time: Introduce CONFIG_64BIT_TIME in architectures

deepa-hub · arndb · commit d4703ddafd1e · 2018-04-19T13:30:21.000+02:00
There are a total of 53 system calls (aside from ioctl) that pass a time_t
or derived data structure as an argument, and in order to extend time_t
to 64-bit, we have to replace them with new system calls and keep providing
backwards compatibility.

To avoid adding completely new and untested code for this purpose, we
introduce a new CONFIG_64BIT_TIME symbol. Every architecture that supports
new 64 bit time_t syscalls enables this config.

After this is done for all architectures, the CONFIG_64BIT_TIME symbol
will be deleted.

Signed-off-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Signed-off-by: Deepa Dinamani &lt;deepa.kernel@gmail.com&gt;
Signed-off-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
diff --git a/arch/Kconfig b/arch/Kconfig
@@ -870,6 +870,14 @@ config OLD_SIGACTION
 config COMPAT_OLD_SIGACTION
 	bool
 
+config 64BIT_TIME
+	def_bool ARCH_HAS_64BIT_TIME
+	help
+	  This should be selected by all architectures that need to support
+	  new system calls with a 64-bit time_t. 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
 
