root/net/sunrpc/sysctl.c

DEFINITIONS

1. rpc_register_sysctl
2. rpc_unregister_sysctl
3. proc_do_xprt
4. proc_dodebug

/*
 * linux/net/sunrpc/sysctl.c
 *
 * Sysctl interface to sunrpc module.
 *
 * I would prefer to register the sunrpc table below sys/net, but that's
 * impossible at the moment.
 */

#include <linux/types.h>
#include <linux/linkage.h>
#include <linux/ctype.h>
#include <linux/fs.h>
#include <linux/sysctl.h>
#include <linux/module.h>

#include <asm/uaccess.h>
#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
 */
unsigned int    rpc_debug;
EXPORT_SYMBOL_GPL(rpc_debug);

unsigned int    nfs_debug;
EXPORT_SYMBOL_GPL(nfs_debug);

unsigned int    nfsd_debug;
EXPORT_SYMBOL_GPL(nfsd_debug);

unsigned int    nlm_debug;
EXPORT_SYMBOL_GPL(nlm_debug);

#ifdef RPC_DEBUG

static struct ctl_table_header *sunrpc_table_header;
static ctl_table                sunrpc_table[];

void
rpc_register_sysctl(void)
{
        if (!sunrpc_table_header)
                sunrpc_table_header = register_sysctl_table(sunrpc_table);
}

void
rpc_unregister_sysctl(void)
{
        if (sunrpc_table_header) {
                unregister_sysctl_table(sunrpc_table_header);
                sunrpc_table_header = NULL;
        }
}

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];
        size_t len;

        if ((*ppos && !write) || !*lenp) {
                *lenp = 0;
                return 0;
        }
        len = svc_print_xprts(tmpbuf, sizeof(tmpbuf));
        return simple_read_from_buffer(buffer, *lenp, ppos, tmpbuf, len);
}

static int
proc_dodebug(ctl_table *table, int write, struct file *file,
                                void __user *buffer, size_t *lenp, loff_t *ppos)
{
        char            tmpbuf[20], c, *s;
        char __user *p;
        unsigned int    value;
        size_t          left, len;

        if ((*ppos && !write) || !*lenp) {
                *lenp = 0;
                return 0;
        }

        left = *lenp;

        if (write) {
                if (!access_ok(VERIFY_READ, buffer, left))
                        return -EFAULT;
                p = buffer;
                while (left && __get_user(c, p) >= 0 && isspace(c))
                        left--, p++;
                if (!left)
                        goto done;

                if (left > sizeof(tmpbuf) - 1)
                        return -EINVAL;
                if (copy_from_user(tmpbuf, p, left))
                        return -EFAULT;
                tmpbuf[left] = '\0';

                for (s = tmpbuf, value = 0; '0' <= *s && *s <= '9'; s++, left--)
                        value = 10 * value + (*s - '0');
                if (*s && !isspace(*s))
                        return -EINVAL;
                while (left && isspace(*s))
                        left--, s++;
                *(unsigned int *) table->data = value;
                /* Display the RPC tasks on writing to rpc_debug */
                if (strcmp(table->procname, "rpc_debug") == 0)
                        rpc_show_tasks();
        } else {
                if (!access_ok(VERIFY_WRITE, buffer, left))
                        return -EFAULT;
                len = sprintf(tmpbuf, "%d", *(unsigned int *) table->data);
                if (len > left)
                        len = left;
                if (__copy_to_user(buffer, tmpbuf, len))
                        return -EFAULT;
                if ((left -= len) > 0) {
                        if (put_user('\n', (char __user *)buffer + len))
                                return -EFAULT;
                        left--;
                }
        }

done:
        *lenp -= left;
        *ppos += *lenp;
        return 0;
}


static ctl_table debug_table[] = {
        {
                .procname       = "rpc_debug",
                .data           = &rpc_debug,
                .maxlen         = sizeof(int),
                .mode           = 0644,
                .proc_handler   = &proc_dodebug
        },
        {
                .procname       = "nfs_debug",
                .data           = &nfs_debug,
                .maxlen         = sizeof(int),
                .mode           = 0644,
                .proc_handler   = &proc_dodebug
        },
        {
                .procname       = "nfsd_debug",
                .data           = &nfsd_debug,
                .maxlen         = sizeof(int),
                .mode           = 0644,
                .proc_handler   = &proc_dodebug
        },
        {
                .procname       = "nlm_debug",
                .data           = &nlm_debug,
                .maxlen         = sizeof(int),
                .mode           = 0644,
                .proc_handler   = &proc_dodebug
        },
        {
                .procname       = "transports",
                .maxlen         = 256,
                .mode           = 0444,
                .proc_handler   = &proc_do_xprt,
        },
        { .ctl_name = 0 }
};

static ctl_table sunrpc_table[] = {
        {
                .ctl_name       = CTL_SUNRPC,
                .procname       = "sunrpc",
                .mode           = 0555,
                .child          = debug_table
        },
        { .ctl_name = 0 }
};

#endif