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-rw-r--r--kernel/dma/swiotlb.c232
1 files changed, 13 insertions, 219 deletions
diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index 2e126bac5d7d..d6361776dc5c 100644
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -21,7 +21,6 @@
#include <linux/cache.h>
#include <linux/dma-direct.h>
-#include <linux/dma-noncoherent.h>
#include <linux/mm.h>
#include <linux/export.h>
#include <linux/spinlock.h>
@@ -65,7 +64,7 @@ enum swiotlb_force swiotlb_force;
* swiotlb_tbl_sync_single_*, to see if the memory was in fact allocated by this
* API.
*/
-static phys_addr_t io_tlb_start, io_tlb_end;
+phys_addr_t io_tlb_start, io_tlb_end;
/*
* The number of IO TLB blocks (in groups of 64) between io_tlb_start and
@@ -383,11 +382,6 @@ void __init swiotlb_exit(void)
max_segment = 0;
}
-static int is_swiotlb_buffer(phys_addr_t paddr)
-{
- return paddr >= io_tlb_start && paddr < io_tlb_end;
-}
-
/*
* Bounce: copy the swiotlb buffer back to the original dma location
*/
@@ -623,221 +617,36 @@ void swiotlb_tbl_sync_single(struct device *hwdev, phys_addr_t tlb_addr,
}
}
-static dma_addr_t swiotlb_bounce_page(struct device *dev, phys_addr_t *phys,
+/*
+ * Create a swiotlb mapping for the buffer at @phys, and in case of DMAing
+ * to the device copy the data into it as well.
+ */
+bool swiotlb_map(struct device *dev, phys_addr_t *phys, dma_addr_t *dma_addr,
size_t size, enum dma_data_direction dir, unsigned long attrs)
{
- dma_addr_t dma_addr;
+ trace_swiotlb_bounced(dev, *dma_addr, size, swiotlb_force);
if (unlikely(swiotlb_force == SWIOTLB_NO_FORCE)) {
dev_warn_ratelimited(dev,
"Cannot do DMA to address %pa\n", phys);
- return DMA_MAPPING_ERROR;
+ return false;
}
/* Oh well, have to allocate and map a bounce buffer. */
*phys = swiotlb_tbl_map_single(dev, __phys_to_dma(dev, io_tlb_start),
*phys, size, dir, attrs);
if (*phys == DMA_MAPPING_ERROR)
- return DMA_MAPPING_ERROR;
+ return false;
/* Ensure that the address returned is DMA'ble */
- dma_addr = __phys_to_dma(dev, *phys);
- if (unlikely(!dma_capable(dev, dma_addr, size))) {
+ *dma_addr = __phys_to_dma(dev, *phys);
+ if (unlikely(!dma_capable(dev, *dma_addr, size))) {
swiotlb_tbl_unmap_single(dev, *phys, size, dir,
attrs | DMA_ATTR_SKIP_CPU_SYNC);
- return DMA_MAPPING_ERROR;
- }
-
- return dma_addr;
-}
-
-/*
- * Map a single buffer of the indicated size for DMA in streaming mode. The
- * physical address to use is returned.
- *
- * Once the device is given the dma address, the device owns this memory until
- * either swiotlb_unmap_page or swiotlb_dma_sync_single is performed.
- */
-dma_addr_t swiotlb_map_page(struct device *dev, struct page *page,
- unsigned long offset, size_t size,
- enum dma_data_direction dir,
- unsigned long attrs)
-{
- phys_addr_t phys = page_to_phys(page) + offset;
- dma_addr_t dev_addr = phys_to_dma(dev, phys);
-
- BUG_ON(dir == DMA_NONE);
- /*
- * If the address happens to be in the device's DMA window,
- * we can safely return the device addr and not worry about bounce
- * buffering it.
- */
- if (!dma_capable(dev, dev_addr, size) ||
- swiotlb_force == SWIOTLB_FORCE) {
- trace_swiotlb_bounced(dev, dev_addr, size, swiotlb_force);
- dev_addr = swiotlb_bounce_page(dev, &phys, size, dir, attrs);
+ return false;
}
- if (!dev_is_dma_coherent(dev) &&
- (attrs & DMA_ATTR_SKIP_CPU_SYNC) == 0 &&
- dev_addr != DMA_MAPPING_ERROR)
- arch_sync_dma_for_device(dev, phys, size, dir);
-
- return dev_addr;
-}
-
-/*
- * Unmap a single streaming mode DMA translation. The dma_addr and size must
- * match what was provided for in a previous swiotlb_map_page call. All
- * other usages are undefined.
- *
- * After this call, reads by the cpu to the buffer are guaranteed to see
- * whatever the device wrote there.
- */
-void swiotlb_unmap_page(struct device *hwdev, dma_addr_t dev_addr,
- size_t size, enum dma_data_direction dir,
- unsigned long attrs)
-{
- phys_addr_t paddr = dma_to_phys(hwdev, dev_addr);
-
- BUG_ON(dir == DMA_NONE);
-
- if (!dev_is_dma_coherent(hwdev) &&
- (attrs & DMA_ATTR_SKIP_CPU_SYNC) == 0)
- arch_sync_dma_for_cpu(hwdev, paddr, size, dir);
-
- if (is_swiotlb_buffer(paddr))
- swiotlb_tbl_unmap_single(hwdev, paddr, size, dir, attrs);
-}
-
-/*
- * Make physical memory consistent for a single streaming mode DMA translation
- * after a transfer.
- *
- * If you perform a swiotlb_map_page() but wish to interrogate the buffer
- * using the cpu, yet do not wish to teardown the dma mapping, you must
- * call this function before doing so. At the next point you give the dma
- * address back to the card, you must first perform a
- * swiotlb_dma_sync_for_device, and then the device again owns the buffer
- */
-static void
-swiotlb_sync_single(struct device *hwdev, dma_addr_t dev_addr,
- size_t size, enum dma_data_direction dir,
- enum dma_sync_target target)
-{
- phys_addr_t paddr = dma_to_phys(hwdev, dev_addr);
-
- BUG_ON(dir == DMA_NONE);
-
- if (!dev_is_dma_coherent(hwdev) && target == SYNC_FOR_CPU)
- arch_sync_dma_for_cpu(hwdev, paddr, size, dir);
-
- if (is_swiotlb_buffer(paddr))
- swiotlb_tbl_sync_single(hwdev, paddr, size, dir, target);
-
- if (!dev_is_dma_coherent(hwdev) && target == SYNC_FOR_DEVICE)
- arch_sync_dma_for_device(hwdev, paddr, size, dir);
-}
-
-void
-swiotlb_sync_single_for_cpu(struct device *hwdev, dma_addr_t dev_addr,
- size_t size, enum dma_data_direction dir)
-{
- swiotlb_sync_single(hwdev, dev_addr, size, dir, SYNC_FOR_CPU);
-}
-
-void
-swiotlb_sync_single_for_device(struct device *hwdev, dma_addr_t dev_addr,
- size_t size, enum dma_data_direction dir)
-{
- swiotlb_sync_single(hwdev, dev_addr, size, dir, SYNC_FOR_DEVICE);
-}
-
-/*
- * Map a set of buffers described by scatterlist in streaming mode for DMA.
- * This is the scatter-gather version of the above swiotlb_map_page
- * interface. Here the scatter gather list elements are each tagged with the
- * appropriate dma address and length. They are obtained via
- * sg_dma_{address,length}(SG).
- *
- * Device ownership issues as mentioned above for swiotlb_map_page are the
- * same here.
- */
-int
-swiotlb_map_sg_attrs(struct device *dev, struct scatterlist *sgl, int nelems,
- enum dma_data_direction dir, unsigned long attrs)
-{
- struct scatterlist *sg;
- int i;
-
- for_each_sg(sgl, sg, nelems, i) {
- sg->dma_address = swiotlb_map_page(dev, sg_page(sg), sg->offset,
- sg->length, dir, attrs);
- if (sg->dma_address == DMA_MAPPING_ERROR)
- goto out_error;
- sg_dma_len(sg) = sg->length;
- }
-
- return nelems;
-
-out_error:
- swiotlb_unmap_sg_attrs(dev, sgl, i, dir,
- attrs | DMA_ATTR_SKIP_CPU_SYNC);
- sg_dma_len(sgl) = 0;
- return 0;
-}
-
-/*
- * Unmap a set of streaming mode DMA translations. Again, cpu read rules
- * concerning calls here are the same as for swiotlb_unmap_page() above.
- */
-void
-swiotlb_unmap_sg_attrs(struct device *hwdev, struct scatterlist *sgl,
- int nelems, enum dma_data_direction dir,
- unsigned long attrs)
-{
- struct scatterlist *sg;
- int i;
-
- BUG_ON(dir == DMA_NONE);
-
- for_each_sg(sgl, sg, nelems, i)
- swiotlb_unmap_page(hwdev, sg->dma_address, sg_dma_len(sg), dir,
- attrs);
-}
-
-/*
- * Make physical memory consistent for a set of streaming mode DMA translations
- * after a transfer.
- *
- * The same as swiotlb_sync_single_* but for a scatter-gather list, same rules
- * and usage.
- */
-static void
-swiotlb_sync_sg(struct device *hwdev, struct scatterlist *sgl,
- int nelems, enum dma_data_direction dir,
- enum dma_sync_target target)
-{
- struct scatterlist *sg;
- int i;
-
- for_each_sg(sgl, sg, nelems, i)
- swiotlb_sync_single(hwdev, sg->dma_address,
- sg_dma_len(sg), dir, target);
-}
-
-void
-swiotlb_sync_sg_for_cpu(struct device *hwdev, struct scatterlist *sg,
- int nelems, enum dma_data_direction dir)
-{
- swiotlb_sync_sg(hwdev, sg, nelems, dir, SYNC_FOR_CPU);
-}
-
-void
-swiotlb_sync_sg_for_device(struct device *hwdev, struct scatterlist *sg,
- int nelems, enum dma_data_direction dir)
-{
- swiotlb_sync_sg(hwdev, sg, nelems, dir, SYNC_FOR_DEVICE);
+ return true;
}
/*
@@ -851,18 +660,3 @@ swiotlb_dma_supported(struct device *hwdev, u64 mask)
{
return __phys_to_dma(hwdev, io_tlb_end - 1) <= mask;
}
-
-const struct dma_map_ops swiotlb_dma_ops = {
- .alloc = dma_direct_alloc,
- .free = dma_direct_free,
- .sync_single_for_cpu = swiotlb_sync_single_for_cpu,
- .sync_single_for_device = swiotlb_sync_single_for_device,
- .sync_sg_for_cpu = swiotlb_sync_sg_for_cpu,
- .sync_sg_for_device = swiotlb_sync_sg_for_device,
- .map_sg = swiotlb_map_sg_attrs,
- .unmap_sg = swiotlb_unmap_sg_attrs,
- .map_page = swiotlb_map_page,
- .unmap_page = swiotlb_unmap_page,
- .dma_supported = dma_direct_supported,
-};
-EXPORT_SYMBOL(swiotlb_dma_ops);