41 static void fat12_ent_set_ptr(struct fat_entry *fatent, int offset)  in fat12_ent_set_ptr()  argument
43 	struct buffer_head **bhs = fatent->bhs;  in fat12_ent_set_ptr()
44 	if (fatent->nr_bhs == 1) {  in fat12_ent_set_ptr()
46 		fatent->u.ent12_p[0] = bhs[0]->b_data + offset;  in fat12_ent_set_ptr()
47 		fatent->u.ent12_p[1] = bhs[0]->b_data + (offset + 1);  in fat12_ent_set_ptr()
50 		fatent->u.ent12_p[0] = bhs[0]->b_data + offset;  in fat12_ent_set_ptr()
51 		fatent->u.ent12_p[1] = bhs[1]->b_data;  in fat12_ent_set_ptr()
55 static void fat16_ent_set_ptr(struct fat_entry *fatent, int offset)  in fat16_ent_set_ptr()  argument
58 	fatent->u.ent16_p = (__le16 *)(fatent->bhs[0]->b_data + offset);  in fat16_ent_set_ptr()
61 static void fat32_ent_set_ptr(struct fat_entry *fatent, int offset)  in fat32_ent_set_ptr()  argument
64 	fatent->u.ent32_p = (__le32 *)(fatent->bhs[0]->b_data + offset);  in fat32_ent_set_ptr()
67 static int fat12_ent_bread(struct super_block *sb, struct fat_entry *fatent,  in fat12_ent_bread()  argument
70 	struct buffer_head **bhs = fatent->bhs;  in fat12_ent_bread()
73 	fatent->fat_inode = MSDOS_SB(sb)->fat_inode;  in fat12_ent_bread()
80 		fatent->nr_bhs = 1;  in fat12_ent_bread()
87 		fatent->nr_bhs = 2;  in fat12_ent_bread()
89 	fat12_ent_set_ptr(fatent, offset);  in fat12_ent_bread()
99 static int fat_ent_bread(struct super_block *sb, struct fat_entry *fatent,  in fat_ent_bread()  argument
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()
107 	if (!fatent->bhs[0]) {  in fat_ent_bread()
112 	fatent->nr_bhs = 1;  in fat_ent_bread()
113 	ops->ent_set_ptr(fatent, offset);  in fat_ent_bread()
117 static int fat12_ent_get(struct fat_entry *fatent)  in fat12_ent_get()  argument
119 	u8 **ent12_p = fatent->u.ent12_p;  in fat12_ent_get()
123 	if (fatent->entry & 1)  in fat12_ent_get()
135 static int fat16_ent_get(struct fat_entry *fatent)  in fat16_ent_get()  argument
137 	int next = le16_to_cpu(*fatent->u.ent16_p);  in fat16_ent_get()
138 	WARN_ON((unsigned long)fatent->u.ent16_p & (2 - 1));  in fat16_ent_get()
144 static int fat32_ent_get(struct fat_entry *fatent)  in fat32_ent_get()  argument
146 	int next = le32_to_cpu(*fatent->u.ent32_p) & 0x0fffffff;  in fat32_ent_get()
147 	WARN_ON((unsigned long)fatent->u.ent32_p & (4 - 1));  in fat32_ent_get()
153 static void fat12_ent_put(struct fat_entry *fatent, int new)  in fat12_ent_put()  argument
155 	u8 **ent12_p = fatent->u.ent12_p;  in fat12_ent_put()
161 	if (fatent->entry & 1) {  in fat12_ent_put()
170 	mark_buffer_dirty_inode(fatent->bhs[0], fatent->fat_inode);  in fat12_ent_put()
171 	if (fatent->nr_bhs == 2)  in fat12_ent_put()
172 		mark_buffer_dirty_inode(fatent->bhs[1], fatent->fat_inode);  in fat12_ent_put()
175 static void fat16_ent_put(struct fat_entry *fatent, int new)  in fat16_ent_put()  argument
180 	*fatent->u.ent16_p = cpu_to_le16(new);  in fat16_ent_put()
181 	mark_buffer_dirty_inode(fatent->bhs[0], fatent->fat_inode);  in fat16_ent_put()
184 static void fat32_ent_put(struct fat_entry *fatent, int new)  in fat32_ent_put()  argument
187 	new |= le32_to_cpu(*fatent->u.ent32_p) & ~0x0fffffff;  in fat32_ent_put()
188 	*fatent->u.ent32_p = cpu_to_le32(new);  in fat32_ent_put()
189 	mark_buffer_dirty_inode(fatent->bhs[0], fatent->fat_inode);  in fat32_ent_put()
192 static int fat12_ent_next(struct fat_entry *fatent)  in fat12_ent_next()  argument
194 	u8 **ent12_p = fatent->u.ent12_p;  in fat12_ent_next()
195 	struct buffer_head **bhs = fatent->bhs;  in fat12_ent_next()
196 	u8 *nextp = ent12_p[1] + 1 + (fatent->entry & 1);  in fat12_ent_next()
198 	fatent->entry++;  in fat12_ent_next()
199 	if (fatent->nr_bhs == 1) {  in fat12_ent_next()
217 		fatent->nr_bhs = 1;  in fat12_ent_next()
225 static int fat16_ent_next(struct fat_entry *fatent)  in fat16_ent_next()  argument
227 	const struct buffer_head *bh = fatent->bhs[0];  in fat16_ent_next()
228 	fatent->entry++;  in fat16_ent_next()
229 	if (fatent->u.ent16_p < (__le16 *)(bh->b_data + (bh->b_size - 2))) {  in fat16_ent_next()
230 		fatent->u.ent16_p++;  in fat16_ent_next()
233 	fatent->u.ent16_p = NULL;  in fat16_ent_next()
237 static int fat32_ent_next(struct fat_entry *fatent)  in fat32_ent_next()  argument
239 	const struct buffer_head *bh = fatent->bhs[0];  in fat32_ent_next()
240 	fatent->entry++;  in fat32_ent_next()
241 	if (fatent->u.ent32_p < (__le32 *)(bh->b_data + (bh->b_size - 4))) {  in fat32_ent_next()
242 		fatent->u.ent32_p++;  in fat32_ent_next()
245 	fatent->u.ent32_p = NULL;  in fat32_ent_next()
319 				     struct fat_entry *fatent,  in fat_ent_update_ptr()  argument
324 	struct buffer_head **bhs = fatent->bhs;  in fat_ent_update_ptr()
327 	if (!fatent->nr_bhs || bhs[0]->b_blocknr != blocknr)  in fat_ent_update_ptr()
332 			if (fatent->nr_bhs == 2) {  in fat_ent_update_ptr()
334 				fatent->nr_bhs = 1;  in fat_ent_update_ptr()
338 			if (fatent->nr_bhs != 2)  in fat_ent_update_ptr()
344 	ops->ent_set_ptr(fatent, offset);  in fat_ent_update_ptr()
348 int fat_ent_read(struct inode *inode, struct fat_entry *fatent, int entry)  in fat_ent_read()  argument
357 		fatent_brelse(fatent);  in fat_ent_read()
362 	fatent_set_entry(fatent, entry);  in fat_ent_read()
365 	if (!fat_ent_update_ptr(sb, fatent, offset, blocknr)) {  in fat_ent_read()
366 		fatent_brelse(fatent);  in fat_ent_read()
367 		err = ops->ent_bread(sb, fatent, offset, blocknr);  in fat_ent_read()
371 	return ops->ent_get(fatent);  in fat_ent_read()
406 int fat_ent_write(struct inode *inode, struct fat_entry *fatent,  in fat_ent_write()  argument
413 	ops->ent_put(fatent, new);  in fat_ent_write()
415 		err = fat_sync_bhs(fatent->bhs, fatent->nr_bhs);  in fat_ent_write()
419 	return fat_mirror_bhs(sb, fatent->bhs, fatent->nr_bhs);  in fat_ent_write()
423 			       struct fat_entry *fatent)  in fat_ent_next()  argument
425 	if (sbi->fatent_ops->ent_next(fatent)) {  in fat_ent_next()
426 		if (fatent->entry < sbi->max_cluster)  in fat_ent_next()
433 				     struct fat_entry *fatent)  in fat_ent_read_block()  argument
439 	fatent_brelse(fatent);  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()
445 			    struct fat_entry *fatent)  in fat_collect_bhs()  argument
449 	for (n = 0; n < fatent->nr_bhs; n++) {  in fat_collect_bhs()
451 			if (fatent->bhs[n] == bhs[i])  in fat_collect_bhs()
455 			get_bh(fatent->bhs[n]);  in fat_collect_bhs()
456 			bhs[i] = fatent->bhs[n];  in fat_collect_bhs()
467 	struct fat_entry fatent, prev_ent;  in fat_alloc_clusters()  local
483 	fatent_init(&fatent);  in fat_alloc_clusters()
484 	fatent_set_entry(&fatent, sbi->prev_free + 1);  in fat_alloc_clusters()
486 		if (fatent.entry >= sbi->max_cluster)  in fat_alloc_clusters()
487 			fatent.entry = FAT_START_ENT;  in fat_alloc_clusters()
488 		fatent_set_entry(&fatent, fatent.entry);  in fat_alloc_clusters()
489 		err = fat_ent_read_block(sb, &fatent);  in fat_alloc_clusters()
495 			if (ops->ent_get(&fatent) == FAT_ENT_FREE) {  in fat_alloc_clusters()
496 				int entry = fatent.entry;  in fat_alloc_clusters()
499 				ops->ent_put(&fatent, FAT_ENT_EOF);  in fat_alloc_clusters()
503 				fat_collect_bhs(bhs, &nr_bhs, &fatent);  in fat_alloc_clusters()
518 				prev_ent = fatent;  in fat_alloc_clusters()
523 		} while (fat_ent_next(sbi, &fatent));  in fat_alloc_clusters()
534 	fatent_brelse(&fatent);  in fat_alloc_clusters()
555 	struct fat_entry fatent;  in fat_free_clusters()  local
561 	fatent_init(&fatent);  in fat_free_clusters()
564 		cluster = fat_ent_read(inode, &fatent, cluster);  in fat_free_clusters()
581 			if (cluster != fatent.entry + 1) {  in fat_free_clusters()
582 				int nr_clus = fatent.entry - first_cl + 1;  in fat_free_clusters()
593 		ops->ent_put(&fatent, FAT_ENT_FREE);  in fat_free_clusters()
599 		if (nr_bhs + fatent.nr_bhs > MAX_BUF_PER_PAGE) {  in fat_free_clusters()
612 		fat_collect_bhs(bhs, &nr_bhs, &fatent);  in fat_free_clusters()
622 	fatent_brelse(&fatent);  in fat_free_clusters()
636 static void fat_ent_reada(struct super_block *sb, struct fat_entry *fatent,  in fat_ent_reada()  argument
643 	ops->ent_blocknr(sb, fatent->entry, &offset, &blocknr);  in fat_ent_reada()
653 	struct fat_entry fatent;  in fat_count_free_clusters()  local
666 	fatent_init(&fatent);  in fat_count_free_clusters()
667 	fatent_set_entry(&fatent, FAT_START_ENT);  in fat_count_free_clusters()
668 	while (fatent.entry < sbi->max_cluster) {  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()
681 			if (ops->ent_get(&fatent) == FAT_ENT_FREE)  in fat_count_free_clusters()
683 		} while (fat_ent_next(sbi, &fatent));  in fat_count_free_clusters()
688 	fatent_brelse(&fatent);  in fat_count_free_clusters()