linux-toradex.git/drivers/virtio/virtio_pci.c, branch tegra-10.9.9

virtio-pci: fix per-vq MSI-X request logic

2009-10-28T22:20:36+00:00

Commit f68d24082e22ccee3077d11aeb6dc5354f0ca7f1
in 2.6.32-rc1 broke requesting IRQs for per-VQ MSI-X vectors:
- vector number was used instead of the vector itself
- we try to request an IRQ for VQ which does not
  have a callback handler

This is a regression that causes warnings in kernel log,
potentially lower performance as we need to scan vq list,
and might cause system failure if the interrupt
requested is in fact needed by another system.

This was not noticed earlier because in most cases
we were falling back on shared interrupt for all vqs.

The warnings often look like this:

virtio-pci 0000:00:03.0: irq 26 for MSI/MSI-X
virtio-pci 0000:00:03.0: irq 27 for MSI/MSI-X
virtio-pci 0000:00:03.0: irq 28 for MSI/MSI-X
IRQ handler type mismatch for IRQ 1
current handler: i8042
Pid: 2400, comm: modprobe Tainted: G        W
2.6.32-rc3-11952-gf3ed8d8-dirty #1
Call Trace:
 [] ? __setup_irq+0x299/0x304
 [] ? request_threaded_irq+0x144/0x1c1
 [] ? vring_interrupt+0x0/0x30
 [] ? vp_try_to_find_vqs+0x583/0x5c7
 [] ? skb_recv_done+0x0/0x34 [virtio_net]
 [] ? vp_find_vqs+0x2d/0x83
 [] ? vp_get+0x3c/0x4e
 [] ? virtnet_probe+0x2f1/0x428 [virtio_net]
 [] ? skb_recv_done+0x0/0x34 [virtio_net]
 [] ? skb_xmit_done+0x0/0x39 [virtio_net]
 [] ? sysfs_do_create_link+0xcb/0x116
 [] ? vp_get_status+0x14/0x16
 [] ? virtio_dev_probe+0xa9/0xc8
 [] ? driver_probe_device+0x8d/0x128
 [] ? __driver_attach+0x4f/0x6f
 [] ? __driver_attach+0x0/0x6f
 [] ? bus_for_each_dev+0x43/0x74
 [] ? bus_add_driver+0xea/0x22d
 [] ? driver_register+0xa7/0x111
 [] ? init+0x0/0xc [virtio_net]
 [] ? do_one_initcall+0x50/0x148
 [] ? sys_init_module+0xc5/0x21a
 [] ? system_call_fastpath+0x16/0x1b
virtio-pci 0000:00:03.0: irq 26 for MSI/MSI-X
virtio-pci 0000:00:03.0: irq 27 for MSI/MSI-X

Reported-by: Marcelo Tosatti 
Reported-by: Shirley Ma 
Signed-off-by: Michael S. Tsirkin 
Signed-off-by: Rusty Russell

virtio_pci: minor MSI-X cleanups

2009-09-23T12:56:31+00:00

1) Rename vp_request_vectors to vp_request_msix_vectors, and take
   non-MSI-X case out to caller.
2) Comment weird pci_enable_msix API
3) Rename vp_find_vq to setup_vq.
4) Fix spaces to tabs
5) Make nvectors calc internal to vp_try_to_find_vqs()
6) Rename vector to msix_vector for more clarity.

Signed-off-by: Rusty Russell 
Cc: "Michael S. Tsirkin"

virtio: refactor find_vqs

2009-07-30T06:33:45+00:00

This refactors find_vqs, making it more readable and robust, and fixing
two regressions from 2.6.30:
- double free_irq causing BUG_ON on device removal
- probe failure when vq can't be assigned to msi-x vector
  (reported on old host kernels)

Tested-by: Amit Shah 
Signed-off-by: Michael S. Tsirkin 
Signed-off-by: Rusty Russell

virtio: delete vq from list

2009-07-30T06:33:44+00:00

This makes delete vq the reverse of find vq.
This is required to make it possible to retry find_vqs
after a failure, otherwise the list gets corrupted.

Signed-off-by: Michael S. Tsirkin 
Signed-off-by: Rusty Russell

virtio: fix memory leak on device removal

2009-07-30T06:33:44+00:00

Make vp_free_vectors do the reverse of vq_request_vectors.

Signed-off-by: Michael S. Tsirkin 
Signed-off-by: Rusty Russell

virtio-pci: correctly unregister root device on error

2009-07-17T12:17:47+00:00

If pci_register_driver() fails we're incorrectly unregistering the root
device with device_unregister() rather than root_device_unregister().

Reported-by: Don Zickus 
Signed-off-by: Mark McLoughlin 
Signed-off-by: Rusty Russell

virtio_pci: optional MSI-X support

2009-06-12T12:46:37+00:00

This implements optional MSI-X support in virtio_pci.
MSI-X is used whenever the host supports at least 2 MSI-X
vectors: 1 for configuration changes and 1 for virtqueues.
Per-virtqueue vectors are allocated if enough vectors
available.

Signed-off-by: Michael S. Tsirkin 
Acked-by: Anthony Liguori 
Signed-off-by: Rusty Russell  (+ whitespace, style)

virtio_pci: split up vp_interrupt

2009-06-12T12:46:37+00:00

This reorganizes virtio-pci code in vp_interrupt slightly, so that
it's easier to add per-vq MSI support on top.

Signed-off-by: Michael S. Tsirkin 
Signed-off-by: Rusty Russell

virtio: find_vqs/del_vqs virtio operations

2009-06-12T12:46:36+00:00

This replaces find_vq/del_vq with find_vqs/del_vqs virtio operations,
and updates all drivers. This is needed for MSI support, because MSI
needs to know the total number of vectors upfront.

Signed-off-by: Michael S. Tsirkin 
Signed-off-by: Rusty Russell  (+ lguest/9p compile fixes)

virtio: add names to virtqueue struct, mapping from devices to queues.

2009-06-12T12:46:36+00:00

Add a linked list of all virtqueues for a virtio device: this helps for
debugging and is also needed for upcoming interface change.

Also, add a "name" field for clearer debug messages.

Signed-off-by: Rusty Russell