diff options
Diffstat (limited to 'utils.c')
| -rw-r--r-- | utils.c | 4133 |
1 files changed, 4133 insertions, 0 deletions
diff --git a/utils.c b/utils.c new file mode 100644 index 00000000..578fdb04 --- /dev/null +++ b/utils.c @@ -0,0 +1,4133 @@ +/* + * Copyright (C) 2007 Oracle. All rights reserved. + * Copyright (C) 2008 Morey Roof. 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. + */ + +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <sys/ioctl.h> +#include <sys/mount.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <uuid/uuid.h> +#include <fcntl.h> +#include <unistd.h> +#include <mntent.h> +#include <ctype.h> +#include <linux/loop.h> +#include <linux/major.h> +#include <linux/kdev_t.h> +#include <limits.h> +#include <blkid/blkid.h> +#include <sys/vfs.h> +#include <sys/statfs.h> +#include <linux/magic.h> +#include <getopt.h> + +#include "kerncompat.h" +#include "radix-tree.h" +#include "ctree.h" +#include "disk-io.h" +#include "transaction.h" +#include "crc32c.h" +#include "utils.h" +#include "volumes.h" +#include "ioctl.h" +#include "commands.h" + +#ifndef BLKDISCARD +#define BLKDISCARD _IO(0x12,119) +#endif + +static int btrfs_scan_done = 0; + +static char argv0_buf[ARGV0_BUF_SIZE] = "btrfs"; + +static int rand_seed_initlized = 0; +static unsigned short rand_seed[3]; + +const char *get_argv0_buf(void) +{ + return argv0_buf; +} + +void fixup_argv0(char **argv, const char *token) +{ + int len = strlen(argv0_buf); + + snprintf(argv0_buf + len, sizeof(argv0_buf) - len, " %s", token); + argv[0] = argv0_buf; +} + +void set_argv0(char **argv) +{ + strncpy(argv0_buf, argv[0], sizeof(argv0_buf)); + argv0_buf[sizeof(argv0_buf) - 1] = 0; +} + +int check_argc_exact(int nargs, int expected) +{ + if (nargs < expected) + fprintf(stderr, "%s: too few arguments\n", argv0_buf); + if (nargs > expected) + fprintf(stderr, "%s: too many arguments\n", argv0_buf); + + return nargs != expected; +} + +int check_argc_min(int nargs, int expected) +{ + if (nargs < expected) { + fprintf(stderr, "%s: too few arguments\n", argv0_buf); + return 1; + } + + return 0; +} + +int check_argc_max(int nargs, int expected) +{ + if (nargs > expected) { + fprintf(stderr, "%s: too many arguments\n", argv0_buf); + return 1; + } + + return 0; +} + + +/* + * Discard the given range in one go + */ +static int discard_range(int fd, u64 start, u64 len) +{ + u64 range[2] = { start, len }; + + if (ioctl(fd, BLKDISCARD, &range) < 0) + return errno; + return 0; +} + +/* + * Discard blocks in the given range in 1G chunks, the process is interruptible + */ +static int discard_blocks(int fd, u64 start, u64 len) +{ + while (len > 0) { + /* 1G granularity */ + u64 chunk_size = min_t(u64, len, 1*1024*1024*1024); + int ret; + + ret = discard_range(fd, start, chunk_size); + if (ret) + return ret; + len -= chunk_size; + start += chunk_size; + } + + return 0; +} + +static u64 reference_root_table[] = { + [1] = BTRFS_ROOT_TREE_OBJECTID, + [2] = BTRFS_EXTENT_TREE_OBJECTID, + [3] = BTRFS_CHUNK_TREE_OBJECTID, + [4] = BTRFS_DEV_TREE_OBJECTID, + [5] = BTRFS_FS_TREE_OBJECTID, + [6] = BTRFS_CSUM_TREE_OBJECTID, +}; + +int test_uuid_unique(char *fs_uuid) +{ + int unique = 1; + blkid_dev_iterate iter = NULL; + blkid_dev dev = NULL; + blkid_cache cache = NULL; + + if (blkid_get_cache(&cache, NULL) < 0) { + printf("ERROR: lblkid cache get failed\n"); + return 1; + } + blkid_probe_all(cache); + iter = blkid_dev_iterate_begin(cache); + blkid_dev_set_search(iter, "UUID", fs_uuid); + + while (blkid_dev_next(iter, &dev) == 0) { + dev = blkid_verify(cache, dev); + if (dev) { + unique = 0; + break; + } + } + + blkid_dev_iterate_end(iter); + blkid_put_cache(cache); + + return unique; +} + +/* + * Reserve space from free_tree. + * The algorithm is very simple, find the first cache_extent with enough space + * and allocate from its beginning. + */ +static int reserve_free_space(struct cache_tree *free_tree, u64 len, + u64 *ret_start) +{ + struct cache_extent *cache; + int found = 0; + + BUG_ON(!ret_start); + cache = first_cache_extent(free_tree); + while (cache) { + if (cache->size > len) { + found = 1; + *ret_start = cache->start; + + cache->size -= len; + if (cache->size == 0) { + remove_cache_extent(free_tree, cache); + free(cache); + } else { + cache->start += len; + } + break; + } + cache = next_cache_extent(cache); + } + if (!found) + return -ENOSPC; + return 0; +} + +static inline int write_temp_super(int fd, struct btrfs_super_block *sb, + u64 sb_bytenr) +{ + u32 crc = ~(u32)0; + int ret; + + crc = btrfs_csum_data(NULL, (char *)sb + BTRFS_CSUM_SIZE, crc, + BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE); + btrfs_csum_final(crc, (char *)&sb->csum[0]); + ret = pwrite(fd, sb, BTRFS_SUPER_INFO_SIZE, sb_bytenr); + if (ret < BTRFS_SUPER_INFO_SIZE) + ret = (ret < 0 ? -errno : -EIO); + else + ret = 0; + return ret; +} + +/* + * Setup temporary superblock at cfg->super_bynter + * Needed info are extracted from cfg, and root_bytenr, chunk_bytenr + * + * For now sys chunk array will be empty and dev_item is empty too. + * They will be re-initialized at temp chunk tree setup. + */ +static int setup_temp_super(int fd, struct btrfs_mkfs_config *cfg, + u64 root_bytenr, u64 chunk_bytenr) +{ + unsigned char chunk_uuid[BTRFS_UUID_SIZE]; + char super_buf[BTRFS_SUPER_INFO_SIZE]; + struct btrfs_super_block *super = (struct btrfs_super_block *)super_buf; + int ret; + + /* + * We rely on cfg->chunk_uuid and cfg->fs_uuid to pass uuid + * for other functions. + * Caller must allocate space for them + */ + BUG_ON(!cfg->chunk_uuid || !cfg->fs_uuid); + memset(super_buf, 0, BTRFS_SUPER_INFO_SIZE); + cfg->num_bytes = round_down(cfg->num_bytes, cfg->sectorsize); + + if (cfg->fs_uuid && *cfg->fs_uuid) { + if (uuid_parse(cfg->fs_uuid, super->fsid) != 0) { + error("cound not parse UUID: %s", cfg->fs_uuid); + ret = -EINVAL; + goto out; + } + if (!test_uuid_unique(cfg->fs_uuid)) { + error("non-unique UUID: %s", cfg->fs_uuid); + ret = -EINVAL; + goto out; + } + } else { + uuid_generate(super->fsid); + uuid_unparse(super->fsid, cfg->fs_uuid); + } + uuid_generate(chunk_uuid); + uuid_unparse(chunk_uuid, cfg->chunk_uuid); + + btrfs_set_super_bytenr(super, cfg->super_bytenr); + btrfs_set_super_num_devices(super, 1); + btrfs_set_super_magic(super, BTRFS_MAGIC); + btrfs_set_super_generation(super, 1); + btrfs_set_super_root(super, root_bytenr); + btrfs_set_super_chunk_root(super, chunk_bytenr); + btrfs_set_super_total_bytes(super, cfg->num_bytes); + /* + * Temporary filesystem will only have 6 tree roots: + * chunk tree, root tree, extent_tree, device tree, fs tree + * and csum tree. + */ + btrfs_set_super_bytes_used(super, 6 * cfg->nodesize); + btrfs_set_super_sectorsize(super, cfg->sectorsize); + btrfs_set_super_leafsize(super, cfg->nodesize); + btrfs_set_super_nodesize(super, cfg->nodesize); + btrfs_set_super_stripesize(super, cfg->stripesize); + btrfs_set_super_csum_type(super, BTRFS_CSUM_TYPE_CRC32); + btrfs_set_super_chunk_root(super, chunk_bytenr); + btrfs_set_super_cache_generation(super, -1); + btrfs_set_super_incompat_flags(super, cfg->features); + if (cfg->label) + __strncpy_null(super->label, cfg->label, BTRFS_LABEL_SIZE - 1); + + /* Sys chunk array will be re-initialized at chunk tree init time */ + super->sys_chunk_array_size = 0; + + ret = write_temp_super(fd, super, cfg->super_bytenr); +out: + return ret; +} + +/* + * Setup an extent buffer for tree block. + */ +static int setup_temp_extent_buffer(struct extent_buffer *buf, + struct btrfs_mkfs_config *cfg, + u64 bytenr, u64 owner) +{ + unsigned char fsid[BTRFS_FSID_SIZE]; + unsigned char chunk_uuid[BTRFS_UUID_SIZE]; + int ret; + + /* We rely on cfg->fs_uuid and chunk_uuid to fsid and chunk uuid */ + BUG_ON(!cfg->fs_uuid || !cfg->chunk_uuid); + ret = uuid_parse(cfg->fs_uuid, fsid); + if (ret) + return -EINVAL; + ret = uuid_parse(cfg->chunk_uuid, chunk_uuid); + if (ret) + return -EINVAL; + + memset(buf->data, 0, cfg->nodesize); + buf->len = cfg->nodesize; + btrfs_set_header_bytenr(buf, bytenr); + btrfs_set_header_generation(buf, 1); + btrfs_set_header_backref_rev(buf, BTRFS_MIXED_BACKREF_REV); + btrfs_set_header_owner(buf, owner); + btrfs_set_header_flags(buf, BTRFS_HEADER_FLAG_WRITTEN); + write_extent_buffer(buf, chunk_uuid, btrfs_header_chunk_tree_uuid(buf), + BTRFS_UUID_SIZE); + write_extent_buffer(buf, fsid, btrfs_header_fsid(), BTRFS_FSID_SIZE); + return 0; +} + +static inline int write_temp_extent_buffer(int fd, struct extent_buffer *buf, + u64 bytenr) +{ + int ret; + + csum_tree_block_size(buf, BTRFS_CRC32_SIZE, 0); + + /* Temporary extent buffer is always mapped 1:1 on disk */ + ret = pwrite(fd, buf->data, buf->len, bytenr); + if (ret < buf->len) + ret = (ret < 0 ? ret : -EIO); + else + ret = 0; + return ret; +} + +/* + * Insert a root item for temporary tree root + * + * Only used in make_btrfs_v2(). + */ +static void insert_temp_root_item(struct extent_buffer *buf, + struct btrfs_mkfs_config *cfg, + int *slot, u32 *itemoff, u64 objectid, + u64 bytenr) +{ + struct btrfs_root_item root_item; + struct btrfs_inode_item *inode_item; + struct btrfs_disk_key disk_key; + + btrfs_set_header_nritems(buf, *slot + 1); + (*itemoff) -= sizeof(root_item); + memset(&root_item, 0, sizeof(root_item)); + inode_item = &root_item.inode; + btrfs_set_stack_inode_generation(inode_item, 1); + btrfs_set_stack_inode_size(inode_item, 3); + btrfs_set_stack_inode_nlink(inode_item, 1); + btrfs_set_stack_inode_nbytes(inode_item, cfg->nodesize); + btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755); + btrfs_set_root_refs(&root_item, 1); + btrfs_set_root_used(&root_item, cfg->nodesize); + btrfs_set_root_generation(&root_item, 1); + btrfs_set_root_bytenr(&root_item, bytenr); + + memset(&disk_key, 0, sizeof(disk_key)); + btrfs_set_disk_key_type(&disk_key, BTRFS_ROOT_ITEM_KEY); + btrfs_set_disk_key_objectid(&disk_key, objectid); + btrfs_set_disk_key_offset(&disk_key, 0); + + btrfs_set_item_key(buf, &disk_key, *slot); + btrfs_set_item_offset(buf, btrfs_item_nr(*slot), *itemoff); + btrfs_set_item_size(buf, btrfs_item_nr(*slot), sizeof(root_item)); + write_extent_buffer(buf, &root_item, + btrfs_item_ptr_offset(buf, *slot), + sizeof(root_item)); + (*slot)++; +} + +static int setup_temp_root_tree(int fd, struct btrfs_mkfs_config *cfg, + u64 root_bytenr, u64 extent_bytenr, + u64 dev_bytenr, u64 fs_bytenr, u64 csum_bytenr) +{ + struct extent_buffer *buf = NULL; + u32 itemoff = __BTRFS_LEAF_DATA_SIZE(cfg->nodesize); + int slot = 0; + int ret; + + /* + * Provided bytenr must in ascending order, or tree root will have a + * bad key order. + */ + BUG_ON(!(root_bytenr < extent_bytenr && extent_bytenr < dev_bytenr && + dev_bytenr < fs_bytenr && fs_bytenr < csum_bytenr)); + buf = malloc(sizeof(*buf) + cfg->nodesize); + if (!buf) + return -ENOMEM; + + ret = setup_temp_extent_buffer(buf, cfg, root_bytenr, + BTRFS_ROOT_TREE_OBJECTID); + if (ret < 0) + goto out; + + insert_temp_root_item(buf, cfg, &slot, &itemoff, + BTRFS_EXTENT_TREE_OBJECTID, extent_bytenr); + insert_temp_root_item(buf, cfg, &slot, &itemoff, + BTRFS_DEV_TREE_OBJECTID, dev_bytenr); + insert_temp_root_item(buf, cfg, &slot, &itemoff, + BTRFS_FS_TREE_OBJECTID, fs_bytenr); + insert_temp_root_item(buf, cfg, &slot, &itemoff, + BTRFS_CSUM_TREE_OBJECTID, csum_bytenr); + + ret = write_temp_extent_buffer(fd, buf, root_bytenr); +out: + free(buf); + return ret; +} + +static int insert_temp_dev_item(int fd, struct extent_buffer *buf, + struct btrfs_mkfs_config *cfg, + int *slot, u32 *itemoff) +{ + struct btrfs_disk_key disk_key; + struct btrfs_dev_item *dev_item; + char super_buf[BTRFS_SUPER_INFO_SIZE]; + unsigned char dev_uuid[BTRFS_UUID_SIZE]; + unsigned char fsid[BTRFS_FSID_SIZE]; + struct btrfs_super_block *super = (struct btrfs_super_block *)super_buf; + int ret; + + ret = pread(fd, super_buf, BTRFS_SUPER_INFO_SIZE, cfg->super_bytenr); + if (ret < BTRFS_SUPER_INFO_SIZE) { + ret = (ret < 0 ? -errno : -EIO); + goto out; + } + + btrfs_set_header_nritems(buf, *slot + 1); + (*itemoff) -= sizeof(*dev_item); + /* setup device item 1, 0 is for replace case */ + btrfs_set_disk_key_type(&disk_key, BTRFS_DEV_ITEM_KEY); + btrfs_set_disk_key_objectid(&disk_key, BTRFS_DEV_ITEMS_OBJECTID); + btrfs_set_disk_key_offset(&disk_key, 1); + btrfs_set_item_key(buf, &disk_key, *slot); + btrfs_set_item_offset(buf, btrfs_item_nr(*slot), *itemoff); + btrfs_set_item_size(buf, btrfs_item_nr(*slot), sizeof(*dev_item)); + + dev_item = btrfs_item_ptr(buf, *slot, struct btrfs_dev_item); + /* Generate device uuid */ + uuid_generate(dev_uuid); + write_extent_buffer(buf, dev_uuid, + (unsigned long)btrfs_device_uuid(dev_item), + BTRFS_UUID_SIZE); + uuid_parse(cfg->fs_uuid, fsid); + write_extent_buffer(buf, fsid, + (unsigned long)btrfs_device_fsid(dev_item), + BTRFS_FSID_SIZE); + btrfs_set_device_id(buf, dev_item, 1); + btrfs_set_device_generation(buf, dev_item, 0); + btrfs_set_device_total_bytes(buf, dev_item, cfg->num_bytes); + /* + * The number must match the initial SYSTEM and META chunk size + */ + btrfs_set_device_bytes_used(buf, dev_item, + BTRFS_MKFS_SYSTEM_GROUP_SIZE + + BTRFS_CONVERT_META_GROUP_SIZE); + btrfs_set_device_io_align(buf, dev_item, cfg->sectorsize); + btrfs_set_device_io_width(buf, dev_item, cfg->sectorsize); + btrfs_set_device_sector_size(buf, dev_item, cfg->sectorsize); + btrfs_set_device_type(buf, dev_item, 0); + + /* Super dev_item is not complete, copy the complete one to sb */ + read_extent_buffer(buf, &super->dev_item, (unsigned long)dev_item, + sizeof(*dev_item)); + ret = write_temp_super(fd, super, cfg->super_bytenr); + (*slot)++; +out: + return ret; +} + +static int insert_temp_chunk_item(int fd, struct extent_buffer *buf, + struct btrfs_mkfs_config *cfg, + int *slot, u32 *itemoff, u64 start, u64 len, + u64 type) +{ + struct btrfs_chunk *chunk; + struct btrfs_disk_key disk_key; + char super_buf[BTRFS_SUPER_INFO_SIZE]; + struct btrfs_super_block *sb = (struct btrfs_super_block *)super_buf; + int ret = 0; + + ret = pread(fd, super_buf, BTRFS_SUPER_INFO_SIZE, + cfg->super_bytenr); + if (ret < BTRFS_SUPER_INFO_SIZE) { + ret = (ret < 0 ? ret : -EIO); + return ret; + } + + btrfs_set_header_nritems(buf, *slot + 1); + (*itemoff) -= btrfs_chunk_item_size(1); + btrfs_set_disk_key_type(&disk_key, BTRFS_CHUNK_ITEM_KEY); + btrfs_set_disk_key_objectid(&disk_key, BTRFS_FIRST_CHUNK_TREE_OBJECTID); + btrfs_set_disk_key_offset(&disk_key, start); + btrfs_set_item_key(buf, &disk_key, *slot); + btrfs_set_item_offset(buf, btrfs_item_nr(*slot), *itemoff); + btrfs_set_item_size(buf, btrfs_item_nr(*slot), + btrfs_chunk_item_size(1)); + + chunk = btrfs_item_ptr(buf, *slot, struct btrfs_chunk); + btrfs_set_chunk_length(buf, chunk, len); + btrfs_set_chunk_owner(buf, chunk, BTRFS_EXTENT_TREE_OBJECTID); + btrfs_set_chunk_stripe_len(buf, chunk, 64 * 1024); + btrfs_set_chunk_type(buf, chunk, type); + btrfs_set_chunk_io_align(buf, chunk, cfg->sectorsize); + btrfs_set_chunk_io_width(buf, chunk, cfg->sectorsize); + btrfs_set_chunk_sector_size(buf, chunk, cfg->sectorsize); + btrfs_set_chunk_num_stripes(buf, chunk, 1); + /* TODO: Support DUP profile for system chunk */ + btrfs_set_stripe_devid_nr(buf, chunk, 0, 1); + /* We are doing 1:1 mapping, so start is its dev offset */ + btrfs_set_stripe_offset_nr(buf, chunk, 0, start); + write_extent_buffer(buf, &sb->dev_item.uuid, + (unsigned long)btrfs_stripe_dev_uuid_nr(chunk, 0), + BTRFS_UUID_SIZE); + (*slot)++; + + /* + * If it's system chunk, also copy it to super block. + */ + if (type & BTRFS_BLOCK_GROUP_SYSTEM) { + char *cur; + + cur = (char *)sb->sys_chunk_array + sb->sys_chunk_array_size; + memcpy(cur, &disk_key, sizeof(disk_key)); + cur += sizeof(disk_key); + read_extent_buffer(buf, cur, (unsigned long int)chunk, + btrfs_chunk_item_size(1)); + sb->sys_chunk_array_size += btrfs_chunk_item_size(1) + + sizeof(disk_key); + + ret = write_temp_super(fd, sb, cfg->super_bytenr); + } + return ret; +} + +static int setup_temp_chunk_tree(int fd, struct btrfs_mkfs_config *cfg, + u64 sys_chunk_start, u64 meta_chunk_start, + u64 chunk_bytenr) +{ + struct extent_buffer *buf = NULL; + u32 itemoff = __BTRFS_LEAF_DATA_SIZE(cfg->nodesize); + int slot = 0; + int ret; + + /* Must ensure SYS chunk starts before META chunk */ + BUG_ON(meta_chunk_start < sys_chunk_start); + buf = malloc(sizeof(*buf) + cfg->nodesize); + if (!buf) + return -ENOMEM; + ret = setup_temp_extent_buffer(buf, cfg, chunk_bytenr, + BTRFS_CHUNK_TREE_OBJECTID); + if (ret < 0) + goto out; + + ret = insert_temp_dev_item(fd, buf, cfg, &slot, &itemoff); + if (ret < 0) + goto out; + ret = insert_temp_chunk_item(fd, buf, cfg, &slot, &itemoff, + sys_chunk_start, + BTRFS_MKFS_SYSTEM_GROUP_SIZE, + BTRFS_BLOCK_GROUP_SYSTEM); + if (ret < 0) + goto out; + ret = insert_temp_chunk_item(fd, buf, cfg, &slot, &itemoff, + meta_chunk_start, + BTRFS_CONVERT_META_GROUP_SIZE, + BTRFS_BLOCK_GROUP_METADATA); + if (ret < 0) + goto out; + ret = write_temp_extent_buffer(fd, buf, chunk_bytenr); + +out: + free(buf); + return ret; +} + +static void insert_temp_dev_extent(struct extent_buffer *buf, + int *slot, u32 *itemoff, u64 start, u64 len) +{ + struct btrfs_dev_extent *dev_extent; + struct btrfs_disk_key disk_key; + + btrfs_set_header_nritems(buf, *slot + 1); + (*itemoff) -= sizeof(*dev_extent); + btrfs_set_disk_key_type(&disk_key, BTRFS_DEV_EXTENT_KEY); + btrfs_set_disk_key_objectid(&disk_key, 1); + btrfs_set_disk_key_offset(&disk_key, start); + btrfs_set_item_key(buf, &disk_key, *slot); + btrfs_set_item_offset(buf, btrfs_item_nr(*slot), *itemoff); + btrfs_set_item_size(buf, btrfs_item_nr(*slot), sizeof(*dev_extent)); + + dev_extent = btrfs_item_ptr(buf, *slot, struct btrfs_dev_extent); + btrfs_set_dev_extent_chunk_objectid(buf, dev_extent, + BTRFS_FIRST_CHUNK_TREE_OBJECTID); + btrfs_set_dev_extent_length(buf, dev_extent, len); + btrfs_set_dev_extent_chunk_offset(buf, dev_extent, start); + btrfs_set_dev_extent_chunk_tree(buf, dev_extent, + BTRFS_CHUNK_TREE_OBJECTID); + (*slot)++; +} + +static int setup_temp_dev_tree(int fd, struct btrfs_mkfs_config *cfg, + u64 sys_chunk_start, u64 meta_chunk_start, + u64 dev_bytenr) +{ + struct extent_buffer *buf = NULL; + u32 itemoff = __BTRFS_LEAF_DATA_SIZE(cfg->nodesize); + int slot = 0; + int ret; + + /* Must ensure SYS chunk starts before META chunk */ + BUG_ON(meta_chunk_start < sys_chunk_start); + buf = malloc(sizeof(*buf) + cfg->nodesize); + if (!buf) + return -ENOMEM; + ret = setup_temp_extent_buffer(buf, cfg, dev_bytenr, + BTRFS_DEV_TREE_OBJECTID); + if (ret < 0) + goto out; + insert_temp_dev_extent(buf, &slot, &itemoff, sys_chunk_start, + BTRFS_MKFS_SYSTEM_GROUP_SIZE); + insert_temp_dev_extent(buf, &slot, &itemoff, meta_chunk_start, + BTRFS_CONVERT_META_GROUP_SIZE); + ret = write_temp_extent_buffer(fd, buf, dev_bytenr); +out: + free(buf); + return ret; +} + +static int setup_temp_fs_tree(int fd, struct btrfs_mkfs_config *cfg, + u64 fs_bytenr) +{ + struct extent_buffer *buf = NULL; + int ret; + + buf = malloc(sizeof(*buf) + cfg->nodesize); + if (!buf) + return -ENOMEM; + ret = setup_temp_extent_buffer(buf, cfg, fs_bytenr, + BTRFS_FS_TREE_OBJECTID); + if (ret < 0) + goto out; + /* + * Temporary fs tree is completely empty. + */ + ret = write_temp_extent_buffer(fd, buf, fs_bytenr); +out: + free(buf); + return ret; +} + +static int setup_temp_csum_tree(int fd, struct btrfs_mkfs_config *cfg, + u64 csum_bytenr) +{ + struct extent_buffer *buf = NULL; + int ret; + + buf = malloc(sizeof(*buf) + cfg->nodesize); + if (!buf) + return -ENOMEM; + ret = setup_temp_extent_buffer(buf, cfg, csum_bytenr, + BTRFS_CSUM_TREE_OBJECTID); + if (ret < 0) + goto out; + /* + * Temporary csum tree is completely empty. + */ + ret = write_temp_extent_buffer(fd, buf, csum_bytenr); +out: + free(buf); + return ret; +} + +/* + * Insert one temporary extent item. + * + * NOTE: if skinny_metadata is not enabled, this function must be called + * after all other trees are initialized. + * Or fs without skinny-metadata will be screwed up. + */ +static int insert_temp_extent_item(int fd, struct extent_buffer *buf, + struct btrfs_mkfs_config *cfg, + int *slot, u32 *itemoff, u64 bytenr, + u64 ref_root) +{ + struct extent_buffer *tmp; + struct btrfs_extent_item *ei; + struct btrfs_extent_inline_ref *iref; + struct btrfs_disk_key disk_key; + struct btrfs_disk_key tree_info_key; + struct btrfs_tree_block_info *info; + int itemsize; + int skinny_metadata = cfg->features & + BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA; + int ret; + + if (skinny_metadata) + itemsize = sizeof(*ei) + sizeof(*iref); + else + itemsize = sizeof(*ei) + sizeof(*iref) + + sizeof(struct btrfs_tree_block_info); + + btrfs_set_header_nritems(buf, *slot + 1); + *(itemoff) -= itemsize; + + if (skinny_metadata) { + btrfs_set_disk_key_type(&disk_key, BTRFS_METADATA_ITEM_KEY); + btrfs_set_disk_key_offset(&disk_key, 0); + } else { + btrfs_set_disk_key_type(&disk_key, BTRFS_EXTENT_ITEM_KEY); + btrfs_set_disk_key_offset(&disk_key, cfg->nodesize); + } + btrfs_set_disk_key_objectid(&disk_key, bytenr); + + btrfs_set_item_key(buf, &disk_key, *slot); + btrfs_set_item_offset(buf, btrfs_item_nr(*slot), *itemoff); + btrfs_set_item_size(buf, btrfs_item_nr(*slot), itemsize); + + ei = btrfs_item_ptr(buf, *slot, struct btrfs_extent_item); + btrfs_set_extent_refs(buf, ei, 1); + btrfs_set_extent_generation(buf, ei, 1); + btrfs_set_extent_flags(buf, ei, BTRFS_EXTENT_FLAG_TREE_BLOCK); + + if (skinny_metadata) { + iref = (struct btrfs_extent_inline_ref *)(ei + 1); + } else { + info = (struct btrfs_tree_block_info *)(ei + 1); + iref = (struct btrfs_extent_inline_ref *)(info + 1); + } + btrfs_set_extent_inline_ref_type(buf, iref, + BTRFS_TREE_BLOCK_REF_KEY); + btrfs_set_extent_inline_ref_offset(buf, iref, ref_root); + + (*slot)++; + if (skinny_metadata) + return 0; + + /* + * Lastly, check the tree block key by read the tree block + * Since we do 1:1 mapping for convert case, we can directly + * read the bytenr from disk + */ + tmp = malloc(sizeof(*tmp) + cfg->nodesize); + if (!tmp) + return -ENOMEM; + ret = setup_temp_extent_buffer(tmp, cfg, bytenr, ref_root); + if (ret < 0) + goto out; + ret = pread(fd, tmp->data, cfg->nodesize, bytenr); + if (ret < cfg->nodesize) { + ret = (ret < 0 ? -errno : -EIO); + goto out; + } + if (btrfs_header_nritems(tmp) == 0) { + btrfs_set_disk_key_type(&tree_info_key, 0); + btrfs_set_disk_key_objectid(&tree_info_key, 0); + btrfs_set_disk_key_offset(&tree_info_key, 0); + } else { + btrfs_item_key(tmp, &tree_info_key, 0); + } + btrfs_set_tree_block_key(buf, info, &tree_info_key); + +out: + free(tmp); + return ret; +} + +static void insert_temp_block_group(struct extent_buffer *buf, + struct btrfs_mkfs_config *cfg, + int *slot, u32 *itemoff, + u64 bytenr, u64 len, u64 used, u64 flag) +{ + struct btrfs_block_group_item bgi; + struct btrfs_disk_key disk_key; + + btrfs_set_header_nritems(buf, *slot + 1); + (*itemoff) -= sizeof(bgi); + btrfs_set_disk_key_type(&disk_key, BTRFS_BLOCK_GROUP_ITEM_KEY); + btrfs_set_disk_key_objectid(&disk_key, bytenr); + btrfs_set_disk_key_offset(&disk_key, len); + btrfs_set_item_key(buf, &disk_key, *slot); + btrfs_set_item_offset(buf, btrfs_item_nr(*slot), *itemoff); + btrfs_set_item_size(buf, btrfs_item_nr(*slot), sizeof(bgi)); + + btrfs_set_block_group_flags(&bgi, flag); + btrfs_set_block_group_used(&bgi, used); + btrfs_set_block_group_chunk_objectid(&bgi, + BTRFS_FIRST_CHUNK_TREE_OBJECTID); + write_extent_buffer(buf, &bgi, btrfs_item_ptr_offset(buf, *slot), + sizeof(bgi)); + (*slot)++; +} + +static int setup_temp_extent_tree(int fd, struct btrfs_mkfs_config *cfg, + u64 chunk_bytenr, u64 root_bytenr, + u64 extent_bytenr, u64 dev_bytenr, + u64 fs_bytenr, u64 csum_bytenr) +{ + struct extent_buffer *buf = NULL; + u32 itemoff = __BTRFS_LEAF_DATA_SIZE(cfg->nodesize); + int slot = 0; + int ret; + + /* + * We must ensure provided bytenr are in ascending order, + * or extent tree key order will be broken. + */ + BUG_ON(!(chunk_bytenr < root_bytenr && root_bytenr < extent_bytenr && + extent_bytenr < dev_bytenr && dev_bytenr < fs_bytenr && + fs_bytenr < csum_bytenr)); + buf = malloc(sizeof(*buf) + cfg->nodesize); + if (!buf) + return -ENOMEM; + + ret = setup_temp_extent_buffer(buf, cfg, extent_bytenr, + BTRFS_EXTENT_TREE_OBJECTID); + if (ret < 0) + goto out; + + ret = insert_temp_extent_item(fd, buf, cfg, &slot, &itemoff, + chunk_bytenr, BTRFS_CHUNK_TREE_OBJECTID); + if (ret < 0) + goto out; + + insert_temp_block_group(buf, cfg, &slot, &itemoff, chunk_bytenr, + BTRFS_MKFS_SYSTEM_GROUP_SIZE, cfg->nodesize, + BTRFS_BLOCK_GROUP_SYSTEM); + + ret = insert_temp_extent_item(fd, buf, cfg, &slot, &itemoff, + root_bytenr, BTRFS_ROOT_TREE_OBJECTID); + if (ret < 0) + goto out; + + /* 5 tree block used, root, extent, dev, fs and csum*/ + insert_temp_block_group(buf, cfg, &slot, &itemoff, root_bytenr, + BTRFS_CONVERT_META_GROUP_SIZE, cfg->nodesize * 5, + BTRFS_BLOCK_GROUP_METADATA); + + ret = insert_temp_extent_item(fd, buf, cfg, &slot, &itemoff, + extent_bytenr, BTRFS_EXTENT_TREE_OBJECTID); + if (ret < 0) + goto out; + ret = insert_temp_extent_item(fd, buf, cfg, &slot, &itemoff, + dev_bytenr, BTRFS_DEV_TREE_OBJECTID); + if (ret < 0) + goto out; + ret = insert_temp_extent_item(fd, buf, cfg, &slot, &itemoff, + fs_bytenr, BTRFS_FS_TREE_OBJECTID); + if (ret < 0) + goto out; + ret = insert_temp_extent_item(fd, buf, cfg, &slot, &itemoff, + csum_bytenr, BTRFS_CSUM_TREE_OBJECTID); + if (ret < 0) + goto out; + + ret = write_temp_extent_buffer(fd, buf, extent_bytenr); +out: + free(buf); + return ret; +} + +/* + * Improved version of make_btrfs(). + * + * This one will + * 1) Do chunk allocation to avoid used data + * And after this function, extent type matches chunk type + * 2) Better structured code + * No super long hand written codes to initialized all tree blocks + * Split into small blocks and reuse codes. + * TODO: Reuse tree operation facilities by introducing new flags + */ +static int make_convert_btrfs(int fd, struct btrfs_mkfs_config *cfg, + struct btrfs_convert_context *cctx) +{ + struct cache_tree *free = &cctx->free; + struct cache_tree *used = &cctx->used; + u64 sys_chunk_start; + u64 meta_chunk_start; + /* chunk tree bytenr, in system chunk */ + u64 chunk_bytenr; + /* metadata trees bytenr, in metadata chunk */ + u64 root_bytenr; + u64 extent_bytenr; + u64 dev_bytenr; + u64 fs_bytenr; + u64 csum_bytenr; + int ret; + + /* Shouldn't happen */ + BUG_ON(cache_tree_empty(used)); + + /* + * reserve space for temporary superblock first + * Here we allocate a little larger space, to keep later + * free space will be STRIPE_LEN aligned + */ + ret = reserve_free_space(free, BTRFS_STRIPE_LEN, + &cfg->super_bytenr); + if (ret < 0) + goto out; + + /* + * Then reserve system chunk space + * TODO: Change system group size depending on cctx->total_bytes. + * If using current 4M, it can only handle less than one TB for + * worst case and then run out of sys space. + */ + ret = reserve_free_space(free, BTRFS_MKFS_SYSTEM_GROUP_SIZE, + &sys_chunk_start); + if (ret < 0) + goto out; + ret = reserve_free_space(free, BTRFS_CONVERT_META_GROUP_SIZE, + &meta_chunk_start); + if (ret < 0) + goto out; + + /* + * Allocated meta/sys chunks will be mapped 1:1 with device offset. + * + * Inside the allocated metadata chunk, the layout will be: + * | offset | contents | + * ------------------------------------- + * | +0 | tree root | + * | +nodesize | extent root | + * | +nodesize * 2 | device root | + * | +nodesize * 3 | fs tree | + * | +nodesize * 4 | csum tree | + * ------------------------------------- + * Inside the allocated system chunk, the layout will be: + * | offset | contents | + * ------------------------------------- + * | +0 | chunk root | + * ------------------------------------- + */ + chunk_bytenr = sys_chunk_start; + root_bytenr = meta_chunk_start; + extent_bytenr = meta_chunk_start + cfg->nodesize; + dev_bytenr = meta_chunk_start + cfg->nodesize * 2; + fs_bytenr = meta_chunk_start + cfg->nodesize * 3; + csum_bytenr = meta_chunk_start + cfg->nodesize * 4; + + ret = setup_temp_super(fd, cfg, root_bytenr, chunk_bytenr); + if (ret < 0) + goto out; + + ret = setup_temp_root_tree(fd, cfg, root_bytenr, extent_bytenr, + dev_bytenr, fs_bytenr, csum_bytenr); + if (ret < 0) + goto out; + ret = setup_temp_chunk_tree(fd, cfg, sys_chunk_start, meta_chunk_start, + chunk_bytenr); + if (ret < 0) + goto out; + ret = setup_temp_dev_tree(fd, cfg, sys_chunk_start, meta_chunk_start, + dev_bytenr); + if (ret < 0) + goto out; + ret = setup_temp_fs_tree(fd, cfg, fs_bytenr); + if (ret < 0) + goto out; + ret = setup_temp_csum_tree(fd, cfg, csum_bytenr); + if (ret < 0) + goto out; + /* + * Setup extent tree last, since it may need to read tree block key + * for non-skinny metadata case. + */ + ret = setup_temp_extent_tree(fd, cfg, chunk_bytenr, root_bytenr, + extent_bytenr, dev_bytenr, fs_bytenr, + csum_bytenr); +out: + return ret; +} + +/* + * @fs_uuid - if NULL, generates a UUID, returns back the new filesystem UUID + */ +int make_btrfs(int fd, struct btrfs_mkfs_config *cfg, + struct btrfs_convert_context *cctx) +{ + struct btrfs_super_block super; + struct extent_buffer *buf; + struct btrfs_root_item root_item; + struct btrfs_disk_key disk_key; + struct btrfs_extent_item *extent_item; + struct btrfs_inode_item *inode_item; + struct btrfs_chunk *chunk; + struct btrfs_dev_item *dev_item; + struct btrfs_dev_extent *dev_extent; + u8 chunk_tree_uuid[BTRFS_UUID_SIZE]; + u8 *ptr; + int i; + int ret; + u32 itemoff; + u32 nritems = 0; + u64 first_free; + u64 ref_root; + u32 array_size; + u32 item_size; + int skinny_metadata = !!(cfg->features & + BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA); + u64 num_bytes; + + if (cctx) + return make_convert_btrfs(fd, cfg, cctx); + buf = malloc(sizeof(*buf) + max(cfg->sectorsize, cfg->nodesize)); + if (!buf) + return -ENOMEM; + + first_free = BTRFS_SUPER_INFO_OFFSET + cfg->sectorsize * 2 - 1; + first_free &= ~((u64)cfg->sectorsize - 1); + + memset(&super, 0, sizeof(super)); + + num_bytes = (cfg->num_bytes / cfg->sectorsize) * cfg->sectorsize; + if (cfg->fs_uuid && *cfg->fs_uuid) { + if (uuid_parse(cfg->fs_uuid, super.fsid) != 0) { + error("cannot not parse UUID: %s", cfg->fs_uuid); + ret = -EINVAL; + goto out; + } + if (!test_uuid_unique(cfg->fs_uuid)) { + error("non-unique UUID: %s", cfg->fs_uuid); + ret = -EBUSY; + goto out; + } + } else { + uuid_generate(super.fsid); + if (cfg->fs_uuid) + uuid_unparse(super.fsid, cfg->fs_uuid); + } + uuid_generate(super.dev_item.uuid); + uuid_generate(chunk_tree_uuid); + + btrfs_set_super_bytenr(&super, cfg->blocks[0]); + btrfs_set_super_num_devices(&super, 1); + btrfs_set_super_magic(&super, BTRFS_MAGIC); + btrfs_set_super_generation(&super, 1); + btrfs_set_super_root(&super, cfg->blocks[1]); + btrfs_set_super_chunk_root(&super, cfg->blocks[3]); + btrfs_set_super_total_bytes(&super, num_bytes); + btrfs_set_super_bytes_used(&super, 6 * cfg->nodesize); + btrfs_set_super_sectorsize(&super, cfg->sectorsize); + btrfs_set_super_leafsize(&super, cfg->nodesize); + btrfs_set_super_nodesize(&super, cfg->nodesize); + btrfs_set_super_stripesize(&super, cfg->stripesize); + btrfs_set_super_csum_type(&super, BTRFS_CSUM_TYPE_CRC32); + btrfs_set_super_chunk_root_generation(&super, 1); + btrfs_set_super_cache_generation(&super, -1); + btrfs_set_super_incompat_flags(&super, cfg->features); + if (cfg->label) + __strncpy_null(super.label, cfg->label, BTRFS_LABEL_SIZE - 1); + + /* create the tree of root objects */ + memset(buf->data, 0, cfg->nodesize); + buf->len = cfg->nodesize; + btrfs_set_header_bytenr(buf, cfg->blocks[1]); + btrfs_set_header_nritems(buf, 4); + btrfs_set_header_generation(buf, 1); + btrfs_set_header_backref_rev(buf, BTRFS_MIXED_BACKREF_REV); + btrfs_set_header_owner(buf, BTRFS_ROOT_TREE_OBJECTID); + write_extent_buffer(buf, super.fsid, btrfs_header_fsid(), + BTRFS_FSID_SIZE); + + write_extent_buffer(buf, chunk_tree_uuid, + btrfs_header_chunk_tree_uuid(buf), + BTRFS_UUID_SIZE); + + /* create the items for the root tree */ + memset(&root_item, 0, sizeof(root_item)); + inode_item = &root_item.inode; + btrfs_set_stack_inode_generation(inode_item, 1); + btrfs_set_stack_inode_size(inode_item, 3); + btrfs_set_stack_inode_nlink(inode_item, 1); + btrfs_set_stack_inode_nbytes(inode_item, cfg->nodesize); + btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755); + btrfs_set_root_refs(&root_item, 1); + btrfs_set_root_used(&root_item, cfg->nodesize); + btrfs_set_root_generation(&root_item, 1); + + memset(&disk_key, 0, sizeof(disk_key)); + btrfs_set_disk_key_type(&disk_key, BTRFS_ROOT_ITEM_KEY); + btrfs_set_disk_key_offset(&disk_key, 0); + nritems = 0; + + itemoff = __BTRFS_LEAF_DATA_SIZE(cfg->nodesize) - sizeof(root_item); + btrfs_set_root_bytenr(&root_item, cfg->blocks[2]); + btrfs_set_disk_key_objectid(&disk_key, BTRFS_EXTENT_TREE_OBJECTID); + btrfs_set_item_key(buf, &disk_key, nritems); + btrfs_set_item_offset(buf, btrfs_item_nr(nritems), itemoff); + btrfs_set_item_size(buf, btrfs_item_nr(nritems), + sizeof(root_item)); + write_extent_buffer(buf, &root_item, btrfs_item_ptr_offset(buf, + nritems), sizeof(root_item)); + nritems++; + + itemoff = itemoff - sizeof(root_item); + btrfs_set_root_bytenr(&root_item, cfg->blocks[4]); + btrfs_set_disk_key_objectid(&disk_key, BTRFS_DEV_TREE_OBJECTID); + btrfs_set_item_key(buf, &disk_key, nritems); + btrfs_set_item_offset(buf, btrfs_item_nr(nritems), itemoff); + btrfs_set_item_size(buf, btrfs_item_nr(nritems), + sizeof(root_item)); + write_extent_buffer(buf, &root_item, + btrfs_item_ptr_offset(buf, nritems), + sizeof(root_item)); + nritems++; + + itemoff = itemoff - sizeof(root_item); + btrfs_set_root_bytenr(&root_item, cfg->blocks[5]); + btrfs_set_disk_key_objectid(&disk_key, BTRFS_FS_TREE_OBJECTID); + btrfs_set_item_key(buf, &disk_key, nritems); + btrfs_set_item_offset(buf, btrfs_item_nr(nritems), itemoff); + btrfs_set_item_size(buf, btrfs_item_nr(nritems), + sizeof(root_item)); + write_extent_buffer(buf, &root_item, + btrfs_item_ptr_offset(buf, nritems), + sizeof(root_item)); + nritems++; + + itemoff = itemoff - sizeof(root_item); + btrfs_set_root_bytenr(&root_item, cfg->blocks[6]); + btrfs_set_disk_key_objectid(&disk_key, BTRFS_CSUM_TREE_OBJECTID); + btrfs_set_item_key(buf, &disk_key, nritems); + btrfs_set_item_offset(buf, btrfs_item_nr(nritems), itemoff); + btrfs_set_item_size(buf, btrfs_item_nr(nritems), + sizeof(root_item)); + write_extent_buffer(buf, &root_item, + btrfs_item_ptr_offset(buf, nritems), + sizeof(root_item)); + nritems++; + + + csum_tree_block_size(buf, BTRFS_CRC32_SIZE, 0); + ret = pwrite(fd, buf->data, cfg->nodesize, cfg->blocks[1]); + if (ret != cfg->nodesize) { + ret = (ret < 0 ? -errno : -EIO); + goto out; + } + + /* create the items for the extent tree */ + memset(buf->data + sizeof(struct btrfs_header), 0, + cfg->nodesize - sizeof(struct btrfs_header)); + nritems = 0; + itemoff = __BTRFS_LEAF_DATA_SIZE(cfg->nodesize); + for (i = 1; i < 7; i++) { + item_size = sizeof(struct btrfs_extent_item); + if (!skinny_metadata) + item_size += sizeof(struct btrfs_tree_block_info); + + BUG_ON(cfg->blocks[i] < first_free); + BUG_ON(cfg->blocks[i] < cfg->blocks[i - 1]); + + /* create extent item */ + itemoff -= item_size; + btrfs_set_disk_key_objectid(&disk_key, cfg->blocks[i]); + if (skinny_metadata) { + btrfs_set_disk_key_type(&disk_key, + BTRFS_METADATA_ITEM_KEY); + btrfs_set_disk_key_offset(&disk_key, 0); + } else { + btrfs_set_disk_key_type(&disk_key, + BTRFS_EXTENT_ITEM_KEY); + btrfs_set_disk_key_offset(&disk_key, cfg->nodesize); + } + btrfs_set_item_key(buf, &disk_key, nritems); + btrfs_set_item_offset(buf, btrfs_item_nr(nritems), + itemoff); + btrfs_set_item_size(buf, btrfs_item_nr(nritems), + item_size); + extent_item = btrfs_item_ptr(buf, nritems, + struct btrfs_extent_item); + btrfs_set_extent_refs(buf, extent_item, 1); + btrfs_set_extent_generation(buf, extent_item, 1); + btrfs_set_extent_flags(buf, extent_item, + BTRFS_EXTENT_FLAG_TREE_BLOCK); + nritems++; + + /* create extent ref */ + ref_root = reference_root_table[i]; + btrfs_set_disk_key_objectid(&disk_key, cfg->blocks[i]); + btrfs_set_disk_key_offset(&disk_key, ref_root); + btrfs_set_disk_key_type(&disk_key, BTRFS_TREE_BLOCK_REF_KEY); + btrfs_set_item_key(buf, &disk_key, nritems); + btrfs_set_item_offset(buf, btrfs_item_nr(nritems), + itemoff); + btrfs_set_item_size(buf, btrfs_item_nr(nritems), 0); + nritems++; + } + btrfs_set_header_bytenr(buf, cfg->blocks[2]); + btrfs_set_header_owner(buf, BTRFS_EXTENT_TREE_OBJECTID); + btrfs_set_header_nritems(buf, nritems); + csum_tree_block_size(buf, BTRFS_CRC32_SIZE, 0); + ret = pwrite(fd, buf->data, cfg->nodesize, cfg->blocks[2]); + if (ret != cfg->nodesize) { + ret = (ret < 0 ? -errno : -EIO); + goto out; + } + + /* create the chunk tree */ + memset(buf->data + sizeof(struct btrfs_header), 0, + cfg->nodesize - sizeof(struct btrfs_header)); + nritems = 0; + item_size = sizeof(*dev_item); + itemoff = __BTRFS_LEAF_DATA_SIZE(cfg->nodesize) - item_size; + + /* first device 1 (there is no device 0) */ + btrfs_set_disk_key_objectid(&disk_key, BTRFS_DEV_ITEMS_OBJECTID); + btrfs_set_disk_key_offset(&disk_key, 1); + btrfs_set_disk_key_type(&disk_key, BTRFS_DEV_ITEM_KEY); + btrfs_set_item_key(buf, &disk_key, nritems); + btrfs_set_item_offset(buf, btrfs_item_nr(nritems), itemoff); + btrfs_set_item_size(buf, btrfs_item_nr(nritems), item_size); + + dev_item = btrfs_item_ptr(buf, nritems, struct btrfs_dev_item); + btrfs_set_device_id(buf, dev_item, 1); + btrfs_set_device_generation(buf, dev_item, 0); + btrfs_set_device_total_bytes(buf, dev_item, num_bytes); + btrfs_set_device_bytes_used(buf, dev_item, + BTRFS_MKFS_SYSTEM_GROUP_SIZE); + btrfs_set_device_io_align(buf, dev_item, cfg->sectorsize); + btrfs_set_device_io_width(buf, dev_item, cfg->sectorsize); + btrfs_set_device_sector_size(buf, dev_item, cfg->sectorsize); + btrfs_set_device_type(buf, dev_item, 0); + + write_extent_buffer(buf, super.dev_item.uuid, + (unsigned long)btrfs_device_uuid(dev_item), + BTRFS_UUID_SIZE); + write_extent_buffer(buf, super.fsid, + (unsigned long)btrfs_device_fsid(dev_item), + BTRFS_UUID_SIZE); + read_extent_buffer(buf, &super.dev_item, (unsigned long)dev_item, + sizeof(*dev_item)); + + nritems++; + item_size = btrfs_chunk_item_size(1); + itemoff = itemoff - item_size; + + /* then we have chunk 0 */ + btrfs_set_disk_key_objectid(&disk_key, BTRFS_FIRST_CHUNK_TREE_OBJECTID); + btrfs_set_disk_key_offset(&disk_key, 0); + btrfs_set_disk_key_type(&disk_key, BTRFS_CHUNK_ITEM_KEY); + btrfs_set_item_key(buf, &disk_key, nritems); + btrfs_set_item_offset(buf, btrfs_item_nr(nritems), itemoff); + btrfs_set_item_size(buf, btrfs_item_nr(nritems), item_size); + + chunk = btrfs_item_ptr(buf, nritems, struct btrfs_chunk); + btrfs_set_chunk_length(buf, chunk, BTRFS_MKFS_SYSTEM_GROUP_SIZE); + btrfs_set_chunk_owner(buf, chunk, BTRFS_EXTENT_TREE_OBJECTID); + btrfs_set_chunk_stripe_len(buf, chunk, 64 * 1024); + btrfs_set_chunk_type(buf, chunk, BTRFS_BLOCK_GROUP_SYSTEM); + btrfs_set_chunk_io_align(buf, chunk, cfg->sectorsize); + btrfs_set_chunk_io_width(buf, chunk, cfg->sectorsize); + btrfs_set_chunk_sector_size(buf, chunk, cfg->sectorsize); + btrfs_set_chunk_num_stripes(buf, chunk, 1); + btrfs_set_stripe_devid_nr(buf, chunk, 0, 1); + btrfs_set_stripe_offset_nr(buf, chunk, 0, 0); + nritems++; + + write_extent_buffer(buf, super.dev_item.uuid, + (unsigned long)btrfs_stripe_dev_uuid(&chunk->stripe), + BTRFS_UUID_SIZE); + + /* copy the key for the chunk to the system array */ + ptr = super.sys_chunk_array; + array_size = sizeof(disk_key); + + memcpy(ptr, &disk_key, sizeof(disk_key)); + ptr += sizeof(disk_key); + + /* copy the chunk to the system array */ + read_extent_buffer(buf, ptr, (unsigned long)chunk, item_size); + array_size += item_size; + ptr += item_size; + btrfs_set_super_sys_array_size(&super, array_size); + + btrfs_set_header_bytenr(buf, cfg->blocks[3]); + btrfs_set_header_owner(buf, BTRFS_CHUNK_TREE_OBJECTID); + btrfs_set_header_nritems(buf, nritems); + csum_tree_block_size(buf, BTRFS_CRC32_SIZE, 0); + ret = pwrite(fd, buf->data, cfg->nodesize, cfg->blocks[3]); + if (ret != cfg->nodesize) { + ret = (ret < 0 ? -errno : -EIO); + goto out; + } + + /* create the device tree */ + memset(buf->data + sizeof(struct btrfs_header), 0, + cfg->nodesize - sizeof(struct btrfs_header)); + nritems = 0; + itemoff = __BTRFS_LEAF_DATA_SIZE(cfg->nodesize) - + sizeof(struct btrfs_dev_extent); + + btrfs_set_disk_key_objectid(&disk_key, 1); + btrfs_set_disk_key_offset(&disk_key, 0); + btrfs_set_disk_key_type(&disk_key, BTRFS_DEV_EXTENT_KEY); + btrfs_set_item_key(buf, &disk_key, nritems); + btrfs_set_item_offset(buf, btrfs_item_nr(nritems), itemoff); + btrfs_set_item_size(buf, btrfs_item_nr(nritems), + sizeof(struct btrfs_dev_extent)); + dev_extent = btrfs_item_ptr(buf, nritems, struct btrfs_dev_extent); + btrfs_set_dev_extent_chunk_tree(buf, dev_extent, + BTRFS_CHUNK_TREE_OBJECTID); + btrfs_set_dev_extent_chunk_objectid(buf, dev_extent, + BTRFS_FIRST_CHUNK_TREE_OBJECTID); + btrfs_set_dev_extent_chunk_offset(buf, dev_extent, 0); + + write_extent_buffer(buf, chunk_tree_uuid, + (unsigned long)btrfs_dev_extent_chunk_tree_uuid(dev_extent), + BTRFS_UUID_SIZE); + + btrfs_set_dev_extent_length(buf, dev_extent, + BTRFS_MKFS_SYSTEM_GROUP_SIZE); + nritems++; + + btrfs_set_header_bytenr(buf, cfg->blocks[4]); + btrfs_set_header_owner(buf, BTRFS_DEV_TREE_OBJECTID); + btrfs_set_header_nritems(buf, nritems); + csum_tree_block_size(buf, BTRFS_CRC32_SIZE, 0); + ret = pwrite(fd, buf->data, cfg->nodesize, cfg->blocks[4]); + if (ret != cfg->nodesize) { + ret = (ret < 0 ? -errno : -EIO); + goto out; + } + + /* create the FS root */ + memset(buf->data + sizeof(struct btrfs_header), 0, + cfg->nodesize - sizeof(struct btrfs_header)); + btrfs_set_header_bytenr(buf, cfg->blocks[5]); + btrfs_set_header_owner(buf, BTRFS_FS_TREE_OBJECTID); + btrfs_set_header_nritems(buf, 0); + csum_tree_block_size(buf, BTRFS_CRC32_SIZE, 0); + ret = pwrite(fd, buf->data, cfg->nodesize, cfg->blocks[5]); + if (ret != cfg->nodesize) { + ret = (ret < 0 ? -errno : -EIO); + goto out; + } + /* finally create the csum root */ + memset(buf->data + sizeof(struct btrfs_header), 0, + cfg->nodesize - sizeof(struct btrfs_header)); + btrfs_set_header_bytenr(buf, cfg->blocks[6]); + btrfs_set_header_owner(buf, BTRFS_CSUM_TREE_OBJECTID); + btrfs_set_header_nritems(buf, 0); + csum_tree_block_size(buf, BTRFS_CRC32_SIZE, 0); + ret = pwrite(fd, buf->data, cfg->nodesize, cfg->blocks[6]); + if (ret != cfg->nodesize) { + ret = (ret < 0 ? -errno : -EIO); + goto out; + } + + /* and write out the super block */ + BUG_ON(sizeof(super) > cfg->sectorsize); + memset(buf->data, 0, BTRFS_SUPER_INFO_SIZE); + memcpy(buf->data, &super, sizeof(super)); + buf->len = BTRFS_SUPER_INFO_SIZE; + csum_tree_block_size(buf, BTRFS_CRC32_SIZE, 0); + ret = pwrite(fd, buf->data, BTRFS_SUPER_INFO_SIZE, cfg->blocks[0]); + if (ret != BTRFS_SUPER_INFO_SIZE) { + ret = (ret < 0 ? -errno : -EIO); + goto out; + } + + ret = 0; + +out: + free(buf); + return ret; +} + +static const struct btrfs_fs_feature { + const char *name; + u64 flag; + const char *desc; +} mkfs_features[] = { + { "mixed-bg", BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS, + "mixed data and metadata block groups" }, + { "extref", BTRFS_FEATURE_INCOMPAT_EXTENDED_IREF, + "increased hardlink limit per file to 65536" }, + { "raid56", BTRFS_FEATURE_INCOMPAT_RAID56, + "raid56 extended format" }, + { "skinny-metadata", BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA, + "reduced-size metadata extent refs" }, + { "no-holes", BTRFS_FEATURE_INCOMPAT_NO_HOLES, + "no explicit hole extents for files" }, + /* Keep this one last */ + { "list-all", BTRFS_FEATURE_LIST_ALL, NULL } +}; + +static int parse_one_fs_feature(const char *name, u64 *flags) +{ + int i; + int found = 0; + + for (i = 0; i < ARRAY_SIZE(mkfs_features); i++) { + if (name[0] == '^' && + !strcmp(mkfs_features[i].name, name + 1)) { + *flags &= ~ mkfs_features[i].flag; + found = 1; + } else if (!strcmp(mkfs_features[i].name, name)) { + *flags |= mkfs_features[i].flag; + found = 1; + } + } + + return !found; +} + +void btrfs_parse_features_to_string(char *buf, u64 flags) +{ + int i; + + buf[0] = 0; + + for (i = 0; i < ARRAY_SIZE(mkfs_features); i++) { + if (flags & mkfs_features[i].flag) { + if (*buf) + strcat(buf, ", "); + strcat(buf, mkfs_features[i].name); + } + } +} + +void btrfs_process_fs_features(u64 flags) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(mkfs_features); i++) { + if (flags & mkfs_features[i].flag) { + printf("Turning ON incompat feature '%s': %s\n", + mkfs_features[i].name, + mkfs_features[i].desc); + } + } +} + +void btrfs_list_all_fs_features(u64 mask_disallowed) +{ + int i; + + fprintf(stderr, "Filesystem features available:\n"); + for (i = 0; i < ARRAY_SIZE(mkfs_features) - 1; i++) { + char *is_default = ""; + + if (mkfs_features[i].flag & mask_disallowed) + continue; + if (mkfs_features[i].flag & BTRFS_MKFS_DEFAULT_FEATURES) + is_default = ", default"; + fprintf(stderr, "%-20s- %s (0x%llx%s)\n", + mkfs_features[i].name, + mkfs_features[i].desc, + mkfs_features[i].flag, + is_default); + } +} + +/* + * Return NULL if all features were parsed fine, otherwise return the name of + * the first unparsed. + */ +char* btrfs_parse_fs_features(char *namelist, u64 *flags) +{ + char *this_char; + char *save_ptr = NULL; /* Satisfy static checkers */ + + for (this_char = strtok_r(namelist, ",", &save_ptr); + this_char != NULL; + this_char = strtok_r(NULL, ",", &save_ptr)) { + if (parse_one_fs_feature(this_char, flags)) + return this_char; + } + + return NULL; +} + +u64 btrfs_device_size(int fd, struct stat *st) +{ + u64 size; + if (S_ISREG(st->st_mode)) { + return st->st_size; + } + if (!S_ISBLK(st->st_mode)) { + return 0; + } + if (ioctl(fd, BLKGETSIZE64, &size) >= 0) { + return size; + } + return 0; +} + +static int zero_blocks(int fd, off_t start, size_t len) +{ + char *buf = malloc(len); + int ret = 0; + ssize_t written; + + if (!buf) + return -ENOMEM; + memset(buf, 0, len); + written = pwrite(fd, buf, len, start); + if (written != len) + ret = -EIO; + free(buf); + return ret; +} + +#define ZERO_DEV_BYTES (2 * 1024 * 1024) + +/* don't write outside the device by clamping the region to the device size */ +static int zero_dev_clamped(int fd, off_t start, ssize_t len, u64 dev_size) +{ + off_t end = max(start, start + len); + +#ifdef __sparc__ + /* and don't overwrite the disk labels on sparc */ + start = max(start, 1024); + end = max(end, 1024); +#endif + + start = min_t(u64, start, dev_size); + end = min_t(u64, end, dev_size); + + return zero_blocks(fd, start, end - start); +} + +int btrfs_add_to_fsid(struct btrfs_trans_handle *trans, + struct btrfs_root *root, int fd, char *path, + u64 device_total_bytes, u32 io_width, u32 io_align, + u32 sectorsize) +{ + struct btrfs_super_block *disk_super; + struct btrfs_super_block *super = root->fs_info->super_copy; + struct btrfs_device *device; + struct btrfs_dev_item *dev_item; + char *buf = NULL; + u64 fs_total_bytes; + u64 num_devs; + int ret; + + device_total_bytes = (device_total_bytes / sectorsize) * sectorsize; + + device = kzalloc(sizeof(*device), GFP_NOFS); + if (!device) + goto err_nomem; + buf = kzalloc(sectorsize, GFP_NOFS); + if (!buf) + goto err_nomem; + BUG_ON(sizeof(*disk_super) > sectorsize); + + disk_super = (struct btrfs_super_block *)buf; + dev_item = &disk_super->dev_item; + + uuid_generate(device->uuid); + device->devid = 0; + device->type = 0; + device->io_width = io_width; + device->io_align = io_align; + device->sector_size = sectorsize; + device->fd = fd; + device->writeable = 1; + device->total_bytes = device_total_bytes; + device->bytes_used = 0; + device->total_ios = 0; + device->dev_root = root->fs_info->dev_root; + device->name = strdup(path); + if (!device->name) + goto err_nomem; + + INIT_LIST_HEAD(&device->dev_list); + ret = btrfs_add_device(trans, root, device); + BUG_ON(ret); + + fs_total_bytes = btrfs_super_total_bytes(super) + device_total_bytes; + btrfs_set_super_total_bytes(super, fs_total_bytes); + + num_devs = btrfs_super_num_devices(super) + 1; + btrfs_set_super_num_devices(super, num_devs); + + memcpy(disk_super, super, sizeof(*disk_super)); + + btrfs_set_super_bytenr(disk_super, BTRFS_SUPER_INFO_OFFSET); + btrfs_set_stack_device_id(dev_item, device->devid); + btrfs_set_stack_device_type(dev_item, device->type); + btrfs_set_stack_device_io_align(dev_item, device->io_align); + btrfs_set_stack_device_io_width(dev_item, device->io_width); + btrfs_set_stack_device_sector_size(dev_item, device->sector_size); + btrfs_set_stack_device_total_bytes(dev_item, device->total_bytes); + btrfs_set_stack_device_bytes_used(dev_item, device->bytes_used); + memcpy(&dev_item->uuid, device->uuid, BTRFS_UUID_SIZE); + + ret = pwrite(fd, buf, sectorsize, BTRFS_SUPER_INFO_OFFSET); + BUG_ON(ret != sectorsize); + + kfree(buf); + list_add(&device->dev_list, &root->fs_info->fs_devices->devices); + device->fs_devices = root->fs_info->fs_devices; + return 0; + +err_nomem: + kfree(device); + kfree(buf); + return -ENOMEM; +} + +static int btrfs_wipe_existing_sb(int fd) +{ + const char *off = NULL; + size_t len = 0; + loff_t offset; + char buf[BUFSIZ]; + int ret = 0; + blkid_probe pr = NULL; + + pr = blkid_new_probe(); + if (!pr) + return -1; + + if (blkid_probe_set_device(pr, fd, 0, 0)) { + ret = -1; + goto out; + } + + ret = blkid_probe_lookup_value(pr, "SBMAGIC_OFFSET", &off, NULL); + if (!ret) + ret = blkid_probe_lookup_value(pr, "SBMAGIC", NULL, &len); + + if (ret || len == 0 || off == NULL) { + /* + * If lookup fails, the probe did not find any values, eg. for + * a file image or a loop device. Soft error. + */ + ret = 1; + goto out; + } + + offset = strtoll(off, NULL, 10); + if (len > sizeof(buf)) + len = sizeof(buf); + + memset(buf, 0, len); + ret = pwrite(fd, buf, len, offset); + if (ret < 0) { + error("cannot wipe existing superblock: %s", strerror(errno)); + ret = -1; + } else if (ret != len) { + error("cannot wipe existing superblock: wrote %d of %zd", ret, len); + ret = -1; + } + fsync(fd); + +out: + blkid_free_probe(pr); + return ret; +} + +int btrfs_prepare_device(int fd, const char *file, int zero_end, + u64 *block_count_ret, u64 max_block_count, int discard) +{ + u64 block_count; + struct stat st; + int i, ret; + + ret = fstat(fd, &st); + if (ret < 0) { + error("unable to stat %s: %s", file, strerror(errno)); + return 1; + } + + block_count = btrfs_device_size(fd, &st); + if (block_count == 0) { + error("unable to determine size of %s", file); + return 1; + } + if (max_block_count) + block_count = min(block_count, max_block_count); + + if (discard) { + /* + * We intentionally ignore errors from the discard ioctl. It + * is not necessary for the mkfs functionality but just an + * optimization. + */ + if (discard_range(fd, 0, 0) == 0) { + printf("Performing full device TRIM (%s) ...\n", + pretty_size(block_count)); + discard_blocks(fd, 0, block_count); + } + } + + ret = zero_dev_clamped(fd, 0, ZERO_DEV_BYTES, block_count); + for (i = 0 ; !ret && i < BTRFS_SUPER_MIRROR_MAX; i++) + ret = zero_dev_clamped(fd, btrfs_sb_offset(i), + BTRFS_SUPER_INFO_SIZE, block_count); + if (!ret && zero_end) + ret = zero_dev_clamped(fd, block_count - ZERO_DEV_BYTES, + ZERO_DEV_BYTES, block_count); + + if (ret < 0) { + error("failed to zero device '%s': %s", file, strerror(-ret)); + return 1; + } + + ret = btrfs_wipe_existing_sb(fd); + if (ret < 0) { + error("cannot wipe superblocks on %s", file); + return 1; + } + + *block_count_ret = block_count; + return 0; +} + +int btrfs_make_root_dir(struct btrfs_trans_handle *trans, + struct btrfs_root *root, u64 objectid) +{ + int ret; + struct btrfs_inode_item inode_item; + time_t now = time(NULL); + + memset(&inode_item, 0, sizeof(inode_item)); + btrfs_set_stack_inode_generation(&inode_item, trans->transid); + btrfs_set_stack_inode_size(&inode_item, 0); + btrfs_set_stack_inode_nlink(&inode_item, 1); + btrfs_set_stack_inode_nbytes(&inode_item, root->nodesize); + btrfs_set_stack_inode_mode(&inode_item, S_IFDIR | 0755); + btrfs_set_stack_timespec_sec(&inode_item.atime, now); + btrfs_set_stack_timespec_nsec(&inode_item.atime, 0); + btrfs_set_stack_timespec_sec(&inode_item.ctime, now); + btrfs_set_stack_timespec_nsec(&inode_item.ctime, 0); + btrfs_set_stack_timespec_sec(&inode_item.mtime, now); + btrfs_set_stack_timespec_nsec(&inode_item.mtime, 0); + btrfs_set_stack_timespec_sec(&inode_item.otime, 0); + btrfs_set_stack_timespec_nsec(&inode_item.otime, 0); + + if (root->fs_info->tree_root == root) + btrfs_set_super_root_dir(root->fs_info->super_copy, objectid); + + ret = btrfs_insert_inode(trans, root, objectid, &inode_item); + if (ret) + goto error; + + ret = btrfs_insert_inode_ref(trans, root, "..", 2, objectid, objectid, 0); + if (ret) + goto error; + + btrfs_set_root_dirid(&root->root_item, objectid); + ret = 0; +error: + return ret; +} + +/* + * checks if a path is a block device node + * Returns negative errno on failure, otherwise + * returns 1 for blockdev, 0 for not-blockdev + */ +int is_block_device(const char *path) +{ + struct stat statbuf; + + if (stat(path, &statbuf) < 0) + return -errno; + + return !!S_ISBLK(statbuf.st_mode); +} + +/* + * check if given path is a mount point + * return 1 if yes. 0 if no. -1 for error + */ +int is_mount_point(const char *path) +{ + FILE *f; + struct mntent *mnt; + int ret = 0; + + f = setmntent("/proc/self/mounts", "r"); + if (f == NULL) + return -1; + + while ((mnt = getmntent(f)) != NULL) { + if (strcmp(mnt->mnt_dir, path)) + continue; + ret = 1; + break; + } + endmntent(f); + return ret; +} + +static int is_reg_file(const char *path) +{ + struct stat statbuf; + + if (stat(path, &statbuf) < 0) + return -errno; + return S_ISREG(statbuf.st_mode); +} + +/* + * This function checks if the given input parameter is + * an uuid or a path + * return <0 : some error in the given input + * return BTRFS_ARG_UNKNOWN: unknown input + * return BTRFS_ARG_UUID: given input is uuid + * return BTRFS_ARG_MNTPOINT: given input is path + * return BTRFS_ARG_REG: given input is regular file + * return BTRFS_ARG_BLKDEV: given input is block device + */ +int check_arg_type(const char *input) +{ + uuid_t uuid; + char path[PATH_MAX]; + + if (!input) + return -EINVAL; + + if (realpath(input, path)) { + if (is_block_device(path) == 1) + return BTRFS_ARG_BLKDEV; + + if (is_mount_point(path) == 1) + return BTRFS_ARG_MNTPOINT; + + if (is_reg_file(path)) + return BTRFS_ARG_REG; + + return BTRFS_ARG_UNKNOWN; + } + + if (strlen(input) == (BTRFS_UUID_UNPARSED_SIZE - 1) && + !uuid_parse(input, uuid)) + return BTRFS_ARG_UUID; + + return BTRFS_ARG_UNKNOWN; +} + +/* + * Find the mount point for a mounted device. + * On success, returns 0 with mountpoint in *mp. + * On failure, returns -errno (not mounted yields -EINVAL) + * Is noisy on failures, expects to be given a mounted device. + */ +int get_btrfs_mount(const char *dev, char *mp, size_t mp_size) +{ + int ret; + int fd = -1; + + ret = is_block_device(dev); + if (ret <= 0) { + if (!ret) { + error("not a block device: %s", dev); + ret = -EINVAL; + } else { + error("cannot check %s: %s", dev, strerror(-ret)); + } + goto out; + } + + fd = open(dev, O_RDONLY); + if (fd < 0) { + ret = -errno; + error("cannot open %s: %s", dev, strerror(errno)); + goto out; + } + + ret = check_mounted_where(fd, dev, mp, mp_size, NULL); + if (!ret) { + ret = -EINVAL; + } else { /* mounted, all good */ + ret = 0; + } +out: + if (fd != -1) + close(fd); + return ret; +} + +/* + * Given a pathname, return a filehandle to: + * the original pathname or, + * if the pathname is a mounted btrfs device, to its mountpoint. + * + * On error, return -1, errno should be set. + */ +int open_path_or_dev_mnt(const char *path, DIR **dirstream, int verbose) +{ + char mp[PATH_MAX]; + int ret; + + if (is_block_device(path)) { + ret = get_btrfs_mount(path, mp, sizeof(mp)); + if (ret < 0) { + /* not a mounted btrfs dev */ + error_on(verbose, "'%s' is not a mounted btrfs device", + path); + errno = EINVAL; + return -1; + } + ret = open_file_or_dir(mp, dirstream); + error_on(verbose && ret < 0, "can't access '%s': %s", + path, strerror(errno)); + } else { + ret = btrfs_open_dir(path, dirstream, 1); + } + + return ret; +} + +/* + * Do the following checks before calling open_file_or_dir(): + * 1: path is in a btrfs filesystem + * 2: path is a directory + */ +int btrfs_open_dir(const char *path, DIR **dirstream, int verbose) +{ + struct statfs stfs; + struct stat st; + int ret; + + if (statfs(path, &stfs) != 0) { + error_on(verbose, "cannot access '%s': %s", path, + strerror(errno)); + return -1; + } + + if (stfs.f_type != BTRFS_SUPER_MAGIC) { + error_on(verbose, "not a btrfs filesystem: %s", path); + return -2; + } + + if (stat(path, &st) != 0) { + error_on(verbose, "cannot access '%s': %s", path, + strerror(errno)); + return -1; + } + + if (!S_ISDIR(st.st_mode)) { + error_on(verbose, "not a directory: %s", path); + return -3; + } + + ret = open_file_or_dir(path, dirstream); + if (ret < 0) { + error_on(verbose, "cannot access '%s': %s", path, + strerror(errno)); + } + + return ret; +} + +/* checks if a device is a loop device */ +static int is_loop_device (const char* device) { + struct stat statbuf; + + if(stat(device, &statbuf) < 0) + return -errno; + + return (S_ISBLK(statbuf.st_mode) && + MAJOR(statbuf.st_rdev) == LOOP_MAJOR); +} + +/* + * Takes a loop device path (e.g. /dev/loop0) and returns + * the associated file (e.g. /images/my_btrfs.img) using + * loopdev API + */ +static int resolve_loop_device_with_loopdev(const char* loop_dev, char* loop_file) +{ + int fd; + int ret; + struct loop_info64 lo64; + + fd = open(loop_dev, O_RDONLY | O_NONBLOCK); + if (fd < 0) + return -errno; + ret = ioctl(fd, LOOP_GET_STATUS64, &lo64); + if (ret < 0) { + ret = -errno; + goto out; + } + + memcpy(loop_file, lo64.lo_file_name, sizeof(lo64.lo_file_name)); + loop_file[sizeof(lo64.lo_file_name)] = 0; + +out: + close(fd); + + return ret; +} + +/* Takes a loop device path (e.g. /dev/loop0) and returns + * the associated file (e.g. /images/my_btrfs.img) */ +static int resolve_loop_device(const char* loop_dev, char* loop_file, + int max_len) +{ + int ret; + FILE *f; + char fmt[20]; + char p[PATH_MAX]; + char real_loop_dev[PATH_MAX]; + + if (!realpath(loop_dev, real_loop_dev)) + return -errno; + snprintf(p, PATH_MAX, "/sys/block/%s/loop/backing_file", strrchr(real_loop_dev, '/')); + if (!(f = fopen(p, "r"))) { + if (errno == ENOENT) + /* + * It's possibly a partitioned loop device, which is + * resolvable with loopdev API. + */ + return resolve_loop_device_with_loopdev(loop_dev, loop_file); + return -errno; + } + + snprintf(fmt, 20, "%%%i[^\n]", max_len-1); + ret = fscanf(f, fmt, loop_file); + fclose(f); + if (ret == EOF) + return -errno; + + return 0; +} + +/* + * Checks whether a and b are identical or device + * files associated with the same block device + */ +static int is_same_blk_file(const char* a, const char* b) +{ + struct stat st_buf_a, st_buf_b; + char real_a[PATH_MAX]; + char real_b[PATH_MAX]; + + if (!realpath(a, real_a)) + strncpy_null(real_a, a); + + if (!realpath(b, real_b)) + strncpy_null(real_b, b); + + /* Identical path? */ + if (strcmp(real_a, real_b) == 0) + return 1; + + if (stat(a, &st_buf_a) < 0 || stat(b, &st_buf_b) < 0) { + if (errno == ENOENT) + return 0; + return -errno; + } + + /* Same blockdevice? */ + if (S_ISBLK(st_buf_a.st_mode) && S_ISBLK(st_buf_b.st_mode) && + st_buf_a.st_rdev == st_buf_b.st_rdev) { + return 1; + } + + /* Hardlink? */ + if (st_buf_a.st_dev == st_buf_b.st_dev && + st_buf_a.st_ino == st_buf_b.st_ino) { + return 1; + } + + return 0; +} + +/* checks if a and b are identical or device + * files associated with the same block device or + * if one file is a loop device that uses the other + * file. + */ +static int is_same_loop_file(const char* a, const char* b) +{ + char res_a[PATH_MAX]; + char res_b[PATH_MAX]; + const char* final_a = NULL; + const char* final_b = NULL; + int ret; + + /* Resolve a if it is a loop device */ + if((ret = is_loop_device(a)) < 0) { + if (ret == -ENOENT) + return 0; + return ret; + } else if (ret) { + ret = resolve_loop_device(a, res_a, sizeof(res_a)); + if (ret < 0) { + if (errno != EPERM) + return ret; + } else { + final_a = res_a; + } + } else { + final_a = a; + } + + /* Resolve b if it is a loop device */ + if ((ret = is_loop_device(b)) < 0) { + if (ret == -ENOENT) + return 0; + return ret; + } else if (ret) { + ret = resolve_loop_device(b, res_b, sizeof(res_b)); + if (ret < 0) { + if (errno != EPERM) + return ret; + } else { + final_b = res_b; + } + } else { + final_b = b; + } + + return is_same_blk_file(final_a, final_b); +} + +/* Checks if a file exists and is a block or regular file*/ +static int is_existing_blk_or_reg_file(const char* filename) +{ + struct stat st_buf; + + if(stat(filename, &st_buf) < 0) { + if(errno == ENOENT) + return 0; + else + return -errno; + } + + return (S_ISBLK(st_buf.st_mode) || S_ISREG(st_buf.st_mode)); +} + +/* Checks if a file is used (directly or indirectly via a loop device) + * by a device in fs_devices + */ +static int blk_file_in_dev_list(struct btrfs_fs_devices* fs_devices, + const char* file) +{ + int ret; + struct list_head *head; + struct list_head *cur; + struct btrfs_device *device; + + head = &fs_devices->devices; + list_for_each(cur, head) { + device = list_entry(cur, struct btrfs_device, dev_list); + + if((ret = is_same_loop_file(device->name, file))) + return ret; + } + + return 0; +} + +/* + * Resolve a pathname to a device mapper node to /dev/mapper/<name> + * Returns NULL on invalid input or malloc failure; Other failures + * will be handled by the caller using the input pathame. + */ +char *canonicalize_dm_name(const char *ptname) +{ + FILE *f; + size_t sz; + char path[PATH_MAX], name[PATH_MAX], *res = NULL; + + if (!ptname || !*ptname) + return NULL; + + snprintf(path, sizeof(path), "/sys/block/%s/dm/name", ptname); + if (!(f = fopen(path, "r"))) + return NULL; + + /* read <name>\n from sysfs */ + if (fgets(name, sizeof(name), f) && (sz = strlen(name)) > 1) { + name[sz - 1] = '\0'; + snprintf(path, sizeof(path), "/dev/mapper/%s", name); + + if (access(path, F_OK) == 0) + res = strdup(path); + } + fclose(f); + return res; +} + +/* + * Resolve a pathname to a canonical device node, e.g. /dev/sda1 or + * to a device mapper pathname. + * Returns NULL on invalid input or malloc failure; Other failures + * will be handled by the caller using the input pathame. + */ +char *canonicalize_path(const char *path) +{ + char *canonical, *p; + + if (!path || !*path) + return NULL; + + canonical = realpath(path, NULL); + if (!canonical) + return strdup(path); + p = strrchr(canonical, '/'); + if (p && strncmp(p, "/dm-", 4) == 0 && isdigit(*(p + 4))) { + char *dm = canonicalize_dm_name(p + 1); + + if (dm) { + free(canonical); + return dm; + } + } + return canonical; +} + +/* + * returns 1 if the device was mounted, < 0 on error or 0 if everything + * is safe to continue. + */ +int check_mounted(const char* file) +{ + int fd; + int ret; + + fd = open(file, O_RDONLY); + if (fd < 0) { + error("mount check: cannot open %s: %s", file, + strerror(errno)); + return -errno; + } + + ret = check_mounted_where(fd, file, NULL, 0, NULL); + close(fd); + + return ret; +} + +int check_mounted_where(int fd, const char *file, char *where, int size, + struct btrfs_fs_devices **fs_dev_ret) +{ + int ret; + u64 total_devs = 1; + int is_btrfs; + struct btrfs_fs_devices *fs_devices_mnt = NULL; + FILE *f; + struct mntent *mnt; + + /* scan the initial device */ + ret = btrfs_scan_one_device(fd, file, &fs_devices_mnt, + &total_devs, BTRFS_SUPER_INFO_OFFSET, 0); + is_btrfs = (ret >= 0); + + /* scan other devices */ + if (is_btrfs && total_devs > 1) { + ret = btrfs_scan_lblkid(); + if (ret) + return ret; + } + + /* iterate over the list of currently mounted filesystems */ + if ((f = setmntent ("/proc/self/mounts", "r")) == NULL) + return -errno; + + while ((mnt = getmntent (f)) != NULL) { + if(is_btrfs) { + if(strcmp(mnt->mnt_type, "btrfs") != 0) + continue; + + ret = blk_file_in_dev_list(fs_devices_mnt, mnt->mnt_fsname); + } else { + /* ignore entries in the mount table that are not + associated with a file*/ + if((ret = is_existing_blk_or_reg_file(mnt->mnt_fsname)) < 0) + goto out_mntloop_err; + else if(!ret) + continue; + + ret = is_same_loop_file(file, mnt->mnt_fsname); + } + + if(ret < 0) + goto out_mntloop_err; + else if(ret) + break; + } + + /* Did we find an entry in mnt table? */ + if (mnt && size && where) { + strncpy(where, mnt->mnt_dir, size); + where[size-1] = 0; + } + if (fs_dev_ret) + *fs_dev_ret = fs_devices_mnt; + + ret = (mnt != NULL); + +out_mntloop_err: + endmntent (f); + + return ret; +} + +struct pending_dir { + struct list_head list; + char name[PATH_MAX]; +}; + +int btrfs_register_one_device(const char *fname) +{ + struct btrfs_ioctl_vol_args args; + int fd; + int ret; + + fd = open("/dev/btrfs-control", O_RDWR); + if (fd < 0) { + warning( + "failed to open /dev/btrfs-control, skipping device registration: %s", + strerror(errno)); + return -errno; + } + memset(&args, 0, sizeof(args)); + strncpy_null(args.name, fname); + ret = ioctl(fd, BTRFS_IOC_SCAN_DEV, &args); + if (ret < 0) { + error("device scan failed on '%s': %s", fname, + strerror(errno)); + ret = -errno; + } + close(fd); + return ret; +} + +/* + * Register all devices in the fs_uuid list created in the user + * space. Ensure btrfs_scan_lblkid() is called before this func. + */ +int btrfs_register_all_devices(void) +{ + int err = 0; + int ret = 0; + struct btrfs_fs_devices *fs_devices; + struct btrfs_device *device; + struct list_head *all_uuids; + + all_uuids = btrfs_scanned_uuids(); + + list_for_each_entry(fs_devices, all_uuids, list) { + list_for_each_entry(device, &fs_devices->devices, dev_list) { + if (*device->name) + err = btrfs_register_one_device(device->name); + + if (err) + ret++; + } + } + + return ret; +} + +int btrfs_device_already_in_root(struct btrfs_root *root, int fd, + int super_offset) +{ + struct btrfs_super_block *disk_super; + char *buf; + int ret = 0; + + buf = malloc(BTRFS_SUPER_INFO_SIZE); + if (!buf) { + ret = -ENOMEM; + goto out; + } + ret = pread(fd, buf, BTRFS_SUPER_INFO_SIZE, super_offset); + if (ret != BTRFS_SUPER_INFO_SIZE) + goto brelse; + + ret = 0; + disk_super = (struct btrfs_super_block *)buf; + if (btrfs_super_magic(disk_super) != BTRFS_MAGIC) + goto brelse; + + if (!memcmp(disk_super->fsid, root->fs_info->super_copy->fsid, + BTRFS_FSID_SIZE)) + ret = 1; +brelse: + free(buf); +out: + return ret; +} + +/* + * Note: this function uses a static per-thread buffer. Do not call this + * function more than 10 times within one argument list! + */ +const char *pretty_size_mode(u64 size, unsigned mode) +{ + static __thread int ps_index = 0; + static __thread char ps_array[10][32]; + char *ret; + + ret = ps_array[ps_index]; + ps_index++; + ps_index %= 10; + (void)pretty_size_snprintf(size, ret, 32, mode); + + return ret; +} + +static const char* unit_suffix_binary[] = + { "B", "KiB", "MiB", "GiB", "TiB", "PiB", "EiB"}; +static const char* unit_suffix_decimal[] = + { "B", "kB", "MB", "GB", "TB", "PB", "EB"}; + +int pretty_size_snprintf(u64 size, char *str, size_t str_size, unsigned unit_mode) +{ + int num_divs; + float fraction; + u64 base = 0; + int mult = 0; + const char** suffix = NULL; + u64 last_size; + + if (str_size == 0) + return 0; + + if ((unit_mode & ~UNITS_MODE_MASK) == UNITS_RAW) { + snprintf(str, str_size, "%llu", size); + return 0; + } + + if ((unit_mode & ~UNITS_MODE_MASK) == UNITS_BINARY) { + base = 1024; + mult = 1024; + suffix = unit_suffix_binary; + } else if ((unit_mode & ~UNITS_MODE_MASK) == UNITS_DECIMAL) { + base = 1000; + mult = 1000; + suffix = unit_suffix_decimal; + } + + /* Unknown mode */ + if (!base) { + fprintf(stderr, "INTERNAL ERROR: unknown unit base, mode %d\n", + unit_mode); + assert(0); + return -1; + } + + num_divs = 0; + last_size = size; + switch (unit_mode & UNITS_MODE_MASK) { + case UNITS_TBYTES: base *= mult; num_divs++; + case UNITS_GBYTES: base *= mult; num_divs++; + case UNITS_MBYTES: base *= mult; num_divs++; + case UNITS_KBYTES: num_divs++; + break; + case UNITS_BYTES: + base = 1; + num_divs = 0; + break; + default: + while (size >= mult) { + last_size = size; + size /= mult; + num_divs++; + } + /* + * If the value is smaller than base, we didn't do any + * division, in that case, base should be 1, not original + * base, or the unit will be wrong + */ + if (num_divs == 0) + base = 1; + } + + if (num_divs >= ARRAY_SIZE(unit_suffix_binary)) { + str[0] = '\0'; + printf("INTERNAL ERROR: unsupported unit suffix, index %d\n", + num_divs); + assert(0); + return -1; + } + fraction = (float)last_size / base; + + return snprintf(str, str_size, "%.2f%s", fraction, suffix[num_divs]); +} + +/* + * __strncpy_null - strncpy with null termination + * @dest: the target array + * @src: the source string + * @n: maximum bytes to copy (size of *dest) + * + * Like strncpy, but ensures destination is null-terminated. + * + * Copies the string pointed to by src, including the terminating null + * byte ('\0'), to the buffer pointed to by dest, up to a maximum + * of n bytes. Then ensure that dest is null-terminated. + */ +char *__strncpy_null(char *dest, const char *src, size_t n) +{ + strncpy(dest, src, n); + if (n > 0) + dest[n - 1] = '\0'; + return dest; +} + +/* + * Checks to make sure that the label matches our requirements. + * Returns: + 0 if everything is safe and usable + -1 if the label is too long + */ +static int check_label(const char *input) +{ + int len = strlen(input); + + if (len > BTRFS_LABEL_SIZE - 1) { + error("label %s is too long (max %d)", input, + BTRFS_LABEL_SIZE - 1); + return -1; + } + + return 0; +} + +static int set_label_unmounted(const char *dev, const char *label) +{ + struct btrfs_trans_handle *trans; + struct btrfs_root *root; + int ret; + + ret = check_mounted(dev); + if (ret < 0) { + error("checking mount status of %s failed: %d", dev, ret); + return -1; + } + if (ret > 0) { + error("device %s is mounted, use mount point", dev); + return -1; + } + + /* Open the super_block at the default location + * and as read-write. + */ + root = open_ctree(dev, 0, OPEN_CTREE_WRITES); + if (!root) /* errors are printed by open_ctree() */ + return -1; + + trans = btrfs_start_transaction(root, 1); + __strncpy_null(root->fs_info->super_copy->label, label, BTRFS_LABEL_SIZE - 1); + + btrfs_commit_transaction(trans, root); + + /* Now we close it since we are done. */ + close_ctree(root); + return 0; +} + +static int set_label_mounted(const char *mount_path, const char *labelp) +{ + int fd; + char label[BTRFS_LABEL_SIZE]; + + fd = open(mount_path, O_RDONLY | O_NOATIME); + if (fd < 0) { + error("unable to access %s: %s", mount_path, strerror(errno)); + return -1; + } + + memset(label, 0, sizeof(label)); + __strncpy_null(label, labelp, BTRFS_LABEL_SIZE - 1); + if (ioctl(fd, BTRFS_IOC_SET_FSLABEL, label) < 0) { + error("unable to set label of %s: %s", mount_path, + strerror(errno)); + close(fd); + return -1; + } + + close(fd); + return 0; +} + +int get_label_unmounted(const char *dev, char *label) +{ + struct btrfs_root *root; + int ret; + + ret = check_mounted(dev); + if (ret < 0) { + error("checking mount status of %s failed: %d", dev, ret); + return -1; + } + + /* Open the super_block at the default location + * and as read-only. + */ + root = open_ctree(dev, 0, 0); + if(!root) + return -1; + + __strncpy_null(label, root->fs_info->super_copy->label, + BTRFS_LABEL_SIZE - 1); + + /* Now we close it since we are done. */ + close_ctree(root); + return 0; +} + +/* + * If a partition is mounted, try to get the filesystem label via its + * mounted path rather than device. Return the corresponding error + * the user specified the device path. + */ +int get_label_mounted(const char *mount_path, char *labelp) +{ + char label[BTRFS_LABEL_SIZE]; + int fd; + int ret; + + fd = open(mount_path, O_RDONLY | O_NOATIME); + if (fd < 0) { + error("unable to access %s: %s", mount_path, strerror(errno)); + return -1; + } + + memset(label, '\0', sizeof(label)); + ret = ioctl(fd, BTRFS_IOC_GET_FSLABEL, label); + if (ret < 0) { + if (errno != ENOTTY) + error("unable to get label of %s: %s", mount_path, + strerror(errno)); + ret = -errno; + close(fd); + return ret; + } + + __strncpy_null(labelp, label, BTRFS_LABEL_SIZE - 1); + close(fd); + return 0; +} + +int get_label(const char *btrfs_dev, char *label) +{ + int ret; + + ret = is_existing_blk_or_reg_file(btrfs_dev); + if (!ret) + ret = get_label_mounted(btrfs_dev, label); + else if (ret > 0) + ret = get_label_unmounted(btrfs_dev, label); + + return ret; +} + +int set_label(const char *btrfs_dev, const char *label) +{ + int ret; + + if (check_label(label)) + return -1; + + ret = is_existing_blk_or_reg_file(btrfs_dev); + if (!ret) + ret = set_label_mounted(btrfs_dev, label); + else if (ret > 0) + ret = set_label_unmounted(btrfs_dev, label); + + return ret; +} + +/* + * A not-so-good version fls64. No fascinating optimization since + * no one except parse_size use it + */ +static int fls64(u64 x) +{ + int i; + + for (i = 0; i <64; i++) + if (x << i & (1ULL << 63)) + return 64 - i; + return 64 - i; +} + +u64 parse_size(char *s) +{ + char c; + char *endptr; + u64 mult = 1; + u64 ret; + + if (!s) { + error("size value is empty"); + exit(1); + } + if (s[0] == '-') { + error("size value '%s' is less equal than 0", s); + exit(1); + } + ret = strtoull(s, &endptr, 10); + if (endptr == s) { + error("size value '%s' is invalid", s); + exit(1); + } + if (endptr[0] && endptr[1]) { + error("illegal suffix contains character '%c' in wrong position", + endptr[1]); + exit(1); + } + /* + * strtoll returns LLONG_MAX when overflow, if this happens, + * need to call strtoull to get the real size + */ + if (errno == ERANGE && ret == ULLONG_MAX) { + error("size value '%s' is too large for u64", s); + exit(1); + } + if (endptr[0]) { + c = tolower(endptr[0]); + switch (c) { + case 'e': + mult *= 1024; + /* fallthrough */ + case 'p': + mult *= 1024; + /* fallthrough */ + case 't': + mult *= 1024; + /* fallthrough */ + case 'g': + mult *= 1024; + /* fallthrough */ + case 'm': + mult *= 1024; + /* fallthrough */ + case 'k': + mult *= 1024; + /* fallthrough */ + case 'b': + break; + default: + error("unknown size descriptor '%c'", c); + exit(1); + } + } + /* Check whether ret * mult overflow */ + if (fls64(ret) + fls64(mult) - 1 > 64) { + error("size value '%s' is too large for u64", s); + exit(1); + } + ret *= mult; + return ret; +} + +u64 parse_qgroupid(const char *p) +{ + char *s = strchr(p, '/'); + const char *ptr_src_end = p + strlen(p); + char *ptr_parse_end = NULL; + u64 level; + u64 id; + int fd; + int ret = 0; + + if (p[0] == '/') + goto path; + + /* Numeric format like '0/257' is the primary case */ + if (!s) { + id = strtoull(p, &ptr_parse_end, 10); + if (ptr_parse_end != ptr_src_end) + goto path; + return id; + } + level = strtoull(p, &ptr_parse_end, 10); + if (ptr_parse_end != s) + goto path; + + id = strtoull(s + 1, &ptr_parse_end, 10); + if (ptr_parse_end != ptr_src_end) + goto path; + + return (level << BTRFS_QGROUP_LEVEL_SHIFT) | id; + +path: + /* Path format like subv at 'my_subvol' is the fallback case */ + ret = test_issubvolume(p); + if (ret < 0 || !ret) + goto err; + fd = open(p, O_RDONLY); + if (fd < 0) + goto err; + ret = lookup_ino_rootid(fd, &id); + close(fd); + if (ret < 0) + goto err; + return id; + +err: + error("invalid qgroupid or subvolume path: %s", p); + exit(-1); +} + +int open_file_or_dir3(const char *fname, DIR **dirstream, int open_flags) +{ + int ret; + struct stat st; + int fd; + + ret = stat(fname, &st); + if (ret < 0) { + return -1; + } + if (S_ISDIR(st.st_mode)) { + *dirstream = opendir(fname); + if (!*dirstream) + return -1; + fd = dirfd(*dirstream); + } else if (S_ISREG(st.st_mode) || S_ISLNK(st.st_mode)) { + fd = open(fname, open_flags); + } else { + /* + * we set this on purpose, in case the caller output + * strerror(errno) as success + */ + errno = EINVAL; + return -1; + } + if (fd < 0) { + fd = -1; + if (*dirstream) { + closedir(*dirstream); + *dirstream = NULL; + } + } + return fd; +} + +int open_file_or_dir(const char *fname, DIR **dirstream) +{ + return open_file_or_dir3(fname, dirstream, O_RDWR); +} + +void close_file_or_dir(int fd, DIR *dirstream) +{ + if (dirstream) + closedir(dirstream); + else if (fd >= 0) + close(fd); +} + +int get_device_info(int fd, u64 devid, + struct btrfs_ioctl_dev_info_args *di_args) +{ + int ret; + + di_args->devid = devid; + memset(&di_args->uuid, '\0', sizeof(di_args->uuid)); + + ret = ioctl(fd, BTRFS_IOC_DEV_INFO, di_args); + return ret < 0 ? -errno : 0; +} + +static u64 find_max_device_id(struct btrfs_ioctl_search_args *search_args, + int nr_items) +{ + struct btrfs_dev_item *dev_item; + char *buf = search_args->buf; + + buf += (nr_items - 1) * (sizeof(struct btrfs_ioctl_search_header) + + sizeof(struct btrfs_dev_item)); + buf += sizeof(struct btrfs_ioctl_search_header); + + dev_item = (struct btrfs_dev_item *)buf; + + return btrfs_stack_device_id(dev_item); +} + +static int search_chunk_tree_for_fs_info(int fd, + struct btrfs_ioctl_fs_info_args *fi_args) +{ + int ret; + int max_items; + u64 start_devid = 1; + struct btrfs_ioctl_search_args search_args; + struct btrfs_ioctl_search_key *search_key = &search_args.key; + + fi_args->num_devices = 0; + + max_items = BTRFS_SEARCH_ARGS_BUFSIZE + / (sizeof(struct btrfs_ioctl_search_header) + + sizeof(struct btrfs_dev_item)); + + search_key->tree_id = BTRFS_CHUNK_TREE_OBJECTID; + search_key->min_objectid = BTRFS_DEV_ITEMS_OBJECTID; + search_key->max_objectid = BTRFS_DEV_ITEMS_OBJECTID; + search_key->min_type = BTRFS_DEV_ITEM_KEY; + search_key->max_type = BTRFS_DEV_ITEM_KEY; + search_key->min_transid = 0; + search_key->max_transid = (u64)-1; + search_key->nr_items = max_items; + search_key->max_offset = (u64)-1; + +again: + search_key->min_offset = start_devid; + + ret = ioctl(fd, BTRFS_IOC_TREE_SEARCH, &search_args); + if (ret < 0) + return -errno; + + fi_args->num_devices += (u64)search_key->nr_items; + + if (search_key->nr_items == max_items) { + start_devid = find_max_device_id(&search_args, + search_key->nr_items) + 1; + goto again; + } + + /* get the lastest max_id to stay consistent with the num_devices */ + if (search_key->nr_items == 0) + /* + * last tree_search returns an empty buf, use the devid of + * the last dev_item of the previous tree_search + */ + fi_args->max_id = start_devid - 1; + else + fi_args->max_id = find_max_device_id(&search_args, + search_key->nr_items); + + return 0; +} + +/* + * For a given path, fill in the ioctl fs_ and info_ args. + * If the path is a btrfs mountpoint, fill info for all devices. + * If the path is a btrfs device, fill in only that device. + * + * The path provided must be either on a mounted btrfs fs, + * or be a mounted btrfs device. + * + * Returns 0 on success, or a negative errno. + */ +int get_fs_info(char *path, struct btrfs_ioctl_fs_info_args *fi_args, + struct btrfs_ioctl_dev_info_args **di_ret) +{ + int fd = -1; + int ret = 0; + int ndevs = 0; + int i = 0; + int replacing = 0; + struct btrfs_fs_devices *fs_devices_mnt = NULL; + struct btrfs_ioctl_dev_info_args *di_args; + struct btrfs_ioctl_dev_info_args tmp; + char mp[PATH_MAX]; + DIR *dirstream = NULL; + + memset(fi_args, 0, sizeof(*fi_args)); + + if (is_block_device(path) == 1) { + struct btrfs_super_block *disk_super; + char buf[BTRFS_SUPER_INFO_SIZE]; + u64 devid; + + /* Ensure it's mounted, then set path to the mountpoint */ + fd = open(path, O_RDONLY); + if (fd < 0) { + ret = -errno; + error("cannot open %s: %s", path, strerror(errno)); + goto out; + } + ret = check_mounted_where(fd, path, mp, sizeof(mp), + &fs_devices_mnt); + if (!ret) { + ret = -EINVAL; + goto out; + } + if (ret < 0) + goto out; + path = mp; + /* Only fill in this one device */ + fi_args->num_devices = 1; + + disk_super = (struct btrfs_super_block *)buf; + ret = btrfs_read_dev_super(fd, disk_super, + BTRFS_SUPER_INFO_OFFSET, 0); + if (ret < 0) { + ret = -EIO; + goto out; + } + devid = btrfs_stack_device_id(&disk_super->dev_item); + + fi_args->max_id = devid; + i = devid; + + memcpy(fi_args->fsid, fs_devices_mnt->fsid, BTRFS_FSID_SIZE); + close(fd); + } + + /* at this point path must not be for a block device */ + fd = open_file_or_dir(path, &dirstream); + if (fd < 0) { + ret = -errno; + goto out; + } + + /* fill in fi_args if not just a single device */ + if (fi_args->num_devices != 1) { + ret = ioctl(fd, BTRFS_IOC_FS_INFO, fi_args); + if (ret < 0) { + ret = -errno; + goto out; + } + + /* + * The fs_args->num_devices does not include seed devices + */ + ret = search_chunk_tree_for_fs_info(fd, fi_args); + if (ret) + goto out; + + /* + * search_chunk_tree_for_fs_info() will lacks the devid 0 + * so manual probe for it here. + */ + ret = get_device_info(fd, 0, &tmp); + if (!ret) { + fi_args->num_devices++; + ndevs++; + replacing = 1; + if (i == 0) + i++; + } + } + + if (!fi_args->num_devices) + goto out; + + di_args = *di_ret = malloc((fi_args->num_devices) * sizeof(*di_args)); + if (!di_args) { + ret = -errno; + goto out; + } + + if (replacing) + memcpy(di_args, &tmp, sizeof(tmp)); + for (; i <= fi_args->max_id; ++i) { + ret = get_device_info(fd, i, &di_args[ndevs]); + if (ret == -ENODEV) + continue; + if (ret) + goto out; + ndevs++; + } + + /* + * only when the only dev we wanted to find is not there then + * let any error be returned + */ + if (fi_args->num_devices != 1) { + BUG_ON(ndevs == 0); + ret = 0; + } + +out: + close_file_or_dir(fd, dirstream); + return ret; +} + +#define isoctal(c) (((c) & ~7) == '0') + +static inline void translate(char *f, char *t) +{ + while (*f != '\0') { + if (*f == '\\' && + isoctal(f[1]) && isoctal(f[2]) && isoctal(f[3])) { + *t++ = 64*(f[1] & 7) + 8*(f[2] & 7) + (f[3] & 7); + f += 4; + } else + *t++ = *f++; + } + *t = '\0'; + return; +} + +/* + * Checks if the swap device. + * Returns 1 if swap device, < 0 on error or 0 if not swap device. + */ +static int is_swap_device(const char *file) +{ + FILE *f; + struct stat st_buf; + dev_t dev; + ino_t ino = 0; + char tmp[PATH_MAX]; + char buf[PATH_MAX]; + char *cp; + int ret = 0; + + if (stat(file, &st_buf) < 0) + return -errno; + if (S_ISBLK(st_buf.st_mode)) + dev = st_buf.st_rdev; + else if (S_ISREG(st_buf.st_mode)) { + dev = st_buf.st_dev; + ino = st_buf.st_ino; + } else + return 0; + + if ((f = fopen("/proc/swaps", "r")) == NULL) + return 0; + + /* skip the first line */ + if (fgets(tmp, sizeof(tmp), f) == NULL) + goto out; + + while (fgets(tmp, sizeof(tmp), f) != NULL) { + if ((cp = strchr(tmp, ' ')) != NULL) + *cp = '\0'; + if ((cp = strchr(tmp, '\t')) != NULL) + *cp = '\0'; + translate(tmp, buf); + if (stat(buf, &st_buf) != 0) + continue; + if (S_ISBLK(st_buf.st_mode)) { + if (dev == st_buf.st_rdev) { + ret = 1; + break; + } + } else if (S_ISREG(st_buf.st_mode)) { + if (dev == st_buf.st_dev && ino == st_buf.st_ino) { + ret = 1; + break; + } + } + } + +out: + fclose(f); + + return ret; +} + +/* + * Check for existing filesystem or partition table on device. + * Returns: + * 1 for existing fs or partition + * 0 for nothing found + * -1 for internal error + */ +static int check_overwrite(const char *device) +{ + const char *type; + blkid_probe pr = NULL; + int ret; + blkid_loff_t size; + + if (!device || !*device) + return 0; + + ret = -1; /* will reset on success of all setup calls */ + + pr = blkid_new_probe_from_filename(device); + if (!pr) + goto out; + + size = blkid_probe_get_size(pr); + if (size < 0) + goto out; + + /* nothing to overwrite on a 0-length device */ + if (size == 0) { + ret = 0; + goto out; + } + + ret = blkid_probe_enable_partitions(pr, 1); + if (ret < 0) + goto out; + + ret = blkid_do_fullprobe(pr); + if (ret < 0) + goto out; + + /* + * Blkid returns 1 for nothing found and 0 when it finds a signature, + * but we want the exact opposite, so reverse the return value here. + * + * In addition print some useful diagnostics about what actually is + * on the device. + */ + if (ret) { + ret = 0; + goto out; + } + + if (!blkid_probe_lookup_value(pr, "TYPE", &type, NULL)) { + fprintf(stderr, + "%s appears to contain an existing " + "filesystem (%s).\n", device, type); + } else if (!blkid_probe_lookup_value(pr, "PTTYPE", &type, NULL)) { + fprintf(stderr, + "%s appears to contain a partition " + "table (%s).\n", device, type); + } else { + fprintf(stderr, + "%s appears to contain something weird " + "according to blkid\n", device); + } + ret = 1; + +out: + if (pr) + blkid_free_probe(pr); + if (ret == -1) + fprintf(stderr, + "probe of %s failed, cannot detect " + "existing filesystem.\n", device); + return ret; +} + +static int group_profile_devs_min(u64 flag) +{ + switch (flag & BTRFS_BLOCK_GROUP_PROFILE_MASK) { + case 0: /* single */ + case BTRFS_BLOCK_GROUP_DUP: + return 1; + case BTRFS_BLOCK_GROUP_RAID0: + case BTRFS_BLOCK_GROUP_RAID1: + case BTRFS_BLOCK_GROUP_RAID5: + return 2; + case BTRFS_BLOCK_GROUP_RAID6: + return 3; + case BTRFS_BLOCK_GROUP_RAID10: + return 4; + default: + return -1; + } +} + +int test_num_disk_vs_raid(u64 metadata_profile, u64 data_profile, + u64 dev_cnt, int mixed, int ssd) +{ + u64 allowed = 0; + + switch (dev_cnt) { + default: + case 4: + allowed |= BTRFS_BLOCK_GROUP_RAID10; + case 3: + allowed |= BTRFS_BLOCK_GROUP_RAID6; + case 2: + allowed |= BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1 | + BTRFS_BLOCK_GROUP_RAID5; + case 1: + allowed |= BTRFS_BLOCK_GROUP_DUP; + } + + if (dev_cnt > 1 && + ((metadata_profile | data_profile) & BTRFS_BLOCK_GROUP_DUP)) { + warning("DUP is not recommended on filesystem with multiple devices"); + } + if (metadata_profile & ~allowed) { + fprintf(stderr, + "ERROR: unable to create FS with metadata profile %s " + "(have %llu devices but %d devices are required)\n", + btrfs_group_profile_str(metadata_profile), dev_cnt, + group_profile_devs_min(metadata_profile)); + return 1; + } + if (data_profile & ~allowed) { + fprintf(stderr, + "ERROR: unable to create FS with data profile %s " + "(have %llu devices but %d devices are required)\n", + btrfs_group_profile_str(data_profile), dev_cnt, + group_profile_devs_min(data_profile)); + return 1; + } + + warning_on(!mixed && (data_profile & BTRFS_BLOCK_GROUP_DUP) && ssd, + "DUP may not actually lead to 2 copies on the device, see manual page"); + + return 0; +} + +int group_profile_max_safe_loss(u64 flags) +{ + switch (flags & BTRFS_BLOCK_GROUP_PROFILE_MASK) { + case 0: /* single */ + case BTRFS_BLOCK_GROUP_DUP: + case BTRFS_BLOCK_GROUP_RAID0: + return 0; + case BTRFS_BLOCK_GROUP_RAID1: + case BTRFS_BLOCK_GROUP_RAID5: + case BTRFS_BLOCK_GROUP_RAID10: + return 1; + case BTRFS_BLOCK_GROUP_RAID6: + return 2; + default: + return -1; + } +} + +/* + * Check if a device is suitable for btrfs + * returns: + * 1: something is wrong, an error is printed + * 0: all is fine + */ +int test_dev_for_mkfs(const char *file, int force_overwrite) +{ + int ret, fd; + struct stat st; + + ret = is_swap_device(file); + if (ret < 0) { + error("checking status of %s: %s", file, strerror(-ret)); + return 1; + } + if (ret == 1) { + error("%s is a swap device", file); + return 1; + } + if (!force_overwrite) { + if (check_overwrite(file)) { + error("use the -f option to force overwrite of %s", + file); + return 1; + } + } + ret = check_mounted(file); + if (ret < 0) { + error("cannot check mount status of %s: %s", file, + strerror(-ret)); + return 1; + } + if (ret == 1) { + error("%s is mounted", file); + return 1; + } + /* check if the device is busy */ + fd = open(file, O_RDWR|O_EXCL); + if (fd < 0) { + error("unable to open %s: %s", file, strerror(errno)); + return 1; + } + if (fstat(fd, &st)) { + error("unable to stat %s: %s", file, strerror(errno)); + close(fd); + return 1; + } + if (!S_ISBLK(st.st_mode)) { + error("%s is not a block device", file); + close(fd); + return 1; + } + close(fd); + return 0; +} + +int btrfs_scan_lblkid(void) +{ + int fd = -1; + int ret; + u64 num_devices; + struct btrfs_fs_devices *tmp_devices; + blkid_dev_iterate iter = NULL; + blkid_dev dev = NULL; + blkid_cache cache = NULL; + char path[PATH_MAX]; + + if (btrfs_scan_done) + return 0; + + if (blkid_get_cache(&cache, NULL) < 0) { + error("blkid cache get failed"); + return 1; + } + blkid_probe_all(cache); + iter = blkid_dev_iterate_begin(cache); + blkid_dev_set_search(iter, "TYPE", "btrfs"); + while (blkid_dev_next(iter, &dev) == 0) { + dev = blkid_verify(cache, dev); + if (!dev) + continue; + /* if we are here its definitely a btrfs disk*/ + strncpy_null(path, blkid_dev_devname(dev)); + + fd = open(path, O_RDONLY); + if (fd < 0) { + error("cannot open %s: %s", path, strerror(errno)); + continue; + } + ret = btrfs_scan_one_device(fd, path, &tmp_devices, + &num_devices, BTRFS_SUPER_INFO_OFFSET, 0); + if (ret) { + error("cannot scan %s: %s", path, strerror(-ret)); + close (fd); + continue; + } + + close(fd); + } + blkid_dev_iterate_end(iter); + blkid_put_cache(cache); + + btrfs_scan_done = 1; + + return 0; +} + +int is_vol_small(const char *file) +{ + int fd = -1; + int e; + struct stat st; + u64 size; + + fd = open(file, O_RDONLY); + if (fd < 0) + return -errno; + if (fstat(fd, &st) < 0) { + e = -errno; + close(fd); + return e; + } + size = btrfs_device_size(fd, &st); + if (size == 0) { + close(fd); + return -1; + } + if (size < BTRFS_MKFS_SMALL_VOLUME_SIZE) { + close(fd); + return 1; + } else { + close(fd); + return 0; + } +} + +/* + * This reads a line from the stdin and only returns non-zero if the + * first whitespace delimited token is a case insensitive match with yes + * or y. + */ +int ask_user(const char *question) +{ + char buf[30] = {0,}; + char *saveptr = NULL; + char *answer; + + printf("%s [y/N]: ", question); + + return fgets(buf, sizeof(buf) - 1, stdin) && + (answer = strtok_r(buf, " \t\n\r", &saveptr)) && + (!strcasecmp(answer, "yes") || !strcasecmp(answer, "y")); +} + +/* + * For a given: + * - file or directory return the containing tree root id + * - subvolume return its own tree id + * - BTRFS_EMPTY_SUBVOL_DIR_OBJECTID (directory with ino == 2) the result is + * undefined and function returns -1 + */ +int lookup_ino_rootid(int fd, u64 *rootid) +{ + struct btrfs_ioctl_ino_lookup_args args; + int ret; + + memset(&args, 0, sizeof(args)); + args.treeid = 0; + args.objectid = BTRFS_FIRST_FREE_OBJECTID; + + ret = ioctl(fd, BTRFS_IOC_INO_LOOKUP, &args); + if (ret < 0) { + error("failed to lookup root id: %s", strerror(errno)); + return ret; + } + + *rootid = args.treeid; + + return 0; +} + +/* + * return 0 if a btrfs mount point is found + * return 1 if a mount point is found but not btrfs + * return <0 if something goes wrong + */ +int find_mount_root(const char *path, char **mount_root) +{ + FILE *mnttab; + int fd; + struct mntent *ent; + int len; + int ret; + int not_btrfs = 1; + int longest_matchlen = 0; + char *longest_match = NULL; + + fd = open(path, O_RDONLY | O_NOATIME); + if (fd < 0) + return -errno; + close(fd); + + mnttab = setmntent("/proc/self/mounts", "r"); + if (!mnttab) + return -errno; + + while ((ent = getmntent(mnttab))) { + len = strlen(ent->mnt_dir); + if (strncmp(ent->mnt_dir, path, len) == 0) { + /* match found and use the latest match */ + if (longest_matchlen <= len) { + free(longest_match); + longest_matchlen = len; + longest_match = strdup(ent->mnt_dir); + not_btrfs = strcmp(ent->mnt_type, "btrfs"); + } + } + } + endmntent(mnttab); + + if (!longest_match) + return -ENOENT; + if (not_btrfs) { + free(longest_match); + return 1; + } + + ret = 0; + *mount_root = realpath(longest_match, NULL); + if (!*mount_root) + ret = -errno; + + free(longest_match); + return ret; +} + +int test_minimum_size(const char *file, u32 nodesize) +{ + int fd; + struct stat statbuf; + + fd = open(file, O_RDONLY); + if (fd < 0) + return -errno; + if (stat(file, &statbuf) < 0) { + close(fd); + return -errno; + } + if (btrfs_device_size(fd, &statbuf) < btrfs_min_dev_size(nodesize)) { + close(fd); + return 1; + } + close(fd); + return 0; +} + + +/* + * Test if path is a directory + * Returns: + * 0 - path exists but it is not a directory + * 1 - path exists and it is a directory + * < 0 - error + */ +int test_isdir(const char *path) +{ + struct stat st; + int ret; + + ret = stat(path, &st); + if (ret < 0) + return -errno; + + return !!S_ISDIR(st.st_mode); +} + +void units_set_mode(unsigned *units, unsigned mode) +{ + unsigned base = *units & UNITS_MODE_MASK; + + *units = base | mode; +} + +void units_set_base(unsigned *units, unsigned base) +{ + unsigned mode = *units & ~UNITS_MODE_MASK; + + *units = base | mode; +} + +int find_next_key(struct btrfs_path *path, struct btrfs_key *key) +{ + int level; + + for (level = 0; level < BTRFS_MAX_LEVEL; level++) { + if (!path->nodes[level]) + break; + if (path->slots[level] + 1 >= + btrfs_header_nritems(path->nodes[level])) + continue; + if (level == 0) + btrfs_item_key_to_cpu(path->nodes[level], key, + path->slots[level] + 1); + else + btrfs_node_key_to_cpu(path->nodes[level], key, + path->slots[level] + 1); + return 0; + } + return 1; +} + +const char* btrfs_group_type_str(u64 flag) +{ + u64 mask = BTRFS_BLOCK_GROUP_TYPE_MASK | + BTRFS_SPACE_INFO_GLOBAL_RSV; + + switch (flag & mask) { + case BTRFS_BLOCK_GROUP_DATA: + return "Data"; + case BTRFS_BLOCK_GROUP_SYSTEM: + return "System"; + case BTRFS_BLOCK_GROUP_METADATA: + return "Metadata"; + case BTRFS_BLOCK_GROUP_DATA|BTRFS_BLOCK_GROUP_METADATA: + return "Data+Metadata"; + case BTRFS_SPACE_INFO_GLOBAL_RSV: + return "GlobalReserve"; + default: + return "unknown"; + } +} + +const char* btrfs_group_profile_str(u64 flag) +{ + switch (flag & BTRFS_BLOCK_GROUP_PROFILE_MASK) { + case 0: + return "single"; + case BTRFS_BLOCK_GROUP_RAID0: + return "RAID0"; + case BTRFS_BLOCK_GROUP_RAID1: + return "RAID1"; + case BTRFS_BLOCK_GROUP_RAID5: + return "RAID5"; + case BTRFS_BLOCK_GROUP_RAID6: + return "RAID6"; + case BTRFS_BLOCK_GROUP_DUP: + return "DUP"; + case BTRFS_BLOCK_GROUP_RAID10: + return "RAID10"; + default: + return "unknown"; + } +} + +u64 disk_size(const char *path) +{ + struct statfs sfs; + + if (statfs(path, &sfs) < 0) + return 0; + else + return sfs.f_bsize * sfs.f_blocks; +} + +u64 get_partition_size(const char *dev) +{ + u64 result; + int fd = open(dev, O_RDONLY); + + if (fd < 0) + return 0; + if (ioctl(fd, BLKGETSIZE64, &result) < 0) { + close(fd); + return 0; + } + close(fd); + + return result; +} + +int btrfs_tree_search2_ioctl_supported(int fd) +{ + struct btrfs_ioctl_search_args_v2 *args2; + struct btrfs_ioctl_search_key *sk; + int args2_size = 1024; + char args2_buf[args2_size]; + int ret; + static int v2_supported = -1; + + if (v2_supported != -1) + return v2_supported; + + args2 = (struct btrfs_ioctl_search_args_v2 *)args2_buf; + sk = &(args2->key); + + /* + * Search for the extent tree item in the root tree. + */ + sk->tree_id = BTRFS_ROOT_TREE_OBJECTID; + sk->min_objectid = BTRFS_EXTENT_TREE_OBJECTID; + sk->max_objectid = BTRFS_EXTENT_TREE_OBJECTID; + sk->min_type = BTRFS_ROOT_ITEM_KEY; + sk->max_type = BTRFS_ROOT_ITEM_KEY; + sk->min_offset = 0; + sk->max_offset = (u64)-1; + sk->min_transid = 0; + sk->max_transid = (u64)-1; + sk->nr_items = 1; + args2->buf_size = args2_size - sizeof(struct btrfs_ioctl_search_args_v2); + ret = ioctl(fd, BTRFS_IOC_TREE_SEARCH_V2, args2); + if (ret == -EOPNOTSUPP) + v2_supported = 0; + else if (ret == 0) + v2_supported = 1; + else + return ret; + + return v2_supported; +} + +int btrfs_check_nodesize(u32 nodesize, u32 sectorsize, u64 features) +{ + if (nodesize < sectorsize) { + error("illegal nodesize %u (smaller than %u)", + nodesize, sectorsize); + return -1; + } else if (nodesize > BTRFS_MAX_METADATA_BLOCKSIZE) { + error("illegal nodesize %u (larger than %u)", + nodesize, BTRFS_MAX_METADATA_BLOCKSIZE); + return -1; + } else if (nodesize & (sectorsize - 1)) { + error("illegal nodesize %u (not aligned to %u)", + nodesize, sectorsize); + return -1; + } else if (features & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS && + nodesize != sectorsize) { + error("illegal nodesize %u (not equal to %u for mixed block group)", + nodesize, sectorsize); + return -1; + } + return 0; +} + +/* + * Copy a path argument from SRC to DEST and check the SRC length if it's at + * most PATH_MAX and fits into DEST. DESTLEN is supposed to be exact size of + * the buffer. + * The destination buffer is zero terminated. + * Return < 0 for error, 0 otherwise. + */ +int arg_copy_path(char *dest, const char *src, int destlen) +{ + size_t len = strlen(src); + + if (len >= PATH_MAX || len >= destlen) + return -ENAMETOOLONG; + + __strncpy_null(dest, src, destlen); + + return 0; +} + +unsigned int get_unit_mode_from_arg(int *argc, char *argv[], int df_mode) +{ + unsigned int unit_mode = UNITS_DEFAULT; + int arg_i; + int arg_end; + + for (arg_i = 0; arg_i < *argc; arg_i++) { + if (!strcmp(argv[arg_i], "--")) + break; + + if (!strcmp(argv[arg_i], "--raw")) { + unit_mode = UNITS_RAW; + argv[arg_i] = NULL; + continue; + } + if (!strcmp(argv[arg_i], "--human-readable")) { + unit_mode = UNITS_HUMAN_BINARY; + argv[arg_i] = NULL; + continue; + } + + if (!strcmp(argv[arg_i], "--iec")) { + units_set_mode(&unit_mode, UNITS_BINARY); + argv[arg_i] = NULL; + continue; + } + if (!strcmp(argv[arg_i], "--si")) { + units_set_mode(&unit_mode, UNITS_DECIMAL); + argv[arg_i] = NULL; + continue; + } + + if (!strcmp(argv[arg_i], "--kbytes")) { + units_set_base(&unit_mode, UNITS_KBYTES); + argv[arg_i] = NULL; + continue; + } + if (!strcmp(argv[arg_i], "--mbytes")) { + units_set_base(&unit_mode, UNITS_MBYTES); + argv[arg_i] = NULL; + continue; + } + if (!strcmp(argv[arg_i], "--gbytes")) { + units_set_base(&unit_mode, UNITS_GBYTES); + argv[arg_i] = NULL; + continue; + } + if (!strcmp(argv[arg_i], "--tbytes")) { + units_set_base(&unit_mode, UNITS_TBYTES); + argv[arg_i] = NULL; + continue; + } + + if (!df_mode) + continue; + + if (!strcmp(argv[arg_i], "-b")) { + unit_mode = UNITS_RAW; + argv[arg_i] = NULL; + continue; + } + if (!strcmp(argv[arg_i], "-h")) { + unit_mode = UNITS_HUMAN_BINARY; + argv[arg_i] = NULL; + continue; + } + if (!strcmp(argv[arg_i], "-H")) { + unit_mode = UNITS_HUMAN_DECIMAL; + argv[arg_i] = NULL; + continue; + } + if (!strcmp(argv[arg_i], "-k")) { + units_set_base(&unit_mode, UNITS_KBYTES); + argv[arg_i] = NULL; + continue; + } + if (!strcmp(argv[arg_i], "-m")) { + units_set_base(&unit_mode, UNITS_MBYTES); + argv[arg_i] = NULL; + continue; + } + if (!strcmp(argv[arg_i], "-g")) { + units_set_base(&unit_mode, UNITS_GBYTES); + argv[arg_i] = NULL; + continue; + } + if (!strcmp(argv[arg_i], "-t")) { + units_set_base(&unit_mode, UNITS_TBYTES); + argv[arg_i] = NULL; + continue; + } + } + + for (arg_i = 0, arg_end = 0; arg_i < *argc; arg_i++) { + if (!argv[arg_i]) + continue; + argv[arg_end] = argv[arg_i]; + arg_end++; + } + + *argc = arg_end; + + return unit_mode; +} + +int string_is_numerical(const char *str) +{ + if (!(*str >= '0' && *str <= '9')) + return 0; + while (*str >= '0' && *str <= '9') + str++; + if (*str != '\0') + return 0; + return 1; +} + +/* + * Preprocess @argv with getopt_long to reorder options and consume the "--" + * option separator. + * Unknown short and long options are reported, optionally the @usage is printed + * before exit. + */ +void clean_args_no_options(int argc, char *argv[], const char * const *usagestr) +{ + static const struct option long_options[] = { + {NULL, 0, NULL, 0} + }; + + while (1) { + int c = getopt_long(argc, argv, "", long_options, NULL); + + if (c < 0) + break; + + switch (c) { + default: + if (usagestr) + usage(usagestr); + } + } +} + +/* + * Same as clean_args_no_options but pass through arguments that could look + * like short options. Eg. reisze which takes a negative resize argument like + * '-123M' . + * + * This accepts only two forms: + * - "-- option1 option2 ..." + * - "option1 option2 ..." + */ +void clean_args_no_options_relaxed(int argc, char *argv[], const char * const *usagestr) +{ + if (argc <= 1) + return; + + if (strcmp(argv[1], "--") == 0) + optind = 2; +} + +/* Subvolume helper functions */ +/* + * test if name is a correct subvolume name + * this function return + * 0-> name is not a correct subvolume name + * 1-> name is a correct subvolume name + */ +int test_issubvolname(const char *name) +{ + return name[0] != '\0' && !strchr(name, '/') && + strcmp(name, ".") && strcmp(name, ".."); +} + +/* + * Test if path is a subvolume + * Returns: + * 0 - path exists but it is not a subvolume + * 1 - path exists and it is a subvolume + * < 0 - error + */ +int test_issubvolume(const char *path) +{ + struct stat st; + struct statfs stfs; + int res; + + res = stat(path, &st); + if (res < 0) + return -errno; + + if (st.st_ino != BTRFS_FIRST_FREE_OBJECTID || !S_ISDIR(st.st_mode)) + return 0; + + res = statfs(path, &stfs); + if (res < 0) + return -errno; + + return (int)stfs.f_type == BTRFS_SUPER_MAGIC; +} + +const char *subvol_strip_mountpoint(const char *mnt, const char *full_path) +{ + int len = strlen(mnt); + if (!len) + return full_path; + + if (mnt[len - 1] != '/') + len += 1; + + return full_path + len; +} + +/* + * Returns + * <0: Std error + * 0: All fine + * 1: Error; and error info printed to the terminal. Fixme. + * 2: If the fullpath is root tree instead of subvol tree + */ +int get_subvol_info(const char *fullpath, struct root_info *get_ri) +{ + u64 sv_id; + int ret = 1; + int fd = -1; + int mntfd = -1; + char *mnt = NULL; + const char *svpath = NULL; + DIR *dirstream1 = NULL; + DIR *dirstream2 = NULL; + + ret = test_issubvolume(fullpath); + if (ret < 0) + return ret; + if (!ret) { + error("not a subvolume: %s", fullpath); + return 1; + } + + ret = find_mount_root(fullpath, &mnt); + if (ret < 0) + return ret; + if (ret > 0) { + error("%s doesn't belong to btrfs mount point", fullpath); + return 1; + } + ret = 1; + svpath = subvol_strip_mountpoint(mnt, fullpath); + + fd = btrfs_open_dir(fullpath, &dirstream1, 1); + if (fd < 0) + goto out; + + ret = btrfs_list_get_path_rootid(fd, &sv_id); + if (ret) { + error("can't get rootid for '%s'", fullpath); + goto out; + } + + mntfd = btrfs_open_dir(mnt, &dirstream2, 1); + if (mntfd < 0) + goto out; + + if (sv_id == BTRFS_FS_TREE_OBJECTID) { + ret = 2; + /* + * So that caller may decide if thats an error or just fine. + */ + goto out; + } + + memset(get_ri, 0, sizeof(*get_ri)); + get_ri->root_id = sv_id; + + ret = btrfs_get_subvol(mntfd, get_ri); + if (ret) + error("can't find '%s': %d", svpath, ret); + +out: + close_file_or_dir(mntfd, dirstream2); + close_file_or_dir(fd, dirstream1); + free(mnt); + + return ret; +} + +void init_rand_seed(u64 seed) +{ + int i; + + /* only use the last 48 bits */ + for (i = 0; i < 3; i++) { + rand_seed[i] = (unsigned short)(seed ^ (unsigned short)(-1)); + seed >>= 16; + } + rand_seed_initlized = 1; +} + +static void __init_seed(void) +{ + struct timeval tv; + int ret; + int fd; + + if(rand_seed_initlized) + return; + /* Use urandom as primary seed source. */ + fd = open("/dev/urandom", O_RDONLY); + if (fd >= 0) { + ret = read(fd, rand_seed, sizeof(rand_seed)); + close(fd); + if (ret < sizeof(rand_seed)) + goto fallback; + } else { +fallback: + /* Use time and pid as fallback seed */ + warning("failed to read /dev/urandom, use time and pid as random seed"); + gettimeofday(&tv, 0); + rand_seed[0] = getpid() ^ (tv.tv_sec & 0xFFFF); + rand_seed[1] = getppid() ^ (tv.tv_usec & 0xFFFF); + rand_seed[2] = (tv.tv_sec ^ tv.tv_usec) >> 16; + } + rand_seed_initlized = 1; +} + +u32 rand_u32(void) +{ + __init_seed(); + /* + * Don't use nrand48, its range is [0,2^31) The highest bit will alwasy + * be 0. Use jrand48 to include the highest bit. + */ + return (u32)jrand48(rand_seed); +} + +unsigned int rand_range(unsigned int upper) +{ + __init_seed(); + /* + * Use the full 48bits to mod, which would be more uniformly + * distributed + */ + return (unsigned int)(jrand48(rand_seed) % upper); +} |