xref: /openbmc/linux/fs/minix/itree_v1.c (revision b737eecd)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/buffer_head.h>
3 #include <linux/slab.h>
4 #include "minix.h"
5 
6 enum {DEPTH = 3, DIRECT = 7};	/* Only double indirect */
7 
8 typedef u16 block_t;	/* 16 bit, host order */
9 
10 static inline unsigned long block_to_cpu(block_t n)
11 {
12 	return n;
13 }
14 
15 static inline block_t cpu_to_block(unsigned long n)
16 {
17 	return n;
18 }
19 
20 static inline block_t *i_data(struct inode *inode)
21 {
22 	return (block_t *)minix_i(inode)->u.i1_data;
23 }
24 
25 static int block_to_path(struct inode * inode, long block, int offsets[DEPTH])
26 {
27 	int n = 0;
28 
29 	if (block < 0) {
30 		printk("MINIX-fs: block_to_path: block %ld < 0 on dev %pg\n",
31 			block, inode->i_sb->s_bdev);
32 		return 0;
33 	}
34 	if ((u64)block * BLOCK_SIZE >= inode->i_sb->s_maxbytes)
35 		return 0;
36 
37 	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