From 6bc1096d7ab3621b3ffcf06616d1f4e0325d903d Mon Sep 17 00:00:00 2001 From: Borislav Petkov Date: Fri, 22 May 2009 12:12:01 +0200 Subject: 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 Signed-off-by: Borislav Petkov --- arch/x86/lib/msr.c | 97 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 97 insertions(+) create mode 100644 arch/x86/lib/msr.c (limited to 'arch/x86/lib/msr.c') 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 +#include +#include +#include + +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); -- cgit v1.2.3