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 <linux/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  */
  28 unsigned int    rpc_debug;
  29 EXPORT_SYMBOL_GPL(rpc_debug);
  30
  31 unsigned int    nfs_debug;
  32 EXPORT_SYMBOL_GPL(nfs_debug);
  33
  34 unsigned int    nfsd_debug;
  35 EXPORT_SYMBOL_GPL(nfsd_debug);
  36
  37 unsigned int    nlm_debug;
  38 EXPORT_SYMBOL_GPL(nlm_debug);
  39
  40 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
  41
  42 static struct ctl_table_header *sunrpc_table_header;
  43 static struct ctl_table sunrpc_table[];
  44
  45 void
  46 rpc_register_sysctl(void)
  47 {
  48         if (!sunrpc_table_header)
  49                 sunrpc_table_header = register_sysctl_table(sunrpc_table);
  50 }
  51
  52 void
  53 rpc_unregister_sysctl(void)
  54 {
  55         if (sunrpc_table_header) {
  56                 unregister_sysctl_table(sunrpc_table_header);
  57                 sunrpc_table_header = NULL;
  58         }
  59 }
  60
  61 static int proc_do_xprt(struct 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
  75 static int
  76 proc_dodebug(struct ctl_table *table, int write,
  77                                 void __user *buffer, size_t *lenp, loff_t *ppos)
  78 {
  79         char            tmpbuf[20], c, *s = NULL;
  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(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                 value = simple_strtol(tmpbuf, &s, 0);
 107                 if (s) {
 108                         left -= (s - tmpbuf);
 109                         if (left && !isspace(*s))
 110                                 return -EINVAL;
 111                         while (left && isspace(*s))
 112                                 left--, s++;
 113                 } else
 114                         left = 0;
 115                 *(unsigned int *) table->data = value;
 116                 /* Display the RPC tasks on writing to rpc_debug */
 117                 if (strcmp(table->procname, "rpc_debug") == 0)
 118                         rpc_show_tasks(&init_net);
 119         } else {
 120                 len = sprintf(tmpbuf, "0x%04x", *(unsigned int *) table->data);
 121                 if (len > left)
 122                         len = left;
 123                 if (copy_to_user(buffer, tmpbuf, len))
 124                         return -EFAULT;
 125                 if ((left -= len) > 0) {
 126                         if (put_user('\n', (char __user *)buffer + len))
 127                                 return -EFAULT;
 128                         left--;
 129                 }
 130         }
 131
 132 done:
 133         *lenp -= left;
 134         *ppos += *lenp;
 135         return 0;
 136 }
 137
 138
 139 static struct ctl_table debug_table[] = {
 140         {
 141                 .procname       = "rpc_debug",
 142                 .data           = &rpc_debug,
 143                 .maxlen         = sizeof(int),
 144                 .mode           = 0644,
 145                 .proc_handler   = proc_dodebug
 146         },
 147         {
 148                 .procname       = "nfs_debug",
 149                 .data           = &nfs_debug,
 150                 .maxlen         = sizeof(int),
 151                 .mode           = 0644,
 152                 .proc_handler   = proc_dodebug
 153         },
 154         {
 155                 .procname       = "nfsd_debug",
 156                 .data           = &nfsd_debug,
 157                 .maxlen         = sizeof(int),
 158                 .mode           = 0644,
 159                 .proc_handler   = proc_dodebug
 160         },
 161         {
 162                 .procname       = "nlm_debug",
 163                 .data           = &nlm_debug,
 164                 .maxlen         = sizeof(int),
 165                 .mode           = 0644,
 166                 .proc_handler   = proc_dodebug
 167         },
 168         {
 169                 .procname       = "transports",
 170                 .maxlen         = 256,
 171                 .mode           = 0444,
 172                 .proc_handler   = proc_do_xprt,
 173         },
 174         { }
 175 };
 176
 177 static struct ctl_table sunrpc_table[] = {
 178         {
 179                 .procname       = "sunrpc",
 180                 .mode           = 0555,
 181                 .child          = debug_table
 182         },
 183         { }
 184 };
 185
 186 #endif