static void ext2_commit_super (struct super_block * sb,
struct ext2_super_block * es)
{
ext2_clear_super_error(sb);
es->s_wtime = cpu_to_le32(get_seconds());
mark_buffer_dirty(EXT2_SB(sb)->s_sbh);
sb->s_dirt = 0;
}
static void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es)
{
ext2_clear_super_error(sb);
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());
mark_buffer_dirty(EXT2_SB(sb)->s_sbh);
sync_dirty_buffer(EXT2_SB(sb)->s_sbh);
sb->s_dirt = 0;
}
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);
}
static int ext2_sync_fs(struct super_block *sb, int wait)
{
struct ext2_super_block *es = EXT2_SB(sb)->s_es;
lock_kernel();
ext2_clear_super_error(sb);
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);
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_mtime = cpu_to_le32(get_seconds());
ext2_sync_super(sb, es);
} else {
ext2_commit_super(sb, es);
}
sb->s_dirt = 0;
unlock_kernel();
return 0;
}
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);
sb->s_iflags |= SB_I_CGROUPWB;
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) {
struct blk_dax_ctl dax = {
.sector = 0,
.size = PAGE_SIZE,
};
if (blocksize != PAGE_SIZE) {
ext2_msg(sb, KERN_ERR,
"error: unsupported blocksize for dax");
goto failed_mount;
}
err = bdev_direct_access(sb->s_bdev, &dax);
if (err < 0) {
switch (err) {
case -EOPNOTSUPP:
ext2_msg(sb, KERN_ERR,
"error: device does not support dax");
break;
case -EINVAL:
ext2_msg(sb, KERN_ERR,
"error: unaligned partition for dax");
break;
default:
ext2_msg(sb, KERN_ERR,
"error: dax access failed (%d)", err);
break;
}
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;
}
#ifdef CONFIG_EXT2_FS_XATTR
sbi->s_mb_cache = ext2_xattr_create_cache();
if (!sbi->s_mb_cache) {
ext2_msg(sb, KERN_ERR, "Failed to create an mb_cache");
goto failed_mount3;
}
#endif
/*
* 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:
if (sbi->s_mb_cache)
ext2_xattr_destroy_cache(sbi->s_mb_cache);
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);
}