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#ifndef _ASM_X86_MSHYPER_H
#define _ASM_X86_MSHYPER_H
#include <linux/types.h>
#include <linux/atomic.h>
#include <asm/hyperv.h>
/*
* The below CPUID leaves are present if VersionAndFeatures.HypervisorPresent
* is set by CPUID(HVCPUID_VERSION_FEATURES).
*/
enum hv_cpuid_function {
HVCPUID_VERSION_FEATURES = 0x00000001,
HVCPUID_VENDOR_MAXFUNCTION = 0x40000000,
HVCPUID_INTERFACE = 0x40000001,
/*
* The remaining functions depend on the value of
* HVCPUID_INTERFACE
*/
HVCPUID_VERSION = 0x40000002,
HVCPUID_FEATURES = 0x40000003,
HVCPUID_ENLIGHTENMENT_INFO = 0x40000004,
HVCPUID_IMPLEMENTATION_LIMITS = 0x40000005,
};
struct ms_hyperv_info {
u32 features;
u32 misc_features;
u32 hints;
u32 max_vp_index;
u32 max_lp_index;
};
extern struct ms_hyperv_info ms_hyperv;
/*
* Declare the MSR used to setup pages used to communicate with the hypervisor.
*/
union hv_x64_msr_hypercall_contents {
u64 as_uint64;
struct {
u64 enable:1;
u64 reserved:11;
u64 guest_physical_address:52;
};
};
/*
* TSC page layout.
*/
struct ms_hyperv_tsc_page {
volatile u32 tsc_sequence;
u32 reserved1;
volatile u64 tsc_scale;
volatile s64 tsc_offset;
u64 reserved2[509];
};
/*
* The guest OS needs to register the guest ID with the hypervisor.
* The guest ID is a 64 bit entity and the structure of this ID is
* specified in the Hyper-V specification:
*
* msdn.microsoft.com/en-us/library/windows/hardware/ff542653%28v=vs.85%29.aspx
*
* While the current guideline does not specify how Linux guest ID(s)
* need to be generated, our plan is to publish the guidelines for
* Linux and other guest operating systems that currently are hosted
* on Hyper-V. The implementation here conforms to this yet
* unpublished guidelines.
*
*
* Bit(s)
* 63 - Indicates if the OS is Open Source or not; 1 is Open Source
* 62:56 - Os Type; Linux is 0x100
* 55:48 - Distro specific identification
* 47:16 - Linux kernel version number
* 15:0 - Distro specific identification
*
*
*/
#define HV_LINUX_VENDOR_ID 0x8100
/*
* Generate the guest ID based on the guideline described above.
*/
static inline __u64 generate_guest_id(__u64 d_info1, __u64 kernel_version,
__u64 d_info2)
{
__u64 guest_id = 0;
guest_id = (((__u64)HV_LINUX_VENDOR_ID) << 48);
guest_id |= (d_info1 << 48);
guest_id |= (kernel_version << 16);
guest_id |= d_info2;
return guest_id;
}
/* Free the message slot and signal end-of-message if required */
static inline void vmbus_signal_eom(struct hv_message *msg, u32 old_msg_type)
{
/*
* On crash we're reading some other CPU's message page and we need
* to be careful: this other CPU may already had cleared the header
* and the host may already had delivered some other message there.
* In case we blindly write msg->header.message_type we're going
* to lose it. We can still lose a message of the same type but
* we count on the fact that there can only be one
* CHANNELMSG_UNLOAD_RESPONSE and we don't care about other messages
* on crash.
*/
if (cmpxchg(&msg->header.message_type, old_msg_type,
HVMSG_NONE) != old_msg_type)
return;
/*
* Make sure the write to MessageType (ie set to
* HVMSG_NONE) happens before we read the
* MessagePending and EOMing. Otherwise, the EOMing
* will not deliver any more messages since there is
* no empty slot
*/
mb();
if (msg->header.message_flags.msg_pending) {
/*
* This will cause message queue rescan to
* possibly deliver another msg from the
* hypervisor
*/
wrmsrl(HV_X64_MSR_EOM, 0);
}
}
#define hv_init_timer(timer, tick) wrmsrl(timer, tick)
#define hv_init_timer_config(config, val) wrmsrl(config, val)
#define hv_get_simp(val) rdmsrl(HV_X64_MSR_SIMP, val)
#define hv_set_simp(val) wrmsrl(HV_X64_MSR_SIMP, val)
#define hv_get_siefp(val) rdmsrl(HV_X64_MSR_SIEFP, val)
#define hv_set_siefp(val) wrmsrl(HV_X64_MSR_SIEFP, val)
#define hv_get_synic_state(val) rdmsrl(HV_X64_MSR_SCONTROL, val)
#define hv_set_synic_state(val) wrmsrl(HV_X64_MSR_SCONTROL, val)
#define hv_get_vp_index(index) rdmsrl(HV_X64_MSR_VP_INDEX, index)
#define hv_get_synint_state(int_num, val) rdmsrl(int_num, val)
#define hv_set_synint_state(int_num, val) wrmsrl(int_num, val)
void hyperv_callback_vector(void);
#ifdef CONFIG_TRACING
#define trace_hyperv_callback_vector hyperv_callback_vector
#endif
void hyperv_vector_handler(struct pt_regs *regs);
void hv_setup_vmbus_irq(void (*handler)(void));
void hv_remove_vmbus_irq(void);
void hv_setup_kexec_handler(void (*handler)(void));
void hv_remove_kexec_handler(void);
void hv_setup_crash_handler(void (*handler)(struct pt_regs *regs));
void hv_remove_crash_handler(void);
#if IS_ENABLED(CONFIG_HYPERV)
extern struct clocksource *hyperv_cs;
void hyperv_init(void);
void hyperv_report_panic(struct pt_regs *regs);
bool hv_is_hypercall_page_setup(void);
void hyperv_cleanup(void);
#endif
#ifdef CONFIG_HYPERV_TSCPAGE
struct ms_hyperv_tsc_page *hv_get_tsc_page(void);
static inline u64 hv_read_tsc_page(const struct ms_hyperv_tsc_page *tsc_pg)
{
u64 scale, offset, cur_tsc;
u32 sequence;
/*
* The protocol for reading Hyper-V TSC page is specified in Hypervisor
* Top-Level Functional Specification ver. 3.0 and above. To get the
* reference time we must do the following:
* - READ ReferenceTscSequence
* A special '0' value indicates the time source is unreliable and we
* need to use something else. The currently published specification
* versions (up to 4.0b) contain a mistake and wrongly claim '-1'
* instead of '0' as the special value, see commit c35b82ef0294.
* - ReferenceTime =
* ((RDTSC() * ReferenceTscScale) >> 64) + ReferenceTscOffset
* - READ ReferenceTscSequence again. In case its value has changed
* since our first reading we need to discard ReferenceTime and repeat
* the whole sequence as the hypervisor was updating the page in
* between.
*/
do {
sequence = READ_ONCE(tsc_pg->tsc_sequence);
if (!sequence)
return U64_MAX;
/*
* Make sure we read sequence before we read other values from
* TSC page.
*/
smp_rmb();
scale = READ_ONCE(tsc_pg->tsc_scale);
offset = READ_ONCE(tsc_pg->tsc_offset);
cur_tsc = rdtsc_ordered();
/*
* Make sure we read sequence after we read all other values
* from TSC page.
*/
smp_rmb();
} while (READ_ONCE(tsc_pg->tsc_sequence) != sequence);
return mul_u64_u64_shr(cur_tsc, scale, 64) + offset;
}
#else
static inline struct ms_hyperv_tsc_page *hv_get_tsc_page(void)
{
return NULL;
}
#endif
#endif
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