4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 only,
8 * as published by the Free Software Foundation.
10 * This program is distributed in the hope that it will be useful, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * General Public License version 2 for more details (a copy is included
14 * in the LICENSE file that accompanied this code).
16 * You should have received a copy of the GNU General Public License
17 * version 2 along with this program; If not, see
18 * http://www.gnu.org/licenses/gpl-2.0.html
23 * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
24 * Use is subject to license terms.
26 * Copyright (c) 2012, 2014, Intel Corporation.
29 * This file is part of Lustre, http://www.lustre.org/
30 * Lustre is a trademark of Sun Microsystems, Inc.
32 * lustre/lov/lov_pool.c
36 * Author: Jacques-Charles LAFOUCRIERE <jc.lafoucriere@cea.fr>
37 * Author: Alex Lyashkov <Alexey.Lyashkov@Sun.COM>
38 * Author: Nathaniel Rutman <Nathan.Rutman@Sun.COM>
41 #define DEBUG_SUBSYSTEM S_LOV
43 #include <libcfs/libcfs.h>
46 #include "lov_internal.h"
48 #define pool_tgt(_p, _i) \
49 _p->pool_lobd->u.lov.lov_tgts[_p->pool_obds.op_array[_i]]
51 static void lov_pool_getref(struct pool_desc *pool)
53 CDEBUG(D_INFO, "pool %p\n", pool);
54 atomic_inc(&pool->pool_refcount);
57 static void lov_pool_putref(struct pool_desc *pool)
59 CDEBUG(D_INFO, "pool %p\n", pool);
60 if (atomic_dec_and_test(&pool->pool_refcount)) {
61 LASSERT(hlist_unhashed(&pool->pool_hash));
62 LASSERT(list_empty(&pool->pool_list));
63 LASSERT(pool->pool_proc_entry == NULL);
64 lov_ost_pool_free(&(pool->pool_obds));
70 static void lov_pool_putref_locked(struct pool_desc *pool)
72 CDEBUG(D_INFO, "pool %p\n", pool);
73 LASSERT(atomic_read(&pool->pool_refcount) > 1);
75 atomic_dec(&pool->pool_refcount);
79 * hash function using a Rotating Hash algorithm
80 * Knuth, D. The Art of Computer Programming,
81 * Volume 3: Sorting and Searching,
83 * Addison Wesley, 1973
85 static __u32 pool_hashfn(struct cfs_hash *hash_body, const void *key,
93 poolname = (char *)key;
94 for (i = 0; i < LOV_MAXPOOLNAME; i++) {
95 if (poolname[i] == '\0')
97 result = (result << 4)^(result >> 28) ^ poolname[i];
99 return (result % mask);
102 static void *pool_key(struct hlist_node *hnode)
104 struct pool_desc *pool;
106 pool = hlist_entry(hnode, struct pool_desc, pool_hash);
107 return (pool->pool_name);
111 pool_hashkey_keycmp(const void *key, struct hlist_node *compared_hnode)
114 struct pool_desc *pool;
116 pool_name = (char *)key;
117 pool = hlist_entry(compared_hnode, struct pool_desc, pool_hash);
118 return !strncmp(pool_name, pool->pool_name, LOV_MAXPOOLNAME);
121 static void *pool_hashobject(struct hlist_node *hnode)
123 return hlist_entry(hnode, struct pool_desc, pool_hash);
126 static void pool_hashrefcount_get(struct cfs_hash *hs, struct hlist_node *hnode)
128 struct pool_desc *pool;
130 pool = hlist_entry(hnode, struct pool_desc, pool_hash);
131 lov_pool_getref(pool);
134 static void pool_hashrefcount_put_locked(struct cfs_hash *hs,
135 struct hlist_node *hnode)
137 struct pool_desc *pool;
139 pool = hlist_entry(hnode, struct pool_desc, pool_hash);
140 lov_pool_putref_locked(pool);
143 struct cfs_hash_ops pool_hash_operations = {
144 .hs_hash = pool_hashfn,
146 .hs_keycmp = pool_hashkey_keycmp,
147 .hs_object = pool_hashobject,
148 .hs_get = pool_hashrefcount_get,
149 .hs_put_locked = pool_hashrefcount_put_locked,
153 #ifdef CONFIG_PROC_FS
154 /* ifdef needed for liblustre support */
156 * pool /proc seq_file methods
159 * iterator is used to go through the target pool entries
160 * index is the current entry index in the lp_array[] array
161 * index >= pos returned to the seq_file interface
162 * pos is from 0 to (pool->pool_obds.op_count - 1)
164 #define POOL_IT_MAGIC 0xB001CEA0
165 struct pool_iterator {
167 struct pool_desc *pool;
168 int idx; /* from 0 to pool_tgt_size - 1 */
171 static void *pool_proc_next(struct seq_file *s, void *v, loff_t *pos)
173 struct pool_iterator *iter = (struct pool_iterator *)s->private;
176 LASSERTF(iter->magic == POOL_IT_MAGIC, "%08X\n", iter->magic);
178 /* test if end of file */
179 if (*pos >= pool_tgt_count(iter->pool))
182 /* iterate to find a non empty entry */
183 prev_idx = iter->idx;
184 down_read(&pool_tgt_rw_sem(iter->pool));
186 if (iter->idx == pool_tgt_count(iter->pool)) {
187 iter->idx = prev_idx; /* we stay on the last entry */
188 up_read(&pool_tgt_rw_sem(iter->pool));
191 up_read(&pool_tgt_rw_sem(iter->pool));
193 /* return != NULL to continue */
197 static void *pool_proc_start(struct seq_file *s, loff_t *pos)
199 struct pool_desc *pool = (struct pool_desc *)s->private;
200 struct pool_iterator *iter;
202 lov_pool_getref(pool);
203 if ((pool_tgt_count(pool) == 0) ||
204 (*pos >= pool_tgt_count(pool))) {
205 /* iter is not created, so stop() has no way to
206 * find pool to dec ref */
207 lov_pool_putref(pool);
213 return ERR_PTR(-ENOMEM);
214 iter->magic = POOL_IT_MAGIC;
218 /* we use seq_file private field to memorized iterator so
219 * we can free it at stop() */
220 /* /!\ do not forget to restore it to pool before freeing it */
228 ptr = pool_proc_next(s, &iter, &i);
229 } while ((i < *pos) && (ptr != NULL));
235 static void pool_proc_stop(struct seq_file *s, void *v)
237 struct pool_iterator *iter = (struct pool_iterator *)s->private;
239 /* in some cases stop() method is called 2 times, without
240 * calling start() method (see seq_read() from fs/seq_file.c)
241 * we have to free only if s->private is an iterator */
242 if ((iter) && (iter->magic == POOL_IT_MAGIC)) {
243 /* we restore s->private so next call to pool_proc_start()
245 s->private = iter->pool;
246 lov_pool_putref(iter->pool);
252 static int pool_proc_show(struct seq_file *s, void *v)
254 struct pool_iterator *iter = (struct pool_iterator *)v;
255 struct lov_tgt_desc *tgt;
257 LASSERTF(iter->magic == POOL_IT_MAGIC, "%08X\n", iter->magic);
258 LASSERT(iter->pool != NULL);
259 LASSERT(iter->idx <= pool_tgt_count(iter->pool));
261 down_read(&pool_tgt_rw_sem(iter->pool));
262 tgt = pool_tgt(iter->pool, iter->idx);
263 up_read(&pool_tgt_rw_sem(iter->pool));
265 seq_printf(s, "%s\n", obd_uuid2str(&(tgt->ltd_uuid)));
270 static struct seq_operations pool_proc_ops = {
271 .start = pool_proc_start,
272 .next = pool_proc_next,
273 .stop = pool_proc_stop,
274 .show = pool_proc_show,
277 static int pool_proc_open(struct inode *inode, struct file *file)
281 rc = seq_open(file, &pool_proc_ops);
283 struct seq_file *s = file->private_data;
284 s->private = PDE_DATA(inode);
289 static struct file_operations pool_proc_operations = {
290 .open = pool_proc_open,
293 .release = seq_release,
295 #endif /* CONFIG_PROC_FS */
297 void lov_dump_pool(int level, struct pool_desc *pool)
301 lov_pool_getref(pool);
303 CDEBUG(level, "pool "LOV_POOLNAMEF" has %d members\n",
304 pool->pool_name, pool->pool_obds.op_count);
305 down_read(&pool_tgt_rw_sem(pool));
307 for (i = 0; i < pool_tgt_count(pool) ; i++) {
308 if (!pool_tgt(pool, i) || !(pool_tgt(pool, i))->ltd_exp)
310 CDEBUG(level, "pool "LOV_POOLNAMEF"[%d] = %s\n",
312 obd_uuid2str(&((pool_tgt(pool, i))->ltd_uuid)));
315 up_read(&pool_tgt_rw_sem(pool));
316 lov_pool_putref(pool);
319 #define LOV_POOL_INIT_COUNT 2
320 int lov_ost_pool_init(struct ost_pool *op, unsigned int count)
325 count = LOV_POOL_INIT_COUNT;
328 init_rwsem(&op->op_rw_sem);
330 OBD_ALLOC(op->op_array, op->op_size * sizeof(op->op_array[0]));
331 if (op->op_array == NULL) {
339 /* Caller must hold write op_rwlock */
340 int lov_ost_pool_extend(struct ost_pool *op, unsigned int min_count)
345 LASSERT(min_count != 0);
347 if (op->op_count < op->op_size)
350 new_size = max(min_count, 2 * op->op_size);
351 OBD_ALLOC(new, new_size * sizeof(op->op_array[0]));
355 /* copy old array to new one */
356 memcpy(new, op->op_array, op->op_size * sizeof(op->op_array[0]));
357 OBD_FREE(op->op_array, op->op_size * sizeof(op->op_array[0]));
359 op->op_size = new_size;
363 int lov_ost_pool_add(struct ost_pool *op, __u32 idx, unsigned int min_count)
368 down_write(&op->op_rw_sem);
370 rc = lov_ost_pool_extend(op, min_count);
374 /* search ost in pool array */
375 for (i = 0; i < op->op_count; i++) {
376 if (op->op_array[i] == idx)
377 GOTO(out, rc = -EEXIST);
379 /* ost not found we add it */
380 op->op_array[op->op_count] = idx;
384 up_write(&op->op_rw_sem);
388 int lov_ost_pool_remove(struct ost_pool *op, __u32 idx)
393 down_write(&op->op_rw_sem);
395 for (i = 0; i < op->op_count; i++) {
396 if (op->op_array[i] == idx) {
397 memmove(&op->op_array[i], &op->op_array[i + 1],
398 (op->op_count - i - 1) * sizeof(op->op_array[0]));
400 up_write(&op->op_rw_sem);
406 up_write(&op->op_rw_sem);
410 int lov_ost_pool_free(struct ost_pool *op)
414 if (op->op_size == 0)
417 down_write(&op->op_rw_sem);
419 OBD_FREE(op->op_array, op->op_size * sizeof(op->op_array[0]));
424 up_write(&op->op_rw_sem);
429 int lov_pool_new(struct obd_device *obd, char *poolname)
432 struct pool_desc *new_pool;
438 if (strlen(poolname) > LOV_MAXPOOLNAME)
439 RETURN(-ENAMETOOLONG);
441 OBD_ALLOC_PTR(new_pool);
442 if (new_pool == NULL)
445 strlcpy(new_pool->pool_name, poolname, sizeof(new_pool->pool_name));
446 new_pool->pool_lobd = obd;
447 /* ref count init to 1 because when created a pool is always used
450 atomic_set(&new_pool->pool_refcount, 1);
451 rc = lov_ost_pool_init(&new_pool->pool_obds, 0);
455 INIT_HLIST_NODE(&new_pool->pool_hash);
457 #ifdef CONFIG_PROC_FS
458 /* get ref for /proc file */
459 lov_pool_getref(new_pool);
460 new_pool->pool_proc_entry = lprocfs_add_simple(lov->lov_pool_proc_entry,
462 &pool_proc_operations);
463 if (IS_ERR(new_pool->pool_proc_entry)) {
464 CWARN("Cannot add proc pool entry "LOV_POOLNAMEF"\n", poolname);
465 new_pool->pool_proc_entry = NULL;
466 lov_pool_putref(new_pool);
468 CDEBUG(D_INFO, "pool %p - proc %p\n",
469 new_pool, new_pool->pool_proc_entry);
472 spin_lock(&obd->obd_dev_lock);
473 list_add_tail(&new_pool->pool_list, &lov->lov_pool_list);
474 lov->lov_pool_count++;
475 spin_unlock(&obd->obd_dev_lock);
477 /* add to find only when it fully ready */
478 rc = cfs_hash_add_unique(lov->lov_pools_hash_body, poolname,
479 &new_pool->pool_hash);
481 GOTO(out_err, rc = -EEXIST);
483 CDEBUG(D_CONFIG, LOV_POOLNAMEF" is pool #%d\n",
484 poolname, lov->lov_pool_count);
489 spin_lock(&obd->obd_dev_lock);
490 list_del_init(&new_pool->pool_list);
491 lov->lov_pool_count--;
492 spin_unlock(&obd->obd_dev_lock);
493 lprocfs_remove(&new_pool->pool_proc_entry);
494 lov_ost_pool_free(&new_pool->pool_obds);
495 OBD_FREE_PTR(new_pool);
500 int lov_pool_del(struct obd_device *obd, char *poolname)
503 struct pool_desc *pool;
508 /* lookup and kill hash reference */
509 pool = cfs_hash_del_key(lov->lov_pools_hash_body, poolname);
513 if (pool->pool_proc_entry != NULL) {
514 CDEBUG(D_INFO, "proc entry %p\n", pool->pool_proc_entry);
515 lprocfs_remove(&pool->pool_proc_entry);
516 lov_pool_putref(pool);
519 spin_lock(&obd->obd_dev_lock);
520 list_del_init(&pool->pool_list);
521 lov->lov_pool_count--;
522 spin_unlock(&obd->obd_dev_lock);
524 /* release last reference */
525 lov_pool_putref(pool);
531 int lov_pool_add(struct obd_device *obd, char *poolname, char *ostname)
533 struct obd_uuid ost_uuid;
535 struct pool_desc *pool;
536 unsigned int lov_idx;
542 pool = cfs_hash_lookup(lov->lov_pools_hash_body, poolname);
546 obd_str2uuid(&ost_uuid, ostname);
549 /* search ost in lov array */
551 for (lov_idx = 0; lov_idx < lov->desc.ld_tgt_count; lov_idx++) {
552 if (!lov->lov_tgts[lov_idx])
554 if (obd_uuid_equals(&ost_uuid,
555 &(lov->lov_tgts[lov_idx]->ltd_uuid)))
558 /* test if ost found in lov */
559 if (lov_idx == lov->desc.ld_tgt_count)
560 GOTO(out, rc = -EINVAL);
562 rc = lov_ost_pool_add(&pool->pool_obds, lov_idx, lov->lov_tgt_size);
566 CDEBUG(D_CONFIG, "Added %s to "LOV_POOLNAMEF" as member %d\n",
567 ostname, poolname, pool_tgt_count(pool));
572 lov_pool_putref(pool);
576 int lov_pool_remove(struct obd_device *obd, char *poolname, char *ostname)
578 struct obd_uuid ost_uuid;
580 struct pool_desc *pool;
581 unsigned int lov_idx;
587 pool = cfs_hash_lookup(lov->lov_pools_hash_body, poolname);
591 obd_str2uuid(&ost_uuid, ostname);
594 /* search ost in lov array, to get index */
595 for (lov_idx = 0; lov_idx < lov->desc.ld_tgt_count; lov_idx++) {
596 if (!lov->lov_tgts[lov_idx])
599 if (obd_uuid_equals(&ost_uuid,
600 &(lov->lov_tgts[lov_idx]->ltd_uuid)))
604 /* test if ost found in lov */
605 if (lov_idx == lov->desc.ld_tgt_count)
606 GOTO(out, rc = -EINVAL);
608 lov_ost_pool_remove(&pool->pool_obds, lov_idx);
610 CDEBUG(D_CONFIG, "%s removed from "LOV_POOLNAMEF"\n", ostname,
616 lov_pool_putref(pool);