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-rw-r--r--arch/ia64/kernel/process.c800
1 files changed, 800 insertions, 0 deletions
diff --git a/arch/ia64/kernel/process.c b/arch/ia64/kernel/process.c
new file mode 100644
index 000000000000..91293388dd29
--- /dev/null
+++ b/arch/ia64/kernel/process.c
@@ -0,0 +1,800 @@
+/*
+ * Architecture-specific setup.
+ *
+ * Copyright (C) 1998-2003 Hewlett-Packard Co
+ * David Mosberger-Tang <davidm@hpl.hp.com>
+ */
+#define __KERNEL_SYSCALLS__ /* see <asm/unistd.h> */
+#include <linux/config.h>
+
+#include <linux/cpu.h>
+#include <linux/pm.h>
+#include <linux/elf.h>
+#include <linux/errno.h>
+#include <linux/kallsyms.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/notifier.h>
+#include <linux/personality.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/smp_lock.h>
+#include <linux/stddef.h>
+#include <linux/thread_info.h>
+#include <linux/unistd.h>
+#include <linux/efi.h>
+#include <linux/interrupt.h>
+#include <linux/delay.h>
+
+#include <asm/cpu.h>
+#include <asm/delay.h>
+#include <asm/elf.h>
+#include <asm/ia32.h>
+#include <asm/irq.h>
+#include <asm/pgalloc.h>
+#include <asm/processor.h>
+#include <asm/sal.h>
+#include <asm/tlbflush.h>
+#include <asm/uaccess.h>
+#include <asm/unwind.h>
+#include <asm/user.h>
+
+#include "entry.h"
+
+#ifdef CONFIG_PERFMON
+# include <asm/perfmon.h>
+#endif
+
+#include "sigframe.h"
+
+void (*ia64_mark_idle)(int);
+static cpumask_t cpu_idle_map;
+
+unsigned long boot_option_idle_override = 0;
+EXPORT_SYMBOL(boot_option_idle_override);
+
+void
+ia64_do_show_stack (struct unw_frame_info *info, void *arg)
+{
+ unsigned long ip, sp, bsp;
+ char buf[128]; /* don't make it so big that it overflows the stack! */
+
+ printk("\nCall Trace:\n");
+ do {
+ unw_get_ip(info, &ip);
+ if (ip == 0)
+ break;
+
+ unw_get_sp(info, &sp);
+ unw_get_bsp(info, &bsp);
+ snprintf(buf, sizeof(buf),
+ " [<%016lx>] %%s\n"
+ " sp=%016lx bsp=%016lx\n",
+ ip, sp, bsp);
+ print_symbol(buf, ip);
+ } while (unw_unwind(info) >= 0);
+}
+
+void
+show_stack (struct task_struct *task, unsigned long *sp)
+{
+ if (!task)
+ unw_init_running(ia64_do_show_stack, NULL);
+ else {
+ struct unw_frame_info info;
+
+ unw_init_from_blocked_task(&info, task);
+ ia64_do_show_stack(&info, NULL);
+ }
+}
+
+void
+dump_stack (void)
+{
+ show_stack(NULL, NULL);
+}
+
+EXPORT_SYMBOL(dump_stack);
+
+void
+show_regs (struct pt_regs *regs)
+{
+ unsigned long ip = regs->cr_iip + ia64_psr(regs)->ri;
+
+ print_modules();
+ printk("\nPid: %d, CPU %d, comm: %20s\n", current->pid, smp_processor_id(), current->comm);
+ printk("psr : %016lx ifs : %016lx ip : [<%016lx>] %s\n",
+ regs->cr_ipsr, regs->cr_ifs, ip, print_tainted());
+ print_symbol("ip is at %s\n", ip);
+ printk("unat: %016lx pfs : %016lx rsc : %016lx\n",
+ regs->ar_unat, regs->ar_pfs, regs->ar_rsc);
+ printk("rnat: %016lx bsps: %016lx pr : %016lx\n",
+ regs->ar_rnat, regs->ar_bspstore, regs->pr);
+ printk("ldrs: %016lx ccv : %016lx fpsr: %016lx\n",
+ regs->loadrs, regs->ar_ccv, regs->ar_fpsr);
+ printk("csd : %016lx ssd : %016lx\n", regs->ar_csd, regs->ar_ssd);
+ printk("b0 : %016lx b6 : %016lx b7 : %016lx\n", regs->b0, regs->b6, regs->b7);
+ printk("f6 : %05lx%016lx f7 : %05lx%016lx\n",
+ regs->f6.u.bits[1], regs->f6.u.bits[0],
+ regs->f7.u.bits[1], regs->f7.u.bits[0]);
+ printk("f8 : %05lx%016lx f9 : %05lx%016lx\n",
+ regs->f8.u.bits[1], regs->f8.u.bits[0],
+ regs->f9.u.bits[1], regs->f9.u.bits[0]);
+ printk("f10 : %05lx%016lx f11 : %05lx%016lx\n",
+ regs->f10.u.bits[1], regs->f10.u.bits[0],
+ regs->f11.u.bits[1], regs->f11.u.bits[0]);
+
+ printk("r1 : %016lx r2 : %016lx r3 : %016lx\n", regs->r1, regs->r2, regs->r3);
+ printk("r8 : %016lx r9 : %016lx r10 : %016lx\n", regs->r8, regs->r9, regs->r10);
+ printk("r11 : %016lx r12 : %016lx r13 : %016lx\n", regs->r11, regs->r12, regs->r13);
+ printk("r14 : %016lx r15 : %016lx r16 : %016lx\n", regs->r14, regs->r15, regs->r16);
+ printk("r17 : %016lx r18 : %016lx r19 : %016lx\n", regs->r17, regs->r18, regs->r19);
+ printk("r20 : %016lx r21 : %016lx r22 : %016lx\n", regs->r20, regs->r21, regs->r22);
+ printk("r23 : %016lx r24 : %016lx r25 : %016lx\n", regs->r23, regs->r24, regs->r25);
+ printk("r26 : %016lx r27 : %016lx r28 : %016lx\n", regs->r26, regs->r27, regs->r28);
+ printk("r29 : %016lx r30 : %016lx r31 : %016lx\n", regs->r29, regs->r30, regs->r31);
+
+ if (user_mode(regs)) {
+ /* print the stacked registers */
+ unsigned long val, *bsp, ndirty;
+ int i, sof, is_nat = 0;
+
+ sof = regs->cr_ifs & 0x7f; /* size of frame */
+ ndirty = (regs->loadrs >> 19);
+ bsp = ia64_rse_skip_regs((unsigned long *) regs->ar_bspstore, ndirty);
+ for (i = 0; i < sof; ++i) {
+ get_user(val, (unsigned long __user *) ia64_rse_skip_regs(bsp, i));
+ printk("r%-3u:%c%016lx%s", 32 + i, is_nat ? '*' : ' ', val,
+ ((i == sof - 1) || (i % 3) == 2) ? "\n" : " ");
+ }
+ } else
+ show_stack(NULL, NULL);
+}
+
+void
+do_notify_resume_user (sigset_t *oldset, struct sigscratch *scr, long in_syscall)
+{
+ if (fsys_mode(current, &scr->pt)) {
+ /* defer signal-handling etc. until we return to privilege-level 0. */
+ if (!ia64_psr(&scr->pt)->lp)
+ ia64_psr(&scr->pt)->lp = 1;
+ return;
+ }
+
+#ifdef CONFIG_PERFMON
+ if (current->thread.pfm_needs_checking)
+ pfm_handle_work();
+#endif
+
+ /* deal with pending signal delivery */
+ if (test_thread_flag(TIF_SIGPENDING))
+ ia64_do_signal(oldset, scr, in_syscall);
+}
+
+static int pal_halt = 1;
+static int __init nohalt_setup(char * str)
+{
+ pal_halt = 0;
+ return 1;
+}
+__setup("nohalt", nohalt_setup);
+
+/*
+ * We use this if we don't have any better idle routine..
+ */
+void
+default_idle (void)
+{
+ unsigned long pmu_active = ia64_getreg(_IA64_REG_PSR) & (IA64_PSR_PP | IA64_PSR_UP);
+
+ while (!need_resched())
+ if (pal_halt && !pmu_active)
+ safe_halt();
+ else
+ cpu_relax();
+}
+
+#ifdef CONFIG_HOTPLUG_CPU
+/* We don't actually take CPU down, just spin without interrupts. */
+static inline void play_dead(void)
+{
+ extern void ia64_cpu_local_tick (void);
+ /* Ack it */
+ __get_cpu_var(cpu_state) = CPU_DEAD;
+
+ /* We shouldn't have to disable interrupts while dead, but
+ * some interrupts just don't seem to go away, and this makes
+ * it "work" for testing purposes. */
+ max_xtp();
+ local_irq_disable();
+ /* Death loop */
+ while (__get_cpu_var(cpu_state) != CPU_UP_PREPARE)
+ cpu_relax();
+
+ /*
+ * Enable timer interrupts from now on
+ * Not required if we put processor in SAL_BOOT_RENDEZ mode.
+ */
+ local_flush_tlb_all();
+ cpu_set(smp_processor_id(), cpu_online_map);
+ wmb();
+ ia64_cpu_local_tick ();
+ local_irq_enable();
+}
+#else
+static inline void play_dead(void)
+{
+ BUG();
+}
+#endif /* CONFIG_HOTPLUG_CPU */
+
+
+void cpu_idle_wait(void)
+{
+ int cpu;
+ cpumask_t map;
+
+ for_each_online_cpu(cpu)
+ cpu_set(cpu, cpu_idle_map);
+
+ wmb();
+ do {
+ ssleep(1);
+ cpus_and(map, cpu_idle_map, cpu_online_map);
+ } while (!cpus_empty(map));
+}
+EXPORT_SYMBOL_GPL(cpu_idle_wait);
+
+void __attribute__((noreturn))
+cpu_idle (void)
+{
+ void (*mark_idle)(int) = ia64_mark_idle;
+ int cpu = smp_processor_id();
+
+ /* endless idle loop with no priority at all */
+ while (1) {
+#ifdef CONFIG_SMP
+ if (!need_resched())
+ min_xtp();
+#endif
+ while (!need_resched()) {
+ void (*idle)(void);
+
+ if (mark_idle)
+ (*mark_idle)(1);
+
+ if (cpu_isset(cpu, cpu_idle_map))
+ cpu_clear(cpu, cpu_idle_map);
+ rmb();
+ idle = pm_idle;
+ if (!idle)
+ idle = default_idle;
+ (*idle)();
+ }
+
+ if (mark_idle)
+ (*mark_idle)(0);
+
+#ifdef CONFIG_SMP
+ normal_xtp();
+#endif
+ schedule();
+ check_pgt_cache();
+ if (cpu_is_offline(smp_processor_id()))
+ play_dead();
+ }
+}
+
+void
+ia64_save_extra (struct task_struct *task)
+{
+#ifdef CONFIG_PERFMON
+ unsigned long info;
+#endif
+
+ if ((task->thread.flags & IA64_THREAD_DBG_VALID) != 0)
+ ia64_save_debug_regs(&task->thread.dbr[0]);
+
+#ifdef CONFIG_PERFMON
+ if ((task->thread.flags & IA64_THREAD_PM_VALID) != 0)
+ pfm_save_regs(task);
+
+ info = __get_cpu_var(pfm_syst_info);
+ if (info & PFM_CPUINFO_SYST_WIDE)
+ pfm_syst_wide_update_task(task, info, 0);
+#endif
+
+#ifdef CONFIG_IA32_SUPPORT
+ if (IS_IA32_PROCESS(ia64_task_regs(task)))
+ ia32_save_state(task);
+#endif
+}
+
+void
+ia64_load_extra (struct task_struct *task)
+{
+#ifdef CONFIG_PERFMON
+ unsigned long info;
+#endif
+
+ if ((task->thread.flags & IA64_THREAD_DBG_VALID) != 0)
+ ia64_load_debug_regs(&task->thread.dbr[0]);
+
+#ifdef CONFIG_PERFMON
+ if ((task->thread.flags & IA64_THREAD_PM_VALID) != 0)
+ pfm_load_regs(task);
+
+ info = __get_cpu_var(pfm_syst_info);
+ if (info & PFM_CPUINFO_SYST_WIDE)
+ pfm_syst_wide_update_task(task, info, 1);
+#endif
+
+#ifdef CONFIG_IA32_SUPPORT
+ if (IS_IA32_PROCESS(ia64_task_regs(task)))
+ ia32_load_state(task);
+#endif
+}
+
+/*
+ * Copy the state of an ia-64 thread.
+ *
+ * We get here through the following call chain:
+ *
+ * from user-level: from kernel:
+ *
+ * <clone syscall> <some kernel call frames>
+ * sys_clone :
+ * do_fork do_fork
+ * copy_thread copy_thread
+ *
+ * This means that the stack layout is as follows:
+ *
+ * +---------------------+ (highest addr)
+ * | struct pt_regs |
+ * +---------------------+
+ * | struct switch_stack |
+ * +---------------------+
+ * | |
+ * | memory stack |
+ * | | <-- sp (lowest addr)
+ * +---------------------+
+ *
+ * Observe that we copy the unat values that are in pt_regs and switch_stack. Spilling an
+ * integer to address X causes bit N in ar.unat to be set to the NaT bit of the register,
+ * with N=(X & 0x1ff)/8. Thus, copying the unat value preserves the NaT bits ONLY if the
+ * pt_regs structure in the parent is congruent to that of the child, modulo 512. Since
+ * the stack is page aligned and the page size is at least 4KB, this is always the case,
+ * so there is nothing to worry about.
+ */
+int
+copy_thread (int nr, unsigned long clone_flags,
+ unsigned long user_stack_base, unsigned long user_stack_size,
+ struct task_struct *p, struct pt_regs *regs)
+{
+ extern char ia64_ret_from_clone, ia32_ret_from_clone;
+ struct switch_stack *child_stack, *stack;
+ unsigned long rbs, child_rbs, rbs_size;
+ struct pt_regs *child_ptregs;
+ int retval = 0;
+
+#ifdef CONFIG_SMP
+ /*
+ * For SMP idle threads, fork_by_hand() calls do_fork with
+ * NULL regs.
+ */
+ if (!regs)
+ return 0;
+#endif
+
+ stack = ((struct switch_stack *) regs) - 1;
+
+ child_ptregs = (struct pt_regs *) ((unsigned long) p + IA64_STK_OFFSET) - 1;
+ child_stack = (struct switch_stack *) child_ptregs - 1;
+
+ /* copy parent's switch_stack & pt_regs to child: */
+ memcpy(child_stack, stack, sizeof(*child_ptregs) + sizeof(*child_stack));
+
+ rbs = (unsigned long) current + IA64_RBS_OFFSET;
+ child_rbs = (unsigned long) p + IA64_RBS_OFFSET;
+ rbs_size = stack->ar_bspstore - rbs;
+
+ /* copy the parent's register backing store to the child: */
+ memcpy((void *) child_rbs, (void *) rbs, rbs_size);
+
+ if (likely(user_mode(child_ptregs))) {
+ if ((clone_flags & CLONE_SETTLS) && !IS_IA32_PROCESS(regs))
+ child_ptregs->r13 = regs->r16; /* see sys_clone2() in entry.S */
+ if (user_stack_base) {
+ child_ptregs->r12 = user_stack_base + user_stack_size - 16;
+ child_ptregs->ar_bspstore = user_stack_base;
+ child_ptregs->ar_rnat = 0;
+ child_ptregs->loadrs = 0;
+ }
+ } else {
+ /*
+ * Note: we simply preserve the relative position of
+ * the stack pointer here. There is no need to
+ * allocate a scratch area here, since that will have
+ * been taken care of by the caller of sys_clone()
+ * already.
+ */
+ child_ptregs->r12 = (unsigned long) child_ptregs - 16; /* kernel sp */
+ child_ptregs->r13 = (unsigned long) p; /* set `current' pointer */
+ }
+ child_stack->ar_bspstore = child_rbs + rbs_size;
+ if (IS_IA32_PROCESS(regs))
+ child_stack->b0 = (unsigned long) &ia32_ret_from_clone;
+ else
+ child_stack->b0 = (unsigned long) &ia64_ret_from_clone;
+
+ /* copy parts of thread_struct: */
+ p->thread.ksp = (unsigned long) child_stack - 16;
+
+ /* stop some PSR bits from being inherited.
+ * the psr.up/psr.pp bits must be cleared on fork but inherited on execve()
+ * therefore we must specify them explicitly here and not include them in
+ * IA64_PSR_BITS_TO_CLEAR.
+ */
+ child_ptregs->cr_ipsr = ((child_ptregs->cr_ipsr | IA64_PSR_BITS_TO_SET)
+ & ~(IA64_PSR_BITS_TO_CLEAR | IA64_PSR_PP | IA64_PSR_UP));
+
+ /*
+ * NOTE: The calling convention considers all floating point
+ * registers in the high partition (fph) to be scratch. Since
+ * the only way to get to this point is through a system call,
+ * we know that the values in fph are all dead. Hence, there
+ * is no need to inherit the fph state from the parent to the
+ * child and all we have to do is to make sure that
+ * IA64_THREAD_FPH_VALID is cleared in the child.
+ *
+ * XXX We could push this optimization a bit further by
+ * clearing IA64_THREAD_FPH_VALID on ANY system call.
+ * However, it's not clear this is worth doing. Also, it
+ * would be a slight deviation from the normal Linux system
+ * call behavior where scratch registers are preserved across
+ * system calls (unless used by the system call itself).
+ */
+# define THREAD_FLAGS_TO_CLEAR (IA64_THREAD_FPH_VALID | IA64_THREAD_DBG_VALID \
+ | IA64_THREAD_PM_VALID)
+# define THREAD_FLAGS_TO_SET 0
+ p->thread.flags = ((current->thread.flags & ~THREAD_FLAGS_TO_CLEAR)
+ | THREAD_FLAGS_TO_SET);
+ ia64_drop_fpu(p); /* don't pick up stale state from a CPU's fph */
+#ifdef CONFIG_IA32_SUPPORT
+ /*
+ * If we're cloning an IA32 task then save the IA32 extra
+ * state from the current task to the new task
+ */
+ if (IS_IA32_PROCESS(ia64_task_regs(current))) {
+ ia32_save_state(p);
+ if (clone_flags & CLONE_SETTLS)
+ retval = ia32_clone_tls(p, child_ptregs);
+
+ /* Copy partially mapped page list */
+ if (!retval)
+ retval = ia32_copy_partial_page_list(p, clone_flags);
+ }
+#endif
+
+#ifdef CONFIG_PERFMON
+ if (current->thread.pfm_context)
+ pfm_inherit(p, child_ptregs);
+#endif
+ return retval;
+}
+
+static void
+do_copy_task_regs (struct task_struct *task, struct unw_frame_info *info, void *arg)
+{
+ unsigned long mask, sp, nat_bits = 0, ip, ar_rnat, urbs_end, cfm;
+ elf_greg_t *dst = arg;
+ struct pt_regs *pt;
+ char nat;
+ int i;
+
+ memset(dst, 0, sizeof(elf_gregset_t)); /* don't leak any kernel bits to user-level */
+
+ if (unw_unwind_to_user(info) < 0)
+ return;
+
+ unw_get_sp(info, &sp);
+ pt = (struct pt_regs *) (sp + 16);
+
+ urbs_end = ia64_get_user_rbs_end(task, pt, &cfm);
+
+ if (ia64_sync_user_rbs(task, info->sw, pt->ar_bspstore, urbs_end) < 0)
+ return;
+
+ ia64_peek(task, info->sw, urbs_end, (long) ia64_rse_rnat_addr((long *) urbs_end),
+ &ar_rnat);
+
+ /*
+ * coredump format:
+ * r0-r31
+ * NaT bits (for r0-r31; bit N == 1 iff rN is a NaT)
+ * predicate registers (p0-p63)
+ * b0-b7
+ * ip cfm user-mask
+ * ar.rsc ar.bsp ar.bspstore ar.rnat
+ * ar.ccv ar.unat ar.fpsr ar.pfs ar.lc ar.ec
+ */
+
+ /* r0 is zero */
+ for (i = 1, mask = (1UL << i); i < 32; ++i) {
+ unw_get_gr(info, i, &dst[i], &nat);
+ if (nat)
+ nat_bits |= mask;
+ mask <<= 1;
+ }
+ dst[32] = nat_bits;
+ unw_get_pr(info, &dst[33]);
+
+ for (i = 0; i < 8; ++i)
+ unw_get_br(info, i, &dst[34 + i]);
+
+ unw_get_rp(info, &ip);
+ dst[42] = ip + ia64_psr(pt)->ri;
+ dst[43] = cfm;
+ dst[44] = pt->cr_ipsr & IA64_PSR_UM;
+
+ unw_get_ar(info, UNW_AR_RSC, &dst[45]);
+ /*
+ * For bsp and bspstore, unw_get_ar() would return the kernel
+ * addresses, but we need the user-level addresses instead:
+ */
+ dst[46] = urbs_end; /* note: by convention PT_AR_BSP points to the end of the urbs! */
+ dst[47] = pt->ar_bspstore;
+ dst[48] = ar_rnat;
+ unw_get_ar(info, UNW_AR_CCV, &dst[49]);
+ unw_get_ar(info, UNW_AR_UNAT, &dst[50]);
+ unw_get_ar(info, UNW_AR_FPSR, &dst[51]);
+ dst[52] = pt->ar_pfs; /* UNW_AR_PFS is == to pt->cr_ifs for interrupt frames */
+ unw_get_ar(info, UNW_AR_LC, &dst[53]);
+ unw_get_ar(info, UNW_AR_EC, &dst[54]);
+ unw_get_ar(info, UNW_AR_CSD, &dst[55]);
+ unw_get_ar(info, UNW_AR_SSD, &dst[56]);
+}
+
+void
+do_dump_task_fpu (struct task_struct *task, struct unw_frame_info *info, void *arg)
+{
+ elf_fpreg_t *dst = arg;
+ int i;
+
+ memset(dst, 0, sizeof(elf_fpregset_t)); /* don't leak any "random" bits */
+
+ if (unw_unwind_to_user(info) < 0)
+ return;
+
+ /* f0 is 0.0, f1 is 1.0 */
+
+ for (i = 2; i < 32; ++i)
+ unw_get_fr(info, i, dst + i);
+
+ ia64_flush_fph(task);
+ if ((task->thread.flags & IA64_THREAD_FPH_VALID) != 0)
+ memcpy(dst + 32, task->thread.fph, 96*16);
+}
+
+void
+do_copy_regs (struct unw_frame_info *info, void *arg)
+{
+ do_copy_task_regs(current, info, arg);
+}
+
+void
+do_dump_fpu (struct unw_frame_info *info, void *arg)
+{
+ do_dump_task_fpu(current, info, arg);
+}
+
+int
+dump_task_regs(struct task_struct *task, elf_gregset_t *regs)
+{
+ struct unw_frame_info tcore_info;
+
+ if (current == task) {
+ unw_init_running(do_copy_regs, regs);
+ } else {
+ memset(&tcore_info, 0, sizeof(tcore_info));
+ unw_init_from_blocked_task(&tcore_info, task);
+ do_copy_task_regs(task, &tcore_info, regs);
+ }
+ return 1;
+}
+
+void
+ia64_elf_core_copy_regs (struct pt_regs *pt, elf_gregset_t dst)
+{
+ unw_init_running(do_copy_regs, dst);
+}
+
+int
+dump_task_fpu (struct task_struct *task, elf_fpregset_t *dst)
+{
+ struct unw_frame_info tcore_info;
+
+ if (current == task) {
+ unw_init_running(do_dump_fpu, dst);
+ } else {
+ memset(&tcore_info, 0, sizeof(tcore_info));
+ unw_init_from_blocked_task(&tcore_info, task);
+ do_dump_task_fpu(task, &tcore_info, dst);
+ }
+ return 1;
+}
+
+int
+dump_fpu (struct pt_regs *pt, elf_fpregset_t dst)
+{
+ unw_init_running(do_dump_fpu, dst);
+ return 1; /* f0-f31 are always valid so we always return 1 */
+}
+
+long
+sys_execve (char __user *filename, char __user * __user *argv, char __user * __user *envp,
+ struct pt_regs *regs)
+{
+ char *fname;
+ int error;
+
+ fname = getname(filename);
+ error = PTR_ERR(fname);
+ if (IS_ERR(fname))
+ goto out;
+ error = do_execve(fname, argv, envp, regs);
+ putname(fname);
+out:
+ return error;
+}
+
+pid_t
+kernel_thread (int (*fn)(void *), void *arg, unsigned long flags)
+{
+ extern void start_kernel_thread (void);
+ unsigned long *helper_fptr = (unsigned long *) &start_kernel_thread;
+ struct {
+ struct switch_stack sw;
+ struct pt_regs pt;
+ } regs;
+
+ memset(&regs, 0, sizeof(regs));
+ regs.pt.cr_iip = helper_fptr[0]; /* set entry point (IP) */
+ regs.pt.r1 = helper_fptr[1]; /* set GP */
+ regs.pt.r9 = (unsigned long) fn; /* 1st argument */
+ regs.pt.r11 = (unsigned long) arg; /* 2nd argument */
+ /* Preserve PSR bits, except for bits 32-34 and 37-45, which we can't read. */
+ regs.pt.cr_ipsr = ia64_getreg(_IA64_REG_PSR) | IA64_PSR_BN;
+ regs.pt.cr_ifs = 1UL << 63; /* mark as valid, empty frame */
+ regs.sw.ar_fpsr = regs.pt.ar_fpsr = ia64_getreg(_IA64_REG_AR_FPSR);
+ regs.sw.ar_bspstore = (unsigned long) current + IA64_RBS_OFFSET;
+ regs.sw.pr = (1 << PRED_KERNEL_STACK);
+ return do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0, &regs.pt, 0, NULL, NULL);
+}
+EXPORT_SYMBOL(kernel_thread);
+
+/* This gets called from kernel_thread() via ia64_invoke_thread_helper(). */
+int
+kernel_thread_helper (int (*fn)(void *), void *arg)
+{
+#ifdef CONFIG_IA32_SUPPORT
+ if (IS_IA32_PROCESS(ia64_task_regs(current))) {
+ /* A kernel thread is always a 64-bit process. */
+ current->thread.map_base = DEFAULT_MAP_BASE;
+ current->thread.task_size = DEFAULT_TASK_SIZE;
+ ia64_set_kr(IA64_KR_IO_BASE, current->thread.old_iob);
+ ia64_set_kr(IA64_KR_TSSD, current->thread.old_k1);
+ }
+#endif
+ return (*fn)(arg);
+}
+
+/*
+ * Flush thread state. This is called when a thread does an execve().
+ */
+void
+flush_thread (void)
+{
+ /* drop floating-point and debug-register state if it exists: */
+ current->thread.flags &= ~(IA64_THREAD_FPH_VALID | IA64_THREAD_DBG_VALID);
+ ia64_drop_fpu(current);
+ if (IS_IA32_PROCESS(ia64_task_regs(current)))
+ ia32_drop_partial_page_list(current);
+}
+
+/*
+ * Clean up state associated with current thread. This is called when
+ * the thread calls exit().
+ */
+void
+exit_thread (void)
+{
+ ia64_drop_fpu(current);
+#ifdef CONFIG_PERFMON
+ /* if needed, stop monitoring and flush state to perfmon context */
+ if (current->thread.pfm_context)
+ pfm_exit_thread(current);
+
+ /* free debug register resources */
+ if (current->thread.flags & IA64_THREAD_DBG_VALID)
+ pfm_release_debug_registers(current);
+#endif
+ if (IS_IA32_PROCESS(ia64_task_regs(current)))
+ ia32_drop_partial_page_list(current);
+}
+
+unsigned long
+get_wchan (struct task_struct *p)
+{
+ struct unw_frame_info info;
+ unsigned long ip;
+ int count = 0;
+
+ /*
+ * Note: p may not be a blocked task (it could be current or
+ * another process running on some other CPU. Rather than
+ * trying to determine if p is really blocked, we just assume
+ * it's blocked and rely on the unwind routines to fail
+ * gracefully if the process wasn't really blocked after all.
+ * --davidm 99/12/15
+ */
+ unw_init_from_blocked_task(&info, p);
+ do {
+ if (unw_unwind(&info) < 0)
+ return 0;
+ unw_get_ip(&info, &ip);
+ if (!in_sched_functions(ip))
+ return ip;
+ } while (count++ < 16);
+ return 0;
+}
+
+void
+cpu_halt (void)
+{
+ pal_power_mgmt_info_u_t power_info[8];
+ unsigned long min_power;
+ int i, min_power_state;
+
+ if (ia64_pal_halt_info(power_info) != 0)
+ return;
+
+ min_power_state = 0;
+ min_power = power_info[0].pal_power_mgmt_info_s.power_consumption;
+ for (i = 1; i < 8; ++i)
+ if (power_info[i].pal_power_mgmt_info_s.im
+ && power_info[i].pal_power_mgmt_info_s.power_consumption < min_power) {
+ min_power = power_info[i].pal_power_mgmt_info_s.power_consumption;
+ min_power_state = i;
+ }
+
+ while (1)
+ ia64_pal_halt(min_power_state);
+}
+
+void
+machine_restart (char *restart_cmd)
+{
+ (*efi.reset_system)(EFI_RESET_WARM, 0, 0, NULL);
+}
+
+EXPORT_SYMBOL(machine_restart);
+
+void
+machine_halt (void)
+{
+ cpu_halt();
+}
+
+EXPORT_SYMBOL(machine_halt);
+
+void
+machine_power_off (void)
+{
+ if (pm_power_off)
+ pm_power_off();
+ machine_halt();
+}
+
+EXPORT_SYMBOL(machine_power_off);