2 * rw_bitmaps.c --- routines to read and write the inode and block bitmaps.
4 * Copyright (C) 1993, 1994, 1994, 1996 Theodore Ts'o.
7 * This file may be redistributed under the terms of the GNU Library
8 * General Public License, version 2.
20 #ifdef HAVE_SYS_STAT_H
23 #ifdef HAVE_SYS_TYPES_H
24 #include <sys/types.h>
31 static errcode_t write_bitmaps(ext2_filsys fs, int do_inode, int do_block)
35 int block_nbytes, inode_nbytes;
38 char *block_buf = NULL, *inode_buf = NULL;
41 blk64_t blk_itr = EXT2FS_B2C(fs, fs->super->s_first_data_block);
42 ext2_ino_t ino_itr = 1;
44 EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
46 if (!(fs->flags & EXT2_FLAG_RW))
47 return EXT2_ET_RO_FILSYS;
49 csum_flag = ext2fs_has_group_desc_csum(fs);
51 inode_nbytes = block_nbytes = 0;
53 block_nbytes = EXT2_CLUSTERS_PER_GROUP(fs->super) / 8;
54 retval = io_channel_alloc_buf(fs->io, 0, &block_buf);
57 memset(block_buf, 0xff, fs->blocksize);
60 inode_nbytes = (size_t)
61 ((EXT2_INODES_PER_GROUP(fs->super)+7) / 8);
62 retval = io_channel_alloc_buf(fs->io, 0, &inode_buf);
65 memset(inode_buf, 0xff, fs->blocksize);
68 for (i = 0; i < fs->group_desc_count; i++) {
70 goto skip_block_bitmap;
72 if (csum_flag && ext2fs_bg_flags_test(fs, i, EXT2_BG_BLOCK_UNINIT)
74 goto skip_this_block_bitmap;
76 retval = ext2fs_get_block_bitmap_range2(fs->block_map,
77 blk_itr, block_nbytes << 3, block_buf);
81 if (i == fs->group_desc_count - 1) {
82 /* Force bitmap padding for the last group */
83 nbits = EXT2FS_NUM_B2C(fs,
84 ((ext2fs_blocks_count(fs->super)
85 - (__u64) fs->super->s_first_data_block)
86 % (__u64) EXT2_BLOCKS_PER_GROUP(fs->super)));
88 for (j = nbits; j < fs->blocksize * 8; j++)
89 ext2fs_set_bit(j, block_buf);
92 retval = ext2fs_block_bitmap_csum_set(fs, i, block_buf,
96 ext2fs_group_desc_csum_set(fs, i);
97 fs->flags |= EXT2_FLAG_DIRTY;
99 blk = ext2fs_block_bitmap_loc(fs, i);
101 retval = io_channel_write_blk64(fs->io, blk, 1,
104 retval = EXT2_ET_BLOCK_BITMAP_WRITE;
108 skip_this_block_bitmap:
109 blk_itr += block_nbytes << 3;
115 if (csum_flag && ext2fs_bg_flags_test(fs, i, EXT2_BG_INODE_UNINIT)
117 goto skip_this_inode_bitmap;
119 retval = ext2fs_get_inode_bitmap_range2(fs->inode_map,
120 ino_itr, inode_nbytes << 3, inode_buf);
124 retval = ext2fs_inode_bitmap_csum_set(fs, i, inode_buf,
128 ext2fs_group_desc_csum_set(fs, i);
129 fs->flags |= EXT2_FLAG_DIRTY;
131 blk = ext2fs_inode_bitmap_loc(fs, i);
133 retval = io_channel_write_blk64(fs->io, blk, 1,
136 retval = EXT2_ET_INODE_BITMAP_WRITE;
140 skip_this_inode_bitmap:
141 ino_itr += inode_nbytes << 3;
145 fs->flags &= ~EXT2_FLAG_BB_DIRTY;
146 ext2fs_free_mem(&block_buf);
149 fs->flags &= ~EXT2_FLAG_IB_DIRTY;
150 ext2fs_free_mem(&inode_buf);
155 ext2fs_free_mem(&inode_buf);
157 ext2fs_free_mem(&block_buf);
161 static errcode_t mark_uninit_bg_group_blocks(ext2_filsys fs)
165 ext2fs_block_bitmap bmap = fs->block_map;
167 for (i = 0; i < fs->group_desc_count; i++) {
168 if (!ext2fs_bg_flags_test(fs, i, EXT2_BG_BLOCK_UNINIT))
171 ext2fs_reserve_super_and_bgd(fs, i, bmap);
174 * Mark the blocks used for the inode table
176 blk = ext2fs_inode_table_loc(fs, i);
178 ext2fs_mark_block_bitmap_range2(bmap, blk,
179 fs->inode_blocks_per_group);
182 * Mark block used for the block bitmap
184 blk = ext2fs_block_bitmap_loc(fs, i);
186 ext2fs_mark_block_bitmap2(bmap, blk);
189 * Mark block used for the inode bitmap
191 blk = ext2fs_inode_bitmap_loc(fs, i);
193 ext2fs_mark_block_bitmap2(bmap, blk);
198 static int bitmap_tail_verify(unsigned char *bitmap, int first, int last)
202 for (i = first; i <= last; i++)
203 if (bitmap[i] != 0xff)
208 static errcode_t read_bitmaps(ext2_filsys fs, int do_inode, int do_block)
211 char *block_bitmap = 0, *inode_bitmap = 0;
214 int block_nbytes = EXT2_CLUSTERS_PER_GROUP(fs->super) / 8;
215 int inode_nbytes = EXT2_INODES_PER_GROUP(fs->super) / 8;
220 blk64_t blk_itr = EXT2FS_B2C(fs, fs->super->s_first_data_block);
222 ext2_ino_t ino_itr = 1;
225 EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
227 if ((block_nbytes > (int) fs->blocksize) ||
228 (inode_nbytes > (int) fs->blocksize))
229 return EXT2_ET_CORRUPT_SUPERBLOCK;
231 fs->write_bitmaps = ext2fs_write_bitmaps;
233 csum_flag = ext2fs_has_group_desc_csum(fs);
235 retval = ext2fs_get_mem(strlen(fs->device_name) + 80, &buf);
240 ext2fs_free_block_bitmap(fs->block_map);
241 strcpy(buf, "block bitmap for ");
242 strcat(buf, fs->device_name);
243 retval = ext2fs_allocate_block_bitmap(fs, buf, &fs->block_map);
246 retval = io_channel_alloc_buf(fs->io, 0, &block_bitmap);
253 ext2fs_free_inode_bitmap(fs->inode_map);
254 strcpy(buf, "inode bitmap for ");
255 strcat(buf, fs->device_name);
256 retval = ext2fs_allocate_inode_bitmap(fs, buf, &fs->inode_map);
259 retval = io_channel_alloc_buf(fs->io, 0, &inode_bitmap);
264 ext2fs_free_mem(&buf);
266 if (fs->flags & EXT2_FLAG_IMAGE_FILE) {
267 blk = (ext2fs_le32_to_cpu(fs->image_header->offset_inodemap) / fs->blocksize);
268 ino_cnt = fs->super->s_inodes_count;
269 while (inode_bitmap && ino_cnt > 0) {
270 retval = io_channel_read_blk64(fs->image_io, blk++,
274 cnt = fs->blocksize << 3;
277 retval = ext2fs_set_inode_bitmap_range2(fs->inode_map,
278 ino_itr, cnt, inode_bitmap);
284 blk = (ext2fs_le32_to_cpu(fs->image_header->offset_blockmap) /
286 blk_cnt = EXT2_GROUPS_TO_CLUSTERS(fs->super,
287 fs->group_desc_count);
288 while (block_bitmap && blk_cnt > 0) {
289 retval = io_channel_read_blk64(fs->image_io, blk++,
293 cnt = fs->blocksize << 3;
296 retval = ext2fs_set_block_bitmap_range2(fs->block_map,
297 blk_itr, cnt, block_bitmap);
303 goto success_cleanup;
306 for (i = 0; i < fs->group_desc_count; i++) {
308 blk = ext2fs_block_bitmap_loc(fs, i);
310 ext2fs_bg_flags_test(fs, i, EXT2_BG_BLOCK_UNINIT) &&
311 ext2fs_group_desc_csum_verify(fs, i)) ||
312 (blk >= ext2fs_blocks_count(fs->super)))
315 retval = io_channel_read_blk64(fs->io, blk,
318 retval = EXT2_ET_BLOCK_BITMAP_READ;
321 /* verify block bitmap checksum */
323 EXT2_FLAG_IGNORE_CSUM_ERRORS) &&
324 !ext2fs_block_bitmap_csum_verify(fs, i,
325 block_bitmap, block_nbytes)) {
327 EXT2_ET_BLOCK_BITMAP_CSUM_INVALID;
330 if (!bitmap_tail_verify((unsigned char *) block_bitmap,
331 block_nbytes, fs->blocksize - 1))
332 tail_flags |= EXT2_FLAG_BBITMAP_TAIL_PROBLEM;
334 memset(block_bitmap, 0, block_nbytes);
335 cnt = block_nbytes << 3;
336 retval = ext2fs_set_block_bitmap_range2(fs->block_map,
337 blk_itr, cnt, block_bitmap);
340 blk_itr += block_nbytes << 3;
343 blk = ext2fs_inode_bitmap_loc(fs, i);
345 ext2fs_bg_flags_test(fs, i, EXT2_BG_INODE_UNINIT) &&
346 ext2fs_group_desc_csum_verify(fs, i)) ||
347 (blk >= ext2fs_blocks_count(fs->super)))
350 retval = io_channel_read_blk64(fs->io, blk,
353 retval = EXT2_ET_INODE_BITMAP_READ;
357 /* verify inode bitmap checksum */
359 EXT2_FLAG_IGNORE_CSUM_ERRORS) &&
360 !ext2fs_inode_bitmap_csum_verify(fs, i,
361 inode_bitmap, inode_nbytes)) {
363 EXT2_ET_INODE_BITMAP_CSUM_INVALID;
366 if (!bitmap_tail_verify((unsigned char *) inode_bitmap,
367 inode_nbytes, fs->blocksize - 1))
368 tail_flags |= EXT2_FLAG_IBITMAP_TAIL_PROBLEM;
370 memset(inode_bitmap, 0, inode_nbytes);
371 cnt = inode_nbytes << 3;
372 retval = ext2fs_set_inode_bitmap_range2(fs->inode_map,
373 ino_itr, cnt, inode_bitmap);
376 ino_itr += inode_nbytes << 3;
380 /* Mark group blocks for any BLOCK_UNINIT groups */
382 retval = mark_uninit_bg_group_blocks(fs);
389 ext2fs_free_mem(&inode_bitmap);
390 fs->flags &= ~EXT2_FLAG_IBITMAP_TAIL_PROBLEM;
393 ext2fs_free_mem(&block_bitmap);
394 fs->flags &= ~EXT2_FLAG_BBITMAP_TAIL_PROBLEM;
396 fs->flags |= tail_flags;
401 ext2fs_free_block_bitmap(fs->block_map);
405 ext2fs_free_inode_bitmap(fs->inode_map);
409 ext2fs_free_mem(&inode_bitmap);
411 ext2fs_free_mem(&block_bitmap);
413 ext2fs_free_mem(&buf);
417 errcode_t ext2fs_read_inode_bitmap(ext2_filsys fs)
419 return read_bitmaps(fs, 1, 0);
422 errcode_t ext2fs_read_block_bitmap(ext2_filsys fs)
424 return read_bitmaps(fs, 0, 1);
427 errcode_t ext2fs_write_inode_bitmap(ext2_filsys fs)
429 return write_bitmaps(fs, 1, 0);
432 errcode_t ext2fs_write_block_bitmap (ext2_filsys fs)
434 return write_bitmaps(fs, 0, 1);
437 errcode_t ext2fs_read_bitmaps(ext2_filsys fs)
439 if (fs->inode_map && fs->block_map)
442 return read_bitmaps(fs, !fs->inode_map, !fs->block_map);
445 errcode_t ext2fs_write_bitmaps(ext2_filsys fs)
447 int do_inode = fs->inode_map && ext2fs_test_ib_dirty(fs);
448 int do_block = fs->block_map && ext2fs_test_bb_dirty(fs);
450 if (!do_inode && !do_block)
453 return write_bitmaps(fs, do_inode, do_block);