opnsense-src/sys/tools/vnode_if.awk
Mark Johnston 3bd8fab241 vfs: Move DEBUG_VFS_LOCKS checks to INVARIANTS
It is easy to forget to configure DEBUG_VFS_LOCKS, and when one does, no
vnode lock assertions are checked when INVARIANTS is configured, so bugs
can arise.  This has happened to me more than once, and the overhead
over DEBUG_VFS_LOCKS does not appear to be high enough to prohibit
folding it into INVARIANTS, so let's do that.

The change makes vnode lock assertions useful in plain INVARIANTS
kernels, and guards VOP debug routines on INVARIANTS rather than
DEBUG_VFS_LOCKS.  Further, invariants are now checked by plain
assertions rather than having various sysctls to finely control what
happens the checks fail.  The extra complexity didn't seem particularly
useful and is at odds with how we handle debugging most everywhere else.

Reviewed by:	kib
MFC after:	2 weeks
Differential Revision:	https://reviews.freebsd.org/D51402
2025-08-03 21:27:28 +00:00

512 lines
14 KiB
Awk

#!/usr/bin/awk -f
#-
# SPDX-License-Identifier: BSD-3-Clause
#
# Copyright (c) 1992, 1993
# The Regents of the University of California. All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
# 1. Redistributions of source code must retain the above copyright
# notice, this list of conditions and the following disclaimer.
# 2. Redistributions in binary form must reproduce the above copyright
# notice, this list of conditions and the following disclaimer in the
# documentation and/or other materials provided with the distribution.
# 3. Neither the name of the University nor the names of its contributors
# may be used to endorse or promote products derived from this software
# without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
# ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
# SUCH DAMAGE.
# Script to produce VFS front-end sugar.
#
# usage: vnode_if.awk <srcfile> [-c | -h | -p | -q]
# (where <srcfile> is currently /sys/kern/vnode_if.src)
# The source file must have a .src extension
#
function usage()
{
print "usage: vnode_if.awk <srcfile> [-c|-h|-p|-q]";
exit 1;
}
function die(msg, what)
{
printf srcfile "(" fnr "): " > "/dev/stderr";
printf msg "\n", what > "/dev/stderr";
exit 1;
}
function t_spc(type)
{
# Append a space if the type is not a pointer
return (type ~ /\*$/) ? type : type " ";
}
# These are just for convenience ...
function printc(s) {print s > cfile;}
function printh(s) {print s > hfile;}
function printp(s) {print s > pfile;}
function printq(s) {print s > qfile;}
function add_debug_code(name, arg, pos, ind)
{
if (arg == "vpp")
star = "*";
else
star = "";
if (lockdata[name, arg, pos] && (lockdata[name, arg, pos] != "-")) {
printc(ind"ASSERT_VI_UNLOCKED("star"a->a_"arg", \""uname" "pos" ("arg")\");");
# Add assertions for locking
if (lockdata[name, arg, pos] == "L")
printc(ind"ASSERT_VOP_LOCKED(" star "a->a_"arg", \""uname" "pos" ("arg")\");");
else if (lockdata[name, arg, pos] == "U")
printc(ind"ASSERT_VOP_UNLOCKED(" star "a->a_"arg", \""uname" "pos" ("arg")\");");
else if (lockdata[name, arg, pos] == "E")
printc(ind"ASSERT_VOP_ELOCKED(" star "a->a_"arg", \""uname" "pos" ("arg")\");");
else if (0) {
# XXX More checks!
}
}
}
function add_debugpre(name)
{
if (lockdata[name, "debugpre"]) {
printc("#ifdef INVARIANTS");
printc("\t"lockdata[name, "debugpre"]"(a);");
printc("#endif");
}
}
function add_debugpost(name)
{
if (lockdata[name, "debugpost"]) {
printc("#ifdef INVARIANTS");
printc("\t"lockdata[name, "debugpost"]"(a, rc);");
printc("#endif");
}
}
function add_pre(name)
{
if (lockdata[name, "pre"]) {
printc("\t"lockdata[name, "pre"]"(a);");
}
}
function add_post(name)
{
if (lockdata[name, "post"]) {
printc("\t"lockdata[name, "post"]"(a, rc);");
}
}
function can_inline(name)
{
if (lockdata[name, "pre"])
return 0;
if (lockdata[name, "post"])
return 0;
return 1;
}
function find_arg_with_type (type)
{
for (jj = 0; jj < numargs; jj++) {
if (types[jj] == type) {
return "VOPARG_OFFSETOF(struct " \
name "_args,a_" args[jj] ")";
}
}
return "VDESC_NO_OFFSET";
}
BEGIN{
# Process the command line
for (i = 1; i < ARGC; i++) {
arg = ARGV[i];
if (arg !~ /^-[chpq]+$/ && arg !~ /\.src$/)
usage();
if (arg ~ /^-.*c/)
cfile = "vnode_if.c";
if (arg ~ /^-.*h/)
hfile = "vnode_if.h";
if (arg ~ /^-.*p/)
pfile = "vnode_if_newproto.h";
if (arg ~ /^-.*q/)
qfile = "vnode_if_typedef.h";
if (arg ~ /\.src$/)
srcfile = arg;
}
ARGC = 1;
if (!cfile && !hfile && !pfile && !qfile)
exit 0;
if (!srcfile)
usage();
# Avoid a literal generated file tag here.
generated = "@" "generated";
common_head = \
"/*\n" \
" * This file is " generated " automatically.\n" \
" * Do not modify anything in here by hand.\n" \
" */\n" \
"\n";
if (pfile) {
printp(common_head)
printp("struct vop_vector {")
printp("\tstruct vop_vector\t*vop_default;")
printp("\tvop_bypass_t\t*vop_bypass;")
}
if (qfile) {
printq(common_head)
}
if (hfile) {
printh(common_head "extern struct vnodeop_desc vop_default_desc;");
printh("#include \"vnode_if_typedef.h\"")
printh("#include \"vnode_if_newproto.h\"")
}
if (cfile) {
printc(common_head \
"#include <sys/param.h>\n" \
"#include <sys/event.h>\n" \
"#include <sys/inotify.h>\n" \
"#include <sys/kernel.h>\n" \
"#include <sys/mount.h>\n" \
"#include <sys/sdt.h>\n" \
"#include <sys/signalvar.h>\n" \
"#include <sys/systm.h>\n" \
"#include <sys/vnode.h>\n" \
"\n" \
"SDT_PROVIDER_DECLARE(vfs);\n" \
"\n" \
"struct vnodeop_desc vop_default_desc = {\n" \
" \"default\",\n" \
" 0,\n" \
" 0,\n" \
" (vop_bypass_t *)vop_panic,\n" \
" NULL,\n" \
" VDESC_NO_OFFSET,\n" \
" VDESC_NO_OFFSET,\n" \
" VDESC_NO_OFFSET,\n" \
" VDESC_NO_OFFSET,\n" \
"};\n");
}
while ((getline < srcfile) > 0) {
fnr++;
if (NF == 0)
continue;
if ($1 ~ /^%%/) {
if (NF != 6 ||
$2 !~ /^[a-z_]+$/ || $3 !~ /^[a-z]+$/ ||
$4 !~ /^.$/ || $5 !~ /^.$/ || $6 !~ /^.$/) {
die("Invalid %s construction", "%%");
continue;
}
lockdata["vop_" $2, $3, "Entry"] = $4;
lockdata["vop_" $2, $3, "OK"] = $5;
lockdata["vop_" $2, $3, "Error"] = $6;
continue;
}
if ($1 ~ /^%!/) {
if (NF != 4 ||
($3 != "pre" && $3 != "post" &&
$3 != "debugpre" && $3 != "debugpost")) {
die("Invalid %s construction", "%!");
continue;
}
lockdata["vop_" $2, $3] = $4;
continue;
}
if ($1 ~ /^#/)
continue;
# Get the function name.
name = $1;
uname = toupper(name);
# Get the function arguments.
for (numargs = 0; ; ++numargs) {
if ((getline < srcfile) <= 0) {
die("Unable to read through the arguments for \"%s\"",
name);
}
fnr++;
if ($1 ~ /^\};/)
break;
# Delete comments, if any.
gsub (/\/\*.*\*\//, "");
# Condense whitespace and delete leading/trailing space.
gsub(/[[:space:]]+/, " ");
sub(/^ /, "");
sub(/ $/, "");
# Pick off direction.
if ($1 != "INOUT" && $1 != "IN" && $1 != "OUT")
die("No IN/OUT direction for \"%s\".", $0);
dirs[numargs] = $1;
sub(/^[A-Z]* /, "");
if ((reles[numargs] = $1) == "WILLRELE")
sub(/^[A-Z]* /, "");
else
reles[numargs] = "WONTRELE";
# kill trailing ;
if (sub(/;$/, "") < 1)
die("Missing end-of-line ; in \"%s\".", $0);
# pick off variable name
if ((argp = match($0, /[A-Za-z0-9_]+$/)) < 1)
die("Missing var name \"a_foo\" in \"%s\".", $0);
args[numargs] = substr($0, argp);
$0 = substr($0, 1, argp - 1);
# what is left must be type
# remove trailing space (if any)
sub(/ $/, "");
types[numargs] = $0;
}
if (numargs > 4)
ctrargs = 4;
else
ctrargs = numargs;
ctrstr = ctrargs "(KTR_VOP, \"VOP\", \"" uname "\", (uintptr_t)a,\n\t ";
ctrstr = ctrstr "\"" args[0] ":0x%jX\", (uintptr_t)a->a_" args[0];
for (i = 1; i < ctrargs; ++i)
ctrstr = ctrstr ", \"" args[i] ":0x%jX\", a->a_" args[i];
ctrstr = ctrstr ");";
if (pfile) {
printp("\t"name"_t\t*"name";")
}
if (qfile) {
printq("struct "name"_args;")
printq("typedef int "name"_t(struct "name"_args *);\n")
}
if (hfile) {
# Print out the vop_F_args structure.
printh("struct "name"_args {\n\tstruct vop_generic_args a_gen;");
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 prototypes.
printh("int " uname "_AP(struct " name "_args *);");
printh("int " uname "_APV(const struct vop_vector *vop, 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("{");
printh("\tstruct " name "_args a;");
printh("");
printh("\ta.a_gen.a_desc = &" name "_desc;");
for (i = 0; i < numargs; ++i)
printh("\ta.a_" args[i] " = " args[i] ";");
if (can_inline(name)) {
printh("\n#if !defined(INVARIANTS) && !defined(KTR)");
printh("\tif (!SDT_PROBES_ENABLED())");
printh("\t\treturn (" args[0]"->v_op->"name"(&a));");
printh("\telse");
printh("\t\treturn (" uname "_APV("args[0]"->v_op, &a));");
printh("#else");
}
printh("\treturn (" uname "_APV("args[0]"->v_op, &a));");
if (can_inline(name))
printh("#endif");
printh("}");
printh("");
}
if (cfile) {
funcarr[name] = 1;
# Print out the vop_F_vp_offsets structure. This all depends
# on naming conventions and nothing else.
printc("static int " name "_vp_offsets[] = {");
# as a side effect, figure out the releflags
releflags = "";
vpnum = 0;
for (i = 0; i < numargs; i++) {
if (types[i] == "struct vnode *") {
printc("\tVOPARG_OFFSETOF(struct " name \
"_args,a_" args[i] "),");
if (reles[i] == "WILLRELE") {
releflags = releflags \
"|VDESC_VP" vpnum "_WILLRELE";
}
vpnum++;
}
}
sub(/^\|/, "", releflags);
printc("\tVDESC_NO_OFFSET");
printc("};");
printc("\n");
printc("SDT_PROBE_DEFINE2(vfs, vop, " name ", entry, \"struct vnode *\", \"struct " name "_args *\");\n");
printc("SDT_PROBE_DEFINE3(vfs, vop, " name ", return, \"struct vnode *\", \"struct " name "_args *\", \"int\");\n");
# Print out function.
printc("\nint\n" uname "_AP(struct " name "_args *a)");
printc("{");
printc("");
printc("\treturn(" uname "_APV(a->a_" args[0] "->v_op, a));");
printc("}");
printc("\nint\n" uname "_APV(const struct vop_vector *vop, struct " name "_args *a)");
printc("{");
printc("\tint rc;");
printc("");
printc("\tVNASSERT(a->a_gen.a_desc == &" name "_desc, a->a_" args[0]",");
printc("\t (\"Wrong a_desc in " name "(%p, %p)\", a->a_" args[0]", a));");
printc("\tVNASSERT(vop != NULL, a->a_" args[0]", (\"No "name"(%p, %p)\", a->a_" args[0]", a));")
printc("\tKTR_START" ctrstr);
add_debugpre(name);
add_pre(name);
for (i = 0; i < numargs; ++i)
add_debug_code(name, args[i], "Entry", "\t");
printc("\tSDT_PROBE2(vfs, vop, " name ", entry, a->a_" args[0] ", a);");
printc("\trc = vop->"name"(a);")
printc("\tSDT_PROBE3(vfs, vop, " name ", return, a->a_" args[0] ", a, rc);");
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_post(name);
add_debugpost(name);
printc("\tKTR_STOP" ctrstr);
printc("\treturn (rc);");
printc("}\n");
# Print out the vnodeop_desc structure.
printc("struct vnodeop_desc " name "_desc = {");
# printable name
printc("\t\"" name "\",");
# flags
vppwillrele = "";
for (i = 0; i < numargs; i++) {
if (types[i] == "struct vnode **" && \
reles[i] == "WILLRELE") {
vppwillrele = "|VDESC_VPP_WILLRELE";
}
}
if (!releflags)
releflags = "0";
printc("\t" releflags vppwillrele ",");
# index in struct vop_vector
printc("\t__offsetof(struct vop_vector, " name "),");
# function to call
printc("\t(vop_bypass_t *)" uname "_AP,");
# vp offsets
printc("\t" name "_vp_offsets,");
# vpp (if any)
printc("\t" find_arg_with_type("struct vnode **") ",");
# cred (if any)
printc("\t" find_arg_with_type("struct ucred *") ",");
# thread (if any)
printc("\t" find_arg_with_type("struct thread *") ",");
# componentname
printc("\t" find_arg_with_type("struct componentname *") ",");
# transport layer information
printc("};\n");
}
}
if (cfile) {
printc("void");
printc("vfs_vector_op_register(struct vop_vector *orig_vop)");
printc("{");
printc("\tstruct vop_vector *vop;");
printc("");
printc("\tif (orig_vop->registered)");
printc("\t\tpanic(\"%s: vop_vector %p already registered\",")
printc("\t\t __func__, orig_vop);");
printc("");
printc("\tcache_vop_vector_register(orig_vop);");
printc("");
for (name in funcarr) {
printc("\tvop = orig_vop;");
printc("\twhile (vop != NULL && \\");
printc("\t vop->"name" == NULL && vop->vop_bypass == NULL)")
printc("\t\tvop = vop->vop_default;")
printc("\tif (vop != NULL)");
printc("\t\torig_vop->"name" = vop->"name";");
printc("");
}
printc("\tvop = orig_vop;");
printc("\twhile (vop != NULL && vop->vop_bypass == NULL)")
printc("\t\tvop = vop->vop_default;")
printc("\tif (vop != NULL)");
printc("\t\torig_vop->vop_bypass = vop->vop_bypass;");
printc("");
for (name in funcarr) {
printc("\tif (orig_vop->"name" == NULL)");
printc("\t\torig_vop->"name" = (void *)orig_vop->vop_bypass;");
}
printc("");
printc("\torig_vop->registered = true;");
printc("}")
}
if (hfile) {
printh("void vfs_vector_op_register(struct vop_vector *orig_vop);");
}
if (pfile) {
printp("\tbool\tregistered;")
printp("};")
}
if (hfile)
close(hfile);
if (cfile)
close(cfile);
if (pfile)
close(pfile);
close(srcfile);
exit 0;
}