tools/testing/scatterlist: Rejuvenate bit-rotten test

A couple small tweaks are needed to make the test build and run
on current kernels.

Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Tvrtko Ursulin <[e-mail]>
Cc: Maor Gottlieb <[e-mail]>
Signed-off-by: Leon Romanovsky <[e-mail]>
Signed-off-by: Jason Gunthorpe <[e-mail]>

tools/testing/scatterlist/Makefile

···
 main: $(OFILES)
 
 clean:
-	$(RM) $(TARGETS) $(OFILES) scatterlist.c linux/scatterlist.h linux/highmem.h linux/kmemleak.h asm/io.h
+	$(RM) $(TARGETS) $(OFILES) scatterlist.c linux/scatterlist.h linux/highmem.h linux/kmemleak.h linux/slab.h asm/io.h
 	@rmdir asm
 
 scatterlist.c: ../../../lib/scatterlist.c
···
 	@touch asm/io.h
 	@touch linux/highmem.h
 	@touch linux/kmemleak.h
+	@touch linux/slab.h
 	@cp $< linux/scatterlist.h

tools/testing/scatterlist/linux/mm.h

···
 	return malloc(size);
 }
 
+static inline void *
+kmalloc_array(unsigned int n, unsigned int size, unsigned int flags)
+{
+	return malloc(n * size);
+}
+
 #define kfree(x) free(x)
 
 #define kmemleak_alloc(a, b, c, d)
···
 
 #define PageSlab(p) (0)
 #define flush_kernel_dcache_page(p)
+
+#define MAX_ERRNO	4095
+
+#define IS_ERR_VALUE(x) unlikely((unsigned long)(void *)(x) >= (unsigned long)-MAX_ERRNO)
+
+static inline void * __must_check ERR_PTR(long error)
+{
+	return (void *) error;
+}
+
+static inline long __must_check PTR_ERR(__force const void *ptr)
+{
+	return (long) ptr;
+}
+
+static inline bool __must_check IS_ERR(__force const void *ptr)
+{
+	return IS_ERR_VALUE((unsigned long)ptr);
+}
+
+static inline int __must_check PTR_ERR_OR_ZERO(__force const void *ptr)
+{
+	if (IS_ERR(ptr))
+		return PTR_ERR(ptr);
+	else
+		return 0;
+}
+
+#define IS_ENABLED(x) (0)
 
 #endif