svc: Add /proc/sys/sunrpc/transport files
Add a file that when read lists the set of registered svc
transports.
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/net/sunrpc/svc_xprt.c b/net/sunrpc/svc_xprt.c
index 000c7dc..2e5b92a 100644
--- a/net/sunrpc/svc_xprt.c
+++ b/net/sunrpc/svc_xprt.c
@@ -112,6 +112,34 @@
}
EXPORT_SYMBOL_GPL(svc_unreg_xprt_class);
+/*
+ * Format the transport list for printing
+ */
+int svc_print_xprts(char *buf, int maxlen)
+{
+ struct list_head *le;
+ char tmpstr[80];
+ int len = 0;
+ buf[0] = '\0';
+
+ spin_lock(&svc_xprt_class_lock);
+ list_for_each(le, &svc_xprt_class_list) {
+ int slen;
+ struct svc_xprt_class *xcl =
+ list_entry(le, struct svc_xprt_class, xcl_list);
+
+ sprintf(tmpstr, "%s %d\n", xcl->xcl_name, xcl->xcl_max_payload);
+ slen = strlen(tmpstr);
+ if (len + slen > maxlen)
+ break;
+ len += slen;
+ strcat(buf, tmpstr);
+ }
+ spin_unlock(&svc_xprt_class_lock);
+
+ return len;
+}
+
static void svc_xprt_free(struct kref *kref)
{
struct svc_xprt *xprt =
diff --git a/net/sunrpc/sysctl.c b/net/sunrpc/sysctl.c
index bada7de..0f8c439 100644
--- a/net/sunrpc/sysctl.c
+++ b/net/sunrpc/sysctl.c
@@ -18,6 +18,7 @@
#include <linux/sunrpc/types.h>
#include <linux/sunrpc/sched.h>
#include <linux/sunrpc/stats.h>
+#include <linux/sunrpc/svc_xprt.h>
/*
* Declare the debug flags here
@@ -55,6 +56,30 @@
}
}
+static int proc_do_xprt(ctl_table *table, int write, struct file *file,
+ void __user *buffer, size_t *lenp, loff_t *ppos)
+{
+ char tmpbuf[256];
+ int len;
+ if ((*ppos && !write) || !*lenp) {
+ *lenp = 0;
+ return 0;
+ }
+ if (write)
+ return -EINVAL;
+ else {
+ len = svc_print_xprts(tmpbuf, sizeof(tmpbuf));
+ if (!access_ok(VERIFY_WRITE, buffer, len))
+ return -EFAULT;
+
+ if (__copy_to_user(buffer, tmpbuf, len))
+ return -EFAULT;
+ }
+ *lenp -= len;
+ *ppos += len;
+ return 0;
+}
+
static int
proc_dodebug(ctl_table *table, int write, struct file *file,
void __user *buffer, size_t *lenp, loff_t *ppos)
@@ -147,6 +172,12 @@
.mode = 0644,
.proc_handler = &proc_dodebug
},
+ {
+ .procname = "transports",
+ .maxlen = 256,
+ .mode = 0444,
+ .proc_handler = &proc_do_xprt,
+ },
{ .ctl_name = 0 }
};