fs/jfs/jfs_mount.c

   1 /*
   2  *   Copyright (C) International Business Machines Corp., 2000-2004
   3  *
   4  *   This program is free software;  you can redistribute it and/or modify
   5  *   it under the terms of the GNU General Public License as published by
   6  *   the Free Software Foundation; either version 2 of the License, or
   7  *   (at your option) any later version.
   8  *
   9  *   This program is distributed in the hope that it will be useful,
  10  *   but WITHOUT ANY WARRANTY;  without even the implied warranty of
  11  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
  12  *   the GNU General Public License for more details.
  13  *
  14  *   You should have received a copy of the GNU General Public License
  15  *   along with this program;  if not, write to the Free Software
  16  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  17  */
  18
  19 /*
  20  * Module: jfs_mount.c
  21  *
  22  * note: file system in transition to aggregate/fileset:
  23  *
  24  * file system mount is interpreted as the mount of aggregate,
  25  * if not already mounted, and mount of the single/only fileset in
  26  * the aggregate;
  27  *
  28  * a file system/aggregate is represented by an internal inode
  29  * (aka mount inode) initialized with aggregate superblock;
  30  * each vfs represents a fileset, and points to its "fileset inode
  31  * allocation map inode" (aka fileset inode):
  32  * (an aggregate itself is structured recursively as a filset:
  33  * an internal vfs is constructed and points to its "fileset inode
  34  * allocation map inode" (aka aggregate inode) where each inode
  35  * represents a fileset inode) so that inode number is mapped to
  36  * on-disk inode in uniform way at both aggregate and fileset level;
  37  *
  38  * each vnode/inode of a fileset is linked to its vfs (to facilitate
  39  * per fileset inode operations, e.g., unmount of a fileset, etc.);
  40  * each inode points to the mount inode (to facilitate access to
  41  * per aggregate information, e.g., block size, etc.) as well as
  42  * its file set inode.
  43  *
  44  *   aggregate
  45  *   ipmnt
  46  *   mntvfs -> fileset ipimap+ -> aggregate ipbmap -> aggregate ipaimap;
  47  *             fileset vfs     -> vp(1) <-> ... <-> vp(n) <->vproot;
  48  */
  49
  50 #include <linux/fs.h>
  51 #include <linux/buffer_head.h>
  52
  53 #include "jfs_incore.h"
  54 #include "jfs_filsys.h"
  55 #include "jfs_superblock.h"
  56 #include "jfs_dmap.h"
  57 #include "jfs_imap.h"
  58 #include "jfs_metapage.h"
  59 #include "jfs_debug.h"
  60
  61
  62 /*
  63  * forward references
  64  */
  65 static int chkSuper(struct super_block *);
  66 static int logMOUNT(struct super_block *sb);
  67
  68 /*
  69  * NAME:        jfs_mount(sb)
  70  *
  71  * FUNCTION:    vfs_mount()
  72  *
  73  * PARAMETER:   sb      - super block
  74  *
  75  * RETURN:      -EBUSY  - device already mounted or open for write
  76  *              -EBUSY  - cvrdvp already mounted;
  77  *              -EBUSY  - mount table full
  78  *              -ENOTDIR- cvrdvp not directory on a device mount
  79  *              -ENXIO  - device open failure
  80  */
  81 int jfs_mount(struct super_block *sb)
  82 {
  83         int rc = 0;             /* Return code */
  84         struct jfs_sb_info *sbi = JFS_SBI(sb);
  85         struct inode *ipaimap = NULL;
  86         struct inode *ipaimap2 = NULL;
  87         struct inode *ipimap = NULL;
  88         struct inode *ipbmap = NULL;
  89
  90         /*
  91          * read/validate superblock
  92          * (initialize mount inode from the superblock)
  93          */
  94         if ((rc = chkSuper(sb))) {
  95                 goto errout20;
  96         }
  97
  98         ipaimap = diReadSpecial(sb, AGGREGATE_I, 0);
  99         if (ipaimap == NULL) {
 100                 jfs_err("jfs_mount: Failed to read AGGREGATE_I");
 101                 rc = -EIO;
 102                 goto errout20;
 103         }
 104         sbi->ipaimap = ipaimap;
 105
 106         jfs_info("jfs_mount: ipaimap:0x%p", ipaimap);
 107
 108         /*
 109          * initialize aggregate inode allocation map
 110          */
 111         if ((rc = diMount(ipaimap))) {
 112                 jfs_err("jfs_mount: diMount(ipaimap) failed w/rc = %d", rc);
 113                 goto errout21;
 114         }
 115
 116         /*
 117          * open aggregate block allocation map
 118          */
 119         ipbmap = diReadSpecial(sb, BMAP_I, 0);
 120         if (ipbmap == NULL) {
 121                 rc = -EIO;
 122                 goto errout22;
 123         }
 124
 125         jfs_info("jfs_mount: ipbmap:0x%p", ipbmap);
 126
 127         sbi->ipbmap = ipbmap;
 128
 129         /*
 130          * initialize aggregate block allocation map
 131          */
 132         if ((rc = dbMount(ipbmap))) {
 133                 jfs_err("jfs_mount: dbMount failed w/rc = %d", rc);
 134                 goto errout22;
 135         }
 136
 137         /*
 138          * open the secondary aggregate inode allocation map
 139          *
 140          * This is a duplicate of the aggregate inode allocation map.
 141          *
 142          * hand craft a vfs in the same fashion as we did to read ipaimap.
 143          * By adding INOSPEREXT (32) to the inode number, we are telling
 144          * diReadSpecial that we are reading from the secondary aggregate
 145          * inode table.  This also creates a unique entry in the inode hash
 146          * table.
 147          */
 148         if ((sbi->mntflag & JFS_BAD_SAIT) == 0) {
 149                 ipaimap2 = diReadSpecial(sb, AGGREGATE_I, 1);
 150                 if (!ipaimap2) {
 151                         jfs_err("jfs_mount: Failed to read AGGREGATE_I");
 152                         rc = -EIO;
 153                         goto errout35;
 154                 }
 155                 sbi->ipaimap2 = ipaimap2;
 156
 157                 jfs_info("jfs_mount: ipaimap2:0x%p", ipaimap2);
 158
 159                 /*
 160                  * initialize secondary aggregate inode allocation map
 161                  */
 162                 if ((rc = diMount(ipaimap2))) {
 163                         jfs_err("jfs_mount: diMount(ipaimap2) failed, rc = %d",
 164                                 rc);
 165                         goto errout35;
 166                 }
 167         } else
 168                 /* Secondary aggregate inode table is not valid */
 169                 sbi->ipaimap2 = NULL;
 170
 171         /*
 172          *      mount (the only/single) fileset
 173          */
 174         /*
 175          * open fileset inode allocation map (aka fileset inode)
 176          */
 177         ipimap = diReadSpecial(sb, FILESYSTEM_I, 0);
 178         if (ipimap == NULL) {
 179                 jfs_err("jfs_mount: Failed to read FILESYSTEM_I");
 180                 /* open fileset secondary inode allocation map */
 181                 rc = -EIO;
 182                 goto errout40;
 183         }
 184         jfs_info("jfs_mount: ipimap:0x%p", ipimap);
 185
 186         /* map further access of per fileset inodes by the fileset inode */
 187         sbi->ipimap = ipimap;
 188
 189         /* initialize fileset inode allocation map */
 190         if ((rc = diMount(ipimap))) {
 191                 jfs_err("jfs_mount: diMount failed w/rc = %d", rc);
 192                 goto errout41;
 193         }
 194
 195         goto out;
 196
 197         /*
 198          *      unwind on error
 199          */
 200       errout41:         /* close fileset inode allocation map inode */
 201         diFreeSpecial(ipimap);
 202
 203       errout40:         /* fileset closed */
 204
 205         /* close secondary aggregate inode allocation map */
 206         if (ipaimap2) {
 207                 diUnmount(ipaimap2, 1);
 208                 diFreeSpecial(ipaimap2);
 209         }
 210
 211       errout35:
 212
 213         /* close aggregate block allocation map */
 214         dbUnmount(ipbmap, 1);
 215         diFreeSpecial(ipbmap);
 216
 217       errout22:         /* close aggregate inode allocation map */
 218
 219         diUnmount(ipaimap, 1);
 220
 221       errout21:         /* close aggregate inodes */
 222         diFreeSpecial(ipaimap);
 223       errout20:         /* aggregate closed */
 224
 225       out:
 226
 227         if (rc)
 228                 jfs_err("Mount JFS Failure: %d", rc);
 229
 230         return rc;
 231 }
 232
 233 /*
 234  * NAME:        jfs_mount_rw(sb, remount)
 235  *
 236  * FUNCTION:    Completes read-write mount, or remounts read-only volume
 237  *              as read-write
 238  */
 239 int jfs_mount_rw(struct super_block *sb, int remount)
 240 {
 241         struct jfs_sb_info *sbi = JFS_SBI(sb);
 242         int rc;
 243
 244         /*
 245          * If we are re-mounting a previously read-only volume, we want to
 246          * re-read the inode and block maps, since fsck.jfs may have updated
 247          * them.
 248          */
 249         if (remount) {
 250                 if (chkSuper(sb) || (sbi->state != FM_CLEAN))
 251                         return -EINVAL;
 252
 253                 truncate_inode_pages(sbi->ipimap->i_mapping, 0);
 254                 truncate_inode_pages(sbi->ipbmap->i_mapping, 0);
 255                 diUnmount(sbi->ipimap, 1);
 256                 if ((rc = diMount(sbi->ipimap))) {
 257                         jfs_err("jfs_mount_rw: diMount failed!");
 258                         return rc;
 259                 }
 260
 261                 dbUnmount(sbi->ipbmap, 1);
 262                 if ((rc = dbMount(sbi->ipbmap))) {
 263                         jfs_err("jfs_mount_rw: dbMount failed!");
 264                         return rc;
 265                 }
 266         }
 267
 268         /*
 269          * open/initialize log
 270          */
 271         if ((rc = lmLogOpen(sb)))
 272                 return rc;
 273
 274         /*
 275          * update file system superblock;
 276          */
 277         if ((rc = updateSuper(sb, FM_MOUNT))) {
 278                 jfs_err("jfs_mount: updateSuper failed w/rc = %d", rc);
 279                 lmLogClose(sb);
 280                 return rc;
 281         }
 282
 283         /*
 284          * write MOUNT log record of the file system
 285          */
 286         logMOUNT(sb);
 287
 288         return rc;
 289 }
 290
 291 /*
 292  *      chkSuper()
 293  *
 294  * validate the superblock of the file system to be mounted and
 295  * get the file system parameters.
 296  *
 297  * returns
 298  *      0 with fragsize set if check successful
 299  *      error code if not successful
 300  */
 301 static int chkSuper(struct super_block *sb)
 302 {
 303         int rc = 0;
 304         struct jfs_sb_info *sbi = JFS_SBI(sb);
 305         struct jfs_superblock *j_sb;
 306         struct buffer_head *bh;
 307         int AIM_bytesize, AIT_bytesize;
 308         int expected_AIM_bytesize, expected_AIT_bytesize;
 309         s64 AIM_byte_addr, AIT_byte_addr, fsckwsp_addr;
 310         s64 byte_addr_diff0, byte_addr_diff1;
 311         s32 bsize;
 312
 313         if ((rc = readSuper(sb, &bh)))
 314                 return rc;
 315         j_sb = (struct jfs_superblock *)bh->b_data;
 316
 317         /*
 318          * validate superblock
 319          */
 320         /* validate fs signature */
 321         if (strncmp(j_sb->s_magic, JFS_MAGIC, 4) ||
 322             le32_to_cpu(j_sb->s_version) > JFS_VERSION) {
 323                 rc = -EINVAL;
 324                 goto out;
 325         }
 326
 327         bsize = le32_to_cpu(j_sb->s_bsize);
 328 #ifdef _JFS_4K
 329         if (bsize != PSIZE) {
 330                 jfs_err("Currently only 4K block size supported!");
 331                 rc = -EINVAL;
 332                 goto out;
 333         }
 334 #endif                          /* _JFS_4K */
 335
 336         jfs_info("superblock: flag:0x%08x state:0x%08x size:0x%Lx",
 337                  le32_to_cpu(j_sb->s_flag), le32_to_cpu(j_sb->s_state),
 338                  (unsigned long long) le64_to_cpu(j_sb->s_size));
 339
 340         /* validate the descriptors for Secondary AIM and AIT */
 341         if ((j_sb->s_flag & cpu_to_le32(JFS_BAD_SAIT)) !=
 342             cpu_to_le32(JFS_BAD_SAIT)) {
 343                 expected_AIM_bytesize = 2 * PSIZE;
 344                 AIM_bytesize = lengthPXD(&(j_sb->s_aim2)) * bsize;
 345                 expected_AIT_bytesize = 4 * PSIZE;
 346                 AIT_bytesize = lengthPXD(&(j_sb->s_ait2)) * bsize;
 347                 AIM_byte_addr = addressPXD(&(j_sb->s_aim2)) * bsize;
 348                 AIT_byte_addr = addressPXD(&(j_sb->s_ait2)) * bsize;
 349                 byte_addr_diff0 = AIT_byte_addr - AIM_byte_addr;
 350                 fsckwsp_addr = addressPXD(&(j_sb->s_fsckpxd)) * bsize;
 351                 byte_addr_diff1 = fsckwsp_addr - AIT_byte_addr;
 352                 if ((AIM_bytesize != expected_AIM_bytesize) ||
 353                     (AIT_bytesize != expected_AIT_bytesize) ||
 354                     (byte_addr_diff0 != AIM_bytesize) ||
 355                     (byte_addr_diff1 <= AIT_bytesize))
 356                         j_sb->s_flag |= cpu_to_le32(JFS_BAD_SAIT);
 357         }
 358
 359         if ((j_sb->s_flag & cpu_to_le32(JFS_GROUPCOMMIT)) !=
 360             cpu_to_le32(JFS_GROUPCOMMIT))
 361                 j_sb->s_flag |= cpu_to_le32(JFS_GROUPCOMMIT);
 362
 363         /* validate fs state */
 364         if (j_sb->s_state != cpu_to_le32(FM_CLEAN) &&
 365             !(sb->s_flags & MS_RDONLY)) {
 366                 jfs_err("jfs_mount: Mount Failure: File System Dirty.");
 367                 rc = -EINVAL;
 368                 goto out;
 369         }
 370
 371         sbi->state = le32_to_cpu(j_sb->s_state);
 372         sbi->mntflag = le32_to_cpu(j_sb->s_flag);
 373
 374         /*
 375          * JFS always does I/O by 4K pages.  Don't tell the buffer cache
 376          * that we use anything else (leave s_blocksize alone).
 377          */
 378         sbi->bsize = bsize;
 379         sbi->l2bsize = le16_to_cpu(j_sb->s_l2bsize);
 380
 381         /*
 382          * For now, ignore s_pbsize, l2bfactor.  All I/O going through buffer
 383          * cache.
 384          */
 385         sbi->nbperpage = PSIZE >> sbi->l2bsize;
 386         sbi->l2nbperpage = L2PSIZE - sbi->l2bsize;
 387         sbi->l2niperblk = sbi->l2bsize - L2DISIZE;
 388         if (sbi->mntflag & JFS_INLINELOG)
 389                 sbi->logpxd = j_sb->s_logpxd;
 390         else {
 391                 sbi->logdev = new_decode_dev(le32_to_cpu(j_sb->s_logdev));
 392                 memcpy(sbi->uuid, j_sb->s_uuid, sizeof(sbi->uuid));
 393                 memcpy(sbi->loguuid, j_sb->s_loguuid, sizeof(sbi->uuid));
 394         }
 395         sbi->fsckpxd = j_sb->s_fsckpxd;
 396         sbi->ait2 = j_sb->s_ait2;
 397
 398       out:
 399         brelse(bh);
 400         return rc;
 401 }
 402
 403
 404 /*
 405  *      updateSuper()
 406  *
 407  * update synchronously superblock if it is mounted read-write.
 408  */
 409 int updateSuper(struct super_block *sb, uint state)
 410 {
 411         struct jfs_superblock *j_sb;
 412         struct jfs_sb_info *sbi = JFS_SBI(sb);
 413         struct buffer_head *bh;
 414         int rc;
 415
 416         if (sbi->flag & JFS_NOINTEGRITY) {
 417                 if (state == FM_DIRTY) {
 418                         sbi->p_state = state;
 419                         return 0;
 420                 } else if (state == FM_MOUNT) {
 421                         sbi->p_state = sbi->state;
 422                         state = FM_DIRTY;
 423                 } else if (state == FM_CLEAN) {
 424                         state = sbi->p_state;
 425                 } else
 426                         jfs_err("updateSuper: bad state");
 427         } else if (sbi->state == FM_DIRTY)
 428                 return 0;
 429
 430         if ((rc = readSuper(sb, &bh)))
 431                 return rc;
 432
 433         j_sb = (struct jfs_superblock *)bh->b_data;
 434
 435         j_sb->s_state = cpu_to_le32(state);
 436         sbi->state = state;
 437
 438         if (state == FM_MOUNT) {
 439                 /* record log's dev_t and mount serial number */
 440                 j_sb->s_logdev = cpu_to_le32(new_encode_dev(sbi->log->bdev->bd_dev));
 441                 j_sb->s_logserial = cpu_to_le32(sbi->log->serial);
 442         } else if (state == FM_CLEAN) {
 443                 /*
 444                  * If this volume is shared with OS/2, OS/2 will need to
 445                  * recalculate DASD usage, since we don't deal with it.
 446                  */
 447                 if (j_sb->s_flag & cpu_to_le32(JFS_DASD_ENABLED))
 448                         j_sb->s_flag |= cpu_to_le32(JFS_DASD_PRIME);
 449         }
 450
 451         mark_buffer_dirty(bh);
 452         sync_dirty_buffer(bh);
 453         brelse(bh);
 454
 455         return 0;
 456 }
 457
 458
 459 /*
 460  *      readSuper()
 461  *
 462  * read superblock by raw sector address
 463  */
 464 int readSuper(struct super_block *sb, struct buffer_head **bpp)
 465 {
 466         /* read in primary superblock */
 467         *bpp = sb_bread(sb, SUPER1_OFF >> sb->s_blocksize_bits);
 468         if (*bpp)
 469                 return 0;
 470
 471         /* read in secondary/replicated superblock */
 472         *bpp = sb_bread(sb, SUPER2_OFF >> sb->s_blocksize_bits);
 473         if (*bpp)
 474                 return 0;
 475
 476         return -EIO;
 477 }
 478
 479
 480 /*
 481  *      logMOUNT()
 482  *
 483  * function: write a MOUNT log record for file system.
 484  *
 485  * MOUNT record keeps logredo() from processing log records
 486  * for this file system past this point in log.
 487  * it is harmless if mount fails.
 488  *
 489  * note: MOUNT record is at aggregate level, not at fileset level,
 490  * since log records of previous mounts of a fileset
 491  * (e.g., AFTER record of extent allocation) have to be processed
 492  * to update block allocation map at aggregate level.
 493  */
 494 static int logMOUNT(struct super_block *sb)
 495 {
 496         struct jfs_log *log = JFS_SBI(sb)->log;
 497         struct lrd lrd;
 498
 499         lrd.logtid = 0;
 500         lrd.backchain = 0;
 501         lrd.type = cpu_to_le16(LOG_MOUNT);
 502         lrd.length = 0;
 503         lrd.aggregate = cpu_to_le32(new_encode_dev(sb->s_bdev->bd_dev));
 504         lmLog(log, NULL, &lrd, NULL);
 505
 506         return 0;
 507 }