arch/x86/include/asm/mmu.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _ASM_X86_MMU_H
   3 #define _ASM_X86_MMU_H
   4
   5 #include <linux/spinlock.h>
   6 #include <linux/rwsem.h>
   7 #include <linux/mutex.h>
   8 #include <linux/atomic.h>
   9
  10 /*
  11  * x86 has arch-specific MMU state beyond what lives in mm_struct.
  12  */
  13 typedef struct {
  14         /*
  15          * ctx_id uniquely identifies this mm_struct.  A ctx_id will never
  16          * be reused, and zero is not a valid ctx_id.
  17          */
  18         u64 ctx_id;
  19
  20         /*
  21          * Any code that needs to do any sort of TLB flushing for this
  22          * mm will first make its changes to the page tables, then
  23          * increment tlb_gen, then flush.  This lets the low-level
  24          * flushing code keep track of what needs flushing.
  25          *
  26          * This is not used on Xen PV.
  27          */
  28         atomic64_t tlb_gen;
  29
  30 #ifdef CONFIG_MODIFY_LDT_SYSCALL
  31         struct rw_semaphore     ldt_usr_sem;
  32         struct ldt_struct       *ldt;
  33 #endif
  34
  35 #ifdef CONFIG_X86_64
  36         /* True if mm supports a task running in 32 bit compatibility mode. */
  37         unsigned short ia32_compat;
  38 #endif
  39
  40         struct mutex lock;
  41         void __user *vdso;                      /* vdso base address */
  42         const struct vdso_image *vdso_image;    /* vdso image in use */
  43
  44         atomic_t perf_rdpmc_allowed;    /* nonzero if rdpmc is allowed */
  45 #ifdef CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS
  46         /*
  47          * One bit per protection key says whether userspace can
  48          * use it or not.  protected by mmap_sem.
  49          */
  50         u16 pkey_allocation_map;
  51         s16 execute_only_pkey;
  52 #endif
  53 } mm_context_t;
  54
  55 #define INIT_MM_CONTEXT(mm)                                             \
  56         .context = {                                                    \
  57                 .ctx_id = 1,                                            \
  58                 .lock = __MUTEX_INITIALIZER(mm.context.lock),           \
  59         }
  60
  61 void leave_mm(int cpu);
  62
  63 #endif /* _ASM_X86_MMU_H */