1 /*-
2 * Copyright (c) 2003 Peter Wemm.
3 * Copyright (c) 1993 The Regents of the University of California.
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 * 3. Neither the name of the University nor the names of its contributors
15 * may be used to endorse or promote products derived from this software
16 * without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 * SUCH DAMAGE.
29 *
30 * $FreeBSD: head/sys/amd64/amd64/support.S 341719 2018-12-08 04:53:08Z mjg $
31 */
32
33 #include "opt_ddb.h"
34
35 #include <machine/asmacros.h>
36 #include <machine/specialreg.h>
37 #include <machine/pmap.h>
38
39 #include "assym.inc"
40
41 .text
42
43 /* Address: %rdi */
44 ENTRY(pagezero_std)
45 PUSH_FRAME_POINTER
46 movq $PAGE_SIZE/8,%rcx
47 xorl %eax,%eax
48 rep
49 stosq
50 POP_FRAME_POINTER
51 ret
52 END(pagezero_std)
53
54 ENTRY(pagezero_erms)
55 PUSH_FRAME_POINTER
56 movq $PAGE_SIZE,%rcx
57 xorl %eax,%eax
58 rep
59 stosb
60 POP_FRAME_POINTER
61 ret
62 END(pagezero_erms)
63
64 /*
65 * pagecopy(%rdi=from, %rsi=to)
66 */
67 ENTRY(pagecopy)
68 PUSH_FRAME_POINTER
69 movq $PAGE_SIZE/8,%rcx
70 movq %rdi,%r9
71 movq %rsi,%rdi
72 movq %r9,%rsi
73 rep
74 movsq
75 POP_FRAME_POINTER
76 ret
77 END(pagecopy)
78
79 /* Address: %rdi */
80 ENTRY(sse2_pagezero)
81 PUSH_FRAME_POINTER
82 movq $-PAGE_SIZE,%rdx
83 subq %rdx,%rdi
84 xorl %eax,%eax
85 jmp 1f
86 /*
87 * The loop takes 29 bytes. Ensure that it doesn't cross a 32-byte
88 * cache line.
89 */
90 .p2align 5,0x90
91 1:
92 movnti %rax,(%rdi,%rdx)
93 movnti %rax,8(%rdi,%rdx)
94 movnti %rax,16(%rdi,%rdx)
95 movnti %rax,24(%rdi,%rdx)
96 addq $32,%rdx
97 jne 1b
98 sfence
99 POP_FRAME_POINTER
100 ret
101 END(sse2_pagezero)
102
103 /*
104 * memcmpy(b1, b2, len)
105 * rdi,rsi,len
106 */
107 ENTRY(memcmp)
108 PUSH_FRAME_POINTER
109 cmpq $16,%rdx
110 jae 5f
111 1:
112 testq %rdx,%rdx
113 je 3f
114 xorl %ecx,%ecx
115 2:
116 movzbl (%rdi,%rcx,1),%eax
117 movzbl (%rsi,%rcx,1),%r8d
118 cmpb %r8b,%al
119 jne 4f
120 addq $1,%rcx
121 cmpq %rcx,%rdx
122 jz 3f
123 movzbl (%rdi,%rcx,1),%eax
124 movzbl (%rsi,%rcx,1),%r8d
125 cmpb %r8b,%al
126 jne 4f
127 addq $1,%rcx
128 cmpq %rcx,%rdx
129 jz 3f
130 movzbl (%rdi,%rcx,1),%eax
131 movzbl (%rsi,%rcx,1),%r8d
132 cmpb %r8b,%al
133 jne 4f
134 addq $1,%rcx
135 cmpq %rcx,%rdx
136 jz 3f
137 movzbl (%rdi,%rcx,1),%eax
138 movzbl (%rsi,%rcx,1),%r8d
139 cmpb %r8b,%al
140 jne 4f
141 addq $1,%rcx
142 cmpq %rcx,%rdx
143 jne 2b
144 3:
145 xorl %eax,%eax
146 POP_FRAME_POINTER
147 ret
148 4:
149 subl %r8d,%eax
150 POP_FRAME_POINTER
151 ret
152 5:
153 cmpq $32,%rdx
154 jae 7f
155 6:
156 /*
157 * 8 bytes
158 */
159 movq (%rdi),%r8
160 movq (%rsi),%r9
161 cmpq %r8,%r9
162 jne 1b
163 leaq 8(%rdi),%rdi
164 leaq 8(%rsi),%rsi
165 subq $8,%rdx
166 cmpq $8,%rdx
167 jae 6b
168 jl 1b
169 jmp 3b
170 7:
171 /*
172 * 32 bytes
173 */
174 movq (%rsi),%r8
175 movq 8(%rsi),%r9
176 subq (%rdi),%r8
177 subq 8(%rdi),%r9
178 or %r8,%r9
179 jnz 1b
180
181 movq 16(%rsi),%r8
182 movq 24(%rsi),%r9
183 subq 16(%rdi),%r8
184 subq 24(%rdi),%r9
185 or %r8,%r9
186 jnz 1b
187
188 leaq 32(%rdi),%rdi
189 leaq 32(%rsi),%rsi
190 subq $32,%rdx
191 cmpq $32,%rdx
192 jae 7b
193 jnz 1b
194 jmp 3b
195 END(memcmp)
196
197 /*
198 * memmove(dst, src, cnt)
199 * rdi, rsi, rdx
200 */
201
202 /*
203 * Register state at entry is supposed to be as follows:
204 * rdi - destination
205 * rsi - source
206 * rdx - count
207 *
208 * The macro possibly clobbers the above and: rcx, r8, r9, 10
209 * It does not clobber rax nor r11.
210 */
211 .macro MEMMOVE erms overlap begin end
212 \begin
213
214 /*
215 * For sizes 0..32 all data is read before it is written, so there
216 * is no correctness issue with direction of copying.
217 */
218 cmpq $32,%rcx
219 jbe 101632f
220
221 .if \overlap == 1
222 movq %rdi,%r8
223 subq %rsi,%r8
224 cmpq %rcx,%r8 /* overlapping && src < dst? */
225 jb 2f
226 .endif
227
228 cmpq $256,%rcx
229 ja 1256f
230
231 103200:
232 movq (%rsi),%rdx
233 movq %rdx,(%rdi)
234 movq 8(%rsi),%rdx
235 movq %rdx,8(%rdi)
236 movq 16(%rsi),%rdx
237 movq %rdx,16(%rdi)
238 movq 24(%rsi),%rdx
239 movq %rdx,24(%rdi)
240 leaq 32(%rsi),%rsi
241 leaq 32(%rdi),%rdi
242 subq $32,%rcx
243 cmpq $32,%rcx
244 jae 103200b
245 cmpb $0,%cl
246 jne 101632f
247 \end
248 ret
249 ALIGN_TEXT
250 101632:
251 cmpb $16,%cl
252 jl 100816f
253 movq (%rsi),%rdx
254 movq 8(%rsi),%r8
255 movq -16(%rsi,%rcx),%r9
256 movq -8(%rsi,%rcx),%r10
257 movq %rdx,(%rdi)
258 movq %r8,8(%rdi)
259 movq %r9,-16(%rdi,%rcx)
260 movq %r10,-8(%rdi,%rcx)
261 \end
262 ret
263 ALIGN_TEXT
264 100816:
265 cmpb $8,%cl
266 jl 100408f
267 movq (%rsi),%rdx
268 movq -8(%rsi,%rcx),%r8
269 movq %rdx,(%rdi)
270 movq %r8,-8(%rdi,%rcx,)
271 \end
272 ret
273 ALIGN_TEXT
274 100408:
275 cmpb $4,%cl
276 jl 100204f
277 movl (%rsi),%edx
278 movl -4(%rsi,%rcx),%r8d
279 movl %edx,(%rdi)
280 movl %r8d,-4(%rdi,%rcx)
281 \end
282 ret
283 ALIGN_TEXT
284 100204:
285 cmpb $2,%cl
286 jl 100001f
287 movzwl (%rsi),%edx
288 movzwl -2(%rsi,%rcx),%r8d
289 movw %dx,(%rdi)
290 movw %r8w,-2(%rdi,%rcx)
291 \end
292 ret
293 ALIGN_TEXT
294 100001:
295 cmpb $1,%cl
296 jl 100000f
297 movb (%rsi),%dl
298 movb %dl,(%rdi)
299 100000:
300 \end
301 ret
302
303 ALIGN_TEXT
304 1256:
305 testb $15,%dil
306 jnz 100f
307 .if \erms == 1
308 rep
309 movsb
310 .else
311 shrq $3,%rcx /* copy by 64-bit words */
312 rep
313 movsq
314 movq %rdx,%rcx
315 andl $7,%ecx /* any bytes left? */
316 jne 100408b
317 .endif
318 \end
319 ret
320 100:
321 movq (%rsi),%r8
322 movq 8(%rsi),%r9
323 movq %rdi,%r10
324 movq %rdi,%rcx
325 andq $15,%rcx
326 leaq -16(%rdx,%rcx),%rdx
327 neg %rcx
328 leaq 16(%rdi,%rcx),%rdi
329 leaq 16(%rsi,%rcx),%rsi
330 movq %rdx,%rcx
331 .if \erms == 1
332 rep
333 movsb
334 movq %r8,(%r10)
335 movq %r9,8(%r10)
336 .else
337 shrq $3,%rcx /* copy by 64-bit words */
338 rep
339 movsq
340 movq %r8,(%r10)
341 movq %r9,8(%r10)
342 movq %rdx,%rcx
343 andl $7,%ecx /* any bytes left? */
344 jne 100408b
345 .endif
346 \end
347 ret
348
349 .if \overlap == 1
350 /*
351 * Copy backwards.
352 */
353 ALIGN_TEXT
354 2:
355 cmpq $256,%rcx
356 ja 2256f
357
358 leaq -8(%rdi,%rcx),%rdi
359 leaq -8(%rsi,%rcx),%rsi
360
361 cmpq $32,%rcx
362 jb 2016f
363
364 2032:
365 movq (%rsi),%rdx
366 movq %rdx,(%rdi)
367 movq -8(%rsi),%rdx
368 movq %rdx,-8(%rdi)
369 movq -16(%rsi),%rdx
370 movq %rdx,-16(%rdi)
371 movq -24(%rsi),%rdx
372 movq %rdx,-24(%rdi)
373 leaq -32(%rsi),%rsi
374 leaq -32(%rdi),%rdi
375 subq $32,%rcx
376 cmpq $32,%rcx
377 jae 2032b
378 cmpb $0,%cl
379 jne 2016f
380 \end
381 ret
382 ALIGN_TEXT
383 2016:
384 cmpb $16,%cl
385 jl 2008f
386 movq (%rsi),%rdx
387 movq %rdx,(%rdi)
388 movq -8(%rsi),%rdx
389 movq %rdx,-8(%rdi)
390 subb $16,%cl
391 jz 2000f
392 leaq -16(%rsi),%rsi
393 leaq -16(%rdi),%rdi
394 2008:
395 cmpb $8,%cl
396 jl 2004f
397 movq (%rsi),%rdx
398 movq %rdx,(%rdi)
399 subb $8,%cl
400 jz 2000f
401 leaq -8(%rsi),%rsi
402 leaq -8(%rdi),%rdi
403 2004:
404 cmpb $4,%cl
405 jl 2002f
406 movl 4(%rsi),%edx
407 movl %edx,4(%rdi)
408 subb $4,%cl
409 jz 2000f
410 leaq -4(%rsi),%rsi
411 leaq -4(%rdi),%rdi
412 2002:
413 cmpb $2,%cl
414 jl 2001f
415 movw 6(%rsi),%dx
416 movw %dx,6(%rdi)
417 subb $2,%cl
418 jz 2000f
419 leaq -2(%rsi),%rsi
420 leaq -2(%rdi),%rdi
421 2001:
422 cmpb $1,%cl
423 jl 2000f
424 movb 7(%rsi),%dl
425 movb %dl,7(%rdi)
426 2000:
427 \end
428 ret
429 ALIGN_TEXT
430 2256:
431 std
432 .if \erms == 1
433 leaq -1(%rdi,%rcx),%rdi
434 leaq -1(%rsi,%rcx),%rsi
435 rep
436 movsb
437 cld
438 .else
439 leaq -8(%rdi,%rcx),%rdi
440 leaq -8(%rsi,%rcx),%rsi
441 shrq $3,%rcx
442 rep
443 movsq
444 cld
445 movq %rdx,%rcx
446 andb $7,%cl
447 jne 2004b
448 .endif
449 \end
450 ret
451 .endif
452 .endm
453
454 .macro MEMMOVE_BEGIN
455 PUSH_FRAME_POINTER
456 movq %rdi,%rax
457 movq %rdx,%rcx
458 .endm
459
460 .macro MEMMOVE_END
461 POP_FRAME_POINTER
462 .endm
463
464 ENTRY(memmove_std)
465 MEMMOVE erms=0 overlap=1 begin=MEMMOVE_BEGIN end=MEMMOVE_END
466 END(memmove_std)
467
468 ENTRY(memmove_erms)
469 MEMMOVE erms=1 overlap=1 begin=MEMMOVE_BEGIN end=MEMMOVE_END
470 END(memmove_erms)
471
472 /*
473 * memcpy(dst, src, len)
474 * rdi, rsi, rdx
475 *
476 * Note: memcpy does not support overlapping copies
477 */
478 ENTRY(memcpy_std)
479 MEMMOVE erms=0 overlap=0 begin=MEMMOVE_BEGIN end=MEMMOVE_END
480 END(memcpy_std)
481
482 ENTRY(memcpy_erms)
483 MEMMOVE erms=1 overlap=0 begin=MEMMOVE_BEGIN end=MEMMOVE_END
484 END(memcpy_erms)
485
486 /*
487 * memset(dst, c, len)
488 * rdi, rsi, rdx
489 */
490 .macro MEMSET erms
491 PUSH_FRAME_POINTER
492 movq %rdi,%rax
493 movq %rdx,%rcx
494 movzbq %sil,%r8
495 movabs $0x0101010101010101,%r10
496 imulq %r8,%r10
497
498 cmpq $32,%rcx
499 jbe 101632f
500
501 cmpq $256,%rcx
502 ja 1256f
503
504 103200:
505 movq %r10,(%rdi)
506 movq %r10,8(%rdi)
507 movq %r10,16(%rdi)
508 movq %r10,24(%rdi)
509 leaq 32(%rdi),%rdi
510 subq $32,%rcx
511 cmpq $32,%rcx
512 ja 103200b
513 cmpb $16,%cl
514 ja 201632f
515 movq %r10,-16(%rdi,%rcx)
516 movq %r10,-8(%rdi,%rcx)
517 POP_FRAME_POINTER
518 ret
519 ALIGN_TEXT
520 101632:
521 cmpb $16,%cl
522 jl 100816f
523 201632:
524 movq %r10,(%rdi)
525 movq %r10,8(%rdi)
526 movq %r10,-16(%rdi,%rcx)
527 movq %r10,-8(%rdi,%rcx)
528 POP_FRAME_POINTER
529 ret
530 ALIGN_TEXT
531 100816:
532 cmpb $8,%cl
533 jl 100408f
534 movq %r10,(%rdi)
535 movq %r10,-8(%rdi,%rcx)
536 POP_FRAME_POINTER
537 ret
538 ALIGN_TEXT
539 100408:
540 cmpb $4,%cl
541 jl 100204f
542 movl %r10d,(%rdi)
543 movl %r10d,-4(%rdi,%rcx)
544 POP_FRAME_POINTER
545 ret
546 ALIGN_TEXT
547 100204:
548 cmpb $2,%cl
549 jl 100001f
550 movw %r10w,(%rdi)
551 movw %r10w,-2(%rdi,%rcx)
552 POP_FRAME_POINTER
553 ret
554 ALIGN_TEXT
555 100001:
556 cmpb $0,%cl
557 je 100000f
558 movb %r10b,(%rdi)
559 100000:
560 POP_FRAME_POINTER
561 ret
562 ALIGN_TEXT
563 1256:
564 movq %rdi,%r9
565 movq %r10,%rax
566 testl $15,%edi
567 jnz 3f
568 1:
569 .if \erms == 1
570 rep
571 stosb
572 movq %r9,%rax
573 .else
574 movq %rcx,%rdx
575 shrq $3,%rcx
576 rep
577 stosq
578 movq %r9,%rax
579 andl $7,%edx
580 jnz 2f
581 POP_FRAME_POINTER
582 ret
583 2:
584 movq %r10,-8(%rdi,%rdx)
585 .endif
586 POP_FRAME_POINTER
587 ret
588 ALIGN_TEXT
589 3:
590 movq %r10,(%rdi)
591 movq %r10,8(%rdi)
592 movq %rdi,%r8
593 andq $15,%r8
594 leaq -16(%rcx,%r8),%rcx
595 neg %r8
596 leaq 16(%rdi,%r8),%rdi
597 jmp 1b
598 .endm
599
600 ENTRY(memset_std)
601 MEMSET erms=0
602 END(memset_std)
603
604 ENTRY(memset_erms)
605 MEMSET erms=1
606 END(memset_erms)
607
608 /* fillw(pat, base, cnt) */
609 /* %rdi,%rsi, %rdx */
610 ENTRY(fillw)
611 PUSH_FRAME_POINTER
612 movq %rdi,%rax
613 movq %rsi,%rdi
614 movq %rdx,%rcx
615 rep
616 stosw
617 POP_FRAME_POINTER
618 ret
619 END(fillw)
620
621 /*****************************************************************************/
622 /* copyout and fubyte family */
623 /*****************************************************************************/
624 /*
625 * Access user memory from inside the kernel. These routines should be
626 * the only places that do this.
627 *
628 * These routines set curpcb->pcb_onfault for the time they execute. When a
629 * protection violation occurs inside the functions, the trap handler
630 * returns to *curpcb->pcb_onfault instead of the function.
631 */
632
633 .macro SMAP_DISABLE smap
634 .if \smap
635 stac
636 .endif
637 .endm
638
639
640 .macro SMAP_ENABLE smap
641 .if \smap
642 clac
643 .endif
644 .endm
645
646 .macro COPYINOUT_BEGIN
647 .endm
648
649 .macro COPYINOUT_END
650 movq %rax,PCB_ONFAULT(%r11)
651 POP_FRAME_POINTER
652 .endm
653
654 .macro COPYINOUT_SMAP_END
655 SMAP_ENABLE smap=1
656 COPYINOUT_END
657 .endm
658
659 /*
660 * copyout(from_kernel, to_user, len)
661 * %rdi, %rsi, %rdx
662 */
663 .macro COPYOUT smap erms
664 PUSH_FRAME_POINTER
665 movq PCPU(CURPCB),%r11
666 movq $copy_fault,PCB_ONFAULT(%r11)
667
668 /*
669 * Check explicitly for non-user addresses. If 486 write protection
670 * is being used, this check is essential because we are in kernel
671 * mode so the h/w does not provide any protection against writing
672 * kernel addresses.
673 */
674
675 /*
676 * First, prevent address wrapping.
677 */
678 movq %rsi,%rax
679 addq %rdx,%rax
680 jc copy_fault
681 /*
682 * XXX STOP USING VM_MAXUSER_ADDRESS.
683 * It is an end address, not a max, so every time it is used correctly it
684 * looks like there is an off by one error, and of course it caused an off
685 * by one error in several places.
686 */
687 movq $VM_MAXUSER_ADDRESS,%rcx
688 cmpq %rcx,%rax
689 ja copy_fault
690
691 /*
692 * Set return value to zero. Remaining failure mode goes through
693 * copy_fault.
694 */
695 xorl %eax,%eax
696
697 /*
698 * Set up arguments for MEMMOVE.
699 */
700 movq %rdi,%r8
701 movq %rsi,%rdi
702 movq %r8,%rsi
703 movq %rdx,%rcx
704
705
706 SMAP_DISABLE \smap
707 .if \smap == 1
708 MEMMOVE erms=\erms overlap=0 begin=COPYINOUT_BEGIN end=COPYINOUT_SMAP_END
709 .else
710 MEMMOVE erms=\erms overlap=0 begin=COPYINOUT_BEGIN end=COPYINOUT_END
711 .endif
712 /* NOTREACHED */
713 .endm
714
715 ENTRY(copyout_nosmap_std)
716 COPYOUT smap=0 erms=0
717 END(copyout_nosmap_std)
718
719 ENTRY(copyout_smap_std)
720 COPYOUT smap=1 erms=0
721 END(copyout_smap_std)
722
723 ENTRY(copyout_nosmap_erms)
724 COPYOUT smap=0 erms=1
725 END(copyout_nosmap_erms)
726
727 ENTRY(copyout_smap_erms)
728 COPYOUT smap=1 erms=1
729 END(copyout_smap_erms)
730
731 /*
732 * copyin(from_user, to_kernel, len)
733 * %rdi, %rsi, %rdx
734 */
735 .macro COPYIN smap erms
736 PUSH_FRAME_POINTER
737 movq PCPU(CURPCB),%r11
738 movq $copy_fault,PCB_ONFAULT(%r11)
739
740 /*
741 * make sure address is valid
742 */
743 movq %rdi,%rax
744 addq %rdx,%rax
745 jc copy_fault
746 movq $VM_MAXUSER_ADDRESS,%rcx
747 cmpq %rcx,%rax
748 ja copy_fault
749
750 xorl %eax,%eax
751
752 movq %rdi,%r8
753 movq %rsi,%rdi
754 movq %r8,%rsi
755 movq %rdx,%rcx
756
757 SMAP_DISABLE \smap
758 .if \smap == 1
759 MEMMOVE erms=\erms overlap=0 begin=COPYINOUT_BEGIN end=COPYINOUT_SMAP_END
760 .else
761 MEMMOVE erms=\erms overlap=0 begin=COPYINOUT_BEGIN end=COPYINOUT_END
762 .endif
763 /* NOTREACHED */
764 .endm
765
766 ENTRY(copyin_nosmap_std)
767 COPYIN smap=0 erms=0
768 END(copyin_nosmap_std)
769
770 ENTRY(copyin_smap_std)
771 COPYIN smap=1 erms=0
772 END(copyin_smap_std)
773
774 ENTRY(copyin_nosmap_erms)
775 COPYIN smap=0 erms=1
776 END(copyin_nosmap_erms)
777
778 ENTRY(copyin_smap_erms)
779 COPYIN smap=1 erms=1
780 END(copyin_smap_erms)
781
782 ALIGN_TEXT
783 /* Trap entry clears PSL.AC */
784 copy_fault:
785 movq $0,PCB_ONFAULT(%r11)
786 movl $EFAULT,%eax
787 POP_FRAME_POINTER
788 ret
789
790 /*
791 * casueword32. Compare and set user integer. Returns -1 on fault,
792 * 0 if access was successful. Old value is written to *oldp.
793 * dst = %rdi, old = %esi, oldp = %rdx, new = %ecx
794 */
795 ENTRY(casueword32_nosmap)
796 PUSH_FRAME_POINTER
797 movq PCPU(CURPCB),%r8
798 movq $fusufault,PCB_ONFAULT(%r8)
799
800 movq $VM_MAXUSER_ADDRESS-4,%rax
801 cmpq %rax,%rdi /* verify address is valid */
802 ja fusufault
803
804 movl %esi,%eax /* old */
805 #ifdef SMP
806 lock
807 #endif
808 cmpxchgl %ecx,(%rdi) /* new = %ecx */
809
810 /*
811 * The old value is in %eax. If the store succeeded it will be the
812 * value we expected (old) from before the store, otherwise it will
813 * be the current value. Save %eax into %esi to prepare the return
814 * value.
815 */
816 movl %eax,%esi
817 xorl %eax,%eax
818 movq %rax,PCB_ONFAULT(%r8)
819
820 /*
821 * Access the oldp after the pcb_onfault is cleared, to correctly
822 * catch corrupted pointer.
823 */
824 movl %esi,(%rdx) /* oldp = %rdx */
825 POP_FRAME_POINTER
826 ret
827 END(casueword32_nosmap)
828
829 ENTRY(casueword32_smap)
830 PUSH_FRAME_POINTER
831 movq PCPU(CURPCB),%r8
832 movq $fusufault,PCB_ONFAULT(%r8)
833
834 movq $VM_MAXUSER_ADDRESS-4,%rax
835 cmpq %rax,%rdi /* verify address is valid */
836 ja fusufault
837
838 movl %esi,%eax /* old */
839 stac
840 #ifdef SMP
841 lock
842 #endif
843 cmpxchgl %ecx,(%rdi) /* new = %ecx */
844 clac
845
846 /*
847 * The old value is in %eax. If the store succeeded it will be the
848 * value we expected (old) from before the store, otherwise it will
849 * be the current value. Save %eax into %esi to prepare the return
850 * value.
851 */
852 movl %eax,%esi
853 xorl %eax,%eax
854 movq %rax,PCB_ONFAULT(%r8)
855
856 /*
857 * Access the oldp after the pcb_onfault is cleared, to correctly
858 * catch corrupted pointer.
859 */
860 movl %esi,(%rdx) /* oldp = %rdx */
861 POP_FRAME_POINTER
862 ret
863 END(casueword32_smap)
864
865 /*
866 * casueword. Compare and set user long. Returns -1 on fault,
867 * 0 if access was successful. Old value is written to *oldp.
868 * dst = %rdi, old = %rsi, oldp = %rdx, new = %rcx
869 */
870 ENTRY(casueword_nosmap)
871 PUSH_FRAME_POINTER
872 movq PCPU(CURPCB),%r8
873 movq $fusufault,PCB_ONFAULT(%r8)
874
875 movq $VM_MAXUSER_ADDRESS-4,%rax
876 cmpq %rax,%rdi /* verify address is valid */
877 ja fusufault
878
879 movq %rsi,%rax /* old */
880 #ifdef SMP
881 lock
882 #endif
883 cmpxchgq %rcx,(%rdi) /* new = %rcx */
884
885 /*
886 * The old value is in %rax. If the store succeeded it will be the
887 * value we expected (old) from before the store, otherwise it will
888 * be the current value.
889 */
890 movq %rax,%rsi
891 xorl %eax,%eax
892 movq %rax,PCB_ONFAULT(%r8)
893 movq %rsi,(%rdx)
894 POP_FRAME_POINTER
895 ret
896 END(casueword_nosmap)
897
898 ENTRY(casueword_smap)
899 PUSH_FRAME_POINTER
900 movq PCPU(CURPCB),%r8
901 movq $fusufault,PCB_ONFAULT(%r8)
902
903 movq $VM_MAXUSER_ADDRESS-4,%rax
904 cmpq %rax,%rdi /* verify address is valid */
905 ja fusufault
906
907 movq %rsi,%rax /* old */
908 stac
909 #ifdef SMP
910 lock
911 #endif
912 cmpxchgq %rcx,(%rdi) /* new = %rcx */
913 clac
914
915 /*
916 * The old value is in %rax. If the store succeeded it will be the
917 * value we expected (old) from before the store, otherwise it will
918 * be the current value.
919 */
920 movq %rax,%rsi
921 xorl %eax,%eax
922 movq %rax,PCB_ONFAULT(%r8)
923 movq %rsi,(%rdx)
924 POP_FRAME_POINTER
925 ret
926 END(casueword_smap)
927
928 /*
929 * Fetch (load) a 64-bit word, a 32-bit word, a 16-bit word, or an 8-bit
930 * byte from user memory.
931 * addr = %rdi, valp = %rsi
932 */
933
934 ENTRY(fueword_nosmap)
935 PUSH_FRAME_POINTER
936 movq PCPU(CURPCB),%rcx
937 movq $fusufault,PCB_ONFAULT(%rcx)
938
939 movq $VM_MAXUSER_ADDRESS-8,%rax
940 cmpq %rax,%rdi /* verify address is valid */
941 ja fusufault
942
943 xorl %eax,%eax
944 movq (%rdi),%r11
945 movq %rax,PCB_ONFAULT(%rcx)
946 movq %r11,(%rsi)
947 POP_FRAME_POINTER
948 ret
949 END(fueword_nosmap)
950
951 ENTRY(fueword_smap)
952 PUSH_FRAME_POINTER
953 movq PCPU(CURPCB),%rcx
954 movq $fusufault,PCB_ONFAULT(%rcx)
955
956 movq $VM_MAXUSER_ADDRESS-8,%rax
957 cmpq %rax,%rdi /* verify address is valid */
958 ja fusufault
959
960 xorl %eax,%eax
961 stac
962 movq (%rdi),%r11
963 clac
964 movq %rax,PCB_ONFAULT(%rcx)
965 movq %r11,(%rsi)
966 POP_FRAME_POINTER
967 ret
968 END(fueword_smap)
969
970 ENTRY(fueword32_nosmap)
971 PUSH_FRAME_POINTER
972 movq PCPU(CURPCB),%rcx
973 movq $fusufault,PCB_ONFAULT(%rcx)
974
975 movq $VM_MAXUSER_ADDRESS-4,%rax
976 cmpq %rax,%rdi /* verify address is valid */
977 ja fusufault
978
979 xorl %eax,%eax
980 movl (%rdi),%r11d
981 movq %rax,PCB_ONFAULT(%rcx)
982 movl %r11d,(%rsi)
983 POP_FRAME_POINTER
984 ret
985 END(fueword32_nosmap)
986
987 ENTRY(fueword32_smap)
988 PUSH_FRAME_POINTER
989 movq PCPU(CURPCB),%rcx
990 movq $fusufault,PCB_ONFAULT(%rcx)
991
992 movq $VM_MAXUSER_ADDRESS-4,%rax
993 cmpq %rax,%rdi /* verify address is valid */
994 ja fusufault
995
996 xorl %eax,%eax
997 stac
998 movl (%rdi),%r11d
999 clac
1000 movq %rax,PCB_ONFAULT(%rcx)
1001 movl %r11d,(%rsi)
1002 POP_FRAME_POINTER
1003 ret
1004 END(fueword32_smap)
1005
1006 ENTRY(fuword16_nosmap)
1007 PUSH_FRAME_POINTER
1008 movq PCPU(CURPCB),%rcx
1009 movq $fusufault,PCB_ONFAULT(%rcx)
1010
1011 movq $VM_MAXUSER_ADDRESS-2,%rax
1012 cmpq %rax,%rdi
1013 ja fusufault
1014
1015 movzwl (%rdi),%eax
1016 movq $0,PCB_ONFAULT(%rcx)
1017 POP_FRAME_POINTER
1018 ret
1019 END(fuword16_nosmap)
1020
1021 ENTRY(fuword16_smap)
1022 PUSH_FRAME_POINTER
1023 movq PCPU(CURPCB),%rcx
1024 movq $fusufault,PCB_ONFAULT(%rcx)
1025
1026 movq $VM_MAXUSER_ADDRESS-2,%rax
1027 cmpq %rax,%rdi
1028 ja fusufault
1029
1030 stac
1031 movzwl (%rdi),%eax
1032 clac
1033 movq $0,PCB_ONFAULT(%rcx)
1034 POP_FRAME_POINTER
1035 ret
1036 END(fuword16_smap)
1037
1038 ENTRY(fubyte_nosmap)
1039 PUSH_FRAME_POINTER
1040 movq PCPU(CURPCB),%rcx
1041 movq $fusufault,PCB_ONFAULT(%rcx)
1042
1043 movq $VM_MAXUSER_ADDRESS-1,%rax
1044 cmpq %rax,%rdi
1045 ja fusufault
1046
1047 movzbl (%rdi),%eax
1048 movq $0,PCB_ONFAULT(%rcx)
1049 POP_FRAME_POINTER
1050 ret
1051 END(fubyte_nosmap)
1052
1053 ENTRY(fubyte_smap)
1054 PUSH_FRAME_POINTER
1055 movq PCPU(CURPCB),%rcx
1056 movq $fusufault,PCB_ONFAULT(%rcx)
1057
1058 movq $VM_MAXUSER_ADDRESS-1,%rax
1059 cmpq %rax,%rdi
1060 ja fusufault
1061
1062 stac
1063 movzbl (%rdi),%eax
1064 clac
1065 movq $0,PCB_ONFAULT(%rcx)
1066 POP_FRAME_POINTER
1067 ret
1068 END(fubyte_smap)
1069
1070 /*
1071 * Store a 64-bit word, a 32-bit word, a 16-bit word, or an 8-bit byte to
1072 * user memory.
1073 * addr = %rdi, value = %rsi
1074 */
1075 ENTRY(suword_nosmap)
1076 PUSH_FRAME_POINTER
1077 movq PCPU(CURPCB),%rcx
1078 movq $fusufault,PCB_ONFAULT(%rcx)
1079
1080 movq $VM_MAXUSER_ADDRESS-8,%rax
1081 cmpq %rax,%rdi /* verify address validity */
1082 ja fusufault
1083
1084 movq %rsi,(%rdi)
1085 xorl %eax,%eax
1086 movq PCPU(CURPCB),%rcx
1087 movq %rax,PCB_ONFAULT(%rcx)
1088 POP_FRAME_POINTER
1089 ret
1090 END(suword_nosmap)
1091
1092 ENTRY(suword_smap)
1093 PUSH_FRAME_POINTER
1094 movq PCPU(CURPCB),%rcx
1095 movq $fusufault,PCB_ONFAULT(%rcx)
1096
1097 movq $VM_MAXUSER_ADDRESS-8,%rax
1098 cmpq %rax,%rdi /* verify address validity */
1099 ja fusufault
1100
1101 stac
1102 movq %rsi,(%rdi)
1103 clac
1104 xorl %eax,%eax
1105 movq PCPU(CURPCB),%rcx
1106 movq %rax,PCB_ONFAULT(%rcx)
1107 POP_FRAME_POINTER
1108 ret
1109 END(suword_smap)
1110
1111 ENTRY(suword32_nosmap)
1112 PUSH_FRAME_POINTER
1113 movq PCPU(CURPCB),%rcx
1114 movq $fusufault,PCB_ONFAULT(%rcx)
1115
1116 movq $VM_MAXUSER_ADDRESS-4,%rax
1117 cmpq %rax,%rdi /* verify address validity */
1118 ja fusufault
1119
1120 movl %esi,(%rdi)
1121 xorl %eax,%eax
1122 movq PCPU(CURPCB),%rcx
1123 movq %rax,PCB_ONFAULT(%rcx)
1124 POP_FRAME_POINTER
1125 ret
1126 END(suword32_nosmap)
1127
1128 ENTRY(suword32_smap)
1129 PUSH_FRAME_POINTER
1130 movq PCPU(CURPCB),%rcx
1131 movq $fusufault,PCB_ONFAULT(%rcx)
1132
1133 movq $VM_MAXUSER_ADDRESS-4,%rax
1134 cmpq %rax,%rdi /* verify address validity */
1135 ja fusufault
1136
1137 stac
1138 movl %esi,(%rdi)
1139 clac
1140 xorl %eax,%eax
1141 movq PCPU(CURPCB),%rcx
1142 movq %rax,PCB_ONFAULT(%rcx)
1143 POP_FRAME_POINTER
1144 ret
1145 END(suword32_smap)
1146
1147 ENTRY(suword16_nosmap)
1148 PUSH_FRAME_POINTER
1149 movq PCPU(CURPCB),%rcx
1150 movq $fusufault,PCB_ONFAULT(%rcx)
1151
1152 movq $VM_MAXUSER_ADDRESS-2,%rax
1153 cmpq %rax,%rdi /* verify address validity */
1154 ja fusufault
1155
1156 movw %si,(%rdi)
1157 xorl %eax,%eax
1158 movq %rax,PCB_ONFAULT(%rcx)
1159 POP_FRAME_POINTER
1160 ret
1161 END(suword16_nosmap)
1162
1163 ENTRY(suword16_smap)
1164 PUSH_FRAME_POINTER
1165 movq PCPU(CURPCB),%rcx
1166 movq $fusufault,PCB_ONFAULT(%rcx)
1167
1168 movq $VM_MAXUSER_ADDRESS-2,%rax
1169 cmpq %rax,%rdi /* verify address validity */
1170 ja fusufault
1171
1172 stac
1173 movw %si,(%rdi)
1174 clac
1175 xorl %eax,%eax
1176 movq %rax,PCB_ONFAULT(%rcx)
1177 POP_FRAME_POINTER
1178 ret
1179 END(suword16_smap)
1180
1181 ENTRY(subyte_nosmap)
1182 PUSH_FRAME_POINTER
1183 movq PCPU(CURPCB),%rcx
1184 movq $fusufault,PCB_ONFAULT(%rcx)
1185
1186 movq $VM_MAXUSER_ADDRESS-1,%rax
1187 cmpq %rax,%rdi /* verify address validity */
1188 ja fusufault
1189
1190 movl %esi,%eax
1191 movb %al,(%rdi)
1192 xorl %eax,%eax
1193 movq %rax,PCB_ONFAULT(%rcx)
1194 POP_FRAME_POINTER
1195 ret
1196 END(subyte_nosmap)
1197
1198 ENTRY(subyte_smap)
1199 PUSH_FRAME_POINTER
1200 movq PCPU(CURPCB),%rcx
1201 movq $fusufault,PCB_ONFAULT(%rcx)
1202
1203 movq $VM_MAXUSER_ADDRESS-1,%rax
1204 cmpq %rax,%rdi /* verify address validity */
1205 ja fusufault
1206
1207 movl %esi,%eax
1208 stac
1209 movb %al,(%rdi)
1210 clac
1211 xorl %eax,%eax
1212 movq %rax,PCB_ONFAULT(%rcx)
1213 POP_FRAME_POINTER
1214 ret
1215 END(subyte_smap)
1216
1217 ALIGN_TEXT
1218 /* Fault entry clears PSL.AC */
1219 fusufault:
1220 movq PCPU(CURPCB),%rcx
1221 xorl %eax,%eax
1222 movq %rax,PCB_ONFAULT(%rcx)
1223 decq %rax
1224 POP_FRAME_POINTER
1225 ret
1226
1227 /*
1228 * copyinstr(from, to, maxlen, int *lencopied)
1229 * %rdi, %rsi, %rdx, %rcx
1230 *
1231 * copy a string from 'from' to 'to', stop when a 0 character is reached.
1232 * return ENAMETOOLONG if string is longer than maxlen, and
1233 * EFAULT on protection violations. If lencopied is non-zero,
1234 * return the actual length in *lencopied.
1235 */
1236 .macro COPYINSTR smap
1237 PUSH_FRAME_POINTER
1238 movq %rdx,%r8 /* %r8 = maxlen */
1239 movq PCPU(CURPCB),%r9
1240 movq $cpystrflt,PCB_ONFAULT(%r9)
1241
1242 movq $VM_MAXUSER_ADDRESS,%rax
1243
1244 /* make sure 'from' is within bounds */
1245 subq %rdi,%rax
1246 jbe cpystrflt
1247
1248 SMAP_DISABLE \smap
1249
1250 /* restrict maxlen to <= VM_MAXUSER_ADDRESS-from */
1251 cmpq %rdx,%rax
1252 jb 8f
1253 1:
1254 incq %rdx
1255 2:
1256 decq %rdx
1257 .if \smap == 0
1258 jz copyinstr_toolong
1259 .else
1260 jz copyinstr_toolong_smap
1261 .endif
1262
1263 movb (%rdi),%al
1264 movb %al,(%rsi)
1265 incq %rsi
1266 incq %rdi
1267 testb %al,%al
1268 jnz 2b
1269
1270 SMAP_ENABLE \smap
1271
1272 /* Success -- 0 byte reached */
1273 decq %rdx
1274 xorl %eax,%eax
1275
1276 /* set *lencopied and return %eax */
1277 movq %rax,PCB_ONFAULT(%r9)
1278
1279 testq %rcx,%rcx
1280 jz 3f
1281 subq %rdx,%r8
1282 movq %r8,(%rcx)
1283 3:
1284 POP_FRAME_POINTER
1285 ret
1286 ALIGN_TEXT
1287 8:
1288 movq %rax,%rdx
1289 movq %rax,%r8
1290 jmp 1b
1291
1292 .endm
1293
1294 ENTRY(copyinstr_nosmap)
1295 COPYINSTR smap=0
1296 END(copyinstr_nosmap)
1297
1298 ENTRY(copyinstr_smap)
1299 COPYINSTR smap=1
1300 END(copyinstr_smap)
1301
1302 cpystrflt:
1303 /* Fault entry clears PSL.AC */
1304 movl $EFAULT,%eax
1305 cpystrflt_x:
1306 /* set *lencopied and return %eax */
1307 movq $0,PCB_ONFAULT(%r9)
1308
1309 testq %rcx,%rcx
1310 jz 1f
1311 subq %rdx,%r8
1312 movq %r8,(%rcx)
1313 1:
1314 POP_FRAME_POINTER
1315 ret
1316
1317 copyinstr_toolong_smap:
1318 clac
1319 copyinstr_toolong:
1320 /* rdx is zero - return ENAMETOOLONG or EFAULT */
1321 movq $VM_MAXUSER_ADDRESS,%rax
1322 cmpq %rax,%rdi
1323 jae cpystrflt
1324 movl $ENAMETOOLONG,%eax
1325 jmp cpystrflt_x
1326
1327 /*
1328 * copystr(from, to, maxlen, int *lencopied)
1329 * %rdi, %rsi, %rdx, %rcx
1330 */
1331 ENTRY(copystr)
1332 PUSH_FRAME_POINTER
1333 movq %rdx,%r8 /* %r8 = maxlen */
1334
1335 incq %rdx
1336 1:
1337 decq %rdx
1338 jz 4f
1339 movb (%rdi),%al
1340 movb %al,(%rsi)
1341 incq %rsi
1342 incq %rdi
1343 testb %al,%al
1344 jnz 1b
1345
1346 /* Success -- 0 byte reached */
1347 decq %rdx
1348 xorl %eax,%eax
1349 2:
1350 testq %rcx,%rcx
1351 jz 3f
1352 /* set *lencopied and return %rax */
1353 subq %rdx,%r8
1354 movq %r8,(%rcx)
1355 3:
1356 POP_FRAME_POINTER
1357 ret
1358 4:
1359 /* rdx is zero -- return ENAMETOOLONG */
1360 movl $ENAMETOOLONG,%eax
1361 jmp 2b
1362 END(copystr)
1363
1364 /*
1365 * Handling of special amd64 registers and descriptor tables etc
1366 */
1367 /* void lgdt(struct region_descriptor *rdp); */
1368 ENTRY(lgdt)
1369 /* reload the descriptor table */
1370 lgdt (%rdi)
1371
1372 /* flush the prefetch q */
1373 jmp 1f
1374 nop
1375 1:
1376 movl $KDSEL,%eax
1377 movl %eax,%ds
1378 movl %eax,%es
1379 movl %eax,%fs /* Beware, use wrmsr to set 64 bit base */
1380 movl %eax,%gs
1381 movl %eax,%ss
1382
1383 /* reload code selector by turning return into intersegmental return */
1384 popq %rax
1385 pushq $KCSEL
1386 pushq %rax
1387 MEXITCOUNT
1388 lretq
1389 END(lgdt)
1390
1391 /*****************************************************************************/
1392 /* setjump, longjump */
1393 /*****************************************************************************/
1394
1395 ENTRY(setjmp)
1396 movq %rbx,0(%rdi) /* save rbx */
1397 movq %rsp,8(%rdi) /* save rsp */
1398 movq %rbp,16(%rdi) /* save rbp */
1399 movq %r12,24(%rdi) /* save r12 */
1400 movq %r13,32(%rdi) /* save r13 */
1401 movq %r14,40(%rdi) /* save r14 */
1402 movq %r15,48(%rdi) /* save r15 */
1403 movq 0(%rsp),%rdx /* get rta */
1404 movq %rdx,56(%rdi) /* save rip */
1405 xorl %eax,%eax /* return(0); */
1406 ret
1407 END(setjmp)
1408
1409 ENTRY(longjmp)
1410 movq 0(%rdi),%rbx /* restore rbx */
1411 movq 8(%rdi),%rsp /* restore rsp */
1412 movq 16(%rdi),%rbp /* restore rbp */
1413 movq 24(%rdi),%r12 /* restore r12 */
1414 movq 32(%rdi),%r13 /* restore r13 */
1415 movq 40(%rdi),%r14 /* restore r14 */
1416 movq 48(%rdi),%r15 /* restore r15 */
1417 movq 56(%rdi),%rdx /* get rta */
1418 movq %rdx,0(%rsp) /* put in return frame */
1419 xorl %eax,%eax /* return(1); */
1420 incl %eax
1421 ret
1422 END(longjmp)
1423
1424 /*
1425 * Support for reading MSRs in the safe manner. (Instead of panic on #gp,
1426 * return an error.)
1427 */
1428 ENTRY(rdmsr_safe)
1429 /* int rdmsr_safe(u_int msr, uint64_t *data) */
1430 PUSH_FRAME_POINTER
1431 movq PCPU(CURPCB),%r8
1432 movq $msr_onfault,PCB_ONFAULT(%r8)
1433 movl %edi,%ecx
1434 rdmsr /* Read MSR pointed by %ecx. Returns
1435 hi byte in edx, lo in %eax */
1436 salq $32,%rdx /* sign-shift %rdx left */
1437 movl %eax,%eax /* zero-extend %eax -> %rax */
1438 orq %rdx,%rax
1439 movq %rax,(%rsi)
1440 xorq %rax,%rax
1441 movq %rax,PCB_ONFAULT(%r8)
1442 POP_FRAME_POINTER
1443 ret
1444
1445 /*
1446 * Support for writing MSRs in the safe manner. (Instead of panic on #gp,
1447 * return an error.)
1448 */
1449 ENTRY(wrmsr_safe)
1450 /* int wrmsr_safe(u_int msr, uint64_t data) */
1451 PUSH_FRAME_POINTER
1452 movq PCPU(CURPCB),%r8
1453 movq $msr_onfault,PCB_ONFAULT(%r8)
1454 movl %edi,%ecx
1455 movl %esi,%eax
1456 sarq $32,%rsi
1457 movl %esi,%edx
1458 wrmsr /* Write MSR pointed by %ecx. Accepts
1459 hi byte in edx, lo in %eax. */
1460 xorq %rax,%rax
1461 movq %rax,PCB_ONFAULT(%r8)
1462 POP_FRAME_POINTER
1463 ret
1464
1465 /*
1466 * MSR operations fault handler
1467 */
1468 ALIGN_TEXT
1469 msr_onfault:
1470 movq $0,PCB_ONFAULT(%r8)
1471 movl $EFAULT,%eax
1472 POP_FRAME_POINTER
1473 ret
1474
1475 /*
1476 * void pmap_pti_pcid_invalidate(uint64_t ucr3, uint64_t kcr3);
1477 * Invalidates address space addressed by ucr3, then returns to kcr3.
1478 * Done in assembler to ensure no other memory accesses happen while
1479 * on ucr3.
1480 */
1481 ALIGN_TEXT
1482 ENTRY(pmap_pti_pcid_invalidate)
1483 pushfq
1484 cli
1485 movq %rdi,%cr3 /* to user page table */
1486 movq %rsi,%cr3 /* back to kernel */
1487 popfq
1488 retq
1489
1490 /*
1491 * void pmap_pti_pcid_invlpg(uint64_t ucr3, uint64_t kcr3, vm_offset_t va);
1492 * Invalidates virtual address va in address space ucr3, then returns to kcr3.
1493 */
1494 ALIGN_TEXT
1495 ENTRY(pmap_pti_pcid_invlpg)
1496 pushfq
1497 cli
1498 movq %rdi,%cr3 /* to user page table */
1499 invlpg (%rdx)
1500 movq %rsi,%cr3 /* back to kernel */
1501 popfq
1502 retq
1503
1504 /*
1505 * void pmap_pti_pcid_invlrng(uint64_t ucr3, uint64_t kcr3, vm_offset_t sva,
1506 * vm_offset_t eva);
1507 * Invalidates virtual addresses between sva and eva in address space ucr3,
1508 * then returns to kcr3.
1509 */
1510 ALIGN_TEXT
1511 ENTRY(pmap_pti_pcid_invlrng)
1512 pushfq
1513 cli
1514 movq %rdi,%cr3 /* to user page table */
1515 1: invlpg (%rdx)
1516 addq $PAGE_SIZE,%rdx
1517 cmpq %rdx,%rcx
1518 ja 1b
1519 movq %rsi,%cr3 /* back to kernel */
1520 popfq
1521 retq
1522
1523 .altmacro
1524 .macro ibrs_seq_label l
1525 handle_ibrs_\l:
1526 .endm
1527 .macro ibrs_call_label l
1528 call handle_ibrs_\l
1529 .endm
1530 .macro ibrs_seq count
1531 ll=1
1532 .rept \count
1533 ibrs_call_label %(ll)
1534 nop
1535 ibrs_seq_label %(ll)
1536 addq $8,%rsp
1537 ll=ll+1
1538 .endr
1539 .endm
1540
1541 /* all callers already saved %rax, %rdx, and %rcx */
1542 ENTRY(handle_ibrs_entry)
1543 cmpb $0,hw_ibrs_active(%rip)
1544 je 1f
1545 movl $MSR_IA32_SPEC_CTRL,%ecx
1546 rdmsr
1547 orl $(IA32_SPEC_CTRL_IBRS|IA32_SPEC_CTRL_STIBP),%eax
1548 orl $(IA32_SPEC_CTRL_IBRS|IA32_SPEC_CTRL_STIBP)>>32,%edx
1549 wrmsr
1550 movb $1,PCPU(IBPB_SET)
1551 testl $CPUID_STDEXT_SMEP,cpu_stdext_feature(%rip)
1552 jne 1f
1553 ibrs_seq 32
1554 1: ret
1555 END(handle_ibrs_entry)
1556
1557 ENTRY(handle_ibrs_exit)
1558 cmpb $0,PCPU(IBPB_SET)
1559 je 1f
1560 movl $MSR_IA32_SPEC_CTRL,%ecx
1561 rdmsr
1562 andl $~(IA32_SPEC_CTRL_IBRS|IA32_SPEC_CTRL_STIBP),%eax
1563 andl $~((IA32_SPEC_CTRL_IBRS|IA32_SPEC_CTRL_STIBP)>>32),%edx
1564 wrmsr
1565 movb $0,PCPU(IBPB_SET)
1566 1: ret
1567 END(handle_ibrs_exit)
1568
1569 /* registers-neutral version, but needs stack */
1570 ENTRY(handle_ibrs_exit_rs)
1571 cmpb $0,PCPU(IBPB_SET)
1572 je 1f
1573 pushq %rax
1574 pushq %rdx
1575 pushq %rcx
1576 movl $MSR_IA32_SPEC_CTRL,%ecx
1577 rdmsr
1578 andl $~(IA32_SPEC_CTRL_IBRS|IA32_SPEC_CTRL_STIBP),%eax
1579 andl $~((IA32_SPEC_CTRL_IBRS|IA32_SPEC_CTRL_STIBP)>>32),%edx
1580 wrmsr
1581 popq %rcx
1582 popq %rdx
1583 popq %rax
1584 movb $0,PCPU(IBPB_SET)
1585 1: ret
1586 END(handle_ibrs_exit_rs)
1587
1588 .noaltmacro
1589
1590 /*
1591 * Flush L1D cache. Load enough of the data from the kernel text
1592 * to flush existing L1D content.
1593 *
1594 * N.B. The function does not follow ABI calling conventions, it corrupts %rbx.
1595 * The vmm.ko caller expects that only %rax, %rdx, %rbx, %rcx, %r9, and %rflags
1596 * registers are clobbered. The NMI handler caller only needs %r13 preserved.
1597 */
1598 ENTRY(flush_l1d_sw)
1599 #define L1D_FLUSH_SIZE (64 * 1024)
1600 movq $KERNBASE, %r9
1601 movq $-L1D_FLUSH_SIZE, %rcx
1602 /*
1603 * pass 1: Preload TLB.
1604 * Kernel text is mapped using superpages. TLB preload is
1605 * done for the benefit of older CPUs which split 2M page
1606 * into 4k TLB entries.
1607 */
1608 1: movb L1D_FLUSH_SIZE(%r9, %rcx), %al
1609 addq $PAGE_SIZE, %rcx
1610 jne 1b
1611 xorl %eax, %eax
1612 cpuid
1613 movq $-L1D_FLUSH_SIZE, %rcx
1614 /* pass 2: Read each cache line. */
1615 2: movb L1D_FLUSH_SIZE(%r9, %rcx), %al
1616 addq $64, %rcx
1617 jne 2b
1618 lfence
1619 ret
1620 #undef L1D_FLUSH_SIZE
1621 END(flush_l1d_sw)
1622
1623 ENTRY(flush_l1d_sw_abi)
1624 pushq %rbx
1625 call flush_l1d_sw
1626 popq %rbx
1627 ret
1628 END(flush_l1d_sw_abi)
Cache object: fa78a34059161e4f7f360df3b956aa68
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