xref: /linux/fs/minix/itree_v1.c (revision d524dac9279b6a41ffdf7ff7958c577f2e387db6)
1 #include <linux/buffer_head.h>
2 #include <linux/slab.h>
3 #include "minix.h"
4 
5 enum {DEPTH = 3, DIRECT = 7};	/* Only double indirect */
6 
7 typedef u16 block_t;	/* 16 bit, host order */
8 
9 static inline unsigned long block_to_cpu(block_t n)
10 {
11 	return n;
12 }
13 
14 static inline block_t cpu_to_block(unsigned long n)
15 {
16 	return n;
17 }
18 
19 static inline block_t *i_data(struct inode *inode)
20 {
21 	return (block_t *)minix_i(inode)->u.i1_data;
22 }
23 
24 static int block_to_path(struct inode * inode, long block, int offsets[DEPTH])
25 {
26 	int n = 0;
27 	char b[BDEVNAME_SIZE];
28 
29 	if (block < 0) {
30 		printk("MINIX-fs: block_to_path: block %ld < 0 on dev %s\n",
31 			block, bdevname(inode->i_sb->s_bdev, b));
32 	} else if (block >= (minix_sb(inode->i_sb)->s_max_size/BLOCK_SIZE)) {
33 		if (printk_ratelimit())
34 			printk("MINIX-fs: block_to_path: "
35 			       "block %ld too big on dev %s\n",
36 				block, bdevname(inode->i_sb->s_bdev, b));
37 	} else if (block < 7) {
38 		offsets[n++] = block;
39 	} else if ((block -= 7) < 512) {
40 		offsets[n++] = 7;
41 		offsets[n++] = block;
42 	} else {
43 		block -= 512;
44 		offsets[n++] = 8;
45 		offsets[n++] = block>>9;
46 		offsets[n++] = block & 511;
47 	}
48 	return n;
49 }
50 
51 #include "itree_common.c"
52 
53 int V1_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 V1_minix_truncate(struct inode * inode)
60 {
61 	truncate(inode);
62 }
63 
64 unsigned V1_minix_blocks(loff_t size, struct super_block *sb)
65 {
66 	return nblocks(size, sb);
67 }
68