cxgbe/t4_tom: Read the chip's DDP page sizes and save them in a
[freebsd-src.git] / sys / vm / vm_pager.c
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1 /*-
2 * Copyright (c) 1991, 1993
3 * The Regents of the University of California. All rights reserved.
5 * This code is derived from software contributed to Berkeley by
6 * The Mach Operating System project at Carnegie-Mellon University.
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 4. Neither the name of the University nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
32 * from: @(#)vm_pager.c 8.6 (Berkeley) 1/12/94
35 * Copyright (c) 1987, 1990 Carnegie-Mellon University.
36 * All rights reserved.
38 * Authors: Avadis Tevanian, Jr., Michael Wayne Young
40 * Permission to use, copy, modify and distribute this software and
41 * its documentation is hereby granted, provided that both the copyright
42 * notice and this permission notice appear in all copies of the
43 * software, derivative works or modified versions, and any portions
44 * thereof, and that both notices appear in supporting documentation.
46 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
47 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
48 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
50 * Carnegie Mellon requests users of this software to return to
52 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
53 * School of Computer Science
54 * Carnegie Mellon University
55 * Pittsburgh PA 15213-3890
57 * any improvements or extensions that they make and grant Carnegie the
58 * rights to redistribute these changes.
62 * Paging space routine stubs. Emulates a matchmaker-like interface
63 * for builtin pagers.
66 #include <sys/cdefs.h>
67 __FBSDID("$FreeBSD$");
69 #include <sys/param.h>
70 #include <sys/systm.h>
71 #include <sys/kernel.h>
72 #include <sys/vnode.h>
73 #include <sys/bio.h>
74 #include <sys/buf.h>
75 #include <sys/ucred.h>
76 #include <sys/malloc.h>
77 #include <sys/rwlock.h>
79 #include <vm/vm.h>
80 #include <vm/vm_param.h>
81 #include <vm/vm_kern.h>
82 #include <vm/vm_object.h>
83 #include <vm/vm_page.h>
84 #include <vm/vm_pager.h>
85 #include <vm/vm_extern.h>
87 int cluster_pbuf_freecnt = -1; /* unlimited to begin with */
89 struct buf *swbuf;
91 static int dead_pager_getpages(vm_object_t, vm_page_t *, int, int *, int *);
92 static vm_object_t dead_pager_alloc(void *, vm_ooffset_t, vm_prot_t,
93 vm_ooffset_t, struct ucred *);
94 static void dead_pager_putpages(vm_object_t, vm_page_t *, int, int, int *);
95 static boolean_t dead_pager_haspage(vm_object_t, vm_pindex_t, int *, int *);
96 static void dead_pager_dealloc(vm_object_t);
98 static int
99 dead_pager_getpages(vm_object_t obj, vm_page_t *ma, int count, int *rbehind,
100 int *rahead)
103 return (VM_PAGER_FAIL);
106 static vm_object_t
107 dead_pager_alloc(void *handle, vm_ooffset_t size, vm_prot_t prot,
108 vm_ooffset_t off, struct ucred *cred)
110 return NULL;
113 static void
114 dead_pager_putpages(object, m, count, flags, rtvals)
115 vm_object_t object;
116 vm_page_t *m;
117 int count;
118 int flags;
119 int *rtvals;
121 int i;
123 for (i = 0; i < count; i++) {
124 rtvals[i] = VM_PAGER_AGAIN;
128 static int
129 dead_pager_haspage(object, pindex, prev, next)
130 vm_object_t object;
131 vm_pindex_t pindex;
132 int *prev;
133 int *next;
135 if (prev)
136 *prev = 0;
137 if (next)
138 *next = 0;
139 return FALSE;
142 static void
143 dead_pager_dealloc(object)
144 vm_object_t object;
146 return;
149 static struct pagerops deadpagerops = {
150 .pgo_alloc = dead_pager_alloc,
151 .pgo_dealloc = dead_pager_dealloc,
152 .pgo_getpages = dead_pager_getpages,
153 .pgo_putpages = dead_pager_putpages,
154 .pgo_haspage = dead_pager_haspage,
157 struct pagerops *pagertab[] = {
158 &defaultpagerops, /* OBJT_DEFAULT */
159 &swappagerops, /* OBJT_SWAP */
160 &vnodepagerops, /* OBJT_VNODE */
161 &devicepagerops, /* OBJT_DEVICE */
162 &physpagerops, /* OBJT_PHYS */
163 &deadpagerops, /* OBJT_DEAD */
164 &sgpagerops, /* OBJT_SG */
165 &mgtdevicepagerops, /* OBJT_MGTDEVICE */
169 * Kernel address space for mapping pages.
170 * Used by pagers where KVAs are needed for IO.
172 * XXX needs to be large enough to support the number of pending async
173 * cleaning requests (NPENDINGIO == 64) * the maximum swap cluster size
174 * (MAXPHYS == 64k) if you want to get the most efficiency.
176 struct mtx_padalign pbuf_mtx;
177 static TAILQ_HEAD(swqueue, buf) bswlist;
178 static int bswneeded;
179 vm_offset_t swapbkva; /* swap buffers kva */
181 void
182 vm_pager_init()
184 struct pagerops **pgops;
186 TAILQ_INIT(&bswlist);
188 * Initialize known pagers
190 for (pgops = pagertab; pgops < &pagertab[nitems(pagertab)]; pgops++)
191 if ((*pgops)->pgo_init != NULL)
192 (*(*pgops)->pgo_init) ();
195 void
196 vm_pager_bufferinit()
198 struct buf *bp;
199 int i;
201 mtx_init(&pbuf_mtx, "pbuf mutex", NULL, MTX_DEF);
202 bp = swbuf;
204 * Now set up swap and physical I/O buffer headers.
206 for (i = 0; i < nswbuf; i++, bp++) {
207 TAILQ_INSERT_HEAD(&bswlist, bp, b_freelist);
208 BUF_LOCKINIT(bp);
209 LIST_INIT(&bp->b_dep);
210 bp->b_rcred = bp->b_wcred = NOCRED;
211 bp->b_xflags = 0;
214 cluster_pbuf_freecnt = nswbuf / 2;
215 vnode_pbuf_freecnt = nswbuf / 2 + 1;
216 vnode_async_pbuf_freecnt = nswbuf / 2;
220 * Allocate an instance of a pager of the given type.
221 * Size, protection and offset parameters are passed in for pagers that
222 * need to perform page-level validation (e.g. the device pager).
224 vm_object_t
225 vm_pager_allocate(objtype_t type, void *handle, vm_ooffset_t size,
226 vm_prot_t prot, vm_ooffset_t off, struct ucred *cred)
228 vm_object_t ret;
229 struct pagerops *ops;
231 ops = pagertab[type];
232 if (ops)
233 ret = (*ops->pgo_alloc) (handle, size, prot, off, cred);
234 else
235 ret = NULL;
236 return (ret);
240 * The object must be locked.
242 void
243 vm_pager_deallocate(object)
244 vm_object_t object;
247 VM_OBJECT_ASSERT_WLOCKED(object);
248 (*pagertab[object->type]->pgo_dealloc) (object);
251 static void
252 vm_pager_assert_in(vm_object_t object, vm_page_t *m, int count)
254 #ifdef INVARIANTS
256 VM_OBJECT_ASSERT_WLOCKED(object);
257 KASSERT(count > 0, ("%s: 0 count", __func__));
259 * All pages must be busied, not mapped, not fully valid,
260 * not dirty and belong to the proper object.
262 for (int i = 0 ; i < count; i++) {
263 vm_page_assert_xbusied(m[i]);
264 KASSERT(!pmap_page_is_mapped(m[i]),
265 ("%s: page %p is mapped", __func__, m[i]));
266 KASSERT(m[i]->valid != VM_PAGE_BITS_ALL,
267 ("%s: request for a valid page %p", __func__, m[i]));
268 KASSERT(m[i]->dirty == 0,
269 ("%s: page %p is dirty", __func__, m[i]));
270 KASSERT(m[i]->object == object,
271 ("%s: wrong object %p/%p", __func__, object, m[i]->object));
273 #endif
277 * Page in the pages for the object using its associated pager.
278 * The requested page must be fully valid on successful return.
281 vm_pager_get_pages(vm_object_t object, vm_page_t *m, int count, int *rbehind,
282 int *rahead)
284 #ifdef INVARIANTS
285 vm_pindex_t pindex = m[0]->pindex;
286 #endif
287 int r;
289 vm_pager_assert_in(object, m, count);
291 r = (*pagertab[object->type]->pgo_getpages)(object, m, count, rbehind,
292 rahead);
293 if (r != VM_PAGER_OK)
294 return (r);
296 for (int i = 0; i < count; i++) {
298 * If pager has replaced a page, assert that it had
299 * updated the array.
301 KASSERT(m[i] == vm_page_lookup(object, pindex++),
302 ("%s: mismatch page %p pindex %ju", __func__,
303 m[i], (uintmax_t )pindex - 1));
305 * Zero out partially filled data.
307 if (m[i]->valid != VM_PAGE_BITS_ALL)
308 vm_page_zero_invalid(m[i], TRUE);
310 return (VM_PAGER_OK);
314 vm_pager_get_pages_async(vm_object_t object, vm_page_t *m, int count,
315 int *rbehind, int *rahead, pgo_getpages_iodone_t iodone, void *arg)
318 vm_pager_assert_in(object, m, count);
320 return ((*pagertab[object->type]->pgo_getpages_async)(object, m,
321 count, rbehind, rahead, iodone, arg));
325 * vm_pager_put_pages() - inline, see vm/vm_pager.h
326 * vm_pager_has_page() - inline, see vm/vm_pager.h
330 * Search the specified pager object list for an object with the
331 * specified handle. If an object with the specified handle is found,
332 * increase its reference count and return it. Otherwise, return NULL.
334 * The pager object list must be locked.
336 vm_object_t
337 vm_pager_object_lookup(struct pagerlst *pg_list, void *handle)
339 vm_object_t object;
341 TAILQ_FOREACH(object, pg_list, pager_object_list) {
342 if (object->handle == handle) {
343 VM_OBJECT_WLOCK(object);
344 if ((object->flags & OBJ_DEAD) == 0) {
345 vm_object_reference_locked(object);
346 VM_OBJECT_WUNLOCK(object);
347 break;
349 VM_OBJECT_WUNLOCK(object);
352 return (object);
356 * initialize a physical buffer
360 * XXX This probably belongs in vfs_bio.c
362 static void
363 initpbuf(struct buf *bp)
365 KASSERT(bp->b_bufobj == NULL, ("initpbuf with bufobj"));
366 KASSERT(bp->b_vp == NULL, ("initpbuf with vp"));
367 bp->b_rcred = NOCRED;
368 bp->b_wcred = NOCRED;
369 bp->b_qindex = 0; /* On no queue (QUEUE_NONE) */
370 bp->b_kvabase = (caddr_t) (MAXPHYS * (bp - swbuf)) + swapbkva;
371 bp->b_data = bp->b_kvabase;
372 bp->b_kvasize = MAXPHYS;
373 bp->b_flags = 0;
374 bp->b_xflags = 0;
375 bp->b_ioflags = 0;
376 bp->b_iodone = NULL;
377 bp->b_error = 0;
378 BUF_LOCK(bp, LK_EXCLUSIVE, NULL);
382 * allocate a physical buffer
384 * There are a limited number (nswbuf) of physical buffers. We need
385 * to make sure that no single subsystem is able to hog all of them,
386 * so each subsystem implements a counter which is typically initialized
387 * to 1/2 nswbuf. getpbuf() decrements this counter in allocation and
388 * increments it on release, and blocks if the counter hits zero. A
389 * subsystem may initialize the counter to -1 to disable the feature,
390 * but it must still be sure to match up all uses of getpbuf() with
391 * relpbuf() using the same variable.
393 * NOTE: pfreecnt can be NULL, but this 'feature' will be removed
394 * relatively soon when the rest of the subsystems get smart about it. XXX
396 struct buf *
397 getpbuf(int *pfreecnt)
399 struct buf *bp;
401 mtx_lock(&pbuf_mtx);
403 for (;;) {
404 if (pfreecnt) {
405 while (*pfreecnt == 0) {
406 msleep(pfreecnt, &pbuf_mtx, PVM, "wswbuf0", 0);
410 /* get a bp from the swap buffer header pool */
411 if ((bp = TAILQ_FIRST(&bswlist)) != NULL)
412 break;
414 bswneeded = 1;
415 msleep(&bswneeded, &pbuf_mtx, PVM, "wswbuf1", 0);
416 /* loop in case someone else grabbed one */
418 TAILQ_REMOVE(&bswlist, bp, b_freelist);
419 if (pfreecnt)
420 --*pfreecnt;
421 mtx_unlock(&pbuf_mtx);
423 initpbuf(bp);
424 return bp;
428 * allocate a physical buffer, if one is available.
430 * Note that there is no NULL hack here - all subsystems using this
431 * call understand how to use pfreecnt.
433 struct buf *
434 trypbuf(int *pfreecnt)
436 struct buf *bp;
438 mtx_lock(&pbuf_mtx);
439 if (*pfreecnt == 0 || (bp = TAILQ_FIRST(&bswlist)) == NULL) {
440 mtx_unlock(&pbuf_mtx);
441 return NULL;
443 TAILQ_REMOVE(&bswlist, bp, b_freelist);
445 --*pfreecnt;
447 mtx_unlock(&pbuf_mtx);
449 initpbuf(bp);
451 return bp;
455 * release a physical buffer
457 * NOTE: pfreecnt can be NULL, but this 'feature' will be removed
458 * relatively soon when the rest of the subsystems get smart about it. XXX
460 void
461 relpbuf(struct buf *bp, int *pfreecnt)
464 if (bp->b_rcred != NOCRED) {
465 crfree(bp->b_rcred);
466 bp->b_rcred = NOCRED;
468 if (bp->b_wcred != NOCRED) {
469 crfree(bp->b_wcred);
470 bp->b_wcred = NOCRED;
473 KASSERT(bp->b_vp == NULL, ("relpbuf with vp"));
474 KASSERT(bp->b_bufobj == NULL, ("relpbuf with bufobj"));
476 BUF_UNLOCK(bp);
478 mtx_lock(&pbuf_mtx);
479 TAILQ_INSERT_HEAD(&bswlist, bp, b_freelist);
481 if (bswneeded) {
482 bswneeded = 0;
483 wakeup(&bswneeded);
485 if (pfreecnt) {
486 if (++*pfreecnt == 1)
487 wakeup(pfreecnt);
489 mtx_unlock(&pbuf_mtx);
493 * Associate a p-buffer with a vnode.
495 * Also sets B_PAGING flag to indicate that vnode is not fully associated
496 * with the buffer. i.e. the bp has not been linked into the vnode or
497 * ref-counted.
499 void
500 pbgetvp(struct vnode *vp, struct buf *bp)
503 KASSERT(bp->b_vp == NULL, ("pbgetvp: not free"));
504 KASSERT(bp->b_bufobj == NULL, ("pbgetvp: not free (bufobj)"));
506 bp->b_vp = vp;
507 bp->b_flags |= B_PAGING;
508 bp->b_bufobj = &vp->v_bufobj;
512 * Associate a p-buffer with a vnode.
514 * Also sets B_PAGING flag to indicate that vnode is not fully associated
515 * with the buffer. i.e. the bp has not been linked into the vnode or
516 * ref-counted.
518 void
519 pbgetbo(struct bufobj *bo, struct buf *bp)
522 KASSERT(bp->b_vp == NULL, ("pbgetbo: not free (vnode)"));
523 KASSERT(bp->b_bufobj == NULL, ("pbgetbo: not free (bufobj)"));
525 bp->b_flags |= B_PAGING;
526 bp->b_bufobj = bo;
530 * Disassociate a p-buffer from a vnode.
532 void
533 pbrelvp(struct buf *bp)
536 KASSERT(bp->b_vp != NULL, ("pbrelvp: NULL"));
537 KASSERT(bp->b_bufobj != NULL, ("pbrelvp: NULL bufobj"));
538 KASSERT((bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) == 0,
539 ("pbrelvp: pager buf on vnode list."));
541 bp->b_vp = NULL;
542 bp->b_bufobj = NULL;
543 bp->b_flags &= ~B_PAGING;
547 * Disassociate a p-buffer from a bufobj.
549 void
550 pbrelbo(struct buf *bp)
553 KASSERT(bp->b_vp == NULL, ("pbrelbo: vnode"));
554 KASSERT(bp->b_bufobj != NULL, ("pbrelbo: NULL bufobj"));
555 KASSERT((bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) == 0,
556 ("pbrelbo: pager buf on vnode list."));
558 bp->b_bufobj = NULL;
559 bp->b_flags &= ~B_PAGING;