From db40598863e8cbbd11053ad3c8bae89000f603f9 Mon Sep 17 00:00:00 2001
From: Rusty Russell <rusty@rustcorp.com.au>
Date: Tue, 30 Dec 2008 09:26:02 -0600
Subject: [PATCH] virtio: use KVM_S390_VIRTIO_RING_ALIGN instead of relying on
pagesize
This doesn't really matter, since s390 pagesize is 4k anyway.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/include/asm/kvm_virtio.h | 4 ++++
drivers/s390/kvm/kvm_virtio.c | 9 ++++++---
2 files changed, 10 insertions(+), 3 deletions(-)
diff --git a/arch/s390/include/asm/kvm_virtio.h b/arch/s390/include/asm/kvm_virtio.h
index c13568b9351..0503936f101 100644
--- a/arch/s390/include/asm/kvm_virtio.h
+++ b/arch/s390/include/asm/kvm_virtio.h
@@ -50,6 +50,10 @@ struct kvm_vqconfig {
#define KVM_S390_VIRTIO_RESET 1
#define KVM_S390_VIRTIO_SET_STATUS 2
+/* The alignment to use between consumer and producer parts of vring.
+ * This is pagesize for historical reasons. */
+#define KVM_S390_VIRTIO_RING_ALIGN 4096
+
#ifdef __KERNEL__
/* early virtio console setup */
#ifdef CONFIG_S390_GUEST
diff --git a/drivers/s390/kvm/kvm_virtio.c b/drivers/s390/kvm/kvm_virtio.c
index 3d442444c61..f5a2dbe7557 100644
--- a/drivers/s390/kvm/kvm_virtio.c
+++ b/drivers/s390/kvm/kvm_virtio.c
@@ -188,7 +188,8 @@ static struct virtqueue *kvm_find_vq(struct virtio_device *vdev,
config = kvm_vq_config(kdev->desc)+index;
err = vmem_add_mapping(config->address,
- vring_size(config->num, PAGE_SIZE));
+ vring_size(config->num,
+ KVM_S390_VIRTIO_RING_ALIGN));
if (err)
goto out;
@@ -209,7 +210,8 @@ static struct virtqueue *kvm_find_vq(struct virtio_device *vdev,
return vq;
unmap:
vmem_remove_mapping(config->address,
- vring_size(config->num, PAGE_SIZE));
+ vring_size(config->num,
+ KVM_S390_VIRTIO_RING_ALIGN));
out:
return ERR_PTR(err);
}
@@ -220,7 +222,8 @@ static void kvm_del_vq(struct virtqueue *vq)
vring_del_virtqueue(vq);
vmem_remove_mapping(config->address,
- vring_size(config->num, PAGE_SIZE));
+ vring_size(config->num,
+ KVM_S390_VIRTIO_RING_ALIGN));
}
/*
--
2.41.3