* 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 [sun.com URL with a
- * copy of GPLv2].
- *
- * 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.
+ * version 2 along with this program; If not, see
+ * http://www.gnu.org/licenses/gpl-2.0.html
*
* GPL HEADER END
*/
* Copyright 2008 Sun Microsystems, Inc. All rights reserved
* Use is subject to license terms.
*
- * Copyright (c) 2012, 2013, Intel Corporation.
+ * Copyright (c) 2012, 2017, Intel Corporation.
*/
/*
* This file is part of Lustre, http://www.lustre.org/
* Lustre is a trademark of Sun Microsystems, Inc.
- *
+ */
+/*
* lustre/lod/lod_pool.c
*
* OST pool methods
*
+ * This file provides code related to the Logical Object Device (LOD)
+ * handling of OST Pools on the MDT. Pools are named lists of targets
+ * that allow userspace to group targets that share a particlar property
+ * together so that users or kernel helpers can make decisions about file
+ * allocation based on these properties. For example, pools could be
+ * defined based on fault domains (e.g. separate racks of server nodes) so
+ * that RAID-1 mirroring could select targets from independent fault
+ * domains, or pools could define target performance characteristics so
+ * that applicatins could select IOP-optimized storage or stream-optimized
+ * storage for a particular output file.
+ *
+ * This file handles creation, lookup, and removal of pools themselves, as
+ * well as adding and removing targets to pools. It also handles lprocfs
+ * display of configured pool. The pools are accessed by name in the pool
+ * hash, and are refcounted to ensure proper pool structure lifetimes.
+ *
* Author: Jacques-Charles LAFOUCRIERE <jc.lafoucriere@cea.fr>
* Author: Alex Lyashkov <Alexey.Lyashkov@Sun.COM>
* Author: Nathaniel Rutman <Nathan.Rutman@Sun.COM>
#include <obd.h>
#include "lod_internal.h"
-#define pool_tgt(_p, _i) \
- OST_TGT(lu2lod_dev((_p)->pool_lobd->obd_lu_dev),(_p)->pool_obds.op_array[_i])
+#define pool_tgt(_p, _i) OST_TGT(lu2lod_dev((_p)->pool_lobd->obd_lu_dev), \
+ (_p)->pool_obds.op_array[_i])
-static void lod_pool_getref(struct pool_desc *pool)
+/**
+ * Get a reference on the specified pool.
+ *
+ * To ensure the pool descriptor is not freed before the caller is finished
+ * with it. Any process that is accessing \a pool directly needs to hold
+ * reference on it, including /proc since a userspace thread may be holding
+ * the /proc file open and busy in the kernel.
+ *
+ * \param[in] pool pool descriptor on which to gain reference
+ */
+static void pool_getref(struct pool_desc *pool)
{
CDEBUG(D_INFO, "pool %p\n", pool);
atomic_inc(&pool->pool_refcount);
}
+/**
+ * Drop a reference on the specified pool and free its memory if needed.
+ *
+ * One reference is held by the LOD OBD device while it is configured, from
+ * the time the configuration log defines the pool until the time when it is
+ * dropped when the LOD OBD is cleaned up or the pool is deleted. This means
+ * that the pool will not be freed while the LOD device is configured, unless
+ * it is explicitly destroyed by the sysadmin. The pool structure is freed
+ * after the last reference on the structure is released.
+ *
+ * \param[in] pool pool descriptor to drop reference on and possibly free
+ */
void lod_pool_putref(struct pool_desc *pool)
{
CDEBUG(D_INFO, "pool %p\n", pool);
if (atomic_dec_and_test(&pool->pool_refcount)) {
- LASSERT(cfs_hlist_unhashed(&pool->pool_hash));
- LASSERT(cfs_list_empty(&pool->pool_list));
+ LASSERT(hlist_unhashed(&pool->pool_hash));
+ LASSERT(list_empty(&pool->pool_list));
LASSERT(pool->pool_proc_entry == NULL);
lod_ost_pool_free(&(pool->pool_rr.lqr_pool));
lod_ost_pool_free(&(pool->pool_obds));
}
}
-void lod_pool_putref_locked(struct pool_desc *pool)
+/**
+ * Drop the refcount in cases where the caller holds a spinlock.
+ *
+ * This is needed if the caller cannot be blocked while freeing memory.
+ * It assumes that there is some other known refcount held on the \a pool
+ * and the memory cannot actually be freed, but the refcounting needs to
+ * be kept accurate.
+ *
+ * \param[in] pool pool descriptor on which to drop reference
+ */
+static void pool_putref_locked(struct pool_desc *pool)
{
CDEBUG(D_INFO, "pool %p\n", pool);
LASSERT(atomic_read(&pool->pool_refcount) > 1);
atomic_dec(&pool->pool_refcount);
}
-
/*
- * hash function using a Rotating Hash algorithm
- * Knuth, D. The Art of Computer Programming,
- * Volume 3: Sorting and Searching,
- * Chapter 6.4.
- * Addison Wesley, 1973
+ * Group of functions needed for cfs_hash implementation. This
+ * includes pool lookup, refcounting, and cleanup.
*/
-static __u32 pool_hashfn(cfs_hash_t *hash_body, const void *key, unsigned mask)
+
+/**
+ * Hash the pool name for use by the cfs_hash handlers.
+ *
+ * Use the standard DJB2 hash function for ASCII strings in Lustre.
+ *
+ * \param[in] hash_body hash structure where this key is embedded (unused)
+ * \param[in] key key to be hashed (in this case the pool name)
+ * \param[in] mask bitmask to limit the hash value to the desired size
+ *
+ * \retval computed hash value from \a key and limited by \a mask
+ */
+static __u32 pool_hashfn(struct cfs_hash *hash_body, const void *key,
+ unsigned mask)
{
- int i;
- __u32 result;
- char *poolname;
-
- result = 0;
- poolname = (char *)key;
- for (i = 0; i < LOV_MAXPOOLNAME; i++) {
- if (poolname[i] == '\0')
- break;
- result = (result << 4)^(result >> 28) ^ poolname[i];
- }
- return (result % mask);
+ return cfs_hash_djb2_hash(key, strnlen(key, LOV_MAXPOOLNAME), mask);
}
-static void *pool_key(cfs_hlist_node_t *hnode)
+/**
+ * Return the actual key (pool name) from the hashed \a hnode.
+ *
+ * Allows extracting the key name when iterating over all hash entries.
+ *
+ * \param[in] hnode hash node found by lookup or iteration
+ *
+ * \retval char array referencing the pool name (no refcount)
+ */
+static void *pool_key(struct hlist_node *hnode)
{
struct pool_desc *pool;
- pool = cfs_hlist_entry(hnode, struct pool_desc, pool_hash);
- return (pool->pool_name);
+ pool = hlist_entry(hnode, struct pool_desc, pool_hash);
+ return pool->pool_name;
}
-static int pool_hashkey_keycmp(const void *key, cfs_hlist_node_t *compared_hnode)
+/**
+ * Check if the specified hash key matches the hash node.
+ *
+ * This is needed in case there is a hash key collision, allowing the hash
+ * table lookup/iteration to distinguish between the two entries.
+ *
+ * \param[in] key key (pool name) being searched for
+ * \param[in] compared current entry being compared
+ *
+ * \retval 0 if \a key is the same as the key of \a compared
+ * \retval 1 if \a key is different from the key of \a compared
+ */
+static int pool_hashkey_keycmp(const void *key, struct hlist_node *compared)
{
- char *pool_name;
- struct pool_desc *pool;
-
- pool_name = (char *)key;
- pool = cfs_hlist_entry(compared_hnode, struct pool_desc, pool_hash);
- return !strncmp(pool_name, pool->pool_name, LOV_MAXPOOLNAME);
+ return !strncmp(key, pool_key(compared), LOV_MAXPOOLNAME);
}
-static void *pool_hashobject(cfs_hlist_node_t *hnode)
+/**
+ * Return the actual pool data structure from the hash table entry.
+ *
+ * Once the hash table entry is found, extract the pool data from it.
+ * The return type of this function is void * because it needs to be
+ * assigned to the generic hash operations table.
+ *
+ * \param[in] hnode hash table entry
+ *
+ * \retval struct pool_desc for the specified \a hnode
+ */
+static void *pool_hashobject(struct hlist_node *hnode)
{
- return cfs_hlist_entry(hnode, struct pool_desc, pool_hash);
+ return hlist_entry(hnode, struct pool_desc, pool_hash);
}
-static void pool_hashrefcount_get(cfs_hash_t *hs, cfs_hlist_node_t *hnode)
+static void pool_hashrefcount_get(struct cfs_hash *hs, struct hlist_node *hnode)
{
struct pool_desc *pool;
- pool = cfs_hlist_entry(hnode, struct pool_desc, pool_hash);
- lod_pool_getref(pool);
+ pool = hlist_entry(hnode, struct pool_desc, pool_hash);
+ pool_getref(pool);
}
-static void pool_hashrefcount_put_locked(cfs_hash_t *hs,
- cfs_hlist_node_t *hnode)
+static void pool_hashrefcount_put_locked(struct cfs_hash *hs,
+ struct hlist_node *hnode)
{
struct pool_desc *pool;
- pool = cfs_hlist_entry(hnode, struct pool_desc, pool_hash);
- lod_pool_putref_locked(pool);
+ pool = hlist_entry(hnode, struct pool_desc, pool_hash);
+ pool_putref_locked(pool);
}
-cfs_hash_ops_t pool_hash_operations = {
- .hs_hash = pool_hashfn,
- .hs_key = pool_key,
- .hs_keycmp = pool_hashkey_keycmp,
- .hs_object = pool_hashobject,
- .hs_get = pool_hashrefcount_get,
+struct cfs_hash_ops pool_hash_operations = {
+ .hs_hash = pool_hashfn,
+ .hs_key = pool_key,
+ .hs_keycmp = pool_hashkey_keycmp,
+ .hs_object = pool_hashobject,
+ .hs_get = pool_hashrefcount_get,
.hs_put_locked = pool_hashrefcount_put_locked,
};
-#ifdef LPROCFS
-/* ifdef needed for liblustre support */
-/*
- * pool /proc seq_file methods
- */
/*
- * iterator is used to go through the target pool entries
- * index is the current entry index in the lp_array[] array
- * index >= pos returned to the seq_file interface
- * pos is from 0 to (pool->pool_obds.op_count - 1)
+ * Methods for /proc seq_file iteration of the defined pools.
*/
+
#define POOL_IT_MAGIC 0xB001CEA0
-struct pool_iterator {
- int magic;
- struct pool_desc *pool;
- int idx; /* from 0 to pool_tgt_size - 1 */
+struct lod_pool_iterator {
+ unsigned int lpi_magic; /* POOL_IT_MAGIC */
+ unsigned int lpi_idx; /* from 0 to pool_tgt_size - 1 */
+ struct pool_desc *lpi_pool;
};
-static void *pool_proc_next(struct seq_file *s, void *v, loff_t *pos)
+/**
+ * Return the next configured target within one pool for seq_file iteration.
+ *
+ * Iterator is used to go through the target entries of a single pool
+ * (i.e. the list of OSTs configured for a named pool).
+ * lpi_idx is the current target index in the pool's op_array[].
+ *
+ * The return type is a void * because this function is one of the
+ * struct seq_operations methods and must match the function template.
+ *
+ * \param[in] seq /proc sequence file iteration tracking structure
+ * \param[in] v unused
+ * \param[in] pos position within iteration; 0 to number of targets - 1
+ *
+ * \retval struct pool_iterator of the next pool descriptor
+ */
+static void *pool_proc_next(struct seq_file *seq, void *v, loff_t *pos)
{
- struct pool_iterator *iter = (struct pool_iterator *)s->private;
+ struct lod_pool_iterator *iter = seq->private;
int prev_idx;
- LASSERTF(iter->magic == POOL_IT_MAGIC, "%08X", iter->magic);
+ LASSERTF(iter->lpi_magic == POOL_IT_MAGIC, "%08X\n", iter->lpi_magic);
/* test if end of file */
- if (*pos >= pool_tgt_count(iter->pool))
+ if (*pos >= pool_tgt_count(iter->lpi_pool))
return NULL;
+ OBD_FAIL_TIMEOUT(OBD_FAIL_OST_LIST_ASSERT, cfs_fail_val);
+
/* iterate to find a non empty entry */
- prev_idx = iter->idx;
- down_read(&pool_tgt_rw_sem(iter->pool));
- iter->idx++;
- if (iter->idx == pool_tgt_count(iter->pool)) {
- iter->idx = prev_idx; /* we stay on the last entry */
- up_read(&pool_tgt_rw_sem(iter->pool));
+ prev_idx = iter->lpi_idx;
+ iter->lpi_idx++;
+ if (iter->lpi_idx >= pool_tgt_count(iter->lpi_pool)) {
+ iter->lpi_idx = prev_idx; /* we stay on the last entry */
return NULL;
}
- up_read(&pool_tgt_rw_sem(iter->pool));
(*pos)++;
/* return != NULL to continue */
return iter;
}
-static void *pool_proc_start(struct seq_file *s, loff_t *pos)
+/**
+ * Start seq_file iteration via /proc for a single pool.
+ *
+ * The \a pos parameter may be non-zero, indicating that the iteration
+ * is starting at some offset in the target list. Use the seq_file
+ * private field to memorize the iterator so we can free it at stop().
+ * Need to restore the private pointer to the pool before freeing it.
+ *
+ * \param[in] seq new sequence file structure to initialize
+ * \param[in] pos initial target number at which to start iteration
+ *
+ * \retval initialized pool iterator private structure
+ * \retval NULL if \a pos exceeds the number of targets in \a pool
+ * \retval negative error number on failure
+ */
+static void *pool_proc_start(struct seq_file *seq, loff_t *pos)
{
- struct pool_desc *pool = (struct pool_desc *)s->private;
- struct pool_iterator *iter;
+ struct pool_desc *pool = seq->private;
+ struct lod_pool_iterator *iter;
- lod_pool_getref(pool);
+ pool_getref(pool);
if ((pool_tgt_count(pool) == 0) ||
(*pos >= pool_tgt_count(pool))) {
/* iter is not created, so stop() has no way to
}
OBD_ALLOC_PTR(iter);
- if (!iter)
+ if (iter == NULL)
return ERR_PTR(-ENOMEM);
- iter->magic = POOL_IT_MAGIC;
- iter->pool = pool;
- iter->idx = 0;
-
- /* we use seq_file private field to memorized iterator so
- * we can free it at stop() */
- /* /!\ do not forget to restore it to pool before freeing it */
- s->private = iter;
+ iter->lpi_magic = POOL_IT_MAGIC;
+ iter->lpi_pool = pool;
+ iter->lpi_idx = 0;
+
+ seq->private = iter;
+ down_read(&pool_tgt_rw_sem(pool));
if (*pos > 0) {
loff_t i;
void *ptr;
i = 0;
do {
- ptr = pool_proc_next(s, &iter, &i);
+ ptr = pool_proc_next(seq, &iter, &i);
} while ((i < *pos) && (ptr != NULL));
+
return ptr;
}
+
return iter;
}
-static void pool_proc_stop(struct seq_file *s, void *v)
+/**
+ * Finish seq_file iteration for a single pool.
+ *
+ * Once iteration has been completed, the pool_iterator struct must be
+ * freed, and the seq_file private pointer restored to the pool, as it
+ * was initially when pool_proc_start() was called.
+ *
+ * In some cases the stop() method may be called 2 times, without calling
+ * the start() method (see seq_read() from fs/seq_file.c). We have to free
+ * the private iterator struct only if seq->private points to the iterator.
+ *
+ * \param[in] seq sequence file structure to clean up
+ * \param[in] v (unused)
+ */
+static void pool_proc_stop(struct seq_file *seq, void *v)
{
- struct pool_iterator *iter = (struct pool_iterator *)s->private;
-
- /* in some cases stop() method is called 2 times, without
- * calling start() method (see seq_read() from fs/seq_file.c)
- * we have to free only if s->private is an iterator */
- if ((iter) && (iter->magic == POOL_IT_MAGIC)) {
- /* we restore s->private so next call to pool_proc_start()
- * will work */
- s->private = iter->pool;
- lod_pool_putref(iter->pool);
+ struct lod_pool_iterator *iter = seq->private;
+
+ if (iter != NULL && iter->lpi_magic == POOL_IT_MAGIC) {
+ up_read(&pool_tgt_rw_sem(iter->lpi_pool));
+ seq->private = iter->lpi_pool;
+ lod_pool_putref(iter->lpi_pool);
OBD_FREE_PTR(iter);
}
- return;
}
-static int pool_proc_show(struct seq_file *s, void *v)
+/**
+ * Print out one target entry from the pool for seq_file iteration.
+ *
+ * The currently referenced pool target is given by op_array[lpi_idx].
+ *
+ * \param[in] seq new sequence file structure to initialize
+ * \param[in] v (unused)
+ */
+static int pool_proc_show(struct seq_file *seq, void *v)
{
- struct pool_iterator *iter = (struct pool_iterator *)v;
- struct lod_tgt_desc *osc_desc;
+ struct lod_pool_iterator *iter = v;
+ struct lod_tgt_desc *tgt;
- LASSERTF(iter->magic == POOL_IT_MAGIC, "%08X", iter->magic);
- LASSERT(iter->pool != NULL);
- LASSERT(iter->idx <= pool_tgt_count(iter->pool));
+ LASSERTF(iter->lpi_magic == POOL_IT_MAGIC, "%08X\n", iter->lpi_magic);
+ LASSERT(iter->lpi_pool != NULL);
+ LASSERT(iter->lpi_idx <= pool_tgt_count(iter->lpi_pool));
- down_read(&pool_tgt_rw_sem(iter->pool));
- osc_desc = pool_tgt(iter->pool, iter->idx);
- up_read(&pool_tgt_rw_sem(iter->pool));
- if (osc_desc)
- seq_printf(s, "%s\n", obd_uuid2str(&(osc_desc->ltd_uuid)));
+ tgt = pool_tgt(iter->lpi_pool, iter->lpi_idx);
+ if (tgt != NULL)
+ seq_printf(seq, "%s\n", obd_uuid2str(&(tgt->ltd_uuid)));
return 0;
}
-static struct seq_operations pool_proc_ops = {
+static const struct seq_operations pool_proc_ops = {
.start = pool_proc_start,
.next = pool_proc_next,
.stop = pool_proc_stop,
.show = pool_proc_show,
};
+/**
+ * Open a new /proc file for seq_file iteration of targets in one pool.
+ *
+ * Initialize the seq_file private pointer to reference the pool.
+ *
+ * \param inode inode to store iteration state for /proc
+ * \param file file descriptor to store iteration methods
+ *
+ * \retval 0 for success
+ * \retval negative error number on failure
+ */
static int pool_proc_open(struct inode *inode, struct file *file)
{
int rc;
rc = seq_open(file, &pool_proc_ops);
if (!rc) {
- struct seq_file *s = file->private_data;
- s->private = PDE_DATA(inode);
+ struct seq_file *seq = file->private_data;
+ seq->private = PDE_DATA(inode);
}
return rc;
}
.llseek = seq_lseek,
.release = seq_release,
};
-#endif /* LPROCFS */
+/**
+ * Dump the pool target list into the Lustre debug log.
+ *
+ * This is a debugging function to allow dumping the list of targets
+ * in \a pool to the Lustre kernel debug log at the given \a level.
+ *
+ * This is not currently called by any existing code, but can be called
+ * from within gdb/crash to display the contents of the pool, or from
+ * code under development.
+ *
+ * \param[in] level Lustre debug level (D_INFO, D_WARN, D_ERROR, etc)
+ * \param[in] pool pool descriptor to be dumped
+ */
void lod_dump_pool(int level, struct pool_desc *pool)
{
- int i;
+ unsigned int i;
- lod_pool_getref(pool);
+ pool_getref(pool);
CDEBUG(level, "pool "LOV_POOLNAMEF" has %d members\n",
pool->pool_name, pool->pool_obds.op_count);
lod_pool_putref(pool);
}
-#define LOD_POOL_INIT_COUNT 2
+/**
+ * Initialize the pool data structures at startup.
+ *
+ * Allocate and initialize the pool data structures with the specified
+ * array size. If pool count is not specified (\a count == 0), then
+ * POOL_INIT_COUNT will be used. Allocating a non-zero initial array
+ * size avoids the need to reallocate as new pools are added.
+ *
+ * \param[in] op pool structure
+ * \param[in] count initial size of the target op_array[] array
+ *
+ * \retval 0 indicates successful pool initialization
+ * \retval negative error number on failure
+ */
+#define POOL_INIT_COUNT 2
int lod_ost_pool_init(struct ost_pool *op, unsigned int count)
{
ENTRY;
if (count == 0)
- count = LOD_POOL_INIT_COUNT;
+ count = POOL_INIT_COUNT;
op->op_array = NULL;
op->op_count = 0;
init_rwsem(&op->op_rw_sem);
- op->op_size = count;
- OBD_ALLOC(op->op_array, op->op_size * sizeof(op->op_array[0]));
+ op->op_size = count * sizeof(op->op_array[0]);
+ OBD_ALLOC(op->op_array, op->op_size);
if (op->op_array == NULL) {
op->op_size = 0;
RETURN(-ENOMEM);
return 0;
}
-/* Caller must hold write op_rwlock */
+/**
+ * Increase the op_array size to hold more targets in this pool.
+ *
+ * The size is increased to at least \a min_count, but may be larger
+ * for an existing pool since ->op_array[] is growing exponentially.
+ * Caller must hold write op_rwlock.
+ *
+ * \param[in] op pool structure
+ * \param[in] min_count minimum number of entries to handle
+ *
+ * \retval 0 on success
+ * \retval negative error number on failure.
+ */
int lod_ost_pool_extend(struct ost_pool *op, unsigned int min_count)
{
__u32 *new;
- int new_size;
+ __u32 new_size;
LASSERT(min_count != 0);
- if (op->op_count < op->op_size)
+ if (op->op_count * sizeof(op->op_array[0]) < op->op_size)
return 0;
- new_size = max(min_count, 2 * op->op_size);
- OBD_ALLOC(new, new_size * sizeof(op->op_array[0]));
+ new_size = max_t(__u32, min_count * sizeof(op->op_array[0]),
+ 2 * op->op_size);
+ OBD_ALLOC(new, new_size);
if (new == NULL)
return -ENOMEM;
/* copy old array to new one */
- memcpy(new, op->op_array, op->op_size * sizeof(op->op_array[0]));
- OBD_FREE(op->op_array, op->op_size * sizeof(op->op_array[0]));
+ memcpy(new, op->op_array, op->op_size);
+ OBD_FREE(op->op_array, op->op_size);
op->op_array = new;
op->op_size = new_size;
+
return 0;
}
+/**
+ * Add a new target to an existing pool.
+ *
+ * Add a new target device to the pool previously created and returned by
+ * lod_pool_new(). Each target can only be in each pool at most one time.
+ *
+ * \param[in] op target pool to add new entry
+ * \param[in] idx pool index number to add to the \a op array
+ * \param[in] min_count minimum number of entries to expect in the pool
+ *
+ * \retval 0 if target could be added to the pool
+ * \retval negative error if target \a idx was not added
+ */
int lod_ost_pool_add(struct ost_pool *op, __u32 idx, unsigned int min_count)
{
- int rc = 0, i;
+ unsigned int i;
+ int rc = 0;
ENTRY;
down_write(&op->op_rw_sem);
return rc;
}
+/**
+ * Remove an existing pool from the system.
+ *
+ * The specified pool must have previously been allocated by
+ * lod_pool_new() and not have any target members in the pool.
+ * If the removed target is not the last, compact the array
+ * to remove empty spaces.
+ *
+ * \param[in] op pointer to the original data structure
+ * \param[in] idx target index to be removed
+ *
+ * \retval 0 on success
+ * \retval negative error number on failure
+ */
int lod_ost_pool_remove(struct ost_pool *op, __u32 idx)
{
- int i;
+ unsigned int i;
ENTRY;
down_write(&op->op_rw_sem);
for (i = 0; i < op->op_count; i++) {
if (op->op_array[i] == idx) {
memmove(&op->op_array[i], &op->op_array[i + 1],
- (op->op_count - i - 1) * sizeof(op->op_array[0]));
+ (op->op_count - i - 1) *
+ sizeof(op->op_array[0]));
op->op_count--;
up_write(&op->op_rw_sem);
EXIT;
RETURN(-EINVAL);
}
+/**
+ * Free the pool after it was emptied and removed from /proc.
+ *
+ * Note that all of the child/target entries referenced by this pool
+ * must have been removed by lod_ost_pool_remove() before it can be
+ * deleted from memory.
+ *
+ * \param[in] op pool to be freed.
+ *
+ * \retval 0 on success or if pool was already freed
+ */
int lod_ost_pool_free(struct ost_pool *op)
{
ENTRY;
down_write(&op->op_rw_sem);
- OBD_FREE(op->op_array, op->op_size * sizeof(op->op_array[0]));
+ OBD_FREE(op->op_array, op->op_size);
op->op_array = NULL;
op->op_count = 0;
op->op_size = 0;
RETURN(0);
}
+/**
+ * Allocate a new pool for the specified device.
+ *
+ * Allocate a new pool_desc structure for the specified \a new_pool
+ * device to create a pool with the given \a poolname. The new pool
+ * structure is created with a single reference, and is freed when the
+ * reference count drops to zero.
+ *
+ * \param[in] obd Lustre OBD device on which to add a pool iterator
+ * \param[in] poolname the name of the pool to be created
+ *
+ * \retval 0 in case of success
+ * \retval negative error code in case of error
+ */
int lod_pool_new(struct obd_device *obd, char *poolname)
{
struct lod_device *lod = lu2lod_dev(obd->obd_lu_dev);
if (new_pool == NULL)
RETURN(-ENOMEM);
- strncpy(new_pool->pool_name, poolname, LOV_MAXPOOLNAME);
- new_pool->pool_name[LOV_MAXPOOLNAME] = '\0';
+ strlcpy(new_pool->pool_name, poolname, sizeof(new_pool->pool_name));
new_pool->pool_lobd = obd;
- /* ref count init to 1 because when created a pool is always used
- * up to deletion
- */
atomic_set(&new_pool->pool_refcount, 1);
rc = lod_ost_pool_init(&new_pool->pool_obds, 0);
if (rc)
GOTO(out_err, rc);
- memset(&new_pool->pool_rr, 0, sizeof(new_pool->pool_rr));
+ lu_qos_rr_init(&new_pool->pool_rr);
+
rc = lod_ost_pool_init(&new_pool->pool_rr.lqr_pool, 0);
if (rc)
GOTO(out_free_pool_obds, rc);
INIT_HLIST_NODE(&new_pool->pool_hash);
-#ifdef LPROCFS
- lod_pool_getref(new_pool);
+#ifdef CONFIG_PROC_FS
+ pool_getref(new_pool);
new_pool->pool_proc_entry = lprocfs_add_simple(lod->lod_pool_proc_entry,
- poolname,
-#ifndef HAVE_ONLY_PROCFS_SEQ
- NULL, NULL,
-#endif
- new_pool,
+ poolname, new_pool,
&pool_proc_operations);
if (IS_ERR(new_pool->pool_proc_entry)) {
- CWARN("Cannot add proc pool entry "LOV_POOLNAMEF"\n", poolname);
+ CDEBUG(D_CONFIG, "%s: cannot add proc entry "LOV_POOLNAMEF"\n",
+ obd->obd_name, poolname);
new_pool->pool_proc_entry = NULL;
lod_pool_putref(new_pool);
}
- CDEBUG(D_INFO, "pool %p - proc %p\n", new_pool, new_pool->pool_proc_entry);
+ CDEBUG(D_INFO, "pool %p - proc %p\n", new_pool,
+ new_pool->pool_proc_entry);
#endif
spin_lock(&obd->obd_dev_lock);
- cfs_list_add_tail(&new_pool->pool_list, &lod->lod_pool_list);
+ list_add_tail(&new_pool->pool_list, &lod->lod_pool_list);
lod->lod_pool_count++;
spin_unlock(&obd->obd_dev_lock);
out_err:
spin_lock(&obd->obd_dev_lock);
- cfs_list_del_init(&new_pool->pool_list);
+ list_del_init(&new_pool->pool_list);
lod->lod_pool_count--;
spin_unlock(&obd->obd_dev_lock);
return rc;
}
+/**
+ * Remove the named pool from the OBD device.
+ *
+ * \param[in] obd OBD device on which pool was previously created
+ * \param[in] poolname name of pool to remove from \a obd
+ *
+ * \retval 0 on successfully removing the pool
+ * \retval negative error numbers for failures
+ */
int lod_pool_del(struct obd_device *obd, char *poolname)
{
struct lod_device *lod = lu2lod_dev(obd->obd_lu_dev);
}
spin_lock(&obd->obd_dev_lock);
- cfs_list_del_init(&pool->pool_list);
+ list_del_init(&pool->pool_list);
lod->lod_pool_count--;
spin_unlock(&obd->obd_dev_lock);
RETURN(0);
}
-
+/**
+ * Add a single target device to the named pool.
+ *
+ * Add the target specified by \a ostname to the specified \a poolname.
+ *
+ * \param[in] obd OBD device on which to add the pool
+ * \param[in] poolname name of the pool to which to add the target \a ostname
+ * \param[in] ostname name of the target device to be added
+ *
+ * \retval 0 if \a ostname was (previously) added to the named pool
+ * \retval negative error number on failure
+ */
int lod_pool_add(struct obd_device *obd, char *poolname, char *ostname)
{
- struct lod_device *lod = lu2lod_dev(obd->obd_lu_dev);
- struct obd_uuid ost_uuid;
- struct pool_desc *pool;
- unsigned int idx;
- int rc = -EINVAL;
+ struct lod_device *lod = lu2lod_dev(obd->obd_lu_dev);
+ struct obd_uuid ost_uuid;
+ struct pool_desc *pool;
+ unsigned int idx;
+ int rc = -EINVAL;
ENTRY;
pool = cfs_hash_lookup(lod->lod_pools_hash_body, poolname);
return rc;
}
+/**
+ * Remove the named target from the specified pool.
+ *
+ * Remove one target named \a ostname from \a poolname. The \a ostname
+ * is searched for in the lod_device lod_ost_bitmap array, to ensure the
+ * specified name actually exists in the pool.
+ *
+ * \param[in] obd OBD device from which to remove \a poolname
+ * \param[in] poolname name of the pool to be changed
+ * \param[in] ostname name of the target to remove from \a poolname
+ *
+ * \retval 0 on successfully removing \a ostname from the pool
+ * \retval negative number on error (e.g. \a ostname not in pool)
+ */
int lod_pool_remove(struct obd_device *obd, char *poolname, char *ostname)
{
- struct lod_device *lod = lu2lod_dev(obd->obd_lu_dev);
- struct obd_uuid ost_uuid;
- struct pool_desc *pool;
- unsigned int idx;
- int rc = -EINVAL;
+ struct lod_device *lod = lu2lod_dev(obd->obd_lu_dev);
+ struct obd_uuid ost_uuid;
+ struct pool_desc *pool;
+ unsigned int idx;
+ int rc = -EINVAL;
ENTRY;
pool = cfs_hash_lookup(lod->lod_pools_hash_body, poolname);
obd_str2uuid(&ost_uuid, ostname);
lod_getref(&lod->lod_ost_descs);
- /* search ost in lod array, to get index */
cfs_foreach_bit(lod->lod_ost_bitmap, idx) {
if (obd_uuid_equals(&ost_uuid, &OST_TGT(lod, idx)->ltd_uuid)) {
rc = 0;
return rc;
}
+/**
+ * Check if the specified target exists in the pool.
+ *
+ * The caller may not have a reference on \a pool if it got the pool without
+ * calling lod_find_pool() (e.g. directly from the lod pool list)
+ *
+ * \param[in] idx Target index to check
+ * \param[in] pool Pool in which to check if target is added.
+ *
+ * \retval 0 successfully found index in \a pool
+ * \retval negative error if device not found in \a pool
+ */
int lod_check_index_in_pool(__u32 idx, struct pool_desc *pool)
{
- int i, rc;
+ unsigned int i;
+ int rc;
ENTRY;
- /* caller may no have a ref on pool if it got the pool
- * without calling lod_find_pool() (e.g. go through the lod pool
- * list)
- */
- lod_pool_getref(pool);
+ pool_getref(pool);
down_read(&pool_tgt_rw_sem(pool));
return rc;
}
+/**
+ * Find the pool descriptor for the specified pool and return it with a
+ * reference to the caller if found.
+ *
+ * \param[in] lod LOD on which the pools are configured
+ * \param[in] poolname NUL-terminated name of the pool
+ *
+ * \retval pointer to pool descriptor on success
+ * \retval NULL if \a poolname could not be found or poolname is empty
+ */
struct pool_desc *lod_find_pool(struct lod_device *lod, char *poolname)
{
struct pool_desc *pool;
if (poolname[0] != '\0') {
pool = cfs_hash_lookup(lod->lod_pools_hash_body, poolname);
if (pool == NULL)
- CWARN("Request for an unknown pool ("LOV_POOLNAMEF")\n",
- poolname);
- if ((pool != NULL) && (pool_tgt_count(pool) == 0)) {
- CWARN("Request for an empty pool ("LOV_POOLNAMEF")\n",
- poolname);
+ CDEBUG(D_CONFIG, "%s: request for an unknown pool ("
+ LOV_POOLNAMEF")\n",
+ lod->lod_child_exp->exp_obd->obd_name, poolname);
+ if (pool != NULL && pool_tgt_count(pool) == 0) {
+ CDEBUG(D_CONFIG, "%s: request for an empty pool ("
+ LOV_POOLNAMEF")\n",
+ lod->lod_child_exp->exp_obd->obd_name, poolname);
/* pool is ignored, so we remove ref on it */
lod_pool_putref(pool);
pool = NULL;