process.c 9.4 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/kernel.h"
  7. #include "linux/sched.h"
  8. #include "linux/interrupt.h"
  9. #include "linux/string.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 "linux/personality.h"
  25. #include "asm/unistd.h"
  26. #include "asm/mman.h"
  27. #include "asm/segment.h"
  28. #include "asm/stat.h"
  29. #include "asm/pgtable.h"
  30. #include "asm/processor.h"
  31. #include "asm/tlbflush.h"
  32. #include "asm/uaccess.h"
  33. #include "asm/user.h"
  34. #include "user_util.h"
  35. #include "kern_util.h"
  36. #include "kern.h"
  37. #include "signal_kern.h"
  38. #include "init.h"
  39. #include "irq_user.h"
  40. #include "mem_user.h"
  41. #include "tlb.h"
  42. #include "frame_kern.h"
  43. #include "sigcontext.h"
  44. #include "os.h"
  45. #include "mode.h"
  46. #include "mode_kern.h"
  47. #include "choose-mode.h"
  48. #include "um_malloc.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. int external_pid(void *t)
  55. {
  56. struct task_struct *task = t ? t : current;
  57. return(CHOOSE_MODE_PROC(external_pid_tt, external_pid_skas, task));
  58. }
  59. int pid_to_processor_id(int pid)
  60. {
  61. int i;
  62. for(i = 0; i < ncpus; i++){
  63. if(cpu_tasks[i].pid == pid) return(i);
  64. }
  65. return(-1);
  66. }
  67. void free_stack(unsigned long stack, int order)
  68. {
  69. free_pages(stack, order);
  70. }
  71. unsigned long alloc_stack(int order, int atomic)
  72. {
  73. unsigned long page;
  74. gfp_t flags = GFP_KERNEL;
  75. if (atomic)
  76. flags = GFP_ATOMIC;
  77. page = __get_free_pages(flags, order);
  78. if(page == 0)
  79. return(0);
  80. stack_protections(page);
  81. return(page);
  82. }
  83. int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
  84. {
  85. int pid;
  86. current->thread.request.u.thread.proc = fn;
  87. current->thread.request.u.thread.arg = arg;
  88. pid = do_fork(CLONE_VM | CLONE_UNTRACED | flags, 0,
  89. &current->thread.regs, 0, NULL, NULL);
  90. if(pid < 0)
  91. panic("do_fork failed in kernel_thread, errno = %d", pid);
  92. return(pid);
  93. }
  94. void set_current(void *t)
  95. {
  96. struct task_struct *task = t;
  97. cpu_tasks[task_thread_info(task)->cpu] = ((struct cpu_task)
  98. { external_pid(task), task });
  99. }
  100. void *_switch_to(void *prev, void *next, void *last)
  101. {
  102. struct task_struct *from = prev;
  103. struct task_struct *to= next;
  104. to->thread.prev_sched = from;
  105. set_current(to);
  106. do {
  107. current->thread.saved_task = NULL ;
  108. CHOOSE_MODE_PROC(switch_to_tt, switch_to_skas, prev, next);
  109. if(current->thread.saved_task)
  110. show_regs(&(current->thread.regs));
  111. next= current->thread.saved_task;
  112. prev= current;
  113. } while(current->thread.saved_task);
  114. return(current->thread.prev_sched);
  115. }
  116. void interrupt_end(void)
  117. {
  118. if(need_resched()) schedule();
  119. if(test_tsk_thread_flag(current, TIF_SIGPENDING)) do_signal();
  120. }
  121. void release_thread(struct task_struct *task)
  122. {
  123. CHOOSE_MODE(release_thread_tt(task), release_thread_skas(task));
  124. }
  125. void exit_thread(void)
  126. {
  127. unprotect_stack((unsigned long) current_thread);
  128. }
  129. void *get_current(void)
  130. {
  131. return(current);
  132. }
  133. int copy_thread(int nr, unsigned long clone_flags, unsigned long sp,
  134. unsigned long stack_top, struct task_struct * p,
  135. struct pt_regs *regs)
  136. {
  137. int ret;
  138. p->thread = (struct thread_struct) INIT_THREAD;
  139. ret = CHOOSE_MODE_PROC(copy_thread_tt, copy_thread_skas, nr,
  140. clone_flags, sp, stack_top, p, regs);
  141. if (ret || !current->thread.forking)
  142. goto out;
  143. clear_flushed_tls(p);
  144. /*
  145. * Set a new TLS for the child thread?
  146. */
  147. if (clone_flags & CLONE_SETTLS)
  148. ret = arch_copy_tls(p);
  149. out:
  150. return ret;
  151. }
  152. void initial_thread_cb(void (*proc)(void *), void *arg)
  153. {
  154. int save_kmalloc_ok = kmalloc_ok;
  155. kmalloc_ok = 0;
  156. CHOOSE_MODE_PROC(initial_thread_cb_tt, initial_thread_cb_skas, proc,
  157. arg);
  158. kmalloc_ok = save_kmalloc_ok;
  159. }
  160. unsigned long stack_sp(unsigned long page)
  161. {
  162. return(page + PAGE_SIZE - sizeof(void *));
  163. }
  164. int current_pid(void)
  165. {
  166. return(current->pid);
  167. }
  168. void default_idle(void)
  169. {
  170. CHOOSE_MODE(uml_idle_timer(), (void) 0);
  171. while(1){
  172. /* endless idle loop with no priority at all */
  173. /*
  174. * although we are an idle CPU, we do not want to
  175. * get into the scheduler unnecessarily.
  176. */
  177. if(need_resched())
  178. schedule();
  179. idle_sleep(10);
  180. }
  181. }
  182. void cpu_idle(void)
  183. {
  184. CHOOSE_MODE(init_idle_tt(), init_idle_skas());
  185. }
  186. int page_size(void)
  187. {
  188. return(PAGE_SIZE);
  189. }
  190. void *um_virt_to_phys(struct task_struct *task, unsigned long addr,
  191. pte_t *pte_out)
  192. {
  193. pgd_t *pgd;
  194. pud_t *pud;
  195. pmd_t *pmd;
  196. pte_t *pte;
  197. pte_t ptent;
  198. if(task->mm == NULL)
  199. return(ERR_PTR(-EINVAL));
  200. pgd = pgd_offset(task->mm, addr);
  201. if(!pgd_present(*pgd))
  202. return(ERR_PTR(-EINVAL));
  203. pud = pud_offset(pgd, addr);
  204. if(!pud_present(*pud))
  205. return(ERR_PTR(-EINVAL));
  206. pmd = pmd_offset(pud, addr);
  207. if(!pmd_present(*pmd))
  208. return(ERR_PTR(-EINVAL));
  209. pte = pte_offset_kernel(pmd, addr);
  210. ptent = *pte;
  211. if(!pte_present(ptent))
  212. return(ERR_PTR(-EINVAL));
  213. if(pte_out != NULL)
  214. *pte_out = ptent;
  215. return((void *) (pte_val(ptent) & PAGE_MASK) + (addr & ~PAGE_MASK));
  216. }
  217. char *current_cmd(void)
  218. {
  219. #if defined(CONFIG_SMP) || defined(CONFIG_HIGHMEM)
  220. return("(Unknown)");
  221. #else
  222. void *addr = um_virt_to_phys(current, current->mm->arg_start, NULL);
  223. return IS_ERR(addr) ? "(Unknown)": __va((unsigned long) addr);
  224. #endif
  225. }
  226. void force_sigbus(void)
  227. {
  228. printk(KERN_ERR "Killing pid %d because of a lack of memory\n",
  229. current->pid);
  230. lock_kernel();
  231. sigaddset(&current->pending.signal, SIGBUS);
  232. recalc_sigpending();
  233. current->flags |= PF_SIGNALED;
  234. do_exit(SIGBUS | 0x80);
  235. }
  236. void dump_thread(struct pt_regs *regs, struct user *u)
  237. {
  238. }
  239. void enable_hlt(void)
  240. {
  241. panic("enable_hlt");
  242. }
  243. EXPORT_SYMBOL(enable_hlt);
  244. void disable_hlt(void)
  245. {
  246. panic("disable_hlt");
  247. }
  248. EXPORT_SYMBOL(disable_hlt);
  249. void *um_kmalloc(int size)
  250. {
  251. return kmalloc(size, GFP_KERNEL);
  252. }
  253. void *um_kmalloc_atomic(int size)
  254. {
  255. return kmalloc(size, GFP_ATOMIC);
  256. }
  257. void *um_vmalloc(int size)
  258. {
  259. return vmalloc(size);
  260. }
  261. void *um_vmalloc_atomic(int size)
  262. {
  263. return __vmalloc(size, GFP_ATOMIC | __GFP_HIGHMEM, PAGE_KERNEL);
  264. }
  265. int __cant_sleep(void) {
  266. return in_atomic() || irqs_disabled() || in_interrupt();
  267. /* Is in_interrupt() really needed? */
  268. }
  269. unsigned long get_fault_addr(void)
  270. {
  271. return((unsigned long) current->thread.fault_addr);
  272. }
  273. EXPORT_SYMBOL(get_fault_addr);
  274. void not_implemented(void)
  275. {
  276. printk(KERN_DEBUG "Something isn't implemented in here\n");
  277. }
  278. EXPORT_SYMBOL(not_implemented);
  279. int user_context(unsigned long sp)
  280. {
  281. unsigned long stack;
  282. stack = sp & (PAGE_MASK << CONFIG_KERNEL_STACK_ORDER);
  283. return(stack != (unsigned long) current_thread);
  284. }
  285. extern exitcall_t __uml_exitcall_begin, __uml_exitcall_end;
  286. void do_uml_exitcalls(void)
  287. {
  288. exitcall_t *call;
  289. call = &__uml_exitcall_end;
  290. while (--call >= &__uml_exitcall_begin)
  291. (*call)();
  292. }
  293. char *uml_strdup(char *string)
  294. {
  295. return kstrdup(string, GFP_KERNEL);
  296. }
  297. int copy_to_user_proc(void __user *to, void *from, int size)
  298. {
  299. return(copy_to_user(to, from, size));
  300. }
  301. int copy_from_user_proc(void *to, void __user *from, int size)
  302. {
  303. return(copy_from_user(to, from, size));
  304. }
  305. int clear_user_proc(void __user *buf, int size)
  306. {
  307. return(clear_user(buf, size));
  308. }
  309. int strlen_user_proc(char __user *str)
  310. {
  311. return(strlen_user(str));
  312. }
  313. int smp_sigio_handler(void)
  314. {
  315. #ifdef CONFIG_SMP
  316. int cpu = current_thread->cpu;
  317. IPI_handler(cpu);
  318. if(cpu != 0)
  319. return(1);
  320. #endif
  321. return(0);
  322. }
  323. int cpu(void)
  324. {
  325. return(current_thread->cpu);
  326. }
  327. static atomic_t using_sysemu = ATOMIC_INIT(0);
  328. int sysemu_supported;
  329. void set_using_sysemu(int value)
  330. {
  331. if (value > sysemu_supported)
  332. return;
  333. atomic_set(&using_sysemu, value);
  334. }
  335. int get_using_sysemu(void)
  336. {
  337. return atomic_read(&using_sysemu);
  338. }
  339. static int proc_read_sysemu(char *buf, char **start, off_t offset, int size,int *eof, void *data)
  340. {
  341. if (snprintf(buf, size, "%d\n", get_using_sysemu()) < size) /*No overflow*/
  342. *eof = 1;
  343. return strlen(buf);
  344. }
  345. static int proc_write_sysemu(struct file *file,const char __user *buf, unsigned long count,void *data)
  346. {
  347. char tmp[2];
  348. if (copy_from_user(tmp, buf, 1))
  349. return -EFAULT;
  350. if (tmp[0] >= '0' && tmp[0] <= '2')
  351. set_using_sysemu(tmp[0] - '0');
  352. return count; /*We use the first char, but pretend to write everything*/
  353. }
  354. int __init make_proc_sysemu(void)
  355. {
  356. struct proc_dir_entry *ent;
  357. if (!sysemu_supported)
  358. return 0;
  359. ent = create_proc_entry("sysemu", 0600, &proc_root);
  360. if (ent == NULL)
  361. {
  362. printk(KERN_WARNING "Failed to register /proc/sysemu\n");
  363. return(0);
  364. }
  365. ent->read_proc = proc_read_sysemu;
  366. ent->write_proc = proc_write_sysemu;
  367. return 0;
  368. }
  369. late_initcall(make_proc_sysemu);
  370. int singlestepping(void * t)
  371. {
  372. struct task_struct *task = t ? t : current;
  373. if ( ! (task->ptrace & PT_DTRACE) )
  374. return(0);
  375. if (task->thread.singlestep_syscall)
  376. return(1);
  377. return 2;
  378. }
  379. /*
  380. * Only x86 and x86_64 have an arch_align_stack().
  381. * All other arches have "#define arch_align_stack(x) (x)"
  382. * in their asm/system.h
  383. * As this is included in UML from asm-um/system-generic.h,
  384. * we can use it to behave as the subarch does.
  385. */
  386. #ifndef arch_align_stack
  387. unsigned long arch_align_stack(unsigned long sp)
  388. {
  389. if (!(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space)
  390. sp -= get_random_int() % 8192;
  391. return sp & ~0xf;
  392. }
  393. #endif