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authorChristoph Hellwig <hch@lst.de>2020-09-01 13:59:45 +0200
committerChristoph Hellwig <hch@lst.de>2020-09-25 06:20:47 +0200
commitde7cf917768f438aae6d2f4e9bced3739f15f5b6 (patch)
treeded43ac607a6825a0e1d73e1b199568b005f7905 /kernel/dma
parentdma-mapping: add a new dma_alloc_pages API (diff)
downloadlinux-de7cf917768f438aae6d2f4e9bced3739f15f5b6.tar.xz
linux-de7cf917768f438aae6d2f4e9bced3739f15f5b6.zip
dma-mapping: add new {alloc,free}_noncoherent dma_map_ops methods
This will allow IOMMU drivers to allocate non-contigous memory and return a vmapped virtual address. Signed-off-by: Christoph Hellwig <hch@lst.de>
Diffstat (limited to 'kernel/dma')
-rw-r--r--kernel/dma/mapping.c33
1 files changed, 27 insertions, 6 deletions
diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c
index 06115f59f4ff..9669550656a0 100644
--- a/kernel/dma/mapping.c
+++ b/kernel/dma/mapping.c
@@ -513,19 +513,40 @@ EXPORT_SYMBOL_GPL(dma_free_pages);
void *dma_alloc_noncoherent(struct device *dev, size_t size,
dma_addr_t *dma_handle, enum dma_data_direction dir, gfp_t gfp)
{
- struct page *page;
+ const struct dma_map_ops *ops = get_dma_ops(dev);
+ void *vaddr;
- page = dma_alloc_pages(dev, size, dma_handle, dir, gfp);
- if (!page)
- return NULL;
- return page_address(page);
+ if (!ops || !ops->alloc_noncoherent) {
+ struct page *page;
+
+ page = dma_alloc_pages(dev, size, dma_handle, dir, gfp);
+ if (!page)
+ return NULL;
+ return page_address(page);
+ }
+
+ size = PAGE_ALIGN(size);
+ vaddr = ops->alloc_noncoherent(dev, size, dma_handle, dir, gfp);
+ if (vaddr)
+ debug_dma_map_page(dev, virt_to_page(vaddr), 0, size, dir,
+ *dma_handle);
+ return vaddr;
}
EXPORT_SYMBOL_GPL(dma_alloc_noncoherent);
void dma_free_noncoherent(struct device *dev, size_t size, void *vaddr,
dma_addr_t dma_handle, enum dma_data_direction dir)
{
- dma_free_pages(dev, size, virt_to_page(vaddr), dma_handle, dir);
+ const struct dma_map_ops *ops = get_dma_ops(dev);
+
+ if (!ops || !ops->free_noncoherent) {
+ dma_free_pages(dev, size, virt_to_page(vaddr), dma_handle, dir);
+ return;
+ }
+
+ size = PAGE_ALIGN(size);
+ debug_dma_unmap_page(dev, dma_handle, size, dir);
+ ops->free_noncoherent(dev, size, vaddr, dma_handle, dir);
}
EXPORT_SYMBOL_GPL(dma_free_noncoherent);