| 1 | /* |
| 2 | * GPL HEADER START |
| 3 | * |
| 4 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify |
| 7 | * it under the terms of the GNU General Public License version 2 only, |
| 8 | * as published by the Free Software Foundation. |
| 9 | * |
| 10 | * This program is distributed in the hope that it will be useful, but |
| 11 | * WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 13 | * General Public License version 2 for more details (a copy is included |
| 14 | * in the LICENSE file that accompanied this code). |
| 15 | * |
| 16 | * You should have received a copy of the GNU General Public License |
| 17 | * version 2 along with this program; If not, see |
| 18 | * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf |
| 19 | * |
| 20 | * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
| 21 | * CA 95054 USA or visit www.sun.com if you need additional information or |
| 22 | * have any questions. |
| 23 | * |
| 24 | * GPL HEADER END |
| 25 | */ |
| 26 | /* |
| 27 | * Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved. |
| 28 | * Use is subject to license terms. |
| 29 | * |
| 30 | * Copyright (c) 2010, 2012, Intel Corporation. |
| 31 | */ |
| 32 | /* |
| 33 | * This file is part of Lustre, http://www.lustre.org/ |
| 34 | * Lustre is a trademark of Sun Microsystems, Inc. |
| 35 | * |
| 36 | * lustre/ldlm/ldlm_lock.c |
| 37 | * |
| 38 | * Author: Peter Braam <braam@clusterfs.com> |
| 39 | * Author: Phil Schwan <phil@clusterfs.com> |
| 40 | */ |
| 41 | |
| 42 | #define DEBUG_SUBSYSTEM S_LDLM |
| 43 | |
| 44 | # include <linux/libcfs/libcfs.h> |
| 45 | # include <linux/lustre_intent.h> |
| 46 | |
| 47 | #include <obd_class.h> |
| 48 | #include "ldlm_internal.h" |
| 49 | |
| 50 | /* lock types */ |
| 51 | char *ldlm_lockname[] = { |
| 52 | [0] = "--", |
| 53 | [LCK_EX] = "EX", |
| 54 | [LCK_PW] = "PW", |
| 55 | [LCK_PR] = "PR", |
| 56 | [LCK_CW] = "CW", |
| 57 | [LCK_CR] = "CR", |
| 58 | [LCK_NL] = "NL", |
| 59 | [LCK_GROUP] = "GROUP", |
| 60 | [LCK_COS] = "COS", |
| 61 | }; |
| 62 | EXPORT_SYMBOL(ldlm_lockname); |
| 63 | |
| 64 | char *ldlm_typename[] = { |
| 65 | [LDLM_PLAIN] = "PLN", |
| 66 | [LDLM_EXTENT] = "EXT", |
| 67 | [LDLM_FLOCK] = "FLK", |
| 68 | [LDLM_IBITS] = "IBT", |
| 69 | }; |
| 70 | EXPORT_SYMBOL(ldlm_typename); |
| 71 | |
| 72 | static ldlm_policy_wire_to_local_t ldlm_policy_wire18_to_local[] = { |
| 73 | [LDLM_PLAIN - LDLM_MIN_TYPE] = ldlm_plain_policy_wire_to_local, |
| 74 | [LDLM_EXTENT - LDLM_MIN_TYPE] = ldlm_extent_policy_wire_to_local, |
| 75 | [LDLM_FLOCK - LDLM_MIN_TYPE] = ldlm_flock_policy_wire18_to_local, |
| 76 | [LDLM_IBITS - LDLM_MIN_TYPE] = ldlm_ibits_policy_wire_to_local, |
| 77 | }; |
| 78 | |
| 79 | static ldlm_policy_wire_to_local_t ldlm_policy_wire21_to_local[] = { |
| 80 | [LDLM_PLAIN - LDLM_MIN_TYPE] = ldlm_plain_policy_wire_to_local, |
| 81 | [LDLM_EXTENT - LDLM_MIN_TYPE] = ldlm_extent_policy_wire_to_local, |
| 82 | [LDLM_FLOCK - LDLM_MIN_TYPE] = ldlm_flock_policy_wire21_to_local, |
| 83 | [LDLM_IBITS - LDLM_MIN_TYPE] = ldlm_ibits_policy_wire_to_local, |
| 84 | }; |
| 85 | |
| 86 | static ldlm_policy_local_to_wire_t ldlm_policy_local_to_wire[] = { |
| 87 | [LDLM_PLAIN - LDLM_MIN_TYPE] = ldlm_plain_policy_local_to_wire, |
| 88 | [LDLM_EXTENT - LDLM_MIN_TYPE] = ldlm_extent_policy_local_to_wire, |
| 89 | [LDLM_FLOCK - LDLM_MIN_TYPE] = ldlm_flock_policy_local_to_wire, |
| 90 | [LDLM_IBITS - LDLM_MIN_TYPE] = ldlm_ibits_policy_local_to_wire, |
| 91 | }; |
| 92 | |
| 93 | /** |
| 94 | * Converts lock policy from local format to on the wire lock_desc format |
| 95 | */ |
| 96 | void ldlm_convert_policy_to_wire(ldlm_type_t type, |
| 97 | const ldlm_policy_data_t *lpolicy, |
| 98 | ldlm_wire_policy_data_t *wpolicy) |
| 99 | { |
| 100 | ldlm_policy_local_to_wire_t convert; |
| 101 | |
| 102 | convert = ldlm_policy_local_to_wire[type - LDLM_MIN_TYPE]; |
| 103 | |
| 104 | convert(lpolicy, wpolicy); |
| 105 | } |
| 106 | |
| 107 | /** |
| 108 | * Converts lock policy from on the wire lock_desc format to local format |
| 109 | */ |
| 110 | void ldlm_convert_policy_to_local(struct obd_export *exp, ldlm_type_t type, |
| 111 | const ldlm_wire_policy_data_t *wpolicy, |
| 112 | ldlm_policy_data_t *lpolicy) |
| 113 | { |
| 114 | ldlm_policy_wire_to_local_t convert; |
| 115 | int new_client; |
| 116 | |
| 117 | /** some badness for 2.0.0 clients, but 2.0.0 isn't supported */ |
| 118 | new_client = (exp_connect_flags(exp) & OBD_CONNECT_FULL20) != 0; |
| 119 | if (new_client) |
| 120 | convert = ldlm_policy_wire21_to_local[type - LDLM_MIN_TYPE]; |
| 121 | else |
| 122 | convert = ldlm_policy_wire18_to_local[type - LDLM_MIN_TYPE]; |
| 123 | |
| 124 | convert(wpolicy, lpolicy); |
| 125 | } |
| 126 | |
| 127 | char *ldlm_it2str(int it) |
| 128 | { |
| 129 | switch (it) { |
| 130 | case IT_OPEN: |
| 131 | return "open"; |
| 132 | case IT_CREAT: |
| 133 | return "creat"; |
| 134 | case (IT_OPEN | IT_CREAT): |
| 135 | return "open|creat"; |
| 136 | case IT_READDIR: |
| 137 | return "readdir"; |
| 138 | case IT_GETATTR: |
| 139 | return "getattr"; |
| 140 | case IT_LOOKUP: |
| 141 | return "lookup"; |
| 142 | case IT_UNLINK: |
| 143 | return "unlink"; |
| 144 | case IT_GETXATTR: |
| 145 | return "getxattr"; |
| 146 | case IT_LAYOUT: |
| 147 | return "layout"; |
| 148 | default: |
| 149 | CERROR("Unknown intent %d\n", it); |
| 150 | return "UNKNOWN"; |
| 151 | } |
| 152 | } |
| 153 | EXPORT_SYMBOL(ldlm_it2str); |
| 154 | |
| 155 | extern struct kmem_cache *ldlm_lock_slab; |
| 156 | |
| 157 | |
| 158 | void ldlm_register_intent(struct ldlm_namespace *ns, ldlm_res_policy arg) |
| 159 | { |
| 160 | ns->ns_policy = arg; |
| 161 | } |
| 162 | EXPORT_SYMBOL(ldlm_register_intent); |
| 163 | |
| 164 | /* |
| 165 | * REFCOUNTED LOCK OBJECTS |
| 166 | */ |
| 167 | |
| 168 | |
| 169 | /** |
| 170 | * Get a reference on a lock. |
| 171 | * |
| 172 | * Lock refcounts, during creation: |
| 173 | * - one special one for allocation, dec'd only once in destroy |
| 174 | * - one for being a lock that's in-use |
| 175 | * - one for the addref associated with a new lock |
| 176 | */ |
| 177 | struct ldlm_lock *ldlm_lock_get(struct ldlm_lock *lock) |
| 178 | { |
| 179 | atomic_inc(&lock->l_refc); |
| 180 | return lock; |
| 181 | } |
| 182 | EXPORT_SYMBOL(ldlm_lock_get); |
| 183 | |
| 184 | /** |
| 185 | * Release lock reference. |
| 186 | * |
| 187 | * Also frees the lock if it was last reference. |
| 188 | */ |
| 189 | void ldlm_lock_put(struct ldlm_lock *lock) |
| 190 | { |
| 191 | LASSERT(lock->l_resource != LP_POISON); |
| 192 | LASSERT(atomic_read(&lock->l_refc) > 0); |
| 193 | if (atomic_dec_and_test(&lock->l_refc)) { |
| 194 | struct ldlm_resource *res; |
| 195 | |
| 196 | LDLM_DEBUG(lock, |
| 197 | "final lock_put on destroyed lock, freeing it."); |
| 198 | |
| 199 | res = lock->l_resource; |
| 200 | LASSERT(lock->l_flags & LDLM_FL_DESTROYED); |
| 201 | LASSERT(list_empty(&lock->l_res_link)); |
| 202 | LASSERT(list_empty(&lock->l_pending_chain)); |
| 203 | |
| 204 | lprocfs_counter_decr(ldlm_res_to_ns(res)->ns_stats, |
| 205 | LDLM_NSS_LOCKS); |
| 206 | lu_ref_del(&res->lr_reference, "lock", lock); |
| 207 | ldlm_resource_putref(res); |
| 208 | lock->l_resource = NULL; |
| 209 | if (lock->l_export) { |
| 210 | class_export_lock_put(lock->l_export, lock); |
| 211 | lock->l_export = NULL; |
| 212 | } |
| 213 | |
| 214 | if (lock->l_lvb_data != NULL) |
| 215 | OBD_FREE(lock->l_lvb_data, lock->l_lvb_len); |
| 216 | |
| 217 | ldlm_interval_free(ldlm_interval_detach(lock)); |
| 218 | lu_ref_fini(&lock->l_reference); |
| 219 | OBD_FREE_RCU(lock, sizeof(*lock), &lock->l_handle); |
| 220 | } |
| 221 | } |
| 222 | EXPORT_SYMBOL(ldlm_lock_put); |
| 223 | |
| 224 | /** |
| 225 | * Removes LDLM lock \a lock from LRU. Assumes LRU is already locked. |
| 226 | */ |
| 227 | int ldlm_lock_remove_from_lru_nolock(struct ldlm_lock *lock) |
| 228 | { |
| 229 | int rc = 0; |
| 230 | if (!list_empty(&lock->l_lru)) { |
| 231 | struct ldlm_namespace *ns = ldlm_lock_to_ns(lock); |
| 232 | |
| 233 | LASSERT(lock->l_resource->lr_type != LDLM_FLOCK); |
| 234 | list_del_init(&lock->l_lru); |
| 235 | if (lock->l_flags & LDLM_FL_SKIPPED) |
| 236 | lock->l_flags &= ~LDLM_FL_SKIPPED; |
| 237 | LASSERT(ns->ns_nr_unused > 0); |
| 238 | ns->ns_nr_unused--; |
| 239 | rc = 1; |
| 240 | } |
| 241 | return rc; |
| 242 | } |
| 243 | |
| 244 | /** |
| 245 | * Removes LDLM lock \a lock from LRU. Obtains the LRU lock first. |
| 246 | */ |
| 247 | int ldlm_lock_remove_from_lru(struct ldlm_lock *lock) |
| 248 | { |
| 249 | struct ldlm_namespace *ns = ldlm_lock_to_ns(lock); |
| 250 | int rc; |
| 251 | |
| 252 | if (lock->l_flags & LDLM_FL_NS_SRV) { |
| 253 | LASSERT(list_empty(&lock->l_lru)); |
| 254 | return 0; |
| 255 | } |
| 256 | |
| 257 | spin_lock(&ns->ns_lock); |
| 258 | rc = ldlm_lock_remove_from_lru_nolock(lock); |
| 259 | spin_unlock(&ns->ns_lock); |
| 260 | return rc; |
| 261 | } |
| 262 | |
| 263 | /** |
| 264 | * Adds LDLM lock \a lock to namespace LRU. Assumes LRU is already locked. |
| 265 | */ |
| 266 | void ldlm_lock_add_to_lru_nolock(struct ldlm_lock *lock) |
| 267 | { |
| 268 | struct ldlm_namespace *ns = ldlm_lock_to_ns(lock); |
| 269 | |
| 270 | lock->l_last_used = cfs_time_current(); |
| 271 | LASSERT(list_empty(&lock->l_lru)); |
| 272 | LASSERT(lock->l_resource->lr_type != LDLM_FLOCK); |
| 273 | list_add_tail(&lock->l_lru, &ns->ns_unused_list); |
| 274 | LASSERT(ns->ns_nr_unused >= 0); |
| 275 | ns->ns_nr_unused++; |
| 276 | } |
| 277 | |
| 278 | /** |
| 279 | * Adds LDLM lock \a lock to namespace LRU. Obtains necessary LRU locks |
| 280 | * first. |
| 281 | */ |
| 282 | void ldlm_lock_add_to_lru(struct ldlm_lock *lock) |
| 283 | { |
| 284 | struct ldlm_namespace *ns = ldlm_lock_to_ns(lock); |
| 285 | |
| 286 | spin_lock(&ns->ns_lock); |
| 287 | ldlm_lock_add_to_lru_nolock(lock); |
| 288 | spin_unlock(&ns->ns_lock); |
| 289 | } |
| 290 | |
| 291 | /** |
| 292 | * Moves LDLM lock \a lock that is already in namespace LRU to the tail of |
| 293 | * the LRU. Performs necessary LRU locking |
| 294 | */ |
| 295 | void ldlm_lock_touch_in_lru(struct ldlm_lock *lock) |
| 296 | { |
| 297 | struct ldlm_namespace *ns = ldlm_lock_to_ns(lock); |
| 298 | |
| 299 | if (lock->l_flags & LDLM_FL_NS_SRV) { |
| 300 | LASSERT(list_empty(&lock->l_lru)); |
| 301 | return; |
| 302 | } |
| 303 | |
| 304 | spin_lock(&ns->ns_lock); |
| 305 | if (!list_empty(&lock->l_lru)) { |
| 306 | ldlm_lock_remove_from_lru_nolock(lock); |
| 307 | ldlm_lock_add_to_lru_nolock(lock); |
| 308 | } |
| 309 | spin_unlock(&ns->ns_lock); |
| 310 | } |
| 311 | |
| 312 | /** |
| 313 | * Helper to destroy a locked lock. |
| 314 | * |
| 315 | * Used by ldlm_lock_destroy and ldlm_lock_destroy_nolock |
| 316 | * Must be called with l_lock and lr_lock held. |
| 317 | * |
| 318 | * Does not actually free the lock data, but rather marks the lock as |
| 319 | * destroyed by setting l_destroyed field in the lock to 1. Destroys a |
| 320 | * handle->lock association too, so that the lock can no longer be found |
| 321 | * and removes the lock from LRU list. Actual lock freeing occurs when |
| 322 | * last lock reference goes away. |
| 323 | * |
| 324 | * Original comment (of some historical value): |
| 325 | * This used to have a 'strict' flag, which recovery would use to mark an |
| 326 | * in-use lock as needing-to-die. Lest I am ever tempted to put it back, I |
| 327 | * shall explain why it's gone: with the new hash table scheme, once you call |
| 328 | * ldlm_lock_destroy, you can never drop your final references on this lock. |
| 329 | * Because it's not in the hash table anymore. -phil |
| 330 | */ |
| 331 | int ldlm_lock_destroy_internal(struct ldlm_lock *lock) |
| 332 | { |
| 333 | if (lock->l_readers || lock->l_writers) { |
| 334 | LDLM_ERROR(lock, "lock still has references"); |
| 335 | LBUG(); |
| 336 | } |
| 337 | |
| 338 | if (!list_empty(&lock->l_res_link)) { |
| 339 | LDLM_ERROR(lock, "lock still on resource"); |
| 340 | LBUG(); |
| 341 | } |
| 342 | |
| 343 | if (lock->l_flags & LDLM_FL_DESTROYED) { |
| 344 | LASSERT(list_empty(&lock->l_lru)); |
| 345 | return 0; |
| 346 | } |
| 347 | lock->l_flags |= LDLM_FL_DESTROYED; |
| 348 | |
| 349 | if (lock->l_export && lock->l_export->exp_lock_hash) { |
| 350 | /* NB: it's safe to call cfs_hash_del() even lock isn't |
| 351 | * in exp_lock_hash. */ |
| 352 | /* In the function below, .hs_keycmp resolves to |
| 353 | * ldlm_export_lock_keycmp() */ |
| 354 | /* coverity[overrun-buffer-val] */ |
| 355 | cfs_hash_del(lock->l_export->exp_lock_hash, |
| 356 | &lock->l_remote_handle, &lock->l_exp_hash); |
| 357 | } |
| 358 | |
| 359 | ldlm_lock_remove_from_lru(lock); |
| 360 | class_handle_unhash(&lock->l_handle); |
| 361 | |
| 362 | #if 0 |
| 363 | /* Wake anyone waiting for this lock */ |
| 364 | /* FIXME: I should probably add yet another flag, instead of using |
| 365 | * l_export to only call this on clients */ |
| 366 | if (lock->l_export) |
| 367 | class_export_put(lock->l_export); |
| 368 | lock->l_export = NULL; |
| 369 | if (lock->l_export && lock->l_completion_ast) |
| 370 | lock->l_completion_ast(lock, 0); |
| 371 | #endif |
| 372 | return 1; |
| 373 | } |
| 374 | |
| 375 | /** |
| 376 | * Destroys a LDLM lock \a lock. Performs necessary locking first. |
| 377 | */ |
| 378 | void ldlm_lock_destroy(struct ldlm_lock *lock) |
| 379 | { |
| 380 | int first; |
| 381 | |
| 382 | lock_res_and_lock(lock); |
| 383 | first = ldlm_lock_destroy_internal(lock); |
| 384 | unlock_res_and_lock(lock); |
| 385 | |
| 386 | /* drop reference from hashtable only for first destroy */ |
| 387 | if (first) { |
| 388 | lu_ref_del(&lock->l_reference, "hash", lock); |
| 389 | LDLM_LOCK_RELEASE(lock); |
| 390 | } |
| 391 | } |
| 392 | |
| 393 | /** |
| 394 | * Destroys a LDLM lock \a lock that is already locked. |
| 395 | */ |
| 396 | void ldlm_lock_destroy_nolock(struct ldlm_lock *lock) |
| 397 | { |
| 398 | int first; |
| 399 | |
| 400 | first = ldlm_lock_destroy_internal(lock); |
| 401 | /* drop reference from hashtable only for first destroy */ |
| 402 | if (first) { |
| 403 | lu_ref_del(&lock->l_reference, "hash", lock); |
| 404 | LDLM_LOCK_RELEASE(lock); |
| 405 | } |
| 406 | } |
| 407 | |
| 408 | /* this is called by portals_handle2object with the handle lock taken */ |
| 409 | static void lock_handle_addref(void *lock) |
| 410 | { |
| 411 | LDLM_LOCK_GET((struct ldlm_lock *)lock); |
| 412 | } |
| 413 | |
| 414 | static void lock_handle_free(void *lock, int size) |
| 415 | { |
| 416 | LASSERT(size == sizeof(struct ldlm_lock)); |
| 417 | OBD_SLAB_FREE(lock, ldlm_lock_slab, size); |
| 418 | } |
| 419 | |
| 420 | struct portals_handle_ops lock_handle_ops = { |
| 421 | .hop_addref = lock_handle_addref, |
| 422 | .hop_free = lock_handle_free, |
| 423 | }; |
| 424 | |
| 425 | /** |
| 426 | * |
| 427 | * Allocate and initialize new lock structure. |
| 428 | * |
| 429 | * usage: pass in a resource on which you have done ldlm_resource_get |
| 430 | * new lock will take over the refcount. |
| 431 | * returns: lock with refcount 2 - one for current caller and one for remote |
| 432 | */ |
| 433 | static struct ldlm_lock *ldlm_lock_new(struct ldlm_resource *resource) |
| 434 | { |
| 435 | struct ldlm_lock *lock; |
| 436 | |
| 437 | if (resource == NULL) |
| 438 | LBUG(); |
| 439 | |
| 440 | OBD_SLAB_ALLOC_PTR_GFP(lock, ldlm_lock_slab, __GFP_IO); |
| 441 | if (lock == NULL) |
| 442 | return NULL; |
| 443 | |
| 444 | spin_lock_init(&lock->l_lock); |
| 445 | lock->l_resource = resource; |
| 446 | lu_ref_add(&resource->lr_reference, "lock", lock); |
| 447 | |
| 448 | atomic_set(&lock->l_refc, 2); |
| 449 | INIT_LIST_HEAD(&lock->l_res_link); |
| 450 | INIT_LIST_HEAD(&lock->l_lru); |
| 451 | INIT_LIST_HEAD(&lock->l_pending_chain); |
| 452 | INIT_LIST_HEAD(&lock->l_bl_ast); |
| 453 | INIT_LIST_HEAD(&lock->l_cp_ast); |
| 454 | INIT_LIST_HEAD(&lock->l_rk_ast); |
| 455 | init_waitqueue_head(&lock->l_waitq); |
| 456 | lock->l_blocking_lock = NULL; |
| 457 | INIT_LIST_HEAD(&lock->l_sl_mode); |
| 458 | INIT_LIST_HEAD(&lock->l_sl_policy); |
| 459 | INIT_HLIST_NODE(&lock->l_exp_hash); |
| 460 | INIT_HLIST_NODE(&lock->l_exp_flock_hash); |
| 461 | |
| 462 | lprocfs_counter_incr(ldlm_res_to_ns(resource)->ns_stats, |
| 463 | LDLM_NSS_LOCKS); |
| 464 | INIT_LIST_HEAD(&lock->l_handle.h_link); |
| 465 | class_handle_hash(&lock->l_handle, &lock_handle_ops); |
| 466 | |
| 467 | lu_ref_init(&lock->l_reference); |
| 468 | lu_ref_add(&lock->l_reference, "hash", lock); |
| 469 | lock->l_callback_timeout = 0; |
| 470 | |
| 471 | #if LUSTRE_TRACKS_LOCK_EXP_REFS |
| 472 | INIT_LIST_HEAD(&lock->l_exp_refs_link); |
| 473 | lock->l_exp_refs_nr = 0; |
| 474 | lock->l_exp_refs_target = NULL; |
| 475 | #endif |
| 476 | INIT_LIST_HEAD(&lock->l_exp_list); |
| 477 | |
| 478 | return lock; |
| 479 | } |
| 480 | |
| 481 | /** |
| 482 | * Moves LDLM lock \a lock to another resource. |
| 483 | * This is used on client when server returns some other lock than requested |
| 484 | * (typically as a result of intent operation) |
| 485 | */ |
| 486 | int ldlm_lock_change_resource(struct ldlm_namespace *ns, struct ldlm_lock *lock, |
| 487 | const struct ldlm_res_id *new_resid) |
| 488 | { |
| 489 | struct ldlm_resource *oldres = lock->l_resource; |
| 490 | struct ldlm_resource *newres; |
| 491 | int type; |
| 492 | |
| 493 | LASSERT(ns_is_client(ns)); |
| 494 | |
| 495 | lock_res_and_lock(lock); |
| 496 | if (memcmp(new_resid, &lock->l_resource->lr_name, |
| 497 | sizeof(lock->l_resource->lr_name)) == 0) { |
| 498 | /* Nothing to do */ |
| 499 | unlock_res_and_lock(lock); |
| 500 | return 0; |
| 501 | } |
| 502 | |
| 503 | LASSERT(new_resid->name[0] != 0); |
| 504 | |
| 505 | /* This function assumes that the lock isn't on any lists */ |
| 506 | LASSERT(list_empty(&lock->l_res_link)); |
| 507 | |
| 508 | type = oldres->lr_type; |
| 509 | unlock_res_and_lock(lock); |
| 510 | |
| 511 | newres = ldlm_resource_get(ns, NULL, new_resid, type, 1); |
| 512 | if (newres == NULL) |
| 513 | return -ENOMEM; |
| 514 | |
| 515 | lu_ref_add(&newres->lr_reference, "lock", lock); |
| 516 | /* |
| 517 | * To flip the lock from the old to the new resource, lock, oldres and |
| 518 | * newres have to be locked. Resource spin-locks are nested within |
| 519 | * lock->l_lock, and are taken in the memory address order to avoid |
| 520 | * dead-locks. |
| 521 | */ |
| 522 | spin_lock(&lock->l_lock); |
| 523 | oldres = lock->l_resource; |
| 524 | if (oldres < newres) { |
| 525 | lock_res(oldres); |
| 526 | lock_res_nested(newres, LRT_NEW); |
| 527 | } else { |
| 528 | lock_res(newres); |
| 529 | lock_res_nested(oldres, LRT_NEW); |
| 530 | } |
| 531 | LASSERT(memcmp(new_resid, &oldres->lr_name, |
| 532 | sizeof oldres->lr_name) != 0); |
| 533 | lock->l_resource = newres; |
| 534 | unlock_res(oldres); |
| 535 | unlock_res_and_lock(lock); |
| 536 | |
| 537 | /* ...and the flowers are still standing! */ |
| 538 | lu_ref_del(&oldres->lr_reference, "lock", lock); |
| 539 | ldlm_resource_putref(oldres); |
| 540 | |
| 541 | return 0; |
| 542 | } |
| 543 | EXPORT_SYMBOL(ldlm_lock_change_resource); |
| 544 | |
| 545 | /** \defgroup ldlm_handles LDLM HANDLES |
| 546 | * Ways to get hold of locks without any addresses. |
| 547 | * @{ |
| 548 | */ |
| 549 | |
| 550 | /** |
| 551 | * Fills in handle for LDLM lock \a lock into supplied \a lockh |
| 552 | * Does not take any references. |
| 553 | */ |
| 554 | void ldlm_lock2handle(const struct ldlm_lock *lock, struct lustre_handle *lockh) |
| 555 | { |
| 556 | lockh->cookie = lock->l_handle.h_cookie; |
| 557 | } |
| 558 | EXPORT_SYMBOL(ldlm_lock2handle); |
| 559 | |
| 560 | /** |
| 561 | * Obtain a lock reference by handle. |
| 562 | * |
| 563 | * if \a flags: atomically get the lock and set the flags. |
| 564 | * Return NULL if flag already set |
| 565 | */ |
| 566 | struct ldlm_lock *__ldlm_handle2lock(const struct lustre_handle *handle, |
| 567 | __u64 flags) |
| 568 | { |
| 569 | struct ldlm_lock *lock; |
| 570 | |
| 571 | LASSERT(handle); |
| 572 | |
| 573 | lock = class_handle2object(handle->cookie); |
| 574 | if (lock == NULL) |
| 575 | return NULL; |
| 576 | |
| 577 | /* It's unlikely but possible that someone marked the lock as |
| 578 | * destroyed after we did handle2object on it */ |
| 579 | if (flags == 0 && ((lock->l_flags & LDLM_FL_DESTROYED)== 0)) { |
| 580 | lu_ref_add(&lock->l_reference, "handle", current); |
| 581 | return lock; |
| 582 | } |
| 583 | |
| 584 | lock_res_and_lock(lock); |
| 585 | |
| 586 | LASSERT(lock->l_resource != NULL); |
| 587 | |
| 588 | lu_ref_add_atomic(&lock->l_reference, "handle", current); |
| 589 | if (unlikely(lock->l_flags & LDLM_FL_DESTROYED)) { |
| 590 | unlock_res_and_lock(lock); |
| 591 | CDEBUG(D_INFO, "lock already destroyed: lock %p\n", lock); |
| 592 | LDLM_LOCK_PUT(lock); |
| 593 | return NULL; |
| 594 | } |
| 595 | |
| 596 | if (flags && (lock->l_flags & flags)) { |
| 597 | unlock_res_and_lock(lock); |
| 598 | LDLM_LOCK_PUT(lock); |
| 599 | return NULL; |
| 600 | } |
| 601 | |
| 602 | if (flags) |
| 603 | lock->l_flags |= flags; |
| 604 | |
| 605 | unlock_res_and_lock(lock); |
| 606 | return lock; |
| 607 | } |
| 608 | EXPORT_SYMBOL(__ldlm_handle2lock); |
| 609 | /** @} ldlm_handles */ |
| 610 | |
| 611 | /** |
| 612 | * Fill in "on the wire" representation for given LDLM lock into supplied |
| 613 | * lock descriptor \a desc structure. |
| 614 | */ |
| 615 | void ldlm_lock2desc(struct ldlm_lock *lock, struct ldlm_lock_desc *desc) |
| 616 | { |
| 617 | struct obd_export *exp = lock->l_export ?: lock->l_conn_export; |
| 618 | |
| 619 | /* INODEBITS_INTEROP: If the other side does not support |
| 620 | * inodebits, reply with a plain lock descriptor. */ |
| 621 | if ((lock->l_resource->lr_type == LDLM_IBITS) && |
| 622 | (exp && !(exp_connect_flags(exp) & OBD_CONNECT_IBITS))) { |
| 623 | /* Make sure all the right bits are set in this lock we |
| 624 | are going to pass to client */ |
| 625 | LASSERTF(lock->l_policy_data.l_inodebits.bits == |
| 626 | (MDS_INODELOCK_LOOKUP | MDS_INODELOCK_UPDATE | |
| 627 | MDS_INODELOCK_LAYOUT), |
| 628 | "Inappropriate inode lock bits during " |
| 629 | "conversion " LPU64 "\n", |
| 630 | lock->l_policy_data.l_inodebits.bits); |
| 631 | |
| 632 | ldlm_res2desc(lock->l_resource, &desc->l_resource); |
| 633 | desc->l_resource.lr_type = LDLM_PLAIN; |
| 634 | |
| 635 | /* Convert "new" lock mode to something old client can |
| 636 | understand */ |
| 637 | if ((lock->l_req_mode == LCK_CR) || |
| 638 | (lock->l_req_mode == LCK_CW)) |
| 639 | desc->l_req_mode = LCK_PR; |
| 640 | else |
| 641 | desc->l_req_mode = lock->l_req_mode; |
| 642 | if ((lock->l_granted_mode == LCK_CR) || |
| 643 | (lock->l_granted_mode == LCK_CW)) { |
| 644 | desc->l_granted_mode = LCK_PR; |
| 645 | } else { |
| 646 | /* We never grant PW/EX locks to clients */ |
| 647 | LASSERT((lock->l_granted_mode != LCK_PW) && |
| 648 | (lock->l_granted_mode != LCK_EX)); |
| 649 | desc->l_granted_mode = lock->l_granted_mode; |
| 650 | } |
| 651 | |
| 652 | /* We do not copy policy here, because there is no |
| 653 | policy for plain locks */ |
| 654 | } else { |
| 655 | ldlm_res2desc(lock->l_resource, &desc->l_resource); |
| 656 | desc->l_req_mode = lock->l_req_mode; |
| 657 | desc->l_granted_mode = lock->l_granted_mode; |
| 658 | ldlm_convert_policy_to_wire(lock->l_resource->lr_type, |
| 659 | &lock->l_policy_data, |
| 660 | &desc->l_policy_data); |
| 661 | } |
| 662 | } |
| 663 | EXPORT_SYMBOL(ldlm_lock2desc); |
| 664 | |
| 665 | /** |
| 666 | * Add a lock to list of conflicting locks to send AST to. |
| 667 | * |
| 668 | * Only add if we have not sent a blocking AST to the lock yet. |
| 669 | */ |
| 670 | void ldlm_add_bl_work_item(struct ldlm_lock *lock, struct ldlm_lock *new, |
| 671 | struct list_head *work_list) |
| 672 | { |
| 673 | if ((lock->l_flags & LDLM_FL_AST_SENT) == 0) { |
| 674 | LDLM_DEBUG(lock, "lock incompatible; sending blocking AST."); |
| 675 | lock->l_flags |= LDLM_FL_AST_SENT; |
| 676 | /* If the enqueuing client said so, tell the AST recipient to |
| 677 | * discard dirty data, rather than writing back. */ |
| 678 | if (new->l_flags & LDLM_FL_AST_DISCARD_DATA) |
| 679 | lock->l_flags |= LDLM_FL_DISCARD_DATA; |
| 680 | LASSERT(list_empty(&lock->l_bl_ast)); |
| 681 | list_add(&lock->l_bl_ast, work_list); |
| 682 | LDLM_LOCK_GET(lock); |
| 683 | LASSERT(lock->l_blocking_lock == NULL); |
| 684 | lock->l_blocking_lock = LDLM_LOCK_GET(new); |
| 685 | } |
| 686 | } |
| 687 | |
| 688 | /** |
| 689 | * Add a lock to list of just granted locks to send completion AST to. |
| 690 | */ |
| 691 | void ldlm_add_cp_work_item(struct ldlm_lock *lock, struct list_head *work_list) |
| 692 | { |
| 693 | if ((lock->l_flags & LDLM_FL_CP_REQD) == 0) { |
| 694 | lock->l_flags |= LDLM_FL_CP_REQD; |
| 695 | LDLM_DEBUG(lock, "lock granted; sending completion AST."); |
| 696 | LASSERT(list_empty(&lock->l_cp_ast)); |
| 697 | list_add(&lock->l_cp_ast, work_list); |
| 698 | LDLM_LOCK_GET(lock); |
| 699 | } |
| 700 | } |
| 701 | |
| 702 | /** |
| 703 | * Aggregator function to add AST work items into a list. Determines |
| 704 | * what sort of an AST work needs to be done and calls the proper |
| 705 | * adding function. |
| 706 | * Must be called with lr_lock held. |
| 707 | */ |
| 708 | void ldlm_add_ast_work_item(struct ldlm_lock *lock, struct ldlm_lock *new, |
| 709 | struct list_head *work_list) |
| 710 | { |
| 711 | check_res_locked(lock->l_resource); |
| 712 | if (new) |
| 713 | ldlm_add_bl_work_item(lock, new, work_list); |
| 714 | else |
| 715 | ldlm_add_cp_work_item(lock, work_list); |
| 716 | } |
| 717 | |
| 718 | /** |
| 719 | * Add specified reader/writer reference to LDLM lock with handle \a lockh. |
| 720 | * r/w reference type is determined by \a mode |
| 721 | * Calls ldlm_lock_addref_internal. |
| 722 | */ |
| 723 | void ldlm_lock_addref(struct lustre_handle *lockh, __u32 mode) |
| 724 | { |
| 725 | struct ldlm_lock *lock; |
| 726 | |
| 727 | lock = ldlm_handle2lock(lockh); |
| 728 | LASSERT(lock != NULL); |
| 729 | ldlm_lock_addref_internal(lock, mode); |
| 730 | LDLM_LOCK_PUT(lock); |
| 731 | } |
| 732 | EXPORT_SYMBOL(ldlm_lock_addref); |
| 733 | |
| 734 | /** |
| 735 | * Helper function. |
| 736 | * Add specified reader/writer reference to LDLM lock \a lock. |
| 737 | * r/w reference type is determined by \a mode |
| 738 | * Removes lock from LRU if it is there. |
| 739 | * Assumes the LDLM lock is already locked. |
| 740 | */ |
| 741 | void ldlm_lock_addref_internal_nolock(struct ldlm_lock *lock, __u32 mode) |
| 742 | { |
| 743 | ldlm_lock_remove_from_lru(lock); |
| 744 | if (mode & (LCK_NL | LCK_CR | LCK_PR)) { |
| 745 | lock->l_readers++; |
| 746 | lu_ref_add_atomic(&lock->l_reference, "reader", lock); |
| 747 | } |
| 748 | if (mode & (LCK_EX | LCK_CW | LCK_PW | LCK_GROUP | LCK_COS)) { |
| 749 | lock->l_writers++; |
| 750 | lu_ref_add_atomic(&lock->l_reference, "writer", lock); |
| 751 | } |
| 752 | LDLM_LOCK_GET(lock); |
| 753 | lu_ref_add_atomic(&lock->l_reference, "user", lock); |
| 754 | LDLM_DEBUG(lock, "ldlm_lock_addref(%s)", ldlm_lockname[mode]); |
| 755 | } |
| 756 | |
| 757 | /** |
| 758 | * Attempts to add reader/writer reference to a lock with handle \a lockh, and |
| 759 | * fails if lock is already LDLM_FL_CBPENDING or destroyed. |
| 760 | * |
| 761 | * \retval 0 success, lock was addref-ed |
| 762 | * |
| 763 | * \retval -EAGAIN lock is being canceled. |
| 764 | */ |
| 765 | int ldlm_lock_addref_try(struct lustre_handle *lockh, __u32 mode) |
| 766 | { |
| 767 | struct ldlm_lock *lock; |
| 768 | int result; |
| 769 | |
| 770 | result = -EAGAIN; |
| 771 | lock = ldlm_handle2lock(lockh); |
| 772 | if (lock != NULL) { |
| 773 | lock_res_and_lock(lock); |
| 774 | if (lock->l_readers != 0 || lock->l_writers != 0 || |
| 775 | !(lock->l_flags & LDLM_FL_CBPENDING)) { |
| 776 | ldlm_lock_addref_internal_nolock(lock, mode); |
| 777 | result = 0; |
| 778 | } |
| 779 | unlock_res_and_lock(lock); |
| 780 | LDLM_LOCK_PUT(lock); |
| 781 | } |
| 782 | return result; |
| 783 | } |
| 784 | EXPORT_SYMBOL(ldlm_lock_addref_try); |
| 785 | |
| 786 | /** |
| 787 | * Add specified reader/writer reference to LDLM lock \a lock. |
| 788 | * Locks LDLM lock and calls ldlm_lock_addref_internal_nolock to do the work. |
| 789 | * Only called for local locks. |
| 790 | */ |
| 791 | void ldlm_lock_addref_internal(struct ldlm_lock *lock, __u32 mode) |
| 792 | { |
| 793 | lock_res_and_lock(lock); |
| 794 | ldlm_lock_addref_internal_nolock(lock, mode); |
| 795 | unlock_res_and_lock(lock); |
| 796 | } |
| 797 | |
| 798 | /** |
| 799 | * Removes reader/writer reference for LDLM lock \a lock. |
| 800 | * Assumes LDLM lock is already locked. |
| 801 | * only called in ldlm_flock_destroy and for local locks. |
| 802 | * Does NOT add lock to LRU if no r/w references left to accomodate flock locks |
| 803 | * that cannot be placed in LRU. |
| 804 | */ |
| 805 | void ldlm_lock_decref_internal_nolock(struct ldlm_lock *lock, __u32 mode) |
| 806 | { |
| 807 | LDLM_DEBUG(lock, "ldlm_lock_decref(%s)", ldlm_lockname[mode]); |
| 808 | if (mode & (LCK_NL | LCK_CR | LCK_PR)) { |
| 809 | LASSERT(lock->l_readers > 0); |
| 810 | lu_ref_del(&lock->l_reference, "reader", lock); |
| 811 | lock->l_readers--; |
| 812 | } |
| 813 | if (mode & (LCK_EX | LCK_CW | LCK_PW | LCK_GROUP | LCK_COS)) { |
| 814 | LASSERT(lock->l_writers > 0); |
| 815 | lu_ref_del(&lock->l_reference, "writer", lock); |
| 816 | lock->l_writers--; |
| 817 | } |
| 818 | |
| 819 | lu_ref_del(&lock->l_reference, "user", lock); |
| 820 | LDLM_LOCK_RELEASE(lock); /* matches the LDLM_LOCK_GET() in addref */ |
| 821 | } |
| 822 | |
| 823 | /** |
| 824 | * Removes reader/writer reference for LDLM lock \a lock. |
| 825 | * Locks LDLM lock first. |
| 826 | * If the lock is determined to be client lock on a client and r/w refcount |
| 827 | * drops to zero and the lock is not blocked, the lock is added to LRU lock |
| 828 | * on the namespace. |
| 829 | * For blocked LDLM locks if r/w count drops to zero, blocking_ast is called. |
| 830 | */ |
| 831 | void ldlm_lock_decref_internal(struct ldlm_lock *lock, __u32 mode) |
| 832 | { |
| 833 | struct ldlm_namespace *ns; |
| 834 | |
| 835 | lock_res_and_lock(lock); |
| 836 | |
| 837 | ns = ldlm_lock_to_ns(lock); |
| 838 | |
| 839 | ldlm_lock_decref_internal_nolock(lock, mode); |
| 840 | |
| 841 | if (lock->l_flags & LDLM_FL_LOCAL && |
| 842 | !lock->l_readers && !lock->l_writers) { |
| 843 | /* If this is a local lock on a server namespace and this was |
| 844 | * the last reference, cancel the lock. */ |
| 845 | CDEBUG(D_INFO, "forcing cancel of local lock\n"); |
| 846 | lock->l_flags |= LDLM_FL_CBPENDING; |
| 847 | } |
| 848 | |
| 849 | if (!lock->l_readers && !lock->l_writers && |
| 850 | (lock->l_flags & LDLM_FL_CBPENDING)) { |
| 851 | /* If we received a blocked AST and this was the last reference, |
| 852 | * run the callback. */ |
| 853 | if ((lock->l_flags & LDLM_FL_NS_SRV) && lock->l_export) |
| 854 | CERROR("FL_CBPENDING set on non-local lock--just a " |
| 855 | "warning\n"); |
| 856 | |
| 857 | LDLM_DEBUG(lock, "final decref done on cbpending lock"); |
| 858 | |
| 859 | LDLM_LOCK_GET(lock); /* dropped by bl thread */ |
| 860 | ldlm_lock_remove_from_lru(lock); |
| 861 | unlock_res_and_lock(lock); |
| 862 | |
| 863 | if (lock->l_flags & LDLM_FL_FAIL_LOC) |
| 864 | OBD_RACE(OBD_FAIL_LDLM_CP_BL_RACE); |
| 865 | |
| 866 | if ((lock->l_flags & LDLM_FL_ATOMIC_CB) || |
| 867 | ldlm_bl_to_thread_lock(ns, NULL, lock) != 0) |
| 868 | ldlm_handle_bl_callback(ns, NULL, lock); |
| 869 | } else if (ns_is_client(ns) && |
| 870 | !lock->l_readers && !lock->l_writers && |
| 871 | !(lock->l_flags & LDLM_FL_NO_LRU) && |
| 872 | !(lock->l_flags & LDLM_FL_BL_AST)) { |
| 873 | |
| 874 | LDLM_DEBUG(lock, "add lock into lru list"); |
| 875 | |
| 876 | /* If this is a client-side namespace and this was the last |
| 877 | * reference, put it on the LRU. */ |
| 878 | ldlm_lock_add_to_lru(lock); |
| 879 | unlock_res_and_lock(lock); |
| 880 | |
| 881 | if (lock->l_flags & LDLM_FL_FAIL_LOC) |
| 882 | OBD_RACE(OBD_FAIL_LDLM_CP_BL_RACE); |
| 883 | |
| 884 | /* Call ldlm_cancel_lru() only if EARLY_CANCEL and LRU RESIZE |
| 885 | * are not supported by the server, otherwise, it is done on |
| 886 | * enqueue. */ |
| 887 | if (!exp_connect_cancelset(lock->l_conn_export) && |
| 888 | !ns_connect_lru_resize(ns)) |
| 889 | ldlm_cancel_lru(ns, 0, LCF_ASYNC, 0); |
| 890 | } else { |
| 891 | LDLM_DEBUG(lock, "do not add lock into lru list"); |
| 892 | unlock_res_and_lock(lock); |
| 893 | } |
| 894 | } |
| 895 | |
| 896 | /** |
| 897 | * Decrease reader/writer refcount for LDLM lock with handle \a lockh |
| 898 | */ |
| 899 | void ldlm_lock_decref(struct lustre_handle *lockh, __u32 mode) |
| 900 | { |
| 901 | struct ldlm_lock *lock = __ldlm_handle2lock(lockh, 0); |
| 902 | LASSERTF(lock != NULL, "Non-existing lock: "LPX64"\n", lockh->cookie); |
| 903 | ldlm_lock_decref_internal(lock, mode); |
| 904 | LDLM_LOCK_PUT(lock); |
| 905 | } |
| 906 | EXPORT_SYMBOL(ldlm_lock_decref); |
| 907 | |
| 908 | /** |
| 909 | * Decrease reader/writer refcount for LDLM lock with handle |
| 910 | * \a lockh and mark it for subsequent cancellation once r/w refcount |
| 911 | * drops to zero instead of putting into LRU. |
| 912 | * |
| 913 | * Typical usage is for GROUP locks which we cannot allow to be cached. |
| 914 | */ |
| 915 | void ldlm_lock_decref_and_cancel(struct lustre_handle *lockh, __u32 mode) |
| 916 | { |
| 917 | struct ldlm_lock *lock = __ldlm_handle2lock(lockh, 0); |
| 918 | |
| 919 | LASSERT(lock != NULL); |
| 920 | |
| 921 | LDLM_DEBUG(lock, "ldlm_lock_decref(%s)", ldlm_lockname[mode]); |
| 922 | lock_res_and_lock(lock); |
| 923 | lock->l_flags |= LDLM_FL_CBPENDING; |
| 924 | unlock_res_and_lock(lock); |
| 925 | ldlm_lock_decref_internal(lock, mode); |
| 926 | LDLM_LOCK_PUT(lock); |
| 927 | } |
| 928 | EXPORT_SYMBOL(ldlm_lock_decref_and_cancel); |
| 929 | |
| 930 | struct sl_insert_point { |
| 931 | struct list_head *res_link; |
| 932 | struct list_head *mode_link; |
| 933 | struct list_head *policy_link; |
| 934 | }; |
| 935 | |
| 936 | /** |
| 937 | * Finds a position to insert the new lock into granted lock list. |
| 938 | * |
| 939 | * Used for locks eligible for skiplist optimization. |
| 940 | * |
| 941 | * Parameters: |
| 942 | * queue [input]: the granted list where search acts on; |
| 943 | * req [input]: the lock whose position to be located; |
| 944 | * prev [output]: positions within 3 lists to insert @req to |
| 945 | * Return Value: |
| 946 | * filled @prev |
| 947 | * NOTE: called by |
| 948 | * - ldlm_grant_lock_with_skiplist |
| 949 | */ |
| 950 | static void search_granted_lock(struct list_head *queue, |
| 951 | struct ldlm_lock *req, |
| 952 | struct sl_insert_point *prev) |
| 953 | { |
| 954 | struct list_head *tmp; |
| 955 | struct ldlm_lock *lock, *mode_end, *policy_end; |
| 956 | |
| 957 | list_for_each(tmp, queue) { |
| 958 | lock = list_entry(tmp, struct ldlm_lock, l_res_link); |
| 959 | |
| 960 | mode_end = list_entry(lock->l_sl_mode.prev, |
| 961 | struct ldlm_lock, l_sl_mode); |
| 962 | |
| 963 | if (lock->l_req_mode != req->l_req_mode) { |
| 964 | /* jump to last lock of mode group */ |
| 965 | tmp = &mode_end->l_res_link; |
| 966 | continue; |
| 967 | } |
| 968 | |
| 969 | /* suitable mode group is found */ |
| 970 | if (lock->l_resource->lr_type == LDLM_PLAIN) { |
| 971 | /* insert point is last lock of the mode group */ |
| 972 | prev->res_link = &mode_end->l_res_link; |
| 973 | prev->mode_link = &mode_end->l_sl_mode; |
| 974 | prev->policy_link = &req->l_sl_policy; |
| 975 | return; |
| 976 | } else if (lock->l_resource->lr_type == LDLM_IBITS) { |
| 977 | for (;;) { |
| 978 | policy_end = |
| 979 | list_entry(lock->l_sl_policy.prev, |
| 980 | struct ldlm_lock, |
| 981 | l_sl_policy); |
| 982 | |
| 983 | if (lock->l_policy_data.l_inodebits.bits == |
| 984 | req->l_policy_data.l_inodebits.bits) { |
| 985 | /* insert point is last lock of |
| 986 | * the policy group */ |
| 987 | prev->res_link = |
| 988 | &policy_end->l_res_link; |
| 989 | prev->mode_link = |
| 990 | &policy_end->l_sl_mode; |
| 991 | prev->policy_link = |
| 992 | &policy_end->l_sl_policy; |
| 993 | return; |
| 994 | } |
| 995 | |
| 996 | if (policy_end == mode_end) |
| 997 | /* done with mode group */ |
| 998 | break; |
| 999 | |
| 1000 | /* go to next policy group within mode group */ |
| 1001 | tmp = policy_end->l_res_link.next; |
| 1002 | lock = list_entry(tmp, struct ldlm_lock, |
| 1003 | l_res_link); |
| 1004 | } /* loop over policy groups within the mode group */ |
| 1005 | |
| 1006 | /* insert point is last lock of the mode group, |
| 1007 | * new policy group is started */ |
| 1008 | prev->res_link = &mode_end->l_res_link; |
| 1009 | prev->mode_link = &mode_end->l_sl_mode; |
| 1010 | prev->policy_link = &req->l_sl_policy; |
| 1011 | return; |
| 1012 | } else { |
| 1013 | LDLM_ERROR(lock,"is not LDLM_PLAIN or LDLM_IBITS lock"); |
| 1014 | LBUG(); |
| 1015 | } |
| 1016 | } |
| 1017 | |
| 1018 | /* insert point is last lock on the queue, |
| 1019 | * new mode group and new policy group are started */ |
| 1020 | prev->res_link = queue->prev; |
| 1021 | prev->mode_link = &req->l_sl_mode; |
| 1022 | prev->policy_link = &req->l_sl_policy; |
| 1023 | return; |
| 1024 | } |
| 1025 | |
| 1026 | /** |
| 1027 | * Add a lock into resource granted list after a position described by |
| 1028 | * \a prev. |
| 1029 | */ |
| 1030 | static void ldlm_granted_list_add_lock(struct ldlm_lock *lock, |
| 1031 | struct sl_insert_point *prev) |
| 1032 | { |
| 1033 | struct ldlm_resource *res = lock->l_resource; |
| 1034 | |
| 1035 | check_res_locked(res); |
| 1036 | |
| 1037 | ldlm_resource_dump(D_INFO, res); |
| 1038 | LDLM_DEBUG(lock, "About to add lock:"); |
| 1039 | |
| 1040 | if (lock->l_flags & LDLM_FL_DESTROYED) { |
| 1041 | CDEBUG(D_OTHER, "Lock destroyed, not adding to resource\n"); |
| 1042 | return; |
| 1043 | } |
| 1044 | |
| 1045 | LASSERT(list_empty(&lock->l_res_link)); |
| 1046 | LASSERT(list_empty(&lock->l_sl_mode)); |
| 1047 | LASSERT(list_empty(&lock->l_sl_policy)); |
| 1048 | |
| 1049 | /* |
| 1050 | * lock->link == prev->link means lock is first starting the group. |
| 1051 | * Don't re-add to itself to suppress kernel warnings. |
| 1052 | */ |
| 1053 | if (&lock->l_res_link != prev->res_link) |
| 1054 | list_add(&lock->l_res_link, prev->res_link); |
| 1055 | if (&lock->l_sl_mode != prev->mode_link) |
| 1056 | list_add(&lock->l_sl_mode, prev->mode_link); |
| 1057 | if (&lock->l_sl_policy != prev->policy_link) |
| 1058 | list_add(&lock->l_sl_policy, prev->policy_link); |
| 1059 | } |
| 1060 | |
| 1061 | /** |
| 1062 | * Add a lock to granted list on a resource maintaining skiplist |
| 1063 | * correctness. |
| 1064 | */ |
| 1065 | static void ldlm_grant_lock_with_skiplist(struct ldlm_lock *lock) |
| 1066 | { |
| 1067 | struct sl_insert_point prev; |
| 1068 | |
| 1069 | LASSERT(lock->l_req_mode == lock->l_granted_mode); |
| 1070 | |
| 1071 | search_granted_lock(&lock->l_resource->lr_granted, lock, &prev); |
| 1072 | ldlm_granted_list_add_lock(lock, &prev); |
| 1073 | } |
| 1074 | |
| 1075 | /** |
| 1076 | * Perform lock granting bookkeeping. |
| 1077 | * |
| 1078 | * Includes putting the lock into granted list and updating lock mode. |
| 1079 | * NOTE: called by |
| 1080 | * - ldlm_lock_enqueue |
| 1081 | * - ldlm_reprocess_queue |
| 1082 | * - ldlm_lock_convert |
| 1083 | * |
| 1084 | * must be called with lr_lock held |
| 1085 | */ |
| 1086 | void ldlm_grant_lock(struct ldlm_lock *lock, struct list_head *work_list) |
| 1087 | { |
| 1088 | struct ldlm_resource *res = lock->l_resource; |
| 1089 | |
| 1090 | check_res_locked(res); |
| 1091 | |
| 1092 | lock->l_granted_mode = lock->l_req_mode; |
| 1093 | if (res->lr_type == LDLM_PLAIN || res->lr_type == LDLM_IBITS) |
| 1094 | ldlm_grant_lock_with_skiplist(lock); |
| 1095 | else if (res->lr_type == LDLM_EXTENT) |
| 1096 | ldlm_extent_add_lock(res, lock); |
| 1097 | else |
| 1098 | ldlm_resource_add_lock(res, &res->lr_granted, lock); |
| 1099 | |
| 1100 | if (lock->l_granted_mode < res->lr_most_restr) |
| 1101 | res->lr_most_restr = lock->l_granted_mode; |
| 1102 | |
| 1103 | if (work_list && lock->l_completion_ast != NULL) |
| 1104 | ldlm_add_ast_work_item(lock, NULL, work_list); |
| 1105 | |
| 1106 | ldlm_pool_add(&ldlm_res_to_ns(res)->ns_pool, lock); |
| 1107 | } |
| 1108 | |
| 1109 | /** |
| 1110 | * Search for a lock with given properties in a queue. |
| 1111 | * |
| 1112 | * \retval a referenced lock or NULL. See the flag descriptions below, in the |
| 1113 | * comment above ldlm_lock_match |
| 1114 | */ |
| 1115 | static struct ldlm_lock *search_queue(struct list_head *queue, |
| 1116 | ldlm_mode_t *mode, |
| 1117 | ldlm_policy_data_t *policy, |
| 1118 | struct ldlm_lock *old_lock, |
| 1119 | __u64 flags, int unref) |
| 1120 | { |
| 1121 | struct ldlm_lock *lock; |
| 1122 | struct list_head *tmp; |
| 1123 | |
| 1124 | list_for_each(tmp, queue) { |
| 1125 | ldlm_mode_t match; |
| 1126 | |
| 1127 | lock = list_entry(tmp, struct ldlm_lock, l_res_link); |
| 1128 | |
| 1129 | if (lock == old_lock) |
| 1130 | break; |
| 1131 | |
| 1132 | /* llite sometimes wants to match locks that will be |
| 1133 | * canceled when their users drop, but we allow it to match |
| 1134 | * if it passes in CBPENDING and the lock still has users. |
| 1135 | * this is generally only going to be used by children |
| 1136 | * whose parents already hold a lock so forward progress |
| 1137 | * can still happen. */ |
| 1138 | if (lock->l_flags & LDLM_FL_CBPENDING && |
| 1139 | !(flags & LDLM_FL_CBPENDING)) |
| 1140 | continue; |
| 1141 | if (!unref && lock->l_flags & LDLM_FL_CBPENDING && |
| 1142 | lock->l_readers == 0 && lock->l_writers == 0) |
| 1143 | continue; |
| 1144 | |
| 1145 | if (!(lock->l_req_mode & *mode)) |
| 1146 | continue; |
| 1147 | match = lock->l_req_mode; |
| 1148 | |
| 1149 | if (lock->l_resource->lr_type == LDLM_EXTENT && |
| 1150 | (lock->l_policy_data.l_extent.start > |
| 1151 | policy->l_extent.start || |
| 1152 | lock->l_policy_data.l_extent.end < policy->l_extent.end)) |
| 1153 | continue; |
| 1154 | |
| 1155 | if (unlikely(match == LCK_GROUP) && |
| 1156 | lock->l_resource->lr_type == LDLM_EXTENT && |
| 1157 | lock->l_policy_data.l_extent.gid != policy->l_extent.gid) |
| 1158 | continue; |
| 1159 | |
| 1160 | /* We match if we have existing lock with same or wider set |
| 1161 | of bits. */ |
| 1162 | if (lock->l_resource->lr_type == LDLM_IBITS && |
| 1163 | ((lock->l_policy_data.l_inodebits.bits & |
| 1164 | policy->l_inodebits.bits) != |
| 1165 | policy->l_inodebits.bits)) |
| 1166 | continue; |
| 1167 | |
| 1168 | if (!unref && (lock->l_flags & LDLM_FL_GONE_MASK)) |
| 1169 | continue; |
| 1170 | |
| 1171 | if ((flags & LDLM_FL_LOCAL_ONLY) && |
| 1172 | !(lock->l_flags & LDLM_FL_LOCAL)) |
| 1173 | continue; |
| 1174 | |
| 1175 | if (flags & LDLM_FL_TEST_LOCK) { |
| 1176 | LDLM_LOCK_GET(lock); |
| 1177 | ldlm_lock_touch_in_lru(lock); |
| 1178 | } else { |
| 1179 | ldlm_lock_addref_internal_nolock(lock, match); |
| 1180 | } |
| 1181 | *mode = match; |
| 1182 | return lock; |
| 1183 | } |
| 1184 | |
| 1185 | return NULL; |
| 1186 | } |
| 1187 | |
| 1188 | void ldlm_lock_fail_match_locked(struct ldlm_lock *lock) |
| 1189 | { |
| 1190 | if ((lock->l_flags & LDLM_FL_FAIL_NOTIFIED) == 0) { |
| 1191 | lock->l_flags |= LDLM_FL_FAIL_NOTIFIED; |
| 1192 | wake_up_all(&lock->l_waitq); |
| 1193 | } |
| 1194 | } |
| 1195 | EXPORT_SYMBOL(ldlm_lock_fail_match_locked); |
| 1196 | |
| 1197 | void ldlm_lock_fail_match(struct ldlm_lock *lock) |
| 1198 | { |
| 1199 | lock_res_and_lock(lock); |
| 1200 | ldlm_lock_fail_match_locked(lock); |
| 1201 | unlock_res_and_lock(lock); |
| 1202 | } |
| 1203 | EXPORT_SYMBOL(ldlm_lock_fail_match); |
| 1204 | |
| 1205 | /** |
| 1206 | * Mark lock as "matchable" by OST. |
| 1207 | * |
| 1208 | * Used to prevent certain races in LOV/OSC where the lock is granted, but LVB |
| 1209 | * is not yet valid. |
| 1210 | * Assumes LDLM lock is already locked. |
| 1211 | */ |
| 1212 | void ldlm_lock_allow_match_locked(struct ldlm_lock *lock) |
| 1213 | { |
| 1214 | lock->l_flags |= LDLM_FL_LVB_READY; |
| 1215 | wake_up_all(&lock->l_waitq); |
| 1216 | } |
| 1217 | EXPORT_SYMBOL(ldlm_lock_allow_match_locked); |
| 1218 | |
| 1219 | /** |
| 1220 | * Mark lock as "matchable" by OST. |
| 1221 | * Locks the lock and then \see ldlm_lock_allow_match_locked |
| 1222 | */ |
| 1223 | void ldlm_lock_allow_match(struct ldlm_lock *lock) |
| 1224 | { |
| 1225 | lock_res_and_lock(lock); |
| 1226 | ldlm_lock_allow_match_locked(lock); |
| 1227 | unlock_res_and_lock(lock); |
| 1228 | } |
| 1229 | EXPORT_SYMBOL(ldlm_lock_allow_match); |
| 1230 | |
| 1231 | /** |
| 1232 | * Attempt to find a lock with specified properties. |
| 1233 | * |
| 1234 | * Typically returns a reference to matched lock unless LDLM_FL_TEST_LOCK is |
| 1235 | * set in \a flags |
| 1236 | * |
| 1237 | * Can be called in two ways: |
| 1238 | * |
| 1239 | * If 'ns' is NULL, then lockh describes an existing lock that we want to look |
| 1240 | * for a duplicate of. |
| 1241 | * |
| 1242 | * Otherwise, all of the fields must be filled in, to match against. |
| 1243 | * |
| 1244 | * If 'flags' contains LDLM_FL_LOCAL_ONLY, then only match local locks on the |
| 1245 | * server (ie, connh is NULL) |
| 1246 | * If 'flags' contains LDLM_FL_BLOCK_GRANTED, then only locks on the granted |
| 1247 | * list will be considered |
| 1248 | * If 'flags' contains LDLM_FL_CBPENDING, then locks that have been marked |
| 1249 | * to be canceled can still be matched as long as they still have reader |
| 1250 | * or writer refernces |
| 1251 | * If 'flags' contains LDLM_FL_TEST_LOCK, then don't actually reference a lock, |
| 1252 | * just tell us if we would have matched. |
| 1253 | * |
| 1254 | * \retval 1 if it finds an already-existing lock that is compatible; in this |
| 1255 | * case, lockh is filled in with a addref()ed lock |
| 1256 | * |
| 1257 | * We also check security context, and if that fails we simply return 0 (to |
| 1258 | * keep caller code unchanged), the context failure will be discovered by |
| 1259 | * caller sometime later. |
| 1260 | */ |
| 1261 | ldlm_mode_t ldlm_lock_match(struct ldlm_namespace *ns, __u64 flags, |
| 1262 | const struct ldlm_res_id *res_id, ldlm_type_t type, |
| 1263 | ldlm_policy_data_t *policy, ldlm_mode_t mode, |
| 1264 | struct lustre_handle *lockh, int unref) |
| 1265 | { |
| 1266 | struct ldlm_resource *res; |
| 1267 | struct ldlm_lock *lock, *old_lock = NULL; |
| 1268 | int rc = 0; |
| 1269 | |
| 1270 | if (ns == NULL) { |
| 1271 | old_lock = ldlm_handle2lock(lockh); |
| 1272 | LASSERT(old_lock); |
| 1273 | |
| 1274 | ns = ldlm_lock_to_ns(old_lock); |
| 1275 | res_id = &old_lock->l_resource->lr_name; |
| 1276 | type = old_lock->l_resource->lr_type; |
| 1277 | mode = old_lock->l_req_mode; |
| 1278 | } |
| 1279 | |
| 1280 | res = ldlm_resource_get(ns, NULL, res_id, type, 0); |
| 1281 | if (res == NULL) { |
| 1282 | LASSERT(old_lock == NULL); |
| 1283 | return 0; |
| 1284 | } |
| 1285 | |
| 1286 | LDLM_RESOURCE_ADDREF(res); |
| 1287 | lock_res(res); |
| 1288 | |
| 1289 | lock = search_queue(&res->lr_granted, &mode, policy, old_lock, |
| 1290 | flags, unref); |
| 1291 | if (lock != NULL) |
| 1292 | GOTO(out, rc = 1); |
| 1293 | if (flags & LDLM_FL_BLOCK_GRANTED) |
| 1294 | GOTO(out, rc = 0); |
| 1295 | lock = search_queue(&res->lr_converting, &mode, policy, old_lock, |
| 1296 | flags, unref); |
| 1297 | if (lock != NULL) |
| 1298 | GOTO(out, rc = 1); |
| 1299 | lock = search_queue(&res->lr_waiting, &mode, policy, old_lock, |
| 1300 | flags, unref); |
| 1301 | if (lock != NULL) |
| 1302 | GOTO(out, rc = 1); |
| 1303 | |
| 1304 | out: |
| 1305 | unlock_res(res); |
| 1306 | LDLM_RESOURCE_DELREF(res); |
| 1307 | ldlm_resource_putref(res); |
| 1308 | |
| 1309 | if (lock) { |
| 1310 | ldlm_lock2handle(lock, lockh); |
| 1311 | if ((flags & LDLM_FL_LVB_READY) && |
| 1312 | (!(lock->l_flags & LDLM_FL_LVB_READY))) { |
| 1313 | __u64 wait_flags = LDLM_FL_LVB_READY | |
| 1314 | LDLM_FL_DESTROYED | LDLM_FL_FAIL_NOTIFIED; |
| 1315 | struct l_wait_info lwi; |
| 1316 | if (lock->l_completion_ast) { |
| 1317 | int err = lock->l_completion_ast(lock, |
| 1318 | LDLM_FL_WAIT_NOREPROC, |
| 1319 | NULL); |
| 1320 | if (err) { |
| 1321 | if (flags & LDLM_FL_TEST_LOCK) |
| 1322 | LDLM_LOCK_RELEASE(lock); |
| 1323 | else |
| 1324 | ldlm_lock_decref_internal(lock, |
| 1325 | mode); |
| 1326 | rc = 0; |
| 1327 | goto out2; |
| 1328 | } |
| 1329 | } |
| 1330 | |
| 1331 | lwi = LWI_TIMEOUT_INTR(cfs_time_seconds(obd_timeout), |
| 1332 | NULL, LWI_ON_SIGNAL_NOOP, NULL); |
| 1333 | |
| 1334 | /* XXX FIXME see comment on CAN_MATCH in lustre_dlm.h */ |
| 1335 | l_wait_event(lock->l_waitq, |
| 1336 | lock->l_flags & wait_flags, |
| 1337 | &lwi); |
| 1338 | if (!(lock->l_flags & LDLM_FL_LVB_READY)) { |
| 1339 | if (flags & LDLM_FL_TEST_LOCK) |
| 1340 | LDLM_LOCK_RELEASE(lock); |
| 1341 | else |
| 1342 | ldlm_lock_decref_internal(lock, mode); |
| 1343 | rc = 0; |
| 1344 | } |
| 1345 | } |
| 1346 | } |
| 1347 | out2: |
| 1348 | if (rc) { |
| 1349 | LDLM_DEBUG(lock, "matched ("LPU64" "LPU64")", |
| 1350 | (type == LDLM_PLAIN || type == LDLM_IBITS) ? |
| 1351 | res_id->name[2] : policy->l_extent.start, |
| 1352 | (type == LDLM_PLAIN || type == LDLM_IBITS) ? |
| 1353 | res_id->name[3] : policy->l_extent.end); |
| 1354 | |
| 1355 | /* check user's security context */ |
| 1356 | if (lock->l_conn_export && |
| 1357 | sptlrpc_import_check_ctx( |
| 1358 | class_exp2cliimp(lock->l_conn_export))) { |
| 1359 | if (!(flags & LDLM_FL_TEST_LOCK)) |
| 1360 | ldlm_lock_decref_internal(lock, mode); |
| 1361 | rc = 0; |
| 1362 | } |
| 1363 | |
| 1364 | if (flags & LDLM_FL_TEST_LOCK) |
| 1365 | LDLM_LOCK_RELEASE(lock); |
| 1366 | |
| 1367 | } else if (!(flags & LDLM_FL_TEST_LOCK)) {/*less verbose for test-only*/ |
| 1368 | LDLM_DEBUG_NOLOCK("not matched ns %p type %u mode %u res " |
| 1369 | LPU64"/"LPU64" ("LPU64" "LPU64")", ns, |
| 1370 | type, mode, res_id->name[0], res_id->name[1], |
| 1371 | (type == LDLM_PLAIN || type == LDLM_IBITS) ? |
| 1372 | res_id->name[2] :policy->l_extent.start, |
| 1373 | (type == LDLM_PLAIN || type == LDLM_IBITS) ? |
| 1374 | res_id->name[3] : policy->l_extent.end); |
| 1375 | } |
| 1376 | if (old_lock) |
| 1377 | LDLM_LOCK_PUT(old_lock); |
| 1378 | |
| 1379 | return rc ? mode : 0; |
| 1380 | } |
| 1381 | EXPORT_SYMBOL(ldlm_lock_match); |
| 1382 | |
| 1383 | ldlm_mode_t ldlm_revalidate_lock_handle(struct lustre_handle *lockh, |
| 1384 | __u64 *bits) |
| 1385 | { |
| 1386 | struct ldlm_lock *lock; |
| 1387 | ldlm_mode_t mode = 0; |
| 1388 | |
| 1389 | lock = ldlm_handle2lock(lockh); |
| 1390 | if (lock != NULL) { |
| 1391 | lock_res_and_lock(lock); |
| 1392 | if (lock->l_flags & LDLM_FL_GONE_MASK) |
| 1393 | GOTO(out, mode); |
| 1394 | |
| 1395 | if (lock->l_flags & LDLM_FL_CBPENDING && |
| 1396 | lock->l_readers == 0 && lock->l_writers == 0) |
| 1397 | GOTO(out, mode); |
| 1398 | |
| 1399 | if (bits) |
| 1400 | *bits = lock->l_policy_data.l_inodebits.bits; |
| 1401 | mode = lock->l_granted_mode; |
| 1402 | ldlm_lock_addref_internal_nolock(lock, mode); |
| 1403 | } |
| 1404 | |
| 1405 | out: |
| 1406 | if (lock != NULL) { |
| 1407 | unlock_res_and_lock(lock); |
| 1408 | LDLM_LOCK_PUT(lock); |
| 1409 | } |
| 1410 | return mode; |
| 1411 | } |
| 1412 | EXPORT_SYMBOL(ldlm_revalidate_lock_handle); |
| 1413 | |
| 1414 | /** The caller must guarantee that the buffer is large enough. */ |
| 1415 | int ldlm_fill_lvb(struct ldlm_lock *lock, struct req_capsule *pill, |
| 1416 | enum req_location loc, void *data, int size) |
| 1417 | { |
| 1418 | void *lvb; |
| 1419 | |
| 1420 | LASSERT(data != NULL); |
| 1421 | LASSERT(size >= 0); |
| 1422 | |
| 1423 | switch (lock->l_lvb_type) { |
| 1424 | case LVB_T_OST: |
| 1425 | if (size == sizeof(struct ost_lvb)) { |
| 1426 | if (loc == RCL_CLIENT) |
| 1427 | lvb = req_capsule_client_swab_get(pill, |
| 1428 | &RMF_DLM_LVB, |
| 1429 | lustre_swab_ost_lvb); |
| 1430 | else |
| 1431 | lvb = req_capsule_server_swab_get(pill, |
| 1432 | &RMF_DLM_LVB, |
| 1433 | lustre_swab_ost_lvb); |
| 1434 | if (unlikely(lvb == NULL)) { |
| 1435 | LDLM_ERROR(lock, "no LVB"); |
| 1436 | return -EPROTO; |
| 1437 | } |
| 1438 | |
| 1439 | memcpy(data, lvb, size); |
| 1440 | } else if (size == sizeof(struct ost_lvb_v1)) { |
| 1441 | struct ost_lvb *olvb = data; |
| 1442 | |
| 1443 | if (loc == RCL_CLIENT) |
| 1444 | lvb = req_capsule_client_swab_get(pill, |
| 1445 | &RMF_DLM_LVB, |
| 1446 | lustre_swab_ost_lvb_v1); |
| 1447 | else |
| 1448 | lvb = req_capsule_server_sized_swab_get(pill, |
| 1449 | &RMF_DLM_LVB, size, |
| 1450 | lustre_swab_ost_lvb_v1); |
| 1451 | if (unlikely(lvb == NULL)) { |
| 1452 | LDLM_ERROR(lock, "no LVB"); |
| 1453 | return -EPROTO; |
| 1454 | } |
| 1455 | |
| 1456 | memcpy(data, lvb, size); |
| 1457 | olvb->lvb_mtime_ns = 0; |
| 1458 | olvb->lvb_atime_ns = 0; |
| 1459 | olvb->lvb_ctime_ns = 0; |
| 1460 | } else { |
| 1461 | LDLM_ERROR(lock, "Replied unexpected ost LVB size %d", |
| 1462 | size); |
| 1463 | return -EINVAL; |
| 1464 | } |
| 1465 | break; |
| 1466 | case LVB_T_LQUOTA: |
| 1467 | if (size == sizeof(struct lquota_lvb)) { |
| 1468 | if (loc == RCL_CLIENT) |
| 1469 | lvb = req_capsule_client_swab_get(pill, |
| 1470 | &RMF_DLM_LVB, |
| 1471 | lustre_swab_lquota_lvb); |
| 1472 | else |
| 1473 | lvb = req_capsule_server_swab_get(pill, |
| 1474 | &RMF_DLM_LVB, |
| 1475 | lustre_swab_lquota_lvb); |
| 1476 | if (unlikely(lvb == NULL)) { |
| 1477 | LDLM_ERROR(lock, "no LVB"); |
| 1478 | return -EPROTO; |
| 1479 | } |
| 1480 | |
| 1481 | memcpy(data, lvb, size); |
| 1482 | } else { |
| 1483 | LDLM_ERROR(lock, "Replied unexpected lquota LVB size %d", |
| 1484 | size); |
| 1485 | return -EINVAL; |
| 1486 | } |
| 1487 | break; |
| 1488 | case LVB_T_LAYOUT: |
| 1489 | if (size == 0) |
| 1490 | break; |
| 1491 | |
| 1492 | if (loc == RCL_CLIENT) |
| 1493 | lvb = req_capsule_client_get(pill, &RMF_DLM_LVB); |
| 1494 | else |
| 1495 | lvb = req_capsule_server_get(pill, &RMF_DLM_LVB); |
| 1496 | if (unlikely(lvb == NULL)) { |
| 1497 | LDLM_ERROR(lock, "no LVB"); |
| 1498 | return -EPROTO; |
| 1499 | } |
| 1500 | |
| 1501 | memcpy(data, lvb, size); |
| 1502 | break; |
| 1503 | default: |
| 1504 | LDLM_ERROR(lock, "Unknown LVB type: %d\n", lock->l_lvb_type); |
| 1505 | dump_stack(); |
| 1506 | return -EINVAL; |
| 1507 | } |
| 1508 | |
| 1509 | return 0; |
| 1510 | } |
| 1511 | |
| 1512 | /** |
| 1513 | * Create and fill in new LDLM lock with specified properties. |
| 1514 | * Returns a referenced lock |
| 1515 | */ |
| 1516 | struct ldlm_lock *ldlm_lock_create(struct ldlm_namespace *ns, |
| 1517 | const struct ldlm_res_id *res_id, |
| 1518 | ldlm_type_t type, |
| 1519 | ldlm_mode_t mode, |
| 1520 | const struct ldlm_callback_suite *cbs, |
| 1521 | void *data, __u32 lvb_len, |
| 1522 | enum lvb_type lvb_type) |
| 1523 | { |
| 1524 | struct ldlm_lock *lock; |
| 1525 | struct ldlm_resource *res; |
| 1526 | |
| 1527 | res = ldlm_resource_get(ns, NULL, res_id, type, 1); |
| 1528 | if (res == NULL) |
| 1529 | return NULL; |
| 1530 | |
| 1531 | lock = ldlm_lock_new(res); |
| 1532 | |
| 1533 | if (lock == NULL) |
| 1534 | return NULL; |
| 1535 | |
| 1536 | lock->l_req_mode = mode; |
| 1537 | lock->l_ast_data = data; |
| 1538 | lock->l_pid = current_pid(); |
| 1539 | if (ns_is_server(ns)) |
| 1540 | lock->l_flags |= LDLM_FL_NS_SRV; |
| 1541 | if (cbs) { |
| 1542 | lock->l_blocking_ast = cbs->lcs_blocking; |
| 1543 | lock->l_completion_ast = cbs->lcs_completion; |
| 1544 | lock->l_glimpse_ast = cbs->lcs_glimpse; |
| 1545 | } |
| 1546 | |
| 1547 | lock->l_tree_node = NULL; |
| 1548 | /* if this is the extent lock, allocate the interval tree node */ |
| 1549 | if (type == LDLM_EXTENT) { |
| 1550 | if (ldlm_interval_alloc(lock) == NULL) |
| 1551 | GOTO(out, 0); |
| 1552 | } |
| 1553 | |
| 1554 | if (lvb_len) { |
| 1555 | lock->l_lvb_len = lvb_len; |
| 1556 | OBD_ALLOC(lock->l_lvb_data, lvb_len); |
| 1557 | if (lock->l_lvb_data == NULL) |
| 1558 | GOTO(out, 0); |
| 1559 | } |
| 1560 | |
| 1561 | lock->l_lvb_type = lvb_type; |
| 1562 | if (OBD_FAIL_CHECK(OBD_FAIL_LDLM_NEW_LOCK)) |
| 1563 | GOTO(out, 0); |
| 1564 | |
| 1565 | return lock; |
| 1566 | |
| 1567 | out: |
| 1568 | ldlm_lock_destroy(lock); |
| 1569 | LDLM_LOCK_RELEASE(lock); |
| 1570 | return NULL; |
| 1571 | } |
| 1572 | |
| 1573 | /** |
| 1574 | * Enqueue (request) a lock. |
| 1575 | * |
| 1576 | * Does not block. As a result of enqueue the lock would be put |
| 1577 | * into granted or waiting list. |
| 1578 | * |
| 1579 | * If namespace has intent policy sent and the lock has LDLM_FL_HAS_INTENT flag |
| 1580 | * set, skip all the enqueueing and delegate lock processing to intent policy |
| 1581 | * function. |
| 1582 | */ |
| 1583 | ldlm_error_t ldlm_lock_enqueue(struct ldlm_namespace *ns, |
| 1584 | struct ldlm_lock **lockp, |
| 1585 | void *cookie, __u64 *flags) |
| 1586 | { |
| 1587 | struct ldlm_lock *lock = *lockp; |
| 1588 | struct ldlm_resource *res = lock->l_resource; |
| 1589 | int local = ns_is_client(ldlm_res_to_ns(res)); |
| 1590 | ldlm_error_t rc = ELDLM_OK; |
| 1591 | struct ldlm_interval *node = NULL; |
| 1592 | |
| 1593 | lock->l_last_activity = cfs_time_current_sec(); |
| 1594 | /* policies are not executed on the client or during replay */ |
| 1595 | if ((*flags & (LDLM_FL_HAS_INTENT|LDLM_FL_REPLAY)) == LDLM_FL_HAS_INTENT |
| 1596 | && !local && ns->ns_policy) { |
| 1597 | rc = ns->ns_policy(ns, lockp, cookie, lock->l_req_mode, *flags, |
| 1598 | NULL); |
| 1599 | if (rc == ELDLM_LOCK_REPLACED) { |
| 1600 | /* The lock that was returned has already been granted, |
| 1601 | * and placed into lockp. If it's not the same as the |
| 1602 | * one we passed in, then destroy the old one and our |
| 1603 | * work here is done. */ |
| 1604 | if (lock != *lockp) { |
| 1605 | ldlm_lock_destroy(lock); |
| 1606 | LDLM_LOCK_RELEASE(lock); |
| 1607 | } |
| 1608 | *flags |= LDLM_FL_LOCK_CHANGED; |
| 1609 | return 0; |
| 1610 | } else if (rc != ELDLM_OK || |
| 1611 | (rc == ELDLM_OK && (*flags & LDLM_FL_INTENT_ONLY))) { |
| 1612 | ldlm_lock_destroy(lock); |
| 1613 | return rc; |
| 1614 | } |
| 1615 | } |
| 1616 | |
| 1617 | /* For a replaying lock, it might be already in granted list. So |
| 1618 | * unlinking the lock will cause the interval node to be freed, we |
| 1619 | * have to allocate the interval node early otherwise we can't regrant |
| 1620 | * this lock in the future. - jay */ |
| 1621 | if (!local && (*flags & LDLM_FL_REPLAY) && res->lr_type == LDLM_EXTENT) |
| 1622 | OBD_SLAB_ALLOC_PTR_GFP(node, ldlm_interval_slab, __GFP_IO); |
| 1623 | |
| 1624 | lock_res_and_lock(lock); |
| 1625 | if (local && lock->l_req_mode == lock->l_granted_mode) { |
| 1626 | /* The server returned a blocked lock, but it was granted |
| 1627 | * before we got a chance to actually enqueue it. We don't |
| 1628 | * need to do anything else. */ |
| 1629 | *flags &= ~(LDLM_FL_BLOCK_GRANTED | |
| 1630 | LDLM_FL_BLOCK_CONV | LDLM_FL_BLOCK_WAIT); |
| 1631 | GOTO(out, ELDLM_OK); |
| 1632 | } |
| 1633 | |
| 1634 | ldlm_resource_unlink_lock(lock); |
| 1635 | if (res->lr_type == LDLM_EXTENT && lock->l_tree_node == NULL) { |
| 1636 | if (node == NULL) { |
| 1637 | ldlm_lock_destroy_nolock(lock); |
| 1638 | GOTO(out, rc = -ENOMEM); |
| 1639 | } |
| 1640 | |
| 1641 | INIT_LIST_HEAD(&node->li_group); |
| 1642 | ldlm_interval_attach(node, lock); |
| 1643 | node = NULL; |
| 1644 | } |
| 1645 | |
| 1646 | /* Some flags from the enqueue want to make it into the AST, via the |
| 1647 | * lock's l_flags. */ |
| 1648 | lock->l_flags |= *flags & LDLM_FL_AST_DISCARD_DATA; |
| 1649 | |
| 1650 | /* This distinction between local lock trees is very important; a client |
| 1651 | * namespace only has information about locks taken by that client, and |
| 1652 | * thus doesn't have enough information to decide for itself if it can |
| 1653 | * be granted (below). In this case, we do exactly what the server |
| 1654 | * tells us to do, as dictated by the 'flags'. |
| 1655 | * |
| 1656 | * We do exactly the same thing during recovery, when the server is |
| 1657 | * more or less trusting the clients not to lie. |
| 1658 | * |
| 1659 | * FIXME (bug 268): Detect obvious lies by checking compatibility in |
| 1660 | * granted/converting queues. */ |
| 1661 | if (local) { |
| 1662 | if (*flags & LDLM_FL_BLOCK_CONV) |
| 1663 | ldlm_resource_add_lock(res, &res->lr_converting, lock); |
| 1664 | else if (*flags & (LDLM_FL_BLOCK_WAIT | LDLM_FL_BLOCK_GRANTED)) |
| 1665 | ldlm_resource_add_lock(res, &res->lr_waiting, lock); |
| 1666 | else |
| 1667 | ldlm_grant_lock(lock, NULL); |
| 1668 | GOTO(out, ELDLM_OK); |
| 1669 | } else { |
| 1670 | CERROR("This is client-side-only module, cannot handle " |
| 1671 | "LDLM_NAMESPACE_SERVER resource type lock.\n"); |
| 1672 | LBUG(); |
| 1673 | } |
| 1674 | |
| 1675 | out: |
| 1676 | unlock_res_and_lock(lock); |
| 1677 | if (node) |
| 1678 | OBD_SLAB_FREE(node, ldlm_interval_slab, sizeof(*node)); |
| 1679 | return rc; |
| 1680 | } |
| 1681 | |
| 1682 | |
| 1683 | /** |
| 1684 | * Process a call to blocking AST callback for a lock in ast_work list |
| 1685 | */ |
| 1686 | static int |
| 1687 | ldlm_work_bl_ast_lock(struct ptlrpc_request_set *rqset, void *opaq) |
| 1688 | { |
| 1689 | struct ldlm_cb_set_arg *arg = opaq; |
| 1690 | struct ldlm_lock_desc d; |
| 1691 | int rc; |
| 1692 | struct ldlm_lock *lock; |
| 1693 | |
| 1694 | if (list_empty(arg->list)) |
| 1695 | return -ENOENT; |
| 1696 | |
| 1697 | lock = list_entry(arg->list->next, struct ldlm_lock, l_bl_ast); |
| 1698 | |
| 1699 | /* nobody should touch l_bl_ast */ |
| 1700 | lock_res_and_lock(lock); |
| 1701 | list_del_init(&lock->l_bl_ast); |
| 1702 | |
| 1703 | LASSERT(lock->l_flags & LDLM_FL_AST_SENT); |
| 1704 | LASSERT(lock->l_bl_ast_run == 0); |
| 1705 | LASSERT(lock->l_blocking_lock); |
| 1706 | lock->l_bl_ast_run++; |
| 1707 | unlock_res_and_lock(lock); |
| 1708 | |
| 1709 | ldlm_lock2desc(lock->l_blocking_lock, &d); |
| 1710 | |
| 1711 | rc = lock->l_blocking_ast(lock, &d, (void *)arg, LDLM_CB_BLOCKING); |
| 1712 | LDLM_LOCK_RELEASE(lock->l_blocking_lock); |
| 1713 | lock->l_blocking_lock = NULL; |
| 1714 | LDLM_LOCK_RELEASE(lock); |
| 1715 | |
| 1716 | return rc; |
| 1717 | } |
| 1718 | |
| 1719 | /** |
| 1720 | * Process a call to completion AST callback for a lock in ast_work list |
| 1721 | */ |
| 1722 | static int |
| 1723 | ldlm_work_cp_ast_lock(struct ptlrpc_request_set *rqset, void *opaq) |
| 1724 | { |
| 1725 | struct ldlm_cb_set_arg *arg = opaq; |
| 1726 | int rc = 0; |
| 1727 | struct ldlm_lock *lock; |
| 1728 | ldlm_completion_callback completion_callback; |
| 1729 | |
| 1730 | if (list_empty(arg->list)) |
| 1731 | return -ENOENT; |
| 1732 | |
| 1733 | lock = list_entry(arg->list->next, struct ldlm_lock, l_cp_ast); |
| 1734 | |
| 1735 | /* It's possible to receive a completion AST before we've set |
| 1736 | * the l_completion_ast pointer: either because the AST arrived |
| 1737 | * before the reply, or simply because there's a small race |
| 1738 | * window between receiving the reply and finishing the local |
| 1739 | * enqueue. (bug 842) |
| 1740 | * |
| 1741 | * This can't happen with the blocking_ast, however, because we |
| 1742 | * will never call the local blocking_ast until we drop our |
| 1743 | * reader/writer reference, which we won't do until we get the |
| 1744 | * reply and finish enqueueing. */ |
| 1745 | |
| 1746 | /* nobody should touch l_cp_ast */ |
| 1747 | lock_res_and_lock(lock); |
| 1748 | list_del_init(&lock->l_cp_ast); |
| 1749 | LASSERT(lock->l_flags & LDLM_FL_CP_REQD); |
| 1750 | /* save l_completion_ast since it can be changed by |
| 1751 | * mds_intent_policy(), see bug 14225 */ |
| 1752 | completion_callback = lock->l_completion_ast; |
| 1753 | lock->l_flags &= ~LDLM_FL_CP_REQD; |
| 1754 | unlock_res_and_lock(lock); |
| 1755 | |
| 1756 | if (completion_callback != NULL) |
| 1757 | rc = completion_callback(lock, 0, (void *)arg); |
| 1758 | LDLM_LOCK_RELEASE(lock); |
| 1759 | |
| 1760 | return rc; |
| 1761 | } |
| 1762 | |
| 1763 | /** |
| 1764 | * Process a call to revocation AST callback for a lock in ast_work list |
| 1765 | */ |
| 1766 | static int |
| 1767 | ldlm_work_revoke_ast_lock(struct ptlrpc_request_set *rqset, void *opaq) |
| 1768 | { |
| 1769 | struct ldlm_cb_set_arg *arg = opaq; |
| 1770 | struct ldlm_lock_desc desc; |
| 1771 | int rc; |
| 1772 | struct ldlm_lock *lock; |
| 1773 | |
| 1774 | if (list_empty(arg->list)) |
| 1775 | return -ENOENT; |
| 1776 | |
| 1777 | lock = list_entry(arg->list->next, struct ldlm_lock, l_rk_ast); |
| 1778 | list_del_init(&lock->l_rk_ast); |
| 1779 | |
| 1780 | /* the desc just pretend to exclusive */ |
| 1781 | ldlm_lock2desc(lock, &desc); |
| 1782 | desc.l_req_mode = LCK_EX; |
| 1783 | desc.l_granted_mode = 0; |
| 1784 | |
| 1785 | rc = lock->l_blocking_ast(lock, &desc, (void*)arg, LDLM_CB_BLOCKING); |
| 1786 | LDLM_LOCK_RELEASE(lock); |
| 1787 | |
| 1788 | return rc; |
| 1789 | } |
| 1790 | |
| 1791 | /** |
| 1792 | * Process a call to glimpse AST callback for a lock in ast_work list |
| 1793 | */ |
| 1794 | int ldlm_work_gl_ast_lock(struct ptlrpc_request_set *rqset, void *opaq) |
| 1795 | { |
| 1796 | struct ldlm_cb_set_arg *arg = opaq; |
| 1797 | struct ldlm_glimpse_work *gl_work; |
| 1798 | struct ldlm_lock *lock; |
| 1799 | int rc = 0; |
| 1800 | |
| 1801 | if (list_empty(arg->list)) |
| 1802 | return -ENOENT; |
| 1803 | |
| 1804 | gl_work = list_entry(arg->list->next, struct ldlm_glimpse_work, |
| 1805 | gl_list); |
| 1806 | list_del_init(&gl_work->gl_list); |
| 1807 | |
| 1808 | lock = gl_work->gl_lock; |
| 1809 | |
| 1810 | /* transfer the glimpse descriptor to ldlm_cb_set_arg */ |
| 1811 | arg->gl_desc = gl_work->gl_desc; |
| 1812 | |
| 1813 | /* invoke the actual glimpse callback */ |
| 1814 | if (lock->l_glimpse_ast(lock, (void*)arg) == 0) |
| 1815 | rc = 1; |
| 1816 | |
| 1817 | LDLM_LOCK_RELEASE(lock); |
| 1818 | |
| 1819 | if ((gl_work->gl_flags & LDLM_GL_WORK_NOFREE) == 0) |
| 1820 | OBD_FREE_PTR(gl_work); |
| 1821 | |
| 1822 | return rc; |
| 1823 | } |
| 1824 | |
| 1825 | /** |
| 1826 | * Process list of locks in need of ASTs being sent. |
| 1827 | * |
| 1828 | * Used on server to send multiple ASTs together instead of sending one by |
| 1829 | * one. |
| 1830 | */ |
| 1831 | int ldlm_run_ast_work(struct ldlm_namespace *ns, struct list_head *rpc_list, |
| 1832 | ldlm_desc_ast_t ast_type) |
| 1833 | { |
| 1834 | struct ldlm_cb_set_arg *arg; |
| 1835 | set_producer_func work_ast_lock; |
| 1836 | int rc; |
| 1837 | |
| 1838 | if (list_empty(rpc_list)) |
| 1839 | return 0; |
| 1840 | |
| 1841 | OBD_ALLOC_PTR(arg); |
| 1842 | if (arg == NULL) |
| 1843 | return -ENOMEM; |
| 1844 | |
| 1845 | atomic_set(&arg->restart, 0); |
| 1846 | arg->list = rpc_list; |
| 1847 | |
| 1848 | switch (ast_type) { |
| 1849 | case LDLM_WORK_BL_AST: |
| 1850 | arg->type = LDLM_BL_CALLBACK; |
| 1851 | work_ast_lock = ldlm_work_bl_ast_lock; |
| 1852 | break; |
| 1853 | case LDLM_WORK_CP_AST: |
| 1854 | arg->type = LDLM_CP_CALLBACK; |
| 1855 | work_ast_lock = ldlm_work_cp_ast_lock; |
| 1856 | break; |
| 1857 | case LDLM_WORK_REVOKE_AST: |
| 1858 | arg->type = LDLM_BL_CALLBACK; |
| 1859 | work_ast_lock = ldlm_work_revoke_ast_lock; |
| 1860 | break; |
| 1861 | case LDLM_WORK_GL_AST: |
| 1862 | arg->type = LDLM_GL_CALLBACK; |
| 1863 | work_ast_lock = ldlm_work_gl_ast_lock; |
| 1864 | break; |
| 1865 | default: |
| 1866 | LBUG(); |
| 1867 | } |
| 1868 | |
| 1869 | /* We create a ptlrpc request set with flow control extension. |
| 1870 | * This request set will use the work_ast_lock function to produce new |
| 1871 | * requests and will send a new request each time one completes in order |
| 1872 | * to keep the number of requests in flight to ns_max_parallel_ast */ |
| 1873 | arg->set = ptlrpc_prep_fcset(ns->ns_max_parallel_ast ? : UINT_MAX, |
| 1874 | work_ast_lock, arg); |
| 1875 | if (arg->set == NULL) |
| 1876 | GOTO(out, rc = -ENOMEM); |
| 1877 | |
| 1878 | ptlrpc_set_wait(arg->set); |
| 1879 | ptlrpc_set_destroy(arg->set); |
| 1880 | |
| 1881 | rc = atomic_read(&arg->restart) ? -ERESTART : 0; |
| 1882 | GOTO(out, rc); |
| 1883 | out: |
| 1884 | OBD_FREE_PTR(arg); |
| 1885 | return rc; |
| 1886 | } |
| 1887 | |
| 1888 | static int reprocess_one_queue(struct ldlm_resource *res, void *closure) |
| 1889 | { |
| 1890 | ldlm_reprocess_all(res); |
| 1891 | return LDLM_ITER_CONTINUE; |
| 1892 | } |
| 1893 | |
| 1894 | static int ldlm_reprocess_res(cfs_hash_t *hs, cfs_hash_bd_t *bd, |
| 1895 | struct hlist_node *hnode, void *arg) |
| 1896 | { |
| 1897 | struct ldlm_resource *res = cfs_hash_object(hs, hnode); |
| 1898 | int rc; |
| 1899 | |
| 1900 | rc = reprocess_one_queue(res, arg); |
| 1901 | |
| 1902 | return rc == LDLM_ITER_STOP; |
| 1903 | } |
| 1904 | |
| 1905 | /** |
| 1906 | * Iterate through all resources on a namespace attempting to grant waiting |
| 1907 | * locks. |
| 1908 | */ |
| 1909 | void ldlm_reprocess_all_ns(struct ldlm_namespace *ns) |
| 1910 | { |
| 1911 | if (ns != NULL) { |
| 1912 | cfs_hash_for_each_nolock(ns->ns_rs_hash, |
| 1913 | ldlm_reprocess_res, NULL); |
| 1914 | } |
| 1915 | } |
| 1916 | EXPORT_SYMBOL(ldlm_reprocess_all_ns); |
| 1917 | |
| 1918 | /** |
| 1919 | * Try to grant all waiting locks on a resource. |
| 1920 | * |
| 1921 | * Calls ldlm_reprocess_queue on converting and waiting queues. |
| 1922 | * |
| 1923 | * Typically called after some resource locks are cancelled to see |
| 1924 | * if anything could be granted as a result of the cancellation. |
| 1925 | */ |
| 1926 | void ldlm_reprocess_all(struct ldlm_resource *res) |
| 1927 | { |
| 1928 | LIST_HEAD(rpc_list); |
| 1929 | |
| 1930 | if (!ns_is_client(ldlm_res_to_ns(res))) { |
| 1931 | CERROR("This is client-side-only module, cannot handle " |
| 1932 | "LDLM_NAMESPACE_SERVER resource type lock.\n"); |
| 1933 | LBUG(); |
| 1934 | } |
| 1935 | } |
| 1936 | |
| 1937 | /** |
| 1938 | * Helper function to call blocking AST for LDLM lock \a lock in a |
| 1939 | * "cancelling" mode. |
| 1940 | */ |
| 1941 | void ldlm_cancel_callback(struct ldlm_lock *lock) |
| 1942 | { |
| 1943 | check_res_locked(lock->l_resource); |
| 1944 | if (!(lock->l_flags & LDLM_FL_CANCEL)) { |
| 1945 | lock->l_flags |= LDLM_FL_CANCEL; |
| 1946 | if (lock->l_blocking_ast) { |
| 1947 | unlock_res_and_lock(lock); |
| 1948 | lock->l_blocking_ast(lock, NULL, lock->l_ast_data, |
| 1949 | LDLM_CB_CANCELING); |
| 1950 | lock_res_and_lock(lock); |
| 1951 | } else { |
| 1952 | LDLM_DEBUG(lock, "no blocking ast"); |
| 1953 | } |
| 1954 | } |
| 1955 | lock->l_flags |= LDLM_FL_BL_DONE; |
| 1956 | } |
| 1957 | |
| 1958 | /** |
| 1959 | * Remove skiplist-enabled LDLM lock \a req from granted list |
| 1960 | */ |
| 1961 | void ldlm_unlink_lock_skiplist(struct ldlm_lock *req) |
| 1962 | { |
| 1963 | if (req->l_resource->lr_type != LDLM_PLAIN && |
| 1964 | req->l_resource->lr_type != LDLM_IBITS) |
| 1965 | return; |
| 1966 | |
| 1967 | list_del_init(&req->l_sl_policy); |
| 1968 | list_del_init(&req->l_sl_mode); |
| 1969 | } |
| 1970 | |
| 1971 | /** |
| 1972 | * Attempts to cancel LDLM lock \a lock that has no reader/writer references. |
| 1973 | */ |
| 1974 | void ldlm_lock_cancel(struct ldlm_lock *lock) |
| 1975 | { |
| 1976 | struct ldlm_resource *res; |
| 1977 | struct ldlm_namespace *ns; |
| 1978 | |
| 1979 | lock_res_and_lock(lock); |
| 1980 | |
| 1981 | res = lock->l_resource; |
| 1982 | ns = ldlm_res_to_ns(res); |
| 1983 | |
| 1984 | /* Please do not, no matter how tempting, remove this LBUG without |
| 1985 | * talking to me first. -phik */ |
| 1986 | if (lock->l_readers || lock->l_writers) { |
| 1987 | LDLM_ERROR(lock, "lock still has references"); |
| 1988 | LBUG(); |
| 1989 | } |
| 1990 | |
| 1991 | if (lock->l_flags & LDLM_FL_WAITED) |
| 1992 | ldlm_del_waiting_lock(lock); |
| 1993 | |
| 1994 | /* Releases cancel callback. */ |
| 1995 | ldlm_cancel_callback(lock); |
| 1996 | |
| 1997 | /* Yes, second time, just in case it was added again while we were |
| 1998 | * running with no res lock in ldlm_cancel_callback */ |
| 1999 | if (lock->l_flags & LDLM_FL_WAITED) |
| 2000 | ldlm_del_waiting_lock(lock); |
| 2001 | |
| 2002 | ldlm_resource_unlink_lock(lock); |
| 2003 | ldlm_lock_destroy_nolock(lock); |
| 2004 | |
| 2005 | if (lock->l_granted_mode == lock->l_req_mode) |
| 2006 | ldlm_pool_del(&ns->ns_pool, lock); |
| 2007 | |
| 2008 | /* Make sure we will not be called again for same lock what is possible |
| 2009 | * if not to zero out lock->l_granted_mode */ |
| 2010 | lock->l_granted_mode = LCK_MINMODE; |
| 2011 | unlock_res_and_lock(lock); |
| 2012 | } |
| 2013 | EXPORT_SYMBOL(ldlm_lock_cancel); |
| 2014 | |
| 2015 | /** |
| 2016 | * Set opaque data into the lock that only makes sense to upper layer. |
| 2017 | */ |
| 2018 | int ldlm_lock_set_data(struct lustre_handle *lockh, void *data) |
| 2019 | { |
| 2020 | struct ldlm_lock *lock = ldlm_handle2lock(lockh); |
| 2021 | int rc = -EINVAL; |
| 2022 | |
| 2023 | if (lock) { |
| 2024 | if (lock->l_ast_data == NULL) |
| 2025 | lock->l_ast_data = data; |
| 2026 | if (lock->l_ast_data == data) |
| 2027 | rc = 0; |
| 2028 | LDLM_LOCK_PUT(lock); |
| 2029 | } |
| 2030 | return rc; |
| 2031 | } |
| 2032 | EXPORT_SYMBOL(ldlm_lock_set_data); |
| 2033 | |
| 2034 | struct export_cl_data { |
| 2035 | struct obd_export *ecl_exp; |
| 2036 | int ecl_loop; |
| 2037 | }; |
| 2038 | |
| 2039 | /** |
| 2040 | * Iterator function for ldlm_cancel_locks_for_export. |
| 2041 | * Cancels passed locks. |
| 2042 | */ |
| 2043 | int ldlm_cancel_locks_for_export_cb(cfs_hash_t *hs, cfs_hash_bd_t *bd, |
| 2044 | struct hlist_node *hnode, void *data) |
| 2045 | |
| 2046 | { |
| 2047 | struct export_cl_data *ecl = (struct export_cl_data *)data; |
| 2048 | struct obd_export *exp = ecl->ecl_exp; |
| 2049 | struct ldlm_lock *lock = cfs_hash_object(hs, hnode); |
| 2050 | struct ldlm_resource *res; |
| 2051 | |
| 2052 | res = ldlm_resource_getref(lock->l_resource); |
| 2053 | LDLM_LOCK_GET(lock); |
| 2054 | |
| 2055 | LDLM_DEBUG(lock, "export %p", exp); |
| 2056 | ldlm_res_lvbo_update(res, NULL, 1); |
| 2057 | ldlm_lock_cancel(lock); |
| 2058 | ldlm_reprocess_all(res); |
| 2059 | ldlm_resource_putref(res); |
| 2060 | LDLM_LOCK_RELEASE(lock); |
| 2061 | |
| 2062 | ecl->ecl_loop++; |
| 2063 | if ((ecl->ecl_loop & -ecl->ecl_loop) == ecl->ecl_loop) { |
| 2064 | CDEBUG(D_INFO, |
| 2065 | "Cancel lock %p for export %p (loop %d), still have " |
| 2066 | "%d locks left on hash table.\n", |
| 2067 | lock, exp, ecl->ecl_loop, |
| 2068 | atomic_read(&hs->hs_count)); |
| 2069 | } |
| 2070 | |
| 2071 | return 0; |
| 2072 | } |
| 2073 | |
| 2074 | /** |
| 2075 | * Cancel all locks for given export. |
| 2076 | * |
| 2077 | * Typically called on client disconnection/eviction |
| 2078 | */ |
| 2079 | void ldlm_cancel_locks_for_export(struct obd_export *exp) |
| 2080 | { |
| 2081 | struct export_cl_data ecl = { |
| 2082 | .ecl_exp = exp, |
| 2083 | .ecl_loop = 0, |
| 2084 | }; |
| 2085 | |
| 2086 | cfs_hash_for_each_empty(exp->exp_lock_hash, |
| 2087 | ldlm_cancel_locks_for_export_cb, &ecl); |
| 2088 | } |
| 2089 | |
| 2090 | /** |
| 2091 | * Downgrade an exclusive lock. |
| 2092 | * |
| 2093 | * A fast variant of ldlm_lock_convert for convertion of exclusive |
| 2094 | * locks. The convertion is always successful. |
| 2095 | * Used by Commit on Sharing (COS) code. |
| 2096 | * |
| 2097 | * \param lock A lock to convert |
| 2098 | * \param new_mode new lock mode |
| 2099 | */ |
| 2100 | void ldlm_lock_downgrade(struct ldlm_lock *lock, int new_mode) |
| 2101 | { |
| 2102 | LASSERT(lock->l_granted_mode & (LCK_PW | LCK_EX)); |
| 2103 | LASSERT(new_mode == LCK_COS); |
| 2104 | |
| 2105 | lock_res_and_lock(lock); |
| 2106 | ldlm_resource_unlink_lock(lock); |
| 2107 | /* |
| 2108 | * Remove the lock from pool as it will be added again in |
| 2109 | * ldlm_grant_lock() called below. |
| 2110 | */ |
| 2111 | ldlm_pool_del(&ldlm_lock_to_ns(lock)->ns_pool, lock); |
| 2112 | |
| 2113 | lock->l_req_mode = new_mode; |
| 2114 | ldlm_grant_lock(lock, NULL); |
| 2115 | unlock_res_and_lock(lock); |
| 2116 | ldlm_reprocess_all(lock->l_resource); |
| 2117 | } |
| 2118 | EXPORT_SYMBOL(ldlm_lock_downgrade); |
| 2119 | |
| 2120 | /** |
| 2121 | * Attempt to convert already granted lock to a different mode. |
| 2122 | * |
| 2123 | * While lock conversion is not currently used, future client-side |
| 2124 | * optimizations could take advantage of it to avoid discarding cached |
| 2125 | * pages on a file. |
| 2126 | */ |
| 2127 | struct ldlm_resource *ldlm_lock_convert(struct ldlm_lock *lock, int new_mode, |
| 2128 | __u32 *flags) |
| 2129 | { |
| 2130 | LIST_HEAD(rpc_list); |
| 2131 | struct ldlm_resource *res; |
| 2132 | struct ldlm_namespace *ns; |
| 2133 | int granted = 0; |
| 2134 | struct ldlm_interval *node; |
| 2135 | |
| 2136 | /* Just return if mode is unchanged. */ |
| 2137 | if (new_mode == lock->l_granted_mode) { |
| 2138 | *flags |= LDLM_FL_BLOCK_GRANTED; |
| 2139 | return lock->l_resource; |
| 2140 | } |
| 2141 | |
| 2142 | /* I can't check the type of lock here because the bitlock of lock |
| 2143 | * is not held here, so do the allocation blindly. -jay */ |
| 2144 | OBD_SLAB_ALLOC_PTR_GFP(node, ldlm_interval_slab, __GFP_IO); |
| 2145 | if (node == NULL) |
| 2146 | /* Actually, this causes EDEADLOCK to be returned */ |
| 2147 | return NULL; |
| 2148 | |
| 2149 | LASSERTF((new_mode == LCK_PW && lock->l_granted_mode == LCK_PR), |
| 2150 | "new_mode %u, granted %u\n", new_mode, lock->l_granted_mode); |
| 2151 | |
| 2152 | lock_res_and_lock(lock); |
| 2153 | |
| 2154 | res = lock->l_resource; |
| 2155 | ns = ldlm_res_to_ns(res); |
| 2156 | |
| 2157 | lock->l_req_mode = new_mode; |
| 2158 | if (res->lr_type == LDLM_PLAIN || res->lr_type == LDLM_IBITS) { |
| 2159 | ldlm_resource_unlink_lock(lock); |
| 2160 | } else { |
| 2161 | ldlm_resource_unlink_lock(lock); |
| 2162 | if (res->lr_type == LDLM_EXTENT) { |
| 2163 | /* FIXME: ugly code, I have to attach the lock to a |
| 2164 | * interval node again since perhaps it will be granted |
| 2165 | * soon */ |
| 2166 | INIT_LIST_HEAD(&node->li_group); |
| 2167 | ldlm_interval_attach(node, lock); |
| 2168 | node = NULL; |
| 2169 | } |
| 2170 | } |
| 2171 | |
| 2172 | /* |
| 2173 | * Remove old lock from the pool before adding the lock with new |
| 2174 | * mode below in ->policy() |
| 2175 | */ |
| 2176 | ldlm_pool_del(&ns->ns_pool, lock); |
| 2177 | |
| 2178 | /* If this is a local resource, put it on the appropriate list. */ |
| 2179 | if (ns_is_client(ldlm_res_to_ns(res))) { |
| 2180 | if (*flags & (LDLM_FL_BLOCK_CONV | LDLM_FL_BLOCK_GRANTED)) { |
| 2181 | ldlm_resource_add_lock(res, &res->lr_converting, lock); |
| 2182 | } else { |
| 2183 | /* This should never happen, because of the way the |
| 2184 | * server handles conversions. */ |
| 2185 | LDLM_ERROR(lock, "Erroneous flags %x on local lock\n", |
| 2186 | *flags); |
| 2187 | LBUG(); |
| 2188 | |
| 2189 | ldlm_grant_lock(lock, &rpc_list); |
| 2190 | granted = 1; |
| 2191 | /* FIXME: completion handling not with lr_lock held ! */ |
| 2192 | if (lock->l_completion_ast) |
| 2193 | lock->l_completion_ast(lock, 0, NULL); |
| 2194 | } |
| 2195 | } else { |
| 2196 | CERROR("This is client-side-only module, cannot handle " |
| 2197 | "LDLM_NAMESPACE_SERVER resource type lock.\n"); |
| 2198 | LBUG(); |
| 2199 | } |
| 2200 | unlock_res_and_lock(lock); |
| 2201 | |
| 2202 | if (granted) |
| 2203 | ldlm_run_ast_work(ns, &rpc_list, LDLM_WORK_CP_AST); |
| 2204 | if (node) |
| 2205 | OBD_SLAB_FREE(node, ldlm_interval_slab, sizeof(*node)); |
| 2206 | return res; |
| 2207 | } |
| 2208 | EXPORT_SYMBOL(ldlm_lock_convert); |
| 2209 | |
| 2210 | /** |
| 2211 | * Print lock with lock handle \a lockh description into debug log. |
| 2212 | * |
| 2213 | * Used when printing all locks on a resource for debug purposes. |
| 2214 | */ |
| 2215 | void ldlm_lock_dump_handle(int level, struct lustre_handle *lockh) |
| 2216 | { |
| 2217 | struct ldlm_lock *lock; |
| 2218 | |
| 2219 | if (!((libcfs_debug | D_ERROR) & level)) |
| 2220 | return; |
| 2221 | |
| 2222 | lock = ldlm_handle2lock(lockh); |
| 2223 | if (lock == NULL) |
| 2224 | return; |
| 2225 | |
| 2226 | LDLM_DEBUG_LIMIT(level, lock, "###"); |
| 2227 | |
| 2228 | LDLM_LOCK_PUT(lock); |
| 2229 | } |
| 2230 | EXPORT_SYMBOL(ldlm_lock_dump_handle); |
| 2231 | |
| 2232 | /** |
| 2233 | * Print lock information with custom message into debug log. |
| 2234 | * Helper function. |
| 2235 | */ |
| 2236 | void _ldlm_lock_debug(struct ldlm_lock *lock, |
| 2237 | struct libcfs_debug_msg_data *msgdata, |
| 2238 | const char *fmt, ...) |
| 2239 | { |
| 2240 | va_list args; |
| 2241 | struct obd_export *exp = lock->l_export; |
| 2242 | struct ldlm_resource *resource = lock->l_resource; |
| 2243 | char *nid = "local"; |
| 2244 | |
| 2245 | va_start(args, fmt); |
| 2246 | |
| 2247 | if (exp && exp->exp_connection) { |
| 2248 | nid = libcfs_nid2str(exp->exp_connection->c_peer.nid); |
| 2249 | } else if (exp && exp->exp_obd != NULL) { |
| 2250 | struct obd_import *imp = exp->exp_obd->u.cli.cl_import; |
| 2251 | nid = libcfs_nid2str(imp->imp_connection->c_peer.nid); |
| 2252 | } |
| 2253 | |
| 2254 | if (resource == NULL) { |
| 2255 | libcfs_debug_vmsg2(msgdata, fmt, args, |
| 2256 | " ns: \?\? lock: %p/"LPX64" lrc: %d/%d,%d mode: %s/%s " |
| 2257 | "res: \?\? rrc=\?\? type: \?\?\? flags: "LPX64" nid: %s " |
| 2258 | "remote: "LPX64" expref: %d pid: %u timeout: %lu " |
| 2259 | "lvb_type: %d\n", |
| 2260 | lock, |
| 2261 | lock->l_handle.h_cookie, atomic_read(&lock->l_refc), |
| 2262 | lock->l_readers, lock->l_writers, |
| 2263 | ldlm_lockname[lock->l_granted_mode], |
| 2264 | ldlm_lockname[lock->l_req_mode], |
| 2265 | lock->l_flags, nid, lock->l_remote_handle.cookie, |
| 2266 | exp ? atomic_read(&exp->exp_refcount) : -99, |
| 2267 | lock->l_pid, lock->l_callback_timeout, lock->l_lvb_type); |
| 2268 | va_end(args); |
| 2269 | return; |
| 2270 | } |
| 2271 | |
| 2272 | switch (resource->lr_type) { |
| 2273 | case LDLM_EXTENT: |
| 2274 | libcfs_debug_vmsg2(msgdata, fmt, args, |
| 2275 | " ns: %s lock: %p/"LPX64" lrc: %d/%d,%d mode: %s/%s " |
| 2276 | "res: "DLDLMRES" rrc: %d type: %s ["LPU64"->"LPU64"] " |
| 2277 | "(req "LPU64"->"LPU64") flags: "LPX64" nid: %s remote: " |
| 2278 | LPX64" expref: %d pid: %u timeout: %lu lvb_type: %d\n", |
| 2279 | ldlm_lock_to_ns_name(lock), lock, |
| 2280 | lock->l_handle.h_cookie, atomic_read(&lock->l_refc), |
| 2281 | lock->l_readers, lock->l_writers, |
| 2282 | ldlm_lockname[lock->l_granted_mode], |
| 2283 | ldlm_lockname[lock->l_req_mode], |
| 2284 | PLDLMRES(resource), |
| 2285 | atomic_read(&resource->lr_refcount), |
| 2286 | ldlm_typename[resource->lr_type], |
| 2287 | lock->l_policy_data.l_extent.start, |
| 2288 | lock->l_policy_data.l_extent.end, |
| 2289 | lock->l_req_extent.start, lock->l_req_extent.end, |
| 2290 | lock->l_flags, nid, lock->l_remote_handle.cookie, |
| 2291 | exp ? atomic_read(&exp->exp_refcount) : -99, |
| 2292 | lock->l_pid, lock->l_callback_timeout, |
| 2293 | lock->l_lvb_type); |
| 2294 | break; |
| 2295 | |
| 2296 | case LDLM_FLOCK: |
| 2297 | libcfs_debug_vmsg2(msgdata, fmt, args, |
| 2298 | " ns: %s lock: %p/"LPX64" lrc: %d/%d,%d mode: %s/%s " |
| 2299 | "res: "DLDLMRES" rrc: %d type: %s pid: %d " |
| 2300 | "["LPU64"->"LPU64"] flags: "LPX64" nid: %s " |
| 2301 | "remote: "LPX64" expref: %d pid: %u timeout: %lu\n", |
| 2302 | ldlm_lock_to_ns_name(lock), lock, |
| 2303 | lock->l_handle.h_cookie, atomic_read(&lock->l_refc), |
| 2304 | lock->l_readers, lock->l_writers, |
| 2305 | ldlm_lockname[lock->l_granted_mode], |
| 2306 | ldlm_lockname[lock->l_req_mode], |
| 2307 | PLDLMRES(resource), |
| 2308 | atomic_read(&resource->lr_refcount), |
| 2309 | ldlm_typename[resource->lr_type], |
| 2310 | lock->l_policy_data.l_flock.pid, |
| 2311 | lock->l_policy_data.l_flock.start, |
| 2312 | lock->l_policy_data.l_flock.end, |
| 2313 | lock->l_flags, nid, lock->l_remote_handle.cookie, |
| 2314 | exp ? atomic_read(&exp->exp_refcount) : -99, |
| 2315 | lock->l_pid, lock->l_callback_timeout); |
| 2316 | break; |
| 2317 | |
| 2318 | case LDLM_IBITS: |
| 2319 | libcfs_debug_vmsg2(msgdata, fmt, args, |
| 2320 | " ns: %s lock: %p/"LPX64" lrc: %d/%d,%d mode: %s/%s " |
| 2321 | "res: "DLDLMRES" bits "LPX64" rrc: %d type: %s " |
| 2322 | "flags: "LPX64" nid: %s remote: "LPX64" expref: %d " |
| 2323 | "pid: %u timeout: %lu lvb_type: %d\n", |
| 2324 | ldlm_lock_to_ns_name(lock), |
| 2325 | lock, lock->l_handle.h_cookie, |
| 2326 | atomic_read(&lock->l_refc), |
| 2327 | lock->l_readers, lock->l_writers, |
| 2328 | ldlm_lockname[lock->l_granted_mode], |
| 2329 | ldlm_lockname[lock->l_req_mode], |
| 2330 | PLDLMRES(resource), |
| 2331 | lock->l_policy_data.l_inodebits.bits, |
| 2332 | atomic_read(&resource->lr_refcount), |
| 2333 | ldlm_typename[resource->lr_type], |
| 2334 | lock->l_flags, nid, lock->l_remote_handle.cookie, |
| 2335 | exp ? atomic_read(&exp->exp_refcount) : -99, |
| 2336 | lock->l_pid, lock->l_callback_timeout, |
| 2337 | lock->l_lvb_type); |
| 2338 | break; |
| 2339 | |
| 2340 | default: |
| 2341 | libcfs_debug_vmsg2(msgdata, fmt, args, |
| 2342 | " ns: %s lock: %p/"LPX64" lrc: %d/%d,%d mode: %s/%s " |
| 2343 | "res: "DLDLMRES" rrc: %d type: %s flags: "LPX64" " |
| 2344 | "nid: %s remote: "LPX64" expref: %d pid: %u " |
| 2345 | "timeout: %lu lvb_type: %d\n", |
| 2346 | ldlm_lock_to_ns_name(lock), |
| 2347 | lock, lock->l_handle.h_cookie, |
| 2348 | atomic_read(&lock->l_refc), |
| 2349 | lock->l_readers, lock->l_writers, |
| 2350 | ldlm_lockname[lock->l_granted_mode], |
| 2351 | ldlm_lockname[lock->l_req_mode], |
| 2352 | PLDLMRES(resource), |
| 2353 | atomic_read(&resource->lr_refcount), |
| 2354 | ldlm_typename[resource->lr_type], |
| 2355 | lock->l_flags, nid, lock->l_remote_handle.cookie, |
| 2356 | exp ? atomic_read(&exp->exp_refcount) : -99, |
| 2357 | lock->l_pid, lock->l_callback_timeout, |
| 2358 | lock->l_lvb_type); |
| 2359 | break; |
| 2360 | } |
| 2361 | va_end(args); |
| 2362 | } |
| 2363 | EXPORT_SYMBOL(_ldlm_lock_debug); |