[PATCH v4] hyperv: simplify and rename generate_guest_id

[Li kunyu]

The generate_guest_id function is more suitable for use after the
following modifications.
1. Modify the type of the guest_id variable to u64, which is compatible
with the caller.
2. Remove all parameters from the function, and write the parameter
(LINUX_VERSION_CODE) passed in by the actual call into the function
implementation.
3. Rename the function to make it clearly a Hyper-V related function,
and modify it to hv_generate_guest_id.

Signed-off-by: Li kunyu <kunyu at nfschina.com>

--------
 v2: Fix generate_guest_id to hv_generate_guest_id.
 v3: Fix [PATCH v2] asm-generic: Remove the ... to [PATCH v3] hyperv: simp
     lify ... and remove extra spaces 
 v4: Remove #include <linux/version.h> in the calling file, and add #inclu
     de <linux/version.h> in the function implementation file
---
 arch/arm64/hyperv/mshyperv.c   |  3 +--
 arch/x86/hyperv/hv_init.c      |  3 +--
 include/asm-generic/mshyperv.h | 12 +++++-------
 3 files changed, 7 insertions(+), 11 deletions(-)

diff --git a/arch/arm64/hyperv/mshyperv.c b/arch/arm64/hyperv/mshyperv.c
index bbbe351e9045..637186f4df1f 100644
--- a/arch/arm64/hyperv/mshyperv.c
+++ b/arch/arm64/hyperv/mshyperv.c
@@ -13,7 +13,6 @@
 #include <linux/acpi.h>
 #include <linux/export.h>
 #include <linux/errno.h>
-#include <linux/version.h>
 #include <linux/cpuhotplug.h>
 #include <asm/mshyperv.h>
 
@@ -38,7 +37,7 @@ static int __init hyperv_init(void)
 		return 0;
 
 	/* Setup the guest ID */
-	guest_id = generate_guest_id(0, LINUX_VERSION_CODE, 0);
+	guest_id = hv_generate_guest_id();
 	hv_set_vpreg(HV_REGISTER_GUEST_OSID, guest_id);
 
 	/* Get the features and hints from Hyper-V */
diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c
index 3de6d8b53367..04d32cd3e838 100644
--- a/arch/x86/hyperv/hv_init.c
+++ b/arch/x86/hyperv/hv_init.c
@@ -19,7 +19,6 @@
 #include <asm/mshyperv.h>
 #include <asm/idtentry.h>
 #include <linux/kexec.h>
-#include <linux/version.h>
 #include <linux/vmalloc.h>
 #include <linux/mm.h>
 #include <linux/hyperv.h>
@@ -426,7 +425,7 @@ void __init hyperv_init(void)
 	 * 1. Register the guest ID
 	 * 2. Enable the hypercall and register the hypercall page
 	 */
-	guest_id = generate_guest_id(0, LINUX_VERSION_CODE, 0);
+	guest_id = hv_generate_guest_id();
 	wrmsrl(HV_X64_MSR_GUEST_OS_ID, guest_id);
 
 	/* Hyper-V requires to write guest os id via ghcb in SNP IVM. */
diff --git a/include/asm-generic/mshyperv.h b/include/asm-generic/mshyperv.h
index c05d2ce9b6cd..9155575b7e34 100644
--- a/include/asm-generic/mshyperv.h
+++ b/include/asm-generic/mshyperv.h
@@ -25,6 +25,7 @@
 #include <linux/nmi.h>
 #include <asm/ptrace.h>
 #include <asm/hyperv-tlfs.h>
+#include <linux/version.h>
 
 struct ms_hyperv_info {
 	u32 features;
@@ -105,15 +106,12 @@ static inline u64 hv_do_rep_hypercall(u16 code, u16 rep_count, u16 varhead_size,
 }
 
 /* Generate the guest OS identifier as described in the Hyper-V TLFS */
-static inline  __u64 generate_guest_id(__u64 d_info1, __u64 kernel_version,
-				       __u64 d_info2)
+static inline u64 hv_generate_guest_id(void)
 {
-	__u64 guest_id = 0;
+	u64 guest_id;
 
-	guest_id = (((__u64)HV_LINUX_VENDOR_ID) << 48);
-	guest_id |= (d_info1 << 48);
-	guest_id |= (kernel_version << 16);
-	guest_id |= d_info2;
+	guest_id = (((u64)HV_LINUX_VENDOR_ID) << 48);
+	guest_id |= (((u64)LINUX_VERSION_CODE) << 16);
 
 	return guest_id;
 }
-- 
2.18.2