1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * Copyright (C) 2024 Mike Snitzer <[email protected]> 4 * Copyright (C) 2024 NeilBrown <[email protected]> 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_begin(nfs_uuid_t *); 36 void nfs_uuid_end(nfs_uuid_t *); 37 void nfs_uuid_is_local(const uuid_t *, struct list_head *, 38 struct net *, struct auth_domain *, struct module *); 39 void nfs_uuid_invalidate_clients(struct list_head *list); 40 void nfs_uuid_invalidate_one_client(nfs_uuid_t *nfs_uuid); 41 42 /* localio needs to map filehandle -> struct nfsd_file */ 43 extern struct nfsd_file * 44 nfsd_open_local_fh(struct net *, struct auth_domain *, struct rpc_clnt *, 45 const struct cred *, const struct nfs_fh *, 46 const fmode_t) __must_hold(rcu); 47 48 struct nfsd_localio_operations { 49 bool (*nfsd_serv_try_get)(struct net *); 50 void (*nfsd_serv_put)(struct net *); 51 struct nfsd_file *(*nfsd_open_local_fh)(struct net *, 52 struct auth_domain *, 53 struct rpc_clnt *, 54 const struct cred *, 55 const struct nfs_fh *, 56 const fmode_t); 57 void (*nfsd_file_put_local)(struct nfsd_file *); 58 struct file *(*nfsd_file_file)(struct nfsd_file *); 59 } ____cacheline_aligned; 60 61 extern void nfsd_localio_ops_init(void); 62 extern const struct nfsd_localio_operations *nfs_to; 63 64 struct nfsd_file *nfs_open_local_fh(nfs_uuid_t *, 65 struct rpc_clnt *, const struct cred *, 66 const struct nfs_fh *, const fmode_t); 67 68 static inline void nfs_to_nfsd_file_put_local(struct nfsd_file *localio) 69 { 70 /* 71 * Once reference to nfsd_serv is dropped, NFSD could be 72 * unloaded, so ensure safe return from nfsd_file_put_local() 73 * by always taking RCU. 74 */ 75 rcu_read_lock(); 76 nfs_to->nfsd_file_put_local(localio); 77 rcu_read_unlock(); 78 } 79 80 #else /* CONFIG_NFS_LOCALIO */ 81 static inline void nfsd_localio_ops_init(void) 82 { 83 } 84 static inline void nfs_to_nfsd_file_put_local(struct nfsd_file *localio) 85 { 86 } 87 #endif /* CONFIG_NFS_LOCALIO */ 88 89 #endif /* __LINUX_NFSLOCALIO_H */ 90