linux/drivers/virtio, branch v3.7

virtio: Don't access index after unregister.

2012-11-09T04:24:24Z

Virtio wants to release used indices after the corresponding virtio device has been unregistered. However, virtio does not hold an extra reference, giving up its last reference with device_unregister(), making accessing dev->index afterwards invalid. I actually saw problems when testing my (not-yet-merged) virtio-ccw code: - device_add virtio-net,id=xxx -> creates device virtio with n>0 - device_del xxx -> deletes virtio, but calls ida_simple_remove with an index of 0 - device_add virtio-net,id=xxx -> tries to add virtio0, which is still in use... So let's save the index we want to release before calling device_unregister(). Signed-off-by: Cornelia Huck Acked-by: Sjur Brændeland Cc: stable@kernel.org Signed-off-by: Rusty Russell

virtio_mmio: Don't attempt to create empty virtqueues

2012-09-28T05:35:16Z

If a virtio device reports a QueueNumMax of 0, vring_new_virtqueue() doesn't check this, and thanks to an unsigned (i < num - 1) loop guard, scribbles over memory when initialising the free list. Avoid by not trying to create zero-descriptor queues, as there's no way to do any I/O with one. Signed-off-by: Brian Foley Signed-off-by: Pawel Moll Signed-off-by: Rusty Russell

virtio_mmio: fix off by one error allocating queue

2012-09-28T05:35:16Z

vm_setup_vq fails to allow VirtQueues needing only 2 pages of storage, as it should. Found with a kernel using 64kB pages, but can be provoked if a virtio device reports QueueNumMax where the descriptor table and available ring fit in one page, and the used ring on the second (<= 227 descriptors with 4kB pages and <= 3640 with 64kB pages.) Signed-off-by: Brian Foley Signed-off-by: Pawel Moll Signed-off-by: Rusty Russell

drivers/virtio/virtio_pci.c: fix error return code

2012-09-28T05:35:16Z

Convert a nonnegative error return code to a negative one, as returned elsewhere in the function. A simplified version of the semantic match that finds this problem is as follows: (http://coccinelle.lip6.fr/) // ( if@p1 (\(ret < 0\|ret != 0\)) { ... return ret; } | ret@p1 = 0 ) ... when != ret = e1 when != &ret *if(...) { ... when != ret = e2 when forall return ret; } // Signed-off-by: Peter Senna Tschudin Signed-off-by: Rusty Russell

virtio: don't crash when device is buggy

2012-09-28T05:35:16Z

Because of a sanity check in virtio_dev_remove, a buggy device can crash kernel. And in case of rproc it's userspace so it's not a good idea. We are unloading a driver so how bad can it be? Be less aggressive in handling this error: if it's a driver bug, warning once should be enough. Signed-off-by: Michael S. Tsirkin Signed-off-by: Rusty Russell

virtio: remove CONFIG_VIRTIO_RING

2012-09-28T05:35:15Z

Everyone who selects VIRTIO is also made to select VIRTIO_RING; just make them synonymous, since we removed the indirection layer some time ago. Signed-off-by: Rusty Russell

virtio: add help to CONFIG_VIRTIO option.

2012-09-28T05:35:15Z

Trying to enable a virtio driver (eg CONFIG_VIRTIO_BLK) is painful because it depends on CONFIG_VIRTIO. CONFIG_VIRTIO doesn't tell you how to turn it on (it's selected from anything which provides a virtio bus). This patch at least adds some documentation, visible in menuconfig, as a hint. Reported-by: Kent Overstreet Signed-off-by: Rusty Russell

virtio: support reserved vqs

2012-09-28T05:35:15Z

virtio network device multiqueue support reserves vq 3 for future use (useful both for future extensions and to make it pretty - this way receive vqs have even and transmit - odd numbers). Make it possible to skip initialization for specific vq numbers by specifying NULL for name. Document this usage as well as (existing) NULL callback. Drivers using this not coded up yet, so I simply tested with virtio-pci and verified that this patch does not break existing drivers. Signed-off-by: Michael S. Tsirkin Signed-off-by: Rusty Russell

virtio: introduce an API to set affinity for a virtqueue

2012-09-28T05:35:15Z

Sometimes, virtio device need to configure irq affinity hint to maximize the performance. Instead of just exposing the irq of a virtqueue, this patch introduce an API to set the affinity for a virtqueue. The api is best-effort, the affinity hint may not be set as expected due to platform support, irq sharing or irq type. Currently, only pci method were implemented and we set the affinity according to: - if device uses INTX, we just ignore the request - if device has per vq vector, we force the affinity hint - if the virtqueues share MSI, make the affinity OR over all affinities requested Signed-off-by: Jason Wang Signed-off-by: Paolo Bonzini Signed-off-by: Rusty Russell

virtio-ring: move queue_index to vring_virtqueue

2012-09-28T05:35:15Z

Instead of storing the queue index in transport-specific virtio structs, this patch moves them to vring_virtqueue and introduces an helper to get the value. This lets drivers simplify their management and tracing of virtqueues. Signed-off-by: Jason Wang Signed-off-by: Paolo Bonzini Signed-off-by: Rusty Russell