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/*
* Architecture-specific setup.
*
* Copyright (C) 1998-2001 Hewlett-Packard Co
* Copyright (C) 1998-2001 David Mosberger-Tang <davidm@hpl.hp.com>
*/
#define __KERNEL_SYSCALLS__ /* see <asm/unistd.h> */
#include <linux/config.h>
#include <linux/pm.h>
#include <linux/elf.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/smp_lock.h>
#include <linux/stddef.h>
#include <linux/unistd.h>
#include <asm/delay.h>
#include <asm/efi.h>
#include <asm/perfmon.h>
#include <asm/pgtable.h>
#include <asm/processor.h>
#include <asm/sal.h>
#include <asm/uaccess.h>
#include <asm/unwind.h>
#include <asm/user.h>
static void
do_show_stack (struct unw_frame_info *info, void *arg)
{
unsigned long ip, sp, bsp;
printk("\nCall Trace: ");
do {
unw_get_ip(info, &ip);
if (ip == 0)
break;
unw_get_sp(info, &sp);
unw_get_bsp(info, &bsp);
printk("[<%016lx>] sp=0x%016lx bsp=0x%016lx\n", ip, sp, bsp);
} while (unw_unwind(info) >= 0);
}
void
show_stack (struct task_struct *task)
{
if (!task)
unw_init_running(do_show_stack, 0);
else {
struct unw_frame_info info;
unw_init_from_blocked_task(&info, task);
do_show_stack(&info, 0);
}
}
void
show_regs (struct pt_regs *regs)
{
unsigned long ip = regs->cr_iip + ia64_psr(regs)->ri;
printk("\nPid: %d, comm: %20s\n", current->pid, current->comm);
printk("psr : %016lx ifs : %016lx ip : [<%016lx>] %s\n",
regs->cr_ipsr, regs->cr_ifs, ip, print_tainted());
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("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("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);
/* print the stacked registers if cr.ifs is valid: */
if (regs->cr_ifs & 0x8000000000000000) {
unsigned long val, sof, *bsp, ndirty;
int i, 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, ia64_rse_skip_regs(bsp, i));
printk("r%-3u:%c%016lx%s", 32 + i, is_nat ? '*' : ' ', val,
((i == sof - 1) || (i % 3) == 2) ? "\n" : " ");
}
}
if (!user_mode(regs))
show_stack(0);
}
void __attribute__((noreturn))
cpu_idle (void *unused)
{
/* endless idle loop with no priority at all */
init_idle();
current->nice = 20;
current->counter = -100;
while (1) {
#ifdef CONFIG_SMP
if (!current->need_resched)
min_xtp();
#endif
while (!current->need_resched)
continue;
#ifdef CONFIG_SMP
normal_xtp();
#endif
schedule();
check_pgt_cache();
if (pm_idle)
(*pm_idle)();
}
}
void
ia64_save_extra (struct task_struct *task)
{
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);
#endif
if (IS_IA32_PROCESS(ia64_task_regs(task)))
ia32_save_state(task);
}
void
ia64_load_extra (struct task_struct *task)
{
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);
#endif
if (IS_IA32_PROCESS(ia64_task_regs(task)))
ia32_load_state(task);
}
/*
* Copy the state of an ia-64 thread.
*
* We get here through the following call chain:
*
* <clone syscall>
* sys_clone
* do_fork
* copy_thread
*
* This means that the stack layout is as follows:
*
* +---------------------+ (highest addr)
* | struct pt_regs |
* +---------------------+
* | struct switch_stack |
* +---------------------+
* | |
* | memory stack |
* | | <-- sp (lowest addr)
* +---------------------+
*
* Note: if we get called through kernel_thread() then the memory
* above "(highest addr)" is valid kernel stack memory that needs to
* be copied as well.
*
* 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)
{
unsigned long rbs, child_rbs, rbs_size, stack_offset, stack_top, stack_used;
struct switch_stack *child_stack, *stack;
extern char ia64_ret_from_clone, ia32_ret_from_clone;
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_top = (unsigned long) current + IA64_STK_OFFSET;
stack = ((struct switch_stack *) regs) - 1;
stack_used = stack_top - (unsigned long) stack;
stack_offset = IA64_STK_OFFSET - stack_used;
child_stack = (struct switch_stack *) ((unsigned long) p + stack_offset);
child_ptregs = (struct pt_regs *) (child_stack + 1);
/* copy parent's switch_stack & pt_regs to child: */
memcpy(child_stack, stack, stack_used);
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 (user_mode(child_ptregs)) {
if (user_stack_base) {
child_ptregs->r12 = user_stack_base + user_stack_size;
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 + 1); /* kernel sp */
child_ptregs->r13 = (unsigned long) p; /* set `current' pointer */
}
if (IS_IA32_PROCESS(regs))
child_stack->b0 = (unsigned long) &ia32_ret_from_clone;
else
child_stack->b0 = (unsigned long) &ia64_ret_from_clone;
child_stack->ar_bspstore = child_rbs + rbs_size;
/* copy parts of thread_struct: */
p->thread.ksp = (unsigned long) child_stack - 16;
/*
* 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);
#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);
#endif
#ifdef CONFIG_PERFMON
if (p->thread.pfm_context)
retval = pfm_inherit(p, child_ptregs);
#endif
return retval;
}
void
do_copy_regs (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(current, pt, &cfm);
if (ia64_sync_user_rbs(current, info->sw, pt->ar_bspstore, urbs_end) < 0)
return;
ia64_peek(current, 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]);
}
void
do_dump_fpu (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(current);
if ((current->thread.flags & IA64_THREAD_FPH_VALID) != 0)
memcpy(dst + 32, current->thread.fph, 96*16);
}
void
ia64_elf_core_copy_regs (struct pt_regs *pt, elf_gregset_t dst)
{
unw_init_running(do_copy_regs, dst);
}
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 */
}
asmlinkage long
sys_execve (char *filename, char **argv, char **envp, struct pt_regs *regs)
{
int error;
filename = getname(filename);
error = PTR_ERR(filename);
if (IS_ERR(filename))
goto out;
error = do_execve(filename, argv, envp, regs);
putname(filename);
out:
return error;
}
pid_t
kernel_thread (int (*fn)(void *), void *arg, unsigned long flags)
{
struct task_struct *parent = current;
int result, tid;
tid = clone(flags | CLONE_VM, 0);
if (parent != current) {
result = (*fn)(arg);
_exit(result);
}
return tid;
}
/*
* 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);
#ifndef CONFIG_SMP
if (ia64_get_fpu_owner() == current)
ia64_set_fpu_owner(0);
#endif
}
#ifdef CONFIG_PERFMON
/*
* By the time we get here, the task is detached from the tasklist. This is important
* because it means that no other tasks can ever find it as a notifiied task, therfore
* there is no race condition between this code and let's say a pfm_context_create().
* Conversely, the pfm_cleanup_notifiers() cannot try to access a task's pfm context if
* this other task is in the middle of its own pfm_context_exit() because it would alreayd
* be out of the task list. Note that this case is very unlikely between a direct child
* and its parents (if it is the notified process) because of the way the exit is notified
* via SIGCHLD.
*/
void
release_thread (struct task_struct *task)
{
if (task->thread.pfm_context)
pfm_context_exit(task);
if (atomic_read(&task->thread.pfm_notifiers_check) > 0)
pfm_cleanup_notifiers(task);
}
#endif
/*
* Clean up state associated with current thread. This is called when
* the thread calls exit().
*/
void
exit_thread (void)
{
#ifndef CONFIG_SMP
if (ia64_get_fpu_owner() == current)
ia64_set_fpu_owner(0);
#endif
#ifdef CONFIG_PERFMON
/* stop monitoring */
if ((current->thread.flags & IA64_THREAD_PM_VALID) != 0) {
/*
* we cannot rely on switch_to() to save the PMU
* context for the last time. There is a possible race
* condition in SMP mode between the child and the
* parent. by explicitly saving the PMU context here
* we garantee no race. this call we also stop
* monitoring
*/
pfm_flush_regs(current);
/*
* make sure that switch_to() will not save context again
*/
current->thread.flags &= ~IA64_THREAD_PM_VALID;
}
#endif
}
unsigned long
get_wchan (struct task_struct *p)
{
struct unw_frame_info info;
unsigned long ip;
int count = 0;
/*
* These bracket the sleeping functions..
*/
extern void scheduling_functions_start_here(void);
extern void scheduling_functions_end_here(void);
# define first_sched ((unsigned long) scheduling_functions_start_here)
# define last_sched ((unsigned long) scheduling_functions_end_here)
/*
* 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 (ip < first_sched || ip >= last_sched)
return ip;
} while (count++ < 16);
return 0;
# undef first_sched
# undef last_sched
}
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, 0);
}
void
machine_halt (void)
{
cpu_halt();
}
void
machine_power_off (void)
{
if (pm_power_off)
pm_power_off();
machine_halt();
}
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