kselftest/arm64: move get_header()

Put this function in the header so that it can be used by other tests, without
needing to link to testcases.c.

This will be used by selftest/mm/protection_keys.c
Signed-off-by: Joey Gouly <joey.gouly@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Reviewed-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20240822151113.1479789-25-joey.gouly@arm.comSigned-off-by: Will Deacon <will@kernel.org>

tools/testing/selftests/arm64/signal/testcases/testcases.c

@@ -6,29 +6,6 @@
 
 #include "testcases.h"
 
-struct _aarch64_ctx *get_header(struct _aarch64_ctx *head, uint32_t magic,
-				size_t resv_sz, size_t *offset)
-{
-	size_t offs = 0;
-	struct _aarch64_ctx *found = NULL;
-
-	if (!head || resv_sz < HDR_SZ)
-		return found;
-
-	while (offs <= resv_sz - HDR_SZ &&
-	       head->magic != magic && head->magic) {
-		offs += head->size;
-		head = GET_RESV_NEXT_HEAD(head);
-	}
-	if (head->magic == magic) {
-		found = head;
-		if (offset)
-			*offset = offs;
-	}
-
-	return found;
-}
-
 bool validate_extra_context(struct extra_context *extra, char **err,
 			    void **extra_data, size_t *extra_size)
 {

tools/testing/selftests/arm64/signal/testcases/testcases.h

@@ -88,8 +88,29 @@ struct fake_sigframe {
 
 bool validate_reserved(ucontext_t *uc, size_t resv_sz, char **err);
 
-struct _aarch64_ctx *get_header(struct _aarch64_ctx *head, uint32_t magic,
-				size_t resv_sz, size_t *offset);
+static inline struct _aarch64_ctx *get_header(struct _aarch64_ctx *head, uint32_t magic,
+				size_t resv_sz, size_t *offset)
+{
+	size_t offs = 0;
+	struct _aarch64_ctx *found = NULL;
+
+	if (!head || resv_sz < HDR_SZ)
+		return found;
+
+	while (offs <= resv_sz - HDR_SZ &&
+	       head->magic != magic && head->magic) {
+		offs += head->size;
+		head = GET_RESV_NEXT_HEAD(head);
+	}
+	if (head->magic == magic) {
+		found = head;
+		if (offset)
+			*offset = offs;
+	}
+
+	return found;
+}
+
 
 static inline struct _aarch64_ctx *get_terminator(struct _aarch64_ctx *head,
 						  size_t resv_sz,