[PATCH for-4.9 2/2] kbuild: simplify access to the kernel's version

[Jiaxun Yang <jiaxun.yang@xxxxxxxxxxx>]

From: Sasha Levin <sashal@xxxxxxxxxx>

commit 88a686728b3739d3598851e729c0e81f194e5c53 upstream.

Instead of storing the version in a single integer and having various
kernel (and userspace) code how it's constructed, export individual
(major, patchlevel, sublevel) components and simplify kernel code that
uses it.

This should also make it easier on userspace.

Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
Acked-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Masahiro Yamada <masahiroy@xxxxxxxxxx>
[jiaxun.yang@xxxxxxxxxxx: Stable backport, remove mlx5 part,
fix geth as well.]
Signed-off-by: Jiaxun Yang <jiaxun.yang@xxxxxxxxxxx>
---
 Makefile                      | 5 ++++-
 drivers/scsi/gdth.c           | 6 +++---
 drivers/usb/core/hcd.c        | 4 ++--
 include/linux/usb/composite.h | 4 ++--
 kernel/sys.c                  | 2 +-
 5 files changed, 12 insertions(+), 9 deletions(-)

diff --git a/Makefile b/Makefile
index c86dfa5b27bb..1b83b7011c7a 100644
--- a/Makefile
+++ b/Makefile
@@ -1148,7 +1148,10 @@ define filechk_version.h
 		expr $(VERSION) \* 65536 + 0$(PATCHLEVEL) \* 256 + $(SUBLEVEL)); \
 	fi;                                                              \
 	echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) +  \
-	((c) > 255 ? 255 : (c)))'
+	((c) > 255 ? 255 : (c)))';                                       \
+	echo \#define LINUX_VERSION_MAJOR $(VERSION);                    \
+	echo \#define LINUX_VERSION_PATCHLEVEL $(PATCHLEVEL);            \
+	echo \#define LINUX_VERSION_SUBLEVEL $(SUBLEVEL)
 endef
 
 $(version_h): $(srctree)/Makefile FORCE
diff --git a/drivers/scsi/gdth.c b/drivers/scsi/gdth.c
index 0a767740bf02..3cf78d28ad1d 100644
--- a/drivers/scsi/gdth.c
+++ b/drivers/scsi/gdth.c
@@ -4497,9 +4497,9 @@ static int gdth_ioctl(struct file *filep, unsigned int cmd, unsigned long arg)
       { 
         gdth_ioctl_osvers osv; 
 
-        osv.version = (u8)(LINUX_VERSION_CODE >> 16);
-        osv.subversion = (u8)(LINUX_VERSION_CODE >> 8);
-        osv.revision = (u16)(LINUX_VERSION_CODE & 0xff);
+        osv.version = LINUX_VERSION_MAJOR;
+        osv.subversion = LINUX_VERSION_PATCHLEVEL;
+        osv.revision = LINUX_VERSION_SUBLEVEL;
         if (copy_to_user(argp, &osv, sizeof(gdth_ioctl_osvers)))
                 return -EFAULT;
         break;
diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c
index 2246731d96b0..25825d6cab3c 100644
--- a/drivers/usb/core/hcd.c
+++ b/drivers/usb/core/hcd.c
@@ -125,8 +125,8 @@ static inline int is_root_hub(struct usb_device *udev)
  */
 
 /*-------------------------------------------------------------------------*/
-#define KERNEL_REL	bin2bcd(((LINUX_VERSION_CODE >> 16) & 0x0ff))
-#define KERNEL_VER	bin2bcd(((LINUX_VERSION_CODE >> 8) & 0x0ff))
+#define KERNEL_REL	bin2bcd(LINUX_VERSION_MAJOR)
+#define KERNEL_VER	bin2bcd(LINUX_VERSION_PATCHLEVEL)
 
 /* usb 3.1 root hub device descriptor */
 static const u8 usb31_rh_dev_descriptor[18] = {
diff --git a/include/linux/usb/composite.h b/include/linux/usb/composite.h
index 0ec7185e5ddf..a020f3cbc9f8 100644
--- a/include/linux/usb/composite.h
+++ b/include/linux/usb/composite.h
@@ -570,8 +570,8 @@ static inline u16 get_default_bcdDevice(void)
 {
 	u16 bcdDevice;
 
-	bcdDevice = bin2bcd((LINUX_VERSION_CODE >> 16 & 0xff)) << 8;
-	bcdDevice |= bin2bcd((LINUX_VERSION_CODE >> 8 & 0xff));
+	bcdDevice = bin2bcd(LINUX_VERSION_MAJOR) << 8;
+	bcdDevice |= bin2bcd(LINUX_VERSION_PATCHLEVEL);
 	return bcdDevice;
 }
 
diff --git a/kernel/sys.c b/kernel/sys.c
index 2e1def48ed73..1e4f88b12008 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -1132,7 +1132,7 @@ static int override_release(char __user *release, size_t len)
 				break;
 			rest++;
 		}
-		v = ((LINUX_VERSION_CODE >> 8) & 0xff) + 60;
+		v = LINUX_VERSION_PATCHLEVEL + 60;
 		copy = clamp_t(size_t, len, 1, sizeof(buf));
 		copy = scnprintf(buf, copy, "2.6.%u%s", v, rest);
 		ret = copy_to_user(release, buf, copy + 1);
-- 
2.35.1