qemu-devel
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[Qemu-devel] [PATCH 1/5] KVM: s390: Support for I/O interrupts.


From: Cornelia Huck
Subject: [Qemu-devel] [PATCH 1/5] KVM: s390: Support for I/O interrupts.
Date: Wed, 31 Oct 2012 17:24:34 +0100

Add support for handling I/O interrupts (standard, subchannel-related
ones and rudimentary adapter interrupts).

The subchannel-identifying parameters are encoded into the interrupt
type.

I/O interrupts are floating, so they can't be injected on a specific
vcpu.

Signed-off-by: Cornelia Huck <address@hidden>
---
 Documentation/virtual/kvm/api.txt |   4 ++
 arch/s390/include/asm/kvm_host.h  |   2 +
 arch/s390/kvm/interrupt.c         | 115 ++++++++++++++++++++++++++++++++++++--
 include/linux/kvm.h               |   6 ++
 4 files changed, 122 insertions(+), 5 deletions(-)

diff --git a/Documentation/virtual/kvm/api.txt 
b/Documentation/virtual/kvm/api.txt
index 4258180..b660a6e 100644
--- a/Documentation/virtual/kvm/api.txt
+++ b/Documentation/virtual/kvm/api.txt
@@ -2068,6 +2068,10 @@ KVM_S390_INT_VIRTIO (vm) - virtio external interrupt; 
external interrupt
 KVM_S390_INT_SERVICE (vm) - sclp external interrupt; sclp parameter in parm
 KVM_S390_INT_EMERGENCY (vcpu) - sigp emergency; source cpu in parm
 KVM_S390_INT_EXTERNAL_CALL (vcpu) - sigp external call; source cpu in parm
+KVM_S390_INT_IO(ai,cssid,ssid,schid) (vm) - compound value to indicate an
+    I/O interrupt (ai - adapter interrupt; cssid,ssid,schid - subchannel);
+    I/O interruption parameters in parm (subchannel) and parm64 (intparm,
+    interruption subclass)
 
 Note that the vcpu ioctl is asynchronous to vcpu execution.
 
diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h
index b784154..e47f697 100644
--- a/arch/s390/include/asm/kvm_host.h
+++ b/arch/s390/include/asm/kvm_host.h
@@ -76,6 +76,7 @@ struct kvm_s390_sie_block {
        __u64   epoch;                  /* 0x0038 */
        __u8    reserved40[4];          /* 0x0040 */
 #define LCTL_CR0       0x8000
+#define LCTL_CR6       0x0200
        __u16   lctl;                   /* 0x0044 */
        __s16   icpua;                  /* 0x0046 */
        __u32   ictl;                   /* 0x0048 */
@@ -127,6 +128,7 @@ struct kvm_vcpu_stat {
        u32 deliver_prefix_signal;
        u32 deliver_restart_signal;
        u32 deliver_program_int;
+       u32 deliver_io_int;
        u32 exit_wait_state;
        u32 instruction_stidp;
        u32 instruction_spx;
diff --git a/arch/s390/kvm/interrupt.c b/arch/s390/kvm/interrupt.c
index c30615e..070ba22 100644
--- a/arch/s390/kvm/interrupt.c
+++ b/arch/s390/kvm/interrupt.c
@@ -21,11 +21,26 @@
 #include "gaccess.h"
 #include "trace-s390.h"
 
+#define IOINT_SCHID_MASK 0x0000ffff
+#define IOINT_SSID_MASK 0x00030000
+#define IOINT_CSSID_MASK 0x03fc0000
+#define IOINT_AI_MASK 0x04000000
+
+static int is_ioint(u64 type)
+{
+       return ((type & 0xfffe0000u) != 0xfffe0000u);
+}
+
 static int psw_extint_disabled(struct kvm_vcpu *vcpu)
 {
        return !(vcpu->arch.sie_block->gpsw.mask & PSW_MASK_EXT);
 }
 
+static int psw_ioint_disabled(struct kvm_vcpu *vcpu)
+{
+       return !(vcpu->arch.sie_block->gpsw.mask & PSW_MASK_IO);
+}
+
 static int psw_interrupts_disabled(struct kvm_vcpu *vcpu)
 {
        if ((vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PER) ||
@@ -68,7 +83,18 @@ static int __interrupt_is_deliverable(struct kvm_vcpu *vcpu,
        case KVM_S390_RESTART:
                return 1;
        default:
-               BUG();
+               if (is_ioint(inti->type)) {
+                       if (psw_ioint_disabled(vcpu))
+                               return 0;
+                       if (vcpu->arch.sie_block->gcr[6] &
+                           inti->io.io_int_word)
+                               return 1;
+                       return 0;
+               } else {
+                       printk(KERN_WARNING "illegal interrupt type %llx\n",
+                              inti->type);
+                       BUG();
+               }
        }
        return 0;
 }
@@ -117,6 +143,13 @@ static void __set_intercept_indicator(struct kvm_vcpu 
*vcpu,
                __set_cpuflag(vcpu, CPUSTAT_STOP_INT);
                break;
        default:
+               if (is_ioint(inti->type)) {
+                       if (psw_ioint_disabled(vcpu))
+                               __set_cpuflag(vcpu, CPUSTAT_IO_INT);
+                       else
+                               vcpu->arch.sie_block->lctl |= LCTL_CR6;
+                       break;
+               }
                BUG();
        }
 }
@@ -298,7 +331,49 @@ static void __do_deliver_interrupt(struct kvm_vcpu *vcpu,
                break;
 
        default:
-               BUG();
+               if (is_ioint(inti->type)) {
+                       __u32 param0 = ((__u32)inti->io.subchannel_id << 16) |
+                               inti->io.subchannel_nr;
+                       __u64 param1 = ((__u64)inti->io.io_int_parm << 32) |
+                               inti->io.io_int_word;
+                       VCPU_EVENT(vcpu, 4,
+                                  "interrupt: I/O %llx", inti->type);
+                       vcpu->stat.deliver_io_int++;
+                       trace_kvm_s390_deliver_interrupt(vcpu->vcpu_id, 
inti->type,
+                                                        param0, param1);
+                       rc = put_guest_u16(vcpu, __LC_SUBCHANNEL_ID,
+                                          inti->io.subchannel_id);
+                       if (rc == -EFAULT)
+                               exception = 1;
+
+                       rc = put_guest_u16(vcpu, __LC_SUBCHANNEL_NR,
+                                          inti->io.subchannel_nr);
+                       if (rc == -EFAULT)
+                               exception = 1;
+
+                       rc = put_guest_u32(vcpu, __LC_IO_INT_PARM,
+                                          inti->io.io_int_parm);
+                       if (rc == -EFAULT)
+                               exception = 1;
+
+                       rc = put_guest_u32(vcpu, __LC_IO_INT_WORD,
+                                          inti->io.io_int_word);
+                       if (rc == -EFAULT)
+                               exception = 1;
+
+                       rc = copy_to_guest(vcpu, __LC_IO_OLD_PSW,
+                                          &vcpu->arch.sie_block->gpsw,
+                                          sizeof(psw_t));
+                       if (rc == -EFAULT)
+                               exception = 1;
+
+                       rc = copy_from_guest(vcpu, &vcpu->arch.sie_block->gpsw,
+                                            __LC_IO_NEW_PSW, sizeof(psw_t));
+                       if (rc == -EFAULT)
+                               exception = 1;
+                       break;
+               } else
+                       BUG();
        }
        if (exception) {
                printk("kvm: The guest lowcore is not mapped during interrupt "
@@ -545,7 +620,7 @@ int kvm_s390_inject_vm(struct kvm *kvm,
 {
        struct kvm_s390_local_interrupt *li;
        struct kvm_s390_float_interrupt *fi;
-       struct kvm_s390_interrupt_info *inti;
+       struct kvm_s390_interrupt_info *inti, *iter;
        int sigcpu;
 
        inti = kzalloc(sizeof(*inti), GFP_KERNEL);
@@ -569,9 +644,26 @@ int kvm_s390_inject_vm(struct kvm *kvm,
        case KVM_S390_SIGP_STOP:
        case KVM_S390_INT_EXTERNAL_CALL:
        case KVM_S390_INT_EMERGENCY:
-       default:
                kfree(inti);
                return -EINVAL;
+       default:
+               if (!is_ioint(s390int->type)) {
+                       kfree(inti);
+                       return -EINVAL;
+               }
+               if (s390int->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;
+               inti->io.io_int_word = s390int->parm64 & 0x00000000ffffffffull;
+               break;
        }
        trace_kvm_s390_inject_vm(s390int->type, s390int->parm, s390int->parm64,
                                 2);
@@ -579,7 +671,19 @@ int kvm_s390_inject_vm(struct kvm *kvm,
        mutex_lock(&kvm->lock);
        fi = &kvm->arch.float_int;
        spin_lock(&fi->lock);
-       list_add_tail(&inti->list, &fi->list);
+       if (!is_ioint(inti->type))
+               list_add_tail(&inti->list, &fi->list);
+       else {
+               /* Keep I/O interrupts sorted in isc order. */
+               list_for_each_entry(iter, &fi->list, list) {
+                       if (!is_ioint(iter->type))
+                               continue;
+                       if (iter->io.io_int_word <= inti->io.io_int_word)
+                               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) {
@@ -654,6 +758,7 @@ int kvm_s390_inject_vcpu(struct kvm_vcpu *vcpu,
        case KVM_S390_INT_VIRTIO:
        case KVM_S390_INT_SERVICE:
        default:
+               /* also includes IOINT */
                kfree(inti);
                return -EINVAL;
        }
diff --git a/include/linux/kvm.h b/include/linux/kvm.h
index 494a84c..e676940 100644
--- a/include/linux/kvm.h
+++ b/include/linux/kvm.h
@@ -401,6 +401,12 @@ struct kvm_s390_psw {
 #define KVM_S390_INT_SERVICE           0xffff2401u
 #define KVM_S390_INT_EMERGENCY         0xffff1201u
 #define KVM_S390_INT_EXTERNAL_CALL     0xffff1202u
+#define KVM_S390_INT_IO(ai,cssid,ssid,schid)   \
+       (((schid)) |                           \
+        ((ssid) << 16) |                      \
+        ((cssid) << 18) |                     \
+        ((ai) << 26))
+
 
 struct kvm_s390_interrupt {
        __u32 type;
-- 
1.7.12.4




reply via email to

[Prev in Thread] Current Thread [Next in Thread]