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btrfs-progs/mkfs/common.c

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/*
* 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 "kernel-shared/ctree.h"
#include "kernel-shared/disk-io.h"
#include "kernel-shared/volumes.h"
#include "kernel-shared/transaction.h"
#include "kernel-shared/zoned.h"
#include "common/utils.h"
#include "common/path-utils.h"
#include "common/device-utils.h"
#include "common/open-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,
};
static int btrfs_create_tree_root(int fd, struct btrfs_mkfs_config *cfg,
struct extent_buffer *buf)
{
struct btrfs_root_item root_item;
struct btrfs_inode_item *inode_item;
struct btrfs_disk_key disk_key;
u32 nritems = 0;
u32 itemoff;
int ret = 0;
int blk;
u8 uuid[BTRFS_UUID_SIZE];
memset(buf->data + sizeof(struct btrfs_header), 0,
cfg->nodesize - sizeof(struct btrfs_header));
memset(&root_item, 0, sizeof(root_item));
memset(&disk_key, 0, sizeof(disk_key));
/* create the items for the root tree */
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_disk_key_type(&disk_key, BTRFS_ROOT_ITEM_KEY);
btrfs_set_disk_key_offset(&disk_key, 0);
itemoff = __BTRFS_LEAF_DATA_SIZE(cfg->nodesize) - sizeof(root_item);
for (blk = 0; blk < MKFS_BLOCK_COUNT; blk++) {
if (blk == MKFS_SUPER_BLOCK || blk == MKFS_ROOT_TREE
|| blk == MKFS_CHUNK_TREE)
continue;
btrfs_set_root_bytenr(&root_item, cfg->blocks[blk]);
btrfs_set_disk_key_objectid(&disk_key,
reference_root_table[blk]);
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));
if (blk == MKFS_FS_TREE) {
time_t now = time(NULL);
uuid_generate(uuid);
memcpy(root_item.uuid, uuid, BTRFS_UUID_SIZE);
btrfs_set_stack_timespec_sec(&root_item.otime, now);
btrfs_set_stack_timespec_sec(&root_item.ctime, now);
} else {
memset(uuid, 0, BTRFS_UUID_SIZE);
memcpy(root_item.uuid, uuid, BTRFS_UUID_SIZE);
btrfs_set_stack_timespec_sec(&root_item.otime, 0);
btrfs_set_stack_timespec_sec(&root_item.ctime, 0);
}
write_extent_buffer(buf, &root_item,
btrfs_item_ptr_offset(buf, nritems),
sizeof(root_item));
nritems++;
itemoff -= sizeof(root_item);
}
/* generate checksum */
csum_tree_block_size(buf, btrfs_csum_type_size(cfg->csum_type), 0,
cfg->csum_type);
/* write back root tree */
ret = pwrite(fd, buf->data, cfg->nodesize, cfg->blocks[MKFS_ROOT_TREE]);
if (ret != cfg->nodesize)
return (ret < 0 ? -errno : -EIO);
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.
*
* The temporary fs will have the following chunk layout:
* Device extent:
* 0 1M 5M ......
* | Reserved | dev extent for SYS chunk |
*
* And chunk mapping will be:
* Chunk mapping:
* 0 1M 5M
* | | System chunk, 1:1 mapped |
*
* That's to say, there will only be *ONE* system chunk, mapped to
* [1M, 5M) physical offset.
* And the only chunk is also in logical address [1M, 5M), containing
* all essential tree blocks.
*/
int make_btrfs(int fd, struct btrfs_mkfs_config *cfg)
{
struct btrfs_super_block super;
struct extent_buffer *buf;
struct btrfs_disk_key disk_key;
struct btrfs_extent_item *extent_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;
u64 system_group_offset = BTRFS_BLOCK_RESERVED_1M_FOR_SUPER;
u64 system_group_size = BTRFS_MKFS_SYSTEM_GROUP_SIZE;
if ((cfg->features & BTRFS_FEATURE_INCOMPAT_ZONED)) {
system_group_offset = cfg->zone_size * BTRFS_NR_SB_LOG_ZONES;
system_group_size = cfg->zone_size;
}
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[MKFS_SUPER_BLOCK] = BTRFS_SUPER_INFO_OFFSET;
for (i = 1; i < MKFS_BLOCK_COUNT; i++) {
cfg->blocks[i] = system_group_offset + cfg->nodesize * (i - 1);
}
btrfs_set_super_bytenr(&super, cfg->blocks[MKFS_SUPER_BLOCK]);
btrfs_set_super_num_devices(&super, 1);
btrfs_set_super_magic(&super, BTRFS_MAGIC_TEMPORARY);
btrfs_set_super_generation(&super, 1);
btrfs_set_super_root(&super, cfg->blocks[MKFS_ROOT_TREE]);
btrfs_set_super_chunk_root(&super, cfg->blocks[MKFS_CHUNK_TREE]);
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, cfg->csum_type);
btrfs_set_super_chunk_root_generation(&super, 1);
if (cfg->features & BTRFS_FEATURE_INCOMPAT_ZONED)
btrfs_set_super_cache_generation(&super, 0);
else
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[MKFS_ROOT_TREE]);
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);
ret = btrfs_create_tree_root(fd, cfg, buf);
if (ret < 0)
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 < MKFS_BLOCK_COUNT; 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[MKFS_EXTENT_TREE]);
btrfs_set_header_owner(buf, BTRFS_EXTENT_TREE_OBJECTID);
btrfs_set_header_nritems(buf, nritems);
csum_tree_block_size(buf, btrfs_csum_type_size(cfg->csum_type), 0,
cfg->csum_type);
ret = pwrite(fd, buf->data, cfg->nodesize, cfg->blocks[MKFS_EXTENT_TREE]);
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, 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, system_group_offset);
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, 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,
system_group_offset);
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[MKFS_CHUNK_TREE]);
btrfs_set_header_owner(buf, BTRFS_CHUNK_TREE_OBJECTID);
btrfs_set_header_nritems(buf, nritems);
csum_tree_block_size(buf, btrfs_csum_type_size(cfg->csum_type), 0,
cfg->csum_type);
ret = pwrite(fd, buf->data, cfg->nodesize, cfg->blocks[MKFS_CHUNK_TREE]);
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, system_group_offset);
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,
system_group_offset);
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, system_group_size);
nritems++;
btrfs_set_header_bytenr(buf, cfg->blocks[MKFS_DEV_TREE]);
btrfs_set_header_owner(buf, BTRFS_DEV_TREE_OBJECTID);
btrfs_set_header_nritems(buf, nritems);
csum_tree_block_size(buf, btrfs_csum_type_size(cfg->csum_type), 0,
cfg->csum_type);
ret = pwrite(fd, buf->data, cfg->nodesize, cfg->blocks[MKFS_DEV_TREE]);
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[MKFS_FS_TREE]);
btrfs_set_header_owner(buf, BTRFS_FS_TREE_OBJECTID);
btrfs_set_header_nritems(buf, 0);
csum_tree_block_size(buf, btrfs_csum_type_size(cfg->csum_type), 0,
cfg->csum_type);
ret = pwrite(fd, buf->data, cfg->nodesize, cfg->blocks[MKFS_FS_TREE]);
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[MKFS_CSUM_TREE]);
btrfs_set_header_owner(buf, BTRFS_CSUM_TREE_OBJECTID);
btrfs_set_header_nritems(buf, 0);
csum_tree_block_size(buf, btrfs_csum_type_size(cfg->csum_type), 0,
cfg->csum_type);
ret = pwrite(fd, buf->data, cfg->nodesize, cfg->blocks[MKFS_CSUM_TREE]);
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_csum_type_size(cfg->csum_type), 0,
cfg->csum_type);
ret = sbwrite(fd, buf->data, cfg->blocks[MKFS_SUPER_BLOCK]);
if (ret != BTRFS_SUPER_INFO_SIZE) {
ret = (ret < 0 ? -errno : -EIO);
goto out;
}
ret = fsync(fd);
if (ret)
goto out;
ret = 0;
out:
free(buf);
return ret;
}
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->fs_info->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, now);
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;
}
/*
* 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.
*/
static u64 btrfs_min_global_blk_rsv_size(u32 nodesize)
{
return (u64)nodesize << 10;
}
u64 btrfs_min_dev_size(u32 nodesize, int mixed, u64 meta_profile,
u64 data_profile)
{
u64 reserved = 0;
u64 meta_size;
u64 data_size;
if (mixed)
return 2 * (BTRFS_MKFS_SYSTEM_GROUP_SIZE +
btrfs_min_global_blk_rsv_size(nodesize));
/*
* Minimal size calculation is complex due to several factors:
* 0) Reserved 1M range.
*
* 1) Temporary chunk reuse
* If specified chunk profile is SINGLE, we can reuse
* temporary chunks, no need to allocate new chunks.
*
* 2) Different minimal chunk size for different profiles:
* For initial sys chunk, chunk size is fixed to 4M.
* For single profile, minimal chunk size is 8M for all.
* For other profiles, minimal chunk and stripe size ranges from 8M
* to 64M.
*
* To calculate it a little easier, here we assume we don't reuse any
* temporary chunk, and calculate the size completely by ourselves.
*
* Temporary chunks sizes are always fixed:
* One initial sys chunk, one SINGLE meta, and one SINGLE data.
* The latter two are all 8M, according to @calc_size of
* btrfs_alloc_chunk().
*/
reserved += BTRFS_BLOCK_RESERVED_1M_FOR_SUPER +
BTRFS_MKFS_SYSTEM_GROUP_SIZE + SZ_8M * 2;
/*
* For real chunks, we need to select different sizes:
* For SINGLE, it's still fixed to 8M (@calc_size).
* For other profiles, refer to max(@min_stripe_size, @calc_size).
*
* And use the stripe size to calculate its physical used space.
*/
if (meta_profile & BTRFS_BLOCK_GROUP_PROFILE_MASK)
meta_size = SZ_8M + SZ_32M;
else
meta_size = SZ_8M + SZ_8M;
/* For DUP/metadata, 2 stripes on one disk */
if (meta_profile & BTRFS_BLOCK_GROUP_DUP)
meta_size *= 2;
reserved += meta_size;
if (data_profile & BTRFS_BLOCK_GROUP_PROFILE_MASK)
data_size = SZ_64M;
else
data_size = SZ_8M;
/* For DUP/data, 2 stripes on one disk */
if (data_profile & BTRFS_BLOCK_GROUP_DUP)
data_size *= 2;
reserved += data_size;
return reserved;
}
#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) {
errno = -ret;
error("checking status of %s: %m", file);
return 1;
}
if (ret == 1) {
error("%s is a swap device", file);
return 1;
}
ret = test_status_for_mkfs(file, force_overwrite);
if (ret)
return 1;
/* check if the device is busy */
fd = open(file, O_RDWR|O_EXCL);
if (fd < 0) {
error("unable to open %s: %m", file);
return 1;
}
if (fstat(fd, &st)) {
error("unable to stat %s: %m", file);
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;
}
/*
* check if the file (device) is formatted or mounted
*/
int test_status_for_mkfs(const char *file, bool force_overwrite)
{
int ret;
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) {
errno = -ret;
error("cannot check mount status of %s: %m", file);
return 1;
}
if (ret == 1) {
error("%s is mounted", file);
return 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;
}
}
int test_minimum_size(const char *file, u64 min_dev_size)
{
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) < min_dev_size) {
close(fd);
return 1;
}
close(fd);
return 0;
}
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