From b35875d466ad3cb08866eac067cca0581d4293d7 Mon Sep 17 00:00:00 2001
From: Quentin Perret <qperret@google.com>
Date: Wed, 18 Dec 2024 19:40:44 +0000
Subject: [PATCH] KVM: arm64: Make hyp_page::order a u8
We don't need 16 bits to store the hyp page order, and we'll need some
bits to store page ownership data soon, so let's reduce the order
member.
Tested-by: Fuad Tabba <tabba@google.com>
Reviewed-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Quentin Perret <qperret@google.com>
Link: https://lore.kernel.org/r/20241218194059.3670226-4-qperret@google.com
Signed-off-by: Marc Zyngier <maz@kernel.org>
---
arch/arm64/kvm/hyp/include/nvhe/gfp.h | 6 +++---
arch/arm64/kvm/hyp/include/nvhe/memory.h | 5 +++--
arch/arm64/kvm/hyp/nvhe/page_alloc.c | 14 +++++++-------
3 files changed, 13 insertions(+), 12 deletions(-)
diff --git a/arch/arm64/kvm/hyp/include/nvhe/gfp.h b/arch/arm64/kvm/hyp/include/nvhe/gfp.h
index 97c527ef53c2a..3766333bace96 100644
--- a/arch/arm64/kvm/hyp/include/nvhe/gfp.h
+++ b/arch/arm64/kvm/hyp/include/nvhe/gfp.h
@@ -7,7 +7,7 @@
#include <nvhe/memory.h>
#include <nvhe/spinlock.h>
-#define HYP_NO_ORDER USHRT_MAX
+#define HYP_NO_ORDER ((u8)(~0))
struct hyp_pool {
/*
@@ -19,11 +19,11 @@ struct hyp_pool {
struct list_head free_area[NR_PAGE_ORDERS];
phys_addr_t range_start;
phys_addr_t range_end;
- unsigned short max_order;
+ u8 max_order;
};
/* Allocation */
-void *hyp_alloc_pages(struct hyp_pool *pool, unsigned short order);
+void *hyp_alloc_pages(struct hyp_pool *pool, u8 order);
void hyp_split_page(struct hyp_page *page);
void hyp_get_page(struct hyp_pool *pool, void *addr);
void hyp_put_page(struct hyp_pool *pool, void *addr);
diff --git a/arch/arm64/kvm/hyp/include/nvhe/memory.h b/arch/arm64/kvm/hyp/include/nvhe/memory.h
index 0964c461da926..8f2b42bcc8e11 100644
--- a/arch/arm64/kvm/hyp/include/nvhe/memory.h
+++ b/arch/arm64/kvm/hyp/include/nvhe/memory.h
@@ -41,8 +41,9 @@ static inline enum pkvm_page_state pkvm_getstate(enum kvm_pgtable_prot prot)
}
struct hyp_page {
- unsigned short refcount;
- unsigned short order;
+ u16 refcount;
+ u8 order;
+ u8 reserved;
};
extern u64 __hyp_vmemmap;
diff --git a/arch/arm64/kvm/hyp/nvhe/page_alloc.c b/arch/arm64/kvm/hyp/nvhe/page_alloc.c
index e691290d3765d..a1eb27a1a7477 100644
--- a/arch/arm64/kvm/hyp/nvhe/page_alloc.c
+++ b/arch/arm64/kvm/hyp/nvhe/page_alloc.c
@@ -32,7 +32,7 @@ u64 __hyp_vmemmap;
*/
static struct hyp_page *__find_buddy_nocheck(struct hyp_pool *pool,
struct hyp_page *p,
- unsigned short order)
+ u8 order)
{
phys_addr_t addr = hyp_page_to_phys(p);
@@ -51,7 +51,7 @@ static struct hyp_page *__find_buddy_nocheck(struct hyp_pool *pool,
/* Find a buddy page currently available for allocation */
static struct hyp_page *__find_buddy_avail(struct hyp_pool *pool,
struct hyp_page *p,
- unsigned short order)
+ u8 order)
{
struct hyp_page *buddy = __find_buddy_nocheck(pool, p, order);
@@ -94,7 +94,7 @@ static void __hyp_attach_page(struct hyp_pool *pool,
struct hyp_page *p)
{
phys_addr_t phys = hyp_page_to_phys(p);
- unsigned short order = p->order;
+ u8 order = p->order;
struct hyp_page *buddy;
memset(hyp_page_to_virt(p), 0, PAGE_SIZE << p->order);
@@ -129,7 +129,7 @@ static void __hyp_attach_page(struct hyp_pool *pool,
static struct hyp_page *__hyp_extract_page(struct hyp_pool *pool,
struct hyp_page *p,
- unsigned short order)
+ u8 order)
{
struct hyp_page *buddy;
@@ -183,7 +183,7 @@ void hyp_get_page(struct hyp_pool *pool, void *addr)
void hyp_split_page(struct hyp_page *p)
{
- unsigned short order = p->order;
+ u8 order = p->order;
unsigned int i;
p->order = 0;
@@ -195,10 +195,10 @@ void hyp_split_page(struct hyp_page *p)
}
}
-void *hyp_alloc_pages(struct hyp_pool *pool, unsigned short order)
+void *hyp_alloc_pages(struct hyp_pool *pool, u8 order)
{
- unsigned short i = order;
struct hyp_page *p;
+ u8 i = order;
hyp_spin_lock(&pool->lock);