fs/jfs/jfs_mount.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *   Copyright (C) International Business Machines Corp., 2000-2004
   4  */
   5
   6 /*
   7  * Module: jfs_mount.c
   8  *
   9  * note: file system in transition to aggregate/fileset:
  10  *
  11  * file system mount is interpreted as the mount of aggregate,
  12  * if not already mounted, and mount of the single/only fileset in
  13  * the aggregate;
  14  *
  15  * a file system/aggregate is represented by an internal inode
  16  * (aka mount inode) initialized with aggregate superblock;
  17  * each vfs represents a fileset, and points to its "fileset inode
  18  * allocation map inode" (aka fileset inode):
  19  * (an aggregate itself is structured recursively as a filset:
  20  * an internal vfs is constructed and points to its "fileset inode
  21  * allocation map inode" (aka aggregate inode) where each inode
  22  * represents a fileset inode) so that inode number is mapped to
  23  * on-disk inode in uniform way at both aggregate and fileset level;
  24  *
  25  * each vnode/inode of a fileset is linked to its vfs (to facilitate
  26  * per fileset inode operations, e.g., unmount of a fileset, etc.);
  27  * each inode points to the mount inode (to facilitate access to
  28  * per aggregate information, e.g., block size, etc.) as well as
  29  * its file set inode.
  30  *
  31  *   aggregate
  32  *   ipmnt
  33  *   mntvfs -> fileset ipimap+ -> aggregate ipbmap -> aggregate ipaimap;
  34  *             fileset vfs     -> vp(1) <-> ... <-> vp(n) <->vproot;
  35  */
  36
  37 #include <linux/fs.h>
  38 #include <linux/buffer_head.h>
  39 #include <linux/blkdev.h>
  40 #include <linux/log2.h>
  41
  42 #include "jfs_incore.h"
  43 #include "jfs_filsys.h"
  44 #include "jfs_superblock.h"
  45 #include "jfs_dmap.h"
  46 #include "jfs_imap.h"
  47 #include "jfs_metapage.h"
  48 #include "jfs_debug.h"
  49
  50
  51 /*
  52  * forward references
  53  */
  54 static int chkSuper(struct super_block *);
  55 static int logMOUNT(struct super_block *sb);
  56
  57 /*
  58  * NAME:        jfs_mount(sb)
  59  *
  60  * FUNCTION:    vfs_mount()
  61  *
  62  * PARAMETER:   sb      - super block
  63  *
  64  * RETURN:      -EBUSY  - device already mounted or open for write
  65  *              -EBUSY  - cvrdvp already mounted;
  66  *              -EBUSY  - mount table full
  67  *              -ENOTDIR- cvrdvp not directory on a device mount
  68  *              -ENXIO  - device open failure
  69  */
  70 int jfs_mount(struct super_block *sb)
  71 {
  72         int rc = 0;             /* Return code */
  73         struct jfs_sb_info *sbi = JFS_SBI(sb);
  74         struct inode *ipaimap = NULL;
  75         struct inode *ipaimap2 = NULL;
  76         struct inode *ipimap = NULL;
  77         struct inode *ipbmap = NULL;
  78
  79         /*
  80          * read/validate superblock
  81          * (initialize mount inode from the superblock)
  82          */
  83         if ((rc = chkSuper(sb))) {
  84                 goto out;
  85         }
  86
  87         ipaimap = diReadSpecial(sb, AGGREGATE_I, 0);
  88         if (ipaimap == NULL) {
  89                 jfs_err("jfs_mount: Failed to read AGGREGATE_I");
  90                 rc = -EIO;
  91                 goto out;
  92         }
  93         sbi->ipaimap = ipaimap;
  94
  95         jfs_info("jfs_mount: ipaimap:0x%p", ipaimap);
  96
  97         /*
  98          * initialize aggregate inode allocation map
  99          */
 100         if ((rc = diMount(ipaimap))) {
 101                 jfs_err("jfs_mount: diMount(ipaimap) failed w/rc = %d", rc);
 102                 goto err_ipaimap;
 103         }
 104
 105         /*
 106          * open aggregate block allocation map
 107          */
 108         ipbmap = diReadSpecial(sb, BMAP_I, 0);
 109         if (ipbmap == NULL) {
 110                 rc = -EIO;
 111                 goto err_umount_ipaimap;
 112         }
 113
 114         jfs_info("jfs_mount: ipbmap:0x%p", ipbmap);
 115
 116         sbi->ipbmap = ipbmap;
 117
 118         /*
 119          * initialize aggregate block allocation map
 120          */
 121         if ((rc = dbMount(ipbmap))) {
 122                 jfs_err("jfs_mount: dbMount failed w/rc = %d", rc);
 123                 goto err_ipbmap;
 124         }
 125
 126         /*
 127          * open the secondary aggregate inode allocation map
 128          *
 129          * This is a duplicate of the aggregate inode allocation map.
 130          *
 131          * hand craft a vfs in the same fashion as we did to read ipaimap.
 132          * By adding INOSPEREXT (32) to the inode number, we are telling
 133          * diReadSpecial that we are reading from the secondary aggregate
 134          * inode table.  This also creates a unique entry in the inode hash
 135          * table.
 136          */
 137         if ((sbi->mntflag & JFS_BAD_SAIT) == 0) {
 138                 ipaimap2 = diReadSpecial(sb, AGGREGATE_I, 1);
 139                 if (!ipaimap2) {
 140                         jfs_err("jfs_mount: Failed to read AGGREGATE_I");
 141                         rc = -EIO;
 142                         goto err_umount_ipbmap;
 143                 }
 144                 sbi->ipaimap2 = ipaimap2;
 145
 146                 jfs_info("jfs_mount: ipaimap2:0x%p", ipaimap2);
 147
 148                 /*
 149                  * initialize secondary aggregate inode allocation map
 150                  */
 151                 if ((rc = diMount(ipaimap2))) {
 152                         jfs_err("jfs_mount: diMount(ipaimap2) failed, rc = %d",
 153                                 rc);
 154                         goto err_ipaimap2;
 155                 }
 156         } else
 157                 /* Secondary aggregate inode table is not valid */
 158                 sbi->ipaimap2 = NULL;
 159
 160         /*
 161          *      mount (the only/single) fileset
 162          */
 163         /*
 164          * open fileset inode allocation map (aka fileset inode)
 165          */
 166         ipimap = diReadSpecial(sb, FILESYSTEM_I, 0);
 167         if (ipimap == NULL) {
 168                 jfs_err("jfs_mount: Failed to read FILESYSTEM_I");
 169                 /* open fileset secondary inode allocation map */
 170                 rc = -EIO;
 171                 goto err_umount_ipaimap2;
 172         }
 173         jfs_info("jfs_mount: ipimap:0x%p", ipimap);
 174
 175         /* initialize fileset inode allocation map */
 176         if ((rc = diMount(ipimap))) {
 177                 jfs_err("jfs_mount: diMount failed w/rc = %d", rc);
 178                 goto err_ipimap;
 179         }
 180
 181         /* map further access of per fileset inodes by the fileset inode */
 182         sbi->ipimap = ipimap;
 183
 184         return rc;
 185
 186         /*
 187          *      unwind on error
 188          */
 189 err_ipimap:
 190         /* close fileset inode allocation map inode */
 191         diFreeSpecial(ipimap);
 192 err_umount_ipaimap2:
 193         /* close secondary aggregate inode allocation map */
 194         if (ipaimap2)
 195                 diUnmount(ipaimap2, 1);
 196 err_ipaimap2:
 197         /* close aggregate inodes */
 198         if (ipaimap2)
 199                 diFreeSpecial(ipaimap2);
 200 err_umount_ipbmap:      /* close aggregate block allocation map */
 201         dbUnmount(ipbmap, 1);
 202 err_ipbmap:             /* close aggregate inodes */
 203         diFreeSpecial(ipbmap);
 204 err_umount_ipaimap:     /* close aggregate inode allocation map */
 205         diUnmount(ipaimap, 1);
 206 err_ipaimap:            /* close aggregate inodes */
 207         diFreeSpecial(ipaimap);
 208 out:
 209         if (rc)
 210                 jfs_err("Mount JFS Failure: %d", rc);
 211
 212         return rc;
 213 }
 214
 215 /*
 216  * NAME:        jfs_mount_rw(sb, remount)
 217  *
 218  * FUNCTION:    Completes read-write mount, or remounts read-only volume
 219  *              as read-write
 220  */
 221 int jfs_mount_rw(struct super_block *sb, int remount)
 222 {
 223         struct jfs_sb_info *sbi = JFS_SBI(sb);
 224         int rc;
 225
 226         /*
 227          * If we are re-mounting a previously read-only volume, we want to
 228          * re-read the inode and block maps, since fsck.jfs may have updated
 229          * them.
 230          */
 231         if (remount) {
 232                 if (chkSuper(sb) || (sbi->state != FM_CLEAN))
 233                         return -EINVAL;
 234
 235                 truncate_inode_pages(sbi->ipimap->i_mapping, 0);
 236                 truncate_inode_pages(sbi->ipbmap->i_mapping, 0);
 237
 238                 IWRITE_LOCK(sbi->ipimap, RDWRLOCK_IMAP);
 239                 diUnmount(sbi->ipimap, 1);
 240                 if ((rc = diMount(sbi->ipimap))) {
 241                         IWRITE_UNLOCK(sbi->ipimap);
 242                         jfs_err("jfs_mount_rw: diMount failed!");
 243                         return rc;
 244                 }
 245                 IWRITE_UNLOCK(sbi->ipimap);
 246
 247                 dbUnmount(sbi->ipbmap, 1);
 248                 if ((rc = dbMount(sbi->ipbmap))) {
 249                         jfs_err("jfs_mount_rw: dbMount failed!");
 250                         return rc;
 251                 }
 252         }
 253
 254         /*
 255          * open/initialize log
 256          */
 257         if ((rc = lmLogOpen(sb)))
 258                 return rc;
 259
 260         /*
 261          * update file system superblock;
 262          */
 263         if ((rc = updateSuper(sb, FM_MOUNT))) {
 264                 jfs_err("jfs_mount: updateSuper failed w/rc = %d", rc);
 265                 lmLogClose(sb);
 266                 return rc;
 267         }
 268
 269         /*
 270          * write MOUNT log record of the file system
 271          */
 272         logMOUNT(sb);
 273
 274         return rc;
 275 }
 276
 277 /*
 278  *      chkSuper()
 279  *
 280  * validate the superblock of the file system to be mounted and
 281  * get the file system parameters.
 282  *
 283  * returns
 284  *      0 with fragsize set if check successful
 285  *      error code if not successful
 286  */
 287 static int chkSuper(struct super_block *sb)
 288 {
 289         int rc = 0;
 290         struct jfs_sb_info *sbi = JFS_SBI(sb);
 291         struct jfs_superblock *j_sb;
 292         struct buffer_head *bh;
 293         int AIM_bytesize, AIT_bytesize;
 294         int expected_AIM_bytesize, expected_AIT_bytesize;
 295         s64 AIM_byte_addr, AIT_byte_addr, fsckwsp_addr;
 296         s64 byte_addr_diff0, byte_addr_diff1;
 297         s32 bsize;
 298
 299         if ((rc = readSuper(sb, &bh)))
 300                 return rc;
 301         j_sb = (struct jfs_superblock *)bh->b_data;
 302
 303         /*
 304          * validate superblock
 305          */
 306         /* validate fs signature */
 307         if (strncmp(j_sb->s_magic, JFS_MAGIC, 4) ||
 308             le32_to_cpu(j_sb->s_version) > JFS_VERSION) {
 309                 rc = -EINVAL;
 310                 goto out;
 311         }
 312
 313         bsize = le32_to_cpu(j_sb->s_bsize);
 314         if (bsize != PSIZE) {
 315                 jfs_err("Only 4K block size supported!");
 316                 rc = -EINVAL;
 317                 goto out;
 318         }
 319
 320         jfs_info("superblock: flag:0x%08x state:0x%08x size:0x%Lx",
 321                  le32_to_cpu(j_sb->s_flag), le32_to_cpu(j_sb->s_state),
 322                  (unsigned long long) le64_to_cpu(j_sb->s_size));
 323
 324         /* validate the descriptors for Secondary AIM and AIT */
 325         if ((j_sb->s_flag & cpu_to_le32(JFS_BAD_SAIT)) !=
 326             cpu_to_le32(JFS_BAD_SAIT)) {
 327                 expected_AIM_bytesize = 2 * PSIZE;
 328                 AIM_bytesize = lengthPXD(&(j_sb->s_aim2)) * bsize;
 329                 expected_AIT_bytesize = 4 * PSIZE;
 330                 AIT_bytesize = lengthPXD(&(j_sb->s_ait2)) * bsize;
 331                 AIM_byte_addr = addressPXD(&(j_sb->s_aim2)) * bsize;
 332                 AIT_byte_addr = addressPXD(&(j_sb->s_ait2)) * bsize;
 333                 byte_addr_diff0 = AIT_byte_addr - AIM_byte_addr;
 334                 fsckwsp_addr = addressPXD(&(j_sb->s_fsckpxd)) * bsize;
 335                 byte_addr_diff1 = fsckwsp_addr - AIT_byte_addr;
 336                 if ((AIM_bytesize != expected_AIM_bytesize) ||
 337                     (AIT_bytesize != expected_AIT_bytesize) ||
 338                     (byte_addr_diff0 != AIM_bytesize) ||
 339                     (byte_addr_diff1 <= AIT_bytesize))
 340                         j_sb->s_flag |= cpu_to_le32(JFS_BAD_SAIT);
 341         }
 342
 343         if ((j_sb->s_flag & cpu_to_le32(JFS_GROUPCOMMIT)) !=
 344             cpu_to_le32(JFS_GROUPCOMMIT))
 345                 j_sb->s_flag |= cpu_to_le32(JFS_GROUPCOMMIT);
 346
 347         /* validate fs state */
 348         if (j_sb->s_state != cpu_to_le32(FM_CLEAN) &&
 349             !sb_rdonly(sb)) {
 350                 jfs_err("jfs_mount: Mount Failure: File System Dirty.");
 351                 rc = -EINVAL;
 352                 goto out;
 353         }
 354
 355         sbi->state = le32_to_cpu(j_sb->s_state);
 356         sbi->mntflag = le32_to_cpu(j_sb->s_flag);
 357
 358         /*
 359          * JFS always does I/O by 4K pages.  Don't tell the buffer cache
 360          * that we use anything else (leave s_blocksize alone).
 361          */
 362         sbi->bsize = bsize;
 363         sbi->l2bsize = le16_to_cpu(j_sb->s_l2bsize);
 364
 365         /* check some fields for possible corruption */
 366         if (sbi->l2bsize != ilog2((u32)bsize) ||
 367             j_sb->pad != 0 ||
 368             le32_to_cpu(j_sb->s_state) > FM_STATE_MAX) {
 369                 rc = -EINVAL;
 370                 jfs_err("jfs_mount: Mount Failure: superblock is corrupt!");
 371                 goto out;
 372         }
 373
 374         /*
 375          * For now, ignore s_pbsize, l2bfactor.  All I/O going through buffer
 376          * cache.
 377          */
 378         sbi->nbperpage = PSIZE >> sbi->l2bsize;
 379         sbi->l2nbperpage = L2PSIZE - sbi->l2bsize;
 380         sbi->l2niperblk = sbi->l2bsize - L2DISIZE;
 381         if (sbi->mntflag & JFS_INLINELOG)
 382                 sbi->logpxd = j_sb->s_logpxd;
 383         else {
 384                 sbi->logdev = new_decode_dev(le32_to_cpu(j_sb->s_logdev));
 385                 uuid_copy(&sbi->uuid, &j_sb->s_uuid);
 386                 uuid_copy(&sbi->loguuid, &j_sb->s_loguuid);
 387         }
 388         sbi->fsckpxd = j_sb->s_fsckpxd;
 389         sbi->ait2 = j_sb->s_ait2;
 390
 391       out:
 392         brelse(bh);
 393         return rc;
 394 }
 395
 396
 397 /*
 398  *      updateSuper()
 399  *
 400  * update synchronously superblock if it is mounted read-write.
 401  */
 402 int updateSuper(struct super_block *sb, uint state)
 403 {
 404         struct jfs_superblock *j_sb;
 405         struct jfs_sb_info *sbi = JFS_SBI(sb);
 406         struct buffer_head *bh;
 407         int rc;
 408
 409         if (sbi->flag & JFS_NOINTEGRITY) {
 410                 if (state == FM_DIRTY) {
 411                         sbi->p_state = state;
 412                         return 0;
 413                 } else if (state == FM_MOUNT) {
 414                         sbi->p_state = sbi->state;
 415                         state = FM_DIRTY;
 416                 } else if (state == FM_CLEAN) {
 417                         state = sbi->p_state;
 418                 } else
 419                         jfs_err("updateSuper: bad state");
 420         } else if (sbi->state == FM_DIRTY)
 421                 return 0;
 422
 423         if ((rc = readSuper(sb, &bh)))
 424                 return rc;
 425
 426         j_sb = (struct jfs_superblock *)bh->b_data;
 427
 428         j_sb->s_state = cpu_to_le32(state);
 429         sbi->state = state;
 430
 431         if (state == FM_MOUNT) {
 432                 /* record log's dev_t and mount serial number */
 433                 j_sb->s_logdev = cpu_to_le32(
 434                         new_encode_dev(file_bdev(sbi->log->bdev_file)->bd_dev));
 435                 j_sb->s_logserial = cpu_to_le32(sbi->log->serial);
 436         } else if (state == FM_CLEAN) {
 437                 /*
 438                  * If this volume is shared with OS/2, OS/2 will need to
 439                  * recalculate DASD usage, since we don't deal with it.
 440                  */
 441                 if (j_sb->s_flag & cpu_to_le32(JFS_DASD_ENABLED))
 442                         j_sb->s_flag |= cpu_to_le32(JFS_DASD_PRIME);
 443         }
 444
 445         mark_buffer_dirty(bh);
 446         sync_dirty_buffer(bh);
 447         brelse(bh);
 448
 449         return 0;
 450 }
 451
 452
 453 /*
 454  *      readSuper()
 455  *
 456  * read superblock by raw sector address
 457  */
 458 int readSuper(struct super_block *sb, struct buffer_head **bpp)
 459 {
 460         /* read in primary superblock */
 461         *bpp = sb_bread(sb, SUPER1_OFF >> sb->s_blocksize_bits);
 462         if (*bpp)
 463                 return 0;
 464
 465         /* read in secondary/replicated superblock */
 466         *bpp = sb_bread(sb, SUPER2_OFF >> sb->s_blocksize_bits);
 467         if (*bpp)
 468                 return 0;
 469
 470         return -EIO;
 471 }
 472
 473
 474 /*
 475  *      logMOUNT()
 476  *
 477  * function: write a MOUNT log record for file system.
 478  *
 479  * MOUNT record keeps logredo() from processing log records
 480  * for this file system past this point in log.
 481  * it is harmless if mount fails.
 482  *
 483  * note: MOUNT record is at aggregate level, not at fileset level,
 484  * since log records of previous mounts of a fileset
 485  * (e.g., AFTER record of extent allocation) have to be processed
 486  * to update block allocation map at aggregate level.
 487  */
 488 static int logMOUNT(struct super_block *sb)
 489 {
 490         struct jfs_log *log = JFS_SBI(sb)->log;
 491         struct lrd lrd;
 492
 493         lrd.logtid = 0;
 494         lrd.backchain = 0;
 495         lrd.type = cpu_to_le16(LOG_MOUNT);
 496         lrd.length = 0;
 497         lrd.aggregate = cpu_to_le32(new_encode_dev(sb->s_bdev->bd_dev));
 498         lmLog(log, NULL, &lrd, NULL);
 499
 500         return 0;
 501 }