fs/ceph/decode.h

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