1/*- 2 * Copyright (c) 1982, 1986, 1989, 1993 3 * The Regents of the University of California. All rights reserved. 4 * (c) UNIX System Laboratories, Inc. 5 * All or some portions of this file are derived from material licensed 6 * to the University of California by American Telephone and Telegraph 7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 8 * the permission of UNIX System Laboratories, Inc. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 4. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * @(#)buf.h 8.9 (Berkeley) 3/30/95 35 * $FreeBSD$ 36 */ 37 38#ifndef _SYS_BUF_H_ 39#define _SYS_BUF_H_ 40 41#include <sys/bufobj.h> 42#include <sys/queue.h> 43#include <sys/lock.h> 44#include <sys/lockmgr.h> 45 46struct bio; 47struct buf; 48struct bufobj; 49struct mount; 50struct vnode; 51struct uio; 52 53/* 54 * To avoid including <ufs/ffs/softdep.h> 55 */ 56LIST_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 */ 63extern 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 70struct vm_object; 71 72typedef unsigned char b_xflags_t; 73 74/* 75 * The buffer header describes an I/O operation in the kernel. 76 * 77 * NOTES: 78 * b_bufsize, b_bcount. b_bufsize is the allocation size of the 79 * buffer, either DEV_BSIZE or PAGE_SIZE aligned. b_bcount is the 80 * originally requested buffer size and can serve as a bounds check 81 * against EOF. For most, but not all uses, b_bcount == b_bufsize. 82 * 83 * b_dirtyoff, b_dirtyend. Buffers support piecemeal, unaligned 84 * ranges of dirty data that need to be written to backing store. 85 * The range is typically clipped at b_bcount ( not b_bufsize ). 86 * 87 * b_resid. Number of bytes remaining in I/O. After an I/O operation 88 * completes, b_resid is usually 0 indicating 100% success. 89 * 90 * All fields are protected by the buffer lock except those marked: 91 * V - Protected by owning bufobj lock 92 * Q - Protected by the buf queue lock 93 * D - Protected by an dependency implementation specific lock 94 */ 95struct buf { 96 struct bufobj *b_bufobj; 97 long b_bcount; 98 void *b_caller1; 99 caddr_t b_data; 100 int b_error; 101 uint8_t b_iocmd; 102 uint8_t b_ioflags; 103 off_t b_iooffset; 104 long b_resid; 105 void (*b_iodone)(struct buf *); 106 daddr_t b_blkno; /* Underlying physical block number. */ 107 off_t b_offset; /* Offset into file. */ 108 TAILQ_ENTRY(buf) b_bobufs; /* (V) Buffer's associated vnode. */ 109 struct buf *b_left; /* (V) splay tree link */ 110 struct buf *b_right; /* (V) splay tree link */ 111 uint32_t b_vflags; /* (V) BV_* flags */ 112 TAILQ_ENTRY(buf) b_freelist; /* (Q) Free list position inactive. */ 113 unsigned short b_qindex; /* (Q) buffer queue index */ 114 uint32_t b_flags; /* B_* flags. */ 115 b_xflags_t b_xflags; /* extra flags */ 116 struct lock b_lock; /* Buffer lock */ 117 long b_bufsize; /* Allocated buffer size. */ 118 long b_runningbufspace; /* when I/O is running, pipelining */ 119 caddr_t b_kvabase; /* base kva for buffer */ 120 caddr_t b_kvaalloc; /* allocated kva for B_KVAALLOC */ 121 int b_kvasize; /* size of kva for buffer */ 122 daddr_t b_lblkno; /* Logical block number. */ 123 struct vnode *b_vp; /* Device vnode. */ 124 int b_dirtyoff; /* Offset in buffer of dirty region. */ 125 int b_dirtyend; /* Offset of end of dirty region. */ 126 struct ucred *b_rcred; /* Read credentials reference. */ 127 struct ucred *b_wcred; /* Write credentials reference. */ 128 void *b_saveaddr; /* Original b_addr for physio. */ 129 union pager_info { 130 int pg_reqpage; 131 } b_pager; 132 union cluster_info { 133 TAILQ_HEAD(cluster_list_head, buf) cluster_head; 134 TAILQ_ENTRY(buf) cluster_entry; 135 } b_cluster; 136 struct vm_page *b_pages[btoc(MAXPHYS)]; 137 int b_npages; 138 struct workhead b_dep; /* (D) List of filesystem dependencies. */ 139 void *b_fsprivate1; 140 void *b_fsprivate2; 141 void *b_fsprivate3; 142 int b_pin_count; 143}; 144 145#define b_object b_bufobj->bo_object 146 147/* 148 * These flags are kept in b_flags. 149 * 150 * Notes: 151 * 152 * B_ASYNC VOP calls on bp's are usually async whether or not 153 * B_ASYNC is set, but some subsystems, such as NFS, like 154 * to know what is best for the caller so they can 155 * optimize the I/O. 156 * 157 * B_PAGING Indicates that bp is being used by the paging system or 158 * some paging system and that the bp is not linked into 159 * the b_vp's clean/dirty linked lists or ref counts. 160 * Buffer vp reassignments are illegal in this case. 161 * 162 * B_CACHE This may only be set if the buffer is entirely valid. 163 * The situation where B_DELWRI is set and B_CACHE is 164 * clear MUST be committed to disk by getblk() so 165 * B_DELWRI can also be cleared. See the comments for 166 * getblk() in kern/vfs_bio.c. If B_CACHE is clear, 167 * the caller is expected to clear BIO_ERROR and B_INVAL, 168 * set BIO_READ, and initiate an I/O. 169 * 170 * The 'entire buffer' is defined to be the range from 171 * 0 through b_bcount. 172 * 173 * B_MALLOC Request that the buffer be allocated from the malloc 174 * pool, DEV_BSIZE aligned instead of PAGE_SIZE aligned. 175 * 176 * B_CLUSTEROK This flag is typically set for B_DELWRI buffers 177 * by filesystems that allow clustering when the buffer 178 * is fully dirty and indicates that it may be clustered 179 * with other adjacent dirty buffers. Note the clustering 180 * may not be used with the stage 1 data write under NFS 181 * but may be used for the commit rpc portion. 182 * 183 * B_VMIO Indicates that the buffer is tied into an VM object. 184 * The buffer's data is always PAGE_SIZE aligned even 185 * if b_bufsize and b_bcount are not. ( b_bufsize is 186 * always at least DEV_BSIZE aligned, though ). 187 * 188 * B_DIRECT Hint that we should attempt to completely free 189 * the pages underlying the buffer. B_DIRECT is 190 * sticky until the buffer is released and typically 191 * only has an effect when B_RELBUF is also set. 192 * 193 */ 194 195#define B_AGE 0x00000001 /* Move to age queue when I/O done. */ 196#define B_NEEDCOMMIT 0x00000002 /* Append-write in progress. */ 197#define B_ASYNC 0x00000004 /* Start I/O, do not wait. */ 198#define B_DIRECT 0x00000008 /* direct I/O flag (pls free vmio) */ 199#define B_DEFERRED 0x00000010 /* Skipped over for cleaning */ 200#define B_CACHE 0x00000020 /* Bread found us in the cache. */ 201#define B_VALIDSUSPWRT 0x00000040 /* Valid write during suspension. */ 202#define B_DELWRI 0x00000080 /* Delay I/O until buffer reused. */ 203#define B_PERSISTENT 0x00000100 /* Perm. ref'ed while EXT2FS mounted. */ 204#define B_DONE 0x00000200 /* I/O completed. */ 205#define B_EINTR 0x00000400 /* I/O was interrupted */ 206#define B_UNMAPPED 0x00000800 /* KVA is not mapped. */ 207#define B_KVAALLOC 0x00001000 /* But allocated. */ 208#define B_INVAL 0x00002000 /* Does not contain valid info. */ 209#define B_BARRIER 0x00004000 /* Write this and all preceeding first. */ 210#define B_NOCACHE 0x00008000 /* Do not cache block after use. */ 211#define B_MALLOC 0x00010000 /* malloced b_data */ 212#define B_CLUSTEROK 0x00020000 /* Pagein op, so swap() can count it. */ 213#define B_000400000 0x00040000 /* Available flag. */ 214#define B_000800000 0x00080000 /* Available flag. */ 215#define B_00100000 0x00100000 /* Available flag. */ 216#define B_DIRTY 0x00200000 /* Needs writing later (in EXT2FS). */ 217#define B_RELBUF 0x00400000 /* Release VMIO buffer. */ 218#define B_00800000 0x00800000 /* Available flag. */ 219#define B_NOCOPY 0x01000000 /* Don't copy-on-write this buf. */ 220#define B_NEEDSGIANT 0x02000000 /* Buffer's vnode needs giant. */ 221#define B_PAGING 0x04000000 /* volatile paging I/O -- bypass VMIO */ 222#define B_MANAGED 0x08000000 /* Managed by FS. */ 223#define B_RAM 0x10000000 /* Read ahead mark (flag) */ 224#define B_VMIO 0x20000000 /* VMIO flag */ 225#define B_CLUSTER 0x40000000 /* pagein op, so swap() can count it */ 226#define B_REMFREE 0x80000000 /* Delayed bremfree */ 227 228#define PRINT_BUF_FLAGS "\20\40remfree\37cluster\36vmio\35ram\34managed" \ 229 "\33paging\32needsgiant\31nocopy\30b23\27relbuf\26dirty\25b20" \ 230 "\24b19\23b18\22clusterok\21malloc\20nocache\17b14\16inval" \ 231 "\15b12\14b11\13eintr\12done\11persist\10delwri\7validsuspwrt" \ 232 "\6cache\5deferred\4direct\3async\2needcommit\1age" 233 234/* 235 * These flags are kept in b_xflags. 236 */ 237#define BX_VNDIRTY 0x00000001 /* On vnode dirty list */ 238#define BX_VNCLEAN 0x00000002 /* On vnode clean list */ 239#define BX_BKGRDWRITE 0x00000010 /* Do writes in background */ 240#define BX_BKGRDMARKER 0x00000020 /* Mark buffer for splay tree */ 241#define BX_ALTDATA 0x00000040 /* Holds extended data */ 242 243#define PRINT_BUF_XFLAGS "\20\7altdata\6bkgrdmarker\5bkgrdwrite\2clean\1dirty" 244 245#define NOOFFSET (-1LL) /* No buffer offset calculated yet */ 246 247/* 248 * These flags are kept in b_vflags. 249 */ 250#define BV_SCANNED 0x00000001 /* VOP_FSYNC funcs mark written bufs */ 251#define BV_BKGRDINPROG 0x00000002 /* Background write in progress */ 252#define BV_BKGRDWAIT 0x00000004 /* Background write waiting */ 253#define BV_INFREECNT 0x80000000 /* buf is counted in numfreebufs */ 254 255#define PRINT_BUF_VFLAGS "\20\40infreecnt\3bkgrdwait\2bkgrdinprog\1scanned" 256 257#ifdef _KERNEL 258/* 259 * Buffer locking 260 */ 261extern const char *buf_wmesg; /* Default buffer lock message */ 262#define BUF_WMESG "bufwait" 263#include <sys/proc.h> /* XXX for curthread */ 264#include <sys/mutex.h> 265 266/* 267 * Initialize a lock. 268 */ 269#define BUF_LOCKINIT(bp) \ 270 lockinit(&(bp)->b_lock, PRIBIO + 4, buf_wmesg, 0, 0) 271/* 272 * 273 * Get a lock sleeping non-interruptably until it becomes available. 274 */ 275#define BUF_LOCK(bp, locktype, interlock) \ 276 _lockmgr_args(&(bp)->b_lock, (locktype), (interlock), \ 277 LK_WMESG_DEFAULT, LK_PRIO_DEFAULT, LK_TIMO_DEFAULT, \ 278 LOCK_FILE, LOCK_LINE) 279 280/* 281 * Get a lock sleeping with specified interruptably and timeout. 282 */ 283#define BUF_TIMELOCK(bp, locktype, interlock, wmesg, catch, timo) \ 284 _lockmgr_args(&(bp)->b_lock, (locktype) | LK_TIMELOCK, \ 285 (interlock), (wmesg), (PRIBIO + 4) | (catch), (timo), \ 286 LOCK_FILE, LOCK_LINE) 287 288/* 289 * Release a lock. Only the acquiring process may free the lock unless 290 * it has been handed off to biodone. 291 */ 292#define BUF_UNLOCK(bp) do { \ 293 KASSERT(((bp)->b_flags & B_REMFREE) == 0, \ 294 ("BUF_UNLOCK %p while B_REMFREE is still set.", (bp))); \ 295 \ 296 (void)_lockmgr_args(&(bp)->b_lock, LK_RELEASE, NULL, \ 297 LK_WMESG_DEFAULT, LK_PRIO_DEFAULT, LK_TIMO_DEFAULT, \ 298 LOCK_FILE, LOCK_LINE); \ 299} while (0) 300 301/* 302 * Check if a buffer lock is recursed. 303 */ 304#define BUF_LOCKRECURSED(bp) \ 305 lockmgr_recursed(&(bp)->b_lock) 306 307/* 308 * Check if a buffer lock is currently held. 309 */ 310#define BUF_ISLOCKED(bp) \ 311 lockstatus(&(bp)->b_lock) 312/* 313 * Free a buffer lock. 314 */ 315#define BUF_LOCKFREE(bp) \ 316 lockdestroy(&(bp)->b_lock) 317 318/* 319 * Print informations on a buffer lock. 320 */ 321#define BUF_LOCKPRINTINFO(bp) \ 322 lockmgr_printinfo(&(bp)->b_lock) 323 324/* 325 * Buffer lock assertions. 326 */ 327#if defined(INVARIANTS) && defined(INVARIANT_SUPPORT) 328#define BUF_ASSERT_LOCKED(bp) \ 329 _lockmgr_assert(&(bp)->b_lock, KA_LOCKED, LOCK_FILE, LOCK_LINE) 330#define BUF_ASSERT_SLOCKED(bp) \ 331 _lockmgr_assert(&(bp)->b_lock, KA_SLOCKED, LOCK_FILE, LOCK_LINE) 332#define BUF_ASSERT_XLOCKED(bp) \ 333 _lockmgr_assert(&(bp)->b_lock, KA_XLOCKED, LOCK_FILE, LOCK_LINE) 334#define BUF_ASSERT_UNLOCKED(bp) \ 335 _lockmgr_assert(&(bp)->b_lock, KA_UNLOCKED, LOCK_FILE, LOCK_LINE) 336#define BUF_ASSERT_HELD(bp) 337#define BUF_ASSERT_UNHELD(bp) 338#else 339#define BUF_ASSERT_LOCKED(bp) 340#define BUF_ASSERT_SLOCKED(bp) 341#define BUF_ASSERT_XLOCKED(bp) 342#define BUF_ASSERT_UNLOCKED(bp) 343#define BUF_ASSERT_HELD(bp) 344#define BUF_ASSERT_UNHELD(bp) 345#endif 346 347#ifdef _SYS_PROC_H_ /* Avoid #include <sys/proc.h> pollution */ 348/* 349 * When initiating asynchronous I/O, change ownership of the lock to the 350 * kernel. Once done, the lock may legally released by biodone. The 351 * original owning process can no longer acquire it recursively, but must 352 * wait until the I/O is completed and the lock has been freed by biodone. 353 */ 354#define BUF_KERNPROC(bp) \ 355 _lockmgr_disown(&(bp)->b_lock, LOCK_FILE, LOCK_LINE) 356#endif 357 358/* 359 * Find out if the lock has waiters or not. 360 */ 361#define BUF_LOCKWAITERS(bp) \ 362 lockmgr_waiters(&(bp)->b_lock) 363 364#endif /* _KERNEL */ 365 366struct buf_queue_head { 367 TAILQ_HEAD(buf_queue, buf) queue; 368 daddr_t last_pblkno; 369 struct buf *insert_point; 370 struct buf *switch_point; 371}; 372 373/* 374 * This structure describes a clustered I/O. It is stored in the b_saveaddr 375 * field of the buffer on which I/O is done. At I/O completion, cluster 376 * callback uses the structure to parcel I/O's to individual buffers, and 377 * then free's this structure. 378 */ 379struct cluster_save { 380 long bs_bcount; /* Saved b_bcount. */ 381 long bs_bufsize; /* Saved b_bufsize. */ 382 void *bs_saveaddr; /* Saved b_addr. */ 383 int bs_nchildren; /* Number of associated buffers. */ 384 struct buf **bs_children; /* List of associated buffers. */ 385}; 386 387#ifdef _KERNEL 388 389static __inline int 390bwrite(struct buf *bp) 391{ 392 393 KASSERT(bp->b_bufobj != NULL, ("bwrite: no bufobj bp=%p", bp)); 394 KASSERT(bp->b_bufobj->bo_ops != NULL, ("bwrite: no bo_ops bp=%p", bp)); 395 KASSERT(bp->b_bufobj->bo_ops->bop_write != NULL, 396 ("bwrite: no bop_write bp=%p", bp)); 397 return (BO_WRITE(bp->b_bufobj, bp)); 398} 399 400static __inline void 401bstrategy(struct buf *bp) 402{ 403 404 KASSERT(bp->b_bufobj != NULL, ("bstrategy: no bufobj bp=%p", bp)); 405 KASSERT(bp->b_bufobj->bo_ops != NULL, 406 ("bstrategy: no bo_ops bp=%p", bp)); 407 KASSERT(bp->b_bufobj->bo_ops->bop_strategy != NULL, 408 ("bstrategy: no bop_strategy bp=%p", bp)); 409 BO_STRATEGY(bp->b_bufobj, bp); 410} 411 412static __inline void 413buf_start(struct buf *bp) 414{ 415 if (bioops.io_start) 416 (*bioops.io_start)(bp); 417} 418 419static __inline void 420buf_complete(struct buf *bp) 421{ 422 if (bioops.io_complete) 423 (*bioops.io_complete)(bp); 424} 425 426static __inline void 427buf_deallocate(struct buf *bp) 428{ 429 if (bioops.io_deallocate) 430 (*bioops.io_deallocate)(bp); 431 BUF_LOCKFREE(bp); 432} 433 434static __inline int 435buf_countdeps(struct buf *bp, int i) 436{ 437 if (bioops.io_countdeps) 438 return ((*bioops.io_countdeps)(bp, i)); 439 else 440 return (0); 441} 442 443#endif /* _KERNEL */ 444 445/* 446 * Zero out the buffer's data area. 447 */ 448#define clrbuf(bp) { \ 449 bzero((bp)->b_data, (u_int)(bp)->b_bcount); \ 450 (bp)->b_resid = 0; \ 451} 452 453/* 454 * Flags for getblk's last parameter. 455 */ 456#define GB_LOCK_NOWAIT 0x0001 /* Fail if we block on a buf lock. */ 457#define GB_NOCREAT 0x0002 /* Don't create a buf if not found. */ 458#define GB_NOWAIT_BD 0x0004 /* Do not wait for bufdaemon. */ 459#define GB_UNMAPPED 0x0008 /* Do not mmap buffer pages. */ 460#define GB_KVAALLOC 0x0010 /* But allocate KVA. */ 461 462#ifdef _KERNEL 463extern int nbuf; /* The number of buffer headers */ 464extern long maxswzone; /* Max KVA for swap structures */ 465extern long maxbcache; /* Max KVA for buffer cache */ 466extern long runningbufspace; 467extern long hibufspace; 468extern int dirtybufthresh; 469extern int bdwriteskip; 470extern int dirtybufferflushes; 471extern int altbufferflushes; 472extern int buf_maxio; /* nominal maximum I/O for buffer */ 473extern struct buf *buf; /* The buffer headers. */ 474extern char *buffers; /* The buffer contents. */ 475extern int bufpages; /* Number of memory pages in the buffer pool. */ 476extern struct buf *swbuf; /* Swap I/O buffer headers. */ 477extern int nswbuf; /* Number of swap I/O buffer headers. */ 478extern int cluster_pbuf_freecnt; /* Number of pbufs for clusters */ 479extern int vnode_pbuf_freecnt; /* Number of pbufs for vnode pager */ 480extern caddr_t unmapped_buf; 481 482void runningbufwakeup(struct buf *); 483void waitrunningbufspace(void); 484caddr_t kern_vfs_bio_buffer_alloc(caddr_t v, long physmem_est); 485void bufinit(void); 486void bdata2bio(struct buf *bp, struct bio *bip); 487void bwillwrite(void); 488int buf_dirty_count_severe(void); 489void bremfree(struct buf *); 490void bremfreef(struct buf *); /* XXX Force bremfree, only for nfs. */ 491int bread(struct vnode *, daddr_t, int, struct ucred *, struct buf **); 492int bread_gb(struct vnode *, daddr_t, int, struct ucred *, 493 int gbflags, struct buf **); 494void breada(struct vnode *, daddr_t *, int *, int, struct ucred *); 495int breadn(struct vnode *, daddr_t, int, daddr_t *, int *, int, 496 struct ucred *, struct buf **); 497int breadn_flags(struct vnode *, daddr_t, int, daddr_t *, int *, int, 498 struct ucred *, int, struct buf **); 499void bdwrite(struct buf *); 500void bawrite(struct buf *); 501void babarrierwrite(struct buf *); 502int bbarrierwrite(struct buf *); 503void bdirty(struct buf *); 504void bundirty(struct buf *); 505void bufstrategy(struct bufobj *, struct buf *); 506void brelse(struct buf *); 507void bqrelse(struct buf *); 508int vfs_bio_awrite(struct buf *); 509struct buf * getpbuf(int *); 510struct buf *incore(struct bufobj *, daddr_t); 511struct buf *gbincore(struct bufobj *, daddr_t); 512struct buf *getblk(struct vnode *, daddr_t, int, int, int, int); 513struct buf *geteblk(int, int); 514int bufwait(struct buf *); 515int bufwrite(struct buf *); 516void bufdone(struct buf *); 517void bufdone_finish(struct buf *); 518void bd_speedup(void); 519 520int cluster_read(struct vnode *, u_quad_t, daddr_t, long, 521 struct ucred *, long, int, struct buf **); 522int cluster_wbuild(struct vnode *, long, daddr_t, int); 523void cluster_write(struct vnode *, struct buf *, u_quad_t, int); 524int cluster_read_gb(struct vnode *, u_quad_t, daddr_t, long, 525 struct ucred *, long, int, int, struct buf **); 526int cluster_wbuild_gb(struct vnode *, long, daddr_t, int, int); 527void cluster_write_gb(struct vnode *, struct buf *, u_quad_t, int, int); 528void vfs_bio_bzero_buf(struct buf *bp, int base, int size); 529void vfs_bio_set_valid(struct buf *, int base, int size); 530void vfs_bio_clrbuf(struct buf *); 531void vfs_busy_pages(struct buf *, int clear_modify); 532void vfs_unbusy_pages(struct buf *); 533int vmapbuf(struct buf *, int); 534void vunmapbuf(struct buf *); 535void relpbuf(struct buf *, int *); 536void brelvp(struct buf *); 537void bgetvp(struct vnode *, struct buf *); 538void pbgetbo(struct bufobj *bo, struct buf *bp); 539void pbgetvp(struct vnode *, struct buf *); 540void pbrelbo(struct buf *); 541void pbrelvp(struct buf *); 542int allocbuf(struct buf *bp, int size); 543void reassignbuf(struct buf *); 544struct buf *trypbuf(int *); 545void bwait(struct buf *, u_char, const char *); 546void bdone(struct buf *); 547void bpin(struct buf *); 548void bunpin(struct buf *); 549void bunpin_wait(struct buf *); 550 551#endif /* _KERNEL */ 552 553#endif /* !_SYS_BUF_H_ */ 554