nilfs2: split out nilfs_attach_snapshot
This splits the code to attach snapshots into a separate routine for
convenience sake.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
diff --git a/fs/nilfs2/super.c b/fs/nilfs2/super.c
index 1e12930..ebeb746 100644
--- a/fs/nilfs2/super.c
+++ b/fs/nilfs2/super.c
@@ -783,6 +783,40 @@
return ret;
}
+static int nilfs_attach_snapshot(struct super_block *s, __u64 cno,
+ struct dentry **root_dentry)
+{
+ struct the_nilfs *nilfs = NILFS_SB(s)->s_nilfs;
+ struct nilfs_root *root;
+ int ret;
+
+ down_read(&nilfs->ns_segctor_sem);
+ ret = nilfs_cpfile_is_snapshot(nilfs->ns_cpfile, cno);
+ up_read(&nilfs->ns_segctor_sem);
+ if (ret < 0) {
+ ret = (ret == -ENOENT) ? -EINVAL : ret;
+ goto out;
+ } else if (!ret) {
+ printk(KERN_ERR "NILFS: The specified checkpoint is "
+ "not a snapshot (checkpoint number=%llu).\n",
+ (unsigned long long)cno);
+ ret = -EINVAL;
+ goto out;
+ }
+
+ ret = nilfs_attach_checkpoint(NILFS_SB(s), cno, false, &root);
+ if (ret) {
+ printk(KERN_ERR "NILFS: error loading snapshot "
+ "(checkpoint number=%llu).\n",
+ (unsigned long long)cno);
+ goto out;
+ }
+ ret = nilfs_get_root_dentry(s, root, root_dentry);
+ nilfs_put_root(root);
+ out:
+ return ret;
+}
+
/**
* nilfs_fill_super() - initialize a super block instance
* @sb: super_block
@@ -800,7 +834,7 @@
struct nilfs_sb_info *sbi;
struct nilfs_root *fsroot;
__u64 cno;
- int err, curr_mnt;
+ int err;
sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
if (!sbi)
@@ -841,35 +875,17 @@
if (err)
goto failed_sbi;
- cno = nilfs_last_cno(nilfs);
- curr_mnt = true;
+ if (nilfs_test_opt(sbi, SNAPSHOT)) {
+ err = nilfs_attach_snapshot(sb, sbi->s_snapshot_cno,
+ &sb->s_root);
+ if (err)
+ goto failed_sbi;
- if (sb->s_flags & MS_RDONLY) {
- if (nilfs_test_opt(sbi, SNAPSHOT)) {
- down_read(&nilfs->ns_segctor_sem);
- err = nilfs_cpfile_is_snapshot(nilfs->ns_cpfile,
- sbi->s_snapshot_cno);
- up_read(&nilfs->ns_segctor_sem);
- if (err < 0) {
- if (err == -ENOENT)
- err = -EINVAL;
- goto failed_sbi;
- }
- if (!err) {
- printk(KERN_ERR
- "NILFS: The specified checkpoint is "
- "not a snapshot "
- "(checkpoint number=%llu).\n",
- (unsigned long long)sbi->s_snapshot_cno);
- err = -EINVAL;
- goto failed_sbi;
- }
- cno = sbi->s_snapshot_cno;
- curr_mnt = false;
- }
+ goto add_to_supers;
}
- err = nilfs_attach_checkpoint(sbi, cno, curr_mnt, &fsroot);
+ cno = nilfs_last_cno(nilfs);
+ err = nilfs_attach_checkpoint(sbi, cno, true, &fsroot);
if (err) {
printk(KERN_ERR "NILFS: error loading a checkpoint"
" (checkpoint number=%llu).\n", (unsigned long long)cno);
@@ -894,6 +910,7 @@
up_write(&nilfs->ns_sem);
}
+ add_to_supers:
down_write(&nilfs->ns_super_sem);
list_add(&sbi->s_list, &nilfs->ns_supers);
if (!nilfs_test_opt(sbi, SNAPSHOT))