* [PATCH] btrfs-progs: Make the process of create root tree to a function
@ 2017-08-25 7:23 Gu Jinxiang
2017-09-04 16:47 ` David Sterba
0 siblings, 1 reply; 2+ messages in thread
From: Gu Jinxiang @ 2017-08-25 7:23 UTC (permalink / raw)
To: linux-btrfs
make_btrfs is too long to understand, make creatation of root tree
in a function.
Signed-off-by: Gu Jinxiang <gujx@cn.fujitsu.com>
---
mkfs/common.c | 136 +++++++++++++++++++++++++++-------------------------------
1 file changed, 64 insertions(+), 72 deletions(-)
diff --git a/mkfs/common.c b/mkfs/common.c
index 7d482c2..78297fa 100644
--- a/mkfs/common.c
+++ b/mkfs/common.c
@@ -34,6 +34,68 @@ static u64 reference_root_table[] = {
[6] = BTRFS_CSUM_TREE_OBJECTID,
};
+static int btrfs_create_root_tree(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 = 0;
+ int ret = 0;
+ int blk = 0;
+
+ 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));
+ write_extent_buffer(buf, &root_item,
+ btrfs_item_ptr_offset(buf, nritems),
+ sizeof(root_item));
+ nritems++;
+ itemoff = itemoff - sizeof(root_item);
+ }
+
+ /* generate checksum */
+ csum_tree_block_size(buf, BTRFS_CRC32_SIZE, 0);
+
+ /* 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
*
@@ -44,10 +106,8 @@ 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;
@@ -133,77 +193,9 @@ int make_btrfs(int fd, struct btrfs_mkfs_config *cfg)
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[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);
- 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[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);
- 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[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);
- 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[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);
- 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[MKFS_ROOT_TREE]);
- if (ret != cfg->nodesize) {
- ret = (ret < 0 ? -errno : -EIO);
+ ret = btrfs_create_root_tree(fd, cfg, buf);
+ if (ret < 0)
goto out;
- }
/* create the items for the extent tree */
memset(buf->data + sizeof(struct btrfs_header), 0,
--
1.9.1
^ permalink raw reply related [flat|nested] 2+ messages in thread* Re: [PATCH] btrfs-progs: Make the process of create root tree to a function
2017-08-25 7:23 [PATCH] btrfs-progs: Make the process of create root tree to a function Gu Jinxiang
@ 2017-09-04 16:47 ` David Sterba
0 siblings, 0 replies; 2+ messages in thread
From: David Sterba @ 2017-09-04 16:47 UTC (permalink / raw)
To: Gu Jinxiang; +Cc: linux-btrfs
On Fri, Aug 25, 2017 at 03:23:36PM +0800, Gu Jinxiang wrote:
> make_btrfs is too long to understand, make creatation of root tree
> in a function.
Good cleanup, but the changelog could be improved. There are some
changes not obvious from the changes, like that you now iterate some of
the roots and use the reference_root_table for translation. This makes
it a bit harder to review the patch as the code is not just moved to a
function but also improved on the way. Sometimes it's better to do it in
two steps, but not absolutely necessary in this case.
Nevertheless, patch applied, with the updated changelog.
^ permalink raw reply [flat|nested] 2+ messages in thread
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