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-rw-r--r--fs/ocfs2/dlmglue.c97
-rw-r--r--fs/ocfs2/dlmglue.h1
-rw-r--r--fs/ocfs2/heartbeat.c40
-rw-r--r--fs/ocfs2/heartbeat.h2
-rw-r--r--fs/ocfs2/ocfs2.h4
-rw-r--r--fs/ocfs2/stackglue.c131
-rw-r--r--fs/ocfs2/stackglue.h35
-rw-r--r--fs/ocfs2/super.c13
8 files changed, 221 insertions, 102 deletions
diff --git a/fs/ocfs2/dlmglue.c b/fs/ocfs2/dlmglue.c
index 459037653e5..6652a48cbe0 100644
--- a/fs/ocfs2/dlmglue.c
+++ b/fs/ocfs2/dlmglue.c
@@ -27,7 +27,6 @@
#include <linux/slab.h>
#include <linux/highmem.h>
#include <linux/mm.h>
-#include <linux/crc32.h>
#include <linux/kthread.h>
#include <linux/pagemap.h>
#include <linux/debugfs.h>
@@ -259,31 +258,6 @@ static struct ocfs2_lock_res_ops ocfs2_flock_lops = {
.flags = 0,
};
-/*
- * This is the filesystem locking protocol version.
- *
- * Whenever the filesystem does new things with locks (adds or removes a
- * lock, orders them differently, does different things underneath a lock),
- * the version must be changed. The protocol is negotiated when joining
- * the dlm domain. A node may join the domain if its major version is
- * identical to all other nodes and its minor version is greater than
- * or equal to all other nodes. When its minor version is greater than
- * the other nodes, it will run at the minor version specified by the
- * other nodes.
- *
- * If a locking change is made that will not be compatible with older
- * versions, the major number must be increased and the minor version set
- * to zero. If a change merely adds a behavior that can be disabled when
- * speaking to older versions, the minor version must be increased. If a
- * change adds a fully backwards compatible change (eg, LVB changes that
- * are just ignored by older versions), the version does not need to be
- * updated.
- */
-const struct dlm_protocol_version ocfs2_locking_protocol = {
- .pv_major = OCFS2_LOCKING_PROTOCOL_MAJOR,
- .pv_minor = OCFS2_LOCKING_PROTOCOL_MINOR,
-};
-
static inline int ocfs2_is_inode_lock(struct ocfs2_lock_res *lockres)
{
return lockres->l_type == OCFS2_LOCK_TYPE_META ||
@@ -886,7 +860,7 @@ static int ocfs2_lock_create(struct ocfs2_super *osb,
lockres_or_flags(lockres, OCFS2_LOCK_BUSY);
spin_unlock_irqrestore(&lockres->l_lock, flags);
- ret = ocfs2_dlm_lock(osb->dlm,
+ ret = ocfs2_dlm_lock(osb->cconn,
level,
&lockres->l_lksb,
dlm_flags,
@@ -1085,7 +1059,7 @@ again:
lockres->l_name, lockres->l_level, level);
/* call dlm_lock to upgrade lock now */
- ret = ocfs2_dlm_lock(osb->dlm,
+ ret = ocfs2_dlm_lock(osb->cconn,
level,
&lockres->l_lksb,
lkm_flags,
@@ -1492,7 +1466,7 @@ int ocfs2_file_lock(struct file *file, int ex, int trylock)
lockres_add_mask_waiter(lockres, &mw, OCFS2_LOCK_BUSY, 0);
spin_unlock_irqrestore(&lockres->l_lock, flags);
- ret = ocfs2_dlm_lock(osb->dlm, level, &lockres->l_lksb, lkm_flags,
+ ret = ocfs2_dlm_lock(osb->cconn, level, &lockres->l_lksb, lkm_flags,
lockres->l_name, OCFS2_LOCK_ID_MAX_LEN - 1,
lockres);
if (ret) {
@@ -2485,8 +2459,7 @@ static void ocfs2_dlm_shutdown_debug(struct ocfs2_super *osb)
int ocfs2_dlm_init(struct ocfs2_super *osb)
{
int status = 0;
- u32 dlm_key;
- struct dlm_ctxt *dlm = NULL;
+ struct ocfs2_cluster_connection *conn = NULL;
mlog_entry_void();
@@ -2508,26 +2481,21 @@ int ocfs2_dlm_init(struct ocfs2_super *osb)
goto bail;
}
- /* used by the dlm code to make message headers unique, each
- * node in this domain must agree on this. */
- dlm_key = crc32_le(0, osb->uuid_str, strlen(osb->uuid_str));
-
/* for now, uuid == domain */
- dlm = dlm_register_domain(osb->uuid_str, dlm_key,
- &osb->osb_locking_proto);
- if (IS_ERR(dlm)) {
- status = PTR_ERR(dlm);
+ status = ocfs2_cluster_connect(osb->uuid_str,
+ strlen(osb->uuid_str),
+ ocfs2_do_node_down, osb,
+ &conn);
+ if (status) {
mlog_errno(status);
goto bail;
}
- dlm_register_eviction_cb(dlm, &osb->osb_eviction_cb);
-
local:
ocfs2_super_lock_res_init(&osb->osb_super_lockres, osb);
ocfs2_rename_lock_res_init(&osb->osb_rename_lockres, osb);
- osb->dlm = dlm;
+ osb->cconn = conn;
status = 0;
bail:
@@ -2545,10 +2513,14 @@ void ocfs2_dlm_shutdown(struct ocfs2_super *osb)
{
mlog_entry_void();
- dlm_unregister_eviction_cb(&osb->osb_eviction_cb);
-
ocfs2_drop_osb_locks(osb);
+ /*
+ * Now that we have dropped all locks and ocfs2_dismount_volume()
+ * has disabled recovery, the DLM won't be talking to us. It's
+ * safe to tear things down before disconnecting the cluster.
+ */
+
if (osb->dc_task) {
kthread_stop(osb->dc_task);
osb->dc_task = NULL;
@@ -2557,8 +2529,8 @@ void ocfs2_dlm_shutdown(struct ocfs2_super *osb)
ocfs2_lock_res_free(&osb->osb_super_lockres);
ocfs2_lock_res_free(&osb->osb_rename_lockres);
- dlm_unregister_domain(osb->dlm);
- osb->dlm = NULL;
+ ocfs2_cluster_disconnect(osb->cconn);
+ osb->cconn = NULL;
ocfs2_dlm_shutdown_debug(osb);
@@ -2689,7 +2661,7 @@ static int ocfs2_drop_lock(struct ocfs2_super *osb,
mlog(0, "lock %s\n", lockres->l_name);
- ret = ocfs2_dlm_unlock(osb->dlm, &lockres->l_lksb, lkm_flags,
+ ret = ocfs2_dlm_unlock(osb->cconn, &lockres->l_lksb, lkm_flags,
lockres);
if (ret) {
ocfs2_log_dlm_error("ocfs2_dlm_unlock", ret, lockres);
@@ -2823,7 +2795,7 @@ static int ocfs2_downconvert_lock(struct ocfs2_super *osb,
if (lvb)
dlm_flags |= DLM_LKF_VALBLK;
- ret = ocfs2_dlm_lock(osb->dlm,
+ ret = ocfs2_dlm_lock(osb->cconn,
new_level,
&lockres->l_lksb,
dlm_flags,
@@ -2882,7 +2854,7 @@ static int ocfs2_cancel_convert(struct ocfs2_super *osb,
mlog_entry_void();
mlog(0, "lock %s\n", lockres->l_name);
- ret = ocfs2_dlm_unlock(osb->dlm, &lockres->l_lksb,
+ ret = ocfs2_dlm_unlock(osb->cconn, &lockres->l_lksb,
DLM_LKF_CANCEL, lockres);
if (ret) {
ocfs2_log_dlm_error("ocfs2_dlm_unlock", ret, lockres);
@@ -3193,7 +3165,34 @@ static int ocfs2_dentry_convert_worker(struct ocfs2_lock_res *lockres,
return UNBLOCK_CONTINUE_POST;
}
+/*
+ * This is the filesystem locking protocol. It provides the lock handling
+ * hooks for the underlying DLM. It has a maximum version number.
+ * The version number allows interoperability with systems running at
+ * the same major number and an equal or smaller minor number.
+ *
+ * Whenever the filesystem does new things with locks (adds or removes a
+ * lock, orders them differently, does different things underneath a lock),
+ * the version must be changed. The protocol is negotiated when joining
+ * the dlm domain. A node may join the domain if its major version is
+ * identical to all other nodes and its minor version is greater than
+ * or equal to all other nodes. When its minor version is greater than
+ * the other nodes, it will run at the minor version specified by the
+ * other nodes.
+ *
+ * If a locking change is made that will not be compatible with older
+ * versions, the major number must be increased and the minor version set
+ * to zero. If a change merely adds a behavior that can be disabled when
+ * speaking to older versions, the minor version must be increased. If a
+ * change adds a fully backwards compatible change (eg, LVB changes that
+ * are just ignored by older versions), the version does not need to be
+ * updated.
+ */
static struct ocfs2_locking_protocol lproto = {
+ .lp_max_version = {
+ .pv_major = OCFS2_LOCKING_PROTOCOL_MAJOR,
+ .pv_minor = OCFS2_LOCKING_PROTOCOL_MINOR,
+ },
.lp_lock_ast = ocfs2_locking_ast,
.lp_blocking_ast = ocfs2_blocking_ast,
.lp_unlock_ast = ocfs2_unlock_ast,
diff --git a/fs/ocfs2/dlmglue.h b/fs/ocfs2/dlmglue.h
index 32380439401..2d0a8a03c43 100644
--- a/fs/ocfs2/dlmglue.h
+++ b/fs/ocfs2/dlmglue.h
@@ -117,5 +117,4 @@ void ocfs2_put_dlm_debug(struct ocfs2_dlm_debug *dlm_debug);
void dlmglue_init_stack(void);
void dlmglue_exit_stack(void);
-extern const struct dlm_protocol_version ocfs2_locking_protocol;
#endif /* DLMGLUE_H */
diff --git a/fs/ocfs2/heartbeat.c b/fs/ocfs2/heartbeat.c
index 80de2397c16..dcac1a48728 100644
--- a/fs/ocfs2/heartbeat.c
+++ b/fs/ocfs2/heartbeat.c
@@ -30,8 +30,6 @@
#include <linux/highmem.h>
#include <linux/kmod.h>
-#include <dlm/dlmapi.h>
-
#define MLOG_MASK_PREFIX ML_SUPER
#include <cluster/masklog.h>
@@ -64,19 +62,20 @@ void ocfs2_init_node_maps(struct ocfs2_super *osb)
ocfs2_node_map_init(&osb->osb_recovering_orphan_dirs);
}
-static void ocfs2_do_node_down(int node_num,
- struct ocfs2_super *osb)
+void ocfs2_do_node_down(int node_num, void *data)
{
+ struct ocfs2_super *osb = data;
+
BUG_ON(osb->node_num == node_num);
mlog(0, "ocfs2: node down event for %d\n", node_num);
- if (!osb->dlm) {
+ if (!osb->cconn) {
/*
- * No DLM means we're not even ready to participate yet.
- * We check the slots after the DLM comes up, so we will
- * notice the node death then. We can safely ignore it
- * here.
+ * No cluster connection means we're not even ready to
+ * participate yet. We check the slots after the cluster
+ * comes up, so we will notice the node death then. We
+ * can safely ignore it here.
*/
return;
}
@@ -84,29 +83,6 @@ static void ocfs2_do_node_down(int node_num,
ocfs2_recovery_thread(osb, node_num);
}
-/* Called from the dlm when it's about to evict a node. We may also
- * get a heartbeat callback later. */
-static void ocfs2_dlm_eviction_cb(int node_num,
- void *data)
-{
- struct ocfs2_super *osb = (struct ocfs2_super *) data;
- struct super_block *sb = osb->sb;
-
- mlog(ML_NOTICE, "device (%u,%u): dlm has evicted node %d\n",
- MAJOR(sb->s_dev), MINOR(sb->s_dev), node_num);
-
- ocfs2_do_node_down(node_num, osb);
-}
-
-void ocfs2_setup_hb_callbacks(struct ocfs2_super *osb)
-{
- /* Not exactly a heartbeat callback, but leads to essentially
- * the same path so we set it up here. */
- dlm_setup_eviction_cb(&osb->osb_eviction_cb,
- ocfs2_dlm_eviction_cb,
- osb);
-}
-
void ocfs2_stop_heartbeat(struct ocfs2_super *osb)
{
int ret;
diff --git a/fs/ocfs2/heartbeat.h b/fs/ocfs2/heartbeat.h
index 98d8ffc995b..38e2450bf14 100644
--- a/fs/ocfs2/heartbeat.h
+++ b/fs/ocfs2/heartbeat.h
@@ -28,7 +28,7 @@
void ocfs2_init_node_maps(struct ocfs2_super *osb);
-void ocfs2_setup_hb_callbacks(struct ocfs2_super *osb);
+void ocfs2_do_node_down(int node_num, void *data);
void ocfs2_stop_heartbeat(struct ocfs2_super *osb);
/* node map functions - used to keep track of mounted and in-recovery
diff --git a/fs/ocfs2/ocfs2.h b/fs/ocfs2/ocfs2.h
index 6d7c6d2d0c2..664e4fe3eab 100644
--- a/fs/ocfs2/ocfs2.h
+++ b/fs/ocfs2/ocfs2.h
@@ -248,12 +248,10 @@ struct ocfs2_super
struct ocfs2_alloc_stats alloc_stats;
char dev_str[20]; /* "major,minor" of the device */
- struct dlm_ctxt *dlm;
+ struct ocfs2_cluster_connection *cconn;
struct ocfs2_lock_res osb_super_lockres;
struct ocfs2_lock_res osb_rename_lockres;
- struct dlm_eviction_cb osb_eviction_cb;
struct ocfs2_dlm_debug *osb_dlm_debug;
- struct dlm_protocol_version osb_locking_proto;
struct dentry *osb_debug_root;
diff --git a/fs/ocfs2/stackglue.c b/fs/ocfs2/stackglue.c
index eb88854cb97..f6f309a0834 100644
--- a/fs/ocfs2/stackglue.c
+++ b/fs/ocfs2/stackglue.c
@@ -18,11 +18,21 @@
* General Public License for more details.
*/
+#include <linux/slab.h>
+#include <linux/crc32.h>
+
+/* Needed for AOP_TRUNCATED_PAGE in mlog_errno() */
+#include <linux/fs.h>
+
#include "cluster/masklog.h"
#include "stackglue.h"
static struct ocfs2_locking_protocol *lproto;
+struct o2dlm_private {
+ struct dlm_eviction_cb op_eviction_cb;
+};
+
/* These should be identical */
#if (DLM_LOCK_IV != LKM_IVMODE)
# error Lock modes do not match
@@ -197,7 +207,7 @@ static void o2dlm_unlock_ast_wrapper(void *astarg, enum dlm_status status)
lproto->lp_unlock_ast(astarg, error);
}
-int ocfs2_dlm_lock(struct dlm_ctxt *dlm,
+int ocfs2_dlm_lock(struct ocfs2_cluster_connection *conn,
int mode,
union ocfs2_dlm_lksb *lksb,
u32 flags,
@@ -212,15 +222,15 @@ int ocfs2_dlm_lock(struct dlm_ctxt *dlm,
BUG_ON(lproto == NULL);
- status = dlmlock(dlm, o2dlm_mode, &lksb->lksb_o2dlm, o2dlm_flags,
- name, namelen,
+ status = dlmlock(conn->cc_lockspace, o2dlm_mode, &lksb->lksb_o2dlm,
+ o2dlm_flags, name, namelen,
o2dlm_lock_ast_wrapper, astarg,
o2dlm_blocking_ast_wrapper);
ret = dlm_status_to_errno(status);
return ret;
}
-int ocfs2_dlm_unlock(struct dlm_ctxt *dlm,
+int ocfs2_dlm_unlock(struct ocfs2_cluster_connection *conn,
union ocfs2_dlm_lksb *lksb,
u32 flags,
void *astarg)
@@ -231,8 +241,8 @@ int ocfs2_dlm_unlock(struct dlm_ctxt *dlm,
BUG_ON(lproto == NULL);
- status = dlmunlock(dlm, &lksb->lksb_o2dlm, o2dlm_flags,
- o2dlm_unlock_ast_wrapper, astarg);
+ status = dlmunlock(conn->cc_lockspace, &lksb->lksb_o2dlm,
+ o2dlm_flags, o2dlm_unlock_ast_wrapper, astarg);
ret = dlm_status_to_errno(status);
return ret;
}
@@ -252,6 +262,115 @@ void *ocfs2_dlm_lvb(union ocfs2_dlm_lksb *lksb)
return (void *)(lksb->lksb_o2dlm.lvb);
}
+/*
+ * Called from the dlm when it's about to evict a node. This is how the
+ * classic stack signals node death.
+ */
+static void o2dlm_eviction_cb(int node_num, void *data)
+{
+ struct ocfs2_cluster_connection *conn = data;
+
+ mlog(ML_NOTICE, "o2dlm has evicted node %d from group %.*s\n",
+ node_num, conn->cc_namelen, conn->cc_name);
+
+ conn->cc_recovery_handler(node_num, conn->cc_recovery_data);
+}
+
+int ocfs2_cluster_connect(const char *group,
+ int grouplen,
+ void (*recovery_handler)(int node_num,
+ void *recovery_data),
+ void *recovery_data,
+ struct ocfs2_cluster_connection **conn)
+{
+ int rc = 0;
+ struct ocfs2_cluster_connection *new_conn;
+ u32 dlm_key;
+ struct dlm_ctxt *dlm;
+ struct o2dlm_private *priv;
+ struct dlm_protocol_version dlm_version;
+
+ BUG_ON(group == NULL);
+ BUG_ON(conn == NULL);
+ BUG_ON(recovery_handler == NULL);
+
+ if (grouplen > GROUP_NAME_MAX) {
+ rc = -EINVAL;
+ goto out;
+ }
+
+ new_conn = kzalloc(sizeof(struct ocfs2_cluster_connection),
+ GFP_KERNEL);
+ if (!new_conn) {
+ rc = -ENOMEM;
+ goto out;
+ }
+
+ memcpy(new_conn->cc_name, group, grouplen);
+ new_conn->cc_namelen = grouplen;
+ new_conn->cc_recovery_handler = recovery_handler;
+ new_conn->cc_recovery_data = recovery_data;
+
+ /* Start the new connection at our maximum compatibility level */
+ new_conn->cc_version = lproto->lp_max_version;
+
+ priv = kzalloc(sizeof(struct o2dlm_private), GFP_KERNEL);
+ if (!priv) {
+ rc = -ENOMEM;
+ goto out_free;
+ }
+
+ /* This just fills the structure in. It is safe to use new_conn. */
+ dlm_setup_eviction_cb(&priv->op_eviction_cb, o2dlm_eviction_cb,
+ new_conn);
+
+ new_conn->cc_private = priv;
+
+ /* used by the dlm code to make message headers unique, each
+ * node in this domain must agree on this. */
+ dlm_key = crc32_le(0, group, grouplen);
+ dlm_version.pv_major = new_conn->cc_version.pv_major;
+ dlm_version.pv_minor = new_conn->cc_version.pv_minor;
+
+ dlm = dlm_register_domain(group, dlm_key, &dlm_version);
+ if (IS_ERR(dlm)) {
+ rc = PTR_ERR(dlm);
+ mlog_errno(rc);
+ goto out_free;
+ }
+
+ new_conn->cc_version.pv_major = dlm_version.pv_major;
+ new_conn->cc_version.pv_minor = dlm_version.pv_minor;
+ new_conn->cc_lockspace = dlm;
+
+ dlm_register_eviction_cb(dlm, &priv->op_eviction_cb);
+
+ *conn = new_conn;
+
+out_free:
+ if (rc) {
+ kfree(new_conn->cc_private);
+ kfree(new_conn);
+ }
+
+out:
+ return rc;
+}
+
+int ocfs2_cluster_disconnect(struct ocfs2_cluster_connection *conn)
+{
+ struct dlm_ctxt *dlm = conn->cc_lockspace;
+ struct o2dlm_private *priv = conn->cc_private;
+
+ dlm_unregister_eviction_cb(&priv->op_eviction_cb);
+ dlm_unregister_domain(dlm);
+
+ kfree(priv);
+ kfree(conn);
+
+ return 0;
+}
+
void o2cb_get_stack(struct ocfs2_locking_protocol *proto)
{
BUG_ON(proto == NULL);
diff --git a/fs/ocfs2/stackglue.h b/fs/ocfs2/stackglue.h
index 3c91e241892..3900b5c3933 100644
--- a/fs/ocfs2/stackglue.h
+++ b/fs/ocfs2/stackglue.h
@@ -32,9 +32,22 @@
*/
#define DLM_LKF_LOCAL 0x00100000
+/*
+ * This shadows DLM_LOCKSPACE_LEN in fs/dlm/dlm_internal.h. That probably
+ * wants to be in a public header.
+ */
+#define GROUP_NAME_MAX 64
+
+
#include "dlm/dlmapi.h"
+struct ocfs2_protocol_version {
+ u8 pv_major;
+ u8 pv_minor;
+};
+
struct ocfs2_locking_protocol {
+ struct ocfs2_protocol_version lp_max_version;
void (*lp_lock_ast)(void *astarg);
void (*lp_blocking_ast)(void *astarg, int level);
void (*lp_unlock_ast)(void *astarg, int error);
@@ -44,14 +57,32 @@ union ocfs2_dlm_lksb {
struct dlm_lockstatus lksb_o2dlm;
};
-int ocfs2_dlm_lock(struct dlm_ctxt *dlm,
+struct ocfs2_cluster_connection {
+ char cc_name[GROUP_NAME_MAX];
+ int cc_namelen;
+ struct ocfs2_protocol_version cc_version;
+ void (*cc_recovery_handler)(int node_num, void *recovery_data);
+ void *cc_recovery_data;
+ void *cc_lockspace;
+ void *cc_private;
+};
+
+int ocfs2_cluster_connect(const char *group,
+ int grouplen,
+ void (*recovery_handler)(int node_num,
+ void *recovery_data),
+ void *recovery_data,
+ struct ocfs2_cluster_connection **conn);
+int ocfs2_cluster_disconnect(struct ocfs2_cluster_connection *conn);
+
+int ocfs2_dlm_lock(struct ocfs2_cluster_connection *conn,
int mode,
union ocfs2_dlm_lksb *lksb,
u32 flags,
void *name,
unsigned int namelen,
void *astarg);
-int ocfs2_dlm_unlock(struct dlm_ctxt *dlm,
+int ocfs2_dlm_unlock(struct ocfs2_cluster_connection *conn,
union ocfs2_dlm_lksb *lksb,
u32 flags,
void *astarg);
diff --git a/fs/ocfs2/super.c b/fs/ocfs2/super.c
index c8675464e29..0ee49757467 100644
--- a/fs/ocfs2/super.c
+++ b/fs/ocfs2/super.c
@@ -1251,9 +1251,9 @@ static void ocfs2_dismount_volume(struct super_block *sb, int mnt_err)
ocfs2_sync_blockdev(sb);
- /* No dlm means we've failed during mount, so skip all the
- * steps which depended on that to complete. */
- if (osb->dlm) {
+ /* No cluster connection means we've failed during mount, so skip
+ * all the steps which depended on that to complete. */
+ if (osb->cconn) {
tmp = ocfs2_super_lock(osb, 1);
if (tmp < 0) {
mlog_errno(tmp);
@@ -1264,12 +1264,12 @@ static void ocfs2_dismount_volume(struct super_block *sb, int mnt_err)
if (osb->slot_num != OCFS2_INVALID_SLOT)
ocfs2_put_slot(osb);
- if (osb->dlm)
+ if (osb->cconn)
ocfs2_super_unlock(osb, 1);
ocfs2_release_system_inodes(osb);
- if (osb->dlm)
+ if (osb->cconn)
ocfs2_dlm_shutdown(osb);
debugfs_remove(osb->osb_debug_root);
@@ -1341,7 +1341,6 @@ static int ocfs2_initialize_super(struct super_block *sb,
sb->s_fs_info = osb;
sb->s_op = &ocfs2_sops;
sb->s_export_op = &ocfs2_export_ops;
- osb->osb_locking_proto = ocfs2_locking_protocol;
sb->s_time_gran = 1;
sb->s_flags |= MS_NOATIME;
/* this is needed to support O_LARGEFILE */
@@ -1391,8 +1390,6 @@ static int ocfs2_initialize_super(struct super_block *sb,
osb->local_alloc_state = OCFS2_LA_UNUSED;
osb->local_alloc_bh = NULL;
- ocfs2_setup_hb_callbacks(osb);
-
init_waitqueue_head(&osb->osb_mount_event);
osb->vol_label = kmalloc(OCFS2_MAX_VOL_LABEL_LEN, GFP_KERNEL);