process_kern.c 9.6 KB

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  1. /*
  2. * Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.com)
  3. * Copyright 2003 PathScale, Inc.
  4. * Licensed under the GPL
  5. */
  6. #include "linux/config.h"
  7. #include "linux/kernel.h"
  8. #include "linux/sched.h"
  9. #include "linux/interrupt.h"
  10. #include "linux/mm.h"
  11. #include "linux/slab.h"
  12. #include "linux/utsname.h"
  13. #include "linux/fs.h"
  14. #include "linux/utime.h"
  15. #include "linux/smp_lock.h"
  16. #include "linux/module.h"
  17. #include "linux/init.h"
  18. #include "linux/capability.h"
  19. #include "linux/vmalloc.h"
  20. #include "linux/spinlock.h"
  21. #include "linux/proc_fs.h"
  22. #include "linux/ptrace.h"
  23. #include "linux/random.h"
  24. #include "asm/unistd.h"
  25. #include "asm/mman.h"
  26. #include "asm/segment.h"
  27. #include "asm/stat.h"
  28. #include "asm/pgtable.h"
  29. #include "asm/processor.h"
  30. #include "asm/tlbflush.h"
  31. #include "asm/uaccess.h"
  32. #include "asm/user.h"
  33. #include "user_util.h"
  34. #include "kern_util.h"
  35. #include "kern.h"
  36. #include "signal_kern.h"
  37. #include "signal_user.h"
  38. #include "init.h"
  39. #include "irq_user.h"
  40. #include "mem_user.h"
  41. #include "time_user.h"
  42. #include "tlb.h"
  43. #include "frame_kern.h"
  44. #include "sigcontext.h"
  45. #include "os.h"
  46. #include "mode.h"
  47. #include "mode_kern.h"
  48. #include "choose-mode.h"
  49. /* This is a per-cpu array. A processor only modifies its entry and it only
  50. * cares about its entry, so it's OK if another processor is modifying its
  51. * entry.
  52. */
  53. struct cpu_task cpu_tasks[NR_CPUS] = { [0 ... NR_CPUS - 1] = { -1, NULL } };
  54. struct task_struct *get_task(int pid, int require)
  55. {
  56. struct task_struct *ret;
  57. read_lock(&tasklist_lock);
  58. ret = find_task_by_pid(pid);
  59. read_unlock(&tasklist_lock);
  60. if(require && (ret == NULL)) panic("get_task couldn't find a task\n");
  61. return(ret);
  62. }
  63. int external_pid(void *t)
  64. {
  65. struct task_struct *task = t ? t : current;
  66. return(CHOOSE_MODE_PROC(external_pid_tt, external_pid_skas, task));
  67. }
  68. int pid_to_processor_id(int pid)
  69. {
  70. int i;
  71. for(i = 0; i < ncpus; i++){
  72. if(cpu_tasks[i].pid == pid) return(i);
  73. }
  74. return(-1);
  75. }
  76. void free_stack(unsigned long stack, int order)
  77. {
  78. free_pages(stack, order);
  79. }
  80. unsigned long alloc_stack(int order, int atomic)
  81. {
  82. unsigned long page;
  83. int flags = GFP_KERNEL;
  84. if(atomic) flags |= GFP_ATOMIC;
  85. page = __get_free_pages(flags, order);
  86. if(page == 0)
  87. return(0);
  88. stack_protections(page);
  89. return(page);
  90. }
  91. int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
  92. {
  93. int pid;
  94. current->thread.request.u.thread.proc = fn;
  95. current->thread.request.u.thread.arg = arg;
  96. pid = do_fork(CLONE_VM | CLONE_UNTRACED | flags, 0, NULL, 0, NULL,
  97. NULL);
  98. if(pid < 0)
  99. panic("do_fork failed in kernel_thread, errno = %d", pid);
  100. return(pid);
  101. }
  102. void set_current(void *t)
  103. {
  104. struct task_struct *task = t;
  105. cpu_tasks[task->thread_info->cpu] = ((struct cpu_task)
  106. { external_pid(task), task });
  107. }
  108. void *_switch_to(void *prev, void *next, void *last)
  109. {
  110. return(CHOOSE_MODE(switch_to_tt(prev, next),
  111. switch_to_skas(prev, next)));
  112. }
  113. void interrupt_end(void)
  114. {
  115. if(need_resched()) schedule();
  116. if(test_tsk_thread_flag(current, TIF_SIGPENDING)) do_signal();
  117. }
  118. void release_thread(struct task_struct *task)
  119. {
  120. CHOOSE_MODE(release_thread_tt(task), release_thread_skas(task));
  121. }
  122. void exit_thread(void)
  123. {
  124. unprotect_stack((unsigned long) current_thread);
  125. }
  126. void *get_current(void)
  127. {
  128. return(current);
  129. }
  130. int copy_thread(int nr, unsigned long clone_flags, unsigned long sp,
  131. unsigned long stack_top, struct task_struct * p,
  132. struct pt_regs *regs)
  133. {
  134. p->thread = (struct thread_struct) INIT_THREAD;
  135. return(CHOOSE_MODE_PROC(copy_thread_tt, copy_thread_skas, nr,
  136. clone_flags, sp, stack_top, p, regs));
  137. }
  138. void initial_thread_cb(void (*proc)(void *), void *arg)
  139. {
  140. int save_kmalloc_ok = kmalloc_ok;
  141. kmalloc_ok = 0;
  142. CHOOSE_MODE_PROC(initial_thread_cb_tt, initial_thread_cb_skas, proc,
  143. arg);
  144. kmalloc_ok = save_kmalloc_ok;
  145. }
  146. unsigned long stack_sp(unsigned long page)
  147. {
  148. return(page + PAGE_SIZE - sizeof(void *));
  149. }
  150. int current_pid(void)
  151. {
  152. return(current->pid);
  153. }
  154. void default_idle(void)
  155. {
  156. uml_idle_timer();
  157. atomic_inc(&init_mm.mm_count);
  158. current->mm = &init_mm;
  159. current->active_mm = &init_mm;
  160. while(1){
  161. /* endless idle loop with no priority at all */
  162. /*
  163. * although we are an idle CPU, we do not want to
  164. * get into the scheduler unnecessarily.
  165. */
  166. if(need_resched())
  167. schedule();
  168. idle_sleep(10);
  169. }
  170. }
  171. void cpu_idle(void)
  172. {
  173. CHOOSE_MODE(init_idle_tt(), init_idle_skas());
  174. }
  175. int page_size(void)
  176. {
  177. return(PAGE_SIZE);
  178. }
  179. unsigned long page_mask(void)
  180. {
  181. return(PAGE_MASK);
  182. }
  183. void *um_virt_to_phys(struct task_struct *task, unsigned long addr,
  184. pte_t *pte_out)
  185. {
  186. pgd_t *pgd;
  187. pud_t *pud;
  188. pmd_t *pmd;
  189. pte_t *pte;
  190. if(task->mm == NULL)
  191. return(ERR_PTR(-EINVAL));
  192. pgd = pgd_offset(task->mm, addr);
  193. if(!pgd_present(*pgd))
  194. return(ERR_PTR(-EINVAL));
  195. pud = pud_offset(pgd, addr);
  196. if(!pud_present(*pud))
  197. return(ERR_PTR(-EINVAL));
  198. pmd = pmd_offset(pud, addr);
  199. if(!pmd_present(*pmd))
  200. return(ERR_PTR(-EINVAL));
  201. pte = pte_offset_kernel(pmd, addr);
  202. if(!pte_present(*pte))
  203. return(ERR_PTR(-EINVAL));
  204. if(pte_out != NULL)
  205. *pte_out = *pte;
  206. return((void *) (pte_val(*pte) & PAGE_MASK) + (addr & ~PAGE_MASK));
  207. }
  208. char *current_cmd(void)
  209. {
  210. #if defined(CONFIG_SMP) || defined(CONFIG_HIGHMEM)
  211. return("(Unknown)");
  212. #else
  213. void *addr = um_virt_to_phys(current, current->mm->arg_start, NULL);
  214. return IS_ERR(addr) ? "(Unknown)": __va((unsigned long) addr);
  215. #endif
  216. }
  217. void force_sigbus(void)
  218. {
  219. printk(KERN_ERR "Killing pid %d because of a lack of memory\n",
  220. current->pid);
  221. lock_kernel();
  222. sigaddset(&current->pending.signal, SIGBUS);
  223. recalc_sigpending();
  224. current->flags |= PF_SIGNALED;
  225. do_exit(SIGBUS | 0x80);
  226. }
  227. void dump_thread(struct pt_regs *regs, struct user *u)
  228. {
  229. }
  230. void enable_hlt(void)
  231. {
  232. panic("enable_hlt");
  233. }
  234. EXPORT_SYMBOL(enable_hlt);
  235. void disable_hlt(void)
  236. {
  237. panic("disable_hlt");
  238. }
  239. EXPORT_SYMBOL(disable_hlt);
  240. void *um_kmalloc(int size)
  241. {
  242. return(kmalloc(size, GFP_KERNEL));
  243. }
  244. void *um_kmalloc_atomic(int size)
  245. {
  246. return(kmalloc(size, GFP_ATOMIC));
  247. }
  248. void *um_vmalloc(int size)
  249. {
  250. return(vmalloc(size));
  251. }
  252. unsigned long get_fault_addr(void)
  253. {
  254. return((unsigned long) current->thread.fault_addr);
  255. }
  256. EXPORT_SYMBOL(get_fault_addr);
  257. void not_implemented(void)
  258. {
  259. printk(KERN_DEBUG "Something isn't implemented in here\n");
  260. }
  261. EXPORT_SYMBOL(not_implemented);
  262. int user_context(unsigned long sp)
  263. {
  264. unsigned long stack;
  265. stack = sp & (PAGE_MASK << CONFIG_KERNEL_STACK_ORDER);
  266. return(stack != (unsigned long) current_thread);
  267. }
  268. extern void remove_umid_dir(void);
  269. __uml_exitcall(remove_umid_dir);
  270. extern exitcall_t __uml_exitcall_begin, __uml_exitcall_end;
  271. void do_uml_exitcalls(void)
  272. {
  273. exitcall_t *call;
  274. call = &__uml_exitcall_end;
  275. while (--call >= &__uml_exitcall_begin)
  276. (*call)();
  277. }
  278. char *uml_strdup(char *string)
  279. {
  280. char *new;
  281. new = kmalloc(strlen(string) + 1, GFP_KERNEL);
  282. if(new == NULL) return(NULL);
  283. strcpy(new, string);
  284. return(new);
  285. }
  286. void *get_init_task(void)
  287. {
  288. return(&init_thread_union.thread_info.task);
  289. }
  290. int copy_to_user_proc(void __user *to, void *from, int size)
  291. {
  292. return(copy_to_user(to, from, size));
  293. }
  294. int copy_from_user_proc(void *to, void __user *from, int size)
  295. {
  296. return(copy_from_user(to, from, size));
  297. }
  298. int clear_user_proc(void __user *buf, int size)
  299. {
  300. return(clear_user(buf, size));
  301. }
  302. int strlen_user_proc(char __user *str)
  303. {
  304. return(strlen_user(str));
  305. }
  306. int smp_sigio_handler(void)
  307. {
  308. #ifdef CONFIG_SMP
  309. int cpu = current_thread->cpu;
  310. IPI_handler(cpu);
  311. if(cpu != 0)
  312. return(1);
  313. #endif
  314. return(0);
  315. }
  316. int um_in_interrupt(void)
  317. {
  318. return(in_interrupt());
  319. }
  320. int cpu(void)
  321. {
  322. return(current_thread->cpu);
  323. }
  324. static atomic_t using_sysemu = ATOMIC_INIT(0);
  325. int sysemu_supported;
  326. void set_using_sysemu(int value)
  327. {
  328. if (value > sysemu_supported)
  329. return;
  330. atomic_set(&using_sysemu, value);
  331. }
  332. int get_using_sysemu(void)
  333. {
  334. return atomic_read(&using_sysemu);
  335. }
  336. static int proc_read_sysemu(char *buf, char **start, off_t offset, int size,int *eof, void *data)
  337. {
  338. if (snprintf(buf, size, "%d\n", get_using_sysemu()) < size) /*No overflow*/
  339. *eof = 1;
  340. return strlen(buf);
  341. }
  342. static int proc_write_sysemu(struct file *file,const char *buf, unsigned long count,void *data)
  343. {
  344. char tmp[2];
  345. if (copy_from_user(tmp, buf, 1))
  346. return -EFAULT;
  347. if (tmp[0] >= '0' && tmp[0] <= '2')
  348. set_using_sysemu(tmp[0] - '0');
  349. return count; /*We use the first char, but pretend to write everything*/
  350. }
  351. int __init make_proc_sysemu(void)
  352. {
  353. struct proc_dir_entry *ent;
  354. if (!sysemu_supported)
  355. return 0;
  356. ent = create_proc_entry("sysemu", 0600, &proc_root);
  357. if (ent == NULL)
  358. {
  359. printk("Failed to register /proc/sysemu\n");
  360. return(0);
  361. }
  362. ent->read_proc = proc_read_sysemu;
  363. ent->write_proc = proc_write_sysemu;
  364. return 0;
  365. }
  366. late_initcall(make_proc_sysemu);
  367. int singlestepping(void * t)
  368. {
  369. struct task_struct *task = t ? t : current;
  370. if ( ! (task->ptrace & PT_DTRACE) )
  371. return(0);
  372. if (task->thread.singlestep_syscall)
  373. return(1);
  374. return 2;
  375. }
  376. /*
  377. * Only x86 and x86_64 have an arch_align_stack().
  378. * All other arches have "#define arch_align_stack(x) (x)"
  379. * in their asm/system.h
  380. * As this is included in UML from asm-um/system-generic.h,
  381. * we can use it to behave as the subarch does.
  382. */
  383. #ifndef arch_align_stack
  384. unsigned long arch_align_stack(unsigned long sp)
  385. {
  386. if (randomize_va_space)
  387. sp -= get_random_int() % 8192;
  388. return sp & ~0xf;
  389. }
  390. #endif
  391. /*
  392. * Overrides for Emacs so that we follow Linus's tabbing style.
  393. * Emacs will notice this stuff at the end of the file and automatically
  394. * adjust the settings for this buffer only. This must remain at the end
  395. * of the file.
  396. * ---------------------------------------------------------------------------
  397. * Local variables:
  398. * c-file-style: "linux"
  399. * End:
  400. */