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 <cohuck@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Link: https://lkml.kernel.org/r/20190829124746.28665-1-cohuck@redhat.com
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
This commit is contained in:
Cornelia Huck 2019-08-29 14:47:46 +02:00 committed by Christian Borntraeger
parent a13b03bbb4
commit b4d863c302

View File

@ -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.