nilfs2: make snapshots in checkpoint tree exportable
The previous export operations cannot handle multiple versions of
a filesystem if they belong to the same sb instance.
This adds a new type of file handle and extends export operations so
that they can get the inode specified by a checkpoint number as well
as an inode number and a generation number.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
diff --git a/fs/nilfs2/super.c b/fs/nilfs2/super.c
index a1c0e38..adbf582 100644
--- a/fs/nilfs2/super.c
+++ b/fs/nilfs2/super.c
@@ -48,10 +48,10 @@
#include <linux/vfs.h>
#include <linux/writeback.h>
#include <linux/kobject.h>
-#include <linux/exportfs.h>
#include <linux/seq_file.h>
#include <linux/mount.h>
#include "nilfs.h"
+#include "export.h"
#include "mdt.h"
#include "alloc.h"
#include "btree.h"
@@ -556,56 +556,6 @@
.show_options = nilfs_show_options
};
-static struct inode *
-nilfs_nfs_get_inode(struct super_block *sb, u64 ino, u32 generation)
-{
- struct inode *inode;
- struct nilfs_root *root;
-
- if (ino < NILFS_FIRST_INO(sb) && ino != NILFS_ROOT_INO &&
- ino != NILFS_SKETCH_INO)
- return ERR_PTR(-ESTALE);
-
- root = nilfs_lookup_root(NILFS_SB(sb)->s_nilfs,
- NILFS_CPTREE_CURRENT_CNO);
- if (!root)
- return ERR_PTR(-ESTALE);
-
- /* new file handle type is required to export snapshots */
- inode = nilfs_iget(sb, root, ino);
- nilfs_put_root(root);
- if (IS_ERR(inode))
- return ERR_CAST(inode);
- if (generation && inode->i_generation != generation) {
- iput(inode);
- return ERR_PTR(-ESTALE);
- }
-
- return inode;
-}
-
-static struct dentry *
-nilfs_fh_to_dentry(struct super_block *sb, struct fid *fid, int fh_len,
- int fh_type)
-{
- return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
- nilfs_nfs_get_inode);
-}
-
-static struct dentry *
-nilfs_fh_to_parent(struct super_block *sb, struct fid *fid, int fh_len,
- int fh_type)
-{
- return generic_fh_to_parent(sb, fid, fh_len, fh_type,
- nilfs_nfs_get_inode);
-}
-
-static const struct export_operations nilfs_export_ops = {
- .fh_to_dentry = nilfs_fh_to_dentry,
- .fh_to_parent = nilfs_fh_to_parent,
- .get_parent = nilfs_get_parent,
-};
-
enum {
Opt_err_cont, Opt_err_panic, Opt_err_ro,
Opt_barrier, Opt_nobarrier, Opt_snapshot, Opt_order, Opt_norecovery,