Commit 587bc725 authored by Olga Kornievskaia's avatar Olga Kornievskaia Committed by Trond Myklebust
Browse files

sunrpc: add dst_attr attributes to the sysfs xprt directory 



Allow to query and set the destination's address of a transport.
Setting of the destination address is allowed only for TCP or RDMA
based connections.

Signed-off-by: default avatarOlga Kornievskaia <kolga@netapp.com>
Signed-off-by: default avatarTrond Myklebust <trond.myklebust@hammerspace.com>
parent d408ebe0

include/linux/sunrpc/xprt.h

+1 −0
Original line number Diff line number Diff line
@@ -414,6 +414,7 @@ void xprt_conditional_disconnect(struct rpc_xprt *xprt, unsigned int cookie); 


bool			xprt_lock_connect(struct rpc_xprt *, struct rpc_task *, void *);

void			xprt_unlock_connect(struct rpc_xprt *, void *);

void			xprt_release_write(struct rpc_xprt *, struct rpc_task *);



/*

 * Reserved bit positions in xprt->state

net/sunrpc/sysfs.c

+105 −0
Original line number Diff line number Diff line
@@ -4,8 +4,23 @@ 
 */

#include <linux/sunrpc/clnt.h>

#include <linux/kobject.h>

#include <linux/sunrpc/addr.h>



#include "sysfs.h"



struct xprt_addr {

	const char *addr;

	struct rcu_head rcu;

};



static void free_xprt_addr(struct rcu_head *head)

{

	struct xprt_addr *addr = container_of(head, struct xprt_addr, rcu);



	kfree(addr->addr);

	kfree(addr);

}



static struct kset *rpc_sunrpc_kset;

static struct kobject *rpc_sunrpc_client_kobj, *rpc_sunrpc_xprt_switch_kobj;
@@ -43,6 +58,87 @@ static struct kobject *rpc_sysfs_object_alloc(const char *name, 
	return NULL;

}



static inline struct rpc_xprt *

rpc_sysfs_xprt_kobj_get_xprt(struct kobject *kobj)

{

	struct rpc_sysfs_xprt *x = container_of(kobj,

		struct rpc_sysfs_xprt, kobject);



	return xprt_get(x->xprt);

}



static ssize_t rpc_sysfs_xprt_dstaddr_show(struct kobject *kobj,

					   struct kobj_attribute *attr,

					   char *buf)

{

	struct rpc_xprt *xprt = rpc_sysfs_xprt_kobj_get_xprt(kobj);

	ssize_t ret;



	if (!xprt)

		return 0;

	ret = sprintf(buf, "%s\n", xprt->address_strings[RPC_DISPLAY_ADDR]);

	xprt_put(xprt);

	return ret + 1;

}



static ssize_t rpc_sysfs_xprt_dstaddr_store(struct kobject *kobj,

					    struct kobj_attribute *attr,

					    const char *buf, size_t count)

{

	struct rpc_xprt *xprt = rpc_sysfs_xprt_kobj_get_xprt(kobj);

	struct sockaddr *saddr;

	char *dst_addr;

	int port;

	struct xprt_addr *saved_addr;

	size_t buf_len;



	if (!xprt)

		return 0;

	if (!(xprt->xprt_class->ident == XPRT_TRANSPORT_TCP ||

	      xprt->xprt_class->ident == XPRT_TRANSPORT_RDMA)) {

		xprt_put(xprt);

		return -EOPNOTSUPP;

	}



	if (wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_KILLABLE)) {

		count = -EINTR;

		goto out_put;

	}

	saddr = (struct sockaddr *)&xprt->addr;

	port = rpc_get_port(saddr);



	/* buf_len is the len until the first occurence of either

	 * '\n' or '\0'

	 */

	buf_len = strcspn(buf, "\n");



	dst_addr = kstrndup(buf, buf_len, GFP_KERNEL);

	if (!dst_addr)

		goto out_err;

	saved_addr = kzalloc(sizeof(*saved_addr), GFP_KERNEL);

	if (!saved_addr)

		goto out_err_free;

	saved_addr->addr =

		rcu_dereference_raw(xprt->address_strings[RPC_DISPLAY_ADDR]);

	rcu_assign_pointer(xprt->address_strings[RPC_DISPLAY_ADDR], dst_addr);

	call_rcu(&saved_addr->rcu, free_xprt_addr);

	xprt->addrlen = rpc_pton(xprt->xprt_net, buf, buf_len, saddr,

				 sizeof(*saddr));

	rpc_set_port(saddr, port);



	xprt_force_disconnect(xprt);

out:

	xprt_release_write(xprt, NULL);

out_put:

	xprt_put(xprt);

	return count;

out_err_free:

	kfree(dst_addr);

out_err:

	count = -ENOMEM;

	goto out;

}



int rpc_sysfs_init(void)

{

	rpc_sunrpc_kset = kset_create_and_add("sunrpc", NULL, kernel_kobj);
@@ -106,6 +202,14 @@ static const void *rpc_sysfs_xprt_namespace(struct kobject *kobj) 
			    kobject)->xprt->xprt_net;

}



static struct kobj_attribute rpc_sysfs_xprt_dstaddr = __ATTR(dstaddr,

	0644, rpc_sysfs_xprt_dstaddr_show, rpc_sysfs_xprt_dstaddr_store);



static struct attribute *rpc_sysfs_xprt_attrs[] = {

	&rpc_sysfs_xprt_dstaddr.attr,

	NULL,

};



static struct kobj_type rpc_sysfs_client_type = {

	.release = rpc_sysfs_client_release,

	.sysfs_ops = &kobj_sysfs_ops,
@@ -120,6 +224,7 @@ static struct kobj_type rpc_sysfs_xprt_switch_type = { 


static struct kobj_type rpc_sysfs_xprt_type = {

	.release = rpc_sysfs_xprt_release,

	.default_attrs = rpc_sysfs_xprt_attrs,

	.sysfs_ops = &kobj_sysfs_ops,

	.namespace = rpc_sysfs_xprt_namespace,

};

net/sunrpc/xprt.c

+3 −1
Original line number Diff line number Diff line
@@ -55,6 +55,7 @@ 
#include <trace/events/sunrpc.h>



#include "sunrpc.h"

#include "sysfs.h"



/*

 * Local variables
@@ -443,7 +444,7 @@ void xprt_release_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task) 
}

EXPORT_SYMBOL_GPL(xprt_release_xprt_cong);



static inline void xprt_release_write(struct rpc_xprt *xprt, struct rpc_task *task)

void xprt_release_write(struct rpc_xprt *xprt, struct rpc_task *task)

{

	if (xprt->snd_task != task)

		return;
@@ -1812,6 +1813,7 @@ void xprt_free(struct rpc_xprt *xprt) 
	put_net(xprt->xprt_net);

	xprt_free_all_slots(xprt);

	xprt_free_id(xprt);

	rpc_sysfs_xprt_destroy(xprt);

	kfree_rcu(xprt, rcu);

}

EXPORT_SYMBOL_GPL(xprt_free);

net/sunrpc/xprtmultipath.c

+0 −2
Original line number Diff line number Diff line
@@ -86,7 +86,6 @@ void rpc_xprt_switch_remove_xprt(struct rpc_xprt_switch *xps, 
	spin_lock(&xps->xps_lock);

	xprt_switch_remove_xprt_locked(xps, xprt);

	spin_unlock(&xps->xps_lock);

	rpc_sysfs_xprt_destroy(xprt);

	xprt_put(xprt);

}
@@ -155,7 +154,6 @@ static void xprt_switch_free_entries(struct rpc_xprt_switch *xps) 
				struct rpc_xprt, xprt_switch);

		xprt_switch_remove_xprt_locked(xps, xprt);

		spin_unlock(&xps->xps_lock);

		rpc_sysfs_xprt_destroy(xprt);

		xprt_put(xprt);

		spin_lock(&xps->xps_lock);

	}