KVM: s390: Introduce new structures

This patch adds new structures and updates some existing ones to
provide the base for Extended SCA functionality.

The old sca_* structures were renamed to bsca_* to keep things uniform.

The access to fields of SIGP controls were turned into bitfields instead
of hardcoded bitmasks.

Signed-off-by: Eugene (jno) Dvurechenski <jno@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>

diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h
index efaac2c3bb77a028a748de19820cd40ee528c0a0..923b13df43a745d95ccc714955abc3172b1cacaa 100644 (file)
--- a/arch/s390/include/asm/kvm_host.h
+++ b/arch/s390/include/asm/kvm_host.h
@@ -25,7 +25,9 @@
 #include <asm/fpu/api.h>
 #include <asm/isc.h>
 
-#define KVM_MAX_VCPUS 64
+#define KVM_S390_BSCA_CPU_SLOTS 64
+#define KVM_S390_ESCA_CPU_SLOTS 248
+#define KVM_MAX_VCPUS KVM_S390_BSCA_CPU_SLOTS
 #define KVM_USER_MEM_SLOTS 32
 
 /*
@@ -40,9 +42,34 @@
 #define SIGP_CTRL_C            0x80
 #define SIGP_CTRL_SCN_MASK     0x3f
 
-struct sca_entry {
+union bsca_sigp_ctrl {
+       __u8 value;
+       struct {
+               __u8 c : 1;
+               __u8 r : 1;
+               __u8 scn : 6;
+       };
+} __packed;
+
+union esca_sigp_ctrl {
+       __u16 value;
+       struct {
+               __u8 c : 1;
+               __u8 reserved: 7;
+               __u8 scn;
+       };
+} __packed;
+
+struct esca_entry {
+       union esca_sigp_ctrl sigp_ctrl;
+       __u16   reserved1[3];
+       __u64   sda;
+       __u64   reserved2[6];
+} __packed;
+
+struct bsca_entry {
        __u8    reserved0;
-       __u8    sigp_ctrl;
+       union bsca_sigp_ctrl    sigp_ctrl;
        __u16   reserved[3];
        __u64   sda;
        __u64   reserved2[2];
@@ -57,14 +84,22 @@ union ipte_control {
        };
 };
 
-struct sca_block {
+struct bsca_block {
        union ipte_control ipte_control;
        __u64   reserved[5];
        __u64   mcn;
        __u64   reserved2;
-       struct sca_entry cpu[64];
+       struct bsca_entry cpu[KVM_S390_BSCA_CPU_SLOTS];
 } __attribute__((packed));
 
+struct esca_block {
+       union ipte_control ipte_control;
+       __u64   reserved1[7];
+       __u64   mcn[4];
+       __u64   reserved2[20];
+       struct esca_entry cpu[KVM_S390_ESCA_CPU_SLOTS];
+} __packed;
+
 #define CPUSTAT_STOPPED    0x80000000
 #define CPUSTAT_WAIT       0x10000000
 #define CPUSTAT_ECALL_PEND 0x08000000
@@ -585,7 +620,7 @@ struct kvm_s390_crypto_cb {
 };
 
 struct kvm_arch{
-       struct sca_block *sca;
+       struct bsca_block *sca;
        debug_info_t *dbf;
        struct kvm_s390_float_interrupt float_int;
        struct kvm_device *flic;

diff --git a/arch/s390/kvm/interrupt.c b/arch/s390/kvm/interrupt.c
index 2a4718af9dcfad9d91ea57407169336dcd1cab76..aa221a48cc7c12060126617605d88d8e19c6a562 100644 (file)
--- a/arch/s390/kvm/interrupt.c
+++ b/arch/s390/kvm/interrupt.c
@@ -37,25 +37,32 @@
 /* handle external calls via sigp interpretation facility */
 static int sca_ext_call_pending(struct kvm_vcpu *vcpu, int *src_id)
 {
-       struct sca_block *sca = vcpu->kvm->arch.sca;
-       uint8_t sigp_ctrl = sca->cpu[vcpu->vcpu_id].sigp_ctrl;
+       struct bsca_block *sca = vcpu->kvm->arch.sca;
+       union bsca_sigp_ctrl sigp_ctrl = sca->cpu[vcpu->vcpu_id].sigp_ctrl;
 
        if (src_id)
-               *src_id = sigp_ctrl & SIGP_CTRL_SCN_MASK;
+               *src_id = sigp_ctrl.scn;
 
-       return sigp_ctrl & SIGP_CTRL_C &&
+       return sigp_ctrl.c &&
                atomic_read(&vcpu->arch.sie_block->cpuflags) &
                        CPUSTAT_ECALL_PEND;
 }
 
 static int sca_inject_ext_call(struct kvm_vcpu *vcpu, int src_id)
 {
-       struct sca_block *sca = vcpu->kvm->arch.sca;
-       uint8_t *sigp_ctrl = &(sca->cpu[vcpu->vcpu_id].sigp_ctrl);
-       uint8_t new_val = SIGP_CTRL_C | (src_id & SIGP_CTRL_SCN_MASK);
-       uint8_t old_val = *sigp_ctrl & ~SIGP_CTRL_C;
+       int expect, rc;
+       struct bsca_block *sca = vcpu->kvm->arch.sca;
+       union bsca_sigp_ctrl *sigp_ctrl = &(sca->cpu[vcpu->vcpu_id].sigp_ctrl);
+       union bsca_sigp_ctrl new_val = {0}, old_val = *sigp_ctrl;
 
-       if (cmpxchg(sigp_ctrl, old_val, new_val) != old_val) {
+       new_val.scn = src_id;
+       new_val.c = 1;
+       old_val.c = 0;
+
+       expect = old_val.value;
+       rc = cmpxchg(&sigp_ctrl->value, old_val.value, new_val.value);
+
+       if (rc != expect) {
                /* another external call is pending */
                return -EBUSY;
        }
@@ -65,12 +72,12 @@ static int sca_inject_ext_call(struct kvm_vcpu *vcpu, int src_id)
 
 static void sca_clear_ext_call(struct kvm_vcpu *vcpu)
 {
-       struct sca_block *sca = vcpu->kvm->arch.sca;
+       struct bsca_block *sca = vcpu->kvm->arch.sca;
        struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
-       uint8_t *sigp_ctrl = &(sca->cpu[vcpu->vcpu_id].sigp_ctrl);
+       union bsca_sigp_ctrl *sigp_ctrl = &(sca->cpu[vcpu->vcpu_id].sigp_ctrl);
 
        atomic_andnot(CPUSTAT_ECALL_PEND, li->cpuflags);
-       *sigp_ctrl = 0;
+       sigp_ctrl->value = 0;
 }
 
 int psw_extint_disabled(struct kvm_vcpu *vcpu)

diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 8ddd48848a8301411adcdb8e8d9c33b8c7d24c60..c2683529b25c97dab521490896f0645105342a12 100644 (file)
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -1100,14 +1100,15 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
 
        rc = -ENOMEM;
 
-       kvm->arch.sca = (struct sca_block *) get_zeroed_page(GFP_KERNEL);
+       kvm->arch.sca = (struct bsca_block *) get_zeroed_page(GFP_KERNEL);
        if (!kvm->arch.sca)
                goto out_err;
        spin_lock(&kvm_lock);
        sca_offset += 16;
-       if (sca_offset + sizeof(struct sca_block) > PAGE_SIZE)
+       if (sca_offset + sizeof(struct bsca_block) > PAGE_SIZE)
                sca_offset = 0;
-       kvm->arch.sca = (struct sca_block *) ((char *) kvm->arch.sca + sca_offset);
+       kvm->arch.sca = (struct bsca_block *)
+                       ((char *) kvm->arch.sca + sca_offset);
        spin_unlock(&kvm_lock);
 
        sprintf(debug_name, "kvm-%u", current->pid);
@@ -1190,9 +1191,8 @@ void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
        trace_kvm_s390_destroy_vcpu(vcpu->vcpu_id);
        kvm_s390_clear_local_irqs(vcpu);
        kvm_clear_async_pf_completion_queue(vcpu);
-       if (!kvm_is_ucontrol(vcpu->kvm)) {
+       if (!kvm_is_ucontrol(vcpu->kvm))
                sca_del_vcpu(vcpu);
-       }
        smp_mb();
 
        if (kvm_is_ucontrol(vcpu->kvm))
@@ -1249,7 +1249,7 @@ static int __kvm_ucontrol_vcpu_init(struct kvm_vcpu *vcpu)
 
 static void sca_del_vcpu(struct kvm_vcpu *vcpu)
 {
-       struct sca_block *sca = vcpu->kvm->arch.sca;
+       struct bsca_block *sca = vcpu->kvm->arch.sca;
 
        clear_bit_inv(vcpu->vcpu_id, (unsigned long *) &sca->mcn);
        if (sca->cpu[vcpu->vcpu_id].sda == (__u64) vcpu->arch.sie_block)
@@ -1259,7 +1259,7 @@ static void sca_del_vcpu(struct kvm_vcpu *vcpu)
 static void sca_add_vcpu(struct kvm_vcpu *vcpu, struct kvm *kvm,
                        unsigned int id)
 {
-       struct sca_block *sca = kvm->arch.sca;
+       struct bsca_block *sca = kvm->arch.sca;
 
        if (!sca->cpu[id].sda)
                sca->cpu[id].sda = (__u64) vcpu->arch.sie_block;

diff --git a/arch/s390/kvm/kvm-s390.h b/arch/s390/kvm/kvm-s390.h
index 844f711972f9ac19ed446db32b78a8b42717a040..df1abada1f36dfc3579ab6ff2ef45c7db828490b 100644 (file)
--- a/arch/s390/kvm/kvm-s390.h
+++ b/arch/s390/kvm/kvm-s390.h
@@ -343,6 +343,8 @@ void kvm_s390_handle_per_event(struct kvm_vcpu *vcpu);
 /* support for Basic/Extended SCA handling */
 static inline union ipte_control *kvm_s390_get_ipte_control(struct kvm *kvm)
 {
-       return &kvm->arch.sca->ipte_control;
+       struct bsca_block *sca = kvm->arch.sca; /* SCA version doesn't matter */
+
+       return &sca->ipte_control;
 }
 #endif