LXR linux/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
  51struct mpx_bd_entry {
  52        union {
  53                char x[MPX_BOUNDS_DIR_ENTRY_SIZE_BYTES];
  54                void *contents[1];
  55        };
  56} __attribute__((packed));
  57
  58struct mpx_bt_entry {
  59        union {
  60                char x[MPX_BOUNDS_TABLE_ENTRY_SIZE_BYTES];
  61                unsigned long contents[1];
  62        };
  63} __attribute__((packed));
  64
  65struct mpx_bounds_dir {
  66        struct mpx_bd_entry entries[MPX_BOUNDS_DIR_NR_ENTRIES];
  67} __attribute__((packed));
  68
  69struct mpx_bounds_table {
  70        struct mpx_bt_entry entries[MPX_BOUNDS_TABLE_NR_ENTRIES];
  71} __attribute__((packed));
  72
  73static 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
  80static 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
  86static 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
  92static 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
  99static 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
 105static 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
 114static inline struct mpx_bt_entry *
 115mpx_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 */
 124