fs/hpfs/hpfs_fn.h - linux - Git at Google

 /* SPDX-License-Identifier: GPL-2.0 */
 /*
  *  linux/fs/hpfs/hpfs_fn.h
  *
  *  Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
  *
  *  function headers
  */

 //#define DBG
 //#define DEBUG_LOCKS
 #ifdef pr_fmt
 #undef pr_fmt
 #endif

 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

 #include <linux/mutex.h>
 #include <linux/pagemap.h>
 #include <linux/buffer_head.h>
 #include <linux/slab.h>
 #include <linux/sched/signal.h>
 #include <linux/blkdev.h>
 #include <asm/unaligned.h>

 #include "hpfs.h"

 #define EIOERROR  EIO
 #define EFSERROR  EUCLEAN

 #define ANODE_ALLOC_FWD	512
 #define FNODE_ALLOC_FWD	0
 #define ALLOC_FWD_MIN	16
 #define ALLOC_FWD_MAX	128
 #define ALLOC_M		1
 #define FNODE_RD_AHEAD	16
 #define ANODE_RD_AHEAD	0
 #define DNODE_RD_AHEAD	72
 #define COUNT_RD_AHEAD	62

 #define FREE_DNODES_ADD	58
 #define FREE_DNODES_DEL	29

 #define CHKCOND(x,y) if (!(x)) printk y

 struct hpfs_inode_info {
 	loff_t mmu_private;
 	ino_t i_parent_dir;	/* (directories) gives fnode of parent dir */
 	unsigned i_dno;		/* (directories) root dnode */
 	unsigned i_dpos;	/* (directories) temp for readdir */
 	unsigned i_dsubdno;	/* (directories) temp for readdir */
 	unsigned i_file_sec;	/* (files) minimalist cache of alloc info */
 	unsigned i_disk_sec;	/* (files) minimalist cache of alloc info */
 	unsigned i_n_secs;	/* (files) minimalist cache of alloc info */
 	unsigned i_ea_size;	/* size of extended attributes */
 	unsigned i_ea_mode : 1;	/* file's permission is stored in ea */
 	unsigned i_ea_uid : 1;	/* file's uid is stored in ea */
 	unsigned i_ea_gid : 1;	/* file's gid is stored in ea */
 	unsigned i_dirty : 1;
 	loff_t **i_rddir_off;
 	struct inode vfs_inode;
 };

 struct hpfs_sb_info {
 	struct mutex hpfs_mutex;	/* global hpfs lock */
 	ino_t sb_root;			/* inode number of root dir */
 	unsigned sb_fs_size;		/* file system size, sectors */
 	unsigned sb_bitmaps;		/* sector number of bitmap list */
 	unsigned sb_dirband_start;	/* directory band start sector */
 	unsigned sb_dirband_size;	/* directory band size, dnodes */
 	unsigned sb_dmap;		/* sector number of dnode bit map */
 	unsigned sb_n_free;		/* free blocks for statfs, or -1 */
 	unsigned sb_n_free_dnodes;	/* free dnodes for statfs, or -1 */
 	kuid_t sb_uid;			/* uid from mount options */
 	kgid_t sb_gid;			/* gid from mount options */
 	umode_t sb_mode;		/* mode from mount options */
 	unsigned sb_eas : 2;		/* eas: 0-ignore, 1-ro, 2-rw */
 	unsigned sb_err : 2;		/* on errs: 0-cont, 1-ro, 2-panic */
 	unsigned sb_chk : 2;		/* checks: 0-no, 1-normal, 2-strict */
 	unsigned sb_lowercase : 1;	/* downcase filenames hackery */
 	unsigned sb_was_error : 1;	/* there was an error, set dirty flag */
 	unsigned sb_chkdsk : 2;		/* chkdsk: 0-no, 1-on errs, 2-allways */
 	unsigned char *sb_cp_table;	/* code page tables: */
 					/* 	128 bytes uppercasing table & */
 					/*	128 bytes lowercasing table */
 	__le32 *sb_bmp_dir;		/* main bitmap directory */
 	unsigned sb_c_bitmap;		/* current bitmap */
 	unsigned sb_max_fwd_alloc;	/* max forwad allocation */
 	int sb_timeshift;
 	struct rcu_head rcu;

 	unsigned n_hotfixes;
 	secno hotfix_from[256];
 	secno hotfix_to[256];
 };

 /* Four 512-byte buffers and the 2k block obtained by concatenating them */

 struct quad_buffer_head {
 	struct buffer_head *bh[4];
 	void *data;
 };

 /* The b-tree down pointer from a dir entry */

 static inline dnode_secno de_down_pointer (struct hpfs_dirent *de)
 {
   CHKCOND(de->down,("HPFS: de_down_pointer: !de->down\n"));
   return le32_to_cpu(*(__le32 *) ((void *) de + le16_to_cpu(de->length) - 4));
 }

 /* The first dir entry in a dnode */

 static inline struct hpfs_dirent *dnode_first_de (struct dnode *dnode)
 {
   return (void *) dnode->dirent;
 }

 /* The end+1 of the dir entries */

 static inline struct hpfs_dirent *dnode_end_de (struct dnode *dnode)
 {
   CHKCOND(le32_to_cpu(dnode->first_free)>=0x14 && le32_to_cpu(dnode->first_free)<=0xa00,("HPFS: dnode_end_de: dnode->first_free = %x\n",(unsigned)le32_to_cpu(dnode->first_free)));
   return (void *) dnode + le32_to_cpu(dnode->first_free);
 }

 /* The dir entry after dir entry de */

 static inline struct hpfs_dirent *de_next_de (struct hpfs_dirent *de)
 {
   CHKCOND(le16_to_cpu(de->length)>=0x20 && le16_to_cpu(de->length)<0x800,("HPFS: de_next_de: de->length = %x\n",(unsigned)le16_to_cpu(de->length)));
   return (void *) de + le16_to_cpu(de->length);
 }

 static inline struct extended_attribute *fnode_ea(struct fnode *fnode)
 {
 	return (struct extended_attribute *)((char *)fnode + le16_to_cpu(fnode->ea_offs) + le16_to_cpu(fnode->acl_size_s));
 }

 static inline struct extended_attribute *fnode_end_ea(struct fnode *fnode)
 {
 	return (struct extended_attribute *)((char *)fnode + le16_to_cpu(fnode->ea_offs) + le16_to_cpu(fnode->acl_size_s) + le16_to_cpu(fnode->ea_size_s));
 }

 static unsigned ea_valuelen(struct extended_attribute *ea)
 {
 	return ea->valuelen_lo + 256 * ea->valuelen_hi;
 }

 static inline struct extended_attribute *next_ea(struct extended_attribute *ea)
 {
 	return (struct extended_attribute *)((char *)ea + 5 + ea->namelen + ea_valuelen(ea));
 }

 static inline secno ea_sec(struct extended_attribute *ea)
 {
 	return le32_to_cpu(get_unaligned((__le32 *)((char *)ea + 9 + ea->namelen)));
 }

 static inline secno ea_len(struct extended_attribute *ea)
 {
 	return le32_to_cpu(get_unaligned((__le32 *)((char *)ea + 5 + ea->namelen)));
 }

 static inline char *ea_data(struct extended_attribute *ea)
 {
 	return (char *)((char *)ea + 5 + ea->namelen);
 }

 static inline unsigned de_size(int namelen, secno down_ptr)
 {
 	return ((0x1f + namelen + 3) & ~3) + (down_ptr ? 4 : 0);
 }

 static inline void copy_de(struct hpfs_dirent *dst, struct hpfs_dirent *src)
 {
 	int a;
 	int n;
 	if (!dst || !src) return;
 	a = dst->down;
 	n = dst->not_8x3;
 	memcpy((char *)dst + 2, (char *)src + 2, 28);
 	dst->down = a;
 	dst->not_8x3 = n;
 }

 static inline unsigned tstbits(__le32 *bmp, unsigned b, unsigned n)
 {
 	int i;
 	if ((b >= 0x4000) || (b + n - 1 >= 0x4000)) return n;
 	if (!((le32_to_cpu(bmp[(b & 0x3fff) >> 5]) >> (b & 0x1f)) & 1)) return 1;
 	for (i = 1; i < n; i++)
 		if (!((le32_to_cpu(bmp[((b+i) & 0x3fff) >> 5]) >> ((b+i) & 0x1f)) & 1))
 			return i + 1;
 	return 0;
 }

 /* alloc.c */

 int hpfs_chk_sectors(struct super_block *, secno, int, char *);
 secno hpfs_alloc_sector(struct super_block *, secno, unsigned, int);
 int hpfs_alloc_if_possible(struct super_block *, secno);
 void hpfs_free_sectors(struct super_block *, secno, unsigned);
 int hpfs_check_free_dnodes(struct super_block *, int);
 void hpfs_free_dnode(struct super_block *, secno);
 struct dnode *hpfs_alloc_dnode(struct super_block *, secno, dnode_secno *, struct quad_buffer_head *);
 struct fnode *hpfs_alloc_fnode(struct super_block *, secno, fnode_secno *, struct buffer_head **);
 struct anode *hpfs_alloc_anode(struct super_block *, secno, anode_secno *, struct buffer_head **);
 int hpfs_trim_fs(struct super_block *, u64, u64, u64, unsigned *);

 /* anode.c */

 secno hpfs_bplus_lookup(struct super_block *, struct inode *, struct bplus_header *, unsigned, struct buffer_head *);
 secno hpfs_add_sector_to_btree(struct super_block *, secno, int, unsigned);
 void hpfs_remove_btree(struct super_block *, struct bplus_header *);
 int hpfs_ea_read(struct super_block *, secno, int, unsigned, unsigned, char *);
 int hpfs_ea_write(struct super_block *, secno, int, unsigned, unsigned, const char *);
 void hpfs_ea_remove(struct super_block *, secno, int, unsigned);
 void hpfs_truncate_btree(struct super_block *, secno, int, unsigned);
 void hpfs_remove_fnode(struct super_block *, fnode_secno fno);

 /* buffer.c */

 secno hpfs_search_hotfix_map(struct super_block *s, secno sec);
 unsigned hpfs_search_hotfix_map_for_range(struct super_block *s, secno sec, unsigned n);
 void hpfs_prefetch_sectors(struct super_block *, unsigned, int);
 void *hpfs_map_sector(struct super_block *, unsigned, struct buffer_head **, int);
 void *hpfs_get_sector(struct super_block *, unsigned, struct buffer_head **);
 void *hpfs_map_4sectors(struct super_block *, unsigned, struct quad_buffer_head *, int);
 void *hpfs_get_4sectors(struct super_block *, unsigned, struct quad_buffer_head *);
 void hpfs_brelse4(struct quad_buffer_head *);
 void hpfs_mark_4buffers_dirty(struct quad_buffer_head *);

 /* dentry.c */

 extern const struct dentry_operations hpfs_dentry_operations;

 /* dir.c */

 struct dentry *hpfs_lookup(struct inode *, struct dentry *, unsigned int);
 extern const struct file_operations hpfs_dir_ops;

 /* dnode.c */

 int hpfs_add_pos(struct inode *, loff_t *);
 void hpfs_del_pos(struct inode *, loff_t *);
 struct hpfs_dirent *hpfs_add_de(struct super_block *, struct dnode *,
 				const unsigned char *, unsigned, secno);
 int hpfs_add_dirent(struct inode *, const unsigned char *, unsigned,
 		    struct hpfs_dirent *);
 int hpfs_remove_dirent(struct inode *, dnode_secno, struct hpfs_dirent *, struct quad_buffer_head *, int);
 void hpfs_count_dnodes(struct super_block *, dnode_secno, int *, int *, int *);
 dnode_secno hpfs_de_as_down_as_possible(struct super_block *, dnode_secno dno);
 struct hpfs_dirent *map_pos_dirent(struct inode *, loff_t *, struct quad_buffer_head *);
 struct hpfs_dirent *map_dirent(struct inode *, dnode_secno,
 			       const unsigned char *, unsigned, dnode_secno *,
 			       struct quad_buffer_head *);
 void hpfs_remove_dtree(struct super_block *, dnode_secno);
 struct hpfs_dirent *map_fnode_dirent(struct super_block *, fnode_secno, struct fnode *, struct quad_buffer_head *);

 /* ea.c */

 void hpfs_ea_ext_remove(struct super_block *, secno, int, unsigned);
 int hpfs_read_ea(struct super_block *, struct fnode *, char *, char *, int);
 char *hpfs_get_ea(struct super_block *, struct fnode *, char *, int *);
 void hpfs_set_ea(struct inode *, struct fnode *, const char *,
 		 const char *, int);

 /* file.c */

 int hpfs_file_fsync(struct file *, loff_t, loff_t, int);
 void hpfs_truncate(struct inode *);
 extern const struct file_operations hpfs_file_ops;
 extern const struct inode_operations hpfs_file_iops;
 extern const struct address_space_operations hpfs_aops;

 /* inode.c */

 void hpfs_init_inode(struct inode *);
 void hpfs_read_inode(struct inode *);
 void hpfs_write_inode(struct inode *);
 void hpfs_write_inode_nolock(struct inode *);
 int hpfs_setattr(struct user_namespace *, struct dentry *, struct iattr *);
 void hpfs_write_if_changed(struct inode *);
 void hpfs_evict_inode(struct inode *);

 /* map.c */

 __le32 *hpfs_map_dnode_bitmap(struct super_block *, struct quad_buffer_head *);
 __le32 *hpfs_map_bitmap(struct super_block *, unsigned, struct quad_buffer_head *, char *);
 void hpfs_prefetch_bitmap(struct super_block *, unsigned);
 unsigned char *hpfs_load_code_page(struct super_block *, secno);
 __le32 *hpfs_load_bitmap_directory(struct super_block *, secno bmp);
 void hpfs_load_hotfix_map(struct super_block *s, struct hpfs_spare_block *spareblock);
 struct fnode *hpfs_map_fnode(struct super_block *s, ino_t, struct buffer_head **);
 struct anode *hpfs_map_anode(struct super_block *s, anode_secno, struct buffer_head **);
 struct dnode *hpfs_map_dnode(struct super_block *s, dnode_secno, struct quad_buffer_head *);
 dnode_secno hpfs_fnode_dno(struct super_block *s, ino_t ino);

 /* name.c */

 unsigned char hpfs_upcase(unsigned char *, unsigned char);
 int hpfs_chk_name(const unsigned char *, unsigned *);
 unsigned char *hpfs_translate_name(struct super_block *, unsigned char *, unsigned, int, int);
 int hpfs_compare_names(struct super_block *, const unsigned char *, unsigned,
 		       const unsigned char *, unsigned, int);
 int hpfs_is_name_long(const unsigned char *, unsigned);
 void hpfs_adjust_length(const unsigned char *, unsigned *);

 /* namei.c */

 extern const struct inode_operations hpfs_dir_iops;
 extern const struct address_space_operations hpfs_symlink_aops;

 static inline struct hpfs_inode_info *hpfs_i(struct inode *inode)
 {
 	return container_of(inode, struct hpfs_inode_info, vfs_inode);
 }

 static inline struct hpfs_sb_info *hpfs_sb(struct super_block *sb)
 {
 	return sb->s_fs_info;
 }

 /* super.c */

 __printf(2, 3)
 void hpfs_error(struct super_block *, const char *, ...);
 int hpfs_stop_cycles(struct super_block *, int, int *, int *, char *);
 unsigned hpfs_get_free_dnodes(struct super_block *);
 long hpfs_ioctl(struct file *file, unsigned cmd, unsigned long arg);

 /*
  * local time (HPFS) to GMT (Unix)
  */

 static inline time64_t local_to_gmt(struct super_block *s, time64_t t)
 {
 	extern struct timezone sys_tz;
 	return t + sys_tz.tz_minuteswest * 60 + hpfs_sb(s)->sb_timeshift;
 }

 static inline time32_t gmt_to_local(struct super_block *s, time64_t t)
 {
 	extern struct timezone sys_tz;
 	return t - sys_tz.tz_minuteswest * 60 - hpfs_sb(s)->sb_timeshift;
 }

 static inline time32_t local_get_seconds(struct super_block *s)
 {
 	return gmt_to_local(s, ktime_get_real_seconds());
 }

 /*
  * Locking:
  *
  * hpfs_lock() locks the whole filesystem. It must be taken
  * on any method called by the VFS.
  *
  * We don't do any per-file locking anymore, it is hard to
  * review and HPFS is not performance-sensitive anyway.
  */
 static inline void hpfs_lock(struct super_block *s)
 {
 	struct hpfs_sb_info *sbi = hpfs_sb(s);
 	mutex_lock(&sbi->hpfs_mutex);
 }

 static inline void hpfs_unlock(struct super_block *s)
 {
 	struct hpfs_sb_info *sbi = hpfs_sb(s);
 	mutex_unlock(&sbi->hpfs_mutex);
 }

 static inline void hpfs_lock_assert(struct super_block *s)
 {
 	struct hpfs_sb_info *sbi = hpfs_sb(s);
 	WARN_ON(!mutex_is_locked(&sbi->hpfs_mutex));
 }
	/* SPDX-License-Identifier: GPL-2.0 */
	/*
	* linux/fs/hpfs/hpfs_fn.h
	*
	* Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
	*
	* function headers
	*/

	//#define DBG
	//#define DEBUG_LOCKS
	#ifdef pr_fmt
	#undef pr_fmt
	#endif

	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

	#include <linux/mutex.h>
	#include <linux/pagemap.h>
	#include <linux/buffer_head.h>
	#include <linux/slab.h>
	#include <linux/sched/signal.h>
	#include <linux/blkdev.h>
	#include <asm/unaligned.h>

	#include "hpfs.h"

	#define EIOERROR EIO
	#define EFSERROR EUCLEAN

	#define ANODE_ALLOC_FWD 512
	#define FNODE_ALLOC_FWD 0
	#define ALLOC_FWD_MIN 16
	#define ALLOC_FWD_MAX 128
	#define ALLOC_M 1
	#define FNODE_RD_AHEAD 16
	#define ANODE_RD_AHEAD 0
	#define DNODE_RD_AHEAD 72
	#define COUNT_RD_AHEAD 62

	#define FREE_DNODES_ADD 58
	#define FREE_DNODES_DEL 29

	#define CHKCOND(x,y) if (!(x)) printk y

	struct hpfs_inode_info {
	loff_t mmu_private;
	ino_t i_parent_dir; /* (directories) gives fnode of parent dir */
	unsigned i_dno; /* (directories) root dnode */
	unsigned i_dpos; /* (directories) temp for readdir */
	unsigned i_dsubdno; /* (directories) temp for readdir */
	unsigned i_file_sec; /* (files) minimalist cache of alloc info */
	unsigned i_disk_sec; /* (files) minimalist cache of alloc info */
	unsigned i_n_secs; /* (files) minimalist cache of alloc info */
	unsigned i_ea_size; /* size of extended attributes */
	unsigned i_ea_mode : 1; /* file's permission is stored in ea */
	unsigned i_ea_uid : 1; /* file's uid is stored in ea */
	unsigned i_ea_gid : 1; /* file's gid is stored in ea */
	unsigned i_dirty : 1;
	loff_t **i_rddir_off;
	struct inode vfs_inode;
	};

	struct hpfs_sb_info {
	struct mutex hpfs_mutex; /* global hpfs lock */
	ino_t sb_root; /* inode number of root dir */
	unsigned sb_fs_size; /* file system size, sectors */
	unsigned sb_bitmaps; /* sector number of bitmap list */
	unsigned sb_dirband_start; /* directory band start sector */
	unsigned sb_dirband_size; /* directory band size, dnodes */
	unsigned sb_dmap; /* sector number of dnode bit map */
	unsigned sb_n_free; /* free blocks for statfs, or -1 */
	unsigned sb_n_free_dnodes; /* free dnodes for statfs, or -1 */
	kuid_t sb_uid; /* uid from mount options */
	kgid_t sb_gid; /* gid from mount options */
	umode_t sb_mode; /* mode from mount options */
	unsigned sb_eas : 2; /* eas: 0-ignore, 1-ro, 2-rw */
	unsigned sb_err : 2; /* on errs: 0-cont, 1-ro, 2-panic */
	unsigned sb_chk : 2; /* checks: 0-no, 1-normal, 2-strict */
	unsigned sb_lowercase : 1; /* downcase filenames hackery */
	unsigned sb_was_error : 1; /* there was an error, set dirty flag */
	unsigned sb_chkdsk : 2; /* chkdsk: 0-no, 1-on errs, 2-allways */
	unsigned char sb_cp_table; / code page tables: */
	/* 128 bytes uppercasing table & */
	/* 128 bytes lowercasing table */
	__le32 sb_bmp_dir; / main bitmap directory */
	unsigned sb_c_bitmap; /* current bitmap */
	unsigned sb_max_fwd_alloc; /* max forwad allocation */
	int sb_timeshift;
	struct rcu_head rcu;

	unsigned n_hotfixes;
	secno hotfix_from[256];
	secno hotfix_to[256];
	};

	/* Four 512-byte buffers and the 2k block obtained by concatenating them */

	struct quad_buffer_head {
	struct buffer_head *bh[4];
	void *data;
	};

	/* The b-tree down pointer from a dir entry */

	static inline dnode_secno de_down_pointer (struct hpfs_dirent *de)
	{
	CHKCOND(de->down,("HPFS: de_down_pointer: !de->down\n"));
	return le32_to_cpu((__le32 ) ((void *) de + le16_to_cpu(de->length) - 4));
	}

	/* The first dir entry in a dnode */

	static inline struct hpfs_dirent dnode_first_de (struct dnode dnode)
	{
	return (void *) dnode->dirent;
	}

	/* The end+1 of the dir entries */

	static inline struct hpfs_dirent dnode_end_de (struct dnode dnode)
	{
	CHKCOND(le32_to_cpu(dnode->first_free)>=0x14 && le32_to_cpu(dnode->first_free)<=0xa00,("HPFS: dnode_end_de: dnode->first_free = %x\n",(unsigned)le32_to_cpu(dnode->first_free)));
	return (void *) dnode + le32_to_cpu(dnode->first_free);
	}

	/* The dir entry after dir entry de */

	static inline struct hpfs_dirent de_next_de (struct hpfs_dirent de)
	{
	CHKCOND(le16_to_cpu(de->length)>=0x20 && le16_to_cpu(de->length)<0x800,("HPFS: de_next_de: de->length = %x\n",(unsigned)le16_to_cpu(de->length)));
	return (void *) de + le16_to_cpu(de->length);
	}

	static inline struct extended_attribute fnode_ea(struct fnode fnode)
	{
	return (struct extended_attribute )((char )fnode + le16_to_cpu(fnode->ea_offs) + le16_to_cpu(fnode->acl_size_s));
	}

	static inline struct extended_attribute fnode_end_ea(struct fnode fnode)
	{
	return (struct extended_attribute )((char )fnode + le16_to_cpu(fnode->ea_offs) + le16_to_cpu(fnode->acl_size_s) + le16_to_cpu(fnode->ea_size_s));
	}

	static unsigned ea_valuelen(struct extended_attribute *ea)
	{
	return ea->valuelen_lo + 256 * ea->valuelen_hi;
	}

	static inline struct extended_attribute next_ea(struct extended_attribute ea)
	{
	return (struct extended_attribute )((char )ea + 5 + ea->namelen + ea_valuelen(ea));
	}

	static inline secno ea_sec(struct extended_attribute *ea)
	{
	return le32_to_cpu(get_unaligned((__le32 )((char )ea + 9 + ea->namelen)));
	}

	static inline secno ea_len(struct extended_attribute *ea)
	{
	return le32_to_cpu(get_unaligned((__le32 )((char )ea + 5 + ea->namelen)));
	}

	static inline char ea_data(struct extended_attribute ea)
	{
	return (char )((char )ea + 5 + ea->namelen);
	}

	static inline unsigned de_size(int namelen, secno down_ptr)
	{
	return ((0x1f + namelen + 3) & ~3) + (down_ptr ? 4 : 0);
	}

	static inline void copy_de(struct hpfs_dirent dst, struct hpfs_dirent src)
	{
	int a;
	int n;
	if (!dst \|\| !src) return;
	a = dst->down;
	n = dst->not_8x3;
	memcpy((char )dst + 2, (char )src + 2, 28);
	dst->down = a;
	dst->not_8x3 = n;
	}

	static inline unsigned tstbits(__le32 *bmp, unsigned b, unsigned n)
	{
	int i;
	if ((b >= 0x4000) \|\| (b + n - 1 >= 0x4000)) return n;
	if (!((le32_to_cpu(bmp[(b & 0x3fff) >> 5]) >> (b & 0x1f)) & 1)) return 1;
	for (i = 1; i < n; i++)
	if (!((le32_to_cpu(bmp[((b+i) & 0x3fff) >> 5]) >> ((b+i) & 0x1f)) & 1))
	return i + 1;
	return 0;
	}

	/* alloc.c */

	int hpfs_chk_sectors(struct super_block , secno, int, char );
	secno hpfs_alloc_sector(struct super_block *, secno, unsigned, int);
	int hpfs_alloc_if_possible(struct super_block *, secno);
	void hpfs_free_sectors(struct super_block *, secno, unsigned);
	int hpfs_check_free_dnodes(struct super_block *, int);
	void hpfs_free_dnode(struct super_block *, secno);
	struct dnode hpfs_alloc_dnode(struct super_block , secno, dnode_secno , struct quad_buffer_head );
	struct fnode hpfs_alloc_fnode(struct super_block , secno, fnode_secno , struct buffer_head *);
	struct anode hpfs_alloc_anode(struct super_block , secno, anode_secno , struct buffer_head *);
	int hpfs_trim_fs(struct super_block , u64, u64, u64, unsigned );

	/* anode.c */

	secno hpfs_bplus_lookup(struct super_block , struct inode , struct bplus_header , unsigned, struct buffer_head );
	secno hpfs_add_sector_to_btree(struct super_block *, secno, int, unsigned);
	void hpfs_remove_btree(struct super_block , struct bplus_header );
	int hpfs_ea_read(struct super_block , secno, int, unsigned, unsigned, char );
	int hpfs_ea_write(struct super_block , secno, int, unsigned, unsigned, const char );
	void hpfs_ea_remove(struct super_block *, secno, int, unsigned);
	void hpfs_truncate_btree(struct super_block *, secno, int, unsigned);
	void hpfs_remove_fnode(struct super_block *, fnode_secno fno);

	/* buffer.c */

	secno hpfs_search_hotfix_map(struct super_block *s, secno sec);
	unsigned hpfs_search_hotfix_map_for_range(struct super_block *s, secno sec, unsigned n);
	void hpfs_prefetch_sectors(struct super_block *, unsigned, int);
	void hpfs_map_sector(struct super_block , unsigned, struct buffer_head **, int);
	void hpfs_get_sector(struct super_block , unsigned, struct buffer_head **);
	void hpfs_map_4sectors(struct super_block , unsigned, struct quad_buffer_head *, int);
	void hpfs_get_4sectors(struct super_block , unsigned, struct quad_buffer_head *);
	void hpfs_brelse4(struct quad_buffer_head *);
	void hpfs_mark_4buffers_dirty(struct quad_buffer_head *);

	/* dentry.c */

	extern const struct dentry_operations hpfs_dentry_operations;

	/* dir.c */

	struct dentry hpfs_lookup(struct inode , struct dentry *, unsigned int);
	extern const struct file_operations hpfs_dir_ops;

	/* dnode.c */

	int hpfs_add_pos(struct inode , loff_t );
	void hpfs_del_pos(struct inode , loff_t );
	struct hpfs_dirent hpfs_add_de(struct super_block , struct dnode *,
	const unsigned char *, unsigned, secno);
	int hpfs_add_dirent(struct inode , const unsigned char , unsigned,
	struct hpfs_dirent *);
	int hpfs_remove_dirent(struct inode , dnode_secno, struct hpfs_dirent , struct quad_buffer_head *, int);
	void hpfs_count_dnodes(struct super_block , dnode_secno, int , int , int );
	dnode_secno hpfs_de_as_down_as_possible(struct super_block *, dnode_secno dno);
	struct hpfs_dirent map_pos_dirent(struct inode , loff_t , struct quad_buffer_head );
	struct hpfs_dirent map_dirent(struct inode , dnode_secno,
	const unsigned char , unsigned, dnode_secno ,
	struct quad_buffer_head *);
	void hpfs_remove_dtree(struct super_block *, dnode_secno);
	struct hpfs_dirent map_fnode_dirent(struct super_block , fnode_secno, struct fnode , struct quad_buffer_head );

	/* ea.c */

	void hpfs_ea_ext_remove(struct super_block *, secno, int, unsigned);
	int hpfs_read_ea(struct super_block , struct fnode , char , char , int);
	char hpfs_get_ea(struct super_block , struct fnode , char , int *);
	void hpfs_set_ea(struct inode , struct fnode , const char *,
	const char *, int);

	/* file.c */

	int hpfs_file_fsync(struct file *, loff_t, loff_t, int);
	void hpfs_truncate(struct inode *);
	extern const struct file_operations hpfs_file_ops;
	extern const struct inode_operations hpfs_file_iops;
	extern const struct address_space_operations hpfs_aops;

	/* inode.c */

	void hpfs_init_inode(struct inode *);
	void hpfs_read_inode(struct inode *);
	void hpfs_write_inode(struct inode *);
	void hpfs_write_inode_nolock(struct inode *);
	int hpfs_setattr(struct user_namespace , struct dentry , struct iattr *);
	void hpfs_write_if_changed(struct inode *);
	void hpfs_evict_inode(struct inode *);

	/* map.c */

	__le32 hpfs_map_dnode_bitmap(struct super_block , struct quad_buffer_head *);
	__le32 hpfs_map_bitmap(struct super_block , unsigned, struct quad_buffer_head , char );
	void hpfs_prefetch_bitmap(struct super_block *, unsigned);
	unsigned char hpfs_load_code_page(struct super_block , secno);
	__le32 hpfs_load_bitmap_directory(struct super_block , secno bmp);
	void hpfs_load_hotfix_map(struct super_block s, struct hpfs_spare_block spareblock);
	struct fnode hpfs_map_fnode(struct super_block s, ino_t, struct buffer_head **);
	struct anode hpfs_map_anode(struct super_block s, anode_secno, struct buffer_head **);
	struct dnode hpfs_map_dnode(struct super_block s, dnode_secno, struct quad_buffer_head *);
	dnode_secno hpfs_fnode_dno(struct super_block *s, ino_t ino);

	/* name.c */

	unsigned char hpfs_upcase(unsigned char *, unsigned char);
	int hpfs_chk_name(const unsigned char , unsigned );
	unsigned char hpfs_translate_name(struct super_block , unsigned char *, unsigned, int, int);
	int hpfs_compare_names(struct super_block , const unsigned char , unsigned,
	const unsigned char *, unsigned, int);
	int hpfs_is_name_long(const unsigned char *, unsigned);
	void hpfs_adjust_length(const unsigned char , unsigned );

	/* namei.c */

	extern const struct inode_operations hpfs_dir_iops;
	extern const struct address_space_operations hpfs_symlink_aops;

	static inline struct hpfs_inode_info hpfs_i(struct inode inode)
	{
	return container_of(inode, struct hpfs_inode_info, vfs_inode);
	}

	static inline struct hpfs_sb_info hpfs_sb(struct super_block sb)
	{
	return sb->s_fs_info;
	}

	/* super.c */

	__printf(2, 3)
	void hpfs_error(struct super_block , const char , ...);
	int hpfs_stop_cycles(struct super_block , int, int , int , char );
	unsigned hpfs_get_free_dnodes(struct super_block *);
	long hpfs_ioctl(struct file *file, unsigned cmd, unsigned long arg);

	/*
	* local time (HPFS) to GMT (Unix)
	*/

	static inline time64_t local_to_gmt(struct super_block *s, time64_t t)
	{
	extern struct timezone sys_tz;
	return t + sys_tz.tz_minuteswest * 60 + hpfs_sb(s)->sb_timeshift;
	}

	static inline time32_t gmt_to_local(struct super_block *s, time64_t t)
	{
	extern struct timezone sys_tz;
	return t - sys_tz.tz_minuteswest * 60 - hpfs_sb(s)->sb_timeshift;
	}

	static inline time32_t local_get_seconds(struct super_block *s)
	{
	return gmt_to_local(s, ktime_get_real_seconds());
	}

	/*
	* Locking:
	*
	* hpfs_lock() locks the whole filesystem. It must be taken
	* on any method called by the VFS.
	*
	* We don't do any per-file locking anymore, it is hard to
	* review and HPFS is not performance-sensitive anyway.
	*/
	static inline void hpfs_lock(struct super_block *s)
	{
	struct hpfs_sb_info *sbi = hpfs_sb(s);
	mutex_lock(&sbi->hpfs_mutex);
	}

	static inline void hpfs_unlock(struct super_block *s)
	{
	struct hpfs_sb_info *sbi = hpfs_sb(s);
	mutex_unlock(&sbi->hpfs_mutex);
	}

	static inline void hpfs_lock_assert(struct super_block *s)
	{
	struct hpfs_sb_info *sbi = hpfs_sb(s);
	WARN_ON(!mutex_is_locked(&sbi->hpfs_mutex));
	}