arm: include asm-generic/memory_model.h from page.h rather than memory.h

Patch series "mm, arch: add generic implementation of pfn_valid() for
FLATMEM", v2.

Every architecture that supports FLATMEM memory model defines its own
version of pfn_valid() that essentially compares a pfn to max_mapnr.

Use mips/powerpc version implemented as static inline as a generic
implementation of pfn_valid() and drop its per-architecture definitions


This patch (of 4):

Makes it consistent with other architectures and allows for generic
definition of pfn_valid() in asm-generic/memory_model.h with clear
override in arch/arm/include/asm/page.h

Link: https://lkml.kernel.org/r/20230129124235.209895-1-rppt@kernel.org
Link: https://lkml.kernel.org/r/20230129124235.209895-2-rppt@kernel.org
Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brian Cain <bcain@quicinc.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: Guo Ren <guoren@kernel.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Huacai Chen <chenhuacai@loongson.cn>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Vineet Gupta <vgupta@kernel.org>
Cc: WANG Xuerui <kernel@xen0n.name>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

arch/arm/include/asm/memory.h

@@ -386,6 +386,4 @@ static inline unsigned long __virt_to_idmap(unsigned long x)
 
 #endif
 
-#include <asm-generic/memory_model.h>
-
 #endif

arch/arm/include/asm/page.h

@@ -158,6 +158,7 @@ typedef struct page *pgtable_t;
 
 #ifdef CONFIG_HAVE_ARCH_PFN_VALID
 extern int pfn_valid(unsigned long);
+#define pfn_valid pfn_valid
 #endif
 
 #include <asm/memory.h>
@@ -167,5 +168,6 @@ extern int pfn_valid(unsigned long);
 #define VM_DATA_DEFAULT_FLAGS	VM_DATA_FLAGS_TSK_EXEC
 
 #include <asm-generic/getorder.h>
+#include <asm-generic/memory_model.h>
 
 #endif