From 2f7c68cb55ecb7331f2381deb497c27155f32faf Mon Sep 17 00:00:00 2001
From: hc <hc@nodka.com>
Date: Wed, 03 Jan 2024 09:43:39 +0000
Subject: [PATCH] update kernel to 5.10.198

---
 kernel/drivers/net/xen-netback/netback.c |   46 +++++++++++++++++++++++++++++++++++-----------
 1 files changed, 35 insertions(+), 11 deletions(-)

diff --git a/kernel/drivers/net/xen-netback/netback.c b/kernel/drivers/net/xen-netback/netback.c
index f9373a8..1c366dd 100644
--- a/kernel/drivers/net/xen-netback/netback.c
+++ b/kernel/drivers/net/xen-netback/netback.c
@@ -334,6 +334,7 @@
 struct xenvif_tx_cb {
 	u16 copy_pending_idx[XEN_NETBK_LEGACY_SLOTS_MAX + 1];
 	u8 copy_count;
+	u32 split_mask;
 };
 
 #define XENVIF_TX_CB(skb) ((struct xenvif_tx_cb *)(skb)->cb)
@@ -361,6 +362,8 @@
 	struct sk_buff *skb =
 		alloc_skb(size + NET_SKB_PAD + NET_IP_ALIGN,
 			  GFP_ATOMIC | __GFP_NOWARN);
+
+	BUILD_BUG_ON(sizeof(*XENVIF_TX_CB(skb)) > sizeof(skb->cb));
 	if (unlikely(skb == NULL))
 		return NULL;
 
@@ -393,14 +396,16 @@
 	struct gnttab_map_grant_ref *gop = queue->tx_map_ops + *map_ops;
 	struct xen_netif_tx_request *txp = first;
 
-	nr_slots = shinfo->nr_frags + 1;
+	nr_slots = shinfo->nr_frags + frag_overflow + 1;
 
 	copy_count(skb) = 0;
+	XENVIF_TX_CB(skb)->split_mask = 0;
 
 	/* Create copy ops for exactly data_len bytes into the skb head. */
 	__skb_put(skb, data_len);
 	while (data_len > 0) {
 		int amount = data_len > txp->size ? txp->size : data_len;
+		bool split = false;
 
 		cop->source.u.ref = txp->gref;
 		cop->source.domid = queue->vif->domid;
@@ -413,6 +418,13 @@
 		cop->dest.u.gmfn = virt_to_gfn(skb->data + skb_headlen(skb)
 				               - data_len);
 
+		/* Don't cross local page boundary! */
+		if (cop->dest.offset + amount > XEN_PAGE_SIZE) {
+			amount = XEN_PAGE_SIZE - cop->dest.offset;
+			XENVIF_TX_CB(skb)->split_mask |= 1U << copy_count(skb);
+			split = true;
+		}
+
 		cop->len = amount;
 		cop->flags = GNTCOPY_source_gref;
 
@@ -420,7 +432,8 @@
 		pending_idx = queue->pending_ring[index];
 		callback_param(queue, pending_idx).ctx = NULL;
 		copy_pending_idx(skb, copy_count(skb)) = pending_idx;
-		copy_count(skb)++;
+		if (!split)
+			copy_count(skb)++;
 
 		cop++;
 		data_len -= amount;
@@ -441,15 +454,16 @@
 			nr_slots--;
 		} else {
 			/* The copy op partially covered the tx_request.
-			 * The remainder will be mapped.
+			 * The remainder will be mapped or copied in the next
+			 * iteration.
 			 */
 			txp->offset += amount;
 			txp->size -= amount;
 		}
 	}
 
-	for (shinfo->nr_frags = 0; shinfo->nr_frags < nr_slots;
-	     shinfo->nr_frags++, gop++) {
+	for (shinfo->nr_frags = 0; nr_slots > 0 && shinfo->nr_frags < MAX_SKB_FRAGS;
+	     shinfo->nr_frags++, gop++, nr_slots--) {
 		index = pending_index(queue->pending_cons++);
 		pending_idx = queue->pending_ring[index];
 		xenvif_tx_create_map_op(queue, pending_idx, txp,
@@ -462,12 +476,12 @@
 			txp++;
 	}
 
-	if (frag_overflow) {
+	if (nr_slots > 0) {
 
 		shinfo = skb_shinfo(nskb);
 		frags = shinfo->frags;
 
-		for (shinfo->nr_frags = 0; shinfo->nr_frags < frag_overflow;
+		for (shinfo->nr_frags = 0; shinfo->nr_frags < nr_slots;
 		     shinfo->nr_frags++, txp++, gop++) {
 			index = pending_index(queue->pending_cons++);
 			pending_idx = queue->pending_ring[index];
@@ -478,6 +492,11 @@
 		}
 
 		skb_shinfo(skb)->frag_list = nskb;
+	} else if (nskb) {
+		/* A frag_list skb was allocated but it is no longer needed
+		 * because enough slots were converted to copy ops above.
+		 */
+		kfree_skb(nskb);
 	}
 
 	(*copy_ops) = cop - queue->tx_copy_ops;
@@ -539,6 +558,13 @@
 		pending_idx = copy_pending_idx(skb, i);
 
 		newerr = (*gopp_copy)->status;
+
+		/* Split copies need to be handled together. */
+		if (XENVIF_TX_CB(skb)->split_mask & (1U << i)) {
+			(*gopp_copy)++;
+			if (!newerr)
+				newerr = (*gopp_copy)->status;
+		}
 		if (likely(!newerr)) {
 			/* The first frag might still have this slot mapped */
 			if (i < copy_count(skb) - 1 || !sharedslot)
@@ -975,10 +1001,8 @@
 
 		/* No crossing a page as the payload mustn't fragment. */
 		if (unlikely((txreq.offset + txreq.size) > XEN_PAGE_SIZE)) {
-			netdev_err(queue->vif->dev,
-				   "txreq.offset: %u, size: %u, end: %lu\n",
-				   txreq.offset, txreq.size,
-				   (unsigned long)(txreq.offset&~XEN_PAGE_MASK) + txreq.size);
+			netdev_err(queue->vif->dev, "Cross page boundary, txreq.offset: %u, size: %u\n",
+				   txreq.offset, txreq.size);
 			xenvif_fatal_tx_err(queue->vif);
 			break;
 		}

--
Gitblit v1.6.2