diff options
Diffstat (limited to 'include/linux/highmem.h')
| -rw-r--r-- | include/linux/highmem.h | 74 |
1 files changed, 50 insertions, 24 deletions
diff --git a/include/linux/highmem.h b/include/linux/highmem.h index e3060ef85b6d..e9138198e823 100644 --- a/include/linux/highmem.h +++ b/include/linux/highmem.h @@ -28,18 +28,6 @@ static inline void invalidate_kernel_vmap_range(void *vaddr, int size) #include <asm/kmap_types.h> -#ifdef CONFIG_DEBUG_HIGHMEM - -void debug_kmap_atomic(enum km_type type); - -#else - -static inline void debug_kmap_atomic(enum km_type type) -{ -} - -#endif - #ifdef CONFIG_HIGHMEM #include <asm/highmem.h> @@ -66,19 +54,19 @@ static inline void kunmap(struct page *page) { } -static inline void *kmap_atomic(struct page *page, enum km_type idx) +static inline void *__kmap_atomic(struct page *page) { pagefault_disable(); return page_address(page); } -#define kmap_atomic_prot(page, idx, prot) kmap_atomic(page, idx) +#define kmap_atomic_prot(page, prot) __kmap_atomic(page) -static inline void kunmap_atomic_notypecheck(void *addr, enum km_type idx) +static inline void __kunmap_atomic(void *addr) { pagefault_enable(); } -#define kmap_atomic_pfn(pfn, idx) kmap_atomic(pfn_to_page(pfn), (idx)) +#define kmap_atomic_pfn(pfn) kmap_atomic(pfn_to_page(pfn)) #define kmap_atomic_to_page(ptr) virt_to_page(ptr) #define kmap_flush_unused() do {} while(0) @@ -86,12 +74,50 @@ static inline void kunmap_atomic_notypecheck(void *addr, enum km_type idx) #endif /* CONFIG_HIGHMEM */ -/* Prevent people trying to call kunmap_atomic() as if it were kunmap() */ -/* kunmap_atomic() should get the return value of kmap_atomic, not the page. */ -#define kunmap_atomic(addr, idx) do { \ - BUILD_BUG_ON(__same_type((addr), struct page *)); \ - kunmap_atomic_notypecheck((addr), (idx)); \ - } while (0) +#if defined(CONFIG_HIGHMEM) || defined(CONFIG_X86_32) + +DECLARE_PER_CPU(int, __kmap_atomic_idx); + +static inline int kmap_atomic_idx_push(void) +{ + int idx = __get_cpu_var(__kmap_atomic_idx)++; +#ifdef CONFIG_DEBUG_HIGHMEM + WARN_ON_ONCE(in_irq() && !irqs_disabled()); + BUG_ON(idx > KM_TYPE_NR); +#endif + return idx; +} + +static inline int kmap_atomic_idx(void) +{ + return __get_cpu_var(__kmap_atomic_idx) - 1; +} + +static inline int kmap_atomic_idx_pop(void) +{ + int idx = --__get_cpu_var(__kmap_atomic_idx); +#ifdef CONFIG_DEBUG_HIGHMEM + BUG_ON(idx < 0); +#endif + return idx; +} + +#endif + +/* + * Make both: kmap_atomic(page, idx) and kmap_atomic(page) work. + */ +#define kmap_atomic(page, args...) __kmap_atomic(page) + +/* + * Prevent people trying to call kunmap_atomic() as if it were kunmap() + * kunmap_atomic() should get the return value of kmap_atomic, not the page. + */ +#define kunmap_atomic(addr, args...) \ +do { \ + BUILD_BUG_ON(__same_type((addr), struct page *)); \ + __kunmap_atomic(addr); \ +} while (0) /* when CONFIG_HIGHMEM is not set these will be plain clear/copy_page */ #ifndef clear_user_highpage @@ -201,8 +227,8 @@ static inline void copy_user_highpage(struct page *to, struct page *from, vfrom = kmap_atomic(from, KM_USER0); vto = kmap_atomic(to, KM_USER1); copy_user_page(vto, vfrom, vaddr, to); - kunmap_atomic(vfrom, KM_USER0); kunmap_atomic(vto, KM_USER1); + kunmap_atomic(vfrom, KM_USER0); } #endif @@ -214,8 +240,8 @@ static inline void copy_highpage(struct page *to, struct page *from) vfrom = kmap_atomic(from, KM_USER0); vto = kmap_atomic(to, KM_USER1); copy_page(vto, vfrom); - kunmap_atomic(vfrom, KM_USER0); kunmap_atomic(vto, KM_USER1); + kunmap_atomic(vfrom, KM_USER0); } #endif /* _LINUX_HIGHMEM_H */ |