include/linux/ceph/decode.h

   1 #ifndef __CEPH_DECODE_H
   2 #define __CEPH_DECODE_H
   3
   4 #include <linux/bug.h>
   5 #include <linux/time.h>
   6 #include <asm/unaligned.h>
   7
   8 #include "types.h"
   9
  10 /*
  11  * in all cases,
  12  *   void **p     pointer to position pointer
  13  *   void *end    pointer to end of buffer (last byte + 1)
  14  */
  15
  16 static inline u64 ceph_decode_64(void **p)
  17 {
  18         u64 v = get_unaligned_le64(*p);
  19         *p += sizeof(u64);
  20         return v;
  21 }
  22 static inline u32 ceph_decode_32(void **p)
  23 {
  24         u32 v = get_unaligned_le32(*p);
  25         *p += sizeof(u32);
  26         return v;
  27 }
  28 static inline u16 ceph_decode_16(void **p)
  29 {
  30         u16 v = get_unaligned_le16(*p);
  31         *p += sizeof(u16);
  32         return v;
  33 }
  34 static inline u8 ceph_decode_8(void **p)
  35 {
  36         u8 v = *(u8 *)*p;
  37         (*p)++;
  38         return v;
  39 }
  40 static inline void ceph_decode_copy(void **p, void *pv, size_t n)
  41 {
  42         memcpy(pv, *p, n);
  43         *p += n;
  44 }
  45
  46 /*
  47  * bounds check input.
  48  */
  49 static inline int ceph_has_room(void **p, void *end, size_t n)
  50 {
  51         return end >= *p && n <= end - *p;
  52 }
  53
  54 #define ceph_decode_need(p, end, n, bad)                \
  55         do {                                            \
  56                 if (!likely(ceph_has_room(p, end, n)))  \
  57                         goto bad;                       \
  58         } while (0)
  59
  60 #define ceph_decode_64_safe(p, end, v, bad)                     \
  61         do {                                                    \
  62                 ceph_decode_need(p, end, sizeof(u64), bad);     \
  63                 v = ceph_decode_64(p);                          \
  64         } while (0)
  65 #define ceph_decode_32_safe(p, end, v, bad)                     \
  66         do {                                                    \
  67                 ceph_decode_need(p, end, sizeof(u32), bad);     \
  68                 v = ceph_decode_32(p);                          \
  69         } while (0)
  70 #define ceph_decode_16_safe(p, end, v, bad)                     \
  71         do {                                                    \
  72                 ceph_decode_need(p, end, sizeof(u16), bad);     \
  73                 v = ceph_decode_16(p);                          \
  74         } while (0)
  75 #define ceph_decode_8_safe(p, end, v, bad)                      \
  76         do {                                                    \
  77                 ceph_decode_need(p, end, sizeof(u8), bad);      \
  78                 v = ceph_decode_8(p);                           \
  79         } while (0)
  80
  81 #define ceph_decode_copy_safe(p, end, pv, n, bad)               \
  82         do {                                                    \
  83                 ceph_decode_need(p, end, n, bad);               \
  84                 ceph_decode_copy(p, pv, n);                     \
  85         } while (0)
  86
  87 /*
  88  * struct ceph_timespec <-> struct timespec
  89  */
  90 static inline void ceph_decode_timespec(struct timespec *ts,
  91                                         const struct ceph_timespec *tv)
  92 {
  93         ts->tv_sec = le32_to_cpu(tv->tv_sec);
  94         ts->tv_nsec = le32_to_cpu(tv->tv_nsec);
  95 }
  96 static inline void ceph_encode_timespec(struct ceph_timespec *tv,
  97                                         const struct timespec *ts)
  98 {
  99         tv->tv_sec = cpu_to_le32(ts->tv_sec);
 100         tv->tv_nsec = cpu_to_le32(ts->tv_nsec);
 101 }
 102
 103 /*
 104  * sockaddr_storage <-> ceph_sockaddr
 105  */
 106 static inline void ceph_encode_addr(struct ceph_entity_addr *a)
 107 {
 108         __be16 ss_family = htons(a->in_addr.ss_family);
 109         a->in_addr.ss_family = *(__u16 *)&ss_family;
 110 }
 111 static inline void ceph_decode_addr(struct ceph_entity_addr *a)
 112 {
 113         __be16 ss_family = *(__be16 *)&a->in_addr.ss_family;
 114         a->in_addr.ss_family = ntohs(ss_family);
 115         WARN_ON(a->in_addr.ss_family == 512);
 116 }
 117
 118 /*
 119  * encoders
 120  */
 121 static inline void ceph_encode_64(void **p, u64 v)
 122 {
 123         put_unaligned_le64(v, (__le64 *)*p);
 124         *p += sizeof(u64);
 125 }
 126 static inline void ceph_encode_32(void **p, u32 v)
 127 {
 128         put_unaligned_le32(v, (__le32 *)*p);
 129         *p += sizeof(u32);
 130 }
 131 static inline void ceph_encode_16(void **p, u16 v)
 132 {
 133         put_unaligned_le16(v, (__le16 *)*p);
 134         *p += sizeof(u16);
 135 }
 136 static inline void ceph_encode_8(void **p, u8 v)
 137 {
 138         *(u8 *)*p = v;
 139         (*p)++;
 140 }
 141 static inline void ceph_encode_copy(void **p, const void *s, int len)
 142 {
 143         memcpy(*p, s, len);
 144         *p += len;
 145 }
 146
 147 /*
 148  * filepath, string encoders
 149  */
 150 static inline void ceph_encode_filepath(void **p, void *end,
 151                                         u64 ino, const char *path)
 152 {
 153         u32 len = path ? strlen(path) : 0;
 154         BUG_ON(*p + sizeof(ino) + sizeof(len) + len > end);
 155         ceph_encode_8(p, 1);
 156         ceph_encode_64(p, ino);
 157         ceph_encode_32(p, len);
 158         if (len)
 159                 memcpy(*p, path, len);
 160         *p += len;
 161 }
 162
 163 static inline void ceph_encode_string(void **p, void *end,
 164                                       const char *s, u32 len)
 165 {
 166         BUG_ON(*p + sizeof(len) + len > end);
 167         ceph_encode_32(p, len);
 168         if (len)
 169                 memcpy(*p, s, len);
 170         *p += len;
 171 }
 172
 173 #define ceph_encode_need(p, end, n, bad)                \
 174         do {                                            \
 175                 if (!likely(ceph_has_room(p, end, n)))  \
 176                         goto bad;                       \
 177         } while (0)
 178
 179 #define ceph_encode_64_safe(p, end, v, bad)                     \
 180         do {                                                    \
 181                 ceph_encode_need(p, end, sizeof(u64), bad);     \
 182                 ceph_encode_64(p, v);                           \
 183         } while (0)
 184 #define ceph_encode_32_safe(p, end, v, bad)                     \
 185         do {                                                    \
 186                 ceph_encode_need(p, end, sizeof(u32), bad);     \
 187                 ceph_encode_32(p, v);                   \
 188         } while (0)
 189 #define ceph_encode_16_safe(p, end, v, bad)                     \
 190         do {                                                    \
 191                 ceph_encode_need(p, end, sizeof(u16), bad);     \
 192                 ceph_encode_16(p, v);                   \
 193         } while (0)
 194
 195 #define ceph_encode_copy_safe(p, end, pv, n, bad)               \
 196         do {                                                    \
 197                 ceph_encode_need(p, end, n, bad);               \
 198                 ceph_encode_copy(p, pv, n);                     \
 199         } while (0)
 200 #define ceph_encode_string_safe(p, end, s, n, bad)              \
 201         do {                                                    \
 202                 ceph_encode_need(p, end, n, bad);               \
 203                 ceph_encode_string(p, end, s, n);               \
 204         } while (0)
 205
 206
 207 #endif