/*
* hfs_mdb_get()
*
* Build the in-core MDB for a filesystem, including
* the B-trees and the volume bitmap.
*/
int hfs_mdb_get(struct super_block *sb)
{
struct buffer_head *bh;
struct hfs_mdb *mdb, *mdb2;
unsigned int block;
char *ptr;
int off2, len, size, sect;
sector_t part_start, part_size;
loff_t off;
__be16 attrib;
/* set the device driver to 512-byte blocks */
size = sb_min_blocksize(sb, HFS_SECTOR_SIZE);
if (!size)
return -EINVAL;
if (hfs_get_last_session(sb, &part_start, &part_size))
return -EINVAL;
while (1) {
/* See if this is an HFS filesystem */
bh = sb_bread512(sb, part_start + HFS_MDB_BLK, mdb);
if (!bh)
goto out;
if (mdb->drSigWord == cpu_to_be16(HFS_SUPER_MAGIC))
break;
brelse(bh);
/* check for a partition block
* (should do this only for cdrom/loop though)
*/
if (hfs_part_find(sb, &part_start, &part_size))
goto out;
}
HFS_SB(sb)->alloc_blksz = size = be32_to_cpu(mdb->drAlBlkSiz);
if (!size || (size & (HFS_SECTOR_SIZE - 1))) {
hfs_warn("hfs_fs: bad allocation block size %d\n", size);
goto out_bh;
}
size = min(HFS_SB(sb)->alloc_blksz, (u32)PAGE_SIZE);
/* size must be a multiple of 512 */
while (size & (size - 1))
size -= HFS_SECTOR_SIZE;
sect = be16_to_cpu(mdb->drAlBlSt) + part_start;
/* align block size to first sector */
while (sect & ((size - 1) >> HFS_SECTOR_SIZE_BITS))
size >>= 1;
/* align block size to weird alloc size */
while (HFS_SB(sb)->alloc_blksz & (size - 1))
size >>= 1;
brelse(bh);
if (!sb_set_blocksize(sb, size)) {
printk("hfs_fs: unable to set blocksize to %u\n", size);
goto out;
}
bh = sb_bread512(sb, part_start + HFS_MDB_BLK, mdb);
if (!bh)
goto out;
if (mdb->drSigWord != cpu_to_be16(HFS_SUPER_MAGIC))
goto out_bh;
HFS_SB(sb)->mdb_bh = bh;
HFS_SB(sb)->mdb = mdb;
/* These parameters are read from the MDB, and never written */
HFS_SB(sb)->part_start = part_start;
HFS_SB(sb)->fs_ablocks = be16_to_cpu(mdb->drNmAlBlks);
HFS_SB(sb)->fs_div = HFS_SB(sb)->alloc_blksz >> sb->s_blocksize_bits;
HFS_SB(sb)->clumpablks = be32_to_cpu(mdb->drClpSiz) /
HFS_SB(sb)->alloc_blksz;
if (!HFS_SB(sb)->clumpablks)
HFS_SB(sb)->clumpablks = 1;
HFS_SB(sb)->fs_start = (be16_to_cpu(mdb->drAlBlSt) + part_start) >>
(sb->s_blocksize_bits - HFS_SECTOR_SIZE_BITS);
/* These parameters are read from and written to the MDB */
HFS_SB(sb)->free_ablocks = be16_to_cpu(mdb->drFreeBks);
HFS_SB(sb)->next_id = be32_to_cpu(mdb->drNxtCNID);
HFS_SB(sb)->root_files = be16_to_cpu(mdb->drNmFls);
HFS_SB(sb)->root_dirs = be16_to_cpu(mdb->drNmRtDirs);
HFS_SB(sb)->file_count = be32_to_cpu(mdb->drFilCnt);
HFS_SB(sb)->folder_count = be32_to_cpu(mdb->drDirCnt);
/* TRY to get the alternate (backup) MDB. */
sect = part_start + part_size - 2;
bh = sb_bread512(sb, sect, mdb2);
if (bh) {
if (mdb2->drSigWord == cpu_to_be16(HFS_SUPER_MAGIC)) {
HFS_SB(sb)->alt_mdb_bh = bh;
HFS_SB(sb)->alt_mdb = mdb2;
} else
brelse(bh);
}
if (!HFS_SB(sb)->alt_mdb) {
hfs_warn("hfs_fs: unable to locate alternate MDB\n");
hfs_warn("hfs_fs: continuing without an alternate MDB\n");
}
HFS_SB(sb)->bitmap = (__be32 *)__get_free_pages(GFP_KERNEL, PAGE_SIZE < 8192 ? 1 : 0);
if (!HFS_SB(sb)->bitmap)
goto out;
/* read in the bitmap */
block = be16_to_cpu(mdb->drVBMSt) + part_start;
off = (loff_t)block << HFS_SECTOR_SIZE_BITS;
size = (HFS_SB(sb)->fs_ablocks + 8) / 8;
ptr = (u8 *)HFS_SB(sb)->bitmap;
while (size) {
bh = sb_bread(sb, off >> sb->s_blocksize_bits);
if (!bh) {
hfs_warn("hfs_fs: unable to read volume bitmap\n");
goto out;
}
off2 = off & (sb->s_blocksize - 1);
len = min((int)sb->s_blocksize - off2, size);
memcpy(ptr, bh->b_data + off2, len);
brelse(bh);
ptr += len;
off += len;
size -= len;
}
HFS_SB(sb)->ext_tree = hfs_btree_open(sb, HFS_EXT_CNID, hfs_ext_keycmp);
if (!HFS_SB(sb)->ext_tree) {
hfs_warn("hfs_fs: unable to open extent tree\n");
goto out;
}
HFS_SB(sb)->cat_tree = hfs_btree_open(sb, HFS_CAT_CNID, hfs_cat_keycmp);
if (!HFS_SB(sb)->cat_tree) {
hfs_warn("hfs_fs: unable to open catalog tree\n");
goto out;
}
attrib = mdb->drAtrb;
if (!(attrib & cpu_to_be16(HFS_SB_ATTRIB_UNMNT))
|| (attrib & cpu_to_be16(HFS_SB_ATTRIB_INCNSTNT))) {
hfs_warn("HFS-fs warning: Filesystem was not cleanly unmounted, "
"running fsck.hfs is recommended. mounting read-only.\n");
sb->s_flags |= MS_RDONLY;
}
if ((attrib & cpu_to_be16(HFS_SB_ATTRIB_SLOCK))) {
hfs_warn("HFS-fs: Filesystem is marked locked, mounting read-only.\n");
sb->s_flags |= MS_RDONLY;
}
if (!(sb->s_flags & MS_RDONLY)) {
/* Mark the volume uncleanly unmounted in case we crash */
mdb->drAtrb = attrib & cpu_to_be16(~HFS_SB_ATTRIB_UNMNT);
mdb->drAtrb = attrib | cpu_to_be16(HFS_SB_ATTRIB_INCNSTNT);
mdb->drWrCnt = cpu_to_be32(be32_to_cpu(mdb->drWrCnt) + 1);
mdb->drLsMod = hfs_mtime();
mark_buffer_dirty(HFS_SB(sb)->mdb_bh);
hfs_buffer_sync(HFS_SB(sb)->mdb_bh);
}
return 0;
out_bh:
brelse(bh);
out:
hfs_mdb_put(sb);
return -EIO;
}
static int hfsplus_fill_super(struct super_block *sb, void *data, int silent)
{
struct hfsplus_vh *vhdr;
struct hfsplus_sb_info *sbi;
hfsplus_cat_entry entry;
struct hfs_find_data fd;
struct inode *root, *inode;
struct qstr str;
struct nls_table *nls = NULL;
int err;
err = -EINVAL;
sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
if (!sbi)
goto out;
sb->s_fs_info = sbi;
mutex_init(&sbi->alloc_mutex);
mutex_init(&sbi->vh_mutex);
hfsplus_fill_defaults(sbi);
err = -EINVAL;
if (!hfsplus_parse_options(data, sbi)) {
printk(KERN_ERR "hfs: unable to parse mount options\n");
goto out_unload_nls;
}
/* temporarily use utf8 to correctly find the hidden dir below */
nls = sbi->nls;
sbi->nls = load_nls("utf8");
if (!sbi->nls) {
printk(KERN_ERR "hfs: unable to load nls for utf8\n");
goto out_unload_nls;
}
/* Grab the volume header */
if (hfsplus_read_wrapper(sb)) {
if (!silent)
printk(KERN_WARNING "hfs: unable to find HFS+ superblock\n");
goto out_unload_nls;
}
vhdr = sbi->s_vhdr;
/* Copy parts of the volume header into the superblock */
sb->s_magic = HFSPLUS_VOLHEAD_SIG;
if (be16_to_cpu(vhdr->version) < HFSPLUS_MIN_VERSION ||
be16_to_cpu(vhdr->version) > HFSPLUS_CURRENT_VERSION) {
printk(KERN_ERR "hfs: wrong filesystem version\n");
goto out_free_vhdr;
}
sbi->total_blocks = be32_to_cpu(vhdr->total_blocks);
sbi->free_blocks = be32_to_cpu(vhdr->free_blocks);
sbi->next_cnid = be32_to_cpu(vhdr->next_cnid);
sbi->file_count = be32_to_cpu(vhdr->file_count);
sbi->folder_count = be32_to_cpu(vhdr->folder_count);
sbi->data_clump_blocks =
be32_to_cpu(vhdr->data_clump_sz) >> sbi->alloc_blksz_shift;
if (!sbi->data_clump_blocks)
sbi->data_clump_blocks = 1;
sbi->rsrc_clump_blocks =
be32_to_cpu(vhdr->rsrc_clump_sz) >> sbi->alloc_blksz_shift;
if (!sbi->rsrc_clump_blocks)
sbi->rsrc_clump_blocks = 1;
/* Set up operations so we can load metadata */
sb->s_op = &hfsplus_sops;
sb->s_maxbytes = MAX_LFS_FILESIZE;
if (!(vhdr->attributes & cpu_to_be32(HFSPLUS_VOL_UNMNT))) {
printk(KERN_WARNING "hfs: Filesystem was "
"not cleanly unmounted, "
"running fsck.hfsplus is recommended. "
"mounting read-only.\n");
sb->s_flags |= MS_RDONLY;
} else if (test_and_clear_bit(HFSPLUS_SB_FORCE, &sbi->flags)) {
/* nothing */
} else if (vhdr->attributes & cpu_to_be32(HFSPLUS_VOL_SOFTLOCK)) {
printk(KERN_WARNING "hfs: Filesystem is marked locked, mounting read-only.\n");
sb->s_flags |= MS_RDONLY;
} else if ((vhdr->attributes & cpu_to_be32(HFSPLUS_VOL_JOURNALED)) &&
!(sb->s_flags & MS_RDONLY)) {
printk(KERN_WARNING "hfs: write access to "
"a journaled filesystem is not supported, "
"use the force option at your own risk, "
"mounting read-only.\n");
sb->s_flags |= MS_RDONLY;
}
/* Load metadata objects (B*Trees) */
sbi->ext_tree = hfs_btree_open(sb, HFSPLUS_EXT_CNID);
if (!sbi->ext_tree) {
printk(KERN_ERR "hfs: failed to load extents file\n");
goto out_free_vhdr;
}
sbi->cat_tree = hfs_btree_open(sb, HFSPLUS_CAT_CNID);
if (!sbi->cat_tree) {
printk(KERN_ERR "hfs: failed to load catalog file\n");
goto out_close_ext_tree;
}
inode = hfsplus_iget(sb, HFSPLUS_ALLOC_CNID);
if (IS_ERR(inode)) {
printk(KERN_ERR "hfs: failed to load allocation file\n");
err = PTR_ERR(inode);
goto out_close_cat_tree;
}
sbi->alloc_file = inode;
/* Load the root directory */
root = hfsplus_iget(sb, HFSPLUS_ROOT_CNID);
if (IS_ERR(root)) {
printk(KERN_ERR "hfs: failed to load root directory\n");
err = PTR_ERR(root);
goto out_put_alloc_file;
}
str.len = sizeof(HFSP_HIDDENDIR_NAME) - 1;
str.name = HFSP_HIDDENDIR_NAME;
hfs_find_init(sbi->cat_tree, &fd);
hfsplus_cat_build_key(sb, fd.search_key, HFSPLUS_ROOT_CNID, &str);
if (!hfs_brec_read(&fd, &entry, sizeof(entry))) {
hfs_find_exit(&fd);
if (entry.type != cpu_to_be16(HFSPLUS_FOLDER))
goto out_put_root;
inode = hfsplus_iget(sb, be32_to_cpu(entry.folder.id));
if (IS_ERR(inode)) {
err = PTR_ERR(inode);
goto out_put_root;
}
sbi->hidden_dir = inode;
} else
hfs_find_exit(&fd);
if (!(sb->s_flags & MS_RDONLY)) {
/*
* H+LX == hfsplusutils, H+Lx == this driver, H+lx is unused
* all three are registered with Apple for our use
*/
vhdr->last_mount_vers = cpu_to_be32(HFSP_MOUNT_VERSION);
vhdr->modify_date = hfsp_now2mt();
be32_add_cpu(&vhdr->write_count, 1);
vhdr->attributes &= cpu_to_be32(~HFSPLUS_VOL_UNMNT);
vhdr->attributes |= cpu_to_be32(HFSPLUS_VOL_INCNSTNT);
hfsplus_sync_fs(sb, 1);
if (!sbi->hidden_dir) {
mutex_lock(&sbi->vh_mutex);
sbi->hidden_dir = hfsplus_new_inode(sb, S_IFDIR);
hfsplus_create_cat(sbi->hidden_dir->i_ino, root, &str,
sbi->hidden_dir);
mutex_unlock(&sbi->vh_mutex);
hfsplus_mark_inode_dirty(sbi->hidden_dir,
HFSPLUS_I_CAT_DIRTY);
}
}
sb->s_d_op = &hfsplus_dentry_operations;
sb->s_root = d_alloc_root(root);
if (!sb->s_root) {
err = -ENOMEM;
goto out_put_hidden_dir;
}
unload_nls(sbi->nls);
sbi->nls = nls;
return 0;
out_put_hidden_dir:
iput(sbi->hidden_dir);
out_put_root:
iput(root);
out_put_alloc_file:
iput(sbi->alloc_file);
out_close_cat_tree:
hfs_btree_close(sbi->cat_tree);
out_close_ext_tree:
hfs_btree_close(sbi->ext_tree);
out_free_vhdr:
kfree(sbi->s_vhdr);
kfree(sbi->s_backup_vhdr);
out_unload_nls:
unload_nls(sbi->nls);
unload_nls(nls);
kfree(sbi);
out:
return err;
}
