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