exfat: remove NULL cache pointer case in exfat_ent_get

Since exfat_get_next_cluster has been updated, no callers pass a NULL
pointer to exfat_ent_get, so remove the handling logic for this case.

Signed-off-by: Chi Zhiling <chizhiling@kylinos.cn>
Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com>
Reviewed-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>

Author: Chi Zhiling

fs/exfat/fatent.c

@@ -44,20 +44,19 @@ static int exfat_end_bh(struct super_block *sb, struct buffer_head *bh)
 }
 
 static int __exfat_ent_get(struct super_block *sb, unsigned int loc,
-		unsigned int *content, struct buffer_head **last)
+		unsigned int *content, struct buffer_head **cache)
 {
 	unsigned int off;
 	sector_t sec;
-	struct buffer_head *bh = last ? *last : NULL;
+	struct buffer_head *bh = *cache;
 
 	sec = FAT_ENT_OFFSET_SECTOR(sb, loc);
 	off = FAT_ENT_OFFSET_BYTE_IN_SECTOR(sb, loc);
 
 	if (!bh || bh->b_blocknr != sec || !buffer_uptodate(bh)) {
 		brelse(bh);
 		bh = sb_bread(sb, sec);
-		if (last)
-			*last = bh;
+		*cache = bh;
 		if (unlikely(!bh))
 			return -EIO;
 	}
@@ -68,8 +67,6 @@ static int __exfat_ent_get(struct super_block *sb, unsigned int loc,
 	if (*content > EXFAT_BAD_CLUSTER)
 		*content = EXFAT_EOF_CLUSTER;
 
-	if (!last)
-		brelse(bh);
 	return 0;
 }
 
@@ -111,7 +108,7 @@ int exfat_ent_set(struct super_block *sb, unsigned int loc,
  * Caller must release the buffer_head if no error return.
  */
 int exfat_ent_get(struct super_block *sb, unsigned int loc,
-		unsigned int *content, struct buffer_head **last)
+		unsigned int *content, struct buffer_head **cache)
 {
 	struct exfat_sb_info *sbi = EXFAT_SB(sb);
 
@@ -122,7 +119,7 @@ int exfat_ent_get(struct super_block *sb, unsigned int loc,
 		goto err;
 	}
 
-	if (unlikely(__exfat_ent_get(sb, loc, content, last))) {
+	if (unlikely(__exfat_ent_get(sb, loc, content, cache))) {
 		exfat_fs_error_ratelimit(sb,
 			"failed to access to FAT (entry 0x%08x)",
 			loc);
@@ -151,13 +148,11 @@ int exfat_ent_get(struct super_block *sb, unsigned int loc,
 	}
 
 	return 0;
-err:
-	if (last) {
-		brelse(*last);
 
-		/* Avoid double release */
-		*last = NULL;
-	}
+err:
+	/* Avoid double release */
+	brelse(*cache);
+	*cache = NULL;
 	return -EIO;
 }