diff options
| author | Robin Murphy <robin.murphy@arm.com> | 2023-11-24 21:10:03 +0300 |
|---|---|---|
| committer | Christoph Hellwig <hch@lst.de> | 2023-12-15 14:32:42 +0300 |
| commit | 4ad4c1f394b84f9941a10aa8aaf11102478a390b (patch) | |
| tree | dd8752f43b26d9a042f2124b2d1b7551e0a83d95 /include/linux/dma-direct.h | |
| parent | 3f7168591ebf7bbdb91797d02b1afaf00a4289b1 (diff) | |
| download | linux-4ad4c1f394b84f9941a10aa8aaf11102478a390b.tar.xz | |
dma-mapping: don't store redundant offsets
A bus_dma_region necessarily stores both CPU and DMA base addresses for
a range, so there's no need to also store the difference between them.
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Diffstat (limited to 'include/linux/dma-direct.h')
| -rw-r--r-- | include/linux/dma-direct.h | 19 |
1 files changed, 12 insertions, 7 deletions
diff --git a/include/linux/dma-direct.h b/include/linux/dma-direct.h index 18aade195884..3eb3589ff43e 100644 --- a/include/linux/dma-direct.h +++ b/include/linux/dma-direct.h @@ -21,7 +21,6 @@ struct bus_dma_region { phys_addr_t cpu_start; dma_addr_t dma_start; u64 size; - u64 offset; }; static inline dma_addr_t translate_phys_to_dma(struct device *dev, @@ -29,9 +28,12 @@ static inline dma_addr_t translate_phys_to_dma(struct device *dev, { const struct bus_dma_region *m; - for (m = dev->dma_range_map; m->size; m++) - if (paddr >= m->cpu_start && paddr - m->cpu_start < m->size) - return (dma_addr_t)paddr - m->offset; + for (m = dev->dma_range_map; m->size; m++) { + u64 offset = paddr - m->cpu_start; + + if (paddr >= m->cpu_start && offset < m->size) + return m->dma_start + offset; + } /* make sure dma_capable fails when no translation is available */ return DMA_MAPPING_ERROR; @@ -42,9 +44,12 @@ static inline phys_addr_t translate_dma_to_phys(struct device *dev, { const struct bus_dma_region *m; - for (m = dev->dma_range_map; m->size; m++) - if (dma_addr >= m->dma_start && dma_addr - m->dma_start < m->size) - return (phys_addr_t)dma_addr + m->offset; + for (m = dev->dma_range_map; m->size; m++) { + u64 offset = dma_addr - m->dma_start; + + if (dma_addr >= m->dma_start && offset < m->size) + return m->cpu_start + offset; + } return (phys_addr_t)-1; } |