1 /* arch/sparc64/kernel/process.c
3 * Copyright (C) 1995, 1996, 2008 David S. Miller (davem@davemloft.net)
4 * Copyright (C) 1996 Eddie C. Dost (ecd@skynet.be)
5 * Copyright (C) 1997, 1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
9 * This file handles the architecture-dependent parts of process handling..
14 #include <linux/errno.h>
15 #include <linux/export.h>
16 #include <linux/sched.h>
17 #include <linux/kernel.h>
20 #include <linux/smp.h>
21 #include <linux/stddef.h>
22 #include <linux/ptrace.h>
23 #include <linux/slab.h>
24 #include <linux/user.h>
25 #include <linux/delay.h>
26 #include <linux/compat.h>
27 #include <linux/tick.h>
28 #include <linux/init.h>
29 #include <linux/cpu.h>
30 #include <linux/elfcore.h>
31 #include <linux/sysrq.h>
32 #include <linux/nmi.h>
34 #include <asm/uaccess.h>
35 #include <asm/system.h>
37 #include <asm/pgalloc.h>
38 #include <asm/pgtable.h>
39 #include <asm/processor.h>
40 #include <asm/pstate.h>
42 #include <asm/fpumacro.h>
44 #include <asm/cpudata.h>
45 #include <asm/mmu_context.h>
46 #include <asm/unistd.h>
47 #include <asm/hypervisor.h>
48 #include <asm/syscalls.h>
49 #include <asm/irq_regs.h>
54 static void sparc64_yield(int cpu)
56 if (tlb_type != hypervisor) {
61 clear_thread_flag(TIF_POLLING_NRFLAG);
62 smp_mb__after_clear_bit();
64 while (!need_resched() && !cpu_is_offline(cpu)) {
67 /* Disable interrupts. */
69 "rdpr %%pstate, %0\n\t"
71 "wrpr %0, %%g0, %%pstate"
75 if (!need_resched() && !cpu_is_offline(cpu))
78 /* Re-enable interrupts. */
80 "rdpr %%pstate, %0\n\t"
82 "wrpr %0, %%g0, %%pstate"
87 set_thread_flag(TIF_POLLING_NRFLAG);
90 /* The idle loop on sparc64. */
93 int cpu = smp_processor_id();
95 set_thread_flag(TIF_POLLING_NRFLAG);
98 tick_nohz_idle_enter_norcu();
100 while (!need_resched() && !cpu_is_offline(cpu))
103 tick_nohz_idle_exit_norcu();
105 preempt_enable_no_resched();
107 #ifdef CONFIG_HOTPLUG_CPU
108 if (cpu_is_offline(cpu))
118 static void show_regwindow32(struct pt_regs *regs)
120 struct reg_window32 __user *rw;
121 struct reg_window32 r_w;
124 __asm__ __volatile__ ("flushw");
125 rw = compat_ptr((unsigned)regs->u_regs[14]);
128 if (copy_from_user (&r_w, rw, sizeof(r_w))) {
134 printk("l0: %08x l1: %08x l2: %08x l3: %08x "
135 "l4: %08x l5: %08x l6: %08x l7: %08x\n",
136 r_w.locals[0], r_w.locals[1], r_w.locals[2], r_w.locals[3],
137 r_w.locals[4], r_w.locals[5], r_w.locals[6], r_w.locals[7]);
138 printk("i0: %08x i1: %08x i2: %08x i3: %08x "
139 "i4: %08x i5: %08x i6: %08x i7: %08x\n",
140 r_w.ins[0], r_w.ins[1], r_w.ins[2], r_w.ins[3],
141 r_w.ins[4], r_w.ins[5], r_w.ins[6], r_w.ins[7]);
144 #define show_regwindow32(regs) do { } while (0)
147 static void show_regwindow(struct pt_regs *regs)
149 struct reg_window __user *rw;
150 struct reg_window *rwk;
151 struct reg_window r_w;
154 if ((regs->tstate & TSTATE_PRIV) || !(test_thread_flag(TIF_32BIT))) {
155 __asm__ __volatile__ ("flushw");
156 rw = (struct reg_window __user *)
157 (regs->u_regs[14] + STACK_BIAS);
158 rwk = (struct reg_window *)
159 (regs->u_regs[14] + STACK_BIAS);
160 if (!(regs->tstate & TSTATE_PRIV)) {
163 if (copy_from_user (&r_w, rw, sizeof(r_w))) {
171 show_regwindow32(regs);
174 printk("l0: %016lx l1: %016lx l2: %016lx l3: %016lx\n",
175 rwk->locals[0], rwk->locals[1], rwk->locals[2], rwk->locals[3]);
176 printk("l4: %016lx l5: %016lx l6: %016lx l7: %016lx\n",
177 rwk->locals[4], rwk->locals[5], rwk->locals[6], rwk->locals[7]);
178 printk("i0: %016lx i1: %016lx i2: %016lx i3: %016lx\n",
179 rwk->ins[0], rwk->ins[1], rwk->ins[2], rwk->ins[3]);
180 printk("i4: %016lx i5: %016lx i6: %016lx i7: %016lx\n",
181 rwk->ins[4], rwk->ins[5], rwk->ins[6], rwk->ins[7]);
182 if (regs->tstate & TSTATE_PRIV)
183 printk("I7: <%pS>\n", (void *) rwk->ins[7]);
186 void show_regs(struct pt_regs *regs)
188 printk("TSTATE: %016lx TPC: %016lx TNPC: %016lx Y: %08x %s\n", regs->tstate,
189 regs->tpc, regs->tnpc, regs->y, print_tainted());
190 printk("TPC: <%pS>\n", (void *) regs->tpc);
191 printk("g0: %016lx g1: %016lx g2: %016lx g3: %016lx\n",
192 regs->u_regs[0], regs->u_regs[1], regs->u_regs[2],
194 printk("g4: %016lx g5: %016lx g6: %016lx g7: %016lx\n",
195 regs->u_regs[4], regs->u_regs[5], regs->u_regs[6],
197 printk("o0: %016lx o1: %016lx o2: %016lx o3: %016lx\n",
198 regs->u_regs[8], regs->u_regs[9], regs->u_regs[10],
200 printk("o4: %016lx o5: %016lx sp: %016lx ret_pc: %016lx\n",
201 regs->u_regs[12], regs->u_regs[13], regs->u_regs[14],
203 printk("RPC: <%pS>\n", (void *) regs->u_regs[15]);
204 show_regwindow(regs);
205 show_stack(current, (unsigned long *) regs->u_regs[UREG_FP]);
208 struct global_reg_snapshot global_reg_snapshot[NR_CPUS];
209 static DEFINE_SPINLOCK(global_reg_snapshot_lock);
211 static void __global_reg_self(struct thread_info *tp, struct pt_regs *regs,
216 global_reg_snapshot[this_cpu].tstate = regs->tstate;
217 global_reg_snapshot[this_cpu].tpc = regs->tpc;
218 global_reg_snapshot[this_cpu].tnpc = regs->tnpc;
219 global_reg_snapshot[this_cpu].o7 = regs->u_regs[UREG_I7];
221 if (regs->tstate & TSTATE_PRIV) {
222 struct reg_window *rw;
224 rw = (struct reg_window *)
225 (regs->u_regs[UREG_FP] + STACK_BIAS);
226 if (kstack_valid(tp, (unsigned long) rw)) {
227 global_reg_snapshot[this_cpu].i7 = rw->ins[7];
228 rw = (struct reg_window *)
229 (rw->ins[6] + STACK_BIAS);
230 if (kstack_valid(tp, (unsigned long) rw))
231 global_reg_snapshot[this_cpu].rpc = rw->ins[7];
234 global_reg_snapshot[this_cpu].i7 = 0;
235 global_reg_snapshot[this_cpu].rpc = 0;
237 global_reg_snapshot[this_cpu].thread = tp;
240 /* In order to avoid hangs we do not try to synchronize with the
241 * global register dump client cpus. The last store they make is to
242 * the thread pointer, so do a short poll waiting for that to become
245 static void __global_reg_poll(struct global_reg_snapshot *gp)
249 while (!gp->thread && ++limit < 100) {
255 void arch_trigger_all_cpu_backtrace(void)
257 struct thread_info *tp = current_thread_info();
258 struct pt_regs *regs = get_irq_regs();
265 spin_lock_irqsave(&global_reg_snapshot_lock, flags);
267 memset(global_reg_snapshot, 0, sizeof(global_reg_snapshot));
269 this_cpu = raw_smp_processor_id();
271 __global_reg_self(tp, regs, this_cpu);
273 smp_fetch_global_regs();
275 for_each_online_cpu(cpu) {
276 struct global_reg_snapshot *gp = &global_reg_snapshot[cpu];
278 __global_reg_poll(gp);
281 printk("%c CPU[%3d]: TSTATE[%016lx] TPC[%016lx] TNPC[%016lx] TASK[%s:%d]\n",
282 (cpu == this_cpu ? '*' : ' '), cpu,
283 gp->tstate, gp->tpc, gp->tnpc,
284 ((tp && tp->task) ? tp->task->comm : "NULL"),
285 ((tp && tp->task) ? tp->task->pid : -1));
287 if (gp->tstate & TSTATE_PRIV) {
288 printk(" TPC[%pS] O7[%pS] I7[%pS] RPC[%pS]\n",
294 printk(" TPC[%lx] O7[%lx] I7[%lx] RPC[%lx]\n",
295 gp->tpc, gp->o7, gp->i7, gp->rpc);
299 memset(global_reg_snapshot, 0, sizeof(global_reg_snapshot));
301 spin_unlock_irqrestore(&global_reg_snapshot_lock, flags);
304 #ifdef CONFIG_MAGIC_SYSRQ
306 static void sysrq_handle_globreg(int key)
308 arch_trigger_all_cpu_backtrace();
311 static struct sysrq_key_op sparc_globalreg_op = {
312 .handler = sysrq_handle_globreg,
313 .help_msg = "Globalregs",
314 .action_msg = "Show Global CPU Regs",
317 static int __init sparc_globreg_init(void)
319 return register_sysrq_key('y', &sparc_globalreg_op);
322 core_initcall(sparc_globreg_init);
326 unsigned long thread_saved_pc(struct task_struct *tsk)
328 struct thread_info *ti = task_thread_info(tsk);
329 unsigned long ret = 0xdeadbeefUL;
333 sp = (unsigned long *)(ti->ksp + STACK_BIAS);
334 if (((unsigned long)sp & (sizeof(long) - 1)) == 0UL &&
337 fp = (unsigned long *)(sp[14] + STACK_BIAS);
338 if (((unsigned long)fp & (sizeof(long) - 1)) == 0UL)
345 /* Free current thread data structures etc.. */
346 void exit_thread(void)
348 struct thread_info *t = current_thread_info();
351 if (t->utraps[0] < 2)
358 void flush_thread(void)
360 struct thread_info *t = current_thread_info();
361 struct mm_struct *mm;
365 tsb_context_switch(mm);
367 set_thread_wsaved(0);
369 /* Clear FPU register state. */
373 /* It's a bit more tricky when 64-bit tasks are involved... */
374 static unsigned long clone_stackframe(unsigned long csp, unsigned long psp)
376 unsigned long fp, distance, rval;
378 if (!(test_thread_flag(TIF_32BIT))) {
381 __get_user(fp, &(((struct reg_window __user *)psp)->ins[6]));
384 __get_user(fp, &(((struct reg_window32 __user *)psp)->ins[6]));
386 /* Now align the stack as this is mandatory in the Sparc ABI
387 * due to how register windows work. This hides the
388 * restriction from thread libraries etc.
393 rval = (csp - distance);
394 if (copy_in_user((void __user *) rval, (void __user *) psp, distance))
396 else if (test_thread_flag(TIF_32BIT)) {
397 if (put_user(((u32)csp),
398 &(((struct reg_window32 __user *)rval)->ins[6])))
401 if (put_user(((u64)csp - STACK_BIAS),
402 &(((struct reg_window __user *)rval)->ins[6])))
405 rval = rval - STACK_BIAS;
411 /* Standard stuff. */
412 static inline void shift_window_buffer(int first_win, int last_win,
413 struct thread_info *t)
417 for (i = first_win; i < last_win; i++) {
418 t->rwbuf_stkptrs[i] = t->rwbuf_stkptrs[i+1];
419 memcpy(&t->reg_window[i], &t->reg_window[i+1],
420 sizeof(struct reg_window));
424 void synchronize_user_stack(void)
426 struct thread_info *t = current_thread_info();
427 unsigned long window;
429 flush_user_windows();
430 if ((window = get_thread_wsaved()) != 0) {
431 int winsize = sizeof(struct reg_window);
434 if (test_thread_flag(TIF_32BIT))
435 winsize = sizeof(struct reg_window32);
441 unsigned long sp = (t->rwbuf_stkptrs[window] + bias);
442 struct reg_window *rwin = &t->reg_window[window];
444 if (!copy_to_user((char __user *)sp, rwin, winsize)) {
445 shift_window_buffer(window, get_thread_wsaved() - 1, t);
446 set_thread_wsaved(get_thread_wsaved() - 1);
452 static void stack_unaligned(unsigned long sp)
456 info.si_signo = SIGBUS;
458 info.si_code = BUS_ADRALN;
459 info.si_addr = (void __user *) sp;
461 force_sig_info(SIGBUS, &info, current);
464 void fault_in_user_windows(void)
466 struct thread_info *t = current_thread_info();
467 unsigned long window;
468 int winsize = sizeof(struct reg_window);
471 if (test_thread_flag(TIF_32BIT))
472 winsize = sizeof(struct reg_window32);
476 flush_user_windows();
477 window = get_thread_wsaved();
479 if (likely(window != 0)) {
482 unsigned long sp = (t->rwbuf_stkptrs[window] + bias);
483 struct reg_window *rwin = &t->reg_window[window];
485 if (unlikely(sp & 0x7UL))
488 if (unlikely(copy_to_user((char __user *)sp,
493 set_thread_wsaved(0);
497 set_thread_wsaved(window + 1);
501 asmlinkage long sparc_do_fork(unsigned long clone_flags,
502 unsigned long stack_start,
503 struct pt_regs *regs,
504 unsigned long stack_size)
506 int __user *parent_tid_ptr, *child_tid_ptr;
507 unsigned long orig_i1 = regs->u_regs[UREG_I1];
511 if (test_thread_flag(TIF_32BIT)) {
512 parent_tid_ptr = compat_ptr(regs->u_regs[UREG_I2]);
513 child_tid_ptr = compat_ptr(regs->u_regs[UREG_I4]);
517 parent_tid_ptr = (int __user *) regs->u_regs[UREG_I2];
518 child_tid_ptr = (int __user *) regs->u_regs[UREG_I4];
521 ret = do_fork(clone_flags, stack_start,
523 parent_tid_ptr, child_tid_ptr);
525 /* If we get an error and potentially restart the system
526 * call, we're screwed because copy_thread() clobbered
527 * the parent's %o1. So detect that case and restore it
530 if ((unsigned long)ret >= -ERESTART_RESTARTBLOCK)
531 regs->u_regs[UREG_I1] = orig_i1;
536 /* Copy a Sparc thread. The fork() return value conventions
537 * under SunOS are nothing short of bletcherous:
538 * Parent --> %o0 == childs pid, %o1 == 0
539 * Child --> %o0 == parents pid, %o1 == 1
541 int copy_thread(unsigned long clone_flags, unsigned long sp,
542 unsigned long unused,
543 struct task_struct *p, struct pt_regs *regs)
545 struct thread_info *t = task_thread_info(p);
546 struct sparc_stackf *parent_sf;
547 unsigned long child_stack_sz;
548 char *child_trap_frame;
551 kernel_thread = (regs->tstate & TSTATE_PRIV) ? 1 : 0;
552 parent_sf = ((struct sparc_stackf *) regs) - 1;
554 /* Calculate offset to stack_frame & pt_regs */
555 child_stack_sz = ((STACKFRAME_SZ + TRACEREG_SZ) +
556 (kernel_thread ? STACKFRAME_SZ : 0));
557 child_trap_frame = (task_stack_page(p) +
558 (THREAD_SIZE - child_stack_sz));
559 memcpy(child_trap_frame, parent_sf, child_stack_sz);
561 t->flags = (t->flags & ~((0xffUL << TI_FLAG_CWP_SHIFT) |
562 (0xffUL << TI_FLAG_CURRENT_DS_SHIFT))) |
563 (((regs->tstate + 1) & TSTATE_CWP) << TI_FLAG_CWP_SHIFT);
565 t->ksp = ((unsigned long) child_trap_frame) - STACK_BIAS;
566 t->kregs = (struct pt_regs *) (child_trap_frame +
567 sizeof(struct sparc_stackf));
571 struct sparc_stackf *child_sf = (struct sparc_stackf *)
572 (child_trap_frame + (STACKFRAME_SZ + TRACEREG_SZ));
574 /* Zero terminate the stack backtrace. */
576 t->kregs->u_regs[UREG_FP] =
577 ((unsigned long) child_sf) - STACK_BIAS;
579 t->flags |= ((long)ASI_P << TI_FLAG_CURRENT_DS_SHIFT);
580 t->kregs->u_regs[UREG_G6] = (unsigned long) t;
581 t->kregs->u_regs[UREG_G4] = (unsigned long) t->task;
583 if (t->flags & _TIF_32BIT) {
584 sp &= 0x00000000ffffffffUL;
585 regs->u_regs[UREG_FP] &= 0x00000000ffffffffUL;
587 t->kregs->u_regs[UREG_FP] = sp;
588 t->flags |= ((long)ASI_AIUS << TI_FLAG_CURRENT_DS_SHIFT);
589 if (sp != regs->u_regs[UREG_FP]) {
592 csp = clone_stackframe(sp, regs->u_regs[UREG_FP]);
595 t->kregs->u_regs[UREG_FP] = csp;
601 /* Set the return value for the child. */
602 t->kregs->u_regs[UREG_I0] = current->pid;
603 t->kregs->u_regs[UREG_I1] = 1;
605 /* Set the second return value for the parent. */
606 regs->u_regs[UREG_I1] = 0;
608 if (clone_flags & CLONE_SETTLS)
609 t->kregs->u_regs[UREG_G7] = regs->u_regs[UREG_I3];
615 * This is the mechanism for creating a new kernel thread.
617 * NOTE! Only a kernel-only process(ie the swapper or direct descendants
618 * who haven't done an "execve()") should use this: it will work within
619 * a system call from a "real" process, but the process memory space will
620 * not be freed until both the parent and the child have exited.
622 pid_t kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
626 /* If the parent runs before fn(arg) is called by the child,
627 * the input registers of this function can be clobbered.
628 * So we stash 'fn' and 'arg' into global registers which
629 * will not be modified by the parent.
631 __asm__ __volatile__("mov %4, %%g2\n\t" /* Save FN into global */
632 "mov %5, %%g3\n\t" /* Save ARG into global */
633 "mov %1, %%g1\n\t" /* Clone syscall nr. */
634 "mov %2, %%o0\n\t" /* Clone flags. */
635 "mov 0, %%o1\n\t" /* usp arg == 0 */
636 "t 0x6d\n\t" /* Linux/Sparc clone(). */
637 "brz,a,pn %%o1, 1f\n\t" /* Parent, just return. */
639 "jmpl %%g2, %%o7\n\t" /* Call the function. */
640 " mov %%g3, %%o0\n\t" /* Set arg in delay. */
642 "t 0x6d\n\t" /* Linux/Sparc exit(). */
643 /* Notreached by child. */
646 "i" (__NR_clone), "r" (flags | CLONE_VM | CLONE_UNTRACED),
647 "i" (__NR_exit), "r" (fn), "r" (arg) :
648 "g1", "g2", "g3", "o0", "o1", "memory", "cc");
651 EXPORT_SYMBOL(kernel_thread);
655 unsigned int pr_regs[32];
656 unsigned long pr_dregs[16];
658 unsigned int __unused;
660 unsigned char pr_qcnt;
661 unsigned char pr_q_entrysize;
663 unsigned int pr_q[64];
667 * fill in the fpu structure for a core dump.
669 int dump_fpu (struct pt_regs * regs, elf_fpregset_t * fpregs)
671 unsigned long *kfpregs = current_thread_info()->fpregs;
672 unsigned long fprs = current_thread_info()->fpsaved[0];
674 if (test_thread_flag(TIF_32BIT)) {
675 elf_fpregset_t32 *fpregs32 = (elf_fpregset_t32 *)fpregs;
678 memcpy(&fpregs32->pr_fr.pr_regs[0], kfpregs,
679 sizeof(unsigned int) * 32);
681 memset(&fpregs32->pr_fr.pr_regs[0], 0,
682 sizeof(unsigned int) * 32);
683 fpregs32->pr_qcnt = 0;
684 fpregs32->pr_q_entrysize = 8;
685 memset(&fpregs32->pr_q[0], 0,
686 (sizeof(unsigned int) * 64));
687 if (fprs & FPRS_FEF) {
688 fpregs32->pr_fsr = (unsigned int) current_thread_info()->xfsr[0];
691 fpregs32->pr_fsr = 0;
696 memcpy(&fpregs->pr_regs[0], kfpregs,
697 sizeof(unsigned int) * 32);
699 memset(&fpregs->pr_regs[0], 0,
700 sizeof(unsigned int) * 32);
702 memcpy(&fpregs->pr_regs[16], kfpregs+16,
703 sizeof(unsigned int) * 32);
705 memset(&fpregs->pr_regs[16], 0,
706 sizeof(unsigned int) * 32);
707 if(fprs & FPRS_FEF) {
708 fpregs->pr_fsr = current_thread_info()->xfsr[0];
709 fpregs->pr_gsr = current_thread_info()->gsr[0];
711 fpregs->pr_fsr = fpregs->pr_gsr = 0;
713 fpregs->pr_fprs = fprs;
717 EXPORT_SYMBOL(dump_fpu);
720 * sparc_execve() executes a new program after the asm stub has set
721 * things up for us. This should basically do what I want it to.
723 asmlinkage int sparc_execve(struct pt_regs *regs)
728 /* User register window flush is done by entry.S */
730 /* Check for indirect call. */
731 if (regs->u_regs[UREG_G1] == 0)
734 filename = getname((char __user *)regs->u_regs[base + UREG_I0]);
735 error = PTR_ERR(filename);
736 if (IS_ERR(filename))
738 error = do_execve(filename,
739 (const char __user *const __user *)
740 regs->u_regs[base + UREG_I1],
741 (const char __user *const __user *)
742 regs->u_regs[base + UREG_I2], regs);
746 current_thread_info()->xfsr[0] = 0;
747 current_thread_info()->fpsaved[0] = 0;
748 regs->tstate &= ~TSTATE_PEF;
754 unsigned long get_wchan(struct task_struct *task)
756 unsigned long pc, fp, bias = 0;
757 struct thread_info *tp;
758 struct reg_window *rw;
759 unsigned long ret = 0;
762 if (!task || task == current ||
763 task->state == TASK_RUNNING)
766 tp = task_thread_info(task);
768 fp = task_thread_info(task)->ksp + bias;
771 if (!kstack_valid(tp, fp))
773 rw = (struct reg_window *) fp;
775 if (!in_sched_functions(pc)) {
779 fp = rw->ins[6] + bias;
780 } while (++count < 16);