libceph: move init of bio_iter

(cherry picked from commit 572c588edadaa3da3992bd8a0fed830bbcc861f8)

If a message has a non-null bio pointer, its bio_iter field is
initialized in write_partial_msg_pages() if this has not been done
already.  This is really a one-time setup operation for sending a
message's (bio) data, so move that initialization code into
prepare_write_message_data() which serves that purpose.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/net/ceph/messenger.c b/net/ceph/messenger.c
index f35f0c3..0c097b0 100644 (file)
--- a/net/ceph/messenger.c
+++ b/net/ceph/messenger.c
@@ -603,6 +603,10 @@ static void prepare_write_message_data(struct ceph_connection *con)
                con->out_msg_pos.page_pos = msg->page_alignment;
        else
                con->out_msg_pos.page_pos = 0;
+#ifdef CONFIG_BLOCK
+       if (msg->bio && !msg->bio_iter)
+               init_bio_iter(msg->bio, &msg->bio_iter, &msg->bio_seg);
+#endif
        con->out_msg_pos.data_pos = 0;
        con->out_msg_pos.did_page_crc = false;
        con->out_more = 1;  /* data + footer will follow */
@@ -942,11 +946,6 @@ static int write_partial_msg_pages(struct ceph_connection *con)
             con, msg, con->out_msg_pos.page, msg->nr_pages,
             con->out_msg_pos.page_pos);
 
-#ifdef CONFIG_BLOCK
-       if (msg->bio && !msg->bio_iter)
-               init_bio_iter(msg->bio, &msg->bio_iter, &msg->bio_seg);
-#endif
-
        while (data_len > con->out_msg_pos.data_pos) {
                struct page *page = NULL;
                int max_write = PAGE_SIZE;