Commit Graph

5 Commits

Author SHA1 Message Date
Jean-Philippe Brucker 3f84b96c97 iommu/virtio: Fix sparse warning
We copied the virtio_iommu_config from the virtio-iommu specification,
which declares the fields using little-endian annotations (for example
le32). Unfortunately this causes sparse to warn about comparison between
little- and cpu-endian, because of the typecheck() in virtio_cread():

drivers/iommu/virtio-iommu.c:1024:9: sparse: sparse: incompatible types in comparison expression (different base types):
drivers/iommu/virtio-iommu.c:1024:9: sparse:    restricted __le64 *
drivers/iommu/virtio-iommu.c:1024:9: sparse:    unsigned long long *
drivers/iommu/virtio-iommu.c:1036:9: sparse: sparse: incompatible types in comparison expression (different base types):
drivers/iommu/virtio-iommu.c:1036:9: sparse:    restricted __le64 *
drivers/iommu/virtio-iommu.c:1036:9: sparse:    unsigned long long *
drivers/iommu/virtio-iommu.c:1040:9: sparse: sparse: incompatible types in comparison expression (different base types):
drivers/iommu/virtio-iommu.c:1040:9: sparse:    restricted __le64 *
drivers/iommu/virtio-iommu.c:1040:9: sparse:    unsigned long long *
drivers/iommu/virtio-iommu.c:1044:9: sparse: sparse: incompatible types in comparison expression (different base types):
drivers/iommu/virtio-iommu.c:1044:9: sparse:    restricted __le32 *
drivers/iommu/virtio-iommu.c:1044:9: sparse:    unsigned int *
drivers/iommu/virtio-iommu.c:1048:9: sparse: sparse: incompatible types in comparison expression (different base types):
drivers/iommu/virtio-iommu.c:1048:9: sparse:    restricted __le32 *
drivers/iommu/virtio-iommu.c:1048:9: sparse:    unsigned int *
drivers/iommu/virtio-iommu.c:1052:9: sparse: sparse: incompatible types in comparison expression (different base types):
drivers/iommu/virtio-iommu.c:1052:9: sparse:    restricted __le32 *
drivers/iommu/virtio-iommu.c:1052:9: sparse:    unsigned int *

Although virtio_cread() does convert virtio-endian (in our case
little-endian) to cpu-endian, the typecheck() needs the two arguments to
have the same endianness. Do as UAPI headers of other virtio devices do,
and remove the endian annotation from the device config.

Even though we change the UAPI this shouldn't cause any regression since
QEMU, the existing implementation of virtio-iommu that uses this header,
already removes the annotations when importing headers.

Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Link: https://lore.kernel.org/r/20200326093558.2641019-2-jean-philippe@linaro.org
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2020-03-27 11:09:18 +01:00
Jean-Philippe Brucker ae24fb49d0 iommu/virtio: Update to most recent specification
Following specification review a few things were changed in v8 of the
virtio-iommu series [1], but have been omitted when merging the base
driver. Add them now:

* Remove the EXEC flag.
* Add feature bit for the MMIO flag.
* Change domain_bits to domain_range.
* Add NOMEM status flag.

[1] https://lore.kernel.org/linux-iommu/20190530170929.19366-1-jean-philippe.brucker@arm.com/

Fixes: edcd69ab9a ("iommu: Add virtio-iommu driver")
Reported-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Acked-by: Joerg Roedel <jroedel@suse.de>
2019-07-22 11:52:27 -04:00
Jean-Philippe Brucker 169a126c6e iommu/virtio: Add event queue
The event queue offers a way for the device to report access faults from
endpoints. It is implemented on virtqueue #1. Whenever the host needs to
signal a fault, it fills one of the buffers offered by the guest and
interrupts it.

Tested-by: Bharat Bhushan <bharat.bhushan@nxp.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Jean-Philippe Brucker <jean-philippe.brucker@arm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-06-06 17:32:14 -04:00
Jean-Philippe Brucker 2a5a314874 iommu/virtio: Add probe request
When the device offers the probe feature, send a probe request for each
device managed by the IOMMU. Extract RESV_MEM information. When we
encounter a MSI doorbell region, set it up as a IOMMU_RESV_MSI region.
This will tell other subsystems that there is no need to map the MSI
doorbell in the virtio-iommu, because MSIs bypass it.

Tested-by: Bharat Bhushan <bharat.bhushan@nxp.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Jean-Philippe Brucker <jean-philippe.brucker@arm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-06-06 17:32:14 -04:00
Jean-Philippe Brucker edcd69ab9a iommu: Add virtio-iommu driver
The virtio IOMMU is a para-virtualized device, allowing to send IOMMU
requests such as map/unmap over virtio transport without emulating page
tables. This implementation handles ATTACH, DETACH, MAP and UNMAP
requests.

The bulk of the code transforms calls coming from the IOMMU API into
corresponding virtio requests. Mappings are kept in an interval tree
instead of page tables. A little more work is required for modular and x86
support, so for the moment the driver depends on CONFIG_VIRTIO=y and
CONFIG_ARM64.

Tested-by: Bharat Bhushan <bharat.bhushan@nxp.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Jean-Philippe Brucker <jean-philippe.brucker@arm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-06-06 17:32:13 -04:00