2 * gen_bitmap.c --- Generic (32-bit) bitmap routines
4 * Copyright (C) 2001 Theodore Ts'o.
7 * This file may be redistributed under the terms of the GNU Library
8 * General Public License, version 2.
25 #include <sys/types.h>
31 struct ext2fs_struct_generic_bitmap_32 {
38 errcode_t base_error_code;
42 typedef struct ext2fs_struct_generic_bitmap_32 *ext2fs_generic_bitmap_32;
44 #define EXT2FS_IS_32_BITMAP(bmap) \
45 (((bmap)->magic == EXT2_ET_MAGIC_GENERIC_BITMAP) || \
46 ((bmap)->magic == EXT2_ET_MAGIC_BLOCK_BITMAP) || \
47 ((bmap)->magic == EXT2_ET_MAGIC_INODE_BITMAP))
49 #define EXT2FS_IS_64_BITMAP(bmap) \
50 (((bmap)->magic == EXT2_ET_MAGIC_GENERIC_BITMAP64) || \
51 ((bmap)->magic == EXT2_ET_MAGIC_BLOCK_BITMAP64) || \
52 ((bmap)->magic == EXT2_ET_MAGIC_INODE_BITMAP64))
55 * Used by previously inlined function, so we have to export this and
56 * not change the function signature
58 void ext2fs_warn_bitmap2(ext2fs_generic_bitmap gen_bitmap,
59 int code, unsigned long arg)
61 ext2fs_generic_bitmap_32 bitmap = (ext2fs_generic_bitmap_32) gen_bitmap;
64 if (bitmap->description)
65 com_err(0, bitmap->base_error_code+code,
66 "#%lu for %s", arg, bitmap->description);
68 com_err(0, bitmap->base_error_code + code, "#%lu", arg);
72 static errcode_t check_magic(ext2fs_generic_bitmap bitmap)
74 if (!bitmap || !((bitmap->magic == EXT2_ET_MAGIC_GENERIC_BITMAP) ||
75 (bitmap->magic == EXT2_ET_MAGIC_INODE_BITMAP) ||
76 (bitmap->magic == EXT2_ET_MAGIC_BLOCK_BITMAP)))
77 return EXT2_ET_MAGIC_GENERIC_BITMAP;
81 errcode_t ext2fs_make_generic_bitmap(errcode_t magic, ext2_filsys fs,
82 __u32 start, __u32 end, __u32 real_end,
83 const char *descr, char *init_map,
84 ext2fs_generic_bitmap *ret)
86 ext2fs_generic_bitmap_32 bitmap;
90 retval = ext2fs_get_mem(sizeof(struct ext2fs_struct_generic_bitmap_32),
95 bitmap->magic = magic;
97 bitmap->start = start;
99 bitmap->real_end = real_end;
101 case EXT2_ET_MAGIC_INODE_BITMAP:
102 bitmap->base_error_code = EXT2_ET_BAD_INODE_MARK;
104 case EXT2_ET_MAGIC_BLOCK_BITMAP:
105 bitmap->base_error_code = EXT2_ET_BAD_BLOCK_MARK;
108 bitmap->base_error_code = EXT2_ET_BAD_GENERIC_MARK;
111 retval = ext2fs_get_mem(strlen(descr)+1, &bitmap->description);
113 ext2fs_free_mem(&bitmap);
116 strcpy(bitmap->description, descr);
118 bitmap->description = 0;
120 size = (size_t) (((bitmap->real_end - bitmap->start) / 8) + 1);
121 /* Round up to allow for the BT x86 instruction */
122 size = (size + 7) & ~3;
123 retval = ext2fs_get_mem(size, &bitmap->bitmap);
125 ext2fs_free_mem(&bitmap->description);
126 ext2fs_free_mem(&bitmap);
131 memcpy(bitmap->bitmap, init_map, size);
133 memset(bitmap->bitmap, 0, size);
134 *ret = (ext2fs_generic_bitmap) bitmap;
138 errcode_t ext2fs_allocate_generic_bitmap(__u32 start,
142 ext2fs_generic_bitmap *ret)
144 return ext2fs_make_generic_bitmap(EXT2_ET_MAGIC_GENERIC_BITMAP, 0,
145 start, end, real_end, descr, 0, ret);
148 errcode_t ext2fs_copy_generic_bitmap(ext2fs_generic_bitmap gen_src,
149 ext2fs_generic_bitmap *dest)
151 ext2fs_generic_bitmap_32 src = (ext2fs_generic_bitmap_32) gen_src;
153 return (ext2fs_make_generic_bitmap(src->magic, src->fs,
154 src->start, src->end,
156 src->description, src->bitmap,
160 void ext2fs_free_generic_bitmap(ext2fs_inode_bitmap gen_bitmap)
162 ext2fs_generic_bitmap_32 bitmap = (ext2fs_generic_bitmap_32) gen_bitmap;
164 if (check_magic(gen_bitmap))
168 if (bitmap->description) {
169 ext2fs_free_mem(&bitmap->description);
170 bitmap->description = 0;
172 if (bitmap->bitmap) {
173 ext2fs_free_mem(&bitmap->bitmap);
176 ext2fs_free_mem(&bitmap);
179 int ext2fs_test_generic_bitmap(ext2fs_generic_bitmap bitmap,
182 ext2fs_generic_bitmap_32 bitmap32 = (ext2fs_generic_bitmap_32) bitmap;
184 if (!EXT2FS_IS_32_BITMAP(bitmap)) {
185 if (EXT2FS_IS_64_BITMAP(bitmap)) {
186 ext2fs_warn_bitmap32(bitmap, __func__);
187 return ext2fs_test_generic_bmap(bitmap, bitno);
190 com_err(0, EXT2_ET_MAGIC_GENERIC_BITMAP,
191 "test_bitmap(%lu)", (unsigned long) bitno);
196 if ((bitno < bitmap32->start) || (bitno > bitmap32->end)) {
197 ext2fs_warn_bitmap2(bitmap, EXT2FS_TEST_ERROR, bitno);
200 return ext2fs_test_bit(bitno - bitmap32->start, bitmap32->bitmap);
203 int ext2fs_mark_generic_bitmap(ext2fs_generic_bitmap bitmap,
206 ext2fs_generic_bitmap_32 bitmap32 = (ext2fs_generic_bitmap_32) bitmap;
208 if (!EXT2FS_IS_32_BITMAP(bitmap)) {
209 if (EXT2FS_IS_64_BITMAP(bitmap)) {
210 ext2fs_warn_bitmap32(bitmap, __func__);
211 return ext2fs_mark_generic_bmap(bitmap, bitno);
214 com_err(0, EXT2_ET_MAGIC_GENERIC_BITMAP,
215 "mark_bitmap(%lu)", (unsigned long) bitno);
220 if ((bitno < bitmap32->start) || (bitno > bitmap32->end)) {
221 ext2fs_warn_bitmap2(bitmap, EXT2FS_MARK_ERROR, bitno);
224 return ext2fs_set_bit(bitno - bitmap32->start, bitmap32->bitmap);
227 int ext2fs_unmark_generic_bitmap(ext2fs_generic_bitmap bitmap,
230 ext2fs_generic_bitmap_32 bitmap32 = (ext2fs_generic_bitmap_32) bitmap;
232 if (!EXT2FS_IS_32_BITMAP(bitmap)) {
233 if (EXT2FS_IS_64_BITMAP(bitmap)) {
234 ext2fs_warn_bitmap32(bitmap, __func__);
235 return ext2fs_unmark_generic_bmap(bitmap, bitno);
238 com_err(0, EXT2_ET_MAGIC_GENERIC_BITMAP,
239 "mark_bitmap(%lu)", (unsigned long) bitno);
244 if ((bitno < bitmap32->start) || (bitno > bitmap32->end)) {
245 ext2fs_warn_bitmap2(bitmap, EXT2FS_UNMARK_ERROR, bitno);
248 return ext2fs_clear_bit(bitno - bitmap32->start, bitmap32->bitmap);
251 __u32 ext2fs_get_generic_bitmap_start(ext2fs_generic_bitmap bitmap)
253 ext2fs_generic_bitmap_32 bitmap32 = (ext2fs_generic_bitmap_32) bitmap;
255 if (!EXT2FS_IS_32_BITMAP(bitmap)) {
256 if (EXT2FS_IS_64_BITMAP(bitmap)) {
257 ext2fs_warn_bitmap32(bitmap, __func__);
258 return ext2fs_get_generic_bmap_start(bitmap);
261 com_err(0, EXT2_ET_MAGIC_GENERIC_BITMAP,
267 return bitmap32->start;
270 __u32 ext2fs_get_generic_bitmap_end(ext2fs_generic_bitmap bitmap)
272 ext2fs_generic_bitmap_32 bitmap32 = (ext2fs_generic_bitmap_32) bitmap;
274 if (!EXT2FS_IS_32_BITMAP(bitmap)) {
275 if (EXT2FS_IS_64_BITMAP(bitmap)) {
276 ext2fs_warn_bitmap32(bitmap, __func__);
277 return ext2fs_get_generic_bmap_end(bitmap);
280 com_err(0, EXT2_ET_MAGIC_GENERIC_BITMAP,
285 return bitmap32->end;
288 void ext2fs_clear_generic_bitmap(ext2fs_generic_bitmap bitmap)
290 ext2fs_generic_bitmap_32 bitmap32 = (ext2fs_generic_bitmap_32) bitmap;
292 if (!EXT2FS_IS_32_BITMAP(bitmap)) {
293 if (EXT2FS_IS_64_BITMAP(bitmap)) {
294 ext2fs_warn_bitmap32(bitmap, __func__);
295 ext2fs_clear_generic_bmap(bitmap);
299 com_err(0, EXT2_ET_MAGIC_GENERIC_BITMAP,
300 "clear_generic_bitmap");
305 memset(bitmap32->bitmap, 0,
306 (size_t) (((bitmap32->real_end - bitmap32->start) / 8) + 1));
309 errcode_t ext2fs_fudge_generic_bitmap_end(ext2fs_inode_bitmap gen_bitmap,
310 errcode_t magic, errcode_t neq,
311 ext2_ino_t end, ext2_ino_t *oend)
313 ext2fs_generic_bitmap_32 bitmap = (ext2fs_generic_bitmap_32) gen_bitmap;
315 EXT2_CHECK_MAGIC(bitmap, magic);
317 if (end > bitmap->real_end)
325 errcode_t ext2fs_resize_generic_bitmap(errcode_t magic,
326 __u32 new_end, __u32 new_real_end,
327 ext2fs_generic_bitmap gen_bmap)
329 ext2fs_generic_bitmap_32 bmap = (ext2fs_generic_bitmap_32) gen_bmap;
331 size_t size, new_size;
334 if (!bmap || (bmap->magic != magic))
338 * If we're expanding the bitmap, make sure all of the new
339 * parts of the bitmap are zero.
341 if (new_end > bmap->end) {
342 bitno = bmap->real_end;
345 for (; bitno > bmap->end; bitno--)
346 ext2fs_clear_bit(bitno - bmap->start, bmap->bitmap);
348 if (new_real_end == bmap->real_end) {
353 size = ((bmap->real_end - bmap->start) / 8) + 1;
354 new_size = ((new_real_end - bmap->start) / 8) + 1;
356 if (size != new_size) {
357 retval = ext2fs_resize_mem(size, new_size, &bmap->bitmap);
362 memset(bmap->bitmap + size, 0, new_size - size);
365 bmap->real_end = new_real_end;
369 errcode_t ext2fs_compare_generic_bitmap(errcode_t magic, errcode_t neq,
370 ext2fs_generic_bitmap gen_bm1,
371 ext2fs_generic_bitmap gen_bm2)
373 ext2fs_generic_bitmap_32 bm1 = (ext2fs_generic_bitmap_32) gen_bm1;
374 ext2fs_generic_bitmap_32 bm2 = (ext2fs_generic_bitmap_32) gen_bm2;
377 if (!bm1 || bm1->magic != magic)
379 if (!bm2 || bm2->magic != magic)
382 if ((bm1->start != bm2->start) ||
383 (bm1->end != bm2->end) ||
384 (memcmp(bm1->bitmap, bm2->bitmap,
385 (size_t) (bm1->end - bm1->start)/8)))
388 for (i = bm1->end - ((bm1->end - bm1->start) % 8); i <= bm1->end; i++)
389 if (ext2fs_fast_test_block_bitmap(gen_bm1, i) !=
390 ext2fs_fast_test_block_bitmap(gen_bm2, i))
396 void ext2fs_set_generic_bitmap_padding(ext2fs_generic_bitmap gen_map)
398 ext2fs_generic_bitmap_32 map = (ext2fs_generic_bitmap_32) gen_map;
401 /* Protect loop from wrap-around if map->real_end is maxed */
402 for (i=map->end+1, j = i - map->start;
403 i <= map->real_end && i > map->end;
405 ext2fs_set_bit(j, map->bitmap);
408 errcode_t ext2fs_get_generic_bitmap_range(ext2fs_generic_bitmap gen_bmap,
410 __u32 start, __u32 num,
413 ext2fs_generic_bitmap_32 bmap = (ext2fs_generic_bitmap_32) gen_bmap;
415 if (!bmap || (bmap->magic != magic))
418 if ((start < bmap->start) || (start+num-1 > bmap->real_end))
419 return EXT2_ET_INVALID_ARGUMENT;
421 memcpy(out, bmap->bitmap + ((start - bmap->start) >> 3), (num+7) >> 3);
425 errcode_t ext2fs_set_generic_bitmap_range(ext2fs_generic_bitmap gen_bmap,
427 __u32 start, __u32 num,
430 ext2fs_generic_bitmap_32 bmap = (ext2fs_generic_bitmap_32) gen_bmap;
432 if (!bmap || (bmap->magic != magic))
435 if ((start < bmap->start) || (start+num-1 > bmap->real_end))
436 return EXT2_ET_INVALID_ARGUMENT;
438 memcpy(bmap->bitmap + ((start - bmap->start) >> 3), in, (num+7) >> 3);
443 * Compare @mem to zero buffer by 256 bytes.
444 * Return 1 if @mem is zeroed memory, otherwise return 0.
446 int ext2fs_mem_is_zero(const char *mem, size_t len)
448 static const char zero_buf[256];
450 while (len >= sizeof(zero_buf)) {
451 if (memcmp(mem, zero_buf, sizeof(zero_buf)))
453 len -= sizeof(zero_buf);
454 mem += sizeof(zero_buf);
456 /* Deal with leftover bytes. */
458 return !memcmp(mem, zero_buf, len);
463 * Return true if all of the bits in a specified range are clear
465 static int ext2fs_test_clear_generic_bitmap_range(ext2fs_generic_bitmap gen_bitmap,
469 ext2fs_generic_bitmap_32 bitmap = (ext2fs_generic_bitmap_32) gen_bitmap;
470 size_t start_byte, len_byte = len >> 3;
471 unsigned int start_bit, len_bit = len % 8;
477 const char *ADDR = bitmap->bitmap;
479 start -= bitmap->start;
480 start_byte = start >> 3;
481 start_bit = start % 8;
483 if (start_bit != 0) {
485 * The compared start block number or start inode number
486 * is not the first bit in a byte.
488 mark_count = 8 - start_bit;
489 if (len < 8 - start_bit) {
490 mark_count = (int)len;
491 mark_bit = len + start_bit - 1;
495 for (i = mark_count; i > 0; i--, mark_bit--)
496 first_bit |= 1 << mark_bit;
499 * Compare blocks or inodes in the first byte.
500 * If there is any marked bit, this function returns 0.
502 if (first_bit & ADDR[start_byte])
504 else if (len <= 8 - start_bit)
508 len_bit = (len - mark_count) % 8;
509 len_byte = (len - mark_count) >> 3;
513 * The compared start block number or start inode number is
514 * the first bit in a byte.
518 * The compared end block number or end inode number is
519 * not the last bit in a byte.
521 for (mark_bit = len_bit - 1; mark_bit >= 0; mark_bit--)
522 last_bit |= 1 << mark_bit;
525 * Compare blocks or inodes in the last byte.
526 * If there is any marked bit, this function returns 0.
528 if (last_bit & ADDR[start_byte + len_byte])
530 else if (len_byte == 0)
534 /* Check whether all bytes are 0 */
535 return ext2fs_mem_is_zero(ADDR + start_byte, len_byte);
538 errcode_t ext2fs_find_first_zero_generic_bitmap(ext2fs_generic_bitmap gen_bitmap,
539 __u32 start, __u32 end,
542 ext2fs_generic_bitmap_32 bitmap = (ext2fs_generic_bitmap_32) gen_bitmap;
545 if (start < bitmap->start || end > bitmap->end || start > end) {
546 ext2fs_warn_bitmap2(gen_bitmap, EXT2FS_TEST_ERROR, start);
550 while (start <= end) {
551 b = ext2fs_test_bit(start - bitmap->start, bitmap->bitmap);
562 errcode_t ext2fs_find_first_set_generic_bitmap(ext2fs_generic_bitmap gen_bitmap,
563 __u32 start, __u32 end,
566 ext2fs_generic_bitmap_32 bitmap = (ext2fs_generic_bitmap_32) gen_bitmap;
569 if (start < bitmap->start || end > bitmap->end || start > end) {
570 ext2fs_warn_bitmap2(gen_bitmap, EXT2FS_TEST_ERROR, start);
574 while (start <= end) {
575 b = ext2fs_test_bit(start - bitmap->start, bitmap->bitmap);
586 int ext2fs_test_block_bitmap_range(ext2fs_block_bitmap gen_bitmap,
587 blk_t block, int num)
589 ext2fs_generic_bitmap_32 bitmap = (ext2fs_generic_bitmap_32) gen_bitmap;
591 EXT2_CHECK_MAGIC(bitmap, EXT2_ET_MAGIC_BLOCK_BITMAP);
592 if ((block < bitmap->start) || (block > bitmap->real_end) ||
593 (block+num-1 > bitmap->real_end)) {
594 ext2fs_warn_bitmap(EXT2_ET_BAD_BLOCK_TEST,
595 block, bitmap->description);
598 return ext2fs_test_clear_generic_bitmap_range((ext2fs_generic_bitmap)
602 int ext2fs_test_inode_bitmap_range(ext2fs_inode_bitmap gen_bitmap,
603 ext2_ino_t inode, int num)
605 ext2fs_generic_bitmap_32 bitmap = (ext2fs_generic_bitmap_32) gen_bitmap;
607 EXT2_CHECK_MAGIC(bitmap, EXT2_ET_MAGIC_INODE_BITMAP);
608 if ((inode < bitmap->start) || (inode > bitmap->real_end) ||
609 (inode+num-1 > bitmap->real_end)) {
610 ext2fs_warn_bitmap(EXT2_ET_BAD_INODE_TEST,
611 inode, bitmap->description);
614 return ext2fs_test_clear_generic_bitmap_range((ext2fs_generic_bitmap)
618 void ext2fs_mark_block_bitmap_range(ext2fs_block_bitmap gen_bitmap,
619 blk_t block, int num)
621 ext2fs_generic_bitmap_32 bitmap = (ext2fs_generic_bitmap_32) gen_bitmap;
624 if ((block < bitmap->start) || (block > bitmap->end) ||
625 (block+num-1 > bitmap->end)) {
626 ext2fs_warn_bitmap(EXT2_ET_BAD_BLOCK_MARK, block,
627 bitmap->description);
630 for (i=0; i < num; i++)
631 ext2fs_fast_set_bit(block + i - bitmap->start, bitmap->bitmap);
634 void ext2fs_unmark_block_bitmap_range(ext2fs_block_bitmap gen_bitmap,
635 blk_t block, int num)
637 ext2fs_generic_bitmap_32 bitmap = (ext2fs_generic_bitmap_32) gen_bitmap;
640 if ((block < bitmap->start) || (block > bitmap->end) ||
641 (block+num-1 > bitmap->end)) {
642 ext2fs_warn_bitmap(EXT2_ET_BAD_BLOCK_UNMARK, block,
643 bitmap->description);
646 for (i=0; i < num; i++)
647 ext2fs_fast_clear_bit(block + i - bitmap->start,