1 /*---------------------------------------------------------------------------+ 2 | fpu_system.h | 3 | | 4 | Copyright (C) 1992,1994,1997 | 5 | W. Metzenthen, 22 Parker St, Ormond, Vic 3163, | 6 | Australia. E-mail billm@suburbia.net | 7 | | 8 +---------------------------------------------------------------------------*/ 9 10 #ifndef _FPU_SYSTEM_H 11 #define _FPU_SYSTEM_H 12 13 /* system dependent definitions */ 14 15 #include <linux/sched.h> 16 #include <linux/kernel.h> 17 #include <linux/mm.h> 18 19 /* This sets the pointer FPU_info to point to the argument part 20 of the stack frame of math_emulate() */ 21 #define SETUP_DATA_AREA(arg) FPU_info = (struct info *) &arg 22 23 #define LDT_DESCRIPTOR(s) (((struct desc_struct *)current->mm->context.ldt)[(s) >> 3]) 24 #define SEG_D_SIZE(x) ((x).b & (3 << 21)) 25 #define SEG_G_BIT(x) ((x).b & (1 << 23)) 26 #define SEG_GRANULARITY(x) (((x).b & (1 << 23)) ? 4096 : 1) 27 #define SEG_286_MODE(x) ((x).b & ( 0xff000000 | 0xf0000 | (1 << 23))) 28 #define SEG_BASE_ADDR(s) (((s).b & 0xff000000) \ 29 | (((s).b & 0xff) << 16) | ((s).a >> 16)) 30 #define SEG_LIMIT(s) (((s).b & 0xff0000) | ((s).a & 0xffff)) 31 #define SEG_EXECUTE_ONLY(s) (((s).b & ((1 << 11) | (1 << 9))) == (1 << 11)) 32 #define SEG_WRITE_PERM(s) (((s).b & ((1 << 11) | (1 << 9))) == (1 << 9)) 33 #define SEG_EXPAND_DOWN(s) (((s).b & ((1 << 11) | (1 << 10))) \ 34 == (1 << 10)) 35 36 #define I387 (current->thread.i387) 37 #define FPU_info (I387.soft.info) 38 39 #define FPU_CS (*(unsigned short *) &(FPU_info->___cs)) 40 #define FPU_SS (*(unsigned short *) &(FPU_info->___ss)) 41 #define FPU_DS (*(unsigned short *) &(FPU_info->___ds)) 42 #define FPU_EAX (FPU_info->___eax) 43 #define FPU_EFLAGS (FPU_info->___eflags) 44 #define FPU_EIP (FPU_info->___eip) 45 #define FPU_ORIG_EIP (FPU_info->___orig_eip) 46 47 #define FPU_lookahead (I387.soft.lookahead) 48 49 /* nz if ip_offset and cs_selector are not to be set for the current 50 instruction. */ 51 #define no_ip_update (*(u_char *)&(I387.soft.no_update)) 52 #define FPU_rm (*(u_char *)&(I387.soft.rm)) 53 54 /* Number of bytes of data which can be legally accessed by the current 55 instruction. This only needs to hold a number <= 108, so a byte will do. */ 56 #define access_limit (*(u_char *)&(I387.soft.alimit)) 57 58 #define partial_status (I387.soft.swd) 59 #define control_word (I387.soft.cwd) 60 #define fpu_tag_word (I387.soft.twd) 61 #define registers (I387.soft.st_space) 62 #define top (I387.soft.ftop) 63 64 #define instruction_address (*(struct address *)&I387.soft.fip) 65 #define operand_address (*(struct address *)&I387.soft.foo) 66 67 #define FPU_verify_area(x,y,z) if ( verify_area(x,y,z) ) \ 68 math_abort(FPU_info,SIGSEGV) 69 70 #undef FPU_IGNORE_CODE_SEGV 71 #ifdef FPU_IGNORE_CODE_SEGV 72 /* verify_area() is very expensive, and causes the emulator to run 73 about 20% slower if applied to the code. Anyway, errors due to bad 74 code addresses should be much rarer than errors due to bad data 75 addresses. */ 76 #define FPU_code_verify_area(z) 77 #else 78 /* A simpler test than verify_area() can probably be done for 79 FPU_code_verify_area() because the only possible error is to step 80 past the upper boundary of a legal code area. */ 81 #define FPU_code_verify_area(z) FPU_verify_area(VERIFY_READ,(void *)FPU_EIP,z) 82 #endif 83 84 #define FPU_get_user(x,y) get_user((x),(y)) 85 #define FPU_put_user(x,y) put_user((x),(y)) 86 87 #endif 88