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| author | John Garry <john.garry@huawei.com> | 2022-07-14 19:15:25 +0800 |
|---|---|---|
| committer | Christoph Hellwig <hch@lst.de> | 2022-07-19 06:05:45 +0200 |
| commit | 6d9870b7e5def2450e21316515b9efc0529204dd (patch) | |
| tree | abaca6c6f44208643e0c36705199c3ff9ff0dc80 /drivers/iommu/dma-iommu.c | |
| parent | a229cc14f3395311b899e5e582b71efa8dd01df0 (diff) | |
| download | lwn-6d9870b7e5def2450e21316515b9efc0529204dd.tar.gz lwn-6d9870b7e5def2450e21316515b9efc0529204dd.zip | |
dma-iommu: add iommu_dma_opt_mapping_size()
Add the IOMMU callback for DMA mapping API dma_opt_mapping_size(), which
allows the drivers to know the optimal mapping limit and thus limit the
requested IOVA lengths.
This value is based on the IOVA rcache range limit, as IOVAs allocated
above this limit must always be newly allocated, which may be quite slow.
Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Acked-by: Robin Murphy <robin.murphy@arm.com>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Diffstat (limited to 'drivers/iommu/dma-iommu.c')
| -rw-r--r-- | drivers/iommu/dma-iommu.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c index f90251572a5d..9e1586447ee8 100644 --- a/drivers/iommu/dma-iommu.c +++ b/drivers/iommu/dma-iommu.c @@ -1459,6 +1459,11 @@ static unsigned long iommu_dma_get_merge_boundary(struct device *dev) return (1UL << __ffs(domain->pgsize_bitmap)) - 1; } +static size_t iommu_dma_opt_mapping_size(void) +{ + return iova_rcache_range(); +} + static const struct dma_map_ops iommu_dma_ops = { .alloc = iommu_dma_alloc, .free = iommu_dma_free, @@ -1479,6 +1484,7 @@ static const struct dma_map_ops iommu_dma_ops = { .map_resource = iommu_dma_map_resource, .unmap_resource = iommu_dma_unmap_resource, .get_merge_boundary = iommu_dma_get_merge_boundary, + .opt_mapping_size = iommu_dma_opt_mapping_size, }; /* |