Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1 | /* -*- mode: c; c-basic-offset: 8; -*- |
| 2 | * vim: noexpandtab sw=8 ts=8 sts=0: |
| 3 | * |
| 4 | * dlmmod.c |
| 5 | * |
| 6 | * standalone DLM module |
| 7 | * |
| 8 | * Copyright (C) 2004 Oracle. All rights reserved. |
| 9 | * |
| 10 | * This program is free software; you can redistribute it and/or |
| 11 | * modify it under the terms of the GNU General Public |
| 12 | * License as published by the Free Software Foundation; either |
| 13 | * version 2 of the License, or (at your option) any later version. |
| 14 | * |
| 15 | * This program is distributed in the hope that it will be useful, |
| 16 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 17 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 18 | * General Public License for more details. |
| 19 | * |
| 20 | * You should have received a copy of the GNU General Public |
| 21 | * License along with this program; if not, write to the |
| 22 | * Free Software Foundation, Inc., 59 Temple Place - Suite 330, |
| 23 | * Boston, MA 021110-1307, USA. |
| 24 | * |
| 25 | */ |
| 26 | |
| 27 | |
| 28 | #include <linux/module.h> |
| 29 | #include <linux/fs.h> |
| 30 | #include <linux/types.h> |
| 31 | #include <linux/slab.h> |
| 32 | #include <linux/highmem.h> |
| 33 | #include <linux/utsname.h> |
| 34 | #include <linux/init.h> |
| 35 | #include <linux/sysctl.h> |
| 36 | #include <linux/random.h> |
| 37 | #include <linux/blkdev.h> |
| 38 | #include <linux/socket.h> |
| 39 | #include <linux/inet.h> |
| 40 | #include <linux/spinlock.h> |
| 41 | #include <linux/delay.h> |
| 42 | |
| 43 | |
| 44 | #include "cluster/heartbeat.h" |
| 45 | #include "cluster/nodemanager.h" |
| 46 | #include "cluster/tcp.h" |
| 47 | |
| 48 | #include "dlmapi.h" |
| 49 | #include "dlmcommon.h" |
Adrian Bunk | 82353b5 | 2005-12-19 11:16:07 -0800 | [diff] [blame] | 50 | #include "dlmdomain.h" |
Sunil Mushran | e5a0334 | 2008-03-10 15:16:28 -0700 | [diff] [blame] | 51 | #include "dlmdebug.h" |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 52 | |
| 53 | #define MLOG_MASK_PREFIX (ML_DLM|ML_DLM_MASTER) |
| 54 | #include "cluster/masklog.h" |
| 55 | |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 56 | static void dlm_mle_node_down(struct dlm_ctxt *dlm, |
| 57 | struct dlm_master_list_entry *mle, |
| 58 | struct o2nm_node *node, |
| 59 | int idx); |
| 60 | static void dlm_mle_node_up(struct dlm_ctxt *dlm, |
| 61 | struct dlm_master_list_entry *mle, |
| 62 | struct o2nm_node *node, |
| 63 | int idx); |
| 64 | |
| 65 | static void dlm_assert_master_worker(struct dlm_work_item *item, void *data); |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 66 | static int dlm_do_assert_master(struct dlm_ctxt *dlm, |
| 67 | struct dlm_lock_resource *res, |
| 68 | void *nodemap, u32 flags); |
Sunil Mushran | f3f8546 | 2007-01-29 15:19:16 -0800 | [diff] [blame] | 69 | static void dlm_deref_lockres_worker(struct dlm_work_item *item, void *data); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 70 | |
| 71 | static inline int dlm_mle_equal(struct dlm_ctxt *dlm, |
| 72 | struct dlm_master_list_entry *mle, |
| 73 | const char *name, |
| 74 | unsigned int namelen) |
| 75 | { |
| 76 | struct dlm_lock_resource *res; |
| 77 | |
| 78 | if (dlm != mle->dlm) |
| 79 | return 0; |
| 80 | |
| 81 | if (mle->type == DLM_MLE_BLOCK || |
| 82 | mle->type == DLM_MLE_MIGRATION) { |
| 83 | if (namelen != mle->u.name.len || |
| 84 | memcmp(name, mle->u.name.name, namelen)!=0) |
| 85 | return 0; |
| 86 | } else { |
| 87 | res = mle->u.res; |
| 88 | if (namelen != res->lockname.len || |
| 89 | memcmp(res->lockname.name, name, namelen) != 0) |
| 90 | return 0; |
| 91 | } |
| 92 | return 1; |
| 93 | } |
| 94 | |
Sunil Mushran | 724bdca | 2008-03-10 15:16:20 -0700 | [diff] [blame] | 95 | static struct kmem_cache *dlm_lockres_cache = NULL; |
| 96 | static struct kmem_cache *dlm_lockname_cache = NULL; |
Christoph Lameter | e18b890 | 2006-12-06 20:33:20 -0800 | [diff] [blame] | 97 | static struct kmem_cache *dlm_mle_cache = NULL; |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 98 | |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 99 | static void dlm_mle_release(struct kref *kref); |
| 100 | static void dlm_init_mle(struct dlm_master_list_entry *mle, |
| 101 | enum dlm_mle_type type, |
| 102 | struct dlm_ctxt *dlm, |
| 103 | struct dlm_lock_resource *res, |
| 104 | const char *name, |
| 105 | unsigned int namelen); |
| 106 | static void dlm_put_mle(struct dlm_master_list_entry *mle); |
| 107 | static void __dlm_put_mle(struct dlm_master_list_entry *mle); |
| 108 | static int dlm_find_mle(struct dlm_ctxt *dlm, |
| 109 | struct dlm_master_list_entry **mle, |
| 110 | char *name, unsigned int namelen); |
| 111 | |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 112 | static int dlm_do_master_request(struct dlm_lock_resource *res, |
| 113 | struct dlm_master_list_entry *mle, int to); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 114 | |
| 115 | |
| 116 | static int dlm_wait_for_lock_mastery(struct dlm_ctxt *dlm, |
| 117 | struct dlm_lock_resource *res, |
| 118 | struct dlm_master_list_entry *mle, |
| 119 | int *blocked); |
| 120 | static int dlm_restart_lock_mastery(struct dlm_ctxt *dlm, |
| 121 | struct dlm_lock_resource *res, |
| 122 | struct dlm_master_list_entry *mle, |
| 123 | int blocked); |
| 124 | static int dlm_add_migration_mle(struct dlm_ctxt *dlm, |
| 125 | struct dlm_lock_resource *res, |
| 126 | struct dlm_master_list_entry *mle, |
| 127 | struct dlm_master_list_entry **oldmle, |
| 128 | const char *name, unsigned int namelen, |
| 129 | u8 new_master, u8 master); |
| 130 | |
| 131 | static u8 dlm_pick_migration_target(struct dlm_ctxt *dlm, |
| 132 | struct dlm_lock_resource *res); |
| 133 | static void dlm_remove_nonlocal_locks(struct dlm_ctxt *dlm, |
| 134 | struct dlm_lock_resource *res); |
| 135 | static int dlm_mark_lockres_migrating(struct dlm_ctxt *dlm, |
| 136 | struct dlm_lock_resource *res, |
| 137 | u8 target); |
Kurt Hackel | c03872f | 2006-03-06 14:08:49 -0800 | [diff] [blame] | 138 | static int dlm_pre_master_reco_lockres(struct dlm_ctxt *dlm, |
| 139 | struct dlm_lock_resource *res); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 140 | |
| 141 | |
| 142 | int dlm_is_host_down(int errno) |
| 143 | { |
| 144 | switch (errno) { |
| 145 | case -EBADF: |
| 146 | case -ECONNREFUSED: |
| 147 | case -ENOTCONN: |
| 148 | case -ECONNRESET: |
| 149 | case -EPIPE: |
| 150 | case -EHOSTDOWN: |
| 151 | case -EHOSTUNREACH: |
| 152 | case -ETIMEDOUT: |
| 153 | case -ECONNABORTED: |
| 154 | case -ENETDOWN: |
| 155 | case -ENETUNREACH: |
| 156 | case -ENETRESET: |
| 157 | case -ESHUTDOWN: |
| 158 | case -ENOPROTOOPT: |
| 159 | case -EINVAL: /* if returned from our tcp code, |
| 160 | this means there is no socket */ |
| 161 | return 1; |
| 162 | } |
| 163 | return 0; |
| 164 | } |
| 165 | |
| 166 | |
| 167 | /* |
| 168 | * MASTER LIST FUNCTIONS |
| 169 | */ |
| 170 | |
| 171 | |
| 172 | /* |
| 173 | * regarding master list entries and heartbeat callbacks: |
| 174 | * |
| 175 | * in order to avoid sleeping and allocation that occurs in |
| 176 | * heartbeat, master list entries are simply attached to the |
| 177 | * dlm's established heartbeat callbacks. the mle is attached |
| 178 | * when it is created, and since the dlm->spinlock is held at |
| 179 | * that time, any heartbeat event will be properly discovered |
| 180 | * by the mle. the mle needs to be detached from the |
| 181 | * dlm->mle_hb_events list as soon as heartbeat events are no |
| 182 | * longer useful to the mle, and before the mle is freed. |
| 183 | * |
| 184 | * as a general rule, heartbeat events are no longer needed by |
| 185 | * the mle once an "answer" regarding the lock master has been |
| 186 | * received. |
| 187 | */ |
| 188 | static inline void __dlm_mle_attach_hb_events(struct dlm_ctxt *dlm, |
| 189 | struct dlm_master_list_entry *mle) |
| 190 | { |
| 191 | assert_spin_locked(&dlm->spinlock); |
| 192 | |
| 193 | list_add_tail(&mle->hb_events, &dlm->mle_hb_events); |
| 194 | } |
| 195 | |
| 196 | |
| 197 | static inline void __dlm_mle_detach_hb_events(struct dlm_ctxt *dlm, |
| 198 | struct dlm_master_list_entry *mle) |
| 199 | { |
| 200 | if (!list_empty(&mle->hb_events)) |
| 201 | list_del_init(&mle->hb_events); |
| 202 | } |
| 203 | |
| 204 | |
| 205 | static inline void dlm_mle_detach_hb_events(struct dlm_ctxt *dlm, |
| 206 | struct dlm_master_list_entry *mle) |
| 207 | { |
| 208 | spin_lock(&dlm->spinlock); |
| 209 | __dlm_mle_detach_hb_events(dlm, mle); |
| 210 | spin_unlock(&dlm->spinlock); |
| 211 | } |
| 212 | |
Kurt Hackel | a2bf047 | 2006-04-27 18:51:26 -0700 | [diff] [blame] | 213 | static void dlm_get_mle_inuse(struct dlm_master_list_entry *mle) |
| 214 | { |
| 215 | struct dlm_ctxt *dlm; |
| 216 | dlm = mle->dlm; |
| 217 | |
| 218 | assert_spin_locked(&dlm->spinlock); |
| 219 | assert_spin_locked(&dlm->master_lock); |
| 220 | mle->inuse++; |
| 221 | kref_get(&mle->mle_refs); |
| 222 | } |
| 223 | |
| 224 | static void dlm_put_mle_inuse(struct dlm_master_list_entry *mle) |
| 225 | { |
| 226 | struct dlm_ctxt *dlm; |
| 227 | dlm = mle->dlm; |
| 228 | |
| 229 | spin_lock(&dlm->spinlock); |
| 230 | spin_lock(&dlm->master_lock); |
| 231 | mle->inuse--; |
| 232 | __dlm_put_mle(mle); |
| 233 | spin_unlock(&dlm->master_lock); |
| 234 | spin_unlock(&dlm->spinlock); |
| 235 | |
| 236 | } |
| 237 | |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 238 | /* remove from list and free */ |
| 239 | static void __dlm_put_mle(struct dlm_master_list_entry *mle) |
| 240 | { |
| 241 | struct dlm_ctxt *dlm; |
| 242 | dlm = mle->dlm; |
| 243 | |
| 244 | assert_spin_locked(&dlm->spinlock); |
| 245 | assert_spin_locked(&dlm->master_lock); |
Kurt Hackel | aa85235 | 2006-04-27 19:04:49 -0700 | [diff] [blame] | 246 | if (!atomic_read(&mle->mle_refs.refcount)) { |
| 247 | /* this may or may not crash, but who cares. |
| 248 | * it's a BUG. */ |
| 249 | mlog(ML_ERROR, "bad mle: %p\n", mle); |
| 250 | dlm_print_one_mle(mle); |
| 251 | BUG(); |
| 252 | } else |
| 253 | kref_put(&mle->mle_refs, dlm_mle_release); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 254 | } |
| 255 | |
| 256 | |
| 257 | /* must not have any spinlocks coming in */ |
| 258 | static void dlm_put_mle(struct dlm_master_list_entry *mle) |
| 259 | { |
| 260 | struct dlm_ctxt *dlm; |
| 261 | dlm = mle->dlm; |
| 262 | |
| 263 | spin_lock(&dlm->spinlock); |
| 264 | spin_lock(&dlm->master_lock); |
| 265 | __dlm_put_mle(mle); |
| 266 | spin_unlock(&dlm->master_lock); |
| 267 | spin_unlock(&dlm->spinlock); |
| 268 | } |
| 269 | |
| 270 | static inline void dlm_get_mle(struct dlm_master_list_entry *mle) |
| 271 | { |
| 272 | kref_get(&mle->mle_refs); |
| 273 | } |
| 274 | |
| 275 | static void dlm_init_mle(struct dlm_master_list_entry *mle, |
| 276 | enum dlm_mle_type type, |
| 277 | struct dlm_ctxt *dlm, |
| 278 | struct dlm_lock_resource *res, |
| 279 | const char *name, |
| 280 | unsigned int namelen) |
| 281 | { |
| 282 | assert_spin_locked(&dlm->spinlock); |
| 283 | |
| 284 | mle->dlm = dlm; |
| 285 | mle->type = type; |
| 286 | INIT_LIST_HEAD(&mle->list); |
| 287 | INIT_LIST_HEAD(&mle->hb_events); |
| 288 | memset(mle->maybe_map, 0, sizeof(mle->maybe_map)); |
| 289 | spin_lock_init(&mle->spinlock); |
| 290 | init_waitqueue_head(&mle->wq); |
| 291 | atomic_set(&mle->woken, 0); |
| 292 | kref_init(&mle->mle_refs); |
| 293 | memset(mle->response_map, 0, sizeof(mle->response_map)); |
| 294 | mle->master = O2NM_MAX_NODES; |
| 295 | mle->new_master = O2NM_MAX_NODES; |
Kurt Hackel | a2bf047 | 2006-04-27 18:51:26 -0700 | [diff] [blame] | 296 | mle->inuse = 0; |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 297 | |
| 298 | if (mle->type == DLM_MLE_MASTER) { |
| 299 | BUG_ON(!res); |
| 300 | mle->u.res = res; |
| 301 | } else if (mle->type == DLM_MLE_BLOCK) { |
| 302 | BUG_ON(!name); |
| 303 | memcpy(mle->u.name.name, name, namelen); |
| 304 | mle->u.name.len = namelen; |
| 305 | } else /* DLM_MLE_MIGRATION */ { |
| 306 | BUG_ON(!name); |
| 307 | memcpy(mle->u.name.name, name, namelen); |
| 308 | mle->u.name.len = namelen; |
| 309 | } |
| 310 | |
| 311 | /* copy off the node_map and register hb callbacks on our copy */ |
| 312 | memcpy(mle->node_map, dlm->domain_map, sizeof(mle->node_map)); |
| 313 | memcpy(mle->vote_map, dlm->domain_map, sizeof(mle->vote_map)); |
| 314 | clear_bit(dlm->node_num, mle->vote_map); |
| 315 | clear_bit(dlm->node_num, mle->node_map); |
| 316 | |
| 317 | /* attach the mle to the domain node up/down events */ |
| 318 | __dlm_mle_attach_hb_events(dlm, mle); |
| 319 | } |
| 320 | |
| 321 | |
| 322 | /* returns 1 if found, 0 if not */ |
| 323 | static int dlm_find_mle(struct dlm_ctxt *dlm, |
| 324 | struct dlm_master_list_entry **mle, |
| 325 | char *name, unsigned int namelen) |
| 326 | { |
| 327 | struct dlm_master_list_entry *tmpmle; |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 328 | |
| 329 | assert_spin_locked(&dlm->master_lock); |
| 330 | |
Christoph Hellwig | 800deef | 2007-05-17 16:03:13 +0200 | [diff] [blame] | 331 | list_for_each_entry(tmpmle, &dlm->master_list, list) { |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 332 | if (!dlm_mle_equal(dlm, tmpmle, name, namelen)) |
| 333 | continue; |
| 334 | dlm_get_mle(tmpmle); |
| 335 | *mle = tmpmle; |
| 336 | return 1; |
| 337 | } |
| 338 | return 0; |
| 339 | } |
| 340 | |
| 341 | void dlm_hb_event_notify_attached(struct dlm_ctxt *dlm, int idx, int node_up) |
| 342 | { |
| 343 | struct dlm_master_list_entry *mle; |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 344 | |
| 345 | assert_spin_locked(&dlm->spinlock); |
| 346 | |
Christoph Hellwig | 800deef | 2007-05-17 16:03:13 +0200 | [diff] [blame] | 347 | list_for_each_entry(mle, &dlm->mle_hb_events, hb_events) { |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 348 | if (node_up) |
| 349 | dlm_mle_node_up(dlm, mle, NULL, idx); |
| 350 | else |
| 351 | dlm_mle_node_down(dlm, mle, NULL, idx); |
| 352 | } |
| 353 | } |
| 354 | |
| 355 | static void dlm_mle_node_down(struct dlm_ctxt *dlm, |
| 356 | struct dlm_master_list_entry *mle, |
| 357 | struct o2nm_node *node, int idx) |
| 358 | { |
| 359 | spin_lock(&mle->spinlock); |
| 360 | |
| 361 | if (!test_bit(idx, mle->node_map)) |
| 362 | mlog(0, "node %u already removed from nodemap!\n", idx); |
| 363 | else |
| 364 | clear_bit(idx, mle->node_map); |
| 365 | |
| 366 | spin_unlock(&mle->spinlock); |
| 367 | } |
| 368 | |
| 369 | static void dlm_mle_node_up(struct dlm_ctxt *dlm, |
| 370 | struct dlm_master_list_entry *mle, |
| 371 | struct o2nm_node *node, int idx) |
| 372 | { |
| 373 | spin_lock(&mle->spinlock); |
| 374 | |
| 375 | if (test_bit(idx, mle->node_map)) |
| 376 | mlog(0, "node %u already in node map!\n", idx); |
| 377 | else |
| 378 | set_bit(idx, mle->node_map); |
| 379 | |
| 380 | spin_unlock(&mle->spinlock); |
| 381 | } |
| 382 | |
| 383 | |
| 384 | int dlm_init_mle_cache(void) |
| 385 | { |
Sunil Mushran | 12eb003 | 2008-03-10 15:16:19 -0700 | [diff] [blame] | 386 | dlm_mle_cache = kmem_cache_create("o2dlm_mle", |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 387 | sizeof(struct dlm_master_list_entry), |
| 388 | 0, SLAB_HWCACHE_ALIGN, |
Paul Mundt | 20c2df8 | 2007-07-20 10:11:58 +0900 | [diff] [blame] | 389 | NULL); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 390 | if (dlm_mle_cache == NULL) |
| 391 | return -ENOMEM; |
| 392 | return 0; |
| 393 | } |
| 394 | |
| 395 | void dlm_destroy_mle_cache(void) |
| 396 | { |
| 397 | if (dlm_mle_cache) |
| 398 | kmem_cache_destroy(dlm_mle_cache); |
| 399 | } |
| 400 | |
| 401 | static void dlm_mle_release(struct kref *kref) |
| 402 | { |
| 403 | struct dlm_master_list_entry *mle; |
| 404 | struct dlm_ctxt *dlm; |
| 405 | |
| 406 | mlog_entry_void(); |
| 407 | |
| 408 | mle = container_of(kref, struct dlm_master_list_entry, mle_refs); |
| 409 | dlm = mle->dlm; |
| 410 | |
| 411 | if (mle->type != DLM_MLE_MASTER) { |
| 412 | mlog(0, "calling mle_release for %.*s, type %d\n", |
| 413 | mle->u.name.len, mle->u.name.name, mle->type); |
| 414 | } else { |
| 415 | mlog(0, "calling mle_release for %.*s, type %d\n", |
| 416 | mle->u.res->lockname.len, |
| 417 | mle->u.res->lockname.name, mle->type); |
| 418 | } |
| 419 | assert_spin_locked(&dlm->spinlock); |
| 420 | assert_spin_locked(&dlm->master_lock); |
| 421 | |
| 422 | /* remove from list if not already */ |
| 423 | if (!list_empty(&mle->list)) |
| 424 | list_del_init(&mle->list); |
| 425 | |
| 426 | /* detach the mle from the domain node up/down events */ |
| 427 | __dlm_mle_detach_hb_events(dlm, mle); |
| 428 | |
| 429 | /* NOTE: kfree under spinlock here. |
| 430 | * if this is bad, we can move this to a freelist. */ |
| 431 | kmem_cache_free(dlm_mle_cache, mle); |
| 432 | } |
| 433 | |
| 434 | |
| 435 | /* |
| 436 | * LOCK RESOURCE FUNCTIONS |
| 437 | */ |
| 438 | |
Sunil Mushran | 724bdca | 2008-03-10 15:16:20 -0700 | [diff] [blame] | 439 | int dlm_init_master_caches(void) |
| 440 | { |
| 441 | dlm_lockres_cache = kmem_cache_create("o2dlm_lockres", |
| 442 | sizeof(struct dlm_lock_resource), |
| 443 | 0, SLAB_HWCACHE_ALIGN, NULL); |
| 444 | if (!dlm_lockres_cache) |
| 445 | goto bail; |
| 446 | |
| 447 | dlm_lockname_cache = kmem_cache_create("o2dlm_lockname", |
| 448 | DLM_LOCKID_NAME_MAX, 0, |
| 449 | SLAB_HWCACHE_ALIGN, NULL); |
| 450 | if (!dlm_lockname_cache) |
| 451 | goto bail; |
| 452 | |
| 453 | return 0; |
| 454 | bail: |
| 455 | dlm_destroy_master_caches(); |
| 456 | return -ENOMEM; |
| 457 | } |
| 458 | |
| 459 | void dlm_destroy_master_caches(void) |
| 460 | { |
| 461 | if (dlm_lockname_cache) |
| 462 | kmem_cache_destroy(dlm_lockname_cache); |
| 463 | |
| 464 | if (dlm_lockres_cache) |
| 465 | kmem_cache_destroy(dlm_lockres_cache); |
| 466 | } |
| 467 | |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 468 | static void dlm_set_lockres_owner(struct dlm_ctxt *dlm, |
| 469 | struct dlm_lock_resource *res, |
| 470 | u8 owner) |
| 471 | { |
| 472 | assert_spin_locked(&res->spinlock); |
| 473 | |
| 474 | mlog_entry("%.*s, %u\n", res->lockname.len, res->lockname.name, owner); |
| 475 | |
| 476 | if (owner == dlm->node_num) |
| 477 | atomic_inc(&dlm->local_resources); |
| 478 | else if (owner == DLM_LOCK_RES_OWNER_UNKNOWN) |
| 479 | atomic_inc(&dlm->unknown_resources); |
| 480 | else |
| 481 | atomic_inc(&dlm->remote_resources); |
| 482 | |
| 483 | res->owner = owner; |
| 484 | } |
| 485 | |
| 486 | void dlm_change_lockres_owner(struct dlm_ctxt *dlm, |
| 487 | struct dlm_lock_resource *res, u8 owner) |
| 488 | { |
| 489 | assert_spin_locked(&res->spinlock); |
| 490 | |
| 491 | if (owner == res->owner) |
| 492 | return; |
| 493 | |
| 494 | if (res->owner == dlm->node_num) |
| 495 | atomic_dec(&dlm->local_resources); |
| 496 | else if (res->owner == DLM_LOCK_RES_OWNER_UNKNOWN) |
| 497 | atomic_dec(&dlm->unknown_resources); |
| 498 | else |
| 499 | atomic_dec(&dlm->remote_resources); |
| 500 | |
| 501 | dlm_set_lockres_owner(dlm, res, owner); |
| 502 | } |
| 503 | |
| 504 | |
| 505 | static void dlm_lockres_release(struct kref *kref) |
| 506 | { |
| 507 | struct dlm_lock_resource *res; |
| 508 | |
| 509 | res = container_of(kref, struct dlm_lock_resource, refs); |
| 510 | |
| 511 | /* This should not happen -- all lockres' have a name |
| 512 | * associated with them at init time. */ |
| 513 | BUG_ON(!res->lockname.name); |
| 514 | |
| 515 | mlog(0, "destroying lockres %.*s\n", res->lockname.len, |
| 516 | res->lockname.name); |
| 517 | |
Sunil Mushran | 29576f8 | 2008-03-10 15:16:21 -0700 | [diff] [blame] | 518 | if (!list_empty(&res->tracking)) |
| 519 | list_del_init(&res->tracking); |
| 520 | else { |
| 521 | mlog(ML_ERROR, "Resource %.*s not on the Tracking list\n", |
| 522 | res->lockname.len, res->lockname.name); |
| 523 | dlm_print_one_lock_resource(res); |
| 524 | } |
| 525 | |
Kurt Hackel | a7f90d8 | 2006-04-27 19:24:21 -0700 | [diff] [blame] | 526 | if (!hlist_unhashed(&res->hash_node) || |
| 527 | !list_empty(&res->granted) || |
| 528 | !list_empty(&res->converting) || |
| 529 | !list_empty(&res->blocked) || |
| 530 | !list_empty(&res->dirty) || |
| 531 | !list_empty(&res->recovering) || |
| 532 | !list_empty(&res->purge)) { |
| 533 | mlog(ML_ERROR, |
| 534 | "Going to BUG for resource %.*s." |
| 535 | " We're on a list! [%c%c%c%c%c%c%c]\n", |
| 536 | res->lockname.len, res->lockname.name, |
| 537 | !hlist_unhashed(&res->hash_node) ? 'H' : ' ', |
| 538 | !list_empty(&res->granted) ? 'G' : ' ', |
| 539 | !list_empty(&res->converting) ? 'C' : ' ', |
| 540 | !list_empty(&res->blocked) ? 'B' : ' ', |
| 541 | !list_empty(&res->dirty) ? 'D' : ' ', |
| 542 | !list_empty(&res->recovering) ? 'R' : ' ', |
| 543 | !list_empty(&res->purge) ? 'P' : ' '); |
| 544 | |
| 545 | dlm_print_one_lock_resource(res); |
| 546 | } |
| 547 | |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 548 | /* By the time we're ready to blow this guy away, we shouldn't |
| 549 | * be on any lists. */ |
Mark Fasheh | 81f2094 | 2006-02-28 17:31:22 -0800 | [diff] [blame] | 550 | BUG_ON(!hlist_unhashed(&res->hash_node)); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 551 | BUG_ON(!list_empty(&res->granted)); |
| 552 | BUG_ON(!list_empty(&res->converting)); |
| 553 | BUG_ON(!list_empty(&res->blocked)); |
| 554 | BUG_ON(!list_empty(&res->dirty)); |
| 555 | BUG_ON(!list_empty(&res->recovering)); |
| 556 | BUG_ON(!list_empty(&res->purge)); |
| 557 | |
Sunil Mushran | 724bdca | 2008-03-10 15:16:20 -0700 | [diff] [blame] | 558 | kmem_cache_free(dlm_lockname_cache, (void *)res->lockname.name); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 559 | |
Sunil Mushran | 724bdca | 2008-03-10 15:16:20 -0700 | [diff] [blame] | 560 | kmem_cache_free(dlm_lockres_cache, res); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 561 | } |
| 562 | |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 563 | void dlm_lockres_put(struct dlm_lock_resource *res) |
| 564 | { |
| 565 | kref_put(&res->refs, dlm_lockres_release); |
| 566 | } |
| 567 | |
| 568 | static void dlm_init_lockres(struct dlm_ctxt *dlm, |
| 569 | struct dlm_lock_resource *res, |
| 570 | const char *name, unsigned int namelen) |
| 571 | { |
| 572 | char *qname; |
| 573 | |
| 574 | /* If we memset here, we lose our reference to the kmalloc'd |
| 575 | * res->lockname.name, so be sure to init every field |
| 576 | * correctly! */ |
| 577 | |
| 578 | qname = (char *) res->lockname.name; |
| 579 | memcpy(qname, name, namelen); |
| 580 | |
| 581 | res->lockname.len = namelen; |
Mark Fasheh | a3d3329 | 2006-03-09 17:55:56 -0800 | [diff] [blame] | 582 | res->lockname.hash = dlm_lockid_hash(name, namelen); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 583 | |
| 584 | init_waitqueue_head(&res->wq); |
| 585 | spin_lock_init(&res->spinlock); |
Mark Fasheh | 81f2094 | 2006-02-28 17:31:22 -0800 | [diff] [blame] | 586 | INIT_HLIST_NODE(&res->hash_node); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 587 | INIT_LIST_HEAD(&res->granted); |
| 588 | INIT_LIST_HEAD(&res->converting); |
| 589 | INIT_LIST_HEAD(&res->blocked); |
| 590 | INIT_LIST_HEAD(&res->dirty); |
| 591 | INIT_LIST_HEAD(&res->recovering); |
| 592 | INIT_LIST_HEAD(&res->purge); |
Sunil Mushran | 29576f8 | 2008-03-10 15:16:21 -0700 | [diff] [blame] | 593 | INIT_LIST_HEAD(&res->tracking); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 594 | atomic_set(&res->asts_reserved, 0); |
| 595 | res->migration_pending = 0; |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 596 | res->inflight_locks = 0; |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 597 | |
| 598 | kref_init(&res->refs); |
| 599 | |
| 600 | /* just for consistency */ |
| 601 | spin_lock(&res->spinlock); |
| 602 | dlm_set_lockres_owner(dlm, res, DLM_LOCK_RES_OWNER_UNKNOWN); |
| 603 | spin_unlock(&res->spinlock); |
| 604 | |
| 605 | res->state = DLM_LOCK_RES_IN_PROGRESS; |
| 606 | |
| 607 | res->last_used = 0; |
| 608 | |
Sunil Mushran | 18c6ac3 | 2008-07-07 10:06:29 -0700 | [diff] [blame^] | 609 | spin_lock(&dlm->spinlock); |
Sunil Mushran | 29576f8 | 2008-03-10 15:16:21 -0700 | [diff] [blame] | 610 | list_add_tail(&res->tracking, &dlm->tracking_list); |
Sunil Mushran | 18c6ac3 | 2008-07-07 10:06:29 -0700 | [diff] [blame^] | 611 | spin_unlock(&dlm->spinlock); |
Sunil Mushran | 29576f8 | 2008-03-10 15:16:21 -0700 | [diff] [blame] | 612 | |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 613 | memset(res->lvb, 0, DLM_LVB_LEN); |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 614 | memset(res->refmap, 0, sizeof(res->refmap)); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 615 | } |
| 616 | |
| 617 | struct dlm_lock_resource *dlm_new_lockres(struct dlm_ctxt *dlm, |
| 618 | const char *name, |
| 619 | unsigned int namelen) |
| 620 | { |
Sunil Mushran | 724bdca | 2008-03-10 15:16:20 -0700 | [diff] [blame] | 621 | struct dlm_lock_resource *res = NULL; |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 622 | |
Sunil Mushran | 724bdca | 2008-03-10 15:16:20 -0700 | [diff] [blame] | 623 | res = (struct dlm_lock_resource *) |
| 624 | kmem_cache_zalloc(dlm_lockres_cache, GFP_NOFS); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 625 | if (!res) |
Sunil Mushran | 724bdca | 2008-03-10 15:16:20 -0700 | [diff] [blame] | 626 | goto error; |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 627 | |
Sunil Mushran | 724bdca | 2008-03-10 15:16:20 -0700 | [diff] [blame] | 628 | res->lockname.name = (char *) |
| 629 | kmem_cache_zalloc(dlm_lockname_cache, GFP_NOFS); |
| 630 | if (!res->lockname.name) |
| 631 | goto error; |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 632 | |
| 633 | dlm_init_lockres(dlm, res, name, namelen); |
| 634 | return res; |
Sunil Mushran | 724bdca | 2008-03-10 15:16:20 -0700 | [diff] [blame] | 635 | |
| 636 | error: |
| 637 | if (res && res->lockname.name) |
| 638 | kmem_cache_free(dlm_lockname_cache, (void *)res->lockname.name); |
| 639 | |
| 640 | if (res) |
| 641 | kmem_cache_free(dlm_lockres_cache, res); |
| 642 | return NULL; |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 643 | } |
| 644 | |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 645 | void __dlm_lockres_grab_inflight_ref(struct dlm_ctxt *dlm, |
| 646 | struct dlm_lock_resource *res, |
| 647 | int new_lockres, |
| 648 | const char *file, |
| 649 | int line) |
| 650 | { |
| 651 | if (!new_lockres) |
| 652 | assert_spin_locked(&res->spinlock); |
| 653 | |
| 654 | if (!test_bit(dlm->node_num, res->refmap)) { |
| 655 | BUG_ON(res->inflight_locks != 0); |
| 656 | dlm_lockres_set_refmap_bit(dlm->node_num, res); |
| 657 | } |
| 658 | res->inflight_locks++; |
| 659 | mlog(0, "%s:%.*s: inflight++: now %u\n", |
| 660 | dlm->name, res->lockname.len, res->lockname.name, |
| 661 | res->inflight_locks); |
| 662 | } |
| 663 | |
| 664 | void __dlm_lockres_drop_inflight_ref(struct dlm_ctxt *dlm, |
| 665 | struct dlm_lock_resource *res, |
| 666 | const char *file, |
| 667 | int line) |
| 668 | { |
| 669 | assert_spin_locked(&res->spinlock); |
| 670 | |
| 671 | BUG_ON(res->inflight_locks == 0); |
| 672 | res->inflight_locks--; |
| 673 | mlog(0, "%s:%.*s: inflight--: now %u\n", |
| 674 | dlm->name, res->lockname.len, res->lockname.name, |
| 675 | res->inflight_locks); |
| 676 | if (res->inflight_locks == 0) |
| 677 | dlm_lockres_clear_refmap_bit(dlm->node_num, res); |
| 678 | wake_up(&res->wq); |
| 679 | } |
| 680 | |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 681 | /* |
| 682 | * lookup a lock resource by name. |
| 683 | * may already exist in the hashtable. |
| 684 | * lockid is null terminated |
| 685 | * |
| 686 | * if not, allocate enough for the lockres and for |
| 687 | * the temporary structure used in doing the mastering. |
| 688 | * |
| 689 | * also, do a lookup in the dlm->master_list to see |
| 690 | * if another node has begun mastering the same lock. |
| 691 | * if so, there should be a block entry in there |
| 692 | * for this name, and we should *not* attempt to master |
| 693 | * the lock here. need to wait around for that node |
| 694 | * to assert_master (or die). |
| 695 | * |
| 696 | */ |
| 697 | struct dlm_lock_resource * dlm_get_lock_resource(struct dlm_ctxt *dlm, |
| 698 | const char *lockid, |
Mark Fasheh | 3384f3d | 2006-09-08 11:38:29 -0700 | [diff] [blame] | 699 | int namelen, |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 700 | int flags) |
| 701 | { |
| 702 | struct dlm_lock_resource *tmpres=NULL, *res=NULL; |
| 703 | struct dlm_master_list_entry *mle = NULL; |
| 704 | struct dlm_master_list_entry *alloc_mle = NULL; |
| 705 | int blocked = 0; |
| 706 | int ret, nodenum; |
| 707 | struct dlm_node_iter iter; |
Mark Fasheh | 3384f3d | 2006-09-08 11:38:29 -0700 | [diff] [blame] | 708 | unsigned int hash; |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 709 | int tries = 0; |
Kurt Hackel | c03872f | 2006-03-06 14:08:49 -0800 | [diff] [blame] | 710 | int bit, wait_on_recovery = 0; |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 711 | int drop_inflight_if_nonlocal = 0; |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 712 | |
| 713 | BUG_ON(!lockid); |
| 714 | |
Mark Fasheh | a3d3329 | 2006-03-09 17:55:56 -0800 | [diff] [blame] | 715 | hash = dlm_lockid_hash(lockid, namelen); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 716 | |
| 717 | mlog(0, "get lockres %s (len %d)\n", lockid, namelen); |
| 718 | |
| 719 | lookup: |
| 720 | spin_lock(&dlm->spinlock); |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 721 | tmpres = __dlm_lookup_lockres_full(dlm, lockid, namelen, hash); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 722 | if (tmpres) { |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 723 | int dropping_ref = 0; |
| 724 | |
| 725 | spin_lock(&tmpres->spinlock); |
| 726 | if (tmpres->owner == dlm->node_num) { |
| 727 | BUG_ON(tmpres->state & DLM_LOCK_RES_DROPPING_REF); |
| 728 | dlm_lockres_grab_inflight_ref(dlm, tmpres); |
| 729 | } else if (tmpres->state & DLM_LOCK_RES_DROPPING_REF) |
| 730 | dropping_ref = 1; |
| 731 | spin_unlock(&tmpres->spinlock); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 732 | spin_unlock(&dlm->spinlock); |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 733 | |
| 734 | /* wait until done messaging the master, drop our ref to allow |
| 735 | * the lockres to be purged, start over. */ |
| 736 | if (dropping_ref) { |
| 737 | spin_lock(&tmpres->spinlock); |
| 738 | __dlm_wait_on_lockres_flags(tmpres, DLM_LOCK_RES_DROPPING_REF); |
| 739 | spin_unlock(&tmpres->spinlock); |
| 740 | dlm_lockres_put(tmpres); |
| 741 | tmpres = NULL; |
| 742 | goto lookup; |
| 743 | } |
| 744 | |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 745 | mlog(0, "found in hash!\n"); |
| 746 | if (res) |
| 747 | dlm_lockres_put(res); |
| 748 | res = tmpres; |
| 749 | goto leave; |
| 750 | } |
| 751 | |
| 752 | if (!res) { |
| 753 | spin_unlock(&dlm->spinlock); |
| 754 | mlog(0, "allocating a new resource\n"); |
| 755 | /* nothing found and we need to allocate one. */ |
| 756 | alloc_mle = (struct dlm_master_list_entry *) |
Kurt Hackel | ad8100e | 2006-05-01 14:25:21 -0700 | [diff] [blame] | 757 | kmem_cache_alloc(dlm_mle_cache, GFP_NOFS); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 758 | if (!alloc_mle) |
| 759 | goto leave; |
| 760 | res = dlm_new_lockres(dlm, lockid, namelen); |
| 761 | if (!res) |
| 762 | goto leave; |
| 763 | goto lookup; |
| 764 | } |
| 765 | |
| 766 | mlog(0, "no lockres found, allocated our own: %p\n", res); |
| 767 | |
| 768 | if (flags & LKM_LOCAL) { |
| 769 | /* caller knows it's safe to assume it's not mastered elsewhere |
| 770 | * DONE! return right away */ |
| 771 | spin_lock(&res->spinlock); |
| 772 | dlm_change_lockres_owner(dlm, res, dlm->node_num); |
| 773 | __dlm_insert_lockres(dlm, res); |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 774 | dlm_lockres_grab_inflight_ref(dlm, res); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 775 | spin_unlock(&res->spinlock); |
| 776 | spin_unlock(&dlm->spinlock); |
| 777 | /* lockres still marked IN_PROGRESS */ |
| 778 | goto wake_waiters; |
| 779 | } |
| 780 | |
| 781 | /* check master list to see if another node has started mastering it */ |
| 782 | spin_lock(&dlm->master_lock); |
| 783 | |
| 784 | /* if we found a block, wait for lock to be mastered by another node */ |
| 785 | blocked = dlm_find_mle(dlm, &mle, (char *)lockid, namelen); |
| 786 | if (blocked) { |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 787 | int mig; |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 788 | if (mle->type == DLM_MLE_MASTER) { |
| 789 | mlog(ML_ERROR, "master entry for nonexistent lock!\n"); |
| 790 | BUG(); |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 791 | } |
| 792 | mig = (mle->type == DLM_MLE_MIGRATION); |
| 793 | /* if there is a migration in progress, let the migration |
| 794 | * finish before continuing. we can wait for the absence |
| 795 | * of the MIGRATION mle: either the migrate finished or |
| 796 | * one of the nodes died and the mle was cleaned up. |
| 797 | * if there is a BLOCK here, but it already has a master |
| 798 | * set, we are too late. the master does not have a ref |
| 799 | * for us in the refmap. detach the mle and drop it. |
| 800 | * either way, go back to the top and start over. */ |
| 801 | if (mig || mle->master != O2NM_MAX_NODES) { |
| 802 | BUG_ON(mig && mle->master == dlm->node_num); |
| 803 | /* we arrived too late. the master does not |
| 804 | * have a ref for us. retry. */ |
| 805 | mlog(0, "%s:%.*s: late on %s\n", |
| 806 | dlm->name, namelen, lockid, |
| 807 | mig ? "MIGRATION" : "BLOCK"); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 808 | spin_unlock(&dlm->master_lock); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 809 | spin_unlock(&dlm->spinlock); |
| 810 | |
| 811 | /* master is known, detach */ |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 812 | if (!mig) |
| 813 | dlm_mle_detach_hb_events(dlm, mle); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 814 | dlm_put_mle(mle); |
| 815 | mle = NULL; |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 816 | /* this is lame, but we cant wait on either |
| 817 | * the mle or lockres waitqueue here */ |
| 818 | if (mig) |
| 819 | msleep(100); |
| 820 | goto lookup; |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 821 | } |
| 822 | } else { |
| 823 | /* go ahead and try to master lock on this node */ |
| 824 | mle = alloc_mle; |
| 825 | /* make sure this does not get freed below */ |
| 826 | alloc_mle = NULL; |
| 827 | dlm_init_mle(mle, DLM_MLE_MASTER, dlm, res, NULL, 0); |
| 828 | set_bit(dlm->node_num, mle->maybe_map); |
| 829 | list_add(&mle->list, &dlm->master_list); |
Kurt Hackel | c03872f | 2006-03-06 14:08:49 -0800 | [diff] [blame] | 830 | |
| 831 | /* still holding the dlm spinlock, check the recovery map |
| 832 | * to see if there are any nodes that still need to be |
| 833 | * considered. these will not appear in the mle nodemap |
| 834 | * but they might own this lockres. wait on them. */ |
| 835 | bit = find_next_bit(dlm->recovery_map, O2NM_MAX_NODES, 0); |
| 836 | if (bit < O2NM_MAX_NODES) { |
Joe Perches | 2759236 | 2007-11-19 17:53:34 -0800 | [diff] [blame] | 837 | mlog(ML_NOTICE, "%s:%.*s: at least one node (%d) to " |
Kurt Hackel | c03872f | 2006-03-06 14:08:49 -0800 | [diff] [blame] | 838 | "recover before lock mastery can begin\n", |
| 839 | dlm->name, namelen, (char *)lockid, bit); |
| 840 | wait_on_recovery = 1; |
| 841 | } |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 842 | } |
| 843 | |
| 844 | /* at this point there is either a DLM_MLE_BLOCK or a |
| 845 | * DLM_MLE_MASTER on the master list, so it's safe to add the |
| 846 | * lockres to the hashtable. anyone who finds the lock will |
| 847 | * still have to wait on the IN_PROGRESS. */ |
| 848 | |
| 849 | /* finally add the lockres to its hash bucket */ |
| 850 | __dlm_insert_lockres(dlm, res); |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 851 | /* since this lockres is new it doesnt not require the spinlock */ |
| 852 | dlm_lockres_grab_inflight_ref_new(dlm, res); |
| 853 | |
| 854 | /* if this node does not become the master make sure to drop |
| 855 | * this inflight reference below */ |
| 856 | drop_inflight_if_nonlocal = 1; |
| 857 | |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 858 | /* get an extra ref on the mle in case this is a BLOCK |
| 859 | * if so, the creator of the BLOCK may try to put the last |
| 860 | * ref at this time in the assert master handler, so we |
| 861 | * need an extra one to keep from a bad ptr deref. */ |
Kurt Hackel | a2bf047 | 2006-04-27 18:51:26 -0700 | [diff] [blame] | 862 | dlm_get_mle_inuse(mle); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 863 | spin_unlock(&dlm->master_lock); |
| 864 | spin_unlock(&dlm->spinlock); |
| 865 | |
Kurt Hackel | e7e69eb | 2006-05-01 11:49:52 -0700 | [diff] [blame] | 866 | redo_request: |
Kurt Hackel | c03872f | 2006-03-06 14:08:49 -0800 | [diff] [blame] | 867 | while (wait_on_recovery) { |
| 868 | /* any cluster changes that occurred after dropping the |
| 869 | * dlm spinlock would be detectable be a change on the mle, |
| 870 | * so we only need to clear out the recovery map once. */ |
| 871 | if (dlm_is_recovery_lock(lockid, namelen)) { |
| 872 | mlog(ML_NOTICE, "%s: recovery map is not empty, but " |
| 873 | "must master $RECOVERY lock now\n", dlm->name); |
| 874 | if (!dlm_pre_master_reco_lockres(dlm, res)) |
| 875 | wait_on_recovery = 0; |
| 876 | else { |
| 877 | mlog(0, "%s: waiting 500ms for heartbeat state " |
| 878 | "change\n", dlm->name); |
| 879 | msleep(500); |
| 880 | } |
| 881 | continue; |
| 882 | } |
| 883 | |
| 884 | dlm_kick_recovery_thread(dlm); |
Kurt Hackel | aa087b8 | 2006-05-01 12:02:07 -0700 | [diff] [blame] | 885 | msleep(1000); |
Kurt Hackel | c03872f | 2006-03-06 14:08:49 -0800 | [diff] [blame] | 886 | dlm_wait_for_recovery(dlm); |
| 887 | |
| 888 | spin_lock(&dlm->spinlock); |
| 889 | bit = find_next_bit(dlm->recovery_map, O2NM_MAX_NODES, 0); |
| 890 | if (bit < O2NM_MAX_NODES) { |
Joe Perches | 2759236 | 2007-11-19 17:53:34 -0800 | [diff] [blame] | 891 | mlog(ML_NOTICE, "%s:%.*s: at least one node (%d) to " |
Kurt Hackel | c03872f | 2006-03-06 14:08:49 -0800 | [diff] [blame] | 892 | "recover before lock mastery can begin\n", |
| 893 | dlm->name, namelen, (char *)lockid, bit); |
| 894 | wait_on_recovery = 1; |
| 895 | } else |
| 896 | wait_on_recovery = 0; |
| 897 | spin_unlock(&dlm->spinlock); |
Kurt Hackel | b7084ab | 2006-05-01 13:54:07 -0700 | [diff] [blame] | 898 | |
| 899 | if (wait_on_recovery) |
| 900 | dlm_wait_for_node_recovery(dlm, bit, 10000); |
Kurt Hackel | c03872f | 2006-03-06 14:08:49 -0800 | [diff] [blame] | 901 | } |
| 902 | |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 903 | /* must wait for lock to be mastered elsewhere */ |
| 904 | if (blocked) |
| 905 | goto wait; |
| 906 | |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 907 | ret = -EINVAL; |
| 908 | dlm_node_iter_init(mle->vote_map, &iter); |
| 909 | while ((nodenum = dlm_node_iter_next(&iter)) >= 0) { |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 910 | ret = dlm_do_master_request(res, mle, nodenum); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 911 | if (ret < 0) |
| 912 | mlog_errno(ret); |
| 913 | if (mle->master != O2NM_MAX_NODES) { |
| 914 | /* found a master ! */ |
Kurt Hackel | 9c6510a | 2006-03-02 18:09:26 -0800 | [diff] [blame] | 915 | if (mle->master <= nodenum) |
| 916 | break; |
| 917 | /* if our master request has not reached the master |
| 918 | * yet, keep going until it does. this is how the |
| 919 | * master will know that asserts are needed back to |
| 920 | * the lower nodes. */ |
| 921 | mlog(0, "%s:%.*s: requests only up to %u but master " |
| 922 | "is %u, keep going\n", dlm->name, namelen, |
| 923 | lockid, nodenum, mle->master); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 924 | } |
| 925 | } |
| 926 | |
| 927 | wait: |
| 928 | /* keep going until the response map includes all nodes */ |
| 929 | ret = dlm_wait_for_lock_mastery(dlm, res, mle, &blocked); |
| 930 | if (ret < 0) { |
Kurt Hackel | e7e69eb | 2006-05-01 11:49:52 -0700 | [diff] [blame] | 931 | wait_on_recovery = 1; |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 932 | mlog(0, "%s:%.*s: node map changed, redo the " |
| 933 | "master request now, blocked=%d\n", |
| 934 | dlm->name, res->lockname.len, |
| 935 | res->lockname.name, blocked); |
| 936 | if (++tries > 20) { |
| 937 | mlog(ML_ERROR, "%s:%.*s: spinning on " |
| 938 | "dlm_wait_for_lock_mastery, blocked=%d\n", |
| 939 | dlm->name, res->lockname.len, |
| 940 | res->lockname.name, blocked); |
| 941 | dlm_print_one_lock_resource(res); |
Mark Fasheh | 8a9343f | 2006-05-01 14:55:10 -0700 | [diff] [blame] | 942 | dlm_print_one_mle(mle); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 943 | tries = 0; |
| 944 | } |
| 945 | goto redo_request; |
| 946 | } |
| 947 | |
| 948 | mlog(0, "lockres mastered by %u\n", res->owner); |
| 949 | /* make sure we never continue without this */ |
| 950 | BUG_ON(res->owner == O2NM_MAX_NODES); |
| 951 | |
| 952 | /* master is known, detach if not already detached */ |
| 953 | dlm_mle_detach_hb_events(dlm, mle); |
| 954 | dlm_put_mle(mle); |
| 955 | /* put the extra ref */ |
Kurt Hackel | a2bf047 | 2006-04-27 18:51:26 -0700 | [diff] [blame] | 956 | dlm_put_mle_inuse(mle); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 957 | |
| 958 | wake_waiters: |
| 959 | spin_lock(&res->spinlock); |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 960 | if (res->owner != dlm->node_num && drop_inflight_if_nonlocal) |
| 961 | dlm_lockres_drop_inflight_ref(dlm, res); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 962 | res->state &= ~DLM_LOCK_RES_IN_PROGRESS; |
| 963 | spin_unlock(&res->spinlock); |
| 964 | wake_up(&res->wq); |
| 965 | |
| 966 | leave: |
| 967 | /* need to free the unused mle */ |
| 968 | if (alloc_mle) |
| 969 | kmem_cache_free(dlm_mle_cache, alloc_mle); |
| 970 | |
| 971 | return res; |
| 972 | } |
| 973 | |
| 974 | |
| 975 | #define DLM_MASTERY_TIMEOUT_MS 5000 |
| 976 | |
| 977 | static int dlm_wait_for_lock_mastery(struct dlm_ctxt *dlm, |
| 978 | struct dlm_lock_resource *res, |
| 979 | struct dlm_master_list_entry *mle, |
| 980 | int *blocked) |
| 981 | { |
| 982 | u8 m; |
| 983 | int ret, bit; |
| 984 | int map_changed, voting_done; |
| 985 | int assert, sleep; |
| 986 | |
| 987 | recheck: |
| 988 | ret = 0; |
| 989 | assert = 0; |
| 990 | |
| 991 | /* check if another node has already become the owner */ |
| 992 | spin_lock(&res->spinlock); |
| 993 | if (res->owner != DLM_LOCK_RES_OWNER_UNKNOWN) { |
Kurt Hackel | 9c6510a | 2006-03-02 18:09:26 -0800 | [diff] [blame] | 994 | mlog(0, "%s:%.*s: owner is suddenly %u\n", dlm->name, |
| 995 | res->lockname.len, res->lockname.name, res->owner); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 996 | spin_unlock(&res->spinlock); |
Kurt Hackel | 9c6510a | 2006-03-02 18:09:26 -0800 | [diff] [blame] | 997 | /* this will cause the master to re-assert across |
| 998 | * the whole cluster, freeing up mles */ |
Kurt Hackel | 588e009 | 2006-05-01 11:22:06 -0700 | [diff] [blame] | 999 | if (res->owner != dlm->node_num) { |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 1000 | ret = dlm_do_master_request(res, mle, res->owner); |
Kurt Hackel | 588e009 | 2006-05-01 11:22:06 -0700 | [diff] [blame] | 1001 | if (ret < 0) { |
| 1002 | /* give recovery a chance to run */ |
| 1003 | mlog(ML_ERROR, "link to %u went down?: %d\n", res->owner, ret); |
| 1004 | msleep(500); |
| 1005 | goto recheck; |
| 1006 | } |
Kurt Hackel | 9c6510a | 2006-03-02 18:09:26 -0800 | [diff] [blame] | 1007 | } |
| 1008 | ret = 0; |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1009 | goto leave; |
| 1010 | } |
| 1011 | spin_unlock(&res->spinlock); |
| 1012 | |
| 1013 | spin_lock(&mle->spinlock); |
| 1014 | m = mle->master; |
| 1015 | map_changed = (memcmp(mle->vote_map, mle->node_map, |
| 1016 | sizeof(mle->vote_map)) != 0); |
| 1017 | voting_done = (memcmp(mle->vote_map, mle->response_map, |
| 1018 | sizeof(mle->vote_map)) == 0); |
| 1019 | |
| 1020 | /* restart if we hit any errors */ |
| 1021 | if (map_changed) { |
| 1022 | int b; |
| 1023 | mlog(0, "%s: %.*s: node map changed, restarting\n", |
| 1024 | dlm->name, res->lockname.len, res->lockname.name); |
| 1025 | ret = dlm_restart_lock_mastery(dlm, res, mle, *blocked); |
| 1026 | b = (mle->type == DLM_MLE_BLOCK); |
| 1027 | if ((*blocked && !b) || (!*blocked && b)) { |
| 1028 | mlog(0, "%s:%.*s: status change: old=%d new=%d\n", |
| 1029 | dlm->name, res->lockname.len, res->lockname.name, |
| 1030 | *blocked, b); |
| 1031 | *blocked = b; |
| 1032 | } |
| 1033 | spin_unlock(&mle->spinlock); |
| 1034 | if (ret < 0) { |
| 1035 | mlog_errno(ret); |
| 1036 | goto leave; |
| 1037 | } |
| 1038 | mlog(0, "%s:%.*s: restart lock mastery succeeded, " |
| 1039 | "rechecking now\n", dlm->name, res->lockname.len, |
| 1040 | res->lockname.name); |
| 1041 | goto recheck; |
Kurt Hackel | aa85235 | 2006-04-27 19:04:49 -0700 | [diff] [blame] | 1042 | } else { |
| 1043 | if (!voting_done) { |
| 1044 | mlog(0, "map not changed and voting not done " |
| 1045 | "for %s:%.*s\n", dlm->name, res->lockname.len, |
| 1046 | res->lockname.name); |
| 1047 | } |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1048 | } |
| 1049 | |
| 1050 | if (m != O2NM_MAX_NODES) { |
| 1051 | /* another node has done an assert! |
| 1052 | * all done! */ |
| 1053 | sleep = 0; |
| 1054 | } else { |
| 1055 | sleep = 1; |
| 1056 | /* have all nodes responded? */ |
| 1057 | if (voting_done && !*blocked) { |
| 1058 | bit = find_next_bit(mle->maybe_map, O2NM_MAX_NODES, 0); |
| 1059 | if (dlm->node_num <= bit) { |
| 1060 | /* my node number is lowest. |
| 1061 | * now tell other nodes that I am |
| 1062 | * mastering this. */ |
| 1063 | mle->master = dlm->node_num; |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 1064 | /* ref was grabbed in get_lock_resource |
| 1065 | * will be dropped in dlmlock_master */ |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1066 | assert = 1; |
| 1067 | sleep = 0; |
| 1068 | } |
| 1069 | /* if voting is done, but we have not received |
| 1070 | * an assert master yet, we must sleep */ |
| 1071 | } |
| 1072 | } |
| 1073 | |
| 1074 | spin_unlock(&mle->spinlock); |
| 1075 | |
| 1076 | /* sleep if we haven't finished voting yet */ |
| 1077 | if (sleep) { |
| 1078 | unsigned long timeo = msecs_to_jiffies(DLM_MASTERY_TIMEOUT_MS); |
| 1079 | |
| 1080 | /* |
| 1081 | if (atomic_read(&mle->mle_refs.refcount) < 2) |
| 1082 | mlog(ML_ERROR, "mle (%p) refs=%d, name=%.*s\n", mle, |
| 1083 | atomic_read(&mle->mle_refs.refcount), |
| 1084 | res->lockname.len, res->lockname.name); |
| 1085 | */ |
| 1086 | atomic_set(&mle->woken, 0); |
| 1087 | (void)wait_event_timeout(mle->wq, |
| 1088 | (atomic_read(&mle->woken) == 1), |
| 1089 | timeo); |
| 1090 | if (res->owner == O2NM_MAX_NODES) { |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 1091 | mlog(0, "%s:%.*s: waiting again\n", dlm->name, |
| 1092 | res->lockname.len, res->lockname.name); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1093 | goto recheck; |
| 1094 | } |
| 1095 | mlog(0, "done waiting, master is %u\n", res->owner); |
| 1096 | ret = 0; |
| 1097 | goto leave; |
| 1098 | } |
| 1099 | |
| 1100 | ret = 0; /* done */ |
| 1101 | if (assert) { |
| 1102 | m = dlm->node_num; |
| 1103 | mlog(0, "about to master %.*s here, this=%u\n", |
| 1104 | res->lockname.len, res->lockname.name, m); |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 1105 | ret = dlm_do_assert_master(dlm, res, mle->vote_map, 0); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1106 | if (ret) { |
| 1107 | /* This is a failure in the network path, |
| 1108 | * not in the response to the assert_master |
| 1109 | * (any nonzero response is a BUG on this node). |
| 1110 | * Most likely a socket just got disconnected |
| 1111 | * due to node death. */ |
| 1112 | mlog_errno(ret); |
| 1113 | } |
| 1114 | /* no longer need to restart lock mastery. |
| 1115 | * all living nodes have been contacted. */ |
| 1116 | ret = 0; |
| 1117 | } |
| 1118 | |
| 1119 | /* set the lockres owner */ |
| 1120 | spin_lock(&res->spinlock); |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 1121 | /* mastery reference obtained either during |
| 1122 | * assert_master_handler or in get_lock_resource */ |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1123 | dlm_change_lockres_owner(dlm, res, m); |
| 1124 | spin_unlock(&res->spinlock); |
| 1125 | |
| 1126 | leave: |
| 1127 | return ret; |
| 1128 | } |
| 1129 | |
| 1130 | struct dlm_bitmap_diff_iter |
| 1131 | { |
| 1132 | int curnode; |
| 1133 | unsigned long *orig_bm; |
| 1134 | unsigned long *cur_bm; |
| 1135 | unsigned long diff_bm[BITS_TO_LONGS(O2NM_MAX_NODES)]; |
| 1136 | }; |
| 1137 | |
| 1138 | enum dlm_node_state_change |
| 1139 | { |
| 1140 | NODE_DOWN = -1, |
| 1141 | NODE_NO_CHANGE = 0, |
| 1142 | NODE_UP |
| 1143 | }; |
| 1144 | |
| 1145 | static void dlm_bitmap_diff_iter_init(struct dlm_bitmap_diff_iter *iter, |
| 1146 | unsigned long *orig_bm, |
| 1147 | unsigned long *cur_bm) |
| 1148 | { |
| 1149 | unsigned long p1, p2; |
| 1150 | int i; |
| 1151 | |
| 1152 | iter->curnode = -1; |
| 1153 | iter->orig_bm = orig_bm; |
| 1154 | iter->cur_bm = cur_bm; |
| 1155 | |
| 1156 | for (i = 0; i < BITS_TO_LONGS(O2NM_MAX_NODES); i++) { |
| 1157 | p1 = *(iter->orig_bm + i); |
| 1158 | p2 = *(iter->cur_bm + i); |
| 1159 | iter->diff_bm[i] = (p1 & ~p2) | (p2 & ~p1); |
| 1160 | } |
| 1161 | } |
| 1162 | |
| 1163 | static int dlm_bitmap_diff_iter_next(struct dlm_bitmap_diff_iter *iter, |
| 1164 | enum dlm_node_state_change *state) |
| 1165 | { |
| 1166 | int bit; |
| 1167 | |
| 1168 | if (iter->curnode >= O2NM_MAX_NODES) |
| 1169 | return -ENOENT; |
| 1170 | |
| 1171 | bit = find_next_bit(iter->diff_bm, O2NM_MAX_NODES, |
| 1172 | iter->curnode+1); |
| 1173 | if (bit >= O2NM_MAX_NODES) { |
| 1174 | iter->curnode = O2NM_MAX_NODES; |
| 1175 | return -ENOENT; |
| 1176 | } |
| 1177 | |
| 1178 | /* if it was there in the original then this node died */ |
| 1179 | if (test_bit(bit, iter->orig_bm)) |
| 1180 | *state = NODE_DOWN; |
| 1181 | else |
| 1182 | *state = NODE_UP; |
| 1183 | |
| 1184 | iter->curnode = bit; |
| 1185 | return bit; |
| 1186 | } |
| 1187 | |
| 1188 | |
| 1189 | static int dlm_restart_lock_mastery(struct dlm_ctxt *dlm, |
| 1190 | struct dlm_lock_resource *res, |
| 1191 | struct dlm_master_list_entry *mle, |
| 1192 | int blocked) |
| 1193 | { |
| 1194 | struct dlm_bitmap_diff_iter bdi; |
| 1195 | enum dlm_node_state_change sc; |
| 1196 | int node; |
| 1197 | int ret = 0; |
| 1198 | |
| 1199 | mlog(0, "something happened such that the " |
| 1200 | "master process may need to be restarted!\n"); |
| 1201 | |
| 1202 | assert_spin_locked(&mle->spinlock); |
| 1203 | |
| 1204 | dlm_bitmap_diff_iter_init(&bdi, mle->vote_map, mle->node_map); |
| 1205 | node = dlm_bitmap_diff_iter_next(&bdi, &sc); |
| 1206 | while (node >= 0) { |
| 1207 | if (sc == NODE_UP) { |
Kurt Hackel | e2faea4 | 2006-01-12 14:24:55 -0800 | [diff] [blame] | 1208 | /* a node came up. clear any old vote from |
| 1209 | * the response map and set it in the vote map |
| 1210 | * then restart the mastery. */ |
| 1211 | mlog(ML_NOTICE, "node %d up while restarting\n", node); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1212 | |
| 1213 | /* redo the master request, but only for the new node */ |
| 1214 | mlog(0, "sending request to new node\n"); |
| 1215 | clear_bit(node, mle->response_map); |
| 1216 | set_bit(node, mle->vote_map); |
| 1217 | } else { |
| 1218 | mlog(ML_ERROR, "node down! %d\n", node); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1219 | if (blocked) { |
| 1220 | int lowest = find_next_bit(mle->maybe_map, |
| 1221 | O2NM_MAX_NODES, 0); |
| 1222 | |
| 1223 | /* act like it was never there */ |
| 1224 | clear_bit(node, mle->maybe_map); |
| 1225 | |
Kurt Hackel | e7e69eb | 2006-05-01 11:49:52 -0700 | [diff] [blame] | 1226 | if (node == lowest) { |
| 1227 | mlog(0, "expected master %u died" |
| 1228 | " while this node was blocked " |
| 1229 | "waiting on it!\n", node); |
| 1230 | lowest = find_next_bit(mle->maybe_map, |
| 1231 | O2NM_MAX_NODES, |
| 1232 | lowest+1); |
| 1233 | if (lowest < O2NM_MAX_NODES) { |
| 1234 | mlog(0, "%s:%.*s:still " |
| 1235 | "blocked. waiting on %u " |
| 1236 | "now\n", dlm->name, |
| 1237 | res->lockname.len, |
| 1238 | res->lockname.name, |
| 1239 | lowest); |
| 1240 | } else { |
| 1241 | /* mle is an MLE_BLOCK, but |
| 1242 | * there is now nothing left to |
| 1243 | * block on. we need to return |
| 1244 | * all the way back out and try |
| 1245 | * again with an MLE_MASTER. |
| 1246 | * dlm_do_local_recovery_cleanup |
| 1247 | * has already run, so the mle |
| 1248 | * refcount is ok */ |
| 1249 | mlog(0, "%s:%.*s: no " |
| 1250 | "longer blocking. try to " |
| 1251 | "master this here\n", |
| 1252 | dlm->name, |
| 1253 | res->lockname.len, |
| 1254 | res->lockname.name); |
| 1255 | mle->type = DLM_MLE_MASTER; |
| 1256 | mle->u.res = res; |
| 1257 | } |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1258 | } |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1259 | } |
| 1260 | |
Kurt Hackel | e7e69eb | 2006-05-01 11:49:52 -0700 | [diff] [blame] | 1261 | /* now blank out everything, as if we had never |
| 1262 | * contacted anyone */ |
| 1263 | memset(mle->maybe_map, 0, sizeof(mle->maybe_map)); |
| 1264 | memset(mle->response_map, 0, sizeof(mle->response_map)); |
| 1265 | /* reset the vote_map to the current node_map */ |
| 1266 | memcpy(mle->vote_map, mle->node_map, |
| 1267 | sizeof(mle->node_map)); |
| 1268 | /* put myself into the maybe map */ |
| 1269 | if (mle->type != DLM_MLE_BLOCK) |
| 1270 | set_bit(dlm->node_num, mle->maybe_map); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1271 | } |
| 1272 | ret = -EAGAIN; |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1273 | node = dlm_bitmap_diff_iter_next(&bdi, &sc); |
| 1274 | } |
| 1275 | return ret; |
| 1276 | } |
| 1277 | |
| 1278 | |
| 1279 | /* |
| 1280 | * DLM_MASTER_REQUEST_MSG |
| 1281 | * |
| 1282 | * returns: 0 on success, |
| 1283 | * -errno on a network error |
| 1284 | * |
| 1285 | * on error, the caller should assume the target node is "dead" |
| 1286 | * |
| 1287 | */ |
| 1288 | |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 1289 | static int dlm_do_master_request(struct dlm_lock_resource *res, |
| 1290 | struct dlm_master_list_entry *mle, int to) |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1291 | { |
| 1292 | struct dlm_ctxt *dlm = mle->dlm; |
| 1293 | struct dlm_master_request request; |
| 1294 | int ret, response=0, resend; |
| 1295 | |
| 1296 | memset(&request, 0, sizeof(request)); |
| 1297 | request.node_idx = dlm->node_num; |
| 1298 | |
| 1299 | BUG_ON(mle->type == DLM_MLE_MIGRATION); |
| 1300 | |
| 1301 | if (mle->type != DLM_MLE_MASTER) { |
| 1302 | request.namelen = mle->u.name.len; |
| 1303 | memcpy(request.name, mle->u.name.name, request.namelen); |
| 1304 | } else { |
| 1305 | request.namelen = mle->u.res->lockname.len; |
| 1306 | memcpy(request.name, mle->u.res->lockname.name, |
| 1307 | request.namelen); |
| 1308 | } |
| 1309 | |
| 1310 | again: |
| 1311 | ret = o2net_send_message(DLM_MASTER_REQUEST_MSG, dlm->key, &request, |
| 1312 | sizeof(request), to, &response); |
| 1313 | if (ret < 0) { |
| 1314 | if (ret == -ESRCH) { |
| 1315 | /* should never happen */ |
| 1316 | mlog(ML_ERROR, "TCP stack not ready!\n"); |
| 1317 | BUG(); |
| 1318 | } else if (ret == -EINVAL) { |
| 1319 | mlog(ML_ERROR, "bad args passed to o2net!\n"); |
| 1320 | BUG(); |
| 1321 | } else if (ret == -ENOMEM) { |
| 1322 | mlog(ML_ERROR, "out of memory while trying to send " |
| 1323 | "network message! retrying\n"); |
| 1324 | /* this is totally crude */ |
| 1325 | msleep(50); |
| 1326 | goto again; |
| 1327 | } else if (!dlm_is_host_down(ret)) { |
| 1328 | /* not a network error. bad. */ |
| 1329 | mlog_errno(ret); |
| 1330 | mlog(ML_ERROR, "unhandled error!"); |
| 1331 | BUG(); |
| 1332 | } |
| 1333 | /* all other errors should be network errors, |
| 1334 | * and likely indicate node death */ |
| 1335 | mlog(ML_ERROR, "link to %d went down!\n", to); |
| 1336 | goto out; |
| 1337 | } |
| 1338 | |
| 1339 | ret = 0; |
| 1340 | resend = 0; |
| 1341 | spin_lock(&mle->spinlock); |
| 1342 | switch (response) { |
| 1343 | case DLM_MASTER_RESP_YES: |
| 1344 | set_bit(to, mle->response_map); |
| 1345 | mlog(0, "node %u is the master, response=YES\n", to); |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 1346 | mlog(0, "%s:%.*s: master node %u now knows I have a " |
| 1347 | "reference\n", dlm->name, res->lockname.len, |
| 1348 | res->lockname.name, to); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1349 | mle->master = to; |
| 1350 | break; |
| 1351 | case DLM_MASTER_RESP_NO: |
| 1352 | mlog(0, "node %u not master, response=NO\n", to); |
| 1353 | set_bit(to, mle->response_map); |
| 1354 | break; |
| 1355 | case DLM_MASTER_RESP_MAYBE: |
| 1356 | mlog(0, "node %u not master, response=MAYBE\n", to); |
| 1357 | set_bit(to, mle->response_map); |
| 1358 | set_bit(to, mle->maybe_map); |
| 1359 | break; |
| 1360 | case DLM_MASTER_RESP_ERROR: |
| 1361 | mlog(0, "node %u hit an error, resending\n", to); |
| 1362 | resend = 1; |
| 1363 | response = 0; |
| 1364 | break; |
| 1365 | default: |
| 1366 | mlog(ML_ERROR, "bad response! %u\n", response); |
| 1367 | BUG(); |
| 1368 | } |
| 1369 | spin_unlock(&mle->spinlock); |
| 1370 | if (resend) { |
| 1371 | /* this is also totally crude */ |
| 1372 | msleep(50); |
| 1373 | goto again; |
| 1374 | } |
| 1375 | |
| 1376 | out: |
| 1377 | return ret; |
| 1378 | } |
| 1379 | |
| 1380 | /* |
| 1381 | * locks that can be taken here: |
| 1382 | * dlm->spinlock |
| 1383 | * res->spinlock |
| 1384 | * mle->spinlock |
| 1385 | * dlm->master_list |
| 1386 | * |
| 1387 | * if possible, TRIM THIS DOWN!!! |
| 1388 | */ |
Kurt Hackel | d74c980 | 2007-01-17 17:04:25 -0800 | [diff] [blame] | 1389 | int dlm_master_request_handler(struct o2net_msg *msg, u32 len, void *data, |
| 1390 | void **ret_data) |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1391 | { |
| 1392 | u8 response = DLM_MASTER_RESP_MAYBE; |
| 1393 | struct dlm_ctxt *dlm = data; |
Kurt Hackel | 9c6510a | 2006-03-02 18:09:26 -0800 | [diff] [blame] | 1394 | struct dlm_lock_resource *res = NULL; |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1395 | struct dlm_master_request *request = (struct dlm_master_request *) msg->buf; |
| 1396 | struct dlm_master_list_entry *mle = NULL, *tmpmle = NULL; |
| 1397 | char *name; |
Mark Fasheh | a3d3329 | 2006-03-09 17:55:56 -0800 | [diff] [blame] | 1398 | unsigned int namelen, hash; |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1399 | int found, ret; |
| 1400 | int set_maybe; |
Kurt Hackel | 9c6510a | 2006-03-02 18:09:26 -0800 | [diff] [blame] | 1401 | int dispatch_assert = 0; |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1402 | |
| 1403 | if (!dlm_grab(dlm)) |
| 1404 | return DLM_MASTER_RESP_NO; |
| 1405 | |
| 1406 | if (!dlm_domain_fully_joined(dlm)) { |
| 1407 | response = DLM_MASTER_RESP_NO; |
| 1408 | goto send_response; |
| 1409 | } |
| 1410 | |
| 1411 | name = request->name; |
| 1412 | namelen = request->namelen; |
Mark Fasheh | a3d3329 | 2006-03-09 17:55:56 -0800 | [diff] [blame] | 1413 | hash = dlm_lockid_hash(name, namelen); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1414 | |
| 1415 | if (namelen > DLM_LOCKID_NAME_MAX) { |
| 1416 | response = DLM_IVBUFLEN; |
| 1417 | goto send_response; |
| 1418 | } |
| 1419 | |
| 1420 | way_up_top: |
| 1421 | spin_lock(&dlm->spinlock); |
Mark Fasheh | a3d3329 | 2006-03-09 17:55:56 -0800 | [diff] [blame] | 1422 | res = __dlm_lookup_lockres(dlm, name, namelen, hash); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1423 | if (res) { |
| 1424 | spin_unlock(&dlm->spinlock); |
| 1425 | |
| 1426 | /* take care of the easy cases up front */ |
| 1427 | spin_lock(&res->spinlock); |
Kurt Hackel | 1cd04db | 2007-01-17 14:53:37 -0800 | [diff] [blame] | 1428 | if (res->state & (DLM_LOCK_RES_RECOVERING| |
| 1429 | DLM_LOCK_RES_MIGRATING)) { |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1430 | spin_unlock(&res->spinlock); |
| 1431 | mlog(0, "returning DLM_MASTER_RESP_ERROR since res is " |
Kurt Hackel | 1cd04db | 2007-01-17 14:53:37 -0800 | [diff] [blame] | 1432 | "being recovered/migrated\n"); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1433 | response = DLM_MASTER_RESP_ERROR; |
| 1434 | if (mle) |
| 1435 | kmem_cache_free(dlm_mle_cache, mle); |
| 1436 | goto send_response; |
| 1437 | } |
| 1438 | |
| 1439 | if (res->owner == dlm->node_num) { |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 1440 | mlog(0, "%s:%.*s: setting bit %u in refmap\n", |
| 1441 | dlm->name, namelen, name, request->node_idx); |
| 1442 | dlm_lockres_set_refmap_bit(request->node_idx, res); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1443 | spin_unlock(&res->spinlock); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1444 | response = DLM_MASTER_RESP_YES; |
| 1445 | if (mle) |
| 1446 | kmem_cache_free(dlm_mle_cache, mle); |
| 1447 | |
| 1448 | /* this node is the owner. |
| 1449 | * there is some extra work that needs to |
| 1450 | * happen now. the requesting node has |
| 1451 | * caused all nodes up to this one to |
| 1452 | * create mles. this node now needs to |
| 1453 | * go back and clean those up. */ |
Kurt Hackel | 9c6510a | 2006-03-02 18:09:26 -0800 | [diff] [blame] | 1454 | dispatch_assert = 1; |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1455 | goto send_response; |
| 1456 | } else if (res->owner != DLM_LOCK_RES_OWNER_UNKNOWN) { |
| 1457 | spin_unlock(&res->spinlock); |
| 1458 | // mlog(0, "node %u is the master\n", res->owner); |
| 1459 | response = DLM_MASTER_RESP_NO; |
| 1460 | if (mle) |
| 1461 | kmem_cache_free(dlm_mle_cache, mle); |
| 1462 | goto send_response; |
| 1463 | } |
| 1464 | |
| 1465 | /* ok, there is no owner. either this node is |
| 1466 | * being blocked, or it is actively trying to |
| 1467 | * master this lock. */ |
| 1468 | if (!(res->state & DLM_LOCK_RES_IN_PROGRESS)) { |
| 1469 | mlog(ML_ERROR, "lock with no owner should be " |
| 1470 | "in-progress!\n"); |
| 1471 | BUG(); |
| 1472 | } |
| 1473 | |
| 1474 | // mlog(0, "lockres is in progress...\n"); |
| 1475 | spin_lock(&dlm->master_lock); |
| 1476 | found = dlm_find_mle(dlm, &tmpmle, name, namelen); |
| 1477 | if (!found) { |
| 1478 | mlog(ML_ERROR, "no mle found for this lock!\n"); |
| 1479 | BUG(); |
| 1480 | } |
| 1481 | set_maybe = 1; |
| 1482 | spin_lock(&tmpmle->spinlock); |
| 1483 | if (tmpmle->type == DLM_MLE_BLOCK) { |
| 1484 | // mlog(0, "this node is waiting for " |
| 1485 | // "lockres to be mastered\n"); |
| 1486 | response = DLM_MASTER_RESP_NO; |
| 1487 | } else if (tmpmle->type == DLM_MLE_MIGRATION) { |
| 1488 | mlog(0, "node %u is master, but trying to migrate to " |
| 1489 | "node %u.\n", tmpmle->master, tmpmle->new_master); |
| 1490 | if (tmpmle->master == dlm->node_num) { |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1491 | mlog(ML_ERROR, "no owner on lockres, but this " |
| 1492 | "node is trying to migrate it to %u?!\n", |
| 1493 | tmpmle->new_master); |
| 1494 | BUG(); |
| 1495 | } else { |
| 1496 | /* the real master can respond on its own */ |
| 1497 | response = DLM_MASTER_RESP_NO; |
| 1498 | } |
| 1499 | } else if (tmpmle->master != DLM_LOCK_RES_OWNER_UNKNOWN) { |
| 1500 | set_maybe = 0; |
Kurt Hackel | 9c6510a | 2006-03-02 18:09:26 -0800 | [diff] [blame] | 1501 | if (tmpmle->master == dlm->node_num) { |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1502 | response = DLM_MASTER_RESP_YES; |
Kurt Hackel | 9c6510a | 2006-03-02 18:09:26 -0800 | [diff] [blame] | 1503 | /* this node will be the owner. |
| 1504 | * go back and clean the mles on any |
| 1505 | * other nodes */ |
| 1506 | dispatch_assert = 1; |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 1507 | dlm_lockres_set_refmap_bit(request->node_idx, res); |
| 1508 | mlog(0, "%s:%.*s: setting bit %u in refmap\n", |
| 1509 | dlm->name, namelen, name, |
| 1510 | request->node_idx); |
Kurt Hackel | 9c6510a | 2006-03-02 18:09:26 -0800 | [diff] [blame] | 1511 | } else |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1512 | response = DLM_MASTER_RESP_NO; |
| 1513 | } else { |
| 1514 | // mlog(0, "this node is attempting to " |
| 1515 | // "master lockres\n"); |
| 1516 | response = DLM_MASTER_RESP_MAYBE; |
| 1517 | } |
| 1518 | if (set_maybe) |
| 1519 | set_bit(request->node_idx, tmpmle->maybe_map); |
| 1520 | spin_unlock(&tmpmle->spinlock); |
| 1521 | |
| 1522 | spin_unlock(&dlm->master_lock); |
| 1523 | spin_unlock(&res->spinlock); |
| 1524 | |
| 1525 | /* keep the mle attached to heartbeat events */ |
| 1526 | dlm_put_mle(tmpmle); |
| 1527 | if (mle) |
| 1528 | kmem_cache_free(dlm_mle_cache, mle); |
| 1529 | goto send_response; |
| 1530 | } |
| 1531 | |
| 1532 | /* |
| 1533 | * lockres doesn't exist on this node |
| 1534 | * if there is an MLE_BLOCK, return NO |
| 1535 | * if there is an MLE_MASTER, return MAYBE |
| 1536 | * otherwise, add an MLE_BLOCK, return NO |
| 1537 | */ |
| 1538 | spin_lock(&dlm->master_lock); |
| 1539 | found = dlm_find_mle(dlm, &tmpmle, name, namelen); |
| 1540 | if (!found) { |
| 1541 | /* this lockid has never been seen on this node yet */ |
| 1542 | // mlog(0, "no mle found\n"); |
| 1543 | if (!mle) { |
| 1544 | spin_unlock(&dlm->master_lock); |
| 1545 | spin_unlock(&dlm->spinlock); |
| 1546 | |
| 1547 | mle = (struct dlm_master_list_entry *) |
Kurt Hackel | ad8100e | 2006-05-01 14:25:21 -0700 | [diff] [blame] | 1548 | kmem_cache_alloc(dlm_mle_cache, GFP_NOFS); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1549 | if (!mle) { |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1550 | response = DLM_MASTER_RESP_ERROR; |
Kurt Hackel | 9c6510a | 2006-03-02 18:09:26 -0800 | [diff] [blame] | 1551 | mlog_errno(-ENOMEM); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1552 | goto send_response; |
| 1553 | } |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1554 | goto way_up_top; |
| 1555 | } |
| 1556 | |
| 1557 | // mlog(0, "this is second time thru, already allocated, " |
| 1558 | // "add the block.\n"); |
Kurt Hackel | 41b8c8a | 2006-04-27 19:00:26 -0700 | [diff] [blame] | 1559 | dlm_init_mle(mle, DLM_MLE_BLOCK, dlm, NULL, name, namelen); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1560 | set_bit(request->node_idx, mle->maybe_map); |
| 1561 | list_add(&mle->list, &dlm->master_list); |
| 1562 | response = DLM_MASTER_RESP_NO; |
| 1563 | } else { |
| 1564 | // mlog(0, "mle was found\n"); |
| 1565 | set_maybe = 1; |
| 1566 | spin_lock(&tmpmle->spinlock); |
Kurt Hackel | 9c6510a | 2006-03-02 18:09:26 -0800 | [diff] [blame] | 1567 | if (tmpmle->master == dlm->node_num) { |
| 1568 | mlog(ML_ERROR, "no lockres, but an mle with this node as master!\n"); |
| 1569 | BUG(); |
| 1570 | } |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1571 | if (tmpmle->type == DLM_MLE_BLOCK) |
| 1572 | response = DLM_MASTER_RESP_NO; |
| 1573 | else if (tmpmle->type == DLM_MLE_MIGRATION) { |
| 1574 | mlog(0, "migration mle was found (%u->%u)\n", |
| 1575 | tmpmle->master, tmpmle->new_master); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1576 | /* real master can respond on its own */ |
| 1577 | response = DLM_MASTER_RESP_NO; |
Kurt Hackel | 9c6510a | 2006-03-02 18:09:26 -0800 | [diff] [blame] | 1578 | } else |
| 1579 | response = DLM_MASTER_RESP_MAYBE; |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1580 | if (set_maybe) |
| 1581 | set_bit(request->node_idx, tmpmle->maybe_map); |
| 1582 | spin_unlock(&tmpmle->spinlock); |
| 1583 | } |
| 1584 | spin_unlock(&dlm->master_lock); |
| 1585 | spin_unlock(&dlm->spinlock); |
| 1586 | |
| 1587 | if (found) { |
| 1588 | /* keep the mle attached to heartbeat events */ |
| 1589 | dlm_put_mle(tmpmle); |
| 1590 | } |
| 1591 | send_response: |
Sunil Mushran | b31cfc0 | 2008-03-01 14:04:22 -0800 | [diff] [blame] | 1592 | /* |
| 1593 | * __dlm_lookup_lockres() grabbed a reference to this lockres. |
| 1594 | * The reference is released by dlm_assert_master_worker() under |
| 1595 | * the call to dlm_dispatch_assert_master(). If |
| 1596 | * dlm_assert_master_worker() isn't called, we drop it here. |
| 1597 | */ |
Kurt Hackel | 9c6510a | 2006-03-02 18:09:26 -0800 | [diff] [blame] | 1598 | if (dispatch_assert) { |
| 1599 | if (response != DLM_MASTER_RESP_YES) |
| 1600 | mlog(ML_ERROR, "invalid response %d\n", response); |
| 1601 | if (!res) { |
| 1602 | mlog(ML_ERROR, "bad lockres while trying to assert!\n"); |
| 1603 | BUG(); |
| 1604 | } |
| 1605 | mlog(0, "%u is the owner of %.*s, cleaning everyone else\n", |
| 1606 | dlm->node_num, res->lockname.len, res->lockname.name); |
| 1607 | ret = dlm_dispatch_assert_master(dlm, res, 0, request->node_idx, |
| 1608 | DLM_ASSERT_MASTER_MLE_CLEANUP); |
| 1609 | if (ret < 0) { |
| 1610 | mlog(ML_ERROR, "failed to dispatch assert master work\n"); |
| 1611 | response = DLM_MASTER_RESP_ERROR; |
Sunil Mushran | b31cfc0 | 2008-03-01 14:04:22 -0800 | [diff] [blame] | 1612 | dlm_lockres_put(res); |
Kurt Hackel | 9c6510a | 2006-03-02 18:09:26 -0800 | [diff] [blame] | 1613 | } |
Sunil Mushran | b31cfc0 | 2008-03-01 14:04:22 -0800 | [diff] [blame] | 1614 | } else { |
| 1615 | if (res) |
| 1616 | dlm_lockres_put(res); |
Kurt Hackel | 9c6510a | 2006-03-02 18:09:26 -0800 | [diff] [blame] | 1617 | } |
| 1618 | |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1619 | dlm_put(dlm); |
| 1620 | return response; |
| 1621 | } |
| 1622 | |
| 1623 | /* |
| 1624 | * DLM_ASSERT_MASTER_MSG |
| 1625 | */ |
| 1626 | |
| 1627 | |
| 1628 | /* |
| 1629 | * NOTE: this can be used for debugging |
| 1630 | * can periodically run all locks owned by this node |
| 1631 | * and re-assert across the cluster... |
| 1632 | */ |
Adrian Bunk | 05488bb | 2008-02-17 10:20:41 +0200 | [diff] [blame] | 1633 | static int dlm_do_assert_master(struct dlm_ctxt *dlm, |
| 1634 | struct dlm_lock_resource *res, |
| 1635 | void *nodemap, u32 flags) |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1636 | { |
| 1637 | struct dlm_assert_master assert; |
| 1638 | int to, tmpret; |
| 1639 | struct dlm_node_iter iter; |
| 1640 | int ret = 0; |
Kurt Hackel | 9c6510a | 2006-03-02 18:09:26 -0800 | [diff] [blame] | 1641 | int reassert; |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 1642 | const char *lockname = res->lockname.name; |
| 1643 | unsigned int namelen = res->lockname.len; |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1644 | |
| 1645 | BUG_ON(namelen > O2NM_MAX_NAME_LEN); |
Sunil Mushran | f3f8546 | 2007-01-29 15:19:16 -0800 | [diff] [blame] | 1646 | |
| 1647 | spin_lock(&res->spinlock); |
| 1648 | res->state |= DLM_LOCK_RES_SETREF_INPROG; |
| 1649 | spin_unlock(&res->spinlock); |
| 1650 | |
Kurt Hackel | 9c6510a | 2006-03-02 18:09:26 -0800 | [diff] [blame] | 1651 | again: |
| 1652 | reassert = 0; |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1653 | |
| 1654 | /* note that if this nodemap is empty, it returns 0 */ |
| 1655 | dlm_node_iter_init(nodemap, &iter); |
| 1656 | while ((to = dlm_node_iter_next(&iter)) >= 0) { |
| 1657 | int r = 0; |
Kurt Hackel | a9ee4c8 | 2006-04-27 19:26:15 -0700 | [diff] [blame] | 1658 | struct dlm_master_list_entry *mle = NULL; |
| 1659 | |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1660 | mlog(0, "sending assert master to %d (%.*s)\n", to, |
| 1661 | namelen, lockname); |
| 1662 | memset(&assert, 0, sizeof(assert)); |
| 1663 | assert.node_idx = dlm->node_num; |
| 1664 | assert.namelen = namelen; |
| 1665 | memcpy(assert.name, lockname, namelen); |
| 1666 | assert.flags = cpu_to_be32(flags); |
| 1667 | |
| 1668 | tmpret = o2net_send_message(DLM_ASSERT_MASTER_MSG, dlm->key, |
| 1669 | &assert, sizeof(assert), to, &r); |
| 1670 | if (tmpret < 0) { |
Kurt Hackel | 3b3b84a | 2006-05-01 14:31:37 -0700 | [diff] [blame] | 1671 | mlog(0, "assert_master returned %d!\n", tmpret); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1672 | if (!dlm_is_host_down(tmpret)) { |
Kurt Hackel | 3b3b84a | 2006-05-01 14:31:37 -0700 | [diff] [blame] | 1673 | mlog(ML_ERROR, "unhandled error=%d!\n", tmpret); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1674 | BUG(); |
| 1675 | } |
| 1676 | /* a node died. finish out the rest of the nodes. */ |
Kurt Hackel | 3b3b84a | 2006-05-01 14:31:37 -0700 | [diff] [blame] | 1677 | mlog(0, "link to %d went down!\n", to); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1678 | /* any nonzero status return will do */ |
| 1679 | ret = tmpret; |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 1680 | r = 0; |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1681 | } else if (r < 0) { |
| 1682 | /* ok, something horribly messed. kill thyself. */ |
| 1683 | mlog(ML_ERROR,"during assert master of %.*s to %u, " |
| 1684 | "got %d.\n", namelen, lockname, to, r); |
Kurt Hackel | a9ee4c8 | 2006-04-27 19:26:15 -0700 | [diff] [blame] | 1685 | spin_lock(&dlm->spinlock); |
| 1686 | spin_lock(&dlm->master_lock); |
| 1687 | if (dlm_find_mle(dlm, &mle, (char *)lockname, |
| 1688 | namelen)) { |
| 1689 | dlm_print_one_mle(mle); |
| 1690 | __dlm_put_mle(mle); |
| 1691 | } |
| 1692 | spin_unlock(&dlm->master_lock); |
| 1693 | spin_unlock(&dlm->spinlock); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1694 | BUG(); |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 1695 | } |
| 1696 | |
| 1697 | if (r & DLM_ASSERT_RESPONSE_REASSERT && |
| 1698 | !(r & DLM_ASSERT_RESPONSE_MASTERY_REF)) { |
| 1699 | mlog(ML_ERROR, "%.*s: very strange, " |
| 1700 | "master MLE but no lockres on %u\n", |
| 1701 | namelen, lockname, to); |
| 1702 | } |
| 1703 | |
| 1704 | if (r & DLM_ASSERT_RESPONSE_REASSERT) { |
Kurt Hackel | 9c6510a | 2006-03-02 18:09:26 -0800 | [diff] [blame] | 1705 | mlog(0, "%.*s: node %u create mles on other " |
| 1706 | "nodes and requests a re-assert\n", |
| 1707 | namelen, lockname, to); |
| 1708 | reassert = 1; |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1709 | } |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 1710 | if (r & DLM_ASSERT_RESPONSE_MASTERY_REF) { |
| 1711 | mlog(0, "%.*s: node %u has a reference to this " |
| 1712 | "lockres, set the bit in the refmap\n", |
| 1713 | namelen, lockname, to); |
| 1714 | spin_lock(&res->spinlock); |
| 1715 | dlm_lockres_set_refmap_bit(to, res); |
| 1716 | spin_unlock(&res->spinlock); |
| 1717 | } |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1718 | } |
| 1719 | |
Kurt Hackel | 9c6510a | 2006-03-02 18:09:26 -0800 | [diff] [blame] | 1720 | if (reassert) |
| 1721 | goto again; |
| 1722 | |
Sunil Mushran | f3f8546 | 2007-01-29 15:19:16 -0800 | [diff] [blame] | 1723 | spin_lock(&res->spinlock); |
| 1724 | res->state &= ~DLM_LOCK_RES_SETREF_INPROG; |
| 1725 | spin_unlock(&res->spinlock); |
| 1726 | wake_up(&res->wq); |
| 1727 | |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1728 | return ret; |
| 1729 | } |
| 1730 | |
| 1731 | /* |
| 1732 | * locks that can be taken here: |
| 1733 | * dlm->spinlock |
| 1734 | * res->spinlock |
| 1735 | * mle->spinlock |
| 1736 | * dlm->master_list |
| 1737 | * |
| 1738 | * if possible, TRIM THIS DOWN!!! |
| 1739 | */ |
Kurt Hackel | d74c980 | 2007-01-17 17:04:25 -0800 | [diff] [blame] | 1740 | int dlm_assert_master_handler(struct o2net_msg *msg, u32 len, void *data, |
| 1741 | void **ret_data) |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1742 | { |
| 1743 | struct dlm_ctxt *dlm = data; |
| 1744 | struct dlm_master_list_entry *mle = NULL; |
| 1745 | struct dlm_assert_master *assert = (struct dlm_assert_master *)msg->buf; |
| 1746 | struct dlm_lock_resource *res = NULL; |
| 1747 | char *name; |
Mark Fasheh | a3d3329 | 2006-03-09 17:55:56 -0800 | [diff] [blame] | 1748 | unsigned int namelen, hash; |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1749 | u32 flags; |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 1750 | int master_request = 0, have_lockres_ref = 0; |
Kurt Hackel | 9c6510a | 2006-03-02 18:09:26 -0800 | [diff] [blame] | 1751 | int ret = 0; |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1752 | |
| 1753 | if (!dlm_grab(dlm)) |
| 1754 | return 0; |
| 1755 | |
| 1756 | name = assert->name; |
| 1757 | namelen = assert->namelen; |
Mark Fasheh | a3d3329 | 2006-03-09 17:55:56 -0800 | [diff] [blame] | 1758 | hash = dlm_lockid_hash(name, namelen); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1759 | flags = be32_to_cpu(assert->flags); |
| 1760 | |
| 1761 | if (namelen > DLM_LOCKID_NAME_MAX) { |
| 1762 | mlog(ML_ERROR, "Invalid name length!"); |
| 1763 | goto done; |
| 1764 | } |
| 1765 | |
| 1766 | spin_lock(&dlm->spinlock); |
| 1767 | |
| 1768 | if (flags) |
| 1769 | mlog(0, "assert_master with flags: %u\n", flags); |
| 1770 | |
| 1771 | /* find the MLE */ |
| 1772 | spin_lock(&dlm->master_lock); |
| 1773 | if (!dlm_find_mle(dlm, &mle, name, namelen)) { |
| 1774 | /* not an error, could be master just re-asserting */ |
| 1775 | mlog(0, "just got an assert_master from %u, but no " |
| 1776 | "MLE for it! (%.*s)\n", assert->node_idx, |
| 1777 | namelen, name); |
| 1778 | } else { |
| 1779 | int bit = find_next_bit (mle->maybe_map, O2NM_MAX_NODES, 0); |
| 1780 | if (bit >= O2NM_MAX_NODES) { |
| 1781 | /* not necessarily an error, though less likely. |
| 1782 | * could be master just re-asserting. */ |
Kurt Hackel | aa85235 | 2006-04-27 19:04:49 -0700 | [diff] [blame] | 1783 | mlog(0, "no bits set in the maybe_map, but %u " |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1784 | "is asserting! (%.*s)\n", assert->node_idx, |
| 1785 | namelen, name); |
| 1786 | } else if (bit != assert->node_idx) { |
| 1787 | if (flags & DLM_ASSERT_MASTER_MLE_CLEANUP) { |
| 1788 | mlog(0, "master %u was found, %u should " |
| 1789 | "back off\n", assert->node_idx, bit); |
| 1790 | } else { |
| 1791 | /* with the fix for bug 569, a higher node |
| 1792 | * number winning the mastery will respond |
| 1793 | * YES to mastery requests, but this node |
| 1794 | * had no way of knowing. let it pass. */ |
Kurt Hackel | aa85235 | 2006-04-27 19:04:49 -0700 | [diff] [blame] | 1795 | mlog(0, "%u is the lowest node, " |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1796 | "%u is asserting. (%.*s) %u must " |
| 1797 | "have begun after %u won.\n", bit, |
| 1798 | assert->node_idx, namelen, name, bit, |
| 1799 | assert->node_idx); |
| 1800 | } |
| 1801 | } |
Kurt Hackel | 2d1a868 | 2006-04-27 19:01:35 -0700 | [diff] [blame] | 1802 | if (mle->type == DLM_MLE_MIGRATION) { |
| 1803 | if (flags & DLM_ASSERT_MASTER_MLE_CLEANUP) { |
| 1804 | mlog(0, "%s:%.*s: got cleanup assert" |
| 1805 | " from %u for migration\n", |
| 1806 | dlm->name, namelen, name, |
| 1807 | assert->node_idx); |
| 1808 | } else if (!(flags & DLM_ASSERT_MASTER_FINISH_MIGRATION)) { |
| 1809 | mlog(0, "%s:%.*s: got unrelated assert" |
| 1810 | " from %u for migration, ignoring\n", |
| 1811 | dlm->name, namelen, name, |
| 1812 | assert->node_idx); |
| 1813 | __dlm_put_mle(mle); |
| 1814 | spin_unlock(&dlm->master_lock); |
| 1815 | spin_unlock(&dlm->spinlock); |
| 1816 | goto done; |
| 1817 | } |
| 1818 | } |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1819 | } |
| 1820 | spin_unlock(&dlm->master_lock); |
| 1821 | |
| 1822 | /* ok everything checks out with the MLE |
| 1823 | * now check to see if there is a lockres */ |
Mark Fasheh | a3d3329 | 2006-03-09 17:55:56 -0800 | [diff] [blame] | 1824 | res = __dlm_lookup_lockres(dlm, name, namelen, hash); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1825 | if (res) { |
| 1826 | spin_lock(&res->spinlock); |
| 1827 | if (res->state & DLM_LOCK_RES_RECOVERING) { |
| 1828 | mlog(ML_ERROR, "%u asserting but %.*s is " |
| 1829 | "RECOVERING!\n", assert->node_idx, namelen, name); |
| 1830 | goto kill; |
| 1831 | } |
| 1832 | if (!mle) { |
Kurt Hackel | dc2ed19 | 2006-04-27 19:03:18 -0700 | [diff] [blame] | 1833 | if (res->owner != DLM_LOCK_RES_OWNER_UNKNOWN && |
| 1834 | res->owner != assert->node_idx) { |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1835 | mlog(ML_ERROR, "assert_master from " |
| 1836 | "%u, but current owner is " |
| 1837 | "%u! (%.*s)\n", |
| 1838 | assert->node_idx, res->owner, |
| 1839 | namelen, name); |
| 1840 | goto kill; |
| 1841 | } |
| 1842 | } else if (mle->type != DLM_MLE_MIGRATION) { |
| 1843 | if (res->owner != DLM_LOCK_RES_OWNER_UNKNOWN) { |
| 1844 | /* owner is just re-asserting */ |
| 1845 | if (res->owner == assert->node_idx) { |
| 1846 | mlog(0, "owner %u re-asserting on " |
| 1847 | "lock %.*s\n", assert->node_idx, |
| 1848 | namelen, name); |
| 1849 | goto ok; |
| 1850 | } |
| 1851 | mlog(ML_ERROR, "got assert_master from " |
| 1852 | "node %u, but %u is the owner! " |
| 1853 | "(%.*s)\n", assert->node_idx, |
| 1854 | res->owner, namelen, name); |
| 1855 | goto kill; |
| 1856 | } |
| 1857 | if (!(res->state & DLM_LOCK_RES_IN_PROGRESS)) { |
| 1858 | mlog(ML_ERROR, "got assert from %u, but lock " |
| 1859 | "with no owner should be " |
| 1860 | "in-progress! (%.*s)\n", |
| 1861 | assert->node_idx, |
| 1862 | namelen, name); |
| 1863 | goto kill; |
| 1864 | } |
| 1865 | } else /* mle->type == DLM_MLE_MIGRATION */ { |
| 1866 | /* should only be getting an assert from new master */ |
| 1867 | if (assert->node_idx != mle->new_master) { |
| 1868 | mlog(ML_ERROR, "got assert from %u, but " |
| 1869 | "new master is %u, and old master " |
| 1870 | "was %u (%.*s)\n", |
| 1871 | assert->node_idx, mle->new_master, |
| 1872 | mle->master, namelen, name); |
| 1873 | goto kill; |
| 1874 | } |
| 1875 | |
| 1876 | } |
| 1877 | ok: |
| 1878 | spin_unlock(&res->spinlock); |
| 1879 | } |
| 1880 | spin_unlock(&dlm->spinlock); |
| 1881 | |
| 1882 | // mlog(0, "woo! got an assert_master from node %u!\n", |
| 1883 | // assert->node_idx); |
| 1884 | if (mle) { |
Kurt Hackel | 9c6510a | 2006-03-02 18:09:26 -0800 | [diff] [blame] | 1885 | int extra_ref = 0; |
| 1886 | int nn = -1; |
Kurt Hackel | a2bf047 | 2006-04-27 18:51:26 -0700 | [diff] [blame] | 1887 | int rr, err = 0; |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1888 | |
| 1889 | spin_lock(&mle->spinlock); |
Kurt Hackel | 9c6510a | 2006-03-02 18:09:26 -0800 | [diff] [blame] | 1890 | if (mle->type == DLM_MLE_BLOCK || mle->type == DLM_MLE_MIGRATION) |
| 1891 | extra_ref = 1; |
| 1892 | else { |
| 1893 | /* MASTER mle: if any bits set in the response map |
| 1894 | * then the calling node needs to re-assert to clear |
| 1895 | * up nodes that this node contacted */ |
| 1896 | while ((nn = find_next_bit (mle->response_map, O2NM_MAX_NODES, |
| 1897 | nn+1)) < O2NM_MAX_NODES) { |
| 1898 | if (nn != dlm->node_num && nn != assert->node_idx) |
| 1899 | master_request = 1; |
| 1900 | } |
| 1901 | } |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1902 | mle->master = assert->node_idx; |
| 1903 | atomic_set(&mle->woken, 1); |
| 1904 | wake_up(&mle->wq); |
| 1905 | spin_unlock(&mle->spinlock); |
| 1906 | |
Kurt Hackel | a2bf047 | 2006-04-27 18:51:26 -0700 | [diff] [blame] | 1907 | if (res) { |
Kurt Hackel | a6fa364 | 2007-01-17 14:59:12 -0800 | [diff] [blame] | 1908 | int wake = 0; |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1909 | spin_lock(&res->spinlock); |
Kurt Hackel | a2bf047 | 2006-04-27 18:51:26 -0700 | [diff] [blame] | 1910 | if (mle->type == DLM_MLE_MIGRATION) { |
| 1911 | mlog(0, "finishing off migration of lockres %.*s, " |
| 1912 | "from %u to %u\n", |
| 1913 | res->lockname.len, res->lockname.name, |
| 1914 | dlm->node_num, mle->new_master); |
| 1915 | res->state &= ~DLM_LOCK_RES_MIGRATING; |
Kurt Hackel | a6fa364 | 2007-01-17 14:59:12 -0800 | [diff] [blame] | 1916 | wake = 1; |
Kurt Hackel | a2bf047 | 2006-04-27 18:51:26 -0700 | [diff] [blame] | 1917 | dlm_change_lockres_owner(dlm, res, mle->new_master); |
| 1918 | BUG_ON(res->state & DLM_LOCK_RES_DIRTY); |
| 1919 | } else { |
| 1920 | dlm_change_lockres_owner(dlm, res, mle->master); |
| 1921 | } |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1922 | spin_unlock(&res->spinlock); |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 1923 | have_lockres_ref = 1; |
Kurt Hackel | a6fa364 | 2007-01-17 14:59:12 -0800 | [diff] [blame] | 1924 | if (wake) |
| 1925 | wake_up(&res->wq); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1926 | } |
Kurt Hackel | a2bf047 | 2006-04-27 18:51:26 -0700 | [diff] [blame] | 1927 | |
| 1928 | /* master is known, detach if not already detached. |
| 1929 | * ensures that only one assert_master call will happen |
| 1930 | * on this mle. */ |
| 1931 | spin_lock(&dlm->spinlock); |
| 1932 | spin_lock(&dlm->master_lock); |
| 1933 | |
| 1934 | rr = atomic_read(&mle->mle_refs.refcount); |
| 1935 | if (mle->inuse > 0) { |
| 1936 | if (extra_ref && rr < 3) |
| 1937 | err = 1; |
| 1938 | else if (!extra_ref && rr < 2) |
| 1939 | err = 1; |
| 1940 | } else { |
| 1941 | if (extra_ref && rr < 2) |
| 1942 | err = 1; |
| 1943 | else if (!extra_ref && rr < 1) |
| 1944 | err = 1; |
| 1945 | } |
| 1946 | if (err) { |
| 1947 | mlog(ML_ERROR, "%s:%.*s: got assert master from %u " |
| 1948 | "that will mess up this node, refs=%d, extra=%d, " |
| 1949 | "inuse=%d\n", dlm->name, namelen, name, |
| 1950 | assert->node_idx, rr, extra_ref, mle->inuse); |
| 1951 | dlm_print_one_mle(mle); |
| 1952 | } |
| 1953 | list_del_init(&mle->list); |
| 1954 | __dlm_mle_detach_hb_events(dlm, mle); |
| 1955 | __dlm_put_mle(mle); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1956 | if (extra_ref) { |
| 1957 | /* the assert master message now balances the extra |
| 1958 | * ref given by the master / migration request message. |
| 1959 | * if this is the last put, it will be removed |
| 1960 | * from the list. */ |
Kurt Hackel | a2bf047 | 2006-04-27 18:51:26 -0700 | [diff] [blame] | 1961 | __dlm_put_mle(mle); |
| 1962 | } |
| 1963 | spin_unlock(&dlm->master_lock); |
| 1964 | spin_unlock(&dlm->spinlock); |
| 1965 | } else if (res) { |
| 1966 | if (res->owner != assert->node_idx) { |
| 1967 | mlog(0, "assert_master from %u, but current " |
| 1968 | "owner is %u (%.*s), no mle\n", assert->node_idx, |
| 1969 | res->owner, namelen, name); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1970 | } |
| 1971 | } |
| 1972 | |
| 1973 | done: |
Kurt Hackel | 9c6510a | 2006-03-02 18:09:26 -0800 | [diff] [blame] | 1974 | ret = 0; |
Kurt Hackel | 3b8118c | 2007-01-17 17:05:53 -0800 | [diff] [blame] | 1975 | if (res) { |
| 1976 | spin_lock(&res->spinlock); |
| 1977 | res->state |= DLM_LOCK_RES_SETREF_INPROG; |
| 1978 | spin_unlock(&res->spinlock); |
| 1979 | *ret_data = (void *)res; |
| 1980 | } |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1981 | dlm_put(dlm); |
Kurt Hackel | 9c6510a | 2006-03-02 18:09:26 -0800 | [diff] [blame] | 1982 | if (master_request) { |
| 1983 | mlog(0, "need to tell master to reassert\n"); |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 1984 | /* positive. negative would shoot down the node. */ |
| 1985 | ret |= DLM_ASSERT_RESPONSE_REASSERT; |
| 1986 | if (!have_lockres_ref) { |
| 1987 | mlog(ML_ERROR, "strange, got assert from %u, MASTER " |
| 1988 | "mle present here for %s:%.*s, but no lockres!\n", |
| 1989 | assert->node_idx, dlm->name, namelen, name); |
| 1990 | } |
| 1991 | } |
| 1992 | if (have_lockres_ref) { |
| 1993 | /* let the master know we have a reference to the lockres */ |
| 1994 | ret |= DLM_ASSERT_RESPONSE_MASTERY_REF; |
| 1995 | mlog(0, "%s:%.*s: got assert from %u, need a ref\n", |
| 1996 | dlm->name, namelen, name, assert->node_idx); |
Kurt Hackel | 9c6510a | 2006-03-02 18:09:26 -0800 | [diff] [blame] | 1997 | } |
| 1998 | return ret; |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 1999 | |
| 2000 | kill: |
| 2001 | /* kill the caller! */ |
Kurt Hackel | a9ee4c8 | 2006-04-27 19:26:15 -0700 | [diff] [blame] | 2002 | mlog(ML_ERROR, "Bad message received from another node. Dumping state " |
| 2003 | "and killing the other node now! This node is OK and can continue.\n"); |
| 2004 | __dlm_print_one_lock_resource(res); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 2005 | spin_unlock(&res->spinlock); |
| 2006 | spin_unlock(&dlm->spinlock); |
Kurt Hackel | 3b8118c | 2007-01-17 17:05:53 -0800 | [diff] [blame] | 2007 | *ret_data = (void *)res; |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 2008 | dlm_put(dlm); |
| 2009 | return -EINVAL; |
| 2010 | } |
| 2011 | |
Kurt Hackel | 3b8118c | 2007-01-17 17:05:53 -0800 | [diff] [blame] | 2012 | void dlm_assert_master_post_handler(int status, void *data, void *ret_data) |
| 2013 | { |
| 2014 | struct dlm_lock_resource *res = (struct dlm_lock_resource *)ret_data; |
| 2015 | |
| 2016 | if (ret_data) { |
| 2017 | spin_lock(&res->spinlock); |
| 2018 | res->state &= ~DLM_LOCK_RES_SETREF_INPROG; |
| 2019 | spin_unlock(&res->spinlock); |
| 2020 | wake_up(&res->wq); |
| 2021 | dlm_lockres_put(res); |
| 2022 | } |
| 2023 | return; |
| 2024 | } |
| 2025 | |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 2026 | int dlm_dispatch_assert_master(struct dlm_ctxt *dlm, |
| 2027 | struct dlm_lock_resource *res, |
| 2028 | int ignore_higher, u8 request_from, u32 flags) |
| 2029 | { |
| 2030 | struct dlm_work_item *item; |
Robert P. J. Day | cd86128 | 2006-12-13 00:34:52 -0800 | [diff] [blame] | 2031 | item = kzalloc(sizeof(*item), GFP_NOFS); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 2032 | if (!item) |
| 2033 | return -ENOMEM; |
| 2034 | |
| 2035 | |
| 2036 | /* queue up work for dlm_assert_master_worker */ |
| 2037 | dlm_grab(dlm); /* get an extra ref for the work item */ |
| 2038 | dlm_init_work_item(dlm, item, dlm_assert_master_worker, NULL); |
| 2039 | item->u.am.lockres = res; /* already have a ref */ |
| 2040 | /* can optionally ignore node numbers higher than this node */ |
| 2041 | item->u.am.ignore_higher = ignore_higher; |
| 2042 | item->u.am.request_from = request_from; |
| 2043 | item->u.am.flags = flags; |
| 2044 | |
Kurt Hackel | 9c6510a | 2006-03-02 18:09:26 -0800 | [diff] [blame] | 2045 | if (ignore_higher) |
| 2046 | mlog(0, "IGNORE HIGHER: %.*s\n", res->lockname.len, |
| 2047 | res->lockname.name); |
| 2048 | |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 2049 | spin_lock(&dlm->work_lock); |
| 2050 | list_add_tail(&item->list, &dlm->work_list); |
| 2051 | spin_unlock(&dlm->work_lock); |
| 2052 | |
Kurt Hackel | 3156d26 | 2006-05-01 14:39:29 -0700 | [diff] [blame] | 2053 | queue_work(dlm->dlm_worker, &dlm->dispatched_work); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 2054 | return 0; |
| 2055 | } |
| 2056 | |
| 2057 | static void dlm_assert_master_worker(struct dlm_work_item *item, void *data) |
| 2058 | { |
| 2059 | struct dlm_ctxt *dlm = data; |
| 2060 | int ret = 0; |
| 2061 | struct dlm_lock_resource *res; |
| 2062 | unsigned long nodemap[BITS_TO_LONGS(O2NM_MAX_NODES)]; |
| 2063 | int ignore_higher; |
| 2064 | int bit; |
| 2065 | u8 request_from; |
| 2066 | u32 flags; |
| 2067 | |
| 2068 | dlm = item->dlm; |
| 2069 | res = item->u.am.lockres; |
| 2070 | ignore_higher = item->u.am.ignore_higher; |
| 2071 | request_from = item->u.am.request_from; |
| 2072 | flags = item->u.am.flags; |
| 2073 | |
| 2074 | spin_lock(&dlm->spinlock); |
| 2075 | memcpy(nodemap, dlm->domain_map, sizeof(nodemap)); |
| 2076 | spin_unlock(&dlm->spinlock); |
| 2077 | |
| 2078 | clear_bit(dlm->node_num, nodemap); |
| 2079 | if (ignore_higher) { |
| 2080 | /* if is this just to clear up mles for nodes below |
| 2081 | * this node, do not send the message to the original |
| 2082 | * caller or any node number higher than this */ |
| 2083 | clear_bit(request_from, nodemap); |
| 2084 | bit = dlm->node_num; |
| 2085 | while (1) { |
| 2086 | bit = find_next_bit(nodemap, O2NM_MAX_NODES, |
| 2087 | bit+1); |
| 2088 | if (bit >= O2NM_MAX_NODES) |
| 2089 | break; |
| 2090 | clear_bit(bit, nodemap); |
| 2091 | } |
| 2092 | } |
| 2093 | |
Kurt Hackel | 3640748 | 2006-05-01 13:32:27 -0700 | [diff] [blame] | 2094 | /* |
| 2095 | * If we're migrating this lock to someone else, we are no |
| 2096 | * longer allowed to assert out own mastery. OTOH, we need to |
| 2097 | * prevent migration from starting while we're still asserting |
| 2098 | * our dominance. The reserved ast delays migration. |
| 2099 | */ |
| 2100 | spin_lock(&res->spinlock); |
| 2101 | if (res->state & DLM_LOCK_RES_MIGRATING) { |
| 2102 | mlog(0, "Someone asked us to assert mastery, but we're " |
| 2103 | "in the middle of migration. Skipping assert, " |
| 2104 | "the new master will handle that.\n"); |
| 2105 | spin_unlock(&res->spinlock); |
| 2106 | goto put; |
| 2107 | } else |
| 2108 | __dlm_lockres_reserve_ast(res); |
| 2109 | spin_unlock(&res->spinlock); |
| 2110 | |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 2111 | /* this call now finishes out the nodemap |
| 2112 | * even if one or more nodes die */ |
| 2113 | mlog(0, "worker about to master %.*s here, this=%u\n", |
| 2114 | res->lockname.len, res->lockname.name, dlm->node_num); |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 2115 | ret = dlm_do_assert_master(dlm, res, nodemap, flags); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 2116 | if (ret < 0) { |
| 2117 | /* no need to restart, we are done */ |
Kurt Hackel | 3b3b84a | 2006-05-01 14:31:37 -0700 | [diff] [blame] | 2118 | if (!dlm_is_host_down(ret)) |
| 2119 | mlog_errno(ret); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 2120 | } |
| 2121 | |
Kurt Hackel | 3640748 | 2006-05-01 13:32:27 -0700 | [diff] [blame] | 2122 | /* Ok, we've asserted ourselves. Let's let migration start. */ |
| 2123 | dlm_lockres_release_ast(dlm, res); |
| 2124 | |
| 2125 | put: |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 2126 | dlm_lockres_put(res); |
| 2127 | |
| 2128 | mlog(0, "finished with dlm_assert_master_worker\n"); |
| 2129 | } |
| 2130 | |
Kurt Hackel | c03872f | 2006-03-06 14:08:49 -0800 | [diff] [blame] | 2131 | /* SPECIAL CASE for the $RECOVERY lock used by the recovery thread. |
| 2132 | * We cannot wait for node recovery to complete to begin mastering this |
| 2133 | * lockres because this lockres is used to kick off recovery! ;-) |
| 2134 | * So, do a pre-check on all living nodes to see if any of those nodes |
| 2135 | * think that $RECOVERY is currently mastered by a dead node. If so, |
| 2136 | * we wait a short time to allow that node to get notified by its own |
| 2137 | * heartbeat stack, then check again. All $RECOVERY lock resources |
| 2138 | * mastered by dead nodes are purged when the hearbeat callback is |
| 2139 | * fired, so we can know for sure that it is safe to continue once |
| 2140 | * the node returns a live node or no node. */ |
| 2141 | static int dlm_pre_master_reco_lockres(struct dlm_ctxt *dlm, |
| 2142 | struct dlm_lock_resource *res) |
| 2143 | { |
| 2144 | struct dlm_node_iter iter; |
| 2145 | int nodenum; |
| 2146 | int ret = 0; |
| 2147 | u8 master = DLM_LOCK_RES_OWNER_UNKNOWN; |
| 2148 | |
| 2149 | spin_lock(&dlm->spinlock); |
| 2150 | dlm_node_iter_init(dlm->domain_map, &iter); |
| 2151 | spin_unlock(&dlm->spinlock); |
| 2152 | |
| 2153 | while ((nodenum = dlm_node_iter_next(&iter)) >= 0) { |
| 2154 | /* do not send to self */ |
| 2155 | if (nodenum == dlm->node_num) |
| 2156 | continue; |
| 2157 | ret = dlm_do_master_requery(dlm, res, nodenum, &master); |
| 2158 | if (ret < 0) { |
| 2159 | mlog_errno(ret); |
| 2160 | if (!dlm_is_host_down(ret)) |
| 2161 | BUG(); |
| 2162 | /* host is down, so answer for that node would be |
| 2163 | * DLM_LOCK_RES_OWNER_UNKNOWN. continue. */ |
Kurt Hackel | f42a100 | 2006-05-01 11:53:33 -0700 | [diff] [blame] | 2164 | ret = 0; |
Kurt Hackel | c03872f | 2006-03-06 14:08:49 -0800 | [diff] [blame] | 2165 | } |
| 2166 | |
| 2167 | if (master != DLM_LOCK_RES_OWNER_UNKNOWN) { |
| 2168 | /* check to see if this master is in the recovery map */ |
| 2169 | spin_lock(&dlm->spinlock); |
| 2170 | if (test_bit(master, dlm->recovery_map)) { |
| 2171 | mlog(ML_NOTICE, "%s: node %u has not seen " |
| 2172 | "node %u go down yet, and thinks the " |
| 2173 | "dead node is mastering the recovery " |
| 2174 | "lock. must wait.\n", dlm->name, |
| 2175 | nodenum, master); |
| 2176 | ret = -EAGAIN; |
| 2177 | } |
| 2178 | spin_unlock(&dlm->spinlock); |
| 2179 | mlog(0, "%s: reco lock master is %u\n", dlm->name, |
| 2180 | master); |
| 2181 | break; |
| 2182 | } |
| 2183 | } |
| 2184 | return ret; |
| 2185 | } |
| 2186 | |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 2187 | /* |
| 2188 | * DLM_DEREF_LOCKRES_MSG |
| 2189 | */ |
| 2190 | |
| 2191 | int dlm_drop_lockres_ref(struct dlm_ctxt *dlm, struct dlm_lock_resource *res) |
| 2192 | { |
| 2193 | struct dlm_deref_lockres deref; |
| 2194 | int ret = 0, r; |
| 2195 | const char *lockname; |
| 2196 | unsigned int namelen; |
| 2197 | |
| 2198 | lockname = res->lockname.name; |
| 2199 | namelen = res->lockname.len; |
| 2200 | BUG_ON(namelen > O2NM_MAX_NAME_LEN); |
| 2201 | |
| 2202 | mlog(0, "%s:%.*s: sending deref to %d\n", |
| 2203 | dlm->name, namelen, lockname, res->owner); |
| 2204 | memset(&deref, 0, sizeof(deref)); |
| 2205 | deref.node_idx = dlm->node_num; |
| 2206 | deref.namelen = namelen; |
| 2207 | memcpy(deref.name, lockname, namelen); |
| 2208 | |
| 2209 | ret = o2net_send_message(DLM_DEREF_LOCKRES_MSG, dlm->key, |
| 2210 | &deref, sizeof(deref), res->owner, &r); |
| 2211 | if (ret < 0) |
| 2212 | mlog_errno(ret); |
| 2213 | else if (r < 0) { |
| 2214 | /* BAD. other node says I did not have a ref. */ |
| 2215 | mlog(ML_ERROR,"while dropping ref on %s:%.*s " |
| 2216 | "(master=%u) got %d.\n", dlm->name, namelen, |
| 2217 | lockname, res->owner, r); |
| 2218 | dlm_print_one_lock_resource(res); |
| 2219 | BUG(); |
| 2220 | } |
| 2221 | return ret; |
| 2222 | } |
| 2223 | |
Kurt Hackel | d74c980 | 2007-01-17 17:04:25 -0800 | [diff] [blame] | 2224 | int dlm_deref_lockres_handler(struct o2net_msg *msg, u32 len, void *data, |
| 2225 | void **ret_data) |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 2226 | { |
| 2227 | struct dlm_ctxt *dlm = data; |
| 2228 | struct dlm_deref_lockres *deref = (struct dlm_deref_lockres *)msg->buf; |
| 2229 | struct dlm_lock_resource *res = NULL; |
| 2230 | char *name; |
| 2231 | unsigned int namelen; |
| 2232 | int ret = -EINVAL; |
| 2233 | u8 node; |
| 2234 | unsigned int hash; |
Sunil Mushran | f3f8546 | 2007-01-29 15:19:16 -0800 | [diff] [blame] | 2235 | struct dlm_work_item *item; |
| 2236 | int cleared = 0; |
| 2237 | int dispatch = 0; |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 2238 | |
| 2239 | if (!dlm_grab(dlm)) |
| 2240 | return 0; |
| 2241 | |
| 2242 | name = deref->name; |
| 2243 | namelen = deref->namelen; |
| 2244 | node = deref->node_idx; |
| 2245 | |
| 2246 | if (namelen > DLM_LOCKID_NAME_MAX) { |
| 2247 | mlog(ML_ERROR, "Invalid name length!"); |
| 2248 | goto done; |
| 2249 | } |
| 2250 | if (deref->node_idx >= O2NM_MAX_NODES) { |
| 2251 | mlog(ML_ERROR, "Invalid node number: %u\n", node); |
| 2252 | goto done; |
| 2253 | } |
| 2254 | |
| 2255 | hash = dlm_lockid_hash(name, namelen); |
| 2256 | |
| 2257 | spin_lock(&dlm->spinlock); |
| 2258 | res = __dlm_lookup_lockres_full(dlm, name, namelen, hash); |
| 2259 | if (!res) { |
| 2260 | spin_unlock(&dlm->spinlock); |
| 2261 | mlog(ML_ERROR, "%s:%.*s: bad lockres name\n", |
| 2262 | dlm->name, namelen, name); |
| 2263 | goto done; |
| 2264 | } |
| 2265 | spin_unlock(&dlm->spinlock); |
| 2266 | |
| 2267 | spin_lock(&res->spinlock); |
Sunil Mushran | f3f8546 | 2007-01-29 15:19:16 -0800 | [diff] [blame] | 2268 | if (res->state & DLM_LOCK_RES_SETREF_INPROG) |
| 2269 | dispatch = 1; |
| 2270 | else { |
| 2271 | BUG_ON(res->state & DLM_LOCK_RES_DROPPING_REF); |
| 2272 | if (test_bit(node, res->refmap)) { |
| 2273 | dlm_lockres_clear_refmap_bit(node, res); |
| 2274 | cleared = 1; |
| 2275 | } |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 2276 | } |
| 2277 | spin_unlock(&res->spinlock); |
| 2278 | |
Sunil Mushran | f3f8546 | 2007-01-29 15:19:16 -0800 | [diff] [blame] | 2279 | if (!dispatch) { |
| 2280 | if (cleared) |
| 2281 | dlm_lockres_calc_usage(dlm, res); |
| 2282 | else { |
| 2283 | mlog(ML_ERROR, "%s:%.*s: node %u trying to drop ref " |
| 2284 | "but it is already dropped!\n", dlm->name, |
| 2285 | res->lockname.len, res->lockname.name, node); |
Tao Ma | 2af37ce | 2008-02-28 10:41:55 +0800 | [diff] [blame] | 2286 | dlm_print_one_lock_resource(res); |
Sunil Mushran | f3f8546 | 2007-01-29 15:19:16 -0800 | [diff] [blame] | 2287 | } |
| 2288 | ret = 0; |
| 2289 | goto done; |
| 2290 | } |
| 2291 | |
| 2292 | item = kzalloc(sizeof(*item), GFP_NOFS); |
| 2293 | if (!item) { |
| 2294 | ret = -ENOMEM; |
| 2295 | mlog_errno(ret); |
| 2296 | goto done; |
| 2297 | } |
| 2298 | |
| 2299 | dlm_init_work_item(dlm, item, dlm_deref_lockres_worker, NULL); |
| 2300 | item->u.dl.deref_res = res; |
| 2301 | item->u.dl.deref_node = node; |
| 2302 | |
| 2303 | spin_lock(&dlm->work_lock); |
| 2304 | list_add_tail(&item->list, &dlm->work_list); |
| 2305 | spin_unlock(&dlm->work_lock); |
| 2306 | |
| 2307 | queue_work(dlm->dlm_worker, &dlm->dispatched_work); |
| 2308 | return 0; |
| 2309 | |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 2310 | done: |
| 2311 | if (res) |
| 2312 | dlm_lockres_put(res); |
| 2313 | dlm_put(dlm); |
Sunil Mushran | f3f8546 | 2007-01-29 15:19:16 -0800 | [diff] [blame] | 2314 | |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 2315 | return ret; |
| 2316 | } |
| 2317 | |
Sunil Mushran | f3f8546 | 2007-01-29 15:19:16 -0800 | [diff] [blame] | 2318 | static void dlm_deref_lockres_worker(struct dlm_work_item *item, void *data) |
| 2319 | { |
| 2320 | struct dlm_ctxt *dlm; |
| 2321 | struct dlm_lock_resource *res; |
| 2322 | u8 node; |
| 2323 | u8 cleared = 0; |
| 2324 | |
| 2325 | dlm = item->dlm; |
| 2326 | res = item->u.dl.deref_res; |
| 2327 | node = item->u.dl.deref_node; |
| 2328 | |
| 2329 | spin_lock(&res->spinlock); |
| 2330 | BUG_ON(res->state & DLM_LOCK_RES_DROPPING_REF); |
| 2331 | if (test_bit(node, res->refmap)) { |
| 2332 | __dlm_wait_on_lockres_flags(res, DLM_LOCK_RES_SETREF_INPROG); |
| 2333 | dlm_lockres_clear_refmap_bit(node, res); |
| 2334 | cleared = 1; |
| 2335 | } |
| 2336 | spin_unlock(&res->spinlock); |
| 2337 | |
| 2338 | if (cleared) { |
| 2339 | mlog(0, "%s:%.*s node %u ref dropped in dispatch\n", |
| 2340 | dlm->name, res->lockname.len, res->lockname.name, node); |
| 2341 | dlm_lockres_calc_usage(dlm, res); |
| 2342 | } else { |
| 2343 | mlog(ML_ERROR, "%s:%.*s: node %u trying to drop ref " |
| 2344 | "but it is already dropped!\n", dlm->name, |
| 2345 | res->lockname.len, res->lockname.name, node); |
Tao Ma | 2af37ce | 2008-02-28 10:41:55 +0800 | [diff] [blame] | 2346 | dlm_print_one_lock_resource(res); |
Sunil Mushran | f3f8546 | 2007-01-29 15:19:16 -0800 | [diff] [blame] | 2347 | } |
| 2348 | |
| 2349 | dlm_lockres_put(res); |
| 2350 | } |
| 2351 | |
Sunil Mushran | 2f5bf1f | 2007-03-22 17:08:32 -0700 | [diff] [blame] | 2352 | /* Checks whether the lockres can be migrated. Returns 0 if yes, < 0 |
| 2353 | * if not. If 0, numlocks is set to the number of locks in the lockres. |
| 2354 | */ |
| 2355 | static int dlm_is_lockres_migrateable(struct dlm_ctxt *dlm, |
| 2356 | struct dlm_lock_resource *res, |
| 2357 | int *numlocks) |
| 2358 | { |
| 2359 | int ret; |
| 2360 | int i; |
| 2361 | int count = 0; |
Christoph Hellwig | 800deef | 2007-05-17 16:03:13 +0200 | [diff] [blame] | 2362 | struct list_head *queue; |
Sunil Mushran | 2f5bf1f | 2007-03-22 17:08:32 -0700 | [diff] [blame] | 2363 | struct dlm_lock *lock; |
| 2364 | |
| 2365 | assert_spin_locked(&res->spinlock); |
| 2366 | |
| 2367 | ret = -EINVAL; |
| 2368 | if (res->owner == DLM_LOCK_RES_OWNER_UNKNOWN) { |
| 2369 | mlog(0, "cannot migrate lockres with unknown owner!\n"); |
| 2370 | goto leave; |
| 2371 | } |
| 2372 | |
| 2373 | if (res->owner != dlm->node_num) { |
| 2374 | mlog(0, "cannot migrate lockres this node doesn't own!\n"); |
| 2375 | goto leave; |
| 2376 | } |
| 2377 | |
| 2378 | ret = 0; |
| 2379 | queue = &res->granted; |
| 2380 | for (i = 0; i < 3; i++) { |
Christoph Hellwig | 800deef | 2007-05-17 16:03:13 +0200 | [diff] [blame] | 2381 | list_for_each_entry(lock, queue, list) { |
Sunil Mushran | 2f5bf1f | 2007-03-22 17:08:32 -0700 | [diff] [blame] | 2382 | ++count; |
| 2383 | if (lock->ml.node == dlm->node_num) { |
| 2384 | mlog(0, "found a lock owned by this node still " |
| 2385 | "on the %s queue! will not migrate this " |
| 2386 | "lockres\n", (i == 0 ? "granted" : |
| 2387 | (i == 1 ? "converting" : |
| 2388 | "blocked"))); |
| 2389 | ret = -ENOTEMPTY; |
| 2390 | goto leave; |
| 2391 | } |
| 2392 | } |
| 2393 | queue++; |
| 2394 | } |
| 2395 | |
| 2396 | *numlocks = count; |
| 2397 | mlog(0, "migrateable lockres having %d locks\n", *numlocks); |
| 2398 | |
| 2399 | leave: |
| 2400 | return ret; |
| 2401 | } |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 2402 | |
| 2403 | /* |
| 2404 | * DLM_MIGRATE_LOCKRES |
| 2405 | */ |
| 2406 | |
| 2407 | |
Adrian Bunk | faf0ec9 | 2006-12-14 00:17:32 +0100 | [diff] [blame] | 2408 | static int dlm_migrate_lockres(struct dlm_ctxt *dlm, |
| 2409 | struct dlm_lock_resource *res, |
| 2410 | u8 target) |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 2411 | { |
| 2412 | struct dlm_master_list_entry *mle = NULL; |
| 2413 | struct dlm_master_list_entry *oldmle = NULL; |
| 2414 | struct dlm_migratable_lockres *mres = NULL; |
Sunil Mushran | 2f5bf1f | 2007-03-22 17:08:32 -0700 | [diff] [blame] | 2415 | int ret = 0; |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 2416 | const char *name; |
| 2417 | unsigned int namelen; |
| 2418 | int mle_added = 0; |
Sunil Mushran | 2f5bf1f | 2007-03-22 17:08:32 -0700 | [diff] [blame] | 2419 | int numlocks; |
| 2420 | int wake = 0; |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 2421 | |
| 2422 | if (!dlm_grab(dlm)) |
| 2423 | return -EINVAL; |
| 2424 | |
| 2425 | name = res->lockname.name; |
| 2426 | namelen = res->lockname.len; |
| 2427 | |
| 2428 | mlog(0, "migrating %.*s to %u\n", namelen, name, target); |
| 2429 | |
| 2430 | /* |
| 2431 | * ensure this lockres is a proper candidate for migration |
| 2432 | */ |
| 2433 | spin_lock(&res->spinlock); |
Sunil Mushran | 2f5bf1f | 2007-03-22 17:08:32 -0700 | [diff] [blame] | 2434 | ret = dlm_is_lockres_migrateable(dlm, res, &numlocks); |
| 2435 | if (ret < 0) { |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 2436 | spin_unlock(&res->spinlock); |
| 2437 | goto leave; |
| 2438 | } |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 2439 | spin_unlock(&res->spinlock); |
| 2440 | |
| 2441 | /* no work to do */ |
Sunil Mushran | 2f5bf1f | 2007-03-22 17:08:32 -0700 | [diff] [blame] | 2442 | if (numlocks == 0) { |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 2443 | mlog(0, "no locks were found on this lockres! done!\n"); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 2444 | goto leave; |
| 2445 | } |
| 2446 | |
| 2447 | /* |
| 2448 | * preallocate up front |
| 2449 | * if this fails, abort |
| 2450 | */ |
| 2451 | |
| 2452 | ret = -ENOMEM; |
Kurt Hackel | ad8100e | 2006-05-01 14:25:21 -0700 | [diff] [blame] | 2453 | mres = (struct dlm_migratable_lockres *) __get_free_page(GFP_NOFS); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 2454 | if (!mres) { |
| 2455 | mlog_errno(ret); |
| 2456 | goto leave; |
| 2457 | } |
| 2458 | |
| 2459 | mle = (struct dlm_master_list_entry *) kmem_cache_alloc(dlm_mle_cache, |
Kurt Hackel | ad8100e | 2006-05-01 14:25:21 -0700 | [diff] [blame] | 2460 | GFP_NOFS); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 2461 | if (!mle) { |
| 2462 | mlog_errno(ret); |
| 2463 | goto leave; |
| 2464 | } |
| 2465 | ret = 0; |
| 2466 | |
| 2467 | /* |
| 2468 | * find a node to migrate the lockres to |
| 2469 | */ |
| 2470 | |
| 2471 | mlog(0, "picking a migration node\n"); |
| 2472 | spin_lock(&dlm->spinlock); |
| 2473 | /* pick a new node */ |
| 2474 | if (!test_bit(target, dlm->domain_map) || |
| 2475 | target >= O2NM_MAX_NODES) { |
| 2476 | target = dlm_pick_migration_target(dlm, res); |
| 2477 | } |
| 2478 | mlog(0, "node %u chosen for migration\n", target); |
| 2479 | |
| 2480 | if (target >= O2NM_MAX_NODES || |
| 2481 | !test_bit(target, dlm->domain_map)) { |
| 2482 | /* target chosen is not alive */ |
| 2483 | ret = -EINVAL; |
| 2484 | } |
| 2485 | |
| 2486 | if (ret) { |
| 2487 | spin_unlock(&dlm->spinlock); |
| 2488 | goto fail; |
| 2489 | } |
| 2490 | |
| 2491 | mlog(0, "continuing with target = %u\n", target); |
| 2492 | |
| 2493 | /* |
| 2494 | * clear any existing master requests and |
| 2495 | * add the migration mle to the list |
| 2496 | */ |
| 2497 | spin_lock(&dlm->master_lock); |
| 2498 | ret = dlm_add_migration_mle(dlm, res, mle, &oldmle, name, |
| 2499 | namelen, target, dlm->node_num); |
| 2500 | spin_unlock(&dlm->master_lock); |
| 2501 | spin_unlock(&dlm->spinlock); |
| 2502 | |
| 2503 | if (ret == -EEXIST) { |
| 2504 | mlog(0, "another process is already migrating it\n"); |
| 2505 | goto fail; |
| 2506 | } |
| 2507 | mle_added = 1; |
| 2508 | |
| 2509 | /* |
| 2510 | * set the MIGRATING flag and flush asts |
| 2511 | * if we fail after this we need to re-dirty the lockres |
| 2512 | */ |
| 2513 | if (dlm_mark_lockres_migrating(dlm, res, target) < 0) { |
| 2514 | mlog(ML_ERROR, "tried to migrate %.*s to %u, but " |
| 2515 | "the target went down.\n", res->lockname.len, |
| 2516 | res->lockname.name, target); |
| 2517 | spin_lock(&res->spinlock); |
| 2518 | res->state &= ~DLM_LOCK_RES_MIGRATING; |
Kurt Hackel | a6fa364 | 2007-01-17 14:59:12 -0800 | [diff] [blame] | 2519 | wake = 1; |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 2520 | spin_unlock(&res->spinlock); |
| 2521 | ret = -EINVAL; |
| 2522 | } |
| 2523 | |
| 2524 | fail: |
| 2525 | if (oldmle) { |
| 2526 | /* master is known, detach if not already detached */ |
| 2527 | dlm_mle_detach_hb_events(dlm, oldmle); |
| 2528 | dlm_put_mle(oldmle); |
| 2529 | } |
| 2530 | |
| 2531 | if (ret < 0) { |
| 2532 | if (mle_added) { |
| 2533 | dlm_mle_detach_hb_events(dlm, mle); |
| 2534 | dlm_put_mle(mle); |
| 2535 | } else if (mle) { |
| 2536 | kmem_cache_free(dlm_mle_cache, mle); |
| 2537 | } |
| 2538 | goto leave; |
| 2539 | } |
| 2540 | |
| 2541 | /* |
| 2542 | * at this point, we have a migration target, an mle |
| 2543 | * in the master list, and the MIGRATING flag set on |
| 2544 | * the lockres |
| 2545 | */ |
| 2546 | |
Kurt Hackel | 1cd04db | 2007-01-17 14:53:37 -0800 | [diff] [blame] | 2547 | /* now that remote nodes are spinning on the MIGRATING flag, |
| 2548 | * ensure that all assert_master work is flushed. */ |
| 2549 | flush_workqueue(dlm->dlm_worker); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 2550 | |
| 2551 | /* get an extra reference on the mle. |
| 2552 | * otherwise the assert_master from the new |
| 2553 | * master will destroy this. |
| 2554 | * also, make sure that all callers of dlm_get_mle |
| 2555 | * take both dlm->spinlock and dlm->master_lock */ |
| 2556 | spin_lock(&dlm->spinlock); |
| 2557 | spin_lock(&dlm->master_lock); |
Kurt Hackel | a2bf047 | 2006-04-27 18:51:26 -0700 | [diff] [blame] | 2558 | dlm_get_mle_inuse(mle); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 2559 | spin_unlock(&dlm->master_lock); |
| 2560 | spin_unlock(&dlm->spinlock); |
| 2561 | |
| 2562 | /* notify new node and send all lock state */ |
| 2563 | /* call send_one_lockres with migration flag. |
| 2564 | * this serves as notice to the target node that a |
| 2565 | * migration is starting. */ |
| 2566 | ret = dlm_send_one_lockres(dlm, res, mres, target, |
| 2567 | DLM_MRES_MIGRATION); |
| 2568 | |
| 2569 | if (ret < 0) { |
| 2570 | mlog(0, "migration to node %u failed with %d\n", |
| 2571 | target, ret); |
| 2572 | /* migration failed, detach and clean up mle */ |
| 2573 | dlm_mle_detach_hb_events(dlm, mle); |
| 2574 | dlm_put_mle(mle); |
Kurt Hackel | a2bf047 | 2006-04-27 18:51:26 -0700 | [diff] [blame] | 2575 | dlm_put_mle_inuse(mle); |
| 2576 | spin_lock(&res->spinlock); |
| 2577 | res->state &= ~DLM_LOCK_RES_MIGRATING; |
Kurt Hackel | a6fa364 | 2007-01-17 14:59:12 -0800 | [diff] [blame] | 2578 | wake = 1; |
Kurt Hackel | a2bf047 | 2006-04-27 18:51:26 -0700 | [diff] [blame] | 2579 | spin_unlock(&res->spinlock); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 2580 | goto leave; |
| 2581 | } |
| 2582 | |
| 2583 | /* at this point, the target sends a message to all nodes, |
| 2584 | * (using dlm_do_migrate_request). this node is skipped since |
| 2585 | * we had to put an mle in the list to begin the process. this |
| 2586 | * node now waits for target to do an assert master. this node |
| 2587 | * will be the last one notified, ensuring that the migration |
| 2588 | * is complete everywhere. if the target dies while this is |
| 2589 | * going on, some nodes could potentially see the target as the |
| 2590 | * master, so it is important that my recovery finds the migration |
| 2591 | * mle and sets the master to UNKNONWN. */ |
| 2592 | |
| 2593 | |
| 2594 | /* wait for new node to assert master */ |
| 2595 | while (1) { |
| 2596 | ret = wait_event_interruptible_timeout(mle->wq, |
| 2597 | (atomic_read(&mle->woken) == 1), |
| 2598 | msecs_to_jiffies(5000)); |
| 2599 | |
| 2600 | if (ret >= 0) { |
| 2601 | if (atomic_read(&mle->woken) == 1 || |
| 2602 | res->owner == target) |
| 2603 | break; |
| 2604 | |
Kurt Hackel | 1cd04db | 2007-01-17 14:53:37 -0800 | [diff] [blame] | 2605 | mlog(0, "%s:%.*s: timed out during migration\n", |
| 2606 | dlm->name, res->lockname.len, res->lockname.name); |
Kurt Hackel | e2faea4 | 2006-01-12 14:24:55 -0800 | [diff] [blame] | 2607 | /* avoid hang during shutdown when migrating lockres |
| 2608 | * to a node which also goes down */ |
| 2609 | if (dlm_is_node_dead(dlm, target)) { |
Kurt Hackel | aa85235 | 2006-04-27 19:04:49 -0700 | [diff] [blame] | 2610 | mlog(0, "%s:%.*s: expected migration " |
| 2611 | "target %u is no longer up, restarting\n", |
Kurt Hackel | e2faea4 | 2006-01-12 14:24:55 -0800 | [diff] [blame] | 2612 | dlm->name, res->lockname.len, |
| 2613 | res->lockname.name, target); |
Kurt Hackel | 1cd04db | 2007-01-17 14:53:37 -0800 | [diff] [blame] | 2614 | ret = -EINVAL; |
| 2615 | /* migration failed, detach and clean up mle */ |
| 2616 | dlm_mle_detach_hb_events(dlm, mle); |
| 2617 | dlm_put_mle(mle); |
| 2618 | dlm_put_mle_inuse(mle); |
| 2619 | spin_lock(&res->spinlock); |
| 2620 | res->state &= ~DLM_LOCK_RES_MIGRATING; |
Kurt Hackel | a6fa364 | 2007-01-17 14:59:12 -0800 | [diff] [blame] | 2621 | wake = 1; |
Kurt Hackel | 1cd04db | 2007-01-17 14:53:37 -0800 | [diff] [blame] | 2622 | spin_unlock(&res->spinlock); |
| 2623 | goto leave; |
Kurt Hackel | e2faea4 | 2006-01-12 14:24:55 -0800 | [diff] [blame] | 2624 | } |
Kurt Hackel | 1cd04db | 2007-01-17 14:53:37 -0800 | [diff] [blame] | 2625 | } else |
| 2626 | mlog(0, "%s:%.*s: caught signal during migration\n", |
| 2627 | dlm->name, res->lockname.len, res->lockname.name); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 2628 | } |
| 2629 | |
| 2630 | /* all done, set the owner, clear the flag */ |
| 2631 | spin_lock(&res->spinlock); |
| 2632 | dlm_set_lockres_owner(dlm, res, target); |
| 2633 | res->state &= ~DLM_LOCK_RES_MIGRATING; |
| 2634 | dlm_remove_nonlocal_locks(dlm, res); |
| 2635 | spin_unlock(&res->spinlock); |
| 2636 | wake_up(&res->wq); |
| 2637 | |
| 2638 | /* master is known, detach if not already detached */ |
| 2639 | dlm_mle_detach_hb_events(dlm, mle); |
Kurt Hackel | a2bf047 | 2006-04-27 18:51:26 -0700 | [diff] [blame] | 2640 | dlm_put_mle_inuse(mle); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 2641 | ret = 0; |
| 2642 | |
| 2643 | dlm_lockres_calc_usage(dlm, res); |
| 2644 | |
| 2645 | leave: |
| 2646 | /* re-dirty the lockres if we failed */ |
| 2647 | if (ret < 0) |
| 2648 | dlm_kick_thread(dlm, res); |
| 2649 | |
Kurt Hackel | a6fa364 | 2007-01-17 14:59:12 -0800 | [diff] [blame] | 2650 | /* wake up waiters if the MIGRATING flag got set |
| 2651 | * but migration failed */ |
| 2652 | if (wake) |
| 2653 | wake_up(&res->wq); |
| 2654 | |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 2655 | /* TODO: cleanup */ |
| 2656 | if (mres) |
| 2657 | free_page((unsigned long)mres); |
| 2658 | |
| 2659 | dlm_put(dlm); |
| 2660 | |
| 2661 | mlog(0, "returning %d\n", ret); |
| 2662 | return ret; |
| 2663 | } |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 2664 | |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 2665 | #define DLM_MIGRATION_RETRY_MS 100 |
| 2666 | |
| 2667 | /* Should be called only after beginning the domain leave process. |
| 2668 | * There should not be any remaining locks on nonlocal lock resources, |
| 2669 | * and there should be no local locks left on locally mastered resources. |
| 2670 | * |
| 2671 | * Called with the dlm spinlock held, may drop it to do migration, but |
| 2672 | * will re-acquire before exit. |
| 2673 | * |
| 2674 | * Returns: 1 if dlm->spinlock was dropped/retaken, 0 if never dropped */ |
| 2675 | int dlm_empty_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res) |
| 2676 | { |
| 2677 | int ret; |
| 2678 | int lock_dropped = 0; |
Sunil Mushran | 2f5bf1f | 2007-03-22 17:08:32 -0700 | [diff] [blame] | 2679 | int numlocks; |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 2680 | |
Sunil Mushran | b36c3f8 | 2007-03-12 13:25:44 -0700 | [diff] [blame] | 2681 | spin_lock(&res->spinlock); |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 2682 | if (res->owner != dlm->node_num) { |
| 2683 | if (!__dlm_lockres_unused(res)) { |
| 2684 | mlog(ML_ERROR, "%s:%.*s: this node is not master, " |
| 2685 | "trying to free this but locks remain\n", |
| 2686 | dlm->name, res->lockname.len, res->lockname.name); |
| 2687 | } |
Sunil Mushran | b36c3f8 | 2007-03-12 13:25:44 -0700 | [diff] [blame] | 2688 | spin_unlock(&res->spinlock); |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 2689 | goto leave; |
| 2690 | } |
Sunil Mushran | 2f5bf1f | 2007-03-22 17:08:32 -0700 | [diff] [blame] | 2691 | |
| 2692 | /* No need to migrate a lockres having no locks */ |
| 2693 | ret = dlm_is_lockres_migrateable(dlm, res, &numlocks); |
| 2694 | if (ret >= 0 && numlocks == 0) { |
| 2695 | spin_unlock(&res->spinlock); |
| 2696 | goto leave; |
| 2697 | } |
Sunil Mushran | b36c3f8 | 2007-03-12 13:25:44 -0700 | [diff] [blame] | 2698 | spin_unlock(&res->spinlock); |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 2699 | |
| 2700 | /* Wheee! Migrate lockres here! Will sleep so drop spinlock. */ |
| 2701 | spin_unlock(&dlm->spinlock); |
| 2702 | lock_dropped = 1; |
| 2703 | while (1) { |
| 2704 | ret = dlm_migrate_lockres(dlm, res, O2NM_MAX_NODES); |
| 2705 | if (ret >= 0) |
| 2706 | break; |
| 2707 | if (ret == -ENOTEMPTY) { |
| 2708 | mlog(ML_ERROR, "lockres %.*s still has local locks!\n", |
| 2709 | res->lockname.len, res->lockname.name); |
| 2710 | BUG(); |
| 2711 | } |
| 2712 | |
| 2713 | mlog(0, "lockres %.*s: migrate failed, " |
| 2714 | "retrying\n", res->lockname.len, |
| 2715 | res->lockname.name); |
| 2716 | msleep(DLM_MIGRATION_RETRY_MS); |
| 2717 | } |
| 2718 | spin_lock(&dlm->spinlock); |
| 2719 | leave: |
| 2720 | return lock_dropped; |
| 2721 | } |
| 2722 | |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 2723 | int dlm_lock_basts_flushed(struct dlm_ctxt *dlm, struct dlm_lock *lock) |
| 2724 | { |
| 2725 | int ret; |
| 2726 | spin_lock(&dlm->ast_lock); |
| 2727 | spin_lock(&lock->spinlock); |
| 2728 | ret = (list_empty(&lock->bast_list) && !lock->bast_pending); |
| 2729 | spin_unlock(&lock->spinlock); |
| 2730 | spin_unlock(&dlm->ast_lock); |
| 2731 | return ret; |
| 2732 | } |
| 2733 | |
| 2734 | static int dlm_migration_can_proceed(struct dlm_ctxt *dlm, |
| 2735 | struct dlm_lock_resource *res, |
| 2736 | u8 mig_target) |
| 2737 | { |
| 2738 | int can_proceed; |
| 2739 | spin_lock(&res->spinlock); |
| 2740 | can_proceed = !!(res->state & DLM_LOCK_RES_MIGRATING); |
| 2741 | spin_unlock(&res->spinlock); |
| 2742 | |
| 2743 | /* target has died, so make the caller break out of the |
| 2744 | * wait_event, but caller must recheck the domain_map */ |
| 2745 | spin_lock(&dlm->spinlock); |
| 2746 | if (!test_bit(mig_target, dlm->domain_map)) |
| 2747 | can_proceed = 1; |
| 2748 | spin_unlock(&dlm->spinlock); |
| 2749 | return can_proceed; |
| 2750 | } |
| 2751 | |
Adrian Bunk | faf0ec9 | 2006-12-14 00:17:32 +0100 | [diff] [blame] | 2752 | static int dlm_lockres_is_dirty(struct dlm_ctxt *dlm, |
| 2753 | struct dlm_lock_resource *res) |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 2754 | { |
| 2755 | int ret; |
| 2756 | spin_lock(&res->spinlock); |
| 2757 | ret = !!(res->state & DLM_LOCK_RES_DIRTY); |
| 2758 | spin_unlock(&res->spinlock); |
| 2759 | return ret; |
| 2760 | } |
| 2761 | |
| 2762 | |
| 2763 | static int dlm_mark_lockres_migrating(struct dlm_ctxt *dlm, |
| 2764 | struct dlm_lock_resource *res, |
| 2765 | u8 target) |
| 2766 | { |
| 2767 | int ret = 0; |
| 2768 | |
| 2769 | mlog(0, "dlm_mark_lockres_migrating: %.*s, from %u to %u\n", |
| 2770 | res->lockname.len, res->lockname.name, dlm->node_num, |
| 2771 | target); |
| 2772 | /* need to set MIGRATING flag on lockres. this is done by |
| 2773 | * ensuring that all asts have been flushed for this lockres. */ |
| 2774 | spin_lock(&res->spinlock); |
| 2775 | BUG_ON(res->migration_pending); |
| 2776 | res->migration_pending = 1; |
| 2777 | /* strategy is to reserve an extra ast then release |
| 2778 | * it below, letting the release do all of the work */ |
| 2779 | __dlm_lockres_reserve_ast(res); |
| 2780 | spin_unlock(&res->spinlock); |
| 2781 | |
Kurt Hackel | ddc09c8 | 2007-01-05 15:00:17 -0800 | [diff] [blame] | 2782 | /* now flush all the pending asts */ |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 2783 | dlm_kick_thread(dlm, res); |
Kurt Hackel | ddc09c8 | 2007-01-05 15:00:17 -0800 | [diff] [blame] | 2784 | /* before waiting on DIRTY, block processes which may |
| 2785 | * try to dirty the lockres before MIGRATING is set */ |
| 2786 | spin_lock(&res->spinlock); |
| 2787 | BUG_ON(res->state & DLM_LOCK_RES_BLOCK_DIRTY); |
| 2788 | res->state |= DLM_LOCK_RES_BLOCK_DIRTY; |
| 2789 | spin_unlock(&res->spinlock); |
| 2790 | /* now wait on any pending asts and the DIRTY state */ |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 2791 | wait_event(dlm->ast_wq, !dlm_lockres_is_dirty(dlm, res)); |
| 2792 | dlm_lockres_release_ast(dlm, res); |
| 2793 | |
| 2794 | mlog(0, "about to wait on migration_wq, dirty=%s\n", |
| 2795 | res->state & DLM_LOCK_RES_DIRTY ? "yes" : "no"); |
| 2796 | /* if the extra ref we just put was the final one, this |
| 2797 | * will pass thru immediately. otherwise, we need to wait |
| 2798 | * for the last ast to finish. */ |
| 2799 | again: |
| 2800 | ret = wait_event_interruptible_timeout(dlm->migration_wq, |
| 2801 | dlm_migration_can_proceed(dlm, res, target), |
| 2802 | msecs_to_jiffies(1000)); |
| 2803 | if (ret < 0) { |
| 2804 | mlog(0, "woken again: migrating? %s, dead? %s\n", |
| 2805 | res->state & DLM_LOCK_RES_MIGRATING ? "yes":"no", |
| 2806 | test_bit(target, dlm->domain_map) ? "no":"yes"); |
| 2807 | } else { |
| 2808 | mlog(0, "all is well: migrating? %s, dead? %s\n", |
| 2809 | res->state & DLM_LOCK_RES_MIGRATING ? "yes":"no", |
| 2810 | test_bit(target, dlm->domain_map) ? "no":"yes"); |
| 2811 | } |
| 2812 | if (!dlm_migration_can_proceed(dlm, res, target)) { |
| 2813 | mlog(0, "trying again...\n"); |
| 2814 | goto again; |
| 2815 | } |
Kurt Hackel | ddc09c8 | 2007-01-05 15:00:17 -0800 | [diff] [blame] | 2816 | /* now that we are sure the MIGRATING state is there, drop |
| 2817 | * the unneded state which blocked threads trying to DIRTY */ |
| 2818 | spin_lock(&res->spinlock); |
| 2819 | BUG_ON(!(res->state & DLM_LOCK_RES_BLOCK_DIRTY)); |
| 2820 | BUG_ON(!(res->state & DLM_LOCK_RES_MIGRATING)); |
| 2821 | res->state &= ~DLM_LOCK_RES_BLOCK_DIRTY; |
| 2822 | spin_unlock(&res->spinlock); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 2823 | |
| 2824 | /* did the target go down or die? */ |
| 2825 | spin_lock(&dlm->spinlock); |
| 2826 | if (!test_bit(target, dlm->domain_map)) { |
| 2827 | mlog(ML_ERROR, "aha. migration target %u just went down\n", |
| 2828 | target); |
| 2829 | ret = -EHOSTDOWN; |
| 2830 | } |
| 2831 | spin_unlock(&dlm->spinlock); |
| 2832 | |
| 2833 | /* |
| 2834 | * at this point: |
| 2835 | * |
| 2836 | * o the DLM_LOCK_RES_MIGRATING flag is set |
| 2837 | * o there are no pending asts on this lockres |
| 2838 | * o all processes trying to reserve an ast on this |
| 2839 | * lockres must wait for the MIGRATING flag to clear |
| 2840 | */ |
| 2841 | return ret; |
| 2842 | } |
| 2843 | |
| 2844 | /* last step in the migration process. |
| 2845 | * original master calls this to free all of the dlm_lock |
| 2846 | * structures that used to be for other nodes. */ |
| 2847 | static void dlm_remove_nonlocal_locks(struct dlm_ctxt *dlm, |
| 2848 | struct dlm_lock_resource *res) |
| 2849 | { |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 2850 | struct list_head *queue = &res->granted; |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 2851 | int i, bit; |
Christoph Hellwig | 800deef | 2007-05-17 16:03:13 +0200 | [diff] [blame] | 2852 | struct dlm_lock *lock, *next; |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 2853 | |
| 2854 | assert_spin_locked(&res->spinlock); |
| 2855 | |
| 2856 | BUG_ON(res->owner == dlm->node_num); |
| 2857 | |
| 2858 | for (i=0; i<3; i++) { |
Christoph Hellwig | 800deef | 2007-05-17 16:03:13 +0200 | [diff] [blame] | 2859 | list_for_each_entry_safe(lock, next, queue, list) { |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 2860 | if (lock->ml.node != dlm->node_num) { |
| 2861 | mlog(0, "putting lock for node %u\n", |
| 2862 | lock->ml.node); |
| 2863 | /* be extra careful */ |
| 2864 | BUG_ON(!list_empty(&lock->ast_list)); |
| 2865 | BUG_ON(!list_empty(&lock->bast_list)); |
| 2866 | BUG_ON(lock->ast_pending); |
| 2867 | BUG_ON(lock->bast_pending); |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 2868 | dlm_lockres_clear_refmap_bit(lock->ml.node, res); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 2869 | list_del_init(&lock->list); |
| 2870 | dlm_lock_put(lock); |
Sunil Mushran | 2c5c54a | 2008-03-01 14:04:20 -0800 | [diff] [blame] | 2871 | /* In a normal unlock, we would have added a |
| 2872 | * DLM_UNLOCK_FREE_LOCK action. Force it. */ |
| 2873 | dlm_lock_put(lock); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 2874 | } |
| 2875 | } |
| 2876 | queue++; |
| 2877 | } |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 2878 | bit = 0; |
| 2879 | while (1) { |
| 2880 | bit = find_next_bit(res->refmap, O2NM_MAX_NODES, bit); |
| 2881 | if (bit >= O2NM_MAX_NODES) |
| 2882 | break; |
| 2883 | /* do not clear the local node reference, if there is a |
| 2884 | * process holding this, let it drop the ref itself */ |
| 2885 | if (bit != dlm->node_num) { |
| 2886 | mlog(0, "%s:%.*s: node %u had a ref to this " |
| 2887 | "migrating lockres, clearing\n", dlm->name, |
| 2888 | res->lockname.len, res->lockname.name, bit); |
| 2889 | dlm_lockres_clear_refmap_bit(bit, res); |
| 2890 | } |
| 2891 | bit++; |
| 2892 | } |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 2893 | } |
| 2894 | |
| 2895 | /* for now this is not too intelligent. we will |
| 2896 | * need stats to make this do the right thing. |
| 2897 | * this just finds the first lock on one of the |
| 2898 | * queues and uses that node as the target. */ |
| 2899 | static u8 dlm_pick_migration_target(struct dlm_ctxt *dlm, |
| 2900 | struct dlm_lock_resource *res) |
| 2901 | { |
| 2902 | int i; |
| 2903 | struct list_head *queue = &res->granted; |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 2904 | struct dlm_lock *lock; |
| 2905 | int nodenum; |
| 2906 | |
| 2907 | assert_spin_locked(&dlm->spinlock); |
| 2908 | |
| 2909 | spin_lock(&res->spinlock); |
| 2910 | for (i=0; i<3; i++) { |
Christoph Hellwig | 800deef | 2007-05-17 16:03:13 +0200 | [diff] [blame] | 2911 | list_for_each_entry(lock, queue, list) { |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 2912 | /* up to the caller to make sure this node |
| 2913 | * is alive */ |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 2914 | if (lock->ml.node != dlm->node_num) { |
| 2915 | spin_unlock(&res->spinlock); |
| 2916 | return lock->ml.node; |
| 2917 | } |
| 2918 | } |
| 2919 | queue++; |
| 2920 | } |
| 2921 | spin_unlock(&res->spinlock); |
| 2922 | mlog(0, "have not found a suitable target yet! checking domain map\n"); |
| 2923 | |
| 2924 | /* ok now we're getting desperate. pick anyone alive. */ |
| 2925 | nodenum = -1; |
| 2926 | while (1) { |
| 2927 | nodenum = find_next_bit(dlm->domain_map, |
| 2928 | O2NM_MAX_NODES, nodenum+1); |
| 2929 | mlog(0, "found %d in domain map\n", nodenum); |
| 2930 | if (nodenum >= O2NM_MAX_NODES) |
| 2931 | break; |
| 2932 | if (nodenum != dlm->node_num) { |
| 2933 | mlog(0, "picking %d\n", nodenum); |
| 2934 | return nodenum; |
| 2935 | } |
| 2936 | } |
| 2937 | |
| 2938 | mlog(0, "giving up. no master to migrate to\n"); |
| 2939 | return DLM_LOCK_RES_OWNER_UNKNOWN; |
| 2940 | } |
| 2941 | |
| 2942 | |
| 2943 | |
| 2944 | /* this is called by the new master once all lockres |
| 2945 | * data has been received */ |
| 2946 | static int dlm_do_migrate_request(struct dlm_ctxt *dlm, |
| 2947 | struct dlm_lock_resource *res, |
| 2948 | u8 master, u8 new_master, |
| 2949 | struct dlm_node_iter *iter) |
| 2950 | { |
| 2951 | struct dlm_migrate_request migrate; |
| 2952 | int ret, status = 0; |
| 2953 | int nodenum; |
| 2954 | |
| 2955 | memset(&migrate, 0, sizeof(migrate)); |
| 2956 | migrate.namelen = res->lockname.len; |
| 2957 | memcpy(migrate.name, res->lockname.name, migrate.namelen); |
| 2958 | migrate.new_master = new_master; |
| 2959 | migrate.master = master; |
| 2960 | |
| 2961 | ret = 0; |
| 2962 | |
| 2963 | /* send message to all nodes, except the master and myself */ |
| 2964 | while ((nodenum = dlm_node_iter_next(iter)) >= 0) { |
| 2965 | if (nodenum == master || |
| 2966 | nodenum == new_master) |
| 2967 | continue; |
| 2968 | |
| 2969 | ret = o2net_send_message(DLM_MIGRATE_REQUEST_MSG, dlm->key, |
| 2970 | &migrate, sizeof(migrate), nodenum, |
| 2971 | &status); |
| 2972 | if (ret < 0) |
| 2973 | mlog_errno(ret); |
| 2974 | else if (status < 0) { |
| 2975 | mlog(0, "migrate request (node %u) returned %d!\n", |
| 2976 | nodenum, status); |
| 2977 | ret = status; |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 2978 | } else if (status == DLM_MIGRATE_RESPONSE_MASTERY_REF) { |
| 2979 | /* during the migration request we short-circuited |
| 2980 | * the mastery of the lockres. make sure we have |
| 2981 | * a mastery ref for nodenum */ |
| 2982 | mlog(0, "%s:%.*s: need ref for node %u\n", |
| 2983 | dlm->name, res->lockname.len, res->lockname.name, |
| 2984 | nodenum); |
| 2985 | spin_lock(&res->spinlock); |
| 2986 | dlm_lockres_set_refmap_bit(nodenum, res); |
| 2987 | spin_unlock(&res->spinlock); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 2988 | } |
| 2989 | } |
| 2990 | |
| 2991 | if (ret < 0) |
| 2992 | mlog_errno(ret); |
| 2993 | |
| 2994 | mlog(0, "returning ret=%d\n", ret); |
| 2995 | return ret; |
| 2996 | } |
| 2997 | |
| 2998 | |
| 2999 | /* if there is an existing mle for this lockres, we now know who the master is. |
| 3000 | * (the one who sent us *this* message) we can clear it up right away. |
| 3001 | * since the process that put the mle on the list still has a reference to it, |
| 3002 | * we can unhash it now, set the master and wake the process. as a result, |
| 3003 | * we will have no mle in the list to start with. now we can add an mle for |
| 3004 | * the migration and this should be the only one found for those scanning the |
| 3005 | * list. */ |
Kurt Hackel | d74c980 | 2007-01-17 17:04:25 -0800 | [diff] [blame] | 3006 | int dlm_migrate_request_handler(struct o2net_msg *msg, u32 len, void *data, |
| 3007 | void **ret_data) |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 3008 | { |
| 3009 | struct dlm_ctxt *dlm = data; |
| 3010 | struct dlm_lock_resource *res = NULL; |
| 3011 | struct dlm_migrate_request *migrate = (struct dlm_migrate_request *) msg->buf; |
| 3012 | struct dlm_master_list_entry *mle = NULL, *oldmle = NULL; |
| 3013 | const char *name; |
Mark Fasheh | a3d3329 | 2006-03-09 17:55:56 -0800 | [diff] [blame] | 3014 | unsigned int namelen, hash; |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 3015 | int ret = 0; |
| 3016 | |
| 3017 | if (!dlm_grab(dlm)) |
| 3018 | return -EINVAL; |
| 3019 | |
| 3020 | name = migrate->name; |
| 3021 | namelen = migrate->namelen; |
Mark Fasheh | a3d3329 | 2006-03-09 17:55:56 -0800 | [diff] [blame] | 3022 | hash = dlm_lockid_hash(name, namelen); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 3023 | |
| 3024 | /* preallocate.. if this fails, abort */ |
| 3025 | mle = (struct dlm_master_list_entry *) kmem_cache_alloc(dlm_mle_cache, |
Kurt Hackel | ad8100e | 2006-05-01 14:25:21 -0700 | [diff] [blame] | 3026 | GFP_NOFS); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 3027 | |
| 3028 | if (!mle) { |
| 3029 | ret = -ENOMEM; |
| 3030 | goto leave; |
| 3031 | } |
| 3032 | |
| 3033 | /* check for pre-existing lock */ |
| 3034 | spin_lock(&dlm->spinlock); |
Mark Fasheh | a3d3329 | 2006-03-09 17:55:56 -0800 | [diff] [blame] | 3035 | res = __dlm_lookup_lockres(dlm, name, namelen, hash); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 3036 | spin_lock(&dlm->master_lock); |
| 3037 | |
| 3038 | if (res) { |
| 3039 | spin_lock(&res->spinlock); |
| 3040 | if (res->state & DLM_LOCK_RES_RECOVERING) { |
| 3041 | /* if all is working ok, this can only mean that we got |
| 3042 | * a migrate request from a node that we now see as |
| 3043 | * dead. what can we do here? drop it to the floor? */ |
| 3044 | spin_unlock(&res->spinlock); |
| 3045 | mlog(ML_ERROR, "Got a migrate request, but the " |
| 3046 | "lockres is marked as recovering!"); |
| 3047 | kmem_cache_free(dlm_mle_cache, mle); |
| 3048 | ret = -EINVAL; /* need a better solution */ |
| 3049 | goto unlock; |
| 3050 | } |
| 3051 | res->state |= DLM_LOCK_RES_MIGRATING; |
| 3052 | spin_unlock(&res->spinlock); |
| 3053 | } |
| 3054 | |
| 3055 | /* ignore status. only nonzero status would BUG. */ |
| 3056 | ret = dlm_add_migration_mle(dlm, res, mle, &oldmle, |
| 3057 | name, namelen, |
| 3058 | migrate->new_master, |
| 3059 | migrate->master); |
| 3060 | |
| 3061 | unlock: |
| 3062 | spin_unlock(&dlm->master_lock); |
| 3063 | spin_unlock(&dlm->spinlock); |
| 3064 | |
| 3065 | if (oldmle) { |
| 3066 | /* master is known, detach if not already detached */ |
| 3067 | dlm_mle_detach_hb_events(dlm, oldmle); |
| 3068 | dlm_put_mle(oldmle); |
| 3069 | } |
| 3070 | |
| 3071 | if (res) |
| 3072 | dlm_lockres_put(res); |
| 3073 | leave: |
| 3074 | dlm_put(dlm); |
| 3075 | return ret; |
| 3076 | } |
| 3077 | |
| 3078 | /* must be holding dlm->spinlock and dlm->master_lock |
| 3079 | * when adding a migration mle, we can clear any other mles |
| 3080 | * in the master list because we know with certainty that |
| 3081 | * the master is "master". so we remove any old mle from |
| 3082 | * the list after setting it's master field, and then add |
| 3083 | * the new migration mle. this way we can hold with the rule |
| 3084 | * of having only one mle for a given lock name at all times. */ |
| 3085 | static int dlm_add_migration_mle(struct dlm_ctxt *dlm, |
| 3086 | struct dlm_lock_resource *res, |
| 3087 | struct dlm_master_list_entry *mle, |
| 3088 | struct dlm_master_list_entry **oldmle, |
| 3089 | const char *name, unsigned int namelen, |
| 3090 | u8 new_master, u8 master) |
| 3091 | { |
| 3092 | int found; |
| 3093 | int ret = 0; |
| 3094 | |
| 3095 | *oldmle = NULL; |
| 3096 | |
| 3097 | mlog_entry_void(); |
| 3098 | |
| 3099 | assert_spin_locked(&dlm->spinlock); |
| 3100 | assert_spin_locked(&dlm->master_lock); |
| 3101 | |
| 3102 | /* caller is responsible for any ref taken here on oldmle */ |
| 3103 | found = dlm_find_mle(dlm, oldmle, (char *)name, namelen); |
| 3104 | if (found) { |
| 3105 | struct dlm_master_list_entry *tmp = *oldmle; |
| 3106 | spin_lock(&tmp->spinlock); |
| 3107 | if (tmp->type == DLM_MLE_MIGRATION) { |
| 3108 | if (master == dlm->node_num) { |
| 3109 | /* ah another process raced me to it */ |
| 3110 | mlog(0, "tried to migrate %.*s, but some " |
| 3111 | "process beat me to it\n", |
| 3112 | namelen, name); |
| 3113 | ret = -EEXIST; |
| 3114 | } else { |
| 3115 | /* bad. 2 NODES are trying to migrate! */ |
| 3116 | mlog(ML_ERROR, "migration error mle: " |
| 3117 | "master=%u new_master=%u // request: " |
| 3118 | "master=%u new_master=%u // " |
| 3119 | "lockres=%.*s\n", |
| 3120 | tmp->master, tmp->new_master, |
| 3121 | master, new_master, |
| 3122 | namelen, name); |
| 3123 | BUG(); |
| 3124 | } |
| 3125 | } else { |
| 3126 | /* this is essentially what assert_master does */ |
| 3127 | tmp->master = master; |
| 3128 | atomic_set(&tmp->woken, 1); |
| 3129 | wake_up(&tmp->wq); |
| 3130 | /* remove it from the list so that only one |
| 3131 | * mle will be found */ |
| 3132 | list_del_init(&tmp->list); |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 3133 | /* this was obviously WRONG. mle is uninited here. should be tmp. */ |
| 3134 | __dlm_mle_detach_hb_events(dlm, tmp); |
| 3135 | ret = DLM_MIGRATE_RESPONSE_MASTERY_REF; |
| 3136 | mlog(0, "%s:%.*s: master=%u, newmaster=%u, " |
| 3137 | "telling master to get ref for cleared out mle " |
| 3138 | "during migration\n", dlm->name, namelen, name, |
| 3139 | master, new_master); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 3140 | } |
| 3141 | spin_unlock(&tmp->spinlock); |
| 3142 | } |
| 3143 | |
| 3144 | /* now add a migration mle to the tail of the list */ |
| 3145 | dlm_init_mle(mle, DLM_MLE_MIGRATION, dlm, res, name, namelen); |
| 3146 | mle->new_master = new_master; |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 3147 | /* the new master will be sending an assert master for this. |
| 3148 | * at that point we will get the refmap reference */ |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 3149 | mle->master = master; |
| 3150 | /* do this for consistency with other mle types */ |
| 3151 | set_bit(new_master, mle->maybe_map); |
| 3152 | list_add(&mle->list, &dlm->master_list); |
| 3153 | |
| 3154 | return ret; |
| 3155 | } |
| 3156 | |
| 3157 | |
| 3158 | void dlm_clean_master_list(struct dlm_ctxt *dlm, u8 dead_node) |
| 3159 | { |
Christoph Hellwig | 800deef | 2007-05-17 16:03:13 +0200 | [diff] [blame] | 3160 | struct dlm_master_list_entry *mle, *next; |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 3161 | struct dlm_lock_resource *res; |
Mark Fasheh | a3d3329 | 2006-03-09 17:55:56 -0800 | [diff] [blame] | 3162 | unsigned int hash; |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 3163 | |
| 3164 | mlog_entry("dlm=%s, dead node=%u\n", dlm->name, dead_node); |
| 3165 | top: |
| 3166 | assert_spin_locked(&dlm->spinlock); |
| 3167 | |
| 3168 | /* clean the master list */ |
| 3169 | spin_lock(&dlm->master_lock); |
Christoph Hellwig | 800deef | 2007-05-17 16:03:13 +0200 | [diff] [blame] | 3170 | list_for_each_entry_safe(mle, next, &dlm->master_list, list) { |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 3171 | BUG_ON(mle->type != DLM_MLE_BLOCK && |
| 3172 | mle->type != DLM_MLE_MASTER && |
| 3173 | mle->type != DLM_MLE_MIGRATION); |
| 3174 | |
| 3175 | /* MASTER mles are initiated locally. the waiting |
| 3176 | * process will notice the node map change |
| 3177 | * shortly. let that happen as normal. */ |
| 3178 | if (mle->type == DLM_MLE_MASTER) |
| 3179 | continue; |
| 3180 | |
| 3181 | |
| 3182 | /* BLOCK mles are initiated by other nodes. |
| 3183 | * need to clean up if the dead node would have |
| 3184 | * been the master. */ |
| 3185 | if (mle->type == DLM_MLE_BLOCK) { |
| 3186 | int bit; |
| 3187 | |
| 3188 | spin_lock(&mle->spinlock); |
| 3189 | bit = find_next_bit(mle->maybe_map, O2NM_MAX_NODES, 0); |
| 3190 | if (bit != dead_node) { |
| 3191 | mlog(0, "mle found, but dead node %u would " |
| 3192 | "not have been master\n", dead_node); |
| 3193 | spin_unlock(&mle->spinlock); |
| 3194 | } else { |
| 3195 | /* must drop the refcount by one since the |
| 3196 | * assert_master will never arrive. this |
| 3197 | * may result in the mle being unlinked and |
| 3198 | * freed, but there may still be a process |
| 3199 | * waiting in the dlmlock path which is fine. */ |
Kurt Hackel | 3b3b84a | 2006-05-01 14:31:37 -0700 | [diff] [blame] | 3200 | mlog(0, "node %u was expected master\n", |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 3201 | dead_node); |
| 3202 | atomic_set(&mle->woken, 1); |
| 3203 | spin_unlock(&mle->spinlock); |
| 3204 | wake_up(&mle->wq); |
Kurt Hackel | f671c09 | 2006-02-14 11:45:21 -0800 | [diff] [blame] | 3205 | /* do not need events any longer, so detach |
| 3206 | * from heartbeat */ |
| 3207 | __dlm_mle_detach_hb_events(dlm, mle); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 3208 | __dlm_put_mle(mle); |
| 3209 | } |
| 3210 | continue; |
| 3211 | } |
| 3212 | |
| 3213 | /* everything else is a MIGRATION mle */ |
| 3214 | |
| 3215 | /* the rule for MIGRATION mles is that the master |
| 3216 | * becomes UNKNOWN if *either* the original or |
| 3217 | * the new master dies. all UNKNOWN lockreses |
| 3218 | * are sent to whichever node becomes the recovery |
| 3219 | * master. the new master is responsible for |
| 3220 | * determining if there is still a master for |
| 3221 | * this lockres, or if he needs to take over |
| 3222 | * mastery. either way, this node should expect |
| 3223 | * another message to resolve this. */ |
| 3224 | if (mle->master != dead_node && |
| 3225 | mle->new_master != dead_node) |
| 3226 | continue; |
| 3227 | |
| 3228 | /* if we have reached this point, this mle needs to |
| 3229 | * be removed from the list and freed. */ |
| 3230 | |
| 3231 | /* remove from the list early. NOTE: unlinking |
| 3232 | * list_head while in list_for_each_safe */ |
Kurt Hackel | da01ad055 | 2006-04-27 18:53:04 -0700 | [diff] [blame] | 3233 | __dlm_mle_detach_hb_events(dlm, mle); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 3234 | spin_lock(&mle->spinlock); |
| 3235 | list_del_init(&mle->list); |
| 3236 | atomic_set(&mle->woken, 1); |
| 3237 | spin_unlock(&mle->spinlock); |
| 3238 | wake_up(&mle->wq); |
| 3239 | |
Kurt Hackel | aa85235 | 2006-04-27 19:04:49 -0700 | [diff] [blame] | 3240 | mlog(0, "%s: node %u died during migration from " |
| 3241 | "%u to %u!\n", dlm->name, dead_node, |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 3242 | mle->master, mle->new_master); |
| 3243 | /* if there is a lockres associated with this |
| 3244 | * mle, find it and set its owner to UNKNOWN */ |
Mark Fasheh | a3d3329 | 2006-03-09 17:55:56 -0800 | [diff] [blame] | 3245 | hash = dlm_lockid_hash(mle->u.name.name, mle->u.name.len); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 3246 | res = __dlm_lookup_lockres(dlm, mle->u.name.name, |
Mark Fasheh | a3d3329 | 2006-03-09 17:55:56 -0800 | [diff] [blame] | 3247 | mle->u.name.len, hash); |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 3248 | if (res) { |
| 3249 | /* unfortunately if we hit this rare case, our |
| 3250 | * lock ordering is messed. we need to drop |
| 3251 | * the master lock so that we can take the |
| 3252 | * lockres lock, meaning that we will have to |
| 3253 | * restart from the head of list. */ |
| 3254 | spin_unlock(&dlm->master_lock); |
| 3255 | |
| 3256 | /* move lockres onto recovery list */ |
| 3257 | spin_lock(&res->spinlock); |
| 3258 | dlm_set_lockres_owner(dlm, res, |
| 3259 | DLM_LOCK_RES_OWNER_UNKNOWN); |
| 3260 | dlm_move_lockres_to_recovery_list(dlm, res); |
| 3261 | spin_unlock(&res->spinlock); |
| 3262 | dlm_lockres_put(res); |
| 3263 | |
Kurt Hackel | f671c09 | 2006-02-14 11:45:21 -0800 | [diff] [blame] | 3264 | /* about to get rid of mle, detach from heartbeat */ |
| 3265 | __dlm_mle_detach_hb_events(dlm, mle); |
| 3266 | |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 3267 | /* dump the mle */ |
| 3268 | spin_lock(&dlm->master_lock); |
| 3269 | __dlm_put_mle(mle); |
| 3270 | spin_unlock(&dlm->master_lock); |
| 3271 | |
| 3272 | /* restart */ |
| 3273 | goto top; |
| 3274 | } |
| 3275 | |
| 3276 | /* this may be the last reference */ |
| 3277 | __dlm_put_mle(mle); |
| 3278 | } |
| 3279 | spin_unlock(&dlm->master_lock); |
| 3280 | } |
| 3281 | |
| 3282 | |
| 3283 | int dlm_finish_migration(struct dlm_ctxt *dlm, struct dlm_lock_resource *res, |
| 3284 | u8 old_master) |
| 3285 | { |
| 3286 | struct dlm_node_iter iter; |
| 3287 | int ret = 0; |
| 3288 | |
| 3289 | spin_lock(&dlm->spinlock); |
| 3290 | dlm_node_iter_init(dlm->domain_map, &iter); |
| 3291 | clear_bit(old_master, iter.node_map); |
| 3292 | clear_bit(dlm->node_num, iter.node_map); |
| 3293 | spin_unlock(&dlm->spinlock); |
| 3294 | |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 3295 | /* ownership of the lockres is changing. account for the |
| 3296 | * mastery reference here since old_master will briefly have |
| 3297 | * a reference after the migration completes */ |
| 3298 | spin_lock(&res->spinlock); |
| 3299 | dlm_lockres_set_refmap_bit(old_master, res); |
| 3300 | spin_unlock(&res->spinlock); |
| 3301 | |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 3302 | mlog(0, "now time to do a migrate request to other nodes\n"); |
| 3303 | ret = dlm_do_migrate_request(dlm, res, old_master, |
| 3304 | dlm->node_num, &iter); |
| 3305 | if (ret < 0) { |
| 3306 | mlog_errno(ret); |
| 3307 | goto leave; |
| 3308 | } |
| 3309 | |
| 3310 | mlog(0, "doing assert master of %.*s to all except the original node\n", |
| 3311 | res->lockname.len, res->lockname.name); |
| 3312 | /* this call now finishes out the nodemap |
| 3313 | * even if one or more nodes die */ |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 3314 | ret = dlm_do_assert_master(dlm, res, iter.node_map, |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 3315 | DLM_ASSERT_MASTER_FINISH_MIGRATION); |
| 3316 | if (ret < 0) { |
| 3317 | /* no longer need to retry. all living nodes contacted. */ |
| 3318 | mlog_errno(ret); |
| 3319 | ret = 0; |
| 3320 | } |
| 3321 | |
| 3322 | memset(iter.node_map, 0, sizeof(iter.node_map)); |
| 3323 | set_bit(old_master, iter.node_map); |
| 3324 | mlog(0, "doing assert master of %.*s back to %u\n", |
| 3325 | res->lockname.len, res->lockname.name, old_master); |
Kurt Hackel | ba2bf21 | 2006-12-01 14:47:20 -0800 | [diff] [blame] | 3326 | ret = dlm_do_assert_master(dlm, res, iter.node_map, |
Kurt Hackel | 6714d8e | 2005-12-15 14:31:23 -0800 | [diff] [blame] | 3327 | DLM_ASSERT_MASTER_FINISH_MIGRATION); |
| 3328 | if (ret < 0) { |
| 3329 | mlog(0, "assert master to original master failed " |
| 3330 | "with %d.\n", ret); |
| 3331 | /* the only nonzero status here would be because of |
| 3332 | * a dead original node. we're done. */ |
| 3333 | ret = 0; |
| 3334 | } |
| 3335 | |
| 3336 | /* all done, set the owner, clear the flag */ |
| 3337 | spin_lock(&res->spinlock); |
| 3338 | dlm_set_lockres_owner(dlm, res, dlm->node_num); |
| 3339 | res->state &= ~DLM_LOCK_RES_MIGRATING; |
| 3340 | spin_unlock(&res->spinlock); |
| 3341 | /* re-dirty it on the new master */ |
| 3342 | dlm_kick_thread(dlm, res); |
| 3343 | wake_up(&res->wq); |
| 3344 | leave: |
| 3345 | return ret; |
| 3346 | } |
| 3347 | |
| 3348 | /* |
| 3349 | * LOCKRES AST REFCOUNT |
| 3350 | * this is integral to migration |
| 3351 | */ |
| 3352 | |
| 3353 | /* for future intent to call an ast, reserve one ahead of time. |
| 3354 | * this should be called only after waiting on the lockres |
| 3355 | * with dlm_wait_on_lockres, and while still holding the |
| 3356 | * spinlock after the call. */ |
| 3357 | void __dlm_lockres_reserve_ast(struct dlm_lock_resource *res) |
| 3358 | { |
| 3359 | assert_spin_locked(&res->spinlock); |
| 3360 | if (res->state & DLM_LOCK_RES_MIGRATING) { |
| 3361 | __dlm_print_one_lock_resource(res); |
| 3362 | } |
| 3363 | BUG_ON(res->state & DLM_LOCK_RES_MIGRATING); |
| 3364 | |
| 3365 | atomic_inc(&res->asts_reserved); |
| 3366 | } |
| 3367 | |
| 3368 | /* |
| 3369 | * used to drop the reserved ast, either because it went unused, |
| 3370 | * or because the ast/bast was actually called. |
| 3371 | * |
| 3372 | * also, if there is a pending migration on this lockres, |
| 3373 | * and this was the last pending ast on the lockres, |
| 3374 | * atomically set the MIGRATING flag before we drop the lock. |
| 3375 | * this is how we ensure that migration can proceed with no |
| 3376 | * asts in progress. note that it is ok if the state of the |
| 3377 | * queues is such that a lock should be granted in the future |
| 3378 | * or that a bast should be fired, because the new master will |
| 3379 | * shuffle the lists on this lockres as soon as it is migrated. |
| 3380 | */ |
| 3381 | void dlm_lockres_release_ast(struct dlm_ctxt *dlm, |
| 3382 | struct dlm_lock_resource *res) |
| 3383 | { |
| 3384 | if (!atomic_dec_and_lock(&res->asts_reserved, &res->spinlock)) |
| 3385 | return; |
| 3386 | |
| 3387 | if (!res->migration_pending) { |
| 3388 | spin_unlock(&res->spinlock); |
| 3389 | return; |
| 3390 | } |
| 3391 | |
| 3392 | BUG_ON(res->state & DLM_LOCK_RES_MIGRATING); |
| 3393 | res->migration_pending = 0; |
| 3394 | res->state |= DLM_LOCK_RES_MIGRATING; |
| 3395 | spin_unlock(&res->spinlock); |
| 3396 | wake_up(&res->wq); |
| 3397 | wake_up(&dlm->migration_wq); |
| 3398 | } |