6/+9
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 Bonzini1-1/+1
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 Duan1-4/+11
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 Maydell1-5/+5
* 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 Maydell1-0/+5
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. Tsirkin1-0/+5
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. Tsirkin1-20/+13
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 Hajnoczi1-0/+3
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 Hajnoczi1-12/+6
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 Bonzini1-5/+5
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 Benditovich1-0/+38
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 Benditovich1-0/+5
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 Pasic1-3/+5
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 Wang1-20/+37
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 Hajnoczi1-0/+18
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 Hajnoczi1-6/+12
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 Hajnoczi1-1/+15
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 Hajnoczi1-2/+2
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 Bonzini1-8/+28
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 Bonzini1-5/+17
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 Bonzini1-0/+16
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 Kurz1-11/+0
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. Tsirkin1-0/+2
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 Prosek1-1/+1
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 Prosek1-4/+4
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 Bonzini1-18/+9
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 Bonzini1-5/+3
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 Bonzini1-3/+13
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 Bonzini1-34/+4
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 Bonzini1-0/+8
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 Bonzini1-0/+64
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 Gilbert1-0/+14
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>