ext2: Match up ext2_put_page() with ext2_dotdot() and ext2_find_entry()

ext2_dotdot() and ext2_find_entry() both require ext2_put_page() to be
called after successful return.  For some of the calls this
corresponding put was hidden in ext2_set_link and ext2_delete_entry().

Match up ext2_put_page() with ext2_dotdot() and ext2_find_entry() in the
functions which call them.  This makes the code easier to follow
regarding the get/put of the page.

Clean up comments to match new behavior.

To: Jan Kara <jack@suse.com>
Link: https://lore.kernel.org/r/20210329065402.3297092-2-ira.weiny@intel.comSigned-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Jan Kara <jack@suse.cz>

fs/ext2/dir.c

@@ -434,7 +434,6 @@ static int ext2_prepare_chunk(struct page *page, loff_t pos, unsigned len)
 	return __block_write_begin(page, pos, len, ext2_get_block);
 }
 
-/* Releases the page */
 void ext2_set_link(struct inode *dir, struct ext2_dir_entry_2 *de,
 		   struct page *page, struct inode *inode, int update_times)
 {
@@ -449,7 +448,6 @@ void ext2_set_link(struct inode *dir, struct ext2_dir_entry_2 *de,
 	de->inode = cpu_to_le32(inode->i_ino);
 	ext2_set_de_type(de, inode);
 	err = ext2_commit_chunk(page, pos, len);
-	ext2_put_page(page);
 	if (update_times)
 		dir->i_mtime = dir->i_ctime = current_time(dir);
 	EXT2_I(dir)->i_flags &= ~EXT2_BTREE_FL;
@@ -556,7 +554,7 @@ int ext2_add_link (struct dentry *dentry, struct inode *inode)
 
 /*
  * ext2_delete_entry deletes a directory entry by merging it with the
- * previous entry. Page is up-to-date. Releases the page.
+ * previous entry. Page is up-to-date.
  */
 int ext2_delete_entry (struct ext2_dir_entry_2 * dir, struct page * page )
 {
@@ -594,7 +592,6 @@ int ext2_delete_entry (struct ext2_dir_entry_2 * dir, struct page * page )
 	EXT2_I(inode)->i_flags &= ~EXT2_BTREE_FL;
 	mark_inode_dirty(inode);
 out:
-	ext2_put_page(page);
 	return err;
 }
 

fs/ext2/namei.c

@@ -294,6 +294,7 @@ static int ext2_unlink(struct inode * dir, struct dentry *dentry)
 	}
 
 	err = ext2_delete_entry (de, page);
+	ext2_put_page(page);
 	if (err)
 		goto out;
 
@@ -371,6 +372,7 @@ static int ext2_rename (struct user_namespace * mnt_userns,
 			goto out_dir;
 		}
 		ext2_set_link(new_dir, new_de, new_page, old_inode, 1);
+		ext2_put_page(new_page);
 		new_inode->i_ctime = current_time(new_inode);
 		if (dir_de)
 			drop_nlink(new_inode);
@@ -391,12 +393,13 @@ static int ext2_rename (struct user_namespace * mnt_userns,
 	mark_inode_dirty(old_inode);
 
 	ext2_delete_entry (old_de, old_page);
+	ext2_put_page(old_page);
 
 	if (dir_de) {
 		if (old_dir != new_dir)
 			ext2_set_link(old_inode, dir_de, dir_page, new_dir, 0);
-		else
-			ext2_put_page(dir_page);
+
+		ext2_put_page(dir_page);
 		inode_dec_link_count(old_dir);
 	}
 	return 0;