1 /* $NetBSD: lfs.c,v 1.75 2020/04/03 19:36:33 joerg Exp $ */
2 /*-
3  * Copyright (c) 2003 The NetBSD Foundation, Inc.
4  * All rights reserved.
5  *
6  * This code is derived from software contributed to The NetBSD Foundation
7  * by Konrad E. Schroder <perseant@hhhh.org>.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
19  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
20  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
21  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
22  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
23  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
24  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
25  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
26  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
27  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28  * POSSIBILITY OF SUCH DAMAGE.
29  */
30 /*
31  * Copyright (c) 1989, 1991, 1993
32  *        The Regents of the University of California.  All rights reserved.
33  * (c) UNIX System Laboratories, Inc.
34  * All or some portions of this file are derived from material licensed
35  * to the University of California by American Telephone and Telegraph
36  * Co. or Unix System Laboratories, Inc. and are reproduced herein with
37  * the permission of UNIX System Laboratories, Inc.
38  *
39  * Redistribution and use in source and binary forms, with or without
40  * modification, are permitted provided that the following conditions
41  * are met:
42  * 1. Redistributions of source code must retain the above copyright
43  *    notice, this list of conditions and the following disclaimer.
44  * 2. Redistributions in binary form must reproduce the above copyright
45  *    notice, this list of conditions and the following disclaimer in the
46  *    documentation and/or other materials provided with the distribution.
47  * 3. Neither the name of the University nor the names of its contributors
48  *    may be used to endorse or promote products derived from this software
49  *    without specific prior written permission.
50  *
51  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
52  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
53  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
54  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
55  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
56  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
57  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
58  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
59  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
60  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
61  * SUCH DAMAGE.
62  *
63  *        @(#)ufs_bmap.c      8.8 (Berkeley) 8/11/95
64  */
65 
66 
67 #include <sys/types.h>
68 #include <sys/param.h>
69 #include <sys/time.h>
70 #include <sys/buf.h>
71 #include <sys/mount.h>
72 
73 #define vnode uvnode
74 #include <ufs/lfs/lfs.h>
75 #include <ufs/lfs/lfs_inode.h>
76 #include <ufs/lfs/lfs_accessors.h>
77 #undef vnode
78 
79 #include <assert.h>
80 #include <err.h>
81 #include <errno.h>
82 #include <stdarg.h>
83 #include <stdbool.h>
84 #include <stdio.h>
85 #include <stdlib.h>
86 #include <string.h>
87 #include <unistd.h>
88 #include <util.h>
89 
90 #include "bufcache.h"
91 #include "extern.h"
92 #include "lfs_user.h"
93 #include "segwrite.h"
94 #include "kernelops.h"
95 
96 #define panic call_panic
97 
98 long dev_bsize = DEV_BSIZE;
99 
100 static int
101 lfs_fragextend(struct uvnode *, int, int, daddr_t, struct ubuf **);
102 
103 int fsdirty = 0;
104 void (*panic_func)(int, const char *, va_list) = my_vpanic;
105 
106 /*
107  * LFS buffer and uvnode operations
108  */
109 
110 int
lfs_vop_strategy(struct ubuf * bp)111 lfs_vop_strategy(struct ubuf * bp)
112 {
113           int count;
114 
115           if (bp->b_flags & B_READ) {
116                     count = kops.ko_pread(bp->b_vp->v_fd, bp->b_data, bp->b_bcount,
117                         bp->b_blkno * dev_bsize);
118                     if (count == bp->b_bcount)
119                               bp->b_flags |= B_DONE;
120           } else {
121                     count = kops.ko_pwrite(bp->b_vp->v_fd, bp->b_data, bp->b_bcount,
122                         bp->b_blkno * dev_bsize);
123                     if (count == 0) {
124                               perror("pwrite");
125                               return -1;
126                     }
127                     bp->b_flags &= ~B_DELWRI;
128                     reassignbuf(bp, bp->b_vp);
129           }
130           return 0;
131 }
132 
133 int
lfs_vop_bwrite(struct ubuf * bp)134 lfs_vop_bwrite(struct ubuf * bp)
135 {
136           struct lfs *fs;
137 
138           fs = bp->b_vp->v_fs;
139           if (!(bp->b_flags & B_DELWRI)) {
140                     lfs_sb_subavail(fs, lfs_btofsb(fs, bp->b_bcount));
141           }
142           bp->b_flags |= B_DELWRI | B_LOCKED;
143           reassignbuf(bp, bp->b_vp);
144           brelse(bp, 0);
145           return 0;
146 }
147 
148 /*
149  * ulfs_bmaparray does the bmap conversion, and if requested returns the
150  * array of logical blocks which must be traversed to get to a block.
151  * Each entry contains the offset into that block that gets you to the
152  * next block and the disk address of the block (if it is assigned).
153  */
154 int
ulfs_bmaparray(struct lfs * fs,struct uvnode * vp,daddr_t bn,daddr_t * bnp,struct indir * ap,int * nump)155 ulfs_bmaparray(struct lfs * fs, struct uvnode * vp, daddr_t bn, daddr_t * bnp, struct indir * ap, int *nump)
156 {
157           struct inode *ip;
158           struct ubuf *bp;
159           struct indir a[ULFS_NIADDR + 1], *xap;
160           daddr_t daddr;
161           daddr_t metalbn;
162           int error, num;
163 
164           ip = VTOI(vp);
165 
166           if (bn >= 0 && bn < ULFS_NDADDR) {
167                     if (nump != NULL)
168                               *nump = 0;
169                     *bnp = LFS_FSBTODB(fs, lfs_dino_getdb(fs, ip->i_din, bn));
170                     if (*bnp == 0)
171                               *bnp = -1;
172                     return (0);
173           }
174           xap = ap == NULL ? a : ap;
175           if (!nump)
176                     nump = &num;
177           if ((error = ulfs_getlbns(fs, vp, bn, xap, nump)) != 0)
178                     return (error);
179 
180           num = *nump;
181 
182           /* Get disk address out of indirect block array */
183           daddr = lfs_dino_getib(fs, ip->i_din, xap->in_off);
184 
185           for (bp = NULL, ++xap; --num; ++xap) {
186                     /* Exit the loop if there is no disk address assigned yet and
187                      * the indirect block isn't in the cache, or if we were
188                      * looking for an indirect block and we've found it. */
189 
190                     metalbn = xap->in_lbn;
191                     if ((daddr == 0 && !incore(vp, metalbn)) || metalbn == bn)
192                               break;
193                     /*
194                      * If we get here, we've either got the block in the cache
195                      * or we have a disk address for it, go fetch it.
196                      */
197                     if (bp)
198                               brelse(bp, 0);
199 
200                     xap->in_exists = 1;
201                     bp = getblk(vp, metalbn, lfs_sb_getbsize(fs));
202 
203                     if (!(bp->b_flags & (B_DONE | B_DELWRI))) {
204                               bp->b_blkno = LFS_FSBTODB(fs, daddr);
205                               bp->b_flags |= B_READ;
206                               VOP_STRATEGY(bp);
207                     }
208                     daddr = lfs_iblock_get(fs, bp->b_data, xap->in_off);
209           }
210           if (bp)
211                     brelse(bp, 0);
212 
213           daddr = LFS_FSBTODB(fs, daddr);
214           *bnp = daddr == 0 ? -1 : daddr;
215           return (0);
216 }
217 
218 /*
219  * Create an array of logical block number/offset pairs which represent the
220  * path of indirect blocks required to access a data block.  The first "pair"
221  * contains the logical block number of the appropriate single, double or
222  * triple indirect block and the offset into the inode indirect block array.
223  * Note, the logical block number of the inode single/double/triple indirect
224  * block appears twice in the array, once with the offset into di_ib and
225  * once with the offset into the page itself.
226  */
227 int
ulfs_getlbns(struct lfs * fs,struct uvnode * vp,daddr_t bn,struct indir * ap,int * nump)228 ulfs_getlbns(struct lfs * fs, struct uvnode * vp, daddr_t bn, struct indir * ap, int *nump)
229 {
230           daddr_t metalbn, realbn;
231           int64_t blockcnt;
232           int lbc;
233           int i, numlevels, off;
234           int lognindir, indir;
235 
236           metalbn = 0;    /* XXXGCC -Wuninitialized [sh3] */
237 
238           if (nump)
239                     *nump = 0;
240           numlevels = 0;
241           realbn = bn;
242           if (bn < 0)
243                     bn = -bn;
244 
245           lognindir = -1;
246           for (indir = lfs_sb_getnindir(fs); indir; indir >>= 1)
247                     ++lognindir;
248 
249           /* Determine the number of levels of indirection.  After this loop is
250            * done, blockcnt indicates the number of data blocks possible at the
251            * given level of indirection, and ULFS_NIADDR - i is the number of levels
252            * of indirection needed to locate the requested block. */
253 
254           bn -= ULFS_NDADDR;
255           for (lbc = 0, i = ULFS_NIADDR;; i--, bn -= blockcnt) {
256                     if (i == 0)
257                               return (EFBIG);
258 
259                     lbc += lognindir;
260                     blockcnt = (int64_t) 1 << lbc;
261 
262                     if (bn < blockcnt)
263                               break;
264           }
265 
266           /* Calculate the address of the first meta-block. */
267           metalbn = -((realbn >= 0 ? realbn : -realbn) - bn + ULFS_NIADDR - i);
268 
269           /* At each iteration, off is the offset into the bap array which is an
270            * array of disk addresses at the current level of indirection. The
271            * logical block number and the offset in that block are stored into
272            * the argument array. */
273           ap->in_lbn = metalbn;
274           ap->in_off = off = ULFS_NIADDR - i;
275           ap->in_exists = 0;
276           ap++;
277           for (++numlevels; i <= ULFS_NIADDR; i++) {
278                     /* If searching for a meta-data block, quit when found. */
279                     if (metalbn == realbn)
280                               break;
281 
282                     lbc -= lognindir;
283                     /*blockcnt = (int64_t) 1 << lbc;*/
284                     off = (bn >> lbc) & (lfs_sb_getnindir(fs) - 1);
285 
286                     ++numlevels;
287                     ap->in_lbn = metalbn;
288                     ap->in_off = off;
289                     ap->in_exists = 0;
290                     ++ap;
291 
292                     metalbn -= -1 + (off << lbc);
293           }
294           if (nump)
295                     *nump = numlevels;
296           return (0);
297 }
298 
299 int
lfs_vop_bmap(struct uvnode * vp,daddr_t lbn,daddr_t * daddrp)300 lfs_vop_bmap(struct uvnode * vp, daddr_t lbn, daddr_t * daddrp)
301 {
302           return ulfs_bmaparray(vp->v_fs, vp, lbn, daddrp, NULL, NULL);
303 }
304 
305 /* Search a block for a specific dinode. */
306 union lfs_dinode *
lfs_ifind(struct lfs * fs,ino_t ino,struct ubuf * bp)307 lfs_ifind(struct lfs *fs, ino_t ino, struct ubuf *bp)
308 {
309           union lfs_dinode *ldip;
310           unsigned i, num;
311 
312           num = LFS_INOPB(fs);
313 
314           /*
315            * Read the inode block backwards, since later versions of the
316            * inode will supercede earlier ones.  Though it is unlikely, it is
317            * possible that the same inode will appear in the same inode block.
318            */
319           for (i = num; i-- > 0; ) {
320                     ldip = DINO_IN_BLOCK(fs, bp->b_data, i);
321                     if (lfs_dino_getinumber(fs, ldip) == ino)
322                               return (ldip);
323           }
324           return NULL;
325 }
326 
327 /*
328  * lfs_raw_vget makes us a new vnode from the inode at the given disk address.
329  * XXX it currently loses atime information.
330  */
331 struct uvnode *
lfs_raw_vget(struct lfs * fs,ino_t ino,int fd,daddr_t daddr)332 lfs_raw_vget(struct lfs * fs, ino_t ino, int fd, daddr_t daddr)
333 {
334           struct uvnode *vp;
335           struct inode *ip;
336           union lfs_dinode *dip;
337           struct ubuf *bp;
338           int i, hash;
339 
340           vp = ecalloc(1, sizeof(*vp));
341           vp->v_fd = fd;
342           vp->v_fs = fs;
343           vp->v_usecount = 0;
344           vp->v_strategy_op = lfs_vop_strategy;
345           vp->v_bwrite_op = lfs_vop_bwrite;
346           vp->v_bmap_op = lfs_vop_bmap;
347           LIST_INIT(&vp->v_cleanblkhd);
348           LIST_INIT(&vp->v_dirtyblkhd);
349 
350           ip = ecalloc(1, sizeof(*ip));
351 
352           ip->i_din = dip = ecalloc(1, sizeof(*dip));
353 
354           /* Initialize the inode -- from lfs_vcreate. */
355           ip->inode_ext.lfs = ecalloc(1, sizeof(*ip->inode_ext.lfs));
356           vp->v_data = ip;
357           /* ip->i_vnode = vp; */
358           ip->i_lockf = 0;
359           ip->i_state = 0;
360 
361           /* Load inode block and find inode */
362           if (daddr > 0) {
363                     bread(fs->lfs_devvp, LFS_FSBTODB(fs, daddr), lfs_sb_getibsize(fs),
364                         0, &bp);
365                     bp->b_flags |= B_AGE;
366                     dip = lfs_ifind(fs, ino, bp);
367                     if (dip == NULL) {
368                               brelse(bp, 0);
369                               free(ip->i_din);
370                               free(ip->inode_ext.lfs);
371                               free(ip);
372                               free(vp);
373                               return NULL;
374                     }
375                     lfs_copy_dinode(fs, ip->i_din, dip);
376                     brelse(bp, 0);
377           }
378           ip->i_number = ino;
379           /* ip->i_devvp = fs->lfs_devvp; */
380           ip->i_lfs = fs;
381 
382           ip->i_lfs_effnblks = lfs_dino_getblocks(fs, ip->i_din);
383           ip->i_lfs_osize = lfs_dino_getsize(fs, ip->i_din);
384 #if 0
385           if (lfs_sb_getversion(fs) > 1) {
386                     lfs_dino_setatime(fs, ip->i_din, ts.tv_sec);
387                     lfs_dino_setatimensec(fs, ip->i_din, ts.tv_nsec);
388           }
389 #endif
390 
391           memset(ip->i_lfs_fragsize, 0, ULFS_NDADDR * sizeof(*ip->i_lfs_fragsize));
392           for (i = 0; i < ULFS_NDADDR; i++)
393                     if (lfs_dino_getdb(fs, ip->i_din, i) != 0)
394                               ip->i_lfs_fragsize[i] = lfs_blksize(fs, ip, i);
395 
396           ++nvnodes;
397           hash = ((int)(intptr_t)fs + ino) & (VNODE_HASH_MAX - 1);
398           LIST_INSERT_HEAD(&getvnodelist[hash], vp, v_getvnodes);
399           LIST_INSERT_HEAD(&vnodelist, vp, v_mntvnodes);
400 
401           return vp;
402 }
403 
404 static struct uvnode *
lfs_vget(void * vfs,ino_t ino)405 lfs_vget(void *vfs, ino_t ino)
406 {
407           struct lfs *fs = (struct lfs *)vfs;
408           daddr_t daddr;
409           struct ubuf *bp;
410           IFILE *ifp;
411 
412           LFS_IENTRY(ifp, fs, ino, bp);
413           daddr = lfs_if_getdaddr(fs, ifp);
414           brelse(bp, 0);
415           if (daddr <= 0 || lfs_dtosn(fs, daddr) >= lfs_sb_getnseg(fs))
416                     return NULL;
417           return lfs_raw_vget(fs, ino, fs->lfs_ivnode->v_fd, daddr);
418 }
419 
420 /*
421  * Check superblock magic number and checksum.
422  * Sets lfs_is64 and lfs_dobyteswap.
423  */
424 static int
check_sb(struct lfs * fs)425 check_sb(struct lfs *fs)
426 {
427           u_int32_t checksum;
428           u_int32_t magic;
429 
430           /* we can read the magic out of either the 32-bit or 64-bit dlfs */
431           magic = fs->lfs_dlfs_u.u_32.dlfs_magic;
432 
433           switch (magic) {
434               case LFS_MAGIC:
435                     fs->lfs_is64 = false;
436                     fs->lfs_dobyteswap = false;
437                     break;
438               case LFS_MAGIC_SWAPPED:
439                     fs->lfs_is64 = false;
440                     fs->lfs_dobyteswap = true;
441                     break;
442               case LFS64_MAGIC:
443                     fs->lfs_is64 = true;
444                     fs->lfs_dobyteswap = false;
445                     break;
446               case LFS64_MAGIC_SWAPPED:
447                     fs->lfs_is64 = true;
448                     fs->lfs_dobyteswap = true;
449                     break;
450               default:
451                     printf("Superblock magic number (0x%lx) does not match "
452                            "expected 0x%lx\n", (unsigned long) magic,
453                            (unsigned long) LFS_MAGIC);
454                     return 1;
455           }
456 
457           /* checksum */
458           checksum = lfs_sb_cksum(fs);
459           if (lfs_sb_getcksum(fs) != checksum) {
460                     printf("Superblock checksum (%lx) does not match computed checksum (%lx)\n",
461                         (unsigned long) lfs_sb_getcksum(fs), (unsigned long) checksum);
462                     return 1;
463           }
464           return 0;
465 }
466 
467 /* Initialize LFS library; load superblocks and choose which to use. */
468 struct lfs *
lfs_init(int devfd,daddr_t sblkno,daddr_t idaddr,int dummy_read,int debug)469 lfs_init(int devfd, daddr_t sblkno, daddr_t idaddr, int dummy_read, int debug)
470 {
471           struct uvnode *devvp;
472           struct ubuf *bp;
473           int tryalt;
474           struct lfs *fs, *altfs;
475 
476           vfs_init();
477 
478           devvp = ecalloc(1, sizeof(*devvp));
479           devvp->v_fs = NULL;
480           devvp->v_fd = devfd;
481           devvp->v_strategy_op = raw_vop_strategy;
482           devvp->v_bwrite_op = raw_vop_bwrite;
483           devvp->v_bmap_op = raw_vop_bmap;
484           LIST_INIT(&devvp->v_cleanblkhd);
485           LIST_INIT(&devvp->v_dirtyblkhd);
486 
487           tryalt = 0;
488           if (dummy_read) {
489                     if (sblkno == 0)
490                               sblkno = LFS_LABELPAD / dev_bsize;
491                     fs = ecalloc(1, sizeof(*fs));
492                     fs->lfs_devvp = devvp;
493           } else {
494                     if (sblkno == 0) {
495                               sblkno = LFS_LABELPAD / dev_bsize;
496                               tryalt = 1;
497                     } else if (debug) {
498                               printf("No -b flag given, not attempting to verify checkpoint\n");
499                     }
500 
501                     dev_bsize = DEV_BSIZE;
502 
503                     (void)bread(devvp, sblkno, LFS_SBPAD, 0, &bp);
504                     fs = ecalloc(1, sizeof(*fs));
505                     __CTASSERT(sizeof(struct dlfs) == sizeof(struct dlfs64));
506                     memcpy(&fs->lfs_dlfs_u, bp->b_data, sizeof(struct dlfs));
507                     fs->lfs_devvp = devvp;
508                     bp->b_flags |= B_INVAL;
509                     brelse(bp, 0);
510 
511                     dev_bsize = lfs_sb_getfsize(fs) >> lfs_sb_getfsbtodb(fs);
512 
513                     if (tryalt) {
514                               (void)bread(devvp, LFS_FSBTODB(fs, lfs_sb_getsboff(fs, 1)),
515                               LFS_SBPAD, 0, &bp);
516                               altfs = ecalloc(1, sizeof(*altfs));
517                               memcpy(&altfs->lfs_dlfs_u, bp->b_data,
518                                      sizeof(struct dlfs));
519                               altfs->lfs_devvp = devvp;
520                               bp->b_flags |= B_INVAL;
521                               brelse(bp, 0);
522 
523                               if (check_sb(fs) || lfs_sb_getidaddr(fs) <= 0) {
524                                         if (debug)
525                                                   printf("Primary superblock is no good, using first alternate\n");
526                                         free(fs);
527                                         fs = altfs;
528                               } else {
529                                         /* If both superblocks check out, try verification */
530                                         if (check_sb(altfs)) {
531                                                   if (debug)
532                                                             printf("First alternate superblock is no good, using primary\n");
533                                                   free(altfs);
534                                         } else {
535                                                   if (lfs_verify(fs, altfs, devvp, debug) == fs) {
536                                                             free(altfs);
537                                                   } else {
538                                                             free(fs);
539                                                             fs = altfs;
540                                                   }
541                                         }
542                               }
543                     }
544                     if (check_sb(fs)) {
545                               free(fs);
546                               return NULL;
547                     }
548           }
549 
550           /* Compatibility */
551           if (lfs_sb_getversion(fs) < 2) {
552                     lfs_sb_setsumsize(fs, LFS_V1_SUMMARY_SIZE);
553                     lfs_sb_setibsize(fs, lfs_sb_getbsize(fs));
554                     lfs_sb_sets0addr(fs, lfs_sb_getsboff(fs, 0));
555                     lfs_sb_settstamp(fs, lfs_sb_getotstamp(fs));
556                     lfs_sb_setfsbtodb(fs, 0);
557           }
558 
559           if (!dummy_read) {
560                     fs->lfs_suflags = emalloc(2 * sizeof(u_int32_t *));
561                     fs->lfs_suflags[0] = emalloc(lfs_sb_getnseg(fs) * sizeof(u_int32_t));
562                     fs->lfs_suflags[1] = emalloc(lfs_sb_getnseg(fs) * sizeof(u_int32_t));
563           }
564 
565           if (idaddr == 0)
566                     idaddr = lfs_sb_getidaddr(fs);
567           else
568                     lfs_sb_setidaddr(fs, idaddr);
569           /* NB: If dummy_read!=0, idaddr==0 here so we get a fake inode. */
570           fs->lfs_ivnode = lfs_raw_vget(fs, LFS_IFILE_INUM,
571                     devvp->v_fd, idaddr);
572           if (fs->lfs_ivnode == NULL)
573                     return NULL;
574 
575           register_vget((void *)fs, lfs_vget);
576 
577           return fs;
578 }
579 
580 /*
581  * Check partial segment validity between fs->lfs_offset and the given goal.
582  *
583  * If goal == 0, just keep on going until the segments stop making sense,
584  * and return the address of the last valid partial segment.
585  *
586  * If goal != 0, return the address of the first partial segment that failed,
587  * or "goal" if we reached it without failure (the partial segment *at* goal
588  * need not be valid).
589  */
590 daddr_t
try_verify(struct lfs * osb,struct uvnode * devvp,daddr_t goal,int debug)591 try_verify(struct lfs *osb, struct uvnode *devvp, daddr_t goal, int debug)
592 {
593           daddr_t daddr, odaddr;
594           SEGSUM *sp;
595           int i, bc, hitclean;
596           struct ubuf *bp;
597           daddr_t nodirop_daddr;
598           u_int64_t serial;
599 
600           bc = 0;
601           hitclean = 0;
602           odaddr = -1;
603           daddr = lfs_sb_getoffset(osb);
604           nodirop_daddr = daddr;
605           serial = lfs_sb_getserial(osb);
606           while (daddr != goal) {
607                     /*
608                      * Don't mistakenly read a superblock, if there is one here.
609                      */
610                     if (lfs_sntod(osb, lfs_dtosn(osb, daddr)) == daddr) {
611                               if (daddr == lfs_sb_gets0addr(osb))
612                                         daddr += lfs_btofsb(osb, LFS_LABELPAD);
613                               for (i = 0; i < LFS_MAXNUMSB; i++) {
614                                         /* XXX dholland 20150828 I think this is wrong */
615                                         if (lfs_sb_getsboff(osb, i) < daddr)
616                                                   break;
617                                         if (lfs_sb_getsboff(osb, i) == daddr)
618                                                   daddr += lfs_btofsb(osb, LFS_SBPAD);
619                               }
620                     }
621 
622                     /* Read in summary block */
623                     bread(devvp, LFS_FSBTODB(osb, daddr), lfs_sb_getsumsize(osb),
624                         0, &bp);
625                     sp = (SEGSUM *)bp->b_data;
626 
627                     /*
628                      * Check for a valid segment summary belonging to our fs.
629                      */
630                     if (lfs_ss_getmagic(osb, sp) != SS_MAGIC ||
631                         lfs_ss_getident(osb, sp) != lfs_sb_getident(osb) ||
632                         lfs_ss_getserial(osb, sp) < serial ||         /* XXX strengthen this */
633                         lfs_ss_getsumsum(osb, sp) !=
634                                 cksum((char *)sp + lfs_ss_getsumstart(osb),
635                                           lfs_sb_getsumsize(osb) - lfs_ss_getsumstart(osb))) {
636                               brelse(bp, 0);
637                               if (debug) {
638                                         if (lfs_ss_getmagic(osb, sp) != SS_MAGIC)
639                                                   pwarn("pseg at 0x%jx: "
640                                                         "wrong magic number\n",
641                                                         (uintmax_t)daddr);
642                                         else if (lfs_ss_getident(osb, sp) != lfs_sb_getident(osb))
643                                                   pwarn("pseg at 0x%jx: "
644                                                         "expected ident %jx, got %jx\n",
645                                                         (uintmax_t)daddr,
646                                                         (uintmax_t)lfs_ss_getident(osb, sp),
647                                                         (uintmax_t)lfs_sb_getident(osb));
648                                         else if (lfs_ss_getserial(osb, sp) >= serial)
649                                                   pwarn("pseg at 0x%jx: "
650                                                         "serial %d < %d\n",
651                                                         (uintmax_t)daddr,
652                                                         (int)lfs_ss_getserial(osb, sp), (int)serial);
653                                         else
654                                                   pwarn("pseg at 0x%jx: "
655                                                         "summary checksum wrong\n",
656                                                         (uintmax_t)daddr);
657                               }
658                               break;
659                     }
660                     if (debug && lfs_ss_getserial(osb, sp) != serial)
661                               pwarn("warning, serial=%d ss_serial=%d\n",
662                                         (int)serial, (int)lfs_ss_getserial(osb, sp));
663                     ++serial;
664                     bc = check_summary(osb, sp, daddr, debug, devvp, NULL);
665                     if (bc == 0) {
666                               brelse(bp, 0);
667                               break;
668                     }
669                     if (debug)
670                               pwarn("summary good: 0x%x/%d\n", (uintmax_t)daddr,
671                                     (int)lfs_ss_getserial(osb, sp));
672                     assert (bc > 0);
673                     odaddr = daddr;
674                     daddr += lfs_btofsb(osb, lfs_sb_getsumsize(osb) + bc);
675                     if (lfs_dtosn(osb, odaddr) != lfs_dtosn(osb, daddr) ||
676                         lfs_dtosn(osb, daddr) != lfs_dtosn(osb, daddr +
677                               lfs_btofsb(osb, lfs_sb_getsumsize(osb) + lfs_sb_getbsize(osb)) - 1)) {
678                               daddr = lfs_ss_getnext(osb, sp);
679                     }
680 
681                     /*
682                      * Check for the beginning and ending of a sequence of
683                      * dirops.  Writes from the cleaner never involve new
684                      * information, and are always checkpoints; so don't try
685                      * to roll forward through them.  Likewise, psegs written
686                      * by a previous roll-forward attempt are not interesting.
687                      */
688                     if (lfs_ss_getflags(osb, sp) & (SS_CLEAN | SS_RFW))
689                               hitclean = 1;
690                     if (hitclean == 0 && (lfs_ss_getflags(osb, sp) & SS_CONT) == 0)
691                               nodirop_daddr = daddr;
692 
693                     brelse(bp, 0);
694           }
695 
696           if (goal == 0)
697                     return nodirop_daddr;
698           else
699                     return daddr;
700 }
701 
702 /* Use try_verify to check whether the newer superblock is valid. */
703 struct lfs *
lfs_verify(struct lfs * sb0,struct lfs * sb1,struct uvnode * devvp,int debug)704 lfs_verify(struct lfs *sb0, struct lfs *sb1, struct uvnode *devvp, int debug)
705 {
706           daddr_t daddr;
707           struct lfs *osb, *nsb;
708 
709           /*
710            * Verify the checkpoint of the newer superblock,
711            * if the timestamp/serial number of the two superblocks is
712            * different.
713            */
714 
715           osb = NULL;
716           if (debug)
717                     pwarn("sb0 %ju, sb1 %ju",
718                           (uintmax_t) lfs_sb_getserial(sb0),
719                           (uintmax_t) lfs_sb_getserial(sb1));
720 
721           if ((lfs_sb_getversion(sb0) == 1 &&
722                     lfs_sb_getotstamp(sb0) != lfs_sb_getotstamp(sb1)) ||
723               (lfs_sb_getversion(sb0) > 1 &&
724                     lfs_sb_getserial(sb0) != lfs_sb_getserial(sb1))) {
725                     if (lfs_sb_getversion(sb0) == 1) {
726                               if (lfs_sb_getotstamp(sb0) > lfs_sb_getotstamp(sb1)) {
727                                         osb = sb1;
728                                         nsb = sb0;
729                               } else {
730                                         osb = sb0;
731                                         nsb = sb1;
732                               }
733                     } else {
734                               if (lfs_sb_getserial(sb0) > lfs_sb_getserial(sb1)) {
735                                         osb = sb1;
736                                         nsb = sb0;
737                               } else {
738                                         osb = sb0;
739                                         nsb = sb1;
740                               }
741                     }
742                     if (debug) {
743                               printf("Attempting to verify newer checkpoint...");
744                               fflush(stdout);
745                     }
746                     daddr = try_verify(osb, devvp, lfs_sb_getoffset(nsb), debug);
747 
748                     if (debug)
749                               printf("done.\n");
750                     if (daddr == lfs_sb_getoffset(nsb)) {
751                               pwarn("** Newer checkpoint verified; recovered %jd seconds of data\n",
752                                   (intmax_t)(lfs_sb_gettstamp(nsb) - lfs_sb_gettstamp(osb)));
753                               sbdirty();
754                     } else {
755                               pwarn("** Newer checkpoint invalid; lost %jd seconds of data\n", (intmax_t)(lfs_sb_gettstamp(nsb) - lfs_sb_gettstamp(osb)));
756                     }
757                     return (daddr == lfs_sb_getoffset(nsb) ? nsb : osb);
758           }
759           /* Nothing to check */
760           return osb;
761 }
762 
763 /* Verify a partial-segment summary; return the number of bytes on disk. */
764 int
check_summary(struct lfs * fs,SEGSUM * sp,daddr_t pseg_addr,int debug,struct uvnode * devvp,void (func (daddr_t,FINFO *)))765 check_summary(struct lfs *fs, SEGSUM *sp, daddr_t pseg_addr, int debug,
766                 struct uvnode *devvp, void (func(daddr_t, FINFO *)))
767 {
768           FINFO *fp;
769           int bc;                       /* Bytes in partial segment */
770           int nblocks;
771           daddr_t daddr;
772           IINFO *iibase, *iip;
773           struct ubuf *bp;
774           int i, j, k, datac, len;
775           lfs_checkword *datap;
776           u_int32_t ccksum;
777 
778           /* We've already checked the sumsum, just do the data bounds and sum */
779 
780           /* Count the blocks. */
781           nblocks = howmany(lfs_ss_getninos(fs, sp), LFS_INOPB(fs));
782           bc = nblocks << (lfs_sb_getversion(fs) > 1 ? lfs_sb_getffshift(fs) : lfs_sb_getbshift(fs));
783           assert(bc >= 0);
784 
785           fp = SEGSUM_FINFOBASE(fs, sp);
786           for (i = 0; i < lfs_ss_getnfinfo(fs, sp); i++) {
787                     nblocks += lfs_fi_getnblocks(fs, fp);
788                     bc += lfs_fi_getlastlength(fs, fp) + ((lfs_fi_getnblocks(fs, fp) - 1)
789                                                      << lfs_sb_getbshift(fs));
790                     assert(bc >= 0);
791                     fp = NEXT_FINFO(fs, fp);
792                     if (((char *)fp) - (char *)sp > lfs_sb_getsumsize(fs))
793                               return 0;
794           }
795           datap = emalloc(nblocks * sizeof(*datap));
796           datac = 0;
797 
798           iibase = SEGSUM_IINFOSTART(fs, sp);
799 
800           iip = iibase;
801           daddr = pseg_addr + lfs_btofsb(fs, lfs_sb_getsumsize(fs));
802           fp = SEGSUM_FINFOBASE(fs, sp);
803           for (i = 0, j = 0;
804                i < lfs_ss_getnfinfo(fs, sp) || j < howmany(lfs_ss_getninos(fs, sp), LFS_INOPB(fs)); i++) {
805                     if (i >= lfs_ss_getnfinfo(fs, sp) && lfs_ii_getblock(fs, iip) != daddr) {
806                               pwarn("Not enough inode blocks in pseg at 0x%jx: "
807                                     "found %d, wanted %d\n",
808                                     pseg_addr, j, howmany(lfs_ss_getninos(fs, sp),
809                                                                 LFS_INOPB(fs)));
810                               if (debug)
811                                         pwarn("iip=0x%jx, daddr=0x%jx\n",
812                                             (uintmax_t)lfs_ii_getblock(fs, iip),
813                                             (intmax_t)daddr);
814                               break;
815                     }
816                     while (j < howmany(lfs_ss_getninos(fs, sp), LFS_INOPB(fs)) && lfs_ii_getblock(fs, iip) == daddr) {
817                               bread(devvp, LFS_FSBTODB(fs, daddr), lfs_sb_getibsize(fs),
818                                   0, &bp);
819                               datap[datac++] = ((lfs_checkword *)bp->b_data)[0];
820                               brelse(bp, 0);
821 
822                               ++j;
823                               daddr += lfs_btofsb(fs, lfs_sb_getibsize(fs));
824                               iip = NEXTLOWER_IINFO(fs, iip);
825                     }
826                     if (i < lfs_ss_getnfinfo(fs, sp)) {
827                               if (func)
828                                         func(daddr, fp);
829                               for (k = 0; k < lfs_fi_getnblocks(fs, fp); k++) {
830                                         len = (k == lfs_fi_getnblocks(fs, fp) - 1 ?
831                                                lfs_fi_getlastlength(fs, fp)
832                                                : lfs_sb_getbsize(fs));
833                                         bread(devvp, LFS_FSBTODB(fs, daddr), len,
834                                             0, &bp);
835                                         datap[datac++] = ((lfs_checkword *)bp->b_data)[0];
836                                         brelse(bp, 0);
837                                         daddr += lfs_btofsb(fs, len);
838                               }
839                               fp = NEXT_FINFO(fs, fp);
840                     }
841           }
842 
843           if (datac != nblocks) {
844                     pwarn("Partial segment at 0x%jx expected %d blocks counted %d\n",
845                         (intmax_t)pseg_addr, nblocks, datac);
846           }
847           ccksum = cksum(datap, nblocks * sizeof(datap[0]));
848           /* Check the data checksum */
849           if (ccksum != lfs_ss_getdatasum(fs, sp)) {
850                     pwarn("Partial segment at 0x%jx data checksum"
851                           " mismatch: given 0x%x, computed 0x%x\n",
852                           (uintmax_t)pseg_addr, lfs_ss_getdatasum(fs, sp), ccksum);
853                     free(datap);
854                     return 0;
855           }
856           free(datap);
857           assert(bc >= 0);
858           return bc;
859 }
860 
861 /* print message and exit */
862 void
my_vpanic(int fatal,const char * fmt,va_list ap)863 my_vpanic(int fatal, const char *fmt, va_list ap)
864 {
865         (void) vprintf(fmt, ap);
866           exit(8);
867 }
868 
869 void
call_panic(const char * fmt,...)870 call_panic(const char *fmt, ...)
871 {
872           va_list ap;
873 
874           va_start(ap, fmt);
875         panic_func(1, fmt, ap);
876           va_end(ap);
877 }
878 
879 /* Allocate a new inode. */
880 struct uvnode *
lfs_valloc(struct lfs * fs,ino_t ino)881 lfs_valloc(struct lfs *fs, ino_t ino)
882 {
883           struct ubuf *bp, *cbp;
884           IFILE *ifp;
885           ino_t new_ino;
886           int error;
887           CLEANERINFO *cip;
888 
889           /* Get the head of the freelist. */
890           LFS_GET_HEADFREE(fs, cip, cbp, &new_ino);
891 
892           /*
893            * Remove the inode from the free list and write the new start
894            * of the free list into the superblock.
895            */
896           LFS_IENTRY(ifp, fs, new_ino, bp);
897           if (lfs_if_getdaddr(fs, ifp) != LFS_UNUSED_DADDR)
898                     panic("lfs_valloc: inuse inode %d on the free list", new_ino);
899           LFS_PUT_HEADFREE(fs, cip, cbp, lfs_if_getnextfree(fs, ifp));
900 
901           brelse(bp, 0);
902 
903           /* Extend IFILE so that the next lfs_valloc will succeed. */
904           if (lfs_sb_getfreehd(fs) == LFS_UNUSED_INUM) {
905                     if ((error = extend_ifile(fs)) != 0) {
906                               LFS_PUT_HEADFREE(fs, cip, cbp, new_ino);
907                               return NULL;
908                     }
909           }
910 
911           /* Set superblock modified bit and increment file count. */
912         sbdirty();
913           lfs_sb_addnfiles(fs, 1);
914 
915         return lfs_raw_vget(fs, ino, fs->lfs_devvp->v_fd, 0x0);
916 }
917 
918 #ifdef IN_FSCK_LFS
919 void reset_maxino(ino_t);
920 #endif
921 
922 /*
923  * Add a new block to the Ifile, to accommodate future file creations.
924  */
925 int
extend_ifile(struct lfs * fs)926 extend_ifile(struct lfs *fs)
927 {
928           struct uvnode *vp;
929           struct inode *ip;
930           IFILE64 *ifp64;
931           IFILE32 *ifp32;
932           IFILE_V1 *ifp_v1;
933           struct ubuf *bp, *cbp;
934           daddr_t i, blkno, max;
935           ino_t oldlast;
936           CLEANERINFO *cip;
937 
938           vp = fs->lfs_ivnode;
939           ip = VTOI(vp);
940           blkno = lfs_lblkno(fs, lfs_dino_getsize(fs, ip->i_din));
941 
942           lfs_balloc(vp, lfs_dino_getsize(fs, ip->i_din), lfs_sb_getbsize(fs), &bp);
943           lfs_dino_setsize(fs, ip->i_din,
944               lfs_dino_getsize(fs, ip->i_din) + lfs_sb_getbsize(fs));
945           ip->i_state |= IN_MODIFIED;
946 
947           i = (blkno - lfs_sb_getsegtabsz(fs) - lfs_sb_getcleansz(fs)) *
948                     lfs_sb_getifpb(fs);
949           LFS_GET_HEADFREE(fs, cip, cbp, &oldlast);
950           LFS_PUT_HEADFREE(fs, cip, cbp, i);
951           max = i + lfs_sb_getifpb(fs);
952           lfs_sb_subbfree(fs, lfs_btofsb(fs, lfs_sb_getbsize(fs)));
953 
954           if (fs->lfs_is64) {
955                     for (ifp64 = (IFILE64 *)bp->b_data; i < max; ++ifp64) {
956                               ifp64->if_version = 1;
957                               ifp64->if_daddr = LFS_UNUSED_DADDR;
958                               ifp64->if_nextfree = ++i;
959                     }
960                     ifp64--;
961                     ifp64->if_nextfree = oldlast;
962           } else if (lfs_sb_getversion(fs) > 1) {
963                     for (ifp32 = (IFILE32 *)bp->b_data; i < max; ++ifp32) {
964                               ifp32->if_version = 1;
965                               ifp32->if_daddr = LFS_UNUSED_DADDR;
966                               ifp32->if_nextfree = ++i;
967                     }
968                     ifp32--;
969                     ifp32->if_nextfree = oldlast;
970           } else {
971                     for (ifp_v1 = (IFILE_V1 *)bp->b_data; i < max; ++ifp_v1) {
972                               ifp_v1->if_version = 1;
973                               ifp_v1->if_daddr = LFS_UNUSED_DADDR;
974                               ifp_v1->if_nextfree = ++i;
975                     }
976                     ifp_v1--;
977                     ifp_v1->if_nextfree = oldlast;
978           }
979           LFS_PUT_TAILFREE(fs, cip, cbp, max - 1);
980 
981           LFS_BWRITE_LOG(bp);
982 
983 #ifdef IN_FSCK_LFS
984           reset_maxino(((lfs_dino_getsize(fs, ip->i_din) >> lfs_sb_getbshift(fs))
985                           - lfs_sb_getsegtabsz(fs)
986                           - lfs_sb_getcleansz(fs)) * lfs_sb_getifpb(fs));
987 #endif
988           return 0;
989 }
990 
991 /*
992  * Allocate a block, and to inode and filesystem block accounting for it
993  * and for any indirect blocks the may need to be created in order for
994  * this block to be created.
995  *
996  * Blocks which have never been accounted for (i.e., which "do not exist")
997  * have disk address 0, which is translated by ulfs_bmap to the special value
998  * UNASSIGNED == -1, as in the historical ULFS.
999  *
1000  * Blocks which have been accounted for but which have not yet been written
1001  * to disk are given the new special disk address UNWRITTEN == -2, so that
1002  * they can be differentiated from completely new blocks.
1003  */
1004 int
lfs_balloc(struct uvnode * vp,off_t startoffset,int iosize,struct ubuf ** bpp)1005 lfs_balloc(struct uvnode *vp, off_t startoffset, int iosize, struct ubuf **bpp)
1006 {
1007           int offset;
1008           daddr_t daddr, idaddr;
1009           struct ubuf *ibp, *bp;
1010           struct inode *ip;
1011           struct lfs *fs;
1012           struct indir indirs[ULFS_NIADDR+2], *idp;
1013           daddr_t   lbn, lastblock;
1014           int bcount;
1015           int error, frags, i, nsize, osize, num;
1016 
1017           ip = VTOI(vp);
1018           fs = ip->i_lfs;
1019           offset = lfs_blkoff(fs, startoffset);
1020           lbn = lfs_lblkno(fs, startoffset);
1021 
1022           /*
1023            * Three cases: it's a block beyond the end of file, it's a block in
1024            * the file that may or may not have been assigned a disk address or
1025            * we're writing an entire block.
1026            *
1027            * Note, if the daddr is UNWRITTEN, the block already exists in
1028            * the cache (it was read or written earlier).    If so, make sure
1029            * we don't count it as a new block or zero out its contents. If
1030            * it did not, make sure we allocate any necessary indirect
1031            * blocks.
1032            *
1033            * If we are writing a block beyond the end of the file, we need to
1034            * check if the old last block was a fragment.    If it was, we need
1035            * to rewrite it.
1036            */
1037 
1038           if (bpp)
1039                     *bpp = NULL;
1040 
1041           /* Check for block beyond end of file and fragment extension needed. */
1042           lastblock = lfs_lblkno(fs, lfs_dino_getsize(fs, ip->i_din));
1043           if (lastblock < ULFS_NDADDR && lastblock < lbn) {
1044                     osize = lfs_blksize(fs, ip, lastblock);
1045                     if (osize < lfs_sb_getbsize(fs) && osize > 0) {
1046                               if ((error = lfs_fragextend(vp, osize, lfs_sb_getbsize(fs),
1047                                                                 lastblock,
1048                                                                 (bpp ? &bp : NULL))))
1049                                         return (error);
1050                               lfs_dino_setsize(fs, ip->i_din, (lastblock + 1) * lfs_sb_getbsize(fs));
1051                               ip->i_state |= IN_CHANGE | IN_UPDATE;
1052                               if (bpp)
1053                                         (void) VOP_BWRITE(bp);
1054                     }
1055           }
1056 
1057           /*
1058            * If the block we are writing is a direct block, it's the last
1059            * block in the file, and offset + iosize is less than a full
1060            * block, we can write one or more fragments.  There are two cases:
1061            * the block is brand new and we should allocate it the correct
1062            * size or it already exists and contains some fragments and
1063            * may need to extend it.
1064            */
1065           if (lbn < ULFS_NDADDR && lfs_lblkno(fs, lfs_dino_getsize(fs, ip->i_din)) <= lbn) {
1066                     osize = lfs_blksize(fs, ip, lbn);
1067                     nsize = lfs_fragroundup(fs, offset + iosize);
1068                     if (lfs_lblktosize(fs, lbn) >= lfs_dino_getsize(fs, ip->i_din)) {
1069                               /* Brand new block or fragment */
1070                               frags = lfs_numfrags(fs, nsize);
1071                               if (bpp) {
1072                                         *bpp = bp = getblk(vp, lbn, nsize);
1073                                         bp->b_blkno = UNWRITTEN;
1074                               }
1075                               ip->i_lfs_effnblks += frags;
1076                               lfs_sb_subbfree(fs, frags);
1077                               lfs_dino_setdb(fs, ip->i_din, lbn, UNWRITTEN);
1078                     } else {
1079                               if (nsize <= osize) {
1080                                         /* No need to extend */
1081                                         if (bpp && (error = bread(vp, lbn, osize,
1082                                             0, &bp)))
1083                                                   return error;
1084                               } else {
1085                                         /* Extend existing block */
1086                                         if ((error =
1087                                              lfs_fragextend(vp, osize, nsize, lbn,
1088                                                                 (bpp ? &bp : NULL))))
1089                                                   return error;
1090                               }
1091                               if (bpp)
1092                                         *bpp = bp;
1093                     }
1094                     return 0;
1095           }
1096 
1097           error = ulfs_bmaparray(fs, vp, lbn, &daddr, &indirs[0], &num);
1098           if (error)
1099                     return (error);
1100 
1101           /*
1102            * Do byte accounting all at once, so we can gracefully fail *before*
1103            * we start assigning blocks.
1104            */
1105         frags = LFS_FSBTODB(fs, 1); /* frags = VFSTOULFS(vp->v_mount)->um_seqinc; */
1106           bcount = 0;
1107           if (daddr == UNASSIGNED) {
1108                     bcount = frags;
1109           }
1110           for (i = 1; i < num; ++i) {
1111                     if (!indirs[i].in_exists) {
1112                               bcount += frags;
1113                     }
1114           }
1115           lfs_sb_subbfree(fs, bcount);
1116           ip->i_lfs_effnblks += bcount;
1117 
1118           if (daddr == UNASSIGNED) {
1119                     if (num > 0 && lfs_dino_getib(fs, ip->i_din, indirs[0].in_off) == 0) {
1120                               lfs_dino_setib(fs, ip->i_din, indirs[0].in_off,
1121                                                UNWRITTEN);
1122                     }
1123 
1124                     /*
1125                      * Create new indirect blocks if necessary
1126                      */
1127                     if (num > 1) {
1128                               idaddr = lfs_dino_getib(fs, ip->i_din, indirs[0].in_off);
1129                               for (i = 1; i < num; ++i) {
1130                                         ibp = getblk(vp, indirs[i].in_lbn,
1131                                             lfs_sb_getbsize(fs));
1132                                         if (!indirs[i].in_exists) {
1133                                                   memset(ibp->b_data, 0, ibp->b_bufsize);
1134                                                   ibp->b_blkno = UNWRITTEN;
1135                                         } else if (!(ibp->b_flags & (B_DELWRI | B_DONE))) {
1136                                                   ibp->b_blkno = LFS_FSBTODB(fs, idaddr);
1137                                                   ibp->b_flags |= B_READ;
1138                                                   VOP_STRATEGY(ibp);
1139                                         }
1140                                         /*
1141                                          * This block exists, but the next one may not.
1142                                          * If that is the case mark it UNWRITTEN to
1143                                  * keep the accounting straight.
1144                                          */
1145                                         if (lfs_iblock_get(fs, ibp->b_data,
1146                                                             indirs[i].in_off) == 0)
1147                                                   lfs_iblock_set(fs, ibp->b_data,
1148                                                             indirs[i].in_off, UNWRITTEN);
1149                                         idaddr = lfs_iblock_get(fs, ibp->b_data,
1150                                                             indirs[i].in_off);
1151                                         if ((error = VOP_BWRITE(ibp)))
1152                                                   return error;
1153                               }
1154                     }
1155           }
1156 
1157 
1158           /*
1159            * Get the existing block from the cache, if requested.
1160            */
1161           if (bpp)
1162                     *bpp = bp = getblk(vp, lbn, lfs_blksize(fs, ip, lbn));
1163 
1164           /*
1165            * The block we are writing may be a brand new block
1166            * in which case we need to do accounting.
1167            *
1168            * We can tell a truly new block because ulfs_bmaparray will say
1169            * it is UNASSIGNED.  Once we allocate it we will assign it the
1170            * disk address UNWRITTEN.
1171            */
1172           if (daddr == UNASSIGNED) {
1173                     if (bpp) {
1174                               /* Note the new address */
1175                               bp->b_blkno = UNWRITTEN;
1176                     }
1177 
1178                     switch (num) {
1179                         case 0:
1180                               lfs_dino_setdb(fs, ip->i_din, lbn, UNWRITTEN);
1181                               break;
1182                         case 1:
1183                               lfs_dino_setib(fs, ip->i_din, indirs[0].in_off,
1184                                                UNWRITTEN);
1185                               break;
1186                         default:
1187                               idp = &indirs[num - 1];
1188                               if (bread(vp, idp->in_lbn, lfs_sb_getbsize(fs), 0, &ibp))
1189                                         panic("lfs_balloc: bread bno %lld",
1190                                             (long long)idp->in_lbn);
1191                               lfs_iblock_set(fs, ibp->b_data, idp->in_off,
1192                                                UNWRITTEN);
1193                               VOP_BWRITE(ibp);
1194                     }
1195           } else if (bpp && !(bp->b_flags & (B_DONE|B_DELWRI))) {
1196                     /*
1197                      * Not a brand new block, also not in the cache;
1198                      * read it in from disk.
1199                      */
1200                     if (iosize == lfs_sb_getbsize(fs))
1201                               /* Optimization: I/O is unnecessary. */
1202                               bp->b_blkno = daddr;
1203                     else {
1204                               /*
1205                                * We need to read the block to preserve the
1206                                * existing bytes.
1207                                */
1208                               bp->b_blkno = daddr;
1209                               bp->b_flags |= B_READ;
1210                               VOP_STRATEGY(bp);
1211                               return 0;
1212                     }
1213           }
1214 
1215           return (0);
1216 }
1217 
1218 int
lfs_fragextend(struct uvnode * vp,int osize,int nsize,daddr_t lbn,struct ubuf ** bpp)1219 lfs_fragextend(struct uvnode *vp, int osize, int nsize, daddr_t lbn,
1220                struct ubuf **bpp)
1221 {
1222           struct inode *ip;
1223           struct lfs *fs;
1224           int frags;
1225           int error;
1226 
1227           ip = VTOI(vp);
1228           fs = ip->i_lfs;
1229           frags = (long)lfs_numfrags(fs, nsize - osize);
1230           error = 0;
1231 
1232           /*
1233            * If we are not asked to actually return the block, all we need
1234            * to do is allocate space for it.  UBC will handle dirtying the
1235            * appropriate things and making sure it all goes to disk.
1236            * Don't bother to read in that case.
1237            */
1238           if (bpp && (error = bread(vp, lbn, osize, 0, bpp))) {
1239                     brelse(*bpp, 0);
1240                     goto out;
1241           }
1242 
1243           lfs_sb_subbfree(fs, frags);
1244           ip->i_lfs_effnblks += frags;
1245           ip->i_state |= IN_CHANGE | IN_UPDATE;
1246 
1247           if (bpp) {
1248                     (*bpp)->b_data = erealloc((*bpp)->b_data, nsize);
1249                     (void)memset((*bpp)->b_data + osize, 0, nsize - osize);
1250           }
1251 
1252     out:
1253           return (error);
1254 }
1255