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path: root/drivers/s390/kvm/kvm_virtio.c
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Diffstat (limited to 'drivers/s390/kvm/kvm_virtio.c')
-rw-r--r--drivers/s390/kvm/kvm_virtio.c92
1 files changed, 65 insertions, 27 deletions
diff --git a/drivers/s390/kvm/kvm_virtio.c b/drivers/s390/kvm/kvm_virtio.c
index 375aeeaf9ea..a1349653c6d 100644
--- a/drivers/s390/kvm/kvm_virtio.c
+++ b/drivers/s390/kvm/kvm_virtio.c
@@ -1,5 +1,5 @@
/*
- * kvm_virtio.c - virtio for kvm on s390
+ * virtio for kvm on s390
*
* Copyright IBM Corp. 2008
*
@@ -10,6 +10,7 @@
* Author(s): Christian Borntraeger <borntraeger@de.ibm.com>
*/
+#include <linux/kernel_stat.h>
#include <linux/init.h>
#include <linux/bootmem.h>
#include <linux/err.h>
@@ -19,12 +20,14 @@
#include <linux/virtio_console.h>
#include <linux/interrupt.h>
#include <linux/virtio_ring.h>
+#include <linux/export.h>
#include <linux/pfn.h>
#include <asm/io.h>
#include <asm/kvm_para.h>
#include <asm/kvm_virtio.h>
+#include <asm/sclp.h>
#include <asm/setup.h>
-#include <asm/s390_ext.h>
+#include <asm/irq.h>
#define VIRTIO_SUBCODE_64 0x0D00
@@ -32,7 +35,7 @@
* The pointer to our (page) of device descriptions.
*/
static void *kvm_devices;
-struct work_struct hotplug_work;
+static struct work_struct hotplug_work;
struct kvm_device {
struct virtio_device vdev;
@@ -163,11 +166,15 @@ static void kvm_reset(struct virtio_device *vdev)
* make a hypercall. We hand the address of the virtqueue so the Host
* knows which virtqueue we're talking about.
*/
-static void kvm_notify(struct virtqueue *vq)
+static bool kvm_notify(struct virtqueue *vq)
{
+ long rc;
struct kvm_vqconfig *config = vq->priv;
- kvm_hypercall1(KVM_S390_VIRTIO_NOTIFY, config->address);
+ rc = kvm_hypercall1(KVM_S390_VIRTIO_NOTIFY, config->address);
+ if (rc < 0)
+ return false;
+ return true;
}
/*
@@ -187,6 +194,9 @@ static struct virtqueue *kvm_find_vq(struct virtio_device *vdev,
if (index >= kdev->desc->num_vq)
return ERR_PTR(-ENOENT);
+ if (!name)
+ return NULL;
+
config = kvm_vq_config(kdev->desc)+index;
err = vmem_add_mapping(config->address,
@@ -195,8 +205,8 @@ static struct virtqueue *kvm_find_vq(struct virtio_device *vdev,
if (err)
goto out;
- vq = vring_new_virtqueue(config->num, KVM_S390_VIRTIO_RING_ALIGN,
- vdev, (void *) config->address,
+ vq = vring_new_virtqueue(index, config->num, KVM_S390_VIRTIO_RING_ALIGN,
+ vdev, true, (void *) config->address,
kvm_notify, callback, name);
if (!vq) {
err = -ENOMEM;
@@ -261,10 +271,15 @@ error:
return PTR_ERR(vqs[i]);
}
+static const char *kvm_bus_name(struct virtio_device *vdev)
+{
+ return "";
+}
+
/*
* The config ops structure as defined by virtio config
*/
-static struct virtio_config_ops kvm_vq_configspace_ops = {
+static const struct virtio_config_ops kvm_vq_configspace_ops = {
.get_features = kvm_get_features,
.finalize_features = kvm_finalize_features,
.get = kvm_get,
@@ -274,6 +289,7 @@ static struct virtio_config_ops kvm_vq_configspace_ops = {
.reset = kvm_reset,
.find_vqs = kvm_find_vqs,
.del_vqs = kvm_del_vqs,
+ .bus_name = kvm_bus_name,
};
/*
@@ -333,10 +349,10 @@ static void scan_devices(void)
*/
static int match_desc(struct device *dev, void *data)
{
- if ((ulong)to_kvmdev(dev_to_virtio(dev))->desc == (ulong)data)
- return 1;
+ struct virtio_device *vdev = dev_to_virtio(dev);
+ struct kvm_device *kdev = to_kvmdev(vdev);
- return 0;
+ return kdev->desc == data;
}
/*
@@ -372,16 +388,15 @@ static void hotplug_devices(struct work_struct *dummy)
/*
* we emulate the request_irq behaviour on top of s390 extints
*/
-static void kvm_extint_handler(unsigned int ext_int_code,
+static void kvm_extint_handler(struct ext_code ext_code,
unsigned int param32, unsigned long param64)
{
struct virtqueue *vq;
- u16 subcode;
u32 param;
- subcode = ext_int_code >> 16;
- if ((subcode & 0xff00) != VIRTIO_SUBCODE_64)
+ if ((ext_code.subcode & 0xff00) != VIRTIO_SUBCODE_64)
return;
+ inc_irq_stat(IRQEXT_VRT);
/* The LSB might be overloaded, we have to mask it */
vq = (struct virtqueue *)(param64 & ~1UL);
@@ -411,35 +426,58 @@ static void kvm_extint_handler(unsigned int ext_int_code,
}
/*
+ * For s390-virtio, we expect a page above main storage containing
+ * the virtio configuration. Try to actually load from this area
+ * in order to figure out if the host provides this page.
+ */
+static int __init test_devices_support(unsigned long addr)
+{
+ int ret = -EIO;
+
+ asm volatile(
+ "0: lura 0,%1\n"
+ "1: xgr %0,%0\n"
+ "2:\n"
+ EX_TABLE(0b,2b)
+ EX_TABLE(1b,2b)
+ : "+d" (ret)
+ : "a" (addr)
+ : "0", "cc");
+ return ret;
+}
+/*
* Init function for virtio
- * devices are in a single page above top of "normal" mem
+ * devices are in a single page above top of "normal" + standby mem
*/
static int __init kvm_devices_init(void)
{
int rc;
+ unsigned long total_memory_size = sclp_get_rzm() * sclp_get_rnmax();
if (!MACHINE_IS_KVM)
return -ENODEV;
+ if (test_devices_support(total_memory_size) < 0)
+ return -ENODEV;
+
+ rc = vmem_add_mapping(total_memory_size, PAGE_SIZE);
+ if (rc)
+ return rc;
+
+ kvm_devices = (void *) total_memory_size;
+
kvm_root = root_device_register("kvm_s390");
if (IS_ERR(kvm_root)) {
rc = PTR_ERR(kvm_root);
printk(KERN_ERR "Could not register kvm_s390 root device");
+ vmem_remove_mapping(total_memory_size, PAGE_SIZE);
return rc;
}
- rc = vmem_add_mapping(real_memory_size, PAGE_SIZE);
- if (rc) {
- root_device_unregister(kvm_root);
- return rc;
- }
-
- kvm_devices = (void *) real_memory_size;
-
INIT_WORK(&hotplug_work, hotplug_devices);
- ctl_set_bit(0, 9);
- register_external_interrupt(0x2603, kvm_extint_handler);
+ irq_subclass_register(IRQ_SUBCLASS_SERVICE_SIGNAL);
+ register_external_irq(EXT_IRQ_CP_SERVICE, kvm_extint_handler);
scan_devices();
return 0;
@@ -461,7 +499,7 @@ static __init int early_put_chars(u32 vtermno, const char *buf, int count)
static int __init s390_virtio_console_init(void)
{
- if (!MACHINE_IS_KVM)
+ if (sclp_has_vt220() || sclp_has_linemode())
return -ENODEV;
return virtio_cons_early_init(early_put_chars);
}