1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Author: Hanlu Li <lihanlu@loongson.cn> 4 * Huacai Chen <chenhuacai@loongson.cn> 5 * 6 * Copyright (C) 2020-2022 Loongson Technology Corporation Limited 7 * 8 * Derived from MIPS: 9 * Copyright (C) 1992 Ross Biro 10 * Copyright (C) Linus Torvalds 11 * Copyright (C) 1994, 95, 96, 97, 98, 2000 Ralf Baechle 12 * Copyright (C) 1996 David S. Miller 13 * Kevin D. Kissell, kevink@mips.com and Carsten Langgaard, carstenl@mips.com 14 * Copyright (C) 1999 MIPS Technologies, Inc. 15 * Copyright (C) 2000 Ulf Carlsson 16 */ 17 #include <linux/kernel.h> 18 #include <linux/audit.h> 19 #include <linux/compiler.h> 20 #include <linux/context_tracking.h> 21 #include <linux/elf.h> 22 #include <linux/errno.h> 23 #include <linux/hw_breakpoint.h> 24 #include <linux/mm.h> 25 #include <linux/nospec.h> 26 #include <linux/ptrace.h> 27 #include <linux/regset.h> 28 #include <linux/sched.h> 29 #include <linux/sched/task_stack.h> 30 #include <linux/security.h> 31 #include <linux/smp.h> 32 #include <linux/stddef.h> 33 #include <linux/seccomp.h> 34 #include <linux/thread_info.h> 35 #include <linux/uaccess.h> 36 37 #include <asm/byteorder.h> 38 #include <asm/cpu.h> 39 #include <asm/cpu-info.h> 40 #include <asm/fpu.h> 41 #include <asm/lbt.h> 42 #include <asm/loongarch.h> 43 #include <asm/page.h> 44 #include <asm/pgtable.h> 45 #include <asm/processor.h> 46 #include <asm/ptrace.h> 47 #include <asm/reg.h> 48 #include <asm/syscall.h> 49 50 static void init_fp_ctx(struct task_struct *target) 51 { 52 /* The target already has context */ 53 if (tsk_used_math(target)) 54 return; 55 56 /* Begin with data registers set to all 1s... */ 57 memset(&target->thread.fpu.fpr, ~0, sizeof(target->thread.fpu.fpr)); 58 set_stopped_child_used_math(target); 59 } 60 61 /* 62 * Called by kernel/ptrace.c when detaching.. 63 * 64 * Make sure single step bits etc are not set. 65 */ 66 void ptrace_disable(struct task_struct *child) 67 { 68 /* Don't load the watchpoint registers for the ex-child. */ 69 clear_tsk_thread_flag(child, TIF_LOAD_WATCH); 70 clear_tsk_thread_flag(child, TIF_SINGLESTEP); 71 } 72 73 /* regset get/set implementations */ 74 75 static int gpr_get(struct task_struct *target, 76 const struct user_regset *regset, 77 struct membuf to) 78 { 79 int r; 80 struct pt_regs *regs = task_pt_regs(target); 81 82 r = membuf_write(&to, ®s->regs, sizeof(u64) * GPR_NUM); 83 r = membuf_write(&to, ®s->orig_a0, sizeof(u64)); 84 r = membuf_write(&to, ®s->csr_era, sizeof(u64)); 85 r = membuf_write(&to, ®s->csr_badvaddr, sizeof(u64)); 86 87 return r; 88 } 89 90 static int gpr_set(struct task_struct *target, 91 const struct user_regset *regset, 92 unsigned int pos, unsigned int count, 93 const void *kbuf, const void __user *ubuf) 94 { 95 int err; 96 int a0_start = sizeof(u64) * GPR_NUM; 97 int era_start = a0_start + sizeof(u64); 98 int badvaddr_start = era_start + sizeof(u64); 99 struct pt_regs *regs = task_pt_regs(target); 100 101 err = user_regset_copyin(&pos, &count, &kbuf, &ubuf, 102 ®s->regs, 103 0, a0_start); 104 err |= user_regset_copyin(&pos, &count, &kbuf, &ubuf, 105 ®s->orig_a0, 106 a0_start, a0_start + sizeof(u64)); 107 err |= user_regset_copyin(&pos, &count, &kbuf, &ubuf, 108 ®s->csr_era, 109 era_start, era_start + sizeof(u64)); 110 err |= user_regset_copyin(&pos, &count, &kbuf, &ubuf, 111 ®s->csr_badvaddr, 112 badvaddr_start, badvaddr_start + sizeof(u64)); 113 114 return err; 115 } 116 117 118 /* 119 * Get the general floating-point registers. 120 */ 121 static int gfpr_get(struct task_struct *target, struct membuf *to) 122 { 123 return membuf_write(to, &target->thread.fpu.fpr, 124 sizeof(elf_fpreg_t) * NUM_FPU_REGS); 125 } 126 127 static int gfpr_get_simd(struct task_struct *target, struct membuf *to) 128 { 129 int i, r; 130 u64 fpr_val; 131 132 BUILD_BUG_ON(sizeof(fpr_val) != sizeof(elf_fpreg_t)); 133 for (i = 0; i < NUM_FPU_REGS; i++) { 134 fpr_val = get_fpr64(&target->thread.fpu.fpr[i], 0); 135 r = membuf_write(to, &fpr_val, sizeof(elf_fpreg_t)); 136 } 137 138 return r; 139 } 140 141 /* 142 * Choose the appropriate helper for general registers, and then copy 143 * the FCC and FCSR registers separately. 144 */ 145 static int fpr_get(struct task_struct *target, 146 const struct user_regset *regset, 147 struct membuf to) 148 { 149 int r; 150 151 save_fpu_regs(target); 152 153 if (sizeof(target->thread.fpu.fpr[0]) == sizeof(elf_fpreg_t)) 154 r = gfpr_get(target, &to); 155 else 156 r = gfpr_get_simd(target, &to); 157 158 r = membuf_write(&to, &target->thread.fpu.fcc, sizeof(target->thread.fpu.fcc)); 159 r = membuf_write(&to, &target->thread.fpu.fcsr, sizeof(target->thread.fpu.fcsr)); 160 161 return r; 162 } 163 164 static int gfpr_set(struct task_struct *target, 165 unsigned int *pos, unsigned int *count, 166 const void **kbuf, const void __user **ubuf) 167 { 168 return user_regset_copyin(pos, count, kbuf, ubuf, 169 &target->thread.fpu.fpr, 170 0, NUM_FPU_REGS * sizeof(elf_fpreg_t)); 171 } 172 173 static int gfpr_set_simd(struct task_struct *target, 174 unsigned int *pos, unsigned int *count, 175 const void **kbuf, const void __user **ubuf) 176 { 177 int i, err; 178 u64 fpr_val; 179 180 BUILD_BUG_ON(sizeof(fpr_val) != sizeof(elf_fpreg_t)); 181 for (i = 0; i < NUM_FPU_REGS && *count > 0; i++) { 182 err = user_regset_copyin(pos, count, kbuf, ubuf, 183 &fpr_val, i * sizeof(elf_fpreg_t), 184 (i + 1) * sizeof(elf_fpreg_t)); 185 if (err) 186 return err; 187 set_fpr64(&target->thread.fpu.fpr[i], 0, fpr_val); 188 } 189 190 return 0; 191 } 192 193 /* 194 * Choose the appropriate helper for general registers, and then copy 195 * the FCC register separately. 196 */ 197 static int fpr_set(struct task_struct *target, 198 const struct user_regset *regset, 199 unsigned int pos, unsigned int count, 200 const void *kbuf, const void __user *ubuf) 201 { 202 const int fcc_start = NUM_FPU_REGS * sizeof(elf_fpreg_t); 203 const int fcsr_start = fcc_start + sizeof(u64); 204 int err; 205 206 BUG_ON(count % sizeof(elf_fpreg_t)); 207 if (pos + count > sizeof(elf_fpregset_t)) 208 return -EIO; 209 210 init_fp_ctx(target); 211 212 if (sizeof(target->thread.fpu.fpr[0]) == sizeof(elf_fpreg_t)) 213 err = gfpr_set(target, &pos, &count, &kbuf, &ubuf); 214 else 215 err = gfpr_set_simd(target, &pos, &count, &kbuf, &ubuf); 216 if (err) 217 return err; 218 219 err |= user_regset_copyin(&pos, &count, &kbuf, &ubuf, 220 &target->thread.fpu.fcc, fcc_start, 221 fcc_start + sizeof(u64)); 222 err |= user_regset_copyin(&pos, &count, &kbuf, &ubuf, 223 &target->thread.fpu.fcsr, fcsr_start, 224 fcsr_start + sizeof(u32)); 225 226 return err; 227 } 228 229 static int cfg_get(struct task_struct *target, 230 const struct user_regset *regset, 231 struct membuf to) 232 { 233 int i, r; 234 u32 cfg_val; 235 236 i = 0; 237 while (to.left > 0) { 238 cfg_val = read_cpucfg(i++); 239 r = membuf_write(&to, &cfg_val, sizeof(u32)); 240 } 241 242 return r; 243 } 244 245 /* 246 * CFG registers are read-only. 247 */ 248 static int cfg_set(struct task_struct *target, 249 const struct user_regset *regset, 250 unsigned int pos, unsigned int count, 251 const void *kbuf, const void __user *ubuf) 252 { 253 return 0; 254 } 255 256 #ifdef CONFIG_CPU_HAS_LSX 257 258 static void copy_pad_fprs(struct task_struct *target, 259 const struct user_regset *regset, 260 struct membuf *to, unsigned int live_sz) 261 { 262 int i, j; 263 unsigned long long fill = ~0ull; 264 unsigned int cp_sz, pad_sz; 265 266 cp_sz = min(regset->size, live_sz); 267 pad_sz = regset->size - cp_sz; 268 WARN_ON(pad_sz % sizeof(fill)); 269 270 for (i = 0; i < NUM_FPU_REGS; i++) { 271 membuf_write(to, &target->thread.fpu.fpr[i], cp_sz); 272 for (j = 0; j < (pad_sz / sizeof(fill)); j++) { 273 membuf_store(to, fill); 274 } 275 } 276 } 277 278 static int simd_get(struct task_struct *target, 279 const struct user_regset *regset, 280 struct membuf to) 281 { 282 const unsigned int wr_size = NUM_FPU_REGS * regset->size; 283 284 save_fpu_regs(target); 285 286 if (!tsk_used_math(target)) { 287 /* The task hasn't used FP or LSX, fill with 0xff */ 288 copy_pad_fprs(target, regset, &to, 0); 289 } else if (!test_tsk_thread_flag(target, TIF_LSX_CTX_LIVE)) { 290 /* Copy scalar FP context, fill the rest with 0xff */ 291 copy_pad_fprs(target, regset, &to, 8); 292 #ifdef CONFIG_CPU_HAS_LASX 293 } else if (!test_tsk_thread_flag(target, TIF_LASX_CTX_LIVE)) { 294 /* Copy LSX 128 Bit context, fill the rest with 0xff */ 295 copy_pad_fprs(target, regset, &to, 16); 296 #endif 297 } else if (sizeof(target->thread.fpu.fpr[0]) == regset->size) { 298 /* Trivially copy the vector registers */ 299 membuf_write(&to, &target->thread.fpu.fpr, wr_size); 300 } else { 301 /* Copy as much context as possible, fill the rest with 0xff */ 302 copy_pad_fprs(target, regset, &to, sizeof(target->thread.fpu.fpr[0])); 303 } 304 305 return 0; 306 } 307 308 static int simd_set(struct task_struct *target, 309 const struct user_regset *regset, 310 unsigned int pos, unsigned int count, 311 const void *kbuf, const void __user *ubuf) 312 { 313 const unsigned int wr_size = NUM_FPU_REGS * regset->size; 314 unsigned int cp_sz; 315 int i, err, start; 316 317 init_fp_ctx(target); 318 319 if (sizeof(target->thread.fpu.fpr[0]) == regset->size) { 320 /* Trivially copy the vector registers */ 321 err = user_regset_copyin(&pos, &count, &kbuf, &ubuf, 322 &target->thread.fpu.fpr, 323 0, wr_size); 324 } else { 325 /* Copy as much context as possible */ 326 cp_sz = min_t(unsigned int, regset->size, 327 sizeof(target->thread.fpu.fpr[0])); 328 329 i = start = err = 0; 330 for (; i < NUM_FPU_REGS; i++, start += regset->size) { 331 err |= user_regset_copyin(&pos, &count, &kbuf, &ubuf, 332 &target->thread.fpu.fpr[i], 333 start, start + cp_sz); 334 } 335 } 336 337 return err; 338 } 339 340 #endif /* CONFIG_CPU_HAS_LSX */ 341 342 #ifdef CONFIG_CPU_HAS_LBT 343 static int lbt_get(struct task_struct *target, 344 const struct user_regset *regset, 345 struct membuf to) 346 { 347 int r; 348 349 r = membuf_write(&to, &target->thread.lbt.scr0, sizeof(target->thread.lbt.scr0)); 350 r = membuf_write(&to, &target->thread.lbt.scr1, sizeof(target->thread.lbt.scr1)); 351 r = membuf_write(&to, &target->thread.lbt.scr2, sizeof(target->thread.lbt.scr2)); 352 r = membuf_write(&to, &target->thread.lbt.scr3, sizeof(target->thread.lbt.scr3)); 353 r = membuf_write(&to, &target->thread.lbt.eflags, sizeof(u32)); 354 r = membuf_write(&to, &target->thread.fpu.ftop, sizeof(u32)); 355 356 return r; 357 } 358 359 static int lbt_set(struct task_struct *target, 360 const struct user_regset *regset, 361 unsigned int pos, unsigned int count, 362 const void *kbuf, const void __user *ubuf) 363 { 364 int err = 0; 365 const int eflags_start = 4 * sizeof(target->thread.lbt.scr0); 366 const int ftop_start = eflags_start + sizeof(u32); 367 368 err |= user_regset_copyin(&pos, &count, &kbuf, &ubuf, 369 &target->thread.lbt.scr0, 370 0, 4 * sizeof(target->thread.lbt.scr0)); 371 err |= user_regset_copyin(&pos, &count, &kbuf, &ubuf, 372 &target->thread.lbt.eflags, 373 eflags_start, ftop_start); 374 err |= user_regset_copyin(&pos, &count, &kbuf, &ubuf, 375 &target->thread.fpu.ftop, 376 ftop_start, ftop_start + sizeof(u32)); 377 378 return err; 379 } 380 #endif /* CONFIG_CPU_HAS_LBT */ 381 382 #ifdef CONFIG_HAVE_HW_BREAKPOINT 383 384 /* 385 * Handle hitting a HW-breakpoint. 386 */ 387 static void ptrace_hbptriggered(struct perf_event *bp, 388 struct perf_sample_data *data, 389 struct pt_regs *regs) 390 { 391 int i; 392 struct arch_hw_breakpoint *bkpt = counter_arch_bp(bp); 393 394 for (i = 0; i < LOONGARCH_MAX_BRP; ++i) 395 if (current->thread.hbp_break[i] == bp) 396 break; 397 398 for (i = 0; i < LOONGARCH_MAX_WRP; ++i) 399 if (current->thread.hbp_watch[i] == bp) 400 break; 401 402 force_sig_ptrace_errno_trap(i, (void __user *)bkpt->address); 403 } 404 405 static struct perf_event *ptrace_hbp_get_event(unsigned int note_type, 406 struct task_struct *tsk, 407 unsigned long idx) 408 { 409 struct perf_event *bp; 410 411 switch (note_type) { 412 case NT_LOONGARCH_HW_BREAK: 413 if (idx >= LOONGARCH_MAX_BRP) 414 return ERR_PTR(-EINVAL); 415 idx = array_index_nospec(idx, LOONGARCH_MAX_BRP); 416 bp = tsk->thread.hbp_break[idx]; 417 break; 418 case NT_LOONGARCH_HW_WATCH: 419 if (idx >= LOONGARCH_MAX_WRP) 420 return ERR_PTR(-EINVAL); 421 idx = array_index_nospec(idx, LOONGARCH_MAX_WRP); 422 bp = tsk->thread.hbp_watch[idx]; 423 break; 424 } 425 426 return bp; 427 } 428 429 static int ptrace_hbp_set_event(unsigned int note_type, 430 struct task_struct *tsk, 431 unsigned long idx, 432 struct perf_event *bp) 433 { 434 switch (note_type) { 435 case NT_LOONGARCH_HW_BREAK: 436 if (idx >= LOONGARCH_MAX_BRP) 437 return -EINVAL; 438 idx = array_index_nospec(idx, LOONGARCH_MAX_BRP); 439 tsk->thread.hbp_break[idx] = bp; 440 break; 441 case NT_LOONGARCH_HW_WATCH: 442 if (idx >= LOONGARCH_MAX_WRP) 443 return -EINVAL; 444 idx = array_index_nospec(idx, LOONGARCH_MAX_WRP); 445 tsk->thread.hbp_watch[idx] = bp; 446 break; 447 } 448 449 return 0; 450 } 451 452 static struct perf_event *ptrace_hbp_create(unsigned int note_type, 453 struct task_struct *tsk, 454 unsigned long idx) 455 { 456 int err, type; 457 struct perf_event *bp; 458 struct perf_event_attr attr; 459 460 switch (note_type) { 461 case NT_LOONGARCH_HW_BREAK: 462 type = HW_BREAKPOINT_X; 463 break; 464 case NT_LOONGARCH_HW_WATCH: 465 type = HW_BREAKPOINT_RW; 466 break; 467 default: 468 return ERR_PTR(-EINVAL); 469 } 470 471 ptrace_breakpoint_init(&attr); 472 473 /* 474 * Initialise fields to sane defaults 475 * (i.e. values that will pass validation). 476 */ 477 attr.bp_addr = 0; 478 attr.bp_len = HW_BREAKPOINT_LEN_4; 479 attr.bp_type = type; 480 attr.disabled = 1; 481 482 bp = register_user_hw_breakpoint(&attr, ptrace_hbptriggered, NULL, tsk); 483 if (IS_ERR(bp)) 484 return bp; 485 486 err = ptrace_hbp_set_event(note_type, tsk, idx, bp); 487 if (err) 488 return ERR_PTR(err); 489 490 return bp; 491 } 492 493 static int ptrace_hbp_fill_attr_ctrl(unsigned int note_type, 494 struct arch_hw_breakpoint_ctrl ctrl, 495 struct perf_event_attr *attr) 496 { 497 int err, len, type, offset; 498 499 err = arch_bp_generic_fields(ctrl, &len, &type, &offset); 500 if (err) 501 return err; 502 503 switch (note_type) { 504 case NT_LOONGARCH_HW_BREAK: 505 if ((type & HW_BREAKPOINT_X) != type) 506 return -EINVAL; 507 break; 508 case NT_LOONGARCH_HW_WATCH: 509 if ((type & HW_BREAKPOINT_RW) != type) 510 return -EINVAL; 511 break; 512 default: 513 return -EINVAL; 514 } 515 516 attr->bp_len = len; 517 attr->bp_type = type; 518 attr->bp_addr += offset; 519 520 return 0; 521 } 522 523 static int ptrace_hbp_get_resource_info(unsigned int note_type, u64 *info) 524 { 525 u8 num; 526 u64 reg = 0; 527 528 switch (note_type) { 529 case NT_LOONGARCH_HW_BREAK: 530 num = hw_breakpoint_slots(TYPE_INST); 531 break; 532 case NT_LOONGARCH_HW_WATCH: 533 num = hw_breakpoint_slots(TYPE_DATA); 534 break; 535 default: 536 return -EINVAL; 537 } 538 539 *info = reg | num; 540 541 return 0; 542 } 543 544 static struct perf_event *ptrace_hbp_get_initialised_bp(unsigned int note_type, 545 struct task_struct *tsk, 546 unsigned long idx) 547 { 548 struct perf_event *bp = ptrace_hbp_get_event(note_type, tsk, idx); 549 550 if (!bp) 551 bp = ptrace_hbp_create(note_type, tsk, idx); 552 553 return bp; 554 } 555 556 static int ptrace_hbp_get_ctrl(unsigned int note_type, 557 struct task_struct *tsk, 558 unsigned long idx, u32 *ctrl) 559 { 560 struct perf_event *bp = ptrace_hbp_get_event(note_type, tsk, idx); 561 562 if (IS_ERR(bp)) 563 return PTR_ERR(bp); 564 565 *ctrl = bp ? encode_ctrl_reg(counter_arch_bp(bp)->ctrl) : 0; 566 567 return 0; 568 } 569 570 static int ptrace_hbp_get_mask(unsigned int note_type, 571 struct task_struct *tsk, 572 unsigned long idx, u64 *mask) 573 { 574 struct perf_event *bp = ptrace_hbp_get_event(note_type, tsk, idx); 575 576 if (IS_ERR(bp)) 577 return PTR_ERR(bp); 578 579 *mask = bp ? counter_arch_bp(bp)->mask : 0; 580 581 return 0; 582 } 583 584 static int ptrace_hbp_get_addr(unsigned int note_type, 585 struct task_struct *tsk, 586 unsigned long idx, u64 *addr) 587 { 588 struct perf_event *bp = ptrace_hbp_get_event(note_type, tsk, idx); 589 590 if (IS_ERR(bp)) 591 return PTR_ERR(bp); 592 593 *addr = bp ? counter_arch_bp(bp)->address : 0; 594 595 return 0; 596 } 597 598 static int ptrace_hbp_set_ctrl(unsigned int note_type, 599 struct task_struct *tsk, 600 unsigned long idx, u32 uctrl) 601 { 602 int err; 603 struct perf_event *bp; 604 struct perf_event_attr attr; 605 struct arch_hw_breakpoint_ctrl ctrl; 606 607 bp = ptrace_hbp_get_initialised_bp(note_type, tsk, idx); 608 if (IS_ERR(bp)) 609 return PTR_ERR(bp); 610 611 attr = bp->attr; 612 decode_ctrl_reg(uctrl, &ctrl); 613 err = ptrace_hbp_fill_attr_ctrl(note_type, ctrl, &attr); 614 if (err) 615 return err; 616 617 return modify_user_hw_breakpoint(bp, &attr); 618 } 619 620 static int ptrace_hbp_set_mask(unsigned int note_type, 621 struct task_struct *tsk, 622 unsigned long idx, u64 mask) 623 { 624 struct perf_event *bp; 625 struct perf_event_attr attr; 626 struct arch_hw_breakpoint *info; 627 628 bp = ptrace_hbp_get_initialised_bp(note_type, tsk, idx); 629 if (IS_ERR(bp)) 630 return PTR_ERR(bp); 631 632 attr = bp->attr; 633 info = counter_arch_bp(bp); 634 info->mask = mask; 635 636 return modify_user_hw_breakpoint(bp, &attr); 637 } 638 639 static int ptrace_hbp_set_addr(unsigned int note_type, 640 struct task_struct *tsk, 641 unsigned long idx, u64 addr) 642 { 643 struct perf_event *bp; 644 struct perf_event_attr attr; 645 646 bp = ptrace_hbp_get_initialised_bp(note_type, tsk, idx); 647 if (IS_ERR(bp)) 648 return PTR_ERR(bp); 649 650 attr = bp->attr; 651 attr.bp_addr = addr; 652 653 return modify_user_hw_breakpoint(bp, &attr); 654 } 655 656 #define PTRACE_HBP_ADDR_SZ sizeof(u64) 657 #define PTRACE_HBP_MASK_SZ sizeof(u64) 658 #define PTRACE_HBP_CTRL_SZ sizeof(u32) 659 #define PTRACE_HBP_PAD_SZ sizeof(u32) 660 661 static int hw_break_get(struct task_struct *target, 662 const struct user_regset *regset, 663 struct membuf to) 664 { 665 u64 info; 666 u32 ctrl; 667 u64 addr, mask; 668 int ret, idx = 0; 669 unsigned int note_type = regset->core_note_type; 670 671 /* Resource info */ 672 ret = ptrace_hbp_get_resource_info(note_type, &info); 673 if (ret) 674 return ret; 675 676 membuf_write(&to, &info, sizeof(info)); 677 678 /* (address, mask, ctrl) registers */ 679 while (to.left) { 680 ret = ptrace_hbp_get_addr(note_type, target, idx, &addr); 681 if (ret) 682 return ret; 683 684 ret = ptrace_hbp_get_mask(note_type, target, idx, &mask); 685 if (ret) 686 return ret; 687 688 ret = ptrace_hbp_get_ctrl(note_type, target, idx, &ctrl); 689 if (ret) 690 return ret; 691 692 membuf_store(&to, addr); 693 membuf_store(&to, mask); 694 membuf_store(&to, ctrl); 695 membuf_zero(&to, sizeof(u32)); 696 idx++; 697 } 698 699 return 0; 700 } 701 702 static int hw_break_set(struct task_struct *target, 703 const struct user_regset *regset, 704 unsigned int pos, unsigned int count, 705 const void *kbuf, const void __user *ubuf) 706 { 707 u32 ctrl; 708 u64 addr, mask; 709 int ret, idx = 0, offset, limit; 710 unsigned int note_type = regset->core_note_type; 711 712 /* Resource info */ 713 offset = offsetof(struct user_watch_state, dbg_regs); 714 user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf, 0, offset); 715 716 /* (address, mask, ctrl) registers */ 717 limit = regset->n * regset->size; 718 while (count && offset < limit) { 719 if (count < PTRACE_HBP_ADDR_SZ) 720 return -EINVAL; 721 722 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &addr, 723 offset, offset + PTRACE_HBP_ADDR_SZ); 724 if (ret) 725 return ret; 726 727 ret = ptrace_hbp_set_addr(note_type, target, idx, addr); 728 if (ret) 729 return ret; 730 offset += PTRACE_HBP_ADDR_SZ; 731 732 if (!count) 733 break; 734 735 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &mask, 736 offset, offset + PTRACE_HBP_MASK_SZ); 737 if (ret) 738 return ret; 739 740 ret = ptrace_hbp_set_mask(note_type, target, idx, mask); 741 if (ret) 742 return ret; 743 offset += PTRACE_HBP_MASK_SZ; 744 745 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &ctrl, 746 offset, offset + PTRACE_HBP_CTRL_SZ); 747 if (ret) 748 return ret; 749 750 ret = ptrace_hbp_set_ctrl(note_type, target, idx, ctrl); 751 if (ret) 752 return ret; 753 offset += PTRACE_HBP_CTRL_SZ; 754 755 user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf, 756 offset, offset + PTRACE_HBP_PAD_SZ); 757 offset += PTRACE_HBP_PAD_SZ; 758 759 idx++; 760 } 761 762 return 0; 763 } 764 765 #endif 766 767 struct pt_regs_offset { 768 const char *name; 769 int offset; 770 }; 771 772 #define REG_OFFSET_NAME(n, r) {.name = #n, .offset = offsetof(struct pt_regs, r)} 773 #define REG_OFFSET_END {.name = NULL, .offset = 0} 774 775 static const struct pt_regs_offset regoffset_table[] = { 776 REG_OFFSET_NAME(r0, regs[0]), 777 REG_OFFSET_NAME(r1, regs[1]), 778 REG_OFFSET_NAME(r2, regs[2]), 779 REG_OFFSET_NAME(r3, regs[3]), 780 REG_OFFSET_NAME(r4, regs[4]), 781 REG_OFFSET_NAME(r5, regs[5]), 782 REG_OFFSET_NAME(r6, regs[6]), 783 REG_OFFSET_NAME(r7, regs[7]), 784 REG_OFFSET_NAME(r8, regs[8]), 785 REG_OFFSET_NAME(r9, regs[9]), 786 REG_OFFSET_NAME(r10, regs[10]), 787 REG_OFFSET_NAME(r11, regs[11]), 788 REG_OFFSET_NAME(r12, regs[12]), 789 REG_OFFSET_NAME(r13, regs[13]), 790 REG_OFFSET_NAME(r14, regs[14]), 791 REG_OFFSET_NAME(r15, regs[15]), 792 REG_OFFSET_NAME(r16, regs[16]), 793 REG_OFFSET_NAME(r17, regs[17]), 794 REG_OFFSET_NAME(r18, regs[18]), 795 REG_OFFSET_NAME(r19, regs[19]), 796 REG_OFFSET_NAME(r20, regs[20]), 797 REG_OFFSET_NAME(r21, regs[21]), 798 REG_OFFSET_NAME(r22, regs[22]), 799 REG_OFFSET_NAME(r23, regs[23]), 800 REG_OFFSET_NAME(r24, regs[24]), 801 REG_OFFSET_NAME(r25, regs[25]), 802 REG_OFFSET_NAME(r26, regs[26]), 803 REG_OFFSET_NAME(r27, regs[27]), 804 REG_OFFSET_NAME(r28, regs[28]), 805 REG_OFFSET_NAME(r29, regs[29]), 806 REG_OFFSET_NAME(r30, regs[30]), 807 REG_OFFSET_NAME(r31, regs[31]), 808 REG_OFFSET_NAME(orig_a0, orig_a0), 809 REG_OFFSET_NAME(csr_era, csr_era), 810 REG_OFFSET_NAME(csr_badvaddr, csr_badvaddr), 811 REG_OFFSET_NAME(csr_crmd, csr_crmd), 812 REG_OFFSET_NAME(csr_prmd, csr_prmd), 813 REG_OFFSET_NAME(csr_euen, csr_euen), 814 REG_OFFSET_NAME(csr_ecfg, csr_ecfg), 815 REG_OFFSET_NAME(csr_estat, csr_estat), 816 REG_OFFSET_END, 817 }; 818 819 /** 820 * regs_query_register_offset() - query register offset from its name 821 * @name: the name of a register 822 * 823 * regs_query_register_offset() returns the offset of a register in struct 824 * pt_regs from its name. If the name is invalid, this returns -EINVAL; 825 */ 826 int regs_query_register_offset(const char *name) 827 { 828 const struct pt_regs_offset *roff; 829 830 for (roff = regoffset_table; roff->name != NULL; roff++) 831 if (!strcmp(roff->name, name)) 832 return roff->offset; 833 return -EINVAL; 834 } 835 836 enum loongarch_regset { 837 REGSET_GPR, 838 REGSET_FPR, 839 REGSET_CPUCFG, 840 #ifdef CONFIG_CPU_HAS_LSX 841 REGSET_LSX, 842 #endif 843 #ifdef CONFIG_CPU_HAS_LASX 844 REGSET_LASX, 845 #endif 846 #ifdef CONFIG_CPU_HAS_LBT 847 REGSET_LBT, 848 #endif 849 #ifdef CONFIG_HAVE_HW_BREAKPOINT 850 REGSET_HW_BREAK, 851 REGSET_HW_WATCH, 852 #endif 853 }; 854 855 static const struct user_regset loongarch64_regsets[] = { 856 [REGSET_GPR] = { 857 .core_note_type = NT_PRSTATUS, 858 .n = ELF_NGREG, 859 .size = sizeof(elf_greg_t), 860 .align = sizeof(elf_greg_t), 861 .regset_get = gpr_get, 862 .set = gpr_set, 863 }, 864 [REGSET_FPR] = { 865 .core_note_type = NT_PRFPREG, 866 .n = ELF_NFPREG, 867 .size = sizeof(elf_fpreg_t), 868 .align = sizeof(elf_fpreg_t), 869 .regset_get = fpr_get, 870 .set = fpr_set, 871 }, 872 [REGSET_CPUCFG] = { 873 .core_note_type = NT_LOONGARCH_CPUCFG, 874 .n = 64, 875 .size = sizeof(u32), 876 .align = sizeof(u32), 877 .regset_get = cfg_get, 878 .set = cfg_set, 879 }, 880 #ifdef CONFIG_CPU_HAS_LSX 881 [REGSET_LSX] = { 882 .core_note_type = NT_LOONGARCH_LSX, 883 .n = NUM_FPU_REGS, 884 .size = 16, 885 .align = 16, 886 .regset_get = simd_get, 887 .set = simd_set, 888 }, 889 #endif 890 #ifdef CONFIG_CPU_HAS_LASX 891 [REGSET_LASX] = { 892 .core_note_type = NT_LOONGARCH_LASX, 893 .n = NUM_FPU_REGS, 894 .size = 32, 895 .align = 32, 896 .regset_get = simd_get, 897 .set = simd_set, 898 }, 899 #endif 900 #ifdef CONFIG_CPU_HAS_LBT 901 [REGSET_LBT] = { 902 .core_note_type = NT_LOONGARCH_LBT, 903 .n = 5, 904 .size = sizeof(u64), 905 .align = sizeof(u64), 906 .regset_get = lbt_get, 907 .set = lbt_set, 908 }, 909 #endif 910 #ifdef CONFIG_HAVE_HW_BREAKPOINT 911 [REGSET_HW_BREAK] = { 912 .core_note_type = NT_LOONGARCH_HW_BREAK, 913 .n = sizeof(struct user_watch_state) / sizeof(u32), 914 .size = sizeof(u32), 915 .align = sizeof(u32), 916 .regset_get = hw_break_get, 917 .set = hw_break_set, 918 }, 919 [REGSET_HW_WATCH] = { 920 .core_note_type = NT_LOONGARCH_HW_WATCH, 921 .n = sizeof(struct user_watch_state) / sizeof(u32), 922 .size = sizeof(u32), 923 .align = sizeof(u32), 924 .regset_get = hw_break_get, 925 .set = hw_break_set, 926 }, 927 #endif 928 }; 929 930 static const struct user_regset_view user_loongarch64_view = { 931 .name = "loongarch64", 932 .e_machine = ELF_ARCH, 933 .regsets = loongarch64_regsets, 934 .n = ARRAY_SIZE(loongarch64_regsets), 935 }; 936 937 938 const struct user_regset_view *task_user_regset_view(struct task_struct *task) 939 { 940 return &user_loongarch64_view; 941 } 942 943 static inline int read_user(struct task_struct *target, unsigned long addr, 944 unsigned long __user *data) 945 { 946 unsigned long tmp = 0; 947 948 switch (addr) { 949 case 0 ... 31: 950 tmp = task_pt_regs(target)->regs[addr]; 951 break; 952 case ARG0: 953 tmp = task_pt_regs(target)->orig_a0; 954 break; 955 case PC: 956 tmp = task_pt_regs(target)->csr_era; 957 break; 958 case BADVADDR: 959 tmp = task_pt_regs(target)->csr_badvaddr; 960 break; 961 default: 962 return -EIO; 963 } 964 965 return put_user(tmp, data); 966 } 967 968 static inline int write_user(struct task_struct *target, unsigned long addr, 969 unsigned long data) 970 { 971 switch (addr) { 972 case 0 ... 31: 973 task_pt_regs(target)->regs[addr] = data; 974 break; 975 case ARG0: 976 task_pt_regs(target)->orig_a0 = data; 977 break; 978 case PC: 979 task_pt_regs(target)->csr_era = data; 980 break; 981 case BADVADDR: 982 task_pt_regs(target)->csr_badvaddr = data; 983 break; 984 default: 985 return -EIO; 986 } 987 988 return 0; 989 } 990 991 long arch_ptrace(struct task_struct *child, long request, 992 unsigned long addr, unsigned long data) 993 { 994 int ret; 995 unsigned long __user *datap = (void __user *) data; 996 997 switch (request) { 998 case PTRACE_PEEKUSR: 999 ret = read_user(child, addr, datap); 1000 break; 1001 1002 case PTRACE_POKEUSR: 1003 ret = write_user(child, addr, data); 1004 break; 1005 1006 default: 1007 ret = ptrace_request(child, request, addr, data); 1008 break; 1009 } 1010 1011 return ret; 1012 } 1013 1014 #ifdef CONFIG_HAVE_HW_BREAKPOINT 1015 static void ptrace_triggered(struct perf_event *bp, 1016 struct perf_sample_data *data, struct pt_regs *regs) 1017 { 1018 struct perf_event_attr attr; 1019 1020 attr = bp->attr; 1021 attr.disabled = true; 1022 modify_user_hw_breakpoint(bp, &attr); 1023 } 1024 1025 static int set_single_step(struct task_struct *tsk, unsigned long addr) 1026 { 1027 struct perf_event *bp; 1028 struct perf_event_attr attr; 1029 struct arch_hw_breakpoint *info; 1030 struct thread_struct *thread = &tsk->thread; 1031 1032 bp = thread->hbp_break[0]; 1033 if (!bp) { 1034 ptrace_breakpoint_init(&attr); 1035 1036 attr.bp_addr = addr; 1037 attr.bp_len = HW_BREAKPOINT_LEN_8; 1038 attr.bp_type = HW_BREAKPOINT_X; 1039 1040 bp = register_user_hw_breakpoint(&attr, ptrace_triggered, 1041 NULL, tsk); 1042 if (IS_ERR(bp)) 1043 return PTR_ERR(bp); 1044 1045 thread->hbp_break[0] = bp; 1046 } else { 1047 int err; 1048 1049 attr = bp->attr; 1050 attr.bp_addr = addr; 1051 1052 /* Reenable breakpoint */ 1053 attr.disabled = false; 1054 err = modify_user_hw_breakpoint(bp, &attr); 1055 if (unlikely(err)) 1056 return err; 1057 1058 csr_write64(attr.bp_addr, LOONGARCH_CSR_IB0ADDR); 1059 } 1060 info = counter_arch_bp(bp); 1061 info->mask = TASK_SIZE - 1; 1062 1063 return 0; 1064 } 1065 1066 /* ptrace API */ 1067 void user_enable_single_step(struct task_struct *task) 1068 { 1069 struct thread_info *ti = task_thread_info(task); 1070 1071 set_single_step(task, task_pt_regs(task)->csr_era); 1072 task->thread.single_step = task_pt_regs(task)->csr_era; 1073 set_ti_thread_flag(ti, TIF_SINGLESTEP); 1074 } 1075 1076 void user_disable_single_step(struct task_struct *task) 1077 { 1078 clear_tsk_thread_flag(task, TIF_SINGLESTEP); 1079 } 1080 #endif 1081