[PATCH 6/8] nilfs2: fix wrong accounting and duplicate brelse in nilfs_sufile_set_error

[Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>]

The nilfs_sufile_set_error() function wrongly adjusts the number of
dirty segments instead of the number of clean segments.  In addition,
the function calls brelse() twice for the same buffer head.

This fixes these bugs.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
---
 fs/nilfs2/sufile.c |   17 ++++++++++-------
 1 files changed, 10 insertions(+), 7 deletions(-)

diff --git a/fs/nilfs2/sufile.c b/fs/nilfs2/sufile.c
index 1ef2b4d..8b2f93c 100644
--- a/fs/nilfs2/sufile.c
+++ b/fs/nilfs2/sufile.c
@@ -523,7 +523,7 @@ int nilfs_sufile_set_error(struct inode *sufile, __u64 segnum)
 	struct nilfs_segment_usage *su;
 	struct nilfs_sufile_header *header;
 	void *kaddr;
-	int ret;
+	int suclean, ret;
 
 	if (unlikely(segnum >= nilfs_sufile_get_nsegments(sufile))) {
 		printk(KERN_WARNING "%s: invalid segment number: %llu\n",
@@ -546,16 +546,19 @@ int nilfs_sufile_set_error(struct inode *sufile, __u64 segnum)
 		brelse(su_bh);
 		goto out_header;
 	}
+	suclean = nilfs_segment_usage_clean(su);
 
 	nilfs_segment_usage_set_error(su);
 	kunmap_atomic(kaddr, KM_USER0);
-	brelse(su_bh);
 
-	kaddr = kmap_atomic(header_bh->b_page, KM_USER0);
-	header = nilfs_sufile_block_get_header(sufile, header_bh, kaddr);
-	le64_add_cpu(&header->sh_ndirtysegs, -1);
-	kunmap_atomic(kaddr, KM_USER0);
-	nilfs_mdt_mark_buffer_dirty(header_bh);
+	if (suclean) {
+		kaddr = kmap_atomic(header_bh->b_page, KM_USER0);
+		header = nilfs_sufile_block_get_header(sufile, header_bh,
+						       kaddr);
+		le64_add_cpu(&header->sh_ncleansegs, -1);
+		kunmap_atomic(kaddr, KM_USER0);
+		nilfs_mdt_mark_buffer_dirty(header_bh);
+	}
 	nilfs_mdt_mark_buffer_dirty(su_bh);
 	nilfs_mdt_mark_dirty(sufile);
 	brelse(su_bh);
-- 
1.5.6.5