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 #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;
  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
 131 done:
 132         *lenp -= left;
 133         *ppos += *lenp;
 134         return 0;
 135 }
 136
 137
 138 static struct 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
 176 static struct ctl_table sunrpc_table[] = {
 177         {
 178                 .procname       = "sunrpc",
 179                 .mode           = 0555,
 180                 .child          = debug_table
 181         },
 182         { }
 183 };
 184
 185 #endif