upgrade to linux 2.6.10-1.12_FC2
[linux-2.6.git] / arch / um / kernel / process_kern.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/config.h"
8 #include "linux/kernel.h"
9 #include "linux/sched.h"
10 #include "linux/interrupt.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/vs_cvirt.h"
23 #include "linux/proc_fs.h"
24 #include "linux/ptrace.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 "signal_user.h"
39 #include "init.h"
40 #include "irq_user.h"
41 #include "mem_user.h"
42 #include "time_user.h"
43 #include "tlb.h"
44 #include "frame_kern.h"
45 #include "sigcontext.h"
46 #include "2_5compat.h"
47 #include "os.h"
48 #include "mode.h"
49 #include "mode_kern.h"
50 #include "choose-mode.h"
51
52 /* This is a per-cpu array.  A processor only modifies its entry and it only
53  * cares about its entry, so it's OK if another processor is modifying its
54  * entry.
55  */
56 struct cpu_task cpu_tasks[NR_CPUS] = { [0 ... NR_CPUS - 1] = { -1, NULL } };
57
58 struct task_struct *get_task(int pid, int require)
59 {
60         struct task_struct *ret;
61
62         read_lock(&tasklist_lock);
63         ret = find_task_by_pid(pid);
64         read_unlock(&tasklist_lock);
65
66         if(require && (ret == NULL)) panic("get_task couldn't find a task\n");
67         return(ret);
68 }
69
70 int external_pid(void *t)
71 {
72         struct task_struct *task = t ? t : current;
73
74         return(CHOOSE_MODE_PROC(external_pid_tt, external_pid_skas, task));
75 }
76
77 int pid_to_processor_id(int pid)
78 {
79         int i;
80
81         for(i = 0; i < ncpus; i++){
82                 if(cpu_tasks[i].pid == pid) return(i);
83         }
84         return(-1);
85 }
86
87 void free_stack(unsigned long stack, int order)
88 {
89         free_pages(stack, order);
90 }
91
92 unsigned long alloc_stack(int order, int atomic)
93 {
94         unsigned long page;
95         int flags = GFP_KERNEL;
96
97         if(atomic) flags |= GFP_ATOMIC;
98         page = __get_free_pages(flags, order);
99         if(page == 0)
100                 return(0);
101         stack_protections(page);
102         return(page);
103 }
104
105 int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
106 {
107         int pid;
108
109         current->thread.request.u.thread.proc = fn;
110         current->thread.request.u.thread.arg = arg;
111         pid = do_fork(CLONE_VM | CLONE_UNTRACED | flags, 0, NULL, 0, NULL,
112                       NULL);
113         if(pid < 0)
114                 panic("do_fork failed in kernel_thread, errno = %d", pid);
115         return(pid);
116 }
117
118 void switch_mm(struct mm_struct *prev, struct mm_struct *next, 
119                struct task_struct *tsk)
120 {
121         int cpu = smp_processor_id();
122
123         if (prev != next) 
124                 cpu_clear(cpu, prev->cpu_vm_mask);
125         cpu_set(cpu, next->cpu_vm_mask);
126 }
127
128 void set_current(void *t)
129 {
130         struct task_struct *task = t;
131
132         cpu_tasks[task->thread_info->cpu] = ((struct cpu_task) 
133                 { external_pid(task), task });
134 }
135
136 void *_switch_to(void *prev, void *next, void *last)
137 {
138         return(CHOOSE_MODE(switch_to_tt(prev, next), 
139                            switch_to_skas(prev, next)));
140 }
141
142 void interrupt_end(void)
143 {
144         if(need_resched()) schedule();
145         if(test_tsk_thread_flag(current, TIF_SIGPENDING)) do_signal();
146 }
147
148 void release_thread(struct task_struct *task)
149 {
150         CHOOSE_MODE(release_thread_tt(task), release_thread_skas(task));
151 }
152  
153 void exit_thread(void)
154 {
155         CHOOSE_MODE(exit_thread_tt(), exit_thread_skas());
156         unprotect_stack((unsigned long) current_thread);
157 }
158  
159 void *get_current(void)
160 {
161         return(current);
162 }
163
164 void prepare_to_copy(struct task_struct *tsk)
165 {
166 }
167
168 int copy_thread(int nr, unsigned long clone_flags, unsigned long sp,
169                 unsigned long stack_top, struct task_struct * p, 
170                 struct pt_regs *regs)
171 {
172         p->thread = (struct thread_struct) INIT_THREAD;
173         return(CHOOSE_MODE_PROC(copy_thread_tt, copy_thread_skas, nr, 
174                                 clone_flags, sp, stack_top, p, regs));
175 }
176
177 void initial_thread_cb(void (*proc)(void *), void *arg)
178 {
179         int save_kmalloc_ok = kmalloc_ok;
180
181         kmalloc_ok = 0;
182         CHOOSE_MODE_PROC(initial_thread_cb_tt, initial_thread_cb_skas, proc, 
183                          arg);
184         kmalloc_ok = save_kmalloc_ok;
185 }
186  
187 unsigned long stack_sp(unsigned long page)
188 {
189         return(page + PAGE_SIZE - sizeof(void *));
190 }
191
192 int current_pid(void)
193 {
194         return(current->pid);
195 }
196
197 void default_idle(void)
198 {
199         uml_idle_timer();
200
201         atomic_inc(&init_mm.mm_count);
202         current->mm = &init_mm;
203         current->active_mm = &init_mm;
204
205         while(1){
206                 /* endless idle loop with no priority at all */
207                 SET_PRI(current);
208
209                 /*
210                  * although we are an idle CPU, we do not want to
211                  * get into the scheduler unnecessarily.
212                  */
213                 if(need_resched())
214                         schedule();
215                 
216                 idle_sleep(10);
217         }
218 }
219
220 void cpu_idle(void)
221 {
222         CHOOSE_MODE(init_idle_tt(), init_idle_skas());
223 }
224
225 int page_size(void)
226 {
227         return(PAGE_SIZE);
228 }
229
230 unsigned long page_mask(void)
231 {
232         return(PAGE_MASK);
233 }
234
235 void *um_virt_to_phys(struct task_struct *task, unsigned long addr, 
236                       pte_t *pte_out)
237 {
238         pgd_t *pgd;
239         pmd_t *pmd;
240         pte_t *pte;
241
242         if(task->mm == NULL) 
243                 return(ERR_PTR(-EINVAL));
244         pgd = pgd_offset(task->mm, addr);
245         pmd = pmd_offset(pgd, addr);
246         if(!pmd_present(*pmd)) 
247                 return(ERR_PTR(-EINVAL));
248         pte = pte_offset_kernel(pmd, addr);
249         if(!pte_present(*pte)) 
250                 return(ERR_PTR(-EINVAL));
251         if(pte_out != NULL)
252                 *pte_out = *pte;
253         return((void *) (pte_val(*pte) & PAGE_MASK) + (addr & ~PAGE_MASK));
254 }
255
256 char *current_cmd(void)
257 {
258 #if defined(CONFIG_SMP) || defined(CONFIG_HIGHMEM)
259         return("(Unknown)");
260 #else
261         void *addr = um_virt_to_phys(current, current->mm->arg_start, NULL);
262         return IS_ERR(addr) ? "(Unknown)": __va((unsigned long) addr);
263 #endif
264 }
265
266 void force_sigbus(void)
267 {
268         printk(KERN_ERR "Killing pid %d because of a lack of memory\n", 
269                current->pid);
270         lock_kernel();
271         sigaddset(&current->pending.signal, SIGBUS);
272         recalc_sigpending();
273         current->flags |= PF_SIGNALED;
274         do_exit(SIGBUS | 0x80);
275 }
276
277 void dump_thread(struct pt_regs *regs, struct user *u)
278 {
279 }
280
281 void enable_hlt(void)
282 {
283         panic("enable_hlt");
284 }
285
286 EXPORT_SYMBOL(enable_hlt);
287
288 void disable_hlt(void)
289 {
290         panic("disable_hlt");
291 }
292
293 EXPORT_SYMBOL(disable_hlt);
294
295 extern int signal_frame_size;
296
297 void *um_kmalloc(int size)
298 {
299         return(kmalloc(size, GFP_KERNEL));
300 }
301
302 void *um_kmalloc_atomic(int size)
303 {
304         return(kmalloc(size, GFP_ATOMIC));
305 }
306
307 void *um_vmalloc(int size)
308 {
309         return(vmalloc(size));
310 }
311
312 unsigned long get_fault_addr(void)
313 {
314         return((unsigned long) current->thread.fault_addr);
315 }
316
317 EXPORT_SYMBOL(get_fault_addr);
318
319 void not_implemented(void)
320 {
321         printk(KERN_DEBUG "Something isn't implemented in here\n");
322 }
323
324 EXPORT_SYMBOL(not_implemented);
325
326 int user_context(unsigned long sp)
327 {
328         unsigned long stack;
329
330         stack = sp & (PAGE_MASK << CONFIG_KERNEL_STACK_ORDER);
331         return(stack != (unsigned long) current_thread);
332 }
333
334 extern void remove_umid_dir(void);
335
336 __uml_exitcall(remove_umid_dir);
337
338 extern exitcall_t __uml_exitcall_begin, __uml_exitcall_end;
339
340 void do_uml_exitcalls(void)
341 {
342         exitcall_t *call;
343
344         call = &__uml_exitcall_end;
345         while (--call >= &__uml_exitcall_begin)
346                 (*call)();
347 }
348
349 char *uml_strdup(char *string)
350 {
351         char *new;
352
353         new = kmalloc(strlen(string) + 1, GFP_KERNEL);
354         if(new == NULL) return(NULL);
355         strcpy(new, string);
356         return(new);
357 }
358
359 void *get_init_task(void)
360 {
361         return(&init_thread_union.thread_info.task);
362 }
363
364 int copy_to_user_proc(void *to, void *from, int size)
365 {
366         return(copy_to_user(to, from, size));
367 }
368
369 int copy_from_user_proc(void *to, void *from, int size)
370 {
371         return(copy_from_user(to, from, size));
372 }
373
374 int clear_user_proc(void *buf, int size)
375 {
376         return(clear_user(buf, size));
377 }
378
379 int strlen_user_proc(char *str)
380 {
381         return(strlen_user(str));
382 }
383
384 int smp_sigio_handler(void)
385 {
386 #ifdef CONFIG_SMP
387         int cpu = current_thread->cpu;
388         IPI_handler(cpu);
389         if(cpu != 0)
390                 return(1);
391 #endif
392         return(0);
393 }
394
395 int um_in_interrupt(void)
396 {
397         return(in_interrupt());
398 }
399
400 int cpu(void)
401 {
402         return(current_thread->cpu);
403 }
404
405 static atomic_t using_sysemu = ATOMIC_INIT(0);
406 int sysemu_supported;
407
408 void set_using_sysemu(int value)
409 {
410         atomic_set(&using_sysemu, sysemu_supported && value);
411 }
412
413 int get_using_sysemu(void)
414 {
415         return atomic_read(&using_sysemu);
416 }
417
418 static int proc_read_sysemu(char *buf, char **start, off_t offset, int size,int *eof, void *data)
419 {
420         if (snprintf(buf, size, "%d\n", get_using_sysemu()) < size) /*No overflow*/
421                 *eof = 1;
422
423         return strlen(buf);
424 }
425
426 static int proc_write_sysemu(struct file *file,const char *buf, unsigned long count,void *data)
427 {
428         char tmp[2];
429
430         if (copy_from_user(tmp, buf, 1))
431                 return -EFAULT;
432
433         if (tmp[0] == '0' || tmp[0] == '1')
434                 set_using_sysemu(tmp[0] - '0');
435         return count; /*We use the first char, but pretend to write everything*/
436 }
437
438 int __init make_proc_sysemu(void)
439 {
440         struct proc_dir_entry *ent;
441         if (!sysemu_supported)
442                 return 0;
443
444         ent = create_proc_entry("sysemu", 0600, &proc_root);
445
446         if (ent == NULL)
447         {
448                 printk("Failed to register /proc/sysemu\n");
449                 return(0);
450         }
451
452         ent->read_proc  = proc_read_sysemu;
453         ent->write_proc = proc_write_sysemu;
454
455         return 0;
456 }
457
458 late_initcall(make_proc_sysemu);
459
460 int singlestepping(void * t)
461 {
462         struct task_struct *task = t ? t : current;
463
464         if ( ! (task->ptrace & PT_DTRACE) )
465                 return(0);
466
467         if (task->thread.singlestep_syscall)
468                 return(0);
469
470         return 1;
471 }
472
473 /*
474  * Overrides for Emacs so that we follow Linus's tabbing style.
475  * Emacs will notice this stuff at the end of the file and automatically
476  * adjust the settings for this buffer only.  This must remain at the end
477  * of the file.
478  * ---------------------------------------------------------------------------
479  * Local variables:
480  * c-file-style: "linux"
481  * End:
482  */