Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/shaggy...
[linux-2.6] / arch / sparc64 / kernel / unaligned.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 David S. Miller (davem@caip.rutgers.edu)
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/kallsyms.h>
24 #include <asm/fpumacro.h>
25
26 /* #define DEBUG_MNA */
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 #ifdef DEBUG_MNA
38 static char *dirstrings[] = {
39   "load", "store", "both", "fpload", "fpstore", "invalid"
40 };
41 #endif
42
43 static inline enum direction decode_direction(unsigned int insn)
44 {
45         unsigned long tmp = (insn >> 21) & 1;
46
47         if (!tmp)
48                 return load;
49         else {
50                 switch ((insn>>19)&0xf) {
51                 case 15: /* swap* */
52                         return both;
53                 default:
54                         return store;
55                 }
56         }
57 }
58
59 /* 16 = double-word, 8 = extra-word, 4 = word, 2 = half-word */
60 static inline int decode_access_size(unsigned int insn)
61 {
62         unsigned int tmp;
63
64         tmp = ((insn >> 19) & 0xf);
65         if (tmp == 11 || tmp == 14) /* ldx/stx */
66                 return 8;
67         tmp &= 3;
68         if (!tmp)
69                 return 4;
70         else if (tmp == 3)
71                 return 16;      /* ldd/std - Although it is actually 8 */
72         else if (tmp == 2)
73                 return 2;
74         else {
75                 printk("Impossible unaligned trap. insn=%08x\n", insn);
76                 die_if_kernel("Byte sized unaligned access?!?!", current_thread_info()->kregs);
77
78                 /* GCC should never warn that control reaches the end
79                  * of this function without returning a value because
80                  * die_if_kernel() is marked with attribute 'noreturn'.
81                  * Alas, some versions do...
82                  */
83
84                 return 0;
85         }
86 }
87
88 static inline int decode_asi(unsigned int insn, struct pt_regs *regs)
89 {
90         if (insn & 0x800000) {
91                 if (insn & 0x2000)
92                         return (unsigned char)(regs->tstate >> 24);     /* %asi */
93                 else
94                         return (unsigned char)(insn >> 5);              /* imm_asi */
95         } else
96                 return ASI_P;
97 }
98
99 /* 0x400000 = signed, 0 = unsigned */
100 static inline int decode_signedness(unsigned int insn)
101 {
102         return (insn & 0x400000);
103 }
104
105 static inline void maybe_flush_windows(unsigned int rs1, unsigned int rs2,
106                                        unsigned int rd, int from_kernel)
107 {
108         if (rs2 >= 16 || rs1 >= 16 || rd >= 16) {
109                 if (from_kernel != 0)
110                         __asm__ __volatile__("flushw");
111                 else
112                         flushw_user();
113         }
114 }
115
116 static inline long sign_extend_imm13(long imm)
117 {
118         return imm << 51 >> 51;
119 }
120
121 static unsigned long fetch_reg(unsigned int reg, struct pt_regs *regs)
122 {
123         unsigned long value;
124         
125         if (reg < 16)
126                 return (!reg ? 0 : regs->u_regs[reg]);
127         if (regs->tstate & TSTATE_PRIV) {
128                 struct reg_window *win;
129                 win = (struct reg_window *)(regs->u_regs[UREG_FP] + STACK_BIAS);
130                 value = win->locals[reg - 16];
131         } else if (test_thread_flag(TIF_32BIT)) {
132                 struct reg_window32 __user *win32;
133                 win32 = (struct reg_window32 __user *)((unsigned long)((u32)regs->u_regs[UREG_FP]));
134                 get_user(value, &win32->locals[reg - 16]);
135         } else {
136                 struct reg_window __user *win;
137                 win = (struct reg_window __user *)(regs->u_regs[UREG_FP] + STACK_BIAS);
138                 get_user(value, &win->locals[reg - 16]);
139         }
140         return value;
141 }
142
143 static unsigned long *fetch_reg_addr(unsigned int reg, struct pt_regs *regs)
144 {
145         if (reg < 16)
146                 return &regs->u_regs[reg];
147         if (regs->tstate & TSTATE_PRIV) {
148                 struct reg_window *win;
149                 win = (struct reg_window *)(regs->u_regs[UREG_FP] + STACK_BIAS);
150                 return &win->locals[reg - 16];
151         } else if (test_thread_flag(TIF_32BIT)) {
152                 struct reg_window32 *win32;
153                 win32 = (struct reg_window32 *)((unsigned long)((u32)regs->u_regs[UREG_FP]));
154                 return (unsigned long *)&win32->locals[reg - 16];
155         } else {
156                 struct reg_window *win;
157                 win = (struct reg_window *)(regs->u_regs[UREG_FP] + STACK_BIAS);
158                 return &win->locals[reg - 16];
159         }
160 }
161
162 unsigned long compute_effective_address(struct pt_regs *regs,
163                                         unsigned int insn, unsigned int rd)
164 {
165         unsigned int rs1 = (insn >> 14) & 0x1f;
166         unsigned int rs2 = insn & 0x1f;
167         int from_kernel = (regs->tstate & TSTATE_PRIV) != 0;
168
169         if (insn & 0x2000) {
170                 maybe_flush_windows(rs1, 0, rd, from_kernel);
171                 return (fetch_reg(rs1, regs) + sign_extend_imm13(insn));
172         } else {
173                 maybe_flush_windows(rs1, rs2, rd, from_kernel);
174                 return (fetch_reg(rs1, regs) + fetch_reg(rs2, regs));
175         }
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 unsigned long count, last_time;
286
287         if (time_after(jiffies, last_time + 5 * HZ))
288                 count = 0;
289         if (count < 5) {
290                 last_time = jiffies;
291                 count++;
292                 printk("Kernel unaligned access at TPC[%lx] ", regs->tpc);
293                 print_symbol("%s\n", regs->tpc);
294         }
295 }
296
297 asmlinkage void kernel_unaligned_trap(struct pt_regs *regs, unsigned int insn)
298 {
299         enum direction dir = decode_direction(insn);
300         int size = decode_access_size(insn);
301         int orig_asi, asi;
302
303         current_thread_info()->kern_una_regs = regs;
304         current_thread_info()->kern_una_insn = insn;
305
306         orig_asi = asi = decode_asi(insn, regs);
307
308         /* If this is a {get,put}_user() on an unaligned userspace pointer,
309          * just signal a fault and do not log the event.
310          */
311         if (asi == ASI_AIUS) {
312                 kernel_mna_trap_fault(0);
313                 return;
314         }
315
316         log_unaligned(regs);
317
318         if (!ok_for_kernel(insn) || dir == both) {
319                 printk("Unsupported unaligned load/store trap for kernel "
320                        "at <%016lx>.\n", regs->tpc);
321                 unaligned_panic("Kernel does fpu/atomic "
322                                 "unaligned load/store.", regs);
323
324                 kernel_mna_trap_fault(0);
325         } else {
326                 unsigned long addr, *reg_addr;
327                 int err;
328
329                 addr = compute_effective_address(regs, insn,
330                                                  ((insn >> 25) & 0x1f));
331 #ifdef DEBUG_MNA
332                 printk("KMNA: pc=%016lx [dir=%s addr=%016lx size=%d] "
333                        "retpc[%016lx]\n",
334                        regs->tpc, dirstrings[dir], addr, size,
335                        regs->u_regs[UREG_RETPC]);
336 #endif
337                 switch (asi) {
338                 case ASI_NL:
339                 case ASI_AIUPL:
340                 case ASI_AIUSL:
341                 case ASI_PL:
342                 case ASI_SL:
343                 case ASI_PNFL:
344                 case ASI_SNFL:
345                         asi &= ~0x08;
346                         break;
347                 };
348                 switch (dir) {
349                 case load:
350                         reg_addr = fetch_reg_addr(((insn>>25)&0x1f), regs);
351                         err = do_int_load(reg_addr, size,
352                                           (unsigned long *) addr,
353                                           decode_signedness(insn), asi);
354                         if (likely(!err) && unlikely(asi != orig_asi)) {
355                                 unsigned long val_in = *reg_addr;
356                                 switch (size) {
357                                 case 2:
358                                         val_in = swab16(val_in);
359                                         break;
360                                 case 4:
361                                         val_in = swab32(val_in);
362                                         break;
363                                 case 8:
364                                         val_in = swab64(val_in);
365                                         break;
366                                 case 16:
367                                 default:
368                                         BUG();
369                                         break;
370                                 };
371                                 *reg_addr = val_in;
372                         }
373                         break;
374
375                 case store:
376                         err = do_int_store(((insn>>25)&0x1f), size,
377                                            (unsigned long *) addr, regs,
378                                            asi, orig_asi);
379                         break;
380
381                 default:
382                         panic("Impossible kernel unaligned trap.");
383                         /* Not reached... */
384                 }
385                 if (unlikely(err))
386                         kernel_mna_trap_fault(1);
387                 else
388                         advance(regs);
389         }
390 }
391
392 static char popc_helper[] = {
393 0, 1, 1, 2, 1, 2, 2, 3,
394 1, 2, 2, 3, 2, 3, 3, 4, 
395 };
396
397 int handle_popc(u32 insn, struct pt_regs *regs)
398 {
399         u64 value;
400         int ret, i, rd = ((insn >> 25) & 0x1f);
401         int from_kernel = (regs->tstate & TSTATE_PRIV) != 0;
402                                 
403         if (insn & 0x2000) {
404                 maybe_flush_windows(0, 0, rd, from_kernel);
405                 value = sign_extend_imm13(insn);
406         } else {
407                 maybe_flush_windows(0, insn & 0x1f, rd, from_kernel);
408                 value = fetch_reg(insn & 0x1f, regs);
409         }
410         for (ret = 0, i = 0; i < 16; i++) {
411                 ret += popc_helper[value & 0xf];
412                 value >>= 4;
413         }
414         if (rd < 16) {
415                 if (rd)
416                         regs->u_regs[rd] = ret;
417         } else {
418                 if (test_thread_flag(TIF_32BIT)) {
419                         struct reg_window32 __user *win32;
420                         win32 = (struct reg_window32 __user *)((unsigned long)((u32)regs->u_regs[UREG_FP]));
421                         put_user(ret, &win32->locals[rd - 16]);
422                 } else {
423                         struct reg_window __user *win;
424                         win = (struct reg_window __user *)(regs->u_regs[UREG_FP] + STACK_BIAS);
425                         put_user(ret, &win->locals[rd - 16]);
426                 }
427         }
428         advance(regs);
429         return 1;
430 }
431
432 extern void do_fpother(struct pt_regs *regs);
433 extern void do_privact(struct pt_regs *regs);
434 extern void spitfire_data_access_exception(struct pt_regs *regs,
435                                            unsigned long sfsr,
436                                            unsigned long sfar);
437 extern void sun4v_data_access_exception(struct pt_regs *regs,
438                                         unsigned long addr,
439                                         unsigned long type_ctx);
440
441 int handle_ldf_stq(u32 insn, struct pt_regs *regs)
442 {
443         unsigned long addr = compute_effective_address(regs, insn, 0);
444         int freg = ((insn >> 25) & 0x1e) | ((insn >> 20) & 0x20);
445         struct fpustate *f = FPUSTATE;
446         int asi = decode_asi(insn, regs);
447         int flag = (freg < 32) ? FPRS_DL : FPRS_DU;
448
449         save_and_clear_fpu();
450         current_thread_info()->xfsr[0] &= ~0x1c000;
451         if (freg & 3) {
452                 current_thread_info()->xfsr[0] |= (6 << 14) /* invalid_fp_register */;
453                 do_fpother(regs);
454                 return 0;
455         }
456         if (insn & 0x200000) {
457                 /* STQ */
458                 u64 first = 0, second = 0;
459                 
460                 if (current_thread_info()->fpsaved[0] & flag) {
461                         first = *(u64 *)&f->regs[freg];
462                         second = *(u64 *)&f->regs[freg+2];
463                 }
464                 if (asi < 0x80) {
465                         do_privact(regs);
466                         return 1;
467                 }
468                 switch (asi) {
469                 case ASI_P:
470                 case ASI_S: break;
471                 case ASI_PL:
472                 case ASI_SL: 
473                         {
474                                 /* Need to convert endians */
475                                 u64 tmp = __swab64p(&first);
476                                 
477                                 first = __swab64p(&second);
478                                 second = tmp;
479                                 break;
480                         }
481                 default:
482                         if (tlb_type == hypervisor)
483                                 sun4v_data_access_exception(regs, addr, 0);
484                         else
485                                 spitfire_data_access_exception(regs, 0, addr);
486                         return 1;
487                 }
488                 if (put_user (first >> 32, (u32 __user *)addr) ||
489                     __put_user ((u32)first, (u32 __user *)(addr + 4)) ||
490                     __put_user (second >> 32, (u32 __user *)(addr + 8)) ||
491                     __put_user ((u32)second, (u32 __user *)(addr + 12))) {
492                         if (tlb_type == hypervisor)
493                                 sun4v_data_access_exception(regs, addr, 0);
494                         else
495                                 spitfire_data_access_exception(regs, 0, addr);
496                         return 1;
497                 }
498         } else {
499                 /* LDF, LDDF, LDQF */
500                 u32 data[4] __attribute__ ((aligned(8)));
501                 int size, i;
502                 int err;
503
504                 if (asi < 0x80) {
505                         do_privact(regs);
506                         return 1;
507                 } else if (asi > ASI_SNFL) {
508                         if (tlb_type == hypervisor)
509                                 sun4v_data_access_exception(regs, addr, 0);
510                         else
511                                 spitfire_data_access_exception(regs, 0, addr);
512                         return 1;
513                 }
514                 switch (insn & 0x180000) {
515                 case 0x000000: size = 1; break;
516                 case 0x100000: size = 4; break;
517                 default: size = 2; break;
518                 }
519                 for (i = 0; i < size; i++)
520                         data[i] = 0;
521                 
522                 err = get_user (data[0], (u32 __user *) addr);
523                 if (!err) {
524                         for (i = 1; i < size; i++)
525                                 err |= __get_user (data[i], (u32 __user *)(addr + 4*i));
526                 }
527                 if (err && !(asi & 0x2 /* NF */)) {
528                         if (tlb_type == hypervisor)
529                                 sun4v_data_access_exception(regs, addr, 0);
530                         else
531                                 spitfire_data_access_exception(regs, 0, addr);
532                         return 1;
533                 }
534                 if (asi & 0x8) /* Little */ {
535                         u64 tmp;
536
537                         switch (size) {
538                         case 1: data[0] = le32_to_cpup(data + 0); break;
539                         default:*(u64 *)(data + 0) = le64_to_cpup((u64 *)(data + 0));
540                                 break;
541                         case 4: tmp = le64_to_cpup((u64 *)(data + 0));
542                                 *(u64 *)(data + 0) = le64_to_cpup((u64 *)(data + 2));
543                                 *(u64 *)(data + 2) = tmp;
544                                 break;
545                         }
546                 }
547                 if (!(current_thread_info()->fpsaved[0] & FPRS_FEF)) {
548                         current_thread_info()->fpsaved[0] = FPRS_FEF;
549                         current_thread_info()->gsr[0] = 0;
550                 }
551                 if (!(current_thread_info()->fpsaved[0] & flag)) {
552                         if (freg < 32)
553                                 memset(f->regs, 0, 32*sizeof(u32));
554                         else
555                                 memset(f->regs+32, 0, 32*sizeof(u32));
556                 }
557                 memcpy(f->regs + freg, data, size * 4);
558                 current_thread_info()->fpsaved[0] |= flag;
559         }
560         advance(regs);
561         return 1;
562 }
563
564 void handle_ld_nf(u32 insn, struct pt_regs *regs)
565 {
566         int rd = ((insn >> 25) & 0x1f);
567         int from_kernel = (regs->tstate & TSTATE_PRIV) != 0;
568         unsigned long *reg;
569                                 
570         maybe_flush_windows(0, 0, rd, from_kernel);
571         reg = fetch_reg_addr(rd, regs);
572         if (from_kernel || rd < 16) {
573                 reg[0] = 0;
574                 if ((insn & 0x780000) == 0x180000)
575                         reg[1] = 0;
576         } else if (test_thread_flag(TIF_32BIT)) {
577                 put_user(0, (int __user *) reg);
578                 if ((insn & 0x780000) == 0x180000)
579                         put_user(0, ((int __user *) reg) + 1);
580         } else {
581                 put_user(0, (unsigned long __user *) reg);
582                 if ((insn & 0x780000) == 0x180000)
583                         put_user(0, (unsigned long __user *) reg + 1);
584         }
585         advance(regs);
586 }
587
588 void handle_lddfmna(struct pt_regs *regs, unsigned long sfar, unsigned long sfsr)
589 {
590         unsigned long pc = regs->tpc;
591         unsigned long tstate = regs->tstate;
592         u32 insn;
593         u32 first, second;
594         u64 value;
595         u8 freg;
596         int flag;
597         struct fpustate *f = FPUSTATE;
598
599         if (tstate & TSTATE_PRIV)
600                 die_if_kernel("lddfmna from kernel", regs);
601         if (test_thread_flag(TIF_32BIT))
602                 pc = (u32)pc;
603         if (get_user(insn, (u32 __user *) pc) != -EFAULT) {
604                 int asi = decode_asi(insn, regs);
605                 if ((asi > ASI_SNFL) ||
606                     (asi < ASI_P))
607                         goto daex;
608                 if (get_user(first, (u32 __user *)sfar) ||
609                      get_user(second, (u32 __user *)(sfar + 4))) {
610                         if (asi & 0x2) /* NF */ {
611                                 first = 0; second = 0;
612                         } else
613                                 goto daex;
614                 }
615                 save_and_clear_fpu();
616                 freg = ((insn >> 25) & 0x1e) | ((insn >> 20) & 0x20);
617                 value = (((u64)first) << 32) | second;
618                 if (asi & 0x8) /* Little */
619                         value = __swab64p(&value);
620                 flag = (freg < 32) ? FPRS_DL : FPRS_DU;
621                 if (!(current_thread_info()->fpsaved[0] & FPRS_FEF)) {
622                         current_thread_info()->fpsaved[0] = FPRS_FEF;
623                         current_thread_info()->gsr[0] = 0;
624                 }
625                 if (!(current_thread_info()->fpsaved[0] & flag)) {
626                         if (freg < 32)
627                                 memset(f->regs, 0, 32*sizeof(u32));
628                         else
629                                 memset(f->regs+32, 0, 32*sizeof(u32));
630                 }
631                 *(u64 *)(f->regs + freg) = value;
632                 current_thread_info()->fpsaved[0] |= flag;
633         } else {
634 daex:
635                 if (tlb_type == hypervisor)
636                         sun4v_data_access_exception(regs, sfar, sfsr);
637                 else
638                         spitfire_data_access_exception(regs, sfsr, sfar);
639                 return;
640         }
641         advance(regs);
642         return;
643 }
644
645 void handle_stdfmna(struct pt_regs *regs, unsigned long sfar, unsigned long sfsr)
646 {
647         unsigned long pc = regs->tpc;
648         unsigned long tstate = regs->tstate;
649         u32 insn;
650         u64 value;
651         u8 freg;
652         int flag;
653         struct fpustate *f = FPUSTATE;
654
655         if (tstate & TSTATE_PRIV)
656                 die_if_kernel("stdfmna from kernel", regs);
657         if (test_thread_flag(TIF_32BIT))
658                 pc = (u32)pc;
659         if (get_user(insn, (u32 __user *) pc) != -EFAULT) {
660                 int asi = decode_asi(insn, regs);
661                 freg = ((insn >> 25) & 0x1e) | ((insn >> 20) & 0x20);
662                 value = 0;
663                 flag = (freg < 32) ? FPRS_DL : FPRS_DU;
664                 if ((asi > ASI_SNFL) ||
665                     (asi < ASI_P))
666                         goto daex;
667                 save_and_clear_fpu();
668                 if (current_thread_info()->fpsaved[0] & flag)
669                         value = *(u64 *)&f->regs[freg];
670                 switch (asi) {
671                 case ASI_P:
672                 case ASI_S: break;
673                 case ASI_PL:
674                 case ASI_SL: 
675                         value = __swab64p(&value); break;
676                 default: goto daex;
677                 }
678                 if (put_user (value >> 32, (u32 __user *) sfar) ||
679                     __put_user ((u32)value, (u32 __user *)(sfar + 4)))
680                         goto daex;
681         } else {
682 daex:
683                 if (tlb_type == hypervisor)
684                         sun4v_data_access_exception(regs, sfar, sfsr);
685                 else
686                         spitfire_data_access_exception(regs, sfsr, sfar);
687                 return;
688         }
689         advance(regs);
690         return;
691 }