Introduce __xdp_build_skb_from_frame and xdp_build_skb_from_frame
utility routine to build the skb from xdp_frame.
Add xdp multi-buff support to cpumap
Signed-off-by: Lorenzo Bianconi <lorenzo@xxxxxxxxxx>
---
include/net/xdp.h | 5 ++++
kernel/bpf/cpumap.c | 45 +------------------------------
net/core/xdp.c | 64 +++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 70 insertions(+), 44 deletions(-)
diff --git a/include/net/xdp.h b/include/net/xdp.h
index 4d47076546ff..8d9224ef75ee 100644
--- a/include/net/xdp.h
+++ b/include/net/xdp.h
@@ -134,6 +134,11 @@ void xdp_warn(const char *msg, const char *func, const int line);
#define XDP_WARN(msg) xdp_warn(msg, __func__, __LINE__)
struct xdp_frame *xdp_convert_zc_to_xdp_frame(struct xdp_buff *xdp);
+struct sk_buff *__xdp_build_skb_from_frame(struct xdp_frame *xdpf,
+ struct sk_buff *skb,
+ struct net_device *dev);
+struct sk_buff *xdp_build_skb_from_frame(struct xdp_frame *xdpf,
+ struct net_device *dev);
static inline
void xdp_convert_frame_to_buff(struct xdp_frame *frame, struct xdp_buff *xdp)
diff --git a/kernel/bpf/cpumap.c b/kernel/bpf/cpumap.c
index c61a23b564aa..fa07b4226836 100644
--- a/kernel/bpf/cpumap.c
+++ b/kernel/bpf/cpumap.c
@@ -155,49 +155,6 @@ static void cpu_map_kthread_stop(struct work_struct *work)
kthread_stop(rcpu->kthread);
}
-static struct sk_buff *cpu_map_build_skb(struct xdp_frame *xdpf,
- struct sk_buff *skb)
-{
- unsigned int hard_start_headroom;
- unsigned int frame_size;
- void *pkt_data_start;
-
- /* Part of headroom was reserved to xdpf */
- hard_start_headroom = sizeof(struct xdp_frame) + xdpf->headroom;
-
- /* Memory size backing xdp_frame data already have reserved
- * room for build_skb to place skb_shared_info in tailroom.
- */
- frame_size = xdpf->frame_sz;
-
- pkt_data_start = xdpf->data - hard_start_headroom;
- skb = build_skb_around(skb, pkt_data_start, frame_size);
- if (unlikely(!skb))
- return NULL;
-
- skb_reserve(skb, hard_start_headroom);
- __skb_put(skb, xdpf->len);
- if (xdpf->metasize)
- skb_metadata_set(skb, xdpf->metasize);
-
- /* Essential SKB info: protocol and skb->dev */
- skb->protocol = eth_type_trans(skb, xdpf->dev_rx);
-
- /* Optional SKB info, currently missing:
- * - HW checksum info (skb->ip_summed)
- * - HW RX hash (skb_set_hash)
- * - RX ring dev queue index (skb_record_rx_queue)
- */
-
- /* Until page_pool get SKB return path, release DMA here */
- xdp_release_frame(xdpf);
-
- /* Allow SKB to reuse area used by xdp_frame */
- xdp_scrub_frame(xdpf);
-
- return skb;
-}
-
static void __cpu_map_ring_cleanup(struct ptr_ring *ring)
{
/* The tear-down procedure should have made sure that queue is
@@ -364,7 +321,7 @@ static int cpu_map_kthread_run(void *data)
struct sk_buff *skb = skbs[i];
int ret;
- skb = cpu_map_build_skb(xdpf, skb);
+ skb = __xdp_build_skb_from_frame(xdpf, skb, xdpf->dev_rx);
if (!skb) {
xdp_return_frame(xdpf);
continue;
diff --git a/net/core/xdp.c b/net/core/xdp.c
index 6d4fd4dddb00..a6bdefed92e6 100644
--- a/net/core/xdp.c
+++ b/net/core/xdp.c
@@ -507,3 +507,67 @@ void xdp_warn(const char *msg, const char *func, const int line)
WARN(1, "XDP_WARN: %s(line:%d): %s\n", func, line, msg);
};
EXPORT_SYMBOL_GPL(xdp_warn);
+
+struct sk_buff *__xdp_build_skb_from_frame(struct xdp_frame *xdpf,
+ struct sk_buff *skb,
+ struct net_device *dev)
+{
+ struct skb_shared_info *sinfo = xdp_get_shared_info_from_frame(xdpf);
+ unsigned int headroom = sizeof(*xdpf) + xdpf->headroom;
+ int i, num_frags = xdpf->mb ? sinfo->nr_frags : 0;
+ void *hard_start = xdpf->data - headroom;
+
+ skb = build_skb_around(skb, hard_start, xdpf->frame_sz);
+ if (unlikely(!skb))
+ return NULL;
+
+ skb_reserve(skb, headroom);
+ __skb_put(skb, xdpf->len);
+ if (xdpf->metasize)
+ skb_metadata_set(skb, xdpf->metasize);
+
+ if (likely(!num_frags))
+ goto out;
+
+ for (i = 0; i < num_frags; i++) {
+ skb_frag_t *frag = &sinfo->frags[i];
+
+ skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags,
+ skb_frag_page(frag), skb_frag_off(frag),
+ skb_frag_size(frag), xdpf->frame_sz);
+ }
+
+out:
+ /* Essential SKB info: protocol and skb->dev */
+ skb->protocol = eth_type_trans(skb, dev);
+
+ /* Optional SKB info, currently missing:
+ * - HW checksum info (skb->ip_summed)
+ * - HW RX hash (skb_set_hash)
+ * - RX ring dev queue index (skb_record_rx_queue)
+ */
+
+ /* Until page_pool get SKB return path, release DMA here */
+ xdp_release_frame(xdpf);
+
+ /* Allow SKB to reuse area used by xdp_frame */
+ xdp_scrub_frame(xdpf);
+
+ return skb;
+}
+EXPORT_SYMBOL_GPL(__xdp_build_skb_from_frame);
+
+struct sk_buff *xdp_build_skb_from_frame(struct xdp_frame *xdpf,
+ struct net_device *dev)
+{
+ struct sk_buff *skb;
+
+ skb = kmem_cache_alloc(skbuff_head_cache, GFP_ATOMIC);
+ if (unlikely(!skb))
+ return NULL;
+
+ memset(skb, 0, offsetof(struct sk_buff, tail));
+
+ return __xdp_build_skb_from_frame(xdpf, skb, dev);
+}
+EXPORT_SYMBOL_GPL(xdp_build_skb_from_frame);
--
2.26.2
