Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /*---------------------------------------------------------------------------+ |
| 2 | | load_store.c | |
| 3 | | | |
| 4 | | This file contains most of the code to interpret the FPU instructions | |
| 5 | | which load and store from user memory. | |
| 6 | | | |
| 7 | | Copyright (C) 1992,1993,1994,1997 | |
| 8 | | W. Metzenthen, 22 Parker St, Ormond, Vic 3163, | |
| 9 | | Australia. E-mail billm@suburbia.net | |
| 10 | | | |
| 11 | | | |
| 12 | +---------------------------------------------------------------------------*/ |
| 13 | |
| 14 | /*---------------------------------------------------------------------------+ |
| 15 | | Note: | |
| 16 | | The file contains code which accesses user memory. | |
| 17 | | Emulator static data may change when user memory is accessed, due to | |
| 18 | | other processes using the emulator while swapping is in progress. | |
| 19 | +---------------------------------------------------------------------------*/ |
| 20 | |
| 21 | #include <asm/uaccess.h> |
| 22 | |
| 23 | #include "fpu_system.h" |
| 24 | #include "exception.h" |
| 25 | #include "fpu_emu.h" |
| 26 | #include "status_w.h" |
| 27 | #include "control_w.h" |
| 28 | |
| 29 | |
| 30 | #define _NONE_ 0 /* st0_ptr etc not needed */ |
| 31 | #define _REG0_ 1 /* Will be storing st(0) */ |
| 32 | #define _PUSH_ 3 /* Need to check for space to push onto stack */ |
| 33 | #define _null_ 4 /* Function illegal or not implemented */ |
| 34 | |
| 35 | #define pop_0() { FPU_settag0(TAG_Empty); top++; } |
| 36 | |
| 37 | |
| 38 | static u_char const type_table[32] = { |
| 39 | _PUSH_, _PUSH_, _PUSH_, _PUSH_, |
| 40 | _null_, _null_, _null_, _null_, |
| 41 | _REG0_, _REG0_, _REG0_, _REG0_, |
| 42 | _REG0_, _REG0_, _REG0_, _REG0_, |
| 43 | _NONE_, _null_, _NONE_, _PUSH_, |
| 44 | _NONE_, _PUSH_, _null_, _PUSH_, |
| 45 | _NONE_, _null_, _NONE_, _REG0_, |
| 46 | _NONE_, _REG0_, _NONE_, _REG0_ |
| 47 | }; |
| 48 | |
| 49 | u_char const data_sizes_16[32] = { |
| 50 | 4, 4, 8, 2, 0, 0, 0, 0, |
| 51 | 4, 4, 8, 2, 4, 4, 8, 2, |
| 52 | 14, 0, 94, 10, 2, 10, 0, 8, |
| 53 | 14, 0, 94, 10, 2, 10, 2, 8 |
| 54 | }; |
| 55 | |
| 56 | static u_char const data_sizes_32[32] = { |
| 57 | 4, 4, 8, 2, 0, 0, 0, 0, |
| 58 | 4, 4, 8, 2, 4, 4, 8, 2, |
| 59 | 28, 0,108, 10, 2, 10, 0, 8, |
| 60 | 28, 0,108, 10, 2, 10, 2, 8 |
| 61 | }; |
| 62 | |
| 63 | int FPU_load_store(u_char type, fpu_addr_modes addr_modes, |
| 64 | void __user *data_address) |
| 65 | { |
| 66 | FPU_REG loaded_data; |
| 67 | FPU_REG *st0_ptr; |
| 68 | u_char st0_tag = TAG_Empty; /* This is just to stop a gcc warning. */ |
| 69 | u_char loaded_tag; |
| 70 | |
| 71 | st0_ptr = NULL; /* Initialized just to stop compiler warnings. */ |
| 72 | |
| 73 | if ( addr_modes.default_mode & PROTECTED ) |
| 74 | { |
| 75 | if ( addr_modes.default_mode == SEG32 ) |
| 76 | { |
| 77 | if ( access_limit < data_sizes_32[type] ) |
| 78 | math_abort(FPU_info,SIGSEGV); |
| 79 | } |
| 80 | else if ( addr_modes.default_mode == PM16 ) |
| 81 | { |
| 82 | if ( access_limit < data_sizes_16[type] ) |
| 83 | math_abort(FPU_info,SIGSEGV); |
| 84 | } |
| 85 | #ifdef PARANOID |
| 86 | else |
| 87 | EXCEPTION(EX_INTERNAL|0x140); |
| 88 | #endif /* PARANOID */ |
| 89 | } |
| 90 | |
| 91 | switch ( type_table[type] ) |
| 92 | { |
| 93 | case _NONE_: |
| 94 | break; |
| 95 | case _REG0_: |
| 96 | st0_ptr = &st(0); /* Some of these instructions pop after |
| 97 | storing */ |
| 98 | st0_tag = FPU_gettag0(); |
| 99 | break; |
| 100 | case _PUSH_: |
| 101 | { |
| 102 | if ( FPU_gettagi(-1) != TAG_Empty ) |
| 103 | { FPU_stack_overflow(); return 0; } |
| 104 | top--; |
| 105 | st0_ptr = &st(0); |
| 106 | } |
| 107 | break; |
| 108 | case _null_: |
| 109 | FPU_illegal(); |
| 110 | return 0; |
| 111 | #ifdef PARANOID |
| 112 | default: |
| 113 | EXCEPTION(EX_INTERNAL|0x141); |
| 114 | return 0; |
| 115 | #endif /* PARANOID */ |
| 116 | } |
| 117 | |
| 118 | switch ( type ) |
| 119 | { |
| 120 | case 000: /* fld m32real */ |
| 121 | clear_C1(); |
| 122 | loaded_tag = FPU_load_single((float __user *)data_address, &loaded_data); |
| 123 | if ( (loaded_tag == TAG_Special) |
| 124 | && isNaN(&loaded_data) |
| 125 | && (real_1op_NaN(&loaded_data) < 0) ) |
| 126 | { |
| 127 | top++; |
| 128 | break; |
| 129 | } |
| 130 | FPU_copy_to_reg0(&loaded_data, loaded_tag); |
| 131 | break; |
| 132 | case 001: /* fild m32int */ |
| 133 | clear_C1(); |
| 134 | loaded_tag = FPU_load_int32((long __user *)data_address, &loaded_data); |
| 135 | FPU_copy_to_reg0(&loaded_data, loaded_tag); |
| 136 | break; |
| 137 | case 002: /* fld m64real */ |
| 138 | clear_C1(); |
| 139 | loaded_tag = FPU_load_double((double __user *)data_address, &loaded_data); |
| 140 | if ( (loaded_tag == TAG_Special) |
| 141 | && isNaN(&loaded_data) |
| 142 | && (real_1op_NaN(&loaded_data) < 0) ) |
| 143 | { |
| 144 | top++; |
| 145 | break; |
| 146 | } |
| 147 | FPU_copy_to_reg0(&loaded_data, loaded_tag); |
| 148 | break; |
| 149 | case 003: /* fild m16int */ |
| 150 | clear_C1(); |
| 151 | loaded_tag = FPU_load_int16((short __user *)data_address, &loaded_data); |
| 152 | FPU_copy_to_reg0(&loaded_data, loaded_tag); |
| 153 | break; |
| 154 | case 010: /* fst m32real */ |
| 155 | clear_C1(); |
| 156 | FPU_store_single(st0_ptr, st0_tag, (float __user *)data_address); |
| 157 | break; |
| 158 | case 011: /* fist m32int */ |
| 159 | clear_C1(); |
| 160 | FPU_store_int32(st0_ptr, st0_tag, (long __user *)data_address); |
| 161 | break; |
| 162 | case 012: /* fst m64real */ |
| 163 | clear_C1(); |
| 164 | FPU_store_double(st0_ptr, st0_tag, (double __user *)data_address); |
| 165 | break; |
| 166 | case 013: /* fist m16int */ |
| 167 | clear_C1(); |
| 168 | FPU_store_int16(st0_ptr, st0_tag, (short __user *)data_address); |
| 169 | break; |
| 170 | case 014: /* fstp m32real */ |
| 171 | clear_C1(); |
| 172 | if ( FPU_store_single(st0_ptr, st0_tag, (float __user *)data_address) ) |
| 173 | pop_0(); /* pop only if the number was actually stored |
| 174 | (see the 80486 manual p16-28) */ |
| 175 | break; |
| 176 | case 015: /* fistp m32int */ |
| 177 | clear_C1(); |
| 178 | if ( FPU_store_int32(st0_ptr, st0_tag, (long __user *)data_address) ) |
| 179 | pop_0(); /* pop only if the number was actually stored |
| 180 | (see the 80486 manual p16-28) */ |
| 181 | break; |
| 182 | case 016: /* fstp m64real */ |
| 183 | clear_C1(); |
| 184 | if ( FPU_store_double(st0_ptr, st0_tag, (double __user *)data_address) ) |
| 185 | pop_0(); /* pop only if the number was actually stored |
| 186 | (see the 80486 manual p16-28) */ |
| 187 | break; |
| 188 | case 017: /* fistp m16int */ |
| 189 | clear_C1(); |
| 190 | if ( FPU_store_int16(st0_ptr, st0_tag, (short __user *)data_address) ) |
| 191 | pop_0(); /* pop only if the number was actually stored |
| 192 | (see the 80486 manual p16-28) */ |
| 193 | break; |
| 194 | case 020: /* fldenv m14/28byte */ |
| 195 | fldenv(addr_modes, (u_char __user *)data_address); |
| 196 | /* Ensure that the values just loaded are not changed by |
| 197 | fix-up operations. */ |
| 198 | return 1; |
| 199 | case 022: /* frstor m94/108byte */ |
| 200 | frstor(addr_modes, (u_char __user *)data_address); |
| 201 | /* Ensure that the values just loaded are not changed by |
| 202 | fix-up operations. */ |
| 203 | return 1; |
| 204 | case 023: /* fbld m80dec */ |
| 205 | clear_C1(); |
| 206 | loaded_tag = FPU_load_bcd((u_char __user *)data_address); |
| 207 | FPU_settag0(loaded_tag); |
| 208 | break; |
| 209 | case 024: /* fldcw */ |
| 210 | RE_ENTRANT_CHECK_OFF; |
| 211 | FPU_access_ok(VERIFY_READ, data_address, 2); |
| 212 | FPU_get_user(control_word, (unsigned short __user *) data_address); |
| 213 | RE_ENTRANT_CHECK_ON; |
| 214 | if ( partial_status & ~control_word & CW_Exceptions ) |
| 215 | partial_status |= (SW_Summary | SW_Backward); |
| 216 | else |
| 217 | partial_status &= ~(SW_Summary | SW_Backward); |
| 218 | #ifdef PECULIAR_486 |
| 219 | control_word |= 0x40; /* An 80486 appears to always set this bit */ |
| 220 | #endif /* PECULIAR_486 */ |
| 221 | return 1; |
| 222 | case 025: /* fld m80real */ |
| 223 | clear_C1(); |
| 224 | loaded_tag = FPU_load_extended((long double __user *)data_address, 0); |
| 225 | FPU_settag0(loaded_tag); |
| 226 | break; |
| 227 | case 027: /* fild m64int */ |
| 228 | clear_C1(); |
| 229 | loaded_tag = FPU_load_int64((long long __user *)data_address); |
| 230 | FPU_settag0(loaded_tag); |
| 231 | break; |
| 232 | case 030: /* fstenv m14/28byte */ |
| 233 | fstenv(addr_modes, (u_char __user *)data_address); |
| 234 | return 1; |
| 235 | case 032: /* fsave */ |
| 236 | fsave(addr_modes, (u_char __user *)data_address); |
| 237 | return 1; |
| 238 | case 033: /* fbstp m80dec */ |
| 239 | clear_C1(); |
| 240 | if ( FPU_store_bcd(st0_ptr, st0_tag, (u_char __user *)data_address) ) |
| 241 | pop_0(); /* pop only if the number was actually stored |
| 242 | (see the 80486 manual p16-28) */ |
| 243 | break; |
| 244 | case 034: /* fstcw m16int */ |
| 245 | RE_ENTRANT_CHECK_OFF; |
| 246 | FPU_access_ok(VERIFY_WRITE,data_address,2); |
| 247 | FPU_put_user(control_word, (unsigned short __user *) data_address); |
| 248 | RE_ENTRANT_CHECK_ON; |
| 249 | return 1; |
| 250 | case 035: /* fstp m80real */ |
| 251 | clear_C1(); |
| 252 | if ( FPU_store_extended(st0_ptr, st0_tag, (long double __user *)data_address) ) |
| 253 | pop_0(); /* pop only if the number was actually stored |
| 254 | (see the 80486 manual p16-28) */ |
| 255 | break; |
| 256 | case 036: /* fstsw m2byte */ |
| 257 | RE_ENTRANT_CHECK_OFF; |
| 258 | FPU_access_ok(VERIFY_WRITE,data_address,2); |
| 259 | FPU_put_user(status_word(),(unsigned short __user *) data_address); |
| 260 | RE_ENTRANT_CHECK_ON; |
| 261 | return 1; |
| 262 | case 037: /* fistp m64int */ |
| 263 | clear_C1(); |
| 264 | if ( FPU_store_int64(st0_ptr, st0_tag, (long long __user *)data_address) ) |
| 265 | pop_0(); /* pop only if the number was actually stored |
| 266 | (see the 80486 manual p16-28) */ |
| 267 | break; |
| 268 | } |
| 269 | return 0; |
| 270 | } |