f2fs: use generic terms used for encrypted block management

This patch renames functions regarding to buffer management via META_MAPPING
used for encrypted blocks especially. We can actually use them in generic way.

Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

fs/f2fs/gc.c

@@ -599,8 +599,12 @@ static bool is_alive(struct f2fs_sb_info *sbi, struct f2fs_summary *sum,
 	return true;
 }
 
-static void move_encrypted_block(struct inode *inode, block_t bidx,
-							unsigned int segno, int off)
+/*
+ * Move data block via META_MAPPING while keeping locked data page.
+ * This can be used to move blocks, aka LBAs, directly on disk.
+ */
+static void move_data_block(struct inode *inode, block_t bidx,
+					unsigned int segno, int off)
 {
 	struct f2fs_io_info fio = {
 		.sbi = F2FS_I_SB(inode),
@@ -873,9 +877,10 @@ next_step:
 			start_bidx = start_bidx_of_node(nofs, inode)
 								+ ofs_in_node;
 			if (f2fs_encrypted_file(inode))
-				move_encrypted_block(inode, start_bidx, segno, off);
+				move_data_block(inode, start_bidx, segno, off);
 			else
-				move_data_page(inode, start_bidx, gc_type, segno, off);
+				move_data_page(inode, start_bidx, gc_type,
+								segno, off);
 
 			if (locked) {
 				up_write(&fi->dio_rwsem[WRITE]);