diff options
| author | Robin Murphy <robin.murphy@arm.com> | 2018-12-06 22:20:49 +0100 |
|---|---|---|
| committer | Christoph Hellwig <hch@lst.de> | 2018-12-13 21:06:13 +0100 |
| commit | e5361ca29f2fea345c08d2b5cb5e3b1840cbafb8 (patch) | |
| tree | 697be029cf1427e187d1547d376c719b185b632b /drivers/acpi/scan.c | |
| parent | dma-mapping: factor out dummy DMA ops (diff) | |
| download | linux-e5361ca29f2fea345c08d2b5cb5e3b1840cbafb8.tar.xz linux-e5361ca29f2fea345c08d2b5cb5e3b1840cbafb8.zip | |
ACPI / scan: Refactor _CCA enforcement
Rather than checking the DMA attribute at each callsite, just pass it
through for acpi_dma_configure() to handle directly. That can then deal
with the relatively exceptional DEV_DMA_NOT_SUPPORTED case by explicitly
installing dummy DMA ops instead of just skipping setup entirely. This
will then free up the dev->dma_ops == NULL case for some valuable
fastpath optimisations.
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Tested-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Tony Luck <tony.luck@intel.com>
Diffstat (limited to 'drivers/acpi/scan.c')
| -rw-r--r-- | drivers/acpi/scan.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c index bd1c59fb0e17..b75ae34ed188 100644 --- a/drivers/acpi/scan.c +++ b/drivers/acpi/scan.c @@ -1456,6 +1456,11 @@ int acpi_dma_configure(struct device *dev, enum dev_dma_attr attr) const struct iommu_ops *iommu; u64 dma_addr = 0, size = 0; + if (attr == DEV_DMA_NOT_SUPPORTED) { + set_dma_ops(dev, &dma_dummy_ops); + return 0; + } + iort_dma_setup(dev, &dma_addr, &size); iommu = iort_iommu_configure(dev); |