Setting the maximum interface count now does the right thing.

diff --git a/unet.c b/unet.c
index 09020eb..7fdc317 100644 (file)
--- a/unet.c
+++ b/unet.c
@@ -1,6 +1,6 @@
 /* -*-c-*-
  *
- * $Id: unet.c,v 1.1 2001/01/25 22:03:39 mdw Exp $
+ * $Id: unet.c,v 1.2 2001/02/03 18:39:59 mdw Exp $
  *
  * User-space network device support.
  *
@@ -29,6 +29,9 @@
 /*----- Revision history --------------------------------------------------*
  *
  * $Log: unet.c,v $
+ * Revision 1.2  2001/02/03 18:39:59  mdw
+ * Setting the maximum interface count now does the right thing.
+ *
  * Revision 1.1  2001/01/25 22:03:39  mdw
  * Initial check-in (somewhat belated).
  *
@@ -122,6 +125,7 @@ static int unet_npersist = UNET_NPERSIST;
 static int unet_maxif = UNET_MAXIF;
 static struct unet *unet_persistent;
 static struct unet *unet_list = 0;
+static int unet_nif = 0;
 
 MODULE_PARM(unet_npersist, "i");
 MODULE_PARM(unet_maxif, "i");
@@ -519,21 +523,20 @@ static int unet_devopen(struct inode *ino, struct file *f)
 
   /* --- Otherwise we've got to create a new one --- */
 
-  else {
+  else if (seq == UNET_TRANSMINOR) {
 
     /* --- Try to find a spare sequence number --- */
 
+    if (unet_nif >= unet_maxif) {
+      printk(KERN_NOTICE "unet: no interfaces left\n");
+      e = -ENFILE;
+      goto tidy_0;
+    }
     for (seq = unet_npersist, up = &unet_list; *up != 0;
         seq++, up = &(*up)->next) {
       if ((*up)->seq > seq)
        break;
-      if (seq >= unet_maxif) {
-       printk("unet: all unets are occupied\n");
-       e = -ENFILE;
-       goto tidy_0;
-      }
     }
-
     D( printk(KERN_DEBUG "unet: allocated sequence number %d\n", seq); )
 
     /* --- Allocate a new block --- */
@@ -549,6 +552,7 @@ static int unet_devopen(struct inode *ino, struct file *f)
     if ((e = unet_setup(u, seq)) != 0)
       goto tidy_1;
     u->f |= UNIF_TRANS;
+    unet_nif++;
 
     /* --- Link the block into the list --- */
 
@@ -560,7 +564,8 @@ static int unet_devopen(struct inode *ino, struct file *f)
 
     D( printk(KERN_DEBUG "unet: opened transient %d\n", seq);
        unet_dumpBlock(u); )
-  }
+  } else
+    return (-ENODEV);
 
   /* --- Done --- */
 
@@ -596,12 +601,14 @@ static int unet_devclose(struct inode *ino, struct file *f)
   /* --- A transient unet needs to be destroyed --- */
 
   if (u->f & UNIF_TRANS) {
+    int seq = u->seq;
     *u->prev = u->next;
     if (u->next)
       u->next->prev = u->prev;
     unet_kill(u);
     kfree(u);
-    D( printk(KERN_DEBUG "unet: released transient unet\n"); )
+    unet_nif--;
+    D( printk(KERN_DEBUG "unet: released transient %d\n", seq); )
   }
 
   /* --- A persistent unet needs to be shutdown --- */
@@ -863,6 +870,8 @@ static int unet_devioctl(struct inode *ino,
       int n = !!arg;
       int o = !!(u->f & UNIF_DEBUG);
 
+      if (!capable(CAP_SYS_ADMIN))
+       return (-EPERM);
       if (n || o) {
        printk(KERN_DEBUG "unet: UNIOCSDEBUG on %s: %s\n", u->name,
               (o && n) ? "debugging still on" :
@@ -906,12 +915,16 @@ static int unet_devioctl(struct inode *ino,
 
 #if UNET_DEBUG == UNET_DEBUGRUNTIME
     case UNIOCSGDEBUG:
-      printk(KERN_DEBUG "unet: UNIOCSGDEBUG: set global debug: %s\n",
-            (arg && unet_debug) ? "debugging still on" :
-             (!arg && unet_debug) ? "debugging turned off" :
-            (arg && !unet_debug) ? "debugging turned on" :
-            (!arg && !unet_debug) ? "you can't see this message" :
-            "Logic failure: universe exploding");
+      if (!capable(CAP_SYS_ADMIN))
+       return (-EPERM);
+      if (arg || unet_debug) {
+       printk(KERN_DEBUG "unet: UNIOCSGDEBUG: set global debug: %s\n",
+              (arg && unet_debug) ? "debugging still on" :
+              (!arg && unet_debug) ? "debugging turned off" :
+              (arg && !unet_debug) ? "debugging turned on" :
+              (!arg && !unet_debug) ? "you can't see this message" :
+              "Logic failure: universe exploding");
+      }
       unet_debug = !!arg;
       break;
 #endif
@@ -935,15 +948,18 @@ static int unet_devioctl(struct inode *ino,
     /* --- @UNIOCSMAXIF@ --- */
 
     case UNIOCSMAXIF:
-      e = -EINVAL;
+      if (!capable(CAP_SYS_ADMIN))
+       return (-EPERM);
+      D( printk(KERN_DEBUG "unet: UNIOCSMAXIF: "
+               "arg = %ld; npersist = %d; nif = %d\n",
+               arg, unet_npersist, unet_nif); )
       if (arg < unet_npersist || arg > INT_MAX)
        return (-EINVAL);
-      for (u = unet_list; u; u = u->next) {
-       if (u->seq >= unet_npersist)
-         return (-EBUSY);
-      }
+      if (arg < unet_nif)
+       return (-EBUSY);
       unet_maxif = arg;
-      D( printk(KERN_DEBUG "unet: UNIOCSMAXIF: unet_maxif = %d\n",
+      e = 0;
+      D( printk(KERN_DEBUG "unet: UNIOCSMAXIF: set unet_maxif = %d\n",
                unet_maxif); )
       break;
 
@@ -1016,6 +1032,7 @@ __initfunc(int unet_init(void))
       goto tidy_2;
     }
   }
+  unet_nif = unet_npersist;
 
   /* --- Done --- */
 

diff --git a/unet.texi b/unet.texi
index 4dd7338..8ffff55 100644 (file)
--- a/unet.texi
+++ b/unet.texi
@@ -1,6 +1,6 @@
 \input texinfo @c -*-texinfo-*-
 @c
-@c $Id: unet.texi,v 1.1 2001/01/25 22:03:39 mdw Exp $
+@c $Id: unet.texi,v 1.2 2001/02/03 18:39:59 mdw Exp $
 @c
 @c Manual for usernet device
 @c
@@ -10,6 +10,9 @@
 @c ----- Revision history ---------------------------------------------------
 @c
 @c $Log: unet.texi,v $
+@c Revision 1.2  2001/02/03 18:39:59  mdw
+@c Setting the maximum interface count now does the right thing.
+@c
 @c Revision 1.1  2001/01/25 22:03:39  mdw
 @c Initial check-in (somewhat belated).
 @c
@@ -615,6 +618,15 @@ is set; if zero, the flag is cleared.
 Dumps an attachment's information to the kernel log device.
 @end deffn
 
+@deffn {@code{ioctl} call} UNIOCGMAXIF
+Returns the total number of attachments permitted.
+@end deffn
+
+@deffn {@code{ioctl} call} UNIOCSMAXIF
+Configures the total number of attachments permitted.  It is an error to
+reduce this below the number of attachments currently in existence.
+@end deffn
+
 
 @node Sending and receiving,  , Configuring the interface, Programming
 @section Sending and receiving

diff --git a/unetcfg.c b/unetcfg.c
index dec5a9a..4b98e0e 100644 (file)
--- a/unetcfg.c
+++ b/unetcfg.c
@@ -1,6 +1,6 @@
 /* -*-c-*-
  *
- * $Id: unetcfg.c,v 1.1 2001/01/25 22:03:39 mdw Exp $
+ * $Id: unetcfg.c,v 1.2 2001/02/03 18:39:59 mdw Exp $
  *
  * User-space network device support.
  *
@@ -29,6 +29,9 @@
 /*----- Revision history --------------------------------------------------*
  *
  * $Log: unetcfg.c,v $
+ * Revision 1.2  2001/02/03 18:39:59  mdw
+ * Setting the maximum interface count now does the right thing.
+ *
  * Revision 1.1  2001/01/25 22:03:39  mdw
  * Initial check-in (somewhat belated).
  *
@@ -607,8 +610,7 @@ attachments inherit their debug flags from the global flag.\n\
 
   { "maxif", 0, cmd_maxif,
     "maxif [MAX]", "set maximum number of interfaces allowed", "\
-Configures the maximum number of interfaces allowed (actually, the highest\n\
-number of any interface).\n\
+Configures the maximum number of interfaces allowed.\n\
 " },
 
   { "help", 0, cmd_help,