| #include <linux/dma-mapping.h> |
| #include <linux/dma-debug.h> |
| #include <linux/dmar.h> |
| #include <linux/bootmem.h> |
| #include <linux/pci.h> |
| #include <linux/kmemleak.h> |
| |
| #include <asm/proto.h> |
| #include <asm/dma.h> |
| #include <asm/iommu.h> |
| #include <asm/gart.h> |
| #include <asm/calgary.h> |
| #include <asm/amd_iommu.h> |
| |
| static int forbid_dac __read_mostly; |
| |
| struct dma_map_ops *dma_ops; |
| EXPORT_SYMBOL(dma_ops); |
| |
| static int iommu_sac_force __read_mostly; |
| |
| #ifdef CONFIG_IOMMU_DEBUG |
| int panic_on_overflow __read_mostly = 1; |
| int force_iommu __read_mostly = 1; |
| #else |
| int panic_on_overflow __read_mostly = 0; |
| int force_iommu __read_mostly = 0; |
| #endif |
| |
| int iommu_merge __read_mostly = 0; |
| |
| int no_iommu __read_mostly; |
| /* Set this to 1 if there is a HW IOMMU in the system */ |
| int iommu_detected __read_mostly = 0; |
| |
| /* |
| * This variable becomes 1 if iommu=pt is passed on the kernel command line. |
| * If this variable is 1, IOMMU implementations do no DMA translation for |
| * devices and allow every device to access to whole physical memory. This is |
| * useful if a user want to use an IOMMU only for KVM device assignment to |
| * guests and not for driver dma translation. |
| */ |
| int iommu_pass_through __read_mostly; |
| |
| dma_addr_t bad_dma_address __read_mostly = 0; |
| EXPORT_SYMBOL(bad_dma_address); |
| |
| /* Dummy device used for NULL arguments (normally ISA). Better would |
| be probably a smaller DMA mask, but this is bug-to-bug compatible |
| to older i386. */ |
| struct device x86_dma_fallback_dev = { |
| .init_name = "fallback device", |
| .coherent_dma_mask = DMA_BIT_MASK(32), |
| .dma_mask = &x86_dma_fallback_dev.coherent_dma_mask, |
| }; |
| EXPORT_SYMBOL(x86_dma_fallback_dev); |
| |
| /* Number of entries preallocated for DMA-API debugging */ |
| #define PREALLOC_DMA_DEBUG_ENTRIES 32768 |
| |
| int dma_set_mask(struct device *dev, u64 mask) |
| { |
| if (!dev->dma_mask || !dma_supported(dev, mask)) |
| return -EIO; |
| |
| *dev->dma_mask = mask; |
| |
| return 0; |
| } |
| EXPORT_SYMBOL(dma_set_mask); |
| |
| #ifdef CONFIG_X86_64 |
| static __initdata void *dma32_bootmem_ptr; |
| static unsigned long dma32_bootmem_size __initdata = (128ULL<<20); |
| |
| static int __init parse_dma32_size_opt(char *p) |
| { |
| if (!p) |
| return -EINVAL; |
| dma32_bootmem_size = memparse(p, &p); |
| return 0; |
| } |
| early_param("dma32_size", parse_dma32_size_opt); |
| |
| void __init dma32_reserve_bootmem(void) |
| { |
| unsigned long size, align; |
| if (max_pfn <= MAX_DMA32_PFN) |
| return; |
| |
| /* |
| * check aperture_64.c allocate_aperture() for reason about |
| * using 512M as goal |
| */ |
| align = 64ULL<<20; |
| size = roundup(dma32_bootmem_size, align); |
| dma32_bootmem_ptr = __alloc_bootmem_nopanic(size, align, |
| 512ULL<<20); |
| /* |
| * Kmemleak should not scan this block as it may not be mapped via the |
| * kernel direct mapping. |
| */ |
| kmemleak_ignore(dma32_bootmem_ptr); |
| if (dma32_bootmem_ptr) |
| dma32_bootmem_size = size; |
| else |
| dma32_bootmem_size = 0; |
| } |
| static void __init dma32_free_bootmem(void) |
| { |
| |
| if (max_pfn <= MAX_DMA32_PFN) |
| return; |
| |
| if (!dma32_bootmem_ptr) |
| return; |
| |
| free_bootmem(__pa(dma32_bootmem_ptr), dma32_bootmem_size); |
| |
| dma32_bootmem_ptr = NULL; |
| dma32_bootmem_size = 0; |
| } |
| #endif |
| |
| void __init pci_iommu_alloc(void) |
| { |
| #ifdef CONFIG_X86_64 |
| /* free the range so iommu could get some range less than 4G */ |
| dma32_free_bootmem(); |
| #endif |
| |
| /* |
| * The order of these functions is important for |
| * fall-back/fail-over reasons |
| */ |
| gart_iommu_hole_init(); |
| |
| detect_calgary(); |
| |
| detect_intel_iommu(); |
| |
| amd_iommu_detect(); |
| |
| pci_swiotlb_init(); |
| } |
| |
| void *dma_generic_alloc_coherent(struct device *dev, size_t size, |
| dma_addr_t *dma_addr, gfp_t flag) |
| { |
| unsigned long dma_mask; |
| struct page *page; |
| dma_addr_t addr; |
| |
| dma_mask = dma_alloc_coherent_mask(dev, flag); |
| |
| flag |= __GFP_ZERO; |
| again: |
| page = alloc_pages_node(dev_to_node(dev), flag, get_order(size)); |
| if (!page) |
| return NULL; |
| |
| addr = page_to_phys(page); |
| if (addr + size > dma_mask) { |
| __free_pages(page, get_order(size)); |
| |
| if (dma_mask < DMA_BIT_MASK(32) && !(flag & GFP_DMA)) { |
| flag = (flag & ~GFP_DMA32) | GFP_DMA; |
| goto again; |
| } |
| |
| return NULL; |
| } |
| |
| *dma_addr = addr; |
| return page_address(page); |
| } |
| |
| /* |
| * See <Documentation/x86_64/boot-options.txt> for the iommu kernel parameter |
| * documentation. |
| */ |
| static __init int iommu_setup(char *p) |
| { |
| iommu_merge = 1; |
| |
| if (!p) |
| return -EINVAL; |
| |
| while (*p) { |
| if (!strncmp(p, "off", 3)) |
| no_iommu = 1; |
| /* gart_parse_options has more force support */ |
| if (!strncmp(p, "force", 5)) |
| force_iommu = 1; |
| if (!strncmp(p, "noforce", 7)) { |
| iommu_merge = 0; |
| force_iommu = 0; |
| } |
| |
| if (!strncmp(p, "biomerge", 8)) { |
| iommu_merge = 1; |
| force_iommu = 1; |
| } |
| if (!strncmp(p, "panic", 5)) |
| panic_on_overflow = 1; |
| if (!strncmp(p, "nopanic", 7)) |
| panic_on_overflow = 0; |
| if (!strncmp(p, "merge", 5)) { |
| iommu_merge = 1; |
| force_iommu = 1; |
| } |
| if (!strncmp(p, "nomerge", 7)) |
| iommu_merge = 0; |
| if (!strncmp(p, "forcesac", 8)) |
| iommu_sac_force = 1; |
| if (!strncmp(p, "allowdac", 8)) |
| forbid_dac = 0; |
| if (!strncmp(p, "nodac", 5)) |
| forbid_dac = -1; |
| if (!strncmp(p, "usedac", 6)) { |
| forbid_dac = -1; |
| return 1; |
| } |
| #ifdef CONFIG_SWIOTLB |
| if (!strncmp(p, "soft", 4)) |
| swiotlb = 1; |
| #endif |
| if (!strncmp(p, "pt", 2)) |
| iommu_pass_through = 1; |
| |
| gart_parse_options(p); |
| |
| #ifdef CONFIG_CALGARY_IOMMU |
| if (!strncmp(p, "calgary", 7)) |
| use_calgary = 1; |
| #endif /* CONFIG_CALGARY_IOMMU */ |
| |
| p += strcspn(p, ","); |
| if (*p == ',') |
| ++p; |
| } |
| return 0; |
| } |
| early_param("iommu", iommu_setup); |
| |
| int dma_supported(struct device *dev, u64 mask) |
| { |
| struct dma_map_ops *ops = get_dma_ops(dev); |
| |
| #ifdef CONFIG_PCI |
| if (mask > 0xffffffff && forbid_dac > 0) { |
| dev_info(dev, "PCI: Disallowing DAC for device\n"); |
| return 0; |
| } |
| #endif |
| |
| if (ops->dma_supported) |
| return ops->dma_supported(dev, mask); |
| |
| /* Copied from i386. Doesn't make much sense, because it will |
| only work for pci_alloc_coherent. |
| The caller just has to use GFP_DMA in this case. */ |
| if (mask < DMA_BIT_MASK(24)) |
| return 0; |
| |
| /* Tell the device to use SAC when IOMMU force is on. This |
| allows the driver to use cheaper accesses in some cases. |
| |
| Problem with this is that if we overflow the IOMMU area and |
| return DAC as fallback address the device may not handle it |
| correctly. |
| |
| As a special case some controllers have a 39bit address |
| mode that is as efficient as 32bit (aic79xx). Don't force |
| SAC for these. Assume all masks <= 40 bits are of this |
| type. Normally this doesn't make any difference, but gives |
| more gentle handling of IOMMU overflow. */ |
| if (iommu_sac_force && (mask >= DMA_BIT_MASK(40))) { |
| dev_info(dev, "Force SAC with mask %Lx\n", mask); |
| return 0; |
| } |
| |
| return 1; |
| } |
| EXPORT_SYMBOL(dma_supported); |
| |
| static int __init pci_iommu_init(void) |
| { |
| dma_debug_init(PREALLOC_DMA_DEBUG_ENTRIES); |
| |
| #ifdef CONFIG_PCI |
| dma_debug_add_bus(&pci_bus_type); |
| #endif |
| |
| calgary_iommu_init(); |
| |
| intel_iommu_init(); |
| |
| amd_iommu_init(); |
| |
| gart_iommu_init(); |
| |
| no_iommu_init(); |
| return 0; |
| } |
| |
| void pci_iommu_shutdown(void) |
| { |
| gart_iommu_shutdown(); |
| |
| amd_iommu_shutdown(); |
| } |
| /* Must execute after PCI subsystem */ |
| rootfs_initcall(pci_iommu_init); |
| |
| #ifdef CONFIG_PCI |
| /* Many VIA bridges seem to corrupt data for DAC. Disable it here */ |
| |
| static __devinit void via_no_dac(struct pci_dev *dev) |
| { |
| if ((dev->class >> 8) == PCI_CLASS_BRIDGE_PCI && forbid_dac == 0) { |
| dev_info(&dev->dev, "disabling DAC on VIA PCI bridge\n"); |
| forbid_dac = 1; |
| } |
| } |
| DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_VIA, PCI_ANY_ID, via_no_dac); |
| #endif |