ia64/linux-2.6.18-xen.hg

view arch/m68k/kernel/process.c @ 452:c7ed6fe5dca0

kexec: dont initialise regions in reserve_memory()

There is no need to initialise efi_memmap_res and boot_param_res in
reserve_memory() for the initial xen domain as it is done in
machine_kexec_setup_resources() using values from the kexec hypercall.

Signed-off-by: Simon Horman <horms@verge.net.au>
author Keir Fraser <keir.fraser@citrix.com>
date Thu Feb 28 10:55:18 2008 +0000 (2008-02-28)
parents 831230e53067
children
line source
1 /*
2 * linux/arch/m68k/kernel/process.c
3 *
4 * Copyright (C) 1995 Hamish Macdonald
5 *
6 * 68060 fixes by Jesper Skov
7 */
9 /*
10 * This file handles the architecture-dependent parts of process handling..
11 */
13 #include <linux/errno.h>
14 #include <linux/module.h>
15 #include <linux/sched.h>
16 #include <linux/kernel.h>
17 #include <linux/mm.h>
18 #include <linux/smp.h>
19 #include <linux/smp_lock.h>
20 #include <linux/stddef.h>
21 #include <linux/unistd.h>
22 #include <linux/ptrace.h>
23 #include <linux/slab.h>
24 #include <linux/user.h>
25 #include <linux/a.out.h>
26 #include <linux/reboot.h>
27 #include <linux/init_task.h>
28 #include <linux/mqueue.h>
30 #include <asm/uaccess.h>
31 #include <asm/system.h>
32 #include <asm/traps.h>
33 #include <asm/machdep.h>
34 #include <asm/setup.h>
35 #include <asm/pgtable.h>
37 /*
38 * Initial task/thread structure. Make this a per-architecture thing,
39 * because different architectures tend to have different
40 * alignment requirements and potentially different initial
41 * setup.
42 */
43 static struct fs_struct init_fs = INIT_FS;
44 static struct files_struct init_files = INIT_FILES;
45 static struct signal_struct init_signals = INIT_SIGNALS(init_signals);
46 static struct sighand_struct init_sighand = INIT_SIGHAND(init_sighand);
47 struct mm_struct init_mm = INIT_MM(init_mm);
49 EXPORT_SYMBOL(init_mm);
51 union thread_union init_thread_union
52 __attribute__((section(".data.init_task"), aligned(THREAD_SIZE)))
53 = { INIT_THREAD_INFO(init_task) };
55 /* initial task structure */
56 struct task_struct init_task = INIT_TASK(init_task);
58 EXPORT_SYMBOL(init_task);
60 asmlinkage void ret_from_fork(void);
63 /*
64 * Return saved PC from a blocked thread
65 */
66 unsigned long thread_saved_pc(struct task_struct *tsk)
67 {
68 struct switch_stack *sw = (struct switch_stack *)tsk->thread.ksp;
69 /* Check whether the thread is blocked in resume() */
70 if (in_sched_functions(sw->retpc))
71 return ((unsigned long *)sw->a6)[1];
72 else
73 return sw->retpc;
74 }
76 /*
77 * The idle loop on an m68k..
78 */
79 static void default_idle(void)
80 {
81 if (!need_resched())
82 #if defined(MACH_ATARI_ONLY) && !defined(CONFIG_HADES)
83 /* block out HSYNC on the atari (falcon) */
84 __asm__("stop #0x2200" : : : "cc");
85 #else
86 __asm__("stop #0x2000" : : : "cc");
87 #endif
88 }
90 void (*idle)(void) = default_idle;
92 /*
93 * The idle thread. There's no useful work to be
94 * done, so just try to conserve power and have a
95 * low exit latency (ie sit in a loop waiting for
96 * somebody to say that they'd like to reschedule)
97 */
98 void cpu_idle(void)
99 {
100 /* endless idle loop with no priority at all */
101 while (1) {
102 while (!need_resched())
103 idle();
104 preempt_enable_no_resched();
105 schedule();
106 preempt_disable();
107 }
108 }
110 void machine_restart(char * __unused)
111 {
112 if (mach_reset)
113 mach_reset();
114 for (;;);
115 }
117 void machine_halt(void)
118 {
119 if (mach_halt)
120 mach_halt();
121 for (;;);
122 }
124 void machine_power_off(void)
125 {
126 if (mach_power_off)
127 mach_power_off();
128 for (;;);
129 }
131 void (*pm_power_off)(void) = machine_power_off;
132 EXPORT_SYMBOL(pm_power_off);
134 void show_regs(struct pt_regs * regs)
135 {
136 printk("\n");
137 printk("Format %02x Vector: %04x PC: %08lx Status: %04x %s\n",
138 regs->format, regs->vector, regs->pc, regs->sr, print_tainted());
139 printk("ORIG_D0: %08lx D0: %08lx A2: %08lx A1: %08lx\n",
140 regs->orig_d0, regs->d0, regs->a2, regs->a1);
141 printk("A0: %08lx D5: %08lx D4: %08lx\n",
142 regs->a0, regs->d5, regs->d4);
143 printk("D3: %08lx D2: %08lx D1: %08lx\n",
144 regs->d3, regs->d2, regs->d1);
145 if (!(regs->sr & PS_S))
146 printk("USP: %08lx\n", rdusp());
147 }
149 /*
150 * Create a kernel thread
151 */
152 int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
153 {
154 int pid;
155 mm_segment_t fs;
157 fs = get_fs();
158 set_fs (KERNEL_DS);
160 {
161 register long retval __asm__ ("d0");
162 register long clone_arg __asm__ ("d1") = flags | CLONE_VM | CLONE_UNTRACED;
164 retval = __NR_clone;
165 __asm__ __volatile__
166 ("clrl %%d2\n\t"
167 "trap #0\n\t" /* Linux/m68k system call */
168 "tstl %0\n\t" /* child or parent */
169 "jne 1f\n\t" /* parent - jump */
170 "lea %%sp@(%c7),%6\n\t" /* reload current */
171 "movel %6@,%6\n\t"
172 "movel %3,%%sp@-\n\t" /* push argument */
173 "jsr %4@\n\t" /* call fn */
174 "movel %0,%%d1\n\t" /* pass exit value */
175 "movel %2,%%d0\n\t" /* exit */
176 "trap #0\n"
177 "1:"
178 : "+d" (retval)
179 : "i" (__NR_clone), "i" (__NR_exit),
180 "r" (arg), "a" (fn), "d" (clone_arg), "r" (current),
181 "i" (-THREAD_SIZE)
182 : "d2");
184 pid = retval;
185 }
187 set_fs (fs);
188 return pid;
189 }
191 void flush_thread(void)
192 {
193 unsigned long zero = 0;
194 set_fs(USER_DS);
195 current->thread.fs = __USER_DS;
196 if (!FPU_IS_EMU)
197 asm volatile (".chip 68k/68881\n\t"
198 "frestore %0@\n\t"
199 ".chip 68k" : : "a" (&zero));
200 }
202 /*
203 * "m68k_fork()".. By the time we get here, the
204 * non-volatile registers have also been saved on the
205 * stack. We do some ugly pointer stuff here.. (see
206 * also copy_thread)
207 */
209 asmlinkage int m68k_fork(struct pt_regs *regs)
210 {
211 return do_fork(SIGCHLD, rdusp(), regs, 0, NULL, NULL);
212 }
214 asmlinkage int m68k_vfork(struct pt_regs *regs)
215 {
216 return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, rdusp(), regs, 0,
217 NULL, NULL);
218 }
220 asmlinkage int m68k_clone(struct pt_regs *regs)
221 {
222 unsigned long clone_flags;
223 unsigned long newsp;
224 int *parent_tidptr, *child_tidptr;
226 /* syscall2 puts clone_flags in d1 and usp in d2 */
227 clone_flags = regs->d1;
228 newsp = regs->d2;
229 parent_tidptr = (int *)regs->d3;
230 child_tidptr = (int *)regs->d4;
231 if (!newsp)
232 newsp = rdusp();
233 return do_fork(clone_flags, newsp, regs, 0,
234 parent_tidptr, child_tidptr);
235 }
237 int copy_thread(int nr, unsigned long clone_flags, unsigned long usp,
238 unsigned long unused,
239 struct task_struct * p, struct pt_regs * regs)
240 {
241 struct pt_regs * childregs;
242 struct switch_stack * childstack, *stack;
243 unsigned long *retp;
245 childregs = (struct pt_regs *) (task_stack_page(p) + THREAD_SIZE) - 1;
247 *childregs = *regs;
248 childregs->d0 = 0;
250 retp = ((unsigned long *) regs);
251 stack = ((struct switch_stack *) retp) - 1;
253 childstack = ((struct switch_stack *) childregs) - 1;
254 *childstack = *stack;
255 childstack->retpc = (unsigned long)ret_from_fork;
257 p->thread.usp = usp;
258 p->thread.ksp = (unsigned long)childstack;
259 /*
260 * Must save the current SFC/DFC value, NOT the value when
261 * the parent was last descheduled - RGH 10-08-96
262 */
263 p->thread.fs = get_fs().seg;
265 if (!FPU_IS_EMU) {
266 /* Copy the current fpu state */
267 asm volatile ("fsave %0" : : "m" (p->thread.fpstate[0]) : "memory");
269 if (!CPU_IS_060 ? p->thread.fpstate[0] : p->thread.fpstate[2])
270 asm volatile ("fmovemx %/fp0-%/fp7,%0\n\t"
271 "fmoveml %/fpiar/%/fpcr/%/fpsr,%1"
272 : : "m" (p->thread.fp[0]), "m" (p->thread.fpcntl[0])
273 : "memory");
274 /* Restore the state in case the fpu was busy */
275 asm volatile ("frestore %0" : : "m" (p->thread.fpstate[0]));
276 }
278 return 0;
279 }
281 /* Fill in the fpu structure for a core dump. */
283 int dump_fpu (struct pt_regs *regs, struct user_m68kfp_struct *fpu)
284 {
285 char fpustate[216];
287 if (FPU_IS_EMU) {
288 int i;
290 memcpy(fpu->fpcntl, current->thread.fpcntl, 12);
291 memcpy(fpu->fpregs, current->thread.fp, 96);
292 /* Convert internal fpu reg representation
293 * into long double format
294 */
295 for (i = 0; i < 24; i += 3)
296 fpu->fpregs[i] = ((fpu->fpregs[i] & 0xffff0000) << 15) |
297 ((fpu->fpregs[i] & 0x0000ffff) << 16);
298 return 1;
299 }
301 /* First dump the fpu context to avoid protocol violation. */
302 asm volatile ("fsave %0" :: "m" (fpustate[0]) : "memory");
303 if (!CPU_IS_060 ? !fpustate[0] : !fpustate[2])
304 return 0;
306 asm volatile ("fmovem %/fpiar/%/fpcr/%/fpsr,%0"
307 :: "m" (fpu->fpcntl[0])
308 : "memory");
309 asm volatile ("fmovemx %/fp0-%/fp7,%0"
310 :: "m" (fpu->fpregs[0])
311 : "memory");
312 return 1;
313 }
315 /*
316 * fill in the user structure for a core dump..
317 */
318 void dump_thread(struct pt_regs * regs, struct user * dump)
319 {
320 struct switch_stack *sw;
322 /* changed the size calculations - should hopefully work better. lbt */
323 dump->magic = CMAGIC;
324 dump->start_code = 0;
325 dump->start_stack = rdusp() & ~(PAGE_SIZE - 1);
326 dump->u_tsize = ((unsigned long) current->mm->end_code) >> PAGE_SHIFT;
327 dump->u_dsize = ((unsigned long) (current->mm->brk +
328 (PAGE_SIZE-1))) >> PAGE_SHIFT;
329 dump->u_dsize -= dump->u_tsize;
330 dump->u_ssize = 0;
332 if (dump->start_stack < TASK_SIZE)
333 dump->u_ssize = ((unsigned long) (TASK_SIZE - dump->start_stack)) >> PAGE_SHIFT;
335 dump->u_ar0 = (struct user_regs_struct *)((int)&dump->regs - (int)dump);
336 sw = ((struct switch_stack *)regs) - 1;
337 dump->regs.d1 = regs->d1;
338 dump->regs.d2 = regs->d2;
339 dump->regs.d3 = regs->d3;
340 dump->regs.d4 = regs->d4;
341 dump->regs.d5 = regs->d5;
342 dump->regs.d6 = sw->d6;
343 dump->regs.d7 = sw->d7;
344 dump->regs.a0 = regs->a0;
345 dump->regs.a1 = regs->a1;
346 dump->regs.a2 = regs->a2;
347 dump->regs.a3 = sw->a3;
348 dump->regs.a4 = sw->a4;
349 dump->regs.a5 = sw->a5;
350 dump->regs.a6 = sw->a6;
351 dump->regs.d0 = regs->d0;
352 dump->regs.orig_d0 = regs->orig_d0;
353 dump->regs.stkadj = regs->stkadj;
354 dump->regs.sr = regs->sr;
355 dump->regs.pc = regs->pc;
356 dump->regs.fmtvec = (regs->format << 12) | regs->vector;
357 /* dump floating point stuff */
358 dump->u_fpvalid = dump_fpu (regs, &dump->m68kfp);
359 }
361 /*
362 * sys_execve() executes a new program.
363 */
364 asmlinkage int sys_execve(char *name, char **argv, char **envp)
365 {
366 int error;
367 char * filename;
368 struct pt_regs *regs = (struct pt_regs *) &name;
370 lock_kernel();
371 filename = getname(name);
372 error = PTR_ERR(filename);
373 if (IS_ERR(filename))
374 goto out;
375 error = do_execve(filename, argv, envp, regs);
376 putname(filename);
377 out:
378 unlock_kernel();
379 return error;
380 }
382 unsigned long get_wchan(struct task_struct *p)
383 {
384 unsigned long fp, pc;
385 unsigned long stack_page;
386 int count = 0;
387 if (!p || p == current || p->state == TASK_RUNNING)
388 return 0;
390 stack_page = (unsigned long)task_stack_page(p);
391 fp = ((struct switch_stack *)p->thread.ksp)->a6;
392 do {
393 if (fp < stack_page+sizeof(struct thread_info) ||
394 fp >= 8184+stack_page)
395 return 0;
396 pc = ((unsigned long *)fp)[1];
397 if (!in_sched_functions(pc))
398 return pc;
399 fp = *(unsigned long *) fp;
400 } while (count++ < 16);
401 return 0;
402 }