fs/minix/itree_v1.c

   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 }