Change the generated VOP_ macro implementations to improve type checking

and KASSERT coverage.

After this check there is only one "nasty" cast in this code but there
is a KASSERT to protect against the wrong argument structure behind
that cast.

Un-inlining the meat of VOP_FOO() saves 35kB of text segment on a typical
kernel with no change in performance.

We also now run the checking and tracing on VOP's which have been layered
by nullfs, umapfs, deadfs or unionfs.

    Add new (non-inline) VOP_FOO_AP() functions which take a "struct
    foo_args" argument and does everything the VOP_FOO() macros
    used to do with checks and debugging code.

    Add KASSERT to VOP_FOO_AP() check for argument type being
    correct.

    Slim down VOP_FOO() inline functions to just stuff arguments
    into the struct foo_args and call VOP_FOO_AP().

    Put function pointer to VOP_FOO_AP() into vop_foo_desc structure
    and make VCALL() use it instead of the current offsetoff() hack.

    Retire vcall() which implemented the offsetoff()

    Make deadfs and unionfs use VOP_FOO_AP() calls instead of
    VCALL(), we know which specific call we want already.

    Remove unneeded arguments to VCALL() in nullfs and umapfs bypass
    functions.

    Remove unused vdesc_offset and VOFFSET().

    Generally improve style/readability of the generated code.

7 files changed, 103 insertions, 111 deletions

diff --git a/sys/fs/deadfs/dead_vnops.c b/sys/fs/deadfs/dead_vnops.c
index 787e510..00f4015 100644
--- a/sys/fs/deadfs/dead_vnops.c
+++ b/sys/fs/deadfs/dead_vnops.c
@@ -176,7 +176,7 @@ dead_ioctl(ap)
 	if (!chkvnlock(ap->a_vp))
 		return (ENOTTY);
 	/* XXX: Doesn't this just recurse back here ? */
-	return (VCALL(ap->a_vp, VOFFSET(vop_ioctl), ap));
+	return (VOP_IOCTL_AP(ap));
 }
 
 
@@ -203,7 +203,7 @@ dead_lock(ap)
 	}
 	if (!chkvnlock(vp))
 		return (0);
-	return (VCALL(vp, VOFFSET(vop_lock), ap));
+	return (VOP_LOCK_AP(ap));
 }
 
 /*
diff --git a/sys/fs/nullfs/null_vnops.c b/sys/fs/nullfs/null_vnops.c
index 349d00b..7d32bc5 100644
--- a/sys/fs/nullfs/null_vnops.c
+++ b/sys/fs/nullfs/null_vnops.c
@@ -296,7 +296,7 @@ null_bypass(ap)
 	 * with the modified argument structure.
 	 */
 	if (vps_p[0] && *vps_p[0])
-		error = VCALL(*(vps_p[0]), descp->vdesc_offset, ap);
+		error = VCALL(ap);
 	else {
 		printf("null_bypass: no map for %s\n", descp->vdesc_name);
 		error = EINVAL;
diff --git a/sys/fs/umapfs/umap_vnops.c b/sys/fs/umapfs/umap_vnops.c
index 010e291..c7803f0 100644
--- a/sys/fs/umapfs/umap_vnops.c
+++ b/sys/fs/umapfs/umap_vnops.c
@@ -197,7 +197,7 @@ umap_bypass(ap)
 	 * Call the operation on the lower layer
 	 * with the modified argument structure.
 	 */
-	error = VCALL(*(vps_p[0]), descp->vdesc_offset, ap);
+	error = VCALL(ap);
 
 	/*
 	 * Maintain the illusion of call-by-value
diff --git a/sys/fs/unionfs/union_vnops.c b/sys/fs/unionfs/union_vnops.c
index 596adc9..2dcfd2d 100644
--- a/sys/fs/unionfs/union_vnops.c
+++ b/sys/fs/unionfs/union_vnops.c
@@ -829,7 +829,7 @@ union_close(ap)
 		vp = un->un_lowervp;
 	}
 	ap->a_vp = vp;
-	return (VCALL(vp, VOFFSET(vop_close), ap));
+	return (VOP_CLOSE_AP(ap));
 }
 
 /*
@@ -872,7 +872,7 @@ union_access(ap)
 
 	if ((vp = union_lock_upper(un, td)) != NULLVP) {
 		ap->a_vp = vp;
-		error = VCALL(vp, VOFFSET(vop_access), ap);
+		error = VOP_ACCESS_AP(ap);
 		union_unlock_upper(vp, td);
 		return(error);
 	}
@@ -888,7 +888,7 @@ union_access(ap)
 		if ((un->un_vnode->v_mount->mnt_flag & MNT_RDONLY) == 0)
 			ap->a_mode &= ~VWRITE;
 
-		error = VCALL(vp, VOFFSET(vop_access), ap);
+		error = VOP_ACCESS_AP(ap);
 		if (error == 0) {
 			struct union_mount *um;
 
@@ -896,7 +896,7 @@ union_access(ap)
 
 			if (um->um_op == UNMNT_BELOW) {
 				ap->a_cred = um->um_cred;
-				error = VCALL(vp, VOFFSET(vop_access), ap);
+				error = VOP_ACCESS_AP(ap);
 			}
 		}
 		VOP_UNLOCK(vp, 0, td);
@@ -1119,7 +1119,7 @@ union_lease(ap)
 	struct vnode *ovp = OTHERVP(ap->a_vp);
 
 	ap->a_vp = ovp;
-	return (VCALL(ovp, VOFFSET(vop_lease), ap));
+	return (VOP_LEASE_AP(ap));
 }
 
 static int
@@ -1136,7 +1136,7 @@ union_ioctl(ap)
 	struct vnode *ovp = OTHERVP(ap->a_vp);
 
 	ap->a_vp = ovp;
-	return (VCALL(ovp, VOFFSET(vop_ioctl), ap));
+	return (VOP_IOCTL_AP(ap));
 }
 
 static int
@@ -1151,7 +1151,7 @@ union_poll(ap)
 	struct vnode *ovp = OTHERVP(ap->a_vp);
 
 	ap->a_vp = ovp;
-	return (VCALL(ovp, VOFFSET(vop_poll), ap));
+	return (VOP_POLL_AP(ap));
 }
 
 static int
@@ -1594,7 +1594,7 @@ union_readdir(ap)
 
 	if ((uvp = union_lock_upper(un, td)) != NULLVP) {
 		ap->a_vp = uvp;
-		error = VCALL(uvp, VOFFSET(vop_readdir), ap);
+		error = VOP_READDIR_AP(ap);
 		union_unlock_upper(uvp, td);
 	}
 	return(error);
@@ -1618,7 +1618,7 @@ union_readlink(ap)
 	KASSERT(vp != NULL, ("union_readlink: backing vnode missing!"));
 
 	ap->a_vp = vp;
-	error = VCALL(vp, VOFFSET(vop_readlink), ap);
+	error = VOP_READLINK_AP(ap);
 	union_unlock_other(vp, td);
 
 	return (error);
@@ -1785,7 +1785,7 @@ union_pathconf(ap)
 	KASSERT(vp != NULL, ("union_pathconf: backing vnode missing!"));
 
 	ap->a_vp = vp;
-	error = VCALL(vp, VOFFSET(vop_pathconf), ap);
+	error = VOP_PATHCONF_AP(ap);
 	union_unlock_other(vp, td);
 
 	return (error);
@@ -1804,7 +1804,7 @@ union_advlock(ap)
 	register struct vnode *ovp = OTHERVP(ap->a_vp);
 
 	ap->a_vp = ovp;
-	return (VCALL(ovp, VOFFSET(vop_advlock), ap));
+	return (VOP_ADVLOCK_AP(ap));
 }
 
 
@@ -1851,7 +1851,7 @@ union_getacl(ap)
 
 	vp = union_lock_other(un, ap->a_td);
 	ap->a_vp = vp;
-	error = VCALL(vp, VOFFSET(vop_getacl), ap);
+	error = VOP_GETACL_AP(ap);
 	union_unlock_other(vp, ap->a_td);
 
 	return (error);
@@ -1873,7 +1873,7 @@ union_setacl(ap)
 
 	vp = union_lock_other(un, ap->a_td);
 	ap->a_vp = vp;
-	error = VCALL(vp, VOFFSET(vop_setacl), ap);
+	error = VOP_SETACL_AP(ap);
 	union_unlock_other(vp, ap->a_td);
 
 	return (error);
@@ -1892,7 +1892,7 @@ union_aclcheck(ap)
 	struct vnode *ovp = OTHERVP(ap->a_vp);
 
 	ap->a_vp = ovp;
-	return (VCALL(ovp, VOFFSET(vop_aclcheck), ap));
+	return (VOP_ACLCHECK_AP(ap));
 }
 
 static int
@@ -1910,7 +1910,7 @@ union_closeextattr(ap)
 
 	vp = union_lock_other(un, ap->a_td);
 	ap->a_vp = vp;
-	error = VCALL(vp, VOFFSET(vop_closeextattr), ap);
+	error = VOP_CLOSEEXTATTR_AP(ap);
 	union_unlock_other(vp, ap->a_td);
 
 	return (error);
@@ -1934,7 +1934,7 @@ union_getextattr(ap)
 
 	vp = union_lock_other(un, ap->a_td);
 	ap->a_vp = vp;
-	error = VCALL(vp, VOFFSET(vop_getextattr), ap);
+	error = VOP_GETEXTATTR_AP(ap);
 	union_unlock_other(vp, ap->a_td);
 
 	return (error);
@@ -1957,7 +1957,7 @@ union_listextattr(ap)
 
 	vp = union_lock_other(un, ap->a_td);
 	ap->a_vp = vp;
-	error = VCALL(vp, VOFFSET(vop_listextattr), ap);
+	error = VOP_LISTEXTATTR_AP(ap);
 	union_unlock_other(vp, ap->a_td);
 
 	return (error);
@@ -1977,7 +1977,7 @@ union_openextattr(ap)
 
 	vp = union_lock_other(un, ap->a_td);
 	ap->a_vp = vp;
-	error = VCALL(vp, VOFFSET(vop_openextattr), ap);
+	error = VOP_OPENEXTATTR_AP(ap);
 	union_unlock_other(vp, ap->a_td);
 
 	return (error);
@@ -1999,7 +1999,7 @@ union_deleteextattr(ap)
 
 	vp = union_lock_other(un, ap->a_td);
 	ap->a_vp = vp;
-	error = VCALL(vp, VOFFSET(vop_deleteextattr), ap);
+	error = VOP_DELETEEXTATTR_AP(ap);
 	union_unlock_other(vp, ap->a_td);
 
 	return (error);
@@ -2022,7 +2022,7 @@ union_setextattr(ap)
 
 	vp = union_lock_other(un, ap->a_td);
 	ap->a_vp = vp;
-	error = VCALL(vp, VOFFSET(vop_setextattr), ap);
+	error = VOP_SETEXTATTR_AP(ap);
 	union_unlock_other(vp, ap->a_td);
 
 	return (error);
@@ -2043,7 +2043,7 @@ union_setlabel(ap)
 
 	vp = union_lock_other(un, ap->a_td);
 	ap->a_vp = vp;
-	error = VCALL(vp, VOFFSET(vop_setlabel), ap);
+	error = VOP_SETLABEL_AP(ap);
 	union_unlock_other(vp, ap->a_td);
 
 	return (error);
diff --git a/sys/kern/vfs_init.c b/sys/kern/vfs_init.c
index e4c4f40..61d2675 100644
--- a/sys/kern/vfs_init.c
+++ b/sys/kern/vfs_init.c
@@ -89,32 +89,6 @@ struct vattr va_null;
  * Routines having to do with the management of the vnode table.
  */
 
-/*
- * XXX: hack alert
- */
-int
-vcall(struct vnode *vp, u_int off, void *ap)
-{
-	struct vop_vector *vop = vp->v_op;
-	vop_bypass_t **bpt;
-	int rc;
-	
-	for(;;) {
-		bpt = (void *)((u_char *)vop + off);
-		if (vop != NULL && *bpt == NULL && vop->vop_bypass == NULL) {
-			vop = vop->vop_default;
-			continue;
-		}
-		break;
-	}
-	KASSERT(vop != NULL, ("No VCALL(%p...)", vp));
-	if (*bpt != NULL)
-		rc = (*bpt)(ap);
-	else
-		rc = vop->vop_bypass(ap);
-	return (rc);
-}
-
 struct vfsconf *
 vfs_byname(const char *name)
 {
diff --git a/sys/sys/vnode.h b/sys/sys/vnode.h
index 12fe029..8b75ce7 100644
--- a/sys/sys/vnode.h
+++ b/sys/sys/vnode.h
@@ -409,6 +409,17 @@ extern void	(*lease_updatetime)(int deltat);
 #define	VDESC_VPP_WILLRELE	0x0200
 
 /*
+ * A generic structure.
+ * This can be used by bypass routines to identify generic arguments.
+ */
+struct vop_generic_args {
+	struct vnodeop_desc *a_desc;
+	/* other random data follows, presumably */
+};
+
+typedef int vop_bypass_t(struct vop_generic_args *);
+
+/*
  * VDESC_NO_OFFSET is used to identify the end of the offset list
  * and in places where no such field exists.
  */
@@ -418,9 +429,9 @@ extern void	(*lease_updatetime)(int deltat);
  * This structure describes the vnode operation taking place.
  */
 struct vnodeop_desc {
-	int	 vdesc_offset;		/* offset in vector,first for speed */
 	char	*vdesc_name;		/* a readable name for debugging */
 	int	 vdesc_flags;		/* VDESC_* flags */
+	vop_bypass_t	*vdesc_call;	/* Function to call */
 
 	/*
 	 * These ops are used by bypass routines to map and locate arguments.
@@ -451,14 +462,6 @@ extern struct vnodeop_desc *vnodeop_descs[];
 #define	VOPARG_OFFSETTO(s_type, s_offset, struct_p) \
     ((s_type)(((char*)(struct_p)) + (s_offset)))
 
-/*
- * A generic structure.
- * This can be used by bypass routines to identify generic arguments.
- */
-struct vop_generic_args {
-	struct vnodeop_desc *a_desc;
-	/* other random data follows, presumably */
-};
 
 #ifdef DEBUG_VFS_LOCKS
 /*
@@ -521,9 +524,8 @@ void	vop_unlock_pre(void *a);
 /*
  * This call works for vnodes in the kernel.
  */
-#define VCALL(a, b, c) vcall((a), (b), (c))
+#define VCALL(c) ((c)->a_desc->vdesc_call(c))
 #define VDESC(OP) (& __CONCAT(OP,_desc))
-#define VOFFSET(OP) (VDESC(OP)->vdesc_offset)
 
 /*
  * VMIO support inline
@@ -674,7 +676,6 @@ int	vop_panic(struct vop_generic_args *ap);
 int	vop_stdcreatevobject(struct vop_createvobject_args *ap);
 int	vop_stddestroyvobject(struct vop_destroyvobject_args *ap);
 int	vop_stdgetvobject(struct vop_getvobject_args *ap);
-int	vcall(struct vnode *vp, u_int off, void *ap);
 
 void	vfree(struct vnode *);
 void	vput(struct vnode *vp);
diff --git a/sys/tools/vnode_if.awk b/sys/tools/vnode_if.awk
index 0063de2..5474589 100644
--- a/sys/tools/vnode_if.awk
+++ b/sys/tools/vnode_if.awk
@@ -62,25 +62,27 @@ function printh(s) {print s > hfile;}
 function printp(s) {print s > pfile;}
 function printq(s) {print s > qfile;}
 
-function add_debug_code(name, arg, pos)
+function add_debug_code(name, arg, pos, ind)
 {
 	if (arg == "vpp")
-		arg = "*vpp";
+		star = "*";
+	else
+		star = "";
 	if (lockdata[name, arg, pos] && (lockdata[name, arg, pos] != "-")) {
 		if (arg ~ /^\*/) {
-			printh("\tif ("substr(arg, 2)" != NULL) {");
+			printc(ind"if ("substr(arg, 2)" != NULL) {");
 		}
-		printh("\tASSERT_VI_UNLOCKED("arg", \""uname"\");");
+		printc(ind"ASSERT_VI_UNLOCKED("star"a->a_"arg", \""uname"\");");
 		# Add assertions for locking
 		if (lockdata[name, arg, pos] == "L")
-			printh("\tASSERT_VOP_LOCKED("arg", \""uname"\");");
+			printc(ind"ASSERT_VOP_LOCKED(" star "a->a_"arg", \""uname"\");");
 		else if (lockdata[name, arg, pos] == "U")
-			printh("\tASSERT_VOP_UNLOCKED("arg", \""uname"\");");
+			printc(ind"ASSERT_VOP_UNLOCKED(" star "a->a_"arg", \""uname"\");");
 		else if (0) {
 			# XXX More checks!
 		}
 		if (arg ~ /^\*/) {
-			printh("\t}");
+			printc("ind}");
 		}
 	}
 }
@@ -88,18 +90,18 @@ function add_debug_code(name, arg, pos)
 function add_debug_pre(name)
 {
 	if (lockdata[name, "pre"]) {
-		printh("#ifdef	DEBUG_VFS_LOCKS");
-		printh("\t"lockdata[name, "pre"]"(&a);");
-		printh("#endif");
+		printc("#ifdef	DEBUG_VFS_LOCKS");
+		printc("\t"lockdata[name, "pre"]"(a);");
+		printc("#endif");
 	}
 }
 
 function add_debug_post(name)
 {
 	if (lockdata[name, "post"]) {
-		printh("#ifdef	DEBUG_VFS_LOCKS");
-		printh("\t"lockdata[name, "post"]"(&a, rc);");
-		printh("#endif");
+		printc("#ifdef	DEBUG_VFS_LOCKS");
+		printc("\t"lockdata[name, "post"]"(a, rc);");
+		printc("#endif");
 	}
 }
 
@@ -159,8 +161,6 @@ if (pfile) {
 
 if (qfile) {
 	printq(common_head)
-	printq("struct vop_generic_args;")
-	printq("typedef int vop_bypass_t(struct vop_generic_args *);\n")
 }
 
 if (hfile) {
@@ -176,9 +176,9 @@ if (cfile) {
 	    "#include <sys/vnode.h>\n" \
 	    "\n" \
 	    "struct vnodeop_desc vop_default_desc = {\n" \
-	    "	1,\t\t\t/* special case, vop_default => 1 */\n" \
 	    "	\"default\",\n" \
 	    "	0,\n" \
+	    "	(void *)(uintptr_t)vop_panic,\n" \
 	    "	NULL,\n" \
 	    "	VDESC_NO_OFFSET,\n" \
 	    "	VDESC_NO_OFFSET,\n" \
@@ -196,8 +196,6 @@ while ((getline < srcfile) > 0) {
 		    $2 !~ /^[a-z]+$/  ||  $3 !~ /^[a-z]+$/  || \
 		    $4 !~ /^.$/  ||  $5 !~ /^.$/  ||  $6 !~ /^.$/)
 			continue;
-		if ($3 == "vpp")
-			$3 = "*vpp";
 		lockdata["vop_" $2, $3, "Entry"] = $4;
 		lockdata["vop_" $2, $3, "OK"]    = $5;
 		lockdata["vop_" $2, $3, "Error"] = $6;			
@@ -280,9 +278,10 @@ while ((getline < srcfile) > 0) {
 		ctrargs = 6;
 	else
 		ctrargs = numargs;
-	ctrstr = "\tCTR" ctrargs "(KTR_VOP, " ctrstr ")\"";
-	for (i = 0; i < ctrargs; ++i)
-		ctrstr = ctrstr ", " args[i];
+	ctrstr = "\tCTR" ctrargs "(KTR_VOP,\n\t    " ctrstr ")\",\n\t    ";
+	ctrstr = ctrstr "a->a_" args[0];
+	for (i = 1; i < ctrargs; ++i)
+		ctrstr = ctrstr ", a->a_" args[i];
 	ctrstr = ctrstr ");";
 
 	if (pfile) {
@@ -299,44 +298,30 @@ while ((getline < srcfile) > 0) {
 		for (i = 0; i < numargs; ++i)
 			printh("\t" t_spc(types[i]) "a_" args[i] ";");
 		printh("};");
+		printh("");
 
 		# Print out extern declaration.
 		printh("extern struct vnodeop_desc " name "_desc;");
+		printh("");
 
-		# Print out function.
+		# Print out function prototypes.
+		printh("int " uname "_AP(struct " name "_args *);");
+		printh("");
 		printh("static __inline int " uname "(");
 		for (i = 0; i < numargs; ++i) {
 			printh("\t" t_spc(types[i]) args[i] \
 			    (i < numargs - 1 ? "," : ")"));
 		}
-		printh("{\n\tstruct " name "_args a;");
-		printh("\tint rc;");
+		printh("{");
+		printh("\tstruct " name "_args a;");
+		printh("");
 		printh("\ta.a_gen.a_desc = VDESC(" name ");");
 		for (i = 0; i < numargs; ++i)
 			printh("\ta.a_" args[i] " = " args[i] ";");
-		for (i = 0; i < numargs; ++i)
-			add_debug_code(name, args[i], "Entry");
-		add_debug_pre(name);
-		printh("\t{")
-		printh("\t\tstruct vop_vector *vop = "args[0]"->v_op;")
-		printh("\t\twhile(vop != NULL && vop->"name" == NULL && vop->vop_bypass == NULL)")
-		printh("\t\t\tvop = vop->vop_default;")
-		printh("\t\tKASSERT(vop != NULL, (\"No "name"(%p...)\", "args[0]"));")
-		printh("\t\tif (vop->"name" != NULL)")
-		printh("\t\t\trc = vop->"name"(&a);")
-		printh("\t\telse")
-		printh("\t\t\trc = vop->vop_bypass(&a.a_gen);")
-		printh("\t}")
-		printh(ctrstr);
-		printh("if (rc == 0) {");
-		for (i = 0; i < numargs; ++i)
-			add_debug_code(name, args[i], "OK");
-		printh("} else {");
-		for (i = 0; i < numargs; ++i)
-			add_debug_code(name, args[i], "Error");
+		printh("\treturn (" uname "_AP(&a));");
 		printh("}");
-		add_debug_post(name);
-		printh("\treturn (rc);\n}");
+
+		printh("");
 	}
 
 	if (cfile) {
@@ -362,10 +347,40 @@ while ((getline < srcfile) > 0) {
 		printc("\tVDESC_NO_OFFSET");
 		printc("};");
 
+		# Print out function.
+		printc("\nint\n" uname "_AP(struct " name "_args *a)");
+		printc("{");
+		printc("\tint rc;");
+		printc("\tstruct vnode *vp = a->a_" args[0]";");
+		printc("\tstruct vop_vector *vop = vp->v_op;");
+		printc("");
+		printc("\tKASSERT(a->a_gen.a_desc == VDESC(" name "),");
+		printc("\t    (\"Wrong a_desc in " name "(%p, %p)\", vp, a));");
+		printc("\twhile(vop != NULL && \\");
+		printc("\t    vop->"name" == NULL && vop->vop_bypass == NULL)")
+		printc("\t\tvop = vop->vop_default;")
+		printc("\tKASSERT(vop != NULL, (\"No "name"(%p, %p)\", vp, a));")
+		for (i = 0; i < numargs; ++i)
+			add_debug_code(name, args[i], "Entry", "\t");
+		add_debug_pre(name);
+		printc("\tif (vop->"name" != NULL)")
+		printc("\t\trc = vop->"name"(a);")
+		printc("\telse")
+		printc("\t\trc = vop->vop_bypass(&a->a_gen);")
+		printc(ctrstr);
+		printc("\tif (rc == 0) {");
+		for (i = 0; i < numargs; ++i)
+			add_debug_code(name, args[i], "OK", "\t\t");
+		printc("\t} else {");
+		for (i = 0; i < numargs; ++i)
+			add_debug_code(name, args[i], "Error", "\t\t");
+		printc("\t}");
+		add_debug_post(name);
+		printc("\treturn (rc);");
+		printc("}\n");
+
 		# Print out the vnodeop_desc structure.
 		printc("struct vnodeop_desc " name "_desc = {");
-		# offset
-		printc("\toffsetof(struct vop_vector, "name"),");
 		# printable name
 		printc("\t\"" name "\",");
 		# flags
@@ -381,6 +396,8 @@ while ((getline < srcfile) > 0) {
 			releflags = "0";
 		printc("\t" releflags vppwillrele ",");
 
+		# function to call
+		printc("\t(void*)(uintptr_t)" uname "_AP,");
 		# vp offsets
 		printc("\t" name "_vp_offsets,");
 		# vpp (if any)