linux/fs/hfsplus/super.c
Christoph Hellwig 84adede312 hfsplus: use atomic bitops for the superblock flags
The flags in the HFS+-specific superlock do get modified during runtime,
use atomic bitops to make the modifications SMP safe.

Signed-off-by: Christoph Hellwig <hch@tuxera.com>
2010-10-01 05:45:20 +02:00

544 lines
14 KiB
C

/*
* linux/fs/hfsplus/super.c
*
* Copyright (C) 2001
* Brad Boyer (flar@allandria.com)
* (C) 2003 Ardis Technologies <roman@ardistech.com>
*
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/pagemap.h>
#include <linux/fs.h>
#include <linux/slab.h>
#include <linux/vfs.h>
#include <linux/nls.h>
static struct inode *hfsplus_alloc_inode(struct super_block *sb);
static void hfsplus_destroy_inode(struct inode *inode);
#include "hfsplus_fs.h"
static int hfsplus_system_read_inode(struct inode *inode)
{
struct hfsplus_vh *vhdr = HFSPLUS_SB(inode->i_sb)->s_vhdr;
switch (inode->i_ino) {
case HFSPLUS_EXT_CNID:
hfsplus_inode_read_fork(inode, &vhdr->ext_file);
inode->i_mapping->a_ops = &hfsplus_btree_aops;
break;
case HFSPLUS_CAT_CNID:
hfsplus_inode_read_fork(inode, &vhdr->cat_file);
inode->i_mapping->a_ops = &hfsplus_btree_aops;
break;
case HFSPLUS_ALLOC_CNID:
hfsplus_inode_read_fork(inode, &vhdr->alloc_file);
inode->i_mapping->a_ops = &hfsplus_aops;
break;
case HFSPLUS_START_CNID:
hfsplus_inode_read_fork(inode, &vhdr->start_file);
break;
case HFSPLUS_ATTR_CNID:
hfsplus_inode_read_fork(inode, &vhdr->attr_file);
inode->i_mapping->a_ops = &hfsplus_btree_aops;
break;
default:
return -EIO;
}
return 0;
}
struct inode *hfsplus_iget(struct super_block *sb, unsigned long ino)
{
struct hfs_find_data fd;
struct inode *inode;
int err;
inode = iget_locked(sb, ino);
if (!inode)
return ERR_PTR(-ENOMEM);
if (!(inode->i_state & I_NEW))
return inode;
INIT_LIST_HEAD(&HFSPLUS_I(inode)->open_dir_list);
mutex_init(&HFSPLUS_I(inode)->extents_lock);
HFSPLUS_I(inode)->flags = 0;
HFSPLUS_I(inode)->rsrc_inode = NULL;
atomic_set(&HFSPLUS_I(inode)->opencnt, 0);
if (inode->i_ino >= HFSPLUS_FIRSTUSER_CNID ||
inode->i_ino == HFSPLUS_ROOT_CNID) {
hfs_find_init(HFSPLUS_SB(inode->i_sb)->cat_tree, &fd);
err = hfsplus_find_cat(inode->i_sb, inode->i_ino, &fd);
if (!err)
err = hfsplus_cat_read_inode(inode, &fd);
hfs_find_exit(&fd);
} else {
err = hfsplus_system_read_inode(inode);
}
if (err) {
iget_failed(inode);
return ERR_PTR(err);
}
unlock_new_inode(inode);
return inode;
}
static int hfsplus_system_write_inode(struct inode *inode)
{
struct hfsplus_sb_info *sbi = HFSPLUS_SB(inode->i_sb);
struct hfsplus_vh *vhdr = sbi->s_vhdr;
struct hfsplus_fork_raw *fork;
struct hfs_btree *tree = NULL;
switch (inode->i_ino) {
case HFSPLUS_EXT_CNID:
fork = &vhdr->ext_file;
tree = sbi->ext_tree;
break;
case HFSPLUS_CAT_CNID:
fork = &vhdr->cat_file;
tree = sbi->cat_tree;
break;
case HFSPLUS_ALLOC_CNID:
fork = &vhdr->alloc_file;
break;
case HFSPLUS_START_CNID:
fork = &vhdr->start_file;
break;
case HFSPLUS_ATTR_CNID:
fork = &vhdr->attr_file;
tree = sbi->attr_tree;
default:
return -EIO;
}
if (fork->total_size != cpu_to_be64(inode->i_size)) {
set_bit(HFSPLUS_SB_WRITEBACKUP, &sbi->flags);
inode->i_sb->s_dirt = 1;
}
hfsplus_inode_write_fork(inode, fork);
if (tree)
hfs_btree_write(tree);
return 0;
}
static int hfsplus_write_inode(struct inode *inode,
struct writeback_control *wbc)
{
dprint(DBG_INODE, "hfsplus_write_inode: %lu\n", inode->i_ino);
hfsplus_ext_write_extent(inode);
if (inode->i_ino >= HFSPLUS_FIRSTUSER_CNID ||
inode->i_ino == HFSPLUS_ROOT_CNID)
return hfsplus_cat_write_inode(inode);
else
return hfsplus_system_write_inode(inode);
}
static void hfsplus_evict_inode(struct inode *inode)
{
dprint(DBG_INODE, "hfsplus_evict_inode: %lu\n", inode->i_ino);
truncate_inode_pages(&inode->i_data, 0);
end_writeback(inode);
if (HFSPLUS_IS_RSRC(inode)) {
HFSPLUS_I(HFSPLUS_I(inode)->rsrc_inode)->rsrc_inode = NULL;
iput(HFSPLUS_I(inode)->rsrc_inode);
}
}
int hfsplus_sync_fs(struct super_block *sb, int wait)
{
struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb);
struct hfsplus_vh *vhdr = sbi->s_vhdr;
dprint(DBG_SUPER, "hfsplus_write_super\n");
mutex_lock(&sbi->vh_mutex);
mutex_lock(&sbi->alloc_mutex);
sb->s_dirt = 0;
vhdr->free_blocks = cpu_to_be32(sbi->free_blocks);
vhdr->next_cnid = cpu_to_be32(sbi->next_cnid);
vhdr->folder_count = cpu_to_be32(sbi->folder_count);
vhdr->file_count = cpu_to_be32(sbi->file_count);
mark_buffer_dirty(sbi->s_vhbh);
if (test_and_clear_bit(HFSPLUS_SB_WRITEBACKUP, &sbi->flags)) {
if (sbi->sect_count) {
struct buffer_head *bh;
u32 block, offset;
block = sbi->blockoffset;
block += (sbi->sect_count - 2) >> (sb->s_blocksize_bits - 9);
offset = ((sbi->sect_count - 2) << 9) & (sb->s_blocksize - 1);
printk(KERN_DEBUG "hfs: backup: %u,%u,%u,%u\n",
sbi->blockoffset, sbi->sect_count,
block, offset);
bh = sb_bread(sb, block);
if (bh) {
vhdr = (struct hfsplus_vh *)(bh->b_data + offset);
if (be16_to_cpu(vhdr->signature) == HFSPLUS_VOLHEAD_SIG) {
memcpy(vhdr, sbi->s_vhdr, sizeof(*vhdr));
mark_buffer_dirty(bh);
brelse(bh);
} else
printk(KERN_WARNING "hfs: backup not found!\n");
}
}
}
mutex_unlock(&sbi->alloc_mutex);
mutex_unlock(&sbi->vh_mutex);
return 0;
}
static void hfsplus_write_super(struct super_block *sb)
{
if (!(sb->s_flags & MS_RDONLY))
hfsplus_sync_fs(sb, 1);
else
sb->s_dirt = 0;
}
static void hfsplus_put_super(struct super_block *sb)
{
struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb);
dprint(DBG_SUPER, "hfsplus_put_super\n");
if (!sb->s_fs_info)
return;
if (sb->s_dirt)
hfsplus_write_super(sb);
if (!(sb->s_flags & MS_RDONLY) && sbi->s_vhdr) {
struct hfsplus_vh *vhdr = sbi->s_vhdr;
vhdr->modify_date = hfsp_now2mt();
vhdr->attributes |= cpu_to_be32(HFSPLUS_VOL_UNMNT);
vhdr->attributes &= cpu_to_be32(~HFSPLUS_VOL_INCNSTNT);
mark_buffer_dirty(sbi->s_vhbh);
sync_dirty_buffer(sbi->s_vhbh);
}
hfs_btree_close(sbi->cat_tree);
hfs_btree_close(sbi->ext_tree);
iput(sbi->alloc_file);
iput(sbi->hidden_dir);
brelse(sbi->s_vhbh);
unload_nls(sbi->nls);
kfree(sb->s_fs_info);
sb->s_fs_info = NULL;
}
static int hfsplus_statfs(struct dentry *dentry, struct kstatfs *buf)
{
struct super_block *sb = dentry->d_sb;
struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb);
u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
buf->f_type = HFSPLUS_SUPER_MAGIC;
buf->f_bsize = sb->s_blocksize;
buf->f_blocks = sbi->total_blocks << sbi->fs_shift;
buf->f_bfree = sbi->free_blocks << sbi->fs_shift;
buf->f_bavail = buf->f_bfree;
buf->f_files = 0xFFFFFFFF;
buf->f_ffree = 0xFFFFFFFF - sbi->next_cnid;
buf->f_fsid.val[0] = (u32)id;
buf->f_fsid.val[1] = (u32)(id >> 32);
buf->f_namelen = HFSPLUS_MAX_STRLEN;
return 0;
}
static int hfsplus_remount(struct super_block *sb, int *flags, char *data)
{
if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
return 0;
if (!(*flags & MS_RDONLY)) {
struct hfsplus_vh *vhdr = HFSPLUS_SB(sb)->s_vhdr;
struct hfsplus_sb_info sbi;
memset(&sbi, 0, sizeof(struct hfsplus_sb_info));
sbi.nls = HFSPLUS_SB(sb)->nls;
if (!hfsplus_parse_options(data, &sbi))
return -EINVAL;
if (!(vhdr->attributes & cpu_to_be32(HFSPLUS_VOL_UNMNT))) {
printk(KERN_WARNING "hfs: filesystem was not cleanly unmounted, "
"running fsck.hfsplus is recommended. leaving read-only.\n");
sb->s_flags |= MS_RDONLY;
*flags |= MS_RDONLY;
} else if (test_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, leaving read-only.\n");
sb->s_flags |= MS_RDONLY;
*flags |= MS_RDONLY;
} else if (vhdr->attributes & cpu_to_be32(HFSPLUS_VOL_JOURNALED)) {
printk(KERN_WARNING "hfs: filesystem is marked journaled, leaving read-only.\n");
sb->s_flags |= MS_RDONLY;
*flags |= MS_RDONLY;
}
}
return 0;
}
static const struct super_operations hfsplus_sops = {
.alloc_inode = hfsplus_alloc_inode,
.destroy_inode = hfsplus_destroy_inode,
.write_inode = hfsplus_write_inode,
.evict_inode = hfsplus_evict_inode,
.put_super = hfsplus_put_super,
.write_super = hfsplus_write_super,
.sync_fs = hfsplus_sync_fs,
.statfs = hfsplus_statfs,
.remount_fs = hfsplus_remount,
.show_options = hfsplus_show_options,
};
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 = -EINVAL;
sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
if (!sbi)
return -ENOMEM;
sb->s_fs_info = sbi;
mutex_init(&sbi->alloc_mutex);
mutex_init(&sbi->vh_mutex);
hfsplus_fill_defaults(sbi);
if (!hfsplus_parse_options(data, sbi)) {
printk(KERN_ERR "hfs: unable to parse mount options\n");
err = -EINVAL;
goto cleanup;
}
/* 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");
err = -EINVAL;
goto cleanup;
}
/* Grab the volume header */
if (hfsplus_read_wrapper(sb)) {
if (!silent)
printk(KERN_WARNING "hfs: unable to find HFS+ superblock\n");
err = -EINVAL;
goto cleanup;
}
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 cleanup;
}
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 cleanup;
}
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 cleanup;
}
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 cleanup;
}
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 cleanup;
}
sb->s_root = d_alloc_root(root);
if (!sb->s_root) {
iput(root);
err = -ENOMEM;
goto cleanup;
}
sb->s_root->d_op = &hfsplus_dentry_operations;
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 cleanup;
inode = hfsplus_iget(sb, be32_to_cpu(entry.folder.id));
if (IS_ERR(inode)) {
err = PTR_ERR(inode);
goto cleanup;
}
sbi->hidden_dir = inode;
} else
hfs_find_exit(&fd);
if (sb->s_flags & MS_RDONLY)
goto out;
/* 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);
mark_buffer_dirty(sbi->s_vhbh);
sync_dirty_buffer(sbi->s_vhbh);
if (!sbi->hidden_dir) {
printk(KERN_DEBUG "hfs: create hidden dir...\n");
mutex_lock(&sbi->vh_mutex);
sbi->hidden_dir = hfsplus_new_inode(sb, S_IFDIR);
hfsplus_create_cat(sbi->hidden_dir->i_ino, sb->s_root->d_inode,
&str, sbi->hidden_dir);
mutex_unlock(&sbi->vh_mutex);
mark_inode_dirty(sbi->hidden_dir);
}
out:
unload_nls(sbi->nls);
sbi->nls = nls;
return 0;
cleanup:
hfsplus_put_super(sb);
unload_nls(nls);
return err;
}
MODULE_AUTHOR("Brad Boyer");
MODULE_DESCRIPTION("Extended Macintosh Filesystem");
MODULE_LICENSE("GPL");
static struct kmem_cache *hfsplus_inode_cachep;
static struct inode *hfsplus_alloc_inode(struct super_block *sb)
{
struct hfsplus_inode_info *i;
i = kmem_cache_alloc(hfsplus_inode_cachep, GFP_KERNEL);
return i ? &i->vfs_inode : NULL;
}
static void hfsplus_destroy_inode(struct inode *inode)
{
kmem_cache_free(hfsplus_inode_cachep, HFSPLUS_I(inode));
}
#define HFSPLUS_INODE_SIZE sizeof(struct hfsplus_inode_info)
static int hfsplus_get_sb(struct file_system_type *fs_type,
int flags, const char *dev_name, void *data,
struct vfsmount *mnt)
{
return get_sb_bdev(fs_type, flags, dev_name, data, hfsplus_fill_super,
mnt);
}
static struct file_system_type hfsplus_fs_type = {
.owner = THIS_MODULE,
.name = "hfsplus",
.get_sb = hfsplus_get_sb,
.kill_sb = kill_block_super,
.fs_flags = FS_REQUIRES_DEV,
};
static void hfsplus_init_once(void *p)
{
struct hfsplus_inode_info *i = p;
inode_init_once(&i->vfs_inode);
}
static int __init init_hfsplus_fs(void)
{
int err;
hfsplus_inode_cachep = kmem_cache_create("hfsplus_icache",
HFSPLUS_INODE_SIZE, 0, SLAB_HWCACHE_ALIGN,
hfsplus_init_once);
if (!hfsplus_inode_cachep)
return -ENOMEM;
err = register_filesystem(&hfsplus_fs_type);
if (err)
kmem_cache_destroy(hfsplus_inode_cachep);
return err;
}
static void __exit exit_hfsplus_fs(void)
{
unregister_filesystem(&hfsplus_fs_type);
kmem_cache_destroy(hfsplus_inode_cachep);
}
module_init(init_hfsplus_fs)
module_exit(exit_hfsplus_fs)