1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
2 * vim:expandtab:shiftwidth=8:tabstop=8:
4 * Copyright (C) 2005 Cluster File Systems, Inc.
5 * Author: YuZhangyong <yzy@clusterfs.com>
7 * This file is part of Lustre, http://www.lustre.org/
9 * No redistribution or use is permitted outside of Cluster File Systems, Inc.
11 * Implement a hash class for hash process in lustre system.
15 #include <liblustre.h>
19 #include <obd_class.h>
20 #include <class_hash.h>
21 #include <lustre_export.h>
22 #include <obd_support.h>
23 #include <lustre_net.h>
25 int lustre_hash_init(struct lustre_class_hash_body **hash_body_new,
26 char *hashname, __u32 hashsize,
27 struct lustre_hash_operations *hash_operations)
30 struct lustre_class_hash_body *hash_body = NULL;
32 LASSERT(hashsize > 0);
33 LASSERT(hash_operations != NULL);
43 LASSERTF(n == 1, "hashsize %u isn't 2^n\n", hashsize);
45 /* alloc space for hash_body */
46 OBD_ALLOC(hash_body, sizeof(*hash_body));
48 if (hash_body == NULL) {
49 CERROR("Cannot alloc space for hash body, hashname = %s \n",
54 LASSERT(hashname != NULL &&
55 strlen(hashname) <= sizeof(hash_body->hashname));
56 strcpy(hash_body->hashname, hashname);
57 hash_body->lchb_hash_max_size = hashsize;
58 hash_body->lchb_hash_operations = hash_operations;
60 /* alloc space for the hash tables */
61 OBD_ALLOC(hash_body->lchb_hash_tables,
62 sizeof(*hash_body->lchb_hash_tables) * hash_body->lchb_hash_max_size);
64 if (hash_body->lchb_hash_tables == NULL) {
65 OBD_FREE(hash_body, sizeof(*hash_body));
66 CERROR("Cannot alloc space for hashtables, hashname = %s \n",
71 spin_lock_init(&hash_body->lchb_lock); /* initialize the body lock */
73 for(i =0 ; i < hash_body->lchb_hash_max_size; i++) {
74 /* initial the bucket lock and list_head */
75 INIT_HLIST_HEAD(&hash_body->lchb_hash_tables[i].lhb_head);
76 spin_lock_init(&hash_body->lchb_hash_tables[i].lhb_lock);
78 *hash_body_new = hash_body;
82 EXPORT_SYMBOL(lustre_hash_init);
84 void lustre_hash_exit(struct lustre_class_hash_body **new_hash_body)
87 struct lustre_class_hash_body *hash_body = NULL;
90 hash_body = *new_hash_body;
92 if (hash_body == NULL) {
93 CWARN("hash body has been deleted\n");
97 spin_lock(&hash_body->lchb_lock); /* lock the hash tables */
99 if (hash_body->lchb_hash_tables == NULL ) {
100 spin_unlock(&hash_body->lchb_lock);
101 CWARN("hash tables has been deleted\n");
105 for( i = 0; i < hash_body->lchb_hash_max_size; i++ ) {
106 struct lustre_hash_bucket * bucket;
107 struct hlist_node * actual_hnode, *pos;
109 bucket = &hash_body->lchb_hash_tables[i];
110 spin_lock(&bucket->lhb_lock); /* lock the bucket */
111 hlist_for_each_safe(actual_hnode, pos, &(bucket->lhb_head)) {
112 lustre_hash_delitem_nolock(hash_body, i, actual_hnode);
114 spin_unlock(&bucket->lhb_lock);
117 /* free the hash_tables's memory space */
118 OBD_FREE(hash_body->lchb_hash_tables,
119 sizeof(*hash_body->lchb_hash_tables) * hash_body->lchb_hash_max_size);
121 hash_body->lchb_hash_tables = NULL;
123 spin_unlock(&hash_body->lchb_lock);
126 /* free the hash_body's memory space */
127 if (hash_body != NULL) {
128 OBD_FREE(hash_body, sizeof(*hash_body));
129 *new_hash_body = NULL;
133 EXPORT_SYMBOL(lustre_hash_exit);
136 * only allow unique @key in hashtables, if the same @key has existed
137 * in hashtables, it will return with fails.
139 int lustre_hash_additem_unique(struct lustre_class_hash_body *hash_body,
140 void *key, struct hlist_node *actual_hnode)
143 struct lustre_hash_bucket *bucket = NULL;
144 struct lustre_hash_operations *hop = hash_body->lchb_hash_operations;
147 hashent = hop->lustre_hashfn(hash_body, key);
149 /* get the hash-bucket and lock it */
150 bucket = &hash_body->lchb_hash_tables[hashent];
151 spin_lock(&bucket->lhb_lock);
153 if ( (lustre_hash_getitem_in_bucket_nolock(hash_body, hashent, key)) != NULL) {
154 /* the added-item exist in hashtables, so cannot add it again */
155 spin_unlock(&bucket->lhb_lock);
157 CWARN("Already found the key in hash [%s]\n",
158 hash_body->hashname);
162 hlist_add_head(actual_hnode, &(bucket->lhb_head));
164 #ifdef LUSTRE_HASH_DEBUG
165 /* hash distribute debug */
166 hash_body->lchb_hash_tables[hashent].lhb_item_count++;
167 CDEBUG(D_INFO, "hashname[%s] bucket[%d] has [%d] hashitem\n",
168 hash_body->hashname, hashent,
169 hash_body->lchb_hash_tables[hashent].lhb_item_count);
171 hop->lustre_hash_object_refcount_get(actual_hnode);
173 spin_unlock(&bucket->lhb_lock);
177 EXPORT_SYMBOL(lustre_hash_additem_unique);
180 * this version of additem, it allow multi same @key <key, value> in hashtables.
181 * in this additem version, we don't need to check if exist same @key in hash
182 * tables, we only add it to related hashbucket.
183 * example: maybe same nid will be related to multi difference export
185 int lustre_hash_additem(struct lustre_class_hash_body *hash_body, void *key,
186 struct hlist_node *actual_hnode)
189 struct lustre_hash_bucket *bucket = NULL;
190 struct lustre_hash_operations *hop = hash_body->lchb_hash_operations;
193 hashent = hop->lustre_hashfn(hash_body, key);
195 /* get the hashbucket and lock it */
196 bucket = &hash_body->lchb_hash_tables[hashent];
197 spin_lock(&bucket->lhb_lock);
199 hlist_add_head(actual_hnode, &(bucket->lhb_head));
201 #ifdef LUSTRE_HASH_DEBUG
202 /* hash distribute debug */
203 hash_body->lchb_hash_tables[hashent].lhb_item_count++;
204 CDEBUG(D_INFO, "hashname[%s] bucket[%d] has [%d] hashitem\n",
205 hash_body->hashname, hashent,
206 hash_body->lchb_hash_tables[hashent].lhb_item_count);
208 hop->lustre_hash_object_refcount_get(actual_hnode);
210 spin_unlock(&bucket->lhb_lock);
214 EXPORT_SYMBOL(lustre_hash_additem);
218 * this version of delitem will delete a hashitem with given @key,
219 * we need to search the <@key, @value> in hashbucket with @key,
220 * if match, the hashitem will be delete.
221 * we have a no-search version of delitem, it will directly delete a hashitem,
222 * doesn't need to search it in hashtables, so it is a O(1) delete.
224 int lustre_hash_delitem_by_key(struct lustre_class_hash_body *hash_body,
228 struct hlist_node * hash_item;
229 struct lustre_hash_bucket *bucket = NULL;
230 struct lustre_hash_operations *hop = hash_body->lchb_hash_operations;
234 hashent = hop->lustre_hashfn(hash_body, key);
236 /* first, lock the hashbucket */
237 bucket = &hash_body->lchb_hash_tables[hashent];
238 spin_lock(&bucket->lhb_lock);
240 /* get the hash_item from hash_bucket */
241 hash_item = lustre_hash_getitem_in_bucket_nolock(hash_body, hashent,
244 if (hash_item == NULL) {
248 /* call delitem_nolock() to delete the hash_item */
249 retval = lustre_hash_delitem_nolock(hash_body, hashent, hash_item);
251 spin_unlock(&bucket->lhb_lock);
255 EXPORT_SYMBOL(lustre_hash_delitem_by_key);
258 * the O(1) version of delete hash item,
259 * it will directly delete the hashitem with given @hash_item,
260 * the parameter @key used to get the relation hash bucket and lock it.
262 int lustre_hash_delitem(struct lustre_class_hash_body *hash_body,
263 void *key, struct hlist_node * hash_item)
267 struct lustre_hash_bucket *bucket = NULL;
268 struct lustre_hash_operations *hop = hash_body->lchb_hash_operations;
271 hashent = hop->lustre_hashfn(hash_body, key);
273 bucket = &hash_body->lchb_hash_tables[hashent];
274 spin_lock(&bucket->lhb_lock);
276 /* call delitem_nolock() to delete the hash_item */
277 retval = lustre_hash_delitem_nolock(hash_body, hashent, hash_item);
279 spin_unlock(&bucket->lhb_lock);
283 EXPORT_SYMBOL(lustre_hash_delitem);
285 void * lustre_hash_get_object_by_key(struct lustre_class_hash_body *hash_body,
289 struct hlist_node * hash_item_hnode = NULL;
290 void * obj_value = NULL;
291 struct lustre_hash_bucket *bucket = NULL;
292 struct lustre_hash_operations * hop = hash_body->lchb_hash_operations;
295 /* get the hash value from the given item */
296 hashent = hop->lustre_hashfn(hash_body, key);
298 bucket = &hash_body->lchb_hash_tables[hashent];
299 spin_lock(&bucket->lhb_lock); /* lock the bucket */
301 hash_item_hnode = lustre_hash_getitem_in_bucket_nolock(hash_body,
304 if (hash_item_hnode == NULL) {
305 spin_unlock(&bucket->lhb_lock); /* lock the bucket */
309 obj_value = hop->lustre_hash_object_refcount_get(hash_item_hnode);
310 spin_unlock(&bucket->lhb_lock); /* lock the bucket */
314 EXPORT_SYMBOL(lustre_hash_get_object_by_key);
317 * define (uuid <-> export) hash operations and function define
320 /* define the uuid hash operations */
321 struct lustre_hash_operations uuid_hash_operations = {
322 .lustre_hashfn = uuid_hashfn,
323 .lustre_hash_key_compare = uuid_hash_key_compare,
324 .lustre_hash_object_refcount_get = uuid_export_refcount_get,
325 .lustre_hash_object_refcount_put = uuid_export_refcount_put,
328 /* string hashing using djb2 hash algorithm */
329 __u32 uuid_hashfn(struct lustre_class_hash_body *hash_body, void * key)
332 struct obd_uuid * uuid_key = NULL;
336 LASSERT(key != NULL);
338 uuid_key = (struct obd_uuid*)key;
339 ptr = uuid_key->uuid;
341 while ((c = *ptr++)) {
342 hash = hash * 33 + c;
345 hash &= (hash_body->lchb_hash_max_size - 1);
350 int uuid_hash_key_compare(void *key, struct hlist_node *compared_hnode)
352 struct obd_export *export = NULL;
353 struct obd_uuid *uuid_key = NULL, *compared_uuid = NULL;
355 LASSERT( key != NULL);
357 uuid_key = (struct obd_uuid*)key;
359 export = hlist_entry(compared_hnode, struct obd_export, exp_uuid_hash);
361 compared_uuid = &export->exp_client_uuid;
363 RETURN(obd_uuid_equals(uuid_key, compared_uuid));
366 void * uuid_export_refcount_get(struct hlist_node * actual_hnode)
368 struct obd_export *export = NULL;
370 LASSERT(actual_hnode != NULL);
372 export = hlist_entry(actual_hnode, struct obd_export, exp_uuid_hash);
374 LASSERT(export != NULL);
376 class_export_get(export);
381 void uuid_export_refcount_put(struct hlist_node * actual_hnode)
383 struct obd_export *export = NULL;
385 LASSERT(actual_hnode != NULL);
387 export = hlist_entry(actual_hnode, struct obd_export, exp_uuid_hash);
389 LASSERT(export != NULL);
391 class_export_put(export);
395 * define (nid <-> export) hash operations and function define
398 /* define the nid hash operations */
399 struct lustre_hash_operations nid_hash_operations = {
400 .lustre_hashfn = nid_hashfn,
401 .lustre_hash_key_compare = nid_hash_key_compare,
402 .lustre_hash_object_refcount_get = nid_export_refcount_get,
403 .lustre_hash_object_refcount_put = nid_export_refcount_put,
406 /* string hashing using djb2 hash algorithm */
407 __u32 nid_hashfn(struct lustre_class_hash_body *hash_body, void * key)
410 lnet_nid_t *nid_key = NULL;
414 LASSERT(key != NULL);
416 nid_key = (lnet_nid_t*)key;
417 ptr = libcfs_nid2str(*nid_key);
419 while ((c = *ptr++)) {
420 hash = hash * 33 + c;
423 hash &= (hash_body->lchb_hash_max_size - 1);
428 int nid_hash_key_compare(void *key, struct hlist_node *compared_hnode)
430 struct obd_export *export = NULL;
431 lnet_nid_t *nid_key = NULL;
434 LASSERT( key != NULL);
436 nid_key = (lnet_nid_t*)key;
438 export = hlist_entry(compared_hnode, struct obd_export, exp_nid_hash);
440 if (strcmp(obd_export_nid2str(export), libcfs_nid2str(*nid_key)) == 0)
446 void * nid_export_refcount_get(struct hlist_node * actual_hnode)
448 struct obd_export *export = NULL;
450 LASSERT(actual_hnode != NULL);
452 export = hlist_entry(actual_hnode, struct obd_export, exp_nid_hash);
454 LASSERT(export != NULL);
456 class_export_get(export);
461 void nid_export_refcount_put(struct hlist_node * actual_hnode)
463 struct obd_export *export = NULL;
465 LASSERT(actual_hnode != NULL);
467 export = hlist_entry(actual_hnode, struct obd_export, exp_nid_hash);
469 LASSERT(export != NULL);
471 class_export_put(export);
475 * define (net_peer <-> connection) hash operations and function define
478 /* define the conn hash operations */
479 struct lustre_hash_operations conn_hash_operations = {
480 .lustre_hashfn = conn_hashfn,
481 .lustre_hash_key_compare = conn_hash_key_compare,
482 .lustre_hash_object_refcount_get = conn_refcount_get,
483 .lustre_hash_object_refcount_put = conn_refcount_put,
485 EXPORT_SYMBOL(conn_hash_operations);
487 /* string hashing using djb2 hash algorithm */
488 __u32 conn_hashfn(struct lustre_class_hash_body *hash_body, void * key)
491 lnet_process_id_t *conn_key = NULL;
495 LASSERT(key != NULL);
497 conn_key = (lnet_process_id_t*)key;
498 ptr = libcfs_id2str(*conn_key);
500 while ((c = *ptr++)) {
501 hash = hash * 33 + c;
504 hash &= (hash_body->lchb_hash_max_size - 1);
509 int conn_hash_key_compare(void *key, struct hlist_node *compared_hnode)
511 struct ptlrpc_connection *c = NULL;
512 lnet_process_id_t *conn_key = NULL;
515 LASSERT( key != NULL);
517 conn_key = (lnet_process_id_t*)key;
519 c = hlist_entry(compared_hnode, struct ptlrpc_connection, c_hash);
521 if (conn_key->nid == c->c_peer.nid &&
522 conn_key->pid == c->c_peer.pid)
528 void * conn_refcount_get(struct hlist_node * actual_hnode)
530 struct ptlrpc_connection *c = NULL;
532 LASSERT(actual_hnode != NULL);
534 c = hlist_entry(actual_hnode, struct ptlrpc_connection, c_hash);
538 atomic_inc(&c->c_refcount);
543 void conn_refcount_put(struct hlist_node * actual_hnode)
545 struct ptlrpc_connection *c = NULL;
547 LASSERT(actual_hnode != NULL);
549 c = hlist_entry(actual_hnode, struct ptlrpc_connection, c_hash);
553 atomic_dec(&c->c_refcount);