libceph: support sparse reads on msgr2 secure codepath

Add a new init_sgs_pages helper that populates the scatterlist from
an arbitrary point in an array of pages.

Change setup_message_sgs to take an optional pointer to an array of
pages. If that's set, then the scatterlist will be set using that
array instead of the cursor.

When given a sparse read on a secure connection, decrypt the data
in-place rather than into the final destination, by passing it the
in_enc_pages array.

After decrypting, run the sparse_read state machine in a loop, copying
data from the decrypted pages until it's complete.

Signed-off-by: Jeff Layton <[email protected]>
Reviewed-by: Xiubo Li <[email protected]>
Reviewed-and-tested-by: Luís Henriques <[email protected]>
Reviewed-by: Milind Changire <[email protected]>
Signed-off-by: Ilya Dryomov <[email protected]>

0 files changed, 0 insertions, 0 deletions