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 /* Break command line into arguments and parse options. */
75 argv = read_command_line ();
76 argv = parse_options (argv);
78 /* Initialize ourselves as a thread so we can use locks,
79 then enable console locking. */
84 printf ("Pintos booting with %'zu kB RAM...\n", ram_pages * PGSIZE / 1024);
86 /* Initialize memory system. */
97 /* Initialize interrupt handlers. */
107 /* Start thread scheduler and enable interrupts. */
109 serial_init_queue ();
113 /* Initialize file system. */
115 filesys_init (format_filesys);
118 printf ("Boot complete.\n");
120 /* Run actions specified on kernel command line. */
124 if (power_off_when_done)
129 /* Clear BSS and obtain RAM size from loader. */
133 /* The "BSS" is a segment that should be initialized to zeros.
134 It isn't actually stored on disk or zeroed by the kernel
135 loader, so we have to zero it ourselves.
137 The start and end of the BSS segment is recorded by the
138 linker as _start_bss and _end_bss. See kernel.lds. */
139 extern char _start_bss, _end_bss;
140 memset (&_start_bss, 0, &_end_bss - &_start_bss);
142 /* Get RAM size from loader. See loader.S. */
143 ram_pages = *(uint32_t *) ptov (LOADER_RAM_PGS);
146 /* Populates the base page directory and page table with the
147 kernel virtual mapping, and then sets up the CPU to use the
148 new page directory. Points base_page_dir to the page
149 directory it creates.
151 At the time this function is called, the active page table
152 (set up by loader.S) only maps the first 4 MB of RAM, so we
153 should not try to use extravagant amounts of memory.
154 Fortunately, there is no need to do so. */
160 extern char _start, _end_kernel_text;
162 pd = base_page_dir = palloc_get_page (PAL_ASSERT | PAL_ZERO);
164 for (page = 0; page < ram_pages; page++)
166 uintptr_t paddr = page * PGSIZE;
167 char *vaddr = ptov (paddr);
168 size_t pde_idx = pd_no (vaddr);
169 size_t pte_idx = pt_no (vaddr);
170 bool in_kernel_text = &_start <= vaddr && vaddr < &_end_kernel_text;
172 if (pd[pde_idx] == 0)
174 pt = palloc_get_page (PAL_ASSERT | PAL_ZERO);
175 pd[pde_idx] = pde_create (pt);
178 pt[pte_idx] = pte_create_kernel (vaddr, !in_kernel_text);
181 /* Store the physical address of the page directory into CR3
182 aka PDBR (page directory base register). This activates our
183 new page tables immediately. See [IA32-v2a] "MOV--Move
184 to/from Control Registers" and [IA32-v3a] 3.7.5 "Base Address
185 of the Page Directory". */
186 asm volatile ("movl %0, %%cr3" : : "r" (vtop (base_page_dir)));
189 /* Breaks the kernel command line into words and returns them as
190 an argv-like array. */
192 read_command_line (void)
194 static char *argv[LOADER_ARGS_LEN / 2 + 1];
199 argc = *(uint32_t *) ptov (LOADER_ARG_CNT);
200 p = ptov (LOADER_ARGS);
201 end = p + LOADER_ARGS_LEN;
202 for (i = 0; i < argc; i++)
205 PANIC ("command line arguments overflow");
208 p += strnlen (p, end - p) + 1;
212 /* Print kernel command line. */
213 printf ("Kernel command line:");
214 for (i = 0; i < argc; i++)
215 if (strchr (argv[i], ' ') == NULL)
216 printf (" %s", argv[i]);
218 printf (" '%s'", argv[i]);
224 /* Parses options in ARGV[]
225 and returns the first non-option argument. */
227 parse_options (char **argv)
229 for (; *argv != NULL && **argv == '-'; argv++)
232 char *name = strtok_r (*argv, "=", &save_ptr);
233 char *value = strtok_r (NULL, "", &save_ptr);
235 if (!strcmp (name, "-h"))
237 else if (!strcmp (name, "-q"))
238 power_off_when_done = true;
240 else if (!strcmp (name, "-f"))
241 format_filesys = true;
243 else if (!strcmp (name, "-rs"))
244 random_init (atoi (value));
245 else if (!strcmp (name, "-mlfqs"))
248 else if (!strcmp (name, "-ul"))
249 user_page_limit = atoi (value);
252 PANIC ("unknown option `%s' (use -h for help)", name);
258 /* Runs the task specified in ARGV[1]. */
260 run_task (char **argv)
262 const char *task = argv[1];
264 printf ("Executing '%s':\n", task);
266 process_wait (process_execute (task));
270 printf ("Execution of '%s' complete.\n", task);
273 /* Executes all of the actions specified in ARGV[]
274 up to the null pointer sentinel. */
276 run_actions (char **argv)
281 char *name; /* Action name. */
282 int argc; /* # of args, including action name. */
283 void (*function) (char **argv); /* Function to execute action. */
286 /* Table of supported actions. */
287 static const struct action actions[] =
289 {"run", 2, run_task},
291 {"ls", 1, fsutil_ls},
292 {"cat", 2, fsutil_cat},
293 {"rm", 2, fsutil_rm},
294 {"put", 2, fsutil_put},
295 {"get", 2, fsutil_get},
300 while (*argv != NULL)
302 const struct action *a;
305 /* Find action name. */
306 for (a = actions; ; a++)
308 PANIC ("unknown action `%s' (use -h for help)", *argv);
309 else if (!strcmp (*argv, a->name))
312 /* Check for required arguments. */
313 for (i = 1; i < a->argc; i++)
315 PANIC ("action `%s' requires %d argument(s)", *argv, a->argc - 1);
317 /* Invoke action and advance. */
324 /* Prints a kernel command line help message and powers off the
329 printf ("\nCommand line syntax: [OPTION...] [ACTION...]\n"
330 "Options must precede actions.\n"
331 "Actions are executed in the order specified.\n"
332 "\nAvailable actions:\n"
334 " run 'PROG [ARG...]' Run PROG and wait for it to complete.\n"
336 " run TEST Run TEST.\n"
339 " ls List files in the root directory.\n"
340 " cat FILE Print FILE to the console.\n"
341 " rm FILE Delete FILE.\n"
342 "Use these actions indirectly via `pintos' -g and -p options:\n"
343 " put FILE Put FILE into file system from scratch disk.\n"
344 " get FILE Get FILE from file system into scratch disk.\n"
347 " -h Print this help message and power off.\n"
348 " -q Power off VM after actions or on panic.\n"
349 " -f Format file system disk during startup.\n"
350 " -rs=SEED Set random number seed to SEED.\n"
351 " -mlfqs Use multi-level feedback queue scheduler.\n"
353 " -ul=COUNT Limit user memory to COUNT pages.\n"
360 /* Powers down the machine we're running on,
361 as long as we're running on Bochs or QEMU. */
365 const char s[] = "Shutdown";
374 printf ("Powering off...\n");
377 for (p = s; *p != '\0'; p++)
379 asm volatile ("cli; hlt" : : : "memory");
380 printf ("still running...\n");
384 /* Print statistics about Pintos execution. */
388 timer_print_stats ();
389 thread_print_stats ();
393 console_print_stats ();
396 exception_print_stats ();