21 static void fat12_ent_blocknr(struct super_block *sb, int entry,  in fat12_ent_blocknr()  argument
24 	struct msdos_sb_info *sbi = MSDOS_SB(sb);  in fat12_ent_blocknr()
27 	*offset = bytes & (sb->s_blocksize - 1);  in fat12_ent_blocknr()
28 	*blocknr = sbi->fat_start + (bytes >> sb->s_blocksize_bits);  in fat12_ent_blocknr()
31 static void fat_ent_blocknr(struct super_block *sb, int entry,  in fat_ent_blocknr()  argument
34 	struct msdos_sb_info *sbi = MSDOS_SB(sb);  in fat_ent_blocknr()
37 	*offset = bytes & (sb->s_blocksize - 1);  in fat_ent_blocknr()
38 	*blocknr = sbi->fat_start + (bytes >> sb->s_blocksize_bits);  in fat_ent_blocknr()
67 static int fat12_ent_bread(struct super_block *sb, struct fat_entry *fatent,  in fat12_ent_bread()  argument
72 	WARN_ON(blocknr < MSDOS_SB(sb)->fat_start);  in fat12_ent_bread()
73 	fatent->fat_inode = MSDOS_SB(sb)->fat_inode;  in fat12_ent_bread()
75 	bhs[0] = sb_bread(sb, blocknr);  in fat12_ent_bread()
79 	if ((offset + 1) < sb->s_blocksize)  in fat12_ent_bread()
84 		bhs[1] = sb_bread(sb, blocknr);  in fat12_ent_bread()
95 	fat_msg(sb, KERN_ERR, "FAT read failed (blocknr %llu)", (llu)blocknr);  in fat12_ent_bread()
99 static int fat_ent_bread(struct super_block *sb, struct fat_entry *fatent,  in fat_ent_bread()  argument
102 	struct fatent_operations *ops = MSDOS_SB(sb)->fatent_ops;  in fat_ent_bread()
104 	WARN_ON(blocknr < MSDOS_SB(sb)->fat_start);  in fat_ent_bread()
105 	fatent->fat_inode = MSDOS_SB(sb)->fat_inode;  in fat_ent_bread()
106 	fatent->bhs[0] = sb_bread(sb, blocknr);  in fat_ent_bread()
108 		fat_msg(sb, KERN_ERR, "FAT read failed (blocknr %llu)",  in fat_ent_bread()
286 void fat_ent_access_init(struct super_block *sb)  in fat_ent_access_init()  argument
288 	struct msdos_sb_info *sbi = MSDOS_SB(sb);  in fat_ent_access_init()
308 static void mark_fsinfo_dirty(struct super_block *sb)  in mark_fsinfo_dirty()  argument
310 	struct msdos_sb_info *sbi = MSDOS_SB(sb);  in mark_fsinfo_dirty()
312 	if (sb->s_flags & MS_RDONLY || sbi->fat_bits != 32)  in mark_fsinfo_dirty()
318 static inline int fat_ent_update_ptr(struct super_block *sb,  in fat_ent_update_ptr()  argument
322 	struct msdos_sb_info *sbi = MSDOS_SB(sb);  in fat_ent_update_ptr()
330 		if ((offset + 1) < sb->s_blocksize) {  in fat_ent_update_ptr()
350 	struct super_block *sb = inode->i_sb;  in fat_ent_read()  local
358 		fat_fs_error(sb, "invalid access to FAT (entry 0x%08x)", entry);  in fat_ent_read()
363 	ops->ent_blocknr(sb, entry, &offset, &blocknr);  in fat_ent_read()
365 	if (!fat_ent_update_ptr(sb, fatent, offset, blocknr)) {  in fat_ent_read()
367 		err = ops->ent_bread(sb, fatent, offset, blocknr);  in fat_ent_read()
375 static int fat_mirror_bhs(struct super_block *sb, struct buffer_head **bhs,  in fat_mirror_bhs()  argument
378 	struct msdos_sb_info *sbi = MSDOS_SB(sb);  in fat_mirror_bhs()
387 			c_bh = sb_getblk(sb, backup_fat + bhs[n]->b_blocknr);  in fat_mirror_bhs()
392 			memcpy(c_bh->b_data, bhs[n]->b_data, sb->s_blocksize);  in fat_mirror_bhs()
395 			if (sb->s_flags & MS_SYNCHRONOUS)  in fat_mirror_bhs()
409 	struct super_block *sb = inode->i_sb;  in fat_ent_write()  local
410 	struct fatent_operations *ops = MSDOS_SB(sb)->fatent_ops;  in fat_ent_write()
419 	return fat_mirror_bhs(sb, fatent->bhs, fatent->nr_bhs);  in fat_ent_write()
432 static inline int fat_ent_read_block(struct super_block *sb,  in fat_ent_read_block()  argument
435 	struct fatent_operations *ops = MSDOS_SB(sb)->fatent_ops;  in fat_ent_read_block()
440 	ops->ent_blocknr(sb, fatent->entry, &offset, &blocknr);  in fat_ent_read_block()
441 	return ops->ent_bread(sb, fatent, offset, blocknr);  in fat_ent_read_block()
464 	struct super_block *sb = inode->i_sb;  in fat_alloc_clusters()  local
465 	struct msdos_sb_info *sbi = MSDOS_SB(sb);  in fat_alloc_clusters()
489 		err = fat_ent_read_block(sb, &fatent);  in fat_alloc_clusters()
533 	mark_fsinfo_dirty(sb);  in fat_alloc_clusters()
539 			err = fat_mirror_bhs(sb, bhs, nr_bhs);  in fat_alloc_clusters()
552 	struct super_block *sb = inode->i_sb;  in fat_free_clusters()  local
553 	struct msdos_sb_info *sbi = MSDOS_SB(sb);  in fat_free_clusters()
569 			fat_fs_error(sb, "%s: deleting FAT entry beyond EOF",  in fat_free_clusters()
584 				sb_issue_discard(sb,  in fat_free_clusters()
600 			if (sb->s_flags & MS_SYNCHRONOUS) {  in fat_free_clusters()
605 			err = fat_mirror_bhs(sb, bhs, nr_bhs);  in fat_free_clusters()
615 	if (sb->s_flags & MS_SYNCHRONOUS) {  in fat_free_clusters()
620 	err = fat_mirror_bhs(sb, bhs, nr_bhs);  in fat_free_clusters()
627 		mark_fsinfo_dirty(sb);  in fat_free_clusters()
636 static void fat_ent_reada(struct super_block *sb, struct fat_entry *fatent,  in fat_ent_reada()  argument
639 	struct fatent_operations *ops = MSDOS_SB(sb)->fatent_ops;  in fat_ent_reada()
643 	ops->ent_blocknr(sb, fatent->entry, &offset, &blocknr);  in fat_ent_reada()
646 		sb_breadahead(sb, blocknr + i);  in fat_ent_reada()
649 int fat_count_free_clusters(struct super_block *sb)  in fat_count_free_clusters()  argument
651 	struct msdos_sb_info *sbi = MSDOS_SB(sb);  in fat_count_free_clusters()
661 	reada_blocks = FAT_READA_SIZE >> sb->s_blocksize_bits;  in fat_count_free_clusters()
672 			fat_ent_reada(sb, &fatent, min(reada_blocks, rest));  in fat_count_free_clusters()
676 		err = fat_ent_read_block(sb, &fatent);  in fat_count_free_clusters()
687 	mark_fsinfo_dirty(sb);  in fat_count_free_clusters()