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* 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, 2012, 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 <braam@clusterfs.com>
* Author: Phil Schwan <phil@clusterfs.com>
*/
#define DEBUG_SUBSYSTEM S_LDLM
#include "../../include/linux/libcfs/libcfs.h"
#include "../include/lustre_intent.h"
#include "../include/obd_class.h"
#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",
};
EXPORT_SYMBOL(ldlm_typename);
static ldlm_policy_wire_to_local_t ldlm_policy_wire18_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_wire18_to_local,
[LDLM_IBITS - LDLM_MIN_TYPE] = ldlm_ibits_policy_wire_to_local,
};
static ldlm_policy_wire_to_local_t ldlm_policy_wire21_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_wire21_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(ldlm_type_t type,
const ldlm_policy_data_t *lpolicy,
ldlm_wire_policy_data_t *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, ldlm_type_t type,
const ldlm_wire_policy_data_t *wpolicy,
ldlm_policy_data_t *lpolicy)
{
ldlm_policy_wire_to_local_t convert;
int new_client;
/** some badness for 2.0.0 clients, but 2.0.0 isn't supported */
new_client = (exp_connect_flags(exp) & OBD_CONNECT_FULL20) != 0;
if (new_client)
convert = ldlm_policy_wire21_to_local[type - LDLM_MIN_TYPE];
else
convert = ldlm_policy_wire18_to_local[type - LDLM_MIN_TYPE];
convert(wpolicy, lpolicy);
}
char *ldlm_it2str(int 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 %d\n", it);
return "UNKNOWN";
}
}
EXPORT_SYMBOL(ldlm_it2str);
extern struct kmem_cache *ldlm_lock_slab;
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)
{
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(lock->l_flags & LDLM_FL_DESTROYED);
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(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);
}
}
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.
*/
int ldlm_lock_remove_from_lru(struct ldlm_lock *lock)
{
struct ldlm_namespace *ns = ldlm_lock_to_ns(lock);
int rc;
if (lock->l_flags & LDLM_FL_NS_SRV) {
LASSERT(list_empty(&lock->l_lru));
return 0;
}
spin_lock(&ns->ns_lock);
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);
if (lock->l_flags & LDLM_FL_SKIPPED)
lock->l_flags &= ~LDLM_FL_SKIPPED;
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);
spin_lock(&ns->ns_lock);
ldlm_lock_add_to_lru_nolock(lock);
spin_unlock(&ns->ns_lock);
}
/**
* 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);
if (lock->l_flags & LDLM_FL_NS_SRV) {
LASSERT(list_empty(&lock->l_lru));
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);
}
/**
* 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
*/
int ldlm_lock_destroy_internal(struct ldlm_lock *lock)
{
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 (lock->l_flags & LDLM_FL_DESTROYED) {
LASSERT(list_empty(&lock->l_lru));
return 0;
}
lock->l_flags |= LDLM_FL_DESTROYED;
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
return 1;
}
/**
* Destroys a LDLM lock \a lock. Performs necessary locking first.
*/
void ldlm_lock_destroy(struct ldlm_lock *lock)
{
int first;
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);
}
}
/**
* Destroys a LDLM lock \a lock that is already locked.
*/
void ldlm_lock_destroy_nolock(struct ldlm_lock *lock)
{
int first;
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);
}
}
/* 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);
}
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;
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;
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 (newres == NULL)
return -ENOMEM;
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;
}
EXPORT_SYMBOL(ldlm_lock_change_resource);
/** \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;
LASSERT(handle);
lock = class_handle2object(handle->cookie);
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 && ((lock->l_flags & LDLM_FL_DESTROYED)== 0)) {
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(lock->l_flags & LDLM_FL_DESTROYED)) {
unlock_res_and_lock(lock);
CDEBUG(D_INFO, "lock already destroyed: lock %p\n", lock);
LDLM_LOCK_PUT(lock);
return NULL;
}
if (flags && (lock->l_flags & flags)) {
unlock_res_and_lock(lock);
LDLM_LOCK_PUT(lock);
return NULL;
}
if (flags)
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);
}
EXPORT_SYMBOL(ldlm_lock2desc);
/**
* 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.
*/
void ldlm_add_bl_work_item(struct ldlm_lock *lock, struct ldlm_lock *new,
struct list_head *work_list)
{
if ((lock->l_flags & LDLM_FL_AST_SENT) == 0) {
LDLM_DEBUG(lock, "lock incompatible; sending blocking AST.");
lock->l_flags |= LDLM_FL_AST_SENT;
/* If the enqueuing client said so, tell the AST recipient to
* discard dirty data, rather than writing back. */
if (new->l_flags & LDLM_FL_AST_DISCARD_DATA)
lock->l_flags |= LDLM_FL_DISCARD_DATA;
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.
*/
void ldlm_add_cp_work_item(struct ldlm_lock *lock, struct list_head *work_list)
{
if ((lock->l_flags & LDLM_FL_CP_REQD) == 0) {
lock->l_flags |= LDLM_FL_CP_REQD;
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)
{
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);
}
/**
* 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, __u32 mode)
{
struct ldlm_lock *lock;
lock = ldlm_handle2lock(lockh);
LASSERT(lock != NULL);
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, __u32 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, __u32 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 ||
!(lock->l_flags & LDLM_FL_CBPENDING)) {
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, __u32 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 accommodate flock locks
* that cannot be placed in LRU.
*/
void ldlm_lock_decref_internal_nolock(struct ldlm_lock *lock, __u32 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, __u32 mode)
{
struct ldlm_namespace *ns;
lock_res_and_lock(lock);
ns = ldlm_lock_to_ns(lock);
ldlm_lock_decref_internal_nolock(lock, mode);
if (lock->l_flags & LDLM_FL_LOCAL &&
!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. */
CDEBUG(D_INFO, "forcing cancel of local lock\n");
lock->l_flags |= LDLM_FL_CBPENDING;
}
if (!lock->l_readers && !lock->l_writers &&
(lock->l_flags & LDLM_FL_CBPENDING)) {
/* If we received a blocked AST and this was the last reference,
* run the callback. */
if ((lock->l_flags & LDLM_FL_NS_SRV) && 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 (lock->l_flags & LDLM_FL_FAIL_LOC)
OBD_RACE(OBD_FAIL_LDLM_CP_BL_RACE);
if ((lock->l_flags & LDLM_FL_ATOMIC_CB) ||
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 &&
!(lock->l_flags & LDLM_FL_NO_LRU) &&
!(lock->l_flags & LDLM_FL_BL_AST)) {
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 (lock->l_flags & LDLM_FL_FAIL_LOC)
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);
}
}
/**
* Decrease reader/writer refcount for LDLM lock with handle \a lockh
*/
void ldlm_lock_decref(struct lustre_handle *lockh, __u32 mode)
{
struct ldlm_lock *lock = __ldlm_handle2lock(lockh, 0);
LASSERTF(lock != NULL, "Non-existing lock: %#llx\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.
*
* Typical usage is for GROUP locks which we cannot allow to be cached.
*/
void ldlm_lock_decref_and_cancel(struct lustre_handle *lockh, __u32 mode)
{
struct ldlm_lock *lock = __ldlm_handle2lock(lockh, 0);
LASSERT(lock != NULL);
LDLM_DEBUG(lock, "ldlm_lock_decref(%s)", ldlm_lockname[mode]);
lock_res_and_lock(lock);
lock->l_flags |= LDLM_FL_CBPENDING;
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;
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;
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;
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;
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;
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;
check_res_locked(res);
ldlm_resource_dump(D_INFO, res);
LDLM_DEBUG(lock, "About to add lock:");
if (lock->l_flags & LDLM_FL_DESTROYED) {
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);
}
/**
* 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;
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);
}
/**
* 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;
check_res_locked(res);
lock->l_granted_mode = lock->l_req_mode;
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);
if (lock->l_granted_mode < res->lr_most_restr)
res->lr_most_restr = lock->l_granted_mode;
if (work_list && lock->l_completion_ast != NULL)
ldlm_add_ast_work_item(lock, NULL, work_list);
ldlm_pool_add(&ldlm_res_to_ns(res)->ns_pool, lock);
}
/**
* Search for a lock with given properties in a queue.
*
* \retval a referenced lock or NULL. See the flag descriptions below, in the
* comment above ldlm_lock_match
*/
static struct ldlm_lock *search_queue(struct list_head *queue,
ldlm_mode_t *mode,
ldlm_policy_data_t *policy,
struct ldlm_lock *old_lock,
__u64 flags, int unref)
{
struct ldlm_lock *lock;
struct list_head *tmp;
list_for_each(tmp, queue) {
ldlm_mode_t match;
lock = list_entry(tmp, struct ldlm_lock, l_res_link);
if (lock == old_lock)
break;
/* Check if this lock can be matched.
* Used by LU-2919(exclusive open) for open lease lock */
if (ldlm_is_excl(lock))
continue;
/* 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 (lock->l_flags & LDLM_FL_CBPENDING &&
!(flags & LDLM_FL_CBPENDING))
continue;
if (!unref && lock->l_flags & LDLM_FL_CBPENDING &&
lock->l_readers == 0 && lock->l_writers == 0)
continue;
if (!(lock->l_req_mode & *mode))
continue;
match = lock->l_req_mode;
if (lock->l_resource->lr_type == LDLM_EXTENT &&
(lock->l_policy_data.l_extent.start >
policy->l_extent.start ||
lock->l_policy_data.l_extent.end < policy->l_extent.end))
continue;
if (unlikely(match == LCK_GROUP) &&
lock->l_resource->lr_type == LDLM_EXTENT &&
lock->l_policy_data.l_extent.gid != policy->l_extent.gid)
continue;
/* We match if we have existing lock with same or wider set
of bits. */
if (lock->l_resource->lr_type == LDLM_IBITS &&
((lock->l_policy_data.l_inodebits.bits &
policy->l_inodebits.bits) !=
policy->l_inodebits.bits))
continue;
if (!unref && (lock->l_flags & LDLM_FL_GONE_MASK))
continue;
if ((flags & LDLM_FL_LOCAL_ONLY) &&
!(lock->l_flags & LDLM_FL_LOCAL))
continue;
if (flags & LDLM_FL_TEST_LOCK) {
LDLM_LOCK_GET(lock);
ldlm_lock_touch_in_lru(lock);
} else {
ldlm_lock_addref_internal_nolock(lock, match);
}
*mode = match;
return 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);
}
EXPORT_SYMBOL(ldlm_lock_fail_match);
/**
* 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)
{
lock->l_flags |= LDLM_FL_LVB_READY;
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 referneces
* 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.
*/
ldlm_mode_t ldlm_lock_match(struct ldlm_namespace *ns, __u64 flags,
const struct ldlm_res_id *res_id, ldlm_type_t type,
ldlm_policy_data_t *policy, ldlm_mode_t mode,
struct lustre_handle *lockh, int unref)
{
struct ldlm_resource *res;
struct ldlm_lock *lock, *old_lock = NULL;
int rc = 0;
if (ns == NULL) {
old_lock = ldlm_handle2lock(lockh);
LASSERT(old_lock);
ns = ldlm_lock_to_ns(old_lock);
res_id = &old_lock->l_resource->lr_name;
type = old_lock->l_resource->lr_type;
mode = old_lock->l_req_mode;
}
res = ldlm_resource_get(ns, NULL, res_id, type, 0);
if (res == NULL) {
LASSERT(old_lock == NULL);
return 0;
}
LDLM_RESOURCE_ADDREF(res);
lock_res(res);
lock = search_queue(&res->lr_granted, &mode, policy, old_lock,
flags, unref);
if (lock != NULL) {
rc = 1;
goto out;
}
if (flags & LDLM_FL_BLOCK_GRANTED) {
rc = 0;
goto out;
}
lock = search_queue(&res->lr_converting, &mode, policy, old_lock,
flags, unref);
if (lock != NULL) {
rc = 1;
goto out;
}
lock = search_queue(&res->lr_waiting, &mode, policy, old_lock,
flags, unref);
if (lock != NULL) {
rc = 1;
goto out;
}
out:
unlock_res(res);
LDLM_RESOURCE_DELREF(res);
ldlm_resource_putref(res);
if (lock) {
ldlm_lock2handle(lock, lockh);
if ((flags & LDLM_FL_LVB_READY) &&
(!(lock->l_flags & LDLM_FL_LVB_READY))) {
__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 (!(lock->l_flags & LDLM_FL_LVB_READY)) {
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 (%llu %llu)",
(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 %llu/%llu (%llu %llu)",
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 (old_lock)
LDLM_LOCK_PUT(old_lock);
return rc ? mode : 0;
}
EXPORT_SYMBOL(ldlm_lock_match);
ldlm_mode_t ldlm_revalidate_lock_handle(struct lustre_handle *lockh,
__u64 *bits)
{
struct ldlm_lock *lock;
ldlm_mode_t mode = 0;
lock = ldlm_handle2lock(lockh);
if (lock != NULL) {
lock_res_and_lock(lock);
if (lock->l_flags & LDLM_FL_GONE_MASK)
goto out;
if (lock->l_flags & LDLM_FL_CBPENDING &&
lock->l_readers == 0 && lock->l_writers == 0)
goto out;
if (bits)
*bits = lock->l_policy_data.l_inodebits.bits;
mode = lock->l_granted_mode;
ldlm_lock_addref_internal_nolock(lock, mode);
}
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;
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);
dump_stack();
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,
ldlm_type_t type,
ldlm_mode_t 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;
res = ldlm_resource_get(ns, NULL, res_id, type, 1);
if (res == NULL)
return NULL;
lock = ldlm_lock_new(res);
if (lock == NULL)
return NULL;
lock->l_req_mode = mode;
lock->l_ast_data = data;
lock->l_pid = current_pid();
if (ns_is_server(ns))
lock->l_flags |= LDLM_FL_NS_SRV;
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;
}
if (lvb_len) {
lock->l_lvb_len = lvb_len;
OBD_ALLOC(lock->l_lvb_data, lvb_len);
if (lock->l_lvb_data == NULL)
goto out;
}
lock->l_lvb_type = lvb_type;
if (OBD_FAIL_CHECK(OBD_FAIL_LDLM_NEW_LOCK))
goto out;
return lock;
out:
ldlm_lock_destroy(lock);
LDLM_LOCK_RELEASE(lock);
return NULL;
}
/**
* 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.
*/
ldlm_error_t 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));
ldlm_error_t rc = ELDLM_OK;
struct ldlm_interval *node = NULL;
lock->l_last_activity = get_seconds();
/* 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;
}
}
/* 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_BLOCK_GRANTED |
LDLM_FL_BLOCK_CONV | LDLM_FL_BLOCK_WAIT);
goto out;
}
ldlm_resource_unlink_lock(lock);
if (res->lr_type == LDLM_EXTENT && lock->l_tree_node == NULL) {
if (node == NULL) {
ldlm_lock_destroy_nolock(lock);
rc = -ENOMEM;
goto out;
}
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. */
lock->l_flags |= *flags & LDLM_FL_AST_DISCARD_DATA;
/* 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;
} else {
CERROR("This is client-side-only module, cannot handle "
"LDLM_NAMESPACE_SERVER resource type lock.\n");
LBUG();
}
out:
unlock_res_and_lock(lock);
if (node)
OBD_SLAB_FREE(node, ldlm_interval_slab, sizeof(*node));
return rc;
}
/**
* 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;
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(lock->l_flags & LDLM_FL_AST_SENT);
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;
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(lock->l_flags & LDLM_FL_CP_REQD);
/* save l_completion_ast since it can be changed by
* mds_intent_policy(), see bug 14225 */
completion_callback = lock->l_completion_ast;
lock->l_flags &= ~LDLM_FL_CP_REQD;
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;
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;
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) {
rc = -ENOMEM;
goto out;
}
ptlrpc_set_wait(arg->set);
ptlrpc_set_destroy(arg->set);
rc = atomic_read(&arg->restart) ? -ERESTART : 0;
goto out;
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)
{
if (ns != NULL) {
cfs_hash_for_each_nolock(ns->ns_rs_hash,
ldlm_reprocess_res, NULL);
}
}
EXPORT_SYMBOL(ldlm_reprocess_all_ns);
/**
* 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)
{
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();
}
}
/**
* 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 (!(lock->l_flags & LDLM_FL_CANCEL)) {
lock->l_flags |= LDLM_FL_CANCEL;
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");
}
}
lock->l_flags |= LDLM_FL_BL_DONE;
}
/**
* 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;
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 (lock->l_flags & LDLM_FL_WAITED)
ldlm_del_waiting_lock(lock);
/* Releases cancel callback. */
ldlm_cancel_callback(lock);
/* Yes, second time, just in case it was added again while we were
* running with no res lock in ldlm_cancel_callback */
if (lock->l_flags & LDLM_FL_WAITED)
ldlm_del_waiting_lock(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);
}
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;
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;
};
/**
* Iterator function for ldlm_cancel_locks_for_export.
* Cancels passed locks.
*/
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);
struct ldlm_resource *res;
res = ldlm_resource_getref(lock->l_resource);
LDLM_LOCK_GET(lock);
LDLM_DEBUG(lock, "export %p", exp);
ldlm_res_lvbo_update(res, NULL, 1);
ldlm_lock_cancel(lock);
ldlm_reprocess_all(res);
ldlm_resource_putref(res);
LDLM_LOCK_RELEASE(lock);
ecl->ecl_loop++;
if ((ecl->ecl_loop & -ecl->ecl_loop) == ecl->ecl_loop) {
CDEBUG(D_INFO,
"Cancel lock %p for export %p (loop %d), still have "
"%d locks left on hash table.\n",
lock, exp, ecl->ecl_loop,
atomic_read(&hs->hs_count));
}
return 0;
}
/**
* Cancel all locks for given export.
*
* Typically called on client disconnection/eviction
*/
void ldlm_cancel_locks_for_export(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);
}
/**
* Downgrade an exclusive lock.
*
* A fast variant of ldlm_lock_convert for conversion of exclusive
* locks. The conversion 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, int new_mode)
{
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);
}
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, int new_mode,
__u32 *flags)
{
LIST_HEAD(rpc_list);
struct ldlm_resource *res;
struct ldlm_namespace *ns;
int granted = 0;
struct ldlm_interval *node;
/* 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);
lock->l_req_mode = new_mode;
if (res->lr_type == LDLM_PLAIN || res->lr_type == LDLM_IBITS) {
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);
}
} else {
CERROR("This is client-side-only module, cannot handle "
"LDLM_NAMESPACE_SERVER resource type lock.\n");
LBUG();
}
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;
}
EXPORT_SYMBOL(ldlm_lock_convert);
/**
* 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/%#llx lrc: %d/%d,%d mode: %s/%s "
"res: \?\? rrc=\?\? type: \?\?\? flags: %#llx nid: %s "
"remote: %#llx 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/%#llx lrc: %d/%d,%d mode: %s/%s "
"res: "DLDLMRES" rrc: %d type: %s [%llu->%llu] "
"(req %llu->%llu) flags: %#llx nid: %s remote: "
"%#llx 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/%#llx lrc: %d/%d,%d mode: %s/%s "
"res: "DLDLMRES" rrc: %d type: %s pid: %d "
"[%llu->%llu] flags: %#llx nid: %s "
"remote: %#llx 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/%#llx lrc: %d/%d,%d mode: %s/%s "
"res: "DLDLMRES" bits %#llx rrc: %d type: %s "
"flags: %#llx nid: %s remote: %#llx 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/%#llx lrc: %d/%d,%d mode: %s/%s "
"res: "DLDLMRES" rrc: %d type: %s flags: %#llx "
"nid: %s remote: %#llx 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);
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