1 // SPDX-License-Identifier: GPL-2.0 2 #include <linux/ceph/ceph_debug.h> 3 4 #include <linux/bug.h> 5 #include <linux/err.h> 6 #include <linux/random.h> 7 #include <linux/slab.h> 8 #include <linux/types.h> 9 10 #include <linux/ceph/mdsmap.h> 11 #include <linux/ceph/messenger.h> 12 #include <linux/ceph/decode.h> 13 14 #include "super.h" 15 16 17 /* 18 * choose a random mds that is "up" (i.e. has a state > 0), or -1. 19 */ 20 int ceph_mdsmap_get_random_mds(struct ceph_mdsmap *m) 21 { 22 int n = 0; 23 int i; 24 25 /* special case for one mds */ 26 if (1 == m->m_num_mds && m->m_info[0].state > 0) 27 return 0; 28 29 /* count */ 30 for (i = 0; i < m->m_num_mds; i++) 31 if (m->m_info[i].state > 0) 32 n++; 33 if (n == 0) 34 return -1; 35 36 /* pick */ 37 n = prandom_u32() % n; 38 i = 0; 39 for (i = 0; n > 0; i++, n--) 40 while (m->m_info[i].state <= 0) 41 i++; 42 43 return i; 44 } 45 46 #define __decode_and_drop_type(p, end, type, bad) \ 47 do { \ 48 if (*p + sizeof(type) > end) \ 49 goto bad; \ 50 *p += sizeof(type); \ 51 } while (0) 52 53 #define __decode_and_drop_set(p, end, type, bad) \ 54 do { \ 55 u32 n; \ 56 size_t need; \ 57 ceph_decode_32_safe(p, end, n, bad); \ 58 need = sizeof(type) * n; \ 59 ceph_decode_need(p, end, need, bad); \ 60 *p += need; \ 61 } while (0) 62 63 #define __decode_and_drop_map(p, end, ktype, vtype, bad) \ 64 do { \ 65 u32 n; \ 66 size_t need; \ 67 ceph_decode_32_safe(p, end, n, bad); \ 68 need = (sizeof(ktype) + sizeof(vtype)) * n; \ 69 ceph_decode_need(p, end, need, bad); \ 70 *p += need; \ 71 } while (0) 72 73 74 static int __decode_and_drop_compat_set(void **p, void* end) 75 { 76 int i; 77 /* compat, ro_compat, incompat*/ 78 for (i = 0; i < 3; i++) { 79 u32 n; 80 ceph_decode_need(p, end, sizeof(u64) + sizeof(u32), bad); 81 /* mask */ 82 *p += sizeof(u64); 83 /* names (map<u64, string>) */ 84 n = ceph_decode_32(p); 85 while (n-- > 0) { 86 u32 len; 87 ceph_decode_need(p, end, sizeof(u64) + sizeof(u32), 88 bad); 89 *p += sizeof(u64); 90 len = ceph_decode_32(p); 91 ceph_decode_need(p, end, len, bad); 92 *p += len; 93 } 94 } 95 return 0; 96 bad: 97 return -1; 98 } 99 100 /* 101 * Decode an MDS map 102 * 103 * Ignore any fields we don't care about (there are quite a few of 104 * them). 105 */ 106 struct ceph_mdsmap *ceph_mdsmap_decode(void **p, void *end) 107 { 108 struct ceph_mdsmap *m; 109 const void *start = *p; 110 int i, j, n; 111 int err = -EINVAL; 112 u8 mdsmap_v, mdsmap_cv; 113 u16 mdsmap_ev; 114 115 m = kzalloc(sizeof(*m), GFP_NOFS); 116 if (!m) 117 return ERR_PTR(-ENOMEM); 118 119 ceph_decode_need(p, end, 1 + 1, bad); 120 mdsmap_v = ceph_decode_8(p); 121 mdsmap_cv = ceph_decode_8(p); 122 if (mdsmap_v >= 4) { 123 u32 mdsmap_len; 124 ceph_decode_32_safe(p, end, mdsmap_len, bad); 125 if (end < *p + mdsmap_len) 126 goto bad; 127 end = *p + mdsmap_len; 128 } 129 130 ceph_decode_need(p, end, 8*sizeof(u32) + sizeof(u64), bad); 131 m->m_epoch = ceph_decode_32(p); 132 m->m_client_epoch = ceph_decode_32(p); 133 m->m_last_failure = ceph_decode_32(p); 134 m->m_root = ceph_decode_32(p); 135 m->m_session_timeout = ceph_decode_32(p); 136 m->m_session_autoclose = ceph_decode_32(p); 137 m->m_max_file_size = ceph_decode_64(p); 138 m->m_max_mds = ceph_decode_32(p); 139 m->m_num_mds = m->m_max_mds; 140 141 m->m_info = kcalloc(m->m_num_mds, sizeof(*m->m_info), GFP_NOFS); 142 if (!m->m_info) 143 goto nomem; 144 145 /* pick out active nodes from mds_info (state > 0) */ 146 n = ceph_decode_32(p); 147 for (i = 0; i < n; i++) { 148 u64 global_id; 149 u32 namelen; 150 s32 mds, inc, state; 151 u64 state_seq; 152 u8 info_v; 153 void *info_end = NULL; 154 struct ceph_entity_addr addr; 155 u32 num_export_targets; 156 void *pexport_targets = NULL; 157 struct ceph_timespec laggy_since; 158 struct ceph_mds_info *info; 159 160 ceph_decode_need(p, end, sizeof(u64) + 1, bad); 161 global_id = ceph_decode_64(p); 162 info_v= ceph_decode_8(p); 163 if (info_v >= 4) { 164 u32 info_len; 165 u8 info_cv; 166 ceph_decode_need(p, end, 1 + sizeof(u32), bad); 167 info_cv = ceph_decode_8(p); 168 info_len = ceph_decode_32(p); 169 info_end = *p + info_len; 170 if (info_end > end) 171 goto bad; 172 } 173 174 ceph_decode_need(p, end, sizeof(u64) + sizeof(u32), bad); 175 *p += sizeof(u64); 176 namelen = ceph_decode_32(p); /* skip mds name */ 177 *p += namelen; 178 179 ceph_decode_need(p, end, 180 4*sizeof(u32) + sizeof(u64) + 181 sizeof(addr) + sizeof(struct ceph_timespec), 182 bad); 183 mds = ceph_decode_32(p); 184 inc = ceph_decode_32(p); 185 state = ceph_decode_32(p); 186 state_seq = ceph_decode_64(p); 187 ceph_decode_copy(p, &addr, sizeof(addr)); 188 ceph_decode_addr(&addr); 189 ceph_decode_copy(p, &laggy_since, sizeof(laggy_since)); 190 *p += sizeof(u32); 191 ceph_decode_32_safe(p, end, namelen, bad); 192 *p += namelen; 193 if (info_v >= 2) { 194 ceph_decode_32_safe(p, end, num_export_targets, bad); 195 pexport_targets = *p; 196 *p += num_export_targets * sizeof(u32); 197 } else { 198 num_export_targets = 0; 199 } 200 201 if (info_end && *p != info_end) { 202 if (*p > info_end) 203 goto bad; 204 *p = info_end; 205 } 206 207 dout("mdsmap_decode %d/%d %lld mds%d.%d %s %s\n", 208 i+1, n, global_id, mds, inc, 209 ceph_pr_addr(&addr.in_addr), 210 ceph_mds_state_name(state)); 211 212 if (mds < 0 || state <= 0) 213 continue; 214 215 if (mds >= m->m_num_mds) { 216 int new_num = max(mds + 1, m->m_num_mds * 2); 217 void *new_m_info = krealloc(m->m_info, 218 new_num * sizeof(*m->m_info), 219 GFP_NOFS | __GFP_ZERO); 220 if (!new_m_info) 221 goto nomem; 222 m->m_info = new_m_info; 223 m->m_num_mds = new_num; 224 } 225 226 info = &m->m_info[mds]; 227 info->global_id = global_id; 228 info->state = state; 229 info->addr = addr; 230 info->laggy = (laggy_since.tv_sec != 0 || 231 laggy_since.tv_nsec != 0); 232 info->num_export_targets = num_export_targets; 233 if (num_export_targets) { 234 info->export_targets = kcalloc(num_export_targets, 235 sizeof(u32), GFP_NOFS); 236 if (!info->export_targets) 237 goto nomem; 238 for (j = 0; j < num_export_targets; j++) 239 info->export_targets[j] = 240 ceph_decode_32(&pexport_targets); 241 } else { 242 info->export_targets = NULL; 243 } 244 } 245 if (m->m_num_mds > m->m_max_mds) { 246 /* find max up mds */ 247 for (i = m->m_num_mds; i >= m->m_max_mds; i--) { 248 if (i == 0 || m->m_info[i-1].state > 0) 249 break; 250 } 251 m->m_num_mds = i; 252 } 253 254 /* pg_pools */ 255 ceph_decode_32_safe(p, end, n, bad); 256 m->m_num_data_pg_pools = n; 257 m->m_data_pg_pools = kcalloc(n, sizeof(u64), GFP_NOFS); 258 if (!m->m_data_pg_pools) 259 goto nomem; 260 ceph_decode_need(p, end, sizeof(u64)*(n+1), bad); 261 for (i = 0; i < n; i++) 262 m->m_data_pg_pools[i] = ceph_decode_64(p); 263 m->m_cas_pg_pool = ceph_decode_64(p); 264 m->m_enabled = m->m_epoch > 1; 265 266 mdsmap_ev = 1; 267 if (mdsmap_v >= 2) { 268 ceph_decode_16_safe(p, end, mdsmap_ev, bad_ext); 269 } 270 if (mdsmap_ev >= 3) { 271 if (__decode_and_drop_compat_set(p, end) < 0) 272 goto bad_ext; 273 } 274 /* metadata_pool */ 275 if (mdsmap_ev < 5) { 276 __decode_and_drop_type(p, end, u32, bad_ext); 277 } else { 278 __decode_and_drop_type(p, end, u64, bad_ext); 279 } 280 281 /* created + modified + tableserver */ 282 __decode_and_drop_type(p, end, struct ceph_timespec, bad_ext); 283 __decode_and_drop_type(p, end, struct ceph_timespec, bad_ext); 284 __decode_and_drop_type(p, end, u32, bad_ext); 285 286 /* in */ 287 { 288 int num_laggy = 0; 289 ceph_decode_32_safe(p, end, n, bad_ext); 290 ceph_decode_need(p, end, sizeof(u32) * n, bad_ext); 291 292 for (i = 0; i < n; i++) { 293 s32 mds = ceph_decode_32(p); 294 if (mds >= 0 && mds < m->m_num_mds) { 295 if (m->m_info[mds].laggy) 296 num_laggy++; 297 } 298 } 299 m->m_num_laggy = num_laggy; 300 301 if (n > m->m_num_mds) { 302 void *new_m_info = krealloc(m->m_info, 303 n * sizeof(*m->m_info), 304 GFP_NOFS | __GFP_ZERO); 305 if (!new_m_info) 306 goto nomem; 307 m->m_info = new_m_info; 308 } 309 m->m_num_mds = n; 310 } 311 312 /* inc */ 313 __decode_and_drop_map(p, end, u32, u32, bad_ext); 314 /* up */ 315 __decode_and_drop_map(p, end, u32, u64, bad_ext); 316 /* failed */ 317 __decode_and_drop_set(p, end, u32, bad_ext); 318 /* stopped */ 319 __decode_and_drop_set(p, end, u32, bad_ext); 320 321 if (mdsmap_ev >= 4) { 322 /* last_failure_osd_epoch */ 323 __decode_and_drop_type(p, end, u32, bad_ext); 324 } 325 if (mdsmap_ev >= 6) { 326 /* ever_allowed_snaps */ 327 __decode_and_drop_type(p, end, u8, bad_ext); 328 /* explicitly_allowed_snaps */ 329 __decode_and_drop_type(p, end, u8, bad_ext); 330 } 331 if (mdsmap_ev >= 7) { 332 /* inline_data_enabled */ 333 __decode_and_drop_type(p, end, u8, bad_ext); 334 } 335 if (mdsmap_ev >= 8) { 336 u32 name_len; 337 /* enabled */ 338 ceph_decode_8_safe(p, end, m->m_enabled, bad_ext); 339 ceph_decode_32_safe(p, end, name_len, bad_ext); 340 ceph_decode_need(p, end, name_len, bad_ext); 341 *p += name_len; 342 } 343 /* damaged */ 344 if (mdsmap_ev >= 9) { 345 size_t need; 346 ceph_decode_32_safe(p, end, n, bad_ext); 347 need = sizeof(u32) * n; 348 ceph_decode_need(p, end, need, bad_ext); 349 *p += need; 350 m->m_damaged = n > 0; 351 } else { 352 m->m_damaged = false; 353 } 354 bad_ext: 355 *p = end; 356 dout("mdsmap_decode success epoch %u\n", m->m_epoch); 357 return m; 358 nomem: 359 err = -ENOMEM; 360 goto out_err; 361 bad: 362 pr_err("corrupt mdsmap\n"); 363 print_hex_dump(KERN_DEBUG, "mdsmap: ", 364 DUMP_PREFIX_OFFSET, 16, 1, 365 start, end - start, true); 366 out_err: 367 ceph_mdsmap_destroy(m); 368 return ERR_PTR(err); 369 } 370 371 void ceph_mdsmap_destroy(struct ceph_mdsmap *m) 372 { 373 int i; 374 375 for (i = 0; i < m->m_num_mds; i++) 376 kfree(m->m_info[i].export_targets); 377 kfree(m->m_info); 378 kfree(m->m_data_pg_pools); 379 kfree(m); 380 } 381 382 bool ceph_mdsmap_is_cluster_available(struct ceph_mdsmap *m) 383 { 384 int i, nr_active = 0; 385 if (!m->m_enabled) 386 return false; 387 if (m->m_damaged) 388 return false; 389 if (m->m_num_laggy > 0) 390 return false; 391 for (i = 0; i < m->m_num_mds; i++) { 392 if (m->m_info[i].state == CEPH_MDS_STATE_ACTIVE) 393 nr_active++; 394 } 395 return nr_active > 0; 396 } 397