123 lines
		
	
	
		
			3.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			123 lines
		
	
	
		
			3.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* SPDX-License-Identifier: GPL-2.0 */
 | |
| /*
 | |
|  * Copyright (C) 2024 Mike Snitzer <snitzer@hammerspace.com>
 | |
|  * Copyright (C) 2024 NeilBrown <neilb@suse.de>
 | |
|  */
 | |
| #ifndef __LINUX_NFSLOCALIO_H
 | |
| #define __LINUX_NFSLOCALIO_H
 | |
| 
 | |
| #if IS_ENABLED(CONFIG_NFS_LOCALIO)
 | |
| 
 | |
| #include <linux/module.h>
 | |
| #include <linux/list.h>
 | |
| #include <linux/uuid.h>
 | |
| #include <linux/sunrpc/clnt.h>
 | |
| #include <linux/sunrpc/svcauth.h>
 | |
| #include <linux/nfs.h>
 | |
| #include <net/net_namespace.h>
 | |
| 
 | |
| struct nfs_client;
 | |
| struct nfs_file_localio;
 | |
| 
 | |
| /*
 | |
|  * Useful to allow a client to negotiate if localio
 | |
|  * possible with its server.
 | |
|  *
 | |
|  * See Documentation/filesystems/nfs/localio.rst for more detail.
 | |
|  */
 | |
| typedef struct {
 | |
| 	uuid_t uuid;
 | |
| 	unsigned nfs3_localio_probe_count;
 | |
| 	/* this struct is over a cacheline, avoid bouncing */
 | |
| 	spinlock_t ____cacheline_aligned lock;
 | |
| 	struct list_head list;
 | |
| 	spinlock_t *list_lock; /* nn->local_clients_lock */
 | |
| 	struct net __rcu *net; /* nfsd's network namespace */
 | |
| 	struct auth_domain *dom; /* auth_domain for localio */
 | |
| 	/* Local files to close when net is shut down or exports change */
 | |
| 	struct list_head files;
 | |
| } nfs_uuid_t;
 | |
| 
 | |
| void nfs_uuid_init(nfs_uuid_t *);
 | |
| bool nfs_uuid_begin(nfs_uuid_t *);
 | |
| void nfs_uuid_end(nfs_uuid_t *);
 | |
| void nfs_uuid_is_local(const uuid_t *, struct list_head *, spinlock_t *,
 | |
| 		       struct net *, struct auth_domain *, struct module *);
 | |
| 
 | |
| void nfs_localio_enable_client(struct nfs_client *clp);
 | |
| void nfs_localio_disable_client(struct nfs_client *clp);
 | |
| void nfs_localio_invalidate_clients(struct list_head *nn_local_clients,
 | |
| 				    spinlock_t *nn_local_clients_lock);
 | |
| 
 | |
| /* localio needs to map filehandle -> struct nfsd_file */
 | |
| extern struct nfsd_file *
 | |
| nfsd_open_local_fh(struct net *, struct auth_domain *, struct rpc_clnt *,
 | |
| 		   const struct cred *, const struct nfs_fh *,
 | |
| 		   const fmode_t) __must_hold(rcu);
 | |
| void nfs_close_local_fh(struct nfs_file_localio *);
 | |
| 
 | |
| struct nfsd_localio_operations {
 | |
| 	bool (*nfsd_net_try_get)(struct net *);
 | |
| 	void (*nfsd_net_put)(struct net *);
 | |
| 	struct nfsd_file *(*nfsd_open_local_fh)(struct net *,
 | |
| 						struct auth_domain *,
 | |
| 						struct rpc_clnt *,
 | |
| 						const struct cred *,
 | |
| 						const struct nfs_fh *,
 | |
| 						const fmode_t);
 | |
| 	struct net *(*nfsd_file_put_local)(struct nfsd_file *);
 | |
| 	struct nfsd_file *(*nfsd_file_get)(struct nfsd_file *);
 | |
| 	void (*nfsd_file_put)(struct nfsd_file *);
 | |
| 	struct file *(*nfsd_file_file)(struct nfsd_file *);
 | |
| } ____cacheline_aligned;
 | |
| 
 | |
| extern void nfsd_localio_ops_init(void);
 | |
| extern const struct nfsd_localio_operations *nfs_to;
 | |
| 
 | |
| struct nfsd_file *nfs_open_local_fh(nfs_uuid_t *,
 | |
| 		   struct rpc_clnt *, const struct cred *,
 | |
| 		   const struct nfs_fh *, struct nfs_file_localio *,
 | |
| 		   const fmode_t);
 | |
| 
 | |
| static inline void nfs_to_nfsd_net_put(struct net *net)
 | |
| {
 | |
| 	/*
 | |
| 	 * Once reference to net (and associated nfsd_serv) is dropped, NFSD
 | |
| 	 * could be unloaded, so ensure safe return from nfsd_net_put() by
 | |
| 	 * always taking RCU.
 | |
| 	 */
 | |
| 	rcu_read_lock();
 | |
| 	nfs_to->nfsd_net_put(net);
 | |
| 	rcu_read_unlock();
 | |
| }
 | |
| 
 | |
| static inline void nfs_to_nfsd_file_put_local(struct nfsd_file *localio)
 | |
| {
 | |
| 	/*
 | |
| 	 * Must not hold RCU otherwise nfsd_file_put() can easily trigger:
 | |
| 	 * "Voluntary context switch within RCU read-side critical section!"
 | |
| 	 * by scheduling deep in underlying filesystem (e.g. XFS).
 | |
| 	 */
 | |
| 	struct net *net = nfs_to->nfsd_file_put_local(localio);
 | |
| 
 | |
| 	nfs_to_nfsd_net_put(net);
 | |
| }
 | |
| 
 | |
| #else   /* CONFIG_NFS_LOCALIO */
 | |
| 
 | |
| struct nfs_file_localio;
 | |
| static inline void nfs_close_local_fh(struct nfs_file_localio *nfl)
 | |
| {
 | |
| }
 | |
| static inline void nfsd_localio_ops_init(void)
 | |
| {
 | |
| }
 | |
| struct nfs_client;
 | |
| static inline void nfs_localio_disable_client(struct nfs_client *clp)
 | |
| {
 | |
| }
 | |
| 
 | |
| #endif  /* CONFIG_NFS_LOCALIO */
 | |
| 
 | |
| #endif  /* __LINUX_NFSLOCALIO_H */
 |