summaryrefslogtreecommitdiff
path: root/kernel/dma
diff options
context:
space:
mode:
authorChristoph Hellwig <hch@lst.de>2020-02-03 14:44:38 +0100
committerChristoph Hellwig <hch@lst.de>2020-02-05 18:53:05 +0100
commit4a47cbae04844f0c5e2365aa6c217b61850bb832 (patch)
tree4ee380c5b7c96f872ee8c9eda32f63297793262d /kernel/dma
parent91ef26f914171cf753330f13724fd9142b5b1640 (diff)
dma-direct: improve swiotlb error reporting
Untangle the way how dma_direct_map_page calls into swiotlb to be able to properly report errors where the swiotlb DMA address overflows the mask separately from overflows in the !swiotlb case. This means that siotlb_map now has to do a little more work that duplicates dma_direct_map_page, but doing so greatly simplifies the calling convention. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Diffstat (limited to 'kernel/dma')
-rw-r--r--kernel/dma/direct.c16
-rw-r--r--kernel/dma/swiotlb.c42
2 files changed, 30 insertions, 28 deletions
diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index 32ec69cdba54..594bddd04e01 100644
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -357,13 +357,6 @@ void dma_direct_unmap_sg(struct device *dev, struct scatterlist *sgl,
EXPORT_SYMBOL(dma_direct_unmap_sg);
#endif
-static inline bool dma_direct_possible(struct device *dev, dma_addr_t dma_addr,
- size_t size)
-{
- return swiotlb_force != SWIOTLB_FORCE &&
- dma_capable(dev, dma_addr, size, true);
-}
-
dma_addr_t dma_direct_map_page(struct device *dev, struct page *page,
unsigned long offset, size_t size, enum dma_data_direction dir,
unsigned long attrs)
@@ -371,8 +364,13 @@ dma_addr_t dma_direct_map_page(struct device *dev, struct page *page,
phys_addr_t phys = page_to_phys(page) + offset;
dma_addr_t dma_addr = phys_to_dma(dev, phys);
- if (unlikely(!dma_direct_possible(dev, dma_addr, size)) &&
- !swiotlb_map(dev, &phys, &dma_addr, size, dir, attrs)) {
+ if (unlikely(swiotlb_force == SWIOTLB_FORCE))
+ return swiotlb_map(dev, phys, size, dir, attrs);
+
+ if (unlikely(!dma_capable(dev, dma_addr, size, true))) {
+ if (swiotlb_force != SWIOTLB_NO_FORCE)
+ return swiotlb_map(dev, phys, size, dir, attrs);
+
report_addr(dev, dma_addr, size);
return DMA_MAPPING_ERROR;
}
diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index 9280d6f8271e..c19379fabd20 100644
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -22,6 +22,7 @@
#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>
@@ -656,35 +657,38 @@ void swiotlb_tbl_sync_single(struct device *hwdev, phys_addr_t tlb_addr,
}
/*
- * Create a swiotlb mapping for the buffer at @phys, and in case of DMAing
+ * Create a swiotlb mapping for the buffer at @paddr, 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 swiotlb_map(struct device *dev, phys_addr_t paddr, size_t size,
+ enum dma_data_direction dir, unsigned long attrs)
{
- trace_swiotlb_bounced(dev, *dma_addr, size, swiotlb_force);
+ phys_addr_t swiotlb_addr;
+ dma_addr_t dma_addr;
- if (unlikely(swiotlb_force == SWIOTLB_NO_FORCE)) {
- dev_warn_ratelimited(dev,
- "Cannot do DMA to address %pa\n", phys);
- return false;
- }
+ trace_swiotlb_bounced(dev, phys_to_dma(dev, paddr), size,
+ swiotlb_force);
- /* 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, size, dir, attrs);
- if (*phys == (phys_addr_t)DMA_MAPPING_ERROR)
- return false;
+ swiotlb_addr = swiotlb_tbl_map_single(dev,
+ __phys_to_dma(dev, io_tlb_start),
+ paddr, size, size, dir, attrs);
+ if (swiotlb_addr == (phys_addr_t)DMA_MAPPING_ERROR)
+ return DMA_MAPPING_ERROR;
/* Ensure that the address returned is DMA'ble */
- *dma_addr = __phys_to_dma(dev, *phys);
- if (unlikely(!dma_capable(dev, *dma_addr, size, true))) {
- swiotlb_tbl_unmap_single(dev, *phys, size, size, dir,
+ dma_addr = __phys_to_dma(dev, swiotlb_addr);
+ if (unlikely(!dma_capable(dev, dma_addr, size, true))) {
+ swiotlb_tbl_unmap_single(dev, swiotlb_addr, size, size, dir,
attrs | DMA_ATTR_SKIP_CPU_SYNC);
- return false;
+ dev_WARN_ONCE(dev, 1,
+ "swiotlb addr %pad+%zu overflow (mask %llx, bus limit %llx).\n",
+ &dma_addr, size, *dev->dma_mask, dev->bus_dma_limit);
+ return DMA_MAPPING_ERROR;
}
- return true;
+ if (!dev_is_dma_coherent(dev) && !(attrs & DMA_ATTR_SKIP_CPU_SYNC))
+ arch_sync_dma_for_device(swiotlb_addr, size, dir);
+ return dma_addr;
}
size_t swiotlb_max_mapping_size(struct device *dev)