nilfs2: simplify remaining sget() use

This simplifies the test function passed on the remaining sget()
callsite in nilfs.

Instead of checking mount type (i.e. ro-mount/rw-mount/snapshot mount)
in the test function passed to sget(), this patch first looks up the
nilfs_sb_info struct which the given mount type matches, and then
acquires the super block instance holding the nilfs_sb_info.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 1 insertions, 0 deletions

diff --git a/fs/nilfs2/sb.h b/fs/nilfs2/sb.h
index adccd4fc654e..0776ccc2504a 100644
--- a/fs/nilfs2/sb.h
+++ b/fs/nilfs2/sb.h
@@ -60,6 +60,7 @@ struct nilfs_sb_info {
         struct super_block *s_super;    /* reverse pointer to super_block */
         struct the_nilfs *s_nilfs;
         struct list_head s_list;        /* list head for nilfs->ns_supers */
+        atomic_t s_count;               /* reference count */
 
         /* Segment constructor */
         struct list_head s_dirty_files; /* dirty files list */