gve: Add page size register to the register_page_list command.

This register is required on platforms with page sizes greater than 4k.
This is because the tx side of the driver vmaps the entire queue page
list of pages into a single flat address space, then uses the entire
space. Without communicating the guest page size to the backend, the
backend will only access the first 4k of each page in the queue page list.

Signed-off-by: Jordan Kimbrough <jrkim@google.com>
Signed-off-by: John Fraker <jfraker@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://lore.kernel.org/r/20231128002648.320892-5-jfraker@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/google/gve/gve_adminq.c

@@ -917,6 +917,7 @@ int gve_adminq_register_page_list(struct gve_priv *priv,
 		.page_list_id = cpu_to_be32(qpl->id),
 		.num_pages = cpu_to_be32(num_entries),
 		.page_address_list_addr = cpu_to_be64(page_list_bus),
+		.page_size = cpu_to_be64(PAGE_SIZE),
 	};
 
 	err = gve_adminq_execute_cmd(priv, &cmd);

drivers/net/ethernet/google/gve/gve_adminq.h

@@ -219,9 +219,10 @@ struct gve_adminq_register_page_list {
 	__be32 page_list_id;
 	__be32 num_pages;
 	__be64 page_address_list_addr;
+	__be64 page_size;
 };
 
-static_assert(sizeof(struct gve_adminq_register_page_list) == 16);
+static_assert(sizeof(struct gve_adminq_register_page_list) == 24);
 
 struct gve_adminq_unregister_page_list {
 	__be32 page_list_id;