1 /*
2 * blknum.c --- Functions to handle blk64_t and high/low 64-bit block
3 * number.
4 *
5 * Copyright IBM Corporation, 2007
6 * Author Jose R. Santos <jrs@us.ibm.com>
7 *
8 * %Begin-Header%
9 * This file may be redistributed under the terms of the GNU Public
10 * License.
11 * %End-Header%
12 */
13
14 #include "config.h"
15 #include "ext2fs.h"
16
17 /*
18 * Return the group # of a block
19 */
ext2fs_group_of_blk2(ext2_filsys fs,blk64_t blk)20 dgrp_t ext2fs_group_of_blk2(ext2_filsys fs, blk64_t blk)
21 {
22 return (blk - fs->super->s_first_data_block) /
23 fs->super->s_blocks_per_group;
24 }
25
26 /*
27 * Return the first block (inclusive) in a group
28 */
ext2fs_group_first_block2(ext2_filsys fs,dgrp_t group)29 blk64_t ext2fs_group_first_block2(ext2_filsys fs, dgrp_t group)
30 {
31 return fs->super->s_first_data_block +
32 EXT2_GROUPS_TO_BLOCKS(fs->super, group);
33 }
34
35 /*
36 * Return the last block (inclusive) in a group
37 */
ext2fs_group_last_block2(ext2_filsys fs,dgrp_t group)38 blk64_t ext2fs_group_last_block2(ext2_filsys fs, dgrp_t group)
39 {
40 return (group == fs->group_desc_count - 1 ?
41 ext2fs_blocks_count(fs->super) - 1 :
42 ext2fs_group_first_block2(fs, group) +
43 (fs->super->s_blocks_per_group - 1));
44 }
45
46 /*
47 * Return the number of blocks in a group
48 */
ext2fs_group_blocks_count(ext2_filsys fs,dgrp_t group)49 int ext2fs_group_blocks_count(ext2_filsys fs, dgrp_t group)
50 {
51 int num_blocks;
52
53 if (group == fs->group_desc_count - 1) {
54 num_blocks = (ext2fs_blocks_count(fs->super) -
55 fs->super->s_first_data_block) %
56 fs->super->s_blocks_per_group;
57 if (!num_blocks)
58 num_blocks = fs->super->s_blocks_per_group;
59 } else
60 num_blocks = fs->super->s_blocks_per_group;
61
62 return num_blocks;
63 }
64
65 /*
66 * Return the inode data block count
67 */
ext2fs_inode_data_blocks2(ext2_filsys fs,struct ext2_inode * inode)68 blk64_t ext2fs_inode_data_blocks2(ext2_filsys fs,
69 struct ext2_inode *inode)
70 {
71 return (inode->i_blocks |
72 (ext2fs_has_feature_huge_file(fs->super) ?
73 (__u64) inode->osd2.linux2.l_i_blocks_hi << 32 : 0)) -
74 (inode->i_file_acl ? EXT2_CLUSTER_SIZE(fs->super) >> 9 : 0);
75 }
76
77 /*
78 * Return the inode i_blocks count
79 */
ext2fs_inode_i_blocks(ext2_filsys fs,struct ext2_inode * inode)80 blk64_t ext2fs_inode_i_blocks(ext2_filsys fs,
81 struct ext2_inode *inode)
82 {
83 return (inode->i_blocks |
84 (ext2fs_has_feature_huge_file(fs->super) ?
85 (__u64)inode->osd2.linux2.l_i_blocks_hi << 32 : 0));
86 }
87
88 /*
89 * Return the fs block count
90 */
ext2fs_blocks_count(struct ext2_super_block * super)91 blk64_t ext2fs_blocks_count(struct ext2_super_block *super)
92 {
93 return super->s_blocks_count |
94 (ext2fs_has_feature_64bit(super) ?
95 (__u64) super->s_blocks_count_hi << 32 : 0);
96 }
97
98 /*
99 * Set the fs block count
100 */
ext2fs_blocks_count_set(struct ext2_super_block * super,blk64_t blk)101 void ext2fs_blocks_count_set(struct ext2_super_block *super, blk64_t blk)
102 {
103 super->s_blocks_count = blk;
104 if (ext2fs_has_feature_64bit(super))
105 super->s_blocks_count_hi = (__u64) blk >> 32;
106 }
107
108 /*
109 * Add to the current fs block count
110 */
ext2fs_blocks_count_add(struct ext2_super_block * super,blk64_t blk)111 void ext2fs_blocks_count_add(struct ext2_super_block *super, blk64_t blk)
112 {
113 blk64_t tmp;
114 tmp = ext2fs_blocks_count(super) + blk;
115 ext2fs_blocks_count_set(super, tmp);
116 }
117
118 /*
119 * Return the fs reserved block count
120 */
ext2fs_r_blocks_count(struct ext2_super_block * super)121 blk64_t ext2fs_r_blocks_count(struct ext2_super_block *super)
122 {
123 return super->s_r_blocks_count |
124 (ext2fs_has_feature_64bit(super) ?
125 (__u64) super->s_r_blocks_count_hi << 32 : 0);
126 }
127
128 /*
129 * Set the fs reserved block count
130 */
ext2fs_r_blocks_count_set(struct ext2_super_block * super,blk64_t blk)131 void ext2fs_r_blocks_count_set(struct ext2_super_block *super, blk64_t blk)
132 {
133 super->s_r_blocks_count = blk;
134 if (ext2fs_has_feature_64bit(super))
135 super->s_r_blocks_count_hi = (__u64) blk >> 32;
136 }
137
138 /*
139 * Add to the current reserved fs block count
140 */
ext2fs_r_blocks_count_add(struct ext2_super_block * super,blk64_t blk)141 void ext2fs_r_blocks_count_add(struct ext2_super_block *super, blk64_t blk)
142 {
143 blk64_t tmp;
144 tmp = ext2fs_r_blocks_count(super) + blk;
145 ext2fs_r_blocks_count_set(super, tmp);
146 }
147
148 /*
149 * Return the fs free block count
150 */
ext2fs_free_blocks_count(struct ext2_super_block * super)151 blk64_t ext2fs_free_blocks_count(struct ext2_super_block *super)
152 {
153 return super->s_free_blocks_count |
154 (ext2fs_has_feature_64bit(super) ?
155 (__u64) super->s_free_blocks_hi << 32 : 0);
156 }
157
158 /*
159 * Set the fs free block count
160 */
ext2fs_free_blocks_count_set(struct ext2_super_block * super,blk64_t blk)161 void ext2fs_free_blocks_count_set(struct ext2_super_block *super, blk64_t blk)
162 {
163 super->s_free_blocks_count = blk;
164 if (ext2fs_has_feature_64bit(super))
165 super->s_free_blocks_hi = (__u64) blk >> 32;
166 }
167
168 /*
169 * Add to the current free fs block count
170 */
ext2fs_free_blocks_count_add(struct ext2_super_block * super,blk64_t blk)171 void ext2fs_free_blocks_count_add(struct ext2_super_block *super, blk64_t blk)
172 {
173 blk64_t tmp;
174 tmp = ext2fs_free_blocks_count(super) + blk;
175 ext2fs_free_blocks_count_set(super, tmp);
176 }
177
178 /*
179 * Get a pointer to a block group descriptor. We need the explicit
180 * pointer to the group desc for code that swaps block group
181 * descriptors before writing them out, as it wants to make a copy and
182 * do the swap there.
183 */
ext2fs_group_desc(ext2_filsys fs,struct opaque_ext2_group_desc * gdp,dgrp_t group)184 struct ext2_group_desc *ext2fs_group_desc(ext2_filsys fs,
185 struct opaque_ext2_group_desc *gdp,
186 dgrp_t group)
187 {
188 int desc_size = EXT2_DESC_SIZE(fs->super) & ~7;
189
190 return (struct ext2_group_desc *)((char *)gdp + group * desc_size);
191 }
192
193 /* Do the same but as an ext4 group desc for internal use here */
ext4fs_group_desc(ext2_filsys fs,struct opaque_ext2_group_desc * gdp,dgrp_t group)194 static struct ext4_group_desc *ext4fs_group_desc(ext2_filsys fs,
195 struct opaque_ext2_group_desc *gdp,
196 dgrp_t group)
197 {
198 return (struct ext4_group_desc *)ext2fs_group_desc(fs, gdp, group);
199 }
200
201 /*
202 * Return the block bitmap checksum of a group
203 */
ext2fs_block_bitmap_checksum(ext2_filsys fs,dgrp_t group)204 __u32 ext2fs_block_bitmap_checksum(ext2_filsys fs, dgrp_t group)
205 {
206 struct ext4_group_desc *gdp;
207 __u32 csum;
208
209 gdp = ext4fs_group_desc(fs, fs->group_desc, group);
210 csum = gdp->bg_block_bitmap_csum_lo;
211 if (EXT2_DESC_SIZE(fs->super) >= EXT4_BG_BLOCK_BITMAP_CSUM_HI_LOCATION)
212 csum |= ((__u32)gdp->bg_block_bitmap_csum_hi << 16);
213 return csum;
214 }
215
216 /*
217 * Return the block bitmap block of a group
218 */
ext2fs_block_bitmap_loc(ext2_filsys fs,dgrp_t group)219 blk64_t ext2fs_block_bitmap_loc(ext2_filsys fs, dgrp_t group)
220 {
221 struct ext4_group_desc *gdp;
222
223 gdp = ext4fs_group_desc(fs, fs->group_desc, group);
224 return gdp->bg_block_bitmap |
225 (ext2fs_has_feature_64bit(fs->super) ?
226 (__u64)gdp->bg_block_bitmap_hi << 32 : 0);
227 }
228
229 /*
230 * Set the block bitmap block of a group
231 */
ext2fs_block_bitmap_loc_set(ext2_filsys fs,dgrp_t group,blk64_t blk)232 void ext2fs_block_bitmap_loc_set(ext2_filsys fs, dgrp_t group, blk64_t blk)
233 {
234 struct ext4_group_desc *gdp;
235
236 gdp = ext4fs_group_desc(fs, fs->group_desc, group);
237 gdp->bg_block_bitmap = blk;
238 if (ext2fs_has_feature_64bit(fs->super))
239 gdp->bg_block_bitmap_hi = (__u64) blk >> 32;
240 }
241
242 /*
243 * Return the inode bitmap checksum of a group
244 */
ext2fs_inode_bitmap_checksum(ext2_filsys fs,dgrp_t group)245 __u32 ext2fs_inode_bitmap_checksum(ext2_filsys fs, dgrp_t group)
246 {
247 struct ext4_group_desc *gdp;
248 __u32 csum;
249
250 gdp = ext4fs_group_desc(fs, fs->group_desc, group);
251 csum = gdp->bg_inode_bitmap_csum_lo;
252 if (EXT2_DESC_SIZE(fs->super) >= EXT4_BG_INODE_BITMAP_CSUM_HI_END)
253 csum |= ((__u32)gdp->bg_inode_bitmap_csum_hi << 16);
254 return csum;
255 }
256
257 /*
258 * Return the inode bitmap block of a group
259 */
ext2fs_inode_bitmap_loc(ext2_filsys fs,dgrp_t group)260 blk64_t ext2fs_inode_bitmap_loc(ext2_filsys fs, dgrp_t group)
261 {
262 struct ext4_group_desc *gdp;
263
264 gdp = ext4fs_group_desc(fs, fs->group_desc, group);
265 return gdp->bg_inode_bitmap |
266 (ext2fs_has_feature_64bit(fs->super) ?
267 (__u64) gdp->bg_inode_bitmap_hi << 32 : 0);
268 }
269
270 /*
271 * Set the inode bitmap block of a group
272 */
ext2fs_inode_bitmap_loc_set(ext2_filsys fs,dgrp_t group,blk64_t blk)273 void ext2fs_inode_bitmap_loc_set(ext2_filsys fs, dgrp_t group, blk64_t blk)
274 {
275 struct ext4_group_desc *gdp;
276
277 gdp = ext4fs_group_desc(fs, fs->group_desc, group);
278 gdp->bg_inode_bitmap = blk;
279 if (ext2fs_has_feature_64bit(fs->super))
280 gdp->bg_inode_bitmap_hi = (__u64) blk >> 32;
281 }
282
283 /*
284 * Return the inode table block of a group
285 */
ext2fs_inode_table_loc(ext2_filsys fs,dgrp_t group)286 blk64_t ext2fs_inode_table_loc(ext2_filsys fs, dgrp_t group)
287 {
288 struct ext4_group_desc *gdp;
289
290 gdp = ext4fs_group_desc(fs, fs->group_desc, group);
291 return gdp->bg_inode_table |
292 (ext2fs_has_feature_64bit(fs->super) ?
293 (__u64) gdp->bg_inode_table_hi << 32 : 0);
294 }
295
296 /*
297 * Set the inode table block of a group
298 */
ext2fs_inode_table_loc_set(ext2_filsys fs,dgrp_t group,blk64_t blk)299 void ext2fs_inode_table_loc_set(ext2_filsys fs, dgrp_t group, blk64_t blk)
300 {
301 struct ext4_group_desc *gdp;
302
303 gdp = ext4fs_group_desc(fs, fs->group_desc, group);
304 gdp->bg_inode_table = blk;
305 if (ext2fs_has_feature_64bit(fs->super))
306 gdp->bg_inode_table_hi = (__u64) blk >> 32;
307 }
308
309 /*
310 * Return the free blocks count of a group
311 */
ext2fs_bg_free_blocks_count(ext2_filsys fs,dgrp_t group)312 __u32 ext2fs_bg_free_blocks_count(ext2_filsys fs, dgrp_t group)
313 {
314 struct ext4_group_desc *gdp;
315
316 gdp = ext4fs_group_desc(fs, fs->group_desc, group);
317 return gdp->bg_free_blocks_count |
318 (ext2fs_has_feature_64bit(fs->super) ?
319 (__u32) gdp->bg_free_blocks_count_hi << 16 : 0);
320 }
321
322 /*
323 * Set the free blocks count of a group
324 */
ext2fs_bg_free_blocks_count_set(ext2_filsys fs,dgrp_t group,__u32 n)325 void ext2fs_bg_free_blocks_count_set(ext2_filsys fs, dgrp_t group, __u32 n)
326 {
327 struct ext4_group_desc *gdp;
328
329 gdp = ext4fs_group_desc(fs, fs->group_desc, group);
330 gdp->bg_free_blocks_count = n;
331
332 if (ext2fs_has_feature_64bit(fs->super))
333 gdp->bg_free_blocks_count_hi = (__u32) n >> 16;
334 }
335
336 /*
337 * Return the free inodes count of a group
338 */
ext2fs_bg_free_inodes_count(ext2_filsys fs,dgrp_t group)339 __u32 ext2fs_bg_free_inodes_count(ext2_filsys fs, dgrp_t group)
340 {
341 struct ext4_group_desc *gdp;
342
343 gdp = ext4fs_group_desc(fs, fs->group_desc, group);
344 return gdp->bg_free_inodes_count |
345 (ext2fs_has_feature_64bit(fs->super) ?
346 (__u32) gdp->bg_free_inodes_count_hi << 16 : 0);
347 }
348
349 /*
350 * Set the free inodes count of a group
351 */
ext2fs_bg_free_inodes_count_set(ext2_filsys fs,dgrp_t group,__u32 n)352 void ext2fs_bg_free_inodes_count_set(ext2_filsys fs, dgrp_t group, __u32 n)
353 {
354 struct ext4_group_desc *gdp;
355
356 gdp = ext4fs_group_desc(fs, fs->group_desc, group);
357 gdp->bg_free_inodes_count = n;
358 if (ext2fs_has_feature_64bit(fs->super))
359 gdp->bg_free_inodes_count_hi = (__u32) n >> 16;
360 }
361
362 /*
363 * Return the used dirs count of a group
364 */
ext2fs_bg_used_dirs_count(ext2_filsys fs,dgrp_t group)365 __u32 ext2fs_bg_used_dirs_count(ext2_filsys fs, dgrp_t group)
366 {
367 struct ext4_group_desc *gdp;
368
369 gdp = ext4fs_group_desc(fs, fs->group_desc, group);
370 return gdp->bg_used_dirs_count |
371 (ext2fs_has_feature_64bit(fs->super) ?
372 (__u32) gdp->bg_used_dirs_count_hi << 16 : 0);
373 }
374
375 /*
376 * Set the used dirs count of a group
377 */
ext2fs_bg_used_dirs_count_set(ext2_filsys fs,dgrp_t group,__u32 n)378 void ext2fs_bg_used_dirs_count_set(ext2_filsys fs, dgrp_t group, __u32 n)
379 {
380 struct ext4_group_desc *gdp;
381
382 gdp = ext4fs_group_desc(fs, fs->group_desc, group);
383 gdp->bg_used_dirs_count = n;
384 if (ext2fs_has_feature_64bit(fs->super))
385 gdp->bg_used_dirs_count_hi = (__u32) n >> 16;
386 }
387
388 /*
389 * Return the unused inodes count of a group
390 */
ext2fs_bg_itable_unused(ext2_filsys fs,dgrp_t group)391 __u32 ext2fs_bg_itable_unused(ext2_filsys fs, dgrp_t group)
392 {
393 struct ext4_group_desc *gdp;
394
395 gdp = ext4fs_group_desc(fs, fs->group_desc, group);
396 return gdp->bg_itable_unused |
397 (ext2fs_has_feature_64bit(fs->super) ?
398 (__u32) gdp->bg_itable_unused_hi << 16 : 0);
399 }
400
401 /*
402 * Set the unused inodes count of a group
403 */
ext2fs_bg_itable_unused_set(ext2_filsys fs,dgrp_t group,__u32 n)404 void ext2fs_bg_itable_unused_set(ext2_filsys fs, dgrp_t group, __u32 n)
405 {
406 struct ext4_group_desc *gdp;
407
408 gdp = ext4fs_group_desc(fs, fs->group_desc, group);
409 gdp->bg_itable_unused = n;
410 if (ext2fs_has_feature_64bit(fs->super))
411 gdp->bg_itable_unused_hi = (__u32) n >> 16;
412 }
413
414 /*
415 * Get the flags for this block group
416 */
ext2fs_bg_flags(ext2_filsys fs,dgrp_t group)417 __u16 ext2fs_bg_flags(ext2_filsys fs, dgrp_t group)
418 {
419 struct ext4_group_desc *gdp;
420
421 gdp = ext4fs_group_desc(fs, fs->group_desc, group);
422 return gdp->bg_flags;
423 }
424
425 /*
426 * Zero out the flags for this block group
427 */
ext2fs_bg_flags_zap(ext2_filsys fs,dgrp_t group)428 void ext2fs_bg_flags_zap(ext2_filsys fs, dgrp_t group)
429 {
430 struct ext4_group_desc *gdp;
431
432 gdp = ext4fs_group_desc(fs, fs->group_desc, group);
433 gdp->bg_flags = 0;
434 return;
435 }
436
437 /*
438 * Get the value of a particular flag for this block group
439 */
ext2fs_bg_flags_test(ext2_filsys fs,dgrp_t group,__u16 bg_flag)440 int ext2fs_bg_flags_test(ext2_filsys fs, dgrp_t group, __u16 bg_flag)
441 {
442 struct ext4_group_desc *gdp;
443
444 gdp = ext4fs_group_desc(fs, fs->group_desc, group);
445 return gdp->bg_flags & bg_flag;
446 }
447
448 /*
449 * Set a flag or set of flags for this block group
450 */
ext2fs_bg_flags_set(ext2_filsys fs,dgrp_t group,__u16 bg_flags)451 void ext2fs_bg_flags_set(ext2_filsys fs, dgrp_t group, __u16 bg_flags)
452 {
453 struct ext4_group_desc *gdp;
454
455 gdp = ext4fs_group_desc(fs, fs->group_desc, group);
456 gdp->bg_flags |= bg_flags;
457 return;
458 }
459
460 /*
461 * Clear a flag or set of flags for this block group
462 */
ext2fs_bg_flags_clear(ext2_filsys fs,dgrp_t group,__u16 bg_flags)463 void ext2fs_bg_flags_clear(ext2_filsys fs, dgrp_t group, __u16 bg_flags)
464 {
465 struct ext4_group_desc *gdp;
466
467 gdp = ext4fs_group_desc(fs, fs->group_desc, group);
468 gdp->bg_flags &= ~bg_flags;
469 return;
470 }
471
472 /*
473 * Get the checksum for this block group
474 */
ext2fs_bg_checksum(ext2_filsys fs,dgrp_t group)475 __u16 ext2fs_bg_checksum(ext2_filsys fs, dgrp_t group)
476 {
477 struct ext4_group_desc *gdp;
478
479 gdp = ext4fs_group_desc(fs, fs->group_desc, group);
480 return gdp->bg_checksum;
481 }
482
483 /*
484 * Set the checksum for this block group to a previously calculated value
485 */
ext2fs_bg_checksum_set(ext2_filsys fs,dgrp_t group,__u16 checksum)486 void ext2fs_bg_checksum_set(ext2_filsys fs, dgrp_t group, __u16 checksum)
487 {
488 struct ext4_group_desc *gdp;
489
490 gdp = ext4fs_group_desc(fs, fs->group_desc, group);
491 gdp->bg_checksum = checksum;
492 return;
493 }
494
495 /*
496 * Get the acl block of a file
497 */
ext2fs_file_acl_block(ext2_filsys fs,const struct ext2_inode * inode)498 blk64_t ext2fs_file_acl_block(ext2_filsys fs, const struct ext2_inode *inode)
499 {
500 blk64_t blk = inode->i_file_acl;
501
502 if (fs && ext2fs_has_feature_64bit(fs->super))
503 blk |= ((__u64) inode->osd2.linux2.l_i_file_acl_high) << 32;
504 return blk;
505 }
506
507 /*
508 * Set the acl block of a file
509 */
ext2fs_file_acl_block_set(ext2_filsys fs,struct ext2_inode * inode,blk64_t blk)510 void ext2fs_file_acl_block_set(ext2_filsys fs, struct ext2_inode *inode,
511 blk64_t blk)
512 {
513 inode->i_file_acl = blk;
514 if (fs && ext2fs_has_feature_64bit(fs->super))
515 inode->osd2.linux2.l_i_file_acl_high = (__u64) blk >> 32;
516 }
517
518 /*
519 * Set the size of the inode
520 */
ext2fs_inode_size_set(ext2_filsys fs,struct ext2_inode * inode,ext2_off64_t size)521 errcode_t ext2fs_inode_size_set(ext2_filsys fs, struct ext2_inode *inode,
522 ext2_off64_t size)
523 {
524 /* Only regular files get to be larger than 4GB */
525 if (!LINUX_S_ISREG(inode->i_mode) && (size >> 32))
526 return EXT2_ET_FILE_TOO_BIG;
527
528 /* If we're writing a large file, set the large_file flag */
529 if (LINUX_S_ISREG(inode->i_mode) &&
530 ext2fs_needs_large_file_feature(size) &&
531 (!ext2fs_has_feature_large_file(fs->super) ||
532 fs->super->s_rev_level == EXT2_GOOD_OLD_REV)) {
533 ext2fs_set_feature_large_file(fs->super);
534 ext2fs_update_dynamic_rev(fs);
535 ext2fs_mark_super_dirty(fs);
536 }
537
538 inode->i_size = size & 0xffffffff;
539 inode->i_size_high = (size >> 32);
540
541 return 0;
542 }
543
544