From: Himadri Pandya <himadrispandya@gmail.com>
Date: Thu, 25 Jul 2019 05:03:14 +0000
Patch-mainline: v5.5-rc1
Subject: Drivers: hv: Specify receive buffer size using Hyper-V page size
Git-commit: b14d749ac5abdf311321172ae11e6ad1be4293e9
References: bsc#1176877

The recv_buffer is used to retrieve data from the VMbus ring buffer.
VMbus ring buffers are sized based on the guest page size which
Hyper-V assumes to be 4KB. But it may be different on some
architectures. So use the Hyper-V page size to allocate the
recv_buffer and set the maximum size to receive.

Signed-off-by: Himadri Pandya <himadri18.07@gmail.com>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Acked-by: Olaf Hering <ohering@suse.de>
---
 drivers/hv/hv_fcopy.c    | 3 ++-
 drivers/hv/hv_kvp.c      | 3 ++-
 drivers/hv/hv_snapshot.c | 3 ++-
 drivers/hv/hv_util.c     | 8 ++++----
 4 files changed, 10 insertions(+), 7 deletions(-)

diff --git a/drivers/hv/hv_fcopy.c b/drivers/hv/hv_fcopy.c
--- a/drivers/hv/hv_fcopy.c
+++ b/drivers/hv/hv_fcopy.c
@@ -13,6 +13,7 @@
 #include <linux/workqueue.h>
 #include <linux/hyperv.h>
 #include <linux/sched.h>
+#include <asm/hyperv-tlfs.h>
 
 #include "hyperv_vmbus.h"
 #include "hv_utils_transport.h"
@@ -234,7 +235,7 @@ void hv_fcopy_onchannelcallback(void *context)
 	if (fcopy_transaction.state > HVUTIL_READY)
 		return;
 
-	vmbus_recvpacket(channel, recv_buffer, PAGE_SIZE * 2, &recvlen,
+	vmbus_recvpacket(channel, recv_buffer, HV_HYP_PAGE_SIZE * 2, &recvlen,
 			 &requestid);
 	if (recvlen <= 0)
 		return;
diff --git a/drivers/hv/hv_kvp.c b/drivers/hv/hv_kvp.c
--- a/drivers/hv/hv_kvp.c
+++ b/drivers/hv/hv_kvp.c
@@ -27,6 +27,7 @@
 #include <linux/connector.h>
 #include <linux/workqueue.h>
 #include <linux/hyperv.h>
+#include <asm/hyperv-tlfs.h>
 
 #include "hyperv_vmbus.h"
 #include "hv_utils_transport.h"
@@ -661,7 +662,7 @@ void hv_kvp_onchannelcallback(void *context)
 	if (kvp_transaction.state > HVUTIL_READY)
 		return;
 
-	vmbus_recvpacket(channel, recv_buffer, PAGE_SIZE * 4, &recvlen,
+	vmbus_recvpacket(channel, recv_buffer, HV_HYP_PAGE_SIZE * 4, &recvlen,
 			 &requestid);
 
 	if (recvlen > 0) {
diff --git a/drivers/hv/hv_snapshot.c b/drivers/hv/hv_snapshot.c
--- a/drivers/hv/hv_snapshot.c
+++ b/drivers/hv/hv_snapshot.c
@@ -12,6 +12,7 @@
 #include <linux/connector.h>
 #include <linux/workqueue.h>
 #include <linux/hyperv.h>
+#include <asm/hyperv-tlfs.h>
 
 #include "hyperv_vmbus.h"
 #include "hv_utils_transport.h"
@@ -297,7 +298,7 @@ void hv_vss_onchannelcallback(void *context)
 	if (vss_transaction.state > HVUTIL_READY)
 		return;
 
-	vmbus_recvpacket(channel, recv_buffer, PAGE_SIZE * 2, &recvlen,
+	vmbus_recvpacket(channel, recv_buffer, HV_HYP_PAGE_SIZE * 2, &recvlen,
 			 &requestid);
 
 	if (recvlen > 0) {
diff --git a/drivers/hv/hv_util.c b/drivers/hv/hv_util.c
--- a/drivers/hv/hv_util.c
+++ b/drivers/hv/hv_util.c
@@ -136,7 +136,7 @@ static void shutdown_onchannelcallback(void *context)
 	struct icmsg_hdr *icmsghdrp;
 
 	vmbus_recvpacket(channel, shut_txf_buf,
-			 PAGE_SIZE, &recvlen, &requestid);
+			 HV_HYP_PAGE_SIZE, &recvlen, &requestid);
 
 	if (recvlen > 0) {
 		icmsghdrp = (struct icmsg_hdr *)&shut_txf_buf[
@@ -284,7 +284,7 @@ static void timesync_onchannelcallback(void *context)
 	u8 *time_txf_buf = util_timesynch.recv_buffer;
 
 	vmbus_recvpacket(channel, time_txf_buf,
-			 PAGE_SIZE, &recvlen, &requestid);
+			 HV_HYP_PAGE_SIZE, &recvlen, &requestid);
 
 	if (recvlen > 0) {
 		icmsghdrp = (struct icmsg_hdr *)&time_txf_buf[
@@ -346,7 +346,7 @@ static void heartbeat_onchannelcallback(void *context)
 	while (1) {
 
 		vmbus_recvpacket(channel, hbeat_txf_buf,
-				 PAGE_SIZE, &recvlen, &requestid);
+				 HV_HYP_PAGE_SIZE, &recvlen, &requestid);
 
 		if (!recvlen)
 			break;
@@ -390,7 +390,7 @@ static int util_probe(struct hv_device *dev,
 		(struct hv_util_service *)dev_id->driver_data;
 	int ret;
 
-	srv->recv_buffer = kmalloc(PAGE_SIZE * 4, GFP_KERNEL);
+	srv->recv_buffer = kmalloc(HV_HYP_PAGE_SIZE * 4, GFP_KERNEL);
 	if (!srv->recv_buffer)
 		return -ENOMEM;
 	srv->channel = dev->channel;