@@ -137,6 +137,7 @@ int hv_call_deposit_pages(int node, u64 partition_id, u32 num_pages)
 	kfree(counts);
 	return ret;
 }
+EXPORT_SYMBOL_GPL(hv_call_deposit_pages);
 
 int hv_call_add_logical_proc(int node, u32 lp_index, u32 apic_id)
 {

@@ -234,4 +235,5 @@ int hv_call_create_vp(int node, u64 partition_id, u32 vp_index, u32 flags)
 
 	return ret;
 }
+EXPORT_SYMBOL_GPL(hv_call_create_vp);
 

@@ -101,7 +101,7 @@ union hv_partition_processor_features {
 		__u64 fsrep_stosb:1;
 		__u64 fsrep_cmpsb:1;
 		__u64 reserved_bank1:42;
-	};
+	} __packed;
 	__u64 as_uint64[HV_PARTITION_PROCESSOR_FEATURE_BANKS];
 };
 

@@ -111,7 +111,7 @@ union hv_partition_processor_xsave_features {
 		__u64 xsaveopt_support : 1;
 		__u64 avx_support : 1;
 		__u64 reserved1 : 61;
-	};
+	} __packed;
 	__u64 as_uint64;
 };
 

@@ -119,6 +119,6 @@ struct hv_partition_creation_properties {
 	union hv_partition_processor_features disabled_processor_features;
 	union hv_partition_processor_xsave_features
 		disabled_processor_xsave_features;
-};
+} __packed;
 
 #endif

@@ -13,4 +13,4 @@ hv_vmbus-y := vmbus_drv.o \
 hv_vmbus-$(CONFIG_HYPERV_TESTING)	+= hv_debugfs.o
 hv_utils-y := hv_util.o hv_kvp.o hv_snapshot.o hv_fcopy.o hv_utils_transport.o
 
-mshv-y                          += mshv_main.o
+mshv-y                          += mshv_main.o hv_call.o

@@ -0,0 +1,129 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (c) 2021, Microsoft Corporation.
+ *
+ * Authors:
+ *   Nuno Das Neves <nudasnev@microsoft.com>
+ *   Lillian Grassin-Drake <ligrassi@microsoft.com>
+ *   Vineeth Pillai <viremana@linux.microsoft.com>
+ */
+
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <asm/mshyperv.h>
+
+#include "mshv.h"
+
+int hv_call_create_partition(
+		u64 flags,
+		struct hv_partition_creation_properties creation_properties,
+		u64 *partition_id)
+{
+	struct hv_create_partition_in *input;
+	struct hv_create_partition_out *output;
+	u64 status;
+	int ret;
+	unsigned long irq_flags;
+	int i;
+
+	do {
+		local_irq_save(irq_flags);
+		input = (struct hv_create_partition_in *)(*this_cpu_ptr(
+			hyperv_pcpu_input_arg));
+		output = (struct hv_create_partition_out *)(*this_cpu_ptr(
+			hyperv_pcpu_output_arg));
+
+		input->flags = flags;
+		input->proximity_domain_info.as_uint64 = 0;
+		input->compatibility_version = HV_COMPATIBILITY_20_H1;
+		for (i = 0; i < HV_PARTITION_PROCESSOR_FEATURE_BANKS; ++i)
+			input->partition_creation_properties
+				.disabled_processor_features.as_uint64[i] = 0;
+		input->partition_creation_properties
+			.disabled_processor_xsave_features.as_uint64 = 0;
+		input->isolation_properties.as_uint64 = 0;
+
+		status = hv_do_hypercall(HVCALL_CREATE_PARTITION,
+					 input, output);
+
+		if (hv_result(status) != HV_STATUS_INSUFFICIENT_MEMORY) {
+			if (hv_result_success(status))
+				*partition_id = output->partition_id;
+			else
+				pr_err("%s: %s\n",
+				       __func__, hv_status_to_string(status));
+			local_irq_restore(irq_flags);
+			ret = hv_status_to_errno(status);
+			break;
+		}
+		local_irq_restore(irq_flags);
+		ret = hv_call_deposit_pages(NUMA_NO_NODE,
+					    hv_current_partition_id, 1);
+	} while (!ret);
+
+	return ret;
+}
+
+int hv_call_initialize_partition(u64 partition_id)
+{
+	struct hv_initialize_partition input;
+	u64 status;
+	int ret;
+
+	input.partition_id = partition_id;
+
+	ret = hv_call_deposit_pages(
+				NUMA_NO_NODE,
+				partition_id,
+				HV_INIT_PARTITION_DEPOSIT_PAGES);
+	if (ret)
+		return ret;
+
+	do {
+		status = hv_do_fast_hypercall8(
+				HVCALL_INITIALIZE_PARTITION,
+				*(u64*)&input);
+
+		if (hv_result(status) != HV_STATUS_INSUFFICIENT_MEMORY) {
+			if (!hv_result_success(status))
+				pr_err("%s: %s\n",
+				       __func__, hv_status_to_string(status));
+			ret = hv_status_to_errno(status);
+			break;
+		}
+		ret = hv_call_deposit_pages(NUMA_NO_NODE, partition_id, 1);
+	} while (!ret);
+
+	return ret;
+}
+
+int hv_call_finalize_partition(u64 partition_id)
+{
+	struct hv_finalize_partition input;
+	u64 status;
+
+	input.partition_id = partition_id;
+	status = hv_do_fast_hypercall8(
+			HVCALL_FINALIZE_PARTITION,
+			*(u64*)&input);
+
+	if (!hv_result_success(status))
+		pr_err("%s: %s\n", __func__, hv_status_to_string(status));
+
+	return hv_status_to_errno(status);
+}
+
+int hv_call_delete_partition(u64 partition_id)
+{
+	struct hv_delete_partition input;
+	u64 status;
+
+	input.partition_id = partition_id;
+	status = hv_do_fast_hypercall8(HVCALL_DELETE_PARTITION, *(u64*)&input);
+
+	if (!hv_result_success(status))
+		pr_err("%s: %s\n", __func__, hv_status_to_string(status));
+
+	return hv_status_to_errno(status);
+}
+

@@ -0,0 +1,28 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (c) 2021, Microsoft Corporation.
+ *
+ * Authors:
+ *   Nuno Das Neves <nudasnev@microsoft.com>
+ *   Lillian Grassin-Drake <ligrassi@microsoft.com>
+ *   Vineeth Pillai <viremana@linux.microsoft.com>
+ */
+
+#ifndef _MSHV_H_
+#define _MSHV_H_
+
+/* Determined empirically */
+#define HV_INIT_PARTITION_DEPOSIT_PAGES 208
+
+/*
+ * Hyper-V hypercalls
+ */
+int hv_call_create_partition(
+		u64 flags,
+		struct hv_partition_creation_properties creation_properties,
+		u64 *partition_id);
+int hv_call_initialize_partition(u64 partition_id);
+int hv_call_finalize_partition(u64 partition_id);
+int hv_call_delete_partition(u64 partition_id);
+
+#endif /* _MSHV_H */

@@ -15,6 +15,9 @@
 #include <linux/file.h>
 #include <linux/anon_inodes.h>
 #include <linux/mshv.h>
+#include <asm/mshyperv.h>
+
+#include "mshv.h"
 
 MODULE_AUTHOR("Microsoft");
 MODULE_LICENSE("GPL");

@@ -49,6 +52,7 @@ static struct miscdevice mshv_dev = {
 	.mode = 600,
 };
 
+
 static long
 mshv_partition_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
 {

@@ -78,6 +82,17 @@ destroy_partition(struct mshv_partition *partition)
 
 	spin_unlock_irqrestore(&mshv.partitions.lock, flags);
 
+	/*
+	 * There are no remaining references to the partition,
+	 * so the remaining cleanup can be lockless
+	 */
+
+	/* Deallocates and unmaps everything including vcpus, GPA mappings etc */
+	hv_call_finalize_partition(partition->id);
+	/* TODO: Withdraw and free all pages we deposited */
+
+	hv_call_delete_partition(partition->id);
+
 	kfree(partition);
 }
 

@@ -138,6 +153,9 @@ mshv_ioctl_create_partition(void __user *user_arg)
 	if (copy_from_user(&args, user_arg, sizeof(args)))
 		return -EFAULT;
 
+	/* Only support EXO partitions */
+	args.flags |= HV_PARTITION_CREATION_FLAG_EXO_PARTITION;
+
 	partition = kzalloc(sizeof(*partition), GFP_KERNEL);
 	if (!partition)
 		return -ENOMEM;

@@ -148,11 +166,21 @@ mshv_ioctl_create_partition(void __user *user_arg)
 		goto free_partition;
 	}
 
+	ret = hv_call_create_partition(args.flags,
+				       args.partition_creation_properties,
+				       &partition->id);
+	if (ret)
+		goto put_fd;
+
+	ret = hv_call_initialize_partition(partition->id);
+	if (ret)
+		goto delete_partition;
+
 	file = anon_inode_getfile("mshv_partition", &mshv_partition_fops,
 				  partition, O_RDWR);
 	if (IS_ERR(file)) {
 		ret = PTR_ERR(file);
-		goto put_fd;
+		goto finalize_partition;
 	}
 	refcount_set(&partition->ref_count, 1);
 

@@ -166,6 +194,10 @@ mshv_ioctl_create_partition(void __user *user_arg)
 
 release_file:
 	file->f_op->release(file->f_inode, file);
+finalize_partition:
+	hv_call_finalize_partition(partition->id);
+delete_partition:
+	hv_call_delete_partition(partition->id);
 put_fd:
 	put_unused_fd(fd);
 free_partition:

@@ -143,6 +143,10 @@ struct ms_hyperv_tsc_page {
 #define HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX	0x0013
 #define HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX	0x0014
 #define HVCALL_SEND_IPI_EX			0x0015
+#define HVCALL_CREATE_PARTITION			0x0040
+#define HVCALL_INITIALIZE_PARTITION		0x0041
+#define HVCALL_FINALIZE_PARTITION		0x0042
+#define HVCALL_DELETE_PARTITION			0x0043
 #define HVCALL_GET_PARTITION_ID			0x0046
 #define HVCALL_DEPOSIT_MEMORY			0x0048
 #define HVCALL_CREATE_VP			0x004e

@@ -826,4 +830,49 @@ struct hv_memory_hint {
 	union hv_gpa_page_range ranges[];
 } __packed;
 
+union hv_partition_isolation_properties {
+	u64 as_uint64;
+	struct {
+		u64 isolation_type: 5;
+		u64 rsvd_z: 7;
+		u64 shared_gpa_boundary_page_number: 52;
+	};
+} __packed;
+
+/* Non-userspace-visible partition creation flags */
+#define HV_PARTITION_CREATION_FLAG_EXO_PARTITION                    BIT(8)
+
+#define HV_MAKE_COMPATIBILITY_VERSION(major_, minor_)	\
+	((u32)((major_) << 8 | (minor_)))
+
+#define HV_COMPATIBILITY_19_H1		HV_MAKE_COMPATIBILITY_VERSION(0X6, 0X5)
+#define HV_COMPATIBILITY_20_H1		HV_MAKE_COMPATIBILITY_VERSION(0X6, 0X7)
+#define HV_COMPATIBILITY_PRERELEASE	HV_MAKE_COMPATIBILITY_VERSION(0XFE, 0X0)
+#define HV_COMPATIBILITY_EXPERIMENT	HV_MAKE_COMPATIBILITY_VERSION(0XFF, 0X0)
+
+struct hv_create_partition_in {
+	u64 flags;
+	union hv_proximity_domain_info proximity_domain_info;
+	u32 compatibility_version;
+	u32 padding;
+	struct hv_partition_creation_properties partition_creation_properties;
+	union hv_partition_isolation_properties isolation_properties;
+} __packed;
+
+struct hv_create_partition_out {
+	u64 partition_id;
+} __packed;
+
+struct hv_initialize_partition {
+	u64 partition_id;
+} __packed;
+
+struct hv_finalize_partition {
+	u64 partition_id;
+} __packed;
+
+struct hv_delete_partition {
+	u64 partition_id;
+} __packed;
+
 #endif