1 #include <linux/ceph/ceph_debug.h> 2 3 #include <linux/bug.h> 4 #include <linux/err.h> 5 #include <linux/random.h> 6 #include <linux/slab.h> 7 #include <linux/types.h> 8 9 #include <linux/ceph/mdsmap.h> 10 #include <linux/ceph/messenger.h> 11 #include <linux/ceph/decode.h> 12 13 #include "super.h" 14 15 16 /* 17 * choose a random mds that is "up" (i.e. has a state > 0), or -1. 18 */ 19 int ceph_mdsmap_get_random_mds(struct ceph_mdsmap *m) 20 { 21 int n = 0; 22 int i; 23 24 /* special case for one mds */ 25 if (1 == m->m_max_mds && m->m_info[0].state > 0) 26 return 0; 27 28 /* count */ 29 for (i = 0; i < m->m_max_mds; i++) 30 if (m->m_info[i].state > 0) 31 n++; 32 if (n == 0) 33 return -1; 34 35 /* pick */ 36 n = prandom_u32() % n; 37 i = 0; 38 for (i = 0; n > 0; i++, n--) 39 while (m->m_info[i].state <= 0) 40 i++; 41 42 return i; 43 } 44 45 #define __decode_and_drop_type(p, end, type, bad) \ 46 do { \ 47 if (*p + sizeof(type) > end) \ 48 goto bad; \ 49 *p += sizeof(type); \ 50 } while (0) 51 52 #define __decode_and_drop_set(p, end, type, bad) \ 53 do { \ 54 u32 n; \ 55 size_t need; \ 56 ceph_decode_32_safe(p, end, n, bad); \ 57 need = sizeof(type) * n; \ 58 ceph_decode_need(p, end, need, bad); \ 59 *p += need; \ 60 } while (0) 61 62 #define __decode_and_drop_map(p, end, ktype, vtype, bad) \ 63 do { \ 64 u32 n; \ 65 size_t need; \ 66 ceph_decode_32_safe(p, end, n, bad); \ 67 need = (sizeof(ktype) + sizeof(vtype)) * n; \ 68 ceph_decode_need(p, end, need, bad); \ 69 *p += need; \ 70 } while (0) 71 72 73 static int __decode_and_drop_compat_set(void **p, void* end) 74 { 75 int i; 76 /* compat, ro_compat, incompat*/ 77 for (i = 0; i < 3; i++) { 78 u32 n; 79 ceph_decode_need(p, end, sizeof(u64) + sizeof(u32), bad); 80 /* mask */ 81 *p += sizeof(u64); 82 /* names (map<u64, string>) */ 83 n = ceph_decode_32(p); 84 while (n-- > 0) { 85 u32 len; 86 ceph_decode_need(p, end, sizeof(u64) + sizeof(u32), 87 bad); 88 *p += sizeof(u64); 89 len = ceph_decode_32(p); 90 ceph_decode_need(p, end, len, bad); 91 *p += len; 92 } 93 } 94 return 0; 95 bad: 96 return -1; 97 } 98 99 /* 100 * Decode an MDS map 101 * 102 * Ignore any fields we don't care about (there are quite a few of 103 * them). 104 */ 105 struct ceph_mdsmap *ceph_mdsmap_decode(void **p, void *end) 106 { 107 struct ceph_mdsmap *m; 108 const void *start = *p; 109 int i, j, n; 110 int err = -EINVAL; 111 u8 mdsmap_v, mdsmap_cv; 112 u16 mdsmap_ev; 113 114 m = kzalloc(sizeof(*m), GFP_NOFS); 115 if (m == NULL) 116 return ERR_PTR(-ENOMEM); 117 118 ceph_decode_need(p, end, 1 + 1, bad); 119 mdsmap_v = ceph_decode_8(p); 120 mdsmap_cv = ceph_decode_8(p); 121 if (mdsmap_v >= 4) { 122 u32 mdsmap_len; 123 ceph_decode_32_safe(p, end, mdsmap_len, bad); 124 if (end < *p + mdsmap_len) 125 goto bad; 126 end = *p + mdsmap_len; 127 } 128 129 ceph_decode_need(p, end, 8*sizeof(u32) + sizeof(u64), bad); 130 m->m_epoch = ceph_decode_32(p); 131 m->m_client_epoch = ceph_decode_32(p); 132 m->m_last_failure = ceph_decode_32(p); 133 m->m_root = ceph_decode_32(p); 134 m->m_session_timeout = ceph_decode_32(p); 135 m->m_session_autoclose = ceph_decode_32(p); 136 m->m_max_file_size = ceph_decode_64(p); 137 m->m_max_mds = ceph_decode_32(p); 138 139 m->m_info = kcalloc(m->m_max_mds, sizeof(*m->m_info), GFP_NOFS); 140 if (m->m_info == NULL) 141 goto nomem; 142 143 /* pick out active nodes from mds_info (state > 0) */ 144 n = ceph_decode_32(p); 145 for (i = 0; i < n; i++) { 146 u64 global_id; 147 u32 namelen; 148 s32 mds, inc, state; 149 u64 state_seq; 150 u8 info_v; 151 void *info_end = NULL; 152 struct ceph_entity_addr addr; 153 u32 num_export_targets; 154 void *pexport_targets = NULL; 155 struct ceph_timespec laggy_since; 156 struct ceph_mds_info *info; 157 158 ceph_decode_need(p, end, sizeof(u64) + 1, bad); 159 global_id = ceph_decode_64(p); 160 info_v= ceph_decode_8(p); 161 if (info_v >= 4) { 162 u32 info_len; 163 u8 info_cv; 164 ceph_decode_need(p, end, 1 + sizeof(u32), bad); 165 info_cv = ceph_decode_8(p); 166 info_len = ceph_decode_32(p); 167 info_end = *p + info_len; 168 if (info_end > end) 169 goto bad; 170 } 171 172 ceph_decode_need(p, end, sizeof(u64) + sizeof(u32), bad); 173 *p += sizeof(u64); 174 namelen = ceph_decode_32(p); /* skip mds name */ 175 *p += namelen; 176 177 ceph_decode_need(p, end, 178 4*sizeof(u32) + sizeof(u64) + 179 sizeof(addr) + sizeof(struct ceph_timespec), 180 bad); 181 mds = ceph_decode_32(p); 182 inc = ceph_decode_32(p); 183 state = ceph_decode_32(p); 184 state_seq = ceph_decode_64(p); 185 ceph_decode_copy(p, &addr, sizeof(addr)); 186 ceph_decode_addr(&addr); 187 ceph_decode_copy(p, &laggy_since, sizeof(laggy_since)); 188 *p += sizeof(u32); 189 ceph_decode_32_safe(p, end, namelen, bad); 190 *p += namelen; 191 if (info_v >= 2) { 192 ceph_decode_32_safe(p, end, num_export_targets, bad); 193 pexport_targets = *p; 194 *p += num_export_targets * sizeof(u32); 195 } else { 196 num_export_targets = 0; 197 } 198 199 if (info_end && *p != info_end) { 200 if (*p > info_end) 201 goto bad; 202 *p = info_end; 203 } 204 205 dout("mdsmap_decode %d/%d %lld mds%d.%d %s %s\n", 206 i+1, n, global_id, mds, inc, 207 ceph_pr_addr(&addr.in_addr), 208 ceph_mds_state_name(state)); 209 210 if (mds < 0 || mds >= m->m_max_mds || state <= 0) 211 continue; 212 213 info = &m->m_info[mds]; 214 info->global_id = global_id; 215 info->state = state; 216 info->addr = addr; 217 info->laggy = (laggy_since.tv_sec != 0 || 218 laggy_since.tv_nsec != 0); 219 info->num_export_targets = num_export_targets; 220 if (num_export_targets) { 221 info->export_targets = kcalloc(num_export_targets, 222 sizeof(u32), GFP_NOFS); 223 if (info->export_targets == NULL) 224 goto nomem; 225 for (j = 0; j < num_export_targets; j++) 226 info->export_targets[j] = 227 ceph_decode_32(&pexport_targets); 228 } else { 229 info->export_targets = NULL; 230 } 231 } 232 233 /* pg_pools */ 234 ceph_decode_32_safe(p, end, n, bad); 235 m->m_num_data_pg_pools = n; 236 m->m_data_pg_pools = kcalloc(n, sizeof(u64), GFP_NOFS); 237 if (!m->m_data_pg_pools) 238 goto nomem; 239 ceph_decode_need(p, end, sizeof(u64)*(n+1), bad); 240 for (i = 0; i < n; i++) 241 m->m_data_pg_pools[i] = ceph_decode_64(p); 242 m->m_cas_pg_pool = ceph_decode_64(p); 243 m->m_enabled = m->m_epoch > 1; 244 245 mdsmap_ev = 1; 246 if (mdsmap_v >= 2) { 247 ceph_decode_16_safe(p, end, mdsmap_ev, bad_ext); 248 } 249 if (mdsmap_ev >= 3) { 250 if (__decode_and_drop_compat_set(p, end) < 0) 251 goto bad_ext; 252 } 253 /* metadata_pool */ 254 if (mdsmap_ev < 5) { 255 __decode_and_drop_type(p, end, u32, bad_ext); 256 } else { 257 __decode_and_drop_type(p, end, u64, bad_ext); 258 } 259 260 /* created + modified + tableserver */ 261 __decode_and_drop_type(p, end, struct ceph_timespec, bad_ext); 262 __decode_and_drop_type(p, end, struct ceph_timespec, bad_ext); 263 __decode_and_drop_type(p, end, u32, bad_ext); 264 265 /* in */ 266 { 267 int num_laggy = 0; 268 ceph_decode_32_safe(p, end, n, bad_ext); 269 ceph_decode_need(p, end, sizeof(u32) * n, bad_ext); 270 271 for (i = 0; i < n; i++) { 272 s32 mds = ceph_decode_32(p); 273 if (mds >= 0 && mds < m->m_max_mds) { 274 if (m->m_info[mds].laggy) 275 num_laggy++; 276 } 277 } 278 m->m_num_laggy = num_laggy; 279 } 280 281 /* inc */ 282 __decode_and_drop_map(p, end, u32, u32, bad_ext); 283 /* up */ 284 __decode_and_drop_map(p, end, u32, u64, bad_ext); 285 /* failed */ 286 __decode_and_drop_set(p, end, u32, bad_ext); 287 /* stopped */ 288 __decode_and_drop_set(p, end, u32, bad_ext); 289 290 if (mdsmap_ev >= 4) { 291 /* last_failure_osd_epoch */ 292 __decode_and_drop_type(p, end, u32, bad_ext); 293 } 294 if (mdsmap_ev >= 6) { 295 /* ever_allowed_snaps */ 296 __decode_and_drop_type(p, end, u8, bad_ext); 297 /* explicitly_allowed_snaps */ 298 __decode_and_drop_type(p, end, u8, bad_ext); 299 } 300 if (mdsmap_ev >= 7) { 301 /* inline_data_enabled */ 302 __decode_and_drop_type(p, end, u8, bad_ext); 303 } 304 if (mdsmap_ev >= 8) { 305 u32 name_len; 306 /* enabled */ 307 ceph_decode_8_safe(p, end, m->m_enabled, bad_ext); 308 ceph_decode_32_safe(p, end, name_len, bad_ext); 309 ceph_decode_need(p, end, name_len, bad_ext); 310 *p += name_len; 311 } 312 /* damaged */ 313 if (mdsmap_ev >= 9) { 314 size_t need; 315 ceph_decode_32_safe(p, end, n, bad_ext); 316 need = sizeof(u32) * n; 317 ceph_decode_need(p, end, need, bad_ext); 318 *p += need; 319 m->m_damaged = n > 0; 320 } else { 321 m->m_damaged = false; 322 } 323 bad_ext: 324 *p = end; 325 dout("mdsmap_decode success epoch %u\n", m->m_epoch); 326 return m; 327 nomem: 328 err = -ENOMEM; 329 goto out_err; 330 bad: 331 pr_err("corrupt mdsmap\n"); 332 print_hex_dump(KERN_DEBUG, "mdsmap: ", 333 DUMP_PREFIX_OFFSET, 16, 1, 334 start, end - start, true); 335 out_err: 336 ceph_mdsmap_destroy(m); 337 return ERR_PTR(err); 338 } 339 340 void ceph_mdsmap_destroy(struct ceph_mdsmap *m) 341 { 342 int i; 343 344 for (i = 0; i < m->m_max_mds; i++) 345 kfree(m->m_info[i].export_targets); 346 kfree(m->m_info); 347 kfree(m->m_data_pg_pools); 348 kfree(m); 349 } 350 351 bool ceph_mdsmap_is_cluster_available(struct ceph_mdsmap *m) 352 { 353 int i, nr_active = 0; 354 if (!m->m_enabled) 355 return false; 356 if (m->m_damaged) 357 return false; 358 if (m->m_num_laggy > 0) 359 return false; 360 for (i = 0; i < m->m_max_mds; i++) { 361 if (m->m_info[i].state == CEPH_MDS_STATE_ACTIVE) 362 nr_active++; 363 } 364 return nr_active > 0; 365 } 366