xref: /openbmc/linux/fs/minix/itree_v2.c (revision 64c70b1c)
1 #include <linux/buffer_head.h>
2 #include "minix.h"
3 
4 enum {DIRECT = 7, DEPTH = 4};	/* Have triple indirect */
5 
6 typedef u32 block_t;	/* 32 bit, host order */
7 
8 static inline unsigned long block_to_cpu(block_t n)
9 {
10 	return n;
11 }
12 
13 static inline block_t cpu_to_block(unsigned long n)
14 {
15 	return n;
16 }
17 
18 static inline block_t *i_data(struct inode *inode)
19 {
20 	return (block_t *)minix_i(inode)->u.i2_data;
21 }
22 
23 static int block_to_path(struct inode * inode, long block, int offsets[DEPTH])
24 {
25 	int n = 0;
26 	struct super_block *sb = inode->i_sb;
27 
28 	if (block < 0) {
29 		printk("minix_bmap: block<0\n");
30 	} else if (block >= (minix_sb(inode->i_sb)->s_max_size/sb->s_blocksize)) {
31 		printk("minix_bmap: block>big\n");
32 	} else if (block < 7) {
33 		offsets[n++] = block;
34 	} else if ((block -= 7) < 256) {
35 		offsets[n++] = 7;
36 		offsets[n++] = block;
37 	} else if ((block -= 256) < 256*256) {
38 		offsets[n++] = 8;
39 		offsets[n++] = block>>8;
40 		offsets[n++] = block & 255;
41 	} else {
42 		block -= 256*256;
43 		offsets[n++] = 9;
44 		offsets[n++] = block>>16;
45 		offsets[n++] = (block>>8) & 255;
46 		offsets[n++] = block & 255;
47 	}
48 	return n;
49 }
50 
51 #include "itree_common.c"
52 
53 int V2_minix_get_block(struct inode * inode, long block,
54 			struct buffer_head *bh_result, int create)
55 {
56 	return get_block(inode, block, bh_result, create);
57 }
58 
59 void V2_minix_truncate(struct inode * inode)
60 {
61 	truncate(inode);
62 }
63 
64 unsigned V2_minix_blocks(loff_t size, struct super_block *sb)
65 {
66 	return nblocks(size, sb);
67 }
68