From 64d831269ccbca1fc6d739a0f3c8aa24afb43a5e Mon Sep 17 00:00:00 2001 From: Christoffer Dall Date: Tue, 19 Aug 2014 12:15:00 +0200 Subject: [PATCH] KVM: Introduce gfn_to_hva_memslot_prot To support read-only memory regions on arm and arm64, we have a need to resolve a gfn to an hva given a pointer to a memslot to avoid looping through the memslots twice and to reuse the hva error checking of gfn_to_hva_prot(), add a new gfn_to_hva_memslot_prot() function and refactor gfn_to_hva_prot() to use this function. Acked-by: Marc Zyngier Signed-off-by: Christoffer Dall --- include/linux/kvm_host.h | 2 ++ virt/kvm/kvm_main.c | 11 +++++++++-- 2 files changed, 11 insertions(+), 2 deletions(-) diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index ebd723676633..6d8a658ec174 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -528,6 +528,8 @@ struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn); unsigned long gfn_to_hva(struct kvm *kvm, gfn_t gfn); unsigned long gfn_to_hva_prot(struct kvm *kvm, gfn_t gfn, bool *writable); unsigned long gfn_to_hva_memslot(struct kvm_memory_slot *slot, gfn_t gfn); +unsigned long gfn_to_hva_memslot_prot(struct kvm_memory_slot *slot, gfn_t gfn, + bool *writable); void kvm_release_page_clean(struct page *page); void kvm_release_page_dirty(struct page *page); void kvm_set_page_accessed(struct page *page); diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 5a0817ee996e..76c92a7249c4 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -1076,9 +1076,9 @@ EXPORT_SYMBOL_GPL(gfn_to_hva); * If writable is set to false, the hva returned by this function is only * allowed to be read. */ -unsigned long gfn_to_hva_prot(struct kvm *kvm, gfn_t gfn, bool *writable) +unsigned long gfn_to_hva_memslot_prot(struct kvm_memory_slot *slot, + gfn_t gfn, bool *writable) { - struct kvm_memory_slot *slot = gfn_to_memslot(kvm, gfn); unsigned long hva = __gfn_to_hva_many(slot, gfn, NULL, false); if (!kvm_is_error_hva(hva) && writable) @@ -1087,6 +1087,13 @@ unsigned long gfn_to_hva_prot(struct kvm *kvm, gfn_t gfn, bool *writable) return hva; } +unsigned long gfn_to_hva_prot(struct kvm *kvm, gfn_t gfn, bool *writable) +{ + struct kvm_memory_slot *slot = gfn_to_memslot(kvm, gfn); + + return gfn_to_hva_memslot_prot(slot, gfn, writable); +} + static int kvm_read_hva(void *data, void __user *hva, int len) { return __copy_from_user(data, hva, len); -- 2.20.1