/* SPDX-License-Identifier: GPL-2.0 */ #ifndef _ASM_X86_MSHYPER_H #define _ASM_X86_MSHYPER_H #include #include #include #include #include /* * 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; extern void *hv_hypercall_pg; static inline u64 hv_do_hypercall(u64 control, void *input, void *output) { u64 input_address = input ? virt_to_phys(input) : 0; u64 output_address = output ? virt_to_phys(output) : 0; u64 hv_status; #ifdef CONFIG_X86_64 if (!hv_hypercall_pg) return U64_MAX; __asm__ __volatile__("mov %4, %%r8\n" "call *%5" : "=a" (hv_status), ASM_CALL_CONSTRAINT, "+c" (control), "+d" (input_address) : "r" (output_address), "m" (hv_hypercall_pg) : "cc", "memory", "r8", "r9", "r10", "r11"); #else u32 input_address_hi = upper_32_bits(input_address); u32 input_address_lo = lower_32_bits(input_address); u32 output_address_hi = upper_32_bits(output_address); u32 output_address_lo = lower_32_bits(output_address); if (!hv_hypercall_pg) return U64_MAX; __asm__ __volatile__("call *%7" : "=A" (hv_status), "+c" (input_address_lo), ASM_CALL_CONSTRAINT : "A" (control), "b" (input_address_hi), "D"(output_address_hi), "S"(output_address_lo), "m" (hv_hypercall_pg) : "cc", "memory"); #endif /* !x86_64 */ return hv_status; } #define HV_HYPERCALL_RESULT_MASK GENMASK_ULL(15, 0) #define HV_HYPERCALL_FAST_BIT BIT(16) #define HV_HYPERCALL_VARHEAD_OFFSET 17 #define HV_HYPERCALL_REP_COMP_OFFSET 32 #define HV_HYPERCALL_REP_COMP_MASK GENMASK_ULL(43, 32) #define HV_HYPERCALL_REP_START_OFFSET 48 #define HV_HYPERCALL_REP_START_MASK GENMASK_ULL(59, 48) /* Fast hypercall with 8 bytes of input and no output */ static inline u64 hv_do_fast_hypercall8(u16 code, u64 input1) { u64 hv_status, control = (u64)code | HV_HYPERCALL_FAST_BIT; #ifdef CONFIG_X86_64 { __asm__ __volatile__("call *%4" : "=a" (hv_status), ASM_CALL_CONSTRAINT, "+c" (control), "+d" (input1) : "m" (hv_hypercall_pg) : "cc", "r8", "r9", "r10", "r11"); } #else { u32 input1_hi = upper_32_bits(input1); u32 input1_lo = lower_32_bits(input1); __asm__ __volatile__ ("call *%5" : "=A"(hv_status), "+c"(input1_lo), ASM_CALL_CONSTRAINT : "A" (control), "b" (input1_hi), "m" (hv_hypercall_pg) : "cc", "edi", "esi"); } #endif return hv_status; } /* * Rep hypercalls. Callers of this functions are supposed to ensure that * rep_count and varhead_size comply with Hyper-V hypercall definition. */ static inline u64 hv_do_rep_hypercall(u16 code, u16 rep_count, u16 varhead_size, void *input, void *output) { u64 control = code; u64 status; u16 rep_comp; control |= (u64)varhead_size << HV_HYPERCALL_VARHEAD_OFFSET; control |= (u64)rep_count << HV_HYPERCALL_REP_COMP_OFFSET; do { status = hv_do_hypercall(control, input, output); if ((status & HV_HYPERCALL_RESULT_MASK) != HV_STATUS_SUCCESS) return status; /* Bits 32-43 of status have 'Reps completed' data. */ rep_comp = (status & HV_HYPERCALL_REP_COMP_MASK) >> HV_HYPERCALL_REP_COMP_OFFSET; control &= ~HV_HYPERCALL_REP_START_MASK; control |= (u64)rep_comp << HV_HYPERCALL_REP_START_OFFSET; touch_nmi_watchdog(); } while (rep_comp < rep_count); return status; } /* * Hypervisor's notion of virtual processor ID is different from * Linux' notion of CPU ID. This information can only be retrieved * in the context of the calling CPU. Setup a map for easy access * to this information. */ extern u32 *hv_vp_index; extern u32 hv_max_vp_index; /** * hv_cpu_number_to_vp_number() - Map CPU to VP. * @cpu_number: CPU number in Linux terms * * This function returns the mapping between the Linux processor * number and the hypervisor's virtual processor number, useful * in making hypercalls and such that talk about specific * processors. * * Return: Virtual processor number in Hyper-V terms */ static inline int hv_cpu_number_to_vp_number(int cpu_number) { return hv_vp_index[cpu_number]; } void hyperv_init(void); void hyperv_setup_mmu_ops(void); void hyper_alloc_mmu(void); void hyperv_report_panic(struct pt_regs *regs, long err); bool hv_is_hypercall_page_setup(void); void hyperv_cleanup(void); #else /* CONFIG_HYPERV */ static inline void hyperv_init(void) {} static inline bool hv_is_hypercall_page_setup(void) { return false; } static inline void hyperv_cleanup(void) {} static inline void hyperv_setup_mmu_ops(void) {} #endif /* CONFIG_HYPERV */ #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