fs/ext2/super.c

   1 /*
   2  *  linux/fs/ext2/super.c
   3  *
   4  * Copyright (C) 1992, 1993, 1994, 1995
   5  * Remy Card (card@masi.ibp.fr)
   6  * Laboratoire MASI - Institut Blaise Pascal
   7  * Universite Pierre et Marie Curie (Paris VI)
   8  *
   9  *  from
  10  *
  11  *  linux/fs/minix/inode.c
  12  *
  13  *  Copyright (C) 1991, 1992  Linus Torvalds
  14  *
  15  *  Big-endian to little-endian byte-swapping/bitmaps by
  16  *        David S. Miller (davem@caip.rutgers.edu), 1995
  17  */
  18
  19 #include <linux/module.h>
  20 #include <linux/string.h>
  21 #include <linux/fs.h>
  22 #include <linux/slab.h>
  23 #include <linux/init.h>
  24 #include <linux/blkdev.h>
  25 #include <linux/parser.h>
  26 #include <linux/random.h>
  27 #include <linux/buffer_head.h>
  28 #include <linux/exportfs.h>
  29 #include <linux/vfs.h>
  30 #include <linux/seq_file.h>
  31 #include <linux/mount.h>
  32 #include <linux/log2.h>
  33 #include <linux/quotaops.h>
  34 #include <linux/uaccess.h>
  35 #include <linux/dax.h>
  36 #include <linux/iversion.h>
  37 #include "ext2.h"
  38 #include "xattr.h"
  39 #include "acl.h"
  40
  41 static void ext2_write_super(struct super_block *sb);
  42 static int ext2_remount (struct super_block * sb, int * flags, char * data);
  43 static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf);
  44 static int ext2_sync_fs(struct super_block *sb, int wait);
  45 static int ext2_freeze(struct super_block *sb);
  46 static int ext2_unfreeze(struct super_block *sb);
  47
  48 void ext2_error(struct super_block *sb, const char *function,
  49                 const char *fmt, ...)
  50 {
  51         struct va_format vaf;
  52         va_list args;
  53         struct ext2_sb_info *sbi = EXT2_SB(sb);
  54         struct ext2_super_block *es = sbi->s_es;
  55
  56         if (!sb_rdonly(sb)) {
  57                 spin_lock(&sbi->s_lock);
  58                 sbi->s_mount_state |= EXT2_ERROR_FS;
  59                 es->s_state |= cpu_to_le16(EXT2_ERROR_FS);
  60                 spin_unlock(&sbi->s_lock);
  61                 ext2_sync_super(sb, es, 1);
  62         }
  63
  64         va_start(args, fmt);
  65
  66         vaf.fmt = fmt;
  67         vaf.va = &args;
  68
  69         printk(KERN_CRIT "EXT2-fs (%s): error: %s: %pV\n",
  70                sb->s_id, function, &vaf);
  71
  72         va_end(args);
  73
  74         if (test_opt(sb, ERRORS_PANIC))
  75                 panic("EXT2-fs: panic from previous error\n");
  76         if (test_opt(sb, ERRORS_RO)) {
  77                 ext2_msg(sb, KERN_CRIT,
  78                              "error: remounting filesystem read-only");
  79                 sb->s_flags |= SB_RDONLY;
  80         }
  81 }
  82
  83 void ext2_msg(struct super_block *sb, const char *prefix,
  84                 const char *fmt, ...)
  85 {
  86         struct va_format vaf;
  87         va_list args;
  88
  89         va_start(args, fmt);
  90
  91         vaf.fmt = fmt;
  92         vaf.va = &args;
  93
  94         printk("%sEXT2-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
  95
  96         va_end(args);
  97 }
  98
  99 /*
 100  * This must be called with sbi->s_lock held.
 101  */
 102 void ext2_update_dynamic_rev(struct super_block *sb)
 103 {
 104         struct ext2_super_block *es = EXT2_SB(sb)->s_es;
 105
 106         if (le32_to_cpu(es->s_rev_level) > EXT2_GOOD_OLD_REV)
 107                 return;
 108
 109         ext2_msg(sb, KERN_WARNING,
 110                      "warning: updating to rev %d because of "
 111                      "new feature flag, running e2fsck is recommended",
 112                      EXT2_DYNAMIC_REV);
 113
 114         es->s_first_ino = cpu_to_le32(EXT2_GOOD_OLD_FIRST_INO);
 115         es->s_inode_size = cpu_to_le16(EXT2_GOOD_OLD_INODE_SIZE);
 116         es->s_rev_level = cpu_to_le32(EXT2_DYNAMIC_REV);
 117         /* leave es->s_feature_*compat flags alone */
 118         /* es->s_uuid will be set by e2fsck if empty */
 119
 120         /*
 121          * The rest of the superblock fields should be zero, and if not it
 122          * means they are likely already in use, so leave them alone.  We
 123          * can leave it up to e2fsck to clean up any inconsistencies there.
 124          */
 125 }
 126
 127 #ifdef CONFIG_QUOTA
 128 static int ext2_quota_off(struct super_block *sb, int type);
 129
 130 static void ext2_quota_off_umount(struct super_block *sb)
 131 {
 132         int type;
 133
 134         for (type = 0; type < MAXQUOTAS; type++)
 135                 ext2_quota_off(sb, type);
 136 }
 137 #else
 138 static inline void ext2_quota_off_umount(struct super_block *sb)
 139 {
 140 }
 141 #endif
 142
 143 static void ext2_put_super (struct super_block * sb)
 144 {
 145         int db_count;
 146         int i;
 147         struct ext2_sb_info *sbi = EXT2_SB(sb);
 148
 149         ext2_quota_off_umount(sb);
 150
 151         if (sbi->s_ea_block_cache) {
 152                 ext2_xattr_destroy_cache(sbi->s_ea_block_cache);
 153                 sbi->s_ea_block_cache = NULL;
 154         }
 155         if (!sb_rdonly(sb)) {
 156                 struct ext2_super_block *es = sbi->s_es;
 157
 158                 spin_lock(&sbi->s_lock);
 159                 es->s_state = cpu_to_le16(sbi->s_mount_state);
 160                 spin_unlock(&sbi->s_lock);
 161                 ext2_sync_super(sb, es, 1);
 162         }
 163         db_count = sbi->s_gdb_count;
 164         for (i = 0; i < db_count; i++)
 165                 if (sbi->s_group_desc[i])
 166                         brelse (sbi->s_group_desc[i]);
 167         kfree(sbi->s_group_desc);
 168         kfree(sbi->s_debts);
 169         percpu_counter_destroy(&sbi->s_freeblocks_counter);
 170         percpu_counter_destroy(&sbi->s_freeinodes_counter);
 171         percpu_counter_destroy(&sbi->s_dirs_counter);
 172         brelse (sbi->s_sbh);
 173         sb->s_fs_info = NULL;
 174         kfree(sbi->s_blockgroup_lock);
 175         fs_put_dax(sbi->s_daxdev);
 176         kfree(sbi);
 177 }
 178
 179 static struct kmem_cache * ext2_inode_cachep;
 180
 181 static struct inode *ext2_alloc_inode(struct super_block *sb)
 182 {
 183         struct ext2_inode_info *ei;
 184         ei = kmem_cache_alloc(ext2_inode_cachep, GFP_KERNEL);
 185         if (!ei)
 186                 return NULL;
 187         ei->i_block_alloc_info = NULL;
 188         inode_set_iversion(&ei->vfs_inode, 1);
 189 #ifdef CONFIG_QUOTA
 190         memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
 191 #endif
 192
 193         return &ei->vfs_inode;
 194 }
 195
 196 static void ext2_i_callback(struct rcu_head *head)
 197 {
 198         struct inode *inode = container_of(head, struct inode, i_rcu);
 199         kmem_cache_free(ext2_inode_cachep, EXT2_I(inode));
 200 }
 201
 202 static void ext2_destroy_inode(struct inode *inode)
 203 {
 204         call_rcu(&inode->i_rcu, ext2_i_callback);
 205 }
 206
 207 static void init_once(void *foo)
 208 {
 209         struct ext2_inode_info *ei = (struct ext2_inode_info *) foo;
 210
 211         rwlock_init(&ei->i_meta_lock);
 212 #ifdef CONFIG_EXT2_FS_XATTR
 213         init_rwsem(&ei->xattr_sem);
 214 #endif
 215         mutex_init(&ei->truncate_mutex);
 216 #ifdef CONFIG_FS_DAX
 217         init_rwsem(&ei->dax_sem);
 218 #endif
 219         inode_init_once(&ei->vfs_inode);
 220 }
 221
 222 static int __init init_inodecache(void)
 223 {
 224         ext2_inode_cachep = kmem_cache_create("ext2_inode_cache",
 225                                              sizeof(struct ext2_inode_info),
 226                                              0, (SLAB_RECLAIM_ACCOUNT|
 227                                                 SLAB_MEM_SPREAD|SLAB_ACCOUNT),
 228                                              init_once);
 229         if (ext2_inode_cachep == NULL)
 230                 return -ENOMEM;
 231         return 0;
 232 }
 233
 234 static void destroy_inodecache(void)
 235 {
 236         /*
 237          * Make sure all delayed rcu free inodes are flushed before we
 238          * destroy cache.
 239          */
 240         rcu_barrier();
 241         kmem_cache_destroy(ext2_inode_cachep);
 242 }
 243
 244 static int ext2_show_options(struct seq_file *seq, struct dentry *root)
 245 {
 246         struct super_block *sb = root->d_sb;
 247         struct ext2_sb_info *sbi = EXT2_SB(sb);
 248         struct ext2_super_block *es = sbi->s_es;
 249         unsigned long def_mount_opts;
 250
 251         spin_lock(&sbi->s_lock);
 252         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
 253
 254         if (sbi->s_sb_block != 1)
 255                 seq_printf(seq, ",sb=%lu", sbi->s_sb_block);
 256         if (test_opt(sb, MINIX_DF))
 257                 seq_puts(seq, ",minixdf");
 258         if (test_opt(sb, GRPID))
 259                 seq_puts(seq, ",grpid");
 260         if (!test_opt(sb, GRPID) && (def_mount_opts & EXT2_DEFM_BSDGROUPS))
 261                 seq_puts(seq, ",nogrpid");
 262         if (!uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT2_DEF_RESUID)) ||
 263             le16_to_cpu(es->s_def_resuid) != EXT2_DEF_RESUID) {
 264                 seq_printf(seq, ",resuid=%u",
 265                                 from_kuid_munged(&init_user_ns, sbi->s_resuid));
 266         }
 267         if (!gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT2_DEF_RESGID)) ||
 268             le16_to_cpu(es->s_def_resgid) != EXT2_DEF_RESGID) {
 269                 seq_printf(seq, ",resgid=%u",
 270                                 from_kgid_munged(&init_user_ns, sbi->s_resgid));
 271         }
 272         if (test_opt(sb, ERRORS_RO)) {
 273                 int def_errors = le16_to_cpu(es->s_errors);
 274
 275                 if (def_errors == EXT2_ERRORS_PANIC ||
 276                     def_errors == EXT2_ERRORS_CONTINUE) {
 277                         seq_puts(seq, ",errors=remount-ro");
 278                 }
 279         }
 280         if (test_opt(sb, ERRORS_CONT))
 281                 seq_puts(seq, ",errors=continue");
 282         if (test_opt(sb, ERRORS_PANIC))
 283                 seq_puts(seq, ",errors=panic");
 284         if (test_opt(sb, NO_UID32))
 285                 seq_puts(seq, ",nouid32");
 286         if (test_opt(sb, DEBUG))
 287                 seq_puts(seq, ",debug");
 288         if (test_opt(sb, OLDALLOC))
 289                 seq_puts(seq, ",oldalloc");
 290
 291 #ifdef CONFIG_EXT2_FS_XATTR
 292         if (test_opt(sb, XATTR_USER))
 293                 seq_puts(seq, ",user_xattr");
 294         if (!test_opt(sb, XATTR_USER) &&
 295             (def_mount_opts & EXT2_DEFM_XATTR_USER)) {
 296                 seq_puts(seq, ",nouser_xattr");
 297         }
 298 #endif
 299
 300 #ifdef CONFIG_EXT2_FS_POSIX_ACL
 301         if (test_opt(sb, POSIX_ACL))
 302                 seq_puts(seq, ",acl");
 303         if (!test_opt(sb, POSIX_ACL) && (def_mount_opts & EXT2_DEFM_ACL))
 304                 seq_puts(seq, ",noacl");
 305 #endif
 306
 307         if (test_opt(sb, NOBH))
 308                 seq_puts(seq, ",nobh");
 309
 310 #if defined(CONFIG_QUOTA)
 311         if (sbi->s_mount_opt & EXT2_MOUNT_USRQUOTA)
 312                 seq_puts(seq, ",usrquota");
 313
 314         if (sbi->s_mount_opt & EXT2_MOUNT_GRPQUOTA)
 315                 seq_puts(seq, ",grpquota");
 316 #endif
 317
 318 #ifdef CONFIG_FS_DAX
 319         if (sbi->s_mount_opt & EXT2_MOUNT_XIP)
 320                 seq_puts(seq, ",xip");
 321         if (sbi->s_mount_opt & EXT2_MOUNT_DAX)
 322                 seq_puts(seq, ",dax");
 323 #endif
 324
 325         if (!test_opt(sb, RESERVATION))
 326                 seq_puts(seq, ",noreservation");
 327
 328         spin_unlock(&sbi->s_lock);
 329         return 0;
 330 }
 331
 332 #ifdef CONFIG_QUOTA
 333 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, size_t len, loff_t off);
 334 static ssize_t ext2_quota_write(struct super_block *sb, int type, const char *data, size_t len, loff_t off);
 335 static int ext2_quota_on(struct super_block *sb, int type, int format_id,
 336                          const struct path *path);
 337 static struct dquot **ext2_get_dquots(struct inode *inode)
 338 {
 339         return EXT2_I(inode)->i_dquot;
 340 }
 341
 342 static const struct quotactl_ops ext2_quotactl_ops = {
 343         .quota_on       = ext2_quota_on,
 344         .quota_off      = ext2_quota_off,
 345         .quota_sync     = dquot_quota_sync,
 346         .get_state      = dquot_get_state,
 347         .set_info       = dquot_set_dqinfo,
 348         .get_dqblk      = dquot_get_dqblk,
 349         .set_dqblk      = dquot_set_dqblk,
 350         .get_nextdqblk  = dquot_get_next_dqblk,
 351 };
 352 #endif
 353
 354 static const struct super_operations ext2_sops = {
 355         .alloc_inode    = ext2_alloc_inode,
 356         .destroy_inode  = ext2_destroy_inode,
 357         .write_inode    = ext2_write_inode,
 358         .evict_inode    = ext2_evict_inode,
 359         .put_super      = ext2_put_super,
 360         .sync_fs        = ext2_sync_fs,
 361         .freeze_fs      = ext2_freeze,
 362         .unfreeze_fs    = ext2_unfreeze,
 363         .statfs         = ext2_statfs,
 364         .remount_fs     = ext2_remount,
 365         .show_options   = ext2_show_options,
 366 #ifdef CONFIG_QUOTA
 367         .quota_read     = ext2_quota_read,
 368         .quota_write    = ext2_quota_write,
 369         .get_dquots     = ext2_get_dquots,
 370 #endif
 371 };
 372
 373 static struct inode *ext2_nfs_get_inode(struct super_block *sb,
 374                 u64 ino, u32 generation)
 375 {
 376         struct inode *inode;
 377
 378         if (ino < EXT2_FIRST_INO(sb) && ino != EXT2_ROOT_INO)
 379                 return ERR_PTR(-ESTALE);
 380         if (ino > le32_to_cpu(EXT2_SB(sb)->s_es->s_inodes_count))
 381                 return ERR_PTR(-ESTALE);
 382
 383         /*
 384          * ext2_iget isn't quite right if the inode is currently unallocated!
 385          * However ext2_iget currently does appropriate checks to handle stale
 386          * inodes so everything is OK.
 387          */
 388         inode = ext2_iget(sb, ino);
 389         if (IS_ERR(inode))
 390                 return ERR_CAST(inode);
 391         if (generation && inode->i_generation != generation) {
 392                 /* we didn't find the right inode.. */
 393                 iput(inode);
 394                 return ERR_PTR(-ESTALE);
 395         }
 396         return inode;
 397 }
 398
 399 static struct dentry *ext2_fh_to_dentry(struct super_block *sb, struct fid *fid,
 400                 int fh_len, int fh_type)
 401 {
 402         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
 403                                     ext2_nfs_get_inode);
 404 }
 405
 406 static struct dentry *ext2_fh_to_parent(struct super_block *sb, struct fid *fid,
 407                 int fh_len, int fh_type)
 408 {
 409         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
 410                                     ext2_nfs_get_inode);
 411 }
 412
 413 static const struct export_operations ext2_export_ops = {
 414         .fh_to_dentry = ext2_fh_to_dentry,
 415         .fh_to_parent = ext2_fh_to_parent,
 416         .get_parent = ext2_get_parent,
 417 };
 418
 419 static unsigned long get_sb_block(void **data)
 420 {
 421         unsigned long   sb_block;
 422         char            *options = (char *) *data;
 423
 424         if (!options || strncmp(options, "sb=", 3) != 0)
 425                 return 1;       /* Default location */
 426         options += 3;
 427         sb_block = simple_strtoul(options, &options, 0);
 428         if (*options && *options != ',') {
 429                 printk("EXT2-fs: Invalid sb specification: %s\n",
 430                        (char *) *data);
 431                 return 1;
 432         }
 433         if (*options == ',')
 434                 options++;
 435         *data = (void *) options;
 436         return sb_block;
 437 }
 438
 439 enum {
 440         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
 441         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic,
 442         Opt_err_ro, Opt_nouid32, Opt_nocheck, Opt_debug,
 443         Opt_oldalloc, Opt_orlov, Opt_nobh, Opt_user_xattr, Opt_nouser_xattr,
 444         Opt_acl, Opt_noacl, Opt_xip, Opt_dax, Opt_ignore, Opt_err, Opt_quota,
 445         Opt_usrquota, Opt_grpquota, Opt_reservation, Opt_noreservation
 446 };
 447
 448 static const match_table_t tokens = {
 449         {Opt_bsd_df, "bsddf"},
 450         {Opt_minix_df, "minixdf"},
 451         {Opt_grpid, "grpid"},
 452         {Opt_grpid, "bsdgroups"},
 453         {Opt_nogrpid, "nogrpid"},
 454         {Opt_nogrpid, "sysvgroups"},
 455         {Opt_resgid, "resgid=%u"},
 456         {Opt_resuid, "resuid=%u"},
 457         {Opt_sb, "sb=%u"},
 458         {Opt_err_cont, "errors=continue"},
 459         {Opt_err_panic, "errors=panic"},
 460         {Opt_err_ro, "errors=remount-ro"},
 461         {Opt_nouid32, "nouid32"},
 462         {Opt_nocheck, "check=none"},
 463         {Opt_nocheck, "nocheck"},
 464         {Opt_debug, "debug"},
 465         {Opt_oldalloc, "oldalloc"},
 466         {Opt_orlov, "orlov"},
 467         {Opt_nobh, "nobh"},
 468         {Opt_user_xattr, "user_xattr"},
 469         {Opt_nouser_xattr, "nouser_xattr"},
 470         {Opt_acl, "acl"},
 471         {Opt_noacl, "noacl"},
 472         {Opt_xip, "xip"},
 473         {Opt_dax, "dax"},
 474         {Opt_grpquota, "grpquota"},
 475         {Opt_ignore, "noquota"},
 476         {Opt_quota, "quota"},
 477         {Opt_usrquota, "usrquota"},
 478         {Opt_reservation, "reservation"},
 479         {Opt_noreservation, "noreservation"},
 480         {Opt_err, NULL}
 481 };
 482
 483 static int parse_options(char *options, struct super_block *sb,
 484                          struct ext2_mount_options *opts)
 485 {
 486         char *p;
 487         substring_t args[MAX_OPT_ARGS];
 488         int option;
 489         kuid_t uid;
 490         kgid_t gid;
 491
 492         if (!options)
 493                 return 1;
 494
 495         while ((p = strsep (&options, ",")) != NULL) {
 496                 int token;
 497                 if (!*p)
 498                         continue;
 499
 500                 token = match_token(p, tokens, args);
 501                 switch (token) {
 502                 case Opt_bsd_df:
 503                         clear_opt (opts->s_mount_opt, MINIX_DF);
 504                         break;
 505                 case Opt_minix_df:
 506                         set_opt (opts->s_mount_opt, MINIX_DF);
 507                         break;
 508                 case Opt_grpid:
 509                         set_opt (opts->s_mount_opt, GRPID);
 510                         break;
 511                 case Opt_nogrpid:
 512                         clear_opt (opts->s_mount_opt, GRPID);
 513                         break;
 514                 case Opt_resuid:
 515                         if (match_int(&args[0], &option))
 516                                 return 0;
 517                         uid = make_kuid(current_user_ns(), option);
 518                         if (!uid_valid(uid)) {
 519                                 ext2_msg(sb, KERN_ERR, "Invalid uid value %d", option);
 520                                 return 0;
 521
 522                         }
 523                         opts->s_resuid = uid;
 524                         break;
 525                 case Opt_resgid:
 526                         if (match_int(&args[0], &option))
 527                                 return 0;
 528                         gid = make_kgid(current_user_ns(), option);
 529                         if (!gid_valid(gid)) {
 530                                 ext2_msg(sb, KERN_ERR, "Invalid gid value %d", option);
 531                                 return 0;
 532                         }
 533                         opts->s_resgid = gid;
 534                         break;
 535                 case Opt_sb:
 536                         /* handled by get_sb_block() instead of here */
 537                         /* *sb_block = match_int(&args[0]); */
 538                         break;
 539                 case Opt_err_panic:
 540                         clear_opt (opts->s_mount_opt, ERRORS_CONT);
 541                         clear_opt (opts->s_mount_opt, ERRORS_RO);
 542                         set_opt (opts->s_mount_opt, ERRORS_PANIC);
 543                         break;
 544                 case Opt_err_ro:
 545                         clear_opt (opts->s_mount_opt, ERRORS_CONT);
 546                         clear_opt (opts->s_mount_opt, ERRORS_PANIC);
 547                         set_opt (opts->s_mount_opt, ERRORS_RO);
 548                         break;
 549                 case Opt_err_cont:
 550                         clear_opt (opts->s_mount_opt, ERRORS_RO);
 551                         clear_opt (opts->s_mount_opt, ERRORS_PANIC);
 552                         set_opt (opts->s_mount_opt, ERRORS_CONT);
 553                         break;
 554                 case Opt_nouid32:
 555                         set_opt (opts->s_mount_opt, NO_UID32);
 556                         break;
 557                 case Opt_nocheck:
 558                         clear_opt (opts->s_mount_opt, CHECK);
 559                         break;
 560                 case Opt_debug:
 561                         set_opt (opts->s_mount_opt, DEBUG);
 562                         break;
 563                 case Opt_oldalloc:
 564                         set_opt (opts->s_mount_opt, OLDALLOC);
 565                         break;
 566                 case Opt_orlov:
 567                         clear_opt (opts->s_mount_opt, OLDALLOC);
 568                         break;
 569                 case Opt_nobh:
 570                         set_opt (opts->s_mount_opt, NOBH);
 571                         break;
 572 #ifdef CONFIG_EXT2_FS_XATTR
 573                 case Opt_user_xattr:
 574                         set_opt (opts->s_mount_opt, XATTR_USER);
 575                         break;
 576                 case Opt_nouser_xattr:
 577                         clear_opt (opts->s_mount_opt, XATTR_USER);
 578                         break;
 579 #else
 580                 case Opt_user_xattr:
 581                 case Opt_nouser_xattr:
 582                         ext2_msg(sb, KERN_INFO, "(no)user_xattr options"
 583                                 "not supported");
 584                         break;
 585 #endif
 586 #ifdef CONFIG_EXT2_FS_POSIX_ACL
 587                 case Opt_acl:
 588                         set_opt(opts->s_mount_opt, POSIX_ACL);
 589                         break;
 590                 case Opt_noacl:
 591                         clear_opt(opts->s_mount_opt, POSIX_ACL);
 592                         break;
 593 #else
 594                 case Opt_acl:
 595                 case Opt_noacl:
 596                         ext2_msg(sb, KERN_INFO,
 597                                 "(no)acl options not supported");
 598                         break;
 599 #endif
 600                 case Opt_xip:
 601                         ext2_msg(sb, KERN_INFO, "use dax instead of xip");
 602                         set_opt(opts->s_mount_opt, XIP);
 603                         /* Fall through */
 604                 case Opt_dax:
 605 #ifdef CONFIG_FS_DAX
 606                         ext2_msg(sb, KERN_WARNING,
 607                 "DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
 608                         set_opt(opts->s_mount_opt, DAX);
 609 #else
 610                         ext2_msg(sb, KERN_INFO, "dax option not supported");
 611 #endif
 612                         break;
 613
 614 #if defined(CONFIG_QUOTA)
 615                 case Opt_quota:
 616                 case Opt_usrquota:
 617                         set_opt(opts->s_mount_opt, USRQUOTA);
 618                         break;
 619
 620                 case Opt_grpquota:
 621                         set_opt(opts->s_mount_opt, GRPQUOTA);
 622                         break;
 623 #else
 624                 case Opt_quota:
 625                 case Opt_usrquota:
 626                 case Opt_grpquota:
 627                         ext2_msg(sb, KERN_INFO,
 628                                 "quota operations not supported");
 629                         break;
 630 #endif
 631
 632                 case Opt_reservation:
 633                         set_opt(opts->s_mount_opt, RESERVATION);
 634                         ext2_msg(sb, KERN_INFO, "reservations ON");
 635                         break;
 636                 case Opt_noreservation:
 637                         clear_opt(opts->s_mount_opt, RESERVATION);
 638                         ext2_msg(sb, KERN_INFO, "reservations OFF");
 639                         break;
 640                 case Opt_ignore:
 641                         break;
 642                 default:
 643                         return 0;
 644                 }
 645         }
 646         return 1;
 647 }
 648
 649 static int ext2_setup_super (struct super_block * sb,
 650                               struct ext2_super_block * es,
 651                               int read_only)
 652 {
 653         int res = 0;
 654         struct ext2_sb_info *sbi = EXT2_SB(sb);
 655
 656         if (le32_to_cpu(es->s_rev_level) > EXT2_MAX_SUPP_REV) {
 657                 ext2_msg(sb, KERN_ERR,
 658                         "error: revision level too high, "
 659                         "forcing read-only mode");
 660                 res = SB_RDONLY;
 661         }
 662         if (read_only)
 663                 return res;
 664         if (!(sbi->s_mount_state & EXT2_VALID_FS))
 665                 ext2_msg(sb, KERN_WARNING,
 666                         "warning: mounting unchecked fs, "
 667                         "running e2fsck is recommended");
 668         else if ((sbi->s_mount_state & EXT2_ERROR_FS))
 669                 ext2_msg(sb, KERN_WARNING,
 670                         "warning: mounting fs with errors, "
 671                         "running e2fsck is recommended");
 672         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 &&
 673                  le16_to_cpu(es->s_mnt_count) >=
 674                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
 675                 ext2_msg(sb, KERN_WARNING,
 676                         "warning: maximal mount count reached, "
 677                         "running e2fsck is recommended");
 678         else if (le32_to_cpu(es->s_checkinterval) &&
 679                 (le32_to_cpu(es->s_lastcheck) +
 680                         le32_to_cpu(es->s_checkinterval) <= get_seconds()))
 681                 ext2_msg(sb, KERN_WARNING,
 682                         "warning: checktime reached, "
 683                         "running e2fsck is recommended");
 684         if (!le16_to_cpu(es->s_max_mnt_count))
 685                 es->s_max_mnt_count = cpu_to_le16(EXT2_DFL_MAX_MNT_COUNT);
 686         le16_add_cpu(&es->s_mnt_count, 1);
 687         if (test_opt (sb, DEBUG))
 688                 ext2_msg(sb, KERN_INFO, "%s, %s, bs=%lu, fs=%lu, gc=%lu, "
 689                         "bpg=%lu, ipg=%lu, mo=%04lx]",
 690                         EXT2FS_VERSION, EXT2FS_DATE, sb->s_blocksize,
 691                         sbi->s_frag_size,
 692                         sbi->s_groups_count,
 693                         EXT2_BLOCKS_PER_GROUP(sb),
 694                         EXT2_INODES_PER_GROUP(sb),
 695                         sbi->s_mount_opt);
 696         return res;
 697 }
 698
 699 static int ext2_check_descriptors(struct super_block *sb)
 700 {
 701         int i;
 702         struct ext2_sb_info *sbi = EXT2_SB(sb);
 703
 704         ext2_debug ("Checking group descriptors");
 705
 706         for (i = 0; i < sbi->s_groups_count; i++) {
 707                 struct ext2_group_desc *gdp = ext2_get_group_desc(sb, i, NULL);
 708                 ext2_fsblk_t first_block = ext2_group_first_block_no(sb, i);
 709                 ext2_fsblk_t last_block;
 710
 711                 if (i == sbi->s_groups_count - 1)
 712                         last_block = le32_to_cpu(sbi->s_es->s_blocks_count) - 1;
 713                 else
 714                         last_block = first_block +
 715                                 (EXT2_BLOCKS_PER_GROUP(sb) - 1);
 716
 717                 if (le32_to_cpu(gdp->bg_block_bitmap) < first_block ||
 718                     le32_to_cpu(gdp->bg_block_bitmap) > last_block)
 719                 {
 720                         ext2_error (sb, "ext2_check_descriptors",
 721                                     "Block bitmap for group %d"
 722                                     " not in group (block %lu)!",
 723                                     i, (unsigned long) le32_to_cpu(gdp->bg_block_bitmap));
 724                         return 0;
 725                 }
 726                 if (le32_to_cpu(gdp->bg_inode_bitmap) < first_block ||
 727                     le32_to_cpu(gdp->bg_inode_bitmap) > last_block)
 728                 {
 729                         ext2_error (sb, "ext2_check_descriptors",
 730                                     "Inode bitmap for group %d"
 731                                     " not in group (block %lu)!",
 732                                     i, (unsigned long) le32_to_cpu(gdp->bg_inode_bitmap));
 733                         return 0;
 734                 }
 735                 if (le32_to_cpu(gdp->bg_inode_table) < first_block ||
 736                     le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group - 1 >
 737                     last_block)
 738                 {
 739                         ext2_error (sb, "ext2_check_descriptors",
 740                                     "Inode table for group %d"
 741                                     " not in group (block %lu)!",
 742                                     i, (unsigned long) le32_to_cpu(gdp->bg_inode_table));
 743                         return 0;
 744                 }
 745         }
 746         return 1;
 747 }
 748
 749 /*
 750  * Maximal file size.  There is a direct, and {,double-,triple-}indirect
 751  * block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks.
 752  * We need to be 1 filesystem block less than the 2^32 sector limit.
 753  */
 754 static loff_t ext2_max_size(int bits)
 755 {
 756         loff_t res = EXT2_NDIR_BLOCKS;
 757         int meta_blocks;
 758         loff_t upper_limit;
 759
 760         /* This is calculated to be the largest file size for a
 761          * dense, file such that the total number of
 762          * sectors in the file, including data and all indirect blocks,
 763          * does not exceed 2^32 -1
 764          * __u32 i_blocks representing the total number of
 765          * 512 bytes blocks of the file
 766          */
 767         upper_limit = (1LL << 32) - 1;
 768
 769         /* total blocks in file system block size */
 770         upper_limit >>= (bits - 9);
 771
 772
 773         /* indirect blocks */
 774         meta_blocks = 1;
 775         /* double indirect blocks */
 776         meta_blocks += 1 + (1LL << (bits-2));
 777         /* tripple indirect blocks */
 778         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
 779
 780         upper_limit -= meta_blocks;
 781         upper_limit <<= bits;
 782
 783         res += 1LL << (bits-2);
 784         res += 1LL << (2*(bits-2));
 785         res += 1LL << (3*(bits-2));
 786         res <<= bits;
 787         if (res > upper_limit)
 788                 res = upper_limit;
 789
 790         if (res > MAX_LFS_FILESIZE)
 791                 res = MAX_LFS_FILESIZE;
 792
 793         return res;
 794 }
 795
 796 static unsigned long descriptor_loc(struct super_block *sb,
 797                                     unsigned long logic_sb_block,
 798                                     int nr)
 799 {
 800         struct ext2_sb_info *sbi = EXT2_SB(sb);
 801         unsigned long bg, first_meta_bg;
 802         int has_super = 0;
 803
 804         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
 805
 806         if (!EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_META_BG) ||
 807             nr < first_meta_bg)
 808                 return (logic_sb_block + nr + 1);
 809         bg = sbi->s_desc_per_block * nr;
 810         if (ext2_bg_has_super(sb, bg))
 811                 has_super = 1;
 812
 813         return ext2_group_first_block_no(sb, bg) + has_super;
 814 }
 815
 816 static int ext2_fill_super(struct super_block *sb, void *data, int silent)
 817 {
 818         struct dax_device *dax_dev = fs_dax_get_by_bdev(sb->s_bdev);
 819         struct buffer_head * bh;
 820         struct ext2_sb_info * sbi;
 821         struct ext2_super_block * es;
 822         struct inode *root;
 823         unsigned long block;
 824         unsigned long sb_block = get_sb_block(&data);
 825         unsigned long logic_sb_block;
 826         unsigned long offset = 0;
 827         unsigned long def_mount_opts;
 828         long ret = -EINVAL;
 829         int blocksize = BLOCK_SIZE;
 830         int db_count;
 831         int i, j;
 832         __le32 features;
 833         int err;
 834         struct ext2_mount_options opts;
 835
 836         err = -ENOMEM;
 837         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
 838         if (!sbi)
 839                 goto failed;
 840
 841         sbi->s_blockgroup_lock =
 842                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
 843         if (!sbi->s_blockgroup_lock) {
 844                 kfree(sbi);
 845                 goto failed;
 846         }
 847         sb->s_fs_info = sbi;
 848         sbi->s_sb_block = sb_block;
 849         sbi->s_daxdev = dax_dev;
 850
 851         spin_lock_init(&sbi->s_lock);
 852
 853         /*
 854          * See what the current blocksize for the device is, and
 855          * use that as the blocksize.  Otherwise (or if the blocksize
 856          * is smaller than the default) use the default.
 857          * This is important for devices that have a hardware
 858          * sectorsize that is larger than the default.
 859          */
 860         blocksize = sb_min_blocksize(sb, BLOCK_SIZE);
 861         if (!blocksize) {
 862                 ext2_msg(sb, KERN_ERR, "error: unable to set blocksize");
 863                 goto failed_sbi;
 864         }
 865
 866         /*
 867          * If the superblock doesn't start on a hardware sector boundary,
 868          * calculate the offset.
 869          */
 870         if (blocksize != BLOCK_SIZE) {
 871                 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
 872                 offset = (sb_block*BLOCK_SIZE) % blocksize;
 873         } else {
 874                 logic_sb_block = sb_block;
 875         }
 876
 877         if (!(bh = sb_bread(sb, logic_sb_block))) {
 878                 ext2_msg(sb, KERN_ERR, "error: unable to read superblock");
 879                 goto failed_sbi;
 880         }
 881         /*
 882          * Note: s_es must be initialized as soon as possible because
 883          *       some ext2 macro-instructions depend on its value
 884          */
 885         es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
 886         sbi->s_es = es;
 887         sb->s_magic = le16_to_cpu(es->s_magic);
 888
 889         if (sb->s_magic != EXT2_SUPER_MAGIC)
 890                 goto cantfind_ext2;
 891
 892         /* Set defaults before we parse the mount options */
 893         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
 894         if (def_mount_opts & EXT2_DEFM_DEBUG)
 895                 set_opt(opts.s_mount_opt, DEBUG);
 896         if (def_mount_opts & EXT2_DEFM_BSDGROUPS)
 897                 set_opt(opts.s_mount_opt, GRPID);
 898         if (def_mount_opts & EXT2_DEFM_UID16)
 899                 set_opt(opts.s_mount_opt, NO_UID32);
 900 #ifdef CONFIG_EXT2_FS_XATTR
 901         if (def_mount_opts & EXT2_DEFM_XATTR_USER)
 902                 set_opt(opts.s_mount_opt, XATTR_USER);
 903 #endif
 904 #ifdef CONFIG_EXT2_FS_POSIX_ACL
 905         if (def_mount_opts & EXT2_DEFM_ACL)
 906                 set_opt(opts.s_mount_opt, POSIX_ACL);
 907 #endif
 908
 909         if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_PANIC)
 910                 set_opt(opts.s_mount_opt, ERRORS_PANIC);
 911         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_CONTINUE)
 912                 set_opt(opts.s_mount_opt, ERRORS_CONT);
 913         else
 914                 set_opt(opts.s_mount_opt, ERRORS_RO);
 915
 916         opts.s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
 917         opts.s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
 918
 919         set_opt(opts.s_mount_opt, RESERVATION);
 920
 921         if (!parse_options((char *) data, sb, &opts))
 922                 goto failed_mount;
 923
 924         sbi->s_mount_opt = opts.s_mount_opt;
 925         sbi->s_resuid = opts.s_resuid;
 926         sbi->s_resgid = opts.s_resgid;
 927
 928         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
 929                 ((EXT2_SB(sb)->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ?
 930                  SB_POSIXACL : 0);
 931         sb->s_iflags |= SB_I_CGROUPWB;
 932
 933         if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV &&
 934             (EXT2_HAS_COMPAT_FEATURE(sb, ~0U) ||
 935              EXT2_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
 936              EXT2_HAS_INCOMPAT_FEATURE(sb, ~0U)))
 937                 ext2_msg(sb, KERN_WARNING,
 938                         "warning: feature flags set on rev 0 fs, "
 939                         "running e2fsck is recommended");
 940         /*
 941          * Check feature flags regardless of the revision level, since we
 942          * previously didn't change the revision level when setting the flags,
 943          * so there is a chance incompat flags are set on a rev 0 filesystem.
 944          */
 945         features = EXT2_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP);
 946         if (features) {
 947                 ext2_msg(sb, KERN_ERR,  "error: couldn't mount because of "
 948                        "unsupported optional features (%x)",
 949                         le32_to_cpu(features));
 950                 goto failed_mount;
 951         }
 952         if (!sb_rdonly(sb) && (features = EXT2_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))){
 953                 ext2_msg(sb, KERN_ERR, "error: couldn't mount RDWR because of "
 954                        "unsupported optional features (%x)",
 955                        le32_to_cpu(features));
 956                 goto failed_mount;
 957         }
 958
 959         blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
 960
 961         if (sbi->s_mount_opt & EXT2_MOUNT_DAX) {
 962                 err = bdev_dax_supported(sb, blocksize);
 963                 if (err)
 964                         goto failed_mount;
 965         }
 966
 967         /* If the blocksize doesn't match, re-read the thing.. */
 968         if (sb->s_blocksize != blocksize) {
 969                 brelse(bh);
 970
 971                 if (!sb_set_blocksize(sb, blocksize)) {
 972                         ext2_msg(sb, KERN_ERR,
 973                                 "error: bad blocksize %d", blocksize);
 974                         goto failed_sbi;
 975                 }
 976
 977                 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
 978                 offset = (sb_block*BLOCK_SIZE) % blocksize;
 979                 bh = sb_bread(sb, logic_sb_block);
 980                 if(!bh) {
 981                         ext2_msg(sb, KERN_ERR, "error: couldn't read"
 982                                 "superblock on 2nd try");
 983                         goto failed_sbi;
 984                 }
 985                 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
 986                 sbi->s_es = es;
 987                 if (es->s_magic != cpu_to_le16(EXT2_SUPER_MAGIC)) {
 988                         ext2_msg(sb, KERN_ERR, "error: magic mismatch");
 989                         goto failed_mount;
 990                 }
 991         }
 992
 993         sb->s_maxbytes = ext2_max_size(sb->s_blocksize_bits);
 994         sb->s_max_links = EXT2_LINK_MAX;
 995
 996         if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV) {
 997                 sbi->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE;
 998                 sbi->s_first_ino = EXT2_GOOD_OLD_FIRST_INO;
 999         } else {
1000                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
1001                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
1002                 if ((sbi->s_inode_size < EXT2_GOOD_OLD_INODE_SIZE) ||
1003                     !is_power_of_2(sbi->s_inode_size) ||
1004                     (sbi->s_inode_size > blocksize)) {
1005                         ext2_msg(sb, KERN_ERR,
1006                                 "error: unsupported inode size: %d",
1007                                 sbi->s_inode_size);
1008                         goto failed_mount;
1009                 }
1010         }
1011
1012         sbi->s_frag_size = EXT2_MIN_FRAG_SIZE <<
1013                                    le32_to_cpu(es->s_log_frag_size);
1014         if (sbi->s_frag_size == 0)
1015                 goto cantfind_ext2;
1016         sbi->s_frags_per_block = sb->s_blocksize / sbi->s_frag_size;
1017
1018         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
1019         sbi->s_frags_per_group = le32_to_cpu(es->s_frags_per_group);
1020         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
1021
1022         if (EXT2_INODE_SIZE(sb) == 0)
1023                 goto cantfind_ext2;
1024         sbi->s_inodes_per_block = sb->s_blocksize / EXT2_INODE_SIZE(sb);
1025         if (sbi->s_inodes_per_block == 0 || sbi->s_inodes_per_group == 0)
1026                 goto cantfind_ext2;
1027         sbi->s_itb_per_group = sbi->s_inodes_per_group /
1028                                         sbi->s_inodes_per_block;
1029         sbi->s_desc_per_block = sb->s_blocksize /
1030                                         sizeof (struct ext2_group_desc);
1031         sbi->s_sbh = bh;
1032         sbi->s_mount_state = le16_to_cpu(es->s_state);
1033         sbi->s_addr_per_block_bits =
1034                 ilog2 (EXT2_ADDR_PER_BLOCK(sb));
1035         sbi->s_desc_per_block_bits =
1036                 ilog2 (EXT2_DESC_PER_BLOCK(sb));
1037
1038         if (sb->s_magic != EXT2_SUPER_MAGIC)
1039                 goto cantfind_ext2;
1040
1041         if (sb->s_blocksize != bh->b_size) {
1042                 if (!silent)
1043                         ext2_msg(sb, KERN_ERR, "error: unsupported blocksize");
1044                 goto failed_mount;
1045         }
1046
1047         if (sb->s_blocksize != sbi->s_frag_size) {
1048                 ext2_msg(sb, KERN_ERR,
1049                         "error: fragsize %lu != blocksize %lu"
1050                         "(not supported yet)",
1051                         sbi->s_frag_size, sb->s_blocksize);
1052                 goto failed_mount;
1053         }
1054
1055         if (sbi->s_blocks_per_group > sb->s_blocksize * 8) {
1056                 ext2_msg(sb, KERN_ERR,
1057                         "error: #blocks per group too big: %lu",
1058                         sbi->s_blocks_per_group);
1059                 goto failed_mount;
1060         }
1061         if (sbi->s_frags_per_group > sb->s_blocksize * 8) {
1062                 ext2_msg(sb, KERN_ERR,
1063                         "error: #fragments per group too big: %lu",
1064                         sbi->s_frags_per_group);
1065                 goto failed_mount;
1066         }
1067         if (sbi->s_inodes_per_group > sb->s_blocksize * 8) {
1068                 ext2_msg(sb, KERN_ERR,
1069                         "error: #inodes per group too big: %lu",
1070                         sbi->s_inodes_per_group);
1071                 goto failed_mount;
1072         }
1073
1074         if (EXT2_BLOCKS_PER_GROUP(sb) == 0)
1075                 goto cantfind_ext2;
1076         sbi->s_groups_count = ((le32_to_cpu(es->s_blocks_count) -
1077                                 le32_to_cpu(es->s_first_data_block) - 1)
1078                                         / EXT2_BLOCKS_PER_GROUP(sb)) + 1;
1079         db_count = (sbi->s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) /
1080                    EXT2_DESC_PER_BLOCK(sb);
1081         sbi->s_group_desc = kmalloc (db_count * sizeof (struct buffer_head *), GFP_KERNEL);
1082         if (sbi->s_group_desc == NULL) {
1083                 ext2_msg(sb, KERN_ERR, "error: not enough memory");
1084                 goto failed_mount;
1085         }
1086         bgl_lock_init(sbi->s_blockgroup_lock);
1087         sbi->s_debts = kcalloc(sbi->s_groups_count, sizeof(*sbi->s_debts), GFP_KERNEL);
1088         if (!sbi->s_debts) {
1089                 ext2_msg(sb, KERN_ERR, "error: not enough memory");
1090                 goto failed_mount_group_desc;
1091         }
1092         for (i = 0; i < db_count; i++) {
1093                 block = descriptor_loc(sb, logic_sb_block, i);
1094                 sbi->s_group_desc[i] = sb_bread(sb, block);
1095                 if (!sbi->s_group_desc[i]) {
1096                         for (j = 0; j < i; j++)
1097                                 brelse (sbi->s_group_desc[j]);
1098                         ext2_msg(sb, KERN_ERR,
1099                                 "error: unable to read group descriptors");
1100                         goto failed_mount_group_desc;
1101                 }
1102         }
1103         if (!ext2_check_descriptors (sb)) {
1104                 ext2_msg(sb, KERN_ERR, "group descriptors corrupted");
1105                 goto failed_mount2;
1106         }
1107         sbi->s_gdb_count = db_count;
1108         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
1109         spin_lock_init(&sbi->s_next_gen_lock);
1110
1111         /* per fileystem reservation list head & lock */
1112         spin_lock_init(&sbi->s_rsv_window_lock);
1113         sbi->s_rsv_window_root = RB_ROOT;
1114         /*
1115          * Add a single, static dummy reservation to the start of the
1116          * reservation window list --- it gives us a placeholder for
1117          * append-at-start-of-list which makes the allocation logic
1118          * _much_ simpler.
1119          */
1120         sbi->s_rsv_window_head.rsv_start = EXT2_RESERVE_WINDOW_NOT_ALLOCATED;
1121         sbi->s_rsv_window_head.rsv_end = EXT2_RESERVE_WINDOW_NOT_ALLOCATED;
1122         sbi->s_rsv_window_head.rsv_alloc_hit = 0;
1123         sbi->s_rsv_window_head.rsv_goal_size = 0;
1124         ext2_rsv_window_add(sb, &sbi->s_rsv_window_head);
1125
1126         err = percpu_counter_init(&sbi->s_freeblocks_counter,
1127                                 ext2_count_free_blocks(sb), GFP_KERNEL);
1128         if (!err) {
1129                 err = percpu_counter_init(&sbi->s_freeinodes_counter,
1130                                 ext2_count_free_inodes(sb), GFP_KERNEL);
1131         }
1132         if (!err) {
1133                 err = percpu_counter_init(&sbi->s_dirs_counter,
1134                                 ext2_count_dirs(sb), GFP_KERNEL);
1135         }
1136         if (err) {
1137                 ext2_msg(sb, KERN_ERR, "error: insufficient memory");
1138                 goto failed_mount3;
1139         }
1140
1141 #ifdef CONFIG_EXT2_FS_XATTR
1142         sbi->s_ea_block_cache = ext2_xattr_create_cache();
1143         if (!sbi->s_ea_block_cache) {
1144                 ext2_msg(sb, KERN_ERR, "Failed to create ea_block_cache");
1145                 goto failed_mount3;
1146         }
1147 #endif
1148         /*
1149          * set up enough so that it can read an inode
1150          */
1151         sb->s_op = &ext2_sops;
1152         sb->s_export_op = &ext2_export_ops;
1153         sb->s_xattr = ext2_xattr_handlers;
1154
1155 #ifdef CONFIG_QUOTA
1156         sb->dq_op = &dquot_operations;
1157         sb->s_qcop = &ext2_quotactl_ops;
1158         sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP;
1159 #endif
1160
1161         root = ext2_iget(sb, EXT2_ROOT_INO);
1162         if (IS_ERR(root)) {
1163                 ret = PTR_ERR(root);
1164                 goto failed_mount3;
1165         }
1166         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
1167                 iput(root);
1168                 ext2_msg(sb, KERN_ERR, "error: corrupt root inode, run e2fsck");
1169                 goto failed_mount3;
1170         }
1171
1172         sb->s_root = d_make_root(root);
1173         if (!sb->s_root) {
1174                 ext2_msg(sb, KERN_ERR, "error: get root inode failed");
1175                 ret = -ENOMEM;
1176                 goto failed_mount3;
1177         }
1178         if (EXT2_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_HAS_JOURNAL))
1179                 ext2_msg(sb, KERN_WARNING,
1180                         "warning: mounting ext3 filesystem as ext2");
1181         if (ext2_setup_super (sb, es, sb_rdonly(sb)))
1182                 sb->s_flags |= SB_RDONLY;
1183         ext2_write_super(sb);
1184         return 0;
1185
1186 cantfind_ext2:
1187         if (!silent)
1188                 ext2_msg(sb, KERN_ERR,
1189                         "error: can't find an ext2 filesystem on dev %s.",
1190                         sb->s_id);
1191         goto failed_mount;
1192 failed_mount3:
1193         if (sbi->s_ea_block_cache)
1194                 ext2_xattr_destroy_cache(sbi->s_ea_block_cache);
1195         percpu_counter_destroy(&sbi->s_freeblocks_counter);
1196         percpu_counter_destroy(&sbi->s_freeinodes_counter);
1197         percpu_counter_destroy(&sbi->s_dirs_counter);
1198 failed_mount2:
1199         for (i = 0; i < db_count; i++)
1200                 brelse(sbi->s_group_desc[i]);
1201 failed_mount_group_desc:
1202         kfree(sbi->s_group_desc);
1203         kfree(sbi->s_debts);
1204 failed_mount:
1205         brelse(bh);
1206 failed_sbi:
1207         sb->s_fs_info = NULL;
1208         kfree(sbi->s_blockgroup_lock);
1209         kfree(sbi);
1210 failed:
1211         fs_put_dax(dax_dev);
1212         return ret;
1213 }
1214
1215 static void ext2_clear_super_error(struct super_block *sb)
1216 {
1217         struct buffer_head *sbh = EXT2_SB(sb)->s_sbh;
1218
1219         if (buffer_write_io_error(sbh)) {
1220                 /*
1221                  * Oh, dear.  A previous attempt to write the
1222                  * superblock failed.  This could happen because the
1223                  * USB device was yanked out.  Or it could happen to
1224                  * be a transient write error and maybe the block will
1225                  * be remapped.  Nothing we can do but to retry the
1226                  * write and hope for the best.
1227                  */
1228                 ext2_msg(sb, KERN_ERR,
1229                        "previous I/O error to superblock detected\n");
1230                 clear_buffer_write_io_error(sbh);
1231                 set_buffer_uptodate(sbh);
1232         }
1233 }
1234
1235 void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es,
1236                      int wait)
1237 {
1238         ext2_clear_super_error(sb);
1239         spin_lock(&EXT2_SB(sb)->s_lock);
1240         es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb));
1241         es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb));
1242         es->s_wtime = cpu_to_le32(get_seconds());
1243         /* unlock before we do IO */
1244         spin_unlock(&EXT2_SB(sb)->s_lock);
1245         mark_buffer_dirty(EXT2_SB(sb)->s_sbh);
1246         if (wait)
1247                 sync_dirty_buffer(EXT2_SB(sb)->s_sbh);
1248 }
1249
1250 /*
1251  * In the second extended file system, it is not necessary to
1252  * write the super block since we use a mapping of the
1253  * disk super block in a buffer.
1254  *
1255  * However, this function is still used to set the fs valid
1256  * flags to 0.  We need to set this flag to 0 since the fs
1257  * may have been checked while mounted and e2fsck may have
1258  * set s_state to EXT2_VALID_FS after some corrections.
1259  */
1260 static int ext2_sync_fs(struct super_block *sb, int wait)
1261 {
1262         struct ext2_sb_info *sbi = EXT2_SB(sb);
1263         struct ext2_super_block *es = EXT2_SB(sb)->s_es;
1264
1265         /*
1266          * Write quota structures to quota file, sync_blockdev() will write
1267          * them to disk later
1268          */
1269         dquot_writeback_dquots(sb, -1);
1270
1271         spin_lock(&sbi->s_lock);
1272         if (es->s_state & cpu_to_le16(EXT2_VALID_FS)) {
1273                 ext2_debug("setting valid to 0\n");
1274                 es->s_state &= cpu_to_le16(~EXT2_VALID_FS);
1275         }
1276         spin_unlock(&sbi->s_lock);
1277         ext2_sync_super(sb, es, wait);
1278         return 0;
1279 }
1280
1281 static int ext2_freeze(struct super_block *sb)
1282 {
1283         struct ext2_sb_info *sbi = EXT2_SB(sb);
1284
1285         /*
1286          * Open but unlinked files present? Keep EXT2_VALID_FS flag cleared
1287          * because we have unattached inodes and thus filesystem is not fully
1288          * consistent.
1289          */
1290         if (atomic_long_read(&sb->s_remove_count)) {
1291                 ext2_sync_fs(sb, 1);
1292                 return 0;
1293         }
1294         /* Set EXT2_FS_VALID flag */
1295         spin_lock(&sbi->s_lock);
1296         sbi->s_es->s_state = cpu_to_le16(sbi->s_mount_state);
1297         spin_unlock(&sbi->s_lock);
1298         ext2_sync_super(sb, sbi->s_es, 1);
1299
1300         return 0;
1301 }
1302
1303 static int ext2_unfreeze(struct super_block *sb)
1304 {
1305         /* Just write sb to clear EXT2_VALID_FS flag */
1306         ext2_write_super(sb);
1307
1308         return 0;
1309 }
1310
1311 static void ext2_write_super(struct super_block *sb)
1312 {
1313         if (!sb_rdonly(sb))
1314                 ext2_sync_fs(sb, 1);
1315 }
1316
1317 static int ext2_remount (struct super_block * sb, int * flags, char * data)
1318 {
1319         struct ext2_sb_info * sbi = EXT2_SB(sb);
1320         struct ext2_super_block * es;
1321         struct ext2_mount_options new_opts;
1322         int err;
1323
1324         sync_filesystem(sb);
1325
1326         spin_lock(&sbi->s_lock);
1327         new_opts.s_mount_opt = sbi->s_mount_opt;
1328         new_opts.s_resuid = sbi->s_resuid;
1329         new_opts.s_resgid = sbi->s_resgid;
1330         spin_unlock(&sbi->s_lock);
1331
1332         /*
1333          * Allow the "check" option to be passed as a remount option.
1334          */
1335         if (!parse_options(data, sb, &new_opts))
1336                 return -EINVAL;
1337
1338         spin_lock(&sbi->s_lock);
1339         es = sbi->s_es;
1340         if ((sbi->s_mount_opt ^ new_opts.s_mount_opt) & EXT2_MOUNT_DAX) {
1341                 ext2_msg(sb, KERN_WARNING, "warning: refusing change of "
1342                          "dax flag with busy inodes while remounting");
1343                 new_opts.s_mount_opt ^= EXT2_MOUNT_DAX;
1344         }
1345         if ((bool)(*flags & SB_RDONLY) == sb_rdonly(sb))
1346                 goto out_set;
1347         if (*flags & SB_RDONLY) {
1348                 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS ||
1349                     !(sbi->s_mount_state & EXT2_VALID_FS))
1350                         goto out_set;
1351
1352                 /*
1353                  * OK, we are remounting a valid rw partition rdonly, so set
1354                  * the rdonly flag and then mark the partition as valid again.
1355                  */
1356                 es->s_state = cpu_to_le16(sbi->s_mount_state);
1357                 es->s_mtime = cpu_to_le32(get_seconds());
1358                 spin_unlock(&sbi->s_lock);
1359
1360                 err = dquot_suspend(sb, -1);
1361                 if (err < 0)
1362                         return err;
1363
1364                 ext2_sync_super(sb, es, 1);
1365         } else {
1366                 __le32 ret = EXT2_HAS_RO_COMPAT_FEATURE(sb,
1367                                                ~EXT2_FEATURE_RO_COMPAT_SUPP);
1368                 if (ret) {
1369                         spin_unlock(&sbi->s_lock);
1370                         ext2_msg(sb, KERN_WARNING,
1371                                 "warning: couldn't remount RDWR because of "
1372                                 "unsupported optional features (%x).",
1373                                 le32_to_cpu(ret));
1374                         return -EROFS;
1375                 }
1376                 /*
1377                  * Mounting a RDONLY partition read-write, so reread and
1378                  * store the current valid flag.  (It may have been changed
1379                  * by e2fsck since we originally mounted the partition.)
1380                  */
1381                 sbi->s_mount_state = le16_to_cpu(es->s_state);
1382                 if (!ext2_setup_super (sb, es, 0))
1383                         sb->s_flags &= ~SB_RDONLY;
1384                 spin_unlock(&sbi->s_lock);
1385
1386                 ext2_write_super(sb);
1387
1388                 dquot_resume(sb, -1);
1389         }
1390
1391         spin_lock(&sbi->s_lock);
1392 out_set:
1393         sbi->s_mount_opt = new_opts.s_mount_opt;
1394         sbi->s_resuid = new_opts.s_resuid;
1395         sbi->s_resgid = new_opts.s_resgid;
1396         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
1397                 ((sbi->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ? SB_POSIXACL : 0);
1398         spin_unlock(&sbi->s_lock);
1399
1400         return 0;
1401 }
1402
1403 static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf)
1404 {
1405         struct super_block *sb = dentry->d_sb;
1406         struct ext2_sb_info *sbi = EXT2_SB(sb);
1407         struct ext2_super_block *es = sbi->s_es;
1408         u64 fsid;
1409
1410         spin_lock(&sbi->s_lock);
1411
1412         if (test_opt (sb, MINIX_DF))
1413                 sbi->s_overhead_last = 0;
1414         else if (sbi->s_blocks_last != le32_to_cpu(es->s_blocks_count)) {
1415                 unsigned long i, overhead = 0;
1416                 smp_rmb();
1417
1418                 /*
1419                  * Compute the overhead (FS structures). This is constant
1420                  * for a given filesystem unless the number of block groups
1421                  * changes so we cache the previous value until it does.
1422                  */
1423
1424                 /*
1425                  * All of the blocks before first_data_block are
1426                  * overhead
1427                  */
1428                 overhead = le32_to_cpu(es->s_first_data_block);
1429
1430                 /*
1431                  * Add the overhead attributed to the superblock and
1432                  * block group descriptors.  If the sparse superblocks
1433                  * feature is turned on, then not all groups have this.
1434                  */
1435                 for (i = 0; i < sbi->s_groups_count; i++)
1436                         overhead += ext2_bg_has_super(sb, i) +
1437                                 ext2_bg_num_gdb(sb, i);
1438
1439                 /*
1440                  * Every block group has an inode bitmap, a block
1441                  * bitmap, and an inode table.
1442                  */
1443                 overhead += (sbi->s_groups_count *
1444                              (2 + sbi->s_itb_per_group));
1445                 sbi->s_overhead_last = overhead;
1446                 smp_wmb();
1447                 sbi->s_blocks_last = le32_to_cpu(es->s_blocks_count);
1448         }
1449
1450         buf->f_type = EXT2_SUPER_MAGIC;
1451         buf->f_bsize = sb->s_blocksize;
1452         buf->f_blocks = le32_to_cpu(es->s_blocks_count) - sbi->s_overhead_last;
1453         buf->f_bfree = ext2_count_free_blocks(sb);
1454         es->s_free_blocks_count = cpu_to_le32(buf->f_bfree);
1455         buf->f_bavail = buf->f_bfree - le32_to_cpu(es->s_r_blocks_count);
1456         if (buf->f_bfree < le32_to_cpu(es->s_r_blocks_count))
1457                 buf->f_bavail = 0;
1458         buf->f_files = le32_to_cpu(es->s_inodes_count);
1459         buf->f_ffree = ext2_count_free_inodes(sb);
1460         es->s_free_inodes_count = cpu_to_le32(buf->f_ffree);
1461         buf->f_namelen = EXT2_NAME_LEN;
1462         fsid = le64_to_cpup((void *)es->s_uuid) ^
1463                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
1464         buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
1465         buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
1466         spin_unlock(&sbi->s_lock);
1467         return 0;
1468 }
1469
1470 static struct dentry *ext2_mount(struct file_system_type *fs_type,
1471         int flags, const char *dev_name, void *data)
1472 {
1473         return mount_bdev(fs_type, flags, dev_name, data, ext2_fill_super);
1474 }
1475
1476 #ifdef CONFIG_QUOTA
1477
1478 /* Read data from quotafile - avoid pagecache and such because we cannot afford
1479  * acquiring the locks... As quota files are never truncated and quota code
1480  * itself serializes the operations (and no one else should touch the files)
1481  * we don't have to be afraid of races */
1482 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data,
1483                                size_t len, loff_t off)
1484 {
1485         struct inode *inode = sb_dqopt(sb)->files[type];
1486         sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb);
1487         int err = 0;
1488         int offset = off & (sb->s_blocksize - 1);
1489         int tocopy;
1490         size_t toread;
1491         struct buffer_head tmp_bh;
1492         struct buffer_head *bh;
1493         loff_t i_size = i_size_read(inode);
1494
1495         if (off > i_size)
1496                 return 0;
1497         if (off+len > i_size)
1498                 len = i_size-off;
1499         toread = len;
1500         while (toread > 0) {
1501                 tocopy = sb->s_blocksize - offset < toread ?
1502                                 sb->s_blocksize - offset : toread;
1503
1504                 tmp_bh.b_state = 0;
1505                 tmp_bh.b_size = sb->s_blocksize;
1506                 err = ext2_get_block(inode, blk, &tmp_bh, 0);
1507                 if (err < 0)
1508                         return err;
1509                 if (!buffer_mapped(&tmp_bh))    /* A hole? */
1510                         memset(data, 0, tocopy);
1511                 else {
1512                         bh = sb_bread(sb, tmp_bh.b_blocknr);
1513                         if (!bh)
1514                                 return -EIO;
1515                         memcpy(data, bh->b_data+offset, tocopy);
1516                         brelse(bh);
1517                 }
1518                 offset = 0;
1519                 toread -= tocopy;
1520                 data += tocopy;
1521                 blk++;
1522         }
1523         return len;
1524 }
1525
1526 /* Write to quotafile */
1527 static ssize_t ext2_quota_write(struct super_block *sb, int type,
1528                                 const char *data, size_t len, loff_t off)
1529 {
1530         struct inode *inode = sb_dqopt(sb)->files[type];
1531         sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb);
1532         int err = 0;
1533         int offset = off & (sb->s_blocksize - 1);
1534         int tocopy;
1535         size_t towrite = len;
1536         struct buffer_head tmp_bh;
1537         struct buffer_head *bh;
1538
1539         while (towrite > 0) {
1540                 tocopy = sb->s_blocksize - offset < towrite ?
1541                                 sb->s_blocksize - offset : towrite;
1542
1543                 tmp_bh.b_state = 0;
1544                 tmp_bh.b_size = sb->s_blocksize;
1545                 err = ext2_get_block(inode, blk, &tmp_bh, 1);
1546                 if (err < 0)
1547                         goto out;
1548                 if (offset || tocopy != EXT2_BLOCK_SIZE(sb))
1549                         bh = sb_bread(sb, tmp_bh.b_blocknr);
1550                 else
1551                         bh = sb_getblk(sb, tmp_bh.b_blocknr);
1552                 if (unlikely(!bh)) {
1553                         err = -EIO;
1554                         goto out;
1555                 }
1556                 lock_buffer(bh);
1557                 memcpy(bh->b_data+offset, data, tocopy);
1558                 flush_dcache_page(bh->b_page);
1559                 set_buffer_uptodate(bh);
1560                 mark_buffer_dirty(bh);
1561                 unlock_buffer(bh);
1562                 brelse(bh);
1563                 offset = 0;
1564                 towrite -= tocopy;
1565                 data += tocopy;
1566                 blk++;
1567         }
1568 out:
1569         if (len == towrite)
1570                 return err;
1571         if (inode->i_size < off+len-towrite)
1572                 i_size_write(inode, off+len-towrite);
1573         inode_inc_iversion(inode);
1574         inode->i_mtime = inode->i_ctime = current_time(inode);
1575         mark_inode_dirty(inode);
1576         return len - towrite;
1577 }
1578
1579 static int ext2_quota_on(struct super_block *sb, int type, int format_id,
1580                          const struct path *path)
1581 {
1582         int err;
1583         struct inode *inode;
1584
1585         err = dquot_quota_on(sb, type, format_id, path);
1586         if (err)
1587                 return err;
1588
1589         inode = d_inode(path->dentry);
1590         inode_lock(inode);
1591         EXT2_I(inode)->i_flags |= EXT2_NOATIME_FL | EXT2_IMMUTABLE_FL;
1592         inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,
1593                         S_NOATIME | S_IMMUTABLE);
1594         inode_unlock(inode);
1595         mark_inode_dirty(inode);
1596
1597         return 0;
1598 }
1599
1600 static int ext2_quota_off(struct super_block *sb, int type)
1601 {
1602         struct inode *inode = sb_dqopt(sb)->files[type];
1603         int err;
1604
1605         if (!inode || !igrab(inode))
1606                 goto out;
1607
1608         err = dquot_quota_off(sb, type);
1609         if (err)
1610                 goto out_put;
1611
1612         inode_lock(inode);
1613         EXT2_I(inode)->i_flags &= ~(EXT2_NOATIME_FL | EXT2_IMMUTABLE_FL);
1614         inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
1615         inode_unlock(inode);
1616         mark_inode_dirty(inode);
1617 out_put:
1618         iput(inode);
1619         return err;
1620 out:
1621         return dquot_quota_off(sb, type);
1622 }
1623
1624 #endif
1625
1626 static struct file_system_type ext2_fs_type = {
1627         .owner          = THIS_MODULE,
1628         .name           = "ext2",
1629         .mount          = ext2_mount,
1630         .kill_sb        = kill_block_super,
1631         .fs_flags       = FS_REQUIRES_DEV,
1632 };
1633 MODULE_ALIAS_FS("ext2");
1634
1635 static int __init init_ext2_fs(void)
1636 {
1637         int err;
1638
1639         err = init_inodecache();
1640         if (err)
1641                 return err;
1642         err = register_filesystem(&ext2_fs_type);
1643         if (err)
1644                 goto out;
1645         return 0;
1646 out:
1647         destroy_inodecache();
1648         return err;
1649 }
1650
1651 static void __exit exit_ext2_fs(void)
1652 {
1653         unregister_filesystem(&ext2_fs_type);
1654         destroy_inodecache();
1655 }
1656
1657 MODULE_AUTHOR("Remy Card and others");
1658 MODULE_DESCRIPTION("Second Extended Filesystem");
1659 MODULE_LICENSE("GPL");
1660 module_init(init_ext2_fs)
1661 module_exit(exit_ext2_fs)