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 */ | ||