diff options
Diffstat (limited to 'fs/nilfs2/cpfile.c')
| -rw-r--r-- | fs/nilfs2/cpfile.c | 13 |
1 files changed, 8 insertions, 5 deletions
diff --git a/fs/nilfs2/cpfile.c b/fs/nilfs2/cpfile.c index aec942cf79e3..3f5d5d06f53c 100644 --- a/fs/nilfs2/cpfile.c +++ b/fs/nilfs2/cpfile.c @@ -815,8 +815,10 @@ int nilfs_cpfile_is_snapshot(struct inode *cpfile, __u64 cno) void *kaddr; int ret; - if (cno == 0) - return -ENOENT; /* checkpoint number 0 is invalid */ + /* CP number is invalid if it's zero or larger than the + largest exist one.*/ + if (cno == 0 || cno >= nilfs_mdt_cno(cpfile)) + return -ENOENT; down_read(&NILFS_MDT(cpfile)->mi_sem); ret = nilfs_cpfile_get_checkpoint_block(cpfile, cno, 0, &bh); @@ -824,7 +826,10 @@ int nilfs_cpfile_is_snapshot(struct inode *cpfile, __u64 cno) goto out; kaddr = kmap_atomic(bh->b_page, KM_USER0); cp = nilfs_cpfile_block_get_checkpoint(cpfile, cno, bh, kaddr); - ret = nilfs_checkpoint_snapshot(cp); + if (nilfs_checkpoint_invalid(cp)) + ret = -ENOENT; + else + ret = nilfs_checkpoint_snapshot(cp); kunmap_atomic(kaddr, KM_USER0); brelse(bh); @@ -866,7 +871,6 @@ int nilfs_cpfile_change_cpmode(struct inode *cpfile, __u64 cno, int mode) * exclusive with a new mount job. Though it doesn't cover * umount, it's enough for the purpose. */ - mutex_lock(&nilfs->ns_mount_mutex); if (nilfs_checkpoint_is_mounted(nilfs, cno, 1)) { /* Current implementation does not have to protect plain read-only mounts since they are exclusive @@ -875,7 +879,6 @@ int nilfs_cpfile_change_cpmode(struct inode *cpfile, __u64 cno, int mode) ret = -EBUSY; } else ret = nilfs_cpfile_clear_snapshot(cpfile, cno); - mutex_unlock(&nilfs->ns_mount_mutex); return ret; case NILFS_SNAPSHOT: return nilfs_cpfile_set_snapshot(cpfile, cno); |
