diff options
Diffstat (limited to 'xlators/storage/bdb/src/bctx.c')
| -rw-r--r-- | xlators/storage/bdb/src/bctx.c | 394 |
1 files changed, 394 insertions, 0 deletions
diff --git a/xlators/storage/bdb/src/bctx.c b/xlators/storage/bdb/src/bctx.c new file mode 100644 index 000000000..2bfa3ea87 --- /dev/null +++ b/xlators/storage/bdb/src/bctx.c @@ -0,0 +1,394 @@ +/* + Copyright (c) 2008 Z RESEARCH, Inc. <http://www.zresearch.com> + This file is part of GlusterFS. + + GlusterFS is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published + by the Free Software Foundation; either version 3 of the License, + or (at your option) any later version. + + GlusterFS 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 for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see + <http://www.gnu.org/licenses/>. +*/ + +#include <list.h> +#include <bdb.h> +#include <libgen.h> /* for dirname */ + +static void +__destroy_bctx (bctx_t *bctx) +{ + if (bctx->directory) + FREE (bctx->directory); + + if (bctx->db_path) + FREE (bctx->db_path); + + FREE (bctx); +} + +static void +__unhash_bctx (bctx_t *bctx) +{ + list_del_init (&bctx->b_hash); +} + +static int32_t +bctx_table_prune (bctx_table_t *table) +{ + int32_t ret = 0; + struct list_head purge = {0,}; + struct list_head *next = NULL; + bctx_t *entry = NULL; + bctx_t *del = NULL, *tmp = NULL; + + if (!table) + return 0; + + INIT_LIST_HEAD (&purge); + + LOCK (&table->lock); + { + if ((table->lru_limit) && + (table->lru_size > table->lru_limit)) { + while (table->lru_size > table->lru_limit) { + next = table->b_lru.next; + entry = list_entry (next, bctx_t, list); + + list_move_tail (next, &table->purge); + __unhash_bctx (entry); + + table->lru_size--; + ret++; + } + } + list_move_tail (&purge, &table->purge); + list_del_init (&table->purge); + } + UNLOCK (&table->lock); + + { + list_for_each_entry_safe (del, tmp, &purge, list) { + list_del_init (&del->list); + if (del->dbp) { + ret = del->dbp->close (del->dbp, 0); + if (ret != 0) { + gf_log (table->this->name, GF_LOG_ERROR, + "failed to close db on path (%s): %s", + del->directory, db_strerror (ret)); + } else { + gf_log (table->this->name, GF_LOG_WARNING, + "close db for path %s; table->lru_count = %d", + del->directory, table->lru_size); + } + } + __destroy_bctx (del); + } + } + + return ret; +} + + +/* struct bdb_ctx related */ +static inline uint32_t +bdb_key_hash (char *key, uint32_t hash_size) +{ + uint32_t hash = 0; + + hash = *key; + + if (hash) { + for (key += 1; *key != '\0'; key++) { + hash = (hash << 5) - hash + *key; + } + } + + return (hash + *key) % hash_size; +} + +static void +__hash_bctx (bctx_t *bctx) +{ + bctx_table_t *table = NULL; + char *key = NULL; + + table = bctx->table; + + MAKE_KEY_FROM_PATH (key, bctx->directory); + bctx->key_hash = bdb_key_hash (key, table->hash_size); + + list_del_init (&bctx->b_hash); + list_add (&bctx->b_hash, &table->b_hash[bctx->key_hash]); +} + +static inline bctx_t * +__bctx_passivate (bctx_t *bctx) +{ + if (bctx->dbp) { + list_move_tail (&bctx->list, &(bctx->table->b_lru)); + bctx->table->lru_size++; + } else { + list_move_tail (&bctx->list, &bctx->table->purge); + __unhash_bctx (bctx); + } + return bctx; +} + +static inline bctx_t * +__bctx_activate (bctx_t *bctx) +{ + list_move (&bctx->list, &bctx->table->active); + bctx->table->lru_size--; + + return bctx; +} + +static bctx_t * +__bdb_ctx_unref (bctx_t *bctx) +{ + assert (bctx->ref); + + --bctx->ref; + + if (!bctx->ref) + bctx = __bctx_passivate (bctx); + + return bctx; +} + + +bctx_t * +bctx_unref (bctx_t *bctx) +{ + bctx_table_t *table = NULL; + + if (!bctx && !bctx->table) + return NULL; + + table = bctx->table; + + LOCK (&table->lock); + { + bctx = __bdb_ctx_unref (bctx); + } + UNLOCK (&table->lock); + + bctx_table_prune (table); + + return bctx; +} + +/* + * NOTE: __bdb_ctx_ref() is called only after holding table->lock and bctx->lock, in that order + */ +static inline bctx_t * +__bctx_ref (bctx_t *bctx) +{ + if (!bctx->ref) + __bctx_activate (bctx); + + bctx->ref++; + + return bctx; +} + +bctx_t * +bctx_ref (bctx_t *bctx) +{ + LOCK (&(bctx->table->lock)); + { + __bctx_ref (bctx); + } + UNLOCK (&(bctx->table->lock)); + + return bctx; +} + + +#define BDB_THIS(table) (table->this) + +static inline bctx_t * +__create_bctx (bctx_table_t *table, + const char *path) +{ + bctx_t *bctx = NULL; + char *db_path = NULL; + + bctx = CALLOC (1, sizeof (*bctx)); + GF_VALIDATE_OR_GOTO ("bctx", bctx, out); + + bctx->table = table; + bctx->directory = strdup (path); + GF_VALIDATE_OR_GOTO ("bctx", bctx->directory, out); + + MAKE_REAL_PATH_TO_STORAGE_DB (db_path, BDB_THIS (table), path); + + bctx->db_path = strdup (db_path); + GF_VALIDATE_OR_GOTO ("bctx", bctx->directory, out); + + INIT_LIST_HEAD (&bctx->c_list); + INIT_LIST_HEAD (&bctx->list); + INIT_LIST_HEAD (&bctx->b_hash); + + LOCK_INIT (&bctx->lock); + + __hash_bctx (bctx); + + list_add (&bctx->list, &table->b_lru); + table->lru_size++; + +out: + return bctx; +} + +/* bctx_lookup - lookup bctx_t for the directory @directory. (see description of bctx_t in bdb.h) + * + * @table: bctx_table_t for this instance of bdb. + * @directory: directory for which bctx_t is being looked up. + */ +bctx_t * +bctx_lookup (bctx_table_t *table, + const char *directory) +{ + char *key = NULL; + uint32_t key_hash = 0; + bctx_t *trav = NULL, *bctx = NULL, *tmp = NULL; + int32_t need_break = 0; + + GF_VALIDATE_OR_GOTO ("bctx", table, out); + GF_VALIDATE_OR_GOTO ("bctx", directory, out); + + MAKE_KEY_FROM_PATH (key, directory); + key_hash = bdb_key_hash (key, table->hash_size); + + LOCK (&table->lock); + { + if (!list_empty (&table->b_hash[key_hash])) { + list_for_each_entry_safe (trav, tmp, &table->b_hash[key_hash], b_hash) { + LOCK(&trav->lock); + if (!strcmp(trav->directory, directory)) { + bctx = __bctx_ref (trav); + need_break = 1; + } + UNLOCK(&trav->lock); + if (need_break) + break; + } + } + + if (!bctx) { + bctx = __create_bctx (table, directory); + bctx = __bctx_ref (bctx); + } + } + UNLOCK (&table->lock); +out: + return bctx; +} + + +bctx_t * +bctx_parent (bctx_table_t *table, + const char *path) +{ + char *pathname = NULL, *directory = NULL; + bctx_t *bctx = NULL; + + GF_VALIDATE_OR_GOTO ("bctx", table, out); + GF_VALIDATE_OR_GOTO ("bctx", path, out); + + pathname = strdup (path); + GF_VALIDATE_OR_GOTO ("bctx", pathname, out); + directory = dirname (pathname); + + bctx = bctx_lookup (table, directory); + GF_VALIDATE_OR_GOTO ("bctx", bctx, out); + +out: + if (pathname) + free (pathname); + return bctx; +} + +inline int32_t +bdb_db_rename (bctx_table_t *table, + const char *oldpath, + const char *newpath) +{ + DB_ENV *dbenv = NULL; + int32_t ret = -1; + + GF_VALIDATE_OR_GOTO ("bctx", table, out); + GF_VALIDATE_OR_GOTO ("bctx", oldpath, out); + GF_VALIDATE_OR_GOTO ("bctx", newpath, out); + + dbenv = table->dbenv; + GF_VALIDATE_OR_GOTO ("bctx", dbenv, out); + + LOCK (&table->lock); + { + ret = dbenv->dbrename (dbenv, NULL, oldpath, NULL, newpath, 0); + + if (ret != 0) { + gf_log ("bctx", + GF_LOG_ERROR, + "failed to rename %s to %s: %s", + oldpath, newpath, db_strerror (ret)); + } else { + gf_log ("bctx", + GF_LOG_DEBUG, + "successfully renamed %s to %s: %s", + oldpath, newpath, db_strerror (ret)); + } + } + UNLOCK (&table->lock); + +out: + return ret; +} + +bctx_t * +bctx_rename (bctx_t *bctx, + const char *db_newpath) +{ + bctx_table_t *table = NULL; + int32_t ret = -1; + + table = bctx->table; + + LOCK (&table->lock); + { + __unhash_bctx (bctx); + list_del_init (&bctx->list); + if (bctx->dbp) { + ret = bctx->dbp->close (bctx->dbp, 0); + if (ret != 0) { + gf_log ("bdb-ll", + GF_LOG_ERROR, + "failed to close db for directory %s (%s)", + bctx->directory, db_strerror (ret)); + } + bctx->dbp = NULL; + } + } + UNLOCK (&table->lock); + + ret = bdb_db_rename (table, bctx->db_path, db_newpath); + + if (ret != 0) { + gf_log ("bctx", + GF_LOG_ERROR, + "bdb_db_rename failed for directory %s", + bctx->directory); + bctx = NULL; + } + + return bctx; +} |