[ 3.5.y.z extended stable ] Patch "xen-netfront: frags -> slots in xennet_get_responses" has been added to staging queue

[Luis Henriques]

This is a note to let you know that I have just added a patch titled

    xen-netfront: frags -> slots in xennet_get_responses

to the linux-3.5.y-queue branch of the 3.5.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.5.y-queue

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.5.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

>From 052a14c8e3362bdc20d493704705ba94e23d0286 Mon Sep 17 00:00:00 2001
From: Wei Liu <wei.liu2 at citrix.com>
Date: Mon, 25 Mar 2013 01:08:19 +0000
Subject: [PATCH] xen-netfront: frags -> slots in xennet_get_responses

commit 7158ff6d0c6aa3724fb51c6c11143d31e166eb1f upstream.

This function is in fact counting the ring slots required for responses.
Separate the concepts of ring slots and skb frags make the code clearer, as
now netfront and netback can have different MAX_SKB_FRAGS, slot and frag are
not mapped 1:1 any more.

Signed-off-by: Wei Liu <wei.liu2 at citrix.com>
Reviewed-by: David Vrabel <david.vrabel at citrix.com>
Signed-off-by: David S. Miller <davem at davemloft.net>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 drivers/net/xen-netfront.c | 18 +++++++++---------
 1 file changed, 9 insertions(+), 9 deletions(-)

diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c
index 0ab0da4..9f09606 100644
--- a/drivers/net/xen-netfront.c
+++ b/drivers/net/xen-netfront.c
@@ -656,7 +656,7 @@ static int xennet_get_responses(struct netfront_info *np,
 	struct sk_buff *skb = xennet_get_rx_skb(np, cons);
 	grant_ref_t ref = xennet_get_rx_ref(np, cons);
 	int max = MAX_SKB_FRAGS + (rx->status <= RX_COPY_THRESHOLD);
-	int frags = 1;
+	int slots = 1;
 	int err = 0;
 	unsigned long ret;

@@ -700,27 +700,27 @@ next:
 		if (!(rx->flags & XEN_NETRXF_more_data))
 			break;

-		if (cons + frags == rp) {
+		if (cons + slots == rp) {
 			if (net_ratelimit())
-				dev_warn(dev, "Need more frags\n");
+				dev_warn(dev, "Need more slots\n");
 			err = -ENOENT;
 			break;
 		}

-		rx = RING_GET_RESPONSE(&np->rx, cons + frags);
-		skb = xennet_get_rx_skb(np, cons + frags);
-		ref = xennet_get_rx_ref(np, cons + frags);
-		frags++;
+		rx = RING_GET_RESPONSE(&np->rx, cons + slots);
+		skb = xennet_get_rx_skb(np, cons + slots);
+		ref = xennet_get_rx_ref(np, cons + slots);
+		slots++;
 	}

-	if (unlikely(frags > max)) {
+	if (unlikely(slots > max)) {
 		if (net_ratelimit())
 			dev_warn(dev, "Too many frags\n");
 		err = -E2BIG;
 	}

 	if (unlikely(err))
-		np->rx.rsp_cons = cons + frags;
+		np->rx.rsp_cons = cons + slots;

 	return err;
 }
--
1.8.1.2