From 4dc7d35e09ba78aa0a3bcaa9fad1c19952e018a7 Mon Sep 17 00:00:00 2001
From: Tetsuhiro Kohada <kohada.t2@gmail.com>
Date: Wed, 24 Jun 2020 11:30:40 +0900
Subject: [Backport 4dc7d35e09ba] exfat: optimize exfat_zeroed_cluster()

Replace part of exfat_zeroed_cluster() with exfat_update_bhs().
And remove exfat_sync_bhs().

Signed-off-by: Tetsuhiro Kohada <kohada.t2@gmail.com>
Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
---
 src/fatent.c | 53 +++++++++--------------------------------------
 1 file changed, 10 insertions(+), 43 deletions(-)

diff --git a/src/fatent.c b/src/fatent.c
index 82ee8246c080f38bc2cc0f8074c72aebbff03fd8..c3c9afee7418f1871a65757d79f8d4a13fe650c2 100644
--- a/src/fatent.c
+++ b/src/fatent.c
@@ -229,21 +229,6 @@ int exfat_find_last_cluster(struct super_block *sb, struct exfat_chain *p_chain,
 	return 0;
 }
 
-static inline int exfat_sync_bhs(struct buffer_head **bhs, int nr_bhs)
-{
-	int i, err = 0;
-
-	for (i = 0; i < nr_bhs; i++)
-		write_dirty_buffer(bhs[i], 0);
-
-	for (i = 0; i < nr_bhs; i++) {
-		wait_on_buffer(bhs[i]);
-		if (!err && !buffer_uptodate(bhs[i]))
-			err = -EIO;
-	}
-	return err;
-}
-
 int exfat_zeroed_cluster(struct inode *dir, unsigned int clu)
 {
 	struct super_block *sb = dir->i_sb;
@@ -265,41 +250,23 @@ int exfat_zeroed_cluster(struct inode *dir, unsigned int clu)
 	}
 
 	/* Zeroing the unused blocks on this cluster */
-	n = 0;
 	while (blknr < last_blknr) {
-		bhs[n] = sb_getblk(sb, blknr);
-		if (!bhs[n]) {
-			err = -ENOMEM;
-			goto release_bhs;
-		}
-		memset(bhs[n]->b_data, 0, sb->s_blocksize);
-		exfat_update_bh(bhs[n], 0);
-
-		n++;
-		blknr++;
-
-		if (n == nr_bhs) {
-			if (IS_DIRSYNC(dir)) {
-				err = exfat_sync_bhs(bhs, n);
-				if (err)
-					goto release_bhs;
+		for (n = 0; n < nr_bhs && blknr < last_blknr; n++, blknr++) {
+			bhs[n] = sb_getblk(sb, blknr);
+			if (!bhs[n]) {
+				err = -ENOMEM;
+				goto release_bhs;
 			}
-
-			for (i = 0; i < n; i++)
-				brelse(bhs[i]);
-			n = 0;
+			memset(bhs[n]->b_data, 0, sb->s_blocksize);
 		}
-	}
 
-	if (IS_DIRSYNC(dir)) {
-		err = exfat_sync_bhs(bhs, n);
+		err = exfat_update_bhs(bhs, n, IS_DIRSYNC(dir));
 		if (err)
 			goto release_bhs;
-	}
-
-	for (i = 0; i < n; i++)
-		brelse(bhs[i]);
 
+		for (i = 0; i < n; i++)
+			brelse(bhs[i]);
+	}
 	return 0;
 
 release_bhs:
-- 
2.31.1