Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ryusuke/nilfs2

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ryusuke/nilfs2:
  nilfs2: fix oopses with doubly mounted snapshots
  nilfs2: missing a read lock for segment writer in nilfs_attach_checkpoint()

2 files changed, 3 insertions, 1 deletions

diff --git a/fs/nilfs2/super.c b/fs/nilfs2/super.c
index 8e2ec43b18f4..151964f0de4c 100644
--- a/fs/nilfs2/super.c
+++ b/fs/nilfs2/super.c
@@ -416,8 +416,10 @@ int nilfs_attach_checkpoint(struct nilfs_sb_info *sbi, __u64 cno)
         if (unlikely(err))
                 goto failed;
 
+        down_read(&nilfs->ns_segctor_sem);
         err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, cno, 0, &raw_cp,
                                           &bh_cp);
+        up_read(&nilfs->ns_segctor_sem);
         if (unlikely(err)) {
                 if (err == -ENOENT || err == -EINVAL) {
                         printk(KERN_ERR
diff --git a/fs/nilfs2/the_nilfs.h b/fs/nilfs2/the_nilfs.h
index e8adbffc626f..1b9caafb8662 100644
--- a/fs/nilfs2/the_nilfs.h
+++ b/fs/nilfs2/the_nilfs.h
@@ -253,7 +253,7 @@ nilfs_detach_writer(struct the_nilfs *nilfs, struct nilfs_sb_info *sbi)
 
 static inline void nilfs_put_sbinfo(struct nilfs_sb_info *sbi)
 {
-        if (!atomic_dec_and_test(&sbi->s_count))
+        if (atomic_dec_and_test(&sbi->s_count))
                 kfree(sbi);
 }