btrfs-progs: mkfs: Replace number with enum

For code maintainability and scalability,
replace hardcoded constant with a meaningful enum.

Signed-off-by: Gu Jinxiang <gujx@cn.fujitsu.com>
[ add MKFS_ prefix ]
Signed-off-by: David Sterba <dsterba@suse.com>
This commit is contained in:
Gu Jinxiang 2017-06-28 17:59:24 +08:00 committed by David Sterba
parent fb0d53a937
commit c0d783347f
2 changed files with 39 additions and 24 deletions

View File

@ -93,18 +93,18 @@ int make_btrfs(int fd, struct btrfs_mkfs_config *cfg)
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[MKFS_SUPER_BLOCK] = BTRFS_SUPER_INFO_OFFSET;
for (i = 1; i < MKFS_BLOCK_COUNT; i++) {
cfg->blocks[i] = BTRFS_SUPER_INFO_OFFSET + 1024 * 1024 +
cfg->nodesize * i;
}
btrfs_set_super_bytenr(&super, cfg->blocks[0]);
btrfs_set_super_bytenr(&super, cfg->blocks[MKFS_SUPER_BLOCK]);
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_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);
@ -121,7 +121,7 @@ int make_btrfs(int fd, struct btrfs_mkfs_config *cfg)
/* 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_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);
@ -151,7 +151,7 @@ int make_btrfs(int fd, struct btrfs_mkfs_config *cfg)
nritems = 0;
itemoff = __BTRFS_LEAF_DATA_SIZE(cfg->nodesize) - sizeof(root_item);
btrfs_set_root_bytenr(&root_item, cfg->blocks[2]);
btrfs_set_root_bytenr(&root_item, cfg->blocks[MKFS_EXTENT_TREE]);
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);
@ -162,7 +162,7 @@ int make_btrfs(int fd, struct btrfs_mkfs_config *cfg)
nritems++;
itemoff = itemoff - sizeof(root_item);
btrfs_set_root_bytenr(&root_item, cfg->blocks[4]);
btrfs_set_root_bytenr(&root_item, cfg->blocks[MKFS_DEV_TREE]);
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);
@ -174,7 +174,7 @@ int make_btrfs(int fd, struct btrfs_mkfs_config *cfg)
nritems++;
itemoff = itemoff - sizeof(root_item);
btrfs_set_root_bytenr(&root_item, cfg->blocks[5]);
btrfs_set_root_bytenr(&root_item, cfg->blocks[MKFS_FS_TREE]);
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);
@ -186,7 +186,7 @@ int make_btrfs(int fd, struct btrfs_mkfs_config *cfg)
nritems++;
itemoff = itemoff - sizeof(root_item);
btrfs_set_root_bytenr(&root_item, cfg->blocks[6]);
btrfs_set_root_bytenr(&root_item, cfg->blocks[MKFS_CSUM_TREE]);
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);
@ -199,7 +199,7 @@ int make_btrfs(int fd, struct btrfs_mkfs_config *cfg)
csum_tree_block_size(buf, BTRFS_CRC32_SIZE, 0);
ret = pwrite(fd, buf->data, cfg->nodesize, cfg->blocks[1]);
ret = pwrite(fd, buf->data, cfg->nodesize, cfg->blocks[MKFS_ROOT_TREE]);
if (ret != cfg->nodesize) {
ret = (ret < 0 ? -errno : -EIO);
goto out;
@ -210,7 +210,7 @@ int make_btrfs(int fd, struct btrfs_mkfs_config *cfg)
cfg->nodesize - sizeof(struct btrfs_header));
nritems = 0;
itemoff = __BTRFS_LEAF_DATA_SIZE(cfg->nodesize);
for (i = 1; i < 7; i++) {
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);
@ -267,11 +267,11 @@ int make_btrfs(int fd, struct btrfs_mkfs_config *cfg)
btrfs_set_item_size(buf, btrfs_item_nr(nritems), 0);
nritems++;
}
btrfs_set_header_bytenr(buf, cfg->blocks[2]);
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_CRC32_SIZE, 0);
ret = pwrite(fd, buf->data, cfg->nodesize, cfg->blocks[2]);
ret = pwrite(fd, buf->data, cfg->nodesize, cfg->blocks[MKFS_EXTENT_TREE]);
if (ret != cfg->nodesize) {
ret = (ret < 0 ? -errno : -EIO);
goto out;
@ -354,11 +354,11 @@ int make_btrfs(int fd, struct btrfs_mkfs_config *cfg)
ptr += item_size;
btrfs_set_super_sys_array_size(&super, array_size);
btrfs_set_header_bytenr(buf, cfg->blocks[3]);
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_CRC32_SIZE, 0);
ret = pwrite(fd, buf->data, cfg->nodesize, cfg->blocks[3]);
ret = pwrite(fd, buf->data, cfg->nodesize, cfg->blocks[MKFS_CHUNK_TREE]);
if (ret != cfg->nodesize) {
ret = (ret < 0 ? -errno : -EIO);
goto out;
@ -393,11 +393,11 @@ int make_btrfs(int fd, struct btrfs_mkfs_config *cfg)
BTRFS_MKFS_SYSTEM_GROUP_SIZE);
nritems++;
btrfs_set_header_bytenr(buf, cfg->blocks[4]);
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_CRC32_SIZE, 0);
ret = pwrite(fd, buf->data, cfg->nodesize, cfg->blocks[4]);
ret = pwrite(fd, buf->data, cfg->nodesize, cfg->blocks[MKFS_DEV_TREE]);
if (ret != cfg->nodesize) {
ret = (ret < 0 ? -errno : -EIO);
goto out;
@ -406,11 +406,11 @@ int make_btrfs(int fd, struct btrfs_mkfs_config *cfg)
/* 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_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_CRC32_SIZE, 0);
ret = pwrite(fd, buf->data, cfg->nodesize, cfg->blocks[5]);
ret = pwrite(fd, buf->data, cfg->nodesize, cfg->blocks[MKFS_FS_TREE]);
if (ret != cfg->nodesize) {
ret = (ret < 0 ? -errno : -EIO);
goto out;
@ -418,11 +418,11 @@ int make_btrfs(int fd, struct btrfs_mkfs_config *cfg)
/* 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_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_CRC32_SIZE, 0);
ret = pwrite(fd, buf->data, cfg->nodesize, cfg->blocks[6]);
ret = pwrite(fd, buf->data, cfg->nodesize, cfg->blocks[MKFS_CSUM_TREE]);
if (ret != cfg->nodesize) {
ret = (ret < 0 ? -errno : -EIO);
goto out;
@ -433,7 +433,8 @@ int make_btrfs(int fd, struct btrfs_mkfs_config *cfg)
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]);
ret = pwrite(fd, buf->data, BTRFS_SUPER_INFO_SIZE,
cfg->blocks[MKFS_SUPER_BLOCK]);
if (ret != BTRFS_SUPER_INFO_SIZE) {
ret = (ret < 0 ? -errno : -EIO);
goto out;

View File

@ -28,6 +28,20 @@
#define BTRFS_MKFS_SYSTEM_GROUP_SIZE SZ_4M
#define BTRFS_MKFS_SMALL_VOLUME_SIZE SZ_1G
/*
* Tree root blocks created during mkfs
*/
enum btrfs_mkfs_block {
MKFS_SUPER_BLOCK = 0,
MKFS_ROOT_TREE,
MKFS_EXTENT_TREE,
MKFS_CHUNK_TREE,
MKFS_DEV_TREE,
MKFS_FS_TREE,
MKFS_CSUM_TREE,
MKFS_BLOCK_COUNT
};
struct btrfs_mkfs_config {
/* Label of the new filesystem */
const char *label;
@ -43,7 +57,7 @@ struct btrfs_mkfs_config {
/* Output fields, set during creation */
/* Logical addresses of superblock [0] and other tree roots */
u64 blocks[8];
u64 blocks[MKFS_BLOCK_COUNT + 1];
char fs_uuid[BTRFS_UUID_UNPARSED_SIZE];
char chunk_uuid[BTRFS_UUID_UNPARSED_SIZE];