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 If false (default), use round-robin scheduler.
46 If true, use multi-level feedback queue scheduler. */
50 /* -f: Format the file system? */
51 static bool format_filesys;
54 /* -q: Power off after kernel tasks complete? */
55 bool power_off_when_done;
57 static void ram_init (void);
58 static void paging_init (void);
60 static char **read_command_line (void);
61 static char **parse_options (char **argv);
62 static void run_actions (char **argv);
63 static void usage (void);
65 static void print_stats (void);
68 int main (void) NO_RETURN;
70 /* Pintos main program. */
76 /* Clear BSS and get machine's RAM size. */
79 /* Initialize ourselves as a thread so we can use locks. */
82 /* Initialize the console so we can use printf(). */
88 printf ("Pintos booting with %'zu kB RAM...\n", ram_pages * PGSIZE / 1024);
90 /* Break command line into arguments and parse options. */
91 argv = read_command_line ();
92 argv = parse_options (argv);
94 /* Set random seed if parse_options() didn't. */
97 /* Initialize memory system. */
108 /* Initialize interrupt handlers. */
118 /* Start thread scheduler and enable interrupts. */
120 serial_init_queue ();
124 /* Initialize file system. */
126 filesys_init (format_filesys);
129 printf ("Boot complete.\n");
131 /* Run actions specified on kernel command line. */
135 if (power_off_when_done)
140 /* Clear BSS and obtain RAM size from loader. */
144 /* The "BSS" is a segment that should be initialized to zeros.
145 It isn't actually stored on disk or zeroed by the kernel
146 loader, so we have to zero it ourselves.
148 The start and end of the BSS segment is recorded by the
149 linker as _start_bss and _end_bss. See kernel.lds. */
150 extern char _start_bss, _end_bss;
151 memset (&_start_bss, 0, &_end_bss - &_start_bss);
153 /* Get RAM size from loader. See loader.S. */
154 ram_pages = *(uint32_t *) ptov (LOADER_RAM_PGS);
157 /* Populates the base page directory and page table with the
158 kernel virtual mapping, and then sets up the CPU to use the
159 new page directory. Points base_page_dir to the page
160 directory it creates.
162 At the time this function is called, the active page table
163 (set up by loader.S) only maps the first 4 MB of RAM, so we
164 should not try to use extravagant amounts of memory.
165 Fortunately, there is no need to do so. */
172 pd = base_page_dir = palloc_get_page (PAL_ASSERT | PAL_ZERO);
174 for (page = 0; page < ram_pages; page++)
176 uintptr_t paddr = page * PGSIZE;
177 void *vaddr = ptov (paddr);
178 size_t pde_idx = pd_no (vaddr);
179 size_t pte_idx = pt_no (vaddr);
181 if (pd[pde_idx] == 0)
183 pt = palloc_get_page (PAL_ASSERT | PAL_ZERO);
184 pd[pde_idx] = pde_create (pt);
187 pt[pte_idx] = pte_create_kernel (vaddr, true);
190 /* Store the physical address of the page directory into CR3
191 aka PDBR (page directory base register). This activates our
192 new page tables immediately. See [IA32-v2a] "MOV--Move
193 to/from Control Registers" and [IA32-v3a] 3.7.5 "Base Address
194 of the Page Directory". */
195 asm volatile ("movl %0, %%cr3" :: "r" (vtop (base_page_dir)));
198 /* Breaks the kernel command line into words and returns them as
199 an argv-like array. */
201 read_command_line (void)
203 static char *argv[LOADER_ARGS_LEN / 2 + 1];
208 argc = *(uint32_t *) ptov (LOADER_ARG_CNT);
209 p = ptov (LOADER_ARGS);
210 end = p + LOADER_ARGS_LEN;
211 for (i = 0; i < argc; i++)
214 PANIC ("command line arguments overflow");
217 p += strnlen (p, end - p) + 1;
221 /* Print kernel command line. */
222 printf ("Kernel command line:");
223 for (i = 0; i < argc; i++)
224 if (strchr (argv[i], ' ') == NULL)
225 printf (" %s", argv[i]);
227 printf (" '%s'", argv[i]);
233 /* Parses options in ARGV[]
234 and returns the first non-option argument. */
236 parse_options (char **argv)
238 for (; *argv != NULL && **argv == '-'; argv++)
241 char *name = strtok_r (*argv, "=", &save_ptr);
242 char *value = strtok_r (NULL, "", &save_ptr);
244 if (!strcmp (name, "-h"))
246 else if (!strcmp (name, "-q"))
247 power_off_when_done = true;
249 else if (!strcmp (name, "-f"))
250 format_filesys = true;
252 else if (!strcmp (name, "-rs"))
253 random_init (atoi (value));
254 else if (!strcmp (name, "-mlfqs"))
257 else if (!strcmp (name, "-ul"))
258 user_page_limit = atoi (value);
261 PANIC ("unknown option `%s' (use -h for help)", name);
267 /* Runs the task specified in ARGV[1]. */
269 run_task (char **argv)
271 const char *task = argv[1];
273 printf ("Executing '%s':\n", task);
275 process_wait (process_execute (task));
279 printf ("Execution of '%s' complete.\n", task);
282 /* Executes all of the actions specified in ARGV[]
283 up to the null pointer sentinel. */
285 run_actions (char **argv)
290 char *name; /* Action name. */
291 int argc; /* # of args, including action name. */
292 void (*function) (char **argv); /* Function to execute action. */
295 /* Table of supported actions. */
296 static const struct action actions[] =
298 {"run", 2, run_task},
300 {"ls", 1, fsutil_ls},
301 {"cat", 2, fsutil_cat},
302 {"rm", 2, fsutil_rm},
303 {"put", 2, fsutil_put},
304 {"get", 2, fsutil_get},
309 while (*argv != NULL)
311 const struct action *a;
314 /* Find action name. */
315 for (a = actions; ; a++)
317 PANIC ("unknown action `%s' (use -h for help)", *argv);
318 else if (!strcmp (*argv, a->name))
321 /* Check for required arguments. */
322 for (i = 1; i < a->argc; i++)
324 PANIC ("action `%s' requires %d argument(s)", *argv, a->argc - 1);
326 /* Invoke action and advance. */
333 /* Prints a kernel command line help message and powers off the
338 printf ("\nCommand line syntax: [OPTION...] [ACTION...]\n"
339 "Options must precede actions.\n"
340 "Actions are executed in the order specified.\n"
341 "\nAvailable actions:\n"
343 " run 'PROG [ARG...]' Run PROG and wait for it to complete.\n"
345 " run TEST Run TEST.\n"
348 " ls List files in the root directory.\n"
349 " cat FILE Print FILE to the console.\n"
350 " rm FILE Delete FILE.\n"
351 "Use these actions indirectly via `pintos' -g and -p options:\n"
352 " put FILE Put FILE into file system from scratch disk.\n"
353 " get FILE Get FILE from file system into scratch disk.\n"
356 " -h Print this help message and power off.\n"
357 " -q Power off VM after actions or on panic.\n"
358 " -f Format file system disk during startup.\n"
359 " -rs=SEED Set random number seed to SEED.\n"
360 " -mlfqs Use multi-level feedback queue scheduler.\n"
362 " -ul=COUNT Limit user memory to COUNT pages.\n"
369 /* Powers down the machine we're running on,
370 as long as we're running on Bochs or qemu. */
374 const char s[] = "Shutdown";
383 printf ("Powering off...\n");
386 for (p = s; *p != '\0'; p++)
391 /* Print statistics about Pintos execution. */
395 timer_print_stats ();
396 thread_print_stats ();
400 console_print_stats ();
403 exception_print_stats ();