xref: /aosp_15_r20/external/e2fsprogs/resize/resize2fs.c (revision 6a54128f25917bfc36a8a6e9d722c04a0b4641b6)
1 /*
2  * resize2fs.c --- ext2 main routine
3  *
4  * Copyright (C) 1997, 1998 by Theodore Ts'o and
5  * 	PowerQuest, Inc.
6  *
7  * Copyright (C) 1999, 2000 by Theodore Ts'o
8  *
9  * %Begin-Header%
10  * This file may be redistributed under the terms of the GNU Public
11  * License.
12  * %End-Header%
13  */
14 
15 /*
16  * Resizing a filesystem consists of the following phases:
17  *
18  *	1.  Adjust superblock and write out new parts of the inode
19  * 		table
20  * 	2.  Determine blocks which need to be relocated, and copy the
21  * 		contents of blocks from their old locations to the new ones.
22  * 	3.  Scan the inode table, doing the following:
23  * 		a.  If blocks have been moved, update the block
24  * 			pointers in the inodes and indirect blocks to
25  * 			point at the new block locations.
26  * 		b.  If parts of the inode table need to be evacuated,
27  * 			copy inodes from their old locations to their
28  * 			new ones.
29  * 		c.  If (b) needs to be done, note which blocks contain
30  * 			directory information, since we will need to
31  * 			update the directory information.
32  * 	4.  Update the directory blocks with the new inode locations.
33  * 	5.  Move the inode tables, if necessary.
34  */
35 
36 #include "config.h"
37 #include "resize2fs.h"
38 #include <time.h>
39 
40 #ifdef __linux__			/* Kludge for debugging */
41 #define RESIZE2FS_DEBUG
42 #endif
43 
44 static void fix_uninit_block_bitmaps(ext2_filsys fs);
45 static errcode_t adjust_superblock(ext2_resize_t rfs, blk64_t new_size);
46 static errcode_t blocks_to_move(ext2_resize_t rfs);
47 static errcode_t block_mover(ext2_resize_t rfs);
48 static errcode_t inode_scan_and_fix(ext2_resize_t rfs);
49 static errcode_t inode_ref_fix(ext2_resize_t rfs);
50 static errcode_t move_itables(ext2_resize_t rfs);
51 static errcode_t fix_resize_inode(ext2_filsys fs);
52 static errcode_t resize2fs_calculate_summary_stats(ext2_filsys fs);
53 static errcode_t fix_sb_journal_backup(ext2_filsys fs);
54 static errcode_t mark_table_blocks(ext2_filsys fs,
55 				   ext2fs_block_bitmap bmap);
56 static errcode_t clear_sparse_super2_last_group(ext2_resize_t rfs);
57 static errcode_t reserve_sparse_super2_last_group(ext2_resize_t rfs,
58 						 ext2fs_block_bitmap meta_bmap);
59 static errcode_t resize_group_descriptors(ext2_resize_t rfs, blk64_t new_size);
60 static errcode_t move_bg_metadata(ext2_resize_t rfs);
61 static errcode_t zero_high_bits_in_inodes(ext2_resize_t rfs);
62 
63 /*
64  * Some helper functions to check if a block is in a metadata area
65  */
is_block_bm(ext2_filsys fs,unsigned int grp,blk64_t blk)66 static inline int is_block_bm(ext2_filsys fs, unsigned int grp, blk64_t blk)
67 {
68 	return blk == ext2fs_block_bitmap_loc(fs, grp);
69 }
70 
is_inode_bm(ext2_filsys fs,unsigned int grp,blk64_t blk)71 static inline int is_inode_bm(ext2_filsys fs, unsigned int grp, blk64_t blk)
72 {
73 	return blk == ext2fs_inode_bitmap_loc(fs, grp);
74 }
75 
is_inode_tb(ext2_filsys fs,unsigned int grp,blk64_t blk)76 static int is_inode_tb(ext2_filsys fs, unsigned int grp, blk64_t blk)
77 {
78 	return blk >= ext2fs_inode_table_loc(fs, grp) &&
79 	       blk < (ext2fs_inode_table_loc(fs, grp) +
80 		      fs->inode_blocks_per_group);
81 }
82 
83 /* Some bigalloc helper macros which are more succinct... */
84 #define B2C(x)	EXT2FS_B2C(fs, (x))
85 #define C2B(x)	EXT2FS_C2B(fs, (x))
86 #define EQ_CLSTR(x, y) (B2C(x) == B2C(y))
87 #define LE_CLSTR(x, y) (B2C(x) <= B2C(y))
88 #define LT_CLSTR(x, y) (B2C(x) <  B2C(y))
89 #define GE_CLSTR(x, y) (B2C(x) >= B2C(y))
90 #define GT_CLSTR(x, y) (B2C(x) >  B2C(y))
91 
92 static int lazy_itable_init;
93 
94 /*
95  * This is the top-level routine which does the dirty deed....
96  */
resize_fs(ext2_filsys fs,blk64_t * new_size,int flags,errcode_t (* progress)(ext2_resize_t rfs,int pass,unsigned long cur,unsigned long max_val))97 errcode_t resize_fs(ext2_filsys fs, blk64_t *new_size, int flags,
98 	    errcode_t (*progress)(ext2_resize_t rfs, int pass,
99 					  unsigned long cur,
100 					  unsigned long max_val))
101 {
102 	ext2_resize_t	rfs;
103 	errcode_t	retval;
104 	struct resource_track	rtrack, overall_track;
105 
106 	/*
107 	 * Create the data structure
108 	 */
109 	retval = ext2fs_get_mem(sizeof(struct ext2_resize_struct), &rfs);
110 	if (retval)
111 		return retval;
112 
113 	memset(rfs, 0, sizeof(struct ext2_resize_struct));
114 	fs->priv_data = rfs;
115 	rfs->old_fs = fs;
116 	rfs->flags = flags;
117 	rfs->itable_buf	 = 0;
118 	rfs->progress = progress;
119 
120 	init_resource_track(&overall_track, "overall resize2fs", fs->io);
121 	init_resource_track(&rtrack, "read_bitmaps", fs->io);
122 	retval = ext2fs_read_bitmaps(fs);
123 	if (retval)
124 		goto errout;
125 	print_resource_track(rfs, &rtrack, fs->io);
126 
127 	fs->super->s_state |= EXT2_ERROR_FS;
128 	ext2fs_mark_super_dirty(fs);
129 	ext2fs_flush(fs);
130 
131 	init_resource_track(&rtrack, "fix_uninit_block_bitmaps 1", fs->io);
132 	fix_uninit_block_bitmaps(fs);
133 	print_resource_track(rfs, &rtrack, fs->io);
134 	retval = ext2fs_dup_handle(fs, &rfs->new_fs);
135 	if (retval)
136 		goto errout;
137 
138 	init_resource_track(&rtrack, "resize_group_descriptors", fs->io);
139 	retval = resize_group_descriptors(rfs, *new_size);
140 	if (retval)
141 		goto errout;
142 	print_resource_track(rfs, &rtrack, fs->io);
143 
144 	init_resource_track(&rtrack, "move_bg_metadata", fs->io);
145 	retval = move_bg_metadata(rfs);
146 	if (retval)
147 		goto errout;
148 	print_resource_track(rfs, &rtrack, fs->io);
149 
150 	init_resource_track(&rtrack, "zero_high_bits_in_metadata", fs->io);
151 	retval = zero_high_bits_in_inodes(rfs);
152 	if (retval)
153 		goto errout;
154 	print_resource_track(rfs, &rtrack, fs->io);
155 
156 	init_resource_track(&rtrack, "adjust_superblock", fs->io);
157 	retval = adjust_superblock(rfs, *new_size);
158 	if (retval)
159 		goto errout;
160 	print_resource_track(rfs, &rtrack, fs->io);
161 
162 	init_resource_track(&rtrack, "fix_uninit_block_bitmaps 2", fs->io);
163 	fix_uninit_block_bitmaps(rfs->new_fs);
164 	print_resource_track(rfs, &rtrack, fs->io);
165 	/* Clear the block bitmap uninit flag for the last block group */
166 	ext2fs_bg_flags_clear(rfs->new_fs, rfs->new_fs->group_desc_count - 1,
167 			     EXT2_BG_BLOCK_UNINIT);
168 
169 	*new_size = ext2fs_blocks_count(rfs->new_fs->super);
170 
171 	init_resource_track(&rtrack, "blocks_to_move", fs->io);
172 	retval = blocks_to_move(rfs);
173 	if (retval)
174 		goto errout;
175 	print_resource_track(rfs, &rtrack, fs->io);
176 
177 #ifdef RESIZE2FS_DEBUG
178 	if (rfs->flags & RESIZE_DEBUG_BMOVE)
179 		printf("Number of free blocks: %llu/%llu, Needed: %llu\n",
180 		       (unsigned long long) ext2fs_free_blocks_count(rfs->old_fs->super),
181 		       (unsigned long long) ext2fs_free_blocks_count(rfs->new_fs->super),
182 		       (unsigned long long) rfs->needed_blocks);
183 #endif
184 
185 	init_resource_track(&rtrack, "block_mover", fs->io);
186 	retval = block_mover(rfs);
187 	if (retval)
188 		goto errout;
189 	print_resource_track(rfs, &rtrack, fs->io);
190 
191 	init_resource_track(&rtrack, "inode_scan_and_fix", fs->io);
192 	retval = inode_scan_and_fix(rfs);
193 	if (retval)
194 		goto errout;
195 	print_resource_track(rfs, &rtrack, fs->io);
196 
197 	init_resource_track(&rtrack, "inode_ref_fix", fs->io);
198 	retval = inode_ref_fix(rfs);
199 	if (retval)
200 		goto errout;
201 	print_resource_track(rfs, &rtrack, fs->io);
202 
203 	init_resource_track(&rtrack, "move_itables", fs->io);
204 	retval = move_itables(rfs);
205 	if (retval)
206 		goto errout;
207 	print_resource_track(rfs, &rtrack, fs->io);
208 
209 	retval = clear_sparse_super2_last_group(rfs);
210 	if (retval)
211 		goto errout;
212 
213 	init_resource_track(&rtrack, "calculate_summary_stats", fs->io);
214 	retval = resize2fs_calculate_summary_stats(rfs->new_fs);
215 	if (retval)
216 		goto errout;
217 	print_resource_track(rfs, &rtrack, fs->io);
218 
219 	init_resource_track(&rtrack, "fix_resize_inode", fs->io);
220 	retval = fix_resize_inode(rfs->new_fs);
221 	if (retval)
222 		goto errout;
223 	print_resource_track(rfs, &rtrack, fs->io);
224 
225 	init_resource_track(&rtrack, "fix_sb_journal_backup", fs->io);
226 	retval = fix_sb_journal_backup(rfs->new_fs);
227 	if (retval)
228 		goto errout;
229 	print_resource_track(rfs, &rtrack, fs->io);
230 
231 	retval = ext2fs_set_gdt_csum(rfs->new_fs);
232 	if (retval)
233 		goto errout;
234 
235 	rfs->new_fs->super->s_state &= ~EXT2_ERROR_FS;
236 	rfs->new_fs->flags &= ~EXT2_FLAG_MASTER_SB_ONLY;
237 
238 	print_resource_track(rfs, &overall_track, fs->io);
239 	retval = ext2fs_close_free(&rfs->new_fs);
240 	if (retval)
241 		goto errout;
242 
243 	rfs->flags = flags;
244 
245 	ext2fs_free(rfs->old_fs);
246 	rfs->old_fs = NULL;
247 	if (rfs->itable_buf)
248 		ext2fs_free_mem(&rfs->itable_buf);
249 	if (rfs->reserve_blocks)
250 		ext2fs_free_block_bitmap(rfs->reserve_blocks);
251 	if (rfs->move_blocks)
252 		ext2fs_free_block_bitmap(rfs->move_blocks);
253 	ext2fs_free_mem(&rfs);
254 
255 	return 0;
256 
257 errout:
258 	if (rfs->new_fs) {
259 		ext2fs_free(rfs->new_fs);
260 		rfs->new_fs = NULL;
261 	}
262 	if (rfs->itable_buf)
263 		ext2fs_free_mem(&rfs->itable_buf);
264 	ext2fs_free_mem(&rfs);
265 	return retval;
266 }
267 
268 /* Keep the size of the group descriptor region constant */
adjust_reserved_gdt_blocks(ext2_filsys old_fs,ext2_filsys fs)269 static void adjust_reserved_gdt_blocks(ext2_filsys old_fs, ext2_filsys fs)
270 {
271 	if (ext2fs_has_feature_resize_inode(fs->super) &&
272 	    (old_fs->desc_blocks != fs->desc_blocks)) {
273 		int new;
274 
275 		new = ((int) fs->super->s_reserved_gdt_blocks) +
276 			(old_fs->desc_blocks - fs->desc_blocks);
277 		if (new < 0)
278 			new = 0;
279 		if (new > (int) fs->blocksize/4)
280 			new = fs->blocksize/4;
281 		fs->super->s_reserved_gdt_blocks = new;
282 	}
283 }
284 
285 /* Toggle 64bit mode */
resize_group_descriptors(ext2_resize_t rfs,blk64_t new_size)286 static errcode_t resize_group_descriptors(ext2_resize_t rfs, blk64_t new_size)
287 {
288 	void *o, *n, *new_group_desc;
289 	dgrp_t i;
290 	int copy_size;
291 	errcode_t retval;
292 
293 	if (!(rfs->flags & (RESIZE_DISABLE_64BIT | RESIZE_ENABLE_64BIT)))
294 		return 0;
295 
296 	if (new_size != ext2fs_blocks_count(rfs->new_fs->super) ||
297 	    ext2fs_blocks_count(rfs->new_fs->super) >= (1ULL << 32) ||
298 	    (rfs->flags & RESIZE_DISABLE_64BIT &&
299 	     rfs->flags & RESIZE_ENABLE_64BIT))
300 		return EXT2_ET_INVALID_ARGUMENT;
301 
302 	if (rfs->flags & RESIZE_DISABLE_64BIT) {
303 		ext2fs_clear_feature_64bit(rfs->new_fs->super);
304 		rfs->new_fs->super->s_desc_size = EXT2_MIN_DESC_SIZE;
305 	} else if (rfs->flags & RESIZE_ENABLE_64BIT) {
306 		ext2fs_set_feature_64bit(rfs->new_fs->super);
307 		rfs->new_fs->super->s_desc_size = EXT2_MIN_DESC_SIZE_64BIT;
308 	}
309 
310 	if (EXT2_DESC_SIZE(rfs->old_fs->super) ==
311 	    EXT2_DESC_SIZE(rfs->new_fs->super))
312 		return 0;
313 
314 	o = rfs->new_fs->group_desc;
315 	rfs->new_fs->desc_blocks = ext2fs_div_ceil(
316 			rfs->old_fs->group_desc_count,
317 			EXT2_DESC_PER_BLOCK(rfs->new_fs->super));
318 	retval = ext2fs_get_arrayzero(rfs->new_fs->desc_blocks,
319 				      rfs->old_fs->blocksize, &new_group_desc);
320 	if (retval)
321 		return retval;
322 
323 	n = new_group_desc;
324 
325 	if (EXT2_DESC_SIZE(rfs->old_fs->super) <=
326 	    EXT2_DESC_SIZE(rfs->new_fs->super))
327 		copy_size = EXT2_DESC_SIZE(rfs->old_fs->super);
328 	else
329 		copy_size = EXT2_DESC_SIZE(rfs->new_fs->super);
330 	for (i = 0; i < rfs->old_fs->group_desc_count; i++) {
331 		memcpy(n, o, copy_size);
332 		n = (char *)n + EXT2_DESC_SIZE(rfs->new_fs->super);
333 		o = (char *)o + EXT2_DESC_SIZE(rfs->old_fs->super);
334 	}
335 
336 	ext2fs_free_mem(&rfs->new_fs->group_desc);
337 	rfs->new_fs->group_desc = new_group_desc;
338 
339 	for (i = 0; i < rfs->old_fs->group_desc_count; i++)
340 		ext2fs_group_desc_csum_set(rfs->new_fs, i);
341 
342 	adjust_reserved_gdt_blocks(rfs->old_fs, rfs->new_fs);
343 
344 	return 0;
345 }
346 
347 /* Move bitmaps/inode tables out of the way. */
move_bg_metadata(ext2_resize_t rfs)348 static errcode_t move_bg_metadata(ext2_resize_t rfs)
349 {
350 	dgrp_t i;
351 	blk64_t b, c, d, old_desc_blocks, new_desc_blocks, j;
352 	ext2fs_block_bitmap old_map, new_map;
353 	int old, new;
354 	errcode_t retval;
355 	int cluster_ratio;
356 
357 	if (!(rfs->flags & (RESIZE_DISABLE_64BIT | RESIZE_ENABLE_64BIT)))
358 		return 0;
359 
360 	retval = ext2fs_allocate_block_bitmap(rfs->old_fs, "oldfs", &old_map);
361 	if (retval)
362 		return retval;
363 
364 	retval = ext2fs_allocate_block_bitmap(rfs->new_fs, "newfs", &new_map);
365 	if (retval)
366 		goto out;
367 
368 	if (ext2fs_has_feature_meta_bg(rfs->old_fs->super)) {
369 		old_desc_blocks = rfs->old_fs->super->s_first_meta_bg;
370 		new_desc_blocks = rfs->new_fs->super->s_first_meta_bg;
371 	} else {
372 		old_desc_blocks = rfs->old_fs->desc_blocks +
373 				rfs->old_fs->super->s_reserved_gdt_blocks;
374 		new_desc_blocks = rfs->new_fs->desc_blocks +
375 				rfs->new_fs->super->s_reserved_gdt_blocks;
376 	}
377 
378 	/* Construct bitmaps of super/descriptor blocks in old and new fs */
379 	for (i = 0; i < rfs->old_fs->group_desc_count; i++) {
380 		retval = ext2fs_super_and_bgd_loc2(rfs->old_fs, i, &b, &c, &d,
381 						   NULL);
382 		if (retval)
383 			goto out;
384 		if (b)
385 			ext2fs_mark_block_bitmap2(old_map, b);
386 		for (j = 0; c != 0 && j < old_desc_blocks; j++)
387 			ext2fs_mark_block_bitmap2(old_map, c + j);
388 		if (d)
389 			ext2fs_mark_block_bitmap2(old_map, d);
390 
391 		retval = ext2fs_super_and_bgd_loc2(rfs->new_fs, i, &b, &c, &d,
392 						   NULL);
393 		if (retval)
394 			goto out;
395 		if (b)
396 			ext2fs_mark_block_bitmap2(new_map, b);
397 		for (j = 0; c != 0 && j < new_desc_blocks; j++)
398 			ext2fs_mark_block_bitmap2(new_map, c + j);
399 		if (d)
400 			ext2fs_mark_block_bitmap2(new_map, d);
401 	}
402 
403 	cluster_ratio = EXT2FS_CLUSTER_RATIO(rfs->new_fs);
404 
405 	/* Find changes in block allocations for bg metadata */
406 	for (b = EXT2FS_B2C(rfs->old_fs,
407 			    rfs->old_fs->super->s_first_data_block);
408 	     b < ext2fs_blocks_count(rfs->new_fs->super);
409 	     b += cluster_ratio) {
410 		old = ext2fs_test_block_bitmap2(old_map, b);
411 		new = ext2fs_test_block_bitmap2(new_map, b);
412 
413 		if (old && !new) {
414 			/* mark old_map, unmark new_map */
415 			if (cluster_ratio == 1)
416 				ext2fs_unmark_block_bitmap2(
417 						rfs->new_fs->block_map, b);
418 		} else if (!old && new)
419 			; /* unmark old_map, mark new_map */
420 		else {
421 			ext2fs_unmark_block_bitmap2(old_map, b);
422 			ext2fs_unmark_block_bitmap2(new_map, b);
423 		}
424 	}
425 
426 	/*
427 	 * new_map now shows blocks that have been newly allocated.
428 	 * old_map now shows blocks that have been newly freed.
429 	 */
430 
431 	/*
432 	 * Move any conflicting bitmaps and inode tables.  Ensure that we
433 	 * don't try to free clusters associated with bitmaps or tables.
434 	 */
435 	for (i = 0; i < rfs->old_fs->group_desc_count; i++) {
436 		b = ext2fs_block_bitmap_loc(rfs->new_fs, i);
437 		if (ext2fs_test_block_bitmap2(new_map, b))
438 			ext2fs_block_bitmap_loc_set(rfs->new_fs, i, 0);
439 		else if (ext2fs_test_block_bitmap2(old_map, b))
440 			ext2fs_unmark_block_bitmap2(old_map, b);
441 
442 		b = ext2fs_inode_bitmap_loc(rfs->new_fs, i);
443 		if (ext2fs_test_block_bitmap2(new_map, b))
444 			ext2fs_inode_bitmap_loc_set(rfs->new_fs, i, 0);
445 		else if (ext2fs_test_block_bitmap2(old_map, b))
446 			ext2fs_unmark_block_bitmap2(old_map, b);
447 
448 		c = ext2fs_inode_table_loc(rfs->new_fs, i);
449 		for (b = 0;
450 		     b < rfs->new_fs->inode_blocks_per_group;
451 		     b++) {
452 			if (ext2fs_test_block_bitmap2(new_map, b + c))
453 				ext2fs_inode_table_loc_set(rfs->new_fs, i, 0);
454 			else if (ext2fs_test_block_bitmap2(old_map, b + c))
455 				ext2fs_unmark_block_bitmap2(old_map, b + c);
456 		}
457 	}
458 
459 	/* Free unused clusters */
460 	for (b = 0;
461 	     cluster_ratio > 1 && b < ext2fs_blocks_count(rfs->new_fs->super);
462 	     b += cluster_ratio)
463 		if (ext2fs_test_block_bitmap2(old_map, b))
464 			ext2fs_unmark_block_bitmap2(rfs->new_fs->block_map, b);
465 out:
466 	if (old_map)
467 		ext2fs_free_block_bitmap(old_map);
468 	if (new_map)
469 		ext2fs_free_block_bitmap(new_map);
470 	return retval;
471 }
472 
473 /* Zero out the high bits of extent fields */
zero_high_bits_in_extents(ext2_filsys fs,ext2_ino_t ino,struct ext2_inode * inode)474 static errcode_t zero_high_bits_in_extents(ext2_filsys fs, ext2_ino_t ino,
475 				 struct ext2_inode *inode)
476 {
477 	ext2_extent_handle_t	handle;
478 	struct ext2fs_extent	extent;
479 	int			op = EXT2_EXTENT_ROOT;
480 	errcode_t		errcode;
481 
482 	if (!(inode->i_flags & EXT4_EXTENTS_FL))
483 		return 0;
484 
485 	errcode = ext2fs_extent_open(fs, ino, &handle);
486 	if (errcode)
487 		return errcode;
488 
489 	while (1) {
490 		errcode = ext2fs_extent_get(handle, op, &extent);
491 		if (errcode)
492 			break;
493 
494 		op = EXT2_EXTENT_NEXT_SIB;
495 
496 		if (extent.e_pblk > (1ULL << 32)) {
497 			extent.e_pblk &= (1ULL << 32) - 1;
498 			errcode = ext2fs_extent_replace(handle, 0, &extent);
499 			if (errcode)
500 				break;
501 		}
502 	}
503 
504 	/* Ok if we run off the end */
505 	if (errcode == EXT2_ET_EXTENT_NO_NEXT)
506 		errcode = 0;
507 	ext2fs_extent_free(handle);
508 	return errcode;
509 }
510 
511 /* Zero out the high bits of inodes. */
zero_high_bits_in_inodes(ext2_resize_t rfs)512 static errcode_t zero_high_bits_in_inodes(ext2_resize_t rfs)
513 {
514 	ext2_filsys	fs = rfs->old_fs;
515 	int length = EXT2_INODE_SIZE(fs->super);
516 	struct ext2_inode *inode = NULL;
517 	ext2_inode_scan	scan = NULL;
518 	errcode_t	retval;
519 	ext2_ino_t	ino;
520 
521 	if (!(rfs->flags & (RESIZE_DISABLE_64BIT | RESIZE_ENABLE_64BIT)))
522 		return 0;
523 
524 	if (fs->super->s_creator_os == EXT2_OS_HURD)
525 		return 0;
526 
527 	retval = ext2fs_open_inode_scan(fs, 0, &scan);
528 	if (retval)
529 		return retval;
530 
531 	retval = ext2fs_get_mem(length, &inode);
532 	if (retval)
533 		goto out;
534 
535 	do {
536 		retval = ext2fs_get_next_inode_full(scan, &ino, inode, length);
537 		if (retval)
538 			goto out;
539 		if (!ino)
540 			break;
541 		if (!ext2fs_test_inode_bitmap2(fs->inode_map, ino))
542 			continue;
543 
544 		/*
545 		 * Here's how we deal with high block number fields:
546 		 *
547 		 *  - i_size_high has been been written out with i_size_lo
548 		 *    since the ext2 days, so no conversion is needed.
549 		 *
550 		 *  - i_blocks_hi is guarded by both the huge_file feature and
551 		 *    inode flags and has always been written out with
552 		 *    i_blocks_lo if the feature is set.  The field is only
553 		 *    ever read if both feature and inode flag are set, so
554 		 *    we don't need to zero it now.
555 		 *
556 		 *  - i_file_acl_high can be uninitialized, so zero it if
557 		 *    it isn't already.
558 		 */
559 		if (inode->osd2.linux2.l_i_file_acl_high) {
560 			inode->osd2.linux2.l_i_file_acl_high = 0;
561 			retval = ext2fs_write_inode_full(fs, ino, inode,
562 							 length);
563 			if (retval)
564 				goto out;
565 		}
566 
567 		retval = zero_high_bits_in_extents(fs, ino, inode);
568 		if (retval)
569 			goto out;
570 	} while (ino);
571 
572 out:
573 	if (inode)
574 		ext2fs_free_mem(&inode);
575 	if (scan)
576 		ext2fs_close_inode_scan(scan);
577 	return retval;
578 }
579 
580 /*
581  * Clean up the bitmaps for uninitialized bitmaps
582  */
fix_uninit_block_bitmaps(ext2_filsys fs)583 static void fix_uninit_block_bitmaps(ext2_filsys fs)
584 {
585 	blk64_t		blk, lblk;
586 	dgrp_t		g;
587 	unsigned int	i;
588 
589 	if (!ext2fs_has_group_desc_csum(fs))
590 		return;
591 
592 	for (g=0; g < fs->group_desc_count; g++) {
593 		if (!(ext2fs_bg_flags_test(fs, g, EXT2_BG_BLOCK_UNINIT)))
594 			continue;
595 
596 		blk = ext2fs_group_first_block2(fs, g);
597 		lblk = ext2fs_group_last_block2(fs, g);
598 		ext2fs_unmark_block_bitmap_range2(fs->block_map, blk,
599 						  lblk - blk + 1);
600 
601 		ext2fs_reserve_super_and_bgd(fs, g, fs->block_map);
602 		ext2fs_mark_block_bitmap2(fs->block_map,
603 					  ext2fs_block_bitmap_loc(fs, g));
604 		ext2fs_mark_block_bitmap2(fs->block_map,
605 					  ext2fs_inode_bitmap_loc(fs, g));
606 		for (i = 0, blk = ext2fs_inode_table_loc(fs, g);
607 		     i < fs->inode_blocks_per_group;
608 		     i++, blk++)
609 			ext2fs_mark_block_bitmap2(fs->block_map, blk);
610 	}
611 }
612 
613 /* --------------------------------------------------------------------
614  *
615  * Resize processing, phase 1.
616  *
617  * In this phase we adjust the in-memory superblock information, and
618  * initialize any new parts of the inode table.  The new parts of the
619  * inode table are created in virgin disk space, so we can abort here
620  * without any side effects.
621  * --------------------------------------------------------------------
622  */
623 
624 /*
625  * If the group descriptor's bitmap and inode table blocks are valid,
626  * release them in the new filesystem data structure, and mark them as
627  * reserved so the old inode table blocks don't get overwritten.
628  */
free_gdp_blocks(ext2_filsys fs,ext2fs_block_bitmap reserve_blocks,ext2_filsys old_fs,dgrp_t group)629 static errcode_t free_gdp_blocks(ext2_filsys fs,
630 				 ext2fs_block_bitmap reserve_blocks,
631 				 ext2_filsys old_fs,
632 				 dgrp_t group)
633 {
634 	blk64_t		blk;
635 	unsigned int	j;
636 	dgrp_t		i;
637 	ext2fs_block_bitmap bg_map = NULL;
638 	errcode_t	retval = 0;
639 	dgrp_t		count = old_fs->group_desc_count - fs->group_desc_count;
640 
641 	/* If bigalloc, don't free metadata living in the same cluster */
642 	if (EXT2FS_CLUSTER_RATIO(fs) > 1) {
643 		retval = ext2fs_allocate_block_bitmap(fs, "bgdata", &bg_map);
644 		if (retval)
645 			goto out;
646 
647 		retval = mark_table_blocks(fs, bg_map);
648 		if (retval)
649 			goto out;
650 	}
651 
652 	for (i = group; i < group + count; i++) {
653 		blk = ext2fs_block_bitmap_loc(old_fs, i);
654 		if (blk &&
655 		    (blk < ext2fs_blocks_count(fs->super)) &&
656 		    !(bg_map && ext2fs_test_block_bitmap2(bg_map, blk))) {
657 			ext2fs_block_alloc_stats2(fs, blk, -1);
658 			ext2fs_mark_block_bitmap2(reserve_blocks, blk);
659 		}
660 
661 		blk = ext2fs_inode_bitmap_loc(old_fs, i);
662 		if (blk &&
663 		    (blk < ext2fs_blocks_count(fs->super)) &&
664 		    !(bg_map && ext2fs_test_block_bitmap2(bg_map, blk))) {
665 			ext2fs_block_alloc_stats2(fs, blk, -1);
666 			ext2fs_mark_block_bitmap2(reserve_blocks, blk);
667 		}
668 
669 		blk = ext2fs_inode_table_loc(old_fs, i);
670 		for (j = 0;
671 		     j < fs->inode_blocks_per_group; j++, blk++) {
672 			if (blk >= ext2fs_blocks_count(fs->super) ||
673 			    (bg_map && ext2fs_test_block_bitmap2(bg_map, blk)))
674 				continue;
675 			ext2fs_block_alloc_stats2(fs, blk, -1);
676 			ext2fs_mark_block_bitmap2(reserve_blocks, blk);
677 		}
678 	}
679 
680 out:
681 	if (bg_map)
682 		ext2fs_free_block_bitmap(bg_map);
683 	return retval;
684 }
685 
686 /*
687  * This routine is shared by the online and offline resize routines.
688  * All of the information which is adjusted in memory is done here.
689  */
adjust_fs_info(ext2_filsys fs,ext2_filsys old_fs,ext2fs_block_bitmap reserve_blocks,blk64_t new_size)690 errcode_t adjust_fs_info(ext2_filsys fs, ext2_filsys old_fs,
691 			 ext2fs_block_bitmap reserve_blocks, blk64_t new_size)
692 {
693 	errcode_t	retval;
694 	blk64_t		overhead = 0;
695 	blk64_t		rem;
696 	blk64_t		blk, group_block;
697 	blk64_t		real_end;
698 	blk64_t		old_numblocks, numblocks, adjblocks;
699 	unsigned long	i, j, old_desc_blocks;
700 	unsigned int	meta_bg, meta_bg_size;
701 	int		has_super, csum_flag, has_bg;
702 	unsigned long long new_inodes;	/* u64 to check for overflow */
703 	double		percent;
704 
705 	ext2fs_blocks_count_set(fs->super, new_size);
706 	fs->super->s_overhead_clusters = 0;
707 
708 retry:
709 	fs->group_desc_count = ext2fs_div64_ceil(ext2fs_blocks_count(fs->super) -
710 				       fs->super->s_first_data_block,
711 				       EXT2_BLOCKS_PER_GROUP(fs->super));
712 	if (fs->group_desc_count == 0)
713 		return EXT2_ET_TOOSMALL;
714 	fs->desc_blocks = ext2fs_div_ceil(fs->group_desc_count,
715 					  EXT2_DESC_PER_BLOCK(fs->super));
716 
717 	/*
718 	 * Overhead is the number of bookkeeping blocks per group.  It
719 	 * includes the superblock backup, the group descriptor
720 	 * backups, the inode bitmap, the block bitmap, and the inode
721 	 * table.
722 	 */
723 	overhead = (int) (2 + fs->inode_blocks_per_group);
724 
725 	has_bg = 0;
726 	if (ext2fs_has_feature_sparse_super2(fs->super)) {
727 		/*
728 		 * We have to do this manually since
729 		 * super->s_backup_bgs hasn't been set up yet.
730 		 */
731 		if (fs->group_desc_count == 2)
732 			has_bg = fs->super->s_backup_bgs[0] != 0;
733 		else
734 			has_bg = fs->super->s_backup_bgs[1] != 0;
735 	} else
736 		has_bg = ext2fs_bg_has_super(fs, fs->group_desc_count - 1);
737 	if (has_bg)
738 		overhead += 1 + fs->desc_blocks +
739 			fs->super->s_reserved_gdt_blocks;
740 
741 	/*
742 	 * See if the last group is big enough to support the
743 	 * necessary data structures.  If not, we need to get rid of
744 	 * it.
745 	 */
746 	rem = (ext2fs_blocks_count(fs->super) - fs->super->s_first_data_block) %
747 		fs->super->s_blocks_per_group;
748 	if ((fs->group_desc_count == 1) && rem && (rem < overhead))
749 		return EXT2_ET_TOOSMALL;
750 	if ((fs->group_desc_count > 1) && rem && (rem < overhead+50)) {
751 		ext2fs_blocks_count_set(fs->super,
752 					ext2fs_blocks_count(fs->super) - rem);
753 		goto retry;
754 	}
755 	/*
756 	 * Adjust the number of inodes
757 	 */
758 	new_inodes =(unsigned long long) fs->super->s_inodes_per_group * fs->group_desc_count;
759 	if (new_inodes > ~0U) {
760 		new_inodes = (unsigned long long) fs->super->s_inodes_per_group * (fs->group_desc_count - 1);
761 		if (new_inodes <= ~0U) {
762 			unsigned long long new_blocks =
763 		((unsigned long long) fs->super->s_blocks_per_group *
764 		 (fs->group_desc_count - 1)) + fs->super->s_first_data_block;
765 
766 			ext2fs_blocks_count_set(fs->super, new_blocks);
767 			goto retry;
768 		}
769 		fprintf(stderr, _("inodes (%llu) must be less than %u\n"),
770 			(unsigned long long) new_inodes, ~0U);
771 		return EXT2_ET_TOO_MANY_INODES;
772 	}
773 	fs->super->s_inodes_count = fs->super->s_inodes_per_group *
774 		fs->group_desc_count;
775 
776 	/*
777 	 * Adjust the number of free blocks
778 	 */
779 	blk = ext2fs_blocks_count(old_fs->super);
780 	if (blk > ext2fs_blocks_count(fs->super))
781 		ext2fs_free_blocks_count_set(fs->super,
782 			ext2fs_free_blocks_count(fs->super) -
783 			(blk - ext2fs_blocks_count(fs->super)));
784 	else
785 		ext2fs_free_blocks_count_set(fs->super,
786 			ext2fs_free_blocks_count(fs->super) +
787 			(ext2fs_blocks_count(fs->super) - blk));
788 
789 	/*
790 	 * Adjust the number of reserved blocks
791 	 */
792 	percent = (ext2fs_r_blocks_count(old_fs->super) * 100.0) /
793 		ext2fs_blocks_count(old_fs->super);
794 	ext2fs_r_blocks_count_set(fs->super,
795 				  (percent * ext2fs_blocks_count(fs->super) /
796 				   100.0));
797 
798 	/*
799 	 * Adjust the bitmaps for size
800 	 */
801 	retval = ext2fs_resize_inode_bitmap2(fs->super->s_inodes_count,
802 					    fs->super->s_inodes_count,
803 					    fs->inode_map);
804 	if (retval) goto errout;
805 
806 	real_end = EXT2_GROUPS_TO_BLOCKS(fs->super, fs->group_desc_count) - 1 +
807 		fs->super->s_first_data_block;
808 	retval = ext2fs_resize_block_bitmap2(new_size - 1,
809 					     real_end, fs->block_map);
810 	if (retval) goto errout;
811 
812 	/*
813 	 * If we are growing the file system, also grow the size of
814 	 * the reserve_blocks bitmap
815 	 */
816 	if (reserve_blocks && new_size > ext2fs_blocks_count(old_fs->super)) {
817 		retval = ext2fs_resize_block_bitmap2(new_size - 1,
818 						     real_end, reserve_blocks);
819 		if (retval) goto errout;
820 	}
821 
822 	/*
823 	 * Reallocate the group descriptors as necessary.
824 	 */
825 	if (EXT2_DESC_SIZE(old_fs->super) == EXT2_DESC_SIZE(fs->super) &&
826 	    old_fs->desc_blocks != fs->desc_blocks) {
827 		retval = ext2fs_resize_mem(old_fs->desc_blocks *
828 					   fs->blocksize,
829 					   fs->desc_blocks * fs->blocksize,
830 					   &fs->group_desc);
831 		if (retval)
832 			goto errout;
833 		if (fs->desc_blocks > old_fs->desc_blocks)
834 			memset((char *) fs->group_desc +
835 			       (old_fs->desc_blocks * fs->blocksize), 0,
836 			       (fs->desc_blocks - old_fs->desc_blocks) *
837 			       fs->blocksize);
838 	}
839 
840 	/*
841 	 * If the resize_inode feature is set, and we are changing the
842 	 * number of descriptor blocks, then adjust
843 	 * s_reserved_gdt_blocks if possible to avoid needing to move
844 	 * the inode table either now or in the future.
845 	 *
846 	 * Note: If we're converting to 64bit mode, we did this earlier.
847 	 */
848 	if (EXT2_DESC_SIZE(old_fs->super) == EXT2_DESC_SIZE(fs->super))
849 		adjust_reserved_gdt_blocks(old_fs, fs);
850 
851 	if (ext2fs_has_feature_meta_bg(fs->super) &&
852 	    (fs->super->s_first_meta_bg > fs->desc_blocks)) {
853 		ext2fs_clear_feature_meta_bg(fs->super);
854 		fs->super->s_first_meta_bg = 0;
855 	}
856 
857 	/*
858 	 * Update the location of the backup superblocks if the
859 	 * sparse_super2 feature is enabled.
860 	 */
861 	if (ext2fs_has_feature_sparse_super2(fs->super)) {
862 		dgrp_t last_bg = fs->group_desc_count - 1;
863 		dgrp_t old_last_bg = old_fs->group_desc_count - 1;
864 
865 		if (last_bg > old_last_bg) {
866 			if (old_fs->group_desc_count == 1)
867 				fs->super->s_backup_bgs[0] = 1;
868 			if ((old_fs->group_desc_count < 3 &&
869 			     fs->group_desc_count > 2) ||
870 			    fs->super->s_backup_bgs[1])
871 				fs->super->s_backup_bgs[1] = last_bg;
872 		} else if (last_bg < old_last_bg) {
873 			if (fs->super->s_backup_bgs[0] > last_bg)
874 				fs->super->s_backup_bgs[0] = 0;
875 			if (fs->super->s_backup_bgs[1] > last_bg)
876 				fs->super->s_backup_bgs[1] = 0;
877 			if (last_bg > 1 &&
878 			    old_fs->super->s_backup_bgs[1] == old_last_bg)
879 				fs->super->s_backup_bgs[1] = last_bg;
880 		}
881 	}
882 
883 	/*
884 	 * If we are shrinking the number of block groups, we're done
885 	 * and can exit now.
886 	 */
887 	if (old_fs->group_desc_count > fs->group_desc_count) {
888 		/*
889 		 * Check the block groups that we are chopping off
890 		 * and free any blocks associated with their metadata
891 		 */
892 		retval = free_gdp_blocks(fs, reserve_blocks, old_fs,
893 					 fs->group_desc_count);
894 		goto errout;
895 	}
896 
897 	/*
898 	 * Fix the count of the last (old) block group
899 	 */
900 	old_numblocks = (ext2fs_blocks_count(old_fs->super) -
901 			 old_fs->super->s_first_data_block) %
902 				 old_fs->super->s_blocks_per_group;
903 	if (!old_numblocks)
904 		old_numblocks = old_fs->super->s_blocks_per_group;
905 	if (old_fs->group_desc_count == fs->group_desc_count) {
906 		numblocks = (ext2fs_blocks_count(fs->super) -
907 			     fs->super->s_first_data_block) %
908 			fs->super->s_blocks_per_group;
909 		if (!numblocks)
910 			numblocks = fs->super->s_blocks_per_group;
911 	} else
912 		numblocks = fs->super->s_blocks_per_group;
913 	i = old_fs->group_desc_count - 1;
914 	ext2fs_bg_free_blocks_count_set(fs, i, ext2fs_bg_free_blocks_count(fs, i) + (numblocks - old_numblocks));
915 	ext2fs_group_desc_csum_set(fs, i);
916 
917 	/*
918 	 * If the number of block groups is staying the same, we're
919 	 * done and can exit now.  (If the number block groups is
920 	 * shrinking, we had exited earlier.)
921 	 */
922 	if (old_fs->group_desc_count >= fs->group_desc_count) {
923 		retval = 0;
924 		goto errout;
925 	}
926 
927 	/*
928 	 * Initialize the new block group descriptors
929 	 */
930 	group_block = ext2fs_group_first_block2(fs,
931 						old_fs->group_desc_count);
932 	csum_flag = ext2fs_has_group_desc_csum(fs);
933 	if (getenv("RESIZE2FS_FORCE_LAZY_ITABLE_INIT") ||
934 	    (!getenv("RESIZE2FS_FORCE_ITABLE_INIT") &&
935 	     access("/sys/fs/ext4/features/lazy_itable_init", F_OK) == 0))
936 		lazy_itable_init = 1;
937 	if (ext2fs_has_feature_meta_bg(fs->super))
938 		old_desc_blocks = fs->super->s_first_meta_bg;
939 	else
940 		old_desc_blocks = fs->desc_blocks +
941 			fs->super->s_reserved_gdt_blocks;
942 
943 	/*
944 	 * If we changed the number of block_group descriptor blocks,
945 	 * we need to make sure they are all marked as reserved in the
946 	 * filesystem's block allocation map.
947 	 */
948 	for (i = 0; i < old_fs->group_desc_count; i++)
949 		ext2fs_reserve_super_and_bgd(fs, i, fs->block_map);
950 
951 	for (i = old_fs->group_desc_count;
952 	     i < fs->group_desc_count; i++) {
953 		memset(ext2fs_group_desc(fs, fs->group_desc, i), 0,
954 		       sizeof(struct ext2_group_desc));
955 		adjblocks = 0;
956 
957 		ext2fs_bg_flags_zap(fs, i);
958 		if (csum_flag) {
959 			ext2fs_bg_flags_set(fs, i, EXT2_BG_INODE_UNINIT);
960 			if (!lazy_itable_init)
961 				ext2fs_bg_flags_set(fs, i,
962 						    EXT2_BG_INODE_ZEROED);
963 			ext2fs_bg_itable_unused_set(fs, i,
964 					fs->super->s_inodes_per_group);
965 		}
966 
967 		numblocks = ext2fs_group_blocks_count(fs, i);
968 		if ((i < fs->group_desc_count - 1) && csum_flag)
969 			ext2fs_bg_flags_set(fs, i, EXT2_BG_BLOCK_UNINIT);
970 
971 		has_super = ext2fs_bg_has_super(fs, i);
972 		if (has_super) {
973 			ext2fs_block_alloc_stats2(fs, group_block, +1);
974 			adjblocks++;
975 		}
976 		meta_bg_size = EXT2_DESC_PER_BLOCK(fs->super);
977 		meta_bg = i / meta_bg_size;
978 		if (!ext2fs_has_feature_meta_bg(fs->super) ||
979 		    (meta_bg < fs->super->s_first_meta_bg)) {
980 			if (has_super) {
981 				for (j=0; j < old_desc_blocks; j++)
982 					ext2fs_block_alloc_stats2(fs,
983 						 group_block + 1 + j, +1);
984 				adjblocks += old_desc_blocks;
985 			}
986 		} else {
987 			if (has_super)
988 				has_super = 1;
989 			if (((i % meta_bg_size) == 0) ||
990 			    ((i % meta_bg_size) == 1) ||
991 			    ((i % meta_bg_size) == (meta_bg_size-1)))
992 				ext2fs_block_alloc_stats2(fs,
993 						 group_block + has_super, +1);
994 		}
995 
996 		adjblocks += 2 + fs->inode_blocks_per_group;
997 
998 		numblocks -= adjblocks;
999 		ext2fs_free_blocks_count_set(fs->super,
1000 			     ext2fs_free_blocks_count(fs->super) - adjblocks);
1001 		fs->super->s_free_inodes_count +=
1002 			fs->super->s_inodes_per_group;
1003 		ext2fs_bg_free_blocks_count_set(fs, i, numblocks);
1004 		ext2fs_bg_free_inodes_count_set(fs, i,
1005 						fs->super->s_inodes_per_group);
1006 		ext2fs_bg_used_dirs_count_set(fs, i, 0);
1007 		ext2fs_group_desc_csum_set(fs, i);
1008 
1009 		retval = ext2fs_allocate_group_table(fs, i, 0);
1010 		if (retval) goto errout;
1011 
1012 		group_block += fs->super->s_blocks_per_group;
1013 	}
1014 	retval = 0;
1015 
1016 	/*
1017 	 * Mark all of the metadata blocks as reserved so they won't
1018 	 * get allocated by the call to ext2fs_allocate_group_table()
1019 	 * in blocks_to_move(), where we allocate new blocks to
1020 	 * replace those allocation bitmap and inode table blocks
1021 	 * which have to get relocated to make space for an increased
1022 	 * number of the block group descriptors.
1023 	 */
1024 	if (reserve_blocks)
1025 		mark_table_blocks(fs, reserve_blocks);
1026 
1027 errout:
1028 	return (retval);
1029 }
1030 
1031 /*
1032  * Replicate the first part of adjust_fs_info to determine what the
1033  * new size of the file system should be.  This allows resize2fs to
1034  * exit early if we aren't going to make any changes to the file
1035  * system.
1036  */
adjust_new_size(ext2_filsys fs,blk64_t * sizep)1037 void adjust_new_size(ext2_filsys fs, blk64_t *sizep)
1038 {
1039 	blk64_t		size, rem, overhead = 0;
1040 	unsigned long	desc_blocks;
1041 	dgrp_t		group_desc_count;
1042 	int		has_bg;
1043 	unsigned long long new_inodes;	/* u64 to check for overflow */
1044 
1045 	size = *sizep;
1046 retry:
1047 	group_desc_count = ext2fs_div64_ceil(size -
1048 					     fs->super->s_first_data_block,
1049 					     EXT2_BLOCKS_PER_GROUP(fs->super));
1050 	if (group_desc_count == 0)
1051 		return;
1052 	desc_blocks = ext2fs_div_ceil(group_desc_count,
1053 				      EXT2_DESC_PER_BLOCK(fs->super));
1054 
1055 	/*
1056 	 * Overhead is the number of bookkeeping blocks per group.  It
1057 	 * includes the superblock backup, the group descriptor
1058 	 * backups, the inode bitmap, the block bitmap, and the inode
1059 	 * table.
1060 	 */
1061 	overhead = (int) (2 + fs->inode_blocks_per_group);
1062 
1063 	has_bg = 0;
1064 	if (ext2fs_has_feature_sparse_super2(fs->super)) {
1065 		/*
1066 		 * We have to do this manually since
1067 		 * super->s_backup_bgs hasn't been set up yet.
1068 		 */
1069 		if (group_desc_count == 2)
1070 			has_bg = fs->super->s_backup_bgs[0] != 0;
1071 		else
1072 			has_bg = fs->super->s_backup_bgs[1] != 0;
1073 	} else
1074 		has_bg = ext2fs_bg_has_super(fs, group_desc_count - 1);
1075 	if (has_bg)
1076 		overhead += 1 + desc_blocks +
1077 			fs->super->s_reserved_gdt_blocks;
1078 
1079 	/*
1080 	 * See if the last group is big enough to support the
1081 	 * necessary data structures.  If not, we need to get rid of
1082 	 * it.
1083 	 */
1084 	rem = (size - fs->super->s_first_data_block) %
1085 		fs->super->s_blocks_per_group;
1086 	if ((group_desc_count == 1) && rem && (rem < overhead))
1087 		return;
1088 	if ((group_desc_count > 1) && rem && (rem < overhead+50)) {
1089 		size -= rem;
1090 		goto retry;
1091 	}
1092 
1093 	/*
1094 	 * If we need to reduce the size by no more than a block
1095 	 * group to avoid overrunning the max inode limit, do it.
1096 	 */
1097 	new_inodes =(unsigned long long) fs->super->s_inodes_per_group * group_desc_count;
1098 	if (new_inodes > ~0U) {
1099 		new_inodes = (unsigned long long) fs->super->s_inodes_per_group * (group_desc_count - 1);
1100 		if (new_inodes > ~0U)
1101 			return;
1102 		size = ((unsigned long long) fs->super->s_blocks_per_group *
1103 			(group_desc_count - 1)) + fs->super->s_first_data_block;
1104 
1105 		goto retry;
1106 	}
1107 	*sizep = size;
1108 }
1109 
1110 /*
1111  * This routine adjusts the superblock and other data structures, both
1112  * in disk as well as in memory...
1113  */
adjust_superblock(ext2_resize_t rfs,blk64_t new_size)1114 static errcode_t adjust_superblock(ext2_resize_t rfs, blk64_t new_size)
1115 {
1116 	ext2_filsys	fs = rfs->new_fs;
1117 	int		adj = 0;
1118 	errcode_t	retval;
1119 	unsigned long	i;
1120 	unsigned long	max_group;
1121 
1122 	ext2fs_mark_super_dirty(fs);
1123 	ext2fs_mark_bb_dirty(fs);
1124 	ext2fs_mark_ib_dirty(fs);
1125 
1126 	retval = ext2fs_allocate_block_bitmap(fs, _("reserved blocks"),
1127 					      &rfs->reserve_blocks);
1128 	if (retval)
1129 		return retval;
1130 
1131 	retval = adjust_fs_info(fs, rfs->old_fs, rfs->reserve_blocks, new_size);
1132 	if (retval)
1133 		goto errout;
1134 
1135 	/*
1136 	 * Check to make sure there are enough inodes
1137 	 */
1138 	if ((rfs->old_fs->super->s_inodes_count -
1139 	     rfs->old_fs->super->s_free_inodes_count) >
1140 	    rfs->new_fs->super->s_inodes_count) {
1141 		retval = ENOSPC;
1142 		goto errout;
1143 	}
1144 
1145 	/*
1146 	 * If we are shrinking the number block groups, we're done and
1147 	 * can exit now.
1148 	 */
1149 	if (rfs->old_fs->group_desc_count > fs->group_desc_count) {
1150 		retval = 0;
1151 		goto errout;
1152 	}
1153 
1154 	/*
1155 	 * If the number of block groups is staying the same, we're
1156 	 * done and can exit now.  (If the number block groups is
1157 	 * shrinking, we had exited earlier.)
1158 	 */
1159 	if (rfs->old_fs->group_desc_count >= fs->group_desc_count) {
1160 		retval = 0;
1161 		goto errout;
1162 	}
1163 
1164 	/*
1165 	 * If we are using uninit_bg (aka GDT_CSUM) and the kernel
1166 	 * supports lazy inode initialization, we can skip
1167 	 * initializing the inode table.
1168 	 */
1169 	if (lazy_itable_init && ext2fs_has_group_desc_csum(fs)) {
1170 		retval = 0;
1171 		goto errout;
1172 	}
1173 
1174 	/*
1175 	 * Initialize the inode table
1176 	 */
1177 	retval = ext2fs_get_array(fs->blocksize, fs->inode_blocks_per_group,
1178 				&rfs->itable_buf);
1179 	if (retval)
1180 		goto errout;
1181 
1182 	memset(rfs->itable_buf, 0, fs->blocksize * fs->inode_blocks_per_group);
1183 	adj = rfs->old_fs->group_desc_count;
1184 	max_group = fs->group_desc_count - adj;
1185 	if (rfs->progress) {
1186 		retval = rfs->progress(rfs, E2_RSZ_EXTEND_ITABLE_PASS,
1187 				       0, max_group);
1188 		if (retval)
1189 			goto errout;
1190 	}
1191 	for (i = rfs->old_fs->group_desc_count;
1192 	     i < fs->group_desc_count; i++) {
1193 		/*
1194 		 * Write out the new inode table
1195 		 */
1196 		retval = ext2fs_zero_blocks2(fs, ext2fs_inode_table_loc(fs, i),
1197 					     fs->inode_blocks_per_group, NULL,
1198 					     NULL);
1199 		if (retval)
1200 			goto errout;
1201 
1202 		io_channel_flush(fs->io);
1203 		if (rfs->progress) {
1204 			retval = rfs->progress(rfs, E2_RSZ_EXTEND_ITABLE_PASS,
1205 					       i - adj + 1, max_group);
1206 			if (retval)
1207 				goto errout;
1208 		}
1209 	}
1210 	io_channel_flush(fs->io);
1211 	retval = 0;
1212 
1213 errout:
1214 	return retval;
1215 }
1216 
1217 /* --------------------------------------------------------------------
1218  *
1219  * Resize processing, phase 2.
1220  *
1221  * In this phase we adjust determine which blocks need to be moved, in
1222  * blocks_to_move().  We then copy the blocks to their ultimate new
1223  * destinations using block_mover().  Since we are copying blocks to
1224  * their new locations, again during this pass we can abort without
1225  * any problems.
1226  * --------------------------------------------------------------------
1227  */
1228 
1229 /*
1230  * This helper function creates a block bitmap with all of the
1231  * filesystem meta-data blocks.
1232  */
mark_table_blocks(ext2_filsys fs,ext2fs_block_bitmap bmap)1233 static errcode_t mark_table_blocks(ext2_filsys fs,
1234 				   ext2fs_block_bitmap bmap)
1235 {
1236 	dgrp_t			i;
1237 	blk64_t			blk;
1238 
1239 	for (i = 0; i < fs->group_desc_count; i++) {
1240 		ext2fs_reserve_super_and_bgd(fs, i, bmap);
1241 
1242 		/*
1243 		 * Mark the blocks used for the inode table
1244 		 */
1245 		blk = ext2fs_inode_table_loc(fs, i);
1246 		if (blk)
1247 			ext2fs_mark_block_bitmap_range2(bmap, blk,
1248 						fs->inode_blocks_per_group);
1249 
1250 		/*
1251 		 * Mark block used for the block bitmap
1252 		 */
1253 		blk = ext2fs_block_bitmap_loc(fs, i);
1254 		if (blk)
1255 			ext2fs_mark_block_bitmap2(bmap, blk);
1256 
1257 		/*
1258 		 * Mark block used for the inode bitmap
1259 		 */
1260 		blk = ext2fs_inode_bitmap_loc(fs, i);
1261 		if (blk)
1262 			ext2fs_mark_block_bitmap2(bmap, blk);
1263 	}
1264 	/* Reserve the MMP block */
1265 	if (ext2fs_has_feature_mmp(fs->super) &&
1266 	    fs->super->s_mmp_block > fs->super->s_first_data_block &&
1267 	    fs->super->s_mmp_block < ext2fs_blocks_count(fs->super))
1268 		ext2fs_mark_block_bitmap2(bmap, fs->super->s_mmp_block);
1269 	return 0;
1270 }
1271 
1272 /*
1273  * This function checks to see if a particular block (either a
1274  * superblock or a block group descriptor) overlaps with an inode or
1275  * block bitmap block, or with the inode table.
1276  */
mark_fs_metablock(ext2_resize_t rfs,ext2fs_block_bitmap meta_bmap,int group,blk64_t blk)1277 static void mark_fs_metablock(ext2_resize_t rfs,
1278 			      ext2fs_block_bitmap meta_bmap,
1279 			      int group, blk64_t blk)
1280 {
1281 	ext2_filsys fs = rfs->new_fs;
1282 
1283 	ext2fs_mark_block_bitmap2(rfs->reserve_blocks, blk);
1284 	ext2fs_block_alloc_stats2(fs, blk, +1);
1285 
1286 	/*
1287 	 * Check to see if we overlap with the inode or block bitmap,
1288 	 * or the inode tables.  If not, and the block is in use, then
1289 	 * mark it as a block to be moved.
1290 	 */
1291 	if (is_block_bm(fs, group, blk)) {
1292 		ext2fs_block_bitmap_loc_set(fs, group, 0);
1293 		rfs->needed_blocks++;
1294 		return;
1295 	}
1296 	if (is_inode_bm(fs, group, blk)) {
1297 		ext2fs_inode_bitmap_loc_set(fs, group, 0);
1298 		rfs->needed_blocks++;
1299 		return;
1300 	}
1301 	if (is_inode_tb(fs, group, blk)) {
1302 		ext2fs_inode_table_loc_set(fs, group, 0);
1303 		rfs->needed_blocks++;
1304 		return;
1305 	}
1306 	if (ext2fs_has_feature_flex_bg(fs->super)) {
1307 		dgrp_t i;
1308 
1309 		for (i = 0; i < rfs->old_fs->group_desc_count; i++) {
1310 			if (is_block_bm(fs, i, blk)) {
1311 				ext2fs_block_bitmap_loc_set(fs, i, 0);
1312 				rfs->needed_blocks++;
1313 				return;
1314 			}
1315 			if (is_inode_bm(fs, i, blk)) {
1316 				ext2fs_inode_bitmap_loc_set(fs, i, 0);
1317 				rfs->needed_blocks++;
1318 				return;
1319 			}
1320 			if (is_inode_tb(fs, i, blk)) {
1321 				ext2fs_inode_table_loc_set(fs, i, 0);
1322 				rfs->needed_blocks++;
1323 				return;
1324 			}
1325 		}
1326 	}
1327 
1328 	if (ext2fs_has_group_desc_csum(fs) &&
1329 	    (ext2fs_bg_flags_test(fs, group, EXT2_BG_BLOCK_UNINIT))) {
1330 		/*
1331 		 * If the block bitmap is uninitialized, which means
1332 		 * nothing other than standard metadata in use.
1333 		 */
1334 		return;
1335 	} else if (blk < ext2fs_blocks_count(rfs->old_fs->super) &&
1336 		   ext2fs_test_block_bitmap2(rfs->old_fs->block_map, blk) &&
1337 		   !ext2fs_test_block_bitmap2(meta_bmap, blk)) {
1338 		ext2fs_mark_block_bitmap2(rfs->move_blocks, blk);
1339 		rfs->needed_blocks++;
1340 	}
1341 }
1342 
1343 
1344 /*
1345  * This routine marks and unmarks reserved blocks in the new block
1346  * bitmap.  It also determines which blocks need to be moved and
1347  * places this information into the move_blocks bitmap.
1348  */
blocks_to_move(ext2_resize_t rfs)1349 static errcode_t blocks_to_move(ext2_resize_t rfs)
1350 {
1351 	unsigned int	j;
1352 	int		has_super;
1353 	dgrp_t		i, max_groups, g;
1354 	blk64_t		blk, group_blk;
1355 	blk64_t		old_blocks, new_blocks, group_end, cluster_freed;
1356 	blk64_t		new_size;
1357 	unsigned int	meta_bg, meta_bg_size;
1358 	errcode_t	retval;
1359 	ext2_filsys 	fs, old_fs;
1360 	ext2fs_block_bitmap	meta_bmap, new_meta_bmap = NULL;
1361 	int		flex_bg;
1362 
1363 	fs = rfs->new_fs;
1364 	old_fs = rfs->old_fs;
1365 	if (ext2fs_blocks_count(old_fs->super) > ext2fs_blocks_count(fs->super))
1366 		fs = rfs->old_fs;
1367 
1368 	retval = ext2fs_allocate_block_bitmap(fs, _("blocks to be moved"),
1369 					      &rfs->move_blocks);
1370 	if (retval)
1371 		return retval;
1372 
1373 	retval = ext2fs_allocate_block_bitmap(fs, _("meta-data blocks"),
1374 					      &meta_bmap);
1375 	if (retval)
1376 		return retval;
1377 
1378 	retval = mark_table_blocks(old_fs, meta_bmap);
1379 	if (retval)
1380 		return retval;
1381 
1382 	fs = rfs->new_fs;
1383 
1384 	/*
1385 	 * If we're shrinking the filesystem, we need to move any
1386 	 * group's metadata blocks (either allocation bitmaps or the
1387 	 * inode table) which are beyond the end of the new
1388 	 * filesystem.
1389 	 */
1390 	new_size = ext2fs_blocks_count(fs->super);
1391 	if (new_size < ext2fs_blocks_count(old_fs->super)) {
1392 		for (g = 0; g < fs->group_desc_count; g++) {
1393 			int realloc = 0;
1394 			/*
1395 			 * ext2fs_allocate_group_table will re-allocate any
1396 			 * metadata blocks whose location is set to zero.
1397 			 */
1398 			if (ext2fs_block_bitmap_loc(fs, g) >= new_size) {
1399 				ext2fs_block_bitmap_loc_set(fs, g, 0);
1400 				realloc = 1;
1401 			}
1402 			if (ext2fs_inode_bitmap_loc(fs, g) >= new_size) {
1403 				ext2fs_inode_bitmap_loc_set(fs, g, 0);
1404 				realloc = 1;
1405 			}
1406 			if ((ext2fs_inode_table_loc(fs, g) +
1407 			     fs->inode_blocks_per_group) > new_size) {
1408 				ext2fs_inode_table_loc_set(fs, g, 0);
1409 				realloc = 1;
1410 			}
1411 
1412 			if (realloc) {
1413 				retval = ext2fs_allocate_group_table(fs, g, 0);
1414 				if (retval)
1415 					return retval;
1416 			}
1417 		}
1418 	}
1419 
1420 	/*
1421 	 * If we're shrinking the filesystem, we need to move all of
1422 	 * the blocks that don't fit any more
1423 	 */
1424 	for (blk = ext2fs_blocks_count(fs->super);
1425 	     blk < ext2fs_blocks_count(old_fs->super); blk++) {
1426 		g = ext2fs_group_of_blk2(fs, blk);
1427 		if (ext2fs_has_group_desc_csum(fs) &&
1428 		    ext2fs_bg_flags_test(old_fs, g, EXT2_BG_BLOCK_UNINIT)) {
1429 			/*
1430 			 * The block bitmap is uninitialized, so skip
1431 			 * to the next block group.
1432 			 */
1433 			blk = ext2fs_group_first_block2(fs, g+1) - 1;
1434 			continue;
1435 		}
1436 		if (ext2fs_test_block_bitmap2(old_fs->block_map, blk) &&
1437 		    !ext2fs_test_block_bitmap2(meta_bmap, blk)) {
1438 			ext2fs_mark_block_bitmap2(rfs->move_blocks, blk);
1439 			rfs->needed_blocks++;
1440 		}
1441 		ext2fs_mark_block_bitmap2(rfs->reserve_blocks, blk);
1442 	}
1443 
1444 	if (ext2fs_has_feature_meta_bg(old_fs->super))
1445 		old_blocks = old_fs->super->s_first_meta_bg;
1446 	else
1447 		old_blocks = old_fs->desc_blocks +
1448 			old_fs->super->s_reserved_gdt_blocks;
1449 	if (ext2fs_has_feature_meta_bg(fs->super))
1450 		new_blocks = fs->super->s_first_meta_bg;
1451 	else
1452 		new_blocks = fs->desc_blocks + fs->super->s_reserved_gdt_blocks;
1453 
1454 	retval = reserve_sparse_super2_last_group(rfs, meta_bmap);
1455 	if (retval)
1456 		goto errout;
1457 
1458 	if (EXT2_DESC_SIZE(rfs->old_fs->super) ==
1459 	    EXT2_DESC_SIZE(rfs->new_fs->super) &&
1460 	    old_blocks == new_blocks) {
1461 		retval = 0;
1462 		goto errout;
1463 	}
1464 
1465 	max_groups = fs->group_desc_count;
1466 	if (max_groups > old_fs->group_desc_count)
1467 		max_groups = old_fs->group_desc_count;
1468 	group_blk = old_fs->super->s_first_data_block;
1469 	/*
1470 	 * If we're reducing the number of descriptor blocks, this
1471 	 * makes life easy.  :-)   We just have to mark some extra
1472 	 * blocks as free.
1473 	 */
1474 	if (old_blocks > new_blocks) {
1475 		if (EXT2FS_CLUSTER_RATIO(fs) > 1) {
1476 			retval = ext2fs_allocate_block_bitmap(fs,
1477 							_("new meta blocks"),
1478 							&new_meta_bmap);
1479 			if (retval)
1480 				goto errout;
1481 
1482 			retval = mark_table_blocks(fs, new_meta_bmap);
1483 			if (retval)
1484 				goto errout;
1485 		}
1486 
1487 		for (i = 0; i < max_groups; i++) {
1488 			if (!ext2fs_bg_has_super(old_fs, i)) {
1489 				group_blk += fs->super->s_blocks_per_group;
1490 				continue;
1491 			}
1492 			group_end = group_blk + 1 + old_blocks;
1493 			for (blk = group_blk + 1 + new_blocks;
1494 			     blk < group_end;) {
1495 				if (new_meta_bmap == NULL ||
1496 				    !ext2fs_test_block_bitmap2(new_meta_bmap,
1497 							       blk)) {
1498 					cluster_freed =
1499 						EXT2FS_CLUSTER_RATIO(fs) -
1500 						(blk &
1501 						 EXT2FS_CLUSTER_MASK(fs));
1502 					if (cluster_freed > group_end - blk)
1503 						cluster_freed = group_end - blk;
1504 					ext2fs_block_alloc_stats2(fs, blk, -1);
1505 					blk += EXT2FS_CLUSTER_RATIO(fs);
1506 					rfs->needed_blocks -= cluster_freed;
1507 					continue;
1508 				}
1509 				rfs->needed_blocks--;
1510 				blk++;
1511 			}
1512 			group_blk += fs->super->s_blocks_per_group;
1513 		}
1514 		retval = 0;
1515 		goto errout;
1516 	}
1517 	/*
1518 	 * If we're increasing the number of descriptor blocks, life
1519 	 * gets interesting....
1520 	 */
1521 	meta_bg_size = EXT2_DESC_PER_BLOCK(fs->super);
1522 	flex_bg = ext2fs_has_feature_flex_bg(fs->super);
1523 	/* first reserve all of the existing fs meta blocks */
1524 	for (i = 0; i < max_groups; i++) {
1525 		has_super = ext2fs_bg_has_super(fs, i);
1526 		if (has_super)
1527 			mark_fs_metablock(rfs, meta_bmap, i, group_blk);
1528 
1529 		meta_bg = i / meta_bg_size;
1530 		if (!ext2fs_has_feature_meta_bg(fs->super) ||
1531 		    (meta_bg < fs->super->s_first_meta_bg)) {
1532 			if (has_super) {
1533 				for (blk = group_blk+1;
1534 				     blk < group_blk + 1 + new_blocks; blk++)
1535 					mark_fs_metablock(rfs, meta_bmap,
1536 							  i, blk);
1537 			}
1538 		} else {
1539 			if (has_super)
1540 				has_super = 1;
1541 			if (((i % meta_bg_size) == 0) ||
1542 			    ((i % meta_bg_size) == 1) ||
1543 			    ((i % meta_bg_size) == (meta_bg_size-1)))
1544 				mark_fs_metablock(rfs, meta_bmap, i,
1545 						  group_blk + has_super);
1546 		}
1547 
1548 		/*
1549 		 * Reserve the existing meta blocks that we know
1550 		 * aren't to be moved.
1551 		 *
1552 		 * For flex_bg file systems, in order to avoid
1553 		 * overwriting fs metadata (especially inode table
1554 		 * blocks) belonging to a different block group when
1555 		 * we are relocating the inode tables, we need to
1556 		 * reserve all existing fs metadata blocks.
1557 		 */
1558 		if (ext2fs_block_bitmap_loc(fs, i))
1559 			ext2fs_mark_block_bitmap2(rfs->reserve_blocks,
1560 				 ext2fs_block_bitmap_loc(fs, i));
1561 		else if (flex_bg && i < old_fs->group_desc_count)
1562 			ext2fs_mark_block_bitmap2(rfs->reserve_blocks,
1563 				 ext2fs_block_bitmap_loc(old_fs, i));
1564 
1565 		if (ext2fs_inode_bitmap_loc(fs, i))
1566 			ext2fs_mark_block_bitmap2(rfs->reserve_blocks,
1567 				 ext2fs_inode_bitmap_loc(fs, i));
1568 		else if (flex_bg && i < old_fs->group_desc_count)
1569 			ext2fs_mark_block_bitmap2(rfs->reserve_blocks,
1570 				 ext2fs_inode_bitmap_loc(old_fs, i));
1571 
1572 		if (ext2fs_inode_table_loc(fs, i))
1573 			ext2fs_mark_block_bitmap_range2(rfs->reserve_blocks,
1574 					ext2fs_inode_table_loc(fs, i),
1575 					fs->inode_blocks_per_group);
1576 		else if (flex_bg && i < old_fs->group_desc_count)
1577 			ext2fs_mark_block_bitmap_range2(rfs->reserve_blocks,
1578 					ext2fs_inode_table_loc(old_fs, i),
1579 					old_fs->inode_blocks_per_group);
1580 
1581 		group_blk += rfs->new_fs->super->s_blocks_per_group;
1582 	}
1583 
1584 	/* Allocate the missing data structures */
1585 	for (i = 0; i < max_groups; i++) {
1586 		if (ext2fs_inode_table_loc(fs, i) &&
1587 		    ext2fs_inode_bitmap_loc(fs, i) &&
1588 		    ext2fs_block_bitmap_loc(fs, i))
1589 			continue;
1590 
1591 		retval = ext2fs_allocate_group_table(fs, i,
1592 						     rfs->reserve_blocks);
1593 		if (retval)
1594 			goto errout;
1595 
1596 		/*
1597 		 * For those structures that have changed, we need to
1598 		 * do bookkeeping.
1599 		 */
1600 		if (ext2fs_block_bitmap_loc(old_fs, i) !=
1601 		    (blk = ext2fs_block_bitmap_loc(fs, i))) {
1602 			ext2fs_block_alloc_stats2(fs, blk, +1);
1603 			if (blk < ext2fs_blocks_count(old_fs->super) &&
1604 			    ext2fs_test_block_bitmap2(old_fs->block_map, blk) &&
1605 			    !ext2fs_test_block_bitmap2(meta_bmap, blk))
1606 				ext2fs_mark_block_bitmap2(rfs->move_blocks,
1607 							 blk);
1608 		}
1609 		if (ext2fs_inode_bitmap_loc(old_fs, i) !=
1610 		    (blk = ext2fs_inode_bitmap_loc(fs, i))) {
1611 			ext2fs_block_alloc_stats2(fs, blk, +1);
1612 			if (blk < ext2fs_blocks_count(old_fs->super) &&
1613 			    ext2fs_test_block_bitmap2(old_fs->block_map, blk) &&
1614 			    !ext2fs_test_block_bitmap2(meta_bmap, blk))
1615 				ext2fs_mark_block_bitmap2(rfs->move_blocks,
1616 							 blk);
1617 		}
1618 
1619 		/*
1620 		 * The inode table, if we need to relocate it, is
1621 		 * handled specially.  We have to reserve the blocks
1622 		 * for both the old and the new inode table, since we
1623 		 * can't have the inode table be destroyed during the
1624 		 * block relocation phase.
1625 		 */
1626 		if (ext2fs_inode_table_loc(fs, i) == ext2fs_inode_table_loc(old_fs, i))
1627 			continue;	/* inode table not moved */
1628 
1629 		rfs->needed_blocks += fs->inode_blocks_per_group;
1630 
1631 		/*
1632 		 * Mark the new inode table as in use in the new block
1633 		 * allocation bitmap, and move any blocks that might
1634 		 * be necessary.
1635 		 */
1636 		for (blk = ext2fs_inode_table_loc(fs, i), j=0;
1637 		     j < fs->inode_blocks_per_group ; j++, blk++) {
1638 			ext2fs_block_alloc_stats2(fs, blk, +1);
1639 			if (blk < ext2fs_blocks_count(old_fs->super) &&
1640 			    ext2fs_test_block_bitmap2(old_fs->block_map, blk) &&
1641 			    !ext2fs_test_block_bitmap2(meta_bmap, blk))
1642 				ext2fs_mark_block_bitmap2(rfs->move_blocks,
1643 							 blk);
1644 		}
1645 
1646 		/*
1647 		 * Make sure the old inode table is reserved in the
1648 		 * block reservation bitmap.
1649 		 */
1650 		for (blk = ext2fs_inode_table_loc(rfs->old_fs, i), j=0;
1651 		     j < fs->inode_blocks_per_group ; j++, blk++)
1652 			ext2fs_mark_block_bitmap2(rfs->reserve_blocks, blk);
1653 	}
1654 	retval = 0;
1655 
1656 errout:
1657 	if (new_meta_bmap)
1658 		ext2fs_free_block_bitmap(new_meta_bmap);
1659 	if (meta_bmap)
1660 		ext2fs_free_block_bitmap(meta_bmap);
1661 
1662 	return retval;
1663 }
1664 
1665 /*
1666  * This helper function tries to allocate a new block.  We try to
1667  * avoid hitting the original group descriptor blocks at least at
1668  * first, since we want to make it possible to recover from a badly
1669  * aborted resize operation as much as possible.
1670  *
1671  * In the future, I may further modify this routine to balance out
1672  * where we get the new blocks across the various block groups.
1673  * Ideally we would allocate blocks that corresponded with the block
1674  * group of the containing inode, and keep contiguous blocks
1675  * together.  However, this very difficult to do efficiently, since we
1676  * don't have the necessary information up front.
1677  */
1678 
1679 #define AVOID_OLD	1
1680 #define DESPERATION	2
1681 
init_block_alloc(ext2_resize_t rfs)1682 static void init_block_alloc(ext2_resize_t rfs)
1683 {
1684 	rfs->alloc_state = AVOID_OLD;
1685 	rfs->new_blk = rfs->new_fs->super->s_first_data_block;
1686 #if 0
1687 	/* HACK for testing */
1688 	if (ext2fs_blocks_count(rfs->new_fs->super) >
1689 	    ext2fs_blocks_count(rfs->old_fs->super))
1690 		rfs->new_blk = ext2fs_blocks_count(rfs->old_fs->super);
1691 #endif
1692 }
1693 
get_new_block(ext2_resize_t rfs)1694 static blk64_t get_new_block(ext2_resize_t rfs)
1695 {
1696 	ext2_filsys	fs = rfs->new_fs;
1697 
1698 	while (1) {
1699 		if (rfs->new_blk >= ext2fs_blocks_count(fs->super)) {
1700 			if (rfs->alloc_state == DESPERATION)
1701 				return 0;
1702 
1703 #ifdef RESIZE2FS_DEBUG
1704 			if (rfs->flags & RESIZE_DEBUG_BMOVE)
1705 				printf("Going into desperation mode "
1706 				       "for block allocations\n");
1707 #endif
1708 			rfs->alloc_state = DESPERATION;
1709 			rfs->new_blk = fs->super->s_first_data_block;
1710 			continue;
1711 		}
1712 		if (ext2fs_test_block_bitmap2(fs->block_map, rfs->new_blk) ||
1713 		    ext2fs_test_block_bitmap2(rfs->reserve_blocks,
1714 					     rfs->new_blk) ||
1715 		    ((rfs->alloc_state == AVOID_OLD) &&
1716 		     (rfs->new_blk < ext2fs_blocks_count(rfs->old_fs->super)) &&
1717 		     ext2fs_test_block_bitmap2(rfs->old_fs->block_map,
1718 					      rfs->new_blk))) {
1719 			rfs->new_blk++;
1720 			continue;
1721 		}
1722 		return rfs->new_blk;
1723 	}
1724 }
1725 
resize2fs_get_alloc_block(ext2_filsys fs,blk64_t goal EXT2FS_ATTR ((unused)),blk64_t * ret)1726 static errcode_t resize2fs_get_alloc_block(ext2_filsys fs,
1727 					   blk64_t goal EXT2FS_ATTR((unused)),
1728 					   blk64_t *ret)
1729 {
1730 	ext2_resize_t rfs = (ext2_resize_t) fs->priv_data;
1731 	blk64_t blk;
1732 	int group;
1733 
1734 	blk = get_new_block(rfs);
1735 	if (!blk)
1736 		return ENOSPC;
1737 
1738 #ifdef RESIZE2FS_DEBUG
1739 	if (rfs->flags & 0xF)
1740 		printf("get_alloc_block allocating %llu\n",
1741 		       (unsigned long long) blk);
1742 #endif
1743 
1744 	ext2fs_mark_block_bitmap2(rfs->old_fs->block_map, blk);
1745 	ext2fs_mark_block_bitmap2(rfs->new_fs->block_map, blk);
1746 
1747 	group = ext2fs_group_of_blk2(rfs->old_fs, blk);
1748 	ext2fs_clear_block_uninit(rfs->old_fs, group);
1749 	group = ext2fs_group_of_blk2(rfs->new_fs, blk);
1750 	ext2fs_clear_block_uninit(rfs->new_fs, group);
1751 
1752 	*ret = (blk64_t) blk;
1753 	return 0;
1754 }
1755 
block_mover(ext2_resize_t rfs)1756 static errcode_t block_mover(ext2_resize_t rfs)
1757 {
1758 	blk64_t			blk, old_blk, new_blk;
1759 	ext2_filsys		fs = rfs->new_fs;
1760 	ext2_filsys		old_fs = rfs->old_fs;
1761 	errcode_t		retval;
1762 	__u64			c, size;
1763 	int			to_move, moved;
1764 	ext2_badblocks_list	badblock_list = 0;
1765 	int			bb_modified = 0;
1766 
1767 	fs->get_alloc_block = resize2fs_get_alloc_block;
1768 	old_fs->get_alloc_block = resize2fs_get_alloc_block;
1769 
1770 	retval = ext2fs_read_bb_inode(old_fs, &badblock_list);
1771 	if (retval)
1772 		return retval;
1773 
1774 	new_blk = fs->super->s_first_data_block;
1775 	if (!rfs->itable_buf) {
1776 		retval = ext2fs_get_array(fs->blocksize,
1777 					fs->inode_blocks_per_group,
1778 					&rfs->itable_buf);
1779 		if (retval)
1780 			goto errout;
1781 	}
1782 	retval = ext2fs_create_extent_table(&rfs->bmap, 0);
1783 	if (retval)
1784 		goto errout;
1785 
1786 	/*
1787 	 * The first step is to figure out where all of the blocks
1788 	 * will go.
1789 	 */
1790 	to_move = moved = 0;
1791 	init_block_alloc(rfs);
1792 	for (blk = B2C(old_fs->super->s_first_data_block);
1793 	     blk < ext2fs_blocks_count(old_fs->super);
1794 	     blk += EXT2FS_CLUSTER_RATIO(fs)) {
1795 		if (!ext2fs_test_block_bitmap2(old_fs->block_map, blk))
1796 			continue;
1797 		if (!ext2fs_test_block_bitmap2(rfs->move_blocks, blk))
1798 			continue;
1799 		if (ext2fs_badblocks_list_test(badblock_list, blk)) {
1800 			ext2fs_badblocks_list_del(badblock_list, blk);
1801 			bb_modified++;
1802 			continue;
1803 		}
1804 
1805 		new_blk = get_new_block(rfs);
1806 		if (!new_blk) {
1807 			retval = ENOSPC;
1808 			goto errout;
1809 		}
1810 		ext2fs_block_alloc_stats2(fs, new_blk, +1);
1811 		ext2fs_add_extent_entry(rfs->bmap, B2C(blk), B2C(new_blk));
1812 		to_move++;
1813 	}
1814 
1815 	if (to_move == 0) {
1816 		if (rfs->bmap) {
1817 			ext2fs_free_extent_table(rfs->bmap);
1818 			rfs->bmap = 0;
1819 		}
1820 		retval = 0;
1821 		goto errout;
1822 	}
1823 
1824 	/*
1825 	 * Step two is to actually move the blocks
1826 	 */
1827 	retval =  ext2fs_iterate_extent(rfs->bmap, 0, 0, 0);
1828 	if (retval) goto errout;
1829 
1830 	if (rfs->progress) {
1831 		retval = (rfs->progress)(rfs, E2_RSZ_BLOCK_RELOC_PASS,
1832 					 0, to_move);
1833 		if (retval)
1834 			goto errout;
1835 	}
1836 	while (1) {
1837 		retval = ext2fs_iterate_extent(rfs->bmap, &old_blk, &new_blk, &size);
1838 		if (retval) goto errout;
1839 		if (!size)
1840 			break;
1841 		old_blk = C2B(old_blk);
1842 		new_blk = C2B(new_blk);
1843 		size = C2B(size);
1844 #ifdef RESIZE2FS_DEBUG
1845 		if (rfs->flags & RESIZE_DEBUG_BMOVE)
1846 			printf("Moving %llu blocks %llu->%llu\n",
1847 			       (unsigned long long) size,
1848 			       (unsigned long long) old_blk,
1849 			       (unsigned long long) new_blk);
1850 #endif
1851 		do {
1852 			c = size;
1853 			if (c > fs->inode_blocks_per_group)
1854 				c = fs->inode_blocks_per_group;
1855 			retval = io_channel_read_blk64(fs->io, old_blk, c,
1856 						       rfs->itable_buf);
1857 			if (retval) goto errout;
1858 			retval = io_channel_write_blk64(fs->io, new_blk, c,
1859 							rfs->itable_buf);
1860 			if (retval) goto errout;
1861 			size -= c;
1862 			new_blk += c;
1863 			old_blk += c;
1864 			moved += c;
1865 			if (rfs->progress) {
1866 				io_channel_flush(fs->io);
1867 				retval = (rfs->progress)(rfs,
1868 						E2_RSZ_BLOCK_RELOC_PASS,
1869 						moved, to_move);
1870 				if (retval)
1871 					goto errout;
1872 			}
1873 		} while (size > 0);
1874 		io_channel_flush(fs->io);
1875 	}
1876 
1877 errout:
1878 	if (badblock_list) {
1879 		if (!retval && bb_modified)
1880 			retval = ext2fs_update_bb_inode(old_fs,
1881 							badblock_list);
1882 		ext2fs_badblocks_list_free(badblock_list);
1883 	}
1884 	return retval;
1885 }
1886 
1887 
1888 /* --------------------------------------------------------------------
1889  *
1890  * Resize processing, phase 3
1891  *
1892  * --------------------------------------------------------------------
1893  */
1894 
1895 
1896 /*
1897  * The extent translation table is stored in clusters so we need to
1898  * take special care when mapping a source block number to its
1899  * destination block number.
1900  */
extent_translate(ext2_filsys fs,ext2_extent extent,__u64 old_loc)1901 static __u64 extent_translate(ext2_filsys fs, ext2_extent extent, __u64 old_loc)
1902 {
1903 	__u64 new_block = C2B(ext2fs_extent_translate(extent, B2C(old_loc)));
1904 
1905 	if (new_block != 0)
1906 		new_block += old_loc & (EXT2FS_CLUSTER_RATIO(fs) - 1);
1907 	return new_block;
1908 }
1909 
1910 struct process_block_struct {
1911 	ext2_resize_t 		rfs;
1912 	ext2_ino_t		ino;
1913 	ext2_ino_t		old_ino;
1914 	struct ext2_inode *	inode;
1915 	errcode_t		error;
1916 	int			is_dir;
1917 	int			changed;
1918 	int			has_extents;
1919 };
1920 
process_block(ext2_filsys fs,blk64_t * block_nr,e2_blkcnt_t blockcnt,blk64_t ref_block EXT2FS_ATTR ((unused)),int ref_offset EXT2FS_ATTR ((unused)),void * priv_data)1921 static int process_block(ext2_filsys fs, blk64_t	*block_nr,
1922 			 e2_blkcnt_t blockcnt,
1923 			 blk64_t ref_block EXT2FS_ATTR((unused)),
1924 			 int ref_offset EXT2FS_ATTR((unused)), void *priv_data)
1925 {
1926 	struct process_block_struct *pb;
1927 	errcode_t	retval;
1928 	blk64_t		block, new_block;
1929 	int		ret = 0;
1930 
1931 	pb = (struct process_block_struct *) priv_data;
1932 	block = *block_nr;
1933 	if (pb->rfs->bmap) {
1934 		new_block = extent_translate(fs, pb->rfs->bmap, block);
1935 		if (new_block) {
1936 			*block_nr = new_block;
1937 			ret |= BLOCK_CHANGED;
1938 			pb->changed = 1;
1939 #ifdef RESIZE2FS_DEBUG
1940 			if (pb->rfs->flags & RESIZE_DEBUG_BMOVE)
1941 				printf("ino=%u, blockcnt=%lld, %llu->%llu\n",
1942 				       pb->old_ino, (long long) blockcnt,
1943 				       (unsigned long long) block,
1944 				       (unsigned long long) new_block);
1945 #endif
1946 			block = new_block;
1947 		}
1948 	}
1949 
1950 	if (pb->is_dir) {
1951 		retval = ext2fs_add_dir_block2(fs->dblist, pb->ino,
1952 					       block, (int) blockcnt);
1953 		if (retval) {
1954 			pb->error = retval;
1955 			ret |= BLOCK_ABORT;
1956 		}
1957 	}
1958 	return ret;
1959 }
1960 
1961 /*
1962  * Progress callback
1963  */
progress_callback(ext2_filsys fs,ext2_inode_scan scan EXT2FS_ATTR ((unused)),dgrp_t group,void * priv_data)1964 static errcode_t progress_callback(ext2_filsys fs,
1965 				   ext2_inode_scan scan EXT2FS_ATTR((unused)),
1966 				   dgrp_t group, void * priv_data)
1967 {
1968 	ext2_resize_t rfs = (ext2_resize_t) priv_data;
1969 	errcode_t		retval;
1970 
1971 	/*
1972 	 * This check is to protect against old ext2 libraries.  It
1973 	 * shouldn't be needed against new libraries.
1974 	 */
1975 	if ((group+1) == 0)
1976 		return 0;
1977 
1978 	if (rfs->progress) {
1979 		io_channel_flush(fs->io);
1980 		retval = (rfs->progress)(rfs, E2_RSZ_INODE_SCAN_PASS,
1981 					 group+1, fs->group_desc_count);
1982 		if (retval)
1983 			return retval;
1984 	}
1985 
1986 	return 0;
1987 }
1988 
migrate_ea_block(ext2_resize_t rfs,ext2_ino_t ino,struct ext2_inode * inode,int * changed)1989 static errcode_t migrate_ea_block(ext2_resize_t rfs, ext2_ino_t ino,
1990 				  struct ext2_inode *inode, int *changed)
1991 {
1992 	char *buf = NULL;
1993 	blk64_t new_block;
1994 	errcode_t err = 0;
1995 
1996 	/* No EA block or no remapping?  Quit early. */
1997 	if (ext2fs_file_acl_block(rfs->old_fs, inode) == 0 || !rfs->bmap)
1998 		return 0;
1999 	new_block = extent_translate(rfs->old_fs, rfs->bmap,
2000 		ext2fs_file_acl_block(rfs->old_fs, inode));
2001 	if (new_block == 0)
2002 		return 0;
2003 
2004 	/* Set the new ACL block */
2005 	ext2fs_file_acl_block_set(rfs->old_fs, inode, new_block);
2006 
2007 	/* Update checksum */
2008 	if (ext2fs_has_feature_metadata_csum(rfs->new_fs->super)) {
2009 		err = ext2fs_get_mem(rfs->old_fs->blocksize, &buf);
2010 		if (err)
2011 			return err;
2012 		rfs->old_fs->flags |= EXT2_FLAG_IGNORE_CSUM_ERRORS;
2013 		err = ext2fs_read_ext_attr3(rfs->old_fs, new_block, buf, ino);
2014 		rfs->old_fs->flags &= ~EXT2_FLAG_IGNORE_CSUM_ERRORS;
2015 		if (err)
2016 			goto out;
2017 		err = ext2fs_write_ext_attr3(rfs->old_fs, new_block, buf, ino);
2018 		if (err)
2019 			goto out;
2020 	}
2021 	*changed = 1;
2022 
2023 out:
2024 	ext2fs_free_mem(&buf);
2025 	return err;
2026 }
2027 
quiet_com_err_proc(const char * whoami EXT2FS_ATTR ((unused)),errcode_t code EXT2FS_ATTR ((unused)),const char * fmt EXT2FS_ATTR ((unused)),va_list args EXT2FS_ATTR ((unused)))2028 static void quiet_com_err_proc(const char *whoami EXT2FS_ATTR((unused)),
2029 			       errcode_t code EXT2FS_ATTR((unused)),
2030 			       const char *fmt EXT2FS_ATTR((unused)),
2031 			       va_list args EXT2FS_ATTR((unused)))
2032 {
2033 }
2034 
fix_ea_entries(ext2_extent imap,struct ext2_ext_attr_entry * entry,struct ext2_ext_attr_entry * end,ext2_ino_t last_ino)2035 static int fix_ea_entries(ext2_extent imap, struct ext2_ext_attr_entry *entry,
2036 			  struct ext2_ext_attr_entry *end, ext2_ino_t last_ino)
2037 {
2038 	int modified = 0;
2039 	ext2_ino_t new_ino;
2040 
2041 	while (entry < end && !EXT2_EXT_IS_LAST_ENTRY(entry)) {
2042 		if (entry->e_value_inum > last_ino) {
2043 			new_ino = ext2fs_extent_translate(imap,
2044 							  entry->e_value_inum);
2045 			entry->e_value_inum = new_ino;
2046 			modified = 1;
2047 		}
2048 		entry = EXT2_EXT_ATTR_NEXT(entry);
2049 	}
2050 	return modified;
2051 }
2052 
fix_ea_ibody_entries(ext2_extent imap,struct ext2_inode_large * inode,int inode_size,ext2_ino_t last_ino)2053 static int fix_ea_ibody_entries(ext2_extent imap,
2054 				struct ext2_inode_large *inode, int inode_size,
2055 				ext2_ino_t last_ino)
2056 {
2057 	struct ext2_ext_attr_entry *start, *end;
2058 	__u32 *ea_magic;
2059 
2060 	if (inode->i_extra_isize == 0)
2061 		return 0;
2062 
2063 	ea_magic = (__u32 *)((char *)inode + EXT2_GOOD_OLD_INODE_SIZE +
2064 				inode->i_extra_isize);
2065 	if (*ea_magic != EXT2_EXT_ATTR_MAGIC)
2066 		return 0;
2067 
2068 	start = (struct ext2_ext_attr_entry *)(ea_magic + 1);
2069 	end = (struct ext2_ext_attr_entry *)((char *)inode + inode_size);
2070 
2071 	return fix_ea_entries(imap, start, end, last_ino);
2072 }
2073 
fix_ea_block_entries(ext2_extent imap,char * block_buf,unsigned int blocksize,ext2_ino_t last_ino)2074 static int fix_ea_block_entries(ext2_extent imap, char *block_buf,
2075 				unsigned int blocksize, ext2_ino_t last_ino)
2076 {
2077 	struct ext2_ext_attr_header *header;
2078 	struct ext2_ext_attr_entry *start, *end;
2079 
2080 	header = (struct ext2_ext_attr_header *)block_buf;
2081 	start = (struct ext2_ext_attr_entry *)(header+1);
2082 	end = (struct ext2_ext_attr_entry *)(block_buf + blocksize);
2083 
2084 	return fix_ea_entries(imap, start, end, last_ino);
2085 }
2086 
2087 /* A simple LRU cache to check recently processed blocks. */
2088 struct blk_cache {
2089 	int cursor;
2090 	blk64_t blks[4];
2091 };
2092 
2093 #define BLK_IN_CACHE(b,c) ((b) == (c).blks[0] || (b) == (c).blks[1] || \
2094 			   (b) == (c).blks[2] || (b) == (c).blks[3])
2095 #define BLK_ADD_CACHE(b,c) { 			\
2096 	(c).blks[(c).cursor] = (b);		\
2097 	(c).cursor = ((c).cursor + 1) % 4;	\
2098 }
2099 
fix_ea_inode_refs(ext2_resize_t rfs,struct ext2_inode * inode,char * block_buf,ext2_ino_t last_ino)2100 static errcode_t fix_ea_inode_refs(ext2_resize_t rfs, struct ext2_inode *inode,
2101 				   char *block_buf, ext2_ino_t last_ino)
2102 {
2103 	ext2_filsys	fs = rfs->new_fs;
2104 	ext2_inode_scan	scan = NULL;
2105 	ext2_ino_t	ino;
2106 	int		inode_size = EXT2_INODE_SIZE(fs->super);
2107 	blk64_t		blk;
2108 	int		modified;
2109 	struct blk_cache blk_cache;
2110 	struct ext2_ext_attr_header *header;
2111 	errcode_t		retval;
2112 
2113 	memset(&blk_cache, 0, sizeof(blk_cache));
2114 
2115 	header = (struct ext2_ext_attr_header *)block_buf;
2116 
2117 	retval = ext2fs_open_inode_scan(fs, 0, &scan);
2118 	if (retval)
2119 		goto out;
2120 
2121 	while (1) {
2122 		retval = ext2fs_get_next_inode_full(scan, &ino, inode,
2123 						    inode_size);
2124 		if (retval)
2125 			goto out;
2126 		if (!ino)
2127 			break;
2128 
2129 		if (inode->i_links_count == 0 && ino != EXT2_RESIZE_INO)
2130 			continue; /* inode not in use */
2131 
2132 		if (inode_size != EXT2_GOOD_OLD_INODE_SIZE) {
2133 			modified = fix_ea_ibody_entries(rfs->imap,
2134 					(struct ext2_inode_large *)inode,
2135 					inode_size, last_ino);
2136 			if (modified) {
2137 				retval = ext2fs_write_inode_full(fs, ino, inode,
2138 								 inode_size);
2139 				if (retval)
2140 					goto out;
2141 			}
2142 		}
2143 
2144 		blk = ext2fs_file_acl_block(fs, inode);
2145 		if (blk && !BLK_IN_CACHE(blk, blk_cache)) {
2146 			retval = ext2fs_read_ext_attr3(fs, blk, block_buf, ino);
2147 			if (retval)
2148 				goto out;
2149 
2150 			modified = fix_ea_block_entries(rfs->imap, block_buf,
2151 							fs->blocksize,
2152 							last_ino);
2153 			if (modified) {
2154 				retval = ext2fs_write_ext_attr3(fs, blk,
2155 								block_buf, ino);
2156 				if (retval)
2157 					goto out;
2158 				/*
2159 				 * If refcount is greater than 1, we might see
2160 				 * the same block referenced by other inodes
2161 				 * later.
2162 				 */
2163 				if (header->h_refcount > 1)
2164 					BLK_ADD_CACHE(blk, blk_cache);
2165 			}
2166 		}
2167 	}
2168 	retval = 0;
2169 out:
2170 	if (scan)
2171 		ext2fs_close_inode_scan(scan);
2172 	return retval;
2173 
2174 }
inode_scan_and_fix(ext2_resize_t rfs)2175 static errcode_t inode_scan_and_fix(ext2_resize_t rfs)
2176 {
2177 	struct process_block_struct	pb;
2178 	ext2_ino_t		ino, new_inode;
2179 	struct ext2_inode 	*inode = NULL;
2180 	ext2_inode_scan 	scan = NULL;
2181 	errcode_t		retval;
2182 	char			*block_buf = 0;
2183 	ext2_ino_t		start_to_move;
2184 	int			inode_size;
2185 	int			update_ea_inode_refs = 0;
2186 
2187 	if ((rfs->old_fs->group_desc_count <=
2188 	     rfs->new_fs->group_desc_count) &&
2189 	    !rfs->bmap)
2190 		return 0;
2191 
2192 	set_com_err_hook(quiet_com_err_proc);
2193 
2194 	retval = ext2fs_open_inode_scan(rfs->old_fs, 0, &scan);
2195 	if (retval) goto errout;
2196 
2197 	retval = ext2fs_init_dblist(rfs->old_fs, 0);
2198 	if (retval) goto errout;
2199 	retval = ext2fs_get_array(rfs->old_fs->blocksize, 3, &block_buf);
2200 	if (retval) goto errout;
2201 
2202 	start_to_move = (rfs->new_fs->group_desc_count *
2203 			 rfs->new_fs->super->s_inodes_per_group);
2204 
2205 	if (rfs->progress) {
2206 		retval = (rfs->progress)(rfs, E2_RSZ_INODE_SCAN_PASS,
2207 					 0, rfs->old_fs->group_desc_count);
2208 		if (retval)
2209 			goto errout;
2210 	}
2211 	ext2fs_set_inode_callback(scan, progress_callback, (void *) rfs);
2212 	pb.rfs = rfs;
2213 	pb.inode = inode;
2214 	pb.error = 0;
2215 	new_inode = EXT2_FIRST_INODE(rfs->new_fs->super);
2216 	inode_size = EXT2_INODE_SIZE(rfs->new_fs->super);
2217 	inode = malloc(inode_size);
2218 	if (!inode) {
2219 		retval = ENOMEM;
2220 		goto errout;
2221 	}
2222 	/*
2223 	 * First, copy all of the inodes that need to be moved
2224 	 * elsewhere in the inode table
2225 	 */
2226 	while (1) {
2227 		retval = ext2fs_get_next_inode_full(scan, &ino, inode, inode_size);
2228 		if (retval) goto errout;
2229 		if (!ino)
2230 			break;
2231 
2232 		if (inode->i_links_count == 0 && ino != EXT2_RESIZE_INO)
2233 			continue; /* inode not in use */
2234 
2235 		pb.is_dir = LINUX_S_ISDIR(inode->i_mode);
2236 		pb.changed = 0;
2237 
2238 		/* Remap EA block */
2239 		retval = migrate_ea_block(rfs, ino, inode, &pb.changed);
2240 		if (retval)
2241 			goto errout;
2242 
2243 		new_inode = ino;
2244 		if (ino <= start_to_move)
2245 			goto remap_blocks; /* Don't need to move inode. */
2246 
2247 		/*
2248 		 * Find a new inode.  Now that extents and directory blocks
2249 		 * are tied to the inode number through the checksum, we must
2250 		 * set up the new inode before we start rewriting blocks.
2251 		 */
2252 		retval = ext2fs_new_inode(rfs->new_fs, 0, 0, 0, &new_inode);
2253 		if (retval)
2254 			goto errout;
2255 
2256 		ext2fs_inode_alloc_stats2(rfs->new_fs, new_inode, +1,
2257 					  pb.is_dir);
2258 		/*
2259 		 * i_ctime field in xattr inodes contain a portion of the ref
2260 		 * count, do not overwrite.
2261 		 */
2262 		if (inode->i_flags & EXT4_EA_INODE_FL)
2263 			update_ea_inode_refs = 1;
2264 		else
2265 			inode->i_ctime = rfs->old_fs->now ?
2266 				rfs->old_fs->now : time(0);
2267 
2268 		retval = ext2fs_write_inode_full(rfs->old_fs, new_inode,
2269 						inode, inode_size);
2270 		if (retval)
2271 			goto errout;
2272 		pb.changed = 0;
2273 
2274 #ifdef RESIZE2FS_DEBUG
2275 		if (rfs->flags & RESIZE_DEBUG_INODEMAP)
2276 			printf("Inode moved %u->%u\n", ino, new_inode);
2277 #endif
2278 		if (!rfs->imap) {
2279 			retval = ext2fs_create_extent_table(&rfs->imap, 0);
2280 			if (retval)
2281 				goto errout;
2282 		}
2283 		ext2fs_add_extent_entry(rfs->imap, ino, new_inode);
2284 
2285 remap_blocks:
2286 		if (pb.changed)
2287 			retval = ext2fs_write_inode_full(rfs->old_fs,
2288 							 new_inode,
2289 							 inode, inode_size);
2290 		if (retval)
2291 			goto errout;
2292 
2293 		/*
2294 		 * Update inodes to point to new blocks; schedule directory
2295 		 * blocks for inode remapping.  Need to write out dir blocks
2296 		 * with new inode numbers if we have metadata_csum enabled.
2297 		 */
2298 		rfs->old_fs->flags |= EXT2_FLAG_IGNORE_CSUM_ERRORS;
2299 		if (ext2fs_inode_has_valid_blocks2(rfs->old_fs, inode) &&
2300 		    (rfs->bmap || pb.is_dir)) {
2301 			pb.ino = new_inode;
2302 			pb.old_ino = ino;
2303 			pb.has_extents = inode->i_flags & EXT4_EXTENTS_FL;
2304 			retval = ext2fs_block_iterate3(rfs->old_fs,
2305 						       new_inode, 0, block_buf,
2306 						       process_block, &pb);
2307 			if (retval)
2308 				goto errout;
2309 			if (pb.error) {
2310 				retval = pb.error;
2311 				goto errout;
2312 			}
2313 		} else if ((inode->i_flags & EXT4_INLINE_DATA_FL) &&
2314 			   (rfs->bmap || pb.is_dir)) {
2315 			/* inline data dir; update it too */
2316 			retval = ext2fs_add_dir_block2(rfs->old_fs->dblist,
2317 						       new_inode, 0, 0);
2318 			if (retval)
2319 				goto errout;
2320 		}
2321 
2322 		/* Fix up extent block checksums with the new inode number */
2323 		if (ext2fs_has_feature_metadata_csum(rfs->old_fs->super) &&
2324 		    (inode->i_flags & EXT4_EXTENTS_FL)) {
2325 			retval = ext2fs_fix_extents_checksums(rfs->old_fs,
2326 							      new_inode, NULL);
2327 			if (retval)
2328 				goto errout;
2329 		}
2330 	}
2331 
2332 	if (update_ea_inode_refs &&
2333 	    ext2fs_has_feature_ea_inode(rfs->new_fs->super)) {
2334 		retval = fix_ea_inode_refs(rfs, inode, block_buf,
2335 					   start_to_move);
2336 		if (retval)
2337 			goto errout;
2338 	}
2339 	io_channel_flush(rfs->old_fs->io);
2340 
2341 errout:
2342 	reset_com_err_hook();
2343 	rfs->old_fs->flags &= ~EXT2_FLAG_IGNORE_CSUM_ERRORS;
2344 	if (rfs->bmap) {
2345 		ext2fs_free_extent_table(rfs->bmap);
2346 		rfs->bmap = 0;
2347 	}
2348 	if (scan)
2349 		ext2fs_close_inode_scan(scan);
2350 	if (block_buf)
2351 		ext2fs_free_mem(&block_buf);
2352 	free(inode);
2353 	return retval;
2354 }
2355 
2356 /* --------------------------------------------------------------------
2357  *
2358  * Resize processing, phase 4.
2359  *
2360  * --------------------------------------------------------------------
2361  */
2362 
2363 struct istruct {
2364 	ext2_resize_t rfs;
2365 	errcode_t	err;
2366 	unsigned int	max_dirs;
2367 	unsigned int	num;
2368 };
2369 
check_and_change_inodes(ext2_ino_t dir,int entry EXT2FS_ATTR ((unused)),struct ext2_dir_entry * dirent,int offset,int blocksize EXT2FS_ATTR ((unused)),char * buf EXT2FS_ATTR ((unused)),void * priv_data)2370 static int check_and_change_inodes(ext2_ino_t dir,
2371 				   int entry EXT2FS_ATTR((unused)),
2372 				   struct ext2_dir_entry *dirent, int offset,
2373 				   int	blocksize EXT2FS_ATTR((unused)),
2374 				   char *buf EXT2FS_ATTR((unused)),
2375 				   void *priv_data)
2376 {
2377 	struct istruct *is = (struct istruct *) priv_data;
2378 	struct ext2_inode 	inode;
2379 	ext2_ino_t		new_inode;
2380 	errcode_t		retval;
2381 	int			ret = 0;
2382 
2383 	if (is->rfs->progress && offset == 0) {
2384 		io_channel_flush(is->rfs->old_fs->io);
2385 		is->err = (is->rfs->progress)(is->rfs,
2386 					      E2_RSZ_INODE_REF_UPD_PASS,
2387 					      ++is->num, is->max_dirs);
2388 		if (is->err)
2389 			return DIRENT_ABORT;
2390 	}
2391 
2392 	/*
2393 	 * If we have checksums enabled and the inode wasn't present in the
2394 	 * old fs, then we must rewrite all dir blocks with new checksums.
2395 	 */
2396 	if (ext2fs_has_feature_metadata_csum(is->rfs->old_fs->super) &&
2397 	    !ext2fs_test_inode_bitmap2(is->rfs->old_fs->inode_map, dir))
2398 		ret |= DIRENT_CHANGED;
2399 
2400 	if (!dirent->inode)
2401 		return ret;
2402 
2403 	new_inode = ext2fs_extent_translate(is->rfs->imap, dirent->inode);
2404 
2405 	if (!new_inode)
2406 		return ret;
2407 #ifdef RESIZE2FS_DEBUG
2408 	if (is->rfs->flags & RESIZE_DEBUG_INODEMAP)
2409 		printf("Inode translate (dir=%u, name=%.*s, %u->%u)\n",
2410 		       dir, ext2fs_dirent_name_len(dirent), dirent->name,
2411 		       dirent->inode, new_inode);
2412 #endif
2413 
2414 	dirent->inode = new_inode;
2415 
2416 	/* Update the directory mtime and ctime */
2417 	retval = ext2fs_read_inode(is->rfs->old_fs, dir, &inode);
2418 	if (retval == 0) {
2419 		inode.i_mtime = inode.i_ctime = is->rfs->old_fs->now ?
2420 			is->rfs->old_fs->now : time(0);
2421 		is->err = ext2fs_write_inode(is->rfs->old_fs, dir, &inode);
2422 		if (is->err)
2423 			return ret | DIRENT_ABORT;
2424 	}
2425 
2426 	return ret | DIRENT_CHANGED;
2427 }
2428 
inode_ref_fix(ext2_resize_t rfs)2429 static errcode_t inode_ref_fix(ext2_resize_t rfs)
2430 {
2431 	errcode_t		retval;
2432 	struct istruct 		is;
2433 
2434 	if (!rfs->imap)
2435 		return 0;
2436 
2437 	/*
2438 	 * Now, we iterate over all of the directories to update the
2439 	 * inode references
2440 	 */
2441 	is.num = 0;
2442 	is.max_dirs = ext2fs_dblist_count2(rfs->old_fs->dblist);
2443 	is.rfs = rfs;
2444 	is.err = 0;
2445 
2446 	if (rfs->progress) {
2447 		retval = (rfs->progress)(rfs, E2_RSZ_INODE_REF_UPD_PASS,
2448 					 0, is.max_dirs);
2449 		if (retval)
2450 			goto errout;
2451 	}
2452 
2453 	rfs->old_fs->flags |= EXT2_FLAG_IGNORE_CSUM_ERRORS;
2454 	retval = ext2fs_dblist_dir_iterate(rfs->old_fs->dblist,
2455 					   DIRENT_FLAG_INCLUDE_EMPTY, 0,
2456 					   check_and_change_inodes, &is);
2457 	rfs->old_fs->flags &= ~EXT2_FLAG_IGNORE_CSUM_ERRORS;
2458 	if (retval)
2459 		goto errout;
2460 	if (is.err) {
2461 		retval = is.err;
2462 		goto errout;
2463 	}
2464 
2465 	if (rfs->progress && (is.num < is.max_dirs))
2466 		(rfs->progress)(rfs, E2_RSZ_INODE_REF_UPD_PASS,
2467 				is.max_dirs, is.max_dirs);
2468 
2469 errout:
2470 	ext2fs_free_extent_table(rfs->imap);
2471 	rfs->imap = 0;
2472 	return retval;
2473 }
2474 
2475 
2476 /* --------------------------------------------------------------------
2477  *
2478  * Resize processing, phase 5.
2479  *
2480  * In this phase we actually move the inode table around, and then
2481  * update the summary statistics.  This is scary, since aborting here
2482  * will potentially scramble the filesystem.  (We are moving the
2483  * inode tables around in place, and so the potential for lost data,
2484  * or at the very least scrambling the mapping between filenames and
2485  * inode numbers is very high in case of a power failure here.)
2486  * --------------------------------------------------------------------
2487  */
2488 
2489 
2490 /*
2491  * A very scary routine --- this one moves the inode table around!!!
2492  *
2493  * After this you have to use the rfs->new_fs file handle to read and
2494  * write inodes.
2495  */
move_itables(ext2_resize_t rfs)2496 static errcode_t move_itables(ext2_resize_t rfs)
2497 {
2498 	int		n, num, size;
2499 	long long	diff;
2500 	dgrp_t		i, max_groups;
2501 	ext2_filsys	fs = rfs->new_fs;
2502 	char		*cp;
2503 	blk64_t		old_blk, new_blk, blk, cluster_freed;
2504 	errcode_t	retval;
2505 	int		to_move, moved;
2506 	unsigned int	j;
2507 	ext2fs_block_bitmap	new_bmap = NULL;
2508 
2509 	max_groups = fs->group_desc_count;
2510 	if (max_groups > rfs->old_fs->group_desc_count)
2511 		max_groups = rfs->old_fs->group_desc_count;
2512 
2513 	size = fs->blocksize * fs->inode_blocks_per_group;
2514 	if (!rfs->itable_buf) {
2515 		retval = ext2fs_get_mem(size, &rfs->itable_buf);
2516 		if (retval)
2517 			return retval;
2518 	}
2519 
2520 	if (EXT2FS_CLUSTER_RATIO(fs) > 1) {
2521 		retval = ext2fs_allocate_block_bitmap(fs, _("new meta blocks"),
2522 						      &new_bmap);
2523 		if (retval)
2524 			return retval;
2525 
2526 		retval = mark_table_blocks(fs, new_bmap);
2527 		if (retval)
2528 			goto errout;
2529 	}
2530 
2531 	/*
2532 	 * Figure out how many inode tables we need to move
2533 	 */
2534 	to_move = moved = 0;
2535 	for (i=0; i < max_groups; i++)
2536 		if (ext2fs_inode_table_loc(rfs->old_fs, i) !=
2537 		    ext2fs_inode_table_loc(fs, i))
2538 			to_move++;
2539 
2540 	if (to_move == 0) {
2541 		retval = 0;
2542 		goto errout;
2543 	}
2544 
2545 	if (rfs->progress) {
2546 		retval = rfs->progress(rfs, E2_RSZ_MOVE_ITABLE_PASS,
2547 				       0, to_move);
2548 		if (retval)
2549 			goto errout;
2550 	}
2551 
2552 	rfs->old_fs->flags |= EXT2_FLAG_MASTER_SB_ONLY;
2553 
2554 	for (i=0; i < max_groups; i++) {
2555 		old_blk = ext2fs_inode_table_loc(rfs->old_fs, i);
2556 		new_blk = ext2fs_inode_table_loc(fs, i);
2557 		diff = new_blk - old_blk;
2558 
2559 #ifdef RESIZE2FS_DEBUG
2560 		if (rfs->flags & RESIZE_DEBUG_ITABLEMOVE)
2561 			printf("Itable move group %d block %llu->%llu (diff %lld)\n",
2562 			       i, (unsigned long long) old_blk,
2563 			       (unsigned long long) new_blk, diff);
2564 #endif
2565 
2566 		if (!diff)
2567 			continue;
2568 		if (diff < 0)
2569 			diff = 0;
2570 
2571 		retval = io_channel_read_blk64(fs->io, old_blk,
2572 					       fs->inode_blocks_per_group,
2573 					       rfs->itable_buf);
2574 		if (retval)
2575 			goto errout;
2576 		/*
2577 		 * The end of the inode table segment often contains
2578 		 * all zeros, and we're often only moving the inode
2579 		 * table down a block or two.  If so, we can optimize
2580 		 * things by not rewriting blocks that we know to be zero
2581 		 * already.
2582 		 */
2583 		for (cp = rfs->itable_buf+size-1, n=0; n < size; n++, cp--)
2584 			if (*cp)
2585 				break;
2586 		n = n >> EXT2_BLOCK_SIZE_BITS(fs->super);
2587 #ifdef RESIZE2FS_DEBUG
2588 		if (rfs->flags & RESIZE_DEBUG_ITABLEMOVE)
2589 			printf("%d blocks of zeros...\n", n);
2590 #endif
2591 		num = fs->inode_blocks_per_group;
2592 		if (n > diff)
2593 			num -= n;
2594 
2595 		retval = io_channel_write_blk64(fs->io, new_blk,
2596 						num, rfs->itable_buf);
2597 		if (retval) {
2598 			io_channel_write_blk64(fs->io, old_blk,
2599 					       num, rfs->itable_buf);
2600 			goto errout;
2601 		}
2602 		if (n > diff) {
2603 			retval = io_channel_write_blk64(fs->io,
2604 			      old_blk + fs->inode_blocks_per_group,
2605 			      diff, (rfs->itable_buf +
2606 				     (fs->inode_blocks_per_group - diff) *
2607 				     fs->blocksize));
2608 			if (retval)
2609 				goto errout;
2610 		}
2611 
2612 		for (blk = ext2fs_inode_table_loc(rfs->old_fs, i), j=0;
2613 		     j < fs->inode_blocks_per_group;) {
2614 			if (new_bmap == NULL ||
2615 			    !ext2fs_test_block_bitmap2(new_bmap, blk)) {
2616 				ext2fs_block_alloc_stats2(fs, blk, -1);
2617 				cluster_freed = EXT2FS_CLUSTER_RATIO(fs) -
2618 						(blk & EXT2FS_CLUSTER_MASK(fs));
2619 				blk += cluster_freed;
2620 				j += cluster_freed;
2621 				continue;
2622 			}
2623 			blk++;
2624 			j++;
2625 		}
2626 
2627 		ext2fs_inode_table_loc_set(rfs->old_fs, i, new_blk);
2628 		ext2fs_group_desc_csum_set(rfs->old_fs, i);
2629 		ext2fs_mark_super_dirty(rfs->old_fs);
2630 		ext2fs_flush(rfs->old_fs);
2631 
2632 		if (rfs->progress) {
2633 			retval = rfs->progress(rfs, E2_RSZ_MOVE_ITABLE_PASS,
2634 					       ++moved, to_move);
2635 			if (retval)
2636 				goto errout;
2637 		}
2638 	}
2639 	mark_table_blocks(fs, fs->block_map);
2640 	ext2fs_flush(fs);
2641 #ifdef RESIZE2FS_DEBUG
2642 	if (rfs->flags & RESIZE_DEBUG_ITABLEMOVE)
2643 		printf("Inode table move finished.\n");
2644 #endif
2645 	retval = 0;
2646 
2647 errout:
2648 	if (new_bmap)
2649 		ext2fs_free_block_bitmap(new_bmap);
2650 	return retval;
2651 }
2652 
2653 /*
2654  * This function is used when expanding a file system.  It frees the
2655  * superblock and block group descriptor blocks from the block group
2656  * which is no longer the last block group.
2657  */
clear_sparse_super2_last_group(ext2_resize_t rfs)2658 static errcode_t clear_sparse_super2_last_group(ext2_resize_t rfs)
2659 {
2660 	ext2_filsys	fs = rfs->new_fs;
2661 	ext2_filsys	old_fs = rfs->old_fs;
2662 	errcode_t	retval;
2663 	dgrp_t		old_last_bg = rfs->old_fs->group_desc_count - 1;
2664 	dgrp_t		last_bg = fs->group_desc_count - 1;
2665 	blk64_t		sb, old_desc;
2666 	blk_t		num;
2667 
2668 	if (!ext2fs_has_feature_sparse_super2(fs->super))
2669 		return 0;
2670 
2671 	if (last_bg <= old_last_bg)
2672 		return 0;
2673 
2674 	if (fs->super->s_backup_bgs[0] == old_fs->super->s_backup_bgs[0] &&
2675 	    fs->super->s_backup_bgs[1] == old_fs->super->s_backup_bgs[1])
2676 		return 0;
2677 
2678 	if (old_fs->super->s_backup_bgs[0] != old_last_bg &&
2679 	    old_fs->super->s_backup_bgs[1] != old_last_bg)
2680 		return 0;
2681 
2682 	if (fs->super->s_backup_bgs[0] == old_last_bg ||
2683 	    fs->super->s_backup_bgs[1] == old_last_bg)
2684 		return 0;
2685 
2686 	if (old_last_bg == 0)
2687 		return 0;
2688 
2689 	retval = ext2fs_super_and_bgd_loc2(rfs->old_fs, old_last_bg,
2690 					   &sb, &old_desc, NULL, &num);
2691 	if (retval)
2692 		return retval;
2693 
2694 	if (sb)
2695 		ext2fs_unmark_block_bitmap2(fs->block_map, sb);
2696 	if (old_desc)
2697 		ext2fs_unmark_block_bitmap_range2(fs->block_map, old_desc, num);
2698 	return 0;
2699 }
2700 
2701 /*
2702  * This function is used when shrinking a file system.  We need to
2703  * utilize blocks from what will be the new last block group for the
2704  * backup superblock and block group descriptor blocks.
2705  * Unfortunately, those blocks may be used by other files or fs
2706  * metadata blocks.  We need to mark them as being in use.
2707  */
reserve_sparse_super2_last_group(ext2_resize_t rfs,ext2fs_block_bitmap meta_bmap)2708 static errcode_t reserve_sparse_super2_last_group(ext2_resize_t rfs,
2709 						 ext2fs_block_bitmap meta_bmap)
2710 {
2711 	ext2_filsys	fs = rfs->new_fs;
2712 	ext2_filsys	old_fs = rfs->old_fs;
2713 	errcode_t	retval;
2714 	dgrp_t		old_last_bg = rfs->old_fs->group_desc_count - 1;
2715 	dgrp_t		last_bg = fs->group_desc_count - 1;
2716 	dgrp_t		g;
2717 	blk64_t		blk, sb, old_desc;
2718 	blk_t		i, num;
2719 	int		realloc = 0;
2720 
2721 	if (!ext2fs_has_feature_sparse_super2(fs->super))
2722 		return 0;
2723 
2724 	if (last_bg >= old_last_bg)
2725 		return 0;
2726 
2727 	if (fs->super->s_backup_bgs[0] == old_fs->super->s_backup_bgs[0] &&
2728 	    fs->super->s_backup_bgs[1] == old_fs->super->s_backup_bgs[1])
2729 		return 0;
2730 
2731 	if (fs->super->s_backup_bgs[0] != last_bg &&
2732 	    fs->super->s_backup_bgs[1] != last_bg)
2733 		return 0;
2734 
2735 	if (old_fs->super->s_backup_bgs[0] == last_bg ||
2736 	    old_fs->super->s_backup_bgs[1] == last_bg)
2737 		return 0;
2738 
2739 	retval = ext2fs_super_and_bgd_loc2(rfs->new_fs, last_bg,
2740 					   &sb, &old_desc, NULL, &num);
2741 	if (retval)
2742 		return retval;
2743 
2744 	if (last_bg && !sb) {
2745 		fputs(_("Should never happen!  No sb in last super_sparse bg?\n"),
2746 		      stderr);
2747 		exit(1);
2748 	}
2749 	if (old_desc && old_desc != sb+1) {
2750 		fputs(_("Should never happen!  Unexpected old_desc in "
2751 			"super_sparse bg?\n"),
2752 		      stderr);
2753 		exit(1);
2754 	}
2755 	num = (old_desc) ? num : 1;
2756 
2757 	/* Reserve the backup blocks */
2758 	ext2fs_mark_block_bitmap_range2(fs->block_map, sb, num);
2759 
2760 	for (g = 0; g < fs->group_desc_count; g++) {
2761 		blk64_t mb;
2762 
2763 		mb = ext2fs_block_bitmap_loc(fs, g);
2764 		if ((mb >= sb) && (mb < sb + num)) {
2765 			ext2fs_block_bitmap_loc_set(fs, g, 0);
2766 			realloc = 1;
2767 		}
2768 		mb = ext2fs_inode_bitmap_loc(fs, g);
2769 		if ((mb >= sb) && (mb < sb + num)) {
2770 			ext2fs_inode_bitmap_loc_set(fs, g, 0);
2771 			realloc = 1;
2772 		}
2773 		mb = ext2fs_inode_table_loc(fs, g);
2774 		if ((mb < sb + num) &&
2775 		    (sb < mb + fs->inode_blocks_per_group)) {
2776 			ext2fs_inode_table_loc_set(fs, g, 0);
2777 			realloc = 1;
2778 		}
2779 		if (realloc) {
2780 			retval = ext2fs_allocate_group_table(fs, g, 0);
2781 			if (retval)
2782 				return retval;
2783 		}
2784 	}
2785 
2786 	for (blk = sb, i = 0; i < num; blk++, i++) {
2787 		if (ext2fs_test_block_bitmap2(old_fs->block_map, blk) &&
2788 		    !ext2fs_test_block_bitmap2(meta_bmap, blk)) {
2789 			ext2fs_mark_block_bitmap2(rfs->move_blocks, blk);
2790 			rfs->needed_blocks++;
2791 		}
2792 		ext2fs_mark_block_bitmap2(rfs->reserve_blocks, blk);
2793 	}
2794 	return 0;
2795 }
2796 
2797 /*
2798  * Fix the resize inode
2799  */
fix_resize_inode(ext2_filsys fs)2800 static errcode_t fix_resize_inode(ext2_filsys fs)
2801 {
2802 	struct ext2_inode	inode;
2803 	errcode_t		retval;
2804 
2805 	if (!ext2fs_has_feature_resize_inode(fs->super))
2806 		return 0;
2807 
2808 	retval = ext2fs_read_inode(fs, EXT2_RESIZE_INO, &inode);
2809 	if (retval) goto errout;
2810 
2811 	ext2fs_iblk_set(fs, &inode, 1);
2812 
2813 	retval = ext2fs_write_inode(fs, EXT2_RESIZE_INO, &inode);
2814 	if (retval) goto errout;
2815 
2816 	if (!inode.i_block[EXT2_DIND_BLOCK]) {
2817 		/*
2818 		 * Avoid zeroing out block #0; that's rude.  This
2819 		 * should never happen anyway since the filesystem
2820 		 * should be fsck'ed and we assume it is consistent.
2821 		 */
2822 		fprintf(stderr, "%s",
2823 			_("Should never happen: resize inode corrupt!\n"));
2824 		exit(1);
2825 	}
2826 
2827 	retval = ext2fs_zero_blocks2(fs, inode.i_block[EXT2_DIND_BLOCK], 1,
2828 				     NULL, NULL);
2829 	if (retval)
2830 		goto errout;
2831 
2832 	retval = ext2fs_create_resize_inode(fs);
2833 	if (retval)
2834 		goto errout;
2835 
2836 errout:
2837 	return retval;
2838 }
2839 
2840 /*
2841  * Finally, recalculate the summary information
2842  */
resize2fs_calculate_summary_stats(ext2_filsys fs)2843 static errcode_t resize2fs_calculate_summary_stats(ext2_filsys fs)
2844 {
2845 	errcode_t	retval;
2846 	blk64_t		blk = fs->super->s_first_data_block;
2847 	ext2_ino_t	ino;
2848 	unsigned int	n, group, count;
2849 	blk64_t		total_clusters_free = 0;
2850 	int		total_inodes_free = 0;
2851 	int		group_free = 0;
2852 	int		uninit = 0;
2853 	char		*bitmap_buf;
2854 
2855 	/*
2856 	 * First calculate the block statistics
2857 	 */
2858 	bitmap_buf = malloc(fs->blocksize);
2859 	if (!bitmap_buf)
2860 		return ENOMEM;
2861 	for (group = 0; group < fs->group_desc_count;
2862 	     group++) {
2863 		retval = ext2fs_get_block_bitmap_range2(fs->block_map,
2864 			B2C(blk), fs->super->s_clusters_per_group, bitmap_buf);
2865 		if (retval) {
2866 			free(bitmap_buf);
2867 			return retval;
2868 		}
2869 		n = ext2fs_bitcount(bitmap_buf,
2870 				    fs->super->s_clusters_per_group / 8);
2871 		group_free = fs->super->s_clusters_per_group - n;
2872 		total_clusters_free += group_free;
2873 		ext2fs_bg_free_blocks_count_set(fs, group, group_free);
2874 		ext2fs_group_desc_csum_set(fs, group);
2875 		blk += fs->super->s_blocks_per_group;
2876 	}
2877 	free(bitmap_buf);
2878 	ext2fs_free_blocks_count_set(fs->super, C2B(total_clusters_free));
2879 
2880 	/*
2881 	 * Next, calculate the inode statistics
2882 	 */
2883 	group_free = 0;
2884 	count = 0;
2885 	group = 0;
2886 
2887 	/* Protect loop from wrap-around if s_inodes_count maxed */
2888 	uninit = ext2fs_bg_flags_test(fs, group, EXT2_BG_INODE_UNINIT);
2889 	for (ino = 1; ino <= fs->super->s_inodes_count && ino > 0; ino++) {
2890 		if (uninit ||
2891 		    !ext2fs_fast_test_inode_bitmap2(fs->inode_map, ino)) {
2892 			group_free++;
2893 			total_inodes_free++;
2894 		}
2895 		count++;
2896 		if ((count == fs->super->s_inodes_per_group) ||
2897 		    (ino == fs->super->s_inodes_count)) {
2898 			ext2fs_bg_free_inodes_count_set(fs, group, group_free);
2899 			ext2fs_group_desc_csum_set(fs, group);
2900 			group++;
2901 			if (group >= fs->group_desc_count)
2902 				break;
2903 			count = 0;
2904 			group_free = 0;
2905 			uninit = ext2fs_bg_flags_test(fs, group, EXT2_BG_INODE_UNINIT);
2906 		}
2907 	}
2908 	fs->super->s_free_inodes_count = total_inodes_free;
2909 	ext2fs_mark_super_dirty(fs);
2910 	return 0;
2911 }
2912 
2913 /*
2914  *  Journal may have been relocated; update the backup journal blocks
2915  *  in the superblock.
2916  */
fix_sb_journal_backup(ext2_filsys fs)2917 static errcode_t fix_sb_journal_backup(ext2_filsys fs)
2918 {
2919 	errcode_t	  retval;
2920 	struct ext2_inode inode;
2921 
2922 	if (!ext2fs_has_feature_journal(fs->super))
2923 		return 0;
2924 
2925 	/* External journal? Nothing to do. */
2926 	if (fs->super->s_journal_dev && !fs->super->s_journal_inum)
2927 		return 0;
2928 
2929 	retval = ext2fs_read_inode(fs, fs->super->s_journal_inum, &inode);
2930 	if (retval)
2931 		return retval;
2932 	memcpy(fs->super->s_jnl_blocks, inode.i_block, EXT2_N_BLOCKS*4);
2933 	fs->super->s_jnl_blocks[15] = inode.i_size_high;
2934 	fs->super->s_jnl_blocks[16] = inode.i_size;
2935 	fs->super->s_jnl_backup_type = EXT3_JNL_BACKUP_BLOCKS;
2936 	ext2fs_mark_super_dirty(fs);
2937 	return 0;
2938 }
2939 
calc_group_overhead(ext2_filsys fs,blk64_t grp,int old_desc_blocks)2940 static int calc_group_overhead(ext2_filsys fs, blk64_t grp,
2941 			       int old_desc_blocks)
2942 {
2943 	blk64_t	super_blk, old_desc_blk, new_desc_blk;
2944 	int overhead;
2945 
2946 	/* inode table blocks plus allocation bitmaps */
2947 	overhead = fs->inode_blocks_per_group + 2;
2948 
2949 	ext2fs_super_and_bgd_loc2(fs, grp, &super_blk,
2950 				  &old_desc_blk, &new_desc_blk, 0);
2951 	if ((grp == 0) || super_blk)
2952 		overhead++;
2953 	if (old_desc_blk)
2954 		overhead += old_desc_blocks;
2955 	else if (new_desc_blk)
2956 		overhead++;
2957 	return overhead;
2958 }
2959 
2960 
2961 /*
2962  * calculate the minimum number of blocks the given fs can be resized to
2963  */
calculate_minimum_resize_size(ext2_filsys fs,int flags)2964 blk64_t calculate_minimum_resize_size(ext2_filsys fs, int flags)
2965 {
2966 	ext2_ino_t inode_count;
2967 	dgrp_t groups, flex_groups;
2968 	blk64_t blks_needed, data_blocks;
2969 	blk64_t grp, data_needed, last_start;
2970 	blk64_t overhead = 0;
2971 	int old_desc_blocks;
2972 	unsigned flexbg_size = 1U << fs->super->s_log_groups_per_flex;
2973 
2974 	/*
2975 	 * first figure out how many group descriptors we need to
2976 	 * handle the number of inodes we have
2977 	 */
2978 	inode_count = fs->super->s_inodes_count -
2979 		fs->super->s_free_inodes_count;
2980 	blks_needed = ext2fs_div_ceil(inode_count,
2981 				      fs->super->s_inodes_per_group) *
2982 		(blk64_t) EXT2_BLOCKS_PER_GROUP(fs->super);
2983 	groups = ext2fs_div64_ceil(blks_needed,
2984 				   EXT2_BLOCKS_PER_GROUP(fs->super));
2985 #ifdef RESIZE2FS_DEBUG
2986 	if (flags & RESIZE_DEBUG_MIN_CALC)
2987 		printf("fs has %d inodes, %d groups required.\n",
2988 		       inode_count, groups);
2989 #endif
2990 
2991 	/*
2992 	 * number of old-style block group descriptor blocks
2993 	 */
2994 	if (ext2fs_has_feature_meta_bg(fs->super))
2995 		old_desc_blocks = fs->super->s_first_meta_bg;
2996 	else
2997 		old_desc_blocks = fs->desc_blocks +
2998 			fs->super->s_reserved_gdt_blocks;
2999 
3000 	/* calculate how many blocks are needed for data */
3001 	data_needed = ext2fs_blocks_count(fs->super);
3002 	for (grp = 0; grp < fs->group_desc_count; grp++) {
3003 		__u32 n = ext2fs_bg_free_blocks_count(fs, grp);
3004 
3005 		if (n > EXT2_BLOCKS_PER_GROUP(fs->super))
3006 			n = EXT2_BLOCKS_PER_GROUP(fs->super);
3007 		n += calc_group_overhead(fs, grp, old_desc_blocks);
3008 		if (data_needed < n) {
3009 			if (flags & RESIZE_DEBUG_MIN_CALC)
3010 				printf("file system appears inconsistent?!?\n");
3011 			return ext2fs_blocks_count(fs->super);
3012 		}
3013 		data_needed -= n;
3014 	}
3015 #ifdef RESIZE2FS_DEBUG
3016 	if (flags & RESIZE_DEBUG_MIN_CALC)
3017 		printf("fs requires %llu data blocks.\n",
3018 		       (unsigned long long) data_needed);
3019 #endif
3020 
3021 	/*
3022 	 * For ext4 we need to allow for up to a flex_bg worth of
3023 	 * inode tables of slack space so the resize operation can be
3024 	 * guaranteed to finish.
3025 	 */
3026 	flex_groups = groups;
3027 	if (ext2fs_has_feature_flex_bg(fs->super)) {
3028 		dgrp_t remainder = groups & (flexbg_size - 1);
3029 
3030 		flex_groups += flexbg_size - remainder;
3031 		if (flex_groups > fs->group_desc_count)
3032 			flex_groups = fs->group_desc_count;
3033 	}
3034 
3035 	/*
3036 	 * figure out how many data blocks we have given the number of groups
3037 	 * we need for our inodes
3038 	 */
3039 	data_blocks = EXT2_GROUPS_TO_BLOCKS(fs->super, groups);
3040 	last_start = 0;
3041 	for (grp = 0; grp < flex_groups; grp++) {
3042 		overhead = calc_group_overhead(fs, grp, old_desc_blocks);
3043 
3044 		/*
3045 		 * we want to keep track of how much data we can store in
3046 		 * the groups leading up to the last group so we can determine
3047 		 * how big the last group needs to be
3048 		 */
3049 		if (grp < (groups - 1))
3050 			last_start += EXT2_BLOCKS_PER_GROUP(fs->super) -
3051 				overhead;
3052 
3053 		if (data_blocks > overhead)
3054 			data_blocks -= overhead;
3055 		else
3056 			data_blocks = 0;
3057 	}
3058 #ifdef RESIZE2FS_DEBUG
3059 	if (flags & RESIZE_DEBUG_MIN_CALC)
3060 		printf("With %d group(s), we have %llu blocks available.\n",
3061 		       groups, (unsigned long long) data_blocks);
3062 #endif
3063 
3064 	/*
3065 	 * if we need more group descriptors in order to accommodate our data
3066 	 * then we need to add them here
3067 	 */
3068 	blks_needed = data_needed;
3069 	while (blks_needed > data_blocks) {
3070 		blk64_t remainder = blks_needed - data_blocks;
3071 		dgrp_t extra_grps;
3072 
3073 		/* figure out how many more groups we need for the data */
3074 		extra_grps = ext2fs_div64_ceil(remainder,
3075 					       EXT2_BLOCKS_PER_GROUP(fs->super));
3076 
3077 		data_blocks += EXT2_GROUPS_TO_BLOCKS(fs->super, extra_grps);
3078 
3079 		/* ok we have to account for the last group */
3080 		overhead = calc_group_overhead(fs, groups-1, old_desc_blocks);
3081 		last_start += EXT2_BLOCKS_PER_GROUP(fs->super) - overhead;
3082 
3083 		grp = flex_groups;
3084 		groups += extra_grps;
3085 		if (!ext2fs_has_feature_flex_bg(fs->super))
3086 			flex_groups = groups;
3087 		else if (groups > flex_groups) {
3088 			dgrp_t r = groups & (flexbg_size - 1);
3089 
3090 			flex_groups = groups + flexbg_size - r;
3091 			if (flex_groups > fs->group_desc_count)
3092 				flex_groups = fs->group_desc_count;
3093 		}
3094 
3095 		for (; grp < flex_groups; grp++) {
3096 			overhead = calc_group_overhead(fs, grp,
3097 						       old_desc_blocks);
3098 
3099 			/*
3100 			 * again, we need to see how much data we cram into
3101 			 * all of the groups leading up to the last group
3102 			 */
3103 			if (grp < groups - 1)
3104 				last_start += EXT2_BLOCKS_PER_GROUP(fs->super)
3105 					- overhead;
3106 
3107 			data_blocks -= overhead;
3108 		}
3109 
3110 #ifdef RESIZE2FS_DEBUG
3111 		if (flags & RESIZE_DEBUG_MIN_CALC)
3112 			printf("Added %d extra group(s), "
3113 			       "blks_needed %llu, data_blocks %llu, "
3114 			       "last_start %llu\n", extra_grps,
3115 			       (unsigned long long) blks_needed,
3116 			       (unsigned long long) data_blocks,
3117 			       (unsigned long long) last_start);
3118 #endif
3119 	}
3120 
3121 	/* now for the fun voodoo */
3122 	grp = groups - 1;
3123 	if (ext2fs_has_feature_flex_bg(fs->super) &&
3124 	    (grp & ~(flexbg_size - 1)) == 0)
3125 		grp = grp & ~(flexbg_size - 1);
3126 	overhead = 0;
3127 	for (; grp < flex_groups; grp++)
3128 		overhead += calc_group_overhead(fs, grp, old_desc_blocks);
3129 
3130 #ifdef RESIZE2FS_DEBUG
3131 	if (flags & RESIZE_DEBUG_MIN_CALC)
3132 		printf("Last group's overhead is %llu\n",
3133 		       (unsigned long long) overhead);
3134 #endif
3135 
3136 	/*
3137 	 * if this is the case then the last group is going to have data in it
3138 	 * so we need to adjust the size of the last group accordingly
3139 	 */
3140 	if (last_start < blks_needed) {
3141 		blk64_t remainder = blks_needed - last_start;
3142 
3143 #ifdef RESIZE2FS_DEBUG
3144 		if (flags & RESIZE_DEBUG_MIN_CALC)
3145 			printf("Need %llu data blocks in last group\n",
3146 			       (unsigned long long) remainder);
3147 #endif
3148 		/*
3149 		 * 50 is a magic number that mkfs/resize uses to see if its
3150 		 * even worth making/resizing the fs.  basically you need to
3151 		 * have at least 50 blocks in addition to the blocks needed
3152 		 * for the metadata in the last group
3153 		 */
3154 		if (remainder > 50)
3155 			overhead += remainder;
3156 		else
3157 			overhead += 50;
3158 	} else
3159 		overhead += 50;
3160 
3161 	overhead += fs->super->s_first_data_block;
3162 #ifdef RESIZE2FS_DEBUG
3163 	if (flags & RESIZE_DEBUG_MIN_CALC)
3164 		printf("Final size of last group is %llu\n",
3165 		       (unsigned long long) overhead);
3166 #endif
3167 
3168 	/* Add extra slack for bigalloc file systems */
3169 	if (EXT2FS_CLUSTER_RATIO(fs) > 1)
3170 		overhead += EXT2FS_CLUSTER_RATIO(fs) * 2;
3171 
3172 	/*
3173 	 * since our last group doesn't have to be BLOCKS_PER_GROUP
3174 	 * large, we only do groups-1, and then add the number of
3175 	 * blocks needed to handle the group descriptor metadata+data
3176 	 * that we need
3177 	 */
3178 	blks_needed = EXT2_GROUPS_TO_BLOCKS(fs->super, groups - 1);
3179 	blks_needed += overhead;
3180 
3181 	/*
3182 	 * Make sure blks_needed covers the end of the inode table in
3183 	 * the last block group.
3184 	 */
3185 	overhead = ext2fs_inode_table_loc(fs, groups-1) +
3186 		fs->inode_blocks_per_group;
3187 	if (blks_needed < overhead)
3188 		blks_needed = overhead;
3189 
3190 #ifdef RESIZE2FS_DEBUG
3191 	if (flags & RESIZE_DEBUG_MIN_CALC)
3192 		printf("Estimated blocks needed: %llu\n",
3193 		       (unsigned long long) blks_needed);
3194 #endif
3195 
3196 	/*
3197 	 * If at this point we've already added up more "needed" than
3198 	 * the current size, just return current size as minimum.
3199 	 */
3200 	if (blks_needed >= ext2fs_blocks_count(fs->super))
3201 		return ext2fs_blocks_count(fs->super);
3202 	/*
3203 	 * We need to reserve a few extra blocks if extents are
3204 	 * enabled, in case we need to grow the extent tree.  The more
3205 	 * we shrink the file system, the more space we need.
3206 	 *
3207 	 * The absolute worst case is every single data block is in
3208 	 * the part of the file system that needs to be evacuated,
3209 	 * with each data block needs to be in its own extent, and
3210 	 * with each inode needing at least one extent block.
3211 	 */
3212 	if (ext2fs_has_feature_extents(fs->super)) {
3213 		blk64_t safe_margin = (ext2fs_blocks_count(fs->super) -
3214 				       blks_needed)/500;
3215 		unsigned int exts_per_blk = (fs->blocksize /
3216 					     sizeof(struct ext3_extent)) - 1;
3217 		blk64_t worst_case = ((data_needed + exts_per_blk - 1) /
3218 				      exts_per_blk);
3219 
3220 		if (worst_case < inode_count)
3221 			worst_case = inode_count;
3222 
3223 		if (safe_margin > worst_case)
3224 			safe_margin = worst_case;
3225 
3226 #ifdef RESIZE2FS_DEBUG
3227 		if (flags & RESIZE_DEBUG_MIN_CALC)
3228 			printf("Extents safety margin: %llu\n",
3229 			       (unsigned long long) safe_margin);
3230 #endif
3231 		blks_needed += safe_margin;
3232 	}
3233 
3234 	return blks_needed;
3235 }
3236