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>

diff --git a/arch/arm64/kvm/hyp/include/nvhe/gfp.h b/arch/arm64/kvm/hyp/include/nvhe/gfp.h
index 97c527ef53c2adeab264d9495ba380dfabcaa025..3766333bace966164d7dfd88b70a86284252e9bc 100644 (file)
--- 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 0964c461da9260c65e9a7f23fdfe833721df70be..8f2b42bcc8e115f1071e192689dcf3845c14b1f8 100644 (file)
--- 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 e691290d3765d38d9fb49d6f7abf949aae412c6a..a1eb27a1a74774a63e653ad6219edac28c1ea249 100644 (file)
--- 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 @@ insert:
 
 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);