diff options
| -rw-r--r-- | kernel/dma/direct.c | 43 | ||||
| -rw-r--r-- | kernel/dma/direct.h | 8 |
2 files changed, 44 insertions, 7 deletions
diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c index e978f36e6be8..133a4be2d3e5 100644 --- a/kernel/dma/direct.c +++ b/kernel/dma/direct.c @@ -454,29 +454,60 @@ void dma_direct_sync_sg_for_cpu(struct device *dev, arch_sync_dma_for_cpu_all(); } +/* + * Unmaps segments, except for ones marked as pci_p2pdma which do not + * require any further action as they contain a bus address. + */ void dma_direct_unmap_sg(struct device *dev, struct scatterlist *sgl, int nents, enum dma_data_direction dir, unsigned long attrs) { struct scatterlist *sg; int i; - for_each_sg(sgl, sg, nents, i) - dma_direct_unmap_page(dev, sg->dma_address, sg_dma_len(sg), dir, - attrs); + for_each_sg(sgl, sg, nents, i) { + if (sg_is_dma_bus_address(sg)) + sg_dma_unmark_bus_address(sg); + else + dma_direct_unmap_page(dev, sg->dma_address, + sg_dma_len(sg), dir, attrs); + } } #endif int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl, int nents, enum dma_data_direction dir, unsigned long attrs) { - int i; + struct pci_p2pdma_map_state p2pdma_state = {}; + enum pci_p2pdma_map_type map; struct scatterlist *sg; + int i, ret; for_each_sg(sgl, sg, nents, i) { + if (is_pci_p2pdma_page(sg_page(sg))) { + map = pci_p2pdma_map_segment(&p2pdma_state, dev, sg); + switch (map) { + case PCI_P2PDMA_MAP_BUS_ADDR: + continue; + case PCI_P2PDMA_MAP_THRU_HOST_BRIDGE: + /* + * Any P2P mapping that traverses the PCI + * host bridge must be mapped with CPU physical + * address and not PCI bus addresses. This is + * done with dma_direct_map_page() below. + */ + break; + default: + ret = -EREMOTEIO; + goto out_unmap; + } + } + sg->dma_address = dma_direct_map_page(dev, sg_page(sg), sg->offset, sg->length, dir, attrs); - if (sg->dma_address == DMA_MAPPING_ERROR) + if (sg->dma_address == DMA_MAPPING_ERROR) { + ret = -EIO; goto out_unmap; + } sg_dma_len(sg) = sg->length; } @@ -484,7 +515,7 @@ int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl, int nents, out_unmap: dma_direct_unmap_sg(dev, sgl, i, dir, attrs | DMA_ATTR_SKIP_CPU_SYNC); - return -EIO; + return ret; } dma_addr_t dma_direct_map_resource(struct device *dev, phys_addr_t paddr, diff --git a/kernel/dma/direct.h b/kernel/dma/direct.h index a78c0ba70645..e38ffc5e6bdd 100644 --- a/kernel/dma/direct.h +++ b/kernel/dma/direct.h @@ -8,6 +8,7 @@ #define _KERNEL_DMA_DIRECT_H #include <linux/dma-direct.h> +#include <linux/memremap.h> int dma_direct_get_sgtable(struct device *dev, struct sg_table *sgt, void *cpu_addr, dma_addr_t dma_addr, size_t size, @@ -87,10 +88,15 @@ static inline dma_addr_t dma_direct_map_page(struct device *dev, phys_addr_t phys = page_to_phys(page) + offset; dma_addr_t dma_addr = phys_to_dma(dev, phys); - if (is_swiotlb_force_bounce(dev)) + if (is_swiotlb_force_bounce(dev)) { + if (is_pci_p2pdma_page(page)) + return DMA_MAPPING_ERROR; return swiotlb_map(dev, phys, size, dir, attrs); + } if (unlikely(!dma_capable(dev, dma_addr, size, true))) { + if (is_pci_p2pdma_page(page)) + return DMA_MAPPING_ERROR; if (is_swiotlb_active(dev)) return swiotlb_map(dev, phys, size, dir, attrs); |