[PATCH for-5.4,5.10] 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, fix geth as well.]
Signed-off-by: Jiaxun Yang <jiaxun.yang@xxxxxxxxxxx>
---
 Makefile                                       | 5 ++++-
 drivers/net/ethernet/mellanox/mlx5/core/main.c | 4 ++--
 drivers/scsi/gdth.c                            | 6 +++---
 drivers/usb/core/hcd.c                         | 4 ++--
 include/linux/usb/composite.h                  | 4 ++--
 kernel/sys.c                                   | 2 +-
 6 files changed, 14 insertions(+), 11 deletions(-)

diff --git a/Makefile b/Makefile
index 324939b64d7b..92dd066edd44 100644
--- a/Makefile
+++ b/Makefile
@@ -1183,7 +1183,10 @@ define filechk_version.h
 		expr $(VERSION) \* 65536 + $(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): PATCHLEVEL := $(if $(PATCHLEVEL), $(PATCHLEVEL), 0)
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/main.c b/drivers/net/ethernet/mellanox/mlx5/core/main.c
index f2657cd3ffa4..d57d0bc8d933 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/main.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/main.c
@@ -230,8 +230,8 @@ static void mlx5_set_driver_version(struct mlx5_core_dev *dev)
 	remaining_size = max_t(int, 0, driver_ver_sz - strlen(string));
 
 	snprintf(string + strlen(string), remaining_size, "%u.%u.%u",
-		 (u8)((LINUX_VERSION_CODE >> 16) & 0xff), (u8)((LINUX_VERSION_CODE >> 8) & 0xff),
-		 (u16)(LINUX_VERSION_CODE & 0xffff));
+		LINUX_VERSION_MAJOR, LINUX_VERSION_PATCHLEVEL,
+		LINUX_VERSION_SUBLEVEL);
 
 	/*Send the command*/
 	MLX5_SET(set_driver_version_in, in, opcode,
diff --git a/drivers/scsi/gdth.c b/drivers/scsi/gdth.c
index fe03410268e6..3ff0326f22fd 100644
--- a/drivers/scsi/gdth.c
+++ b/drivers/scsi/gdth.c
@@ -3907,9 +3907,9 @@ 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 39203f2ce6a1..323f210090bf 100644
--- a/drivers/usb/core/hcd.c
+++ b/drivers/usb/core/hcd.c
@@ -110,8 +110,8 @@ DECLARE_WAIT_QUEUE_HEAD(usb_kill_urb_queue);
  */
 
 /*-------------------------------------------------------------------------*/
-#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 2040696d75b6..764f58b74f26 100644
--- a/include/linux/usb/composite.h
+++ b/include/linux/usb/composite.h
@@ -573,8 +573,8 @@ 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 b075fe84eb5a..0278461760b0 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -1228,7 +1228,7 @@ 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