/* [<][>][^][v][top][bottom][index][help] */
/*---------------------------------------------------------------------------+
| fpu_system.h |
| |
| Copyright (C) 1992,1994,1997 |
| W. Metzenthen, 22 Parker St, Ormond, Vic 3163, |
| Australia. E-mail billm@suburbia.net |
| |
+---------------------------------------------------------------------------*/
#ifndef _FPU_SYSTEM_H
#define _FPU_SYSTEM_H
/* system dependent definitions */
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/mm.h>
/* This sets the pointer FPU_info to point to the argument part
of the stack frame of math_emulate() */
#define SETUP_DATA_AREA(arg) FPU_info = (struct info *) &arg
/* s is always from a cpu register, and the cpu does bounds checking
* during register load --> no further bounds checks needed */
#define LDT_DESCRIPTOR(s) (((struct desc_struct *)current->mm->context.ldt)[(s) >> 3])
#define SEG_D_SIZE(x) ((x).b & (3 << 21))
#define SEG_G_BIT(x) ((x).b & (1 << 23))
#define SEG_GRANULARITY(x) (((x).b & (1 << 23)) ? 4096 : 1)
#define SEG_286_MODE(x) ((x).b & ( 0xff000000 | 0xf0000 | (1 << 23)))
#define SEG_BASE_ADDR(s) (((s).b & 0xff000000) \
| (((s).b & 0xff) << 16) | ((s).a >> 16))
#define SEG_LIMIT(s) (((s).b & 0xff0000) | ((s).a & 0xffff))
#define SEG_EXECUTE_ONLY(s) (((s).b & ((1 << 11) | (1 << 9))) == (1 << 11))
#define SEG_WRITE_PERM(s) (((s).b & ((1 << 11) | (1 << 9))) == (1 << 9))
#define SEG_EXPAND_DOWN(s) (((s).b & ((1 << 11) | (1 << 10))) \
== (1 << 10))
#define I387 (current->thread.xstate)
#define FPU_info (I387->soft.info)
#define FPU_CS (*(unsigned short *) &(FPU_info->___cs))
#define FPU_SS (*(unsigned short *) &(FPU_info->___ss))
#define FPU_DS (*(unsigned short *) &(FPU_info->___ds))
#define FPU_EAX (FPU_info->___eax)
#define FPU_EFLAGS (FPU_info->___eflags)
#define FPU_EIP (FPU_info->___eip)
#define FPU_ORIG_EIP (FPU_info->___orig_eip)
#define FPU_lookahead (I387->soft.lookahead)
/* nz if ip_offset and cs_selector are not to be set for the current
instruction. */
#define no_ip_update (*(u_char *)&(I387->soft.no_update))
#define FPU_rm (*(u_char *)&(I387->soft.rm))
/* Number of bytes of data which can be legally accessed by the current
instruction. This only needs to hold a number <= 108, so a byte will do. */
#define access_limit (*(u_char *)&(I387->soft.alimit))
#define partial_status (I387->soft.swd)
#define control_word (I387->soft.cwd)
#define fpu_tag_word (I387->soft.twd)
#define registers (I387->soft.st_space)
#define top (I387->soft.ftop)
#define instruction_address (*(struct address *)&I387->soft.fip)
#define operand_address (*(struct address *)&I387->soft.foo)
#define FPU_access_ok(x,y,z) if ( !access_ok(x,y,z) ) \
math_abort(FPU_info,SIGSEGV)
#define FPU_abort math_abort(FPU_info, SIGSEGV)
#undef FPU_IGNORE_CODE_SEGV
#ifdef FPU_IGNORE_CODE_SEGV
/* access_ok() is very expensive, and causes the emulator to run
about 20% slower if applied to the code. Anyway, errors due to bad
code addresses should be much rarer than errors due to bad data
addresses. */
#define FPU_code_access_ok(z)
#else
/* A simpler test than access_ok() can probably be done for
FPU_code_access_ok() because the only possible error is to step
past the upper boundary of a legal code area. */
#define FPU_code_access_ok(z) FPU_access_ok(VERIFY_READ,(void __user *)FPU_EIP,z)
#endif
#define FPU_get_user(x,y) get_user((x),(y))
#define FPU_put_user(x,y) put_user((x),(y))
#endif