net/sunrpc/sysctl.c

   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
  22 /*
  23  * Declare the debug flags here
  24  */
  25 unsigned int    rpc_debug;
  26 EXPORT_SYMBOL_GPL(rpc_debug);
  27
  28 unsigned int    nfs_debug;
  29 EXPORT_SYMBOL_GPL(nfs_debug);
  30
  31 unsigned int    nfsd_debug;
  32 EXPORT_SYMBOL_GPL(nfsd_debug);
  33
  34 unsigned int    nlm_debug;
  35 EXPORT_SYMBOL_GPL(nlm_debug);
  36
  37 #ifdef RPC_DEBUG
  38
  39 static struct ctl_table_header *sunrpc_table_header;
  40 static ctl_table                sunrpc_table[];
  41
  42 void
  43 rpc_register_sysctl(void)
  44 {
  45         if (!sunrpc_table_header)
  46                 sunrpc_table_header = register_sysctl_table(sunrpc_table);
  47 }
  48
  49 void
  50 rpc_unregister_sysctl(void)
  51 {
  52         if (sunrpc_table_header) {
  53                 unregister_sysctl_table(sunrpc_table_header);
  54                 sunrpc_table_header = NULL;
  55         }
  56 }
  57
  58 static int
  59 proc_dodebug(ctl_table *table, int write, struct file *file,
  60                                 void __user *buffer, size_t *lenp, loff_t *ppos)
  61 {
  62         char            tmpbuf[20], c, *s;
  63         char __user *p;
  64         unsigned int    value;
  65         size_t          left, len;
  66
  67         if ((*ppos && !write) || !*lenp) {
  68                 *lenp = 0;
  69                 return 0;
  70         }
  71
  72         left = *lenp;
  73
  74         if (write) {
  75                 if (!access_ok(VERIFY_READ, buffer, left))
  76                         return -EFAULT;
  77                 p = buffer;
  78                 while (left && __get_user(c, p) >= 0 && isspace(c))
  79                         left--, p++;
  80                 if (!left)
  81                         goto done;
  82
  83                 if (left > sizeof(tmpbuf) - 1)
  84                         return -EINVAL;
  85                 if (copy_from_user(tmpbuf, p, left))
  86                         return -EFAULT;
  87                 tmpbuf[left] = '\0';
  88
  89                 for (s = tmpbuf, value = 0; '0' <= *s && *s <= '9'; s++, left--)
  90                         value = 10 * value + (*s - '0');
  91                 if (*s && !isspace(*s))
  92                         return -EINVAL;
  93                 while (left && isspace(*s))
  94                         left--, s++;
  95                 *(unsigned int *) table->data = value;
  96                 /* Display the RPC tasks on writing to rpc_debug */
  97                 if (strcmp(table->procname, "rpc_debug") == 0)
  98                         rpc_show_tasks();
  99         } else {
 100                 if (!access_ok(VERIFY_WRITE, buffer, left))
 101                         return -EFAULT;
 102                 len = sprintf(tmpbuf, "%d", *(unsigned int *) table->data);
 103                 if (len > left)
 104                         len = left;
 105                 if (__copy_to_user(buffer, tmpbuf, len))
 106                         return -EFAULT;
 107                 if ((left -= len) > 0) {
 108                         if (put_user('\n', (char __user *)buffer + len))
 109                                 return -EFAULT;
 110                         left--;
 111                 }
 112         }
 113
 114 done:
 115         *lenp -= left;
 116         *ppos += *lenp;
 117         return 0;
 118 }
 119
 120
 121 static ctl_table debug_table[] = {
 122         {
 123                 .procname       = "rpc_debug",
 124                 .data           = &rpc_debug,
 125                 .maxlen         = sizeof(int),
 126                 .mode           = 0644,
 127                 .proc_handler   = &proc_dodebug
 128         },
 129         {
 130                 .procname       = "nfs_debug",
 131                 .data           = &nfs_debug,
 132                 .maxlen         = sizeof(int),
 133                 .mode           = 0644,
 134                 .proc_handler   = &proc_dodebug
 135         },
 136         {
 137                 .procname       = "nfsd_debug",
 138                 .data           = &nfsd_debug,
 139                 .maxlen         = sizeof(int),
 140                 .mode           = 0644,
 141                 .proc_handler   = &proc_dodebug
 142         },
 143         {
 144                 .procname       = "nlm_debug",
 145                 .data           = &nlm_debug,
 146                 .maxlen         = sizeof(int),
 147                 .mode           = 0644,
 148                 .proc_handler   = &proc_dodebug
 149         },
 150         { .ctl_name = 0 }
 151 };
 152
 153 static ctl_table sunrpc_table[] = {
 154         {
 155                 .ctl_name       = CTL_SUNRPC,
 156                 .procname       = "sunrpc",
 157                 .mode           = 0555,
 158                 .child          = debug_table
 159         },
 160         { .ctl_name = 0 }
 161 };
 162
 163 #endif