[PATCH] ubifs: no need to check return value of debugfs_create functions

Greg Kroah-Hartman gregkh at linuxfoundation.org
Wed Jun 12 08:21:20 PDT 2019


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.

Cc: Richard Weinberger <richard at nod.at>
Cc: Artem Bityutskiy <dedekind1 at gmail.com>
Cc: Adrian Hunter <adrian.hunter at intel.com>
Cc: linux-mtd at lists.infradead.org
Signed-off-by: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
---
 fs/ubifs/debug.c | 167 ++++++++++++-----------------------------------
 fs/ubifs/debug.h |   4 +-
 fs/ubifs/super.c |   9 +--
 3 files changed, 45 insertions(+), 135 deletions(-)

diff --git a/fs/ubifs/debug.c b/fs/ubifs/debug.c
index 3a2613038e88..57e6fcb043ca 100644
--- a/fs/ubifs/debug.c
+++ b/fs/ubifs/debug.c
@@ -2812,115 +2812,69 @@ static const struct file_operations dfs_fops = {
  * dbg_debugfs_init_fs - initialize debugfs for UBIFS instance.
  * @c: UBIFS file-system description object
  *
- * This function creates all debugfs files for this instance of UBIFS. Returns
- * zero in case of success and a negative error code in case of failure.
+ * This function creates all debugfs files for this instance of UBIFS.
  *
  * Note, the only reason we have not merged this function with the
  * 'ubifs_debugging_init()' function is because it is better to initialize
  * debugfs interfaces at the very end of the mount process, and remove them at
  * the very beginning of the mount process.
  */
-int dbg_debugfs_init_fs(struct ubifs_info *c)
+void dbg_debugfs_init_fs(struct ubifs_info *c)
 {
 	int err, n;
 	const char *fname;
-	struct dentry *dent;
 	struct ubifs_debug_info *d = c->dbg;
 
-	if (!IS_ENABLED(CONFIG_DEBUG_FS))
-		return 0;
-
 	n = snprintf(d->dfs_dir_name, UBIFS_DFS_DIR_LEN + 1, UBIFS_DFS_DIR_NAME,
 		     c->vi.ubi_num, c->vi.vol_id);
 	if (n == UBIFS_DFS_DIR_LEN) {
 		/* The array size is too small */
 		fname = UBIFS_DFS_DIR_NAME;
-		dent = ERR_PTR(-EINVAL);
-		goto out;
+		return;
 	}
 
 	fname = d->dfs_dir_name;
-	dent = debugfs_create_dir(fname, dfs_rootdir);
-	if (IS_ERR_OR_NULL(dent))
-		goto out;
-	d->dfs_dir = dent;
+	d->dfs_dir = debugfs_create_dir(fname, dfs_rootdir);
 
 	fname = "dump_lprops";
-	dent = debugfs_create_file(fname, S_IWUSR, d->dfs_dir, c, &dfs_fops);
-	if (IS_ERR_OR_NULL(dent))
-		goto out_remove;
-	d->dfs_dump_lprops = dent;
+	d->dfs_dump_lprops = debugfs_create_file(fname, S_IWUSR, d->dfs_dir, c,
+						 &dfs_fops);
 
 	fname = "dump_budg";
-	dent = debugfs_create_file(fname, S_IWUSR, d->dfs_dir, c, &dfs_fops);
-	if (IS_ERR_OR_NULL(dent))
-		goto out_remove;
-	d->dfs_dump_budg = dent;
+	d->dfs_dump_budg = debugfs_create_file(fname, S_IWUSR, d->dfs_dir, c,
+					       &dfs_fops);
 
 	fname = "dump_tnc";
-	dent = debugfs_create_file(fname, S_IWUSR, d->dfs_dir, c, &dfs_fops);
-	if (IS_ERR_OR_NULL(dent))
-		goto out_remove;
-	d->dfs_dump_tnc = dent;
+	d->dfs_dump_tnc = debugfs_create_file(fname, S_IWUSR, d->dfs_dir, c,
+					      &dfs_fops);
 
 	fname = "chk_general";
-	dent = debugfs_create_file(fname, S_IRUSR | S_IWUSR, d->dfs_dir, c,
-				   &dfs_fops);
-	if (IS_ERR_OR_NULL(dent))
-		goto out_remove;
-	d->dfs_chk_gen = dent;
+	d->dfs_chk_gen = debugfs_create_file(fname, S_IRUSR | S_IWUSR,
+					     d->dfs_dir, c, &dfs_fops);
 
 	fname = "chk_index";
-	dent = debugfs_create_file(fname, S_IRUSR | S_IWUSR, d->dfs_dir, c,
-				   &dfs_fops);
-	if (IS_ERR_OR_NULL(dent))
-		goto out_remove;
-	d->dfs_chk_index = dent;
+	d->dfs_chk_index = debugfs_create_file(fname, S_IRUSR | S_IWUSR,
+					       d->dfs_dir, c, &dfs_fops);
 
 	fname = "chk_orphans";
-	dent = debugfs_create_file(fname, S_IRUSR | S_IWUSR, d->dfs_dir, c,
-				   &dfs_fops);
-	if (IS_ERR_OR_NULL(dent))
-		goto out_remove;
-	d->dfs_chk_orph = dent;
+	d->dfs_chk_orph = debugfs_create_file(fname, S_IRUSR | S_IWUSR,
+					      d->dfs_dir, c, &dfs_fops);
 
 	fname = "chk_lprops";
-	dent = debugfs_create_file(fname, S_IRUSR | S_IWUSR, d->dfs_dir, c,
-				   &dfs_fops);
-	if (IS_ERR_OR_NULL(dent))
-		goto out_remove;
-	d->dfs_chk_lprops = dent;
+	d->dfs_chk_lprops = debugfs_create_file(fname, S_IRUSR | S_IWUSR,
+						d->dfs_dir, c, &dfs_fops);
 
 	fname = "chk_fs";
-	dent = debugfs_create_file(fname, S_IRUSR | S_IWUSR, d->dfs_dir, c,
-				   &dfs_fops);
-	if (IS_ERR_OR_NULL(dent))
-		goto out_remove;
-	d->dfs_chk_fs = dent;
+	d->dfs_chk_fs = debugfs_create_file(fname, S_IRUSR | S_IWUSR,
+					    d->dfs_dir, c, &dfs_fops);
 
 	fname = "tst_recovery";
-	dent = debugfs_create_file(fname, S_IRUSR | S_IWUSR, d->dfs_dir, c,
-				   &dfs_fops);
-	if (IS_ERR_OR_NULL(dent))
-		goto out_remove;
-	d->dfs_tst_rcvry = dent;
+	d->dfs_tst_rcvry = debugfs_create_file(fname, S_IRUSR | S_IWUSR,
+					       d->dfs_dir, c, &dfs_fops);
 
 	fname = "ro_error";
-	dent = debugfs_create_file(fname, S_IRUSR | S_IWUSR, d->dfs_dir, c,
-				   &dfs_fops);
-	if (IS_ERR_OR_NULL(dent))
-		goto out_remove;
-	d->dfs_ro_error = dent;
-
-	return 0;
-
-out_remove:
-	debugfs_remove_recursive(d->dfs_dir);
-out:
-	err = dent ? PTR_ERR(dent) : -ENODEV;
-	ubifs_err(c, "cannot create \"%s\" debugfs file or directory, error %d\n",
-		  fname, err);
-	return err;
+	d->dfs_ro_error = debugfs_create_file(fname, S_IRUSR | S_IWUSR,
+					      d->dfs_dir, c, &dfs_fops);
 }
 
 /**
@@ -2929,8 +2883,7 @@ int dbg_debugfs_init_fs(struct ubifs_info *c)
  */
 void dbg_debugfs_exit_fs(struct ubifs_info *c)
 {
-	if (IS_ENABLED(CONFIG_DEBUG_FS))
-		debugfs_remove_recursive(c->dbg->dfs_dir);
+	debugfs_remove_recursive(c->dbg->dfs_dir);
 }
 
 struct ubifs_global_debug_info ubifs_dbg;
@@ -3006,75 +2959,38 @@ static const struct file_operations dfs_global_fops = {
  *
  * UBIFS uses debugfs file-system to expose various debugging knobs to
  * user-space. This function creates "ubifs" directory in the debugfs
- * file-system. Returns zero in case of success and a negative error code in
- * case of failure.
+ * file-system.
  */
-int dbg_debugfs_init(void)
+void dbg_debugfs_init(void)
 {
-	int err;
 	const char *fname;
-	struct dentry *dent;
-
-	if (!IS_ENABLED(CONFIG_DEBUG_FS))
-		return 0;
 
 	fname = "ubifs";
-	dent = debugfs_create_dir(fname, NULL);
-	if (IS_ERR_OR_NULL(dent))
-		goto out;
-	dfs_rootdir = dent;
+	dfs_rootdir = debugfs_create_dir(fname, NULL);
 
 	fname = "chk_general";
-	dent = debugfs_create_file(fname, S_IRUSR | S_IWUSR, dfs_rootdir, NULL,
-				   &dfs_global_fops);
-	if (IS_ERR_OR_NULL(dent))
-		goto out_remove;
-	dfs_chk_gen = dent;
+	dfs_chk_gen = debugfs_create_file(fname, S_IRUSR | S_IWUSR, dfs_rootdir,
+					  NULL, &dfs_global_fops);
 
 	fname = "chk_index";
-	dent = debugfs_create_file(fname, S_IRUSR | S_IWUSR, dfs_rootdir, NULL,
-				   &dfs_global_fops);
-	if (IS_ERR_OR_NULL(dent))
-		goto out_remove;
-	dfs_chk_index = dent;
+	dfs_chk_index = debugfs_create_file(fname, S_IRUSR | S_IWUSR,
+					    dfs_rootdir, NULL, &dfs_global_fops);
 
 	fname = "chk_orphans";
-	dent = debugfs_create_file(fname, S_IRUSR | S_IWUSR, dfs_rootdir, NULL,
-				   &dfs_global_fops);
-	if (IS_ERR_OR_NULL(dent))
-		goto out_remove;
-	dfs_chk_orph = dent;
+	dfs_chk_orph = debugfs_create_file(fname, S_IRUSR | S_IWUSR,
+					   dfs_rootdir, NULL, &dfs_global_fops);
 
 	fname = "chk_lprops";
-	dent = debugfs_create_file(fname, S_IRUSR | S_IWUSR, dfs_rootdir, NULL,
-				   &dfs_global_fops);
-	if (IS_ERR_OR_NULL(dent))
-		goto out_remove;
-	dfs_chk_lprops = dent;
+	dfs_chk_lprops = debugfs_create_file(fname, S_IRUSR | S_IWUSR,
+					     dfs_rootdir, NULL, &dfs_global_fops);
 
 	fname = "chk_fs";
-	dent = debugfs_create_file(fname, S_IRUSR | S_IWUSR, dfs_rootdir, NULL,
-				   &dfs_global_fops);
-	if (IS_ERR_OR_NULL(dent))
-		goto out_remove;
-	dfs_chk_fs = dent;
+	dfs_chk_fs = debugfs_create_file(fname, S_IRUSR | S_IWUSR, dfs_rootdir,
+					 NULL, &dfs_global_fops);
 
 	fname = "tst_recovery";
-	dent = debugfs_create_file(fname, S_IRUSR | S_IWUSR, dfs_rootdir, NULL,
-				   &dfs_global_fops);
-	if (IS_ERR_OR_NULL(dent))
-		goto out_remove;
-	dfs_tst_rcvry = dent;
-
-	return 0;
-
-out_remove:
-	debugfs_remove_recursive(dfs_rootdir);
-out:
-	err = dent ? PTR_ERR(dent) : -ENODEV;
-	pr_err("UBIFS error (pid %d): cannot create \"%s\" debugfs file or directory, error %d\n",
-	       current->pid, fname, err);
-	return err;
+	dfs_tst_rcvry = debugfs_create_file(fname, S_IRUSR | S_IWUSR,
+					    dfs_rootdir, NULL, &dfs_global_fops);
 }
 
 /**
@@ -3082,8 +2998,7 @@ int dbg_debugfs_init(void)
  */
 void dbg_debugfs_exit(void)
 {
-	if (IS_ENABLED(CONFIG_DEBUG_FS))
-		debugfs_remove_recursive(dfs_rootdir);
+	debugfs_remove_recursive(dfs_rootdir);
 }
 
 void ubifs_assert_failed(struct ubifs_info *c, const char *expr,
diff --git a/fs/ubifs/debug.h b/fs/ubifs/debug.h
index 64c6977c189b..c6c8f1b62af5 100644
--- a/fs/ubifs/debug.h
+++ b/fs/ubifs/debug.h
@@ -309,9 +309,9 @@ int dbg_leb_unmap(struct ubifs_info *c, int lnum);
 int dbg_leb_map(struct ubifs_info *c, int lnum);
 
 /* Debugfs-related stuff */
-int dbg_debugfs_init(void);
+void dbg_debugfs_init(void);
 void dbg_debugfs_exit(void);
-int dbg_debugfs_init_fs(struct ubifs_info *c);
+void dbg_debugfs_init_fs(struct ubifs_info *c);
 void dbg_debugfs_exit_fs(struct ubifs_info *c);
 
 #endif /* !__UBIFS_DEBUG_H__ */
diff --git a/fs/ubifs/super.c b/fs/ubifs/super.c
index 04b8ecfd3470..2429906bd681 100644
--- a/fs/ubifs/super.c
+++ b/fs/ubifs/super.c
@@ -1477,9 +1477,7 @@ static int mount_ubifs(struct ubifs_info *c)
 	if (err)
 		goto out_infos;
 
-	err = dbg_debugfs_init_fs(c);
-	if (err)
-		goto out_infos;
+	dbg_debugfs_init_fs(c);
 
 	c->mounting = 0;
 
@@ -2364,9 +2362,7 @@ static int __init ubifs_init(void)
 	if (err)
 		goto out_shrinker;
 
-	err = dbg_debugfs_init();
-	if (err)
-		goto out_compr;
+	dbg_debugfs_init();
 
 	err = register_filesystem(&ubifs_fs_type);
 	if (err) {
@@ -2378,7 +2374,6 @@ static int __init ubifs_init(void)
 
 out_dbg:
 	dbg_debugfs_exit();
-out_compr:
 	ubifs_compressors_exit();
 out_shrinker:
 	unregister_shrinker(&ubifs_shrinker_info);
-- 
2.22.0




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