[PATCH] random: vDSO: Redefine PAGE_SIZE and PAGE_MASK

Using PAGE_SIZE and PAGE_MASK in VDSO requires inclusion of
page.h and it creates several problems, see
commit 8b3843ae3634 ("vdso/datapage: Quick fix - use asm/page-def.h
for ARM64") and commit cffaefd15a8f ("vdso: Use CONFIG_PAGE_SHIFT in
vdso/datapage.h").

Redefine PAGE_SIZE and PAGE_MASK based on CONFIG_PAGE_SHIFT.

Signed-off-by: Christophe Leroy <redacted>
---
v3: Use local consts instead of _PAGE_SIZE and _PAGE_MASK macros that are already defined by some architectures.

v4: undefine and redefine PAGE_SIZE and PAGE_MASK
---
 lib/vdso/getrandom.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/lib/vdso/getrandom.c b/lib/vdso/getrandom.c
index f1643656d0b0..e5968ed141cb 100644
--- a/lib/vdso/getrandom.c
+++ b/lib/vdso/getrandom.c

@@ -14,6 +14,11 @@
 #include <asm/unaligned.h>
 #include <uapi/linux/mman.h>
 
+#undef PAGE_SIZE
+#undef PAGE_MASK
+#define PAGE_SIZE	(1UL << CONFIG_PAGE_SHIFT)
+#define PAGE_MASK	(~(PAGE_SIZE - 1))
+
 #define MEMCPY_AND_ZERO_SRC(type, dst, src, len) do {				\
 	while (len >= sizeof(type)) {						\
 		__put_unaligned_t(type, __get_unaligned_t(type, src), dst);	\

-- 
2.44.0