diff options
Diffstat (limited to 'arch/x86/kernel/pci-dma.c')
| -rw-r--r-- | arch/x86/kernel/pci-dma.c | 29 |
1 files changed, 19 insertions, 10 deletions
diff --git a/arch/x86/kernel/pci-dma.c b/arch/x86/kernel/pci-dma.c index 1a041bcf506..a6e804d16c3 100644 --- a/arch/x86/kernel/pci-dma.c +++ b/arch/x86/kernel/pci-dma.c @@ -3,6 +3,7 @@ #include <linux/dmar.h> #include <linux/bootmem.h> #include <linux/pci.h> +#include <linux/kmemleak.h> #include <asm/proto.h> #include <asm/dma.h> @@ -32,17 +33,22 @@ int no_iommu __read_mostly; /* Set this to 1 if there is a HW IOMMU in the system */ int iommu_detected __read_mostly = 0; -int iommu_pass_through; +/* + * 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. */ +/* Dummy device used for NULL arguments (normally ISA). */ struct device x86_dma_fallback_dev = { .init_name = "fallback device", - .coherent_dma_mask = DMA_BIT_MASK(32), + .coherent_dma_mask = ISA_DMA_BIT_MASK, .dma_mask = &x86_dma_fallback_dev.coherent_dma_mask, }; EXPORT_SYMBOL(x86_dma_fallback_dev); @@ -88,6 +94,11 @@ void __init dma32_reserve_bootmem(void) 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 @@ -147,7 +158,7 @@ again: return NULL; addr = page_to_phys(page); - if (!is_buffer_dma_capable(dma_mask, addr, size)) { + if (addr + size > dma_mask) { __free_pages(page, get_order(size)); if (dma_mask < DMA_BIT_MASK(32) && !(flag & GFP_DMA)) { @@ -212,10 +223,8 @@ static __init int iommu_setup(char *p) if (!strncmp(p, "soft", 4)) swiotlb = 1; #endif - if (!strncmp(p, "pt", 2)) { + if (!strncmp(p, "pt", 2)) iommu_pass_through = 1; - return 1; - } gart_parse_options(p); @@ -300,7 +309,7 @@ void pci_iommu_shutdown(void) amd_iommu_shutdown(); } /* Must execute after PCI subsystem */ -fs_initcall(pci_iommu_init); +rootfs_initcall(pci_iommu_init); #ifdef CONFIG_PCI /* Many VIA bridges seem to corrupt data for DAC. Disable it here */ |