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authorChristoph Hellwig2018-01-09 16:30:23 +0100
committerChristoph Hellwig2018-01-15 09:35:06 +0100
commit002e67454f61bb67d8071ac4d0cacb86a01d18e0 (patch)
treeef15f40222144d529cc2e2b2bfdb72fad7fd4510 /lib/dma-noop.c
parentdma-mapping: provide a generic asm/dma-mapping.h (diff)
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dma-direct: rename dma_noop to dma_direct
The trivial direct mapping implementation already does a virtual to physical translation which isn't strictly a noop, and will soon learn to do non-direct but linear physical to dma translations through the device offset and a few small tricks. Rename it to a better fitting name. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Vladimir Murzin <vladimir.murzin@arm.com>
Diffstat (limited to 'lib/dma-noop.c')
-rw-r--r--lib/dma-noop.c68
1 files changed, 0 insertions, 68 deletions
diff --git a/lib/dma-noop.c b/lib/dma-noop.c
deleted file mode 100644
index a10185b0c2d4..000000000000
--- a/lib/dma-noop.c
+++ /dev/null
@@ -1,68 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * lib/dma-noop.c
- *
- * DMA operations that map to physical addresses without flushing memory.
- */
-#include <linux/export.h>
-#include <linux/mm.h>
-#include <linux/dma-mapping.h>
-#include <linux/scatterlist.h>
-#include <linux/pfn.h>
-
-static void *dma_noop_alloc(struct device *dev, size_t size,
- dma_addr_t *dma_handle, gfp_t gfp,
- unsigned long attrs)
-{
- void *ret;
-
- ret = (void *)__get_free_pages(gfp, get_order(size));
- if (ret)
- *dma_handle = virt_to_phys(ret) - PFN_PHYS(dev->dma_pfn_offset);
-
- return ret;
-}
-
-static void dma_noop_free(struct device *dev, size_t size,
- void *cpu_addr, dma_addr_t dma_addr,
- unsigned long attrs)
-{
- free_pages((unsigned long)cpu_addr, get_order(size));
-}
-
-static dma_addr_t dma_noop_map_page(struct device *dev, struct page *page,
- unsigned long offset, size_t size,
- enum dma_data_direction dir,
- unsigned long attrs)
-{
- return page_to_phys(page) + offset - PFN_PHYS(dev->dma_pfn_offset);
-}
-
-static int dma_noop_map_sg(struct device *dev, struct scatterlist *sgl, int nents,
- enum dma_data_direction dir,
- unsigned long attrs)
-{
- int i;
- struct scatterlist *sg;
-
- for_each_sg(sgl, sg, nents, i) {
- dma_addr_t offset = PFN_PHYS(dev->dma_pfn_offset);
- void *va;
-
- BUG_ON(!sg_page(sg));
- va = sg_virt(sg);
- sg_dma_address(sg) = (dma_addr_t)virt_to_phys(va) - offset;
- sg_dma_len(sg) = sg->length;
- }
-
- return nents;
-}
-
-const struct dma_map_ops dma_noop_ops = {
- .alloc = dma_noop_alloc,
- .free = dma_noop_free,
- .map_page = dma_noop_map_page,
- .map_sg = dma_noop_map_sg,
-};
-
-EXPORT_SYMBOL(dma_noop_ops);