1#include <linux/buffer_head.h>
2#include "minix.h"
3
4enum {DIRECT = 7, DEPTH = 4};	/* Have triple indirect */
5
6typedef u32 block_t;	/* 32 bit, host order */
7
8static inline unsigned long block_to_cpu(block_t n)
9{
10	return n;
11}
12
13static inline block_t cpu_to_block(unsigned long n)
14{
15	return n;
16}
17
18static inline block_t *i_data(struct inode *inode)
19{
20	return (block_t *)minix_i(inode)->u.i2_data;
21}
22
23#define DIRCOUNT 7
24#define INDIRCOUNT(sb) (1 << ((sb)->s_blocksize_bits - 2))
25
26static int block_to_path(struct inode * inode, long block, int offsets[DEPTH])
27{
28	int n = 0;
29	char b[BDEVNAME_SIZE];
30	struct super_block *sb = inode->i_sb;
31
32	if (block < 0) {
33		printk("MINIX-fs: block_to_path: block %ld < 0 on dev %s\n",
34			block, bdevname(sb->s_bdev, b));
35	} else if ((u64)block * (u64)sb->s_blocksize >=
36			minix_sb(sb)->s_max_size) {
37		if (printk_ratelimit())
38			printk("MINIX-fs: block_to_path: "
39			       "block %ld too big on dev %s\n",
40				block, bdevname(sb->s_bdev, b));
41	} else if (block < DIRCOUNT) {
42		offsets[n++] = block;
43	} else if ((block -= DIRCOUNT) < INDIRCOUNT(sb)) {
44		offsets[n++] = DIRCOUNT;
45		offsets[n++] = block;
46	} else if ((block -= INDIRCOUNT(sb)) < INDIRCOUNT(sb) * INDIRCOUNT(sb)) {
47		offsets[n++] = DIRCOUNT + 1;
48		offsets[n++] = block / INDIRCOUNT(sb);
49		offsets[n++] = block % INDIRCOUNT(sb);
50	} else {
51		block -= INDIRCOUNT(sb) * INDIRCOUNT(sb);
52		offsets[n++] = DIRCOUNT + 2;
53		offsets[n++] = (block / INDIRCOUNT(sb)) / INDIRCOUNT(sb);
54		offsets[n++] = (block / INDIRCOUNT(sb)) % INDIRCOUNT(sb);
55		offsets[n++] = block % INDIRCOUNT(sb);
56	}
57	return n;
58}
59
60#include "itree_common.c"
61
62int V2_minix_get_block(struct inode * inode, long block,
63			struct buffer_head *bh_result, int create)
64{
65	return get_block(inode, block, bh_result, create);
66}
67
68void V2_minix_truncate(struct inode * inode)
69{
70	truncate(inode);
71}
72
73unsigned V2_minix_blocks(loff_t size, struct super_block *sb)
74{
75	return nblocks(size, sb);
76}
77