include/asm-generic/mshyperv.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2
   3 /*
   4  * Linux-specific definitions for managing interactions with Microsoft's
   5  * Hyper-V hypervisor. The definitions in this file are architecture
   6  * independent. See arch/<arch>/include/asm/mshyperv.h for definitions
   7  * that are specific to architecture <arch>.
   8  *
   9  * Definitions that are specified in the Hyper-V Top Level Functional
  10  * Spec (TLFS) should not go in this file, but should instead go in
  11  * hyperv-tlfs.h.
  12  *
  13  * Copyright (C) 2019, Microsoft, Inc.
  14  *
  15  * Author : Michael Kelley <mikelley@microsoft.com>
  16  */
  17
  18 #ifndef _ASM_GENERIC_MSHYPERV_H
  19 #define _ASM_GENERIC_MSHYPERV_H
  20
  21 #include <linux/types.h>
  22 #include <linux/atomic.h>
  23 #include <linux/bitops.h>
  24 #include <acpi/acpi_numa.h>
  25 #include <linux/cpumask.h>
  26 #include <linux/nmi.h>
  27 #include <asm/ptrace.h>
  28 #include <asm/hyperv-tlfs.h>
  29
  30 #define VTPM_BASE_ADDRESS 0xfed40000
  31
  32 struct ms_hyperv_info {
  33         u32 features;
  34         u32 priv_high;
  35         u32 misc_features;
  36         u32 hints;
  37         u32 nested_features;
  38         u32 max_vp_index;
  39         u32 max_lp_index;
  40         u8 vtl;
  41         union {
  42                 u32 isolation_config_a;
  43                 struct {
  44                         u32 paravisor_present : 1;
  45                         u32 reserved_a1 : 31;
  46                 };
  47         };
  48         union {
  49                 u32 isolation_config_b;
  50                 struct {
  51                         u32 cvm_type : 4;
  52                         u32 reserved_b1 : 1;
  53                         u32 shared_gpa_boundary_active : 1;
  54                         u32 shared_gpa_boundary_bits : 6;
  55                         u32 reserved_b2 : 20;
  56                 };
  57         };
  58         u64 shared_gpa_boundary;
  59 };
  60 extern struct ms_hyperv_info ms_hyperv;
  61 extern bool hv_nested;
  62
  63 extern void * __percpu *hyperv_pcpu_input_arg;
  64 extern void * __percpu *hyperv_pcpu_output_arg;
  65
  66 extern u64 hv_do_hypercall(u64 control, void *inputaddr, void *outputaddr);
  67 extern u64 hv_do_fast_hypercall8(u16 control, u64 input8);
  68 bool hv_isolation_type_snp(void);
  69 bool hv_isolation_type_tdx(void);
  70
  71 static inline struct hv_proximity_domain_info hv_numa_node_to_pxm_info(int node)
  72 {
  73         struct hv_proximity_domain_info pxm_info = {};
  74
  75         if (node != NUMA_NO_NODE) {
  76                 pxm_info.domain_id = node_to_pxm(node);
  77                 pxm_info.flags.proximity_info_valid = 1;
  78                 pxm_info.flags.proximity_preferred = 1;
  79         }
  80
  81         return pxm_info;
  82 }
  83
  84 /* Helper functions that provide a consistent pattern for checking Hyper-V hypercall status. */
  85 static inline int hv_result(u64 status)
  86 {
  87         return status & HV_HYPERCALL_RESULT_MASK;
  88 }
  89
  90 static inline bool hv_result_success(u64 status)
  91 {
  92         return hv_result(status) == HV_STATUS_SUCCESS;
  93 }
  94
  95 static inline unsigned int hv_repcomp(u64 status)
  96 {
  97         /* Bits [43:32] of status have 'Reps completed' data. */
  98         return (status & HV_HYPERCALL_REP_COMP_MASK) >>
  99                          HV_HYPERCALL_REP_COMP_OFFSET;
 100 }
 101
 102 /*
 103  * Rep hypercalls. Callers of this functions are supposed to ensure that
 104  * rep_count and varhead_size comply with Hyper-V hypercall definition.
 105  */
 106 static inline u64 hv_do_rep_hypercall(u16 code, u16 rep_count, u16 varhead_size,
 107                                       void *input, void *output)
 108 {
 109         u64 control = code;
 110         u64 status;
 111         u16 rep_comp;
 112
 113         control |= (u64)varhead_size << HV_HYPERCALL_VARHEAD_OFFSET;
 114         control |= (u64)rep_count << HV_HYPERCALL_REP_COMP_OFFSET;
 115
 116         do {
 117                 status = hv_do_hypercall(control, input, output);
 118                 if (!hv_result_success(status))
 119                         return status;
 120
 121                 rep_comp = hv_repcomp(status);
 122
 123                 control &= ~HV_HYPERCALL_REP_START_MASK;
 124                 control |= (u64)rep_comp << HV_HYPERCALL_REP_START_OFFSET;
 125
 126                 touch_nmi_watchdog();
 127         } while (rep_comp < rep_count);
 128
 129         return status;
 130 }
 131
 132 /* Generate the guest OS identifier as described in the Hyper-V TLFS */
 133 static inline u64 hv_generate_guest_id(u64 kernel_version)
 134 {
 135         u64 guest_id;
 136
 137         guest_id = (((u64)HV_LINUX_VENDOR_ID) << 48);
 138         guest_id |= (kernel_version << 16);
 139
 140         return guest_id;
 141 }
 142
 143 /* Free the message slot and signal end-of-message if required */
 144 static inline void vmbus_signal_eom(struct hv_message *msg, u32 old_msg_type)
 145 {
 146         /*
 147          * On crash we're reading some other CPU's message page and we need
 148          * to be careful: this other CPU may already had cleared the header
 149          * and the host may already had delivered some other message there.
 150          * In case we blindly write msg->header.message_type we're going
 151          * to lose it. We can still lose a message of the same type but
 152          * we count on the fact that there can only be one
 153          * CHANNELMSG_UNLOAD_RESPONSE and we don't care about other messages
 154          * on crash.
 155          */
 156         if (cmpxchg(&msg->header.message_type, old_msg_type,
 157                     HVMSG_NONE) != old_msg_type)
 158                 return;
 159
 160         /*
 161          * The cmxchg() above does an implicit memory barrier to
 162          * ensure the write to MessageType (ie set to
 163          * HVMSG_NONE) happens before we read the
 164          * MessagePending and EOMing. Otherwise, the EOMing
 165          * will not deliver any more messages since there is
 166          * no empty slot
 167          */
 168         if (msg->header.message_flags.msg_pending) {
 169                 /*
 170                  * This will cause message queue rescan to
 171                  * possibly deliver another msg from the
 172                  * hypervisor
 173                  */
 174                 hv_set_msr(HV_MSR_EOM, 0);
 175         }
 176 }
 177
 178 int hv_get_hypervisor_version(union hv_hypervisor_version_info *info);
 179
 180 void hv_setup_vmbus_handler(void (*handler)(void));
 181 void hv_remove_vmbus_handler(void);
 182 void hv_setup_stimer0_handler(void (*handler)(void));
 183 void hv_remove_stimer0_handler(void);
 184
 185 void hv_setup_kexec_handler(void (*handler)(void));
 186 void hv_remove_kexec_handler(void);
 187 void hv_setup_crash_handler(void (*handler)(struct pt_regs *regs));
 188 void hv_remove_crash_handler(void);
 189
 190 extern int vmbus_interrupt;
 191 extern int vmbus_irq;
 192
 193 extern bool hv_root_partition;
 194
 195 #if IS_ENABLED(CONFIG_HYPERV)
 196 /*
 197  * Hypervisor's notion of virtual processor ID is different from
 198  * Linux' notion of CPU ID. This information can only be retrieved
 199  * in the context of the calling CPU. Setup a map for easy access
 200  * to this information.
 201  */
 202 extern u32 *hv_vp_index;
 203 extern u32 hv_max_vp_index;
 204
 205 extern u64 (*hv_read_reference_counter)(void);
 206
 207 /* Sentinel value for an uninitialized entry in hv_vp_index array */
 208 #define VP_INVAL        U32_MAX
 209
 210 int __init hv_common_init(void);
 211 void __init hv_common_free(void);
 212 void __init ms_hyperv_late_init(void);
 213 int hv_common_cpu_init(unsigned int cpu);
 214 int hv_common_cpu_die(unsigned int cpu);
 215
 216 void *hv_alloc_hyperv_page(void);
 217 void *hv_alloc_hyperv_zeroed_page(void);
 218 void hv_free_hyperv_page(void *addr);
 219
 220 /**
 221  * hv_cpu_number_to_vp_number() - Map CPU to VP.
 222  * @cpu_number: CPU number in Linux terms
 223  *
 224  * This function returns the mapping between the Linux processor
 225  * number and the hypervisor's virtual processor number, useful
 226  * in making hypercalls and such that talk about specific
 227  * processors.
 228  *
 229  * Return: Virtual processor number in Hyper-V terms
 230  */
 231 static inline int hv_cpu_number_to_vp_number(int cpu_number)
 232 {
 233         return hv_vp_index[cpu_number];
 234 }
 235
 236 static inline int __cpumask_to_vpset(struct hv_vpset *vpset,
 237                                     const struct cpumask *cpus,
 238                                     bool (*func)(int cpu))
 239 {
 240         int cpu, vcpu, vcpu_bank, vcpu_offset, nr_bank = 1;
 241         int max_vcpu_bank = hv_max_vp_index / HV_VCPUS_PER_SPARSE_BANK;
 242
 243         /* vpset.valid_bank_mask can represent up to HV_MAX_SPARSE_VCPU_BANKS banks */
 244         if (max_vcpu_bank >= HV_MAX_SPARSE_VCPU_BANKS)
 245                 return 0;
 246
 247         /*
 248          * Clear all banks up to the maximum possible bank as hv_tlb_flush_ex
 249          * structs are not cleared between calls, we risk flushing unneeded
 250          * vCPUs otherwise.
 251          */
 252         for (vcpu_bank = 0; vcpu_bank <= max_vcpu_bank; vcpu_bank++)
 253                 vpset->bank_contents[vcpu_bank] = 0;
 254
 255         /*
 256          * Some banks may end up being empty but this is acceptable.
 257          */
 258         for_each_cpu(cpu, cpus) {
 259                 if (func && func(cpu))
 260                         continue;
 261                 vcpu = hv_cpu_number_to_vp_number(cpu);
 262                 if (vcpu == VP_INVAL)
 263                         return -1;
 264                 vcpu_bank = vcpu / HV_VCPUS_PER_SPARSE_BANK;
 265                 vcpu_offset = vcpu % HV_VCPUS_PER_SPARSE_BANK;
 266                 __set_bit(vcpu_offset, (unsigned long *)
 267                           &vpset->bank_contents[vcpu_bank]);
 268                 if (vcpu_bank >= nr_bank)
 269                         nr_bank = vcpu_bank + 1;
 270         }
 271         vpset->valid_bank_mask = GENMASK_ULL(nr_bank - 1, 0);
 272         return nr_bank;
 273 }
 274
 275 /*
 276  * Convert a Linux cpumask into a Hyper-V VPset. In the _skip variant,
 277  * 'func' is called for each CPU present in cpumask.  If 'func' returns
 278  * true, that CPU is skipped -- i.e., that CPU from cpumask is *not*
 279  * added to the Hyper-V VPset. If 'func' is NULL, no CPUs are
 280  * skipped.
 281  */
 282 static inline int cpumask_to_vpset(struct hv_vpset *vpset,
 283                                     const struct cpumask *cpus)
 284 {
 285         return __cpumask_to_vpset(vpset, cpus, NULL);
 286 }
 287
 288 static inline int cpumask_to_vpset_skip(struct hv_vpset *vpset,
 289                                     const struct cpumask *cpus,
 290                                     bool (*func)(int cpu))
 291 {
 292         return __cpumask_to_vpset(vpset, cpus, func);
 293 }
 294
 295 void hyperv_report_panic(struct pt_regs *regs, long err, bool in_die);
 296 bool hv_is_hyperv_initialized(void);
 297 bool hv_is_hibernation_supported(void);
 298 enum hv_isolation_type hv_get_isolation_type(void);
 299 bool hv_is_isolation_supported(void);
 300 bool hv_isolation_type_snp(void);
 301 u64 hv_ghcb_hypercall(u64 control, void *input, void *output, u32 input_size);
 302 u64 hv_tdx_hypercall(u64 control, u64 param1, u64 param2);
 303 void hyperv_cleanup(void);
 304 bool hv_query_ext_cap(u64 cap_query);
 305 void hv_setup_dma_ops(struct device *dev, bool coherent);
 306 #else /* CONFIG_HYPERV */
 307 static inline bool hv_is_hyperv_initialized(void) { return false; }
 308 static inline bool hv_is_hibernation_supported(void) { return false; }
 309 static inline void hyperv_cleanup(void) {}
 310 static inline void ms_hyperv_late_init(void) {}
 311 static inline bool hv_is_isolation_supported(void) { return false; }
 312 static inline enum hv_isolation_type hv_get_isolation_type(void)
 313 {
 314         return HV_ISOLATION_TYPE_NONE;
 315 }
 316 #endif /* CONFIG_HYPERV */
 317
 318 #endif