diff mbox series

[5/9] KVM: s390: pv: Add query dump information

Message ID 20220428130102.230790-6-frankja@linux.ibm.com (mailing list archive)
State New, archived
Headers show
Series kvm: s390: Add PV dump support | expand

Commit Message

Janosch Frank April 28, 2022, 1 p.m. UTC 
The dump API requires userspace to provide buffers into which we will
store data. The dump information added in this patch tells userspace
how big those buffers need to be.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
---
 arch/s390/kvm/kvm-s390.c | 11 +++++++++++
 include/uapi/linux/kvm.h | 12 +++++++++++-
 2 files changed, 22 insertions(+), 1 deletion(-)

Comments

Claudio Imbrenda May 9, 2022, 3:28 p.m. UTC | #1 
On Thu, 28 Apr 2022 13:00:58 +0000
Janosch Frank <frankja@linux.ibm.com> wrote:

> The dump API requires userspace to provide buffers into which we will
> store data. The dump information added in this patch tells userspace
> how big those buffers need to be.
> 
> Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
> ---
>  arch/s390/kvm/kvm-s390.c | 11 +++++++++++
>  include/uapi/linux/kvm.h | 12 +++++++++++-
>  2 files changed, 22 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
> index 23352d45a386..e327a5b8ef78 100644
> --- a/arch/s390/kvm/kvm-s390.c
> +++ b/arch/s390/kvm/kvm-s390.c
> @@ -2255,6 +2255,17 @@ static ssize_t kvm_s390_handle_pv_info(struct kvm_s390_pv_info *info)
>  
>  		return len_min;
>  	}
> +	case KVM_PV_INFO_DUMP: {
> +		len_min =  sizeof(info->header) + sizeof(info->dump);

so the output will have some zero-padded stuff at the end?

> +
> +		if (info->header.len_max < len_min)
> +			return -EINVAL;
> +
> +		info->dump.dump_cpu_buffer_len = uv_info.guest_cpu_stor_len;
> +		info->dump.dump_config_mem_buffer_per_1m = uv_info.conf_dump_storage_state_len;
> +		info->dump.dump_config_finalize_len = uv_info.conf_dump_finalize_len;
> +		return len_min;
> +	}
>  	default:
>  		return -EINVAL;
>  	}
> diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
> index 59e4fb6c7a34..2eba89d7ec29 100644
> --- a/include/uapi/linux/kvm.h
> +++ b/include/uapi/linux/kvm.h
> @@ -1647,6 +1647,13 @@ struct kvm_s390_pv_unp {
>  
>  enum pv_cmd_info_id {
>  	KVM_PV_INFO_VM,
> +	KVM_PV_INFO_DUMP,
> +};
> +
> +struct kvm_s390_pv_info_dump {
> +	__u64 dump_cpu_buffer_len;
> +	__u64 dump_config_mem_buffer_per_1m;
> +	__u64 dump_config_finalize_len;
>  };
>  
>  struct kvm_s390_pv_info_vm {
> @@ -1666,7 +1673,10 @@ struct kvm_s390_pv_info_header {
>  
>  struct kvm_s390_pv_info {
>  	struct kvm_s390_pv_info_header header;
> -	struct kvm_s390_pv_info_vm vm;
> +	union {
> +		struct kvm_s390_pv_info_dump dump;
> +		struct kvm_s390_pv_info_vm vm;
> +	};
>  };
>  
>  enum pv_cmd_id {
Janosch Frank May 10, 2022, 12:36 p.m. UTC | #2 
On 5/9/22 17:28, Claudio Imbrenda wrote:
> On Thu, 28 Apr 2022 13:00:58 +0000
> Janosch Frank <frankja@linux.ibm.com> wrote:
> 
>> The dump API requires userspace to provide buffers into which we will
>> store data. The dump information added in this patch tells userspace
>> how big those buffers need to be.
>>
>> Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
>> ---
>>   arch/s390/kvm/kvm-s390.c | 11 +++++++++++
>>   include/uapi/linux/kvm.h | 12 +++++++++++-
>>   2 files changed, 22 insertions(+), 1 deletion(-)
>>
>> diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
>> index 23352d45a386..e327a5b8ef78 100644
>> --- a/arch/s390/kvm/kvm-s390.c
>> +++ b/arch/s390/kvm/kvm-s390.c
>> @@ -2255,6 +2255,17 @@ static ssize_t kvm_s390_handle_pv_info(struct kvm_s390_pv_info *info)
>>   
>>   		return len_min;
>>   	}
>> +	case KVM_PV_INFO_DUMP: {
>> +		len_min =  sizeof(info->header) + sizeof(info->dump);
> 
> so the output will have some zero-padded stuff at the end?

In which situation?

> 
>> +
>> +		if (info->header.len_max < len_min)
>> +			return -EINVAL;
>> +
>> +		info->dump.dump_cpu_buffer_len = uv_info.guest_cpu_stor_len;
>> +		info->dump.dump_config_mem_buffer_per_1m = uv_info.conf_dump_storage_state_len;
>> +		info->dump.dump_config_finalize_len = uv_info.conf_dump_finalize_len;
>> +		return len_min;
>> +	}
>>   	default:
>>   		return -EINVAL;
>>   	}
>> diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
>> index 59e4fb6c7a34..2eba89d7ec29 100644
>> --- a/include/uapi/linux/kvm.h
>> +++ b/include/uapi/linux/kvm.h
>> @@ -1647,6 +1647,13 @@ struct kvm_s390_pv_unp {
>>   
>>   enum pv_cmd_info_id {
>>   	KVM_PV_INFO_VM,
>> +	KVM_PV_INFO_DUMP,
>> +};
>> +
>> +struct kvm_s390_pv_info_dump {
>> +	__u64 dump_cpu_buffer_len;
>> +	__u64 dump_config_mem_buffer_per_1m;
>> +	__u64 dump_config_finalize_len;
>>   };
>>   
>>   struct kvm_s390_pv_info_vm {
>> @@ -1666,7 +1673,10 @@ struct kvm_s390_pv_info_header {
>>   
>>   struct kvm_s390_pv_info {
>>   	struct kvm_s390_pv_info_header header;
>> -	struct kvm_s390_pv_info_vm vm;
>> +	union {
>> +		struct kvm_s390_pv_info_dump dump;
>> +		struct kvm_s390_pv_info_vm vm;
>> +	};
>>   };
>>   
>>   enum pv_cmd_id {
>
Claudio Imbrenda May 10, 2022, 1:28 p.m. UTC | #3 
On Tue, 10 May 2022 14:36:14 +0200
Janosch Frank <frankja@linux.ibm.com> wrote:

> On 5/9/22 17:28, Claudio Imbrenda wrote:
> > On Thu, 28 Apr 2022 13:00:58 +0000
> > Janosch Frank <frankja@linux.ibm.com> wrote:
> >   
> >> The dump API requires userspace to provide buffers into which we will
> >> store data. The dump information added in this patch tells userspace
> >> how big those buffers need to be.
> >>
> >> Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
> >> ---
> >>   arch/s390/kvm/kvm-s390.c | 11 +++++++++++
> >>   include/uapi/linux/kvm.h | 12 +++++++++++-
> >>   2 files changed, 22 insertions(+), 1 deletion(-)
> >>
> >> diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
> >> index 23352d45a386..e327a5b8ef78 100644
> >> --- a/arch/s390/kvm/kvm-s390.c
> >> +++ b/arch/s390/kvm/kvm-s390.c
> >> @@ -2255,6 +2255,17 @@ static ssize_t kvm_s390_handle_pv_info(struct kvm_s390_pv_info *info)
> >>   
> >>   		return len_min;
> >>   	}
> >> +	case KVM_PV_INFO_DUMP: {
> >> +		len_min =  sizeof(info->header) + sizeof(info->dump);  
> > 
> > so the output will have some zero-padded stuff at the end?  
> 
> In which situation?

for example when I don't read the patch correctly (oops)

> 
> >   
> >> +
> >> +		if (info->header.len_max < len_min)
> >> +			return -EINVAL;
> >> +
> >> +		info->dump.dump_cpu_buffer_len = uv_info.guest_cpu_stor_len;
> >> +		info->dump.dump_config_mem_buffer_per_1m = uv_info.conf_dump_storage_state_len;
> >> +		info->dump.dump_config_finalize_len = uv_info.conf_dump_finalize_len;
> >> +		return len_min;
> >> +	}
> >>   	default:
> >>   		return -EINVAL;
> >>   	}
> >> diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
> >> index 59e4fb6c7a34..2eba89d7ec29 100644
> >> --- a/include/uapi/linux/kvm.h
> >> +++ b/include/uapi/linux/kvm.h
> >> @@ -1647,6 +1647,13 @@ struct kvm_s390_pv_unp {
> >>   
> >>   enum pv_cmd_info_id {
> >>   	KVM_PV_INFO_VM,
> >> +	KVM_PV_INFO_DUMP,
> >> +};
> >> +
> >> +struct kvm_s390_pv_info_dump {
> >> +	__u64 dump_cpu_buffer_len;
> >> +	__u64 dump_config_mem_buffer_per_1m;
> >> +	__u64 dump_config_finalize_len;
> >>   };
> >>   
> >>   struct kvm_s390_pv_info_vm {
> >> @@ -1666,7 +1673,10 @@ struct kvm_s390_pv_info_header {
> >>   
> >>   struct kvm_s390_pv_info {
> >>   	struct kvm_s390_pv_info_header header;
> >> -	struct kvm_s390_pv_info_vm vm;
> >> +	union {
> >> +		struct kvm_s390_pv_info_dump dump;
> >> +		struct kvm_s390_pv_info_vm vm;
> >> +	};
> >>   };
> >>   
> >>   enum pv_cmd_id {  
> >   
>
diff mbox series

Patch

diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 23352d45a386..e327a5b8ef78 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -2255,6 +2255,17 @@  static ssize_t kvm_s390_handle_pv_info(struct kvm_s390_pv_info *info)
 
 		return len_min;
 	}
+	case KVM_PV_INFO_DUMP: {
+		len_min =  sizeof(info->header) + sizeof(info->dump);
+
+		if (info->header.len_max < len_min)
+			return -EINVAL;
+
+		info->dump.dump_cpu_buffer_len = uv_info.guest_cpu_stor_len;
+		info->dump.dump_config_mem_buffer_per_1m = uv_info.conf_dump_storage_state_len;
+		info->dump.dump_config_finalize_len = uv_info.conf_dump_finalize_len;
+		return len_min;
+	}
 	default:
 		return -EINVAL;
 	}
diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
index 59e4fb6c7a34..2eba89d7ec29 100644
--- a/include/uapi/linux/kvm.h
+++ b/include/uapi/linux/kvm.h
@@ -1647,6 +1647,13 @@  struct kvm_s390_pv_unp {
 
 enum pv_cmd_info_id {
 	KVM_PV_INFO_VM,
+	KVM_PV_INFO_DUMP,
+};
+
+struct kvm_s390_pv_info_dump {
+	__u64 dump_cpu_buffer_len;
+	__u64 dump_config_mem_buffer_per_1m;
+	__u64 dump_config_finalize_len;
 };
 
 struct kvm_s390_pv_info_vm {
@@ -1666,7 +1673,10 @@  struct kvm_s390_pv_info_header {
 
 struct kvm_s390_pv_info {
 	struct kvm_s390_pv_info_header header;
-	struct kvm_s390_pv_info_vm vm;
+	union {
+		struct kvm_s390_pv_info_dump dump;
+		struct kvm_s390_pv_info_vm vm;
+	};
 };
 
 enum pv_cmd_id {