e2image.c revision d1154eb460efe588eaed3d439c1caaca149fa362
1/*
2 * e2image.c --- Program which writes an image file backing up
3 * critical metadata for the filesystem.
4 *
5 * Copyright 2000, 2001 by Theodore Ts'o.
6 *
7 * %Begin-Header%
8 * This file may be redistributed under the terms of the GNU Public
9 * License.
10 * %End-Header%
11 */
12
13#define _LARGEFILE_SOURCE
14#define _LARGEFILE64_SOURCE
15
16#include "config.h"
17#include <fcntl.h>
18#include <grp.h>
19#ifdef HAVE_GETOPT_H
20#include <getopt.h>
21#else
22extern char *optarg;
23extern int optind;
24#endif
25#include <pwd.h>
26#include <stdio.h>
27#ifdef HAVE_STDLIB_H
28#include <stdlib.h>
29#endif
30#include <string.h>
31#include <time.h>
32#include <unistd.h>
33#include <fcntl.h>
34#include <errno.h>
35#include <sys/stat.h>
36#include <sys/types.h>
37#include <assert.h>
38
39#include "ext2fs/ext2_fs.h"
40#include "ext2fs/ext2fs.h"
41#include "et/com_err.h"
42#include "uuid/uuid.h"
43#include "e2p/e2p.h"
44#include "ext2fs/e2image.h"
45#include "ext2fs/qcow2.h"
46
47#include "../version.h"
48#include "nls-enable.h"
49
50#define QCOW_OFLAG_COPIED     (1LL << 63)
51
52
53const char * program_name = "e2image";
54char * device_name = NULL;
55
56static void lseek_error_and_exit(int errnum)
57{
58	perror("seek");
59	exit(1);
60}
61
62static blk64_t align_offset(blk64_t offset, int n)
63{
64	return (offset + n - 1) & ~(n - 1);
65}
66
67static int get_bits_from_size(size_t size)
68{
69	int res = 0;
70
71	if (size == 0)
72		return -1;
73
74	while (size != 1) {
75		/* Not a power of two */
76		if (size & 1)
77			return -1;
78
79		size >>= 1;
80		res++;
81	}
82	return res;
83}
84
85static void usage(void)
86{
87	fprintf(stderr, _("Usage: %s [-rsIQ] device image_file\n"),
88		program_name);
89	exit (1);
90}
91
92static void generic_write(int fd, void *buf, int blocksize, blk64_t block)
93{
94	int count, free_buf = 0;
95	errcode_t err;
96
97	if (!blocksize)
98		return;
99
100	if (!buf) {
101		free_buf = 1;
102		err = ext2fs_get_arrayzero(1, blocksize, &buf);
103		if (err) {
104			com_err(program_name, err, "while allocating buffer");
105			exit(1);
106		}
107	}
108
109	count = write(fd, buf, blocksize);
110	if (count != blocksize) {
111		if (count == -1)
112			err = errno;
113		else
114			err = 0;
115
116		if (block)
117			com_err(program_name, err, "error writing block %llu",
118				block);
119		else
120			com_err(program_name, err, "error in write()");
121
122		exit(1);
123	}
124	if (free_buf)
125		ext2fs_free_mem(&buf);
126}
127
128static void write_header(int fd, void *hdr, int hdr_size, int wrt_size)
129{
130	char *header_buf;
131	int ret;
132
133	/* Sanity check */
134	if (hdr_size > wrt_size) {
135		fprintf(stderr, _("Error: header size is bigger than "
136				  "wrt_size\n"));
137	}
138
139	ret = ext2fs_get_mem(wrt_size, &header_buf);
140	if (ret) {
141		fputs(_("Couldn't allocate header buffer\n"), stderr);
142		exit(1);
143	}
144
145	if (ext2fs_llseek(fd, 0, SEEK_SET) < 0) {
146		perror("ext2fs_llseek while writing header");
147		exit(1);
148	}
149	memset(header_buf, 0, wrt_size);
150
151	if (hdr)
152		memcpy(header_buf, hdr, hdr_size);
153
154	generic_write(fd, header_buf, wrt_size, 0);
155
156	ext2fs_free_mem(&header_buf);
157}
158
159static void write_image_file(ext2_filsys fs, int fd)
160{
161	struct ext2_image_hdr	hdr;
162	struct stat		st;
163	errcode_t		retval;
164
165	write_header(fd, NULL, fs->blocksize, fs->blocksize);
166	memset(&hdr, 0, sizeof(struct ext2_image_hdr));
167
168	hdr.offset_super = ext2fs_llseek(fd, 0, SEEK_CUR);
169	retval = ext2fs_image_super_write(fs, fd, 0);
170	if (retval) {
171		com_err(program_name, retval, _("while writing superblock"));
172		exit(1);
173	}
174
175	hdr.offset_inode = ext2fs_llseek(fd, 0, SEEK_CUR);
176	retval = ext2fs_image_inode_write(fs, fd,
177				  (fd != 1) ? IMAGER_FLAG_SPARSEWRITE : 0);
178	if (retval) {
179		com_err(program_name, retval, _("while writing inode table"));
180		exit(1);
181	}
182
183	hdr.offset_blockmap = ext2fs_llseek(fd, 0, SEEK_CUR);
184	retval = ext2fs_image_bitmap_write(fs, fd, 0);
185	if (retval) {
186		com_err(program_name, retval, _("while writing block bitmap"));
187		exit(1);
188	}
189
190	hdr.offset_inodemap = ext2fs_llseek(fd, 0, SEEK_CUR);
191	retval = ext2fs_image_bitmap_write(fs, fd, IMAGER_FLAG_INODEMAP);
192	if (retval) {
193		com_err(program_name, retval, _("while writing inode bitmap"));
194		exit(1);
195	}
196
197	hdr.magic_number = EXT2_ET_MAGIC_E2IMAGE;
198	strcpy(hdr.magic_descriptor, "Ext2 Image 1.0");
199	gethostname(hdr.fs_hostname, sizeof(hdr.fs_hostname));
200	strncpy(hdr.fs_device_name, device_name, sizeof(hdr.fs_device_name)-1);
201	hdr.fs_device_name[sizeof(hdr.fs_device_name) - 1] = 0;
202	hdr.fs_blocksize = fs->blocksize;
203
204	if (stat(device_name, &st) == 0)
205		hdr.fs_device = st.st_rdev;
206
207	if (fstat(fd, &st) == 0) {
208		hdr.image_device = st.st_dev;
209		hdr.image_inode = st.st_ino;
210	}
211	memcpy(hdr.fs_uuid, fs->super->s_uuid, sizeof(hdr.fs_uuid));
212
213	hdr.image_time = time(0);
214	write_header(fd, &hdr, fs->blocksize, fs->blocksize);
215}
216
217/*
218 * These set of functions are used to write a RAW image file.
219 */
220ext2fs_block_bitmap meta_block_map;
221ext2fs_block_bitmap scramble_block_map;	/* Directory blocks to be scrambled */
222blk64_t meta_blocks_count;
223
224struct process_block_struct {
225	ext2_ino_t	ino;
226	int		is_dir;
227};
228
229/*
230 * These subroutines short circuits ext2fs_get_blocks and
231 * ext2fs_check_directory; we use them since we already have the inode
232 * structure, so there's no point in letting the ext2fs library read
233 * the inode again.
234 */
235static ino_t stashed_ino = 0;
236static struct ext2_inode *stashed_inode;
237
238static errcode_t meta_get_blocks(ext2_filsys fs EXT2FS_ATTR((unused)),
239				 ext2_ino_t ino,
240				 blk_t *blocks)
241{
242	int	i;
243
244	if ((ino != stashed_ino) || !stashed_inode)
245		return EXT2_ET_CALLBACK_NOTHANDLED;
246
247	for (i=0; i < EXT2_N_BLOCKS; i++)
248		blocks[i] = stashed_inode->i_block[i];
249	return 0;
250}
251
252static errcode_t meta_check_directory(ext2_filsys fs EXT2FS_ATTR((unused)),
253				      ext2_ino_t ino)
254{
255	if ((ino != stashed_ino) || !stashed_inode)
256		return EXT2_ET_CALLBACK_NOTHANDLED;
257
258	if (!LINUX_S_ISDIR(stashed_inode->i_mode))
259		return EXT2_ET_NO_DIRECTORY;
260	return 0;
261}
262
263static errcode_t meta_read_inode(ext2_filsys fs EXT2FS_ATTR((unused)),
264				 ext2_ino_t ino,
265				 struct ext2_inode *inode)
266{
267	if ((ino != stashed_ino) || !stashed_inode)
268		return EXT2_ET_CALLBACK_NOTHANDLED;
269	*inode = *stashed_inode;
270	return 0;
271}
272
273static void use_inode_shortcuts(ext2_filsys fs, int bool)
274{
275	if (bool) {
276		fs->get_blocks = meta_get_blocks;
277		fs->check_directory = meta_check_directory;
278		fs->read_inode = meta_read_inode;
279		stashed_ino = 0;
280	} else {
281		fs->get_blocks = 0;
282		fs->check_directory = 0;
283		fs->read_inode = 0;
284	}
285}
286
287static int process_dir_block(ext2_filsys fs EXT2FS_ATTR((unused)),
288			     blk64_t *block_nr,
289			     e2_blkcnt_t blockcnt EXT2FS_ATTR((unused)),
290			     blk64_t ref_block EXT2FS_ATTR((unused)),
291			     int ref_offset EXT2FS_ATTR((unused)),
292			     void *priv_data EXT2FS_ATTR((unused)))
293{
294	struct process_block_struct *p;
295
296	p = (struct process_block_struct *) priv_data;
297
298	ext2fs_mark_block_bitmap2(meta_block_map, *block_nr);
299	meta_blocks_count++;
300	if (scramble_block_map && p->is_dir && blockcnt >= 0)
301		ext2fs_mark_block_bitmap2(scramble_block_map, *block_nr);
302	return 0;
303}
304
305static int process_file_block(ext2_filsys fs EXT2FS_ATTR((unused)),
306			      blk64_t *block_nr,
307			      e2_blkcnt_t blockcnt,
308			      blk64_t ref_block EXT2FS_ATTR((unused)),
309			      int ref_offset EXT2FS_ATTR((unused)),
310			      void *priv_data EXT2FS_ATTR((unused)))
311{
312	if (blockcnt < 0) {
313		ext2fs_mark_block_bitmap2(meta_block_map, *block_nr);
314		meta_blocks_count++;
315	}
316	return 0;
317}
318
319static void mark_table_blocks(ext2_filsys fs)
320{
321	blk64_t	first_block, b;
322	unsigned int	i,j;
323
324	first_block = fs->super->s_first_data_block;
325	/*
326	 * Mark primary superblock
327	 */
328	ext2fs_mark_block_bitmap2(meta_block_map, first_block);
329	meta_blocks_count++;
330
331	/*
332	 * Mark the primary superblock descriptors
333	 */
334	for (j = 0; j < fs->desc_blocks; j++) {
335		ext2fs_mark_block_bitmap2(meta_block_map,
336			 ext2fs_descriptor_block_loc2(fs, first_block, j));
337	}
338	meta_blocks_count += fs->desc_blocks;
339
340	for (i = 0; i < fs->group_desc_count; i++) {
341		/*
342		 * Mark the blocks used for the inode table
343		 */
344		if (ext2fs_inode_table_loc(fs, i)) {
345			for (j = 0, b = ext2fs_inode_table_loc(fs, i);
346			     j < (unsigned) fs->inode_blocks_per_group;
347			     j++, b++)
348				ext2fs_mark_block_bitmap2(meta_block_map, b);
349			meta_blocks_count += fs->inode_blocks_per_group;
350		}
351
352		/*
353		 * Mark block used for the block bitmap
354		 */
355		if (ext2fs_block_bitmap_loc(fs, i)) {
356			ext2fs_mark_block_bitmap2(meta_block_map,
357				     ext2fs_block_bitmap_loc(fs, i));
358			meta_blocks_count++;
359		}
360
361		/*
362		 * Mark block used for the inode bitmap
363		 */
364		if (ext2fs_inode_bitmap_loc(fs, i)) {
365			ext2fs_mark_block_bitmap2(meta_block_map,
366				 ext2fs_inode_bitmap_loc(fs, i));
367			meta_blocks_count++;
368		}
369	}
370}
371
372/*
373 * This function returns 1 if the specified block is all zeros
374 */
375static int check_zero_block(char *buf, int blocksize)
376{
377	char	*cp = buf;
378	int	left = blocksize;
379
380	while (left > 0) {
381		if (*cp++)
382			return 0;
383		left--;
384	}
385	return 1;
386}
387
388static void write_block(int fd, char *buf, int sparse_offset,
389			int blocksize, blk64_t block)
390{
391	ext2_loff_t	ret = 0;
392
393	if (sparse_offset)
394		ret = ext2fs_llseek(fd, sparse_offset, SEEK_CUR);
395
396	if (ret < 0)
397		lseek_error_and_exit(errno);
398	generic_write(fd, buf, blocksize, block);
399}
400
401int name_id[256];
402
403#define EXT4_MAX_REC_LEN		((1<<16)-1)
404
405static void scramble_dir_block(ext2_filsys fs, blk64_t blk, char *buf)
406{
407	char *p, *end, *cp;
408	struct ext2_dir_entry_2 *dirent;
409	unsigned int rec_len;
410	int id, len;
411
412	end = buf + fs->blocksize;
413	for (p = buf; p < end-8; p += rec_len) {
414		dirent = (struct ext2_dir_entry_2 *) p;
415		rec_len = dirent->rec_len;
416#ifdef WORDS_BIGENDIAN
417		rec_len = ext2fs_swab16(rec_len);
418#endif
419		if (rec_len == EXT4_MAX_REC_LEN || rec_len == 0)
420			rec_len = fs->blocksize;
421		else
422			rec_len = (rec_len & 65532) | ((rec_len & 3) << 16);
423#if 0
424		printf("rec_len = %d, name_len = %d\n", rec_len, dirent->name_len);
425#endif
426		if (rec_len < 8 || (rec_len % 4) ||
427		    (p+rec_len > end)) {
428			printf("Corrupt directory block %lu: "
429			       "bad rec_len (%d)\n", (unsigned long) blk,
430			       rec_len);
431			rec_len = end - p;
432			(void) ext2fs_set_rec_len(fs, rec_len,
433					(struct ext2_dir_entry *) dirent);
434#ifdef WORDS_BIGENDIAN
435			dirent->rec_len = ext2fs_swab16(dirent->rec_len);
436#endif
437			continue;
438		}
439		if (dirent->name_len + 8 > rec_len) {
440			printf("Corrupt directory block %lu: "
441			       "bad name_len (%d)\n", (unsigned long) blk,
442			       dirent->name_len);
443			dirent->name_len = rec_len - 8;
444			continue;
445		}
446		cp = p+8;
447		len = rec_len - dirent->name_len - 8;
448		if (len > 0)
449			memset(cp+dirent->name_len, 0, len);
450		if (dirent->name_len==1 && cp[0] == '.')
451			continue;
452		if (dirent->name_len==2 && cp[0] == '.' && cp[1] == '.')
453			continue;
454
455		memset(cp, 'A', dirent->name_len);
456		len = dirent->name_len;
457		id = name_id[len]++;
458		while ((len > 0) && (id > 0)) {
459			*cp += id % 26;
460			id = id / 26;
461			cp++;
462			len--;
463		}
464	}
465}
466
467static void output_meta_data_blocks(ext2_filsys fs, int fd)
468{
469	errcode_t	retval;
470	blk64_t		blk;
471	char		*buf, *zero_buf;
472	int		sparse = 0;
473
474	retval = ext2fs_get_mem(fs->blocksize, &buf);
475	if (retval) {
476		com_err(program_name, retval, "while allocating buffer");
477		exit(1);
478	}
479	retval = ext2fs_get_memzero(fs->blocksize, &zero_buf);
480	if (retval) {
481		com_err(program_name, retval, "while allocating buffer");
482		exit(1);
483	}
484	for (blk = 0; blk < ext2fs_blocks_count(fs->super); blk++) {
485		if ((blk >= fs->super->s_first_data_block) &&
486		    ext2fs_test_block_bitmap2(meta_block_map, blk)) {
487			retval = io_channel_read_blk64(fs->io, blk, 1, buf);
488			if (retval) {
489				com_err(program_name, retval,
490					"error reading block %llu", blk);
491			}
492			if (scramble_block_map &&
493			    ext2fs_test_block_bitmap2(scramble_block_map, blk))
494				scramble_dir_block(fs, blk, buf);
495			if ((fd != 1) && check_zero_block(buf, fs->blocksize))
496				goto sparse_write;
497			write_block(fd, buf, sparse, fs->blocksize, blk);
498			sparse = 0;
499		} else {
500		sparse_write:
501			if (fd == 1) {
502				write_block(fd, zero_buf, 0,
503					    fs->blocksize, blk);
504				continue;
505			}
506			sparse += fs->blocksize;
507			if (sparse >= 1024*1024) {
508
509				write_block(fd, 0, sparse, 0, 0);
510				sparse = 0;
511			}
512		}
513	}
514	if (sparse)
515		write_block(fd, zero_buf, sparse-1, 1, -1);
516	ext2fs_free_mem(&zero_buf);
517	ext2fs_free_mem(&buf);
518}
519
520static void init_l1_table(struct ext2_super_block *sb,
521			  struct ext2_qcow2_image *image)
522{
523	__u64 *l1_table;
524	errcode_t ret;
525
526	ret = ext2fs_get_arrayzero(image->l1_size, sizeof(__u64), &l1_table);
527	if (ret) {
528		com_err(program_name, ret, "while allocating l1 table");
529		exit(1);
530	}
531
532	image->l1_table = l1_table;
533}
534
535static void init_l2_cache(struct ext2_qcow2_image *image)
536{
537	unsigned int count, i;
538	struct ext2_qcow2_l2_cache *cache;
539	struct ext2_qcow2_l2_table *table;
540	errcode_t ret;
541
542	ret = ext2fs_get_arrayzero(1, sizeof(struct ext2_qcow2_l2_cache),
543				   &cache);
544	if (ret)
545		goto alloc_err;
546
547	count = (image->l1_size > L2_CACHE_PREALLOC) ? L2_CACHE_PREALLOC :
548		 image->l1_size;
549
550	cache->count = count;
551	cache->free = count;
552	cache->next_offset = image->l2_offset;
553
554	for (i = 0; i < count; i++) {
555		ret = ext2fs_get_arrayzero(1,
556				sizeof(struct ext2_qcow2_l2_table), &table);
557		if (ret)
558			goto alloc_err;
559
560		ret = ext2fs_get_arrayzero(image->l2_size,
561						   sizeof(__u64), &table->data);
562		if (ret)
563			goto alloc_err;
564
565		table->next = cache->free_head;
566		cache->free_head = table;
567	}
568
569	image->l2_cache = cache;
570	return;
571
572alloc_err:
573	com_err(program_name, ret, "while allocating l2 cache");
574	exit(1);
575}
576
577static void put_l2_cache(struct ext2_qcow2_image *image)
578{
579	struct ext2_qcow2_l2_cache *cache = image->l2_cache;
580	struct ext2_qcow2_l2_table *tmp, *table;
581
582	if (!cache)
583		return;
584
585	table = cache->free_head;
586	cache->free_head = NULL;
587again:
588	while (table) {
589		tmp = table;
590		table = table->next;
591		ext2fs_free_mem(&tmp->data);
592		ext2fs_free_mem(&tmp);
593	}
594
595	if (cache->free != cache->count) {
596		fprintf(stderr, "Warning: There are still tables in the "
597				"cache while putting the cache, data will "
598				"be lost so the image may not be valid.\n");
599		table = cache->used_head;
600		cache->used_head = NULL;
601		goto again;
602	}
603
604	ext2fs_free_mem(&cache);
605}
606
607static int init_refcount(struct ext2_qcow2_image *img, blk64_t table_offset)
608{
609	struct	ext2_qcow2_refcount	*ref;
610	blk64_t table_clusters;
611	errcode_t ret;
612
613	ref = &(img->refcount);
614
615	/*
616	 * One refcount block addresses 2048 clusters, one refcount table
617	 * addresses cluster/sizeof(__u64) refcount blocks, and we need
618	 * to address meta_blocks_count clusters + qcow2 metadata clusters
619	 * in the worst case.
620	 */
621	table_clusters = meta_blocks_count + (table_offset >>
622					      img->cluster_bits);
623	table_clusters >>= (img->cluster_bits + 6 - 1);
624	table_clusters = (table_clusters == 0) ? 1 : table_clusters;
625
626	ref->refcount_table_offset = table_offset;
627	ref->refcount_table_clusters = table_clusters;
628	ref->refcount_table_index = 0;
629	ref->refcount_block_index = 0;
630
631	/* Allocate refcount table */
632	ret = ext2fs_get_arrayzero(ref->refcount_table_clusters,
633				   img->cluster_size, &ref->refcount_table);
634	if (ret)
635		return ret;
636
637	/* Allocate refcount block */
638	ret = ext2fs_get_arrayzero(1, img->cluster_size, &ref->refcount_block);
639	if (ret)
640		ext2fs_free_mem(&ref->refcount_table);
641
642	return ret;
643}
644
645static int initialize_qcow2_image(int fd, ext2_filsys fs,
646			    struct ext2_qcow2_image *image)
647{
648	struct ext2_qcow2_hdr *header;
649	blk64_t total_size, offset;
650	int shift, l2_bits, header_size, l1_size, ret;
651	int cluster_bits = get_bits_from_size(fs->blocksize);
652	struct ext2_super_block *sb = fs->super;
653
654	/* Allocate header */
655	ret = ext2fs_get_memzero(sizeof(struct ext2_qcow2_hdr), &header);
656	if (ret)
657		return ret;
658
659	total_size = ext2fs_blocks_count(sb) << cluster_bits;
660	image->cluster_size = fs->blocksize;
661	image->l2_size = 1 << (cluster_bits - 3);
662	image->cluster_bits = cluster_bits;
663	image->fd = fd;
664
665	header->magic = ext2fs_cpu_to_be32(QCOW_MAGIC);
666	header->version = ext2fs_cpu_to_be32(QCOW_VERSION);
667	header->size = ext2fs_cpu_to_be64(total_size);
668	header->cluster_bits = ext2fs_cpu_to_be32(cluster_bits);
669
670	header_size = (sizeof(struct ext2_qcow2_hdr) + 7) & ~7;
671	offset = align_offset(header_size, image->cluster_size);
672
673	header->l1_table_offset = ext2fs_cpu_to_be64(offset);
674	image->l1_offset = offset;
675
676	l2_bits = cluster_bits - 3;
677	shift = cluster_bits + l2_bits;
678	l1_size = ((total_size + (1LL << shift) - 1) >> shift);
679	header->l1_size = ext2fs_cpu_to_be32(l1_size);
680	image->l1_size = l1_size;
681
682	/* Make space for L1 table */
683	offset += align_offset(l1_size * sizeof(blk64_t), image->cluster_size);
684
685	/* Initialize refcounting */
686	ret = init_refcount(image, offset);
687	if (ret) {
688		ext2fs_free_mem(&header);
689		return ret;
690	}
691	header->refcount_table_offset = ext2fs_cpu_to_be64(offset);
692	header->refcount_table_clusters =
693		ext2fs_cpu_to_be32(image->refcount.refcount_table_clusters);
694	offset += image->cluster_size;
695	offset += image->refcount.refcount_table_clusters <<
696		image->cluster_bits;
697
698	/* Make space for L2 tables */
699	image->l2_offset = offset;
700	offset += image->cluster_size;
701
702	/* Make space for first refcount block */
703	image->refcount.refcount_block_offset = offset;
704
705	image->hdr = header;
706	/* Initialize l1 and l2 tables */
707	init_l1_table(sb, image);
708	init_l2_cache(image);
709
710	return 0;
711}
712
713static void free_qcow2_image(struct ext2_qcow2_image *img)
714{
715	if (!img)
716		return;
717
718	if (img->hdr)
719		ext2fs_free_mem(&img->hdr);
720
721	if (img->l1_table)
722		ext2fs_free_mem(&img->l1_table);
723
724	if (img->refcount.refcount_table)
725		ext2fs_free_mem(&img->refcount.refcount_table);
726	if (img->refcount.refcount_block)
727		ext2fs_free_mem(&img->refcount.refcount_block);
728
729	put_l2_cache(img);
730
731	ext2fs_free_mem(&img);
732}
733
734/**
735 * Put table from used list (used_head) into free list (free_head).
736 * l2_table is used to return pointer to the next used table (used_head).
737 */
738static void put_used_table(struct ext2_qcow2_image *img,
739			  struct ext2_qcow2_l2_table **l2_table)
740{
741	struct ext2_qcow2_l2_cache *cache = img->l2_cache;
742	struct ext2_qcow2_l2_table *table;
743
744	table = cache->used_head;
745	cache->used_head = table->next;
746
747	assert(table);
748	if (!table->next)
749		cache->used_tail = NULL;
750
751	/* Clean the table for case we will need to use it again */
752	memset(table->data, 0, img->cluster_size);
753	table->next = cache->free_head;
754	cache->free_head = table;
755
756	cache->free++;
757
758	*l2_table = cache->used_head;
759}
760
761static void flush_l2_cache(struct ext2_qcow2_image *image)
762{
763	blk64_t seek = 0;
764	ext2_loff_t offset;
765	struct ext2_qcow2_l2_cache *cache = image->l2_cache;
766	struct ext2_qcow2_l2_table *table = cache->used_head;
767	int fd = image->fd;
768
769	/* Store current position */
770	if ((offset = ext2fs_llseek(fd, 0, SEEK_CUR)) < 0)
771		lseek_error_and_exit(errno);
772
773	assert(table);
774	while (cache->free < cache->count) {
775		if (seek != table->offset) {
776			if (ext2fs_llseek(fd, table->offset, SEEK_SET) < 0)
777				lseek_error_and_exit(errno);
778			seek = table->offset;
779		}
780
781		generic_write(fd, (char *)table->data, image->cluster_size , 0);
782		put_used_table(image, &table);
783		seek += image->cluster_size;
784	}
785
786	/* Restore previous position */
787	if (ext2fs_llseek(fd, offset, SEEK_SET) < 0)
788		lseek_error_and_exit(errno);
789}
790
791/**
792 * Get first free table (from free_head) and put it into tail of used list
793 * (to used_tail).
794 * l2_table is used to return pointer to moved table.
795 * Returns 1 if the cache is full, 0 otherwise.
796 */
797static void get_free_table(struct ext2_qcow2_image *image,
798			  struct ext2_qcow2_l2_table **l2_table)
799{
800	struct ext2_qcow2_l2_table *table;
801	struct ext2_qcow2_l2_cache *cache = image->l2_cache;
802
803	if (0 == cache->free)
804		flush_l2_cache(image);
805
806	table = cache->free_head;
807	assert(table);
808	cache->free_head = table->next;
809
810	if (cache->used_tail)
811		cache->used_tail->next = table;
812	else
813		/* First item in the used list */
814		cache->used_head = table;
815
816	cache->used_tail = table;
817	cache->free--;
818
819	*l2_table = table;
820}
821
822static int add_l2_item(struct ext2_qcow2_image *img, blk64_t blk,
823		       blk64_t data, blk64_t next)
824{
825	struct ext2_qcow2_l2_cache *cache = img->l2_cache;
826	struct ext2_qcow2_l2_table *table = cache->used_tail;
827	blk64_t l1_index = blk / img->l2_size;
828	blk64_t l2_index = blk & (img->l2_size - 1);
829	int ret = 0;
830
831	/*
832	 * Need to create new table if it does not exist,
833	 * or if it is full
834	 */
835	if (!table || (table->l1_index != l1_index)) {
836		get_free_table(img, &table);
837		table->l1_index = l1_index;
838		table->offset = cache->next_offset;
839		cache->next_offset = next;
840		img->l1_table[l1_index] =
841			ext2fs_cpu_to_be64(table->offset | QCOW_OFLAG_COPIED);
842		ret++;
843	}
844
845	table->data[l2_index] = ext2fs_cpu_to_be64(data | QCOW_OFLAG_COPIED);
846	return ret;
847}
848
849static int update_refcount(int fd, struct ext2_qcow2_image *img,
850			   blk64_t offset, blk64_t rfblk_pos)
851{
852	struct	ext2_qcow2_refcount	*ref;
853	__u32	table_index;
854	int ret = 0;
855
856	ref = &(img->refcount);
857	table_index = offset >> (2 * img->cluster_bits - 1);
858
859	/*
860	 * Need to create new refcount block when the offset addresses
861	 * another item in the refcount table
862	 */
863	if (table_index != ref->refcount_table_index) {
864
865		if (ext2fs_llseek(fd, ref->refcount_block_offset, SEEK_SET) < 0)
866			lseek_error_and_exit(errno);
867
868		generic_write(fd, (char *)ref->refcount_block,
869			      img->cluster_size, 0);
870		memset(ref->refcount_block, 0, img->cluster_size);
871
872		ref->refcount_table[ref->refcount_table_index] =
873			ext2fs_cpu_to_be64(ref->refcount_block_offset);
874		ref->refcount_block_offset = rfblk_pos;
875		ref->refcount_block_index = 0;
876		ref->refcount_table_index = table_index;
877		ret++;
878	}
879
880	/*
881	 * We are relying on the fact that we are creating the qcow2
882	 * image sequentially, hence we will always allocate refcount
883	 * block items sequentialy.
884	 */
885	ref->refcount_block[ref->refcount_block_index] = ext2fs_cpu_to_be16(1);
886	ref->refcount_block_index++;
887	return ret;
888}
889
890static int sync_refcount(int fd, struct ext2_qcow2_image *img)
891{
892	struct	ext2_qcow2_refcount	*ref;
893
894	ref = &(img->refcount);
895
896	ref->refcount_table[ref->refcount_table_index] =
897		ext2fs_cpu_to_be64(ref->refcount_block_offset);
898	if (ext2fs_llseek(fd, ref->refcount_table_offset, SEEK_SET) < 0)
899		lseek_error_and_exit(errno);
900	generic_write(fd, (char *)ref->refcount_table,
901		ref->refcount_table_clusters << img->cluster_bits, 0);
902
903	if (ext2fs_llseek(fd, ref->refcount_block_offset, SEEK_SET) < 0)
904		lseek_error_and_exit(errno);
905	generic_write(fd, (char *)ref->refcount_block, img->cluster_size, 0);
906	return 0;
907}
908
909static void output_qcow2_meta_data_blocks(ext2_filsys fs, int fd)
910{
911	errcode_t		retval;
912	blk64_t			blk, offset, size, end;
913	char			*buf;
914	struct ext2_qcow2_image	*img;
915	unsigned int		header_size;
916
917	/* allocate  struct ext2_qcow2_image */
918	retval = ext2fs_get_mem(sizeof(struct ext2_qcow2_image), &img);
919	if (retval) {
920		com_err(program_name, retval,
921			"while allocating ext2_qcow2_image");
922		exit(1);
923	}
924
925	retval = initialize_qcow2_image(fd, fs, img);
926	if (retval) {
927		com_err(program_name, retval,
928			"while initializing ext2_qcow2_image");
929		exit(1);
930	}
931	header_size = align_offset(sizeof(struct ext2_qcow2_hdr),
932				   img->cluster_size);
933	write_header(fd, img->hdr, sizeof(struct ext2_qcow2_hdr), header_size);
934
935	/* Refcount all qcow2 related metadata up to refcount_block_offset */
936	end = img->refcount.refcount_block_offset;
937	if (ext2fs_llseek(fd, end, SEEK_SET) < 0)
938		lseek_error_and_exit(errno);
939	blk = end + img->cluster_size;
940	for (offset = 0; offset <= end; offset += img->cluster_size) {
941		if (update_refcount(fd, img, offset, blk)) {
942			blk += img->cluster_size;
943			/*
944			 * If we create new refcount block, we need to refcount
945			 * it as well.
946			 */
947			end += img->cluster_size;
948		}
949	}
950	if (ext2fs_llseek(fd, offset, SEEK_SET) < 0)
951		lseek_error_and_exit(errno);
952
953	retval = ext2fs_get_mem(fs->blocksize, &buf);
954	if (retval) {
955		com_err(program_name, retval, "while allocating buffer");
956		exit(1);
957	}
958	/* Write qcow2 data blocks */
959	for (blk = 0; blk < ext2fs_blocks_count(fs->super); blk++) {
960		if ((blk >= fs->super->s_first_data_block) &&
961		    ext2fs_test_block_bitmap2(meta_block_map, blk)) {
962			retval = io_channel_read_blk64(fs->io, blk, 1, buf);
963			if (retval) {
964				com_err(program_name, retval,
965					"error reading block %llu", blk);
966				continue;
967			}
968			if (scramble_block_map &&
969			    ext2fs_test_block_bitmap2(scramble_block_map, blk))
970				scramble_dir_block(fs, blk, buf);
971			if (check_zero_block(buf, fs->blocksize))
972				continue;
973
974			if (update_refcount(fd, img, offset, offset)) {
975				/* Make space for another refcount block */
976				offset += img->cluster_size;
977				if (ext2fs_llseek(fd, offset, SEEK_SET) < 0)
978					lseek_error_and_exit(errno);
979				/*
980				 * We have created the new refcount block, this
981				 * means that we need to refcount it as well.
982				 * So the previous update_refcount refcounted
983				 * the block itself and now we are going to
984				 * create refcount for data. New refcount
985				 * block should not be created!
986				 */
987				if (update_refcount(fd, img, offset, offset)) {
988					fprintf(stderr, "Programming error: "
989						"multiple sequential refcount "
990						"blocks created!\n");
991					exit(1);
992				}
993			}
994
995			generic_write(fd, buf, fs->blocksize, 0);
996
997			if (add_l2_item(img, blk, offset,
998					offset + img->cluster_size)) {
999				offset += img->cluster_size;
1000				if (update_refcount(fd, img, offset,
1001					offset + img->cluster_size)) {
1002					offset += img->cluster_size;
1003					if (update_refcount(fd, img, offset,
1004							    offset)) {
1005						fprintf(stderr,
1006			"Programming error: multiple sequential refcount "
1007			"blocks created!\n");
1008						exit(1);
1009					}
1010				}
1011				offset += img->cluster_size;
1012				if (ext2fs_llseek(fd, offset, SEEK_SET) < 0)
1013					lseek_error_and_exit(errno);
1014				continue;
1015			}
1016
1017			offset += img->cluster_size;
1018		}
1019	}
1020	update_refcount(fd, img, offset, offset);
1021	flush_l2_cache(img);
1022	sync_refcount(fd, img);
1023
1024	/* Write l1_table*/
1025	if (ext2fs_llseek(fd, img->l1_offset, SEEK_SET) < 0)
1026		lseek_error_and_exit(errno);
1027	size = img->l1_size * sizeof(__u64);
1028	generic_write(fd, (char *)img->l1_table, size, 0);
1029
1030	ext2fs_free_mem(&buf);
1031	free_qcow2_image(img);
1032}
1033
1034static void write_raw_image_file(ext2_filsys fs, int fd, int type, int flags)
1035{
1036	struct process_block_struct	pb;
1037	struct ext2_inode		inode;
1038	ext2_inode_scan			scan;
1039	ext2_ino_t			ino;
1040	errcode_t			retval;
1041	char *				block_buf;
1042
1043	meta_blocks_count = 0;
1044	retval = ext2fs_allocate_block_bitmap(fs, "in-use block map",
1045					      &meta_block_map);
1046	if (retval) {
1047		com_err(program_name, retval, "while allocating block bitmap");
1048		exit(1);
1049	}
1050
1051	if (flags & E2IMAGE_SCRAMBLE_FLAG) {
1052		retval = ext2fs_allocate_block_bitmap(fs, "scramble block map",
1053						      &scramble_block_map);
1054		if (retval) {
1055			com_err(program_name, retval,
1056				"while allocating scramble block bitmap");
1057			exit(1);
1058		}
1059	}
1060
1061	mark_table_blocks(fs);
1062
1063	retval = ext2fs_open_inode_scan(fs, 0, &scan);
1064	if (retval) {
1065		com_err(program_name, retval, _("while opening inode scan"));
1066		exit(1);
1067	}
1068
1069	retval = ext2fs_get_mem(fs->blocksize * 3, &block_buf);
1070	if (retval) {
1071		com_err(program_name, 0, "Can't allocate block buffer");
1072		exit(1);
1073	}
1074
1075	use_inode_shortcuts(fs, 1);
1076	stashed_inode = &inode;
1077	while (1) {
1078		retval = ext2fs_get_next_inode(scan, &ino, &inode);
1079		if (retval == EXT2_ET_BAD_BLOCK_IN_INODE_TABLE)
1080			continue;
1081		if (retval) {
1082			com_err(program_name, retval,
1083				_("while getting next inode"));
1084			exit(1);
1085		}
1086		if (ino == 0)
1087			break;
1088		if (!inode.i_links_count)
1089			continue;
1090		if (ext2fs_file_acl_block(&inode)) {
1091			ext2fs_mark_block_bitmap2(meta_block_map,
1092						 ext2fs_file_acl_block(&inode));
1093			meta_blocks_count++;
1094		}
1095		if (!ext2fs_inode_has_valid_blocks(&inode))
1096			continue;
1097
1098		stashed_ino = ino;
1099		pb.ino = ino;
1100		pb.is_dir = LINUX_S_ISDIR(inode.i_mode);
1101		if (LINUX_S_ISDIR(inode.i_mode) ||
1102		    (LINUX_S_ISLNK(inode.i_mode) &&
1103		     ext2fs_inode_has_valid_blocks(&inode)) ||
1104		    ino == fs->super->s_journal_inum) {
1105			retval = ext2fs_block_iterate3(fs, ino,
1106					BLOCK_FLAG_READ_ONLY, block_buf,
1107					process_dir_block, &pb);
1108			if (retval) {
1109				com_err(program_name, retval,
1110					"while iterating over inode %u",
1111					ino);
1112				exit(1);
1113			}
1114		} else {
1115			if ((inode.i_flags & EXT4_EXTENTS_FL) ||
1116			    inode.i_block[EXT2_IND_BLOCK] ||
1117			    inode.i_block[EXT2_DIND_BLOCK] ||
1118			    inode.i_block[EXT2_TIND_BLOCK]) {
1119				retval = ext2fs_block_iterate3(fs,
1120				       ino, BLOCK_FLAG_READ_ONLY, block_buf,
1121				       process_file_block, &pb);
1122				if (retval) {
1123					com_err(program_name, retval,
1124					"while iterating over inode %u", ino);
1125					exit(1);
1126				}
1127			}
1128		}
1129	}
1130	use_inode_shortcuts(fs, 0);
1131
1132	if (type & E2IMAGE_QCOW2)
1133		output_qcow2_meta_data_blocks(fs, fd);
1134	else
1135		output_meta_data_blocks(fs, fd);
1136
1137	ext2fs_free_mem(&block_buf);
1138	ext2fs_close_inode_scan(scan);
1139	ext2fs_free_block_bitmap(meta_block_map);
1140	if (type & E2IMAGE_SCRAMBLE_FLAG)
1141		ext2fs_free_block_bitmap(scramble_block_map);
1142}
1143
1144static void install_image(char *device, char *image_fn, int type)
1145{
1146	errcode_t retval;
1147	ext2_filsys fs;
1148	int open_flag = EXT2_FLAG_IMAGE_FILE;
1149	int fd = 0;
1150	io_manager	io_ptr;
1151	io_channel	io;
1152
1153	if (type) {
1154		com_err(program_name, 0, "Raw and qcow2 images cannot"
1155			"be installed");
1156		exit(1);
1157	}
1158
1159#ifdef CONFIG_TESTIO_DEBUG
1160	if (getenv("TEST_IO_FLAGS") || getenv("TEST_IO_BLOCK")) {
1161		io_ptr = test_io_manager;
1162		test_io_backing_manager = unix_io_manager;
1163	} else
1164#endif
1165		io_ptr = unix_io_manager;
1166
1167	retval = ext2fs_open (image_fn, open_flag, 0, 0,
1168			      io_ptr, &fs);
1169        if (retval) {
1170		com_err (program_name, retval, _("while trying to open %s"),
1171			 image_fn);
1172		exit(1);
1173	}
1174
1175	retval = ext2fs_read_bitmaps (fs);
1176	if (retval) {
1177		com_err(program_name, retval, "error reading bitmaps");
1178		exit(1);
1179	}
1180
1181	fd = ext2fs_open_file(image_fn, O_RDONLY);
1182	if (fd < 0) {
1183		perror(image_fn);
1184		exit(1);
1185	}
1186
1187	retval = io_ptr->open(device, IO_FLAG_RW, &io);
1188	if (retval) {
1189		com_err(device, 0, "while opening device file");
1190		exit(1);
1191	}
1192
1193	ext2fs_rewrite_to_io(fs, io);
1194
1195	if (ext2fs_llseek(fd, fs->image_header->offset_inode, SEEK_SET) < 0) {
1196		perror("ext2fs_llseek");
1197		exit(1);
1198	}
1199
1200	retval = ext2fs_image_inode_read(fs, fd, 0);
1201	if (retval) {
1202		com_err(image_fn, 0, "while restoring the image table");
1203		exit(1);
1204	}
1205
1206	ext2fs_close (fs);
1207	exit (0);
1208}
1209
1210static struct ext2_qcow2_hdr *check_qcow2_image(int *fd, char *name)
1211{
1212
1213	*fd = ext2fs_open_file(name, O_RDONLY, 0600);
1214	if (*fd < 0)
1215		return NULL;
1216
1217	return qcow2_read_header(*fd);
1218}
1219
1220int main (int argc, char ** argv)
1221{
1222	int c;
1223	errcode_t retval;
1224	ext2_filsys fs;
1225	char *image_fn;
1226	struct ext2_qcow2_hdr *header = NULL;
1227	int open_flag = EXT2_FLAG_64BITS;
1228	int img_type = 0;
1229	int flags = 0;
1230	int qcow2_fd = 0;
1231	int fd = 0;
1232	int ret = 0;
1233
1234#ifdef ENABLE_NLS
1235	setlocale(LC_MESSAGES, "");
1236	setlocale(LC_CTYPE, "");
1237	bindtextdomain(NLS_CAT_NAME, LOCALEDIR);
1238	textdomain(NLS_CAT_NAME);
1239#endif
1240	fprintf (stderr, "e2image %s (%s)\n", E2FSPROGS_VERSION,
1241		 E2FSPROGS_DATE);
1242	if (argc && *argv)
1243		program_name = *argv;
1244	add_error_table(&et_ext2_error_table);
1245	while ((c = getopt(argc, argv, "rsIQ")) != EOF)
1246		switch (c) {
1247		case 'I':
1248			flags |= E2IMAGE_INSTALL_FLAG;
1249			break;
1250		case 'Q':
1251			if (img_type)
1252				usage();
1253			img_type |= E2IMAGE_QCOW2;
1254			break;
1255		case 'r':
1256			if (img_type)
1257				usage();
1258			img_type |= E2IMAGE_RAW;
1259			break;
1260		case 's':
1261			flags |= E2IMAGE_SCRAMBLE_FLAG;
1262			break;
1263		default:
1264			usage();
1265		}
1266	if (optind != argc - 2 )
1267		usage();
1268	device_name = argv[optind];
1269	image_fn = argv[optind+1];
1270
1271	if (flags & E2IMAGE_INSTALL_FLAG) {
1272		install_image(device_name, image_fn, img_type);
1273		exit (0);
1274	}
1275
1276	if (img_type & E2IMAGE_RAW) {
1277		header = check_qcow2_image(&qcow2_fd, device_name);
1278		if (header) {
1279			flags |= E2IMAGE_IS_QCOW2_FLAG;
1280			goto skip_device;
1281		}
1282	}
1283
1284	retval = ext2fs_open (device_name, open_flag, 0, 0,
1285			      unix_io_manager, &fs);
1286        if (retval) {
1287		com_err (program_name, retval, _("while trying to open %s"),
1288			 device_name);
1289		fputs(_("Couldn't find valid filesystem superblock.\n"), stdout);
1290		exit(1);
1291	}
1292
1293skip_device:
1294	if (strcmp(image_fn, "-") == 0)
1295		fd = 1;
1296	else {
1297		fd = ext2fs_open_file(image_fn, O_CREAT|O_TRUNC|O_WRONLY, 0600);
1298		if (fd < 0) {
1299			com_err(program_name, errno,
1300				_("while trying to open %s"), argv[optind+1]);
1301			exit(1);
1302		}
1303	}
1304
1305	if ((img_type & E2IMAGE_QCOW2) && (fd == 1)) {
1306		com_err(program_name, 0, "QCOW2 image can not be written to "
1307					 "the stdout!\n");
1308		exit(1);
1309	}
1310
1311	if (flags & E2IMAGE_IS_QCOW2_FLAG) {
1312		ret = qcow2_write_raw_image(qcow2_fd, fd, header);
1313		if (ret) {
1314			if (ret == -QCOW_COMPRESSED)
1315				fprintf(stderr, "Image (%s) is compressed\n",
1316					image_fn);
1317			if (ret == -QCOW_ENCRYPTED)
1318				fprintf(stderr, "Image (%s) is encrypted\n",
1319					image_fn);
1320			com_err(program_name, ret,
1321				_("while trying to convert qcow2 image"
1322				" (%s) into raw image (%s)"),
1323				device_name, image_fn);
1324		}
1325		goto out;
1326	}
1327
1328
1329	if (img_type)
1330		write_raw_image_file(fs, fd, img_type, flags);
1331	else
1332		write_image_file(fs, fd);
1333
1334	ext2fs_close (fs);
1335out:
1336	if (header)
1337		free(header);
1338	if (qcow2_fd)
1339		close(qcow2_fd);
1340	remove_error_table(&et_ext2_error_table);
1341	return ret;
1342}
1343