New upstream release.

3 files changed, 826 insertions, 37 deletions

diff --git a/mkfs/common.c b/mkfs/common.c
new file mode 100644
index 00000000..e4785c58
--- /dev/null
+++ b/mkfs/common.c
@@ -0,0 +1,729 @@
+/*
+ * 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 <unistd.h>
+#include <uuid/uuid.h>
+#include <blkid/blkid.h>
+#include <fcntl.h>
+#include <limits.h>
+#include "ctree.h"
+#include "disk-io.h"
+#include "volumes.h"
+#include "utils.h"
+#include "mkfs/common.h"
+
+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,
+};
+
+/*
+ * @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)
+{
+	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;
+
+	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) {
+		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);
+		uuid_unparse(super.fsid, cfg->fs_uuid);
+	}
+	uuid_generate(super.dev_item.uuid);
+	uuid_generate(chunk_tree_uuid);
+
+	cfg->blocks[0] = BTRFS_SUPER_INFO_OFFSET;
+	for (i = 1; i < 7; i++) {
+		cfg->blocks[i] = BTRFS_SUPER_INFO_OFFSET + 1024 * 1024 +
+			cfg->nodesize * i;
+	}
+
+	btrfs_set_super_bytenr(&super, cfg->blocks[0]);
+	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, 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);
+	super.__unused_leafsize = cpu_to_le32(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);
+
+		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;
+		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, BTRFS_STRIPE_LEN);
+	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 */
+	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;
+}
+
+u64 btrfs_min_dev_size(u32 nodesize)
+{
+	return 2 * (BTRFS_MKFS_SYSTEM_GROUP_SIZE +
+		    btrfs_min_global_blk_rsv_size(nodesize));
+}
+
+/*
+ * Btrfs minimum size calculation is complicated, it should include at least:
+ * 1. system group size
+ * 2. minimum global block reserve
+ * 3. metadata used at mkfs
+ * 4. space reservation to create uuid for first mount.
+ * Also, raid factor should also be taken into consideration.
+ * To avoid the overkill calculation, (system group + global block rsv) * 2
+ * for *EACH* device should be good enough.
+ */
+u64 btrfs_min_global_blk_rsv_size(u32 nodesize)
+{
+	return (u64)nodesize << 10;
+}
+
+#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;
+}
+
+/*
+ * 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 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;
+	}
+}
+
+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;
+}
+
+
diff --git a/mkfs/common.h b/mkfs/common.h
new file mode 100644
index 00000000..666a75b3
--- /dev/null
+++ b/mkfs/common.h
@@ -0,0 +1,63 @@
+/*
+ * 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.
+ */
+
+/*
+ * Defines and function declarations for users of the mkfs API, no internal
+ * defintions.
+ */
+
+#ifndef __BTRFS_MKFS_COMMON_H__
+#define __BTRFS_MKFS_COMMON_H__
+
+#include "kerncompat.h"
+#include "common-defs.h"
+
+#define BTRFS_MKFS_SYSTEM_GROUP_SIZE SZ_4M
+#define BTRFS_MKFS_SMALL_VOLUME_SIZE SZ_1G
+
+struct btrfs_mkfs_config {
+	/* Label of the new filesystem */
+	const char *label;
+	/* Blck sizes */
+	u32 nodesize;
+	u32 sectorsize;
+	u32 stripesize;
+	/* Bitfield of incompat features, BTRFS_FEATURE_INCOMPAT_* */
+	u64 features;
+	/* Size of the filesystem in bytes */
+	u64 num_bytes;
+
+	/* Output fields, set during creation */
+
+	/* Logical addresses of superblock [0] and other tree roots */
+	u64 blocks[8];
+	char fs_uuid[BTRFS_UUID_UNPARSED_SIZE];
+	char chunk_uuid[BTRFS_UUID_UNPARSED_SIZE];
+
+	/* Superblock offset after make_btrfs */
+	u64 super_bytenr;
+};
+
+int make_btrfs(int fd, struct btrfs_mkfs_config *cfg);
+u64 btrfs_min_dev_size(u32 nodesize);
+u64 btrfs_min_global_blk_rsv_size(u32 nodesize);
+int test_minimum_size(const char *file, u32 nodesize);
+int is_vol_small(const char *file);
+int test_num_disk_vs_raid(u64 metadata_profile, u64 data_profile,
+	u64 dev_cnt, int mixed, int ssd);
+int test_dev_for_mkfs(const char *file, int force_overwrite);
+
+#endif
diff --git a/mkfs/main.c b/mkfs/main.c
index 72834c9c..2b109a53 100644
--- a/mkfs/main.c
+++ b/mkfs/main.c
@@ -43,6 +43,9 @@
 #include "transaction.h"
 #include "utils.h"
 #include "list_sort.h"
+#include "help.h"
+#include "mkfs/common.h"
+#include "fsfeatures.h"
 
 static u64 index_cnt = 2;
 static int verbose = 1;
@@ -64,6 +67,7 @@ struct mkfs_allocation {
 static int create_metadata_block_groups(struct btrfs_root *root, int mixed,
 				struct mkfs_allocation *allocation)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct btrfs_trans_handle *trans;
 	u64 bytes_used;
 	u64 chunk_start = 0;
@@ -71,10 +75,10 @@ static int create_metadata_block_groups(struct btrfs_root *root, int mixed,
 	int ret;
 
 	trans = btrfs_start_transaction(root, 1);
-	bytes_used = btrfs_super_bytes_used(root->fs_info->super_copy);
+	bytes_used = btrfs_super_bytes_used(fs_info->super_copy);
 
 	root->fs_info->system_allocs = 1;
-	ret = btrfs_make_block_group(trans, root, bytes_used,
+	ret = btrfs_make_block_group(trans, fs_info, bytes_used,
 				     BTRFS_BLOCK_GROUP_SYSTEM,
 				     BTRFS_FIRST_CHUNK_TREE_OBJECTID,
 				     0, BTRFS_MKFS_SYSTEM_GROUP_SIZE);
@@ -83,7 +87,7 @@ static int create_metadata_block_groups(struct btrfs_root *root, int mixed,
 		return ret;
 
 	if (mixed) {
-		ret = btrfs_alloc_chunk(trans, root->fs_info->extent_root,
+		ret = btrfs_alloc_chunk(trans, fs_info,
 					&chunk_start, &chunk_size,
 					BTRFS_BLOCK_GROUP_METADATA |
 					BTRFS_BLOCK_GROUP_DATA);
@@ -93,7 +97,7 @@ static int create_metadata_block_groups(struct btrfs_root *root, int mixed,
 		}
 		if (ret)
 			return ret;
-		ret = btrfs_make_block_group(trans, root, 0,
+		ret = btrfs_make_block_group(trans, fs_info, 0,
 					     BTRFS_BLOCK_GROUP_METADATA |
 					     BTRFS_BLOCK_GROUP_DATA,
 					     BTRFS_FIRST_CHUNK_TREE_OBJECTID,
@@ -102,7 +106,7 @@ static int create_metadata_block_groups(struct btrfs_root *root, int mixed,
 			return ret;
 		allocation->mixed += chunk_size;
 	} else {
-		ret = btrfs_alloc_chunk(trans, root->fs_info->extent_root,
+		ret = btrfs_alloc_chunk(trans, fs_info,
 					&chunk_start, &chunk_size,
 					BTRFS_BLOCK_GROUP_METADATA);
 		if (ret == -ENOSPC) {
@@ -111,7 +115,7 @@ static int create_metadata_block_groups(struct btrfs_root *root, int mixed,
 		}
 		if (ret)
 			return ret;
-		ret = btrfs_make_block_group(trans, root, 0,
+		ret = btrfs_make_block_group(trans, fs_info, 0,
 					     BTRFS_BLOCK_GROUP_METADATA,
 					     BTRFS_FIRST_CHUNK_TREE_OBJECTID,
 					     chunk_start, chunk_size);
@@ -131,12 +135,13 @@ static int create_data_block_groups(struct btrfs_trans_handle *trans,
 		struct btrfs_root *root, int mixed,
 		struct mkfs_allocation *allocation)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	u64 chunk_start = 0;
 	u64 chunk_size = 0;
 	int ret = 0;
 
 	if (!mixed) {
-		ret = btrfs_alloc_chunk(trans, root->fs_info->extent_root,
+		ret = btrfs_alloc_chunk(trans, fs_info,
 					&chunk_start, &chunk_size,
 					BTRFS_BLOCK_GROUP_DATA);
 		if (ret == -ENOSPC) {
@@ -145,7 +150,7 @@ static int create_data_block_groups(struct btrfs_trans_handle *trans,
 		}
 		if (ret)
 			return ret;
-		ret = btrfs_make_block_group(trans, root, 0,
+		ret = btrfs_make_block_group(trans, fs_info, 0,
 					     BTRFS_BLOCK_GROUP_DATA,
 					     BTRFS_FIRST_CHUNK_TREE_OBJECTID,
 					     chunk_start, chunk_size);
@@ -158,8 +163,8 @@ err:
 	return ret;
 }
 
-static int make_root_dir(struct btrfs_trans_handle *trans, struct btrfs_root *root,
-		struct mkfs_allocation *allocation)
+static int make_root_dir(struct btrfs_trans_handle *trans,
+		struct btrfs_root *root)
 {
 	struct btrfs_key location;
 	int ret;
@@ -241,11 +246,12 @@ static int create_one_raid_group(struct btrfs_trans_handle *trans,
 			      struct mkfs_allocation *allocation)
 
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	u64 chunk_start;
 	u64 chunk_size;
 	int ret;
 
-	ret = btrfs_alloc_chunk(trans, root->fs_info->extent_root,
+	ret = btrfs_alloc_chunk(trans, fs_info,
 				&chunk_start, &chunk_size, type);
 	if (ret == -ENOSPC) {
 		error("not enough free space to allocate chunk");
@@ -254,7 +260,7 @@ static int create_one_raid_group(struct btrfs_trans_handle *trans,
 	if (ret)
 		return ret;
 
-	ret = btrfs_make_block_group(trans, root->fs_info->extent_root, 0,
+	ret = btrfs_make_block_group(trans, fs_info, 0,
 				     type, BTRFS_FIRST_CHUNK_TREE_OBJECTID,
 				     chunk_start, chunk_size);
 
@@ -448,7 +454,7 @@ static int fill_inode_item(struct btrfs_trans_handle *trans,
 			   struct btrfs_inode_item *dst, struct stat *src)
 {
 	u64 blocks = 0;
-	u64 sectorsize = root->sectorsize;
+	u64 sectorsize = root->fs_info->sectorsize;
 
 	/*
 	 * btrfs_inode_item has some reserved fields
@@ -541,8 +547,8 @@ static u64 calculate_dir_inode_size(const char *dirname)
 static int add_inode_items(struct btrfs_trans_handle *trans,
 			   struct btrfs_root *root,
 			   struct stat *st, const char *name,
-			   u64 self_objectid, ino_t parent_inum,
-			   int dir_index_cnt, struct btrfs_inode_item *inode_ret)
+			   u64 self_objectid,
+			   struct btrfs_inode_item *inode_ret)
 {
 	int ret;
 	struct btrfs_inode_item btrfs_inode;
@@ -642,15 +648,14 @@ fail:
 static int add_file_items(struct btrfs_trans_handle *trans,
 			  struct btrfs_root *root,
 			  struct btrfs_inode_item *btrfs_inode, u64 objectid,
-			  ino_t parent_inum, struct stat *st,
-			  const char *path_name, int out_fd)
+			  struct stat *st, const char *path_name)
 {
 	int ret = -1;
 	ssize_t ret_read;
 	u64 bytes_read = 0;
 	struct btrfs_key key;
 	int blocks;
-	u32 sectorsize = root->sectorsize;
+	u32 sectorsize = root->fs_info->sectorsize;
 	u64 first_block = 0;
 	u64 file_pos = 0;
 	u64 cur_bytes;
@@ -751,7 +756,7 @@ again:
 		if (ret)
 			goto end;
 
-		ret = write_and_map_eb(trans, root, eb);
+		ret = write_and_map_eb(root->fs_info, eb);
 		if (ret) {
 			error("failed to write %s", path_name);
 			goto end;
@@ -901,7 +906,6 @@ static int traverse_directory(struct btrfs_trans_handle *trans,
 
 			ret = add_inode_items(trans, root, &st,
 					      cur_file->d_name, cur_inum,
-					      parent_inum, dir_index_cnt,
 					      &cur_inode);
 			if (ret == -EEXIST) {
 				if (st.st_nlink <= 1) {
@@ -941,8 +945,8 @@ static int traverse_directory(struct btrfs_trans_handle *trans,
 				list_add_tail(&dir_entry->list,	&dir_head->list);
 			} else if (S_ISREG(st.st_mode)) {
 				ret = add_file_items(trans, root, &cur_inode,
-						     cur_inum, parent_inum, &st,
-						     cur_file->d_name, out_fd);
+						     cur_inum, &st,
+						     cur_file->d_name);
 				if (ret) {
 					error("unable to add file items for %s: %d",
 						cur_file->d_name, ret);
@@ -983,6 +987,7 @@ static int create_chunks(struct btrfs_trans_handle *trans,
 			 u64 size_of_data,
 			 struct mkfs_allocation *allocation)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	u64 chunk_start;
 	u64 chunk_size;
 	u64 meta_type = BTRFS_BLOCK_GROUP_METADATA;
@@ -992,35 +997,35 @@ static int create_chunks(struct btrfs_trans_handle *trans,
 	int ret;
 
 	for (i = 0; i < num_of_meta_chunks; i++) {
-		ret = btrfs_alloc_chunk(trans, root->fs_info->extent_root,
+		ret = btrfs_alloc_chunk(trans, fs_info,
 					&chunk_start, &chunk_size, meta_type);
 		if (ret)
 			return ret;
-		ret = btrfs_make_block_group(trans, root->fs_info->extent_root, 0,
+		ret = btrfs_make_block_group(trans, fs_info, 0,
 					     meta_type, BTRFS_FIRST_CHUNK_TREE_OBJECTID,
 					     chunk_start, chunk_size);
 		allocation->metadata += chunk_size;
 		if (ret)
 			return ret;
 		set_extent_dirty(&root->fs_info->free_space_cache,
-				 chunk_start, chunk_start + chunk_size - 1, 0);
+				 chunk_start, chunk_start + chunk_size - 1);
 	}
 
 	if (size_of_data < minimum_data_chunk_size)
 		size_of_data = minimum_data_chunk_size;
 
-	ret = btrfs_alloc_data_chunk(trans, root->fs_info->extent_root,
+	ret = btrfs_alloc_data_chunk(trans, fs_info,
 				     &chunk_start, size_of_data, data_type, 0);
 	if (ret)
 		return ret;
-	ret = btrfs_make_block_group(trans, root->fs_info->extent_root, 0,
+	ret = btrfs_make_block_group(trans, fs_info, 0,
 				     data_type, BTRFS_FIRST_CHUNK_TREE_OBJECTID,
 				     chunk_start, size_of_data);
 	allocation->data += size_of_data;
 	if (ret)
 		return ret;
 	set_extent_dirty(&root->fs_info->free_space_cache,
-			 chunk_start, chunk_start + size_of_data - 1, 0);
+			 chunk_start, chunk_start + size_of_data - 1);
 	return ret;
 }
 
@@ -1397,7 +1402,6 @@ int main(int argc, char **argv)
 	char *label = NULL;
 	u64 block_count = 0;
 	u64 dev_block_count = 0;
-	u64 blocks[7];
 	u64 alloc_start = 0;
 	u64 metadata_profile = 0;
 	u64 data_profile = 0;
@@ -1720,12 +1724,6 @@ int main(int argc, char **argv)
 		exit(1);
 	}
 
-	blocks[0] = BTRFS_SUPER_INFO_OFFSET;
-	for (i = 1; i < 7; i++) {
-		blocks[i] = BTRFS_SUPER_INFO_OFFSET + 1024 * 1024 +
-			nodesize * i;
-	}
-
 	if (group_profile_max_safe_loss(metadata_profile) <
 		group_profile_max_safe_loss(data_profile)){
 		warning("metadata has lower redundancy than data!\n");
@@ -1733,7 +1731,6 @@ int main(int argc, char **argv)
 
 	mkfs_cfg.label = label;
 	memcpy(mkfs_cfg.fs_uuid, fs_uuid, sizeof(mkfs_cfg.fs_uuid));
-	memcpy(mkfs_cfg.blocks, blocks, sizeof(blocks));
 	mkfs_cfg.num_bytes = dev_block_count;
 	mkfs_cfg.nodesize = nodesize;
 	mkfs_cfg.sectorsize = sectorsize;
@@ -1774,7 +1771,7 @@ int main(int argc, char **argv)
 		exit(1);
 	}
 
-	ret = make_root_dir(trans, root, &allocation);
+	ret = make_root_dir(trans, root);
 	if (ret) {
 		error("failed to setup the root directory: %d", ret);
 		exit(1);