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 */
38
39 #ifndef _SYS_BUF_H_
40 #define _SYS_BUF_H_
41
42 #include <sys/bufobj.h>
43 #include <sys/queue.h>
44 #include <sys/lock.h>
45 #include <sys/lockmgr.h>
46 #include <vm/uma.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 int b_npages;
144 struct workhead b_dep; /* (D) List of filesystem dependencies. */
145 void *b_fsprivate1;
146 void *b_fsprivate2;
147 void *b_fsprivate3;
148
149 #if defined(FULL_BUF_TRACKING)
150 #define BUF_TRACKING_SIZE 32
151 #define BUF_TRACKING_ENTRY(x) ((x) & (BUF_TRACKING_SIZE - 1))
152 const char *b_io_tracking[BUF_TRACKING_SIZE];
153 uint32_t b_io_tcnt;
154 #elif defined(BUF_TRACKING)
155 const char *b_io_tracking;
156 #endif
157 struct vm_page *b_pages[];
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_INVALONERR This flag is set on dirty buffers. It specifies that a
199 * write error should forcibly invalidate the buffer
200 * contents. This flag should be used with caution, as it
201 * discards data. It is incompatible with B_ASYNC.
202 *
203 * B_VMIO Indicates that the buffer is tied into an VM object.
204 * The buffer's data is always PAGE_SIZE aligned even
205 * if b_bufsize and b_bcount are not. ( b_bufsize is
206 * always at least DEV_BSIZE aligned, though ).
207 *
208 * B_DIRECT Hint that we should attempt to completely free
209 * the pages underlying the buffer. B_DIRECT is
210 * sticky until the buffer is released and typically
211 * only has an effect when B_RELBUF is also set.
212 *
213 */
214
215 #define B_AGE 0x00000001 /* Move to age queue when I/O done. */
216 #define B_NEEDCOMMIT 0x00000002 /* Append-write in progress. */
217 #define B_ASYNC 0x00000004 /* Start I/O, do not wait. */
218 #define B_DIRECT 0x00000008 /* direct I/O flag (pls free vmio) */
219 #define B_DEFERRED 0x00000010 /* Skipped over for cleaning */
220 #define B_CACHE 0x00000020 /* Bread found us in the cache. */
221 #define B_VALIDSUSPWRT 0x00000040 /* Valid write during suspension. */
222 #define B_DELWRI 0x00000080 /* Delay I/O until buffer reused. */
223 #define B_CKHASH 0x00000100 /* checksum hash calculated on read */
224 #define B_DONE 0x00000200 /* I/O completed. */
225 #define B_EINTR 0x00000400 /* I/O was interrupted */
226 #define B_NOREUSE 0x00000800 /* Contents not reused once released. */
227 #define B_REUSE 0x00001000 /* Contents reused, second chance. */
228 #define B_INVAL 0x00002000 /* Does not contain valid info. */
229 #define B_BARRIER 0x00004000 /* Write this and all preceding first. */
230 #define B_NOCACHE 0x00008000 /* Do not cache block after use. */
231 #define B_MALLOC 0x00010000 /* malloced b_data */
232 #define B_CLUSTEROK 0x00020000 /* Pagein op, so swap() can count it. */
233 #define B_INVALONERR 0x00040000 /* Invalidate on write error. */
234 #define B_IOSTARTED 0x00080000 /* buf_start() called */
235 #define B_00100000 0x00100000 /* Available flag. */
236 #define B_MAXPHYS 0x00200000 /* nitems(b_pages[]) = atop(MAXPHYS). */
237 #define B_RELBUF 0x00400000 /* Release VMIO buffer. */
238 #define B_FS_FLAG1 0x00800000 /* Available flag for FS use. */
239 #define B_NOCOPY 0x01000000 /* Don't copy-on-write this buf. */
240 #define B_INFREECNT 0x02000000 /* buf is counted in numfreebufs */
241 #define B_PAGING 0x04000000 /* volatile paging I/O -- bypass VMIO */
242 #define B_MANAGED 0x08000000 /* Managed by FS. */
243 #define B_RAM 0x10000000 /* Read ahead mark (flag) */
244 #define B_VMIO 0x20000000 /* VMIO flag */
245 #define B_CLUSTER 0x40000000 /* pagein op, so swap() can count it */
246 #define B_REMFREE 0x80000000 /* Delayed bremfree */
247
248 #define PRINT_BUF_FLAGS "\20\40remfree\37cluster\36vmio\35ram\34managed" \
249 "\33paging\32infreecnt\31nocopy\30b23\27relbuf\26maxphys\25b20" \
250 "\24iostarted\23invalonerr\22clusterok\21malloc\20nocache\17b14" \
251 "\16inval\15reuse\14noreuse\13eintr\12done\11b8\10delwri" \
252 "\7validsuspwrt\6cache\5deferred\4direct\3async\2needcommit\1age"
253
254 /*
255 * These flags are kept in b_xflags.
256 *
257 * BX_FSPRIV reserves a set of eight flags that may be used by individual
258 * filesystems for their own purpose. Their specific definitions are
259 * found in the header files for each filesystem that uses them.
260 */
261 #define BX_VNDIRTY 0x00000001 /* On vnode dirty list */
262 #define BX_VNCLEAN 0x00000002 /* On vnode clean list */
263 #define BX_CVTENXIO 0x00000004 /* Convert errors to ENXIO */
264 #define BX_BKGRDWRITE 0x00000010 /* Do writes in background */
265 #define BX_BKGRDMARKER 0x00000020 /* Mark buffer for splay tree */
266 #define BX_ALTDATA 0x00000040 /* Holds extended data */
267 #define BX_FSPRIV 0x00FF0000 /* Filesystem-specific flags mask */
268
269 #define PRINT_BUF_XFLAGS "\20\7altdata\6bkgrdmarker\5bkgrdwrite\3cvtenxio" \
270 "\2clean\1dirty"
271
272 #define NOOFFSET (-1LL) /* No buffer offset calculated yet */
273
274 /*
275 * These flags are kept in b_vflags.
276 */
277 #define BV_SCANNED 0x00000001 /* VOP_FSYNC funcs mark written bufs */
278 #define BV_BKGRDINPROG 0x00000002 /* Background write in progress */
279 #define BV_BKGRDWAIT 0x00000004 /* Background write waiting */
280 #define BV_BKGRDERR 0x00000008 /* Error from background write */
281
282 #define PRINT_BUF_VFLAGS "\20\4bkgrderr\3bkgrdwait\2bkgrdinprog\1scanned"
283
284 #ifdef _KERNEL
285
286 #ifndef NSWBUF_MIN
287 #define NSWBUF_MIN 16
288 #endif
289
290 /*
291 * Buffer locking
292 */
293 #include <sys/proc.h> /* XXX for curthread */
294 #include <sys/mutex.h>
295
296 /*
297 * Initialize a lock.
298 */
299 #define BUF_LOCKINIT(bp, wmesg) \
300 lockinit(&(bp)->b_lock, PRIBIO + 4, wmesg, 0, LK_NEW)
301 /*
302 *
303 * Get a lock sleeping non-interruptably until it becomes available.
304 */
305 #define BUF_LOCK(bp, locktype, interlock) \
306 _lockmgr_args_rw(&(bp)->b_lock, (locktype), (interlock), \
307 LK_WMESG_DEFAULT, LK_PRIO_DEFAULT, LK_TIMO_DEFAULT, \
308 LOCK_FILE, LOCK_LINE)
309
310 /*
311 * Get a lock sleeping with specified interruptably and timeout.
312 */
313 #define BUF_TIMELOCK(bp, locktype, interlock, wmesg, catch, timo) \
314 _lockmgr_args_rw(&(bp)->b_lock, (locktype) | LK_TIMELOCK, \
315 (interlock), (wmesg), (PRIBIO + 4) | (catch), (timo), \
316 LOCK_FILE, LOCK_LINE)
317
318 /*
319 * Release a lock. Only the acquiring process may free the lock unless
320 * it has been handed off to biodone.
321 */
322 #define BUF_UNLOCK(bp) do { \
323 KASSERT(((bp)->b_flags & B_REMFREE) == 0, \
324 ("BUF_UNLOCK %p while B_REMFREE is still set.", (bp))); \
325 \
326 BUF_UNLOCK_RAW((bp)); \
327 } while (0)
328 #define BUF_UNLOCK_RAW(bp) do { \
329 (void)_lockmgr_args(&(bp)->b_lock, LK_RELEASE, NULL, \
330 LK_WMESG_DEFAULT, LK_PRIO_DEFAULT, LK_TIMO_DEFAULT, \
331 LOCK_FILE, LOCK_LINE); \
332 } while (0)
333
334 /*
335 * Check if a buffer lock is recursed.
336 */
337 #define BUF_LOCKRECURSED(bp) \
338 lockmgr_recursed(&(bp)->b_lock)
339
340 /*
341 * Check if a buffer lock is currently held.
342 */
343 #define BUF_ISLOCKED(bp) \
344 lockstatus(&(bp)->b_lock)
345 /*
346 * Free a buffer lock.
347 */
348 #define BUF_LOCKFREE(bp) \
349 lockdestroy(&(bp)->b_lock)
350
351 /*
352 * Print informations on a buffer lock.
353 */
354 #define BUF_LOCKPRINTINFO(bp) \
355 lockmgr_printinfo(&(bp)->b_lock)
356
357 /*
358 * Buffer lock assertions.
359 */
360 #if defined(INVARIANTS) && defined(INVARIANT_SUPPORT)
361 #define BUF_ASSERT_LOCKED(bp) \
362 _lockmgr_assert(&(bp)->b_lock, KA_LOCKED, LOCK_FILE, LOCK_LINE)
363 #define BUF_ASSERT_SLOCKED(bp) \
364 _lockmgr_assert(&(bp)->b_lock, KA_SLOCKED, LOCK_FILE, LOCK_LINE)
365 #define BUF_ASSERT_XLOCKED(bp) \
366 _lockmgr_assert(&(bp)->b_lock, KA_XLOCKED, LOCK_FILE, LOCK_LINE)
367 #define BUF_ASSERT_UNLOCKED(bp) \
368 _lockmgr_assert(&(bp)->b_lock, KA_UNLOCKED, LOCK_FILE, LOCK_LINE)
369 #else
370 #define BUF_ASSERT_LOCKED(bp)
371 #define BUF_ASSERT_SLOCKED(bp)
372 #define BUF_ASSERT_XLOCKED(bp)
373 #define BUF_ASSERT_UNLOCKED(bp)
374 #endif
375
376 #ifdef _SYS_PROC_H_ /* Avoid #include <sys/proc.h> pollution */
377 /*
378 * When initiating asynchronous I/O, change ownership of the lock to the
379 * kernel. Once done, the lock may legally released by biodone. The
380 * original owning process can no longer acquire it recursively, but must
381 * wait until the I/O is completed and the lock has been freed by biodone.
382 */
383 #define BUF_KERNPROC(bp) \
384 _lockmgr_disown(&(bp)->b_lock, LOCK_FILE, LOCK_LINE)
385 #endif
386
387 #endif /* _KERNEL */
388
389 struct buf_queue_head {
390 TAILQ_HEAD(buf_queue, buf) queue;
391 daddr_t last_pblkno;
392 struct buf *insert_point;
393 struct buf *switch_point;
394 };
395
396 /*
397 * This structure describes a clustered I/O.
398 */
399 struct cluster_save {
400 long bs_bcount; /* Saved b_bcount. */
401 long bs_bufsize; /* Saved b_bufsize. */
402 int bs_nchildren; /* Number of associated buffers. */
403 struct buf **bs_children; /* List of associated buffers. */
404 };
405
406 #ifdef _KERNEL
407
408 static __inline int
bwrite(struct buf * bp)409 bwrite(struct buf *bp)
410 {
411
412 KASSERT(bp->b_bufobj != NULL, ("bwrite: no bufobj bp=%p", bp));
413 KASSERT(bp->b_bufobj->bo_ops != NULL, ("bwrite: no bo_ops bp=%p", bp));
414 KASSERT(bp->b_bufobj->bo_ops->bop_write != NULL,
415 ("bwrite: no bop_write bp=%p", bp));
416 return (BO_WRITE(bp->b_bufobj, bp));
417 }
418
419 static __inline void
bstrategy(struct buf * bp)420 bstrategy(struct buf *bp)
421 {
422
423 KASSERT(bp->b_bufobj != NULL, ("bstrategy: no bufobj bp=%p", bp));
424 KASSERT(bp->b_bufobj->bo_ops != NULL,
425 ("bstrategy: no bo_ops bp=%p", bp));
426 KASSERT(bp->b_bufobj->bo_ops->bop_strategy != NULL,
427 ("bstrategy: no bop_strategy bp=%p", bp));
428 BO_STRATEGY(bp->b_bufobj, bp);
429 }
430
431 static __inline void
buf_start(struct buf * bp)432 buf_start(struct buf *bp)
433 {
434 KASSERT((bp->b_flags & B_IOSTARTED) == 0,
435 ("recursed buf_start %p", bp));
436 bp->b_flags |= B_IOSTARTED;
437 if (bioops.io_start)
438 (*bioops.io_start)(bp);
439 }
440
441 static __inline void
buf_complete(struct buf * bp)442 buf_complete(struct buf *bp)
443 {
444 if ((bp->b_flags & B_IOSTARTED) != 0) {
445 bp->b_flags &= ~B_IOSTARTED;
446 if (bioops.io_complete)
447 (*bioops.io_complete)(bp);
448 }
449 }
450
451 static __inline void
buf_deallocate(struct buf * bp)452 buf_deallocate(struct buf *bp)
453 {
454 if (bioops.io_deallocate)
455 (*bioops.io_deallocate)(bp);
456 }
457
458 static __inline int
buf_countdeps(struct buf * bp,int i)459 buf_countdeps(struct buf *bp, int i)
460 {
461 if (bioops.io_countdeps)
462 return ((*bioops.io_countdeps)(bp, i));
463 else
464 return (0);
465 }
466
467 static __inline void
buf_track(struct buf * bp __unused,const char * location __unused)468 buf_track(struct buf *bp __unused, const char *location __unused)
469 {
470
471 #if defined(FULL_BUF_TRACKING)
472 bp->b_io_tracking[BUF_TRACKING_ENTRY(bp->b_io_tcnt++)] = location;
473 #elif defined(BUF_TRACKING)
474 bp->b_io_tracking = location;
475 #endif
476 }
477
478 #endif /* _KERNEL */
479
480 /*
481 * Zero out the buffer's data area.
482 */
483 #define clrbuf(bp) { \
484 bzero((bp)->b_data, (u_int)(bp)->b_bcount); \
485 (bp)->b_resid = 0; \
486 }
487
488 /*
489 * Flags for getblk's last parameter.
490 */
491 #define GB_LOCK_NOWAIT 0x0001 /* Fail if we block on a buf lock. */
492 #define GB_NOCREAT 0x0002 /* Don't create a buf if not found. */
493 #define GB_NOWAIT_BD 0x0004 /* Do not wait for bufdaemon. */
494 #define GB_UNMAPPED 0x0008 /* Do not mmap buffer pages. */
495 #define GB_KVAALLOC 0x0010 /* But allocate KVA. */
496 #define GB_CKHASH 0x0020 /* If reading, calc checksum hash */
497 #define GB_NOSPARSE 0x0040 /* Do not instantiate holes */
498 #define GB_CVTENXIO 0x0080 /* Convert errors to ENXIO */
499 #define GB_NOWITNESS 0x0100 /* Do not record for WITNESS */
500
501 #ifdef _KERNEL
502 extern int nbuf; /* The number of buffer headers */
503 extern u_long maxswzone; /* Max KVA for swap structures */
504 extern u_long maxbcache; /* Max KVA for buffer cache */
505 extern int maxbcachebuf; /* Max buffer cache block size */
506 extern long runningbufspace;
507 extern long hibufspace;
508 extern int dirtybufthresh;
509 extern int bdwriteskip;
510 extern int dirtybufferflushes;
511 extern int altbufferflushes;
512 extern int nswbuf; /* Number of swap I/O buffer headers. */
513 extern caddr_t __read_mostly unmapped_buf; /* Data address for unmapped
514 buffers. */
515
516 static inline int
buf_mapped(struct buf * bp)517 buf_mapped(struct buf *bp)
518 {
519
520 return (bp->b_data != unmapped_buf);
521 }
522
523 void runningbufwakeup(struct buf *);
524 void waitrunningbufspace(void);
525 caddr_t kern_vfs_bio_buffer_alloc(caddr_t v, long physmem_est);
526 void bufinit(void);
527 void bufshutdown(int);
528 void bdata2bio(struct buf *bp, struct bio *bip);
529 void bwillwrite(void);
530 int buf_dirty_count_severe(void);
531 void bremfree(struct buf *);
532 void bremfreef(struct buf *); /* XXX Force bremfree, only for nfs. */
533 #define bread(vp, blkno, size, cred, bpp) \
534 breadn_flags(vp, blkno, blkno, size, NULL, NULL, 0, cred, 0, \
535 NULL, bpp)
536 #define bread_gb(vp, blkno, size, cred, gbflags, bpp) \
537 breadn_flags(vp, blkno, blkno, size, NULL, NULL, 0, cred, \
538 gbflags, NULL, bpp)
539 #define breadn(vp, blkno, size, rablkno, rabsize, cnt, cred, bpp) \
540 breadn_flags(vp, blkno, blkno, size, rablkno, rabsize, cnt, cred, \
541 0, NULL, bpp)
542 int breadn_flags(struct vnode *, daddr_t, daddr_t, int, daddr_t *, int *,
543 int, struct ucred *, int, void (*)(struct buf *), struct buf **);
544 void bdwrite(struct buf *);
545 void bawrite(struct buf *);
546 void babarrierwrite(struct buf *);
547 int bbarrierwrite(struct buf *);
548 void bdirty(struct buf *);
549 void bundirty(struct buf *);
550 void bufstrategy(struct bufobj *, struct buf *);
551 void brelse(struct buf *);
552 void bqrelse(struct buf *);
553 int vfs_bio_awrite(struct buf *);
554 void vfs_busy_pages_acquire(struct buf *bp);
555 void vfs_busy_pages_release(struct buf *bp);
556 struct buf *incore(struct bufobj *, daddr_t);
557 bool inmem(struct vnode *, daddr_t);
558 struct buf *gbincore(struct bufobj *, daddr_t);
559 struct buf *gbincore_unlocked(struct bufobj *, daddr_t);
560 struct buf *getblk(struct vnode *, daddr_t, int, int, int, int);
561 int getblkx(struct vnode *vp, daddr_t blkno, daddr_t dblkno, int size,
562 int slpflag, int slptimeo, int flags, struct buf **bpp);
563 struct buf *geteblk(int, int);
564 int bufwait(struct buf *);
565 int bufwrite(struct buf *);
566 void bufdone(struct buf *);
567 void bd_speedup(void);
568
569 extern uma_zone_t pbuf_zone;
570 uma_zone_t pbuf_zsecond_create(const char *name, int max);
571
572 int cluster_read(struct vnode *, u_quad_t, daddr_t, long,
573 struct ucred *, long, int, int, struct buf **);
574 int cluster_wbuild(struct vnode *, long, daddr_t, int, int);
575 void cluster_write(struct vnode *, struct buf *, u_quad_t, int, int);
576 void vfs_bio_brelse(struct buf *bp, int ioflags);
577 void vfs_bio_bzero_buf(struct buf *bp, int base, int size);
578 void vfs_bio_clrbuf(struct buf *);
579 void vfs_bio_set_flags(struct buf *bp, int ioflags);
580 void vfs_bio_set_valid(struct buf *, int base, int size);
581 void vfs_busy_pages(struct buf *, int clear_modify);
582 void vfs_unbusy_pages(struct buf *);
583 int vmapbuf(struct buf *, void *, size_t, int);
584 void vunmapbuf(struct buf *);
585 void brelvp(struct buf *);
586 void bgetvp(struct vnode *, struct buf *);
587 void pbgetbo(struct bufobj *bo, struct buf *bp);
588 void pbgetvp(struct vnode *, struct buf *);
589 void pbrelbo(struct buf *);
590 void pbrelvp(struct buf *);
591 int allocbuf(struct buf *bp, int size);
592 void reassignbuf(struct buf *);
593 void bwait(struct buf *, u_char, const char *);
594 void bdone(struct buf *);
595
596 typedef daddr_t (vbg_get_lblkno_t)(struct vnode *, vm_ooffset_t);
597 typedef int (vbg_get_blksize_t)(struct vnode *, daddr_t, long *);
598 int vfs_bio_getpages(struct vnode *vp, struct vm_page **ma, int count,
599 int *rbehind, int *rahead, vbg_get_lblkno_t get_lblkno,
600 vbg_get_blksize_t get_blksize);
601
602 #endif /* _KERNEL */
603
604 #endif /* !_SYS_BUF_H_ */
605