1 /* SPDX-License-Identifier: GPL-2.0 */
39 	unsigned char errors;	   /* On error: continue, panic, remount-ro */
47 		 utf8:1,	   /* Use of UTF-8 character set (Default) */
64  * MS-DOS file system in-core superblock data
67 	unsigned short sec_per_clus;  /* sectors/cluster */
69 	unsigned int cluster_size;    /* cluster size */
76 	unsigned long max_cluster;    /* maximum cluster number */
77 	unsigned long root_cluster;   /* first cluster of the root directory */
82 	unsigned int prev_free;      /* previously allocated cluster number */
83 	unsigned int free_clusters;  /* -1 if undefined */
113  * MS-DOS file system inode data in memory
122 	/* NOTE: mmu_private is 64bits, so must hold ->i_mutex to access */
125 	int i_start;		/* first cluster or 0 */
126 	int i_logstart;		/* logical first cluster */
128 	loff_t i_pos;		/* on-disk position of directory entry or 0 */
137 	loff_t i_pos;		/* on-disk position of directory entry */
146 	return sb->s_fs_info;  in MSDOS_SB()
155 	return sbi->fat_bits == 12;  in is_fat12()
160 	return sbi->fat_bits == 16;  in is_fat16()
165 	return sbi->fat_bits == 32;  in is_fat32()
183  * If ->i_mode can't hold S_IWUGO (i.e. ATTR_RO), we use ->i_attrs to
184  * save ATTR_RO instead of ->i_mode.
186  * If it's directory and !sbi->options.rodir, ATTR_RO isn't read-only
191 	struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb);  in fat_mode_can_hold_ro()
194 	if (S_ISDIR(inode->i_mode)) {  in fat_mode_can_hold_ro()
195 		if (!sbi->options.rodir)  in fat_mode_can_hold_ro()
197 		mask = ~sbi->options.fs_dmask;  in fat_mode_can_hold_ro()
199 		mask = ~sbi->options.fs_fmask;  in fat_mode_can_hold_ro()
206 /* Convert attribute bits and a mask to the UNIX mode. */
208 				   u8 attrs, umode_t mode)  in fat_make_mode()  argument
210 	if (attrs & ATTR_RO && !((attrs & ATTR_DIR) && !sbi->options.rodir))  in fat_make_mode()
211 		mode &= ~S_IWUGO;  in fat_make_mode()
214 		return (mode & ~sbi->options.fs_dmask) | S_IFDIR;  in fat_make_mode()
216 		return (mode & ~sbi->options.fs_fmask) | S_IFREG;  in fat_make_mode()
222 	u8 attrs = MSDOS_I(inode)->i_attrs;  in fat_make_attrs()
223 	if (S_ISDIR(inode->i_mode))  in fat_make_attrs()
225 	if (fat_mode_can_hold_ro(inode) && !(inode->i_mode & S_IWUGO))  in fat_make_attrs()
233 		MSDOS_I(inode)->i_attrs = attrs & ATTR_UNUSED;  in fat_save_attrs()
235 		MSDOS_I(inode)->i_attrs = attrs & (ATTR_UNUSED | ATTR_RO);  in fat_save_attrs()
251 	return ((sector_t)clus - FAT_START_ENT) * sbi->sec_per_clus  in fat_clus_to_blknr()
252 		+ sbi->data_start;  in fat_clus_to_blknr()
258 	*blknr = i_pos >> sbi->dir_per_block_bits;  in fat_get_blknr_offset()
259 	*offset = i_pos & (sbi->dir_per_block - 1);  in fat_get_blknr_offset()
267 	spin_lock(&sbi->inode_hash_lock);  in fat_i_pos_read()
269 	i_pos = MSDOS_I(inode)->i_pos;  in fat_i_pos_read()
271 	spin_unlock(&sbi->inode_hash_lock);  in fat_i_pos_read()
279 	while (len--) {  in fat16_towchar()
291 	int cluster = le16_to_cpu(de->start);  in fat_get_start()  local
293 		cluster |= (le16_to_cpu(de->starthi) << 16);  in fat_get_start()
294 	return cluster;  in fat_get_start()
297 static inline void fat_set_start(struct msdos_dir_entry *de, int cluster)  in fat_set_start()  argument
299 	de->start   = cpu_to_le16(cluster);  in fat_set_start()
300 	de->starthi = cpu_to_le16(cluster >> 16);  in fat_set_start()
306 	while (len--) {  in fatwchar_to16()
319 extern int fat_get_cluster(struct inode *inode, int cluster,
359 	fatent->nr_bhs = 0;  in fatent_init()
360 	fatent->entry = 0;  in fatent_init()
361 	fatent->u.ent32_p = NULL;  in fatent_init()
362 	fatent->bhs[0] = fatent->bhs[1] = NULL;  in fatent_init()
363 	fatent->fat_inode = NULL;  in fatent_init()
368 	fatent->entry = entry;  in fatent_set_entry()
369 	fatent->u.ent32_p = NULL;  in fatent_set_entry()
375 	fatent->u.ent32_p = NULL;  in fatent_brelse()
376 	for (i = 0; i < fatent->nr_bhs; i++)  in fatent_brelse()
377 		brelse(fatent->bhs[i]);  in fatent_brelse()
378 	fatent->nr_bhs = 0;  in fatent_brelse()
379 	fatent->bhs[0] = fatent->bhs[1] = NULL;  in fatent_brelse()
380 	fatent->fat_inode = NULL;  in fatent_brelse()
385 	return FAT_START_ENT <= entry && entry < sbi->max_cluster;  in fat_valid_entry()
393 extern int fat_alloc_clusters(struct inode *inode, int *cluster,
395 extern int fat_free_clusters(struct inode *inode, int cluster);
448 	__fat_fs_error(sb, __ratelimit(&MSDOS_SB(sb)->ratelimit), fmt , ## args)
450 #define FAT_PRINTK_PREFIX "%sFAT-fs (%s): "
460 			if (__ratelimit(&MSDOS_SB(sb)->ratelimit))	\