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--- old/usr/src/uts/sparc/v9/vm/seg_nf.c
+++ new/usr/src/uts/sparc/v9/vm/seg_nf.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 2006 Sun Microsystems, Inc. All rights reserved.
23 23 * Use is subject to license terms.
24 24 */
25 25
26 26 /* Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T */
27 27 /* All Rights Reserved */
28 28
29 29 /*
30 30 * Portions of this source code were derived from Berkeley 4.3 BSD
31 31 * under license from the Regents of the University of California.
32 32 */
33 33
34 34 /*
35 35 * VM - segment for non-faulting loads.
36 36 */
37 37
38 38 #include <sys/types.h>
39 39 #include <sys/t_lock.h>
40 40 #include <sys/param.h>
41 41 #include <sys/mman.h>
42 42 #include <sys/errno.h>
43 43 #include <sys/kmem.h>
44 44 #include <sys/cmn_err.h>
45 45 #include <sys/vnode.h>
46 46 #include <sys/proc.h>
47 47 #include <sys/conf.h>
48 48 #include <sys/debug.h>
49 49 #include <sys/archsystm.h>
50 50 #include <sys/lgrp.h>
51 51
52 52 #include <vm/page.h>
53 53 #include <vm/hat.h>
54 54 #include <vm/as.h>
55 55 #include <vm/seg.h>
56 56 #include <vm/vpage.h>
57 57
58 58 /*
59 59 * Private seg op routines.
60 60 */
61 61 static int segnf_dup(struct seg *seg, struct seg *newseg);
62 62 static int segnf_unmap(struct seg *seg, caddr_t addr, size_t len);
63 63 static void segnf_free(struct seg *seg);
64 64 static faultcode_t segnf_nomap(void);
65 65 static int segnf_setprot(struct seg *seg, caddr_t addr,
66 66 size_t len, uint_t prot);
67 67 static int segnf_checkprot(struct seg *seg, caddr_t addr,
68 68 size_t len, uint_t prot);
69 69 static int segnf_nop(void);
70 70 static int segnf_getprot(struct seg *seg, caddr_t addr,
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71 71 size_t len, uint_t *protv);
72 72 static u_offset_t segnf_getoffset(struct seg *seg, caddr_t addr);
73 73 static int segnf_gettype(struct seg *seg, caddr_t addr);
74 74 static int segnf_getvp(struct seg *seg, caddr_t addr, struct vnode **vpp);
75 75 static void segnf_dump(struct seg *seg);
76 76 static int segnf_pagelock(struct seg *seg, caddr_t addr, size_t len,
77 77 struct page ***ppp, enum lock_type type, enum seg_rw rw);
78 78 static int segnf_setpagesize(struct seg *seg, caddr_t addr, size_t len,
79 79 uint_t szc);
80 80 static int segnf_getmemid(struct seg *seg, caddr_t addr, memid_t *memidp);
81 -static lgrp_mem_policy_info_t *segnf_getpolicy(struct seg *seg,
82 - caddr_t addr);
83 81
84 82
85 83 struct seg_ops segnf_ops = {
86 84 .dup = segnf_dup,
87 85 .unmap = segnf_unmap,
88 86 .free = segnf_free,
89 87 .fault = (faultcode_t (*)(struct hat *, struct seg *, caddr_t,
90 88 size_t, enum fault_type, enum seg_rw))segnf_nomap,
91 89 .faulta = (faultcode_t (*)(struct seg *, caddr_t)) segnf_nomap,
92 90 .setprot = segnf_setprot,
93 91 .checkprot = segnf_checkprot,
94 92 .sync = (int (*)(struct seg *, caddr_t, size_t, int, uint_t))
95 93 segnf_nop,
96 94 .incore = (size_t (*)(struct seg *, caddr_t, size_t, char *))
97 95 segnf_nop,
98 96 .lockop = (int (*)(struct seg *, caddr_t, size_t, int, int,
99 97 ulong_t *, size_t))segnf_nop,
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100 98 .getprot = segnf_getprot,
101 99 .getoffset = segnf_getoffset,
102 100 .gettype = segnf_gettype,
103 101 .getvp = segnf_getvp,
104 102 .advise = (int (*)(struct seg *, caddr_t, size_t, uint_t))
105 103 segnf_nop,
106 104 .dump = segnf_dump,
107 105 .pagelock = segnf_pagelock,
108 106 .setpagesize = segnf_setpagesize,
109 107 .getmemid = segnf_getmemid,
110 - .getpolicy = segnf_getpolicy,
111 108 };
112 109
113 110 /*
114 111 * vnode and page for the page of zeros we use for the nf mappings.
115 112 */
116 113 static kmutex_t segnf_lock;
117 114 static struct vnode nfvp;
118 115 static struct page **nfpp;
119 116
120 117 #define addr_to_vcolor(addr) \
121 118 (shm_alignment) ? \
122 119 ((int)(((uintptr_t)(addr) & (shm_alignment - 1)) >> PAGESHIFT)) : 0
123 120
124 121 /*
125 122 * We try to limit the number of Non-fault segments created.
126 123 * Non fault segments are created to optimize sparc V9 code which uses
127 124 * the sparc nonfaulting load ASI (ASI_PRIMARY_NOFAULT).
128 125 *
129 126 * There are several reasons why creating too many non-fault segments
130 127 * could cause problems.
131 128 *
132 129 * First, excessive allocation of kernel resources for the seg
133 130 * structures and the HAT data to map the zero pages.
134 131 *
135 132 * Secondly, creating nofault segments actually uses up user virtual
136 133 * address space. This makes it unavailable for subsequent mmap(0, ...)
137 134 * calls which use as_gap() to find empty va regions. Creation of too
138 135 * many nofault segments could thus interfere with the ability of the
139 136 * runtime linker to load a shared object.
140 137 */
141 138 #define MAXSEGFORNF (10000)
142 139 #define MAXNFSEARCH (5)
143 140
144 141
145 142 /*
146 143 * Must be called from startup()
147 144 */
148 145 void
149 146 segnf_init()
150 147 {
151 148 mutex_init(&segnf_lock, NULL, MUTEX_DEFAULT, NULL);
152 149 }
153 150
154 151
155 152 /*
156 153 * Create a no-fault segment.
157 154 *
158 155 * The no-fault segment is not technically necessary, as the code in
159 156 * nfload() in trap.c will emulate the SPARC instruction and load
160 157 * a value of zero in the destination register.
161 158 *
162 159 * However, this code tries to put a page of zero's at the nofault address
163 160 * so that subsequent non-faulting loads to the same page will not
164 161 * trap with a tlb miss.
165 162 *
166 163 * In order to help limit the number of segments we merge adjacent nofault
167 164 * segments into a single segment. If we get a large number of segments
168 165 * we'll also try to delete a random other nf segment.
169 166 */
170 167 /* ARGSUSED */
171 168 int
172 169 segnf_create(struct seg *seg, void *argsp)
173 170 {
174 171 uint_t prot;
175 172 pgcnt_t vacpgs;
176 173 u_offset_t off = 0;
177 174 caddr_t vaddr = NULL;
178 175 int i, color;
179 176 struct seg *s1;
180 177 struct seg *s2;
181 178 size_t size;
182 179 struct as *as = seg->s_as;
183 180
184 181 ASSERT(as && AS_WRITE_HELD(as, &as->a_lock));
185 182
186 183 /*
187 184 * Need a page per virtual color or just 1 if no vac.
188 185 */
189 186 mutex_enter(&segnf_lock);
190 187 if (nfpp == NULL) {
191 188 struct seg kseg;
192 189
193 190 vacpgs = 1;
194 191 if (shm_alignment > PAGESIZE) {
195 192 vacpgs = shm_alignment >> PAGESHIFT;
196 193 }
197 194
198 195 nfpp = kmem_alloc(sizeof (*nfpp) * vacpgs, KM_SLEEP);
199 196
200 197 kseg.s_as = &kas;
201 198 for (i = 0; i < vacpgs; i++, off += PAGESIZE,
202 199 vaddr += PAGESIZE) {
203 200 nfpp[i] = page_create_va(&nfvp, off, PAGESIZE,
204 201 PG_WAIT | PG_NORELOC, &kseg, vaddr);
205 202 page_io_unlock(nfpp[i]);
206 203 page_downgrade(nfpp[i]);
207 204 pagezero(nfpp[i], 0, PAGESIZE);
208 205 }
209 206 }
210 207 mutex_exit(&segnf_lock);
211 208
212 209 hat_map(as->a_hat, seg->s_base, seg->s_size, HAT_MAP);
213 210
214 211 /*
215 212 * s_data can't be NULL because of ASSERTS in the common vm code.
216 213 */
217 214 seg->s_ops = &segnf_ops;
218 215 seg->s_data = seg;
219 216 seg->s_flags |= S_PURGE;
220 217
221 218 mutex_enter(&as->a_contents);
222 219 as->a_flags |= AS_NEEDSPURGE;
223 220 mutex_exit(&as->a_contents);
224 221
225 222 prot = PROT_READ;
226 223 color = addr_to_vcolor(seg->s_base);
227 224 if (as != &kas)
228 225 prot |= PROT_USER;
229 226 hat_memload(as->a_hat, seg->s_base, nfpp[color],
230 227 prot | HAT_NOFAULT, HAT_LOAD);
231 228
232 229 /*
233 230 * At this point see if we can concatenate a segment to
234 231 * a non-fault segment immediately before and/or after it.
235 232 */
236 233 if ((s1 = AS_SEGPREV(as, seg)) != NULL &&
237 234 s1->s_ops == &segnf_ops &&
238 235 s1->s_base + s1->s_size == seg->s_base) {
239 236 size = s1->s_size;
240 237 seg_free(s1);
241 238 seg->s_base -= size;
242 239 seg->s_size += size;
243 240 }
244 241
245 242 if ((s2 = AS_SEGNEXT(as, seg)) != NULL &&
246 243 s2->s_ops == &segnf_ops &&
247 244 seg->s_base + seg->s_size == s2->s_base) {
248 245 size = s2->s_size;
249 246 seg_free(s2);
250 247 seg->s_size += size;
251 248 }
252 249
253 250 /*
254 251 * if we already have a lot of segments, try to delete some other
255 252 * nofault segment to reduce the probability of uncontrolled segment
256 253 * creation.
257 254 *
258 255 * the code looks around quickly (no more than MAXNFSEARCH segments
259 256 * each way) for another NF segment and then deletes it.
260 257 */
261 258 if (avl_numnodes(&as->a_segtree) > MAXSEGFORNF) {
262 259 size = 0;
263 260 s2 = NULL;
264 261 s1 = AS_SEGPREV(as, seg);
265 262 while (size++ < MAXNFSEARCH && s1 != NULL) {
266 263 if (s1->s_ops == &segnf_ops)
267 264 s2 = s1;
268 265 s1 = AS_SEGPREV(s1->s_as, seg);
269 266 }
270 267 if (s2 == NULL) {
271 268 s1 = AS_SEGNEXT(as, seg);
272 269 while (size-- > 0 && s1 != NULL) {
273 270 if (s1->s_ops == &segnf_ops)
274 271 s2 = s1;
275 272 s1 = AS_SEGNEXT(as, seg);
276 273 }
277 274 }
278 275 if (s2 != NULL)
279 276 seg_unmap(s2);
280 277 }
281 278
282 279 return (0);
283 280 }
284 281
285 282 /*
286 283 * Never really need "No fault" segments, so they aren't dup'd.
287 284 */
288 285 /* ARGSUSED */
289 286 static int
290 287 segnf_dup(struct seg *seg, struct seg *newseg)
291 288 {
292 289 panic("segnf_dup");
293 290 return (0);
294 291 }
295 292
296 293 /*
297 294 * Split a segment at addr for length len.
298 295 */
299 296 static int
300 297 segnf_unmap(struct seg *seg, caddr_t addr, size_t len)
301 298 {
302 299 ASSERT(seg->s_as && AS_WRITE_HELD(seg->s_as, &seg->s_as->a_lock));
303 300
304 301 /*
305 302 * Check for bad sizes.
306 303 */
307 304 if (addr < seg->s_base || addr + len > seg->s_base + seg->s_size ||
308 305 (len & PAGEOFFSET) || ((uintptr_t)addr & PAGEOFFSET)) {
309 306 cmn_err(CE_PANIC, "segnf_unmap: bad unmap size");
310 307 }
311 308
312 309 /*
313 310 * Unload any hardware translations in the range to be taken out.
314 311 */
315 312 hat_unload(seg->s_as->a_hat, addr, len, HAT_UNLOAD_UNMAP);
316 313
317 314 if (addr == seg->s_base && len == seg->s_size) {
318 315 /*
319 316 * Freeing entire segment.
320 317 */
321 318 seg_free(seg);
322 319 } else if (addr == seg->s_base) {
323 320 /*
324 321 * Freeing the beginning of the segment.
325 322 */
326 323 seg->s_base += len;
327 324 seg->s_size -= len;
328 325 } else if (addr + len == seg->s_base + seg->s_size) {
329 326 /*
330 327 * Freeing the end of the segment.
331 328 */
332 329 seg->s_size -= len;
333 330 } else {
334 331 /*
335 332 * The section to go is in the middle of the segment, so we
336 333 * have to cut it into two segments. We shrink the existing
337 334 * "seg" at the low end, and create "nseg" for the high end.
338 335 */
339 336 caddr_t nbase = addr + len;
340 337 size_t nsize = (seg->s_base + seg->s_size) - nbase;
341 338 struct seg *nseg;
342 339
343 340 /*
344 341 * Trim down "seg" before trying to stick "nseg" into the as.
345 342 */
346 343 seg->s_size = addr - seg->s_base;
347 344 nseg = seg_alloc(seg->s_as, nbase, nsize);
348 345 if (nseg == NULL)
349 346 cmn_err(CE_PANIC, "segnf_unmap: seg_alloc failed");
350 347
351 348 /*
352 349 * s_data can't be NULL because of ASSERTs in common VM code.
353 350 */
354 351 nseg->s_ops = seg->s_ops;
355 352 nseg->s_data = nseg;
356 353 nseg->s_flags |= S_PURGE;
357 354 mutex_enter(&seg->s_as->a_contents);
358 355 seg->s_as->a_flags |= AS_NEEDSPURGE;
359 356 mutex_exit(&seg->s_as->a_contents);
360 357 }
361 358
362 359 return (0);
363 360 }
364 361
365 362 /*
366 363 * Free a segment.
367 364 */
368 365 static void
369 366 segnf_free(struct seg *seg)
370 367 {
371 368 ASSERT(seg->s_as && AS_WRITE_HELD(seg->s_as, &seg->s_as->a_lock));
372 369 }
373 370
374 371 /*
375 372 * No faults allowed on segnf.
376 373 */
377 374 static faultcode_t
378 375 segnf_nomap(void)
379 376 {
380 377 return (FC_NOMAP);
381 378 }
382 379
383 380 /* ARGSUSED */
384 381 static int
385 382 segnf_setprot(struct seg *seg, caddr_t addr, size_t len, uint_t prot)
386 383 {
387 384 ASSERT(seg->s_as && AS_LOCK_HELD(seg->s_as, &seg->s_as->a_lock));
388 385 return (EACCES);
389 386 }
390 387
391 388 /* ARGSUSED */
392 389 static int
393 390 segnf_checkprot(struct seg *seg, caddr_t addr, size_t len, uint_t prot)
394 391 {
395 392 uint_t sprot;
396 393 ASSERT(seg->s_as && AS_LOCK_HELD(seg->s_as, &seg->s_as->a_lock));
397 394
398 395 sprot = seg->s_as == &kas ? PROT_READ : PROT_READ|PROT_USER;
399 396 return ((prot & sprot) == prot ? 0 : EACCES);
400 397 }
401 398
402 399 static int
403 400 segnf_nop(void)
404 401 {
405 402 return (0);
406 403 }
407 404
408 405 static int
409 406 segnf_getprot(struct seg *seg, caddr_t addr, size_t len, uint_t *protv)
410 407 {
411 408 size_t pgno = seg_page(seg, addr + len) - seg_page(seg, addr) + 1;
412 409 size_t p;
413 410 ASSERT(seg->s_as && AS_LOCK_HELD(seg->s_as, &seg->s_as->a_lock));
414 411
415 412 for (p = 0; p < pgno; ++p)
416 413 protv[p] = PROT_READ;
417 414 return (0);
418 415 }
419 416
420 417 /* ARGSUSED */
421 418 static u_offset_t
422 419 segnf_getoffset(struct seg *seg, caddr_t addr)
423 420 {
424 421 ASSERT(seg->s_as && AS_LOCK_HELD(seg->s_as, &seg->s_as->a_lock));
425 422
426 423 return ((u_offset_t)0);
427 424 }
428 425
429 426 /* ARGSUSED */
430 427 static int
431 428 segnf_gettype(struct seg *seg, caddr_t addr)
432 429 {
433 430 ASSERT(seg->s_as && AS_LOCK_HELD(seg->s_as, &seg->s_as->a_lock));
434 431
435 432 return (MAP_SHARED);
436 433 }
437 434
438 435 /* ARGSUSED */
439 436 static int
440 437 segnf_getvp(struct seg *seg, caddr_t addr, struct vnode **vpp)
441 438 {
442 439 ASSERT(seg->s_as && AS_LOCK_HELD(seg->s_as, &seg->s_as->a_lock));
443 440
444 441 *vpp = &nfvp;
445 442 return (0);
446 443 }
447 444
448 445 /*
449 446 * segnf pages are not dumped, so we just return
450 447 */
451 448 /* ARGSUSED */
452 449 static void
453 450 segnf_dump(struct seg *seg)
454 451 {}
455 452
456 453 /*ARGSUSED*/
457 454 static int
458 455 segnf_pagelock(struct seg *seg, caddr_t addr, size_t len,
459 456 struct page ***ppp, enum lock_type type, enum seg_rw rw)
460 457 {
461 458 return (ENOTSUP);
462 459 }
463 460
464 461 /*ARGSUSED*/
465 462 static int
466 463 segnf_setpagesize(struct seg *seg, caddr_t addr, size_t len,
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467 464 uint_t szc)
468 465 {
469 466 return (ENOTSUP);
470 467 }
471 468
472 469 /*ARGSUSED*/
473 470 static int
474 471 segnf_getmemid(struct seg *seg, caddr_t addr, memid_t *memidp)
475 472 {
476 473 return (ENODEV);
477 -}
478 -
479 -/*ARGSUSED*/
480 -static lgrp_mem_policy_info_t *
481 -segnf_getpolicy(struct seg *seg, caddr_t addr)
482 -{
483 - return (NULL);
484 474 }
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