2019-08-29 12:49:07

by Cornelia Huck

[permalink] [raw]
Subject: [PATCH] KVM: s390: improve documentation for S390_MEM_OP

Explicitly specify the valid ranges for size and ar, and reword
buf requirements a bit.

Signed-off-by: Cornelia Huck <[email protected]>
---
supposed to go on top of "KVM: s390: Test for bad access register and
size at the start of S390_MEM_OP" (<[email protected]>)
---
Documentation/virt/kvm/api.txt | 14 ++++++++------
1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/Documentation/virt/kvm/api.txt b/Documentation/virt/kvm/api.txt
index 2d067767b617..76c9d6fdbfdb 100644
--- a/Documentation/virt/kvm/api.txt
+++ b/Documentation/virt/kvm/api.txt
@@ -3079,12 +3079,14 @@ This exception is also raised directly at the corresponding VCPU if the
flag KVM_S390_MEMOP_F_INJECT_EXCEPTION is set in the "flags" field.

The start address of the memory region has to be specified in the "gaddr"
-field, and the length of the region in the "size" field. "buf" is the buffer
-supplied by the userspace application where the read data should be written
-to for KVM_S390_MEMOP_LOGICAL_READ, or where the data that should be written
-is stored for a KVM_S390_MEMOP_LOGICAL_WRITE. "buf" is unused and can be NULL
-when KVM_S390_MEMOP_F_CHECK_ONLY is specified. "ar" designates the access
-register number to be used.
+field, and the length of the region in the "size" field (which must not
+be 0). The maximum value for "size" can be obtained by checking the
+KVM_CAP_S390_MEM_OP capability. "buf" is the buffer supplied by the
+userspace application where the read data should be written to for
+KVM_S390_MEMOP_LOGICAL_READ, or where the data that should be written is
+stored for a KVM_S390_MEMOP_LOGICAL_WRITE. When KVM_S390_MEMOP_F_CHECK_ONLY
+is specified, "buf" is unused and can be NULL. "ar" designates the access
+register number to be used; the valid range is 0..15.

The "reserved" field is meant for future extensions. It is not used by
KVM with the currently defined set of flags.
--
2.20.1


2019-08-29 12:52:03

by Thomas Huth

[permalink] [raw]
Subject: Re: [PATCH] KVM: s390: improve documentation for S390_MEM_OP

On 29/08/2019 14.47, Cornelia Huck wrote:
> Explicitly specify the valid ranges for size and ar, and reword
> buf requirements a bit.
>
> Signed-off-by: Cornelia Huck <[email protected]>
> ---
> supposed to go on top of "KVM: s390: Test for bad access register and
> size at the start of S390_MEM_OP" (<[email protected]>)
> ---
> Documentation/virt/kvm/api.txt | 14 ++++++++------
> 1 file changed, 8 insertions(+), 6 deletions(-)
>
> diff --git a/Documentation/virt/kvm/api.txt b/Documentation/virt/kvm/api.txt
> index 2d067767b617..76c9d6fdbfdb 100644
> --- a/Documentation/virt/kvm/api.txt
> +++ b/Documentation/virt/kvm/api.txt
> @@ -3079,12 +3079,14 @@ This exception is also raised directly at the corresponding VCPU if the
> flag KVM_S390_MEMOP_F_INJECT_EXCEPTION is set in the "flags" field.
>
> The start address of the memory region has to be specified in the "gaddr"
> -field, and the length of the region in the "size" field. "buf" is the buffer
> -supplied by the userspace application where the read data should be written
> -to for KVM_S390_MEMOP_LOGICAL_READ, or where the data that should be written
> -is stored for a KVM_S390_MEMOP_LOGICAL_WRITE. "buf" is unused and can be NULL
> -when KVM_S390_MEMOP_F_CHECK_ONLY is specified. "ar" designates the access
> -register number to be used.
> +field, and the length of the region in the "size" field (which must not
> +be 0). The maximum value for "size" can be obtained by checking the
> +KVM_CAP_S390_MEM_OP capability. "buf" is the buffer supplied by the
> +userspace application where the read data should be written to for
> +KVM_S390_MEMOP_LOGICAL_READ, or where the data that should be written is
> +stored for a KVM_S390_MEMOP_LOGICAL_WRITE. When KVM_S390_MEMOP_F_CHECK_ONLY
> +is specified, "buf" is unused and can be NULL. "ar" designates the access
> +register number to be used; the valid range is 0..15.
>
> The "reserved" field is meant for future extensions. It is not used by
> KVM with the currently defined set of flags.
>

Reviewed-by: Thomas Huth <[email protected]>

2019-08-29 13:40:59

by Christian Borntraeger

[permalink] [raw]
Subject: Re: [PATCH] KVM: s390: improve documentation for S390_MEM_OP

Thanks applied.

On 29.08.19 14:47, Cornelia Huck wrote:
> Explicitly specify the valid ranges for size and ar, and reword
> buf requirements a bit.
>
> Signed-off-by: Cornelia Huck <[email protected]>
> ---
> supposed to go on top of "KVM: s390: Test for bad access register and
> size at the start of S390_MEM_OP" (<[email protected]>)
> ---
> Documentation/virt/kvm/api.txt | 14 ++++++++------
> 1 file changed, 8 insertions(+), 6 deletions(-)
>
> diff --git a/Documentation/virt/kvm/api.txt b/Documentation/virt/kvm/api.txt
> index 2d067767b617..76c9d6fdbfdb 100644
> --- a/Documentation/virt/kvm/api.txt
> +++ b/Documentation/virt/kvm/api.txt
> @@ -3079,12 +3079,14 @@ This exception is also raised directly at the corresponding VCPU if the
> flag KVM_S390_MEMOP_F_INJECT_EXCEPTION is set in the "flags" field.
>
> The start address of the memory region has to be specified in the "gaddr"
> -field, and the length of the region in the "size" field. "buf" is the buffer
> -supplied by the userspace application where the read data should be written
> -to for KVM_S390_MEMOP_LOGICAL_READ, or where the data that should be written
> -is stored for a KVM_S390_MEMOP_LOGICAL_WRITE. "buf" is unused and can be NULL
> -when KVM_S390_MEMOP_F_CHECK_ONLY is specified. "ar" designates the access
> -register number to be used.
> +field, and the length of the region in the "size" field (which must not
> +be 0). The maximum value for "size" can be obtained by checking the
> +KVM_CAP_S390_MEM_OP capability. "buf" is the buffer supplied by the
> +userspace application where the read data should be written to for
> +KVM_S390_MEMOP_LOGICAL_READ, or where the data that should be written is
> +stored for a KVM_S390_MEMOP_LOGICAL_WRITE. When KVM_S390_MEMOP_F_CHECK_ONLY
> +is specified, "buf" is unused and can be NULL. "ar" designates the access
> +register number to be used; the valid range is 0..15.
>
> The "reserved" field is meant for future extensions. It is not used by
> KVM with the currently defined set of flags.
>

2019-08-29 13:59:56

by David Hildenbrand

[permalink] [raw]
Subject: Re: [PATCH] KVM: s390: improve documentation for S390_MEM_OP

On 29.08.19 14:47, Cornelia Huck wrote:
> Explicitly specify the valid ranges for size and ar, and reword
> buf requirements a bit.
>
> Signed-off-by: Cornelia Huck <[email protected]>
> ---
> supposed to go on top of "KVM: s390: Test for bad access register and
> size at the start of S390_MEM_OP" (<[email protected]>)
> ---
> Documentation/virt/kvm/api.txt | 14 ++++++++------
> 1 file changed, 8 insertions(+), 6 deletions(-)
>
> diff --git a/Documentation/virt/kvm/api.txt b/Documentation/virt/kvm/api.txt
> index 2d067767b617..76c9d6fdbfdb 100644
> --- a/Documentation/virt/kvm/api.txt
> +++ b/Documentation/virt/kvm/api.txt
> @@ -3079,12 +3079,14 @@ This exception is also raised directly at the corresponding VCPU if the
> flag KVM_S390_MEMOP_F_INJECT_EXCEPTION is set in the "flags" field.
>
> The start address of the memory region has to be specified in the "gaddr"
> -field, and the length of the region in the "size" field. "buf" is the buffer
> -supplied by the userspace application where the read data should be written
> -to for KVM_S390_MEMOP_LOGICAL_READ, or where the data that should be written
> -is stored for a KVM_S390_MEMOP_LOGICAL_WRITE. "buf" is unused and can be NULL
> -when KVM_S390_MEMOP_F_CHECK_ONLY is specified. "ar" designates the access
> -register number to be used.
> +field, and the length of the region in the "size" field (which must not
> +be 0). The maximum value for "size" can be obtained by checking the
> +KVM_CAP_S390_MEM_OP capability. "buf" is the buffer supplied by the
> +userspace application where the read data should be written to for
> +KVM_S390_MEMOP_LOGICAL_READ, or where the data that should be written is
> +stored for a KVM_S390_MEMOP_LOGICAL_WRITE. When KVM_S390_MEMOP_F_CHECK_ONLY
> +is specified, "buf" is unused and can be NULL. "ar" designates the access
> +register number to be used; the valid range is 0..15.
>
> The "reserved" field is meant for future extensions. It is not used by
> KVM with the currently defined set of flags.
>

Reviewed-by: David Hildenbrand <[email protected]>

--

Thanks,

David / dhildenb