root/fs/hfsplus/hfsplus_fs.h
/* SPDX-License-Identifier: GPL-2.0 */
/*
 *  linux/include/linux/hfsplus_fs.h
 *
 * Copyright (C) 1999
 * Brad Boyer (flar@pants.nu)
 * (C) 2003 Ardis Technologies <roman@ardistech.com>
 *
 */

#ifndef _LINUX_HFSPLUS_FS_H
#define _LINUX_HFSPLUS_FS_H

#include <linux/fs.h>
#include <linux/mutex.h>
#include <linux/buffer_head.h>
#include <linux/blkdev.h>
#include <linux/fs_context.h>
#include "hfsplus_raw.h"

/* Runtime config options */
#define HFSPLUS_DEF_CR_TYPE    0x3F3F3F3F  /* '????' */

#define HFSPLUS_TYPE_DATA 0x00
#define HFSPLUS_TYPE_RSRC 0xFF

typedef int (*btree_keycmp)(const hfsplus_btree_key *,
                const hfsplus_btree_key *);

#define NODE_HASH_SIZE  256

/* B-tree mutex nested subclasses */
enum hfsplus_btree_mutex_classes {
        CATALOG_BTREE_MUTEX,
        EXTENTS_BTREE_MUTEX,
        ATTR_BTREE_MUTEX,
};

/* An HFS+ BTree held in memory */
struct hfs_btree {
        struct super_block *sb;
        struct inode *inode;
        btree_keycmp keycmp;

        u32 cnid;
        u32 root;
        u32 leaf_count;
        u32 leaf_head;
        u32 leaf_tail;
        u32 node_count;
        u32 free_nodes;
        u32 attributes;

        unsigned int node_size;
        unsigned int node_size_shift;
        unsigned int max_key_len;
        unsigned int depth;

        struct mutex tree_lock;

        unsigned int pages_per_bnode;
        spinlock_t hash_lock;
        struct hfs_bnode *node_hash[NODE_HASH_SIZE];
        int node_hash_cnt;
};

struct page;

/* An HFS+ BTree node in memory */
struct hfs_bnode {
        struct hfs_btree *tree;

        u32 prev;
        u32 this;
        u32 next;
        u32 parent;

        u16 num_recs;
        u8 type;
        u8 height;

        struct hfs_bnode *next_hash;
        unsigned long flags;
        wait_queue_head_t lock_wq;
        atomic_t refcnt;
        unsigned int page_offset;
        struct page *page[];
};

#define HFS_BNODE_LOCK          0
#define HFS_BNODE_ERROR         1
#define HFS_BNODE_NEW           2
#define HFS_BNODE_DIRTY         3
#define HFS_BNODE_DELETED       4

/*
 * Attributes file states
 */
#define HFSPLUS_EMPTY_ATTR_TREE         0
#define HFSPLUS_CREATING_ATTR_TREE      1
#define HFSPLUS_VALID_ATTR_TREE         2
#define HFSPLUS_FAILED_ATTR_TREE        3

/*
 * HFS+ superblock info (built from Volume Header on disk)
 */

struct hfsplus_vh;
struct hfs_btree;

struct hfsplus_sb_info {
        void *s_vhdr_buf;
        struct hfsplus_vh *s_vhdr;
        void *s_backup_vhdr_buf;
        struct hfsplus_vh *s_backup_vhdr;
        struct hfs_btree *ext_tree;
        struct hfs_btree *cat_tree;
        struct hfs_btree *attr_tree;
        atomic_t attr_tree_state;
        struct inode *alloc_file;
        struct inode *hidden_dir;
        struct nls_table *nls;

        /* Runtime variables */
        u32 blockoffset;
        u32 min_io_size;
        sector_t part_start;
        sector_t sect_count;
        int fs_shift;

        /* immutable data from the volume header */
        u32 alloc_blksz;
        int alloc_blksz_shift;
        u32 total_blocks;
        u32 data_clump_blocks, rsrc_clump_blocks;

        /* mutable data from the volume header, protected by alloc_mutex */
        u32 free_blocks;
        struct mutex alloc_mutex;

        /* mutable data from the volume header, protected by vh_mutex */
        u32 next_cnid;
        u32 file_count;
        u32 folder_count;
        struct mutex vh_mutex;

        /* Config options */
        u32 creator;
        u32 type;

        umode_t umask;
        kuid_t uid;
        kgid_t gid;

        int part, session;
        unsigned long flags;

        int work_queued;               /* non-zero delayed work is queued */
        struct delayed_work sync_work; /* FS sync delayed work */
        spinlock_t work_lock;          /* protects sync_work and work_queued */
        struct rcu_head rcu;
};

#define HFSPLUS_SB_WRITEBACKUP  0
#define HFSPLUS_SB_NODECOMPOSE  1
#define HFSPLUS_SB_FORCE        2
#define HFSPLUS_SB_HFSX         3
#define HFSPLUS_SB_CASEFOLD     4
#define HFSPLUS_SB_NOBARRIER    5
#define HFSPLUS_SB_UID          6
#define HFSPLUS_SB_GID          7

static inline struct hfsplus_sb_info *HFSPLUS_SB(struct super_block *sb)
{
        return sb->s_fs_info;
}


struct hfsplus_inode_info {
        atomic_t opencnt;

        /*
         * Extent allocation information, protected by extents_lock.
         */
        u32 first_blocks;
        u32 clump_blocks;
        u32 alloc_blocks;
        u32 cached_start;
        u32 cached_blocks;
        hfsplus_extent_rec first_extents;
        hfsplus_extent_rec cached_extents;
        unsigned int extent_state;
        struct mutex extents_lock;

        /*
         * Immutable data.
         */
        struct inode *rsrc_inode;
        __be32 create_date;

        /*
         * Protected by sbi->vh_mutex.
         */
        u32 linkid;

        /*
         * Accessed using atomic bitops.
         */
        unsigned long flags;

        /*
         * Protected by i_mutex.
         */
        sector_t fs_blocks;
        u8 userflags;           /* BSD user file flags */
        u32 subfolders;         /* Subfolder count (HFSX only) */
        struct list_head open_dir_list;
        spinlock_t open_dir_lock;
        loff_t phys_size;

        struct inode vfs_inode;
};

#define HFSPLUS_EXT_DIRTY       0x0001
#define HFSPLUS_EXT_NEW         0x0002

#define HFSPLUS_I_RSRC          0       /* represents a resource fork */
#define HFSPLUS_I_CAT_DIRTY     1       /* has changes in the catalog tree */
#define HFSPLUS_I_EXT_DIRTY     2       /* has changes in the extent tree */
#define HFSPLUS_I_ALLOC_DIRTY   3       /* has changes in the allocation file */
#define HFSPLUS_I_ATTR_DIRTY    4       /* has changes in the attributes tree */

#define HFSPLUS_IS_RSRC(inode) \
        test_bit(HFSPLUS_I_RSRC, &HFSPLUS_I(inode)->flags)

static inline struct hfsplus_inode_info *HFSPLUS_I(struct inode *inode)
{
        return container_of(inode, struct hfsplus_inode_info, vfs_inode);
}

/*
 * Mark an inode dirty, and also mark the btree in which the
 * specific type of metadata is stored.
 * For data or metadata that gets written back by into the catalog btree
 * by hfsplus_write_inode a plain mark_inode_dirty call is enough.
 */
static inline void hfsplus_mark_inode_dirty(struct inode *inode,
                unsigned int flag)
{
        set_bit(flag, &HFSPLUS_I(inode)->flags);
        mark_inode_dirty(inode);
}

struct hfs_find_data {
        /* filled by caller */
        hfsplus_btree_key *search_key;
        hfsplus_btree_key *key;
        /* filled by find */
        struct hfs_btree *tree;
        struct hfs_bnode *bnode;
        /* filled by findrec */
        int record;
        int keyoffset, keylength;
        int entryoffset, entrylength;
};

struct hfsplus_readdir_data {
        struct list_head list;
        struct file *file;
        struct hfsplus_cat_key key;
};

/*
 * Find minimum acceptible I/O size for an hfsplus sb.
 */
static inline unsigned short hfsplus_min_io_size(struct super_block *sb)
{
        return max_t(unsigned short, HFSPLUS_SB(sb)->min_io_size,
                     HFSPLUS_SECTOR_SIZE);
}

#define hfs_btree_open hfsplus_btree_open
#define hfs_btree_close hfsplus_btree_close
#define hfs_btree_write hfsplus_btree_write
#define hfs_bmap_reserve hfsplus_bmap_reserve
#define hfs_bmap_alloc hfsplus_bmap_alloc
#define hfs_bmap_free hfsplus_bmap_free
#define hfs_bnode_read hfsplus_bnode_read
#define hfs_bnode_read_u16 hfsplus_bnode_read_u16
#define hfs_bnode_read_u8 hfsplus_bnode_read_u8
#define hfs_bnode_read_key hfsplus_bnode_read_key
#define hfs_bnode_write hfsplus_bnode_write
#define hfs_bnode_write_u16 hfsplus_bnode_write_u16
#define hfs_bnode_clear hfsplus_bnode_clear
#define hfs_bnode_copy hfsplus_bnode_copy
#define hfs_bnode_move hfsplus_bnode_move
#define hfs_bnode_dump hfsplus_bnode_dump
#define hfs_bnode_unlink hfsplus_bnode_unlink
#define hfs_bnode_findhash hfsplus_bnode_findhash
#define hfs_bnode_find hfsplus_bnode_find
#define hfs_bnode_unhash hfsplus_bnode_unhash
#define hfs_bnode_free hfsplus_bnode_free
#define hfs_bnode_create hfsplus_bnode_create
#define hfs_bnode_get hfsplus_bnode_get
#define hfs_bnode_put hfsplus_bnode_put
#define hfs_brec_lenoff hfsplus_brec_lenoff
#define hfs_brec_keylen hfsplus_brec_keylen
#define hfs_brec_insert hfsplus_brec_insert
#define hfs_brec_remove hfsplus_brec_remove
#define hfs_find_init hfsplus_find_init
#define hfs_find_exit hfsplus_find_exit
#define __hfs_brec_find __hfsplus_brec_find
#define hfs_brec_find hfsplus_brec_find
#define hfs_brec_read hfsplus_brec_read
#define hfs_brec_goto hfsplus_brec_goto
#define hfs_part_find hfsplus_part_find

/*
 * hfs+-specific ioctl for making the filesystem bootable
 */
#define HFSPLUS_IOC_BLESS _IO('h', 0x80)

typedef int (*search_strategy_t)(struct hfs_bnode *,
                                struct hfs_find_data *,
                                int *, int *, int *);

/*
 * Functions in any *.c used in other files
 */

/* attributes.c */
int __init hfsplus_create_attr_tree_cache(void);
void hfsplus_destroy_attr_tree_cache(void);
int hfsplus_attr_bin_cmp_key(const hfsplus_btree_key *k1,
                             const hfsplus_btree_key *k2);
int hfsplus_attr_build_key(struct super_block *sb, hfsplus_btree_key *key,
                           u32 cnid, const char *name);
hfsplus_attr_entry *hfsplus_alloc_attr_entry(void);
void hfsplus_destroy_attr_entry(hfsplus_attr_entry *entry);
int hfsplus_find_attr(struct super_block *sb, u32 cnid, const char *name,
                      struct hfs_find_data *fd);
int hfsplus_attr_exists(struct inode *inode, const char *name);
int hfsplus_create_attr(struct inode *inode, const char *name,
                        const void *value, size_t size);
int hfsplus_delete_attr(struct inode *inode, const char *name);
int hfsplus_delete_all_attrs(struct inode *dir, u32 cnid);
int hfsplus_replace_attr(struct inode *inode,
                         const char *name,
                         const void *value, size_t size);

/* bitmap.c */
int hfsplus_block_allocate(struct super_block *sb, u32 size, u32 offset,
                           u32 *max);
int hfsplus_block_free(struct super_block *sb, u32 offset, u32 count);

/* btree.c */
u32 hfsplus_calc_btree_clump_size(u32 block_size, u32 node_size, u64 sectors,
                                  int file_id);
struct hfs_btree *hfs_btree_open(struct super_block *sb, u32 id);
void hfs_btree_close(struct hfs_btree *tree);
int hfs_btree_write(struct hfs_btree *tree);
int hfs_bmap_reserve(struct hfs_btree *tree, u32 rsvd_nodes);
struct hfs_bnode *hfs_bmap_alloc(struct hfs_btree *tree);
void hfs_bmap_free(struct hfs_bnode *node);

/* bnode.c */
void hfs_bnode_read(struct hfs_bnode *node, void *buf, u32 off, u32 len);
u16 hfs_bnode_read_u16(struct hfs_bnode *node, u32 off);
u8 hfs_bnode_read_u8(struct hfs_bnode *node, u32 off);
void hfs_bnode_read_key(struct hfs_bnode *node, void *key, u32 off);
void hfs_bnode_write(struct hfs_bnode *node, void *buf, u32 off, u32 len);
void hfs_bnode_write_u16(struct hfs_bnode *node, u32 off, u16 data);
void hfs_bnode_clear(struct hfs_bnode *node, u32 off, u32 len);
void hfs_bnode_copy(struct hfs_bnode *dst_node, u32 dst,
                    struct hfs_bnode *src_node, u32 src, u32 len);
void hfs_bnode_move(struct hfs_bnode *node, u32 dst, u32 src, u32 len);
void hfs_bnode_dump(struct hfs_bnode *node);
void hfs_bnode_unlink(struct hfs_bnode *node);
struct hfs_bnode *hfs_bnode_findhash(struct hfs_btree *tree, u32 cnid);
void hfs_bnode_unhash(struct hfs_bnode *node);
struct hfs_bnode *hfs_bnode_find(struct hfs_btree *tree, u32 num);
void hfs_bnode_free(struct hfs_bnode *node);
struct hfs_bnode *hfs_bnode_create(struct hfs_btree *tree, u32 num);
void hfs_bnode_get(struct hfs_bnode *node);
void hfs_bnode_put(struct hfs_bnode *node);
bool hfs_bnode_need_zeroout(struct hfs_btree *tree);

/* brec.c */
u16 hfs_brec_lenoff(struct hfs_bnode *node, u16 rec, u16 *off);
u16 hfs_brec_keylen(struct hfs_bnode *node, u16 rec);
int hfs_brec_insert(struct hfs_find_data *fd, void *entry, u32 entry_len);
int hfs_brec_remove(struct hfs_find_data *fd);

/* bfind.c */
int hfs_find_init(struct hfs_btree *tree, struct hfs_find_data *fd);
void hfs_find_exit(struct hfs_find_data *fd);
int hfs_find_1st_rec_by_cnid(struct hfs_bnode *bnode, struct hfs_find_data *fd,
                             int *begin, int *end, int *cur_rec);
int hfs_find_rec_by_key(struct hfs_bnode *bnode, struct hfs_find_data *fd,
                        int *begin, int *end, int *cur_rec);
int __hfs_brec_find(struct hfs_bnode *bnode, struct hfs_find_data *fd,
                    search_strategy_t rec_found);
int hfs_brec_find(struct hfs_find_data *fd, search_strategy_t do_key_compare);
int hfs_brec_read(struct hfs_find_data *fd, void *rec, u32 rec_len);
int hfs_brec_goto(struct hfs_find_data *fd, int cnt);

/* catalog.c */
int hfsplus_cat_case_cmp_key(const hfsplus_btree_key *k1,
                             const hfsplus_btree_key *k2);
int hfsplus_cat_bin_cmp_key(const hfsplus_btree_key *k1,
                            const hfsplus_btree_key *k2);
int hfsplus_cat_build_key(struct super_block *sb, hfsplus_btree_key *key,
                           u32 parent, const struct qstr *str);
void hfsplus_cat_build_key_with_cnid(struct super_block *sb,
                                     hfsplus_btree_key *key, u32 parent);
void hfsplus_cat_set_perms(struct inode *inode, struct hfsplus_perm *perms);
int hfsplus_find_cat(struct super_block *sb, u32 cnid,
                     struct hfs_find_data *fd);
int hfsplus_create_cat(u32 cnid, struct inode *dir, const struct qstr *str,
                       struct inode *inode);
int hfsplus_delete_cat(u32 cnid, struct inode *dir, const struct qstr *str);
int hfsplus_rename_cat(u32 cnid, struct inode *src_dir, const struct qstr *src_name,
                       struct inode *dst_dir, const struct qstr *dst_name);

/* dir.c */
extern const struct inode_operations hfsplus_dir_inode_operations;
extern const struct file_operations hfsplus_dir_operations;

/* extents.c */
int hfsplus_ext_cmp_key(const hfsplus_btree_key *k1,
                        const hfsplus_btree_key *k2);
int hfsplus_ext_write_extent(struct inode *inode);
int hfsplus_get_block(struct inode *inode, sector_t iblock,
                      struct buffer_head *bh_result, int create);
int hfsplus_free_fork(struct super_block *sb, u32 cnid,
                      struct hfsplus_fork_raw *fork, int type);
int hfsplus_file_extend(struct inode *inode, bool zeroout);
void hfsplus_file_truncate(struct inode *inode);

/* inode.c */
extern const struct address_space_operations hfsplus_aops;
extern const struct address_space_operations hfsplus_btree_aops;
extern const struct dentry_operations hfsplus_dentry_operations;

int hfsplus_write_begin(const struct kiocb *iocb,
                        struct address_space *mapping,
                        loff_t pos, unsigned len, struct folio **foliop,
                        void **fsdata);
struct inode *hfsplus_new_inode(struct super_block *sb, struct inode *dir,
                                umode_t mode);
void hfsplus_delete_inode(struct inode *inode);
void hfsplus_inode_read_fork(struct inode *inode,
                             struct hfsplus_fork_raw *fork);
void hfsplus_inode_write_fork(struct inode *inode,
                              struct hfsplus_fork_raw *fork);
int hfsplus_cat_read_inode(struct inode *inode, struct hfs_find_data *fd);
int hfsplus_cat_write_inode(struct inode *inode);
int hfsplus_getattr(struct mnt_idmap *idmap, const struct path *path,
                    struct kstat *stat, u32 request_mask,
                    unsigned int query_flags);
int hfsplus_file_fsync(struct file *file, loff_t start, loff_t end,
                       int datasync);
int hfsplus_fileattr_get(struct dentry *dentry, struct file_kattr *fa);
int hfsplus_fileattr_set(struct mnt_idmap *idmap,
                         struct dentry *dentry, struct file_kattr *fa);

/* ioctl.c */
long hfsplus_ioctl(struct file *filp, unsigned int cmd, unsigned long arg);

/* options.c */
void hfsplus_fill_defaults(struct hfsplus_sb_info *opts);
int hfsplus_parse_param(struct fs_context *fc, struct fs_parameter *param);
int hfsplus_show_options(struct seq_file *seq, struct dentry *root);

/* part_tbl.c */
int hfs_part_find(struct super_block *sb, sector_t *part_start,
                  sector_t *part_size);

/* super.c */
struct inode *hfsplus_iget(struct super_block *sb, unsigned long ino);
void hfsplus_mark_mdb_dirty(struct super_block *sb);
void hfsplus_prepare_volume_header_for_commit(struct hfsplus_vh *vhdr);
int hfsplus_commit_superblock(struct super_block *sb);

/* tables.c */
extern u16 hfsplus_case_fold_table[];
extern u16 hfsplus_decompose_table[];
extern u16 hfsplus_compose_table[];

/* unicode.c */
int hfsplus_strcasecmp(const struct hfsplus_unistr *s1,
                       const struct hfsplus_unistr *s2);
int hfsplus_strcmp(const struct hfsplus_unistr *s1,
                   const struct hfsplus_unistr *s2);
int hfsplus_uni2asc_str(struct super_block *sb,
                        const struct hfsplus_unistr *ustr, char *astr,
                        int *len_p);
int hfsplus_uni2asc_xattr_str(struct super_block *sb,
                              const struct hfsplus_attr_unistr *ustr,
                              char *astr, int *len_p);
int hfsplus_asc2uni(struct super_block *sb, struct hfsplus_unistr *ustr,
                    int max_unistr_len, const char *astr, int len);
int hfsplus_hash_dentry(const struct dentry *dentry, struct qstr *str);
int hfsplus_compare_dentry(const struct dentry *dentry, unsigned int len,
                           const char *str, const struct qstr *name);

/* wrapper.c */
int hfsplus_submit_bio(struct super_block *sb, sector_t sector, void *buf,
                       void **data, blk_opf_t opf);
int hfsplus_read_wrapper(struct super_block *sb);

/*
 * time helpers: convert between 1904-base and 1970-base timestamps
 *
 * HFS+ implementations are highly inconsistent, this one matches the
 * traditional behavior of 64-bit Linux, giving the most useful
 * time range between 1970 and 2106, by treating any on-disk timestamp
 * under HFSPLUS_UTC_OFFSET (Jan 1 1970) as a time between 2040 and 2106.
 */
#define HFSPLUS_UTC_OFFSET 2082844800U

static inline time64_t __hfsp_mt2ut(__be32 mt)
{
        time64_t ut = (u32)(be32_to_cpu(mt) - HFSPLUS_UTC_OFFSET);

        return ut;
}

static inline __be32 __hfsp_ut2mt(time64_t ut)
{
        return cpu_to_be32(lower_32_bits(ut) + HFSPLUS_UTC_OFFSET);
}

static inline enum hfsplus_btree_mutex_classes
hfsplus_btree_lock_class(struct hfs_btree *tree)
{
        enum hfsplus_btree_mutex_classes class;

        switch (tree->cnid) {
        case HFSPLUS_CAT_CNID:
                class = CATALOG_BTREE_MUTEX;
                break;
        case HFSPLUS_EXT_CNID:
                class = EXTENTS_BTREE_MUTEX;
                break;
        case HFSPLUS_ATTR_CNID:
                class = ATTR_BTREE_MUTEX;
                break;
        default:
                BUG();
        }
        return class;
}

static inline
bool is_bnode_offset_valid(struct hfs_bnode *node, u32 off)
{
        bool is_valid = off < node->tree->node_size;

        if (!is_valid) {
                pr_err("requested invalid offset: "
                       "NODE: id %u, type %#x, height %u, "
                       "node_size %u, offset %u\n",
                       node->this, node->type, node->height,
                       node->tree->node_size, off);
        }

        return is_valid;
}

static inline
u32 check_and_correct_requested_length(struct hfs_bnode *node, u32 off, u32 len)
{
        unsigned int node_size;

        if (!is_bnode_offset_valid(node, off))
                return 0;

        node_size = node->tree->node_size;

        if ((off + len) > node_size) {
                u32 new_len = node_size - off;

                pr_err("requested length has been corrected: "
                       "NODE: id %u, type %#x, height %u, "
                       "node_size %u, offset %u, "
                       "requested_len %u, corrected_len %u\n",
                       node->this, node->type, node->height,
                       node->tree->node_size, off, len, new_len);

                return new_len;
        }

        return len;
}

/* compatibility */
#define hfsp_mt2ut(t)           (struct timespec64){ .tv_sec = __hfsp_mt2ut(t) }
#define hfsp_ut2mt(t)           __hfsp_ut2mt((t).tv_sec)
#define hfsp_now2mt()           __hfsp_ut2mt(ktime_get_real_seconds())

#endif