arch/x86/include/asm/mpx.h

   1 #ifndef _ASM_X86_MPX_H
   2 #define _ASM_X86_MPX_H
   3
   4 #include <linux/types.h>
   5 #include <linux/mm_types.h>
   6
   7 #include <asm/ptrace.h>
   8 #include <asm/insn.h>
   9
  10 /*
  11  * NULL is theoretically a valid place to put the bounds
  12  * directory, so point this at an invalid address.
  13  */
  14 #define MPX_INVALID_BOUNDS_DIR  ((void __user *)-1)
  15 #define MPX_BNDCFG_ENABLE_FLAG  0x1
  16 #define MPX_BD_ENTRY_VALID_FLAG 0x1
  17
  18 /*
  19  * The upper 28 bits [47:20] of the virtual address in 64-bit
  20  * are used to index into bounds directory (BD).
  21  *
  22  * The directory is 2G (2^31) in size, and with 8-byte entries
  23  * it has 2^28 entries.
  24  */
  25 #define MPX_BD_SIZE_BYTES_64    (1UL<<31)
  26 #define MPX_BD_ENTRY_BYTES_64   8
  27 #define MPX_BD_NR_ENTRIES_64    (MPX_BD_SIZE_BYTES_64/MPX_BD_ENTRY_BYTES_64)
  28
  29 /*
  30  * The 32-bit directory is 4MB (2^22) in size, and with 4-byte
  31  * entries it has 2^20 entries.
  32  */
  33 #define MPX_BD_SIZE_BYTES_32    (1UL<<22)
  34 #define MPX_BD_ENTRY_BYTES_32   4
  35 #define MPX_BD_NR_ENTRIES_32    (MPX_BD_SIZE_BYTES_32/MPX_BD_ENTRY_BYTES_32)
  36
  37 /*
  38  * A 64-bit table is 4MB total in size, and an entry is
  39  * 4 64-bit pointers in size.
  40  */
  41 #define MPX_BT_SIZE_BYTES_64    (1UL<<22)
  42 #define MPX_BT_ENTRY_BYTES_64   32
  43 #define MPX_BT_NR_ENTRIES_64    (MPX_BT_SIZE_BYTES_64/MPX_BT_ENTRY_BYTES_64)
  44
  45 /*
  46  * A 32-bit table is 16kB total in size, and an entry is
  47  * 4 32-bit pointers in size.
  48  */
  49 #define MPX_BT_SIZE_BYTES_32    (1UL<<14)
  50 #define MPX_BT_ENTRY_BYTES_32   16
  51 #define MPX_BT_NR_ENTRIES_32    (MPX_BT_SIZE_BYTES_32/MPX_BT_ENTRY_BYTES_32)
  52
  53 #define MPX_BNDSTA_TAIL         2
  54 #define MPX_BNDCFG_TAIL         12
  55 #define MPX_BNDSTA_ADDR_MASK    (~((1UL<<MPX_BNDSTA_TAIL)-1))
  56 #define MPX_BNDCFG_ADDR_MASK    (~((1UL<<MPX_BNDCFG_TAIL)-1))
  57 #define MPX_BNDSTA_ERROR_CODE   0x3
  58
  59 #ifdef CONFIG_X86_INTEL_MPX
  60 siginfo_t *mpx_generate_siginfo(struct pt_regs *regs);
  61 int mpx_handle_bd_fault(void);
  62 static inline int kernel_managing_mpx_tables(struct mm_struct *mm)
  63 {
  64         return (mm->context.bd_addr != MPX_INVALID_BOUNDS_DIR);
  65 }
  66 static inline void mpx_mm_init(struct mm_struct *mm)
  67 {
  68         /*
  69          * NULL is theoretically a valid place to put the bounds
  70          * directory, so point this at an invalid address.
  71          */
  72         mm->context.bd_addr = MPX_INVALID_BOUNDS_DIR;
  73 }
  74 void mpx_notify_unmap(struct mm_struct *mm, struct vm_area_struct *vma,
  75                       unsigned long start, unsigned long end);
  76 #else
  77 static inline siginfo_t *mpx_generate_siginfo(struct pt_regs *regs)
  78 {
  79         return NULL;
  80 }
  81 static inline int mpx_handle_bd_fault(void)
  82 {
  83         return -EINVAL;
  84 }
  85 static inline int kernel_managing_mpx_tables(struct mm_struct *mm)
  86 {
  87         return 0;
  88 }
  89 static inline void mpx_mm_init(struct mm_struct *mm)
  90 {
  91 }
  92 static inline void mpx_notify_unmap(struct mm_struct *mm,
  93                                     struct vm_area_struct *vma,
  94                                     unsigned long start, unsigned long end)
  95 {
  96 }
  97 #endif /* CONFIG_X86_INTEL_MPX */
  98
  99 #endif /* _ASM_X86_MPX_H */