1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1982, 1986, 1989, 1993
5 * The Regents of the University of California. All rights reserved.
6 * (c) UNIX System Laboratories, Inc.
7 * All or some portions of this file are derived from material licensed
8 * to the University of California by American Telephone and Telegraph
9 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
10 * the permission of UNIX System Laboratories, Inc.
11 *
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
14 * are met:
15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright
18 * notice, this list of conditions and the following disclaimer in the
19 * documentation and/or other materials provided with the distribution.
20 * 3. Neither the name of the University nor the names of its contributors
21 * may be used to endorse or promote products derived from this software
22 * without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * SUCH DAMAGE.
35 */
36
37 #ifndef _SYS_BUF_H_
38 #define _SYS_BUF_H_
39
40 #include <sys/bufobj.h>
41 #include <sys/queue.h>
42 #include <sys/lock.h>
43 #include <sys/lockmgr.h>
44 #include <vm/uma.h>
45
46 struct bio;
47 struct buf;
48 struct bufobj;
49 struct mount;
50 struct vnode;
51 struct uio;
52
53 /*
54 * To avoid including <ufs/ffs/softdep.h>
55 */
56 LIST_HEAD(workhead, worklist);
57 /*
58 * These are currently used only by the soft dependency code, hence
59 * are stored once in a global variable. If other subsystems wanted
60 * to use these hooks, a pointer to a set of bio_ops could be added
61 * to each buffer.
62 */
63 extern struct bio_ops {
64 void (*io_start)(struct buf *);
65 void (*io_complete)(struct buf *);
66 void (*io_deallocate)(struct buf *);
67 int (*io_countdeps)(struct buf *, int);
68 } bioops;
69
70 struct vm_object;
71 struct vm_page;
72
73 typedef uint32_t b_xflags_t;
74
75 /*
76 * The buffer header describes an I/O operation in the kernel.
77 *
78 * NOTES:
79 * b_bufsize, b_bcount. b_bufsize is the allocation size of the
80 * buffer, either DEV_BSIZE or PAGE_SIZE aligned. b_bcount is the
81 * originally requested buffer size and can serve as a bounds check
82 * against EOF. For most, but not all uses, b_bcount == b_bufsize.
83 *
84 * b_dirtyoff, b_dirtyend. Buffers support piecemeal, unaligned
85 * ranges of dirty data that need to be written to backing store.
86 * The range is typically clipped at b_bcount ( not b_bufsize ).
87 *
88 * b_resid. Number of bytes remaining in I/O. After an I/O operation
89 * completes, b_resid is usually 0 indicating 100% success.
90 *
91 * All fields are protected by the buffer lock except those marked:
92 * V - Protected by owning bufobj lock
93 * Q - Protected by the buf queue lock
94 * D - Protected by an dependency implementation specific lock
95 */
96 struct buf {
97 struct bufobj *b_bufobj;
98 long b_bcount;
99 void *b_caller1;
100 caddr_t b_data;
101 int b_error;
102 uint16_t b_iocmd; /* BIO_* bio_cmd from bio.h */
103 uint16_t b_ioflags; /* BIO_* bio_flags from bio.h */
104 off_t b_iooffset;
105 long b_resid;
106 void (*b_iodone)(struct buf *);
107 void (*b_ckhashcalc)(struct buf *);
108 uint64_t b_ckhash; /* B_CKHASH requested check-hash */
109 daddr_t b_blkno; /* Underlying physical block number. */
110 off_t b_offset; /* Offset into file. */
111 TAILQ_ENTRY(buf) b_bobufs; /* (V) Buffer's associated vnode. */
112 uint32_t b_vflags; /* (V) BV_* flags */
113 uint8_t b_qindex; /* (Q) buffer queue index */
114 uint8_t b_domain; /* (Q) buf domain this resides in */
115 uint16_t b_subqueue; /* (Q) per-cpu q if any */
116 uint32_t b_flags; /* B_* flags. */
117 b_xflags_t b_xflags; /* extra flags */
118 struct lock b_lock; /* Buffer lock */
119 long b_bufsize; /* Allocated buffer size. */
120 int b_runningbufspace; /* when I/O is running, pipelining */
121 int b_kvasize; /* size of kva for buffer */
122 int b_dirtyoff; /* Offset in buffer of dirty region. */
123 int b_dirtyend; /* Offset of end of dirty region. */
124 caddr_t b_kvabase; /* base kva for buffer */
125 daddr_t b_lblkno; /* Logical block number. */
126 struct vnode *b_vp; /* Device vnode. */
127 struct ucred *b_rcred; /* Read credentials reference. */
128 struct ucred *b_wcred; /* Write credentials reference. */
129 union {
130 TAILQ_ENTRY(buf) b_freelist; /* (Q) */
131 struct {
132 void (*b_pgiodone)(void *, struct vm_page **,
133 int, int);
134 int b_pgbefore;
135 int b_pgafter;
136 };
137 };
138 union cluster_info {
139 TAILQ_HEAD(cluster_list_head, buf) cluster_head;
140 TAILQ_ENTRY(buf) cluster_entry;
141 } b_cluster;
142 int b_npages;
143 struct workhead b_dep; /* (D) List of filesystem dependencies. */
144 void *b_fsprivate1;
145 void *b_fsprivate2;
146 void *b_fsprivate3;
147
148 #if defined(FULL_BUF_TRACKING)
149 #define BUF_TRACKING_SIZE 32
150 #define BUF_TRACKING_ENTRY(x) ((x) & (BUF_TRACKING_SIZE - 1))
151 const char *b_io_tracking[BUF_TRACKING_SIZE];
152 uint32_t b_io_tcnt;
153 #elif defined(BUF_TRACKING)
154 const char *b_io_tracking;
155 #endif
156 struct vm_page *b_pages[];
157 };
158
159 #define b_object b_bufobj->bo_object
160
161 /*
162 * These flags are kept in b_flags.
163 *
164 * Notes:
165 *
166 * B_ASYNC VOP calls on bp's are usually async whether or not
167 * B_ASYNC is set, but some subsystems, such as NFS, like
168 * to know what is best for the caller so they can
169 * optimize the I/O.
170 *
171 * B_PAGING Indicates that bp is being used by the paging system or
172 * some paging system and that the bp is not linked into
173 * the b_vp's clean/dirty linked lists or ref counts.
174 * Buffer vp reassignments are illegal in this case.
175 *
176 * B_CACHE This may only be set if the buffer is entirely valid.
177 * The situation where B_DELWRI is set and B_CACHE is
178 * clear MUST be committed to disk by getblk() so
179 * B_DELWRI can also be cleared. See the comments for
180 * getblk() in kern/vfs_bio.c. If B_CACHE is clear,
181 * the caller is expected to clear BIO_ERROR and B_INVAL,
182 * set BIO_READ, and initiate an I/O.
183 *
184 * The 'entire buffer' is defined to be the range from
185 * 0 through b_bcount.
186 *
187 * B_MALLOC Request that the buffer be allocated from the malloc
188 * pool, DEV_BSIZE aligned instead of PAGE_SIZE aligned.
189 *
190 * B_CLUSTEROK This flag is typically set for B_DELWRI buffers
191 * by filesystems that allow clustering when the buffer
192 * is fully dirty and indicates that it may be clustered
193 * with other adjacent dirty buffers. Note the clustering
194 * may not be used with the stage 1 data write under NFS
195 * but may be used for the commit rpc portion.
196 *
197 * B_INVALONERR This flag is set on dirty buffers. It specifies that a
198 * write error should forcibly invalidate the buffer
199 * contents. This flag should be used with caution, as it
200 * discards data. It is incompatible with B_ASYNC.
201 *
202 * B_VMIO Indicates that the buffer is tied into an VM object.
203 * The buffer's data is always PAGE_SIZE aligned even
204 * if b_bufsize and b_bcount are not. ( b_bufsize is
205 * always at least DEV_BSIZE aligned, though ).
206 *
207 * B_DIRECT Hint that we should attempt to completely free
208 * the pages underlying the buffer. B_DIRECT is
209 * sticky until the buffer is released and typically
210 * only has an effect when B_RELBUF is also set.
211 *
212 */
213
214 #define B_AGE 0x00000001 /* Move to age queue when I/O done. */
215 #define B_NEEDCOMMIT 0x00000002 /* Append-write in progress. */
216 #define B_ASYNC 0x00000004 /* Start I/O, do not wait. */
217 #define B_DIRECT 0x00000008 /* direct I/O flag (pls free vmio) */
218 #define B_DEFERRED 0x00000010 /* Skipped over for cleaning */
219 #define B_CACHE 0x00000020 /* Bread found us in the cache. */
220 #define B_VALIDSUSPWRT 0x00000040 /* Valid write during suspension. */
221 #define B_DELWRI 0x00000080 /* Delay I/O until buffer reused. */
222 #define B_CKHASH 0x00000100 /* checksum hash calculated on read */
223 #define B_DONE 0x00000200 /* I/O completed. */
224 #define B_EINTR 0x00000400 /* I/O was interrupted */
225 #define B_NOREUSE 0x00000800 /* Contents not reused once released. */
226 #define B_REUSE 0x00001000 /* Contents reused, second chance. */
227 #define B_INVAL 0x00002000 /* Does not contain valid info. */
228 #define B_BARRIER 0x00004000 /* Write this and all preceding first. */
229 #define B_NOCACHE 0x00008000 /* Do not cache block after use. */
230 #define B_MALLOC 0x00010000 /* malloced b_data */
231 #define B_CLUSTEROK 0x00020000 /* Pagein op, so swap() can count it. */
232 #define B_INVALONERR 0x00040000 /* Invalidate on write error. */
233 #define B_IOSTARTED 0x00080000 /* buf_start() called */
234 #define B_00100000 0x00100000 /* Available flag. */
235 #define B_MAXPHYS 0x00200000 /* nitems(b_pages[]) = atop(MAXPHYS). */
236 #define B_RELBUF 0x00400000 /* Release VMIO buffer. */
237 #define B_FS_FLAG1 0x00800000 /* Available flag for FS use. */
238 #define B_NOCOPY 0x01000000 /* Don't copy-on-write this buf. */
239 #define B_INFREECNT 0x02000000 /* buf is counted in numfreebufs */
240 #define B_PAGING 0x04000000 /* volatile paging I/O -- bypass VMIO */
241 #define B_MANAGED 0x08000000 /* Managed by FS. */
242 #define B_RAM 0x10000000 /* Read ahead mark (flag) */
243 #define B_VMIO 0x20000000 /* VMIO flag */
244 #define B_CLUSTER 0x40000000 /* pagein op, so swap() can count it */
245 #define B_REMFREE 0x80000000 /* Delayed bremfree */
246
247 #define PRINT_BUF_FLAGS "\20\40remfree\37cluster\36vmio\35ram\34managed" \
248 "\33paging\32infreecnt\31nocopy\30b23\27relbuf\26maxphys\25b20" \
249 "\24iostarted\23invalonerr\22clusterok\21malloc\20nocache\17b14" \
250 "\16inval\15reuse\14noreuse\13eintr\12done\11b8\10delwri" \
251 "\7validsuspwrt\6cache\5deferred\4direct\3async\2needcommit\1age"
252
253 /*
254 * These flags are kept in b_xflags.
255 *
256 * BX_FSPRIV reserves a set of eight flags that may be used by individual
257 * filesystems for their own purpose. Their specific definitions are
258 * found in the header files for each filesystem that uses them.
259 */
260 #define BX_VNDIRTY 0x00000001 /* On vnode dirty list */
261 #define BX_VNCLEAN 0x00000002 /* On vnode clean list */
262 #define BX_CVTENXIO 0x00000004 /* Convert errors to ENXIO */
263 #define BX_BKGRDWRITE 0x00000010 /* Do writes in background */
264 #define BX_BKGRDMARKER 0x00000020 /* Mark buffer for splay tree */
265 #define BX_ALTDATA 0x00000040 /* Holds extended data */
266 #define BX_FSPRIV 0x00FF0000 /* Filesystem-specific flags mask */
267
268 #define PRINT_BUF_XFLAGS "\20\7altdata\6bkgrdmarker\5bkgrdwrite\3cvtenxio" \
269 "\2clean\1dirty"
270
271 #define NOOFFSET (-1LL) /* No buffer offset calculated yet */
272
273 /*
274 * These flags are kept in b_vflags.
275 */
276 #define BV_SCANNED 0x00000001 /* VOP_FSYNC funcs mark written bufs */
277 #define BV_BKGRDINPROG 0x00000002 /* Background write in progress */
278 #define BV_BKGRDWAIT 0x00000004 /* Background write waiting */
279 #define BV_BKGRDERR 0x00000008 /* Error from background write */
280
281 #define PRINT_BUF_VFLAGS "\20\4bkgrderr\3bkgrdwait\2bkgrdinprog\1scanned"
282
283 #ifdef _KERNEL
284
285 #ifndef NSWBUF_MIN
286 #define NSWBUF_MIN 16
287 #endif
288
289 /*
290 * Buffer locking
291 */
292 #include <sys/proc.h> /* XXX for curthread */
293 #include <sys/mutex.h>
294
295 /*
296 * Initialize a lock.
297 */
298 #define BUF_LOCKINIT(bp, wmesg) \
299 lockinit(&(bp)->b_lock, PRIBIO + 4, wmesg, 0, LK_NEW)
300 /*
301 *
302 * Get a lock sleeping non-interruptably until it becomes available.
303 */
304 #define BUF_LOCK(bp, locktype, interlock) \
305 _lockmgr_args_rw(&(bp)->b_lock, (locktype), (interlock), \
306 LK_WMESG_DEFAULT, LK_PRIO_DEFAULT, LK_TIMO_DEFAULT, \
307 LOCK_FILE, LOCK_LINE)
308
309 /*
310 * Get a lock sleeping with specified interruptably and timeout.
311 */
312 #define BUF_TIMELOCK(bp, locktype, interlock, wmesg, catch, timo) \
313 _lockmgr_args_rw(&(bp)->b_lock, (locktype) | LK_TIMELOCK, \
314 (interlock), (wmesg), (PRIBIO + 4) | (catch), (timo), \
315 LOCK_FILE, LOCK_LINE)
316
317 /*
318 * Release a lock. Only the acquiring process may free the lock unless
319 * it has been handed off to biodone.
320 */
321 #define BUF_UNLOCK(bp) do { \
322 KASSERT(((bp)->b_flags & B_REMFREE) == 0, \
323 ("BUF_UNLOCK %p while B_REMFREE is still set.", (bp))); \
324 \
325 BUF_UNLOCK_RAW((bp)); \
326 } while (0)
327 #define BUF_UNLOCK_RAW(bp) do { \
328 (void)_lockmgr_args(&(bp)->b_lock, LK_RELEASE, NULL, \
329 LK_WMESG_DEFAULT, LK_PRIO_DEFAULT, LK_TIMO_DEFAULT, \
330 LOCK_FILE, LOCK_LINE); \
331 } while (0)
332
333 /*
334 * Check if a buffer lock is recursed.
335 */
336 #define BUF_LOCKRECURSED(bp) \
337 lockmgr_recursed(&(bp)->b_lock)
338
339 /*
340 * Check if a buffer lock is currently held.
341 */
342 #define BUF_ISLOCKED(bp) \
343 lockstatus(&(bp)->b_lock)
344
345 /*
346 * Check if a buffer lock is currently held by LK_KERNPROC.
347 */
348 #define BUF_DISOWNED(bp) \
349 lockmgr_disowned(&(bp)->b_lock)
350
351 /*
352 * Free a buffer lock.
353 */
354 #define BUF_LOCKFREE(bp) \
355 lockdestroy(&(bp)->b_lock)
356
357 /*
358 * Print informations on a buffer lock.
359 */
360 #define BUF_LOCKPRINTINFO(bp) \
361 lockmgr_printinfo(&(bp)->b_lock)
362
363 /*
364 * Buffer lock assertions.
365 */
366 #if defined(INVARIANTS) && defined(INVARIANT_SUPPORT)
367 #define BUF_ASSERT_LOCKED(bp) \
368 _lockmgr_assert(&(bp)->b_lock, KA_LOCKED, LOCK_FILE, LOCK_LINE)
369 #define BUF_ASSERT_SLOCKED(bp) \
370 _lockmgr_assert(&(bp)->b_lock, KA_SLOCKED, LOCK_FILE, LOCK_LINE)
371 #define BUF_ASSERT_XLOCKED(bp) \
372 _lockmgr_assert(&(bp)->b_lock, KA_XLOCKED, LOCK_FILE, LOCK_LINE)
373 #define BUF_ASSERT_UNLOCKED(bp) \
374 _lockmgr_assert(&(bp)->b_lock, KA_UNLOCKED, LOCK_FILE, LOCK_LINE)
375 #else
376 #define BUF_ASSERT_LOCKED(bp)
377 #define BUF_ASSERT_SLOCKED(bp)
378 #define BUF_ASSERT_XLOCKED(bp)
379 #define BUF_ASSERT_UNLOCKED(bp)
380 #endif
381
382 #ifdef _SYS_PROC_H_ /* Avoid #include <sys/proc.h> pollution */
383 /*
384 * When initiating asynchronous I/O, change ownership of the lock to the
385 * kernel. Once done, the lock may legally released by biodone. The
386 * original owning process can no longer acquire it recursively, but must
387 * wait until the I/O is completed and the lock has been freed by biodone.
388 */
389 #define BUF_KERNPROC(bp) \
390 _lockmgr_disown(&(bp)->b_lock, LOCK_FILE, LOCK_LINE)
391 #endif
392
393 #endif /* _KERNEL */
394
395 struct buf_queue_head {
396 TAILQ_HEAD(buf_queue, buf) queue;
397 daddr_t last_pblkno;
398 struct buf *insert_point;
399 struct buf *switch_point;
400 };
401
402 /*
403 * This structure describes a clustered I/O.
404 */
405 struct cluster_save {
406 long bs_bcount; /* Saved b_bcount. */
407 long bs_bufsize; /* Saved b_bufsize. */
408 int bs_nchildren; /* Number of associated buffers. */
409 struct buf **bs_children; /* List of associated buffers. */
410 };
411
412 /*
413 * Vnode clustering tracker
414 */
415 struct vn_clusterw {
416 daddr_t v_cstart; /* v start block of cluster */
417 daddr_t v_lasta; /* v last allocation */
418 daddr_t v_lastw; /* v last write */
419 int v_clen; /* v length of cur. cluster */
420 };
421
422 #ifdef _KERNEL
423
424 static __inline int
bwrite(struct buf * bp)425 bwrite(struct buf *bp)
426 {
427
428 KASSERT(bp->b_bufobj != NULL, ("bwrite: no bufobj bp=%p", bp));
429 KASSERT(bp->b_bufobj->bo_ops != NULL, ("bwrite: no bo_ops bp=%p", bp));
430 KASSERT(bp->b_bufobj->bo_ops->bop_write != NULL,
431 ("bwrite: no bop_write bp=%p", bp));
432 return (BO_WRITE(bp->b_bufobj, bp));
433 }
434
435 static __inline void
bstrategy(struct buf * bp)436 bstrategy(struct buf *bp)
437 {
438
439 KASSERT(bp->b_bufobj != NULL, ("bstrategy: no bufobj bp=%p", bp));
440 KASSERT(bp->b_bufobj->bo_ops != NULL,
441 ("bstrategy: no bo_ops bp=%p", bp));
442 KASSERT(bp->b_bufobj->bo_ops->bop_strategy != NULL,
443 ("bstrategy: no bop_strategy bp=%p", bp));
444 BO_STRATEGY(bp->b_bufobj, bp);
445 }
446
447 static __inline void
buf_start(struct buf * bp)448 buf_start(struct buf *bp)
449 {
450 KASSERT((bp->b_flags & B_IOSTARTED) == 0,
451 ("recursed buf_start %p", bp));
452 bp->b_flags |= B_IOSTARTED;
453 if (bioops.io_start)
454 (*bioops.io_start)(bp);
455 }
456
457 static __inline void
buf_complete(struct buf * bp)458 buf_complete(struct buf *bp)
459 {
460 if ((bp->b_flags & B_IOSTARTED) != 0) {
461 bp->b_flags &= ~B_IOSTARTED;
462 if (bioops.io_complete)
463 (*bioops.io_complete)(bp);
464 }
465 }
466
467 static __inline void
buf_deallocate(struct buf * bp)468 buf_deallocate(struct buf *bp)
469 {
470 if (bioops.io_deallocate)
471 (*bioops.io_deallocate)(bp);
472 }
473
474 static __inline int
buf_countdeps(struct buf * bp,int i)475 buf_countdeps(struct buf *bp, int i)
476 {
477 if (bioops.io_countdeps)
478 return ((*bioops.io_countdeps)(bp, i));
479 else
480 return (0);
481 }
482
483 static __inline void
buf_track(struct buf * bp __unused,const char * location __unused)484 buf_track(struct buf *bp __unused, const char *location __unused)
485 {
486
487 #if defined(FULL_BUF_TRACKING)
488 bp->b_io_tracking[BUF_TRACKING_ENTRY(bp->b_io_tcnt++)] = location;
489 #elif defined(BUF_TRACKING)
490 bp->b_io_tracking = location;
491 #endif
492 }
493
494 #endif /* _KERNEL */
495
496 /*
497 * Zero out the buffer's data area.
498 */
499 #define clrbuf(bp) { \
500 bzero((bp)->b_data, (u_int)(bp)->b_bcount); \
501 (bp)->b_resid = 0; \
502 }
503
504 /*
505 * Flags for getblk's last parameter.
506 */
507 #define GB_LOCK_NOWAIT 0x0001 /* Fail if we block on a buf lock. */
508 #define GB_NOCREAT 0x0002 /* Don't create a buf if not found. */
509 #define GB_NOWAIT_BD 0x0004 /* Do not wait for bufdaemon. */
510 #define GB_UNMAPPED 0x0008 /* Do not mmap buffer pages. */
511 #define GB_KVAALLOC 0x0010 /* But allocate KVA. */
512 #define GB_CKHASH 0x0020 /* If reading, calc checksum hash */
513 #define GB_NOSPARSE 0x0040 /* Do not instantiate holes */
514 #define GB_CVTENXIO 0x0080 /* Convert errors to ENXIO */
515 #define GB_NOWITNESS 0x0100 /* Do not record for WITNESS */
516
517 #ifdef _KERNEL
518 extern int nbuf; /* The number of buffer headers */
519 extern u_long maxswzone; /* Max KVA for swap structures */
520 extern u_long maxbcache; /* Max KVA for buffer cache */
521 extern int maxbcachebuf; /* Max buffer cache block size */
522 extern long runningbufspace;
523 extern long hibufspace;
524 extern int dirtybufthresh;
525 extern int bdwriteskip;
526 extern int dirtybufferflushes;
527 extern int altbufferflushes;
528 extern int nswbuf; /* Number of swap I/O buffer headers. */
529 extern caddr_t __read_mostly unmapped_buf; /* Data address for unmapped
530 buffers. */
531
532 static inline int
buf_mapped(struct buf * bp)533 buf_mapped(struct buf *bp)
534 {
535
536 return (bp->b_data != unmapped_buf);
537 }
538
539 void runningbufwakeup(struct buf *);
540 void waitrunningbufspace(void);
541 caddr_t kern_vfs_bio_buffer_alloc(caddr_t v, long physmem_est);
542 void bufinit(void);
543 void bufshutdown(int);
544 void bdata2bio(struct buf *bp, struct bio *bip);
545 void bwillwrite(void);
546 int buf_dirty_count_severe(void);
547 void bremfree(struct buf *);
548 void bremfreef(struct buf *); /* XXX Force bremfree, only for nfs. */
549 #define bread(vp, blkno, size, cred, bpp) \
550 breadn_flags(vp, blkno, blkno, size, NULL, NULL, 0, cred, 0, \
551 NULL, bpp)
552 #define bread_gb(vp, blkno, size, cred, gbflags, bpp) \
553 breadn_flags(vp, blkno, blkno, size, NULL, NULL, 0, cred, \
554 gbflags, NULL, bpp)
555 #define breadn(vp, blkno, size, rablkno, rabsize, cnt, cred, bpp) \
556 breadn_flags(vp, blkno, blkno, size, rablkno, rabsize, cnt, cred, \
557 0, NULL, bpp)
558 int breadn_flags(struct vnode *, daddr_t, daddr_t, int, daddr_t *, int *,
559 int, struct ucred *, int, void (*)(struct buf *), struct buf **);
560 void bdwrite(struct buf *);
561 void bawrite(struct buf *);
562 void babarrierwrite(struct buf *);
563 int bbarrierwrite(struct buf *);
564 void bdirty(struct buf *);
565 void bundirty(struct buf *);
566 void bufstrategy(struct bufobj *, struct buf *);
567 void brelse(struct buf *);
568 void bqrelse(struct buf *);
569 int vfs_bio_awrite(struct buf *);
570 void vfs_busy_pages_acquire(struct buf *bp);
571 void vfs_busy_pages_release(struct buf *bp);
572 struct buf *incore(struct bufobj *, daddr_t);
573 bool inmem(struct vnode *, daddr_t);
574 struct buf *gbincore(struct bufobj *, daddr_t);
575 struct buf *gbincore_unlocked(struct bufobj *, daddr_t);
576 struct buf *getblk(struct vnode *, daddr_t, int, int, int, int);
577 int getblkx(struct vnode *vp, daddr_t blkno, daddr_t dblkno, int size,
578 int slpflag, int slptimeo, int flags, struct buf **bpp);
579 struct buf *geteblk(int, int);
580 int bufwait(struct buf *);
581 int bufwrite(struct buf *);
582 void bufdone(struct buf *);
583 void bd_speedup(void);
584
585 extern uma_zone_t pbuf_zone;
586 uma_zone_t pbuf_zsecond_create(const char *name, int max);
587
588 struct vn_clusterw;
589
590 void cluster_init_vn(struct vn_clusterw *vnc);
591 int cluster_read(struct vnode *, u_quad_t, daddr_t, long,
592 struct ucred *, long, int, int, struct buf **);
593 int cluster_wbuild(struct vnode *, long, daddr_t, int, int);
594 void cluster_write(struct vnode *, struct vn_clusterw *, struct buf *,
595 u_quad_t, int, int);
596 void vfs_bio_brelse(struct buf *bp, int ioflags);
597 void vfs_bio_bzero_buf(struct buf *bp, int base, int size);
598 void vfs_bio_clrbuf(struct buf *);
599 void vfs_bio_set_flags(struct buf *bp, int ioflags);
600 void vfs_bio_set_valid(struct buf *, int base, int size);
601 void vfs_busy_pages(struct buf *, int clear_modify);
602 void vfs_unbusy_pages(struct buf *);
603 int vmapbuf(struct buf *, void *, size_t, int);
604 void vunmapbuf(struct buf *);
605 void brelvp(struct buf *);
606 int bgetvp(struct vnode *, struct buf *) __result_use_check;
607 void pbgetbo(struct bufobj *bo, struct buf *bp);
608 void pbgetvp(struct vnode *, struct buf *);
609 void pbrelbo(struct buf *);
610 void pbrelvp(struct buf *);
611 int allocbuf(struct buf *bp, int size);
612 void reassignbuf(struct buf *);
613 void bwait(struct buf *, u_char, const char *);
614 void bdone(struct buf *);
615
616 typedef daddr_t (vbg_get_lblkno_t)(struct vnode *, vm_ooffset_t);
617 typedef int (vbg_get_blksize_t)(struct vnode *, daddr_t, long *);
618 int vfs_bio_getpages(struct vnode *vp, struct vm_page **ma, int count,
619 int *rbehind, int *rahead, vbg_get_lblkno_t get_lblkno,
620 vbg_get_blksize_t get_blksize);
621
622 #endif /* _KERNEL */
623
624 #endif /* !_SYS_BUF_H_ */
625