From a0be1db4304f51c99af6b6e515549794182a94df Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Wed, 14 Sep 2016 17:33:26 +0100 Subject: virtio_pci: Limit DMA mask to 44 bits for legacy virtio devices 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 --- drivers/virtio/virtio_pci_legacy.c | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-) (limited to 'drivers/virtio') diff --git a/drivers/virtio/virtio_pci_legacy.c b/drivers/virtio/virtio_pci_legacy.c index 8c4e61783441..6d9e5173d5fa 100644 --- a/drivers/virtio/virtio_pci_legacy.c +++ b/drivers/virtio/virtio_pci_legacy.c @@ -212,10 +212,18 @@ int virtio_pci_legacy_probe(struct virtio_pci_device *vp_dev) return -ENODEV; } - rc = dma_set_mask_and_coherent(&pci_dev->dev, DMA_BIT_MASK(64)); - if (rc) - rc = dma_set_mask_and_coherent(&pci_dev->dev, - DMA_BIT_MASK(32)); + rc = dma_set_mask(&pci_dev->dev, DMA_BIT_MASK(64)); + if (rc) { + rc = dma_set_mask_and_coherent(&pci_dev->dev, DMA_BIT_MASK(32)); + } else { + /* + * The virtio ring base address is expressed as a 32-bit PFN, + * with a page size of 1 << VIRTIO_PCI_QUEUE_ADDR_SHIFT. + */ + dma_set_coherent_mask(&pci_dev->dev, + DMA_BIT_MASK(32 + VIRTIO_PCI_QUEUE_ADDR_SHIFT)); + } + if (rc) dev_warn(&pci_dev->dev, "Failed to enable 64-bit or 32-bit DMA. Trying to continue, but this might not work.\n"); -- cgit v1.2.3 From 0ea1e4a6d9b62cf29e210d2b4ba9fd43917522e3 Mon Sep 17 00:00:00 2001 From: Ladi Prosek Date: Wed, 31 Aug 2016 14:00:04 +0200 Subject: virtio_ring: Make interrupt suppression spec compliant 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 --- drivers/virtio/virtio_ring.c | 14 +++++++++----- 1 file changed, 9 insertions(+), 5 deletions(-) (limited to 'drivers/virtio') diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c index ed9c9eeedfe5..6b2cd922d322 100644 --- a/drivers/virtio/virtio_ring.c +++ b/drivers/virtio/virtio_ring.c @@ -732,7 +732,8 @@ void virtqueue_disable_cb(struct virtqueue *_vq) if (!(vq->avail_flags_shadow & VRING_AVAIL_F_NO_INTERRUPT)) { vq->avail_flags_shadow |= VRING_AVAIL_F_NO_INTERRUPT; - vq->vring.avail->flags = cpu_to_virtio16(_vq->vdev, vq->avail_flags_shadow); + if (!vq->event) + vq->vring.avail->flags = cpu_to_virtio16(_vq->vdev, vq->avail_flags_shadow); } } @@ -764,7 +765,8 @@ unsigned virtqueue_enable_cb_prepare(struct virtqueue *_vq) * entry. Always do both to keep code simple. */ if (vq->avail_flags_shadow & VRING_AVAIL_F_NO_INTERRUPT) { vq->avail_flags_shadow &= ~VRING_AVAIL_F_NO_INTERRUPT; - vq->vring.avail->flags = cpu_to_virtio16(_vq->vdev, vq->avail_flags_shadow); + if (!vq->event) + vq->vring.avail->flags = cpu_to_virtio16(_vq->vdev, vq->avail_flags_shadow); } vring_used_event(&vq->vring) = cpu_to_virtio16(_vq->vdev, last_used_idx = vq->last_used_idx); END_USE(vq); @@ -832,10 +834,11 @@ bool virtqueue_enable_cb_delayed(struct virtqueue *_vq) * more to do. */ /* Depending on the VIRTIO_RING_F_USED_EVENT_IDX feature, we need to * either clear the flags bit or point the event index at the next - * entry. Always do both to keep code simple. */ + * entry. Always update the event index to keep code simple. */ if (vq->avail_flags_shadow & VRING_AVAIL_F_NO_INTERRUPT) { vq->avail_flags_shadow &= ~VRING_AVAIL_F_NO_INTERRUPT; - vq->vring.avail->flags = cpu_to_virtio16(_vq->vdev, vq->avail_flags_shadow); + if (!vq->event) + vq->vring.avail->flags = cpu_to_virtio16(_vq->vdev, vq->avail_flags_shadow); } /* TODO: tune this threshold */ bufs = (u16)(vq->avail_idx_shadow - vq->last_used_idx) * 3 / 4; @@ -953,7 +956,8 @@ struct virtqueue *__vring_new_virtqueue(unsigned int index, /* No callback? Tell other side not to bother us. */ if (!callback) { vq->avail_flags_shadow |= VRING_AVAIL_F_NO_INTERRUPT; - vq->vring.avail->flags = cpu_to_virtio16(vdev, vq->avail_flags_shadow); + if (!vq->event) + vq->vring.avail->flags = cpu_to_virtio16(vdev, vq->avail_flags_shadow); } /* Put everything in free lists. */ -- cgit v1.2.3 From 8424af5336b34043a705d66bdf2c1428048ef085 Mon Sep 17 00:00:00 2001 From: Konstantin Neumoin Date: Thu, 29 Sep 2016 13:17:12 +0300 Subject: virtio: update balloon size in balloon "probe" 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 --- drivers/virtio/virtio_balloon.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'drivers/virtio') diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c index 4e7003db12c4..181793f07852 100644 --- a/drivers/virtio/virtio_balloon.c +++ b/drivers/virtio/virtio_balloon.c @@ -577,6 +577,8 @@ static int virtballoon_probe(struct virtio_device *vdev) virtio_device_ready(vdev); + if (towards_target(vb)) + virtballoon_changed(vdev); return 0; out_del_vqs: -- cgit v1.2.3 From 3dae2c6152fbbc6224343551158b61aad585cedf Mon Sep 17 00:00:00 2001 From: Juergen Gross Date: Tue, 11 Oct 2016 11:02:14 +0200 Subject: virtio: remove config.c Remove unused file config.c Signed-off-by: Juergen Gross Signed-off-by: Michael S. Tsirkin --- drivers/virtio/config.c | 12 ------------ 1 file changed, 12 deletions(-) delete mode 100644 drivers/virtio/config.c (limited to 'drivers/virtio') diff --git a/drivers/virtio/config.c b/drivers/virtio/config.c deleted file mode 100644 index f70bcd2ff98f..000000000000 --- a/drivers/virtio/config.c +++ /dev/null @@ -1,12 +0,0 @@ -/* Configuration space parsing helpers for virtio. - * - * The configuration is [type][len][... len bytes ...] fields. - * - * Copyright 2007 Rusty Russell, IBM Corporation. - * GPL v2 or later. - */ -#include -#include -#include -#include - -- cgit v1.2.3 From 75bfa81bf0897ba87f1e1b9b576a07536029b86a Mon Sep 17 00:00:00 2001 From: "Michael S. Tsirkin" Date: Mon, 31 Oct 2016 00:38:21 +0200 Subject: virtio_ring: mark vring_dma_dev inline 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 --- drivers/virtio/virtio_ring.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/virtio') diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c index 6b2cd922d322..489bfc61cf30 100644 --- a/drivers/virtio/virtio_ring.c +++ b/drivers/virtio/virtio_ring.c @@ -167,7 +167,7 @@ static bool vring_use_dma_api(struct virtio_device *vdev) * making all of the arch DMA ops work on the vring device itself * is a mess. For now, we use the parent device for DMA ops. */ -static struct device *vring_dma_dev(const struct vring_virtqueue *vq) +static inline struct device *vring_dma_dev(const struct vring_virtqueue *vq) { return vq->vq.vdev->dev.parent; } -- cgit v1.2.3