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 * @(#)buf.h 8.9 (Berkeley) 3/30/95
37 * $FreeBSD$
38 */
39
40 #ifndef _SYS_BUF_H_
41 #define _SYS_BUF_H_
42
43 #include <sys/bufobj.h>
44 #include <sys/queue.h>
45 #include <sys/lock.h>
46 #include <sys/lockmgr.h>
47
48 struct bio;
49 struct buf;
50 struct bufobj;
51 struct mount;
52 struct vnode;
53 struct uio;
54
55 /*
56 * To avoid including <ufs/ffs/softdep.h>
57 */
58 LIST_HEAD(workhead, worklist);
59 /*
60 * These are currently used only by the soft dependency code, hence
61 * are stored once in a global variable. If other subsystems wanted
62 * to use these hooks, a pointer to a set of bio_ops could be added
63 * to each buffer.
64 */
65 extern struct bio_ops {
66 void (*io_start)(struct buf *);
67 void (*io_complete)(struct buf *);
68 void (*io_deallocate)(struct buf *);
69 int (*io_countdeps)(struct buf *, int);
70 } bioops;
71
72 struct vm_object;
73 struct vm_page;
74
75 typedef uint32_t b_xflags_t;
76
77 /*
78 * The buffer header describes an I/O operation in the kernel.
79 *
80 * NOTES:
81 * b_bufsize, b_bcount. b_bufsize is the allocation size of the
82 * buffer, either DEV_BSIZE or PAGE_SIZE aligned. b_bcount is the
83 * originally requested buffer size and can serve as a bounds check
84 * against EOF. For most, but not all uses, b_bcount == b_bufsize.
85 *
86 * b_dirtyoff, b_dirtyend. Buffers support piecemeal, unaligned
87 * ranges of dirty data that need to be written to backing store.
88 * The range is typically clipped at b_bcount ( not b_bufsize ).
89 *
90 * b_resid. Number of bytes remaining in I/O. After an I/O operation
91 * completes, b_resid is usually 0 indicating 100% success.
92 *
93 * All fields are protected by the buffer lock except those marked:
94 * V - Protected by owning bufobj lock
95 * Q - Protected by the buf queue lock
96 * D - Protected by an dependency implementation specific lock
97 */
98 struct buf {
99 struct bufobj *b_bufobj;
100 long b_bcount;
101 void *b_caller1;
102 caddr_t b_data;
103 int b_error;
104 uint16_t b_iocmd; /* BIO_* bio_cmd from bio.h */
105 uint16_t b_ioflags; /* BIO_* bio_flags from bio.h */
106 off_t b_iooffset;
107 long b_resid;
108 void (*b_iodone)(struct buf *);
109 void (*b_ckhashcalc)(struct buf *);
110 uint64_t b_ckhash; /* B_CKHASH requested check-hash */
111 daddr_t b_blkno; /* Underlying physical block number. */
112 off_t b_offset; /* Offset into file. */
113 TAILQ_ENTRY(buf) b_bobufs; /* (V) Buffer's associated vnode. */
114 uint32_t b_vflags; /* (V) BV_* flags */
115 uint8_t b_qindex; /* (Q) buffer queue index */
116 uint8_t b_domain; /* (Q) buf domain this resides in */
117 uint16_t b_subqueue; /* (Q) per-cpu q if any */
118 uint32_t b_flags; /* B_* flags. */
119 b_xflags_t b_xflags; /* extra flags */
120 struct lock b_lock; /* Buffer lock */
121 long b_bufsize; /* Allocated buffer size. */
122 int b_runningbufspace; /* when I/O is running, pipelining */
123 int b_kvasize; /* size of kva for buffer */
124 int b_dirtyoff; /* Offset in buffer of dirty region. */
125 int b_dirtyend; /* Offset of end of dirty region. */
126 caddr_t b_kvabase; /* base kva for buffer */
127 daddr_t b_lblkno; /* Logical block number. */
128 struct vnode *b_vp; /* Device vnode. */
129 struct ucred *b_rcred; /* Read credentials reference. */
130 struct ucred *b_wcred; /* Write credentials reference. */
131 union {
132 TAILQ_ENTRY(buf) b_freelist; /* (Q) */
133 struct {
134 void (*b_pgiodone)(void *, vm_page_t *, int, int);
135 int b_pgbefore;
136 int b_pgafter;
137 };
138 };
139 union cluster_info {
140 TAILQ_HEAD(cluster_list_head, buf) cluster_head;
141 TAILQ_ENTRY(buf) cluster_entry;
142 } b_cluster;
143 struct vm_page *b_pages[btoc(MAXPHYS)];
144 int b_npages;
145 struct workhead b_dep; /* (D) List of filesystem dependencies. */
146 void *b_fsprivate1;
147 void *b_fsprivate2;
148 void *b_fsprivate3;
149
150 #if defined(FULL_BUF_TRACKING)
151 #define BUF_TRACKING_SIZE 32
152 #define BUF_TRACKING_ENTRY(x) ((x) & (BUF_TRACKING_SIZE - 1))
153 const char *b_io_tracking[BUF_TRACKING_SIZE];
154 uint32_t b_io_tcnt;
155 #elif defined(BUF_TRACKING)
156 const char *b_io_tracking;
157 #endif
158 };
159
160 #define b_object b_bufobj->bo_object
161
162 /*
163 * These flags are kept in b_flags.
164 *
165 * Notes:
166 *
167 * B_ASYNC VOP calls on bp's are usually async whether or not
168 * B_ASYNC is set, but some subsystems, such as NFS, like
169 * to know what is best for the caller so they can
170 * optimize the I/O.
171 *
172 * B_PAGING Indicates that bp is being used by the paging system or
173 * some paging system and that the bp is not linked into
174 * the b_vp's clean/dirty linked lists or ref counts.
175 * Buffer vp reassignments are illegal in this case.
176 *
177 * B_CACHE This may only be set if the buffer is entirely valid.
178 * The situation where B_DELWRI is set and B_CACHE is
179 * clear MUST be committed to disk by getblk() so
180 * B_DELWRI can also be cleared. See the comments for
181 * getblk() in kern/vfs_bio.c. If B_CACHE is clear,
182 * the caller is expected to clear BIO_ERROR and B_INVAL,
183 * set BIO_READ, and initiate an I/O.
184 *
185 * The 'entire buffer' is defined to be the range from
186 * 0 through b_bcount.
187 *
188 * B_MALLOC Request that the buffer be allocated from the malloc
189 * pool, DEV_BSIZE aligned instead of PAGE_SIZE aligned.
190 *
191 * B_CLUSTEROK This flag is typically set for B_DELWRI buffers
192 * by filesystems that allow clustering when the buffer
193 * is fully dirty and indicates that it may be clustered
194 * with other adjacent dirty buffers. Note the clustering
195 * may not be used with the stage 1 data write under NFS
196 * but may be used for the commit rpc portion.
197 *
198 * B_VMIO Indicates that the buffer is tied into an VM object.
199 * The buffer's data is always PAGE_SIZE aligned even
200 * if b_bufsize and b_bcount are not. ( b_bufsize is
201 * always at least DEV_BSIZE aligned, though ).
202 *
203 * B_DIRECT Hint that we should attempt to completely free
204 * the pages underlying the buffer. B_DIRECT is
205 * sticky until the buffer is released and typically
206 * only has an effect when B_RELBUF is also set.
207 *
208 */
209
210 #define B_AGE 0x00000001 /* Move to age queue when I/O done. */
211 #define B_NEEDCOMMIT 0x00000002 /* Append-write in progress. */
212 #define B_ASYNC 0x00000004 /* Start I/O, do not wait. */
213 #define B_DIRECT 0x00000008 /* direct I/O flag (pls free vmio) */
214 #define B_DEFERRED 0x00000010 /* Skipped over for cleaning */
215 #define B_CACHE 0x00000020 /* Bread found us in the cache. */
216 #define B_VALIDSUSPWRT 0x00000040 /* Valid write during suspension. */
217 #define B_DELWRI 0x00000080 /* Delay I/O until buffer reused. */
218 #define B_CKHASH 0x00000100 /* checksum hash calculated on read */
219 #define B_DONE 0x00000200 /* I/O completed. */
220 #define B_EINTR 0x00000400 /* I/O was interrupted */
221 #define B_NOREUSE 0x00000800 /* Contents not reused once released. */
222 #define B_REUSE 0x00001000 /* Contents reused, second chance. */
223 #define B_INVAL 0x00002000 /* Does not contain valid info. */
224 #define B_BARRIER 0x00004000 /* Write this and all preceding first. */
225 #define B_NOCACHE 0x00008000 /* Do not cache block after use. */
226 #define B_MALLOC 0x00010000 /* malloced b_data */
227 #define B_CLUSTEROK 0x00020000 /* Pagein op, so swap() can count it. */
228 #define B_00040000 0x00040000 /* Available flag. */
229 #define B_00080000 0x00080000 /* Available flag. */
230 #define B_00100000 0x00100000 /* Available flag. */
231 #define B_00200000 0x00200000 /* Available flag. */
232 #define B_RELBUF 0x00400000 /* Release VMIO buffer. */
233 #define B_FS_FLAG1 0x00800000 /* Available flag for FS use. */
234 #define B_NOCOPY 0x01000000 /* Don't copy-on-write this buf. */
235 #define B_INFREECNT 0x02000000 /* buf is counted in numfreebufs */
236 #define B_PAGING 0x04000000 /* volatile paging I/O -- bypass VMIO */
237 #define B_MANAGED 0x08000000 /* Managed by FS. */
238 #define B_RAM 0x10000000 /* Read ahead mark (flag) */
239 #define B_VMIO 0x20000000 /* VMIO flag */
240 #define B_CLUSTER 0x40000000 /* pagein op, so swap() can count it */
241 #define B_REMFREE 0x80000000 /* Delayed bremfree */
242
243 #define PRINT_BUF_FLAGS "\20\40remfree\37cluster\36vmio\35ram\34managed" \
244 "\33paging\32infreecnt\31nocopy\30b23\27relbuf\26b21\25b20" \
245 "\24b19\23b18\22clusterok\21malloc\20nocache\17b14\16inval" \
246 "\15reuse\14noreuse\13eintr\12done\11b8\10delwri" \
247 "\7validsuspwrt\6cache\5deferred\4direct\3async\2needcommit\1age"
248
249 /*
250 * These flags are kept in b_xflags.
251 *
252 * BX_FSPRIV reserves a set of eight flags that may be used by individual
253 * filesystems for their own purpose. Their specific definitions are
254 * found in the header files for each filesystem that uses them.
255 */
256 #define BX_VNDIRTY 0x00000001 /* On vnode dirty list */
257 #define BX_VNCLEAN 0x00000002 /* On vnode clean list */
258 #define BX_BKGRDWRITE 0x00000010 /* Do writes in background */
259 #define BX_BKGRDMARKER 0x00000020 /* Mark buffer for splay tree */
260 #define BX_ALTDATA 0x00000040 /* Holds extended data */
261 #define BX_FSPRIV 0x00FF0000 /* filesystem-specific flags mask */
262
263 #define PRINT_BUF_XFLAGS "\20\7altdata\6bkgrdmarker\5bkgrdwrite\2clean\1dirty"
264
265 #define NOOFFSET (-1LL) /* No buffer offset calculated yet */
266
267 /*
268 * These flags are kept in b_vflags.
269 */
270 #define BV_SCANNED 0x00000001 /* VOP_FSYNC funcs mark written bufs */
271 #define BV_BKGRDINPROG 0x00000002 /* Background write in progress */
272 #define BV_BKGRDWAIT 0x00000004 /* Background write waiting */
273 #define BV_BKGRDERR 0x00000008 /* Error from background write */
274
275 #define PRINT_BUF_VFLAGS "\20\4bkgrderr\3bkgrdwait\2bkgrdinprog\1scanned"
276
277 #ifdef _KERNEL
278 /*
279 * Buffer locking
280 */
281 extern const char *buf_wmesg; /* Default buffer lock message */
282 #define BUF_WMESG "bufwait"
283 #include <sys/proc.h> /* XXX for curthread */
284 #include <sys/mutex.h>
285
286 /*
287 * Initialize a lock.
288 */
289 #define BUF_LOCKINIT(bp) \
290 lockinit(&(bp)->b_lock, PRIBIO + 4, buf_wmesg, 0, 0)
291 /*
292 *
293 * Get a lock sleeping non-interruptably until it becomes available.
294 */
295 #define BUF_LOCK(bp, locktype, interlock) \
296 _lockmgr_args_rw(&(bp)->b_lock, (locktype), (interlock), \
297 LK_WMESG_DEFAULT, LK_PRIO_DEFAULT, LK_TIMO_DEFAULT, \
298 LOCK_FILE, LOCK_LINE)
299
300 /*
301 * Get a lock sleeping with specified interruptably and timeout.
302 */
303 #define BUF_TIMELOCK(bp, locktype, interlock, wmesg, catch, timo) \
304 _lockmgr_args_rw(&(bp)->b_lock, (locktype) | LK_TIMELOCK, \
305 (interlock), (wmesg), (PRIBIO + 4) | (catch), (timo), \
306 LOCK_FILE, LOCK_LINE)
307
308 /*
309 * Release a lock. Only the acquiring process may free the lock unless
310 * it has been handed off to biodone.
311 */
312 #define BUF_UNLOCK(bp) do { \
313 KASSERT(((bp)->b_flags & B_REMFREE) == 0, \
314 ("BUF_UNLOCK %p while B_REMFREE is still set.", (bp))); \
315 \
316 (void)_lockmgr_args(&(bp)->b_lock, LK_RELEASE, NULL, \
317 LK_WMESG_DEFAULT, LK_PRIO_DEFAULT, LK_TIMO_DEFAULT, \
318 LOCK_FILE, LOCK_LINE); \
319 } while (0)
320
321 /*
322 * Check if a buffer lock is recursed.
323 */
324 #define BUF_LOCKRECURSED(bp) \
325 lockmgr_recursed(&(bp)->b_lock)
326
327 /*
328 * Check if a buffer lock is currently held.
329 */
330 #define BUF_ISLOCKED(bp) \
331 lockstatus(&(bp)->b_lock)
332 /*
333 * Free a buffer lock.
334 */
335 #define BUF_LOCKFREE(bp) \
336 lockdestroy(&(bp)->b_lock)
337
338 /*
339 * Print informations on a buffer lock.
340 */
341 #define BUF_LOCKPRINTINFO(bp) \
342 lockmgr_printinfo(&(bp)->b_lock)
343
344 /*
345 * Buffer lock assertions.
346 */
347 #if defined(INVARIANTS) && defined(INVARIANT_SUPPORT)
348 #define BUF_ASSERT_LOCKED(bp) \
349 _lockmgr_assert(&(bp)->b_lock, KA_LOCKED, LOCK_FILE, LOCK_LINE)
350 #define BUF_ASSERT_SLOCKED(bp) \
351 _lockmgr_assert(&(bp)->b_lock, KA_SLOCKED, LOCK_FILE, LOCK_LINE)
352 #define BUF_ASSERT_XLOCKED(bp) \
353 _lockmgr_assert(&(bp)->b_lock, KA_XLOCKED, LOCK_FILE, LOCK_LINE)
354 #define BUF_ASSERT_UNLOCKED(bp) \
355 _lockmgr_assert(&(bp)->b_lock, KA_UNLOCKED, LOCK_FILE, LOCK_LINE)
356 #define BUF_ASSERT_HELD(bp)
357 #define BUF_ASSERT_UNHELD(bp)
358 #else
359 #define BUF_ASSERT_LOCKED(bp)
360 #define BUF_ASSERT_SLOCKED(bp)
361 #define BUF_ASSERT_XLOCKED(bp)
362 #define BUF_ASSERT_UNLOCKED(bp)
363 #define BUF_ASSERT_HELD(bp)
364 #define BUF_ASSERT_UNHELD(bp)
365 #endif
366
367 #ifdef _SYS_PROC_H_ /* Avoid #include <sys/proc.h> pollution */
368 /*
369 * When initiating asynchronous I/O, change ownership of the lock to the
370 * kernel. Once done, the lock may legally released by biodone. The
371 * original owning process can no longer acquire it recursively, but must
372 * wait until the I/O is completed and the lock has been freed by biodone.
373 */
374 #define BUF_KERNPROC(bp) \
375 _lockmgr_disown(&(bp)->b_lock, LOCK_FILE, LOCK_LINE)
376 #endif
377
378 #endif /* _KERNEL */
379
380 struct buf_queue_head {
381 TAILQ_HEAD(buf_queue, buf) queue;
382 daddr_t last_pblkno;
383 struct buf *insert_point;
384 struct buf *switch_point;
385 };
386
387 /*
388 * This structure describes a clustered I/O.
389 */
390 struct cluster_save {
391 long bs_bcount; /* Saved b_bcount. */
392 long bs_bufsize; /* Saved b_bufsize. */
393 int bs_nchildren; /* Number of associated buffers. */
394 struct buf **bs_children; /* List of associated buffers. */
395 };
396
397 #ifdef _KERNEL
398
399 static __inline int
bwrite(struct buf * bp)400 bwrite(struct buf *bp)
401 {
402
403 KASSERT(bp->b_bufobj != NULL, ("bwrite: no bufobj bp=%p", bp));
404 KASSERT(bp->b_bufobj->bo_ops != NULL, ("bwrite: no bo_ops bp=%p", bp));
405 KASSERT(bp->b_bufobj->bo_ops->bop_write != NULL,
406 ("bwrite: no bop_write bp=%p", bp));
407 return (BO_WRITE(bp->b_bufobj, bp));
408 }
409
410 static __inline void
bstrategy(struct buf * bp)411 bstrategy(struct buf *bp)
412 {
413
414 KASSERT(bp->b_bufobj != NULL, ("bstrategy: no bufobj bp=%p", bp));
415 KASSERT(bp->b_bufobj->bo_ops != NULL,
416 ("bstrategy: no bo_ops bp=%p", bp));
417 KASSERT(bp->b_bufobj->bo_ops->bop_strategy != NULL,
418 ("bstrategy: no bop_strategy bp=%p", bp));
419 BO_STRATEGY(bp->b_bufobj, bp);
420 }
421
422 static __inline void
buf_start(struct buf * bp)423 buf_start(struct buf *bp)
424 {
425 if (bioops.io_start)
426 (*bioops.io_start)(bp);
427 }
428
429 static __inline void
buf_complete(struct buf * bp)430 buf_complete(struct buf *bp)
431 {
432 if (bioops.io_complete)
433 (*bioops.io_complete)(bp);
434 }
435
436 static __inline void
buf_deallocate(struct buf * bp)437 buf_deallocate(struct buf *bp)
438 {
439 if (bioops.io_deallocate)
440 (*bioops.io_deallocate)(bp);
441 }
442
443 static __inline int
buf_countdeps(struct buf * bp,int i)444 buf_countdeps(struct buf *bp, int i)
445 {
446 if (bioops.io_countdeps)
447 return ((*bioops.io_countdeps)(bp, i));
448 else
449 return (0);
450 }
451
452 static __inline void
buf_track(struct buf * bp,const char * location)453 buf_track(struct buf *bp, const char *location)
454 {
455
456 #if defined(FULL_BUF_TRACKING)
457 bp->b_io_tracking[BUF_TRACKING_ENTRY(bp->b_io_tcnt++)] = location;
458 #elif defined(BUF_TRACKING)
459 bp->b_io_tracking = location;
460 #endif
461 }
462
463 #endif /* _KERNEL */
464
465 /*
466 * Zero out the buffer's data area.
467 */
468 #define clrbuf(bp) { \
469 bzero((bp)->b_data, (u_int)(bp)->b_bcount); \
470 (bp)->b_resid = 0; \
471 }
472
473 /*
474 * Flags for getblk's last parameter.
475 */
476 #define GB_LOCK_NOWAIT 0x0001 /* Fail if we block on a buf lock. */
477 #define GB_NOCREAT 0x0002 /* Don't create a buf if not found. */
478 #define GB_NOWAIT_BD 0x0004 /* Do not wait for bufdaemon. */
479 #define GB_UNMAPPED 0x0008 /* Do not mmap buffer pages. */
480 #define GB_KVAALLOC 0x0010 /* But allocate KVA. */
481 #define GB_CKHASH 0x0020 /* If reading, calc checksum hash */
482 #define GB_NOSPARSE 0x0040 /* Do not instantiate holes */
483
484 #ifdef _KERNEL
485 extern int nbuf; /* The number of buffer headers */
486 extern long maxswzone; /* Max KVA for swap structures */
487 extern long maxbcache; /* Max KVA for buffer cache */
488 extern int maxbcachebuf; /* Max buffer cache block size */
489 extern long runningbufspace;
490 extern long hibufspace;
491 extern int dirtybufthresh;
492 extern int bdwriteskip;
493 extern int dirtybufferflushes;
494 extern int altbufferflushes;
495 extern int nswbuf; /* Number of swap I/O buffer headers. */
496 extern int cluster_pbuf_freecnt; /* Number of pbufs for clusters */
497 extern int vnode_pbuf_freecnt; /* Number of pbufs for vnode pager */
498 extern int vnode_async_pbuf_freecnt; /* Number of pbufs for vnode pager,
499 asynchronous reads */
500 extern caddr_t unmapped_buf; /* Data address for unmapped buffers. */
501
502 static inline int
buf_mapped(struct buf * bp)503 buf_mapped(struct buf *bp)
504 {
505
506 return (bp->b_data != unmapped_buf);
507 }
508
509 void runningbufwakeup(struct buf *);
510 void waitrunningbufspace(void);
511 caddr_t kern_vfs_bio_buffer_alloc(caddr_t v, long physmem_est);
512 void bufinit(void);
513 void bufshutdown(int);
514 void bdata2bio(struct buf *bp, struct bio *bip);
515 void bwillwrite(void);
516 int buf_dirty_count_severe(void);
517 void bremfree(struct buf *);
518 void bremfreef(struct buf *); /* XXX Force bremfree, only for nfs. */
519 #define bread(vp, blkno, size, cred, bpp) \
520 breadn_flags(vp, blkno, size, NULL, NULL, 0, cred, 0, NULL, bpp)
521 #define bread_gb(vp, blkno, size, cred, gbflags, bpp) \
522 breadn_flags(vp, blkno, size, NULL, NULL, 0, cred, \
523 gbflags, NULL, bpp)
524 #define breadn(vp, blkno, size, rablkno, rabsize, cnt, cred, bpp) \
525 breadn_flags(vp, blkno, size, rablkno, rabsize, cnt, cred, \
526 0, NULL, bpp)
527 int breadn_flags(struct vnode *, daddr_t, int, daddr_t *, int *, int,
528 struct ucred *, int, void (*)(struct buf *), struct buf **);
529 void bdwrite(struct buf *);
530 void bawrite(struct buf *);
531 void babarrierwrite(struct buf *);
532 int bbarrierwrite(struct buf *);
533 void bdirty(struct buf *);
534 void bundirty(struct buf *);
535 void bufstrategy(struct bufobj *, struct buf *);
536 void brelse(struct buf *);
537 void bqrelse(struct buf *);
538 int vfs_bio_awrite(struct buf *);
539 void vfs_drain_busy_pages(struct buf *bp);
540 struct buf * getpbuf(int *);
541 struct buf *incore(struct bufobj *, daddr_t);
542 struct buf *gbincore(struct bufobj *, daddr_t);
543 struct buf *getblk(struct vnode *, daddr_t, int, int, int, int);
544 int getblkx(struct vnode *vp, daddr_t blkno, int size, int slpflag,
545 int slptimeo, int flags, struct buf **bpp);
546 struct buf *geteblk(int, int);
547 int bufwait(struct buf *);
548 int bufwrite(struct buf *);
549 void bufdone(struct buf *);
550 void bd_speedup(void);
551
552 int cluster_read(struct vnode *, u_quad_t, daddr_t, long,
553 struct ucred *, long, int, int, struct buf **);
554 int cluster_wbuild(struct vnode *, long, daddr_t, int, int);
555 void cluster_write(struct vnode *, struct buf *, u_quad_t, int, int);
556 void vfs_bio_brelse(struct buf *bp, int ioflags);
557 void vfs_bio_bzero_buf(struct buf *bp, int base, int size);
558 void vfs_bio_clrbuf(struct buf *);
559 void vfs_bio_set_flags(struct buf *bp, int ioflags);
560 void vfs_bio_set_valid(struct buf *, int base, int size);
561 void vfs_busy_pages(struct buf *, int clear_modify);
562 void vfs_unbusy_pages(struct buf *);
563 int vmapbuf(struct buf *, int);
564 void vunmapbuf(struct buf *);
565 void relpbuf(struct buf *, int *);
566 void brelvp(struct buf *);
567 void bgetvp(struct vnode *, struct buf *);
568 void pbgetbo(struct bufobj *bo, struct buf *bp);
569 void pbgetvp(struct vnode *, struct buf *);
570 void pbrelbo(struct buf *);
571 void pbrelvp(struct buf *);
572 int allocbuf(struct buf *bp, int size);
573 void reassignbuf(struct buf *);
574 struct buf *trypbuf(int *);
575 void bwait(struct buf *, u_char, const char *);
576 void bdone(struct buf *);
577
578 typedef daddr_t (vbg_get_lblkno_t)(struct vnode *, vm_ooffset_t);
579 typedef int (vbg_get_blksize_t)(struct vnode *, daddr_t);
580 int vfs_bio_getpages(struct vnode *vp, struct vm_page **ma, int count,
581 int *rbehind, int *rahead, vbg_get_lblkno_t get_lblkno,
582 vbg_get_blksize_t get_blksize);
583
584 #endif /* _KERNEL */
585
586 #endif /* !_SYS_BUF_H_ */
587