Nuke data.S, since we do have a custom linker script.

This commit is contained in:
Austin Clements 2011-09-02 14:51:55 -04:00
parent ce6dd9de27
commit dd4438b4fe
4 changed files with 13 additions and 31 deletions

View file

@ -109,8 +109,8 @@ initcode: initcode.S
$(OBJCOPY) -S -O binary initcode.out initcode
$(OBJDUMP) -S initcode.o > initcode.asm
kernel: $(OBJS) entry.o data.o entryother initcode
$(LD) $(LDFLAGS) -T kernel.ld -e entry -o kernel entry.o data.o $(OBJS) -b binary initcode entryother
kernel: $(OBJS) entry.o entryother initcode
$(LD) $(LDFLAGS) -T kernel.ld -e entry -o kernel entry.o $(OBJS) -b binary initcode entryother
$(OBJDUMP) -S kernel > kernel.asm
$(OBJDUMP) -t kernel | sed '1,/SYMBOL TABLE/d; s/ .* / /; /^$$/d' > kernel.sym
@ -121,8 +121,8 @@ kernel: $(OBJS) entry.o data.o entryother initcode
# great for testing the kernel on real hardware without
# needing a scratch disk.
MEMFSOBJS = $(filter-out ide.o,$(OBJS)) memide.o
kernelmemfs: $(MEMFSOBJS) entry.o data.o entryother initcode fs.img
$(LD) $(LDFLAGS) -Ttext 0x100000 -e main -o kernelmemfs entry.o data.o $(MEMFSOBJS) -b binary initcode entryother fs.img
kernelmemfs: $(MEMFSOBJS) entry.o entryother initcode fs.img
$(LD) $(LDFLAGS) -Ttext 0x100000 -e main -o kernelmemfs entry.o $(MEMFSOBJS) -b binary initcode entryother fs.img
$(OBJDUMP) -S kernelmemfs > kernelmemfs.asm
$(OBJDUMP) -t kernelmemfs | sed '1,/SYMBOL TABLE/d; s/ .* / /; /^$$/d' > kernelmemfs.sym

26
data.S
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@ -1,26 +0,0 @@
// The kernel layout is:
//
// text
// rodata
// data
// bss
//
// Conventionally, Unix linkers provide pseudo-symbols
// etext, edata, and end, at the end of the text, data, and bss.
// For the kernel mapping, we need the address at the beginning
// of the data section, but that's not one of the conventional
// symbols, because the convention started before there was a
// read-only rodata section between text and data.
//
// To get the address of the data section, we define a symbol
// named data and make sure this is the first object passed to
// the linker, so that it will be the first symbol in the data section.
//
// Alternative approaches would be to parse our own ELF header
// or to write a linker script, but this is simplest.
.data
.align 4096
.globl data
data:
.word 1

View file

@ -41,6 +41,14 @@ SECTIONS
/* Adjust the address for the data segment to the next page */
. = ALIGN(0x1000);
/* Conventionally, Unix linkers provide pseudo-symbols
* etext, edata, and end, at the end of the text, data, and bss.
* For the kernel mapping, we need the address at the beginning
* of the data section, but that's not one of the conventional
* symbols, because the convention started before there was a
* read-only rodata section between text and data. */
PROVIDE(data = .);
/* The data segment */
.data : {
*(.data)

2
vm.c
View file

@ -7,7 +7,7 @@
#include "proc.h"
#include "elf.h"
extern char data[]; // defined in data.S
extern char data[]; // defined by kernel.ld
pde_t *kpgdir; // for use in scheduler()
struct segdesc gdt[NSEGS];