42 static void fat12_ent_set_ptr(struct fat_entry *fatent, int offset)  in fat12_ent_set_ptr()  argument
44 	struct buffer_head **bhs = fatent->bhs;  in fat12_ent_set_ptr()
45 	if (fatent->nr_bhs == 1) {  in fat12_ent_set_ptr()
47 		fatent->u.ent12_p[0] = bhs[0]->b_data + offset;  in fat12_ent_set_ptr()
48 		fatent->u.ent12_p[1] = bhs[0]->b_data + (offset + 1);  in fat12_ent_set_ptr()
51 		fatent->u.ent12_p[0] = bhs[0]->b_data + offset;  in fat12_ent_set_ptr()
52 		fatent->u.ent12_p[1] = bhs[1]->b_data;  in fat12_ent_set_ptr()
56 static void fat16_ent_set_ptr(struct fat_entry *fatent, int offset)  in fat16_ent_set_ptr()  argument
59 	fatent->u.ent16_p = (__le16 *)(fatent->bhs[0]->b_data + offset);  in fat16_ent_set_ptr()
62 static void fat32_ent_set_ptr(struct fat_entry *fatent, int offset)  in fat32_ent_set_ptr()  argument
65 	fatent->u.ent32_p = (__le32 *)(fatent->bhs[0]->b_data + offset);  in fat32_ent_set_ptr()
68 static int fat12_ent_bread(struct super_block *sb, struct fat_entry *fatent,  in fat12_ent_bread()  argument
71 	struct buffer_head **bhs = fatent->bhs;  in fat12_ent_bread()
74 	fatent->fat_inode = MSDOS_SB(sb)->fat_inode;  in fat12_ent_bread()
81 		fatent->nr_bhs = 1;  in fat12_ent_bread()
88 		fatent->nr_bhs = 2;  in fat12_ent_bread()
90 	fat12_ent_set_ptr(fatent, offset);  in fat12_ent_bread()
101 static int fat_ent_bread(struct super_block *sb, struct fat_entry *fatent,  in fat_ent_bread()  argument
107 	fatent->fat_inode = MSDOS_SB(sb)->fat_inode;  in fat_ent_bread()
108 	fatent->bhs[0] = sb_bread(sb, blocknr);  in fat_ent_bread()
109 	if (!fatent->bhs[0]) {  in fat_ent_bread()
114 	fatent->nr_bhs = 1;  in fat_ent_bread()
115 	ops->ent_set_ptr(fatent, offset);  in fat_ent_bread()
119 static int fat12_ent_get(struct fat_entry *fatent)  in fat12_ent_get()  argument
121 	u8 **ent12_p = fatent->u.ent12_p;  in fat12_ent_get()
125 	if (fatent->entry & 1)  in fat12_ent_get()
137 static int fat16_ent_get(struct fat_entry *fatent)  in fat16_ent_get()  argument
139 	int next = le16_to_cpu(*fatent->u.ent16_p);  in fat16_ent_get()
140 	WARN_ON((unsigned long)fatent->u.ent16_p & (2 - 1));  in fat16_ent_get()
146 static int fat32_ent_get(struct fat_entry *fatent)  in fat32_ent_get()  argument
148 	int next = le32_to_cpu(*fatent->u.ent32_p) & 0x0fffffff;  in fat32_ent_get()
149 	WARN_ON((unsigned long)fatent->u.ent32_p & (4 - 1));  in fat32_ent_get()
155 static void fat12_ent_put(struct fat_entry *fatent, int new)  in fat12_ent_put()  argument
157 	u8 **ent12_p = fatent->u.ent12_p;  in fat12_ent_put()
163 	if (fatent->entry & 1) {  in fat12_ent_put()
172 	mark_buffer_dirty_inode(fatent->bhs[0], fatent->fat_inode);  in fat12_ent_put()
173 	if (fatent->nr_bhs == 2)  in fat12_ent_put()
174 		mark_buffer_dirty_inode(fatent->bhs[1], fatent->fat_inode);  in fat12_ent_put()
177 static void fat16_ent_put(struct fat_entry *fatent, int new)  in fat16_ent_put()  argument
182 	*fatent->u.ent16_p = cpu_to_le16(new);  in fat16_ent_put()
183 	mark_buffer_dirty_inode(fatent->bhs[0], fatent->fat_inode);  in fat16_ent_put()
186 static void fat32_ent_put(struct fat_entry *fatent, int new)  in fat32_ent_put()  argument
189 	new |= le32_to_cpu(*fatent->u.ent32_p) & ~0x0fffffff;  in fat32_ent_put()
190 	*fatent->u.ent32_p = cpu_to_le32(new);  in fat32_ent_put()
191 	mark_buffer_dirty_inode(fatent->bhs[0], fatent->fat_inode);  in fat32_ent_put()
194 static int fat12_ent_next(struct fat_entry *fatent)  in fat12_ent_next()  argument
196 	u8 **ent12_p = fatent->u.ent12_p;  in fat12_ent_next()
197 	struct buffer_head **bhs = fatent->bhs;  in fat12_ent_next()
198 	u8 *nextp = ent12_p[1] + 1 + (fatent->entry & 1);  in fat12_ent_next()
200 	fatent->entry++;  in fat12_ent_next()
201 	if (fatent->nr_bhs == 1) {  in fat12_ent_next()
219 		fatent->nr_bhs = 1;  in fat12_ent_next()
227 static int fat16_ent_next(struct fat_entry *fatent)  in fat16_ent_next()  argument
229 	const struct buffer_head *bh = fatent->bhs[0];  in fat16_ent_next()
230 	fatent->entry++;  in fat16_ent_next()
231 	if (fatent->u.ent16_p < (__le16 *)(bh->b_data + (bh->b_size - 2))) {  in fat16_ent_next()
232 		fatent->u.ent16_p++;  in fat16_ent_next()
235 	fatent->u.ent16_p = NULL;  in fat16_ent_next()
239 static int fat32_ent_next(struct fat_entry *fatent)  in fat32_ent_next()  argument
241 	const struct buffer_head *bh = fatent->bhs[0];  in fat32_ent_next()
242 	fatent->entry++;  in fat32_ent_next()
243 	if (fatent->u.ent32_p < (__le32 *)(bh->b_data + (bh->b_size - 4))) {  in fat32_ent_next()
244 		fatent->u.ent32_p++;  in fat32_ent_next()
247 	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()
409 int fat_ent_write(struct inode *inode, struct fat_entry *fatent,  in fat_ent_write()  argument
416 	ops->ent_put(fatent, new);  in fat_ent_write()
418 		err = fat_sync_bhs(fatent->bhs, fatent->nr_bhs);  in fat_ent_write()
422 	return fat_mirror_bhs(sb, fatent->bhs, fatent->nr_bhs);  in fat_ent_write()
426 			       struct fat_entry *fatent)  in fat_ent_next()  argument
428 	if (sbi->fatent_ops->ent_next(fatent)) {  in fat_ent_next()
429 		if (fatent->entry < sbi->max_cluster)  in fat_ent_next()
436 				     struct fat_entry *fatent)  in fat_ent_read_block()  argument
442 	fatent_brelse(fatent);  in fat_ent_read_block()
443 	ops->ent_blocknr(sb, fatent->entry, &offset, &blocknr);  in fat_ent_read_block()
444 	return ops->ent_bread(sb, fatent, offset, blocknr);  in fat_ent_read_block()
448 			    struct fat_entry *fatent)  in fat_collect_bhs()  argument
452 	for (n = 0; n < fatent->nr_bhs; n++) {  in fat_collect_bhs()
454 			if (fatent->bhs[n] == bhs[i])  in fat_collect_bhs()
458 			get_bh(fatent->bhs[n]);  in fat_collect_bhs()
459 			bhs[i] = fatent->bhs[n];  in fat_collect_bhs()
470 	struct fat_entry fatent, prev_ent;  in fat_alloc_clusters()  local
486 	fatent_init(&fatent);  in fat_alloc_clusters()
487 	fatent_set_entry(&fatent, sbi->prev_free + 1);  in fat_alloc_clusters()
489 		if (fatent.entry >= sbi->max_cluster)  in fat_alloc_clusters()
490 			fatent.entry = FAT_START_ENT;  in fat_alloc_clusters()
491 		fatent_set_entry(&fatent, fatent.entry);  in fat_alloc_clusters()
492 		err = fat_ent_read_block(sb, &fatent);  in fat_alloc_clusters()
498 			if (ops->ent_get(&fatent) == FAT_ENT_FREE) {  in fat_alloc_clusters()
499 				int entry = fatent.entry;  in fat_alloc_clusters()
502 				ops->ent_put(&fatent, FAT_ENT_EOF);  in fat_alloc_clusters()
506 				fat_collect_bhs(bhs, &nr_bhs, &fatent);  in fat_alloc_clusters()
521 				prev_ent = fatent;  in fat_alloc_clusters()
526 		} while (fat_ent_next(sbi, &fatent));  in fat_alloc_clusters()
537 	fatent_brelse(&fatent);  in fat_alloc_clusters()
558 	struct fat_entry fatent;  in fat_free_clusters()  local
564 	fatent_init(&fatent);  in fat_free_clusters()
567 		cluster = fat_ent_read(inode, &fatent, cluster);  in fat_free_clusters()
584 			if (cluster != fatent.entry + 1) {  in fat_free_clusters()
585 				int nr_clus = fatent.entry - first_cl + 1;  in fat_free_clusters()
596 		ops->ent_put(&fatent, FAT_ENT_FREE);  in fat_free_clusters()
602 		if (nr_bhs + fatent.nr_bhs > MAX_BUF_PER_PAGE) {  in fat_free_clusters()
615 		fat_collect_bhs(bhs, &nr_bhs, &fatent);  in fat_free_clusters()
625 	fatent_brelse(&fatent);  in fat_free_clusters()
647 			struct fat_entry *fatent, int ent_limit)  in fat_ra_init()  argument
661 	if (fatent->entry >= ent_limit)  in fat_ra_init()
669 	ops->ent_blocknr(sb, fatent->entry, &offset, &blocknr);  in fat_ra_init()
683 			  struct fat_entry *fatent)  in fat_ent_reada()  argument
695 		ops->ent_blocknr(sb, fatent->entry, &offset, &blocknr);  in fat_ent_reada()
719 	struct fat_entry fatent;  in fat_count_free_clusters()  local
728 	fatent_init(&fatent);  in fat_count_free_clusters()
729 	fatent_set_entry(&fatent, FAT_START_ENT);  in fat_count_free_clusters()
730 	fat_ra_init(sb, &fatent_ra, &fatent, sbi->max_cluster);  in fat_count_free_clusters()
731 	while (fatent.entry < sbi->max_cluster) {  in fat_count_free_clusters()
733 		fat_ent_reada(sb, &fatent_ra, &fatent);  in fat_count_free_clusters()
735 		err = fat_ent_read_block(sb, &fatent);  in fat_count_free_clusters()
740 			if (ops->ent_get(&fatent) == FAT_ENT_FREE)  in fat_count_free_clusters()
742 		} while (fat_ent_next(sbi, &fatent));  in fat_count_free_clusters()
748 	fatent_brelse(&fatent);  in fat_count_free_clusters()
766 	struct fat_entry fatent;  in fat_trim_fs()  local
787 	fatent_init(&fatent);  in fat_trim_fs()
789 	fatent_set_entry(&fatent, ent_start);  in fat_trim_fs()
790 	fat_ra_init(sb, &fatent_ra, &fatent, ent_end + 1);  in fat_trim_fs()
791 	while (fatent.entry <= ent_end) {  in fat_trim_fs()
793 		fat_ent_reada(sb, &fatent_ra, &fatent);  in fat_trim_fs()
795 		err = fat_ent_read_block(sb, &fatent);  in fat_trim_fs()
799 			if (ops->ent_get(&fatent) == FAT_ENT_FREE) {  in fat_trim_fs()
803 					u32 clus = fatent.entry - free;  in fat_trim_fs()
814 		} while (fat_ent_next(sbi, &fatent) && fatent.entry <= ent_end);  in fat_trim_fs()
822 			fatent_brelse(&fatent);  in fat_trim_fs()
830 		u32 clus = fatent.entry - free;  in fat_trim_fs()
841 	fatent_brelse(&fatent);  in fat_trim_fs()