xref: /illumos-gate/usr/src/uts/sun4/vm/vm_dep.c (revision 10a404923096d60a26c785c3cee15a5c364d51c0)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 /*
27  * UNIX machine dependent virtual memory support.
28  */
29 
30 #include <sys/vm.h>
31 #include <sys/exec.h>
32 
33 #include <sys/exechdr.h>
34 #include <vm/seg_kmem.h>
35 #include <sys/atomic.h>
36 #include <sys/archsystm.h>
37 #include <sys/machsystm.h>
38 #include <sys/kdi.h>
39 #include <sys/cpu_module.h>
40 #include <sys/secflags.h>
41 
42 #include <vm/hat_sfmmu.h>
43 
44 #include <sys/memnode.h>
45 
46 #include <sys/mem_config.h>
47 #include <sys/mem_cage.h>
48 #include <vm/vm_dep.h>
49 #include <vm/page.h>
50 #include <sys/platform_module.h>
51 
52 /*
53  * These variables are set by module specific config routines.
54  * They are only set by modules which will use physical cache page coloring.
55  */
56 int do_pg_coloring = 0;
57 
58 /*
59  * These variables can be conveniently patched at kernel load time to
60  * prevent do_pg_coloring from being enabled by
61  * module specific config routines.
62  */
63 
64 int use_page_coloring = 1;
65 
66 /*
67  * initialized by page_coloring_init()
68  */
69 extern uint_t page_colors;
70 extern uint_t page_colors_mask;
71 extern uint_t page_coloring_shift;
72 int cpu_page_colors;
73 uint_t vac_colors = 0;
74 uint_t vac_colors_mask = 0;
75 
76 /* cpu specific coloring initialization */
77 extern void page_coloring_init_cpu();
78 #pragma weak page_coloring_init_cpu
79 
80 /*
81  * get the ecache setsize for the current cpu.
82  */
83 #define	CPUSETSIZE()	(cpunodes[CPU->cpu_id].ecache_setsize)
84 
85 plcnt_t		plcnt;		/* page list count */
86 
87 /*
88  * This variable is set by the cpu module to contain the lowest
89  * address not affected by the SF_ERRATA_57 workaround.  It should
90  * remain 0 if the workaround is not needed.
91  */
92 #if defined(SF_ERRATA_57)
93 caddr_t errata57_limit;
94 #endif
95 
96 extern void page_relocate_hash(page_t *, page_t *);
97 
98 /*
99  * these must be defined in platform specific areas
100  */
101 extern void map_addr_proc(caddr_t *, size_t, offset_t, int, caddr_t,
102 	struct proc *, uint_t);
103 extern page_t *page_get_freelist(struct vnode *, u_offset_t, struct seg *,
104 	caddr_t, size_t, uint_t, struct lgrp *);
105 /*
106  * Convert page frame number to an OBMEM page frame number
107  * (i.e. put in the type bits -- zero for this implementation)
108  */
109 pfn_t
110 impl_obmem_pfnum(pfn_t pf)
111 {
112 	return (pf);
113 }
114 
115 /*
116  * Use physmax to determine the highest physical page of DRAM memory
117  * It is assumed that any physical addresses above physmax is in IO space.
118  * We don't bother checking the low end because we assume that memory space
119  * begins at physical page frame 0.
120  *
121  * Return 1 if the page frame is onboard DRAM memory, else 0.
122  * Returns 0 for nvram so it won't be cached.
123  */
124 int
125 pf_is_memory(pfn_t pf)
126 {
127 	/* We must be IO space */
128 	if (pf > physmax)
129 		return (0);
130 
131 	/* We must be memory space */
132 	return (1);
133 }
134 
135 /*
136  * Handle a pagefault.
137  */
138 faultcode_t
139 pagefault(caddr_t addr, enum fault_type type, enum seg_rw rw, int iskernel)
140 {
141 	struct as *as;
142 	struct proc *p;
143 	faultcode_t res;
144 	caddr_t base;
145 	size_t len;
146 	int err;
147 
148 	if (INVALID_VADDR(addr))
149 		return (FC_NOMAP);
150 
151 	if (iskernel) {
152 		as = &kas;
153 	} else {
154 		p = curproc;
155 		as = p->p_as;
156 #if defined(SF_ERRATA_57)
157 		/*
158 		 * Prevent infinite loops due to a segment driver
159 		 * setting the execute permissions and the sfmmu hat
160 		 * silently ignoring them.
161 		 */
162 		if (rw == S_EXEC && AS_TYPE_64BIT(as) &&
163 		    addr < errata57_limit) {
164 			res = FC_NOMAP;
165 			goto out;
166 		}
167 #endif
168 	}
169 
170 	/*
171 	 * Dispatch pagefault.
172 	 */
173 	res = as_fault(as->a_hat, as, addr, 1, type, rw);
174 
175 	/*
176 	 * If this isn't a potential unmapped hole in the user's
177 	 * UNIX data or stack segments, just return status info.
178 	 */
179 	if (!(res == FC_NOMAP && iskernel == 0))
180 		goto out;
181 
182 	/*
183 	 * Check to see if we happened to faulted on a currently unmapped
184 	 * part of the UNIX data or stack segments.  If so, create a zfod
185 	 * mapping there and then try calling the fault routine again.
186 	 */
187 	base = p->p_brkbase;
188 	len = p->p_brksize;
189 
190 	if (addr < base || addr >= base + len) {		/* data seg? */
191 		base = (caddr_t)(p->p_usrstack - p->p_stksize);
192 		len = p->p_stksize;
193 		if (addr < base || addr >= p->p_usrstack) {	/* stack seg? */
194 			/* not in either UNIX data or stack segments */
195 			res = FC_NOMAP;
196 			goto out;
197 		}
198 	}
199 
200 	/* the rest of this function implements a 3.X 4.X 5.X compatibility */
201 	/* This code is probably not needed anymore */
202 
203 	/* expand the gap to the page boundaries on each side */
204 	len = (((uintptr_t)base + len + PAGEOFFSET) & PAGEMASK) -
205 	    ((uintptr_t)base & PAGEMASK);
206 	base = (caddr_t)((uintptr_t)base & PAGEMASK);
207 
208 	as_rangelock(as);
209 	as_purge(as);
210 	if (as_gap(as, PAGESIZE, &base, &len, AH_CONTAIN, addr) == 0) {
211 		err = as_map(as, base, len, segvn_create, zfod_argsp);
212 		as_rangeunlock(as);
213 		if (err) {
214 			res = FC_MAKE_ERR(err);
215 			goto out;
216 		}
217 	} else {
218 		/*
219 		 * This page is already mapped by another thread after we
220 		 * returned from as_fault() above.  We just fallthrough
221 		 * as_fault() below.
222 		 */
223 		as_rangeunlock(as);
224 	}
225 
226 	res = as_fault(as->a_hat, as, addr, 1, F_INVAL, rw);
227 
228 out:
229 
230 	return (res);
231 }
232 
233 /*
234  * This is the routine which defines the address limit implied
235  * by the flag '_MAP_LOW32'.  USERLIMIT32 matches the highest
236  * mappable address in a 32-bit process on this platform (though
237  * perhaps we should make it be UINT32_MAX here?)
238  */
239 void
240 map_addr(caddr_t *addrp, size_t len, offset_t off, int vacalign, uint_t flags)
241 {
242 	struct proc *p = curproc;
243 	caddr_t userlimit = flags & _MAP_LOW32 ?
244 	    (caddr_t)USERLIMIT32 : p->p_as->a_userlimit;
245 	map_addr_proc(addrp, len, off, vacalign, userlimit, p, flags);
246 }
247 
248 /*
249  * Some V9 CPUs have holes in the middle of the 64-bit virtual address range.
250  */
251 caddr_t	hole_start, hole_end;
252 
253 /*
254  * kpm mapping window
255  */
256 caddr_t kpm_vbase;
257 size_t  kpm_size;
258 uchar_t kpm_size_shift;
259 
260 int valid_va_range_aligned_wraparound;
261 /*
262  * Determine whether [*basep, *basep + *lenp) contains a mappable range of
263  * addresses at least "minlen" long, where the base of the range is at "off"
264  * phase from an "align" boundary and there is space for a "redzone"-sized
265  * redzone on either side of the range.  On success, 1 is returned and *basep
266  * and *lenp are adjusted to describe the acceptable range (including
267  * the redzone).  On failure, 0 is returned.
268  */
269 int
270 valid_va_range_aligned(caddr_t *basep, size_t *lenp, size_t minlen, int dir,
271     size_t align, size_t redzone, size_t off)
272 {
273 	caddr_t hi, lo;
274 	size_t tot_len;
275 
276 	ASSERT(align == 0 ? off == 0 : off < align);
277 	ASSERT(ISP2(align));
278 	ASSERT(align == 0 || align >= PAGESIZE);
279 
280 	lo = *basep;
281 	hi = lo + *lenp;
282 	tot_len = minlen + 2 * redzone;	/* need at least this much space */
283 
284 	/* If hi rolled over the top try cutting back. */
285 	if (hi < lo) {
286 		*lenp = 0UL - (uintptr_t)lo - 1UL;
287 		/* Trying to see if this really happens, and then if so, why */
288 		valid_va_range_aligned_wraparound++;
289 		hi = lo + *lenp;
290 	}
291 	if (*lenp < tot_len) {
292 		return (0);
293 	}
294 
295 	/*
296 	 * Deal with a possible hole in the address range between
297 	 * hole_start and hole_end that should never be mapped by the MMU.
298 	 */
299 
300 	if (lo < hole_start) {
301 		if (hi > hole_start)
302 			if (hi < hole_end)
303 				hi = hole_start;
304 			else
305 				/* lo < hole_start && hi >= hole_end */
306 				if (dir == AH_LO) {
307 					/*
308 					 * prefer lowest range
309 					 */
310 					if (hole_start - lo >= tot_len)
311 						hi = hole_start;
312 					else if (hi - hole_end >= tot_len)
313 						lo = hole_end;
314 					else
315 						return (0);
316 				} else {
317 					/*
318 					 * prefer highest range
319 					 */
320 					if (hi - hole_end >= tot_len)
321 						lo = hole_end;
322 					else if (hole_start - lo >= tot_len)
323 						hi = hole_start;
324 					else
325 						return (0);
326 				}
327 	} else {
328 		/* lo >= hole_start */
329 		if (hi < hole_end)
330 			return (0);
331 		if (lo < hole_end)
332 			lo = hole_end;
333 	}
334 
335 	/* Check if remaining length is too small */
336 	if (hi - lo < tot_len) {
337 		return (0);
338 	}
339 	if (align > 1) {
340 		caddr_t tlo = lo + redzone;
341 		caddr_t thi = hi - redzone;
342 		tlo = (caddr_t)P2PHASEUP((uintptr_t)tlo, align, off);
343 		if (tlo < lo + redzone) {
344 			return (0);
345 		}
346 		if (thi < tlo || thi - tlo < minlen) {
347 			return (0);
348 		}
349 	}
350 	*basep = lo;
351 	*lenp = hi - lo;
352 	return (1);
353 }
354 
355 /*
356  * Determine whether [*basep, *basep + *lenp) contains a mappable range of
357  * addresses at least "minlen" long.  On success, 1 is returned and *basep
358  * and *lenp are adjusted to describe the acceptable range.  On failure, 0
359  * is returned.
360  */
361 int
362 valid_va_range(caddr_t *basep, size_t *lenp, size_t minlen, int dir)
363 {
364 	return (valid_va_range_aligned(basep, lenp, minlen, dir, 0, 0, 0));
365 }
366 
367 /*
368  * Default to forbidding the first 64k of address space.  This protects most
369  * reasonably sized structures from dereferences through NULL:
370  *     ((foo_t *)0)->bar
371  */
372 uintptr_t forbidden_null_mapping_sz = 0x10000;
373 
374 /*
375  * Determine whether [addr, addr+len] with protections `prot' are valid
376  * for a user address space.
377  */
378 /*ARGSUSED*/
379 int
380 valid_usr_range(caddr_t addr, size_t len, uint_t prot, struct as *as,
381     caddr_t userlimit)
382 {
383 	caddr_t eaddr = addr + len;
384 
385 	if (eaddr <= addr || addr >= userlimit || eaddr > userlimit)
386 		return (RANGE_BADADDR);
387 
388 	if ((addr <= (caddr_t)forbidden_null_mapping_sz) &&
389 	    secflag_enabled(as->a_proc, PROC_SEC_FORBIDNULLMAP))
390 		return (RANGE_BADADDR);
391 
392 	/*
393 	 * Determine if the address range falls within an illegal
394 	 * range of the MMU.
395 	 */
396 	if (eaddr > hole_start && addr < hole_end)
397 		return (RANGE_BADADDR);
398 
399 #if defined(SF_ERRATA_57)
400 	/*
401 	 * Make sure USERLIMIT isn't raised too high
402 	 */
403 	ASSERT64(addr <= (caddr_t)0xffffffff80000000ul ||
404 	    errata57_limit == 0);
405 
406 	if (AS_TYPE_64BIT(as) &&
407 	    (addr < errata57_limit) &&
408 	    (prot & PROT_EXEC))
409 		return (RANGE_BADPROT);
410 #endif /* SF_ERRATA57 */
411 	return (RANGE_OKAY);
412 }
413 
414 /*
415  * Routine used to check to see if an a.out can be executed
416  * by the current machine/architecture.
417  */
418 int
419 chkaout(struct exdata *exp)
420 {
421 	if (exp->ux_mach == M_SPARC)
422 		return (0);
423 	else
424 		return (ENOEXEC);
425 }
426 
427 /*
428  * The following functions return information about an a.out
429  * which is used when a program is executed.
430  */
431 
432 /*
433  * Return the load memory address for the data segment.
434  */
435 caddr_t
436 getdmem(struct exec *exp)
437 {
438 	/*
439 	 * XXX - Sparc Reference Hack approaching
440 	 * Remember that we are loading
441 	 * 8k executables into a 4k machine
442 	 * DATA_ALIGN == 2 * PAGESIZE
443 	 */
444 	if (exp->a_text)
445 		return ((caddr_t)(roundup(USRTEXT + exp->a_text, DATA_ALIGN)));
446 	else
447 		return ((caddr_t)USRTEXT);
448 }
449 
450 /*
451  * Return the starting disk address for the data segment.
452  */
453 ulong_t
454 getdfile(struct exec *exp)
455 {
456 	if (exp->a_magic == ZMAGIC)
457 		return (exp->a_text);
458 	else
459 		return (sizeof (struct exec) + exp->a_text);
460 }
461 
462 /*
463  * Return the load memory address for the text segment.
464  */
465 
466 /*ARGSUSED*/
467 caddr_t
468 gettmem(struct exec *exp)
469 {
470 	return ((caddr_t)USRTEXT);
471 }
472 
473 /*
474  * Return the file byte offset for the text segment.
475  */
476 uint_t
477 gettfile(struct exec *exp)
478 {
479 	if (exp->a_magic == ZMAGIC)
480 		return (0);
481 	else
482 		return (sizeof (struct exec));
483 }
484 
485 void
486 getexinfo(
487 	struct exdata *edp_in,
488 	struct exdata *edp_out,
489 	int *pagetext,
490 	int *pagedata)
491 {
492 	*edp_out = *edp_in;	/* structure copy */
493 
494 	if ((edp_in->ux_mag == ZMAGIC) &&
495 	    ((edp_in->vp->v_flag & VNOMAP) == 0)) {
496 		*pagetext = 1;
497 		*pagedata = 1;
498 	} else {
499 		*pagetext = 0;
500 		*pagedata = 0;
501 	}
502 }
503 
504 /*
505  * Return non 0 value if the address may cause a VAC alias with KPM mappings.
506  * KPM selects an address such that it's equal offset modulo shm_alignment and
507  * assumes it can't be in VAC conflict with any larger than PAGESIZE mapping.
508  */
509 int
510 map_addr_vacalign_check(caddr_t addr, u_offset_t off)
511 {
512 	if (vac) {
513 		return (((uintptr_t)addr ^ off) & shm_alignment - 1);
514 	} else {
515 		return (0);
516 	}
517 }
518 
519 /*
520  * Sanity control. Don't use large pages regardless of user
521  * settings if there's less than priv or shm_lpg_min_physmem memory installed.
522  * The units for this variable is 8K pages.
523  */
524 pgcnt_t shm_lpg_min_physmem = 131072;			/* 1GB */
525 pgcnt_t privm_lpg_min_physmem = 131072;			/* 1GB */
526 
527 static size_t
528 map_pgszheap(struct proc *p, caddr_t addr, size_t len)
529 {
530 	size_t		pgsz = MMU_PAGESIZE;
531 	int		szc;
532 
533 	/*
534 	 * If len is zero, retrieve from proc and don't demote the page size.
535 	 * Use atleast the default pagesize.
536 	 */
537 	if (len == 0) {
538 		len = p->p_brkbase + p->p_brksize - p->p_bssbase;
539 	}
540 	len = MAX(len, default_uheap_lpsize);
541 
542 	for (szc = mmu_page_sizes - 1; szc >= 0; szc--) {
543 		pgsz = hw_page_array[szc].hp_size;
544 		if ((disable_auto_data_large_pages & (1 << szc)) ||
545 		    pgsz > max_uheap_lpsize)
546 			continue;
547 		if (len >= pgsz) {
548 			break;
549 		}
550 	}
551 
552 	/*
553 	 * If addr == 0 we were called by memcntl() when the
554 	 * size code is 0.  Don't set pgsz less than current size.
555 	 */
556 	if (addr == 0 && (pgsz < hw_page_array[p->p_brkpageszc].hp_size)) {
557 		pgsz = hw_page_array[p->p_brkpageszc].hp_size;
558 	}
559 
560 	return (pgsz);
561 }
562 
563 static size_t
564 map_pgszstk(struct proc *p, caddr_t addr, size_t len)
565 {
566 	size_t		pgsz = MMU_PAGESIZE;
567 	int		szc;
568 
569 	/*
570 	 * If len is zero, retrieve from proc and don't demote the page size.
571 	 * Use atleast the default pagesize.
572 	 */
573 	if (len == 0) {
574 		len = p->p_stksize;
575 	}
576 	len = MAX(len, default_ustack_lpsize);
577 
578 	for (szc = mmu_page_sizes - 1; szc >= 0; szc--) {
579 		pgsz = hw_page_array[szc].hp_size;
580 		if ((disable_auto_data_large_pages & (1 << szc)) ||
581 		    pgsz > max_ustack_lpsize)
582 			continue;
583 		if (len >= pgsz) {
584 			break;
585 		}
586 	}
587 
588 	/*
589 	 * If addr == 0 we were called by memcntl() or exec_args() when the
590 	 * size code is 0.  Don't set pgsz less than current size.
591 	 */
592 	if (addr == 0 && (pgsz < hw_page_array[p->p_stkpageszc].hp_size)) {
593 		pgsz = hw_page_array[p->p_stkpageszc].hp_size;
594 	}
595 
596 	return (pgsz);
597 }
598 
599 static size_t
600 map_pgszism(caddr_t addr, size_t len)
601 {
602 	uint_t szc;
603 	size_t pgsz;
604 
605 	for (szc = mmu_page_sizes - 1; szc >= TTE4M; szc--) {
606 		if (disable_ism_large_pages & (1 << szc))
607 			continue;
608 
609 		pgsz = hw_page_array[szc].hp_size;
610 		if ((len >= pgsz) && IS_P2ALIGNED(addr, pgsz))
611 			return (pgsz);
612 	}
613 
614 	return (DEFAULT_ISM_PAGESIZE);
615 }
616 
617 /*
618  * Suggest a page size to be used to map a segment of type maptype and length
619  * len.  Returns a page size (not a size code).
620  */
621 /* ARGSUSED */
622 size_t
623 map_pgsz(int maptype, struct proc *p, caddr_t addr, size_t len, int memcntl)
624 {
625 	size_t	pgsz = MMU_PAGESIZE;
626 
627 	ASSERT(maptype != MAPPGSZ_VA);
628 
629 	if (maptype != MAPPGSZ_ISM && physmem < privm_lpg_min_physmem) {
630 		return (MMU_PAGESIZE);
631 	}
632 
633 	switch (maptype) {
634 	case MAPPGSZ_ISM:
635 		pgsz = map_pgszism(addr, len);
636 		break;
637 
638 	case MAPPGSZ_STK:
639 		if (max_ustack_lpsize > MMU_PAGESIZE) {
640 			pgsz = map_pgszstk(p, addr, len);
641 		}
642 		break;
643 
644 	case MAPPGSZ_HEAP:
645 		if (max_uheap_lpsize > MMU_PAGESIZE) {
646 			pgsz = map_pgszheap(p, addr, len);
647 		}
648 		break;
649 	}
650 	return (pgsz);
651 }
652 
653 
654 /* assumes TTE8K...TTE4M == szc */
655 
656 static uint_t
657 map_szcvec(caddr_t addr, size_t size, uintptr_t off, int disable_lpgs,
658     size_t max_lpsize, size_t min_physmem)
659 {
660 	caddr_t eaddr = addr + size;
661 	uint_t szcvec = 0;
662 	caddr_t raddr;
663 	caddr_t readdr;
664 	size_t pgsz;
665 	int i;
666 
667 	if (physmem < min_physmem || max_lpsize <= MMU_PAGESIZE) {
668 		return (0);
669 	}
670 	for (i = mmu_page_sizes - 1; i > 0; i--) {
671 		if (disable_lpgs & (1 << i)) {
672 			continue;
673 		}
674 		pgsz = page_get_pagesize(i);
675 		if (pgsz > max_lpsize) {
676 			continue;
677 		}
678 		raddr = (caddr_t)P2ROUNDUP((uintptr_t)addr, pgsz);
679 		readdr = (caddr_t)P2ALIGN((uintptr_t)eaddr, pgsz);
680 		if (raddr < addr || raddr >= readdr) {
681 			continue;
682 		}
683 		if (P2PHASE((uintptr_t)addr ^ off, pgsz)) {
684 			continue;
685 		}
686 		szcvec |= (1 << i);
687 		/*
688 		 * And or in the remaining enabled page sizes.
689 		 */
690 		szcvec |= P2PHASE(~disable_lpgs, (1 << i));
691 		szcvec &= ~1; /* no need to return 8K pagesize */
692 		break;
693 	}
694 	return (szcvec);
695 }
696 
697 /*
698  * Return a bit vector of large page size codes that
699  * can be used to map [addr, addr + len) region.
700  */
701 /* ARGSUSED */
702 uint_t
703 map_pgszcvec(caddr_t addr, size_t size, uintptr_t off, int flags, int type,
704     int memcntl)
705 {
706 	if (flags & MAP_TEXT) {
707 		return (map_szcvec(addr, size, off,
708 		    disable_auto_text_large_pages,
709 		    max_utext_lpsize, shm_lpg_min_physmem));
710 
711 	} else if (flags & MAP_INITDATA) {
712 		return (map_szcvec(addr, size, off,
713 		    disable_auto_data_large_pages,
714 		    max_uidata_lpsize, privm_lpg_min_physmem));
715 
716 	} else if (type == MAPPGSZC_SHM) {
717 		return (map_szcvec(addr, size, off,
718 		    disable_auto_data_large_pages,
719 		    max_shm_lpsize, shm_lpg_min_physmem));
720 
721 	} else if (type == MAPPGSZC_HEAP) {
722 		return (map_szcvec(addr, size, off,
723 		    disable_auto_data_large_pages,
724 		    max_uheap_lpsize, privm_lpg_min_physmem));
725 
726 	} else if (type == MAPPGSZC_STACK) {
727 		return (map_szcvec(addr, size, off,
728 		    disable_auto_data_large_pages,
729 		    max_ustack_lpsize, privm_lpg_min_physmem));
730 
731 	} else {
732 		return (map_szcvec(addr, size, off,
733 		    disable_auto_data_large_pages,
734 		    max_privmap_lpsize, privm_lpg_min_physmem));
735 	}
736 }
737 
738 /*
739  * Anchored in the table below are counters used to keep track
740  * of free contiguous physical memory. Each element of the table contains
741  * the array of counters, the size of array which is allocated during
742  * startup based on physmax and a shift value used to convert a pagenum
743  * into a counter array index or vice versa. The table has page size
744  * for rows and region size for columns:
745  *
746  *	page_counters[page_size][region_size]
747  *
748  *	page_size: 	TTE size code of pages on page_size freelist.
749  *
750  *	region_size:	TTE size code of a candidate larger page made up
751  *			made up of contiguous free page_size pages.
752  *
753  * As you go across a page_size row increasing region_size each
754  * element keeps track of how many (region_size - 1) size groups
755  * made up of page_size free pages can be coalesced into a
756  * regsion_size page. Yuck! Lets try an example:
757  *
758  * 	page_counters[1][3] is the table element used for identifying
759  *	candidate 4M pages from contiguous pages off the 64K free list.
760  *	Each index in the page_counters[1][3].array spans 4M. Its the
761  *	number of free 512K size (regsion_size - 1) groups of contiguous
762  *	64K free pages.	So when page_counters[1][3].counters[n] == 8
763  *	we know we have a candidate 4M page made up of 512K size groups
764  *	of 64K free pages.
765  */
766 
767 /*
768  * Per page size free lists. 3rd (max_mem_nodes) and 4th (page coloring bins)
769  * dimensions are allocated dynamically.
770  */
771 page_t ***page_freelists[MMU_PAGE_SIZES][MAX_MEM_TYPES];
772 
773 /*
774  * For now there is only a single size cache list.
775  * Allocated dynamically.
776  */
777 page_t ***page_cachelists[MAX_MEM_TYPES];
778 
779 kmutex_t *fpc_mutex[NPC_MUTEX];
780 kmutex_t *cpc_mutex[NPC_MUTEX];
781 
782 /*
783  * Calculate space needed for page freelists and counters
784  */
785 size_t
786 calc_free_pagelist_sz(void)
787 {
788 	int szc;
789 	size_t alloc_sz, cache_sz, free_sz;
790 
791 	/*
792 	 * one cachelist per color, node, and type
793 	 */
794 	cache_sz = (page_get_pagecolors(0) * sizeof (page_t *)) +
795 	    sizeof (page_t **);
796 	cache_sz *= max_mem_nodes * MAX_MEM_TYPES;
797 
798 	/*
799 	 * one freelist per size, color, node, and type
800 	 */
801 	free_sz = sizeof (page_t **);
802 	for (szc = 0; szc < mmu_page_sizes; szc++)
803 		free_sz += sizeof (page_t *) * page_get_pagecolors(szc);
804 	free_sz *= max_mem_nodes * MAX_MEM_TYPES;
805 
806 	alloc_sz = cache_sz + free_sz + page_ctrs_sz();
807 	return (alloc_sz);
808 }
809 
810 caddr_t
811 alloc_page_freelists(caddr_t alloc_base)
812 {
813 	int	mnode, mtype;
814 	int	szc, clrs;
815 
816 	/*
817 	 * We only support small pages in the cachelist.
818 	 */
819 	for (mtype = 0; mtype < MAX_MEM_TYPES; mtype++) {
820 		page_cachelists[mtype] = (page_t ***)alloc_base;
821 		alloc_base += (max_mem_nodes * sizeof (page_t **));
822 		for (mnode = 0; mnode < max_mem_nodes; mnode++) {
823 			page_cachelists[mtype][mnode] = (page_t **)alloc_base;
824 			alloc_base +=
825 			    (page_get_pagecolors(0) * sizeof (page_t *));
826 		}
827 	}
828 
829 	/*
830 	 * Allocate freelists bins for all
831 	 * supported page sizes.
832 	 */
833 	for (szc = 0; szc < mmu_page_sizes; szc++) {
834 		clrs = page_get_pagecolors(szc);
835 		for (mtype = 0; mtype < MAX_MEM_TYPES; mtype++) {
836 			page_freelists[szc][mtype] = (page_t ***)alloc_base;
837 			alloc_base += (max_mem_nodes * sizeof (page_t **));
838 			for (mnode = 0; mnode < max_mem_nodes; mnode++) {
839 				page_freelists[szc][mtype][mnode] =
840 				    (page_t **)alloc_base;
841 				alloc_base += (clrs * (sizeof (page_t *)));
842 			}
843 		}
844 	}
845 
846 	alloc_base = page_ctrs_alloc(alloc_base);
847 	return (alloc_base);
848 }
849 
850 /*
851  * Allocate page_freelists locks for a memnode from the nucleus data
852  * area. This is the first time that mmu_page_sizes is used during
853  * bootup, so check mmu_page_sizes initialization.
854  */
855 int
856 ndata_alloc_page_mutexs(struct memlist *ndata)
857 {
858 	size_t alloc_sz;
859 	caddr_t alloc_base;
860 	int	i;
861 	void	page_coloring_init();
862 
863 	page_coloring_init();
864 	if (&mmu_init_mmu_page_sizes) {
865 		if (!mmu_init_mmu_page_sizes(0)) {
866 			cmn_err(CE_PANIC, "mmu_page_sizes %d not initialized",
867 			    mmu_page_sizes);
868 		}
869 	}
870 	ASSERT(mmu_page_sizes >= DEFAULT_MMU_PAGE_SIZES);
871 
872 	/* fpc_mutex and cpc_mutex */
873 	alloc_sz = 2 * NPC_MUTEX * max_mem_nodes * sizeof (kmutex_t);
874 
875 	alloc_base = ndata_alloc(ndata, alloc_sz, ecache_alignsize);
876 	if (alloc_base == NULL)
877 		return (-1);
878 
879 	ASSERT(((uintptr_t)alloc_base & (ecache_alignsize - 1)) == 0);
880 
881 	for (i = 0; i < NPC_MUTEX; i++) {
882 		fpc_mutex[i] = (kmutex_t *)alloc_base;
883 		alloc_base += (sizeof (kmutex_t) * max_mem_nodes);
884 		cpc_mutex[i] = (kmutex_t *)alloc_base;
885 		alloc_base += (sizeof (kmutex_t) * max_mem_nodes);
886 	}
887 	return (0);
888 }
889 
890 /*
891  * To select our starting bin, we stride through the bins with a stride
892  * of 337.  Why 337?  It's prime, it's largeish, and it performs well both
893  * in simulation and practice for different workloads on varying cache sizes.
894  */
895 uint32_t color_start_current = 0;
896 uint32_t color_start_stride = 337;
897 int color_start_random = 0;
898 
899 /* ARGSUSED */
900 uint_t
901 get_color_start(struct as *as)
902 {
903 	uint32_t old, new;
904 
905 	if (consistent_coloring == 2 || color_start_random) {
906 		return ((uint_t)(((gettick()) << (vac_shift - MMU_PAGESHIFT)) &
907 		    (hw_page_array[0].hp_colors - 1)));
908 	}
909 
910 	do {
911 		old = color_start_current;
912 		new = old + (color_start_stride << (vac_shift - MMU_PAGESHIFT));
913 	} while (atomic_cas_32(&color_start_current, old, new) != old);
914 
915 	return ((uint_t)(new));
916 }
917 
918 /*
919  * Called once at startup from kphysm_init() -- before memialloc()
920  * is invoked to do the 1st page_free()/page_freelist_add().
921  *
922  * initializes page_colors and page_colors_mask based on ecache_setsize.
923  *
924  * Also initializes the counter locks.
925  */
926 void
927 page_coloring_init()
928 {
929 	int	a, i;
930 	uint_t colors;
931 
932 	if (do_pg_coloring == 0) {
933 		page_colors = 1;
934 		for (i = 0; i < mmu_page_sizes; i++) {
935 			colorequivszc[i] = 0;
936 			hw_page_array[i].hp_colors = 1;
937 		}
938 		return;
939 	}
940 
941 	/*
942 	 * Calculate page_colors from ecache_setsize. ecache_setsize contains
943 	 * the max ecache setsize of all cpus configured in the system or, for
944 	 * cheetah+ systems, the max possible ecache setsize for all possible
945 	 * cheetah+ cpus.
946 	 */
947 	page_colors = ecache_setsize / MMU_PAGESIZE;
948 	page_colors_mask = page_colors - 1;
949 
950 	vac_colors = vac_size / MMU_PAGESIZE;
951 	vac_colors_mask = vac_colors -1;
952 
953 	page_coloring_shift = 0;
954 	a = ecache_setsize;
955 	while (a >>= 1) {
956 		page_coloring_shift++;
957 	}
958 
959 	/* initialize number of colors per page size */
960 	for (i = 0; i < mmu_page_sizes; i++) {
961 		hw_page_array[i].hp_colors = (page_colors_mask >>
962 		    (hw_page_array[i].hp_shift - hw_page_array[0].hp_shift))
963 		    + 1;
964 		colorequivszc[i] = 0;
965 	}
966 
967 	/*
968 	 * initialize cpu_page_colors if ecache setsizes are homogenous.
969 	 * cpu_page_colors set to -1 during DR operation or during startup
970 	 * if setsizes are heterogenous.
971 	 *
972 	 * The value of cpu_page_colors determines if additional color bins
973 	 * need to be checked for a particular color in the page_get routines.
974 	 */
975 	if (cpu_setsize > 0 && cpu_page_colors == 0 &&
976 	    cpu_setsize < ecache_setsize) {
977 		cpu_page_colors = cpu_setsize / MMU_PAGESIZE;
978 		a = lowbit(page_colors) - lowbit(cpu_page_colors);
979 		ASSERT(a > 0);
980 		ASSERT(a < 16);
981 
982 		for (i = 0; i < mmu_page_sizes; i++) {
983 			if ((colors = hw_page_array[i].hp_colors) <= 1) {
984 				continue;
985 			}
986 			while ((colors >> a) == 0)
987 				a--;
988 			ASSERT(a >= 0);
989 
990 			/* higher 4 bits encodes color equiv mask */
991 			colorequivszc[i] = (a << 4);
992 		}
993 	}
994 
995 	/* do cpu specific color initialization */
996 	if (&page_coloring_init_cpu) {
997 		page_coloring_init_cpu();
998 	}
999 }
1000 
1001 int
1002 bp_color(struct buf *bp)
1003 {
1004 	int color = -1;
1005 
1006 	if (vac) {
1007 		if ((bp->b_flags & B_PAGEIO) != 0) {
1008 			color = sfmmu_get_ppvcolor(bp->b_pages);
1009 		} else if (bp->b_un.b_addr != NULL) {
1010 			color = sfmmu_get_addrvcolor(bp->b_un.b_addr);
1011 		}
1012 	}
1013 	return (color < 0 ? 0 : ptob(color));
1014 }
1015 
1016 /*
1017  * Function for flushing D-cache when performing module relocations
1018  * to an alternate mapping.  Stubbed out on all platforms except sun4u,
1019  * at least for now.
1020  */
1021 void
1022 dcache_flushall()
1023 {
1024 	sfmmu_cache_flushall();
1025 }
1026 
1027 static int
1028 kdi_range_overlap(uintptr_t va1, size_t sz1, uintptr_t va2, size_t sz2)
1029 {
1030 	if (va1 < va2 && va1 + sz1 <= va2)
1031 		return (0);
1032 
1033 	if (va2 < va1 && va2 + sz2 <= va1)
1034 		return (0);
1035 
1036 	return (1);
1037 }
1038 
1039 /*
1040  * Return the number of bytes, relative to the beginning of a given range, that
1041  * are non-toxic (can be read from and written to with relative impunity).
1042  */
1043 size_t
1044 kdi_range_is_nontoxic(uintptr_t va, size_t sz, int write)
1045 {
1046 	/* OBP reads are harmless, but we don't want people writing there */
1047 	if (write && kdi_range_overlap(va, sz, OFW_START_ADDR, OFW_END_ADDR -
1048 	    OFW_START_ADDR + 1))
1049 		return (va < OFW_START_ADDR ? OFW_START_ADDR - va : 0);
1050 
1051 	if (kdi_range_overlap(va, sz, PIOMAPBASE, PIOMAPSIZE))
1052 		return (va < PIOMAPBASE ? PIOMAPBASE - va : 0);
1053 
1054 	return (sz); /* no overlap */
1055 }
1056 
1057 /*
1058  * Minimum physmem required for enabling large pages for kernel heap
1059  * Currently we do not enable lp for kmem on systems with less
1060  * than 1GB of memory. This value can be changed via /etc/system
1061  */
1062 size_t segkmem_lpminphysmem = 0x40000000;	/* 1GB */
1063 
1064 /*
1065  * this function chooses large page size for kernel heap
1066  */
1067 size_t
1068 get_segkmem_lpsize(size_t lpsize)
1069 {
1070 	size_t memtotal = physmem * PAGESIZE;
1071 	size_t mmusz;
1072 	uint_t szc;
1073 
1074 	if (memtotal < segkmem_lpminphysmem)
1075 		return (PAGESIZE);
1076 
1077 	if (plat_lpkmem_is_supported != NULL &&
1078 	    plat_lpkmem_is_supported() == 0)
1079 		return (PAGESIZE);
1080 
1081 	mmusz = mmu_get_kernel_lpsize(lpsize);
1082 	szc = page_szc(mmusz);
1083 
1084 	while (szc) {
1085 		if (!(disable_large_pages & (1 << szc)))
1086 			return (page_get_pagesize(szc));
1087 		szc--;
1088 	}
1089 	return (PAGESIZE);
1090 }
1091