Patch "hv_netvsc: Fix the TX/RX buffer default sizes" has been added to the 4.15-stable tree

Patch "hv_netvsc: Fix the TX/RX buffer default sizes" has been added to the 4.15-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    hv_netvsc: Fix the TX/RX buffer default sizes

to the 4.15-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     hv_netvsc-fix-the-tx-rx-buffer-default-sizes.patch
and it can be found in the queue-4.15 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From foo@baz Thu Mar 22 14:03:39 CET 2018
From: Haiyang Zhang <haiyangz@microsoft.com>
Date: Mon, 11 Dec 2017 08:56:58 -0800
Subject: hv_netvsc: Fix the TX/RX buffer default sizes

From: Haiyang Zhang <haiyangz@microsoft.com>


[ Upstream commit 41f61db2cd24d5ad802386719cccde1479aa82a6 ]

The values were not computed correctly. There are no significant
visible impact, though.

The intended size of RX buffer is 16 MB, and the default slot size is 1728.
So, NETVSC_DEFAULT_RX should be 16*1024*1024 / 1728 = 9709.

The intended size of TX buffer is 1 MB, and the slot size is 6144.
So, NETVSC_DEFAULT_TX should be 1024*1024 / 6144 = 170.

The patch puts the formula directly into the macro, and moves them to
hyperv_net.h, together with related macros.

Fixes: 5023a6db73196 ("netvsc: increase default receive buffer size")
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/net/hyperv/hyperv_net.h |   13 ++++++++++++-
 drivers/net/hyperv/netvsc_drv.c |    4 ----
 2 files changed, 12 insertions(+), 5 deletions(-)

--- a/drivers/net/hyperv/hyperv_net.h
+++ b/drivers/net/hyperv/hyperv_net.h
@@ -638,13 +638,24 @@ struct nvsp_message {
 /* Max buffer sizes allowed by a host */
 #define NETVSC_RECEIVE_BUFFER_SIZE		(1024 * 1024 * 31) /* 31MB */
 #define NETVSC_RECEIVE_BUFFER_SIZE_LEGACY	(1024 * 1024 * 15) /* 15MB */
-#define NETVSC_SEND_BUFFER_SIZE			(1024 * 1024 * 15)   /* 15MB */
+#define NETVSC_RECEIVE_BUFFER_DEFAULT		(1024 * 1024 * 16)
+
+#define NETVSC_SEND_BUFFER_SIZE			(1024 * 1024 * 15)  /* 15MB */
+#define NETVSC_SEND_BUFFER_DEFAULT		(1024 * 1024)
 
 #define NETVSC_INVALID_INDEX			-1
 
 #define NETVSC_SEND_SECTION_SIZE		6144
 #define NETVSC_RECV_SECTION_SIZE		1728
 
+/* Default size of TX buf: 1MB, RX buf: 16MB */
+#define NETVSC_MIN_TX_SECTIONS	10
+#define NETVSC_DEFAULT_TX	(NETVSC_SEND_BUFFER_DEFAULT \
+				 / NETVSC_SEND_SECTION_SIZE)
+#define NETVSC_MIN_RX_SECTIONS	10
+#define NETVSC_DEFAULT_RX	(NETVSC_RECEIVE_BUFFER_DEFAULT \
+				 / NETVSC_RECV_SECTION_SIZE)
+
 #define NETVSC_RECEIVE_BUFFER_ID		0xcafe
 #define NETVSC_SEND_BUFFER_ID			0
 
--- a/drivers/net/hyperv/netvsc_drv.c
+++ b/drivers/net/hyperv/netvsc_drv.c
@@ -46,10 +46,6 @@
 #include "hyperv_net.h"
 
 #define RING_SIZE_MIN		64
-#define NETVSC_MIN_TX_SECTIONS	10
-#define NETVSC_DEFAULT_TX	192	/* ~1M */
-#define NETVSC_MIN_RX_SECTIONS	10	/* ~64K */
-#define NETVSC_DEFAULT_RX	10485   /* Max ~16M */
 
 #define LINKCHANGE_INT (2 * HZ)
 #define VF_TAKEOVER_INT (HZ / 10)


Patches currently in stable-queue which might be from haiyangz@microsoft.com are

queue-4.15/hv_netvsc-fix-the-tx-rx-buffer-default-sizes.patch
queue-4.15/hv_netvsc-fix-the-receive-buffer-size-limit.patch