f2fs: avoid potential unnecessary codes

This patch relocates some operations to avoid unnecessary execution.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index 2c0cb66..155885b 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -299,8 +299,6 @@
 	int need_update = true;
 
 	f2fs_bug_on(F2FS_I_SB(dn->inode), dn->data_blkaddr == NEW_ADDR);
-	fofs = start_bidx_of_node(ofs_of_node(dn->node_page), fi) +
-							dn->ofs_in_node;
 
 	/* Update the page address in the parent node */
 	__set_data_blkaddr(dn);
@@ -308,6 +306,9 @@
 	if (is_inode_flag_set(fi, FI_NO_EXTENT))
 		return;
 
+	fofs = start_bidx_of_node(ofs_of_node(dn->node_page), fi) +
+							dn->ofs_in_node;
+
 	write_lock(&fi->ext.ext_lock);
 
 	start_fofs = fi->ext.fofs;
diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
index a7cb0db2..9bed016 100644
--- a/fs/f2fs/node.c
+++ b/fs/f2fs/node.c
@@ -348,7 +348,6 @@
 	struct nat_entry *e;
 	int i;
 
-	memset(&ne, 0, sizeof(struct f2fs_nat_entry));
 	ni->nid = nid;
 
 	/* Check nat cache */
@@ -363,6 +362,8 @@
 	if (e)
 		return;
 
+	memset(&ne, 0, sizeof(struct f2fs_nat_entry));
+
 	/* Check current segment summary */
 	mutex_lock(&curseg->curseg_mutex);
 	i = lookup_journal_in_cursum(sum, NAT_JOURNAL, nid, 0);