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-rw-r--r--arch/sparc/kernel/process_64.c812
1 files changed, 812 insertions, 0 deletions
diff --git a/arch/sparc/kernel/process_64.c b/arch/sparc/kernel/process_64.c
new file mode 100644
index 000000000000..d5e2acef9877
--- /dev/null
+++ b/arch/sparc/kernel/process_64.c
@@ -0,0 +1,812 @@
+/* arch/sparc64/kernel/process.c
+ *
+ * Copyright (C) 1995, 1996, 2008 David S. Miller (davem@davemloft.net)
+ * Copyright (C) 1996 Eddie C. Dost (ecd@skynet.be)
+ * Copyright (C) 1997, 1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
+ */
+
+/*
+ * This file handles the architecture-dependent parts of process handling..
+ */
+
+#include <stdarg.h>
+
+#include <linux/errno.h>
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/fs.h>
+#include <linux/smp.h>
+#include <linux/stddef.h>
+#include <linux/ptrace.h>
+#include <linux/slab.h>
+#include <linux/user.h>
+#include <linux/delay.h>
+#include <linux/compat.h>
+#include <linux/tick.h>
+#include <linux/init.h>
+#include <linux/cpu.h>
+#include <linux/elfcore.h>
+#include <linux/sysrq.h>
+
+#include <asm/uaccess.h>
+#include <asm/system.h>
+#include <asm/page.h>
+#include <asm/pgalloc.h>
+#include <asm/pgtable.h>
+#include <asm/processor.h>
+#include <asm/pstate.h>
+#include <asm/elf.h>
+#include <asm/fpumacro.h>
+#include <asm/head.h>
+#include <asm/cpudata.h>
+#include <asm/mmu_context.h>
+#include <asm/unistd.h>
+#include <asm/hypervisor.h>
+#include <asm/syscalls.h>
+#include <asm/irq_regs.h>
+#include <asm/smp.h>
+
+#include "kstack.h"
+
+static void sparc64_yield(int cpu)
+{
+ if (tlb_type != hypervisor)
+ return;
+
+ clear_thread_flag(TIF_POLLING_NRFLAG);
+ smp_mb__after_clear_bit();
+
+ while (!need_resched() && !cpu_is_offline(cpu)) {
+ unsigned long pstate;
+
+ /* Disable interrupts. */
+ __asm__ __volatile__(
+ "rdpr %%pstate, %0\n\t"
+ "andn %0, %1, %0\n\t"
+ "wrpr %0, %%g0, %%pstate"
+ : "=&r" (pstate)
+ : "i" (PSTATE_IE));
+
+ if (!need_resched() && !cpu_is_offline(cpu))
+ sun4v_cpu_yield();
+
+ /* Re-enable interrupts. */
+ __asm__ __volatile__(
+ "rdpr %%pstate, %0\n\t"
+ "or %0, %1, %0\n\t"
+ "wrpr %0, %%g0, %%pstate"
+ : "=&r" (pstate)
+ : "i" (PSTATE_IE));
+ }
+
+ set_thread_flag(TIF_POLLING_NRFLAG);
+}
+
+/* The idle loop on sparc64. */
+void cpu_idle(void)
+{
+ int cpu = smp_processor_id();
+
+ set_thread_flag(TIF_POLLING_NRFLAG);
+
+ while(1) {
+ tick_nohz_stop_sched_tick(1);
+
+ while (!need_resched() && !cpu_is_offline(cpu))
+ sparc64_yield(cpu);
+
+ tick_nohz_restart_sched_tick();
+
+ preempt_enable_no_resched();
+
+#ifdef CONFIG_HOTPLUG_CPU
+ if (cpu_is_offline(cpu))
+ cpu_play_dead();
+#endif
+
+ schedule();
+ preempt_disable();
+ }
+}
+
+#ifdef CONFIG_COMPAT
+static void show_regwindow32(struct pt_regs *regs)
+{
+ struct reg_window32 __user *rw;
+ struct reg_window32 r_w;
+ mm_segment_t old_fs;
+
+ __asm__ __volatile__ ("flushw");
+ rw = compat_ptr((unsigned)regs->u_regs[14]);
+ old_fs = get_fs();
+ set_fs (USER_DS);
+ if (copy_from_user (&r_w, rw, sizeof(r_w))) {
+ set_fs (old_fs);
+ return;
+ }
+
+ set_fs (old_fs);
+ printk("l0: %08x l1: %08x l2: %08x l3: %08x "
+ "l4: %08x l5: %08x l6: %08x l7: %08x\n",
+ r_w.locals[0], r_w.locals[1], r_w.locals[2], r_w.locals[3],
+ r_w.locals[4], r_w.locals[5], r_w.locals[6], r_w.locals[7]);
+ printk("i0: %08x i1: %08x i2: %08x i3: %08x "
+ "i4: %08x i5: %08x i6: %08x i7: %08x\n",
+ r_w.ins[0], r_w.ins[1], r_w.ins[2], r_w.ins[3],
+ r_w.ins[4], r_w.ins[5], r_w.ins[6], r_w.ins[7]);
+}
+#else
+#define show_regwindow32(regs) do { } while (0)
+#endif
+
+static void show_regwindow(struct pt_regs *regs)
+{
+ struct reg_window __user *rw;
+ struct reg_window *rwk;
+ struct reg_window r_w;
+ mm_segment_t old_fs;
+
+ if ((regs->tstate & TSTATE_PRIV) || !(test_thread_flag(TIF_32BIT))) {
+ __asm__ __volatile__ ("flushw");
+ rw = (struct reg_window __user *)
+ (regs->u_regs[14] + STACK_BIAS);
+ rwk = (struct reg_window *)
+ (regs->u_regs[14] + STACK_BIAS);
+ if (!(regs->tstate & TSTATE_PRIV)) {
+ old_fs = get_fs();
+ set_fs (USER_DS);
+ if (copy_from_user (&r_w, rw, sizeof(r_w))) {
+ set_fs (old_fs);
+ return;
+ }
+ rwk = &r_w;
+ set_fs (old_fs);
+ }
+ } else {
+ show_regwindow32(regs);
+ return;
+ }
+ printk("l0: %016lx l1: %016lx l2: %016lx l3: %016lx\n",
+ rwk->locals[0], rwk->locals[1], rwk->locals[2], rwk->locals[3]);
+ printk("l4: %016lx l5: %016lx l6: %016lx l7: %016lx\n",
+ rwk->locals[4], rwk->locals[5], rwk->locals[6], rwk->locals[7]);
+ printk("i0: %016lx i1: %016lx i2: %016lx i3: %016lx\n",
+ rwk->ins[0], rwk->ins[1], rwk->ins[2], rwk->ins[3]);
+ printk("i4: %016lx i5: %016lx i6: %016lx i7: %016lx\n",
+ rwk->ins[4], rwk->ins[5], rwk->ins[6], rwk->ins[7]);
+ if (regs->tstate & TSTATE_PRIV)
+ printk("I7: <%pS>\n", (void *) rwk->ins[7]);
+}
+
+void show_regs(struct pt_regs *regs)
+{
+ printk("TSTATE: %016lx TPC: %016lx TNPC: %016lx Y: %08x %s\n", regs->tstate,
+ regs->tpc, regs->tnpc, regs->y, print_tainted());
+ printk("TPC: <%pS>\n", (void *) regs->tpc);
+ printk("g0: %016lx g1: %016lx g2: %016lx g3: %016lx\n",
+ regs->u_regs[0], regs->u_regs[1], regs->u_regs[2],
+ regs->u_regs[3]);
+ printk("g4: %016lx g5: %016lx g6: %016lx g7: %016lx\n",
+ regs->u_regs[4], regs->u_regs[5], regs->u_regs[6],
+ regs->u_regs[7]);
+ printk("o0: %016lx o1: %016lx o2: %016lx o3: %016lx\n",
+ regs->u_regs[8], regs->u_regs[9], regs->u_regs[10],
+ regs->u_regs[11]);
+ printk("o4: %016lx o5: %016lx sp: %016lx ret_pc: %016lx\n",
+ regs->u_regs[12], regs->u_regs[13], regs->u_regs[14],
+ regs->u_regs[15]);
+ printk("RPC: <%pS>\n", (void *) regs->u_regs[15]);
+ show_regwindow(regs);
+}
+
+struct global_reg_snapshot global_reg_snapshot[NR_CPUS];
+static DEFINE_SPINLOCK(global_reg_snapshot_lock);
+
+static void __global_reg_self(struct thread_info *tp, struct pt_regs *regs,
+ int this_cpu)
+{
+ flushw_all();
+
+ global_reg_snapshot[this_cpu].tstate = regs->tstate;
+ global_reg_snapshot[this_cpu].tpc = regs->tpc;
+ global_reg_snapshot[this_cpu].tnpc = regs->tnpc;
+ global_reg_snapshot[this_cpu].o7 = regs->u_regs[UREG_I7];
+
+ if (regs->tstate & TSTATE_PRIV) {
+ struct reg_window *rw;
+
+ rw = (struct reg_window *)
+ (regs->u_regs[UREG_FP] + STACK_BIAS);
+ if (kstack_valid(tp, (unsigned long) rw)) {
+ global_reg_snapshot[this_cpu].i7 = rw->ins[7];
+ rw = (struct reg_window *)
+ (rw->ins[6] + STACK_BIAS);
+ if (kstack_valid(tp, (unsigned long) rw))
+ global_reg_snapshot[this_cpu].rpc = rw->ins[7];
+ }
+ } else {
+ global_reg_snapshot[this_cpu].i7 = 0;
+ global_reg_snapshot[this_cpu].rpc = 0;
+ }
+ global_reg_snapshot[this_cpu].thread = tp;
+}
+
+/* In order to avoid hangs we do not try to synchronize with the
+ * global register dump client cpus. The last store they make is to
+ * the thread pointer, so do a short poll waiting for that to become
+ * non-NULL.
+ */
+static void __global_reg_poll(struct global_reg_snapshot *gp)
+{
+ int limit = 0;
+
+ while (!gp->thread && ++limit < 100) {
+ barrier();
+ udelay(1);
+ }
+}
+
+void __trigger_all_cpu_backtrace(void)
+{
+ struct thread_info *tp = current_thread_info();
+ struct pt_regs *regs = get_irq_regs();
+ unsigned long flags;
+ int this_cpu, cpu;
+
+ if (!regs)
+ regs = tp->kregs;
+
+ spin_lock_irqsave(&global_reg_snapshot_lock, flags);
+
+ memset(global_reg_snapshot, 0, sizeof(global_reg_snapshot));
+
+ this_cpu = raw_smp_processor_id();
+
+ __global_reg_self(tp, regs, this_cpu);
+
+ smp_fetch_global_regs();
+
+ for_each_online_cpu(cpu) {
+ struct global_reg_snapshot *gp = &global_reg_snapshot[cpu];
+
+ __global_reg_poll(gp);
+
+ tp = gp->thread;
+ printk("%c CPU[%3d]: TSTATE[%016lx] TPC[%016lx] TNPC[%016lx] TASK[%s:%d]\n",
+ (cpu == this_cpu ? '*' : ' '), cpu,
+ gp->tstate, gp->tpc, gp->tnpc,
+ ((tp && tp->task) ? tp->task->comm : "NULL"),
+ ((tp && tp->task) ? tp->task->pid : -1));
+
+ if (gp->tstate & TSTATE_PRIV) {
+ printk(" TPC[%pS] O7[%pS] I7[%pS] RPC[%pS]\n",
+ (void *) gp->tpc,
+ (void *) gp->o7,
+ (void *) gp->i7,
+ (void *) gp->rpc);
+ } else {
+ printk(" TPC[%lx] O7[%lx] I7[%lx] RPC[%lx]\n",
+ gp->tpc, gp->o7, gp->i7, gp->rpc);
+ }
+ }
+
+ memset(global_reg_snapshot, 0, sizeof(global_reg_snapshot));
+
+ spin_unlock_irqrestore(&global_reg_snapshot_lock, flags);
+}
+
+#ifdef CONFIG_MAGIC_SYSRQ
+
+static void sysrq_handle_globreg(int key, struct tty_struct *tty)
+{
+ __trigger_all_cpu_backtrace();
+}
+
+static struct sysrq_key_op sparc_globalreg_op = {
+ .handler = sysrq_handle_globreg,
+ .help_msg = "Globalregs",
+ .action_msg = "Show Global CPU Regs",
+};
+
+static int __init sparc_globreg_init(void)
+{
+ return register_sysrq_key('y', &sparc_globalreg_op);
+}
+
+core_initcall(sparc_globreg_init);
+
+#endif
+
+unsigned long thread_saved_pc(struct task_struct *tsk)
+{
+ struct thread_info *ti = task_thread_info(tsk);
+ unsigned long ret = 0xdeadbeefUL;
+
+ if (ti && ti->ksp) {
+ unsigned long *sp;
+ sp = (unsigned long *)(ti->ksp + STACK_BIAS);
+ if (((unsigned long)sp & (sizeof(long) - 1)) == 0UL &&
+ sp[14]) {
+ unsigned long *fp;
+ fp = (unsigned long *)(sp[14] + STACK_BIAS);
+ if (((unsigned long)fp & (sizeof(long) - 1)) == 0UL)
+ ret = fp[15];
+ }
+ }
+ return ret;
+}
+
+/* Free current thread data structures etc.. */
+void exit_thread(void)
+{
+ struct thread_info *t = current_thread_info();
+
+ if (t->utraps) {
+ if (t->utraps[0] < 2)
+ kfree (t->utraps);
+ else
+ t->utraps[0]--;
+ }
+
+ if (test_and_clear_thread_flag(TIF_PERFCTR)) {
+ t->user_cntd0 = t->user_cntd1 = NULL;
+ t->pcr_reg = 0;
+ write_pcr(0);
+ }
+}
+
+void flush_thread(void)
+{
+ struct thread_info *t = current_thread_info();
+ struct mm_struct *mm;
+
+ if (test_ti_thread_flag(t, TIF_ABI_PENDING)) {
+ clear_ti_thread_flag(t, TIF_ABI_PENDING);
+ if (test_ti_thread_flag(t, TIF_32BIT))
+ clear_ti_thread_flag(t, TIF_32BIT);
+ else
+ set_ti_thread_flag(t, TIF_32BIT);
+ }
+
+ mm = t->task->mm;
+ if (mm)
+ tsb_context_switch(mm);
+
+ set_thread_wsaved(0);
+
+ /* Turn off performance counters if on. */
+ if (test_and_clear_thread_flag(TIF_PERFCTR)) {
+ t->user_cntd0 = t->user_cntd1 = NULL;
+ t->pcr_reg = 0;
+ write_pcr(0);
+ }
+
+ /* Clear FPU register state. */
+ t->fpsaved[0] = 0;
+
+ if (get_thread_current_ds() != ASI_AIUS)
+ set_fs(USER_DS);
+}
+
+/* It's a bit more tricky when 64-bit tasks are involved... */
+static unsigned long clone_stackframe(unsigned long csp, unsigned long psp)
+{
+ unsigned long fp, distance, rval;
+
+ if (!(test_thread_flag(TIF_32BIT))) {
+ csp += STACK_BIAS;
+ psp += STACK_BIAS;
+ __get_user(fp, &(((struct reg_window __user *)psp)->ins[6]));
+ fp += STACK_BIAS;
+ } else
+ __get_user(fp, &(((struct reg_window32 __user *)psp)->ins[6]));
+
+ /* Now 8-byte align the stack as this is mandatory in the
+ * Sparc ABI due to how register windows work. This hides
+ * the restriction from thread libraries etc. -DaveM
+ */
+ csp &= ~7UL;
+
+ distance = fp - psp;
+ rval = (csp - distance);
+ if (copy_in_user((void __user *) rval, (void __user *) psp, distance))
+ rval = 0;
+ else if (test_thread_flag(TIF_32BIT)) {
+ if (put_user(((u32)csp),
+ &(((struct reg_window32 __user *)rval)->ins[6])))
+ rval = 0;
+ } else {
+ if (put_user(((u64)csp - STACK_BIAS),
+ &(((struct reg_window __user *)rval)->ins[6])))
+ rval = 0;
+ else
+ rval = rval - STACK_BIAS;
+ }
+
+ return rval;
+}
+
+/* Standard stuff. */
+static inline void shift_window_buffer(int first_win, int last_win,
+ struct thread_info *t)
+{
+ int i;
+
+ for (i = first_win; i < last_win; i++) {
+ t->rwbuf_stkptrs[i] = t->rwbuf_stkptrs[i+1];
+ memcpy(&t->reg_window[i], &t->reg_window[i+1],
+ sizeof(struct reg_window));
+ }
+}
+
+void synchronize_user_stack(void)
+{
+ struct thread_info *t = current_thread_info();
+ unsigned long window;
+
+ flush_user_windows();
+ if ((window = get_thread_wsaved()) != 0) {
+ int winsize = sizeof(struct reg_window);
+ int bias = 0;
+
+ if (test_thread_flag(TIF_32BIT))
+ winsize = sizeof(struct reg_window32);
+ else
+ bias = STACK_BIAS;
+
+ window -= 1;
+ do {
+ unsigned long sp = (t->rwbuf_stkptrs[window] + bias);
+ struct reg_window *rwin = &t->reg_window[window];
+
+ if (!copy_to_user((char __user *)sp, rwin, winsize)) {
+ shift_window_buffer(window, get_thread_wsaved() - 1, t);
+ set_thread_wsaved(get_thread_wsaved() - 1);
+ }
+ } while (window--);
+ }
+}
+
+static void stack_unaligned(unsigned long sp)
+{
+ siginfo_t info;
+
+ info.si_signo = SIGBUS;
+ info.si_errno = 0;
+ info.si_code = BUS_ADRALN;
+ info.si_addr = (void __user *) sp;
+ info.si_trapno = 0;
+ force_sig_info(SIGBUS, &info, current);
+}
+
+void fault_in_user_windows(void)
+{
+ struct thread_info *t = current_thread_info();
+ unsigned long window;
+ int winsize = sizeof(struct reg_window);
+ int bias = 0;
+
+ if (test_thread_flag(TIF_32BIT))
+ winsize = sizeof(struct reg_window32);
+ else
+ bias = STACK_BIAS;
+
+ flush_user_windows();
+ window = get_thread_wsaved();
+
+ if (likely(window != 0)) {
+ window -= 1;
+ do {
+ unsigned long sp = (t->rwbuf_stkptrs[window] + bias);
+ struct reg_window *rwin = &t->reg_window[window];
+
+ if (unlikely(sp & 0x7UL))
+ stack_unaligned(sp);
+
+ if (unlikely(copy_to_user((char __user *)sp,
+ rwin, winsize)))
+ goto barf;
+ } while (window--);
+ }
+ set_thread_wsaved(0);
+ return;
+
+barf:
+ set_thread_wsaved(window + 1);
+ do_exit(SIGILL);
+}
+
+asmlinkage long sparc_do_fork(unsigned long clone_flags,
+ unsigned long stack_start,
+ struct pt_regs *regs,
+ unsigned long stack_size)
+{
+ int __user *parent_tid_ptr, *child_tid_ptr;
+ unsigned long orig_i1 = regs->u_regs[UREG_I1];
+ long ret;
+
+#ifdef CONFIG_COMPAT
+ if (test_thread_flag(TIF_32BIT)) {
+ parent_tid_ptr = compat_ptr(regs->u_regs[UREG_I2]);
+ child_tid_ptr = compat_ptr(regs->u_regs[UREG_I4]);
+ } else
+#endif
+ {
+ parent_tid_ptr = (int __user *) regs->u_regs[UREG_I2];
+ child_tid_ptr = (int __user *) regs->u_regs[UREG_I4];
+ }
+
+ ret = do_fork(clone_flags, stack_start,
+ regs, stack_size,
+ parent_tid_ptr, child_tid_ptr);
+
+ /* If we get an error and potentially restart the system
+ * call, we're screwed because copy_thread() clobbered
+ * the parent's %o1. So detect that case and restore it
+ * here.
+ */
+ if ((unsigned long)ret >= -ERESTART_RESTARTBLOCK)
+ regs->u_regs[UREG_I1] = orig_i1;
+
+ return ret;
+}
+
+/* Copy a Sparc thread. The fork() return value conventions
+ * under SunOS are nothing short of bletcherous:
+ * Parent --> %o0 == childs pid, %o1 == 0
+ * Child --> %o0 == parents pid, %o1 == 1
+ */
+int copy_thread(int nr, unsigned long clone_flags, unsigned long sp,
+ unsigned long unused,
+ struct task_struct *p, struct pt_regs *regs)
+{
+ struct thread_info *t = task_thread_info(p);
+ struct sparc_stackf *parent_sf;
+ unsigned long child_stack_sz;
+ char *child_trap_frame;
+ int kernel_thread;
+
+ kernel_thread = (regs->tstate & TSTATE_PRIV) ? 1 : 0;
+ parent_sf = ((struct sparc_stackf *) regs) - 1;
+
+ /* Calculate offset to stack_frame & pt_regs */
+ child_stack_sz = ((STACKFRAME_SZ + TRACEREG_SZ) +
+ (kernel_thread ? STACKFRAME_SZ : 0));
+ child_trap_frame = (task_stack_page(p) +
+ (THREAD_SIZE - child_stack_sz));
+ memcpy(child_trap_frame, parent_sf, child_stack_sz);
+
+ t->flags = (t->flags & ~((0xffUL << TI_FLAG_CWP_SHIFT) |
+ (0xffUL << TI_FLAG_CURRENT_DS_SHIFT))) |
+ (((regs->tstate + 1) & TSTATE_CWP) << TI_FLAG_CWP_SHIFT);
+ t->new_child = 1;
+ t->ksp = ((unsigned long) child_trap_frame) - STACK_BIAS;
+ t->kregs = (struct pt_regs *) (child_trap_frame +
+ sizeof(struct sparc_stackf));
+ t->fpsaved[0] = 0;
+
+ if (kernel_thread) {
+ struct sparc_stackf *child_sf = (struct sparc_stackf *)
+ (child_trap_frame + (STACKFRAME_SZ + TRACEREG_SZ));
+
+ /* Zero terminate the stack backtrace. */
+ child_sf->fp = NULL;
+ t->kregs->u_regs[UREG_FP] =
+ ((unsigned long) child_sf) - STACK_BIAS;
+
+ /* Special case, if we are spawning a kernel thread from
+ * a userspace task (usermode helper, NFS or similar), we
+ * must disable performance counters in the child because
+ * the address space and protection realm are changing.
+ */
+ if (t->flags & _TIF_PERFCTR) {
+ t->user_cntd0 = t->user_cntd1 = NULL;
+ t->pcr_reg = 0;
+ t->flags &= ~_TIF_PERFCTR;
+ }
+ t->flags |= ((long)ASI_P << TI_FLAG_CURRENT_DS_SHIFT);
+ t->kregs->u_regs[UREG_G6] = (unsigned long) t;
+ t->kregs->u_regs[UREG_G4] = (unsigned long) t->task;
+ } else {
+ if (t->flags & _TIF_32BIT) {
+ sp &= 0x00000000ffffffffUL;
+ regs->u_regs[UREG_FP] &= 0x00000000ffffffffUL;
+ }
+ t->kregs->u_regs[UREG_FP] = sp;
+ t->flags |= ((long)ASI_AIUS << TI_FLAG_CURRENT_DS_SHIFT);
+ if (sp != regs->u_regs[UREG_FP]) {
+ unsigned long csp;
+
+ csp = clone_stackframe(sp, regs->u_regs[UREG_FP]);
+ if (!csp)
+ return -EFAULT;
+ t->kregs->u_regs[UREG_FP] = csp;
+ }
+ if (t->utraps)
+ t->utraps[0]++;
+ }
+
+ /* Set the return value for the child. */
+ t->kregs->u_regs[UREG_I0] = current->pid;
+ t->kregs->u_regs[UREG_I1] = 1;
+
+ /* Set the second return value for the parent. */
+ regs->u_regs[UREG_I1] = 0;
+
+ if (clone_flags & CLONE_SETTLS)
+ t->kregs->u_regs[UREG_G7] = regs->u_regs[UREG_I3];
+
+ return 0;
+}
+
+/*
+ * This is the mechanism for creating a new kernel thread.
+ *
+ * NOTE! Only a kernel-only process(ie the swapper or direct descendants
+ * who haven't done an "execve()") should use this: it will work within
+ * a system call from a "real" process, but the process memory space will
+ * not be freed until both the parent and the child have exited.
+ */
+pid_t kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
+{
+ long retval;
+
+ /* If the parent runs before fn(arg) is called by the child,
+ * the input registers of this function can be clobbered.
+ * So we stash 'fn' and 'arg' into global registers which
+ * will not be modified by the parent.
+ */
+ __asm__ __volatile__("mov %4, %%g2\n\t" /* Save FN into global */
+ "mov %5, %%g3\n\t" /* Save ARG into global */
+ "mov %1, %%g1\n\t" /* Clone syscall nr. */
+ "mov %2, %%o0\n\t" /* Clone flags. */
+ "mov 0, %%o1\n\t" /* usp arg == 0 */
+ "t 0x6d\n\t" /* Linux/Sparc clone(). */
+ "brz,a,pn %%o1, 1f\n\t" /* Parent, just return. */
+ " mov %%o0, %0\n\t"
+ "jmpl %%g2, %%o7\n\t" /* Call the function. */
+ " mov %%g3, %%o0\n\t" /* Set arg in delay. */
+ "mov %3, %%g1\n\t"
+ "t 0x6d\n\t" /* Linux/Sparc exit(). */
+ /* Notreached by child. */
+ "1:" :
+ "=r" (retval) :
+ "i" (__NR_clone), "r" (flags | CLONE_VM | CLONE_UNTRACED),
+ "i" (__NR_exit), "r" (fn), "r" (arg) :
+ "g1", "g2", "g3", "o0", "o1", "memory", "cc");
+ return retval;
+}
+
+typedef struct {
+ union {
+ unsigned int pr_regs[32];
+ unsigned long pr_dregs[16];
+ } pr_fr;
+ unsigned int __unused;
+ unsigned int pr_fsr;
+ unsigned char pr_qcnt;
+ unsigned char pr_q_entrysize;
+ unsigned char pr_en;
+ unsigned int pr_q[64];
+} elf_fpregset_t32;
+
+/*
+ * fill in the fpu structure for a core dump.
+ */
+int dump_fpu (struct pt_regs * regs, elf_fpregset_t * fpregs)
+{
+ unsigned long *kfpregs = current_thread_info()->fpregs;
+ unsigned long fprs = current_thread_info()->fpsaved[0];
+
+ if (test_thread_flag(TIF_32BIT)) {
+ elf_fpregset_t32 *fpregs32 = (elf_fpregset_t32 *)fpregs;
+
+ if (fprs & FPRS_DL)
+ memcpy(&fpregs32->pr_fr.pr_regs[0], kfpregs,
+ sizeof(unsigned int) * 32);
+ else
+ memset(&fpregs32->pr_fr.pr_regs[0], 0,
+ sizeof(unsigned int) * 32);
+ fpregs32->pr_qcnt = 0;
+ fpregs32->pr_q_entrysize = 8;
+ memset(&fpregs32->pr_q[0], 0,
+ (sizeof(unsigned int) * 64));
+ if (fprs & FPRS_FEF) {
+ fpregs32->pr_fsr = (unsigned int) current_thread_info()->xfsr[0];
+ fpregs32->pr_en = 1;
+ } else {
+ fpregs32->pr_fsr = 0;
+ fpregs32->pr_en = 0;
+ }
+ } else {
+ if(fprs & FPRS_DL)
+ memcpy(&fpregs->pr_regs[0], kfpregs,
+ sizeof(unsigned int) * 32);
+ else
+ memset(&fpregs->pr_regs[0], 0,
+ sizeof(unsigned int) * 32);
+ if(fprs & FPRS_DU)
+ memcpy(&fpregs->pr_regs[16], kfpregs+16,
+ sizeof(unsigned int) * 32);
+ else
+ memset(&fpregs->pr_regs[16], 0,
+ sizeof(unsigned int) * 32);
+ if(fprs & FPRS_FEF) {
+ fpregs->pr_fsr = current_thread_info()->xfsr[0];
+ fpregs->pr_gsr = current_thread_info()->gsr[0];
+ } else {
+ fpregs->pr_fsr = fpregs->pr_gsr = 0;
+ }
+ fpregs->pr_fprs = fprs;
+ }
+ return 1;
+}
+
+/*
+ * sparc_execve() executes a new program after the asm stub has set
+ * things up for us. This should basically do what I want it to.
+ */
+asmlinkage int sparc_execve(struct pt_regs *regs)
+{
+ int error, base = 0;
+ char *filename;
+
+ /* User register window flush is done by entry.S */
+
+ /* Check for indirect call. */
+ if (regs->u_regs[UREG_G1] == 0)
+ base = 1;
+
+ filename = getname((char __user *)regs->u_regs[base + UREG_I0]);
+ error = PTR_ERR(filename);
+ if (IS_ERR(filename))
+ goto out;
+ error = do_execve(filename,
+ (char __user * __user *)
+ regs->u_regs[base + UREG_I1],
+ (char __user * __user *)
+ regs->u_regs[base + UREG_I2], regs);
+ putname(filename);
+ if (!error) {
+ fprs_write(0);
+ current_thread_info()->xfsr[0] = 0;
+ current_thread_info()->fpsaved[0] = 0;
+ regs->tstate &= ~TSTATE_PEF;
+ }
+out:
+ return error;
+}
+
+unsigned long get_wchan(struct task_struct *task)
+{
+ unsigned long pc, fp, bias = 0;
+ struct thread_info *tp;
+ struct reg_window *rw;
+ unsigned long ret = 0;
+ int count = 0;
+
+ if (!task || task == current ||
+ task->state == TASK_RUNNING)
+ goto out;
+
+ tp = task_thread_info(task);
+ bias = STACK_BIAS;
+ fp = task_thread_info(task)->ksp + bias;
+
+ do {
+ if (!kstack_valid(tp, fp))
+ break;
+ rw = (struct reg_window *) fp;
+ pc = rw->ins[7];
+ if (!in_sched_functions(pc)) {
+ ret = pc;
+ goto out;
+ }
+ fp = rw->ins[6] + bias;
+ } while (++count < 16);
+
+out:
+ return ret;
+}