385 lines
11 KiB
C
385 lines
11 KiB
C
|
/* SPDX-License-Identifier: GPL-2.0 */
|
||
|
#ifndef _ASM_X86_MSR_H
|
||
|
#define _ASM_X86_MSR_H
|
||
|
|
||
|
#include "msr-index.h"
|
||
|
|
||
|
#ifndef __ASSEMBLY__
|
||
|
|
||
|
#include <asm/asm.h>
|
||
|
#include <asm/errno.h>
|
||
|
#include <asm/cpumask.h>
|
||
|
#include <uapi/asm/msr.h>
|
||
|
#include <asm/shared/msr.h>
|
||
|
|
||
|
struct msr_info {
|
||
|
u32 msr_no;
|
||
|
struct msr reg;
|
||
|
struct msr *msrs;
|
||
|
int err;
|
||
|
};
|
||
|
|
||
|
struct msr_regs_info {
|
||
|
u32 *regs;
|
||
|
int err;
|
||
|
};
|
||
|
|
||
|
struct saved_msr {
|
||
|
bool valid;
|
||
|
struct msr_info info;
|
||
|
};
|
||
|
|
||
|
struct saved_msrs {
|
||
|
unsigned int num;
|
||
|
struct saved_msr *array;
|
||
|
};
|
||
|
|
||
|
/*
|
||
|
* both i386 and x86_64 returns 64-bit value in edx:eax, but gcc's "A"
|
||
|
* constraint has different meanings. For i386, "A" means exactly
|
||
|
* edx:eax, while for x86_64 it doesn't mean rdx:rax or edx:eax. Instead,
|
||
|
* it means rax *or* rdx.
|
||
|
*/
|
||
|
#ifdef CONFIG_X86_64
|
||
|
/* Using 64-bit values saves one instruction clearing the high half of low */
|
||
|
#define DECLARE_ARGS(val, low, high) unsigned long low, high
|
||
|
#define EAX_EDX_VAL(val, low, high) ((low) | (high) << 32)
|
||
|
#define EAX_EDX_RET(val, low, high) "=a" (low), "=d" (high)
|
||
|
#else
|
||
|
#define DECLARE_ARGS(val, low, high) unsigned long long val
|
||
|
#define EAX_EDX_VAL(val, low, high) (val)
|
||
|
#define EAX_EDX_RET(val, low, high) "=A" (val)
|
||
|
#endif
|
||
|
|
||
|
/*
|
||
|
* Be very careful with includes. This header is prone to include loops.
|
||
|
*/
|
||
|
#include <asm/atomic.h>
|
||
|
#include <linux/tracepoint-defs.h>
|
||
|
|
||
|
#ifdef CONFIG_TRACEPOINTS
|
||
|
DECLARE_TRACEPOINT(read_msr);
|
||
|
DECLARE_TRACEPOINT(write_msr);
|
||
|
DECLARE_TRACEPOINT(rdpmc);
|
||
|
extern void do_trace_write_msr(unsigned int msr, u64 val, int failed);
|
||
|
extern void do_trace_read_msr(unsigned int msr, u64 val, int failed);
|
||
|
extern void do_trace_rdpmc(unsigned int msr, u64 val, int failed);
|
||
|
#else
|
||
|
static inline void do_trace_write_msr(unsigned int msr, u64 val, int failed) {}
|
||
|
static inline void do_trace_read_msr(unsigned int msr, u64 val, int failed) {}
|
||
|
static inline void do_trace_rdpmc(unsigned int msr, u64 val, int failed) {}
|
||
|
#endif
|
||
|
|
||
|
/*
|
||
|
* __rdmsr() and __wrmsr() are the two primitives which are the bare minimum MSR
|
||
|
* accessors and should not have any tracing or other functionality piggybacking
|
||
|
* on them - those are *purely* for accessing MSRs and nothing more. So don't even
|
||
|
* think of extending them - you will be slapped with a stinking trout or a frozen
|
||
|
* shark will reach you, wherever you are! You've been warned.
|
||
|
*/
|
||
|
static __always_inline unsigned long long __rdmsr(unsigned int msr)
|
||
|
{
|
||
|
DECLARE_ARGS(val, low, high);
|
||
|
|
||
|
asm volatile("1: rdmsr\n"
|
||
|
"2:\n"
|
||
|
_ASM_EXTABLE_TYPE(1b, 2b, EX_TYPE_RDMSR)
|
||
|
: EAX_EDX_RET(val, low, high) : "c" (msr));
|
||
|
|
||
|
return EAX_EDX_VAL(val, low, high);
|
||
|
}
|
||
|
|
||
|
static __always_inline void __wrmsr(unsigned int msr, u32 low, u32 high)
|
||
|
{
|
||
|
asm volatile("1: wrmsr\n"
|
||
|
"2:\n"
|
||
|
_ASM_EXTABLE_TYPE(1b, 2b, EX_TYPE_WRMSR)
|
||
|
: : "c" (msr), "a"(low), "d" (high) : "memory");
|
||
|
}
|
||
|
|
||
|
#define native_rdmsr(msr, val1, val2) \
|
||
|
do { \
|
||
|
u64 __val = __rdmsr((msr)); \
|
||
|
(void)((val1) = (u32)__val); \
|
||
|
(void)((val2) = (u32)(__val >> 32)); \
|
||
|
} while (0)
|
||
|
|
||
|
#define native_wrmsr(msr, low, high) \
|
||
|
__wrmsr(msr, low, high)
|
||
|
|
||
|
#define native_wrmsrl(msr, val) \
|
||
|
__wrmsr((msr), (u32)((u64)(val)), \
|
||
|
(u32)((u64)(val) >> 32))
|
||
|
|
||
|
static inline unsigned long long native_read_msr(unsigned int msr)
|
||
|
{
|
||
|
unsigned long long val;
|
||
|
|
||
|
val = __rdmsr(msr);
|
||
|
|
||
|
if (tracepoint_enabled(read_msr))
|
||
|
do_trace_read_msr(msr, val, 0);
|
||
|
|
||
|
return val;
|
||
|
}
|
||
|
|
||
|
static inline unsigned long long native_read_msr_safe(unsigned int msr,
|
||
|
int *err)
|
||
|
{
|
||
|
DECLARE_ARGS(val, low, high);
|
||
|
|
||
|
asm volatile("1: rdmsr ; xor %[err],%[err]\n"
|
||
|
"2:\n\t"
|
||
|
_ASM_EXTABLE_TYPE_REG(1b, 2b, EX_TYPE_RDMSR_SAFE, %[err])
|
||
|
: [err] "=r" (*err), EAX_EDX_RET(val, low, high)
|
||
|
: "c" (msr));
|
||
|
if (tracepoint_enabled(read_msr))
|
||
|
do_trace_read_msr(msr, EAX_EDX_VAL(val, low, high), *err);
|
||
|
return EAX_EDX_VAL(val, low, high);
|
||
|
}
|
||
|
|
||
|
/* Can be uninlined because referenced by paravirt */
|
||
|
static inline void notrace
|
||
|
native_write_msr(unsigned int msr, u32 low, u32 high)
|
||
|
{
|
||
|
__wrmsr(msr, low, high);
|
||
|
|
||
|
if (tracepoint_enabled(write_msr))
|
||
|
do_trace_write_msr(msr, ((u64)high << 32 | low), 0);
|
||
|
}
|
||
|
|
||
|
/* Can be uninlined because referenced by paravirt */
|
||
|
static inline int notrace
|
||
|
native_write_msr_safe(unsigned int msr, u32 low, u32 high)
|
||
|
{
|
||
|
int err;
|
||
|
|
||
|
asm volatile("1: wrmsr ; xor %[err],%[err]\n"
|
||
|
"2:\n\t"
|
||
|
_ASM_EXTABLE_TYPE_REG(1b, 2b, EX_TYPE_WRMSR_SAFE, %[err])
|
||
|
: [err] "=a" (err)
|
||
|
: "c" (msr), "0" (low), "d" (high)
|
||
|
: "memory");
|
||
|
if (tracepoint_enabled(write_msr))
|
||
|
do_trace_write_msr(msr, ((u64)high << 32 | low), err);
|
||
|
return err;
|
||
|
}
|
||
|
|
||
|
extern int rdmsr_safe_regs(u32 regs[8]);
|
||
|
extern int wrmsr_safe_regs(u32 regs[8]);
|
||
|
|
||
|
/**
|
||
|
* rdtsc() - returns the current TSC without ordering constraints
|
||
|
*
|
||
|
* rdtsc() returns the result of RDTSC as a 64-bit integer. The
|
||
|
* only ordering constraint it supplies is the ordering implied by
|
||
|
* "asm volatile": it will put the RDTSC in the place you expect. The
|
||
|
* CPU can and will speculatively execute that RDTSC, though, so the
|
||
|
* results can be non-monotonic if compared on different CPUs.
|
||
|
*/
|
||
|
static __always_inline unsigned long long rdtsc(void)
|
||
|
{
|
||
|
DECLARE_ARGS(val, low, high);
|
||
|
|
||
|
asm volatile("rdtsc" : EAX_EDX_RET(val, low, high));
|
||
|
|
||
|
return EAX_EDX_VAL(val, low, high);
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* rdtsc_ordered() - read the current TSC in program order
|
||
|
*
|
||
|
* rdtsc_ordered() returns the result of RDTSC as a 64-bit integer.
|
||
|
* It is ordered like a load to a global in-memory counter. It should
|
||
|
* be impossible to observe non-monotonic rdtsc_unordered() behavior
|
||
|
* across multiple CPUs as long as the TSC is synced.
|
||
|
*/
|
||
|
static __always_inline unsigned long long rdtsc_ordered(void)
|
||
|
{
|
||
|
DECLARE_ARGS(val, low, high);
|
||
|
|
||
|
/*
|
||
|
* The RDTSC instruction is not ordered relative to memory
|
||
|
* access. The Intel SDM and the AMD APM are both vague on this
|
||
|
* point, but empirically an RDTSC instruction can be
|
||
|
* speculatively executed before prior loads. An RDTSC
|
||
|
* immediately after an appropriate barrier appears to be
|
||
|
* ordered as a normal load, that is, it provides the same
|
||
|
* ordering guarantees as reading from a global memory location
|
||
|
* that some other imaginary CPU is updating continuously with a
|
||
|
* time stamp.
|
||
|
*
|
||
|
* Thus, use the preferred barrier on the respective CPU, aiming for
|
||
|
* RDTSCP as the default.
|
||
|
*/
|
||
|
asm volatile(ALTERNATIVE_2("rdtsc",
|
||
|
"lfence; rdtsc", X86_FEATURE_LFENCE_RDTSC,
|
||
|
"rdtscp", X86_FEATURE_RDTSCP)
|
||
|
: EAX_EDX_RET(val, low, high)
|
||
|
/* RDTSCP clobbers ECX with MSR_TSC_AUX. */
|
||
|
:: "ecx");
|
||
|
|
||
|
return EAX_EDX_VAL(val, low, high);
|
||
|
}
|
||
|
|
||
|
static inline unsigned long long native_read_pmc(int counter)
|
||
|
{
|
||
|
DECLARE_ARGS(val, low, high);
|
||
|
|
||
|
asm volatile("rdpmc" : EAX_EDX_RET(val, low, high) : "c" (counter));
|
||
|
if (tracepoint_enabled(rdpmc))
|
||
|
do_trace_rdpmc(counter, EAX_EDX_VAL(val, low, high), 0);
|
||
|
return EAX_EDX_VAL(val, low, high);
|
||
|
}
|
||
|
|
||
|
#ifdef CONFIG_PARAVIRT_XXL
|
||
|
#include <asm/paravirt.h>
|
||
|
#else
|
||
|
#include <linux/errno.h>
|
||
|
/*
|
||
|
* Access to machine-specific registers (available on 586 and better only)
|
||
|
* Note: the rd* operations modify the parameters directly (without using
|
||
|
* pointer indirection), this allows gcc to optimize better
|
||
|
*/
|
||
|
|
||
|
#define rdmsr(msr, low, high) \
|
||
|
do { \
|
||
|
u64 __val = native_read_msr((msr)); \
|
||
|
(void)((low) = (u32)__val); \
|
||
|
(void)((high) = (u32)(__val >> 32)); \
|
||
|
} while (0)
|
||
|
|
||
|
static inline void wrmsr(unsigned int msr, u32 low, u32 high)
|
||
|
{
|
||
|
native_write_msr(msr, low, high);
|
||
|
}
|
||
|
|
||
|
#define rdmsrl(msr, val) \
|
||
|
((val) = native_read_msr((msr)))
|
||
|
|
||
|
static inline void wrmsrl(unsigned int msr, u64 val)
|
||
|
{
|
||
|
native_write_msr(msr, (u32)(val & 0xffffffffULL), (u32)(val >> 32));
|
||
|
}
|
||
|
|
||
|
/* wrmsr with exception handling */
|
||
|
static inline int wrmsr_safe(unsigned int msr, u32 low, u32 high)
|
||
|
{
|
||
|
return native_write_msr_safe(msr, low, high);
|
||
|
}
|
||
|
|
||
|
/* rdmsr with exception handling */
|
||
|
#define rdmsr_safe(msr, low, high) \
|
||
|
({ \
|
||
|
int __err; \
|
||
|
u64 __val = native_read_msr_safe((msr), &__err); \
|
||
|
(*low) = (u32)__val; \
|
||
|
(*high) = (u32)(__val >> 32); \
|
||
|
__err; \
|
||
|
})
|
||
|
|
||
|
static inline int rdmsrl_safe(unsigned int msr, unsigned long long *p)
|
||
|
{
|
||
|
int err;
|
||
|
|
||
|
*p = native_read_msr_safe(msr, &err);
|
||
|
return err;
|
||
|
}
|
||
|
|
||
|
#define rdpmc(counter, low, high) \
|
||
|
do { \
|
||
|
u64 _l = native_read_pmc((counter)); \
|
||
|
(low) = (u32)_l; \
|
||
|
(high) = (u32)(_l >> 32); \
|
||
|
} while (0)
|
||
|
|
||
|
#define rdpmcl(counter, val) ((val) = native_read_pmc(counter))
|
||
|
|
||
|
#endif /* !CONFIG_PARAVIRT_XXL */
|
||
|
|
||
|
/*
|
||
|
* 64-bit version of wrmsr_safe():
|
||
|
*/
|
||
|
static inline int wrmsrl_safe(u32 msr, u64 val)
|
||
|
{
|
||
|
return wrmsr_safe(msr, (u32)val, (u32)(val >> 32));
|
||
|
}
|
||
|
|
||
|
struct msr *msrs_alloc(void);
|
||
|
void msrs_free(struct msr *msrs);
|
||
|
int msr_set_bit(u32 msr, u8 bit);
|
||
|
int msr_clear_bit(u32 msr, u8 bit);
|
||
|
|
||
|
#ifdef CONFIG_SMP
|
||
|
int rdmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h);
|
||
|
int wrmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h);
|
||
|
int rdmsrl_on_cpu(unsigned int cpu, u32 msr_no, u64 *q);
|
||
|
int wrmsrl_on_cpu(unsigned int cpu, u32 msr_no, u64 q);
|
||
|
void rdmsr_on_cpus(const struct cpumask *mask, u32 msr_no, struct msr *msrs);
|
||
|
void wrmsr_on_cpus(const struct cpumask *mask, u32 msr_no, struct msr *msrs);
|
||
|
int rdmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h);
|
||
|
int wrmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h);
|
||
|
int rdmsrl_safe_on_cpu(unsigned int cpu, u32 msr_no, u64 *q);
|
||
|
int wrmsrl_safe_on_cpu(unsigned int cpu, u32 msr_no, u64 q);
|
||
|
int rdmsr_safe_regs_on_cpu(unsigned int cpu, u32 regs[8]);
|
||
|
int wrmsr_safe_regs_on_cpu(unsigned int cpu, u32 regs[8]);
|
||
|
#else /* CONFIG_SMP */
|
||
|
static inline int rdmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h)
|
||
|
{
|
||
|
rdmsr(msr_no, *l, *h);
|
||
|
return 0;
|
||
|
}
|
||
|
static inline int wrmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h)
|
||
|
{
|
||
|
wrmsr(msr_no, l, h);
|
||
|
return 0;
|
||
|
}
|
||
|
static inline int rdmsrl_on_cpu(unsigned int cpu, u32 msr_no, u64 *q)
|
||
|
{
|
||
|
rdmsrl(msr_no, *q);
|
||
|
return 0;
|
||
|
}
|
||
|
static inline int wrmsrl_on_cpu(unsigned int cpu, u32 msr_no, u64 q)
|
||
|
{
|
||
|
wrmsrl(msr_no, q);
|
||
|
return 0;
|
||
|
}
|
||
|
static inline void rdmsr_on_cpus(const struct cpumask *m, u32 msr_no,
|
||
|
struct msr *msrs)
|
||
|
{
|
||
|
rdmsr_on_cpu(0, msr_no, &(msrs[0].l), &(msrs[0].h));
|
||
|
}
|
||
|
static inline void wrmsr_on_cpus(const struct cpumask *m, u32 msr_no,
|
||
|
struct msr *msrs)
|
||
|
{
|
||
|
wrmsr_on_cpu(0, msr_no, msrs[0].l, msrs[0].h);
|
||
|
}
|
||
|
static inline int rdmsr_safe_on_cpu(unsigned int cpu, u32 msr_no,
|
||
|
u32 *l, u32 *h)
|
||
|
{
|
||
|
return rdmsr_safe(msr_no, l, h);
|
||
|
}
|
||
|
static inline int wrmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h)
|
||
|
{
|
||
|
return wrmsr_safe(msr_no, l, h);
|
||
|
}
|
||
|
static inline int rdmsrl_safe_on_cpu(unsigned int cpu, u32 msr_no, u64 *q)
|
||
|
{
|
||
|
return rdmsrl_safe(msr_no, q);
|
||
|
}
|
||
|
static inline int wrmsrl_safe_on_cpu(unsigned int cpu, u32 msr_no, u64 q)
|
||
|
{
|
||
|
return wrmsrl_safe(msr_no, q);
|
||
|
}
|
||
|
static inline int rdmsr_safe_regs_on_cpu(unsigned int cpu, u32 regs[8])
|
||
|
{
|
||
|
return rdmsr_safe_regs(regs);
|
||
|
}
|
||
|
static inline int wrmsr_safe_regs_on_cpu(unsigned int cpu, u32 regs[8])
|
||
|
{
|
||
|
return wrmsr_safe_regs(regs);
|
||
|
}
|
||
|
#endif /* CONFIG_SMP */
|
||
|
#endif /* __ASSEMBLY__ */
|
||
|
#endif /* _ASM_X86_MSR_H */
|