linux_dsm_epyc7002/include/linux/lockd/bind.h
Benjamin Coddington b1ece737f4 lockd: Introduce nlmclnt_operations
NFS would enjoy the ability to modify the behavior of the NLM client's
unlock RPC task in order to delay the transmission of the unlock until IO
that was submitted under that lock has completed.  This ability can ensure
that the NLM client will always complete the transmission of an unlock even
if the waiting caller has been interrupted with fatal signal.

For this purpose, a pointer to a struct nlmclnt_operations can be assigned
in a nfs_module's nfs_rpc_ops that will install those nlmclnt_operations on
the nlm_host.  The struct nlmclnt_operations defines three callback
operations that will be used in a following patch:

nlmclnt_alloc_call - used to call back after a successful allocation of
	a struct nlm_rqst in nlmclnt_proc().

nlmclnt_unlock_prepare - used to call back during NLM unlock's
	rpc_call_prepare.  The NLM client defers calling rpc_call_start()
	until this callback returns false.

nlmclnt_release_call - used to call back when the NLM client's struct
	nlm_rqst is freed.

Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-04-21 10:45:01 -04:00

81 lines
2.1 KiB
C

/*
* linux/include/linux/lockd/bind.h
*
* This is the part of lockd visible to nfsd and the nfs client.
*
* Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
*/
#ifndef LINUX_LOCKD_BIND_H
#define LINUX_LOCKD_BIND_H
#include <linux/lockd/nlm.h>
/* need xdr-encoded error codes too, so... */
#include <linux/lockd/xdr.h>
#ifdef CONFIG_LOCKD_V4
#include <linux/lockd/xdr4.h>
#endif
/* Dummy declarations */
struct svc_rqst;
struct rpc_task;
/*
* This is the set of functions for lockd->nfsd communication
*/
struct nlmsvc_binding {
__be32 (*fopen)(struct svc_rqst *,
struct nfs_fh *,
struct file **);
void (*fclose)(struct file *);
};
extern const struct nlmsvc_binding *nlmsvc_ops;
/*
* Similar to nfs_client_initdata, but without the NFS-specific
* rpc_ops field.
*/
struct nlmclnt_initdata {
const char *hostname;
const struct sockaddr *address;
size_t addrlen;
unsigned short protocol;
u32 nfs_version;
int noresvport;
struct net *net;
const struct nlmclnt_operations *nlmclnt_ops;
};
/*
* Functions exported by the lockd module
*/
extern struct nlm_host *nlmclnt_init(const struct nlmclnt_initdata *nlm_init);
extern void nlmclnt_done(struct nlm_host *host);
/*
* NLM client operations provide a means to modify RPC processing of NLM
* requests. Callbacks receive a pointer to data passed into the call to
* nlmclnt_proc().
*/
struct nlmclnt_operations {
/* Called on successful allocation of nlm_rqst, use for allocation or
* reference counting. */
void (*nlmclnt_alloc_call)(void *);
/* Called in rpc_task_prepare for unlock. A return value of true
* indicates the callback has put the task to sleep on a waitqueue
* and NLM should not call rpc_call_start(). */
bool (*nlmclnt_unlock_prepare)(struct rpc_task*, void *);
/* Called when the nlm_rqst is freed, callbacks should clean up here */
void (*nlmclnt_release_call)(void *);
};
extern int nlmclnt_proc(struct nlm_host *host, int cmd, struct file_lock *fl, void *data);
extern int lockd_up(struct net *net);
extern void lockd_down(struct net *net);
#endif /* LINUX_LOCKD_BIND_H */