[PATCH v2 03/10] Drivers: hv: Redo Hyper-V synthetic MSR get/set functions

From: Michael Kelley
Date: Sun Feb 28 2021 - 20:18:54 EST


Current code defines a separate get and set macro for each Hyper-V
synthetic MSR used by the VMbus driver. Furthermore, the get macro
can't be converted to a standard function because the second argument
is modified in place, which is somewhat bad form.

Redo this by providing a single get and a single set function that
take a parameter specifying the MSR to be operated on. Fixup usage
of the get function. Calling locations are no more complex than before,
but the code under arch/x86 and the upcoming code under arch/arm64
is significantly simplified.

Also standardize the names of Hyper-V synthetic MSRs that are
architecture neutral. But keep the old x86-specific names as aliases
that can be removed later when all references (particularly in KVM
code) have been cleaned up in a separate patch series.

No functional change.

Signed-off-by: Michael Kelley <mikelley@xxxxxxxxxxxxx>
Reviewed-by: Boqun Feng <boqun.feng@xxxxxxxxx>
---
arch/x86/hyperv/hv_init.c | 2 +-
arch/x86/include/asm/hyperv-tlfs.h | 102 +++++++++++++++++++++++--------------
arch/x86/include/asm/mshyperv.h | 39 ++++----------
drivers/clocksource/hyperv_timer.c | 26 +++++-----
drivers/hv/hv.c | 37 ++++++++------
drivers/hv/vmbus_drv.c | 2 +-
include/asm-generic/mshyperv.h | 2 +-
7 files changed, 110 insertions(+), 100 deletions(-)

diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c
index 4bdb344..94d52c5 100644
--- a/arch/x86/hyperv/hv_init.c
+++ b/arch/x86/hyperv/hv_init.c
@@ -75,7 +75,7 @@ static int hv_cpu_init(unsigned int cpu)
*output_arg = page_address(pg + 1);
}

- hv_get_vp_index(msr_vp_index);
+ msr_vp_index = hv_get_register(HV_REGISTER_VP_INDEX);

hv_vp_index[smp_processor_id()] = msr_vp_index;

diff --git a/arch/x86/include/asm/hyperv-tlfs.h b/arch/x86/include/asm/hyperv-tlfs.h
index 68b38a2..606f5cc 100644
--- a/arch/x86/include/asm/hyperv-tlfs.h
+++ b/arch/x86/include/asm/hyperv-tlfs.h
@@ -156,7 +156,7 @@ enum hv_isolation_type {
#define HV_X64_MSR_HYPERCALL 0x40000001

/* MSR used to provide vcpu index */
-#define HV_X64_MSR_VP_INDEX 0x40000002
+#define HV_REGISTER_VP_INDEX 0x40000002

/* MSR used to reset the guest OS. */
#define HV_X64_MSR_RESET 0x40000003
@@ -165,10 +165,10 @@ enum hv_isolation_type {
#define HV_X64_MSR_VP_RUNTIME 0x40000010

/* MSR used to read the per-partition time reference counter */
-#define HV_X64_MSR_TIME_REF_COUNT 0x40000020
+#define HV_REGISTER_TIME_REF_COUNT 0x40000020

/* A partition's reference time stamp counter (TSC) page */
-#define HV_X64_MSR_REFERENCE_TSC 0x40000021
+#define HV_REGISTER_REFERENCE_TSC 0x40000021

/* MSR used to retrieve the TSC frequency */
#define HV_X64_MSR_TSC_FREQUENCY 0x40000022
@@ -183,50 +183,50 @@ enum hv_isolation_type {
#define HV_X64_MSR_VP_ASSIST_PAGE 0x40000073

/* Define synthetic interrupt controller model specific registers. */
-#define HV_X64_MSR_SCONTROL 0x40000080
-#define HV_X64_MSR_SVERSION 0x40000081
-#define HV_X64_MSR_SIEFP 0x40000082
-#define HV_X64_MSR_SIMP 0x40000083
-#define HV_X64_MSR_EOM 0x40000084
-#define HV_X64_MSR_SINT0 0x40000090
-#define HV_X64_MSR_SINT1 0x40000091
-#define HV_X64_MSR_SINT2 0x40000092
-#define HV_X64_MSR_SINT3 0x40000093
-#define HV_X64_MSR_SINT4 0x40000094
-#define HV_X64_MSR_SINT5 0x40000095
-#define HV_X64_MSR_SINT6 0x40000096
-#define HV_X64_MSR_SINT7 0x40000097
-#define HV_X64_MSR_SINT8 0x40000098
-#define HV_X64_MSR_SINT9 0x40000099
-#define HV_X64_MSR_SINT10 0x4000009A
-#define HV_X64_MSR_SINT11 0x4000009B
-#define HV_X64_MSR_SINT12 0x4000009C
-#define HV_X64_MSR_SINT13 0x4000009D
-#define HV_X64_MSR_SINT14 0x4000009E
-#define HV_X64_MSR_SINT15 0x4000009F
+#define HV_REGISTER_SCONTROL 0x40000080
+#define HV_REGISTER_SVERSION 0x40000081
+#define HV_REGISTER_SIEFP 0x40000082
+#define HV_REGISTER_SIMP 0x40000083
+#define HV_REGISTER_EOM 0x40000084
+#define HV_REGISTER_SINT0 0x40000090
+#define HV_REGISTER_SINT1 0x40000091
+#define HV_REGISTER_SINT2 0x40000092
+#define HV_REGISTER_SINT3 0x40000093
+#define HV_REGISTER_SINT4 0x40000094
+#define HV_REGISTER_SINT5 0x40000095
+#define HV_REGISTER_SINT6 0x40000096
+#define HV_REGISTER_SINT7 0x40000097
+#define HV_REGISTER_SINT8 0x40000098
+#define HV_REGISTER_SINT9 0x40000099
+#define HV_REGISTER_SINT10 0x4000009A
+#define HV_REGISTER_SINT11 0x4000009B
+#define HV_REGISTER_SINT12 0x4000009C
+#define HV_REGISTER_SINT13 0x4000009D
+#define HV_REGISTER_SINT14 0x4000009E
+#define HV_REGISTER_SINT15 0x4000009F

/*
* Synthetic Timer MSRs. Four timers per vcpu.
*/
-#define HV_X64_MSR_STIMER0_CONFIG 0x400000B0
-#define HV_X64_MSR_STIMER0_COUNT 0x400000B1
-#define HV_X64_MSR_STIMER1_CONFIG 0x400000B2
-#define HV_X64_MSR_STIMER1_COUNT 0x400000B3
-#define HV_X64_MSR_STIMER2_CONFIG 0x400000B4
-#define HV_X64_MSR_STIMER2_COUNT 0x400000B5
-#define HV_X64_MSR_STIMER3_CONFIG 0x400000B6
-#define HV_X64_MSR_STIMER3_COUNT 0x400000B7
+#define HV_REGISTER_STIMER0_CONFIG 0x400000B0
+#define HV_REGISTER_STIMER0_COUNT 0x400000B1
+#define HV_REGISTER_STIMER1_CONFIG 0x400000B2
+#define HV_REGISTER_STIMER1_COUNT 0x400000B3
+#define HV_REGISTER_STIMER2_CONFIG 0x400000B4
+#define HV_REGISTER_STIMER2_COUNT 0x400000B5
+#define HV_REGISTER_STIMER3_CONFIG 0x400000B6
+#define HV_REGISTER_STIMER3_COUNT 0x400000B7

/* Hyper-V guest idle MSR */
#define HV_X64_MSR_GUEST_IDLE 0x400000F0

/* Hyper-V guest crash notification MSR's */
-#define HV_X64_MSR_CRASH_P0 0x40000100
-#define HV_X64_MSR_CRASH_P1 0x40000101
-#define HV_X64_MSR_CRASH_P2 0x40000102
-#define HV_X64_MSR_CRASH_P3 0x40000103
-#define HV_X64_MSR_CRASH_P4 0x40000104
-#define HV_X64_MSR_CRASH_CTL 0x40000105
+#define HV_REGISTER_CRASH_P0 0x40000100
+#define HV_REGISTER_CRASH_P1 0x40000101
+#define HV_REGISTER_CRASH_P2 0x40000102
+#define HV_REGISTER_CRASH_P3 0x40000103
+#define HV_REGISTER_CRASH_P4 0x40000104
+#define HV_REGISTER_CRASH_CTL 0x40000105

/* TSC emulation after migration */
#define HV_X64_MSR_REENLIGHTENMENT_CONTROL 0x40000106
@@ -236,6 +236,32 @@ enum hv_isolation_type {
/* TSC invariant control */
#define HV_X64_MSR_TSC_INVARIANT_CONTROL 0x40000118

+/* Register name aliases for temporary compatibility */
+#define HV_X64_MSR_STIMER0_COUNT HV_REGISTER_STIMER0_COUNT
+#define HV_X64_MSR_STIMER0_CONFIG HV_REGISTER_STIMER0_CONFIG
+#define HV_X64_MSR_STIMER1_COUNT HV_REGISTER_STIMER1_COUNT
+#define HV_X64_MSR_STIMER1_CONFIG HV_REGISTER_STIMER1_CONFIG
+#define HV_X64_MSR_STIMER2_COUNT HV_REGISTER_STIMER2_COUNT
+#define HV_X64_MSR_STIMER2_CONFIG HV_REGISTER_STIMER2_CONFIG
+#define HV_X64_MSR_STIMER3_COUNT HV_REGISTER_STIMER3_COUNT
+#define HV_X64_MSR_STIMER3_CONFIG HV_REGISTER_STIMER3_CONFIG
+#define HV_X64_MSR_SCONTROL HV_REGISTER_SCONTROL
+#define HV_X64_MSR_SVERSION HV_REGISTER_SVERSION
+#define HV_X64_MSR_SIMP HV_REGISTER_SIMP
+#define HV_X64_MSR_SIEFP HV_REGISTER_SIEFP
+#define HV_X64_MSR_VP_INDEX HV_REGISTER_VP_INDEX
+#define HV_X64_MSR_EOM HV_REGISTER_EOM
+#define HV_X64_MSR_SINT0 HV_REGISTER_SINT0
+#define HV_X64_MSR_SINT15 HV_REGISTER_SINT15
+#define HV_X64_MSR_CRASH_P0 HV_REGISTER_CRASH_P0
+#define HV_X64_MSR_CRASH_P1 HV_REGISTER_CRASH_P1
+#define HV_X64_MSR_CRASH_P2 HV_REGISTER_CRASH_P2
+#define HV_X64_MSR_CRASH_P3 HV_REGISTER_CRASH_P3
+#define HV_X64_MSR_CRASH_P4 HV_REGISTER_CRASH_P4
+#define HV_X64_MSR_CRASH_CTL HV_REGISTER_CRASH_CTL
+#define HV_X64_MSR_TIME_REF_COUNT HV_REGISTER_TIME_REF_COUNT
+#define HV_X64_MSR_REFERENCE_TSC HV_REGISTER_REFERENCE_TSC
+
/*
* Declare the MSR used to setup pages used to communicate with the hypervisor.
*/
diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyperv.h
index ef6e968..2590ce5 100644
--- a/arch/x86/include/asm/mshyperv.h
+++ b/arch/x86/include/asm/mshyperv.h
@@ -14,41 +14,22 @@ typedef int (*hyperv_fill_flush_list_func)(
struct hv_guest_mapping_flush_list *flush,
void *data);

-#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)
+static inline void hv_set_register(unsigned int reg, u64 value)
+{
+ wrmsrl(reg, value);
+}

-#define hv_get_vp_index(index) rdmsrl(HV_X64_MSR_VP_INDEX, index)
+static inline u64 hv_get_register(unsigned int reg)
+{
+ u64 value;

-#define hv_signal_eom() wrmsrl(HV_X64_MSR_EOM, 0)
+ rdmsrl(reg, value);
+ return value;
+}

-#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_recommend_using_aeoi() \
(!(ms_hyperv.hints & HV_DEPRECATING_AEOI_RECOMMENDED))

-#define hv_get_crash_ctl(val) \
- rdmsrl(HV_X64_MSR_CRASH_CTL, val)
-
-#define hv_get_time_ref_count(val) \
- rdmsrl(HV_X64_MSR_TIME_REF_COUNT, val)
-
-#define hv_get_reference_tsc(val) \
- rdmsrl(HV_X64_MSR_REFERENCE_TSC, val)
-#define hv_set_reference_tsc(val) \
- wrmsrl(HV_X64_MSR_REFERENCE_TSC, val)
#define hv_set_clocksource_vdso(val) \
((val).vdso_clock_mode = VDSO_CLOCKMODE_HVCLOCK)
#define hv_enable_vdso_clocksource() \
diff --git a/drivers/clocksource/hyperv_timer.c b/drivers/clocksource/hyperv_timer.c
index 269a691..c73c127 100644
--- a/drivers/clocksource/hyperv_timer.c
+++ b/drivers/clocksource/hyperv_timer.c
@@ -68,14 +68,14 @@ static int hv_ce_set_next_event(unsigned long delta,

current_tick = hv_read_reference_counter();
current_tick += delta;
- hv_init_timer(0, current_tick);
+ hv_set_register(HV_REGISTER_STIMER0_COUNT, current_tick);
return 0;
}

static int hv_ce_shutdown(struct clock_event_device *evt)
{
- hv_init_timer(0, 0);
- hv_init_timer_config(0, 0);
+ hv_set_register(HV_REGISTER_STIMER0_COUNT, 0);
+ hv_set_register(HV_REGISTER_STIMER0_CONFIG, 0);
if (direct_mode_enabled)
hv_disable_stimer0_percpu_irq(stimer0_irq);

@@ -105,7 +105,7 @@ static int hv_ce_set_oneshot(struct clock_event_device *evt)
timer_cfg.direct_mode = 0;
timer_cfg.sintx = stimer0_message_sint;
}
- hv_init_timer_config(0, timer_cfg.as_uint64);
+ hv_set_register(HV_REGISTER_STIMER0_CONFIG, timer_cfg.as_uint64);
return 0;
}

@@ -331,7 +331,7 @@ static u64 notrace read_hv_clock_tsc(void)
u64 current_tick = hv_read_tsc_page(hv_get_tsc_page());

if (current_tick == U64_MAX)
- hv_get_time_ref_count(current_tick);
+ current_tick = hv_get_register(HV_REGISTER_TIME_REF_COUNT);

return current_tick;
}
@@ -352,9 +352,9 @@ static void suspend_hv_clock_tsc(struct clocksource *arg)
u64 tsc_msr;

/* Disable the TSC page */
- hv_get_reference_tsc(tsc_msr);
+ tsc_msr = hv_get_register(HV_REGISTER_REFERENCE_TSC);
tsc_msr &= ~BIT_ULL(0);
- hv_set_reference_tsc(tsc_msr);
+ hv_set_register(HV_REGISTER_REFERENCE_TSC, tsc_msr);
}


@@ -364,10 +364,10 @@ static void resume_hv_clock_tsc(struct clocksource *arg)
u64 tsc_msr;

/* Re-enable the TSC page */
- hv_get_reference_tsc(tsc_msr);
+ tsc_msr = hv_get_register(HV_REGISTER_REFERENCE_TSC);
tsc_msr &= GENMASK_ULL(11, 0);
tsc_msr |= BIT_ULL(0) | (u64)phys_addr;
- hv_set_reference_tsc(tsc_msr);
+ hv_set_register(HV_REGISTER_REFERENCE_TSC, tsc_msr);
}

static int hv_cs_enable(struct clocksource *cs)
@@ -389,14 +389,12 @@ static int hv_cs_enable(struct clocksource *cs)

static u64 notrace read_hv_clock_msr(void)
{
- u64 current_tick;
/*
* Read the partition counter to get the current tick count. This count
* is set to 0 when the partition is created and is incremented in
* 100 nanosecond units.
*/
- hv_get_time_ref_count(current_tick);
- return current_tick;
+ return hv_get_register(HV_REGISTER_TIME_REF_COUNT);
}

static u64 notrace read_hv_clock_msr_cs(struct clocksource *arg)
@@ -439,10 +437,10 @@ static bool __init hv_init_tsc_clocksource(void)
* (which already has at least the low 12 bits set to zero since
* it is page aligned). Also set the "enable" bit, which is bit 0.
*/
- hv_get_reference_tsc(tsc_msr);
+ tsc_msr = hv_get_register(HV_REGISTER_REFERENCE_TSC);
tsc_msr &= GENMASK_ULL(11, 0);
tsc_msr = tsc_msr | 0x1 | (u64)phys_addr;
- hv_set_reference_tsc(tsc_msr);
+ hv_set_register(HV_REGISTER_REFERENCE_TSC, tsc_msr);

hv_set_clocksource_vdso(hyperv_cs_tsc);
clocksource_register_hz(&hyperv_cs_tsc, NSEC_PER_SEC/100);
diff --git a/drivers/hv/hv.c b/drivers/hv/hv.c
index cca8d5e..0c1fa69 100644
--- a/drivers/hv/hv.c
+++ b/drivers/hv/hv.c
@@ -198,34 +198,36 @@ void hv_synic_enable_regs(unsigned int cpu)
union hv_synic_scontrol sctrl;

/* Setup the Synic's message page */
- hv_get_simp(simp.as_uint64);
+ simp.as_uint64 = hv_get_register(HV_REGISTER_SIMP);
simp.simp_enabled = 1;
simp.base_simp_gpa = virt_to_phys(hv_cpu->synic_message_page)
>> HV_HYP_PAGE_SHIFT;

- hv_set_simp(simp.as_uint64);
+ hv_set_register(HV_REGISTER_SIMP, simp.as_uint64);

/* Setup the Synic's event page */
- hv_get_siefp(siefp.as_uint64);
+ siefp.as_uint64 = hv_get_register(HV_REGISTER_SIEFP);
siefp.siefp_enabled = 1;
siefp.base_siefp_gpa = virt_to_phys(hv_cpu->synic_event_page)
>> HV_HYP_PAGE_SHIFT;

- hv_set_siefp(siefp.as_uint64);
+ hv_set_register(HV_REGISTER_SIEFP, siefp.as_uint64);

/* Setup the shared SINT. */
- hv_get_synint_state(VMBUS_MESSAGE_SINT, shared_sint.as_uint64);
+ shared_sint.as_uint64 = hv_get_register(HV_REGISTER_SINT0 +
+ VMBUS_MESSAGE_SINT);

shared_sint.vector = hv_get_vector();
shared_sint.masked = false;
shared_sint.auto_eoi = hv_recommend_using_aeoi();
- hv_set_synint_state(VMBUS_MESSAGE_SINT, shared_sint.as_uint64);
+ hv_set_register(HV_REGISTER_SINT0 + VMBUS_MESSAGE_SINT,
+ shared_sint.as_uint64);

/* Enable the global synic bit */
- hv_get_synic_state(sctrl.as_uint64);
+ sctrl.as_uint64 = hv_get_register(HV_REGISTER_SCONTROL);
sctrl.enable = 1;

- hv_set_synic_state(sctrl.as_uint64);
+ hv_set_register(HV_REGISTER_SCONTROL, sctrl.as_uint64);
}

int hv_synic_init(unsigned int cpu)
@@ -247,32 +249,35 @@ void hv_synic_disable_regs(unsigned int cpu)
union hv_synic_siefp siefp;
union hv_synic_scontrol sctrl;

- hv_get_synint_state(VMBUS_MESSAGE_SINT, shared_sint.as_uint64);
+ shared_sint.as_uint64 = hv_get_register(HV_REGISTER_SINT0 +
+ VMBUS_MESSAGE_SINT);

shared_sint.masked = 1;

/* Need to correctly cleanup in the case of SMP!!! */
/* Disable the interrupt */
- hv_set_synint_state(VMBUS_MESSAGE_SINT, shared_sint.as_uint64);
+ hv_set_register(HV_REGISTER_SINT0 + VMBUS_MESSAGE_SINT,
+ shared_sint.as_uint64);

- hv_get_simp(simp.as_uint64);
+ simp.as_uint64 = hv_get_register(HV_REGISTER_SIMP);
simp.simp_enabled = 0;
simp.base_simp_gpa = 0;

- hv_set_simp(simp.as_uint64);
+ hv_set_register(HV_REGISTER_SIMP, simp.as_uint64);

- hv_get_siefp(siefp.as_uint64);
+ siefp.as_uint64 = hv_get_register(HV_REGISTER_SIEFP);
siefp.siefp_enabled = 0;
siefp.base_siefp_gpa = 0;

- hv_set_siefp(siefp.as_uint64);
+ hv_set_register(HV_REGISTER_SIEFP, siefp.as_uint64);

/* Disable the global synic bit */
- hv_get_synic_state(sctrl.as_uint64);
+ sctrl.as_uint64 = hv_get_register(HV_REGISTER_SCONTROL);
sctrl.enable = 0;
- hv_set_synic_state(sctrl.as_uint64);
+ hv_set_register(HV_REGISTER_SCONTROL, sctrl.as_uint64);
}

+
int hv_synic_cleanup(unsigned int cpu)
{
struct vmbus_channel *channel, *sc;
diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
index 10dce9f..9e63170 100644
--- a/drivers/hv/vmbus_drv.c
+++ b/drivers/hv/vmbus_drv.c
@@ -1521,7 +1521,7 @@ static int vmbus_bus_init(void)
* Register for panic kmsg callback only if the right
* capability is supported by the hypervisor.
*/
- hv_get_crash_ctl(hyperv_crash_ctl);
+ hyperv_crash_ctl = hv_get_register(HV_REGISTER_CRASH_CTL);
if (hyperv_crash_ctl & HV_CRASH_CTL_CRASH_NOTIFY_MSG)
hv_kmsg_dump_register();

diff --git a/include/asm-generic/mshyperv.h b/include/asm-generic/mshyperv.h
index 694b5bc..163d8b0 100644
--- a/include/asm-generic/mshyperv.h
+++ b/include/asm-generic/mshyperv.h
@@ -88,7 +88,7 @@ static inline void vmbus_signal_eom(struct hv_message *msg, u32 old_msg_type)
* possibly deliver another msg from the
* hypervisor
*/
- hv_signal_eom();
+ hv_set_register(HV_REGISTER_EOM, 0);
}
}

--
1.8.3.1