1 files changed, 429 insertions, 0 deletions
diff --git a/drivers/hv/hv.c b/drivers/hv/hv.c
new file mode 100644
index 0000000..931b7b0
--- /dev/null
+++ b/drivers/hv/hv.c
@@ -0,0 +1,429 @@
+/*
+ * Copyright (c) 2009, Microsoft Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place - Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * Authors:
+ *   Haiyang Zhang <haiyangz@microsoft.com>
+ *   Hank Janssen  <hjanssen@microsoft.com>
+ *
+ */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+#include <linux/hyperv.h>
+
+#include "hyperv_vmbus.h"
+
+/* The one and only */
+struct hv_context hv_context = {
+	.synic_initialized	= false,
+	.hypercall_page		= NULL,
+	.signal_event_param	= NULL,
+	.signal_event_buffer	= NULL,
+};
+
+/*
+ * query_hypervisor_presence
+ * - Query the cpuid for presence of windows hypervisor
+ */
+static int query_hypervisor_presence(void)
+{
+	unsigned int eax;
+	unsigned int ebx;
+	unsigned int ecx;
+	unsigned int edx;
+	unsigned int op;
+
+	eax = 0;
+	ebx = 0;
+	ecx = 0;
+	edx = 0;
+	op = HVCPUID_VERSION_FEATURES;
+	cpuid(op, &eax, &ebx, &ecx, &edx);
+
+	return ecx & HV_PRESENT_BIT;
+}
+
+/*
+ * query_hypervisor_info - Get version info of the windows hypervisor
+ */
+static int query_hypervisor_info(void)
+{
+	unsigned int eax;
+	unsigned int ebx;
+	unsigned int ecx;
+	unsigned int edx;
+	unsigned int max_leaf;
+	unsigned int op;
+
+	/*
+	* Its assumed that this is called after confirming that Viridian
+	* is present. Query id and revision.
+	*/
+	eax = 0;
+	ebx = 0;
+	ecx = 0;
+	edx = 0;
+	op = HVCPUID_VENDOR_MAXFUNCTION;
+	cpuid(op, &eax, &ebx, &ecx, &edx);
+
+	max_leaf = eax;
+
+	if (max_leaf >= HVCPUID_VERSION) {
+		eax = 0;
+		ebx = 0;
+		ecx = 0;
+		edx = 0;
+		op = HVCPUID_VERSION;
+		cpuid(op, &eax, &ebx, &ecx, &edx);
+		pr_info("Hyper-V Host OS Build:%d-%d.%d-%d-%d.%d\n",
+			    eax,
+			    ebx >> 16,
+			    ebx & 0xFFFF,
+			    ecx,
+			    edx >> 24,
+			    edx & 0xFFFFFF);
+	}
+	return max_leaf;
+}
+
+/*
+ * do_hypercall- Invoke the specified hypercall
+ */
+static u64 do_hypercall(u64 control, void *input, void *output)
+{
+#ifdef CONFIG_X86_64
+	u64 hv_status = 0;
+	u64 input_address = (input) ? virt_to_phys(input) : 0;
+	u64 output_address = (output) ? virt_to_phys(output) : 0;
+	void *hypercall_page = hv_context.hypercall_page;
+
+	__asm__ __volatile__("mov %0, %%r8" : : "r" (output_address) : "r8");
+	__asm__ __volatile__("call *%3" : "=a" (hv_status) :
+			     "c" (control), "d" (input_address),
+			     "m" (hypercall_page));
+
+	return hv_status;
+
+#else
+
+	u32 control_hi = control >> 32;
+	u32 control_lo = control & 0xFFFFFFFF;
+	u32 hv_status_hi = 1;
+	u32 hv_status_lo = 1;
+	u64 input_address = (input) ? virt_to_phys(input) : 0;
+	u32 input_address_hi = input_address >> 32;
+	u32 input_address_lo = input_address & 0xFFFFFFFF;
+	u64 output_address = (output) ? virt_to_phys(output) : 0;
+	u32 output_address_hi = output_address >> 32;
+	u32 output_address_lo = output_address & 0xFFFFFFFF;
+	void *hypercall_page = hv_context.hypercall_page;
+
+	__asm__ __volatile__ ("call *%8" : "=d"(hv_status_hi),
+			      "=a"(hv_status_lo) : "d" (control_hi),
+			      "a" (control_lo), "b" (input_address_hi),
+			      "c" (input_address_lo), "D"(output_address_hi),
+			      "S"(output_address_lo), "m" (hypercall_page));
+
+	return hv_status_lo | ((u64)hv_status_hi << 32);
+#endif /* !x86_64 */
+}
+
+/*
+ * hv_init - Main initialization routine.
+ *
+ * This routine must be called before any other routines in here are called
+ */
+int hv_init(void)
+{
+	int max_leaf;
+	union hv_x64_msr_hypercall_contents hypercall_msr;
+	void *virtaddr = NULL;
+
+	memset(hv_context.synic_event_page, 0, sizeof(void *) * MAX_NUM_CPUS);
+	memset(hv_context.synic_message_page, 0,
+	       sizeof(void *) * MAX_NUM_CPUS);
+
+	if (!query_hypervisor_presence())
+		goto cleanup;
+
+	max_leaf = query_hypervisor_info();
+
+	rdmsrl(HV_X64_MSR_GUEST_OS_ID, hv_context.guestid);
+
+	if (hv_context.guestid != 0)
+		goto cleanup;
+
+	/* Write our OS info */
+	wrmsrl(HV_X64_MSR_GUEST_OS_ID, HV_LINUX_GUEST_ID);
+	hv_context.guestid = HV_LINUX_GUEST_ID;
+
+	/* See if the hypercall page is already set */
+	rdmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
+
+	virtaddr = __vmalloc(PAGE_SIZE, GFP_KERNEL, PAGE_KERNEL_EXEC);
+
+	if (!virtaddr)
+		goto cleanup;
+
+	hypercall_msr.enable = 1;
+
+	hypercall_msr.guest_physical_address = vmalloc_to_pfn(virtaddr);
+	wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
+
+	/* Confirm that hypercall page did get setup. */
+	hypercall_msr.as_uint64 = 0;
+	rdmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
+
+	if (!hypercall_msr.enable)
+		goto cleanup;
+
+	hv_context.hypercall_page = virtaddr;
+
+	/* Setup the global signal event param for the signal event hypercall */
+	hv_context.signal_event_buffer =
+			kmalloc(sizeof(struct hv_input_signal_event_buffer),
+				GFP_KERNEL);
+	if (!hv_context.signal_event_buffer)
+		goto cleanup;
+
+	hv_context.signal_event_param =
+		(struct hv_input_signal_event *)
+			(ALIGN((unsigned long)
+				  hv_context.signal_event_buffer,
+				  HV_HYPERCALL_PARAM_ALIGN));
+	hv_context.signal_event_param->connectionid.asu32 = 0;
+	hv_context.signal_event_param->connectionid.u.id =
+						VMBUS_EVENT_CONNECTION_ID;
+	hv_context.signal_event_param->flag_number = 0;
+	hv_context.signal_event_param->rsvdz = 0;
+
+	return 0;
+
+cleanup:
+	if (virtaddr) {
+		if (hypercall_msr.enable) {
+			hypercall_msr.as_uint64 = 0;
+			wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
+		}
+
+		vfree(virtaddr);
+	}
+
+	return -ENOTSUPP;
+}
+
+/*
+ * hv_cleanup - Cleanup routine.
+ *
+ * This routine is called normally during driver unloading or exiting.
+ */
+void hv_cleanup(void)
+{
+	union hv_x64_msr_hypercall_contents hypercall_msr;
+
+	kfree(hv_context.signal_event_buffer);
+	hv_context.signal_event_buffer = NULL;
+	hv_context.signal_event_param = NULL;
+
+	if (hv_context.hypercall_page) {
+		hypercall_msr.as_uint64 = 0;
+		wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
+		vfree(hv_context.hypercall_page);
+		hv_context.hypercall_page = NULL;
+	}
+}
+
+/*
+ * hv_post_message - Post a message using the hypervisor message IPC.
+ *
+ * This involves a hypercall.
+ */
+u16 hv_post_message(union hv_connection_id connection_id,
+		  enum hv_message_type message_type,
+		  void *payload, size_t payload_size)
+{
+	struct aligned_input {
+		u64 alignment8;
+		struct hv_input_post_message msg;
+	};
+
+	struct hv_input_post_message *aligned_msg;
+	u16 status;
+	unsigned long addr;
+
+	if (payload_size > HV_MESSAGE_PAYLOAD_BYTE_COUNT)
+		return -EMSGSIZE;
+
+	addr = (unsigned long)kmalloc(sizeof(struct aligned_input), GFP_ATOMIC);
+	if (!addr)
+		return -ENOMEM;
+
+	aligned_msg = (struct hv_input_post_message *)
+			(ALIGN(addr, HV_HYPERCALL_PARAM_ALIGN));
+
+	aligned_msg->connectionid = connection_id;
+	aligned_msg->message_type = message_type;
+	aligned_msg->payload_size = payload_size;
+	memcpy((void *)aligned_msg->payload, payload, payload_size);
+
+	status = do_hypercall(HVCALL_POST_MESSAGE, aligned_msg, NULL)
+		& 0xFFFF;
+
+	kfree((void *)addr);
+
+	return status;
+}
+
+
+/*
+ * hv_signal_event -
+ * Signal an event on the specified connection using the hypervisor event IPC.
+ *
+ * This involves a hypercall.
+ */
+u16 hv_signal_event(void)
+{
+	u16 status;
+
+	status = do_hypercall(HVCALL_SIGNAL_EVENT,
+			       hv_context.signal_event_param,
+			       NULL) & 0xFFFF;
+	return status;
+}
+
+/*
+ * hv_synic_init - Initialize the Synthethic Interrupt Controller.
+ *
+ * If it is already initialized by another entity (ie x2v shim), we need to
+ * retrieve the initialized message and event pages.  Otherwise, we create and
+ * initialize the message and event pages.
+ */
+void hv_synic_init(void *irqarg)
+{
+	u64 version;
+	union hv_synic_simp simp;
+	union hv_synic_siefp siefp;
+	union hv_synic_sint shared_sint;
+	union hv_synic_scontrol sctrl;
+
+	u32 irq_vector = *((u32 *)(irqarg));
+	int cpu = smp_processor_id();
+
+	if (!hv_context.hypercall_page)
+		return;
+
+	/* Check the version */
+	rdmsrl(HV_X64_MSR_SVERSION, version);
+
+	hv_context.synic_message_page[cpu] =
+		(void *)get_zeroed_page(GFP_ATOMIC);
+
+	if (hv_context.synic_message_page[cpu] == NULL) {
+		pr_err("Unable to allocate SYNIC message page\n");
+		goto cleanup;
+	}
+
+	hv_context.synic_event_page[cpu] =
+		(void *)get_zeroed_page(GFP_ATOMIC);
+
+	if (hv_context.synic_event_page[cpu] == NULL) {
+		pr_err("Unable to allocate SYNIC event page\n");
+		goto cleanup;
+	}
+
+	/* Setup the Synic's message page */
+	rdmsrl(HV_X64_MSR_SIMP, simp.as_uint64);
+	simp.simp_enabled = 1;
+	simp.base_simp_gpa = virt_to_phys(hv_context.synic_message_page[cpu])
+		>> PAGE_SHIFT;
+
+	wrmsrl(HV_X64_MSR_SIMP, simp.as_uint64);
+
+	/* Setup the Synic's event page */
+	rdmsrl(HV_X64_MSR_SIEFP, siefp.as_uint64);
+	siefp.siefp_enabled = 1;
+	siefp.base_siefp_gpa = virt_to_phys(hv_context.synic_event_page[cpu])
+		>> PAGE_SHIFT;
+
+	wrmsrl(HV_X64_MSR_SIEFP, siefp.as_uint64);
+
+	/* Setup the shared SINT. */
+	rdmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, shared_sint.as_uint64);
+
+	shared_sint.as_uint64 = 0;
+	shared_sint.vector = irq_vector; /* HV_SHARED_SINT_IDT_VECTOR + 0x20; */
+	shared_sint.masked = false;
+	shared_sint.auto_eoi = false;
+
+	wrmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, shared_sint.as_uint64);
+
+	/* Enable the global synic bit */
+	rdmsrl(HV_X64_MSR_SCONTROL, sctrl.as_uint64);
+	sctrl.enable = 1;
+
+	wrmsrl(HV_X64_MSR_SCONTROL, sctrl.as_uint64);
+
+	hv_context.synic_initialized = true;
+	return;
+
+cleanup:
+	if (hv_context.synic_event_page[cpu])
+		free_page((unsigned long)hv_context.synic_event_page[cpu]);
+
+	if (hv_context.synic_message_page[cpu])
+		free_page((unsigned long)hv_context.synic_message_page[cpu]);
+	return;
+}
+
+/*
+ * hv_synic_cleanup - Cleanup routine for hv_synic_init().
+ */
+void hv_synic_cleanup(void *arg)
+{
+	union hv_synic_sint shared_sint;
+	union hv_synic_simp simp;
+	union hv_synic_siefp siefp;
+	int cpu = smp_processor_id();
+
+	if (!hv_context.synic_initialized)
+		return;
+
+	rdmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, shared_sint.as_uint64);
+
+	shared_sint.masked = 1;
+
+	/* Need to correctly cleanup in the case of SMP!!! */
+	/* Disable the interrupt */
+	wrmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, shared_sint.as_uint64);
+
+	rdmsrl(HV_X64_MSR_SIMP, simp.as_uint64);
+	simp.simp_enabled = 0;
+	simp.base_simp_gpa = 0;
+
+	wrmsrl(HV_X64_MSR_SIMP, simp.as_uint64);
+
+	rdmsrl(HV_X64_MSR_SIEFP, siefp.as_uint64);
+	siefp.siefp_enabled = 0;
+	siefp.base_siefp_gpa = 0;
+
+	wrmsrl(HV_X64_MSR_SIEFP, siefp.as_uint64);
+
+	free_page((unsigned long)hv_context.synic_message_page[cpu]);
+	free_page((unsigned long)hv_context.synic_event_page[cpu]);
+}