diff options
Diffstat (limited to 'xlators/mgmt/glusterd/src/glusterd-locks.c')
-rw-r--r-- | xlators/mgmt/glusterd/src/glusterd-locks.c | 177 |
1 files changed, 177 insertions, 0 deletions
diff --git a/xlators/mgmt/glusterd/src/glusterd-locks.c b/xlators/mgmt/glusterd/src/glusterd-locks.c new file mode 100644 index 00000000000..68c6d74264b --- /dev/null +++ b/xlators/mgmt/glusterd/src/glusterd-locks.c @@ -0,0 +1,177 @@ +/* + Copyright (c) 2013-2014 Red Hat, Inc. <http://www.redhat.com> + This file is part of GlusterFS. + + This file is licensed to you under your choice of the GNU Lesser + General Public License, version 3 or any later version (LGPLv3 or + later), or the GNU General Public License, version 2 (GPLv2), in all + cases as published by the Free Software Foundation. +*/ +#ifndef _CONFIG_H +#define _CONFIG_H +#include "config.h" +#endif + +#include "common-utils.h" +#include "cli1-xdr.h" +#include "xdr-generic.h" +#include "glusterd.h" +#include "glusterd-op-sm.h" +#include "glusterd-store.h" +#include "glusterd-utils.h" +#include "glusterd-volgen.h" +#include "glusterd-locks.h" +#include "run.h" +#include "syscall.h" + +#include <signal.h> + +static dict_t *vol_lock; + +/* Initialize the global vol-lock list(dict) when + * glusterd is spawned */ +int32_t +glusterd_vol_lock_init () +{ + int32_t ret = -1; + + vol_lock = dict_new (); + if (!vol_lock) + goto out; + + ret = 0; +out: + return ret; +} + +/* Destroy the global vol-lock list(dict) when + * glusterd cleanup is performed */ +void +glusterd_vol_lock_fini () +{ + if (vol_lock) + dict_unref (vol_lock); +} + +int32_t +glusterd_get_vol_lock_owner (char *volname, uuid_t *uuid) +{ + int32_t ret = -1; + vol_lock_obj *lock_obj = NULL; + uuid_t no_owner = {0,}; + + if (!volname || !uuid) { + gf_log ("", GF_LOG_ERROR, "volname or uuid is null."); + ret = -1; + goto out; + } + + ret = dict_get_bin (vol_lock, volname, (void **) &lock_obj); + if (!ret) + uuid_copy (*uuid, lock_obj->lock_owner); + else + uuid_copy (*uuid, no_owner); + + ret = 0; +out: + gf_log ("", GF_LOG_DEBUG, "Returning %d", ret); + return ret; +} + +int32_t +glusterd_volume_lock (char *volname, uuid_t uuid) +{ + int32_t ret = -1; + vol_lock_obj *lock_obj = NULL; + uuid_t owner = {0}; + + if (!volname) { + gf_log ("", GF_LOG_ERROR, "volname is null."); + ret = -1; + goto out; + } + + ret = glusterd_get_vol_lock_owner (volname, &owner); + if (ret) { + gf_log ("", GF_LOG_DEBUG, "Unable to get volume lock owner"); + goto out; + } + + /* If the lock has already been held for the given volume + * we fail */ + if (!uuid_is_null (owner)) { + gf_log ("", GF_LOG_ERROR, "Unable to acquire lock. " + "Lock for %s held by %s", volname, + uuid_utoa (owner)); + ret = -1; + goto out; + } + + lock_obj = GF_CALLOC (1, sizeof(vol_lock_obj), + gf_common_mt_vol_lock_obj_t); + if (!lock_obj) { + ret = -1; + goto out; + } + + uuid_copy (lock_obj->lock_owner, uuid); + + ret = dict_set_bin (vol_lock, volname, lock_obj, sizeof(vol_lock_obj)); + if (ret) { + gf_log ("", GF_LOG_ERROR, "Unable to set lock owner " + "in volume lock"); + if (lock_obj) + GF_FREE (lock_obj); + goto out; + } + + gf_log ("", GF_LOG_DEBUG, "Lock for %s successfully held by %s", + volname, uuid_utoa (uuid)); + + ret = 0; +out: + gf_log ("", GF_LOG_DEBUG, "Returning %d", ret); + return ret; +} + +int32_t +glusterd_volume_unlock (char *volname, uuid_t uuid) +{ + int32_t ret = -1; + uuid_t owner = {0}; + + if (!volname) { + gf_log ("", GF_LOG_ERROR, "volname is null."); + ret = -1; + goto out; + } + + ret = glusterd_get_vol_lock_owner (volname, &owner); + if (ret) + goto out; + + if (uuid_is_null (owner)) { + gf_log ("", GF_LOG_ERROR, "Lock for %s not held", volname); + ret = -1; + goto out; + } + + ret = uuid_compare (uuid, owner); + if (ret) { + gf_log (THIS->name, GF_LOG_ERROR, "Lock owner mismatch. " + "Lock for %s held by %s", + volname, uuid_utoa (owner)); + goto out; + } + + /* Removing the volume lock from the global list */ + dict_del (vol_lock, volname); + + gf_log ("", GF_LOG_DEBUG, "Lock for %s successfully released", + volname); + + ret = 0; +out: + gf_log ("", GF_LOG_DEBUG, "Returning %d", ret); + return ret; +} |