Chapter 2

Author: rcy17

Makefile

@@ -4,6 +4,7 @@ all: build_kernel
 LOG ?= error
 
 K = os
+U = user
 
 TOOLPREFIX = riscv64-unknown-elf-
 CC = $(TOOLPREFIX)gcc
@@ -14,8 +15,6 @@ OBJDUMP = $(TOOLPREFIX)objdump
 PY = python3
 GDB = $(TOOLPREFIX)gdb
 CP = cp
-MKDIR_P = mkdir -p
-
 BUILDDIR = build
 C_SRCS = $(wildcard $K/*.c)
 AS_SRCS = $(wildcard $K/*.S)
@@ -25,6 +24,10 @@ OBJS = $(C_OBJS) $(AS_OBJS)
 
 HEADER_DEP = $(addsuffix .d, $(basename $(C_OBJS)))
 
+ifeq (,$(findstring link_app.o,$(OBJS)))
+	AS_OBJS += $(BUILDDIR)/$K/link_app.o
+endif
+
 -include $(HEADER_DEP)
 
 CFLAGS = -Wall -Werror -O -fno-omit-frame-pointer -ggdb
@@ -70,16 +73,23 @@ $(HEADER_DEP): $(BUILDDIR)/$K/%.d : $K/%.c
         sed 's,\($*\)\.o[ :]*,\1.o $@ : ,g' < $@.$$$$ > $@; \
         rm -f $@.$$$$
 
+os/link_app.o: $K/link_app.S
+os/link_app.S: scripts/pack.py
+	@$(PY) scripts/pack.py
+os/kernel_app.ld: scripts/kernelld.py
+	@$(PY) scripts/kernelld.py
+
 build: build/kernel
 
-build/kernel: $(OBJS)
-	$(LD) $(LDFLAGS) -T os/kernel.ld -o $(BUILDDIR)/kernel $(OBJS)
+build/kernel: $(OBJS) os/kernel_app.ld
+	$(LD) $(LDFLAGS) -T os/kernel_app.ld -o $(BUILDDIR)/kernel $(OBJS)
 	$(OBJDUMP) -S $(BUILDDIR)/kernel > $(BUILDDIR)/kernel.asm
 	$(OBJDUMP) -t $(BUILDDIR)/kernel | sed '1,/SYMBOL TABLE/d; s/ .* / /; /^$$/d' > $(BUILDDIR)/kernel.sym
 	@echo 'Build kernel done'
 
 clean:
-	rm -rf $(BUILDDIR)
+	rm -rf $(BUILDDIR) os/kernel_app.ld os/link_app.S
+	make -C $(U) clean
 
 # BOARD
 BOARD		?= qemu
@@ -105,3 +115,11 @@ debug: build/kernel .gdbinit
 	$(QEMU) $(QEMUOPTS) -S $(QEMUGDB) &
 	sleep 1
 	$(GDB)
+
+CHAPTER ?= $(shell git rev-parse --abbrev-ref HEAD | grep -oP 'ch\K[0-9]')
+
+user:
+	make -C $(U) CHAPTER=$(CHAPTER) BASE=$(BASE)
+
+test: user run
+

README.md

@@ -1,5 +1,5 @@
 # uCore-Tutorial-Code
-test-20:34
+
 Course project for THU-OS.
 
 对标 [rCore-Tutorial-v3](https://github.com/rcore-os/rCore-Tutorial-v3/) 的 C 版本代码。

os/const.h

@@ -0,0 +1,12 @@
+#ifndef CONST_H
+#define CONST_H
+
+#define PAGE_SIZE (0x1000)
+
+enum {
+	STDIN = 0,
+	STDOUT = 1,
+	STDERR = 2,
+};
+
+#endif // CONST_H

os/defs.h

@@ -1,13 +1,17 @@
 #ifndef DEFS_H
 #define DEFS_H
 
+#include "const.h"
 #include "log.h"
 #include "printf.h"
 #include "riscv.h"
 #include "sbi.h"
+#include "string.h"
 #include "types.h"
 
 // number of elements in fixed-size array
 #define NELEM(x) (sizeof(x) / sizeof((x)[0]))
+#define MIN(a, b) (a < b ? a : b)
+#define MAX(a, b) (a > b ? a : b)
 
-#endif // DEF_H
+#endif // DEF_H

os/kernelld.py

@@ -0,0 +1,68 @@
+import os
+
+TARGET_DIR = "../user/target/"
+
+if __name__ == '__main__':
+    f = open("kernel_app.ld", mode="w")
+    apps = os.listdir(TARGET_DIR)
+    f.write(
+'''OUTPUT_ARCH(riscv)
+ENTRY(_entry)
+BASE_ADDRESS = 0x80200000;
+
+SECTIONS
+{
+    . = BASE_ADDRESS;
+    skernel = .;
+
+    s_text = .;
+    .text : {
+        *(.text.entry)
+        *(.text .text.*)
+        . = ALIGN(0x1000);
+        *(trampsec)
+        . = ALIGN(0x1000);
+    }
+
+    . = ALIGN(4K);
+    e_text = .;
+    s_rodata = .;
+    .rodata : {
+        *(.rodata .rodata.*)
+    }
+
+    . = ALIGN(4K);
+    e_rodata = .;
+    s_data = .;
+    .data : {
+        *(.data)
+''')
+    for (idx, _) in enumerate(apps):
+        f.write('        . = ALIGN(0x1000);\n')
+        f.write('        *(.data.app{})\n'.format(idx))
+    f.write(
+'''
+        *(.data.*)
+        *(.sdata .sdata.*)
+    }
+    
+    . = ALIGN(4K);
+    e_data = .;
+    .bss : {
+        *(.bss.stack)
+        s_bss = .;
+        *(.bss .bss.*)
+        *(.sbss .sbss.*)
+    }
+
+    . = ALIGN(4K);
+    e_bss = .;
+    ekernel = .;
+
+    /DISCARD/ : {
+        *(.eh_frame)
+    }
+}
+''')
+    f.close()
+

os/loader.c

@@ -0,0 +1,46 @@
+#include "loader.h"
+#include "defs.h"
+#include "trap.h"
+
+static int app_cur, app_num;
+static uint64 *app_info_ptr;
+extern char _app_num[], userret[], boot_stack_top[], ekernel[];
+
+void loader_init()
+{
+	if ((uint64)ekernel >= BASE_ADDRESS) {
+		panic("kernel too large...\n");
+	}
+	app_info_ptr = (uint64 *)_app_num;
+	app_cur = -1;
+	app_num = *app_info_ptr;
+}
+
+__attribute__((aligned(4096))) char user_stack[USER_STACK_SIZE];
+__attribute__((aligned(4096))) char trap_page[TRAP_PAGE_SIZE];
+
+int load_app(uint64 *info)
+{
+	uint64 start = info[0], end = info[1], length = end - start;
+	memset((void *)BASE_ADDRESS, 0, MAX_APP_SIZE);
+	memmove((void *)BASE_ADDRESS, (void *)start, length);
+	return length;
+}
+
+int run_next_app()
+{
+	struct trapframe *trapframe = (struct trapframe *)trap_page;
+	app_cur++;
+	app_info_ptr++;
+	if (app_cur >= app_num) {
+		return -1;
+	}
+	infof("load and run app %d", app_cur);
+	uint64 length = load_app(app_info_ptr);
+	debugf("bin range = [%p, %p)", *app_info_ptr, *app_info_ptr + length);
+	memset(trapframe, 0, 4096);
+	trapframe->epc = BASE_ADDRESS;
+	trapframe->sp = (uint64)user_stack + USER_STACK_SIZE;
+	usertrapret(trapframe, (uint64)boot_stack_top);
+	return 0;
+}

os/loader.h

@@ -0,0 +1,15 @@
+#ifndef BATCH_H
+#define BATCH_H
+
+#include "const.h"
+#include "types.h"
+
+void loader_init();
+int run_next_app();
+
+#define BASE_ADDRESS (0x80400000)
+#define MAX_APP_SIZE (0x20000)
+#define USER_STACK_SIZE PAGE_SIZE
+#define TRAP_PAGE_SIZE PAGE_SIZE
+
+#endif // BATCH_H

os/log.h

@@ -3,7 +3,7 @@
 
 extern void printf(char *, ...);
 extern int threadid();
-extern void shutdown();
+extern void dummy(int, ...);
 
 #if defined(LOG_LEVEL_ERROR)
 
@@ -61,7 +61,7 @@ enum LOG_COLOR {
 		       ##__VA_ARGS__);                                         \
 	} while (0)
 #else
-#define errorf(fmt, ...)
+#define errorf(fmt, ...) dummy(0, ##__VA_ARGS__)
 #endif // USE_LOG_ERROR
 
 #if defined(USE_LOG_WARN)
@@ -72,7 +72,7 @@ enum LOG_COLOR {
 		       ##__VA_ARGS__);                                         \
 	} while (0)
 #else
-#define warnf(fmt, ...)
+#define warnf(fmt, ...) dummy(0, ##__VA_ARGS__)
 #endif // USE_LOG_WARN
 
 #if defined(USE_LOG_INFO)
@@ -83,7 +83,7 @@ enum LOG_COLOR {
 		       ##__VA_ARGS__);                                         \
 	} while (0)
 #else
-#define infof(fmt, ...)
+#define infof(fmt, ...) dummy(0, ##__VA_ARGS__)
 #endif // USE_LOG_INFO
 
 #if defined(USE_LOG_DEBUG)
@@ -94,7 +94,7 @@ enum LOG_COLOR {
 		       ##__VA_ARGS__);                                         \
 	} while (0)
 #else
-#define debugf(fmt, ...)
+#define debugf(fmt, ...) dummy(0, ##__VA_ARGS__)
 #endif // USE_LOG_DEBUG
 
 #if defined(USE_LOG_TRACE)
@@ -105,16 +105,14 @@ enum LOG_COLOR {
 		       ##__VA_ARGS__);                                         \
 	} while (0)
 #else
-#define tracef(fmt, ...)
+#define tracef(fmt, ...) dummy(0, ##__VA_ARGS__)
 #endif // USE_LOG_TRACE
 
 #define panic(fmt, ...)                                                        \
 	do {                                                                   \
 		int tid = threadid();                                          \
 		printf("\x1b[%dm[%s %d] %s:%d: " fmt "\x1b[0m\n", RED,         \
 		       "PANIC", tid, __FILE__, __LINE__, ##__VA_ARGS__);       \
-		shutdown();                                                    \
-                                                                               \
 	} while (0)
 
 #endif //! LOG_H

os/main.c

@@ -1,14 +1,7 @@
 #include "console.h"
 #include "defs.h"
-
-extern char s_text[];
-extern char e_text[];
-extern char s_rodata[];
-extern char e_rodata[];
-extern char s_data[];
-extern char e_data[];
-extern char s_bss[];
-extern char e_bss[];
+#include "loader.h"
+#include "trap.h"
 
 int threadid()
 {
@@ -17,24 +10,16 @@ int threadid()
 
 void clean_bss()
 {
-	char *p;
-	for (p = s_bss; p < e_bss; ++p)
-		*p = 0;
+	extern char s_bss[];
+	extern char e_bss[];
+	memset(s_bss, 0, e_bss - s_bss);
 }
 
 void main()
 {
 	clean_bss();
-	console_init();
-	printf("\n");
 	printf("hello wrold!\n");
-	errorf("stext: %p", s_text);
-	warnf("etext: %p", e_text);
-	infof("sroda: %p", s_rodata);
-	debugf("eroda: %p", e_rodata);
-	debugf("sdata: %p", s_data);
-	infof("edata: %p", e_data);
-	warnf("sbss : %p", s_bss);
-	errorf("ebss : %p", e_bss);
-	panic("ALL DONE");
+	trap_init();
+	loader_init();
+	run_next_app();
 }

os/pack.py

@@ -0,0 +1,42 @@
+import os
+
+TARGET_DIR = "../user/target"
+
+if __name__ == '__main__':
+    f = open("link_app.S", mode="w")
+    apps = os.listdir(TARGET_DIR)
+    apps.sort()
+    f.write(
+'''    .align 4
+    .section .data
+    .global _app_num
+_app_num:
+    .quad {}
+'''.format(len(apps))
+    )
+
+    for (idx, _) in enumerate(apps):
+        f.write('    .quad app_{}_start\n'.format(idx))
+    f.write('    .quad app_{}_end\n'.format(len(apps) - 1))
+
+    f.write(
+'''
+    .global _app_names
+_app_names:
+''');
+
+    for app in apps:
+        app = app[:app.find('.')]
+        f.write("   .string \"" + app + "\"\n")
+
+    for (idx, app) in enumerate(apps):
+        f.write(
+'''
+    .section .data.app{0}
+    .global app_{0}_start
+app_{0}_start:
+    .incbin "{1}"
+'''.format(idx, TARGET_DIR + app)
+        )
+    f.write('app_{}_end:\n\n'.format(len(apps) - 1))
+    f.close()