1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/buffer_head.h>
3 #include "minix.h"
4
5 enum {DIRECT = 7, DEPTH = 4}; /* Have triple indirect */
6
7 typedef u32 block_t; /* 32 bit, host order */
8
block_to_cpu(block_t n)9 static inline unsigned long block_to_cpu(block_t n)
10 {
11 return n;
12 }
13
cpu_to_block(unsigned long n)14 static inline block_t cpu_to_block(unsigned long n)
15 {
16 return n;
17 }
18
i_data(struct inode * inode)19 static inline block_t *i_data(struct inode *inode)
20 {
21 return (block_t *)minix_i(inode)->u.i2_data;
22 }
23
24 #define DIRCOUNT 7
25 #define INDIRCOUNT(sb) (1 << ((sb)->s_blocksize_bits - 2))
26
block_to_path(struct inode * inode,long block,int offsets[DEPTH])27 static int block_to_path(struct inode * inode, long block, int offsets[DEPTH])
28 {
29 int n = 0;
30 struct super_block *sb = inode->i_sb;
31
32 if (block < 0) {
33 printk("MINIX-fs: block_to_path: block %ld < 0 on dev %pg\n",
34 block, sb->s_bdev);
35 return 0;
36 }
37 if ((u64)block * (u64)sb->s_blocksize >= sb->s_maxbytes)
38 return 0;
39
40 if (block < DIRCOUNT) {
41 offsets[n++] = block;
42 } else if ((block -= DIRCOUNT) < INDIRCOUNT(sb)) {
43 offsets[n++] = DIRCOUNT;
44 offsets[n++] = block;
45 } else if ((block -= INDIRCOUNT(sb)) < INDIRCOUNT(sb) * INDIRCOUNT(sb)) {
46 offsets[n++] = DIRCOUNT + 1;
47 offsets[n++] = block / INDIRCOUNT(sb);
48 offsets[n++] = block % INDIRCOUNT(sb);
49 } else {
50 block -= INDIRCOUNT(sb) * INDIRCOUNT(sb);
51 offsets[n++] = DIRCOUNT + 2;
52 offsets[n++] = (block / INDIRCOUNT(sb)) / INDIRCOUNT(sb);
53 offsets[n++] = (block / INDIRCOUNT(sb)) % INDIRCOUNT(sb);
54 offsets[n++] = block % INDIRCOUNT(sb);
55 }
56 return n;
57 }
58
59 #include "itree_common.c"
60
V2_minix_get_block(struct inode * inode,long block,struct buffer_head * bh_result,int create)61 int V2_minix_get_block(struct inode * inode, long block,
62 struct buffer_head *bh_result, int create)
63 {
64 return get_block(inode, block, bh_result, create);
65 }
66
V2_minix_truncate(struct inode * inode)67 void V2_minix_truncate(struct inode * inode)
68 {
69 truncate(inode);
70 }
71
V2_minix_blocks(loff_t size,struct super_block * sb)72 unsigned V2_minix_blocks(loff_t size, struct super_block *sb)
73 {
74 return nblocks(size, sb);
75 }
76