43 static void fat12_ent_set_ptr(struct fat_entry *fatent, int offset)  in fat12_ent_set_ptr()  argument
45 	struct buffer_head **bhs = fatent->bhs;  in fat12_ent_set_ptr()
46 	if (fatent->nr_bhs == 1) {  in fat12_ent_set_ptr()
48 		fatent->u.ent12_p[0] = bhs[0]->b_data + offset;  in fat12_ent_set_ptr()
49 		fatent->u.ent12_p[1] = bhs[0]->b_data + (offset + 1);  in fat12_ent_set_ptr()
52 		fatent->u.ent12_p[0] = bhs[0]->b_data + offset;  in fat12_ent_set_ptr()
53 		fatent->u.ent12_p[1] = bhs[1]->b_data;  in fat12_ent_set_ptr()
57 static void fat16_ent_set_ptr(struct fat_entry *fatent, int offset)  in fat16_ent_set_ptr()  argument
60 	fatent->u.ent16_p = (__le16 *)(fatent->bhs[0]->b_data + offset);  in fat16_ent_set_ptr()
63 static void fat32_ent_set_ptr(struct fat_entry *fatent, int offset)  in fat32_ent_set_ptr()  argument
66 	fatent->u.ent32_p = (__le32 *)(fatent->bhs[0]->b_data + offset);  in fat32_ent_set_ptr()
69 static int fat12_ent_bread(struct super_block *sb, struct fat_entry *fatent,  in fat12_ent_bread()  argument
72 	struct buffer_head **bhs = fatent->bhs;  in fat12_ent_bread()
75 	fatent->fat_inode = MSDOS_SB(sb)->fat_inode;  in fat12_ent_bread()
82 		fatent->nr_bhs = 1;  in fat12_ent_bread()
89 		fatent->nr_bhs = 2;  in fat12_ent_bread()
91 	fat12_ent_set_ptr(fatent, offset);  in fat12_ent_bread()
102 static int fat_ent_bread(struct super_block *sb, struct fat_entry *fatent,  in fat_ent_bread()  argument
108 	fatent->fat_inode = MSDOS_SB(sb)->fat_inode;  in fat_ent_bread()
109 	fatent->bhs[0] = sb_bread(sb, blocknr);  in fat_ent_bread()
110 	if (!fatent->bhs[0]) {  in fat_ent_bread()
115 	fatent->nr_bhs = 1;  in fat_ent_bread()
116 	ops->ent_set_ptr(fatent, offset);  in fat_ent_bread()
120 static int fat12_ent_get(struct fat_entry *fatent)  in fat12_ent_get()  argument
122 	u8 **ent12_p = fatent->u.ent12_p;  in fat12_ent_get()
126 	if (fatent->entry & 1)  in fat12_ent_get()
138 static int fat16_ent_get(struct fat_entry *fatent)  in fat16_ent_get()  argument
140 	int next = le16_to_cpu(*fatent->u.ent16_p);  in fat16_ent_get()
141 	WARN_ON((unsigned long)fatent->u.ent16_p & (2 - 1));  in fat16_ent_get()
147 static int fat32_ent_get(struct fat_entry *fatent)  in fat32_ent_get()  argument
149 	int next = le32_to_cpu(*fatent->u.ent32_p) & 0x0fffffff;  in fat32_ent_get()
150 	WARN_ON((unsigned long)fatent->u.ent32_p & (4 - 1));  in fat32_ent_get()
156 static void fat12_ent_put(struct fat_entry *fatent, int new)  in fat12_ent_put()  argument
158 	u8 **ent12_p = fatent->u.ent12_p;  in fat12_ent_put()
164 	if (fatent->entry & 1) {  in fat12_ent_put()
173 	mark_buffer_dirty_inode(fatent->bhs[0], fatent->fat_inode);  in fat12_ent_put()
174 	if (fatent->nr_bhs == 2)  in fat12_ent_put()
175 		mark_buffer_dirty_inode(fatent->bhs[1], fatent->fat_inode);  in fat12_ent_put()
178 static void fat16_ent_put(struct fat_entry *fatent, int new)  in fat16_ent_put()  argument
183 	*fatent->u.ent16_p = cpu_to_le16(new);  in fat16_ent_put()
184 	mark_buffer_dirty_inode(fatent->bhs[0], fatent->fat_inode);  in fat16_ent_put()
187 static void fat32_ent_put(struct fat_entry *fatent, int new)  in fat32_ent_put()  argument
190 	new |= le32_to_cpu(*fatent->u.ent32_p) & ~0x0fffffff;  in fat32_ent_put()
191 	*fatent->u.ent32_p = cpu_to_le32(new);  in fat32_ent_put()
192 	mark_buffer_dirty_inode(fatent->bhs[0], fatent->fat_inode);  in fat32_ent_put()
195 static int fat12_ent_next(struct fat_entry *fatent)  in fat12_ent_next()  argument
197 	u8 **ent12_p = fatent->u.ent12_p;  in fat12_ent_next()
198 	struct buffer_head **bhs = fatent->bhs;  in fat12_ent_next()
199 	u8 *nextp = ent12_p[1] + 1 + (fatent->entry & 1);  in fat12_ent_next()
201 	fatent->entry++;  in fat12_ent_next()
202 	if (fatent->nr_bhs == 1) {  in fat12_ent_next()
220 		fatent->nr_bhs = 1;  in fat12_ent_next()
228 static int fat16_ent_next(struct fat_entry *fatent)  in fat16_ent_next()  argument
230 	const struct buffer_head *bh = fatent->bhs[0];  in fat16_ent_next()
231 	fatent->entry++;  in fat16_ent_next()
232 	if (fatent->u.ent16_p < (__le16 *)(bh->b_data + (bh->b_size - 2))) {  in fat16_ent_next()
233 		fatent->u.ent16_p++;  in fat16_ent_next()
236 	fatent->u.ent16_p = NULL;  in fat16_ent_next()
240 static int fat32_ent_next(struct fat_entry *fatent)  in fat32_ent_next()  argument
242 	const struct buffer_head *bh = fatent->bhs[0];  in fat32_ent_next()
243 	fatent->entry++;  in fat32_ent_next()
244 	if (fatent->u.ent32_p < (__le32 *)(bh->b_data + (bh->b_size - 4))) {  in fat32_ent_next()
245 		fatent->u.ent32_p++;  in fat32_ent_next()
248 	fatent->u.ent32_p = NULL;  in fat32_ent_next()
320 				     struct fat_entry *fatent,  in fat_ent_update_ptr()  argument
325 	struct buffer_head **bhs = fatent->bhs;  in fat_ent_update_ptr()
328 	if (!fatent->nr_bhs || bhs[0]->b_blocknr != blocknr)  in fat_ent_update_ptr()
333 			if (fatent->nr_bhs == 2) {  in fat_ent_update_ptr()
335 				fatent->nr_bhs = 1;  in fat_ent_update_ptr()
339 			if (fatent->nr_bhs != 2)  in fat_ent_update_ptr()
345 	ops->ent_set_ptr(fatent, offset);  in fat_ent_update_ptr()
349 int fat_ent_read(struct inode *inode, struct fat_entry *fatent, int entry)  in fat_ent_read()  argument
358 		fatent_brelse(fatent);  in fat_ent_read()
363 	fatent_set_entry(fatent, entry);  in fat_ent_read()
366 	if (!fat_ent_update_ptr(sb, fatent, offset, blocknr)) {  in fat_ent_read()
367 		fatent_brelse(fatent);  in fat_ent_read()
368 		err = ops->ent_bread(sb, fatent, offset, blocknr);  in fat_ent_read()
372 	return ops->ent_get(fatent);  in fat_ent_read()
410 int fat_ent_write(struct inode *inode, struct fat_entry *fatent,  in fat_ent_write()  argument
417 	ops->ent_put(fatent, new);  in fat_ent_write()
419 		err = fat_sync_bhs(fatent->bhs, fatent->nr_bhs);  in fat_ent_write()
423 	return fat_mirror_bhs(sb, fatent->bhs, fatent->nr_bhs);  in fat_ent_write()
427 			       struct fat_entry *fatent)  in fat_ent_next()  argument
429 	if (sbi->fatent_ops->ent_next(fatent)) {  in fat_ent_next()
430 		if (fatent->entry < sbi->max_cluster)  in fat_ent_next()
437 				     struct fat_entry *fatent)  in fat_ent_read_block()  argument
443 	fatent_brelse(fatent);  in fat_ent_read_block()
444 	ops->ent_blocknr(sb, fatent->entry, &offset, &blocknr);  in fat_ent_read_block()
445 	return ops->ent_bread(sb, fatent, offset, blocknr);  in fat_ent_read_block()
449 			    struct fat_entry *fatent)  in fat_collect_bhs()  argument
453 	for (n = 0; n < fatent->nr_bhs; n++) {  in fat_collect_bhs()
455 			if (fatent->bhs[n] == bhs[i])  in fat_collect_bhs()
459 			get_bh(fatent->bhs[n]);  in fat_collect_bhs()
460 			bhs[i] = fatent->bhs[n];  in fat_collect_bhs()
471 	struct fat_entry fatent, prev_ent;  in fat_alloc_clusters()  local
487 	fatent_init(&fatent);  in fat_alloc_clusters()
488 	fatent_set_entry(&fatent, sbi->prev_free + 1);  in fat_alloc_clusters()
490 		if (fatent.entry >= sbi->max_cluster)  in fat_alloc_clusters()
491 			fatent.entry = FAT_START_ENT;  in fat_alloc_clusters()
492 		fatent_set_entry(&fatent, fatent.entry);  in fat_alloc_clusters()
493 		err = fat_ent_read_block(sb, &fatent);  in fat_alloc_clusters()
499 			if (ops->ent_get(&fatent) == FAT_ENT_FREE) {  in fat_alloc_clusters()
500 				int entry = fatent.entry;  in fat_alloc_clusters()
503 				ops->ent_put(&fatent, FAT_ENT_EOF);  in fat_alloc_clusters()
507 				fat_collect_bhs(bhs, &nr_bhs, &fatent);  in fat_alloc_clusters()
522 				prev_ent = fatent;  in fat_alloc_clusters()
527 		} while (fat_ent_next(sbi, &fatent));  in fat_alloc_clusters()
538 	fatent_brelse(&fatent);  in fat_alloc_clusters()
559 	struct fat_entry fatent;  in fat_free_clusters()  local
565 	fatent_init(&fatent);  in fat_free_clusters()
568 		cluster = fat_ent_read(inode, &fatent, cluster);  in fat_free_clusters()
585 			if (cluster != fatent.entry + 1) {  in fat_free_clusters()
586 				int nr_clus = fatent.entry - first_cl + 1;  in fat_free_clusters()
597 		ops->ent_put(&fatent, FAT_ENT_FREE);  in fat_free_clusters()
603 		if (nr_bhs + fatent.nr_bhs > MAX_BUF_PER_PAGE) {  in fat_free_clusters()
616 		fat_collect_bhs(bhs, &nr_bhs, &fatent);  in fat_free_clusters()
626 	fatent_brelse(&fatent);  in fat_free_clusters()
648 			struct fat_entry *fatent, int ent_limit)  in fat_ra_init()  argument
662 	if (fatent->entry >= ent_limit)  in fat_ra_init()
670 	ops->ent_blocknr(sb, fatent->entry, &offset, &blocknr);  in fat_ra_init()
684 			  struct fat_entry *fatent)  in fat_ent_reada()  argument
696 		ops->ent_blocknr(sb, fatent->entry, &offset, &blocknr);  in fat_ent_reada()
720 	struct fat_entry fatent;  in fat_count_free_clusters()  local
729 	fatent_init(&fatent);  in fat_count_free_clusters()
730 	fatent_set_entry(&fatent, FAT_START_ENT);  in fat_count_free_clusters()
731 	fat_ra_init(sb, &fatent_ra, &fatent, sbi->max_cluster);  in fat_count_free_clusters()
732 	while (fatent.entry < sbi->max_cluster) {  in fat_count_free_clusters()
734 		fat_ent_reada(sb, &fatent_ra, &fatent);  in fat_count_free_clusters()
736 		err = fat_ent_read_block(sb, &fatent);  in fat_count_free_clusters()
741 			if (ops->ent_get(&fatent) == FAT_ENT_FREE)  in fat_count_free_clusters()
743 		} while (fat_ent_next(sbi, &fatent));  in fat_count_free_clusters()
749 	fatent_brelse(&fatent);  in fat_count_free_clusters()
767 	struct fat_entry fatent;  in fat_trim_fs()  local
788 	fatent_init(&fatent);  in fat_trim_fs()
790 	fatent_set_entry(&fatent, ent_start);  in fat_trim_fs()
791 	fat_ra_init(sb, &fatent_ra, &fatent, ent_end + 1);  in fat_trim_fs()
792 	while (fatent.entry <= ent_end) {  in fat_trim_fs()
794 		fat_ent_reada(sb, &fatent_ra, &fatent);  in fat_trim_fs()
796 		err = fat_ent_read_block(sb, &fatent);  in fat_trim_fs()
800 			if (ops->ent_get(&fatent) == FAT_ENT_FREE) {  in fat_trim_fs()
804 					u32 clus = fatent.entry - free;  in fat_trim_fs()
815 		} while (fat_ent_next(sbi, &fatent) && fatent.entry <= ent_end);  in fat_trim_fs()
823 			fatent_brelse(&fatent);  in fat_trim_fs()
831 		u32 clus = fatent.entry - free;  in fat_trim_fs()
842 	fatent_brelse(&fatent);  in fat_trim_fs()