1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * Copyright (C) 2024 Mike Snitzer <snitzer@hammerspace.com>
4 * Copyright (C) 2024 NeilBrown <neilb@suse.de>
5 */
6 #ifndef __LINUX_NFSLOCALIO_H
7 #define __LINUX_NFSLOCALIO_H
8
9 /* nfsd_file structure is purposely kept opaque to NFS client */
10 struct nfsd_file;
11
12 #if IS_ENABLED(CONFIG_NFS_LOCALIO)
13
14 #include <linux/module.h>
15 #include <linux/list.h>
16 #include <linux/uuid.h>
17 #include <linux/sunrpc/clnt.h>
18 #include <linux/sunrpc/svcauth.h>
19 #include <linux/nfs.h>
20 #include <net/net_namespace.h>
21
22 /*
23 * Useful to allow a client to negotiate if localio
24 * possible with its server.
25 *
26 * See Documentation/filesystems/nfs/localio.rst for more detail.
27 */
28 typedef struct {
29 uuid_t uuid;
30 struct list_head list;
31 struct net __rcu *net; /* nfsd's network namespace */
32 struct auth_domain *dom; /* auth_domain for localio */
33 } nfs_uuid_t;
34
35 void nfs_uuid_init(nfs_uuid_t *);
36 bool nfs_uuid_begin(nfs_uuid_t *);
37 void nfs_uuid_end(nfs_uuid_t *);
38 void nfs_uuid_is_local(const uuid_t *, struct list_head *,
39 struct net *, struct auth_domain *, struct module *);
40 void nfs_uuid_invalidate_clients(struct list_head *list);
41 void nfs_uuid_invalidate_one_client(nfs_uuid_t *nfs_uuid);
42
43 /* localio needs to map filehandle -> struct nfsd_file */
44 extern struct nfsd_file *
45 nfsd_open_local_fh(struct net *, struct auth_domain *, struct rpc_clnt *,
46 const struct cred *, const struct nfs_fh *,
47 const fmode_t) __must_hold(rcu);
48
49 struct nfsd_localio_operations {
50 bool (*nfsd_serv_try_get)(struct net *);
51 void (*nfsd_serv_put)(struct net *);
52 struct nfsd_file *(*nfsd_open_local_fh)(struct net *,
53 struct auth_domain *,
54 struct rpc_clnt *,
55 const struct cred *,
56 const struct nfs_fh *,
57 const fmode_t);
58 void (*nfsd_file_put_local)(struct nfsd_file *);
59 struct file *(*nfsd_file_file)(struct nfsd_file *);
60 } ____cacheline_aligned;
61
62 extern void nfsd_localio_ops_init(void);
63 extern const struct nfsd_localio_operations *nfs_to;
64
65 struct nfsd_file *nfs_open_local_fh(nfs_uuid_t *,
66 struct rpc_clnt *, const struct cred *,
67 const struct nfs_fh *, const fmode_t);
68
69 static inline void nfs_to_nfsd_file_put_local(struct nfsd_file *localio)
70 {
71 /*
72 * Once reference to nfsd_serv is dropped, NFSD could be
73 * unloaded, so ensure safe return from nfsd_file_put_local()
74 * by always taking RCU.
75 */
76 rcu_read_lock();
77 nfs_to->nfsd_file_put_local(localio);
78 rcu_read_unlock();
79 }
80
81 #else /* CONFIG_NFS_LOCALIO */
82 static inline void nfsd_localio_ops_init(void)
83 {
84 }
85 static inline void nfs_to_nfsd_file_put_local(struct nfsd_file *localio)
86 {
87 }
88 #endif /* CONFIG_NFS_LOCALIO */
89
90 #endif /* __LINUX_NFSLOCALIO_H */
91
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.