arch/sparc/kernel/unaligned_64.c

   1 /*
   2  * unaligned.c: Unaligned load/store trap handling with special
   3  *              cases for the kernel to do them more quickly.
   4  *
   5  * Copyright (C) 1996,2008 David S. Miller (davem@davemloft.net)
   6  * Copyright (C) 1996,1997 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
   7  */
   8
   9
  10 #include <linux/jiffies.h>
  11 #include <linux/kernel.h>
  12 #include <linux/sched.h>
  13 #include <linux/mm.h>
  14 #include <linux/module.h>
  15 #include <asm/asi.h>
  16 #include <asm/ptrace.h>
  17 #include <asm/pstate.h>
  18 #include <asm/processor.h>
  19 #include <asm/system.h>
  20 #include <asm/uaccess.h>
  21 #include <linux/smp.h>
  22 #include <linux/bitops.h>
  23 #include <linux/perf_event.h>
  24 #include <linux/ratelimit.h>
  25 #include <linux/bitops.h>
  26 #include <asm/fpumacro.h>
  27
  28 enum direction {
  29         load,    /* ld, ldd, ldh, ldsh */
  30         store,   /* st, std, sth, stsh */
  31         both,    /* Swap, ldstub, cas, ... */
  32         fpld,
  33         fpst,
  34         invalid,
  35 };
  36
  37 static inline enum direction decode_direction(unsigned int insn)
  38 {
  39         unsigned long tmp = (insn >> 21) & 1;
  40
  41         if (!tmp)
  42                 return load;
  43         else {
  44                 switch ((insn>>19)&0xf) {
  45                 case 15: /* swap* */
  46                         return both;
  47                 default:
  48                         return store;
  49                 }
  50         }
  51 }
  52
  53 /* 16 = double-word, 8 = extra-word, 4 = word, 2 = half-word */
  54 static inline int decode_access_size(struct pt_regs *regs, unsigned int insn)
  55 {
  56         unsigned int tmp;
  57
  58         tmp = ((insn >> 19) & 0xf);
  59         if (tmp == 11 || tmp == 14) /* ldx/stx */
  60                 return 8;
  61         tmp &= 3;
  62         if (!tmp)
  63                 return 4;
  64         else if (tmp == 3)
  65                 return 16;      /* ldd/std - Although it is actually 8 */
  66         else if (tmp == 2)
  67                 return 2;
  68         else {
  69                 printk("Impossible unaligned trap. insn=%08x\n", insn);
  70                 die_if_kernel("Byte sized unaligned access?!?!", regs);
  71
  72                 /* GCC should never warn that control reaches the end
  73                  * of this function without returning a value because
  74                  * die_if_kernel() is marked with attribute 'noreturn'.
  75                  * Alas, some versions do...
  76                  */
  77
  78                 return 0;
  79         }
  80 }
  81
  82 static inline int decode_asi(unsigned int insn, struct pt_regs *regs)
  83 {
  84         if (insn & 0x800000) {
  85                 if (insn & 0x2000)
  86                         return (unsigned char)(regs->tstate >> 24);     /* %asi */
  87                 else
  88                         return (unsigned char)(insn >> 5);              /* imm_asi */
  89         } else
  90                 return ASI_P;
  91 }
  92
  93 /* 0x400000 = signed, 0 = unsigned */
  94 static inline int decode_signedness(unsigned int insn)
  95 {
  96         return (insn & 0x400000);
  97 }
  98
  99 static inline void maybe_flush_windows(unsigned int rs1, unsigned int rs2,
 100                                        unsigned int rd, int from_kernel)
 101 {
 102         if (rs2 >= 16 || rs1 >= 16 || rd >= 16) {
 103                 if (from_kernel != 0)
 104                         __asm__ __volatile__("flushw");
 105                 else
 106                         flushw_user();
 107         }
 108 }
 109
 110 static inline long sign_extend_imm13(long imm)
 111 {
 112         return imm << 51 >> 51;
 113 }
 114
 115 static unsigned long fetch_reg(unsigned int reg, struct pt_regs *regs)
 116 {
 117         unsigned long value;
 118
 119         if (reg < 16)
 120                 return (!reg ? 0 : regs->u_regs[reg]);
 121         if (regs->tstate & TSTATE_PRIV) {
 122                 struct reg_window *win;
 123                 win = (struct reg_window *)(regs->u_regs[UREG_FP] + STACK_BIAS);
 124                 value = win->locals[reg - 16];
 125         } else if (test_thread_flag(TIF_32BIT)) {
 126                 struct reg_window32 __user *win32;
 127                 win32 = (struct reg_window32 __user *)((unsigned long)((u32)regs->u_regs[UREG_FP]));
 128                 get_user(value, &win32->locals[reg - 16]);
 129         } else {
 130                 struct reg_window __user *win;
 131                 win = (struct reg_window __user *)(regs->u_regs[UREG_FP] + STACK_BIAS);
 132                 get_user(value, &win->locals[reg - 16]);
 133         }
 134         return value;
 135 }
 136
 137 static unsigned long *fetch_reg_addr(unsigned int reg, struct pt_regs *regs)
 138 {
 139         if (reg < 16)
 140                 return &regs->u_regs[reg];
 141         if (regs->tstate & TSTATE_PRIV) {
 142                 struct reg_window *win;
 143                 win = (struct reg_window *)(regs->u_regs[UREG_FP] + STACK_BIAS);
 144                 return &win->locals[reg - 16];
 145         } else if (test_thread_flag(TIF_32BIT)) {
 146                 struct reg_window32 *win32;
 147                 win32 = (struct reg_window32 *)((unsigned long)((u32)regs->u_regs[UREG_FP]));
 148                 return (unsigned long *)&win32->locals[reg - 16];
 149         } else {
 150                 struct reg_window *win;
 151                 win = (struct reg_window *)(regs->u_regs[UREG_FP] + STACK_BIAS);
 152                 return &win->locals[reg - 16];
 153         }
 154 }
 155
 156 unsigned long compute_effective_address(struct pt_regs *regs,
 157                                         unsigned int insn, unsigned int rd)
 158 {
 159         int from_kernel = (regs->tstate & TSTATE_PRIV) != 0;
 160         unsigned int rs1 = (insn >> 14) & 0x1f;
 161         unsigned int rs2 = insn & 0x1f;
 162         unsigned long addr;
 163
 164         if (insn & 0x2000) {
 165                 maybe_flush_windows(rs1, 0, rd, from_kernel);
 166                 addr = (fetch_reg(rs1, regs) + sign_extend_imm13(insn));
 167         } else {
 168                 maybe_flush_windows(rs1, rs2, rd, from_kernel);
 169                 addr = (fetch_reg(rs1, regs) + fetch_reg(rs2, regs));
 170         }
 171
 172         if (!from_kernel && test_thread_flag(TIF_32BIT))
 173                 addr &= 0xffffffff;
 174
 175         return addr;
 176 }
 177
 178 /* This is just to make gcc think die_if_kernel does return... */
 179 static void __used unaligned_panic(char *str, struct pt_regs *regs)
 180 {
 181         die_if_kernel(str, regs);
 182 }
 183
 184 extern int do_int_load(unsigned long *dest_reg, int size,
 185                        unsigned long *saddr, int is_signed, int asi);
 186
 187 extern int __do_int_store(unsigned long *dst_addr, int size,
 188                           unsigned long src_val, int asi);
 189
 190 static inline int do_int_store(int reg_num, int size, unsigned long *dst_addr,
 191                                struct pt_regs *regs, int asi, int orig_asi)
 192 {
 193         unsigned long zero = 0;
 194         unsigned long *src_val_p = &zero;
 195         unsigned long src_val;
 196
 197         if (size == 16) {
 198                 size = 8;
 199                 zero = (((long)(reg_num ?
 200                         (unsigned)fetch_reg(reg_num, regs) : 0)) << 32) |
 201                         (unsigned)fetch_reg(reg_num + 1, regs);
 202         } else if (reg_num) {
 203                 src_val_p = fetch_reg_addr(reg_num, regs);
 204         }
 205         src_val = *src_val_p;
 206         if (unlikely(asi != orig_asi)) {
 207                 switch (size) {
 208                 case 2:
 209                         src_val = swab16(src_val);
 210                         break;
 211                 case 4:
 212                         src_val = swab32(src_val);
 213                         break;
 214                 case 8:
 215                         src_val = swab64(src_val);
 216                         break;
 217                 case 16:
 218                 default:
 219                         BUG();
 220                         break;
 221                 }
 222         }
 223         return __do_int_store(dst_addr, size, src_val, asi);
 224 }
 225
 226 static inline void advance(struct pt_regs *regs)
 227 {
 228         regs->tpc   = regs->tnpc;
 229         regs->tnpc += 4;
 230         if (test_thread_flag(TIF_32BIT)) {
 231                 regs->tpc &= 0xffffffff;
 232                 regs->tnpc &= 0xffffffff;
 233         }
 234 }
 235
 236 static inline int floating_point_load_or_store_p(unsigned int insn)
 237 {
 238         return (insn >> 24) & 1;
 239 }
 240
 241 static inline int ok_for_kernel(unsigned int insn)
 242 {
 243         return !floating_point_load_or_store_p(insn);
 244 }
 245
 246 static void kernel_mna_trap_fault(int fixup_tstate_asi)
 247 {
 248         struct pt_regs *regs = current_thread_info()->kern_una_regs;
 249         unsigned int insn = current_thread_info()->kern_una_insn;
 250         const struct exception_table_entry *entry;
 251
 252         entry = search_exception_tables(regs->tpc);
 253         if (!entry) {
 254                 unsigned long address;
 255
 256                 address = compute_effective_address(regs, insn,
 257                                                     ((insn >> 25) & 0x1f));
 258                 if (address < PAGE_SIZE) {
 259                         printk(KERN_ALERT "Unable to handle kernel NULL "
 260                                "pointer dereference in mna handler");
 261                 } else
 262                         printk(KERN_ALERT "Unable to handle kernel paging "
 263                                "request in mna handler");
 264                 printk(KERN_ALERT " at virtual address %016lx\n",address);
 265                 printk(KERN_ALERT "current->{active_,}mm->context = %016lx\n",
 266                         (current->mm ? CTX_HWBITS(current->mm->context) :
 267                         CTX_HWBITS(current->active_mm->context)));
 268                 printk(KERN_ALERT "current->{active_,}mm->pgd = %016lx\n",
 269                         (current->mm ? (unsigned long) current->mm->pgd :
 270                         (unsigned long) current->active_mm->pgd));
 271                 die_if_kernel("Oops", regs);
 272                 /* Not reached */
 273         }
 274         regs->tpc = entry->fixup;
 275         regs->tnpc = regs->tpc + 4;
 276
 277         if (fixup_tstate_asi) {
 278                 regs->tstate &= ~TSTATE_ASI;
 279                 regs->tstate |= (ASI_AIUS << 24UL);
 280         }
 281 }
 282
 283 static void log_unaligned(struct pt_regs *regs)
 284 {
 285         static DEFINE_RATELIMIT_STATE(ratelimit, 5 * HZ, 5);
 286
 287         if (__ratelimit(&ratelimit)) {
 288                 printk("Kernel unaligned access at TPC[%lx] %pS\n",
 289                        regs->tpc, (void *) regs->tpc);
 290         }
 291 }
 292
 293 asmlinkage void kernel_unaligned_trap(struct pt_regs *regs, unsigned int insn)
 294 {
 295         enum direction dir = decode_direction(insn);
 296         int size = decode_access_size(regs, insn);
 297         int orig_asi, asi;
 298
 299         current_thread_info()->kern_una_regs = regs;
 300         current_thread_info()->kern_una_insn = insn;
 301
 302         orig_asi = asi = decode_asi(insn, regs);
 303
 304         /* If this is a {get,put}_user() on an unaligned userspace pointer,
 305          * just signal a fault and do not log the event.
 306          */
 307         if (asi == ASI_AIUS) {
 308                 kernel_mna_trap_fault(0);
 309                 return;
 310         }
 311
 312         log_unaligned(regs);
 313
 314         if (!ok_for_kernel(insn) || dir == both) {
 315                 printk("Unsupported unaligned load/store trap for kernel "
 316                        "at <%016lx>.\n", regs->tpc);
 317                 unaligned_panic("Kernel does fpu/atomic "
 318                                 "unaligned load/store.", regs);
 319
 320                 kernel_mna_trap_fault(0);
 321         } else {
 322                 unsigned long addr, *reg_addr;
 323                 int err;
 324
 325                 addr = compute_effective_address(regs, insn,
 326                                                  ((insn >> 25) & 0x1f));
 327                 perf_sw_event(PERF_COUNT_SW_ALIGNMENT_FAULTS, 1, regs, addr);
 328                 switch (asi) {
 329                 case ASI_NL:
 330                 case ASI_AIUPL:
 331                 case ASI_AIUSL:
 332                 case ASI_PL:
 333                 case ASI_SL:
 334                 case ASI_PNFL:
 335                 case ASI_SNFL:
 336                         asi &= ~0x08;
 337                         break;
 338                 }
 339                 switch (dir) {
 340                 case load:
 341                         reg_addr = fetch_reg_addr(((insn>>25)&0x1f), regs);
 342                         err = do_int_load(reg_addr, size,
 343                                           (unsigned long *) addr,
 344                                           decode_signedness(insn), asi);
 345                         if (likely(!err) && unlikely(asi != orig_asi)) {
 346                                 unsigned long val_in = *reg_addr;
 347                                 switch (size) {
 348                                 case 2:
 349                                         val_in = swab16(val_in);
 350                                         break;
 351                                 case 4:
 352                                         val_in = swab32(val_in);
 353                                         break;
 354                                 case 8:
 355                                         val_in = swab64(val_in);
 356                                         break;
 357                                 case 16:
 358                                 default:
 359                                         BUG();
 360                                         break;
 361                                 }
 362                                 *reg_addr = val_in;
 363                         }
 364                         break;
 365
 366                 case store:
 367                         err = do_int_store(((insn>>25)&0x1f), size,
 368                                            (unsigned long *) addr, regs,
 369                                            asi, orig_asi);
 370                         break;
 371
 372                 default:
 373                         panic("Impossible kernel unaligned trap.");
 374                         /* Not reached... */
 375                 }
 376                 if (unlikely(err))
 377                         kernel_mna_trap_fault(1);
 378                 else
 379                         advance(regs);
 380         }
 381 }
 382
 383 int handle_popc(u32 insn, struct pt_regs *regs)
 384 {
 385         int from_kernel = (regs->tstate & TSTATE_PRIV) != 0;
 386         int ret, rd = ((insn >> 25) & 0x1f);
 387         u64 value;
 388
 389         perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS, 1, regs, 0);
 390         if (insn & 0x2000) {
 391                 maybe_flush_windows(0, 0, rd, from_kernel);
 392                 value = sign_extend_imm13(insn);
 393         } else {
 394                 maybe_flush_windows(0, insn & 0x1f, rd, from_kernel);
 395                 value = fetch_reg(insn & 0x1f, regs);
 396         }
 397         ret = hweight64(value);
 398         if (rd < 16) {
 399                 if (rd)
 400                         regs->u_regs[rd] = ret;
 401         } else {
 402                 if (test_thread_flag(TIF_32BIT)) {
 403                         struct reg_window32 __user *win32;
 404                         win32 = (struct reg_window32 __user *)((unsigned long)((u32)regs->u_regs[UREG_FP]));
 405                         put_user(ret, &win32->locals[rd - 16]);
 406                 } else {
 407                         struct reg_window __user *win;
 408                         win = (struct reg_window __user *)(regs->u_regs[UREG_FP] + STACK_BIAS);
 409                         put_user(ret, &win->locals[rd - 16]);
 410                 }
 411         }
 412         advance(regs);
 413         return 1;
 414 }
 415
 416 extern void do_fpother(struct pt_regs *regs);
 417 extern void do_privact(struct pt_regs *regs);
 418 extern void spitfire_data_access_exception(struct pt_regs *regs,
 419                                            unsigned long sfsr,
 420                                            unsigned long sfar);
 421 extern void sun4v_data_access_exception(struct pt_regs *regs,
 422                                         unsigned long addr,
 423                                         unsigned long type_ctx);
 424
 425 int handle_ldf_stq(u32 insn, struct pt_regs *regs)
 426 {
 427         unsigned long addr = compute_effective_address(regs, insn, 0);
 428         int freg = ((insn >> 25) & 0x1e) | ((insn >> 20) & 0x20);
 429         struct fpustate *f = FPUSTATE;
 430         int asi = decode_asi(insn, regs);
 431         int flag = (freg < 32) ? FPRS_DL : FPRS_DU;
 432
 433         perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS, 1, regs, 0);
 434
 435         save_and_clear_fpu();
 436         current_thread_info()->xfsr[0] &= ~0x1c000;
 437         if (freg & 3) {
 438                 current_thread_info()->xfsr[0] |= (6 << 14) /* invalid_fp_register */;
 439                 do_fpother(regs);
 440                 return 0;
 441         }
 442         if (insn & 0x200000) {
 443                 /* STQ */
 444                 u64 first = 0, second = 0;
 445
 446                 if (current_thread_info()->fpsaved[0] & flag) {
 447                         first = *(u64 *)&f->regs[freg];
 448                         second = *(u64 *)&f->regs[freg+2];
 449                 }
 450                 if (asi < 0x80) {
 451                         do_privact(regs);
 452                         return 1;
 453                 }
 454                 switch (asi) {
 455                 case ASI_P:
 456                 case ASI_S: break;
 457                 case ASI_PL:
 458                 case ASI_SL:
 459                         {
 460                                 /* Need to convert endians */
 461                                 u64 tmp = __swab64p(&first);
 462
 463                                 first = __swab64p(&second);
 464                                 second = tmp;
 465                                 break;
 466                         }
 467                 default:
 468                         if (tlb_type == hypervisor)
 469                                 sun4v_data_access_exception(regs, addr, 0);
 470                         else
 471                                 spitfire_data_access_exception(regs, 0, addr);
 472                         return 1;
 473                 }
 474                 if (put_user (first >> 32, (u32 __user *)addr) ||
 475                     __put_user ((u32)first, (u32 __user *)(addr + 4)) ||
 476                     __put_user (second >> 32, (u32 __user *)(addr + 8)) ||
 477                     __put_user ((u32)second, (u32 __user *)(addr + 12))) {
 478                         if (tlb_type == hypervisor)
 479                                 sun4v_data_access_exception(regs, addr, 0);
 480                         else
 481                                 spitfire_data_access_exception(regs, 0, addr);
 482                         return 1;
 483                 }
 484         } else {
 485                 /* LDF, LDDF, LDQF */
 486                 u32 data[4] __attribute__ ((aligned(8)));
 487                 int size, i;
 488                 int err;
 489
 490                 if (asi < 0x80) {
 491                         do_privact(regs);
 492                         return 1;
 493                 } else if (asi > ASI_SNFL) {
 494                         if (tlb_type == hypervisor)
 495                                 sun4v_data_access_exception(regs, addr, 0);
 496                         else
 497                                 spitfire_data_access_exception(regs, 0, addr);
 498                         return 1;
 499                 }
 500                 switch (insn & 0x180000) {
 501                 case 0x000000: size = 1; break;
 502                 case 0x100000: size = 4; break;
 503                 default: size = 2; break;
 504                 }
 505                 for (i = 0; i < size; i++)
 506                         data[i] = 0;
 507
 508                 err = get_user (data[0], (u32 __user *) addr);
 509                 if (!err) {
 510                         for (i = 1; i < size; i++)
 511                                 err |= __get_user (data[i], (u32 __user *)(addr + 4*i));
 512                 }
 513                 if (err && !(asi & 0x2 /* NF */)) {
 514                         if (tlb_type == hypervisor)
 515                                 sun4v_data_access_exception(regs, addr, 0);
 516                         else
 517                                 spitfire_data_access_exception(regs, 0, addr);
 518                         return 1;
 519                 }
 520                 if (asi & 0x8) /* Little */ {
 521                         u64 tmp;
 522
 523                         switch (size) {
 524                         case 1: data[0] = le32_to_cpup(data + 0); break;
 525                         default:*(u64 *)(data + 0) = le64_to_cpup((u64 *)(data + 0));
 526                                 break;
 527                         case 4: tmp = le64_to_cpup((u64 *)(data + 0));
 528                                 *(u64 *)(data + 0) = le64_to_cpup((u64 *)(data + 2));
 529                                 *(u64 *)(data + 2) = tmp;
 530                                 break;
 531                         }
 532                 }
 533                 if (!(current_thread_info()->fpsaved[0] & FPRS_FEF)) {
 534                         current_thread_info()->fpsaved[0] = FPRS_FEF;
 535                         current_thread_info()->gsr[0] = 0;
 536                 }
 537                 if (!(current_thread_info()->fpsaved[0] & flag)) {
 538                         if (freg < 32)
 539                                 memset(f->regs, 0, 32*sizeof(u32));
 540                         else
 541                                 memset(f->regs+32, 0, 32*sizeof(u32));
 542                 }
 543                 memcpy(f->regs + freg, data, size * 4);
 544                 current_thread_info()->fpsaved[0] |= flag;
 545         }
 546         advance(regs);
 547         return 1;
 548 }
 549
 550 void handle_ld_nf(u32 insn, struct pt_regs *regs)
 551 {
 552         int rd = ((insn >> 25) & 0x1f);
 553         int from_kernel = (regs->tstate & TSTATE_PRIV) != 0;
 554         unsigned long *reg;
 555
 556         perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS, 1, regs, 0);
 557
 558         maybe_flush_windows(0, 0, rd, from_kernel);
 559         reg = fetch_reg_addr(rd, regs);
 560         if (from_kernel || rd < 16) {
 561                 reg[0] = 0;
 562                 if ((insn & 0x780000) == 0x180000)
 563                         reg[1] = 0;
 564         } else if (test_thread_flag(TIF_32BIT)) {
 565                 put_user(0, (int __user *) reg);
 566                 if ((insn & 0x780000) == 0x180000)
 567                         put_user(0, ((int __user *) reg) + 1);
 568         } else {
 569                 put_user(0, (unsigned long __user *) reg);
 570                 if ((insn & 0x780000) == 0x180000)
 571                         put_user(0, (unsigned long __user *) reg + 1);
 572         }
 573         advance(regs);
 574 }
 575
 576 void handle_lddfmna(struct pt_regs *regs, unsigned long sfar, unsigned long sfsr)
 577 {
 578         unsigned long pc = regs->tpc;
 579         unsigned long tstate = regs->tstate;
 580         u32 insn;
 581         u64 value;
 582         u8 freg;
 583         int flag;
 584         struct fpustate *f = FPUSTATE;
 585
 586         if (tstate & TSTATE_PRIV)
 587                 die_if_kernel("lddfmna from kernel", regs);
 588         perf_sw_event(PERF_COUNT_SW_ALIGNMENT_FAULTS, 1, regs, sfar);
 589         if (test_thread_flag(TIF_32BIT))
 590                 pc = (u32)pc;
 591         if (get_user(insn, (u32 __user *) pc) != -EFAULT) {
 592                 int asi = decode_asi(insn, regs);
 593                 u32 first, second;
 594                 int err;
 595
 596                 if ((asi > ASI_SNFL) ||
 597                     (asi < ASI_P))
 598                         goto daex;
 599                 first = second = 0;
 600                 err = get_user(first, (u32 __user *)sfar);
 601                 if (!err)
 602                         err = get_user(second, (u32 __user *)(sfar + 4));
 603                 if (err) {
 604                         if (!(asi & 0x2))
 605                                 goto daex;
 606                         first = second = 0;
 607                 }
 608                 save_and_clear_fpu();
 609                 freg = ((insn >> 25) & 0x1e) | ((insn >> 20) & 0x20);
 610                 value = (((u64)first) << 32) | second;
 611                 if (asi & 0x8) /* Little */
 612                         value = __swab64p(&value);
 613                 flag = (freg < 32) ? FPRS_DL : FPRS_DU;
 614                 if (!(current_thread_info()->fpsaved[0] & FPRS_FEF)) {
 615                         current_thread_info()->fpsaved[0] = FPRS_FEF;
 616                         current_thread_info()->gsr[0] = 0;
 617                 }
 618                 if (!(current_thread_info()->fpsaved[0] & flag)) {
 619                         if (freg < 32)
 620                                 memset(f->regs, 0, 32*sizeof(u32));
 621                         else
 622                                 memset(f->regs+32, 0, 32*sizeof(u32));
 623                 }
 624                 *(u64 *)(f->regs + freg) = value;
 625                 current_thread_info()->fpsaved[0] |= flag;
 626         } else {
 627 daex:
 628                 if (tlb_type == hypervisor)
 629                         sun4v_data_access_exception(regs, sfar, sfsr);
 630                 else
 631                         spitfire_data_access_exception(regs, sfsr, sfar);
 632                 return;
 633         }
 634         advance(regs);
 635 }
 636
 637 void handle_stdfmna(struct pt_regs *regs, unsigned long sfar, unsigned long sfsr)
 638 {
 639         unsigned long pc = regs->tpc;
 640         unsigned long tstate = regs->tstate;
 641         u32 insn;
 642         u64 value;
 643         u8 freg;
 644         int flag;
 645         struct fpustate *f = FPUSTATE;
 646
 647         if (tstate & TSTATE_PRIV)
 648                 die_if_kernel("stdfmna from kernel", regs);
 649         perf_sw_event(PERF_COUNT_SW_ALIGNMENT_FAULTS, 1, regs, sfar);
 650         if (test_thread_flag(TIF_32BIT))
 651                 pc = (u32)pc;
 652         if (get_user(insn, (u32 __user *) pc) != -EFAULT) {
 653                 int asi = decode_asi(insn, regs);
 654                 freg = ((insn >> 25) & 0x1e) | ((insn >> 20) & 0x20);
 655                 value = 0;
 656                 flag = (freg < 32) ? FPRS_DL : FPRS_DU;
 657                 if ((asi > ASI_SNFL) ||
 658                     (asi < ASI_P))
 659                         goto daex;
 660                 save_and_clear_fpu();
 661                 if (current_thread_info()->fpsaved[0] & flag)
 662                         value = *(u64 *)&f->regs[freg];
 663                 switch (asi) {
 664                 case ASI_P:
 665                 case ASI_S: break;
 666                 case ASI_PL:
 667                 case ASI_SL:
 668                         value = __swab64p(&value); break;
 669                 default: goto daex;
 670                 }
 671                 if (put_user (value >> 32, (u32 __user *) sfar) ||
 672                     __put_user ((u32)value, (u32 __user *)(sfar + 4)))
 673                         goto daex;
 674         } else {
 675 daex:
 676                 if (tlb_type == hypervisor)
 677                         sun4v_data_access_exception(regs, sfar, sfsr);
 678                 else
 679                         spitfire_data_access_exception(regs, sfsr, sfar);
 680                 return;
 681         }
 682         advance(regs);
 683 }