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 2008 Sun Microsystems, Inc. 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.
33 * lustre/lod/lod_pool.c
37 * This file provides code related to the Logical Object Device (LOD)
38 * handling of OST Pools on the MDT. Pools are named lists of targets
39 * that allow userspace to group targets that share a particlar property
40 * together so that users or kernel helpers can make decisions about file
41 * allocation based on these properties. For example, pools could be
42 * defined based on fault domains (e.g. separate racks of server nodes) so
43 * that RAID-1 mirroring could select targets from independent fault
44 * domains, or pools could define target performance characteristics so
45 * that applicatins could select IOP-optimized storage or stream-optimized
46 * storage for a particular output file.
48 * This file handles creation, lookup, and removal of pools themselves, as
49 * well as adding and removing targets to pools. It also handles lprocfs
50 * display of configured pool. The pools are accessed by name in the pool
51 * hash, and are refcounted to ensure proper pool structure lifetimes.
53 * Author: Jacques-Charles LAFOUCRIERE <jc.lafoucriere@cea.fr>
54 * Author: Alex Lyashkov <Alexey.Lyashkov@Sun.COM>
55 * Author: Nathaniel Rutman <Nathan.Rutman@Sun.COM>
58 #define DEBUG_SUBSYSTEM S_LOV
60 #include <libcfs/libcfs.h>
62 #include "lod_internal.h"
64 #define pool_tgt(_p, _i) OST_TGT(lu2lod_dev((_p)->pool_lobd->obd_lu_dev), \
65 (_p)->pool_obds.op_array[_i])
68 * Get a reference on the specified pool.
70 * To ensure the pool descriptor is not freed before the caller is finished
71 * with it. Any process that is accessing \a pool directly needs to hold
72 * reference on it, including /proc since a userspace thread may be holding
73 * the /proc file open and busy in the kernel.
75 * \param[in] pool pool descriptor on which to gain reference
77 static void pool_getref(struct pool_desc *pool)
79 CDEBUG(D_INFO, "pool %p\n", pool);
80 atomic_inc(&pool->pool_refcount);
84 * Drop a reference on the specified pool and free its memory if needed.
86 * One reference is held by the LOD OBD device while it is configured, from
87 * the time the configuration log defines the pool until the time when it is
88 * dropped when the LOD OBD is cleaned up or the pool is deleted. This means
89 * that the pool will not be freed while the LOD device is configured, unless
90 * it is explicitly destroyed by the sysadmin. The pool structure is freed
91 * after the last reference on the structure is released.
93 * \param[in] pool pool descriptor to drop reference on and possibly free
95 void lod_pool_putref(struct pool_desc *pool)
97 CDEBUG(D_INFO, "pool %p\n", pool);
98 if (atomic_dec_and_test(&pool->pool_refcount)) {
99 LASSERT(hlist_unhashed(&pool->pool_hash));
100 LASSERT(list_empty(&pool->pool_list));
101 LASSERT(pool->pool_proc_entry == NULL);
102 lod_ost_pool_free(&(pool->pool_rr.lqr_pool));
103 lod_ost_pool_free(&(pool->pool_obds));
110 * Drop the refcount in cases where the caller holds a spinlock.
112 * This is needed if the caller cannot be blocked while freeing memory.
113 * It assumes that there is some other known refcount held on the \a pool
114 * and the memory cannot actually be freed, but the refcounting needs to
117 * \param[in] pool pool descriptor on which to drop reference
119 static void pool_putref_locked(struct pool_desc *pool)
121 CDEBUG(D_INFO, "pool %p\n", pool);
122 LASSERT(atomic_read(&pool->pool_refcount) > 1);
124 atomic_dec(&pool->pool_refcount);
128 * Group of functions needed for cfs_hash implementation. This
129 * includes pool lookup, refcounting, and cleanup.
133 * Hash the pool name for use by the cfs_hash handlers.
135 * Use the standard DJB2 hash function for ASCII strings in Lustre.
137 * \param[in] hash_body hash structure where this key is embedded (unused)
138 * \param[in] key key to be hashed (in this case the pool name)
139 * \param[in] mask bitmask to limit the hash value to the desired size
141 * \retval computed hash value from \a key and limited by \a mask
143 static __u32 pool_hashfn(cfs_hash_t *hash_body, const void *key, unsigned mask)
145 return cfs_hash_djb2_hash(key, strnlen(key, LOV_MAXPOOLNAME), mask);
149 * Return the actual key (pool name) from the hashed \a hnode.
151 * Allows extracting the key name when iterating over all hash entries.
153 * \param[in] hnode hash node found by lookup or iteration
155 * \retval char array referencing the pool name (no refcount)
157 static void *pool_key(struct hlist_node *hnode)
159 struct pool_desc *pool;
161 pool = hlist_entry(hnode, struct pool_desc, pool_hash);
162 return pool->pool_name;
166 * Check if the specified hash key matches the hash node.
168 * This is needed in case there is a hash key collision, allowing the hash
169 * table lookup/iteration to distinguish between the two entries.
171 * \param[in] key key (pool name) being searched for
172 * \param[in] compared current entry being compared
174 * \retval 0 if \a key is the same as the key of \a compared
175 * \retval 1 if \a key is different from the key of \a compared
177 static int pool_hashkey_keycmp(const void *key, struct hlist_node *compared)
179 return !strncmp(key, pool_key(compared), LOV_MAXPOOLNAME);
183 * Return the actual pool data structure from the hash table entry.
185 * Once the hash table entry is found, extract the pool data from it.
186 * The return type of this function is void * because it needs to be
187 * assigned to the generic hash operations table.
189 * \param[in] hnode hash table entry
191 * \retval struct pool_desc for the specified \a hnode
193 static void *pool_hashobject(struct hlist_node *hnode)
195 return hlist_entry(hnode, struct pool_desc, pool_hash);
198 static void pool_hashrefcount_get(cfs_hash_t *hs, struct hlist_node *hnode)
200 struct pool_desc *pool;
202 pool = hlist_entry(hnode, struct pool_desc, pool_hash);
206 static void pool_hashrefcount_put_locked(cfs_hash_t *hs,
207 struct hlist_node *hnode)
209 struct pool_desc *pool;
211 pool = hlist_entry(hnode, struct pool_desc, pool_hash);
212 pool_putref_locked(pool);
215 cfs_hash_ops_t pool_hash_operations = {
216 .hs_hash = pool_hashfn,
218 .hs_keycmp = pool_hashkey_keycmp,
219 .hs_object = pool_hashobject,
220 .hs_get = pool_hashrefcount_get,
221 .hs_put_locked = pool_hashrefcount_put_locked,
225 * Methods for /proc seq_file iteration of the defined pools.
228 #define POOL_IT_MAGIC 0xB001CEA0
229 struct lod_pool_iterator {
230 unsigned int lpi_magic; /* POOL_IT_MAGIC */
231 unsigned int lpi_idx; /* from 0 to pool_tgt_size - 1 */
232 struct pool_desc *lpi_pool;
236 * Return the next configured target within one pool for seq_file iteration.
238 * Iterator is used to go through the target entries of a single pool
239 * (i.e. the list of OSTs configured for a named pool).
240 * lpi_idx is the current target index in the pool's op_array[].
242 * The return type is a void * because this function is one of the
243 * struct seq_operations methods and must match the function template.
245 * \param[in] seq /proc sequence file iteration tracking structure
246 * \param[in] v unused
247 * \param[in] pos position within iteration; 0 to number of targets - 1
249 * \retval struct pool_iterator of the next pool descriptor
251 static void *pool_proc_next(struct seq_file *seq, void *v, loff_t *pos)
253 struct lod_pool_iterator *iter = seq->private;
256 LASSERTF(iter->lpi_magic == POOL_IT_MAGIC, "%08X\n", iter->lpi_magic);
258 /* test if end of file */
259 if (*pos >= pool_tgt_count(iter->lpi_pool))
262 /* iterate to find a non empty entry */
263 prev_idx = iter->lpi_idx;
264 down_read(&pool_tgt_rw_sem(iter->lpi_pool));
266 if (iter->lpi_idx == pool_tgt_count(iter->lpi_pool)) {
267 iter->lpi_idx = prev_idx; /* we stay on the last entry */
268 up_read(&pool_tgt_rw_sem(iter->lpi_pool));
271 up_read(&pool_tgt_rw_sem(iter->lpi_pool));
273 /* return != NULL to continue */
278 * Start seq_file iteration via /proc for a single pool.
280 * The \a pos parameter may be non-zero, indicating that the iteration
281 * is starting at some offset in the target list. Use the seq_file
282 * private field to memorize the iterator so we can free it at stop().
283 * Need to restore the private pointer to the pool before freeing it.
285 * \param[in] seq new sequence file structure to initialize
286 * \param[in] pos initial target number at which to start iteration
288 * \retval initialized pool iterator private structure
289 * \retval NULL if \a pos exceeds the number of targets in \a pool
290 * \retval negative error number on failure
292 static void *pool_proc_start(struct seq_file *seq, loff_t *pos)
294 struct pool_desc *pool = seq->private;
295 struct lod_pool_iterator *iter;
298 if ((pool_tgt_count(pool) == 0) ||
299 (*pos >= pool_tgt_count(pool))) {
300 /* iter is not created, so stop() has no way to
301 * find pool to dec ref */
302 lod_pool_putref(pool);
308 return ERR_PTR(-ENOMEM);
309 iter->lpi_magic = POOL_IT_MAGIC;
310 iter->lpi_pool = pool;
320 ptr = pool_proc_next(seq, &iter, &i);
321 } while ((i < *pos) && (ptr != NULL));
330 * Finish seq_file iteration for a single pool.
332 * Once iteration has been completed, the pool_iterator struct must be
333 * freed, and the seq_file private pointer restored to the pool, as it
334 * was initially when pool_proc_start() was called.
336 * In some cases the stop() method may be called 2 times, without calling
337 * the start() method (see seq_read() from fs/seq_file.c). We have to free
338 * the private iterator struct only if seq->private points to the iterator.
340 * \param[in] seq sequence file structure to clean up
341 * \param[in] v (unused)
343 static void pool_proc_stop(struct seq_file *seq, void *v)
345 struct lod_pool_iterator *iter = seq->private;
347 if (iter != NULL && iter->lpi_magic == POOL_IT_MAGIC) {
348 seq->private = iter->lpi_pool;
349 lod_pool_putref(iter->lpi_pool);
355 * Print out one target entry from the pool for seq_file iteration.
357 * The currently referenced pool target is given by op_array[lpi_idx].
359 * \param[in] seq new sequence file structure to initialize
360 * \param[in] v (unused)
362 static int pool_proc_show(struct seq_file *seq, void *v)
364 struct lod_pool_iterator *iter = v;
365 struct lod_tgt_desc *tgt;
367 LASSERTF(iter->lpi_magic == POOL_IT_MAGIC, "%08X\n", iter->lpi_magic);
368 LASSERT(iter->lpi_pool != NULL);
369 LASSERT(iter->lpi_idx <= pool_tgt_count(iter->lpi_pool));
371 down_read(&pool_tgt_rw_sem(iter->lpi_pool));
372 tgt = pool_tgt(iter->lpi_pool, iter->lpi_idx);
373 up_read(&pool_tgt_rw_sem(iter->lpi_pool));
375 seq_printf(seq, "%s\n", obd_uuid2str(&(tgt->ltd_uuid)));
380 static const struct seq_operations pool_proc_ops = {
381 .start = pool_proc_start,
382 .next = pool_proc_next,
383 .stop = pool_proc_stop,
384 .show = pool_proc_show,
388 * Open a new /proc file for seq_file iteration of targets in one pool.
390 * Initialize the seq_file private pointer to reference the pool.
392 * \param inode inode to store iteration state for /proc
393 * \param file file descriptor to store iteration methods
395 * \retval 0 for success
396 * \retval negative error number on failure
398 static int pool_proc_open(struct inode *inode, struct file *file)
402 rc = seq_open(file, &pool_proc_ops);
404 struct seq_file *seq = file->private_data;
405 seq->private = PDE_DATA(inode);
410 static struct file_operations pool_proc_operations = {
411 .open = pool_proc_open,
414 .release = seq_release,
418 * Dump the pool target list into the Lustre debug log.
420 * This is a debugging function to allow dumping the list of targets
421 * in \a pool to the Lustre kernel debug log at the given \a level.
423 * This is not currently called by any existing code, but can be called
424 * from within gdb/crash to display the contents of the pool, or from
425 * code under development.
427 * \param[in] level Lustre debug level (D_INFO, D_WARN, D_ERROR, etc)
428 * \param[in] pool pool descriptor to be dumped
430 void lod_dump_pool(int level, struct pool_desc *pool)
436 CDEBUG(level, "pool "LOV_POOLNAMEF" has %d members\n",
437 pool->pool_name, pool->pool_obds.op_count);
438 down_read(&pool_tgt_rw_sem(pool));
440 for (i = 0; i < pool_tgt_count(pool) ; i++) {
441 if (!pool_tgt(pool, i) || !(pool_tgt(pool, i))->ltd_exp)
443 CDEBUG(level, "pool "LOV_POOLNAMEF"[%d] = %s\n",
445 obd_uuid2str(&((pool_tgt(pool, i))->ltd_uuid)));
448 up_read(&pool_tgt_rw_sem(pool));
449 lod_pool_putref(pool);
453 * Initialize the pool data structures at startup.
455 * Allocate and initialize the pool data structures with the specified
456 * array size. If pool count is not specified (\a count == 0), then
457 * POOL_INIT_COUNT will be used. Allocating a non-zero initial array
458 * size avoids the need to reallocate as new pools are added.
460 * \param[in] op pool structure
461 * \param[in] count initial size of the target op_array[] array
463 * \retval 0 indicates successful pool initialization
464 * \retval negative error number on failure
466 #define POOL_INIT_COUNT 2
467 int lod_ost_pool_init(struct ost_pool *op, unsigned int count)
472 count = POOL_INIT_COUNT;
475 init_rwsem(&op->op_rw_sem);
477 OBD_ALLOC(op->op_array, op->op_size * sizeof(op->op_array[0]));
478 if (op->op_array == NULL) {
487 * Increase the op_array size to hold more targets in this pool.
489 * The size is increased to at least \a min_count, but may be larger
490 * for an existing pool since ->op_array[] is growing exponentially.
491 * Caller must hold write op_rwlock.
493 * \param[in] op pool structure
494 * \param[in] min_count minimum number of entries to handle
496 * \retval 0 on success
497 * \retval negative error number on failure.
499 int lod_ost_pool_extend(struct ost_pool *op, unsigned int min_count)
504 LASSERT(min_count != 0);
506 if (op->op_count < op->op_size)
509 new_size = max(min_count, 2 * op->op_size);
510 OBD_ALLOC(new, new_size * sizeof(op->op_array[0]));
514 /* copy old array to new one */
515 memcpy(new, op->op_array, op->op_size * sizeof(op->op_array[0]));
516 OBD_FREE(op->op_array, op->op_size * sizeof(op->op_array[0]));
518 op->op_size = new_size;
524 * Add a new target to an existing pool.
526 * Add a new target device to the pool previously created and returned by
527 * lod_pool_new(). Each target can only be in each pool at most one time.
529 * \param[in] op target pool to add new entry
530 * \param[in] idx pool index number to add to the \a op array
531 * \param[in] min_count minimum number of entries to expect in the pool
533 * \retval 0 if target could be added to the pool
534 * \retval negative error if target \a idx was not added
536 int lod_ost_pool_add(struct ost_pool *op, __u32 idx, unsigned int min_count)
542 down_write(&op->op_rw_sem);
544 rc = lod_ost_pool_extend(op, min_count);
548 /* search ost in pool array */
549 for (i = 0; i < op->op_count; i++) {
550 if (op->op_array[i] == idx)
551 GOTO(out, rc = -EEXIST);
553 /* ost not found we add it */
554 op->op_array[op->op_count] = idx;
558 up_write(&op->op_rw_sem);
563 * Remove an existing pool from the system.
565 * The specified pool must have previously been allocated by
566 * lod_pool_new() and not have any target members in the pool.
567 * If the removed target is not the last, compact the array
568 * to remove empty spaces.
570 * \param[in] op pointer to the original data structure
571 * \param[in] idx target index to be removed
573 * \retval 0 on success
574 * \retval negative error number on failure
576 int lod_ost_pool_remove(struct ost_pool *op, __u32 idx)
581 down_write(&op->op_rw_sem);
583 for (i = 0; i < op->op_count; i++) {
584 if (op->op_array[i] == idx) {
585 memmove(&op->op_array[i], &op->op_array[i + 1],
586 (op->op_count - i - 1) *
587 sizeof(op->op_array[0]));
589 up_write(&op->op_rw_sem);
595 up_write(&op->op_rw_sem);
600 * Free the pool after it was emptied and removed from /proc.
602 * Note that all of the child/target entries referenced by this pool
603 * must have been removed by lod_ost_pool_remove() before it can be
604 * deleted from memory.
606 * \param[in] op pool to be freed.
608 * \retval 0 on success or if pool was already freed
610 int lod_ost_pool_free(struct ost_pool *op)
614 if (op->op_size == 0)
617 down_write(&op->op_rw_sem);
619 OBD_FREE(op->op_array, op->op_size * sizeof(op->op_array[0]));
624 up_write(&op->op_rw_sem);
629 * Allocate a new pool for the specified device.
631 * Allocate a new pool_desc structure for the specified \a new_pool
632 * device to create a pool with the given \a poolname. The new pool
633 * structure is created with a single reference, and is freed when the
634 * reference count drops to zero.
636 * \param[in] obd Lustre OBD device on which to add a pool iterator
637 * \param[in] poolname the name of the pool to be created
639 * \retval 0 in case of success
640 * \retval negative error code in case of error
642 int lod_pool_new(struct obd_device *obd, char *poolname)
644 struct lod_device *lod = lu2lod_dev(obd->obd_lu_dev);
645 struct pool_desc *new_pool;
649 if (strlen(poolname) > LOV_MAXPOOLNAME)
650 RETURN(-ENAMETOOLONG);
652 OBD_ALLOC_PTR(new_pool);
653 if (new_pool == NULL)
656 strlcpy(new_pool->pool_name, poolname, sizeof(new_pool->pool_name));
657 new_pool->pool_lobd = obd;
658 atomic_set(&new_pool->pool_refcount, 1);
659 rc = lod_ost_pool_init(&new_pool->pool_obds, 0);
663 memset(&new_pool->pool_rr, 0, sizeof(new_pool->pool_rr));
664 rc = lod_ost_pool_init(&new_pool->pool_rr.lqr_pool, 0);
666 GOTO(out_free_pool_obds, rc);
668 INIT_HLIST_NODE(&new_pool->pool_hash);
671 pool_getref(new_pool);
672 new_pool->pool_proc_entry = lprocfs_add_simple(lod->lod_pool_proc_entry,
674 &pool_proc_operations);
675 if (IS_ERR(new_pool->pool_proc_entry)) {
676 CDEBUG(D_CONFIG, "%s: cannot add proc entry "LOV_POOLNAMEF"\n",
677 obd->obd_name, poolname);
678 new_pool->pool_proc_entry = NULL;
679 lod_pool_putref(new_pool);
681 CDEBUG(D_INFO, "pool %p - proc %p\n", new_pool,
682 new_pool->pool_proc_entry);
685 spin_lock(&obd->obd_dev_lock);
686 list_add_tail(&new_pool->pool_list, &lod->lod_pool_list);
687 lod->lod_pool_count++;
688 spin_unlock(&obd->obd_dev_lock);
690 /* add to find only when it fully ready */
691 rc = cfs_hash_add_unique(lod->lod_pools_hash_body, poolname,
692 &new_pool->pool_hash);
694 GOTO(out_err, rc = -EEXIST);
696 CDEBUG(D_CONFIG, LOV_POOLNAMEF" is pool #%d\n",
697 poolname, lod->lod_pool_count);
702 spin_lock(&obd->obd_dev_lock);
703 list_del_init(&new_pool->pool_list);
704 lod->lod_pool_count--;
705 spin_unlock(&obd->obd_dev_lock);
707 lprocfs_remove(&new_pool->pool_proc_entry);
709 lod_ost_pool_free(&new_pool->pool_rr.lqr_pool);
711 lod_ost_pool_free(&new_pool->pool_obds);
712 OBD_FREE_PTR(new_pool);
717 * Remove the named pool from the OBD device.
719 * \param[in] obd OBD device on which pool was previously created
720 * \param[in] poolname name of pool to remove from \a obd
722 * \retval 0 on successfully removing the pool
723 * \retval negative error numbers for failures
725 int lod_pool_del(struct obd_device *obd, char *poolname)
727 struct lod_device *lod = lu2lod_dev(obd->obd_lu_dev);
728 struct pool_desc *pool;
731 /* lookup and kill hash reference */
732 pool = cfs_hash_del_key(lod->lod_pools_hash_body, poolname);
736 if (pool->pool_proc_entry != NULL) {
737 CDEBUG(D_INFO, "proc entry %p\n", pool->pool_proc_entry);
738 lprocfs_remove(&pool->pool_proc_entry);
739 lod_pool_putref(pool);
742 spin_lock(&obd->obd_dev_lock);
743 list_del_init(&pool->pool_list);
744 lod->lod_pool_count--;
745 spin_unlock(&obd->obd_dev_lock);
747 /* release last reference */
748 lod_pool_putref(pool);
754 * Add a single target device to the named pool.
756 * Add the target specified by \a ostname to the specified \a poolname.
758 * \param[in] obd OBD device on which to add the pool
759 * \param[in] poolname name of the pool to which to add the target \a ostname
760 * \param[in] ostname name of the target device to be added
762 * \retval 0 if \a ostname was (previously) added to the named pool
763 * \retval negative error number on failure
765 int lod_pool_add(struct obd_device *obd, char *poolname, char *ostname)
767 struct lod_device *lod = lu2lod_dev(obd->obd_lu_dev);
768 struct obd_uuid ost_uuid;
769 struct pool_desc *pool;
774 pool = cfs_hash_lookup(lod->lod_pools_hash_body, poolname);
778 obd_str2uuid(&ost_uuid, ostname);
780 /* search ost in lod array */
781 lod_getref(&lod->lod_ost_descs);
782 lod_foreach_ost(lod, idx) {
783 if (obd_uuid_equals(&ost_uuid, &OST_TGT(lod, idx)->ltd_uuid)) {
792 rc = lod_ost_pool_add(&pool->pool_obds, idx, lod->lod_osts_size);
796 pool->pool_rr.lqr_dirty = 1;
798 CDEBUG(D_CONFIG, "Added %s to "LOV_POOLNAMEF" as member %d\n",
799 ostname, poolname, pool_tgt_count(pool));
803 lod_putref(lod, &lod->lod_ost_descs);
804 lod_pool_putref(pool);
809 * Remove the named target from the specified pool.
811 * Remove one target named \a ostname from \a poolname. The \a ostname
812 * is searched for in the lod_device lod_ost_bitmap array, to ensure the
813 * specified name actually exists in the pool.
815 * \param[in] obd OBD device from which to remove \a poolname
816 * \param[in] poolname name of the pool to be changed
817 * \param[in] ostname name of the target to remove from \a poolname
819 * \retval 0 on successfully removing \a ostname from the pool
820 * \retval negative number on error (e.g. \a ostname not in pool)
822 int lod_pool_remove(struct obd_device *obd, char *poolname, char *ostname)
824 struct lod_device *lod = lu2lod_dev(obd->obd_lu_dev);
825 struct obd_uuid ost_uuid;
826 struct pool_desc *pool;
831 pool = cfs_hash_lookup(lod->lod_pools_hash_body, poolname);
835 obd_str2uuid(&ost_uuid, ostname);
837 lod_getref(&lod->lod_ost_descs);
838 cfs_foreach_bit(lod->lod_ost_bitmap, idx) {
839 if (obd_uuid_equals(&ost_uuid, &OST_TGT(lod, idx)->ltd_uuid)) {
845 /* test if ost found in lod array */
849 lod_ost_pool_remove(&pool->pool_obds, idx);
851 pool->pool_rr.lqr_dirty = 1;
853 CDEBUG(D_CONFIG, "%s removed from "LOV_POOLNAMEF"\n", ostname,
858 lod_putref(lod, &lod->lod_ost_descs);
859 lod_pool_putref(pool);
864 * Check if the specified target exists in the pool.
866 * The caller may not have a reference on \a pool if it got the pool without
867 * calling lod_find_pool() (e.g. directly from the lod pool list)
869 * \param[in] idx Target index to check
870 * \param[in] pool Pool in which to check if target is added.
872 * \retval 0 successfully found index in \a pool
873 * \retval negative error if device not found in \a pool
875 int lod_check_index_in_pool(__u32 idx, struct pool_desc *pool)
883 down_read(&pool_tgt_rw_sem(pool));
885 for (i = 0; i < pool_tgt_count(pool); i++) {
886 if (pool_tgt_array(pool)[i] == idx)
892 up_read(&pool_tgt_rw_sem(pool));
894 lod_pool_putref(pool);
899 * Find the pool descriptor for the specified pool and return it with a
900 * reference to the caller if found.
902 * \param[in] lod LOD on which the pools are configured
903 * \param[in] poolname NUL-terminated name of the pool
905 * \retval pointer to pool descriptor on success
906 * \retval NULL if \a poolname could not be found or poolname is empty
908 struct pool_desc *lod_find_pool(struct lod_device *lod, char *poolname)
910 struct pool_desc *pool;
913 if (poolname[0] != '\0') {
914 pool = cfs_hash_lookup(lod->lod_pools_hash_body, poolname);
916 CDEBUG(D_CONFIG, "%s: request for an unknown pool ("
918 lod->lod_child_exp->exp_obd->obd_name, poolname);
919 if (pool != NULL && pool_tgt_count(pool) == 0) {
920 CDEBUG(D_CONFIG, "%s: request for an empty pool ("
922 lod->lod_child_exp->exp_obd->obd_name, poolname);
923 /* pool is ignored, so we remove ref on it */
924 lod_pool_putref(pool);