/* * GPL HEADER START * * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 only, * as published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License version 2 for more details (a copy is included * in the LICENSE file that accompanied this code). * * You should have received a copy of the GNU General Public License * version 2 along with this program; If not, see * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf * * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, * CA 95054 USA or visit www.sun.com if you need additional information or * have any questions. * * GPL HEADER END */ /* * Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved. * Use is subject to license terms. * * Copyright (c) 2010, 2014, Intel Corporation. */ /* * This file is part of Lustre, http://www.lustre.org/ * Lustre is a trademark of Sun Microsystems, Inc. * * lustre/ldlm/ldlm_lock.c * * Author: Peter Braam * Author: Phil Schwan */ #define DEBUG_SUBSYSTEM S_LDLM #include #include #include "ldlm_internal.h" /* lock types */ char *ldlm_lockname[] = { [0] = "--", [LCK_EX] = "EX", [LCK_PW] = "PW", [LCK_PR] = "PR", [LCK_CW] = "CW", [LCK_CR] = "CR", [LCK_NL] = "NL", [LCK_GROUP] = "GROUP", [LCK_COS] = "COS" }; EXPORT_SYMBOL(ldlm_lockname); char *ldlm_typename[] = { [LDLM_PLAIN] = "PLN", [LDLM_EXTENT] = "EXT", [LDLM_FLOCK] = "FLK", [LDLM_IBITS] = "IBT", }; static ldlm_policy_wire_to_local_t ldlm_policy_wire_to_local[] = { [LDLM_PLAIN - LDLM_MIN_TYPE] = ldlm_plain_policy_wire_to_local, [LDLM_EXTENT - LDLM_MIN_TYPE] = ldlm_extent_policy_wire_to_local, [LDLM_FLOCK - LDLM_MIN_TYPE] = ldlm_flock_policy_wire_to_local, [LDLM_IBITS - LDLM_MIN_TYPE] = ldlm_ibits_policy_wire_to_local, }; static ldlm_policy_local_to_wire_t ldlm_policy_local_to_wire[] = { [LDLM_PLAIN - LDLM_MIN_TYPE] = ldlm_plain_policy_local_to_wire, [LDLM_EXTENT - LDLM_MIN_TYPE] = ldlm_extent_policy_local_to_wire, [LDLM_FLOCK - LDLM_MIN_TYPE] = ldlm_flock_policy_local_to_wire, [LDLM_IBITS - LDLM_MIN_TYPE] = ldlm_ibits_policy_local_to_wire, }; /** * Converts lock policy from local format to on the wire lock_desc format */ void ldlm_convert_policy_to_wire(enum ldlm_type type, const union ldlm_policy_data *lpolicy, union ldlm_wire_policy_data *wpolicy) { ldlm_policy_local_to_wire_t convert; convert = ldlm_policy_local_to_wire[type - LDLM_MIN_TYPE]; convert(lpolicy, wpolicy); } /** * Converts lock policy from on the wire lock_desc format to local format */ void ldlm_convert_policy_to_local(struct obd_export *exp, enum ldlm_type type, const union ldlm_wire_policy_data *wpolicy, union ldlm_policy_data *lpolicy) { ldlm_policy_wire_to_local_t convert; convert = ldlm_policy_wire_to_local[type - LDLM_MIN_TYPE]; convert(wpolicy, lpolicy); } const char *ldlm_it2str(enum ldlm_intent_flags it) { switch (it) { case IT_OPEN: return "open"; case IT_CREAT: return "creat"; case (IT_OPEN | IT_CREAT): return "open|creat"; case IT_READDIR: return "readdir"; case IT_GETATTR: return "getattr"; case IT_LOOKUP: return "lookup"; case IT_UNLINK: return "unlink"; case IT_GETXATTR: return "getxattr"; case IT_LAYOUT: return "layout"; default: CERROR("Unknown intent 0x%08x\n", it); return "UNKNOWN"; } } EXPORT_SYMBOL(ldlm_it2str); extern struct kmem_cache *ldlm_lock_slab; #ifdef HAVE_SERVER_SUPPORT static ldlm_processing_policy ldlm_processing_policy_table[] = { [LDLM_PLAIN] = ldlm_process_plain_lock, [LDLM_EXTENT] = ldlm_process_extent_lock, [LDLM_FLOCK] = ldlm_process_flock_lock, [LDLM_IBITS] = ldlm_process_inodebits_lock, }; ldlm_processing_policy ldlm_get_processing_policy(struct ldlm_resource *res) { return ldlm_processing_policy_table[res->lr_type]; } EXPORT_SYMBOL(ldlm_get_processing_policy); #endif /* HAVE_SERVER_SUPPORT */ void ldlm_register_intent(struct ldlm_namespace *ns, ldlm_res_policy arg) { ns->ns_policy = arg; } EXPORT_SYMBOL(ldlm_register_intent); /* * REFCOUNTED LOCK OBJECTS */ /** * Get a reference on a lock. * * Lock refcounts, during creation: * - one special one for allocation, dec'd only once in destroy * - one for being a lock that's in-use * - one for the addref associated with a new lock */ struct ldlm_lock *ldlm_lock_get(struct ldlm_lock *lock) { atomic_inc(&lock->l_refc); return lock; } EXPORT_SYMBOL(ldlm_lock_get); /** * Release lock reference. * * Also frees the lock if it was last reference. */ void ldlm_lock_put(struct ldlm_lock *lock) { ENTRY; LASSERT(lock->l_resource != LP_POISON); LASSERT(atomic_read(&lock->l_refc) > 0); if (atomic_dec_and_test(&lock->l_refc)) { struct ldlm_resource *res; LDLM_DEBUG(lock, "final lock_put on destroyed lock, freeing it."); res = lock->l_resource; LASSERT(ldlm_is_destroyed(lock)); LASSERT(list_empty(&lock->l_exp_list)); LASSERT(list_empty(&lock->l_res_link)); LASSERT(list_empty(&lock->l_pending_chain)); lprocfs_counter_decr(ldlm_res_to_ns(res)->ns_stats, LDLM_NSS_LOCKS); lu_ref_del(&res->lr_reference, "lock", lock); ldlm_resource_putref(res); lock->l_resource = NULL; if (lock->l_export) { class_export_lock_put(lock->l_export, lock); lock->l_export = NULL; } if (lock->l_lvb_data != NULL) OBD_FREE_LARGE(lock->l_lvb_data, lock->l_lvb_len); ldlm_interval_free(ldlm_interval_detach(lock)); lu_ref_fini(&lock->l_reference); OBD_FREE_RCU(lock, sizeof(*lock), &lock->l_handle); } EXIT; } EXPORT_SYMBOL(ldlm_lock_put); /** * Removes LDLM lock \a lock from LRU. Assumes LRU is already locked. */ int ldlm_lock_remove_from_lru_nolock(struct ldlm_lock *lock) { int rc = 0; if (!list_empty(&lock->l_lru)) { struct ldlm_namespace *ns = ldlm_lock_to_ns(lock); LASSERT(lock->l_resource->lr_type != LDLM_FLOCK); list_del_init(&lock->l_lru); LASSERT(ns->ns_nr_unused > 0); ns->ns_nr_unused--; rc = 1; } return rc; } /** * Removes LDLM lock \a lock from LRU. Obtains the LRU lock first. * * If \a last_use is non-zero, it will remove the lock from LRU only if * it matches lock's l_last_used. * * \retval 0 if \a last_use is set, the lock is not in LRU list or \a last_use * doesn't match lock's l_last_used; * otherwise, the lock hasn't been in the LRU list. * \retval 1 the lock was in LRU list and removed. */ int ldlm_lock_remove_from_lru_check(struct ldlm_lock *lock, cfs_time_t last_use) { struct ldlm_namespace *ns = ldlm_lock_to_ns(lock); int rc = 0; ENTRY; if (ldlm_is_ns_srv(lock)) { LASSERT(list_empty(&lock->l_lru)); RETURN(0); } spin_lock(&ns->ns_lock); if (last_use == 0 || last_use == lock->l_last_used) rc = ldlm_lock_remove_from_lru_nolock(lock); spin_unlock(&ns->ns_lock); RETURN(rc); } /** * Adds LDLM lock \a lock to namespace LRU. Assumes LRU is already locked. */ void ldlm_lock_add_to_lru_nolock(struct ldlm_lock *lock) { struct ldlm_namespace *ns = ldlm_lock_to_ns(lock); lock->l_last_used = cfs_time_current(); LASSERT(list_empty(&lock->l_lru)); LASSERT(lock->l_resource->lr_type != LDLM_FLOCK); list_add_tail(&lock->l_lru, &ns->ns_unused_list); ldlm_clear_skipped(lock); LASSERT(ns->ns_nr_unused >= 0); ns->ns_nr_unused++; } /** * Adds LDLM lock \a lock to namespace LRU. Obtains necessary LRU locks * first. */ void ldlm_lock_add_to_lru(struct ldlm_lock *lock) { struct ldlm_namespace *ns = ldlm_lock_to_ns(lock); ENTRY; spin_lock(&ns->ns_lock); ldlm_lock_add_to_lru_nolock(lock); spin_unlock(&ns->ns_lock); EXIT; } /** * Moves LDLM lock \a lock that is already in namespace LRU to the tail of * the LRU. Performs necessary LRU locking */ void ldlm_lock_touch_in_lru(struct ldlm_lock *lock) { struct ldlm_namespace *ns = ldlm_lock_to_ns(lock); ENTRY; if (ldlm_is_ns_srv(lock)) { LASSERT(list_empty(&lock->l_lru)); EXIT; return; } spin_lock(&ns->ns_lock); if (!list_empty(&lock->l_lru)) { ldlm_lock_remove_from_lru_nolock(lock); ldlm_lock_add_to_lru_nolock(lock); } spin_unlock(&ns->ns_lock); EXIT; } /** * Helper to destroy a locked lock. * * Used by ldlm_lock_destroy and ldlm_lock_destroy_nolock * Must be called with l_lock and lr_lock held. * * Does not actually free the lock data, but rather marks the lock as * destroyed by setting l_destroyed field in the lock to 1. Destroys a * handle->lock association too, so that the lock can no longer be found * and removes the lock from LRU list. Actual lock freeing occurs when * last lock reference goes away. * * Original comment (of some historical value): * This used to have a 'strict' flag, which recovery would use to mark an * in-use lock as needing-to-die. Lest I am ever tempted to put it back, I * shall explain why it's gone: with the new hash table scheme, once you call * ldlm_lock_destroy, you can never drop your final references on this lock. * Because it's not in the hash table anymore. -phil */ static int ldlm_lock_destroy_internal(struct ldlm_lock *lock) { ENTRY; if (lock->l_readers || lock->l_writers) { LDLM_ERROR(lock, "lock still has references"); LBUG(); } if (!list_empty(&lock->l_res_link)) { LDLM_ERROR(lock, "lock still on resource"); LBUG(); } if (ldlm_is_destroyed(lock)) { LASSERT(list_empty(&lock->l_lru)); EXIT; return 0; } ldlm_set_destroyed(lock); if (lock->l_export && lock->l_export->exp_lock_hash) { /* NB: it's safe to call cfs_hash_del() even lock isn't * in exp_lock_hash. */ /* In the function below, .hs_keycmp resolves to * ldlm_export_lock_keycmp() */ /* coverity[overrun-buffer-val] */ cfs_hash_del(lock->l_export->exp_lock_hash, &lock->l_remote_handle, &lock->l_exp_hash); } ldlm_lock_remove_from_lru(lock); class_handle_unhash(&lock->l_handle); #if 0 /* Wake anyone waiting for this lock */ /* FIXME: I should probably add yet another flag, instead of using * l_export to only call this on clients */ if (lock->l_export) class_export_put(lock->l_export); lock->l_export = NULL; if (lock->l_export && lock->l_completion_ast) lock->l_completion_ast(lock, 0); #endif EXIT; return 1; } /** * Destroys a LDLM lock \a lock. Performs necessary locking first. */ void ldlm_lock_destroy(struct ldlm_lock *lock) { int first; ENTRY; lock_res_and_lock(lock); first = ldlm_lock_destroy_internal(lock); unlock_res_and_lock(lock); /* drop reference from hashtable only for first destroy */ if (first) { lu_ref_del(&lock->l_reference, "hash", lock); LDLM_LOCK_RELEASE(lock); } EXIT; } /** * Destroys a LDLM lock \a lock that is already locked. */ void ldlm_lock_destroy_nolock(struct ldlm_lock *lock) { int first; ENTRY; first = ldlm_lock_destroy_internal(lock); /* drop reference from hashtable only for first destroy */ if (first) { lu_ref_del(&lock->l_reference, "hash", lock); LDLM_LOCK_RELEASE(lock); } EXIT; } /* this is called by portals_handle2object with the handle lock taken */ static void lock_handle_addref(void *lock) { LDLM_LOCK_GET((struct ldlm_lock *)lock); } static void lock_handle_free(void *lock, int size) { LASSERT(size == sizeof(struct ldlm_lock)); OBD_SLAB_FREE(lock, ldlm_lock_slab, size); } static struct portals_handle_ops lock_handle_ops = { .hop_addref = lock_handle_addref, .hop_free = lock_handle_free, }; /** * * Allocate and initialize new lock structure. * * usage: pass in a resource on which you have done ldlm_resource_get * new lock will take over the refcount. * returns: lock with refcount 2 - one for current caller and one for remote */ static struct ldlm_lock *ldlm_lock_new(struct ldlm_resource *resource) { struct ldlm_lock *lock; ENTRY; if (resource == NULL) LBUG(); OBD_SLAB_ALLOC_PTR_GFP(lock, ldlm_lock_slab, GFP_NOFS); if (lock == NULL) RETURN(NULL); spin_lock_init(&lock->l_lock); lock->l_resource = resource; lu_ref_add(&resource->lr_reference, "lock", lock); atomic_set(&lock->l_refc, 2); INIT_LIST_HEAD(&lock->l_res_link); INIT_LIST_HEAD(&lock->l_lru); INIT_LIST_HEAD(&lock->l_pending_chain); INIT_LIST_HEAD(&lock->l_bl_ast); INIT_LIST_HEAD(&lock->l_cp_ast); INIT_LIST_HEAD(&lock->l_rk_ast); init_waitqueue_head(&lock->l_waitq); lock->l_blocking_lock = NULL; INIT_LIST_HEAD(&lock->l_sl_mode); INIT_LIST_HEAD(&lock->l_sl_policy); INIT_HLIST_NODE(&lock->l_exp_hash); INIT_HLIST_NODE(&lock->l_exp_flock_hash); lprocfs_counter_incr(ldlm_res_to_ns(resource)->ns_stats, LDLM_NSS_LOCKS); INIT_LIST_HEAD(&lock->l_handle.h_link); class_handle_hash(&lock->l_handle, &lock_handle_ops); lu_ref_init(&lock->l_reference); lu_ref_add(&lock->l_reference, "hash", lock); lock->l_callback_timeout = 0; #if LUSTRE_TRACKS_LOCK_EXP_REFS INIT_LIST_HEAD(&lock->l_exp_refs_link); lock->l_exp_refs_nr = 0; lock->l_exp_refs_target = NULL; #endif INIT_LIST_HEAD(&lock->l_exp_list); RETURN(lock); } /** * Moves LDLM lock \a lock to another resource. * This is used on client when server returns some other lock than requested * (typically as a result of intent operation) */ int ldlm_lock_change_resource(struct ldlm_namespace *ns, struct ldlm_lock *lock, const struct ldlm_res_id *new_resid) { struct ldlm_resource *oldres = lock->l_resource; struct ldlm_resource *newres; int type; ENTRY; LASSERT(ns_is_client(ns)); lock_res_and_lock(lock); if (memcmp(new_resid, &lock->l_resource->lr_name, sizeof(lock->l_resource->lr_name)) == 0) { /* Nothing to do */ unlock_res_and_lock(lock); RETURN(0); } LASSERT(new_resid->name[0] != 0); /* This function assumes that the lock isn't on any lists */ LASSERT(list_empty(&lock->l_res_link)); type = oldres->lr_type; unlock_res_and_lock(lock); newres = ldlm_resource_get(ns, NULL, new_resid, type, 1); if (IS_ERR(newres)) RETURN(PTR_ERR(newres)); lu_ref_add(&newres->lr_reference, "lock", lock); /* * To flip the lock from the old to the new resource, lock, oldres and * newres have to be locked. Resource spin-locks are nested within * lock->l_lock, and are taken in the memory address order to avoid * dead-locks. */ spin_lock(&lock->l_lock); oldres = lock->l_resource; if (oldres < newres) { lock_res(oldres); lock_res_nested(newres, LRT_NEW); } else { lock_res(newres); lock_res_nested(oldres, LRT_NEW); } LASSERT(memcmp(new_resid, &oldres->lr_name, sizeof oldres->lr_name) != 0); lock->l_resource = newres; unlock_res(oldres); unlock_res_and_lock(lock); /* ...and the flowers are still standing! */ lu_ref_del(&oldres->lr_reference, "lock", lock); ldlm_resource_putref(oldres); RETURN(0); } /** \defgroup ldlm_handles LDLM HANDLES * Ways to get hold of locks without any addresses. * @{ */ /** * Fills in handle for LDLM lock \a lock into supplied \a lockh * Does not take any references. */ void ldlm_lock2handle(const struct ldlm_lock *lock, struct lustre_handle *lockh) { lockh->cookie = lock->l_handle.h_cookie; } EXPORT_SYMBOL(ldlm_lock2handle); /** * Obtain a lock reference by handle. * * if \a flags: atomically get the lock and set the flags. * Return NULL if flag already set */ struct ldlm_lock *__ldlm_handle2lock(const struct lustre_handle *handle, __u64 flags) { struct ldlm_lock *lock; ENTRY; LASSERT(handle); lock = class_handle2object(handle->cookie, NULL); if (lock == NULL) RETURN(NULL); /* It's unlikely but possible that someone marked the lock as * destroyed after we did handle2object on it */ if ((flags == 0) && !ldlm_is_destroyed(lock)) { lu_ref_add(&lock->l_reference, "handle", current); RETURN(lock); } lock_res_and_lock(lock); LASSERT(lock->l_resource != NULL); lu_ref_add_atomic(&lock->l_reference, "handle", current); if (unlikely(ldlm_is_destroyed(lock))) { unlock_res_and_lock(lock); CDEBUG(D_INFO, "lock already destroyed: lock %p\n", lock); LDLM_LOCK_PUT(lock); RETURN(NULL); } /* If we're setting flags, make sure none of them are already set. */ if (flags != 0) { if ((lock->l_flags & flags) != 0) { unlock_res_and_lock(lock); LDLM_LOCK_PUT(lock); RETURN(NULL); } lock->l_flags |= flags; } unlock_res_and_lock(lock); RETURN(lock); } EXPORT_SYMBOL(__ldlm_handle2lock); /** @} ldlm_handles */ /** * Fill in "on the wire" representation for given LDLM lock into supplied * lock descriptor \a desc structure. */ void ldlm_lock2desc(struct ldlm_lock *lock, struct ldlm_lock_desc *desc) { ldlm_res2desc(lock->l_resource, &desc->l_resource); desc->l_req_mode = lock->l_req_mode; desc->l_granted_mode = lock->l_granted_mode; ldlm_convert_policy_to_wire(lock->l_resource->lr_type, &lock->l_policy_data, &desc->l_policy_data); } /** * Add a lock to list of conflicting locks to send AST to. * * Only add if we have not sent a blocking AST to the lock yet. */ static void ldlm_add_bl_work_item(struct ldlm_lock *lock, struct ldlm_lock *new, struct list_head *work_list) { if (!ldlm_is_ast_sent(lock)) { LDLM_DEBUG(lock, "lock incompatible; sending blocking AST."); ldlm_set_ast_sent(lock); /* If the enqueuing client said so, tell the AST recipient to * discard dirty data, rather than writing back. */ if (ldlm_is_ast_discard_data(new)) ldlm_set_discard_data(lock); LASSERT(list_empty(&lock->l_bl_ast)); list_add(&lock->l_bl_ast, work_list); LDLM_LOCK_GET(lock); LASSERT(lock->l_blocking_lock == NULL); lock->l_blocking_lock = LDLM_LOCK_GET(new); } } /** * Add a lock to list of just granted locks to send completion AST to. */ static void ldlm_add_cp_work_item(struct ldlm_lock *lock, struct list_head *work_list) { if (!ldlm_is_cp_reqd(lock)) { ldlm_set_cp_reqd(lock); LDLM_DEBUG(lock, "lock granted; sending completion AST."); LASSERT(list_empty(&lock->l_cp_ast)); list_add(&lock->l_cp_ast, work_list); LDLM_LOCK_GET(lock); } } /** * Aggregator function to add AST work items into a list. Determines * what sort of an AST work needs to be done and calls the proper * adding function. * Must be called with lr_lock held. */ void ldlm_add_ast_work_item(struct ldlm_lock *lock, struct ldlm_lock *new, struct list_head *work_list) { ENTRY; check_res_locked(lock->l_resource); if (new) ldlm_add_bl_work_item(lock, new, work_list); else ldlm_add_cp_work_item(lock, work_list); EXIT; } /** * Add specified reader/writer reference to LDLM lock with handle \a lockh. * r/w reference type is determined by \a mode * Calls ldlm_lock_addref_internal. */ void ldlm_lock_addref(struct lustre_handle *lockh, enum ldlm_mode mode) { struct ldlm_lock *lock; lock = ldlm_handle2lock(lockh); LASSERTF(lock != NULL, "Non-existing lock: "LPX64"\n", lockh->cookie); ldlm_lock_addref_internal(lock, mode); LDLM_LOCK_PUT(lock); } EXPORT_SYMBOL(ldlm_lock_addref); /** * Helper function. * Add specified reader/writer reference to LDLM lock \a lock. * r/w reference type is determined by \a mode * Removes lock from LRU if it is there. * Assumes the LDLM lock is already locked. */ void ldlm_lock_addref_internal_nolock(struct ldlm_lock *lock, enum ldlm_mode mode) { ldlm_lock_remove_from_lru(lock); if (mode & (LCK_NL | LCK_CR | LCK_PR)) { lock->l_readers++; lu_ref_add_atomic(&lock->l_reference, "reader", lock); } if (mode & (LCK_EX | LCK_CW | LCK_PW | LCK_GROUP | LCK_COS)) { lock->l_writers++; lu_ref_add_atomic(&lock->l_reference, "writer", lock); } LDLM_LOCK_GET(lock); lu_ref_add_atomic(&lock->l_reference, "user", lock); LDLM_DEBUG(lock, "ldlm_lock_addref(%s)", ldlm_lockname[mode]); } /** * Attempts to add reader/writer reference to a lock with handle \a lockh, and * fails if lock is already LDLM_FL_CBPENDING or destroyed. * * \retval 0 success, lock was addref-ed * * \retval -EAGAIN lock is being canceled. */ int ldlm_lock_addref_try(struct lustre_handle *lockh, enum ldlm_mode mode) { struct ldlm_lock *lock; int result; result = -EAGAIN; lock = ldlm_handle2lock(lockh); if (lock != NULL) { lock_res_and_lock(lock); if (lock->l_readers != 0 || lock->l_writers != 0 || !ldlm_is_cbpending(lock)) { ldlm_lock_addref_internal_nolock(lock, mode); result = 0; } unlock_res_and_lock(lock); LDLM_LOCK_PUT(lock); } return result; } EXPORT_SYMBOL(ldlm_lock_addref_try); /** * Add specified reader/writer reference to LDLM lock \a lock. * Locks LDLM lock and calls ldlm_lock_addref_internal_nolock to do the work. * Only called for local locks. */ void ldlm_lock_addref_internal(struct ldlm_lock *lock, enum ldlm_mode mode) { lock_res_and_lock(lock); ldlm_lock_addref_internal_nolock(lock, mode); unlock_res_and_lock(lock); } /** * Removes reader/writer reference for LDLM lock \a lock. * Assumes LDLM lock is already locked. * only called in ldlm_flock_destroy and for local locks. * Does NOT add lock to LRU if no r/w references left to accomodate flock locks * that cannot be placed in LRU. */ void ldlm_lock_decref_internal_nolock(struct ldlm_lock *lock, enum ldlm_mode mode) { LDLM_DEBUG(lock, "ldlm_lock_decref(%s)", ldlm_lockname[mode]); if (mode & (LCK_NL | LCK_CR | LCK_PR)) { LASSERT(lock->l_readers > 0); lu_ref_del(&lock->l_reference, "reader", lock); lock->l_readers--; } if (mode & (LCK_EX | LCK_CW | LCK_PW | LCK_GROUP | LCK_COS)) { LASSERT(lock->l_writers > 0); lu_ref_del(&lock->l_reference, "writer", lock); lock->l_writers--; } lu_ref_del(&lock->l_reference, "user", lock); LDLM_LOCK_RELEASE(lock); /* matches the LDLM_LOCK_GET() in addref */ } /** * Removes reader/writer reference for LDLM lock \a lock. * Locks LDLM lock first. * If the lock is determined to be client lock on a client and r/w refcount * drops to zero and the lock is not blocked, the lock is added to LRU lock * on the namespace. * For blocked LDLM locks if r/w count drops to zero, blocking_ast is called. */ void ldlm_lock_decref_internal(struct ldlm_lock *lock, enum ldlm_mode mode) { struct ldlm_namespace *ns; ENTRY; lock_res_and_lock(lock); ns = ldlm_lock_to_ns(lock); ldlm_lock_decref_internal_nolock(lock, mode); if ((ldlm_is_local(lock) || lock->l_req_mode == LCK_GROUP) && !lock->l_readers && !lock->l_writers) { /* If this is a local lock on a server namespace and this was * the last reference, cancel the lock. * * Group locks are special: * They must not go in LRU, but they are not called back * like non-group locks, instead they are manually released. * They have an l_writers reference which they keep until * they are manually released, so we remove them when they have * no more reader or writer references. - LU-6368 */ ldlm_set_cbpending(lock); } if (!lock->l_readers && !lock->l_writers && ldlm_is_cbpending(lock)) { /* If we received a blocked AST and this was the last reference, * run the callback. */ if (ldlm_is_ns_srv(lock) && lock->l_export) CERROR("FL_CBPENDING set on non-local lock--just a " "warning\n"); LDLM_DEBUG(lock, "final decref done on cbpending lock"); LDLM_LOCK_GET(lock); /* dropped by bl thread */ ldlm_lock_remove_from_lru(lock); unlock_res_and_lock(lock); if (ldlm_is_fail_loc(lock)) OBD_RACE(OBD_FAIL_LDLM_CP_BL_RACE); if (ldlm_is_atomic_cb(lock) || ldlm_bl_to_thread_lock(ns, NULL, lock) != 0) ldlm_handle_bl_callback(ns, NULL, lock); } else if (ns_is_client(ns) && !lock->l_readers && !lock->l_writers && !ldlm_is_no_lru(lock) && !ldlm_is_bl_ast(lock)) { LDLM_DEBUG(lock, "add lock into lru list"); /* If this is a client-side namespace and this was the last * reference, put it on the LRU. */ ldlm_lock_add_to_lru(lock); unlock_res_and_lock(lock); if (ldlm_is_fail_loc(lock)) OBD_RACE(OBD_FAIL_LDLM_CP_BL_RACE); /* Call ldlm_cancel_lru() only if EARLY_CANCEL and LRU RESIZE * are not supported by the server, otherwise, it is done on * enqueue. */ if (!exp_connect_cancelset(lock->l_conn_export) && !ns_connect_lru_resize(ns)) ldlm_cancel_lru(ns, 0, LCF_ASYNC, 0); } else { LDLM_DEBUG(lock, "do not add lock into lru list"); unlock_res_and_lock(lock); } EXIT; } /** * Decrease reader/writer refcount for LDLM lock with handle \a lockh */ void ldlm_lock_decref(struct lustre_handle *lockh, enum ldlm_mode mode) { struct ldlm_lock *lock = __ldlm_handle2lock(lockh, 0); LASSERTF(lock != NULL, "Non-existing lock: "LPX64"\n", lockh->cookie); ldlm_lock_decref_internal(lock, mode); LDLM_LOCK_PUT(lock); } EXPORT_SYMBOL(ldlm_lock_decref); /** * Decrease reader/writer refcount for LDLM lock with handle * \a lockh and mark it for subsequent cancellation once r/w refcount * drops to zero instead of putting into LRU. * */ void ldlm_lock_decref_and_cancel(struct lustre_handle *lockh, enum ldlm_mode mode) { struct ldlm_lock *lock = __ldlm_handle2lock(lockh, 0); ENTRY; LASSERT(lock != NULL); LDLM_DEBUG(lock, "ldlm_lock_decref(%s)", ldlm_lockname[mode]); lock_res_and_lock(lock); ldlm_set_cbpending(lock); unlock_res_and_lock(lock); ldlm_lock_decref_internal(lock, mode); LDLM_LOCK_PUT(lock); } EXPORT_SYMBOL(ldlm_lock_decref_and_cancel); struct sl_insert_point { struct list_head *res_link; struct list_head *mode_link; struct list_head *policy_link; }; /** * Finds a position to insert the new lock into granted lock list. * * Used for locks eligible for skiplist optimization. * * Parameters: * queue [input]: the granted list where search acts on; * req [input]: the lock whose position to be located; * prev [output]: positions within 3 lists to insert @req to * Return Value: * filled @prev * NOTE: called by * - ldlm_grant_lock_with_skiplist */ static void search_granted_lock(struct list_head *queue, struct ldlm_lock *req, struct sl_insert_point *prev) { struct list_head *tmp; struct ldlm_lock *lock, *mode_end, *policy_end; ENTRY; list_for_each(tmp, queue) { lock = list_entry(tmp, struct ldlm_lock, l_res_link); mode_end = list_entry(lock->l_sl_mode.prev, struct ldlm_lock, l_sl_mode); if (lock->l_req_mode != req->l_req_mode) { /* jump to last lock of mode group */ tmp = &mode_end->l_res_link; continue; } /* suitable mode group is found */ if (lock->l_resource->lr_type == LDLM_PLAIN) { /* insert point is last lock of the mode group */ prev->res_link = &mode_end->l_res_link; prev->mode_link = &mode_end->l_sl_mode; prev->policy_link = &req->l_sl_policy; EXIT; return; } else if (lock->l_resource->lr_type == LDLM_IBITS) { for (;;) { policy_end = list_entry(lock->l_sl_policy.prev, struct ldlm_lock, l_sl_policy); if (lock->l_policy_data.l_inodebits.bits == req->l_policy_data.l_inodebits.bits) { /* insert point is last lock of * the policy group */ prev->res_link = &policy_end->l_res_link; prev->mode_link = &policy_end->l_sl_mode; prev->policy_link = &policy_end->l_sl_policy; EXIT; return; } if (policy_end == mode_end) /* done with mode group */ break; /* go to next policy group within mode group */ tmp = policy_end->l_res_link.next; lock = list_entry(tmp, struct ldlm_lock, l_res_link); } /* loop over policy groups within the mode group */ /* insert point is last lock of the mode group, * new policy group is started */ prev->res_link = &mode_end->l_res_link; prev->mode_link = &mode_end->l_sl_mode; prev->policy_link = &req->l_sl_policy; EXIT; return; } else { LDLM_ERROR(lock,"is not LDLM_PLAIN or LDLM_IBITS lock"); LBUG(); } } /* insert point is last lock on the queue, * new mode group and new policy group are started */ prev->res_link = queue->prev; prev->mode_link = &req->l_sl_mode; prev->policy_link = &req->l_sl_policy; EXIT; return; } /** * Add a lock into resource granted list after a position described by * \a prev. */ static void ldlm_granted_list_add_lock(struct ldlm_lock *lock, struct sl_insert_point *prev) { struct ldlm_resource *res = lock->l_resource; ENTRY; check_res_locked(res); ldlm_resource_dump(D_INFO, res); LDLM_DEBUG(lock, "About to add lock:"); if (ldlm_is_destroyed(lock)) { CDEBUG(D_OTHER, "Lock destroyed, not adding to resource\n"); return; } LASSERT(list_empty(&lock->l_res_link)); LASSERT(list_empty(&lock->l_sl_mode)); LASSERT(list_empty(&lock->l_sl_policy)); /* * lock->link == prev->link means lock is first starting the group. * Don't re-add to itself to suppress kernel warnings. */ if (&lock->l_res_link != prev->res_link) list_add(&lock->l_res_link, prev->res_link); if (&lock->l_sl_mode != prev->mode_link) list_add(&lock->l_sl_mode, prev->mode_link); if (&lock->l_sl_policy != prev->policy_link) list_add(&lock->l_sl_policy, prev->policy_link); EXIT; } /** * Add a lock to granted list on a resource maintaining skiplist * correctness. */ static void ldlm_grant_lock_with_skiplist(struct ldlm_lock *lock) { struct sl_insert_point prev; ENTRY; LASSERT(lock->l_req_mode == lock->l_granted_mode); search_granted_lock(&lock->l_resource->lr_granted, lock, &prev); ldlm_granted_list_add_lock(lock, &prev); EXIT; } /** * Perform lock granting bookkeeping. * * Includes putting the lock into granted list and updating lock mode. * NOTE: called by * - ldlm_lock_enqueue * - ldlm_reprocess_queue * - ldlm_lock_convert * * must be called with lr_lock held */ void ldlm_grant_lock(struct ldlm_lock *lock, struct list_head *work_list) { struct ldlm_resource *res = lock->l_resource; ENTRY; check_res_locked(res); lock->l_granted_mode = lock->l_req_mode; if (work_list && lock->l_completion_ast != NULL) ldlm_add_ast_work_item(lock, NULL, work_list); /* We should not add locks to granted list in the following cases: * - this is an UNLOCK but not a real lock; * - this is a TEST lock; * - this is a F_CANCELLK lock (async flock has req_mode == 0) * - this is a deadlock (flock cannot be granted) */ if (lock->l_req_mode == 0 || lock->l_req_mode == LCK_NL || ldlm_is_test_lock(lock) || ldlm_is_flock_deadlock(lock)) RETURN_EXIT; if (res->lr_type == LDLM_PLAIN || res->lr_type == LDLM_IBITS) ldlm_grant_lock_with_skiplist(lock); else if (res->lr_type == LDLM_EXTENT) ldlm_extent_add_lock(res, lock); else ldlm_resource_add_lock(res, &res->lr_granted, lock); ldlm_pool_add(&ldlm_res_to_ns(res)->ns_pool, lock); EXIT; } /** * Describe the overlap between two locks. itree_overlap_cb data. */ struct lock_match_data { struct ldlm_lock *lmd_old; struct ldlm_lock *lmd_lock; enum ldlm_mode *lmd_mode; union ldlm_policy_data *lmd_policy; __u64 lmd_flags; int lmd_unref; }; /** * Check if the given @lock meets the criteria for a match. * A reference on the lock is taken if matched. * * \param lock test-against this lock * \param data parameters */ static int lock_matches(struct ldlm_lock *lock, struct lock_match_data *data) { union ldlm_policy_data *lpol = &lock->l_policy_data; enum ldlm_mode match; if (lock == data->lmd_old) return INTERVAL_ITER_STOP; /* Check if this lock can be matched. * Used by LU-2919(exclusive open) for open lease lock */ if (ldlm_is_excl(lock)) return INTERVAL_ITER_CONT; /* llite sometimes wants to match locks that will be * canceled when their users drop, but we allow it to match * if it passes in CBPENDING and the lock still has users. * this is generally only going to be used by children * whose parents already hold a lock so forward progress * can still happen. */ if (ldlm_is_cbpending(lock) && !(data->lmd_flags & LDLM_FL_CBPENDING)) return INTERVAL_ITER_CONT; if (!data->lmd_unref && ldlm_is_cbpending(lock) && lock->l_readers == 0 && lock->l_writers == 0) return INTERVAL_ITER_CONT; if (!(lock->l_req_mode & *data->lmd_mode)) return INTERVAL_ITER_CONT; match = lock->l_req_mode; switch (lock->l_resource->lr_type) { case LDLM_EXTENT: if (lpol->l_extent.start > data->lmd_policy->l_extent.start || lpol->l_extent.end < data->lmd_policy->l_extent.end) return INTERVAL_ITER_CONT; if (unlikely(match == LCK_GROUP) && data->lmd_policy->l_extent.gid != LDLM_GID_ANY && lpol->l_extent.gid != data->lmd_policy->l_extent.gid) return INTERVAL_ITER_CONT; break; case LDLM_IBITS: /* We match if we have existing lock with same or wider set of bits. */ if ((lpol->l_inodebits.bits & data->lmd_policy->l_inodebits.bits) != data->lmd_policy->l_inodebits.bits) return INTERVAL_ITER_CONT; break; default: ; } /* We match if we have existing lock with same or wider set of bits. */ if (!data->lmd_unref && LDLM_HAVE_MASK(lock, GONE)) return INTERVAL_ITER_CONT; if (!equi(data->lmd_flags & LDLM_FL_LOCAL_ONLY, ldlm_is_local(lock))) return INTERVAL_ITER_CONT; if (data->lmd_flags & LDLM_FL_TEST_LOCK) { LDLM_LOCK_GET(lock); ldlm_lock_touch_in_lru(lock); } else { ldlm_lock_addref_internal_nolock(lock, match); } *data->lmd_mode = match; data->lmd_lock = lock; return INTERVAL_ITER_STOP; } static unsigned int itree_overlap_cb(struct interval_node *in, void *args) { struct ldlm_interval *node = to_ldlm_interval(in); struct lock_match_data *data = args; struct ldlm_lock *lock; int rc; list_for_each_entry(lock, &node->li_group, l_sl_policy) { rc = lock_matches(lock, data); if (rc == INTERVAL_ITER_STOP) return INTERVAL_ITER_STOP; } return INTERVAL_ITER_CONT; } /** * Search for a lock with given parameters in interval trees. * * \param res search for a lock in this resource * \param data parameters * * \retval a referenced lock or NULL. */ static struct ldlm_lock *search_itree(struct ldlm_resource *res, struct lock_match_data *data) { struct interval_node_extent ext = { .start = data->lmd_policy->l_extent.start, .end = data->lmd_policy->l_extent.end }; int idx; for (idx = 0; idx < LCK_MODE_NUM; idx++) { struct ldlm_interval_tree *tree = &res->lr_itree[idx]; if (tree->lit_root == NULL) continue; if (!(tree->lit_mode & *data->lmd_mode)) continue; interval_search(tree->lit_root, &ext, itree_overlap_cb, data); } return data->lmd_lock; } /** * Search for a lock with given properties in a queue. * * \param queue search for a lock in this queue * \param data parameters * * \retval a referenced lock or NULL. */ static struct ldlm_lock *search_queue(struct list_head *queue, struct lock_match_data *data) { struct ldlm_lock *lock; int rc; list_for_each_entry(lock, queue, l_res_link) { rc = lock_matches(lock, data); if (rc == INTERVAL_ITER_STOP) return data->lmd_lock; } return NULL; } void ldlm_lock_fail_match_locked(struct ldlm_lock *lock) { if ((lock->l_flags & LDLM_FL_FAIL_NOTIFIED) == 0) { lock->l_flags |= LDLM_FL_FAIL_NOTIFIED; wake_up_all(&lock->l_waitq); } } EXPORT_SYMBOL(ldlm_lock_fail_match_locked); void ldlm_lock_fail_match(struct ldlm_lock *lock) { lock_res_and_lock(lock); ldlm_lock_fail_match_locked(lock); unlock_res_and_lock(lock); } /** * Mark lock as "matchable" by OST. * * Used to prevent certain races in LOV/OSC where the lock is granted, but LVB * is not yet valid. * Assumes LDLM lock is already locked. */ void ldlm_lock_allow_match_locked(struct ldlm_lock *lock) { ldlm_set_lvb_ready(lock); wake_up_all(&lock->l_waitq); } EXPORT_SYMBOL(ldlm_lock_allow_match_locked); /** * Mark lock as "matchable" by OST. * Locks the lock and then \see ldlm_lock_allow_match_locked */ void ldlm_lock_allow_match(struct ldlm_lock *lock) { lock_res_and_lock(lock); ldlm_lock_allow_match_locked(lock); unlock_res_and_lock(lock); } EXPORT_SYMBOL(ldlm_lock_allow_match); /** * Attempt to find a lock with specified properties. * * Typically returns a reference to matched lock unless LDLM_FL_TEST_LOCK is * set in \a flags * * Can be called in two ways: * * If 'ns' is NULL, then lockh describes an existing lock that we want to look * for a duplicate of. * * Otherwise, all of the fields must be filled in, to match against. * * If 'flags' contains LDLM_FL_LOCAL_ONLY, then only match local locks on the * server (ie, connh is NULL) * If 'flags' contains LDLM_FL_BLOCK_GRANTED, then only locks on the granted * list will be considered * If 'flags' contains LDLM_FL_CBPENDING, then locks that have been marked * to be canceled can still be matched as long as they still have reader * or writer refernces * If 'flags' contains LDLM_FL_TEST_LOCK, then don't actually reference a lock, * just tell us if we would have matched. * * \retval 1 if it finds an already-existing lock that is compatible; in this * case, lockh is filled in with a addref()ed lock * * We also check security context, and if that fails we simply return 0 (to * keep caller code unchanged), the context failure will be discovered by * caller sometime later. */ enum ldlm_mode ldlm_lock_match(struct ldlm_namespace *ns, __u64 flags, const struct ldlm_res_id *res_id, enum ldlm_type type, union ldlm_policy_data *policy, enum ldlm_mode mode, struct lustre_handle *lockh, int unref) { struct lock_match_data data = { .lmd_old = NULL, .lmd_lock = NULL, .lmd_mode = &mode, .lmd_policy = policy, .lmd_flags = flags, .lmd_unref = unref, }; struct ldlm_resource *res; struct ldlm_lock *lock; int rc = 0; ENTRY; if (ns == NULL) { data.lmd_old = ldlm_handle2lock(lockh); LASSERT(data.lmd_old != NULL); ns = ldlm_lock_to_ns(data.lmd_old); res_id = &data.lmd_old->l_resource->lr_name; type = data.lmd_old->l_resource->lr_type; *data.lmd_mode = data.lmd_old->l_req_mode; } res = ldlm_resource_get(ns, NULL, res_id, type, 0); if (IS_ERR(res)) { LASSERT(data.lmd_old == NULL); RETURN(0); } LDLM_RESOURCE_ADDREF(res); lock_res(res); if (res->lr_type == LDLM_EXTENT) lock = search_itree(res, &data); else lock = search_queue(&res->lr_granted, &data); if (lock != NULL) GOTO(out, rc = 1); if (flags & LDLM_FL_BLOCK_GRANTED) GOTO(out, rc = 0); lock = search_queue(&res->lr_converting, &data); if (lock != NULL) GOTO(out, rc = 1); lock = search_queue(&res->lr_waiting, &data); if (lock != NULL) GOTO(out, rc = 1); EXIT; out: unlock_res(res); LDLM_RESOURCE_DELREF(res); ldlm_resource_putref(res); if (lock) { ldlm_lock2handle(lock, lockh); if ((flags & LDLM_FL_LVB_READY) && (!ldlm_is_lvb_ready(lock))) { __u64 wait_flags = LDLM_FL_LVB_READY | LDLM_FL_DESTROYED | LDLM_FL_FAIL_NOTIFIED; struct l_wait_info lwi; if (lock->l_completion_ast) { int err = lock->l_completion_ast(lock, LDLM_FL_WAIT_NOREPROC, NULL); if (err) { if (flags & LDLM_FL_TEST_LOCK) LDLM_LOCK_RELEASE(lock); else ldlm_lock_decref_internal(lock, mode); rc = 0; goto out2; } } lwi = LWI_TIMEOUT_INTR(cfs_time_seconds(obd_timeout), NULL, LWI_ON_SIGNAL_NOOP, NULL); /* XXX FIXME see comment on CAN_MATCH in lustre_dlm.h */ l_wait_event(lock->l_waitq, lock->l_flags & wait_flags, &lwi); if (!ldlm_is_lvb_ready(lock)) { if (flags & LDLM_FL_TEST_LOCK) LDLM_LOCK_RELEASE(lock); else ldlm_lock_decref_internal(lock, mode); rc = 0; } } } out2: if (rc) { LDLM_DEBUG(lock, "matched ("LPU64" "LPU64")", (type == LDLM_PLAIN || type == LDLM_IBITS) ? res_id->name[2] : policy->l_extent.start, (type == LDLM_PLAIN || type == LDLM_IBITS) ? res_id->name[3] : policy->l_extent.end); /* check user's security context */ if (lock->l_conn_export && sptlrpc_import_check_ctx( class_exp2cliimp(lock->l_conn_export))) { if (!(flags & LDLM_FL_TEST_LOCK)) ldlm_lock_decref_internal(lock, mode); rc = 0; } if (flags & LDLM_FL_TEST_LOCK) LDLM_LOCK_RELEASE(lock); } else if (!(flags & LDLM_FL_TEST_LOCK)) {/*less verbose for test-only*/ LDLM_DEBUG_NOLOCK("not matched ns %p type %u mode %u res " LPU64"/"LPU64" ("LPU64" "LPU64")", ns, type, mode, res_id->name[0], res_id->name[1], (type == LDLM_PLAIN || type == LDLM_IBITS) ? res_id->name[2] :policy->l_extent.start, (type == LDLM_PLAIN || type == LDLM_IBITS) ? res_id->name[3] : policy->l_extent.end); } if (data.lmd_old != NULL) LDLM_LOCK_PUT(data.lmd_old); return rc ? mode : 0; } EXPORT_SYMBOL(ldlm_lock_match); enum ldlm_mode ldlm_revalidate_lock_handle(struct lustre_handle *lockh, __u64 *bits) { struct ldlm_lock *lock; enum ldlm_mode mode = 0; ENTRY; lock = ldlm_handle2lock(lockh); if (lock != NULL) { lock_res_and_lock(lock); if (LDLM_HAVE_MASK(lock, GONE)) GOTO(out, mode); if (ldlm_is_cbpending(lock) && lock->l_readers == 0 && lock->l_writers == 0) GOTO(out, mode); if (bits) *bits = lock->l_policy_data.l_inodebits.bits; mode = lock->l_granted_mode; ldlm_lock_addref_internal_nolock(lock, mode); } EXIT; out: if (lock != NULL) { unlock_res_and_lock(lock); LDLM_LOCK_PUT(lock); } return mode; } EXPORT_SYMBOL(ldlm_revalidate_lock_handle); /** The caller must guarantee that the buffer is large enough. */ int ldlm_fill_lvb(struct ldlm_lock *lock, struct req_capsule *pill, enum req_location loc, void *data, int size) { void *lvb; ENTRY; LASSERT(data != NULL); LASSERT(size >= 0); switch (lock->l_lvb_type) { case LVB_T_OST: if (size == sizeof(struct ost_lvb)) { if (loc == RCL_CLIENT) lvb = req_capsule_client_swab_get(pill, &RMF_DLM_LVB, lustre_swab_ost_lvb); else lvb = req_capsule_server_swab_get(pill, &RMF_DLM_LVB, lustre_swab_ost_lvb); if (unlikely(lvb == NULL)) { LDLM_ERROR(lock, "no LVB"); RETURN(-EPROTO); } memcpy(data, lvb, size); } else if (size == sizeof(struct ost_lvb_v1)) { struct ost_lvb *olvb = data; if (loc == RCL_CLIENT) lvb = req_capsule_client_swab_get(pill, &RMF_DLM_LVB, lustre_swab_ost_lvb_v1); else lvb = req_capsule_server_sized_swab_get(pill, &RMF_DLM_LVB, size, lustre_swab_ost_lvb_v1); if (unlikely(lvb == NULL)) { LDLM_ERROR(lock, "no LVB"); RETURN(-EPROTO); } memcpy(data, lvb, size); olvb->lvb_mtime_ns = 0; olvb->lvb_atime_ns = 0; olvb->lvb_ctime_ns = 0; } else { LDLM_ERROR(lock, "Replied unexpected ost LVB size %d", size); RETURN(-EINVAL); } break; case LVB_T_LQUOTA: if (size == sizeof(struct lquota_lvb)) { if (loc == RCL_CLIENT) lvb = req_capsule_client_swab_get(pill, &RMF_DLM_LVB, lustre_swab_lquota_lvb); else lvb = req_capsule_server_swab_get(pill, &RMF_DLM_LVB, lustre_swab_lquota_lvb); if (unlikely(lvb == NULL)) { LDLM_ERROR(lock, "no LVB"); RETURN(-EPROTO); } memcpy(data, lvb, size); } else { LDLM_ERROR(lock, "Replied unexpected lquota LVB size %d", size); RETURN(-EINVAL); } break; case LVB_T_LAYOUT: if (size == 0) break; if (loc == RCL_CLIENT) lvb = req_capsule_client_get(pill, &RMF_DLM_LVB); else lvb = req_capsule_server_get(pill, &RMF_DLM_LVB); if (unlikely(lvb == NULL)) { LDLM_ERROR(lock, "no LVB"); RETURN(-EPROTO); } memcpy(data, lvb, size); break; default: LDLM_ERROR(lock, "Unknown LVB type: %d\n", lock->l_lvb_type); libcfs_debug_dumpstack(NULL); RETURN(-EINVAL); } RETURN(0); } /** * Create and fill in new LDLM lock with specified properties. * Returns a referenced lock */ struct ldlm_lock *ldlm_lock_create(struct ldlm_namespace *ns, const struct ldlm_res_id *res_id, enum ldlm_type type, enum ldlm_mode mode, const struct ldlm_callback_suite *cbs, void *data, __u32 lvb_len, enum lvb_type lvb_type) { struct ldlm_lock *lock; struct ldlm_resource *res; int rc; ENTRY; res = ldlm_resource_get(ns, NULL, res_id, type, 1); if (IS_ERR(res)) RETURN(ERR_CAST(res)); lock = ldlm_lock_new(res); if (lock == NULL) RETURN(ERR_PTR(-ENOMEM)); lock->l_req_mode = mode; lock->l_ast_data = data; lock->l_pid = current_pid(); if (ns_is_server(ns)) ldlm_set_ns_srv(lock); if (cbs) { lock->l_blocking_ast = cbs->lcs_blocking; lock->l_completion_ast = cbs->lcs_completion; lock->l_glimpse_ast = cbs->lcs_glimpse; } lock->l_tree_node = NULL; /* if this is the extent lock, allocate the interval tree node */ if (type == LDLM_EXTENT) if (ldlm_interval_alloc(lock) == NULL) GOTO(out, rc = -ENOMEM); if (lvb_len) { lock->l_lvb_len = lvb_len; OBD_ALLOC_LARGE(lock->l_lvb_data, lvb_len); if (lock->l_lvb_data == NULL) GOTO(out, rc = -ENOMEM); } lock->l_lvb_type = lvb_type; if (OBD_FAIL_CHECK(OBD_FAIL_LDLM_NEW_LOCK)) GOTO(out, rc = -ENOENT); RETURN(lock); out: ldlm_lock_destroy(lock); LDLM_LOCK_RELEASE(lock); RETURN(ERR_PTR(rc)); } /** * Enqueue (request) a lock. * * Does not block. As a result of enqueue the lock would be put * into granted or waiting list. * * If namespace has intent policy sent and the lock has LDLM_FL_HAS_INTENT flag * set, skip all the enqueueing and delegate lock processing to intent policy * function. */ enum ldlm_error ldlm_lock_enqueue(struct ldlm_namespace *ns, struct ldlm_lock **lockp, void *cookie, __u64 *flags) { struct ldlm_lock *lock = *lockp; struct ldlm_resource *res = lock->l_resource; int local = ns_is_client(ldlm_res_to_ns(res)); #ifdef HAVE_SERVER_SUPPORT ldlm_processing_policy policy; #endif enum ldlm_error rc = ELDLM_OK; struct ldlm_interval *node = NULL; ENTRY; /* policies are not executed on the client or during replay */ if ((*flags & (LDLM_FL_HAS_INTENT|LDLM_FL_REPLAY)) == LDLM_FL_HAS_INTENT && !local && ns->ns_policy) { rc = ns->ns_policy(ns, lockp, cookie, lock->l_req_mode, *flags, NULL); if (rc == ELDLM_LOCK_REPLACED) { /* The lock that was returned has already been granted, * and placed into lockp. If it's not the same as the * one we passed in, then destroy the old one and our * work here is done. */ if (lock != *lockp) { ldlm_lock_destroy(lock); LDLM_LOCK_RELEASE(lock); } *flags |= LDLM_FL_LOCK_CHANGED; RETURN(0); } else if (rc != ELDLM_OK || (rc == ELDLM_OK && (*flags & LDLM_FL_INTENT_ONLY))) { ldlm_lock_destroy(lock); RETURN(rc); } } if (*flags & LDLM_FL_RESENT) { /* Reconstruct LDLM_FL_SRV_ENQ_MASK @flags for reply. * Set LOCK_CHANGED always. * Check if the lock is granted for BLOCK_GRANTED. * Take NO_TIMEOUT from the lock as it is inherited through * LDLM_FL_INHERIT_MASK */ *flags |= LDLM_FL_LOCK_CHANGED; if (lock->l_req_mode != lock->l_granted_mode) *flags |= LDLM_FL_BLOCK_GRANTED; *flags |= lock->l_flags & LDLM_FL_NO_TIMEOUT; RETURN(ELDLM_OK); } /* For a replaying lock, it might be already in granted list. So * unlinking the lock will cause the interval node to be freed, we * have to allocate the interval node early otherwise we can't regrant * this lock in the future. - jay */ if (!local && (*flags & LDLM_FL_REPLAY) && res->lr_type == LDLM_EXTENT) OBD_SLAB_ALLOC_PTR_GFP(node, ldlm_interval_slab, GFP_NOFS); lock_res_and_lock(lock); if (local && lock->l_req_mode == lock->l_granted_mode) { /* The server returned a blocked lock, but it was granted * before we got a chance to actually enqueue it. We don't * need to do anything else. */ *flags &= ~LDLM_FL_BLOCKED_MASK; GOTO(out, rc = ELDLM_OK); } ldlm_resource_unlink_lock(lock); if (res->lr_type == LDLM_EXTENT && lock->l_tree_node == NULL) { if (node == NULL) { ldlm_lock_destroy_nolock(lock); GOTO(out, rc = -ENOMEM); } INIT_LIST_HEAD(&node->li_group); ldlm_interval_attach(node, lock); node = NULL; } /* Some flags from the enqueue want to make it into the AST, via the * lock's l_flags. */ if (*flags & LDLM_FL_AST_DISCARD_DATA) ldlm_set_ast_discard_data(lock); if (*flags & LDLM_FL_TEST_LOCK) ldlm_set_test_lock(lock); /* This distinction between local lock trees is very important; a client * namespace only has information about locks taken by that client, and * thus doesn't have enough information to decide for itself if it can * be granted (below). In this case, we do exactly what the server * tells us to do, as dictated by the 'flags'. * * We do exactly the same thing during recovery, when the server is * more or less trusting the clients not to lie. * * FIXME (bug 268): Detect obvious lies by checking compatibility in * granted/converting queues. */ if (local) { if (*flags & LDLM_FL_BLOCK_CONV) ldlm_resource_add_lock(res, &res->lr_converting, lock); else if (*flags & (LDLM_FL_BLOCK_WAIT | LDLM_FL_BLOCK_GRANTED)) ldlm_resource_add_lock(res, &res->lr_waiting, lock); else ldlm_grant_lock(lock, NULL); GOTO(out, rc = ELDLM_OK); #ifdef HAVE_SERVER_SUPPORT } else if (*flags & LDLM_FL_REPLAY) { if (*flags & LDLM_FL_BLOCK_CONV) { ldlm_resource_add_lock(res, &res->lr_converting, lock); GOTO(out, rc = ELDLM_OK); } else if (*flags & LDLM_FL_BLOCK_WAIT) { ldlm_resource_add_lock(res, &res->lr_waiting, lock); GOTO(out, rc = ELDLM_OK); } else if (*flags & LDLM_FL_BLOCK_GRANTED) { ldlm_grant_lock(lock, NULL); GOTO(out, rc = ELDLM_OK); } /* If no flags, fall through to normal enqueue path. */ } policy = ldlm_processing_policy_table[res->lr_type]; policy(lock, flags, 1, &rc, NULL); GOTO(out, rc); #else } else { CERROR("This is client-side-only module, cannot handle " "LDLM_NAMESPACE_SERVER resource type lock.\n"); LBUG(); } #endif out: unlock_res_and_lock(lock); if (node) OBD_SLAB_FREE(node, ldlm_interval_slab, sizeof(*node)); return rc; } #ifdef HAVE_SERVER_SUPPORT /** * Iterate through all waiting locks on a given resource queue and attempt to * grant them. * * Must be called with resource lock held. */ int ldlm_reprocess_queue(struct ldlm_resource *res, struct list_head *queue, struct list_head *work_list) { struct list_head *tmp, *pos; ldlm_processing_policy policy; __u64 flags; int rc = LDLM_ITER_CONTINUE; enum ldlm_error err; ENTRY; check_res_locked(res); policy = ldlm_processing_policy_table[res->lr_type]; LASSERT(policy); list_for_each_safe(tmp, pos, queue) { struct ldlm_lock *pending; pending = list_entry(tmp, struct ldlm_lock, l_res_link); CDEBUG(D_INFO, "Reprocessing lock %p\n", pending); flags = 0; rc = policy(pending, &flags, 0, &err, work_list); if (rc != LDLM_ITER_CONTINUE) break; } RETURN(rc); } #endif /** * Process a call to blocking AST callback for a lock in ast_work list */ static int ldlm_work_bl_ast_lock(struct ptlrpc_request_set *rqset, void *opaq) { struct ldlm_cb_set_arg *arg = opaq; struct ldlm_lock_desc d; int rc; struct ldlm_lock *lock; ENTRY; if (list_empty(arg->list)) RETURN(-ENOENT); lock = list_entry(arg->list->next, struct ldlm_lock, l_bl_ast); /* nobody should touch l_bl_ast */ lock_res_and_lock(lock); list_del_init(&lock->l_bl_ast); LASSERT(ldlm_is_ast_sent(lock)); LASSERT(lock->l_bl_ast_run == 0); LASSERT(lock->l_blocking_lock); lock->l_bl_ast_run++; unlock_res_and_lock(lock); ldlm_lock2desc(lock->l_blocking_lock, &d); rc = lock->l_blocking_ast(lock, &d, (void *)arg, LDLM_CB_BLOCKING); LDLM_LOCK_RELEASE(lock->l_blocking_lock); lock->l_blocking_lock = NULL; LDLM_LOCK_RELEASE(lock); RETURN(rc); } /** * Process a call to completion AST callback for a lock in ast_work list */ static int ldlm_work_cp_ast_lock(struct ptlrpc_request_set *rqset, void *opaq) { struct ldlm_cb_set_arg *arg = opaq; int rc = 0; struct ldlm_lock *lock; ldlm_completion_callback completion_callback; ENTRY; if (list_empty(arg->list)) RETURN(-ENOENT); lock = list_entry(arg->list->next, struct ldlm_lock, l_cp_ast); /* It's possible to receive a completion AST before we've set * the l_completion_ast pointer: either because the AST arrived * before the reply, or simply because there's a small race * window between receiving the reply and finishing the local * enqueue. (bug 842) * * This can't happen with the blocking_ast, however, because we * will never call the local blocking_ast until we drop our * reader/writer reference, which we won't do until we get the * reply and finish enqueueing. */ /* nobody should touch l_cp_ast */ lock_res_and_lock(lock); list_del_init(&lock->l_cp_ast); LASSERT(ldlm_is_cp_reqd(lock)); /* save l_completion_ast since it can be changed by * mds_intent_policy(), see bug 14225 */ completion_callback = lock->l_completion_ast; ldlm_clear_cp_reqd(lock); unlock_res_and_lock(lock); if (completion_callback != NULL) rc = completion_callback(lock, 0, (void *)arg); LDLM_LOCK_RELEASE(lock); RETURN(rc); } /** * Process a call to revocation AST callback for a lock in ast_work list */ static int ldlm_work_revoke_ast_lock(struct ptlrpc_request_set *rqset, void *opaq) { struct ldlm_cb_set_arg *arg = opaq; struct ldlm_lock_desc desc; int rc; struct ldlm_lock *lock; ENTRY; if (list_empty(arg->list)) RETURN(-ENOENT); lock = list_entry(arg->list->next, struct ldlm_lock, l_rk_ast); list_del_init(&lock->l_rk_ast); /* the desc just pretend to exclusive */ ldlm_lock2desc(lock, &desc); desc.l_req_mode = LCK_EX; desc.l_granted_mode = 0; rc = lock->l_blocking_ast(lock, &desc, (void*)arg, LDLM_CB_BLOCKING); LDLM_LOCK_RELEASE(lock); RETURN(rc); } /** * Process a call to glimpse AST callback for a lock in ast_work list */ int ldlm_work_gl_ast_lock(struct ptlrpc_request_set *rqset, void *opaq) { struct ldlm_cb_set_arg *arg = opaq; struct ldlm_glimpse_work *gl_work; struct ldlm_lock *lock; int rc = 0; ENTRY; if (list_empty(arg->list)) RETURN(-ENOENT); gl_work = list_entry(arg->list->next, struct ldlm_glimpse_work, gl_list); list_del_init(&gl_work->gl_list); lock = gl_work->gl_lock; /* transfer the glimpse descriptor to ldlm_cb_set_arg */ arg->gl_desc = gl_work->gl_desc; /* invoke the actual glimpse callback */ if (lock->l_glimpse_ast(lock, (void*)arg) == 0) rc = 1; LDLM_LOCK_RELEASE(lock); if ((gl_work->gl_flags & LDLM_GL_WORK_NOFREE) == 0) OBD_FREE_PTR(gl_work); RETURN(rc); } /** * Process list of locks in need of ASTs being sent. * * Used on server to send multiple ASTs together instead of sending one by * one. */ int ldlm_run_ast_work(struct ldlm_namespace *ns, struct list_head *rpc_list, ldlm_desc_ast_t ast_type) { struct ldlm_cb_set_arg *arg; set_producer_func work_ast_lock; int rc; if (list_empty(rpc_list)) RETURN(0); OBD_ALLOC_PTR(arg); if (arg == NULL) RETURN(-ENOMEM); atomic_set(&arg->restart, 0); arg->list = rpc_list; switch (ast_type) { case LDLM_WORK_BL_AST: arg->type = LDLM_BL_CALLBACK; work_ast_lock = ldlm_work_bl_ast_lock; break; case LDLM_WORK_CP_AST: arg->type = LDLM_CP_CALLBACK; work_ast_lock = ldlm_work_cp_ast_lock; break; case LDLM_WORK_REVOKE_AST: arg->type = LDLM_BL_CALLBACK; work_ast_lock = ldlm_work_revoke_ast_lock; break; case LDLM_WORK_GL_AST: arg->type = LDLM_GL_CALLBACK; work_ast_lock = ldlm_work_gl_ast_lock; break; default: LBUG(); } /* We create a ptlrpc request set with flow control extension. * This request set will use the work_ast_lock function to produce new * requests and will send a new request each time one completes in order * to keep the number of requests in flight to ns_max_parallel_ast */ arg->set = ptlrpc_prep_fcset(ns->ns_max_parallel_ast ? : UINT_MAX, work_ast_lock, arg); if (arg->set == NULL) GOTO(out, rc = -ENOMEM); ptlrpc_set_wait(arg->set); ptlrpc_set_destroy(arg->set); rc = atomic_read(&arg->restart) ? -ERESTART : 0; GOTO(out, rc); out: OBD_FREE_PTR(arg); return rc; } static int reprocess_one_queue(struct ldlm_resource *res, void *closure) { ldlm_reprocess_all(res); return LDLM_ITER_CONTINUE; } static int ldlm_reprocess_res(struct cfs_hash *hs, struct cfs_hash_bd *bd, struct hlist_node *hnode, void *arg) { struct ldlm_resource *res = cfs_hash_object(hs, hnode); int rc; rc = reprocess_one_queue(res, arg); return rc == LDLM_ITER_STOP; } /** * Iterate through all resources on a namespace attempting to grant waiting * locks. */ void ldlm_reprocess_all_ns(struct ldlm_namespace *ns) { ENTRY; if (ns != NULL) { cfs_hash_for_each_nolock(ns->ns_rs_hash, ldlm_reprocess_res, NULL, 0); } EXIT; } /** * Try to grant all waiting locks on a resource. * * Calls ldlm_reprocess_queue on converting and waiting queues. * * Typically called after some resource locks are cancelled to see * if anything could be granted as a result of the cancellation. */ void ldlm_reprocess_all(struct ldlm_resource *res) { struct list_head rpc_list; #ifdef HAVE_SERVER_SUPPORT int rc; ENTRY; INIT_LIST_HEAD(&rpc_list); /* Local lock trees don't get reprocessed. */ if (ns_is_client(ldlm_res_to_ns(res))) { EXIT; return; } restart: lock_res(res); rc = ldlm_reprocess_queue(res, &res->lr_converting, &rpc_list); if (rc == LDLM_ITER_CONTINUE) ldlm_reprocess_queue(res, &res->lr_waiting, &rpc_list); unlock_res(res); rc = ldlm_run_ast_work(ldlm_res_to_ns(res), &rpc_list, LDLM_WORK_CP_AST); if (rc == -ERESTART) { LASSERT(list_empty(&rpc_list)); goto restart; } #else ENTRY; INIT_LIST_HEAD(&rpc_list); if (!ns_is_client(ldlm_res_to_ns(res))) { CERROR("This is client-side-only module, cannot handle " "LDLM_NAMESPACE_SERVER resource type lock.\n"); LBUG(); } #endif EXIT; } EXPORT_SYMBOL(ldlm_reprocess_all); static bool is_bl_done(struct ldlm_lock *lock) { bool bl_done = true; if (!ldlm_is_bl_done(lock)) { lock_res_and_lock(lock); bl_done = ldlm_is_bl_done(lock); unlock_res_and_lock(lock); } return bl_done; } /** * Helper function to call blocking AST for LDLM lock \a lock in a * "cancelling" mode. */ void ldlm_cancel_callback(struct ldlm_lock *lock) { check_res_locked(lock->l_resource); if (!ldlm_is_cancel(lock)) { ldlm_set_cancel(lock); if (lock->l_blocking_ast) { unlock_res_and_lock(lock); lock->l_blocking_ast(lock, NULL, lock->l_ast_data, LDLM_CB_CANCELING); lock_res_and_lock(lock); } else { LDLM_DEBUG(lock, "no blocking ast"); } /* only canceller can set bl_done bit */ ldlm_set_bl_done(lock); wake_up_all(&lock->l_waitq); } else if (!ldlm_is_bl_done(lock)) { struct l_wait_info lwi = { 0 }; /* The lock is guaranteed to have been canceled once * returning from this function. */ unlock_res_and_lock(lock); l_wait_event(lock->l_waitq, is_bl_done(lock), &lwi); lock_res_and_lock(lock); } } /** * Remove skiplist-enabled LDLM lock \a req from granted list */ void ldlm_unlink_lock_skiplist(struct ldlm_lock *req) { if (req->l_resource->lr_type != LDLM_PLAIN && req->l_resource->lr_type != LDLM_IBITS) return; list_del_init(&req->l_sl_policy); list_del_init(&req->l_sl_mode); } /** * Attempts to cancel LDLM lock \a lock that has no reader/writer references. */ void ldlm_lock_cancel(struct ldlm_lock *lock) { struct ldlm_resource *res; struct ldlm_namespace *ns; ENTRY; lock_res_and_lock(lock); res = lock->l_resource; ns = ldlm_res_to_ns(res); /* Please do not, no matter how tempting, remove this LBUG without * talking to me first. -phik */ if (lock->l_readers || lock->l_writers) { LDLM_ERROR(lock, "lock still has references"); LBUG(); } if (ldlm_is_waited(lock)) ldlm_del_waiting_lock(lock); /* Releases cancel callback. */ ldlm_cancel_callback(lock); LASSERT(!ldlm_is_waited(lock)); ldlm_resource_unlink_lock(lock); ldlm_lock_destroy_nolock(lock); if (lock->l_granted_mode == lock->l_req_mode) ldlm_pool_del(&ns->ns_pool, lock); /* Make sure we will not be called again for same lock what is possible * if not to zero out lock->l_granted_mode */ lock->l_granted_mode = LCK_MINMODE; unlock_res_and_lock(lock); EXIT; } EXPORT_SYMBOL(ldlm_lock_cancel); /** * Set opaque data into the lock that only makes sense to upper layer. */ int ldlm_lock_set_data(struct lustre_handle *lockh, void *data) { struct ldlm_lock *lock = ldlm_handle2lock(lockh); int rc = -EINVAL; ENTRY; if (lock) { if (lock->l_ast_data == NULL) lock->l_ast_data = data; if (lock->l_ast_data == data) rc = 0; LDLM_LOCK_PUT(lock); } RETURN(rc); } EXPORT_SYMBOL(ldlm_lock_set_data); struct export_cl_data { struct obd_export *ecl_exp; int ecl_loop; }; static void ldlm_cancel_lock_for_export(struct obd_export *exp, struct ldlm_lock *lock, struct export_cl_data *ecl) { struct ldlm_resource *res; res = ldlm_resource_getref(lock->l_resource); ldlm_res_lvbo_update(res, NULL, 1); ldlm_lock_cancel(lock); if (!exp->exp_obd->obd_stopping) ldlm_reprocess_all(res); ldlm_resource_putref(res); ecl->ecl_loop++; if ((ecl->ecl_loop & -ecl->ecl_loop) == ecl->ecl_loop) { CDEBUG(D_INFO, "Export %p, %d locks cancelled.\n", exp, ecl->ecl_loop); } } /** * Iterator function for ldlm_export_cancel_locks. * Cancels passed locks. */ static int ldlm_cancel_locks_for_export_cb(struct cfs_hash *hs, struct cfs_hash_bd *bd, struct hlist_node *hnode, void *data) { struct export_cl_data *ecl = (struct export_cl_data *)data; struct obd_export *exp = ecl->ecl_exp; struct ldlm_lock *lock = cfs_hash_object(hs, hnode); LDLM_LOCK_GET(lock); ldlm_cancel_lock_for_export(exp, lock, ecl); LDLM_LOCK_RELEASE(lock); return 0; } /** * Cancel all blocked locks for given export. * * Typically called on client disconnection/eviction */ int ldlm_export_cancel_blocked_locks(struct obd_export *exp) { struct export_cl_data ecl = { .ecl_exp = exp, .ecl_loop = 0, }; while (!list_empty(&exp->exp_bl_list)) { struct ldlm_lock *lock; spin_lock_bh(&exp->exp_bl_list_lock); if (!list_empty(&exp->exp_bl_list)) { lock = list_entry(exp->exp_bl_list.next, struct ldlm_lock, l_exp_list); LDLM_LOCK_GET(lock); list_del_init(&lock->l_exp_list); } else { lock = NULL; } spin_unlock_bh(&exp->exp_bl_list_lock); if (lock == NULL) break; ldlm_cancel_lock_for_export(exp, lock, &ecl); LDLM_LOCK_RELEASE(lock); } CDEBUG(D_DLMTRACE, "Export %p, canceled %d locks, " "left on hash table %d.\n", exp, ecl.ecl_loop, atomic_read(&exp->exp_lock_hash->hs_count)); return ecl.ecl_loop; } /** * Cancel all locks for given export. * * Typically called after client disconnection/eviction */ int ldlm_export_cancel_locks(struct obd_export *exp) { struct export_cl_data ecl = { .ecl_exp = exp, .ecl_loop = 0, }; cfs_hash_for_each_empty(exp->exp_lock_hash, ldlm_cancel_locks_for_export_cb, &ecl); CDEBUG(D_DLMTRACE, "Export %p, canceled %d locks, " "left on hash table %d.\n", exp, ecl.ecl_loop, atomic_read(&exp->exp_lock_hash->hs_count)); return ecl.ecl_loop; } /** * Downgrade an exclusive lock. * * A fast variant of ldlm_lock_convert for convertion of exclusive * locks. The convertion is always successful. * Used by Commit on Sharing (COS) code. * * \param lock A lock to convert * \param new_mode new lock mode */ void ldlm_lock_downgrade(struct ldlm_lock *lock, enum ldlm_mode new_mode) { ENTRY; LASSERT(lock->l_granted_mode & (LCK_PW | LCK_EX)); LASSERT(new_mode == LCK_COS); lock_res_and_lock(lock); ldlm_resource_unlink_lock(lock); /* * Remove the lock from pool as it will be added again in * ldlm_grant_lock() called below. */ ldlm_pool_del(&ldlm_lock_to_ns(lock)->ns_pool, lock); lock->l_req_mode = new_mode; ldlm_grant_lock(lock, NULL); unlock_res_and_lock(lock); ldlm_reprocess_all(lock->l_resource); EXIT; } EXPORT_SYMBOL(ldlm_lock_downgrade); /** * Attempt to convert already granted lock to a different mode. * * While lock conversion is not currently used, future client-side * optimizations could take advantage of it to avoid discarding cached * pages on a file. */ struct ldlm_resource *ldlm_lock_convert(struct ldlm_lock *lock, enum ldlm_mode new_mode, __u32 *flags) { struct list_head rpc_list; struct ldlm_resource *res; struct ldlm_namespace *ns; int granted = 0; #ifdef HAVE_SERVER_SUPPORT int old_mode; struct sl_insert_point prev; #endif struct ldlm_interval *node; ENTRY; INIT_LIST_HEAD(&rpc_list); /* Just return if mode is unchanged. */ if (new_mode == lock->l_granted_mode) { *flags |= LDLM_FL_BLOCK_GRANTED; RETURN(lock->l_resource); } /* I can't check the type of lock here because the bitlock of lock * is not held here, so do the allocation blindly. -jay */ OBD_SLAB_ALLOC_PTR_GFP(node, ldlm_interval_slab, GFP_NOFS); if (node == NULL) /* Actually, this causes EDEADLOCK to be returned */ RETURN(NULL); LASSERTF((new_mode == LCK_PW && lock->l_granted_mode == LCK_PR), "new_mode %u, granted %u\n", new_mode, lock->l_granted_mode); lock_res_and_lock(lock); res = lock->l_resource; ns = ldlm_res_to_ns(res); #ifdef HAVE_SERVER_SUPPORT old_mode = lock->l_req_mode; #endif lock->l_req_mode = new_mode; if (res->lr_type == LDLM_PLAIN || res->lr_type == LDLM_IBITS) { #ifdef HAVE_SERVER_SUPPORT /* remember the lock position where the lock might be * added back to the granted list later and also * remember the join mode for skiplist fixing. */ prev.res_link = lock->l_res_link.prev; prev.mode_link = lock->l_sl_mode.prev; prev.policy_link = lock->l_sl_policy.prev; #endif ldlm_resource_unlink_lock(lock); } else { ldlm_resource_unlink_lock(lock); if (res->lr_type == LDLM_EXTENT) { /* FIXME: ugly code, I have to attach the lock to a * interval node again since perhaps it will be granted * soon */ INIT_LIST_HEAD(&node->li_group); ldlm_interval_attach(node, lock); node = NULL; } } /* * Remove old lock from the pool before adding the lock with new * mode below in ->policy() */ ldlm_pool_del(&ns->ns_pool, lock); /* If this is a local resource, put it on the appropriate list. */ if (ns_is_client(ldlm_res_to_ns(res))) { if (*flags & (LDLM_FL_BLOCK_CONV | LDLM_FL_BLOCK_GRANTED)) { ldlm_resource_add_lock(res, &res->lr_converting, lock); } else { /* This should never happen, because of the way the * server handles conversions. */ LDLM_ERROR(lock, "Erroneous flags %x on local lock\n", *flags); LBUG(); ldlm_grant_lock(lock, &rpc_list); granted = 1; /* FIXME: completion handling not with lr_lock held ! */ if (lock->l_completion_ast) lock->l_completion_ast(lock, 0, NULL); } #ifdef HAVE_SERVER_SUPPORT } else { int rc; enum ldlm_error err; __u64 pflags = 0; ldlm_processing_policy policy; policy = ldlm_processing_policy_table[res->lr_type]; rc = policy(lock, &pflags, 0, &err, &rpc_list); if (rc == LDLM_ITER_STOP) { lock->l_req_mode = old_mode; if (res->lr_type == LDLM_EXTENT) ldlm_extent_add_lock(res, lock); else ldlm_granted_list_add_lock(lock, &prev); res = NULL; } else { *flags |= LDLM_FL_BLOCK_GRANTED; granted = 1; } } #else } else { CERROR("This is client-side-only module, cannot handle " "LDLM_NAMESPACE_SERVER resource type lock.\n"); LBUG(); } #endif unlock_res_and_lock(lock); if (granted) ldlm_run_ast_work(ns, &rpc_list, LDLM_WORK_CP_AST); if (node) OBD_SLAB_FREE(node, ldlm_interval_slab, sizeof(*node)); RETURN(res); } /** * Print lock with lock handle \a lockh description into debug log. * * Used when printing all locks on a resource for debug purposes. */ void ldlm_lock_dump_handle(int level, struct lustre_handle *lockh) { struct ldlm_lock *lock; if (!((libcfs_debug | D_ERROR) & level)) return; lock = ldlm_handle2lock(lockh); if (lock == NULL) return; LDLM_DEBUG_LIMIT(level, lock, "###"); LDLM_LOCK_PUT(lock); } EXPORT_SYMBOL(ldlm_lock_dump_handle); /** * Print lock information with custom message into debug log. * Helper function. */ void _ldlm_lock_debug(struct ldlm_lock *lock, struct libcfs_debug_msg_data *msgdata, const char *fmt, ...) { va_list args; struct obd_export *exp = lock->l_export; struct ldlm_resource *resource = lock->l_resource; char *nid = "local"; va_start(args, fmt); if (exp && exp->exp_connection) { nid = libcfs_nid2str(exp->exp_connection->c_peer.nid); } else if (exp && exp->exp_obd != NULL) { struct obd_import *imp = exp->exp_obd->u.cli.cl_import; nid = libcfs_nid2str(imp->imp_connection->c_peer.nid); } if (resource == NULL) { libcfs_debug_vmsg2(msgdata, fmt, args, " ns: \?\? lock: %p/"LPX64" lrc: %d/%d,%d mode: %s/%s " "res: \?\? rrc=\?\? type: \?\?\? flags: "LPX64" nid: %s " "remote: "LPX64" expref: %d pid: %u timeout: %lu " "lvb_type: %d\n", lock, lock->l_handle.h_cookie, atomic_read(&lock->l_refc), lock->l_readers, lock->l_writers, ldlm_lockname[lock->l_granted_mode], ldlm_lockname[lock->l_req_mode], lock->l_flags, nid, lock->l_remote_handle.cookie, exp ? atomic_read(&exp->exp_refcount) : -99, lock->l_pid, lock->l_callback_timeout, lock->l_lvb_type); va_end(args); return; } switch (resource->lr_type) { case LDLM_EXTENT: libcfs_debug_vmsg2(msgdata, fmt, args, " ns: %s lock: %p/"LPX64" lrc: %d/%d,%d mode: %s/%s " "res: "DLDLMRES" rrc: %d type: %s ["LPU64"->"LPU64"] " "(req "LPU64"->"LPU64") flags: "LPX64" nid: %s remote: " LPX64" expref: %d pid: %u timeout: %lu lvb_type: %d\n", ldlm_lock_to_ns_name(lock), lock, lock->l_handle.h_cookie, atomic_read(&lock->l_refc), lock->l_readers, lock->l_writers, ldlm_lockname[lock->l_granted_mode], ldlm_lockname[lock->l_req_mode], PLDLMRES(resource), atomic_read(&resource->lr_refcount), ldlm_typename[resource->lr_type], lock->l_policy_data.l_extent.start, lock->l_policy_data.l_extent.end, lock->l_req_extent.start, lock->l_req_extent.end, lock->l_flags, nid, lock->l_remote_handle.cookie, exp ? atomic_read(&exp->exp_refcount) : -99, lock->l_pid, lock->l_callback_timeout, lock->l_lvb_type); break; case LDLM_FLOCK: libcfs_debug_vmsg2(msgdata, fmt, args, " ns: %s lock: %p/"LPX64" lrc: %d/%d,%d mode: %s/%s " "res: "DLDLMRES" rrc: %d type: %s pid: %d " "["LPU64"->"LPU64"] flags: "LPX64" nid: %s " "remote: "LPX64" expref: %d pid: %u timeout: %lu\n", ldlm_lock_to_ns_name(lock), lock, lock->l_handle.h_cookie, atomic_read(&lock->l_refc), lock->l_readers, lock->l_writers, ldlm_lockname[lock->l_granted_mode], ldlm_lockname[lock->l_req_mode], PLDLMRES(resource), atomic_read(&resource->lr_refcount), ldlm_typename[resource->lr_type], lock->l_policy_data.l_flock.pid, lock->l_policy_data.l_flock.start, lock->l_policy_data.l_flock.end, lock->l_flags, nid, lock->l_remote_handle.cookie, exp ? atomic_read(&exp->exp_refcount) : -99, lock->l_pid, lock->l_callback_timeout); break; case LDLM_IBITS: libcfs_debug_vmsg2(msgdata, fmt, args, " ns: %s lock: %p/"LPX64" lrc: %d/%d,%d mode: %s/%s " "res: "DLDLMRES" bits "LPX64" rrc: %d type: %s " "flags: "LPX64" nid: %s remote: "LPX64" expref: %d " "pid: %u timeout: %lu lvb_type: %d\n", ldlm_lock_to_ns_name(lock), lock, lock->l_handle.h_cookie, atomic_read(&lock->l_refc), lock->l_readers, lock->l_writers, ldlm_lockname[lock->l_granted_mode], ldlm_lockname[lock->l_req_mode], PLDLMRES(resource), lock->l_policy_data.l_inodebits.bits, atomic_read(&resource->lr_refcount), ldlm_typename[resource->lr_type], lock->l_flags, nid, lock->l_remote_handle.cookie, exp ? atomic_read(&exp->exp_refcount) : -99, lock->l_pid, lock->l_callback_timeout, lock->l_lvb_type); break; default: libcfs_debug_vmsg2(msgdata, fmt, args, " ns: %s lock: %p/"LPX64" lrc: %d/%d,%d mode: %s/%s " "res: "DLDLMRES" rrc: %d type: %s flags: "LPX64" " "nid: %s remote: "LPX64" expref: %d pid: %u " "timeout: %lu lvb_type: %d\n", ldlm_lock_to_ns_name(lock), lock, lock->l_handle.h_cookie, atomic_read(&lock->l_refc), lock->l_readers, lock->l_writers, ldlm_lockname[lock->l_granted_mode], ldlm_lockname[lock->l_req_mode], PLDLMRES(resource), atomic_read(&resource->lr_refcount), ldlm_typename[resource->lr_type], lock->l_flags, nid, lock->l_remote_handle.cookie, exp ? atomic_read(&exp->exp_refcount) : -99, lock->l_pid, lock->l_callback_timeout, lock->l_lvb_type); break; } va_end(args); } EXPORT_SYMBOL(_ldlm_lock_debug);