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 #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 bool mm_iommu_preregistered(struct mm_struct *mm);
  25 extern long mm_iommu_new(struct mm_struct *mm,
  26                 unsigned long ua, unsigned long entries,
  27                 struct mm_iommu_table_group_mem_t **pmem);
  28 extern long mm_iommu_newdev(struct mm_struct *mm, unsigned long ua,
  29                 unsigned long entries, unsigned long dev_hpa,
  30                 struct mm_iommu_table_group_mem_t **pmem);
  31 extern long mm_iommu_put(struct mm_struct *mm,
  32                 struct mm_iommu_table_group_mem_t *mem);
  33 extern void mm_iommu_init(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_get(struct mm_struct *mm,
  37                 unsigned long ua, unsigned long entries);
  38 extern long mm_iommu_ua_to_hpa(struct mm_iommu_table_group_mem_t *mem,
  39                 unsigned long ua, unsigned int pageshift, unsigned long *hpa);
  40 extern bool mm_iommu_is_devmem(struct mm_struct *mm, unsigned long hpa,
  41                 unsigned int pageshift, unsigned long *size);
  42 extern long mm_iommu_mapped_inc(struct mm_iommu_table_group_mem_t *mem);
  43 extern void mm_iommu_mapped_dec(struct mm_iommu_table_group_mem_t *mem);
  44 #else
  45 static inline bool mm_iommu_is_devmem(struct mm_struct *mm, unsigned long hpa,
  46                 unsigned int pageshift, unsigned long *size)
  47 {
  48         return false;
  49 }
  50 static inline void mm_iommu_init(struct mm_struct *mm) { }
  51 #endif
  52 extern void switch_slb(struct task_struct *tsk, struct mm_struct *mm);
  53
  54 #ifdef CONFIG_PPC_BOOK3S_64
  55 extern void radix__switch_mmu_context(struct mm_struct *prev,
  56                                       struct mm_struct *next);
  57 static inline void switch_mmu_context(struct mm_struct *prev,
  58                                       struct mm_struct *next,
  59                                       struct task_struct *tsk)
  60 {
  61         if (radix_enabled())
  62                 return radix__switch_mmu_context(prev, next);
  63         return switch_slb(tsk, next);
  64 }
  65
  66 extern int hash__alloc_context_id(void);
  67 void __init hash__reserve_context_id(int id);
  68 extern void __destroy_context(int context_id);
  69 static inline void mmu_context_init(void) { }
  70
  71 #ifdef CONFIG_PPC_64S_HASH_MMU
  72 static inline int alloc_extended_context(struct mm_struct *mm,
  73                                          unsigned long ea)
  74 {
  75         int context_id;
  76
  77         int index = ea >> MAX_EA_BITS_PER_CONTEXT;
  78
  79         context_id = hash__alloc_context_id();
  80         if (context_id < 0)
  81                 return context_id;
  82
  83         VM_WARN_ON(mm->context.extended_id[index]);
  84         mm->context.extended_id[index] = context_id;
  85         return context_id;
  86 }
  87
  88 static inline bool need_extra_context(struct mm_struct *mm, unsigned long ea)
  89 {
  90         int context_id;
  91
  92         context_id = get_user_context(&mm->context, ea);
  93         if (!context_id)
  94                 return true;
  95         return false;
  96 }
  97 #endif
  98
  99 #else
 100 extern void switch_mmu_context(struct mm_struct *prev, struct mm_struct *next,
 101                                struct task_struct *tsk);
 102 extern unsigned long __init_new_context(void);
 103 extern void __destroy_context(unsigned long context_id);
 104 extern void mmu_context_init(void);
 105 static inline int alloc_extended_context(struct mm_struct *mm,
 106                                          unsigned long ea)
 107 {
 108         /* non book3s_64 should never find this called */
 109         WARN_ON(1);
 110         return -ENOMEM;
 111 }
 112
 113 static inline bool need_extra_context(struct mm_struct *mm, unsigned long ea)
 114 {
 115         return false;
 116 }
 117 #endif
 118
 119 #ifdef CONFIG_PPC_BOOK3S_64
 120 static inline void inc_mm_active_cpus(struct mm_struct *mm)
 121 {
 122         atomic_inc(&mm->context.active_cpus);
 123 }
 124
 125 static inline void dec_mm_active_cpus(struct mm_struct *mm)
 126 {
 127         VM_WARN_ON_ONCE(atomic_read(&mm->context.active_cpus) <= 0);
 128         atomic_dec(&mm->context.active_cpus);
 129 }
 130
 131 static inline void mm_context_add_copro(struct mm_struct *mm)
 132 {
 133         /*
 134          * If any copro is in use, increment the active CPU count
 135          * in order to force TLB invalidations to be global as to
 136          * propagate to the Nest MMU.
 137          */
 138         if (atomic_inc_return(&mm->context.copros) == 1)
 139                 inc_mm_active_cpus(mm);
 140 }
 141
 142 static inline void mm_context_remove_copro(struct mm_struct *mm)
 143 {
 144         int c;
 145
 146         /*
 147          * When removing the last copro, we need to broadcast a global
 148          * flush of the full mm, as the next TLBI may be local and the
 149          * nMMU and/or PSL need to be cleaned up.
 150          *
 151          * Both the 'copros' and 'active_cpus' counts are looked at in
 152          * radix__flush_all_mm() to determine the scope (local/global)
 153          * of the TLBIs, so we need to flush first before decrementing
 154          * 'copros'. If this API is used by several callers for the
 155          * same context, it can lead to over-flushing. It's hopefully
 156          * not common enough to be a problem.
 157          *
 158          * Skip on hash, as we don't know how to do the proper flush
 159          * for the time being. Invalidations will remain global if
 160          * used on hash. Note that we can't drop 'copros' either, as
 161          * it could make some invalidations local with no flush
 162          * in-between.
 163          */
 164         if (radix_enabled()) {
 165                 radix__flush_all_mm(mm);
 166
 167                 c = atomic_dec_if_positive(&mm->context.copros);
 168                 /* Detect imbalance between add and remove */
 169                 WARN_ON(c < 0);
 170
 171                 if (c == 0)
 172                         dec_mm_active_cpus(mm);
 173         }
 174 }
 175
 176 /*
 177  * vas_windows counter shows number of open windows in the mm
 178  * context. During context switch, use this counter to clear the
 179  * foreign real address mapping (CP_ABORT) for the thread / process
 180  * that intend to use COPY/PASTE. When a process closes all windows,
 181  * disable CP_ABORT which is expensive to run.
 182  *
 183  * For user context, register a copro so that TLBIs are seen by the
 184  * nest MMU. mm_context_add/remove_vas_window() are used only for user
 185  * space windows.
 186  */
 187 static inline void mm_context_add_vas_window(struct mm_struct *mm)
 188 {
 189         atomic_inc(&mm->context.vas_windows);
 190         mm_context_add_copro(mm);
 191 }
 192
 193 static inline void mm_context_remove_vas_window(struct mm_struct *mm)
 194 {
 195         int v;
 196
 197         mm_context_remove_copro(mm);
 198         v = atomic_dec_if_positive(&mm->context.vas_windows);
 199
 200         /* Detect imbalance between add and remove */
 201         WARN_ON(v < 0);
 202 }
 203 #else
 204 static inline void inc_mm_active_cpus(struct mm_struct *mm) { }
 205 static inline void dec_mm_active_cpus(struct mm_struct *mm) { }
 206 static inline void mm_context_add_copro(struct mm_struct *mm) { }
 207 static inline void mm_context_remove_copro(struct mm_struct *mm) { }
 208 #endif
 209
 210 #if defined(CONFIG_KVM_BOOK3S_HV_POSSIBLE) && defined(CONFIG_PPC_RADIX_MMU)
 211 void do_h_rpt_invalidate_prt(unsigned long pid, unsigned long lpid,
 212                              unsigned long type, unsigned long pg_sizes,
 213                              unsigned long start, unsigned long end);
 214 #else
 215 static inline void do_h_rpt_invalidate_prt(unsigned long pid,
 216                                            unsigned long lpid,
 217                                            unsigned long type,
 218                                            unsigned long pg_sizes,
 219                                            unsigned long start,
 220                                            unsigned long end) { }
 221 #endif
 222
 223 extern void switch_mm_irqs_off(struct mm_struct *prev, struct mm_struct *next,
 224                                struct task_struct *tsk);
 225
 226 static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
 227                              struct task_struct *tsk)
 228 {
 229         unsigned long flags;
 230
 231         local_irq_save(flags);
 232         switch_mm_irqs_off(prev, next, tsk);
 233         local_irq_restore(flags);
 234 }
 235 #define switch_mm_irqs_off switch_mm_irqs_off
 236
 237 /*
 238  * After we have set current->mm to a new value, this activates
 239  * the context for the new mm so we see the new mappings.
 240  */
 241 #define activate_mm activate_mm
 242 static inline void activate_mm(struct mm_struct *prev, struct mm_struct *next)
 243 {
 244         switch_mm_irqs_off(prev, next, current);
 245 }
 246
 247 /* We don't currently use enter_lazy_tlb() for anything */
 248 #ifdef CONFIG_PPC_BOOK3E_64
 249 #define enter_lazy_tlb enter_lazy_tlb
 250 static inline void enter_lazy_tlb(struct mm_struct *mm,
 251                                   struct task_struct *tsk)
 252 {
 253         /* 64-bit Book3E keeps track of current PGD in the PACA */
 254         get_paca()->pgd = NULL;
 255 }
 256 #endif
 257
 258 extern void arch_exit_mmap(struct mm_struct *mm);
 259
 260 #ifdef CONFIG_PPC_MEM_KEYS
 261 bool arch_vma_access_permitted(struct vm_area_struct *vma, bool write,
 262                                bool execute, bool foreign);
 263 void arch_dup_pkeys(struct mm_struct *oldmm, struct mm_struct *mm);
 264 #else /* CONFIG_PPC_MEM_KEYS */
 265 static inline bool arch_vma_access_permitted(struct vm_area_struct *vma,
 266                 bool write, bool execute, bool foreign)
 267 {
 268         /* by default, allow everything */
 269         return true;
 270 }
 271
 272 #define pkey_mm_init(mm)
 273 #define arch_dup_pkeys(oldmm, mm)
 274
 275 static inline u64 pte_to_hpte_pkey_bits(u64 pteflags, unsigned long flags)
 276 {
 277         return 0x0UL;
 278 }
 279
 280 #endif /* CONFIG_PPC_MEM_KEYS */
 281
 282 static inline int arch_dup_mmap(struct mm_struct *oldmm,
 283                                 struct mm_struct *mm)
 284 {
 285         arch_dup_pkeys(oldmm, mm);
 286         return 0;
 287 }
 288
 289 #include <asm-generic/mmu_context.h>
 290
 291 #endif /* __KERNEL__ */
 292 #endif /* __ASM_POWERPC_MMU_CONTEXT_H */