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 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 #else
 189 static inline void inc_mm_active_cpus(struct mm_struct *mm) { }
 190 static inline void dec_mm_active_cpus(struct mm_struct *mm) { }
 191 static inline void mm_context_add_copro(struct mm_struct *mm) { }
 192 static inline void mm_context_remove_copro(struct mm_struct *mm) { }
 193 #endif
 194
 195
 196 extern void switch_mm_irqs_off(struct mm_struct *prev, struct mm_struct *next,
 197                                struct task_struct *tsk);
 198
 199 static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
 200                              struct task_struct *tsk)
 201 {
 202         unsigned long flags;
 203
 204         local_irq_save(flags);
 205         switch_mm_irqs_off(prev, next, tsk);
 206         local_irq_restore(flags);
 207 }
 208 #define switch_mm_irqs_off switch_mm_irqs_off
 209
 210
 211 #define deactivate_mm(tsk,mm)   do { } while (0)
 212
 213 /*
 214  * After we have set current->mm to a new value, this activates
 215  * the context for the new mm so we see the new mappings.
 216  */
 217 static inline void activate_mm(struct mm_struct *prev, struct mm_struct *next)
 218 {
 219         switch_mm(prev, next, current);
 220 }
 221
 222 /* We don't currently use enter_lazy_tlb() for anything */
 223 static inline void enter_lazy_tlb(struct mm_struct *mm,
 224                                   struct task_struct *tsk)
 225 {
 226         /* 64-bit Book3E keeps track of current PGD in the PACA */
 227 #ifdef CONFIG_PPC_BOOK3E_64
 228         get_paca()->pgd = NULL;
 229 #endif
 230 }
 231
 232 extern void arch_exit_mmap(struct mm_struct *mm);
 233
 234 static inline void arch_unmap(struct mm_struct *mm,
 235                               unsigned long start, unsigned long end)
 236 {
 237         if (start <= mm->context.vdso_base && mm->context.vdso_base < end)
 238                 mm->context.vdso_base = 0;
 239 }
 240
 241 static inline void arch_bprm_mm_init(struct mm_struct *mm,
 242                                      struct vm_area_struct *vma)
 243 {
 244 }
 245
 246 #ifdef CONFIG_PPC_MEM_KEYS
 247 bool arch_vma_access_permitted(struct vm_area_struct *vma, bool write,
 248                                bool execute, bool foreign);
 249 void arch_dup_pkeys(struct mm_struct *oldmm, struct mm_struct *mm);
 250 #else /* CONFIG_PPC_MEM_KEYS */
 251 static inline bool arch_vma_access_permitted(struct vm_area_struct *vma,
 252                 bool write, bool execute, bool foreign)
 253 {
 254         /* by default, allow everything */
 255         return true;
 256 }
 257
 258 #define pkey_mm_init(mm)
 259 #define thread_pkey_regs_save(thread)
 260 #define thread_pkey_regs_restore(new_thread, old_thread)
 261 #define thread_pkey_regs_init(thread)
 262 #define arch_dup_pkeys(oldmm, mm)
 263
 264 static inline u64 pte_to_hpte_pkey_bits(u64 pteflags)
 265 {
 266         return 0x0UL;
 267 }
 268
 269 #endif /* CONFIG_PPC_MEM_KEYS */
 270
 271 static inline int arch_dup_mmap(struct mm_struct *oldmm,
 272                                 struct mm_struct *mm)
 273 {
 274         arch_dup_pkeys(oldmm, mm);
 275         return 0;
 276 }
 277
 278 #endif /* __KERNEL__ */
 279 #endif /* __ASM_POWERPC_MMU_CONTEXT_H */