Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * linux/arch/arm26/lib/uaccess-user.S |
| 3 | * |
| 4 | * Copyright (C) 1995, 1996,1997,1998 Russell King |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify |
| 7 | * it under the terms of the GNU General Public License version 2 as |
| 8 | * published by the Free Software Foundation. |
| 9 | * |
| 10 | * Routines to block copy data to/from user memory |
| 11 | * These are highly optimised both for the 4k page size |
| 12 | * and for various alignments. |
| 13 | */ |
| 14 | #include <linux/linkage.h> |
| 15 | #include <asm/assembler.h> |
| 16 | #include <asm/errno.h> |
| 17 | #include <asm/page.h> |
| 18 | |
| 19 | .text |
| 20 | |
| 21 | //FIXME - surely this can be done in C not asm, removing the problem of keeping C and asm in sync? (this is a struct uaccess_t) |
| 22 | .globl uaccess_user |
| 23 | uaccess_user: |
| 24 | .word uaccess_user_put_byte |
| 25 | .word uaccess_user_get_byte |
| 26 | .word uaccess_user_put_half |
| 27 | .word uaccess_user_get_half |
| 28 | .word uaccess_user_put_word |
| 29 | .word uaccess_user_get_word |
| 30 | .word uaccess_user_put_dword |
| 31 | .word uaccess_user_copy_from_user |
| 32 | .word uaccess_user_copy_to_user |
| 33 | .word uaccess_user_clear_user |
| 34 | .word uaccess_user_strncpy_from_user |
| 35 | .word uaccess_user_strnlen_user |
| 36 | |
| 37 | |
| 38 | @ In : r0 = x, r1 = addr, r2 = error |
| 39 | @ Out: r2 = error |
| 40 | uaccess_user_put_byte: |
| 41 | stmfd sp!, {lr} |
| 42 | USER( strbt r0, [r1]) |
| 43 | ldmfd sp!, {pc}^ |
| 44 | |
| 45 | @ In : r0 = x, r1 = addr, r2 = error |
| 46 | @ Out: r2 = error |
| 47 | uaccess_user_put_half: |
| 48 | stmfd sp!, {lr} |
| 49 | USER( strbt r0, [r1], #1) |
| 50 | mov r0, r0, lsr #8 |
| 51 | USER( strbt r0, [r1]) |
| 52 | ldmfd sp!, {pc}^ |
| 53 | |
| 54 | @ In : r0 = x, r1 = addr, r2 = error |
| 55 | @ Out: r2 = error |
| 56 | uaccess_user_put_word: |
| 57 | stmfd sp!, {lr} |
| 58 | USER( strt r0, [r1]) |
| 59 | ldmfd sp!, {pc}^ |
| 60 | |
| 61 | @ In : r0 = x, r1 = addr, r2 = error |
| 62 | @ Out: r2 = error |
| 63 | uaccess_user_put_dword: |
| 64 | stmfd sp!, {lr} |
| 65 | USER( strt r0, [r1], #4) |
| 66 | USER( strt r0, [r1], #0) |
| 67 | ldmfd sp!, {pc}^ |
| 68 | |
| 69 | 9001: mov r2, #-EFAULT |
| 70 | ldmfd sp!, {pc}^ |
| 71 | |
| 72 | |
| 73 | @ In : r0 = addr, r1 = error |
| 74 | @ Out: r0 = x, r1 = error |
| 75 | uaccess_user_get_byte: |
| 76 | stmfd sp!, {lr} |
| 77 | USER( ldrbt r0, [r0]) |
| 78 | ldmfd sp!, {pc}^ |
| 79 | |
| 80 | @ In : r0 = addr, r1 = error |
| 81 | @ Out: r0 = x, r1 = error |
| 82 | uaccess_user_get_half: |
| 83 | stmfd sp!, {lr} |
| 84 | USER( ldrt r0, [r0]) |
| 85 | mov r0, r0, lsl #16 |
| 86 | mov r0, r0, lsr #16 |
| 87 | ldmfd sp!, {pc}^ |
| 88 | |
| 89 | @ In : r0 = addr, r1 = error |
| 90 | @ Out: r0 = x, r1 = error |
| 91 | uaccess_user_get_word: |
| 92 | stmfd sp!, {lr} |
| 93 | USER( ldrt r0, [r0]) |
| 94 | ldmfd sp!, {pc}^ |
| 95 | |
| 96 | 9001: mov r1, #-EFAULT |
| 97 | ldmfd sp!, {pc}^ |
| 98 | |
| 99 | /* Prototype: int uaccess_user_copy_to_user(void *to, const char *from, size_t n) |
| 100 | * Purpose : copy a block to user memory from kernel memory |
| 101 | * Params : to - user memory |
| 102 | * : from - kernel memory |
| 103 | * : n - number of bytes to copy |
| 104 | * Returns : Number of bytes NOT copied. |
| 105 | */ |
| 106 | |
| 107 | .c2u_dest_not_aligned: |
| 108 | rsb ip, ip, #4 |
| 109 | cmp ip, #2 |
| 110 | ldrb r3, [r1], #1 |
| 111 | USER( strbt r3, [r0], #1) @ May fault |
| 112 | ldrgeb r3, [r1], #1 |
| 113 | USER( strgebt r3, [r0], #1) @ May fault |
| 114 | ldrgtb r3, [r1], #1 |
| 115 | USER( strgtbt r3, [r0], #1) @ May fault |
| 116 | sub r2, r2, ip |
| 117 | b .c2u_dest_aligned |
| 118 | |
| 119 | ENTRY(uaccess_user_copy_to_user) |
| 120 | stmfd sp!, {r2, r4 - r7, lr} |
| 121 | cmp r2, #4 |
| 122 | blt .c2u_not_enough |
| 123 | ands ip, r0, #3 |
| 124 | bne .c2u_dest_not_aligned |
| 125 | .c2u_dest_aligned: |
| 126 | |
| 127 | ands ip, r1, #3 |
| 128 | bne .c2u_src_not_aligned |
| 129 | /* |
| 130 | * Seeing as there has to be at least 8 bytes to copy, we can |
| 131 | * copy one word, and force a user-mode page fault... |
| 132 | */ |
| 133 | |
| 134 | .c2u_0fupi: subs r2, r2, #4 |
| 135 | addmi ip, r2, #4 |
| 136 | bmi .c2u_0nowords |
| 137 | ldr r3, [r1], #4 |
| 138 | USER( strt r3, [r0], #4) @ May fault |
| 139 | mov ip, r0, lsl #32 - PAGE_SHIFT @ On each page, use a ld/st??t instruction |
| 140 | rsb ip, ip, #0 |
| 141 | movs ip, ip, lsr #32 - PAGE_SHIFT |
| 142 | beq .c2u_0fupi |
| 143 | /* |
| 144 | * ip = max no. of bytes to copy before needing another "strt" insn |
| 145 | */ |
| 146 | cmp r2, ip |
| 147 | movlt ip, r2 |
| 148 | sub r2, r2, ip |
| 149 | subs ip, ip, #32 |
| 150 | blt .c2u_0rem8lp |
| 151 | |
| 152 | .c2u_0cpy8lp: ldmia r1!, {r3 - r6} |
| 153 | stmia r0!, {r3 - r6} @ Shouldnt fault |
| 154 | ldmia r1!, {r3 - r6} |
| 155 | stmia r0!, {r3 - r6} @ Shouldnt fault |
| 156 | subs ip, ip, #32 |
| 157 | bpl .c2u_0cpy8lp |
| 158 | .c2u_0rem8lp: cmn ip, #16 |
| 159 | ldmgeia r1!, {r3 - r6} |
| 160 | stmgeia r0!, {r3 - r6} @ Shouldnt fault |
| 161 | tst ip, #8 |
| 162 | ldmneia r1!, {r3 - r4} |
| 163 | stmneia r0!, {r3 - r4} @ Shouldnt fault |
| 164 | tst ip, #4 |
| 165 | ldrne r3, [r1], #4 |
| 166 | strnet r3, [r0], #4 @ Shouldnt fault |
| 167 | ands ip, ip, #3 |
| 168 | beq .c2u_0fupi |
| 169 | .c2u_0nowords: teq ip, #0 |
| 170 | beq .c2u_finished |
| 171 | .c2u_nowords: cmp ip, #2 |
| 172 | ldrb r3, [r1], #1 |
| 173 | USER( strbt r3, [r0], #1) @ May fault |
| 174 | ldrgeb r3, [r1], #1 |
| 175 | USER( strgebt r3, [r0], #1) @ May fault |
| 176 | ldrgtb r3, [r1], #1 |
| 177 | USER( strgtbt r3, [r0], #1) @ May fault |
| 178 | b .c2u_finished |
| 179 | |
| 180 | .c2u_not_enough: |
| 181 | movs ip, r2 |
| 182 | bne .c2u_nowords |
| 183 | .c2u_finished: mov r0, #0 |
| 184 | LOADREGS(fd,sp!,{r2, r4 - r7, pc}) |
| 185 | |
| 186 | .c2u_src_not_aligned: |
| 187 | bic r1, r1, #3 |
| 188 | ldr r7, [r1], #4 |
| 189 | cmp ip, #2 |
| 190 | bgt .c2u_3fupi |
| 191 | beq .c2u_2fupi |
| 192 | .c2u_1fupi: subs r2, r2, #4 |
| 193 | addmi ip, r2, #4 |
| 194 | bmi .c2u_1nowords |
| 195 | mov r3, r7, pull #8 |
| 196 | ldr r7, [r1], #4 |
| 197 | orr r3, r3, r7, push #24 |
| 198 | USER( strt r3, [r0], #4) @ May fault |
| 199 | mov ip, r0, lsl #32 - PAGE_SHIFT |
| 200 | rsb ip, ip, #0 |
| 201 | movs ip, ip, lsr #32 - PAGE_SHIFT |
| 202 | beq .c2u_1fupi |
| 203 | cmp r2, ip |
| 204 | movlt ip, r2 |
| 205 | sub r2, r2, ip |
| 206 | subs ip, ip, #16 |
| 207 | blt .c2u_1rem8lp |
| 208 | |
| 209 | .c2u_1cpy8lp: mov r3, r7, pull #8 |
| 210 | ldmia r1!, {r4 - r7} |
| 211 | orr r3, r3, r4, push #24 |
| 212 | mov r4, r4, pull #8 |
| 213 | orr r4, r4, r5, push #24 |
| 214 | mov r5, r5, pull #8 |
| 215 | orr r5, r5, r6, push #24 |
| 216 | mov r6, r6, pull #8 |
| 217 | orr r6, r6, r7, push #24 |
| 218 | stmia r0!, {r3 - r6} @ Shouldnt fault |
| 219 | subs ip, ip, #16 |
| 220 | bpl .c2u_1cpy8lp |
| 221 | .c2u_1rem8lp: tst ip, #8 |
| 222 | movne r3, r7, pull #8 |
| 223 | ldmneia r1!, {r4, r7} |
| 224 | orrne r3, r3, r4, push #24 |
| 225 | movne r4, r4, pull #8 |
| 226 | orrne r4, r4, r7, push #24 |
| 227 | stmneia r0!, {r3 - r4} @ Shouldnt fault |
| 228 | tst ip, #4 |
| 229 | movne r3, r7, pull #8 |
| 230 | ldrne r7, [r1], #4 |
| 231 | orrne r3, r3, r7, push #24 |
| 232 | strnet r3, [r0], #4 @ Shouldnt fault |
| 233 | ands ip, ip, #3 |
| 234 | beq .c2u_1fupi |
| 235 | .c2u_1nowords: mov r3, r7, lsr #byte(1) |
| 236 | teq ip, #0 |
| 237 | beq .c2u_finished |
| 238 | cmp ip, #2 |
| 239 | USER( strbt r3, [r0], #1) @ May fault |
| 240 | movge r3, r7, lsr #byte(2) |
| 241 | USER( strgebt r3, [r0], #1) @ May fault |
| 242 | movgt r3, r7, lsr #byte(3) |
| 243 | USER( strgtbt r3, [r0], #1) @ May fault |
| 244 | b .c2u_finished |
| 245 | |
| 246 | .c2u_2fupi: subs r2, r2, #4 |
| 247 | addmi ip, r2, #4 |
| 248 | bmi .c2u_2nowords |
| 249 | mov r3, r7, pull #16 |
| 250 | ldr r7, [r1], #4 |
| 251 | orr r3, r3, r7, push #16 |
| 252 | USER( strt r3, [r0], #4) @ May fault |
| 253 | mov ip, r0, lsl #32 - PAGE_SHIFT |
| 254 | rsb ip, ip, #0 |
| 255 | movs ip, ip, lsr #32 - PAGE_SHIFT |
| 256 | beq .c2u_2fupi |
| 257 | cmp r2, ip |
| 258 | movlt ip, r2 |
| 259 | sub r2, r2, ip |
| 260 | subs ip, ip, #16 |
| 261 | blt .c2u_2rem8lp |
| 262 | |
| 263 | .c2u_2cpy8lp: mov r3, r7, pull #16 |
| 264 | ldmia r1!, {r4 - r7} |
| 265 | orr r3, r3, r4, push #16 |
| 266 | mov r4, r4, pull #16 |
| 267 | orr r4, r4, r5, push #16 |
| 268 | mov r5, r5, pull #16 |
| 269 | orr r5, r5, r6, push #16 |
| 270 | mov r6, r6, pull #16 |
| 271 | orr r6, r6, r7, push #16 |
| 272 | stmia r0!, {r3 - r6} @ Shouldnt fault |
| 273 | subs ip, ip, #16 |
| 274 | bpl .c2u_2cpy8lp |
| 275 | .c2u_2rem8lp: tst ip, #8 |
| 276 | movne r3, r7, pull #16 |
| 277 | ldmneia r1!, {r4, r7} |
| 278 | orrne r3, r3, r4, push #16 |
| 279 | movne r4, r4, pull #16 |
| 280 | orrne r4, r4, r7, push #16 |
| 281 | stmneia r0!, {r3 - r4} @ Shouldnt fault |
| 282 | tst ip, #4 |
| 283 | movne r3, r7, pull #16 |
| 284 | ldrne r7, [r1], #4 |
| 285 | orrne r3, r3, r7, push #16 |
| 286 | strnet r3, [r0], #4 @ Shouldnt fault |
| 287 | ands ip, ip, #3 |
| 288 | beq .c2u_2fupi |
| 289 | .c2u_2nowords: mov r3, r7, lsr #byte(2) |
| 290 | teq ip, #0 |
| 291 | beq .c2u_finished |
| 292 | cmp ip, #2 |
| 293 | USER( strbt r3, [r0], #1) @ May fault |
| 294 | movge r3, r7, lsr #byte(3) |
| 295 | USER( strgebt r3, [r0], #1) @ May fault |
| 296 | ldrgtb r3, [r1], #0 |
| 297 | USER( strgtbt r3, [r0], #1) @ May fault |
| 298 | b .c2u_finished |
| 299 | |
| 300 | .c2u_3fupi: subs r2, r2, #4 |
| 301 | addmi ip, r2, #4 |
| 302 | bmi .c2u_3nowords |
| 303 | mov r3, r7, pull #24 |
| 304 | ldr r7, [r1], #4 |
| 305 | orr r3, r3, r7, push #8 |
| 306 | USER( strt r3, [r0], #4) @ May fault |
| 307 | mov ip, r0, lsl #32 - PAGE_SHIFT |
| 308 | rsb ip, ip, #0 |
| 309 | movs ip, ip, lsr #32 - PAGE_SHIFT |
| 310 | beq .c2u_3fupi |
| 311 | cmp r2, ip |
| 312 | movlt ip, r2 |
| 313 | sub r2, r2, ip |
| 314 | subs ip, ip, #16 |
| 315 | blt .c2u_3rem8lp |
| 316 | |
| 317 | .c2u_3cpy8lp: mov r3, r7, pull #24 |
| 318 | ldmia r1!, {r4 - r7} |
| 319 | orr r3, r3, r4, push #8 |
| 320 | mov r4, r4, pull #24 |
| 321 | orr r4, r4, r5, push #8 |
| 322 | mov r5, r5, pull #24 |
| 323 | orr r5, r5, r6, push #8 |
| 324 | mov r6, r6, pull #24 |
| 325 | orr r6, r6, r7, push #8 |
| 326 | stmia r0!, {r3 - r6} @ Shouldnt fault |
| 327 | subs ip, ip, #16 |
| 328 | bpl .c2u_3cpy8lp |
| 329 | .c2u_3rem8lp: tst ip, #8 |
| 330 | movne r3, r7, pull #24 |
| 331 | ldmneia r1!, {r4, r7} |
| 332 | orrne r3, r3, r4, push #8 |
| 333 | movne r4, r4, pull #24 |
| 334 | orrne r4, r4, r7, push #8 |
| 335 | stmneia r0!, {r3 - r4} @ Shouldnt fault |
| 336 | tst ip, #4 |
| 337 | movne r3, r7, pull #24 |
| 338 | ldrne r7, [r1], #4 |
| 339 | orrne r3, r3, r7, push #8 |
| 340 | strnet r3, [r0], #4 @ Shouldnt fault |
| 341 | ands ip, ip, #3 |
| 342 | beq .c2u_3fupi |
| 343 | .c2u_3nowords: mov r3, r7, lsr #byte(3) |
| 344 | teq ip, #0 |
| 345 | beq .c2u_finished |
| 346 | cmp ip, #2 |
| 347 | USER( strbt r3, [r0], #1) @ May fault |
| 348 | ldrgeb r3, [r1], #1 |
| 349 | USER( strgebt r3, [r0], #1) @ May fault |
| 350 | ldrgtb r3, [r1], #0 |
| 351 | USER( strgtbt r3, [r0], #1) @ May fault |
| 352 | b .c2u_finished |
| 353 | |
| 354 | .section .fixup,"ax" |
| 355 | .align 0 |
| 356 | 9001: LOADREGS(fd,sp!, {r0, r4 - r7, pc}) |
| 357 | .previous |
| 358 | |
| 359 | /* Prototype: unsigned long uaccess_user_copy_from_user(void *to,const void *from,unsigned long n); |
| 360 | * Purpose : copy a block from user memory to kernel memory |
| 361 | * Params : to - kernel memory |
| 362 | * : from - user memory |
| 363 | * : n - number of bytes to copy |
| 364 | * Returns : Number of bytes NOT copied. |
| 365 | */ |
| 366 | .cfu_dest_not_aligned: |
| 367 | rsb ip, ip, #4 |
| 368 | cmp ip, #2 |
| 369 | USER( ldrbt r3, [r1], #1) @ May fault |
| 370 | strb r3, [r0], #1 |
| 371 | USER( ldrgebt r3, [r1], #1) @ May fault |
| 372 | strgeb r3, [r0], #1 |
| 373 | USER( ldrgtbt r3, [r1], #1) @ May fault |
| 374 | strgtb r3, [r0], #1 |
| 375 | sub r2, r2, ip |
| 376 | b .cfu_dest_aligned |
| 377 | |
| 378 | ENTRY(uaccess_user_copy_from_user) |
| 379 | stmfd sp!, {r0, r2, r4 - r7, lr} |
| 380 | cmp r2, #4 |
| 381 | blt .cfu_not_enough |
| 382 | ands ip, r0, #3 |
| 383 | bne .cfu_dest_not_aligned |
| 384 | .cfu_dest_aligned: |
| 385 | ands ip, r1, #3 |
| 386 | bne .cfu_src_not_aligned |
| 387 | /* |
| 388 | * Seeing as there has to be at least 8 bytes to copy, we can |
| 389 | * copy one word, and force a user-mode page fault... |
| 390 | */ |
| 391 | |
| 392 | .cfu_0fupi: subs r2, r2, #4 |
| 393 | addmi ip, r2, #4 |
| 394 | bmi .cfu_0nowords |
| 395 | USER( ldrt r3, [r1], #4) |
| 396 | str r3, [r0], #4 |
| 397 | mov ip, r1, lsl #32 - PAGE_SHIFT @ On each page, use a ld/st??t instruction |
| 398 | rsb ip, ip, #0 |
| 399 | movs ip, ip, lsr #32 - PAGE_SHIFT |
| 400 | beq .cfu_0fupi |
| 401 | /* |
| 402 | * ip = max no. of bytes to copy before needing another "strt" insn |
| 403 | */ |
| 404 | cmp r2, ip |
| 405 | movlt ip, r2 |
| 406 | sub r2, r2, ip |
| 407 | subs ip, ip, #32 |
| 408 | blt .cfu_0rem8lp |
| 409 | |
| 410 | .cfu_0cpy8lp: ldmia r1!, {r3 - r6} @ Shouldnt fault |
| 411 | stmia r0!, {r3 - r6} |
| 412 | ldmia r1!, {r3 - r6} @ Shouldnt fault |
| 413 | stmia r0!, {r3 - r6} |
| 414 | subs ip, ip, #32 |
| 415 | bpl .cfu_0cpy8lp |
| 416 | .cfu_0rem8lp: cmn ip, #16 |
| 417 | ldmgeia r1!, {r3 - r6} @ Shouldnt fault |
| 418 | stmgeia r0!, {r3 - r6} |
| 419 | tst ip, #8 |
| 420 | ldmneia r1!, {r3 - r4} @ Shouldnt fault |
| 421 | stmneia r0!, {r3 - r4} |
| 422 | tst ip, #4 |
| 423 | ldrnet r3, [r1], #4 @ Shouldnt fault |
| 424 | strne r3, [r0], #4 |
| 425 | ands ip, ip, #3 |
| 426 | beq .cfu_0fupi |
| 427 | .cfu_0nowords: teq ip, #0 |
| 428 | beq .cfu_finished |
| 429 | .cfu_nowords: cmp ip, #2 |
| 430 | USER( ldrbt r3, [r1], #1) @ May fault |
| 431 | strb r3, [r0], #1 |
| 432 | USER( ldrgebt r3, [r1], #1) @ May fault |
| 433 | strgeb r3, [r0], #1 |
| 434 | USER( ldrgtbt r3, [r1], #1) @ May fault |
| 435 | strgtb r3, [r0], #1 |
| 436 | b .cfu_finished |
| 437 | |
| 438 | .cfu_not_enough: |
| 439 | movs ip, r2 |
| 440 | bne .cfu_nowords |
| 441 | .cfu_finished: mov r0, #0 |
| 442 | add sp, sp, #8 |
| 443 | LOADREGS(fd,sp!,{r4 - r7, pc}) |
| 444 | |
| 445 | .cfu_src_not_aligned: |
| 446 | bic r1, r1, #3 |
| 447 | USER( ldrt r7, [r1], #4) @ May fault |
| 448 | cmp ip, #2 |
| 449 | bgt .cfu_3fupi |
| 450 | beq .cfu_2fupi |
| 451 | .cfu_1fupi: subs r2, r2, #4 |
| 452 | addmi ip, r2, #4 |
| 453 | bmi .cfu_1nowords |
| 454 | mov r3, r7, pull #8 |
| 455 | USER( ldrt r7, [r1], #4) @ May fault |
| 456 | orr r3, r3, r7, push #24 |
| 457 | str r3, [r0], #4 |
| 458 | mov ip, r1, lsl #32 - PAGE_SHIFT |
| 459 | rsb ip, ip, #0 |
| 460 | movs ip, ip, lsr #32 - PAGE_SHIFT |
| 461 | beq .cfu_1fupi |
| 462 | cmp r2, ip |
| 463 | movlt ip, r2 |
| 464 | sub r2, r2, ip |
| 465 | subs ip, ip, #16 |
| 466 | blt .cfu_1rem8lp |
| 467 | |
| 468 | .cfu_1cpy8lp: mov r3, r7, pull #8 |
| 469 | ldmia r1!, {r4 - r7} @ Shouldnt fault |
| 470 | orr r3, r3, r4, push #24 |
| 471 | mov r4, r4, pull #8 |
| 472 | orr r4, r4, r5, push #24 |
| 473 | mov r5, r5, pull #8 |
| 474 | orr r5, r5, r6, push #24 |
| 475 | mov r6, r6, pull #8 |
| 476 | orr r6, r6, r7, push #24 |
| 477 | stmia r0!, {r3 - r6} |
| 478 | subs ip, ip, #16 |
| 479 | bpl .cfu_1cpy8lp |
| 480 | .cfu_1rem8lp: tst ip, #8 |
| 481 | movne r3, r7, pull #8 |
| 482 | ldmneia r1!, {r4, r7} @ Shouldnt fault |
| 483 | orrne r3, r3, r4, push #24 |
| 484 | movne r4, r4, pull #8 |
| 485 | orrne r4, r4, r7, push #24 |
| 486 | stmneia r0!, {r3 - r4} |
| 487 | tst ip, #4 |
| 488 | movne r3, r7, pull #8 |
| 489 | USER( ldrnet r7, [r1], #4) @ May fault |
| 490 | orrne r3, r3, r7, push #24 |
| 491 | strne r3, [r0], #4 |
| 492 | ands ip, ip, #3 |
| 493 | beq .cfu_1fupi |
| 494 | .cfu_1nowords: mov r3, r7, lsr #byte(1) |
| 495 | teq ip, #0 |
| 496 | beq .cfu_finished |
| 497 | cmp ip, #2 |
| 498 | strb r3, [r0], #1 |
| 499 | movge r3, r7, lsr #byte(2) |
| 500 | strgeb r3, [r0], #1 |
| 501 | movgt r3, r7, lsr #byte(3) |
| 502 | strgtb r3, [r0], #1 |
| 503 | b .cfu_finished |
| 504 | |
| 505 | .cfu_2fupi: subs r2, r2, #4 |
| 506 | addmi ip, r2, #4 |
| 507 | bmi .cfu_2nowords |
| 508 | mov r3, r7, pull #16 |
| 509 | USER( ldrt r7, [r1], #4) @ May fault |
| 510 | orr r3, r3, r7, push #16 |
| 511 | str r3, [r0], #4 |
| 512 | mov ip, r1, lsl #32 - PAGE_SHIFT |
| 513 | rsb ip, ip, #0 |
| 514 | movs ip, ip, lsr #32 - PAGE_SHIFT |
| 515 | beq .cfu_2fupi |
| 516 | cmp r2, ip |
| 517 | movlt ip, r2 |
| 518 | sub r2, r2, ip |
| 519 | subs ip, ip, #16 |
| 520 | blt .cfu_2rem8lp |
| 521 | |
| 522 | .cfu_2cpy8lp: mov r3, r7, pull #16 |
| 523 | ldmia r1!, {r4 - r7} @ Shouldnt fault |
| 524 | orr r3, r3, r4, push #16 |
| 525 | mov r4, r4, pull #16 |
| 526 | orr r4, r4, r5, push #16 |
| 527 | mov r5, r5, pull #16 |
| 528 | orr r5, r5, r6, push #16 |
| 529 | mov r6, r6, pull #16 |
| 530 | orr r6, r6, r7, push #16 |
| 531 | stmia r0!, {r3 - r6} |
| 532 | subs ip, ip, #16 |
| 533 | bpl .cfu_2cpy8lp |
| 534 | .cfu_2rem8lp: tst ip, #8 |
| 535 | movne r3, r7, pull #16 |
| 536 | ldmneia r1!, {r4, r7} @ Shouldnt fault |
| 537 | orrne r3, r3, r4, push #16 |
| 538 | movne r4, r4, pull #16 |
| 539 | orrne r4, r4, r7, push #16 |
| 540 | stmneia r0!, {r3 - r4} |
| 541 | tst ip, #4 |
| 542 | movne r3, r7, pull #16 |
| 543 | USER( ldrnet r7, [r1], #4) @ May fault |
| 544 | orrne r3, r3, r7, push #16 |
| 545 | strne r3, [r0], #4 |
| 546 | ands ip, ip, #3 |
| 547 | beq .cfu_2fupi |
| 548 | .cfu_2nowords: mov r3, r7, lsr #byte(2) |
| 549 | teq ip, #0 |
| 550 | beq .cfu_finished |
| 551 | cmp ip, #2 |
| 552 | strb r3, [r0], #1 |
| 553 | movge r3, r7, lsr #byte(3) |
| 554 | strgeb r3, [r0], #1 |
| 555 | USER( ldrgtbt r3, [r1], #0) @ May fault |
| 556 | strgtb r3, [r0], #1 |
| 557 | b .cfu_finished |
| 558 | |
| 559 | .cfu_3fupi: subs r2, r2, #4 |
| 560 | addmi ip, r2, #4 |
| 561 | bmi .cfu_3nowords |
| 562 | mov r3, r7, pull #24 |
| 563 | USER( ldrt r7, [r1], #4) @ May fault |
| 564 | orr r3, r3, r7, push #8 |
| 565 | str r3, [r0], #4 |
| 566 | mov ip, r1, lsl #32 - PAGE_SHIFT |
| 567 | rsb ip, ip, #0 |
| 568 | movs ip, ip, lsr #32 - PAGE_SHIFT |
| 569 | beq .cfu_3fupi |
| 570 | cmp r2, ip |
| 571 | movlt ip, r2 |
| 572 | sub r2, r2, ip |
| 573 | subs ip, ip, #16 |
| 574 | blt .cfu_3rem8lp |
| 575 | |
| 576 | .cfu_3cpy8lp: mov r3, r7, pull #24 |
| 577 | ldmia r1!, {r4 - r7} @ Shouldnt fault |
| 578 | orr r3, r3, r4, push #8 |
| 579 | mov r4, r4, pull #24 |
| 580 | orr r4, r4, r5, push #8 |
| 581 | mov r5, r5, pull #24 |
| 582 | orr r5, r5, r6, push #8 |
| 583 | mov r6, r6, pull #24 |
| 584 | orr r6, r6, r7, push #8 |
| 585 | stmia r0!, {r3 - r6} |
| 586 | subs ip, ip, #16 |
| 587 | bpl .cfu_3cpy8lp |
| 588 | .cfu_3rem8lp: tst ip, #8 |
| 589 | movne r3, r7, pull #24 |
| 590 | ldmneia r1!, {r4, r7} @ Shouldnt fault |
| 591 | orrne r3, r3, r4, push #8 |
| 592 | movne r4, r4, pull #24 |
| 593 | orrne r4, r4, r7, push #8 |
| 594 | stmneia r0!, {r3 - r4} |
| 595 | tst ip, #4 |
| 596 | movne r3, r7, pull #24 |
| 597 | USER( ldrnet r7, [r1], #4) @ May fault |
| 598 | orrne r3, r3, r7, push #8 |
| 599 | strne r3, [r0], #4 |
| 600 | ands ip, ip, #3 |
| 601 | beq .cfu_3fupi |
| 602 | .cfu_3nowords: mov r3, r7, lsr #byte(3) |
| 603 | teq ip, #0 |
| 604 | beq .cfu_finished |
| 605 | cmp ip, #2 |
| 606 | strb r3, [r0], #1 |
| 607 | USER( ldrgebt r3, [r1], #1) @ May fault |
| 608 | strgeb r3, [r0], #1 |
| 609 | USER( ldrgtbt r3, [r1], #1) @ May fault |
| 610 | strgtb r3, [r0], #1 |
| 611 | b .cfu_finished |
| 612 | |
| 613 | .section .fixup,"ax" |
| 614 | .align 0 |
| 615 | /* |
| 616 | * We took an exception. r0 contains a pointer to |
| 617 | * the byte not copied. |
| 618 | */ |
| 619 | 9001: ldr r2, [sp], #4 @ void *to |
| 620 | sub r2, r0, r2 @ bytes copied |
| 621 | ldr r1, [sp], #4 @ unsigned long count |
| 622 | subs r4, r1, r2 @ bytes left to copy |
| 623 | movne r1, r4 |
| 624 | blne __memzero |
| 625 | mov r0, r4 |
| 626 | LOADREGS(fd,sp!, {r4 - r7, pc}) |
| 627 | .previous |
| 628 | |
| 629 | /* Prototype: int uaccess_user_clear_user(void *addr, size_t sz) |
| 630 | * Purpose : clear some user memory |
| 631 | * Params : addr - user memory address to clear |
| 632 | * : sz - number of bytes to clear |
| 633 | * Returns : number of bytes NOT cleared |
| 634 | */ |
| 635 | ENTRY(uaccess_user_clear_user) |
| 636 | stmfd sp!, {r1, lr} |
| 637 | mov r2, #0 |
| 638 | cmp r1, #4 |
| 639 | blt 2f |
| 640 | ands ip, r0, #3 |
| 641 | beq 1f |
| 642 | cmp ip, #2 |
| 643 | USER( strbt r2, [r0], #1) |
| 644 | USER( strlebt r2, [r0], #1) |
| 645 | USER( strltbt r2, [r0], #1) |
| 646 | rsb ip, ip, #4 |
| 647 | sub r1, r1, ip @ 7 6 5 4 3 2 1 |
| 648 | 1: subs r1, r1, #8 @ -1 -2 -3 -4 -5 -6 -7 |
| 649 | USER( strplt r2, [r0], #4) |
| 650 | USER( strplt r2, [r0], #4) |
| 651 | bpl 1b |
| 652 | adds r1, r1, #4 @ 3 2 1 0 -1 -2 -3 |
| 653 | USER( strplt r2, [r0], #4) |
| 654 | 2: tst r1, #2 @ 1x 1x 0x 0x 1x 1x 0x |
| 655 | USER( strnebt r2, [r0], #1) |
| 656 | USER( strnebt r2, [r0], #1) |
| 657 | tst r1, #1 @ x1 x0 x1 x0 x1 x0 x1 |
| 658 | USER( strnebt r2, [r0], #1) |
| 659 | mov r0, #0 |
| 660 | LOADREGS(fd,sp!, {r1, pc}) |
| 661 | |
| 662 | .section .fixup,"ax" |
| 663 | .align 0 |
| 664 | 9001: LOADREGS(fd,sp!, {r0, pc}) |
| 665 | .previous |
| 666 | |
| 667 | /* |
| 668 | * Copy a string from user space to kernel space. |
| 669 | * r0 = dst, r1 = src, r2 = byte length |
| 670 | * returns the number of characters copied (strlen of copied string), |
| 671 | * -EFAULT on exception, or "len" if we fill the whole buffer |
| 672 | */ |
| 673 | ENTRY(uaccess_user_strncpy_from_user) |
| 674 | save_lr |
| 675 | mov ip, r1 |
| 676 | 1: subs r2, r2, #1 |
| 677 | USER( ldrplbt r3, [r1], #1) |
| 678 | bmi 2f |
| 679 | strb r3, [r0], #1 |
| 680 | teq r3, #0 |
| 681 | bne 1b |
| 682 | sub r1, r1, #1 @ take NUL character out of count |
| 683 | 2: sub r0, r1, ip |
| 684 | restore_pc |
| 685 | |
| 686 | .section .fixup,"ax" |
| 687 | .align 0 |
| 688 | 9001: mov r3, #0 |
| 689 | strb r3, [r0, #0] @ null terminate |
| 690 | mov r0, #-EFAULT |
| 691 | restore_pc |
| 692 | .previous |
| 693 | |
| 694 | /* Prototype: unsigned long uaccess_user_strnlen_user(const char *str, long n) |
| 695 | * Purpose : get length of a string in user memory |
| 696 | * Params : str - address of string in user memory |
| 697 | * Returns : length of string *including terminator* |
| 698 | * or zero on exception, or n + 1 if too long |
| 699 | */ |
| 700 | ENTRY(uaccess_user_strnlen_user) |
| 701 | save_lr |
| 702 | mov r2, r0 |
| 703 | 1: |
| 704 | USER( ldrbt r3, [r0], #1) |
| 705 | teq r3, #0 |
| 706 | beq 2f |
| 707 | subs r1, r1, #1 |
| 708 | bne 1b |
| 709 | add r0, r0, #1 |
| 710 | 2: sub r0, r0, r2 |
| 711 | restore_pc |
| 712 | |
| 713 | .section .fixup,"ax" |
| 714 | .align 0 |
| 715 | 9001: mov r0, #0 |
| 716 | restore_pc |
| 717 | .previous |
| 718 | |