diff options
Diffstat (limited to 'include/linux/highmem-internal.h')
| -rw-r--r-- | include/linux/highmem-internal.h | 48 |
1 files changed, 40 insertions, 8 deletions
diff --git a/include/linux/highmem-internal.h b/include/linux/highmem-internal.h index 0a0b2b09b1b8..034b1106d022 100644 --- a/include/linux/highmem-internal.h +++ b/include/linux/highmem-internal.h @@ -8,7 +8,7 @@ #ifdef CONFIG_KMAP_LOCAL void *__kmap_local_pfn_prot(unsigned long pfn, pgprot_t prot); void *__kmap_local_page_prot(struct page *page, pgprot_t prot); -void kunmap_local_indexed(void *vaddr); +void kunmap_local_indexed(const void *vaddr); void kmap_local_fork(struct task_struct *tsk); void __kmap_local_sched_out(void); void __kmap_local_sched_in(void); @@ -89,7 +89,7 @@ static inline void *kmap_local_pfn(unsigned long pfn) return __kmap_local_pfn_prot(pfn, kmap_prot); } -static inline void __kunmap_local(void *vaddr) +static inline void __kunmap_local(const void *vaddr) { kunmap_local_indexed(vaddr); } @@ -121,7 +121,7 @@ static inline void *kmap_atomic_pfn(unsigned long pfn) return __kmap_local_pfn_prot(pfn, kmap_prot); } -static inline void __kunmap_atomic(void *addr) +static inline void __kunmap_atomic(const void *addr) { kunmap_local_indexed(addr); pagefault_enable(); @@ -149,6 +149,11 @@ static inline void totalhigh_pages_add(long count) atomic_long_add(count, &_totalhigh_pages); } +static inline bool is_kmap_addr(const void *x) +{ + unsigned long addr = (unsigned long)x; + return addr >= PKMAP_ADDR(0) && addr < PKMAP_ADDR(LAST_PKMAP); +} #else /* CONFIG_HIGHMEM */ static inline struct page *kmap_to_page(void *addr) @@ -192,7 +197,7 @@ static inline void *kmap_local_pfn(unsigned long pfn) return kmap_local_page(pfn_to_page(pfn)); } -static inline void __kunmap_local(void *addr) +static inline void __kunmap_local(const void *addr) { #ifdef ARCH_HAS_FLUSH_ON_KUNMAP kunmap_flush_on_unmap(addr); @@ -219,7 +224,7 @@ static inline void *kmap_atomic_pfn(unsigned long pfn) return kmap_atomic(pfn_to_page(pfn)); } -static inline void __kunmap_atomic(void *addr) +static inline void __kunmap_atomic(const void *addr) { #ifdef ARCH_HAS_FLUSH_ON_KUNMAP kunmap_flush_on_unmap(addr); @@ -234,11 +239,28 @@ static inline void __kunmap_atomic(void *addr) static inline unsigned int nr_free_highpages(void) { return 0; } static inline unsigned long totalhigh_pages(void) { return 0UL; } +static inline bool is_kmap_addr(const void *x) +{ + return false; +} + #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. +/** + * kunmap_atomic - Unmap the virtual address mapped by kmap_atomic() - deprecated! + * @__addr: Virtual address to be unmapped + * + * Unmaps an address previously mapped by kmap_atomic() and re-enables + * pagefaults. Depending on PREEMP_RT configuration, re-enables also + * migration and preemption. Users should not count on these side effects. + * + * Mappings should be unmapped in the reverse order that they were mapped. + * See kmap_local_page() for details on nesting. + * + * @__addr can be any address within the mapped page, so there is no need + * to subtract any offset that has been added. In contrast to kunmap(), + * this function takes the address returned from kmap_atomic(), not the + * page passed to it. The compiler will warn you if you pass the page. */ #define kunmap_atomic(__addr) \ do { \ @@ -246,6 +268,16 @@ do { \ __kunmap_atomic(__addr); \ } while (0) +/** + * kunmap_local - Unmap a page mapped via kmap_local_page(). + * @__addr: An address within the page mapped + * + * @__addr can be any address within the mapped page. Commonly it is the + * address return from kmap_local_page(), but it can also include offsets. + * + * Unmapping should be done in the reverse order of the mapping. See + * kmap_local_page() for details. + */ #define kunmap_local(__addr) \ do { \ BUILD_BUG_ON(__same_type((__addr), struct page *)); \ |