x86: MSR: add a struct representation of an MSR

Add a struct representing a 64bit MSR pair consisting of a low and high
register part and convert msr_info to use it. Also, rename msr-on-cpu.c
to msr.c.

Side note: Put the cpumask.h include in __KERNEL__ space thus fixing an
allmodconfig build failure in the headers_check target.

CC: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>

3 files changed, 25 insertions, 14 deletions

diff --git a/arch/x86/include/asm/msr.h b/arch/x86/include/asm/msr.h
index 638bf6241807..5e1213216e2b 100644
--- a/arch/x86/include/asm/msr.h
+++ b/arch/x86/include/asm/msr.h
@@ -12,6 +12,17 @@
 
 #include <asm/asm.h>
 #include <asm/errno.h>
+#include <asm/cpumask.h>
+
+struct msr {
+        union {
+                struct {
+                        u32 l;
+                        u32 h;
+                };
+                u64 q;
+        };
+};
 
 static inline unsigned long long native_read_tscp(unsigned int *aux)
 {
diff --git a/arch/x86/lib/Makefile b/arch/x86/lib/Makefile
index 55e11aa6d66c..f9d35632666b 100644
--- a/arch/x86/lib/Makefile
+++ b/arch/x86/lib/Makefile
@@ -2,7 +2,7 @@
 # Makefile for x86 specific library files.
 #
 
-obj-$(CONFIG_SMP) := msr-on-cpu.o
+obj-$(CONFIG_SMP) := msr.o
 
 lib-y := delay.o
 lib-y += thunk_$(BITS).o
diff --git a/arch/x86/lib/msr-on-cpu.c b/arch/x86/lib/msr.c
index 321cf720dbb6..cade714e57f9 100644
--- a/arch/x86/lib/msr-on-cpu.c
+++ b/arch/x86/lib/msr.c
@@ -5,7 +5,7 @@
 
 struct msr_info {
         u32 msr_no;
-        u32 l, h;
+        struct msr reg;
         int err;
 };
 
@@ -13,14 +13,14 @@ static void __rdmsr_on_cpu(void *info)
 {
         struct msr_info *rv = info;
 
-        rdmsr(rv->msr_no, rv->l, rv->h);
+        rdmsr(rv->msr_no, rv->reg.l, rv->reg.h);
 }
 
 static void __wrmsr_on_cpu(void *info)
 {
         struct msr_info *rv = info;
 
-        wrmsr(rv->msr_no, rv->l, rv->h);
+        wrmsr(rv->msr_no, rv->reg.l, rv->reg.h);
 }
 
 int rdmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h)
@@ -30,8 +30,8 @@ int rdmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h)
 
         rv.msr_no = msr_no;
         err = smp_call_function_single(cpu, __rdmsr_on_cpu, &rv, 1);
-        *l = rv.l;
-        *h = rv.h;
+        *l = rv.reg.l;
+        *h = rv.reg.h;
 
         return err;
 }
@@ -42,8 +42,8 @@ int wrmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h)
         struct msr_info rv;
 
         rv.msr_no = msr_no;
-        rv.l = l;
-        rv.h = h;
+        rv.reg.l = l;
+        rv.reg.h = h;
         err = smp_call_function_single(cpu, __wrmsr_on_cpu, &rv, 1);
 
         return err;
@@ -55,14 +55,14 @@ static void __rdmsr_safe_on_cpu(void *info)
 {
         struct msr_info *rv = info;
 
-        rv->err = rdmsr_safe(rv->msr_no, &rv->l, &rv->h);
+        rv->err = rdmsr_safe(rv->msr_no, &rv->reg.l, &rv->reg.h);
 }
 
 static void __wrmsr_safe_on_cpu(void *info)
 {
         struct msr_info *rv = info;
 
-        rv->err = wrmsr_safe(rv->msr_no, rv->l, rv->h);
+        rv->err = wrmsr_safe(rv->msr_no, rv->reg.l, rv->reg.h);
 }
 
 int rdmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h)
@@ -72,8 +72,8 @@ int rdmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h)
 
         rv.msr_no = msr_no;
         err = smp_call_function_single(cpu, __rdmsr_safe_on_cpu, &rv, 1);
-        *l = rv.l;
-        *h = rv.h;
+        *l = rv.reg.l;
+        *h = rv.reg.h;
 
         return err ? err : rv.err;
 }
@@ -84,8 +84,8 @@ int wrmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h)
         struct msr_info rv;
 
         rv.msr_no = msr_no;
-        rv.l = l;
-        rv.h = h;
+        rv.reg.l = l;
+        rv.reg.h = h;
         err = smp_call_function_single(cpu, __wrmsr_safe_on_cpu, &rv, 1);
 
         return err ? err : rv.err;