LXR linux/fs/minix/itree

   1#include <linux/buffer_head.h>
   2#include "minix.h"
   3
   4enum {DIRECT = 7, DEPTH = 4};   /* Have triple indirect */
   5
   6typedef u32 block_t;    /* 32 bit, host order */
   7
   8static inline unsigned long block_to_cpu(block_t n)
   9{
  10        return n;
  11}
  12
  13static inline block_t cpu_to_block(unsigned long n)
  14{
  15        return n;
  16}
  17
  18static inline block_t *i_data(struct inode *inode)
  19{
  20        return (block_t *)minix_i(inode)->u.i2_data;
  21}
  22
  23static int block_to_path(struct inode * inode, long block, int offsets[DEPTH])
  24{
  25        int n = 0;
  26        char b[BDEVNAME_SIZE];
  27        struct super_block *sb = inode->i_sb;
  28
  29        if (block < 0) {
  30                printk("MINIX-fs: block_to_path: block %ld < 0 on dev %s\n",
  31                        block, bdevname(sb->s_bdev, b));
  32        } else if (block >= (minix_sb(inode->i_sb)->s_max_size/sb->s_blocksize)) {
  33                if (printk_ratelimit())
  34                        printk("MINIX-fs: block_to_path: "
  35                               "block %ld too big on dev %s\n",
  36                                block, bdevname(sb->s_bdev, b));
  37        } else if (block < 7) {
  38                offsets[n++] = block;
  39        } else if ((block -= 7) < 256) {
  40                offsets[n++] = 7;
  41                offsets[n++] = block;
  42        } else if ((block -= 256) < 256*256) {
  43                offsets[n++] = 8;
  44                offsets[n++] = block>>8;
  45                offsets[n++] = block & 255;
  46        } else {
  47                block -= 256*256;
  48                offsets[n++] = 9;
  49                offsets[n++] = block>>16;
  50                offsets[n++] = (block>>8) & 255;
  51                offsets[n++] = block & 255;
  52        }
  53        return n;
  54}
  55
  56#include "itree_common.c"
  57
  58int V2_minix_get_block(struct inode * inode, long block,
  59                        struct buffer_head *bh_result, int create)
  60{
  61        return get_block(inode, block, bh_result, create);
  62}
  63
  64void V2_minix_truncate(struct inode * inode)
  65{
  66        truncate(inode);
  67}
  68
  69unsigned V2_minix_blocks(loff_t size, struct super_block *sb)
  70{
  71        return nblocks(size, sb);
  72}
  73