arch/powerpc/include/asm/mmu_context.h

   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 #endif
  56 extern void switch_slb(struct task_struct *tsk, struct mm_struct *mm);
  57 extern void set_context(unsigned long id, pgd_t *pgd);
  58
  59 #ifdef CONFIG_PPC_BOOK3S_64
  60 extern void radix__switch_mmu_context(struct mm_struct *prev,
  61                                       struct mm_struct *next);
  62 static inline void switch_mmu_context(struct mm_struct *prev,
  63                                       struct mm_struct *next,
  64                                       struct task_struct *tsk)
  65 {
  66         if (radix_enabled())
  67                 return radix__switch_mmu_context(prev, next);
  68         return switch_slb(tsk, next);
  69 }
  70
  71 extern int hash__alloc_context_id(void);
  72 extern void hash__reserve_context_id(int id);
  73 extern void __destroy_context(int context_id);
  74 static inline void mmu_context_init(void) { }
  75
  76 static inline int alloc_extended_context(struct mm_struct *mm,
  77                                          unsigned long ea)
  78 {
  79         int context_id;
  80
  81         int index = ea >> MAX_EA_BITS_PER_CONTEXT;
  82
  83         context_id = hash__alloc_context_id();
  84         if (context_id < 0)
  85                 return context_id;
  86
  87         VM_WARN_ON(mm->context.extended_id[index]);
  88         mm->context.extended_id[index] = context_id;
  89         return context_id;
  90 }
  91
  92 static inline bool need_extra_context(struct mm_struct *mm, unsigned long ea)
  93 {
  94         int context_id;
  95
  96         context_id = get_user_context(&mm->context, ea);
  97         if (!context_id)
  98                 return true;
  99         return false;
 100 }
 101
 102 #else
 103 extern void switch_mmu_context(struct mm_struct *prev, struct mm_struct *next,
 104                                struct task_struct *tsk);
 105 extern unsigned long __init_new_context(void);
 106 extern void __destroy_context(unsigned long context_id);
 107 extern void mmu_context_init(void);
 108 static inline int alloc_extended_context(struct mm_struct *mm,
 109                                          unsigned long ea)
 110 {
 111         /* non book3s_64 should never find this called */
 112         WARN_ON(1);
 113         return -ENOMEM;
 114 }
 115
 116 static inline bool need_extra_context(struct mm_struct *mm, unsigned long ea)
 117 {
 118         return false;
 119 }
 120 #endif
 121
 122 #if defined(CONFIG_KVM_BOOK3S_HV_POSSIBLE) && defined(CONFIG_PPC_RADIX_MMU)
 123 extern void radix_kvm_prefetch_workaround(struct mm_struct *mm);
 124 #else
 125 static inline void radix_kvm_prefetch_workaround(struct mm_struct *mm) { }
 126 #endif
 127
 128 extern void switch_cop(struct mm_struct *next);
 129 extern int use_cop(unsigned long acop, struct mm_struct *mm);
 130 extern void drop_cop(unsigned long acop, struct mm_struct *mm);
 131
 132 #ifdef CONFIG_PPC_BOOK3S_64
 133 static inline void inc_mm_active_cpus(struct mm_struct *mm)
 134 {
 135         atomic_inc(&mm->context.active_cpus);
 136 }
 137
 138 static inline void dec_mm_active_cpus(struct mm_struct *mm)
 139 {
 140         atomic_dec(&mm->context.active_cpus);
 141 }
 142
 143 static inline void mm_context_add_copro(struct mm_struct *mm)
 144 {
 145         /*
 146          * If any copro is in use, increment the active CPU count
 147          * in order to force TLB invalidations to be global as to
 148          * propagate to the Nest MMU.
 149          */
 150         if (atomic_inc_return(&mm->context.copros) == 1)
 151                 inc_mm_active_cpus(mm);
 152 }
 153
 154 static inline void mm_context_remove_copro(struct mm_struct *mm)
 155 {
 156         int c;
 157
 158         /*
 159          * When removing the last copro, we need to broadcast a global
 160          * flush of the full mm, as the next TLBI may be local and the
 161          * nMMU and/or PSL need to be cleaned up.
 162          *
 163          * Both the 'copros' and 'active_cpus' counts are looked at in
 164          * flush_all_mm() to determine the scope (local/global) of the
 165          * TLBIs, so we need to flush first before decrementing
 166          * 'copros'. If this API is used by several callers for the
 167          * same context, it can lead to over-flushing. It's hopefully
 168          * not common enough to be a problem.
 169          *
 170          * Skip on hash, as we don't know how to do the proper flush
 171          * for the time being. Invalidations will remain global if
 172          * used on hash. Note that we can't drop 'copros' either, as
 173          * it could make some invalidations local with no flush
 174          * in-between.
 175          */
 176         if (radix_enabled()) {
 177                 flush_all_mm(mm);
 178
 179                 c = atomic_dec_if_positive(&mm->context.copros);
 180                 /* Detect imbalance between add and remove */
 181                 WARN_ON(c < 0);
 182
 183                 if (c == 0)
 184                         dec_mm_active_cpus(mm);
 185         }
 186 }
 187 #else
 188 static inline void inc_mm_active_cpus(struct mm_struct *mm) { }
 189 static inline void dec_mm_active_cpus(struct mm_struct *mm) { }
 190 static inline void mm_context_add_copro(struct mm_struct *mm) { }
 191 static inline void mm_context_remove_copro(struct mm_struct *mm) { }
 192 #endif
 193
 194
 195 extern void switch_mm_irqs_off(struct mm_struct *prev, struct mm_struct *next,
 196                                struct task_struct *tsk);
 197
 198 static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
 199                              struct task_struct *tsk)
 200 {
 201         unsigned long flags;
 202
 203         local_irq_save(flags);
 204         switch_mm_irqs_off(prev, next, tsk);
 205         local_irq_restore(flags);
 206 }
 207 #define switch_mm_irqs_off switch_mm_irqs_off
 208
 209
 210 #define deactivate_mm(tsk,mm)   do { } while (0)
 211
 212 /*
 213  * After we have set current->mm to a new value, this activates
 214  * the context for the new mm so we see the new mappings.
 215  */
 216 static inline void activate_mm(struct mm_struct *prev, struct mm_struct *next)
 217 {
 218         switch_mm(prev, next, current);
 219 }
 220
 221 /* We don't currently use enter_lazy_tlb() for anything */
 222 static inline void enter_lazy_tlb(struct mm_struct *mm,
 223                                   struct task_struct *tsk)
 224 {
 225         /* 64-bit Book3E keeps track of current PGD in the PACA */
 226 #ifdef CONFIG_PPC_BOOK3E_64
 227         get_paca()->pgd = NULL;
 228 #endif
 229 }
 230
 231 #ifdef CONFIG_PPC_BOOK3E_64
 232 static inline void arch_exit_mmap(struct mm_struct *mm)
 233 {
 234 }
 235 #else
 236 extern void arch_exit_mmap(struct mm_struct *mm);
 237 #endif
 238
 239 static inline void arch_unmap(struct mm_struct *mm,
 240                               struct vm_area_struct *vma,
 241                               unsigned long start, unsigned long end)
 242 {
 243         if (start <= mm->context.vdso_base && mm->context.vdso_base < end)
 244                 mm->context.vdso_base = 0;
 245 }
 246
 247 static inline void arch_bprm_mm_init(struct mm_struct *mm,
 248                                      struct vm_area_struct *vma)
 249 {
 250 }
 251
 252 #ifdef CONFIG_PPC_MEM_KEYS
 253 bool arch_vma_access_permitted(struct vm_area_struct *vma, bool write,
 254                                bool execute, bool foreign);
 255 void arch_dup_pkeys(struct mm_struct *oldmm, struct mm_struct *mm);
 256 #else /* CONFIG_PPC_MEM_KEYS */
 257 static inline bool arch_vma_access_permitted(struct vm_area_struct *vma,
 258                 bool write, bool execute, bool foreign)
 259 {
 260         /* by default, allow everything */
 261         return true;
 262 }
 263
 264 #define pkey_mm_init(mm)
 265 #define thread_pkey_regs_save(thread)
 266 #define thread_pkey_regs_restore(new_thread, old_thread)
 267 #define thread_pkey_regs_init(thread)
 268 #define arch_dup_pkeys(oldmm, mm)
 269
 270 static inline u64 pte_to_hpte_pkey_bits(u64 pteflags)
 271 {
 272         return 0x0UL;
 273 }
 274
 275 #endif /* CONFIG_PPC_MEM_KEYS */
 276
 277 static inline int arch_dup_mmap(struct mm_struct *oldmm,
 278                                 struct mm_struct *mm)
 279 {
 280         arch_dup_pkeys(oldmm, mm);
 281         return 0;
 282 }
 283
 284 #endif /* __KERNEL__ */
 285 #endif /* __ASM_POWERPC_MMU_CONTEXT_H */