[linux-2.6-block.git] / include / asm-generic / mshyperv.h

/* 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 <linux/nmi.h>
#include <asm/ptrace.h>
#include <asm/hyperv-tlfs.h>

struct ms_hyperv_info {
	u32 features;
	u32 priv_high;
	u32 misc_features;
	u32 hints;
	u32 nested_features;
	u32 max_vp_index;
	u32 max_lp_index;
	u32 isolation_config_a;
	union {
		u32 isolation_config_b;
		struct {
			u32 cvm_type : 4;
			u32 reserved1 : 1;
			u32 shared_gpa_boundary_active : 1;
			u32 shared_gpa_boundary_bits : 6;
			u32 reserved2 : 20;
		};
	};
	u64 shared_gpa_boundary;
};
extern struct ms_hyperv_info ms_hyperv;

extern void * __percpu *hyperv_pcpu_input_arg;
extern void * __percpu *hyperv_pcpu_output_arg;

extern u64 hv_do_hypercall(u64 control, void *inputaddr, void *outputaddr);
extern u64 hv_do_fast_hypercall8(u16 control, u64 input8);
extern bool hv_isolation_type_snp(void);

/* Helper functions that provide a consistent pattern for checking Hyper-V hypercall status. */
static inline int hv_result(u64 status)
{
	return status & HV_HYPERCALL_RESULT_MASK;
}

static inline bool hv_result_success(u64 status)
{
	return hv_result(status) == HV_STATUS_SUCCESS;
}

static inline unsigned int hv_repcomp(u64 status)
{
	/* Bits [43:32] of status have 'Reps completed' data. */
	return (status & HV_HYPERCALL_REP_COMP_MASK) >>
			 HV_HYPERCALL_REP_COMP_OFFSET;
}

/*
 * 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 (!hv_result_success(status))
			return status;

		rep_comp = hv_repcomp(status);

		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;
}

/* 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_set_register(HV_REGISTER_EOM, 0);
	}
}

void hv_setup_vmbus_handler(void (*handler)(void));
void hv_remove_vmbus_handler(void);
void hv_setup_stimer0_handler(void (*handler)(void));
void hv_remove_stimer0_handler(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);

extern int vmbus_interrupt;
extern int vmbus_irq;

extern bool hv_root_partition;

#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;

extern u64 (*hv_read_reference_counter)(void);

/* Sentinel value for an uninitialized entry in hv_vp_index array */
#define VP_INVAL	U32_MAX

int __init hv_common_init(void);
void __init hv_common_free(void);
int hv_common_cpu_init(unsigned int cpu);
int hv_common_cpu_die(unsigned int cpu);

void *hv_alloc_hyperv_page(void);
void *hv_alloc_hyperv_zeroed_page(void);
void hv_free_hyperv_page(unsigned long addr);

/**
 * 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,
				    bool exclude_self)
{
	int cpu, vcpu, vcpu_bank, vcpu_offset, nr_bank = 1;
	int this_cpu = smp_processor_id();

	/* 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) {
		if (exclude_self && cpu == this_cpu)
			continue;
		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;
}

static inline int cpumask_to_vpset(struct hv_vpset *vpset,
				    const struct cpumask *cpus)
{
	return __cpumask_to_vpset(vpset, cpus, false);
}

static inline int cpumask_to_vpset_noself(struct hv_vpset *vpset,
				    const struct cpumask *cpus)
{
	WARN_ON_ONCE(preemptible());
	return __cpumask_to_vpset(vpset, cpus, true);
}

void hyperv_report_panic(struct pt_regs *regs, long err, bool in_die);
bool hv_is_hyperv_initialized(void);
bool hv_is_hibernation_supported(void);
enum hv_isolation_type hv_get_isolation_type(void);
bool hv_is_isolation_supported(void);
bool hv_isolation_type_snp(void);
u64 hv_ghcb_hypercall(u64 control, void *input, void *output, u32 input_size);
void hyperv_cleanup(void);
bool hv_query_ext_cap(u64 cap_query);
void hv_setup_dma_ops(struct device *dev, bool coherent);
void *hv_map_memory(void *addr, unsigned long size);
void hv_unmap_memory(void *addr);
#else /* CONFIG_HYPERV */
static inline bool hv_is_hyperv_initialized(void) { return false; }
static inline bool hv_is_hibernation_supported(void) { return false; }
static inline void hyperv_cleanup(void) {}
static inline bool hv_is_isolation_supported(void) { return false; }
static inline enum hv_isolation_type hv_get_isolation_type(void)
{
	return HV_ISOLATION_TYPE_NONE;
}
#endif /* CONFIG_HYPERV */

#endif
Commit	Line	Data
765e33f5 MK	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 <linux/cpumask.h>
ba3f5839	25	#include <linux/nmi.h>
765e33f5 MK	26	#include <asm/ptrace.h>
	27	#include <asm/hyperv-tlfs.h>
	28
	29	struct ms_hyperv_info {
	30	u32 features;
6dc2a774	31	u32 priv_high;
765e33f5 MK	32	u32 misc_features;
	33	u32 hints;
	34	u32 nested_features;
	35	u32 max_vp_index;
	36	u32 max_lp_index;
a6c76bb0	37	u32 isolation_config_a;
af788f35 TL	38	union {
	39	u32 isolation_config_b;
	40	struct {
	41	u32 cvm_type : 4;
	42	u32 reserved1 : 1;
	43	u32 shared_gpa_boundary_active : 1;
	44	u32 shared_gpa_boundary_bits : 6;
	45	u32 reserved2 : 20;
	46	};
	47	};
	48	u64 shared_gpa_boundary;
765e33f5 MK	49	};
	50	extern struct ms_hyperv_info ms_hyperv;
	51
db3c65bc MK	52	extern void * __percpu *hyperv_pcpu_input_arg;
db3c65bc MK	53	extern void * __percpu *hyperv_pcpu_output_arg;
afca4d95	54
765e33f5 MK	55	extern u64 hv_do_hypercall(u64 control, void inputaddr, void outputaddr);
765e33f5 MK	56	extern u64 hv_do_fast_hypercall8(u16 control, u64 input8);
faff4406	57	extern bool hv_isolation_type_snp(void);
765e33f5	58
753ed9c9 JS	59	/* Helper functions that provide a consistent pattern for checking Hyper-V hypercall status. */
	60	static inline int hv_result(u64 status)
	61	{
	62	return status & HV_HYPERCALL_RESULT_MASK;
	63	}
	64
	65	static inline bool hv_result_success(u64 status)
	66	{
	67	return hv_result(status) == HV_STATUS_SUCCESS;
	68	}
	69
	70	static inline unsigned int hv_repcomp(u64 status)
	71	{
	72	/* Bits [43:32] of status have 'Reps completed' data. */
	73	return (status & HV_HYPERCALL_REP_COMP_MASK) >>
	74	HV_HYPERCALL_REP_COMP_OFFSET;
	75	}
	76
6523592c JS	77	/*
	78	* Rep hypercalls. Callers of this functions are supposed to ensure that
	79	* rep_count and varhead_size comply with Hyper-V hypercall definition.
	80	*/
	81	static inline u64 hv_do_rep_hypercall(u16 code, u16 rep_count, u16 varhead_size,
	82	void input, void output)
	83	{
	84	u64 control = code;
	85	u64 status;
	86	u16 rep_comp;
	87
	88	control \|= (u64)varhead_size << HV_HYPERCALL_VARHEAD_OFFSET;
	89	control \|= (u64)rep_count << HV_HYPERCALL_REP_COMP_OFFSET;
	90
	91	do {
	92	status = hv_do_hypercall(control, input, output);
753ed9c9	93	if (!hv_result_success(status))
6523592c JS	94	return status;
6523592c JS	95
753ed9c9	96	rep_comp = hv_repcomp(status);
6523592c JS	97
	98	control &= ~HV_HYPERCALL_REP_START_MASK;
	99	control \|= (u64)rep_comp << HV_HYPERCALL_REP_START_OFFSET;
	100
	101	touch_nmi_watchdog();
	102	} while (rep_comp < rep_count);
	103
	104	return status;
	105	}
765e33f5 MK	106
	107	/* Generate the guest OS identifier as described in the Hyper-V TLFS */
	108	static inline __u64 generate_guest_id(__u64 d_info1, __u64 kernel_version,
	109	__u64 d_info2)
	110	{
	111	__u64 guest_id = 0;
	112
	113	guest_id = (((__u64)HV_LINUX_VENDOR_ID) << 48);
	114	guest_id \|= (d_info1 << 48);
	115	guest_id \|= (kernel_version << 16);
	116	guest_id \|= d_info2;
	117
	118	return guest_id;
	119	}
	120
765e33f5 MK	121	/* Free the message slot and signal end-of-message if required */
	122	static inline void vmbus_signal_eom(struct hv_message *msg, u32 old_msg_type)
	123	{
	124	/*
	125	* On crash we're reading some other CPU's message page and we need
	126	* to be careful: this other CPU may already had cleared the header
	127	* and the host may already had delivered some other message there.
	128	* In case we blindly write msg->header.message_type we're going
	129	* to lose it. We can still lose a message of the same type but
	130	* we count on the fact that there can only be one
	131	* CHANNELMSG_UNLOAD_RESPONSE and we don't care about other messages
	132	* on crash.
	133	*/
	134	if (cmpxchg(&msg->header.message_type, old_msg_type,
	135	HVMSG_NONE) != old_msg_type)
	136	return;
	137
	138	/*
	139	* The cmxchg() above does an implicit memory barrier to
	140	* ensure the write to MessageType (ie set to
	141	* HVMSG_NONE) happens before we read the
	142	* MessagePending and EOMing. Otherwise, the EOMing
	143	* will not deliver any more messages since there is
	144	* no empty slot
	145	*/
	146	if (msg->header.message_flags.msg_pending) {
	147	/*
	148	* This will cause message queue rescan to
	149	* possibly deliver another msg from the
	150	* hypervisor
	151	*/
f3c5e63c	152	hv_set_register(HV_REGISTER_EOM, 0);
765e33f5 MK	153	}
	154	}
	155
d608715d MK	156	void hv_setup_vmbus_handler(void (*handler)(void));
d608715d MK	157	void hv_remove_vmbus_handler(void);
a620bbaa MK	158	void hv_setup_stimer0_handler(void (*handler)(void));
a620bbaa MK	159	void hv_remove_stimer0_handler(void);
765e33f5 MK	160
	161	void hv_setup_kexec_handler(void (*handler)(void));
	162	void hv_remove_kexec_handler(void);
	163	void hv_setup_crash_handler(void (handler)(struct pt_regs regs));
	164	void hv_remove_crash_handler(void);
	165
626b901f	166	extern int vmbus_interrupt;
d608715d	167	extern int vmbus_irq;
626b901f	168
afca4d95 MK	169	extern bool hv_root_partition;
afca4d95 MK	170
765e33f5 MK	171	#if IS_ENABLED(CONFIG_HYPERV)
	172	/*
	173	* Hypervisor's notion of virtual processor ID is different from
	174	* Linux' notion of CPU ID. This information can only be retrieved
	175	* in the context of the calling CPU. Setup a map for easy access
	176	* to this information.
	177	*/
	178	extern u32 *hv_vp_index;
	179	extern u32 hv_max_vp_index;
	180
31e5e646 MK	181	extern u64 (*hv_read_reference_counter)(void);
31e5e646 MK	182
765e33f5 MK	183	/* Sentinel value for an uninitialized entry in hv_vp_index array */
	184	#define VP_INVAL U32_MAX
	185
afca4d95 MK	186	int __init hv_common_init(void);
	187	void __init hv_common_free(void);
	188	int hv_common_cpu_init(unsigned int cpu);
	189	int hv_common_cpu_die(unsigned int cpu);
	190
ca48739e MK	191	void *hv_alloc_hyperv_page(void);
	192	void *hv_alloc_hyperv_zeroed_page(void);
	193	void hv_free_hyperv_page(unsigned long addr);
	194
765e33f5 MK	195	/**
	196	* hv_cpu_number_to_vp_number() - Map CPU to VP.
	197	* @cpu_number: CPU number in Linux terms
	198	*
	199	* This function returns the mapping between the Linux processor
	200	* number and the hypervisor's virtual processor number, useful
	201	* in making hypercalls and such that talk about specific
	202	* processors.
	203	*
	204	* Return: Virtual processor number in Hyper-V terms
	205	*/
	206	static inline int hv_cpu_number_to_vp_number(int cpu_number)
	207	{
	208	return hv_vp_index[cpu_number];
	209	}
	210
7ad9bb9d WL	211	static inline int __cpumask_to_vpset(struct hv_vpset *vpset,
	212	const struct cpumask *cpus,
	213	bool exclude_self)
765e33f5 MK	214	{
765e33f5 MK	215	int cpu, vcpu, vcpu_bank, vcpu_offset, nr_bank = 1;
7ad9bb9d	216	int this_cpu = smp_processor_id();
765e33f5 MK	217
	218	/* valid_bank_mask can represent up to 64 banks */
	219	if (hv_max_vp_index / 64 >= 64)
	220	return 0;
	221
	222	/*
	223	* Clear all banks up to the maximum possible bank as hv_tlb_flush_ex
	224	* structs are not cleared between calls, we risk flushing unneeded
	225	* vCPUs otherwise.
	226	*/
	227	for (vcpu_bank = 0; vcpu_bank <= hv_max_vp_index / 64; vcpu_bank++)
	228	vpset->bank_contents[vcpu_bank] = 0;
	229
	230	/*
	231	* Some banks may end up being empty but this is acceptable.
	232	*/
	233	for_each_cpu(cpu, cpus) {
7ad9bb9d WL	234	if (exclude_self && cpu == this_cpu)
7ad9bb9d WL	235	continue;
765e33f5 MK	236	vcpu = hv_cpu_number_to_vp_number(cpu);
	237	if (vcpu == VP_INVAL)
	238	return -1;
	239	vcpu_bank = vcpu / 64;
	240	vcpu_offset = vcpu % 64;
	241	__set_bit(vcpu_offset, (unsigned long *)
	242	&vpset->bank_contents[vcpu_bank]);
	243	if (vcpu_bank >= nr_bank)
	244	nr_bank = vcpu_bank + 1;
	245	}
	246	vpset->valid_bank_mask = GENMASK_ULL(nr_bank - 1, 0);
	247	return nr_bank;
	248	}
	249
7ad9bb9d WL	250	static inline int cpumask_to_vpset(struct hv_vpset *vpset,
	251	const struct cpumask *cpus)
	252	{
	253	return __cpumask_to_vpset(vpset, cpus, false);
	254	}
	255
	256	static inline int cpumask_to_vpset_noself(struct hv_vpset *vpset,
	257	const struct cpumask *cpus)
	258	{
	259	WARN_ON_ONCE(preemptible());
	260	return __cpumask_to_vpset(vpset, cpus, true);
	261	}
	262
f3a99e76	263	void hyperv_report_panic(struct pt_regs *regs, long err, bool in_die);
765e33f5	264	bool hv_is_hyperv_initialized(void);
b96f8653	265	bool hv_is_hibernation_supported(void);
a6c76bb0 APM	266	enum hv_isolation_type hv_get_isolation_type(void);
a6c76bb0 APM	267	bool hv_is_isolation_supported(void);
0cc4f6d9	268	bool hv_isolation_type_snp(void);
20c89a55	269	u64 hv_ghcb_hypercall(u64 control, void input, void output, u32 input_size);
765e33f5	270	void hyperv_cleanup(void);
6dc2a774	271	bool hv_query_ext_cap(u64 cap_query);
37200078	272	void hv_setup_dma_ops(struct device *dev, bool coherent);
846da38d TL	273	void hv_map_memory(void addr, unsigned long size);
846da38d TL	274	void hv_unmap_memory(void *addr);
765e33f5 MK	275	#else /* CONFIG_HYPERV */
765e33f5 MK	276	static inline bool hv_is_hyperv_initialized(void) { return false; }
b96f8653	277	static inline bool hv_is_hibernation_supported(void) { return false; }
765e33f5	278	static inline void hyperv_cleanup(void) {}
0cc4f6d9 TL	279	static inline bool hv_is_isolation_supported(void) { return false; }
	280	static inline enum hv_isolation_type hv_get_isolation_type(void)
	281	{
	282	return HV_ISOLATION_TYPE_NONE;
	283	}
765e33f5 MK	284	#endif /* CONFIG_HYPERV */
765e33f5 MK	285
765e33f5	286	#endif