diff options
Diffstat (limited to 'arch/arm/mm/highmem.c')
| -rw-r--r-- | arch/arm/mm/highmem.c | 111 |
1 files changed, 15 insertions, 96 deletions
diff --git a/arch/arm/mm/highmem.c b/arch/arm/mm/highmem.c index 1fbdb55bfd1b..807c0573abbe 100644 --- a/arch/arm/mm/highmem.c +++ b/arch/arm/mm/highmem.c | |||
| @@ -36,18 +36,17 @@ void kunmap(struct page *page) | |||
| 36 | } | 36 | } |
| 37 | EXPORT_SYMBOL(kunmap); | 37 | EXPORT_SYMBOL(kunmap); |
| 38 | 38 | ||
| 39 | void *kmap_atomic(struct page *page, enum km_type type) | 39 | void *__kmap_atomic(struct page *page) |
| 40 | { | 40 | { |
| 41 | unsigned int idx; | 41 | unsigned int idx; |
| 42 | unsigned long vaddr; | 42 | unsigned long vaddr; |
| 43 | void *kmap; | 43 | void *kmap; |
| 44 | int type; | ||
| 44 | 45 | ||
| 45 | pagefault_disable(); | 46 | pagefault_disable(); |
| 46 | if (!PageHighMem(page)) | 47 | if (!PageHighMem(page)) |
| 47 | return page_address(page); | 48 | return page_address(page); |
| 48 | 49 | ||
| 49 | debug_kmap_atomic(type); | ||
| 50 | |||
| 51 | #ifdef CONFIG_DEBUG_HIGHMEM | 50 | #ifdef CONFIG_DEBUG_HIGHMEM |
| 52 | /* | 51 | /* |
| 53 | * There is no cache coherency issue when non VIVT, so force the | 52 | * There is no cache coherency issue when non VIVT, so force the |
| @@ -61,6 +60,8 @@ void *kmap_atomic(struct page *page, enum km_type type) | |||
| 61 | if (kmap) | 60 | if (kmap) |
| 62 | return kmap; | 61 | return kmap; |
| 63 | 62 | ||
| 63 | type = kmap_atomic_idx_push(); | ||
| 64 | |||
| 64 | idx = type + KM_TYPE_NR * smp_processor_id(); | 65 | idx = type + KM_TYPE_NR * smp_processor_id(); |
| 65 | vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx); | 66 | vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx); |
| 66 | #ifdef CONFIG_DEBUG_HIGHMEM | 67 | #ifdef CONFIG_DEBUG_HIGHMEM |
| @@ -80,14 +81,17 @@ void *kmap_atomic(struct page *page, enum km_type type) | |||
| 80 | 81 | ||
| 81 | return (void *)vaddr; | 82 | return (void *)vaddr; |
| 82 | } | 83 | } |
| 83 | EXPORT_SYMBOL(kmap_atomic); | 84 | EXPORT_SYMBOL(__kmap_atomic); |
| 84 | 85 | ||
| 85 | void kunmap_atomic_notypecheck(void *kvaddr, enum km_type type) | 86 | void __kunmap_atomic(void *kvaddr) |
| 86 | { | 87 | { |
| 87 | unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK; | 88 | unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK; |
| 88 | unsigned int idx = type + KM_TYPE_NR * smp_processor_id(); | 89 | int idx, type; |
| 89 | 90 | ||
| 90 | if (kvaddr >= (void *)FIXADDR_START) { | 91 | if (kvaddr >= (void *)FIXADDR_START) { |
| 92 | type = kmap_atomic_idx(); | ||
| 93 | idx = type + KM_TYPE_NR * smp_processor_id(); | ||
| 94 | |||
| 91 | if (cache_is_vivt()) | 95 | if (cache_is_vivt()) |
| 92 | __cpuc_flush_dcache_area((void *)vaddr, PAGE_SIZE); | 96 | __cpuc_flush_dcache_area((void *)vaddr, PAGE_SIZE); |
| 93 | #ifdef CONFIG_DEBUG_HIGHMEM | 97 | #ifdef CONFIG_DEBUG_HIGHMEM |
| @@ -97,21 +101,23 @@ void kunmap_atomic_notypecheck(void *kvaddr, enum km_type type) | |||
| 97 | #else | 101 | #else |
| 98 | (void) idx; /* to kill a warning */ | 102 | (void) idx; /* to kill a warning */ |
| 99 | #endif | 103 | #endif |
| 104 | kmap_atomic_idx_pop(); | ||
| 100 | } else if (vaddr >= PKMAP_ADDR(0) && vaddr < PKMAP_ADDR(LAST_PKMAP)) { | 105 | } else if (vaddr >= PKMAP_ADDR(0) && vaddr < PKMAP_ADDR(LAST_PKMAP)) { |
| 101 | /* this address was obtained through kmap_high_get() */ | 106 | /* this address was obtained through kmap_high_get() */ |
| 102 | kunmap_high(pte_page(pkmap_page_table[PKMAP_NR(vaddr)])); | 107 | kunmap_high(pte_page(pkmap_page_table[PKMAP_NR(vaddr)])); |
| 103 | } | 108 | } |
| 104 | pagefault_enable(); | 109 | pagefault_enable(); |
| 105 | } | 110 | } |
| 106 | EXPORT_SYMBOL(kunmap_atomic_notypecheck); | 111 | EXPORT_SYMBOL(__kunmap_atomic); |
| 107 | 112 | ||
| 108 | void *kmap_atomic_pfn(unsigned long pfn, enum km_type type) | 113 | void *kmap_atomic_pfn(unsigned long pfn) |
| 109 | { | 114 | { |
| 110 | unsigned int idx; | ||
| 111 | unsigned long vaddr; | 115 | unsigned long vaddr; |
| 116 | int idx, type; | ||
| 112 | 117 | ||
| 113 | pagefault_disable(); | 118 | pagefault_disable(); |
| 114 | 119 | ||
| 120 | type = kmap_atomic_idx_push(); | ||
| 115 | idx = type + KM_TYPE_NR * smp_processor_id(); | 121 | idx = type + KM_TYPE_NR * smp_processor_id(); |
| 116 | vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx); | 122 | vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx); |
| 117 | #ifdef CONFIG_DEBUG_HIGHMEM | 123 | #ifdef CONFIG_DEBUG_HIGHMEM |
| @@ -134,90 +140,3 @@ struct page *kmap_atomic_to_page(const void *ptr) | |||
| 134 | pte = TOP_PTE(vaddr); | 140 | pte = TOP_PTE(vaddr); |
| 135 | return pte_page(*pte); | 141 | return pte_page(*pte); |
| 136 | } | 142 | } |
| 137 | |||
| 138 | #ifdef CONFIG_CPU_CACHE_VIPT | ||
| 139 | |||
| 140 | #include <linux/percpu.h> | ||
| 141 | |||
| 142 | /* | ||
| 143 | * The VIVT cache of a highmem page is always flushed before the page | ||
| 144 | * is unmapped. Hence unmapped highmem pages need no cache maintenance | ||
| 145 | * in that case. | ||
| 146 | * | ||
| 147 | * However unmapped pages may still be cached with a VIPT cache, and | ||
| 148 | * it is not possible to perform cache maintenance on them using physical | ||
| 149 | * addresses unfortunately. So we have no choice but to set up a temporary | ||
| 150 | * virtual mapping for that purpose. | ||
| 151 | * | ||
| 152 | * Yet this VIPT cache maintenance may be triggered from DMA support | ||
| 153 | * functions which are possibly called from interrupt context. As we don't | ||
| 154 | * want to keep interrupt disabled all the time when such maintenance is | ||
| 155 | * taking place, we therefore allow for some reentrancy by preserving and | ||
| 156 | * restoring the previous fixmap entry before the interrupted context is | ||
| 157 | * resumed. If the reentrancy depth is 0 then there is no need to restore | ||
| 158 | * the previous fixmap, and leaving the current one in place allow it to | ||
| 159 | * be reused the next time without a TLB flush (common with DMA). | ||
| 160 | */ | ||
| 161 | |||
| 162 | static DEFINE_PER_CPU(int, kmap_high_l1_vipt_depth); | ||
| 163 | |||
| 164 | void *kmap_high_l1_vipt(struct page *page, pte_t *saved_pte) | ||
| 165 | { | ||
| 166 | unsigned int idx, cpu; | ||
| 167 | int *depth; | ||
| 168 | unsigned long vaddr, flags; | ||
| 169 | pte_t pte, *ptep; | ||
| 170 | |||
| 171 | if (!in_interrupt()) | ||
| 172 | preempt_disable(); | ||
| 173 | |||
| 174 | cpu = smp_processor_id(); | ||
| 175 | depth = &per_cpu(kmap_high_l1_vipt_depth, cpu); | ||
| 176 | |||
| 177 | idx = KM_L1_CACHE + KM_TYPE_NR * cpu; | ||
| 178 | vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx); | ||
| 179 | ptep = TOP_PTE(vaddr); | ||
| 180 | pte = mk_pte(page, kmap_prot); | ||
| 181 | |||
| 182 | raw_local_irq_save(flags); | ||
| 183 | (*depth)++; | ||
| 184 | if (pte_val(*ptep) == pte_val(pte)) { | ||
| 185 | *saved_pte = pte; | ||
| 186 | } else { | ||
| 187 | *saved_pte = *ptep; | ||
| 188 | set_pte_ext(ptep, pte, 0); | ||
| 189 | local_flush_tlb_kernel_page(vaddr); | ||
| 190 | } | ||
| 191 | raw_local_irq_restore(flags); | ||
| 192 | |||
| 193 | return (void *)vaddr; | ||
| 194 | } | ||
| 195 | |||
| 196 | void kunmap_high_l1_vipt(struct page *page, pte_t saved_pte) | ||
| 197 | { | ||
| 198 | unsigned int idx, cpu = smp_processor_id(); | ||
| 199 | int *depth = &per_cpu(kmap_high_l1_vipt_depth, cpu); | ||
| 200 | unsigned long vaddr, flags; | ||
| 201 | pte_t pte, *ptep; | ||
| 202 | |||
| 203 | idx = KM_L1_CACHE + KM_TYPE_NR * cpu; | ||
| 204 | vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx); | ||
| 205 | ptep = TOP_PTE(vaddr); | ||
| 206 | pte = mk_pte(page, kmap_prot); | ||
| 207 | |||
| 208 | BUG_ON(pte_val(*ptep) != pte_val(pte)); | ||
| 209 | BUG_ON(*depth <= 0); | ||
| 210 | |||
| 211 | raw_local_irq_save(flags); | ||
| 212 | (*depth)--; | ||
| 213 | if (*depth != 0 && pte_val(pte) != pte_val(saved_pte)) { | ||
| 214 | set_pte_ext(ptep, saved_pte, 0); | ||
| 215 | local_flush_tlb_kernel_page(vaddr); | ||
| 216 | } | ||
| 217 | raw_local_irq_restore(flags); | ||
| 218 | |||
| 219 | if (!in_interrupt()) | ||
| 220 | preempt_enable(); | ||
| 221 | } | ||
| 222 | |||
| 223 | #endif /* CONFIG_CPU_CACHE_VIPT */ | ||
