diff options
Diffstat (limited to 'kernel/dma')
| -rw-r--r-- | kernel/dma/direct.c | 44 | ||||
| -rw-r--r-- | kernel/dma/mapping.c | 18 |
2 files changed, 40 insertions, 22 deletions
diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c index b8fe0b3d0ffb..24c359d9c879 100644 --- a/kernel/dma/direct.c +++ b/kernel/dma/direct.c @@ -13,6 +13,7 @@ #include <linux/vmalloc.h> #include <linux/set_memory.h> #include <linux/slab.h> +#include <linux/pci-p2pdma.h> #include "direct.h" /* @@ -462,34 +463,33 @@ int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl, int nents, enum dma_data_direction dir, unsigned long attrs) { 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; + switch (pci_p2pdma_state(&p2pdma_state, dev, sg_page(sg))) { + 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. + */ + break; + case PCI_P2PDMA_MAP_NONE: + sg->dma_address = dma_direct_map_page(dev, sg_page(sg), + sg->offset, sg->length, dir, attrs); + if (sg->dma_address == DMA_MAPPING_ERROR) { + ret = -EIO; 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) { - ret = -EIO; + break; + case PCI_P2PDMA_MAP_BUS_ADDR: + sg->dma_address = pci_p2pdma_bus_addr_map(&p2pdma_state, + sg_phys(sg)); + sg_dma_mark_bus_address(sg); + continue; + default: + ret = -EREMOTEIO; goto out_unmap; } sg_dma_len(sg) = sg->length; diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c index 051a32988040..107e4a4d251d 100644 --- a/kernel/dma/mapping.c +++ b/kernel/dma/mapping.c @@ -443,6 +443,24 @@ bool __dma_need_sync(struct device *dev, dma_addr_t dma_addr) } EXPORT_SYMBOL_GPL(__dma_need_sync); +/** + * dma_need_unmap - does this device need dma_unmap_* operations + * @dev: device to check + * + * If this function returns %false, drivers can skip calling dma_unmap_* after + * finishing an I/O. This function must be called after all mappings that might + * need to be unmapped have been performed. + */ +bool dma_need_unmap(struct device *dev) +{ + if (!dma_map_direct(dev, get_dma_ops(dev))) + return true; + if (!dev->dma_skip_sync) + return true; + return IS_ENABLED(CONFIG_DMA_API_DEBUG); +} +EXPORT_SYMBOL_GPL(dma_need_unmap); + static void dma_setup_need_sync(struct device *dev) { const struct dma_map_ops *ops = get_dma_ops(dev); |