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Diffstat (limited to 'include/asm-generic/mshyperv.h')
| -rw-r--r-- | include/asm-generic/mshyperv.h | 180 |
1 files changed, 180 insertions, 0 deletions
diff --git a/include/asm-generic/mshyperv.h b/include/asm-generic/mshyperv.h new file mode 100644 index 000000000000..0becb7d9704d --- /dev/null +++ b/include/asm-generic/mshyperv.h @@ -0,0 +1,180 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +/* + * Linux-specific definitions for managing interactions with Microsoft's + * Hyper-V hypervisor. The definitions in this file are architecture + * independent. See arch/<arch>/include/asm/mshyperv.h for definitions + * that are specific to architecture <arch>. + * + * Definitions that are specified in the Hyper-V Top Level Functional + * Spec (TLFS) should not go in this file, but should instead go in + * hyperv-tlfs.h. + * + * Copyright (C) 2019, Microsoft, Inc. + * + * Author : Michael Kelley <mikelley@microsoft.com> + */ + +#ifndef _ASM_GENERIC_MSHYPERV_H +#define _ASM_GENERIC_MSHYPERV_H + +#include <linux/types.h> +#include <linux/atomic.h> +#include <linux/bitops.h> +#include <linux/cpumask.h> +#include <asm/ptrace.h> +#include <asm/hyperv-tlfs.h> + +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; + +extern u64 hv_do_hypercall(u64 control, void *inputaddr, void *outputaddr); +extern u64 hv_do_fast_hypercall8(u16 control, u64 input8); + + +/* Generate the guest OS identifier as described in the Hyper-V TLFS */ +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; + + /* + * The cmxchg() above does an implicit memory barrier to + * ensure 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 + */ + if (msg->header.message_flags.msg_pending) { + /* + * This will cause message queue rescan to + * possibly deliver another msg from the + * hypervisor + */ + hv_signal_eom(); + } +} + +void hv_setup_vmbus_irq(void (*handler)(void)); +void hv_remove_vmbus_irq(void); +void hv_enable_vmbus_irq(void); +void hv_disable_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) +/* + * 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; + +/* Sentinel value for an uninitialized entry in hv_vp_index array */ +#define VP_INVAL U32_MAX + +/** + * 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 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); +#else /* CONFIG_HYPERV */ +static inline bool hv_is_hyperv_initialized(void) { return false; } +static inline void hyperv_cleanup(void) {} +#endif /* CONFIG_HYPERV */ + +#if IS_ENABLED(CONFIG_HYPERV) +extern int hv_setup_stimer0_irq(int *irq, int *vector, void (*handler)(void)); +extern void hv_remove_stimer0_irq(int irq); +#endif + +#endif |