linux-kernel - [PATCH 3/3] f2fs: avoid reading NAT page by get_node

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Date:   Mon, 13 Feb 2017 18:06:44 -0800
From:   Jaegeuk Kim <jaegeuk@...nel.org>
To:     linux-kernel@...r.kernel.org, linux-fsdevel@...r.kernel.org,
        linux-f2fs-devel@...ts.sourceforge.net
Cc:     Jaegeuk Kim <jaegeuk@...nel.org>
Subject: [PATCH 3/3] f2fs: avoid reading NAT page by get_node_info

We've not seen this buggy case for a long time, so it's time to avoid this
unnecessary get_node_info() call which reading NAT page to cache nat entry.

Signed-off-by: Jaegeuk Kim <jaegeuk@...nel.org>
---
 fs/f2fs/node.c | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
index e001d084667f..b63bdb85ad66 100644
--- a/fs/f2fs/node.c
+++ b/fs/f2fs/node.c
@@ -1033,7 +1033,7 @@ struct page *new_node_page(struct dnode_of_data *dn,
 				unsigned int ofs, struct page *ipage)
 {
 	struct f2fs_sb_info *sbi = F2FS_I_SB(dn->inode);
-	struct node_info old_ni, new_ni;
+	struct node_info new_ni;
 	struct page *page;
 	int err;
 
@@ -1049,12 +1049,11 @@ struct page *new_node_page(struct dnode_of_data *dn,
 		goto fail;
 	}
 
-	get_node_info(sbi, dn->nid, &old_ni);
-
-	/* Reinitialize old_ni with new node page */
-	f2fs_bug_on(sbi, old_ni.blk_addr != NULL_ADDR);
-	new_ni = old_ni;
+	new_ni.nid = dn->nid;
 	new_ni.ino = dn->inode->i_ino;
+	new_ni.blk_addr = NULL_ADDR;
+	new_ni.flag = 0;
+	new_ni.version = 0;
 	set_node_addr(sbi, &new_ni, NEW_ADDR, false);
 
 	f2fs_wait_on_page_writeback(page, NODE, true);
-- 
2.11.0