Skip site navigation (1)Skip section navigation (2)
Date:      Thu, 13 Aug 2015 15:16:34 +0000 (UTC)
From:      Marcel Moolenaar <marcel@FreeBSD.org>
To:        src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org
Subject:   svn commit: r286727 - in head/sys: conf dev/md
Message-ID:  <201508131516.t7DFGYVS084845@repo.freebsd.org>

next in thread | raw e-mail | index | archive | help
Author: marcel
Date: Thu Aug 13 15:16:34 2015
New Revision: 286727
URL: https://svnweb.freebsd.org/changeset/base/286727

Log:
  Change md(4) to use weak symbols as start, end and size for the embedded
  root disk. The embedded image is linked into the kernel in the .mfs
  section.
  
  Add rules and variables to kern.pre.mk and kern.post.mk that handle the
  linking of the image. First objcopy is used to generate an object file.
  Then, the object file is linked into the kernel.
  
  Submitted by:	Steve Kiernan <stevek@juniper.net>
  Reviewed by:	brooks@
  Obtained from: Juniper Networks, Inc.
  Differential Revision:	https://reviews.freebsd.org/D2903

Modified:
  head/sys/conf/Makefile.arm
  head/sys/conf/kern.post.mk
  head/sys/conf/kern.pre.mk
  head/sys/dev/md/md.c

Modified: head/sys/conf/Makefile.arm
==============================================================================
--- head/sys/conf/Makefile.arm	Thu Aug 13 14:53:29 2015	(r286726)
+++ head/sys/conf/Makefile.arm	Thu Aug 13 15:16:34 2015	(r286727)
@@ -66,10 +66,6 @@ SYSTEM_LD_TAIL +=;sed s/" + SIZEOF_HEADE
 		${KERNEL_KO}.bin; \
 		rm ${FULLKERNEL}.noheader
 
-.if defined(MFS_IMAGE)
-SYSTEM_LD_TAIL += ;sh ${S}/tools/embed_mfs.sh ${KERNEL_KO}.bin ${MFS_IMAGE};
-.endif
-
 FILES_CPU_FUNC = \
 	$S/$M/$M/cpufunc_asm_arm9.S \
 	$S/$M/$M/cpufunc_asm_arm10.S \

Modified: head/sys/conf/kern.post.mk
==============================================================================
--- head/sys/conf/kern.post.mk	Thu Aug 13 14:53:29 2015	(r286726)
+++ head/sys/conf/kern.post.mk	Thu Aug 13 15:16:34 2015	(r286727)
@@ -121,7 +121,7 @@ gdbinit:
 .endif
 .endif
 
-${FULLKERNEL}: ${SYSTEM_DEP} vers.o ${MFS_IMAGE}
+${FULLKERNEL}: ${SYSTEM_DEP} vers.o
 	@rm -f ${.TARGET}
 	@echo linking ${.TARGET}
 	${SYSTEM_LD}
@@ -133,9 +133,6 @@ ${FULLKERNEL}: ${SYSTEM_DEP} vers.o ${MF
 	${OBJCOPY} --strip-debug ${.TARGET}
 .endif
 	${SYSTEM_LD_TAIL}
-.if defined(MFS_IMAGE)
-	sh ${S}/tools/embed_mfs.sh ${FULLKERNEL} ${MFS_IMAGE}
-.endif
 
 .if !exists(${.OBJDIR}/.depend)
 ${SYSTEM_OBJS}: assym.s vnode_if.h ${BEFORE_DEPEND:M*.h} ${MFILES:T:S/.m$/.h/}
@@ -301,6 +298,27 @@ vnode_if_newproto.h:
 vnode_if_typedef.h:
 	${AWK} -f $S/tools/vnode_if.awk $S/kern/vnode_if.src -q
 
+.if ${MFS_IMAGE:Uno} != "no"
+# Generate an object file from the file system image to embed in the kernel
+# via linking. Make sure the contents are in the mfs section and rename the
+# start/end/size variables to __start_mfs, __stop_mfs, and mfs_size,
+# respectively.
+embedfs_${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}
+.endif
+
 # XXX strictly, everything depends on Makefile because changes to ${PROF}
 # only appear there, but we don't handle that.
 

Modified: head/sys/conf/kern.pre.mk
==============================================================================
--- head/sys/conf/kern.pre.mk	Thu Aug 13 14:53:29 2015	(r286726)
+++ head/sys/conf/kern.pre.mk	Thu Aug 13 15:16:34 2015	(r286727)
@@ -191,6 +191,9 @@ SYSTEM_DEP= Makefile ${SYSTEM_OBJS}
 SYSTEM_OBJS= locore.o ${MDOBJS} ${OBJS}
 SYSTEM_OBJS+= ${SYSTEM_CFILES:.c=.o}
 SYSTEM_OBJS+= hack.So
+.if ${MFS_IMAGE:Uno} != "no"
+SYSTEM_OBJS+= embedfs_${MFS_IMAGE:T:R}.o
+.endif
 SYSTEM_LD= @${LD} -Bdynamic -T ${LDSCRIPT} ${_LDFLAGS} --no-warn-mismatch \
 	--warn-common --export-dynamic --dynamic-linker /red/herring \
 	-o ${.TARGET} -X ${SYSTEM_OBJS} vers.o
@@ -222,6 +225,32 @@ MKMODULESENV+=	DEBUG_FLAGS="${DEBUG}"
 .endif
 MKMODULESENV+=	_MPATH="${_MPATH}"
 
+# Architecture and output format arguments for objdump to convert image to
+# object file
+.if ${MFS_IMAGE:Uno} != "no"
+
+.if !defined(EMBEDFS_FORMAT.${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.mips?=		elf32-tradbigmips
+EMBEDFS_FORMAT.mipsel?=		elf32-tradlittlemips
+EMBEDFS_FORMAT.mips64?=		elf64-tradbigmips
+EMBEDFS_FORMAT.mips64el?=	elf64-tradlittlemips
+.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

Modified: head/sys/dev/md/md.c
==============================================================================
--- head/sys/dev/md/md.c	Thu Aug 13 14:53:29 2015	(r286726)
+++ head/sys/dev/md/md.c	Thu Aug 13 15:16:34 2015	(r286727)
@@ -122,9 +122,12 @@ SYSCTL_INT(_vm, OID_AUTO, md_malloc_wait
 #define	MD_ROOT_FSTYPE	"ufs"
 #endif
 
-#if defined(MD_ROOT) && defined(MD_ROOT_SIZE)
+#if defined(MD_ROOT)
 /*
  * Preloaded image gets put here.
+ */
+#if defined(MD_ROOT_SIZE)
+/*
  * Applications that patch the object with the image can determine
  * the size looking at the start and end markers (strings),
  * so we want them contiguous.
@@ -136,6 +139,14 @@ static struct {
 	.start = "MFS Filesystem goes here",
 	.end = "MFS Filesystem had better STOP here",
 };
+const int mfs_root_size = sizeof(mfs_root.start);
+#else
+extern volatile u_char __weak_symbol mfs_root;
+extern volatile u_char __weak_symbol mfs_root_end;
+__GLOBL(mfs_root);
+__GLOBL(mfs_root_end);
+#define mfs_root_size ((uintptr_t)(&mfs_root_end - &mfs_root))
+#endif
 #endif
 
 static g_init_t g_md_init;
@@ -1553,6 +1564,9 @@ md_preloaded(u_char *image, size_t lengt
 	if (name != NULL) {
 		printf("%s%d: Preloaded image <%s> %zd bytes at %p\n",
 		    MD_NAME, sc->unit, name, length, image);
+	} else {
+		printf("%s%d: Embedded image %zd bytes as %p\n",
+		    MD_NAME, sc->unit, length, image);
 	}
 }
 
@@ -1572,10 +1586,13 @@ g_md_init(struct g_class *mp __unused)
 	sx_init(&md_sx, "MD config lock");
 	g_topology_unlock();
 	md_uh = new_unrhdr(0, INT_MAX, NULL);
-#ifdef MD_ROOT_SIZE
-	sx_xlock(&md_sx);
-	md_preloaded(mfs_root.start, sizeof(mfs_root.start), NULL);
-	sx_xunlock(&md_sx);
+#ifdef MD_ROOT
+	if (mfs_root_size != 0) {
+		sx_xlock(&md_sx);
+		md_preloaded(__DEVOLATILE(u_char *, &mfs_root), mfs_root_size,
+		    NULL);
+		sx_xunlock(&md_sx);
+	}
 #endif
 	/* XXX: are preload_* static or do they need Giant ? */
 	while ((mod = preload_search_next_name(mod)) != NULL) {



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?201508131516.t7DFGYVS084845>