nfp: add nfp_cpp_area_size() accessor

Allow users outside of core reading area sizes.  This was not needed
previously because whatever entity created the area would usually know
what size it asked for.  The nfp_rtsym_map() helper, however, will
allocate the area based on the size of an RT-symbol with given name.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

drivers/net/ethernet/netronome/nfp/nfpcore/nfp_cpp.h

@@ -242,6 +242,7 @@ int nfp_cpp_area_read(struct nfp_cpp_area *area, unsigned long offset,
 		      void *buffer, size_t length);
 int nfp_cpp_area_write(struct nfp_cpp_area *area, unsigned long offset,
 		       const void *buffer, size_t length);
+size_t nfp_cpp_area_size(struct nfp_cpp_area *area);
 const char *nfp_cpp_area_name(struct nfp_cpp_area *cpp_area);
 void *nfp_cpp_area_priv(struct nfp_cpp_area *cpp_area);
 struct nfp_cpp *nfp_cpp_area_cpp(struct nfp_cpp_area *cpp_area);

drivers/net/ethernet/netronome/nfp/nfpcore/nfp_cppcore.c

@@ -567,6 +567,17 @@ int nfp_cpp_area_write(struct nfp_cpp_area *area,
 	return area->cpp->op->area_write(area, kernel_vaddr, offset, length);
 }
 
+/**
+ * nfp_cpp_area_size() - return size of a CPP area
+ * @cpp_area:	CPP area handle
+ *
+ * Return: Size of the area
+ */
+size_t nfp_cpp_area_size(struct nfp_cpp_area *cpp_area)
+{
+	return cpp_area->size;
+}
+
 /**
  * nfp_cpp_area_name() - return name of a CPP area
  * @cpp_area:	CPP area handle