initial commit

Makefile

@@ -0,0 +1,249 @@
+OBJS = \
+	bio.o\
+	console.o\
+	exec.o\
+	file.o\
+	fs.o\
+	ide.o\
+	ioapic.o\
+	kalloc.o\
+	kbd.o\
+	lapic.o\
+	main.o\
+	mp.o\
+	picirq.o\
+	pipe.o\
+	proc.o\
+	spinlock.o\
+	string.o\
+	swtch.o\
+	syscall.o\
+	sysfile.o\
+	sysproc.o\
+	timer.o\
+	trapasm.o\
+	trap.o\
+	uart.o\
+	vectors.o\
+	vm.o\
+
+UPROGS=\
+	_cat\
+	_echo\
+	_forktest\
+	_grep\
+	_init\
+	_kill\
+	_ln\
+	_ls\
+	_mkdir\
+	_rm\
+	_sh\
+	_stressfs\
+	_usertests\
+	_wc\
+	_zombie\
+
+# Cross-compiling (e.g., on Mac OS X)
+#TOOLPREFIX = i386-jos-elf-
+
+# Using native tools (e.g., on X86 Linux)
+#TOOLPREFIX = 
+
+# Try to infer the correct TOOLPREFIX if not set
+ifndef TOOLPREFIX
+TOOLPREFIX := $(shell if i386-jos-elf-objdump -i 2>&1 | grep '^elf32-i386$$' >/dev/null 2>&1; \
+	then echo 'i386-jos-elf-'; \
+	elif objdump -i 2>&1 | grep 'elf32-i386' >/dev/null 2>&1; \
+	then echo ''; \
+	else echo "***" 1>&2; \
+	echo "*** Error: Couldn't find an i386-*-elf version of GCC/binutils." 1>&2; \
+	echo "*** Is the directory with i386-jos-elf-gcc in your PATH?" 1>&2; \
+	echo "*** If your i386-*-elf toolchain is installed with a command" 1>&2; \
+	echo "*** prefix other than 'i386-jos-elf-', set your TOOLPREFIX" 1>&2; \
+	echo "*** environment variable to that prefix and run 'make' again." 1>&2; \
+	echo "*** To turn off this error, run 'gmake TOOLPREFIX= ...'." 1>&2; \
+	echo "***" 1>&2; exit 1; fi)
+endif
+
+# If the makefile can't find QEMU, specify its path here
+# QEMU = ~cs537-1/ta/tools/qemu
+
+# Try to infer the correct QEMU
+ifndef QEMU
+QEMU = $(shell if which qemu > /dev/null; \
+	then echo qemu; exit; \
+	else \
+	qemu=/Applications/Q.app/Contents/MacOS/i386-softmmu.app/Contents/MacOS/i386-softmmu; \
+	if test -x $$qemu; then echo $$qemu; exit; fi; fi; \
+	echo "***" 1>&2; \
+	echo "*** Error: Couldn't find a working QEMU executable." 1>&2; \
+	echo "*** Is the directory containing the qemu binary in your PATH" 1>&2; \
+	echo "*** or have you tried setting the QEMU variable in Makefile?" 1>&2; \
+	echo "***" 1>&2; exit 1)
+endif
+
+CC = $(TOOLPREFIX)gcc
+AS = $(TOOLPREFIX)gas
+LD = $(TOOLPREFIX)ld
+OBJCOPY = $(TOOLPREFIX)objcopy
+OBJDUMP = $(TOOLPREFIX)objdump
+CFLAGS = -fno-pic -static -fno-builtin -fno-strict-aliasing -O2 -Wall -ggdb -m32 -Werror
+CFLAGS += $(shell $(CC) -fno-stack-protector -E -x c /dev/null >/dev/null 2>&1 && echo -fno-stack-protector)
+ASFLAGS = -m32 -gdwarf-2
+# FreeBSD ld wants ``elf_i386_fbsd''
+LDFLAGS += -m $(shell $(LD) -V | grep elf_i386 2>/dev/null)
+MAKEDEPEND = gcc -MM -o $*.d $<
+
+all: bootblock kernel $(UPROGS)
+
+CSRCS = $(wildcard *.c)
+SSRCS = bootasm.S data.S multiboot.S  trapasm.S bootother.S initcode.S swtch.S usys.S
+CDEPS = $(CSRCS:.c=.d)
+SDEPS = $(SSRCS:.S=.d)
+
+%.d: %.c
+	@echo $(CC) -MM $(CFLAGS) $<
+	@$(SHELL) -ec '$(CC) -MM $(CPPFLAGS) $< \
+   	| sed '\''s/\($*\)\.o[ :]*/\1.o $@ : /g'\'' > $@; [ -s $@ ] || rm -f $@'
+
+%.d: %.S
+	@echo $(CC) -MM $(CFLAGS) $<
+	@$(SHELL) -ec '$(CC) -MM $(CPPFLAGS) $< \
+   	| sed '\''s/\($*\)\.o[ :]*/\1.o $@ : /g'\'' > $@; [ -s $@ ] || rm -f $@'
+
+-include $(CDEPS) $(SDEPS)
+
+xv6.img: bootblock kernel
+	dd if=/dev/zero of=xv6.img count=10000
+	dd if=bootblock of=xv6.img conv=notrunc
+	dd if=kernel of=xv6.img seek=1 conv=notrunc
+
+xv6memfs.img: bootblock kernelmemfs
+	dd if=/dev/zero of=xv6memfs.img count=10000
+	dd if=bootblock of=xv6memfs.img conv=notrunc
+	dd if=kernelmemfs of=xv6memfs.img seek=1 conv=notrunc
+
+bootblock: bootasm.S bootmain.c
+	$(CC) $(CFLAGS) -fno-pic -O -nostdinc -I. -c bootmain.c
+	$(CC) $(CFLAGS) -fno-pic -nostdinc -I. -c bootasm.S
+	$(LD) $(LDFLAGS) -N -e start -Ttext 0x7C00 -o bootblock.o bootasm.o bootmain.o
+	$(OBJDUMP) -S bootblock.o > bootblock.asm
+	$(OBJCOPY) -S -O binary -j .text bootblock.o bootblock
+	./sign.pl bootblock
+
+bootother: bootother.S
+	$(CC) $(CFLAGS) -nostdinc -I. -c bootother.S
+	$(LD) $(LDFLAGS) -N -e start -Ttext 0x7000 -o bootother.out bootother.o
+	$(OBJCOPY) -S -O binary bootother.out bootother
+	$(OBJDUMP) -S bootother.o > bootother.asm
+
+initcode: initcode.S
+	$(CC) $(CFLAGS) -nostdinc -I. -c initcode.S
+	$(LD) $(LDFLAGS) -N -e start -Ttext 0 -o initcode.out initcode.o
+	$(OBJCOPY) -S -O binary initcode.out initcode
+	$(OBJDUMP) -S initcode.o > initcode.asm
+
+kernel: $(OBJS) multiboot.o data.o bootother initcode
+	$(LD) $(LDFLAGS) -Ttext 0x100000 -e main -o kernel multiboot.o data.o $(OBJS) -b binary initcode bootother
+	$(OBJDUMP) -S kernel > kernel.asm
+	$(OBJDUMP) -t kernel | sed '1,/SYMBOL TABLE/d; s/ .* / /; /^$$/d' > kernel.sym
+
+# kernelmemfs is a copy of kernel that maintains the
+# disk image in memory instead of writing to a disk.
+# This is not so useful for testing persistent storage or
+# exploring disk buffering implementations, but it is
+# great for testing the kernel on real hardware without
+# needing a scratch disk.
+MEMFSOBJS = $(filter-out ide.o,$(OBJS)) memide.o
+kernelmemfs: $(MEMFSOBJS) multiboot.o data.o bootother initcode fs.img
+	$(LD) $(LDFLAGS) -Ttext 0x100000 -e main -o kernelmemfs multiboot.o data.o $(MEMFSOBJS) -b binary initcode bootother fs.img
+	$(OBJDUMP) -S kernelmemfs > kernelmemfs.asm
+	$(OBJDUMP) -t kernelmemfs | sed '1,/SYMBOL TABLE/d; s/ .* / /; /^$$/d' > kernelmemfs.sym
+
+tags: $(OBJS) bootother.S _init
+	etags *.S *.c
+
+vectors.S: vectors.pl
+	perl vectors.pl > vectors.S
+
+ULIB = ulib.o usys.o printf.o umalloc.o
+
+_%: %.o $(ULIB)
+	$(LD) $(LDFLAGS) -N -e main -Ttext 0 -o $@ $^
+	$(OBJDUMP) -S $@ > $*.asm
+	$(OBJDUMP) -t $@ | sed '1,/SYMBOL TABLE/d; s/ .* / /; /^$$/d' > $*.sym
+
+_forktest: forktest.o $(ULIB)
+	# forktest has less library code linked in - needs to be small
+	# in order to be able to max out the proc table.
+	$(LD) $(LDFLAGS) -N -e main -Ttext 0 -o _forktest forktest.o ulib.o usys.o
+	$(OBJDUMP) -S _forktest > forktest.asm
+
+mkfs: mkfs.c fs.h
+	gcc -m32 -Werror -Wall -o mkfs mkfs.c
+
+fs.img: mkfs README $(UPROGS)
+	./mkfs fs.img README $(UPROGS)
+
+#-include *.d
+
+clean: 
+	rm -f *.tex *.dvi *.idx *.aux *.log *.ind *.ilg \
+	*.o *.d *.asm *.sym vectors.S parport.out \
+	bootblock kernel xv6.img fs.img mkfs \
+	initcode.out initcode bootother.out bootother \
+	xv6.tar.gz .gdbinit \
+	$(UPROGS)
+
+# make a printout
+FILES = $(shell grep -v '^\#' runoff.list)
+PRINT = runoff.list runoff.spec $(FILES)
+
+xv6.pdf: $(PRINT)
+	./runoff
+	ls -l xv6.pdf
+
+print: xv6.pdf
+
+# run in emulators
+
+bochs : fs.img xv6.img
+	if [ ! -e .bochsrc ]; then ln -s dot-bochsrc .bochsrc; fi
+	bochs -q
+
+# try to generate a unique GDB port
+GDBPORT = $(shell expr `id -u` % 5000 + 25000)
+# QEMU's gdb stub command line changed in 0.11
+QEMUGDB = $(shell if $(QEMU) -help | grep -q '^-gdb'; \
+	then echo "-gdb tcp::$(GDBPORT)"; \
+	else echo "-s -p $(GDBPORT)"; fi)
+ifndef CPUS
+CPUS := 1
+endif
+QEMUOPTS = -hdb fs.img xv6.img -smp $(CPUS)
+
+qemu: fs.img xv6.img
+	$(QEMU) -serial mon:stdio $(QEMUOPTS)
+
+qemu-memfs: xv6memfs.img
+	$(QEMU) xv6memfs.img -smp $(CPUS)
+
+qemu-nox: fs.img xv6.img
+	$(QEMU) -nographic $(QEMUOPTS)
+
+.gdbinit: .gdbinit.tmpl
+	sed "s/localhost:1234/localhost:$(GDBPORT)/" < $^ > $@
+
+qemu-gdb: fs.img xv6.img .gdbinit
+	@echo "*** Now run 'gdb'." 1>&2
+	$(QEMU) -serial mon:stdio $(QEMUOPTS) -S $(QEMUGDB)
+
+qemu-nox-gdb: fs.img xv6.img .gdbinit
+	@echo "*** Now run 'gdb'." 1>&2
+	$(QEMU) -nographic $(QEMUOPTS) -S $(QEMUGDB)
+
+tarball: xv6.tar.gz
+
+xv6.tar.gz: clean
+	tar -czf $@ --exclude $@ .

README

@@ -0,0 +1,50 @@
+xv6 is a re-implementation of Dennis Ritchie's and Ken Thompson's Unix
+Version 6 (v6).  xv6 loosely follows the structure and style of v6,
+but is implemented for a modern x86-based multiprocessor using ANSI C.
+
+ACKNOWLEDGMENTS
+
+xv6 is inspired by John Lions's Commentary on UNIX 6th Edition (Peer
+to Peer Communications; ISBN: 1-57398-013-7; 1st edition (June 14,
+2000)). See also http://pdos.csail.mit.edu/6.828/2007/v6.html, which
+provides pointers to on-line resources for v6.
+
+xv6 borrows code from the following sources:
+    JOS (asm.h, elf.h, mmu.h, bootasm.S, ide.c, console.c, and others)
+    Plan 9 (bootother.S, mp.h, mp.c, lapic.c)
+    FreeBSD (ioapic.c)
+    NetBSD (console.c)
+
+The following people made contributions:
+    Russ Cox (context switching, locking)
+    Cliff Frey (MP)
+    Xiao Yu (MP)
+    Nickolai Zeldovich
+    Austin Clements
+
+In addition, we are grateful for the patches contributed by Greg
+Price, Yandong Mao, and Hitoshi Mitake.
+
+The code in the files that constitute xv6 is
+Copyright 2006-2007 Frans Kaashoek, Robert Morris, and Russ Cox.
+
+ERROR REPORTS
+
+If you spot errors or have suggestions for improvement, please send
+email to Frans Kaashoek and Robert Morris (kaashoek,rtm@csail.mit.edu). 
+
+BUILDING AND RUNNING XV6
+
+To build xv6 on an x86 ELF machine (like Linux or FreeBSD), run "make".
+On non-x86 or non-ELF machines (like OS X, even on x86), you will
+need to install a cross-compiler gcc suite capable of producing x86 ELF
+binaries.  See http://pdos.csail.mit.edu/6.828/2007/tools.html.
+Then run "make TOOLPREFIX=i386-jos-elf-".
+
+To run xv6, you can use Bochs or QEMU, both PC simulators.
+Bochs makes debugging easier, but QEMU is much faster. 
+To run in Bochs, run "make bochs" and then type "c" at the bochs prompt.
+To run in QEMU, run "make qemu".
+
+To create a typeset version of the code, run "make xv6.pdf".  This
+requires the "mpage" utility.  See http://www.mesa.nl/pub/mpage/.

asm.h

@@ -0,0 +1,21 @@
+//
+// assembler macros to create x86 segments
+//
+
+#define SEG_NULLASM                                             \
+        .word 0, 0;                                             \
+        .byte 0, 0, 0, 0
+
+// The 0xC0 means the limit is in 4096-byte units
+// and (for executable segments) 32-bit mode.
+#define SEG_ASM(type,base,lim)                                  \
+        .word (((lim) >> 12) & 0xffff), ((base) & 0xffff);      \
+        .byte (((base) >> 16) & 0xff), (0x90 | (type)),         \
+                (0xC0 | (((lim) >> 28) & 0xf)), (((base) >> 24) & 0xff)
+
+#define STA_X     0x8       // Executable segment
+#define STA_E     0x4       // Expand down (non-executable segments)
+#define STA_C     0x4       // Conforming code segment (executable only)
+#define STA_W     0x2       // Writeable (non-executable segments)
+#define STA_R     0x2       // Readable (executable segments)
+#define STA_A     0x1       // Accessed