hyperv-tlfs: Change prefix of generic HV_REGISTER_* MSRs to HV_MSR_*

The HV_REGISTER_ are used as arguments to hv_set/get_register(), which
delegate to arch-specific mechanisms for getting/setting synthetic
Hyper-V MSRs.

On arm64, HV_REGISTER_ defines are synthetic VP registers accessed via
the get/set vp registers hypercalls. The naming matches the TLFS
document, although these register names are not specific to arm64.

However, on x86 the prefix HV_REGISTER_ indicates Hyper-V MSRs accessed
via rdmsrl()/wrmsrl(). This is not consistent with the TLFS doc, where
HV_REGISTER_ is *only* used for used for VP register names used by
the get/set register hypercalls.

To fix this inconsistency and prevent future confusion, change the
arch-generic aliases used by callers of hv_set/get_register() to have
the prefix HV_MSR_ instead of HV_REGISTER_.

Use the prefix HV_X64_MSR_ for the x86-only Hyper-V MSRs. On x86, the
generic HV_MSR_'s point to the corresponding HV_X64_MSR_.

Move the arm64 HV_REGISTER_* defines to the asm-generic hyperv-tlfs.h,
since these are not specific to arm64. On arm64, the generic HV_MSR_'s
point to the corresponding HV_REGISTER_.

While at it, rename hv_get/set_registers() and related functions to
hv_get/set_msr(), hv_get/set_nested_msr(), etc. These are only used for
Hyper-V MSRs and this naming makes that clear.

Signed-off-by: Nuno Das Neves <nunodasneves@linux.microsoft.com>
Reviewed-by: Wei Liu <wei.liu@kernel.org>
Reviewed-by: Michael Kelley <mhklinux@outlook.com>
Link: https://lore.kernel.org/r/1708440933-27125-1-git-send-email-nunodasneves@linux.microsoft.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Message-ID: <1708440933-27125-1-git-send-email-nunodasneves@linux.microsoft.com>

2 files changed, 27 insertions, 31 deletions

diff --git a/drivers/hv/hv.c b/drivers/hv/hv.c
index 51e5018ac9b26..a8ad728354cb0 100644
--- a/drivers/hv/hv.c
+++ b/drivers/hv/hv.c
@@ -270,7 +270,7 @@ void hv_synic_enable_regs(unsigned int cpu)
 	union hv_synic_scontrol sctrl;
 
 	/* Setup the Synic's message page */
-	simp.as_uint64 = hv_get_register(HV_REGISTER_SIMP);
+	simp.as_uint64 = hv_get_msr(HV_MSR_SIMP);
 	simp.simp_enabled = 1;
 
 	if (ms_hyperv.paravisor_present || hv_root_partition) {
@@ -286,10 +286,10 @@ void hv_synic_enable_regs(unsigned int cpu)
 			>> HV_HYP_PAGE_SHIFT;
 	}
 
-	hv_set_register(HV_REGISTER_SIMP, simp.as_uint64);
+	hv_set_msr(HV_MSR_SIMP, simp.as_uint64);
 
 	/* Setup the Synic's event page */
-	siefp.as_uint64 = hv_get_register(HV_REGISTER_SIEFP);
+	siefp.as_uint64 = hv_get_msr(HV_MSR_SIEFP);
 	siefp.siefp_enabled = 1;
 
 	if (ms_hyperv.paravisor_present || hv_root_partition) {
@@ -305,13 +305,12 @@ void hv_synic_enable_regs(unsigned int cpu)
 			>> HV_HYP_PAGE_SHIFT;
 	}
 
-	hv_set_register(HV_REGISTER_SIEFP, siefp.as_uint64);
+	hv_set_msr(HV_MSR_SIEFP, siefp.as_uint64);
 
 	/* Setup the shared SINT. */
 	if (vmbus_irq != -1)
 		enable_percpu_irq(vmbus_irq, 0);
-	shared_sint.as_uint64 = hv_get_register(HV_REGISTER_SINT0 +
-					VMBUS_MESSAGE_SINT);
+	shared_sint.as_uint64 = hv_get_msr(HV_MSR_SINT0 + VMBUS_MESSAGE_SINT);
 
 	shared_sint.vector = vmbus_interrupt;
 	shared_sint.masked = false;
@@ -326,14 +325,13 @@ void hv_synic_enable_regs(unsigned int cpu)
 #else
 	shared_sint.auto_eoi = 0;
 #endif
-	hv_set_register(HV_REGISTER_SINT0 + VMBUS_MESSAGE_SINT,
-				shared_sint.as_uint64);
+	hv_set_msr(HV_MSR_SINT0 + VMBUS_MESSAGE_SINT, shared_sint.as_uint64);
 
 	/* Enable the global synic bit */
-	sctrl.as_uint64 = hv_get_register(HV_REGISTER_SCONTROL);
+	sctrl.as_uint64 = hv_get_msr(HV_MSR_SCONTROL);
 	sctrl.enable = 1;
 
-	hv_set_register(HV_REGISTER_SCONTROL, sctrl.as_uint64);
+	hv_set_msr(HV_MSR_SCONTROL, sctrl.as_uint64);
 }
 
 int hv_synic_init(unsigned int cpu)
@@ -357,17 +355,15 @@ void hv_synic_disable_regs(unsigned int cpu)
 	union hv_synic_siefp siefp;
 	union hv_synic_scontrol sctrl;
 
-	shared_sint.as_uint64 = hv_get_register(HV_REGISTER_SINT0 +
-					VMBUS_MESSAGE_SINT);
+	shared_sint.as_uint64 = hv_get_msr(HV_MSR_SINT0 + VMBUS_MESSAGE_SINT);
 
 	shared_sint.masked = 1;
 
 	/* Need to correctly cleanup in the case of SMP!!! */
 	/* Disable the interrupt */
-	hv_set_register(HV_REGISTER_SINT0 + VMBUS_MESSAGE_SINT,
-				shared_sint.as_uint64);
+	hv_set_msr(HV_MSR_SINT0 + VMBUS_MESSAGE_SINT, shared_sint.as_uint64);
 
-	simp.as_uint64 = hv_get_register(HV_REGISTER_SIMP);
+	simp.as_uint64 = hv_get_msr(HV_MSR_SIMP);
 	/*
 	 * In Isolation VM, sim and sief pages are allocated by
 	 * paravisor. These pages also will be used by kdump
@@ -382,9 +378,9 @@ void hv_synic_disable_regs(unsigned int cpu)
 		simp.base_simp_gpa = 0;
 	}
 
-	hv_set_register(HV_REGISTER_SIMP, simp.as_uint64);
+	hv_set_msr(HV_MSR_SIMP, simp.as_uint64);
 
-	siefp.as_uint64 = hv_get_register(HV_REGISTER_SIEFP);
+	siefp.as_uint64 = hv_get_msr(HV_MSR_SIEFP);
 	siefp.siefp_enabled = 0;
 
 	if (ms_hyperv.paravisor_present || hv_root_partition) {
@@ -394,12 +390,12 @@ void hv_synic_disable_regs(unsigned int cpu)
 		siefp.base_siefp_gpa = 0;
 	}
 
-	hv_set_register(HV_REGISTER_SIEFP, siefp.as_uint64);
+	hv_set_msr(HV_MSR_SIEFP, siefp.as_uint64);
 
 	/* Disable the global synic bit */
-	sctrl.as_uint64 = hv_get_register(HV_REGISTER_SCONTROL);
+	sctrl.as_uint64 = hv_get_msr(HV_MSR_SCONTROL);
 	sctrl.enable = 0;
-	hv_set_register(HV_REGISTER_SCONTROL, sctrl.as_uint64);
+	hv_set_msr(HV_MSR_SCONTROL, sctrl.as_uint64);
 
 	if (vmbus_irq != -1)
 		disable_percpu_irq(vmbus_irq);
diff --git a/drivers/hv/hv_common.c b/drivers/hv/hv_common.c
index 0285a74363b3d..2f1dd4b07f9a4 100644
--- a/drivers/hv/hv_common.c
+++ b/drivers/hv/hv_common.c
@@ -227,19 +227,19 @@ static void hv_kmsg_dump(struct kmsg_dumper *dumper,
 	 * contain the size of the panic data in that page. Rest of the
 	 * registers are no-op when the NOTIFY_MSG flag is set.
 	 */
-	hv_set_register(HV_REGISTER_CRASH_P0, 0);
-	hv_set_register(HV_REGISTER_CRASH_P1, 0);
-	hv_set_register(HV_REGISTER_CRASH_P2, 0);
-	hv_set_register(HV_REGISTER_CRASH_P3, virt_to_phys(hv_panic_page));
-	hv_set_register(HV_REGISTER_CRASH_P4, bytes_written);
+	hv_set_msr(HV_MSR_CRASH_P0, 0);
+	hv_set_msr(HV_MSR_CRASH_P1, 0);
+	hv_set_msr(HV_MSR_CRASH_P2, 0);
+	hv_set_msr(HV_MSR_CRASH_P3, virt_to_phys(hv_panic_page));
+	hv_set_msr(HV_MSR_CRASH_P4, bytes_written);
 
 	/*
 	 * Let Hyper-V know there is crash data available along with
 	 * the panic message.
 	 */
-	hv_set_register(HV_REGISTER_CRASH_CTL,
-			(HV_CRASH_CTL_CRASH_NOTIFY |
-			 HV_CRASH_CTL_CRASH_NOTIFY_MSG));
+	hv_set_msr(HV_MSR_CRASH_CTL,
+		   (HV_CRASH_CTL_CRASH_NOTIFY |
+		    HV_CRASH_CTL_CRASH_NOTIFY_MSG));
 }
 
 static struct kmsg_dumper hv_kmsg_dumper = {
@@ -310,7 +310,7 @@ int __init hv_common_init(void)
 		 * Register for panic kmsg callback only if the right
 		 * capability is supported by the hypervisor.
 		 */
-		hyperv_crash_ctl = hv_get_register(HV_REGISTER_CRASH_CTL);
+		hyperv_crash_ctl = hv_get_msr(HV_MSR_CRASH_CTL);
 		if (hyperv_crash_ctl & HV_CRASH_CTL_CRASH_NOTIFY_MSG)
 			hv_kmsg_dump_register();
 
@@ -409,7 +409,7 @@ int hv_common_cpu_init(unsigned int cpu)
 		*inputarg = mem;
 	}
 
-	msr_vp_index = hv_get_register(HV_REGISTER_VP_INDEX);
+	msr_vp_index = hv_get_msr(HV_MSR_VP_INDEX);
 
 	hv_vp_index[cpu] = msr_vp_index;
 
@@ -506,7 +506,7 @@ EXPORT_SYMBOL_GPL(hv_is_hibernation_supported);
  */
 static u64 __hv_read_ref_counter(void)
 {
-	return hv_get_register(HV_REGISTER_TIME_REF_COUNT);
+	return hv_get_msr(HV_MSR_TIME_REF_COUNT);
 }
 
 u64 (*hv_read_reference_counter)(void) = __hv_read_ref_counter;