linux/drivers/virtio, branch v4.9

virtio_ring: mark vring_dma_dev inline

2016-10-30T22:40:08Z

This inline function is unused on configurations where dma_map/unmap are empty macros. Make the function inline to avoid gcc errors because of an unused static function. Signed-off-by: Michael S. Tsirkin

virtio: remove config.c

2016-10-30T22:21:45Z

Remove unused file config.c Signed-off-by: Juergen Gross Signed-off-by: Michael S. Tsirkin

virtio: update balloon size in balloon "probe"

2016-10-30T22:21:41Z

The following commit 'fad7b7b27b6a (virtio_balloon: Use a workqueue instead of "vballoon" kthread)' has added a regression. Original code with kthread starts the thread inside probe and checks the necessity to update balloon inside the thread immediately. Nowadays the code behaves differently. Work is queued only on the first command from the host after the negotiation. Thus there is a window especially at the guest startup or the module reloading when the balloon size is not updated until the notification from the host. This patch adds balloon size check at the end of the probe to match original behaviour. Signed-off-by: Konstantin Neumoin Signed-off-by: Denis V. Lunev Signed-off-by: Michael S. Tsirkin

virtio_ring: Make interrupt suppression spec compliant

2016-10-30T22:21:40Z

According to the spec, if the VIRTIO_RING_F_EVENT_IDX feature bit is negotiated the driver MUST set flags to 0. Not dirtying the available ring in virtqueue_disable_cb also has a minor positive performance impact, improving L1 dcache load missed by ~0.5% in vring_bench. Writes to the used event field (vring_used_event) are still unconditional. Cc: Michael S. Tsirkin Cc: # f277ec4 virtio_ring: shadow available Cc: Signed-off-by: Ladi Prosek Signed-off-by: Michael S. Tsirkin

virtio_pci: Limit DMA mask to 44 bits for legacy virtio devices

2016-10-30T22:21:39Z

Legacy virtio defines the virtqueue base using a 32-bit PFN field, with a read-only register indicating a fixed page size of 4k. This can cause problems for DMA allocators that allocate top down from the DMA mask, which is set to 64 bits. In this case, the addresses are silently truncated to 44-bit, leading to IOMMU faults, failure to read from the queue or data corruption. This patch restricts the coherent DMA mask for legacy PCI virtio devices to 44 bits, which matches the specification. Cc: stable@vger.kernel.org Cc: Andy Lutomirski Cc: Michael S. Tsirkin Cc: Benjamin Serebrin Signed-off-by: Will Deacon Signed-off-by: Michael S. Tsirkin

virtio: mark vring_dma_dev() static

2016-09-09T18:12:35Z

We get 1 warning when building kernel with W=1: drivers/virtio/virtio_ring.c:170:16: warning: no previous prototype for 'vring_dma_dev' [-Wmissing-prototypes] In fact, this function is only used in the file in which it is declared and don't need a declaration, but can be made static. so this patch marks this function with 'static'. Signed-off-by: Baoyou Xie Acked-by: Arnd Bergmann Signed-off-by: Michael S. Tsirkin

virtio: fix error handling for debug builds

2016-08-09T10:42:35Z

On error, virtqueue_add calls START_USE but not END_USE. Thankfully that's normally empty anyway, but might not be when debugging. Fix it up. Signed-off-by: Michael S. Tsirkin

virtio: fix memory leak in virtqueue_add()

2016-08-09T10:42:34Z

When using the indirect buffers feature, 'desc' is allocated in virtqueue_add() but isn't freed before leaving on a ring full error, causing a memory leak. For example, it seems rather clear that this can trigger with virtio net if mergeable buffers are not used. Cc: stable@vger.kernel.org Signed-off-by: Wei Yongjun Signed-off-by: Michael S. Tsirkin

Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

2016-08-06T13:20:13Z

Pull virtio/vhost updates from Michael Tsirkin: - new vsock device support in host and guest - platform IOMMU support in host and guest, including compatibility quirks for legacy systems. - misc fixes and cleanups. * tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: VSOCK: Use kvfree() vhost: split out vringh Kconfig vhost: detect 32 bit integer wrap around vhost: new device IOTLB API vhost: drop vringh dependency vhost: convert pre sorted vhost memory array to interval tree vhost: introduce vhost memory accessors VSOCK: Add Makefile and Kconfig VSOCK: Introduce vhost_vsock.ko VSOCK: Introduce virtio_transport.ko VSOCK: Introduce virtio_vsock_common.ko VSOCK: defer sock removal to transports VSOCK: transport-specific vsock_transport functions vhost: drop vringh dependency vop: pull in vhost Kconfig virtio: new feature to detect IOMMU device quirk balloon: check the number of available pages in leak balloon vhost: lockless enqueuing vhost: simplify work flushing

virtio: new feature to detect IOMMU device quirk

2016-08-01T18:44:52Z

The interaction between virtio and IOMMUs is messy. On most systems with virtio, physical addresses match bus addresses, and it doesn't particularly matter which one we use to program the device. On some systems, including Xen and any system with a physical device that speaks virtio behind a physical IOMMU, we must program the IOMMU for virtio DMA to work at all. On other systems, including SPARC and PPC64, virtio-pci devices are enumerated as though they are behind an IOMMU, but the virtio host ignores the IOMMU, so we must either pretend that the IOMMU isn't there or somehow map everything as the identity. Add a feature bit to detect that quirk: VIRTIO_F_IOMMU_PLATFORM. Any device with this feature bit set to 0 needs a quirk and has to be passed physical addresses (as opposed to bus addresses) even though the device is behind an IOMMU. Note: it has to be a per-device quirk because for example, there could be a mix of passed-through and virtual virtio devices. As another example, some devices could be implemented by an out of process hypervisor backend (in case of qemu vhost, or vhost-user) and so support for an IOMMU needs to be coded up separately. It would be cleanest to handle this in IOMMU core code, but that needs per-device DMA ops. While we are waiting for that to be implemented, use a work-around in virtio core. Note: a "noiommu" feature is a quirk - add a wrapper to make that clear. Signed-off-by: Michael S. Tsirkin