gve: Make gve_rx_slot_page_info.page_offset an absolute offset

Using `page_offset` like a boolean means a page may only be split into
two sections. With page sizes larger than 4k, this can be very wasteful.
Future commits in this patchset use `struct gve_rx_slot_page_info` in a
way which supports a fixed buffer size and a variable page size.

Signed-off-by: Bailey Forrest <bcf@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Catherine Sullivan <csully@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/google/gve/gve.h b/drivers/net/ethernet/google/gve/gve.h
index daf07c0..5467c74 100644 (file)
--- a/drivers/net/ethernet/google/gve/gve.h
+++ b/drivers/net/ethernet/google/gve/gve.h
@@ -1,7 +1,7 @@
 /* SPDX-License-Identifier: (GPL-2.0 OR MIT)
  * Google virtual Ethernet (gve) driver
  *
- * Copyright (C) 2015-2019 Google, Inc.
+ * Copyright (C) 2015-2021 Google, Inc.
  */
 
 #ifndef _GVE_H_
@@ -51,7 +51,7 @@ struct gve_rx_desc_queue {
 struct gve_rx_slot_page_info {
        struct page *page;
        void *page_address;
-       u8 page_offset; /* flipped to second half? */
+       u32 page_offset; /* offset to write to in page */
        u8 can_flip;
 };
 

diff --git a/drivers/net/ethernet/google/gve/gve_rx.c b/drivers/net/ethernet/google/gve/gve_rx.c
index c51578c..e145096 100644 (file)
--- a/drivers/net/ethernet/google/gve/gve_rx.c
+++ b/drivers/net/ethernet/google/gve/gve_rx.c
@@ -272,7 +272,7 @@ static struct sk_buff *gve_rx_add_frags(struct napi_struct *napi,
                return NULL;
 
        skb_add_rx_frag(skb, 0, page_info->page,
-                       (page_info->page_offset ? PAGE_SIZE / 2 : 0) +
+                       page_info->page_offset +
                        GVE_RX_PAD, len, PAGE_SIZE / 2);
 
        return skb;
@@ -283,7 +283,7 @@ static void gve_rx_flip_buff(struct gve_rx_slot_page_info *page_info, __be64 *sl
        const __be64 offset = cpu_to_be64(PAGE_SIZE / 2);
 
        /* "flip" to other packet buffer on this page */
-       page_info->page_offset ^= 0x1;
+       page_info->page_offset ^= PAGE_SIZE / 2;
        *(slot_addr) ^= offset;
 }
 

diff --git a/drivers/net/ethernet/google/gve/gve_utils.c b/drivers/net/ethernet/google/gve/gve_utils.c
index eb3d67c..a0607a8 100644 (file)
--- a/drivers/net/ethernet/google/gve/gve_utils.c
+++ b/drivers/net/ethernet/google/gve/gve_utils.c
@@ -50,7 +50,7 @@ struct sk_buff *gve_rx_copy(struct net_device *dev, struct napi_struct *napi,
 {
        struct sk_buff *skb = napi_alloc_skb(napi, len);
        void *va = page_info->page_address + pad +
-                  (page_info->page_offset ? PAGE_SIZE / 2 : 0);
+                  page_info->page_offset;
 
        if (unlikely(!skb))
                return NULL;