new file mode 100644
@@ -0,0 +1,36 @@
+FLIC (floating interrupt controller)
+====================================
+
+FLIC handles floating (non per-cpu) interrupts, i.e. I/O, service and some
+machine check interruptions. All interrupts are stored in a per-vm list of
+pending interrupts. FLIC performs operations on this list.
+
+Only one FLIC instance may be instantiated.
+
+FLIC provides support to
+- add interrupts (KVM_DEV_FLIC_ENQUEUE)
+- inspect currently pending interrupts (KVM_FLIC_GET_ALL_IRQS)
+- purge all pending floating interrupts (KVM_DEV_FLIC_CLEAR_IRQS)
+
+Groups:
+ KVM_DEV_FLIC_ENQUEUE
+ Passes a buffer and length into the kernel which are then injected into
+ the list of pending interrupts.
+ attr->addr contains the pointer to the buffer and attr->attr contains
+ the length of the buffer.
+ The format of the data structure kvm_s390_irq as it is copied from userspace
+ is defined in usr/include/linux/kvm.h.
+
+ KVM_DEV_FLIC_GET_ALL_IRQS
+ Copies all floating interrupts into a buffer provided by userspace.
+ When the buffer is too small it returns -ENOMEM, which is the indication
+ for userspace to try again with a bigger buffer.
+ All interrupts remain pending, i.e. are not deleted from the list of
+ currently pending interrupts.
+ attr->addr contains the userspace address of the buffer into which all
+ interrupt data will be copied.
+ attr->attr contains the size of the buffer in bytes.
+
+ KVM_DEV_FLIC_CLEAR_IRQS
+ Simply deletes all elements from the list of currently pending floating
+ interrupts. No interrupts are injected into the guest.
@@ -243,6 +243,7 @@ struct kvm_arch{
struct sca_block *sca;
debug_info_t *dbf;
struct kvm_s390_float_interrupt float_int;
+ struct kvm_device *flic;
struct gmap *gmap;
int css_support;
};
@@ -16,6 +16,20 @@
#define __KVM_S390
+/* Device control API: s390-specific devices */
+#define KVM_DEV_FLIC_GET_ALL_IRQS 1
+#define KVM_DEV_FLIC_ENQUEUE 2
+#define KVM_DEV_FLIC_CLEAR_IRQS 3
+/*
+ * We can have up to 4*64k pending subchannels + 8 adapter interrupts,
+ * as well as up to ASYNC_PF_PER_VCPU*KVM_MAX_VCPUS pfault done interrupts.
+ * There are also sclp and machine checks. This gives us
+ * sizeof(kvm_s390_irq)*(4*65536+8+64*64+1+1) = 72 * 266250 = 19170000
+ * Lets round up to 8192 pages.
+ */
+
+#define KVM_S390_FLIC_MAX_BUFFER 0x2000000
+
/* for KVM_GET_REGS and KVM_SET_REGS */
struct kvm_regs {
/* general purpose regs for s390 */
@@ -659,53 +659,86 @@ struct kvm_s390_interrupt_info *kvm_s390_get_io_int(struct kvm *kvm,
return inti;
}
-int kvm_s390_inject_vm(struct kvm *kvm,
- struct kvm_s390_interrupt *s390int)
+static void __inject_vm(struct kvm *kvm, struct kvm_s390_interrupt_info *inti)
{
struct kvm_s390_local_interrupt *li;
struct kvm_s390_float_interrupt *fi;
- struct kvm_s390_interrupt_info *inti, *iter;
+ struct kvm_s390_interrupt_info *iter;
int sigcpu;
+ mutex_lock(&kvm->lock);
+ fi = &kvm->arch.float_int;
+ spin_lock(&fi->lock);
+ if (!is_ioint(inti->type)) {
+ list_add_tail(&inti->list, &fi->list);
+ } else {
+ u64 isc_bits = int_word_to_isc_bits(inti->io.io_int_word);
+
+ /* Keep I/O interrupts sorted in isc order. */
+ list_for_each_entry(iter, &fi->list, list) {
+ if (!is_ioint(iter->type))
+ continue;
+ if (int_word_to_isc_bits(iter->io.io_int_word)
+ <= isc_bits)
+ continue;
+ break;
+ }
+ list_add_tail(&inti->list, &iter->list);
+ }
+ atomic_set(&fi->active, 1);
+ sigcpu = find_first_bit(fi->idle_mask, KVM_MAX_VCPUS);
+ if (sigcpu == KVM_MAX_VCPUS) {
+ do {
+ sigcpu = fi->next_rr_cpu++;
+ if (sigcpu == KVM_MAX_VCPUS)
+ sigcpu = fi->next_rr_cpu = 0;
+ } while (fi->local_int[sigcpu] == NULL);
+ }
+ li = fi->local_int[sigcpu];
+ spin_lock_bh(&li->lock);
+ atomic_set_mask(CPUSTAT_EXT_INT, li->cpuflags);
+ if (waitqueue_active(li->wq))
+ wake_up_interruptible(li->wq);
+ spin_unlock_bh(&li->lock);
+ spin_unlock(&fi->lock);
+ mutex_unlock(&kvm->lock);
+}
+
+int kvm_s390_inject_vm(struct kvm *kvm,
+ struct kvm_s390_interrupt *s390int)
+{
+ struct kvm_s390_interrupt_info *inti;
+
inti = kzalloc(sizeof(*inti), GFP_KERNEL);
if (!inti)
return -ENOMEM;
- switch (s390int->type) {
+ inti->type = s390int->type;
+ switch (inti->type) {
case KVM_S390_INT_VIRTIO:
VM_EVENT(kvm, 5, "inject: virtio parm:%x,parm64:%llx",
s390int->parm, s390int->parm64);
- inti->type = s390int->type;
inti->ext.ext_params = s390int->parm;
inti->ext.ext_params2 = s390int->parm64;
break;
case KVM_S390_INT_SERVICE:
VM_EVENT(kvm, 5, "inject: sclp parm:%x", s390int->parm);
- inti->type = s390int->type;
inti->ext.ext_params = s390int->parm;
break;
- case KVM_S390_PROGRAM_INT:
- case KVM_S390_SIGP_STOP:
- case KVM_S390_INT_EXTERNAL_CALL:
- case KVM_S390_INT_EMERGENCY:
- kfree(inti);
- return -EINVAL;
case KVM_S390_MCHK:
VM_EVENT(kvm, 5, "inject: machine check parm64:%llx",
s390int->parm64);
- inti->type = s390int->type;
inti->mchk.cr14 = s390int->parm; /* upper bits are not used */
inti->mchk.mcic = s390int->parm64;
break;
case KVM_S390_INT_IO_MIN...KVM_S390_INT_IO_MAX:
- if (s390int->type & IOINT_AI_MASK)
+ if (inti->type & IOINT_AI_MASK)
VM_EVENT(kvm, 5, "%s", "inject: I/O (AI)");
else
VM_EVENT(kvm, 5, "inject: I/O css %x ss %x schid %04x",
s390int->type & IOINT_CSSID_MASK,
s390int->type & IOINT_SSID_MASK,
s390int->type & IOINT_SCHID_MASK);
- inti->type = s390int->type;
inti->io.subchannel_id = s390int->parm >> 16;
inti->io.subchannel_nr = s390int->parm & 0x0000ffffu;
inti->io.io_int_parm = s390int->parm64 >> 32;
@@ -718,42 +751,7 @@ int kvm_s390_inject_vm(struct kvm *kvm,
trace_kvm_s390_inject_vm(s390int->type, s390int->parm, s390int->parm64,
2);
- mutex_lock(&kvm->lock);
- fi = &kvm->arch.float_int;
- spin_lock(&fi->lock);
- if (!is_ioint(inti->type))
- list_add_tail(&inti->list, &fi->list);
- else {
- u64 isc_bits = int_word_to_isc_bits(inti->io.io_int_word);
-
- /* Keep I/O interrupts sorted in isc order. */
- list_for_each_entry(iter, &fi->list, list) {
- if (!is_ioint(iter->type))
- continue;
- if (int_word_to_isc_bits(iter->io.io_int_word)
- <= isc_bits)
- continue;
- break;
- }
- list_add_tail(&inti->list, &iter->list);
- }
- atomic_set(&fi->active, 1);
- sigcpu = find_first_bit(fi->idle_mask, KVM_MAX_VCPUS);
- if (sigcpu == KVM_MAX_VCPUS) {
- do {
- sigcpu = fi->next_rr_cpu++;
- if (sigcpu == KVM_MAX_VCPUS)
- sigcpu = fi->next_rr_cpu = 0;
- } while (fi->local_int[sigcpu] == NULL);
- }
- li = fi->local_int[sigcpu];
- spin_lock_bh(&li->lock);
- atomic_set_mask(CPUSTAT_EXT_INT, li->cpuflags);
- if (waitqueue_active(li->wq))
- wake_up_interruptible(li->wq);
- spin_unlock_bh(&li->lock);
- spin_unlock(&fi->lock);
- mutex_unlock(&kvm->lock);
+ __inject_vm(kvm, inti);
return 0;
}
@@ -841,3 +839,207 @@ int kvm_s390_inject_vcpu(struct kvm_vcpu *vcpu,
mutex_unlock(&vcpu->kvm->lock);
return 0;
}
+
+static void clear_floating_interrupts(struct kvm *kvm)
+{
+ struct kvm_s390_float_interrupt *fi;
+ struct kvm_s390_interrupt_info *n, *inti = NULL;
+
+ mutex_lock(&kvm->lock);
+ fi = &kvm->arch.float_int;
+ spin_lock(&fi->lock);
+ list_for_each_entry_safe(inti, n, &fi->list, list) {
+ list_del(&inti->list);
+ kfree(inti);
+ }
+ atomic_set(&fi->active, 0);
+ spin_unlock(&fi->lock);
+ mutex_unlock(&kvm->lock);
+}
+
+static inline int copy_irq_to_user(struct kvm_s390_interrupt_info *inti,
+ u8 *addr)
+{
+ struct kvm_s390_irq __user *uptr = (struct kvm_s390_irq __user *) addr;
+ struct kvm_s390_irq irq = {0};
+
+ irq.type = inti->type;
+ switch (inti->type) {
+ case KVM_S390_INT_VIRTIO:
+ case KVM_S390_INT_SERVICE:
+ irq.u.ext = inti->ext;
+ break;
+ case KVM_S390_INT_IO_MIN...KVM_S390_INT_IO_MAX:
+ irq.u.io = inti->io;
+ break;
+ case KVM_S390_MCHK:
+ irq.u.mchk = inti->mchk;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ if (copy_to_user(uptr, &irq, sizeof(irq)))
+ return -EFAULT;
+
+ return 0;
+}
+
+static int get_all_floating_irqs(struct kvm *kvm, __u8 *buf, __u64 len)
+{
+ struct kvm_s390_interrupt_info *inti;
+ struct kvm_s390_float_interrupt *fi;
+ int ret = 0;
+ int n = 0;
+
+ mutex_lock(&kvm->lock);
+ fi = &kvm->arch.float_int;
+ spin_lock(&fi->lock);
+
+ list_for_each_entry(inti, &fi->list, list) {
+ if (len < sizeof(struct kvm_s390_irq)) {
+ /* signal userspace to try again */
+ ret = -ENOMEM;
+ break;
+ }
+ ret = copy_irq_to_user(inti, buf);
+ if (ret)
+ break;
+ buf += sizeof(struct kvm_s390_irq);
+ len -= sizeof(struct kvm_s390_irq);
+ n++;
+ }
+
+ spin_unlock(&fi->lock);
+ mutex_unlock(&kvm->lock);
+
+ return ret < 0 ? ret : n;
+}
+
+static int flic_get_attr(struct kvm_device *dev, struct kvm_device_attr *attr)
+{
+ int r;
+
+ switch (attr->group) {
+ case KVM_DEV_FLIC_GET_ALL_IRQS:
+ r = get_all_floating_irqs(dev->kvm, (u8 *) attr->addr,
+ attr->attr);
+ break;
+ default:
+ r = -EINVAL;
+ }
+
+ return r;
+}
+
+static inline int copy_irq_from_user(struct kvm_s390_interrupt_info *inti,
+ u64 addr)
+{
+ struct kvm_s390_irq __user *uptr = (struct kvm_s390_irq __user *) addr;
+ void *target = NULL;
+ void __user *source;
+ u64 size;
+
+ if (get_user(inti->type, (u64 __user *)addr))
+ return -EFAULT;
+
+ switch (inti->type) {
+ case KVM_S390_INT_VIRTIO:
+ case KVM_S390_INT_SERVICE:
+ target = (void *) &inti->ext;
+ source = &uptr->u.ext;
+ size = sizeof(inti->ext);
+ break;
+ case KVM_S390_INT_IO_MIN...KVM_S390_INT_IO_MAX:
+ target = (void *) &inti->io;
+ source = &uptr->u.io;
+ size = sizeof(inti->io);
+ break;
+ case KVM_S390_MCHK:
+ target = (void *) &inti->mchk;
+ source = &uptr->u.mchk;
+ size = sizeof(inti->mchk);
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ if (copy_from_user(target, source, size))
+ return -EFAULT;
+
+ return 0;
+}
+
+static int enqueue_floating_irq(struct kvm_device *dev,
+ struct kvm_device_attr *attr)
+{
+ struct kvm_s390_interrupt_info *inti = NULL;
+ int r = 0;
+ int len = attr->attr;
+
+ if (len % sizeof(struct kvm_s390_irq) != 0)
+ return -EINVAL;
+ else if (len > KVM_S390_FLIC_MAX_BUFFER)
+ return -EINVAL;
+
+ while (len >= sizeof(struct kvm_s390_irq)) {
+ inti = kzalloc(sizeof(*inti), GFP_KERNEL);
+ if (!inti)
+ return -ENOMEM;
+
+ r = copy_irq_from_user(inti, attr->addr);
+ if (r) {
+ kfree(inti);
+ return r;
+ }
+ __inject_vm(dev->kvm, inti);
+ len -= sizeof(struct kvm_s390_irq);
+ attr->addr += sizeof(struct kvm_s390_irq);
+ }
+
+ return r;
+}
+
+static int flic_set_attr(struct kvm_device *dev, struct kvm_device_attr *attr)
+{
+ int r = 0;
+
+ switch (attr->group) {
+ case KVM_DEV_FLIC_ENQUEUE:
+ r = enqueue_floating_irq(dev, attr);
+ break;
+ case KVM_DEV_FLIC_CLEAR_IRQS:
+ r = 0;
+ clear_floating_interrupts(dev->kvm);
+ break;
+ default:
+ r = -EINVAL;
+ }
+
+ return r;
+}
+
+static int flic_create(struct kvm_device *dev, u32 type)
+{
+ if (!dev)
+ return -EINVAL;
+ if (dev->kvm->arch.flic)
+ return -EINVAL;
+ dev->kvm->arch.flic = dev;
+ return 0;
+}
+
+static void flic_destroy(struct kvm_device *dev)
+{
+ dev->kvm->arch.flic = NULL;
+ kfree(dev);
+}
+
+/* s390 floating irq controller (flic) */
+struct kvm_device_ops kvm_flic_ops = {
+ .name = "kvm-flic",
+ .get_attr = flic_get_attr,
+ .set_attr = flic_set_attr,
+ .create = flic_create,
+ .destroy = flic_destroy,
+};
@@ -157,6 +157,7 @@ int kvm_dev_ioctl_check_extension(long ext)
case KVM_CAP_ENABLE_CAP:
case KVM_CAP_S390_CSS_SUPPORT:
case KVM_CAP_IOEVENTFD:
+ case KVM_CAP_DEVICE_CTRL:
r = 1;
break;
case KVM_CAP_NR_VCPUS:
@@ -1064,6 +1064,7 @@ extern struct kvm_device_ops kvm_mpic_ops;
extern struct kvm_device_ops kvm_xics_ops;
extern struct kvm_device_ops kvm_vfio_ops;
extern struct kvm_device_ops kvm_arm_vgic_v2_ops;
+extern struct kvm_device_ops kvm_flic_ops;
#ifdef CONFIG_HAVE_KVM_CPU_RELAX_INTERCEPT
@@ -918,6 +918,7 @@ struct kvm_device_attr {
#define KVM_DEV_VFIO_GROUP_ADD 1
#define KVM_DEV_VFIO_GROUP_DEL 2
#define KVM_DEV_TYPE_ARM_VGIC_V2 5
+#define KVM_DEV_TYPE_FLIC 6
/*
* ioctls for VM fds
@@ -2284,6 +2284,11 @@ static int kvm_ioctl_create_device(struct kvm *kvm,
ops = &kvm_arm_vgic_v2_ops;
break;
#endif
+#ifdef CONFIG_S390
+ case KVM_DEV_TYPE_FLIC:
+ ops = &kvm_flic_ops;
+ break;
+#endif
default:
return -ENODEV;
}