v4.19.13 snapshot.
diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyperv.h
new file mode 100644
index 0000000..f377044
--- /dev/null
+++ b/arch/x86/include/asm/mshyperv.h
@@ -0,0 +1,442 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_X86_MSHYPER_H
+#define _ASM_X86_MSHYPER_H
+
+#include <linux/types.h>
+#include <linux/atomic.h>
+#include <linux/nmi.h>
+#include <asm/io.h>
+#include <asm/hyperv-tlfs.h>
+#include <asm/nospec-branch.h>
+
+#define VP_INVAL U32_MAX
+
+struct ms_hyperv_info {
+ u32 features;
+ u32 misc_features;
+ u32 hints;
+ u32 nested_features;
+ u32 max_vp_index;
+ u32 max_lp_index;
+};
+
+extern struct ms_hyperv_info ms_hyperv;
+
+/*
+ * Generate the guest ID.
+ */
+
+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(HV_X64_MSR_STIMER0_COUNT + (2*timer), tick)
+#define hv_init_timer_config(timer, val) \
+ wrmsrl(HV_X64_MSR_STIMER0_CONFIG + (2*timer), 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(HV_X64_MSR_SINT0 + int_num, val)
+#define hv_set_synint_state(int_num, val) \
+ wrmsrl(HV_X64_MSR_SINT0 + int_num, val)
+
+#define hv_get_crash_ctl(val) \
+ rdmsrl(HV_X64_MSR_CRASH_CTL, val)
+
+void hyperv_callback_vector(void);
+void hyperv_reenlightenment_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);
+
+/*
+ * Routines for stimer0 Direct Mode handling.
+ * On x86/x64, there are no percpu actions to take.
+ */
+void hv_stimer0_vector_handler(struct pt_regs *regs);
+void hv_stimer0_callback_vector(void);
+int hv_setup_stimer0_irq(int *irq, int *vector, void (*handler)(void));
+void hv_remove_stimer0_irq(int irq);
+
+static inline void hv_enable_stimer0_percpu_irq(int irq) {}
+static inline void hv_disable_stimer0_percpu_irq(int irq) {}
+
+
+#if IS_ENABLED(CONFIG_HYPERV)
+extern struct clocksource *hyperv_cs;
+extern void *hv_hypercall_pg;
+extern void __percpu **hyperv_pcpu_input_arg;
+
+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_NOSPEC
+ : "=a" (hv_status), ASM_CALL_CONSTRAINT,
+ "+c" (control), "+d" (input_address)
+ : "r" (output_address),
+ THUNK_TARGET(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_NOSPEC
+ : "=A" (hv_status),
+ "+c" (input_address_lo), ASM_CALL_CONSTRAINT
+ : "A" (control),
+ "b" (input_address_hi),
+ "D"(output_address_hi), "S"(output_address_lo),
+ THUNK_TARGET(hv_hypercall_pg)
+ : "cc", "memory");
+#endif /* !x86_64 */
+ return hv_status;
+}
+
+/* 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_NOSPEC
+ : "=a" (hv_status), ASM_CALL_CONSTRAINT,
+ "+c" (control), "+d" (input1)
+ : THUNK_TARGET(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_NOSPEC
+ : "=A"(hv_status),
+ "+c"(input1_lo),
+ ASM_CALL_CONSTRAINT
+ : "A" (control),
+ "b" (input1_hi),
+ THUNK_TARGET(hv_hypercall_pg)
+ : "cc", "edi", "esi");
+ }
+#endif
+ return hv_status;
+}
+
+/* Fast hypercall with 16 bytes of input */
+static inline u64 hv_do_fast_hypercall16(u16 code, u64 input1, u64 input2)
+{
+ u64 hv_status, control = (u64)code | HV_HYPERCALL_FAST_BIT;
+
+#ifdef CONFIG_X86_64
+ {
+ __asm__ __volatile__("mov %4, %%r8\n"
+ CALL_NOSPEC
+ : "=a" (hv_status), ASM_CALL_CONSTRAINT,
+ "+c" (control), "+d" (input1)
+ : "r" (input2),
+ THUNK_TARGET(hv_hypercall_pg)
+ : "cc", "r8", "r9", "r10", "r11");
+ }
+#else
+ {
+ u32 input1_hi = upper_32_bits(input1);
+ u32 input1_lo = lower_32_bits(input1);
+ u32 input2_hi = upper_32_bits(input2);
+ u32 input2_lo = lower_32_bits(input2);
+
+ __asm__ __volatile__ (CALL_NOSPEC
+ : "=A"(hv_status),
+ "+c"(input1_lo), ASM_CALL_CONSTRAINT
+ : "A" (control), "b" (input1_hi),
+ "D"(input2_hi), "S"(input2_lo),
+ THUNK_TARGET(hv_hypercall_pg)
+ : "cc");
+ }
+#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;
+extern struct hv_vp_assist_page **hv_vp_assist_page;
+
+static inline struct hv_vp_assist_page *hv_get_vp_assist_page(unsigned int cpu)
+{
+ if (!hv_vp_assist_page)
+ return NULL;
+
+ return hv_vp_assist_page[cpu];
+}
+
+/**
+ * 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];
+}
+
+static inline int cpumask_to_vpset(struct hv_vpset *vpset,
+ const struct cpumask *cpus)
+{
+ int cpu, vcpu, vcpu_bank, vcpu_offset, nr_bank = 1;
+
+ /* valid_bank_mask can represent up to 64 banks */
+ if (hv_max_vp_index / 64 >= 64)
+ return 0;
+
+ /*
+ * Clear all banks up to the maximum possible bank as hv_tlb_flush_ex
+ * structs are not cleared between calls, we risk flushing unneeded
+ * vCPUs otherwise.
+ */
+ for (vcpu_bank = 0; vcpu_bank <= hv_max_vp_index / 64; vcpu_bank++)
+ vpset->bank_contents[vcpu_bank] = 0;
+
+ /*
+ * Some banks may end up being empty but this is acceptable.
+ */
+ for_each_cpu(cpu, cpus) {
+ vcpu = hv_cpu_number_to_vp_number(cpu);
+ if (vcpu == VP_INVAL)
+ return -1;
+ vcpu_bank = vcpu / 64;
+ vcpu_offset = vcpu % 64;
+ __set_bit(vcpu_offset, (unsigned long *)
+ &vpset->bank_contents[vcpu_bank]);
+ if (vcpu_bank >= nr_bank)
+ nr_bank = vcpu_bank + 1;
+ }
+ vpset->valid_bank_mask = GENMASK_ULL(nr_bank - 1, 0);
+ return nr_bank;
+}
+
+void __init hyperv_init(void);
+void hyperv_setup_mmu_ops(void);
+void hyperv_report_panic(struct pt_regs *regs, long err);
+void hyperv_report_panic_msg(phys_addr_t pa, size_t size);
+bool hv_is_hyperv_initialized(void);
+void hyperv_cleanup(void);
+
+void hyperv_reenlightenment_intr(struct pt_regs *regs);
+void set_hv_tscchange_cb(void (*cb)(void));
+void clear_hv_tscchange_cb(void);
+void hyperv_stop_tsc_emulation(void);
+int hyperv_flush_guest_mapping(u64 as);
+
+#ifdef CONFIG_X86_64
+void hv_apic_init(void);
+#else
+static inline void hv_apic_init(void) {}
+#endif
+
+#else /* CONFIG_HYPERV */
+static inline void hyperv_init(void) {}
+static inline bool hv_is_hyperv_initialized(void) { return false; }
+static inline void hyperv_cleanup(void) {}
+static inline void hyperv_setup_mmu_ops(void) {}
+static inline void set_hv_tscchange_cb(void (*cb)(void)) {}
+static inline void clear_hv_tscchange_cb(void) {}
+static inline void hyperv_stop_tsc_emulation(void) {};
+static inline struct hv_vp_assist_page *hv_get_vp_assist_page(unsigned int cpu)
+{
+ return NULL;
+}
+static inline int hyperv_flush_guest_mapping(u64 as) { return -1; }
+#endif /* CONFIG_HYPERV */
+
+#ifdef CONFIG_HYPERV_TSCPAGE
+struct ms_hyperv_tsc_page *hv_get_tsc_page(void);
+static inline u64 hv_read_tsc_page_tsc(const struct ms_hyperv_tsc_page *tsc_pg,
+ u64 *cur_tsc)
+{
+ u64 scale, offset;
+ 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;
+}
+
+static inline u64 hv_read_tsc_page(const struct ms_hyperv_tsc_page *tsc_pg)
+{
+ u64 cur_tsc;
+
+ return hv_read_tsc_page_tsc(tsc_pg, &cur_tsc);
+}
+
+#else
+static inline struct ms_hyperv_tsc_page *hv_get_tsc_page(void)
+{
+ return NULL;
+}
+
+static inline u64 hv_read_tsc_page_tsc(const struct ms_hyperv_tsc_page *tsc_pg,
+ u64 *cur_tsc)
+{
+ BUG();
+ return U64_MAX;
+}
+#endif
+#endif