Commit | Line | Data |
---|---|---|
995473ae | 1 | /* |
ba180fd4 | 2 | * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com) |
1da177e4 LT |
3 | * Copyright 2003 PathScale, Inc. |
4 | * Licensed under the GPL | |
5 | */ | |
6 | ||
ba180fd4 JD |
7 | #include "linux/stddef.h" |
8 | #include "linux/err.h" | |
9 | #include "linux/hardirq.h" | |
1da177e4 | 10 | #include "linux/mm.h" |
ba180fd4 | 11 | #include "linux/personality.h" |
1da177e4 LT |
12 | #include "linux/proc_fs.h" |
13 | #include "linux/ptrace.h" | |
14 | #include "linux/random.h" | |
ba180fd4 | 15 | #include "linux/sched.h" |
d2753a6d | 16 | #include "linux/tick.h" |
ba180fd4 | 17 | #include "linux/threads.h" |
1da177e4 | 18 | #include "asm/pgtable.h" |
1da177e4 | 19 | #include "asm/uaccess.h" |
4ff83ce1 | 20 | #include "as-layout.h" |
ba180fd4 | 21 | #include "kern_util.h" |
1da177e4 | 22 | #include "os.h" |
77bf4400 | 23 | #include "skas.h" |
ba180fd4 | 24 | #include "tlb.h" |
1da177e4 | 25 | |
ba180fd4 JD |
26 | /* |
27 | * This is a per-cpu array. A processor only modifies its entry and it only | |
1da177e4 LT |
28 | * cares about its entry, so it's OK if another processor is modifying its |
29 | * entry. | |
30 | */ | |
31 | struct cpu_task cpu_tasks[NR_CPUS] = { [0 ... NR_CPUS - 1] = { -1, NULL } }; | |
32 | ||
6e21aec3 | 33 | static inline int external_pid(struct task_struct *task) |
1da177e4 | 34 | { |
77bf4400 | 35 | /* FIXME: Need to look up userspace_pid by cpu */ |
ba180fd4 | 36 | return userspace_pid[0]; |
1da177e4 LT |
37 | } |
38 | ||
39 | int pid_to_processor_id(int pid) | |
40 | { | |
41 | int i; | |
42 | ||
ba180fd4 JD |
43 | for(i = 0; i < ncpus; i++) { |
44 | if (cpu_tasks[i].pid == pid) | |
6e21aec3 | 45 | return i; |
1da177e4 | 46 | } |
6e21aec3 | 47 | return -1; |
1da177e4 LT |
48 | } |
49 | ||
50 | void free_stack(unsigned long stack, int order) | |
51 | { | |
52 | free_pages(stack, order); | |
53 | } | |
54 | ||
55 | unsigned long alloc_stack(int order, int atomic) | |
56 | { | |
57 | unsigned long page; | |
53f9fc93 | 58 | gfp_t flags = GFP_KERNEL; |
1da177e4 | 59 | |
46db4a42 PBG |
60 | if (atomic) |
61 | flags = GFP_ATOMIC; | |
1da177e4 | 62 | page = __get_free_pages(flags, order); |
5c8aacea | 63 | if (page == 0) |
6e21aec3 | 64 | return 0; |
5c8aacea | 65 | |
6e21aec3 | 66 | return page; |
1da177e4 LT |
67 | } |
68 | ||
69 | int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags) | |
70 | { | |
71 | int pid; | |
72 | ||
73 | current->thread.request.u.thread.proc = fn; | |
74 | current->thread.request.u.thread.arg = arg; | |
e0877f07 JD |
75 | pid = do_fork(CLONE_VM | CLONE_UNTRACED | flags, 0, |
76 | ¤t->thread.regs, 0, NULL, NULL); | |
6e21aec3 | 77 | return pid; |
1da177e4 LT |
78 | } |
79 | ||
6e21aec3 | 80 | static inline void set_current(struct task_struct *task) |
1da177e4 | 81 | { |
ca9bc0bb | 82 | cpu_tasks[task_thread_info(task)->cpu] = ((struct cpu_task) |
1da177e4 LT |
83 | { external_pid(task), task }); |
84 | } | |
85 | ||
77bf4400 JD |
86 | extern void arch_switch_to(struct task_struct *from, struct task_struct *to); |
87 | ||
1da177e4 LT |
88 | void *_switch_to(void *prev, void *next, void *last) |
89 | { | |
995473ae JD |
90 | struct task_struct *from = prev; |
91 | struct task_struct *to= next; | |
f6e34c6a | 92 | |
995473ae JD |
93 | to->thread.prev_sched = from; |
94 | set_current(to); | |
f6e34c6a | 95 | |
3eddddcf | 96 | do { |
6aa802ce | 97 | current->thread.saved_task = NULL; |
77bf4400 | 98 | |
77bf4400 JD |
99 | switch_threads(&from->thread.switch_buf, |
100 | &to->thread.switch_buf); | |
101 | ||
102 | arch_switch_to(current->thread.prev_sched, current); | |
103 | ||
ba180fd4 | 104 | if (current->thread.saved_task) |
3eddddcf JD |
105 | show_regs(&(current->thread.regs)); |
106 | next= current->thread.saved_task; | |
107 | prev= current; | |
108 | } while(current->thread.saved_task); | |
f6e34c6a | 109 | |
6e21aec3 | 110 | return current->thread.prev_sched; |
f6e34c6a | 111 | |
1da177e4 LT |
112 | } |
113 | ||
114 | void interrupt_end(void) | |
115 | { | |
ba180fd4 | 116 | if (need_resched()) |
6e21aec3 | 117 | schedule(); |
ba180fd4 | 118 | if (test_tsk_thread_flag(current, TIF_SIGPENDING)) |
6e21aec3 | 119 | do_signal(); |
1da177e4 LT |
120 | } |
121 | ||
1da177e4 LT |
122 | void exit_thread(void) |
123 | { | |
1da177e4 | 124 | } |
995473ae | 125 | |
1da177e4 LT |
126 | void *get_current(void) |
127 | { | |
6e21aec3 | 128 | return current; |
1da177e4 LT |
129 | } |
130 | ||
77bf4400 JD |
131 | extern void schedule_tail(struct task_struct *prev); |
132 | ||
ba180fd4 JD |
133 | /* |
134 | * This is called magically, by its address being stuffed in a jmp_buf | |
77bf4400 JD |
135 | * and being longjmp-d to. |
136 | */ | |
137 | void new_thread_handler(void) | |
138 | { | |
139 | int (*fn)(void *), n; | |
140 | void *arg; | |
141 | ||
ba180fd4 | 142 | if (current->thread.prev_sched != NULL) |
77bf4400 JD |
143 | schedule_tail(current->thread.prev_sched); |
144 | current->thread.prev_sched = NULL; | |
145 | ||
146 | fn = current->thread.request.u.thread.proc; | |
147 | arg = current->thread.request.u.thread.arg; | |
148 | ||
ba180fd4 JD |
149 | /* |
150 | * The return value is 1 if the kernel thread execs a process, | |
77bf4400 JD |
151 | * 0 if it just exits |
152 | */ | |
153 | n = run_kernel_thread(fn, arg, ¤t->thread.exec_buf); | |
ba180fd4 | 154 | if (n == 1) { |
77bf4400 JD |
155 | /* Handle any immediate reschedules or signals */ |
156 | interrupt_end(); | |
157 | userspace(¤t->thread.regs.regs); | |
158 | } | |
159 | else do_exit(0); | |
160 | } | |
161 | ||
162 | /* Called magically, see new_thread_handler above */ | |
163 | void fork_handler(void) | |
164 | { | |
165 | force_flush_all(); | |
ba180fd4 | 166 | if (current->thread.prev_sched == NULL) |
77bf4400 JD |
167 | panic("blech"); |
168 | ||
169 | schedule_tail(current->thread.prev_sched); | |
170 | ||
ba180fd4 JD |
171 | /* |
172 | * XXX: if interrupt_end() calls schedule, this call to | |
77bf4400 | 173 | * arch_switch_to isn't needed. We could want to apply this to |
ba180fd4 JD |
174 | * improve performance. -bb |
175 | */ | |
77bf4400 JD |
176 | arch_switch_to(current->thread.prev_sched, current); |
177 | ||
178 | current->thread.prev_sched = NULL; | |
179 | ||
180 | /* Handle any immediate reschedules or signals */ | |
181 | interrupt_end(); | |
182 | ||
183 | userspace(¤t->thread.regs.regs); | |
184 | } | |
185 | ||
1da177e4 | 186 | int copy_thread(int nr, unsigned long clone_flags, unsigned long sp, |
995473ae | 187 | unsigned long stack_top, struct task_struct * p, |
1da177e4 LT |
188 | struct pt_regs *regs) |
189 | { | |
77bf4400 JD |
190 | void (*handler)(void); |
191 | int ret = 0; | |
aa6758d4 | 192 | |
1da177e4 | 193 | p->thread = (struct thread_struct) INIT_THREAD; |
aa6758d4 | 194 | |
ba180fd4 | 195 | if (current->thread.forking) { |
77bf4400 JD |
196 | memcpy(&p->thread.regs.regs, ®s->regs, |
197 | sizeof(p->thread.regs.regs)); | |
18baddda | 198 | REGS_SET_SYSCALL_RETURN(p->thread.regs.regs.gp, 0); |
ba180fd4 | 199 | if (sp != 0) |
18baddda | 200 | REGS_SP(p->thread.regs.regs.gp) = sp; |
aa6758d4 | 201 | |
77bf4400 | 202 | handler = fork_handler; |
aa6758d4 | 203 | |
77bf4400 JD |
204 | arch_copy_thread(¤t->thread.arch, &p->thread.arch); |
205 | } | |
206 | else { | |
207 | init_thread_registers(&p->thread.regs.regs); | |
208 | p->thread.request.u.thread = current->thread.request.u.thread; | |
209 | handler = new_thread_handler; | |
210 | } | |
211 | ||
212 | new_thread(task_stack_page(p), &p->thread.switch_buf, handler); | |
213 | ||
214 | if (current->thread.forking) { | |
215 | clear_flushed_tls(p); | |
216 | ||
217 | /* | |
218 | * Set a new TLS for the child thread? | |
219 | */ | |
220 | if (clone_flags & CLONE_SETTLS) | |
221 | ret = arch_copy_tls(p); | |
222 | } | |
aa6758d4 | 223 | |
aa6758d4 | 224 | return ret; |
1da177e4 LT |
225 | } |
226 | ||
227 | void initial_thread_cb(void (*proc)(void *), void *arg) | |
228 | { | |
229 | int save_kmalloc_ok = kmalloc_ok; | |
230 | ||
231 | kmalloc_ok = 0; | |
6aa802ce | 232 | initial_thread_cb_skas(proc, arg); |
1da177e4 LT |
233 | kmalloc_ok = save_kmalloc_ok; |
234 | } | |
995473ae | 235 | |
1da177e4 LT |
236 | void default_idle(void) |
237 | { | |
ba180fd4 | 238 | while(1) { |
1da177e4 | 239 | /* endless idle loop with no priority at all */ |
1da177e4 LT |
240 | |
241 | /* | |
242 | * although we are an idle CPU, we do not want to | |
243 | * get into the scheduler unnecessarily. | |
244 | */ | |
ba180fd4 | 245 | if (need_resched()) |
1da177e4 | 246 | schedule(); |
995473ae | 247 | |
d2753a6d | 248 | tick_nohz_stop_sched_tick(); |
181bde80 | 249 | switch_timers(1); |
1da177e4 | 250 | idle_sleep(10); |
181bde80 | 251 | switch_timers(0); |
d2753a6d | 252 | tick_nohz_restart_sched_tick(); |
1da177e4 LT |
253 | } |
254 | } | |
255 | ||
256 | void cpu_idle(void) | |
257 | { | |
77bf4400 JD |
258 | cpu_tasks[current_thread->cpu].pid = os_getpid(); |
259 | default_idle(); | |
1da177e4 LT |
260 | } |
261 | ||
995473ae | 262 | void *um_virt_to_phys(struct task_struct *task, unsigned long addr, |
1da177e4 LT |
263 | pte_t *pte_out) |
264 | { | |
265 | pgd_t *pgd; | |
266 | pud_t *pud; | |
267 | pmd_t *pmd; | |
268 | pte_t *pte; | |
8f5cd76c | 269 | pte_t ptent; |
1da177e4 | 270 | |
ba180fd4 | 271 | if (task->mm == NULL) |
6e21aec3 | 272 | return ERR_PTR(-EINVAL); |
1da177e4 | 273 | pgd = pgd_offset(task->mm, addr); |
ba180fd4 | 274 | if (!pgd_present(*pgd)) |
6e21aec3 | 275 | return ERR_PTR(-EINVAL); |
1da177e4 LT |
276 | |
277 | pud = pud_offset(pgd, addr); | |
ba180fd4 | 278 | if (!pud_present(*pud)) |
6e21aec3 | 279 | return ERR_PTR(-EINVAL); |
1da177e4 LT |
280 | |
281 | pmd = pmd_offset(pud, addr); | |
ba180fd4 | 282 | if (!pmd_present(*pmd)) |
6e21aec3 | 283 | return ERR_PTR(-EINVAL); |
1da177e4 LT |
284 | |
285 | pte = pte_offset_kernel(pmd, addr); | |
8f5cd76c | 286 | ptent = *pte; |
ba180fd4 | 287 | if (!pte_present(ptent)) |
6e21aec3 | 288 | return ERR_PTR(-EINVAL); |
1da177e4 | 289 | |
ba180fd4 | 290 | if (pte_out != NULL) |
8f5cd76c | 291 | *pte_out = ptent; |
6e21aec3 | 292 | return (void *) (pte_val(ptent) & PAGE_MASK) + (addr & ~PAGE_MASK); |
1da177e4 LT |
293 | } |
294 | ||
295 | char *current_cmd(void) | |
296 | { | |
297 | #if defined(CONFIG_SMP) || defined(CONFIG_HIGHMEM) | |
6e21aec3 | 298 | return "(Unknown)"; |
1da177e4 LT |
299 | #else |
300 | void *addr = um_virt_to_phys(current, current->mm->arg_start, NULL); | |
301 | return IS_ERR(addr) ? "(Unknown)": __va((unsigned long) addr); | |
302 | #endif | |
303 | } | |
304 | ||
1da177e4 LT |
305 | void dump_thread(struct pt_regs *regs, struct user *u) |
306 | { | |
307 | } | |
308 | ||
b6316293 PBG |
309 | int __cant_sleep(void) { |
310 | return in_atomic() || irqs_disabled() || in_interrupt(); | |
311 | /* Is in_interrupt() really needed? */ | |
1da177e4 LT |
312 | } |
313 | ||
1da177e4 LT |
314 | int user_context(unsigned long sp) |
315 | { | |
316 | unsigned long stack; | |
317 | ||
318 | stack = sp & (PAGE_MASK << CONFIG_KERNEL_STACK_ORDER); | |
6e21aec3 | 319 | return stack != (unsigned long) current_thread; |
1da177e4 LT |
320 | } |
321 | ||
1da177e4 LT |
322 | extern exitcall_t __uml_exitcall_begin, __uml_exitcall_end; |
323 | ||
324 | void do_uml_exitcalls(void) | |
325 | { | |
326 | exitcall_t *call; | |
327 | ||
328 | call = &__uml_exitcall_end; | |
329 | while (--call >= &__uml_exitcall_begin) | |
330 | (*call)(); | |
331 | } | |
332 | ||
333 | char *uml_strdup(char *string) | |
334 | { | |
dfe52244 | 335 | return kstrdup(string, GFP_KERNEL); |
1da177e4 LT |
336 | } |
337 | ||
1da177e4 LT |
338 | int copy_to_user_proc(void __user *to, void *from, int size) |
339 | { | |
6e21aec3 | 340 | return copy_to_user(to, from, size); |
1da177e4 LT |
341 | } |
342 | ||
343 | int copy_from_user_proc(void *to, void __user *from, int size) | |
344 | { | |
6e21aec3 | 345 | return copy_from_user(to, from, size); |
1da177e4 LT |
346 | } |
347 | ||
348 | int clear_user_proc(void __user *buf, int size) | |
349 | { | |
6e21aec3 | 350 | return clear_user(buf, size); |
1da177e4 LT |
351 | } |
352 | ||
353 | int strlen_user_proc(char __user *str) | |
354 | { | |
6e21aec3 | 355 | return strlen_user(str); |
1da177e4 LT |
356 | } |
357 | ||
358 | int smp_sigio_handler(void) | |
359 | { | |
360 | #ifdef CONFIG_SMP | |
361 | int cpu = current_thread->cpu; | |
362 | IPI_handler(cpu); | |
ba180fd4 | 363 | if (cpu != 0) |
6e21aec3 | 364 | return 1; |
1da177e4 | 365 | #endif |
6e21aec3 | 366 | return 0; |
1da177e4 LT |
367 | } |
368 | ||
1da177e4 LT |
369 | int cpu(void) |
370 | { | |
6e21aec3 | 371 | return current_thread->cpu; |
1da177e4 LT |
372 | } |
373 | ||
374 | static atomic_t using_sysemu = ATOMIC_INIT(0); | |
375 | int sysemu_supported; | |
376 | ||
377 | void set_using_sysemu(int value) | |
378 | { | |
379 | if (value > sysemu_supported) | |
380 | return; | |
381 | atomic_set(&using_sysemu, value); | |
382 | } | |
383 | ||
384 | int get_using_sysemu(void) | |
385 | { | |
386 | return atomic_read(&using_sysemu); | |
387 | } | |
388 | ||
389 | static int proc_read_sysemu(char *buf, char **start, off_t offset, int size,int *eof, void *data) | |
390 | { | |
ba180fd4 JD |
391 | if (snprintf(buf, size, "%d\n", get_using_sysemu()) < size) |
392 | /* No overflow */ | |
1da177e4 LT |
393 | *eof = 1; |
394 | ||
395 | return strlen(buf); | |
396 | } | |
397 | ||
4d338e1a | 398 | static int proc_write_sysemu(struct file *file,const char __user *buf, unsigned long count,void *data) |
1da177e4 LT |
399 | { |
400 | char tmp[2]; | |
401 | ||
402 | if (copy_from_user(tmp, buf, 1)) | |
403 | return -EFAULT; | |
404 | ||
405 | if (tmp[0] >= '0' && tmp[0] <= '2') | |
406 | set_using_sysemu(tmp[0] - '0'); | |
ba180fd4 JD |
407 | /* We use the first char, but pretend to write everything */ |
408 | return count; | |
1da177e4 LT |
409 | } |
410 | ||
411 | int __init make_proc_sysemu(void) | |
412 | { | |
413 | struct proc_dir_entry *ent; | |
414 | if (!sysemu_supported) | |
415 | return 0; | |
416 | ||
417 | ent = create_proc_entry("sysemu", 0600, &proc_root); | |
418 | ||
419 | if (ent == NULL) | |
420 | { | |
30f417c6 | 421 | printk(KERN_WARNING "Failed to register /proc/sysemu\n"); |
6e21aec3 | 422 | return 0; |
1da177e4 LT |
423 | } |
424 | ||
425 | ent->read_proc = proc_read_sysemu; | |
426 | ent->write_proc = proc_write_sysemu; | |
427 | ||
428 | return 0; | |
429 | } | |
430 | ||
431 | late_initcall(make_proc_sysemu); | |
432 | ||
433 | int singlestepping(void * t) | |
434 | { | |
435 | struct task_struct *task = t ? t : current; | |
436 | ||
437 | if ( ! (task->ptrace & PT_DTRACE) ) | |
ba180fd4 | 438 | return 0; |
1da177e4 LT |
439 | |
440 | if (task->thread.singlestep_syscall) | |
ba180fd4 | 441 | return 1; |
1da177e4 LT |
442 | |
443 | return 2; | |
444 | } | |
445 | ||
b8bd0220 BS |
446 | /* |
447 | * Only x86 and x86_64 have an arch_align_stack(). | |
448 | * All other arches have "#define arch_align_stack(x) (x)" | |
449 | * in their asm/system.h | |
450 | * As this is included in UML from asm-um/system-generic.h, | |
451 | * we can use it to behave as the subarch does. | |
452 | */ | |
453 | #ifndef arch_align_stack | |
1da177e4 LT |
454 | unsigned long arch_align_stack(unsigned long sp) |
455 | { | |
8f80e946 | 456 | if (!(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space) |
1da177e4 LT |
457 | sp -= get_random_int() % 8192; |
458 | return sp & ~0xf; | |
459 | } | |
b8bd0220 | 460 | #endif |