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-rw-r--r--arch/i386/math-emu/fpu_system.h89
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diff --git a/arch/i386/math-emu/fpu_system.h b/arch/i386/math-emu/fpu_system.h
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+++ b/arch/i386/math-emu/fpu_system.h
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+/*---------------------------------------------------------------------------+
+ | 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.i387)
+#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)
+
+#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