net/sunrpc/sysctl.c

   1 /*
   2  * linux/net/sunrpc/sysctl.c
   3  *
   4  * Sysctl interface to sunrpc module. This is for debugging only now.
   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/config.h>
  11 #include <linux/version.h>
  12 #include <linux/types.h>
  13 #include <linux/linkage.h>
  14 #include <linux/ctype.h>
  15 #include <linux/fs.h>
  16 #include <linux/sysctl.h>
  17 #define __NO_VERSION__
  18 #include <linux/module.h>
  19
  20 #include <asm/uaccess.h>
  21 #include <linux/sunrpc/types.h>
  22 #include <linux/sunrpc/sched.h>
  23 #include <linux/sunrpc/stats.h>
  24
  25 /*
  26  * Declare the debug flags here
  27  */
  28 unsigned int    rpc_debug;
  29 unsigned int    nfs_debug;
  30 unsigned int    nfsd_debug;
  31 unsigned int    nlm_debug;
  32
  33 #ifdef RPC_DEBUG
  34
  35 static struct ctl_table_header *sunrpc_table_header;
  36 static ctl_table                sunrpc_table[];
  37
  38 void
  39 rpc_register_sysctl(void)
  40 {
  41         if (!sunrpc_table_header) {
  42                 sunrpc_table_header = register_sysctl_table(sunrpc_table, 1);
  43 #ifdef CONFIG_PROC_FS
  44                 if (sunrpc_table[0].de)
  45                         sunrpc_table[0].de->owner = THIS_MODULE;
  46 #endif
  47         }
  48
  49 }
  50
  51 void
  52 rpc_unregister_sysctl(void)
  53 {
  54         if (sunrpc_table_header) {
  55                 unregister_sysctl_table(sunrpc_table_header);
  56                 sunrpc_table_header = NULL;
  57         }
  58 }
  59
  60 static int
  61 proc_dodebug(ctl_table *table, int write, struct file *file,
  62                                 void *buffer, size_t *lenp)
  63 {
  64         char            tmpbuf[20], *p, c;
  65         unsigned int    value;
  66         size_t          left, len;
  67
  68         if ((file->f_pos && !write) || !*lenp) {
  69                 *lenp = 0;
  70                 return 0;
  71         }
  72
  73         left = *lenp;
  74
  75         if (write) {
  76                 if (!access_ok(VERIFY_READ, buffer, left))
  77                         return -EFAULT;
  78                 p = (char *) buffer;
  79                 while (left && __get_user(c, p) >= 0 && isspace(c))
  80                         left--, p++;
  81                 if (!left)
  82                         goto done;
  83
  84                 if (left > sizeof(tmpbuf) - 1)
  85                         return -EINVAL;
  86                 copy_from_user(tmpbuf, p, left);
  87                 tmpbuf[left] = '\0';
  88
  89                 for (p = tmpbuf, value = 0; '0' <= *p && *p <= '9'; p++, left--)
  90                         value = 10 * value + (*p - '0');
  91                 if (*p && !isspace(*p))
  92                         return -EINVAL;
  93                 while (left && isspace(*p))
  94                         left--, p++;
  95                 *(unsigned int *) table->data = value;
  96                 /* Display the RPC tasks on writing to rpc_debug */
  97                 if (table->ctl_name == CTL_RPCDEBUG) {
  98                         rpc_show_tasks();
  99                 }
 100         } else {
 101                 if (!access_ok(VERIFY_WRITE, buffer, left))
 102                         return -EFAULT;
 103                 len = sprintf(tmpbuf, "%d", *(unsigned int *) table->data);
 104                 if (len > left)
 105                         len = left;
 106                 copy_to_user(buffer, tmpbuf, len);
 107                 if ((left -= len) > 0) {
 108                         put_user('\n', (char *)buffer + len);
 109                         left--;
 110                 }
 111         }
 112
 113 done:
 114         *lenp -= left;
 115         file->f_pos += *lenp;
 116         return 0;
 117 }
 118
 119 #define DIRENTRY(nam1, nam2, child)     \
 120         {CTL_##nam1, #nam2, NULL, 0, 0555, child }
 121 #define DBGENTRY(nam1, nam2)    \
 122         {CTL_##nam1##DEBUG, #nam2 "_debug", &nam2##_debug, sizeof(int),\
 123          0644, NULL, &proc_dodebug}
 124
 125 static ctl_table                debug_table[] = {
 126         DBGENTRY(RPC,  rpc),
 127         DBGENTRY(NFS,  nfs),
 128         DBGENTRY(NFSD, nfsd),
 129         DBGENTRY(NLM,  nlm),
 130         {0}
 131 };
 132
 133 static ctl_table                sunrpc_table[] = {
 134         DIRENTRY(SUNRPC, sunrpc, debug_table),
 135         {0}
 136 };
 137
 138 #endif