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1.1 root 1: /*
2: * Copyright (c) 1990 University of Utah.
3: * Copyright (c) 1991 The Regents of the University of California.
4: * All rights reserved.
5: *
6: * This code is derived from software contributed to Berkeley by
7: * the Systems Programming Group of the University of Utah Computer
8: * Science Department.
9: *
10: * Redistribution and use in source and binary forms, with or without
11: * modification, are permitted provided that the following conditions
12: * are met:
13: * 1. Redistributions of source code must retain the above copyright
14: * notice, this list of conditions and the following disclaimer.
15: * 2. Redistributions in binary form must reproduce the above copyright
16: * notice, this list of conditions and the following disclaimer in the
17: * documentation and/or other materials provided with the distribution.
18: * 3. All advertising materials mentioning features or use of this software
19: * must display the following acknowledgement:
20: * This product includes software developed by the University of
21: * California, Berkeley and its contributors.
22: * 4. Neither the name of the University nor the names of its contributors
23: * may be used to endorse or promote products derived from this software
24: * without specific prior written permission.
25: *
26: * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27: * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28: * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29: * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30: * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31: * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32: * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33: * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34: * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35: * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36: * SUCH DAMAGE.
37: *
38: * from: Utah $Hdr: swap_pager.c 1.4 91/04/30$
39: *
1.1.1.5 ! root 40: * from: @(#)swap_pager.c 7.4 (Berkeley) 5/7/91
! 41: * swap_pager.c,v 1.6.2.1 1993/07/31 12:20:49 cgd Exp
1.1 root 42: */
43:
44: /*
45: * Quick hack to page to dedicated partition(s).
46: * TODO:
47: * Add multiprocessor locks
48: * Deal with async writes in a better fashion
49: */
50:
51: #include "swappager.h"
52: #if NSWAPPAGER > 0
53:
54: #include "param.h"
55: #include "proc.h"
56: #include "buf.h"
1.1.1.5 ! root 57: #include "map.h"
1.1 root 58: #include "systm.h"
59: #include "specdev.h"
60: #include "vnode.h"
61: #include "malloc.h"
62: #include "queue.h"
63:
64: #include "vm_param.h"
65: #include "queue.h"
66: #include "lock.h"
67: #include "vm_prot.h"
68: #include "vm_object.h"
69: #include "vm_page.h"
70: #include "vm_pageout.h"
71: #include "swap_pager.h"
72:
73: #define NSWSIZES 16 /* size of swtab */
74: #define NPENDINGIO 64 /* max # of pending cleans */
75: #define MAXDADDRS 64 /* max # of disk addrs for fixed allocations */
76:
77: #ifdef DEBUG
1.1.1.2 root 78: int swpagerdebug = 0 /*0x100*/;
1.1 root 79: #define SDB_FOLLOW 0x001
80: #define SDB_INIT 0x002
81: #define SDB_ALLOC 0x004
82: #define SDB_IO 0x008
83: #define SDB_WRITE 0x010
84: #define SDB_FAIL 0x020
85: #define SDB_ALLOCBLK 0x040
86: #define SDB_FULL 0x080
87: #define SDB_ANOM 0x100
88: #define SDB_ANOMPANIC 0x200
89: #endif
90:
91: struct swpagerclean {
92: queue_head_t spc_list;
93: int spc_flags;
94: struct buf *spc_bp;
95: sw_pager_t spc_swp;
96: vm_offset_t spc_kva;
97: vm_page_t spc_m;
98: } swcleanlist[NPENDINGIO];
99: typedef struct swpagerclean *swp_clean_t;
100:
101: /* spc_flags values */
102: #define SPC_FREE 0x00
103: #define SPC_BUSY 0x01
104: #define SPC_DONE 0x02
105: #define SPC_ERROR 0x04
106: #define SPC_DIRTY 0x08
107:
108: struct swtab {
109: vm_size_t st_osize; /* size of object (bytes) */
110: int st_bsize; /* vs. size of swap block (DEV_BSIZE units) */
111: #ifdef DEBUG
112: u_long st_inuse; /* number in this range in use */
113: u_long st_usecnt; /* total used of this size */
114: #endif
115: } swtab[NSWSIZES+1];
116:
117: #ifdef DEBUG
118: int swap_pager_pendingio; /* max pending async "clean" ops */
119: int swap_pager_poip; /* pageouts in progress */
120: int swap_pager_piip; /* pageins in progress */
121: #endif
122:
123: queue_head_t swap_pager_inuse; /* list of pending page cleans */
124: queue_head_t swap_pager_free; /* list of free pager clean structs */
125: queue_head_t swap_pager_list; /* list of "named" anon regions */
126:
127: void
128: swap_pager_init()
129: {
130: register swp_clean_t spc;
131: register int i, bsize;
132: extern int dmmin, dmmax;
133: int maxbsize;
134:
135: #ifdef DEBUG
136: if (swpagerdebug & (SDB_FOLLOW|SDB_INIT))
137: printf("swpg_init()\n");
138: #endif
139: dfltpagerops = &swappagerops;
140: queue_init(&swap_pager_list);
141:
142: /*
143: * Initialize clean lists
144: */
145: queue_init(&swap_pager_inuse);
146: queue_init(&swap_pager_free);
147: for (i = 0, spc = swcleanlist; i < NPENDINGIO; i++, spc++) {
148: queue_enter(&swap_pager_free, spc, swp_clean_t, spc_list);
149: spc->spc_flags = SPC_FREE;
150: }
151:
152: /*
153: * Calculate the swap allocation constants.
154: */
155: if (dmmin == 0) {
156: dmmin = DMMIN;
157: if (dmmin < CLBYTES/DEV_BSIZE)
158: dmmin = CLBYTES/DEV_BSIZE;
159: }
160: if (dmmax == 0)
161: dmmax = DMMAX;
162:
163: /*
164: * Fill in our table of object size vs. allocation size
165: */
166: bsize = btodb(PAGE_SIZE);
167: if (bsize < dmmin)
168: bsize = dmmin;
169: maxbsize = btodb(sizeof(sw_bm_t) * NBBY * PAGE_SIZE);
170: if (maxbsize > dmmax)
171: maxbsize = dmmax;
172: for (i = 0; i < NSWSIZES; i++) {
173: swtab[i].st_osize = (vm_size_t) (MAXDADDRS * dbtob(bsize));
174: swtab[i].st_bsize = bsize;
175: #ifdef DEBUG
176: if (swpagerdebug & SDB_INIT)
177: printf("swpg_init: ix %d, size %x, bsize %x\n",
178: i, swtab[i].st_osize, swtab[i].st_bsize);
179: #endif
180: if (bsize >= maxbsize)
181: break;
182: bsize *= 2;
183: }
184: swtab[i].st_osize = 0;
185: swtab[i].st_bsize = bsize;
186: }
187:
188: /*
189: * Allocate a pager structure and associated resources.
190: * Note that if we are called from the pageout daemon (handle == NULL)
191: * we should not wait for memory as it could resulting in deadlock.
192: */
193: vm_pager_t
194: swap_pager_alloc(handle, size, prot)
195: caddr_t handle;
196: register vm_size_t size;
197: vm_prot_t prot;
198: {
199: register vm_pager_t pager;
200: register sw_pager_t swp;
201: struct swtab *swt;
202: int waitok;
203:
204: #ifdef DEBUG
205: if (swpagerdebug & (SDB_FOLLOW|SDB_ALLOC))
206: printf("swpg_alloc(%x, %x, %x)\n", handle, size, prot);
207: #endif
208: /*
209: * If this is a "named" anonymous region, look it up and
210: * return the appropriate pager if it exists.
211: */
212: if (handle) {
213: pager = vm_pager_lookup(&swap_pager_list, handle);
214: if (pager != NULL) {
215: /*
216: * Use vm_object_lookup to gain a reference
217: * to the object and also to remove from the
218: * object cache.
219: */
220: if (vm_object_lookup(pager) == NULL)
221: panic("swap_pager_alloc: bad object");
222: return(pager);
223: }
224: }
225: /*
226: * Pager doesn't exist, allocate swap management resources
227: * and initialize.
228: */
229: waitok = handle ? M_WAITOK : M_NOWAIT;
230: pager = (vm_pager_t)malloc(sizeof *pager, M_VMPAGER, waitok);
231: if (pager == NULL)
232: return(NULL);
233: swp = (sw_pager_t)malloc(sizeof *swp, M_VMPGDATA, waitok);
234: if (swp == NULL) {
235: #ifdef DEBUG
236: if (swpagerdebug & SDB_FAIL)
237: printf("swpg_alloc: swpager malloc failed\n");
238: #endif
239: free((caddr_t)pager, M_VMPAGER);
240: return(NULL);
241: }
242: size = round_page(size);
243: for (swt = swtab; swt->st_osize; swt++)
244: if (size <= swt->st_osize)
245: break;
246: #ifdef DEBUG
247: swt->st_inuse++;
248: swt->st_usecnt++;
249: #endif
250: swp->sw_osize = size;
251: swp->sw_bsize = swt->st_bsize;
252: swp->sw_nblocks = (btodb(size) + swp->sw_bsize - 1) / swp->sw_bsize;
253: swp->sw_blocks = (sw_blk_t)
254: malloc(swp->sw_nblocks*sizeof(*swp->sw_blocks),
255: M_VMPGDATA, M_NOWAIT);
256: if (swp->sw_blocks == NULL) {
257: free((caddr_t)swp, M_VMPGDATA);
258: free((caddr_t)pager, M_VMPAGER);
259: #ifdef DEBUG
260: if (swpagerdebug & SDB_FAIL)
261: printf("swpg_alloc: sw_blocks malloc failed\n");
262: swt->st_inuse--;
263: swt->st_usecnt--;
264: #endif
265: return(FALSE);
266: }
267: bzero((caddr_t)swp->sw_blocks,
268: swp->sw_nblocks * sizeof(*swp->sw_blocks));
269: swp->sw_poip = 0;
270: if (handle) {
271: vm_object_t object;
272:
273: swp->sw_flags = SW_NAMED;
274: queue_enter(&swap_pager_list, pager, vm_pager_t, pg_list);
275: /*
276: * Consistant with other pagers: return with object
277: * referenced. Can't do this with handle == NULL
278: * since it might be the pageout daemon calling.
279: */
280: object = vm_object_allocate(size);
281: vm_object_enter(object, pager);
282: vm_object_setpager(object, pager, 0, FALSE);
283: } else {
284: swp->sw_flags = 0;
285: queue_init(&pager->pg_list);
286: }
287: pager->pg_handle = handle;
288: pager->pg_ops = &swappagerops;
289: pager->pg_type = PG_SWAP;
290: pager->pg_data = (caddr_t)swp;
291:
292: #ifdef DEBUG
293: if (swpagerdebug & SDB_ALLOC)
294: printf("swpg_alloc: pg_data %x, %x of %x at %x\n",
295: swp, swp->sw_nblocks, swp->sw_bsize, swp->sw_blocks);
296: #endif
297: return(pager);
298: }
299:
300: void
301: swap_pager_dealloc(pager)
302: vm_pager_t pager;
303: {
304: register int i;
305: register sw_blk_t bp;
306: register sw_pager_t swp;
307: struct swtab *swt;
308: int s;
309:
310: #ifdef DEBUG
311: /* save panic time state */
312: if ((swpagerdebug & SDB_ANOMPANIC) && panicstr)
313: return;
314: if (swpagerdebug & (SDB_FOLLOW|SDB_ALLOC))
315: printf("swpg_dealloc(%x)\n", pager);
316: #endif
317: /*
318: * Remove from list right away so lookups will fail if we
319: * block for pageout completion.
320: */
321: swp = (sw_pager_t) pager->pg_data;
322: if (swp->sw_flags & SW_NAMED) {
323: queue_remove(&swap_pager_list, pager, vm_pager_t, pg_list);
324: swp->sw_flags &= ~SW_NAMED;
325: }
326: #ifdef DEBUG
327: for (swt = swtab; swt->st_osize; swt++)
328: if (swp->sw_osize <= swt->st_osize)
329: break;
330: swt->st_inuse--;
331: #endif
332:
333: /*
334: * Wait for all pageouts to finish and remove
335: * all entries from cleaning list.
336: */
337: s = splbio();
338: while (swp->sw_poip) {
339: swp->sw_flags |= SW_WANTED;
340: assert_wait((int)swp);
341: thread_block();
342: }
343: splx(s);
344: (void) swap_pager_clean(NULL, B_WRITE);
345:
346: /*
347: * Free left over swap blocks
348: */
1.1.1.2 root 349: s = splbio();
1.1 root 350: for (i = 0, bp = swp->sw_blocks; i < swp->sw_nblocks; i++, bp++)
351: if (bp->swb_block) {
352: #ifdef DEBUG
353: if (swpagerdebug & (SDB_ALLOCBLK|SDB_FULL))
354: printf("swpg_dealloc: blk %x\n",
355: bp->swb_block);
356: #endif
1.1.1.5 ! root 357: rmfree(swapmap, swp->sw_bsize, bp->swb_block);
1.1 root 358: }
1.1.1.2 root 359: splx(s);
1.1 root 360: /*
361: * Free swap management resources
362: */
363: free((caddr_t)swp->sw_blocks, M_VMPGDATA);
364: free((caddr_t)swp, M_VMPGDATA);
365: free((caddr_t)pager, M_VMPAGER);
366: }
367:
368: swap_pager_getpage(pager, m, sync)
369: vm_pager_t pager;
370: vm_page_t m;
371: boolean_t sync;
372: {
373: #ifdef DEBUG
374: if (swpagerdebug & SDB_FOLLOW)
375: printf("swpg_getpage(%x, %x, %d)\n", pager, m, sync);
376: #endif
377: return(swap_pager_io((sw_pager_t)pager->pg_data, m, B_READ));
378: }
379:
380: swap_pager_putpage(pager, m, sync)
381: vm_pager_t pager;
382: vm_page_t m;
383: boolean_t sync;
384: {
385: int flags;
386:
387: #ifdef DEBUG
388: if (swpagerdebug & SDB_FOLLOW)
389: printf("swpg_putpage(%x, %x, %d)\n", pager, m, sync);
390: #endif
391: if (pager == NULL) {
392: (void) swap_pager_clean(NULL, B_WRITE);
393: return;
394: }
395: flags = B_WRITE;
396: if (!sync)
397: flags |= B_ASYNC;
398: return(swap_pager_io((sw_pager_t)pager->pg_data, m, flags));
399: }
400:
401: boolean_t
402: swap_pager_haspage(pager, offset)
403: vm_pager_t pager;
404: vm_offset_t offset;
405: {
406: register sw_pager_t swp;
407: register sw_blk_t swb;
408: int ix;
409:
410: #ifdef DEBUG
411: if (swpagerdebug & (SDB_FOLLOW|SDB_ALLOCBLK))
412: printf("swpg_haspage(%x, %x) ", pager, offset);
413: #endif
414: swp = (sw_pager_t) pager->pg_data;
415: ix = offset / dbtob(swp->sw_bsize);
416: if (swp->sw_blocks == NULL || ix >= swp->sw_nblocks) {
417: #ifdef DEBUG
418: if (swpagerdebug & (SDB_FAIL|SDB_FOLLOW|SDB_ALLOCBLK))
419: printf("swpg_haspage: %x bad offset %x, ix %x\n",
420: swp->sw_blocks, offset, ix);
421: #endif
422: return(FALSE);
423: }
424: swb = &swp->sw_blocks[ix];
425: if (swb->swb_block)
426: ix = atop(offset % dbtob(swp->sw_bsize));
427: #ifdef DEBUG
428: if (swpagerdebug & SDB_ALLOCBLK)
429: printf("%x blk %x+%x ", swp->sw_blocks, swb->swb_block, ix);
430: if (swpagerdebug & (SDB_FOLLOW|SDB_ALLOCBLK))
431: printf("-> %c\n",
432: "FT"[swb->swb_block && (swb->swb_mask & (1 << ix))]);
433: #endif
434: if (swb->swb_block && (swb->swb_mask & (1 << ix)))
435: return(TRUE);
436: return(FALSE);
437: }
438:
439: /*
440: * Scaled down version of swap().
441: * Assumes that PAGE_SIZE < MAXPHYS; i.e. only one operation needed.
442: * BOGUS: lower level IO routines expect a KVA so we have to map our
443: * provided physical page into the KVA to keep them happy.
444: */
445: swap_pager_io(swp, m, flags)
446: register sw_pager_t swp;
447: vm_page_t m;
448: int flags;
449: {
450: register struct buf *bp;
451: register sw_blk_t swb;
452: register int s;
453: int ix;
454: boolean_t rv;
455: vm_offset_t kva, off;
456: swp_clean_t spc;
457:
458: #ifdef DEBUG
459: /* save panic time state */
460: if ((swpagerdebug & SDB_ANOMPANIC) && panicstr)
461: return;
462: if (swpagerdebug & (SDB_FOLLOW|SDB_IO))
463: printf("swpg_io(%x, %x, %x)\n", swp, m, flags);
464: #endif
465:
466: /*
467: * For reads (pageins) and synchronous writes, we clean up
468: * all completed async pageouts.
469: */
470: if ((flags & B_ASYNC) == 0) {
471: s = splbio();
472: #ifdef DEBUG
473: /*
474: * Check to see if this page is currently being cleaned.
475: * If it is, we just wait til the operation is done before
476: * continuing.
477: */
478: while (swap_pager_clean(m, flags&B_READ)) {
479: if (swpagerdebug & SDB_ANOM)
480: printf("swap_pager_io: page %x cleaning\n", m);
481:
482: swp->sw_flags |= SW_WANTED;
483: assert_wait((int)swp);
484: thread_block();
485: }
486: #else
487: (void) swap_pager_clean(m, flags&B_READ);
488: #endif
489: splx(s);
490: }
491: /*
492: * For async writes (pageouts), we cleanup completed pageouts so
493: * that all available resources are freed. Also tells us if this
494: * page is already being cleaned. If it is, or no resources
495: * are available, we try again later.
496: */
497: else if (swap_pager_clean(m, B_WRITE) ||
498: queue_empty(&swap_pager_free)) {
499: #ifdef DEBUG
500: if ((swpagerdebug & SDB_ANOM) &&
501: !queue_empty(&swap_pager_free))
502: printf("swap_pager_io: page %x already cleaning\n", m);
503: #endif
504: return(VM_PAGER_FAIL);
505: }
506:
507: /*
508: * Determine swap block and allocate as necessary.
509: */
510: off = m->offset + m->object->paging_offset;
511: ix = off / dbtob(swp->sw_bsize);
512: if (swp->sw_blocks == NULL || ix >= swp->sw_nblocks) {
513: #ifdef DEBUG
514: if (swpagerdebug & SDB_FAIL)
515: printf("swpg_io: bad offset %x+%x(%d) in %x\n",
516: m->offset, m->object->paging_offset,
517: ix, swp->sw_blocks);
518: #endif
519: return(VM_PAGER_FAIL);
520: }
1.1.1.2 root 521: s = splbio();
1.1 root 522: swb = &swp->sw_blocks[ix];
523: off = off % dbtob(swp->sw_bsize);
524: if (flags & B_READ) {
525: if (swb->swb_block == 0 ||
526: (swb->swb_mask & (1 << atop(off))) == 0) {
527: #ifdef DEBUG
528: if (swpagerdebug & (SDB_ALLOCBLK|SDB_FAIL))
529: printf("swpg_io: %x bad read: blk %x+%x, mask %x, off %x+%x\n",
530: swp->sw_blocks,
531: swb->swb_block, atop(off),
532: swb->swb_mask,
533: m->offset, m->object->paging_offset);
534: #endif
535: /* XXX: should we zero page here?? */
1.1.1.2 root 536: splx(s);
1.1 root 537: return(VM_PAGER_FAIL);
538: }
539: } else if (swb->swb_block == 0) {
540: swb->swb_block = rmalloc(swapmap, swp->sw_bsize);
541: if (swb->swb_block == 0) {
542: #ifdef DEBUG
543: if (swpagerdebug & SDB_FAIL)
544: printf("swpg_io: rmalloc of %x failed\n",
545: swp->sw_bsize);
546: #endif
1.1.1.2 root 547: splx(s);
1.1 root 548: return(VM_PAGER_FAIL);
549: }
550: #ifdef DEBUG
551: if (swpagerdebug & (SDB_FULL|SDB_ALLOCBLK))
552: printf("swpg_io: %x alloc blk %x at ix %x\n",
553: swp->sw_blocks, swb->swb_block, ix);
554: #endif
555: }
1.1.1.4 root 556: splx(s);
1.1 root 557:
558: /*
559: * Allocate a kernel virtual address and initialize so that PTE
560: * is available for lower level IO drivers.
561: */
562: kva = vm_pager_map_page(m);
563:
564: /*
565: * Get a swap buffer header and perform the IO
566: */
567: s = splbio();
568: while (bswlist.av_forw == NULL) {
569: #ifdef DEBUG
570: if (swpagerdebug & SDB_ANOM)
571: printf("swap_pager_io: wait on swbuf for %x (%d)\n",
572: m, flags);
573: #endif
574: bswlist.b_flags |= B_WANTED;
1.1.1.5 ! root 575: tsleep((caddr_t)&bswlist, PSWP+1, "swpgio", 0);
1.1 root 576: }
577: bp = bswlist.av_forw;
578: bswlist.av_forw = bp->av_forw;
579: splx(s);
580: bp->b_flags = B_BUSY | (flags & B_READ);
581: bp->b_proc = &proc0; /* XXX (but without B_PHYS set this is ok) */
582: bp->b_un.b_addr = (caddr_t)kva;
1.1.1.5 ! root 583: if (!swb->swb_block)
! 584: panic("swap_pager_io: page to first block\n");
1.1 root 585: bp->b_blkno = swb->swb_block + btodb(off);
586: VHOLD(swapdev_vp);
587: bp->b_vp = swapdev_vp;
588: if (swapdev_vp->v_type == VBLK)
589: bp->b_dev = swapdev_vp->v_rdev;
590: bp->b_bcount = PAGE_SIZE;
591: if ((bp->b_flags & B_READ) == 0)
592: swapdev_vp->v_numoutput++;
593:
594: /*
595: * If this is an async write we set up additional buffer fields
596: * and place a "cleaning" entry on the inuse queue.
597: */
598: if ((flags & (B_READ|B_ASYNC)) == B_ASYNC) {
599: #ifdef DEBUG
600: if (queue_empty(&swap_pager_free))
601: panic("swpg_io: lost spc");
602: #endif
603: queue_remove_first(&swap_pager_free,
604: spc, swp_clean_t, spc_list);
605: #ifdef DEBUG
606: if (spc->spc_flags != SPC_FREE)
607: panic("swpg_io: bad free spc");
608: #endif
609: spc->spc_flags = SPC_BUSY;
610: spc->spc_bp = bp;
611: spc->spc_swp = swp;
612: spc->spc_kva = kva;
613: spc->spc_m = m;
614: bp->b_flags |= B_CALL;
615: bp->b_iodone = swap_pager_iodone;
616: s = splbio();
617: swp->sw_poip++;
618: queue_enter(&swap_pager_inuse, spc, swp_clean_t, spc_list);
619:
620: #ifdef DEBUG
621: swap_pager_poip++;
622: if (swpagerdebug & SDB_WRITE)
623: printf("swpg_io: write: bp=%x swp=%x spc=%x poip=%d\n",
624: bp, swp, spc, swp->sw_poip);
625: if ((swpagerdebug & SDB_ALLOCBLK) &&
626: (swb->swb_mask & (1 << atop(off))) == 0)
627: printf("swpg_io: %x write blk %x+%x\n",
628: swp->sw_blocks, swb->swb_block, atop(off));
629: #endif
630: swb->swb_mask |= (1 << atop(off));
631: splx(s);
632: }
633: #ifdef DEBUG
634: if (swpagerdebug & SDB_IO)
635: printf("swpg_io: IO start: bp %x, db %x, va %x, pa %x\n",
636: bp, swb->swb_block+btodb(off), kva, VM_PAGE_TO_PHYS(m));
637: #endif
638: VOP_STRATEGY(bp);
639: if ((flags & (B_READ|B_ASYNC)) == B_ASYNC) {
640: #ifdef DEBUG
641: if (swpagerdebug & SDB_IO)
642: printf("swpg_io: IO started: bp %x\n", bp);
643: #endif
644: return(VM_PAGER_PEND);
645: }
646: s = splbio();
647: #ifdef DEBUG
648: if (flags & B_READ)
649: swap_pager_piip++;
650: else
651: swap_pager_poip++;
652: #endif
653: while ((bp->b_flags & B_DONE) == 0) {
654: assert_wait((int)bp);
655: thread_block();
656: }
657: #ifdef DEBUG
658: if (flags & B_READ)
659: --swap_pager_piip;
660: else
661: --swap_pager_poip;
662: #endif
663: rv = (bp->b_flags & B_ERROR) ? VM_PAGER_FAIL : VM_PAGER_OK;
1.1.1.3 root 664: bp->b_flags &= ~(B_BUSY|B_WANTED|B_PHYS|B_DIRTY);
1.1 root 665: bp->av_forw = bswlist.av_forw;
666: bswlist.av_forw = bp;
667: if (bp->b_vp)
668: brelvp(bp);
669: if (bswlist.b_flags & B_WANTED) {
670: bswlist.b_flags &= ~B_WANTED;
671: thread_wakeup((int)&bswlist);
672: }
673: if ((flags & B_READ) == 0 && rv == VM_PAGER_OK) {
674: m->clean = TRUE;
675: pmap_clear_modify(VM_PAGE_TO_PHYS(m));
676: }
677: splx(s);
678: #ifdef DEBUG
679: if (swpagerdebug & SDB_IO)
680: printf("swpg_io: IO done: bp %x, rv %d\n", bp, rv);
681: if ((swpagerdebug & SDB_FAIL) && rv == VM_PAGER_FAIL)
682: printf("swpg_io: IO error\n");
683: #endif
684: vm_pager_unmap_page(kva);
685: return(rv);
686: }
687:
688: boolean_t
689: swap_pager_clean(m, rw)
690: vm_page_t m;
691: int rw;
692: {
693: register swp_clean_t spc, tspc;
694: register int s;
695:
696: #ifdef DEBUG
697: /* save panic time state */
698: if ((swpagerdebug & SDB_ANOMPANIC) && panicstr)
699: return;
700: if (swpagerdebug & SDB_FOLLOW)
701: printf("swpg_clean(%x, %d)\n", m, rw);
702: #endif
703: tspc = NULL;
704: for (;;) {
705: /*
706: * Look up and removal from inuse list must be done
707: * at splbio() to avoid conflicts with swap_pager_iodone.
708: */
709: s = splbio();
710: spc = (swp_clean_t) queue_first(&swap_pager_inuse);
711: while (!queue_end(&swap_pager_inuse, (queue_entry_t)spc)) {
712: if ((spc->spc_flags & SPC_DONE) &&
713: swap_pager_finish(spc)) {
714: queue_remove(&swap_pager_inuse, spc,
715: swp_clean_t, spc_list);
716: break;
717: }
718: if (m && m == spc->spc_m) {
719: #ifdef DEBUG
720: if (swpagerdebug & SDB_ANOM)
721: printf("swap_pager_clean: page %x on list, flags %x\n",
722: m, spc->spc_flags);
723: #endif
724: tspc = spc;
725: }
726: spc = (swp_clean_t) queue_next(&spc->spc_list);
727: }
728:
729: /*
730: * No operations done, thats all we can do for now.
731: */
732: if (queue_end(&swap_pager_inuse, (queue_entry_t)spc))
733: break;
734: splx(s);
735:
736: /*
737: * The desired page was found to be busy earlier in
738: * the scan but has since completed.
739: */
740: if (tspc && tspc == spc) {
741: #ifdef DEBUG
742: if (swpagerdebug & SDB_ANOM)
743: printf("swap_pager_clean: page %x done while looking\n",
744: m);
745: #endif
746: tspc = NULL;
747: }
748: spc->spc_flags = SPC_FREE;
749: vm_pager_unmap_page(spc->spc_kva);
750: queue_enter(&swap_pager_free, spc, swp_clean_t, spc_list);
751: #ifdef DEBUG
752: if (swpagerdebug & SDB_WRITE)
753: printf("swpg_clean: free spc %x\n", spc);
754: #endif
755: }
756: #ifdef DEBUG
757: /*
758: * If we found that the desired page is already being cleaned
759: * mark it so that swap_pager_iodone() will not set the clean
760: * flag before the pageout daemon has another chance to clean it.
761: */
762: if (tspc && rw == B_WRITE) {
763: if (swpagerdebug & SDB_ANOM)
764: printf("swap_pager_clean: page %x on clean list\n",
765: tspc);
766: tspc->spc_flags |= SPC_DIRTY;
767: }
768: #endif
769: splx(s);
770:
771: #ifdef DEBUG
772: if (swpagerdebug & SDB_WRITE)
773: printf("swpg_clean: return %d\n", tspc ? TRUE : FALSE);
774: if ((swpagerdebug & SDB_ANOM) && tspc)
775: printf("swpg_clean: %s of cleaning page %x\n",
776: rw == B_READ ? "get" : "put", m);
777: #endif
778: return(tspc ? TRUE : FALSE);
779: }
780:
781: swap_pager_finish(spc)
782: register swp_clean_t spc;
783: {
784: vm_object_t object = spc->spc_m->object;
785:
786: /*
787: * Mark the paging operation as done.
788: * (XXX) If we cannot get the lock, leave it til later.
789: * (XXX) Also we are assuming that an async write is a
790: * pageout operation that has incremented the counter.
791: */
792: if (!vm_object_lock_try(object))
793: return(0);
794:
795: if (--object->paging_in_progress == 0)
796: thread_wakeup((int) object);
797:
798: #ifdef DEBUG
799: /*
800: * XXX: this isn't even close to the right thing to do,
801: * introduces a variety of race conditions.
802: *
803: * If dirty, vm_pageout() has attempted to clean the page
804: * again. In this case we do not do anything as we will
805: * see the page again shortly.
806: */
807: if (spc->spc_flags & SPC_DIRTY) {
808: if (swpagerdebug & SDB_ANOM)
809: printf("swap_pager_finish: page %x dirty again\n",
810: spc->spc_m);
811: spc->spc_m->busy = FALSE;
812: PAGE_WAKEUP(spc->spc_m);
813: vm_object_unlock(object);
814: return(1);
815: }
816: #endif
817: /*
818: * If no error mark as clean and inform the pmap system.
819: * If error, mark as dirty so we will try again.
820: * (XXX could get stuck doing this, should give up after awhile)
821: */
822: if (spc->spc_flags & SPC_ERROR) {
823: printf("swap_pager_finish: clean of page %x failed\n",
824: VM_PAGE_TO_PHYS(spc->spc_m));
825: spc->spc_m->laundry = TRUE;
826: } else {
827: spc->spc_m->clean = TRUE;
828: pmap_clear_modify(VM_PAGE_TO_PHYS(spc->spc_m));
829: }
830: spc->spc_m->busy = FALSE;
831: PAGE_WAKEUP(spc->spc_m);
832:
833: vm_object_unlock(object);
834: return(1);
835: }
836:
837: swap_pager_iodone(bp)
838: register struct buf *bp;
839: {
840: register swp_clean_t spc;
841: daddr_t blk;
842: int s;
843:
844: #ifdef DEBUG
845: /* save panic time state */
846: if ((swpagerdebug & SDB_ANOMPANIC) && panicstr)
847: return;
848: if (swpagerdebug & SDB_FOLLOW)
849: printf("swpg_iodone(%x)\n", bp);
850: #endif
851: s = splbio();
852: spc = (swp_clean_t) queue_first(&swap_pager_inuse);
853: while (!queue_end(&swap_pager_inuse, (queue_entry_t)spc)) {
854: if (spc->spc_bp == bp)
855: break;
856: spc = (swp_clean_t) queue_next(&spc->spc_list);
857: }
858: #ifdef DEBUG
859: if (queue_end(&swap_pager_inuse, (queue_entry_t)spc))
860: panic("swap_pager_iodone: bp not found");
861: #endif
862:
863: spc->spc_flags &= ~SPC_BUSY;
864: spc->spc_flags |= SPC_DONE;
1.1.1.2 root 865: if (bp->b_flags & B_ERROR) {
1.1 root 866: spc->spc_flags |= SPC_ERROR;
1.1.1.2 root 867: printf("error %d blkno %d sz %d ", bp->b_error, bp->b_blkno, bp->b_bcount);
868: }
1.1 root 869: spc->spc_bp = NULL;
870: blk = bp->b_blkno;
871:
872: #ifdef DEBUG
873: --swap_pager_poip;
874: if (swpagerdebug & SDB_WRITE)
875: printf("swpg_iodone: bp=%x swp=%x flags=%x spc=%x poip=%x\n",
876: bp, spc->spc_swp, spc->spc_swp->sw_flags,
877: spc, spc->spc_swp->sw_poip);
878: #endif
879:
880: spc->spc_swp->sw_poip--;
881: if (spc->spc_swp->sw_flags & SW_WANTED) {
882: spc->spc_swp->sw_flags &= ~SW_WANTED;
883: thread_wakeup((int)spc->spc_swp);
884: }
885:
1.1.1.3 root 886: bp->b_flags &= ~(B_BUSY|B_WANTED|B_PHYS|B_DIRTY);
1.1 root 887: bp->av_forw = bswlist.av_forw;
888: bswlist.av_forw = bp;
889: if (bp->b_vp)
890: brelvp(bp);
891: if (bswlist.b_flags & B_WANTED) {
892: bswlist.b_flags &= ~B_WANTED;
893: thread_wakeup((int)&bswlist);
894: }
895: thread_wakeup((int) &vm_pages_needed);
896: splx(s);
897: }
898: #endif
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