[PATCH] plat/arm64: Fix extregs allocation on Arm

[Jia He <justin.he@xxxxxxx>]

Implement the extregs (currently only fpsimd registers) allocation
related helpers. Otherwise, Unikraft can be built on Arm kvm plat
due to the missing of several helpers.

Signed-off-by: Jia He <justin.he@xxxxxxx>
---
 plat/common/include/arm/arm64/cpu.h | 31 ++++++++++-------------------
 1 file changed, 11 insertions(+), 20 deletions(-)

diff --git a/plat/common/include/arm/arm64/cpu.h 
b/plat/common/include/arm/arm64/cpu.h
index a3fb730..804a34b 100644
--- a/plat/common/include/arm/arm64/cpu.h
+++ b/plat/common/include/arm/arm64/cpu.h
@@ -175,24 +175,19 @@ static inline void restore_extregs(struct sw_ctx *ctx)
        isb();
 }
 
-static inline struct sw_ctx *arch_alloc_sw_ctx(struct uk_alloc *allocator)
+static inline void arch_init_extregs(struct sw_ctx *ctx __unused)
 {
-       struct sw_ctx *ctx;
-
-       ctx = (struct sw_ctx *)uk_malloc(allocator,
-                       sizeof(struct sw_ctx) + sizeof(struct fpsimd_state));
        if (ctx)
-               ctx->extregs = (uintptr_t)((void *)ctx + sizeof(struct sw_ctx));
+               ctx->extregs = (uintptr_t)ctx->_extregs;
 
        uk_pr_debug("Allocating %lu + %lu bytes for sw ctx at %p, extregs at 
%p\n",
                        sizeof(struct sw_ctx), sizeof(struct fpsimd_state),
                        ctx, (void *)ctx->extregs);
-
-       return ctx;
 }
 
-static inline void arch_init_extregs(struct sw_ctx *ctx __unused)
+static inline __sz arch_extregs_size(void)
 {
+       return sizeof(struct fpsimd_state);
 }
 
 #else /* !CONFIG_FPSIMD */
@@ -204,21 +199,17 @@ static inline void restore_extregs(struct sw_ctx *ctx 
__unused)
 {
 }
 
-static inline struct sw_ctx *arch_alloc_sw_ctx(struct uk_alloc *allocator)
+static inline void arch_init_extregs(struct sw_ctx *ctx)
 {
-       struct sw_ctx *ctx;
-
-       ctx = (struct sw_ctx *)uk_malloc(allocator, sizeof(struct sw_ctx));
-       uk_pr_debug("Allocating %lu bytes for sw ctx at %p\n",
-               sizeof(struct sw_ctx), ctx);
-
-       return ctx;
+       if (ctx)
+               ctx->extregs = (uintptr_t)ctx->_extregs;
 }
 
-static inline void arch_init_extregs(struct sw_ctx *ctx)
+static inline __sz arch_extregs_size(void)
 {
-       ctx->extregs = (uintptr_t)ctx + sizeof(struct sw_ctx);
+       return 0;
 }
-
 #endif /* CONFIG_FPSIMD */
+
+
 #endif /* __PLAT_COMMON_ARM64_CPU_H__ */
-- 
2.17.1