1 #ifndef _ASM_X86_MSHYPER_H 2 #define _ASM_X86_MSHYPER_H 3 4 #include <linux/types.h> 5 #include <linux/interrupt.h> 6 #include <linux/clocksource.h> 7 #include <asm/hyperv.h> 8 9 /* 10 * The below CPUID leaves are present if VersionAndFeatures.HypervisorPresent 11 * is set by CPUID(HVCPUID_VERSION_FEATURES). 12 */ 13 enum hv_cpuid_function { 14 HVCPUID_VERSION_FEATURES = 0x00000001, 15 HVCPUID_VENDOR_MAXFUNCTION = 0x40000000, 16 HVCPUID_INTERFACE = 0x40000001, 17 18 /* 19 * The remaining functions depend on the value of 20 * HVCPUID_INTERFACE 21 */ 22 HVCPUID_VERSION = 0x40000002, 23 HVCPUID_FEATURES = 0x40000003, 24 HVCPUID_ENLIGHTENMENT_INFO = 0x40000004, 25 HVCPUID_IMPLEMENTATION_LIMITS = 0x40000005, 26 }; 27 28 struct ms_hyperv_info { 29 u32 features; 30 u32 misc_features; 31 u32 hints; 32 }; 33 34 extern struct ms_hyperv_info ms_hyperv; 35 36 /* 37 * Declare the MSR used to setup pages used to communicate with the hypervisor. 38 */ 39 union hv_x64_msr_hypercall_contents { 40 u64 as_uint64; 41 struct { 42 u64 enable:1; 43 u64 reserved:11; 44 u64 guest_physical_address:52; 45 }; 46 }; 47 48 /* 49 * TSC page layout. 50 */ 51 52 struct ms_hyperv_tsc_page { 53 volatile u32 tsc_sequence; 54 u32 reserved1; 55 volatile u64 tsc_scale; 56 volatile s64 tsc_offset; 57 u64 reserved2[509]; 58 }; 59 60 /* 61 * The guest OS needs to register the guest ID with the hypervisor. 62 * The guest ID is a 64 bit entity and the structure of this ID is 63 * specified in the Hyper-V specification: 64 * 65 * msdn.microsoft.com/en-us/library/windows/hardware/ff542653%28v=vs.85%29.aspx 66 * 67 * While the current guideline does not specify how Linux guest ID(s) 68 * need to be generated, our plan is to publish the guidelines for 69 * Linux and other guest operating systems that currently are hosted 70 * on Hyper-V. The implementation here conforms to this yet 71 * unpublished guidelines. 72 * 73 * 74 * Bit(s) 75 * 63 - Indicates if the OS is Open Source or not; 1 is Open Source 76 * 62:56 - Os Type; Linux is 0x100 77 * 55:48 - Distro specific identification 78 * 47:16 - Linux kernel version number 79 * 15:0 - Distro specific identification 80 * 81 * 82 */ 83 84 #define HV_LINUX_VENDOR_ID 0x8100 85 86 /* 87 * Generate the guest ID based on the guideline described above. 88 */ 89 90 static inline __u64 generate_guest_id(__u64 d_info1, __u64 kernel_version, 91 __u64 d_info2) 92 { 93 __u64 guest_id = 0; 94 95 guest_id = (((__u64)HV_LINUX_VENDOR_ID) << 48); 96 guest_id |= (d_info1 << 48); 97 guest_id |= (kernel_version << 16); 98 guest_id |= d_info2; 99 100 return guest_id; 101 } 102 103 104 /* Free the message slot and signal end-of-message if required */ 105 static inline void vmbus_signal_eom(struct hv_message *msg, u32 old_msg_type) 106 { 107 /* 108 * On crash we're reading some other CPU's message page and we need 109 * to be careful: this other CPU may already had cleared the header 110 * and the host may already had delivered some other message there. 111 * In case we blindly write msg->header.message_type we're going 112 * to lose it. We can still lose a message of the same type but 113 * we count on the fact that there can only be one 114 * CHANNELMSG_UNLOAD_RESPONSE and we don't care about other messages 115 * on crash. 116 */ 117 if (cmpxchg(&msg->header.message_type, old_msg_type, 118 HVMSG_NONE) != old_msg_type) 119 return; 120 121 /* 122 * Make sure the write to MessageType (ie set to 123 * HVMSG_NONE) happens before we read the 124 * MessagePending and EOMing. Otherwise, the EOMing 125 * will not deliver any more messages since there is 126 * no empty slot 127 */ 128 mb(); 129 130 if (msg->header.message_flags.msg_pending) { 131 /* 132 * This will cause message queue rescan to 133 * possibly deliver another msg from the 134 * hypervisor 135 */ 136 wrmsrl(HV_X64_MSR_EOM, 0); 137 } 138 } 139 140 #define hv_get_current_tick(tick) rdmsrl(HV_X64_MSR_TIME_REF_COUNT, tick) 141 #define hv_init_timer(timer, tick) wrmsrl(timer, tick) 142 #define hv_init_timer_config(config, val) wrmsrl(config, val) 143 144 #define hv_get_simp(val) rdmsrl(HV_X64_MSR_SIMP, val) 145 #define hv_set_simp(val) wrmsrl(HV_X64_MSR_SIMP, val) 146 147 #define hv_get_siefp(val) rdmsrl(HV_X64_MSR_SIEFP, val) 148 #define hv_set_siefp(val) wrmsrl(HV_X64_MSR_SIEFP, val) 149 150 #define hv_get_synic_state(val) rdmsrl(HV_X64_MSR_SCONTROL, val) 151 #define hv_set_synic_state(val) wrmsrl(HV_X64_MSR_SCONTROL, val) 152 153 #define hv_get_vp_index(index) rdmsrl(HV_X64_MSR_VP_INDEX, index) 154 155 #define hv_get_synint_state(int_num, val) rdmsrl(int_num, val) 156 #define hv_set_synint_state(int_num, val) wrmsrl(int_num, val) 157 158 void hyperv_callback_vector(void); 159 #ifdef CONFIG_TRACING 160 #define trace_hyperv_callback_vector hyperv_callback_vector 161 #endif 162 void hyperv_vector_handler(struct pt_regs *regs); 163 void hv_setup_vmbus_irq(void (*handler)(void)); 164 void hv_remove_vmbus_irq(void); 165 166 void hv_setup_kexec_handler(void (*handler)(void)); 167 void hv_remove_kexec_handler(void); 168 void hv_setup_crash_handler(void (*handler)(struct pt_regs *regs)); 169 void hv_remove_crash_handler(void); 170 171 #if IS_ENABLED(CONFIG_HYPERV) 172 extern struct clocksource *hyperv_cs; 173 174 void hyperv_init(void); 175 void hyperv_report_panic(struct pt_regs *regs); 176 bool hv_is_hypercall_page_setup(void); 177 void hyperv_cleanup(void); 178 #endif 179 #ifdef CONFIG_HYPERV_TSCPAGE 180 struct ms_hyperv_tsc_page *hv_get_tsc_page(void); 181 static inline u64 hv_read_tsc_page(const struct ms_hyperv_tsc_page *tsc_pg) 182 { 183 u64 scale, offset, cur_tsc; 184 u32 sequence; 185 186 /* 187 * The protocol for reading Hyper-V TSC page is specified in Hypervisor 188 * Top-Level Functional Specification ver. 3.0 and above. To get the 189 * reference time we must do the following: 190 * - READ ReferenceTscSequence 191 * A special '0' value indicates the time source is unreliable and we 192 * need to use something else. The currently published specification 193 * versions (up to 4.0b) contain a mistake and wrongly claim '-1' 194 * instead of '0' as the special value, see commit c35b82ef0294. 195 * - ReferenceTime = 196 * ((RDTSC() * ReferenceTscScale) >> 64) + ReferenceTscOffset 197 * - READ ReferenceTscSequence again. In case its value has changed 198 * since our first reading we need to discard ReferenceTime and repeat 199 * the whole sequence as the hypervisor was updating the page in 200 * between. 201 */ 202 do { 203 sequence = READ_ONCE(tsc_pg->tsc_sequence); 204 if (!sequence) 205 return U64_MAX; 206 /* 207 * Make sure we read sequence before we read other values from 208 * TSC page. 209 */ 210 smp_rmb(); 211 212 scale = READ_ONCE(tsc_pg->tsc_scale); 213 offset = READ_ONCE(tsc_pg->tsc_offset); 214 cur_tsc = rdtsc_ordered(); 215 216 /* 217 * Make sure we read sequence after we read all other values 218 * from TSC page. 219 */ 220 smp_rmb(); 221 222 } while (READ_ONCE(tsc_pg->tsc_sequence) != sequence); 223 224 return mul_u64_u64_shr(cur_tsc, scale, 64) + offset; 225 } 226 227 #else 228 static inline struct ms_hyperv_tsc_page *hv_get_tsc_page(void) 229 { 230 return NULL; 231 } 232 #endif 233 #endif 234