LXR linux/arch/powerpc/include/asm/mmu

   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
  18extern int init_new_context(struct task_struct *tsk, struct mm_struct *mm);
  19#define destroy_context destroy_context
  20extern void destroy_context(struct mm_struct *mm);
  21#ifdef CONFIG_SPAPR_TCE_IOMMU
  22struct mm_iommu_table_group_mem_t;
  23
  24extern int isolate_lru_page(struct page *page); /* from internal.h */
  25extern bool mm_iommu_preregistered(struct mm_struct *mm);
  26extern long mm_iommu_new(struct mm_struct *mm,
  27                unsigned long ua, unsigned long entries,
  28                struct mm_iommu_table_group_mem_t **pmem);
  29extern 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);
  32extern long mm_iommu_put(struct mm_struct *mm,
  33                struct mm_iommu_table_group_mem_t *mem);
  34extern void mm_iommu_init(struct mm_struct *mm);
  35extern void mm_iommu_cleanup(struct mm_struct *mm);
  36extern struct mm_iommu_table_group_mem_t *mm_iommu_lookup(struct mm_struct *mm,
  37                unsigned long ua, unsigned long size);
  38extern struct mm_iommu_table_group_mem_t *mm_iommu_lookup_rm(
  39                struct mm_struct *mm, unsigned long ua, unsigned long size);
  40extern struct mm_iommu_table_group_mem_t *mm_iommu_get(struct mm_struct *mm,
  41                unsigned long ua, unsigned long entries);
  42extern long mm_iommu_ua_to_hpa(struct mm_iommu_table_group_mem_t *mem,
  43                unsigned long ua, unsigned int pageshift, unsigned long *hpa);
  44extern 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);
  46extern void mm_iommu_ua_mark_dirty_rm(struct mm_struct *mm, unsigned long ua);
  47extern bool mm_iommu_is_devmem(struct mm_struct *mm, unsigned long hpa,
  48                unsigned int pageshift, unsigned long *size);
  49extern long mm_iommu_mapped_inc(struct mm_iommu_table_group_mem_t *mem);
  50extern void mm_iommu_mapped_dec(struct mm_iommu_table_group_mem_t *mem);
  51#else
  52static 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}
  57static inline void mm_iommu_init(struct mm_struct *mm) { }
  58#endif
  59extern void switch_slb(struct task_struct *tsk, struct mm_struct *mm);
  60extern void set_context(unsigned long id, pgd_t *pgd);
  61
  62#ifdef CONFIG_PPC_BOOK3S_64
  63extern void radix__switch_mmu_context(struct mm_struct *prev,
  64                                      struct mm_struct *next);
  65static 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
  74extern int hash__alloc_context_id(void);
  75extern void hash__reserve_context_id(int id);
  76extern void __destroy_context(int context_id);
  77static inline void mmu_context_init(void) { }
  78
  79static 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
  95static 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
 106extern void switch_mmu_context(struct mm_struct *prev, struct mm_struct *next,
 107                               struct task_struct *tsk);
 108extern unsigned long __init_new_context(void);
 109extern void __destroy_context(unsigned long context_id);
 110extern void mmu_context_init(void);
 111static 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
 119static 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)
 126extern void radix_kvm_prefetch_workaround(struct mm_struct *mm);
 127#else
 128static inline void radix_kvm_prefetch_workaround(struct mm_struct *mm) { }
 129#endif
 130
 131extern void switch_cop(struct mm_struct *next);
 132extern int use_cop(unsigned long acop, struct mm_struct *mm);
 133extern void drop_cop(unsigned long acop, struct mm_struct *mm);
 134
 135#ifdef CONFIG_PPC_BOOK3S_64
 136static inline void inc_mm_active_cpus(struct mm_struct *mm)
 137{
 138        atomic_inc(&mm->context.active_cpus);
 139}
 140
 141static inline void dec_mm_active_cpus(struct mm_struct *mm)
 142{
 143        atomic_dec(&mm->context.active_cpus);
 144}
 145
 146static 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
 157static 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 */
 202static 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
 208static 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
 219static inline void inc_mm_active_cpus(struct mm_struct *mm) { }
 220static inline void dec_mm_active_cpus(struct mm_struct *mm) { }
 221static inline void mm_context_add_copro(struct mm_struct *mm) { }
 222static inline void mm_context_remove_copro(struct mm_struct *mm) { }
 223#endif
 224
 225
 226extern void switch_mm_irqs_off(struct mm_struct *prev, struct mm_struct *next,
 227                               struct task_struct *tsk);
 228
 229static 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
 245static 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
 253static 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
 261extern void arch_exit_mmap(struct mm_struct *mm);
 262
 263static 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
 273bool arch_vma_access_permitted(struct vm_area_struct *vma, bool write,
 274                               bool execute, bool foreign);
 275void arch_dup_pkeys(struct mm_struct *oldmm, struct mm_struct *mm);
 276#else /* CONFIG_PPC_MEM_KEYS */
 277static 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
 287static 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
 294static 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