Using copy_extent_buffer is suitable for copying betwenn buffers from an
arbitrary offset and deals with page boundaries. This is not necessary
when doing a full extent_buffer-to-extent_buffer copy. We can utilize
the copy_page helper as well.
Signed-off-by: David Sterba <dsterba@xxxxxxxx>
---
fs/btrfs/ctree.c | 4 ++--
fs/btrfs/extent_io.c | 14 ++++++++++++++
fs/btrfs/extent_io.h | 2 ++
3 files changed, 18 insertions(+), 2 deletions(-)
diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index be362b776138..25286a5912fc 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -260,7 +260,7 @@ int btrfs_copy_root(struct btrfs_trans_handle *trans,
if (IS_ERR(cow))
return PTR_ERR(cow);
- copy_extent_buffer(cow, buf, 0, 0, cow->len);
+ copy_extent_buffer_full(cow, buf);
btrfs_set_header_bytenr(cow, cow->start);
btrfs_set_header_generation(cow, trans->transid);
btrfs_set_header_backref_rev(cow, BTRFS_MIXED_BACKREF_REV);
@@ -1129,7 +1129,7 @@ static noinline int __btrfs_cow_block(struct btrfs_trans_handle *trans,
/* cow is set to blocking by btrfs_init_new_buffer */
- copy_extent_buffer(cow, buf, 0, 0, cow->len);
+ copy_extent_buffer_full(cow, buf);
btrfs_set_header_bytenr(cow, cow->start);
btrfs_set_header_generation(cow, trans->transid);
btrfs_set_header_backref_rev(cow, BTRFS_MIXED_BACKREF_REV);
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index a7beacbe0087..333491e26742 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -5546,6 +5546,20 @@ void memzero_extent_buffer(struct extent_buffer *eb, unsigned long start,
}
}
+void copy_extent_buffer_full(struct extent_buffer *dst,
+ struct extent_buffer *src)
+{
+ int i;
+ unsigned num_pages;
+
+ ASSERT(dst->len == src->len);
+
+ num_pages = num_extent_pages(dst->start, dst->len);
+ for (i = 0; i < num_pages; i++)
+ copy_page(page_address(dst->pages[i]),
+ page_address(src->pages[i]));
+}
+
void copy_extent_buffer(struct extent_buffer *dst, struct extent_buffer *src,
unsigned long dst_offset, unsigned long src_offset,
unsigned long len)
diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h
index 12fe17523df2..ae64c1917d0a 100644
--- a/fs/btrfs/extent_io.h
+++ b/fs/btrfs/extent_io.h
@@ -410,6 +410,8 @@ 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_full(struct extent_buffer *dst,
+ struct extent_buffer *src);
void copy_extent_buffer(struct extent_buffer *dst, struct extent_buffer *src,
unsigned long dst_offset, unsigned long src_offset,
unsigned long len);
--
2.10.1
--
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