diff options
Diffstat (limited to 'drivers/xen/swiotlb-xen.c')
-rw-r--r-- | drivers/xen/swiotlb-xen.c | 362 |
1 files changed, 107 insertions, 255 deletions
diff --git a/drivers/xen/swiotlb-xen.c b/drivers/xen/swiotlb-xen.c index b6d27762c6f8..67aa74d20162 100644 --- a/drivers/xen/swiotlb-xen.c +++ b/drivers/xen/swiotlb-xen.c @@ -28,7 +28,7 @@ #include <linux/memblock.h> #include <linux/dma-direct.h> -#include <linux/dma-noncoherent.h> +#include <linux/dma-map-ops.h> #include <linux/export.h> #include <xen/swiotlb-xen.h> #include <xen/page.h> @@ -36,53 +36,42 @@ #include <xen/hvc-console.h> #include <asm/dma-mapping.h> -#include <asm/xen/page-coherent.h> #include <trace/events/swiotlb.h> #define MAX_DMA_BITS 32 -/* - * Used to do a quick range check in swiotlb_tbl_unmap_single and - * swiotlb_tbl_sync_single_*, to see if the memory was in fact allocated by this - * API. - */ -static char *xen_io_tlb_start, *xen_io_tlb_end; -static unsigned long xen_io_tlb_nslabs; /* * Quick lookup value of the bus address of the IOTLB. */ -static u64 start_dma_addr; - -/* - * Both of these functions should avoid XEN_PFN_PHYS because phys_addr_t - * can be 32bit when dma_addr_t is 64bit leading to a loss in - * information if the shift is done before casting to 64bit. - */ -static inline dma_addr_t xen_phys_to_bus(phys_addr_t paddr) +static inline phys_addr_t xen_phys_to_bus(struct device *dev, phys_addr_t paddr) { unsigned long bfn = pfn_to_bfn(XEN_PFN_DOWN(paddr)); - dma_addr_t dma = (dma_addr_t)bfn << XEN_PAGE_SHIFT; + phys_addr_t baddr = (phys_addr_t)bfn << XEN_PAGE_SHIFT; - dma |= paddr & ~XEN_PAGE_MASK; + baddr |= paddr & ~XEN_PAGE_MASK; + return baddr; +} - return dma; +static inline dma_addr_t xen_phys_to_dma(struct device *dev, phys_addr_t paddr) +{ + return phys_to_dma(dev, xen_phys_to_bus(dev, paddr)); } -static inline phys_addr_t xen_bus_to_phys(dma_addr_t baddr) +static inline phys_addr_t xen_bus_to_phys(struct device *dev, + phys_addr_t baddr) { unsigned long xen_pfn = bfn_to_pfn(XEN_PFN_DOWN(baddr)); - dma_addr_t dma = (dma_addr_t)xen_pfn << XEN_PAGE_SHIFT; - phys_addr_t paddr = dma; - - paddr |= baddr & ~XEN_PAGE_MASK; + phys_addr_t paddr = (xen_pfn << XEN_PAGE_SHIFT) | + (baddr & ~XEN_PAGE_MASK); return paddr; } -static inline dma_addr_t xen_virt_to_bus(void *address) +static inline phys_addr_t xen_dma_to_phys(struct device *dev, + dma_addr_t dma_addr) { - return xen_phys_to_bus(virt_to_phys(address)); + return xen_bus_to_phys(dev, dma_to_phys(dev, dma_addr)); } static inline int range_straddles_page_boundary(phys_addr_t p, size_t size) @@ -99,260 +88,101 @@ static inline int range_straddles_page_boundary(phys_addr_t p, size_t size) return 0; } -static int is_xen_swiotlb_buffer(dma_addr_t dma_addr) +static int is_xen_swiotlb_buffer(struct device *dev, dma_addr_t dma_addr) { - unsigned long bfn = XEN_PFN_DOWN(dma_addr); + unsigned long bfn = XEN_PFN_DOWN(dma_to_phys(dev, dma_addr)); unsigned long xen_pfn = bfn_to_local_pfn(bfn); - phys_addr_t paddr = XEN_PFN_PHYS(xen_pfn); + phys_addr_t paddr = (phys_addr_t)xen_pfn << XEN_PAGE_SHIFT; /* If the address is outside our domain, it CAN * have the same virtual address as another address * in our domain. Therefore _only_ check address within our domain. */ - if (pfn_valid(PFN_DOWN(paddr))) { - return paddr >= virt_to_phys(xen_io_tlb_start) && - paddr < virt_to_phys(xen_io_tlb_end); - } + if (pfn_valid(PFN_DOWN(paddr))) + return is_swiotlb_buffer(dev, paddr); return 0; } -static int -xen_swiotlb_fixup(void *buf, size_t size, unsigned long nslabs) +#ifdef CONFIG_X86 +int xen_swiotlb_fixup(void *buf, unsigned long nslabs) { - int i, rc; - int dma_bits; + int rc; + unsigned int order = get_order(IO_TLB_SEGSIZE << IO_TLB_SHIFT); + unsigned int i, dma_bits = order + PAGE_SHIFT; dma_addr_t dma_handle; phys_addr_t p = virt_to_phys(buf); - dma_bits = get_order(IO_TLB_SEGSIZE << IO_TLB_SHIFT) + PAGE_SHIFT; + BUILD_BUG_ON(IO_TLB_SEGSIZE & (IO_TLB_SEGSIZE - 1)); + BUG_ON(nslabs % IO_TLB_SEGSIZE); i = 0; do { - int slabs = min(nslabs - i, (unsigned long)IO_TLB_SEGSIZE); - do { rc = xen_create_contiguous_region( - p + (i << IO_TLB_SHIFT), - get_order(slabs << IO_TLB_SHIFT), + p + (i << IO_TLB_SHIFT), order, dma_bits, &dma_handle); } while (rc && dma_bits++ < MAX_DMA_BITS); if (rc) return rc; - i += slabs; + i += IO_TLB_SEGSIZE; } while (i < nslabs); return 0; } -static unsigned long xen_set_nslabs(unsigned long nr_tbl) -{ - if (!nr_tbl) { - xen_io_tlb_nslabs = (64 * 1024 * 1024 >> IO_TLB_SHIFT); - xen_io_tlb_nslabs = ALIGN(xen_io_tlb_nslabs, IO_TLB_SEGSIZE); - } else - xen_io_tlb_nslabs = nr_tbl; - - return xen_io_tlb_nslabs << IO_TLB_SHIFT; -} - -enum xen_swiotlb_err { - XEN_SWIOTLB_UNKNOWN = 0, - XEN_SWIOTLB_ENOMEM, - XEN_SWIOTLB_EFIXUP -}; - -static const char *xen_swiotlb_error(enum xen_swiotlb_err err) -{ - switch (err) { - case XEN_SWIOTLB_ENOMEM: - return "Cannot allocate Xen-SWIOTLB buffer\n"; - case XEN_SWIOTLB_EFIXUP: - return "Failed to get contiguous memory for DMA from Xen!\n"\ - "You either: don't have the permissions, do not have"\ - " enough free memory under 4GB, or the hypervisor memory"\ - " is too fragmented!"; - default: - break; - } - return ""; -} -int __ref xen_swiotlb_init(int verbose, bool early) -{ - unsigned long bytes, order; - int rc = -ENOMEM; - enum xen_swiotlb_err m_ret = XEN_SWIOTLB_UNKNOWN; - unsigned int repeat = 3; - - xen_io_tlb_nslabs = swiotlb_nr_tbl(); -retry: - bytes = xen_set_nslabs(xen_io_tlb_nslabs); - order = get_order(xen_io_tlb_nslabs << IO_TLB_SHIFT); - - /* - * IO TLB memory already allocated. Just use it. - */ - if (io_tlb_start != 0) { - xen_io_tlb_start = phys_to_virt(io_tlb_start); - goto end; - } - - /* - * Get IO TLB memory from any location. - */ - if (early) { - xen_io_tlb_start = memblock_alloc(PAGE_ALIGN(bytes), - PAGE_SIZE); - if (!xen_io_tlb_start) - panic("%s: Failed to allocate %lu bytes align=0x%lx\n", - __func__, PAGE_ALIGN(bytes), PAGE_SIZE); - } else { -#define SLABS_PER_PAGE (1 << (PAGE_SHIFT - IO_TLB_SHIFT)) -#define IO_TLB_MIN_SLABS ((1<<20) >> IO_TLB_SHIFT) - while ((SLABS_PER_PAGE << order) > IO_TLB_MIN_SLABS) { - xen_io_tlb_start = (void *)xen_get_swiotlb_free_pages(order); - if (xen_io_tlb_start) - break; - order--; - } - if (order != get_order(bytes)) { - pr_warn("Warning: only able to allocate %ld MB for software IO TLB\n", - (PAGE_SIZE << order) >> 20); - xen_io_tlb_nslabs = SLABS_PER_PAGE << order; - bytes = xen_io_tlb_nslabs << IO_TLB_SHIFT; - } - } - if (!xen_io_tlb_start) { - m_ret = XEN_SWIOTLB_ENOMEM; - goto error; - } - /* - * And replace that memory with pages under 4GB. - */ - rc = xen_swiotlb_fixup(xen_io_tlb_start, - bytes, - xen_io_tlb_nslabs); - if (rc) { - if (early) - memblock_free(__pa(xen_io_tlb_start), - PAGE_ALIGN(bytes)); - else { - free_pages((unsigned long)xen_io_tlb_start, order); - xen_io_tlb_start = NULL; - } - m_ret = XEN_SWIOTLB_EFIXUP; - goto error; - } - start_dma_addr = xen_virt_to_bus(xen_io_tlb_start); - if (early) { - if (swiotlb_init_with_tbl(xen_io_tlb_start, xen_io_tlb_nslabs, - verbose)) - panic("Cannot allocate SWIOTLB buffer"); - rc = 0; - } else - rc = swiotlb_late_init_with_tbl(xen_io_tlb_start, xen_io_tlb_nslabs); - -end: - xen_io_tlb_end = xen_io_tlb_start + bytes; - if (!rc) - swiotlb_set_max_segment(PAGE_SIZE); - - return rc; -error: - if (repeat--) { - xen_io_tlb_nslabs = max(1024UL, /* Min is 2MB */ - (xen_io_tlb_nslabs >> 1)); - pr_info("Lowering to %luMB\n", - (xen_io_tlb_nslabs << IO_TLB_SHIFT) >> 20); - goto retry; - } - pr_err("%s (rc:%d)\n", xen_swiotlb_error(m_ret), rc); - if (early) - panic("%s (rc:%d)", xen_swiotlb_error(m_ret), rc); - else - free_pages((unsigned long)xen_io_tlb_start, order); - return rc; -} static void * -xen_swiotlb_alloc_coherent(struct device *hwdev, size_t size, - dma_addr_t *dma_handle, gfp_t flags, - unsigned long attrs) +xen_swiotlb_alloc_coherent(struct device *dev, size_t size, + dma_addr_t *dma_handle, gfp_t flags, unsigned long attrs) { - void *ret; + u64 dma_mask = dev->coherent_dma_mask; int order = get_order(size); - u64 dma_mask = DMA_BIT_MASK(32); phys_addr_t phys; - dma_addr_t dev_addr; - - /* - * Ignore region specifiers - the kernel's ideas of - * pseudo-phys memory layout has nothing to do with the - * machine physical layout. We can't allocate highmem - * because we can't return a pointer to it. - */ - flags &= ~(__GFP_DMA | __GFP_HIGHMEM); + void *ret; - /* Convert the size to actually allocated. */ + /* Align the allocation to the Xen page size */ size = 1UL << (order + XEN_PAGE_SHIFT); - /* On ARM this function returns an ioremap'ped virtual address for - * which virt_to_phys doesn't return the corresponding physical - * address. In fact on ARM virt_to_phys only works for kernel direct - * mapped RAM memory. Also see comment below. - */ - ret = xen_alloc_coherent_pages(hwdev, size, dma_handle, flags, attrs); - + ret = (void *)__get_free_pages(flags, get_order(size)); if (!ret) return ret; - - if (hwdev && hwdev->coherent_dma_mask) - dma_mask = hwdev->coherent_dma_mask; - - /* At this point dma_handle is the physical address, next we are - * going to set it to the machine address. - * Do not use virt_to_phys(ret) because on ARM it doesn't correspond - * to *dma_handle. */ - phys = *dma_handle; - dev_addr = xen_phys_to_bus(phys); - if (((dev_addr + size - 1 <= dma_mask)) && - !range_straddles_page_boundary(phys, size)) - *dma_handle = dev_addr; - else { - if (xen_create_contiguous_region(phys, order, - fls64(dma_mask), dma_handle) != 0) { - xen_free_coherent_pages(hwdev, size, ret, (dma_addr_t)phys, attrs); - return NULL; - } + phys = virt_to_phys(ret); + + *dma_handle = xen_phys_to_dma(dev, phys); + if (*dma_handle + size - 1 > dma_mask || + range_straddles_page_boundary(phys, size)) { + if (xen_create_contiguous_region(phys, order, fls64(dma_mask), + dma_handle) != 0) + goto out_free_pages; SetPageXenRemapped(virt_to_page(ret)); } + memset(ret, 0, size); return ret; + +out_free_pages: + free_pages((unsigned long)ret, get_order(size)); + return NULL; } static void -xen_swiotlb_free_coherent(struct device *hwdev, size_t size, void *vaddr, - dma_addr_t dev_addr, unsigned long attrs) +xen_swiotlb_free_coherent(struct device *dev, size_t size, void *vaddr, + dma_addr_t dma_handle, unsigned long attrs) { + phys_addr_t phys = virt_to_phys(vaddr); int order = get_order(size); - phys_addr_t phys; - u64 dma_mask = DMA_BIT_MASK(32); - - if (hwdev && hwdev->coherent_dma_mask) - dma_mask = hwdev->coherent_dma_mask; - - /* do not use virt_to_phys because on ARM it doesn't return you the - * physical address */ - phys = xen_bus_to_phys(dev_addr); /* Convert the size to actually allocated. */ size = 1UL << (order + XEN_PAGE_SHIFT); - if (!WARN_ON((dev_addr + size - 1 > dma_mask) || - range_straddles_page_boundary(phys, size)) && - TestClearPageXenRemapped(virt_to_page(vaddr))) - xen_destroy_contiguous_region(phys, order); + if (WARN_ON_ONCE(dma_handle + size - 1 > dev->coherent_dma_mask) || + WARN_ON_ONCE(range_straddles_page_boundary(phys, size))) + return; - xen_free_coherent_pages(hwdev, size, vaddr, (dma_addr_t)phys, attrs); + if (TestClearPageXenRemapped(virt_to_page(vaddr))) + xen_destroy_contiguous_region(phys, order); + free_pages((unsigned long)vaddr, get_order(size)); } +#endif /* CONFIG_X86 */ /* * Map a single buffer of the indicated size for DMA in streaming mode. The @@ -367,7 +197,7 @@ static dma_addr_t xen_swiotlb_map_page(struct device *dev, struct page *page, unsigned long attrs) { phys_addr_t map, phys = page_to_phys(page) + offset; - dma_addr_t dev_addr = xen_phys_to_bus(phys); + dma_addr_t dev_addr = xen_phys_to_dma(dev, phys); BUG_ON(dir == DMA_NONE); /* @@ -378,34 +208,37 @@ static dma_addr_t xen_swiotlb_map_page(struct device *dev, struct page *page, if (dma_capable(dev, dev_addr, size, true) && !range_straddles_page_boundary(phys, size) && !xen_arch_need_swiotlb(dev, phys, dev_addr) && - swiotlb_force != SWIOTLB_FORCE) + !is_swiotlb_force_bounce(dev)) goto done; /* * Oh well, have to allocate and map a bounce buffer. */ - trace_swiotlb_bounced(dev, dev_addr, size, swiotlb_force); + trace_swiotlb_bounced(dev, dev_addr, size); - map = swiotlb_tbl_map_single(dev, start_dma_addr, phys, - size, size, dir, attrs); + map = swiotlb_tbl_map_single(dev, phys, size, size, 0, dir, attrs); if (map == (phys_addr_t)DMA_MAPPING_ERROR) return DMA_MAPPING_ERROR; phys = map; - dev_addr = xen_phys_to_bus(map); + dev_addr = xen_phys_to_dma(dev, map); /* * Ensure that the address returned is DMA'ble */ if (unlikely(!dma_capable(dev, dev_addr, size, true))) { - swiotlb_tbl_unmap_single(dev, map, size, size, dir, + swiotlb_tbl_unmap_single(dev, map, size, dir, attrs | DMA_ATTR_SKIP_CPU_SYNC); return DMA_MAPPING_ERROR; } done: - if (!dev_is_dma_coherent(dev) && !(attrs & DMA_ATTR_SKIP_CPU_SYNC)) - xen_dma_sync_for_device(dev_addr, phys, size, dir); + if (!dev_is_dma_coherent(dev) && !(attrs & DMA_ATTR_SKIP_CPU_SYNC)) { + if (pfn_valid(PFN_DOWN(dma_to_phys(dev, dev_addr)))) + arch_sync_dma_for_device(phys, size, dir); + else + xen_dma_sync_for_device(dev, dev_addr, size, dir); + } return dev_addr; } @@ -420,42 +253,54 @@ done: static void xen_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 = xen_bus_to_phys(dev_addr); + phys_addr_t paddr = xen_dma_to_phys(hwdev, dev_addr); BUG_ON(dir == DMA_NONE); - if (!dev_is_dma_coherent(hwdev) && !(attrs & DMA_ATTR_SKIP_CPU_SYNC)) - xen_dma_sync_for_cpu(dev_addr, paddr, size, dir); + if (!dev_is_dma_coherent(hwdev) && !(attrs & DMA_ATTR_SKIP_CPU_SYNC)) { + if (pfn_valid(PFN_DOWN(dma_to_phys(hwdev, dev_addr)))) + arch_sync_dma_for_cpu(paddr, size, dir); + else + xen_dma_sync_for_cpu(hwdev, dev_addr, size, dir); + } /* NOTE: We use dev_addr here, not paddr! */ - if (is_xen_swiotlb_buffer(dev_addr)) - swiotlb_tbl_unmap_single(hwdev, paddr, size, size, dir, attrs); + if (is_xen_swiotlb_buffer(hwdev, dev_addr)) + swiotlb_tbl_unmap_single(hwdev, paddr, size, dir, attrs); } static void xen_swiotlb_sync_single_for_cpu(struct device *dev, dma_addr_t dma_addr, size_t size, enum dma_data_direction dir) { - phys_addr_t paddr = xen_bus_to_phys(dma_addr); + phys_addr_t paddr = xen_dma_to_phys(dev, dma_addr); - if (!dev_is_dma_coherent(dev)) - xen_dma_sync_for_cpu(dma_addr, paddr, size, dir); + if (!dev_is_dma_coherent(dev)) { + if (pfn_valid(PFN_DOWN(dma_to_phys(dev, dma_addr)))) + arch_sync_dma_for_cpu(paddr, size, dir); + else + xen_dma_sync_for_cpu(dev, dma_addr, size, dir); + } - if (is_xen_swiotlb_buffer(dma_addr)) - swiotlb_tbl_sync_single(dev, paddr, size, dir, SYNC_FOR_CPU); + if (is_xen_swiotlb_buffer(dev, dma_addr)) + swiotlb_sync_single_for_cpu(dev, paddr, size, dir); } static void xen_swiotlb_sync_single_for_device(struct device *dev, dma_addr_t dma_addr, size_t size, enum dma_data_direction dir) { - phys_addr_t paddr = xen_bus_to_phys(dma_addr); + phys_addr_t paddr = xen_dma_to_phys(dev, dma_addr); - if (is_xen_swiotlb_buffer(dma_addr)) - swiotlb_tbl_sync_single(dev, paddr, size, dir, SYNC_FOR_DEVICE); + if (is_xen_swiotlb_buffer(dev, dma_addr)) + swiotlb_sync_single_for_device(dev, paddr, size, dir); - if (!dev_is_dma_coherent(dev)) - xen_dma_sync_for_device(dma_addr, paddr, size, dir); + if (!dev_is_dma_coherent(dev)) { + if (pfn_valid(PFN_DOWN(dma_to_phys(dev, dma_addr)))) + arch_sync_dma_for_device(paddr, size, dir); + else + xen_dma_sync_for_device(dev, dma_addr, size, dir); + } } /* @@ -498,7 +343,7 @@ xen_swiotlb_map_sg(struct device *dev, struct scatterlist *sgl, int nelems, out_unmap: xen_swiotlb_unmap_sg(dev, sgl, i, dir, attrs | DMA_ATTR_SKIP_CPU_SYNC); sg_dma_len(sgl) = 0; - return 0; + return -EIO; } static void @@ -536,12 +381,17 @@ xen_swiotlb_sync_sg_for_device(struct device *dev, struct scatterlist *sgl, static int xen_swiotlb_dma_supported(struct device *hwdev, u64 mask) { - return xen_virt_to_bus(xen_io_tlb_end - 1) <= mask; + return xen_phys_to_dma(hwdev, io_tlb_default_mem.end - 1) <= mask; } const struct dma_map_ops xen_swiotlb_dma_ops = { +#ifdef CONFIG_X86 .alloc = xen_swiotlb_alloc_coherent, .free = xen_swiotlb_free_coherent, +#else + .alloc = dma_direct_alloc, + .free = dma_direct_free, +#endif .sync_single_for_cpu = xen_swiotlb_sync_single_for_cpu, .sync_single_for_device = xen_swiotlb_sync_single_for_device, .sync_sg_for_cpu = xen_swiotlb_sync_sg_for_cpu, @@ -553,4 +403,6 @@ const struct dma_map_ops xen_swiotlb_dma_ops = { .dma_supported = xen_swiotlb_dma_supported, .mmap = dma_common_mmap, .get_sgtable = dma_common_get_sgtable, + .alloc_pages = dma_common_alloc_pages, + .free_pages = dma_common_free_pages, }; |