X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=src%2Fthreads%2Finit.c;h=a3ab43d577c5d6a98bd629883c7f1e84c840034e;hb=a051c001c942a1f9cce57b1beec79794f9c7089f;hp=8702da418738fe8df411906289bd0a6e9ca45b12;hpb=2cd697ca45bad0ab83fe78fd21d8bcc7697ae195;p=pintos-anon diff --git a/src/threads/init.c b/src/threads/init.c index 8702da4..a3ab43d 100644 --- a/src/threads/init.c +++ b/src/threads/init.c @@ -3,10 +3,12 @@ #include #include #include "debug.h" +#include "gdt.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" @@ -15,169 +17,162 @@ #include "serial.h" #include "thread.h" #include "timer.h" +#include "tss.h" #include "vga.h" #ifdef FILESYS #include "filesys.h" #include "disk.h" +#include "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 + +#ifdef USERPROG +/* Initial program to run. */ +static char *initial_program; +#endif + +static void ram_init (void); +static void argv_init (void); static void main_thread (void *aux UNUSED) { - struct disk *hda; +#ifdef FILESYS disk_init (); - hda = disk_get (0); - if (hda != NULL) - { - char buf[DISK_SECTOR_SIZE]; - disk_read (hda, 0, buf); - hex_dump (buf, sizeof buf); - } + filesys_init (format_filesys); + fsutil_run (); +#endif + +#ifdef USERPROG + if (initial_program != NULL) + thread_execute (initial_program); else - printk ("no hda\n"); - thread_execute ("a.out"); + PANIC ("no initial program specified"); +#endif } int main (void) { - extern char _text, _end, __bss_start; - struct thread *t; - - /* Clear out the BSS segment. */ - memset (&__bss_start, 0, &_end - &__bss_start); - - /* Initialize components needed by printk() very early. */ + /* Initialize prerequisites for calling printk(). */ + ram_init (); vga_init (); serial_init (); - printk ("Booting cnachos86...\n"); - - /* 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 - 6); - printk ("ram: detected %'d kB.\n", ram_pages * 4); - - /* 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)); + + /* Greet user. */ + printk ("Booting cnachos86 with %'d kB RAM...\n", ram_pages * 4); + + /* Parse command line. */ + argv_init (); + + /* Initialize memory system. */ + palloc_init (); paging_init (); + tss_init (); gdt_init (); - malloc_init (); - random_init (); + random_init (0); + + /* Initialize interrupt handlers. */ intr_init (); timer_init (); kbd_init (); -#ifdef FILESYS - filesys_init (false); -#endif - + /* Do everything else in a system thread. */ thread_init (); - - t = thread_create ("main", main_thread, NULL); - thread_start (t); - - printk ("Done!\n"); - return 0; + thread_create ("main", main_thread, NULL); + thread_start (); } -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); -} -static uint64_t -make_code_desc (int dpl) +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); -} - -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. */ -static void -gdt_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)); + /* Get RAM size from loader. */ + ram_pages = *(uint32_t *) ptov (LOADER_RAM_PAGES); } -void -power_off (void) +static void +argv_init (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]); }