[mirror_ubuntu-artful-kernel.git] / arch / x86 / include / asm / mshyperv.h

#ifndef _ASM_X86_MSHYPER_H
#define _ASM_X86_MSHYPER_H

#include <linux/types.h>
#include <linux/atomic.h>
#include <asm/hyperv.h>

/*
 * The below CPUID leaves are present if VersionAndFeatures.HypervisorPresent
 * is set by CPUID(HVCPUID_VERSION_FEATURES).
 */
enum hv_cpuid_function {
	HVCPUID_VERSION_FEATURES		= 0x00000001,
	HVCPUID_VENDOR_MAXFUNCTION		= 0x40000000,
	HVCPUID_INTERFACE			= 0x40000001,

	/*
	 * The remaining functions depend on the value of
	 * HVCPUID_INTERFACE
	 */
	HVCPUID_VERSION				= 0x40000002,
	HVCPUID_FEATURES			= 0x40000003,
	HVCPUID_ENLIGHTENMENT_INFO		= 0x40000004,
	HVCPUID_IMPLEMENTATION_LIMITS		= 0x40000005,
};

struct ms_hyperv_info {
	u32 features;
	u32 misc_features;
	u32 hints;
};

extern struct ms_hyperv_info ms_hyperv;

/*
 * Declare the MSR used to setup pages used to communicate with the hypervisor.
 */
union hv_x64_msr_hypercall_contents {
	u64 as_uint64;
	struct {
		u64 enable:1;
		u64 reserved:11;
		u64 guest_physical_address:52;
	};
};

/*
 * TSC page layout.
 */

struct ms_hyperv_tsc_page {
	volatile u32 tsc_sequence;
	u32 reserved1;
	volatile u64 tsc_scale;
	volatile s64 tsc_offset;
	u64 reserved2[509];
};

/*
 * The guest OS needs to register the guest ID with the hypervisor.
 * The guest ID is a 64 bit entity and the structure of this ID is
 * specified in the Hyper-V specification:
 *
 * msdn.microsoft.com/en-us/library/windows/hardware/ff542653%28v=vs.85%29.aspx
 *
 * While the current guideline does not specify how Linux guest ID(s)
 * need to be generated, our plan is to publish the guidelines for
 * Linux and other guest operating systems that currently are hosted
 * on Hyper-V. The implementation here conforms to this yet
 * unpublished guidelines.
 *
 *
 * Bit(s)
 * 63 - Indicates if the OS is Open Source or not; 1 is Open Source
 * 62:56 - Os Type; Linux is 0x100
 * 55:48 - Distro specific identification
 * 47:16 - Linux kernel version number
 * 15:0  - Distro specific identification
 *
 *
 */

#define HV_LINUX_VENDOR_ID              0x8100

/*
 * Generate the guest ID based on the guideline described above.
 */

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(timer, tick)
#define hv_init_timer_config(config, val) wrmsrl(config, 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(int_num, val)
#define hv_set_synint_state(int_num, val) wrmsrl(int_num, val)

void hyperv_callback_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);

#if IS_ENABLED(CONFIG_HYPERV)
extern struct clocksource *hyperv_cs;

void hyperv_init(void);
void hyperv_report_panic(struct pt_regs *regs);
bool hv_is_hypercall_page_setup(void);
void hyperv_cleanup(void);
#endif
#ifdef CONFIG_HYPERV_TSCPAGE
struct ms_hyperv_tsc_page *hv_get_tsc_page(void);
static inline u64 hv_read_tsc_page(const struct ms_hyperv_tsc_page *tsc_pg)
{
	u64 scale, offset, cur_tsc;
	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;
}

#else
static inline struct ms_hyperv_tsc_page *hv_get_tsc_page(void)
{
	return NULL;
}
#endif
#endif
Commit	Line	Data
e08cae41 PA	1	#ifndef _ASM_X86_MSHYPER_H
e08cae41 PA	2	#define _ASM_X86_MSHYPER_H
a2a47c6c	3
e08cae41	4	#include <linux/types.h>
26fcd952	5	#include <linux/atomic.h>
e08cae41 PA	6	#include <asm/hyperv.h>
e08cae41 PA	7
8de8af7e S	8	/*
	9	* The below CPUID leaves are present if VersionAndFeatures.HypervisorPresent
	10	* is set by CPUID(HVCPUID_VERSION_FEATURES).
	11	*/
	12	enum hv_cpuid_function {
	13	HVCPUID_VERSION_FEATURES = 0x00000001,
	14	HVCPUID_VENDOR_MAXFUNCTION = 0x40000000,
	15	HVCPUID_INTERFACE = 0x40000001,
	16
	17	/*
	18	* The remaining functions depend on the value of
	19	* HVCPUID_INTERFACE
	20	*/
	21	HVCPUID_VERSION = 0x40000002,
	22	HVCPUID_FEATURES = 0x40000003,
	23	HVCPUID_ENLIGHTENMENT_INFO = 0x40000004,
	24	HVCPUID_IMPLEMENTATION_LIMITS = 0x40000005,
	25	};
	26
e08cae41 PA	27	struct ms_hyperv_info {
e08cae41 PA	28	u32 features;
cc2dd402	29	u32 misc_features;
e08cae41 PA	30	u32 hints;
	31	};
	32
	33	extern struct ms_hyperv_info ms_hyperv;
a2a47c6c	34
3f646ed7 S	35	/*
	36	* Declare the MSR used to setup pages used to communicate with the hypervisor.
	37	*/
	38	union hv_x64_msr_hypercall_contents {
	39	u64 as_uint64;
	40	struct {
	41	u64 enable:1;
	42	u64 reserved:11;
	43	u64 guest_physical_address:52;
	44	};
	45	};
	46
63ed4e0c S	47	/*
	48	* TSC page layout.
	49	*/
	50
	51	struct ms_hyperv_tsc_page {
	52	volatile u32 tsc_sequence;
	53	u32 reserved1;
	54	volatile u64 tsc_scale;
	55	volatile s64 tsc_offset;
	56	u64 reserved2[509];
	57	};
	58
352c9624 S	59	/*
	60	* The guest OS needs to register the guest ID with the hypervisor.
	61	* The guest ID is a 64 bit entity and the structure of this ID is
	62	* specified in the Hyper-V specification:
	63	*
	64	* msdn.microsoft.com/en-us/library/windows/hardware/ff542653%28v=vs.85%29.aspx
	65	*
	66	* While the current guideline does not specify how Linux guest ID(s)
	67	* need to be generated, our plan is to publish the guidelines for
	68	* Linux and other guest operating systems that currently are hosted
	69	* on Hyper-V. The implementation here conforms to this yet
	70	* unpublished guidelines.
	71	*
	72	*
	73	* Bit(s)
	74	* 63 - Indicates if the OS is Open Source or not; 1 is Open Source
	75	* 62:56 - Os Type; Linux is 0x100
	76	* 55:48 - Distro specific identification
	77	* 47:16 - Linux kernel version number
	78	* 15:0 - Distro specific identification
	79	*
	80	*
	81	*/
	82
9b06e101	83	#define HV_LINUX_VENDOR_ID 0x8100
352c9624 S	84
	85	/*
	86	* Generate the guest ID based on the guideline described above.
	87	*/
	88
	89	static inline __u64 generate_guest_id(__u64 d_info1, __u64 kernel_version,
	90	__u64 d_info2)
	91	{
	92	__u64 guest_id = 0;
	93
9b06e101	94	guest_id = (((__u64)HV_LINUX_VENDOR_ID) << 48);
352c9624 S	95	guest_id \|= (d_info1 << 48);
	96	guest_id \|= (kernel_version << 16);
	97	guest_id \|= d_info2;
	98
	99	return guest_id;
	100	}
	101
e810e48c S	102
	103	/* Free the message slot and signal end-of-message if required */
	104	static inline void vmbus_signal_eom(struct hv_message *msg, u32 old_msg_type)
	105	{
	106	/*
	107	* On crash we're reading some other CPU's message page and we need
	108	* to be careful: this other CPU may already had cleared the header
	109	* and the host may already had delivered some other message there.
	110	* In case we blindly write msg->header.message_type we're going
	111	* to lose it. We can still lose a message of the same type but
	112	* we count on the fact that there can only be one
	113	* CHANNELMSG_UNLOAD_RESPONSE and we don't care about other messages
	114	* on crash.
	115	*/
	116	if (cmpxchg(&msg->header.message_type, old_msg_type,
	117	HVMSG_NONE) != old_msg_type)
	118	return;
	119
	120	/*
	121	* Make sure the write to MessageType (ie set to
	122	* HVMSG_NONE) happens before we read the
	123	* MessagePending and EOMing. Otherwise, the EOMing
	124	* will not deliver any more messages since there is
	125	* no empty slot
	126	*/
	127	mb();
	128
	129	if (msg->header.message_flags.msg_pending) {
	130	/*
	131	* This will cause message queue rescan to
	132	* possibly deliver another msg from the
	133	* hypervisor
	134	*/
	135	wrmsrl(HV_X64_MSR_EOM, 0);
	136	}
	137	}
	138
d5116b40 S	139	#define hv_init_timer(timer, tick) wrmsrl(timer, tick)
	140	#define hv_init_timer_config(config, val) wrmsrl(config, val)
	141
155e4a2f S	142	#define hv_get_simp(val) rdmsrl(HV_X64_MSR_SIMP, val)
	143	#define hv_set_simp(val) wrmsrl(HV_X64_MSR_SIMP, val)
	144
8e307bf8 S	145	#define hv_get_siefp(val) rdmsrl(HV_X64_MSR_SIEFP, val)
	146	#define hv_set_siefp(val) wrmsrl(HV_X64_MSR_SIEFP, val)
	147
06d1d98a S	148	#define hv_get_synic_state(val) rdmsrl(HV_X64_MSR_SCONTROL, val)
	149	#define hv_set_synic_state(val) wrmsrl(HV_X64_MSR_SCONTROL, val)
	150
7297ff0c S	151	#define hv_get_vp_index(index) rdmsrl(HV_X64_MSR_VP_INDEX, index)
7297ff0c S	152
37e11d5c S	153	#define hv_get_synint_state(int_num, val) rdmsrl(int_num, val)
	154	#define hv_set_synint_state(int_num, val) wrmsrl(int_num, val)
	155
bc2b0331	156	void hyperv_callback_vector(void);
cf910e83 SA	157	#ifdef CONFIG_TRACING
	158	#define trace_hyperv_callback_vector hyperv_callback_vector
	159	#endif
bc2b0331	160	void hyperv_vector_handler(struct pt_regs *regs);
76d388cd TG	161	void hv_setup_vmbus_irq(void (*handler)(void));
76d388cd TG	162	void hv_remove_vmbus_irq(void);
bc2b0331	163
2517281d VK	164	void hv_setup_kexec_handler(void (*handler)(void));
2517281d VK	165	void hv_remove_kexec_handler(void);
b4370df2 VK	166	void hv_setup_crash_handler(void (handler)(struct pt_regs regs));
b4370df2 VK	167	void hv_remove_crash_handler(void);
8730046c S	168
8730046c S	169	#if IS_ENABLED(CONFIG_HYPERV)
dee863b5 VK	170	extern struct clocksource *hyperv_cs;
dee863b5 VK	171
8730046c	172	void hyperv_init(void);
d058fa7e	173	void hyperv_report_panic(struct pt_regs *regs);
73638cdd	174	bool hv_is_hypercall_page_setup(void);
d6f3609d	175	void hyperv_cleanup(void);
8730046c	176	#endif
bd2a9ada VK	177	#ifdef CONFIG_HYPERV_TSCPAGE
bd2a9ada VK	178	struct ms_hyperv_tsc_page *hv_get_tsc_page(void);
0733379b VK	179	static inline u64 hv_read_tsc_page(const struct ms_hyperv_tsc_page *tsc_pg)
	180	{
	181	u64 scale, offset, cur_tsc;
	182	u32 sequence;
	183
	184	/*
	185	* The protocol for reading Hyper-V TSC page is specified in Hypervisor
	186	* Top-Level Functional Specification ver. 3.0 and above. To get the
	187	* reference time we must do the following:
	188	* - READ ReferenceTscSequence
	189	* A special '0' value indicates the time source is unreliable and we
	190	* need to use something else. The currently published specification
	191	* versions (up to 4.0b) contain a mistake and wrongly claim '-1'
	192	* instead of '0' as the special value, see commit c35b82ef0294.
	193	* - ReferenceTime =
	194	* ((RDTSC() * ReferenceTscScale) >> 64) + ReferenceTscOffset
	195	* - READ ReferenceTscSequence again. In case its value has changed
	196	* since our first reading we need to discard ReferenceTime and repeat
	197	* the whole sequence as the hypervisor was updating the page in
	198	* between.
	199	*/
	200	do {
	201	sequence = READ_ONCE(tsc_pg->tsc_sequence);
	202	if (!sequence)
	203	return U64_MAX;
	204	/*
	205	* Make sure we read sequence before we read other values from
	206	* TSC page.
	207	*/
	208	smp_rmb();
	209
	210	scale = READ_ONCE(tsc_pg->tsc_scale);
	211	offset = READ_ONCE(tsc_pg->tsc_offset);
	212	cur_tsc = rdtsc_ordered();
	213
	214	/*
	215	* Make sure we read sequence after we read all other values
	216	* from TSC page.
	217	*/
	218	smp_rmb();
	219
	220	} while (READ_ONCE(tsc_pg->tsc_sequence) != sequence);
	221
	222	return mul_u64_u64_shr(cur_tsc, scale, 64) + offset;
	223	}
	224
bd2a9ada VK	225	#else
	226	static inline struct ms_hyperv_tsc_page *hv_get_tsc_page(void)
	227	{
	228	return NULL;
	229	}
	230	#endif
a2a47c6c	231	#endif