1663 lines · c
1// SPDX-License-Identifier: GPL-2.0-only2/*3 * linux/fs/ext2/super.c4 *5 * Copyright (C) 1992, 1993, 1994, 19956 * Remy Card (card@masi.ibp.fr)7 * Laboratoire MASI - Institut Blaise Pascal8 * Universite Pierre et Marie Curie (Paris VI)9 *10 * from11 *12 * linux/fs/minix/inode.c13 *14 * Copyright (C) 1991, 1992 Linus Torvalds15 *16 * Big-endian to little-endian byte-swapping/bitmaps by17 * David S. Miller (davem@caip.rutgers.edu), 199518 */19 20#include <linux/module.h>21#include <linux/string.h>22#include <linux/fs.h>23#include <linux/slab.h>24#include <linux/init.h>25#include <linux/blkdev.h>26#include <linux/parser.h>27#include <linux/random.h>28#include <linux/buffer_head.h>29#include <linux/exportfs.h>30#include <linux/vfs.h>31#include <linux/seq_file.h>32#include <linux/mount.h>33#include <linux/log2.h>34#include <linux/quotaops.h>35#include <linux/uaccess.h>36#include <linux/dax.h>37#include <linux/iversion.h>38#include "ext2.h"39#include "xattr.h"40#include "acl.h"41 42static void ext2_write_super(struct super_block *sb);43static int ext2_remount (struct super_block * sb, int * flags, char * data);44static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf);45static int ext2_sync_fs(struct super_block *sb, int wait);46static int ext2_freeze(struct super_block *sb);47static int ext2_unfreeze(struct super_block *sb);48 49void ext2_error(struct super_block *sb, const char *function,50 const char *fmt, ...)51{52 struct va_format vaf;53 va_list args;54 struct ext2_sb_info *sbi = EXT2_SB(sb);55 struct ext2_super_block *es = sbi->s_es;56 57 if (!sb_rdonly(sb)) {58 spin_lock(&sbi->s_lock);59 sbi->s_mount_state |= EXT2_ERROR_FS;60 es->s_state |= cpu_to_le16(EXT2_ERROR_FS);61 spin_unlock(&sbi->s_lock);62 ext2_sync_super(sb, es, 1);63 }64 65 va_start(args, fmt);66 67 vaf.fmt = fmt;68 vaf.va = &args;69 70 printk(KERN_CRIT "EXT2-fs (%s): error: %s: %pV\n",71 sb->s_id, function, &vaf);72 73 va_end(args);74 75 if (test_opt(sb, ERRORS_PANIC))76 panic("EXT2-fs: panic from previous error\n");77 if (!sb_rdonly(sb) && test_opt(sb, ERRORS_RO)) {78 ext2_msg(sb, KERN_CRIT,79 "error: remounting filesystem read-only");80 sb->s_flags |= SB_RDONLY;81 }82}83 84void ext2_msg(struct super_block *sb, const char *prefix,85 const char *fmt, ...)86{87 struct va_format vaf;88 va_list args;89 90 va_start(args, fmt);91 92 vaf.fmt = fmt;93 vaf.va = &args;94 95 printk("%sEXT2-fs (%s): %pV\n", prefix, sb->s_id, &vaf);96 97 va_end(args);98}99 100/*101 * This must be called with sbi->s_lock held.102 */103void ext2_update_dynamic_rev(struct super_block *sb)104{105 struct ext2_super_block *es = EXT2_SB(sb)->s_es;106 107 if (le32_to_cpu(es->s_rev_level) > EXT2_GOOD_OLD_REV)108 return;109 110 ext2_msg(sb, KERN_WARNING,111 "warning: updating to rev %d because of "112 "new feature flag, running e2fsck is recommended",113 EXT2_DYNAMIC_REV);114 115 es->s_first_ino = cpu_to_le32(EXT2_GOOD_OLD_FIRST_INO);116 es->s_inode_size = cpu_to_le16(EXT2_GOOD_OLD_INODE_SIZE);117 es->s_rev_level = cpu_to_le32(EXT2_DYNAMIC_REV);118 /* leave es->s_feature_*compat flags alone */119 /* es->s_uuid will be set by e2fsck if empty */120 121 /*122 * The rest of the superblock fields should be zero, and if not it123 * means they are likely already in use, so leave them alone. We124 * can leave it up to e2fsck to clean up any inconsistencies there.125 */126}127 128#ifdef CONFIG_QUOTA129static int ext2_quota_off(struct super_block *sb, int type);130 131static void ext2_quota_off_umount(struct super_block *sb)132{133 int type;134 135 for (type = 0; type < MAXQUOTAS; type++)136 ext2_quota_off(sb, type);137}138#else139static inline void ext2_quota_off_umount(struct super_block *sb)140{141}142#endif143 144static void ext2_put_super (struct super_block * sb)145{146 int db_count;147 int i;148 struct ext2_sb_info *sbi = EXT2_SB(sb);149 150 ext2_quota_off_umount(sb);151 152 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 brelse(sbi->s_group_desc[i]);166 kvfree(sbi->s_group_desc);167 kfree(sbi->s_debts);168 percpu_counter_destroy(&sbi->s_freeblocks_counter);169 percpu_counter_destroy(&sbi->s_freeinodes_counter);170 percpu_counter_destroy(&sbi->s_dirs_counter);171 brelse (sbi->s_sbh);172 sb->s_fs_info = NULL;173 kfree(sbi->s_blockgroup_lock);174 fs_put_dax(sbi->s_daxdev, NULL);175 kfree(sbi);176}177 178static struct kmem_cache * ext2_inode_cachep;179 180static struct inode *ext2_alloc_inode(struct super_block *sb)181{182 struct ext2_inode_info *ei;183 ei = alloc_inode_sb(sb, ext2_inode_cachep, GFP_KERNEL);184 if (!ei)185 return NULL;186 ei->i_block_alloc_info = NULL;187 inode_set_iversion(&ei->vfs_inode, 1);188#ifdef CONFIG_QUOTA189 memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));190#endif191 192 return &ei->vfs_inode;193}194 195static void ext2_free_in_core_inode(struct inode *inode)196{197 kmem_cache_free(ext2_inode_cachep, EXT2_I(inode));198}199 200static void init_once(void *foo)201{202 struct ext2_inode_info *ei = (struct ext2_inode_info *) foo;203 204 rwlock_init(&ei->i_meta_lock);205#ifdef CONFIG_EXT2_FS_XATTR206 init_rwsem(&ei->xattr_sem);207#endif208 mutex_init(&ei->truncate_mutex);209 inode_init_once(&ei->vfs_inode);210}211 212static int __init init_inodecache(void)213{214 ext2_inode_cachep = kmem_cache_create_usercopy("ext2_inode_cache",215 sizeof(struct ext2_inode_info), 0,216 SLAB_RECLAIM_ACCOUNT | SLAB_ACCOUNT,217 offsetof(struct ext2_inode_info, i_data),218 sizeof_field(struct ext2_inode_info, i_data),219 init_once);220 if (ext2_inode_cachep == NULL)221 return -ENOMEM;222 return 0;223}224 225static void destroy_inodecache(void)226{227 /*228 * Make sure all delayed rcu free inodes are flushed before we229 * destroy cache.230 */231 rcu_barrier();232 kmem_cache_destroy(ext2_inode_cachep);233}234 235static int ext2_show_options(struct seq_file *seq, struct dentry *root)236{237 struct super_block *sb = root->d_sb;238 struct ext2_sb_info *sbi = EXT2_SB(sb);239 struct ext2_super_block *es = sbi->s_es;240 unsigned long def_mount_opts;241 242 spin_lock(&sbi->s_lock);243 def_mount_opts = le32_to_cpu(es->s_default_mount_opts);244 245 if (sbi->s_sb_block != 1)246 seq_printf(seq, ",sb=%lu", sbi->s_sb_block);247 if (test_opt(sb, MINIX_DF))248 seq_puts(seq, ",minixdf");249 if (test_opt(sb, GRPID))250 seq_puts(seq, ",grpid");251 if (!test_opt(sb, GRPID) && (def_mount_opts & EXT2_DEFM_BSDGROUPS))252 seq_puts(seq, ",nogrpid");253 if (!uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT2_DEF_RESUID)) ||254 le16_to_cpu(es->s_def_resuid) != EXT2_DEF_RESUID) {255 seq_printf(seq, ",resuid=%u",256 from_kuid_munged(&init_user_ns, sbi->s_resuid));257 }258 if (!gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT2_DEF_RESGID)) ||259 le16_to_cpu(es->s_def_resgid) != EXT2_DEF_RESGID) {260 seq_printf(seq, ",resgid=%u",261 from_kgid_munged(&init_user_ns, sbi->s_resgid));262 }263 if (test_opt(sb, ERRORS_RO)) {264 int def_errors = le16_to_cpu(es->s_errors);265 266 if (def_errors == EXT2_ERRORS_PANIC ||267 def_errors == EXT2_ERRORS_CONTINUE) {268 seq_puts(seq, ",errors=remount-ro");269 }270 }271 if (test_opt(sb, ERRORS_CONT))272 seq_puts(seq, ",errors=continue");273 if (test_opt(sb, ERRORS_PANIC))274 seq_puts(seq, ",errors=panic");275 if (test_opt(sb, NO_UID32))276 seq_puts(seq, ",nouid32");277 if (test_opt(sb, DEBUG))278 seq_puts(seq, ",debug");279 if (test_opt(sb, OLDALLOC))280 seq_puts(seq, ",oldalloc");281 282#ifdef CONFIG_EXT2_FS_XATTR283 if (test_opt(sb, XATTR_USER))284 seq_puts(seq, ",user_xattr");285 if (!test_opt(sb, XATTR_USER) &&286 (def_mount_opts & EXT2_DEFM_XATTR_USER)) {287 seq_puts(seq, ",nouser_xattr");288 }289#endif290 291#ifdef CONFIG_EXT2_FS_POSIX_ACL292 if (test_opt(sb, POSIX_ACL))293 seq_puts(seq, ",acl");294 if (!test_opt(sb, POSIX_ACL) && (def_mount_opts & EXT2_DEFM_ACL))295 seq_puts(seq, ",noacl");296#endif297 298 if (test_opt(sb, USRQUOTA))299 seq_puts(seq, ",usrquota");300 301 if (test_opt(sb, GRPQUOTA))302 seq_puts(seq, ",grpquota");303 304 if (test_opt(sb, XIP))305 seq_puts(seq, ",xip");306 307 if (test_opt(sb, DAX))308 seq_puts(seq, ",dax");309 310 if (!test_opt(sb, RESERVATION))311 seq_puts(seq, ",noreservation");312 313 spin_unlock(&sbi->s_lock);314 return 0;315}316 317#ifdef CONFIG_QUOTA318static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, size_t len, loff_t off);319static ssize_t ext2_quota_write(struct super_block *sb, int type, const char *data, size_t len, loff_t off);320static int ext2_quota_on(struct super_block *sb, int type, int format_id,321 const struct path *path);322static struct dquot __rcu **ext2_get_dquots(struct inode *inode)323{324 return EXT2_I(inode)->i_dquot;325}326 327static const struct quotactl_ops ext2_quotactl_ops = {328 .quota_on = ext2_quota_on,329 .quota_off = ext2_quota_off,330 .quota_sync = dquot_quota_sync,331 .get_state = dquot_get_state,332 .set_info = dquot_set_dqinfo,333 .get_dqblk = dquot_get_dqblk,334 .set_dqblk = dquot_set_dqblk,335 .get_nextdqblk = dquot_get_next_dqblk,336};337#endif338 339static const struct super_operations ext2_sops = {340 .alloc_inode = ext2_alloc_inode,341 .free_inode = ext2_free_in_core_inode,342 .write_inode = ext2_write_inode,343 .evict_inode = ext2_evict_inode,344 .put_super = ext2_put_super,345 .sync_fs = ext2_sync_fs,346 .freeze_fs = ext2_freeze,347 .unfreeze_fs = ext2_unfreeze,348 .statfs = ext2_statfs,349 .remount_fs = ext2_remount,350 .show_options = ext2_show_options,351#ifdef CONFIG_QUOTA352 .quota_read = ext2_quota_read,353 .quota_write = ext2_quota_write,354 .get_dquots = ext2_get_dquots,355#endif356};357 358static struct inode *ext2_nfs_get_inode(struct super_block *sb,359 u64 ino, u32 generation)360{361 struct inode *inode;362 363 if (ino < EXT2_FIRST_INO(sb) && ino != EXT2_ROOT_INO)364 return ERR_PTR(-ESTALE);365 if (ino > le32_to_cpu(EXT2_SB(sb)->s_es->s_inodes_count))366 return ERR_PTR(-ESTALE);367 368 /*369 * ext2_iget isn't quite right if the inode is currently unallocated!370 * However ext2_iget currently does appropriate checks to handle stale371 * inodes so everything is OK.372 */373 inode = ext2_iget(sb, ino);374 if (IS_ERR(inode))375 return ERR_CAST(inode);376 if (generation && inode->i_generation != generation) {377 /* we didn't find the right inode.. */378 iput(inode);379 return ERR_PTR(-ESTALE);380 }381 return inode;382}383 384static struct dentry *ext2_fh_to_dentry(struct super_block *sb, struct fid *fid,385 int fh_len, int fh_type)386{387 return generic_fh_to_dentry(sb, fid, fh_len, fh_type,388 ext2_nfs_get_inode);389}390 391static struct dentry *ext2_fh_to_parent(struct super_block *sb, struct fid *fid,392 int fh_len, int fh_type)393{394 return generic_fh_to_parent(sb, fid, fh_len, fh_type,395 ext2_nfs_get_inode);396}397 398static const struct export_operations ext2_export_ops = {399 .encode_fh = generic_encode_ino32_fh,400 .fh_to_dentry = ext2_fh_to_dentry,401 .fh_to_parent = ext2_fh_to_parent,402 .get_parent = ext2_get_parent,403};404 405static unsigned long get_sb_block(void **data)406{407 unsigned long sb_block;408 char *options = (char *) *data;409 410 if (!options || strncmp(options, "sb=", 3) != 0)411 return 1; /* Default location */412 options += 3;413 sb_block = simple_strtoul(options, &options, 0);414 if (*options && *options != ',') {415 printk("EXT2-fs: Invalid sb specification: %s\n",416 (char *) *data);417 return 1;418 }419 if (*options == ',')420 options++;421 *data = (void *) options;422 return sb_block;423}424 425enum {426 Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,427 Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic,428 Opt_err_ro, Opt_nouid32, Opt_debug,429 Opt_oldalloc, Opt_orlov, Opt_nobh, Opt_user_xattr, Opt_nouser_xattr,430 Opt_acl, Opt_noacl, Opt_xip, Opt_dax, Opt_ignore, Opt_err, Opt_quota,431 Opt_usrquota, Opt_grpquota, Opt_reservation, Opt_noreservation432};433 434static const match_table_t tokens = {435 {Opt_bsd_df, "bsddf"},436 {Opt_minix_df, "minixdf"},437 {Opt_grpid, "grpid"},438 {Opt_grpid, "bsdgroups"},439 {Opt_nogrpid, "nogrpid"},440 {Opt_nogrpid, "sysvgroups"},441 {Opt_resgid, "resgid=%u"},442 {Opt_resuid, "resuid=%u"},443 {Opt_sb, "sb=%u"},444 {Opt_err_cont, "errors=continue"},445 {Opt_err_panic, "errors=panic"},446 {Opt_err_ro, "errors=remount-ro"},447 {Opt_nouid32, "nouid32"},448 {Opt_debug, "debug"},449 {Opt_oldalloc, "oldalloc"},450 {Opt_orlov, "orlov"},451 {Opt_nobh, "nobh"},452 {Opt_user_xattr, "user_xattr"},453 {Opt_nouser_xattr, "nouser_xattr"},454 {Opt_acl, "acl"},455 {Opt_noacl, "noacl"},456 {Opt_xip, "xip"},457 {Opt_dax, "dax"},458 {Opt_grpquota, "grpquota"},459 {Opt_ignore, "noquota"},460 {Opt_quota, "quota"},461 {Opt_usrquota, "usrquota"},462 {Opt_reservation, "reservation"},463 {Opt_noreservation, "noreservation"},464 {Opt_err, NULL}465};466 467static int parse_options(char *options, struct super_block *sb,468 struct ext2_mount_options *opts)469{470 char *p;471 substring_t args[MAX_OPT_ARGS];472 int option;473 kuid_t uid;474 kgid_t gid;475 476 if (!options)477 return 1;478 479 while ((p = strsep (&options, ",")) != NULL) {480 int token;481 if (!*p)482 continue;483 484 token = match_token(p, tokens, args);485 switch (token) {486 case Opt_bsd_df:487 clear_opt (opts->s_mount_opt, MINIX_DF);488 break;489 case Opt_minix_df:490 set_opt (opts->s_mount_opt, MINIX_DF);491 break;492 case Opt_grpid:493 set_opt (opts->s_mount_opt, GRPID);494 break;495 case Opt_nogrpid:496 clear_opt (opts->s_mount_opt, GRPID);497 break;498 case Opt_resuid:499 if (match_int(&args[0], &option))500 return 0;501 uid = make_kuid(current_user_ns(), option);502 if (!uid_valid(uid)) {503 ext2_msg(sb, KERN_ERR, "Invalid uid value %d", option);504 return 0;505 506 }507 opts->s_resuid = uid;508 break;509 case Opt_resgid:510 if (match_int(&args[0], &option))511 return 0;512 gid = make_kgid(current_user_ns(), option);513 if (!gid_valid(gid)) {514 ext2_msg(sb, KERN_ERR, "Invalid gid value %d", option);515 return 0;516 }517 opts->s_resgid = gid;518 break;519 case Opt_sb:520 /* handled by get_sb_block() instead of here */521 /* *sb_block = match_int(&args[0]); */522 break;523 case Opt_err_panic:524 clear_opt (opts->s_mount_opt, ERRORS_CONT);525 clear_opt (opts->s_mount_opt, ERRORS_RO);526 set_opt (opts->s_mount_opt, ERRORS_PANIC);527 break;528 case Opt_err_ro:529 clear_opt (opts->s_mount_opt, ERRORS_CONT);530 clear_opt (opts->s_mount_opt, ERRORS_PANIC);531 set_opt (opts->s_mount_opt, ERRORS_RO);532 break;533 case Opt_err_cont:534 clear_opt (opts->s_mount_opt, ERRORS_RO);535 clear_opt (opts->s_mount_opt, ERRORS_PANIC);536 set_opt (opts->s_mount_opt, ERRORS_CONT);537 break;538 case Opt_nouid32:539 set_opt (opts->s_mount_opt, NO_UID32);540 break;541 case Opt_debug:542 set_opt (opts->s_mount_opt, DEBUG);543 break;544 case Opt_oldalloc:545 set_opt (opts->s_mount_opt, OLDALLOC);546 break;547 case Opt_orlov:548 clear_opt (opts->s_mount_opt, OLDALLOC);549 break;550 case Opt_nobh:551 ext2_msg(sb, KERN_INFO,552 "nobh option not supported");553 break;554#ifdef CONFIG_EXT2_FS_XATTR555 case Opt_user_xattr:556 set_opt (opts->s_mount_opt, XATTR_USER);557 break;558 case Opt_nouser_xattr:559 clear_opt (opts->s_mount_opt, XATTR_USER);560 break;561#else562 case Opt_user_xattr:563 case Opt_nouser_xattr:564 ext2_msg(sb, KERN_INFO, "(no)user_xattr options"565 "not supported");566 break;567#endif568#ifdef CONFIG_EXT2_FS_POSIX_ACL569 case Opt_acl:570 set_opt(opts->s_mount_opt, POSIX_ACL);571 break;572 case Opt_noacl:573 clear_opt(opts->s_mount_opt, POSIX_ACL);574 break;575#else576 case Opt_acl:577 case Opt_noacl:578 ext2_msg(sb, KERN_INFO,579 "(no)acl options not supported");580 break;581#endif582 case Opt_xip:583 ext2_msg(sb, KERN_INFO, "use dax instead of xip");584 set_opt(opts->s_mount_opt, XIP);585 fallthrough;586 case Opt_dax:587#ifdef CONFIG_FS_DAX588 ext2_msg(sb, KERN_WARNING,589 "DAX enabled. Warning: EXPERIMENTAL, use at your own risk");590 set_opt(opts->s_mount_opt, DAX);591#else592 ext2_msg(sb, KERN_INFO, "dax option not supported");593#endif594 break;595 596#if defined(CONFIG_QUOTA)597 case Opt_quota:598 case Opt_usrquota:599 set_opt(opts->s_mount_opt, USRQUOTA);600 break;601 602 case Opt_grpquota:603 set_opt(opts->s_mount_opt, GRPQUOTA);604 break;605#else606 case Opt_quota:607 case Opt_usrquota:608 case Opt_grpquota:609 ext2_msg(sb, KERN_INFO,610 "quota operations not supported");611 break;612#endif613 614 case Opt_reservation:615 set_opt(opts->s_mount_opt, RESERVATION);616 ext2_msg(sb, KERN_INFO, "reservations ON");617 break;618 case Opt_noreservation:619 clear_opt(opts->s_mount_opt, RESERVATION);620 ext2_msg(sb, KERN_INFO, "reservations OFF");621 break;622 case Opt_ignore:623 break;624 default:625 return 0;626 }627 }628 return 1;629}630 631static int ext2_setup_super (struct super_block * sb,632 struct ext2_super_block * es,633 int read_only)634{635 int res = 0;636 struct ext2_sb_info *sbi = EXT2_SB(sb);637 638 if (le32_to_cpu(es->s_rev_level) > EXT2_MAX_SUPP_REV) {639 ext2_msg(sb, KERN_ERR,640 "error: revision level too high, "641 "forcing read-only mode");642 res = SB_RDONLY;643 }644 if (read_only)645 return res;646 if (!(sbi->s_mount_state & EXT2_VALID_FS))647 ext2_msg(sb, KERN_WARNING,648 "warning: mounting unchecked fs, "649 "running e2fsck is recommended");650 else if ((sbi->s_mount_state & EXT2_ERROR_FS))651 ext2_msg(sb, KERN_WARNING,652 "warning: mounting fs with errors, "653 "running e2fsck is recommended");654 else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 &&655 le16_to_cpu(es->s_mnt_count) >=656 (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))657 ext2_msg(sb, KERN_WARNING,658 "warning: maximal mount count reached, "659 "running e2fsck is recommended");660 else if (le32_to_cpu(es->s_checkinterval) &&661 (le32_to_cpu(es->s_lastcheck) +662 le32_to_cpu(es->s_checkinterval) <=663 ktime_get_real_seconds()))664 ext2_msg(sb, KERN_WARNING,665 "warning: checktime reached, "666 "running e2fsck is recommended");667 if (!le16_to_cpu(es->s_max_mnt_count))668 es->s_max_mnt_count = cpu_to_le16(EXT2_DFL_MAX_MNT_COUNT);669 le16_add_cpu(&es->s_mnt_count, 1);670 if (test_opt (sb, DEBUG))671 ext2_msg(sb, KERN_INFO, "%s, %s, bs=%lu, gc=%lu, "672 "bpg=%lu, ipg=%lu, mo=%04lx]",673 EXT2FS_VERSION, EXT2FS_DATE, sb->s_blocksize,674 sbi->s_groups_count,675 EXT2_BLOCKS_PER_GROUP(sb),676 EXT2_INODES_PER_GROUP(sb),677 sbi->s_mount_opt);678 return res;679}680 681static int ext2_check_descriptors(struct super_block *sb)682{683 int i;684 struct ext2_sb_info *sbi = EXT2_SB(sb);685 686 ext2_debug ("Checking group descriptors");687 688 for (i = 0; i < sbi->s_groups_count; i++) {689 struct ext2_group_desc *gdp = ext2_get_group_desc(sb, i, NULL);690 ext2_fsblk_t first_block = ext2_group_first_block_no(sb, i);691 ext2_fsblk_t last_block = ext2_group_last_block_no(sb, i);692 693 if (le32_to_cpu(gdp->bg_block_bitmap) < first_block ||694 le32_to_cpu(gdp->bg_block_bitmap) > last_block)695 {696 ext2_error (sb, "ext2_check_descriptors",697 "Block bitmap for group %d"698 " not in group (block %lu)!",699 i, (unsigned long) le32_to_cpu(gdp->bg_block_bitmap));700 return 0;701 }702 if (le32_to_cpu(gdp->bg_inode_bitmap) < first_block ||703 le32_to_cpu(gdp->bg_inode_bitmap) > last_block)704 {705 ext2_error (sb, "ext2_check_descriptors",706 "Inode bitmap for group %d"707 " not in group (block %lu)!",708 i, (unsigned long) le32_to_cpu(gdp->bg_inode_bitmap));709 return 0;710 }711 if (le32_to_cpu(gdp->bg_inode_table) < first_block ||712 le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group - 1 >713 last_block)714 {715 ext2_error (sb, "ext2_check_descriptors",716 "Inode table for group %d"717 " not in group (block %lu)!",718 i, (unsigned long) le32_to_cpu(gdp->bg_inode_table));719 return 0;720 }721 }722 return 1;723}724 725/*726 * Maximal file size. There is a direct, and {,double-,triple-}indirect727 * block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks.728 * We need to be 1 filesystem block less than the 2^32 sector limit.729 */730static loff_t ext2_max_size(int bits)731{732 loff_t res = EXT2_NDIR_BLOCKS;733 int meta_blocks;734 unsigned int upper_limit;735 unsigned int ppb = 1 << (bits-2);736 737 /* This is calculated to be the largest file size for a738 * dense, file such that the total number of739 * sectors in the file, including data and all indirect blocks,740 * does not exceed 2^32 -1741 * __u32 i_blocks representing the total number of742 * 512 bytes blocks of the file743 */744 upper_limit = (1LL << 32) - 1;745 746 /* total blocks in file system block size */747 upper_limit >>= (bits - 9);748 749 /* Compute how many blocks we can address by block tree */750 res += 1LL << (bits-2);751 res += 1LL << (2*(bits-2));752 res += 1LL << (3*(bits-2));753 /* Compute how many metadata blocks are needed */754 meta_blocks = 1;755 meta_blocks += 1 + ppb;756 meta_blocks += 1 + ppb + ppb * ppb;757 /* Does block tree limit file size? */758 if (res + meta_blocks <= upper_limit)759 goto check_lfs;760 761 res = upper_limit;762 /* How many metadata blocks are needed for addressing upper_limit? */763 upper_limit -= EXT2_NDIR_BLOCKS;764 /* indirect blocks */765 meta_blocks = 1;766 upper_limit -= ppb;767 /* double indirect blocks */768 if (upper_limit < ppb * ppb) {769 meta_blocks += 1 + DIV_ROUND_UP(upper_limit, ppb);770 res -= meta_blocks;771 goto check_lfs;772 }773 meta_blocks += 1 + ppb;774 upper_limit -= ppb * ppb;775 /* tripple indirect blocks for the rest */776 meta_blocks += 1 + DIV_ROUND_UP(upper_limit, ppb) +777 DIV_ROUND_UP(upper_limit, ppb*ppb);778 res -= meta_blocks;779check_lfs:780 res <<= bits;781 if (res > MAX_LFS_FILESIZE)782 res = MAX_LFS_FILESIZE;783 784 return res;785}786 787static unsigned long descriptor_loc(struct super_block *sb,788 unsigned long logic_sb_block,789 int nr)790{791 struct ext2_sb_info *sbi = EXT2_SB(sb);792 unsigned long bg, first_meta_bg;793 794 first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);795 796 if (!EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_META_BG) ||797 nr < first_meta_bg)798 return (logic_sb_block + nr + 1);799 bg = sbi->s_desc_per_block * nr;800 801 return ext2_group_first_block_no(sb, bg) + ext2_bg_has_super(sb, bg);802}803 804static int ext2_fill_super(struct super_block *sb, void *data, int silent)805{806 struct buffer_head * bh;807 struct ext2_sb_info * sbi;808 struct ext2_super_block * es;809 struct inode *root;810 unsigned long block;811 unsigned long sb_block = get_sb_block(&data);812 unsigned long logic_sb_block;813 unsigned long offset = 0;814 unsigned long def_mount_opts;815 long ret = -ENOMEM;816 int blocksize = BLOCK_SIZE;817 int db_count;818 int i, j;819 __le32 features;820 int err;821 struct ext2_mount_options opts;822 823 sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);824 if (!sbi)825 return -ENOMEM;826 827 sbi->s_blockgroup_lock =828 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);829 if (!sbi->s_blockgroup_lock) {830 kfree(sbi);831 return -ENOMEM;832 }833 sb->s_fs_info = sbi;834 sbi->s_sb_block = sb_block;835 sbi->s_daxdev = fs_dax_get_by_bdev(sb->s_bdev, &sbi->s_dax_part_off,836 NULL, NULL);837 838 spin_lock_init(&sbi->s_lock);839 ret = -EINVAL;840 841 /*842 * See what the current blocksize for the device is, and843 * use that as the blocksize. Otherwise (or if the blocksize844 * is smaller than the default) use the default.845 * This is important for devices that have a hardware846 * sectorsize that is larger than the default.847 */848 blocksize = sb_min_blocksize(sb, BLOCK_SIZE);849 if (!blocksize) {850 ext2_msg(sb, KERN_ERR, "error: unable to set blocksize");851 goto failed_sbi;852 }853 854 /*855 * If the superblock doesn't start on a hardware sector boundary,856 * calculate the offset. 857 */858 if (blocksize != BLOCK_SIZE) {859 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;860 offset = (sb_block*BLOCK_SIZE) % blocksize;861 } else {862 logic_sb_block = sb_block;863 }864 865 if (!(bh = sb_bread(sb, logic_sb_block))) {866 ext2_msg(sb, KERN_ERR, "error: unable to read superblock");867 goto failed_sbi;868 }869 /*870 * Note: s_es must be initialized as soon as possible because871 * some ext2 macro-instructions depend on its value872 */873 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);874 sbi->s_es = es;875 sb->s_magic = le16_to_cpu(es->s_magic);876 877 if (sb->s_magic != EXT2_SUPER_MAGIC)878 goto cantfind_ext2;879 880 opts.s_mount_opt = 0;881 /* Set defaults before we parse the mount options */882 def_mount_opts = le32_to_cpu(es->s_default_mount_opts);883 if (def_mount_opts & EXT2_DEFM_DEBUG)884 set_opt(opts.s_mount_opt, DEBUG);885 if (def_mount_opts & EXT2_DEFM_BSDGROUPS)886 set_opt(opts.s_mount_opt, GRPID);887 if (def_mount_opts & EXT2_DEFM_UID16)888 set_opt(opts.s_mount_opt, NO_UID32);889#ifdef CONFIG_EXT2_FS_XATTR890 if (def_mount_opts & EXT2_DEFM_XATTR_USER)891 set_opt(opts.s_mount_opt, XATTR_USER);892#endif893#ifdef CONFIG_EXT2_FS_POSIX_ACL894 if (def_mount_opts & EXT2_DEFM_ACL)895 set_opt(opts.s_mount_opt, POSIX_ACL);896#endif897 898 if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_PANIC)899 set_opt(opts.s_mount_opt, ERRORS_PANIC);900 else if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_CONTINUE)901 set_opt(opts.s_mount_opt, ERRORS_CONT);902 else903 set_opt(opts.s_mount_opt, ERRORS_RO);904 905 opts.s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));906 opts.s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));907 908 set_opt(opts.s_mount_opt, RESERVATION);909 910 if (!parse_options((char *) data, sb, &opts))911 goto failed_mount;912 913 sbi->s_mount_opt = opts.s_mount_opt;914 sbi->s_resuid = opts.s_resuid;915 sbi->s_resgid = opts.s_resgid;916 917 sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |918 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);919 sb->s_iflags |= SB_I_CGROUPWB;920 921 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV &&922 (EXT2_HAS_COMPAT_FEATURE(sb, ~0U) ||923 EXT2_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||924 EXT2_HAS_INCOMPAT_FEATURE(sb, ~0U)))925 ext2_msg(sb, KERN_WARNING,926 "warning: feature flags set on rev 0 fs, "927 "running e2fsck is recommended");928 /*929 * Check feature flags regardless of the revision level, since we930 * previously didn't change the revision level when setting the flags,931 * so there is a chance incompat flags are set on a rev 0 filesystem.932 */933 features = EXT2_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP);934 if (features) {935 ext2_msg(sb, KERN_ERR, "error: couldn't mount because of "936 "unsupported optional features (%x)",937 le32_to_cpu(features));938 goto failed_mount;939 }940 if (!sb_rdonly(sb) && (features = EXT2_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))){941 ext2_msg(sb, KERN_ERR, "error: couldn't mount RDWR because of "942 "unsupported optional features (%x)",943 le32_to_cpu(features));944 goto failed_mount;945 }946 947 if (le32_to_cpu(es->s_log_block_size) >948 (EXT2_MAX_BLOCK_LOG_SIZE - BLOCK_SIZE_BITS)) {949 ext2_msg(sb, KERN_ERR,950 "Invalid log block size: %u",951 le32_to_cpu(es->s_log_block_size));952 goto failed_mount;953 }954 blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);955 956 if (test_opt(sb, DAX)) {957 if (!sbi->s_daxdev) {958 ext2_msg(sb, KERN_ERR,959 "DAX unsupported by block device. Turning off DAX.");960 clear_opt(sbi->s_mount_opt, DAX);961 } else if (blocksize != PAGE_SIZE) {962 ext2_msg(sb, KERN_ERR, "unsupported blocksize for DAX\n");963 clear_opt(sbi->s_mount_opt, DAX);964 }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 sb->s_time_min = S32_MIN;996 sb->s_time_max = S32_MAX;997 998 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV) {999 sbi->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE;1000 sbi->s_first_ino = EXT2_GOOD_OLD_FIRST_INO;1001 } else {1002 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);1003 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);1004 if ((sbi->s_inode_size < EXT2_GOOD_OLD_INODE_SIZE) ||1005 !is_power_of_2(sbi->s_inode_size) ||1006 (sbi->s_inode_size > blocksize)) {1007 ext2_msg(sb, KERN_ERR,1008 "error: unsupported inode size: %d",1009 sbi->s_inode_size);1010 goto failed_mount;1011 }1012 }1013 1014 sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);1015 sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);1016 1017 sbi->s_inodes_per_block = sb->s_blocksize / EXT2_INODE_SIZE(sb);1018 if (sbi->s_inodes_per_block == 0 || sbi->s_inodes_per_group == 0)1019 goto cantfind_ext2;1020 sbi->s_itb_per_group = sbi->s_inodes_per_group /1021 sbi->s_inodes_per_block;1022 sbi->s_desc_per_block = sb->s_blocksize /1023 sizeof (struct ext2_group_desc);1024 sbi->s_sbh = bh;1025 sbi->s_mount_state = le16_to_cpu(es->s_state);1026 sbi->s_addr_per_block_bits =1027 ilog2 (EXT2_ADDR_PER_BLOCK(sb));1028 sbi->s_desc_per_block_bits =1029 ilog2 (EXT2_DESC_PER_BLOCK(sb));1030 1031 if (sb->s_magic != EXT2_SUPER_MAGIC)1032 goto cantfind_ext2;1033 1034 if (sb->s_blocksize != bh->b_size) {1035 if (!silent)1036 ext2_msg(sb, KERN_ERR, "error: unsupported blocksize");1037 goto failed_mount;1038 }1039 1040 if (es->s_log_frag_size != es->s_log_block_size) {1041 ext2_msg(sb, KERN_ERR,1042 "error: fragsize log %u != blocksize log %u",1043 le32_to_cpu(es->s_log_frag_size), sb->s_blocksize_bits);1044 goto failed_mount;1045 }1046 1047 if (sbi->s_blocks_per_group > sb->s_blocksize * 8) {1048 ext2_msg(sb, KERN_ERR,1049 "error: #blocks per group too big: %lu",1050 sbi->s_blocks_per_group);1051 goto failed_mount;1052 }1053 /* At least inode table, bitmaps, and sb have to fit in one group */1054 if (sbi->s_blocks_per_group <= sbi->s_itb_per_group + 3) {1055 ext2_msg(sb, KERN_ERR,1056 "error: #blocks per group smaller than metadata size: %lu <= %lu",1057 sbi->s_blocks_per_group, sbi->s_inodes_per_group + 3);1058 goto failed_mount;1059 }1060 if (sbi->s_inodes_per_group < sbi->s_inodes_per_block ||1061 sbi->s_inodes_per_group > sb->s_blocksize * 8) {1062 ext2_msg(sb, KERN_ERR,1063 "error: invalid #inodes per group: %lu",1064 sbi->s_inodes_per_group);1065 goto failed_mount;1066 }1067 if (sb_bdev_nr_blocks(sb) < le32_to_cpu(es->s_blocks_count)) {1068 ext2_msg(sb, KERN_ERR,1069 "bad geometry: block count %u exceeds size of device (%u blocks)",1070 le32_to_cpu(es->s_blocks_count),1071 (unsigned)sb_bdev_nr_blocks(sb));1072 goto failed_mount;1073 }1074 1075 sbi->s_groups_count = ((le32_to_cpu(es->s_blocks_count) -1076 le32_to_cpu(es->s_first_data_block) - 1)1077 / EXT2_BLOCKS_PER_GROUP(sb)) + 1;1078 if ((u64)sbi->s_groups_count * sbi->s_inodes_per_group !=1079 le32_to_cpu(es->s_inodes_count)) {1080 ext2_msg(sb, KERN_ERR, "error: invalid #inodes: %u vs computed %llu",1081 le32_to_cpu(es->s_inodes_count),1082 (u64)sbi->s_groups_count * sbi->s_inodes_per_group);1083 goto failed_mount;1084 }1085 db_count = (sbi->s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) /1086 EXT2_DESC_PER_BLOCK(sb);1087 sbi->s_group_desc = kvmalloc_array(db_count,1088 sizeof(struct buffer_head *),1089 GFP_KERNEL);1090 if (sbi->s_group_desc == NULL) {1091 ret = -ENOMEM;1092 ext2_msg(sb, KERN_ERR, "error: not enough memory");1093 goto failed_mount;1094 }1095 bgl_lock_init(sbi->s_blockgroup_lock);1096 sbi->s_debts = kcalloc(sbi->s_groups_count, sizeof(*sbi->s_debts), GFP_KERNEL);1097 if (!sbi->s_debts) {1098 ret = -ENOMEM;1099 ext2_msg(sb, KERN_ERR, "error: not enough memory");1100 goto failed_mount_group_desc;1101 }1102 for (i = 0; i < db_count; i++) {1103 block = descriptor_loc(sb, logic_sb_block, i);1104 sbi->s_group_desc[i] = sb_bread(sb, block);1105 if (!sbi->s_group_desc[i]) {1106 for (j = 0; j < i; j++)1107 brelse (sbi->s_group_desc[j]);1108 ext2_msg(sb, KERN_ERR,1109 "error: unable to read group descriptors");1110 goto failed_mount_group_desc;1111 }1112 }1113 if (!ext2_check_descriptors (sb)) {1114 ext2_msg(sb, KERN_ERR, "group descriptors corrupted");1115 goto failed_mount2;1116 }1117 sbi->s_gdb_count = db_count;1118 get_random_bytes(&sbi->s_next_generation, sizeof(u32));1119 spin_lock_init(&sbi->s_next_gen_lock);1120 1121 /* per filesystem reservation list head & lock */1122 spin_lock_init(&sbi->s_rsv_window_lock);1123 sbi->s_rsv_window_root = RB_ROOT;1124 /*1125 * Add a single, static dummy reservation to the start of the1126 * reservation window list --- it gives us a placeholder for1127 * append-at-start-of-list which makes the allocation logic1128 * _much_ simpler.1129 */1130 sbi->s_rsv_window_head.rsv_start = EXT2_RESERVE_WINDOW_NOT_ALLOCATED;1131 sbi->s_rsv_window_head.rsv_end = EXT2_RESERVE_WINDOW_NOT_ALLOCATED;1132 sbi->s_rsv_window_head.rsv_alloc_hit = 0;1133 sbi->s_rsv_window_head.rsv_goal_size = 0;1134 ext2_rsv_window_add(sb, &sbi->s_rsv_window_head);1135 1136 err = percpu_counter_init(&sbi->s_freeblocks_counter,1137 ext2_count_free_blocks(sb), GFP_KERNEL);1138 if (!err) {1139 err = percpu_counter_init(&sbi->s_freeinodes_counter,1140 ext2_count_free_inodes(sb), GFP_KERNEL);1141 }1142 if (!err) {1143 err = percpu_counter_init(&sbi->s_dirs_counter,1144 ext2_count_dirs(sb), GFP_KERNEL);1145 }1146 if (err) {1147 ret = err;1148 ext2_msg(sb, KERN_ERR, "error: insufficient memory");1149 goto failed_mount3;1150 }1151 1152#ifdef CONFIG_EXT2_FS_XATTR1153 sbi->s_ea_block_cache = ext2_xattr_create_cache();1154 if (!sbi->s_ea_block_cache) {1155 ret = -ENOMEM;1156 ext2_msg(sb, KERN_ERR, "Failed to create ea_block_cache");1157 goto failed_mount3;1158 }1159#endif1160 /*1161 * set up enough so that it can read an inode1162 */1163 sb->s_op = &ext2_sops;1164 sb->s_export_op = &ext2_export_ops;1165 sb->s_xattr = ext2_xattr_handlers;1166 1167#ifdef CONFIG_QUOTA1168 sb->dq_op = &dquot_operations;1169 sb->s_qcop = &ext2_quotactl_ops;1170 sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP;1171#endif1172 1173 root = ext2_iget(sb, EXT2_ROOT_INO);1174 if (IS_ERR(root)) {1175 ret = PTR_ERR(root);1176 goto failed_mount3;1177 }1178 if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {1179 iput(root);1180 ext2_msg(sb, KERN_ERR, "error: corrupt root inode, run e2fsck");1181 goto failed_mount3;1182 }1183 1184 sb->s_root = d_make_root(root);1185 if (!sb->s_root) {1186 ext2_msg(sb, KERN_ERR, "error: get root inode failed");1187 ret = -ENOMEM;1188 goto failed_mount3;1189 }1190 if (EXT2_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_HAS_JOURNAL))1191 ext2_msg(sb, KERN_WARNING,1192 "warning: mounting ext3 filesystem as ext2");1193 if (ext2_setup_super (sb, es, sb_rdonly(sb)))1194 sb->s_flags |= SB_RDONLY;1195 ext2_write_super(sb);1196 return 0;1197 1198cantfind_ext2:1199 if (!silent)1200 ext2_msg(sb, KERN_ERR,1201 "error: can't find an ext2 filesystem on dev %s.",1202 sb->s_id);1203 goto failed_mount;1204failed_mount3:1205 ext2_xattr_destroy_cache(sbi->s_ea_block_cache);1206 percpu_counter_destroy(&sbi->s_freeblocks_counter);1207 percpu_counter_destroy(&sbi->s_freeinodes_counter);1208 percpu_counter_destroy(&sbi->s_dirs_counter);1209failed_mount2:1210 for (i = 0; i < db_count; i++)1211 brelse(sbi->s_group_desc[i]);1212failed_mount_group_desc:1213 kvfree(sbi->s_group_desc);1214 kfree(sbi->s_debts);1215failed_mount:1216 brelse(bh);1217failed_sbi:1218 fs_put_dax(sbi->s_daxdev, NULL);1219 sb->s_fs_info = NULL;1220 kfree(sbi->s_blockgroup_lock);1221 kfree(sbi);1222 return ret;1223}1224 1225static void ext2_clear_super_error(struct super_block *sb)1226{1227 struct buffer_head *sbh = EXT2_SB(sb)->s_sbh;1228 1229 if (buffer_write_io_error(sbh)) {1230 /*1231 * Oh, dear. A previous attempt to write the1232 * superblock failed. This could happen because the1233 * USB device was yanked out. Or it could happen to1234 * be a transient write error and maybe the block will1235 * be remapped. Nothing we can do but to retry the1236 * write and hope for the best.1237 */1238 ext2_msg(sb, KERN_ERR,1239 "previous I/O error to superblock detected");1240 clear_buffer_write_io_error(sbh);1241 set_buffer_uptodate(sbh);1242 }1243}1244 1245void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es,1246 int wait)1247{1248 ext2_clear_super_error(sb);1249 spin_lock(&EXT2_SB(sb)->s_lock);1250 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb));1251 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb));1252 es->s_wtime = cpu_to_le32(ktime_get_real_seconds());1253 /* unlock before we do IO */1254 spin_unlock(&EXT2_SB(sb)->s_lock);1255 mark_buffer_dirty(EXT2_SB(sb)->s_sbh);1256 if (wait)1257 sync_dirty_buffer(EXT2_SB(sb)->s_sbh);1258}1259 1260/*1261 * In the second extended file system, it is not necessary to1262 * write the super block since we use a mapping of the1263 * disk super block in a buffer.1264 *1265 * However, this function is still used to set the fs valid1266 * flags to 0. We need to set this flag to 0 since the fs1267 * may have been checked while mounted and e2fsck may have1268 * set s_state to EXT2_VALID_FS after some corrections.1269 */1270static int ext2_sync_fs(struct super_block *sb, int wait)1271{1272 struct ext2_sb_info *sbi = EXT2_SB(sb);1273 struct ext2_super_block *es = EXT2_SB(sb)->s_es;1274 1275 /*1276 * Write quota structures to quota file, sync_blockdev() will write1277 * them to disk later1278 */1279 dquot_writeback_dquots(sb, -1);1280 1281 spin_lock(&sbi->s_lock);1282 if (es->s_state & cpu_to_le16(EXT2_VALID_FS)) {1283 ext2_debug("setting valid to 0\n");1284 es->s_state &= cpu_to_le16(~EXT2_VALID_FS);1285 }1286 spin_unlock(&sbi->s_lock);1287 ext2_sync_super(sb, es, wait);1288 return 0;1289}1290 1291static int ext2_freeze(struct super_block *sb)1292{1293 struct ext2_sb_info *sbi = EXT2_SB(sb);1294 1295 /*1296 * Open but unlinked files present? Keep EXT2_VALID_FS flag cleared1297 * because we have unattached inodes and thus filesystem is not fully1298 * consistent.1299 */1300 if (atomic_long_read(&sb->s_remove_count)) {1301 ext2_sync_fs(sb, 1);1302 return 0;1303 }1304 /* Set EXT2_FS_VALID flag */1305 spin_lock(&sbi->s_lock);1306 sbi->s_es->s_state = cpu_to_le16(sbi->s_mount_state);1307 spin_unlock(&sbi->s_lock);1308 ext2_sync_super(sb, sbi->s_es, 1);1309 1310 return 0;1311}1312 1313static int ext2_unfreeze(struct super_block *sb)1314{1315 /* Just write sb to clear EXT2_VALID_FS flag */1316 ext2_write_super(sb);1317 1318 return 0;1319}1320 1321static void ext2_write_super(struct super_block *sb)1322{1323 if (!sb_rdonly(sb))1324 ext2_sync_fs(sb, 1);1325}1326 1327static int ext2_remount (struct super_block * sb, int * flags, char * data)1328{1329 struct ext2_sb_info * sbi = EXT2_SB(sb);1330 struct ext2_super_block * es;1331 struct ext2_mount_options new_opts;1332 int err;1333 1334 sync_filesystem(sb);1335 1336 spin_lock(&sbi->s_lock);1337 new_opts.s_mount_opt = sbi->s_mount_opt;1338 new_opts.s_resuid = sbi->s_resuid;1339 new_opts.s_resgid = sbi->s_resgid;1340 spin_unlock(&sbi->s_lock);1341 1342 if (!parse_options(data, sb, &new_opts))1343 return -EINVAL;1344 1345 spin_lock(&sbi->s_lock);1346 es = sbi->s_es;1347 if ((sbi->s_mount_opt ^ new_opts.s_mount_opt) & EXT2_MOUNT_DAX) {1348 ext2_msg(sb, KERN_WARNING, "warning: refusing change of "1349 "dax flag with busy inodes while remounting");1350 new_opts.s_mount_opt ^= EXT2_MOUNT_DAX;1351 }1352 if ((bool)(*flags & SB_RDONLY) == sb_rdonly(sb))1353 goto out_set;1354 if (*flags & SB_RDONLY) {1355 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS ||1356 !(sbi->s_mount_state & EXT2_VALID_FS))1357 goto out_set;1358 1359 /*1360 * OK, we are remounting a valid rw partition rdonly, so set1361 * the rdonly flag and then mark the partition as valid again.1362 */1363 es->s_state = cpu_to_le16(sbi->s_mount_state);1364 es->s_mtime = cpu_to_le32(ktime_get_real_seconds());1365 spin_unlock(&sbi->s_lock);1366 1367 err = dquot_suspend(sb, -1);1368 if (err < 0)1369 return err;1370 1371 ext2_sync_super(sb, es, 1);1372 } else {1373 __le32 ret = EXT2_HAS_RO_COMPAT_FEATURE(sb,1374 ~EXT2_FEATURE_RO_COMPAT_SUPP);1375 if (ret) {1376 spin_unlock(&sbi->s_lock);1377 ext2_msg(sb, KERN_WARNING,1378 "warning: couldn't remount RDWR because of "1379 "unsupported optional features (%x).",1380 le32_to_cpu(ret));1381 return -EROFS;1382 }1383 /*1384 * Mounting a RDONLY partition read-write, so reread and1385 * store the current valid flag. (It may have been changed1386 * by e2fsck since we originally mounted the partition.)1387 */1388 sbi->s_mount_state = le16_to_cpu(es->s_state);1389 if (!ext2_setup_super (sb, es, 0))1390 sb->s_flags &= ~SB_RDONLY;1391 spin_unlock(&sbi->s_lock);1392 1393 ext2_write_super(sb);1394 1395 dquot_resume(sb, -1);1396 }1397 1398 spin_lock(&sbi->s_lock);1399out_set:1400 sbi->s_mount_opt = new_opts.s_mount_opt;1401 sbi->s_resuid = new_opts.s_resuid;1402 sbi->s_resgid = new_opts.s_resgid;1403 sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |1404 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);1405 spin_unlock(&sbi->s_lock);1406 1407 return 0;1408}1409 1410static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf)1411{1412 struct super_block *sb = dentry->d_sb;1413 struct ext2_sb_info *sbi = EXT2_SB(sb);1414 struct ext2_super_block *es = sbi->s_es;1415 1416 spin_lock(&sbi->s_lock);1417 1418 if (test_opt (sb, MINIX_DF))1419 sbi->s_overhead_last = 0;1420 else if (sbi->s_blocks_last != le32_to_cpu(es->s_blocks_count)) {1421 unsigned long i, overhead = 0;1422 smp_rmb();1423 1424 /*1425 * Compute the overhead (FS structures). This is constant1426 * for a given filesystem unless the number of block groups1427 * changes so we cache the previous value until it does.1428 */1429 1430 /*1431 * All of the blocks before first_data_block are1432 * overhead1433 */1434 overhead = le32_to_cpu(es->s_first_data_block);1435 1436 /*1437 * Add the overhead attributed to the superblock and1438 * block group descriptors. If the sparse superblocks1439 * feature is turned on, then not all groups have this.1440 */1441 for (i = 0; i < sbi->s_groups_count; i++)1442 overhead += ext2_bg_has_super(sb, i) +1443 ext2_bg_num_gdb(sb, i);1444 1445 /*1446 * Every block group has an inode bitmap, a block1447 * bitmap, and an inode table.1448 */1449 overhead += (sbi->s_groups_count *1450 (2 + sbi->s_itb_per_group));1451 sbi->s_overhead_last = overhead;1452 smp_wmb();1453 sbi->s_blocks_last = le32_to_cpu(es->s_blocks_count);1454 }1455 1456 buf->f_type = EXT2_SUPER_MAGIC;1457 buf->f_bsize = sb->s_blocksize;1458 buf->f_blocks = le32_to_cpu(es->s_blocks_count) - sbi->s_overhead_last;1459 buf->f_bfree = ext2_count_free_blocks(sb);1460 es->s_free_blocks_count = cpu_to_le32(buf->f_bfree);1461 buf->f_bavail = buf->f_bfree - le32_to_cpu(es->s_r_blocks_count);1462 if (buf->f_bfree < le32_to_cpu(es->s_r_blocks_count))1463 buf->f_bavail = 0;1464 buf->f_files = le32_to_cpu(es->s_inodes_count);1465 buf->f_ffree = ext2_count_free_inodes(sb);1466 es->s_free_inodes_count = cpu_to_le32(buf->f_ffree);1467 buf->f_namelen = EXT2_NAME_LEN;1468 buf->f_fsid = uuid_to_fsid(es->s_uuid);1469 spin_unlock(&sbi->s_lock);1470 return 0;1471}1472 1473static struct dentry *ext2_mount(struct file_system_type *fs_type,1474 int flags, const char *dev_name, void *data)1475{1476 return mount_bdev(fs_type, flags, dev_name, data, ext2_fill_super);1477}1478 1479#ifdef CONFIG_QUOTA1480 1481/* Read data from quotafile - avoid pagecache and such because we cannot afford1482 * acquiring the locks... As quota files are never truncated and quota code1483 * itself serializes the operations (and no one else should touch the files)1484 * we don't have to be afraid of races */1485static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data,1486 size_t len, loff_t off)1487{1488 struct inode *inode = sb_dqopt(sb)->files[type];1489 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb);1490 int err = 0;1491 int offset = off & (sb->s_blocksize - 1);1492 int tocopy;1493 size_t toread;1494 struct buffer_head tmp_bh;1495 struct buffer_head *bh;1496 loff_t i_size = i_size_read(inode);1497 1498 if (off > i_size)1499 return 0;1500 if (off+len > i_size)1501 len = i_size-off;1502 toread = len;1503 while (toread > 0) {1504 tocopy = min_t(size_t, sb->s_blocksize - offset, toread);1505 1506 tmp_bh.b_state = 0;1507 tmp_bh.b_size = sb->s_blocksize;1508 err = ext2_get_block(inode, blk, &tmp_bh, 0);1509 if (err < 0)1510 return err;1511 if (!buffer_mapped(&tmp_bh)) /* A hole? */1512 memset(data, 0, tocopy);1513 else {1514 bh = sb_bread(sb, tmp_bh.b_blocknr);1515 if (!bh)1516 return -EIO;1517 memcpy(data, bh->b_data+offset, tocopy);1518 brelse(bh);1519 }1520 offset = 0;1521 toread -= tocopy;1522 data += tocopy;1523 blk++;1524 }1525 return len;1526}1527 1528/* Write to quotafile */1529static ssize_t ext2_quota_write(struct super_block *sb, int type,1530 const char *data, size_t len, loff_t off)1531{1532 struct inode *inode = sb_dqopt(sb)->files[type];1533 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb);1534 int err = 0;1535 int offset = off & (sb->s_blocksize - 1);1536 int tocopy;1537 size_t towrite = len;1538 struct buffer_head tmp_bh;1539 struct buffer_head *bh;1540 1541 while (towrite > 0) {1542 tocopy = min_t(size_t, sb->s_blocksize - offset, towrite);1543 1544 tmp_bh.b_state = 0;1545 tmp_bh.b_size = sb->s_blocksize;1546 err = ext2_get_block(inode, blk, &tmp_bh, 1);1547 if (err < 0)1548 goto out;1549 if (offset || tocopy != EXT2_BLOCK_SIZE(sb))1550 bh = sb_bread(sb, tmp_bh.b_blocknr);1551 else1552 bh = sb_getblk(sb, tmp_bh.b_blocknr);1553 if (unlikely(!bh)) {1554 err = -EIO;1555 goto out;1556 }1557 lock_buffer(bh);1558 memcpy(bh->b_data+offset, data, tocopy);1559 flush_dcache_page(bh->b_page);1560 set_buffer_uptodate(bh);1561 mark_buffer_dirty(bh);1562 unlock_buffer(bh);1563 brelse(bh);1564 offset = 0;1565 towrite -= tocopy;1566 data += tocopy;1567 blk++;1568 }1569out:1570 if (len == towrite)1571 return err;1572 if (inode->i_size < off+len-towrite)1573 i_size_write(inode, off+len-towrite);1574 inode_inc_iversion(inode);1575 inode_set_mtime_to_ts(inode, inode_set_ctime_current(inode));1576 mark_inode_dirty(inode);1577 return len - towrite;1578}1579 1580static int ext2_quota_on(struct super_block *sb, int type, int format_id,1581 const struct path *path)1582{1583 int err;1584 struct inode *inode;1585 1586 err = dquot_quota_on(sb, type, format_id, path);1587 if (err)1588 return err;1589 1590 inode = d_inode(path->dentry);1591 inode_lock(inode);1592 EXT2_I(inode)->i_flags |= EXT2_NOATIME_FL | EXT2_IMMUTABLE_FL;1593 inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,1594 S_NOATIME | S_IMMUTABLE);1595 inode_unlock(inode);1596 mark_inode_dirty(inode);1597 1598 return 0;1599}1600 1601static int ext2_quota_off(struct super_block *sb, int type)1602{1603 struct inode *inode = sb_dqopt(sb)->files[type];1604 int err;1605 1606 if (!inode || !igrab(inode))1607 goto out;1608 1609 err = dquot_quota_off(sb, type);1610 if (err)1611 goto out_put;1612 1613 inode_lock(inode);1614 EXT2_I(inode)->i_flags &= ~(EXT2_NOATIME_FL | EXT2_IMMUTABLE_FL);1615 inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);1616 inode_unlock(inode);1617 mark_inode_dirty(inode);1618out_put:1619 iput(inode);1620 return err;1621out:1622 return dquot_quota_off(sb, type);1623}1624 1625#endif1626 1627static struct file_system_type ext2_fs_type = {1628 .owner = THIS_MODULE,1629 .name = "ext2",1630 .mount = ext2_mount,1631 .kill_sb = kill_block_super,1632 .fs_flags = FS_REQUIRES_DEV,1633};1634MODULE_ALIAS_FS("ext2");1635 1636static int __init init_ext2_fs(void)1637{1638 int err;1639 1640 err = init_inodecache();1641 if (err)1642 return err;1643 err = register_filesystem(&ext2_fs_type);1644 if (err)1645 goto out;1646 return 0;1647out:1648 destroy_inodecache();1649 return err;1650}1651 1652static void __exit exit_ext2_fs(void)1653{1654 unregister_filesystem(&ext2_fs_type);1655 destroy_inodecache();1656}1657 1658MODULE_AUTHOR("Remy Card and others");1659MODULE_DESCRIPTION("Second Extended Filesystem");1660MODULE_LICENSE("GPL");1661module_init(init_ext2_fs)1662module_exit(exit_ext2_fs)1663