tools/testing/selftests/x86/mpx-hw.h

   1 #ifndef _MPX_HW_H
   2 #define _MPX_HW_H
   3
   4 #include <assert.h>
   5
   6 /* Describe the MPX Hardware Layout in here */
   7
   8 #define NR_MPX_BOUNDS_REGISTERS 4
   9
  10 #ifdef __i386__
  11
  12 #define MPX_BOUNDS_TABLE_ENTRY_SIZE_BYTES       16 /* 4 * 32-bits */
  13 #define MPX_BOUNDS_TABLE_SIZE_BYTES             (1ULL << 14) /* 16k */
  14 #define MPX_BOUNDS_DIR_ENTRY_SIZE_BYTES         4
  15 #define MPX_BOUNDS_DIR_SIZE_BYTES               (1ULL << 22) /* 4MB */
  16
  17 #define MPX_BOUNDS_TABLE_BOTTOM_BIT             2
  18 #define MPX_BOUNDS_TABLE_TOP_BIT                11
  19 #define MPX_BOUNDS_DIR_BOTTOM_BIT               12
  20 #define MPX_BOUNDS_DIR_TOP_BIT                  31
  21
  22 #else
  23
  24 /*
  25  * Linear Address of "pointer" (LAp)
  26  *   0 ->  2: ignored
  27  *   3 -> 19: index in to bounds table
  28  *  20 -> 47: index in to bounds directory
  29  *  48 -> 63: ignored
  30  */
  31
  32 #define MPX_BOUNDS_TABLE_ENTRY_SIZE_BYTES       32
  33 #define MPX_BOUNDS_TABLE_SIZE_BYTES             (1ULL << 22) /* 4MB */
  34 #define MPX_BOUNDS_DIR_ENTRY_SIZE_BYTES         8
  35 #define MPX_BOUNDS_DIR_SIZE_BYTES               (1ULL << 31) /* 2GB */
  36
  37 #define MPX_BOUNDS_TABLE_BOTTOM_BIT             3
  38 #define MPX_BOUNDS_TABLE_TOP_BIT                19
  39 #define MPX_BOUNDS_DIR_BOTTOM_BIT               20
  40 #define MPX_BOUNDS_DIR_TOP_BIT                  47
  41
  42 #endif
  43
  44 #define MPX_BOUNDS_DIR_NR_ENTRIES       \
  45         (MPX_BOUNDS_DIR_SIZE_BYTES/MPX_BOUNDS_DIR_ENTRY_SIZE_BYTES)
  46 #define MPX_BOUNDS_TABLE_NR_ENTRIES     \
  47         (MPX_BOUNDS_TABLE_SIZE_BYTES/MPX_BOUNDS_TABLE_ENTRY_SIZE_BYTES)
  48
  49 #define MPX_BOUNDS_TABLE_ENTRY_VALID_BIT        0x1
  50
  51 struct mpx_bd_entry {
  52         union {
  53                 char x[MPX_BOUNDS_DIR_ENTRY_SIZE_BYTES];
  54                 void *contents[1];
  55         };
  56 } __attribute__((packed));
  57
  58 struct mpx_bt_entry {
  59         union {
  60                 char x[MPX_BOUNDS_TABLE_ENTRY_SIZE_BYTES];
  61                 unsigned long contents[1];
  62         };
  63 } __attribute__((packed));
  64
  65 struct mpx_bounds_dir {
  66         struct mpx_bd_entry entries[MPX_BOUNDS_DIR_NR_ENTRIES];
  67 } __attribute__((packed));
  68
  69 struct mpx_bounds_table {
  70         struct mpx_bt_entry entries[MPX_BOUNDS_TABLE_NR_ENTRIES];
  71 } __attribute__((packed));
  72
  73 static inline unsigned long GET_BITS(unsigned long val, int bottombit, int topbit)
  74 {
  75         int total_nr_bits = topbit - bottombit;
  76         unsigned long mask = (1UL << total_nr_bits)-1;
  77         return (val >> bottombit) & mask;
  78 }
  79
  80 static inline unsigned long __vaddr_bounds_table_index(void *vaddr)
  81 {
  82         return GET_BITS((unsigned long)vaddr, MPX_BOUNDS_TABLE_BOTTOM_BIT,
  83                                               MPX_BOUNDS_TABLE_TOP_BIT);
  84 }
  85
  86 static inline unsigned long __vaddr_bounds_directory_index(void *vaddr)
  87 {
  88         return GET_BITS((unsigned long)vaddr, MPX_BOUNDS_DIR_BOTTOM_BIT,
  89                                               MPX_BOUNDS_DIR_TOP_BIT);
  90 }
  91
  92 static inline struct mpx_bd_entry *mpx_vaddr_to_bd_entry(void *vaddr,
  93                 struct mpx_bounds_dir *bounds_dir)
  94 {
  95         unsigned long index = __vaddr_bounds_directory_index(vaddr);
  96         return &bounds_dir->entries[index];
  97 }
  98
  99 static inline int bd_entry_valid(struct mpx_bd_entry *bounds_dir_entry)
 100 {
 101         unsigned long __bd_entry = (unsigned long)bounds_dir_entry->contents;
 102         return (__bd_entry & MPX_BOUNDS_TABLE_ENTRY_VALID_BIT);
 103 }
 104
 105 static inline struct mpx_bounds_table *
 106 __bd_entry_to_bounds_table(struct mpx_bd_entry *bounds_dir_entry)
 107 {
 108         unsigned long __bd_entry = (unsigned long)bounds_dir_entry->contents;
 109         assert(__bd_entry & MPX_BOUNDS_TABLE_ENTRY_VALID_BIT);
 110         __bd_entry &= ~MPX_BOUNDS_TABLE_ENTRY_VALID_BIT;
 111         return (struct mpx_bounds_table *)__bd_entry;
 112 }
 113
 114 static inline struct mpx_bt_entry *
 115 mpx_vaddr_to_bt_entry(void *vaddr, struct mpx_bounds_dir *bounds_dir)
 116 {
 117         struct mpx_bd_entry *bde = mpx_vaddr_to_bd_entry(vaddr, bounds_dir);
 118         struct mpx_bounds_table *bt = __bd_entry_to_bounds_table(bde);
 119         unsigned long index = __vaddr_bounds_table_index(vaddr);
 120         return &bt->entries[index];
 121 }
 122
 123 #endif /* _MPX_HW_H */