+#include "init.h"
#include <stdint.h>
#include <stddef.h>
#include <limits.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"
+#ifdef USERPROG
+#include "exception.h"
+#include "gdt.h"
+#include "tss.h"
+#endif
#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 init_page_table (void);
-static void setup_gdt (void);
-void power_off (void);
+#ifdef FILESYS
+/* Format the filesystem? */
+static bool format_filesys;
+#endif
-struct thread *a, *b;
+#ifdef USERPROG
+/* Initial program to run. */
+static char *initial_program;
+#endif
-static void
-tfunc (void *aux UNUSED)
-{
- for (;;)
- {
- size_t count, i;
- if (random_ulong () % 5 == 0)
- {
- printk ("%s exiting\n", thread_current ()->name);
- break;
- }
- count = random_ulong () % 25 * 10000;
- printk ("%s waiting %zu: ", thread_current ()->name, count);
- for (i = 0; i < count; i++);
- printk ("%s\n", thread_current ()->name);
- }
-}
+static thread_func main_thread;
+static void ram_init (void);
+static void argv_init (void);
int
main (void)
{
- extern char _text, _end, __bss_start;
-
- /* 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);
-
- printk ("Initializing nachos-x86, %d kB RAM detected.\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 * NBPG),
- (void *) (PHYS_BASE + ram_pages * NBPG));
+ /* Greet user. */
+ printk ("Booting cnachos86 with %'d kB RAM...\n", ram_pages * 4);
- init_page_table ();
- setup_gdt ();
+ /* Parse command line. */
+ argv_init ();
+ /* Initialize memory system, segments, paging. */
+ 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 FILESYS
- filesys_init (false);
+#ifdef USERPROG
+ exception_init ();
#endif
+ /* Do everything else in a system thread. */
thread_init ();
-
- {
- struct thread *t;
- int i;
-
- for (i = 0; i < 4; i++)
- {
- char name[2];
- name[0] = 'a' + i;
- name[1] = 0;
- t = thread_create (name, tfunc, NULL);
- }
- thread_start (t);
- }
-
- printk ("Done!\n");
- return 0;
+ thread_create ("main", main_thread, NULL);
+ thread_start ();
}
-/* Populates the page directory and page table with the kernel
- virtual mapping. */
+/* Initial thread. */
static void
-init_page_table (void)
+main_thread (void *aux UNUSED)
{
- uint32_t *pd, *pt;
- uint32_t paddr;
-
- pd = palloc_get (PAL_ASSERT | PAL_ZERO);
- pt = NULL;
- for (paddr = 0; paddr < NBPG * ram_pages; paddr += NBPG)
- {
- uint32_t vaddr = paddr + PHYS_BASE;
- size_t pde_idx = PDENO(vaddr);
- size_t pte_idx = PTENO(vaddr);
-
- if (pd[pde_idx] == 0)
- {
- pt = palloc_get (PAL_ASSERT | PAL_ZERO);
- pd[pde_idx] = (uint32_t) vtop (pt) | PG_U | PG_W | PG_P;
- }
-
- pt[pte_idx] = paddr | PG_U | PG_W | PG_P;
- }
-
- /* Set the page table. */
- asm volatile ("movl %0,%%cr3" :: "r" (vtop (pd)));
-}
+#ifdef FILESYS
+ disk_init ();
+ filesys_init (format_filesys);
+ fsutil_run ();
+#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);
+#ifdef USERPROG
+ if (initial_program != NULL)
+ thread_execute (initial_program);
+ else
+ PANIC ("no initial program specified");
+#else
+ PANIC ("boot successful");
+#endif
}
-
-static uint64_t
-make_code_desc (int dpl)
+\f
+/* 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 (uint32_t base)
-{
- return make_seg_desc (base, 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
-setup_gdt (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(0xc0020000);
- 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 (vtop (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));
-}
-\f
-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]);
}