diff mbox series

[v6,08/18] s390x: Add SIDA memory ops

Message ID 20200304114231.23493-9-frankja@linux.ibm.com (mailing list archive)
State New, archived
Headers show
Series s390x: Protected Virtualization support | expand

Commit Message

Janosch Frank March 4, 2020, 11:42 a.m. UTC 
Protected guests save the instruction control blocks in the SIDA
instead of QEMU/KVM directly accessing the guest's memory.

Let's introduce new functions to access the SIDA.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
---
 linux-headers/linux/kvm.h |  2 ++
 target/s390x/cpu.h        |  7 ++++++-
 target/s390x/kvm.c        | 25 +++++++++++++++++++++++++
 target/s390x/kvm_s390x.h  |  2 ++
 target/s390x/mmu_helper.c | 14 ++++++++++++++
 5 files changed, 49 insertions(+), 1 deletion(-)

Comments

David Hildenbrand March 4, 2020, 5:39 p.m. UTC | #1 
On 04.03.20 12:42, Janosch Frank wrote:
> Protected guests save the instruction control blocks in the SIDA
> instead of QEMU/KVM directly accessing the guest's memory.
> 
> Let's introduce new functions to access the SIDA.

"The new memops are available with KVM_CAP_S390_PROTECTED, so let's
check for that."

> 
> Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
> ---
>  linux-headers/linux/kvm.h |  2 ++
>  target/s390x/cpu.h        |  7 ++++++-
>  target/s390x/kvm.c        | 25 +++++++++++++++++++++++++
>  target/s390x/kvm_s390x.h  |  2 ++
>  target/s390x/mmu_helper.c | 14 ++++++++++++++
>  5 files changed, 49 insertions(+), 1 deletion(-)
> 
> diff --git a/linux-headers/linux/kvm.h b/linux-headers/linux/kvm.h
> index e36f761194..c30344ab00 100644
> --- a/linux-headers/linux/kvm.h
> +++ b/linux-headers/linux/kvm.h
> @@ -483,6 +483,8 @@ struct kvm_s390_mem_op {
>  /* types for kvm_s390_mem_op->op */
>  #define KVM_S390_MEMOP_LOGICAL_READ	0
>  #define KVM_S390_MEMOP_LOGICAL_WRITE	1
> +#define KVM_S390_MEMOP_SIDA_READ	2
> +#define KVM_S390_MEMOP_SIDA_WRITE	3
>  /* flags for kvm_s390_mem_op->flags */
>  #define KVM_S390_MEMOP_F_CHECK_ONLY		(1ULL << 0)
>  #define KVM_S390_MEMOP_F_INJECT_EXCEPTION	(1ULL << 1)

This should go into the header sync.

[...]

> index 7e4d9d267c..2578c838f8 100644
> --- a/target/s390x/cpu.h
> +++ b/target/s390x/cpu.h
> @@ -824,7 +824,12 @@ int s390_cpu_virt_mem_rw(S390CPU *cpu, vaddr laddr, uint8_t ar, void *hostbuf,
>  #define s390_cpu_virt_mem_check_write(cpu, laddr, ar, len)   \
>          s390_cpu_virt_mem_rw(cpu, laddr, ar, NULL, len, true)
>  void s390_cpu_virt_mem_handle_exc(S390CPU *cpu, uintptr_t ra);
> -
> +int s390_cpu_pv_mem_rw(S390CPU *cpu, unsigned int offset,  void *hostbuf,

double space after "offset,"

[...]

>  
> +int s390_cpu_pv_mem_rw(S390CPU *cpu, unsigned int offset, void *hostbuf,
> +                       int len, bool is_write)
> +{
> +    int ret;
> +
> +    if (kvm_enabled()) {
> +        ret = kvm_s390_mem_op_pv(cpu, offset, hostbuf, len, is_write);
> +    } else {
> +        /* Protected Virtualization is a KVM/Hardware only feature */
> +        g_assert_not_reached();
> +    }
> +    return ret;
> +}


I suspect nobody will ever check the return value, correct?

With the things changed

Reviewed-by: David Hildenbrand <david@redhat.com>
Janosch Frank March 5, 2020, 9:23 a.m. UTC | #2 
On 3/4/20 6:39 PM, David Hildenbrand wrote:
> On 04.03.20 12:42, Janosch Frank wrote:
>> Protected guests save the instruction control blocks in the SIDA
>> instead of QEMU/KVM directly accessing the guest's memory.
>>
>> Let's introduce new functions to access the SIDA.
> 
> "The new memops are available with KVM_CAP_S390_PROTECTED, so let's
> check for that."

Ack

> 
>>
>> Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
>> ---
>>  linux-headers/linux/kvm.h |  2 ++
>>  target/s390x/cpu.h        |  7 ++++++-
>>  target/s390x/kvm.c        | 25 +++++++++++++++++++++++++
>>  target/s390x/kvm_s390x.h  |  2 ++
>>  target/s390x/mmu_helper.c | 14 ++++++++++++++
>>  5 files changed, 49 insertions(+), 1 deletion(-)
>>
>> diff --git a/linux-headers/linux/kvm.h b/linux-headers/linux/kvm.h
>> index e36f761194..c30344ab00 100644
>> --- a/linux-headers/linux/kvm.h
>> +++ b/linux-headers/linux/kvm.h
>> @@ -483,6 +483,8 @@ struct kvm_s390_mem_op {
>>  /* types for kvm_s390_mem_op->op */
>>  #define KVM_S390_MEMOP_LOGICAL_READ	0
>>  #define KVM_S390_MEMOP_LOGICAL_WRITE	1
>> +#define KVM_S390_MEMOP_SIDA_READ	2
>> +#define KVM_S390_MEMOP_SIDA_WRITE	3
>>  /* flags for kvm_s390_mem_op->flags */
>>  #define KVM_S390_MEMOP_F_CHECK_ONLY		(1ULL << 0)
>>  #define KVM_S390_MEMOP_F_INJECT_EXCEPTION	(1ULL << 1)
> 
> This should go into the header sync.

Ack

> 
> [...]
> 
>> index 7e4d9d267c..2578c838f8 100644
>> --- a/target/s390x/cpu.h
>> +++ b/target/s390x/cpu.h
>> @@ -824,7 +824,12 @@ int s390_cpu_virt_mem_rw(S390CPU *cpu, vaddr laddr, uint8_t ar, void *hostbuf,
>>  #define s390_cpu_virt_mem_check_write(cpu, laddr, ar, len)   \
>>          s390_cpu_virt_mem_rw(cpu, laddr, ar, NULL, len, true)
>>  void s390_cpu_virt_mem_handle_exc(S390CPU *cpu, uintptr_t ra);
>> -
>> +int s390_cpu_pv_mem_rw(S390CPU *cpu, unsigned int offset,  void *hostbuf,
> 
> double space after "offset,"

Ack

> 
> [...]
> 
>>  
>> +int s390_cpu_pv_mem_rw(S390CPU *cpu, unsigned int offset, void *hostbuf,
>> +                       int len, bool is_write)
>> +{
>> +    int ret;
>> +
>> +    if (kvm_enabled()) {
>> +        ret = kvm_s390_mem_op_pv(cpu, offset, hostbuf, len, is_write);
>> +    } else {
>> +        /* Protected Virtualization is a KVM/Hardware only feature */
>> +        g_assert_not_reached();
>> +    }
>> +    return ret;
>> +}
> 
> 
> I suspect nobody will ever check the return value, correct?
> 
> With the things changed
> 
> Reviewed-by: David Hildenbrand <david@redhat.com>

Thanks!

>
diff mbox series

Patch

diff --git a/linux-headers/linux/kvm.h b/linux-headers/linux/kvm.h
index e36f761194..c30344ab00 100644
--- a/linux-headers/linux/kvm.h
+++ b/linux-headers/linux/kvm.h
@@ -483,6 +483,8 @@  struct kvm_s390_mem_op {
 /* types for kvm_s390_mem_op->op */
 #define KVM_S390_MEMOP_LOGICAL_READ	0
 #define KVM_S390_MEMOP_LOGICAL_WRITE	1
+#define KVM_S390_MEMOP_SIDA_READ	2
+#define KVM_S390_MEMOP_SIDA_WRITE	3
 /* flags for kvm_s390_mem_op->flags */
 #define KVM_S390_MEMOP_F_CHECK_ONLY		(1ULL << 0)
 #define KVM_S390_MEMOP_F_INJECT_EXCEPTION	(1ULL << 1)
diff --git a/target/s390x/cpu.h b/target/s390x/cpu.h
index 7e4d9d267c..2578c838f8 100644
--- a/target/s390x/cpu.h
+++ b/target/s390x/cpu.h
@@ -824,7 +824,12 @@  int s390_cpu_virt_mem_rw(S390CPU *cpu, vaddr laddr, uint8_t ar, void *hostbuf,
 #define s390_cpu_virt_mem_check_write(cpu, laddr, ar, len)   \
         s390_cpu_virt_mem_rw(cpu, laddr, ar, NULL, len, true)
 void s390_cpu_virt_mem_handle_exc(S390CPU *cpu, uintptr_t ra);
-
+int s390_cpu_pv_mem_rw(S390CPU *cpu, unsigned int offset,  void *hostbuf,
+                       int len, bool is_write);
+#define s390_cpu_pv_mem_read(cpu, offset, dest, len)    \
+        s390_cpu_pv_mem_rw(cpu, offset, dest, len, false)
+#define s390_cpu_pv_mem_write(cpu, offset, dest, len)       \
+        s390_cpu_pv_mem_rw(cpu, offset, dest, len, true)
 
 /* sigp.c */
 int s390_cpu_restart(S390CPU *cpu);
diff --git a/target/s390x/kvm.c b/target/s390x/kvm.c
index eec0b92479..cdcd538b4f 100644
--- a/target/s390x/kvm.c
+++ b/target/s390x/kvm.c
@@ -154,6 +154,7 @@  static int cap_ri;
 static int cap_gs;
 static int cap_hpage_1m;
 static int cap_vcpu_resets;
+static int cap_protected;
 
 static int active_cmma;
 
@@ -346,6 +347,7 @@  int kvm_arch_init(MachineState *ms, KVMState *s)
     cap_mem_op = kvm_check_extension(s, KVM_CAP_S390_MEM_OP);
     cap_s390_irq = kvm_check_extension(s, KVM_CAP_S390_INJECT_IRQ);
     cap_vcpu_resets = kvm_check_extension(s, KVM_CAP_S390_VCPU_RESETS);
+    cap_protected = kvm_check_extension(s, KVM_CAP_S390_PROTECTED);
 
     if (!kvm_check_extension(s, KVM_CAP_S390_GMAP)
         || !kvm_check_extension(s, KVM_CAP_S390_COW)) {
@@ -846,6 +848,29 @@  int kvm_s390_mem_op(S390CPU *cpu, vaddr addr, uint8_t ar, void *hostbuf,
     return ret;
 }
 
+int kvm_s390_mem_op_pv(S390CPU *cpu, uint64_t offset, void *hostbuf,
+                       int len, bool is_write)
+{
+    struct kvm_s390_mem_op mem_op = {
+        .sida_offset = offset,
+        .size = len,
+        .op = is_write ? KVM_S390_MEMOP_SIDA_WRITE
+                       : KVM_S390_MEMOP_SIDA_READ,
+        .buf = (uint64_t)hostbuf,
+    };
+    int ret;
+
+    if (!cap_mem_op || !cap_protected) {
+        return -ENOSYS;
+    }
+
+    ret = kvm_vcpu_ioctl(CPU(cpu), KVM_S390_MEM_OP, &mem_op);
+    if (ret < 0) {
+        error_report("KVM_S390_MEM_OP failed: %s", strerror(-ret));
+    }
+    return ret;
+}
+
 /*
  * Legacy layout for s390:
  * Older S390 KVM requires the topmost vma of the RAM to be
diff --git a/target/s390x/kvm_s390x.h b/target/s390x/kvm_s390x.h
index 0b21789796..9c38f6ccce 100644
--- a/target/s390x/kvm_s390x.h
+++ b/target/s390x/kvm_s390x.h
@@ -19,6 +19,8 @@  void kvm_s390_vcpu_interrupt(S390CPU *cpu, struct kvm_s390_irq *irq);
 void kvm_s390_access_exception(S390CPU *cpu, uint16_t code, uint64_t te_code);
 int kvm_s390_mem_op(S390CPU *cpu, vaddr addr, uint8_t ar, void *hostbuf,
                     int len, bool is_write);
+int kvm_s390_mem_op_pv(S390CPU *cpu, vaddr addr, void *hostbuf, int len,
+                       bool is_write);
 void kvm_s390_program_interrupt(S390CPU *cpu, uint16_t code);
 int kvm_s390_set_cpu_state(S390CPU *cpu, uint8_t cpu_state);
 void kvm_s390_vcpu_interrupt_pre_save(S390CPU *cpu);
diff --git a/target/s390x/mmu_helper.c b/target/s390x/mmu_helper.c
index 0be2f300bb..7d9f3059cd 100644
--- a/target/s390x/mmu_helper.c
+++ b/target/s390x/mmu_helper.c
@@ -474,6 +474,20 @@  static int translate_pages(S390CPU *cpu, vaddr addr, int nr_pages,
     return 0;
 }
 
+int s390_cpu_pv_mem_rw(S390CPU *cpu, unsigned int offset, void *hostbuf,
+                       int len, bool is_write)
+{
+    int ret;
+
+    if (kvm_enabled()) {
+        ret = kvm_s390_mem_op_pv(cpu, offset, hostbuf, len, is_write);
+    } else {
+        /* Protected Virtualization is a KVM/Hardware only feature */
+        g_assert_not_reached();
+    }
+    return ret;
+}
+
 /**
  * s390_cpu_virt_mem_rw:
  * @laddr:     the logical start address