knfsd: Support adding transports by writing portlist file
Update the write handler for the portlist file to allow creating new
listening endpoints on a transport. The general form of the string is:
<transport_name><space><port number>
For example:
echo "tcp 2049" > /proc/fs/nfsd/portlist
This is intended to support the creation of a listening endpoint for
RDMA transports without adding #ifdef code to the nfssvc.c file.
Transports can also be removed as follows:
'-'<transport_name><space><port number>
For example:
echo "-tcp 2049" > /proc/fs/nfsd/portlist
Attempting to add a listener with an invalid transport string results
in EPROTONOSUPPORT and a perror string of "Protocol not supported".
Attempting to remove an non-existent listener (.e.g. bad proto or port)
results in ENOTCONN and a perror string of
"Transport endpoint is not connected"
Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
Acked-by: Neil Brown <neilb@suse.de>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Greg Banks <gnb@sgi.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
diff --git a/fs/nfsd/nfsctl.c b/fs/nfsd/nfsctl.c
index 4aba926..eff6a6b 100644
--- a/fs/nfsd/nfsctl.c
+++ b/fs/nfsd/nfsctl.c
@@ -540,7 +540,7 @@
}
return err < 0 ? err : 0;
}
- if (buf[0] == '-') {
+ if (buf[0] == '-' && isdigit(buf[1])) {
char *toclose = kstrdup(buf+1, GFP_KERNEL);
int len = 0;
if (!toclose)
@@ -554,6 +554,53 @@
kfree(toclose);
return len;
}
+ /*
+ * Add a transport listener by writing it's transport name
+ */
+ if (isalpha(buf[0])) {
+ int err;
+ char transport[16];
+ int port;
+ if (sscanf(buf, "%15s %4d", transport, &port) == 2) {
+ err = nfsd_create_serv();
+ if (!err) {
+ err = svc_create_xprt(nfsd_serv,
+ transport, port,
+ SVC_SOCK_ANONYMOUS);
+ if (err == -ENOENT)
+ /* Give a reasonable perror msg for
+ * bad transport string */
+ err = -EPROTONOSUPPORT;
+ }
+ return err < 0 ? err : 0;
+ }
+ }
+ /*
+ * Remove a transport by writing it's transport name and port number
+ */
+ if (buf[0] == '-' && isalpha(buf[1])) {
+ struct svc_xprt *xprt;
+ int err = -EINVAL;
+ char transport[16];
+ int port;
+ if (sscanf(&buf[1], "%15s %4d", transport, &port) == 2) {
+ if (port == 0)
+ return -EINVAL;
+ lock_kernel();
+ if (nfsd_serv) {
+ xprt = svc_find_xprt(nfsd_serv, transport,
+ AF_UNSPEC, port);
+ if (xprt) {
+ svc_close_xprt(xprt);
+ svc_xprt_put(xprt);
+ err = 0;
+ } else
+ err = -ENOTCONN;
+ }
+ unlock_kernel();
+ return err < 0 ? err : 0;
+ }
+ }
return -EINVAL;
}