arch/x86/include/asm/tlbflush.h

   1 #ifndef _ASM_X86_TLBFLUSH_H
   2 #define _ASM_X86_TLBFLUSH_H
   3
   4 #include <linux/mm.h>
   5 #include <linux/sched.h>
   6
   7 #include <asm/processor.h>
   8 #include <asm/cpufeature.h>
   9 #include <asm/special_insns.h>
  10
  11 static inline void __invpcid(unsigned long pcid, unsigned long addr,
  12                              unsigned long type)
  13 {
  14         struct { u64 d[2]; } desc = { { pcid, addr } };
  15
  16         /*
  17          * The memory clobber is because the whole point is to invalidate
  18          * stale TLB entries and, especially if we're flushing global
  19          * mappings, we don't want the compiler to reorder any subsequent
  20          * memory accesses before the TLB flush.
  21          *
  22          * The hex opcode is invpcid (%ecx), %eax in 32-bit mode and
  23          * invpcid (%rcx), %rax in long mode.
  24          */
  25         asm volatile (".byte 0x66, 0x0f, 0x38, 0x82, 0x01"
  26                       : : "m" (desc), "a" (type), "c" (&desc) : "memory");
  27 }
  28
  29 #define INVPCID_TYPE_INDIV_ADDR         0
  30 #define INVPCID_TYPE_SINGLE_CTXT        1
  31 #define INVPCID_TYPE_ALL_INCL_GLOBAL    2
  32 #define INVPCID_TYPE_ALL_NON_GLOBAL     3
  33
  34 /* Flush all mappings for a given pcid and addr, not including globals. */
  35 static inline void invpcid_flush_one(unsigned long pcid,
  36                                      unsigned long addr)
  37 {
  38         __invpcid(pcid, addr, INVPCID_TYPE_INDIV_ADDR);
  39 }
  40
  41 /* Flush all mappings for a given PCID, not including globals. */
  42 static inline void invpcid_flush_single_context(unsigned long pcid)
  43 {
  44         __invpcid(pcid, 0, INVPCID_TYPE_SINGLE_CTXT);
  45 }
  46
  47 /* Flush all mappings, including globals, for all PCIDs. */
  48 static inline void invpcid_flush_all(void)
  49 {
  50         __invpcid(0, 0, INVPCID_TYPE_ALL_INCL_GLOBAL);
  51 }
  52
  53 /* Flush all mappings for all PCIDs except globals. */
  54 static inline void invpcid_flush_all_nonglobals(void)
  55 {
  56         __invpcid(0, 0, INVPCID_TYPE_ALL_NON_GLOBAL);
  57 }
  58
  59 #ifdef CONFIG_PARAVIRT
  60 #include <asm/paravirt.h>
  61 #else
  62 #define __flush_tlb() __native_flush_tlb()
  63 #define __flush_tlb_global() __native_flush_tlb_global()
  64 #define __flush_tlb_single(addr) __native_flush_tlb_single(addr)
  65 #endif
  66
  67 struct tlb_state {
  68 #ifdef CONFIG_SMP
  69         struct mm_struct *active_mm;
  70         int state;
  71 #endif
  72
  73         /*
  74          * Access to this CR4 shadow and to H/W CR4 is protected by
  75          * disabling interrupts when modifying either one.
  76          */
  77         unsigned long cr4;
  78 };
  79 DECLARE_PER_CPU_SHARED_ALIGNED(struct tlb_state, cpu_tlbstate);
  80
  81 /* Initialize cr4 shadow for this CPU. */
  82 static inline void cr4_init_shadow(void)
  83 {
  84         this_cpu_write(cpu_tlbstate.cr4, __read_cr4());
  85 }
  86
  87 /* Set in this cpu's CR4. */
  88 static inline void cr4_set_bits(unsigned long mask)
  89 {
  90         unsigned long cr4;
  91
  92         cr4 = this_cpu_read(cpu_tlbstate.cr4);
  93         if ((cr4 | mask) != cr4) {
  94                 cr4 |= mask;
  95                 this_cpu_write(cpu_tlbstate.cr4, cr4);
  96                 __write_cr4(cr4);
  97         }
  98 }
  99
 100 /* Clear in this cpu's CR4. */
 101 static inline void cr4_clear_bits(unsigned long mask)
 102 {
 103         unsigned long cr4;
 104
 105         cr4 = this_cpu_read(cpu_tlbstate.cr4);
 106         if ((cr4 & ~mask) != cr4) {
 107                 cr4 &= ~mask;
 108                 this_cpu_write(cpu_tlbstate.cr4, cr4);
 109                 __write_cr4(cr4);
 110         }
 111 }
 112
 113 /* Read the CR4 shadow. */
 114 static inline unsigned long cr4_read_shadow(void)
 115 {
 116         return this_cpu_read(cpu_tlbstate.cr4);
 117 }
 118
 119 /*
 120  * Save some of cr4 feature set we're using (e.g.  Pentium 4MB
 121  * enable and PPro Global page enable), so that any CPU's that boot
 122  * up after us can get the correct flags.  This should only be used
 123  * during boot on the boot cpu.
 124  */
 125 extern unsigned long mmu_cr4_features;
 126 extern u32 *trampoline_cr4_features;
 127
 128 static inline void cr4_set_bits_and_update_boot(unsigned long mask)
 129 {
 130         mmu_cr4_features |= mask;
 131         if (trampoline_cr4_features)
 132                 *trampoline_cr4_features = mmu_cr4_features;
 133         cr4_set_bits(mask);
 134 }
 135
 136 static inline void __native_flush_tlb(void)
 137 {
 138         /*
 139          * If current->mm == NULL then we borrow a mm which may change during a
 140          * task switch and therefore we must not be preempted while we write CR3
 141          * back:
 142          */
 143         preempt_disable();
 144         native_write_cr3(native_read_cr3());
 145         preempt_enable();
 146 }
 147
 148 static inline void __native_flush_tlb_global_irq_disabled(void)
 149 {
 150         unsigned long cr4;
 151
 152         cr4 = this_cpu_read(cpu_tlbstate.cr4);
 153         /* clear PGE */
 154         native_write_cr4(cr4 & ~X86_CR4_PGE);
 155         /* write old PGE again and flush TLBs */
 156         native_write_cr4(cr4);
 157 }
 158
 159 static inline void __native_flush_tlb_global(void)
 160 {
 161         unsigned long flags;
 162
 163         if (static_cpu_has(X86_FEATURE_INVPCID)) {
 164                 /*
 165                  * Using INVPCID is considerably faster than a pair of writes
 166                  * to CR4 sandwiched inside an IRQ flag save/restore.
 167                  */
 168                 invpcid_flush_all();
 169                 return;
 170         }
 171
 172         /*
 173          * Read-modify-write to CR4 - protect it from preemption and
 174          * from interrupts. (Use the raw variant because this code can
 175          * be called from deep inside debugging code.)
 176          */
 177         raw_local_irq_save(flags);
 178
 179         __native_flush_tlb_global_irq_disabled();
 180
 181         raw_local_irq_restore(flags);
 182 }
 183
 184 static inline void __native_flush_tlb_single(unsigned long addr)
 185 {
 186         asm volatile("invlpg (%0)" ::"r" (addr) : "memory");
 187 }
 188
 189 static inline void __flush_tlb_all(void)
 190 {
 191         if (boot_cpu_has(X86_FEATURE_PGE))
 192                 __flush_tlb_global();
 193         else
 194                 __flush_tlb();
 195 }
 196
 197 static inline void __flush_tlb_one(unsigned long addr)
 198 {
 199         count_vm_tlb_event(NR_TLB_LOCAL_FLUSH_ONE);
 200         __flush_tlb_single(addr);
 201 }
 202
 203 #define TLB_FLUSH_ALL   -1UL
 204
 205 /*
 206  * TLB flushing:
 207  *
 208  *  - flush_tlb() flushes the current mm struct TLBs
 209  *  - flush_tlb_all() flushes all processes TLBs
 210  *  - flush_tlb_mm(mm) flushes the specified mm context TLB's
 211  *  - flush_tlb_page(vma, vmaddr) flushes one page
 212  *  - flush_tlb_range(vma, start, end) flushes a range of pages
 213  *  - flush_tlb_kernel_range(start, end) flushes a range of kernel pages
 214  *  - flush_tlb_others(cpumask, mm, start, end) flushes TLBs on other cpus
 215  *
 216  * ..but the i386 has somewhat limited tlb flushing capabilities,
 217  * and page-granular flushes are available only on i486 and up.
 218  */
 219
 220 #ifndef CONFIG_SMP
 221
 222 /* "_up" is for UniProcessor.
 223  *
 224  * This is a helper for other header functions.  *Not* intended to be called
 225  * directly.  All global TLB flushes need to either call this, or to bump the
 226  * vm statistics themselves.
 227  */
 228 static inline void __flush_tlb_up(void)
 229 {
 230         count_vm_tlb_event(NR_TLB_LOCAL_FLUSH_ALL);
 231         __flush_tlb();
 232 }
 233
 234 static inline void flush_tlb_all(void)
 235 {
 236         count_vm_tlb_event(NR_TLB_LOCAL_FLUSH_ALL);
 237         __flush_tlb_all();
 238 }
 239
 240 static inline void flush_tlb(void)
 241 {
 242         __flush_tlb_up();
 243 }
 244
 245 static inline void local_flush_tlb(void)
 246 {
 247         __flush_tlb_up();
 248 }
 249
 250 static inline void flush_tlb_mm(struct mm_struct *mm)
 251 {
 252         if (mm == current->active_mm)
 253                 __flush_tlb_up();
 254 }
 255
 256 static inline void flush_tlb_page(struct vm_area_struct *vma,
 257                                   unsigned long addr)
 258 {
 259         if (vma->vm_mm == current->active_mm)
 260                 __flush_tlb_one(addr);
 261 }
 262
 263 static inline void flush_tlb_range(struct vm_area_struct *vma,
 264                                    unsigned long start, unsigned long end)
 265 {
 266         if (vma->vm_mm == current->active_mm)
 267                 __flush_tlb_up();
 268 }
 269
 270 static inline void flush_tlb_mm_range(struct mm_struct *mm,
 271            unsigned long start, unsigned long end, unsigned long vmflag)
 272 {
 273         if (mm == current->active_mm)
 274                 __flush_tlb_up();
 275 }
 276
 277 static inline void native_flush_tlb_others(const struct cpumask *cpumask,
 278                                            struct mm_struct *mm,
 279                                            unsigned long start,
 280                                            unsigned long end)
 281 {
 282 }
 283
 284 static inline void reset_lazy_tlbstate(void)
 285 {
 286 }
 287
 288 static inline void flush_tlb_kernel_range(unsigned long start,
 289                                           unsigned long end)
 290 {
 291         flush_tlb_all();
 292 }
 293
 294 #else  /* SMP */
 295
 296 #include <asm/smp.h>
 297
 298 #define local_flush_tlb() __flush_tlb()
 299
 300 #define flush_tlb_mm(mm)        flush_tlb_mm_range(mm, 0UL, TLB_FLUSH_ALL, 0UL)
 301
 302 #define flush_tlb_range(vma, start, end)        \
 303                 flush_tlb_mm_range(vma->vm_mm, start, end, vma->vm_flags)
 304
 305 extern void flush_tlb_all(void);
 306 extern void flush_tlb_current_task(void);
 307 extern void flush_tlb_page(struct vm_area_struct *, unsigned long);
 308 extern void flush_tlb_mm_range(struct mm_struct *mm, unsigned long start,
 309                                 unsigned long end, unsigned long vmflag);
 310 extern void flush_tlb_kernel_range(unsigned long start, unsigned long end);
 311
 312 #define flush_tlb()     flush_tlb_current_task()
 313
 314 void native_flush_tlb_others(const struct cpumask *cpumask,
 315                                 struct mm_struct *mm,
 316                                 unsigned long start, unsigned long end);
 317
 318 #define TLBSTATE_OK     1
 319 #define TLBSTATE_LAZY   2
 320
 321 static inline void reset_lazy_tlbstate(void)
 322 {
 323         this_cpu_write(cpu_tlbstate.state, 0);
 324         this_cpu_write(cpu_tlbstate.active_mm, &init_mm);
 325 }
 326
 327 #endif  /* SMP */
 328
 329 #ifndef CONFIG_PARAVIRT
 330 #define flush_tlb_others(mask, mm, start, end)  \
 331         native_flush_tlb_others(mask, mm, start, end)
 332 #endif
 333
 334 #endif /* _ASM_X86_TLBFLUSH_H */