debugfs: simplify __debugfs_remove_file()

mainline inclusion
from mainline-5.3-rc1
commit 823e545c027795997f29ec5c255aff605cf39e85
category: bugfix
bugzilla: 24454
CVE: MA

---------------------------

Move simple_unlink()+d_delete() from __debugfs_remove_file() into
caller __debugfs_remove() and rename helper for post remove file to
__debugfs_file_removed().

This will simplify adding fsnotify_unlink() hook.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NAmir Goldstein <amir73il@gmail.com>
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: Nyu kuai <yukuai3@huawei.com>
Reviewed-by: Nzhangyi (F) <yi.zhang@huawei.com>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>

fs/debugfs/inode.c

@@ -620,13 +620,10 @@ struct dentry *debugfs_create_symlink(const char *name, struct dentry *parent,
 }
 EXPORT_SYMBOL_GPL(debugfs_create_symlink);
 
-static void __debugfs_remove_file(struct dentry *dentry, struct dentry *parent)
+static void __debugfs_file_removed(struct dentry *dentry)
 {
 	struct debugfs_fsdata *fsd;
 
-	simple_unlink(d_inode(parent), dentry);
-	d_delete(dentry);
-
 	/*
 	 * Paired with the closing smp_mb() implied by a successful
 	 * cmpxchg() in debugfs_file_get(): either
@@ -647,16 +644,15 @@ static int __debugfs_remove(struct dentry *dentry, struct dentry *parent)
 
 	if (simple_positive(dentry)) {
 		dget(dentry);
-		if (!d_is_reg(dentry)) {
-			if (d_is_dir(dentry))
-				ret = simple_rmdir(d_inode(parent), dentry);
-			else
-				simple_unlink(d_inode(parent), dentry);
-			if (!ret)
-				d_delete(dentry);
+		if (d_is_dir(dentry)) {
+			ret = simple_rmdir(d_inode(parent), dentry);
 		} else {
-			__debugfs_remove_file(dentry, parent);
+			simple_unlink(d_inode(parent), dentry);
 		}
+		if (!ret)
+			d_delete(dentry);
+		if (d_is_reg(dentry))
+			__debugfs_file_removed(dentry);
 		dput(dentry);
 	}
 	return ret;