[v3,25/32] KVM: arm64: Sort the hypervisor memblocks

Commit Message

Quentin Perret March 2, 2021, 2:59 p.m. UTC

We will soon need to check if a Physical Address belongs to a memblock
at EL2, so make sure to sort them so this can be done efficiently.

Signed-off-by: Quentin Perret <[e-mail]>
---
 arch/arm64/kvm/hyp/reserved_mem.c | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

Comments

Will Deacon March 4, 2021, 7:51 p.m. UTC | #1

On Tue, Mar 02, 2021 at 02:59:55PM +0000, Quentin Perret wrote:
> We will soon need to check if a Physical Address belongs to a memblock
> at EL2, so make sure to sort them so this can be done efficiently.
> 
> Signed-off-by: Quentin Perret <[e-mail]>
> ---
>  arch/arm64/kvm/hyp/reserved_mem.c | 19 +++++++++++++++++++
>  1 file changed, 19 insertions(+)

Acked-by: Will Deacon <[e-mail]>

Will

Patch

diff --git a/arch/arm64/kvm/hyp/reserved_mem.c b/arch/arm64/kvm/hyp/reserved_mem.c
index fd42705a3c26..83ca23ac259b 100644
--- a/arch/arm64/kvm/hyp/reserved_mem.c
+++ b/arch/arm64/kvm/hyp/reserved_mem.c
@@ -6,6 +6,7 @@ 
 
 #include <linux/kvm_host.h>
 #include <linux/memblock.h>
+#include <linux/sort.h>
 
 #include <asm/kvm_host.h>
 
@@ -18,6 +19,23 @@  static unsigned int *hyp_memblock_nr_ptr = &kvm_nvhe_sym(hyp_memblock_nr);
 phys_addr_t hyp_mem_base;
 phys_addr_t hyp_mem_size;
 
+static int cmp_hyp_memblock(const void *p1, const void *p2)
+{
+	const struct memblock_region *r1 = p1;
+	const struct memblock_region *r2 = p2;
+
+	return r1->base < r2->base ? -1 : (r1->base > r2->base);
+}
+
+static void __init sort_memblock_regions(void)
+{
+	sort(hyp_memory,
+	     *hyp_memblock_nr_ptr,
+	     sizeof(struct memblock_region),
+	     cmp_hyp_memblock,
+	     NULL);
+}
+
 static int __init register_memblock_regions(void)
 {
 	struct memblock_region *reg;
@@ -29,6 +47,7 @@  static int __init register_memblock_regions(void)
 		hyp_memory[*hyp_memblock_nr_ptr] = *reg;
 		(*hyp_memblock_nr_ptr)++;
 	}
+	sort_memblock_regions();
 
 	return 0;
 }