xref: /linux/fs/minix/itree_v1.c (revision ddb5388ffd0ad75d07e7b78181a0b579824ba6f0)
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 
28 	if (block < 0) {
29 		printk("MINIX-fs: block_to_path: block %ld < 0 on dev %pg\n",
30 			block, inode->i_sb->s_bdev);
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 %pg\n",
35 				block, inode->i_sb->s_bdev);
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