1 files changed, 140 insertions, 11 deletions

diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c
index 4638a52d8eae..b81047dec1da 100644
--- a/arch/x86/hyperv/hv_init.c
+++ b/arch/x86/hyperv/hv_init.c
@@ -10,6 +10,7 @@
 #include <linux/acpi.h>
 #include <linux/efi.h>
 #include <linux/types.h>
+#include <linux/bitfield.h>
 #include <asm/apic.h>
 #include <asm/desc.h>
 #include <asm/hypervisor.h>
@@ -26,8 +27,11 @@
 #include <linux/cpuhotplug.h>
 #include <linux/syscore_ops.h>
 #include <clocksource/hyperv_timer.h>
+#include <linux/highmem.h>
 
 int hyperv_init_cpuhp;
+u64 hv_current_partition_id = ~0ull;
+EXPORT_SYMBOL_GPL(hv_current_partition_id);
 
 void *hv_hypercall_pg;
 EXPORT_SYMBOL_GPL(hv_hypercall_pg);
@@ -44,6 +48,9 @@ EXPORT_SYMBOL_GPL(hv_vp_assist_page);
 void  __percpu **hyperv_pcpu_input_arg;
 EXPORT_SYMBOL_GPL(hyperv_pcpu_input_arg);
 
+void  __percpu **hyperv_pcpu_output_arg;
+EXPORT_SYMBOL_GPL(hyperv_pcpu_output_arg);
+
 u32 hv_max_vp_index;
 EXPORT_SYMBOL_GPL(hv_max_vp_index);
 
@@ -76,12 +83,19 @@ static int hv_cpu_init(unsigned int cpu)
 	void **input_arg;
 	struct page *pg;
 
-	input_arg = (void **)this_cpu_ptr(hyperv_pcpu_input_arg);
 	/* hv_cpu_init() can be called with IRQs disabled from hv_resume() */
-	pg = alloc_page(irqs_disabled() ? GFP_ATOMIC : GFP_KERNEL);
+	pg = alloc_pages(irqs_disabled() ? GFP_ATOMIC : GFP_KERNEL, hv_root_partition ? 1 : 0);
 	if (unlikely(!pg))
 		return -ENOMEM;
+
+	input_arg = (void **)this_cpu_ptr(hyperv_pcpu_input_arg);
 	*input_arg = page_address(pg);
+	if (hv_root_partition) {
+		void **output_arg;
+
+		output_arg = (void **)this_cpu_ptr(hyperv_pcpu_output_arg);
+		*output_arg = page_address(pg + 1);
+	}
 
 	hv_get_vp_index(msr_vp_index);
 
@@ -208,14 +222,23 @@ static int hv_cpu_die(unsigned int cpu)
 	unsigned int new_cpu;
 	unsigned long flags;
 	void **input_arg;
-	void *input_pg = NULL;
+	void *pg;
 
 	local_irq_save(flags);
 	input_arg = (void **)this_cpu_ptr(hyperv_pcpu_input_arg);
-	input_pg = *input_arg;
+	pg = *input_arg;
 	*input_arg = NULL;
+
+	if (hv_root_partition) {
+		void **output_arg;
+
+		output_arg = (void **)this_cpu_ptr(hyperv_pcpu_output_arg);
+		*output_arg = NULL;
+	}
+
 	local_irq_restore(flags);
-	free_page((unsigned long)input_pg);
+
+	free_pages((unsigned long)pg, hv_root_partition ? 1 : 0);
 
 	if (hv_vp_assist_page && hv_vp_assist_page[cpu])
 		wrmsrl(HV_X64_MSR_VP_ASSIST_PAGE, 0);
@@ -264,6 +287,9 @@ static int hv_suspend(void)
 	union hv_x64_msr_hypercall_contents hypercall_msr;
 	int ret;
 
+	if (hv_root_partition)
+		return -EPERM;
+
 	/*
 	 * Reset the hypercall page as it is going to be invalidated
 	 * accross hibernation. Setting hv_hypercall_pg to NULL ensures
@@ -315,6 +341,43 @@ static struct syscore_ops hv_syscore_ops = {
 	.resume		= hv_resume,
 };
 
+static void (* __initdata old_setup_percpu_clockev)(void);
+
+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();
+
+	/*
+	 * Still register the LAPIC timer, because the direct-mode STIMER is
+	 * not supported by old versions of Hyper-V. This also allows users
+	 * to switch to LAPIC timer via /sys, if they want to.
+	 */
+	if (old_setup_percpu_clockev)
+		old_setup_percpu_clockev();
+}
+
+static void __init hv_get_partition_id(void)
+{
+	struct hv_get_partition_id *output_page;
+	u64 status;
+	unsigned long flags;
+
+	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) {
+		/* No point in proceeding if this failed */
+		pr_err("Failed to get partition ID: %lld\n", status);
+		BUG();
+	}
+	hv_current_partition_id = output_page->partition_id;
+	local_irq_restore(flags);
+}
+
 /*
  * This function is to be invoked early in the boot sequence after the
  * hypervisor has been detected.
@@ -349,6 +412,12 @@ void __init hyperv_init(void)
 
 	BUG_ON(hyperv_pcpu_input_arg == NULL);
 
+	/* Allocate the per-CPU state for output arg for root */
+	if (hv_root_partition) {
+		hyperv_pcpu_output_arg = alloc_percpu(void *);
+		BUG_ON(hyperv_pcpu_output_arg == NULL);
+	}
+
 	/* Allocate percpu VP index */
 	hv_vp_index = kmalloc_array(num_possible_cpus(), sizeof(*hv_vp_index),
 				    GFP_KERNEL);
@@ -389,14 +458,45 @@ void __init hyperv_init(void)
 
 	rdmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
 	hypercall_msr.enable = 1;
-	hypercall_msr.guest_physical_address = vmalloc_to_pfn(hv_hypercall_pg);
-	wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
+
+	if (hv_root_partition) {
+		struct page *pg;
+		void *src, *dst;
+
+		/*
+		 * For the root partition, the hypervisor will set up its
+		 * hypercall page. The hypervisor guarantees it will not show
+		 * up in the root's address space. The root can't change the
+		 * location of the hypercall page.
+		 *
+		 * Order is important here. We must enable the hypercall page
+		 * so it is populated with code, then copy the code to an
+		 * executable page.
+		 */
+		wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
+
+		pg = vmalloc_to_page(hv_hypercall_pg);
+		dst = kmap(pg);
+		src = memremap(hypercall_msr.guest_physical_address << PAGE_SHIFT, PAGE_SIZE,
+				MEMREMAP_WB);
+		BUG_ON(!(src && dst));
+		memcpy(dst, src, HV_HYP_PAGE_SIZE);
+		memunmap(src);
+		kunmap(pg);
+	} else {
+		hypercall_msr.guest_physical_address = vmalloc_to_pfn(hv_hypercall_pg);
+		wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
+	}
 
 	/*
-	 * Ignore any errors in setting up stimer clockevents
-	 * as we can run with the LAPIC timer as a fallback.
+	 * hyperv_init() is called before LAPIC is initialized: see
+	 * apic_intr_mode_init() -> x86_platform.apic_post_init() and
+	 * apic_bsp_setup() -> setup_local_APIC(). The direct-mode STIMER
+	 * depends on LAPIC, so hv_stimer_alloc() should be called from
+	 * x86_init.timers.setup_percpu_clockev.
 	 */
-	(void)hv_stimer_alloc();
+	old_setup_percpu_clockev = x86_init.timers.setup_percpu_clockev;
+	x86_init.timers.setup_percpu_clockev = hv_stimer_setup_percpu_clockev;
 
 	hv_apic_init();
 
@@ -405,6 +505,21 @@ void __init hyperv_init(void)
 	register_syscore_ops(&hv_syscore_ops);
 
 	hyperv_init_cpuhp = cpuhp;
+
+	if (cpuid_ebx(HYPERV_CPUID_FEATURES) & HV_ACCESS_PARTITION_ID)
+		hv_get_partition_id();
+
+	BUG_ON(hv_root_partition && hv_current_partition_id == ~0ull);
+
+#ifdef CONFIG_PCI_MSI
+	/*
+	 * If we're running as root, we want to create our own PCI MSI domain.
+	 * We can't set this in hv_pci_init because that would be too late.
+	 */
+	if (hv_root_partition)
+		x86_init.irqs.create_pci_msi_domain = hv_create_pci_msi_domain;
+#endif
+
 	return;
 
 remove_cpuhp_state:
@@ -529,6 +644,20 @@ EXPORT_SYMBOL_GPL(hv_is_hyperv_initialized);
 
 bool hv_is_hibernation_supported(void)
 {
-	return acpi_sleep_state_supported(ACPI_STATE_S4);
+	return !hv_root_partition && acpi_sleep_state_supported(ACPI_STATE_S4);
 }
 EXPORT_SYMBOL_GPL(hv_is_hibernation_supported);
+
+enum hv_isolation_type hv_get_isolation_type(void)
+{
+	if (!(ms_hyperv.features_b & HV_ISOLATION))
+		return HV_ISOLATION_TYPE_NONE;
+	return FIELD_GET(HV_ISOLATION_TYPE, ms_hyperv.isolation_config_b);
+}
+EXPORT_SYMBOL_GPL(hv_get_isolation_type);
+
+bool hv_is_isolation_supported(void)
+{
+	return hv_get_isolation_type() != HV_ISOLATION_TYPE_NONE;
+}
+EXPORT_SYMBOL_GPL(hv_is_isolation_supported);