2 * arch/sh/kernel/process_64.c
4 * This file handles the architecture-dependent parts of process handling..
6 * Copyright (C) 2000, 2001 Paolo Alberelli
7 * Copyright (C) 2003 - 2007 Paul Mundt
8 * Copyright (C) 2003, 2004 Richard Curnow
10 * Started from SH3/4 version:
11 * Copyright (C) 1999, 2000 Niibe Yutaka & Kaz Kojima
13 * In turn started from i386 version:
14 * Copyright (C) 1995 Linus Torvalds
16 * This file is subject to the terms and conditions of the GNU General Public
17 * License. See the file "COPYING" in the main directory of this archive
22 #include <linux/ptrace.h>
23 #include <linux/reboot.h>
24 #include <linux/slab.h>
25 #include <linux/init.h>
26 #include <linux/module.h>
28 #include <linux/sched/debug.h>
29 #include <linux/sched/task.h>
30 #include <asm/syscalls.h>
31 #include <linux/uaccess.h>
32 #include <asm/pgtable.h>
33 #include <asm/mmu_context.h>
35 #include <asm/switch_to.h>
37 struct task_struct *last_task_used_math = NULL;
38 struct pt_regs fake_swapper_regs = { 0, };
40 void show_regs(struct pt_regs *regs)
42 unsigned long long ah, al, bh, bl, ch, cl;
45 show_regs_print_info(KERN_DEFAULT);
47 ah = (regs->pc) >> 32;
48 al = (regs->pc) & 0xffffffff;
49 bh = (regs->regs[18]) >> 32;
50 bl = (regs->regs[18]) & 0xffffffff;
51 ch = (regs->regs[15]) >> 32;
52 cl = (regs->regs[15]) & 0xffffffff;
53 printk("PC : %08Lx%08Lx LINK: %08Lx%08Lx SP : %08Lx%08Lx\n",
54 ah, al, bh, bl, ch, cl);
56 ah = (regs->sr) >> 32;
57 al = (regs->sr) & 0xffffffff;
58 asm volatile ("getcon " __TEA ", %0" : "=r" (bh));
59 asm volatile ("getcon " __TEA ", %0" : "=r" (bl));
61 bl = (bl) & 0xffffffff;
62 asm volatile ("getcon " __KCR0 ", %0" : "=r" (ch));
63 asm volatile ("getcon " __KCR0 ", %0" : "=r" (cl));
65 cl = (cl) & 0xffffffff;
66 printk("SR : %08Lx%08Lx TEA : %08Lx%08Lx KCR0: %08Lx%08Lx\n",
67 ah, al, bh, bl, ch, cl);
69 ah = (regs->regs[0]) >> 32;
70 al = (regs->regs[0]) & 0xffffffff;
71 bh = (regs->regs[1]) >> 32;
72 bl = (regs->regs[1]) & 0xffffffff;
73 ch = (regs->regs[2]) >> 32;
74 cl = (regs->regs[2]) & 0xffffffff;
75 printk("R0 : %08Lx%08Lx R1 : %08Lx%08Lx R2 : %08Lx%08Lx\n",
76 ah, al, bh, bl, ch, cl);
78 ah = (regs->regs[3]) >> 32;
79 al = (regs->regs[3]) & 0xffffffff;
80 bh = (regs->regs[4]) >> 32;
81 bl = (regs->regs[4]) & 0xffffffff;
82 ch = (regs->regs[5]) >> 32;
83 cl = (regs->regs[5]) & 0xffffffff;
84 printk("R3 : %08Lx%08Lx R4 : %08Lx%08Lx R5 : %08Lx%08Lx\n",
85 ah, al, bh, bl, ch, cl);
87 ah = (regs->regs[6]) >> 32;
88 al = (regs->regs[6]) & 0xffffffff;
89 bh = (regs->regs[7]) >> 32;
90 bl = (regs->regs[7]) & 0xffffffff;
91 ch = (regs->regs[8]) >> 32;
92 cl = (regs->regs[8]) & 0xffffffff;
93 printk("R6 : %08Lx%08Lx R7 : %08Lx%08Lx R8 : %08Lx%08Lx\n",
94 ah, al, bh, bl, ch, cl);
96 ah = (regs->regs[9]) >> 32;
97 al = (regs->regs[9]) & 0xffffffff;
98 bh = (regs->regs[10]) >> 32;
99 bl = (regs->regs[10]) & 0xffffffff;
100 ch = (regs->regs[11]) >> 32;
101 cl = (regs->regs[11]) & 0xffffffff;
102 printk("R9 : %08Lx%08Lx R10 : %08Lx%08Lx R11 : %08Lx%08Lx\n",
103 ah, al, bh, bl, ch, cl);
105 ah = (regs->regs[12]) >> 32;
106 al = (regs->regs[12]) & 0xffffffff;
107 bh = (regs->regs[13]) >> 32;
108 bl = (regs->regs[13]) & 0xffffffff;
109 ch = (regs->regs[14]) >> 32;
110 cl = (regs->regs[14]) & 0xffffffff;
111 printk("R12 : %08Lx%08Lx R13 : %08Lx%08Lx R14 : %08Lx%08Lx\n",
112 ah, al, bh, bl, ch, cl);
114 ah = (regs->regs[16]) >> 32;
115 al = (regs->regs[16]) & 0xffffffff;
116 bh = (regs->regs[17]) >> 32;
117 bl = (regs->regs[17]) & 0xffffffff;
118 ch = (regs->regs[19]) >> 32;
119 cl = (regs->regs[19]) & 0xffffffff;
120 printk("R16 : %08Lx%08Lx R17 : %08Lx%08Lx R19 : %08Lx%08Lx\n",
121 ah, al, bh, bl, ch, cl);
123 ah = (regs->regs[20]) >> 32;
124 al = (regs->regs[20]) & 0xffffffff;
125 bh = (regs->regs[21]) >> 32;
126 bl = (regs->regs[21]) & 0xffffffff;
127 ch = (regs->regs[22]) >> 32;
128 cl = (regs->regs[22]) & 0xffffffff;
129 printk("R20 : %08Lx%08Lx R21 : %08Lx%08Lx R22 : %08Lx%08Lx\n",
130 ah, al, bh, bl, ch, cl);
132 ah = (regs->regs[23]) >> 32;
133 al = (regs->regs[23]) & 0xffffffff;
134 bh = (regs->regs[24]) >> 32;
135 bl = (regs->regs[24]) & 0xffffffff;
136 ch = (regs->regs[25]) >> 32;
137 cl = (regs->regs[25]) & 0xffffffff;
138 printk("R23 : %08Lx%08Lx R24 : %08Lx%08Lx R25 : %08Lx%08Lx\n",
139 ah, al, bh, bl, ch, cl);
141 ah = (regs->regs[26]) >> 32;
142 al = (regs->regs[26]) & 0xffffffff;
143 bh = (regs->regs[27]) >> 32;
144 bl = (regs->regs[27]) & 0xffffffff;
145 ch = (regs->regs[28]) >> 32;
146 cl = (regs->regs[28]) & 0xffffffff;
147 printk("R26 : %08Lx%08Lx R27 : %08Lx%08Lx R28 : %08Lx%08Lx\n",
148 ah, al, bh, bl, ch, cl);
150 ah = (regs->regs[29]) >> 32;
151 al = (regs->regs[29]) & 0xffffffff;
152 bh = (regs->regs[30]) >> 32;
153 bl = (regs->regs[30]) & 0xffffffff;
154 ch = (regs->regs[31]) >> 32;
155 cl = (regs->regs[31]) & 0xffffffff;
156 printk("R29 : %08Lx%08Lx R30 : %08Lx%08Lx R31 : %08Lx%08Lx\n",
157 ah, al, bh, bl, ch, cl);
159 ah = (regs->regs[32]) >> 32;
160 al = (regs->regs[32]) & 0xffffffff;
161 bh = (regs->regs[33]) >> 32;
162 bl = (regs->regs[33]) & 0xffffffff;
163 ch = (regs->regs[34]) >> 32;
164 cl = (regs->regs[34]) & 0xffffffff;
165 printk("R32 : %08Lx%08Lx R33 : %08Lx%08Lx R34 : %08Lx%08Lx\n",
166 ah, al, bh, bl, ch, cl);
168 ah = (regs->regs[35]) >> 32;
169 al = (regs->regs[35]) & 0xffffffff;
170 bh = (regs->regs[36]) >> 32;
171 bl = (regs->regs[36]) & 0xffffffff;
172 ch = (regs->regs[37]) >> 32;
173 cl = (regs->regs[37]) & 0xffffffff;
174 printk("R35 : %08Lx%08Lx R36 : %08Lx%08Lx R37 : %08Lx%08Lx\n",
175 ah, al, bh, bl, ch, cl);
177 ah = (regs->regs[38]) >> 32;
178 al = (regs->regs[38]) & 0xffffffff;
179 bh = (regs->regs[39]) >> 32;
180 bl = (regs->regs[39]) & 0xffffffff;
181 ch = (regs->regs[40]) >> 32;
182 cl = (regs->regs[40]) & 0xffffffff;
183 printk("R38 : %08Lx%08Lx R39 : %08Lx%08Lx R40 : %08Lx%08Lx\n",
184 ah, al, bh, bl, ch, cl);
186 ah = (regs->regs[41]) >> 32;
187 al = (regs->regs[41]) & 0xffffffff;
188 bh = (regs->regs[42]) >> 32;
189 bl = (regs->regs[42]) & 0xffffffff;
190 ch = (regs->regs[43]) >> 32;
191 cl = (regs->regs[43]) & 0xffffffff;
192 printk("R41 : %08Lx%08Lx R42 : %08Lx%08Lx R43 : %08Lx%08Lx\n",
193 ah, al, bh, bl, ch, cl);
195 ah = (regs->regs[44]) >> 32;
196 al = (regs->regs[44]) & 0xffffffff;
197 bh = (regs->regs[45]) >> 32;
198 bl = (regs->regs[45]) & 0xffffffff;
199 ch = (regs->regs[46]) >> 32;
200 cl = (regs->regs[46]) & 0xffffffff;
201 printk("R44 : %08Lx%08Lx R45 : %08Lx%08Lx R46 : %08Lx%08Lx\n",
202 ah, al, bh, bl, ch, cl);
204 ah = (regs->regs[47]) >> 32;
205 al = (regs->regs[47]) & 0xffffffff;
206 bh = (regs->regs[48]) >> 32;
207 bl = (regs->regs[48]) & 0xffffffff;
208 ch = (regs->regs[49]) >> 32;
209 cl = (regs->regs[49]) & 0xffffffff;
210 printk("R47 : %08Lx%08Lx R48 : %08Lx%08Lx R49 : %08Lx%08Lx\n",
211 ah, al, bh, bl, ch, cl);
213 ah = (regs->regs[50]) >> 32;
214 al = (regs->regs[50]) & 0xffffffff;
215 bh = (regs->regs[51]) >> 32;
216 bl = (regs->regs[51]) & 0xffffffff;
217 ch = (regs->regs[52]) >> 32;
218 cl = (regs->regs[52]) & 0xffffffff;
219 printk("R50 : %08Lx%08Lx R51 : %08Lx%08Lx R52 : %08Lx%08Lx\n",
220 ah, al, bh, bl, ch, cl);
222 ah = (regs->regs[53]) >> 32;
223 al = (regs->regs[53]) & 0xffffffff;
224 bh = (regs->regs[54]) >> 32;
225 bl = (regs->regs[54]) & 0xffffffff;
226 ch = (regs->regs[55]) >> 32;
227 cl = (regs->regs[55]) & 0xffffffff;
228 printk("R53 : %08Lx%08Lx R54 : %08Lx%08Lx R55 : %08Lx%08Lx\n",
229 ah, al, bh, bl, ch, cl);
231 ah = (regs->regs[56]) >> 32;
232 al = (regs->regs[56]) & 0xffffffff;
233 bh = (regs->regs[57]) >> 32;
234 bl = (regs->regs[57]) & 0xffffffff;
235 ch = (regs->regs[58]) >> 32;
236 cl = (regs->regs[58]) & 0xffffffff;
237 printk("R56 : %08Lx%08Lx R57 : %08Lx%08Lx R58 : %08Lx%08Lx\n",
238 ah, al, bh, bl, ch, cl);
240 ah = (regs->regs[59]) >> 32;
241 al = (regs->regs[59]) & 0xffffffff;
242 bh = (regs->regs[60]) >> 32;
243 bl = (regs->regs[60]) & 0xffffffff;
244 ch = (regs->regs[61]) >> 32;
245 cl = (regs->regs[61]) & 0xffffffff;
246 printk("R59 : %08Lx%08Lx R60 : %08Lx%08Lx R61 : %08Lx%08Lx\n",
247 ah, al, bh, bl, ch, cl);
249 ah = (regs->regs[62]) >> 32;
250 al = (regs->regs[62]) & 0xffffffff;
251 bh = (regs->tregs[0]) >> 32;
252 bl = (regs->tregs[0]) & 0xffffffff;
253 ch = (regs->tregs[1]) >> 32;
254 cl = (regs->tregs[1]) & 0xffffffff;
255 printk("R62 : %08Lx%08Lx T0 : %08Lx%08Lx T1 : %08Lx%08Lx\n",
256 ah, al, bh, bl, ch, cl);
258 ah = (regs->tregs[2]) >> 32;
259 al = (regs->tregs[2]) & 0xffffffff;
260 bh = (regs->tregs[3]) >> 32;
261 bl = (regs->tregs[3]) & 0xffffffff;
262 ch = (regs->tregs[4]) >> 32;
263 cl = (regs->tregs[4]) & 0xffffffff;
264 printk("T2 : %08Lx%08Lx T3 : %08Lx%08Lx T4 : %08Lx%08Lx\n",
265 ah, al, bh, bl, ch, cl);
267 ah = (regs->tregs[5]) >> 32;
268 al = (regs->tregs[5]) & 0xffffffff;
269 bh = (regs->tregs[6]) >> 32;
270 bl = (regs->tregs[6]) & 0xffffffff;
271 ch = (regs->tregs[7]) >> 32;
272 cl = (regs->tregs[7]) & 0xffffffff;
273 printk("T5 : %08Lx%08Lx T6 : %08Lx%08Lx T7 : %08Lx%08Lx\n",
274 ah, al, bh, bl, ch, cl);
277 * If we're in kernel mode, dump the stack too..
279 if (!user_mode(regs)) {
280 void show_stack(struct task_struct *tsk, unsigned long *sp);
281 unsigned long sp = regs->regs[15] & 0xffffffff;
282 struct task_struct *tsk = get_current();
284 tsk->thread.kregs = regs;
286 show_stack(tsk, (unsigned long *)sp);
291 * Free current thread data structures etc..
293 void exit_thread(struct task_struct *tsk)
296 * See arch/sparc/kernel/process.c for the precedent for doing
299 * The SH-5 FPU save/restore approach relies on
300 * last_task_used_math pointing to a live task_struct. When
301 * another task tries to use the FPU for the 1st time, the FPUDIS
302 * trap handling (see arch/sh/kernel/cpu/sh5/fpu.c) will save the
303 * existing FPU state to the FP regs field within
304 * last_task_used_math before re-loading the new task's FPU state
305 * (or initialising it if the FPU has been used before). So if
306 * last_task_used_math is stale, and its page has already been
307 * re-allocated for another use, the consequences are rather
308 * grim. Unless we null it here, there is no other path through
309 * which it would get safely nulled.
312 if (last_task_used_math == tsk)
313 last_task_used_math = NULL;
317 void flush_thread(void)
320 /* Called by fs/exec.c (setup_new_exec) to remove traces of a
321 * previously running executable. */
323 if (last_task_used_math == current) {
324 last_task_used_math = NULL;
326 /* Force FPU state to be reinitialised after exec */
330 /* if we are a kernel thread, about to change to user thread,
333 if(current->thread.kregs==&fake_swapper_regs) {
334 current->thread.kregs =
335 ((struct pt_regs *)(THREAD_SIZE + (unsigned long) current) - 1);
336 current->thread.uregs = current->thread.kregs;
340 void release_thread(struct task_struct *dead_task)
345 /* Fill in the fpu structure for a core dump.. */
346 int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpu)
350 struct task_struct *tsk = current;
352 fpvalid = !!tsk_used_math(tsk);
354 if (current == last_task_used_math) {
358 last_task_used_math = 0;
362 memcpy(fpu, &tsk->thread.xstate->hardfpu, sizeof(*fpu));
367 return 0; /* Task didn't use the fpu at all. */
370 EXPORT_SYMBOL(dump_fpu);
372 asmlinkage void ret_from_fork(void);
373 asmlinkage void ret_from_kernel_thread(void);
375 int copy_thread(unsigned long clone_flags, unsigned long usp,
376 unsigned long arg, struct task_struct *p)
378 struct pt_regs *childregs;
381 /* can't happen for a kernel thread */
382 if (last_task_used_math == current) {
386 last_task_used_math = NULL;
387 current_pt_regs()->sr |= SR_FD;
390 /* Copy from sh version */
391 childregs = (struct pt_regs *)(THREAD_SIZE + task_stack_page(p)) - 1;
392 p->thread.sp = (unsigned long) childregs;
394 if (unlikely(p->flags & PF_KTHREAD)) {
395 memset(childregs, 0, sizeof(struct pt_regs));
396 childregs->regs[2] = (unsigned long)arg;
397 childregs->regs[3] = (unsigned long)usp;
398 childregs->sr = (1 << 30); /* not user_mode */
399 childregs->sr |= SR_FD; /* Invalidate FPU flag */
400 p->thread.pc = (unsigned long) ret_from_kernel_thread;
403 *childregs = *current_pt_regs();
406 * Sign extend the edited stack.
407 * Note that thread.pc and thread.pc will stay
408 * 32-bit wide and context switch must take care
409 * of NEFF sign extension.
412 childregs->regs[15] = neff_sign_extend(usp);
413 p->thread.uregs = childregs;
415 childregs->regs[9] = 0; /* Set return value for child */
416 childregs->sr |= SR_FD; /* Invalidate FPU flag */
418 p->thread.pc = (unsigned long) ret_from_fork;
423 #ifdef CONFIG_FRAME_POINTER
424 static int in_sh64_switch_to(unsigned long pc)
426 extern char __sh64_switch_to_end;
427 /* For a sleeping task, the PC is somewhere in the middle of the function,
428 so we don't have to worry about masking the LSB off */
429 return (pc >= (unsigned long) sh64_switch_to) &&
430 (pc < (unsigned long) &__sh64_switch_to_end);
434 unsigned long get_wchan(struct task_struct *p)
438 if (!p || p == current || p->state == TASK_RUNNING)
442 * The same comment as on the Alpha applies here, too ...
444 pc = thread_saved_pc(p);
446 #ifdef CONFIG_FRAME_POINTER
447 if (in_sh64_switch_to(pc)) {
448 unsigned long schedule_fp;
449 unsigned long sh64_switch_to_fp;
450 unsigned long schedule_caller_pc;
452 sh64_switch_to_fp = (long) p->thread.sp;
453 /* r14 is saved at offset 4 in the sh64_switch_to frame */
454 schedule_fp = *(unsigned long *) (long)(sh64_switch_to_fp + 4);
456 /* and the caller of 'schedule' is (currently!) saved at offset 24
457 in the frame of schedule (from disasm) */
458 schedule_caller_pc = *(unsigned long *) (long)(schedule_fp + 24);
459 return schedule_caller_pc;