Hi Marc,
On 2021/6/2 18:22, Marc Zyngier wrote:
On Thu, 15 Apr 2021 12:50:30 +0100,
Yanan Wang <wangyanan55@xxxxxxxxxx> wrote:
We want to move I-cache maintenance for the guest to the stage-2
page table code for performance improvement. Before it can work,
we should first make function invalidate_icache_range available
to non-VHE EL2 to avoid compiling or program running error, as
pgtable.c is now linked into the non-VHE EL2 code for pKVM mode.
In this patch, we only introduce symbol of invalidate_icache_range
with no real functionality in nvhe/cache.S, because there haven't
been situations found currently where I-cache maintenance is also
needed in non-VHE EL2 for pKVM mode.
Signed-off-by: Yanan Wang <wangyanan55@xxxxxxxxxx>
---
arch/arm64/kvm/hyp/nvhe/cache.S | 11 +++++++++++
1 file changed, 11 insertions(+)
diff --git a/arch/arm64/kvm/hyp/nvhe/cache.S b/arch/arm64/kvm/hyp/nvhe/cache.S
index 36cef6915428..a125ec9aeed2 100644
--- a/arch/arm64/kvm/hyp/nvhe/cache.S
+++ b/arch/arm64/kvm/hyp/nvhe/cache.S
@@ -11,3 +11,14 @@ SYM_FUNC_START_PI(__flush_dcache_area)
dcache_by_line_op civac, sy, x0, x1, x2, x3
ret
SYM_FUNC_END_PI(__flush_dcache_area)
+
+/*
+ * invalidate_icache_range(start,end)
+ *
+ * Ensure that the I cache is invalid within specified region.
+ *
+ * - start - virtual start address of region
+ * - end - virtual end address of region
+ */
+SYM_FUNC_START(invalidate_icache_range)
+SYM_FUNC_END(invalidate_icache_range)
This is a good indication that something is really wrong.
If you were to provide cache management callbacks as part of the
mm_ops themselves (or a similar abstraction), you wouldn't have to do
these things.
Yes, we definitely don't need this work if we do that.
Thanks,
Yanan
M.
