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 (c) 1998, 2010, Oracle and/or its affiliates. All rights reserved.
23 * Copyright 2016 Joyent, Inc.
24 */
25
26 #include <sys/types.h>
27 #include <sys/t_lock.h>
28 #include <sys/param.h>
29 #include <sys/sysmacros.h>
30 #include <sys/tuneable.h>
31 #include <sys/systm.h>
32 #include <sys/vm.h>
33 #include <sys/kmem.h>
34 #include <sys/vmem.h>
35 #include <sys/mman.h>
36 #include <sys/cmn_err.h>
37 #include <sys/debug.h>
38 #include <sys/dumphdr.h>
39 #include <sys/bootconf.h>
40 #include <sys/lgrp.h>
41 #include <vm/seg_kmem.h>
42 #include <vm/hat.h>
43 #include <vm/page.h>
44 #include <vm/vm_dep.h>
45 #include <vm/faultcode.h>
46 #include <sys/promif.h>
47 #include <vm/seg_kp.h>
48 #include <sys/bitmap.h>
49 #include <sys/mem_cage.h>
50
51 #ifdef __sparc
52 #include <sys/ivintr.h>
53 #include <sys/panic.h>
54 #endif
55
56 /*
57 * seg_kmem is the primary kernel memory segment driver. It
58 * maps the kernel heap [kernelheap, ekernelheap), module text,
59 * and all memory which was allocated before the VM was initialized
60 * into kas.
61 *
62 * Pages which belong to seg_kmem are hashed into &kvp vnode at
63 * an offset equal to (u_offset_t)virt_addr, and have p_lckcnt >= 1.
64 * They must never be paged out since segkmem_fault() is a no-op to
65 * prevent recursive faults.
66 *
67 * Currently, seg_kmem pages are sharelocked (p_sharelock == 1) on
68 * __x86 and are unlocked (p_sharelock == 0) on __sparc. Once __x86
69 * supports relocation the #ifdef kludges can be removed.
70 *
71 * seg_kmem pages may be subject to relocation by page_relocate(),
72 * provided that the HAT supports it; if this is so, segkmem_reloc
73 * will be set to a nonzero value. All boot time allocated memory as
74 * well as static memory is considered off limits to relocation.
75 * Pages are "relocatable" if p_state does not have P_NORELOC set, so
76 * we request P_NORELOC pages for memory that isn't safe to relocate.
77 *
78 * The kernel heap is logically divided up into four pieces:
79 *
80 * heap32_arena is for allocations that require 32-bit absolute
81 * virtual addresses (e.g. code that uses 32-bit pointers/offsets).
82 *
83 * heap_core is for allocations that require 2GB *relative*
84 * offsets; in other words all memory from heap_core is within
85 * 2GB of all other memory from the same arena. This is a requirement
86 * of the addressing modes of some processors in supervisor code.
87 *
88 * heap_arena is the general heap arena.
89 *
90 * static_arena is the static memory arena. Allocations from it
91 * are not subject to relocation so it is safe to use the memory
92 * physical address as well as the virtual address (e.g. the VA to
93 * PA translations are static). Caches may import from static_arena;
94 * all other static memory allocations should use static_alloc_arena.
95 *
96 * On some platforms which have limited virtual address space, seg_kmem
97 * may share [kernelheap, ekernelheap) with seg_kp; if this is so,
98 * segkp_bitmap is non-NULL, and each bit represents a page of virtual
99 * address space which is actually seg_kp mapped.
100 */
101
102 extern ulong_t *segkp_bitmap; /* Is set if segkp is from the kernel heap */
103
104 char *kernelheap; /* start of primary kernel heap */
105 char *ekernelheap; /* end of primary kernel heap */
106 struct seg kvseg; /* primary kernel heap segment */
107 struct seg kvseg_core; /* "core" kernel heap segment */
108 struct seg kzioseg; /* Segment for zio mappings */
109 vmem_t *heap_arena; /* primary kernel heap arena */
110 vmem_t *heap_core_arena; /* core kernel heap arena */
111 char *heap_core_base; /* start of core kernel heap arena */
112 char *heap_lp_base; /* start of kernel large page heap arena */
113 char *heap_lp_end; /* end of kernel large page heap arena */
114 vmem_t *hat_memload_arena; /* HAT translation data */
115 struct seg kvseg32; /* 32-bit kernel heap segment */
116 vmem_t *heap32_arena; /* 32-bit kernel heap arena */
117 vmem_t *heaptext_arena; /* heaptext arena */
118 struct as kas; /* kernel address space */
119 int segkmem_reloc; /* enable/disable relocatable segkmem pages */
120 vmem_t *static_arena; /* arena for caches to import static memory */
121 vmem_t *static_alloc_arena; /* arena for allocating static memory */
122 vmem_t *zio_arena = NULL; /* arena for allocating zio memory */
123 vmem_t *zio_alloc_arena = NULL; /* arena for allocating zio memory */
124
125 /*
126 * seg_kmem driver can map part of the kernel heap with large pages.
127 * Currently this functionality is implemented for sparc platforms only.
128 *
129 * The large page size "segkmem_lpsize" for kernel heap is selected in the
130 * platform specific code. It can also be modified via /etc/system file.
131 * Setting segkmem_lpsize to PAGESIZE in /etc/system disables usage of large
132 * pages for kernel heap. "segkmem_lpshift" is adjusted appropriately to
133 * match segkmem_lpsize.
134 *
135 * At boot time we carve from kernel heap arena a range of virtual addresses
136 * that will be used for large page mappings. This range [heap_lp_base,
137 * heap_lp_end) is set up as a separate vmem arena - "heap_lp_arena". We also
138 * create "kmem_lp_arena" that caches memory already backed up by large
139 * pages. kmem_lp_arena imports virtual segments from heap_lp_arena.
140 */
141
142 size_t segkmem_lpsize;
143 static uint_t segkmem_lpshift = PAGESHIFT;
144 int segkmem_lpszc = 0;
145
146 size_t segkmem_kmemlp_quantum = 0x400000; /* 4MB */
147 size_t segkmem_heaplp_quantum;
148 vmem_t *heap_lp_arena;
149 static vmem_t *kmem_lp_arena;
150 static vmem_t *segkmem_ppa_arena;
151 static segkmem_lpcb_t segkmem_lpcb;
152
153 /*
154 * We use "segkmem_kmemlp_max" to limit the total amount of physical memory
155 * consumed by the large page heap. By default this parameter is set to 1/8 of
156 * physmem but can be adjusted through /etc/system either directly or
157 * indirectly by setting "segkmem_kmemlp_pcnt" to the percent of physmem
158 * we allow for large page heap.
159 */
160 size_t segkmem_kmemlp_max;
161 static uint_t segkmem_kmemlp_pcnt;
162
163 /*
164 * Getting large pages for kernel heap could be problematic due to
165 * physical memory fragmentation. That's why we allow to preallocate
166 * "segkmem_kmemlp_min" bytes at boot time.
167 */
168 static size_t segkmem_kmemlp_min;
169
170 /*
171 * Throttling is used to avoid expensive tries to allocate large pages
172 * for kernel heap when a lot of succesive attempts to do so fail.
173 */
174 static ulong_t segkmem_lpthrottle_max = 0x400000;
175 static ulong_t segkmem_lpthrottle_start = 0x40;
176 static ulong_t segkmem_use_lpthrottle = 1;
177
178 /*
179 * Freed pages accumulate on a garbage list until segkmem is ready,
180 * at which point we call segkmem_gc() to free it all.
181 */
182 typedef struct segkmem_gc_list {
183 struct segkmem_gc_list *gc_next;
184 vmem_t *gc_arena;
185 size_t gc_size;
186 } segkmem_gc_list_t;
187
188 static segkmem_gc_list_t *segkmem_gc_list;
189
190 /*
191 * Allocations from the hat_memload arena add VM_MEMLOAD to their
192 * vmflags so that segkmem_xalloc() can inform the hat layer that it needs
193 * to take steps to prevent infinite recursion. HAT allocations also
194 * must be non-relocatable to prevent recursive page faults.
195 */
196 static void *
197 hat_memload_alloc(vmem_t *vmp, size_t size, int flags)
198 {
199 flags |= (VM_MEMLOAD | VM_NORELOC);
200 return (segkmem_alloc(vmp, size, flags));
201 }
202
203 /*
204 * Allocations from static_arena arena (or any other arena that uses
205 * segkmem_alloc_permanent()) require non-relocatable (permanently
206 * wired) memory pages, since these pages are referenced by physical
207 * as well as virtual address.
208 */
209 void *
210 segkmem_alloc_permanent(vmem_t *vmp, size_t size, int flags)
211 {
212 return (segkmem_alloc(vmp, size, flags | VM_NORELOC));
213 }
214
215 /*
216 * Initialize kernel heap boundaries.
217 */
218 void
219 kernelheap_init(
220 void *heap_start,
221 void *heap_end,
222 char *first_avail,
223 void *core_start,
224 void *core_end)
225 {
226 uintptr_t textbase;
227 size_t core_size;
228 size_t heap_size;
229 vmem_t *heaptext_parent;
230 size_t heap_lp_size = 0;
231 #ifdef __sparc
232 size_t kmem64_sz = kmem64_aligned_end - kmem64_base;
233 #endif /* __sparc */
234
235 kernelheap = heap_start;
236 ekernelheap = heap_end;
237
238 #ifdef __sparc
239 heap_lp_size = (((uintptr_t)heap_end - (uintptr_t)heap_start) / 4);
240 /*
241 * Bias heap_lp start address by kmem64_sz to reduce collisions
242 * in 4M kernel TSB between kmem64 area and heap_lp
243 */
244 kmem64_sz = P2ROUNDUP(kmem64_sz, MMU_PAGESIZE256M);
245 if (kmem64_sz <= heap_lp_size / 2)
246 heap_lp_size -= kmem64_sz;
247 heap_lp_base = ekernelheap - heap_lp_size;
248 heap_lp_end = heap_lp_base + heap_lp_size;
249 #endif /* __sparc */
250
251 /*
252 * If this platform has a 'core' heap area, then the space for
253 * overflow module text should be carved out of the end of that
254 * heap. Otherwise, it gets carved out of the general purpose
255 * heap.
256 */
257 core_size = (uintptr_t)core_end - (uintptr_t)core_start;
258 if (core_size > 0) {
259 ASSERT(core_size >= HEAPTEXT_SIZE);
260 textbase = (uintptr_t)core_end - HEAPTEXT_SIZE;
261 core_size -= HEAPTEXT_SIZE;
262 }
263 #ifndef __sparc
264 else {
265 ekernelheap -= HEAPTEXT_SIZE;
266 textbase = (uintptr_t)ekernelheap;
267 }
268 #endif
269
270 heap_size = (uintptr_t)ekernelheap - (uintptr_t)kernelheap;
271 heap_arena = vmem_init("heap", kernelheap, heap_size, PAGESIZE,
272 segkmem_alloc, segkmem_free);
273
274 if (core_size > 0) {
275 heap_core_arena = vmem_create("heap_core", core_start,
276 core_size, PAGESIZE, NULL, NULL, NULL, 0, VM_SLEEP);
277 heap_core_base = core_start;
278 } else {
279 heap_core_arena = heap_arena;
280 heap_core_base = kernelheap;
281 }
282
283 /*
284 * reserve space for the large page heap. If large pages for kernel
285 * heap is enabled large page heap arean will be created later in the
286 * boot sequence in segkmem_heap_lp_init(). Otherwise the allocated
287 * range will be returned back to the heap_arena.
288 */
289 if (heap_lp_size) {
290 (void) vmem_xalloc(heap_arena, heap_lp_size, PAGESIZE, 0, 0,
291 heap_lp_base, heap_lp_end,
292 VM_NOSLEEP | VM_BESTFIT | VM_PANIC);
293 }
294
295 /*
296 * Remove the already-spoken-for memory range [kernelheap, first_avail).
297 */
298 (void) vmem_xalloc(heap_arena, first_avail - kernelheap, PAGESIZE,
299 0, 0, kernelheap, first_avail, VM_NOSLEEP | VM_BESTFIT | VM_PANIC);
300
301 #ifdef __sparc
302 heap32_arena = vmem_create("heap32", (void *)SYSBASE32,
303 SYSLIMIT32 - SYSBASE32 - HEAPTEXT_SIZE, PAGESIZE, NULL,
304 NULL, NULL, 0, VM_SLEEP);
305 /*
306 * Prom claims the physical and virtual resources used by panicbuf
307 * and inter_vec_table. So reserve space for panicbuf, intr_vec_table,
308 * reserved interrupt vector data structures from 32-bit heap.
309 */
310 (void) vmem_xalloc(heap32_arena, PANICBUFSIZE, PAGESIZE, 0, 0,
311 panicbuf, panicbuf + PANICBUFSIZE,
312 VM_NOSLEEP | VM_BESTFIT | VM_PANIC);
313
314 (void) vmem_xalloc(heap32_arena, IVSIZE, PAGESIZE, 0, 0,
315 intr_vec_table, (caddr_t)intr_vec_table + IVSIZE,
316 VM_NOSLEEP | VM_BESTFIT | VM_PANIC);
317
318 textbase = SYSLIMIT32 - HEAPTEXT_SIZE;
319 heaptext_parent = NULL;
320 #else /* __sparc */
321 heap32_arena = heap_core_arena;
322 heaptext_parent = heap_core_arena;
323 #endif /* __sparc */
324
325 heaptext_arena = vmem_create("heaptext", (void *)textbase,
326 HEAPTEXT_SIZE, PAGESIZE, NULL, NULL, heaptext_parent, 0, VM_SLEEP);
327
328 /*
329 * Create a set of arenas for memory with static translations
330 * (e.g. VA -> PA translations cannot change). Since using
331 * kernel pages by physical address implies it isn't safe to
332 * walk across page boundaries, the static_arena quantum must
333 * be PAGESIZE. Any kmem caches that require static memory
334 * should source from static_arena, while direct allocations
335 * should only use static_alloc_arena.
336 */
337 static_arena = vmem_create("static", NULL, 0, PAGESIZE,
338 segkmem_alloc_permanent, segkmem_free, heap_arena, 0, VM_SLEEP);
339 static_alloc_arena = vmem_create("static_alloc", NULL, 0,
340 sizeof (uint64_t), vmem_alloc, vmem_free, static_arena,
341 0, VM_SLEEP);
342
343 /*
344 * Create an arena for translation data (ptes, hmes, or hblks).
345 * We need an arena for this because hat_memload() is essential
346 * to vmem_populate() (see comments in common/os/vmem.c).
347 *
348 * Note: any kmem cache that allocates from hat_memload_arena
349 * must be created as a KMC_NOHASH cache (i.e. no external slab
350 * and bufctl structures to allocate) so that slab creation doesn't
351 * require anything more than a single vmem_alloc().
352 */
353 hat_memload_arena = vmem_create("hat_memload", NULL, 0, PAGESIZE,
354 hat_memload_alloc, segkmem_free, heap_arena, 0,
355 VM_SLEEP | VMC_POPULATOR | VMC_DUMPSAFE);
356 }
357
358 void
359 boot_mapin(caddr_t addr, size_t size)
360 {
361 caddr_t eaddr;
362 page_t *pp;
363 pfn_t pfnum;
364
365 if (page_resv(btop(size), KM_NOSLEEP) == 0)
366 panic("boot_mapin: page_resv failed");
367
368 for (eaddr = addr + size; addr < eaddr; addr += PAGESIZE) {
369 pfnum = va_to_pfn(addr);
370 if (pfnum == PFN_INVALID)
371 continue;
372 if ((pp = page_numtopp_nolock(pfnum)) == NULL)
373 panic("boot_mapin(): No pp for pfnum = %lx", pfnum);
374
375 /*
376 * must break up any large pages that may have constituent
377 * pages being utilized for BOP_ALLOC()'s before calling
378 * page_numtopp().The locking code (ie. page_reclaim())
379 * can't handle them
380 */
381 if (pp->p_szc != 0)
382 page_boot_demote(pp);
383
384 pp = page_numtopp(pfnum, SE_EXCL);
385 if (pp == NULL || PP_ISFREE(pp))
386 panic("boot_alloc: pp is NULL or free");
387
388 /*
389 * If the cage is on but doesn't yet contain this page,
390 * mark it as non-relocatable.
391 */
392 if (kcage_on && !PP_ISNORELOC(pp)) {
393 PP_SETNORELOC(pp);
394 PLCNT_XFER_NORELOC(pp);
395 }
396
397 (void) page_hashin(pp, &kvp, (u_offset_t)(uintptr_t)addr, NULL);
398 pp->p_lckcnt = 1;
399 #if defined(__x86)
400 page_downgrade(pp);
401 #else
402 page_unlock(pp);
403 #endif
404 }
405 }
406
407 /*
408 * Get pages from boot and hash them into the kernel's vp.
409 * Used after page structs have been allocated, but before segkmem is ready.
410 */
411 void *
412 boot_alloc(void *inaddr, size_t size, uint_t align)
413 {
414 caddr_t addr = inaddr;
415
416 if (bootops == NULL)
417 prom_panic("boot_alloc: attempt to allocate memory after "
418 "BOP_GONE");
419
420 size = ptob(btopr(size));
421 #ifdef __sparc
422 if (bop_alloc_chunk(addr, size, align) != (caddr_t)addr)
423 panic("boot_alloc: bop_alloc_chunk failed");
424 #else
425 if (BOP_ALLOC(bootops, addr, size, align) != addr)
426 panic("boot_alloc: BOP_ALLOC failed");
427 #endif
428 boot_mapin((caddr_t)addr, size);
429 return (addr);
430 }
431
432 static void
433 segkmem_badop()
434 {
435 panic("segkmem_badop");
436 }
437
438 #define SEGKMEM_BADOP(t) (t(*)())(uintptr_t)segkmem_badop
439
440 /*ARGSUSED*/
441 static faultcode_t
442 segkmem_fault(struct hat *hat, struct seg *seg, caddr_t addr, size_t size,
443 enum fault_type type, enum seg_rw rw)
444 {
445 pgcnt_t npages;
446 spgcnt_t pg;
447 page_t *pp;
448 struct vnode *vp = seg->s_data;
449
450 ASSERT(RW_READ_HELD(&seg->s_as->a_lock));
451
452 if (seg->s_as != &kas || size > seg->s_size ||
453 addr < seg->s_base || addr + size > seg->s_base + seg->s_size)
454 panic("segkmem_fault: bad args");
455
456 /*
457 * If it is one of segkp pages, call segkp_fault.
458 */
459 if (segkp_bitmap && seg == &kvseg &&
460 BT_TEST(segkp_bitmap, btop((uintptr_t)(addr - seg->s_base))))
461 return (SEGOP_FAULT(hat, segkp, addr, size, type, rw));
462
463 if (rw != S_READ && rw != S_WRITE && rw != S_OTHER)
464 return (FC_NOSUPPORT);
465
466 npages = btopr(size);
467
468 switch (type) {
469 case F_SOFTLOCK: /* lock down already-loaded translations */
470 for (pg = 0; pg < npages; pg++) {
471 pp = page_lookup(vp, (u_offset_t)(uintptr_t)addr,
472 SE_SHARED);
473 if (pp == NULL) {
474 /*
475 * Hmm, no page. Does a kernel mapping
476 * exist for it?
477 */
478 if (!hat_probe(kas.a_hat, addr)) {
479 addr -= PAGESIZE;
480 while (--pg >= 0) {
481 pp = page_find(vp, (u_offset_t)
482 (uintptr_t)addr);
483 if (pp)
484 page_unlock(pp);
485 addr -= PAGESIZE;
486 }
487 return (FC_NOMAP);
488 }
489 }
490 addr += PAGESIZE;
491 }
492 if (rw == S_OTHER)
493 hat_reserve(seg->s_as, addr, size);
494 return (0);
495 case F_SOFTUNLOCK:
496 while (npages--) {
497 pp = page_find(vp, (u_offset_t)(uintptr_t)addr);
498 if (pp)
499 page_unlock(pp);
500 addr += PAGESIZE;
501 }
502 return (0);
503 default:
504 return (FC_NOSUPPORT);
505 }
506 /*NOTREACHED*/
507 }
508
509 static int
510 segkmem_setprot(struct seg *seg, caddr_t addr, size_t size, uint_t prot)
511 {
512 ASSERT(RW_LOCK_HELD(&seg->s_as->a_lock));
513
514 if (seg->s_as != &kas || size > seg->s_size ||
515 addr < seg->s_base || addr + size > seg->s_base + seg->s_size)
516 panic("segkmem_setprot: bad args");
517
518 /*
519 * If it is one of segkp pages, call segkp.
520 */
521 if (segkp_bitmap && seg == &kvseg &&
522 BT_TEST(segkp_bitmap, btop((uintptr_t)(addr - seg->s_base))))
523 return (SEGOP_SETPROT(segkp, addr, size, prot));
524
525 if (prot == 0)
526 hat_unload(kas.a_hat, addr, size, HAT_UNLOAD);
527 else
528 hat_chgprot(kas.a_hat, addr, size, prot);
529 return (0);
530 }
531
532 /*
533 * This is a dummy segkmem function overloaded to call segkp
534 * when segkp is under the heap.
535 */
536 /* ARGSUSED */
537 static int
538 segkmem_checkprot(struct seg *seg, caddr_t addr, size_t size, uint_t prot)
539 {
540 ASSERT(RW_LOCK_HELD(&seg->s_as->a_lock));
541
542 if (seg->s_as != &kas)
543 segkmem_badop();
544
545 /*
546 * If it is one of segkp pages, call into segkp.
547 */
548 if (segkp_bitmap && seg == &kvseg &&
549 BT_TEST(segkp_bitmap, btop((uintptr_t)(addr - seg->s_base))))
550 return (SEGOP_CHECKPROT(segkp, addr, size, prot));
551
552 segkmem_badop();
553 return (0);
554 }
555
556 /*
557 * This is a dummy segkmem function overloaded to call segkp
558 * when segkp is under the heap.
559 */
560 /* ARGSUSED */
561 static int
562 segkmem_kluster(struct seg *seg, caddr_t addr, ssize_t delta)
563 {
564 ASSERT(RW_LOCK_HELD(&seg->s_as->a_lock));
565
566 if (seg->s_as != &kas)
567 segkmem_badop();
568
569 /*
570 * If it is one of segkp pages, call into segkp.
571 */
572 if (segkp_bitmap && seg == &kvseg &&
573 BT_TEST(segkp_bitmap, btop((uintptr_t)(addr - seg->s_base))))
574 return (SEGOP_KLUSTER(segkp, addr, delta));
575
576 segkmem_badop();
577 return (0);
578 }
579
580 static void
581 segkmem_xdump_range(void *arg, void *start, size_t size)
582 {
583 struct as *as = arg;
584 caddr_t addr = start;
585 caddr_t addr_end = addr + size;
586
587 while (addr < addr_end) {
588 pfn_t pfn = hat_getpfnum(kas.a_hat, addr);
589 if (pfn != PFN_INVALID && pfn <= physmax && pf_is_memory(pfn))
590 dump_addpage(as, addr, pfn);
591 addr += PAGESIZE;
592 dump_timeleft = dump_timeout;
593 }
594 }
595
596 static void
597 segkmem_dump_range(void *arg, void *start, size_t size)
598 {
599 caddr_t addr = start;
600 caddr_t addr_end = addr + size;
601
602 /*
603 * If we are about to start dumping the range of addresses we
604 * carved out of the kernel heap for the large page heap walk
605 * heap_lp_arena to find what segments are actually populated
606 */
607 if (SEGKMEM_USE_LARGEPAGES &&
608 addr == heap_lp_base && addr_end == heap_lp_end &&
609 vmem_size(heap_lp_arena, VMEM_ALLOC) < size) {
610 vmem_walk(heap_lp_arena, VMEM_ALLOC | VMEM_REENTRANT,
611 segkmem_xdump_range, arg);
612 } else {
613 segkmem_xdump_range(arg, start, size);
614 }
615 }
616
617 static void
618 segkmem_dump(struct seg *seg)
619 {
620 /*
621 * The kernel's heap_arena (represented by kvseg) is a very large
622 * VA space, most of which is typically unused. To speed up dumping
623 * we use vmem_walk() to quickly find the pieces of heap_arena that
624 * are actually in use. We do the same for heap32_arena and
625 * heap_core.
626 *
627 * We specify VMEM_REENTRANT to vmem_walk() because dump_addpage()
628 * may ultimately need to allocate memory. Reentrant walks are
629 * necessarily imperfect snapshots. The kernel heap continues
630 * to change during a live crash dump, for example. For a normal
631 * crash dump, however, we know that there won't be any other threads
632 * messing with the heap. Therefore, at worst, we may fail to dump
633 * the pages that get allocated by the act of dumping; but we will
634 * always dump every page that was allocated when the walk began.
635 *
636 * The other segkmem segments are dense (fully populated), so there's
637 * no need to use this technique when dumping them.
638 *
639 * Note: when adding special dump handling for any new sparsely-
640 * populated segments, be sure to add similar handling to the ::kgrep
641 * code in mdb.
642 */
643 if (seg == &kvseg) {
644 vmem_walk(heap_arena, VMEM_ALLOC | VMEM_REENTRANT,
645 segkmem_dump_range, seg->s_as);
646 #ifndef __sparc
647 vmem_walk(heaptext_arena, VMEM_ALLOC | VMEM_REENTRANT,
648 segkmem_dump_range, seg->s_as);
649 #endif
650 } else if (seg == &kvseg_core) {
651 vmem_walk(heap_core_arena, VMEM_ALLOC | VMEM_REENTRANT,
652 segkmem_dump_range, seg->s_as);
653 } else if (seg == &kvseg32) {
654 vmem_walk(heap32_arena, VMEM_ALLOC | VMEM_REENTRANT,
655 segkmem_dump_range, seg->s_as);
656 vmem_walk(heaptext_arena, VMEM_ALLOC | VMEM_REENTRANT,
657 segkmem_dump_range, seg->s_as);
658 } else if (seg == &kzioseg) {
659 /*
660 * We don't want to dump pages attached to kzioseg since they
661 * contain file data from ZFS. If this page's segment is
662 * kzioseg return instead of writing it to the dump device.
663 */
664 return;
665 } else {
666 segkmem_dump_range(seg->s_as, seg->s_base, seg->s_size);
667 }
668 }
669
670 /*
671 * lock/unlock kmem pages over a given range [addr, addr+len).
672 * Returns a shadow list of pages in ppp. If there are holes
673 * in the range (e.g. some of the kernel mappings do not have
674 * underlying page_ts) returns ENOTSUP so that as_pagelock()
675 * will handle the range via as_fault(F_SOFTLOCK).
676 */
677 /*ARGSUSED*/
678 static int
679 segkmem_pagelock(struct seg *seg, caddr_t addr, size_t len,
680 page_t ***ppp, enum lock_type type, enum seg_rw rw)
681 {
682 page_t **pplist, *pp;
683 pgcnt_t npages;
684 spgcnt_t pg;
685 size_t nb;
686 struct vnode *vp = seg->s_data;
687
688 ASSERT(ppp != NULL);
689
690 /*
691 * If it is one of segkp pages, call into segkp.
692 */
693 if (segkp_bitmap && seg == &kvseg &&
694 BT_TEST(segkp_bitmap, btop((uintptr_t)(addr - seg->s_base))))
695 return (SEGOP_PAGELOCK(segkp, addr, len, ppp, type, rw));
696
697 npages = btopr(len);
698 nb = sizeof (page_t *) * npages;
699
700 if (type == L_PAGEUNLOCK) {
701 pplist = *ppp;
702 ASSERT(pplist != NULL);
703
704 for (pg = 0; pg < npages; pg++) {
705 pp = pplist[pg];
706 page_unlock(pp);
707 }
708 kmem_free(pplist, nb);
709 return (0);
710 }
711
712 ASSERT(type == L_PAGELOCK);
713
714 pplist = kmem_alloc(nb, KM_NOSLEEP);
715 if (pplist == NULL) {
716 *ppp = NULL;
717 return (ENOTSUP); /* take the slow path */
718 }
719
720 for (pg = 0; pg < npages; pg++) {
721 pp = page_lookup(vp, (u_offset_t)(uintptr_t)addr, SE_SHARED);
722 if (pp == NULL) {
723 while (--pg >= 0)
724 page_unlock(pplist[pg]);
725 kmem_free(pplist, nb);
726 *ppp = NULL;
727 return (ENOTSUP);
728 }
729 pplist[pg] = pp;
730 addr += PAGESIZE;
731 }
732
733 *ppp = pplist;
734 return (0);
735 }
736
737 /*
738 * This is a dummy segkmem function overloaded to call segkp
739 * when segkp is under the heap.
740 */
741 /* ARGSUSED */
742 static int
743 segkmem_getmemid(struct seg *seg, caddr_t addr, memid_t *memidp)
744 {
745 ASSERT(RW_LOCK_HELD(&seg->s_as->a_lock));
746
747 if (seg->s_as != &kas)
748 segkmem_badop();
749
750 /*
751 * If it is one of segkp pages, call into segkp.
752 */
753 if (segkp_bitmap && seg == &kvseg &&
754 BT_TEST(segkp_bitmap, btop((uintptr_t)(addr - seg->s_base))))
755 return (SEGOP_GETMEMID(segkp, addr, memidp));
756
757 segkmem_badop();
758 return (0);
759 }
760
761 /*ARGSUSED*/
762 static lgrp_mem_policy_info_t *
763 segkmem_getpolicy(struct seg *seg, caddr_t addr)
764 {
765 return (NULL);
766 }
767
768 /*ARGSUSED*/
769 static int
770 segkmem_capable(struct seg *seg, segcapability_t capability)
771 {
772 if (capability == S_CAPABILITY_NOMINFLT)
773 return (1);
774 return (0);
775 }
776
777 struct seg_ops segkmem_ops = {
778 SEGKMEM_BADOP(int), /* dup */
779 SEGKMEM_BADOP(int), /* unmap */
780 SEGKMEM_BADOP(void), /* free */
781 segkmem_fault,
782 SEGKMEM_BADOP(faultcode_t), /* faulta */
783 segkmem_setprot,
784 segkmem_checkprot,
785 segkmem_kluster,
786 SEGKMEM_BADOP(size_t), /* swapout */
787 SEGKMEM_BADOP(int), /* sync */
788 SEGKMEM_BADOP(size_t), /* incore */
789 SEGKMEM_BADOP(int), /* lockop */
790 SEGKMEM_BADOP(int), /* getprot */
791 SEGKMEM_BADOP(u_offset_t), /* getoffset */
792 SEGKMEM_BADOP(int), /* gettype */
793 SEGKMEM_BADOP(int), /* getvp */
794 SEGKMEM_BADOP(int), /* advise */
795 segkmem_dump,
796 segkmem_pagelock,
797 SEGKMEM_BADOP(int), /* setpgsz */
798 segkmem_getmemid,
799 segkmem_getpolicy, /* getpolicy */
800 segkmem_capable, /* capable */
801 seg_inherit_notsup /* inherit */
802 };
803
804 int
805 segkmem_zio_create(struct seg *seg)
806 {
807 ASSERT(seg->s_as == &kas && RW_WRITE_HELD(&kas.a_lock));
808 seg->s_ops = &segkmem_ops;
809 seg->s_data = &zvp;
810 kas.a_size += seg->s_size;
811 return (0);
812 }
813
814 int
815 segkmem_create(struct seg *seg)
816 {
817 ASSERT(seg->s_as == &kas && RW_WRITE_HELD(&kas.a_lock));
818 seg->s_ops = &segkmem_ops;
819 seg->s_data = &kvp;
820 kas.a_size += seg->s_size;
821 return (0);
822 }
823
824 /*ARGSUSED*/
825 page_t *
826 segkmem_page_create(void *addr, size_t size, int vmflag, void *arg)
827 {
828 struct seg kseg;
829 int pgflags;
830 struct vnode *vp = arg;
831
832 if (vp == NULL)
833 vp = &kvp;
834
835 kseg.s_as = &kas;
836 pgflags = PG_EXCL;
837
838 if (segkmem_reloc == 0 || (vmflag & VM_NORELOC))
839 pgflags |= PG_NORELOC;
840 if ((vmflag & VM_NOSLEEP) == 0)
841 pgflags |= PG_WAIT;
842 if (vmflag & VM_PANIC)
843 pgflags |= PG_PANIC;
844 if (vmflag & VM_PUSHPAGE)
845 pgflags |= PG_PUSHPAGE;
846 if (vmflag & VM_NORMALPRI) {
847 ASSERT(vmflag & VM_NOSLEEP);
848 pgflags |= PG_NORMALPRI;
849 }
850
851 return (page_create_va(vp, (u_offset_t)(uintptr_t)addr, size,
852 pgflags, &kseg, addr));
853 }
854
855 /*
856 * Allocate pages to back the virtual address range [addr, addr + size).
857 * If addr is NULL, allocate the virtual address space as well.
858 */
859 void *
860 segkmem_xalloc(vmem_t *vmp, void *inaddr, size_t size, int vmflag, uint_t attr,
861 page_t *(*page_create_func)(void *, size_t, int, void *), void *pcarg)
862 {
863 page_t *ppl;
864 caddr_t addr = inaddr;
865 pgcnt_t npages = btopr(size);
866 int allocflag;
867
868 if (inaddr == NULL && (addr = vmem_alloc(vmp, size, vmflag)) == NULL)
869 return (NULL);
870
871 ASSERT(((uintptr_t)addr & PAGEOFFSET) == 0);
872
873 if (page_resv(npages, vmflag & VM_KMFLAGS) == 0) {
874 if (inaddr == NULL)
875 vmem_free(vmp, addr, size);
876 return (NULL);
877 }
878
879 ppl = page_create_func(addr, size, vmflag, pcarg);
880 if (ppl == NULL) {
881 if (inaddr == NULL)
882 vmem_free(vmp, addr, size);
883 page_unresv(npages);
884 return (NULL);
885 }
886
887 /*
888 * Under certain conditions, we need to let the HAT layer know
889 * that it cannot safely allocate memory. Allocations from
890 * the hat_memload vmem arena always need this, to prevent
891 * infinite recursion.
892 *
893 * In addition, the x86 hat cannot safely do memory
894 * allocations while in vmem_populate(), because there
895 * is no simple bound on its usage.
896 */
897 if (vmflag & VM_MEMLOAD)
898 allocflag = HAT_NO_KALLOC;
899 #if defined(__x86)
900 else if (vmem_is_populator())
901 allocflag = HAT_NO_KALLOC;
902 #endif
903 else
904 allocflag = 0;
905
906 while (ppl != NULL) {
907 page_t *pp = ppl;
908 page_sub(&ppl, pp);
909 ASSERT(page_iolock_assert(pp));
910 ASSERT(PAGE_EXCL(pp));
911 page_io_unlock(pp);
912 hat_memload(kas.a_hat, (caddr_t)(uintptr_t)pp->p_offset, pp,
913 (PROT_ALL & ~PROT_USER) | HAT_NOSYNC | attr,
914 HAT_LOAD_LOCK | allocflag);
915 pp->p_lckcnt = 1;
916 #if defined(__x86)
917 page_downgrade(pp);
918 #else
919 if (vmflag & SEGKMEM_SHARELOCKED)
920 page_downgrade(pp);
921 else
922 page_unlock(pp);
923 #endif
924 }
925
926 return (addr);
927 }
928
929 static void *
930 segkmem_alloc_vn(vmem_t *vmp, size_t size, int vmflag, struct vnode *vp)
931 {
932 void *addr;
933 segkmem_gc_list_t *gcp, **prev_gcpp;
934
935 ASSERT(vp != NULL);
936
937 if (kvseg.s_base == NULL) {
938 #ifndef __sparc
939 if (bootops->bsys_alloc == NULL)
940 halt("Memory allocation between bop_alloc() and "
941 "kmem_alloc().\n");
942 #endif
943
944 /*
945 * There's not a lot of memory to go around during boot,
946 * so recycle it if we can.
947 */
948 for (prev_gcpp = &segkmem_gc_list; (gcp = *prev_gcpp) != NULL;
949 prev_gcpp = &gcp->gc_next) {
950 if (gcp->gc_arena == vmp && gcp->gc_size == size) {
951 *prev_gcpp = gcp->gc_next;
952 return (gcp);
953 }
954 }
955
956 addr = vmem_alloc(vmp, size, vmflag | VM_PANIC);
957 if (boot_alloc(addr, size, BO_NO_ALIGN) != addr)
958 panic("segkmem_alloc: boot_alloc failed");
959 return (addr);
960 }
961 return (segkmem_xalloc(vmp, NULL, size, vmflag, 0,
962 segkmem_page_create, vp));
963 }
964
965 void *
966 segkmem_alloc(vmem_t *vmp, size_t size, int vmflag)
967 {
968 return (segkmem_alloc_vn(vmp, size, vmflag, &kvp));
969 }
970
971 void *
972 segkmem_zio_alloc(vmem_t *vmp, size_t size, int vmflag)
973 {
974 return (segkmem_alloc_vn(vmp, size, vmflag, &zvp));
975 }
976
977 /*
978 * Any changes to this routine must also be carried over to
979 * devmap_free_pages() in the seg_dev driver. This is because
980 * we currently don't have a special kernel segment for non-paged
981 * kernel memory that is exported by drivers to user space.
982 */
983 static void
984 segkmem_free_vn(vmem_t *vmp, void *inaddr, size_t size, struct vnode *vp,
985 void (*func)(page_t *))
986 {
987 page_t *pp;
988 caddr_t addr = inaddr;
989 caddr_t eaddr;
990 pgcnt_t npages = btopr(size);
991
992 ASSERT(((uintptr_t)addr & PAGEOFFSET) == 0);
993 ASSERT(vp != NULL);
994
995 if (kvseg.s_base == NULL) {
996 segkmem_gc_list_t *gc = inaddr;
997 gc->gc_arena = vmp;
998 gc->gc_size = size;
999 gc->gc_next = segkmem_gc_list;
1000 segkmem_gc_list = gc;
1001 return;
1002 }
1003
1004 hat_unload(kas.a_hat, addr, size, HAT_UNLOAD_UNLOCK);
1005
1006 for (eaddr = addr + size; addr < eaddr; addr += PAGESIZE) {
1007 #if defined(__x86)
1008 pp = page_find(vp, (u_offset_t)(uintptr_t)addr);
1009 if (pp == NULL)
1010 panic("segkmem_free: page not found");
1011 if (!page_tryupgrade(pp)) {
1012 /*
1013 * Some other thread has a sharelock. Wait for
1014 * it to drop the lock so we can free this page.
1015 */
1016 page_unlock(pp);
1017 pp = page_lookup(vp, (u_offset_t)(uintptr_t)addr,
1018 SE_EXCL);
1019 }
1020 #else
1021 pp = page_lookup(vp, (u_offset_t)(uintptr_t)addr, SE_EXCL);
1022 #endif
1023 if (pp == NULL)
1024 panic("segkmem_free: page not found");
1025 /* Clear p_lckcnt so page_destroy() doesn't update availrmem */
1026 pp->p_lckcnt = 0;
1027 if (func)
1028 func(pp);
1029 else
1030 page_destroy(pp, 0);
1031 }
1032 if (func == NULL)
1033 page_unresv(npages);
1034
1035 if (vmp != NULL)
1036 vmem_free(vmp, inaddr, size);
1037
1038 }
1039
1040 void
1041 segkmem_xfree(vmem_t *vmp, void *inaddr, size_t size, void (*func)(page_t *))
1042 {
1043 segkmem_free_vn(vmp, inaddr, size, &kvp, func);
1044 }
1045
1046 void
1047 segkmem_free(vmem_t *vmp, void *inaddr, size_t size)
1048 {
1049 segkmem_free_vn(vmp, inaddr, size, &kvp, NULL);
1050 }
1051
1052 void
1053 segkmem_zio_free(vmem_t *vmp, void *inaddr, size_t size)
1054 {
1055 segkmem_free_vn(vmp, inaddr, size, &zvp, NULL);
1056 }
1057
1058 void
1059 segkmem_gc(void)
1060 {
1061 ASSERT(kvseg.s_base != NULL);
1062 while (segkmem_gc_list != NULL) {
1063 segkmem_gc_list_t *gc = segkmem_gc_list;
1064 segkmem_gc_list = gc->gc_next;
1065 segkmem_free(gc->gc_arena, gc, gc->gc_size);
1066 }
1067 }
1068
1069 /*
1070 * Legacy entry points from here to end of file.
1071 */
1072 void
1073 segkmem_mapin(struct seg *seg, void *addr, size_t size, uint_t vprot,
1074 pfn_t pfn, uint_t flags)
1075 {
1076 hat_unload(seg->s_as->a_hat, addr, size, HAT_UNLOAD_UNLOCK);
1077 hat_devload(seg->s_as->a_hat, addr, size, pfn, vprot,
1078 flags | HAT_LOAD_LOCK);
1079 }
1080
1081 void
1082 segkmem_mapout(struct seg *seg, void *addr, size_t size)
1083 {
1084 hat_unload(seg->s_as->a_hat, addr, size, HAT_UNLOAD_UNLOCK);
1085 }
1086
1087 void *
1088 kmem_getpages(pgcnt_t npages, int kmflag)
1089 {
1090 return (kmem_alloc(ptob(npages), kmflag));
1091 }
1092
1093 void
1094 kmem_freepages(void *addr, pgcnt_t npages)
1095 {
1096 kmem_free(addr, ptob(npages));
1097 }
1098
1099 /*
1100 * segkmem_page_create_large() allocates a large page to be used for the kmem
1101 * caches. If kpr is enabled we ask for a relocatable page unless requested
1102 * otherwise. If kpr is disabled we have to ask for a non-reloc page
1103 */
1104 static page_t *
1105 segkmem_page_create_large(void *addr, size_t size, int vmflag, void *arg)
1106 {
1107 int pgflags;
1108
1109 pgflags = PG_EXCL;
1110
1111 if (segkmem_reloc == 0 || (vmflag & VM_NORELOC))
1112 pgflags |= PG_NORELOC;
1113 if (!(vmflag & VM_NOSLEEP))
1114 pgflags |= PG_WAIT;
1115 if (vmflag & VM_PUSHPAGE)
1116 pgflags |= PG_PUSHPAGE;
1117 if (vmflag & VM_NORMALPRI)
1118 pgflags |= PG_NORMALPRI;
1119
1120 return (page_create_va_large(&kvp, (u_offset_t)(uintptr_t)addr, size,
1121 pgflags, &kvseg, addr, arg));
1122 }
1123
1124 /*
1125 * Allocate a large page to back the virtual address range
1126 * [addr, addr + size). If addr is NULL, allocate the virtual address
1127 * space as well.
1128 */
1129 static void *
1130 segkmem_xalloc_lp(vmem_t *vmp, void *inaddr, size_t size, int vmflag,
1131 uint_t attr, page_t *(*page_create_func)(void *, size_t, int, void *),
1132 void *pcarg)
1133 {
1134 caddr_t addr = inaddr, pa;
1135 size_t lpsize = segkmem_lpsize;
1136 pgcnt_t npages = btopr(size);
1137 pgcnt_t nbpages = btop(lpsize);
1138 pgcnt_t nlpages = size >> segkmem_lpshift;
1139 size_t ppasize = nbpages * sizeof (page_t *);
1140 page_t *pp, *rootpp, **ppa, *pplist = NULL;
1141 int i;
1142
1143 vmflag |= VM_NOSLEEP;
1144
1145 if (page_resv(npages, vmflag & VM_KMFLAGS) == 0) {
1146 return (NULL);
1147 }
1148
1149 /*
1150 * allocate an array we need for hat_memload_array.
1151 * we use a separate arena to avoid recursion.
1152 * we will not need this array when hat_memload_array learns pp++
1153 */
1154 if ((ppa = vmem_alloc(segkmem_ppa_arena, ppasize, vmflag)) == NULL) {
1155 goto fail_array_alloc;
1156 }
1157
1158 if (inaddr == NULL && (addr = vmem_alloc(vmp, size, vmflag)) == NULL)
1159 goto fail_vmem_alloc;
1160
1161 ASSERT(((uintptr_t)addr & (lpsize - 1)) == 0);
1162
1163 /* create all the pages */
1164 for (pa = addr, i = 0; i < nlpages; i++, pa += lpsize) {
1165 if ((pp = page_create_func(pa, lpsize, vmflag, pcarg)) == NULL)
1166 goto fail_page_create;
1167 page_list_concat(&pplist, &pp);
1168 }
1169
1170 /* at this point we have all the resource to complete the request */
1171 while ((rootpp = pplist) != NULL) {
1172 for (i = 0; i < nbpages; i++) {
1173 ASSERT(pplist != NULL);
1174 pp = pplist;
1175 page_sub(&pplist, pp);
1176 ASSERT(page_iolock_assert(pp));
1177 page_io_unlock(pp);
1178 ppa[i] = pp;
1179 }
1180 /*
1181 * Load the locked entry. It's OK to preload the entry into the
1182 * TSB since we now support large mappings in the kernel TSB.
1183 */
1184 hat_memload_array(kas.a_hat,
1185 (caddr_t)(uintptr_t)rootpp->p_offset, lpsize,
1186 ppa, (PROT_ALL & ~PROT_USER) | HAT_NOSYNC | attr,
1187 HAT_LOAD_LOCK);
1188
1189 for (--i; i >= 0; --i) {
1190 ppa[i]->p_lckcnt = 1;
1191 page_unlock(ppa[i]);
1192 }
1193 }
1194
1195 vmem_free(segkmem_ppa_arena, ppa, ppasize);
1196 return (addr);
1197
1198 fail_page_create:
1199 while ((rootpp = pplist) != NULL) {
1200 for (i = 0, pp = pplist; i < nbpages; i++, pp = pplist) {
1201 ASSERT(pp != NULL);
1202 page_sub(&pplist, pp);
1203 ASSERT(page_iolock_assert(pp));
1204 page_io_unlock(pp);
1205 }
1206 page_destroy_pages(rootpp);
1207 }
1208
1209 if (inaddr == NULL)
1210 vmem_free(vmp, addr, size);
1211
1212 fail_vmem_alloc:
1213 vmem_free(segkmem_ppa_arena, ppa, ppasize);
1214
1215 fail_array_alloc:
1216 page_unresv(npages);
1217
1218 return (NULL);
1219 }
1220
1221 static void
1222 segkmem_free_one_lp(caddr_t addr, size_t size)
1223 {
1224 page_t *pp, *rootpp = NULL;
1225 pgcnt_t pgs_left = btopr(size);
1226
1227 ASSERT(size == segkmem_lpsize);
1228
1229 hat_unload(kas.a_hat, addr, size, HAT_UNLOAD_UNLOCK);
1230
1231 for (; pgs_left > 0; addr += PAGESIZE, pgs_left--) {
1232 pp = page_lookup(&kvp, (u_offset_t)(uintptr_t)addr, SE_EXCL);
1233 if (pp == NULL)
1234 panic("segkmem_free_one_lp: page not found");
1235 ASSERT(PAGE_EXCL(pp));
1236 pp->p_lckcnt = 0;
1237 if (rootpp == NULL)
1238 rootpp = pp;
1239 }
1240 ASSERT(rootpp != NULL);
1241 page_destroy_pages(rootpp);
1242
1243 /* page_unresv() is done by the caller */
1244 }
1245
1246 /*
1247 * This function is called to import new spans into the vmem arenas like
1248 * kmem_default_arena and kmem_oversize_arena. It first tries to import
1249 * spans from large page arena - kmem_lp_arena. In order to do this it might
1250 * have to "upgrade the requested size" to kmem_lp_arena quantum. If
1251 * it was not able to satisfy the upgraded request it then calls regular
1252 * segkmem_alloc() that satisfies the request by importing from "*vmp" arena
1253 */
1254 /*ARGSUSED*/
1255 void *
1256 segkmem_alloc_lp(vmem_t *vmp, size_t *sizep, size_t align, int vmflag)
1257 {
1258 size_t size;
1259 kthread_t *t = curthread;
1260 segkmem_lpcb_t *lpcb = &segkmem_lpcb;
1261
1262 ASSERT(sizep != NULL);
1263
1264 size = *sizep;
1265
1266 if (lpcb->lp_uselp && !(t->t_flag & T_PANIC) &&
1267 !(vmflag & SEGKMEM_SHARELOCKED)) {
1268
1269 size_t kmemlp_qnt = segkmem_kmemlp_quantum;
1270 size_t asize = P2ROUNDUP(size, kmemlp_qnt);
1271 void *addr = NULL;
1272 ulong_t *lpthrtp = &lpcb->lp_throttle;
1273 ulong_t lpthrt = *lpthrtp;
1274 int dowakeup = 0;
1275 int doalloc = 1;
1276
1277 ASSERT(kmem_lp_arena != NULL);
1278 ASSERT(asize >= size);
1279
1280 if (lpthrt != 0) {
1281 /* try to update the throttle value */
1282 lpthrt = atomic_inc_ulong_nv(lpthrtp);
1283 if (lpthrt >= segkmem_lpthrottle_max) {
1284 lpthrt = atomic_cas_ulong(lpthrtp, lpthrt,
1285 segkmem_lpthrottle_max / 4);
1286 }
1287
1288 /*
1289 * when we get above throttle start do an exponential
1290 * backoff at trying large pages and reaping
1291 */
1292 if (lpthrt > segkmem_lpthrottle_start &&
1293 !ISP2(lpthrt)) {
1294 lpcb->allocs_throttled++;
1295 lpthrt--;
1296 if (ISP2(lpthrt))
1297 kmem_reap();
1298 return (segkmem_alloc(vmp, size, vmflag));
1299 }
1300 }
1301
1302 if (!(vmflag & VM_NOSLEEP) &&
1303 segkmem_heaplp_quantum >= (8 * kmemlp_qnt) &&
1304 vmem_size(kmem_lp_arena, VMEM_FREE) <= kmemlp_qnt &&
1305 asize < (segkmem_heaplp_quantum - kmemlp_qnt)) {
1306
1307 /*
1308 * we are low on free memory in kmem_lp_arena
1309 * we let only one guy to allocate heap_lp
1310 * quantum size chunk that everybody is going to
1311 * share
1312 */
1313 mutex_enter(&lpcb->lp_lock);
1314
1315 if (lpcb->lp_wait) {
1316
1317 /* we are not the first one - wait */
1318 cv_wait(&lpcb->lp_cv, &lpcb->lp_lock);
1319 if (vmem_size(kmem_lp_arena, VMEM_FREE) <
1320 kmemlp_qnt) {
1321 doalloc = 0;
1322 }
1323 } else if (vmem_size(kmem_lp_arena, VMEM_FREE) <=
1324 kmemlp_qnt) {
1325
1326 /*
1327 * we are the first one, make sure we import
1328 * a large page
1329 */
1330 if (asize == kmemlp_qnt)
1331 asize += kmemlp_qnt;
1332 dowakeup = 1;
1333 lpcb->lp_wait = 1;
1334 }
1335
1336 mutex_exit(&lpcb->lp_lock);
1337 }
1338
1339 /*
1340 * VM_ABORT flag prevents sleeps in vmem_xalloc when
1341 * large pages are not available. In that case this allocation
1342 * attempt will fail and we will retry allocation with small
1343 * pages. We also do not want to panic if this allocation fails
1344 * because we are going to retry.
1345 */
1346 if (doalloc) {
1347 addr = vmem_alloc(kmem_lp_arena, asize,
1348 (vmflag | VM_ABORT) & ~VM_PANIC);
1349
1350 if (dowakeup) {
1351 mutex_enter(&lpcb->lp_lock);
1352 ASSERT(lpcb->lp_wait != 0);
1353 lpcb->lp_wait = 0;
1354 cv_broadcast(&lpcb->lp_cv);
1355 mutex_exit(&lpcb->lp_lock);
1356 }
1357 }
1358
1359 if (addr != NULL) {
1360 *sizep = asize;
1361 *lpthrtp = 0;
1362 return (addr);
1363 }
1364
1365 if (vmflag & VM_NOSLEEP)
1366 lpcb->nosleep_allocs_failed++;
1367 else
1368 lpcb->sleep_allocs_failed++;
1369 lpcb->alloc_bytes_failed += size;
1370
1371 /* if large page throttling is not started yet do it */
1372 if (segkmem_use_lpthrottle && lpthrt == 0) {
1373 lpthrt = atomic_cas_ulong(lpthrtp, lpthrt, 1);
1374 }
1375 }
1376 return (segkmem_alloc(vmp, size, vmflag));
1377 }
1378
1379 void
1380 segkmem_free_lp(vmem_t *vmp, void *inaddr, size_t size)
1381 {
1382 if (kmem_lp_arena == NULL || !IS_KMEM_VA_LARGEPAGE((caddr_t)inaddr)) {
1383 segkmem_free(vmp, inaddr, size);
1384 } else {
1385 vmem_free(kmem_lp_arena, inaddr, size);
1386 }
1387 }
1388
1389 /*
1390 * segkmem_alloc_lpi() imports virtual memory from large page heap arena
1391 * into kmem_lp arena. In the process it maps the imported segment with
1392 * large pages
1393 */
1394 static void *
1395 segkmem_alloc_lpi(vmem_t *vmp, size_t size, int vmflag)
1396 {
1397 segkmem_lpcb_t *lpcb = &segkmem_lpcb;
1398 void *addr;
1399
1400 ASSERT(size != 0);
1401 ASSERT(vmp == heap_lp_arena);
1402
1403 /* do not allow large page heap grow beyound limits */
1404 if (vmem_size(vmp, VMEM_ALLOC) >= segkmem_kmemlp_max) {
1405 lpcb->allocs_limited++;
1406 return (NULL);
1407 }
1408
1409 addr = segkmem_xalloc_lp(vmp, NULL, size, vmflag, 0,
1410 segkmem_page_create_large, NULL);
1411 return (addr);
1412 }
1413
1414 /*
1415 * segkmem_free_lpi() returns virtual memory back into large page heap arena
1416 * from kmem_lp arena. Beore doing this it unmaps the segment and frees
1417 * large pages used to map it.
1418 */
1419 static void
1420 segkmem_free_lpi(vmem_t *vmp, void *inaddr, size_t size)
1421 {
1422 pgcnt_t nlpages = size >> segkmem_lpshift;
1423 size_t lpsize = segkmem_lpsize;
1424 caddr_t addr = inaddr;
1425 pgcnt_t npages = btopr(size);
1426 int i;
1427
1428 ASSERT(vmp == heap_lp_arena);
1429 ASSERT(IS_KMEM_VA_LARGEPAGE(addr));
1430 ASSERT(((uintptr_t)inaddr & (lpsize - 1)) == 0);
1431
1432 for (i = 0; i < nlpages; i++) {
1433 segkmem_free_one_lp(addr, lpsize);
1434 addr += lpsize;
1435 }
1436
1437 page_unresv(npages);
1438
1439 vmem_free(vmp, inaddr, size);
1440 }
1441
1442 /*
1443 * This function is called at system boot time by kmem_init right after
1444 * /etc/system file has been read. It checks based on hardware configuration
1445 * and /etc/system settings if system is going to use large pages. The
1446 * initialiazation necessary to actually start using large pages
1447 * happens later in the process after segkmem_heap_lp_init() is called.
1448 */
1449 int
1450 segkmem_lpsetup()
1451 {
1452 int use_large_pages = 0;
1453
1454 #ifdef __sparc
1455
1456 size_t memtotal = physmem * PAGESIZE;
1457
1458 if (heap_lp_base == NULL) {
1459 segkmem_lpsize = PAGESIZE;
1460 return (0);
1461 }
1462
1463 /* get a platform dependent value of large page size for kernel heap */
1464 segkmem_lpsize = get_segkmem_lpsize(segkmem_lpsize);
1465
1466 if (segkmem_lpsize <= PAGESIZE) {
1467 /*
1468 * put virtual space reserved for the large page kernel
1469 * back to the regular heap
1470 */
1471 vmem_xfree(heap_arena, heap_lp_base,
1472 heap_lp_end - heap_lp_base);
1473 heap_lp_base = NULL;
1474 heap_lp_end = NULL;
1475 segkmem_lpsize = PAGESIZE;
1476 return (0);
1477 }
1478
1479 /* set heap_lp quantum if necessary */
1480 if (segkmem_heaplp_quantum == 0 || !ISP2(segkmem_heaplp_quantum) ||
1481 P2PHASE(segkmem_heaplp_quantum, segkmem_lpsize)) {
1482 segkmem_heaplp_quantum = segkmem_lpsize;
1483 }
1484
1485 /* set kmem_lp quantum if necessary */
1486 if (segkmem_kmemlp_quantum == 0 || !ISP2(segkmem_kmemlp_quantum) ||
1487 segkmem_kmemlp_quantum > segkmem_heaplp_quantum) {
1488 segkmem_kmemlp_quantum = segkmem_heaplp_quantum;
1489 }
1490
1491 /* set total amount of memory allowed for large page kernel heap */
1492 if (segkmem_kmemlp_max == 0) {
1493 if (segkmem_kmemlp_pcnt == 0 || segkmem_kmemlp_pcnt > 100)
1494 segkmem_kmemlp_pcnt = 12;
1495 segkmem_kmemlp_max = (memtotal * segkmem_kmemlp_pcnt) / 100;
1496 }
1497 segkmem_kmemlp_max = P2ROUNDUP(segkmem_kmemlp_max,
1498 segkmem_heaplp_quantum);
1499
1500 /* fix lp kmem preallocation request if necesssary */
1501 if (segkmem_kmemlp_min) {
1502 segkmem_kmemlp_min = P2ROUNDUP(segkmem_kmemlp_min,
1503 segkmem_heaplp_quantum);
1504 if (segkmem_kmemlp_min > segkmem_kmemlp_max)
1505 segkmem_kmemlp_min = segkmem_kmemlp_max;
1506 }
1507
1508 use_large_pages = 1;
1509 segkmem_lpszc = page_szc(segkmem_lpsize);
1510 segkmem_lpshift = page_get_shift(segkmem_lpszc);
1511
1512 #endif
1513 return (use_large_pages);
1514 }
1515
1516 void
1517 segkmem_zio_init(void *zio_mem_base, size_t zio_mem_size)
1518 {
1519 ASSERT(zio_mem_base != NULL);
1520 ASSERT(zio_mem_size != 0);
1521
1522 /*
1523 * To reduce VA space fragmentation, we set up quantum caches for the
1524 * smaller sizes; we chose 32k because that translates to 128k VA
1525 * slabs, which matches nicely with the common 128k zio_data bufs.
1526 */
1527 zio_arena = vmem_create("zfs_file_data", zio_mem_base, zio_mem_size,
1528 PAGESIZE, NULL, NULL, NULL, 32 * 1024, VM_SLEEP);
1529
1530 zio_alloc_arena = vmem_create("zfs_file_data_buf", NULL, 0, PAGESIZE,
1531 segkmem_zio_alloc, segkmem_zio_free, zio_arena, 0, VM_SLEEP);
1532
1533 ASSERT(zio_arena != NULL);
1534 ASSERT(zio_alloc_arena != NULL);
1535 }
1536
1537 #ifdef __sparc
1538
1539
1540 static void *
1541 segkmem_alloc_ppa(vmem_t *vmp, size_t size, int vmflag)
1542 {
1543 size_t ppaquantum = btopr(segkmem_lpsize) * sizeof (page_t *);
1544 void *addr;
1545
1546 if (ppaquantum <= PAGESIZE)
1547 return (segkmem_alloc(vmp, size, vmflag));
1548
1549 ASSERT((size & (ppaquantum - 1)) == 0);
1550
1551 addr = vmem_xalloc(vmp, size, ppaquantum, 0, 0, NULL, NULL, vmflag);
1552 if (addr != NULL && segkmem_xalloc(vmp, addr, size, vmflag, 0,
1553 segkmem_page_create, NULL) == NULL) {
1554 vmem_xfree(vmp, addr, size);
1555 addr = NULL;
1556 }
1557
1558 return (addr);
1559 }
1560
1561 static void
1562 segkmem_free_ppa(vmem_t *vmp, void *addr, size_t size)
1563 {
1564 size_t ppaquantum = btopr(segkmem_lpsize) * sizeof (page_t *);
1565
1566 ASSERT(addr != NULL);
1567
1568 if (ppaquantum <= PAGESIZE) {
1569 segkmem_free(vmp, addr, size);
1570 } else {
1571 segkmem_free(NULL, addr, size);
1572 vmem_xfree(vmp, addr, size);
1573 }
1574 }
1575
1576 void
1577 segkmem_heap_lp_init()
1578 {
1579 segkmem_lpcb_t *lpcb = &segkmem_lpcb;
1580 size_t heap_lp_size = heap_lp_end - heap_lp_base;
1581 size_t lpsize = segkmem_lpsize;
1582 size_t ppaquantum;
1583 void *addr;
1584
1585 if (segkmem_lpsize <= PAGESIZE) {
1586 ASSERT(heap_lp_base == NULL);
1587 ASSERT(heap_lp_end == NULL);
1588 return;
1589 }
1590
1591 ASSERT(segkmem_heaplp_quantum >= lpsize);
1592 ASSERT((segkmem_heaplp_quantum & (lpsize - 1)) == 0);
1593 ASSERT(lpcb->lp_uselp == 0);
1594 ASSERT(heap_lp_base != NULL);
1595 ASSERT(heap_lp_end != NULL);
1596 ASSERT(heap_lp_base < heap_lp_end);
1597 ASSERT(heap_lp_arena == NULL);
1598 ASSERT(((uintptr_t)heap_lp_base & (lpsize - 1)) == 0);
1599 ASSERT(((uintptr_t)heap_lp_end & (lpsize - 1)) == 0);
1600
1601 /* create large page heap arena */
1602 heap_lp_arena = vmem_create("heap_lp", heap_lp_base, heap_lp_size,
1603 segkmem_heaplp_quantum, NULL, NULL, NULL, 0, VM_SLEEP);
1604
1605 ASSERT(heap_lp_arena != NULL);
1606
1607 /* This arena caches memory already mapped by large pages */
1608 kmem_lp_arena = vmem_create("kmem_lp", NULL, 0, segkmem_kmemlp_quantum,
1609 segkmem_alloc_lpi, segkmem_free_lpi, heap_lp_arena, 0, VM_SLEEP);
1610
1611 ASSERT(kmem_lp_arena != NULL);
1612
1613 mutex_init(&lpcb->lp_lock, NULL, MUTEX_DEFAULT, NULL);
1614 cv_init(&lpcb->lp_cv, NULL, CV_DEFAULT, NULL);
1615
1616 /*
1617 * this arena is used for the array of page_t pointers necessary
1618 * to call hat_mem_load_array
1619 */
1620 ppaquantum = btopr(lpsize) * sizeof (page_t *);
1621 segkmem_ppa_arena = vmem_create("segkmem_ppa", NULL, 0, ppaquantum,
1622 segkmem_alloc_ppa, segkmem_free_ppa, heap_arena, ppaquantum,
1623 VM_SLEEP);
1624
1625 ASSERT(segkmem_ppa_arena != NULL);
1626
1627 /* prealloacate some memory for the lp kernel heap */
1628 if (segkmem_kmemlp_min) {
1629
1630 ASSERT(P2PHASE(segkmem_kmemlp_min,
1631 segkmem_heaplp_quantum) == 0);
1632
1633 if ((addr = segkmem_alloc_lpi(heap_lp_arena,
1634 segkmem_kmemlp_min, VM_SLEEP)) != NULL) {
1635
1636 addr = vmem_add(kmem_lp_arena, addr,
1637 segkmem_kmemlp_min, VM_SLEEP);
1638 ASSERT(addr != NULL);
1639 }
1640 }
1641
1642 lpcb->lp_uselp = 1;
1643 }
1644
1645 #endif