X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=src%2Fthreads%2Finit.c;h=57d5301c3ae3a0477e3aeb846c0ec97b01d940b3;hb=f6580e9ad405b519dbe85027691bf3c66074b0a4;hp=234c41eb249c64def96f49d22d6775c3d3ee52ba;hpb=57da1efd4f622d93e33dfbd26ca2cd141744aaa2;p=pintos-anon diff --git a/src/threads/init.c b/src/threads/init.c index 234c41e..57d5301 100644 --- a/src/threads/init.c +++ b/src/threads/init.c @@ -2,171 +2,195 @@ #include #include #include -#include "debug.h" #include "interrupt.h" #include "io.h" -#include "kbd.h" -#include "lib.h" +#include "loader.h" #include "malloc.h" #include "mmu.h" #include "paging.h" #include "palloc.h" -#include "random.h" -#include "serial.h" #include "thread.h" -#include "timer.h" -#include "vga.h" +#include "devices/kbd.h" +#include "devices/serial.h" +#include "devices/timer.h" +#include "devices/vga.h" +#include "lib/debug.h" +#include "lib/lib.h" +#include "lib/random.h" +#ifdef USERPROG +#include "userprog/exception.h" +#include "userprog/gdt.h" +#include "userprog/syscall.h" +#include "userprog/tss.h" +#endif #ifdef FILESYS -#include "filesys.h" +#include "devices/disk.h" +#include "filesys/filesys.h" +#include "filesys/fsutil.h" #endif -/* Size of kernel static code and data, in 4 kB pages. */ -size_t kernel_pages; - /* Amount of physical memory, in 4 kB pages. */ size_t ram_pages; -static void gdt_init (void); -void power_off (void); +#ifdef FILESYS +/* Format the filesystem? */ +static bool format_filesys; +#endif -static void -main_thread (void *aux UNUSED) -{ - printk ("execute=%d\n", (int) thread_execute ("a.out")); -} +#ifdef USERPROG +/* Initial program to run. */ +static char *initial_program; +#endif + +static void ram_init (void); +static void argv_init (void); + +int main (void) NO_RETURN; int main (void) { - extern char _text, _end, __bss_start; - struct thread *t; - - /* Clear out the BSS segment. */ - memset (&__bss_start, 0, &_end - &__bss_start); - + /* Needed by printk(), so initialize them very early. */ + ram_init (); vga_init (); serial_init (); - /* Calculate how much RAM the kernel uses, and find out from - the bootloader how much RAM this machine has. */ - kernel_pages = (&_end - &_text + 4095) / 4096; - ram_pages = *(uint32_t *) (0x7e00 - 8); + /* Greet user. */ + printk ("Booting cnachos86 with %'d kB RAM...\n", ram_pages * 4); - printk ("Initializing nachos-x86, %d kB RAM detected.\n", - ram_pages * 4); + /* Parse command line. */ + argv_init (); - /* Memory from the end of the kernel through the end of memory - is free. Give it to the page allocator. */ - palloc_init ((void *) (KERN_BASE + kernel_pages * PGSIZE), - (void *) (PHYS_BASE + ram_pages * PGSIZE)); + /* Initialize memory system, segments, paging. */ + thread_init (); + palloc_init (); paging_init (); +#ifdef USERPROG + tss_init (); gdt_init (); - +#endif malloc_init (); - random_init (); + /* Set random seed if not already done. */ + random_init (0); + + /* Initialize interrupt handlers. */ intr_init (); timer_init (); kbd_init (); +#ifdef USERPROG + exception_init (); + syscall_init (); +#endif + + /* Start thread scheduler and enable interrupts. */ + thread_start (); #ifdef FILESYS - filesys_init (false); - filesys_self_test (); + /* Initialize filesystem. */ + disk_init (); + filesys_init (format_filesys); + fsutil_run (); #endif - thread_init (); + printk ("Boot complete.\n"); - t = thread_create ("main", main_thread, NULL); - thread_start (t); - - printk ("Done!\n"); - return 0; -} +#ifdef USERPROG + /* Run a user program. */ + if (initial_program != NULL) + { + printk ("\nExecuting '%s':\n", initial_program); + thread_execute (initial_program); + } +#endif -static uint64_t -make_seg_desc (uint32_t base, - uint32_t limit, - enum seg_system system, - enum seg_type type, - int dpl, - enum seg_granularity granularity) -{ - uint32_t e0 = ((limit & 0xffff) /* Limit 15:0. */ - | (base << 16)); /* Base 15:0. */ - uint32_t e1 = (((base >> 16) & 0xff) /* Base 23:16. */ - | (system << 12) /* 0=system, 1=code/data. */ - | (type << 8) /* Segment type. */ - | (dpl << 13) /* Descriptor privilege. */ - | (1 << 15) /* Present. */ - | (limit & 0xf0000) /* Limit 16:19. */ - | (1 << 22) /* 32-bit segment. */ - | (granularity << 23) /* Byte/page granularity. */ - | (base & 0xff000000)); /* Base 31:24. */ - return e0 | ((uint64_t) e1 << 32); + /* Terminate this thread. */ + thread_exit (); } - -static uint64_t -make_code_desc (int dpl) + +/* Clear BSS and obtain RAM size from loader. */ +static void +ram_init (void) { - return make_seg_desc (0, 0xfffff, SYS_CODE_DATA, TYPE_CODE | TYPE_READABLE, - dpl, GRAN_PAGE); -} + /* The "BSS" is a segment that should be initialized to zeros. + It isn't actually stored on disk or zeroed by the kernel + loader, so we have to zero it ourselves. -static uint64_t -make_data_desc (int dpl) -{ - return make_seg_desc (0, 0xfffff, SYS_CODE_DATA, TYPE_WRITABLE, - dpl, GRAN_PAGE); -} + The start and end of the BSS segment is recorded by the + linker as _start_bss and _end_bss. See kernel.lds. */ + extern char _start_bss, _end_bss; + memset (&_start_bss, 0, &_end_bss - &_start_bss); -static uint64_t -make_tss_desc (void *vaddr) -{ - return make_seg_desc ((uint32_t) vaddr, - 0x67, SYS_SYSTEM, TYPE_TSS_32_A, 0, GRAN_BYTE); + /* Get RAM size from loader. See loader.S. */ + ram_pages = *(uint32_t *) ptov (LOADER_RAM_PAGES); } -uint64_t gdt[SEL_CNT]; - -struct tss *tss; - -/* Sets up a proper GDT. The bootstrap loader's GDT didn't - include user-mode selectors or a TSS. */ +/* Parses the command line. */ static void -gdt_init (void) +argv_init (void) { - uint64_t gdtr_operand; - - /* Our TSS is never used in a call gate or task gate, so only a - few fields of it are ever referenced, and those are the only - ones we initialize. */ - tss = palloc_get (PAL_ASSERT | PAL_ZERO); - tss->esp0 = (uint32_t) ptov(0x20000); - tss->ss0 = SEL_KDSEG; - tss->bitmap = 0xdfff; - - /* Initialize GDT. */ - gdt[SEL_NULL / sizeof *gdt] = 0; - gdt[SEL_KCSEG / sizeof *gdt] = make_code_desc (0); - gdt[SEL_KDSEG / sizeof *gdt] = make_data_desc (0); - gdt[SEL_UCSEG / sizeof *gdt] = make_code_desc (3); - gdt[SEL_UDSEG / sizeof *gdt] = make_data_desc (3); - gdt[SEL_TSS / sizeof *gdt] = make_tss_desc (tss); - - /* Load GDTR, TR. */ - gdtr_operand = make_dtr_operand (sizeof gdt - 1, gdt); - asm volatile ("lgdt %0" :: "m" (gdtr_operand)); - asm volatile ("ltr %w0" :: "r" (SEL_TSS)); -} - -void -power_off (void) -{ - const char s[] = "Shutdown"; - const char *p; - - printk ("Powering off...\n"); - for (p = s; *p != '\0'; p++) - outb (0x8900, *p); - for (;;); + char *cmd_line, *pos; + char *argv[LOADER_CMD_LINE_LEN / 2 + 1]; + int argc = 0; + int i; + + /* The command line is made up of null terminated strings + followed by an empty string. Break it up into words. */ + cmd_line = pos = ptov (LOADER_CMD_LINE); + while (pos < cmd_line + LOADER_CMD_LINE_LEN) + { + ASSERT (argc < LOADER_CMD_LINE_LEN / 2); + if (*pos == '\0') + break; + argv[argc++] = pos; + pos = strchr (pos, '\0') + 1; + } + argv[argc] = ""; + + /* Parse the words. */ + for (i = 0; i < argc; i++) + if (!strcmp (argv[i], "-rs")) + random_init (atoi (argv[++i])); + else if (!strcmp (argv[i], "-d")) + debug_enable (argv[++i]); +#ifdef USERPROG + else if (!strcmp (argv[i], "-ex")) + initial_program = argv[++i]; +#endif +#ifdef FILESYS + else if (!strcmp (argv[i], "-f")) + format_filesys = true; + else if (!strcmp (argv[i], "-cp")) + fsutil_copy_arg = argv[++i]; + else if (!strcmp (argv[i], "-p")) + fsutil_print_file = argv[++i]; + else if (!strcmp (argv[i], "-r")) + fsutil_remove_file = argv[++i]; + else if (!strcmp (argv[i], "-ls")) + fsutil_list_files = true; + else if (!strcmp (argv[i], "-D")) + fsutil_dump_filesys = true; +#endif + else if (!strcmp (argv[i], "-u")) + { + printk ( + "Kernel options:\n" + " -rs SEED Seed random seed to SEED.\n" + " -d CLASS[,...] Enable the given classes of debug messages.\n" +#ifdef USERPROG + " -ex 'PROG [ARG...]' Run PROG, passing the optional arguments.\n" +#endif +#ifdef FILESYS + " -f Format the filesystem disk (hdb or hd0:1).\n" + " -cp FILENAME:SIZE Copy SIZE bytes from the scratch disk (hdc\n" + " or hd1:0) into the filesystem as FILENAME\n" + " -p FILENAME Print the contents of FILENAME\n" + " -r FILENAME Delete FILENAME\n" + " -ls List the files in the filesystem\n" + " -D Dump complete filesystem contents\n" +#endif + ); + } + else + PANIC ("unknown option `%s'", argv[i]); }