projects / mirror_ubuntu-artful-kernel.git / blame
| Commit | Line | Data |
|---|---|---|
| d73cd428 NP |
1 | #ifndef _ASM_HIGHMEM_H |
| 2 | #define _ASM_HIGHMEM_H | |
| 3 | ||
| 4 | #include <asm/kmap_types.h> | |
| 5 | ||
| 6 | #define PKMAP_BASE (PAGE_OFFSET - PMD_SIZE) | |
| 7 | #define LAST_PKMAP PTRS_PER_PTE | |
| 8 | #define LAST_PKMAP_MASK (LAST_PKMAP - 1) | |
| 9 | #define PKMAP_NR(virt) (((virt) - PKMAP_BASE) >> PAGE_SHIFT) | |
| 10 | #define PKMAP_ADDR(nr) (PKMAP_BASE + ((nr) << PAGE_SHIFT)) | |
| 11 | ||
| 12 | #define kmap_prot PAGE_KERNEL | |
| 13 | ||
| 7e5a69e8 NP |
14 | #define flush_cache_kmaps() \ |
| 15 | do { \ | |
| 16 | if (cache_is_vivt()) \ | |
| 17 | flush_cache_all(); \ | |
| 18 | } while (0) | |
| d73cd428 NP |
19 | |
| 20 | extern pte_t *pkmap_page_table; | |
| a05e54c1 | 21 | extern pte_t *fixmap_page_table; |
| d73cd428 | 22 | |
| aaa50048 NP |
23 | extern void *kmap_high(struct page *page); |
| 24 | extern void kunmap_high(struct page *page); | |
| 25 | ||
| 26 | /* | |
| 27 | * The reason for kmap_high_get() is to ensure that the currently kmap'd | |
| 28 | * page usage count does not decrease to zero while we're using its | |
| 29 | * existing virtual mapping in an atomic context. With a VIVT cache this | |
| 30 | * is essential to do, but with a VIPT cache this is only an optimization | |
| 31 | * so not to pay the price of establishing a second mapping if an existing | |
| 32 | * one can be used. However, on platforms without hardware TLB maintenance | |
| 33 | * broadcast, we simply cannot use ARCH_NEEDS_KMAP_HIGH_GET at all since | |
| 34 | * the locking involved must also disable IRQs which is incompatible with | |
| 35 | * the IPI mechanism used by global TLB operations. | |
| 36 | */ | |
| 43377453 | 37 | #define ARCH_NEEDS_KMAP_HIGH_GET |
| aaa50048 NP |
38 | #if defined(CONFIG_SMP) && defined(CONFIG_CPU_TLB_V6) |
| 39 | #undef ARCH_NEEDS_KMAP_HIGH_GET | |
| 40 | #if defined(CONFIG_HIGHMEM) && defined(CONFIG_CPU_CACHE_VIVT) | |
| 41 | #error "The sum of features in your kernel config cannot be supported together" | |
| 42 | #endif | |
| 43 | #endif | |
| 43377453 | 44 | |
| 93dc6887 CM |
45 | /* |
| 46 | * Needed to be able to broadcast the TLB invalidation for kmap. | |
| 47 | */ | |
| 48 | #ifdef CONFIG_ARM_ERRATA_798181 | |
| 49 | #undef ARCH_NEEDS_KMAP_HIGH_GET | |
| 50 | #endif | |
| 51 | ||
| aaa50048 | 52 | #ifdef ARCH_NEEDS_KMAP_HIGH_GET |
| 43377453 | 53 | extern void *kmap_high_get(struct page *page); |
| aaa50048 NP |
54 | #else |
| 55 | static inline void *kmap_high_get(struct page *page) | |
| 56 | { | |
| 57 | return NULL; | |
| 58 | } | |
| 59 | #endif | |
| d73cd428 | 60 | |
| 7e5a69e8 NP |
61 | /* |
| 62 | * The following functions are already defined by <linux/highmem.h> | |
| 63 | * when CONFIG_HIGHMEM is not set. | |
| 64 | */ | |
| 65 | #ifdef CONFIG_HIGHMEM | |
| d73cd428 NP |
66 | extern void *kmap(struct page *page); |
| 67 | extern void kunmap(struct page *page); | |
| a24401bc | 68 | extern void *kmap_atomic(struct page *page); |
| 3e4d3af5 PZ |
69 | extern void __kunmap_atomic(void *kvaddr); |
| 70 | extern void *kmap_atomic_pfn(unsigned long pfn); | |
| 7e5a69e8 | 71 | #endif |
| d73cd428 NP |
72 | |
| 73 | #endif |