diff options
Diffstat (limited to 'arch/x86')
| -rw-r--r-- | arch/x86/include/asm/io.h | 4 | ||||
| -rw-r--r-- | arch/x86/mm/mmap.c | 16 |
2 files changed, 20 insertions, 0 deletions
diff --git a/arch/x86/include/asm/io.h b/arch/x86/include/asm/io.h index 93ae8aee1780..95e948627fd0 100644 --- a/arch/x86/include/asm/io.h +++ b/arch/x86/include/asm/io.h @@ -111,6 +111,10 @@ build_mmio_write(__writeq, "q", unsigned long, "r", ) #endif +#define ARCH_HAS_VALID_PHYS_ADDR_RANGE +extern int valid_phys_addr_range(phys_addr_t addr, size_t size); +extern int valid_mmap_phys_addr_range(unsigned long pfn, size_t size); + /** * virt_to_phys - map virtual addresses to physical * @address: address to remap diff --git a/arch/x86/mm/mmap.c b/arch/x86/mm/mmap.c index 62285fe77b0f..155ecbac9e28 100644 --- a/arch/x86/mm/mmap.c +++ b/arch/x86/mm/mmap.c @@ -33,6 +33,8 @@ #include <linux/compat.h> #include <asm/elf.h> +#include "physaddr.h" + struct va_alignment __read_mostly va_align = { .flags = -1, }; @@ -220,3 +222,17 @@ bool mmap_address_hint_valid(unsigned long addr, unsigned long len) return (addr > DEFAULT_MAP_WINDOW) == (addr + len > DEFAULT_MAP_WINDOW); } + +/* Can we access it for direct reading/writing? Must be RAM: */ +int valid_phys_addr_range(phys_addr_t addr, size_t count) +{ + return addr + count <= __pa(high_memory); +} + +/* Can we access it through mmap? Must be a valid physical address: */ +int valid_mmap_phys_addr_range(unsigned long pfn, size_t count) +{ + phys_addr_t addr = (phys_addr_t)pfn << PAGE_SHIFT; + + return phys_addr_valid(addr + count - 1); +} |