[PATCH] vdso/datapage: Quick fix - use asm/page-def.h for ARM64

[Anna-Maria Behnsen]

The vdso rework for the generic union vdso_data_store broke compat VDSO on
arm64:

In file included from arch/arm64/include/asm/lse.h:5,
		 from arch/arm64/include/asm/cmpxchg.h:14,
		 from arch/arm64/include/asm/atomic.h:16,
		 from include/linux/atomic.h:7,
		 from include/asm-generic/bitops/atomic.h:5,
		 from arch/arm64/include/asm/bitops.h:25,
		 from include/linux/bitops.h:68,
		 from arch/arm64/include/asm/memory.h:209,
		 from arch/arm64/include/asm/page.h:46,
		 from include/vdso/datapage.h:22,
		 from lib/vdso/gettimeofday.c:5,
		 from <command-line>:
arch/arm64/include/asm/atomic_ll_sc.h:298:9: error: unknown type name 'u128'
  298 |         u128 full;
      |         ^~~~
arch/arm64/include/asm/atomic_ll_sc.h:305:24: error: unknown type name 'u128'
  305 | static __always_inline u128
	 \
      |

The reason is the include of asm/page.h which in turn includes headers
which are outside the scope of compat VDSO. The only reason for the
asm/page.h include is the required definition of PAGE_SIZE. But as arm64
defines PAGE_SIZE in asm/page-def.h without extra header includes, this
could be used instead.

Caution: this is a quick fix only! The final fix is an upcoming cleanup of
Arnd which consolidates PAGE_SIZE definition. After the cleanup, the
include of asm/page.h to access PAGE_SIZE is no longer required.

Reported-by: Linux Kernel Functional Testing <lkft@xxxxxxxxxx>
Fixes: a0d2fcd62ac2 ("vdso/ARM: Make union vdso_data_store available for all architectures")
Link: https://lore.kernel.org/lkml/CA+G9fYtrXXm_KO9fNPz3XaRxHV7UD_yQp-TEuPQrNRHU+_0W_Q@xxxxxxxxxxxxxx/
Signed-off-by: Anna-Maria Behnsen <anna-maria@xxxxxxxxxxxxx>
---

Patch applies on tip/timers/core and was tested with clang-14

---
 include/vdso/datapage.h | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/include/vdso/datapage.h b/include/vdso/datapage.h
index 7ba44379a095..5d5c0b8efff2 100644
--- a/include/vdso/datapage.h
+++ b/include/vdso/datapage.h
@@ -19,7 +19,11 @@
 #include <vdso/time32.h>
 #include <vdso/time64.h>
 
+#ifdef CONFIG_ARM64
+#include <asm/page-def.h>
+#else
 #include <asm/page.h>
+#endif
 
 #ifdef CONFIG_ARCH_HAS_VDSO_DATA
 #include <asm/vdso/data.h>
-- 
2.39.2