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authorBorislav Petkov <borislav.petkov@amd.com>2009-05-22 14:12:01 +0400
committerBorislav Petkov <borislav.petkov@amd.com>2009-06-10 14:18:42 +0400
commit6bc1096d7ab3621b3ffcf06616d1f4e0325d903d (patch)
tree286d1e4545fbd69c25fb4a5044d1d51122169a1d /arch/x86/lib/msr.c
parent07a2039b8eb0af4ff464efd3dfd95de5c02648c6 (diff)
downloadlinux-6bc1096d7ab3621b3ffcf06616d1f4e0325d903d.tar.xz
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>
Diffstat (limited to 'arch/x86/lib/msr.c')
-rw-r--r--arch/x86/lib/msr.c97
1 files changed, 97 insertions, 0 deletions
diff --git a/arch/x86/lib/msr.c b/arch/x86/lib/msr.c
new file mode 100644
index 000000000000..cade714e57f9
--- /dev/null
+++ b/arch/x86/lib/msr.c
@@ -0,0 +1,97 @@
+#include <linux/module.h>
+#include <linux/preempt.h>
+#include <linux/smp.h>
+#include <asm/msr.h>
+
+struct msr_info {
+ u32 msr_no;
+ struct msr reg;
+ int err;
+};
+
+static void __rdmsr_on_cpu(void *info)
+{
+ struct msr_info *rv = info;
+
+ 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->reg.l, rv->reg.h);
+}
+
+int rdmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h)
+{
+ int err;
+ struct msr_info rv;
+
+ rv.msr_no = msr_no;
+ err = smp_call_function_single(cpu, __rdmsr_on_cpu, &rv, 1);
+ *l = rv.reg.l;
+ *h = rv.reg.h;
+
+ return err;
+}
+
+int wrmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h)
+{
+ int err;
+ struct msr_info rv;
+
+ rv.msr_no = msr_no;
+ rv.reg.l = l;
+ rv.reg.h = h;
+ err = smp_call_function_single(cpu, __wrmsr_on_cpu, &rv, 1);
+
+ return err;
+}
+
+/* These "safe" variants are slower and should be used when the target MSR
+ may not actually exist. */
+static void __rdmsr_safe_on_cpu(void *info)
+{
+ struct msr_info *rv = info;
+
+ 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->reg.l, rv->reg.h);
+}
+
+int rdmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h)
+{
+ int err;
+ struct msr_info rv;
+
+ rv.msr_no = msr_no;
+ err = smp_call_function_single(cpu, __rdmsr_safe_on_cpu, &rv, 1);
+ *l = rv.reg.l;
+ *h = rv.reg.h;
+
+ return err ? err : rv.err;
+}
+
+int wrmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h)
+{
+ int err;
+ struct msr_info rv;
+
+ rv.msr_no = msr_no;
+ 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;
+}
+
+EXPORT_SYMBOL(rdmsr_on_cpu);
+EXPORT_SYMBOL(wrmsr_on_cpu);
+EXPORT_SYMBOL(rdmsr_safe_on_cpu);
+EXPORT_SYMBOL(wrmsr_safe_on_cpu);