SUNRPC: Add a helper to apply a function to all the rpc_clnt's transports

Add a helper for tasks that require us to apply a function to all the
transports in an rpc_clnt.
An example of a usecase would be BIND_CONN_TO_SESSION, where we want
to send one RPC call down each transport.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
This commit is contained in:
Trond Myklebust 2016-01-30 20:39:19 -05:00
parent 9d61498d5f
commit 3227886c65
2 changed files with 55 additions and 0 deletions

View File

@ -182,6 +182,10 @@ size_t rpc_peeraddr(struct rpc_clnt *, struct sockaddr *, size_t);
const char *rpc_peeraddr2str(struct rpc_clnt *, enum rpc_display_format_t);
int rpc_localaddr(struct rpc_clnt *, struct sockaddr *, size_t);
int rpc_clnt_iterate_for_each_xprt(struct rpc_clnt *clnt,
int (*fn)(struct rpc_clnt *, struct rpc_xprt *, void *),
void *data);
const char *rpc_proc_name(const struct rpc_task *task);
#endif /* __KERNEL__ */
#endif /* _LINUX_SUNRPC_CLNT_H */

View File

@ -736,6 +736,57 @@ out_revert:
}
EXPORT_SYMBOL_GPL(rpc_switch_client_transport);
static
int rpc_clnt_xprt_iter_init(struct rpc_clnt *clnt, struct rpc_xprt_iter *xpi)
{
struct rpc_xprt_switch *xps;
rcu_read_lock();
xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
rcu_read_unlock();
if (xps == NULL)
return -EAGAIN;
xprt_iter_init_listall(xpi, xps);
xprt_switch_put(xps);
return 0;
}
/**
* rpc_clnt_iterate_for_each_xprt - Apply a function to all transports
* @clnt: pointer to client
* @fn: function to apply
* @data: void pointer to function data
*
* Iterates through the list of RPC transports currently attached to the
* client and applies the function fn(clnt, xprt, data).
*
* On error, the iteration stops, and the function returns the error value.
*/
int rpc_clnt_iterate_for_each_xprt(struct rpc_clnt *clnt,
int (*fn)(struct rpc_clnt *, struct rpc_xprt *, void *),
void *data)
{
struct rpc_xprt_iter xpi;
int ret;
ret = rpc_clnt_xprt_iter_init(clnt, &xpi);
if (ret)
return ret;
for (;;) {
struct rpc_xprt *xprt = xprt_iter_get_next(&xpi);
if (!xprt)
break;
ret = fn(clnt, xprt, data);
xprt_put(xprt);
if (ret < 0)
break;
}
xprt_iter_destroy(&xpi);
return ret;
}
EXPORT_SYMBOL_GPL(rpc_clnt_iterate_for_each_xprt);
/*
* Kill all tasks for the given client.
* XXX: kill their descendants as well?