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-rw-r--r--xlators/mgmt/glusterd/src/glusterd-locks.c177
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;
+}