1 files changed, 90 insertions, 0 deletions

diff --git a/drivers/net/ethernet/intel/libeth/xdp.c b/drivers/net/ethernet/intel/libeth/xdp.c
index 6f62603cf568..d0669f1f02f3 100644
--- a/drivers/net/ethernet/intel/libeth/xdp.c
+++ b/drivers/net/ethernet/intel/libeth/xdp.c
@@ -175,6 +175,64 @@ EXPORT_SYMBOL_GPL(libeth_xdp_xmit_return_bulk);
 /* Rx polling path */
 
 /**
+ * libeth_xdp_load_stash - recreate an &xdp_buff from libeth_xdp buffer stash
+ * @dst: target &libeth_xdp_buff to initialize
+ * @src: source stash
+ *
+ * External helper used by libeth_xdp_init_buff(), do not call directly.
+ * Recreate an onstack &libeth_xdp_buff using the stash saved earlier.
+ * The only field untouched (rxq) is initialized later in the
+ * abovementioned function.
+ */
+void libeth_xdp_load_stash(struct libeth_xdp_buff *dst,
+			   const struct libeth_xdp_buff_stash *src)
+{
+	dst->data = src->data;
+	dst->base.data_end = src->data + src->len;
+	dst->base.data_meta = src->data;
+	dst->base.data_hard_start = src->data - src->headroom;
+
+	dst->base.frame_sz = src->frame_sz;
+	dst->base.flags = src->flags;
+}
+EXPORT_SYMBOL_GPL(libeth_xdp_load_stash);
+
+/**
+ * libeth_xdp_save_stash - convert &xdp_buff to a libeth_xdp buffer stash
+ * @dst: target &libeth_xdp_buff_stash to initialize
+ * @src: source XDP buffer
+ *
+ * External helper used by libeth_xdp_save_buff(), do not call directly.
+ * Use the fields from the passed XDP buffer to initialize the stash on the
+ * queue, so that a partially received frame can be finished later during
+ * the next NAPI poll.
+ */
+void libeth_xdp_save_stash(struct libeth_xdp_buff_stash *dst,
+			   const struct libeth_xdp_buff *src)
+{
+	dst->data = src->data;
+	dst->headroom = src->data - src->base.data_hard_start;
+	dst->len = src->base.data_end - src->data;
+
+	dst->frame_sz = src->base.frame_sz;
+	dst->flags = src->base.flags;
+
+	WARN_ON_ONCE(dst->flags != src->base.flags);
+}
+EXPORT_SYMBOL_GPL(libeth_xdp_save_stash);
+
+void __libeth_xdp_return_stash(struct libeth_xdp_buff_stash *stash)
+{
+	LIBETH_XDP_ONSTACK_BUFF(xdp);
+
+	libeth_xdp_load_stash(xdp, stash);
+	libeth_xdp_return_buff_slow(xdp);
+
+	stash->data = NULL;
+}
+EXPORT_SYMBOL_GPL(__libeth_xdp_return_stash);
+
+/**
  * libeth_xdp_return_buff_slow - free &libeth_xdp_buff
  * @xdp: buffer to free/return
  *
@@ -187,6 +245,38 @@ void __cold libeth_xdp_return_buff_slow(struct libeth_xdp_buff *xdp)
 }
 EXPORT_SYMBOL_GPL(libeth_xdp_return_buff_slow);
 
+/**
+ * libeth_xdp_buff_add_frag - add frag to XDP buffer
+ * @xdp: head XDP buffer
+ * @fqe: Rx buffer containing the frag
+ * @len: frag length reported by HW
+ *
+ * External helper used by libeth_xdp_process_buff(), do not call directly.
+ * Frees both head and frag buffers on error.
+ *
+ * Return: true success, false on error (no space for a new frag).
+ */
+bool libeth_xdp_buff_add_frag(struct libeth_xdp_buff *xdp,
+			      const struct libeth_fqe *fqe,
+			      u32 len)
+{
+	netmem_ref netmem = fqe->netmem;
+
+	if (!xdp_buff_add_frag(&xdp->base, netmem,
+			       fqe->offset + netmem_get_pp(netmem)->p.offset,
+			       len, fqe->truesize))
+		goto recycle;
+
+	return true;
+
+recycle:
+	libeth_rx_recycle_slow(netmem);
+	libeth_xdp_return_buff_slow(xdp);
+
+	return false;
+}
+EXPORT_SYMBOL_GPL(libeth_xdp_buff_add_frag);
+
 /* Tx buffer completion */
 
 static void libeth_xdp_put_netmem_bulk(netmem_ref netmem,