Remove fs.h from mm.h
[linux-2.6] / arch / sparc64 / kernel / unaligned.c
1 /* $Id: unaligned.c,v 1.24 2002/02/09 19:49:31 davem Exp $
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/kernel.h>
11 #include <linux/sched.h>
12 #include <linux/mm.h>
13 #include <linux/module.h>
14 #include <asm/asi.h>
15 #include <asm/ptrace.h>
16 #include <asm/pstate.h>
17 #include <asm/processor.h>
18 #include <asm/system.h>
19 #include <asm/uaccess.h>
20 #include <linux/smp.h>
21 #include <linux/bitops.h>
22 #include <linux/kallsyms.h>
23 #include <asm/fpumacro.h>
24
25 /* #define DEBUG_MNA */
26
27 enum direction {
28         load,    /* ld, ldd, ldh, ldsh */
29         store,   /* st, std, sth, stsh */
30         both,    /* Swap, ldstub, cas, ... */
31         fpld,
32         fpst,
33         invalid,
34 };
35
36 #ifdef DEBUG_MNA
37 static char *dirstrings[] = {
38   "load", "store", "both", "fpload", "fpstore", "invalid"
39 };
40 #endif
41
42 static inline enum direction decode_direction(unsigned int insn)
43 {
44         unsigned long tmp = (insn >> 21) & 1;
45
46         if (!tmp)
47                 return load;
48         else {
49                 switch ((insn>>19)&0xf) {
50                 case 15: /* swap* */
51                         return both;
52                 default:
53                         return store;
54                 }
55         }
56 }
57
58 /* 16 = double-word, 8 = extra-word, 4 = word, 2 = half-word */
59 static inline int decode_access_size(unsigned int insn)
60 {
61         unsigned int tmp;
62
63         tmp = ((insn >> 19) & 0xf);
64         if (tmp == 11 || tmp == 14) /* ldx/stx */
65                 return 8;
66         tmp &= 3;
67         if (!tmp)
68                 return 4;
69         else if (tmp == 3)
70                 return 16;      /* ldd/std - Although it is actually 8 */
71         else if (tmp == 2)
72                 return 2;
73         else {
74                 printk("Impossible unaligned trap. insn=%08x\n", insn);
75                 die_if_kernel("Byte sized unaligned access?!?!", current_thread_info()->kregs);
76
77                 /* GCC should never warn that control reaches the end
78                  * of this function without returning a value because
79                  * die_if_kernel() is marked with attribute 'noreturn'.
80                  * Alas, some versions do...
81                  */
82
83                 return 0;
84         }
85 }
86
87 static inline int decode_asi(unsigned int insn, struct pt_regs *regs)
88 {
89         if (insn & 0x800000) {
90                 if (insn & 0x2000)
91                         return (unsigned char)(regs->tstate >> 24);     /* %asi */
92                 else
93                         return (unsigned char)(insn >> 5);              /* imm_asi */
94         } else
95                 return ASI_P;
96 }
97
98 /* 0x400000 = signed, 0 = unsigned */
99 static inline int decode_signedness(unsigned int insn)
100 {
101         return (insn & 0x400000);
102 }
103
104 static inline void maybe_flush_windows(unsigned int rs1, unsigned int rs2,
105                                        unsigned int rd, int from_kernel)
106 {
107         if (rs2 >= 16 || rs1 >= 16 || rd >= 16) {
108                 if (from_kernel != 0)
109                         __asm__ __volatile__("flushw");
110                 else
111                         flushw_user();
112         }
113 }
114
115 static inline long sign_extend_imm13(long imm)
116 {
117         return imm << 51 >> 51;
118 }
119
120 static unsigned long fetch_reg(unsigned int reg, struct pt_regs *regs)
121 {
122         unsigned long value;
123         
124         if (reg < 16)
125                 return (!reg ? 0 : regs->u_regs[reg]);
126         if (regs->tstate & TSTATE_PRIV) {
127                 struct reg_window *win;
128                 win = (struct reg_window *)(regs->u_regs[UREG_FP] + STACK_BIAS);
129                 value = win->locals[reg - 16];
130         } else if (test_thread_flag(TIF_32BIT)) {
131                 struct reg_window32 __user *win32;
132                 win32 = (struct reg_window32 __user *)((unsigned long)((u32)regs->u_regs[UREG_FP]));
133                 get_user(value, &win32->locals[reg - 16]);
134         } else {
135                 struct reg_window __user *win;
136                 win = (struct reg_window __user *)(regs->u_regs[UREG_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         if (reg < 16)
145                 return &regs->u_regs[reg];
146         if (regs->tstate & TSTATE_PRIV) {
147                 struct reg_window *win;
148                 win = (struct reg_window *)(regs->u_regs[UREG_FP] + STACK_BIAS);
149                 return &win->locals[reg - 16];
150         } else if (test_thread_flag(TIF_32BIT)) {
151                 struct reg_window32 *win32;
152                 win32 = (struct reg_window32 *)((unsigned long)((u32)regs->u_regs[UREG_FP]));
153                 return (unsigned long *)&win32->locals[reg - 16];
154         } else {
155                 struct reg_window *win;
156                 win = (struct reg_window *)(regs->u_regs[UREG_FP] + STACK_BIAS);
157                 return &win->locals[reg - 16];
158         }
159 }
160
161 unsigned long compute_effective_address(struct pt_regs *regs,
162                                         unsigned int insn, unsigned int rd)
163 {
164         unsigned int rs1 = (insn >> 14) & 0x1f;
165         unsigned int rs2 = insn & 0x1f;
166         int from_kernel = (regs->tstate & TSTATE_PRIV) != 0;
167
168         if (insn & 0x2000) {
169                 maybe_flush_windows(rs1, 0, rd, from_kernel);
170                 return (fetch_reg(rs1, regs) + sign_extend_imm13(insn));
171         } else {
172                 maybe_flush_windows(rs1, rs2, rd, from_kernel);
173                 return (fetch_reg(rs1, regs) + fetch_reg(rs2, regs));
174         }
175 }
176
177 /* This is just to make gcc think die_if_kernel does return... */
178 static void __attribute_used__ unaligned_panic(char *str, struct pt_regs *regs)
179 {
180         die_if_kernel(str, regs);
181 }
182
183 extern int do_int_load(unsigned long *dest_reg, int size,
184                        unsigned long *saddr, int is_signed, int asi);
185         
186 extern int __do_int_store(unsigned long *dst_addr, int size,
187                           unsigned long src_val, int asi);
188
189 static inline int do_int_store(int reg_num, int size, unsigned long *dst_addr,
190                                struct pt_regs *regs, int asi, int orig_asi)
191 {
192         unsigned long zero = 0;
193         unsigned long *src_val_p = &zero;
194         unsigned long src_val;
195
196         if (size == 16) {
197                 size = 8;
198                 zero = (((long)(reg_num ?
199                         (unsigned)fetch_reg(reg_num, regs) : 0)) << 32) |
200                         (unsigned)fetch_reg(reg_num + 1, regs);
201         } else if (reg_num) {
202                 src_val_p = fetch_reg_addr(reg_num, regs);
203         }
204         src_val = *src_val_p;
205         if (unlikely(asi != orig_asi)) {
206                 switch (size) {
207                 case 2:
208                         src_val = swab16(src_val);
209                         break;
210                 case 4:
211                         src_val = swab32(src_val);
212                         break;
213                 case 8:
214                         src_val = swab64(src_val);
215                         break;
216                 case 16:
217                 default:
218                         BUG();
219                         break;
220                 };
221         }
222         return __do_int_store(dst_addr, size, src_val, asi);
223 }
224
225 static inline void advance(struct pt_regs *regs)
226 {
227         regs->tpc   = regs->tnpc;
228         regs->tnpc += 4;
229         if (test_thread_flag(TIF_32BIT)) {
230                 regs->tpc &= 0xffffffff;
231                 regs->tnpc &= 0xffffffff;
232         }
233 }
234
235 static inline int floating_point_load_or_store_p(unsigned int insn)
236 {
237         return (insn >> 24) & 1;
238 }
239
240 static inline int ok_for_kernel(unsigned int insn)
241 {
242         return !floating_point_load_or_store_p(insn);
243 }
244
245 static void kernel_mna_trap_fault(int fixup_tstate_asi)
246 {
247         struct pt_regs *regs = current_thread_info()->kern_una_regs;
248         unsigned int insn = current_thread_info()->kern_una_insn;
249         const struct exception_table_entry *entry;
250
251         entry = search_exception_tables(regs->tpc);
252         if (!entry) {
253                 unsigned long address;
254
255                 address = compute_effective_address(regs, insn,
256                                                     ((insn >> 25) & 0x1f));
257                 if (address < PAGE_SIZE) {
258                         printk(KERN_ALERT "Unable to handle kernel NULL "
259                                "pointer dereference in mna handler");
260                 } else
261                         printk(KERN_ALERT "Unable to handle kernel paging "
262                                "request in mna handler");
263                 printk(KERN_ALERT " at virtual address %016lx\n",address);
264                 printk(KERN_ALERT "current->{active_,}mm->context = %016lx\n",
265                         (current->mm ? CTX_HWBITS(current->mm->context) :
266                         CTX_HWBITS(current->active_mm->context)));
267                 printk(KERN_ALERT "current->{active_,}mm->pgd = %016lx\n",
268                         (current->mm ? (unsigned long) current->mm->pgd :
269                         (unsigned long) current->active_mm->pgd));
270                 die_if_kernel("Oops", regs);
271                 /* Not reached */
272         }
273         regs->tpc = entry->fixup;
274         regs->tnpc = regs->tpc + 4;
275
276         if (fixup_tstate_asi) {
277                 regs->tstate &= ~TSTATE_ASI;
278                 regs->tstate |= (ASI_AIUS << 24UL);
279         }
280 }
281
282 static void log_unaligned(struct pt_regs *regs)
283 {
284         static unsigned long count, last_time;
285
286         if (jiffies - last_time > 5 * HZ)
287                 count = 0;
288         if (count < 5) {
289                 last_time = jiffies;
290                 count++;
291                 printk("Kernel unaligned access at TPC[%lx] ", regs->tpc);
292                 print_symbol("%s\n", regs->tpc);
293         }
294 }
295
296 asmlinkage void kernel_unaligned_trap(struct pt_regs *regs, unsigned int insn)
297 {
298         enum direction dir = decode_direction(insn);
299         int size = decode_access_size(insn);
300         int orig_asi, asi;
301
302         current_thread_info()->kern_una_regs = regs;
303         current_thread_info()->kern_una_insn = insn;
304
305         orig_asi = asi = decode_asi(insn, regs);
306
307         /* If this is a {get,put}_user() on an unaligned userspace pointer,
308          * just signal a fault and do not log the event.
309          */
310         if (asi == ASI_AIUS) {
311                 kernel_mna_trap_fault(0);
312                 return;
313         }
314
315         log_unaligned(regs);
316
317         if (!ok_for_kernel(insn) || dir == both) {
318                 printk("Unsupported unaligned load/store trap for kernel "
319                        "at <%016lx>.\n", regs->tpc);
320                 unaligned_panic("Kernel does fpu/atomic "
321                                 "unaligned load/store.", regs);
322
323                 kernel_mna_trap_fault(0);
324         } else {
325                 unsigned long addr, *reg_addr;
326                 int err;
327
328                 addr = compute_effective_address(regs, insn,
329                                                  ((insn >> 25) & 0x1f));
330 #ifdef DEBUG_MNA
331                 printk("KMNA: pc=%016lx [dir=%s addr=%016lx size=%d] "
332                        "retpc[%016lx]\n",
333                        regs->tpc, dirstrings[dir], addr, size,
334                        regs->u_regs[UREG_RETPC]);
335 #endif
336                 switch (asi) {
337                 case ASI_NL:
338                 case ASI_AIUPL:
339                 case ASI_AIUSL:
340                 case ASI_PL:
341                 case ASI_SL:
342                 case ASI_PNFL:
343                 case ASI_SNFL:
344                         asi &= ~0x08;
345                         break;
346                 };
347                 switch (dir) {
348                 case load:
349                         reg_addr = fetch_reg_addr(((insn>>25)&0x1f), regs);
350                         err = do_int_load(reg_addr, size,
351                                           (unsigned long *) addr,
352                                           decode_signedness(insn), asi);
353                         if (likely(!err) && unlikely(asi != orig_asi)) {
354                                 unsigned long val_in = *reg_addr;
355                                 switch (size) {
356                                 case 2:
357                                         val_in = swab16(val_in);
358                                         break;
359                                 case 4:
360                                         val_in = swab32(val_in);
361                                         break;
362                                 case 8:
363                                         val_in = swab64(val_in);
364                                         break;
365                                 case 16:
366                                 default:
367                                         BUG();
368                                         break;
369                                 };
370                                 *reg_addr = val_in;
371                         }
372                         break;
373
374                 case store:
375                         err = do_int_store(((insn>>25)&0x1f), size,
376                                            (unsigned long *) addr, regs,
377                                            asi, orig_asi);
378                         break;
379
380                 default:
381                         panic("Impossible kernel unaligned trap.");
382                         /* Not reached... */
383                 }
384                 if (unlikely(err))
385                         kernel_mna_trap_fault(1);
386                 else
387                         advance(regs);
388         }
389 }
390
391 static char popc_helper[] = {
392 0, 1, 1, 2, 1, 2, 2, 3,
393 1, 2, 2, 3, 2, 3, 3, 4, 
394 };
395
396 int handle_popc(u32 insn, struct pt_regs *regs)
397 {
398         u64 value;
399         int ret, i, rd = ((insn >> 25) & 0x1f);
400         int from_kernel = (regs->tstate & TSTATE_PRIV) != 0;
401                                 
402         if (insn & 0x2000) {
403                 maybe_flush_windows(0, 0, rd, from_kernel);
404                 value = sign_extend_imm13(insn);
405         } else {
406                 maybe_flush_windows(0, insn & 0x1f, rd, from_kernel);
407                 value = fetch_reg(insn & 0x1f, regs);
408         }
409         for (ret = 0, i = 0; i < 16; i++) {
410                 ret += popc_helper[value & 0xf];
411                 value >>= 4;
412         }
413         if (rd < 16) {
414                 if (rd)
415                         regs->u_regs[rd] = ret;
416         } else {
417                 if (test_thread_flag(TIF_32BIT)) {
418                         struct reg_window32 __user *win32;
419                         win32 = (struct reg_window32 __user *)((unsigned long)((u32)regs->u_regs[UREG_FP]));
420                         put_user(ret, &win32->locals[rd - 16]);
421                 } else {
422                         struct reg_window __user *win;
423                         win = (struct reg_window __user *)(regs->u_regs[UREG_FP] + STACK_BIAS);
424                         put_user(ret, &win->locals[rd - 16]);
425                 }
426         }
427         advance(regs);
428         return 1;
429 }
430
431 extern void do_fpother(struct pt_regs *regs);
432 extern void do_privact(struct pt_regs *regs);
433 extern void spitfire_data_access_exception(struct pt_regs *regs,
434                                            unsigned long sfsr,
435                                            unsigned long sfar);
436 extern void sun4v_data_access_exception(struct pt_regs *regs,
437                                         unsigned long addr,
438                                         unsigned long type_ctx);
439
440 int handle_ldf_stq(u32 insn, struct pt_regs *regs)
441 {
442         unsigned long addr = compute_effective_address(regs, insn, 0);
443         int freg = ((insn >> 25) & 0x1e) | ((insn >> 20) & 0x20);
444         struct fpustate *f = FPUSTATE;
445         int asi = decode_asi(insn, regs);
446         int flag = (freg < 32) ? FPRS_DL : FPRS_DU;
447
448         save_and_clear_fpu();
449         current_thread_info()->xfsr[0] &= ~0x1c000;
450         if (freg & 3) {
451                 current_thread_info()->xfsr[0] |= (6 << 14) /* invalid_fp_register */;
452                 do_fpother(regs);
453                 return 0;
454         }
455         if (insn & 0x200000) {
456                 /* STQ */
457                 u64 first = 0, second = 0;
458                 
459                 if (current_thread_info()->fpsaved[0] & flag) {
460                         first = *(u64 *)&f->regs[freg];
461                         second = *(u64 *)&f->regs[freg+2];
462                 }
463                 if (asi < 0x80) {
464                         do_privact(regs);
465                         return 1;
466                 }
467                 switch (asi) {
468                 case ASI_P:
469                 case ASI_S: break;
470                 case ASI_PL:
471                 case ASI_SL: 
472                         {
473                                 /* Need to convert endians */
474                                 u64 tmp = __swab64p(&first);
475                                 
476                                 first = __swab64p(&second);
477                                 second = tmp;
478                                 break;
479                         }
480                 default:
481                         if (tlb_type == hypervisor)
482                                 sun4v_data_access_exception(regs, addr, 0);
483                         else
484                                 spitfire_data_access_exception(regs, 0, addr);
485                         return 1;
486                 }
487                 if (put_user (first >> 32, (u32 __user *)addr) ||
488                     __put_user ((u32)first, (u32 __user *)(addr + 4)) ||
489                     __put_user (second >> 32, (u32 __user *)(addr + 8)) ||
490                     __put_user ((u32)second, (u32 __user *)(addr + 12))) {
491                         if (tlb_type == hypervisor)
492                                 sun4v_data_access_exception(regs, addr, 0);
493                         else
494                                 spitfire_data_access_exception(regs, 0, addr);
495                         return 1;
496                 }
497         } else {
498                 /* LDF, LDDF, LDQF */
499                 u32 data[4] __attribute__ ((aligned(8)));
500                 int size, i;
501                 int err;
502
503                 if (asi < 0x80) {
504                         do_privact(regs);
505                         return 1;
506                 } else if (asi > ASI_SNFL) {
507                         if (tlb_type == hypervisor)
508                                 sun4v_data_access_exception(regs, addr, 0);
509                         else
510                                 spitfire_data_access_exception(regs, 0, addr);
511                         return 1;
512                 }
513                 switch (insn & 0x180000) {
514                 case 0x000000: size = 1; break;
515                 case 0x100000: size = 4; break;
516                 default: size = 2; break;
517                 }
518                 for (i = 0; i < size; i++)
519                         data[i] = 0;
520                 
521                 err = get_user (data[0], (u32 __user *) addr);
522                 if (!err) {
523                         for (i = 1; i < size; i++)
524                                 err |= __get_user (data[i], (u32 __user *)(addr + 4*i));
525                 }
526                 if (err && !(asi & 0x2 /* NF */)) {
527                         if (tlb_type == hypervisor)
528                                 sun4v_data_access_exception(regs, addr, 0);
529                         else
530                                 spitfire_data_access_exception(regs, 0, addr);
531                         return 1;
532                 }
533                 if (asi & 0x8) /* Little */ {
534                         u64 tmp;
535
536                         switch (size) {
537                         case 1: data[0] = le32_to_cpup(data + 0); break;
538                         default:*(u64 *)(data + 0) = le64_to_cpup((u64 *)(data + 0));
539                                 break;
540                         case 4: tmp = le64_to_cpup((u64 *)(data + 0));
541                                 *(u64 *)(data + 0) = le64_to_cpup((u64 *)(data + 2));
542                                 *(u64 *)(data + 2) = tmp;
543                                 break;
544                         }
545                 }
546                 if (!(current_thread_info()->fpsaved[0] & FPRS_FEF)) {
547                         current_thread_info()->fpsaved[0] = FPRS_FEF;
548                         current_thread_info()->gsr[0] = 0;
549                 }
550                 if (!(current_thread_info()->fpsaved[0] & flag)) {
551                         if (freg < 32)
552                                 memset(f->regs, 0, 32*sizeof(u32));
553                         else
554                                 memset(f->regs+32, 0, 32*sizeof(u32));
555                 }
556                 memcpy(f->regs + freg, data, size * 4);
557                 current_thread_info()->fpsaved[0] |= flag;
558         }
559         advance(regs);
560         return 1;
561 }
562
563 void handle_ld_nf(u32 insn, struct pt_regs *regs)
564 {
565         int rd = ((insn >> 25) & 0x1f);
566         int from_kernel = (regs->tstate & TSTATE_PRIV) != 0;
567         unsigned long *reg;
568                                 
569         maybe_flush_windows(0, 0, rd, from_kernel);
570         reg = fetch_reg_addr(rd, regs);
571         if (from_kernel || rd < 16) {
572                 reg[0] = 0;
573                 if ((insn & 0x780000) == 0x180000)
574                         reg[1] = 0;
575         } else if (test_thread_flag(TIF_32BIT)) {
576                 put_user(0, (int __user *) reg);
577                 if ((insn & 0x780000) == 0x180000)
578                         put_user(0, ((int __user *) reg) + 1);
579         } else {
580                 put_user(0, (unsigned long __user *) reg);
581                 if ((insn & 0x780000) == 0x180000)
582                         put_user(0, (unsigned long __user *) reg + 1);
583         }
584         advance(regs);
585 }
586
587 void handle_lddfmna(struct pt_regs *regs, unsigned long sfar, unsigned long sfsr)
588 {
589         unsigned long pc = regs->tpc;
590         unsigned long tstate = regs->tstate;
591         u32 insn;
592         u32 first, second;
593         u64 value;
594         u8 freg;
595         int flag;
596         struct fpustate *f = FPUSTATE;
597
598         if (tstate & TSTATE_PRIV)
599                 die_if_kernel("lddfmna from kernel", regs);
600         if (test_thread_flag(TIF_32BIT))
601                 pc = (u32)pc;
602         if (get_user(insn, (u32 __user *) pc) != -EFAULT) {
603                 int asi = decode_asi(insn, regs);
604                 if ((asi > ASI_SNFL) ||
605                     (asi < ASI_P))
606                         goto daex;
607                 if (get_user(first, (u32 __user *)sfar) ||
608                      get_user(second, (u32 __user *)(sfar + 4))) {
609                         if (asi & 0x2) /* NF */ {
610                                 first = 0; second = 0;
611                         } else
612                                 goto daex;
613                 }
614                 save_and_clear_fpu();
615                 freg = ((insn >> 25) & 0x1e) | ((insn >> 20) & 0x20);
616                 value = (((u64)first) << 32) | second;
617                 if (asi & 0x8) /* Little */
618                         value = __swab64p(&value);
619                 flag = (freg < 32) ? FPRS_DL : FPRS_DU;
620                 if (!(current_thread_info()->fpsaved[0] & FPRS_FEF)) {
621                         current_thread_info()->fpsaved[0] = FPRS_FEF;
622                         current_thread_info()->gsr[0] = 0;
623                 }
624                 if (!(current_thread_info()->fpsaved[0] & flag)) {
625                         if (freg < 32)
626                                 memset(f->regs, 0, 32*sizeof(u32));
627                         else
628                                 memset(f->regs+32, 0, 32*sizeof(u32));
629                 }
630                 *(u64 *)(f->regs + freg) = value;
631                 current_thread_info()->fpsaved[0] |= flag;
632         } else {
633 daex:
634                 if (tlb_type == hypervisor)
635                         sun4v_data_access_exception(regs, sfar, sfsr);
636                 else
637                         spitfire_data_access_exception(regs, sfsr, sfar);
638                 return;
639         }
640         advance(regs);
641         return;
642 }
643
644 void handle_stdfmna(struct pt_regs *regs, unsigned long sfar, unsigned long sfsr)
645 {
646         unsigned long pc = regs->tpc;
647         unsigned long tstate = regs->tstate;
648         u32 insn;
649         u64 value;
650         u8 freg;
651         int flag;
652         struct fpustate *f = FPUSTATE;
653
654         if (tstate & TSTATE_PRIV)
655                 die_if_kernel("stdfmna from kernel", regs);
656         if (test_thread_flag(TIF_32BIT))
657                 pc = (u32)pc;
658         if (get_user(insn, (u32 __user *) pc) != -EFAULT) {
659                 int asi = decode_asi(insn, regs);
660                 freg = ((insn >> 25) & 0x1e) | ((insn >> 20) & 0x20);
661                 value = 0;
662                 flag = (freg < 32) ? FPRS_DL : FPRS_DU;
663                 if ((asi > ASI_SNFL) ||
664                     (asi < ASI_P))
665                         goto daex;
666                 save_and_clear_fpu();
667                 if (current_thread_info()->fpsaved[0] & flag)
668                         value = *(u64 *)&f->regs[freg];
669                 switch (asi) {
670                 case ASI_P:
671                 case ASI_S: break;
672                 case ASI_PL:
673                 case ASI_SL: 
674                         value = __swab64p(&value); break;
675                 default: goto daex;
676                 }
677                 if (put_user (value >> 32, (u32 __user *) sfar) ||
678                     __put_user ((u32)value, (u32 __user *)(sfar + 4)))
679                         goto daex;
680         } else {
681 daex:
682                 if (tlb_type == hypervisor)
683                         sun4v_data_access_exception(regs, sfar, sfsr);
684                 else
685                         spitfire_data_access_exception(regs, sfsr, sfar);
686                 return;
687         }
688         advance(regs);
689         return;
690 }