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/uaccess.h>
  20 #include <linux/smp.h>
  21 #include <linux/bitops.h>
  22 #include <linux/perf_event.h>
  23 #include <linux/ratelimit.h>
  24 #include <linux/context_tracking.h>
  25 #include <asm/fpumacro.h>
  26 #include <asm/cacheflush.h>
  27
  28 #include "entry.h"
  29
  30 enum direction {
  31         load,    /* ld, ldd, ldh, ldsh */
  32         store,   /* st, std, sth, stsh */
  33         both,    /* Swap, ldstub, cas, ... */
  34         fpld,
  35         fpst,
  36         invalid,
  37 };
  38
  39 static inline enum direction decode_direction(unsigned int insn)
  40 {
  41         unsigned long tmp = (insn >> 21) & 1;
  42
  43         if (!tmp)
  44                 return load;
  45         else {
  46                 switch ((insn>>19)&0xf) {
  47                 case 15: /* swap* */
  48                         return both;
  49                 default:
  50                         return store;
  51                 }
  52         }
  53 }
  54
  55 /* 16 = double-word, 8 = extra-word, 4 = word, 2 = half-word */
  56 static inline int decode_access_size(struct pt_regs *regs, unsigned int insn)
  57 {
  58         unsigned int tmp;
  59
  60         tmp = ((insn >> 19) & 0xf);
  61         if (tmp == 11 || tmp == 14) /* ldx/stx */
  62                 return 8;
  63         tmp &= 3;
  64         if (!tmp)
  65                 return 4;
  66         else if (tmp == 3)
  67                 return 16;      /* ldd/std - Although it is actually 8 */
  68         else if (tmp == 2)
  69                 return 2;
  70         else {
  71                 printk("Impossible unaligned trap. insn=%08x\n", insn);
  72                 die_if_kernel("Byte sized unaligned access?!?!", regs);
  73
  74                 /* GCC should never warn that control reaches the end
  75                  * of this function without returning a value because
  76                  * die_if_kernel() is marked with attribute 'noreturn'.
  77                  * Alas, some versions do...
  78                  */
  79
  80                 return 0;
  81         }
  82 }
  83
  84 static inline int decode_asi(unsigned int insn, struct pt_regs *regs)
  85 {
  86         if (insn & 0x800000) {
  87                 if (insn & 0x2000)
  88                         return (unsigned char)(regs->tstate >> 24);     /* %asi */
  89                 else
  90                         return (unsigned char)(insn >> 5);              /* imm_asi */
  91         } else
  92                 return ASI_P;
  93 }
  94
  95 /* 0x400000 = signed, 0 = unsigned */
  96 static inline int decode_signedness(unsigned int insn)
  97 {
  98         return (insn & 0x400000);
  99 }
 100
 101 static inline void maybe_flush_windows(unsigned int rs1, unsigned int rs2,
 102                                        unsigned int rd, int from_kernel)
 103 {
 104         if (rs2 >= 16 || rs1 >= 16 || rd >= 16) {
 105                 if (from_kernel != 0)
 106                         __asm__ __volatile__("flushw");
 107                 else
 108                         flushw_user();
 109         }
 110 }
 111
 112 static inline long sign_extend_imm13(long imm)
 113 {
 114         return imm << 51 >> 51;
 115 }
 116
 117 static unsigned long fetch_reg(unsigned int reg, struct pt_regs *regs)
 118 {
 119         unsigned long value, fp;
 120
 121         if (reg < 16)
 122                 return (!reg ? 0 : regs->u_regs[reg]);
 123
 124         fp = regs->u_regs[UREG_FP];
 125
 126         if (regs->tstate & TSTATE_PRIV) {
 127                 struct reg_window *win;
 128                 win = (struct reg_window *)(fp + STACK_BIAS);
 129                 value = win->locals[reg - 16];
 130         } else if (!test_thread_64bit_stack(fp)) {
 131                 struct reg_window32 __user *win32;
 132                 win32 = (struct reg_window32 __user *)((unsigned long)((u32)fp));
 133                 get_user(value, &win32->locals[reg - 16]);
 134         } else {
 135                 struct reg_window __user *win;
 136                 win = (struct reg_window __user *)(fp + STACK_BIAS);
 137                 get_user(value, &win->locals[reg - 16]);
 138         }
 139         return value;
 140 }
 141
 142 static unsigned long *fetch_reg_addr(unsigned int reg, struct pt_regs *regs)
 143 {
 144         unsigned long fp;
 145
 146         if (reg < 16)
 147                 return &regs->u_regs[reg];
 148
 149         fp = regs->u_regs[UREG_FP];
 150
 151         if (regs->tstate & TSTATE_PRIV) {
 152                 struct reg_window *win;
 153                 win = (struct reg_window *)(fp + STACK_BIAS);
 154                 return &win->locals[reg - 16];
 155         } else if (!test_thread_64bit_stack(fp)) {
 156                 struct reg_window32 *win32;
 157                 win32 = (struct reg_window32 *)((unsigned long)((u32)fp));
 158                 return (unsigned long *)&win32->locals[reg - 16];
 159         } else {
 160                 struct reg_window *win;
 161                 win = (struct reg_window *)(fp + STACK_BIAS);
 162                 return &win->locals[reg - 16];
 163         }
 164 }
 165
 166 unsigned long compute_effective_address(struct pt_regs *regs,
 167                                         unsigned int insn, unsigned int rd)
 168 {
 169         int from_kernel = (regs->tstate & TSTATE_PRIV) != 0;
 170         unsigned int rs1 = (insn >> 14) & 0x1f;
 171         unsigned int rs2 = insn & 0x1f;
 172         unsigned long addr;
 173
 174         if (insn & 0x2000) {
 175                 maybe_flush_windows(rs1, 0, rd, from_kernel);
 176                 addr = (fetch_reg(rs1, regs) + sign_extend_imm13(insn));
 177         } else {
 178                 maybe_flush_windows(rs1, rs2, rd, from_kernel);
 179                 addr = (fetch_reg(rs1, regs) + fetch_reg(rs2, regs));
 180         }
 181
 182         if (!from_kernel && test_thread_flag(TIF_32BIT))
 183                 addr &= 0xffffffff;
 184
 185         return addr;
 186 }
 187
 188 /* This is just to make gcc think die_if_kernel does return... */
 189 static void __used unaligned_panic(char *str, struct pt_regs *regs)
 190 {
 191         die_if_kernel(str, regs);
 192 }
 193
 194 extern int do_int_load(unsigned long *dest_reg, int size,
 195                        unsigned long *saddr, int is_signed, int asi);
 196
 197 extern int __do_int_store(unsigned long *dst_addr, int size,
 198                           unsigned long src_val, int asi);
 199
 200 static inline int do_int_store(int reg_num, int size, unsigned long *dst_addr,
 201                                struct pt_regs *regs, int asi, int orig_asi)
 202 {
 203         unsigned long zero = 0;
 204         unsigned long *src_val_p = &zero;
 205         unsigned long src_val;
 206
 207         if (size == 16) {
 208                 size = 8;
 209                 zero = (((long)(reg_num ?
 210                         (unsigned)fetch_reg(reg_num, regs) : 0)) << 32) |
 211                         (unsigned)fetch_reg(reg_num + 1, regs);
 212         } else if (reg_num) {
 213                 src_val_p = fetch_reg_addr(reg_num, regs);
 214         }
 215         src_val = *src_val_p;
 216         if (unlikely(asi != orig_asi)) {
 217                 switch (size) {
 218                 case 2:
 219                         src_val = swab16(src_val);
 220                         break;
 221                 case 4:
 222                         src_val = swab32(src_val);
 223                         break;
 224                 case 8:
 225                         src_val = swab64(src_val);
 226                         break;
 227                 case 16:
 228                 default:
 229                         BUG();
 230                         break;
 231                 }
 232         }
 233         return __do_int_store(dst_addr, size, src_val, asi);
 234 }
 235
 236 static inline void advance(struct pt_regs *regs)
 237 {
 238         regs->tpc   = regs->tnpc;
 239         regs->tnpc += 4;
 240         if (test_thread_flag(TIF_32BIT)) {
 241                 regs->tpc &= 0xffffffff;
 242                 regs->tnpc &= 0xffffffff;
 243         }
 244 }
 245
 246 static inline int floating_point_load_or_store_p(unsigned int insn)
 247 {
 248         return (insn >> 24) & 1;
 249 }
 250
 251 static inline int ok_for_kernel(unsigned int insn)
 252 {
 253         return !floating_point_load_or_store_p(insn);
 254 }
 255
 256 static void kernel_mna_trap_fault(int fixup_tstate_asi)
 257 {
 258         struct pt_regs *regs = current_thread_info()->kern_una_regs;
 259         unsigned int insn = current_thread_info()->kern_una_insn;
 260         const struct exception_table_entry *entry;
 261
 262         entry = search_exception_tables(regs->tpc);
 263         if (!entry) {
 264                 unsigned long address;
 265
 266                 address = compute_effective_address(regs, insn,
 267                                                     ((insn >> 25) & 0x1f));
 268                 if (address < PAGE_SIZE) {
 269                         printk(KERN_ALERT "Unable to handle kernel NULL "
 270                                "pointer dereference in mna handler");
 271                 } else
 272                         printk(KERN_ALERT "Unable to handle kernel paging "
 273                                "request in mna handler");
 274                 printk(KERN_ALERT " at virtual address %016lx\n",address);
 275                 printk(KERN_ALERT "current->{active_,}mm->context = %016lx\n",
 276                         (current->mm ? CTX_HWBITS(current->mm->context) :
 277                         CTX_HWBITS(current->active_mm->context)));
 278                 printk(KERN_ALERT "current->{active_,}mm->pgd = %016lx\n",
 279                         (current->mm ? (unsigned long) current->mm->pgd :
 280                         (unsigned long) current->active_mm->pgd));
 281                 die_if_kernel("Oops", regs);
 282                 /* Not reached */
 283         }
 284         regs->tpc = entry->fixup;
 285         regs->tnpc = regs->tpc + 4;
 286
 287         if (fixup_tstate_asi) {
 288                 regs->tstate &= ~TSTATE_ASI;
 289                 regs->tstate |= (ASI_AIUS << 24UL);
 290         }
 291 }
 292
 293 static void log_unaligned(struct pt_regs *regs)
 294 {
 295         static DEFINE_RATELIMIT_STATE(ratelimit, 5 * HZ, 5);
 296
 297         if (__ratelimit(&ratelimit)) {
 298                 printk("Kernel unaligned access at TPC[%lx] %pS\n",
 299                        regs->tpc, (void *) regs->tpc);
 300         }
 301 }
 302
 303 asmlinkage void kernel_unaligned_trap(struct pt_regs *regs, unsigned int insn)
 304 {
 305         enum direction dir = decode_direction(insn);
 306         int size = decode_access_size(regs, insn);
 307         int orig_asi, asi;
 308
 309         current_thread_info()->kern_una_regs = regs;
 310         current_thread_info()->kern_una_insn = insn;
 311
 312         orig_asi = asi = decode_asi(insn, regs);
 313
 314         /* If this is a {get,put}_user() on an unaligned userspace pointer,
 315          * just signal a fault and do not log the event.
 316          */
 317         if (asi == ASI_AIUS) {
 318                 kernel_mna_trap_fault(0);
 319                 return;
 320         }
 321
 322         log_unaligned(regs);
 323
 324         if (!ok_for_kernel(insn) || dir == both) {
 325                 printk("Unsupported unaligned load/store trap for kernel "
 326                        "at <%016lx>.\n", regs->tpc);
 327                 unaligned_panic("Kernel does fpu/atomic "
 328                                 "unaligned load/store.", regs);
 329
 330                 kernel_mna_trap_fault(0);
 331         } else {
 332                 unsigned long addr, *reg_addr;
 333                 int err;
 334
 335                 addr = compute_effective_address(regs, insn,
 336                                                  ((insn >> 25) & 0x1f));
 337                 perf_sw_event(PERF_COUNT_SW_ALIGNMENT_FAULTS, 1, regs, addr);
 338                 switch (asi) {
 339                 case ASI_NL:
 340                 case ASI_AIUPL:
 341                 case ASI_AIUSL:
 342                 case ASI_PL:
 343                 case ASI_SL:
 344                 case ASI_PNFL:
 345                 case ASI_SNFL:
 346                         asi &= ~0x08;
 347                         break;
 348                 }
 349                 switch (dir) {
 350                 case load:
 351                         reg_addr = fetch_reg_addr(((insn>>25)&0x1f), regs);
 352                         err = do_int_load(reg_addr, size,
 353                                           (unsigned long *) addr,
 354                                           decode_signedness(insn), asi);
 355                         if (likely(!err) && unlikely(asi != orig_asi)) {
 356                                 unsigned long val_in = *reg_addr;
 357                                 switch (size) {
 358                                 case 2:
 359                                         val_in = swab16(val_in);
 360                                         break;
 361                                 case 4:
 362                                         val_in = swab32(val_in);
 363                                         break;
 364                                 case 8:
 365                                         val_in = swab64(val_in);
 366                                         break;
 367                                 case 16:
 368                                 default:
 369                                         BUG();
 370                                         break;
 371                                 }
 372                                 *reg_addr = val_in;
 373                         }
 374                         break;
 375
 376                 case store:
 377                         err = do_int_store(((insn>>25)&0x1f), size,
 378                                            (unsigned long *) addr, regs,
 379                                            asi, orig_asi);
 380                         break;
 381
 382                 default:
 383                         panic("Impossible kernel unaligned trap.");
 384                         /* Not reached... */
 385                 }
 386                 if (unlikely(err))
 387                         kernel_mna_trap_fault(1);
 388                 else
 389                         advance(regs);
 390         }
 391 }
 392
 393 int handle_popc(u32 insn, struct pt_regs *regs)
 394 {
 395         int from_kernel = (regs->tstate & TSTATE_PRIV) != 0;
 396         int ret, rd = ((insn >> 25) & 0x1f);
 397         u64 value;
 398
 399         perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS, 1, regs, 0);
 400         if (insn & 0x2000) {
 401                 maybe_flush_windows(0, 0, rd, from_kernel);
 402                 value = sign_extend_imm13(insn);
 403         } else {
 404                 maybe_flush_windows(0, insn & 0x1f, rd, from_kernel);
 405                 value = fetch_reg(insn & 0x1f, regs);
 406         }
 407         ret = hweight64(value);
 408         if (rd < 16) {
 409                 if (rd)
 410                         regs->u_regs[rd] = ret;
 411         } else {
 412                 unsigned long fp = regs->u_regs[UREG_FP];
 413
 414                 if (!test_thread_64bit_stack(fp)) {
 415                         struct reg_window32 __user *win32;
 416                         win32 = (struct reg_window32 __user *)((unsigned long)((u32)fp));
 417                         put_user(ret, &win32->locals[rd - 16]);
 418                 } else {
 419                         struct reg_window __user *win;
 420                         win = (struct reg_window __user *)(fp + STACK_BIAS);
 421                         put_user(ret, &win->locals[rd - 16]);
 422                 }
 423         }
 424         advance(regs);
 425         return 1;
 426 }
 427
 428 extern void do_fpother(struct pt_regs *regs);
 429 extern void do_privact(struct pt_regs *regs);
 430 extern void sun4v_data_access_exception(struct pt_regs *regs,
 431                                         unsigned long addr,
 432                                         unsigned long type_ctx);
 433
 434 int handle_ldf_stq(u32 insn, struct pt_regs *regs)
 435 {
 436         unsigned long addr = compute_effective_address(regs, insn, 0);
 437         int freg = ((insn >> 25) & 0x1e) | ((insn >> 20) & 0x20);
 438         struct fpustate *f = FPUSTATE;
 439         int asi = decode_asi(insn, regs);
 440         int flag = (freg < 32) ? FPRS_DL : FPRS_DU;
 441
 442         perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS, 1, regs, 0);
 443
 444         save_and_clear_fpu();
 445         current_thread_info()->xfsr[0] &= ~0x1c000;
 446         if (freg & 3) {
 447                 current_thread_info()->xfsr[0] |= (6 << 14) /* invalid_fp_register */;
 448                 do_fpother(regs);
 449                 return 0;
 450         }
 451         if (insn & 0x200000) {
 452                 /* STQ */
 453                 u64 first = 0, second = 0;
 454
 455                 if (current_thread_info()->fpsaved[0] & flag) {
 456                         first = *(u64 *)&f->regs[freg];
 457                         second = *(u64 *)&f->regs[freg+2];
 458                 }
 459                 if (asi < 0x80) {
 460                         do_privact(regs);
 461                         return 1;
 462                 }
 463                 switch (asi) {
 464                 case ASI_P:
 465                 case ASI_S: break;
 466                 case ASI_PL:
 467                 case ASI_SL:
 468                         {
 469                                 /* Need to convert endians */
 470                                 u64 tmp = __swab64p(&first);
 471
 472                                 first = __swab64p(&second);
 473                                 second = tmp;
 474                                 break;
 475                         }
 476                 default:
 477                         if (tlb_type == hypervisor)
 478                                 sun4v_data_access_exception(regs, addr, 0);
 479                         else
 480                                 spitfire_data_access_exception(regs, 0, addr);
 481                         return 1;
 482                 }
 483                 if (put_user (first >> 32, (u32 __user *)addr) ||
 484                     __put_user ((u32)first, (u32 __user *)(addr + 4)) ||
 485                     __put_user (second >> 32, (u32 __user *)(addr + 8)) ||
 486                     __put_user ((u32)second, (u32 __user *)(addr + 12))) {
 487                         if (tlb_type == hypervisor)
 488                                 sun4v_data_access_exception(regs, addr, 0);
 489                         else
 490                                 spitfire_data_access_exception(regs, 0, addr);
 491                         return 1;
 492                 }
 493         } else {
 494                 /* LDF, LDDF, LDQF */
 495                 u32 data[4] __attribute__ ((aligned(8)));
 496                 int size, i;
 497                 int err;
 498
 499                 if (asi < 0x80) {
 500                         do_privact(regs);
 501                         return 1;
 502                 } else if (asi > ASI_SNFL) {
 503                         if (tlb_type == hypervisor)
 504                                 sun4v_data_access_exception(regs, addr, 0);
 505                         else
 506                                 spitfire_data_access_exception(regs, 0, addr);
 507                         return 1;
 508                 }
 509                 switch (insn & 0x180000) {
 510                 case 0x000000: size = 1; break;
 511                 case 0x100000: size = 4; break;
 512                 default: size = 2; break;
 513                 }
 514                 for (i = 0; i < size; i++)
 515                         data[i] = 0;
 516
 517                 err = get_user (data[0], (u32 __user *) addr);
 518                 if (!err) {
 519                         for (i = 1; i < size; i++)
 520                                 err |= __get_user (data[i], (u32 __user *)(addr + 4*i));
 521                 }
 522                 if (err && !(asi & 0x2 /* NF */)) {
 523                         if (tlb_type == hypervisor)
 524                                 sun4v_data_access_exception(regs, addr, 0);
 525                         else
 526                                 spitfire_data_access_exception(regs, 0, addr);
 527                         return 1;
 528                 }
 529                 if (asi & 0x8) /* Little */ {
 530                         u64 tmp;
 531
 532                         switch (size) {
 533                         case 1: data[0] = le32_to_cpup(data + 0); break;
 534                         default:*(u64 *)(data + 0) = le64_to_cpup((u64 *)(data + 0));
 535                                 break;
 536                         case 4: tmp = le64_to_cpup((u64 *)(data + 0));
 537                                 *(u64 *)(data + 0) = le64_to_cpup((u64 *)(data + 2));
 538                                 *(u64 *)(data + 2) = tmp;
 539                                 break;
 540                         }
 541                 }
 542                 if (!(current_thread_info()->fpsaved[0] & FPRS_FEF)) {
 543                         current_thread_info()->fpsaved[0] = FPRS_FEF;
 544                         current_thread_info()->gsr[0] = 0;
 545                 }
 546                 if (!(current_thread_info()->fpsaved[0] & flag)) {
 547                         if (freg < 32)
 548                                 memset(f->regs, 0, 32*sizeof(u32));
 549                         else
 550                                 memset(f->regs+32, 0, 32*sizeof(u32));
 551                 }
 552                 memcpy(f->regs + freg, data, size * 4);
 553                 current_thread_info()->fpsaved[0] |= flag;
 554         }
 555         advance(regs);
 556         return 1;
 557 }
 558
 559 void handle_ld_nf(u32 insn, struct pt_regs *regs)
 560 {
 561         int rd = ((insn >> 25) & 0x1f);
 562         int from_kernel = (regs->tstate & TSTATE_PRIV) != 0;
 563         unsigned long *reg;
 564
 565         perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS, 1, regs, 0);
 566
 567         maybe_flush_windows(0, 0, rd, from_kernel);
 568         reg = fetch_reg_addr(rd, regs);
 569         if (from_kernel || rd < 16) {
 570                 reg[0] = 0;
 571                 if ((insn & 0x780000) == 0x180000)
 572                         reg[1] = 0;
 573         } else if (!test_thread_64bit_stack(regs->u_regs[UREG_FP])) {
 574                 put_user(0, (int __user *) reg);
 575                 if ((insn & 0x780000) == 0x180000)
 576                         put_user(0, ((int __user *) reg) + 1);
 577         } else {
 578                 put_user(0, (unsigned long __user *) reg);
 579                 if ((insn & 0x780000) == 0x180000)
 580                         put_user(0, (unsigned long __user *) reg + 1);
 581         }
 582         advance(regs);
 583 }
 584
 585 void handle_lddfmna(struct pt_regs *regs, unsigned long sfar, unsigned long sfsr)
 586 {
 587         enum ctx_state prev_state = exception_enter();
 588         unsigned long pc = regs->tpc;
 589         unsigned long tstate = regs->tstate;
 590         u32 insn;
 591         u64 value;
 592         u8 freg;
 593         int flag;
 594         struct fpustate *f = FPUSTATE;
 595
 596         if (tstate & TSTATE_PRIV)
 597                 die_if_kernel("lddfmna from kernel", regs);
 598         perf_sw_event(PERF_COUNT_SW_ALIGNMENT_FAULTS, 1, regs, sfar);
 599         if (test_thread_flag(TIF_32BIT))
 600                 pc = (u32)pc;
 601         if (get_user(insn, (u32 __user *) pc) != -EFAULT) {
 602                 int asi = decode_asi(insn, regs);
 603                 u32 first, second;
 604                 int err;
 605
 606                 if ((asi > ASI_SNFL) ||
 607                     (asi < ASI_P))
 608                         goto daex;
 609                 first = second = 0;
 610                 err = get_user(first, (u32 __user *)sfar);
 611                 if (!err)
 612                         err = get_user(second, (u32 __user *)(sfar + 4));
 613                 if (err) {
 614                         if (!(asi & 0x2))
 615                                 goto daex;
 616                         first = second = 0;
 617                 }
 618                 save_and_clear_fpu();
 619                 freg = ((insn >> 25) & 0x1e) | ((insn >> 20) & 0x20);
 620                 value = (((u64)first) << 32) | second;
 621                 if (asi & 0x8) /* Little */
 622                         value = __swab64p(&value);
 623                 flag = (freg < 32) ? FPRS_DL : FPRS_DU;
 624                 if (!(current_thread_info()->fpsaved[0] & FPRS_FEF)) {
 625                         current_thread_info()->fpsaved[0] = FPRS_FEF;
 626                         current_thread_info()->gsr[0] = 0;
 627                 }
 628                 if (!(current_thread_info()->fpsaved[0] & flag)) {
 629                         if (freg < 32)
 630                                 memset(f->regs, 0, 32*sizeof(u32));
 631                         else
 632                                 memset(f->regs+32, 0, 32*sizeof(u32));
 633                 }
 634                 *(u64 *)(f->regs + freg) = value;
 635                 current_thread_info()->fpsaved[0] |= flag;
 636         } else {
 637 daex:
 638                 if (tlb_type == hypervisor)
 639                         sun4v_data_access_exception(regs, sfar, sfsr);
 640                 else
 641                         spitfire_data_access_exception(regs, sfsr, sfar);
 642                 goto out;
 643         }
 644         advance(regs);
 645 out:
 646         exception_exit(prev_state);
 647 }
 648
 649 void handle_stdfmna(struct pt_regs *regs, unsigned long sfar, unsigned long sfsr)
 650 {
 651         enum ctx_state prev_state = exception_enter();
 652         unsigned long pc = regs->tpc;
 653         unsigned long tstate = regs->tstate;
 654         u32 insn;
 655         u64 value;
 656         u8 freg;
 657         int flag;
 658         struct fpustate *f = FPUSTATE;
 659
 660         if (tstate & TSTATE_PRIV)
 661                 die_if_kernel("stdfmna from kernel", regs);
 662         perf_sw_event(PERF_COUNT_SW_ALIGNMENT_FAULTS, 1, regs, sfar);
 663         if (test_thread_flag(TIF_32BIT))
 664                 pc = (u32)pc;
 665         if (get_user(insn, (u32 __user *) pc) != -EFAULT) {
 666                 int asi = decode_asi(insn, regs);
 667                 freg = ((insn >> 25) & 0x1e) | ((insn >> 20) & 0x20);
 668                 value = 0;
 669                 flag = (freg < 32) ? FPRS_DL : FPRS_DU;
 670                 if ((asi > ASI_SNFL) ||
 671                     (asi < ASI_P))
 672                         goto daex;
 673                 save_and_clear_fpu();
 674                 if (current_thread_info()->fpsaved[0] & flag)
 675                         value = *(u64 *)&f->regs[freg];
 676                 switch (asi) {
 677                 case ASI_P:
 678                 case ASI_S: break;
 679                 case ASI_PL:
 680                 case ASI_SL:
 681                         value = __swab64p(&value); break;
 682                 default: goto daex;
 683                 }
 684                 if (put_user (value >> 32, (u32 __user *) sfar) ||
 685                     __put_user ((u32)value, (u32 __user *)(sfar + 4)))
 686                         goto daex;
 687         } else {
 688 daex:
 689                 if (tlb_type == hypervisor)
 690                         sun4v_data_access_exception(regs, sfar, sfsr);
 691                 else
 692                         spitfire_data_access_exception(regs, sfsr, sfar);
 693                 goto out;
 694         }
 695         advance(regs);
 696 out:
 697         exception_exit(prev_state);
 698 }