1/* 2 * Copyright (C) 2006-2008 Nokia Corporation 3 * 4 * This program is free software; you can redistribute it and/or modify it 5 * under the terms of the GNU General Public License version 2 as published by 6 * the Free Software Foundation. 7 * 8 * This program is distributed in the hope that it will be useful, but WITHOUT 9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 11 * more details. 12 * 13 * You should have received a copy of the GNU General Public License along with 14 * this program; see the file COPYING. If not, write to the Free Software 15 * Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. 16 * 17 * Test OOB read and write on MTD device. 18 * 19 * Author: Adrian Hunter <ext-adrian.hunter@nokia.com> 20 */ 21 22#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 23 24#include <asm/div64.h> 25#include <linux/init.h> 26#include <linux/module.h> 27#include <linux/moduleparam.h> 28#include <linux/err.h> 29#include <linux/mtd/mtd.h> 30#include <linux/slab.h> 31#include <linux/sched.h> 32#include <linux/random.h> 33 34#include "mtd_test.h" 35 36static int dev = -EINVAL; 37static int bitflip_limit; 38module_param(dev, int, S_IRUGO); 39MODULE_PARM_DESC(dev, "MTD device number to use"); 40module_param(bitflip_limit, int, S_IRUGO); 41MODULE_PARM_DESC(bitflip_limit, "Max. allowed bitflips per page"); 42 43static struct mtd_info *mtd; 44static unsigned char *readbuf; 45static unsigned char *writebuf; 46static unsigned char *bbt; 47 48static int ebcnt; 49static int pgcnt; 50static int errcnt; 51static int use_offset; 52static int use_len; 53static int use_len_max; 54static int vary_offset; 55static struct rnd_state rnd_state; 56 57static void do_vary_offset(void) 58{ 59 use_len -= 1; 60 if (use_len < 1) { 61 use_offset += 1; 62 if (use_offset >= use_len_max) 63 use_offset = 0; 64 use_len = use_len_max - use_offset; 65 } 66} 67 68static int write_eraseblock(int ebnum) 69{ 70 int i; 71 struct mtd_oob_ops ops; 72 int err = 0; 73 loff_t addr = (loff_t)ebnum * mtd->erasesize; 74 75 prandom_bytes_state(&rnd_state, writebuf, use_len_max * pgcnt); 76 for (i = 0; i < pgcnt; ++i, addr += mtd->writesize) { 77 ops.mode = MTD_OPS_AUTO_OOB; 78 ops.len = 0; 79 ops.retlen = 0; 80 ops.ooblen = use_len; 81 ops.oobretlen = 0; 82 ops.ooboffs = use_offset; 83 ops.datbuf = NULL; 84 ops.oobbuf = writebuf + (use_len_max * i) + use_offset; 85 err = mtd_write_oob(mtd, addr, &ops); 86 if (err || ops.oobretlen != use_len) { 87 pr_err("error: writeoob failed at %#llx\n", 88 (long long)addr); 89 pr_err("error: use_len %d, use_offset %d\n", 90 use_len, use_offset); 91 errcnt += 1; 92 return err ? err : -1; 93 } 94 if (vary_offset) 95 do_vary_offset(); 96 } 97 98 return err; 99} 100 101static int write_whole_device(void) 102{ 103 int err; 104 unsigned int i; 105 106 pr_info("writing OOBs of whole device\n"); 107 for (i = 0; i < ebcnt; ++i) { 108 if (bbt[i]) 109 continue; 110 err = write_eraseblock(i); 111 if (err) 112 return err; 113 if (i % 256 == 0) 114 pr_info("written up to eraseblock %u\n", i); 115 116 err = mtdtest_relax(); 117 if (err) 118 return err; 119 } 120 pr_info("written %u eraseblocks\n", i); 121 return 0; 122} 123 124/* 125 * Display the address, offset and data bytes at comparison failure. 126 * Return number of bitflips encountered. 127 */ 128static size_t memcmpshowoffset(loff_t addr, loff_t offset, const void *cs, 129 const void *ct, size_t count) 130{ 131 const unsigned char *su1, *su2; 132 int res; 133 size_t i = 0; 134 size_t bitflips = 0; 135 136 for (su1 = cs, su2 = ct; 0 < count; ++su1, ++su2, count--, i++) { 137 res = *su1 ^ *su2; 138 if (res) { 139 pr_info("error @addr[0x%lx:0x%lx] 0x%x -> 0x%x diff 0x%x\n", 140 (unsigned long)addr, (unsigned long)offset + i, 141 *su1, *su2, res); 142 bitflips += hweight8(res); 143 } 144 } 145 146 return bitflips; 147} 148 149#define memcmpshow(addr, cs, ct, count) memcmpshowoffset((addr), 0, (cs), (ct),\ 150 (count)) 151 152/* 153 * Compare with 0xff and show the address, offset and data bytes at 154 * comparison failure. Return number of bitflips encountered. 155 */ 156static size_t memffshow(loff_t addr, loff_t offset, const void *cs, 157 size_t count) 158{ 159 const unsigned char *su1; 160 int res; 161 size_t i = 0; 162 size_t bitflips = 0; 163 164 for (su1 = cs; 0 < count; ++su1, count--, i++) { 165 res = *su1 ^ 0xff; 166 if (res) { 167 pr_info("error @addr[0x%lx:0x%lx] 0x%x -> 0xff diff 0x%x\n", 168 (unsigned long)addr, (unsigned long)offset + i, 169 *su1, res); 170 bitflips += hweight8(res); 171 } 172 } 173 174 return bitflips; 175} 176 177static int verify_eraseblock(int ebnum) 178{ 179 int i; 180 struct mtd_oob_ops ops; 181 int err = 0; 182 loff_t addr = (loff_t)ebnum * mtd->erasesize; 183 size_t bitflips; 184 185 prandom_bytes_state(&rnd_state, writebuf, use_len_max * pgcnt); 186 for (i = 0; i < pgcnt; ++i, addr += mtd->writesize) { 187 ops.mode = MTD_OPS_AUTO_OOB; 188 ops.len = 0; 189 ops.retlen = 0; 190 ops.ooblen = use_len; 191 ops.oobretlen = 0; 192 ops.ooboffs = use_offset; 193 ops.datbuf = NULL; 194 ops.oobbuf = readbuf; 195 err = mtd_read_oob(mtd, addr, &ops); 196 if (err || ops.oobretlen != use_len) { 197 pr_err("error: readoob failed at %#llx\n", 198 (long long)addr); 199 errcnt += 1; 200 return err ? err : -1; 201 } 202 203 bitflips = memcmpshow(addr, readbuf, 204 writebuf + (use_len_max * i) + use_offset, 205 use_len); 206 if (bitflips > bitflip_limit) { 207 pr_err("error: verify failed at %#llx\n", 208 (long long)addr); 209 errcnt += 1; 210 if (errcnt > 1000) { 211 pr_err("error: too many errors\n"); 212 return -1; 213 } 214 } else if (bitflips) { 215 pr_info("ignoring error as within bitflip_limit\n"); 216 } 217 218 if (use_offset != 0 || use_len < mtd->ecclayout->oobavail) { 219 int k; 220 221 ops.mode = MTD_OPS_AUTO_OOB; 222 ops.len = 0; 223 ops.retlen = 0; 224 ops.ooblen = mtd->ecclayout->oobavail; 225 ops.oobretlen = 0; 226 ops.ooboffs = 0; 227 ops.datbuf = NULL; 228 ops.oobbuf = readbuf; 229 err = mtd_read_oob(mtd, addr, &ops); 230 if (err || ops.oobretlen != mtd->ecclayout->oobavail) { 231 pr_err("error: readoob failed at %#llx\n", 232 (long long)addr); 233 errcnt += 1; 234 return err ? err : -1; 235 } 236 bitflips = memcmpshowoffset(addr, use_offset, 237 readbuf + use_offset, 238 writebuf + (use_len_max * i) + use_offset, 239 use_len); 240 241 /* verify pre-offset area for 0xff */ 242 bitflips += memffshow(addr, 0, readbuf, use_offset); 243 244 /* verify post-(use_offset + use_len) area for 0xff */ 245 k = use_offset + use_len; 246 bitflips += memffshow(addr, k, readbuf + k, 247 mtd->ecclayout->oobavail - k); 248 249 if (bitflips > bitflip_limit) { 250 pr_err("error: verify failed at %#llx\n", 251 (long long)addr); 252 errcnt += 1; 253 if (errcnt > 1000) { 254 pr_err("error: too many errors\n"); 255 return -1; 256 } 257 } else if (bitflips) { 258 pr_info("ignoring errors as within bitflip limit\n"); 259 } 260 } 261 if (vary_offset) 262 do_vary_offset(); 263 } 264 return err; 265} 266 267static int verify_eraseblock_in_one_go(int ebnum) 268{ 269 struct mtd_oob_ops ops; 270 int err = 0; 271 loff_t addr = (loff_t)ebnum * mtd->erasesize; 272 size_t len = mtd->ecclayout->oobavail * pgcnt; 273 size_t oobavail = mtd->ecclayout->oobavail; 274 size_t bitflips; 275 int i; 276 277 prandom_bytes_state(&rnd_state, writebuf, len); 278 ops.mode = MTD_OPS_AUTO_OOB; 279 ops.len = 0; 280 ops.retlen = 0; 281 ops.ooblen = len; 282 ops.oobretlen = 0; 283 ops.ooboffs = 0; 284 ops.datbuf = NULL; 285 ops.oobbuf = readbuf; 286 287 /* read entire block's OOB at one go */ 288 err = mtd_read_oob(mtd, addr, &ops); 289 if (err || ops.oobretlen != len) { 290 pr_err("error: readoob failed at %#llx\n", 291 (long long)addr); 292 errcnt += 1; 293 return err ? err : -1; 294 } 295 296 /* verify one page OOB at a time for bitflip per page limit check */ 297 for (i = 0; i < pgcnt; ++i, addr += mtd->writesize) { 298 bitflips = memcmpshow(addr, readbuf + (i * oobavail), 299 writebuf + (i * oobavail), oobavail); 300 if (bitflips > bitflip_limit) { 301 pr_err("error: verify failed at %#llx\n", 302 (long long)addr); 303 errcnt += 1; 304 if (errcnt > 1000) { 305 pr_err("error: too many errors\n"); 306 return -1; 307 } 308 } else if (bitflips) { 309 pr_info("ignoring error as within bitflip_limit\n"); 310 } 311 } 312 313 return err; 314} 315 316static int verify_all_eraseblocks(void) 317{ 318 int err; 319 unsigned int i; 320 321 pr_info("verifying all eraseblocks\n"); 322 for (i = 0; i < ebcnt; ++i) { 323 if (bbt[i]) 324 continue; 325 err = verify_eraseblock(i); 326 if (err) 327 return err; 328 if (i % 256 == 0) 329 pr_info("verified up to eraseblock %u\n", i); 330 331 err = mtdtest_relax(); 332 if (err) 333 return err; 334 } 335 pr_info("verified %u eraseblocks\n", i); 336 return 0; 337} 338 339static int __init mtd_oobtest_init(void) 340{ 341 int err = 0; 342 unsigned int i; 343 uint64_t tmp; 344 struct mtd_oob_ops ops; 345 loff_t addr = 0, addr0; 346 347 printk(KERN_INFO "\n"); 348 printk(KERN_INFO "=================================================\n"); 349 350 if (dev < 0) { 351 pr_info("Please specify a valid mtd-device via module parameter\n"); 352 pr_crit("CAREFUL: This test wipes all data on the specified MTD device!\n"); 353 return -EINVAL; 354 } 355 356 pr_info("MTD device: %d\n", dev); 357 358 mtd = get_mtd_device(NULL, dev); 359 if (IS_ERR(mtd)) { 360 err = PTR_ERR(mtd); 361 pr_err("error: cannot get MTD device\n"); 362 return err; 363 } 364 365 if (!mtd_type_is_nand(mtd)) { 366 pr_info("this test requires NAND flash\n"); 367 goto out; 368 } 369 370 tmp = mtd->size; 371 do_div(tmp, mtd->erasesize); 372 ebcnt = tmp; 373 pgcnt = mtd->erasesize / mtd->writesize; 374 375 pr_info("MTD device size %llu, eraseblock size %u, " 376 "page size %u, count of eraseblocks %u, pages per " 377 "eraseblock %u, OOB size %u\n", 378 (unsigned long long)mtd->size, mtd->erasesize, 379 mtd->writesize, ebcnt, pgcnt, mtd->oobsize); 380 381 err = -ENOMEM; 382 readbuf = kmalloc(mtd->erasesize, GFP_KERNEL); 383 if (!readbuf) 384 goto out; 385 writebuf = kmalloc(mtd->erasesize, GFP_KERNEL); 386 if (!writebuf) 387 goto out; 388 bbt = kzalloc(ebcnt, GFP_KERNEL); 389 if (!bbt) 390 goto out; 391 392 err = mtdtest_scan_for_bad_eraseblocks(mtd, bbt, 0, ebcnt); 393 if (err) 394 goto out; 395 396 use_offset = 0; 397 use_len = mtd->ecclayout->oobavail; 398 use_len_max = mtd->ecclayout->oobavail; 399 vary_offset = 0; 400 401 /* First test: write all OOB, read it back and verify */ 402 pr_info("test 1 of 5\n"); 403 404 err = mtdtest_erase_good_eraseblocks(mtd, bbt, 0, ebcnt); 405 if (err) 406 goto out; 407 408 prandom_seed_state(&rnd_state, 1); 409 err = write_whole_device(); 410 if (err) 411 goto out; 412 413 prandom_seed_state(&rnd_state, 1); 414 err = verify_all_eraseblocks(); 415 if (err) 416 goto out; 417 418 /* 419 * Second test: write all OOB, a block at a time, read it back and 420 * verify. 421 */ 422 pr_info("test 2 of 5\n"); 423 424 err = mtdtest_erase_good_eraseblocks(mtd, bbt, 0, ebcnt); 425 if (err) 426 goto out; 427 428 prandom_seed_state(&rnd_state, 3); 429 err = write_whole_device(); 430 if (err) 431 goto out; 432 433 /* Check all eraseblocks */ 434 prandom_seed_state(&rnd_state, 3); 435 pr_info("verifying all eraseblocks\n"); 436 for (i = 0; i < ebcnt; ++i) { 437 if (bbt[i]) 438 continue; 439 err = verify_eraseblock_in_one_go(i); 440 if (err) 441 goto out; 442 if (i % 256 == 0) 443 pr_info("verified up to eraseblock %u\n", i); 444 445 err = mtdtest_relax(); 446 if (err) 447 goto out; 448 } 449 pr_info("verified %u eraseblocks\n", i); 450 451 /* 452 * Third test: write OOB at varying offsets and lengths, read it back 453 * and verify. 454 */ 455 pr_info("test 3 of 5\n"); 456 457 err = mtdtest_erase_good_eraseblocks(mtd, bbt, 0, ebcnt); 458 if (err) 459 goto out; 460 461 /* Write all eraseblocks */ 462 use_offset = 0; 463 use_len = mtd->ecclayout->oobavail; 464 use_len_max = mtd->ecclayout->oobavail; 465 vary_offset = 1; 466 prandom_seed_state(&rnd_state, 5); 467 468 err = write_whole_device(); 469 if (err) 470 goto out; 471 472 /* Check all eraseblocks */ 473 use_offset = 0; 474 use_len = mtd->ecclayout->oobavail; 475 use_len_max = mtd->ecclayout->oobavail; 476 vary_offset = 1; 477 prandom_seed_state(&rnd_state, 5); 478 err = verify_all_eraseblocks(); 479 if (err) 480 goto out; 481 482 use_offset = 0; 483 use_len = mtd->ecclayout->oobavail; 484 use_len_max = mtd->ecclayout->oobavail; 485 vary_offset = 0; 486 487 /* Fourth test: try to write off end of device */ 488 pr_info("test 4 of 5\n"); 489 490 err = mtdtest_erase_good_eraseblocks(mtd, bbt, 0, ebcnt); 491 if (err) 492 goto out; 493 494 addr0 = 0; 495 for (i = 0; i < ebcnt && bbt[i]; ++i) 496 addr0 += mtd->erasesize; 497 498 /* Attempt to write off end of OOB */ 499 ops.mode = MTD_OPS_AUTO_OOB; 500 ops.len = 0; 501 ops.retlen = 0; 502 ops.ooblen = 1; 503 ops.oobretlen = 0; 504 ops.ooboffs = mtd->ecclayout->oobavail; 505 ops.datbuf = NULL; 506 ops.oobbuf = writebuf; 507 pr_info("attempting to start write past end of OOB\n"); 508 pr_info("an error is expected...\n"); 509 err = mtd_write_oob(mtd, addr0, &ops); 510 if (err) { 511 pr_info("error occurred as expected\n"); 512 err = 0; 513 } else { 514 pr_err("error: can write past end of OOB\n"); 515 errcnt += 1; 516 } 517 518 /* Attempt to read off end of OOB */ 519 ops.mode = MTD_OPS_AUTO_OOB; 520 ops.len = 0; 521 ops.retlen = 0; 522 ops.ooblen = 1; 523 ops.oobretlen = 0; 524 ops.ooboffs = mtd->ecclayout->oobavail; 525 ops.datbuf = NULL; 526 ops.oobbuf = readbuf; 527 pr_info("attempting to start read past end of OOB\n"); 528 pr_info("an error is expected...\n"); 529 err = mtd_read_oob(mtd, addr0, &ops); 530 if (err) { 531 pr_info("error occurred as expected\n"); 532 err = 0; 533 } else { 534 pr_err("error: can read past end of OOB\n"); 535 errcnt += 1; 536 } 537 538 if (bbt[ebcnt - 1]) 539 pr_info("skipping end of device tests because last " 540 "block is bad\n"); 541 else { 542 /* Attempt to write off end of device */ 543 ops.mode = MTD_OPS_AUTO_OOB; 544 ops.len = 0; 545 ops.retlen = 0; 546 ops.ooblen = mtd->ecclayout->oobavail + 1; 547 ops.oobretlen = 0; 548 ops.ooboffs = 0; 549 ops.datbuf = NULL; 550 ops.oobbuf = writebuf; 551 pr_info("attempting to write past end of device\n"); 552 pr_info("an error is expected...\n"); 553 err = mtd_write_oob(mtd, mtd->size - mtd->writesize, &ops); 554 if (err) { 555 pr_info("error occurred as expected\n"); 556 err = 0; 557 } else { 558 pr_err("error: wrote past end of device\n"); 559 errcnt += 1; 560 } 561 562 /* Attempt to read off end of device */ 563 ops.mode = MTD_OPS_AUTO_OOB; 564 ops.len = 0; 565 ops.retlen = 0; 566 ops.ooblen = mtd->ecclayout->oobavail + 1; 567 ops.oobretlen = 0; 568 ops.ooboffs = 0; 569 ops.datbuf = NULL; 570 ops.oobbuf = readbuf; 571 pr_info("attempting to read past end of device\n"); 572 pr_info("an error is expected...\n"); 573 err = mtd_read_oob(mtd, mtd->size - mtd->writesize, &ops); 574 if (err) { 575 pr_info("error occurred as expected\n"); 576 err = 0; 577 } else { 578 pr_err("error: read past end of device\n"); 579 errcnt += 1; 580 } 581 582 err = mtdtest_erase_eraseblock(mtd, ebcnt - 1); 583 if (err) 584 goto out; 585 586 /* Attempt to write off end of device */ 587 ops.mode = MTD_OPS_AUTO_OOB; 588 ops.len = 0; 589 ops.retlen = 0; 590 ops.ooblen = mtd->ecclayout->oobavail; 591 ops.oobretlen = 0; 592 ops.ooboffs = 1; 593 ops.datbuf = NULL; 594 ops.oobbuf = writebuf; 595 pr_info("attempting to write past end of device\n"); 596 pr_info("an error is expected...\n"); 597 err = mtd_write_oob(mtd, mtd->size - mtd->writesize, &ops); 598 if (err) { 599 pr_info("error occurred as expected\n"); 600 err = 0; 601 } else { 602 pr_err("error: wrote past end of device\n"); 603 errcnt += 1; 604 } 605 606 /* Attempt to read off end of device */ 607 ops.mode = MTD_OPS_AUTO_OOB; 608 ops.len = 0; 609 ops.retlen = 0; 610 ops.ooblen = mtd->ecclayout->oobavail; 611 ops.oobretlen = 0; 612 ops.ooboffs = 1; 613 ops.datbuf = NULL; 614 ops.oobbuf = readbuf; 615 pr_info("attempting to read past end of device\n"); 616 pr_info("an error is expected...\n"); 617 err = mtd_read_oob(mtd, mtd->size - mtd->writesize, &ops); 618 if (err) { 619 pr_info("error occurred as expected\n"); 620 err = 0; 621 } else { 622 pr_err("error: read past end of device\n"); 623 errcnt += 1; 624 } 625 } 626 627 /* Fifth test: write / read across block boundaries */ 628 pr_info("test 5 of 5\n"); 629 630 /* Erase all eraseblocks */ 631 err = mtdtest_erase_good_eraseblocks(mtd, bbt, 0, ebcnt); 632 if (err) 633 goto out; 634 635 /* Write all eraseblocks */ 636 prandom_seed_state(&rnd_state, 11); 637 pr_info("writing OOBs of whole device\n"); 638 for (i = 0; i < ebcnt - 1; ++i) { 639 int cnt = 2; 640 int pg; 641 size_t sz = mtd->ecclayout->oobavail; 642 if (bbt[i] || bbt[i + 1]) 643 continue; 644 addr = (loff_t)(i + 1) * mtd->erasesize - mtd->writesize; 645 prandom_bytes_state(&rnd_state, writebuf, sz * cnt); 646 for (pg = 0; pg < cnt; ++pg) { 647 ops.mode = MTD_OPS_AUTO_OOB; 648 ops.len = 0; 649 ops.retlen = 0; 650 ops.ooblen = sz; 651 ops.oobretlen = 0; 652 ops.ooboffs = 0; 653 ops.datbuf = NULL; 654 ops.oobbuf = writebuf + pg * sz; 655 err = mtd_write_oob(mtd, addr, &ops); 656 if (err) 657 goto out; 658 if (i % 256 == 0) 659 pr_info("written up to eraseblock %u\n", i); 660 661 err = mtdtest_relax(); 662 if (err) 663 goto out; 664 665 addr += mtd->writesize; 666 } 667 } 668 pr_info("written %u eraseblocks\n", i); 669 670 /* Check all eraseblocks */ 671 prandom_seed_state(&rnd_state, 11); 672 pr_info("verifying all eraseblocks\n"); 673 for (i = 0; i < ebcnt - 1; ++i) { 674 if (bbt[i] || bbt[i + 1]) 675 continue; 676 prandom_bytes_state(&rnd_state, writebuf, 677 mtd->ecclayout->oobavail * 2); 678 addr = (loff_t)(i + 1) * mtd->erasesize - mtd->writesize; 679 ops.mode = MTD_OPS_AUTO_OOB; 680 ops.len = 0; 681 ops.retlen = 0; 682 ops.ooblen = mtd->ecclayout->oobavail * 2; 683 ops.oobretlen = 0; 684 ops.ooboffs = 0; 685 ops.datbuf = NULL; 686 ops.oobbuf = readbuf; 687 err = mtd_read_oob(mtd, addr, &ops); 688 if (err) 689 goto out; 690 if (memcmpshow(addr, readbuf, writebuf, 691 mtd->ecclayout->oobavail * 2)) { 692 pr_err("error: verify failed at %#llx\n", 693 (long long)addr); 694 errcnt += 1; 695 if (errcnt > 1000) { 696 pr_err("error: too many errors\n"); 697 goto out; 698 } 699 } 700 if (i % 256 == 0) 701 pr_info("verified up to eraseblock %u\n", i); 702 703 err = mtdtest_relax(); 704 if (err) 705 goto out; 706 } 707 pr_info("verified %u eraseblocks\n", i); 708 709 pr_info("finished with %d errors\n", errcnt); 710out: 711 kfree(bbt); 712 kfree(writebuf); 713 kfree(readbuf); 714 put_mtd_device(mtd); 715 if (err) 716 pr_info("error %d occurred\n", err); 717 printk(KERN_INFO "=================================================\n"); 718 return err; 719} 720module_init(mtd_oobtest_init); 721 722static void __exit mtd_oobtest_exit(void) 723{ 724 return; 725} 726module_exit(mtd_oobtest_exit); 727 728MODULE_DESCRIPTION("Out-of-band test module"); 729MODULE_AUTHOR("Adrian Hunter"); 730MODULE_LICENSE("GPL"); 731