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: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
This commit is contained in:
Olga Kornievskaia 2021-06-08 15:59:19 -04:00 committed by Trond Myklebust
parent d408ebe04a
commit 587bc7255d
4 changed files with 109 additions and 3 deletions

View File

@ -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

View File

@ -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,
};

View File

@ -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);

View File

@ -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);
}