time: Introduce CONFIG_COMPAT_32BIT_TIME

Compat functions are now used to support 32 bit time_t in
compat mode on 64 bit architectures and in native mode on
32 bit architectures.

Introduce COMPAT_32BIT_TIME to conditionally compile these
functions.

Note that turning off 32 bit time_t support requires more
changes on architecture side. For instance, architecure
syscall tables need to be updated to drop support for 32 bit
time_t syscalls.

Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

diff --git a/arch/Kconfig b/arch/Kconfig
index 16e6acf..4377b0c 100644 (file)
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -878,6 +878,13 @@ config 64BIT_TIME
          architectures, and 64-bit architectures as part of compat syscall
          handling.
 
+config COMPAT_32BIT_TIME
+       def_bool (!64BIT && 64BIT_TIME) || COMPAT
+       help
+         This enables 32 bit time_t support in addition to 64 bit time_t support.
+         This is relevant on all 32-bit architectures, and 64-bit architectures
+         as part of compat syscall handling.
+
 config ARCH_NO_COHERENT_DMA_MMAP
        bool