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_init_timer(timer, tick) wrmsrl(timer, tick) 141 #define hv_init_timer_config(config, val) wrmsrl(config, val) 142 143 #define hv_get_simp(val) rdmsrl(HV_X64_MSR_SIMP, val) 144 #define hv_set_simp(val) wrmsrl(HV_X64_MSR_SIMP, val) 145 146 #define hv_get_siefp(val) rdmsrl(HV_X64_MSR_SIEFP, val) 147 #define hv_set_siefp(val) wrmsrl(HV_X64_MSR_SIEFP, val) 148 149 #define hv_get_synic_state(val) rdmsrl(HV_X64_MSR_SCONTROL, val) 150 #define hv_set_synic_state(val) wrmsrl(HV_X64_MSR_SCONTROL, val) 151 152 #define hv_get_vp_index(index) rdmsrl(HV_X64_MSR_VP_INDEX, index) 153 154 #define hv_get_synint_state(int_num, val) rdmsrl(int_num, val) 155 #define hv_set_synint_state(int_num, val) wrmsrl(int_num, val) 156 157 void hyperv_callback_vector(void); 158 #ifdef CONFIG_TRACING 159 #define trace_hyperv_callback_vector hyperv_callback_vector 160 #endif 161 void hyperv_vector_handler(struct pt_regs *regs); 162 void hv_setup_vmbus_irq(void (*handler)(void)); 163 void hv_remove_vmbus_irq(void); 164 165 void hv_setup_kexec_handler(void (*handler)(void)); 166 void hv_remove_kexec_handler(void); 167 void hv_setup_crash_handler(void (*handler)(struct pt_regs *regs)); 168 void hv_remove_crash_handler(void); 169 170 #if IS_ENABLED(CONFIG_HYPERV) 171 extern struct clocksource *hyperv_cs; 172 173 void hyperv_init(void); 174 void hyperv_report_panic(struct pt_regs *regs); 175 bool hv_is_hypercall_page_setup(void); 176 void hyperv_cleanup(void); 177 #endif 178 #ifdef CONFIG_HYPERV_TSCPAGE 179 struct ms_hyperv_tsc_page *hv_get_tsc_page(void); 180 static inline u64 hv_read_tsc_page(const struct ms_hyperv_tsc_page *tsc_pg) 181 { 182 u64 scale, offset, cur_tsc; 183 u32 sequence; 184 185 /* 186 * The protocol for reading Hyper-V TSC page is specified in Hypervisor 187 * Top-Level Functional Specification ver. 3.0 and above. To get the 188 * reference time we must do the following: 189 * - READ ReferenceTscSequence 190 * A special '0' value indicates the time source is unreliable and we 191 * need to use something else. The currently published specification 192 * versions (up to 4.0b) contain a mistake and wrongly claim '-1' 193 * instead of '0' as the special value, see commit c35b82ef0294. 194 * - ReferenceTime = 195 * ((RDTSC() * ReferenceTscScale) >> 64) + ReferenceTscOffset 196 * - READ ReferenceTscSequence again. In case its value has changed 197 * since our first reading we need to discard ReferenceTime and repeat 198 * the whole sequence as the hypervisor was updating the page in 199 * between. 200 */ 201 do { 202 sequence = READ_ONCE(tsc_pg->tsc_sequence); 203 if (!sequence) 204 return U64_MAX; 205 /* 206 * Make sure we read sequence before we read other values from 207 * TSC page. 208 */ 209 smp_rmb(); 210 211 scale = READ_ONCE(tsc_pg->tsc_scale); 212 offset = READ_ONCE(tsc_pg->tsc_offset); 213 cur_tsc = rdtsc_ordered(); 214 215 /* 216 * Make sure we read sequence after we read all other values 217 * from TSC page. 218 */ 219 smp_rmb(); 220 221 } while (READ_ONCE(tsc_pg->tsc_sequence) != sequence); 222 223 return mul_u64_u64_shr(cur_tsc, scale, 64) + offset; 224 } 225 226 #else 227 static inline struct ms_hyperv_tsc_page *hv_get_tsc_page(void) 228 { 229 return NULL; 230 } 231 #endif 232 #endif 233