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 1.10 2004/08/24 16:08:35 drhodus 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 "quota.h"
  47 #include "inode.h"
  48 #include "ufs_extern.h"
  49
  50 #include "fs.h"
  51 #include "ffs_extern.h"
  52
  53 /*
  54  * Balloc defines the structure of filesystem storage
  55  * by allocating the physical blocks on a device given
  56  * the inode and the logical block number in a file.
  57  *
  58  * ffs_balloc(struct vnode *a_vp, ufs_daddr_t a_lbn, int a_size,
  59  *            struct ucred *a_cred, int a_flags, struct buf *a_bpp)
  60  */
  61 int
  62 ffs_balloc(struct vop_balloc_args *ap)
  63 {
  64         struct inode *ip;
  65         ufs_daddr_t lbn;
  66         int size;
  67         struct ucred *cred;
  68         int flags;
  69         struct fs *fs;
  70         ufs_daddr_t nb;
  71         struct buf *bp, *nbp;
  72         struct vnode *vp;
  73         struct indir indirs[NIADDR + 2];
  74         ufs_daddr_t newb, *bap, pref;
  75         int deallocated, osize, nsize, num, i, error;
  76         ufs_daddr_t *allocib, *blkp, *allocblk, allociblk[NIADDR + 1];
  77         int unwindidx = -1;
  78         struct thread *td = curthread;  /* XXX */
  79
  80         vp = ap->a_vp;
  81         ip = VTOI(vp);
  82         fs = ip->i_fs;
  83         lbn = lblkno(fs, ap->a_startoffset);
  84         size = blkoff(fs, ap->a_startoffset) + ap->a_size;
  85         if (size > fs->fs_bsize)
  86                 panic("ffs_balloc: blk too big");
  87         *ap->a_bpp = NULL;
  88         if (lbn < 0)
  89                 return (EFBIG);
  90         cred = ap->a_cred;
  91         flags = ap->a_flags;
  92
  93         /*
  94          * If the next write will extend the file into a new block,
  95          * and the file is currently composed of a fragment
  96          * this fragment has to be extended to be a full block.
  97          */
  98         nb = lblkno(fs, ip->i_size);
  99         if (nb < NDADDR && nb < lbn) {
 100                 /*
 101                  * The filesize prior to this write can fit in direct
 102                  * blocks (ex. fragmentation is possibly done)
 103                  * we are now extending the file write beyond
 104                  * the block which has end of the file prior to this write.
 105                 osize = blksize(fs, ip, nb);
 106                 /*
 107                  * osize gives disk allocated size in the last block. It is
 108                  * either in fragments or a file system block size.
 109                  */
 110                 if (osize < fs->fs_bsize && osize > 0) {
 111                         /* A few fragments are already allocated, since the
 112                          * current extends beyond this block allocated the
 113                          * complete block as fragments are on in last block.
 114                          */
 115                         error = ffs_realloccg(ip, nb,
 116                                 ffs_blkpref(ip, nb, (int)nb, &ip->i_db[0]),
 117                                 osize, (int)fs->fs_bsize, cred, &bp);
 118                         if (error)
 119                                 return (error);
 120                         if (DOINGSOFTDEP(vp))
 121                                 softdep_setup_allocdirect(ip, nb,
 122                                     dbtofsb(fs, bp->b_blkno), ip->i_db[nb],
 123                                     fs->fs_bsize, osize, bp);
 124                         /* adjust the inode size, we just grew */
 125                         ip->i_size = smalllblktosize(fs, nb + 1);
 126                         ip->i_db[nb] = dbtofsb(fs, bp->b_blkno);
 127                         ip->i_flag |= IN_CHANGE | IN_UPDATE;
 128                         if (flags & B_SYNC)
 129                                 bwrite(bp);
 130                         else
 131                                 bawrite(bp);
 132                         /* bp is already released here */
 133                 }
 134         }
 135         /*
 136          * The first NDADDR blocks are direct blocks
 137          */
 138         if (lbn < NDADDR) {
 139                 nb = ip->i_db[lbn];
 140                 if (nb != 0 && ip->i_size >= smalllblktosize(fs, lbn + 1)) {
 141                         error = bread(vp, lbn, fs->fs_bsize, &bp);
 142                         if (error) {
 143                                 brelse(bp);
 144                                 return (error);
 145                         }
 146                         bp->b_blkno = fsbtodb(fs, nb);
 147                         *ap->a_bpp = bp;
 148                         return (0);
 149                 }
 150                 if (nb != 0) {
 151                         /*
 152                          * Consider need to reallocate a fragment.
 153                          */
 154                         osize = fragroundup(fs, blkoff(fs, ip->i_size));
 155                         nsize = fragroundup(fs, size);
 156                         if (nsize <= osize) {
 157                                 error = bread(vp, lbn, osize, &bp);
 158                                 if (error) {
 159                                         brelse(bp);
 160                                         return (error);
 161                                 }
 162                                 bp->b_blkno = fsbtodb(fs, nb);
 163                         } else {
 164                                 error = ffs_realloccg(ip, lbn,
 165                                     ffs_blkpref(ip, lbn, (int)lbn,
 166                                         &ip->i_db[0]), osize, nsize, cred, &bp);
 167                                 if (error)
 168                                         return (error);
 169                                 if (DOINGSOFTDEP(vp))
 170                                         softdep_setup_allocdirect(ip, lbn,
 171                                             dbtofsb(fs, bp->b_blkno), nb,
 172                                             nsize, osize, bp);
 173                         }
 174                 } else {
 175                         if (ip->i_size < smalllblktosize(fs, lbn + 1))
 176                                 nsize = fragroundup(fs, size);
 177                         else
 178                                 nsize = fs->fs_bsize;
 179                         error = ffs_alloc(ip, lbn,
 180                             ffs_blkpref(ip, lbn, (int)lbn, &ip->i_db[0]),
 181                             nsize, cred, &newb);
 182                         if (error)
 183                                 return (error);
 184                         bp = getblk(vp, lbn, nsize, 0, 0);
 185                         bp->b_blkno = fsbtodb(fs, newb);
 186                         if (flags & B_CLRBUF)
 187                                 vfs_bio_clrbuf(bp);
 188                         if (DOINGSOFTDEP(vp))
 189                                 softdep_setup_allocdirect(ip, lbn, newb, 0,
 190                                     nsize, 0, bp);
 191                 }
 192                 ip->i_db[lbn] = dbtofsb(fs, bp->b_blkno);
 193                 ip->i_flag |= IN_CHANGE | IN_UPDATE;
 194                 *ap->a_bpp = bp;
 195                 return (0);
 196         }
 197         /*
 198          * Determine the number of levels of indirection.
 199          */
 200         pref = 0;
 201         if ((error = ufs_getlbns(vp, lbn, indirs, &num)) != 0)
 202                 return(error);
 203 #ifdef DIAGNOSTIC
 204         if (num < 1)
 205                 panic ("ffs_balloc: ufs_bmaparray returned indirect block");
 206 #endif
 207         /*
 208          * Fetch the first indirect block allocating if necessary.
 209          */
 210         --num;
 211         nb = ip->i_ib[indirs[0].in_off];
 212         allocib = NULL;
 213         allocblk = allociblk;
 214         if (nb == 0) {
 215                 pref = ffs_blkpref(ip, lbn, 0, (ufs_daddr_t *)0);
 216                 if ((error = ffs_alloc(ip, lbn, pref, (int)fs->fs_bsize,
 217                     cred, &newb)) != 0)
 218                         return (error);
 219                 nb = newb;
 220                 *allocblk++ = nb;
 221                 bp = getblk(vp, indirs[1].in_lbn, fs->fs_bsize, 0, 0);
 222                 bp->b_blkno = fsbtodb(fs, nb);
 223                 vfs_bio_clrbuf(bp);
 224                 if (DOINGSOFTDEP(vp)) {
 225                         softdep_setup_allocdirect(ip, NDADDR + indirs[0].in_off,
 226                             newb, 0, fs->fs_bsize, 0, bp);
 227                         bdwrite(bp);
 228                 } else {
 229                         /*
 230                          * Write synchronously so that indirect blocks
 231                          * never point at garbage.
 232                          */
 233                         if (DOINGASYNC(vp))
 234                                 bdwrite(bp);
 235                         else if ((error = bwrite(bp)) != 0)
 236                                 goto fail;
 237                 }
 238                 allocib = &ip->i_ib[indirs[0].in_off];
 239                 *allocib = nb;
 240                 ip->i_flag |= IN_CHANGE | IN_UPDATE;
 241         }
 242         /*
 243          * Fetch through the indirect blocks, allocating as necessary.
 244          */
 245         for (i = 1;;) {
 246                 error = bread(vp, indirs[i].in_lbn, (int)fs->fs_bsize, &bp);
 247                 if (error) {
 248                         brelse(bp);
 249                         goto fail;
 250                 }
 251                 bap = (ufs_daddr_t *)bp->b_data;
 252                 nb = bap[indirs[i].in_off];
 253                 if (i == num)
 254                         break;
 255                 i += 1;
 256                 if (nb != 0) {
 257                         bqrelse(bp);
 258                         continue;
 259                 }
 260                 if (pref == 0)
 261                         pref = ffs_blkpref(ip, lbn, 0, (ufs_daddr_t *)0);
 262                 if ((error =
 263                     ffs_alloc(ip, lbn, pref, (int)fs->fs_bsize, cred, &newb)) != 0) {
 264                         brelse(bp);
 265                         goto fail;
 266                 }
 267                 nb = newb;
 268                 *allocblk++ = nb;
 269                 nbp = getblk(vp, indirs[i].in_lbn, fs->fs_bsize, 0, 0);
 270                 nbp->b_blkno = fsbtodb(fs, nb);
 271                 vfs_bio_clrbuf(nbp);
 272                 if (DOINGSOFTDEP(vp)) {
 273                         softdep_setup_allocindir_meta(nbp, ip, bp,
 274                             indirs[i - 1].in_off, nb);
 275                         bdwrite(nbp);
 276                 } else {
 277                         /*
 278                          * Write synchronously so that indirect blocks
 279                          * never point at garbage.
 280                          */
 281                         if ((error = bwrite(nbp)) != 0) {
 282                                 brelse(bp);
 283                                 goto fail;
 284                         }
 285                 }
 286                 bap[indirs[i - 1].in_off] = nb;
 287                 if (allocib == NULL && unwindidx < 0)
 288                         unwindidx = i - 1;
 289                 /*
 290                  * If required, write synchronously, otherwise use
 291                  * delayed write.
 292                  */
 293                 if (flags & B_SYNC) {
 294                         bwrite(bp);
 295                 } else {
 296                         if (bp->b_bufsize == fs->fs_bsize)
 297                                 bp->b_flags |= B_CLUSTEROK;
 298                         bdwrite(bp);
 299                 }
 300         }
 301         /*
 302          * Get the data block, allocating if necessary.
 303          */
 304         if (nb == 0) {
 305                 pref = ffs_blkpref(ip, lbn, indirs[i].in_off, &bap[0]);
 306                 error = ffs_alloc(ip,
 307                     lbn, pref, (int)fs->fs_bsize, cred, &newb);
 308                 if (error) {
 309                         brelse(bp);
 310                         goto fail;
 311                 }
 312                 nb = newb;
 313                 *allocblk++ = nb;
 314                 nbp = getblk(vp, lbn, fs->fs_bsize, 0, 0);
 315                 nbp->b_blkno = fsbtodb(fs, nb);
 316                 if (flags & B_CLRBUF)
 317                         vfs_bio_clrbuf(nbp);
 318                 if (DOINGSOFTDEP(vp))
 319                         softdep_setup_allocindir_page(ip, lbn, bp,
 320                             indirs[i].in_off, nb, 0, nbp);
 321                 bap[indirs[i].in_off] = nb;
 322                 /*
 323                  * If required, write synchronously, otherwise use
 324                  * delayed write.
 325                  */
 326                 if (flags & B_SYNC) {
 327                         bwrite(bp);
 328                 } else {
 329                         if (bp->b_bufsize == fs->fs_bsize)
 330                                 bp->b_flags |= B_CLUSTEROK;
 331                         bdwrite(bp);
 332                 }
 333                 *ap->a_bpp = nbp;
 334                 return (0);
 335         }
 336         brelse(bp);
 337         /*
 338          * If requested clear invalid portions of the buffer.  If we
 339          * have to do a read-before-write (typical if B_CLRBUF is set),
 340          * try to do some read-ahead in the sequential case to reduce
 341          * the number of I/O transactions.
 342          */
 343         if (flags & B_CLRBUF) {
 344                 int seqcount = (flags & B_SEQMASK) >> B_SEQSHIFT;
 345                 if (seqcount &&
 346                     (vp->v_mount->mnt_flag & MNT_NOCLUSTERR) == 0) {
 347                         error = cluster_read(vp, ip->i_size, lbn,
 348                                     (int)fs->fs_bsize,
 349                                     MAXBSIZE, seqcount, &nbp);
 350                 } else {
 351                         error = bread(vp, lbn, (int)fs->fs_bsize, &nbp);
 352                 }
 353                 if (error) {
 354                         brelse(nbp);
 355                         goto fail;
 356                 }
 357         } else {
 358                 nbp = getblk(vp, lbn, fs->fs_bsize, 0, 0);
 359                 nbp->b_blkno = fsbtodb(fs, nb);
 360         }
 361         *ap->a_bpp = nbp;
 362         return (0);
 363 fail:
 364         /*
 365          * If we have failed part way through block allocation, we
 366          * have to deallocate any indirect blocks that we have allocated.
 367          * We have to fsync the file before we start to get rid of all
 368          * of its dependencies so that we do not leave them dangling.
 369          * We have to sync it at the end so that the soft updates code
 370          * does not find any untracked changes. Although this is really
 371          * slow, running out of disk space is not expected to be a common
 372          * occurence. The error return from fsync is ignored as we already
 373          * have an error to return to the user.
 374          */
 375         (void) VOP_FSYNC(vp, MNT_WAIT, td);
 376         for (deallocated = 0, blkp = allociblk; blkp < allocblk; blkp++) {
 377                 ffs_blkfree(ip, *blkp, fs->fs_bsize);
 378                 deallocated += fs->fs_bsize;
 379         }
 380         if (allocib != NULL) {
 381                 *allocib = 0;
 382         } else if (unwindidx >= 0) {
 383                 int r;
 384
 385                 r = bread(vp, indirs[unwindidx].in_lbn, (int)fs->fs_bsize, &bp);
 386                 if (r) {
 387                         panic("Could not unwind indirect block, error %d", r);
 388                         brelse(bp);
 389                 } else {
 390                         bap = (ufs_daddr_t *)bp->b_data;
 391                         bap[indirs[unwindidx].in_off] = 0;
 392                         if (flags & B_SYNC) {
 393                                 bwrite(bp);
 394                         } else {
 395                                 if (bp->b_bufsize == fs->fs_bsize)
 396                                         bp->b_flags |= B_CLUSTEROK;
 397                                 bdwrite(bp);
 398                         }
 399                 }
 400         }
 401         if (deallocated) {
 402 #ifdef QUOTA
 403                 /*
 404                  * Restore user's disk quota because allocation failed.
 405                  */
 406                 (void) chkdq(ip, (long)-btodb(deallocated), cred, FORCE);
 407 #endif
 408                 ip->i_blocks -= btodb(deallocated);
 409                 ip->i_flag |= IN_CHANGE | IN_UPDATE;
 410         }
 411         (void) VOP_FSYNC(vp, MNT_WAIT, td);
 412         return (error);
 413 }