* Copyright (C) 2001 Theodore Ts'o.
*
* %Begin-Header%
- * This file may be redistributed under the terms of the GNU Public
- * License.
+ * This file may be redistributed under the terms of the GNU Library
+ * General Public License, version 2.
* %End-Header%
*/
+#include "config.h"
#include <stdio.h>
#include <string.h>
#if HAVE_UNISTD_H
#endif
#include "ext2_fs.h"
-#include "ext2fs.h"
+#include "ext2fsP.h"
struct ext2fs_struct_generic_bitmap {
errcode_t magic;
__u32 reserved[7];
};
+#define EXT2FS_IS_32_BITMAP(bmap) \
+ (((bmap)->magic == EXT2_ET_MAGIC_GENERIC_BITMAP) || \
+ ((bmap)->magic == EXT2_ET_MAGIC_BLOCK_BITMAP) || \
+ ((bmap)->magic == EXT2_ET_MAGIC_INODE_BITMAP))
+
+#define EXT2FS_IS_64_BITMAP(bmap) \
+ (((bmap)->magic == EXT2_ET_MAGIC_GENERIC_BITMAP64) || \
+ ((bmap)->magic == EXT2_ET_MAGIC_BLOCK_BITMAP64) || \
+ ((bmap)->magic == EXT2_ET_MAGIC_INODE_BITMAP64))
+
/*
* Used by previously inlined function, so we have to export this and
* not change the function signature
bitmap->description = 0;
size = (size_t) (((bitmap->real_end - bitmap->start) / 8) + 1);
+ /* Round up to allow for the BT x86 instruction */
+ size = (size + 7) & ~3;
retval = ext2fs_get_mem(size, &bitmap->bitmap);
if (retval) {
ext2fs_free_mem(&bitmap->description);
int ext2fs_test_generic_bitmap(ext2fs_generic_bitmap bitmap,
blk_t bitno)
{
+ if (!EXT2FS_IS_32_BITMAP(bitmap)) {
+ if (EXT2FS_IS_64_BITMAP(bitmap)) {
+ ext2fs_warn_bitmap32(bitmap, __func__);
+ return ext2fs_test_generic_bmap(bitmap, bitno);
+ }
+#ifndef OMIT_COM_ERR
+ com_err(0, EXT2_ET_MAGIC_GENERIC_BITMAP,
+ "test_bitmap(%lu)", (unsigned long) bitno);
+#endif
+ return 0;
+ }
+
if ((bitno < bitmap->start) || (bitno > bitmap->end)) {
ext2fs_warn_bitmap2(bitmap, EXT2FS_TEST_ERROR, bitno);
return 0;
int ext2fs_mark_generic_bitmap(ext2fs_generic_bitmap bitmap,
__u32 bitno)
{
+ if (!EXT2FS_IS_32_BITMAP(bitmap)) {
+ if (EXT2FS_IS_64_BITMAP(bitmap)) {
+ ext2fs_warn_bitmap32(bitmap, __func__);
+ return ext2fs_mark_generic_bmap(bitmap, bitno);
+ }
+#ifndef OMIT_COM_ERR
+ com_err(0, EXT2_ET_MAGIC_GENERIC_BITMAP,
+ "mark_bitmap(%lu)", (unsigned long) bitno);
+#endif
+ return 0;
+ }
+
if ((bitno < bitmap->start) || (bitno > bitmap->end)) {
ext2fs_warn_bitmap2(bitmap, EXT2FS_MARK_ERROR, bitno);
return 0;
int ext2fs_unmark_generic_bitmap(ext2fs_generic_bitmap bitmap,
blk_t bitno)
{
+ if (!EXT2FS_IS_32_BITMAP(bitmap)) {
+ if (EXT2FS_IS_64_BITMAP(bitmap)) {
+ ext2fs_warn_bitmap32(bitmap, __func__);
+ return ext2fs_unmark_generic_bmap(bitmap, bitno);
+ }
+#ifndef OMIT_COM_ERR
+ com_err(0, EXT2_ET_MAGIC_GENERIC_BITMAP,
+ "mark_bitmap(%lu)", (unsigned long) bitno);
+#endif
+ return 0;
+ }
+
if ((bitno < bitmap->start) || (bitno > bitmap->end)) {
ext2fs_warn_bitmap2(bitmap, EXT2FS_UNMARK_ERROR, bitno);
return 0;
__u32 ext2fs_get_generic_bitmap_start(ext2fs_generic_bitmap bitmap)
{
+ if (!EXT2FS_IS_32_BITMAP(bitmap)) {
+ if (EXT2FS_IS_64_BITMAP(bitmap)) {
+ ext2fs_warn_bitmap32(bitmap, __func__);
+ return ext2fs_get_generic_bmap_start(bitmap);
+ }
+#ifndef OMIT_COM_ERR
+ com_err(0, EXT2_ET_MAGIC_GENERIC_BITMAP,
+ "get_bitmap_start");
+#endif
+ return 0;
+ }
+
return bitmap->start;
}
__u32 ext2fs_get_generic_bitmap_end(ext2fs_generic_bitmap bitmap)
{
+ if (!EXT2FS_IS_32_BITMAP(bitmap)) {
+ if (EXT2FS_IS_64_BITMAP(bitmap)) {
+ ext2fs_warn_bitmap32(bitmap, __func__);
+ return ext2fs_get_generic_bmap_end(bitmap);
+ }
+#ifndef OMIT_COM_ERR
+ com_err(0, EXT2_ET_MAGIC_GENERIC_BITMAP,
+ "get_bitmap_end");
+#endif
+ return 0;
+ }
return bitmap->end;
}
void ext2fs_clear_generic_bitmap(ext2fs_generic_bitmap bitmap)
{
- if (check_magic(bitmap))
+ if (!EXT2FS_IS_32_BITMAP(bitmap)) {
+ if (EXT2FS_IS_64_BITMAP(bitmap)) {
+ ext2fs_warn_bitmap32(bitmap, __func__);
+ ext2fs_clear_generic_bmap(bitmap);
+ return;
+ }
+#ifndef OMIT_COM_ERR
+ com_err(0, EXT2_ET_MAGIC_GENERIC_BITMAP,
+ "clear_generic_bitmap");
+#endif
return;
+ }
memset(bitmap->bitmap, 0,
(size_t) (((bitmap->real_end - bitmap->start) / 8) + 1));
return 0;
}
+/*
+ * Compare @mem to zero buffer by 256 bytes.
+ * Return 1 if @mem is zeroed memory, otherwise return 0.
+ */
+int ext2fs_mem_is_zero(const char *mem, size_t len)
+{
+ static const char zero_buf[256];
+
+ while (len >= sizeof(zero_buf)) {
+ if (memcmp(mem, zero_buf, sizeof(zero_buf)))
+ return 0;
+ len -= sizeof(zero_buf);
+ mem += sizeof(zero_buf);
+ }
+ /* Deal with leftover bytes. */
+ if (len)
+ return !memcmp(mem, zero_buf, len);
+ return 1;
+}
+
+/*
+ * Return true if all of the bits in a specified range are clear
+ */
+static int ext2fs_test_clear_generic_bitmap_range(ext2fs_generic_bitmap bitmap,
+ unsigned int start,
+ unsigned int len)
+{
+ size_t start_byte, len_byte = len >> 3;
+ unsigned int start_bit, len_bit = len % 8;
+ int first_bit = 0;
+ int last_bit = 0;
+ int mark_count = 0;
+ int mark_bit = 0;
+ int i;
+ const char *ADDR = bitmap->bitmap;
+
+ start -= bitmap->start;
+ start_byte = start >> 3;
+ start_bit = start % 8;
+
+ if (start_bit != 0) {
+ /*
+ * The compared start block number or start inode number
+ * is not the first bit in a byte.
+ */
+ mark_count = 8 - start_bit;
+ if (len < 8 - start_bit) {
+ mark_count = (int)len;
+ mark_bit = len + start_bit - 1;
+ } else
+ mark_bit = 7;
+
+ for (i = mark_count; i > 0; i--, mark_bit--)
+ first_bit |= 1 << mark_bit;
+
+ /*
+ * Compare blocks or inodes in the first byte.
+ * If there is any marked bit, this function returns 0.
+ */
+ if (first_bit & ADDR[start_byte])
+ return 0;
+ else if (len <= 8 - start_bit)
+ return 1;
+
+ start_byte++;
+ len_bit = (len - mark_count) % 8;
+ len_byte = (len - mark_count) >> 3;
+ }
+
+ /*
+ * The compared start block number or start inode number is
+ * the first bit in a byte.
+ */
+ if (len_bit != 0) {
+ /*
+ * The compared end block number or end inode number is
+ * not the last bit in a byte.
+ */
+ for (mark_bit = len_bit - 1; mark_bit >= 0; mark_bit--)
+ last_bit |= 1 << mark_bit;
+
+ /*
+ * Compare blocks or inodes in the last byte.
+ * If there is any marked bit, this function returns 0.
+ */
+ if (last_bit & ADDR[start_byte + len_byte])
+ return 0;
+ else if (len_byte == 0)
+ return 1;
+ }
+
+ /* Check whether all bytes are 0 */
+ return ext2fs_mem_is_zero(ADDR + start_byte, len_byte);
+}
+
+errcode_t ext2fs_find_first_zero_generic_bitmap(ext2fs_generic_bitmap bitmap,
+ __u32 start, __u32 end,
+ __u32 *out)
+{
+ blk_t b;
+
+ if (start < bitmap->start || end > bitmap->end || start > end) {
+ ext2fs_warn_bitmap2(bitmap, EXT2FS_TEST_ERROR, start);
+ return EINVAL;
+ }
+
+ while (start <= end) {
+ b = ext2fs_test_bit(start - bitmap->start, bitmap->bitmap);
+ if (!b) {
+ *out = start;
+ return 0;
+ }
+ start++;
+ }
+
+ return ENOENT;
+}
+
+errcode_t ext2fs_find_first_set_generic_bitmap(ext2fs_generic_bitmap bitmap,
+ __u32 start, __u32 end,
+ __u32 *out)
+{
+ blk_t b;
+
+ if (start < bitmap->start || end > bitmap->end || start > end) {
+ ext2fs_warn_bitmap2(bitmap, EXT2FS_TEST_ERROR, start);
+ return EINVAL;
+ }
+
+ while (start <= end) {
+ b = ext2fs_test_bit(start - bitmap->start, bitmap->bitmap);
+ if (b) {
+ *out = start;
+ return 0;
+ }
+ start++;
+ }
+
+ return ENOENT;
+}
+
int ext2fs_test_block_bitmap_range(ext2fs_block_bitmap bitmap,
blk_t block, int num)
{
- int i;
-
+ EXT2_CHECK_MAGIC(bitmap, EXT2_ET_MAGIC_BLOCK_BITMAP);
if ((block < bitmap->start) || (block+num-1 > bitmap->real_end)) {
ext2fs_warn_bitmap(EXT2_ET_BAD_BLOCK_TEST,
block, bitmap->description);
return 0;
}
- for (i=0; i < num; i++) {
- if (ext2fs_fast_test_block_bitmap(bitmap, block+i))
- return 0;
+ return ext2fs_test_clear_generic_bitmap_range((ext2fs_generic_bitmap)
+ bitmap, block, num);
+}
+
+int ext2fs_test_inode_bitmap_range(ext2fs_inode_bitmap bitmap,
+ ino_t inode, int num)
+{
+ EXT2_CHECK_MAGIC(bitmap, EXT2_ET_MAGIC_INODE_BITMAP);
+ if ((inode < bitmap->start) || (inode+num-1 > bitmap->real_end)) {
+ ext2fs_warn_bitmap(EXT2_ET_BAD_INODE_TEST,
+ inode, bitmap->description);
+ return 0;
}
- return 1;
+ return ext2fs_test_clear_generic_bitmap_range((ext2fs_generic_bitmap)
+ bitmap, inode, num);
}
void ext2fs_mark_block_bitmap_range(ext2fs_block_bitmap bitmap,
ext2fs_fast_clear_bit(block + i - bitmap->start,
bitmap->bitmap);
}
+