1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef __ASM_POWERPC_MMU_CONTEXT_H 3 #define __ASM_POWERPC_MMU_CONTEXT_H 4 #ifdef __KERNEL__ 5 6 #include <linux/kernel.h> 7 #include <linux/mm.h> 8 #include <linux/sched.h> 9 #include <linux/spinlock.h> 10 #include <asm/mmu.h> 11 #include <asm/cputable.h> 12 #include <asm/cputhreads.h> 13 14 /* 15 * Most if the context management is out of line 16 */ 17 #define init_new_context init_new_context 18 extern int init_new_context(struct task_struct *tsk, struct mm_struct *mm); 19 #define destroy_context destroy_context 20 extern void destroy_context(struct mm_struct *mm); 21 #ifdef CONFIG_SPAPR_TCE_IOMMU 22 struct mm_iommu_table_group_mem_t; 23 24 extern int isolate_lru_page(struct page *page); /* from internal.h */ 25 extern bool mm_iommu_preregistered(struct mm_struct *mm); 26 extern long mm_iommu_new(struct mm_struct *mm, 27 unsigned long ua, unsigned long entries, 28 struct mm_iommu_table_group_mem_t **pmem); 29 extern long mm_iommu_newdev(struct mm_struct *mm, unsigned long ua, 30 unsigned long entries, unsigned long dev_hpa, 31 struct mm_iommu_table_group_mem_t **pmem); 32 extern long mm_iommu_put(struct mm_struct *mm, 33 struct mm_iommu_table_group_mem_t *mem); 34 extern void mm_iommu_init(struct mm_struct *mm); 35 extern void mm_iommu_cleanup(struct mm_struct *mm); 36 extern struct mm_iommu_table_group_mem_t *mm_iommu_lookup(struct mm_struct *mm, 37 unsigned long ua, unsigned long size); 38 extern struct mm_iommu_table_group_mem_t *mm_iommu_lookup_rm( 39 struct mm_struct *mm, unsigned long ua, unsigned long size); 40 extern struct mm_iommu_table_group_mem_t *mm_iommu_get(struct mm_struct *mm, 41 unsigned long ua, unsigned long entries); 42 extern long mm_iommu_ua_to_hpa(struct mm_iommu_table_group_mem_t *mem, 43 unsigned long ua, unsigned int pageshift, unsigned long *hpa); 44 extern long mm_iommu_ua_to_hpa_rm(struct mm_iommu_table_group_mem_t *mem, 45 unsigned long ua, unsigned int pageshift, unsigned long *hpa); 46 extern void mm_iommu_ua_mark_dirty_rm(struct mm_struct *mm, unsigned long ua); 47 extern bool mm_iommu_is_devmem(struct mm_struct *mm, unsigned long hpa, 48 unsigned int pageshift, unsigned long *size); 49 extern long mm_iommu_mapped_inc(struct mm_iommu_table_group_mem_t *mem); 50 extern void mm_iommu_mapped_dec(struct mm_iommu_table_group_mem_t *mem); 51 #else 52 static inline bool mm_iommu_is_devmem(struct mm_struct *mm, unsigned long hpa, 53 unsigned int pageshift, unsigned long *size) 54 { 55 return false; 56 } 57 static inline void mm_iommu_init(struct mm_struct *mm) { } 58 #endif 59 extern void switch_slb(struct task_struct *tsk, struct mm_struct *mm); 60 extern void set_context(unsigned long id, pgd_t *pgd); 61 62 #ifdef CONFIG_PPC_BOOK3S_64 63 extern void radix__switch_mmu_context(struct mm_struct *prev, 64 struct mm_struct *next); 65 static inline void switch_mmu_context(struct mm_struct *prev, 66 struct mm_struct *next, 67 struct task_struct *tsk) 68 { 69 if (radix_enabled()) 70 return radix__switch_mmu_context(prev, next); 71 return switch_slb(tsk, next); 72 } 73 74 extern int hash__alloc_context_id(void); 75 extern void hash__reserve_context_id(int id); 76 extern void __destroy_context(int context_id); 77 static inline void mmu_context_init(void) { } 78 79 static inline int alloc_extended_context(struct mm_struct *mm, 80 unsigned long ea) 81 { 82 int context_id; 83 84 int index = ea >> MAX_EA_BITS_PER_CONTEXT; 85 86 context_id = hash__alloc_context_id(); 87 if (context_id < 0) 88 return context_id; 89 90 VM_WARN_ON(mm->context.extended_id[index]); 91 mm->context.extended_id[index] = context_id; 92 return context_id; 93 } 94 95 static inline bool need_extra_context(struct mm_struct *mm, unsigned long ea) 96 { 97 int context_id; 98 99 context_id = get_user_context(&mm->context, ea); 100 if (!context_id) 101 return true; 102 return false; 103 } 104 105 #else 106 extern void switch_mmu_context(struct mm_struct *prev, struct mm_struct *next, 107 struct task_struct *tsk); 108 extern unsigned long __init_new_context(void); 109 extern void __destroy_context(unsigned long context_id); 110 extern void mmu_context_init(void); 111 static inline int alloc_extended_context(struct mm_struct *mm, 112 unsigned long ea) 113 { 114 /* non book3s_64 should never find this called */ 115 WARN_ON(1); 116 return -ENOMEM; 117 } 118 119 static inline bool need_extra_context(struct mm_struct *mm, unsigned long ea) 120 { 121 return false; 122 } 123 #endif 124 125 #if defined(CONFIG_KVM_BOOK3S_HV_POSSIBLE) && defined(CONFIG_PPC_RADIX_MMU) 126 extern void radix_kvm_prefetch_workaround(struct mm_struct *mm); 127 #else 128 static inline void radix_kvm_prefetch_workaround(struct mm_struct *mm) { } 129 #endif 130 131 extern void switch_cop(struct mm_struct *next); 132 extern int use_cop(unsigned long acop, struct mm_struct *mm); 133 extern void drop_cop(unsigned long acop, struct mm_struct *mm); 134 135 #ifdef CONFIG_PPC_BOOK3S_64 136 static inline void inc_mm_active_cpus(struct mm_struct *mm) 137 { 138 atomic_inc(&mm->context.active_cpus); 139 } 140 141 static inline void dec_mm_active_cpus(struct mm_struct *mm) 142 { 143 atomic_dec(&mm->context.active_cpus); 144 } 145 146 static inline void mm_context_add_copro(struct mm_struct *mm) 147 { 148 /* 149 * If any copro is in use, increment the active CPU count 150 * in order to force TLB invalidations to be global as to 151 * propagate to the Nest MMU. 152 */ 153 if (atomic_inc_return(&mm->context.copros) == 1) 154 inc_mm_active_cpus(mm); 155 } 156 157 static inline void mm_context_remove_copro(struct mm_struct *mm) 158 { 159 int c; 160 161 /* 162 * When removing the last copro, we need to broadcast a global 163 * flush of the full mm, as the next TLBI may be local and the 164 * nMMU and/or PSL need to be cleaned up. 165 * 166 * Both the 'copros' and 'active_cpus' counts are looked at in 167 * flush_all_mm() to determine the scope (local/global) of the 168 * TLBIs, so we need to flush first before decrementing 169 * 'copros'. If this API is used by several callers for the 170 * same context, it can lead to over-flushing. It's hopefully 171 * not common enough to be a problem. 172 * 173 * Skip on hash, as we don't know how to do the proper flush 174 * for the time being. Invalidations will remain global if 175 * used on hash. Note that we can't drop 'copros' either, as 176 * it could make some invalidations local with no flush 177 * in-between. 178 */ 179 if (radix_enabled()) { 180 flush_all_mm(mm); 181 182 c = atomic_dec_if_positive(&mm->context.copros); 183 /* Detect imbalance between add and remove */ 184 WARN_ON(c < 0); 185 186 if (c == 0) 187 dec_mm_active_cpus(mm); 188 } 189 } 190 191 /* 192 * vas_windows counter shows number of open windows in the mm 193 * context. During context switch, use this counter to clear the 194 * foreign real address mapping (CP_ABORT) for the thread / process 195 * that intend to use COPY/PASTE. When a process closes all windows, 196 * disable CP_ABORT which is expensive to run. 197 * 198 * For user context, register a copro so that TLBIs are seen by the 199 * nest MMU. mm_context_add/remove_vas_window() are used only for user 200 * space windows. 201 */ 202 static inline void mm_context_add_vas_window(struct mm_struct *mm) 203 { 204 atomic_inc(&mm->context.vas_windows); 205 mm_context_add_copro(mm); 206 } 207 208 static inline void mm_context_remove_vas_window(struct mm_struct *mm) 209 { 210 int v; 211 212 mm_context_remove_copro(mm); 213 v = atomic_dec_if_positive(&mm->context.vas_windows); 214 215 /* Detect imbalance between add and remove */ 216 WARN_ON(v < 0); 217 } 218 #else 219 static inline void inc_mm_active_cpus(struct mm_struct *mm) { } 220 static inline void dec_mm_active_cpus(struct mm_struct *mm) { } 221 static inline void mm_context_add_copro(struct mm_struct *mm) { } 222 static inline void mm_context_remove_copro(struct mm_struct *mm) { } 223 #endif 224 225 226 extern void switch_mm_irqs_off(struct mm_struct *prev, struct mm_struct *next, 227 struct task_struct *tsk); 228 229 static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next, 230 struct task_struct *tsk) 231 { 232 unsigned long flags; 233 234 local_irq_save(flags); 235 switch_mm_irqs_off(prev, next, tsk); 236 local_irq_restore(flags); 237 } 238 #define switch_mm_irqs_off switch_mm_irqs_off 239 240 /* 241 * After we have set current->mm to a new value, this activates 242 * the context for the new mm so we see the new mappings. 243 */ 244 #define activate_mm activate_mm 245 static inline void activate_mm(struct mm_struct *prev, struct mm_struct *next) 246 { 247 switch_mm_irqs_off(prev, next, current); 248 } 249 250 /* We don't currently use enter_lazy_tlb() for anything */ 251 #ifdef CONFIG_PPC_BOOK3E_64 252 #define enter_lazy_tlb enter_lazy_tlb 253 static inline void enter_lazy_tlb(struct mm_struct *mm, 254 struct task_struct *tsk) 255 { 256 /* 64-bit Book3E keeps track of current PGD in the PACA */ 257 get_paca()->pgd = NULL; 258 } 259 #endif 260 261 extern void arch_exit_mmap(struct mm_struct *mm); 262 263 static inline void arch_unmap(struct mm_struct *mm, 264 unsigned long start, unsigned long end) 265 { 266 unsigned long vdso_base = (unsigned long)mm->context.vdso - PAGE_SIZE; 267 268 if (start <= vdso_base && vdso_base < end) 269 mm->context.vdso = NULL; 270 } 271 272 #ifdef CONFIG_PPC_MEM_KEYS 273 bool arch_vma_access_permitted(struct vm_area_struct *vma, bool write, 274 bool execute, bool foreign); 275 void arch_dup_pkeys(struct mm_struct *oldmm, struct mm_struct *mm); 276 #else /* CONFIG_PPC_MEM_KEYS */ 277 static inline bool arch_vma_access_permitted(struct vm_area_struct *vma, 278 bool write, bool execute, bool foreign) 279 { 280 /* by default, allow everything */ 281 return true; 282 } 283 284 #define pkey_mm_init(mm) 285 #define arch_dup_pkeys(oldmm, mm) 286 287 static inline u64 pte_to_hpte_pkey_bits(u64 pteflags, unsigned long flags) 288 { 289 return 0x0UL; 290 } 291 292 #endif /* CONFIG_PPC_MEM_KEYS */ 293 294 static inline int arch_dup_mmap(struct mm_struct *oldmm, 295 struct mm_struct *mm) 296 { 297 arch_dup_pkeys(oldmm, mm); 298 return 0; 299 } 300 301 #include <asm-generic/mmu_context.h> 302 303 #endif /* __KERNEL__ */ 304 #endif /* __ASM_POWERPC_MMU_CONTEXT_H */ 305