1 files changed, 68 insertions, 0 deletions
diff --git a/arch/arm64/kvm/hyp/include/nvhe/gfp.h b/arch/arm64/kvm/hyp/include/nvhe/gfp.h
new file mode 100644
index 000000000000..18a4494337bd
--- /dev/null
+++ b/arch/arm64/kvm/hyp/include/nvhe/gfp.h
@@ -0,0 +1,68 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+#ifndef __KVM_HYP_GFP_H
+#define __KVM_HYP_GFP_H
+
+#include <linux/list.h>
+
+#include <nvhe/memory.h>
+#include <nvhe/spinlock.h>
+
+#define HYP_NO_ORDER	UINT_MAX
+
+struct hyp_pool {
+	/*
+	 * Spinlock protecting concurrent changes to the memory pool as well as
+	 * the struct hyp_page of the pool's pages until we have a proper atomic
+	 * API at EL2.
+	 */
+	hyp_spinlock_t lock;
+	struct list_head free_area[MAX_ORDER];
+	phys_addr_t range_start;
+	phys_addr_t range_end;
+	unsigned int max_order;
+};
+
+static inline void hyp_page_ref_inc(struct hyp_page *p)
+{
+	struct hyp_pool *pool = hyp_page_to_pool(p);
+
+	hyp_spin_lock(&pool->lock);
+	p->refcount++;
+	hyp_spin_unlock(&pool->lock);
+}
+
+static inline int hyp_page_ref_dec_and_test(struct hyp_page *p)
+{
+	struct hyp_pool *pool = hyp_page_to_pool(p);
+	int ret;
+
+	hyp_spin_lock(&pool->lock);
+	p->refcount--;
+	ret = (p->refcount == 0);
+	hyp_spin_unlock(&pool->lock);
+
+	return ret;
+}
+
+static inline void hyp_set_page_refcounted(struct hyp_page *p)
+{
+	struct hyp_pool *pool = hyp_page_to_pool(p);
+
+	hyp_spin_lock(&pool->lock);
+	if (p->refcount) {
+		hyp_spin_unlock(&pool->lock);
+		BUG();
+	}
+	p->refcount = 1;
+	hyp_spin_unlock(&pool->lock);
+}
+
+/* Allocation */
+void *hyp_alloc_pages(struct hyp_pool *pool, unsigned int order);
+void hyp_get_page(void *addr);
+void hyp_put_page(void *addr);
+
+/* Used pages cannot be freed */
+int hyp_pool_init(struct hyp_pool *pool, u64 pfn, unsigned int nr_pages,
+		  unsigned int reserved_pages);
+#endif /* __KVM_HYP_GFP_H */