#include <sys/statfs.h>
#include <linux/magic.h>
#include <getopt.h>
+#include <sys/utsname.h>
+#include <linux/version.h>
#include "kerncompat.h"
#include "radix-tree.h"
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;
{
u64 range[2] = { start, len };
- if (ioctl(fd, BLKDISCARD, &range) < 0)
- return errno;
- return 0;
+ 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;
+
+ ASSERT(ret_start != NULL);
+ 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, &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.
+ *
+ * The superblock signature is not valid, denotes a partially created
+ * filesystem, needs to be finalized.
+ */
+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;
+
+ memset(super_buf, 0, BTRFS_SUPER_INFO_SIZE);
+ cfg->num_bytes = round_down(cfg->num_bytes, cfg->sectorsize);
+
+ if (*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_PARTIAL);
+ 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;
+
+ 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.
+ */
+ if (!(root_bytenr < extent_bytenr && extent_bytenr < dev_bytenr &&
+ dev_bytenr < fs_bytenr && fs_bytenr < csum_bytenr)) {
+ error("bad tree bytenr order: "
+ "root < extent %llu < %llu, "
+ "extent < dev %llu < %llu, "
+ "dev < fs %llu < %llu, "
+ "fs < csum %llu < %llu",
+ (unsigned long long)root_bytenr,
+ (unsigned long long)extent_bytenr,
+ (unsigned long long)extent_bytenr,
+ (unsigned long long)dev_bytenr,
+ (unsigned long long)dev_bytenr,
+ (unsigned long long)fs_bytenr,
+ (unsigned long long)fs_bytenr,
+ (unsigned long long)csum_bytenr);
+ return -EINVAL;
+ }
+ 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 */
+ if (meta_chunk_start < sys_chunk_start) {
+ error("wrong chunk order: meta < system %llu < %llu",
+ (unsigned long long)meta_chunk_start,
+ (unsigned long long)sys_chunk_start);
+ return -EINVAL;
+ }
+ 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 */
+ if (meta_chunk_start < sys_chunk_start) {
+ error("wrong chunk order: meta < system %llu < %llu",
+ (unsigned long long)meta_chunk_start,
+ (unsigned long long)sys_chunk_start);
+ return -EINVAL;
+ }
+ 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.
+ */
+ if (!(chunk_bytenr < root_bytenr && root_bytenr < extent_bytenr &&
+ extent_bytenr < dev_bytenr && dev_bytenr < fs_bytenr &&
+ fs_bytenr < csum_bytenr)) {
+ error("bad tree bytenr order: "
+ "chunk < root %llu < %llu, "
+ "root < extent %llu < %llu, "
+ "extent < dev %llu < %llu, "
+ "dev < fs %llu < %llu, "
+ "fs < csum %llu < %llu",
+ (unsigned long long)chunk_bytenr,
+ (unsigned long long)root_bytenr,
+ (unsigned long long)root_bytenr,
+ (unsigned long long)extent_bytenr,
+ (unsigned long long)extent_bytenr,
+ (unsigned long long)dev_bytenr,
+ (unsigned long long)dev_bytenr,
+ (unsigned long long)fs_bytenr,
+ (unsigned long long)fs_bytenr,
+ (unsigned long long)csum_bytenr);
+ return -EINVAL;
+ }
+ 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;
}
/*
- * Discard blocks in the given range in 1G chunks, the process is interruptible
+ * 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 discard_blocks(int fd, u64 start, u64 len)
+static int make_convert_btrfs(int fd, struct btrfs_mkfs_config *cfg,
+ struct btrfs_convert_context *cctx)
{
- 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,
-};
+ 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;
-int test_uuid_unique(char *fs_uuid)
-{
- int unique = 1;
- blkid_dev_iterate iter = NULL;
- blkid_dev dev = NULL;
- blkid_cache cache = NULL;
+ /* Shouldn't happen */
+ BUG_ON(cache_tree_empty(used));
- 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);
+ /*
+ * 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;
- while (blkid_dev_next(iter, &dev) == 0) {
- dev = blkid_verify(cache, dev);
- if (dev) {
- unique = 0;
- break;
- }
- }
+ /*
+ * 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;
- blkid_dev_iterate_end(iter);
- blkid_put_cache(cache);
+ /*
+ * 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;
- return unique;
+ 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
+ *
+ * The superblock signature is not valid, denotes a partially created
+ * filesystem, needs to be finalized.
*/
-int make_btrfs(int fd, struct btrfs_mkfs_config *cfg)
+int make_btrfs(int fd, struct btrfs_mkfs_config *cfg,
+ struct btrfs_convert_context *cctx)
{
struct btrfs_super_block super;
struct extent_buffer *buf;
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;
memset(&super, 0, sizeof(super));
num_bytes = (cfg->num_bytes / cfg->sectorsize) * cfg->sectorsize;
- if (cfg->fs_uuid && *cfg->fs_uuid) {
+ if (*cfg->fs_uuid) {
if (uuid_parse(cfg->fs_uuid, super.fsid) != 0) {
- fprintf(stderr, "could not parse UUID: %s\n",
- cfg->fs_uuid);
+ error("cannot not parse UUID: %s", cfg->fs_uuid);
ret = -EINVAL;
goto out;
}
if (!test_uuid_unique(cfg->fs_uuid)) {
- fprintf(stderr, "non-unique UUID: %s\n", 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_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_magic(&super, BTRFS_MAGIC_PARTIAL);
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_cache_generation(&super, -1);
btrfs_set_super_incompat_flags(&super, cfg->features);
if (cfg->label)
- strncpy(super.label, cfg->label, BTRFS_LABEL_SIZE - 1);
+ __strncpy_null(super.label, cfg->label, BTRFS_LABEL_SIZE - 1);
/* create the tree of root objects */
memset(buf->data, 0, cfg->nodesize);
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]);
+ if (cfg->blocks[i] < first_free) {
+ error("block[%d] below first free: %llu < %llu",
+ i, (unsigned long long)cfg->blocks[i],
+ (unsigned long long)first_free);
+ ret = -EINVAL;
+ goto out;
+ }
+ if (cfg->blocks[i] < cfg->blocks[i - 1]) {
+ error("blocks %d and %d in reverse order: %llu < %llu",
+ i, i - 1,
+ (unsigned long long)cfg->blocks[i],
+ (unsigned long long)cfg->blocks[i - 1]);
+ ret = -EINVAL;
+ goto out;
+ }
/* create extent item */
itemoff -= item_size;
}
/* 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;
return ret;
}
+#define VERSION_TO_STRING3(a,b,c) #a "." #b "." #c, KERNEL_VERSION(a,b,c)
+#define VERSION_TO_STRING2(a,b) #a "." #b, KERNEL_VERSION(a,b,0)
+
+/*
+ * Feature stability status and versions: compat <= safe <= default
+ */
static const struct btrfs_fs_feature {
const char *name;
u64 flag;
+ const char *sysfs_name;
+ /*
+ * Compatibility with kernel of given version. Filesystem can be
+ * mounted.
+ */
+ const char *compat_str;
+ u32 compat_ver;
+ /*
+ * Considered safe for use, but is not on by default, even if the
+ * kernel supports the feature.
+ */
+ const char *safe_str;
+ u32 safe_ver;
+ /*
+ * Considered safe for use and will be turned on by default if
+ * supported by the running kernel.
+ */
+ const char *default_str;
+ u32 default_ver;
const char *desc;
} mkfs_features[] = {
{ "mixed-bg", BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS,
+ "mixed_groups",
+ VERSION_TO_STRING3(2,6,37),
+ VERSION_TO_STRING3(2,6,37),
+ NULL, 0,
"mixed data and metadata block groups" },
{ "extref", BTRFS_FEATURE_INCOMPAT_EXTENDED_IREF,
+ "extended_iref",
+ VERSION_TO_STRING2(3,7),
+ VERSION_TO_STRING2(3,12),
+ VERSION_TO_STRING2(3,12),
"increased hardlink limit per file to 65536" },
{ "raid56", BTRFS_FEATURE_INCOMPAT_RAID56,
+ "raid56",
+ VERSION_TO_STRING2(3,9),
+ NULL, 0,
+ NULL, 0,
"raid56 extended format" },
{ "skinny-metadata", BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA,
+ "skinny_metadata",
+ VERSION_TO_STRING2(3,10),
+ VERSION_TO_STRING2(3,18),
+ VERSION_TO_STRING2(3,18),
"reduced-size metadata extent refs" },
{ "no-holes", BTRFS_FEATURE_INCOMPAT_NO_HOLES,
+ "no_holes",
+ VERSION_TO_STRING2(3,14),
+ VERSION_TO_STRING2(4,0),
+ NULL, 0,
"no explicit hole extents for files" },
/* Keep this one last */
{ "list-all", BTRFS_FEATURE_LIST_ALL, NULL }
fprintf(stderr, "Filesystem features available:\n");
for (i = 0; i < ARRAY_SIZE(mkfs_features) - 1; i++) {
- char *is_default = "";
+ const struct btrfs_fs_feature *feat = &mkfs_features[i];
- if (mkfs_features[i].flag & mask_disallowed)
+ if (feat->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);
+ fprintf(stderr, "%-20s- %s (0x%llx", feat->name, feat->desc,
+ feat->flag);
+ if (feat->compat_ver)
+ fprintf(stderr, ", compat=%s", feat->compat_str);
+ if (feat->safe_ver)
+ fprintf(stderr, ", safe=%s", feat->safe_str);
+ if (feat->default_ver)
+ fprintf(stderr, ", default=%s", feat->default_str);
+ fprintf(stderr, ")\n");
}
}
return NULL;
}
+void print_kernel_version(FILE *stream, u32 version)
+{
+ u32 v[3];
+
+ v[0] = version & 0xFF;
+ v[1] = (version >> 8) & 0xFF;
+ v[2] = version >> 16;
+ fprintf(stream, "%u.%u", v[2], v[1]);
+ if (v[0])
+ fprintf(stream, ".%u", v[0]);
+}
+
+u32 get_running_kernel_version(void)
+{
+ struct utsname utsbuf;
+ char *tmp;
+ char *saveptr = NULL;
+ u32 version;
+
+ uname(&utsbuf);
+ if (strcmp(utsbuf.sysname, "Linux") != 0) {
+ error("unsupported system: %s", utsbuf.sysname);
+ exit(1);
+ }
+ /* 1.2.3-4-name */
+ tmp = strchr(utsbuf.release, '-');
+ if (tmp)
+ *tmp = 0;
+
+ tmp = strtok_r(utsbuf.release, ".", &saveptr);
+ if (!string_is_numerical(tmp))
+ return (u32)-1;
+ version = atoi(tmp) << 16;
+ tmp = strtok_r(NULL, ".", &saveptr);
+ if (!string_is_numerical(tmp))
+ return (u32)-1;
+ version |= atoi(tmp) << 8;
+ tmp = strtok_r(NULL, ".", &saveptr);
+ if (tmp) {
+ if (!string_is_numerical(tmp))
+ return (u32)-1;
+ version |= atoi(tmp);
+ }
+
+ return version;
+}
+
u64 btrfs_device_size(int fd, struct stat *st)
{
u64 size;
}
int btrfs_add_to_fsid(struct btrfs_trans_handle *trans,
- struct btrfs_root *root, int fd, char *path,
+ struct btrfs_root *root, int fd, const char *path,
u64 device_total_bytes, u32 io_width, u32 io_align,
u32 sectorsize)
{
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);
+ device = calloc(1, sizeof(*device));
+ if (!device) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ buf = calloc(1, sectorsize);
+ if (!buf) {
+ ret = -ENOMEM;
+ goto out;
+ }
disk_super = (struct btrfs_super_block *)buf;
dev_item = &disk_super->dev_item;
device->total_ios = 0;
device->dev_root = root->fs_info->dev_root;
device->name = strdup(path);
- if (!device->name)
- goto err_nomem;
+ if (!device->name) {
+ ret = -ENOMEM;
+ goto out;
+ }
INIT_LIST_HEAD(&device->dev_list);
ret = btrfs_add_device(trans, root, device);
- BUG_ON(ret);
+ if (ret)
+ goto out;
fs_total_bytes = btrfs_super_total_bytes(super) + device_total_bytes;
btrfs_set_super_total_bytes(super, fs_total_bytes);
ret = pwrite(fd, buf, sectorsize, BTRFS_SUPER_INFO_OFFSET);
BUG_ON(ret != sectorsize);
- kfree(buf);
+ free(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;
+out:
+ free(device);
+ free(buf);
+ return ret;
}
static int btrfs_wipe_existing_sb(int fd)
return ret;
}
-int btrfs_prepare_device(int fd, char *file, int zero_end, u64 *block_count_ret,
- u64 max_block_count, int discard)
+int btrfs_prepare_device(int fd, const char *file, u64 *block_count_ret,
+ u64 max_block_count, unsigned opflags)
{
u64 block_count;
struct stat st;
if (max_block_count)
block_count = min(block_count, max_block_count);
- if (discard) {
+ if (opflags & PREP_DEVICE_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));
+ if (opflags & PREP_DEVICE_VERBOSE)
+ printf("Performing full device TRIM (%s) ...\n",
+ pretty_size(block_count));
discard_blocks(fd, 0, 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)
+ if (!ret && (opflags & PREP_DEVICE_ZERO_END))
ret = zero_dev_clamped(fd, block_count - ZERO_DEV_BYTES,
ZERO_DEV_BYTES, block_count);
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_sec(&inode_item.otime, now);
btrfs_set_stack_timespec_nsec(&inode_item.otime, 0);
if (root->fs_info->tree_root == root)
/* scan the initial device */
ret = btrfs_scan_one_device(fd, file, &fs_devices_mnt,
- &total_devs, BTRFS_SUPER_INFO_OFFSET, 0);
+ &total_devs, BTRFS_SUPER_INFO_OFFSET, SBREAD_DEFAULT);
is_btrfs = (ret >= 0);
/* scan other devices */
if (is_btrfs && total_devs > 1) {
- ret = btrfs_scan_lblkid();
+ ret = btrfs_scan_devices();
if (ret)
return ret;
}
- /* iterate over the list of currently mountes filesystems */
+ /* iterate over the list of currently mounted filesystems */
if ((f = setmntent ("/proc/self/mounts", "r")) == NULL)
return -errno;
/*
* Register all devices in the fs_uuid list created in the user
- * space. Ensure btrfs_scan_lblkid() is called before this func.
+ * space. Ensure btrfs_scan_devices() is called before this func.
*/
int btrfs_register_all_devices(void)
{
ret = 0;
disk_super = (struct btrfs_super_block *)buf;
- if (btrfs_super_magic(disk_super) != BTRFS_MAGIC)
+ /*
+ * Accept devices from the same filesystem, allow partially created
+ * structures.
+ */
+ if (btrfs_super_magic(disk_super) != BTRFS_MAGIC &&
+ btrfs_super_magic(disk_super) != BTRFS_MAGIC_PARTIAL)
goto brelse;
if (!memcmp(disk_super->fsid, root->fs_info->super_copy->fsid,
}
/*
- * __strncpy__null - strncpy with null termination
+ * __strncpy_null - strncpy with null termination
* @dest: the target array
* @src: the source string
* @n: maximum bytes to copy (size of *dest)
* 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)
+char *__strncpy_null(char *dest, const char *src, size_t n)
{
strncpy(dest, src, n);
if (n > 0)
int len = strlen(input);
if (len > BTRFS_LABEL_SIZE - 1) {
- fprintf(stderr, "ERROR: Label %s is too long (max %d)\n",
- input, BTRFS_LABEL_SIZE - 1);
+ error("label %s is too long (max %d)", input,
+ BTRFS_LABEL_SIZE - 1);
return -1;
}
ret = check_mounted(dev);
if (ret < 0) {
- fprintf(stderr, "FATAL: error checking %s mount status\n", dev);
+ error("checking mount status of %s failed: %d", dev, ret);
return -1;
}
if (ret > 0) {
- fprintf(stderr, "ERROR: dev %s is mounted, use mount point\n",
- dev);
+ error("device %s is mounted, use mount point", dev);
return -1;
}
return -1;
trans = btrfs_start_transaction(root, 1);
- snprintf(root->fs_info->super_copy->label, BTRFS_LABEL_SIZE, "%s",
- label);
+ __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. */
fd = open(mount_path, O_RDONLY | O_NOATIME);
if (fd < 0) {
- fprintf(stderr, "ERROR: unable to access '%s'\n", mount_path);
+ error("unable to access %s: %s", mount_path, strerror(errno));
return -1;
}
memset(label, 0, sizeof(label));
- strncpy(label, labelp, sizeof(label));
+ __strncpy_null(label, labelp, BTRFS_LABEL_SIZE - 1);
if (ioctl(fd, BTRFS_IOC_SET_FSLABEL, label) < 0) {
- fprintf(stderr, "ERROR: unable to set label %s\n",
- strerror(errno));
+ error("unable to set label of %s: %s", mount_path,
+ strerror(errno));
close(fd);
return -1;
}
ret = check_mounted(dev);
if (ret < 0) {
- fprintf(stderr, "FATAL: error checking %s mount status\n", dev);
+ error("checking mount status of %s failed: %d", dev, ret);
return -1;
}
if(!root)
return -1;
- memcpy(label, root->fs_info->super_copy->label, BTRFS_LABEL_SIZE);
+ __strncpy_null(label, root->fs_info->super_copy->label,
+ BTRFS_LABEL_SIZE - 1);
/* Now we close it since we are done. */
close_ctree(root);
fd = open(mount_path, O_RDONLY | O_NOATIME);
if (fd < 0) {
- fprintf(stderr, "ERROR: unable to access '%s'\n", mount_path);
+ error("unable to access %s: %s", mount_path, strerror(errno));
return -1;
}
ret = ioctl(fd, BTRFS_IOC_GET_FSLABEL, label);
if (ret < 0) {
if (errno != ENOTTY)
- fprintf(stderr, "ERROR: unable to get label %s\n",
+ error("unable to get label of %s: %s", mount_path,
strerror(errno));
ret = -errno;
close(fd);
return ret;
}
- strncpy(labelp, label, sizeof(label));
+ __strncpy_null(labelp, label, BTRFS_LABEL_SIZE - 1);
close(fd);
return 0;
}
u64 ret;
if (!s) {
- fprintf(stderr, "ERROR: Size value is empty\n");
+ error("size value is empty");
exit(1);
}
if (s[0] == '-') {
- fprintf(stderr,
- "ERROR: Size value '%s' is less equal than 0\n", s);
+ error("size value '%s' is less equal than 0", s);
exit(1);
}
ret = strtoull(s, &endptr, 10);
if (endptr == s) {
- fprintf(stderr, "ERROR: Size value '%s' is invalid\n", s);
+ error("size value '%s' is invalid", s);
exit(1);
}
if (endptr[0] && endptr[1]) {
- fprintf(stderr, "ERROR: Illegal suffix contains character '%c' in wrong position\n",
+ error("illegal suffix contains character '%c' in wrong position",
endptr[1]);
exit(1);
}
* need to call strtoull to get the real size
*/
if (errno == ERANGE && ret == ULLONG_MAX) {
- fprintf(stderr,
- "ERROR: Size value '%s' is too large for u64\n", s);
+ error("size value '%s' is too large for u64", s);
exit(1);
}
if (endptr[0]) {
case 'b':
break;
default:
- fprintf(stderr, "ERROR: Unknown size descriptor '%c'\n",
- c);
+ error("unknown size descriptor '%c'", c);
exit(1);
}
}
/* Check whether ret * mult overflow */
if (fls64(ret) + fls64(mult) - 1 > 64) {
- fprintf(stderr,
- "ERROR: Size value '%s' is too large for u64\n", s);
+ error("size value '%s' is too large for u64", s);
exit(1);
}
ret *= mult;
fd = open(p, O_RDONLY);
if (fd < 0)
goto err;
- ret = lookup_ino_rootid(fd, &id);
+ ret = lookup_path_rootid(fd, &id);
+ if (ret)
+ error("failed to lookup root id: %s", strerror(-ret));
close(fd);
if (ret < 0)
goto err;
return id;
err:
- fprintf(stderr, "ERROR: invalid qgroupid or subvolume path: %s\n", p);
+ error("invalid qgroupid or subvolume path: %s", p);
exit(-1);
}
*
* Returns 0 on success, or a negative errno.
*/
-int get_fs_info(char *path, struct btrfs_ioctl_fs_info_args *fi_args,
+int get_fs_info(const 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;
+ u64 last_devid = 0;
int replacing = 0;
struct btrfs_fs_devices *fs_devices_mnt = NULL;
struct btrfs_ioctl_dev_info_args *di_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);
ret = -EIO;
goto out;
}
- devid = btrfs_stack_device_id(&disk_super->dev_item);
-
- fi_args->max_id = devid;
- i = devid;
+ last_devid = btrfs_stack_device_id(&disk_super->dev_item);
+ fi_args->max_id = last_devid;
memcpy(fi_args->fsid, fs_devices_mnt->fsid, BTRFS_FSID_SIZE);
close(fd);
fi_args->num_devices++;
ndevs++;
replacing = 1;
- if (i == 0)
- i++;
+ if (last_devid == 0)
+ last_devid++;
}
}
if (replacing)
memcpy(di_args, &tmp, sizeof(tmp));
- for (; i <= fi_args->max_id; ++i) {
- ret = get_device_info(fd, i, &di_args[ndevs]);
+ for (; last_devid <= fi_args->max_id; last_devid++) {
+ ret = get_device_info(fd, last_devid, &di_args[ndevs]);
if (ret == -ENODEV)
continue;
if (ret)
* 0 for nothing found
* -1 for internal error
*/
-static int
-check_overwrite(
- char *device)
+static int check_overwrite(const char *device)
{
const char *type;
blkid_probe pr = NULL;
u64 dev_cnt, int mixed, int ssd)
{
u64 allowed = 0;
+ u64 profile = metadata_profile | data_profile;
switch (dev_cnt) {
default:
case 2:
allowed |= BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1 |
BTRFS_BLOCK_GROUP_RAID5;
- break;
case 1:
allowed |= BTRFS_BLOCK_GROUP_DUP;
}
- if (dev_cnt > 1 &&
- ((metadata_profile | data_profile) & BTRFS_BLOCK_GROUP_DUP)) {
- fprintf(stderr,
- "ERROR: DUP is not allowed when FS has multiple devices\n");
- return 1;
+ if (dev_cnt > 1 && profile & BTRFS_BLOCK_GROUP_DUP) {
+ warning("DUP is not recommended on filesystem with multiple devices");
}
if (metadata_profile & ~allowed) {
fprintf(stderr,
return 1;
}
+ if (dev_cnt == 3 && profile & BTRFS_BLOCK_GROUP_RAID6) {
+ warning("RAID6 is not recommended on filesystem with 3 devices only");
+ }
+ if (dev_cnt == 2 && profile & BTRFS_BLOCK_GROUP_RAID5) {
+ warning("RAID5 is not recommended on filesystem with 2 devices only");
+ }
warning_on(!mixed && (data_profile & BTRFS_BLOCK_GROUP_DUP) && ssd,
"DUP may not actually lead to 2 copies on the device, see manual page");
* 1: something is wrong, an error is printed
* 0: all is fine
*/
-int test_dev_for_mkfs(char *file, int force_overwrite)
+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) {
- fprintf(stderr, "ERROR: checking status of %s: %s\n", file,
- strerror(-ret));
+ error("checking status of %s: %s", file, strerror(-ret));
return 1;
}
if (ret == 1) {
- fprintf(stderr, "ERROR: %s is a swap device\n", file);
+ error("%s is a swap device", file);
return 1;
}
if (!force_overwrite) {
if (check_overwrite(file)) {
- fprintf(stderr, "Use the -f option to force overwrite.\n");
+ error("use the -f option to force overwrite of %s",
+ file);
return 1;
}
}
ret = check_mounted(file);
if (ret < 0) {
- fprintf(stderr, "ERROR: checking mount status of %s: %s\n",
- file, strerror(-ret));
+ error("cannot check mount status of %s: %s", file,
+ strerror(-ret));
return 1;
}
if (ret == 1) {
- fprintf(stderr, "ERROR: %s is mounted\n", file);
+ error("%s is mounted", file);
return 1;
}
/* check if the device is busy */
fd = open(file, O_RDWR|O_EXCL);
if (fd < 0) {
- fprintf(stderr, "ERROR: unable to open %s: %s\n", file,
- strerror(errno));
+ error("unable to open %s: %s", file, strerror(errno));
return 1;
}
if (fstat(fd, &st)) {
- fprintf(stderr, "ERROR: unable to stat %s: %s\n", file,
- strerror(errno));
+ error("unable to stat %s: %s", file, strerror(errno));
close(fd);
return 1;
}
if (!S_ISBLK(st.st_mode)) {
- fprintf(stderr, "ERROR: %s is not a block device\n", file);
+ error("%s is not a block device", file);
close(fd);
return 1;
}
return 0;
}
-int btrfs_scan_lblkid(void)
+int btrfs_scan_devices(void)
{
int fd = -1;
int ret;
return 0;
if (blkid_get_cache(&cache, NULL) < 0) {
- printf("ERROR: lblkid cache get failed\n");
+ error("blkid cache get failed");
return 1;
}
blkid_probe_all(cache);
fd = open(path, O_RDONLY);
if (fd < 0) {
- printf("ERROR: could not open %s\n", path);
+ 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);
+ &num_devices, BTRFS_SUPER_INFO_OFFSET,
+ SBREAD_DEFAULT);
if (ret) {
- printf("ERROR: could not scan %s\n", path);
+ error("cannot scan %s: %s", path, strerror(-ret));
close (fd);
continue;
}
return 0;
}
-int is_vol_small(char *file)
+int is_vol_small(const char *file)
{
int fd = -1;
int e;
* first whitespace delimited token is a case insensitive match with yes
* or y.
*/
-int ask_user(char *question)
+int ask_user(const char *question)
{
char buf[30] = {0,};
char *saveptr = NULL;
}
/*
- * 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) {
- fprintf(stderr, "ERROR: Failed to lookup root id - %s\n",
- 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
return 1;
}
-char* btrfs_group_type_str(u64 flag)
+const char* btrfs_group_type_str(u64 flag)
{
u64 mask = BTRFS_BLOCK_GROUP_TYPE_MASK |
BTRFS_SPACE_INFO_GLOBAL_RSV;
}
}
-char* btrfs_group_profile_str(u64 flag)
+const char* btrfs_group_profile_str(u64 flag)
{
switch (flag & BTRFS_BLOCK_GROUP_PROFILE_MASK) {
case 0:
}
}
-u64 disk_size(char *path)
+u64 disk_size(const char *path)
{
struct statfs sfs;
return sfs.f_bsize * sfs.f_blocks;
}
-u64 get_partition_size(char *dev)
+u64 get_partition_size(const char *dev)
{
u64 result;
int fd = open(dev, O_RDONLY);
return result;
}
+/*
+ * Check if the BTRFS_IOC_TREE_SEARCH_V2 ioctl is supported on a given
+ * filesystem, opened at fd
+ */
int btrfs_tree_search2_ioctl_supported(int fd)
{
struct btrfs_ioctl_search_args_v2 *args2;
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);
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;
+ return 0;
else if (ret == 0)
- v2_supported = 1;
- else
- return ret;
-
- return v2_supported;
+ return 1;
+ return ret;
}
int btrfs_check_nodesize(u32 nodesize, u32 sectorsize, u64 features)
{
if (nodesize < sectorsize) {
- fprintf(stderr,
- "ERROR: Illegal nodesize %u (smaller than %u)\n",
- nodesize, sectorsize);
+ error("illegal nodesize %u (smaller than %u)",
+ nodesize, sectorsize);
return -1;
} else if (nodesize > BTRFS_MAX_METADATA_BLOCKSIZE) {
- fprintf(stderr,
- "ERROR: Illegal nodesize %u (larger than %u)\n",
+ error("illegal nodesize %u (larger than %u)",
nodesize, BTRFS_MAX_METADATA_BLOCKSIZE);
return -1;
} else if (nodesize & (sectorsize - 1)) {
- fprintf(stderr,
- "ERROR: Illegal nodesize %u (not aligned to %u)\n",
+ error("illegal nodesize %u (not aligned to %u)",
nodesize, sectorsize);
return -1;
} else if (features & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS &&
nodesize != sectorsize) {
- fprintf(stderr,
- "ERROR: Illegal nodesize %u (not equal to %u for mixed block group)\n",
+ error("illegal nodesize %u (not equal to %u for mixed block group)",
nodesize, sectorsize);
return -1;
}
if (len >= PATH_MAX || len >= destlen)
return -ENAMETOOLONG;
- __strncpy__null(dest, src, destlen);
+ __strncpy_null(dest, src, destlen);
return 0;
}
int string_is_numerical(const char *str)
{
+ if (!str)
+ return 0;
if (!(*str >= '0' && *str <= '9'))
return 0;
while (*str >= '0' && *str <= '9')
}
}
+/*
+ * 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
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)
+ goto out;
+
+ mntfd = btrfs_open_dir(mnt, &dirstream2, 1);
+ if (mntfd < 0)
+ goto out;
+
+ memset(get_ri, 0, sizeof(*get_ri));
+ get_ri->root_id = sv_id;
+
+ if (sv_id == BTRFS_FS_TREE_OBJECTID)
+ ret = btrfs_get_toplevel_subvol(mntfd, get_ri);
+ else
+ 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);
+}