An encoded extent can be up to 128K in length, which exceeds the largest
value expressible by the current send stream format's 16 bit tlv_len
field. Since encoded writes cannot be split into multiple writes by
btrfs send, the send stream format must change to accommodate encoded
writes.
Supporting this changed format requires retooling how we store the
commands we have processed. We currently store pointers to the struct
btrfs_tlv_headers in the command buffer. This is not sufficient to
represent the new BTRFS_SEND_A_DATA format. Instead, parse the attribute
headers and store them in a new struct btrfs_send_attribute which has a
32bit length field. This is transparent to users of the various TLV_GET
macros.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Boris Burkov <boris@bur.io>
Signed-off-by: David Sterba <dsterba@suse.com>
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