ocfs: no need to check return value of debugfs_create functions

When calling debugfs functions, there is no need to ever check the
return value.  The function can work or not, but the code logic should
never do something different based on this.

Also, because there is no need to save the file dentry, remove all of
the variables that were being saved, and just recursively delete the
whole directory when shutting down, saving a lot of logic and local
variables.

[gregkh@linuxfoundation.org: v2]
  Link: http://lkml.kernel.org/r/20190613055455.GE19717@kroah.com
Link: http://lkml.kernel.org/r/20190612152912.GA19151@kroah.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Jia Guo <guojia12@huawei.com>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/ocfs2/blockcheck.c

@@ -242,57 +242,29 @@ static struct dentry *blockcheck_debugfs_create(const char *name,
 static void ocfs2_blockcheck_debug_remove(struct ocfs2_blockcheck_stats *stats)
 {
 	if (stats) {
-		debugfs_remove(stats->b_debug_check);
-		stats->b_debug_check = NULL;
-		debugfs_remove(stats->b_debug_failure);
-		stats->b_debug_failure = NULL;
-		debugfs_remove(stats->b_debug_recover);
-		stats->b_debug_recover = NULL;
-		debugfs_remove(stats->b_debug_dir);
+		debugfs_remove_recursive(stats->b_debug_dir);
 		stats->b_debug_dir = NULL;
 	}
 }
 
-static int ocfs2_blockcheck_debug_install(struct ocfs2_blockcheck_stats *stats,
-					  struct dentry *parent)
+static void ocfs2_blockcheck_debug_install(struct ocfs2_blockcheck_stats *stats,
+					   struct dentry *parent)
 {
-	int rc = -EINVAL;
-
-	if (!stats)
-		goto out;
-
 	stats->b_debug_dir = debugfs_create_dir("blockcheck", parent);
-	if (!stats->b_debug_dir)
-		goto out;
 
-	stats->b_debug_check =
-		blockcheck_debugfs_create("blocks_checked",
-					  stats->b_debug_dir,
-					  &stats->b_check_count);
+	blockcheck_debugfs_create("blocks_checked", stats->b_debug_dir,
+				  &stats->b_check_count);
 
-	stats->b_debug_failure =
-		blockcheck_debugfs_create("checksums_failed",
-					  stats->b_debug_dir,
-					  &stats->b_failure_count);
+	blockcheck_debugfs_create("checksums_failed", stats->b_debug_dir,
+				  &stats->b_failure_count);
 
-	stats->b_debug_recover =
-		blockcheck_debugfs_create("ecc_recoveries",
-					  stats->b_debug_dir,
-					  &stats->b_recover_count);
-	if (stats->b_debug_check && stats->b_debug_failure &&
-	    stats->b_debug_recover)
-		rc = 0;
-
-out:
-	if (rc)
-		ocfs2_blockcheck_debug_remove(stats);
-	return rc;
+	blockcheck_debugfs_create("ecc_recoveries", stats->b_debug_dir,
+				  &stats->b_recover_count);
 }
 #else
-static inline int ocfs2_blockcheck_debug_install(struct ocfs2_blockcheck_stats *stats,
-						 struct dentry *parent)
+static inline void ocfs2_blockcheck_debug_install(struct ocfs2_blockcheck_stats *stats,
+						  struct dentry *parent)
 {
-	return 0;
 }
 
 static inline void ocfs2_blockcheck_debug_remove(struct ocfs2_blockcheck_stats *stats)
@@ -301,10 +273,10 @@ static inline void ocfs2_blockcheck_debug_remove(struct ocfs2_blockcheck_stats *
 #endif  /* CONFIG_DEBUG_FS */
 
 /* Always-called wrappers for starting and stopping the debugfs files */
-int ocfs2_blockcheck_stats_debugfs_install(struct ocfs2_blockcheck_stats *stats,
-					   struct dentry *parent)
+void ocfs2_blockcheck_stats_debugfs_install(struct ocfs2_blockcheck_stats *stats,
+					    struct dentry *parent)
 {
-	return ocfs2_blockcheck_debug_install(stats, parent);
+	ocfs2_blockcheck_debug_install(stats, parent);
 }
 
 void ocfs2_blockcheck_stats_debugfs_remove(struct ocfs2_blockcheck_stats *stats)

fs/ocfs2/blockcheck.h

@@ -25,9 +25,6 @@ struct ocfs2_blockcheck_stats {
 	 * ocfs2_blockcheck_stats_debugfs_install()
 	 */
 	struct dentry *b_debug_dir;	/* Parent of the debugfs  files */
-	struct dentry *b_debug_check;	/* Exposes b_check_count */
-	struct dentry *b_debug_failure;	/* Exposes b_failure_count */
-	struct dentry *b_debug_recover;	/* Exposes b_recover_count */
 };
 
 
@@ -56,8 +53,8 @@ int ocfs2_block_check_validate_bhs(struct buffer_head **bhs, int nr,
 				   struct ocfs2_blockcheck_stats *stats);
 
 /* Debug Initialization */
-int ocfs2_blockcheck_stats_debugfs_install(struct ocfs2_blockcheck_stats *stats,
-					   struct dentry *parent);
+void ocfs2_blockcheck_stats_debugfs_install(struct ocfs2_blockcheck_stats *stats,
+					    struct dentry *parent);
 void ocfs2_blockcheck_stats_debugfs_remove(struct ocfs2_blockcheck_stats *stats);
 
 /*

fs/ocfs2/cluster/heartbeat.c

@@ -92,10 +92,6 @@ static struct o2hb_debug_buf *o2hb_db_failedregions;
 #define O2HB_DEBUG_REGION_PINNED	"pinned"
 
 static struct dentry *o2hb_debug_dir;
-static struct dentry *o2hb_debug_livenodes;
-static struct dentry *o2hb_debug_liveregions;
-static struct dentry *o2hb_debug_quorumregions;
-static struct dentry *o2hb_debug_failedregions;
 
 static LIST_HEAD(o2hb_all_regions);
 
@@ -1391,11 +1387,7 @@ static const struct file_operations o2hb_debug_fops = {
 
 void o2hb_exit(void)
 {
-	debugfs_remove(o2hb_debug_failedregions);
-	debugfs_remove(o2hb_debug_quorumregions);
-	debugfs_remove(o2hb_debug_liveregions);
-	debugfs_remove(o2hb_debug_livenodes);
-	debugfs_remove(o2hb_debug_dir);
+	debugfs_remove_recursive(o2hb_debug_dir);
 	kfree(o2hb_db_livenodes);
 	kfree(o2hb_db_liveregions);
 	kfree(o2hb_db_quorumregions);
@@ -1419,79 +1411,37 @@ static struct dentry *o2hb_debug_create(const char *name, struct dentry *dir,
 				   &o2hb_debug_fops);
 }
 
-static int o2hb_debug_init(void)
+static void o2hb_debug_init(void)
 {
-	int ret = -ENOMEM;
-
 	o2hb_debug_dir = debugfs_create_dir(O2HB_DEBUG_DIR, NULL);
-	if (!o2hb_debug_dir) {
-		mlog_errno(ret);
-		goto bail;
-	}
 
-	o2hb_debug_livenodes = o2hb_debug_create(O2HB_DEBUG_LIVENODES,
-						 o2hb_debug_dir,
-						 &o2hb_db_livenodes,
-						 sizeof(*o2hb_db_livenodes),
-						 O2HB_DB_TYPE_LIVENODES,
-						 sizeof(o2hb_live_node_bitmap),
-						 O2NM_MAX_NODES,
-						 o2hb_live_node_bitmap);
-	if (!o2hb_debug_livenodes) {
-		mlog_errno(ret);
-		goto bail;
-	}
+	o2hb_debug_create(O2HB_DEBUG_LIVENODES, o2hb_debug_dir,
+			  &o2hb_db_livenodes, sizeof(*o2hb_db_livenodes),
+			  O2HB_DB_TYPE_LIVENODES, sizeof(o2hb_live_node_bitmap),
+			  O2NM_MAX_NODES, o2hb_live_node_bitmap);
 
-	o2hb_debug_liveregions = o2hb_debug_create(O2HB_DEBUG_LIVEREGIONS,
-						   o2hb_debug_dir,
-						   &o2hb_db_liveregions,
-						   sizeof(*o2hb_db_liveregions),
-						   O2HB_DB_TYPE_LIVEREGIONS,
-						   sizeof(o2hb_live_region_bitmap),
-						   O2NM_MAX_REGIONS,
-						   o2hb_live_region_bitmap);
-	if (!o2hb_debug_liveregions) {
-		mlog_errno(ret);
-		goto bail;
-	}
+	o2hb_debug_create(O2HB_DEBUG_LIVEREGIONS, o2hb_debug_dir,
+			  &o2hb_db_liveregions, sizeof(*o2hb_db_liveregions),
+			  O2HB_DB_TYPE_LIVEREGIONS,
+			  sizeof(o2hb_live_region_bitmap), O2NM_MAX_REGIONS,
+			  o2hb_live_region_bitmap);
 
-	o2hb_debug_quorumregions =
-			o2hb_debug_create(O2HB_DEBUG_QUORUMREGIONS,
-					  o2hb_debug_dir,
-					  &o2hb_db_quorumregions,
-					  sizeof(*o2hb_db_quorumregions),
-					  O2HB_DB_TYPE_QUORUMREGIONS,
-					  sizeof(o2hb_quorum_region_bitmap),
-					  O2NM_MAX_REGIONS,
-					  o2hb_quorum_region_bitmap);
-	if (!o2hb_debug_quorumregions) {
-		mlog_errno(ret);
-		goto bail;
-	}
-
-	o2hb_debug_failedregions =
-			o2hb_debug_create(O2HB_DEBUG_FAILEDREGIONS,
-					  o2hb_debug_dir,
-					  &o2hb_db_failedregions,
-					  sizeof(*o2hb_db_failedregions),
-					  O2HB_DB_TYPE_FAILEDREGIONS,
-					  sizeof(o2hb_failed_region_bitmap),
-					  O2NM_MAX_REGIONS,
-					  o2hb_failed_region_bitmap);
-	if (!o2hb_debug_failedregions) {
-		mlog_errno(ret);
-		goto bail;
-	}
+	o2hb_debug_create(O2HB_DEBUG_QUORUMREGIONS, o2hb_debug_dir,
+			  &o2hb_db_quorumregions,
+			  sizeof(*o2hb_db_quorumregions),
+			  O2HB_DB_TYPE_QUORUMREGIONS,
+			  sizeof(o2hb_quorum_region_bitmap), O2NM_MAX_REGIONS,
+			  o2hb_quorum_region_bitmap);
 
-	ret = 0;
-bail:
-	if (ret)
-		o2hb_exit();
-
-	return ret;
+	o2hb_debug_create(O2HB_DEBUG_FAILEDREGIONS, o2hb_debug_dir,
+			  &o2hb_db_failedregions,
+			  sizeof(*o2hb_db_failedregions),
+			  O2HB_DB_TYPE_FAILEDREGIONS,
+			  sizeof(o2hb_failed_region_bitmap), O2NM_MAX_REGIONS,
+			  o2hb_failed_region_bitmap);
 }
 
-int o2hb_init(void)
+void o2hb_init(void)
 {
 	int i;
 
@@ -1511,7 +1461,7 @@ int o2hb_init(void)
 
 	o2hb_dependent_users = 0;
 
-	return o2hb_debug_init();
+	o2hb_debug_init();
 }
 
 /* if we're already in a callback then we're already serialized by the sem */

fs/ocfs2/cluster/heartbeat.h

@@ -63,7 +63,7 @@ void o2hb_unregister_callback(const char *region_uuid,
 void o2hb_fill_node_map(unsigned long *map,
 			unsigned bytes);
 void o2hb_exit(void);
-int o2hb_init(void);
+void o2hb_init(void);
 int o2hb_check_node_heartbeating_no_sem(u8 node_num);
 int o2hb_check_node_heartbeating_from_callback(u8 node_num);
 void o2hb_stop_all_regions(void);

fs/ocfs2/cluster/netdebug.c

@@ -38,10 +38,6 @@
 #define SHOW_SOCK_STATS		1
 
 static struct dentry *o2net_dentry;
-static struct dentry *sc_dentry;
-static struct dentry *nst_dentry;
-static struct dentry *stats_dentry;
-static struct dentry *nodes_dentry;
 
 static DEFINE_SPINLOCK(o2net_debug_lock);
 
@@ -490,36 +486,23 @@ static const struct file_operations nodes_fops = {
 
 void o2net_debugfs_exit(void)
 {
-	debugfs_remove(nodes_dentry);
-	debugfs_remove(stats_dentry);
-	debugfs_remove(sc_dentry);
-	debugfs_remove(nst_dentry);
-	debugfs_remove(o2net_dentry);
+	debugfs_remove_recursive(o2net_dentry);
 }
 
-int o2net_debugfs_init(void)
+void o2net_debugfs_init(void)
 {
 	umode_t mode = S_IFREG|S_IRUSR;
 
 	o2net_dentry = debugfs_create_dir(O2NET_DEBUG_DIR, NULL);
-	if (o2net_dentry)
-		nst_dentry = debugfs_create_file(NST_DEBUG_NAME, mode,
-					o2net_dentry, NULL, &nst_seq_fops);
-	if (nst_dentry)
-		sc_dentry = debugfs_create_file(SC_DEBUG_NAME, mode,
-					o2net_dentry, NULL, &sc_seq_fops);
-	if (sc_dentry)
-		stats_dentry = debugfs_create_file(STATS_DEBUG_NAME, mode,
-					o2net_dentry, NULL, &stats_seq_fops);
-	if (stats_dentry)
-		nodes_dentry = debugfs_create_file(NODES_DEBUG_NAME, mode,
-					o2net_dentry, NULL, &nodes_fops);
-	if (nodes_dentry)
-		return 0;
-
-	o2net_debugfs_exit();
-	mlog_errno(-ENOMEM);
-	return -ENOMEM;
+
+	debugfs_create_file(NST_DEBUG_NAME, mode, o2net_dentry, NULL,
+			    &nst_seq_fops);
+	debugfs_create_file(SC_DEBUG_NAME, mode, o2net_dentry, NULL,
+			    &sc_seq_fops);
+	debugfs_create_file(STATS_DEBUG_NAME, mode, o2net_dentry, NULL,
+			    &stats_seq_fops);
+	debugfs_create_file(NODES_DEBUG_NAME, mode, o2net_dentry, NULL,
+			    &nodes_fops);
 }
 
 #endif	/* CONFIG_DEBUG_FS */

fs/ocfs2/cluster/nodemanager.c

@@ -828,9 +828,7 @@ static int __init init_o2nm(void)
 {
 	int ret = -1;
 
-	ret = o2hb_init();
-	if (ret)
-		goto out;
+	o2hb_init();
 
 	ret = o2net_init();
 	if (ret)

fs/ocfs2/cluster/tcp.c

@@ -2129,8 +2129,7 @@ int o2net_init(void)
 
 	o2quo_init();
 
-	if (o2net_debugfs_init())
-		goto out;
+	o2net_debugfs_init();
 
 	o2net_hand = kzalloc(sizeof(struct o2net_handshake), GFP_KERNEL);
 	o2net_keep_req = kzalloc(sizeof(struct o2net_msg), GFP_KERNEL);

fs/ocfs2/cluster/tcp.h

@@ -109,16 +109,15 @@ struct o2net_send_tracking;
 struct o2net_sock_container;
 
 #ifdef CONFIG_DEBUG_FS
-int o2net_debugfs_init(void);
+void o2net_debugfs_init(void);
 void o2net_debugfs_exit(void);
 void o2net_debug_add_nst(struct o2net_send_tracking *nst);
 void o2net_debug_del_nst(struct o2net_send_tracking *nst);
 void o2net_debug_add_sc(struct o2net_sock_container *sc);
 void o2net_debug_del_sc(struct o2net_sock_container *sc);
 #else
-static inline int o2net_debugfs_init(void)
+static inline void o2net_debugfs_init(void)
 {
-	return 0;
 }
 static inline void o2net_debugfs_exit(void)
 {