linux-kernel - [PATCH] KVM: use folio_nr_pages() instead of shift operation

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Message-Id: <20251004030210.49080-1-pedrodemargomes@gmail.com>
Date: Sat,  4 Oct 2025 00:02:10 -0300
From: Pedro Demarchi Gomes <pedrodemargomes@...il.com>
To: Paolo Bonzini <pbonzini@...hat.com>
Cc: kvm@...r.kernel.org,
	linux-kernel@...r.kernel.org,
	Pedro Demarchi Gomes <pedrodemargomes@...il.com>
Subject: [PATCH] KVM: use folio_nr_pages() instead of shift operation

folio_nr_pages() is a faster helper function to get the number of pages when
NR_PAGES_IN_LARGE_FOLIO is enabled.

Signed-off-by: Pedro Demarchi Gomes <pedrodemargomes@...il.com>
---
 virt/kvm/guest_memfd.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/virt/kvm/guest_memfd.c b/virt/kvm/guest_memfd.c
index 7d85cc33c0bb..5fc5475cf826 100644
--- a/virt/kvm/guest_memfd.c
+++ b/virt/kvm/guest_memfd.c
@@ -77,9 +77,9 @@ static int kvm_gmem_prepare_folio(struct kvm *kvm, struct kvm_memory_slot *slot,
 	 * The order will be passed when creating the guest_memfd, and
 	 * checked when creating memslots.
 	 */
-	WARN_ON(!IS_ALIGNED(slot->gmem.pgoff, 1 << folio_order(folio)));
+	WARN_ON(!IS_ALIGNED(slot->gmem.pgoff, folio_nr_pages(folio)));
 	index = gfn - slot->base_gfn + slot->gmem.pgoff;
-	index = ALIGN_DOWN(index, 1 << folio_order(folio));
+	index = ALIGN_DOWN(index, folio_nr_pages(folio));
 	r = __kvm_gmem_prepare_folio(kvm, slot, index, folio);
 	if (!r)
 		kvm_gmem_mark_prepared(folio);
-- 
2.39.5