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const-ify make segment ops structures
There is no reason to keep the segment ops structures writable.
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--- old/usr/src/uts/common/vm/seg_spt.c
+++ new/usr/src/uts/common/vm/seg_spt.c
1 1 /*
2 2 * CDDL HEADER START
3 3 *
4 4 * The contents of this file are subject to the terms of the
5 5 * Common Development and Distribution License (the "License").
6 6 * You may not use this file except in compliance with the License.
7 7 *
8 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 9 * or http://www.opensolaris.org/os/licensing.
10 10 * See the License for the specific language governing permissions
11 11 * and limitations under the License.
12 12 *
13 13 * When distributing Covered Code, include this CDDL HEADER in each
14 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 15 * If applicable, add the following below this CDDL HEADER, with the
16 16 * fields enclosed by brackets "[]" replaced with your own identifying
17 17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 18 *
19 19 * CDDL HEADER END
20 20 */
21 21 /*
22 22 * Copyright (c) 1993, 2010, Oracle and/or its affiliates. All rights reserved.
23 23 */
24 24
25 25 #include <sys/param.h>
26 26 #include <sys/user.h>
27 27 #include <sys/mman.h>
28 28 #include <sys/kmem.h>
29 29 #include <sys/sysmacros.h>
30 30 #include <sys/cmn_err.h>
31 31 #include <sys/systm.h>
32 32 #include <sys/tuneable.h>
33 33 #include <vm/hat.h>
34 34 #include <vm/seg.h>
35 35 #include <vm/as.h>
36 36 #include <vm/anon.h>
37 37 #include <vm/page.h>
38 38 #include <sys/buf.h>
39 39 #include <sys/swap.h>
40 40 #include <sys/atomic.h>
41 41 #include <vm/seg_spt.h>
42 42 #include <sys/debug.h>
43 43 #include <sys/vtrace.h>
44 44 #include <sys/shm.h>
45 45 #include <sys/shm_impl.h>
46 46 #include <sys/lgrp.h>
47 47 #include <sys/vmsystm.h>
48 48 #include <sys/policy.h>
49 49 #include <sys/project.h>
50 50 #include <sys/tnf_probe.h>
51 51 #include <sys/zone.h>
52 52
53 53 #define SEGSPTADDR (caddr_t)0x0
54 54
55 55 /*
56 56 * # pages used for spt
57 57 */
58 58 size_t spt_used;
59 59
60 60 /*
61 61 * segspt_minfree is the memory left for system after ISM
62 62 * locked its pages; it is set up to 5% of availrmem in
63 63 * sptcreate when ISM is created. ISM should not use more
64 64 * than ~90% of availrmem; if it does, then the performance
65 65 * of the system may decrease. Machines with large memories may
66 66 * be able to use up more memory for ISM so we set the default
67 67 * segspt_minfree to 5% (which gives ISM max 95% of availrmem.
68 68 * If somebody wants even more memory for ISM (risking hanging
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69 69 * the system) they can patch the segspt_minfree to smaller number.
70 70 */
71 71 pgcnt_t segspt_minfree = 0;
72 72
73 73 static int segspt_create(struct seg *seg, caddr_t argsp);
74 74 static int segspt_unmap(struct seg *seg, caddr_t raddr, size_t ssize);
75 75 static void segspt_free(struct seg *seg);
76 76 static void segspt_free_pages(struct seg *seg, caddr_t addr, size_t len);
77 77 static lgrp_mem_policy_info_t *segspt_getpolicy(struct seg *seg, caddr_t addr);
78 78
79 -struct seg_ops segspt_ops = {
79 +const struct seg_ops segspt_ops = {
80 80 .unmap = segspt_unmap,
81 81 .free = segspt_free,
82 82 .getpolicy = segspt_getpolicy,
83 83 };
84 84
85 85 static int segspt_shmdup(struct seg *seg, struct seg *newseg);
86 86 static int segspt_shmunmap(struct seg *seg, caddr_t raddr, size_t ssize);
87 87 static void segspt_shmfree(struct seg *seg);
88 88 static faultcode_t segspt_shmfault(struct hat *hat, struct seg *seg,
89 89 caddr_t addr, size_t len, enum fault_type type, enum seg_rw rw);
90 90 static faultcode_t segspt_shmfaulta(struct seg *seg, caddr_t addr);
91 91 static int segspt_shmsetprot(register struct seg *seg, register caddr_t addr,
92 92 register size_t len, register uint_t prot);
93 93 static int segspt_shmcheckprot(struct seg *seg, caddr_t addr, size_t size,
94 94 uint_t prot);
95 95 static int segspt_shmkluster(struct seg *seg, caddr_t addr, ssize_t delta);
96 96 static size_t segspt_shmincore(struct seg *seg, caddr_t addr, size_t len,
97 97 register char *vec);
98 98 static int segspt_shmsync(struct seg *seg, register caddr_t addr, size_t len,
99 99 int attr, uint_t flags);
100 100 static int segspt_shmlockop(struct seg *seg, caddr_t addr, size_t len,
101 101 int attr, int op, ulong_t *lockmap, size_t pos);
102 102 static int segspt_shmgetprot(struct seg *seg, caddr_t addr, size_t len,
103 103 uint_t *protv);
104 104 static u_offset_t segspt_shmgetoffset(struct seg *seg, caddr_t addr);
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105 105 static int segspt_shmgettype(struct seg *seg, caddr_t addr);
106 106 static int segspt_shmgetvp(struct seg *seg, caddr_t addr, struct vnode **vpp);
107 107 static int segspt_shmadvise(struct seg *seg, caddr_t addr, size_t len,
108 108 uint_t behav);
109 109 static void segspt_shmdump(struct seg *seg);
110 110 static int segspt_shmpagelock(struct seg *, caddr_t, size_t,
111 111 struct page ***, enum lock_type, enum seg_rw);
112 112 static int segspt_shmgetmemid(struct seg *, caddr_t, memid_t *);
113 113 static lgrp_mem_policy_info_t *segspt_shmgetpolicy(struct seg *, caddr_t);
114 114
115 -struct seg_ops segspt_shmops = {
115 +const struct seg_ops segspt_shmops = {
116 116 .dup = segspt_shmdup,
117 117 .unmap = segspt_shmunmap,
118 118 .free = segspt_shmfree,
119 119 .fault = segspt_shmfault,
120 120 .faulta = segspt_shmfaulta,
121 121 .setprot = segspt_shmsetprot,
122 122 .checkprot = segspt_shmcheckprot,
123 123 .kluster = segspt_shmkluster,
124 124 .sync = segspt_shmsync,
125 125 .incore = segspt_shmincore,
126 126 .lockop = segspt_shmlockop,
127 127 .getprot = segspt_shmgetprot,
128 128 .getoffset = segspt_shmgetoffset,
129 129 .gettype = segspt_shmgettype,
130 130 .getvp = segspt_shmgetvp,
131 131 .advise = segspt_shmadvise,
132 132 .dump = segspt_shmdump,
133 133 .pagelock = segspt_shmpagelock,
134 134 .getmemid = segspt_shmgetmemid,
135 135 .getpolicy = segspt_shmgetpolicy,
136 136 };
137 137
138 138 static void segspt_purge(struct seg *seg);
139 139 static int segspt_reclaim(void *, caddr_t, size_t, struct page **,
140 140 enum seg_rw, int);
141 141 static int spt_anon_getpages(struct seg *seg, caddr_t addr, size_t len,
142 142 page_t **ppa);
143 143
144 144
145 145
146 146 /*ARGSUSED*/
147 147 int
148 148 sptcreate(size_t size, struct seg **sptseg, struct anon_map *amp,
149 149 uint_t prot, uint_t flags, uint_t share_szc)
150 150 {
151 151 int err;
152 152 struct as *newas;
153 153 struct segspt_crargs sptcargs;
154 154
155 155 #ifdef DEBUG
156 156 TNF_PROBE_1(sptcreate, "spt", /* CSTYLED */,
157 157 tnf_ulong, size, size );
158 158 #endif
159 159 if (segspt_minfree == 0) /* leave min 5% of availrmem for */
160 160 segspt_minfree = availrmem/20; /* for the system */
161 161
162 162 if (!hat_supported(HAT_SHARED_PT, (void *)0))
163 163 return (EINVAL);
164 164
165 165 /*
166 166 * get a new as for this shared memory segment
167 167 */
168 168 newas = as_alloc();
169 169 newas->a_proc = NULL;
170 170 sptcargs.amp = amp;
171 171 sptcargs.prot = prot;
172 172 sptcargs.flags = flags;
173 173 sptcargs.szc = share_szc;
174 174 /*
175 175 * create a shared page table (spt) segment
176 176 */
177 177
178 178 if (err = as_map(newas, SEGSPTADDR, size, segspt_create, &sptcargs)) {
179 179 as_free(newas);
180 180 return (err);
181 181 }
182 182 *sptseg = sptcargs.seg_spt;
183 183 return (0);
184 184 }
185 185
186 186 void
187 187 sptdestroy(struct as *as, struct anon_map *amp)
188 188 {
189 189
190 190 #ifdef DEBUG
191 191 TNF_PROBE_0(sptdestroy, "spt", /* CSTYLED */);
192 192 #endif
193 193 (void) as_unmap(as, SEGSPTADDR, amp->size);
194 194 as_free(as);
195 195 }
196 196
197 197 /*
198 198 * called from seg_free().
199 199 * free (i.e., unlock, unmap, return to free list)
200 200 * all the pages in the given seg.
201 201 */
202 202 void
203 203 segspt_free(struct seg *seg)
204 204 {
205 205 struct spt_data *sptd = (struct spt_data *)seg->s_data;
206 206
207 207 ASSERT(seg->s_as && AS_WRITE_HELD(seg->s_as, &seg->s_as->a_lock));
208 208
209 209 if (sptd != NULL) {
210 210 if (sptd->spt_realsize)
211 211 segspt_free_pages(seg, seg->s_base, sptd->spt_realsize);
212 212
213 213 if (sptd->spt_ppa_lckcnt)
214 214 kmem_free(sptd->spt_ppa_lckcnt,
215 215 sizeof (*sptd->spt_ppa_lckcnt)
216 216 * btopr(sptd->spt_amp->size));
217 217 kmem_free(sptd->spt_vp, sizeof (*sptd->spt_vp));
218 218 cv_destroy(&sptd->spt_cv);
219 219 mutex_destroy(&sptd->spt_lock);
220 220 kmem_free(sptd, sizeof (*sptd));
221 221 }
222 222 }
223 223
224 224 /*ARGSUSED*/
225 225 static int
226 226 segspt_shmsync(struct seg *seg, caddr_t addr, size_t len, int attr,
227 227 uint_t flags)
228 228 {
229 229 ASSERT(seg->s_as && AS_LOCK_HELD(seg->s_as, &seg->s_as->a_lock));
230 230
231 231 return (0);
232 232 }
233 233
234 234 /*ARGSUSED*/
235 235 static size_t
236 236 segspt_shmincore(struct seg *seg, caddr_t addr, size_t len, char *vec)
237 237 {
238 238 caddr_t eo_seg;
239 239 pgcnt_t npages;
240 240 struct shm_data *shmd = (struct shm_data *)seg->s_data;
241 241 struct seg *sptseg;
242 242 struct spt_data *sptd;
243 243
244 244 ASSERT(seg->s_as && AS_LOCK_HELD(seg->s_as, &seg->s_as->a_lock));
245 245 #ifdef lint
246 246 seg = seg;
247 247 #endif
248 248 sptseg = shmd->shm_sptseg;
249 249 sptd = sptseg->s_data;
250 250
251 251 if ((sptd->spt_flags & SHM_PAGEABLE) == 0) {
252 252 eo_seg = addr + len;
253 253 while (addr < eo_seg) {
254 254 /* page exists, and it's locked. */
255 255 *vec++ = SEG_PAGE_INCORE | SEG_PAGE_LOCKED |
256 256 SEG_PAGE_ANON;
257 257 addr += PAGESIZE;
258 258 }
259 259 return (len);
260 260 } else {
261 261 struct anon_map *amp = shmd->shm_amp;
262 262 struct anon *ap;
263 263 page_t *pp;
264 264 pgcnt_t anon_index;
265 265 struct vnode *vp;
266 266 u_offset_t off;
267 267 ulong_t i;
268 268 int ret;
269 269 anon_sync_obj_t cookie;
270 270
271 271 addr = (caddr_t)((uintptr_t)addr & (uintptr_t)PAGEMASK);
272 272 anon_index = seg_page(seg, addr);
273 273 npages = btopr(len);
274 274 if (anon_index + npages > btopr(shmd->shm_amp->size)) {
275 275 return (EINVAL);
276 276 }
277 277 ANON_LOCK_ENTER(&->a_rwlock, RW_READER);
278 278 for (i = 0; i < npages; i++, anon_index++) {
279 279 ret = 0;
280 280 anon_array_enter(amp, anon_index, &cookie);
281 281 ap = anon_get_ptr(amp->ahp, anon_index);
282 282 if (ap != NULL) {
283 283 swap_xlate(ap, &vp, &off);
284 284 anon_array_exit(&cookie);
285 285 pp = page_lookup_nowait(vp, off, SE_SHARED);
286 286 if (pp != NULL) {
287 287 ret |= SEG_PAGE_INCORE | SEG_PAGE_ANON;
288 288 page_unlock(pp);
289 289 }
290 290 } else {
291 291 anon_array_exit(&cookie);
292 292 }
293 293 if (shmd->shm_vpage[anon_index] & DISM_PG_LOCKED) {
294 294 ret |= SEG_PAGE_LOCKED;
295 295 }
296 296 *vec++ = (char)ret;
297 297 }
298 298 ANON_LOCK_EXIT(&->a_rwlock);
299 299 return (len);
300 300 }
301 301 }
302 302
303 303 static int
304 304 segspt_unmap(struct seg *seg, caddr_t raddr, size_t ssize)
305 305 {
306 306 size_t share_size;
307 307
308 308 ASSERT(seg->s_as && AS_WRITE_HELD(seg->s_as, &seg->s_as->a_lock));
309 309
310 310 /*
311 311 * seg.s_size may have been rounded up to the largest page size
312 312 * in shmat().
313 313 * XXX This should be cleanedup. sptdestroy should take a length
314 314 * argument which should be the same as sptcreate. Then
315 315 * this rounding would not be needed (or is done in shm.c)
316 316 * Only the check for full segment will be needed.
317 317 *
318 318 * XXX -- shouldn't raddr == 0 always? These tests don't seem
319 319 * to be useful at all.
320 320 */
321 321 share_size = page_get_pagesize(seg->s_szc);
322 322 ssize = P2ROUNDUP(ssize, share_size);
323 323
324 324 if (raddr == seg->s_base && ssize == seg->s_size) {
325 325 seg_free(seg);
326 326 return (0);
327 327 } else
328 328 return (EINVAL);
329 329 }
330 330
331 331 int
332 332 segspt_create(struct seg *seg, caddr_t argsp)
333 333 {
334 334 int err;
335 335 caddr_t addr = seg->s_base;
336 336 struct spt_data *sptd;
337 337 struct segspt_crargs *sptcargs = (struct segspt_crargs *)argsp;
338 338 struct anon_map *amp = sptcargs->amp;
339 339 struct kshmid *sp = amp->a_sp;
340 340 struct cred *cred = CRED();
341 341 ulong_t i, j, anon_index = 0;
342 342 pgcnt_t npages = btopr(amp->size);
343 343 struct vnode *vp;
344 344 page_t **ppa;
345 345 uint_t hat_flags;
346 346 size_t pgsz;
347 347 pgcnt_t pgcnt;
348 348 caddr_t a;
349 349 pgcnt_t pidx;
350 350 size_t sz;
351 351 proc_t *procp = curproc;
352 352 rctl_qty_t lockedbytes = 0;
353 353 kproject_t *proj;
354 354
355 355 /*
356 356 * We are holding the a_lock on the underlying dummy as,
357 357 * so we can make calls to the HAT layer.
358 358 */
359 359 ASSERT(seg->s_as && AS_WRITE_HELD(seg->s_as, &seg->s_as->a_lock));
360 360 ASSERT(sp != NULL);
361 361
362 362 #ifdef DEBUG
363 363 TNF_PROBE_2(segspt_create, "spt", /* CSTYLED */,
364 364 tnf_opaque, addr, addr, tnf_ulong, len, seg->s_size);
365 365 #endif
366 366 if ((sptcargs->flags & SHM_PAGEABLE) == 0) {
367 367 if (err = anon_swap_adjust(npages))
368 368 return (err);
369 369 }
370 370 err = ENOMEM;
371 371
372 372 if ((sptd = kmem_zalloc(sizeof (*sptd), KM_NOSLEEP)) == NULL)
373 373 goto out1;
374 374
375 375 if ((sptcargs->flags & SHM_PAGEABLE) == 0) {
376 376 if ((ppa = kmem_zalloc(((sizeof (page_t *)) * npages),
377 377 KM_NOSLEEP)) == NULL)
378 378 goto out2;
379 379 }
380 380
381 381 mutex_init(&sptd->spt_lock, NULL, MUTEX_DEFAULT, NULL);
382 382
383 383 if ((vp = kmem_zalloc(sizeof (*vp), KM_NOSLEEP)) == NULL)
384 384 goto out3;
385 385
386 386 seg->s_ops = &segspt_ops;
387 387 sptd->spt_vp = vp;
388 388 sptd->spt_amp = amp;
389 389 sptd->spt_prot = sptcargs->prot;
390 390 sptd->spt_flags = sptcargs->flags;
391 391 seg->s_data = (caddr_t)sptd;
392 392 sptd->spt_ppa = NULL;
393 393 sptd->spt_ppa_lckcnt = NULL;
394 394 seg->s_szc = sptcargs->szc;
395 395 cv_init(&sptd->spt_cv, NULL, CV_DEFAULT, NULL);
396 396 sptd->spt_gen = 0;
397 397
398 398 ANON_LOCK_ENTER(&->a_rwlock, RW_WRITER);
399 399 if (seg->s_szc > amp->a_szc) {
400 400 amp->a_szc = seg->s_szc;
401 401 }
402 402 ANON_LOCK_EXIT(&->a_rwlock);
403 403
404 404 /*
405 405 * Set policy to affect initial allocation of pages in
406 406 * anon_map_createpages()
407 407 */
408 408 (void) lgrp_shm_policy_set(LGRP_MEM_POLICY_DEFAULT, amp, anon_index,
409 409 NULL, 0, ptob(npages));
410 410
411 411 if (sptcargs->flags & SHM_PAGEABLE) {
412 412 size_t share_sz;
413 413 pgcnt_t new_npgs, more_pgs;
414 414 struct anon_hdr *nahp;
415 415 zone_t *zone;
416 416
417 417 share_sz = page_get_pagesize(seg->s_szc);
418 418 if (!IS_P2ALIGNED(amp->size, share_sz)) {
419 419 /*
420 420 * We are rounding up the size of the anon array
421 421 * on 4 M boundary because we always create 4 M
422 422 * of page(s) when locking, faulting pages and we
423 423 * don't have to check for all corner cases e.g.
424 424 * if there is enough space to allocate 4 M
425 425 * page.
426 426 */
427 427 new_npgs = btop(P2ROUNDUP(amp->size, share_sz));
428 428 more_pgs = new_npgs - npages;
429 429
430 430 /*
431 431 * The zone will never be NULL, as a fully created
432 432 * shm always has an owning zone.
433 433 */
434 434 zone = sp->shm_perm.ipc_zone_ref.zref_zone;
435 435 ASSERT(zone != NULL);
436 436 if (anon_resv_zone(ptob(more_pgs), zone) == 0) {
437 437 err = ENOMEM;
438 438 goto out4;
439 439 }
440 440
441 441 nahp = anon_create(new_npgs, ANON_SLEEP);
442 442 ANON_LOCK_ENTER(&->a_rwlock, RW_WRITER);
443 443 (void) anon_copy_ptr(amp->ahp, 0, nahp, 0, npages,
444 444 ANON_SLEEP);
445 445 anon_release(amp->ahp, npages);
446 446 amp->ahp = nahp;
447 447 ASSERT(amp->swresv == ptob(npages));
448 448 amp->swresv = amp->size = ptob(new_npgs);
449 449 ANON_LOCK_EXIT(&->a_rwlock);
450 450 npages = new_npgs;
451 451 }
452 452
453 453 sptd->spt_ppa_lckcnt = kmem_zalloc(npages *
454 454 sizeof (*sptd->spt_ppa_lckcnt), KM_SLEEP);
455 455 sptd->spt_pcachecnt = 0;
456 456 sptd->spt_realsize = ptob(npages);
457 457 sptcargs->seg_spt = seg;
458 458 return (0);
459 459 }
460 460
461 461 /*
462 462 * get array of pages for each anon slot in amp
463 463 */
464 464 if ((err = anon_map_createpages(amp, anon_index, ptob(npages), ppa,
465 465 seg, addr, S_CREATE, cred)) != 0)
466 466 goto out4;
467 467
468 468 mutex_enter(&sp->shm_mlock);
469 469
470 470 /* May be partially locked, so, count bytes to charge for locking */
471 471 for (i = 0; i < npages; i++)
472 472 if (ppa[i]->p_lckcnt == 0)
473 473 lockedbytes += PAGESIZE;
474 474
475 475 proj = sp->shm_perm.ipc_proj;
476 476
477 477 if (lockedbytes > 0) {
478 478 mutex_enter(&procp->p_lock);
479 479 if (rctl_incr_locked_mem(procp, proj, lockedbytes, 0)) {
480 480 mutex_exit(&procp->p_lock);
481 481 mutex_exit(&sp->shm_mlock);
482 482 for (i = 0; i < npages; i++)
483 483 page_unlock(ppa[i]);
484 484 err = ENOMEM;
485 485 goto out4;
486 486 }
487 487 mutex_exit(&procp->p_lock);
488 488 }
489 489
490 490 /*
491 491 * addr is initial address corresponding to the first page on ppa list
492 492 */
493 493 for (i = 0; i < npages; i++) {
494 494 /* attempt to lock all pages */
495 495 if (page_pp_lock(ppa[i], 0, 1) == 0) {
496 496 /*
497 497 * if unable to lock any page, unlock all
498 498 * of them and return error
499 499 */
500 500 for (j = 0; j < i; j++)
501 501 page_pp_unlock(ppa[j], 0, 1);
502 502 for (i = 0; i < npages; i++)
503 503 page_unlock(ppa[i]);
504 504 rctl_decr_locked_mem(NULL, proj, lockedbytes, 0);
505 505 mutex_exit(&sp->shm_mlock);
506 506 err = ENOMEM;
507 507 goto out4;
508 508 }
509 509 }
510 510 mutex_exit(&sp->shm_mlock);
511 511
512 512 /*
513 513 * Some platforms assume that ISM mappings are HAT_LOAD_LOCK
514 514 * for the entire life of the segment. For example platforms
515 515 * that do not support Dynamic Reconfiguration.
516 516 */
517 517 hat_flags = HAT_LOAD_SHARE;
518 518 if (!hat_supported(HAT_DYNAMIC_ISM_UNMAP, NULL))
519 519 hat_flags |= HAT_LOAD_LOCK;
520 520
521 521 /*
522 522 * Load translations one lare page at a time
523 523 * to make sure we don't create mappings bigger than
524 524 * segment's size code in case underlying pages
525 525 * are shared with segvn's segment that uses bigger
526 526 * size code than we do.
527 527 */
528 528 pgsz = page_get_pagesize(seg->s_szc);
529 529 pgcnt = page_get_pagecnt(seg->s_szc);
530 530 for (a = addr, pidx = 0; pidx < npages; a += pgsz, pidx += pgcnt) {
531 531 sz = MIN(pgsz, ptob(npages - pidx));
532 532 hat_memload_array(seg->s_as->a_hat, a, sz,
533 533 &ppa[pidx], sptd->spt_prot, hat_flags);
534 534 }
535 535
536 536 /*
537 537 * On platforms that do not support HAT_DYNAMIC_ISM_UNMAP,
538 538 * we will leave the pages locked SE_SHARED for the life
539 539 * of the ISM segment. This will prevent any calls to
540 540 * hat_pageunload() on this ISM segment for those platforms.
541 541 */
542 542 if (!(hat_flags & HAT_LOAD_LOCK)) {
543 543 /*
544 544 * On platforms that support HAT_DYNAMIC_ISM_UNMAP,
545 545 * we no longer need to hold the SE_SHARED lock on the pages,
546 546 * since L_PAGELOCK and F_SOFTLOCK calls will grab the
547 547 * SE_SHARED lock on the pages as necessary.
548 548 */
549 549 for (i = 0; i < npages; i++)
550 550 page_unlock(ppa[i]);
551 551 }
552 552 sptd->spt_pcachecnt = 0;
553 553 kmem_free(ppa, ((sizeof (page_t *)) * npages));
554 554 sptd->spt_realsize = ptob(npages);
555 555 atomic_add_long(&spt_used, npages);
556 556 sptcargs->seg_spt = seg;
557 557 return (0);
558 558
559 559 out4:
560 560 seg->s_data = NULL;
561 561 kmem_free(vp, sizeof (*vp));
562 562 cv_destroy(&sptd->spt_cv);
563 563 out3:
564 564 mutex_destroy(&sptd->spt_lock);
565 565 if ((sptcargs->flags & SHM_PAGEABLE) == 0)
566 566 kmem_free(ppa, (sizeof (*ppa) * npages));
567 567 out2:
568 568 kmem_free(sptd, sizeof (*sptd));
569 569 out1:
570 570 if ((sptcargs->flags & SHM_PAGEABLE) == 0)
571 571 anon_swap_restore(npages);
572 572 return (err);
573 573 }
574 574
575 575 /*ARGSUSED*/
576 576 void
577 577 segspt_free_pages(struct seg *seg, caddr_t addr, size_t len)
578 578 {
579 579 struct page *pp;
580 580 struct spt_data *sptd = (struct spt_data *)seg->s_data;
581 581 pgcnt_t npages;
582 582 ulong_t anon_idx;
583 583 struct anon_map *amp;
584 584 struct anon *ap;
585 585 struct vnode *vp;
586 586 u_offset_t off;
587 587 uint_t hat_flags;
588 588 int root = 0;
589 589 pgcnt_t pgs, curnpgs = 0;
590 590 page_t *rootpp;
591 591 rctl_qty_t unlocked_bytes = 0;
592 592 kproject_t *proj;
593 593 kshmid_t *sp;
594 594
595 595 ASSERT(seg->s_as && AS_WRITE_HELD(seg->s_as, &seg->s_as->a_lock));
596 596
597 597 len = P2ROUNDUP(len, PAGESIZE);
598 598
599 599 npages = btop(len);
600 600
601 601 hat_flags = HAT_UNLOAD_UNLOCK | HAT_UNLOAD_UNMAP;
602 602 if ((hat_supported(HAT_DYNAMIC_ISM_UNMAP, (void *)0)) ||
603 603 (sptd->spt_flags & SHM_PAGEABLE)) {
604 604 hat_flags = HAT_UNLOAD_UNMAP;
605 605 }
606 606
607 607 hat_unload(seg->s_as->a_hat, addr, len, hat_flags);
608 608
609 609 amp = sptd->spt_amp;
610 610 if (sptd->spt_flags & SHM_PAGEABLE)
611 611 npages = btop(amp->size);
612 612
613 613 ASSERT(amp != NULL);
614 614
615 615 if ((sptd->spt_flags & SHM_PAGEABLE) == 0) {
616 616 sp = amp->a_sp;
617 617 proj = sp->shm_perm.ipc_proj;
618 618 mutex_enter(&sp->shm_mlock);
619 619 }
620 620 for (anon_idx = 0; anon_idx < npages; anon_idx++) {
621 621 if ((sptd->spt_flags & SHM_PAGEABLE) == 0) {
622 622 if ((ap = anon_get_ptr(amp->ahp, anon_idx)) == NULL) {
623 623 panic("segspt_free_pages: null app");
624 624 /*NOTREACHED*/
625 625 }
626 626 } else {
627 627 if ((ap = anon_get_next_ptr(amp->ahp, &anon_idx))
628 628 == NULL)
629 629 continue;
630 630 }
631 631 ASSERT(ANON_ISBUSY(anon_get_slot(amp->ahp, anon_idx)) == 0);
632 632 swap_xlate(ap, &vp, &off);
633 633
634 634 /*
635 635 * If this platform supports HAT_DYNAMIC_ISM_UNMAP,
636 636 * the pages won't be having SE_SHARED lock at this
637 637 * point.
638 638 *
639 639 * On platforms that do not support HAT_DYNAMIC_ISM_UNMAP,
640 640 * the pages are still held SE_SHARED locked from the
641 641 * original segspt_create()
642 642 *
643 643 * Our goal is to get SE_EXCL lock on each page, remove
644 644 * permanent lock on it and invalidate the page.
645 645 */
646 646 if ((sptd->spt_flags & SHM_PAGEABLE) == 0) {
647 647 if (hat_flags == HAT_UNLOAD_UNMAP)
648 648 pp = page_lookup(vp, off, SE_EXCL);
649 649 else {
650 650 if ((pp = page_find(vp, off)) == NULL) {
651 651 panic("segspt_free_pages: "
652 652 "page not locked");
653 653 /*NOTREACHED*/
654 654 }
655 655 if (!page_tryupgrade(pp)) {
656 656 page_unlock(pp);
657 657 pp = page_lookup(vp, off, SE_EXCL);
658 658 }
659 659 }
660 660 if (pp == NULL) {
661 661 panic("segspt_free_pages: "
662 662 "page not in the system");
663 663 /*NOTREACHED*/
664 664 }
665 665 ASSERT(pp->p_lckcnt > 0);
666 666 page_pp_unlock(pp, 0, 1);
667 667 if (pp->p_lckcnt == 0)
668 668 unlocked_bytes += PAGESIZE;
669 669 } else {
670 670 if ((pp = page_lookup(vp, off, SE_EXCL)) == NULL)
671 671 continue;
672 672 }
673 673 /*
674 674 * It's logical to invalidate the pages here as in most cases
675 675 * these were created by segspt.
676 676 */
677 677 if (pp->p_szc != 0) {
678 678 if (root == 0) {
679 679 ASSERT(curnpgs == 0);
680 680 root = 1;
681 681 rootpp = pp;
682 682 pgs = curnpgs = page_get_pagecnt(pp->p_szc);
683 683 ASSERT(pgs > 1);
684 684 ASSERT(IS_P2ALIGNED(pgs, pgs));
685 685 ASSERT(!(page_pptonum(pp) & (pgs - 1)));
686 686 curnpgs--;
687 687 } else if ((page_pptonum(pp) & (pgs - 1)) == pgs - 1) {
688 688 ASSERT(curnpgs == 1);
689 689 ASSERT(page_pptonum(pp) ==
690 690 page_pptonum(rootpp) + (pgs - 1));
691 691 page_destroy_pages(rootpp);
692 692 root = 0;
693 693 curnpgs = 0;
694 694 } else {
695 695 ASSERT(curnpgs > 1);
696 696 ASSERT(page_pptonum(pp) ==
697 697 page_pptonum(rootpp) + (pgs - curnpgs));
698 698 curnpgs--;
699 699 }
700 700 } else {
701 701 if (root != 0 || curnpgs != 0) {
702 702 panic("segspt_free_pages: bad large page");
703 703 /*NOTREACHED*/
704 704 }
705 705 /*
706 706 * Before destroying the pages, we need to take care
707 707 * of the rctl locked memory accounting. For that
708 708 * we need to calculte the unlocked_bytes.
709 709 */
710 710 if (pp->p_lckcnt > 0)
711 711 unlocked_bytes += PAGESIZE;
712 712 /*LINTED: constant in conditional context */
713 713 VN_DISPOSE(pp, B_INVAL, 0, kcred);
714 714 }
715 715 }
716 716 if ((sptd->spt_flags & SHM_PAGEABLE) == 0) {
717 717 if (unlocked_bytes > 0)
718 718 rctl_decr_locked_mem(NULL, proj, unlocked_bytes, 0);
719 719 mutex_exit(&sp->shm_mlock);
720 720 }
721 721 if (root != 0 || curnpgs != 0) {
722 722 panic("segspt_free_pages: bad large page");
723 723 /*NOTREACHED*/
724 724 }
725 725
726 726 /*
727 727 * mark that pages have been released
728 728 */
729 729 sptd->spt_realsize = 0;
730 730
731 731 if ((sptd->spt_flags & SHM_PAGEABLE) == 0) {
732 732 atomic_add_long(&spt_used, -npages);
733 733 anon_swap_restore(npages);
734 734 }
735 735 }
736 736
737 737 /*
738 738 * Get memory allocation policy info for specified address in given segment
739 739 */
740 740 static lgrp_mem_policy_info_t *
741 741 segspt_getpolicy(struct seg *seg, caddr_t addr)
742 742 {
743 743 struct anon_map *amp;
744 744 ulong_t anon_index;
745 745 lgrp_mem_policy_info_t *policy_info;
746 746 struct spt_data *spt_data;
747 747
748 748 ASSERT(seg != NULL);
749 749
750 750 /*
751 751 * Get anon_map from segspt
752 752 *
753 753 * Assume that no lock needs to be held on anon_map, since
754 754 * it should be protected by its reference count which must be
755 755 * nonzero for an existing segment
756 756 * Need to grab readers lock on policy tree though
757 757 */
758 758 spt_data = (struct spt_data *)seg->s_data;
759 759 if (spt_data == NULL)
760 760 return (NULL);
761 761 amp = spt_data->spt_amp;
762 762 ASSERT(amp->refcnt != 0);
763 763
764 764 /*
765 765 * Get policy info
766 766 *
767 767 * Assume starting anon index of 0
768 768 */
769 769 anon_index = seg_page(seg, addr);
770 770 policy_info = lgrp_shm_policy_get(amp, anon_index, NULL, 0);
771 771
772 772 return (policy_info);
773 773 }
774 774
775 775 /*
776 776 * DISM only.
777 777 * Return locked pages over a given range.
778 778 *
779 779 * We will cache all DISM locked pages and save the pplist for the
780 780 * entire segment in the ppa field of the underlying DISM segment structure.
781 781 * Later, during a call to segspt_reclaim() we will use this ppa array
782 782 * to page_unlock() all of the pages and then we will free this ppa list.
783 783 */
784 784 /*ARGSUSED*/
785 785 static int
786 786 segspt_dismpagelock(struct seg *seg, caddr_t addr, size_t len,
787 787 struct page ***ppp, enum lock_type type, enum seg_rw rw)
788 788 {
789 789 struct shm_data *shmd = (struct shm_data *)seg->s_data;
790 790 struct seg *sptseg = shmd->shm_sptseg;
791 791 struct spt_data *sptd = sptseg->s_data;
792 792 pgcnt_t pg_idx, npages, tot_npages, npgs;
793 793 struct page **pplist, **pl, **ppa, *pp;
794 794 struct anon_map *amp;
795 795 spgcnt_t an_idx;
796 796 int ret = ENOTSUP;
797 797 uint_t pl_built = 0;
798 798 struct anon *ap;
799 799 struct vnode *vp;
800 800 u_offset_t off;
801 801 pgcnt_t claim_availrmem = 0;
802 802 uint_t szc;
803 803
804 804 ASSERT(seg->s_as && AS_LOCK_HELD(seg->s_as, &seg->s_as->a_lock));
805 805 ASSERT(type == L_PAGELOCK || type == L_PAGEUNLOCK);
806 806
807 807 /*
808 808 * We want to lock/unlock the entire ISM segment. Therefore,
809 809 * we will be using the underlying sptseg and it's base address
810 810 * and length for the caching arguments.
811 811 */
812 812 ASSERT(sptseg);
813 813 ASSERT(sptd);
814 814
815 815 pg_idx = seg_page(seg, addr);
816 816 npages = btopr(len);
817 817
818 818 /*
819 819 * check if the request is larger than number of pages covered
820 820 * by amp
821 821 */
822 822 if (pg_idx + npages > btopr(sptd->spt_amp->size)) {
823 823 *ppp = NULL;
824 824 return (ENOTSUP);
825 825 }
826 826
827 827 if (type == L_PAGEUNLOCK) {
828 828 ASSERT(sptd->spt_ppa != NULL);
829 829
830 830 seg_pinactive(seg, NULL, seg->s_base, sptd->spt_amp->size,
831 831 sptd->spt_ppa, S_WRITE, SEGP_FORCE_WIRED, segspt_reclaim);
832 832
833 833 /*
834 834 * If someone is blocked while unmapping, we purge
835 835 * segment page cache and thus reclaim pplist synchronously
836 836 * without waiting for seg_pasync_thread. This speeds up
837 837 * unmapping in cases where munmap(2) is called, while
838 838 * raw async i/o is still in progress or where a thread
839 839 * exits on data fault in a multithreaded application.
840 840 */
841 841 if ((sptd->spt_flags & DISM_PPA_CHANGED) ||
842 842 (AS_ISUNMAPWAIT(seg->s_as) &&
843 843 shmd->shm_softlockcnt > 0)) {
844 844 segspt_purge(seg);
845 845 }
846 846 return (0);
847 847 }
848 848
849 849 /* The L_PAGELOCK case ... */
850 850
851 851 if (sptd->spt_flags & DISM_PPA_CHANGED) {
852 852 segspt_purge(seg);
853 853 /*
854 854 * for DISM ppa needs to be rebuild since
855 855 * number of locked pages could be changed
856 856 */
857 857 *ppp = NULL;
858 858 return (ENOTSUP);
859 859 }
860 860
861 861 /*
862 862 * First try to find pages in segment page cache, without
863 863 * holding the segment lock.
864 864 */
865 865 pplist = seg_plookup(seg, NULL, seg->s_base, sptd->spt_amp->size,
866 866 S_WRITE, SEGP_FORCE_WIRED);
867 867 if (pplist != NULL) {
868 868 ASSERT(sptd->spt_ppa != NULL);
869 869 ASSERT(sptd->spt_ppa == pplist);
870 870 ppa = sptd->spt_ppa;
871 871 for (an_idx = pg_idx; an_idx < pg_idx + npages; ) {
872 872 if (ppa[an_idx] == NULL) {
873 873 seg_pinactive(seg, NULL, seg->s_base,
874 874 sptd->spt_amp->size, ppa,
875 875 S_WRITE, SEGP_FORCE_WIRED, segspt_reclaim);
876 876 *ppp = NULL;
877 877 return (ENOTSUP);
878 878 }
879 879 if ((szc = ppa[an_idx]->p_szc) != 0) {
880 880 npgs = page_get_pagecnt(szc);
881 881 an_idx = P2ROUNDUP(an_idx + 1, npgs);
882 882 } else {
883 883 an_idx++;
884 884 }
885 885 }
886 886 /*
887 887 * Since we cache the entire DISM segment, we want to
888 888 * set ppp to point to the first slot that corresponds
889 889 * to the requested addr, i.e. pg_idx.
890 890 */
891 891 *ppp = &(sptd->spt_ppa[pg_idx]);
892 892 return (0);
893 893 }
894 894
895 895 mutex_enter(&sptd->spt_lock);
896 896 /*
897 897 * try to find pages in segment page cache with mutex
898 898 */
899 899 pplist = seg_plookup(seg, NULL, seg->s_base, sptd->spt_amp->size,
900 900 S_WRITE, SEGP_FORCE_WIRED);
901 901 if (pplist != NULL) {
902 902 ASSERT(sptd->spt_ppa != NULL);
903 903 ASSERT(sptd->spt_ppa == pplist);
904 904 ppa = sptd->spt_ppa;
905 905 for (an_idx = pg_idx; an_idx < pg_idx + npages; ) {
906 906 if (ppa[an_idx] == NULL) {
907 907 mutex_exit(&sptd->spt_lock);
908 908 seg_pinactive(seg, NULL, seg->s_base,
909 909 sptd->spt_amp->size, ppa,
910 910 S_WRITE, SEGP_FORCE_WIRED, segspt_reclaim);
911 911 *ppp = NULL;
912 912 return (ENOTSUP);
913 913 }
914 914 if ((szc = ppa[an_idx]->p_szc) != 0) {
915 915 npgs = page_get_pagecnt(szc);
916 916 an_idx = P2ROUNDUP(an_idx + 1, npgs);
917 917 } else {
918 918 an_idx++;
919 919 }
920 920 }
921 921 /*
922 922 * Since we cache the entire DISM segment, we want to
923 923 * set ppp to point to the first slot that corresponds
924 924 * to the requested addr, i.e. pg_idx.
925 925 */
926 926 mutex_exit(&sptd->spt_lock);
927 927 *ppp = &(sptd->spt_ppa[pg_idx]);
928 928 return (0);
929 929 }
930 930 if (seg_pinsert_check(seg, NULL, seg->s_base, sptd->spt_amp->size,
931 931 SEGP_FORCE_WIRED) == SEGP_FAIL) {
932 932 mutex_exit(&sptd->spt_lock);
933 933 *ppp = NULL;
934 934 return (ENOTSUP);
935 935 }
936 936
937 937 /*
938 938 * No need to worry about protections because DISM pages are always rw.
939 939 */
940 940 pl = pplist = NULL;
941 941 amp = sptd->spt_amp;
942 942
943 943 /*
944 944 * Do we need to build the ppa array?
945 945 */
946 946 if (sptd->spt_ppa == NULL) {
947 947 pgcnt_t lpg_cnt = 0;
948 948
949 949 pl_built = 1;
950 950 tot_npages = btopr(sptd->spt_amp->size);
951 951
952 952 ASSERT(sptd->spt_pcachecnt == 0);
953 953 pplist = kmem_zalloc(sizeof (page_t *) * tot_npages, KM_SLEEP);
954 954 pl = pplist;
955 955
956 956 ANON_LOCK_ENTER(&->a_rwlock, RW_WRITER);
957 957 for (an_idx = 0; an_idx < tot_npages; ) {
958 958 ap = anon_get_ptr(amp->ahp, an_idx);
959 959 /*
960 960 * Cache only mlocked pages. For large pages
961 961 * if one (constituent) page is mlocked
962 962 * all pages for that large page
963 963 * are cached also. This is for quick
964 964 * lookups of ppa array;
965 965 */
966 966 if ((ap != NULL) && (lpg_cnt != 0 ||
967 967 (sptd->spt_ppa_lckcnt[an_idx] != 0))) {
968 968
969 969 swap_xlate(ap, &vp, &off);
970 970 pp = page_lookup(vp, off, SE_SHARED);
971 971 ASSERT(pp != NULL);
972 972 if (lpg_cnt == 0) {
973 973 lpg_cnt++;
974 974 /*
975 975 * For a small page, we are done --
976 976 * lpg_count is reset to 0 below.
977 977 *
978 978 * For a large page, we are guaranteed
979 979 * to find the anon structures of all
980 980 * constituent pages and a non-zero
981 981 * lpg_cnt ensures that we don't test
982 982 * for mlock for these. We are done
983 983 * when lpg_count reaches (npgs + 1).
984 984 * If we are not the first constituent
985 985 * page, restart at the first one.
986 986 */
987 987 npgs = page_get_pagecnt(pp->p_szc);
988 988 if (!IS_P2ALIGNED(an_idx, npgs)) {
989 989 an_idx = P2ALIGN(an_idx, npgs);
990 990 page_unlock(pp);
991 991 continue;
992 992 }
993 993 }
994 994 if (++lpg_cnt > npgs)
995 995 lpg_cnt = 0;
996 996
997 997 /*
998 998 * availrmem is decremented only
999 999 * for unlocked pages
1000 1000 */
1001 1001 if (sptd->spt_ppa_lckcnt[an_idx] == 0)
1002 1002 claim_availrmem++;
1003 1003 pplist[an_idx] = pp;
1004 1004 }
1005 1005 an_idx++;
1006 1006 }
1007 1007 ANON_LOCK_EXIT(&->a_rwlock);
1008 1008
1009 1009 if (claim_availrmem) {
1010 1010 mutex_enter(&freemem_lock);
1011 1011 if (availrmem < tune.t_minarmem + claim_availrmem) {
1012 1012 mutex_exit(&freemem_lock);
1013 1013 ret = ENOTSUP;
1014 1014 claim_availrmem = 0;
1015 1015 goto insert_fail;
1016 1016 } else {
1017 1017 availrmem -= claim_availrmem;
1018 1018 }
1019 1019 mutex_exit(&freemem_lock);
1020 1020 }
1021 1021
1022 1022 sptd->spt_ppa = pl;
1023 1023 } else {
1024 1024 /*
1025 1025 * We already have a valid ppa[].
1026 1026 */
1027 1027 pl = sptd->spt_ppa;
1028 1028 }
1029 1029
1030 1030 ASSERT(pl != NULL);
1031 1031
1032 1032 ret = seg_pinsert(seg, NULL, seg->s_base, sptd->spt_amp->size,
1033 1033 sptd->spt_amp->size, pl, S_WRITE, SEGP_FORCE_WIRED,
1034 1034 segspt_reclaim);
1035 1035 if (ret == SEGP_FAIL) {
1036 1036 /*
1037 1037 * seg_pinsert failed. We return
1038 1038 * ENOTSUP, so that the as_pagelock() code will
1039 1039 * then try the slower F_SOFTLOCK path.
1040 1040 */
1041 1041 if (pl_built) {
1042 1042 /*
1043 1043 * No one else has referenced the ppa[].
1044 1044 * We created it and we need to destroy it.
1045 1045 */
1046 1046 sptd->spt_ppa = NULL;
1047 1047 }
1048 1048 ret = ENOTSUP;
1049 1049 goto insert_fail;
1050 1050 }
1051 1051
1052 1052 /*
1053 1053 * In either case, we increment softlockcnt on the 'real' segment.
1054 1054 */
1055 1055 sptd->spt_pcachecnt++;
1056 1056 atomic_inc_ulong((ulong_t *)(&(shmd->shm_softlockcnt)));
1057 1057
1058 1058 ppa = sptd->spt_ppa;
1059 1059 for (an_idx = pg_idx; an_idx < pg_idx + npages; ) {
1060 1060 if (ppa[an_idx] == NULL) {
1061 1061 mutex_exit(&sptd->spt_lock);
1062 1062 seg_pinactive(seg, NULL, seg->s_base,
1063 1063 sptd->spt_amp->size,
1064 1064 pl, S_WRITE, SEGP_FORCE_WIRED, segspt_reclaim);
1065 1065 *ppp = NULL;
1066 1066 return (ENOTSUP);
1067 1067 }
1068 1068 if ((szc = ppa[an_idx]->p_szc) != 0) {
1069 1069 npgs = page_get_pagecnt(szc);
1070 1070 an_idx = P2ROUNDUP(an_idx + 1, npgs);
1071 1071 } else {
1072 1072 an_idx++;
1073 1073 }
1074 1074 }
1075 1075 /*
1076 1076 * We can now drop the sptd->spt_lock since the ppa[]
1077 1077 * exists and he have incremented pacachecnt.
1078 1078 */
1079 1079 mutex_exit(&sptd->spt_lock);
1080 1080
1081 1081 /*
1082 1082 * Since we cache the entire segment, we want to
1083 1083 * set ppp to point to the first slot that corresponds
1084 1084 * to the requested addr, i.e. pg_idx.
1085 1085 */
1086 1086 *ppp = &(sptd->spt_ppa[pg_idx]);
1087 1087 return (0);
1088 1088
1089 1089 insert_fail:
1090 1090 /*
1091 1091 * We will only reach this code if we tried and failed.
1092 1092 *
1093 1093 * And we can drop the lock on the dummy seg, once we've failed
1094 1094 * to set up a new ppa[].
1095 1095 */
1096 1096 mutex_exit(&sptd->spt_lock);
1097 1097
1098 1098 if (pl_built) {
1099 1099 if (claim_availrmem) {
1100 1100 mutex_enter(&freemem_lock);
1101 1101 availrmem += claim_availrmem;
1102 1102 mutex_exit(&freemem_lock);
1103 1103 }
1104 1104
1105 1105 /*
1106 1106 * We created pl and we need to destroy it.
1107 1107 */
1108 1108 pplist = pl;
1109 1109 for (an_idx = 0; an_idx < tot_npages; an_idx++) {
1110 1110 if (pplist[an_idx] != NULL)
1111 1111 page_unlock(pplist[an_idx]);
1112 1112 }
1113 1113 kmem_free(pl, sizeof (page_t *) * tot_npages);
1114 1114 }
1115 1115
1116 1116 if (shmd->shm_softlockcnt <= 0) {
1117 1117 if (AS_ISUNMAPWAIT(seg->s_as)) {
1118 1118 mutex_enter(&seg->s_as->a_contents);
1119 1119 if (AS_ISUNMAPWAIT(seg->s_as)) {
1120 1120 AS_CLRUNMAPWAIT(seg->s_as);
1121 1121 cv_broadcast(&seg->s_as->a_cv);
1122 1122 }
1123 1123 mutex_exit(&seg->s_as->a_contents);
1124 1124 }
1125 1125 }
1126 1126 *ppp = NULL;
1127 1127 return (ret);
1128 1128 }
1129 1129
1130 1130
1131 1131
1132 1132 /*
1133 1133 * return locked pages over a given range.
1134 1134 *
1135 1135 * We will cache the entire ISM segment and save the pplist for the
1136 1136 * entire segment in the ppa field of the underlying ISM segment structure.
1137 1137 * Later, during a call to segspt_reclaim() we will use this ppa array
1138 1138 * to page_unlock() all of the pages and then we will free this ppa list.
1139 1139 */
1140 1140 /*ARGSUSED*/
1141 1141 static int
1142 1142 segspt_shmpagelock(struct seg *seg, caddr_t addr, size_t len,
1143 1143 struct page ***ppp, enum lock_type type, enum seg_rw rw)
1144 1144 {
1145 1145 struct shm_data *shmd = (struct shm_data *)seg->s_data;
1146 1146 struct seg *sptseg = shmd->shm_sptseg;
1147 1147 struct spt_data *sptd = sptseg->s_data;
1148 1148 pgcnt_t np, page_index, npages;
1149 1149 caddr_t a, spt_base;
1150 1150 struct page **pplist, **pl, *pp;
1151 1151 struct anon_map *amp;
1152 1152 ulong_t anon_index;
1153 1153 int ret = ENOTSUP;
1154 1154 uint_t pl_built = 0;
1155 1155 struct anon *ap;
1156 1156 struct vnode *vp;
1157 1157 u_offset_t off;
1158 1158
1159 1159 ASSERT(seg->s_as && AS_LOCK_HELD(seg->s_as, &seg->s_as->a_lock));
1160 1160 ASSERT(type == L_PAGELOCK || type == L_PAGEUNLOCK);
1161 1161
1162 1162
1163 1163 /*
1164 1164 * We want to lock/unlock the entire ISM segment. Therefore,
1165 1165 * we will be using the underlying sptseg and it's base address
1166 1166 * and length for the caching arguments.
1167 1167 */
1168 1168 ASSERT(sptseg);
1169 1169 ASSERT(sptd);
1170 1170
1171 1171 if (sptd->spt_flags & SHM_PAGEABLE) {
1172 1172 return (segspt_dismpagelock(seg, addr, len, ppp, type, rw));
1173 1173 }
1174 1174
1175 1175 page_index = seg_page(seg, addr);
1176 1176 npages = btopr(len);
1177 1177
1178 1178 /*
1179 1179 * check if the request is larger than number of pages covered
1180 1180 * by amp
1181 1181 */
1182 1182 if (page_index + npages > btopr(sptd->spt_amp->size)) {
1183 1183 *ppp = NULL;
1184 1184 return (ENOTSUP);
1185 1185 }
1186 1186
1187 1187 if (type == L_PAGEUNLOCK) {
1188 1188
1189 1189 ASSERT(sptd->spt_ppa != NULL);
1190 1190
1191 1191 seg_pinactive(seg, NULL, seg->s_base, sptd->spt_amp->size,
1192 1192 sptd->spt_ppa, S_WRITE, SEGP_FORCE_WIRED, segspt_reclaim);
1193 1193
1194 1194 /*
1195 1195 * If someone is blocked while unmapping, we purge
1196 1196 * segment page cache and thus reclaim pplist synchronously
1197 1197 * without waiting for seg_pasync_thread. This speeds up
1198 1198 * unmapping in cases where munmap(2) is called, while
1199 1199 * raw async i/o is still in progress or where a thread
1200 1200 * exits on data fault in a multithreaded application.
1201 1201 */
1202 1202 if (AS_ISUNMAPWAIT(seg->s_as) && (shmd->shm_softlockcnt > 0)) {
1203 1203 segspt_purge(seg);
1204 1204 }
1205 1205 return (0);
1206 1206 }
1207 1207
1208 1208 /* The L_PAGELOCK case... */
1209 1209
1210 1210 /*
1211 1211 * First try to find pages in segment page cache, without
1212 1212 * holding the segment lock.
1213 1213 */
1214 1214 pplist = seg_plookup(seg, NULL, seg->s_base, sptd->spt_amp->size,
1215 1215 S_WRITE, SEGP_FORCE_WIRED);
1216 1216 if (pplist != NULL) {
1217 1217 ASSERT(sptd->spt_ppa == pplist);
1218 1218 ASSERT(sptd->spt_ppa[page_index]);
1219 1219 /*
1220 1220 * Since we cache the entire ISM segment, we want to
1221 1221 * set ppp to point to the first slot that corresponds
1222 1222 * to the requested addr, i.e. page_index.
1223 1223 */
1224 1224 *ppp = &(sptd->spt_ppa[page_index]);
1225 1225 return (0);
1226 1226 }
1227 1227
1228 1228 mutex_enter(&sptd->spt_lock);
1229 1229
1230 1230 /*
1231 1231 * try to find pages in segment page cache
1232 1232 */
1233 1233 pplist = seg_plookup(seg, NULL, seg->s_base, sptd->spt_amp->size,
1234 1234 S_WRITE, SEGP_FORCE_WIRED);
1235 1235 if (pplist != NULL) {
1236 1236 ASSERT(sptd->spt_ppa == pplist);
1237 1237 /*
1238 1238 * Since we cache the entire segment, we want to
1239 1239 * set ppp to point to the first slot that corresponds
1240 1240 * to the requested addr, i.e. page_index.
1241 1241 */
1242 1242 mutex_exit(&sptd->spt_lock);
1243 1243 *ppp = &(sptd->spt_ppa[page_index]);
1244 1244 return (0);
1245 1245 }
1246 1246
1247 1247 if (seg_pinsert_check(seg, NULL, seg->s_base, sptd->spt_amp->size,
1248 1248 SEGP_FORCE_WIRED) == SEGP_FAIL) {
1249 1249 mutex_exit(&sptd->spt_lock);
1250 1250 *ppp = NULL;
1251 1251 return (ENOTSUP);
1252 1252 }
1253 1253
1254 1254 /*
1255 1255 * No need to worry about protections because ISM pages
1256 1256 * are always rw.
1257 1257 */
1258 1258 pl = pplist = NULL;
1259 1259
1260 1260 /*
1261 1261 * Do we need to build the ppa array?
1262 1262 */
1263 1263 if (sptd->spt_ppa == NULL) {
1264 1264 ASSERT(sptd->spt_ppa == pplist);
1265 1265
1266 1266 spt_base = sptseg->s_base;
1267 1267 pl_built = 1;
1268 1268
1269 1269 /*
1270 1270 * availrmem is decremented once during anon_swap_adjust()
1271 1271 * and is incremented during the anon_unresv(), which is
1272 1272 * called from shm_rm_amp() when the segment is destroyed.
1273 1273 */
1274 1274 amp = sptd->spt_amp;
1275 1275 ASSERT(amp != NULL);
1276 1276
1277 1277 /* pcachecnt is protected by sptd->spt_lock */
1278 1278 ASSERT(sptd->spt_pcachecnt == 0);
1279 1279 pplist = kmem_zalloc(sizeof (page_t *)
1280 1280 * btopr(sptd->spt_amp->size), KM_SLEEP);
1281 1281 pl = pplist;
1282 1282
1283 1283 anon_index = seg_page(sptseg, spt_base);
1284 1284
1285 1285 ANON_LOCK_ENTER(&->a_rwlock, RW_WRITER);
1286 1286 for (a = spt_base; a < (spt_base + sptd->spt_amp->size);
1287 1287 a += PAGESIZE, anon_index++, pplist++) {
1288 1288 ap = anon_get_ptr(amp->ahp, anon_index);
1289 1289 ASSERT(ap != NULL);
1290 1290 swap_xlate(ap, &vp, &off);
1291 1291 pp = page_lookup(vp, off, SE_SHARED);
1292 1292 ASSERT(pp != NULL);
1293 1293 *pplist = pp;
1294 1294 }
1295 1295 ANON_LOCK_EXIT(&->a_rwlock);
1296 1296
1297 1297 if (a < (spt_base + sptd->spt_amp->size)) {
1298 1298 ret = ENOTSUP;
1299 1299 goto insert_fail;
1300 1300 }
1301 1301 sptd->spt_ppa = pl;
1302 1302 } else {
1303 1303 /*
1304 1304 * We already have a valid ppa[].
1305 1305 */
1306 1306 pl = sptd->spt_ppa;
1307 1307 }
1308 1308
1309 1309 ASSERT(pl != NULL);
1310 1310
1311 1311 ret = seg_pinsert(seg, NULL, seg->s_base, sptd->spt_amp->size,
1312 1312 sptd->spt_amp->size, pl, S_WRITE, SEGP_FORCE_WIRED,
1313 1313 segspt_reclaim);
1314 1314 if (ret == SEGP_FAIL) {
1315 1315 /*
1316 1316 * seg_pinsert failed. We return
1317 1317 * ENOTSUP, so that the as_pagelock() code will
1318 1318 * then try the slower F_SOFTLOCK path.
1319 1319 */
1320 1320 if (pl_built) {
1321 1321 /*
1322 1322 * No one else has referenced the ppa[].
1323 1323 * We created it and we need to destroy it.
1324 1324 */
1325 1325 sptd->spt_ppa = NULL;
1326 1326 }
1327 1327 ret = ENOTSUP;
1328 1328 goto insert_fail;
1329 1329 }
1330 1330
1331 1331 /*
1332 1332 * In either case, we increment softlockcnt on the 'real' segment.
1333 1333 */
1334 1334 sptd->spt_pcachecnt++;
1335 1335 atomic_inc_ulong((ulong_t *)(&(shmd->shm_softlockcnt)));
1336 1336
1337 1337 /*
1338 1338 * We can now drop the sptd->spt_lock since the ppa[]
1339 1339 * exists and he have incremented pacachecnt.
1340 1340 */
1341 1341 mutex_exit(&sptd->spt_lock);
1342 1342
1343 1343 /*
1344 1344 * Since we cache the entire segment, we want to
1345 1345 * set ppp to point to the first slot that corresponds
1346 1346 * to the requested addr, i.e. page_index.
1347 1347 */
1348 1348 *ppp = &(sptd->spt_ppa[page_index]);
1349 1349 return (0);
1350 1350
1351 1351 insert_fail:
1352 1352 /*
1353 1353 * We will only reach this code if we tried and failed.
1354 1354 *
1355 1355 * And we can drop the lock on the dummy seg, once we've failed
1356 1356 * to set up a new ppa[].
1357 1357 */
1358 1358 mutex_exit(&sptd->spt_lock);
1359 1359
1360 1360 if (pl_built) {
1361 1361 /*
1362 1362 * We created pl and we need to destroy it.
1363 1363 */
1364 1364 pplist = pl;
1365 1365 np = (((uintptr_t)(a - spt_base)) >> PAGESHIFT);
1366 1366 while (np) {
1367 1367 page_unlock(*pplist);
1368 1368 np--;
1369 1369 pplist++;
1370 1370 }
1371 1371 kmem_free(pl, sizeof (page_t *) * btopr(sptd->spt_amp->size));
1372 1372 }
1373 1373 if (shmd->shm_softlockcnt <= 0) {
1374 1374 if (AS_ISUNMAPWAIT(seg->s_as)) {
1375 1375 mutex_enter(&seg->s_as->a_contents);
1376 1376 if (AS_ISUNMAPWAIT(seg->s_as)) {
1377 1377 AS_CLRUNMAPWAIT(seg->s_as);
1378 1378 cv_broadcast(&seg->s_as->a_cv);
1379 1379 }
1380 1380 mutex_exit(&seg->s_as->a_contents);
1381 1381 }
1382 1382 }
1383 1383 *ppp = NULL;
1384 1384 return (ret);
1385 1385 }
1386 1386
1387 1387 /*
1388 1388 * purge any cached pages in the I/O page cache
1389 1389 */
1390 1390 static void
1391 1391 segspt_purge(struct seg *seg)
1392 1392 {
1393 1393 seg_ppurge(seg, NULL, SEGP_FORCE_WIRED);
1394 1394 }
1395 1395
1396 1396 static int
1397 1397 segspt_reclaim(void *ptag, caddr_t addr, size_t len, struct page **pplist,
1398 1398 enum seg_rw rw, int async)
1399 1399 {
1400 1400 struct seg *seg = (struct seg *)ptag;
1401 1401 struct shm_data *shmd = (struct shm_data *)seg->s_data;
1402 1402 struct seg *sptseg;
1403 1403 struct spt_data *sptd;
1404 1404 pgcnt_t npages, i, free_availrmem = 0;
1405 1405 int done = 0;
1406 1406
1407 1407 #ifdef lint
1408 1408 addr = addr;
1409 1409 #endif
1410 1410 sptseg = shmd->shm_sptseg;
1411 1411 sptd = sptseg->s_data;
1412 1412 npages = (len >> PAGESHIFT);
1413 1413 ASSERT(npages);
1414 1414 ASSERT(sptd->spt_pcachecnt != 0);
1415 1415 ASSERT(sptd->spt_ppa == pplist);
1416 1416 ASSERT(npages == btopr(sptd->spt_amp->size));
1417 1417 ASSERT(async || AS_LOCK_HELD(seg->s_as, &seg->s_as->a_lock));
1418 1418
1419 1419 /*
1420 1420 * Acquire the lock on the dummy seg and destroy the
1421 1421 * ppa array IF this is the last pcachecnt.
1422 1422 */
1423 1423 mutex_enter(&sptd->spt_lock);
1424 1424 if (--sptd->spt_pcachecnt == 0) {
1425 1425 for (i = 0; i < npages; i++) {
1426 1426 if (pplist[i] == NULL) {
1427 1427 continue;
1428 1428 }
1429 1429 if (rw == S_WRITE) {
1430 1430 hat_setrefmod(pplist[i]);
1431 1431 } else {
1432 1432 hat_setref(pplist[i]);
1433 1433 }
1434 1434 if ((sptd->spt_flags & SHM_PAGEABLE) &&
1435 1435 (sptd->spt_ppa_lckcnt[i] == 0))
1436 1436 free_availrmem++;
1437 1437 page_unlock(pplist[i]);
1438 1438 }
1439 1439 if ((sptd->spt_flags & SHM_PAGEABLE) && free_availrmem) {
1440 1440 mutex_enter(&freemem_lock);
1441 1441 availrmem += free_availrmem;
1442 1442 mutex_exit(&freemem_lock);
1443 1443 }
1444 1444 /*
1445 1445 * Since we want to cach/uncache the entire ISM segment,
1446 1446 * we will track the pplist in a segspt specific field
1447 1447 * ppa, that is initialized at the time we add an entry to
1448 1448 * the cache.
1449 1449 */
1450 1450 ASSERT(sptd->spt_pcachecnt == 0);
1451 1451 kmem_free(pplist, sizeof (page_t *) * npages);
1452 1452 sptd->spt_ppa = NULL;
1453 1453 sptd->spt_flags &= ~DISM_PPA_CHANGED;
1454 1454 sptd->spt_gen++;
1455 1455 cv_broadcast(&sptd->spt_cv);
1456 1456 done = 1;
1457 1457 }
1458 1458 mutex_exit(&sptd->spt_lock);
1459 1459
1460 1460 /*
1461 1461 * If we are pcache async thread or called via seg_ppurge_wiredpp() we
1462 1462 * may not hold AS lock (in this case async argument is not 0). This
1463 1463 * means if softlockcnt drops to 0 after the decrement below address
1464 1464 * space may get freed. We can't allow it since after softlock
1465 1465 * derement to 0 we still need to access as structure for possible
1466 1466 * wakeup of unmap waiters. To prevent the disappearance of as we take
1467 1467 * this segment's shm_segfree_syncmtx. segspt_shmfree() also takes
1468 1468 * this mutex as a barrier to make sure this routine completes before
1469 1469 * segment is freed.
1470 1470 *
1471 1471 * The second complication we have to deal with in async case is a
1472 1472 * possibility of missed wake up of unmap wait thread. When we don't
1473 1473 * hold as lock here we may take a_contents lock before unmap wait
1474 1474 * thread that was first to see softlockcnt was still not 0. As a
1475 1475 * result we'll fail to wake up an unmap wait thread. To avoid this
1476 1476 * race we set nounmapwait flag in as structure if we drop softlockcnt
1477 1477 * to 0 if async is not 0. unmapwait thread
1478 1478 * will not block if this flag is set.
1479 1479 */
1480 1480 if (async)
1481 1481 mutex_enter(&shmd->shm_segfree_syncmtx);
1482 1482
1483 1483 /*
1484 1484 * Now decrement softlockcnt.
1485 1485 */
1486 1486 ASSERT(shmd->shm_softlockcnt > 0);
1487 1487 atomic_dec_ulong((ulong_t *)(&(shmd->shm_softlockcnt)));
1488 1488
1489 1489 if (shmd->shm_softlockcnt <= 0) {
1490 1490 if (async || AS_ISUNMAPWAIT(seg->s_as)) {
1491 1491 mutex_enter(&seg->s_as->a_contents);
1492 1492 if (async)
1493 1493 AS_SETNOUNMAPWAIT(seg->s_as);
1494 1494 if (AS_ISUNMAPWAIT(seg->s_as)) {
1495 1495 AS_CLRUNMAPWAIT(seg->s_as);
1496 1496 cv_broadcast(&seg->s_as->a_cv);
1497 1497 }
1498 1498 mutex_exit(&seg->s_as->a_contents);
1499 1499 }
1500 1500 }
1501 1501
1502 1502 if (async)
1503 1503 mutex_exit(&shmd->shm_segfree_syncmtx);
1504 1504
1505 1505 return (done);
1506 1506 }
1507 1507
1508 1508 /*
1509 1509 * Do a F_SOFTUNLOCK call over the range requested.
1510 1510 * The range must have already been F_SOFTLOCK'ed.
1511 1511 *
1512 1512 * The calls to acquire and release the anon map lock mutex were
1513 1513 * removed in order to avoid a deadly embrace during a DR
1514 1514 * memory delete operation. (Eg. DR blocks while waiting for a
1515 1515 * exclusive lock on a page that is being used for kaio; the
1516 1516 * thread that will complete the kaio and call segspt_softunlock
1517 1517 * blocks on the anon map lock; another thread holding the anon
1518 1518 * map lock blocks on another page lock via the segspt_shmfault
1519 1519 * -> page_lookup -> page_lookup_create -> page_lock_es code flow.)
1520 1520 *
1521 1521 * The appropriateness of the removal is based upon the following:
1522 1522 * 1. If we are holding a segment's reader lock and the page is held
1523 1523 * shared, then the corresponding element in anonmap which points to
1524 1524 * anon struct cannot change and there is no need to acquire the
1525 1525 * anonymous map lock.
1526 1526 * 2. Threads in segspt_softunlock have a reader lock on the segment
1527 1527 * and already have the shared page lock, so we are guaranteed that
1528 1528 * the anon map slot cannot change and therefore can call anon_get_ptr()
1529 1529 * without grabbing the anonymous map lock.
1530 1530 * 3. Threads that softlock a shared page break copy-on-write, even if
1531 1531 * its a read. Thus cow faults can be ignored with respect to soft
1532 1532 * unlocking, since the breaking of cow means that the anon slot(s) will
1533 1533 * not be shared.
1534 1534 */
1535 1535 static void
1536 1536 segspt_softunlock(struct seg *seg, caddr_t sptseg_addr,
1537 1537 size_t len, enum seg_rw rw)
1538 1538 {
1539 1539 struct shm_data *shmd = (struct shm_data *)seg->s_data;
1540 1540 struct seg *sptseg;
1541 1541 struct spt_data *sptd;
1542 1542 page_t *pp;
1543 1543 caddr_t adr;
1544 1544 struct vnode *vp;
1545 1545 u_offset_t offset;
1546 1546 ulong_t anon_index;
1547 1547 struct anon_map *amp; /* XXX - for locknest */
1548 1548 struct anon *ap = NULL;
1549 1549 pgcnt_t npages;
1550 1550
1551 1551 ASSERT(seg->s_as && AS_LOCK_HELD(seg->s_as, &seg->s_as->a_lock));
1552 1552
1553 1553 sptseg = shmd->shm_sptseg;
1554 1554 sptd = sptseg->s_data;
1555 1555
1556 1556 /*
1557 1557 * Some platforms assume that ISM mappings are HAT_LOAD_LOCK
1558 1558 * and therefore their pages are SE_SHARED locked
1559 1559 * for the entire life of the segment.
1560 1560 */
1561 1561 if ((!hat_supported(HAT_DYNAMIC_ISM_UNMAP, (void *)0)) &&
1562 1562 ((sptd->spt_flags & SHM_PAGEABLE) == 0)) {
1563 1563 goto softlock_decrement;
1564 1564 }
1565 1565
1566 1566 /*
1567 1567 * Any thread is free to do a page_find and
1568 1568 * page_unlock() on the pages within this seg.
1569 1569 *
1570 1570 * We are already holding the as->a_lock on the user's
1571 1571 * real segment, but we need to hold the a_lock on the
1572 1572 * underlying dummy as. This is mostly to satisfy the
1573 1573 * underlying HAT layer.
1574 1574 */
1575 1575 AS_LOCK_ENTER(sptseg->s_as, &sptseg->s_as->a_lock, RW_READER);
1576 1576 hat_unlock(sptseg->s_as->a_hat, sptseg_addr, len);
1577 1577 AS_LOCK_EXIT(sptseg->s_as, &sptseg->s_as->a_lock);
1578 1578
1579 1579 amp = sptd->spt_amp;
1580 1580 ASSERT(amp != NULL);
1581 1581 anon_index = seg_page(sptseg, sptseg_addr);
1582 1582
1583 1583 for (adr = sptseg_addr; adr < sptseg_addr + len; adr += PAGESIZE) {
1584 1584 ap = anon_get_ptr(amp->ahp, anon_index++);
1585 1585 ASSERT(ap != NULL);
1586 1586 swap_xlate(ap, &vp, &offset);
1587 1587
1588 1588 /*
1589 1589 * Use page_find() instead of page_lookup() to
1590 1590 * find the page since we know that it has a
1591 1591 * "shared" lock.
1592 1592 */
1593 1593 pp = page_find(vp, offset);
1594 1594 ASSERT(ap == anon_get_ptr(amp->ahp, anon_index - 1));
1595 1595 if (pp == NULL) {
1596 1596 panic("segspt_softunlock: "
1597 1597 "addr %p, ap %p, vp %p, off %llx",
1598 1598 (void *)adr, (void *)ap, (void *)vp, offset);
1599 1599 /*NOTREACHED*/
1600 1600 }
1601 1601
1602 1602 if (rw == S_WRITE) {
1603 1603 hat_setrefmod(pp);
1604 1604 } else if (rw != S_OTHER) {
1605 1605 hat_setref(pp);
1606 1606 }
1607 1607 page_unlock(pp);
1608 1608 }
1609 1609
1610 1610 softlock_decrement:
1611 1611 npages = btopr(len);
1612 1612 ASSERT(shmd->shm_softlockcnt >= npages);
1613 1613 atomic_add_long((ulong_t *)(&(shmd->shm_softlockcnt)), -npages);
1614 1614 if (shmd->shm_softlockcnt == 0) {
1615 1615 /*
1616 1616 * All SOFTLOCKS are gone. Wakeup any waiting
1617 1617 * unmappers so they can try again to unmap.
1618 1618 * Check for waiters first without the mutex
1619 1619 * held so we don't always grab the mutex on
1620 1620 * softunlocks.
1621 1621 */
1622 1622 if (AS_ISUNMAPWAIT(seg->s_as)) {
1623 1623 mutex_enter(&seg->s_as->a_contents);
1624 1624 if (AS_ISUNMAPWAIT(seg->s_as)) {
1625 1625 AS_CLRUNMAPWAIT(seg->s_as);
1626 1626 cv_broadcast(&seg->s_as->a_cv);
1627 1627 }
1628 1628 mutex_exit(&seg->s_as->a_contents);
1629 1629 }
1630 1630 }
1631 1631 }
1632 1632
1633 1633 int
1634 1634 segspt_shmattach(struct seg *seg, caddr_t *argsp)
1635 1635 {
1636 1636 struct shm_data *shmd_arg = (struct shm_data *)argsp;
1637 1637 struct shm_data *shmd;
1638 1638 struct anon_map *shm_amp = shmd_arg->shm_amp;
1639 1639 struct spt_data *sptd;
1640 1640 int error = 0;
1641 1641
1642 1642 ASSERT(seg->s_as && AS_WRITE_HELD(seg->s_as, &seg->s_as->a_lock));
1643 1643
1644 1644 shmd = kmem_zalloc((sizeof (*shmd)), KM_NOSLEEP);
1645 1645 if (shmd == NULL)
1646 1646 return (ENOMEM);
1647 1647
1648 1648 shmd->shm_sptas = shmd_arg->shm_sptas;
1649 1649 shmd->shm_amp = shm_amp;
1650 1650 shmd->shm_sptseg = shmd_arg->shm_sptseg;
1651 1651
1652 1652 (void) lgrp_shm_policy_set(LGRP_MEM_POLICY_DEFAULT, shm_amp, 0,
1653 1653 NULL, 0, seg->s_size);
1654 1654
1655 1655 mutex_init(&shmd->shm_segfree_syncmtx, NULL, MUTEX_DEFAULT, NULL);
1656 1656
1657 1657 seg->s_data = (void *)shmd;
1658 1658 seg->s_ops = &segspt_shmops;
1659 1659 seg->s_szc = shmd->shm_sptseg->s_szc;
1660 1660 sptd = shmd->shm_sptseg->s_data;
1661 1661
1662 1662 if (sptd->spt_flags & SHM_PAGEABLE) {
1663 1663 if ((shmd->shm_vpage = kmem_zalloc(btopr(shm_amp->size),
1664 1664 KM_NOSLEEP)) == NULL) {
1665 1665 seg->s_data = (void *)NULL;
1666 1666 kmem_free(shmd, (sizeof (*shmd)));
1667 1667 return (ENOMEM);
1668 1668 }
1669 1669 shmd->shm_lckpgs = 0;
1670 1670 if (hat_supported(HAT_DYNAMIC_ISM_UNMAP, (void *)0)) {
1671 1671 if ((error = hat_share(seg->s_as->a_hat, seg->s_base,
1672 1672 shmd_arg->shm_sptas->a_hat, SEGSPTADDR,
1673 1673 seg->s_size, seg->s_szc)) != 0) {
1674 1674 kmem_free(shmd->shm_vpage,
1675 1675 btopr(shm_amp->size));
1676 1676 }
1677 1677 }
1678 1678 } else {
1679 1679 error = hat_share(seg->s_as->a_hat, seg->s_base,
1680 1680 shmd_arg->shm_sptas->a_hat, SEGSPTADDR,
1681 1681 seg->s_size, seg->s_szc);
1682 1682 }
1683 1683 if (error) {
1684 1684 seg->s_szc = 0;
1685 1685 seg->s_data = (void *)NULL;
1686 1686 kmem_free(shmd, (sizeof (*shmd)));
1687 1687 } else {
1688 1688 ANON_LOCK_ENTER(&shm_amp->a_rwlock, RW_WRITER);
1689 1689 shm_amp->refcnt++;
1690 1690 ANON_LOCK_EXIT(&shm_amp->a_rwlock);
1691 1691 }
1692 1692 return (error);
1693 1693 }
1694 1694
1695 1695 int
1696 1696 segspt_shmunmap(struct seg *seg, caddr_t raddr, size_t ssize)
1697 1697 {
1698 1698 struct shm_data *shmd = (struct shm_data *)seg->s_data;
1699 1699 int reclaim = 1;
1700 1700
1701 1701 ASSERT(seg->s_as && AS_WRITE_HELD(seg->s_as, &seg->s_as->a_lock));
1702 1702 retry:
1703 1703 if (shmd->shm_softlockcnt > 0) {
1704 1704 if (reclaim == 1) {
1705 1705 segspt_purge(seg);
1706 1706 reclaim = 0;
1707 1707 goto retry;
1708 1708 }
1709 1709 return (EAGAIN);
1710 1710 }
1711 1711
1712 1712 if (ssize != seg->s_size) {
1713 1713 #ifdef DEBUG
1714 1714 cmn_err(CE_WARN, "Incompatible ssize %lx s_size %lx\n",
1715 1715 ssize, seg->s_size);
1716 1716 #endif
1717 1717 return (EINVAL);
1718 1718 }
1719 1719
1720 1720 (void) segspt_shmlockop(seg, raddr, shmd->shm_amp->size, 0, MC_UNLOCK,
1721 1721 NULL, 0);
1722 1722 hat_unshare(seg->s_as->a_hat, raddr, ssize, seg->s_szc);
1723 1723
1724 1724 seg_free(seg);
1725 1725
1726 1726 return (0);
1727 1727 }
1728 1728
1729 1729 void
1730 1730 segspt_shmfree(struct seg *seg)
1731 1731 {
1732 1732 struct shm_data *shmd = (struct shm_data *)seg->s_data;
1733 1733 struct anon_map *shm_amp = shmd->shm_amp;
1734 1734
1735 1735 ASSERT(seg->s_as && AS_WRITE_HELD(seg->s_as, &seg->s_as->a_lock));
1736 1736
1737 1737 (void) segspt_shmlockop(seg, seg->s_base, shm_amp->size, 0,
1738 1738 MC_UNLOCK, NULL, 0);
1739 1739
1740 1740 /*
1741 1741 * Need to increment refcnt when attaching
1742 1742 * and decrement when detaching because of dup().
1743 1743 */
1744 1744 ANON_LOCK_ENTER(&shm_amp->a_rwlock, RW_WRITER);
1745 1745 shm_amp->refcnt--;
1746 1746 ANON_LOCK_EXIT(&shm_amp->a_rwlock);
1747 1747
1748 1748 if (shmd->shm_vpage) { /* only for DISM */
1749 1749 kmem_free(shmd->shm_vpage, btopr(shm_amp->size));
1750 1750 shmd->shm_vpage = NULL;
1751 1751 }
1752 1752
1753 1753 /*
1754 1754 * Take shm_segfree_syncmtx lock to let segspt_reclaim() finish if it's
1755 1755 * still working with this segment without holding as lock.
1756 1756 */
1757 1757 ASSERT(shmd->shm_softlockcnt == 0);
1758 1758 mutex_enter(&shmd->shm_segfree_syncmtx);
1759 1759 mutex_destroy(&shmd->shm_segfree_syncmtx);
1760 1760
1761 1761 kmem_free(shmd, sizeof (*shmd));
1762 1762 }
1763 1763
1764 1764 /*ARGSUSED*/
1765 1765 int
1766 1766 segspt_shmsetprot(struct seg *seg, caddr_t addr, size_t len, uint_t prot)
1767 1767 {
1768 1768 ASSERT(seg->s_as && AS_LOCK_HELD(seg->s_as, &seg->s_as->a_lock));
1769 1769
1770 1770 /*
1771 1771 * Shared page table is more than shared mapping.
1772 1772 * Individual process sharing page tables can't change prot
1773 1773 * because there is only one set of page tables.
1774 1774 * This will be allowed after private page table is
1775 1775 * supported.
1776 1776 */
1777 1777 /* need to return correct status error? */
1778 1778 return (0);
1779 1779 }
1780 1780
1781 1781
1782 1782 faultcode_t
1783 1783 segspt_dismfault(struct hat *hat, struct seg *seg, caddr_t addr,
1784 1784 size_t len, enum fault_type type, enum seg_rw rw)
1785 1785 {
1786 1786 struct shm_data *shmd = (struct shm_data *)seg->s_data;
1787 1787 struct seg *sptseg = shmd->shm_sptseg;
1788 1788 struct as *curspt = shmd->shm_sptas;
1789 1789 struct spt_data *sptd = sptseg->s_data;
1790 1790 pgcnt_t npages;
1791 1791 size_t size;
1792 1792 caddr_t segspt_addr, shm_addr;
1793 1793 page_t **ppa;
1794 1794 int i;
1795 1795 ulong_t an_idx = 0;
1796 1796 int err = 0;
1797 1797 int dyn_ism_unmap = hat_supported(HAT_DYNAMIC_ISM_UNMAP, (void *)0);
1798 1798 size_t pgsz;
1799 1799 pgcnt_t pgcnt;
1800 1800 caddr_t a;
1801 1801 pgcnt_t pidx;
1802 1802
1803 1803 #ifdef lint
1804 1804 hat = hat;
1805 1805 #endif
1806 1806 ASSERT(seg->s_as && AS_LOCK_HELD(seg->s_as, &seg->s_as->a_lock));
1807 1807
1808 1808 /*
1809 1809 * Because of the way spt is implemented
1810 1810 * the realsize of the segment does not have to be
1811 1811 * equal to the segment size itself. The segment size is
1812 1812 * often in multiples of a page size larger than PAGESIZE.
1813 1813 * The realsize is rounded up to the nearest PAGESIZE
1814 1814 * based on what the user requested. This is a bit of
1815 1815 * ungliness that is historical but not easily fixed
1816 1816 * without re-designing the higher levels of ISM.
1817 1817 */
1818 1818 ASSERT(addr >= seg->s_base);
1819 1819 if (((addr + len) - seg->s_base) > sptd->spt_realsize)
1820 1820 return (FC_NOMAP);
1821 1821 /*
1822 1822 * For all of the following cases except F_PROT, we need to
1823 1823 * make any necessary adjustments to addr and len
1824 1824 * and get all of the necessary page_t's into an array called ppa[].
1825 1825 *
1826 1826 * The code in shmat() forces base addr and len of ISM segment
1827 1827 * to be aligned to largest page size supported. Therefore,
1828 1828 * we are able to handle F_SOFTLOCK and F_INVAL calls in "large
1829 1829 * pagesize" chunks. We want to make sure that we HAT_LOAD_LOCK
1830 1830 * in large pagesize chunks, or else we will screw up the HAT
1831 1831 * layer by calling hat_memload_array() with differing page sizes
1832 1832 * over a given virtual range.
1833 1833 */
1834 1834 pgsz = page_get_pagesize(sptseg->s_szc);
1835 1835 pgcnt = page_get_pagecnt(sptseg->s_szc);
1836 1836 shm_addr = (caddr_t)P2ALIGN((uintptr_t)(addr), pgsz);
1837 1837 size = P2ROUNDUP((uintptr_t)(((addr + len) - shm_addr)), pgsz);
1838 1838 npages = btopr(size);
1839 1839
1840 1840 /*
1841 1841 * Now we need to convert from addr in segshm to addr in segspt.
1842 1842 */
1843 1843 an_idx = seg_page(seg, shm_addr);
1844 1844 segspt_addr = sptseg->s_base + ptob(an_idx);
1845 1845
1846 1846 ASSERT((segspt_addr + ptob(npages)) <=
1847 1847 (sptseg->s_base + sptd->spt_realsize));
1848 1848 ASSERT(segspt_addr < (sptseg->s_base + sptseg->s_size));
1849 1849
1850 1850 switch (type) {
1851 1851
1852 1852 case F_SOFTLOCK:
1853 1853
1854 1854 atomic_add_long((ulong_t *)(&(shmd->shm_softlockcnt)), npages);
1855 1855 /*
1856 1856 * Fall through to the F_INVAL case to load up the hat layer
1857 1857 * entries with the HAT_LOAD_LOCK flag.
1858 1858 */
1859 1859 /* FALLTHRU */
1860 1860 case F_INVAL:
1861 1861
1862 1862 if ((rw == S_EXEC) && !(sptd->spt_prot & PROT_EXEC))
1863 1863 return (FC_NOMAP);
1864 1864
1865 1865 ppa = kmem_zalloc(npages * sizeof (page_t *), KM_SLEEP);
1866 1866
1867 1867 err = spt_anon_getpages(sptseg, segspt_addr, size, ppa);
1868 1868 if (err != 0) {
1869 1869 if (type == F_SOFTLOCK) {
1870 1870 atomic_add_long((ulong_t *)(
1871 1871 &(shmd->shm_softlockcnt)), -npages);
1872 1872 }
1873 1873 goto dism_err;
1874 1874 }
1875 1875 AS_LOCK_ENTER(sptseg->s_as, &sptseg->s_as->a_lock, RW_READER);
1876 1876 a = segspt_addr;
1877 1877 pidx = 0;
1878 1878 if (type == F_SOFTLOCK) {
1879 1879
1880 1880 /*
1881 1881 * Load up the translation keeping it
1882 1882 * locked and don't unlock the page.
1883 1883 */
1884 1884 for (; pidx < npages; a += pgsz, pidx += pgcnt) {
1885 1885 hat_memload_array(sptseg->s_as->a_hat,
1886 1886 a, pgsz, &ppa[pidx], sptd->spt_prot,
1887 1887 HAT_LOAD_LOCK | HAT_LOAD_SHARE);
1888 1888 }
1889 1889 } else {
1890 1890 /*
1891 1891 * Migrate pages marked for migration
1892 1892 */
1893 1893 if (lgrp_optimizations())
1894 1894 page_migrate(seg, shm_addr, ppa, npages);
1895 1895
1896 1896 for (; pidx < npages; a += pgsz, pidx += pgcnt) {
1897 1897 hat_memload_array(sptseg->s_as->a_hat,
1898 1898 a, pgsz, &ppa[pidx],
1899 1899 sptd->spt_prot,
1900 1900 HAT_LOAD_SHARE);
1901 1901 }
1902 1902
1903 1903 /*
1904 1904 * And now drop the SE_SHARED lock(s).
1905 1905 */
1906 1906 if (dyn_ism_unmap) {
1907 1907 for (i = 0; i < npages; i++) {
1908 1908 page_unlock(ppa[i]);
1909 1909 }
1910 1910 }
1911 1911 }
1912 1912
1913 1913 if (!dyn_ism_unmap) {
1914 1914 if (hat_share(seg->s_as->a_hat, shm_addr,
1915 1915 curspt->a_hat, segspt_addr, ptob(npages),
1916 1916 seg->s_szc) != 0) {
1917 1917 panic("hat_share err in DISM fault");
1918 1918 /* NOTREACHED */
1919 1919 }
1920 1920 if (type == F_INVAL) {
1921 1921 for (i = 0; i < npages; i++) {
1922 1922 page_unlock(ppa[i]);
1923 1923 }
1924 1924 }
1925 1925 }
1926 1926 AS_LOCK_EXIT(sptseg->s_as, &sptseg->s_as->a_lock);
1927 1927 dism_err:
1928 1928 kmem_free(ppa, npages * sizeof (page_t *));
1929 1929 return (err);
1930 1930
1931 1931 case F_SOFTUNLOCK:
1932 1932
1933 1933 /*
1934 1934 * This is a bit ugly, we pass in the real seg pointer,
1935 1935 * but the segspt_addr is the virtual address within the
1936 1936 * dummy seg.
1937 1937 */
1938 1938 segspt_softunlock(seg, segspt_addr, size, rw);
1939 1939 return (0);
1940 1940
1941 1941 case F_PROT:
1942 1942
1943 1943 /*
1944 1944 * This takes care of the unusual case where a user
1945 1945 * allocates a stack in shared memory and a register
1946 1946 * window overflow is written to that stack page before
1947 1947 * it is otherwise modified.
1948 1948 *
1949 1949 * We can get away with this because ISM segments are
1950 1950 * always rw. Other than this unusual case, there
1951 1951 * should be no instances of protection violations.
1952 1952 */
1953 1953 return (0);
1954 1954
1955 1955 default:
1956 1956 #ifdef DEBUG
1957 1957 panic("segspt_dismfault default type?");
1958 1958 #else
1959 1959 return (FC_NOMAP);
1960 1960 #endif
1961 1961 }
1962 1962 }
1963 1963
1964 1964
1965 1965 faultcode_t
1966 1966 segspt_shmfault(struct hat *hat, struct seg *seg, caddr_t addr,
1967 1967 size_t len, enum fault_type type, enum seg_rw rw)
1968 1968 {
1969 1969 struct shm_data *shmd = (struct shm_data *)seg->s_data;
1970 1970 struct seg *sptseg = shmd->shm_sptseg;
1971 1971 struct as *curspt = shmd->shm_sptas;
1972 1972 struct spt_data *sptd = sptseg->s_data;
1973 1973 pgcnt_t npages;
1974 1974 size_t size;
1975 1975 caddr_t sptseg_addr, shm_addr;
1976 1976 page_t *pp, **ppa;
1977 1977 int i;
1978 1978 u_offset_t offset;
1979 1979 ulong_t anon_index = 0;
1980 1980 struct vnode *vp;
1981 1981 struct anon_map *amp; /* XXX - for locknest */
1982 1982 struct anon *ap = NULL;
1983 1983 size_t pgsz;
1984 1984 pgcnt_t pgcnt;
1985 1985 caddr_t a;
1986 1986 pgcnt_t pidx;
1987 1987 size_t sz;
1988 1988
1989 1989 #ifdef lint
1990 1990 hat = hat;
1991 1991 #endif
1992 1992
1993 1993 ASSERT(seg->s_as && AS_LOCK_HELD(seg->s_as, &seg->s_as->a_lock));
1994 1994
1995 1995 if (sptd->spt_flags & SHM_PAGEABLE) {
1996 1996 return (segspt_dismfault(hat, seg, addr, len, type, rw));
1997 1997 }
1998 1998
1999 1999 /*
2000 2000 * Because of the way spt is implemented
2001 2001 * the realsize of the segment does not have to be
2002 2002 * equal to the segment size itself. The segment size is
2003 2003 * often in multiples of a page size larger than PAGESIZE.
2004 2004 * The realsize is rounded up to the nearest PAGESIZE
2005 2005 * based on what the user requested. This is a bit of
2006 2006 * ungliness that is historical but not easily fixed
2007 2007 * without re-designing the higher levels of ISM.
2008 2008 */
2009 2009 ASSERT(addr >= seg->s_base);
2010 2010 if (((addr + len) - seg->s_base) > sptd->spt_realsize)
2011 2011 return (FC_NOMAP);
2012 2012 /*
2013 2013 * For all of the following cases except F_PROT, we need to
2014 2014 * make any necessary adjustments to addr and len
2015 2015 * and get all of the necessary page_t's into an array called ppa[].
2016 2016 *
2017 2017 * The code in shmat() forces base addr and len of ISM segment
2018 2018 * to be aligned to largest page size supported. Therefore,
2019 2019 * we are able to handle F_SOFTLOCK and F_INVAL calls in "large
2020 2020 * pagesize" chunks. We want to make sure that we HAT_LOAD_LOCK
2021 2021 * in large pagesize chunks, or else we will screw up the HAT
2022 2022 * layer by calling hat_memload_array() with differing page sizes
2023 2023 * over a given virtual range.
2024 2024 */
2025 2025 pgsz = page_get_pagesize(sptseg->s_szc);
2026 2026 pgcnt = page_get_pagecnt(sptseg->s_szc);
2027 2027 shm_addr = (caddr_t)P2ALIGN((uintptr_t)(addr), pgsz);
2028 2028 size = P2ROUNDUP((uintptr_t)(((addr + len) - shm_addr)), pgsz);
2029 2029 npages = btopr(size);
2030 2030
2031 2031 /*
2032 2032 * Now we need to convert from addr in segshm to addr in segspt.
2033 2033 */
2034 2034 anon_index = seg_page(seg, shm_addr);
2035 2035 sptseg_addr = sptseg->s_base + ptob(anon_index);
2036 2036
2037 2037 /*
2038 2038 * And now we may have to adjust npages downward if we have
2039 2039 * exceeded the realsize of the segment or initial anon
2040 2040 * allocations.
2041 2041 */
2042 2042 if ((sptseg_addr + ptob(npages)) >
2043 2043 (sptseg->s_base + sptd->spt_realsize))
2044 2044 size = (sptseg->s_base + sptd->spt_realsize) - sptseg_addr;
2045 2045
2046 2046 npages = btopr(size);
2047 2047
2048 2048 ASSERT(sptseg_addr < (sptseg->s_base + sptseg->s_size));
2049 2049 ASSERT((sptd->spt_flags & SHM_PAGEABLE) == 0);
2050 2050
2051 2051 switch (type) {
2052 2052
2053 2053 case F_SOFTLOCK:
2054 2054
2055 2055 /*
2056 2056 * availrmem is decremented once during anon_swap_adjust()
2057 2057 * and is incremented during the anon_unresv(), which is
2058 2058 * called from shm_rm_amp() when the segment is destroyed.
2059 2059 */
2060 2060 atomic_add_long((ulong_t *)(&(shmd->shm_softlockcnt)), npages);
2061 2061 /*
2062 2062 * Some platforms assume that ISM pages are SE_SHARED
2063 2063 * locked for the entire life of the segment.
2064 2064 */
2065 2065 if (!hat_supported(HAT_DYNAMIC_ISM_UNMAP, (void *)0))
2066 2066 return (0);
2067 2067 /*
2068 2068 * Fall through to the F_INVAL case to load up the hat layer
2069 2069 * entries with the HAT_LOAD_LOCK flag.
2070 2070 */
2071 2071
2072 2072 /* FALLTHRU */
2073 2073 case F_INVAL:
2074 2074
2075 2075 if ((rw == S_EXEC) && !(sptd->spt_prot & PROT_EXEC))
2076 2076 return (FC_NOMAP);
2077 2077
2078 2078 /*
2079 2079 * Some platforms that do NOT support DYNAMIC_ISM_UNMAP
2080 2080 * may still rely on this call to hat_share(). That
2081 2081 * would imply that those hat's can fault on a
2082 2082 * HAT_LOAD_LOCK translation, which would seem
2083 2083 * contradictory.
2084 2084 */
2085 2085 if (!hat_supported(HAT_DYNAMIC_ISM_UNMAP, (void *)0)) {
2086 2086 if (hat_share(seg->s_as->a_hat, seg->s_base,
2087 2087 curspt->a_hat, sptseg->s_base,
2088 2088 sptseg->s_size, sptseg->s_szc) != 0) {
2089 2089 panic("hat_share error in ISM fault");
2090 2090 /*NOTREACHED*/
2091 2091 }
2092 2092 return (0);
2093 2093 }
2094 2094 ppa = kmem_zalloc(sizeof (page_t *) * npages, KM_SLEEP);
2095 2095
2096 2096 /*
2097 2097 * I see no need to lock the real seg,
2098 2098 * here, because all of our work will be on the underlying
2099 2099 * dummy seg.
2100 2100 *
2101 2101 * sptseg_addr and npages now account for large pages.
2102 2102 */
2103 2103 amp = sptd->spt_amp;
2104 2104 ASSERT(amp != NULL);
2105 2105 anon_index = seg_page(sptseg, sptseg_addr);
2106 2106
2107 2107 ANON_LOCK_ENTER(&->a_rwlock, RW_READER);
2108 2108 for (i = 0; i < npages; i++) {
2109 2109 ap = anon_get_ptr(amp->ahp, anon_index++);
2110 2110 ASSERT(ap != NULL);
2111 2111 swap_xlate(ap, &vp, &offset);
2112 2112 pp = page_lookup(vp, offset, SE_SHARED);
2113 2113 ASSERT(pp != NULL);
2114 2114 ppa[i] = pp;
2115 2115 }
2116 2116 ANON_LOCK_EXIT(&->a_rwlock);
2117 2117 ASSERT(i == npages);
2118 2118
2119 2119 /*
2120 2120 * We are already holding the as->a_lock on the user's
2121 2121 * real segment, but we need to hold the a_lock on the
2122 2122 * underlying dummy as. This is mostly to satisfy the
2123 2123 * underlying HAT layer.
2124 2124 */
2125 2125 AS_LOCK_ENTER(sptseg->s_as, &sptseg->s_as->a_lock, RW_READER);
2126 2126 a = sptseg_addr;
2127 2127 pidx = 0;
2128 2128 if (type == F_SOFTLOCK) {
2129 2129 /*
2130 2130 * Load up the translation keeping it
2131 2131 * locked and don't unlock the page.
2132 2132 */
2133 2133 for (; pidx < npages; a += pgsz, pidx += pgcnt) {
2134 2134 sz = MIN(pgsz, ptob(npages - pidx));
2135 2135 hat_memload_array(sptseg->s_as->a_hat, a,
2136 2136 sz, &ppa[pidx], sptd->spt_prot,
2137 2137 HAT_LOAD_LOCK | HAT_LOAD_SHARE);
2138 2138 }
2139 2139 } else {
2140 2140 /*
2141 2141 * Migrate pages marked for migration.
2142 2142 */
2143 2143 if (lgrp_optimizations())
2144 2144 page_migrate(seg, shm_addr, ppa, npages);
2145 2145
2146 2146 for (; pidx < npages; a += pgsz, pidx += pgcnt) {
2147 2147 sz = MIN(pgsz, ptob(npages - pidx));
2148 2148 hat_memload_array(sptseg->s_as->a_hat,
2149 2149 a, sz, &ppa[pidx],
2150 2150 sptd->spt_prot, HAT_LOAD_SHARE);
2151 2151 }
2152 2152
2153 2153 /*
2154 2154 * And now drop the SE_SHARED lock(s).
2155 2155 */
2156 2156 for (i = 0; i < npages; i++)
2157 2157 page_unlock(ppa[i]);
2158 2158 }
2159 2159 AS_LOCK_EXIT(sptseg->s_as, &sptseg->s_as->a_lock);
2160 2160
2161 2161 kmem_free(ppa, sizeof (page_t *) * npages);
2162 2162 return (0);
2163 2163 case F_SOFTUNLOCK:
2164 2164
2165 2165 /*
2166 2166 * This is a bit ugly, we pass in the real seg pointer,
2167 2167 * but the sptseg_addr is the virtual address within the
2168 2168 * dummy seg.
2169 2169 */
2170 2170 segspt_softunlock(seg, sptseg_addr, ptob(npages), rw);
2171 2171 return (0);
2172 2172
2173 2173 case F_PROT:
2174 2174
2175 2175 /*
2176 2176 * This takes care of the unusual case where a user
2177 2177 * allocates a stack in shared memory and a register
2178 2178 * window overflow is written to that stack page before
2179 2179 * it is otherwise modified.
2180 2180 *
2181 2181 * We can get away with this because ISM segments are
2182 2182 * always rw. Other than this unusual case, there
2183 2183 * should be no instances of protection violations.
2184 2184 */
2185 2185 return (0);
2186 2186
2187 2187 default:
2188 2188 #ifdef DEBUG
2189 2189 cmn_err(CE_WARN, "segspt_shmfault default type?");
2190 2190 #endif
2191 2191 return (FC_NOMAP);
2192 2192 }
2193 2193 }
2194 2194
2195 2195 /*ARGSUSED*/
2196 2196 static faultcode_t
2197 2197 segspt_shmfaulta(struct seg *seg, caddr_t addr)
2198 2198 {
2199 2199 return (0);
2200 2200 }
2201 2201
2202 2202 /*ARGSUSED*/
2203 2203 static int
2204 2204 segspt_shmkluster(struct seg *seg, caddr_t addr, ssize_t delta)
2205 2205 {
2206 2206 return (0);
2207 2207 }
2208 2208
2209 2209 /*
2210 2210 * duplicate the shared page tables
2211 2211 */
2212 2212 int
2213 2213 segspt_shmdup(struct seg *seg, struct seg *newseg)
2214 2214 {
2215 2215 struct shm_data *shmd = (struct shm_data *)seg->s_data;
2216 2216 struct anon_map *amp = shmd->shm_amp;
2217 2217 struct shm_data *shmd_new;
2218 2218 struct seg *spt_seg = shmd->shm_sptseg;
2219 2219 struct spt_data *sptd = spt_seg->s_data;
2220 2220 int error = 0;
2221 2221
2222 2222 ASSERT(seg->s_as && AS_WRITE_HELD(seg->s_as, &seg->s_as->a_lock));
2223 2223
2224 2224 shmd_new = kmem_zalloc((sizeof (*shmd_new)), KM_SLEEP);
2225 2225 newseg->s_data = (void *)shmd_new;
2226 2226 shmd_new->shm_sptas = shmd->shm_sptas;
2227 2227 shmd_new->shm_amp = amp;
2228 2228 shmd_new->shm_sptseg = shmd->shm_sptseg;
2229 2229 newseg->s_ops = &segspt_shmops;
2230 2230 newseg->s_szc = seg->s_szc;
2231 2231 ASSERT(seg->s_szc == shmd->shm_sptseg->s_szc);
2232 2232
2233 2233 ANON_LOCK_ENTER(&->a_rwlock, RW_WRITER);
2234 2234 amp->refcnt++;
2235 2235 ANON_LOCK_EXIT(&->a_rwlock);
2236 2236
2237 2237 if (sptd->spt_flags & SHM_PAGEABLE) {
2238 2238 shmd_new->shm_vpage = kmem_zalloc(btopr(amp->size), KM_SLEEP);
2239 2239 shmd_new->shm_lckpgs = 0;
2240 2240 if (hat_supported(HAT_DYNAMIC_ISM_UNMAP, (void *)0)) {
2241 2241 if ((error = hat_share(newseg->s_as->a_hat,
2242 2242 newseg->s_base, shmd->shm_sptas->a_hat, SEGSPTADDR,
2243 2243 seg->s_size, seg->s_szc)) != 0) {
2244 2244 kmem_free(shmd_new->shm_vpage,
2245 2245 btopr(amp->size));
2246 2246 }
2247 2247 }
2248 2248 return (error);
2249 2249 } else {
2250 2250 return (hat_share(newseg->s_as->a_hat, newseg->s_base,
2251 2251 shmd->shm_sptas->a_hat, SEGSPTADDR, seg->s_size,
2252 2252 seg->s_szc));
2253 2253
2254 2254 }
2255 2255 }
2256 2256
2257 2257 /*ARGSUSED*/
2258 2258 int
2259 2259 segspt_shmcheckprot(struct seg *seg, caddr_t addr, size_t size, uint_t prot)
2260 2260 {
2261 2261 struct shm_data *shmd = (struct shm_data *)seg->s_data;
2262 2262 struct spt_data *sptd = (struct spt_data *)shmd->shm_sptseg->s_data;
2263 2263
2264 2264 ASSERT(seg->s_as && AS_LOCK_HELD(seg->s_as, &seg->s_as->a_lock));
2265 2265
2266 2266 /*
2267 2267 * ISM segment is always rw.
2268 2268 */
2269 2269 return (((sptd->spt_prot & prot) != prot) ? EACCES : 0);
2270 2270 }
2271 2271
2272 2272 /*
2273 2273 * Return an array of locked large pages, for empty slots allocate
2274 2274 * private zero-filled anon pages.
2275 2275 */
2276 2276 static int
2277 2277 spt_anon_getpages(
2278 2278 struct seg *sptseg,
2279 2279 caddr_t sptaddr,
2280 2280 size_t len,
2281 2281 page_t *ppa[])
2282 2282 {
2283 2283 struct spt_data *sptd = sptseg->s_data;
2284 2284 struct anon_map *amp = sptd->spt_amp;
2285 2285 enum seg_rw rw = sptd->spt_prot;
2286 2286 uint_t szc = sptseg->s_szc;
2287 2287 size_t pg_sz, share_sz = page_get_pagesize(szc);
2288 2288 pgcnt_t lp_npgs;
2289 2289 caddr_t lp_addr, e_sptaddr;
2290 2290 uint_t vpprot, ppa_szc = 0;
2291 2291 struct vpage *vpage = NULL;
2292 2292 ulong_t j, ppa_idx;
2293 2293 int err, ierr = 0;
2294 2294 pgcnt_t an_idx;
2295 2295 anon_sync_obj_t cookie;
2296 2296 int anon_locked = 0;
2297 2297 pgcnt_t amp_pgs;
2298 2298
2299 2299
2300 2300 ASSERT(IS_P2ALIGNED(sptaddr, share_sz) && IS_P2ALIGNED(len, share_sz));
2301 2301 ASSERT(len != 0);
2302 2302
2303 2303 pg_sz = share_sz;
2304 2304 lp_npgs = btop(pg_sz);
2305 2305 lp_addr = sptaddr;
2306 2306 e_sptaddr = sptaddr + len;
2307 2307 an_idx = seg_page(sptseg, sptaddr);
2308 2308 ppa_idx = 0;
2309 2309
2310 2310 ANON_LOCK_ENTER(&->a_rwlock, RW_READER);
2311 2311
2312 2312 amp_pgs = page_get_pagecnt(amp->a_szc);
2313 2313
2314 2314 /*CONSTCOND*/
2315 2315 while (1) {
2316 2316 for (; lp_addr < e_sptaddr;
2317 2317 an_idx += lp_npgs, lp_addr += pg_sz, ppa_idx += lp_npgs) {
2318 2318
2319 2319 /*
2320 2320 * If we're currently locked, and we get to a new
2321 2321 * page, unlock our current anon chunk.
2322 2322 */
2323 2323 if (anon_locked && P2PHASE(an_idx, amp_pgs) == 0) {
2324 2324 anon_array_exit(&cookie);
2325 2325 anon_locked = 0;
2326 2326 }
2327 2327 if (!anon_locked) {
2328 2328 anon_array_enter(amp, an_idx, &cookie);
2329 2329 anon_locked = 1;
2330 2330 }
2331 2331 ppa_szc = (uint_t)-1;
2332 2332 ierr = anon_map_getpages(amp, an_idx, szc, sptseg,
2333 2333 lp_addr, sptd->spt_prot, &vpprot, &ppa[ppa_idx],
2334 2334 &ppa_szc, vpage, rw, 0, segvn_anypgsz, 0, kcred);
2335 2335
2336 2336 if (ierr != 0) {
2337 2337 if (ierr > 0) {
2338 2338 err = FC_MAKE_ERR(ierr);
2339 2339 goto lpgs_err;
2340 2340 }
2341 2341 break;
2342 2342 }
2343 2343 }
2344 2344 if (lp_addr == e_sptaddr) {
2345 2345 break;
2346 2346 }
2347 2347 ASSERT(lp_addr < e_sptaddr);
2348 2348
2349 2349 /*
2350 2350 * ierr == -1 means we failed to allocate a large page.
2351 2351 * so do a size down operation.
2352 2352 *
2353 2353 * ierr == -2 means some other process that privately shares
2354 2354 * pages with this process has allocated a larger page and we
2355 2355 * need to retry with larger pages. So do a size up
2356 2356 * operation. This relies on the fact that large pages are
2357 2357 * never partially shared i.e. if we share any constituent
2358 2358 * page of a large page with another process we must share the
2359 2359 * entire large page. Note this cannot happen for SOFTLOCK
2360 2360 * case, unless current address (lpaddr) is at the beginning
2361 2361 * of the next page size boundary because the other process
2362 2362 * couldn't have relocated locked pages.
2363 2363 */
2364 2364 ASSERT(ierr == -1 || ierr == -2);
2365 2365 if (segvn_anypgsz) {
2366 2366 ASSERT(ierr == -2 || szc != 0);
2367 2367 ASSERT(ierr == -1 || szc < sptseg->s_szc);
2368 2368 szc = (ierr == -1) ? szc - 1 : szc + 1;
2369 2369 } else {
2370 2370 /*
2371 2371 * For faults and segvn_anypgsz == 0
2372 2372 * we need to be careful not to loop forever
2373 2373 * if existing page is found with szc other
2374 2374 * than 0 or seg->s_szc. This could be due
2375 2375 * to page relocations on behalf of DR or
2376 2376 * more likely large page creation. For this
2377 2377 * case simply re-size to existing page's szc
2378 2378 * if returned by anon_map_getpages().
2379 2379 */
2380 2380 if (ppa_szc == (uint_t)-1) {
2381 2381 szc = (ierr == -1) ? 0 : sptseg->s_szc;
2382 2382 } else {
2383 2383 ASSERT(ppa_szc <= sptseg->s_szc);
2384 2384 ASSERT(ierr == -2 || ppa_szc < szc);
2385 2385 ASSERT(ierr == -1 || ppa_szc > szc);
2386 2386 szc = ppa_szc;
2387 2387 }
2388 2388 }
2389 2389 pg_sz = page_get_pagesize(szc);
2390 2390 lp_npgs = btop(pg_sz);
2391 2391 ASSERT(IS_P2ALIGNED(lp_addr, pg_sz));
2392 2392 }
2393 2393 if (anon_locked) {
2394 2394 anon_array_exit(&cookie);
2395 2395 }
2396 2396 ANON_LOCK_EXIT(&->a_rwlock);
2397 2397 return (0);
2398 2398
2399 2399 lpgs_err:
2400 2400 if (anon_locked) {
2401 2401 anon_array_exit(&cookie);
2402 2402 }
2403 2403 ANON_LOCK_EXIT(&->a_rwlock);
2404 2404 for (j = 0; j < ppa_idx; j++)
2405 2405 page_unlock(ppa[j]);
2406 2406 return (err);
2407 2407 }
2408 2408
2409 2409 /*
2410 2410 * count the number of bytes in a set of spt pages that are currently not
2411 2411 * locked
2412 2412 */
2413 2413 static rctl_qty_t
2414 2414 spt_unlockedbytes(pgcnt_t npages, page_t **ppa)
2415 2415 {
2416 2416 ulong_t i;
2417 2417 rctl_qty_t unlocked = 0;
2418 2418
2419 2419 for (i = 0; i < npages; i++) {
2420 2420 if (ppa[i]->p_lckcnt == 0)
2421 2421 unlocked += PAGESIZE;
2422 2422 }
2423 2423 return (unlocked);
2424 2424 }
2425 2425
2426 2426 extern u_longlong_t randtick(void);
2427 2427 /* number of locks to reserve/skip by spt_lockpages() and spt_unlockpages() */
2428 2428 #define NLCK (NCPU_P2)
2429 2429 /* Random number with a range [0, n-1], n must be power of two */
2430 2430 #define RAND_P2(n) \
2431 2431 ((((long)curthread >> PTR24_LSB) ^ (long)randtick()) & ((n) - 1))
2432 2432
2433 2433 int
2434 2434 spt_lockpages(struct seg *seg, pgcnt_t anon_index, pgcnt_t npages,
2435 2435 page_t **ppa, ulong_t *lockmap, size_t pos,
2436 2436 rctl_qty_t *locked)
2437 2437 {
2438 2438 struct shm_data *shmd = seg->s_data;
2439 2439 struct spt_data *sptd = shmd->shm_sptseg->s_data;
2440 2440 ulong_t i;
2441 2441 int kernel;
2442 2442 pgcnt_t nlck = 0;
2443 2443 int rv = 0;
2444 2444 int use_reserved = 1;
2445 2445
2446 2446 /* return the number of bytes actually locked */
2447 2447 *locked = 0;
2448 2448
2449 2449 /*
2450 2450 * To avoid contention on freemem_lock, availrmem and pages_locked
2451 2451 * global counters are updated only every nlck locked pages instead of
2452 2452 * every time. Reserve nlck locks up front and deduct from this
2453 2453 * reservation for each page that requires a lock. When the reservation
2454 2454 * is consumed, reserve again. nlck is randomized, so the competing
2455 2455 * threads do not fall into a cyclic lock contention pattern. When
2456 2456 * memory is low, the lock ahead is disabled, and instead page_pp_lock()
2457 2457 * is used to lock pages.
2458 2458 */
2459 2459 for (i = 0; i < npages; anon_index++, pos++, i++) {
2460 2460 if (nlck == 0 && use_reserved == 1) {
2461 2461 nlck = NLCK + RAND_P2(NLCK);
2462 2462 /* if fewer loops left, decrease nlck */
2463 2463 nlck = MIN(nlck, npages - i);
2464 2464 /*
2465 2465 * Reserve nlck locks up front and deduct from this
2466 2466 * reservation for each page that requires a lock. When
2467 2467 * the reservation is consumed, reserve again.
2468 2468 */
2469 2469 mutex_enter(&freemem_lock);
2470 2470 if ((availrmem - nlck) < pages_pp_maximum) {
2471 2471 /* Do not do advance memory reserves */
2472 2472 use_reserved = 0;
2473 2473 } else {
2474 2474 availrmem -= nlck;
2475 2475 pages_locked += nlck;
2476 2476 }
2477 2477 mutex_exit(&freemem_lock);
2478 2478 }
2479 2479 if (!(shmd->shm_vpage[anon_index] & DISM_PG_LOCKED)) {
2480 2480 if (sptd->spt_ppa_lckcnt[anon_index] <
2481 2481 (ushort_t)DISM_LOCK_MAX) {
2482 2482 if (++sptd->spt_ppa_lckcnt[anon_index] ==
2483 2483 (ushort_t)DISM_LOCK_MAX) {
2484 2484 cmn_err(CE_WARN,
2485 2485 "DISM page lock limit "
2486 2486 "reached on DISM offset 0x%lx\n",
2487 2487 anon_index << PAGESHIFT);
2488 2488 }
2489 2489 kernel = (sptd->spt_ppa &&
2490 2490 sptd->spt_ppa[anon_index]);
2491 2491 if (!page_pp_lock(ppa[i], 0, kernel ||
2492 2492 use_reserved)) {
2493 2493 sptd->spt_ppa_lckcnt[anon_index]--;
2494 2494 rv = EAGAIN;
2495 2495 break;
2496 2496 }
2497 2497 /* if this is a newly locked page, count it */
2498 2498 if (ppa[i]->p_lckcnt == 1) {
2499 2499 if (kernel == 0 && use_reserved == 1)
2500 2500 nlck--;
2501 2501 *locked += PAGESIZE;
2502 2502 }
2503 2503 shmd->shm_lckpgs++;
2504 2504 shmd->shm_vpage[anon_index] |= DISM_PG_LOCKED;
2505 2505 if (lockmap != NULL)
2506 2506 BT_SET(lockmap, pos);
2507 2507 }
2508 2508 }
2509 2509 }
2510 2510 /* Return unused lock reservation */
2511 2511 if (nlck != 0 && use_reserved == 1) {
2512 2512 mutex_enter(&freemem_lock);
2513 2513 availrmem += nlck;
2514 2514 pages_locked -= nlck;
2515 2515 mutex_exit(&freemem_lock);
2516 2516 }
2517 2517
2518 2518 return (rv);
2519 2519 }
2520 2520
2521 2521 int
2522 2522 spt_unlockpages(struct seg *seg, pgcnt_t anon_index, pgcnt_t npages,
2523 2523 rctl_qty_t *unlocked)
2524 2524 {
2525 2525 struct shm_data *shmd = seg->s_data;
2526 2526 struct spt_data *sptd = shmd->shm_sptseg->s_data;
2527 2527 struct anon_map *amp = sptd->spt_amp;
2528 2528 struct anon *ap;
2529 2529 struct vnode *vp;
2530 2530 u_offset_t off;
2531 2531 struct page *pp;
2532 2532 int kernel;
2533 2533 anon_sync_obj_t cookie;
2534 2534 ulong_t i;
2535 2535 pgcnt_t nlck = 0;
2536 2536 pgcnt_t nlck_limit = NLCK;
2537 2537
2538 2538 ANON_LOCK_ENTER(&->a_rwlock, RW_READER);
2539 2539 for (i = 0; i < npages; i++, anon_index++) {
2540 2540 if (shmd->shm_vpage[anon_index] & DISM_PG_LOCKED) {
2541 2541 anon_array_enter(amp, anon_index, &cookie);
2542 2542 ap = anon_get_ptr(amp->ahp, anon_index);
2543 2543 ASSERT(ap);
2544 2544
2545 2545 swap_xlate(ap, &vp, &off);
2546 2546 anon_array_exit(&cookie);
2547 2547 pp = page_lookup(vp, off, SE_SHARED);
2548 2548 ASSERT(pp);
2549 2549 /*
2550 2550 * availrmem is decremented only for pages which are not
2551 2551 * in seg pcache, for pages in seg pcache availrmem was
2552 2552 * decremented in _dismpagelock()
2553 2553 */
2554 2554 kernel = (sptd->spt_ppa && sptd->spt_ppa[anon_index]);
2555 2555 ASSERT(pp->p_lckcnt > 0);
2556 2556
2557 2557 /*
2558 2558 * lock page but do not change availrmem, we do it
2559 2559 * ourselves every nlck loops.
2560 2560 */
2561 2561 page_pp_unlock(pp, 0, 1);
2562 2562 if (pp->p_lckcnt == 0) {
2563 2563 if (kernel == 0)
2564 2564 nlck++;
2565 2565 *unlocked += PAGESIZE;
2566 2566 }
2567 2567 page_unlock(pp);
2568 2568 shmd->shm_vpage[anon_index] &= ~DISM_PG_LOCKED;
2569 2569 sptd->spt_ppa_lckcnt[anon_index]--;
2570 2570 shmd->shm_lckpgs--;
2571 2571 }
2572 2572
2573 2573 /*
2574 2574 * To reduce freemem_lock contention, do not update availrmem
2575 2575 * until at least NLCK pages have been unlocked.
2576 2576 * 1. No need to update if nlck is zero
2577 2577 * 2. Always update if the last iteration
2578 2578 */
2579 2579 if (nlck > 0 && (nlck == nlck_limit || i == npages - 1)) {
2580 2580 mutex_enter(&freemem_lock);
2581 2581 availrmem += nlck;
2582 2582 pages_locked -= nlck;
2583 2583 mutex_exit(&freemem_lock);
2584 2584 nlck = 0;
2585 2585 nlck_limit = NLCK + RAND_P2(NLCK);
2586 2586 }
2587 2587 }
2588 2588 ANON_LOCK_EXIT(&->a_rwlock);
2589 2589
2590 2590 return (0);
2591 2591 }
2592 2592
2593 2593 /*ARGSUSED*/
2594 2594 static int
2595 2595 segspt_shmlockop(struct seg *seg, caddr_t addr, size_t len,
2596 2596 int attr, int op, ulong_t *lockmap, size_t pos)
2597 2597 {
2598 2598 struct shm_data *shmd = seg->s_data;
2599 2599 struct seg *sptseg = shmd->shm_sptseg;
2600 2600 struct spt_data *sptd = sptseg->s_data;
2601 2601 struct kshmid *sp = sptd->spt_amp->a_sp;
2602 2602 pgcnt_t npages, a_npages;
2603 2603 page_t **ppa;
2604 2604 pgcnt_t an_idx, a_an_idx, ppa_idx;
2605 2605 caddr_t spt_addr, a_addr; /* spt and aligned address */
2606 2606 size_t a_len; /* aligned len */
2607 2607 size_t share_sz;
2608 2608 ulong_t i;
2609 2609 int sts = 0;
2610 2610 rctl_qty_t unlocked = 0;
2611 2611 rctl_qty_t locked = 0;
2612 2612 struct proc *p = curproc;
2613 2613 kproject_t *proj;
2614 2614
2615 2615 ASSERT(seg->s_as && AS_LOCK_HELD(seg->s_as, &seg->s_as->a_lock));
2616 2616 ASSERT(sp != NULL);
2617 2617
2618 2618 if ((sptd->spt_flags & SHM_PAGEABLE) == 0) {
2619 2619 return (0);
2620 2620 }
2621 2621
2622 2622 addr = (caddr_t)((uintptr_t)addr & (uintptr_t)PAGEMASK);
2623 2623 an_idx = seg_page(seg, addr);
2624 2624 npages = btopr(len);
2625 2625
2626 2626 if (an_idx + npages > btopr(shmd->shm_amp->size)) {
2627 2627 return (ENOMEM);
2628 2628 }
2629 2629
2630 2630 /*
2631 2631 * A shm's project never changes, so no lock needed.
2632 2632 * The shm has a hold on the project, so it will not go away.
2633 2633 * Since we have a mapping to shm within this zone, we know
2634 2634 * that the zone will not go away.
2635 2635 */
2636 2636 proj = sp->shm_perm.ipc_proj;
2637 2637
2638 2638 if (op == MC_LOCK) {
2639 2639
2640 2640 /*
2641 2641 * Need to align addr and size request if they are not
2642 2642 * aligned so we can always allocate large page(s) however
2643 2643 * we only lock what was requested in initial request.
2644 2644 */
2645 2645 share_sz = page_get_pagesize(sptseg->s_szc);
2646 2646 a_addr = (caddr_t)P2ALIGN((uintptr_t)(addr), share_sz);
2647 2647 a_len = P2ROUNDUP((uintptr_t)(((addr + len) - a_addr)),
2648 2648 share_sz);
2649 2649 a_npages = btop(a_len);
2650 2650 a_an_idx = seg_page(seg, a_addr);
2651 2651 spt_addr = sptseg->s_base + ptob(a_an_idx);
2652 2652 ppa_idx = an_idx - a_an_idx;
2653 2653
2654 2654 if ((ppa = kmem_zalloc(((sizeof (page_t *)) * a_npages),
2655 2655 KM_NOSLEEP)) == NULL) {
2656 2656 return (ENOMEM);
2657 2657 }
2658 2658
2659 2659 /*
2660 2660 * Don't cache any new pages for IO and
2661 2661 * flush any cached pages.
2662 2662 */
2663 2663 mutex_enter(&sptd->spt_lock);
2664 2664 if (sptd->spt_ppa != NULL)
2665 2665 sptd->spt_flags |= DISM_PPA_CHANGED;
2666 2666
2667 2667 sts = spt_anon_getpages(sptseg, spt_addr, a_len, ppa);
2668 2668 if (sts != 0) {
2669 2669 mutex_exit(&sptd->spt_lock);
2670 2670 kmem_free(ppa, ((sizeof (page_t *)) * a_npages));
2671 2671 return (sts);
2672 2672 }
2673 2673
2674 2674 mutex_enter(&sp->shm_mlock);
2675 2675 /* enforce locked memory rctl */
2676 2676 unlocked = spt_unlockedbytes(npages, &ppa[ppa_idx]);
2677 2677
2678 2678 mutex_enter(&p->p_lock);
2679 2679 if (rctl_incr_locked_mem(p, proj, unlocked, 0)) {
2680 2680 mutex_exit(&p->p_lock);
2681 2681 sts = EAGAIN;
2682 2682 } else {
2683 2683 mutex_exit(&p->p_lock);
2684 2684 sts = spt_lockpages(seg, an_idx, npages,
2685 2685 &ppa[ppa_idx], lockmap, pos, &locked);
2686 2686
2687 2687 /*
2688 2688 * correct locked count if not all pages could be
2689 2689 * locked
2690 2690 */
2691 2691 if ((unlocked - locked) > 0) {
2692 2692 rctl_decr_locked_mem(NULL, proj,
2693 2693 (unlocked - locked), 0);
2694 2694 }
2695 2695 }
2696 2696 /*
2697 2697 * unlock pages
2698 2698 */
2699 2699 for (i = 0; i < a_npages; i++)
2700 2700 page_unlock(ppa[i]);
2701 2701 if (sptd->spt_ppa != NULL)
2702 2702 sptd->spt_flags |= DISM_PPA_CHANGED;
2703 2703 mutex_exit(&sp->shm_mlock);
2704 2704 mutex_exit(&sptd->spt_lock);
2705 2705
2706 2706 kmem_free(ppa, ((sizeof (page_t *)) * a_npages));
2707 2707
2708 2708 } else if (op == MC_UNLOCK) { /* unlock */
2709 2709 page_t **ppa;
2710 2710
2711 2711 mutex_enter(&sptd->spt_lock);
2712 2712 if (shmd->shm_lckpgs == 0) {
2713 2713 mutex_exit(&sptd->spt_lock);
2714 2714 return (0);
2715 2715 }
2716 2716 /*
2717 2717 * Don't cache new IO pages.
2718 2718 */
2719 2719 if (sptd->spt_ppa != NULL)
2720 2720 sptd->spt_flags |= DISM_PPA_CHANGED;
2721 2721
2722 2722 mutex_enter(&sp->shm_mlock);
2723 2723 sts = spt_unlockpages(seg, an_idx, npages, &unlocked);
2724 2724 if ((ppa = sptd->spt_ppa) != NULL)
2725 2725 sptd->spt_flags |= DISM_PPA_CHANGED;
2726 2726 mutex_exit(&sptd->spt_lock);
2727 2727
2728 2728 rctl_decr_locked_mem(NULL, proj, unlocked, 0);
2729 2729 mutex_exit(&sp->shm_mlock);
2730 2730
2731 2731 if (ppa != NULL)
2732 2732 seg_ppurge_wiredpp(ppa);
2733 2733 }
2734 2734 return (sts);
2735 2735 }
2736 2736
2737 2737 /*ARGSUSED*/
2738 2738 int
2739 2739 segspt_shmgetprot(struct seg *seg, caddr_t addr, size_t len, uint_t *protv)
2740 2740 {
2741 2741 struct shm_data *shmd = (struct shm_data *)seg->s_data;
2742 2742 struct spt_data *sptd = (struct spt_data *)shmd->shm_sptseg->s_data;
2743 2743 spgcnt_t pgno = seg_page(seg, addr+len) - seg_page(seg, addr) + 1;
2744 2744
2745 2745 ASSERT(seg->s_as && AS_LOCK_HELD(seg->s_as, &seg->s_as->a_lock));
2746 2746
2747 2747 /*
2748 2748 * ISM segment is always rw.
2749 2749 */
2750 2750 while (--pgno >= 0)
2751 2751 *protv++ = sptd->spt_prot;
2752 2752 return (0);
2753 2753 }
2754 2754
2755 2755 /*ARGSUSED*/
2756 2756 u_offset_t
2757 2757 segspt_shmgetoffset(struct seg *seg, caddr_t addr)
2758 2758 {
2759 2759 ASSERT(seg->s_as && AS_LOCK_HELD(seg->s_as, &seg->s_as->a_lock));
2760 2760
2761 2761 /* Offset does not matter in ISM memory */
2762 2762
2763 2763 return ((u_offset_t)0);
2764 2764 }
2765 2765
2766 2766 /* ARGSUSED */
2767 2767 int
2768 2768 segspt_shmgettype(struct seg *seg, caddr_t addr)
2769 2769 {
2770 2770 struct shm_data *shmd = (struct shm_data *)seg->s_data;
2771 2771 struct spt_data *sptd = (struct spt_data *)shmd->shm_sptseg->s_data;
2772 2772
2773 2773 ASSERT(seg->s_as && AS_LOCK_HELD(seg->s_as, &seg->s_as->a_lock));
2774 2774
2775 2775 /*
2776 2776 * The shared memory mapping is always MAP_SHARED, SWAP is only
2777 2777 * reserved for DISM
2778 2778 */
2779 2779 return (MAP_SHARED |
2780 2780 ((sptd->spt_flags & SHM_PAGEABLE) ? 0 : MAP_NORESERVE));
2781 2781 }
2782 2782
2783 2783 /*ARGSUSED*/
2784 2784 int
2785 2785 segspt_shmgetvp(struct seg *seg, caddr_t addr, struct vnode **vpp)
2786 2786 {
2787 2787 struct shm_data *shmd = (struct shm_data *)seg->s_data;
2788 2788 struct spt_data *sptd = (struct spt_data *)shmd->shm_sptseg->s_data;
2789 2789
2790 2790 ASSERT(seg->s_as && AS_LOCK_HELD(seg->s_as, &seg->s_as->a_lock));
2791 2791
2792 2792 *vpp = sptd->spt_vp;
2793 2793 return (0);
2794 2794 }
2795 2795
2796 2796 /*
2797 2797 * We need to wait for pending IO to complete to a DISM segment in order for
2798 2798 * pages to get kicked out of the seg_pcache. 120 seconds should be more
2799 2799 * than enough time to wait.
2800 2800 */
2801 2801 static clock_t spt_pcache_wait = 120;
2802 2802
2803 2803 /*ARGSUSED*/
2804 2804 static int
2805 2805 segspt_shmadvise(struct seg *seg, caddr_t addr, size_t len, uint_t behav)
2806 2806 {
2807 2807 struct shm_data *shmd = (struct shm_data *)seg->s_data;
2808 2808 struct spt_data *sptd = (struct spt_data *)shmd->shm_sptseg->s_data;
2809 2809 struct anon_map *amp;
2810 2810 pgcnt_t pg_idx;
2811 2811 ushort_t gen;
2812 2812 clock_t end_lbolt;
2813 2813 int writer;
2814 2814 page_t **ppa;
2815 2815
2816 2816 ASSERT(seg->s_as && AS_LOCK_HELD(seg->s_as, &seg->s_as->a_lock));
2817 2817
2818 2818 if (behav == MADV_FREE) {
2819 2819 if ((sptd->spt_flags & SHM_PAGEABLE) == 0)
2820 2820 return (0);
2821 2821
2822 2822 amp = sptd->spt_amp;
2823 2823 pg_idx = seg_page(seg, addr);
2824 2824
2825 2825 mutex_enter(&sptd->spt_lock);
2826 2826 if ((ppa = sptd->spt_ppa) == NULL) {
2827 2827 mutex_exit(&sptd->spt_lock);
2828 2828 ANON_LOCK_ENTER(&->a_rwlock, RW_READER);
2829 2829 anon_disclaim(amp, pg_idx, len);
2830 2830 ANON_LOCK_EXIT(&->a_rwlock);
2831 2831 return (0);
2832 2832 }
2833 2833
2834 2834 sptd->spt_flags |= DISM_PPA_CHANGED;
2835 2835 gen = sptd->spt_gen;
2836 2836
2837 2837 mutex_exit(&sptd->spt_lock);
2838 2838
2839 2839 /*
2840 2840 * Purge all DISM cached pages
2841 2841 */
2842 2842 seg_ppurge_wiredpp(ppa);
2843 2843
2844 2844 /*
2845 2845 * Drop the AS_LOCK so that other threads can grab it
2846 2846 * in the as_pageunlock path and hopefully get the segment
2847 2847 * kicked out of the seg_pcache. We bump the shm_softlockcnt
2848 2848 * to keep this segment resident.
2849 2849 */
2850 2850 writer = AS_WRITE_HELD(seg->s_as, &seg->s_as->a_lock);
2851 2851 atomic_inc_ulong((ulong_t *)(&(shmd->shm_softlockcnt)));
2852 2852 AS_LOCK_EXIT(seg->s_as, &seg->s_as->a_lock);
2853 2853
2854 2854 mutex_enter(&sptd->spt_lock);
2855 2855
2856 2856 end_lbolt = ddi_get_lbolt() + (hz * spt_pcache_wait);
2857 2857
2858 2858 /*
2859 2859 * Try to wait for pages to get kicked out of the seg_pcache.
2860 2860 */
2861 2861 while (sptd->spt_gen == gen &&
2862 2862 (sptd->spt_flags & DISM_PPA_CHANGED) &&
2863 2863 ddi_get_lbolt() < end_lbolt) {
2864 2864 if (!cv_timedwait_sig(&sptd->spt_cv,
2865 2865 &sptd->spt_lock, end_lbolt)) {
2866 2866 break;
2867 2867 }
2868 2868 }
2869 2869
2870 2870 mutex_exit(&sptd->spt_lock);
2871 2871
2872 2872 /* Regrab the AS_LOCK and release our hold on the segment */
2873 2873 AS_LOCK_ENTER(seg->s_as, &seg->s_as->a_lock,
2874 2874 writer ? RW_WRITER : RW_READER);
2875 2875 atomic_dec_ulong((ulong_t *)(&(shmd->shm_softlockcnt)));
2876 2876 if (shmd->shm_softlockcnt <= 0) {
2877 2877 if (AS_ISUNMAPWAIT(seg->s_as)) {
2878 2878 mutex_enter(&seg->s_as->a_contents);
2879 2879 if (AS_ISUNMAPWAIT(seg->s_as)) {
2880 2880 AS_CLRUNMAPWAIT(seg->s_as);
2881 2881 cv_broadcast(&seg->s_as->a_cv);
2882 2882 }
2883 2883 mutex_exit(&seg->s_as->a_contents);
2884 2884 }
2885 2885 }
2886 2886
2887 2887 ANON_LOCK_ENTER(&->a_rwlock, RW_READER);
2888 2888 anon_disclaim(amp, pg_idx, len);
2889 2889 ANON_LOCK_EXIT(&->a_rwlock);
2890 2890 } else if (lgrp_optimizations() && (behav == MADV_ACCESS_LWP ||
2891 2891 behav == MADV_ACCESS_MANY || behav == MADV_ACCESS_DEFAULT)) {
2892 2892 int already_set;
2893 2893 ulong_t anon_index;
2894 2894 lgrp_mem_policy_t policy;
2895 2895 caddr_t shm_addr;
2896 2896 size_t share_size;
2897 2897 size_t size;
2898 2898 struct seg *sptseg = shmd->shm_sptseg;
2899 2899 caddr_t sptseg_addr;
2900 2900
2901 2901 /*
2902 2902 * Align address and length to page size of underlying segment
2903 2903 */
2904 2904 share_size = page_get_pagesize(shmd->shm_sptseg->s_szc);
2905 2905 shm_addr = (caddr_t)P2ALIGN((uintptr_t)(addr), share_size);
2906 2906 size = P2ROUNDUP((uintptr_t)(((addr + len) - shm_addr)),
2907 2907 share_size);
2908 2908
2909 2909 amp = shmd->shm_amp;
2910 2910 anon_index = seg_page(seg, shm_addr);
2911 2911
2912 2912 /*
2913 2913 * And now we may have to adjust size downward if we have
2914 2914 * exceeded the realsize of the segment or initial anon
2915 2915 * allocations.
2916 2916 */
2917 2917 sptseg_addr = sptseg->s_base + ptob(anon_index);
2918 2918 if ((sptseg_addr + size) >
2919 2919 (sptseg->s_base + sptd->spt_realsize))
2920 2920 size = (sptseg->s_base + sptd->spt_realsize) -
2921 2921 sptseg_addr;
2922 2922
2923 2923 /*
2924 2924 * Set memory allocation policy for this segment
2925 2925 */
2926 2926 policy = lgrp_madv_to_policy(behav, len, MAP_SHARED);
2927 2927 already_set = lgrp_shm_policy_set(policy, amp, anon_index,
2928 2928 NULL, 0, len);
2929 2929
2930 2930 /*
2931 2931 * If random memory allocation policy set already,
2932 2932 * don't bother reapplying it.
2933 2933 */
2934 2934 if (already_set && !LGRP_MEM_POLICY_REAPPLICABLE(policy))
2935 2935 return (0);
2936 2936
2937 2937 /*
2938 2938 * Mark any existing pages in the given range for
2939 2939 * migration, flushing the I/O page cache, and using
2940 2940 * underlying segment to calculate anon index and get
2941 2941 * anonmap and vnode pointer from
2942 2942 */
2943 2943 if (shmd->shm_softlockcnt > 0)
2944 2944 segspt_purge(seg);
2945 2945
2946 2946 page_mark_migrate(seg, shm_addr, size, amp, 0, NULL, 0, 0);
2947 2947 }
2948 2948
2949 2949 return (0);
2950 2950 }
2951 2951
2952 2952 /*ARGSUSED*/
2953 2953 void
2954 2954 segspt_shmdump(struct seg *seg)
2955 2955 {
2956 2956 /* no-op for ISM segment */
2957 2957 }
2958 2958
2959 2959 /*
2960 2960 * get a memory ID for an addr in a given segment
2961 2961 */
2962 2962 static int
2963 2963 segspt_shmgetmemid(struct seg *seg, caddr_t addr, memid_t *memidp)
2964 2964 {
2965 2965 struct shm_data *shmd = (struct shm_data *)seg->s_data;
2966 2966 struct anon *ap;
2967 2967 size_t anon_index;
2968 2968 struct anon_map *amp = shmd->shm_amp;
2969 2969 struct spt_data *sptd = shmd->shm_sptseg->s_data;
2970 2970 struct seg *sptseg = shmd->shm_sptseg;
2971 2971 anon_sync_obj_t cookie;
2972 2972
2973 2973 anon_index = seg_page(seg, addr);
2974 2974
2975 2975 if (addr > (seg->s_base + sptd->spt_realsize)) {
2976 2976 return (EFAULT);
2977 2977 }
2978 2978
2979 2979 ANON_LOCK_ENTER(&->a_rwlock, RW_READER);
2980 2980 anon_array_enter(amp, anon_index, &cookie);
2981 2981 ap = anon_get_ptr(amp->ahp, anon_index);
2982 2982 if (ap == NULL) {
2983 2983 struct page *pp;
2984 2984 caddr_t spt_addr = sptseg->s_base + ptob(anon_index);
2985 2985
2986 2986 pp = anon_zero(sptseg, spt_addr, &ap, kcred);
2987 2987 if (pp == NULL) {
2988 2988 anon_array_exit(&cookie);
2989 2989 ANON_LOCK_EXIT(&->a_rwlock);
2990 2990 return (ENOMEM);
2991 2991 }
2992 2992 (void) anon_set_ptr(amp->ahp, anon_index, ap, ANON_SLEEP);
2993 2993 page_unlock(pp);
2994 2994 }
2995 2995 anon_array_exit(&cookie);
2996 2996 ANON_LOCK_EXIT(&->a_rwlock);
2997 2997 memidp->val[0] = (uintptr_t)ap;
2998 2998 memidp->val[1] = (uintptr_t)addr & PAGEOFFSET;
2999 2999 return (0);
3000 3000 }
3001 3001
3002 3002 /*
3003 3003 * Get memory allocation policy info for specified address in given segment
3004 3004 */
3005 3005 static lgrp_mem_policy_info_t *
3006 3006 segspt_shmgetpolicy(struct seg *seg, caddr_t addr)
3007 3007 {
3008 3008 struct anon_map *amp;
3009 3009 ulong_t anon_index;
3010 3010 lgrp_mem_policy_info_t *policy_info;
3011 3011 struct shm_data *shm_data;
3012 3012
3013 3013 ASSERT(seg != NULL);
3014 3014
3015 3015 /*
3016 3016 * Get anon_map from segshm
3017 3017 *
3018 3018 * Assume that no lock needs to be held on anon_map, since
3019 3019 * it should be protected by its reference count which must be
3020 3020 * nonzero for an existing segment
3021 3021 * Need to grab readers lock on policy tree though
3022 3022 */
3023 3023 shm_data = (struct shm_data *)seg->s_data;
3024 3024 if (shm_data == NULL)
3025 3025 return (NULL);
3026 3026 amp = shm_data->shm_amp;
3027 3027 ASSERT(amp->refcnt != 0);
3028 3028
3029 3029 /*
3030 3030 * Get policy info
3031 3031 *
3032 3032 * Assume starting anon index of 0
3033 3033 */
3034 3034 anon_index = seg_page(seg, addr);
3035 3035 policy_info = lgrp_shm_policy_get(amp, anon_index, NULL, 0);
3036 3036
3037 3037 return (policy_info);
3038 3038 }
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