/* * Copyright (C) 2007 Oracle. All rights reserved. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public * License v2 as published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public * License along with this program; if not, write to the * Free Software Foundation, Inc., 59 Temple Place - Suite 330, * Boston, MA 021110-1307, USA. */ /* * Btrfs convert design: * * The overall design of btrfs convert is like the following: * * |<------------------Old fs----------------------------->| * |<- used ->| |<- used ->| |<- used ->| * || * \/ * |<---------------Btrfs fs------------------------------>| * |<- Old data chunk ->|< new chunk (D/M/S)>|<- ODC ->| * |<-Old-FE->| |<-Old-FE->|<- Btrfs extents ->|<-Old-FE->| * * ODC = Old data chunk, btrfs chunks containing old fs data * Mapped 1:1 (logical address == device offset) * Old-FE = file extents pointing to old fs. * * So old fs used space is (mostly) kept as is, while btrfs will insert * its chunk (Data/Meta/Sys) into large enough free space. * In this way, we can create different profiles for metadata/data for * converted fs. * * We must reserve and relocate 3 ranges for btrfs: * * [0, 1M) - area never used for any data except the first * superblock * * [btrfs_sb_offset(1), +64K) - 1st superblock backup copy * * [btrfs_sb_offset(2), +64K) - 2nd, dtto * * Most work is spent handling corner cases around these reserved ranges. * * Detailed workflow is: * 1) Scan old fs used space and calculate data chunk layout * 1.1) Scan old fs * We can a map used space of old fs * * 1.2) Calculate data chunk layout - this is the hard part * New data chunks must meet 3 conditions using result from 1.1 * a. Large enough to be a chunk * b. Doesn't intersect reserved ranges * c. Covers all the remaining old fs used space * * NOTE: This can be simplified if we don't need to handle backup supers * * 1.3) Calculate usable space for new btrfs chunks * Btrfs chunk usable space must meet 3 conditions using result from 1.2 * a. Large enough to be a chunk * b. Doesn't intersect reserved ranges * c. Doesn't cover any data chunks in 1.1 * * 2) Create basic btrfs filesystem structure * Initial metadata and sys chunks are inserted in the first available * space found in step 1.3 * Then insert all data chunks into the basic btrfs * * 3) Create convert image * We need to relocate reserved ranges here. * After this step, the convert image is done, and we can use the image * as reflink source to create old files * * 4) Iterate old fs to create files * We just reflink file extents from old fs to newly created files on * btrfs. */ #include "kerncompat.h" #include #include #include #include #include #include #include #include #include #include "kernel-shared/ctree.h" #include "kernel-shared/disk-io.h" #include "kernel-shared/volumes.h" #include "kernel-shared/transaction.h" #include "common/utils.h" #include "common/task-utils.h" #include "common/path-utils.h" #include "common/help.h" #include "common/parse-utils.h" #include "mkfs/common.h" #include "convert/common.h" #include "convert/source-fs.h" #include "crypto/crc32c.h" #include "common/fsfeatures.h" #include "common/device-scan.h" #include "common/box.h" #include "common/open-utils.h" #include "common/repair.h" extern const struct btrfs_convert_operations ext2_convert_ops; extern const struct btrfs_convert_operations reiserfs_convert_ops; static const struct btrfs_convert_operations *convert_operations[] = { #if BTRFSCONVERT_EXT2 &ext2_convert_ops, #endif #if BTRFSCONVERT_REISERFS &reiserfs_convert_ops, #endif }; static void *print_copied_inodes(void *p) { struct task_ctx *priv = p; const char work_indicator[] = { '.', 'o', 'O', 'o' }; u64 count = 0; task_period_start(priv->info, 1000 /* 1s */); while (1) { count++; pthread_mutex_lock(&priv->mutex); printf("Copy inodes [%c] [%10llu/%10llu]\r", work_indicator[count % 4], (unsigned long long)priv->cur_copy_inodes, (unsigned long long)priv->max_copy_inodes); pthread_mutex_unlock(&priv->mutex); fflush(stdout); task_period_wait(priv->info); } return NULL; } static int after_copied_inodes(void *p) { printf("\n"); fflush(stdout); return 0; } static inline int copy_inodes(struct btrfs_convert_context *cctx, struct btrfs_root *root, u32 convert_flags, struct task_ctx *p) { return cctx->convert_ops->copy_inodes(cctx, root, convert_flags, p); } static inline void convert_close_fs(struct btrfs_convert_context *cctx) { cctx->convert_ops->close_fs(cctx); } static inline int convert_check_state(struct btrfs_convert_context *cctx) { return cctx->convert_ops->check_state(cctx); } static int csum_disk_extent(struct btrfs_trans_handle *trans, struct btrfs_root *root, u64 disk_bytenr, u64 num_bytes) { u32 blocksize = root->fs_info->sectorsize; u64 offset; char *buffer; int ret = 0; buffer = malloc(blocksize); if (!buffer) return -ENOMEM; for (offset = 0; offset < num_bytes; offset += blocksize) { ret = read_disk_extent(root, disk_bytenr + offset, blocksize, buffer); if (ret) break; ret = btrfs_csum_file_block(trans, disk_bytenr + num_bytes, disk_bytenr + offset, buffer, blocksize); if (ret) break; } free(buffer); return ret; } static int create_image_file_range(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct cache_tree *used, struct btrfs_inode_item *inode, u64 ino, u64 bytenr, u64 *ret_len, u32 convert_flags) { struct cache_extent *cache; struct btrfs_block_group *bg_cache; u64 len = *ret_len; u64 disk_bytenr; int i; int ret; u32 datacsum = convert_flags & CONVERT_FLAG_DATACSUM; if (bytenr != round_down(bytenr, root->fs_info->sectorsize)) { error("bytenr not sectorsize aligned: %llu", (unsigned long long)bytenr); return -EINVAL; } if (len != round_down(len, root->fs_info->sectorsize)) { error("length not sectorsize aligned: %llu", (unsigned long long)len); return -EINVAL; } len = min_t(u64, len, BTRFS_MAX_EXTENT_SIZE); /* * Skip reserved ranges first * * Or we will insert a hole into current image file, and later * migrate block will fail as there is already a file extent. */ for (i = 0; i < ARRAY_SIZE(btrfs_reserved_ranges); i++) { const struct simple_range *reserved = &btrfs_reserved_ranges[i]; /* * |-- reserved --| * |--range---| * or * |---- reserved ----| * |-- range --| * Skip to reserved range end */ if (bytenr >= reserved->start && bytenr < range_end(reserved)) { *ret_len = range_end(reserved) - bytenr; return 0; } /* * |---reserved---| * |----range-------| * Leading part may still create a file extent */ if (bytenr < reserved->start && bytenr + len >= range_end(reserved)) { len = min_t(u64, len, reserved->start - bytenr); break; } } /* Check if we are going to insert regular file extent, or hole */ cache = search_cache_extent(used, bytenr); if (cache) { if (cache->start <= bytenr) { /* * |///////Used///////| * |<--insert--->| * bytenr * Insert one real file extent */ len = min_t(u64, len, cache->start + cache->size - bytenr); disk_bytenr = bytenr; } else { /* * |//Used//| * |<-insert-->| * bytenr * Insert one hole */ len = min(len, cache->start - bytenr); disk_bytenr = 0; datacsum = 0; } } else { /* * |//Used//| |EOF * |<-insert-->| * bytenr * Insert one hole */ disk_bytenr = 0; datacsum = 0; } if (disk_bytenr) { /* Check if the range is in a data block group */ bg_cache = btrfs_lookup_block_group(root->fs_info, bytenr); if (!bg_cache) { error("missing data block for bytenr %llu", bytenr); return -ENOENT; } if (!(bg_cache->flags & BTRFS_BLOCK_GROUP_DATA)) { error( "data bytenr %llu is covered by non-data block group %llu flags 0x%llu", bytenr, bg_cache->start, bg_cache->flags); return -EINVAL; } /* The extent should never cross block group boundary */ len = min_t(u64, len, bg_cache->start + bg_cache->length - bytenr); } if (len != round_down(len, root->fs_info->sectorsize)) { error("remaining length not sectorsize aligned: %llu", (unsigned long long)len); return -EINVAL; } ret = btrfs_record_file_extent(trans, root, ino, inode, bytenr, disk_bytenr, len); if (ret < 0) return ret; if (datacsum) { ret = csum_disk_extent(trans, root, bytenr, len); if (ret < 0) { errno = -ret; error( "failed to calculate csum for bytenr %llu len %llu: %m", bytenr, len); } } *ret_len = len; return ret; } /* * Relocate old fs data in one reserved ranges * * Since all old fs data in reserved range is not covered by any chunk nor * data extent, we don't need to handle any reference but add new * extent/reference, which makes codes more clear */ static int migrate_one_reserved_range(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct cache_tree *used, struct btrfs_inode_item *inode, int fd, u64 ino, const struct simple_range *range, u32 convert_flags) { u64 cur_off = range->start; u64 cur_len = range->len; u64 hole_start = range->start; u64 hole_len; struct cache_extent *cache; struct btrfs_key key; struct extent_buffer *eb; int ret = 0; /* * It's possible that there are holes in reserved range: * |<---------------- Reserved range ---------------------->| * |<- Old fs data ->| |<- Old fs data ->| * So here we need to iterate through old fs used space and only * migrate ranges that covered by old fs data. */ while (cur_off < range_end(range)) { cache = search_cache_extent(used, cur_off); if (!cache) break; cur_off = max(cache->start, cur_off); if (cur_off >= range_end(range)) break; cur_len = min(cache->start + cache->size, range_end(range)) - cur_off; BUG_ON(cur_len < root->fs_info->sectorsize); /* reserve extent for the data */ ret = btrfs_reserve_extent(trans, root, cur_len, 0, 0, (u64)-1, &key, 1); if (ret < 0) break; eb = malloc(sizeof(*eb) + cur_len); if (!eb) { ret = -ENOMEM; break; } ret = pread(fd, eb->data, cur_len, cur_off); if (ret < cur_len) { ret = (ret < 0 ? ret : -EIO); free(eb); break; } eb->start = key.objectid; eb->len = key.offset; eb->fs_info = root->fs_info; /* Write the data */ ret = write_and_map_eb(root->fs_info, eb); free(eb); if (ret < 0) break; /* Now handle extent item and file extent things */ ret = btrfs_record_file_extent(trans, root, ino, inode, cur_off, key.objectid, key.offset); if (ret < 0) break; /* Finally, insert csum items */ if (convert_flags & CONVERT_FLAG_DATACSUM) ret = csum_disk_extent(trans, root, key.objectid, key.offset); /* Don't forget to insert hole */ hole_len = cur_off - hole_start; if (hole_len) { ret = btrfs_record_file_extent(trans, root, ino, inode, hole_start, 0, hole_len); if (ret < 0) break; } cur_off += key.offset; hole_start = cur_off; cur_len = range_end(range) - cur_off; } /* * Last hole * |<---- reserved -------->| * |<- Old fs data ->| | * | Hole | */ if (range_end(range) - hole_start > 0) ret = btrfs_record_file_extent(trans, root, ino, inode, hole_start, 0, range_end(range) - hole_start); return ret; } /* * Relocate the used source fs data in reserved ranges */ static int migrate_reserved_ranges(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct cache_tree *used, struct btrfs_inode_item *inode, int fd, u64 ino, u64 total_bytes, u32 convert_flags) { int i; int ret = 0; for (i = 0; i < ARRAY_SIZE(btrfs_reserved_ranges); i++) { const struct simple_range *range = &btrfs_reserved_ranges[i]; if (range->start > total_bytes) return ret; ret = migrate_one_reserved_range(trans, root, used, inode, fd, ino, range, convert_flags); if (ret < 0) return ret; } return ret; } /* * Helper for expand and merge extent_cache for wipe_one_reserved_range() to * handle wiping a range that exists in cache. */ static int _expand_extent_cache(struct cache_tree *tree, struct cache_extent *entry, u64 min_stripe_size, int backward) { struct cache_extent *ce; int diff; if (entry->size >= min_stripe_size) return 0; diff = min_stripe_size - entry->size; if (backward) { ce = prev_cache_extent(entry); if (!ce) goto expand_back; if (ce->start + ce->size >= entry->start - diff) { /* Directly merge with previous extent */ ce->size = entry->start + entry->size - ce->start; remove_cache_extent(tree, entry); free(entry); return 0; } expand_back: /* No overlap, normal extent */ if (entry->start < diff) { error("cannot find space for data chunk layout"); return -ENOSPC; } entry->start -= diff; entry->size += diff; return 0; } ce = next_cache_extent(entry); if (!ce) goto expand_after; if (entry->start + entry->size + diff >= ce->start) { /* Directly merge with next extent */ entry->size = ce->start + ce->size - entry->start; remove_cache_extent(tree, ce); free(ce); return 0; } expand_after: entry->size += diff; return 0; } /* * Remove one reserve range from given cache tree * if min_stripe_size is non-zero, it will ensure for split case, * all its split cache extent is no smaller than @min_strip_size / 2. */ static int wipe_one_reserved_range(struct cache_tree *tree, u64 start, u64 len, u64 min_stripe_size, int ensure_size) { struct cache_extent *cache; int ret; BUG_ON(ensure_size && min_stripe_size == 0); /* * The logical here is simplified to handle special cases only * So we don't need to consider merge case for ensure_size */ BUG_ON(min_stripe_size && (min_stripe_size < len * 2 || min_stripe_size / 2 < BTRFS_STRIPE_LEN)); /* Also, wipe range should already be aligned */ BUG_ON(start != round_down(start, BTRFS_STRIPE_LEN) || start + len != round_up(start + len, BTRFS_STRIPE_LEN)); min_stripe_size /= 2; cache = lookup_cache_extent(tree, start, len); if (!cache) return 0; if (start <= cache->start) { /* * |--------cache---------| * |-wipe-| */ BUG_ON(start + len <= cache->start); /* * The wipe size is smaller than min_stripe_size / 2, * so the result length should still meet min_stripe_size * And no need to do alignment */ cache->size -= (start + len - cache->start); if (cache->size == 0) { remove_cache_extent(tree, cache); free(cache); return 0; } BUG_ON(ensure_size && cache->size < min_stripe_size); cache->start = start + len; return 0; } else if (start > cache->start && start + len < cache->start + cache->size) { /* * |-------cache-----| * |-wipe-| */ u64 old_start = cache->start; u64 old_len = cache->size; u64 insert_start = start + len; u64 insert_len; cache->size = start - cache->start; /* Expand the leading half part if needed */ if (ensure_size && cache->size < min_stripe_size) { ret = _expand_extent_cache(tree, cache, min_stripe_size, 1); if (ret < 0) return ret; } /* And insert the new one */ insert_len = old_start + old_len - start - len; ret = add_merge_cache_extent(tree, insert_start, insert_len); if (ret < 0) return ret; /* Expand the last half part if needed */ if (ensure_size && insert_len < min_stripe_size) { cache = lookup_cache_extent(tree, insert_start, insert_len); if (!cache || cache->start != insert_start || cache->size != insert_len) return -ENOENT; ret = _expand_extent_cache(tree, cache, min_stripe_size, 0); } return ret; } /* * |----cache-----| * |--wipe-| * Wipe len should be small enough and no need to expand the * remaining extent */ cache->size = start - cache->start; BUG_ON(ensure_size && cache->size < min_stripe_size); return 0; } /* * Remove reserved ranges from given cache_tree * * It will remove the following ranges * 1) 0~1M * 2) 2nd superblock, +64K (make sure chunks are 64K aligned) * 3) 3rd superblock, +64K * * @min_stripe must be given for safety check * and if @ensure_size is given, it will ensure affected cache_extent will be * larger than min_stripe_size */ static int wipe_reserved_ranges(struct cache_tree *tree, u64 min_stripe_size, int ensure_size) { int i; int ret; for (i = 0; i < ARRAY_SIZE(btrfs_reserved_ranges); i++) { const struct simple_range *range = &btrfs_reserved_ranges[i]; ret = wipe_one_reserved_range(tree, range->start, range->len, min_stripe_size, ensure_size); if (ret < 0) return ret; } return ret; } static int calculate_available_space(struct btrfs_convert_context *cctx) { struct cache_tree *used = &cctx->used_space; struct cache_tree *data_chunks = &cctx->data_chunks; struct cache_tree *free = &cctx->free_space; struct cache_extent *cache; u64 cur_off = 0; /* * Twice the minimal chunk size, to allow later wipe_reserved_ranges() * works without need to consider overlap */ u64 min_stripe_size = SZ_32M; int ret; /* Calculate data_chunks */ for (cache = first_cache_extent(used); cache; cache = next_cache_extent(cache)) { u64 cur_len; if (cache->start + cache->size < cur_off) continue; if (cache->start > cur_off + min_stripe_size) cur_off = cache->start; cur_len = max(cache->start + cache->size - cur_off, min_stripe_size); /* data chunks should never exceed device boundary */ cur_len = min(cctx->total_bytes - cur_off, cur_len); ret = add_merge_cache_extent(data_chunks, cur_off, cur_len); if (ret < 0) goto out; cur_off += cur_len; } /* * remove reserved ranges, so we won't ever bother relocating an old * filesystem extent to other place. */ ret = wipe_reserved_ranges(data_chunks, min_stripe_size, 1); if (ret < 0) goto out; cur_off = 0; /* * Calculate free space * Always round up the start bytenr, to avoid metadata extent cross * stripe boundary, as later mkfs_convert() won't have all the extent * allocation check */ for (cache = first_cache_extent(data_chunks); cache; cache = next_cache_extent(cache)) { if (cache->start < cur_off) continue; if (cache->start > cur_off) { u64 insert_start; u64 len; len = cache->start - round_up(cur_off, BTRFS_STRIPE_LEN); insert_start = round_up(cur_off, BTRFS_STRIPE_LEN); ret = add_merge_cache_extent(free, insert_start, len); if (ret < 0) goto out; } cur_off = cache->start + cache->size; } /* Don't forget the last range */ if (cctx->total_bytes > cur_off) { u64 len = cctx->total_bytes - cur_off; u64 insert_start; insert_start = round_up(cur_off, BTRFS_STRIPE_LEN); ret = add_merge_cache_extent(free, insert_start, len); if (ret < 0) goto out; } /* Remove reserved bytes */ ret = wipe_reserved_ranges(free, min_stripe_size, 0); out: return ret; } static int copy_free_space_tree(struct btrfs_convert_context *cctx) { struct cache_tree *src = &cctx->free_space; struct cache_tree *dst = &cctx->free_space_initial; struct cache_extent *cache; int ret = 0; for (cache = search_cache_extent(src, 0); cache; cache = next_cache_extent(cache)) { ret = add_merge_cache_extent(dst, cache->start, cache->size); if (ret < 0) return ret; cctx->free_bytes_initial += cache->size; } return ret; } /* * Read used space, and since we have the used space, * calculate data_chunks and free for later mkfs */ static int convert_read_used_space(struct btrfs_convert_context *cctx) { int ret; ret = cctx->convert_ops->read_used_space(cctx); if (ret) return ret; ret = calculate_available_space(cctx); if (ret < 0) return ret; return copy_free_space_tree(cctx); } /* * Create the fs image file of old filesystem. * * This is completely fs independent as we have cctx->used, only * need to create file extents pointing to all the positions. */ static int create_image(struct btrfs_root *root, struct btrfs_mkfs_config *cfg, struct btrfs_convert_context *cctx, int fd, u64 size, char *name, u32 convert_flags) { struct btrfs_inode_item buf; struct btrfs_trans_handle *trans; struct btrfs_path path; struct btrfs_key key; struct cache_extent *cache; struct cache_tree used_tmp; u64 cur; u64 ino; u64 flags = BTRFS_INODE_READONLY; int ret; if (!(convert_flags & CONVERT_FLAG_DATACSUM)) flags |= BTRFS_INODE_NODATASUM; trans = btrfs_start_transaction(root, 1); if (IS_ERR(trans)) return PTR_ERR(trans); cache_tree_init(&used_tmp); btrfs_init_path(&path); ret = btrfs_find_free_objectid(trans, root, BTRFS_FIRST_FREE_OBJECTID, &ino); if (ret < 0) { errno = -ret; error("failed to find free objectid for root %llu: %m", root->root_key.objectid); goto out; } ret = btrfs_new_inode(trans, root, ino, 0400 | S_IFREG); if (ret < 0) { errno = -ret; error("failed to create new inode for root %llu: %m", root->root_key.objectid); goto out; } ret = btrfs_change_inode_flags(trans, root, ino, flags); if (ret < 0) { errno = -ret; error("failed to change inode flag for ino %llu root %llu: %m", ino, root->root_key.objectid); goto out; } ret = btrfs_add_link(trans, root, ino, BTRFS_FIRST_FREE_OBJECTID, name, strlen(name), BTRFS_FT_REG_FILE, NULL, 1, 0); if (ret < 0) { errno = -ret; error("failed to link ino %llu to '/%s' in root %llu: %m", ino, name, root->root_key.objectid); goto out; } key.objectid = ino; key.type = BTRFS_INODE_ITEM_KEY; key.offset = 0; ret = btrfs_search_slot(trans, root, &key, &path, 0, 1); if (ret) { ret = (ret > 0 ? -ENOENT : ret); goto out; } read_extent_buffer(path.nodes[0], &buf, btrfs_item_ptr_offset(path.nodes[0], path.slots[0]), sizeof(buf)); btrfs_release_path(&path); /* * Create a new used space cache, which doesn't contain the reserved * range */ for (cache = first_cache_extent(&cctx->used_space); cache; cache = next_cache_extent(cache)) { ret = add_cache_extent(&used_tmp, cache->start, cache->size); if (ret < 0) goto out; } ret = wipe_reserved_ranges(&used_tmp, 0, 0); if (ret < 0) goto out; /* * Start from 1M, as 0~1M is reserved, and create_image_file_range() * can't handle bytenr 0(will consider it as a hole) */ cur = SZ_1M; while (cur < size) { u64 len = size - cur; ret = create_image_file_range(trans, root, &used_tmp, &buf, ino, cur, &len, convert_flags); if (ret < 0) goto out; cur += len; } /* Handle the reserved ranges */ ret = migrate_reserved_ranges(trans, root, &cctx->used_space, &buf, fd, ino, cfg->num_bytes, convert_flags); key.objectid = ino; key.type = BTRFS_INODE_ITEM_KEY; key.offset = 0; ret = btrfs_search_slot(trans, root, &key, &path, 0, 1); if (ret) { ret = (ret > 0 ? -ENOENT : ret); goto out; } btrfs_set_stack_inode_size(&buf, cfg->num_bytes); write_extent_buffer(path.nodes[0], &buf, btrfs_item_ptr_offset(path.nodes[0], path.slots[0]), sizeof(buf)); out: free_extent_cache_tree(&used_tmp); btrfs_release_path(&path); btrfs_commit_transaction(trans, root); return ret; } static int create_subvol(struct btrfs_trans_handle *trans, struct btrfs_root *root, u64 root_objectid) { struct extent_buffer *tmp; struct btrfs_root *new_root; struct btrfs_key key; struct btrfs_root_item root_item; int ret; ret = btrfs_copy_root(trans, root, root->node, &tmp, root_objectid); if (ret) return ret; memcpy(&root_item, &root->root_item, sizeof(root_item)); btrfs_set_root_bytenr(&root_item, tmp->start); btrfs_set_root_level(&root_item, btrfs_header_level(tmp)); btrfs_set_root_generation(&root_item, trans->transid); free_extent_buffer(tmp); key.objectid = root_objectid; key.type = BTRFS_ROOT_ITEM_KEY; key.offset = trans->transid; ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key, &root_item); key.offset = (u64)-1; new_root = btrfs_read_fs_root(root->fs_info, &key); if (!new_root || IS_ERR(new_root)) { error("unable to fs read root: %lu", PTR_ERR(new_root)); return PTR_ERR(new_root); } ret = btrfs_make_root_dir(trans, new_root, BTRFS_FIRST_FREE_OBJECTID); return ret; } /* * New make_btrfs() has handle system and meta chunks quite well. * So only need to add remaining data chunks. */ static int make_convert_data_block_groups(struct btrfs_trans_handle *trans, struct btrfs_fs_info *fs_info, struct btrfs_mkfs_config *cfg, struct btrfs_convert_context *cctx) { struct cache_tree *data_chunks = &cctx->data_chunks; struct cache_extent *cache; u64 max_chunk_size; int ret = 0; /* * Don't create data chunk over 10% of the convert device * And for single chunk, don't create chunk larger than 1G. */ max_chunk_size = cfg->num_bytes / 10; max_chunk_size = min((u64)(SZ_1G), max_chunk_size); max_chunk_size = round_down(max_chunk_size, fs_info->sectorsize); for (cache = first_cache_extent(data_chunks); cache; cache = next_cache_extent(cache)) { u64 cur = cache->start; while (cur < cache->start + cache->size) { u64 len; u64 cur_backup = cur; len = min(max_chunk_size, cache->start + cache->size - cur); ret = btrfs_alloc_data_chunk(trans, fs_info, &cur_backup, len); if (ret < 0) break; ret = btrfs_make_block_group(trans, fs_info, 0, BTRFS_BLOCK_GROUP_DATA, cur, len); if (ret < 0) break; cur += len; } } return ret; } /* * Init the temp btrfs to a operational status. * * It will fix the extent usage accounting(XXX: Do we really need?) and * insert needed data chunks, to ensure all old fs data extents are covered * by DATA chunks, preventing wrong chunks are allocated. * * And also create convert image subvolume and relocation tree. * (XXX: Not need again?) * But the convert image subvolume is *NOT* linked to fs tree yet. */ static int init_btrfs(struct btrfs_mkfs_config *cfg, struct btrfs_root *root, struct btrfs_convert_context *cctx, u32 convert_flags) { struct btrfs_key location; struct btrfs_trans_handle *trans; struct btrfs_fs_info *fs_info = root->fs_info; int ret; /* * Don't alloc any metadata/system chunk, as we don't want * any meta/sys chunk allocated before all data chunks are inserted. * Or we screw up the chunk layout just like the old implement. */ fs_info->avoid_sys_chunk_alloc = 1; fs_info->avoid_meta_chunk_alloc = 1; trans = btrfs_start_transaction(root, 1); if (IS_ERR(trans)) { error("unable to start transaction"); ret = PTR_ERR(trans); goto err; } ret = btrfs_fix_block_accounting(trans); if (ret) goto err; ret = make_convert_data_block_groups(trans, fs_info, cfg, cctx); if (ret) goto err; ret = btrfs_make_root_dir(trans, fs_info->tree_root, BTRFS_ROOT_TREE_DIR_OBJECTID); if (ret) goto err; memcpy(&location, &root->root_key, sizeof(location)); location.offset = (u64)-1; ret = btrfs_insert_dir_item(trans, fs_info->tree_root, "default", 7, btrfs_super_root_dir(fs_info->super_copy), &location, BTRFS_FT_DIR, 0); if (ret) goto err; ret = btrfs_insert_inode_ref(trans, fs_info->tree_root, "default", 7, location.objectid, btrfs_super_root_dir(fs_info->super_copy), 0); if (ret) goto err; btrfs_set_root_dirid(&fs_info->fs_root->root_item, BTRFS_FIRST_FREE_OBJECTID); /* subvol for fs image file */ ret = create_subvol(trans, root, CONV_IMAGE_SUBVOL_OBJECTID); if (ret < 0) { error("failed to create subvolume image root: %d", ret); goto err; } /* subvol for data relocation tree */ ret = create_subvol(trans, root, BTRFS_DATA_RELOC_TREE_OBJECTID); if (ret < 0) { error("failed to create DATA_RELOC root: %d", ret); goto err; } ret = btrfs_commit_transaction(trans, root); fs_info->avoid_sys_chunk_alloc = 0; fs_info->avoid_meta_chunk_alloc = 0; err: return ret; } /* * Migrate super block to its default position and zero 0 ~ 16k */ static int migrate_super_block(int fd, u64 old_bytenr) { int ret; struct btrfs_super_block super; u8 result[BTRFS_CSUM_SIZE] = {}; u32 len; u32 bytenr; ret = pread(fd, &super, BTRFS_SUPER_INFO_SIZE, old_bytenr); if (ret != BTRFS_SUPER_INFO_SIZE) goto fail; BUG_ON(btrfs_super_bytenr(&super) != old_bytenr); btrfs_set_super_bytenr(&super, BTRFS_SUPER_INFO_OFFSET); btrfs_csum_data(NULL, btrfs_super_csum_type(&super), (u8 *)&super + BTRFS_CSUM_SIZE, result, BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE); memcpy(&super.csum[0], result, BTRFS_CSUM_SIZE); ret = pwrite(fd, &super , BTRFS_SUPER_INFO_SIZE, BTRFS_SUPER_INFO_OFFSET); if (ret != BTRFS_SUPER_INFO_SIZE) goto fail; ret = fsync(fd); if (ret) goto fail; memset(&super, 0, BTRFS_SUPER_INFO_SIZE); for (bytenr = 0; bytenr < BTRFS_SUPER_INFO_OFFSET; ) { len = BTRFS_SUPER_INFO_OFFSET - bytenr; if (len > BTRFS_SUPER_INFO_SIZE) len = BTRFS_SUPER_INFO_SIZE; ret = pwrite(fd, &super, len, bytenr); if (ret != len) { fprintf(stderr, "unable to zero fill device\n"); break; } bytenr += len; } ret = 0; fsync(fd); fail: if (ret > 0) ret = -1; return ret; } static int convert_open_fs(const char *devname, struct btrfs_convert_context *cctx) { int i; for (i = 0; i < ARRAY_SIZE(convert_operations); i++) { int ret = convert_operations[i]->open_fs(cctx, devname); if (ret == 0) { cctx->convert_ops = convert_operations[i]; return ret; } } error("no file system found to convert"); return -1; } static int do_convert(const char *devname, u32 convert_flags, u32 nodesize, const char *fslabel, int progress, u64 features, u16 csum_type, char fsid[BTRFS_UUID_UNPARSED_SIZE]) { int ret; int fd = -1; u32 blocksize; struct btrfs_root *root; struct btrfs_root *image_root; struct btrfs_convert_context cctx; struct btrfs_key key; char subvol_name[SOURCE_FS_NAME_LEN + 8]; struct task_ctx ctx; char features_buf[64]; char fsid_str[BTRFS_UUID_UNPARSED_SIZE]; struct btrfs_mkfs_config mkfs_cfg; bool btrfs_sb_committed = false; memset(&mkfs_cfg, 0, sizeof(mkfs_cfg)); init_convert_context(&cctx); ret = convert_open_fs(devname, &cctx); if (ret) goto fail; ret = convert_check_state(&cctx); if (ret) warning( "source filesystem is not clean, running filesystem check is recommended"); ret = convert_read_used_space(&cctx); if (ret) goto fail; ASSERT(cctx.total_bytes != 0); blocksize = cctx.blocksize; if (blocksize < 4096) { error("block size is too small: %u < 4096", blocksize); goto fail; } if (blocksize != getpagesize()) warning( "blocksize %u is not equal to the page size %u, converted filesystem won't mount on this system", blocksize, getpagesize()); if (btrfs_check_nodesize(nodesize, blocksize, features)) goto fail; fd = open(devname, O_RDWR); if (fd < 0) { error("unable to open %s: %m", devname); goto fail; } btrfs_parse_fs_features_to_string(features_buf, features); if (features == BTRFS_MKFS_DEFAULT_FEATURES) strcat(features_buf, " (default)"); if (convert_flags & CONVERT_FLAG_COPY_FSID) { uuid_unparse(cctx.fs_uuid, mkfs_cfg.fs_uuid); if (!test_uuid_unique(mkfs_cfg.fs_uuid)) warning("non-unique UUID (copy): %s", mkfs_cfg.fs_uuid); } else if (fsid[0] == 0) { uuid_t uuid; uuid_generate(uuid); uuid_unparse(uuid, mkfs_cfg.fs_uuid); } else { memcpy(mkfs_cfg.fs_uuid, fsid, BTRFS_UUID_UNPARSED_SIZE); if (!test_uuid_unique(mkfs_cfg.fs_uuid)) warning("non-unique UUID (user set): %s", mkfs_cfg.fs_uuid); } printf("Source filesystem:\n"); printf(" Type: %s\n", cctx.convert_ops->name); printf(" Label: %s\n", cctx.label); printf(" Blocksize: %u\n", blocksize); uuid_unparse(cctx.fs_uuid, fsid_str); printf(" UUID: %s\n", fsid_str); printf("Target filesystem:\n"); printf(" Label: %s\n", fslabel); printf(" Blocksize: %u\n", blocksize); printf(" Nodesize: %u\n", nodesize); printf(" UUID: %s\n", mkfs_cfg.fs_uuid); printf(" Checksum: %s\n", btrfs_super_csum_name(csum_type)); printf(" Features: %s\n", features_buf); printf(" Data csum: %s\n", (convert_flags & CONVERT_FLAG_DATACSUM) ? "yes" : "no"); printf(" Inline data: %s\n", (convert_flags & CONVERT_FLAG_INLINE_DATA) ? "yes" : "no"); printf(" Copy xattr: %s\n", (convert_flags & CONVERT_FLAG_XATTR) ? "yes" : "no"); printf("Reported stats:\n"); printf(" Total space: %12llu\n", cctx.total_bytes); printf(" Free space: %12llu (%.2f%%)\n", cctx.free_bytes_initial, 100.0 * cctx.free_bytes_initial / cctx.total_bytes); printf(" Inode count: %12llu\n", cctx.inodes_count); printf(" Free inodes: %12llu\n", cctx.free_inodes_count); printf(" Block count: %12llu\n", cctx.block_count); mkfs_cfg.csum_type = csum_type; mkfs_cfg.label = cctx.label; mkfs_cfg.num_bytes = cctx.total_bytes; mkfs_cfg.nodesize = nodesize; mkfs_cfg.sectorsize = blocksize; mkfs_cfg.stripesize = blocksize; mkfs_cfg.features = features; mkfs_cfg.leaf_data_size = __BTRFS_LEAF_DATA_SIZE(nodesize); printf("Create initial btrfs filesystem\n"); ret = make_convert_btrfs(fd, &mkfs_cfg, &cctx); if (ret) { errno = -ret; error("unable to create initial ctree: %m"); goto fail; } root = open_ctree_fd(fd, devname, mkfs_cfg.super_bytenr, OPEN_CTREE_WRITES | OPEN_CTREE_TEMPORARY_SUPER); if (!root) { error("unable to open ctree"); goto fail; } ret = init_btrfs(&mkfs_cfg, root, &cctx, convert_flags); if (ret) { error("unable to setup the root tree: %d", ret); goto fail; } printf("Create %s image file\n", cctx.convert_ops->name); snprintf(subvol_name, sizeof(subvol_name), "%s_saved", cctx.convert_ops->name); key.objectid = CONV_IMAGE_SUBVOL_OBJECTID; key.offset = (u64)-1; key.type = BTRFS_ROOT_ITEM_KEY; image_root = btrfs_read_fs_root(root->fs_info, &key); if (!image_root) { error("unable to create image subvolume"); goto fail; } ret = create_image(image_root, &mkfs_cfg, &cctx, fd, mkfs_cfg.num_bytes, "image", convert_flags); if (ret) { error("failed to create %s/image: %d", subvol_name, ret); goto fail; } printf("Create btrfs metadata\n"); ret = pthread_mutex_init(&ctx.mutex, NULL); if (ret) { error("failed to initialize mutex: %d", ret); goto fail; } ctx.max_copy_inodes = (cctx.inodes_count - cctx.free_inodes_count); ctx.cur_copy_inodes = 0; if (progress) { ctx.info = task_init(print_copied_inodes, after_copied_inodes, &ctx); task_start(ctx.info, NULL, NULL); } ret = copy_inodes(&cctx, root, convert_flags, &ctx); if (ret) { error("error during copy_inodes %d", ret); goto fail; } if (progress) { task_stop(ctx.info); task_deinit(ctx.info); } image_root = btrfs_mksubvol(root, subvol_name, CONV_IMAGE_SUBVOL_OBJECTID, true); if (!image_root) { error("unable to link subvolume %s", subvol_name); goto fail; } memset(root->fs_info->super_copy->label, 0, BTRFS_LABEL_SIZE); if (convert_flags & CONVERT_FLAG_COPY_LABEL) { __strncpy_null(root->fs_info->super_copy->label, cctx.label, BTRFS_LABEL_SIZE - 1); printf("Copy label '%s'\n", root->fs_info->super_copy->label); } else if (convert_flags & CONVERT_FLAG_SET_LABEL) { strcpy(root->fs_info->super_copy->label, fslabel); printf("Set label to '%s'\n", fslabel); } ret = close_ctree(root); if (ret) { error("close_ctree failed: %d", ret); goto fail; } convert_close_fs(&cctx); clean_convert_context(&cctx); /* * If this step succeed, we get a mountable btrfs. Otherwise * the source fs is left unchanged. */ ret = migrate_super_block(fd, mkfs_cfg.super_bytenr); if (ret) { error("unable to migrate super block: %d", ret); goto fail; } btrfs_sb_committed = true; root = open_ctree_fd(fd, devname, 0, OPEN_CTREE_WRITES | OPEN_CTREE_TEMPORARY_SUPER); if (!root) { error("unable to open ctree for finalization"); goto fail; } root->fs_info->finalize_on_close = 1; close_ctree(root); close(fd); printf("Conversion complete\n"); return 0; fail: clean_convert_context(&cctx); if (fd != -1) close(fd); if (btrfs_sb_committed) warning( "error during conversion, filesystem is partially created but not finalized and not mountable"); else warning( "error during conversion, the original filesystem is not modified"); return -1; } /* * Read out data of convert image which is in btrfs reserved ranges so we can * use them to overwrite the ranges during rollback. */ static int read_reserved_ranges(struct btrfs_root *root, u64 ino, u64 total_bytes, char *reserved_ranges[]) { int i; int ret = 0; for (i = 0; i < ARRAY_SIZE(btrfs_reserved_ranges); i++) { const struct simple_range *range = &btrfs_reserved_ranges[i]; if (range->start + range->len >= total_bytes) break; ret = btrfs_read_file(root, ino, range->start, range->len, reserved_ranges[i]); if (ret < range->len) { error( "failed to read data of convert image, offset=%llu len=%llu ret=%d", range->start, range->len, ret); if (ret >= 0) ret = -EIO; break; } ret = 0; } return ret; } static bool is_subset_of_reserved_ranges(u64 start, u64 len) { int i; bool ret = false; for (i = 0; i < ARRAY_SIZE(btrfs_reserved_ranges); i++) { const struct simple_range *range = &btrfs_reserved_ranges[i]; if (start >= range->start && start + len <= range_end(range)) { ret = true; break; } } return ret; } static bool is_chunk_direct_mapped(struct btrfs_fs_info *fs_info, u64 start) { struct cache_extent *ce; struct map_lookup *map; bool ret = false; ce = search_cache_extent(&fs_info->mapping_tree.cache_tree, start); if (!ce) goto out; if (ce->start > start || ce->start + ce->size < start) goto out; map = container_of(ce, struct map_lookup, ce); /* Not SINGLE chunk */ if (map->num_stripes != 1) goto out; /* Chunk's logical doesn't match with physical, not 1:1 mapped */ if (map->ce.start != map->stripes[0].physical) goto out; ret = true; out: return ret; } /* * Iterate all file extents of the convert image. * * All file extents except ones in btrfs_reserved_ranges must be mapped 1:1 * on disk. (Means their file_offset must match their on disk bytenr) * * File extents in reserved ranges can be relocated to other place, and in * that case we will read them out for later use. */ static int check_convert_image(struct btrfs_root *image_root, u64 ino, u64 total_size, char *reserved_ranges[]) { struct btrfs_key key; struct btrfs_path path; struct btrfs_fs_info *fs_info = image_root->fs_info; u64 checked_bytes = 0; int ret; key.objectid = ino; key.offset = 0; key.type = BTRFS_EXTENT_DATA_KEY; btrfs_init_path(&path); ret = btrfs_search_slot(NULL, image_root, &key, &path, 0, 0); /* * It's possible that some fs doesn't store any (including sb) * data into 0~1M range, and NO_HOLES is enabled. * * So we only need to check if ret < 0 */ if (ret < 0) { errno = -ret; error("failed to iterate file extents at offset 0: %m"); btrfs_release_path(&path); return ret; } /* Loop from the first file extents */ while (1) { struct btrfs_file_extent_item *fi; struct extent_buffer *leaf = path.nodes[0]; u64 disk_bytenr; u64 file_offset; u64 ram_bytes; int slot = path.slots[0]; if (slot >= btrfs_header_nritems(leaf)) goto next; btrfs_item_key_to_cpu(leaf, &key, slot); /* * Iteration is done, exit normally, we have extra check out of * the loop */ if (key.objectid != ino || key.type != BTRFS_EXTENT_DATA_KEY) { ret = 0; break; } file_offset = key.offset; fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item); if (btrfs_file_extent_type(leaf, fi) != BTRFS_FILE_EXTENT_REG) { ret = -EINVAL; error( "ino %llu offset %llu doesn't have a regular file extent", ino, file_offset); break; } if (btrfs_file_extent_compression(leaf, fi) || btrfs_file_extent_encryption(leaf, fi) || btrfs_file_extent_other_encoding(leaf, fi)) { ret = -EINVAL; error( "ino %llu offset %llu doesn't have a plain file extent", ino, file_offset); break; } disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi); ram_bytes = btrfs_file_extent_ram_bytes(leaf, fi); checked_bytes += ram_bytes; /* Skip hole */ if (disk_bytenr == 0) goto next; /* * Most file extents must be 1:1 mapped, which means 2 things: * 1) File extent file offset == disk_bytenr * 2) That data chunk's logical == chunk's physical * * So file extent's file offset == physical position on disk. * * And after rolling back btrfs reserved range, other part * remains what old fs used to be. */ if (file_offset != disk_bytenr || !is_chunk_direct_mapped(fs_info, disk_bytenr)) { /* * Only file extent in btrfs reserved ranges are * allowed to be non-1:1 mapped */ if (!is_subset_of_reserved_ranges(file_offset, ram_bytes)) { ret = -EINVAL; error( "ino %llu offset %llu file extent should not be relocated", ino, file_offset); break; } } next: ret = btrfs_next_item(image_root, &path); if (ret) { if (ret > 0) ret = 0; break; } } btrfs_release_path(&path); if (ret) return ret; /* * For HOLES mode (without NO_HOLES), we must ensure file extents * cover the whole range of the image */ if (!ret && !btrfs_fs_incompat(fs_info, NO_HOLES)) { if (checked_bytes != total_size) { ret = -EINVAL; error("inode %llu has some file extents not checked", ino); return ret; } } /* So far so good, read old data located in btrfs reserved ranges */ ret = read_reserved_ranges(image_root, ino, total_size, reserved_ranges); return ret; } /* * btrfs rollback is just reverted convert: * |<---------------Btrfs fs------------------------------>| * |<- Old data chunk ->|< new chunk (D/M/S)>|<- ODC ->| * |<-Old-FE->| |<-Old-FE->|<- Btrfs extents ->|<-Old-FE->| * || * \/ * |<------------------Old fs----------------------------->| * |<- used ->| |<- used ->| |<- used ->| * * However things are much easier than convert, we don't really need to * do the complex space calculation, but only to handle btrfs reserved space * * |<---------------------------Btrfs fs----------------------------->| * | RSV 1 | | Old | | RSV 2 | | Old | | RSV 3 | * | 0~1M | | Fs | | SB2 + 64K | | Fs | | SB3 + 64K | * * On the other hand, the converted fs image in btrfs is a completely * valid old fs. * * |<-----------------Converted fs image in btrfs-------------------->| * | RSV 1 | | Old | | RSV 2 | | Old | | RSV 3 | * | Relocated | | Fs | | Relocated | | Fs | | Relocated | * * Used space in fs image should be at the same physical position on disk. * We only need to recover the data in reserved ranges, so the whole * old fs is back. * * The idea to rollback is also straightforward, we just "read" out the data * of reserved ranges, and write them back to there they should be. * Then the old fs is back. */ static int do_rollback(const char *devname) { struct btrfs_root *root; struct btrfs_root *image_root; struct btrfs_fs_info *fs_info; struct btrfs_key key; struct btrfs_path path; struct btrfs_dir_item *dir; struct btrfs_inode_item *inode_item; struct btrfs_root_ref *root_ref_item; char *image_name = "image"; char dir_name[PATH_MAX]; int name_len; char fsid_str[BTRFS_UUID_UNPARSED_SIZE]; char *reserved_ranges[ARRAY_SIZE(btrfs_reserved_ranges)] = { NULL }; u64 total_bytes; u64 fsize; u64 root_dir; u64 ino; int fd = -1; int ret; int i; printf("Open filesystem for rollback:\n"); for (i = 0; i < ARRAY_SIZE(btrfs_reserved_ranges); i++) { const struct simple_range *range = &btrfs_reserved_ranges[i]; reserved_ranges[i] = calloc(1, range->len); if (!reserved_ranges[i]) { ret = -ENOMEM; goto free_mem; } } fd = open(devname, O_RDWR); if (fd < 0) { error("unable to open %s: %m", devname); ret = -EIO; goto free_mem; } fsize = lseek(fd, 0, SEEK_END); /* * For rollback, we don't really need to write anything so open it * read-only. The write part will happen after we close the * filesystem. */ root = open_ctree_fd(fd, devname, 0, 0); if (!root) { error("unable to open ctree"); ret = -EIO; goto free_mem; } fs_info = root->fs_info; printf(" Label: %s\n", fs_info->super_copy->label); uuid_unparse(fs_info->super_copy->fsid, fsid_str); printf(" UUID: %s\n", fsid_str); /* * Search root backref first, or after subvolume deletion (orphan), * we can still rollback the image. */ key.objectid = CONV_IMAGE_SUBVOL_OBJECTID; key.type = BTRFS_ROOT_BACKREF_KEY; key.offset = BTRFS_FS_TREE_OBJECTID; btrfs_init_path(&path); ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, &path, 0, 0); if (ret > 0) { error("unable to find source fs image subvolume, is it deleted?"); ret = -ENOENT; goto close_fs; } else if (ret < 0) { errno = -ret; error("failed to find source fs image subvolume: %m"); goto close_fs; } /* (256 ROOT_BACKREF 5) */ /* root backref key dirid 256 sequence 3 name ext2_saved */ root_ref_item = btrfs_item_ptr(path.nodes[0], path.slots[0], struct btrfs_root_ref); name_len = btrfs_root_ref_name_len(path.nodes[0], root_ref_item); if (name_len > sizeof(dir_name)) name_len = sizeof(dir_name) - 1; read_extent_buffer(path.nodes[0], dir_name, (unsigned long)(root_ref_item + 1), name_len); dir_name[sizeof(dir_name) - 1] = 0; printf(" Restoring from: %s/%s\n", dir_name, image_name); btrfs_release_path(&path); /* Search convert subvolume */ key.objectid = CONV_IMAGE_SUBVOL_OBJECTID; key.type = BTRFS_ROOT_ITEM_KEY; key.offset = (u64)-1; image_root = btrfs_read_fs_root(fs_info, &key); if (IS_ERR(image_root)) { ret = PTR_ERR(image_root); errno = -ret; error("failed to open convert image subvolume: %m"); goto close_fs; } /* Search the image file */ root_dir = btrfs_root_dirid(&image_root->root_item); dir = btrfs_lookup_dir_item(NULL, image_root, &path, root_dir, image_name, strlen(image_name), 0); if (!dir || IS_ERR(dir)) { btrfs_release_path(&path); if (dir) ret = PTR_ERR(dir); else ret = -ENOENT; errno = -ret; error("failed to locate file %s: %m", image_name); goto close_fs; } btrfs_dir_item_key_to_cpu(path.nodes[0], dir, &key); btrfs_release_path(&path); /* Get total size of the original image */ ino = key.objectid; ret = btrfs_lookup_inode(NULL, image_root, &path, &key, 0); if (ret < 0) { btrfs_release_path(&path); errno = -ret; error("unable to find inode %llu: %m", ino); goto close_fs; } inode_item = btrfs_item_ptr(path.nodes[0], path.slots[0], struct btrfs_inode_item); total_bytes = btrfs_inode_size(path.nodes[0], inode_item); btrfs_release_path(&path); /* Check if we can rollback the image */ ret = check_convert_image(image_root, ino, total_bytes, reserved_ranges); if (ret < 0) { error("old fs image can't be rolled back"); goto close_fs; } close_fs: btrfs_release_path(&path); close_ctree_fs_info(fs_info); if (ret) goto free_mem; /* * Everything is OK, just write back old fs data into btrfs reserved * ranges * * Here, we starts from the backup blocks first, so if something goes * wrong, the fs is still mountable */ for (i = ARRAY_SIZE(btrfs_reserved_ranges) - 1; i >= 0; i--) { u64 real_size; const struct simple_range *range = &btrfs_reserved_ranges[i]; if (range_end(range) >= fsize) continue; real_size = min(range_end(range), fsize) - range->start; ret = pwrite(fd, reserved_ranges[i], real_size, range->start); if (ret < real_size) { if (ret < 0) ret = -errno; else ret = -EIO; errno = -ret; error("failed to recover range [%llu, %llu): %m", range->start, real_size); goto free_mem; } ret = 0; } free_mem: for (i = 0; i < ARRAY_SIZE(btrfs_reserved_ranges); i++) free(reserved_ranges[i]); if (ret) error("rollback failed"); else printf("Rollback succeeded\n"); return ret; } static void print_usage(void) { printf("usage: btrfs-convert [options] device\n"); printf("options:\n"); printf("\t-d|--no-datasum disable data checksum, sets NODATASUM\n"); printf("\t-i|--no-xattr ignore xattrs and ACLs\n"); printf("\t-n|--no-inline disable inlining of small files to metadata\n"); printf("\t--csum TYPE\n"); printf("\t--checksum TYPE checksum algorithm to use (default: crc32c)\n"); printf("\t-N|--nodesize SIZE set filesystem metadata nodesize\n"); printf("\t-r|--rollback roll back to the original filesystem\n"); printf("\t-l|--label LABEL set filesystem label\n"); printf("\t-L|--copy-label use label from converted filesystem\n"); printf("\t--uuid SPEC new, copy or user-defined conforming UUID\n"); printf("\t-p|--progress show converting progress (default)\n"); printf("\t-O|--features LIST comma separated list of filesystem features\n"); printf("\t--no-progress show only overview, not the detailed progress\n"); printf("\n"); printf("Supported filesystems:\n"); printf("\text2/3/4: %s\n", BTRFSCONVERT_EXT2 ? "yes" : "no"); printf("\treiserfs: %s\n", BTRFSCONVERT_REISERFS ? "yes" : "no"); } int BOX_MAIN(convert)(int argc, char *argv[]) { int ret; int packing = 1; int noxattr = 0; int datacsum = 1; u32 nodesize = max_t(u32, sysconf(_SC_PAGESIZE), BTRFS_MKFS_DEFAULT_NODE_SIZE); int rollback = 0; int copylabel = 0; int usage_error = 0; int progress = 1; char *file; char fslabel[BTRFS_LABEL_SIZE] = { 0 }; u64 features = BTRFS_MKFS_DEFAULT_FEATURES; u16 csum_type = BTRFS_CSUM_TYPE_CRC32; u32 copy_fsid = 0; char fsid[BTRFS_UUID_UNPARSED_SIZE] = {0}; crc32c_optimization_init(); printf("btrfs-convert from %s\n\n", PACKAGE_STRING); while(1) { enum { GETOPT_VAL_NO_PROGRESS = GETOPT_VAL_FIRST, GETOPT_VAL_CHECKSUM, GETOPT_VAL_UUID }; static const struct option long_options[] = { { "no-progress", no_argument, NULL, GETOPT_VAL_NO_PROGRESS }, { "no-datasum", no_argument, NULL, 'd' }, { "no-inline", no_argument, NULL, 'n' }, { "no-xattr", no_argument, NULL, 'i' }, { "checksum", required_argument, NULL, GETOPT_VAL_CHECKSUM }, { "csum", required_argument, NULL, GETOPT_VAL_CHECKSUM }, { "rollback", no_argument, NULL, 'r' }, { "features", required_argument, NULL, 'O' }, { "progress", no_argument, NULL, 'p' }, { "label", required_argument, NULL, 'l' }, { "copy-label", no_argument, NULL, 'L' }, { "uuid", required_argument, NULL, GETOPT_VAL_UUID }, { "nodesize", required_argument, NULL, 'N' }, { "help", no_argument, NULL, GETOPT_VAL_HELP}, { NULL, 0, NULL, 0 } }; int c = getopt_long(argc, argv, "dinN:rl:LpO:", long_options, NULL); if (c < 0) break; switch(c) { case 'd': datacsum = 0; break; case 'i': noxattr = 1; break; case 'n': packing = 0; break; case 'N': nodesize = parse_size_from_string(optarg); break; case 'r': rollback = 1; break; case 'l': copylabel = CONVERT_FLAG_SET_LABEL; if (strlen(optarg) >= BTRFS_LABEL_SIZE) { warning( "label too long, trimmed to %d bytes", BTRFS_LABEL_SIZE - 1); } __strncpy_null(fslabel, optarg, BTRFS_LABEL_SIZE - 1); break; case 'L': copylabel = CONVERT_FLAG_COPY_LABEL; break; case 'p': progress = 1; break; case 'O': { char *orig = strdup(optarg); char *tmp = orig; tmp = btrfs_parse_fs_features(tmp, &features); if (tmp) { error("unrecognized filesystem feature: %s", tmp); free(orig); exit(1); } free(orig); if (features & BTRFS_FEATURE_LIST_ALL) { btrfs_list_all_fs_features( ~BTRFS_CONVERT_ALLOWED_FEATURES); exit(0); } if (features & ~BTRFS_CONVERT_ALLOWED_FEATURES) { char buf[64]; btrfs_parse_fs_features_to_string(buf, features & ~BTRFS_CONVERT_ALLOWED_FEATURES); error("features not allowed for convert: %s", buf); exit(1); } break; } case GETOPT_VAL_NO_PROGRESS: progress = 0; break; case GETOPT_VAL_CHECKSUM: csum_type = parse_csum_type(optarg); break; case GETOPT_VAL_UUID: copy_fsid = 0; fsid[0] = 0; if (strcmp(optarg, "copy") == 0) { copy_fsid = CONVERT_FLAG_COPY_FSID; } else if (strcmp(optarg, "new") == 0) { /* Generated later */ } else { uuid_t uuid; if (uuid_parse(optarg, uuid) != 0) { error("invalid UUID: %s\n", optarg); return 1; } strncpy(fsid, optarg, sizeof(fsid)); } break; case GETOPT_VAL_HELP: default: print_usage(); return c != GETOPT_VAL_HELP; } } set_argv0(argv); if (check_argc_exact(argc - optind, 1)) { print_usage(); return 1; } if (rollback && (!datacsum || noxattr || !packing)) { fprintf(stderr, "Usage error: -d, -i, -n options do not apply to rollback\n"); usage_error++; } if (usage_error) { print_usage(); return 1; } file = argv[optind]; ret = check_mounted(file); if (ret < 0) { errno = -ret; error("could not check mount status: %m"); return 1; } else if (ret) { error("%s is mounted", file); return 1; } if (rollback) { ret = do_rollback(file); } else { u32 cf = 0; cf |= datacsum ? CONVERT_FLAG_DATACSUM : 0; cf |= packing ? CONVERT_FLAG_INLINE_DATA : 0; cf |= noxattr ? 0 : CONVERT_FLAG_XATTR; cf |= copy_fsid; cf |= copylabel; ret = do_convert(file, cf, nodesize, fslabel, progress, features, csum_type, fsid); } if (ret) return 1; return 0; }