Message ID | 20231109210325.3806151-3-amoorthy@google.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Series | Improve KVM + userfaultfd performance via KVM_MEMORY_FAULT_EXITs on stage-2 faults | expand |
Same "Documentation" issue. And the purpose of the change isn't to add docstrings, the purpose is to clarify the goofy/strange parameters: KVM: Add comment to clarify param usage for __kvm{read,_write}_guest_page() On Thu, Nov 09, 2023, Anish Moorthy wrote: > The (gfn, data, offset, len) order of parameters is a little strange > since "offset" applies to "gfn" rather than to "data". Add docstrings to s/docstrings/function comments/. This change has value and impact even if the kernel suddenly stops generating documentation from code. > make things perfectly clear. > > Signed-off-by: Anish Moorthy <amoorthy@google.com> > --- > virt/kvm/kvm_main.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c > index 687374138cfd..f521b6fd808f 100644 > --- a/virt/kvm/kvm_main.c > +++ b/virt/kvm/kvm_main.c > @@ -3328,6 +3328,7 @@ static int next_segment(unsigned long len, int offset) > return len; > } > > +/* Copy @len bytes from guest memory at '(@gfn * PAGE_SIZE) + @offset' to @data */ > static int __kvm_read_guest_page(struct kvm_memory_slot *slot, gfn_t gfn, > void *data, int offset, int len) > { > @@ -3429,6 +3430,7 @@ int kvm_vcpu_read_guest_atomic(struct kvm_vcpu *vcpu, gpa_t gpa, > } > EXPORT_SYMBOL_GPL(kvm_vcpu_read_guest_atomic); > > +/* Copy @len bytes from @data into guest memory at '(@gfn * PAGE_SIZE) + @offset' */ > static int __kvm_write_guest_page(struct kvm *kvm, > struct kvm_memory_slot *memslot, gfn_t gfn, > const void *data, int offset, int len) > -- > 2.42.0.869.gea05f2083d-goog >
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 687374138cfd..f521b6fd808f 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -3328,6 +3328,7 @@ static int next_segment(unsigned long len, int offset) return len; } +/* Copy @len bytes from guest memory at '(@gfn * PAGE_SIZE) + @offset' to @data */ static int __kvm_read_guest_page(struct kvm_memory_slot *slot, gfn_t gfn, void *data, int offset, int len) { @@ -3429,6 +3430,7 @@ int kvm_vcpu_read_guest_atomic(struct kvm_vcpu *vcpu, gpa_t gpa, } EXPORT_SYMBOL_GPL(kvm_vcpu_read_guest_atomic); +/* Copy @len bytes from @data into guest memory at '(@gfn * PAGE_SIZE) + @offset' */ static int __kvm_write_guest_page(struct kvm *kvm, struct kvm_memory_slot *memslot, gfn_t gfn, const void *data, int offset, int len)
The (gfn, data, offset, len) order of parameters is a little strange since "offset" applies to "gfn" rather than to "data". Add docstrings to make things perfectly clear. Signed-off-by: Anish Moorthy <amoorthy@google.com> --- virt/kvm/kvm_main.c | 2 ++ 1 file changed, 2 insertions(+)