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