diff options
Diffstat (limited to 'drivers/s390/kvm/kvm_virtio.c')
| -rw-r--r-- | drivers/s390/kvm/kvm_virtio.c | 152 |
1 files changed, 123 insertions, 29 deletions
diff --git a/drivers/s390/kvm/kvm_virtio.c b/drivers/s390/kvm/kvm_virtio.c index 2930fc763ac..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 * @@ -10,20 +10,24 @@ * 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> #include <linux/virtio.h> #include <linux/virtio_config.h> +#include <linux/slab.h> #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 @@ -31,6 +35,7 @@ * The pointer to our (page) of device descriptions. */ static void *kvm_devices; +static struct work_struct hotplug_work; struct kvm_device { struct virtio_device vdev; @@ -161,11 +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; } /* @@ -185,6 +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, @@ -193,8 +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; @@ -259,10 +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, @@ -272,6 +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, }; /* @@ -327,63 +345,139 @@ static void scan_devices(void) } /* + * match for a kvm device with a specific desc pointer + */ +static int match_desc(struct device *dev, void *data) +{ + struct virtio_device *vdev = dev_to_virtio(dev); + struct kvm_device *kdev = to_kvmdev(vdev); + + return kdev->desc == data; +} + +/* + * hotplug_device tries to find changes in the device page. + */ +static void hotplug_devices(struct work_struct *dummy) +{ + unsigned int i; + struct kvm_device_desc *d; + struct device *dev; + + for (i = 0; i < PAGE_SIZE; i += desc_size(d)) { + d = kvm_devices + i; + + /* end of list */ + if (d->type == 0) + break; + + /* device already exists */ + dev = device_find_child(kvm_root, d, match_desc); + if (dev) { + /* XXX check for hotplug remove */ + put_device(dev); + continue; + } + + /* new device */ + printk(KERN_INFO "Adding new virtio device %p\n", d); + add_kvm_device(d, i); + } +} + +/* * we emulate the request_irq behaviour on top of s390 extints */ -static void kvm_extint_handler(u16 code) +static void kvm_extint_handler(struct ext_code ext_code, + unsigned int param32, unsigned long param64) { struct virtqueue *vq; - u16 subcode; - int config_changed; + u32 param; - subcode = S390_lowcore.cpu_addr; - 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 *) ((*(long *) __LC_PFAULT_INTPARM) & ~1UL); + vq = (struct virtqueue *)(param64 & ~1UL); - /* We use the LSB of extparam, to decide, if this interrupt is a config - * change or a "standard" interrupt */ - config_changed = (*(int *) __LC_EXT_PARAMS & 1); + /* We use ext_params to decide what this interrupt means */ + param = param32 & VIRTIO_PARAM_MASK; - if (config_changed) { + switch (param) { + case VIRTIO_PARAM_CONFIG_CHANGED: + { struct virtio_driver *drv; drv = container_of(vq->vdev->dev.driver, struct virtio_driver, driver); if (drv->config_changed) drv->config_changed(vq->vdev); - } else + + break; + } + case VIRTIO_PARAM_DEV_ADD: + schedule_work(&hotplug_work); + break; + case VIRTIO_PARAM_VRING_INTERRUPT: + default: vring_interrupt(0, vq); + break; + } } /* + * 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; - } + INIT_WORK(&hotplug_work, hotplug_devices); - kvm_devices = (void *) real_memory_size; - - 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; @@ -405,7 +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); } |