--- /dev/null
+/*
+ * linux/fs/ext2/super.c
+ *
+ * Copyright (C) 1992, 1993, 1994, 1995
+ * Remy Card (card@masi.ibp.fr)
+ * Laboratoire MASI - Institut Blaise Pascal
+ * Universite Pierre et Marie Curie (Paris VI)
+ *
+ * from
+ *
+ * linux/fs/minix/inode.c
+ *
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ *
+ * Big-endian to little-endian byte-swapping/bitmaps by
+ * David S. Miller (davem@caip.rutgers.edu), 1995
+ */
+
+#include <linux/module.h>
+#include <linux/string.h>
+#include <linux/fs.h>
+#include <linux/slab.h>
+#include <linux/init.h>
+#include <linux/blkdev.h>
+#include <linux/parser.h>
+#include <linux/random.h>
+#include <linux/buffer_head.h>
+#include <linux/exportfs.h>
+#include <linux/vfs.h>
+#include <linux/seq_file.h>
+#include <linux/mount.h>
+#include <linux/log2.h>
+#include <linux/quotaops.h>
+#include <asm/uaccess.h>
+#include "ext2.h"
+#include "xattr.h"
+#include "acl.h"
+
+static void ext2_sync_super(struct super_block *sb,
+ struct ext2_super_block *es, int wait);
+static int ext2_remount (struct super_block * sb, int * flags, char * data);
+static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf);
+static int ext2_sync_fs(struct super_block *sb, int wait);
+static int ext2_freeze(struct super_block *sb);
+static int ext2_unfreeze(struct super_block *sb);
+
+void ext2_error(struct super_block *sb, const char *function,
+ const char *fmt, ...)
+{
+ struct va_format vaf;
+ va_list args;
+ struct ext2_sb_info *sbi = EXT2_SB(sb);
+ struct ext2_super_block *es = sbi->s_es;
+
+ if (!(sb->s_flags & MS_RDONLY)) {
+ spin_lock(&sbi->s_lock);
+ sbi->s_mount_state |= EXT2_ERROR_FS;
+ es->s_state |= cpu_to_le16(EXT2_ERROR_FS);
+ spin_unlock(&sbi->s_lock);
+ ext2_sync_super(sb, es, 1);
+ }
+
+ va_start(args, fmt);
+
+ vaf.fmt = fmt;
+ vaf.va = &args;
+
+ printk(KERN_CRIT "EXT2-fs (%s): error: %s: %pV\n",
+ sb->s_id, function, &vaf);
+
+ va_end(args);
+
+ if (test_opt(sb, ERRORS_PANIC))
+ panic("EXT2-fs: panic from previous error\n");
+ if (test_opt(sb, ERRORS_RO)) {
+ ext2_msg(sb, KERN_CRIT,
+ "error: remounting filesystem read-only");
+ sb->s_flags |= MS_RDONLY;
+ }
+}
+
+void ext2_msg(struct super_block *sb, const char *prefix,
+ const char *fmt, ...)
+{
+ struct va_format vaf;
+ va_list args;
+
+ va_start(args, fmt);
+
+ vaf.fmt = fmt;
+ vaf.va = &args;
+
+ printk("%sEXT2-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
+
+ va_end(args);
+}
+
+/*
+ * This must be called with sbi->s_lock held.
+ */
+void ext2_update_dynamic_rev(struct super_block *sb)
+{
+ struct ext2_super_block *es = EXT2_SB(sb)->s_es;
+
+ if (le32_to_cpu(es->s_rev_level) > EXT2_GOOD_OLD_REV)
+ return;
+
+ ext2_msg(sb, KERN_WARNING,
+ "warning: updating to rev %d because of "
+ "new feature flag, running e2fsck is recommended",
+ EXT2_DYNAMIC_REV);
+
+ es->s_first_ino = cpu_to_le32(EXT2_GOOD_OLD_FIRST_INO);
+ es->s_inode_size = cpu_to_le16(EXT2_GOOD_OLD_INODE_SIZE);
+ es->s_rev_level = cpu_to_le32(EXT2_DYNAMIC_REV);
+ /* leave es->s_feature_*compat flags alone */
+ /* es->s_uuid will be set by e2fsck if empty */
+
+ /*
+ * The rest of the superblock fields should be zero, and if not it
+ * means they are likely already in use, so leave them alone. We
+ * can leave it up to e2fsck to clean up any inconsistencies there.
+ */
+}
+
+static void ext2_put_super (struct super_block * sb)
+{
+ int db_count;
+ int i;
+ struct ext2_sb_info *sbi = EXT2_SB(sb);
+
+ dquot_disable(sb, -1, DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED);
+
+ ext2_xattr_put_super(sb);
+ if (!(sb->s_flags & MS_RDONLY)) {
+ struct ext2_super_block *es = sbi->s_es;
+
+ spin_lock(&sbi->s_lock);
+ es->s_state = cpu_to_le16(sbi->s_mount_state);
+ spin_unlock(&sbi->s_lock);
+ ext2_sync_super(sb, es, 1);
+ }
+ db_count = sbi->s_gdb_count;
+ for (i = 0; i < db_count; i++)
+ if (sbi->s_group_desc[i])
+ brelse (sbi->s_group_desc[i]);
+ kfree(sbi->s_group_desc);
+ kfree(sbi->s_debts);
+ percpu_counter_destroy(&sbi->s_freeblocks_counter);
+ percpu_counter_destroy(&sbi->s_freeinodes_counter);
+ percpu_counter_destroy(&sbi->s_dirs_counter);
+ brelse (sbi->s_sbh);
+ sb->s_fs_info = NULL;
+ kfree(sbi->s_blockgroup_lock);
+ kfree(sbi);
+}
+
+static struct kmem_cache * ext2_inode_cachep;
+
+static struct inode *ext2_alloc_inode(struct super_block *sb)
+{
+ struct ext2_inode_info *ei;
+ ei = kmem_cache_alloc(ext2_inode_cachep, GFP_KERNEL);
+ if (!ei)
+ return NULL;
+ ei->i_block_alloc_info = NULL;
+ ei->vfs_inode.i_version = 1;
+#ifdef CONFIG_QUOTA
+ memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
+#endif
+
+ return &ei->vfs_inode;
+}
+
+static void ext2_i_callback(struct rcu_head *head)
+{
+ struct inode *inode = container_of(head, struct inode, i_rcu);
+ kmem_cache_free(ext2_inode_cachep, EXT2_I(inode));
+}
+
+static void ext2_destroy_inode(struct inode *inode)
+{
+ call_rcu(&inode->i_rcu, ext2_i_callback);
+}
+
+static void init_once(void *foo)
+{
+ struct ext2_inode_info *ei = (struct ext2_inode_info *) foo;
+
+ rwlock_init(&ei->i_meta_lock);
+#ifdef CONFIG_EXT2_FS_XATTR
+ init_rwsem(&ei->xattr_sem);
+#endif
+ mutex_init(&ei->truncate_mutex);
+ inode_init_once(&ei->vfs_inode);
+}
+
+static int __init init_inodecache(void)
+{
+ ext2_inode_cachep = kmem_cache_create("ext2_inode_cache",
+ sizeof(struct ext2_inode_info),
+ 0, (SLAB_RECLAIM_ACCOUNT|
+ SLAB_MEM_SPREAD),
+ init_once);
+ if (ext2_inode_cachep == NULL)
+ return -ENOMEM;
+ return 0;
+}
+
+static void destroy_inodecache(void)
+{
+ /*
+ * Make sure all delayed rcu free inodes are flushed before we
+ * destroy cache.
+ */
+ rcu_barrier();
+ kmem_cache_destroy(ext2_inode_cachep);
+}
+
+static int ext2_show_options(struct seq_file *seq, struct dentry *root)
+{
+ struct super_block *sb = root->d_sb;
+ struct ext2_sb_info *sbi = EXT2_SB(sb);
+ struct ext2_super_block *es = sbi->s_es;
+ unsigned long def_mount_opts;
+
+ spin_lock(&sbi->s_lock);
+ def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
+
+ if (sbi->s_sb_block != 1)
+ seq_printf(seq, ",sb=%lu", sbi->s_sb_block);
+ if (test_opt(sb, MINIX_DF))
+ seq_puts(seq, ",minixdf");
+ if (test_opt(sb, GRPID))
+ seq_puts(seq, ",grpid");
+ if (!test_opt(sb, GRPID) && (def_mount_opts & EXT2_DEFM_BSDGROUPS))
+ seq_puts(seq, ",nogrpid");
+ if (!uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT2_DEF_RESUID)) ||
+ le16_to_cpu(es->s_def_resuid) != EXT2_DEF_RESUID) {
+ seq_printf(seq, ",resuid=%u",
+ from_kuid_munged(&init_user_ns, sbi->s_resuid));
+ }
+ if (!gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT2_DEF_RESGID)) ||
+ le16_to_cpu(es->s_def_resgid) != EXT2_DEF_RESGID) {
+ seq_printf(seq, ",resgid=%u",
+ from_kgid_munged(&init_user_ns, sbi->s_resgid));
+ }
+ if (test_opt(sb, ERRORS_RO)) {
+ int def_errors = le16_to_cpu(es->s_errors);
+
+ if (def_errors == EXT2_ERRORS_PANIC ||
+ def_errors == EXT2_ERRORS_CONTINUE) {
+ seq_puts(seq, ",errors=remount-ro");
+ }
+ }
+ if (test_opt(sb, ERRORS_CONT))
+ seq_puts(seq, ",errors=continue");
+ if (test_opt(sb, ERRORS_PANIC))
+ seq_puts(seq, ",errors=panic");
+ if (test_opt(sb, NO_UID32))
+ seq_puts(seq, ",nouid32");
+ if (test_opt(sb, DEBUG))
+ seq_puts(seq, ",debug");
+ if (test_opt(sb, OLDALLOC))
+ seq_puts(seq, ",oldalloc");
+
+#ifdef CONFIG_EXT2_FS_XATTR
+ if (test_opt(sb, XATTR_USER))
+ seq_puts(seq, ",user_xattr");
+ if (!test_opt(sb, XATTR_USER) &&
+ (def_mount_opts & EXT2_DEFM_XATTR_USER)) {
+ seq_puts(seq, ",nouser_xattr");
+ }
+#endif
+
+#ifdef CONFIG_EXT2_FS_POSIX_ACL
+ if (test_opt(sb, POSIX_ACL))
+ seq_puts(seq, ",acl");
+ if (!test_opt(sb, POSIX_ACL) && (def_mount_opts & EXT2_DEFM_ACL))
+ seq_puts(seq, ",noacl");
+#endif
+
+ if (test_opt(sb, NOBH))
+ seq_puts(seq, ",nobh");
+
+#if defined(CONFIG_QUOTA)
+ if (sbi->s_mount_opt & EXT2_MOUNT_USRQUOTA)
+ seq_puts(seq, ",usrquota");
+
+ if (sbi->s_mount_opt & EXT2_MOUNT_GRPQUOTA)
+ seq_puts(seq, ",grpquota");
+#endif
+
+#ifdef CONFIG_FS_DAX
+ if (sbi->s_mount_opt & EXT2_MOUNT_XIP)
+ seq_puts(seq, ",xip");
+ if (sbi->s_mount_opt & EXT2_MOUNT_DAX)
+ seq_puts(seq, ",dax");
+#endif
+
+ if (!test_opt(sb, RESERVATION))
+ seq_puts(seq, ",noreservation");
+
+ spin_unlock(&sbi->s_lock);
+ return 0;
+}
+
+#ifdef CONFIG_QUOTA
+static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, size_t len, loff_t off);
+static ssize_t ext2_quota_write(struct super_block *sb, int type, const char *data, size_t len, loff_t off);
+static struct dquot **ext2_get_dquots(struct inode *inode)
+{
+ return EXT2_I(inode)->i_dquot;
+}
+#endif
+
+static const struct super_operations ext2_sops = {
+ .alloc_inode = ext2_alloc_inode,
+ .destroy_inode = ext2_destroy_inode,
+ .write_inode = ext2_write_inode,
+ .evict_inode = ext2_evict_inode,
+ .put_super = ext2_put_super,
+ .sync_fs = ext2_sync_fs,
+ .freeze_fs = ext2_freeze,
+ .unfreeze_fs = ext2_unfreeze,
+ .statfs = ext2_statfs,
+ .remount_fs = ext2_remount,
+ .show_options = ext2_show_options,
+#ifdef CONFIG_QUOTA
+ .quota_read = ext2_quota_read,
+ .quota_write = ext2_quota_write,
+ .get_dquots = ext2_get_dquots,
+#endif
+};
+
+static struct inode *ext2_nfs_get_inode(struct super_block *sb,
+ u64 ino, u32 generation)
+{
+ struct inode *inode;
+
+ if (ino < EXT2_FIRST_INO(sb) && ino != EXT2_ROOT_INO)
+ return ERR_PTR(-ESTALE);
+ if (ino > le32_to_cpu(EXT2_SB(sb)->s_es->s_inodes_count))
+ return ERR_PTR(-ESTALE);
+
+ /*
+ * ext2_iget isn't quite right if the inode is currently unallocated!
+ * However ext2_iget currently does appropriate checks to handle stale
+ * inodes so everything is OK.
+ */
+ inode = ext2_iget(sb, ino);
+ if (IS_ERR(inode))
+ return ERR_CAST(inode);
+ if (generation && inode->i_generation != generation) {
+ /* we didn't find the right inode.. */
+ iput(inode);
+ return ERR_PTR(-ESTALE);
+ }
+ return inode;
+}
+
+static struct dentry *ext2_fh_to_dentry(struct super_block *sb, struct fid *fid,
+ int fh_len, int fh_type)
+{
+ return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
+ ext2_nfs_get_inode);
+}
+
+static struct dentry *ext2_fh_to_parent(struct super_block *sb, struct fid *fid,
+ int fh_len, int fh_type)
+{
+ return generic_fh_to_parent(sb, fid, fh_len, fh_type,
+ ext2_nfs_get_inode);
+}
+
+static const struct export_operations ext2_export_ops = {
+ .fh_to_dentry = ext2_fh_to_dentry,
+ .fh_to_parent = ext2_fh_to_parent,
+ .get_parent = ext2_get_parent,
+};
+
+static unsigned long get_sb_block(void **data)
+{
+ unsigned long sb_block;
+ char *options = (char *) *data;
+
+ if (!options || strncmp(options, "sb=", 3) != 0)
+ return 1; /* Default location */
+ options += 3;
+ sb_block = simple_strtoul(options, &options, 0);
+ if (*options && *options != ',') {
+ printk("EXT2-fs: Invalid sb specification: %s\n",
+ (char *) *data);
+ return 1;
+ }
+ if (*options == ',')
+ options++;
+ *data = (void *) options;
+ return sb_block;
+}
+
+enum {
+ Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
+ Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic,
+ Opt_err_ro, Opt_nouid32, Opt_nocheck, Opt_debug,
+ Opt_oldalloc, Opt_orlov, Opt_nobh, Opt_user_xattr, Opt_nouser_xattr,
+ Opt_acl, Opt_noacl, Opt_xip, Opt_dax, Opt_ignore, Opt_err, Opt_quota,
+ Opt_usrquota, Opt_grpquota, Opt_reservation, Opt_noreservation
+};
+
+static const match_table_t tokens = {
+ {Opt_bsd_df, "bsddf"},
+ {Opt_minix_df, "minixdf"},
+ {Opt_grpid, "grpid"},
+ {Opt_grpid, "bsdgroups"},
+ {Opt_nogrpid, "nogrpid"},
+ {Opt_nogrpid, "sysvgroups"},
+ {Opt_resgid, "resgid=%u"},
+ {Opt_resuid, "resuid=%u"},
+ {Opt_sb, "sb=%u"},
+ {Opt_err_cont, "errors=continue"},
+ {Opt_err_panic, "errors=panic"},
+ {Opt_err_ro, "errors=remount-ro"},
+ {Opt_nouid32, "nouid32"},
+ {Opt_nocheck, "check=none"},
+ {Opt_nocheck, "nocheck"},
+ {Opt_debug, "debug"},
+ {Opt_oldalloc, "oldalloc"},
+ {Opt_orlov, "orlov"},
+ {Opt_nobh, "nobh"},
+ {Opt_user_xattr, "user_xattr"},
+ {Opt_nouser_xattr, "nouser_xattr"},
+ {Opt_acl, "acl"},
+ {Opt_noacl, "noacl"},
+ {Opt_xip, "xip"},
+ {Opt_dax, "dax"},
+ {Opt_grpquota, "grpquota"},
+ {Opt_ignore, "noquota"},
+ {Opt_quota, "quota"},
+ {Opt_usrquota, "usrquota"},
+ {Opt_reservation, "reservation"},
+ {Opt_noreservation, "noreservation"},
+ {Opt_err, NULL}
+};
+
+static int parse_options(char *options, struct super_block *sb)
+{
+ char *p;
+ struct ext2_sb_info *sbi = EXT2_SB(sb);
+ substring_t args[MAX_OPT_ARGS];
+ int option;
+ kuid_t uid;
+ kgid_t gid;
+
+ if (!options)
+ return 1;
+
+ while ((p = strsep (&options, ",")) != NULL) {
+ int token;
+ if (!*p)
+ continue;
+
+ token = match_token(p, tokens, args);
+ switch (token) {
+ case Opt_bsd_df:
+ clear_opt (sbi->s_mount_opt, MINIX_DF);
+ break;
+ case Opt_minix_df:
+ set_opt (sbi->s_mount_opt, MINIX_DF);
+ break;
+ case Opt_grpid:
+ set_opt (sbi->s_mount_opt, GRPID);
+ break;
+ case Opt_nogrpid:
+ clear_opt (sbi->s_mount_opt, GRPID);
+ break;
+ case Opt_resuid:
+ if (match_int(&args[0], &option))
+ return 0;
+ uid = make_kuid(current_user_ns(), option);
+ if (!uid_valid(uid)) {
+ ext2_msg(sb, KERN_ERR, "Invalid uid value %d", option);
+ return 0;
+
+ }
+ sbi->s_resuid = uid;
+ break;
+ case Opt_resgid:
+ if (match_int(&args[0], &option))
+ return 0;
+ gid = make_kgid(current_user_ns(), option);
+ if (!gid_valid(gid)) {
+ ext2_msg(sb, KERN_ERR, "Invalid gid value %d", option);
+ return 0;
+ }
+ sbi->s_resgid = gid;
+ break;
+ case Opt_sb:
+ /* handled by get_sb_block() instead of here */
+ /* *sb_block = match_int(&args[0]); */
+ break;
+ case Opt_err_panic:
+ clear_opt (sbi->s_mount_opt, ERRORS_CONT);
+ clear_opt (sbi->s_mount_opt, ERRORS_RO);
+ set_opt (sbi->s_mount_opt, ERRORS_PANIC);
+ break;
+ case Opt_err_ro:
+ clear_opt (sbi->s_mount_opt, ERRORS_CONT);
+ clear_opt (sbi->s_mount_opt, ERRORS_PANIC);
+ set_opt (sbi->s_mount_opt, ERRORS_RO);
+ break;
+ case Opt_err_cont:
+ clear_opt (sbi->s_mount_opt, ERRORS_RO);
+ clear_opt (sbi->s_mount_opt, ERRORS_PANIC);
+ set_opt (sbi->s_mount_opt, ERRORS_CONT);
+ break;
+ case Opt_nouid32:
+ set_opt (sbi->s_mount_opt, NO_UID32);
+ break;
+ case Opt_nocheck:
+ clear_opt (sbi->s_mount_opt, CHECK);
+ break;
+ case Opt_debug:
+ set_opt (sbi->s_mount_opt, DEBUG);
+ break;
+ case Opt_oldalloc:
+ set_opt (sbi->s_mount_opt, OLDALLOC);
+ break;
+ case Opt_orlov:
+ clear_opt (sbi->s_mount_opt, OLDALLOC);
+ break;
+ case Opt_nobh:
+ set_opt (sbi->s_mount_opt, NOBH);
+ break;
+#ifdef CONFIG_EXT2_FS_XATTR
+ case Opt_user_xattr:
+ set_opt (sbi->s_mount_opt, XATTR_USER);
+ break;
+ case Opt_nouser_xattr:
+ clear_opt (sbi->s_mount_opt, XATTR_USER);
+ break;
+#else
+ case Opt_user_xattr:
+ case Opt_nouser_xattr:
+ ext2_msg(sb, KERN_INFO, "(no)user_xattr options"
+ "not supported");
+ break;
+#endif
+#ifdef CONFIG_EXT2_FS_POSIX_ACL
+ case Opt_acl:
+ set_opt(sbi->s_mount_opt, POSIX_ACL);
+ break;
+ case Opt_noacl:
+ clear_opt(sbi->s_mount_opt, POSIX_ACL);
+ break;
+#else
+ case Opt_acl:
+ case Opt_noacl:
+ ext2_msg(sb, KERN_INFO,
+ "(no)acl options not supported");
+ break;
+#endif
+ case Opt_xip:
+ ext2_msg(sb, KERN_INFO, "use dax instead of xip");
+ set_opt(sbi->s_mount_opt, XIP);
+ /* Fall through */
+ case Opt_dax:
+#ifdef CONFIG_FS_DAX
+ set_opt(sbi->s_mount_opt, DAX);
+#else
+ ext2_msg(sb, KERN_INFO, "dax option not supported");
+#endif
+ break;
+
+#if defined(CONFIG_QUOTA)
+ case Opt_quota:
+ case Opt_usrquota:
+ set_opt(sbi->s_mount_opt, USRQUOTA);
+ break;
+
+ case Opt_grpquota:
+ set_opt(sbi->s_mount_opt, GRPQUOTA);
+ break;
+#else
+ case Opt_quota:
+ case Opt_usrquota:
+ case Opt_grpquota:
+ ext2_msg(sb, KERN_INFO,
+ "quota operations not supported");
+ break;
+#endif
+
+ case Opt_reservation:
+ set_opt(sbi->s_mount_opt, RESERVATION);
+ ext2_msg(sb, KERN_INFO, "reservations ON");
+ break;
+ case Opt_noreservation:
+ clear_opt(sbi->s_mount_opt, RESERVATION);
+ ext2_msg(sb, KERN_INFO, "reservations OFF");
+ break;
+ case Opt_ignore:
+ break;
+ default:
+ return 0;
+ }
+ }
+ return 1;
+}
+
+static int ext2_setup_super (struct super_block * sb,
+ struct ext2_super_block * es,
+ int read_only)
+{
+ int res = 0;
+ struct ext2_sb_info *sbi = EXT2_SB(sb);
+
+ if (le32_to_cpu(es->s_rev_level) > EXT2_MAX_SUPP_REV) {
+ ext2_msg(sb, KERN_ERR,
+ "error: revision level too high, "
+ "forcing read-only mode");
+ res = MS_RDONLY;
+ }
+ if (read_only)
+ return res;
+ if (!(sbi->s_mount_state & EXT2_VALID_FS))
+ ext2_msg(sb, KERN_WARNING,
+ "warning: mounting unchecked fs, "
+ "running e2fsck is recommended");
+ else if ((sbi->s_mount_state & EXT2_ERROR_FS))
+ ext2_msg(sb, KERN_WARNING,
+ "warning: mounting fs with errors, "
+ "running e2fsck is recommended");
+ else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 &&
+ le16_to_cpu(es->s_mnt_count) >=
+ (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
+ ext2_msg(sb, KERN_WARNING,
+ "warning: maximal mount count reached, "
+ "running e2fsck is recommended");
+ else if (le32_to_cpu(es->s_checkinterval) &&
+ (le32_to_cpu(es->s_lastcheck) +
+ le32_to_cpu(es->s_checkinterval) <= get_seconds()))
+ ext2_msg(sb, KERN_WARNING,
+ "warning: checktime reached, "
+ "running e2fsck is recommended");
+ if (!le16_to_cpu(es->s_max_mnt_count))
+ es->s_max_mnt_count = cpu_to_le16(EXT2_DFL_MAX_MNT_COUNT);
+ le16_add_cpu(&es->s_mnt_count, 1);
+ if (test_opt (sb, DEBUG))
+ ext2_msg(sb, KERN_INFO, "%s, %s, bs=%lu, fs=%lu, gc=%lu, "
+ "bpg=%lu, ipg=%lu, mo=%04lx]",
+ EXT2FS_VERSION, EXT2FS_DATE, sb->s_blocksize,
+ sbi->s_frag_size,
+ sbi->s_groups_count,
+ EXT2_BLOCKS_PER_GROUP(sb),
+ EXT2_INODES_PER_GROUP(sb),
+ sbi->s_mount_opt);
+ return res;
+}
+
+static int ext2_check_descriptors(struct super_block *sb)
+{
+ int i;
+ struct ext2_sb_info *sbi = EXT2_SB(sb);
+
+ ext2_debug ("Checking group descriptors");
+
+ for (i = 0; i < sbi->s_groups_count; i++) {
+ struct ext2_group_desc *gdp = ext2_get_group_desc(sb, i, NULL);
+ ext2_fsblk_t first_block = ext2_group_first_block_no(sb, i);
+ ext2_fsblk_t last_block;
+
+ if (i == sbi->s_groups_count - 1)
+ last_block = le32_to_cpu(sbi->s_es->s_blocks_count) - 1;
+ else
+ last_block = first_block +
+ (EXT2_BLOCKS_PER_GROUP(sb) - 1);
+
+ if (le32_to_cpu(gdp->bg_block_bitmap) < first_block ||
+ le32_to_cpu(gdp->bg_block_bitmap) > last_block)
+ {
+ ext2_error (sb, "ext2_check_descriptors",
+ "Block bitmap for group %d"
+ " not in group (block %lu)!",
+ i, (unsigned long) le32_to_cpu(gdp->bg_block_bitmap));
+ return 0;
+ }
+ if (le32_to_cpu(gdp->bg_inode_bitmap) < first_block ||
+ le32_to_cpu(gdp->bg_inode_bitmap) > last_block)
+ {
+ ext2_error (sb, "ext2_check_descriptors",
+ "Inode bitmap for group %d"
+ " not in group (block %lu)!",
+ i, (unsigned long) le32_to_cpu(gdp->bg_inode_bitmap));
+ return 0;
+ }
+ if (le32_to_cpu(gdp->bg_inode_table) < first_block ||
+ le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group - 1 >
+ last_block)
+ {
+ ext2_error (sb, "ext2_check_descriptors",
+ "Inode table for group %d"
+ " not in group (block %lu)!",
+ i, (unsigned long) le32_to_cpu(gdp->bg_inode_table));
+ return 0;
+ }
+ }
+ return 1;
+}
+
+/*
+ * Maximal file size. There is a direct, and {,double-,triple-}indirect
+ * block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks.
+ * We need to be 1 filesystem block less than the 2^32 sector limit.
+ */
+static loff_t ext2_max_size(int bits)
+{
+ loff_t res = EXT2_NDIR_BLOCKS;
+ int meta_blocks;
+ loff_t upper_limit;
+
+ /* This is calculated to be the largest file size for a
+ * dense, file such that the total number of
+ * sectors in the file, including data and all indirect blocks,
+ * does not exceed 2^32 -1
+ * __u32 i_blocks representing the total number of
+ * 512 bytes blocks of the file
+ */
+ upper_limit = (1LL << 32) - 1;
+
+ /* total blocks in file system block size */
+ upper_limit >>= (bits - 9);
+
+
+ /* indirect blocks */
+ meta_blocks = 1;
+ /* double indirect blocks */
+ meta_blocks += 1 + (1LL << (bits-2));
+ /* tripple indirect blocks */
+ meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
+
+ upper_limit -= meta_blocks;
+ upper_limit <<= bits;
+
+ res += 1LL << (bits-2);
+ res += 1LL << (2*(bits-2));
+ res += 1LL << (3*(bits-2));
+ res <<= bits;
+ if (res > upper_limit)
+ res = upper_limit;
+
+ if (res > MAX_LFS_FILESIZE)
+ res = MAX_LFS_FILESIZE;
+
+ return res;
+}
+
+static unsigned long descriptor_loc(struct super_block *sb,
+ unsigned long logic_sb_block,
+ int nr)
+{
+ struct ext2_sb_info *sbi = EXT2_SB(sb);
+ unsigned long bg, first_meta_bg;
+ int has_super = 0;
+
+ first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
+
+ if (!EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_META_BG) ||
+ nr < first_meta_bg)
+ return (logic_sb_block + nr + 1);
+ bg = sbi->s_desc_per_block * nr;
+ if (ext2_bg_has_super(sb, bg))
+ has_super = 1;
+
+ return ext2_group_first_block_no(sb, bg) + has_super;
+}
+
+static int ext2_fill_super(struct super_block *sb, void *data, int silent)
+{
+ struct buffer_head * bh;
+ struct ext2_sb_info * sbi;
+ struct ext2_super_block * es;
+ struct inode *root;
+ unsigned long block;
+ unsigned long sb_block = get_sb_block(&data);
+ unsigned long logic_sb_block;
+ unsigned long offset = 0;
+ unsigned long def_mount_opts;
+ long ret = -EINVAL;
+ int blocksize = BLOCK_SIZE;
+ int db_count;
+ int i, j;
+ __le32 features;
+ int err;
+
+ err = -ENOMEM;
+ sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
+ if (!sbi)
+ goto failed;
+
+ sbi->s_blockgroup_lock =
+ kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
+ if (!sbi->s_blockgroup_lock) {
+ kfree(sbi);
+ goto failed;
+ }
+ sb->s_fs_info = sbi;
+ sbi->s_sb_block = sb_block;
+
+ spin_lock_init(&sbi->s_lock);
+
+ /*
+ * See what the current blocksize for the device is, and
+ * use that as the blocksize. Otherwise (or if the blocksize
+ * is smaller than the default) use the default.
+ * This is important for devices that have a hardware
+ * sectorsize that is larger than the default.
+ */
+ blocksize = sb_min_blocksize(sb, BLOCK_SIZE);
+ if (!blocksize) {
+ ext2_msg(sb, KERN_ERR, "error: unable to set blocksize");
+ goto failed_sbi;
+ }
+
+ /*
+ * If the superblock doesn't start on a hardware sector boundary,
+ * calculate the offset.
+ */
+ if (blocksize != BLOCK_SIZE) {
+ logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
+ offset = (sb_block*BLOCK_SIZE) % blocksize;
+ } else {
+ logic_sb_block = sb_block;
+ }
+
+ if (!(bh = sb_bread(sb, logic_sb_block))) {
+ ext2_msg(sb, KERN_ERR, "error: unable to read superblock");
+ goto failed_sbi;
+ }
+ /*
+ * Note: s_es must be initialized as soon as possible because
+ * some ext2 macro-instructions depend on its value
+ */
+ es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
+ sbi->s_es = es;
+ sb->s_magic = le16_to_cpu(es->s_magic);
+
+ if (sb->s_magic != EXT2_SUPER_MAGIC)
+ goto cantfind_ext2;
+
+ /* Set defaults before we parse the mount options */
+ def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
+ if (def_mount_opts & EXT2_DEFM_DEBUG)
+ set_opt(sbi->s_mount_opt, DEBUG);
+ if (def_mount_opts & EXT2_DEFM_BSDGROUPS)
+ set_opt(sbi->s_mount_opt, GRPID);
+ if (def_mount_opts & EXT2_DEFM_UID16)
+ set_opt(sbi->s_mount_opt, NO_UID32);
+#ifdef CONFIG_EXT2_FS_XATTR
+ if (def_mount_opts & EXT2_DEFM_XATTR_USER)
+ set_opt(sbi->s_mount_opt, XATTR_USER);
+#endif
+#ifdef CONFIG_EXT2_FS_POSIX_ACL
+ if (def_mount_opts & EXT2_DEFM_ACL)
+ set_opt(sbi->s_mount_opt, POSIX_ACL);
+#endif
+
+ if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_PANIC)
+ set_opt(sbi->s_mount_opt, ERRORS_PANIC);
+ else if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_CONTINUE)
+ set_opt(sbi->s_mount_opt, ERRORS_CONT);
+ else
+ set_opt(sbi->s_mount_opt, ERRORS_RO);
+
+ sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
+ sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
+
+ set_opt(sbi->s_mount_opt, RESERVATION);
+
+ if (!parse_options((char *) data, sb))
+ goto failed_mount;
+
+ sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
+ ((EXT2_SB(sb)->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ?
+ MS_POSIXACL : 0);
+
+ if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV &&
+ (EXT2_HAS_COMPAT_FEATURE(sb, ~0U) ||
+ EXT2_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
+ EXT2_HAS_INCOMPAT_FEATURE(sb, ~0U)))
+ ext2_msg(sb, KERN_WARNING,
+ "warning: feature flags set on rev 0 fs, "
+ "running e2fsck is recommended");
+ /*
+ * Check feature flags regardless of the revision level, since we
+ * previously didn't change the revision level when setting the flags,
+ * so there is a chance incompat flags are set on a rev 0 filesystem.
+ */
+ features = EXT2_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP);
+ if (features) {
+ ext2_msg(sb, KERN_ERR, "error: couldn't mount because of "
+ "unsupported optional features (%x)",
+ le32_to_cpu(features));
+ goto failed_mount;
+ }
+ if (!(sb->s_flags & MS_RDONLY) &&
+ (features = EXT2_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))){
+ ext2_msg(sb, KERN_ERR, "error: couldn't mount RDWR because of "
+ "unsupported optional features (%x)",
+ le32_to_cpu(features));
+ goto failed_mount;
+ }
+
+ blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
+
+ if (sbi->s_mount_opt & EXT2_MOUNT_DAX) {
+ if (blocksize != PAGE_SIZE) {
+ ext2_msg(sb, KERN_ERR,
+ "error: unsupported blocksize for dax");
+ goto failed_mount;
+ }
+ if (!sb->s_bdev->bd_disk->fops->direct_access) {
+ ext2_msg(sb, KERN_ERR,
+ "error: device does not support dax");
+ goto failed_mount;
+ }
+ }
+
+ /* If the blocksize doesn't match, re-read the thing.. */
+ if (sb->s_blocksize != blocksize) {
+ brelse(bh);
+
+ if (!sb_set_blocksize(sb, blocksize)) {
+ ext2_msg(sb, KERN_ERR,
+ "error: bad blocksize %d", blocksize);
+ goto failed_sbi;
+ }
+
+ logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
+ offset = (sb_block*BLOCK_SIZE) % blocksize;
+ bh = sb_bread(sb, logic_sb_block);
+ if(!bh) {
+ ext2_msg(sb, KERN_ERR, "error: couldn't read"
+ "superblock on 2nd try");
+ goto failed_sbi;
+ }
+ es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
+ sbi->s_es = es;
+ if (es->s_magic != cpu_to_le16(EXT2_SUPER_MAGIC)) {
+ ext2_msg(sb, KERN_ERR, "error: magic mismatch");
+ goto failed_mount;
+ }
+ }
+
+ sb->s_maxbytes = ext2_max_size(sb->s_blocksize_bits);
+ sb->s_max_links = EXT2_LINK_MAX;
+
+ if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV) {
+ sbi->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE;
+ sbi->s_first_ino = EXT2_GOOD_OLD_FIRST_INO;
+ } else {
+ sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
+ sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
+ if ((sbi->s_inode_size < EXT2_GOOD_OLD_INODE_SIZE) ||
+ !is_power_of_2(sbi->s_inode_size) ||
+ (sbi->s_inode_size > blocksize)) {
+ ext2_msg(sb, KERN_ERR,
+ "error: unsupported inode size: %d",
+ sbi->s_inode_size);
+ goto failed_mount;
+ }
+ }
+
+ sbi->s_frag_size = EXT2_MIN_FRAG_SIZE <<
+ le32_to_cpu(es->s_log_frag_size);
+ if (sbi->s_frag_size == 0)
+ goto cantfind_ext2;
+ sbi->s_frags_per_block = sb->s_blocksize / sbi->s_frag_size;
+
+ sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
+ sbi->s_frags_per_group = le32_to_cpu(es->s_frags_per_group);
+ sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
+
+ if (EXT2_INODE_SIZE(sb) == 0)
+ goto cantfind_ext2;
+ sbi->s_inodes_per_block = sb->s_blocksize / EXT2_INODE_SIZE(sb);
+ if (sbi->s_inodes_per_block == 0 || sbi->s_inodes_per_group == 0)
+ goto cantfind_ext2;
+ sbi->s_itb_per_group = sbi->s_inodes_per_group /
+ sbi->s_inodes_per_block;
+ sbi->s_desc_per_block = sb->s_blocksize /
+ sizeof (struct ext2_group_desc);
+ sbi->s_sbh = bh;
+ sbi->s_mount_state = le16_to_cpu(es->s_state);
+ sbi->s_addr_per_block_bits =
+ ilog2 (EXT2_ADDR_PER_BLOCK(sb));
+ sbi->s_desc_per_block_bits =
+ ilog2 (EXT2_DESC_PER_BLOCK(sb));
+
+ if (sb->s_magic != EXT2_SUPER_MAGIC)
+ goto cantfind_ext2;
+
+ if (sb->s_blocksize != bh->b_size) {
+ if (!silent)
+ ext2_msg(sb, KERN_ERR, "error: unsupported blocksize");
+ goto failed_mount;
+ }
+
+ if (sb->s_blocksize != sbi->s_frag_size) {
+ ext2_msg(sb, KERN_ERR,
+ "error: fragsize %lu != blocksize %lu"
+ "(not supported yet)",
+ sbi->s_frag_size, sb->s_blocksize);
+ goto failed_mount;
+ }
+
+ if (sbi->s_blocks_per_group > sb->s_blocksize * 8) {
+ ext2_msg(sb, KERN_ERR,
+ "error: #blocks per group too big: %lu",
+ sbi->s_blocks_per_group);
+ goto failed_mount;
+ }
+ if (sbi->s_frags_per_group > sb->s_blocksize * 8) {
+ ext2_msg(sb, KERN_ERR,
+ "error: #fragments per group too big: %lu",
+ sbi->s_frags_per_group);
+ goto failed_mount;
+ }
+ if (sbi->s_inodes_per_group > sb->s_blocksize * 8) {
+ ext2_msg(sb, KERN_ERR,
+ "error: #inodes per group too big: %lu",
+ sbi->s_inodes_per_group);
+ goto failed_mount;
+ }
+
+ if (EXT2_BLOCKS_PER_GROUP(sb) == 0)
+ goto cantfind_ext2;
+ sbi->s_groups_count = ((le32_to_cpu(es->s_blocks_count) -
+ le32_to_cpu(es->s_first_data_block) - 1)
+ / EXT2_BLOCKS_PER_GROUP(sb)) + 1;
+ db_count = (sbi->s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) /
+ EXT2_DESC_PER_BLOCK(sb);
+ sbi->s_group_desc = kmalloc (db_count * sizeof (struct buffer_head *), GFP_KERNEL);
+ if (sbi->s_group_desc == NULL) {
+ ext2_msg(sb, KERN_ERR, "error: not enough memory");
+ goto failed_mount;
+ }
+ bgl_lock_init(sbi->s_blockgroup_lock);
+ sbi->s_debts = kcalloc(sbi->s_groups_count, sizeof(*sbi->s_debts), GFP_KERNEL);
+ if (!sbi->s_debts) {
+ ext2_msg(sb, KERN_ERR, "error: not enough memory");
+ goto failed_mount_group_desc;
+ }
+ for (i = 0; i < db_count; i++) {
+ block = descriptor_loc(sb, logic_sb_block, i);
+ sbi->s_group_desc[i] = sb_bread(sb, block);
+ if (!sbi->s_group_desc[i]) {
+ for (j = 0; j < i; j++)
+ brelse (sbi->s_group_desc[j]);
+ ext2_msg(sb, KERN_ERR,
+ "error: unable to read group descriptors");
+ goto failed_mount_group_desc;
+ }
+ }
+ if (!ext2_check_descriptors (sb)) {
+ ext2_msg(sb, KERN_ERR, "group descriptors corrupted");
+ goto failed_mount2;
+ }
+ sbi->s_gdb_count = db_count;
+ get_random_bytes(&sbi->s_next_generation, sizeof(u32));
+ spin_lock_init(&sbi->s_next_gen_lock);
+
+ /* per fileystem reservation list head & lock */
+ spin_lock_init(&sbi->s_rsv_window_lock);
+ sbi->s_rsv_window_root = RB_ROOT;
+ /*
+ * Add a single, static dummy reservation to the start of the
+ * reservation window list --- it gives us a placeholder for
+ * append-at-start-of-list which makes the allocation logic
+ * _much_ simpler.
+ */
+ sbi->s_rsv_window_head.rsv_start = EXT2_RESERVE_WINDOW_NOT_ALLOCATED;
+ sbi->s_rsv_window_head.rsv_end = EXT2_RESERVE_WINDOW_NOT_ALLOCATED;
+ sbi->s_rsv_window_head.rsv_alloc_hit = 0;
+ sbi->s_rsv_window_head.rsv_goal_size = 0;
+ ext2_rsv_window_add(sb, &sbi->s_rsv_window_head);
+
+ err = percpu_counter_init(&sbi->s_freeblocks_counter,
+ ext2_count_free_blocks(sb), GFP_KERNEL);
+ if (!err) {
+ err = percpu_counter_init(&sbi->s_freeinodes_counter,
+ ext2_count_free_inodes(sb), GFP_KERNEL);
+ }
+ if (!err) {
+ err = percpu_counter_init(&sbi->s_dirs_counter,
+ ext2_count_dirs(sb), GFP_KERNEL);
+ }
+ if (err) {
+ ext2_msg(sb, KERN_ERR, "error: insufficient memory");
+ goto failed_mount3;
+ }
+ /*
+ * set up enough so that it can read an inode
+ */
+ sb->s_op = &ext2_sops;
+ sb->s_export_op = &ext2_export_ops;
+ sb->s_xattr = ext2_xattr_handlers;
+
+#ifdef CONFIG_QUOTA
+ sb->dq_op = &dquot_operations;
+ sb->s_qcop = &dquot_quotactl_ops;
+ sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP;
+#endif
+
+ root = ext2_iget(sb, EXT2_ROOT_INO);
+ if (IS_ERR(root)) {
+ ret = PTR_ERR(root);
+ goto failed_mount3;
+ }
+ if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
+ iput(root);
+ ext2_msg(sb, KERN_ERR, "error: corrupt root inode, run e2fsck");
+ goto failed_mount3;
+ }
+
+ sb->s_root = d_make_root(root);
+ if (!sb->s_root) {
+ ext2_msg(sb, KERN_ERR, "error: get root inode failed");
+ ret = -ENOMEM;
+ goto failed_mount3;
+ }
+ if (EXT2_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_HAS_JOURNAL))
+ ext2_msg(sb, KERN_WARNING,
+ "warning: mounting ext3 filesystem as ext2");
+ if (ext2_setup_super (sb, es, sb->s_flags & MS_RDONLY))
+ sb->s_flags |= MS_RDONLY;
+ ext2_write_super(sb);
+ return 0;
+
+cantfind_ext2:
+ if (!silent)
+ ext2_msg(sb, KERN_ERR,
+ "error: can't find an ext2 filesystem on dev %s.",
+ sb->s_id);
+ goto failed_mount;
+failed_mount3:
+ percpu_counter_destroy(&sbi->s_freeblocks_counter);
+ percpu_counter_destroy(&sbi->s_freeinodes_counter);
+ percpu_counter_destroy(&sbi->s_dirs_counter);
+failed_mount2:
+ for (i = 0; i < db_count; i++)
+ brelse(sbi->s_group_desc[i]);
+failed_mount_group_desc:
+ kfree(sbi->s_group_desc);
+ kfree(sbi->s_debts);
+failed_mount:
+ brelse(bh);
+failed_sbi:
+ sb->s_fs_info = NULL;
+ kfree(sbi->s_blockgroup_lock);
+ kfree(sbi);
+failed:
+ return ret;
+}
+
+static void ext2_clear_super_error(struct super_block *sb)
+{
+ struct buffer_head *sbh = EXT2_SB(sb)->s_sbh;
+
+ if (buffer_write_io_error(sbh)) {
+ /*
+ * Oh, dear. A previous attempt to write the
+ * superblock failed. This could happen because the
+ * USB device was yanked out. Or it could happen to
+ * be a transient write error and maybe the block will
+ * be remapped. Nothing we can do but to retry the
+ * write and hope for the best.
+ */
+ ext2_msg(sb, KERN_ERR,
+ "previous I/O error to superblock detected\n");
+ clear_buffer_write_io_error(sbh);
+ set_buffer_uptodate(sbh);
+ }
+}
+
+static void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es,
+ int wait)
+{
+ ext2_clear_super_error(sb);
+ spin_lock(&EXT2_SB(sb)->s_lock);
+ es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb));
+ es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb));
+ es->s_wtime = cpu_to_le32(get_seconds());
+ /* unlock before we do IO */
+ spin_unlock(&EXT2_SB(sb)->s_lock);
+ mark_buffer_dirty(EXT2_SB(sb)->s_sbh);
+ if (wait)
+ sync_dirty_buffer(EXT2_SB(sb)->s_sbh);
+}
+
+/*
+ * In the second extended file system, it is not necessary to
+ * write the super block since we use a mapping of the
+ * disk super block in a buffer.
+ *
+ * However, this function is still used to set the fs valid
+ * flags to 0. We need to set this flag to 0 since the fs
+ * may have been checked while mounted and e2fsck may have
+ * set s_state to EXT2_VALID_FS after some corrections.
+ */
+static int ext2_sync_fs(struct super_block *sb, int wait)
+{
+ struct ext2_sb_info *sbi = EXT2_SB(sb);
+ struct ext2_super_block *es = EXT2_SB(sb)->s_es;
+
+ /*
+ * Write quota structures to quota file, sync_blockdev() will write
+ * them to disk later
+ */
+ dquot_writeback_dquots(sb, -1);
+
+ spin_lock(&sbi->s_lock);
+ if (es->s_state & cpu_to_le16(EXT2_VALID_FS)) {
+ ext2_debug("setting valid to 0\n");
+ es->s_state &= cpu_to_le16(~EXT2_VALID_FS);
+ }
+ spin_unlock(&sbi->s_lock);
+ ext2_sync_super(sb, es, wait);
+ return 0;
+}
+
+static int ext2_freeze(struct super_block *sb)
+{
+ struct ext2_sb_info *sbi = EXT2_SB(sb);
+
+ /*
+ * Open but unlinked files present? Keep EXT2_VALID_FS flag cleared
+ * because we have unattached inodes and thus filesystem is not fully
+ * consistent.
+ */
+ if (atomic_long_read(&sb->s_remove_count)) {
+ ext2_sync_fs(sb, 1);
+ return 0;
+ }
+ /* Set EXT2_FS_VALID flag */
+ spin_lock(&sbi->s_lock);
+ sbi->s_es->s_state = cpu_to_le16(sbi->s_mount_state);
+ spin_unlock(&sbi->s_lock);
+ ext2_sync_super(sb, sbi->s_es, 1);
+
+ return 0;
+}
+
+static int ext2_unfreeze(struct super_block *sb)
+{
+ /* Just write sb to clear EXT2_VALID_FS flag */
+ ext2_write_super(sb);
+
+ return 0;
+}
+
+void ext2_write_super(struct super_block *sb)
+{
+ if (!(sb->s_flags & MS_RDONLY))
+ ext2_sync_fs(sb, 1);
+}
+
+static int ext2_remount (struct super_block * sb, int * flags, char * data)
+{
+ struct ext2_sb_info * sbi = EXT2_SB(sb);
+ struct ext2_super_block * es;
+ struct ext2_mount_options old_opts;
+ unsigned long old_sb_flags;
+ int err;
+
+ sync_filesystem(sb);
+ spin_lock(&sbi->s_lock);
+
+ /* Store the old options */
+ old_sb_flags = sb->s_flags;
+ old_opts.s_mount_opt = sbi->s_mount_opt;
+ old_opts.s_resuid = sbi->s_resuid;
+ old_opts.s_resgid = sbi->s_resgid;
+
+ /*
+ * Allow the "check" option to be passed as a remount option.
+ */
+ if (!parse_options(data, sb)) {
+ err = -EINVAL;
+ goto restore_opts;
+ }
+
+ sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
+ ((sbi->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
+
+ es = sbi->s_es;
+ if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT2_MOUNT_DAX) {
+ ext2_msg(sb, KERN_WARNING, "warning: refusing change of "
+ "dax flag with busy inodes while remounting");
+ sbi->s_mount_opt ^= EXT2_MOUNT_DAX;
+ }
+ if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) {
+ spin_unlock(&sbi->s_lock);
+ return 0;
+ }
+ if (*flags & MS_RDONLY) {
+ if (le16_to_cpu(es->s_state) & EXT2_VALID_FS ||
+ !(sbi->s_mount_state & EXT2_VALID_FS)) {
+ spin_unlock(&sbi->s_lock);
+ return 0;
+ }
+
+ /*
+ * OK, we are remounting a valid rw partition rdonly, so set
+ * the rdonly flag and then mark the partition as valid again.
+ */
+ es->s_state = cpu_to_le16(sbi->s_mount_state);
+ es->s_mtime = cpu_to_le32(get_seconds());
+ spin_unlock(&sbi->s_lock);
+
+ err = dquot_suspend(sb, -1);
+ if (err < 0) {
+ spin_lock(&sbi->s_lock);
+ goto restore_opts;
+ }
+
+ ext2_sync_super(sb, es, 1);
+ } else {
+ __le32 ret = EXT2_HAS_RO_COMPAT_FEATURE(sb,
+ ~EXT2_FEATURE_RO_COMPAT_SUPP);
+ if (ret) {
+ ext2_msg(sb, KERN_WARNING,
+ "warning: couldn't remount RDWR because of "
+ "unsupported optional features (%x).",
+ le32_to_cpu(ret));
+ err = -EROFS;
+ goto restore_opts;
+ }
+ /*
+ * Mounting a RDONLY partition read-write, so reread and
+ * store the current valid flag. (It may have been changed
+ * by e2fsck since we originally mounted the partition.)
+ */
+ sbi->s_mount_state = le16_to_cpu(es->s_state);
+ if (!ext2_setup_super (sb, es, 0))
+ sb->s_flags &= ~MS_RDONLY;
+ spin_unlock(&sbi->s_lock);
+
+ ext2_write_super(sb);
+
+ dquot_resume(sb, -1);
+ }
+
+ return 0;
+restore_opts:
+ sbi->s_mount_opt = old_opts.s_mount_opt;
+ sbi->s_resuid = old_opts.s_resuid;
+ sbi->s_resgid = old_opts.s_resgid;
+ sb->s_flags = old_sb_flags;
+ spin_unlock(&sbi->s_lock);
+ return err;
+}
+
+static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf)
+{
+ struct super_block *sb = dentry->d_sb;
+ struct ext2_sb_info *sbi = EXT2_SB(sb);
+ struct ext2_super_block *es = sbi->s_es;
+ u64 fsid;
+
+ spin_lock(&sbi->s_lock);
+
+ if (test_opt (sb, MINIX_DF))
+ sbi->s_overhead_last = 0;
+ else if (sbi->s_blocks_last != le32_to_cpu(es->s_blocks_count)) {
+ unsigned long i, overhead = 0;
+ smp_rmb();
+
+ /*
+ * Compute the overhead (FS structures). This is constant
+ * for a given filesystem unless the number of block groups
+ * changes so we cache the previous value until it does.
+ */
+
+ /*
+ * All of the blocks before first_data_block are
+ * overhead
+ */
+ overhead = le32_to_cpu(es->s_first_data_block);
+
+ /*
+ * Add the overhead attributed to the superblock and
+ * block group descriptors. If the sparse superblocks
+ * feature is turned on, then not all groups have this.
+ */
+ for (i = 0; i < sbi->s_groups_count; i++)
+ overhead += ext2_bg_has_super(sb, i) +
+ ext2_bg_num_gdb(sb, i);
+
+ /*
+ * Every block group has an inode bitmap, a block
+ * bitmap, and an inode table.
+ */
+ overhead += (sbi->s_groups_count *
+ (2 + sbi->s_itb_per_group));
+ sbi->s_overhead_last = overhead;
+ smp_wmb();
+ sbi->s_blocks_last = le32_to_cpu(es->s_blocks_count);
+ }
+
+ buf->f_type = EXT2_SUPER_MAGIC;
+ buf->f_bsize = sb->s_blocksize;
+ buf->f_blocks = le32_to_cpu(es->s_blocks_count) - sbi->s_overhead_last;
+ buf->f_bfree = ext2_count_free_blocks(sb);
+ es->s_free_blocks_count = cpu_to_le32(buf->f_bfree);
+ buf->f_bavail = buf->f_bfree - le32_to_cpu(es->s_r_blocks_count);
+ if (buf->f_bfree < le32_to_cpu(es->s_r_blocks_count))
+ buf->f_bavail = 0;
+ buf->f_files = le32_to_cpu(es->s_inodes_count);
+ buf->f_ffree = ext2_count_free_inodes(sb);
+ es->s_free_inodes_count = cpu_to_le32(buf->f_ffree);
+ buf->f_namelen = EXT2_NAME_LEN;
+ fsid = le64_to_cpup((void *)es->s_uuid) ^
+ le64_to_cpup((void *)es->s_uuid + sizeof(u64));
+ buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
+ buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
+ spin_unlock(&sbi->s_lock);
+ return 0;
+}
+
+static struct dentry *ext2_mount(struct file_system_type *fs_type,
+ int flags, const char *dev_name, void *data)
+{
+ return mount_bdev(fs_type, flags, dev_name, data, ext2_fill_super);
+}
+
+#ifdef CONFIG_QUOTA
+
+/* Read data from quotafile - avoid pagecache and such because we cannot afford
+ * acquiring the locks... As quota files are never truncated and quota code
+ * itself serializes the operations (and no one else should touch the files)
+ * we don't have to be afraid of races */
+static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data,
+ size_t len, loff_t off)
+{
+ struct inode *inode = sb_dqopt(sb)->files[type];
+ sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb);
+ int err = 0;
+ int offset = off & (sb->s_blocksize - 1);
+ int tocopy;
+ size_t toread;
+ struct buffer_head tmp_bh;
+ struct buffer_head *bh;
+ loff_t i_size = i_size_read(inode);
+
+ if (off > i_size)
+ return 0;
+ if (off+len > i_size)
+ len = i_size-off;
+ toread = len;
+ while (toread > 0) {
+ tocopy = sb->s_blocksize - offset < toread ?
+ sb->s_blocksize - offset : toread;
+
+ tmp_bh.b_state = 0;
+ tmp_bh.b_size = sb->s_blocksize;
+ err = ext2_get_block(inode, blk, &tmp_bh, 0);
+ if (err < 0)
+ return err;
+ if (!buffer_mapped(&tmp_bh)) /* A hole? */
+ memset(data, 0, tocopy);
+ else {
+ bh = sb_bread(sb, tmp_bh.b_blocknr);
+ if (!bh)
+ return -EIO;
+ memcpy(data, bh->b_data+offset, tocopy);
+ brelse(bh);
+ }
+ offset = 0;
+ toread -= tocopy;
+ data += tocopy;
+ blk++;
+ }
+ return len;
+}
+
+/* Write to quotafile */
+static ssize_t ext2_quota_write(struct super_block *sb, int type,
+ const char *data, size_t len, loff_t off)
+{
+ struct inode *inode = sb_dqopt(sb)->files[type];
+ sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb);
+ int err = 0;
+ int offset = off & (sb->s_blocksize - 1);
+ int tocopy;
+ size_t towrite = len;
+ struct buffer_head tmp_bh;
+ struct buffer_head *bh;
+
+ while (towrite > 0) {
+ tocopy = sb->s_blocksize - offset < towrite ?
+ sb->s_blocksize - offset : towrite;
+
+ tmp_bh.b_state = 0;
+ tmp_bh.b_size = sb->s_blocksize;
+ err = ext2_get_block(inode, blk, &tmp_bh, 1);
+ if (err < 0)
+ goto out;
+ if (offset || tocopy != EXT2_BLOCK_SIZE(sb))
+ bh = sb_bread(sb, tmp_bh.b_blocknr);
+ else
+ bh = sb_getblk(sb, tmp_bh.b_blocknr);
+ if (unlikely(!bh)) {
+ err = -EIO;
+ goto out;
+ }
+ lock_buffer(bh);
+ memcpy(bh->b_data+offset, data, tocopy);
+ flush_dcache_page(bh->b_page);
+ set_buffer_uptodate(bh);
+ mark_buffer_dirty(bh);
+ unlock_buffer(bh);
+ brelse(bh);
+ offset = 0;
+ towrite -= tocopy;
+ data += tocopy;
+ blk++;
+ }
+out:
+ if (len == towrite)
+ return err;
+ if (inode->i_size < off+len-towrite)
+ i_size_write(inode, off+len-towrite);
+ inode->i_version++;
+ inode->i_mtime = inode->i_ctime = CURRENT_TIME;
+ mark_inode_dirty(inode);
+ return len - towrite;
+}
+
+#endif
+
+static struct file_system_type ext2_fs_type = {
+ .owner = THIS_MODULE,
+ .name = "ext2",
+ .mount = ext2_mount,
+ .kill_sb = kill_block_super,
+ .fs_flags = FS_REQUIRES_DEV,
+};
+MODULE_ALIAS_FS("ext2");
+
+static int __init init_ext2_fs(void)
+{
+ int err = init_ext2_xattr();
+ if (err)
+ return err;
+ err = init_inodecache();
+ if (err)
+ goto out1;
+ err = register_filesystem(&ext2_fs_type);
+ if (err)
+ goto out;
+ return 0;
+out:
+ destroy_inodecache();
+out1:
+ exit_ext2_xattr();
+ return err;
+}
+
+static void __exit exit_ext2_fs(void)
+{
+ unregister_filesystem(&ext2_fs_type);
+ destroy_inodecache();
+ exit_ext2_xattr();
+}
+
+MODULE_AUTHOR("Remy Card and others");
+MODULE_DESCRIPTION("Second Extended Filesystem");
+MODULE_LICENSE("GPL");
+module_init(init_ext2_fs)
+module_exit(exit_ext2_fs)
Code Review / kvmfornfv.git / blobdiff