btrfs: introduce helpers for updating eb uuids

The fsid and chunk tree uuid are always located in the first page,
we don't need the to use write_extent_buffer.

Signed-off-by: David Sterba <dsterba@suse.com>
This commit is contained in:
David Sterba 2016-11-09 17:43:38 +01:00
parent 2230adffe4
commit f157bf765b
2 changed files with 24 additions and 0 deletions

View File

@ -5465,6 +5465,27 @@ int memcmp_extent_buffer(struct extent_buffer *eb, const void *ptrv,
return ret;
}
void write_extent_buffer_chunk_tree_uuid(struct extent_buffer *eb,
const void *srcv)
{
char *kaddr;
WARN_ON(!PageUptodate(eb->pages[0]));
kaddr = page_address(eb->pages[0]);
memcpy(kaddr + offsetof(struct btrfs_header, chunk_tree_uuid), srcv,
BTRFS_FSID_SIZE);
}
void write_extent_buffer_fsid(struct extent_buffer *eb, const void *srcv)
{
char *kaddr;
WARN_ON(!PageUptodate(eb->pages[0]));
kaddr = page_address(eb->pages[0]);
memcpy(kaddr + offsetof(struct btrfs_header, fsid), srcv,
BTRFS_FSID_SIZE);
}
void write_extent_buffer(struct extent_buffer *eb, const void *srcv,
unsigned long start, unsigned long len)
{

View File

@ -405,6 +405,9 @@ void read_extent_buffer(struct extent_buffer *eb, void *dst,
int read_extent_buffer_to_user(struct extent_buffer *eb, void __user *dst,
unsigned long start,
unsigned long len);
void write_extent_buffer_fsid(struct extent_buffer *eb, const void *src);
void write_extent_buffer_chunk_tree_uuid(struct extent_buffer *eb,
const void *src);
void write_extent_buffer(struct extent_buffer *eb, const void *src,
unsigned long start, unsigned long len);
void copy_extent_buffer(struct extent_buffer *dst, struct extent_buffer *src,