File: | kern/vfs_bio.c |
Warning: | line 752, column 2 Access to field 'v_numoutput' results in a dereference of a null pointer (loaded from field 'b_vp') |
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1 | /* $OpenBSD: vfs_bio.c,v 1.208 2021/12/12 09:14:59 visa Exp $ */ | |||
2 | /* $NetBSD: vfs_bio.c,v 1.44 1996/06/11 11:15:36 pk Exp $ */ | |||
3 | ||||
4 | /* | |||
5 | * Copyright (c) 1994 Christopher G. Demetriou | |||
6 | * Copyright (c) 1982, 1986, 1989, 1993 | |||
7 | * The Regents of the University of California. All rights reserved. | |||
8 | * (c) UNIX System Laboratories, Inc. | |||
9 | * All or some portions of this file are derived from material licensed | |||
10 | * to the University of California by American Telephone and Telegraph | |||
11 | * Co. or Unix System Laboratories, Inc. and are reproduced herein with | |||
12 | * the permission of UNIX System Laboratories, Inc. | |||
13 | * | |||
14 | * Redistribution and use in source and binary forms, with or without | |||
15 | * modification, are permitted provided that the following conditions | |||
16 | * are met: | |||
17 | * 1. Redistributions of source code must retain the above copyright | |||
18 | * notice, this list of conditions and the following disclaimer. | |||
19 | * 2. Redistributions in binary form must reproduce the above copyright | |||
20 | * notice, this list of conditions and the following disclaimer in the | |||
21 | * documentation and/or other materials provided with the distribution. | |||
22 | * 3. 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 | * @(#)vfs_bio.c 8.6 (Berkeley) 1/11/94 | |||
39 | */ | |||
40 | ||||
41 | /* | |||
42 | * Some references: | |||
43 | * Bach: The Design of the UNIX Operating System (Prentice Hall, 1986) | |||
44 | * Leffler, et al.: The Design and Implementation of the 4.3BSD | |||
45 | * UNIX Operating System (Addison Welley, 1989) | |||
46 | */ | |||
47 | ||||
48 | #include <sys/param.h> | |||
49 | #include <sys/systm.h> | |||
50 | #include <sys/proc.h> | |||
51 | #include <sys/buf.h> | |||
52 | #include <sys/vnode.h> | |||
53 | #include <sys/mount.h> | |||
54 | #include <sys/malloc.h> | |||
55 | #include <sys/pool.h> | |||
56 | #include <sys/resourcevar.h> | |||
57 | #include <sys/conf.h> | |||
58 | #include <sys/kernel.h> | |||
59 | #include <sys/specdev.h> | |||
60 | #include <sys/tracepoint.h> | |||
61 | #include <uvm/uvm_extern.h> | |||
62 | ||||
63 | /* XXX Should really be in buf.h, but for uvm_constraint_range.. */ | |||
64 | int buf_realloc_pages(struct buf *, struct uvm_constraint_range *, int); | |||
65 | ||||
66 | struct uvm_constraint_range high_constraint; | |||
67 | int fliphigh; | |||
68 | ||||
69 | int nobuffers; | |||
70 | int needbuffer; | |||
71 | struct bio_ops bioops; | |||
72 | ||||
73 | /* private bufcache functions */ | |||
74 | void bufcache_init(void); | |||
75 | void bufcache_adjust(void); | |||
76 | struct buf *bufcache_gethighcleanbuf(void); | |||
77 | struct buf *bufcache_getdmacleanbuf(void); | |||
78 | ||||
79 | /* | |||
80 | * Buffer pool for I/O buffers. | |||
81 | */ | |||
82 | struct pool bufpool; | |||
83 | struct bufhead bufhead = LIST_HEAD_INITIALIZER(bufhead){ ((void *)0) }; | |||
84 | void buf_put(struct buf *); | |||
85 | ||||
86 | struct buf *bio_doread(struct vnode *, daddr_t, int, int); | |||
87 | struct buf *buf_get(struct vnode *, daddr_t, size_t); | |||
88 | void bread_cluster_callback(struct buf *); | |||
89 | int64_t bufcache_recover_dmapages(int discard, int64_t howmany); | |||
90 | ||||
91 | struct bcachestats bcstats; /* counters */ | |||
92 | long lodirtypages; /* dirty page count low water mark */ | |||
93 | long hidirtypages; /* dirty page count high water mark */ | |||
94 | long targetpages; /* target number of pages for cache size */ | |||
95 | long buflowpages; /* smallest size cache allowed */ | |||
96 | long bufhighpages; /* largest size cache allowed */ | |||
97 | long bufbackpages; /* minimum number of pages we shrink when asked to */ | |||
98 | ||||
99 | vsize_t bufkvm; | |||
100 | ||||
101 | struct proc *cleanerproc; | |||
102 | int bd_req; /* Sleep point for cleaner daemon. */ | |||
103 | ||||
104 | #define NUM_CACHES2 2 | |||
105 | #define DMA_CACHE0 0 | |||
106 | struct bufcache cleancache[NUM_CACHES2]; | |||
107 | struct bufqueue dirtyqueue; | |||
108 | ||||
109 | void | |||
110 | buf_put(struct buf *bp) | |||
111 | { | |||
112 | splassert(IPL_BIO)do { if (splassert_ctl > 0) { splassert_check(0x6, __func__ ); } } while (0); | |||
113 | ||||
114 | #ifdef DIAGNOSTIC1 | |||
115 | if (bp->b_pobj != NULL((void *)0)) | |||
116 | KASSERT(bp->b_bufsize > 0)((bp->b_bufsize > 0) ? (void)0 : __assert("diagnostic " , "/usr/src/sys/kern/vfs_bio.c", 116, "bp->b_bufsize > 0" )); | |||
117 | if (ISSET(bp->b_flags, B_DELWRI)((bp->b_flags) & (0x00000080))) | |||
118 | panic("buf_put: releasing dirty buffer"); | |||
119 | if (bp->b_freelist.tqe_next != NOLIST((struct buf *)0x87654321) && | |||
120 | bp->b_freelist.tqe_next != (void *)-1) | |||
121 | panic("buf_put: still on the free list"); | |||
122 | if (bp->b_vnbufs.le_next != NOLIST((struct buf *)0x87654321) && | |||
123 | bp->b_vnbufs.le_next != (void *)-1) | |||
124 | panic("buf_put: still on the vnode list"); | |||
125 | if (!LIST_EMPTY(&bp->b_dep)(((&bp->b_dep)->lh_first) == ((void *)0))) | |||
126 | panic("buf_put: b_dep is not empty"); | |||
127 | #endif | |||
128 | ||||
129 | LIST_REMOVE(bp, b_list)do { if ((bp)->b_list.le_next != ((void *)0)) (bp)->b_list .le_next->b_list.le_prev = (bp)->b_list.le_prev; *(bp)-> b_list.le_prev = (bp)->b_list.le_next; ((bp)->b_list.le_prev ) = ((void *)-1); ((bp)->b_list.le_next) = ((void *)-1); } while (0); | |||
130 | bcstats.numbufs--; | |||
131 | ||||
132 | if (buf_dealloc_mem(bp) != 0) | |||
133 | return; | |||
134 | pool_put(&bufpool, bp); | |||
135 | } | |||
136 | ||||
137 | /* | |||
138 | * Initialize buffers and hash links for buffers. | |||
139 | */ | |||
140 | void | |||
141 | bufinit(void) | |||
142 | { | |||
143 | u_int64_t dmapages; | |||
144 | u_int64_t highpages; | |||
145 | ||||
146 | dmapages = uvm_pagecount(&dma_constraint); | |||
147 | /* take away a guess at how much of this the kernel will consume */ | |||
148 | dmapages -= (atop(physmem)((physmem) >> 12) - atop(uvmexp.free)((uvmexp.free) >> 12)); | |||
149 | ||||
150 | /* See if we have memory above the dma accessible region. */ | |||
151 | high_constraint.ucr_low = dma_constraint.ucr_high; | |||
152 | high_constraint.ucr_high = no_constraint.ucr_high; | |||
153 | if (high_constraint.ucr_low != high_constraint.ucr_high) | |||
154 | high_constraint.ucr_low++; | |||
155 | highpages = uvm_pagecount(&high_constraint); | |||
156 | ||||
157 | /* | |||
158 | * Do we have any significant amount of high memory above | |||
159 | * the DMA region? if so enable moving buffers there, if not, | |||
160 | * don't bother. | |||
161 | */ | |||
162 | if (highpages > dmapages / 4) | |||
163 | fliphigh = 1; | |||
164 | else | |||
165 | fliphigh = 0; | |||
166 | ||||
167 | /* | |||
168 | * If MD code doesn't say otherwise, use up to 10% of DMA'able | |||
169 | * memory for buffers. | |||
170 | */ | |||
171 | if (bufcachepercent == 0) | |||
172 | bufcachepercent = 10; | |||
173 | ||||
174 | /* | |||
175 | * XXX these values and their same use in kern_sysctl | |||
176 | * need to move into buf.h | |||
177 | */ | |||
178 | KASSERT(bufcachepercent <= 90)((bufcachepercent <= 90) ? (void)0 : __assert("diagnostic " , "/usr/src/sys/kern/vfs_bio.c", 178, "bufcachepercent <= 90" )); | |||
179 | KASSERT(bufcachepercent >= 5)((bufcachepercent >= 5) ? (void)0 : __assert("diagnostic " , "/usr/src/sys/kern/vfs_bio.c", 179, "bufcachepercent >= 5" )); | |||
180 | if (bufpages == 0) | |||
181 | bufpages = dmapages * bufcachepercent / 100; | |||
182 | if (bufpages < BCACHE_MIN((4 * (64 * 1024) / (1 << 12)) * 2)) | |||
183 | bufpages = BCACHE_MIN((4 * (64 * 1024) / (1 << 12)) * 2); | |||
184 | KASSERT(bufpages < dmapages)((bufpages < dmapages) ? (void)0 : __assert("diagnostic ", "/usr/src/sys/kern/vfs_bio.c", 184, "bufpages < dmapages" )); | |||
185 | ||||
186 | bufhighpages = bufpages; | |||
187 | ||||
188 | /* | |||
189 | * Set the base backoff level for the buffer cache. We will | |||
190 | * not allow uvm to steal back more than this number of pages. | |||
191 | */ | |||
192 | buflowpages = dmapages * 5 / 100; | |||
193 | if (buflowpages < BCACHE_MIN((4 * (64 * 1024) / (1 << 12)) * 2)) | |||
194 | buflowpages = BCACHE_MIN((4 * (64 * 1024) / (1 << 12)) * 2); | |||
195 | ||||
196 | /* | |||
197 | * set bufbackpages to 100 pages, or 10 percent of the low water mark | |||
198 | * if we don't have that many pages. | |||
199 | */ | |||
200 | ||||
201 | bufbackpages = buflowpages * 10 / 100; | |||
202 | if (bufbackpages > 100) | |||
203 | bufbackpages = 100; | |||
204 | ||||
205 | /* | |||
206 | * If the MD code does not say otherwise, reserve 10% of kva | |||
207 | * space for mapping buffers. | |||
208 | */ | |||
209 | if (bufkvm == 0) | |||
210 | bufkvm = VM_KERNEL_SPACE_SIZE(0xffff800100000000 - 0xffff800000000000) / 10; | |||
211 | ||||
212 | /* | |||
213 | * Don't use more than twice the amount of bufpages for mappings. | |||
214 | * It's twice since we map things sparsely. | |||
215 | */ | |||
216 | if (bufkvm > bufpages * PAGE_SIZE(1 << 12)) | |||
217 | bufkvm = bufpages * PAGE_SIZE(1 << 12); | |||
218 | /* | |||
219 | * Round bufkvm to MAXPHYS because we allocate chunks of va space | |||
220 | * in MAXPHYS chunks. | |||
221 | */ | |||
222 | bufkvm &= ~(MAXPHYS(64 * 1024) - 1); | |||
223 | ||||
224 | pool_init(&bufpool, sizeof(struct buf), 0, IPL_BIO0x6, 0, "bufpl", NULL((void *)0)); | |||
225 | ||||
226 | bufcache_init(); | |||
227 | ||||
228 | /* | |||
229 | * hmm - bufkvm is an argument because it's static, while | |||
230 | * bufpages is global because it can change while running. | |||
231 | */ | |||
232 | buf_mem_init(bufkvm); | |||
233 | ||||
234 | /* | |||
235 | * Set the dirty page high water mark to be less than the low | |||
236 | * water mark for pages in the buffer cache. This ensures we | |||
237 | * can always back off by throwing away clean pages, and give | |||
238 | * ourselves a chance to write out the dirty pages eventually. | |||
239 | */ | |||
240 | hidirtypages = (buflowpages / 4) * 3; | |||
241 | lodirtypages = buflowpages / 2; | |||
242 | ||||
243 | /* | |||
244 | * We are allowed to use up to the reserve. | |||
245 | */ | |||
246 | targetpages = bufpages - RESERVE_PAGES(4 * (64 * 1024) / (1 << 12)); | |||
247 | } | |||
248 | ||||
249 | /* | |||
250 | * Change cachepct | |||
251 | */ | |||
252 | void | |||
253 | bufadjust(int newbufpages) | |||
254 | { | |||
255 | int s; | |||
256 | int64_t npages; | |||
257 | ||||
258 | if (newbufpages < buflowpages) | |||
259 | newbufpages = buflowpages; | |||
260 | ||||
261 | s = splbio()splraise(0x6); | |||
262 | bufpages = newbufpages; | |||
263 | ||||
264 | /* | |||
265 | * We are allowed to use up to the reserve | |||
266 | */ | |||
267 | targetpages = bufpages - RESERVE_PAGES(4 * (64 * 1024) / (1 << 12)); | |||
268 | ||||
269 | npages = bcstats.dmapages - targetpages; | |||
270 | ||||
271 | /* | |||
272 | * Shrinking the cache happens here only if someone has manually | |||
273 | * adjusted bufcachepercent - or the pagedaemon has told us | |||
274 | * to give back memory *now* - so we give it all back. | |||
275 | */ | |||
276 | if (bcstats.dmapages > targetpages) | |||
277 | (void) bufcache_recover_dmapages(0, bcstats.dmapages - targetpages); | |||
278 | bufcache_adjust(); | |||
279 | ||||
280 | /* | |||
281 | * Wake up the cleaner if we have lots of dirty pages, | |||
282 | * or if we are getting low on buffer cache kva. | |||
283 | */ | |||
284 | if ((UNCLEAN_PAGES(bcstats.numbufpages - bcstats.numcleanpages) >= hidirtypages) || | |||
285 | bcstats.kvaslots_avail <= 2 * RESERVE_SLOTS4) | |||
286 | wakeup(&bd_req); | |||
287 | ||||
288 | splx(s)spllower(s); | |||
289 | } | |||
290 | ||||
291 | /* | |||
292 | * Make the buffer cache back off from cachepct. | |||
293 | */ | |||
294 | int | |||
295 | bufbackoff(struct uvm_constraint_range *range, long size) | |||
296 | { | |||
297 | /* | |||
298 | * Back off "size" buffer cache pages. Called by the page | |||
299 | * daemon to consume buffer cache pages rather than scanning. | |||
300 | * | |||
301 | * It returns 0 to the pagedaemon to indicate that it has | |||
302 | * succeeded in freeing enough pages. It returns -1 to | |||
303 | * indicate that it could not and the pagedaemon should take | |||
304 | * other measures. | |||
305 | * | |||
306 | */ | |||
307 | long pdelta, oldbufpages; | |||
308 | ||||
309 | /* | |||
310 | * If we will accept high memory for this backoff | |||
311 | * try to steal it from the high memory buffer cache. | |||
312 | */ | |||
313 | if (range != NULL((void *)0) && range->ucr_high > dma_constraint.ucr_high) { | |||
314 | struct buf *bp; | |||
315 | int64_t start = bcstats.numbufpages, recovered = 0; | |||
316 | int s = splbio()splraise(0x6); | |||
317 | ||||
318 | while ((recovered < size) && | |||
319 | (bp = bufcache_gethighcleanbuf())) { | |||
320 | bufcache_take(bp); | |||
321 | if (bp->b_vp) { | |||
322 | RBT_REMOVE(buf_rb_bufs,buf_rb_bufs_RBT_REMOVE(&bp->b_vp->v_bufs_tree, bp) | |||
323 | &bp->b_vp->v_bufs_tree, bp)buf_rb_bufs_RBT_REMOVE(&bp->b_vp->v_bufs_tree, bp); | |||
324 | brelvp(bp); | |||
325 | } | |||
326 | buf_put(bp); | |||
327 | recovered = start - bcstats.numbufpages; | |||
328 | } | |||
329 | bufcache_adjust(); | |||
330 | splx(s)spllower(s); | |||
331 | ||||
332 | /* If we got enough, return success */ | |||
333 | if (recovered >= size) | |||
334 | return 0; | |||
335 | ||||
336 | /* | |||
337 | * If we needed only memory above DMA, | |||
338 | * return failure | |||
339 | */ | |||
340 | if (range->ucr_low > dma_constraint.ucr_high) | |||
341 | return -1; | |||
342 | ||||
343 | /* Otherwise get the rest from DMA */ | |||
344 | size -= recovered; | |||
345 | } | |||
346 | ||||
347 | /* | |||
348 | * XXX Otherwise do the dma memory cache dance. this needs | |||
349 | * refactoring later to get rid of 'bufpages' | |||
350 | */ | |||
351 | ||||
352 | /* | |||
353 | * Back off by at least bufbackpages. If the page daemon gave us | |||
354 | * a larger size, back off by that much. | |||
355 | */ | |||
356 | pdelta = (size > bufbackpages) ? size : bufbackpages; | |||
357 | ||||
358 | if (bufpages <= buflowpages) | |||
359 | return(-1); | |||
360 | if (bufpages - pdelta < buflowpages) | |||
361 | pdelta = bufpages - buflowpages; | |||
362 | oldbufpages = bufpages; | |||
363 | bufadjust(bufpages - pdelta); | |||
364 | if (oldbufpages - bufpages < size) | |||
365 | return (-1); /* we did not free what we were asked */ | |||
366 | else | |||
367 | return(0); | |||
368 | } | |||
369 | ||||
370 | ||||
371 | /* | |||
372 | * Opportunistically flip a buffer into high memory. Will move the buffer | |||
373 | * if memory is available without sleeping, and return 0, otherwise will | |||
374 | * fail and return -1 with the buffer unchanged. | |||
375 | */ | |||
376 | ||||
377 | int | |||
378 | buf_flip_high(struct buf *bp) | |||
379 | { | |||
380 | int s; | |||
381 | int ret = -1; | |||
382 | ||||
383 | KASSERT(ISSET(bp->b_flags, B_BC))((((bp->b_flags) & (0x02000000))) ? (void)0 : __assert ("diagnostic ", "/usr/src/sys/kern/vfs_bio.c", 383, "ISSET(bp->b_flags, B_BC)" )); | |||
384 | KASSERT(ISSET(bp->b_flags, B_DMA))((((bp->b_flags) & (0x04000000))) ? (void)0 : __assert ("diagnostic ", "/usr/src/sys/kern/vfs_bio.c", 384, "ISSET(bp->b_flags, B_DMA)" )); | |||
385 | KASSERT(bp->cache == DMA_CACHE)((bp->cache == 0) ? (void)0 : __assert("diagnostic ", "/usr/src/sys/kern/vfs_bio.c" , 385, "bp->cache == DMA_CACHE")); | |||
386 | KASSERT(fliphigh)((fliphigh) ? (void)0 : __assert("diagnostic ", "/usr/src/sys/kern/vfs_bio.c" , 386, "fliphigh")); | |||
387 | ||||
388 | /* Attempt to move the buffer to high memory if we can */ | |||
389 | s = splbio()splraise(0x6); | |||
390 | if (buf_realloc_pages(bp, &high_constraint, UVM_PLA_NOWAIT0x0002) == 0) { | |||
391 | KASSERT(!ISSET(bp->b_flags, B_DMA))((!((bp->b_flags) & (0x04000000))) ? (void)0 : __assert ("diagnostic ", "/usr/src/sys/kern/vfs_bio.c", 391, "!ISSET(bp->b_flags, B_DMA)" )); | |||
392 | bcstats.highflips++; | |||
393 | ret = 0; | |||
394 | } else | |||
395 | bcstats.highflops++; | |||
396 | splx(s)spllower(s); | |||
397 | ||||
398 | return ret; | |||
399 | } | |||
400 | ||||
401 | /* | |||
402 | * Flip a buffer to dma reachable memory, when we need it there for | |||
403 | * I/O. This can sleep since it will wait for memory allocation in the | |||
404 | * DMA reachable area since we have to have the buffer there to proceed. | |||
405 | */ | |||
406 | void | |||
407 | buf_flip_dma(struct buf *bp) | |||
408 | { | |||
409 | KASSERT(ISSET(bp->b_flags, B_BC))((((bp->b_flags) & (0x02000000))) ? (void)0 : __assert ("diagnostic ", "/usr/src/sys/kern/vfs_bio.c", 409, "ISSET(bp->b_flags, B_BC)" )); | |||
410 | KASSERT(ISSET(bp->b_flags, B_BUSY))((((bp->b_flags) & (0x00000010))) ? (void)0 : __assert ("diagnostic ", "/usr/src/sys/kern/vfs_bio.c", 410, "ISSET(bp->b_flags, B_BUSY)" )); | |||
411 | KASSERT(bp->cache < NUM_CACHES)((bp->cache < 2) ? (void)0 : __assert("diagnostic ", "/usr/src/sys/kern/vfs_bio.c" , 411, "bp->cache < NUM_CACHES")); | |||
412 | ||||
413 | if (!ISSET(bp->b_flags, B_DMA)((bp->b_flags) & (0x04000000))) { | |||
414 | int s = splbio()splraise(0x6); | |||
415 | ||||
416 | /* move buf to dma reachable memory */ | |||
417 | (void) buf_realloc_pages(bp, &dma_constraint, UVM_PLA_WAITOK0x0001); | |||
418 | KASSERT(ISSET(bp->b_flags, B_DMA))((((bp->b_flags) & (0x04000000))) ? (void)0 : __assert ("diagnostic ", "/usr/src/sys/kern/vfs_bio.c", 418, "ISSET(bp->b_flags, B_DMA)" )); | |||
419 | bcstats.dmaflips++; | |||
420 | splx(s)spllower(s); | |||
421 | } | |||
422 | ||||
423 | if (bp->cache > DMA_CACHE0) { | |||
424 | CLR(bp->b_flags, B_COLD)((bp->b_flags) &= ~(0x01000000)); | |||
425 | CLR(bp->b_flags, B_WARM)((bp->b_flags) &= ~(0x00800000)); | |||
426 | bp->cache = DMA_CACHE0; | |||
427 | } | |||
428 | } | |||
429 | ||||
430 | struct buf * | |||
431 | bio_doread(struct vnode *vp, daddr_t blkno, int size, int async) | |||
432 | { | |||
433 | struct buf *bp; | |||
434 | struct mount *mp; | |||
435 | ||||
436 | bp = getblk(vp, blkno, size, 0, INFSLP0xffffffffffffffffULL); | |||
437 | ||||
438 | /* | |||
439 | * If buffer does not have valid data, start a read. | |||
440 | * Note that if buffer is B_INVAL, getblk() won't return it. | |||
441 | * Therefore, it's valid if its I/O has completed or been delayed. | |||
442 | */ | |||
443 | if (!ISSET(bp->b_flags, (B_DONE | B_DELWRI))((bp->b_flags) & ((0x00000100 | 0x00000080)))) { | |||
444 | SET(bp->b_flags, B_READ | async)((bp->b_flags) |= (0x00008000 | async)); | |||
445 | bcstats.pendingreads++; | |||
446 | bcstats.numreads++; | |||
447 | VOP_STRATEGY(bp->b_vp, bp); | |||
448 | /* Pay for the read. */ | |||
449 | curproc({struct cpu_info *__ci; asm volatile("movq %%gs:%P1,%0" : "=r" (__ci) :"n" (__builtin_offsetof(struct cpu_info, ci_self))); __ci;})->ci_curproc->p_ru.ru_inblock++; /* XXX */ | |||
450 | } else if (async) { | |||
451 | brelse(bp); | |||
452 | } | |||
453 | ||||
454 | mp = vp->v_type == VBLK ? vp->v_specmountpointv_un.vu_specinfo->si_mountpoint : vp->v_mount; | |||
455 | ||||
456 | /* | |||
457 | * Collect statistics on synchronous and asynchronous reads. | |||
458 | * Reads from block devices are charged to their associated | |||
459 | * filesystem (if any). | |||
460 | */ | |||
461 | if (mp != NULL((void *)0)) { | |||
462 | if (async == 0) | |||
463 | mp->mnt_stat.f_syncreads++; | |||
464 | else | |||
465 | mp->mnt_stat.f_asyncreads++; | |||
466 | } | |||
467 | ||||
468 | return (bp); | |||
469 | } | |||
470 | ||||
471 | /* | |||
472 | * Read a disk block. | |||
473 | * This algorithm described in Bach (p.54). | |||
474 | */ | |||
475 | int | |||
476 | bread(struct vnode *vp, daddr_t blkno, int size, struct buf **bpp) | |||
477 | { | |||
478 | struct buf *bp; | |||
479 | ||||
480 | /* Get buffer for block. */ | |||
481 | bp = *bpp = bio_doread(vp, blkno, size, 0); | |||
482 | ||||
483 | /* Wait for the read to complete, and return result. */ | |||
484 | return (biowait(bp)); | |||
485 | } | |||
486 | ||||
487 | /* | |||
488 | * Read-ahead multiple disk blocks. The first is sync, the rest async. | |||
489 | * Trivial modification to the breada algorithm presented in Bach (p.55). | |||
490 | */ | |||
491 | int | |||
492 | breadn(struct vnode *vp, daddr_t blkno, int size, daddr_t rablks[], | |||
493 | int rasizes[], int nrablks, struct buf **bpp) | |||
494 | { | |||
495 | struct buf *bp; | |||
496 | int i; | |||
497 | ||||
498 | bp = *bpp = bio_doread(vp, blkno, size, 0); | |||
499 | ||||
500 | /* | |||
501 | * For each of the read-ahead blocks, start a read, if necessary. | |||
502 | */ | |||
503 | for (i = 0; i < nrablks; i++) { | |||
504 | /* If it's in the cache, just go on to next one. */ | |||
505 | if (incore(vp, rablks[i])) | |||
506 | continue; | |||
507 | ||||
508 | /* Get a buffer for the read-ahead block */ | |||
509 | (void) bio_doread(vp, rablks[i], rasizes[i], B_ASYNC0x00000004); | |||
510 | } | |||
511 | ||||
512 | /* Otherwise, we had to start a read for it; wait until it's valid. */ | |||
513 | return (biowait(bp)); | |||
514 | } | |||
515 | ||||
516 | /* | |||
517 | * Called from interrupt context. | |||
518 | */ | |||
519 | void | |||
520 | bread_cluster_callback(struct buf *bp) | |||
521 | { | |||
522 | struct buf **xbpp = bp->b_saveaddr; | |||
523 | int i; | |||
524 | ||||
525 | if (xbpp[1] != NULL((void *)0)) { | |||
526 | size_t newsize = xbpp[1]->b_bufsize; | |||
527 | ||||
528 | /* | |||
529 | * Shrink this buffer's mapping to only cover its part of | |||
530 | * the total I/O. | |||
531 | */ | |||
532 | buf_fix_mapping(bp, newsize); | |||
533 | bp->b_bcount = newsize; | |||
534 | } | |||
535 | ||||
536 | /* Invalidate read-ahead buffers if read short */ | |||
537 | if (bp->b_resid > 0) { | |||
538 | for (i = 1; xbpp[i] != NULL((void *)0); i++) | |||
539 | continue; | |||
540 | for (i = i - 1; i != 0; i--) { | |||
541 | if (xbpp[i]->b_bufsize <= bp->b_resid) { | |||
542 | bp->b_resid -= xbpp[i]->b_bufsize; | |||
543 | SET(xbpp[i]->b_flags, B_INVAL)((xbpp[i]->b_flags) |= (0x00000800)); | |||
544 | } else if (bp->b_resid > 0) { | |||
545 | bp->b_resid = 0; | |||
546 | SET(xbpp[i]->b_flags, B_INVAL)((xbpp[i]->b_flags) |= (0x00000800)); | |||
547 | } else | |||
548 | break; | |||
549 | } | |||
550 | } | |||
551 | ||||
552 | for (i = 1; xbpp[i] != NULL((void *)0); i++) { | |||
553 | if (ISSET(bp->b_flags, B_ERROR)((bp->b_flags) & (0x00000400))) | |||
554 | SET(xbpp[i]->b_flags, B_INVAL | B_ERROR)((xbpp[i]->b_flags) |= (0x00000800 | 0x00000400)); | |||
555 | /* | |||
556 | * Move the pages from the master buffer's uvm object | |||
557 | * into the individual buffer's uvm objects. | |||
558 | */ | |||
559 | struct uvm_object *newobj = &xbpp[i]->b_uobj; | |||
560 | struct uvm_object *oldobj = &bp->b_uobj; | |||
561 | int page; | |||
562 | ||||
563 | uvm_obj_init(newobj, &bufcache_pager, 1); | |||
564 | for (page = 0; page < atop(xbpp[i]->b_bufsize)((xbpp[i]->b_bufsize) >> 12); page++) { | |||
565 | struct vm_page *pg = uvm_pagelookup(oldobj, | |||
566 | xbpp[i]->b_poffs + ptoa(page)((paddr_t)(page) << 12)); | |||
567 | KASSERT(pg != NULL)((pg != ((void *)0)) ? (void)0 : __assert("diagnostic ", "/usr/src/sys/kern/vfs_bio.c" , 567, "pg != NULL")); | |||
568 | KASSERT(pg->wire_count == 1)((pg->wire_count == 1) ? (void)0 : __assert("diagnostic ", "/usr/src/sys/kern/vfs_bio.c", 568, "pg->wire_count == 1" )); | |||
569 | uvm_pagerealloc(pg, newobj, xbpp[i]->b_poffs + ptoa(page)((paddr_t)(page) << 12)); | |||
570 | } | |||
571 | xbpp[i]->b_pobj = newobj; | |||
572 | ||||
573 | biodone(xbpp[i]); | |||
574 | } | |||
575 | ||||
576 | free(xbpp, M_TEMP127, (i + 1) * sizeof(*xbpp)); | |||
577 | ||||
578 | if (ISSET(bp->b_flags, B_ASYNC)((bp->b_flags) & (0x00000004))) { | |||
579 | brelse(bp); | |||
580 | } else { | |||
581 | CLR(bp->b_flags, B_WANTED)((bp->b_flags) &= ~(0x00010000)); | |||
582 | wakeup(bp); | |||
583 | } | |||
584 | } | |||
585 | ||||
586 | /* | |||
587 | * Read-ahead multiple disk blocks, but make sure only one (big) I/O | |||
588 | * request is sent to the disk. | |||
589 | * XXX This should probably be dropped and breadn should instead be optimized | |||
590 | * XXX to do fewer I/O requests. | |||
591 | */ | |||
592 | int | |||
593 | bread_cluster(struct vnode *vp, daddr_t blkno, int size, struct buf **rbpp) | |||
594 | { | |||
595 | struct buf *bp, **xbpp; | |||
596 | int howmany, maxra, i, inc; | |||
597 | daddr_t sblkno; | |||
598 | ||||
599 | *rbpp = bio_doread(vp, blkno, size, 0); | |||
600 | ||||
601 | /* | |||
602 | * If the buffer is in the cache skip any I/O operation. | |||
603 | */ | |||
604 | if (ISSET((*rbpp)->b_flags, B_CACHE)(((*rbpp)->b_flags) & (0x00000020))) | |||
605 | goto out; | |||
606 | ||||
607 | if (size != round_page(size)(((size) + ((1 << 12) - 1)) & ~((1 << 12) - 1 ))) | |||
608 | goto out; | |||
609 | ||||
610 | if (VOP_BMAP(vp, blkno + 1, NULL((void *)0), &sblkno, &maxra)) | |||
611 | goto out; | |||
612 | ||||
613 | maxra++; | |||
614 | if (sblkno == -1 || maxra < 2) | |||
615 | goto out; | |||
616 | ||||
617 | howmany = MAXPHYS(64 * 1024) / size; | |||
618 | if (howmany > maxra) | |||
619 | howmany = maxra; | |||
620 | ||||
621 | xbpp = mallocarray(howmany + 1, sizeof(*xbpp), M_TEMP127, M_NOWAIT0x0002); | |||
622 | if (xbpp == NULL((void *)0)) | |||
623 | goto out; | |||
624 | ||||
625 | for (i = howmany - 1; i >= 0; i--) { | |||
626 | size_t sz; | |||
627 | ||||
628 | /* | |||
629 | * First buffer allocates big enough size to cover what | |||
630 | * all the other buffers need. | |||
631 | */ | |||
632 | sz = i == 0 ? howmany * size : 0; | |||
633 | ||||
634 | xbpp[i] = buf_get(vp, blkno + i + 1, sz); | |||
635 | if (xbpp[i] == NULL((void *)0)) { | |||
636 | for (++i; i < howmany; i++) { | |||
637 | SET(xbpp[i]->b_flags, B_INVAL)((xbpp[i]->b_flags) |= (0x00000800)); | |||
638 | brelse(xbpp[i]); | |||
639 | } | |||
640 | free(xbpp, M_TEMP127, (howmany + 1) * sizeof(*xbpp)); | |||
641 | goto out; | |||
642 | } | |||
643 | } | |||
644 | ||||
645 | bp = xbpp[0]; | |||
646 | ||||
647 | xbpp[howmany] = NULL((void *)0); | |||
648 | ||||
649 | inc = btodb(size)((size) >> 9); | |||
650 | ||||
651 | for (i = 1; i < howmany; i++) { | |||
652 | bcstats.pendingreads++; | |||
653 | bcstats.numreads++; | |||
654 | /* | |||
655 | * We set B_DMA here because bp above will be B_DMA, | |||
656 | * and we are playing buffer slice-n-dice games from | |||
657 | * the memory allocated in bp. | |||
658 | */ | |||
659 | SET(xbpp[i]->b_flags, B_DMA | B_READ | B_ASYNC)((xbpp[i]->b_flags) |= (0x04000000 | 0x00008000 | 0x00000004 )); | |||
660 | xbpp[i]->b_blkno = sblkno + (i * inc); | |||
661 | xbpp[i]->b_bufsize = xbpp[i]->b_bcount = size; | |||
662 | xbpp[i]->b_data = NULL((void *)0); | |||
663 | xbpp[i]->b_pobj = bp->b_pobj; | |||
664 | xbpp[i]->b_poffs = bp->b_poffs + (i * size); | |||
665 | } | |||
666 | ||||
667 | KASSERT(bp->b_lblkno == blkno + 1)((bp->b_lblkno == blkno + 1) ? (void)0 : __assert("diagnostic " , "/usr/src/sys/kern/vfs_bio.c", 667, "bp->b_lblkno == blkno + 1" )); | |||
668 | KASSERT(bp->b_vp == vp)((bp->b_vp == vp) ? (void)0 : __assert("diagnostic ", "/usr/src/sys/kern/vfs_bio.c" , 668, "bp->b_vp == vp")); | |||
669 | ||||
670 | bp->b_blkno = sblkno; | |||
671 | SET(bp->b_flags, B_READ | B_ASYNC | B_CALL)((bp->b_flags) |= (0x00008000 | 0x00000004 | 0x00000040)); | |||
672 | ||||
673 | bp->b_saveaddr = (void *)xbpp; | |||
674 | bp->b_iodone = bread_cluster_callback; | |||
675 | ||||
676 | bcstats.pendingreads++; | |||
677 | bcstats.numreads++; | |||
678 | VOP_STRATEGY(bp->b_vp, bp); | |||
679 | curproc({struct cpu_info *__ci; asm volatile("movq %%gs:%P1,%0" : "=r" (__ci) :"n" (__builtin_offsetof(struct cpu_info, ci_self))); __ci;})->ci_curproc->p_ru.ru_inblock++; | |||
680 | ||||
681 | out: | |||
682 | return (biowait(*rbpp)); | |||
683 | } | |||
684 | ||||
685 | /* | |||
686 | * Block write. Described in Bach (p.56) | |||
687 | */ | |||
688 | int | |||
689 | bwrite(struct buf *bp) | |||
690 | { | |||
691 | int rv, async, wasdelayed, s; | |||
692 | struct vnode *vp; | |||
693 | struct mount *mp; | |||
694 | ||||
695 | vp = bp->b_vp; | |||
696 | if (vp != NULL((void *)0)) | |||
| ||||
697 | mp = vp->v_type == VBLK? vp->v_specmountpointv_un.vu_specinfo->si_mountpoint : vp->v_mount; | |||
698 | else | |||
699 | mp = NULL((void *)0); | |||
700 | ||||
701 | /* | |||
702 | * Remember buffer type, to switch on it later. If the write was | |||
703 | * synchronous, but the file system was mounted with MNT_ASYNC, | |||
704 | * convert it to a delayed write. | |||
705 | * XXX note that this relies on delayed tape writes being converted | |||
706 | * to async, not sync writes (which is safe, but ugly). | |||
707 | */ | |||
708 | async = ISSET(bp->b_flags, B_ASYNC)((bp->b_flags) & (0x00000004)); | |||
709 | if (!async && mp && ISSET(mp->mnt_flag, MNT_ASYNC)((mp->mnt_flag) & (0x00000040))) { | |||
710 | /* | |||
711 | * Don't convert writes from VND on async filesystems | |||
712 | * that already have delayed writes in the upper layer. | |||
713 | */ | |||
714 | if (!ISSET(bp->b_flags, B_NOCACHE)((bp->b_flags) & (0x00001000))) { | |||
715 | bdwrite(bp); | |||
716 | return (0); | |||
717 | } | |||
718 | } | |||
719 | ||||
720 | /* | |||
721 | * Collect statistics on synchronous and asynchronous writes. | |||
722 | * Writes to block devices are charged to their associated | |||
723 | * filesystem (if any). | |||
724 | */ | |||
725 | if (mp
| |||
726 | if (async) | |||
727 | mp->mnt_stat.f_asyncwrites++; | |||
728 | else | |||
729 | mp->mnt_stat.f_syncwrites++; | |||
730 | } | |||
731 | bcstats.pendingwrites++; | |||
732 | bcstats.numwrites++; | |||
733 | ||||
734 | wasdelayed = ISSET(bp->b_flags, B_DELWRI)((bp->b_flags) & (0x00000080)); | |||
735 | CLR(bp->b_flags, (B_READ | B_DONE | B_ERROR | B_DELWRI))((bp->b_flags) &= ~((0x00008000 | 0x00000100 | 0x00000400 | 0x00000080))); | |||
736 | ||||
737 | s = splbio()splraise(0x6); | |||
738 | ||||
739 | /* | |||
740 | * If not synchronous, pay for the I/O operation and make | |||
741 | * sure the buf is on the correct vnode queue. We have | |||
742 | * to do this now, because if we don't, the vnode may not | |||
743 | * be properly notified that its I/O has completed. | |||
744 | */ | |||
745 | if (wasdelayed) { | |||
746 | reassignbuf(bp); | |||
747 | } else | |||
748 | curproc({struct cpu_info *__ci; asm volatile("movq %%gs:%P1,%0" : "=r" (__ci) :"n" (__builtin_offsetof(struct cpu_info, ci_self))); __ci;})->ci_curproc->p_ru.ru_oublock++; | |||
749 | ||||
750 | ||||
751 | /* Initiate disk write. Make sure the appropriate party is charged. */ | |||
752 | bp->b_vp->v_numoutput++; | |||
| ||||
753 | splx(s)spllower(s); | |||
754 | buf_flip_dma(bp); | |||
755 | SET(bp->b_flags, B_WRITEINPROG)((bp->b_flags) |= (0x00020000)); | |||
756 | VOP_STRATEGY(bp->b_vp, bp); | |||
757 | ||||
758 | /* | |||
759 | * If the queue is above the high water mark, wait till | |||
760 | * the number of outstanding write bufs drops below the low | |||
761 | * water mark. | |||
762 | */ | |||
763 | if (bp->b_bq) | |||
764 | bufq_wait(bp->b_bq); | |||
765 | ||||
766 | if (async) | |||
767 | return (0); | |||
768 | ||||
769 | /* | |||
770 | * If I/O was synchronous, wait for it to complete. | |||
771 | */ | |||
772 | rv = biowait(bp); | |||
773 | ||||
774 | /* Release the buffer. */ | |||
775 | brelse(bp); | |||
776 | ||||
777 | return (rv); | |||
778 | } | |||
779 | ||||
780 | ||||
781 | /* | |||
782 | * Delayed write. | |||
783 | * | |||
784 | * The buffer is marked dirty, but is not queued for I/O. | |||
785 | * This routine should be used when the buffer is expected | |||
786 | * to be modified again soon, typically a small write that | |||
787 | * partially fills a buffer. | |||
788 | * | |||
789 | * NB: magnetic tapes cannot be delayed; they must be | |||
790 | * written in the order that the writes are requested. | |||
791 | * | |||
792 | * Described in Leffler, et al. (pp. 208-213). | |||
793 | */ | |||
794 | void | |||
795 | bdwrite(struct buf *bp) | |||
796 | { | |||
797 | int s; | |||
798 | ||||
799 | /* | |||
800 | * If the block hasn't been seen before: | |||
801 | * (1) Mark it as having been seen, | |||
802 | * (2) Charge for the write. | |||
803 | * (3) Make sure it's on its vnode's correct block list, | |||
804 | * (4) If a buffer is rewritten, move it to end of dirty list | |||
805 | */ | |||
806 | if (!ISSET(bp->b_flags, B_DELWRI)((bp->b_flags) & (0x00000080))) { | |||
807 | SET(bp->b_flags, B_DELWRI)((bp->b_flags) |= (0x00000080)); | |||
808 | s = splbio()splraise(0x6); | |||
809 | buf_flip_dma(bp); | |||
810 | reassignbuf(bp); | |||
811 | splx(s)spllower(s); | |||
812 | curproc({struct cpu_info *__ci; asm volatile("movq %%gs:%P1,%0" : "=r" (__ci) :"n" (__builtin_offsetof(struct cpu_info, ci_self))); __ci;})->ci_curproc->p_ru.ru_oublock++; /* XXX */ | |||
813 | } | |||
814 | ||||
815 | /* The "write" is done, so mark and release the buffer. */ | |||
816 | CLR(bp->b_flags, B_NEEDCOMMIT)((bp->b_flags) &= ~(0x00000002)); | |||
817 | CLR(bp->b_flags, B_NOCACHE)((bp->b_flags) &= ~(0x00001000)); /* Must cache delayed writes */ | |||
818 | SET(bp->b_flags, B_DONE)((bp->b_flags) |= (0x00000100)); | |||
819 | brelse(bp); | |||
820 | } | |||
821 | ||||
822 | /* | |||
823 | * Asynchronous block write; just an asynchronous bwrite(). | |||
824 | */ | |||
825 | void | |||
826 | bawrite(struct buf *bp) | |||
827 | { | |||
828 | ||||
829 | SET(bp->b_flags, B_ASYNC)((bp->b_flags) |= (0x00000004)); | |||
830 | VOP_BWRITE(bp); | |||
831 | } | |||
832 | ||||
833 | /* | |||
834 | * Must be called at splbio() | |||
835 | */ | |||
836 | void | |||
837 | buf_dirty(struct buf *bp) | |||
838 | { | |||
839 | splassert(IPL_BIO)do { if (splassert_ctl > 0) { splassert_check(0x6, __func__ ); } } while (0); | |||
840 | ||||
841 | #ifdef DIAGNOSTIC1 | |||
842 | if (!ISSET(bp->b_flags, B_BUSY)((bp->b_flags) & (0x00000010))) | |||
843 | panic("Trying to dirty buffer on freelist!"); | |||
844 | #endif | |||
845 | ||||
846 | if (ISSET(bp->b_flags, B_DELWRI)((bp->b_flags) & (0x00000080)) == 0) { | |||
847 | SET(bp->b_flags, B_DELWRI)((bp->b_flags) |= (0x00000080)); | |||
848 | buf_flip_dma(bp); | |||
849 | reassignbuf(bp); | |||
850 | } | |||
851 | } | |||
852 | ||||
853 | /* | |||
854 | * Must be called at splbio() | |||
855 | */ | |||
856 | void | |||
857 | buf_undirty(struct buf *bp) | |||
858 | { | |||
859 | splassert(IPL_BIO)do { if (splassert_ctl > 0) { splassert_check(0x6, __func__ ); } } while (0); | |||
860 | ||||
861 | #ifdef DIAGNOSTIC1 | |||
862 | if (!ISSET(bp->b_flags, B_BUSY)((bp->b_flags) & (0x00000010))) | |||
863 | panic("Trying to undirty buffer on freelist!"); | |||
864 | #endif | |||
865 | if (ISSET(bp->b_flags, B_DELWRI)((bp->b_flags) & (0x00000080))) { | |||
866 | CLR(bp->b_flags, B_DELWRI)((bp->b_flags) &= ~(0x00000080)); | |||
867 | reassignbuf(bp); | |||
868 | } | |||
869 | } | |||
870 | ||||
871 | /* | |||
872 | * Release a buffer on to the free lists. | |||
873 | * Described in Bach (p. 46). | |||
874 | */ | |||
875 | void | |||
876 | brelse(struct buf *bp) | |||
877 | { | |||
878 | int s; | |||
879 | ||||
880 | s = splbio()splraise(0x6); | |||
881 | ||||
882 | if (bp->b_data != NULL((void *)0)) | |||
883 | KASSERT(bp->b_bufsize > 0)((bp->b_bufsize > 0) ? (void)0 : __assert("diagnostic " , "/usr/src/sys/kern/vfs_bio.c", 883, "bp->b_bufsize > 0" )); | |||
884 | ||||
885 | /* | |||
886 | * softdep is basically incompatible with not caching buffers | |||
887 | * that have dependencies, so this buffer must be cached | |||
888 | */ | |||
889 | if (LIST_FIRST(&bp->b_dep)((&bp->b_dep)->lh_first) != NULL((void *)0)) | |||
890 | CLR(bp->b_flags, B_NOCACHE)((bp->b_flags) &= ~(0x00001000)); | |||
891 | ||||
892 | /* | |||
893 | * Determine which queue the buffer should be on, then put it there. | |||
894 | */ | |||
895 | ||||
896 | /* If it's not cacheable, or an error, mark it invalid. */ | |||
897 | if (ISSET(bp->b_flags, (B_NOCACHE|B_ERROR))((bp->b_flags) & ((0x00001000|0x00000400)))) | |||
898 | SET(bp->b_flags, B_INVAL)((bp->b_flags) |= (0x00000800)); | |||
899 | /* If it's a write error, also mark the vnode as damaged. */ | |||
900 | if (ISSET(bp->b_flags, B_ERROR)((bp->b_flags) & (0x00000400)) && !ISSET(bp->b_flags, B_READ)((bp->b_flags) & (0x00008000))) { | |||
901 | if (bp->b_vp && bp->b_vp->v_type == VREG) | |||
902 | SET(bp->b_vp->v_bioflag, VBIOERROR)((bp->b_vp->v_bioflag) |= (0x0008)); | |||
903 | } | |||
904 | ||||
905 | if (ISSET(bp->b_flags, B_INVAL)((bp->b_flags) & (0x00000800))) { | |||
906 | /* | |||
907 | * If the buffer is invalid, free it now rather than leaving | |||
908 | * it in a queue and wasting memory. | |||
909 | */ | |||
910 | if (LIST_FIRST(&bp->b_dep)((&bp->b_dep)->lh_first) != NULL((void *)0)) | |||
911 | buf_deallocate(bp); | |||
912 | ||||
913 | if (ISSET(bp->b_flags, B_DELWRI)((bp->b_flags) & (0x00000080))) { | |||
914 | CLR(bp->b_flags, B_DELWRI)((bp->b_flags) &= ~(0x00000080)); | |||
915 | } | |||
916 | ||||
917 | if (bp->b_vp) { | |||
918 | RBT_REMOVE(buf_rb_bufs, &bp->b_vp->v_bufs_tree, bp)buf_rb_bufs_RBT_REMOVE(&bp->b_vp->v_bufs_tree, bp); | |||
919 | brelvp(bp); | |||
920 | } | |||
921 | bp->b_vp = NULL((void *)0); | |||
922 | ||||
923 | /* | |||
924 | * Wake up any processes waiting for _this_ buffer to | |||
925 | * become free. They are not allowed to grab it | |||
926 | * since it will be freed. But the only sleeper is | |||
927 | * getblk and it will restart the operation after | |||
928 | * sleep. | |||
929 | */ | |||
930 | if (ISSET(bp->b_flags, B_WANTED)((bp->b_flags) & (0x00010000))) { | |||
931 | CLR(bp->b_flags, B_WANTED)((bp->b_flags) &= ~(0x00010000)); | |||
932 | wakeup(bp); | |||
933 | } | |||
934 | buf_put(bp); | |||
935 | } else { | |||
936 | /* | |||
937 | * It has valid data. Put it on the end of the appropriate | |||
938 | * queue, so that it'll stick around for as long as possible. | |||
939 | */ | |||
940 | bufcache_release(bp); | |||
941 | ||||
942 | /* Unlock the buffer. */ | |||
943 | CLR(bp->b_flags, (B_AGE | B_ASYNC | B_NOCACHE | B_DEFERRED))((bp->b_flags) &= ~((0x00000001 | 0x00000004 | 0x00001000 | 0x00080000))); | |||
944 | buf_release(bp); | |||
945 | ||||
946 | /* Wake up any processes waiting for _this_ buffer to | |||
947 | * become free. */ | |||
948 | if (ISSET(bp->b_flags, B_WANTED)((bp->b_flags) & (0x00010000))) { | |||
949 | CLR(bp->b_flags, B_WANTED)((bp->b_flags) &= ~(0x00010000)); | |||
950 | wakeup(bp); | |||
951 | } | |||
952 | ||||
953 | if (bcstats.dmapages > targetpages) | |||
954 | (void) bufcache_recover_dmapages(0, | |||
955 | bcstats.dmapages - targetpages); | |||
956 | bufcache_adjust(); | |||
957 | } | |||
958 | ||||
959 | /* Wake up syncer and cleaner processes waiting for buffers. */ | |||
960 | if (nobuffers) { | |||
961 | nobuffers = 0; | |||
962 | wakeup(&nobuffers); | |||
963 | } | |||
964 | ||||
965 | /* Wake up any processes waiting for any buffer to become free. */ | |||
966 | if (needbuffer && bcstats.dmapages < targetpages && | |||
967 | bcstats.kvaslots_avail > RESERVE_SLOTS4) { | |||
968 | needbuffer = 0; | |||
969 | wakeup(&needbuffer); | |||
970 | } | |||
971 | ||||
972 | splx(s)spllower(s); | |||
973 | } | |||
974 | ||||
975 | /* | |||
976 | * Determine if a block is in the cache. Just look on what would be its hash | |||
977 | * chain. If it's there, return a pointer to it, unless it's marked invalid. | |||
978 | */ | |||
979 | struct buf * | |||
980 | incore(struct vnode *vp, daddr_t blkno) | |||
981 | { | |||
982 | struct buf *bp; | |||
983 | struct buf b; | |||
984 | int s; | |||
985 | ||||
986 | s = splbio()splraise(0x6); | |||
987 | ||||
988 | /* Search buf lookup tree */ | |||
989 | b.b_lblkno = blkno; | |||
990 | bp = RBT_FIND(buf_rb_bufs, &vp->v_bufs_tree, &b)buf_rb_bufs_RBT_FIND(&vp->v_bufs_tree, &b); | |||
991 | if (bp != NULL((void *)0) && ISSET(bp->b_flags, B_INVAL)((bp->b_flags) & (0x00000800))) | |||
992 | bp = NULL((void *)0); | |||
993 | ||||
994 | splx(s)spllower(s); | |||
995 | return (bp); | |||
996 | } | |||
997 | ||||
998 | /* | |||
999 | * Get a block of requested size that is associated with | |||
1000 | * a given vnode and block offset. If it is found in the | |||
1001 | * block cache, mark it as having been found, make it busy | |||
1002 | * and return it. Otherwise, return an empty block of the | |||
1003 | * correct size. It is up to the caller to ensure that the | |||
1004 | * cached blocks be of the correct size. | |||
1005 | */ | |||
1006 | struct buf * | |||
1007 | getblk(struct vnode *vp, daddr_t blkno, int size, int slpflag, | |||
1008 | uint64_t slptimeo) | |||
1009 | { | |||
1010 | struct buf *bp; | |||
1011 | struct buf b; | |||
1012 | int s, error; | |||
1013 | ||||
1014 | /* | |||
1015 | * XXX | |||
1016 | * The following is an inlined version of 'incore()', but with | |||
1017 | * the 'invalid' test moved to after the 'busy' test. It's | |||
1018 | * necessary because there are some cases in which the NFS | |||
1019 | * code sets B_INVAL prior to writing data to the server, but | |||
1020 | * in which the buffers actually contain valid data. In this | |||
1021 | * case, we can't allow the system to allocate a new buffer for | |||
1022 | * the block until the write is finished. | |||
1023 | */ | |||
1024 | start: | |||
1025 | s = splbio()splraise(0x6); | |||
1026 | b.b_lblkno = blkno; | |||
1027 | bp = RBT_FIND(buf_rb_bufs, &vp->v_bufs_tree, &b)buf_rb_bufs_RBT_FIND(&vp->v_bufs_tree, &b); | |||
1028 | if (bp != NULL((void *)0)) { | |||
1029 | if (ISSET(bp->b_flags, B_BUSY)((bp->b_flags) & (0x00000010))) { | |||
1030 | SET(bp->b_flags, B_WANTED)((bp->b_flags) |= (0x00010000)); | |||
1031 | error = tsleep_nsec(bp, slpflag | (PRIBIO16 + 1), | |||
1032 | "getblk", slptimeo); | |||
1033 | splx(s)spllower(s); | |||
1034 | if (error) | |||
1035 | return (NULL((void *)0)); | |||
1036 | goto start; | |||
1037 | } | |||
1038 | ||||
1039 | if (!ISSET(bp->b_flags, B_INVAL)((bp->b_flags) & (0x00000800))) { | |||
1040 | bcstats.cachehits++; | |||
1041 | SET(bp->b_flags, B_CACHE)((bp->b_flags) |= (0x00000020)); | |||
1042 | bufcache_take(bp); | |||
1043 | buf_acquire(bp); | |||
1044 | splx(s)spllower(s); | |||
1045 | return (bp); | |||
1046 | } | |||
1047 | } | |||
1048 | splx(s)spllower(s); | |||
1049 | ||||
1050 | if ((bp = buf_get(vp, blkno, size)) == NULL((void *)0)) | |||
1051 | goto start; | |||
1052 | ||||
1053 | return (bp); | |||
1054 | } | |||
1055 | ||||
1056 | /* | |||
1057 | * Get an empty, disassociated buffer of given size. | |||
1058 | */ | |||
1059 | struct buf * | |||
1060 | geteblk(size_t size) | |||
1061 | { | |||
1062 | struct buf *bp; | |||
1063 | ||||
1064 | while ((bp = buf_get(NULL((void *)0), 0, size)) == NULL((void *)0)) | |||
1065 | continue; | |||
1066 | ||||
1067 | return (bp); | |||
1068 | } | |||
1069 | ||||
1070 | /* | |||
1071 | * Allocate a buffer. | |||
1072 | * If vp is given, put it into the buffer cache for that vnode. | |||
1073 | * If size != 0, allocate memory and call buf_map(). | |||
1074 | * If there is already a buffer for the given vnode/blkno, return NULL. | |||
1075 | */ | |||
1076 | struct buf * | |||
1077 | buf_get(struct vnode *vp, daddr_t blkno, size_t size) | |||
1078 | { | |||
1079 | struct buf *bp; | |||
1080 | int poolwait = size == 0 ? PR_NOWAIT0x0002 : PR_WAITOK0x0001; | |||
1081 | int npages; | |||
1082 | int s; | |||
1083 | ||||
1084 | s = splbio()splraise(0x6); | |||
1085 | if (size) { | |||
1086 | /* | |||
1087 | * Wake up the cleaner if we have lots of dirty pages, | |||
1088 | * or if we are getting low on buffer cache kva. | |||
1089 | */ | |||
1090 | if (UNCLEAN_PAGES(bcstats.numbufpages - bcstats.numcleanpages) >= hidirtypages || | |||
1091 | bcstats.kvaslots_avail <= 2 * RESERVE_SLOTS4) | |||
1092 | wakeup(&bd_req); | |||
1093 | ||||
1094 | npages = atop(round_page(size))(((((size) + ((1 << 12) - 1)) & ~((1 << 12) - 1))) >> 12); | |||
1095 | ||||
1096 | /* | |||
1097 | * if our cache has been previously shrunk, | |||
1098 | * allow it to grow again with use up to | |||
1099 | * bufhighpages (cachepercent) | |||
1100 | */ | |||
1101 | if (bufpages < bufhighpages) | |||
1102 | bufadjust(bufhighpages); | |||
1103 | ||||
1104 | /* | |||
1105 | * If we would go over the page target with our | |||
1106 | * new allocation, free enough buffers first | |||
1107 | * to stay at the target with our new allocation. | |||
1108 | */ | |||
1109 | if (bcstats.dmapages + npages > targetpages) { | |||
1110 | (void) bufcache_recover_dmapages(0, npages); | |||
1111 | bufcache_adjust(); | |||
1112 | } | |||
1113 | ||||
1114 | /* | |||
1115 | * If we get here, we tried to free the world down | |||
1116 | * above, and couldn't get down - Wake the cleaner | |||
1117 | * and wait for it to push some buffers out. | |||
1118 | */ | |||
1119 | if ((bcstats.dmapages + npages > targetpages || | |||
1120 | bcstats.kvaslots_avail <= RESERVE_SLOTS4) && | |||
1121 | curproc({struct cpu_info *__ci; asm volatile("movq %%gs:%P1,%0" : "=r" (__ci) :"n" (__builtin_offsetof(struct cpu_info, ci_self))); __ci;})->ci_curproc != syncerproc && curproc({struct cpu_info *__ci; asm volatile("movq %%gs:%P1,%0" : "=r" (__ci) :"n" (__builtin_offsetof(struct cpu_info, ci_self))); __ci;})->ci_curproc != cleanerproc) { | |||
1122 | wakeup(&bd_req); | |||
1123 | needbuffer++; | |||
1124 | tsleep_nsec(&needbuffer, PRIBIO16, "needbuffer", INFSLP0xffffffffffffffffULL); | |||
1125 | splx(s)spllower(s); | |||
1126 | return (NULL((void *)0)); | |||
1127 | } | |||
1128 | if (bcstats.dmapages + npages > bufpages) { | |||
1129 | /* cleaner or syncer */ | |||
1130 | nobuffers = 1; | |||
1131 | tsleep_nsec(&nobuffers, PRIBIO16, "nobuffers", INFSLP0xffffffffffffffffULL); | |||
1132 | splx(s)spllower(s); | |||
1133 | return (NULL((void *)0)); | |||
1134 | } | |||
1135 | } | |||
1136 | ||||
1137 | bp = pool_get(&bufpool, poolwait|PR_ZERO0x0008); | |||
1138 | ||||
1139 | if (bp == NULL((void *)0)) { | |||
1140 | splx(s)spllower(s); | |||
1141 | return (NULL((void *)0)); | |||
1142 | } | |||
1143 | ||||
1144 | bp->b_freelist.tqe_next = NOLIST((struct buf *)0x87654321); | |||
1145 | bp->b_dev = NODEV(dev_t)(-1); | |||
1146 | LIST_INIT(&bp->b_dep)do { ((&bp->b_dep)->lh_first) = ((void *)0); } while (0); | |||
1147 | bp->b_bcount = size; | |||
1148 | ||||
1149 | buf_acquire_nomap(bp); | |||
1150 | ||||
1151 | if (vp != NULL((void *)0)) { | |||
1152 | /* | |||
1153 | * We insert the buffer into the hash with B_BUSY set | |||
1154 | * while we allocate pages for it. This way any getblk | |||
1155 | * that happens while we allocate pages will wait for | |||
1156 | * this buffer instead of starting its own buf_get. | |||
1157 | * | |||
1158 | * But first, we check if someone beat us to it. | |||
1159 | */ | |||
1160 | if (incore(vp, blkno)) { | |||
1161 | pool_put(&bufpool, bp); | |||
1162 | splx(s)spllower(s); | |||
1163 | return (NULL((void *)0)); | |||
1164 | } | |||
1165 | ||||
1166 | bp->b_blkno = bp->b_lblkno = blkno; | |||
1167 | bgetvp(vp, bp); | |||
1168 | if (RBT_INSERT(buf_rb_bufs, &vp->v_bufs_tree, bp)buf_rb_bufs_RBT_INSERT(&vp->v_bufs_tree, bp)) | |||
1169 | panic("buf_get: dup lblk vp %p bp %p", vp, bp); | |||
1170 | } else { | |||
1171 | bp->b_vnbufs.le_next = NOLIST((struct buf *)0x87654321); | |||
1172 | SET(bp->b_flags, B_INVAL)((bp->b_flags) |= (0x00000800)); | |||
1173 | bp->b_vp = NULL((void *)0); | |||
1174 | } | |||
1175 | ||||
1176 | LIST_INSERT_HEAD(&bufhead, bp, b_list)do { if (((bp)->b_list.le_next = (&bufhead)->lh_first ) != ((void *)0)) (&bufhead)->lh_first->b_list.le_prev = &(bp)->b_list.le_next; (&bufhead)->lh_first = (bp); (bp)->b_list.le_prev = &(&bufhead)->lh_first ; } while (0); | |||
1177 | bcstats.numbufs++; | |||
1178 | ||||
1179 | if (size) { | |||
1180 | buf_alloc_pages(bp, round_page(size)(((size) + ((1 << 12) - 1)) & ~((1 << 12) - 1 ))); | |||
1181 | KASSERT(ISSET(bp->b_flags, B_DMA))((((bp->b_flags) & (0x04000000))) ? (void)0 : __assert ("diagnostic ", "/usr/src/sys/kern/vfs_bio.c", 1181, "ISSET(bp->b_flags, B_DMA)" )); | |||
1182 | buf_map(bp); | |||
1183 | } | |||
1184 | ||||
1185 | SET(bp->b_flags, B_BC)((bp->b_flags) |= (0x02000000)); | |||
1186 | splx(s)spllower(s); | |||
1187 | ||||
1188 | return (bp); | |||
1189 | } | |||
1190 | ||||
1191 | /* | |||
1192 | * Buffer cleaning daemon. | |||
1193 | */ | |||
1194 | void | |||
1195 | buf_daemon(void *arg) | |||
1196 | { | |||
1197 | struct buf *bp = NULL((void *)0); | |||
1198 | int s, pushed = 0; | |||
1199 | ||||
1200 | s = splbio()splraise(0x6); | |||
1201 | for (;;) { | |||
1202 | if (bp == NULL((void *)0) || (pushed >= 16 && | |||
1203 | UNCLEAN_PAGES(bcstats.numbufpages - bcstats.numcleanpages) < hidirtypages && | |||
1204 | bcstats.kvaslots_avail > 2 * RESERVE_SLOTS4)){ | |||
1205 | pushed = 0; | |||
1206 | /* | |||
1207 | * Wake up anyone who was waiting for buffers | |||
1208 | * to be released. | |||
1209 | */ | |||
1210 | if (needbuffer) { | |||
1211 | needbuffer = 0; | |||
1212 | wakeup(&needbuffer); | |||
1213 | } | |||
1214 | tsleep_nsec(&bd_req, PRIBIO16 - 7, "cleaner", INFSLP0xffffffffffffffffULL); | |||
1215 | } | |||
1216 | ||||
1217 | while ((bp = bufcache_getdirtybuf())) { | |||
1218 | TRACEPOINT(vfs, cleaner, bp->b_flags, pushed,do { extern struct dt_probe (dt_static_vfs_cleaner); struct dt_probe *dtp = &(dt_static_vfs_cleaner); struct dt_provider *dtpv = dtp->dtp_prov; if (__builtin_expect(((dt_tracing) != 0) , 0) && __builtin_expect(((dtp->dtp_recording) != 0 ), 0)) { dtpv->dtpv_enter(dtpv, dtp, bp->b_flags, pushed , lodirtypages, hidirtypages); } } while (0) | |||
1219 | lodirtypages, hidirtypages)do { extern struct dt_probe (dt_static_vfs_cleaner); struct dt_probe *dtp = &(dt_static_vfs_cleaner); struct dt_provider *dtpv = dtp->dtp_prov; if (__builtin_expect(((dt_tracing) != 0) , 0) && __builtin_expect(((dtp->dtp_recording) != 0 ), 0)) { dtpv->dtpv_enter(dtpv, dtp, bp->b_flags, pushed , lodirtypages, hidirtypages); } } while (0); | |||
1220 | ||||
1221 | if (UNCLEAN_PAGES(bcstats.numbufpages - bcstats.numcleanpages) < lodirtypages && | |||
1222 | bcstats.kvaslots_avail > 2 * RESERVE_SLOTS4 && | |||
1223 | pushed >= 16) | |||
1224 | break; | |||
1225 | ||||
1226 | bufcache_take(bp); | |||
1227 | buf_acquire(bp); | |||
1228 | splx(s)spllower(s); | |||
1229 | ||||
1230 | if (ISSET(bp->b_flags, B_INVAL)((bp->b_flags) & (0x00000800))) { | |||
1231 | brelse(bp); | |||
1232 | s = splbio()splraise(0x6); | |||
1233 | continue; | |||
1234 | } | |||
1235 | #ifdef DIAGNOSTIC1 | |||
1236 | if (!ISSET(bp->b_flags, B_DELWRI)((bp->b_flags) & (0x00000080))) | |||
1237 | panic("Clean buffer on dirty queue"); | |||
1238 | #endif | |||
1239 | if (LIST_FIRST(&bp->b_dep)((&bp->b_dep)->lh_first) != NULL((void *)0) && | |||
1240 | !ISSET(bp->b_flags, B_DEFERRED)((bp->b_flags) & (0x00080000)) && | |||
1241 | buf_countdeps(bp, 0, 0)) { | |||
1242 | SET(bp->b_flags, B_DEFERRED)((bp->b_flags) |= (0x00080000)); | |||
1243 | s = splbio()splraise(0x6); | |||
1244 | bufcache_release(bp); | |||
1245 | buf_release(bp); | |||
1246 | continue; | |||
1247 | } | |||
1248 | ||||
1249 | bawrite(bp); | |||
1250 | pushed++; | |||
1251 | ||||
1252 | sched_pause(yield)do { if (({struct cpu_info *__ci; asm volatile("movq %%gs:%P1,%0" : "=r" (__ci) :"n" (__builtin_offsetof(struct cpu_info, ci_self ))); __ci;})->ci_schedstate.spc_schedflags & 0x0002) yield (); } while (0); | |||
1253 | ||||
1254 | s = splbio()splraise(0x6); | |||
1255 | } | |||
1256 | } | |||
1257 | } | |||
1258 | ||||
1259 | /* | |||
1260 | * Wait for operations on the buffer to complete. | |||
1261 | * When they do, extract and return the I/O's error value. | |||
1262 | */ | |||
1263 | int | |||
1264 | biowait(struct buf *bp) | |||
1265 | { | |||
1266 | int s; | |||
1267 | ||||
1268 | KASSERT(!(bp->b_flags & B_ASYNC))((!(bp->b_flags & 0x00000004)) ? (void)0 : __assert("diagnostic " , "/usr/src/sys/kern/vfs_bio.c", 1268, "!(bp->b_flags & B_ASYNC)" )); | |||
1269 | ||||
1270 | s = splbio()splraise(0x6); | |||
1271 | while (!ISSET(bp->b_flags, B_DONE)((bp->b_flags) & (0x00000100))) | |||
1272 | tsleep_nsec(bp, PRIBIO16 + 1, "biowait", INFSLP0xffffffffffffffffULL); | |||
1273 | splx(s)spllower(s); | |||
1274 | ||||
1275 | /* check for interruption of I/O (e.g. via NFS), then errors. */ | |||
1276 | if (ISSET(bp->b_flags, B_EINTR)((bp->b_flags) & (0x00000200))) { | |||
1277 | CLR(bp->b_flags, B_EINTR)((bp->b_flags) &= ~(0x00000200)); | |||
1278 | return (EINTR4); | |||
1279 | } | |||
1280 | ||||
1281 | if (ISSET(bp->b_flags, B_ERROR)((bp->b_flags) & (0x00000400))) | |||
1282 | return (bp->b_error ? bp->b_error : EIO5); | |||
1283 | else | |||
1284 | return (0); | |||
1285 | } | |||
1286 | ||||
1287 | /* | |||
1288 | * Mark I/O complete on a buffer. | |||
1289 | * | |||
1290 | * If a callback has been requested, e.g. the pageout | |||
1291 | * daemon, do so. Otherwise, awaken waiting processes. | |||
1292 | * | |||
1293 | * [ Leffler, et al., says on p.247: | |||
1294 | * "This routine wakes up the blocked process, frees the buffer | |||
1295 | * for an asynchronous write, or, for a request by the pagedaemon | |||
1296 | * process, invokes a procedure specified in the buffer structure" ] | |||
1297 | * | |||
1298 | * In real life, the pagedaemon (or other system processes) wants | |||
1299 | * to do async stuff to, and doesn't want the buffer brelse()'d. | |||
1300 | * (for swap pager, that puts swap buffers on the free lists (!!!), | |||
1301 | * for the vn device, that puts malloc'd buffers on the free lists!) | |||
1302 | * | |||
1303 | * Must be called at splbio(). | |||
1304 | */ | |||
1305 | void | |||
1306 | biodone(struct buf *bp) | |||
1307 | { | |||
1308 | splassert(IPL_BIO)do { if (splassert_ctl > 0) { splassert_check(0x6, __func__ ); } } while (0); | |||
1309 | ||||
1310 | if (ISSET(bp->b_flags, B_DONE)((bp->b_flags) & (0x00000100))) | |||
1311 | panic("biodone already"); | |||
1312 | SET(bp->b_flags, B_DONE)((bp->b_flags) |= (0x00000100)); /* note that it's done */ | |||
1313 | ||||
1314 | if (bp->b_bq) | |||
1315 | bufq_done(bp->b_bq, bp); | |||
1316 | ||||
1317 | if (LIST_FIRST(&bp->b_dep)((&bp->b_dep)->lh_first) != NULL((void *)0)) | |||
1318 | buf_complete(bp); | |||
1319 | ||||
1320 | if (!ISSET(bp->b_flags, B_READ)((bp->b_flags) & (0x00008000))) { | |||
1321 | CLR(bp->b_flags, B_WRITEINPROG)((bp->b_flags) &= ~(0x00020000)); | |||
1322 | vwakeup(bp->b_vp); | |||
1323 | } | |||
1324 | if (bcstats.numbufs && | |||
1325 | (!(ISSET(bp->b_flags, B_RAW)((bp->b_flags) & (0x00004000)) || ISSET(bp->b_flags, B_PHYS)((bp->b_flags) & (0x00002000))))) { | |||
1326 | if (!ISSET(bp->b_flags, B_READ)((bp->b_flags) & (0x00008000))) { | |||
1327 | bcstats.pendingwrites--; | |||
1328 | } else | |||
1329 | bcstats.pendingreads--; | |||
1330 | } | |||
1331 | if (ISSET(bp->b_flags, B_CALL)((bp->b_flags) & (0x00000040))) { /* if necessary, call out */ | |||
1332 | CLR(bp->b_flags, B_CALL)((bp->b_flags) &= ~(0x00000040)); /* but note callout done */ | |||
1333 | (*bp->b_iodone)(bp); | |||
1334 | } else { | |||
1335 | if (ISSET(bp->b_flags, B_ASYNC)((bp->b_flags) & (0x00000004))) {/* if async, release it */ | |||
1336 | brelse(bp); | |||
1337 | } else { /* or just wakeup the buffer */ | |||
1338 | CLR(bp->b_flags, B_WANTED)((bp->b_flags) &= ~(0x00010000)); | |||
1339 | wakeup(bp); | |||
1340 | } | |||
1341 | } | |||
1342 | } | |||
1343 | ||||
1344 | #ifdef DDB1 | |||
1345 | void bcstats_print(int (*)(const char *, ...) | |||
1346 | __attribute__((__format__(__kprintf__,1,2)))); | |||
1347 | /* | |||
1348 | * bcstats_print: ddb hook to print interesting buffer cache counters | |||
1349 | */ | |||
1350 | void | |||
1351 | bcstats_print( | |||
1352 | int (*pr)(const char *, ...) __attribute__((__format__(__kprintf__,1,2)))) | |||
1353 | { | |||
1354 | (*pr)("Current Buffer Cache status:\n"); | |||
1355 | (*pr)("numbufs %lld busymapped %lld, delwri %lld\n", | |||
1356 | bcstats.numbufs, bcstats.busymapped, bcstats.delwribufs); | |||
1357 | (*pr)("kvaslots %lld avail kva slots %lld\n", | |||
1358 | bcstats.kvaslots, bcstats.kvaslots_avail); | |||
1359 | (*pr)("bufpages %lld, dmapages %lld, dirtypages %lld\n", | |||
1360 | bcstats.numbufpages, bcstats.dmapages, bcstats.numdirtypages); | |||
1361 | (*pr)("pendingreads %lld, pendingwrites %lld\n", | |||
1362 | bcstats.pendingreads, bcstats.pendingwrites); | |||
1363 | (*pr)("highflips %lld, highflops %lld, dmaflips %lld\n", | |||
1364 | bcstats.highflips, bcstats.highflops, bcstats.dmaflips); | |||
1365 | } | |||
1366 | #endif | |||
1367 | ||||
1368 | void | |||
1369 | buf_adjcnt(struct buf *bp, long ncount) | |||
1370 | { | |||
1371 | KASSERT(ncount <= bp->b_bufsize)((ncount <= bp->b_bufsize) ? (void)0 : __assert("diagnostic " , "/usr/src/sys/kern/vfs_bio.c", 1371, "ncount <= bp->b_bufsize" )); | |||
1372 | bp->b_bcount = ncount; | |||
1373 | } | |||
1374 | ||||
1375 | /* bufcache freelist code below */ | |||
1376 | /* | |||
1377 | * Copyright (c) 2014 Ted Unangst <tedu@openbsd.org> | |||
1378 | * | |||
1379 | * Permission to use, copy, modify, and distribute this software for any | |||
1380 | * purpose with or without fee is hereby granted, provided that the above | |||
1381 | * copyright notice and this permission notice appear in all copies. | |||
1382 | * | |||
1383 | * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES | |||
1384 | * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF | |||
1385 | * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR | |||
1386 | * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES | |||
1387 | * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN | |||
1388 | * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF | |||
1389 | * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. | |||
1390 | */ | |||
1391 | ||||
1392 | /* | |||
1393 | * The code below implements a variant of the 2Q buffer cache algorithm by | |||
1394 | * Johnson and Shasha. | |||
1395 | * | |||
1396 | * General Outline | |||
1397 | * We divide the buffer cache into three working sets: current, previous, | |||
1398 | * and long term. Each list is itself LRU and buffers get promoted and moved | |||
1399 | * around between them. A buffer starts its life in the current working set. | |||
1400 | * As time passes and newer buffers push it out, it will turn into the previous | |||
1401 | * working set and is subject to recycling. But if it's accessed again from | |||
1402 | * the previous working set, that's an indication that it's actually in the | |||
1403 | * long term working set, so we promote it there. The separation of current | |||
1404 | * and previous working sets prevents us from promoting a buffer that's only | |||
1405 | * temporarily hot to the long term cache. | |||
1406 | * | |||
1407 | * The objective is to provide scan resistance by making the long term | |||
1408 | * working set ineligible for immediate recycling, even as the current | |||
1409 | * working set is rapidly turned over. | |||
1410 | * | |||
1411 | * Implementation | |||
1412 | * The code below identifies the current, previous, and long term sets as | |||
1413 | * hotqueue, coldqueue, and warmqueue. The hot and warm queues are capped at | |||
1414 | * 1/3 of the total clean pages, after which point they start pushing their | |||
1415 | * oldest buffers into coldqueue. | |||
1416 | * A buf always starts out with neither WARM or COLD flags set (implying HOT). | |||
1417 | * When released, it will be returned to the tail of the hotqueue list. | |||
1418 | * When the hotqueue gets too large, the oldest hot buf will be moved to the | |||
1419 | * coldqueue, with the B_COLD flag set. When a cold buf is released, we set | |||
1420 | * the B_WARM flag and put it onto the warmqueue. Warm bufs are also | |||
1421 | * directly returned to the end of the warmqueue. As with the hotqueue, when | |||
1422 | * the warmqueue grows too large, B_WARM bufs are moved onto the coldqueue. | |||
1423 | * | |||
1424 | * Note that this design does still support large working sets, greater | |||
1425 | * than the cap of hotqueue or warmqueue would imply. The coldqueue is still | |||
1426 | * cached and has no maximum length. The hot and warm queues form a Y feeding | |||
1427 | * into the coldqueue. Moving bufs between queues is constant time, so this | |||
1428 | * design decays to one long warm->cold queue. | |||
1429 | * | |||
1430 | * In the 2Q paper, hotqueue and coldqueue are A1in and A1out. The warmqueue | |||
1431 | * is Am. We always cache pages, as opposed to pointers to pages for A1. | |||
1432 | * | |||
1433 | * This implementation adds support for multiple 2q caches. | |||
1434 | * | |||
1435 | * If we have more than one 2q cache, as bufs fall off the cold queue | |||
1436 | * for recycling, bufs that have been warm before (which retain the | |||
1437 | * B_WARM flag in addition to B_COLD) can be put into the hot queue of | |||
1438 | * a second level 2Q cache. buffers which are only B_COLD are | |||
1439 | * recycled. Bufs falling off the last cache's cold queue are always | |||
1440 | * recycled. | |||
1441 | * | |||
1442 | */ | |||
1443 | ||||
1444 | /* | |||
1445 | * this function is called when a hot or warm queue may have exceeded its | |||
1446 | * size limit. it will move a buf to the coldqueue. | |||
1447 | */ | |||
1448 | int chillbufs(struct | |||
1449 | bufcache *cache, struct bufqueue *queue, int64_t *queuepages); | |||
1450 | ||||
1451 | void | |||
1452 | bufcache_init(void) | |||
1453 | { | |||
1454 | int i; | |||
1455 | ||||
1456 | for (i = 0; i < NUM_CACHES2; i++) { | |||
1457 | TAILQ_INIT(&cleancache[i].hotqueue)do { (&cleancache[i].hotqueue)->tqh_first = ((void *)0 ); (&cleancache[i].hotqueue)->tqh_last = &(&cleancache [i].hotqueue)->tqh_first; } while (0); | |||
1458 | TAILQ_INIT(&cleancache[i].coldqueue)do { (&cleancache[i].coldqueue)->tqh_first = ((void *) 0); (&cleancache[i].coldqueue)->tqh_last = &(& cleancache[i].coldqueue)->tqh_first; } while (0); | |||
1459 | TAILQ_INIT(&cleancache[i].warmqueue)do { (&cleancache[i].warmqueue)->tqh_first = ((void *) 0); (&cleancache[i].warmqueue)->tqh_last = &(& cleancache[i].warmqueue)->tqh_first; } while (0); | |||
1460 | } | |||
1461 | TAILQ_INIT(&dirtyqueue)do { (&dirtyqueue)->tqh_first = ((void *)0); (&dirtyqueue )->tqh_last = &(&dirtyqueue)->tqh_first; } while (0); | |||
1462 | } | |||
1463 | ||||
1464 | /* | |||
1465 | * if the buffer caches have shrunk, we may need to rebalance our queues. | |||
1466 | */ | |||
1467 | void | |||
1468 | bufcache_adjust(void) | |||
1469 | { | |||
1470 | int i; | |||
1471 | ||||
1472 | for (i = 0; i < NUM_CACHES2; i++) { | |||
1473 | while (chillbufs(&cleancache[i], &cleancache[i].warmqueue, | |||
1474 | &cleancache[i].warmbufpages) || | |||
1475 | chillbufs(&cleancache[i], &cleancache[i].hotqueue, | |||
1476 | &cleancache[i].hotbufpages)) | |||
1477 | continue; | |||
1478 | } | |||
1479 | } | |||
1480 | ||||
1481 | /* | |||
1482 | * Get a clean buffer from the cache. if "discard" is set do not promote | |||
1483 | * previously warm buffers as normal, because we are tossing everything | |||
1484 | * away such as in a hibernation | |||
1485 | */ | |||
1486 | struct buf * | |||
1487 | bufcache_getcleanbuf(int cachenum, int discard) | |||
1488 | { | |||
1489 | struct buf *bp = NULL((void *)0); | |||
1490 | struct bufcache *cache = &cleancache[cachenum]; | |||
1491 | struct bufqueue * queue; | |||
1492 | ||||
1493 | splassert(IPL_BIO)do { if (splassert_ctl > 0) { splassert_check(0x6, __func__ ); } } while (0); | |||
1494 | ||||
1495 | /* try cold queue */ | |||
1496 | while ((bp = TAILQ_FIRST(&cache->coldqueue)((&cache->coldqueue)->tqh_first)) || | |||
1497 | (bp = TAILQ_FIRST(&cache->warmqueue)((&cache->warmqueue)->tqh_first)) || | |||
1498 | (bp = TAILQ_FIRST(&cache->hotqueue)((&cache->hotqueue)->tqh_first))) { | |||
1499 | int64_t pages = atop(bp->b_bufsize)((bp->b_bufsize) >> 12); | |||
1500 | struct bufcache *newcache; | |||
1501 | ||||
1502 | if (discard || cachenum >= NUM_CACHES2 - 1) { | |||
1503 | /* Victim selected, give it up */ | |||
1504 | return bp; | |||
1505 | } | |||
1506 | KASSERT(bp->cache == cachenum)((bp->cache == cachenum) ? (void)0 : __assert("diagnostic " , "/usr/src/sys/kern/vfs_bio.c", 1506, "bp->cache == cachenum" )); | |||
1507 | ||||
1508 | /* | |||
1509 | * If this buffer was warm before, move it to | |||
1510 | * the hot queue in the next cache | |||
1511 | */ | |||
1512 | ||||
1513 | if (fliphigh) { | |||
1514 | /* | |||
1515 | * If we are in the DMA cache, try to flip the | |||
1516 | * buffer up high to move it on to the other | |||
1517 | * caches. if we can't move the buffer to high | |||
1518 | * memory without sleeping, we give it up and | |||
1519 | * return it rather than fight for more memory | |||
1520 | * against non buffer cache competitors. | |||
1521 | */ | |||
1522 | SET(bp->b_flags, B_BUSY)((bp->b_flags) |= (0x00000010)); | |||
1523 | if (bp->cache == 0 && buf_flip_high(bp) == -1) { | |||
1524 | CLR(bp->b_flags, B_BUSY)((bp->b_flags) &= ~(0x00000010)); | |||
1525 | return bp; | |||
1526 | } | |||
1527 | CLR(bp->b_flags, B_BUSY)((bp->b_flags) &= ~(0x00000010)); | |||
1528 | } | |||
1529 | ||||
1530 | /* Move the buffer to the hot queue in the next cache */ | |||
1531 | if (ISSET(bp->b_flags, B_COLD)((bp->b_flags) & (0x01000000))) { | |||
1532 | queue = &cache->coldqueue; | |||
1533 | } else if (ISSET(bp->b_flags, B_WARM)((bp->b_flags) & (0x00800000))) { | |||
1534 | queue = &cache->warmqueue; | |||
1535 | cache->warmbufpages -= pages; | |||
1536 | } else { | |||
1537 | queue = &cache->hotqueue; | |||
1538 | cache->hotbufpages -= pages; | |||
1539 | } | |||
1540 | TAILQ_REMOVE(queue, bp, b_freelist)do { if (((bp)->b_freelist.tqe_next) != ((void *)0)) (bp)-> b_freelist.tqe_next->b_freelist.tqe_prev = (bp)->b_freelist .tqe_prev; else (queue)->tqh_last = (bp)->b_freelist.tqe_prev ; *(bp)->b_freelist.tqe_prev = (bp)->b_freelist.tqe_next ; ((bp)->b_freelist.tqe_prev) = ((void *)-1); ((bp)->b_freelist .tqe_next) = ((void *)-1); } while (0); | |||
1541 | cache->cachepages -= pages; | |||
1542 | CLR(bp->b_flags, B_WARM)((bp->b_flags) &= ~(0x00800000)); | |||
1543 | CLR(bp->b_flags, B_COLD)((bp->b_flags) &= ~(0x01000000)); | |||
1544 | bp->cache++; | |||
1545 | newcache= &cleancache[bp->cache]; | |||
1546 | newcache->cachepages += pages; | |||
1547 | newcache->hotbufpages += pages; | |||
1548 | chillbufs(newcache, &newcache->hotqueue, | |||
1549 | &newcache->hotbufpages); | |||
1550 | TAILQ_INSERT_TAIL(&newcache->hotqueue, bp, b_freelist)do { (bp)->b_freelist.tqe_next = ((void *)0); (bp)->b_freelist .tqe_prev = (&newcache->hotqueue)->tqh_last; *(& newcache->hotqueue)->tqh_last = (bp); (&newcache-> hotqueue)->tqh_last = &(bp)->b_freelist.tqe_next; } while (0); | |||
1551 | } | |||
1552 | return bp; | |||
1553 | } | |||
1554 | ||||
1555 | ||||
1556 | void | |||
1557 | discard_buffer(struct buf *bp) { | |||
1558 | bufcache_take(bp); | |||
1559 | if (bp->b_vp) { | |||
1560 | RBT_REMOVE(buf_rb_bufs,buf_rb_bufs_RBT_REMOVE(&bp->b_vp->v_bufs_tree, bp) | |||
1561 | &bp->b_vp->v_bufs_tree, bp)buf_rb_bufs_RBT_REMOVE(&bp->b_vp->v_bufs_tree, bp); | |||
1562 | brelvp(bp); | |||
1563 | } | |||
1564 | buf_put(bp); | |||
1565 | } | |||
1566 | ||||
1567 | int64_t | |||
1568 | bufcache_recover_dmapages(int discard, int64_t howmany) | |||
1569 | { | |||
1570 | struct buf *bp = NULL((void *)0); | |||
1571 | struct bufcache *cache = &cleancache[DMA_CACHE0]; | |||
1572 | struct bufqueue * queue; | |||
1573 | int64_t recovered = 0; | |||
1574 | ||||
1575 | splassert(IPL_BIO)do { if (splassert_ctl > 0) { splassert_check(0x6, __func__ ); } } while (0); | |||
1576 | ||||
1577 | while ((recovered < howmany) && | |||
1578 | ((bp = TAILQ_FIRST(&cache->coldqueue)((&cache->coldqueue)->tqh_first)) || | |||
1579 | (bp = TAILQ_FIRST(&cache->warmqueue)((&cache->warmqueue)->tqh_first)) || | |||
1580 | (bp = TAILQ_FIRST(&cache->hotqueue)((&cache->hotqueue)->tqh_first)))) { | |||
1581 | int64_t pages = atop(bp->b_bufsize)((bp->b_bufsize) >> 12); | |||
1582 | struct bufcache *newcache; | |||
1583 | ||||
1584 | if (discard || DMA_CACHE0 >= NUM_CACHES2 - 1) { | |||
1585 | discard_buffer(bp); | |||
1586 | continue; | |||
1587 | } | |||
1588 | KASSERT(bp->cache == DMA_CACHE)((bp->cache == 0) ? (void)0 : __assert("diagnostic ", "/usr/src/sys/kern/vfs_bio.c" , 1588, "bp->cache == DMA_CACHE")); | |||
1589 | ||||
1590 | /* | |||
1591 | * If this buffer was warm before, move it to | |||
1592 | * the hot queue in the next cache | |||
1593 | */ | |||
1594 | ||||
1595 | /* | |||
1596 | * One way or another, the pages for this | |||
1597 | * buffer are leaving DMA memory | |||
1598 | */ | |||
1599 | recovered += pages; | |||
1600 | ||||
1601 | if (!fliphigh) { | |||
1602 | discard_buffer(bp); | |||
1603 | continue; | |||
1604 | } | |||
1605 | ||||
1606 | /* | |||
1607 | * If we are in the DMA cache, try to flip the | |||
1608 | * buffer up high to move it on to the other | |||
1609 | * caches. if we can't move the buffer to high | |||
1610 | * memory without sleeping, we give it up | |||
1611 | * now rather than fight for more memory | |||
1612 | * against non buffer cache competitors. | |||
1613 | */ | |||
1614 | SET(bp->b_flags, B_BUSY)((bp->b_flags) |= (0x00000010)); | |||
1615 | if (bp->cache == 0 && buf_flip_high(bp) == -1) { | |||
1616 | CLR(bp->b_flags, B_BUSY)((bp->b_flags) &= ~(0x00000010)); | |||
1617 | discard_buffer(bp); | |||
1618 | continue; | |||
1619 | } | |||
1620 | CLR(bp->b_flags, B_BUSY)((bp->b_flags) &= ~(0x00000010)); | |||
1621 | ||||
1622 | /* | |||
1623 | * Move the buffer to the hot queue in the next cache | |||
1624 | */ | |||
1625 | if (ISSET(bp->b_flags, B_COLD)((bp->b_flags) & (0x01000000))) { | |||
1626 | queue = &cache->coldqueue; | |||
1627 | } else if (ISSET(bp->b_flags, B_WARM)((bp->b_flags) & (0x00800000))) { | |||
1628 | queue = &cache->warmqueue; | |||
1629 | cache->warmbufpages -= pages; | |||
1630 | } else { | |||
1631 | queue = &cache->hotqueue; | |||
1632 | cache->hotbufpages -= pages; | |||
1633 | } | |||
1634 | TAILQ_REMOVE(queue, bp, b_freelist)do { if (((bp)->b_freelist.tqe_next) != ((void *)0)) (bp)-> b_freelist.tqe_next->b_freelist.tqe_prev = (bp)->b_freelist .tqe_prev; else (queue)->tqh_last = (bp)->b_freelist.tqe_prev ; *(bp)->b_freelist.tqe_prev = (bp)->b_freelist.tqe_next ; ((bp)->b_freelist.tqe_prev) = ((void *)-1); ((bp)->b_freelist .tqe_next) = ((void *)-1); } while (0); | |||
1635 | cache->cachepages -= pages; | |||
1636 | CLR(bp->b_flags, B_WARM)((bp->b_flags) &= ~(0x00800000)); | |||
1637 | CLR(bp->b_flags, B_COLD)((bp->b_flags) &= ~(0x01000000)); | |||
1638 | bp->cache++; | |||
1639 | newcache= &cleancache[bp->cache]; | |||
1640 | newcache->cachepages += pages; | |||
1641 | newcache->hotbufpages += pages; | |||
1642 | chillbufs(newcache, &newcache->hotqueue, | |||
1643 | &newcache->hotbufpages); | |||
1644 | TAILQ_INSERT_TAIL(&newcache->hotqueue, bp, b_freelist)do { (bp)->b_freelist.tqe_next = ((void *)0); (bp)->b_freelist .tqe_prev = (&newcache->hotqueue)->tqh_last; *(& newcache->hotqueue)->tqh_last = (bp); (&newcache-> hotqueue)->tqh_last = &(bp)->b_freelist.tqe_next; } while (0); | |||
1645 | } | |||
1646 | return recovered; | |||
1647 | } | |||
1648 | ||||
1649 | struct buf * | |||
1650 | bufcache_getcleanbuf_range(int start, int end, int discard) | |||
1651 | { | |||
1652 | int i, j = start, q = end; | |||
1653 | struct buf *bp = NULL((void *)0); | |||
1654 | ||||
1655 | /* | |||
1656 | * XXX in theory we could promote warm buffers into a previous queue | |||
1657 | * so in the pathological case of where we go through all the caches | |||
1658 | * without getting a buffer we have to start at the beginning again. | |||
1659 | */ | |||
1660 | while (j <= q) { | |||
1661 | for (i = q; i >= j; i--) | |||
1662 | if ((bp = bufcache_getcleanbuf(i, discard))) | |||
1663 | return (bp); | |||
1664 | j++; | |||
1665 | } | |||
1666 | return bp; | |||
1667 | } | |||
1668 | ||||
1669 | struct buf * | |||
1670 | bufcache_gethighcleanbuf(void) | |||
1671 | { | |||
1672 | if (!fliphigh) | |||
1673 | return NULL((void *)0); | |||
1674 | return bufcache_getcleanbuf_range(DMA_CACHE0 + 1, NUM_CACHES2 - 1, 0); | |||
1675 | } | |||
1676 | ||||
1677 | ||||
1678 | struct buf * | |||
1679 | bufcache_getdmacleanbuf(void) | |||
1680 | { | |||
1681 | if (fliphigh) | |||
1682 | return bufcache_getcleanbuf_range(DMA_CACHE0, DMA_CACHE0, 0); | |||
1683 | return bufcache_getcleanbuf_range(DMA_CACHE0, NUM_CACHES2 - 1, 0); | |||
1684 | } | |||
1685 | ||||
1686 | ||||
1687 | struct buf * | |||
1688 | bufcache_getdirtybuf(void) | |||
1689 | { | |||
1690 | return TAILQ_FIRST(&dirtyqueue)((&dirtyqueue)->tqh_first); | |||
1691 | } | |||
1692 | ||||
1693 | void | |||
1694 | bufcache_take(struct buf *bp) | |||
1695 | { | |||
1696 | struct bufqueue *queue; | |||
1697 | int64_t pages; | |||
1698 | ||||
1699 | splassert(IPL_BIO)do { if (splassert_ctl > 0) { splassert_check(0x6, __func__ ); } } while (0); | |||
1700 | KASSERT(ISSET(bp->b_flags, B_BC))((((bp->b_flags) & (0x02000000))) ? (void)0 : __assert ("diagnostic ", "/usr/src/sys/kern/vfs_bio.c", 1700, "ISSET(bp->b_flags, B_BC)" )); | |||
1701 | KASSERT(bp->cache >= DMA_CACHE)((bp->cache >= 0) ? (void)0 : __assert("diagnostic ", "/usr/src/sys/kern/vfs_bio.c" , 1701, "bp->cache >= DMA_CACHE")); | |||
1702 | KASSERT((bp->cache < NUM_CACHES))(((bp->cache < 2)) ? (void)0 : __assert("diagnostic ", "/usr/src/sys/kern/vfs_bio.c" , 1702, "(bp->cache < NUM_CACHES)")); | |||
1703 | ||||
1704 | pages = atop(bp->b_bufsize)((bp->b_bufsize) >> 12); | |||
1705 | ||||
1706 | TRACEPOINT(vfs, bufcache_take, bp->b_flags, bp->cache, pages)do { extern struct dt_probe (dt_static_vfs_bufcache_take); struct dt_probe *dtp = &(dt_static_vfs_bufcache_take); struct dt_provider *dtpv = dtp->dtp_prov; if (__builtin_expect(((dt_tracing) != 0), 0) && __builtin_expect(((dtp->dtp_recording ) != 0), 0)) { dtpv->dtpv_enter(dtpv, dtp, bp->b_flags, bp->cache, pages); } } while (0); | |||
1707 | ||||
1708 | struct bufcache *cache = &cleancache[bp->cache]; | |||
1709 | if (!ISSET(bp->b_flags, B_DELWRI)((bp->b_flags) & (0x00000080))) { | |||
1710 | if (ISSET(bp->b_flags, B_COLD)((bp->b_flags) & (0x01000000))) { | |||
1711 | queue = &cache->coldqueue; | |||
1712 | } else if (ISSET(bp->b_flags, B_WARM)((bp->b_flags) & (0x00800000))) { | |||
1713 | queue = &cache->warmqueue; | |||
1714 | cache->warmbufpages -= pages; | |||
1715 | } else { | |||
1716 | queue = &cache->hotqueue; | |||
1717 | cache->hotbufpages -= pages; | |||
1718 | } | |||
1719 | bcstats.numcleanpages -= pages; | |||
1720 | cache->cachepages -= pages; | |||
1721 | } else { | |||
1722 | queue = &dirtyqueue; | |||
1723 | bcstats.numdirtypages -= pages; | |||
1724 | bcstats.delwribufs--; | |||
1725 | } | |||
1726 | TAILQ_REMOVE(queue, bp, b_freelist)do { if (((bp)->b_freelist.tqe_next) != ((void *)0)) (bp)-> b_freelist.tqe_next->b_freelist.tqe_prev = (bp)->b_freelist .tqe_prev; else (queue)->tqh_last = (bp)->b_freelist.tqe_prev ; *(bp)->b_freelist.tqe_prev = (bp)->b_freelist.tqe_next ; ((bp)->b_freelist.tqe_prev) = ((void *)-1); ((bp)->b_freelist .tqe_next) = ((void *)-1); } while (0); | |||
1727 | } | |||
1728 | ||||
1729 | /* move buffers from a hot or warm queue to a cold queue in a cache */ | |||
1730 | int | |||
1731 | chillbufs(struct bufcache *cache, struct bufqueue *queue, int64_t *queuepages) | |||
1732 | { | |||
1733 | struct buf *bp; | |||
1734 | int64_t limit, pages; | |||
1735 | ||||
1736 | /* | |||
1737 | * We limit the hot queue to be small, with a max of 4096 pages. | |||
1738 | * We limit the warm queue to half the cache size. | |||
1739 | * | |||
1740 | * We impose a minimum size of 96 to prevent too much "wobbling". | |||
1741 | */ | |||
1742 | if (queue == &cache->hotqueue) | |||
1743 | limit = min(cache->cachepages / 20, 4096); | |||
1744 | else if (queue == &cache->warmqueue) | |||
1745 | limit = (cache->cachepages / 2); | |||
1746 | else | |||
1747 | panic("chillbufs: invalid queue"); | |||
1748 | ||||
1749 | if (*queuepages > 96 && *queuepages > limit) { | |||
1750 | bp = TAILQ_FIRST(queue)((queue)->tqh_first); | |||
1751 | if (!bp) | |||
1752 | panic("inconsistent bufpage counts"); | |||
1753 | pages = atop(bp->b_bufsize)((bp->b_bufsize) >> 12); | |||
1754 | *queuepages -= pages; | |||
1755 | TAILQ_REMOVE(queue, bp, b_freelist)do { if (((bp)->b_freelist.tqe_next) != ((void *)0)) (bp)-> b_freelist.tqe_next->b_freelist.tqe_prev = (bp)->b_freelist .tqe_prev; else (queue)->tqh_last = (bp)->b_freelist.tqe_prev ; *(bp)->b_freelist.tqe_prev = (bp)->b_freelist.tqe_next ; ((bp)->b_freelist.tqe_prev) = ((void *)-1); ((bp)->b_freelist .tqe_next) = ((void *)-1); } while (0); | |||
1756 | /* we do not clear B_WARM */ | |||
1757 | SET(bp->b_flags, B_COLD)((bp->b_flags) |= (0x01000000)); | |||
1758 | TAILQ_INSERT_TAIL(&cache->coldqueue, bp, b_freelist)do { (bp)->b_freelist.tqe_next = ((void *)0); (bp)->b_freelist .tqe_prev = (&cache->coldqueue)->tqh_last; *(&cache ->coldqueue)->tqh_last = (bp); (&cache->coldqueue )->tqh_last = &(bp)->b_freelist.tqe_next; } while ( 0); | |||
1759 | return 1; | |||
1760 | } | |||
1761 | return 0; | |||
1762 | } | |||
1763 | ||||
1764 | void | |||
1765 | bufcache_release(struct buf *bp) | |||
1766 | { | |||
1767 | struct bufqueue *queue; | |||
1768 | int64_t pages; | |||
1769 | struct bufcache *cache = &cleancache[bp->cache]; | |||
1770 | ||||
1771 | KASSERT(ISSET(bp->b_flags, B_BC))((((bp->b_flags) & (0x02000000))) ? (void)0 : __assert ("diagnostic ", "/usr/src/sys/kern/vfs_bio.c", 1771, "ISSET(bp->b_flags, B_BC)" )); | |||
1772 | pages = atop(bp->b_bufsize)((bp->b_bufsize) >> 12); | |||
1773 | ||||
1774 | TRACEPOINT(vfs, bufcache_rel, bp->b_flags, bp->cache, pages)do { extern struct dt_probe (dt_static_vfs_bufcache_rel); struct dt_probe *dtp = &(dt_static_vfs_bufcache_rel); struct dt_provider *dtpv = dtp->dtp_prov; if (__builtin_expect(((dt_tracing) != 0), 0) && __builtin_expect(((dtp->dtp_recording ) != 0), 0)) { dtpv->dtpv_enter(dtpv, dtp, bp->b_flags, bp->cache, pages); } } while (0); | |||
1775 | ||||
1776 | if (fliphigh) { | |||
1777 | if (ISSET(bp->b_flags, B_DMA)((bp->b_flags) & (0x04000000)) && bp->cache > 0) | |||
1778 | panic("B_DMA buffer release from cache %d", | |||
1779 | bp->cache); | |||
1780 | else if ((!ISSET(bp->b_flags, B_DMA)((bp->b_flags) & (0x04000000))) && bp->cache == 0) | |||
1781 | panic("Non B_DMA buffer release from cache %d", | |||
1782 | bp->cache); | |||
1783 | } | |||
1784 | ||||
1785 | if (!ISSET(bp->b_flags, B_DELWRI)((bp->b_flags) & (0x00000080))) { | |||
1786 | int64_t *queuepages; | |||
1787 | if (ISSET(bp->b_flags, B_WARM | B_COLD)((bp->b_flags) & (0x00800000 | 0x01000000))) { | |||
1788 | SET(bp->b_flags, B_WARM)((bp->b_flags) |= (0x00800000)); | |||
1789 | CLR(bp->b_flags, B_COLD)((bp->b_flags) &= ~(0x01000000)); | |||
1790 | queue = &cache->warmqueue; | |||
1791 | queuepages = &cache->warmbufpages; | |||
1792 | } else { | |||
1793 | queue = &cache->hotqueue; | |||
1794 | queuepages = &cache->hotbufpages; | |||
1795 | } | |||
1796 | *queuepages += pages; | |||
1797 | bcstats.numcleanpages += pages; | |||
1798 | cache->cachepages += pages; | |||
1799 | chillbufs(cache, queue, queuepages); | |||
1800 | } else { | |||
1801 | queue = &dirtyqueue; | |||
1802 | bcstats.numdirtypages += pages; | |||
1803 | bcstats.delwribufs++; | |||
1804 | } | |||
1805 | TAILQ_INSERT_TAIL(queue, bp, b_freelist)do { (bp)->b_freelist.tqe_next = ((void *)0); (bp)->b_freelist .tqe_prev = (queue)->tqh_last; *(queue)->tqh_last = (bp ); (queue)->tqh_last = &(bp)->b_freelist.tqe_next; } while (0); | |||
1806 | } | |||
1807 | ||||
1808 | #ifdef HIBERNATE1 | |||
1809 | /* | |||
1810 | * Nuke the buffer cache from orbit when hibernating. We do not want to save | |||
1811 | * any clean cache pages to swap and read them back. the original disk files | |||
1812 | * are just as good. | |||
1813 | */ | |||
1814 | void | |||
1815 | hibernate_suspend_bufcache(void) | |||
1816 | { | |||
1817 | struct buf *bp; | |||
1818 | int s; | |||
1819 | ||||
1820 | s = splbio()splraise(0x6); | |||
1821 | /* Chuck away all the cache pages.. discard bufs, do not promote */ | |||
1822 | while ((bp = bufcache_getcleanbuf_range(DMA_CACHE0, NUM_CACHES2 - 1, 1))) { | |||
1823 | bufcache_take(bp); | |||
1824 | if (bp->b_vp) { | |||
1825 | RBT_REMOVE(buf_rb_bufs, &bp->b_vp->v_bufs_tree, bp)buf_rb_bufs_RBT_REMOVE(&bp->b_vp->v_bufs_tree, bp); | |||
1826 | brelvp(bp); | |||
1827 | } | |||
1828 | buf_put(bp); | |||
1829 | } | |||
1830 | splx(s)spllower(s); | |||
1831 | } | |||
1832 | ||||
1833 | void | |||
1834 | hibernate_resume_bufcache(void) | |||
1835 | { | |||
1836 | /* XXX Nothing needed here for now */ | |||
1837 | } | |||
1838 | #endif /* HIBERNATE */ |