svn commit: r366897 - in head/sys: conf dev/md

[John Baldwin]

Author: jhb
Date: Tue Oct 20 16:48:45 2020
New Revision: 366897
URL: https://svnweb.freebsd.org/changeset/base/366897

Log:
  Use a template assembly file to generate the embedded MFS.
  
  This uses the .incbin directive to pull in the MFS image contents.
  Using assembly directly ensures that symbols can be defined with the
  name and properties (such as .size) desired without having to rename
  symbols, etc. via a second objcopy invocation.  Since it is compiled
  by the C compiler driver, it also avoids the need for all of the
  EMBEDFS* make variables.
  
  Suggested by:	jrtc27
  Reviewed by:	kib, markj
  Obtained from:	CheriBSD
  MFC after:	2 weeks
  Sponsored by:	DARPA
  Differential Revision:	https://reviews.freebsd.org/D26781

Added:
  head/sys/dev/md/embedfs.S   (contents, props changed)
Modified:
  head/sys/conf/kern.post.mk
  head/sys/conf/kern.pre.mk

Modified: head/sys/conf/kern.post.mk
==============================================================================
--- head/sys/conf/kern.post.mk	Tue Oct 20 13:15:26 2020	(r366896)
+++ head/sys/conf/kern.post.mk	Tue Oct 20 16:48:45 2020	(r366897)
@@ -457,24 +457,9 @@ vnode_if_typedef.h:
 
 .if ${MFS_IMAGE:Uno} != "no"
 .if empty(MD_ROOT_SIZE_CONFIGURED)
-# Generate an object file from the file system image to embed in the kernel
-# via linking. Make sure the contents are in the mfs section and rename the
-# start/end/size variables to __start_mfs, __stop_mfs, and mfs_size,
-# respectively.
-embedfs_${MFS_IMAGE:T:R}.o: ${MFS_IMAGE}
-	${OBJCOPY} --input-target binary \
-	    --output-target ${EMBEDFS_FORMAT.${MACHINE_ARCH}} \
-	    --binary-architecture ${EMBEDFS_ARCH.${MACHINE_ARCH}} \
-	    ${MFS_IMAGE} ${.TARGET}
-	${OBJCOPY} \
-	    --rename-section .data=mfs,contents,alloc,load,readonly,data \
-	    --redefine-sym \
-		_binary_${MFS_IMAGE:C,[^[:alnum:]],_,g}_size=__mfs_root_size \
-	    --redefine-sym \
-		_binary_${MFS_IMAGE:C,[^[:alnum:]],_,g}_start=mfs_root \
-	    --redefine-sym \
-		_binary_${MFS_IMAGE:C,[^[:alnum:]],_,g}_end=mfs_root_end \
-	    ${.TARGET}
+embedfs_${MFS_IMAGE:T:R}.o: ${MFS_IMAGE} $S/dev/md/embedfs.S
+	${CC} ${CFLAGS} ${ACFLAGS} -DMFS_IMAGE="${MFS_IMAGE}" -c \
+	    $S/dev/md/embedfs.S -o ${.TARGET}
 .endif
 .endif
 

Modified: head/sys/conf/kern.pre.mk
==============================================================================
--- head/sys/conf/kern.pre.mk	Tue Oct 20 13:15:26 2020	(r366896)
+++ head/sys/conf/kern.pre.mk	Tue Oct 20 16:48:45 2020	(r366897)
@@ -358,37 +358,6 @@ MKMODULESENV+=	DEBUG_FLAGS="${DEBUG}"
 MKMODULESENV+=	__MPATH="${__MPATH}"
 .endif
 
-# Architecture and output format arguments for objcopy to convert image to
-# object file
-
-.if ${MFS_IMAGE:Uno} != "no"
-.if empty(MD_ROOT_SIZE_CONFIGURED)
-.if !defined(EMBEDFS_FORMAT.${MACHINE_ARCH})
-EMBEDFS_FORMAT.${MACHINE_ARCH}!= awk -F'"' '/OUTPUT_FORMAT/ {print $$2}' ${LDSCRIPT}
-.if empty(EMBEDFS_FORMAT.${MACHINE_ARCH})
-.undef EMBEDFS_FORMAT.${MACHINE_ARCH}
-.endif
-.endif
-
-.if !defined(EMBEDFS_ARCH.${MACHINE_ARCH})
-EMBEDFS_ARCH.${MACHINE_ARCH}!= sed -n '/OUTPUT_ARCH/s/.*(\(.*\)).*/\1/p' ${LDSCRIPT}
-.if empty(EMBEDFS_ARCH.${MACHINE_ARCH})
-.undef EMBEDFS_ARCH.${MACHINE_ARCH}
-.endif
-.endif
-
-EMBEDFS_FORMAT.arm?=		elf32-littlearm
-EMBEDFS_FORMAT.armv6?=		elf32-littlearm
-EMBEDFS_FORMAT.armv7?=		elf32-littlearm
-EMBEDFS_FORMAT.aarch64?=	elf64-littleaarch64
-EMBEDFS_FORMAT.mips?=		elf32-tradbigmips
-EMBEDFS_FORMAT.mipsel?=		elf32-tradlittlemips
-EMBEDFS_FORMAT.mips64?=		elf64-tradbigmips
-EMBEDFS_FORMAT.mips64el?=	elf64-tradlittlemips
-EMBEDFS_FORMAT.riscv64?=	elf64-littleriscv
-.endif
-.endif
-
 # Detect kernel config options that force stack frames to be turned on.
 DDB_ENABLED!=	grep DDB opt_ddb.h || true ; echo
 DTR_ENABLED!=	grep KDTRACE_FRAME opt_kdtrace.h || true ; echo

Added: head/sys/dev/md/embedfs.S
==============================================================================
--- /dev/null	00:00:00 1970	(empty, because file is newly added)
+++ head/sys/dev/md/embedfs.S	Tue Oct 20 16:48:45 2020	(r366897)
@@ -0,0 +1,46 @@
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (c) 2020 John Baldwin <jhb at FreeBSD.org>
+ *
+ * This software was developed by SRI International and the University of
+ * Cambridge Computer Laboratory (Department of Computer Science and
+ * Technology) under DARPA contract HR0011-18-C-0016 ("ECATS"), as part of the
+ * DARPA SSITH research programme.
+ *
+ * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
+ *
+ * $FreeBSD$
+ */
+
+#include <sys/cdefs.h>
+
+	.section mfs, "a", %progbits
+	.globl	mfs_root
+	.type	mfs_root, %object
+mfs_root:
+	.incbin	__XSTRING(MFS_IMAGE)
+	.size	mfs_root, . - mfs_root
+	.globl	mfs_root_end
+	.type	mfs_root_end, %object
+mfs_root_end:
+	.size	mfs_root_end, . - mfs_root_end