/*
* linux/arch/alpha/kernel/process.c
*
* Copyright (C) 1995 Linus Torvalds
*/
/*
* This file handles the architecture-dependent parts of process handling..
*/
#include <linux/config.h>
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/stddef.h>
#include <linux/unistd.h>
#include <linux/ptrace.h>
#include <linux/malloc.h>
#include <linux/ldt.h>
#include <linux/user.h>
#include <linux/a.out.h>
#include <linux/utsname.h>
#include <linux/time.h>
#include <linux/major.h>
#include <linux/stat.h>
#include <linux/mman.h>
#include <linux/elfcore.h>
#include <asm/reg.h>
#include <asm/segment.h>
#include <asm/system.h>
#include <asm/io.h>
asmlinkage int sys_sethae(unsigned long hae, unsigned long a1, unsigned long a2,
unsigned long a3, unsigned long a4, unsigned long a5,
struct pt_regs regs)
{
(®s)->hae = hae;
return 0;
}
asmlinkage int sys_idle(void)
{
if (current->pid != 0)
return -EPERM;
/* endless idle loop with no priority at all */
current->counter = -100;
for (;;) {
schedule();
}
}
void hard_reset_now(void)
{
#if defined(CONFIG_ALPHA_SRM) && defined(CONFIG_ALPHA_ALCOR)
/* who said DEC engineer's have no sense of humor? ;-)) */
*(int *) GRU_RESET = 0x0000dead;
mb();
#endif
halt();
}
void show_regs(struct pt_regs * regs)
{
printk("\nps: %04lx pc: [<%016lx>]\n", regs->ps, regs->pc);
printk("rp: [<%016lx>] sp: %p\n", regs->r26, regs+1);
printk(" r0: %016lx r1: %016lx r2: %016lx r3: %016lx\n",
regs->r0, regs->r1, regs->r2, regs->r3);
printk(" r4: %016lx r5: %016lx r6: %016lx r7: %016lx\n",
regs->r4, regs->r5, regs->r6, regs->r7);
printk(" r8: %016lx r16: %016lx r17: %016lx r18: %016lx\n",
regs->r8, regs->r16, regs->r17, regs->r18);
printk("r19: %016lx r20: %016lx r21: %016lx r22: %016lx\n",
regs->r19, regs->r20, regs->r21, regs->r22);
printk("r23: %016lx r24: %016lx r25: %016lx r26: %016lx\n",
regs->r23, regs->r24, regs->r25, regs->r26);
printk("r27: %016lx r28: %016lx r29: %016lx hae: %016lx\n",
regs->r27, regs->r28, regs->gp, regs->hae);
}
/*
* Re-start a thread when doing execve()
*/
void start_thread(struct pt_regs * regs, unsigned long pc, unsigned long sp)
{
set_fs(USER_DS);
regs->pc = pc;
regs->ps = 8;
wrusp(sp);
}
/*
* Free current thread data structures etc..
*/
void exit_thread(void)
{
}
void flush_thread(void)
{
}
void release_thread(struct task_struct *dead_task)
{
}
/*
* "alpha_clone()".. By the time we get here, the
* non-volatile registers have also been saved on the
* stack. We do some ugly pointer stuff here.. (see
* also copy_thread)
*
* Notice that "fork()" is implemented in terms of clone,
* with parameters (SIGCHLD, 0).
*/
int alpha_clone(unsigned long clone_flags, unsigned long usp,
struct switch_stack * swstack)
{
if (!usp)
usp = rdusp();
return do_fork(clone_flags, usp, (struct pt_regs *) (swstack+1));
}
extern void ret_from_sys_call(void);
/*
* Copy an alpha thread..
*
* Note the "stack_offset" stuff: when returning to kernel mode, we need
* to have some extra stack-space for the kernel stack that still exists
* after the "ret_from_sys_call". When returning to user mode, we only
* want the space needed by the syscall stack frame (ie "struct pt_regs").
* Use the passed "regs" pointer to determine how much space we need
* for a kernel fork().
*/
void copy_thread(int nr, unsigned long clone_flags, unsigned long usp,
struct task_struct * p, struct pt_regs * regs)
{
struct pt_regs * childregs;
struct switch_stack * childstack, *stack;
unsigned long stack_offset;
stack_offset = PAGE_SIZE - sizeof(struct pt_regs);
if (!(regs->ps & 8))
stack_offset = (PAGE_SIZE-1) & (unsigned long) regs;
childregs = (struct pt_regs *) (p->kernel_stack_page + stack_offset);
*childregs = *regs;
childregs->r0 = 0;
childregs->r19 = 0;
childregs->r20 = 1; /* OSF/1 has some strange fork() semantics.. */
regs->r20 = 0;
stack = ((struct switch_stack *) regs) - 1;
childstack = ((struct switch_stack *) childregs) - 1;
*childstack = *stack;
childstack->r26 = (unsigned long) ret_from_sys_call;
p->tss.usp = usp;
p->tss.ksp = (unsigned long) childstack;
p->tss.pal_flags = 1; /* set FEN, clear everything else */
p->tss.flags = current->tss.flags;
p->mm->context = 0;
}
/*
* fill in the user structure for a core dump..
*/
void dump_thread(struct pt_regs * pt, struct user * dump)
{
/* switch stack follows right below pt_regs: */
struct switch_stack * sw = ((struct switch_stack *) pt) - 1;
dump->magic = CMAGIC;
dump->start_code = current->mm->start_code;
dump->start_data = current->mm->start_data;
dump->start_stack = rdusp() & ~(PAGE_SIZE - 1);
dump->u_tsize = (current->mm->end_code - dump->start_code) >> PAGE_SHIFT;
dump->u_dsize = (current->mm->brk + (PAGE_SIZE - 1) - dump->start_data) >> PAGE_SHIFT;
dump->u_ssize =
(current->mm->start_stack - dump->start_stack + PAGE_SIZE - 1) >> PAGE_SHIFT;
/*
* We store the registers in an order/format that is
* compatible with DEC Unix/OSF/1 as this makes life easier
* for gdb.
*/
dump->regs[EF_V0] = pt->r0;
dump->regs[EF_T0] = pt->r1;
dump->regs[EF_T1] = pt->r2;
dump->regs[EF_T2] = pt->r3;
dump->regs[EF_T3] = pt->r4;
dump->regs[EF_T4] = pt->r5;
dump->regs[EF_T5] = pt->r6;
dump->regs[EF_T6] = pt->r7;
dump->regs[EF_T7] = pt->r8;
dump->regs[EF_S0] = sw->r9;
dump->regs[EF_S1] = sw->r10;
dump->regs[EF_S2] = sw->r11;
dump->regs[EF_S3] = sw->r12;
dump->regs[EF_S4] = sw->r13;
dump->regs[EF_S5] = sw->r14;
dump->regs[EF_S6] = sw->r15;
dump->regs[EF_A3] = pt->r19;
dump->regs[EF_A4] = pt->r20;
dump->regs[EF_A5] = pt->r21;
dump->regs[EF_T8] = pt->r22;
dump->regs[EF_T9] = pt->r23;
dump->regs[EF_T10] = pt->r24;
dump->regs[EF_T11] = pt->r25;
dump->regs[EF_RA] = pt->r26;
dump->regs[EF_T12] = pt->r27;
dump->regs[EF_AT] = pt->r28;
dump->regs[EF_SP] = rdusp();
dump->regs[EF_PS] = pt->ps;
dump->regs[EF_PC] = pt->pc;
dump->regs[EF_GP] = pt->gp;
dump->regs[EF_A0] = pt->r16;
dump->regs[EF_A1] = pt->r17;
dump->regs[EF_A2] = pt->r18;
memcpy((char *)dump->regs + EF_SIZE, sw->fp, 32 * 8);
}
int dump_fpu (struct pt_regs * regs, elf_fpregset_t *r)
{
/* switch stack follows right below pt_regs: */
struct switch_stack * sw = ((struct switch_stack *) regs) - 1;
memcpy(r, sw->fp, 32 * 8);
return 1;
}
/*
* sys_execve() executes a new program.
*
* This works due to the alpha calling sequence: the first 6 args
* are gotten from registers, while the rest is on the stack, so
* we get a0-a5 for free, and then magically find "struct pt_regs"
* on the stack for us..
*
* Don't do this at home.
*/
asmlinkage int sys_execve(unsigned long a0, unsigned long a1, unsigned long a2,
unsigned long a3, unsigned long a4, unsigned long a5,
struct pt_regs regs)
{
int error;
char * filename;
error = getname((char *) a0, &filename);
if (error)
return error;
error = do_execve(filename, (char **) a1, (char **) a2, ®s);
putname(filename);
return error;
}
