fs/tfs/ialloc.c

   1 #include <stdio.h>
   2 #include <malloc.h>
   3 #include <bitopts.h>
   4 #include <tfs.h>
   5
   6
   7 static void * tfs_read_inode_bitmap(struct tfs_sb_info *sbi)
   8 {
   9         char *buf = malloc(sbi->s_block_size);
  10
  11         tfs_bread(sbi, sbi->s_inode_bitmap, buf);
  12
  13         return buf;
  14 }
  15
  16 /*
  17  * free an inode, return -1 if failed, or return 9
  18  */
  19 int tfs_free_inode(struct tfs_sb_info *sbi, int inr)
  20 {
  21         char *bitmap = tfs_read_inode_bitmap(sbi);
  22
  23         /* inode number count from 1 */
  24         if (clear_bit(bitmap, inr - 1) == 0) {
  25                 printk("ERROR: trying to free an unallocated inode!\n");
  26                 free(bitmap);
  27                 return -1;
  28         }
  29
  30         tfs_bwrite(sbi, sbi->s_inode_bitmap, bitmap);
  31         free(bitmap);
  32         return 0;
  33 }
  34
  35 int tfs_alloc_inode(struct tfs_sb_info *sbi, int inr)
  36 {
  37         char *bitmap;
  38
  39         if (inr < 0) {
  40                 printk("ERROR: trying to alloc a negtive inode!\n");
  41                 return -1;
  42         }
  43
  44         bitmap = tfs_read_inode_bitmap(sbi);
  45         /* try the target first */
  46         if (test_bit(bitmap, inr - 1) != 0)
  47                 inr = find_first_zero(bitmap, bitmap + sbi->s_block_size) + 1;
  48         if (inr != -1) {
  49                 set_bit(bitmap, inr - 1);
  50                 tfs_bwrite(sbi, sbi->s_inode_bitmap, bitmap);
  51         }
  52
  53         free(bitmap);
  54         return inr;
  55 }