- gop->source.u.ref = txp->gref;
- gop->source.domid = vif->domid;
- gop->source.offset = txp->offset;
-
- gop->dest.u.gmfn = virt_to_mfn(page_address(page));
- gop->dest.domid = DOMID_SELF;
- gop->dest.offset = txp->offset;
-
- gop->len = txp->size;
- gop->flags = GNTCOPY_source_gref;
+ dst_offset = 0;
+ first = NULL;
+ while (dst_offset < PAGE_SIZE && slot < nr_slots) {
+ gop->flags = GNTCOPY_source_gref;
+
+ gop->source.u.ref = txp->gref;
+ gop->source.domid = vif->domid;
+ gop->source.offset = txp->offset;
+
+ gop->dest.domid = DOMID_SELF;
+
+ gop->dest.offset = dst_offset;
+ gop->dest.u.gmfn = virt_to_mfn(page_address(page));
+
+ if (dst_offset + txp->size > PAGE_SIZE) {
+ /* This page can only merge a portion
+ * of tx request. Do not increment any
+ * pointer / counter here. The txp
+ * will be dealt with in future
+ * rounds, eventually hitting the
+ * `else` branch.
+ */
+ gop->len = PAGE_SIZE - dst_offset;
+ txp->offset += gop->len;
+ txp->size -= gop->len;
+ dst_offset += gop->len; /* quit loop */
+ } else {
+ /* This tx request can be merged in the page */
+ gop->len = txp->size;
+ dst_offset += gop->len;
+
+ index = pending_index(netbk->pending_cons++);
+
+ pending_idx = netbk->pending_ring[index];
+
+ memcpy(&pending_tx_info[pending_idx].req, txp,
+ sizeof(*txp));
+ xenvif_get(vif);
+
+ pending_tx_info[pending_idx].vif = vif;
+
+ /* Poison these fields, corresponding
+ * fields for head tx req will be set
+ * to correct values after the loop.
+ */
+ netbk->mmap_pages[pending_idx] = (void *)(~0UL);
+ pending_tx_info[pending_idx].head =
+ INVALID_PENDING_RING_IDX;
+
+ if (!first) {
+ first = &pending_tx_info[pending_idx];
+ start_idx = index;
+ head_idx = pending_idx;
+ }
+
+ txp++;
+ slot++;
+ }