Make the "struct if_clone" opaque to users of the cloning API. Users

now use function calls:

  if_clone_simple()
  if_clone_advanced()

to initialize a cloner, instead of macros that initialize if_clone
structure.

Discussed with:		brooks, bz, 1 year ago

1 files changed, 162 insertions, 62 deletions

diff --git a/sys/net/if_clone.c b/sys/net/if_clone.c
index 3543e2f71fca..5f68d29dc7ce 100644
--- a/sys/net/if_clone.c
+++ b/sys/net/if_clone.c
@@ -1,4 +1,5 @@
 /*-
+ * Copyright (c) 2012 Gleb Smirnoff <glebius@FreeBSD.org>
  * Copyright (c) 1980, 1986, 1993
  *	The Regents of the University of California.  All rights reserved.
  *
@@ -42,19 +43,65 @@
 
 #include <net/if.h>
 #include <net/if_clone.h>
-#if 0
-#include <net/if_dl.h>
-#endif
-#include <net/if_types.h>
 #include <net/if_var.h>
 #include <net/radix.h>
 #include <net/route.h>
 #include <net/vnet.h>
 
+/* Current IF_MAXUNIT expands maximum to 5 characters. */
+#define	IFCLOSIZ	(IFNAMSIZ - 5)
+
+/*
+ * Structure describing a `cloning' interface.
+ *
+ * List of locks
+ * (c)		const until freeing
+ * (d)		driver specific data, may need external protection.
+ * (e)		locked by if_cloners_mtx
+ * (i)		locked by ifc_mtx mtx
+ */
+struct if_clone {
+	char ifc_name[IFCLOSIZ];	/* (c) Name of device, e.g. `gif' */
+	struct unrhdr *ifc_unrhdr;	/* (c) alloc_unr(9) header */
+	int ifc_maxunit;		/* (c) maximum unit number */
+	long ifc_refcnt;		/* (i) Reference count. */
+	LIST_HEAD(, ifnet) ifc_iflist;	/* (i) List of cloned interfaces */
+	struct mtx ifc_mtx;		/* Mutex to protect members. */
+
+	enum { SIMPLE, ADVANCED } ifc_type; /* (c) */
+
+	/* (c) Driver specific cloning functions.  Called with no locks held. */
+	union {
+		struct {	/* advanced cloner */
+			ifc_match_t	*_ifc_match;
+			ifc_create_t	*_ifc_create;
+			ifc_destroy_t	*_ifc_destroy;
+		} A;
+		struct {	/* simple cloner */
+			ifcs_create_t	*_ifcs_create;
+			ifcs_destroy_t	*_ifcs_destroy;
+			int		_ifcs_minifs;	/* minimum ifs */
+
+		} S;
+	} U;
+#define	ifc_match	U.A._ifc_match
+#define	ifc_create	U.A._ifc_create
+#define	ifc_destroy	U.A._ifc_destroy
+#define	ifcs_create	U.S._ifcs_create
+#define	ifcs_destroy	U.S._ifcs_destroy
+#define	ifcs_minifs	U.S._ifcs_minifs
+
+	LIST_ENTRY(if_clone) ifc_list;	/* (e) On list of cloners */
+};
+
 static void	if_clone_free(struct if_clone *ifc);
 static int	if_clone_createif(struct if_clone *ifc, char *name, size_t len,
 		    caddr_t params);
 
+static int     ifc_simple_match(struct if_clone *, const char *);
+static int     ifc_simple_create(struct if_clone *, char *, size_t, caddr_t);
+static int     ifc_simple_destroy(struct if_clone *, struct ifnet *);
+
 static struct mtx	if_cloners_mtx;
 static VNET_DEFINE(int, if_cloners_count);
 VNET_DEFINE(LIST_HEAD(, if_clone), if_cloners);
@@ -138,18 +185,25 @@ if_clone_create(char *name, size_t len, caddr_t params)
 
 	/* Try to find an applicable cloner for this request */
 	IF_CLONERS_LOCK();
-	LIST_FOREACH(ifc, &V_if_cloners, ifc_list) {
-		if (ifc->ifc_match(ifc, name)) {
-			break;
+	LIST_FOREACH(ifc, &V_if_cloners, ifc_list)
+		if (ifc->ifc_type == SIMPLE) {
+			if (ifc_simple_match(ifc, name))
+				break;
+		} else {
+			if (ifc->ifc_match(ifc, name))
+				break;
 		}
-	}
 #ifdef VIMAGE
 	if (ifc == NULL && !IS_DEFAULT_VNET(curvnet)) {
 		CURVNET_SET_QUIET(vnet0);
-		LIST_FOREACH(ifc, &V_if_cloners, ifc_list) {
-			if (ifc->ifc_match(ifc, name))
-				break;
-		}
+		LIST_FOREACH(ifc, &V_if_cloners, ifc_list)
+			if (ifc->ifc_type == SIMPLE) {
+				if (ifc_simple_match(ifc, name))
+					break;
+			} else {
+				if (ifc->ifc_match(ifc, name))
+					break;
+			}
 		CURVNET_RESTORE();
 	}
 #endif
@@ -173,7 +227,10 @@ if_clone_createif(struct if_clone *ifc, char *name, size_t len, caddr_t params)
 	if (ifunit(name) != NULL)
 		return (EEXIST);
 
-	err = (*ifc->ifc_create)(ifc, name, len, params);
+	if (ifc->ifc_type == SIMPLE)
+		err = ifc_simple_create(ifc, name, len, params);
+	else
+		err = (*ifc->ifc_create)(ifc, name, len, params);
 	
 	if (!err) {
 		ifp = ifunit(name);
@@ -214,10 +271,14 @@ if_clone_destroy(const char *name)
 #ifdef VIMAGE
 	if (ifc == NULL && !IS_DEFAULT_VNET(curvnet)) {
 		CURVNET_SET_QUIET(vnet0);
-		LIST_FOREACH(ifc, &V_if_cloners, ifc_list) {
-			if (ifc->ifc_match(ifc, name))
-				break;
-		}
+		LIST_FOREACH(ifc, &V_if_cloners, ifc_list)
+			if (ifc->type == SIMPLE) {
+				if (ifc_simple_match(ifc, name))
+					break;
+			} else {
+				if (ifc->ifc_match(ifc, name))
+					break;
+			}
 		CURVNET_RESTORE();
 	}
 #endif
@@ -241,7 +302,7 @@ if_clone_destroyif(struct if_clone *ifc, struct ifnet *ifp)
 	int err;
 	struct ifnet *ifcifp;
 
-	if (ifc->ifc_destroy == NULL)
+	if (ifc->ifc_type == ADVANCED && ifc->ifc_destroy == NULL)
 		return(EOPNOTSUPP);
 
 	/*
@@ -266,7 +327,10 @@ if_clone_destroyif(struct if_clone *ifc, struct ifnet *ifp)
 
 	if_delgroup(ifp, ifc->ifc_name);
 
-	err =  (*ifc->ifc_destroy)(ifc, ifp);
+	if (ifc->ifc_type == SIMPLE)
+		err = ifc_simple_destroy(ifc, ifp);
+	else
+		err = (*ifc->ifc_destroy)(ifc, ifp);
 
 	if (err != 0) {
 		if_addgroup(ifp, ifc->ifc_name);
@@ -279,21 +343,29 @@ if_clone_destroyif(struct if_clone *ifc, struct ifnet *ifp)
 	return (err);
 }
 
-/*
- * Register a network interface cloner.
- */
-int
-if_clone_attach(struct if_clone *ifc)
+static struct if_clone *
+if_clone_alloc(const char *name, int maxunit)
 {
-	struct if_clone *ifc1;
+	struct if_clone *ifc;
 
-	KASSERT(ifc->ifc_name != NULL, ("%s: no name\n", __func__));
+	KASSERT(name != NULL, ("%s: no name\n", __func__));
 
+	ifc = malloc(sizeof(struct if_clone), M_CLONE, M_WAITOK | M_ZERO);
+	strncpy(ifc->ifc_name, name, IFCLOSIZ-1);
 	IF_CLONE_LOCK_INIT(ifc);
 	IF_CLONE_ADDREF(ifc);
+	ifc->ifc_maxunit = maxunit ? maxunit : IF_MAXUNIT;
 	ifc->ifc_unrhdr = new_unrhdr(0, ifc->ifc_maxunit, &ifc->ifc_mtx);
 	LIST_INIT(&ifc->ifc_iflist);
 
+	return (ifc);
+}
+	
+static int
+if_clone_attach(struct if_clone *ifc)
+{
+	struct if_clone *ifc1;
+
 	IF_CLONERS_LOCK();
 	LIST_FOREACH(ifc1, &V_if_cloners, ifc_list)
 		if (strcmp(ifc->ifc_name, ifc1->ifc_name) == 0) {
@@ -305,11 +377,63 @@ if_clone_attach(struct if_clone *ifc)
 	V_if_cloners_count++;
 	IF_CLONERS_UNLOCK();
 
-	if (ifc->ifc_attach != NULL)
-		(*ifc->ifc_attach)(ifc);
+	return (0);
+}
+
+struct if_clone *
+if_clone_advanced(const char *name, u_int maxunit, ifc_match_t match,
+	ifc_create_t create, ifc_destroy_t destroy)
+{
+	struct if_clone *ifc;
+
+	ifc = if_clone_alloc(name, maxunit);
+	ifc->ifc_type = ADVANCED;
+	ifc->ifc_match = match;
+	ifc->ifc_create = create;
+	ifc->ifc_destroy = destroy;
+
+	if (if_clone_attach(ifc) != 0) {
+		if_clone_free(ifc);
+		return (NULL);
+	}
+
 	EVENTHANDLER_INVOKE(if_clone_event, ifc);
 
-	return (0);
+	return (ifc);
+}
+
+struct if_clone *
+if_clone_simple(const char *name, ifcs_create_t create, ifcs_destroy_t destroy,
+	u_int minifs)
+{
+	struct if_clone *ifc;
+	u_int unit;
+
+	ifc = if_clone_alloc(name, 0);
+	ifc->ifc_type = SIMPLE;
+	ifc->ifcs_create = create;
+	ifc->ifcs_destroy = destroy;
+	ifc->ifcs_minifs = minifs;
+
+	if (if_clone_attach(ifc) != 0) {
+		if_clone_free(ifc);
+		return (NULL);
+	}
+
+	for (unit = 0; unit < minifs; unit++) {
+		char name[IFNAMSIZ];
+		int error;
+
+		snprintf(name, IFNAMSIZ, "%s%d", ifc->ifc_name, unit);
+		error = if_clone_createif(ifc, name, IFNAMSIZ, NULL);
+		KASSERT(error == 0,
+		    ("%s: failed to create required interface %s",
+		    __func__, name));
+	}
+
+	EVENTHANDLER_INVOKE(if_clone_event, ifc);
+
+	return (ifc);
 }
 
 /*
@@ -318,7 +442,6 @@ if_clone_attach(struct if_clone *ifc)
 void
 if_clone_detach(struct if_clone *ifc)
 {
-	struct ifc_simple_data *ifcs = ifc->ifc_data;
 
 	IF_CLONERS_LOCK();
 	LIST_REMOVE(ifc, ifc_list);
@@ -326,8 +449,8 @@ if_clone_detach(struct if_clone *ifc)
 	IF_CLONERS_UNLOCK();
 
 	/* Allow all simples to be destroyed */
-	if (ifc->ifc_attach == ifc_simple_attach)
-		ifcs->ifcs_minifs = 0;
+	if (ifc->ifc_type == SIMPLE)
+		ifc->ifcs_minifs = 0;
 
 	/* destroy all interfaces for this cloner */
 	while (!LIST_EMPTY(&ifc->ifc_iflist))
@@ -345,6 +468,7 @@ if_clone_free(struct if_clone *ifc)
 
 	IF_CLONE_LOCK_DESTROY(ifc);
 	delete_unrhdr(ifc->ifc_unrhdr);
+	free(ifc, M_CLONE);
 }
 
 /*
@@ -483,29 +607,7 @@ ifc_free_unit(struct if_clone *ifc, int unit)
 	IF_CLONE_REMREF(ifc);
 }
 
-void
-ifc_simple_attach(struct if_clone *ifc)
-{
-	int err;
-	int unit;
-	char name[IFNAMSIZ];
-	struct ifc_simple_data *ifcs = ifc->ifc_data;
-
-	KASSERT(ifcs->ifcs_minifs - 1 <= ifc->ifc_maxunit,
-	    ("%s: %s requested more units than allowed (%d > %d)",
-	    __func__, ifc->ifc_name, ifcs->ifcs_minifs,
-	    ifc->ifc_maxunit + 1));
-
-	for (unit = 0; unit < ifcs->ifcs_minifs; unit++) {
-		snprintf(name, IFNAMSIZ, "%s%d", ifc->ifc_name, unit);
-		err = if_clone_createif(ifc, name, IFNAMSIZ, NULL);
-		KASSERT(err == 0,
-		    ("%s: failed to create required interface %s",
-		    __func__, name));
-	}
-}
-
-int
+static int
 ifc_simple_match(struct if_clone *ifc, const char *name)
 {
 	const char *cp;
@@ -526,14 +628,13 @@ ifc_simple_match(struct if_clone *ifc, const char *name)
 	return (1);
 }
 
-int
+static int
 ifc_simple_create(struct if_clone *ifc, char *name, size_t len, caddr_t params)
 {
 	char *dp;
 	int wildcard;
 	int unit;
 	int err;
-	struct ifc_simple_data *ifcs = ifc->ifc_data;
 
 	err = ifc_name2unit(name, &unit);
 	if (err != 0)
@@ -545,7 +646,7 @@ ifc_simple_create(struct if_clone *ifc, char *name, size_t len, caddr_t params)
 	if (err != 0)
 		return (err);
 
-	err = ifcs->ifcs_create(ifc, unit, params);
+	err = ifc->ifcs_create(ifc, unit, params);
 	if (err != 0) {
 		ifc_free_unit(ifc, unit);
 		return (err);
@@ -569,18 +670,17 @@ ifc_simple_create(struct if_clone *ifc, char *name, size_t len, caddr_t params)
 	return (0);
 }
 
-int
+static int
 ifc_simple_destroy(struct if_clone *ifc, struct ifnet *ifp)
 {
 	int unit;
-	struct ifc_simple_data *ifcs = ifc->ifc_data;
 
 	unit = ifp->if_dunit;
 
-	if (unit < ifcs->ifcs_minifs) 
+	if (unit < ifc->ifcs_minifs) 
 		return (EINVAL);
 
-	ifcs->ifcs_destroy(ifp);
+	ifc->ifcs_destroy(ifp);
 
 	ifc_free_unit(ifc, unit);