Merge tag 'hyperv-next-signed-20210426' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux

Pull Hyper-V updates from Wei Liu:

 - VMBus enhancement

 - Free page reporting support for Hyper-V balloon driver

 - Some patches for running Linux as Arm64 Hyper-V guest

 - A few misc clean-up patches

* tag 'hyperv-next-signed-20210426' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux: (30 commits)
  drivers: hv: Create a consistent pattern for checking Hyper-V hypercall status
  x86/hyperv: Move hv_do_rep_hypercall to asm-generic
  video: hyperv_fb: Add ratelimit on error message
  Drivers: hv: vmbus: Increase wait time for VMbus unload
  Drivers: hv: vmbus: Initialize unload_event statically
  Drivers: hv: vmbus: Check for pending channel interrupts before taking a CPU offline
  Drivers: hv: vmbus: Drivers: hv: vmbus: Introduce CHANNELMSG_MODIFYCHANNEL_RESPONSE
  Drivers: hv: vmbus: Introduce and negotiate VMBus protocol version 5.3
  Drivers: hv: vmbus: Use after free in __vmbus_open()
  Drivers: hv: vmbus: remove unused function
  Drivers: hv: vmbus: Remove unused linux/version.h header
  x86/hyperv: remove unused linux/version.h header
  x86/Hyper-V: Support for free page reporting
  x86/hyperv: Fix unused variable 'hi' warning in hv_apic_read
  x86/hyperv: Fix unused variable 'msr_val' warning in hv_qlock_wait
  hv: hyperv.h: a few mundane typo fixes
  drivers: hv: Fix EXPORT_SYMBOL and tab spaces issue
  Drivers: hv: vmbus: Drop error message when 'No request id available'
  asm-generic/hyperv: Add missing function prototypes per -W1 warnings
  clocksource/drivers/hyper-v: Move handling of STIMER0 interrupts
  ...

7 files changed, 91 insertions, 89 deletions

diff --git a/arch/x86/hyperv/hv_apic.c b/arch/x86/hyperv/hv_apic.c
index 284e73661a18..90e682a92820 100644
--- a/arch/x86/hyperv/hv_apic.c
+++ b/arch/x86/hyperv/hv_apic.c
@@ -60,9 +60,11 @@ static u32 hv_apic_read(u32 reg)
 	switch (reg) {
 	case APIC_EOI:
 		rdmsr(HV_X64_MSR_EOI, reg_val, hi);
+		(void)hi;
 		return reg_val;
 	case APIC_TASKPRI:
 		rdmsr(HV_X64_MSR_TPR, reg_val, hi);
+		(void)hi;
 		return reg_val;
 
 	default:
@@ -103,7 +105,7 @@ static bool __send_ipi_mask_ex(const struct cpumask *mask, int vector)
 	struct hv_send_ipi_ex *ipi_arg;
 	unsigned long flags;
 	int nr_bank = 0;
-	int ret = 1;
+	u64 status = HV_STATUS_INVALID_PARAMETER;
 
 	if (!(ms_hyperv.hints & HV_X64_EX_PROCESSOR_MASKS_RECOMMENDED))
 		return false;
@@ -128,19 +130,19 @@ static bool __send_ipi_mask_ex(const struct cpumask *mask, int vector)
 	if (!nr_bank)
 		ipi_arg->vp_set.format = HV_GENERIC_SET_ALL;
 
-	ret = hv_do_rep_hypercall(HVCALL_SEND_IPI_EX, 0, nr_bank,
+	status = hv_do_rep_hypercall(HVCALL_SEND_IPI_EX, 0, nr_bank,
 			      ipi_arg, NULL);
 
 ipi_mask_ex_done:
 	local_irq_restore(flags);
-	return ((ret == 0) ? true : false);
+	return hv_result_success(status);
 }
 
 static bool __send_ipi_mask(const struct cpumask *mask, int vector)
 {
 	int cur_cpu, vcpu;
 	struct hv_send_ipi ipi_arg;
-	int ret = 1;
+	u64 status;
 
 	trace_hyperv_send_ipi_mask(mask, vector);
 
@@ -184,9 +186,9 @@ static bool __send_ipi_mask(const struct cpumask *mask, int vector)
 		__set_bit(vcpu, (unsigned long *)&ipi_arg.cpu_mask);
 	}
 
-	ret = hv_do_fast_hypercall16(HVCALL_SEND_IPI, ipi_arg.vector,
+	status = hv_do_fast_hypercall16(HVCALL_SEND_IPI, ipi_arg.vector,
 				     ipi_arg.cpu_mask);
-	return ((ret == 0) ? true : false);
+	return hv_result_success(status);
 
 do_ex_hypercall:
 	return __send_ipi_mask_ex(mask, vector);
@@ -195,6 +197,7 @@ do_ex_hypercall:
 static bool __send_ipi_one(int cpu, int vector)
 {
 	int vp = hv_cpu_number_to_vp_number(cpu);
+	u64 status;
 
 	trace_hyperv_send_ipi_one(cpu, vector);
 
@@ -207,7 +210,8 @@ static bool __send_ipi_one(int cpu, int vector)
 	if (vp >= 64)
 		return __send_ipi_mask_ex(cpumask_of(cpu), vector);
 
-	return !hv_do_fast_hypercall16(HVCALL_SEND_IPI, vector, BIT_ULL(vp));
+	status = hv_do_fast_hypercall16(HVCALL_SEND_IPI, vector, BIT_ULL(vp));
+	return hv_result_success(status);
 }
 
 static void hv_send_ipi(int cpu, int vector)
diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c
index e7b94f636cc1..bb0ae4b5c00f 100644
--- a/arch/x86/hyperv/hv_init.c
+++ b/arch/x86/hyperv/hv_init.c
@@ -54,28 +54,6 @@ EXPORT_SYMBOL_GPL(hyperv_pcpu_output_arg);
 u32 hv_max_vp_index;
 EXPORT_SYMBOL_GPL(hv_max_vp_index);
 
-void *hv_alloc_hyperv_page(void)
-{
-	BUILD_BUG_ON(PAGE_SIZE != HV_HYP_PAGE_SIZE);
-
-	return (void *)__get_free_page(GFP_KERNEL);
-}
-EXPORT_SYMBOL_GPL(hv_alloc_hyperv_page);
-
-void *hv_alloc_hyperv_zeroed_page(void)
-{
-        BUILD_BUG_ON(PAGE_SIZE != HV_HYP_PAGE_SIZE);
-
-        return (void *)__get_free_page(GFP_KERNEL | __GFP_ZERO);
-}
-EXPORT_SYMBOL_GPL(hv_alloc_hyperv_zeroed_page);
-
-void hv_free_hyperv_page(unsigned long addr)
-{
-	free_page(addr);
-}
-EXPORT_SYMBOL_GPL(hv_free_hyperv_page);
-
 static int hv_cpu_init(unsigned int cpu)
 {
 	u64 msr_vp_index;
@@ -97,7 +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;
 
@@ -349,7 +327,7 @@ static void __init hv_stimer_setup_percpu_clockev(void)
 	 * Ignore any errors in setting up stimer clockevents
 	 * as we can run with the LAPIC timer as a fallback.
 	 */
-	(void)hv_stimer_alloc();
+	(void)hv_stimer_alloc(false);
 
 	/*
 	 * Still register the LAPIC timer, because the direct-mode STIMER is
@@ -369,7 +347,7 @@ static void __init hv_get_partition_id(void)
 	local_irq_save(flags);
 	output_page = *this_cpu_ptr(hyperv_pcpu_output_arg);
 	status = hv_do_hypercall(HVCALL_GET_PARTITION_ID, NULL, output_page);
-	if ((status & HV_HYPERCALL_RESULT_MASK) != HV_STATUS_SUCCESS) {
+	if (!hv_result_success(status)) {
 		/* No point in proceeding if this failed */
 		pr_err("Failed to get partition ID: %lld\n", status);
 		BUG();
@@ -520,6 +498,8 @@ void __init hyperv_init(void)
 		x86_init.irqs.create_pci_msi_domain = hv_create_pci_msi_domain;
 #endif
 
+	/* Query the VMs extended capability once, so that it can be cached. */
+	hv_query_ext_cap(0);
 	return;
 
 remove_cpuhp_state:
@@ -593,33 +573,6 @@ void hyperv_report_panic(struct pt_regs *regs, long err, bool in_die)
 }
 EXPORT_SYMBOL_GPL(hyperv_report_panic);
 
-/**
- * hyperv_report_panic_msg - report panic message to Hyper-V
- * @pa: physical address of the panic page containing the message
- * @size: size of the message in the page
- */
-void hyperv_report_panic_msg(phys_addr_t pa, size_t size)
-{
-	/*
-	 * P3 to contain the physical address of the panic page & P4 to
-	 * contain the size of the panic data in that page. Rest of the
-	 * registers are no-op when the NOTIFY_MSG flag is set.
-	 */
-	wrmsrl(HV_X64_MSR_CRASH_P0, 0);
-	wrmsrl(HV_X64_MSR_CRASH_P1, 0);
-	wrmsrl(HV_X64_MSR_CRASH_P2, 0);
-	wrmsrl(HV_X64_MSR_CRASH_P3, pa);
-	wrmsrl(HV_X64_MSR_CRASH_P4, size);
-
-	/*
-	 * Let Hyper-V know there is crash data available along with
-	 * the panic message.
-	 */
-	wrmsrl(HV_X64_MSR_CRASH_CTL,
-	       (HV_CRASH_CTL_CRASH_NOTIFY | HV_CRASH_CTL_CRASH_NOTIFY_MSG));
-}
-EXPORT_SYMBOL_GPL(hyperv_report_panic_msg);
-
 bool hv_is_hyperv_initialized(void)
 {
 	union hv_x64_msr_hypercall_contents hypercall_msr;
@@ -650,7 +603,7 @@ EXPORT_SYMBOL_GPL(hv_is_hibernation_supported);
 
 enum hv_isolation_type hv_get_isolation_type(void)
 {
-	if (!(ms_hyperv.features_b & HV_ISOLATION))
+	if (!(ms_hyperv.priv_high & HV_ISOLATION))
 		return HV_ISOLATION_TYPE_NONE;
 	return FIELD_GET(HV_ISOLATION_TYPE, ms_hyperv.isolation_config_b);
 }
@@ -661,3 +614,50 @@ bool hv_is_isolation_supported(void)
 	return hv_get_isolation_type() != HV_ISOLATION_TYPE_NONE;
 }
 EXPORT_SYMBOL_GPL(hv_is_isolation_supported);
+
+/* Bit mask of the extended capability to query: see HV_EXT_CAPABILITY_xxx */
+bool hv_query_ext_cap(u64 cap_query)
+{
+	/*
+	 * The address of the 'hv_extended_cap' variable will be used as an
+	 * output parameter to the hypercall below and so it should be
+	 * compatible with 'virt_to_phys'. Which means, it's address should be
+	 * directly mapped. Use 'static' to keep it compatible; stack variables
+	 * can be virtually mapped, making them imcompatible with
+	 * 'virt_to_phys'.
+	 * Hypercall input/output addresses should also be 8-byte aligned.
+	 */
+	static u64 hv_extended_cap __aligned(8);
+	static bool hv_extended_cap_queried;
+	u64 status;
+
+	/*
+	 * Querying extended capabilities is an extended hypercall. Check if the
+	 * partition supports extended hypercall, first.
+	 */
+	if (!(ms_hyperv.priv_high & HV_ENABLE_EXTENDED_HYPERCALLS))
+		return false;
+
+	/* Extended capabilities do not change at runtime. */
+	if (hv_extended_cap_queried)
+		return hv_extended_cap & cap_query;
+
+	status = hv_do_hypercall(HV_EXT_CALL_QUERY_CAPABILITIES, NULL,
+				 &hv_extended_cap);
+
+	/*
+	 * The query extended capabilities hypercall should not fail under
+	 * any normal circumstances. Avoid repeatedly making the hypercall, on
+	 * error.
+	 */
+	hv_extended_cap_queried = true;
+	status &= HV_HYPERCALL_RESULT_MASK;
+	if (status != HV_STATUS_SUCCESS) {
+		pr_err("Hyper-V: Extended query capabilities hypercall failed 0x%llx\n",
+		       status);
+		return false;
+	}
+
+	return hv_extended_cap & cap_query;
+}
+EXPORT_SYMBOL_GPL(hv_query_ext_cap);
diff --git a/arch/x86/hyperv/hv_proc.c b/arch/x86/hyperv/hv_proc.c
index 60461e598239..68a0843d4750 100644
--- a/arch/x86/hyperv/hv_proc.c
+++ b/arch/x86/hyperv/hv_proc.c
@@ -1,6 +1,5 @@
 // SPDX-License-Identifier: GPL-2.0
 #include <linux/types.h>
-#include <linux/version.h>
 #include <linux/vmalloc.h>
 #include <linux/mm.h>
 #include <linux/clockchips.h>
@@ -93,10 +92,9 @@ int hv_call_deposit_pages(int node, u64 partition_id, u32 num_pages)
 	status = hv_do_rep_hypercall(HVCALL_DEPOSIT_MEMORY,
 				     page_count, 0, input_page, NULL);
 	local_irq_restore(flags);
-
-	if ((status & HV_HYPERCALL_RESULT_MASK) != HV_STATUS_SUCCESS) {
+	if (!hv_result_success(status)) {
 		pr_err("Failed to deposit pages: %lld\n", status);
-		ret = status;
+		ret = hv_result(status);
 		goto err_free_allocations;
 	}
 
@@ -122,7 +120,7 @@ int hv_call_add_logical_proc(int node, u32 lp_index, u32 apic_id)
 	struct hv_add_logical_processor_out *output;
 	u64 status;
 	unsigned long flags;
-	int ret = 0;
+	int ret = HV_STATUS_SUCCESS;
 	int pxm = node_to_pxm(node);
 
 	/*
@@ -148,13 +146,11 @@ int hv_call_add_logical_proc(int node, u32 lp_index, u32 apic_id)
 					 input, output);
 		local_irq_restore(flags);
 
-		status &= HV_HYPERCALL_RESULT_MASK;
-
-		if (status != HV_STATUS_INSUFFICIENT_MEMORY) {
-			if (status != HV_STATUS_SUCCESS) {
+		if (hv_result(status) != HV_STATUS_INSUFFICIENT_MEMORY) {
+			if (!hv_result_success(status)) {
 				pr_err("%s: cpu %u apic ID %u, %lld\n", __func__,
 				       lp_index, apic_id, status);
-				ret = status;
+				ret = hv_result(status);
 			}
 			break;
 		}
@@ -169,7 +165,7 @@ int hv_call_create_vp(int node, u64 partition_id, u32 vp_index, u32 flags)
 	struct hv_create_vp *input;
 	u64 status;
 	unsigned long irq_flags;
-	int ret = 0;
+	int ret = HV_STATUS_SUCCESS;
 	int pxm = node_to_pxm(node);
 
 	/* Root VPs don't seem to need pages deposited */
@@ -200,13 +196,11 @@ int hv_call_create_vp(int node, u64 partition_id, u32 vp_index, u32 flags)
 		status = hv_do_hypercall(HVCALL_CREATE_VP, input, NULL);
 		local_irq_restore(irq_flags);
 
-		status &= HV_HYPERCALL_RESULT_MASK;
-
-		if (status != HV_STATUS_INSUFFICIENT_MEMORY) {
-			if (status != HV_STATUS_SUCCESS) {
+		if (hv_result(status) != HV_STATUS_INSUFFICIENT_MEMORY) {
+			if (!hv_result_success(status)) {
 				pr_err("%s: vcpu %u, lp %u, %lld\n", __func__,
 				       vp_index, flags, status);
-				ret = status;
+				ret = hv_result(status);
 			}
 			break;
 		}
diff --git a/arch/x86/hyperv/hv_spinlock.c b/arch/x86/hyperv/hv_spinlock.c
index f3270c1fc48c..91cfe698bde0 100644
--- a/arch/x86/hyperv/hv_spinlock.c
+++ b/arch/x86/hyperv/hv_spinlock.c
@@ -25,7 +25,6 @@ static void hv_qlock_kick(int cpu)
 
 static void hv_qlock_wait(u8 *byte, u8 val)
 {
-	unsigned long msr_val;
 	unsigned long flags;
 
 	if (in_nmi())
@@ -48,8 +47,13 @@ static void hv_qlock_wait(u8 *byte, u8 val)
 	/*
 	 * Only issue the rdmsrl() when the lock state has not changed.
 	 */
-	if (READ_ONCE(*byte) == val)
+	if (READ_ONCE(*byte) == val) {
+		unsigned long msr_val;
+
 		rdmsrl(HV_X64_MSR_GUEST_IDLE, msr_val);
+
+		(void)msr_val;
+	}
 	local_irq_restore(flags);
 }
 
diff --git a/arch/x86/hyperv/irqdomain.c b/arch/x86/hyperv/irqdomain.c
index 4421a8d92e23..514fc64e23d5 100644
--- a/arch/x86/hyperv/irqdomain.c
+++ b/arch/x86/hyperv/irqdomain.c
@@ -63,10 +63,10 @@ static int hv_map_interrupt(union hv_device_id device_id, bool level,
 
 	local_irq_restore(flags);
 
-	if ((status & HV_HYPERCALL_RESULT_MASK) != HV_STATUS_SUCCESS)
+	if (!hv_result_success(status))
 		pr_err("%s: hypercall failed, status %lld\n", __func__, status);
 
-	return status & HV_HYPERCALL_RESULT_MASK;
+	return hv_result(status);
 }
 
 static int hv_unmap_interrupt(u64 id, struct hv_interrupt_entry *old_entry)
@@ -88,7 +88,7 @@ static int hv_unmap_interrupt(u64 id, struct hv_interrupt_entry *old_entry)
 	status = hv_do_hypercall(HVCALL_UNMAP_DEVICE_INTERRUPT, input, NULL);
 	local_irq_restore(flags);
 
-	return status & HV_HYPERCALL_RESULT_MASK;
+	return hv_result(status);
 }
 
 #ifdef CONFIG_PCI_MSI
diff --git a/arch/x86/hyperv/mmu.c b/arch/x86/hyperv/mmu.c
index 2c87350c1fb0..c0ba8874d9cb 100644
--- a/arch/x86/hyperv/mmu.c
+++ b/arch/x86/hyperv/mmu.c
@@ -58,7 +58,7 @@ static void hyperv_flush_tlb_others(const struct cpumask *cpus,
 	int cpu, vcpu, gva_n, max_gvas;
 	struct hv_tlb_flush **flush_pcpu;
 	struct hv_tlb_flush *flush;
-	u64 status = U64_MAX;
+	u64 status;
 	unsigned long flags;
 
 	trace_hyperv_mmu_flush_tlb_others(cpus, info);
@@ -161,7 +161,7 @@ do_ex_hypercall:
 check_status:
 	local_irq_restore(flags);
 
-	if (!(status & HV_HYPERCALL_RESULT_MASK))
+	if (hv_result_success(status))
 		return;
 do_native:
 	native_flush_tlb_others(cpus, info);
@@ -176,7 +176,7 @@ static u64 hyperv_flush_tlb_others_ex(const struct cpumask *cpus,
 	u64 status;
 
 	if (!(ms_hyperv.hints & HV_X64_EX_PROCESSOR_MASKS_RECOMMENDED))
-		return U64_MAX;
+		return HV_STATUS_INVALID_PARAMETER;
 
 	flush_pcpu = (struct hv_tlb_flush_ex **)
 		     this_cpu_ptr(hyperv_pcpu_input_arg);
@@ -201,7 +201,7 @@ static u64 hyperv_flush_tlb_others_ex(const struct cpumask *cpus,
 	flush->hv_vp_set.format = HV_GENERIC_SET_SPARSE_4K;
 	nr_bank = cpumask_to_vpset(&(flush->hv_vp_set), cpus);
 	if (nr_bank < 0)
-		return U64_MAX;
+		return HV_STATUS_INVALID_PARAMETER;
 
 	/*
 	 * We can flush not more than max_gvas with one hypercall. Flush the
diff --git a/arch/x86/hyperv/nested.c b/arch/x86/hyperv/nested.c
index dd0a843f766d..5d70968c8538 100644
--- a/arch/x86/hyperv/nested.c
+++ b/arch/x86/hyperv/nested.c
@@ -47,7 +47,7 @@ int hyperv_flush_guest_mapping(u64 as)
 				 flush, NULL);
 	local_irq_restore(flags);
 
-	if (!(status & HV_HYPERCALL_RESULT_MASK))
+	if (hv_result_success(status))
 		ret = 0;
 
 fault:
@@ -92,7 +92,7 @@ int hyperv_flush_guest_mapping_range(u64 as,
 {
 	struct hv_guest_mapping_flush_list **flush_pcpu;
 	struct hv_guest_mapping_flush_list *flush;
-	u64 status = 0;
+	u64 status;
 	unsigned long flags;
 	int ret = -ENOTSUPP;
 	int gpa_n = 0;
@@ -125,10 +125,10 @@ int hyperv_flush_guest_mapping_range(u64 as,
 
 	local_irq_restore(flags);
 
-	if (!(status & HV_HYPERCALL_RESULT_MASK))
+	if (hv_result_success(status))
 		ret = 0;
 	else
-		ret = status;
+		ret = hv_result(status);
 fault:
 	trace_hyperv_nested_flush_guest_mapping_range(as, ret);
 	return ret;