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 <amit.shah@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
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 <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Make vp_free_vectors do the reverse of vq_request_vectors.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
If pci_register_driver() fails we're incorrectly unregistering the root
device with device_unregister() rather than root_device_unregister().
Reported-by: Don Zickus <dzickus@redhat.com>
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This patch allows a virtio driver to use VIRTIO_DEV_ANY_ID for the
device id. This will be used by a test module that can be bound to
any virtio device.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This bug never appeared, since all current virtio drivers use
VIRTIO_DEV_ANY_ID for the vendor field. If a real vendor would be used,
the check in virtio_id_match is wrong - it returns 0 if
id->vendor == dev->id.vendor.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Add a new feature flag for indirect ring entries. These are ring
entries which point to a table of buffer descriptors.
The idea here is to increase the ring capacity by allowing a larger
effective ring size whereby the ring size dictates the number of
requests that may be outstanding, rather than the size of those
requests.
This should be most effective in the case of block I/O where we can
potentially benefit by concurrently dispatching a large number of
large requests. Even in the simple case of single segment block
requests, this results in a threefold increase in ring capacity.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
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 <mst@redhat.com>
Acked-by: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (+ whitespace, style)
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 <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
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 <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (+ lguest/9p compile fixes)
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 <rusty@rustcorp.com.au>
Virtio devices are supposed to negotiate features before they start using
the device, but the current code doesn't do this. This is because the
driver's probe() function invariably has to add buffers to a virtqueue,
or probe the disk (virtio_blk).
This currently doesn't matter since no existing backend is strict about
the feature negotiation. But it's possible to imagine a future feature
which completely changes how a device operates: in this case, we'd need
to acknowledge it before using the device.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Break out of wait_event_interruptible() if freezing has been requested,
in the vballoon thread. Without this change vballoon refuses to stop and
the system can't suspend.
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: stable@kernel.org
Impact: cleanup
Roel Kluin drew attention to these macros with his patch: here I
neaten them a little further:
1) Add a comment on what START_USE and END_USE are checking,
2) Brackets around _vq in BAD_RING,
3) Neaten formatting for START_USE so it's less than 80 cols.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Impact: cleanup
fix BAD_RING, START_US and END_USE macros
When these macros aren't called with a variable named vq as first
argument, this would result in a build failure.
Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
The host really shouldn't be notifying us of config changes
before the device status is VIRTIO_CONFIG_S_DRIVER or
VIRTIO_CONFIG_S_DRIVER_OK.
However, if we do happen to be interrupted while we're not
attached to a driver, we really shouldn't oops. Prevent
this simply by checking that device->driver is non-NULL
before trying to notify the driver of config changes.
Problem observed by doing a "set_link virtio.0 down" with
QEMU before the net driver had been loaded.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We shouldn't be statically allocating the root device object,
so dynamically allocate it using root_device_register()
instead.
Also avoids this warning from 'rmmod virtio_pci':
Device 'virtio-pci' does not have a release() function, it is broken and must be fixed
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Cc: Anthony Liguori <aliguori@us.ibm.com>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Add a release() function for virtio_pci devices so as to avoid:
Device 'virtio0' does not have a release() function, it is broken and must be fixed
Move the code to free the resources associated with the device
from virtio_pci_remove() into this new function. virtio_pci_remove()
now merely unregisters the device which should cause the final
ref to be dropped and virtio_pci_release_dev() to be called.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Reported-by: Michael Tokarev <mjt@tls.msk.ru>
Cc: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Make the balloon interface always use 4K pages, and convert Linux pfns if
necessary. This patch assumes that Linux's PAGE_SHIFT will never be less than
12.
Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (modified)
This allows each virtio user to hand in the alignment appropriate to
their virtio_ring structures.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
The virtio PCI devices don't depend on the guest page size. This matters
now PowerPC virtio is gaining ground (they like 64k pages).
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This patch is part of a larger patch series which will remove
the "char bus_id[20]" name string from struct device. The device
name is managed in the kobject anyway, and without any size
limitation, and just needlessly copied into "struct device".
To set and read the device name dev_name(dev) and dev_set_name(dev)
must be used. If your code uses static kobjects, which it shouldn't
do, "const char *init_name" can be used to statically provide the
name the registered device should have. At registration time, the
init_name field is cleared, to enforce the use of dev_name(dev) to
access the device name at a later time.
We need to get rid of all occurrences of bus_id in the entire tree
to be able to enable the new interface. Please apply this patch,
and possibly convert any remaining remaining occurrences of bus_id.
We want to submit a patch to -next, which will remove bus_id from
"struct device", to find the remaining pieces to convert, and finally
switch over to the new api, which will remove the 20 bytes array
and does no longer have a size limitation.
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
kzalloc() does not guarantee page alignment, and in fact this broke when
I enabled CONFIG_SLUB_DEBUG_ON.
(Thanks to Anthony Liguori for spotting the missing kfree sub)
Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (fixed kfree)
Tested-by: Anthony Liguori <aliguori@us.ibm.com>
