diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/dma/direct.c | 2 | ||||
| -rw-r--r-- | kernel/dma/swiotlb.c | 326 |
2 files changed, 62 insertions, 266 deletions
diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c index 87a6bc2a96c0..f14c376937e5 100644 --- a/kernel/dma/direct.c +++ b/kernel/dma/direct.c @@ -14,8 +14,6 @@ #include <linux/pfn.h> #include <linux/set_memory.h> -#define DIRECT_MAPPING_ERROR 0 - /* * Most architectures use ZONE_DMA for the first 16 Megabytes, but * some use it for entirely different regions: diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c index 4f8a6dbf0b60..ebecaf255ea2 100644 --- a/kernel/dma/swiotlb.c +++ b/kernel/dma/swiotlb.c @@ -21,6 +21,7 @@ #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> @@ -73,13 +74,6 @@ static phys_addr_t io_tlb_start, io_tlb_end; static unsigned long io_tlb_nslabs; /* - * When the IOMMU overflows we return a fallback buffer. This sets the size. - */ -static unsigned long io_tlb_overflow = 32*1024; - -static phys_addr_t io_tlb_overflow_buffer; - -/* * This is a free list describing the number of free entries available from * each index */ @@ -126,7 +120,6 @@ setup_io_tlb_npages(char *str) return 0; } early_param("swiotlb", setup_io_tlb_npages); -/* make io_tlb_overflow tunable too? */ unsigned long swiotlb_nr_tbl(void) { @@ -194,16 +187,10 @@ void __init swiotlb_update_mem_attributes(void) bytes = PAGE_ALIGN(io_tlb_nslabs << IO_TLB_SHIFT); set_memory_decrypted((unsigned long)vaddr, bytes >> PAGE_SHIFT); memset(vaddr, 0, bytes); - - vaddr = phys_to_virt(io_tlb_overflow_buffer); - bytes = PAGE_ALIGN(io_tlb_overflow); - set_memory_decrypted((unsigned long)vaddr, bytes >> PAGE_SHIFT); - memset(vaddr, 0, bytes); } int __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose) { - void *v_overflow_buffer; unsigned long i, bytes; bytes = nslabs << IO_TLB_SHIFT; @@ -213,17 +200,6 @@ int __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose) io_tlb_end = io_tlb_start + bytes; /* - * Get the overflow emergency buffer - */ - v_overflow_buffer = memblock_virt_alloc_low_nopanic( - PAGE_ALIGN(io_tlb_overflow), - PAGE_SIZE); - if (!v_overflow_buffer) - return -ENOMEM; - - io_tlb_overflow_buffer = __pa(v_overflow_buffer); - - /* * Allocate and initialize the free list array. This array is used * to find contiguous free memory regions of size up to IO_TLB_SEGSIZE * between io_tlb_start and io_tlb_end. @@ -330,7 +306,6 @@ int swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs) { unsigned long i, bytes; - unsigned char *v_overflow_buffer; bytes = nslabs << IO_TLB_SHIFT; @@ -342,19 +317,6 @@ swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs) memset(tlb, 0, bytes); /* - * Get the overflow emergency buffer - */ - v_overflow_buffer = (void *)__get_free_pages(GFP_DMA, - get_order(io_tlb_overflow)); - if (!v_overflow_buffer) - goto cleanup2; - - set_memory_decrypted((unsigned long)v_overflow_buffer, - io_tlb_overflow >> PAGE_SHIFT); - memset(v_overflow_buffer, 0, io_tlb_overflow); - io_tlb_overflow_buffer = virt_to_phys(v_overflow_buffer); - - /* * Allocate and initialize the free list array. This array is used * to find contiguous free memory regions of size up to IO_TLB_SEGSIZE * between io_tlb_start and io_tlb_end. @@ -390,10 +352,6 @@ cleanup4: sizeof(int))); io_tlb_list = NULL; cleanup3: - free_pages((unsigned long)v_overflow_buffer, - get_order(io_tlb_overflow)); - io_tlb_overflow_buffer = 0; -cleanup2: io_tlb_end = 0; io_tlb_start = 0; io_tlb_nslabs = 0; @@ -407,8 +365,6 @@ void __init swiotlb_exit(void) return; if (late_alloc) { - free_pages((unsigned long)phys_to_virt(io_tlb_overflow_buffer), - get_order(io_tlb_overflow)); free_pages((unsigned long)io_tlb_orig_addr, get_order(io_tlb_nslabs * sizeof(phys_addr_t))); free_pages((unsigned long)io_tlb_list, get_order(io_tlb_nslabs * @@ -416,8 +372,6 @@ void __init swiotlb_exit(void) free_pages((unsigned long)phys_to_virt(io_tlb_start), get_order(io_tlb_nslabs << IO_TLB_SHIFT)); } else { - memblock_free_late(io_tlb_overflow_buffer, - PAGE_ALIGN(io_tlb_overflow)); memblock_free_late(__pa(io_tlb_orig_addr), PAGE_ALIGN(io_tlb_nslabs * sizeof(phys_addr_t))); memblock_free_late(__pa(io_tlb_list), @@ -429,7 +383,7 @@ void __init swiotlb_exit(void) max_segment = 0; } -int is_swiotlb_buffer(phys_addr_t paddr) +static int is_swiotlb_buffer(phys_addr_t paddr) { return paddr >= io_tlb_start && paddr < io_tlb_end; } @@ -591,26 +545,6 @@ found: } /* - * Allocates bounce buffer and returns its physical address. - */ -static phys_addr_t -map_single(struct device *hwdev, phys_addr_t phys, size_t size, - enum dma_data_direction dir, unsigned long attrs) -{ - dma_addr_t start_dma_addr; - - if (swiotlb_force == SWIOTLB_NO_FORCE) { - dev_warn_ratelimited(hwdev, "Cannot do DMA to address %pa\n", - &phys); - return SWIOTLB_MAP_ERROR; - } - - start_dma_addr = __phys_to_dma(hwdev, io_tlb_start); - return swiotlb_tbl_map_single(hwdev, start_dma_addr, phys, size, - dir, attrs); -} - -/* * tlb_addr is the physical address of the bounce buffer to unmap. */ void swiotlb_tbl_unmap_single(struct device *hwdev, phys_addr_t tlb_addr, @@ -689,104 +623,32 @@ void swiotlb_tbl_sync_single(struct device *hwdev, phys_addr_t tlb_addr, } } -static inline bool dma_coherent_ok(struct device *dev, dma_addr_t addr, - size_t size) -{ - u64 mask = DMA_BIT_MASK(32); - - if (dev && dev->coherent_dma_mask) - mask = dev->coherent_dma_mask; - return addr + size - 1 <= mask; -} - -static void * -swiotlb_alloc_buffer(struct device *dev, size_t size, dma_addr_t *dma_handle, - unsigned long attrs) +static dma_addr_t swiotlb_bounce_page(struct device *dev, phys_addr_t *phys, + size_t size, enum dma_data_direction dir, unsigned long attrs) { - phys_addr_t phys_addr; - - if (swiotlb_force == SWIOTLB_NO_FORCE) - goto out_warn; - - phys_addr = swiotlb_tbl_map_single(dev, - __phys_to_dma(dev, io_tlb_start), - 0, size, DMA_FROM_DEVICE, attrs); - if (phys_addr == SWIOTLB_MAP_ERROR) - goto out_warn; - - *dma_handle = __phys_to_dma(dev, phys_addr); - if (!dma_coherent_ok(dev, *dma_handle, size)) - goto out_unmap; - - memset(phys_to_virt(phys_addr), 0, size); - return phys_to_virt(phys_addr); + dma_addr_t dma_addr; -out_unmap: - dev_warn(dev, "hwdev DMA mask = 0x%016Lx, dev_addr = 0x%016Lx\n", - (unsigned long long)dev->coherent_dma_mask, - (unsigned long long)*dma_handle); - - /* - * DMA_TO_DEVICE to avoid memcpy in unmap_single. - * DMA_ATTR_SKIP_CPU_SYNC is optional. - */ - swiotlb_tbl_unmap_single(dev, phys_addr, size, DMA_TO_DEVICE, - DMA_ATTR_SKIP_CPU_SYNC); -out_warn: - if (!(attrs & DMA_ATTR_NO_WARN) && printk_ratelimit()) { - dev_warn(dev, - "swiotlb: coherent allocation failed, size=%zu\n", - size); - dump_stack(); + if (unlikely(swiotlb_force == SWIOTLB_NO_FORCE)) { + dev_warn_ratelimited(dev, + "Cannot do DMA to address %pa\n", phys); + return DIRECT_MAPPING_ERROR; } - return NULL; -} - -static bool swiotlb_free_buffer(struct device *dev, size_t size, - dma_addr_t dma_addr) -{ - phys_addr_t phys_addr = dma_to_phys(dev, dma_addr); - WARN_ON_ONCE(irqs_disabled()); - - if (!is_swiotlb_buffer(phys_addr)) - return false; - - /* - * DMA_TO_DEVICE to avoid memcpy in swiotlb_tbl_unmap_single. - * DMA_ATTR_SKIP_CPU_SYNC is optional. - */ - swiotlb_tbl_unmap_single(dev, phys_addr, size, DMA_TO_DEVICE, - DMA_ATTR_SKIP_CPU_SYNC); - return true; -} - -static void -swiotlb_full(struct device *dev, size_t size, enum dma_data_direction dir, - int do_panic) -{ - if (swiotlb_force == SWIOTLB_NO_FORCE) - return; - - /* - * Ran out of IOMMU space for this operation. This is very bad. - * Unfortunately the drivers cannot handle this operation properly. - * unless they check for dma_mapping_error (most don't) - * When the mapping is small enough return a static buffer to limit - * the damage, or panic when the transfer is too big. - */ - dev_err_ratelimited(dev, "DMA: Out of SW-IOMMU space for %zu bytes\n", - size); + /* 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 == SWIOTLB_MAP_ERROR) + return DIRECT_MAPPING_ERROR; - if (size <= io_tlb_overflow || !do_panic) - return; + /* Ensure that the address returned is DMA'ble */ + 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 DIRECT_MAPPING_ERROR; + } - if (dir == DMA_BIDIRECTIONAL) - panic("DMA: Random memory could be DMA accessed\n"); - if (dir == DMA_FROM_DEVICE) - panic("DMA: Random memory could be DMA written\n"); - if (dir == DMA_TO_DEVICE) - panic("DMA: Random memory could be DMA read\n"); + return dma_addr; } /* @@ -801,7 +663,7 @@ dma_addr_t swiotlb_map_page(struct device *dev, struct page *page, enum dma_data_direction dir, unsigned long attrs) { - phys_addr_t map, phys = page_to_phys(page) + offset; + phys_addr_t phys = page_to_phys(page) + offset; dma_addr_t dev_addr = phys_to_dma(dev, phys); BUG_ON(dir == DMA_NONE); @@ -810,28 +672,17 @@ dma_addr_t swiotlb_map_page(struct device *dev, struct page *page, * 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) - return dev_addr; - - trace_swiotlb_bounced(dev, dev_addr, size, swiotlb_force); - - /* Oh well, have to allocate and map a bounce buffer. */ - map = map_single(dev, phys, size, dir, attrs); - if (map == SWIOTLB_MAP_ERROR) { - swiotlb_full(dev, size, dir, 1); - return __phys_to_dma(dev, io_tlb_overflow_buffer); + 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); } - dev_addr = __phys_to_dma(dev, map); + if (!dev_is_dma_coherent(dev) && + (attrs & DMA_ATTR_SKIP_CPU_SYNC) == 0) + arch_sync_dma_for_device(dev, phys, size, dir); - /* Ensure that the address returned is DMA'ble */ - if (dma_capable(dev, dev_addr, size)) - return dev_addr; - - attrs |= DMA_ATTR_SKIP_CPU_SYNC; - swiotlb_tbl_unmap_single(dev, map, size, dir, attrs); - - return __phys_to_dma(dev, io_tlb_overflow_buffer); + return dev_addr; } /* @@ -842,14 +693,18 @@ dma_addr_t swiotlb_map_page(struct device *dev, struct page *page, * After this call, reads by the cpu to the buffer are guaranteed to see * whatever the device wrote there. */ -static void unmap_single(struct device *hwdev, dma_addr_t dev_addr, - size_t size, enum dma_data_direction dir, - unsigned long attrs) +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); return; @@ -867,13 +722,6 @@ static void unmap_single(struct device *hwdev, dma_addr_t dev_addr, dma_mark_clean(phys_to_virt(paddr), size); } -void swiotlb_unmap_page(struct device *hwdev, dma_addr_t dev_addr, - size_t size, enum dma_data_direction dir, - unsigned long attrs) -{ - unmap_single(hwdev, dev_addr, size, dir, attrs); -} - /* * Make physical memory consistent for a single streaming mode DMA translation * after a transfer. @@ -893,15 +741,17 @@ swiotlb_sync_single(struct device *hwdev, dma_addr_t dev_addr, BUG_ON(dir == DMA_NONE); - if (is_swiotlb_buffer(paddr)) { + 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); - return; - } - if (dir != DMA_FROM_DEVICE) - return; + if (!dev_is_dma_coherent(hwdev) && target == SYNC_FOR_DEVICE) + arch_sync_dma_for_device(hwdev, paddr, size, dir); - dma_mark_clean(phys_to_virt(paddr), size); + if (!is_swiotlb_buffer(paddr) && dir == DMA_FROM_DEVICE) + dma_mark_clean(phys_to_virt(paddr), size); } void @@ -925,48 +775,31 @@ swiotlb_sync_single_for_device(struct device *hwdev, dma_addr_t dev_addr, * appropriate dma address and length. They are obtained via * sg_dma_{address,length}(SG). * - * NOTE: An implementation may be able to use a smaller number of - * DMA address/length pairs than there are SG table elements. - * (for example via virtual mapping capabilities) - * The routine returns the number of addr/length pairs actually - * used, at most nents. - * * Device ownership issues as mentioned above for swiotlb_map_page are the * same here. */ int -swiotlb_map_sg_attrs(struct device *hwdev, struct scatterlist *sgl, int nelems, +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; - BUG_ON(dir == DMA_NONE); - for_each_sg(sgl, sg, nelems, i) { - phys_addr_t paddr = sg_phys(sg); - dma_addr_t dev_addr = phys_to_dma(hwdev, paddr); - - if (swiotlb_force == SWIOTLB_FORCE || - !dma_capable(hwdev, dev_addr, sg->length)) { - phys_addr_t map = map_single(hwdev, sg_phys(sg), - sg->length, dir, attrs); - if (map == SWIOTLB_MAP_ERROR) { - /* Don't panic here, we expect map_sg users - to do proper error handling. */ - swiotlb_full(hwdev, sg->length, dir, 0); - attrs |= DMA_ATTR_SKIP_CPU_SYNC; - swiotlb_unmap_sg_attrs(hwdev, sgl, i, dir, - attrs); - sg_dma_len(sgl) = 0; - return 0; - } - sg->dma_address = __phys_to_dma(hwdev, map); - } else - sg->dma_address = dev_addr; + sg->dma_address = swiotlb_map_page(dev, sg_page(sg), sg->offset, + sg->length, dir, attrs); + if (sg->dma_address == DIRECT_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; } /* @@ -984,7 +817,7 @@ swiotlb_unmap_sg_attrs(struct device *hwdev, struct scatterlist *sgl, BUG_ON(dir == DMA_NONE); for_each_sg(sgl, sg, nelems, i) - unmap_single(hwdev, sg->dma_address, sg_dma_len(sg), dir, + swiotlb_unmap_page(hwdev, sg->dma_address, sg_dma_len(sg), dir, attrs); } @@ -1022,12 +855,6 @@ swiotlb_sync_sg_for_device(struct device *hwdev, struct scatterlist *sg, swiotlb_sync_sg(hwdev, sg, nelems, dir, SYNC_FOR_DEVICE); } -int -swiotlb_dma_mapping_error(struct device *hwdev, dma_addr_t dma_addr) -{ - return (dma_addr == __phys_to_dma(hwdev, io_tlb_overflow_buffer)); -} - /* * Return whether the given device DMA address mask can be supported * properly. For example, if your device can only drive the low 24-bits @@ -1040,39 +867,10 @@ swiotlb_dma_supported(struct device *hwdev, u64 mask) return __phys_to_dma(hwdev, io_tlb_end - 1) <= mask; } -void *swiotlb_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle, - gfp_t gfp, unsigned long attrs) -{ - void *vaddr; - - /* temporary workaround: */ - if (gfp & __GFP_NOWARN) - attrs |= DMA_ATTR_NO_WARN; - - /* - * Don't print a warning when the first allocation attempt fails. - * swiotlb_alloc_coherent() will print a warning when the DMA memory - * allocation ultimately failed. - */ - gfp |= __GFP_NOWARN; - - vaddr = dma_direct_alloc(dev, size, dma_handle, gfp, attrs); - if (!vaddr) - vaddr = swiotlb_alloc_buffer(dev, size, dma_handle, attrs); - return vaddr; -} - -void swiotlb_free(struct device *dev, size_t size, void *vaddr, - dma_addr_t dma_addr, unsigned long attrs) -{ - if (!swiotlb_free_buffer(dev, size, dma_addr)) - dma_direct_free(dev, size, vaddr, dma_addr, attrs); -} - const struct dma_map_ops swiotlb_dma_ops = { - .mapping_error = swiotlb_dma_mapping_error, - .alloc = swiotlb_alloc, - .free = swiotlb_free, + .mapping_error = dma_direct_mapping_error, + .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, |