From: Paul Durrant pdurrant@amazon.com
There is a pfncache unmap helper but mapping is open-coded. Arguably this is fine because mapping is done in only one place, hva_to_pfn_retry(), but adding the helper does make that function more readable.
No functional change intended.
Signed-off-by: Paul Durrant pdurrant@amazon.com Reviewed-by: David Woodhouse dwmw@amazon.co.uk --- Cc: Sean Christopherson seanjc@google.com Cc: David Woodhouse dwmw2@infradead.org Cc: Paolo Bonzini pbonzini@redhat.com
v8: - Re-work commit comment. - Fix CONFIG_HAS_IOMEM=n build. --- virt/kvm/pfncache.c | 47 ++++++++++++++++++++++++++++----------------- 1 file changed, 29 insertions(+), 18 deletions(-)
diff --git a/virt/kvm/pfncache.c b/virt/kvm/pfncache.c index 2d6aba677830..10842f1eeeae 100644 --- a/virt/kvm/pfncache.c +++ b/virt/kvm/pfncache.c @@ -96,17 +96,32 @@ bool kvm_gpc_check(struct gfn_to_pfn_cache *gpc, unsigned long len) } EXPORT_SYMBOL_GPL(kvm_gpc_check);
-static void gpc_unmap_khva(kvm_pfn_t pfn, void *khva) +static void *gpc_map(kvm_pfn_t pfn) { - /* Unmap the old pfn/page if it was mapped before. */ - if (!is_error_noslot_pfn(pfn) && khva) { - if (pfn_valid(pfn)) - kunmap(pfn_to_page(pfn)); + if (pfn_valid(pfn)) + return kmap(pfn_to_page(pfn)); + #ifdef CONFIG_HAS_IOMEM - else - memunmap(khva); + return memremap(pfn_to_hpa(pfn), PAGE_SIZE, MEMREMAP_WB); +#else + return NULL; #endif +} + +static void gpc_unmap(kvm_pfn_t pfn, void *khva) +{ + /* Unmap the old pfn/page if it was mapped before. */ + if (is_error_noslot_pfn(pfn) || !khva) + return; + + if (pfn_valid(pfn)) { + kunmap(pfn_to_page(pfn)); + return; } + +#ifdef CONFIG_HAS_IOMEM + memunmap(khva); +#endif }
static inline bool mmu_notifier_retry_cache(struct kvm *kvm, unsigned long mmu_seq) @@ -175,7 +190,7 @@ static kvm_pfn_t hva_to_pfn_retry(struct gfn_to_pfn_cache *gpc) * the existing mapping and didn't create a new one. */ if (new_khva != old_khva) - gpc_unmap_khva(new_pfn, new_khva); + gpc_unmap(new_pfn, new_khva);
kvm_release_pfn_clean(new_pfn);
@@ -193,15 +208,11 @@ static kvm_pfn_t hva_to_pfn_retry(struct gfn_to_pfn_cache *gpc) * too must be done outside of gpc->lock! */ if (gpc->usage & KVM_HOST_USES_PFN) { - if (new_pfn == gpc->pfn) { + if (new_pfn == gpc->pfn) new_khva = old_khva; - } else if (pfn_valid(new_pfn)) { - new_khva = kmap(pfn_to_page(new_pfn)); -#ifdef CONFIG_HAS_IOMEM - } else { - new_khva = memremap(pfn_to_hpa(new_pfn), PAGE_SIZE, MEMREMAP_WB); -#endif - } + else + new_khva = gpc_map(new_pfn); + if (!new_khva) { kvm_release_pfn_clean(new_pfn); goto out_error; @@ -326,7 +337,7 @@ static int __kvm_gpc_refresh(struct gfn_to_pfn_cache *gpc, gpa_t gpa, mutex_unlock(&gpc->refresh_lock);
if (unmap_old) - gpc_unmap_khva(old_pfn, old_khva); + gpc_unmap(old_pfn, old_khva);
return ret; } @@ -412,7 +423,7 @@ void kvm_gpc_deactivate(struct gfn_to_pfn_cache *gpc) list_del(&gpc->list); spin_unlock(&kvm->gpc_lock);
- gpc_unmap_khva(old_pfn, old_khva); + gpc_unmap(old_pfn, old_khva); } } EXPORT_SYMBOL_GPL(kvm_gpc_deactivate);