From b70cb0d0a21394d5d6b00b51f064115c2724cea8 Mon Sep 17 00:00:00 2001 From: Dimitri John Ledkov Date: Mon, 19 Feb 2018 15:51:31 +0000 Subject: New upstream release --- mkfs/rootdir.c | 955 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 955 insertions(+) create mode 100644 mkfs/rootdir.c (limited to 'mkfs/rootdir.c') diff --git a/mkfs/rootdir.c b/mkfs/rootdir.c new file mode 100644 index 00000000..e06b65ac --- /dev/null +++ b/mkfs/rootdir.c @@ -0,0 +1,955 @@ +/* + * Copyright (C) 2017 SUSE. 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. + */ + +#include "kerncompat.h" +#include "androidcompat.h" + +#include +#include +#include +#include +#include +#include +#include +#include +#include "ctree.h" +#include "volumes.h" +#include "internal.h" +#include "disk-io.h" +#include "messages.h" +#include "transaction.h" +#include "utils.h" +#include "mkfs/rootdir.h" +#include "mkfs/common.h" +#include "send-utils.h" + +static u32 fs_block_size; + +static u64 index_cnt = 2; + +/* + * Size estimate will be done using the following data: + * 1) Number of inodes + * Since we will later shrink the fs, over-estimate is completely fine here + * as long as our estimate ensures we can populate the image without ENOSPC. + * So we only record how many inodes there are, and account the maximum + * space for each inode. + * + * 2) Data space for each (regular) inode + * To estimate data chunk size. + * Don't care if it can fit as an inline extent. + * Always round them up to sectorsize. + */ +static u64 ftw_meta_nr_inode; +static u64 ftw_data_size; + +static int add_directory_items(struct btrfs_trans_handle *trans, + struct btrfs_root *root, u64 objectid, + ino_t parent_inum, const char *name, + struct stat *st, int *dir_index_cnt) +{ + int ret; + int name_len; + struct btrfs_key location; + u8 filetype = 0; + + name_len = strlen(name); + + location.objectid = objectid; + location.offset = 0; + location.type = BTRFS_INODE_ITEM_KEY; + + if (S_ISDIR(st->st_mode)) + filetype = BTRFS_FT_DIR; + if (S_ISREG(st->st_mode)) + filetype = BTRFS_FT_REG_FILE; + if (S_ISLNK(st->st_mode)) + filetype = BTRFS_FT_SYMLINK; + if (S_ISSOCK(st->st_mode)) + filetype = BTRFS_FT_SOCK; + if (S_ISCHR(st->st_mode)) + filetype = BTRFS_FT_CHRDEV; + if (S_ISBLK(st->st_mode)) + filetype = BTRFS_FT_BLKDEV; + if (S_ISFIFO(st->st_mode)) + filetype = BTRFS_FT_FIFO; + + ret = btrfs_insert_dir_item(trans, root, name, name_len, + parent_inum, &location, + filetype, index_cnt); + if (ret) + return ret; + ret = btrfs_insert_inode_ref(trans, root, name, name_len, + objectid, parent_inum, index_cnt); + *dir_index_cnt = index_cnt; + index_cnt++; + + return ret; +} + +static int fill_inode_item(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct btrfs_inode_item *dst, struct stat *src) +{ + u64 blocks = 0; + u64 sectorsize = root->fs_info->sectorsize; + + /* + * btrfs_inode_item has some reserved fields + * and represents on-disk inode entry, so + * zero everything to prevent information leak + */ + memset(dst, 0, sizeof(*dst)); + + btrfs_set_stack_inode_generation(dst, trans->transid); + btrfs_set_stack_inode_size(dst, src->st_size); + btrfs_set_stack_inode_nbytes(dst, 0); + btrfs_set_stack_inode_block_group(dst, 0); + btrfs_set_stack_inode_nlink(dst, src->st_nlink); + btrfs_set_stack_inode_uid(dst, src->st_uid); + btrfs_set_stack_inode_gid(dst, src->st_gid); + btrfs_set_stack_inode_mode(dst, src->st_mode); + btrfs_set_stack_inode_rdev(dst, 0); + btrfs_set_stack_inode_flags(dst, 0); + btrfs_set_stack_timespec_sec(&dst->atime, src->st_atime); + btrfs_set_stack_timespec_nsec(&dst->atime, 0); + btrfs_set_stack_timespec_sec(&dst->ctime, src->st_ctime); + btrfs_set_stack_timespec_nsec(&dst->ctime, 0); + btrfs_set_stack_timespec_sec(&dst->mtime, src->st_mtime); + btrfs_set_stack_timespec_nsec(&dst->mtime, 0); + btrfs_set_stack_timespec_sec(&dst->otime, 0); + btrfs_set_stack_timespec_nsec(&dst->otime, 0); + + if (S_ISDIR(src->st_mode)) { + btrfs_set_stack_inode_size(dst, 0); + btrfs_set_stack_inode_nlink(dst, 1); + } + if (S_ISREG(src->st_mode)) { + btrfs_set_stack_inode_size(dst, (u64)src->st_size); + if (src->st_size <= BTRFS_MAX_INLINE_DATA_SIZE(root->fs_info)) + btrfs_set_stack_inode_nbytes(dst, src->st_size); + else { + blocks = src->st_size / sectorsize; + if (src->st_size % sectorsize) + blocks += 1; + blocks *= sectorsize; + btrfs_set_stack_inode_nbytes(dst, blocks); + } + } + if (S_ISLNK(src->st_mode)) + btrfs_set_stack_inode_nbytes(dst, src->st_size + 1); + + return 0; +} + +static int directory_select(const struct direct *entry) +{ + if (entry->d_name[0] == '.' && + (entry->d_name[1] == 0 || + (entry->d_name[1] == '.' && entry->d_name[2] == 0))) + return 0; + return 1; +} + +static void free_namelist(struct direct **files, int count) +{ + int i; + + if (count < 0) + return; + + for (i = 0; i < count; ++i) + free(files[i]); + free(files); +} + +static u64 calculate_dir_inode_size(const char *dirname) +{ + int count, i; + struct direct **files, *cur_file; + u64 dir_inode_size = 0; + + count = scandir(dirname, &files, directory_select, NULL); + + for (i = 0; i < count; i++) { + cur_file = files[i]; + dir_inode_size += strlen(cur_file->d_name); + } + + free_namelist(files, count); + + dir_inode_size *= 2; + return dir_inode_size; +} + +static int add_inode_items(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct stat *st, const char *name, + u64 self_objectid, + struct btrfs_inode_item *inode_ret) +{ + int ret; + struct btrfs_inode_item btrfs_inode; + u64 objectid; + u64 inode_size = 0; + + fill_inode_item(trans, root, &btrfs_inode, st); + objectid = self_objectid; + + if (S_ISDIR(st->st_mode)) { + inode_size = calculate_dir_inode_size(name); + btrfs_set_stack_inode_size(&btrfs_inode, inode_size); + } + + ret = btrfs_insert_inode(trans, root, objectid, &btrfs_inode); + + *inode_ret = btrfs_inode; + return ret; +} + +static int add_xattr_item(struct btrfs_trans_handle *trans, + struct btrfs_root *root, u64 objectid, + const char *file_name) +{ + int ret; + int cur_name_len; + char xattr_list[XATTR_LIST_MAX]; + char *cur_name; + char cur_value[XATTR_SIZE_MAX]; + char delimiter = '\0'; + char *next_location = xattr_list; + + ret = llistxattr(file_name, xattr_list, XATTR_LIST_MAX); + if (ret < 0) { + if (errno == ENOTSUP) + return 0; + error("getting a list of xattr failed for %s: %s", file_name, + strerror(errno)); + return ret; + } + if (ret == 0) + return ret; + + cur_name = strtok(xattr_list, &delimiter); + while (cur_name != NULL) { + cur_name_len = strlen(cur_name); + next_location += cur_name_len + 1; + + ret = getxattr(file_name, cur_name, cur_value, XATTR_SIZE_MAX); + if (ret < 0) { + if (errno == ENOTSUP) + return 0; + error("gettig a xattr value failed for %s attr %s: %s", + file_name, cur_name, strerror(errno)); + return ret; + } + + ret = btrfs_insert_xattr_item(trans, root, cur_name, + cur_name_len, cur_value, + ret, objectid); + if (ret) { + error("inserting a xattr item failed for %s: %s", + file_name, strerror(-ret)); + } + + cur_name = strtok(next_location, &delimiter); + } + + return ret; +} + +static int add_symbolic_link(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + u64 objectid, const char *path_name) +{ + int ret; + char buf[PATH_MAX]; + + ret = readlink(path_name, buf, sizeof(buf)); + if (ret <= 0) { + error("readlink failed for %s: %s", path_name, strerror(errno)); + goto fail; + } + if (ret >= sizeof(buf)) { + error("symlink too long for %s", path_name); + ret = -1; + goto fail; + } + + buf[ret] = '\0'; /* readlink does not do it for us */ + ret = btrfs_insert_inline_extent(trans, root, objectid, 0, + buf, ret + 1); +fail: + return ret; +} + +static int add_file_items(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct btrfs_inode_item *btrfs_inode, u64 objectid, + struct stat *st, const char *path_name) +{ + int ret = -1; + ssize_t ret_read; + u64 bytes_read = 0; + struct btrfs_key key; + int blocks; + u32 sectorsize = root->fs_info->sectorsize; + u64 first_block = 0; + u64 file_pos = 0; + u64 cur_bytes; + u64 total_bytes; + struct extent_buffer *eb = NULL; + int fd; + + if (st->st_size == 0) + return 0; + + fd = open(path_name, O_RDONLY); + if (fd == -1) { + error("cannot open %s: %s", path_name, strerror(errno)); + return ret; + } + + blocks = st->st_size / sectorsize; + if (st->st_size % sectorsize) + blocks += 1; + + if (st->st_size <= BTRFS_MAX_INLINE_DATA_SIZE(root->fs_info)) { + char *buffer = malloc(st->st_size); + + if (!buffer) { + ret = -ENOMEM; + goto end; + } + + ret_read = pread64(fd, buffer, st->st_size, bytes_read); + if (ret_read == -1) { + error("cannot read %s at offset %llu length %llu: %s", + path_name, (unsigned long long)bytes_read, + (unsigned long long)st->st_size, + strerror(errno)); + free(buffer); + goto end; + } + + ret = btrfs_insert_inline_extent(trans, root, objectid, 0, + buffer, st->st_size); + free(buffer); + goto end; + } + + /* round up our st_size to the FS blocksize */ + total_bytes = (u64)blocks * sectorsize; + + /* + * do our IO in extent buffers so it can work + * against any raid type + */ + eb = calloc(1, sizeof(*eb) + sectorsize); + if (!eb) { + ret = -ENOMEM; + goto end; + } + +again: + + /* + * keep our extent size at 1MB max, this makes it easier to work inside + * the tiny block groups created during mkfs + */ + cur_bytes = min(total_bytes, (u64)SZ_1M); + ret = btrfs_reserve_extent(trans, root, cur_bytes, 0, 0, (u64)-1, + &key, 1); + if (ret) + goto end; + + first_block = key.objectid; + bytes_read = 0; + + while (bytes_read < cur_bytes) { + + memset(eb->data, 0, sectorsize); + + ret_read = pread64(fd, eb->data, sectorsize, file_pos + + bytes_read); + if (ret_read == -1) { + error("cannot read %s at offset %llu length %llu: %s", + path_name, + (unsigned long long)file_pos + bytes_read, + (unsigned long long)sectorsize, + strerror(errno)); + goto end; + } + + eb->start = first_block + bytes_read; + eb->len = sectorsize; + + /* + * we're doing the csum before we record the extent, but + * that's ok + */ + ret = btrfs_csum_file_block(trans, root->fs_info->csum_root, + first_block + bytes_read + sectorsize, + first_block + bytes_read, + eb->data, sectorsize); + if (ret) + goto end; + + ret = write_and_map_eb(root->fs_info, eb); + if (ret) { + error("failed to write %s", path_name); + goto end; + } + + bytes_read += sectorsize; + } + + if (bytes_read) { + ret = btrfs_record_file_extent(trans, root, objectid, + btrfs_inode, file_pos, first_block, cur_bytes); + if (ret) + goto end; + + } + + file_pos += cur_bytes; + total_bytes -= cur_bytes; + + if (total_bytes) + goto again; + +end: + free(eb); + close(fd); + return ret; +} + +static int traverse_directory(struct btrfs_trans_handle *trans, + struct btrfs_root *root, const char *dir_name, + struct directory_name_entry *dir_head) +{ + int ret = 0; + + struct btrfs_inode_item cur_inode; + struct btrfs_inode_item *inode_item; + int count, i, dir_index_cnt; + struct direct **files; + struct stat st; + struct directory_name_entry *dir_entry, *parent_dir_entry; + struct direct *cur_file; + ino_t parent_inum, cur_inum; + ino_t highest_inum = 0; + const char *parent_dir_name; + struct btrfs_path path; + struct extent_buffer *leaf; + struct btrfs_key root_dir_key; + u64 root_dir_inode_size = 0; + + /* Add list for source directory */ + dir_entry = malloc(sizeof(struct directory_name_entry)); + if (!dir_entry) + return -ENOMEM; + dir_entry->dir_name = dir_name; + dir_entry->path = realpath(dir_name, NULL); + if (!dir_entry->path) { + error("realpath failed for %s: %s", dir_name, strerror(errno)); + ret = -1; + goto fail_no_dir; + } + + parent_inum = highest_inum + BTRFS_FIRST_FREE_OBJECTID; + dir_entry->inum = parent_inum; + list_add_tail(&dir_entry->list, &dir_head->list); + + btrfs_init_path(&path); + + root_dir_key.objectid = btrfs_root_dirid(&root->root_item); + root_dir_key.offset = 0; + root_dir_key.type = BTRFS_INODE_ITEM_KEY; + ret = btrfs_lookup_inode(trans, root, &path, &root_dir_key, 1); + if (ret) { + error("failed to lookup root dir: %d", ret); + goto fail_no_dir; + } + + leaf = path.nodes[0]; + inode_item = btrfs_item_ptr(leaf, path.slots[0], + struct btrfs_inode_item); + + root_dir_inode_size = calculate_dir_inode_size(dir_name); + btrfs_set_inode_size(leaf, inode_item, root_dir_inode_size); + btrfs_mark_buffer_dirty(leaf); + + btrfs_release_path(&path); + + do { + parent_dir_entry = list_entry(dir_head->list.next, + struct directory_name_entry, + list); + list_del(&parent_dir_entry->list); + + parent_inum = parent_dir_entry->inum; + parent_dir_name = parent_dir_entry->dir_name; + if (chdir(parent_dir_entry->path)) { + error("chdir failed for %s: %s", + parent_dir_name, strerror(errno)); + ret = -1; + goto fail_no_files; + } + + count = scandir(parent_dir_entry->path, &files, + directory_select, NULL); + if (count == -1) { + error("scandir failed for %s: %s", + parent_dir_name, strerror(errno)); + ret = -1; + goto fail; + } + + for (i = 0; i < count; i++) { + cur_file = files[i]; + + if (lstat(cur_file->d_name, &st) == -1) { + error("lstat failed for %s: %s", + cur_file->d_name, strerror(errno)); + ret = -1; + goto fail; + } + + cur_inum = st.st_ino; + ret = add_directory_items(trans, root, + cur_inum, parent_inum, + cur_file->d_name, + &st, &dir_index_cnt); + if (ret) { + error("unable to add directory items for %s: %d", + cur_file->d_name, ret); + goto fail; + } + + ret = add_inode_items(trans, root, &st, + cur_file->d_name, cur_inum, + &cur_inode); + if (ret == -EEXIST) { + if (st.st_nlink <= 1) { + error( + "item %s already exists but has wrong st_nlink %lu <= 1", + cur_file->d_name, + (unsigned long)st.st_nlink); + goto fail; + } + continue; + } + if (ret) { + error("unable to add inode items for %s: %d", + cur_file->d_name, ret); + goto fail; + } + + ret = add_xattr_item(trans, root, + cur_inum, cur_file->d_name); + if (ret) { + error("unable to add xattr items for %s: %d", + cur_file->d_name, ret); + if (ret != -ENOTSUP) + goto fail; + } + + if (S_ISDIR(st.st_mode)) { + char tmp[PATH_MAX]; + + dir_entry = malloc(sizeof(*dir_entry)); + if (!dir_entry) { + ret = -ENOMEM; + goto fail; + } + dir_entry->dir_name = cur_file->d_name; + if (path_cat_out(tmp, parent_dir_entry->path, + cur_file->d_name)) { + error("invalid path: %s/%s", + parent_dir_entry->path, + cur_file->d_name); + ret = -EINVAL; + goto fail; + } + dir_entry->path = strdup(tmp); + if (!dir_entry->path) { + error("not enough memory to store path"); + ret = -ENOMEM; + goto fail; + } + dir_entry->inum = cur_inum; + list_add_tail(&dir_entry->list, + &dir_head->list); + } else if (S_ISREG(st.st_mode)) { + ret = add_file_items(trans, root, &cur_inode, + cur_inum, &st, + cur_file->d_name); + if (ret) { + error("unable to add file items for %s: %d", + cur_file->d_name, ret); + goto fail; + } + } else if (S_ISLNK(st.st_mode)) { + ret = add_symbolic_link(trans, root, + cur_inum, cur_file->d_name); + if (ret) { + error("unable to add symlink for %s: %d", + cur_file->d_name, ret); + goto fail; + } + } + } + + free_namelist(files, count); + free(parent_dir_entry->path); + free(parent_dir_entry); + + index_cnt = 2; + + } while (!list_empty(&dir_head->list)); + +out: + return !!ret; +fail: + free_namelist(files, count); +fail_no_files: + free(parent_dir_entry); + goto out; +fail_no_dir: + free(dir_entry); + goto out; +} + +int btrfs_mkfs_fill_dir(const char *source_dir, struct btrfs_root *root, + bool verbose) +{ + int ret; + struct btrfs_trans_handle *trans; + struct stat root_st; + struct directory_name_entry dir_head; + struct directory_name_entry *dir_entry = NULL; + + ret = lstat(source_dir, &root_st); + if (ret) { + error("unable to lstat %s: %s", source_dir, strerror(errno)); + ret = -errno; + goto out; + } + + INIT_LIST_HEAD(&dir_head.list); + + trans = btrfs_start_transaction(root, 1); + BUG_ON(IS_ERR(trans)); + ret = traverse_directory(trans, root, source_dir, &dir_head); + if (ret) { + error("unable to traverse directory %s: %d", source_dir, ret); + goto fail; + } + ret = btrfs_commit_transaction(trans, root); + if (ret) { + error("transaction commit failed: %d", ret); + goto out; + } + + if (verbose) + printf("Making image is completed.\n"); + return 0; +fail: + /* + * Since we don't have btrfs_abort_transaction() yet, uncommitted trans + * will trigger a BUG_ON(). + * + * However before mkfs is fully finished, the magic number is invalid, + * so even we commit transaction here, the fs still can't be mounted. + * + * To do a graceful error out, here we commit transaction as a + * workaround. + * Since we have already hit some problem, the return value doesn't + * matter now. + */ + btrfs_commit_transaction(trans, root); + while (!list_empty(&dir_head.list)) { + dir_entry = list_entry(dir_head.list.next, + struct directory_name_entry, list); + list_del(&dir_entry->list); + free(dir_entry->path); + free(dir_entry); + } +out: + return ret; +} + +static int ftw_add_entry_size(const char *fpath, const struct stat *st, + int type) +{ + /* + * Failed to read the directory, mostly due to EPERM. Abort ASAP, so + * we don't need to populate the fs. + */ + if (type == FTW_DNR || type == FTW_NS) + return -EPERM; + + if (S_ISREG(st->st_mode)) + ftw_data_size += round_up(st->st_size, fs_block_size); + ftw_meta_nr_inode++; + + return 0; +} + +u64 btrfs_mkfs_size_dir(const char *dir_name, u32 sectorsize, u64 min_dev_size, + u64 meta_profile, u64 data_profile) +{ + u64 total_size = 0; + int ret; + + u64 meta_size = 0; /* Based on @ftw_meta_nr_inode */ + u64 meta_chunk_size = 0; /* Based on @meta_size */ + u64 data_chunk_size = 0; /* Based on @ftw_data_size */ + + u64 meta_threshold = SZ_8M; + u64 data_threshold = SZ_8M; + + float data_multipler = 1; + float meta_multipler = 1; + + fs_block_size = sectorsize; + ftw_data_size = 0; + ftw_meta_nr_inode = 0; + ret = ftw(dir_name, ftw_add_entry_size, 10); + if (ret < 0) { + error("ftw subdir walk of %s failed: %s", dir_name, + strerror(errno)); + exit(1); + } + + + /* + * Maximum metadata useage for every inode, which will be PATH_MAX + * for the following items: + * 1) DIR_ITEM + * 2) DIR_INDEX + * 3) INODE_REF + * + * Plus possible inline extent size, which is sectorsize. + * + * And finally, allow metadata usage to increase with data size. + * Follow the old kernel 8:1 data:meta ratio. + * This is especially important for --rootdir, as the file extent size + * upper limit is 1M, instead of 128M in kernel. + * This can bump meta usage easily. + */ + meta_size = ftw_meta_nr_inode * (PATH_MAX * 3 + sectorsize) + + ftw_data_size / 8; + + /* Minimal chunk size from btrfs_alloc_chunk(). */ + if (meta_profile & BTRFS_BLOCK_GROUP_DUP) { + meta_threshold = SZ_32M; + meta_multipler = 2; + } + if (data_profile & BTRFS_BLOCK_GROUP_DUP) { + data_threshold = SZ_64M; + data_multipler = 2; + } + + /* + * Only when the usage is larger than the minimal chunk size (threshold) + * we need to allocate new chunk, or the initial chunk in the image is + * large enough. + */ + if (meta_size > meta_threshold) + meta_chunk_size = (round_up(meta_size, meta_threshold) - + meta_threshold) * meta_multipler; + if (ftw_data_size > data_threshold) + data_chunk_size = (round_up(ftw_data_size, data_threshold) - + data_threshold) * data_multipler; + + total_size = data_chunk_size + meta_chunk_size + min_dev_size; + return total_size; +} + +/* + * Get the end position of the last device extent for given @devid; + * @size_ret is exclsuive (means it should be aligned to sectorsize) + */ +static int get_device_extent_end(struct btrfs_fs_info *fs_info, + u64 devid, u64 *size_ret) +{ + struct btrfs_root *dev_root = fs_info->dev_root; + struct btrfs_key key; + struct btrfs_path path; + struct btrfs_dev_extent *de; + int ret; + + key.objectid = devid; + key.type = BTRFS_DEV_EXTENT_KEY; + key.offset = (u64)-1; + + btrfs_init_path(&path); + ret = btrfs_search_slot(NULL, dev_root, &key, &path, 0, 0); + /* Not really possible */ + BUG_ON(ret == 0); + + ret = btrfs_previous_item(dev_root, &path, devid, BTRFS_DEV_EXTENT_KEY); + if (ret < 0) + goto out; + + /* No dev_extent at all, not really possible for rootdir case */ + if (ret > 0) { + *size_ret = 0; + ret = -EUCLEAN; + goto out; + } + + btrfs_item_key_to_cpu(path.nodes[0], &key, path.slots[0]); + de = btrfs_item_ptr(path.nodes[0], path.slots[0], + struct btrfs_dev_extent); + *size_ret = key.offset + btrfs_dev_extent_length(path.nodes[0], de); +out: + btrfs_release_path(&path); + + return ret; +} + +/* + * Set device size to @new_size. + * + * Only used for --rootdir option. + * We will need to reset the following values: + * 1) dev item in chunk tree + * 2) super->dev_item + * 3) super->total_bytes + */ +static int set_device_size(struct btrfs_fs_info *fs_info, + struct btrfs_device *device, u64 new_size) +{ + struct btrfs_root *chunk_root = fs_info->chunk_root; + struct btrfs_trans_handle *trans; + struct btrfs_dev_item *di; + struct btrfs_path path; + struct btrfs_key key; + int ret; + + /* + * Update in-meory device->total_bytes, so that at trans commit time, + * super->dev_item will also get updated + */ + device->total_bytes = new_size; + btrfs_init_path(&path); + + /* Update device item in chunk tree */ + trans = btrfs_start_transaction(chunk_root, 1); + if (IS_ERR(trans)) { + ret = PTR_ERR(trans); + error("failed to start transaction: %d (%s)", ret, + strerror(-ret)); + return ret; + } + key.objectid = BTRFS_DEV_ITEMS_OBJECTID; + key.type = BTRFS_DEV_ITEM_KEY; + key.offset = device->devid; + + ret = btrfs_search_slot(trans, chunk_root, &key, &path, 0, 1); + if (ret < 0) + goto err; + if (ret > 0) + ret = -ENOENT; + di = btrfs_item_ptr(path.nodes[0], path.slots[0], + struct btrfs_dev_item); + btrfs_set_device_total_bytes(path.nodes[0], di, new_size); + btrfs_mark_buffer_dirty(path.nodes[0]); + + /* + * Update super->total_bytes, since it's only used for --rootdir, + * there is only one device, just use the @new_size. + */ + btrfs_set_super_total_bytes(fs_info->super_copy, new_size); + + /* + * Commit transaction to reflect the updated super->total_bytes and + * super->dev_item + */ + ret = btrfs_commit_transaction(trans, chunk_root); + if (ret < 0) + error("failed to commit current transaction: %d (%s)", + ret, strerror(-ret)); + btrfs_release_path(&path); + return ret; + +err: + btrfs_release_path(&path); + /* + * Committing the transaction here won't cause problems since the fs + * still has an invalid magic number, and something wrong already + * happened, we don't care the return value anyway. + */ + btrfs_commit_transaction(trans, chunk_root); + return ret; +} + +int btrfs_mkfs_shrink_fs(struct btrfs_fs_info *fs_info, u64 *new_size_ret, + bool shrink_file_size) +{ + u64 new_size; + struct btrfs_device *device; + struct list_head *cur; + struct stat64 file_stat; + int nr_devs = 0; + int ret; + + list_for_each(cur, &fs_info->fs_devices->devices) + nr_devs++; + + if (nr_devs > 1) { + error("cannot shrink fs with more than 1 device"); + return -ENOTTY; + } + + ret = get_device_extent_end(fs_info, 1, &new_size); + if (ret < 0) { + error("failed to get minimal device size: %d (%s)", + ret, strerror(-ret)); + return ret; + } + + BUG_ON(!IS_ALIGNED(new_size, fs_info->sectorsize)); + + device = list_entry(fs_info->fs_devices->devices.next, + struct btrfs_device, dev_list); + ret = set_device_size(fs_info, device, new_size); + if (ret < 0) + return ret; + if (new_size_ret) + *new_size_ret = new_size; + + if (shrink_file_size) { + ret = fstat64(device->fd, &file_stat); + if (ret < 0) { + error("failed to stat devid %llu: %s", device->devid, + strerror(errno)); + return ret; + } + if (!S_ISREG(file_stat.st_mode)) + return ret; + ret = ftruncate64(device->fd, new_size); + if (ret < 0) { + error("failed to truncate device file of devid %llu: %s", + device->devid, strerror(errno)); + return ret; + } + } + return ret; +} -- cgit v1.2.3