[PATCH] uml: file renaming
[linux-2.6.git] / arch / um / kernel / process.c
1 /*
2  * Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.com)
3  * Copyright 2003 PathScale, Inc.
4  * Licensed under the GPL
5  */
6
7 #include "linux/kernel.h"
8 #include "linux/sched.h"
9 #include "linux/interrupt.h"
10 #include "linux/string.h"
11 #include "linux/mm.h"
12 #include "linux/slab.h"
13 #include "linux/utsname.h"
14 #include "linux/fs.h"
15 #include "linux/utime.h"
16 #include "linux/smp_lock.h"
17 #include "linux/module.h"
18 #include "linux/init.h"
19 #include "linux/capability.h"
20 #include "linux/vmalloc.h"
21 #include "linux/spinlock.h"
22 #include "linux/proc_fs.h"
23 #include "linux/ptrace.h"
24 #include "linux/random.h"
25 #include "linux/personality.h"
26 #include "asm/unistd.h"
27 #include "asm/mman.h"
28 #include "asm/segment.h"
29 #include "asm/stat.h"
30 #include "asm/pgtable.h"
31 #include "asm/processor.h"
32 #include "asm/tlbflush.h"
33 #include "asm/uaccess.h"
34 #include "asm/user.h"
35 #include "user_util.h"
36 #include "kern_util.h"
37 #include "kern.h"
38 #include "signal_kern.h"
39 #include "init.h"
40 #include "irq_user.h"
41 #include "mem_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
50 /* This is a per-cpu array.  A processor only modifies its entry and it only
51  * cares about its entry, so it's OK if another processor is modifying its
52  * entry.
53  */
54 struct cpu_task cpu_tasks[NR_CPUS] = { [0 ... NR_CPUS - 1] = { -1, NULL } };
55
56 int external_pid(void *t)
57 {
58         struct task_struct *task = t ? t : current;
59
60         return(CHOOSE_MODE_PROC(external_pid_tt, external_pid_skas, task));
61 }
62
63 int pid_to_processor_id(int pid)
64 {
65         int i;
66
67         for(i = 0; i < ncpus; i++){
68                 if(cpu_tasks[i].pid == pid) return(i);
69         }
70         return(-1);
71 }
72
73 void free_stack(unsigned long stack, int order)
74 {
75         free_pages(stack, order);
76 }
77
78 unsigned long alloc_stack(int order, int atomic)
79 {
80         unsigned long page;
81         gfp_t flags = GFP_KERNEL;
82
83         if (atomic)
84                 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
92 int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
93 {
94         int pid;
95
96         current->thread.request.u.thread.proc = fn;
97         current->thread.request.u.thread.arg = arg;
98         pid = do_fork(CLONE_VM | CLONE_UNTRACED | flags, 0,
99                       &current->thread.regs, 0, NULL, NULL);
100         if(pid < 0)
101                 panic("do_fork failed in kernel_thread, errno = %d", pid);
102         return(pid);
103 }
104
105 void set_current(void *t)
106 {
107         struct task_struct *task = t;
108
109         cpu_tasks[task_thread_info(task)->cpu] = ((struct cpu_task)
110                 { external_pid(task), task });
111 }
112
113 void *_switch_to(void *prev, void *next, void *last)
114 {
115         struct task_struct *from = prev;
116         struct task_struct *to= next;
117
118         to->thread.prev_sched = from;
119         set_current(to);
120
121         do {
122                 current->thread.saved_task = NULL ;
123                 CHOOSE_MODE_PROC(switch_to_tt, switch_to_skas, prev, next);
124                 if(current->thread.saved_task)
125                         show_regs(&(current->thread.regs));
126                 next= current->thread.saved_task;
127                 prev= current;
128         } while(current->thread.saved_task);
129
130         return(current->thread.prev_sched);
131
132 }
133
134 void interrupt_end(void)
135 {
136         if(need_resched()) schedule();
137         if(test_tsk_thread_flag(current, TIF_SIGPENDING)) do_signal();
138 }
139
140 void release_thread(struct task_struct *task)
141 {
142         CHOOSE_MODE(release_thread_tt(task), release_thread_skas(task));
143 }
144
145 void exit_thread(void)
146 {
147         unprotect_stack((unsigned long) current_thread);
148 }
149
150 void *get_current(void)
151 {
152         return(current);
153 }
154
155 int copy_thread(int nr, unsigned long clone_flags, unsigned long sp,
156                 unsigned long stack_top, struct task_struct * p,
157                 struct pt_regs *regs)
158 {
159         int ret;
160
161         p->thread = (struct thread_struct) INIT_THREAD;
162         ret = CHOOSE_MODE_PROC(copy_thread_tt, copy_thread_skas, nr,
163                                 clone_flags, sp, stack_top, p, regs);
164
165         if (ret || !current->thread.forking)
166                 goto out;
167
168         clear_flushed_tls(p);
169
170         /*
171          * Set a new TLS for the child thread?
172          */
173         if (clone_flags & CLONE_SETTLS)
174                 ret = arch_copy_tls(p);
175
176 out:
177         return ret;
178 }
179
180 void initial_thread_cb(void (*proc)(void *), void *arg)
181 {
182         int save_kmalloc_ok = kmalloc_ok;
183
184         kmalloc_ok = 0;
185         CHOOSE_MODE_PROC(initial_thread_cb_tt, initial_thread_cb_skas, proc,
186                          arg);
187         kmalloc_ok = save_kmalloc_ok;
188 }
189
190 unsigned long stack_sp(unsigned long page)
191 {
192         return(page + PAGE_SIZE - sizeof(void *));
193 }
194
195 int current_pid(void)
196 {
197         return(current->pid);
198 }
199
200 void default_idle(void)
201 {
202         CHOOSE_MODE(uml_idle_timer(), (void) 0);
203
204         while(1){
205                 /* endless idle loop with no priority at all */
206
207                 /*
208                  * although we are an idle CPU, we do not want to
209                  * get into the scheduler unnecessarily.
210                  */
211                 if(need_resched())
212                         schedule();
213
214                 idle_sleep(10);
215         }
216 }
217
218 void cpu_idle(void)
219 {
220         CHOOSE_MODE(init_idle_tt(), init_idle_skas());
221 }
222
223 int page_size(void)
224 {
225         return(PAGE_SIZE);
226 }
227
228 void *um_virt_to_phys(struct task_struct *task, unsigned long addr,
229                       pte_t *pte_out)
230 {
231         pgd_t *pgd;
232         pud_t *pud;
233         pmd_t *pmd;
234         pte_t *pte;
235         pte_t ptent;
236
237         if(task->mm == NULL)
238                 return(ERR_PTR(-EINVAL));
239         pgd = pgd_offset(task->mm, addr);
240         if(!pgd_present(*pgd))
241                 return(ERR_PTR(-EINVAL));
242
243         pud = pud_offset(pgd, addr);
244         if(!pud_present(*pud))
245                 return(ERR_PTR(-EINVAL));
246
247         pmd = pmd_offset(pud, addr);
248         if(!pmd_present(*pmd))
249                 return(ERR_PTR(-EINVAL));
250
251         pte = pte_offset_kernel(pmd, addr);
252         ptent = *pte;
253         if(!pte_present(ptent))
254                 return(ERR_PTR(-EINVAL));
255
256         if(pte_out != NULL)
257                 *pte_out = ptent;
258         return((void *) (pte_val(ptent) & PAGE_MASK) + (addr & ~PAGE_MASK));
259 }
260
261 char *current_cmd(void)
262 {
263 #if defined(CONFIG_SMP) || defined(CONFIG_HIGHMEM)
264         return("(Unknown)");
265 #else
266         void *addr = um_virt_to_phys(current, current->mm->arg_start, NULL);
267         return IS_ERR(addr) ? "(Unknown)": __va((unsigned long) addr);
268 #endif
269 }
270
271 void force_sigbus(void)
272 {
273         printk(KERN_ERR "Killing pid %d because of a lack of memory\n",
274                current->pid);
275         lock_kernel();
276         sigaddset(&current->pending.signal, SIGBUS);
277         recalc_sigpending();
278         current->flags |= PF_SIGNALED;
279         do_exit(SIGBUS | 0x80);
280 }
281
282 void dump_thread(struct pt_regs *regs, struct user *u)
283 {
284 }
285
286 void enable_hlt(void)
287 {
288         panic("enable_hlt");
289 }
290
291 EXPORT_SYMBOL(enable_hlt);
292
293 void disable_hlt(void)
294 {
295         panic("disable_hlt");
296 }
297
298 EXPORT_SYMBOL(disable_hlt);
299
300 void *um_kmalloc(int size)
301 {
302         return kmalloc(size, GFP_KERNEL);
303 }
304
305 void *um_kmalloc_atomic(int size)
306 {
307         return kmalloc(size, GFP_ATOMIC);
308 }
309
310 void *um_vmalloc(int size)
311 {
312         return vmalloc(size);
313 }
314
315 void *um_vmalloc_atomic(int size)
316 {
317         return __vmalloc(size, GFP_ATOMIC | __GFP_HIGHMEM, PAGE_KERNEL);
318 }
319
320 int __cant_sleep(void) {
321         return in_atomic() || irqs_disabled() || in_interrupt();
322         /* Is in_interrupt() really needed? */
323 }
324
325 unsigned long get_fault_addr(void)
326 {
327         return((unsigned long) current->thread.fault_addr);
328 }
329
330 EXPORT_SYMBOL(get_fault_addr);
331
332 void not_implemented(void)
333 {
334         printk(KERN_DEBUG "Something isn't implemented in here\n");
335 }
336
337 EXPORT_SYMBOL(not_implemented);
338
339 int user_context(unsigned long sp)
340 {
341         unsigned long stack;
342
343         stack = sp & (PAGE_MASK << CONFIG_KERNEL_STACK_ORDER);
344         return(stack != (unsigned long) current_thread);
345 }
346
347 extern exitcall_t __uml_exitcall_begin, __uml_exitcall_end;
348
349 void do_uml_exitcalls(void)
350 {
351         exitcall_t *call;
352
353         call = &__uml_exitcall_end;
354         while (--call >= &__uml_exitcall_begin)
355                 (*call)();
356 }
357
358 char *uml_strdup(char *string)
359 {
360         return kstrdup(string, GFP_KERNEL);
361 }
362
363 int copy_to_user_proc(void __user *to, void *from, int size)
364 {
365         return(copy_to_user(to, from, size));
366 }
367
368 int copy_from_user_proc(void *to, void __user *from, int size)
369 {
370         return(copy_from_user(to, from, size));
371 }
372
373 int clear_user_proc(void __user *buf, int size)
374 {
375         return(clear_user(buf, size));
376 }
377
378 int strlen_user_proc(char __user *str)
379 {
380         return(strlen_user(str));
381 }
382
383 int smp_sigio_handler(void)
384 {
385 #ifdef CONFIG_SMP
386         int cpu = current_thread->cpu;
387         IPI_handler(cpu);
388         if(cpu != 0)
389                 return(1);
390 #endif
391         return(0);
392 }
393
394 int cpu(void)
395 {
396         return(current_thread->cpu);
397 }
398
399 static atomic_t using_sysemu = ATOMIC_INIT(0);
400 int sysemu_supported;
401
402 void set_using_sysemu(int value)
403 {
404         if (value > sysemu_supported)
405                 return;
406         atomic_set(&using_sysemu, value);
407 }
408
409 int get_using_sysemu(void)
410 {
411         return atomic_read(&using_sysemu);
412 }
413
414 static int proc_read_sysemu(char *buf, char **start, off_t offset, int size,int *eof, void *data)
415 {
416         if (snprintf(buf, size, "%d\n", get_using_sysemu()) < size) /*No overflow*/
417                 *eof = 1;
418
419         return strlen(buf);
420 }
421
422 static int proc_write_sysemu(struct file *file,const char __user *buf, unsigned long count,void *data)
423 {
424         char tmp[2];
425
426         if (copy_from_user(tmp, buf, 1))
427                 return -EFAULT;
428
429         if (tmp[0] >= '0' && tmp[0] <= '2')
430                 set_using_sysemu(tmp[0] - '0');
431         return count; /*We use the first char, but pretend to write everything*/
432 }
433
434 int __init make_proc_sysemu(void)
435 {
436         struct proc_dir_entry *ent;
437         if (!sysemu_supported)
438                 return 0;
439
440         ent = create_proc_entry("sysemu", 0600, &proc_root);
441
442         if (ent == NULL)
443         {
444                 printk(KERN_WARNING "Failed to register /proc/sysemu\n");
445                 return(0);
446         }
447
448         ent->read_proc  = proc_read_sysemu;
449         ent->write_proc = proc_write_sysemu;
450
451         return 0;
452 }
453
454 late_initcall(make_proc_sysemu);
455
456 int singlestepping(void * t)
457 {
458         struct task_struct *task = t ? t : current;
459
460         if ( ! (task->ptrace & PT_DTRACE) )
461                 return(0);
462
463         if (task->thread.singlestep_syscall)
464                 return(1);
465
466         return 2;
467 }
468
469 /*
470  * Only x86 and x86_64 have an arch_align_stack().
471  * All other arches have "#define arch_align_stack(x) (x)"
472  * in their asm/system.h
473  * As this is included in UML from asm-um/system-generic.h,
474  * we can use it to behave as the subarch does.
475  */
476 #ifndef arch_align_stack
477 unsigned long arch_align_stack(unsigned long sp)
478 {
479         if (!(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space)
480                 sp -= get_random_int() % 8192;
481         return sp & ~0xf;
482 }
483 #endif