1/*
  2 * linux/net/sunrpc/sysctl.c
  3 *
  4 * Sysctl interface to sunrpc module.
  5 *
  6 * I would prefer to register the sunrpc table below sys/net, but that's
  7 * impossible at the moment.
  8 */
  9
 10#include <linux/types.h>
 11#include <linux/linkage.h>
 12#include <linux/ctype.h>
 13#include <linux/fs.h>
 14#include <linux/sysctl.h>
 15#include <linux/module.h>
 16
 17#include <asm/uaccess.h>
 18#include <linux/sunrpc/types.h>
 19#include <linux/sunrpc/sched.h>
 20#include <linux/sunrpc/stats.h>
 21#include <linux/sunrpc/svc_xprt.h>
 22
 23#include "netns.h"
 24
 25/*
 26 * Declare the debug flags here
 27 */
 28unsigned int	rpc_debug;
 29EXPORT_SYMBOL_GPL(rpc_debug);
 30
 31unsigned int	nfs_debug;
 32EXPORT_SYMBOL_GPL(nfs_debug);
 33
 34unsigned int	nfsd_debug;
 35EXPORT_SYMBOL_GPL(nfsd_debug);
 36
 37unsigned int	nlm_debug;
 38EXPORT_SYMBOL_GPL(nlm_debug);
 39
 40#ifdef RPC_DEBUG
 41
 42static struct ctl_table_header *sunrpc_table_header;
 43static ctl_table		sunrpc_table[];
 44
 45void
 46rpc_register_sysctl(void)
 47{
 48	if (!sunrpc_table_header)
 49		sunrpc_table_header = register_sysctl_table(sunrpc_table);
 50}
 51
 52void
 53rpc_unregister_sysctl(void)
 54{
 55	if (sunrpc_table_header) {
 56		unregister_sysctl_table(sunrpc_table_header);
 57		sunrpc_table_header = NULL;
 58	}
 59}
 60
 61static int proc_do_xprt(ctl_table *table, int write,
 62			void __user *buffer, size_t *lenp, loff_t *ppos)
 63{
 64	char tmpbuf[256];
 65	size_t len;
 66
 67	if ((*ppos && !write) || !*lenp) {
 68		*lenp = 0;
 69		return 0;
 70	}
 71	len = svc_print_xprts(tmpbuf, sizeof(tmpbuf));
 72	return simple_read_from_buffer(buffer, *lenp, ppos, tmpbuf, len);
 73}
 74
 75static int
 76proc_dodebug(ctl_table *table, int write,
 77				void __user *buffer, size_t *lenp, loff_t *ppos)
 78{
 79	char		tmpbuf[20], c, *s;
 80	char __user *p;
 81	unsigned int	value;
 82	size_t		left, len;
 83
 84	if ((*ppos && !write) || !*lenp) {
 85		*lenp = 0;
 86		return 0;
 87	}
 88
 89	left = *lenp;
 90
 91	if (write) {
 92		if (!access_ok(VERIFY_READ, buffer, left))
 93			return -EFAULT;
 94		p = buffer;
 95		while (left && __get_user(c, p) >= 0 && isspace(c))
 96			left--, p++;
 97		if (!left)
 98			goto done;
 99
100		if (left > sizeof(tmpbuf) - 1)
101			return -EINVAL;
102		if (copy_from_user(tmpbuf, p, left))
103			return -EFAULT;
104		tmpbuf[left] = '\0';
105
106		for (s = tmpbuf, value = 0; '0' <= *s && *s <= '9'; s++, left--)
107			value = 10 * value + (*s - '0');
108		if (*s && !isspace(*s))
109			return -EINVAL;
110		while (left && isspace(*s))
111			left--, s++;
112		*(unsigned int *) table->data = value;
113		/* Display the RPC tasks on writing to rpc_debug */
114		if (strcmp(table->procname, "rpc_debug") == 0)
115			rpc_show_tasks(&init_net);
116	} else {
117		if (!access_ok(VERIFY_WRITE, buffer, left))
118			return -EFAULT;
119		len = sprintf(tmpbuf, "%d", *(unsigned int *) table->data);
120		if (len > left)
121			len = left;
122		if (__copy_to_user(buffer, tmpbuf, len))
123			return -EFAULT;
124		if ((left -= len) > 0) {
125			if (put_user('\n', (char __user *)buffer + len))
126				return -EFAULT;
127			left--;
128		}
129	}
130
131done:
132	*lenp -= left;
133	*ppos += *lenp;
134	return 0;
135}
136
137
138static ctl_table debug_table[] = {
139	{
140		.procname	= "rpc_debug",
141		.data		= &rpc_debug,
142		.maxlen		= sizeof(int),
143		.mode		= 0644,
144		.proc_handler	= proc_dodebug
145	},
146	{
147		.procname	= "nfs_debug",
148		.data		= &nfs_debug,
149		.maxlen		= sizeof(int),
150		.mode		= 0644,
151		.proc_handler	= proc_dodebug
152	},
153	{
154		.procname	= "nfsd_debug",
155		.data		= &nfsd_debug,
156		.maxlen		= sizeof(int),
157		.mode		= 0644,
158		.proc_handler	= proc_dodebug
159	},
160	{
161		.procname	= "nlm_debug",
162		.data		= &nlm_debug,
163		.maxlen		= sizeof(int),
164		.mode		= 0644,
165		.proc_handler	= proc_dodebug
166	},
167	{
168		.procname	= "transports",
169		.maxlen		= 256,
170		.mode		= 0444,
171		.proc_handler	= proc_do_xprt,
172	},
173	{ }
174};
175
176static ctl_table sunrpc_table[] = {
177	{
178		.procname	= "sunrpc",
179		.mode		= 0555,
180		.child		= debug_table
181	},
182	{ }
183};
184
185#endif