1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * include/linux/nfs_ssc.h
4 *
5 * Author: Dai Ngo <dai.ngo@oracle.com>
6 *
7 * Copyright (c) 2020, Oracle and/or its affiliates.
8 */
9
10#include <linux/nfs_fs.h>
11#include <linux/sunrpc/svc.h>
12
13extern struct nfs_ssc_client_ops_tbl nfs_ssc_client_tbl;
14
15/*
16 * NFS_V4
17 */
18struct nfs4_ssc_client_ops {
19	struct file *(*sco_open)(struct vfsmount *ss_mnt,
20		struct nfs_fh *src_fh, nfs4_stateid *stateid);
21	void (*sco_close)(struct file *filep);
22};
23
24/*
25 * NFS_FS
26 */
27struct nfs_ssc_client_ops {
28	void (*sco_sb_deactive)(struct super_block *sb);
29};
30
31struct nfs_ssc_client_ops_tbl {
32	const struct nfs4_ssc_client_ops *ssc_nfs4_ops;
33	const struct nfs_ssc_client_ops *ssc_nfs_ops;
34};
35
36extern void nfs42_ssc_register_ops(void);
37extern void nfs42_ssc_unregister_ops(void);
38
39extern void nfs42_ssc_register(const struct nfs4_ssc_client_ops *ops);
40extern void nfs42_ssc_unregister(const struct nfs4_ssc_client_ops *ops);
41
42#ifdef CONFIG_NFSD_V4_2_INTER_SSC
43static inline struct file *nfs42_ssc_open(struct vfsmount *ss_mnt,
44		struct nfs_fh *src_fh, nfs4_stateid *stateid)
45{
46	if (nfs_ssc_client_tbl.ssc_nfs4_ops)
47		return (*nfs_ssc_client_tbl.ssc_nfs4_ops->sco_open)(ss_mnt, src_fh, stateid);
48	return ERR_PTR(-EIO);
49}
50
51static inline void nfs42_ssc_close(struct file *filep)
52{
53	if (nfs_ssc_client_tbl.ssc_nfs4_ops)
54		(*nfs_ssc_client_tbl.ssc_nfs4_ops->sco_close)(filep);
55}
56#endif
57
58struct nfsd4_ssc_umount_item {
59	struct list_head nsui_list;
60	bool nsui_busy;
61	/*
62	 * nsui_refcnt inited to 2, 1 on list and 1 for consumer. Entry
63	 * is removed when refcnt drops to 1 and nsui_expire expires.
64	 */
65	refcount_t nsui_refcnt;
66	unsigned long nsui_expire;
67	struct vfsmount *nsui_vfsmount;
68	char nsui_ipaddr[RPC_MAX_ADDRBUFLEN + 1];
69};
70
71/*
72 * NFS_FS
73 */
74extern void nfs_ssc_register(const struct nfs_ssc_client_ops *ops);
75extern void nfs_ssc_unregister(const struct nfs_ssc_client_ops *ops);
76
77static inline void nfs_do_sb_deactive(struct super_block *sb)
78{
79	if (nfs_ssc_client_tbl.ssc_nfs_ops)
80		(*nfs_ssc_client_tbl.ssc_nfs_ops->sco_sb_deactive)(sb);
81}
82