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linux-zen-desktop/fs/hfsplus/super.c

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// SPDX-License-Identifier: GPL-2.0-only
/*
* 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/blkdev.h>
#include <linux/backing-dev.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_free_inode(struct inode *inode);
#include "hfsplus_fs.h"
#include "xattr.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);
spin_lock_init(&HFSPLUS_I(inode)->open_dir_lock);
mutex_init(&HFSPLUS_I(inode)->extents_lock);
HFSPLUS_I(inode)->flags = 0;
HFSPLUS_I(inode)->extent_state = 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) {
err = hfs_find_init(HFSPLUS_SB(inode->i_sb)->cat_tree, &fd);
if (!err) {
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;
break;
default:
return -EIO;
}
if (fork->total_size != cpu_to_be64(inode->i_size)) {
set_bit(HFSPLUS_SB_WRITEBACKUP, &sbi->flags);
hfsplus_mark_mdb_dirty(inode->i_sb);
}
hfsplus_inode_write_fork(inode, fork);
if (tree) {
int err = hfs_btree_write(tree);
if (err) {
pr_err("b-tree write err: %d, ino %lu\n",
err, inode->i_ino);
return err;
}
}
return 0;
}
static int hfsplus_write_inode(struct inode *inode,
struct writeback_control *wbc)
{
int err;
hfs_dbg(INODE, "hfsplus_write_inode: %lu\n", inode->i_ino);
err = hfsplus_ext_write_extent(inode);
if (err)
return err;
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)
{
hfs_dbg(INODE, "hfsplus_evict_inode: %lu\n", inode->i_ino);
truncate_inode_pages_final(&inode->i_data);
clear_inode(inode);
if (HFSPLUS_IS_RSRC(inode)) {
HFSPLUS_I(HFSPLUS_I(inode)->rsrc_inode)->rsrc_inode = NULL;
iput(HFSPLUS_I(inode)->rsrc_inode);
}
}
static 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;
int write_backup = 0;
int error, error2;
if (!wait)
return 0;
hfs_dbg(SUPER, "hfsplus_sync_fs\n");
/*
* Explicitly write out the special metadata inodes.
*
* While these special inodes are marked as hashed and written
* out peridocically by the flusher threads we redirty them
* during writeout of normal inodes, and thus the life lock
* prevents us from getting the latest state to disk.
*/
error = filemap_write_and_wait(sbi->cat_tree->inode->i_mapping);
error2 = filemap_write_and_wait(sbi->ext_tree->inode->i_mapping);
if (!error)
error = error2;
if (sbi->attr_tree) {
error2 =
filemap_write_and_wait(sbi->attr_tree->inode->i_mapping);
if (!error)
error = error2;
}
error2 = filemap_write_and_wait(sbi->alloc_file->i_mapping);
if (!error)
error = error2;
mutex_lock(&sbi->vh_mutex);
mutex_lock(&sbi->alloc_mutex);
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);
if (test_and_clear_bit(HFSPLUS_SB_WRITEBACKUP, &sbi->flags)) {
memcpy(sbi->s_backup_vhdr, sbi->s_vhdr, sizeof(*sbi->s_vhdr));
write_backup = 1;
}
error2 = hfsplus_submit_bio(sb,
sbi->part_start + HFSPLUS_VOLHEAD_SECTOR,
sbi->s_vhdr_buf, NULL, REQ_OP_WRITE |
REQ_SYNC);
if (!error)
error = error2;
if (!write_backup)
goto out;
error2 = hfsplus_submit_bio(sb,
sbi->part_start + sbi->sect_count - 2,
sbi->s_backup_vhdr_buf, NULL, REQ_OP_WRITE |
REQ_SYNC);
if (!error)
error2 = error;
out:
mutex_unlock(&sbi->alloc_mutex);
mutex_unlock(&sbi->vh_mutex);
if (!test_bit(HFSPLUS_SB_NOBARRIER, &sbi->flags))
blkdev_issue_flush(sb->s_bdev);
return error;
}
static void delayed_sync_fs(struct work_struct *work)
{
int err;
struct hfsplus_sb_info *sbi;
sbi = container_of(work, struct hfsplus_sb_info, sync_work.work);
spin_lock(&sbi->work_lock);
sbi->work_queued = 0;
spin_unlock(&sbi->work_lock);
err = hfsplus_sync_fs(sbi->alloc_file->i_sb, 1);
if (err)
pr_err("delayed sync fs err %d\n", err);
}
void hfsplus_mark_mdb_dirty(struct super_block *sb)
{
struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb);
unsigned long delay;
if (sb_rdonly(sb))
return;
spin_lock(&sbi->work_lock);
if (!sbi->work_queued) {
delay = msecs_to_jiffies(dirty_writeback_interval * 10);
queue_delayed_work(system_long_wq, &sbi->sync_work, delay);
sbi->work_queued = 1;
}
spin_unlock(&sbi->work_lock);
}
static void hfsplus_put_super(struct super_block *sb)
{
struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb);
hfs_dbg(SUPER, "hfsplus_put_super\n");
cancel_delayed_work_sync(&sbi->sync_work);
if (!sb_rdonly(sb) && 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);
hfsplus_sync_fs(sb, 1);
}
iput(sbi->alloc_file);
iput(sbi->hidden_dir);
hfs_btree_close(sbi->attr_tree);
hfs_btree_close(sbi->cat_tree);
hfs_btree_close(sbi->ext_tree);
kfree(sbi->s_vhdr_buf);
kfree(sbi->s_backup_vhdr_buf);
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 = u64_to_fsid(id);
buf->f_namelen = HFSPLUS_MAX_STRLEN;
return 0;
}
static int hfsplus_remount(struct super_block *sb, int *flags, char *data)
{
sync_filesystem(sb);
if ((bool)(*flags & SB_RDONLY) == sb_rdonly(sb))
return 0;
if (!(*flags & SB_RDONLY)) {
struct hfsplus_vh *vhdr = HFSPLUS_SB(sb)->s_vhdr;
int force = 0;
if (!hfsplus_parse_options_remount(data, &force))
return -EINVAL;
if (!(vhdr->attributes & cpu_to_be32(HFSPLUS_VOL_UNMNT))) {
pr_warn("filesystem was not cleanly unmounted, running fsck.hfsplus is recommended. leaving read-only.\n");
sb->s_flags |= SB_RDONLY;
*flags |= SB_RDONLY;
} else if (force) {
/* nothing */
} else if (vhdr->attributes &
cpu_to_be32(HFSPLUS_VOL_SOFTLOCK)) {
pr_warn("filesystem is marked locked, leaving read-only.\n");
sb->s_flags |= SB_RDONLY;
*flags |= SB_RDONLY;
} else if (vhdr->attributes &
cpu_to_be32(HFSPLUS_VOL_JOURNALED)) {
pr_warn("filesystem is marked journaled, leaving read-only.\n");
sb->s_flags |= SB_RDONLY;
*flags |= SB_RDONLY;
}
}
return 0;
}
static const struct super_operations hfsplus_sops = {
.alloc_inode = hfsplus_alloc_inode,
.free_inode = hfsplus_free_inode,
.write_inode = hfsplus_write_inode,
.evict_inode = hfsplus_evict_inode,
.put_super = hfsplus_put_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;
u64 last_fs_block, last_fs_page;
int err;
err = -ENOMEM;
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);
spin_lock_init(&sbi->work_lock);
INIT_DELAYED_WORK(&sbi->sync_work, delayed_sync_fs);
hfsplus_fill_defaults(sbi);
err = -EINVAL;
if (!hfsplus_parse_options(data, sbi)) {
pr_err("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) {
pr_err("unable to load nls for utf8\n");
goto out_unload_nls;
}
/* Grab the volume header */
if (hfsplus_read_wrapper(sb)) {
if (!silent)
pr_warn("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) {
pr_err("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;
err = -EFBIG;
last_fs_block = sbi->total_blocks - 1;
last_fs_page = (last_fs_block << sbi->alloc_blksz_shift) >>
PAGE_SHIFT;
if ((last_fs_block > (sector_t)(~0ULL) >> (sbi->alloc_blksz_shift - 9)) ||
(last_fs_page > (pgoff_t)(~0ULL))) {
pr_err("filesystem size too large\n");
goto out_free_vhdr;
}
/* 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))) {
pr_warn("Filesystem was not cleanly unmounted, running fsck.hfsplus is recommended. mounting read-only.\n");
sb->s_flags |= SB_RDONLY;
} else if (test_and_clear_bit(HFSPLUS_SB_FORCE, &sbi->flags)) {
/* nothing */
} else if (vhdr->attributes & cpu_to_be32(HFSPLUS_VOL_SOFTLOCK)) {
pr_warn("Filesystem is marked locked, mounting read-only.\n");
sb->s_flags |= SB_RDONLY;
} else if ((vhdr->attributes & cpu_to_be32(HFSPLUS_VOL_JOURNALED)) &&
!sb_rdonly(sb)) {
pr_warn("write access to a journaled filesystem is not supported, use the force option at your own risk, mounting read-only.\n");
sb->s_flags |= SB_RDONLY;
}
err = -EINVAL;
/* Load metadata objects (B*Trees) */
sbi->ext_tree = hfs_btree_open(sb, HFSPLUS_EXT_CNID);
if (!sbi->ext_tree) {
pr_err("failed to load extents file\n");
goto out_free_vhdr;
}
sbi->cat_tree = hfs_btree_open(sb, HFSPLUS_CAT_CNID);
if (!sbi->cat_tree) {
pr_err("failed to load catalog file\n");
goto out_close_ext_tree;
}
atomic_set(&sbi->attr_tree_state, HFSPLUS_EMPTY_ATTR_TREE);
if (vhdr->attr_file.total_blocks != 0) {
sbi->attr_tree = hfs_btree_open(sb, HFSPLUS_ATTR_CNID);
if (!sbi->attr_tree) {
pr_err("failed to load attributes file\n");
goto out_close_cat_tree;
}
atomic_set(&sbi->attr_tree_state, HFSPLUS_VALID_ATTR_TREE);
}
sb->s_xattr = hfsplus_xattr_handlers;
inode = hfsplus_iget(sb, HFSPLUS_ALLOC_CNID);
if (IS_ERR(inode)) {
pr_err("failed to load allocation file\n");
err = PTR_ERR(inode);
goto out_close_attr_tree;
}
sbi->alloc_file = inode;
/* Load the root directory */
root = hfsplus_iget(sb, HFSPLUS_ROOT_CNID);
if (IS_ERR(root)) {
pr_err("failed to load root directory\n");
err = PTR_ERR(root);
goto out_put_alloc_file;
}
sb->s_d_op = &hfsplus_dentry_operations;
sb->s_root = d_make_root(root);
if (!sb->s_root) {
err = -ENOMEM;
goto out_put_alloc_file;
}
str.len = sizeof(HFSP_HIDDENDIR_NAME) - 1;
str.name = HFSP_HIDDENDIR_NAME;
err = hfs_find_init(sbi->cat_tree, &fd);
if (err)
goto out_put_root;
err = hfsplus_cat_build_key(sb, fd.search_key, HFSPLUS_ROOT_CNID, &str);
if (unlikely(err < 0))
goto out_put_root;
if (!hfs_brec_read(&fd, &entry, sizeof(entry))) {
hfs_find_exit(&fd);
if (entry.type != cpu_to_be16(HFSPLUS_FOLDER)) {
err = -EINVAL;
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_rdonly(sb)) {
/*
* 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, root, S_IFDIR);
if (!sbi->hidden_dir) {
mutex_unlock(&sbi->vh_mutex);
err = -ENOMEM;
goto out_put_root;
}
err = hfsplus_create_cat(sbi->hidden_dir->i_ino, root,
&str, sbi->hidden_dir);
if (err) {
mutex_unlock(&sbi->vh_mutex);
goto out_put_hidden_dir;
}
err = hfsplus_init_security(sbi->hidden_dir,
root, &str);
if (err == -EOPNOTSUPP)
err = 0; /* Operation is not supported. */
else if (err) {
/*
* Try to delete anyway without
* error analysis.
*/
hfsplus_delete_cat(sbi->hidden_dir->i_ino,
root, &str);
mutex_unlock(&sbi->vh_mutex);
goto out_put_hidden_dir;
}
mutex_unlock(&sbi->vh_mutex);
hfsplus_mark_inode_dirty(sbi->hidden_dir,
HFSPLUS_I_CAT_DIRTY);
}
}
unload_nls(sbi->nls);
sbi->nls = nls;
return 0;
out_put_hidden_dir:
cancel_delayed_work_sync(&sbi->sync_work);
iput(sbi->hidden_dir);
out_put_root:
dput(sb->s_root);
sb->s_root = NULL;
out_put_alloc_file:
iput(sbi->alloc_file);
out_close_attr_tree:
hfs_btree_close(sbi->attr_tree);
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_buf);
kfree(sbi->s_backup_vhdr_buf);
out_unload_nls:
unload_nls(sbi->nls);
unload_nls(nls);
kfree(sbi);
out:
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 = alloc_inode_sb(sb, hfsplus_inode_cachep, GFP_KERNEL);
return i ? &i->vfs_inode : NULL;
}
static void hfsplus_free_inode(struct inode *inode)
{
kmem_cache_free(hfsplus_inode_cachep, HFSPLUS_I(inode));
}
#define HFSPLUS_INODE_SIZE sizeof(struct hfsplus_inode_info)
static struct dentry *hfsplus_mount(struct file_system_type *fs_type,
int flags, const char *dev_name, void *data)
{
return mount_bdev(fs_type, flags, dev_name, data, hfsplus_fill_super);
}
static struct file_system_type hfsplus_fs_type = {
.owner = THIS_MODULE,
.name = "hfsplus",
.mount = hfsplus_mount,
.kill_sb = kill_block_super,
.fs_flags = FS_REQUIRES_DEV,
};
MODULE_ALIAS_FS("hfsplus");
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|SLAB_ACCOUNT,
hfsplus_init_once);
if (!hfsplus_inode_cachep)
return -ENOMEM;
err = hfsplus_create_attr_tree_cache();
if (err)
goto destroy_inode_cache;
err = register_filesystem(&hfsplus_fs_type);
if (err)
goto destroy_attr_tree_cache;
return 0;
destroy_attr_tree_cache:
hfsplus_destroy_attr_tree_cache();
destroy_inode_cache:
kmem_cache_destroy(hfsplus_inode_cachep);
return err;
}
static void __exit exit_hfsplus_fs(void)
{
unregister_filesystem(&hfsplus_fs_type);
/*
* Make sure all delayed rcu free inodes are flushed before we
* destroy cache.
*/
rcu_barrier();
hfsplus_destroy_attr_tree_cache();
kmem_cache_destroy(hfsplus_inode_cachep);
}
module_init(init_hfsplus_fs)
module_exit(exit_hfsplus_fs)
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