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>

3 files changed, 11 insertions, 53 deletions

diff --git a/fs/ocfs2/dlm/dlmdebug.c b/fs/ocfs2/dlm/dlmdebug.c
index c8af5bc9e980..a4b58ba99927 100644
--- a/fs/ocfs2/dlm/dlmdebug.c
+++ b/fs/ocfs2/dlm/dlmdebug.c
@@ -851,7 +851,7 @@ static const struct file_operations debug_state_fops = {
 /* end  - debug state funcs */
 
 /* files in subroot */
-int dlm_debug_init(struct dlm_ctxt *dlm)
+void dlm_debug_init(struct dlm_ctxt *dlm)
 {
 	struct dlm_debug_ctxt *dc = dlm->dlm_debug_ctxt;
 
@@ -860,10 +860,6 @@ int dlm_debug_init(struct dlm_ctxt *dlm)
 						     S_IFREG|S_IRUSR,
 						     dlm->dlm_debugfs_subroot,
 						     dlm, &debug_state_fops);
-	if (!dc->debug_state_dentry) {
-		mlog_errno(-ENOMEM);
-		goto bail;
-	}
 
 	/* for dumping lockres */
 	dc->debug_lockres_dentry =
@@ -871,20 +867,12 @@ int dlm_debug_init(struct dlm_ctxt *dlm)
 					    S_IFREG|S_IRUSR,
 					    dlm->dlm_debugfs_subroot,
 					    dlm, &debug_lockres_fops);
-	if (!dc->debug_lockres_dentry) {
-		mlog_errno(-ENOMEM);
-		goto bail;
-	}
 
 	/* for dumping mles */
 	dc->debug_mle_dentry = debugfs_create_file(DLM_DEBUGFS_MLE_STATE,
 						   S_IFREG|S_IRUSR,
 						   dlm->dlm_debugfs_subroot,
 						   dlm, &debug_mle_fops);
-	if (!dc->debug_mle_dentry) {
-		mlog_errno(-ENOMEM);
-		goto bail;
-	}
 
 	/* for dumping lockres on the purge list */
 	dc->debug_purgelist_dentry =
@@ -892,15 +880,6 @@ int dlm_debug_init(struct dlm_ctxt *dlm)
 					    S_IFREG|S_IRUSR,
 					    dlm->dlm_debugfs_subroot,
 					    dlm, &debug_purgelist_fops);
-	if (!dc->debug_purgelist_dentry) {
-		mlog_errno(-ENOMEM);
-		goto bail;
-	}
-
-	return 0;
-
-bail:
-	return -ENOMEM;
 }
 
 void dlm_debug_shutdown(struct dlm_ctxt *dlm)
@@ -920,24 +899,16 @@ void dlm_debug_shutdown(struct dlm_ctxt *dlm)
 /* subroot - domain dir */
 int dlm_create_debugfs_subroot(struct dlm_ctxt *dlm)
 {
-	dlm->dlm_debugfs_subroot = debugfs_create_dir(dlm->name,
-						      dlm_debugfs_root);
-	if (!dlm->dlm_debugfs_subroot) {
-		mlog_errno(-ENOMEM);
-		goto bail;
-	}
-
 	dlm->dlm_debug_ctxt = kzalloc(sizeof(struct dlm_debug_ctxt),
 				      GFP_KERNEL);
 	if (!dlm->dlm_debug_ctxt) {
 		mlog_errno(-ENOMEM);
-		goto bail;
+		return -ENOMEM;
 	}
 
+	dlm->dlm_debugfs_subroot = debugfs_create_dir(dlm->name,
+						      dlm_debugfs_root);
 	return 0;
-bail:
-	dlm_destroy_debugfs_subroot(dlm);
-	return -ENOMEM;
 }
 
 void dlm_destroy_debugfs_subroot(struct dlm_ctxt *dlm)
@@ -946,14 +917,9 @@ void dlm_destroy_debugfs_subroot(struct dlm_ctxt *dlm)
 }
 
 /* debugfs root */
-int dlm_create_debugfs_root(void)
+void dlm_create_debugfs_root(void)
 {
 	dlm_debugfs_root = debugfs_create_dir(DLM_DEBUGFS_DIR, NULL);
-	if (!dlm_debugfs_root) {
-		mlog_errno(-ENOMEM);
-		return -ENOMEM;
-	}
-	return 0;
 }
 
 void dlm_destroy_debugfs_root(void)
diff --git a/fs/ocfs2/dlm/dlmdebug.h b/fs/ocfs2/dlm/dlmdebug.h
index 74d019694c7e..7d0c7c9013ce 100644
--- a/fs/ocfs2/dlm/dlmdebug.h
+++ b/fs/ocfs2/dlm/dlmdebug.h
@@ -28,20 +28,19 @@ struct debug_lockres {
 	struct dlm_lock_resource *dl_res;
 };
 
-int dlm_debug_init(struct dlm_ctxt *dlm);
+void dlm_debug_init(struct dlm_ctxt *dlm);
 void dlm_debug_shutdown(struct dlm_ctxt *dlm);
 
 int dlm_create_debugfs_subroot(struct dlm_ctxt *dlm);
 void dlm_destroy_debugfs_subroot(struct dlm_ctxt *dlm);
 
-int dlm_create_debugfs_root(void);
+void dlm_create_debugfs_root(void);
 void dlm_destroy_debugfs_root(void);
 
 #else
 
-static inline int dlm_debug_init(struct dlm_ctxt *dlm)
+static inline void dlm_debug_init(struct dlm_ctxt *dlm)
 {
-	return 0;
 }
 static inline void dlm_debug_shutdown(struct dlm_ctxt *dlm)
 {
@@ -53,9 +52,8 @@ static inline int dlm_create_debugfs_subroot(struct dlm_ctxt *dlm)
 static inline void dlm_destroy_debugfs_subroot(struct dlm_ctxt *dlm)
 {
 }
-static inline int dlm_create_debugfs_root(void)
+static inline void dlm_create_debugfs_root(void)
 {
-	return 0;
 }
 static inline void dlm_destroy_debugfs_root(void)
 {
diff --git a/fs/ocfs2/dlm/dlmdomain.c b/fs/ocfs2/dlm/dlmdomain.c
index 9021e72e1f98..7338b5d4647c 100644
--- a/fs/ocfs2/dlm/dlmdomain.c
+++ b/fs/ocfs2/dlm/dlmdomain.c
@@ -1881,11 +1881,7 @@ static int dlm_join_domain(struct dlm_ctxt *dlm)
 		goto bail;
 	}
 
-	status = dlm_debug_init(dlm);
-	if (status < 0) {
-		mlog_errno(status);
-		goto bail;
-	}
+	dlm_debug_init(dlm);
 
 	snprintf(wq_name, O2NM_MAX_NAME_LEN, "dlm_wq-%s", dlm->name);
 	dlm->dlm_worker = alloc_workqueue(wq_name, WQ_MEM_RECLAIM, 0);
@@ -2346,9 +2342,7 @@ static int __init dlm_init(void)
 		goto error;
 	}
 
-	status = dlm_create_debugfs_root();
-	if (status)
-		goto error;
+	dlm_create_debugfs_root();
 
 	return 0;
 error: