diff options
Diffstat (limited to 'arch/xtensa')
| -rw-r--r-- | arch/xtensa/include/asm/fixmap.h | 27 | ||||
| -rw-r--r-- | arch/xtensa/mm/highmem.c | 6 |
2 files changed, 27 insertions, 6 deletions
diff --git a/arch/xtensa/include/asm/fixmap.h b/arch/xtensa/include/asm/fixmap.h index 9f6c33d0428a..a43cd5265556 100644 --- a/arch/xtensa/include/asm/fixmap.h +++ b/arch/xtensa/include/asm/fixmap.h @@ -23,8 +23,8 @@ * Here we define all the compile-time 'special' virtual * addresses. The point is to have a constant address at * compile time, but to set the physical address only - * in the boot process. We allocate these special addresses - * from the end of the consistent memory region backwards. + * in the boot process. We allocate these special addresses + * from the start of the consistent memory region upwards. * Also this lets us do fail-safe vmalloc(), we * can guarantee that these special addresses and * vmalloc()-ed addresses never overlap. @@ -47,7 +47,28 @@ enum fixed_addresses { #define FIXADDR_SIZE (__end_of_fixed_addresses << PAGE_SHIFT) #define FIXADDR_START ((FIXADDR_TOP - FIXADDR_SIZE) & PMD_MASK) -#include <asm-generic/fixmap.h> +#define __fix_to_virt(x) (FIXADDR_START + ((x) << PAGE_SHIFT)) +#define __virt_to_fix(x) (((x) - FIXADDR_START) >> PAGE_SHIFT) + +#ifndef __ASSEMBLY__ +/* + * 'index to address' translation. If anyone tries to use the idx + * directly without translation, we catch the bug with a NULL-deference + * kernel oops. Illegal ranges of incoming indices are caught too. + */ +static __always_inline unsigned long fix_to_virt(const unsigned int idx) +{ + BUILD_BUG_ON(idx >= __end_of_fixed_addresses); + return __fix_to_virt(idx); +} + +static inline unsigned long virt_to_fix(const unsigned long vaddr) +{ + BUG_ON(vaddr >= FIXADDR_TOP || vaddr < FIXADDR_START); + return __virt_to_fix(vaddr); +} + +#endif #define kmap_get_fixmap_pte(vaddr) \ pte_offset_kernel( \ diff --git a/arch/xtensa/mm/highmem.c b/arch/xtensa/mm/highmem.c index 17a8c0d6fd17..2e95a7665bf3 100644 --- a/arch/xtensa/mm/highmem.c +++ b/arch/xtensa/mm/highmem.c @@ -28,9 +28,9 @@ void *kmap_atomic(struct page *page) idx = type + KM_TYPE_NR * smp_processor_id(); vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx); #ifdef CONFIG_DEBUG_HIGHMEM - BUG_ON(!pte_none(*(kmap_pte - idx))); + BUG_ON(!pte_none(*(kmap_pte + idx))); #endif - set_pte(kmap_pte - idx, mk_pte(page, PAGE_KERNEL_EXEC)); + set_pte(kmap_pte + idx, mk_pte(page, PAGE_KERNEL_EXEC)); return (void *)vaddr; } @@ -51,7 +51,7 @@ void __kunmap_atomic(void *kvaddr) * is a bad idea also, in case the page changes cacheability * attributes or becomes a protected page in a hypervisor. */ - pte_clear(&init_mm, kvaddr, kmap_pte - idx); + pte_clear(&init_mm, kvaddr, kmap_pte + idx); local_flush_tlb_kernel_range((unsigned long)kvaddr, (unsigned long)kvaddr + PAGE_SIZE); |