1 /* vi: set sw=4 ts=4: */
3 * alloc.c --- allocate new inodes, blocks for ext2fs
5 * Copyright (C) 1993, 1994, 1995, 1996 Theodore Ts'o.
8 * This file may be redistributed under the terms of the GNU Public
24 #include <sys/types.h>
31 * Right now, just search forward from the parent directory's block
32 * group to find the next free inode.
34 * Should have a special policy for directories.
36 errcode_t ext2fs_new_inode(ext2_filsys fs, ext2_ino_t dir,
37 int mode EXT2FS_ATTR((unused)),
38 ext2fs_inode_bitmap map, ext2_ino_t *ret)
40 ext2_ino_t dir_group = 0;
42 ext2_ino_t start_inode;
44 EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
49 return EXT2_ET_NO_INODE_BITMAP;
52 dir_group = (dir - 1) / EXT2_INODES_PER_GROUP(fs->super);
54 start_inode = (dir_group * EXT2_INODES_PER_GROUP(fs->super)) + 1;
55 if (start_inode < EXT2_FIRST_INODE(fs->super))
56 start_inode = EXT2_FIRST_INODE(fs->super);
60 if (!ext2fs_fast_test_inode_bitmap(map, i))
63 if (i > fs->super->s_inodes_count)
64 i = EXT2_FIRST_INODE(fs->super);
65 } while (i != start_inode);
67 if (ext2fs_test_inode_bitmap(map, i))
68 return EXT2_ET_INODE_ALLOC_FAIL;
74 * Stupid algorithm --- we now just search forward starting from the
75 * goal. Should put in a smarter one someday....
77 errcode_t ext2fs_new_block(ext2_filsys fs, blk_t goal,
78 ext2fs_block_bitmap map, blk_t *ret)
82 EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
87 return EXT2_ET_NO_BLOCK_BITMAP;
88 if (!goal || (goal >= fs->super->s_blocks_count))
89 goal = fs->super->s_first_data_block;
92 if (!ext2fs_fast_test_block_bitmap(map, i)) {
97 if (i >= fs->super->s_blocks_count)
98 i = fs->super->s_first_data_block;
100 return EXT2_ET_BLOCK_ALLOC_FAIL;
104 * This function zeros out the allocated block, and updates all of the
105 * appropriate filesystem records.
107 errcode_t ext2fs_alloc_block(ext2_filsys fs, blk_t goal,
108 char *block_buf, blk_t *ret)
115 retval = ext2fs_get_mem(fs->blocksize, &buf);
120 memset(block_buf, 0, fs->blocksize);
122 if (!fs->block_map) {
123 retval = ext2fs_read_block_bitmap(fs);
128 retval = ext2fs_new_block(fs, goal, 0, &block);
132 retval = io_channel_write_blk(fs->io, block, 1, block_buf);
136 ext2fs_block_alloc_stats(fs, block, +1);
142 ext2fs_free_mem(&buf);
146 errcode_t ext2fs_get_free_blocks(ext2_filsys fs, blk_t start, blk_t finish,
147 int num, ext2fs_block_bitmap map, blk_t *ret)
151 EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
156 return EXT2_ET_NO_BLOCK_BITMAP;
158 b = fs->super->s_first_data_block;
164 if (b+num-1 > fs->super->s_blocks_count)
165 b = fs->super->s_first_data_block;
166 if (ext2fs_fast_test_block_bitmap_range(map, b, num)) {
171 } while (b != finish);
172 return EXT2_ET_BLOCK_ALLOC_FAIL;