1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0
2*4882a593Smuzhiyun #include <linux/buffer_head.h>
3*4882a593Smuzhiyun #include "minix.h"
4*4882a593Smuzhiyun
5*4882a593Smuzhiyun enum {DIRECT = 7, DEPTH = 4}; /* Have triple indirect */
6*4882a593Smuzhiyun
7*4882a593Smuzhiyun typedef u32 block_t; /* 32 bit, host order */
8*4882a593Smuzhiyun
block_to_cpu(block_t n)9*4882a593Smuzhiyun static inline unsigned long block_to_cpu(block_t n)
10*4882a593Smuzhiyun {
11*4882a593Smuzhiyun return n;
12*4882a593Smuzhiyun }
13*4882a593Smuzhiyun
cpu_to_block(unsigned long n)14*4882a593Smuzhiyun static inline block_t cpu_to_block(unsigned long n)
15*4882a593Smuzhiyun {
16*4882a593Smuzhiyun return n;
17*4882a593Smuzhiyun }
18*4882a593Smuzhiyun
i_data(struct inode * inode)19*4882a593Smuzhiyun static inline block_t *i_data(struct inode *inode)
20*4882a593Smuzhiyun {
21*4882a593Smuzhiyun return (block_t *)minix_i(inode)->u.i2_data;
22*4882a593Smuzhiyun }
23*4882a593Smuzhiyun
24*4882a593Smuzhiyun #define DIRCOUNT 7
25*4882a593Smuzhiyun #define INDIRCOUNT(sb) (1 << ((sb)->s_blocksize_bits - 2))
26*4882a593Smuzhiyun
block_to_path(struct inode * inode,long block,int offsets[DEPTH])27*4882a593Smuzhiyun static int block_to_path(struct inode * inode, long block, int offsets[DEPTH])
28*4882a593Smuzhiyun {
29*4882a593Smuzhiyun int n = 0;
30*4882a593Smuzhiyun struct super_block *sb = inode->i_sb;
31*4882a593Smuzhiyun
32*4882a593Smuzhiyun if (block < 0) {
33*4882a593Smuzhiyun printk("MINIX-fs: block_to_path: block %ld < 0 on dev %pg\n",
34*4882a593Smuzhiyun block, sb->s_bdev);
35*4882a593Smuzhiyun return 0;
36*4882a593Smuzhiyun }
37*4882a593Smuzhiyun if ((u64)block * (u64)sb->s_blocksize >= sb->s_maxbytes)
38*4882a593Smuzhiyun return 0;
39*4882a593Smuzhiyun
40*4882a593Smuzhiyun if (block < DIRCOUNT) {
41*4882a593Smuzhiyun offsets[n++] = block;
42*4882a593Smuzhiyun } else if ((block -= DIRCOUNT) < INDIRCOUNT(sb)) {
43*4882a593Smuzhiyun offsets[n++] = DIRCOUNT;
44*4882a593Smuzhiyun offsets[n++] = block;
45*4882a593Smuzhiyun } else if ((block -= INDIRCOUNT(sb)) < INDIRCOUNT(sb) * INDIRCOUNT(sb)) {
46*4882a593Smuzhiyun offsets[n++] = DIRCOUNT + 1;
47*4882a593Smuzhiyun offsets[n++] = block / INDIRCOUNT(sb);
48*4882a593Smuzhiyun offsets[n++] = block % INDIRCOUNT(sb);
49*4882a593Smuzhiyun } else {
50*4882a593Smuzhiyun block -= INDIRCOUNT(sb) * INDIRCOUNT(sb);
51*4882a593Smuzhiyun offsets[n++] = DIRCOUNT + 2;
52*4882a593Smuzhiyun offsets[n++] = (block / INDIRCOUNT(sb)) / INDIRCOUNT(sb);
53*4882a593Smuzhiyun offsets[n++] = (block / INDIRCOUNT(sb)) % INDIRCOUNT(sb);
54*4882a593Smuzhiyun offsets[n++] = block % INDIRCOUNT(sb);
55*4882a593Smuzhiyun }
56*4882a593Smuzhiyun return n;
57*4882a593Smuzhiyun }
58*4882a593Smuzhiyun
59*4882a593Smuzhiyun #include "itree_common.c"
60*4882a593Smuzhiyun
V2_minix_get_block(struct inode * inode,long block,struct buffer_head * bh_result,int create)61*4882a593Smuzhiyun int V2_minix_get_block(struct inode * inode, long block,
62*4882a593Smuzhiyun struct buffer_head *bh_result, int create)
63*4882a593Smuzhiyun {
64*4882a593Smuzhiyun return get_block(inode, block, bh_result, create);
65*4882a593Smuzhiyun }
66*4882a593Smuzhiyun
V2_minix_truncate(struct inode * inode)67*4882a593Smuzhiyun void V2_minix_truncate(struct inode * inode)
68*4882a593Smuzhiyun {
69*4882a593Smuzhiyun truncate(inode);
70*4882a593Smuzhiyun }
71*4882a593Smuzhiyun
V2_minix_blocks(loff_t size,struct super_block * sb)72*4882a593Smuzhiyun unsigned V2_minix_blocks(loff_t size, struct super_block *sb)
73*4882a593Smuzhiyun {
74*4882a593Smuzhiyun return nblocks(size, sb);
75*4882a593Smuzhiyun }
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