1 #include "threads/init.h"
11 #include "devices/kbd.h"
12 #include "devices/input.h"
13 #include "devices/serial.h"
14 #include "devices/timer.h"
15 #include "devices/vga.h"
16 #include "threads/interrupt.h"
17 #include "threads/io.h"
18 #include "threads/loader.h"
19 #include "threads/malloc.h"
20 #include "threads/palloc.h"
21 #include "threads/pte.h"
22 #include "threads/thread.h"
24 #include "userprog/process.h"
25 #include "userprog/exception.h"
26 #include "userprog/gdt.h"
27 #include "userprog/syscall.h"
28 #include "userprog/tss.h"
30 #include "tests/threads/tests.h"
33 #include "devices/disk.h"
34 #include "filesys/filesys.h"
35 #include "filesys/fsutil.h"
38 /* Amount of physical memory, in 4 kB pages. */
41 /* Page directory with kernel mappings only. */
42 uint32_t *base_page_dir;
45 /* -f: Format the file system? */
46 static bool format_filesys;
49 /* -q: Power off after kernel tasks complete? */
50 bool power_off_when_done;
52 static void ram_init (void);
53 static void paging_init (void);
55 static char **read_command_line (void);
56 static char **parse_options (char **argv);
57 static void run_actions (char **argv);
58 static void usage (void);
60 static void print_stats (void);
63 int main (void) NO_RETURN;
65 /* Pintos main program. */
71 /* Clear BSS and get machine's RAM size. */
74 /* Initialize ourselves as a thread so we can use locks. */
77 /* Initialize the console so we can use printf(). */
83 printf ("Pintos booting with %'zu kB RAM...\n", ram_pages * PGSIZE / 1024);
85 /* Break command line into arguments and parse options. */
86 argv = read_command_line ();
87 argv = parse_options (argv);
89 /* Set random seed if parse_options() didn't. */
92 /* Initialize memory system. */
103 /* Initialize interrupt handlers. */
113 /* Start thread scheduler and enable interrupts. */
115 serial_init_queue ();
119 /* Initialize file system. */
121 filesys_init (format_filesys);
124 printf ("Boot complete.\n");
126 /* Run actions specified on kernel command line. */
130 if (power_off_when_done)
135 /* Clear BSS and obtain RAM size from loader. */
139 /* The "BSS" is a segment that should be initialized to zeros.
140 It isn't actually stored on disk or zeroed by the kernel
141 loader, so we have to zero it ourselves.
143 The start and end of the BSS segment is recorded by the
144 linker as _start_bss and _end_bss. See kernel.lds. */
145 extern char _start_bss, _end_bss;
146 memset (&_start_bss, 0, &_end_bss - &_start_bss);
148 /* Get RAM size from loader. See loader.S. */
149 ram_pages = *(uint32_t *) ptov (LOADER_RAM_PGS);
152 /* Populates the base page directory and page table with the
153 kernel virtual mapping, and then sets up the CPU to use the
154 new page directory. Points base_page_dir to the page
155 directory it creates.
157 At the time this function is called, the active page table
158 (set up by loader.S) only maps the first 4 MB of RAM, so we
159 should not try to use extravagant amounts of memory.
160 Fortunately, there is no need to do so. */
166 extern char _start, _end_kernel_text;
168 pd = base_page_dir = palloc_get_page (PAL_ASSERT | PAL_ZERO);
170 for (page = 0; page < ram_pages; page++)
172 uintptr_t paddr = page * PGSIZE;
173 char *vaddr = ptov (paddr);
174 size_t pde_idx = pd_no (vaddr);
175 size_t pte_idx = pt_no (vaddr);
176 bool in_kernel_text = &_start <= vaddr && vaddr < &_end_kernel_text;
178 if (pd[pde_idx] == 0)
180 pt = palloc_get_page (PAL_ASSERT | PAL_ZERO);
181 pd[pde_idx] = pde_create (pt);
184 pt[pte_idx] = pte_create_kernel (vaddr, !in_kernel_text);
187 /* Store the physical address of the page directory into CR3
188 aka PDBR (page directory base register). This activates our
189 new page tables immediately. See [IA32-v2a] "MOV--Move
190 to/from Control Registers" and [IA32-v3a] 3.7.5 "Base Address
191 of the Page Directory". */
192 asm volatile ("movl %0, %%cr3" : : "r" (vtop (base_page_dir)));
195 /* Breaks the kernel command line into words and returns them as
196 an argv-like array. */
198 read_command_line (void)
200 static char *argv[LOADER_ARGS_LEN / 2 + 1];
205 argc = *(uint32_t *) ptov (LOADER_ARG_CNT);
206 p = ptov (LOADER_ARGS);
207 end = p + LOADER_ARGS_LEN;
208 for (i = 0; i < argc; i++)
211 PANIC ("command line arguments overflow");
214 p += strnlen (p, end - p) + 1;
218 /* Print kernel command line. */
219 printf ("Kernel command line:");
220 for (i = 0; i < argc; i++)
221 if (strchr (argv[i], ' ') == NULL)
222 printf (" %s", argv[i]);
224 printf (" '%s'", argv[i]);
230 /* Parses options in ARGV[]
231 and returns the first non-option argument. */
233 parse_options (char **argv)
235 for (; *argv != NULL && **argv == '-'; argv++)
238 char *name = strtok_r (*argv, "=", &save_ptr);
239 char *value = strtok_r (NULL, "", &save_ptr);
241 if (!strcmp (name, "-h"))
243 else if (!strcmp (name, "-q"))
244 power_off_when_done = true;
246 else if (!strcmp (name, "-f"))
247 format_filesys = true;
249 else if (!strcmp (name, "-rs"))
250 random_init (atoi (value));
251 else if (!strcmp (name, "-mlfqs"))
254 else if (!strcmp (name, "-ul"))
255 user_page_limit = atoi (value);
258 PANIC ("unknown option `%s' (use -h for help)", name);
264 /* Runs the task specified in ARGV[1]. */
266 run_task (char **argv)
268 const char *task = argv[1];
270 printf ("Executing '%s':\n", task);
272 process_wait (process_execute (task));
276 printf ("Execution of '%s' complete.\n", task);
279 /* Executes all of the actions specified in ARGV[]
280 up to the null pointer sentinel. */
282 run_actions (char **argv)
287 char *name; /* Action name. */
288 int argc; /* # of args, including action name. */
289 void (*function) (char **argv); /* Function to execute action. */
292 /* Table of supported actions. */
293 static const struct action actions[] =
295 {"run", 2, run_task},
297 {"ls", 1, fsutil_ls},
298 {"cat", 2, fsutil_cat},
299 {"rm", 2, fsutil_rm},
300 {"put", 2, fsutil_put},
301 {"get", 2, fsutil_get},
306 while (*argv != NULL)
308 const struct action *a;
311 /* Find action name. */
312 for (a = actions; ; a++)
314 PANIC ("unknown action `%s' (use -h for help)", *argv);
315 else if (!strcmp (*argv, a->name))
318 /* Check for required arguments. */
319 for (i = 1; i < a->argc; i++)
321 PANIC ("action `%s' requires %d argument(s)", *argv, a->argc - 1);
323 /* Invoke action and advance. */
330 /* Prints a kernel command line help message and powers off the
335 printf ("\nCommand line syntax: [OPTION...] [ACTION...]\n"
336 "Options must precede actions.\n"
337 "Actions are executed in the order specified.\n"
338 "\nAvailable actions:\n"
340 " run 'PROG [ARG...]' Run PROG and wait for it to complete.\n"
342 " run TEST Run TEST.\n"
345 " ls List files in the root directory.\n"
346 " cat FILE Print FILE to the console.\n"
347 " rm FILE Delete FILE.\n"
348 "Use these actions indirectly via `pintos' -g and -p options:\n"
349 " put FILE Put FILE into file system from scratch disk.\n"
350 " get FILE Get FILE from file system into scratch disk.\n"
353 " -h Print this help message and power off.\n"
354 " -q Power off VM after actions or on panic.\n"
355 " -f Format file system disk during startup.\n"
356 " -rs=SEED Set random number seed to SEED.\n"
357 " -mlfqs Use multi-level feedback queue scheduler.\n"
359 " -ul=COUNT Limit user memory to COUNT pages.\n"
366 /* Powers down the machine we're running on,
367 as long as we're running on Bochs or QEMU. */
371 const char s[] = "Shutdown";
380 printf ("Powering off...\n");
383 for (p = s; *p != '\0'; p++)
385 asm volatile ("cli; hlt" : : : "memory");
386 printf ("still running...\n");
390 /* Print statistics about Pintos execution. */
394 timer_print_stats ();
395 thread_print_stats ();
399 console_print_stats ();
402 exception_print_stats ();