sys/vfs/ufs/ffs_balloc.c

   1 /*
   2  * Copyright (c) 1982, 1986, 1989, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *      This product includes software developed by the University of
  16  *      California, Berkeley and its contributors.
  17  * 4. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  *
  33  *      @(#)ffs_balloc.c        8.8 (Berkeley) 6/16/95
  34  * $FreeBSD: src/sys/ufs/ffs/ffs_balloc.c,v 1.26.2.1 2002/10/10 19:48:20 dillon Exp $
  35  * $DragonFly: src/sys/vfs/ufs/ffs_balloc.c,v 1.5 2003/06/26 05:55:20 dillon Exp $
  36  */
  37
  38 #include <sys/param.h>
  39 #include <sys/systm.h>
  40 #include <sys/proc.h>
  41 #include <sys/buf.h>
  42 #include <sys/lock.h>
  43 #include <sys/mount.h>
  44 #include <sys/vnode.h>
  45
  46 #include <ufs/ufs/quota.h>
  47 #include <ufs/ufs/inode.h>
  48 #include <ufs/ufs/ufs_extern.h>
  49
  50 #include <ufs/ffs/fs.h>
  51 #include <ufs/ffs/ffs_extern.h>
  52
  53 /*
  54  * Balloc defines the structure of file system storage
  55  * by allocating the physical blocks on a device given
  56  * the inode and the logical block number in a file.
  57  */
  58 int
  59 ffs_balloc(ap)
  60         struct vop_balloc_args /* {
  61                 struct vnode *a_vp;
  62                 ufs_daddr_t a_lbn;
  63                 int a_size;
  64                 struct ucred *a_cred;
  65                 int a_flags;
  66                 struct buf *a_bpp;
  67         } */ *ap;
  68 {
  69         struct inode *ip;
  70         ufs_daddr_t lbn;
  71         int size;
  72         struct ucred *cred;
  73         int flags;
  74         struct fs *fs;
  75         ufs_daddr_t nb;
  76         struct buf *bp, *nbp;
  77         struct vnode *vp;
  78         struct indir indirs[NIADDR + 2];
  79         ufs_daddr_t newb, *bap, pref;
  80         int deallocated, osize, nsize, num, i, error;
  81         ufs_daddr_t *allocib, *blkp, *allocblk, allociblk[NIADDR + 1];
  82         int unwindidx = -1;
  83         struct thread *td = curthread;  /* XXX */
  84
  85         vp = ap->a_vp;
  86         ip = VTOI(vp);
  87         fs = ip->i_fs;
  88         lbn = lblkno(fs, ap->a_startoffset);
  89         size = blkoff(fs, ap->a_startoffset) + ap->a_size;
  90         if (size > fs->fs_bsize)
  91                 panic("ffs_balloc: blk too big");
  92         *ap->a_bpp = NULL;
  93         if (lbn < 0)
  94                 return (EFBIG);
  95         cred = ap->a_cred;
  96         flags = ap->a_flags;
  97
  98         /*
  99          * If the next write will extend the file into a new block,
 100          * and the file is currently composed of a fragment
 101          * this fragment has to be extended to be a full block.
 102          */
 103         nb = lblkno(fs, ip->i_size);
 104         if (nb < NDADDR && nb < lbn) {
 105                 osize = blksize(fs, ip, nb);
 106                 if (osize < fs->fs_bsize && osize > 0) {
 107                         error = ffs_realloccg(ip, nb,
 108                                 ffs_blkpref(ip, nb, (int)nb, &ip->i_db[0]),
 109                                 osize, (int)fs->fs_bsize, cred, &bp);
 110                         if (error)
 111                                 return (error);
 112                         if (DOINGSOFTDEP(vp))
 113                                 softdep_setup_allocdirect(ip, nb,
 114                                     dbtofsb(fs, bp->b_blkno), ip->i_db[nb],
 115                                     fs->fs_bsize, osize, bp);
 116                         ip->i_size = smalllblktosize(fs, nb + 1);
 117                         ip->i_db[nb] = dbtofsb(fs, bp->b_blkno);
 118                         ip->i_flag |= IN_CHANGE | IN_UPDATE;
 119                         if (flags & B_SYNC)
 120                                 bwrite(bp);
 121                         else
 122                                 bawrite(bp);
 123                 }
 124         }
 125         /*
 126          * The first NDADDR blocks are direct blocks
 127          */
 128         if (lbn < NDADDR) {
 129                 nb = ip->i_db[lbn];
 130                 if (nb != 0 && ip->i_size >= smalllblktosize(fs, lbn + 1)) {
 131                         error = bread(vp, lbn, fs->fs_bsize, &bp);
 132                         if (error) {
 133                                 brelse(bp);
 134                                 return (error);
 135                         }
 136                         bp->b_blkno = fsbtodb(fs, nb);
 137                         *ap->a_bpp = bp;
 138                         return (0);
 139                 }
 140                 if (nb != 0) {
 141                         /*
 142                          * Consider need to reallocate a fragment.
 143                          */
 144                         osize = fragroundup(fs, blkoff(fs, ip->i_size));
 145                         nsize = fragroundup(fs, size);
 146                         if (nsize <= osize) {
 147                                 error = bread(vp, lbn, osize, &bp);
 148                                 if (error) {
 149                                         brelse(bp);
 150                                         return (error);
 151                                 }
 152                                 bp->b_blkno = fsbtodb(fs, nb);
 153                         } else {
 154                                 error = ffs_realloccg(ip, lbn,
 155                                     ffs_blkpref(ip, lbn, (int)lbn,
 156                                         &ip->i_db[0]), osize, nsize, cred, &bp);
 157                                 if (error)
 158                                         return (error);
 159                                 if (DOINGSOFTDEP(vp))
 160                                         softdep_setup_allocdirect(ip, lbn,
 161                                             dbtofsb(fs, bp->b_blkno), nb,
 162                                             nsize, osize, bp);
 163                         }
 164                 } else {
 165                         if (ip->i_size < smalllblktosize(fs, lbn + 1))
 166                                 nsize = fragroundup(fs, size);
 167                         else
 168                                 nsize = fs->fs_bsize;
 169                         error = ffs_alloc(ip, lbn,
 170                             ffs_blkpref(ip, lbn, (int)lbn, &ip->i_db[0]),
 171                             nsize, cred, &newb);
 172                         if (error)
 173                                 return (error);
 174                         bp = getblk(vp, lbn, nsize, 0, 0);
 175                         bp->b_blkno = fsbtodb(fs, newb);
 176                         if (flags & B_CLRBUF)
 177                                 vfs_bio_clrbuf(bp);
 178                         if (DOINGSOFTDEP(vp))
 179                                 softdep_setup_allocdirect(ip, lbn, newb, 0,
 180                                     nsize, 0, bp);
 181                 }
 182                 ip->i_db[lbn] = dbtofsb(fs, bp->b_blkno);
 183                 ip->i_flag |= IN_CHANGE | IN_UPDATE;
 184                 *ap->a_bpp = bp;
 185                 return (0);
 186         }
 187         /*
 188          * Determine the number of levels of indirection.
 189          */
 190         pref = 0;
 191         if ((error = ufs_getlbns(vp, lbn, indirs, &num)) != 0)
 192                 return(error);
 193 #ifdef DIAGNOSTIC
 194         if (num < 1)
 195                 panic ("ffs_balloc: ufs_bmaparray returned indirect block");
 196 #endif
 197         /*
 198          * Fetch the first indirect block allocating if necessary.
 199          */
 200         --num;
 201         nb = ip->i_ib[indirs[0].in_off];
 202         allocib = NULL;
 203         allocblk = allociblk;
 204         if (nb == 0) {
 205                 pref = ffs_blkpref(ip, lbn, 0, (ufs_daddr_t *)0);
 206                 if ((error = ffs_alloc(ip, lbn, pref, (int)fs->fs_bsize,
 207                     cred, &newb)) != 0)
 208                         return (error);
 209                 nb = newb;
 210                 *allocblk++ = nb;
 211                 bp = getblk(vp, indirs[1].in_lbn, fs->fs_bsize, 0, 0);
 212                 bp->b_blkno = fsbtodb(fs, nb);
 213                 vfs_bio_clrbuf(bp);
 214                 if (DOINGSOFTDEP(vp)) {
 215                         softdep_setup_allocdirect(ip, NDADDR + indirs[0].in_off,
 216                             newb, 0, fs->fs_bsize, 0, bp);
 217                         bdwrite(bp);
 218                 } else {
 219                         /*
 220                          * Write synchronously so that indirect blocks
 221                          * never point at garbage.
 222                          */
 223                         if (DOINGASYNC(vp))
 224                                 bdwrite(bp);
 225                         else if ((error = bwrite(bp)) != 0)
 226                                 goto fail;
 227                 }
 228                 allocib = &ip->i_ib[indirs[0].in_off];
 229                 *allocib = nb;
 230                 ip->i_flag |= IN_CHANGE | IN_UPDATE;
 231         }
 232         /*
 233          * Fetch through the indirect blocks, allocating as necessary.
 234          */
 235         for (i = 1;;) {
 236                 error = bread(vp, indirs[i].in_lbn, (int)fs->fs_bsize, &bp);
 237                 if (error) {
 238                         brelse(bp);
 239                         goto fail;
 240                 }
 241                 bap = (ufs_daddr_t *)bp->b_data;
 242                 nb = bap[indirs[i].in_off];
 243                 if (i == num)
 244                         break;
 245                 i += 1;
 246                 if (nb != 0) {
 247                         bqrelse(bp);
 248                         continue;
 249                 }
 250                 if (pref == 0)
 251                         pref = ffs_blkpref(ip, lbn, 0, (ufs_daddr_t *)0);
 252                 if ((error =
 253                     ffs_alloc(ip, lbn, pref, (int)fs->fs_bsize, cred, &newb)) != 0) {
 254                         brelse(bp);
 255                         goto fail;
 256                 }
 257                 nb = newb;
 258                 *allocblk++ = nb;
 259                 nbp = getblk(vp, indirs[i].in_lbn, fs->fs_bsize, 0, 0);
 260                 nbp->b_blkno = fsbtodb(fs, nb);
 261                 vfs_bio_clrbuf(nbp);
 262                 if (DOINGSOFTDEP(vp)) {
 263                         softdep_setup_allocindir_meta(nbp, ip, bp,
 264                             indirs[i - 1].in_off, nb);
 265                         bdwrite(nbp);
 266                 } else {
 267                         /*
 268                          * Write synchronously so that indirect blocks
 269                          * never point at garbage.
 270                          */
 271                         if ((error = bwrite(nbp)) != 0) {
 272                                 brelse(bp);
 273                                 goto fail;
 274                         }
 275                 }
 276                 bap[indirs[i - 1].in_off] = nb;
 277                 if (allocib == NULL && unwindidx < 0)
 278                         unwindidx = i - 1;
 279                 /*
 280                  * If required, write synchronously, otherwise use
 281                  * delayed write.
 282                  */
 283                 if (flags & B_SYNC) {
 284                         bwrite(bp);
 285                 } else {
 286                         if (bp->b_bufsize == fs->fs_bsize)
 287                                 bp->b_flags |= B_CLUSTEROK;
 288                         bdwrite(bp);
 289                 }
 290         }
 291         /*
 292          * Get the data block, allocating if necessary.
 293          */
 294         if (nb == 0) {
 295                 pref = ffs_blkpref(ip, lbn, indirs[i].in_off, &bap[0]);
 296                 error = ffs_alloc(ip,
 297                     lbn, pref, (int)fs->fs_bsize, cred, &newb);
 298                 if (error) {
 299                         brelse(bp);
 300                         goto fail;
 301                 }
 302                 nb = newb;
 303                 *allocblk++ = nb;
 304                 nbp = getblk(vp, lbn, fs->fs_bsize, 0, 0);
 305                 nbp->b_blkno = fsbtodb(fs, nb);
 306                 if (flags & B_CLRBUF)
 307                         vfs_bio_clrbuf(nbp);
 308                 if (DOINGSOFTDEP(vp))
 309                         softdep_setup_allocindir_page(ip, lbn, bp,
 310                             indirs[i].in_off, nb, 0, nbp);
 311                 bap[indirs[i].in_off] = nb;
 312                 /*
 313                  * If required, write synchronously, otherwise use
 314                  * delayed write.
 315                  */
 316                 if (flags & B_SYNC) {
 317                         bwrite(bp);
 318                 } else {
 319                         if (bp->b_bufsize == fs->fs_bsize)
 320                                 bp->b_flags |= B_CLUSTEROK;
 321                         bdwrite(bp);
 322                 }
 323                 *ap->a_bpp = nbp;
 324                 return (0);
 325         }
 326         brelse(bp);
 327         /*
 328          * If requested clear invalid portions of the buffer.  If we
 329          * have to do a read-before-write (typical if B_CLRBUF is set),
 330          * try to do some read-ahead in the sequential case to reduce
 331          * the number of I/O transactions.
 332          */
 333         if (flags & B_CLRBUF) {
 334                 int seqcount = (flags & B_SEQMASK) >> B_SEQSHIFT;
 335                 if (seqcount &&
 336                     (vp->v_mount->mnt_flag & MNT_NOCLUSTERR) == 0) {
 337                         error = cluster_read(vp, ip->i_size, lbn,
 338                                     (int)fs->fs_bsize,
 339                                     MAXBSIZE, seqcount, &nbp);
 340                 } else {
 341                         error = bread(vp, lbn, (int)fs->fs_bsize, &nbp);
 342                 }
 343                 if (error) {
 344                         brelse(nbp);
 345                         goto fail;
 346                 }
 347         } else {
 348                 nbp = getblk(vp, lbn, fs->fs_bsize, 0, 0);
 349                 nbp->b_blkno = fsbtodb(fs, nb);
 350         }
 351         *ap->a_bpp = nbp;
 352         return (0);
 353 fail:
 354         /*
 355          * If we have failed part way through block allocation, we
 356          * have to deallocate any indirect blocks that we have allocated.
 357          * We have to fsync the file before we start to get rid of all
 358          * of its dependencies so that we do not leave them dangling.
 359          * We have to sync it at the end so that the soft updates code
 360          * does not find any untracked changes. Although this is really
 361          * slow, running out of disk space is not expected to be a common
 362          * occurence. The error return from fsync is ignored as we already
 363          * have an error to return to the user.
 364          */
 365         (void) VOP_FSYNC(vp, MNT_WAIT, td);
 366         for (deallocated = 0, blkp = allociblk; blkp < allocblk; blkp++) {
 367                 ffs_blkfree(ip, *blkp, fs->fs_bsize);
 368                 deallocated += fs->fs_bsize;
 369         }
 370         if (allocib != NULL) {
 371                 *allocib = 0;
 372         } else if (unwindidx >= 0) {
 373                 int r;
 374
 375                 r = bread(vp, indirs[unwindidx].in_lbn, (int)fs->fs_bsize, &bp);
 376                 if (r) {
 377                         panic("Could not unwind indirect block, error %d", r);
 378                         brelse(bp);
 379                 } else {
 380                         bap = (ufs_daddr_t *)bp->b_data;
 381                         bap[indirs[unwindidx].in_off] = 0;
 382                         if (flags & B_SYNC) {
 383                                 bwrite(bp);
 384                         } else {
 385                                 if (bp->b_bufsize == fs->fs_bsize)
 386                                         bp->b_flags |= B_CLUSTEROK;
 387                                 bdwrite(bp);
 388                         }
 389                 }
 390         }
 391         if (deallocated) {
 392 #ifdef QUOTA
 393                 /*
 394                  * Restore user's disk quota because allocation failed.
 395                  */
 396                 (void) chkdq(ip, (long)-btodb(deallocated), cred, FORCE);
 397 #endif
 398                 ip->i_blocks -= btodb(deallocated);
 399                 ip->i_flag |= IN_CHANGE | IN_UPDATE;
 400         }
 401         (void) VOP_FSYNC(vp, MNT_WAIT, td);
 402         return (error);
 403 }