xref: /linux/fs/minix/itree_v1.c (revision 8fa5723aa7e053d498336b48448b292fc2e0458b)
1 #include <linux/buffer_head.h>
2 #include "minix.h"
3 
4 enum {DEPTH = 3, DIRECT = 7};	/* Only double indirect */
5 
6 typedef u16 block_t;	/* 16 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.i1_data;
21 }
22 
23 static int block_to_path(struct inode * inode, long block, int offsets[DEPTH])
24 {
25 	int n = 0;
26 	char b[BDEVNAME_SIZE];
27 
28 	if (block < 0) {
29 		printk("MINIX-fs: block_to_path: block %ld < 0 on dev %s\n",
30 			block, bdevname(inode->i_sb->s_bdev, b));
31 	} else if (block >= (minix_sb(inode->i_sb)->s_max_size/BLOCK_SIZE)) {
32 		if (printk_ratelimit())
33 			printk("MINIX-fs: block_to_path: "
34 			       "block %ld too big on dev %s\n",
35 				block, bdevname(inode->i_sb->s_bdev, b));
36 	} else if (block < 7) {
37 		offsets[n++] = block;
38 	} else if ((block -= 7) < 512) {
39 		offsets[n++] = 7;
40 		offsets[n++] = block;
41 	} else {
42 		block -= 512;
43 		offsets[n++] = 8;
44 		offsets[n++] = block>>9;
45 		offsets[n++] = block & 511;
46 	}
47 	return n;
48 }
49 
50 #include "itree_common.c"
51 
52 int V1_minix_get_block(struct inode * inode, long block,
53 			struct buffer_head *bh_result, int create)
54 {
55 	return get_block(inode, block, bh_result, create);
56 }
57 
58 void V1_minix_truncate(struct inode * inode)
59 {
60 	truncate(inode);
61 }
62 
63 unsigned V1_minix_blocks(loff_t size, struct super_block *sb)
64 {
65 	return nblocks(size, sb);
66 }
67