f9dd73465ceb34fcf106e38fecb3418f881903e9
[platform/upstream/btrfs-progs.git] / btrfs-convert.c
1 /*
2  * Copyright (C) 2007 Oracle.  All rights reserved.
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU General Public
6  * License v2 as published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope that it will be useful,
9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
11  * General Public License for more details.
12  *
13  * You should have received a copy of the GNU General Public
14  * License along with this program; if not, write to the
15  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16  * Boston, MA 021110-1307, USA.
17  */
18
19 #include "kerncompat.h"
20
21 #include <sys/ioctl.h>
22 #include <sys/mount.h>
23 #include <stdio.h>
24 #include <stdlib.h>
25 #include <sys/types.h>
26 #include <sys/stat.h>
27 #include <sys/acl.h>
28 #include <fcntl.h>
29 #include <unistd.h>
30 #include <uuid/uuid.h>
31 #include <linux/limits.h>
32 #include <getopt.h>
33
34 #include "ctree.h"
35 #include "disk-io.h"
36 #include "volumes.h"
37 #include "transaction.h"
38 #include "crc32c.h"
39 #include "utils.h"
40 #include "task-utils.h"
41 #include <ext2fs/ext2_fs.h>
42 #include <ext2fs/ext2fs.h>
43 #include <ext2fs/ext2_ext_attr.h>
44
45 #define INO_OFFSET (BTRFS_FIRST_FREE_OBJECTID - EXT2_ROOT_INO)
46 #define EXT2_IMAGE_SUBVOL_OBJECTID BTRFS_FIRST_FREE_OBJECTID
47
48 struct task_ctx {
49         uint32_t max_copy_inodes;
50         uint32_t cur_copy_inodes;
51         struct task_info *info;
52 };
53
54 static void *print_copied_inodes(void *p)
55 {
56         struct task_ctx *priv = p;
57         const char work_indicator[] = { '.', 'o', 'O', 'o' };
58         uint32_t count = 0;
59
60         task_period_start(priv->info, 1000 /* 1s */);
61         while (1) {
62                 count++;
63                 printf("copy inodes [%c] [%10d/%10d]\r",
64                        work_indicator[count % 4], priv->cur_copy_inodes,
65                        priv->max_copy_inodes);
66                 fflush(stdout);
67                 task_period_wait(priv->info);
68         }
69
70         return NULL;
71 }
72
73 static int after_copied_inodes(void *p)
74 {
75         struct task_ctx *priv = p;
76
77         printf("\n");
78         task_period_stop(priv->info);
79
80         return 0;
81 }
82
83 /*
84  * Open Ext2fs in readonly mode, read block allocation bitmap and
85  * inode bitmap into memory.
86  */
87 static int open_ext2fs(const char *name, ext2_filsys *ret_fs)
88 {
89         errcode_t ret;
90         ext2_filsys ext2_fs;
91         ext2_ino_t ino;
92         ret = ext2fs_open(name, 0, 0, 0, unix_io_manager, &ext2_fs);
93         if (ret) {
94                 fprintf(stderr, "ext2fs_open: %s\n", error_message(ret));
95                 goto fail;
96         }
97         ret = ext2fs_read_inode_bitmap(ext2_fs);
98         if (ret) {
99                 fprintf(stderr, "ext2fs_read_inode_bitmap: %s\n",
100                         error_message(ret));
101                 goto fail;
102         }
103         ret = ext2fs_read_block_bitmap(ext2_fs);
104         if (ret) {
105                 fprintf(stderr, "ext2fs_read_block_bitmap: %s\n",
106                         error_message(ret));
107                 goto fail;
108         }
109         /*
110          * search each block group for a free inode. this set up
111          * uninit block/inode bitmaps appropriately.
112          */
113         ino = 1;
114         while (ino <= ext2_fs->super->s_inodes_count) {
115                 ext2_ino_t foo;
116                 ext2fs_new_inode(ext2_fs, ino, 0, NULL, &foo);
117                 ino += EXT2_INODES_PER_GROUP(ext2_fs->super);
118         }
119
120         *ret_fs = ext2_fs;
121         return 0;
122 fail:
123         return -1;
124 }
125
126 static int close_ext2fs(ext2_filsys fs)
127 {
128         ext2fs_close(fs);
129         return 0;
130 }
131
132 static int ext2_alloc_block(ext2_filsys fs, u64 goal, u64 *block_ret)
133 {
134         blk_t block;
135
136         if (!ext2fs_new_block(fs, goal, NULL, &block)) {
137                 ext2fs_fast_mark_block_bitmap(fs->block_map, block);
138                 *block_ret = block;
139                 return 0;
140         }
141         return -ENOSPC;
142 }
143
144 static int ext2_alloc_block_range(ext2_filsys fs, u64 goal, int num,
145                 u64 *block_ret)
146 {
147         blk_t block;
148         ext2fs_block_bitmap bitmap = fs->block_map;
149         blk_t start = ext2fs_get_block_bitmap_start(bitmap);
150         blk_t end = ext2fs_get_block_bitmap_end(bitmap);
151
152         for (block = max_t(u64, goal, start); block + num < end; block++) {
153                 if (ext2fs_fast_test_block_bitmap_range(bitmap, block, num)) {
154                         ext2fs_fast_mark_block_bitmap_range(bitmap, block,
155                                         num);
156                         *block_ret = block;
157                         return 0;
158                 }
159         }
160         return -ENOSPC;
161 }
162
163 static int ext2_free_block(ext2_filsys fs, u64 block)
164 {
165         BUG_ON(block != (blk_t)block);
166         ext2fs_fast_unmark_block_bitmap(fs->block_map, block);
167         return 0;
168 }
169
170 static int ext2_free_block_range(ext2_filsys fs, u64 block, int num)
171 {
172         BUG_ON(block != (blk_t)block);
173         ext2fs_fast_unmark_block_bitmap_range(fs->block_map, block, num);
174         return 0;
175 }
176
177 static int cache_free_extents(struct btrfs_root *root, ext2_filsys ext2_fs)
178
179 {
180         int i, ret = 0;
181         blk_t block;
182         u64 bytenr;
183         u64 blocksize = ext2_fs->blocksize;
184
185         block = ext2_fs->super->s_first_data_block;
186         for (; block < ext2_fs->super->s_blocks_count; block++) {
187                 if (ext2fs_fast_test_block_bitmap(ext2_fs->block_map, block))
188                         continue;
189                 bytenr = block * blocksize;
190                 ret = set_extent_dirty(&root->fs_info->free_space_cache,
191                                        bytenr, bytenr + blocksize - 1, 0);
192                 BUG_ON(ret);
193         }
194
195         for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
196                 bytenr = btrfs_sb_offset(i);
197                 bytenr &= ~((u64)BTRFS_STRIPE_LEN - 1);
198                 if (bytenr >= blocksize * ext2_fs->super->s_blocks_count)
199                         break;
200                 clear_extent_dirty(&root->fs_info->free_space_cache, bytenr,
201                                    bytenr + BTRFS_STRIPE_LEN - 1, 0);
202         }
203
204         clear_extent_dirty(&root->fs_info->free_space_cache,
205                            0, BTRFS_SUPER_INFO_OFFSET - 1, 0);
206
207         return 0;
208 }
209
210 static int custom_alloc_extent(struct btrfs_root *root, u64 num_bytes,
211                                u64 hint_byte, struct btrfs_key *ins)
212 {
213         u64 start;
214         u64 end;
215         u64 last = hint_byte;
216         int ret;
217         int wrapped = 0;
218         struct btrfs_block_group_cache *cache;
219
220         while(1) {
221                 ret = find_first_extent_bit(&root->fs_info->free_space_cache,
222                                             last, &start, &end, EXTENT_DIRTY);
223                 if (ret) {
224                         if (wrapped++ == 0) {
225                                 last = 0;
226                                 continue;
227                         } else {
228                                 goto fail;
229                         }
230                 }
231
232                 start = max(last, start);
233                 last = end + 1;
234                 if (last - start < num_bytes)
235                         continue;
236
237                 last = start + num_bytes;
238                 if (test_range_bit(&root->fs_info->pinned_extents,
239                                    start, last - 1, EXTENT_DIRTY, 0))
240                         continue;
241
242                 cache = btrfs_lookup_block_group(root->fs_info, start);
243                 BUG_ON(!cache);
244                 if (cache->flags & BTRFS_BLOCK_GROUP_SYSTEM ||
245                     last > cache->key.objectid + cache->key.offset) {
246                         last = cache->key.objectid + cache->key.offset;
247                         continue;
248                 }
249
250                 clear_extent_dirty(&root->fs_info->free_space_cache,
251                                    start, start + num_bytes - 1, 0);
252
253                 ins->objectid = start;
254                 ins->offset = num_bytes;
255                 ins->type = BTRFS_EXTENT_ITEM_KEY;
256                 return 0;
257         }
258 fail:
259         fprintf(stderr, "not enough free space\n");
260         return -ENOSPC;
261 }
262
263 static int intersect_with_sb(u64 bytenr, u64 num_bytes)
264 {
265         int i;
266         u64 offset;
267
268         for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
269                 offset = btrfs_sb_offset(i);
270                 offset &= ~((u64)BTRFS_STRIPE_LEN - 1);
271
272                 if (bytenr < offset + BTRFS_STRIPE_LEN &&
273                     bytenr + num_bytes > offset)
274                         return 1;
275         }
276         return 0;
277 }
278
279 static int custom_free_extent(struct btrfs_root *root, u64 bytenr,
280                               u64 num_bytes)
281 {
282         return intersect_with_sb(bytenr, num_bytes);
283 }
284
285 static struct btrfs_extent_ops extent_ops = {
286         .alloc_extent = custom_alloc_extent,
287         .free_extent = custom_free_extent,
288 };
289
290 struct dir_iterate_data {
291         struct btrfs_trans_handle *trans;
292         struct btrfs_root *root;
293         struct btrfs_inode_item *inode;
294         u64 objectid;
295         u64 index_cnt;
296         u64 parent;
297         int errcode;
298 };
299
300 static u8 filetype_conversion_table[EXT2_FT_MAX] = {
301         [EXT2_FT_UNKNOWN]       = BTRFS_FT_UNKNOWN,
302         [EXT2_FT_REG_FILE]      = BTRFS_FT_REG_FILE,
303         [EXT2_FT_DIR]           = BTRFS_FT_DIR,
304         [EXT2_FT_CHRDEV]        = BTRFS_FT_CHRDEV,
305         [EXT2_FT_BLKDEV]        = BTRFS_FT_BLKDEV,
306         [EXT2_FT_FIFO]          = BTRFS_FT_FIFO,
307         [EXT2_FT_SOCK]          = BTRFS_FT_SOCK,
308         [EXT2_FT_SYMLINK]       = BTRFS_FT_SYMLINK,
309 };
310
311 static int dir_iterate_proc(ext2_ino_t dir, int entry,
312                             struct ext2_dir_entry *dirent,
313                             int offset, int blocksize,
314                             char *buf,void *priv_data)
315 {
316         int ret;
317         int file_type;
318         u64 objectid;
319         u64 inode_size;
320         char dotdot[] = "..";
321         struct btrfs_key location;
322         struct dir_iterate_data *idata = (struct dir_iterate_data *)priv_data;
323         int name_len;
324
325         name_len = dirent->name_len & 0xFF;
326
327         objectid = dirent->inode + INO_OFFSET;
328         if (!strncmp(dirent->name, dotdot, name_len)) {
329                 if (name_len == 2) {
330                         BUG_ON(idata->parent != 0);
331                         idata->parent = objectid;
332                 }
333                 return 0;
334         }
335         if (dirent->inode < EXT2_GOOD_OLD_FIRST_INO)
336                 return 0;
337
338         location.objectid = objectid;
339         location.offset = 0;
340         btrfs_set_key_type(&location, BTRFS_INODE_ITEM_KEY);
341
342         file_type = dirent->name_len >> 8;
343         BUG_ON(file_type > EXT2_FT_SYMLINK);
344         ret = btrfs_insert_dir_item(idata->trans, idata->root,
345                                     dirent->name, name_len,
346                                     idata->objectid, &location,
347                                     filetype_conversion_table[file_type],
348                                     idata->index_cnt);
349         if (ret)
350                 goto fail;
351         ret = btrfs_insert_inode_ref(idata->trans, idata->root,
352                                      dirent->name, name_len,
353                                      objectid, idata->objectid,
354                                      idata->index_cnt);
355         if (ret)
356                 goto fail;
357         idata->index_cnt++;
358         inode_size = btrfs_stack_inode_size(idata->inode) +
359                      name_len * 2;
360         btrfs_set_stack_inode_size(idata->inode, inode_size);
361         return 0;
362 fail:
363         idata->errcode = ret;
364         return BLOCK_ABORT;
365 }
366
367 static int create_dir_entries(struct btrfs_trans_handle *trans,
368                               struct btrfs_root *root, u64 objectid,
369                               struct btrfs_inode_item *btrfs_inode,
370                               ext2_filsys ext2_fs, ext2_ino_t ext2_ino)
371 {
372         int ret;
373         errcode_t err;
374         struct dir_iterate_data data = {
375                 .trans          = trans,
376                 .root           = root,
377                 .inode          = btrfs_inode,
378                 .objectid       = objectid,
379                 .index_cnt      = 2,
380                 .parent         = 0,
381                 .errcode        = 0,
382         };
383
384         err = ext2fs_dir_iterate2(ext2_fs, ext2_ino, 0, NULL,
385                                   dir_iterate_proc, &data);
386         if (err)
387                 goto error;
388         ret = data.errcode;
389         if (ret == 0 && data.parent == objectid) {
390                 ret = btrfs_insert_inode_ref(trans, root, "..", 2,
391                                              objectid, objectid, 0);
392         }
393         return ret;
394 error:
395         fprintf(stderr, "ext2fs_dir_iterate2: %s\n", error_message(err));
396         return -1;
397 }
398
399 static int read_disk_extent(struct btrfs_root *root, u64 bytenr,
400                             u32 num_bytes, char *buffer)
401 {
402         int ret;
403         struct btrfs_fs_devices *fs_devs = root->fs_info->fs_devices;
404
405         ret = pread(fs_devs->latest_bdev, buffer, num_bytes, bytenr);
406         if (ret != num_bytes)
407                 goto fail;
408         ret = 0;
409 fail:
410         if (ret > 0)
411                 ret = -1;
412         return ret;
413 }
414
415 static int csum_disk_extent(struct btrfs_trans_handle *trans,
416                             struct btrfs_root *root,
417                             u64 disk_bytenr, u64 num_bytes)
418 {
419         u32 blocksize = root->sectorsize;
420         u64 offset;
421         char *buffer;
422         int ret = 0;
423
424         buffer = malloc(blocksize);
425         if (!buffer)
426                 return -ENOMEM;
427         for (offset = 0; offset < num_bytes; offset += blocksize) {
428                 ret = read_disk_extent(root, disk_bytenr + offset,
429                                         blocksize, buffer);
430                 if (ret)
431                         break;
432                 ret = btrfs_csum_file_block(trans,
433                                             root->fs_info->csum_root,
434                                             disk_bytenr + num_bytes,
435                                             disk_bytenr + offset,
436                                             buffer, blocksize);
437                 if (ret)
438                         break;
439         }
440         free(buffer);
441         return ret;
442 }
443
444 static int record_file_blocks(struct btrfs_trans_handle *trans,
445                               struct btrfs_root *root, u64 objectid,
446                               struct btrfs_inode_item *inode,
447                               u64 file_block, u64 disk_block,
448                               u64 num_blocks, int checksum)
449 {
450         int ret;
451         u64 file_pos = file_block * root->sectorsize;
452         u64 disk_bytenr = disk_block * root->sectorsize;
453         u64 num_bytes = num_blocks * root->sectorsize;
454         ret = btrfs_record_file_extent(trans, root, objectid, inode, file_pos,
455                                         disk_bytenr, num_bytes);
456
457         if (ret || !checksum || disk_bytenr == 0)
458                 return ret;
459
460         return csum_disk_extent(trans, root, disk_bytenr, num_bytes);
461 }
462
463 struct blk_iterate_data {
464         struct btrfs_trans_handle *trans;
465         struct btrfs_root *root;
466         struct btrfs_inode_item *inode;
467         u64 objectid;
468         u64 first_block;
469         u64 disk_block;
470         u64 num_blocks;
471         u64 boundary;
472         int checksum;
473         int errcode;
474 };
475
476 static int block_iterate_proc(ext2_filsys ext2_fs,
477                               u64 disk_block, u64 file_block,
478                               struct blk_iterate_data *idata)
479 {
480         int ret;
481         int sb_region;
482         int do_barrier;
483         struct btrfs_root *root = idata->root;
484         struct btrfs_trans_handle *trans = idata->trans;
485         struct btrfs_block_group_cache *cache;
486         u64 bytenr = disk_block * root->sectorsize;
487
488         sb_region = intersect_with_sb(bytenr, root->sectorsize);
489         do_barrier = sb_region || disk_block >= idata->boundary;
490         if ((idata->num_blocks > 0 && do_barrier) ||
491             (file_block > idata->first_block + idata->num_blocks) ||
492             (disk_block != idata->disk_block + idata->num_blocks)) {
493                 if (idata->num_blocks > 0) {
494                         ret = record_file_blocks(trans, root, idata->objectid,
495                                         idata->inode, idata->first_block,
496                                         idata->disk_block, idata->num_blocks,
497                                         idata->checksum);
498                         if (ret)
499                                 goto fail;
500                         idata->first_block += idata->num_blocks;
501                         idata->num_blocks = 0;
502                 }
503                 if (file_block > idata->first_block) {
504                         ret = record_file_blocks(trans, root, idata->objectid,
505                                         idata->inode, idata->first_block,
506                                         0, file_block - idata->first_block,
507                                         idata->checksum);
508                         if (ret)
509                                 goto fail;
510                 }
511
512                 if (sb_region) {
513                         bytenr += BTRFS_STRIPE_LEN - 1;
514                         bytenr &= ~((u64)BTRFS_STRIPE_LEN - 1);
515                 } else {
516                         cache = btrfs_lookup_block_group(root->fs_info, bytenr);
517                         BUG_ON(!cache);
518                         bytenr = cache->key.objectid + cache->key.offset;
519                 }
520
521                 idata->first_block = file_block;
522                 idata->disk_block = disk_block;
523                 idata->boundary = bytenr / root->sectorsize;
524         }
525         idata->num_blocks++;
526         return 0;
527 fail:
528         idata->errcode = ret;
529         return BLOCK_ABORT;
530 }
531
532 static int __block_iterate_proc(ext2_filsys fs, blk_t *blocknr,
533                                 e2_blkcnt_t blockcnt, blk_t ref_block,
534                                 int ref_offset, void *priv_data)
535 {
536         struct blk_iterate_data *idata;
537         idata = (struct blk_iterate_data *)priv_data;
538         return block_iterate_proc(fs, *blocknr, blockcnt, idata);
539 }
540
541 /*
542  * traverse file's data blocks, record these data blocks as file extents.
543  */
544 static int create_file_extents(struct btrfs_trans_handle *trans,
545                                struct btrfs_root *root, u64 objectid,
546                                struct btrfs_inode_item *btrfs_inode,
547                                ext2_filsys ext2_fs, ext2_ino_t ext2_ino,
548                                int datacsum, int packing)
549 {
550         int ret;
551         char *buffer = NULL;
552         errcode_t err;
553         u32 last_block;
554         u32 sectorsize = root->sectorsize;
555         u64 inode_size = btrfs_stack_inode_size(btrfs_inode);
556         struct blk_iterate_data data = {
557                 .trans          = trans,
558                 .root           = root,
559                 .inode          = btrfs_inode,
560                 .objectid       = objectid,
561                 .first_block    = 0,
562                 .disk_block     = 0,
563                 .num_blocks     = 0,
564                 .boundary       = (u64)-1,
565                 .checksum       = datacsum,
566                 .errcode        = 0,
567         };
568         err = ext2fs_block_iterate2(ext2_fs, ext2_ino, BLOCK_FLAG_DATA_ONLY,
569                                     NULL, __block_iterate_proc, &data);
570         if (err)
571                 goto error;
572         ret = data.errcode;
573         if (ret)
574                 goto fail;
575         if (packing && data.first_block == 0 && data.num_blocks > 0 &&
576             inode_size <= BTRFS_MAX_INLINE_DATA_SIZE(root)) {
577                 u64 num_bytes = data.num_blocks * sectorsize;
578                 u64 disk_bytenr = data.disk_block * sectorsize;
579                 u64 nbytes;
580
581                 buffer = malloc(num_bytes);
582                 if (!buffer)
583                         return -ENOMEM;
584                 ret = read_disk_extent(root, disk_bytenr, num_bytes, buffer);
585                 if (ret)
586                         goto fail;
587                 if (num_bytes > inode_size)
588                         num_bytes = inode_size;
589                 ret = btrfs_insert_inline_extent(trans, root, objectid,
590                                                  0, buffer, num_bytes);
591                 if (ret)
592                         goto fail;
593                 nbytes = btrfs_stack_inode_nbytes(btrfs_inode) + num_bytes;
594                 btrfs_set_stack_inode_nbytes(btrfs_inode, nbytes);
595         } else if (data.num_blocks > 0) {
596                 ret = record_file_blocks(trans, root, objectid, btrfs_inode,
597                                          data.first_block, data.disk_block,
598                                          data.num_blocks, data.checksum);
599                 if (ret)
600                         goto fail;
601         }
602         data.first_block += data.num_blocks;
603         last_block = (inode_size + sectorsize - 1) / sectorsize;
604         if (last_block > data.first_block) {
605                 ret = record_file_blocks(trans, root, objectid, btrfs_inode,
606                                          data.first_block, 0, last_block -
607                                          data.first_block, data.checksum);
608         }
609 fail:
610         free(buffer);
611         return ret;
612 error:
613         fprintf(stderr, "ext2fs_block_iterate2: %s\n", error_message(err));
614         return -1;
615 }
616
617 static int create_symbol_link(struct btrfs_trans_handle *trans,
618                               struct btrfs_root *root, u64 objectid,
619                               struct btrfs_inode_item *btrfs_inode,
620                               ext2_filsys ext2_fs, ext2_ino_t ext2_ino,
621                               struct ext2_inode *ext2_inode)
622 {
623         int ret;
624         char *pathname;
625         u64 inode_size = btrfs_stack_inode_size(btrfs_inode);
626         if (ext2fs_inode_data_blocks(ext2_fs, ext2_inode)) {
627                 btrfs_set_stack_inode_size(btrfs_inode, inode_size + 1);
628                 ret = create_file_extents(trans, root, objectid, btrfs_inode,
629                                           ext2_fs, ext2_ino, 1, 1);
630                 btrfs_set_stack_inode_size(btrfs_inode, inode_size);
631                 return ret;
632         }
633
634         pathname = (char *)&(ext2_inode->i_block[0]);
635         BUG_ON(pathname[inode_size] != 0);
636         ret = btrfs_insert_inline_extent(trans, root, objectid, 0,
637                                          pathname, inode_size + 1);
638         btrfs_set_stack_inode_nbytes(btrfs_inode, inode_size + 1);
639         return ret;
640 }
641
642 /*
643  * Following xattr/acl related codes are based on codes in
644  * fs/ext3/xattr.c and fs/ext3/acl.c
645  */
646 #define EXT2_XATTR_BHDR(ptr) ((struct ext2_ext_attr_header *)(ptr))
647 #define EXT2_XATTR_BFIRST(ptr) \
648         ((struct ext2_ext_attr_entry *)(EXT2_XATTR_BHDR(ptr) + 1))
649 #define EXT2_XATTR_IHDR(inode) \
650         ((struct ext2_ext_attr_header *) ((void *)(inode) + \
651                 EXT2_GOOD_OLD_INODE_SIZE + (inode)->i_extra_isize))
652 #define EXT2_XATTR_IFIRST(inode) \
653         ((struct ext2_ext_attr_entry *) ((void *)EXT2_XATTR_IHDR(inode) + \
654                 sizeof(EXT2_XATTR_IHDR(inode)->h_magic)))
655
656 static int ext2_xattr_check_names(struct ext2_ext_attr_entry *entry,
657                                   const void *end)
658 {
659         struct ext2_ext_attr_entry *next;
660
661         while (!EXT2_EXT_IS_LAST_ENTRY(entry)) {
662                 next = EXT2_EXT_ATTR_NEXT(entry);
663                 if ((void *)next >= end)
664                         return -EIO;
665                 entry = next;
666         }
667         return 0;
668 }
669
670 static int ext2_xattr_check_block(const char *buf, size_t size)
671 {
672         int error;
673         struct ext2_ext_attr_header *header = EXT2_XATTR_BHDR(buf);
674
675         if (header->h_magic != EXT2_EXT_ATTR_MAGIC ||
676             header->h_blocks != 1)
677                 return -EIO;
678         error = ext2_xattr_check_names(EXT2_XATTR_BFIRST(buf), buf + size);
679         return error;
680 }
681
682 static int ext2_xattr_check_entry(struct ext2_ext_attr_entry *entry,
683                                   size_t size)
684 {
685         size_t value_size = entry->e_value_size;
686
687         if (entry->e_value_block != 0 || value_size > size ||
688             entry->e_value_offs + value_size > size)
689                 return -EIO;
690         return 0;
691 }
692
693 #define EXT2_ACL_VERSION        0x0001
694
695 typedef struct {
696         __le16          e_tag;
697         __le16          e_perm;
698         __le32          e_id;
699 } ext2_acl_entry;
700
701 typedef struct {
702         __le16          e_tag;
703         __le16          e_perm;
704 } ext2_acl_entry_short;
705
706 typedef struct {
707         __le32          a_version;
708 } ext2_acl_header;
709
710 static inline int ext2_acl_count(size_t size)
711 {
712         ssize_t s;
713         size -= sizeof(ext2_acl_header);
714         s = size - 4 * sizeof(ext2_acl_entry_short);
715         if (s < 0) {
716                 if (size % sizeof(ext2_acl_entry_short))
717                         return -1;
718                 return size / sizeof(ext2_acl_entry_short);
719         } else {
720                 if (s % sizeof(ext2_acl_entry))
721                         return -1;
722                 return s / sizeof(ext2_acl_entry) + 4;
723         }
724 }
725
726 #define ACL_EA_VERSION          0x0002
727
728 typedef struct {
729         __le16          e_tag;
730         __le16          e_perm;
731         __le32          e_id;
732 } acl_ea_entry;
733
734 typedef struct {
735         __le32          a_version;
736         acl_ea_entry    a_entries[0];
737 } acl_ea_header;
738
739 static inline size_t acl_ea_size(int count)
740 {
741         return sizeof(acl_ea_header) + count * sizeof(acl_ea_entry);
742 }
743
744 static int ext2_acl_to_xattr(void *dst, const void *src,
745                              size_t dst_size, size_t src_size)
746 {
747         int i, count;
748         const void *end = src + src_size;
749         acl_ea_header *ext_acl = (acl_ea_header *)dst;
750         acl_ea_entry *dst_entry = ext_acl->a_entries;
751         ext2_acl_entry *src_entry;
752
753         if (src_size < sizeof(ext2_acl_header))
754                 goto fail;
755         if (((ext2_acl_header *)src)->a_version !=
756             cpu_to_le32(EXT2_ACL_VERSION))
757                 goto fail;
758         src += sizeof(ext2_acl_header);
759         count = ext2_acl_count(src_size);
760         if (count <= 0)
761                 goto fail;
762
763         BUG_ON(dst_size < acl_ea_size(count));
764         ext_acl->a_version = cpu_to_le32(ACL_EA_VERSION);
765         for (i = 0; i < count; i++, dst_entry++) {
766                 src_entry = (ext2_acl_entry *)src;
767                 if (src + sizeof(ext2_acl_entry_short) > end)
768                         goto fail;
769                 dst_entry->e_tag = src_entry->e_tag;
770                 dst_entry->e_perm = src_entry->e_perm;
771                 switch (le16_to_cpu(src_entry->e_tag)) {
772                 case ACL_USER_OBJ:
773                 case ACL_GROUP_OBJ:
774                 case ACL_MASK:
775                 case ACL_OTHER:
776                         src += sizeof(ext2_acl_entry_short);
777                         dst_entry->e_id = cpu_to_le32(ACL_UNDEFINED_ID);
778                         break;
779                 case ACL_USER:
780                 case ACL_GROUP:
781                         src += sizeof(ext2_acl_entry);
782                         if (src > end)
783                                 goto fail;
784                         dst_entry->e_id = src_entry->e_id;
785                         break;
786                 default:
787                         goto fail;
788                 }
789         }
790         if (src != end)
791                 goto fail;
792         return 0;
793 fail:
794         return -EINVAL;
795 }
796
797 static char *xattr_prefix_table[] = {
798         [1] =   "user.",
799         [2] =   "system.posix_acl_access",
800         [3] =   "system.posix_acl_default",
801         [4] =   "trusted.",
802         [6] =   "security.",
803 };
804
805 static int copy_single_xattr(struct btrfs_trans_handle *trans,
806                              struct btrfs_root *root, u64 objectid,
807                              struct ext2_ext_attr_entry *entry,
808                              const void *data, u32 datalen)
809 {
810         int ret = 0;
811         int name_len;
812         int name_index;
813         void *databuf = NULL;
814         char namebuf[XATTR_NAME_MAX + 1];
815
816         name_index = entry->e_name_index;
817         if (name_index >= ARRAY_SIZE(xattr_prefix_table) ||
818             xattr_prefix_table[name_index] == NULL)
819                 return -EOPNOTSUPP;
820         name_len = strlen(xattr_prefix_table[name_index]) +
821                    entry->e_name_len;
822         if (name_len >= sizeof(namebuf))
823                 return -ERANGE;
824
825         if (name_index == 2 || name_index == 3) {
826                 size_t bufsize = acl_ea_size(ext2_acl_count(datalen));
827                 databuf = malloc(bufsize);
828                 if (!databuf)
829                        return -ENOMEM;
830                 ret = ext2_acl_to_xattr(databuf, data, bufsize, datalen);
831                 if (ret)
832                         goto out;
833                 data = databuf;
834                 datalen = bufsize;
835         }
836         strncpy(namebuf, xattr_prefix_table[name_index], XATTR_NAME_MAX);
837         strncat(namebuf, EXT2_EXT_ATTR_NAME(entry), entry->e_name_len);
838         if (name_len + datalen > BTRFS_LEAF_DATA_SIZE(root) -
839             sizeof(struct btrfs_item) - sizeof(struct btrfs_dir_item)) {
840                 fprintf(stderr, "skip large xattr on inode %Lu name %.*s\n",
841                         objectid - INO_OFFSET, name_len, namebuf);
842                 goto out;
843         }
844         ret = btrfs_insert_xattr_item(trans, root, namebuf, name_len,
845                                       data, datalen, objectid);
846 out:
847         free(databuf);
848         return ret;
849 }
850
851 static int copy_extended_attrs(struct btrfs_trans_handle *trans,
852                                struct btrfs_root *root, u64 objectid,
853                                struct btrfs_inode_item *btrfs_inode,
854                                ext2_filsys ext2_fs, ext2_ino_t ext2_ino)
855 {
856         int ret = 0;
857         int inline_ea = 0;
858         errcode_t err;
859         u32 datalen;
860         u32 block_size = ext2_fs->blocksize;
861         u32 inode_size = EXT2_INODE_SIZE(ext2_fs->super);
862         struct ext2_inode_large *ext2_inode;
863         struct ext2_ext_attr_entry *entry;
864         void *data;
865         char *buffer = NULL;
866         char inode_buf[EXT2_GOOD_OLD_INODE_SIZE];
867
868         if (inode_size <= EXT2_GOOD_OLD_INODE_SIZE) {
869                 ext2_inode = (struct ext2_inode_large *)inode_buf;
870         } else {
871                 ext2_inode = (struct ext2_inode_large *)malloc(inode_size);
872                 if (!ext2_inode)
873                        return -ENOMEM;
874         }
875         err = ext2fs_read_inode_full(ext2_fs, ext2_ino, (void *)ext2_inode,
876                                      inode_size);
877         if (err) {
878                 fprintf(stderr, "ext2fs_read_inode_full: %s\n",
879                         error_message(err));
880                 ret = -1;
881                 goto out;
882         }
883
884         if (ext2_ino > ext2_fs->super->s_first_ino &&
885             inode_size > EXT2_GOOD_OLD_INODE_SIZE) {
886                 if (EXT2_GOOD_OLD_INODE_SIZE +
887                     ext2_inode->i_extra_isize > inode_size) {
888                         ret = -EIO;
889                         goto out;
890                 }
891                 if (ext2_inode->i_extra_isize != 0 &&
892                     EXT2_XATTR_IHDR(ext2_inode)->h_magic ==
893                     EXT2_EXT_ATTR_MAGIC) {
894                         inline_ea = 1;
895                 }
896         }
897         if (inline_ea) {
898                 int total;
899                 void *end = (void *)ext2_inode + inode_size;
900                 entry = EXT2_XATTR_IFIRST(ext2_inode);
901                 total = end - (void *)entry;
902                 ret = ext2_xattr_check_names(entry, end);
903                 if (ret)
904                         goto out;
905                 while (!EXT2_EXT_IS_LAST_ENTRY(entry)) {
906                         ret = ext2_xattr_check_entry(entry, total);
907                         if (ret)
908                                 goto out;
909                         data = (void *)EXT2_XATTR_IFIRST(ext2_inode) +
910                                 entry->e_value_offs;
911                         datalen = entry->e_value_size;
912                         ret = copy_single_xattr(trans, root, objectid,
913                                                 entry, data, datalen);
914                         if (ret)
915                                 goto out;
916                         entry = EXT2_EXT_ATTR_NEXT(entry);
917                 }
918         }
919
920         if (ext2_inode->i_file_acl == 0)
921                 goto out;
922
923         buffer = malloc(block_size);
924         if (!buffer) {
925                 ret = -ENOMEM;
926                 goto out;
927         }
928         err = ext2fs_read_ext_attr(ext2_fs, ext2_inode->i_file_acl, buffer);
929         if (err) {
930                 fprintf(stderr, "ext2fs_read_ext_attr: %s\n",
931                         error_message(err));
932                 ret = -1;
933                 goto out;
934         }
935         ret = ext2_xattr_check_block(buffer, block_size);
936         if (ret)
937                 goto out;
938
939         entry = EXT2_XATTR_BFIRST(buffer);
940         while (!EXT2_EXT_IS_LAST_ENTRY(entry)) {
941                 ret = ext2_xattr_check_entry(entry, block_size);
942                 if (ret)
943                         goto out;
944                 data = buffer + entry->e_value_offs;
945                 datalen = entry->e_value_size;
946                 ret = copy_single_xattr(trans, root, objectid,
947                                         entry, data, datalen);
948                 if (ret)
949                         goto out;
950                 entry = EXT2_EXT_ATTR_NEXT(entry);
951         }
952 out:
953         free(buffer);
954         if ((void *)ext2_inode != inode_buf)
955                 free(ext2_inode);
956         return ret;
957 }
958 #define MINORBITS       20
959 #define MKDEV(ma, mi)   (((ma) << MINORBITS) | (mi))
960
961 static inline dev_t old_decode_dev(u16 val)
962 {
963         return MKDEV((val >> 8) & 255, val & 255);
964 }
965
966 static inline dev_t new_decode_dev(u32 dev)
967 {
968         unsigned major = (dev & 0xfff00) >> 8;
969         unsigned minor = (dev & 0xff) | ((dev >> 12) & 0xfff00);
970         return MKDEV(major, minor);
971 }
972
973 static int copy_inode_item(struct btrfs_inode_item *dst,
974                            struct ext2_inode *src, u32 blocksize)
975 {
976         btrfs_set_stack_inode_generation(dst, 1);
977         btrfs_set_stack_inode_size(dst, src->i_size);
978         btrfs_set_stack_inode_nbytes(dst, 0);
979         btrfs_set_stack_inode_block_group(dst, 0);
980         btrfs_set_stack_inode_nlink(dst, src->i_links_count);
981         btrfs_set_stack_inode_uid(dst, src->i_uid | (src->i_uid_high << 16));
982         btrfs_set_stack_inode_gid(dst, src->i_gid | (src->i_gid_high << 16));
983         btrfs_set_stack_inode_mode(dst, src->i_mode);
984         btrfs_set_stack_inode_rdev(dst, 0);
985         btrfs_set_stack_inode_flags(dst, 0);
986         btrfs_set_stack_timespec_sec(&dst->atime, src->i_atime);
987         btrfs_set_stack_timespec_nsec(&dst->atime, 0);
988         btrfs_set_stack_timespec_sec(&dst->ctime, src->i_ctime);
989         btrfs_set_stack_timespec_nsec(&dst->ctime, 0);
990         btrfs_set_stack_timespec_sec(&dst->mtime, src->i_mtime);
991         btrfs_set_stack_timespec_nsec(&dst->mtime, 0);
992         btrfs_set_stack_timespec_sec(&dst->otime, 0);
993         btrfs_set_stack_timespec_nsec(&dst->otime, 0);
994
995         if (S_ISDIR(src->i_mode)) {
996                 btrfs_set_stack_inode_size(dst, 0);
997                 btrfs_set_stack_inode_nlink(dst, 1);
998         }
999         if (S_ISREG(src->i_mode)) {
1000                 btrfs_set_stack_inode_size(dst, (u64)src->i_size_high << 32 |
1001                                            (u64)src->i_size);
1002         }
1003         if (!S_ISREG(src->i_mode) && !S_ISDIR(src->i_mode) &&
1004             !S_ISLNK(src->i_mode)) {
1005                 if (src->i_block[0]) {
1006                         btrfs_set_stack_inode_rdev(dst,
1007                                 old_decode_dev(src->i_block[0]));
1008                 } else {
1009                         btrfs_set_stack_inode_rdev(dst,
1010                                 new_decode_dev(src->i_block[1]));
1011                 }
1012         }
1013         return 0;
1014 }
1015
1016 /*
1017  * copy a single inode. do all the required works, such as cloning
1018  * inode item, creating file extents and creating directory entries.
1019  */
1020 static int copy_single_inode(struct btrfs_trans_handle *trans,
1021                              struct btrfs_root *root, u64 objectid,
1022                              ext2_filsys ext2_fs, ext2_ino_t ext2_ino,
1023                              struct ext2_inode *ext2_inode,
1024                              int datacsum, int packing, int noxattr)
1025 {
1026         int ret;
1027         struct btrfs_key inode_key;
1028         struct btrfs_inode_item btrfs_inode;
1029
1030         if (ext2_inode->i_links_count == 0)
1031                 return 0;
1032
1033         copy_inode_item(&btrfs_inode, ext2_inode, ext2_fs->blocksize);
1034         if (!datacsum && S_ISREG(ext2_inode->i_mode)) {
1035                 u32 flags = btrfs_stack_inode_flags(&btrfs_inode) |
1036                             BTRFS_INODE_NODATASUM;
1037                 btrfs_set_stack_inode_flags(&btrfs_inode, flags);
1038         }
1039
1040         switch (ext2_inode->i_mode & S_IFMT) {
1041         case S_IFREG:
1042                 ret = create_file_extents(trans, root, objectid, &btrfs_inode,
1043                                         ext2_fs, ext2_ino, datacsum, packing);
1044                 break;
1045         case S_IFDIR:
1046                 ret = create_dir_entries(trans, root, objectid, &btrfs_inode,
1047                                          ext2_fs, ext2_ino);
1048                 break;
1049         case S_IFLNK:
1050                 ret = create_symbol_link(trans, root, objectid, &btrfs_inode,
1051                                          ext2_fs, ext2_ino, ext2_inode);
1052                 break;
1053         default:
1054                 ret = 0;
1055                 break;
1056         }
1057         if (ret)
1058                 return ret;
1059
1060         if (!noxattr) {
1061                 ret = copy_extended_attrs(trans, root, objectid, &btrfs_inode,
1062                                           ext2_fs, ext2_ino);
1063                 if (ret)
1064                         return ret;
1065         }
1066         inode_key.objectid = objectid;
1067         inode_key.offset = 0;
1068         btrfs_set_key_type(&inode_key, BTRFS_INODE_ITEM_KEY);
1069         ret = btrfs_insert_inode(trans, root, objectid, &btrfs_inode);
1070         return ret;
1071 }
1072
1073 static int copy_disk_extent(struct btrfs_root *root, u64 dst_bytenr,
1074                             u64 src_bytenr, u32 num_bytes)
1075 {
1076         int ret;
1077         char *buffer;
1078         struct btrfs_fs_devices *fs_devs = root->fs_info->fs_devices;
1079
1080         buffer = malloc(num_bytes);
1081         if (!buffer)
1082                 return -ENOMEM;
1083         ret = pread(fs_devs->latest_bdev, buffer, num_bytes, src_bytenr);
1084         if (ret != num_bytes)
1085                 goto fail;
1086         ret = pwrite(fs_devs->latest_bdev, buffer, num_bytes, dst_bytenr);
1087         if (ret != num_bytes)
1088                 goto fail;
1089         ret = 0;
1090 fail:
1091         free(buffer);
1092         if (ret > 0)
1093                 ret = -1;
1094         return ret;
1095 }
1096 /*
1097  * scan ext2's inode bitmap and copy all used inodes.
1098  */
1099 static int copy_inodes(struct btrfs_root *root, ext2_filsys ext2_fs,
1100                        int datacsum, int packing, int noxattr, struct task_ctx *p)
1101 {
1102         int ret;
1103         errcode_t err;
1104         ext2_inode_scan ext2_scan;
1105         struct ext2_inode ext2_inode;
1106         ext2_ino_t ext2_ino;
1107         u64 objectid;
1108         struct btrfs_trans_handle *trans;
1109
1110         trans = btrfs_start_transaction(root, 1);
1111         if (!trans)
1112                 return -ENOMEM;
1113         err = ext2fs_open_inode_scan(ext2_fs, 0, &ext2_scan);
1114         if (err) {
1115                 fprintf(stderr, "ext2fs_open_inode_scan: %s\n", error_message(err));
1116                 return -1;
1117         }
1118         while (!(err = ext2fs_get_next_inode(ext2_scan, &ext2_ino,
1119                                              &ext2_inode))) {
1120                 /* no more inodes */
1121                 if (ext2_ino == 0)
1122                         break;
1123                 /* skip special inode in ext2fs */
1124                 if (ext2_ino < EXT2_GOOD_OLD_FIRST_INO &&
1125                     ext2_ino != EXT2_ROOT_INO)
1126                         continue;
1127                 objectid = ext2_ino + INO_OFFSET;
1128                 ret = copy_single_inode(trans, root,
1129                                         objectid, ext2_fs, ext2_ino,
1130                                         &ext2_inode, datacsum, packing,
1131                                         noxattr);
1132                 p->cur_copy_inodes++;
1133                 if (ret)
1134                         return ret;
1135                 if (trans->blocks_used >= 4096) {
1136                         ret = btrfs_commit_transaction(trans, root);
1137                         BUG_ON(ret);
1138                         trans = btrfs_start_transaction(root, 1);
1139                         BUG_ON(!trans);
1140                 }
1141         }
1142         if (err) {
1143                 fprintf(stderr, "ext2fs_get_next_inode: %s\n", error_message(err));
1144                 return -1;
1145         }
1146         ret = btrfs_commit_transaction(trans, root);
1147         BUG_ON(ret);
1148
1149         return ret;
1150 }
1151
1152 /*
1153  * Construct a range of ext2fs image file.
1154  * scan block allocation bitmap, find all blocks used by the ext2fs
1155  * in this range and create file extents that point to these blocks.
1156  *
1157  * Note: Before calling the function, no file extent points to blocks
1158  *       in this range
1159  */
1160 static int create_image_file_range(struct btrfs_trans_handle *trans,
1161                                    struct btrfs_root *root, u64 objectid,
1162                                    struct btrfs_inode_item *inode,
1163                                    u64 start_byte, u64 end_byte,
1164                                    ext2_filsys ext2_fs, int datacsum)
1165 {
1166         u32 blocksize = ext2_fs->blocksize;
1167         u32 block = start_byte / blocksize;
1168         u32 last_block = (end_byte + blocksize - 1) / blocksize;
1169         int ret = 0;
1170         struct blk_iterate_data data = {
1171                 .trans          = trans,
1172                 .root           = root,
1173                 .inode          = inode,
1174                 .objectid       = objectid,
1175                 .first_block    = block,
1176                 .disk_block     = 0,
1177                 .num_blocks     = 0,
1178                 .boundary       = (u64)-1,
1179                 .checksum       = datacsum,
1180                 .errcode        = 0,
1181         };
1182         for (; start_byte < end_byte; block++, start_byte += blocksize) {
1183                 if (!ext2fs_fast_test_block_bitmap(ext2_fs->block_map, block))
1184                         continue;
1185                 ret = block_iterate_proc(NULL, block, block, &data);
1186                 if (ret & BLOCK_ABORT) {
1187                         ret = data.errcode;
1188                         goto fail;
1189                 }
1190         }
1191         if (data.num_blocks > 0) {
1192                 ret = record_file_blocks(trans, root, objectid, inode,
1193                                          data.first_block, data.disk_block,
1194                                          data.num_blocks, datacsum);
1195                 if (ret)
1196                         goto fail;
1197                 data.first_block += data.num_blocks;
1198         }
1199         if (last_block > data.first_block) {
1200                 ret = record_file_blocks(trans, root, objectid, inode,
1201                                          data.first_block, 0, last_block -
1202                                          data.first_block, datacsum);
1203                 if (ret)
1204                         goto fail;
1205         }
1206 fail:
1207         return ret;
1208 }
1209 /*
1210  * Create the ext2fs image file.
1211  */
1212 static int create_ext2_image(struct btrfs_root *root, ext2_filsys ext2_fs,
1213                              const char *name, int datacsum)
1214 {
1215         int ret;
1216         struct btrfs_key key;
1217         struct btrfs_key location;
1218         struct btrfs_path path;
1219         struct btrfs_inode_item btrfs_inode;
1220         struct btrfs_inode_item *inode_item;
1221         struct extent_buffer *leaf;
1222         struct btrfs_fs_info *fs_info = root->fs_info;
1223         struct btrfs_root *extent_root = fs_info->extent_root;
1224         struct btrfs_trans_handle *trans;
1225         struct btrfs_extent_item *ei;
1226         struct btrfs_extent_inline_ref *iref;
1227         struct btrfs_extent_data_ref *dref;
1228         u64 bytenr;
1229         u64 num_bytes;
1230         u64 objectid;
1231         u64 last_byte;
1232         u64 first_free;
1233         u64 total_bytes;
1234         u64 flags = BTRFS_INODE_READONLY;
1235         u32 sectorsize = root->sectorsize;
1236
1237         total_bytes = btrfs_super_total_bytes(fs_info->super_copy);
1238         first_free =  BTRFS_SUPER_INFO_OFFSET + sectorsize * 2 - 1;
1239         first_free &= ~((u64)sectorsize - 1);
1240         if (!datacsum)
1241                 flags |= BTRFS_INODE_NODATASUM;
1242
1243         memset(&btrfs_inode, 0, sizeof(btrfs_inode));
1244         btrfs_set_stack_inode_generation(&btrfs_inode, 1);
1245         btrfs_set_stack_inode_size(&btrfs_inode, total_bytes);
1246         btrfs_set_stack_inode_nlink(&btrfs_inode, 1);
1247         btrfs_set_stack_inode_nbytes(&btrfs_inode, 0);
1248         btrfs_set_stack_inode_mode(&btrfs_inode, S_IFREG | 0400);
1249         btrfs_set_stack_inode_flags(&btrfs_inode,  flags);
1250         btrfs_init_path(&path);
1251         trans = btrfs_start_transaction(root, 1);
1252         BUG_ON(!trans);
1253
1254         objectid = btrfs_root_dirid(&root->root_item);
1255         ret = btrfs_find_free_objectid(trans, root, objectid, &objectid);
1256         if (ret)
1257                 goto fail;
1258
1259         /*
1260          * copy blocks covered by extent #0 to new positions. extent #0 is
1261          * special, we can't rely on relocate_extents_range to relocate it.
1262          */
1263         for (last_byte = 0; last_byte < first_free; last_byte += sectorsize) {
1264                 ret = custom_alloc_extent(root, sectorsize, 0, &key);
1265                 if (ret)
1266                         goto fail;
1267                 ret = copy_disk_extent(root, key.objectid, last_byte,
1268                                        sectorsize);
1269                 if (ret)
1270                         goto fail;
1271                 ret = btrfs_record_file_extent(trans, root, objectid,
1272                                                &btrfs_inode, last_byte,
1273                                                key.objectid, sectorsize);
1274                 if (ret)
1275                         goto fail;
1276                 if (datacsum) {
1277                         ret = csum_disk_extent(trans, root, key.objectid,
1278                                                sectorsize);
1279                         if (ret)
1280                                 goto fail;
1281                 }
1282         }
1283
1284         while(1) {
1285                 key.objectid = last_byte;
1286                 key.offset = 0;
1287                 btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
1288                 ret = btrfs_search_slot(trans, fs_info->extent_root,
1289                                         &key, &path, 0, 0);
1290                 if (ret < 0)
1291                         goto fail;
1292 next:
1293                 leaf = path.nodes[0];
1294                 if (path.slots[0] >= btrfs_header_nritems(leaf)) {
1295                         ret = btrfs_next_leaf(extent_root, &path);
1296                         if (ret < 0)
1297                                 goto fail;
1298                         if (ret > 0)
1299                                 break;
1300                         leaf = path.nodes[0];
1301                 }
1302                 btrfs_item_key_to_cpu(leaf, &key, path.slots[0]);
1303                 if (last_byte > key.objectid ||
1304                     key.type != BTRFS_EXTENT_ITEM_KEY) {
1305                         path.slots[0]++;
1306                         goto next;
1307                 }
1308
1309                 bytenr = key.objectid;
1310                 num_bytes = key.offset;
1311                 ei = btrfs_item_ptr(leaf, path.slots[0],
1312                                     struct btrfs_extent_item);
1313                 if (!(btrfs_extent_flags(leaf, ei) & BTRFS_EXTENT_FLAG_DATA)) {
1314                         path.slots[0]++;
1315                         goto next;
1316                 }
1317
1318                 BUG_ON(btrfs_item_size_nr(leaf, path.slots[0]) != sizeof(*ei) +
1319                        btrfs_extent_inline_ref_size(BTRFS_EXTENT_DATA_REF_KEY));
1320
1321                 iref = (struct btrfs_extent_inline_ref *)(ei + 1);
1322                 key.type = btrfs_extent_inline_ref_type(leaf, iref);
1323                 BUG_ON(key.type != BTRFS_EXTENT_DATA_REF_KEY);
1324                 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1325                 if (btrfs_extent_data_ref_root(leaf, dref) !=
1326                     BTRFS_FS_TREE_OBJECTID) {
1327                         path.slots[0]++;
1328                         goto next;
1329                 }
1330
1331                 if (bytenr > last_byte) {
1332                         ret = create_image_file_range(trans, root, objectid,
1333                                                       &btrfs_inode, last_byte,
1334                                                       bytenr, ext2_fs,
1335                                                       datacsum);
1336                         if (ret)
1337                                 goto fail;
1338                 }
1339                 ret = btrfs_record_file_extent(trans, root, objectid,
1340                                                &btrfs_inode, bytenr, bytenr,
1341                                                num_bytes);
1342                 if (ret)
1343                         goto fail;
1344                 last_byte = bytenr + num_bytes;
1345                 btrfs_release_path(&path);
1346
1347                 if (trans->blocks_used >= 4096) {
1348                         ret = btrfs_commit_transaction(trans, root);
1349                         BUG_ON(ret);
1350                         trans = btrfs_start_transaction(root, 1);
1351                         BUG_ON(!trans);
1352                 }
1353         }
1354         btrfs_release_path(&path);
1355         if (total_bytes > last_byte) {
1356                 ret = create_image_file_range(trans, root, objectid,
1357                                               &btrfs_inode, last_byte,
1358                                               total_bytes, ext2_fs,
1359                                               datacsum);
1360                 if (ret)
1361                         goto fail;
1362         }
1363
1364         ret = btrfs_insert_inode(trans, root, objectid, &btrfs_inode);
1365         if (ret)
1366                 goto fail;
1367
1368         location.objectid = objectid;
1369         location.offset = 0;
1370         btrfs_set_key_type(&location, BTRFS_INODE_ITEM_KEY);
1371         ret = btrfs_insert_dir_item(trans, root, name, strlen(name),
1372                                     btrfs_root_dirid(&root->root_item),
1373                                     &location, EXT2_FT_REG_FILE, objectid);
1374         if (ret)
1375                 goto fail;
1376         ret = btrfs_insert_inode_ref(trans, root, name, strlen(name),
1377                                      objectid,
1378                                      btrfs_root_dirid(&root->root_item),
1379                                      objectid);
1380         if (ret)
1381                 goto fail;
1382         location.objectid = btrfs_root_dirid(&root->root_item);
1383         location.offset = 0;
1384         btrfs_set_key_type(&location, BTRFS_INODE_ITEM_KEY);
1385         ret = btrfs_lookup_inode(trans, root, &path, &location, 1);
1386         if (ret)
1387                 goto fail;
1388         leaf = path.nodes[0];
1389         inode_item = btrfs_item_ptr(leaf, path.slots[0],
1390                                     struct btrfs_inode_item);
1391         btrfs_set_inode_size(leaf, inode_item, strlen(name) * 2 +
1392                              btrfs_inode_size(leaf, inode_item));
1393         btrfs_mark_buffer_dirty(leaf);
1394         btrfs_release_path(&path);
1395         ret = btrfs_commit_transaction(trans, root);
1396         BUG_ON(ret);
1397 fail:
1398         btrfs_release_path(&path);
1399         return ret;
1400 }
1401
1402 static struct btrfs_root * link_subvol(struct btrfs_root *root,
1403                 const char *base, u64 root_objectid)
1404 {
1405         struct btrfs_trans_handle *trans;
1406         struct btrfs_fs_info *fs_info = root->fs_info;
1407         struct btrfs_root *tree_root = fs_info->tree_root;
1408         struct btrfs_root *new_root = NULL;
1409         struct btrfs_path *path;
1410         struct btrfs_inode_item *inode_item;
1411         struct extent_buffer *leaf;
1412         struct btrfs_key key;
1413         u64 dirid = btrfs_root_dirid(&root->root_item);
1414         u64 index = 2;
1415         char buf[BTRFS_NAME_LEN + 1]; /* for snprintf null */
1416         int len;
1417         int i;
1418         int ret;
1419
1420         len = strlen(base);
1421         if (len < 1 || len > BTRFS_NAME_LEN)
1422                 return NULL;
1423
1424         path = btrfs_alloc_path();
1425         BUG_ON(!path);
1426
1427         key.objectid = dirid;
1428         key.type = BTRFS_DIR_INDEX_KEY;
1429         key.offset = (u64)-1;
1430
1431         ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1432         BUG_ON(ret <= 0);
1433
1434         if (path->slots[0] > 0) {
1435                 path->slots[0]--;
1436                 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1437                 if (key.objectid == dirid && key.type == BTRFS_DIR_INDEX_KEY)
1438                         index = key.offset + 1;
1439         }
1440         btrfs_release_path(path);
1441
1442         trans = btrfs_start_transaction(root, 1);
1443         BUG_ON(!trans);
1444
1445         key.objectid = dirid;
1446         key.offset = 0;
1447         key.type =  BTRFS_INODE_ITEM_KEY;
1448
1449         ret = btrfs_lookup_inode(trans, root, path, &key, 1);
1450         BUG_ON(ret);
1451         leaf = path->nodes[0];
1452         inode_item = btrfs_item_ptr(leaf, path->slots[0],
1453                                     struct btrfs_inode_item);
1454
1455         key.objectid = root_objectid;
1456         key.offset = (u64)-1;
1457         key.type = BTRFS_ROOT_ITEM_KEY;
1458
1459         memcpy(buf, base, len);
1460         for (i = 0; i < 1024; i++) {
1461                 ret = btrfs_insert_dir_item(trans, root, buf, len,
1462                                             dirid, &key, BTRFS_FT_DIR, index);
1463                 if (ret != -EEXIST)
1464                         break;
1465                 len = snprintf(buf, ARRAY_SIZE(buf), "%s%d", base, i);
1466                 if (len < 1 || len > BTRFS_NAME_LEN) {
1467                         ret = -EINVAL;
1468                         break;
1469                 }
1470         }
1471         if (ret)
1472                 goto fail;
1473
1474         btrfs_set_inode_size(leaf, inode_item, len * 2 +
1475                              btrfs_inode_size(leaf, inode_item));
1476         btrfs_mark_buffer_dirty(leaf);
1477         btrfs_release_path(path);
1478
1479         /* add the backref first */
1480         ret = btrfs_add_root_ref(trans, tree_root, root_objectid,
1481                                  BTRFS_ROOT_BACKREF_KEY,
1482                                  root->root_key.objectid,
1483                                  dirid, index, buf, len);
1484         BUG_ON(ret);
1485
1486         /* now add the forward ref */
1487         ret = btrfs_add_root_ref(trans, tree_root, root->root_key.objectid,
1488                                  BTRFS_ROOT_REF_KEY, root_objectid,
1489                                  dirid, index, buf, len);
1490
1491         ret = btrfs_commit_transaction(trans, root);
1492         BUG_ON(ret);
1493
1494         new_root = btrfs_read_fs_root(fs_info, &key);
1495         if (IS_ERR(new_root))
1496                 new_root = NULL;
1497 fail:
1498         btrfs_free_path(path);
1499         return new_root;
1500 }
1501
1502 static int create_chunk_mapping(struct btrfs_trans_handle *trans,
1503                                 struct btrfs_root *root)
1504 {
1505         struct btrfs_fs_info *info = root->fs_info;
1506         struct btrfs_root *chunk_root = info->chunk_root;
1507         struct btrfs_root *extent_root = info->extent_root;
1508         struct btrfs_device *device;
1509         struct btrfs_block_group_cache *cache;
1510         struct btrfs_dev_extent *extent;
1511         struct extent_buffer *leaf;
1512         struct btrfs_chunk chunk;
1513         struct btrfs_key key;
1514         struct btrfs_path path;
1515         u64 cur_start;
1516         u64 total_bytes;
1517         u64 chunk_objectid;
1518         int ret;
1519
1520         btrfs_init_path(&path);
1521
1522         total_bytes = btrfs_super_total_bytes(root->fs_info->super_copy);
1523         chunk_objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
1524
1525         BUG_ON(list_empty(&info->fs_devices->devices));
1526         device = list_entry(info->fs_devices->devices.next,
1527                             struct btrfs_device, dev_list);
1528         BUG_ON(device->devid != info->fs_devices->latest_devid);
1529
1530         /* delete device extent created by make_btrfs */
1531         key.objectid = device->devid;
1532         key.offset = 0;
1533         key.type = BTRFS_DEV_EXTENT_KEY;
1534         ret = btrfs_search_slot(trans, device->dev_root, &key, &path, -1, 1);
1535         if (ret < 0)
1536                 goto err;
1537
1538         BUG_ON(ret > 0);
1539         ret = btrfs_del_item(trans, device->dev_root, &path);
1540         if (ret)
1541                 goto err;
1542         btrfs_release_path(&path);
1543
1544         /* delete chunk item created by make_btrfs */
1545         key.objectid = chunk_objectid;
1546         key.offset = 0;
1547         key.type = BTRFS_CHUNK_ITEM_KEY;
1548         ret = btrfs_search_slot(trans, chunk_root, &key, &path, -1, 1);
1549         if (ret < 0)
1550                 goto err;
1551
1552         BUG_ON(ret > 0);
1553         ret = btrfs_del_item(trans, chunk_root, &path);
1554         if (ret)
1555                 goto err;
1556         btrfs_release_path(&path);
1557
1558         /* for each block group, create device extent and chunk item */
1559         cur_start = 0;
1560         while (cur_start < total_bytes) {
1561                 cache = btrfs_lookup_block_group(root->fs_info, cur_start);
1562                 BUG_ON(!cache);
1563
1564                 /* insert device extent */
1565                 key.objectid = device->devid;
1566                 key.offset = cache->key.objectid;
1567                 key.type = BTRFS_DEV_EXTENT_KEY;
1568                 ret = btrfs_insert_empty_item(trans, device->dev_root, &path,
1569                                               &key, sizeof(*extent));
1570                 if (ret)
1571                         goto err;
1572
1573                 leaf = path.nodes[0];
1574                 extent = btrfs_item_ptr(leaf, path.slots[0],
1575                                         struct btrfs_dev_extent);
1576
1577                 btrfs_set_dev_extent_chunk_tree(leaf, extent,
1578                                                 chunk_root->root_key.objectid);
1579                 btrfs_set_dev_extent_chunk_objectid(leaf, extent,
1580                                                     chunk_objectid);
1581                 btrfs_set_dev_extent_chunk_offset(leaf, extent,
1582                                                   cache->key.objectid);
1583                 btrfs_set_dev_extent_length(leaf, extent, cache->key.offset);
1584                 write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid,
1585                     (unsigned long)btrfs_dev_extent_chunk_tree_uuid(extent),
1586                     BTRFS_UUID_SIZE);
1587                 btrfs_mark_buffer_dirty(leaf);
1588                 btrfs_release_path(&path);
1589
1590                 /* insert chunk item */
1591                 btrfs_set_stack_chunk_length(&chunk, cache->key.offset);
1592                 btrfs_set_stack_chunk_owner(&chunk,
1593                                             extent_root->root_key.objectid);
1594                 btrfs_set_stack_chunk_stripe_len(&chunk, BTRFS_STRIPE_LEN);
1595                 btrfs_set_stack_chunk_type(&chunk, cache->flags);
1596                 btrfs_set_stack_chunk_io_align(&chunk, device->io_align);
1597                 btrfs_set_stack_chunk_io_width(&chunk, device->io_width);
1598                 btrfs_set_stack_chunk_sector_size(&chunk, device->sector_size);
1599                 btrfs_set_stack_chunk_num_stripes(&chunk, 1);
1600                 btrfs_set_stack_chunk_sub_stripes(&chunk, 0);
1601                 btrfs_set_stack_stripe_devid(&chunk.stripe, device->devid);
1602                 btrfs_set_stack_stripe_offset(&chunk.stripe,
1603                                               cache->key.objectid);
1604                 memcpy(&chunk.stripe.dev_uuid, device->uuid, BTRFS_UUID_SIZE);
1605
1606                 key.objectid = chunk_objectid;
1607                 key.offset = cache->key.objectid;
1608                 key.type = BTRFS_CHUNK_ITEM_KEY;
1609
1610                 ret = btrfs_insert_item(trans, chunk_root, &key, &chunk,
1611                                         btrfs_chunk_item_size(1));
1612                 if (ret)
1613                         goto err;
1614
1615                 cur_start = cache->key.objectid + cache->key.offset;
1616         }
1617
1618         device->bytes_used = total_bytes;
1619         ret = btrfs_update_device(trans, device);
1620 err:
1621         btrfs_release_path(&path);
1622         return ret;
1623 }
1624
1625 static int create_subvol(struct btrfs_trans_handle *trans,
1626                          struct btrfs_root *root, u64 root_objectid)
1627 {
1628         struct extent_buffer *tmp;
1629         struct btrfs_root *new_root;
1630         struct btrfs_key key;
1631         struct btrfs_root_item root_item;
1632         int ret;
1633
1634         ret = btrfs_copy_root(trans, root, root->node, &tmp,
1635                               root_objectid);
1636         BUG_ON(ret);
1637
1638         memcpy(&root_item, &root->root_item, sizeof(root_item));
1639         btrfs_set_root_bytenr(&root_item, tmp->start);
1640         btrfs_set_root_level(&root_item, btrfs_header_level(tmp));
1641         btrfs_set_root_generation(&root_item, trans->transid);
1642         free_extent_buffer(tmp);
1643
1644         key.objectid = root_objectid;
1645         key.type = BTRFS_ROOT_ITEM_KEY;
1646         key.offset = trans->transid;
1647         ret = btrfs_insert_root(trans, root->fs_info->tree_root,
1648                                 &key, &root_item);
1649
1650         key.offset = (u64)-1;
1651         new_root = btrfs_read_fs_root(root->fs_info, &key);
1652         BUG_ON(!new_root || IS_ERR(new_root));
1653
1654         ret = btrfs_make_root_dir(trans, new_root, BTRFS_FIRST_FREE_OBJECTID);
1655         BUG_ON(ret);
1656
1657         return 0;
1658 }
1659
1660 static int init_btrfs(struct btrfs_root *root)
1661 {
1662         int ret;
1663         struct btrfs_key location;
1664         struct btrfs_trans_handle *trans;
1665         struct btrfs_fs_info *fs_info = root->fs_info;
1666         struct extent_buffer *tmp;
1667
1668         trans = btrfs_start_transaction(root, 1);
1669         BUG_ON(!trans);
1670         ret = btrfs_make_block_groups(trans, root);
1671         if (ret)
1672                 goto err;
1673         ret = btrfs_fix_block_accounting(trans, root);
1674         if (ret)
1675                 goto err;
1676         ret = create_chunk_mapping(trans, root);
1677         if (ret)
1678                 goto err;
1679         ret = btrfs_make_root_dir(trans, fs_info->tree_root,
1680                                   BTRFS_ROOT_TREE_DIR_OBJECTID);
1681         if (ret)
1682                 goto err;
1683         memcpy(&location, &root->root_key, sizeof(location));
1684         location.offset = (u64)-1;
1685         ret = btrfs_insert_dir_item(trans, fs_info->tree_root, "default", 7,
1686                                 btrfs_super_root_dir(fs_info->super_copy),
1687                                 &location, BTRFS_FT_DIR, 0);
1688         if (ret)
1689                 goto err;
1690         ret = btrfs_insert_inode_ref(trans, fs_info->tree_root, "default", 7,
1691                                 location.objectid,
1692                                 btrfs_super_root_dir(fs_info->super_copy), 0);
1693         if (ret)
1694                 goto err;
1695         btrfs_set_root_dirid(&fs_info->fs_root->root_item,
1696                              BTRFS_FIRST_FREE_OBJECTID);
1697
1698         /* subvol for ext2 image file */
1699         ret = create_subvol(trans, root, EXT2_IMAGE_SUBVOL_OBJECTID);
1700         BUG_ON(ret);
1701         /* subvol for data relocation */
1702         ret = create_subvol(trans, root, BTRFS_DATA_RELOC_TREE_OBJECTID);
1703         BUG_ON(ret);
1704
1705         extent_buffer_get(fs_info->csum_root->node);
1706         ret = __btrfs_cow_block(trans, fs_info->csum_root,
1707                                 fs_info->csum_root->node, NULL, 0, &tmp, 0, 0);
1708         BUG_ON(ret);
1709         free_extent_buffer(tmp);
1710
1711         ret = btrfs_commit_transaction(trans, root);
1712         BUG_ON(ret);
1713 err:
1714         return ret;
1715 }
1716
1717 /*
1718  * Migrate super block to its default position and zero 0 ~ 16k
1719  */
1720 static int migrate_super_block(int fd, u64 old_bytenr, u32 sectorsize)
1721 {
1722         int ret;
1723         struct extent_buffer *buf;
1724         struct btrfs_super_block *super;
1725         u32 len;
1726         u32 bytenr;
1727
1728         BUG_ON(sectorsize < sizeof(*super));
1729         buf = malloc(sizeof(*buf) + sectorsize);
1730         if (!buf)
1731                 return -ENOMEM;
1732
1733         buf->len = sectorsize;
1734         ret = pread(fd, buf->data, sectorsize, old_bytenr);
1735         if (ret != sectorsize)
1736                 goto fail;
1737
1738         super = (struct btrfs_super_block *)buf->data;
1739         BUG_ON(btrfs_super_bytenr(super) != old_bytenr);
1740         btrfs_set_super_bytenr(super, BTRFS_SUPER_INFO_OFFSET);
1741
1742         csum_tree_block_size(buf, BTRFS_CRC32_SIZE, 0);
1743         ret = pwrite(fd, buf->data, sectorsize, BTRFS_SUPER_INFO_OFFSET);
1744         if (ret != sectorsize)
1745                 goto fail;
1746
1747         ret = fsync(fd);
1748         if (ret)
1749                 goto fail;
1750
1751         memset(buf->data, 0, sectorsize);
1752         for (bytenr = 0; bytenr < BTRFS_SUPER_INFO_OFFSET; ) {
1753                 len = BTRFS_SUPER_INFO_OFFSET - bytenr;
1754                 if (len > sectorsize)
1755                         len = sectorsize;
1756                 ret = pwrite(fd, buf->data, len, bytenr);
1757                 if (ret != len) {
1758                         fprintf(stderr, "unable to zero fill device\n");
1759                         break;
1760                 }
1761                 bytenr += len;
1762         }
1763         ret = 0;
1764         fsync(fd);
1765 fail:
1766         free(buf);
1767         if (ret > 0)
1768                 ret = -1;
1769         return ret;
1770 }
1771
1772 static int prepare_system_chunk_sb(struct btrfs_super_block *super)
1773 {
1774         struct btrfs_chunk *chunk;
1775         struct btrfs_disk_key *key;
1776         u32 sectorsize = btrfs_super_sectorsize(super);
1777
1778         key = (struct btrfs_disk_key *)(super->sys_chunk_array);
1779         chunk = (struct btrfs_chunk *)(super->sys_chunk_array +
1780                                        sizeof(struct btrfs_disk_key));
1781
1782         btrfs_set_disk_key_objectid(key, BTRFS_FIRST_CHUNK_TREE_OBJECTID);
1783         btrfs_set_disk_key_type(key, BTRFS_CHUNK_ITEM_KEY);
1784         btrfs_set_disk_key_offset(key, 0);
1785
1786         btrfs_set_stack_chunk_length(chunk, btrfs_super_total_bytes(super));
1787         btrfs_set_stack_chunk_owner(chunk, BTRFS_EXTENT_TREE_OBJECTID);
1788         btrfs_set_stack_chunk_stripe_len(chunk, BTRFS_STRIPE_LEN);
1789         btrfs_set_stack_chunk_type(chunk, BTRFS_BLOCK_GROUP_SYSTEM);
1790         btrfs_set_stack_chunk_io_align(chunk, sectorsize);
1791         btrfs_set_stack_chunk_io_width(chunk, sectorsize);
1792         btrfs_set_stack_chunk_sector_size(chunk, sectorsize);
1793         btrfs_set_stack_chunk_num_stripes(chunk, 1);
1794         btrfs_set_stack_chunk_sub_stripes(chunk, 0);
1795         chunk->stripe.devid = super->dev_item.devid;
1796         btrfs_set_stack_stripe_offset(&chunk->stripe, 0);
1797         memcpy(chunk->stripe.dev_uuid, super->dev_item.uuid, BTRFS_UUID_SIZE);
1798         btrfs_set_super_sys_array_size(super, sizeof(*key) + sizeof(*chunk));
1799         return 0;
1800 }
1801
1802 static int prepare_system_chunk(int fd, u64 sb_bytenr)
1803 {
1804         int ret;
1805         struct extent_buffer *buf;
1806         struct btrfs_super_block *super;
1807
1808         BUG_ON(BTRFS_SUPER_INFO_SIZE < sizeof(*super));
1809         buf = malloc(sizeof(*buf) + BTRFS_SUPER_INFO_SIZE);
1810         if (!buf)
1811                 return -ENOMEM;
1812
1813         buf->len = BTRFS_SUPER_INFO_SIZE;
1814         ret = pread(fd, buf->data, BTRFS_SUPER_INFO_SIZE, sb_bytenr);
1815         if (ret != BTRFS_SUPER_INFO_SIZE)
1816                 goto fail;
1817
1818         super = (struct btrfs_super_block *)buf->data;
1819         BUG_ON(btrfs_super_bytenr(super) != sb_bytenr);
1820         BUG_ON(btrfs_super_num_devices(super) != 1);
1821
1822         ret = prepare_system_chunk_sb(super);
1823         if (ret)
1824                 goto fail;
1825
1826         csum_tree_block_size(buf, BTRFS_CRC32_SIZE, 0);
1827         ret = pwrite(fd, buf->data, BTRFS_SUPER_INFO_SIZE, sb_bytenr);
1828         if (ret != BTRFS_SUPER_INFO_SIZE)
1829                 goto fail;
1830
1831         ret = 0;
1832 fail:
1833         free(buf);
1834         if (ret > 0)
1835                 ret = -1;
1836         return ret;
1837 }
1838
1839 static int relocate_one_reference(struct btrfs_trans_handle *trans,
1840                                   struct btrfs_root *root,
1841                                   u64 extent_start, u64 extent_size,
1842                                   struct btrfs_key *extent_key,
1843                                   struct extent_io_tree *reloc_tree)
1844 {
1845         struct extent_buffer *leaf;
1846         struct btrfs_file_extent_item *fi;
1847         struct btrfs_key key;
1848         struct btrfs_path path;
1849         struct btrfs_inode_item inode;
1850         struct blk_iterate_data data;
1851         u64 bytenr;
1852         u64 num_bytes;
1853         u64 cur_offset;
1854         u64 new_pos;
1855         u64 nbytes;
1856         u64 sector_end;
1857         u32 sectorsize = root->sectorsize;
1858         unsigned long ptr;
1859         int datacsum;
1860         int fd;
1861         int ret;
1862
1863         btrfs_init_path(&path);
1864         ret = btrfs_search_slot(trans, root, extent_key, &path, -1, 1);
1865         if (ret)
1866                 goto fail;
1867
1868         leaf = path.nodes[0];
1869         fi = btrfs_item_ptr(leaf, path.slots[0],
1870                             struct btrfs_file_extent_item);
1871         BUG_ON(btrfs_file_extent_offset(leaf, fi) > 0);
1872         if (extent_start != btrfs_file_extent_disk_bytenr(leaf, fi) ||
1873             extent_size != btrfs_file_extent_disk_num_bytes(leaf, fi)) {
1874                 ret = 1;
1875                 goto fail;
1876         }
1877
1878         bytenr = extent_start + btrfs_file_extent_offset(leaf, fi);
1879         num_bytes = btrfs_file_extent_num_bytes(leaf, fi);
1880
1881         ret = btrfs_del_item(trans, root, &path);
1882         if (ret)
1883                 goto fail;
1884
1885         ret = btrfs_free_extent(trans, root, extent_start, extent_size, 0,
1886                                 root->root_key.objectid,
1887                                 extent_key->objectid, extent_key->offset);
1888         if (ret)
1889                 goto fail;
1890
1891         btrfs_release_path(&path);
1892
1893         key.objectid = extent_key->objectid;
1894         key.offset = 0;
1895         key.type =  BTRFS_INODE_ITEM_KEY;
1896         ret = btrfs_lookup_inode(trans, root, &path, &key, 0);
1897         if (ret)
1898                 goto fail;
1899
1900         leaf = path.nodes[0];
1901         ptr = btrfs_item_ptr_offset(leaf, path.slots[0]);
1902         read_extent_buffer(leaf, &inode, ptr, sizeof(inode));
1903         btrfs_release_path(&path);
1904
1905         BUG_ON(num_bytes & (sectorsize - 1));
1906         nbytes = btrfs_stack_inode_nbytes(&inode) - num_bytes;
1907         btrfs_set_stack_inode_nbytes(&inode, nbytes);
1908         datacsum = !(btrfs_stack_inode_flags(&inode) & BTRFS_INODE_NODATASUM);
1909
1910         data = (struct blk_iterate_data) {
1911                 .trans          = trans,
1912                 .root           = root,
1913                 .inode          = &inode,
1914                 .objectid       = extent_key->objectid,
1915                 .first_block    = extent_key->offset / sectorsize,
1916                 .disk_block     = 0,
1917                 .num_blocks     = 0,
1918                 .boundary       = (u64)-1,
1919                 .checksum       = datacsum,
1920                 .errcode        = 0,
1921         };
1922
1923         cur_offset = extent_key->offset;
1924         while (num_bytes > 0) {
1925                 sector_end = bytenr + sectorsize - 1;
1926                 if (test_range_bit(reloc_tree, bytenr, sector_end,
1927                                    EXTENT_LOCKED, 1)) {
1928                         ret = get_state_private(reloc_tree, bytenr, &new_pos);
1929                         BUG_ON(ret);
1930                 } else {
1931                         ret = custom_alloc_extent(root, sectorsize, 0, &key);
1932                         if (ret)
1933                                 goto fail;
1934                         new_pos = key.objectid;
1935
1936                         if (cur_offset == extent_key->offset) {
1937                                 fd = root->fs_info->fs_devices->latest_bdev;
1938                                 readahead(fd, bytenr, num_bytes);
1939                         }
1940                         ret = copy_disk_extent(root, new_pos, bytenr,
1941                                                sectorsize);
1942                         if (ret)
1943                                 goto fail;
1944                         ret = set_extent_bits(reloc_tree, bytenr, sector_end,
1945                                               EXTENT_LOCKED, GFP_NOFS);
1946                         BUG_ON(ret);
1947                         ret = set_state_private(reloc_tree, bytenr, new_pos);
1948                         BUG_ON(ret);
1949                 }
1950
1951                 ret = block_iterate_proc(NULL, new_pos / sectorsize,
1952                                          cur_offset / sectorsize, &data);
1953                 if (ret & BLOCK_ABORT) {
1954                         ret = data.errcode;
1955                         goto fail;
1956                 }
1957
1958                 cur_offset += sectorsize;
1959                 bytenr += sectorsize;
1960                 num_bytes -= sectorsize;
1961         }
1962
1963         if (data.num_blocks > 0) {
1964                 ret = record_file_blocks(trans, root,
1965                                          extent_key->objectid, &inode,
1966                                          data.first_block, data.disk_block,
1967                                          data.num_blocks, datacsum);
1968                 if (ret)
1969                         goto fail;
1970         }
1971
1972         key.objectid = extent_key->objectid;
1973         key.offset = 0;
1974         key.type =  BTRFS_INODE_ITEM_KEY;
1975         ret = btrfs_lookup_inode(trans, root, &path, &key, 1);
1976         if (ret)
1977                 goto fail;
1978
1979         leaf = path.nodes[0];
1980         ptr = btrfs_item_ptr_offset(leaf, path.slots[0]);
1981         write_extent_buffer(leaf, &inode, ptr, sizeof(inode));
1982         btrfs_mark_buffer_dirty(leaf);
1983         btrfs_release_path(&path);
1984
1985 fail:
1986         btrfs_release_path(&path);
1987         return ret;
1988 }
1989
1990 static int relocate_extents_range(struct btrfs_root *fs_root,
1991                                   struct btrfs_root *ext2_root,
1992                                   u64 start_byte, u64 end_byte)
1993 {
1994         struct btrfs_fs_info *info = fs_root->fs_info;
1995         struct btrfs_root *extent_root = info->extent_root;
1996         struct btrfs_root *cur_root = NULL;
1997         struct btrfs_trans_handle *trans;
1998         struct btrfs_extent_data_ref *dref;
1999         struct btrfs_extent_inline_ref *iref;
2000         struct btrfs_extent_item *ei;
2001         struct extent_buffer *leaf;
2002         struct btrfs_key key;
2003         struct btrfs_key extent_key;
2004         struct btrfs_path path;
2005         struct extent_io_tree reloc_tree;
2006         unsigned long ptr;
2007         unsigned long end;
2008         u64 cur_byte;
2009         u64 num_bytes;
2010         u64 ref_root;
2011         u64 num_extents;
2012         int pass = 0;
2013         int ret;
2014
2015         btrfs_init_path(&path);
2016         extent_io_tree_init(&reloc_tree);
2017
2018         key.objectid = start_byte;
2019         key.offset = 0;
2020         key.type = BTRFS_EXTENT_ITEM_KEY;
2021         ret = btrfs_search_slot(NULL, extent_root, &key, &path, 0, 0);
2022         if (ret < 0)
2023                 goto fail;
2024         if (ret > 0) {
2025                 ret = btrfs_previous_item(extent_root, &path, 0,
2026                                           BTRFS_EXTENT_ITEM_KEY);
2027                 if (ret < 0)
2028                         goto fail;
2029                 if (ret == 0) {
2030                         leaf = path.nodes[0];
2031                         btrfs_item_key_to_cpu(leaf, &key, path.slots[0]);
2032                         if (key.objectid + key.offset > start_byte)
2033                                 start_byte = key.objectid;
2034                 }
2035         }
2036         btrfs_release_path(&path);
2037 again:
2038         cur_root = (pass % 2 == 0) ? ext2_root : fs_root;
2039         num_extents = 0;
2040
2041         trans = btrfs_start_transaction(cur_root, 1);
2042         BUG_ON(!trans);
2043
2044         cur_byte = start_byte;
2045         while (1) {
2046                 key.objectid = cur_byte;
2047                 key.offset = 0;
2048                 key.type = BTRFS_EXTENT_ITEM_KEY;
2049                 ret = btrfs_search_slot(trans, extent_root,
2050                                         &key, &path, 0, 0);
2051                 if (ret < 0)
2052                         goto fail;
2053 next:
2054                 leaf = path.nodes[0];
2055                 if (path.slots[0] >= btrfs_header_nritems(leaf)) {
2056                         ret = btrfs_next_leaf(extent_root, &path);
2057                         if (ret < 0)
2058                                 goto fail;
2059                         if (ret > 0)
2060                                 break;
2061                         leaf = path.nodes[0];
2062                 }
2063
2064                 btrfs_item_key_to_cpu(leaf, &key, path.slots[0]);
2065                 if (key.objectid < cur_byte ||
2066                     key.type != BTRFS_EXTENT_ITEM_KEY) {
2067                         path.slots[0]++;
2068                         goto next;
2069                 }
2070                 if (key.objectid >= end_byte)
2071                         break;
2072
2073                 num_extents++;
2074
2075                 cur_byte = key.objectid;
2076                 num_bytes = key.offset;
2077                 ei = btrfs_item_ptr(leaf, path.slots[0],
2078                                     struct btrfs_extent_item);
2079                 BUG_ON(!(btrfs_extent_flags(leaf, ei) &
2080                          BTRFS_EXTENT_FLAG_DATA));
2081
2082                 ptr = btrfs_item_ptr_offset(leaf, path.slots[0]);
2083                 end = ptr + btrfs_item_size_nr(leaf, path.slots[0]);
2084
2085                 ptr += sizeof(struct btrfs_extent_item);
2086
2087                 while (ptr < end) {
2088                         iref = (struct btrfs_extent_inline_ref *)ptr;
2089                         key.type = btrfs_extent_inline_ref_type(leaf, iref);
2090                         BUG_ON(key.type != BTRFS_EXTENT_DATA_REF_KEY);
2091                         dref = (struct btrfs_extent_data_ref *)(&iref->offset);
2092                         ref_root = btrfs_extent_data_ref_root(leaf, dref);
2093                         extent_key.objectid =
2094                                 btrfs_extent_data_ref_objectid(leaf, dref);
2095                         extent_key.offset =
2096                                 btrfs_extent_data_ref_offset(leaf, dref);
2097                         extent_key.type = BTRFS_EXTENT_DATA_KEY;
2098                         BUG_ON(btrfs_extent_data_ref_count(leaf, dref) != 1);
2099
2100                         if (ref_root == cur_root->root_key.objectid)
2101                                 break;
2102
2103                         ptr += btrfs_extent_inline_ref_size(key.type);
2104                 }
2105
2106                 if (ptr >= end) {
2107                         path.slots[0]++;
2108                         goto next;
2109                 }
2110
2111                 ret = relocate_one_reference(trans, cur_root, cur_byte,
2112                                              num_bytes, &extent_key,
2113                                              &reloc_tree);
2114                 if (ret < 0)
2115                         goto fail;
2116
2117                 cur_byte += num_bytes;
2118                 btrfs_release_path(&path);
2119
2120                 if (trans->blocks_used >= 4096) {
2121                         ret = btrfs_commit_transaction(trans, cur_root);
2122                         BUG_ON(ret);
2123                         trans = btrfs_start_transaction(cur_root, 1);
2124                         BUG_ON(!trans);
2125                 }
2126         }
2127         btrfs_release_path(&path);
2128
2129         ret = btrfs_commit_transaction(trans, cur_root);
2130         BUG_ON(ret);
2131
2132         if (num_extents > 0 && pass++ < 16)
2133                 goto again;
2134
2135         ret = (num_extents > 0) ? -1 : 0;
2136 fail:
2137         btrfs_release_path(&path);
2138         extent_io_tree_cleanup(&reloc_tree);
2139         return ret;
2140 }
2141
2142 /*
2143  * relocate data in system chunk
2144  */
2145 static int cleanup_sys_chunk(struct btrfs_root *fs_root,
2146                              struct btrfs_root *ext2_root)
2147 {
2148         struct btrfs_block_group_cache *cache;
2149         int i, ret = 0;
2150         u64 offset = 0;
2151         u64 end_byte;
2152
2153         while(1) {
2154                 cache = btrfs_lookup_block_group(fs_root->fs_info, offset);
2155                 if (!cache)
2156                         break;
2157
2158                 end_byte = cache->key.objectid + cache->key.offset;
2159                 if (cache->flags & BTRFS_BLOCK_GROUP_SYSTEM) {
2160                         ret = relocate_extents_range(fs_root, ext2_root,
2161                                                      cache->key.objectid,
2162                                                      end_byte);
2163                         if (ret)
2164                                 goto fail;
2165                 }
2166                 offset = end_byte;
2167         }
2168         for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
2169                 offset = btrfs_sb_offset(i);
2170                 offset &= ~((u64)BTRFS_STRIPE_LEN - 1);
2171
2172                 ret = relocate_extents_range(fs_root, ext2_root,
2173                                              offset, offset + BTRFS_STRIPE_LEN);
2174                 if (ret)
2175                         goto fail;
2176         }
2177         ret = 0;
2178 fail:
2179         return ret;
2180 }
2181
2182 static int fixup_chunk_mapping(struct btrfs_root *root)
2183 {
2184         struct btrfs_trans_handle *trans;
2185         struct btrfs_fs_info *info = root->fs_info;
2186         struct btrfs_root *chunk_root = info->chunk_root;
2187         struct extent_buffer *leaf;
2188         struct btrfs_key key;
2189         struct btrfs_path path;
2190         struct btrfs_chunk chunk;
2191         unsigned long ptr;
2192         u32 size;
2193         u64 type;
2194         int ret;
2195
2196         btrfs_init_path(&path);
2197
2198         trans = btrfs_start_transaction(root, 1);
2199         BUG_ON(!trans);
2200
2201         /*
2202          * recow the whole chunk tree. this will move all chunk tree blocks
2203          * into system block group.
2204          */
2205         memset(&key, 0, sizeof(key));
2206         while (1) {
2207                 ret = btrfs_search_slot(trans, chunk_root, &key, &path, 0, 1);
2208                 if (ret < 0)
2209                         goto err;
2210
2211                 ret = btrfs_next_leaf(chunk_root, &path);
2212                 if (ret < 0)
2213                         goto err;
2214                 if (ret > 0)
2215                         break;
2216
2217                 btrfs_item_key_to_cpu(path.nodes[0], &key, path.slots[0]);
2218                 btrfs_release_path(&path);
2219         }
2220         btrfs_release_path(&path);
2221
2222         /* fixup the system chunk array in super block */
2223         btrfs_set_super_sys_array_size(info->super_copy, 0);
2224
2225         key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
2226         key.offset = 0;
2227         key.type = BTRFS_CHUNK_ITEM_KEY;
2228
2229         ret = btrfs_search_slot(trans, chunk_root, &key, &path, 0, 0);
2230         if (ret < 0)
2231                 goto err;
2232         BUG_ON(ret != 0);
2233         while(1) {
2234                 leaf = path.nodes[0];
2235                 if (path.slots[0] >= btrfs_header_nritems(leaf)) {
2236                         ret = btrfs_next_leaf(chunk_root, &path);
2237                         if (ret < 0)
2238                                 goto err;
2239                         if (ret > 0)
2240                                 break;
2241                         leaf = path.nodes[0];
2242                 }
2243                 btrfs_item_key_to_cpu(leaf, &key, path.slots[0]);
2244                 if (key.type != BTRFS_CHUNK_ITEM_KEY)
2245                         goto next;
2246
2247                 ptr = btrfs_item_ptr_offset(leaf, path.slots[0]);
2248                 size = btrfs_item_size_nr(leaf, path.slots[0]);
2249                 BUG_ON(size != sizeof(chunk));
2250                 read_extent_buffer(leaf, &chunk, ptr, size);
2251                 type = btrfs_stack_chunk_type(&chunk);
2252
2253                 if (!(type & BTRFS_BLOCK_GROUP_SYSTEM))
2254                         goto next;
2255
2256                 ret = btrfs_add_system_chunk(trans, chunk_root, &key,
2257                                              &chunk, size);
2258                 if (ret)
2259                         goto err;
2260 next:
2261                 path.slots[0]++;
2262         }
2263
2264         ret = btrfs_commit_transaction(trans, root);
2265         BUG_ON(ret);
2266 err:
2267         btrfs_release_path(&path);
2268         return ret;
2269 }
2270
2271 static int do_convert(const char *devname, int datacsum, int packing, int noxattr,
2272                 u32 nodesize, int copylabel, const char *fslabel, int progress)
2273 {
2274         int i, ret, blocks_per_node;
2275         int fd = -1;
2276         u32 blocksize;
2277         u64 blocks[7];
2278         u64 total_bytes;
2279         u64 super_bytenr;
2280         ext2_filsys ext2_fs;
2281         struct btrfs_root *root;
2282         struct btrfs_root *ext2_root;
2283         struct task_ctx ctx;
2284
2285         ret = open_ext2fs(devname, &ext2_fs);
2286         if (ret) {
2287                 fprintf(stderr, "unable to open the Ext2fs\n");
2288                 goto fail;
2289         }
2290         blocksize = ext2_fs->blocksize;
2291         total_bytes = (u64)ext2_fs->super->s_blocks_count * blocksize;
2292         if (blocksize < 4096) {
2293                 fprintf(stderr, "block size is too small\n");
2294                 goto fail;
2295         }
2296         if (!(ext2_fs->super->s_feature_incompat &
2297               EXT2_FEATURE_INCOMPAT_FILETYPE)) {
2298                 fprintf(stderr, "filetype feature is missing\n");
2299                 goto fail;
2300         }
2301         if (btrfs_check_nodesize(nodesize, blocksize))
2302                 goto fail;
2303         blocks_per_node = nodesize / blocksize;
2304         ret = -blocks_per_node;
2305         for (i = 0; i < 7; i++) {
2306                 if (nodesize == blocksize)
2307                         ret = ext2_alloc_block(ext2_fs, 0, blocks + i);
2308                 else
2309                         ret = ext2_alloc_block_range(ext2_fs,
2310                                         ret + blocks_per_node, blocks_per_node,
2311                                         blocks + i);
2312                 if (ret) {
2313                         fprintf(stderr, "not enough free space\n");
2314                         goto fail;
2315                 }
2316                 blocks[i] *= blocksize;
2317         }
2318         super_bytenr = blocks[0];
2319         fd = open(devname, O_RDWR);
2320         if (fd < 0) {
2321                 fprintf(stderr, "unable to open %s\n", devname);
2322                 goto fail;
2323         }
2324         ret = make_btrfs(fd, devname, ext2_fs->super->s_volume_name,
2325                          NULL, blocks, total_bytes, nodesize,
2326                          blocksize, blocksize, 0);
2327         if (ret) {
2328                 fprintf(stderr, "unable to create initial ctree: %s\n",
2329                         strerror(-ret));
2330                 goto fail;
2331         }
2332         /* create a system chunk that maps the whole device */
2333         ret = prepare_system_chunk(fd, super_bytenr);
2334         if (ret) {
2335                 fprintf(stderr, "unable to update system chunk\n");
2336                 goto fail;
2337         }
2338         root = open_ctree_fd(fd, devname, super_bytenr, OPEN_CTREE_WRITES);
2339         if (!root) {
2340                 fprintf(stderr, "unable to open ctree\n");
2341                 goto fail;
2342         }
2343         ret = cache_free_extents(root, ext2_fs);
2344         if (ret) {
2345                 fprintf(stderr, "error during cache_free_extents %d\n", ret);
2346                 goto fail;
2347         }
2348         root->fs_info->extent_ops = &extent_ops;
2349         /* recover block allocation bitmap */
2350         for (i = 0; i < 7; i++) {
2351                 blocks[i] /= blocksize;
2352                 if (nodesize == blocksize)
2353                         ext2_free_block(ext2_fs, blocks[i]);
2354                 else
2355                         ext2_free_block_range(ext2_fs, blocks[i],
2356                                         blocks_per_node);
2357         }
2358         ret = init_btrfs(root);
2359         if (ret) {
2360                 fprintf(stderr, "unable to setup the root tree\n");
2361                 goto fail;
2362         }
2363         printf("creating btrfs metadata.\n");
2364         ctx.max_copy_inodes = (ext2_fs->super->s_inodes_count
2365                         - ext2_fs->super->s_free_inodes_count);
2366         ctx.cur_copy_inodes = 0;
2367
2368         if (progress) {
2369                 ctx.info = task_init(print_copied_inodes, after_copied_inodes, &ctx);
2370                 task_start(ctx.info);
2371         }
2372         ret = copy_inodes(root, ext2_fs, datacsum, packing, noxattr, &ctx);
2373         if (ret) {
2374                 fprintf(stderr, "error during copy_inodes %d\n", ret);
2375                 goto fail;
2376         }
2377         if (progress) {
2378                 task_stop(ctx.info);
2379                 task_deinit(ctx.info);
2380         }
2381         printf("creating ext2fs image file.\n");
2382         ext2_root = link_subvol(root, "ext2_saved", EXT2_IMAGE_SUBVOL_OBJECTID);
2383         if (!ext2_root) {
2384                 fprintf(stderr, "unable to create subvol\n");
2385                 goto fail;
2386         }
2387         ret = create_ext2_image(ext2_root, ext2_fs, "image", datacsum);
2388         if (ret) {
2389                 fprintf(stderr, "error during create_ext2_image %d\n", ret);
2390                 goto fail;
2391         }
2392         memset(root->fs_info->super_copy->label, 0, BTRFS_LABEL_SIZE);
2393         if (copylabel == 1) {
2394                 strncpy(root->fs_info->super_copy->label,
2395                                 ext2_fs->super->s_volume_name, 16);
2396                 fprintf(stderr, "copy label '%s'\n",
2397                                 root->fs_info->super_copy->label);
2398         } else if (copylabel == -1) {
2399                 strncpy(root->fs_info->super_copy->label, fslabel, BTRFS_LABEL_SIZE);
2400                 fprintf(stderr, "set label to '%s'\n", fslabel);
2401         }
2402
2403         printf("cleaning up system chunk.\n");
2404         ret = cleanup_sys_chunk(root, ext2_root);
2405         if (ret) {
2406                 fprintf(stderr, "error during cleanup_sys_chunk %d\n", ret);
2407                 goto fail;
2408         }
2409         ret = close_ctree(root);
2410         if (ret) {
2411                 fprintf(stderr, "error during close_ctree %d\n", ret);
2412                 goto fail;
2413         }
2414         close_ext2fs(ext2_fs);
2415
2416         /*
2417          * If this step succeed, we get a mountable btrfs. Otherwise
2418          * the ext2fs is left unchanged.
2419          */
2420         ret = migrate_super_block(fd, super_bytenr, blocksize);
2421         if (ret) {
2422                 fprintf(stderr, "unable to migrate super block\n");
2423                 goto fail;
2424         }
2425
2426         root = open_ctree_fd(fd, devname, 0, OPEN_CTREE_WRITES);
2427         if (!root) {
2428                 fprintf(stderr, "unable to open ctree\n");
2429                 goto fail;
2430         }
2431         /* move chunk tree into system chunk. */
2432         ret = fixup_chunk_mapping(root);
2433         if (ret) {
2434                 fprintf(stderr, "error during fixup_chunk_tree\n");
2435                 goto fail;
2436         }
2437         ret = close_ctree(root);
2438         close(fd);
2439
2440         printf("conversion complete.\n");
2441         return 0;
2442 fail:
2443         if (fd != -1)
2444                 close(fd);
2445         fprintf(stderr, "conversion aborted.\n");
2446         return -1;
2447 }
2448
2449 static int may_rollback(struct btrfs_root *root)
2450 {
2451         struct btrfs_fs_info *info = root->fs_info;
2452         struct btrfs_multi_bio *multi = NULL;
2453         u64 bytenr;
2454         u64 length;
2455         u64 physical;
2456         u64 total_bytes;
2457         int num_stripes;
2458         int ret;
2459
2460         if (btrfs_super_num_devices(info->super_copy) != 1)
2461                 goto fail;
2462
2463         bytenr = BTRFS_SUPER_INFO_OFFSET;
2464         total_bytes = btrfs_super_total_bytes(root->fs_info->super_copy);
2465
2466         while (1) {
2467                 ret = btrfs_map_block(&info->mapping_tree, WRITE, bytenr,
2468                                       &length, &multi, 0, NULL);
2469                 if (ret) {
2470                         if (ret == -ENOENT) {
2471                                 /* removed block group at the tail */
2472                                 if (length == (u64)-1)
2473                                         break;
2474
2475                                 /* removed block group in the middle */
2476                                 goto next;
2477                         }
2478                         goto fail;
2479                 }
2480
2481                 num_stripes = multi->num_stripes;
2482                 physical = multi->stripes[0].physical;
2483                 kfree(multi);
2484
2485                 if (num_stripes != 1 || physical != bytenr)
2486                         goto fail;
2487 next:
2488                 bytenr += length;
2489                 if (bytenr >= total_bytes)
2490                         break;
2491         }
2492         return 0;
2493 fail:
2494         return -1;
2495 }
2496
2497 static int do_rollback(const char *devname)
2498 {
2499         int fd = -1;
2500         int ret;
2501         int i;
2502         struct btrfs_root *root;
2503         struct btrfs_root *ext2_root;
2504         struct btrfs_root *chunk_root;
2505         struct btrfs_dir_item *dir;
2506         struct btrfs_inode_item *inode;
2507         struct btrfs_file_extent_item *fi;
2508         struct btrfs_trans_handle *trans;
2509         struct extent_buffer *leaf;
2510         struct btrfs_block_group_cache *cache1;
2511         struct btrfs_block_group_cache *cache2;
2512         struct btrfs_key key;
2513         struct btrfs_path path;
2514         struct extent_io_tree io_tree;
2515         char *buf = NULL;
2516         char *name;
2517         u64 bytenr;
2518         u64 num_bytes;
2519         u64 root_dir;
2520         u64 objectid;
2521         u64 offset;
2522         u64 start;
2523         u64 end;
2524         u64 sb_bytenr;
2525         u64 first_free;
2526         u64 total_bytes;
2527         u32 sectorsize;
2528
2529         extent_io_tree_init(&io_tree);
2530
2531         fd = open(devname, O_RDWR);
2532         if (fd < 0) {
2533                 fprintf(stderr, "unable to open %s\n", devname);
2534                 goto fail;
2535         }
2536         root = open_ctree_fd(fd, devname, 0, OPEN_CTREE_WRITES);
2537         if (!root) {
2538                 fprintf(stderr, "unable to open ctree\n");
2539                 goto fail;
2540         }
2541         ret = may_rollback(root);
2542         if (ret < 0) {
2543                 fprintf(stderr, "unable to do rollback\n");
2544                 goto fail;
2545         }
2546
2547         sectorsize = root->sectorsize;
2548         buf = malloc(sectorsize);
2549         if (!buf) {
2550                 fprintf(stderr, "unable to allocate memory\n");
2551                 goto fail;
2552         }
2553
2554         btrfs_init_path(&path);
2555
2556         key.objectid = EXT2_IMAGE_SUBVOL_OBJECTID;
2557         key.type = BTRFS_ROOT_ITEM_KEY;
2558         key.offset = (u64)-1;
2559         ext2_root = btrfs_read_fs_root(root->fs_info, &key);
2560         if (!ext2_root || IS_ERR(ext2_root)) {
2561                 fprintf(stderr, "unable to open subvol %llu\n",
2562                         (unsigned long long)key.objectid);
2563                 goto fail;
2564         }
2565
2566         name = "image";
2567         root_dir = btrfs_root_dirid(&root->root_item);
2568         dir = btrfs_lookup_dir_item(NULL, ext2_root, &path,
2569                                    root_dir, name, strlen(name), 0);
2570         if (!dir || IS_ERR(dir)) {
2571                 fprintf(stderr, "unable to find file %s\n", name);
2572                 goto fail;
2573         }
2574         leaf = path.nodes[0];
2575         btrfs_dir_item_key_to_cpu(leaf, dir, &key);
2576         btrfs_release_path(&path);
2577
2578         objectid = key.objectid;
2579
2580         ret = btrfs_lookup_inode(NULL, ext2_root, &path, &key, 0);
2581         if (ret) {
2582                 fprintf(stderr, "unable to find inode item\n");
2583                 goto fail;
2584         }
2585         leaf = path.nodes[0];
2586         inode = btrfs_item_ptr(leaf, path.slots[0], struct btrfs_inode_item);
2587         total_bytes = btrfs_inode_size(leaf, inode);
2588         btrfs_release_path(&path);
2589
2590         key.objectid = objectid;
2591         key.offset = 0;
2592         btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY);
2593         ret = btrfs_search_slot(NULL, ext2_root, &key, &path, 0, 0);
2594         if (ret != 0) {
2595                 fprintf(stderr, "unable to find first file extent\n");
2596                 btrfs_release_path(&path);
2597                 goto fail;
2598         }
2599
2600         /* build mapping tree for the relocated blocks */
2601         for (offset = 0; offset < total_bytes; ) {
2602                 leaf = path.nodes[0];
2603                 if (path.slots[0] >= btrfs_header_nritems(leaf)) {
2604                         ret = btrfs_next_leaf(root, &path);
2605                         if (ret != 0)
2606                                 break;  
2607                         continue;
2608                 }
2609
2610                 btrfs_item_key_to_cpu(leaf, &key, path.slots[0]);
2611                 if (key.objectid != objectid || key.offset != offset ||
2612                     btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
2613                         break;
2614
2615                 fi = btrfs_item_ptr(leaf, path.slots[0],
2616                                     struct btrfs_file_extent_item);
2617                 if (btrfs_file_extent_type(leaf, fi) != BTRFS_FILE_EXTENT_REG)
2618                         break;
2619                 if (btrfs_file_extent_compression(leaf, fi) ||
2620                     btrfs_file_extent_encryption(leaf, fi) ||
2621                     btrfs_file_extent_other_encoding(leaf, fi))
2622                         break;
2623
2624                 bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
2625                 /* skip holes and direct mapped extents */
2626                 if (bytenr == 0 || bytenr == offset)
2627                         goto next_extent;
2628
2629                 bytenr += btrfs_file_extent_offset(leaf, fi);
2630                 num_bytes = btrfs_file_extent_num_bytes(leaf, fi);
2631
2632                 cache1 = btrfs_lookup_block_group(root->fs_info, offset);
2633                 cache2 =  btrfs_lookup_block_group(root->fs_info,
2634                                                    offset + num_bytes - 1);
2635                 if (!cache1 || cache1 != cache2 ||
2636                     (!(cache1->flags & BTRFS_BLOCK_GROUP_SYSTEM) &&
2637                      !intersect_with_sb(offset, num_bytes)))
2638                         break;
2639
2640                 set_extent_bits(&io_tree, offset, offset + num_bytes - 1,
2641                                 EXTENT_LOCKED, GFP_NOFS);
2642                 set_state_private(&io_tree, offset, bytenr);
2643 next_extent:
2644                 offset += btrfs_file_extent_num_bytes(leaf, fi);
2645                 path.slots[0]++;
2646         }
2647         btrfs_release_path(&path);
2648
2649         if (offset < total_bytes) {
2650                 fprintf(stderr, "unable to build extent mapping\n");
2651                 goto fail;
2652         }
2653
2654         first_free = BTRFS_SUPER_INFO_OFFSET + 2 * sectorsize - 1;
2655         first_free &= ~((u64)sectorsize - 1);
2656         /* backup for extent #0 should exist */
2657         if(!test_range_bit(&io_tree, 0, first_free - 1, EXTENT_LOCKED, 1)) {
2658                 fprintf(stderr, "no backup for the first extent\n");
2659                 goto fail;
2660         }
2661         /* force no allocation from system block group */
2662         root->fs_info->system_allocs = -1;
2663         trans = btrfs_start_transaction(root, 1);
2664         BUG_ON(!trans);
2665         /*
2666          * recow the whole chunk tree, this will remove all chunk tree blocks
2667          * from system block group
2668          */
2669         chunk_root = root->fs_info->chunk_root;
2670         memset(&key, 0, sizeof(key));
2671         while (1) {
2672                 ret = btrfs_search_slot(trans, chunk_root, &key, &path, 0, 1);
2673                 if (ret < 0)
2674                         break;
2675
2676                 ret = btrfs_next_leaf(chunk_root, &path);
2677                 if (ret)
2678                         break;
2679
2680                 btrfs_item_key_to_cpu(path.nodes[0], &key, path.slots[0]);
2681                 btrfs_release_path(&path);
2682         }
2683         btrfs_release_path(&path);
2684
2685         offset = 0;
2686         num_bytes = 0;
2687         while(1) {
2688                 cache1 = btrfs_lookup_block_group(root->fs_info, offset);
2689                 if (!cache1)
2690                         break;
2691
2692                 if (cache1->flags & BTRFS_BLOCK_GROUP_SYSTEM)
2693                         num_bytes += btrfs_block_group_used(&cache1->item);
2694
2695                 offset = cache1->key.objectid + cache1->key.offset;
2696         }
2697         /* only extent #0 left in system block group? */
2698         if (num_bytes > first_free) {
2699                 fprintf(stderr, "unable to empty system block group\n");
2700                 goto fail;
2701         }
2702         /* create a system chunk that maps the whole device */
2703         ret = prepare_system_chunk_sb(root->fs_info->super_copy);
2704         if (ret) {
2705                 fprintf(stderr, "unable to update system chunk\n");
2706                 goto fail;
2707         }
2708
2709         ret = btrfs_commit_transaction(trans, root);
2710         BUG_ON(ret);
2711
2712         ret = close_ctree(root);
2713         if (ret) {
2714                 fprintf(stderr, "error during close_ctree %d\n", ret);
2715                 goto fail;
2716         }
2717
2718         /* zero btrfs super block mirrors */
2719         memset(buf, 0, sectorsize);
2720         for (i = 1 ; i < BTRFS_SUPER_MIRROR_MAX; i++) {
2721                 bytenr = btrfs_sb_offset(i);
2722                 if (bytenr >= total_bytes)
2723                         break;
2724                 ret = pwrite(fd, buf, sectorsize, bytenr);
2725                 if (ret != sectorsize) {
2726                         fprintf(stderr,
2727                                 "error during zeroing supreblock %d: %d\n",
2728                                 i, ret);
2729                         goto fail;
2730                 }
2731         }
2732
2733         sb_bytenr = (u64)-1;
2734         /* copy all relocated blocks back */
2735         while(1) {
2736                 ret = find_first_extent_bit(&io_tree, 0, &start, &end,
2737                                             EXTENT_LOCKED);
2738                 if (ret)
2739                         break;
2740
2741                 ret = get_state_private(&io_tree, start, &bytenr);
2742                 BUG_ON(ret);
2743
2744                 clear_extent_bits(&io_tree, start, end, EXTENT_LOCKED,
2745                                   GFP_NOFS);
2746
2747                 while (start <= end) {
2748                         if (start == BTRFS_SUPER_INFO_OFFSET) {
2749                                 sb_bytenr = bytenr;
2750                                 goto next_sector;
2751                         }
2752                         ret = pread(fd, buf, sectorsize, bytenr);
2753                         if (ret < 0) {
2754                                 fprintf(stderr, "error during pread %d\n", ret);
2755                                 goto fail;
2756                         }
2757                         BUG_ON(ret != sectorsize);
2758                         ret = pwrite(fd, buf, sectorsize, start);
2759                         if (ret < 0) {
2760                                 fprintf(stderr, "error during pwrite %d\n", ret);
2761                                 goto fail;
2762                         }
2763                         BUG_ON(ret != sectorsize);
2764 next_sector:
2765                         start += sectorsize;
2766                         bytenr += sectorsize;
2767                 }
2768         }
2769
2770         ret = fsync(fd);
2771         if (ret) {
2772                 fprintf(stderr, "error during fsync %d\n", ret);
2773                 goto fail;
2774         }
2775         /*
2776          * finally, overwrite btrfs super block.
2777          */
2778         ret = pread(fd, buf, sectorsize, sb_bytenr);
2779         if (ret < 0) {
2780                 fprintf(stderr, "error during pread %d\n", ret);
2781                 goto fail;
2782         }
2783         BUG_ON(ret != sectorsize);
2784         ret = pwrite(fd, buf, sectorsize, BTRFS_SUPER_INFO_OFFSET);
2785         if (ret < 0) {
2786                 fprintf(stderr, "error during pwrite %d\n", ret);
2787                 goto fail;
2788         }
2789         BUG_ON(ret != sectorsize);
2790         ret = fsync(fd);
2791         if (ret) {
2792                 fprintf(stderr, "error during fsync %d\n", ret);
2793                 goto fail;
2794         }
2795
2796         close(fd);
2797         free(buf);
2798         extent_io_tree_cleanup(&io_tree);
2799         printf("rollback complete.\n");
2800         return 0;
2801
2802 fail:
2803         if (fd != -1)
2804                 close(fd);
2805         free(buf);
2806         fprintf(stderr, "rollback aborted.\n");
2807         return -1;
2808 }
2809
2810 static void print_usage(void)
2811 {
2812         printf("usage: btrfs-convert [options] device\n");
2813         printf("options:\n");
2814         printf("\t-d|--no-datasum        disable data checksum, sets NODATASUM\n");
2815         printf("\t-i|--no-xattr          ignore xattrs and ACLs\n");
2816         printf("\t-n|--no-inline         disable inlining of small files to metadata\n");
2817         printf("\t-N|--nodesize SIZE     set filesystem metadata nodesize\n");
2818         printf("\t-r|--rollback          roll back to ext2fs\n");
2819         printf("\t-l|--label LABEL       set filesystem label\n");
2820         printf("\t-L|--copy-label        use label from converted filesystem\n");
2821         printf("\t-p|--progress          show converting progress (default)\n");
2822         printf("\t--no-progress          show only overview, not the detailed progress\n");
2823 }
2824
2825 int main(int argc, char *argv[])
2826 {
2827         int ret;
2828         int packing = 1;
2829         int noxattr = 0;
2830         int datacsum = 1;
2831         u32 nodesize = max_t(u32, sysconf(_SC_PAGESIZE),
2832                         BTRFS_MKFS_DEFAULT_NODE_SIZE);
2833         int rollback = 0;
2834         int copylabel = 0;
2835         int usage_error = 0;
2836         int progress = 1;
2837         char *file;
2838         char *fslabel = NULL;
2839
2840         while(1) {
2841                 enum { GETOPT_VAL_NO_PROGRESS = 256 };
2842                 static const struct option long_options[] = {
2843                         { "no-progress", no_argument, NULL,
2844                                 GETOPT_VAL_NO_PROGRESS },
2845                         { "no-datasum", no_argument, NULL, 'd' },
2846                         { "no-inline", no_argument, NULL, 'n' },
2847                         { "no-xattr", no_argument, NULL, 'i' },
2848                         { "rollback", no_argument, NULL, 'r' },
2849                         { "progress", no_argument, NULL, 'p' },
2850                         { "label", required_argument, NULL, 'l' },
2851                         { "copy-label", no_argument, NULL, 'L' },
2852                         { "nodesize", required_argument, NULL, 'N' },
2853                         { NULL, 0, NULL, 0 }
2854                 };
2855                 int c = getopt_long(argc, argv, "dinN:rl:Lp", long_options, NULL);
2856
2857                 if (c < 0)
2858                         break;
2859                 switch(c) {
2860                         case 'd':
2861                                 datacsum = 0;
2862                                 break;
2863                         case 'i':
2864                                 noxattr = 1;
2865                                 break;
2866                         case 'n':
2867                                 packing = 0;
2868                                 break;
2869                         case 'N':
2870                                 nodesize = parse_size(optarg);
2871                                 break;
2872                         case 'r':
2873                                 rollback = 1;
2874                                 break;
2875                         case 'l':
2876                                 copylabel = -1;
2877                                 fslabel = strdup(optarg);
2878                                 if (strlen(fslabel) > BTRFS_LABEL_SIZE) {
2879                                         fprintf(stderr,
2880                                                 "warning: label too long, trimmed to %d bytes\n",
2881                                                 BTRFS_LABEL_SIZE);
2882                                         fslabel[BTRFS_LABEL_SIZE] = 0;
2883                                 }
2884                                 break;
2885                         case 'L':
2886                                 copylabel = 1;
2887                                 break;
2888                         case 'p':
2889                                 progress = 1;
2890                                 break;
2891                         case GETOPT_VAL_NO_PROGRESS:
2892                                 progress = 0;
2893                                 break;
2894                         default:
2895                                 print_usage();
2896                                 return 1;
2897                 }
2898         }
2899         argc = argc - optind;
2900         set_argv0(argv);
2901         if (check_argc_exact(argc, 1)) {
2902                 print_usage();
2903                 return 1;
2904         }
2905
2906         if (rollback && (!datacsum || noxattr || !packing)) {
2907                 fprintf(stderr,
2908                         "Usage error: -d, -i, -n options do not apply to rollback\n");
2909                 usage_error++;
2910         }
2911
2912         if (usage_error) {
2913                 print_usage();
2914                 return 1;
2915         }
2916
2917         file = argv[optind];
2918         ret = check_mounted(file);
2919         if (ret < 0) {
2920                 fprintf(stderr, "Could not check mount status: %s\n",
2921                         strerror(-ret));
2922                 return 1;
2923         } else if (ret) {
2924                 fprintf(stderr, "%s is mounted\n", file);
2925                 return 1;
2926         }
2927
2928         if (rollback) {
2929                 ret = do_rollback(file);
2930         } else {
2931                 ret = do_convert(file, datacsum, packing, noxattr, nodesize,
2932                                 copylabel, fslabel, progress);
2933         }
2934         if (ret)
2935                 return 1;
2936         return 0;
2937 }