super_block. This field must point to a "struct export_operations"
struct which has the following members:
- encode_fh (optional)
+ encode_fh (mandatory)
Takes a dentry and creates a filehandle fragment which may later be used
- to find or create a dentry for the same object. The default
- implementation creates a filehandle fragment that encodes a 32bit inode
- and generation number for the inode encoded, and if necessary the
- same information for the parent.
+ to find or create a dentry for the same object.
fh_to_dentry (mandatory)
Given a filehandle fragment, this should find the implied object and
As this is a VFS level change it has no practical consequences for filesystems
other than that all of them must use one of the provided kill_litter_super(),
kill_anon_super(), or kill_block_super() helpers.
+
+---
+
+**mandatory**
+
+export_operations ->encode_fh() no longer has a default implementation to
+encode FILEID_INO32_GEN* file handles.
+Filesystems that used the default implementation may use the generic helper
+generic_encode_ino32_fh() explicitly.
}
const struct export_operations affs_export_ops = {
+ .encode_fh = generic_encode_ino32_fh,
.fh_to_dentry = affs_fh_to_dentry,
.fh_to_parent = affs_fh_to_parent,
.get_parent = affs_get_parent,
};
static const struct export_operations befs_export_operations = {
+ .encode_fh = generic_encode_ino32_fh,
.fh_to_dentry = befs_fh_to_dentry,
.fh_to_parent = befs_fh_to_parent,
.get_parent = befs_get_parent,
};
static const struct export_operations efs_export_ops = {
+ .encode_fh = generic_encode_ino32_fh,
.fh_to_dentry = efs_fh_to_dentry,
.fh_to_parent = efs_fh_to_parent,
.get_parent = efs_get_parent,
}
static const struct export_operations erofs_export_ops = {
+ .encode_fh = generic_encode_ino32_fh,
.fh_to_dentry = erofs_fh_to_dentry,
.fh_to_parent = erofs_fh_to_parent,
.get_parent = erofs_get_parent,
}
/**
- * export_encode_fh - default export_operations->encode_fh function
+ * generic_encode_ino32_fh - generic export_operations->encode_fh function
* @inode: the object to encode
- * @fid: where to store the file handle fragment
- * @max_len: maximum length to store there
+ * @fh: where to store the file handle fragment
+ * @max_len: maximum length to store there (in 4 byte units)
* @parent: parent directory inode, if wanted
*
- * This default encode_fh function assumes that the 32 inode number
+ * This generic encode_fh function assumes that the 32 inode number
* is suitable for locating an inode, and that the generation number
* can be used to check that it is still valid. It places them in the
* filehandle fragment where export_decode_fh expects to find them.
*/
-static int export_encode_fh(struct inode *inode, struct fid *fid,
- int *max_len, struct inode *parent)
+int generic_encode_ino32_fh(struct inode *inode, __u32 *fh, int *max_len,
+ struct inode *parent)
{
+ struct fid *fid = (void *)fh;
int len = *max_len;
int type = FILEID_INO32_GEN;
*max_len = len;
return type;
}
+EXPORT_SYMBOL_GPL(generic_encode_ino32_fh);
/**
* exportfs_encode_inode_fh - encode a file handle from inode
if (nop && nop->encode_fh)
return nop->encode_fh(inode, fid->raw, max_len, parent);
- return export_encode_fh(inode, fid, max_len, parent);
+ return -EOPNOTSUPP;
}
EXPORT_SYMBOL_GPL(exportfs_encode_inode_fh);
}
static const struct export_operations ext2_export_ops = {
+ .encode_fh = generic_encode_ino32_fh,
.fh_to_dentry = ext2_fh_to_dentry,
.fh_to_parent = ext2_fh_to_parent,
.get_parent = ext2_get_parent,
};
static const struct export_operations ext4_export_ops = {
+ .encode_fh = generic_encode_ino32_fh,
.fh_to_dentry = ext4_fh_to_dentry,
.fh_to_parent = ext4_fh_to_parent,
.get_parent = ext4_get_parent,
}
static const struct export_operations f2fs_export_ops = {
+ .encode_fh = generic_encode_ino32_fh,
.fh_to_dentry = f2fs_fh_to_dentry,
.fh_to_parent = f2fs_fh_to_parent,
.get_parent = f2fs_get_parent,
}
const struct export_operations fat_export_ops = {
+ .encode_fh = generic_encode_ino32_fh,
.fh_to_dentry = fat_fh_to_dentry,
.fh_to_parent = fat_fh_to_parent,
.get_parent = fat_get_parent,
}
static const struct export_operations jffs2_export_ops = {
+ .encode_fh = generic_encode_ino32_fh,
.get_parent = jffs2_get_parent,
.fh_to_dentry = jffs2_fh_to_dentry,
.fh_to_parent = jffs2_fh_to_parent,
};
static const struct export_operations jfs_export_operations = {
+ .encode_fh = generic_encode_ino32_fh,
.fh_to_dentry = jfs_fh_to_dentry,
.fh_to_parent = jfs_fh_to_parent,
.get_parent = jfs_get_parent,
* and due to using iget() whereas NTFS needs ntfs_iget().
*/
const struct export_operations ntfs_export_ops = {
+ .encode_fh = generic_encode_ino32_fh,
.get_parent = ntfs_get_parent, /* Find the parent of a given
directory. */
.fh_to_dentry = ntfs_fh_to_dentry,
}
static const struct export_operations ntfs_export_ops = {
+ .encode_fh = generic_encode_ino32_fh,
.fh_to_dentry = ntfs_fh_to_dentry,
.fh_to_parent = ntfs_fh_to_parent,
.get_parent = ntfs3_get_parent,
}
const struct export_operations cifs_export_ops = {
+ .encode_fh = generic_encode_ino32_fh,
.get_parent = cifs_get_parent,
-/* Following five export operations are unneeded so far and can default:
- .get_dentry =
- .get_name =
- .find_exported_dentry =
- .decode_fh =
- .encode_fs = */
+/*
+ * Following export operations are mandatory for NFS export support:
+ * .fh_to_dentry =
+ */
};
#endif /* CONFIG_CIFS_NFSD_EXPORT */
const struct export_operations squashfs_export_ops = {
+ .encode_fh = generic_encode_ino32_fh,
.fh_to_dentry = squashfs_fh_to_dentry,
.fh_to_parent = squashfs_fh_to_parent,
.get_parent = squashfs_get_parent
}
static const struct export_operations ufs_export_ops = {
+ .encode_fh = generic_encode_ino32_fh,
.fh_to_dentry = ufs_fh_to_dentry,
.fh_to_parent = ufs_fh_to_parent,
.get_parent = ufs_get_parent,
static inline bool exportfs_can_encode_fid(const struct export_operations *nop)
{
- return nop;
+ return nop && nop->encode_fh;
}
static inline bool exportfs_can_decode_fh(const struct export_operations *nop)
/*
* Generic helpers for filesystems.
*/
+#ifdef CONFIG_EXPORTFS
+int generic_encode_ino32_fh(struct inode *inode, __u32 *fh, int *max_len,
+ struct inode *parent);
+#else
+#define generic_encode_ino32_fh NULL
+#endif
+
extern struct dentry *generic_fh_to_dentry(struct super_block *sb,
struct fid *fid, int fh_len, int fh_type,
struct inode *(*get_inode) (struct super_block *sb, u64 ino, u32 gen));