Linux 2.6.17.7
[linux/fpc-iii.git] / arch / um / kernel / process_kern.c
blobf6a5a502120beb1d1027684d3528df4624ee9d81
1 /*
2 * Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.com)
3 * Copyright 2003 PathScale, Inc.
4 * Licensed under the GPL
5 */
7 #include "linux/config.h"
8 #include "linux/kernel.h"
9 #include "linux/sched.h"
10 #include "linux/interrupt.h"
11 #include "linux/string.h"
12 #include "linux/mm.h"
13 #include "linux/slab.h"
14 #include "linux/utsname.h"
15 #include "linux/fs.h"
16 #include "linux/utime.h"
17 #include "linux/smp_lock.h"
18 #include "linux/module.h"
19 #include "linux/init.h"
20 #include "linux/capability.h"
21 #include "linux/vmalloc.h"
22 #include "linux/spinlock.h"
23 #include "linux/proc_fs.h"
24 #include "linux/ptrace.h"
25 #include "linux/random.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"
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.
54 struct cpu_task cpu_tasks[NR_CPUS] = { [0 ... NR_CPUS - 1] = { -1, NULL } };
56 int external_pid(void *t)
58 struct task_struct *task = t ? t : current;
60 return(CHOOSE_MODE_PROC(external_pid_tt, external_pid_skas, task));
63 int pid_to_processor_id(int pid)
65 int i;
67 for(i = 0; i < ncpus; i++){
68 if(cpu_tasks[i].pid == pid) return(i);
70 return(-1);
73 void free_stack(unsigned long stack, int order)
75 free_pages(stack, order);
78 unsigned long alloc_stack(int order, int atomic)
80 unsigned long page;
81 gfp_t flags = GFP_KERNEL;
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);
92 int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
94 int pid;
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);
105 void set_current(void *t)
107 struct task_struct *task = t;
109 cpu_tasks[task_thread_info(task)->cpu] = ((struct cpu_task)
110 { external_pid(task), task });
113 void *_switch_to(void *prev, void *next, void *last)
115 struct task_struct *from = prev;
116 struct task_struct *to= next;
118 to->thread.prev_sched = from;
119 set_current(to);
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);
130 return(current->thread.prev_sched);
134 void interrupt_end(void)
136 if(need_resched()) schedule();
137 if(test_tsk_thread_flag(current, TIF_SIGPENDING)) do_signal();
140 void release_thread(struct task_struct *task)
142 CHOOSE_MODE(release_thread_tt(task), release_thread_skas(task));
145 void exit_thread(void)
147 unprotect_stack((unsigned long) current_thread);
150 void *get_current(void)
152 return(current);
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)
159 int ret;
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);
165 if (ret || !current->thread.forking)
166 goto out;
168 clear_flushed_tls(p);
171 * Set a new TLS for the child thread?
173 if (clone_flags & CLONE_SETTLS)
174 ret = arch_copy_tls(p);
176 out:
177 return ret;
180 void initial_thread_cb(void (*proc)(void *), void *arg)
182 int save_kmalloc_ok = kmalloc_ok;
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;
190 unsigned long stack_sp(unsigned long page)
192 return(page + PAGE_SIZE - sizeof(void *));
195 int current_pid(void)
197 return(current->pid);
200 void default_idle(void)
202 CHOOSE_MODE(uml_idle_timer(), (void) 0);
204 while(1){
205 /* endless idle loop with no priority at all */
208 * although we are an idle CPU, we do not want to
209 * get into the scheduler unnecessarily.
211 if(need_resched())
212 schedule();
214 idle_sleep(10);
218 void cpu_idle(void)
220 CHOOSE_MODE(init_idle_tt(), init_idle_skas());
223 int page_size(void)
225 return(PAGE_SIZE);
228 void *um_virt_to_phys(struct task_struct *task, unsigned long addr,
229 pte_t *pte_out)
231 pgd_t *pgd;
232 pud_t *pud;
233 pmd_t *pmd;
234 pte_t *pte;
235 pte_t ptent;
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));
243 pud = pud_offset(pgd, addr);
244 if(!pud_present(*pud))
245 return(ERR_PTR(-EINVAL));
247 pmd = pmd_offset(pud, addr);
248 if(!pmd_present(*pmd))
249 return(ERR_PTR(-EINVAL));
251 pte = pte_offset_kernel(pmd, addr);
252 ptent = *pte;
253 if(!pte_present(ptent))
254 return(ERR_PTR(-EINVAL));
256 if(pte_out != NULL)
257 *pte_out = ptent;
258 return((void *) (pte_val(ptent) & PAGE_MASK) + (addr & ~PAGE_MASK));
261 char *current_cmd(void)
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
271 void force_sigbus(void)
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);
282 void dump_thread(struct pt_regs *regs, struct user *u)
286 void enable_hlt(void)
288 panic("enable_hlt");
291 EXPORT_SYMBOL(enable_hlt);
293 void disable_hlt(void)
295 panic("disable_hlt");
298 EXPORT_SYMBOL(disable_hlt);
300 void *um_kmalloc(int size)
302 return kmalloc(size, GFP_KERNEL);
305 void *um_kmalloc_atomic(int size)
307 return kmalloc(size, GFP_ATOMIC);
310 void *um_vmalloc(int size)
312 return vmalloc(size);
315 void *um_vmalloc_atomic(int size)
317 return __vmalloc(size, GFP_ATOMIC | __GFP_HIGHMEM, PAGE_KERNEL);
320 int __cant_sleep(void) {
321 return in_atomic() || irqs_disabled() || in_interrupt();
322 /* Is in_interrupt() really needed? */
325 unsigned long get_fault_addr(void)
327 return((unsigned long) current->thread.fault_addr);
330 EXPORT_SYMBOL(get_fault_addr);
332 void not_implemented(void)
334 printk(KERN_DEBUG "Something isn't implemented in here\n");
337 EXPORT_SYMBOL(not_implemented);
339 int user_context(unsigned long sp)
341 unsigned long stack;
343 stack = sp & (PAGE_MASK << CONFIG_KERNEL_STACK_ORDER);
344 return(stack != (unsigned long) current_thread);
347 extern exitcall_t __uml_exitcall_begin, __uml_exitcall_end;
349 void do_uml_exitcalls(void)
351 exitcall_t *call;
353 call = &__uml_exitcall_end;
354 while (--call >= &__uml_exitcall_begin)
355 (*call)();
358 char *uml_strdup(char *string)
360 return kstrdup(string, GFP_KERNEL);
363 int copy_to_user_proc(void __user *to, void *from, int size)
365 return(copy_to_user(to, from, size));
368 int copy_from_user_proc(void *to, void __user *from, int size)
370 return(copy_from_user(to, from, size));
373 int clear_user_proc(void __user *buf, int size)
375 return(clear_user(buf, size));
378 int strlen_user_proc(char __user *str)
380 return(strlen_user(str));
383 int smp_sigio_handler(void)
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);
394 int cpu(void)
396 return(current_thread->cpu);
399 static atomic_t using_sysemu = ATOMIC_INIT(0);
400 int sysemu_supported;
402 void set_using_sysemu(int value)
404 if (value > sysemu_supported)
405 return;
406 atomic_set(&using_sysemu, value);
409 int get_using_sysemu(void)
411 return atomic_read(&using_sysemu);
414 static int proc_read_sysemu(char *buf, char **start, off_t offset, int size,int *eof, void *data)
416 if (snprintf(buf, size, "%d\n", get_using_sysemu()) < size) /*No overflow*/
417 *eof = 1;
419 return strlen(buf);
422 static int proc_write_sysemu(struct file *file,const char __user *buf, unsigned long count,void *data)
424 char tmp[2];
426 if (copy_from_user(tmp, buf, 1))
427 return -EFAULT;
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*/
434 int __init make_proc_sysemu(void)
436 struct proc_dir_entry *ent;
437 if (!sysemu_supported)
438 return 0;
440 ent = create_proc_entry("sysemu", 0600, &proc_root);
442 if (ent == NULL)
444 printk(KERN_WARNING "Failed to register /proc/sysemu\n");
445 return(0);
448 ent->read_proc = proc_read_sysemu;
449 ent->write_proc = proc_write_sysemu;
451 return 0;
454 late_initcall(make_proc_sysemu);
456 int singlestepping(void * t)
458 struct task_struct *task = t ? t : current;
460 if ( ! (task->ptrace & PT_DTRACE) )
461 return(0);
463 if (task->thread.singlestep_syscall)
464 return(1);
466 return 2;
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.
476 #ifndef arch_align_stack
477 unsigned long arch_align_stack(unsigned long sp)
479 if (randomize_va_space)
480 sp -= get_random_int() % 8192;
481 return sp & ~0xf;
483 #endif