diff options
| author | Robin Murphy <robin.murphy@arm.com> | 2017-01-19 20:57:46 +0000 |
|---|---|---|
| committer | Will Deacon <will.deacon@arm.com> | 2017-01-23 11:48:16 +0000 |
| commit | fdbe574eb69312a7fbe09674d69c01b80e4ed9dc (patch) | |
| tree | 6c4cc7dd1fe4eb0188343281fb83572383ddb8dd /include/linux/dma-iommu.h | |
| parent | a121103c922847ba5010819a3f250f1f7fc84ab8 (diff) | |
iommu/dma: Allow MSI-only cookies
IOMMU domain users such as VFIO face a similar problem to DMA API ops
with regard to mapping MSI messages in systems where the MSI write is
subject to IOMMU translation. With the relevant infrastructure now in
place for managed DMA domains, it's actually really simple for other
users to piggyback off that and reap the benefits without giving up
their own IOVA management, and without having to reinvent their own
wheel in the MSI layer.
Allow such users to opt into automatic MSI remapping by dedicating a
region of their IOVA space to a managed cookie, and extend the mapping
routine to implement a trivial linear allocator in such cases, to avoid
the needless overhead of a full-blown IOVA domain.
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Tomasz Nowicki <tomasz.nowicki@caviumnetworks.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Tested-by: Tomasz Nowicki <tomasz.nowicki@caviumnetworks.com>
Tested-by: Bharat Bhushan <bharat.bhushan@nxp.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Diffstat (limited to 'include/linux/dma-iommu.h')
| -rw-r--r-- | include/linux/dma-iommu.h | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/include/linux/dma-iommu.h b/include/linux/dma-iommu.h index 7f7e9a7e3839..28df844a23b6 100644 --- a/include/linux/dma-iommu.h +++ b/include/linux/dma-iommu.h @@ -27,6 +27,7 @@ int iommu_dma_init(void); /* Domain management interface for IOMMU drivers */ int iommu_get_dma_cookie(struct iommu_domain *domain); +int iommu_get_msi_cookie(struct iommu_domain *domain, dma_addr_t base); void iommu_put_dma_cookie(struct iommu_domain *domain); /* Setup call for arch DMA mapping code */ @@ -86,6 +87,11 @@ static inline int iommu_get_dma_cookie(struct iommu_domain *domain) return -ENODEV; } +static inline int iommu_get_msi_cookie(struct iommu_domain *domain, dma_addr_t base) +{ + return -ENODEV; +} + static inline void iommu_put_dma_cookie(struct iommu_domain *domain) { } |