2f892aca91
There seems to have been a broken assumption in the fpu context restoring code. It restores the context of the running process, without guarantee that the current process is the one that will be scheduled. This caused fpu saving for a different process to be triggered without fpu hardware being enabled, causing an fpu exception in the kernel. This practically only shows up with DEBUG_RACE on. Fix my thruby+me. The fix . is to only set the fpu-in-use-by-this-process flag in the exception handler, and then take care of fpu restoring when actually returning to userspace And the patch . translates fpu saving and restoring to c in arch_system.c, getting rid of a juicy chunk of assembly . makes osfxsr_feature private to arch_system.c . removes most of the arch dependent code from do_sigsend
893 lines
22 KiB
ArmAsm
893 lines
22 KiB
ArmAsm
/* sections */
|
|
|
|
|
|
#include <minix/config.h>
|
|
#include <minix/const.h>
|
|
#include <machine/interrupt.h>
|
|
#include "archconst.h"
|
|
#include "kernel/const.h"
|
|
#include "sconst.h"
|
|
|
|
/*
|
|
* This file contains a number of assembly code utility routines needed by the
|
|
* kernel. They are:
|
|
*/
|
|
|
|
.globl _monitor/* exit Minix and return to the monitor */
|
|
.globl _int86 /* let the monitor make an 8086 interrupt call */
|
|
#ifdef __ACK__
|
|
.globl _exit /* dummy for library routines */
|
|
.globl __exit /* dummy for library routines */
|
|
.globl ___exit /* dummy for library routines */
|
|
#endif
|
|
.globl ___main /* dummy for GCC */
|
|
.globl _phys_insw /* transfer data from (disk controller) port to memory */
|
|
.globl _phys_insb /* likewise byte by byte */
|
|
.globl _phys_outsw /* transfer data from memory to (disk controller) port */
|
|
.globl _phys_outsb /* likewise byte by byte */
|
|
.globl _phys_copy /* copy data from anywhere to anywhere in memory */
|
|
.globl _phys_copy_fault /* phys_copy pagefault */
|
|
.globl _phys_copy_fault_in_kernel /* phys_copy pagefault in kernel */
|
|
.globl _phys_memset /* write pattern anywhere in memory */
|
|
.globl _mem_rdw /* copy one word from [segment:offset] */
|
|
.globl _reset /* reset the system */
|
|
.globl _halt_cpu/* halts the current cpu when idle */
|
|
.globl _read_cpu_flags /* read the cpu flags */
|
|
.globl _read_cr0 /* read cr0 */
|
|
.globl _read_cr2 /* read cr2 */
|
|
.globl _getcr3val
|
|
.globl _write_cr0 /* write a value in cr0 */
|
|
.globl _read_cr3
|
|
.globl _read_cr4
|
|
.globl _write_cr4
|
|
|
|
.globl _catch_pagefaults
|
|
.globl _read_ds
|
|
.globl _read_cs
|
|
.globl _read_ss
|
|
.globl _idt_reload /* reload idt when returning to monitor. */
|
|
|
|
.globl _fninit /* non-waiting FPU initialization */
|
|
.globl _fnstsw /* store status word (non-waiting) */
|
|
.globl _fnstcw /* store control word (non-waiting) */
|
|
.globl _fxsave
|
|
.globl _fnsave
|
|
.globl _fxrstor
|
|
.globl _frstor
|
|
.globl _clts
|
|
|
|
/*
|
|
* The routines only guarantee to preserve the registers the C compiler
|
|
* expects to be preserved (ebx, esi, edi, ebp, esp, segment registers, and
|
|
* direction bit in the flags).
|
|
*/
|
|
|
|
.text
|
|
/*===========================================================================*/
|
|
/* monitor */
|
|
/*===========================================================================*/
|
|
/* PUBLIC void monitor(); */
|
|
/* Return to the monitor. */
|
|
|
|
_monitor:
|
|
movl _mon_sp, %esp /* restore monitor stack pointer */
|
|
movw $SS_SELECTOR, %dx /* monitor data segment */
|
|
mov %dx, %ds
|
|
mov %dx, %es
|
|
mov %dx, %fs
|
|
mov %dx, %gs
|
|
mov %dx, %ss
|
|
pop %edi
|
|
pop %esi
|
|
pop %ebp
|
|
lretw /* return to the monitor */
|
|
|
|
|
|
/*===========================================================================*/
|
|
/* int86 */
|
|
/*===========================================================================*/
|
|
/* PUBLIC void int86(); */
|
|
_int86:
|
|
cmpb $0, _mon_return /* is the monitor there? */
|
|
jne 0f
|
|
movb $0x01, %ah /* an int 13 error seems appropriate */
|
|
movb %ah, _reg86+0 /* reg86.w.f = 1 (set carry flag) */
|
|
movb %ah, _reg86+13 /* reg86.b.ah = 0x01 = "invalid command" */
|
|
ret
|
|
0:
|
|
push %ebp /* save C registers */
|
|
push %esi
|
|
push %edi
|
|
push %ebx
|
|
pushf /* save flags */
|
|
cli /* no interruptions */
|
|
|
|
inb $INT2_CTLMASK
|
|
movb %al, %ah
|
|
inb $INT_CTLMASK
|
|
push %eax /* save interrupt masks */
|
|
movl _irq_use, %eax /* map of in-use IRQ's */
|
|
and $~(1<<CLOCK_IRQ), %eax /* keep the clock ticking */
|
|
outb $INT_CTLMASK /* enable all unused IRQ's and vv. */
|
|
movb %ah, %al
|
|
outb $INT2_CTLMASK
|
|
|
|
mov $SS_SELECTOR, %eax /* monitor data segment */
|
|
mov %ax, %ss
|
|
xchgl _mon_sp, %esp /* switch stacks */
|
|
push _reg86+36 /* parameters used in INT call */
|
|
push _reg86+32
|
|
push _reg86+28
|
|
push _reg86+24
|
|
push _reg86+20
|
|
push _reg86+16
|
|
push _reg86+12
|
|
push _reg86+8
|
|
push _reg86+4
|
|
push _reg86+0
|
|
mov %ax, %ds /* remaining data selectors */
|
|
mov %ax, %es
|
|
mov %ax, %fs
|
|
mov %ax, %gs
|
|
push %cs
|
|
push $return /* kernel return address and selector */
|
|
ljmpw *20+2*4+10*4+2*4(%esp)
|
|
return:
|
|
pop _reg86+0
|
|
pop _reg86+4
|
|
pop _reg86+8
|
|
pop _reg86+12
|
|
pop _reg86+16
|
|
pop _reg86+20
|
|
pop _reg86+24
|
|
pop _reg86+28
|
|
pop _reg86+32
|
|
pop _reg86+36
|
|
lgdt _gdt+GDT_SELECTOR /* reload global descriptor table */
|
|
ljmp $CS_SELECTOR, $csinit
|
|
csinit:
|
|
mov $DS_SELECTOR, %eax
|
|
mov %ax, %ds
|
|
mov %ax, %es
|
|
mov %ax, %fs
|
|
mov %ax, %gs
|
|
mov %ax, %ss
|
|
xchgl _mon_sp, %esp /* unswitch stacks */
|
|
lidt _gdt+IDT_SELECTOR /* reload interrupt descriptor table */
|
|
|
|
#ifdef CONFIG_APIC
|
|
cmpl $0x0, lapic_addr
|
|
jne 3f
|
|
mov $0, %ebx
|
|
jmp 4f
|
|
|
|
3:
|
|
mov $FLAT_DS_SELECTOR, %ebx
|
|
mov %bx, %fs
|
|
movl lapic_addr, %eax
|
|
add $0x20, %eax
|
|
.byte 0x64; mov (%eax), %ebx
|
|
and $0xFF000000, %ebx
|
|
shr $24, %ebx
|
|
movzb %bl, %ebx
|
|
|
|
4:
|
|
add $apicid2cpuid, %ebx
|
|
movzb (%ebx), %eax
|
|
shl $3, %eax
|
|
mov %eax, %ebx
|
|
add $TSS_SELECTOR, %eax
|
|
addl _gdt+DESC_ACCESS, %eax
|
|
and $~0x02, %eax
|
|
ltr %bx /* set TSS register */
|
|
|
|
mov $DS_SELECTOR, %eax
|
|
mov %ax, %fs
|
|
|
|
#endif /* CONFIG_APIC */
|
|
|
|
pop %eax
|
|
outb $INT_CTLMASK /* restore interrupt masks */
|
|
movb %ah, %al
|
|
outb $INT2_CTLMASK
|
|
|
|
6:
|
|
addl %ecx, _lost_ticks /* record lost clock ticks */
|
|
|
|
popf /* restore flags */
|
|
pop %ebx /* restore C registers */
|
|
pop %edi
|
|
pop %esi
|
|
pop %ebp
|
|
ret
|
|
|
|
/*===========================================================================*/
|
|
/* exit */
|
|
/*===========================================================================*/
|
|
/*
|
|
* PUBLIC void exit();
|
|
* Some library routines use exit, so provide a dummy version.
|
|
* Actual calls to exit cannot occur in the kernel.
|
|
* GNU CC likes to call ___main from main() for nonobvious reasons.
|
|
*/
|
|
#ifdef __ACK__
|
|
_exit:
|
|
__exit:
|
|
___exit:
|
|
sti
|
|
jmp ___exit
|
|
#endif
|
|
|
|
___main:
|
|
ret
|
|
|
|
|
|
/*===========================================================================*/
|
|
/* phys_insw */
|
|
/*===========================================================================*/
|
|
/*
|
|
* PUBLIC void phys_insw(Port_t port, phys_bytes buf, size_t count);
|
|
* Input an array from an I/O port. Absolute address version of insw().
|
|
*/
|
|
|
|
_phys_insw:
|
|
push %ebp
|
|
mov %esp, %ebp
|
|
cld
|
|
push %edi
|
|
push %es
|
|
|
|
mov $FLAT_DS_SELECTOR, %ecx
|
|
mov %cx, %es
|
|
mov 8(%ebp), %edx /* port to read from */
|
|
mov 12(%ebp), %edi /* destination addr */
|
|
mov 16(%ebp), %ecx /* byte count */
|
|
shr $1, %ecx /* word count */
|
|
rep insw /* input many words */
|
|
pop %es
|
|
pop %edi
|
|
pop %ebp
|
|
ret
|
|
|
|
|
|
/*===========================================================================*/
|
|
/* phys_insb */
|
|
/*===========================================================================*/
|
|
/*
|
|
* PUBLIC void phys_insb(Port_t port, phys_bytes buf, size_t count);
|
|
* Input an array from an I/O port. Absolute address version of insb().
|
|
*/
|
|
|
|
_phys_insb:
|
|
push %ebp
|
|
mov %esp, %ebp
|
|
cld
|
|
push %edi
|
|
push %es
|
|
|
|
mov $FLAT_DS_SELECTOR, %ecx
|
|
mov %cx, %es
|
|
mov 8(%ebp), %edx /* port to read from */
|
|
mov 12(%ebp), %edi /* destination addr */
|
|
mov 16(%ebp), %ecx /* byte count */
|
|
rep insb /* input many bytes */
|
|
pop %es
|
|
pop %edi
|
|
pop %ebp
|
|
ret
|
|
|
|
|
|
/*===========================================================================*/
|
|
/* phys_outsw */
|
|
/*===========================================================================*/
|
|
/*
|
|
* PUBLIC void phys_outsw(Port_t port, phys_bytes buf, size_t count);
|
|
* Output an array to an I/O port. Absolute address version of outsw().
|
|
*/
|
|
|
|
.balign 16
|
|
_phys_outsw:
|
|
push %ebp
|
|
mov %esp, %ebp
|
|
cld
|
|
push %esi
|
|
push %ds
|
|
|
|
mov $FLAT_DS_SELECTOR, %ecx
|
|
mov %cx, %ds
|
|
mov 8(%ebp), %edx /* port to write to */
|
|
mov 12(%ebp), %esi /* source addr */
|
|
mov 16(%ebp), %ecx /* byte count */
|
|
shr $1, %ecx /* word count */
|
|
rep outsw /* output many words */
|
|
pop %ds
|
|
pop %esi
|
|
pop %ebp
|
|
ret
|
|
|
|
|
|
/*===========================================================================*/
|
|
/* phys_outsb */
|
|
/*===========================================================================*/
|
|
/*
|
|
* PUBLIC void phys_outsb(Port_t port, phys_bytes buf, size_t count);
|
|
* Output an array to an I/O port. Absolute address version of outsb().
|
|
*/
|
|
|
|
.balign 16
|
|
_phys_outsb:
|
|
push %ebp
|
|
mov %esp, %ebp
|
|
cld
|
|
push %esi
|
|
push %ds
|
|
|
|
mov $FLAT_DS_SELECTOR, %ecx
|
|
mov %cx, %ds
|
|
mov 8(%ebp), %edx /* port to write to */
|
|
mov 12(%ebp), %esi /* source addr */
|
|
mov 16(%ebp), %ecx /* byte count */
|
|
rep outsb /* output many bytes */
|
|
pop %ds
|
|
pop %esi
|
|
pop %ebp
|
|
ret
|
|
|
|
|
|
/*===========================================================================*/
|
|
/* phys_copy */
|
|
/*===========================================================================*/
|
|
/*
|
|
* PUBLIC phys_bytes phys_copy(phys_bytes source, phys_bytes destination,
|
|
* phys_bytes bytecount);
|
|
* Copy a block of physical memory.
|
|
*/
|
|
|
|
PC_ARGS = 4+4+4+4 /* 4 + 4 + 4 */
|
|
/* es edi esi eip src dst len */
|
|
|
|
.balign 16
|
|
_phys_copy:
|
|
cld
|
|
push %esi
|
|
push %edi
|
|
push %es
|
|
|
|
mov $FLAT_DS_SELECTOR, %eax
|
|
mov %ax, %es
|
|
|
|
mov PC_ARGS(%esp), %esi
|
|
mov PC_ARGS+4(%esp), %edi
|
|
mov PC_ARGS+4+4(%esp), %eax
|
|
|
|
cmp $10, %eax /* avoid align overhead for small counts */
|
|
jb pc_small
|
|
mov %esi, %ecx /* align source, hope target is too */
|
|
neg %ecx
|
|
and $3, %ecx /* count for alignment */
|
|
sub %ecx, %eax
|
|
|
|
rep movsb %es:(%esi), %es:(%edi)
|
|
mov %eax, %ecx
|
|
shr $2, %ecx /* count of dwords */
|
|
|
|
rep movsl %es:(%esi), %es:(%edi)
|
|
and $3, %eax
|
|
pc_small:
|
|
xchg %eax, %ecx /* remainder */
|
|
|
|
rep movsb %es:(%esi), %es:(%edi)
|
|
|
|
mov $0, %eax /* 0 means: no fault */
|
|
_phys_copy_fault: /* kernel can send us here */
|
|
pop %es
|
|
pop %edi
|
|
pop %esi
|
|
ret
|
|
|
|
_phys_copy_fault_in_kernel: /* kernel can send us here */
|
|
pop %es
|
|
pop %edi
|
|
pop %esi
|
|
mov %cr2, %eax
|
|
ret
|
|
|
|
/*===========================================================================*/
|
|
/* copy_msg_from_user */
|
|
/*===========================================================================*/
|
|
/*
|
|
* int copy_msg_from_user(struct proc * p, message * user_mbuf, message * dst);
|
|
*
|
|
* Copies a message of 36 bytes from user process space to a kernel buffer. This
|
|
* function assumes that the process address space is installed (cr3 loaded) and
|
|
* the local descriptor table of this process is loaded too.
|
|
*
|
|
* The %gs segment register is used to access the userspace memory. We load the
|
|
* process' data segment in this register.
|
|
*
|
|
* This function from the callers point of view either succeeds or returns an
|
|
* error which gives the caller a chance to respond accordingly. In fact it
|
|
* either succeeds or if it generates a pagefault, general protection or other
|
|
* exception, the trap handler has to redirect the execution to
|
|
* __user_copy_msg_pointer_failure where the error is reported to the caller
|
|
* without resolving the pagefault. It is not kernel's problem to deal with
|
|
* wrong pointers from userspace and the caller should return an error to
|
|
* userspace as if wrong values or request were passed to the kernel
|
|
*/
|
|
|
|
.balign 16
|
|
.globl _copy_msg_from_user
|
|
_copy_msg_from_user:
|
|
push %gs
|
|
|
|
mov 8(%esp), %eax
|
|
movw DSREG(%eax), %gs
|
|
|
|
/* load the source pointer */
|
|
mov 12(%esp), %ecx
|
|
/* load the destination pointer */
|
|
mov 16(%esp), %edx
|
|
|
|
mov %gs:0*4(%ecx), %eax
|
|
mov %eax, 0*4(%edx)
|
|
mov %gs:1*4(%ecx), %eax
|
|
mov %eax, 1*4(%edx)
|
|
mov %gs:2*4(%ecx), %eax
|
|
mov %eax, 2*4(%edx)
|
|
mov %gs:3*4(%ecx), %eax
|
|
mov %eax, 3*4(%edx)
|
|
mov %gs:4*4(%ecx), %eax
|
|
mov %eax, 4*4(%edx)
|
|
mov %gs:5*4(%ecx), %eax
|
|
mov %eax, 5*4(%edx)
|
|
mov %gs:6*4(%ecx), %eax
|
|
mov %eax, 6*4(%edx)
|
|
mov %gs:7*4(%ecx), %eax
|
|
mov %eax, 7*4(%edx)
|
|
mov %gs:8*4(%ecx), %eax
|
|
mov %eax, 8*4(%edx)
|
|
|
|
.globl ___copy_msg_from_user_end
|
|
___copy_msg_from_user_end:
|
|
|
|
pop %gs
|
|
|
|
movl $0, %eax
|
|
ret
|
|
|
|
/*===========================================================================*/
|
|
/* copy_msg_to_user */
|
|
/*===========================================================================*/
|
|
/*
|
|
* void copy_msg_to_user(struct proc * p, message * src, message * user_mbuf);
|
|
*
|
|
* Copies a message of 36 bytes to user process space from a kernel buffer. This
|
|
* function assumes that the process address space is installed (cr3 loaded) and
|
|
* the local descriptor table of this process is loaded too.
|
|
*
|
|
* All the other copy_msg_from_user() comments apply here as well!
|
|
*/
|
|
|
|
.balign 16
|
|
.globl _copy_msg_to_user
|
|
_copy_msg_to_user:
|
|
push %gs
|
|
|
|
mov 8(%esp), %eax
|
|
movw DSREG(%eax), %gs
|
|
|
|
/* load the source pointer */
|
|
mov 12(%esp), %ecx
|
|
/* load the destination pointer */
|
|
mov 16(%esp), %edx
|
|
|
|
mov 0*4(%ecx), %eax
|
|
mov %eax, %gs:0*4(%edx)
|
|
mov 1*4(%ecx), %eax
|
|
mov %eax, %gs:1*4(%edx)
|
|
mov 2*4(%ecx), %eax
|
|
mov %eax, %gs:2*4(%edx)
|
|
mov 3*4(%ecx), %eax
|
|
mov %eax, %gs:3*4(%edx)
|
|
mov 4*4(%ecx), %eax
|
|
mov %eax, %gs:4*4(%edx)
|
|
mov 5*4(%ecx), %eax
|
|
mov %eax, %gs:5*4(%edx)
|
|
mov 6*4(%ecx), %eax
|
|
mov %eax, %gs:6*4(%edx)
|
|
mov 7*4(%ecx), %eax
|
|
mov %eax, %gs:7*4(%edx)
|
|
mov 8*4(%ecx), %eax
|
|
mov %eax, %gs:8*4(%edx)
|
|
|
|
.globl ___copy_msg_to_user_end
|
|
___copy_msg_to_user_end:
|
|
|
|
pop %gs
|
|
|
|
movl $0, %eax
|
|
ret
|
|
|
|
/*
|
|
* if a function from a selected set of copies from or to userspace fails, it is
|
|
* because of a wrong pointer supplied by the userspace. We have to clean up and
|
|
* and return -1 to indicated that something wrong has happend. The place it was
|
|
* called from has to handle this situation. The exception handler redirect us
|
|
* here to continue, clean up and report the error
|
|
*/
|
|
.balign 16
|
|
.globl ___user_copy_msg_pointer_failure
|
|
___user_copy_msg_pointer_failure:
|
|
pop %gs
|
|
|
|
movl $-1, %eax
|
|
ret
|
|
|
|
/*===========================================================================*/
|
|
/* phys_memset */
|
|
/*===========================================================================*/
|
|
/*
|
|
* PUBLIC void phys_memset(phys_bytes source, unsigned long pattern,
|
|
* phys_bytes bytecount);
|
|
* Fill a block of physical memory with pattern.
|
|
*/
|
|
|
|
.balign 16
|
|
_phys_memset:
|
|
push %ebp
|
|
mov %esp, %ebp
|
|
push %esi
|
|
push %ebx
|
|
push %ds
|
|
|
|
mov 8(%ebp), %esi
|
|
mov 16(%ebp), %eax
|
|
mov $FLAT_DS_SELECTOR, %ebx
|
|
mov %bx, %ds
|
|
mov 12(%ebp), %ebx
|
|
shr $2, %eax
|
|
fill_start:
|
|
mov %ebx, (%esi)
|
|
add $4, %esi
|
|
dec %eax
|
|
jne fill_start
|
|
/* Any remaining bytes? */
|
|
mov 16(%ebp), %eax
|
|
and $3, %eax
|
|
remain_fill:
|
|
cmp $0, %eax
|
|
je fill_done
|
|
movb 12(%ebp), %bl
|
|
movb %bl, (%esi)
|
|
add $1, %esi
|
|
inc %ebp
|
|
dec %eax
|
|
jmp remain_fill
|
|
fill_done:
|
|
pop %ds
|
|
pop %ebx
|
|
pop %esi
|
|
pop %ebp
|
|
ret
|
|
|
|
|
|
/*===========================================================================*/
|
|
/* mem_rdw */
|
|
/*===========================================================================*/
|
|
/*
|
|
* PUBLIC u16_t mem_rdw(U16_t segment, u16_t *offset);
|
|
* Load and return word at far pointer segment:offset.
|
|
*/
|
|
|
|
.balign 16
|
|
_mem_rdw:
|
|
mov %ds, %cx
|
|
mov 4(%esp), %ds
|
|
mov 4+4(%esp), %eax /* offset */
|
|
movzwl (%eax), %eax /* word to return */
|
|
mov %cx, %ds
|
|
ret
|
|
|
|
|
|
/*===========================================================================*/
|
|
/* reset */
|
|
/*===========================================================================*/
|
|
/*
|
|
* PUBLIC void reset();
|
|
* Reset the system by loading IDT with offset 0 and interrupting.
|
|
*/
|
|
|
|
_reset:
|
|
lidt idt_zero
|
|
int $3 /* anything goes, the 386 will not like it */
|
|
.data
|
|
idt_zero:
|
|
.long 0, 0
|
|
.text
|
|
|
|
|
|
/*===========================================================================*/
|
|
/* halt_cpu */
|
|
/*===========================================================================*/
|
|
/*
|
|
* PUBLIC void halt_cpu(void);
|
|
* reanables interrupts and puts the cpu in the halts state. Once an interrupt
|
|
* is handled the execution resumes by disabling interrupts and continues
|
|
*/
|
|
_halt_cpu:
|
|
sti
|
|
hlt /* interrupts enabled only after this instruction is executed! */
|
|
/*
|
|
* interrupt handlers make sure that the interrupts are disabled when we
|
|
* get here so we take only _one_ interrupt after halting the CPU
|
|
*/
|
|
ret
|
|
|
|
/*===========================================================================*/
|
|
/* read_flags */
|
|
/*===========================================================================*/
|
|
/*
|
|
* PUBLIC unsigned long read_cpu_flags(void);
|
|
* Read CPU status flags from C.
|
|
*/
|
|
.balign 16
|
|
_read_cpu_flags:
|
|
pushf
|
|
mov (%esp), %eax
|
|
add $4, %esp
|
|
ret
|
|
|
|
_read_ds:
|
|
mov $0, %eax
|
|
mov %ds, %ax
|
|
ret
|
|
|
|
_read_cs:
|
|
mov $0, %eax
|
|
mov %cs, %ax
|
|
ret
|
|
|
|
_read_ss:
|
|
mov $0, %eax
|
|
mov %ss, %ax
|
|
ret
|
|
|
|
|
|
/*===========================================================================*/
|
|
/* fpu_routines */
|
|
/*===========================================================================*/
|
|
_fninit:
|
|
fninit
|
|
ret
|
|
|
|
_clts:
|
|
clts
|
|
ret
|
|
|
|
_fnstsw:
|
|
xor %eax, %eax
|
|
|
|
/* DO NOT CHANGE THE OPERAND!!! gas2ack does not handle it yet */
|
|
fnstsw %ax
|
|
ret
|
|
|
|
_fnstcw:
|
|
push %eax
|
|
mov 8(%esp), %eax
|
|
|
|
/* DO NOT CHANGE THE OPERAND!!! gas2ack does not handle it yet */
|
|
fnstcw (%eax)
|
|
pop %eax
|
|
ret
|
|
|
|
/*===========================================================================*/
|
|
/* fxsave */
|
|
/*===========================================================================*/
|
|
_fxsave:
|
|
mov 4(%esp), %eax
|
|
fxsave (%eax) /* Do not change the operand! (gas2ack) */
|
|
ret
|
|
|
|
/*===========================================================================*/
|
|
/* fnsave */
|
|
/*===========================================================================*/
|
|
_fnsave:
|
|
mov 4(%esp), %eax
|
|
fnsave (%eax) /* Do not change the operand! (gas2ack) */
|
|
fwait /* required for compatibility with processors prior pentium */
|
|
ret
|
|
|
|
/*===========================================================================*/
|
|
/* fxrstor */
|
|
/*===========================================================================*/
|
|
_fxrstor:
|
|
mov 4(%esp), %eax
|
|
fxrstor (%eax) /* Do not change the operand! (gas2ack) */
|
|
ret
|
|
|
|
/*===========================================================================*/
|
|
/* frstor */
|
|
/*===========================================================================*/
|
|
_frstor:
|
|
mov 4(%esp), %eax
|
|
frstor (%eax) /* Do not change the operand! (gas2ack) */
|
|
ret
|
|
|
|
|
|
/*===========================================================================*/
|
|
/* read_cr0 */
|
|
/*===========================================================================*/
|
|
/* PUBLIC unsigned long read_cr0(void); */
|
|
_read_cr0:
|
|
push %ebp
|
|
mov %esp, %ebp
|
|
mov %cr0, %eax
|
|
pop %ebp
|
|
ret
|
|
|
|
/*===========================================================================*/
|
|
/* write_cr0 */
|
|
/*===========================================================================*/
|
|
/* PUBLIC void write_cr0(unsigned long value); */
|
|
_write_cr0:
|
|
push %ebp
|
|
mov %esp, %ebp
|
|
mov 8(%ebp), %eax
|
|
mov %eax, %cr0
|
|
jmp 0f /* A jump is required for some flags */
|
|
0:
|
|
pop %ebp
|
|
ret
|
|
|
|
/*===========================================================================*/
|
|
/* read_cr2 */
|
|
/*===========================================================================*/
|
|
/* PUBLIC reg_t read_cr2(void); */
|
|
_read_cr2:
|
|
mov %cr2, %eax
|
|
ret
|
|
|
|
/*===========================================================================*/
|
|
/* read_cr3 */
|
|
/*===========================================================================*/
|
|
/* PUBLIC unsigned long read_cr3(void); */
|
|
_read_cr3:
|
|
push %ebp
|
|
mov %esp, %ebp
|
|
|
|
/* DO NOT CHANGE THE OPERAND!!! gas2ack does not handle it yet */
|
|
mov %cr3, %eax
|
|
pop %ebp
|
|
ret
|
|
|
|
/*===========================================================================*/
|
|
/* read_cr4 */
|
|
/*===========================================================================*/
|
|
/* PUBLIC unsigned long read_cr4(void); */
|
|
_read_cr4:
|
|
push %ebp
|
|
mov %esp, %ebp
|
|
|
|
/* DO NOT CHANGE THE OPERAND!!! gas2ack does not handle it yet */
|
|
mov %cr4, %eax
|
|
pop %ebp
|
|
ret
|
|
|
|
/*===========================================================================*/
|
|
/* write_cr4 */
|
|
/*===========================================================================*/
|
|
/* PUBLIC void write_cr4(unsigned long value); */
|
|
_write_cr4:
|
|
push %ebp
|
|
mov %esp, %ebp
|
|
mov 8(%ebp), %eax
|
|
|
|
/* DO NOT CHANGE THE OPERAND!!! gas2ack does not handle it yet */
|
|
mov %eax, %cr4
|
|
jmp 0f
|
|
0:
|
|
pop %ebp
|
|
ret
|
|
/*===========================================================================*/
|
|
/* getcr3val */
|
|
/*===========================================================================*/
|
|
/* PUBLIC unsigned long getcr3val(void); */
|
|
_getcr3val:
|
|
mov %cr3, %eax
|
|
ret
|
|
|
|
/*
|
|
* Read the Model Specific Register (MSR) of IA32 architecture
|
|
*
|
|
* void ia32_msr_read(u32_t reg, u32_t * hi, u32_t * lo)
|
|
*/
|
|
.globl _ia32_msr_read
|
|
_ia32_msr_read:
|
|
push %ebp
|
|
mov %esp, %ebp
|
|
|
|
mov 8(%ebp), %ecx
|
|
rdmsr
|
|
mov 12(%ebp), %ecx
|
|
mov %edx, (%ecx)
|
|
mov 16(%ebp), %ecx
|
|
mov %eax, (%ecx)
|
|
|
|
pop %ebp
|
|
ret
|
|
|
|
/*
|
|
* Write the Model Specific Register (MSR) of IA32 architecture
|
|
*
|
|
* void ia32_msr_write(u32_t reg, u32_t hi, u32_t lo)
|
|
*/
|
|
.globl _ia32_msr_write
|
|
_ia32_msr_write:
|
|
push %ebp
|
|
mov %esp, %ebp
|
|
|
|
mov 12(%ebp), %edx
|
|
mov 16(%ebp), %eax
|
|
mov 8(%ebp), %ecx
|
|
wrmsr
|
|
|
|
pop %ebp
|
|
ret
|
|
|
|
/*===========================================================================*/
|
|
/* idt_reload */
|
|
/*===========================================================================*/
|
|
/* PUBLIC void idt_reload (void); */
|
|
.balign 16
|
|
_idt_reload:
|
|
lidt _gdt+IDT_SELECTOR /* reload interrupt descriptor table */
|
|
ret
|
|
|
|
/*
|
|
* void reload_segment_regs(void)
|
|
*/
|
|
|
|
#define RELOAD_SEG_REG(reg) \
|
|
mov reg, %ax ;\
|
|
mov %ax, reg ;
|
|
|
|
.globl _reload_ds
|
|
_reload_ds:
|
|
RELOAD_SEG_REG(%ds)
|
|
ret
|
|
|
|
/*===========================================================================*/
|
|
/* switch_address_space */
|
|
/*===========================================================================*/
|
|
/* PUBLIC void switch_address_space(struct proc *p)
|
|
*
|
|
* sets the %cr3 register to the supplied value if it is not already set to the
|
|
* same value in which case it would only result in an extra TLB flush which is
|
|
* not desirable
|
|
*/
|
|
.balign 16
|
|
.globl _switch_address_space
|
|
_switch_address_space:
|
|
|
|
/* read the process pointer */
|
|
mov 4(%esp), %edx
|
|
/* enable process' segment descriptors */
|
|
lldt P_LDT_SEL(%edx)
|
|
/* get the new cr3 value */
|
|
movl P_CR3(%edx), %eax
|
|
/* test if the new cr3 != NULL */
|
|
cmpl $0, %eax
|
|
je 0f
|
|
|
|
/*
|
|
* test if the cr3 is loaded with the current value to avoid unnecessary
|
|
* TLB flushes
|
|
*/
|
|
mov %cr3, %ecx
|
|
cmp %ecx, %eax
|
|
je 0f
|
|
mov %eax, %cr3
|
|
mov %edx, _ptproc
|
|
0:
|
|
ret
|
|
|