[RFC PATCH 06/18] virt/mshv: create, initialize, finalize, delete partition hypercalls

[Nuno Das Neves <nunodasneves@linux.microsoft.com>]

Add hypercalls for fully setting up and mostly tearing down a guest
partition.
The teardown operation will generate an error as the deposited
memory has not been withdrawn.
This is fixed in the next patch.

Co-developed-by: Lillian Grassin-Drake <ligrassi@microsoft.com>
Signed-off-by: Lillian Grassin-Drake <ligrassi@microsoft.com>
Signed-off-by: Nuno Das Neves <nunodasneves@linux.microsoft.com>
---
 include/asm-generic/hyperv-tlfs.h      |  52 +++++++-
 include/uapi/asm-generic/hyperv-tlfs.h |   1 +
 include/uapi/linux/mshv.h              |   1 +
 virt/mshv/mshv_main.c                  | 169 ++++++++++++++++++++++++-
 4 files changed, 220 insertions(+), 3 deletions(-)

diff --git a/include/asm-generic/hyperv-tlfs.h b/include/asm-generic/hyperv-tlfs.h
index 2ff580780ce4..ab6ae6c164f5 100644
--- a/include/asm-generic/hyperv-tlfs.h
+++ b/include/asm-generic/hyperv-tlfs.h
@@ -142,6 +142,10 @@ 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
@@ -451,7 +455,7 @@ struct hv_get_partition_id {
 struct hv_deposit_memory {
 	u64 partition_id;
 	u64 gpa_page_list[];
-} __packed;
+};
 
 struct hv_proximity_domain_flags {
 	u32 proximity_preferred : 1;
@@ -767,4 +771,50 @@ struct hv_input_unmap_device_interrupt {
 #define HV_SOURCE_SHADOW_NONE               0x0
 #define HV_SOURCE_SHADOW_BRIDGE_BUS_RANGE   0x1
 
+#define HV_MAKE_COMPATIBILITY_VERSION(major_, minor_)                          \
+	((u32)((major_) << 8 | (minor_)))
+
+enum hv_compatibility_version {
+	HV_COMPATIBILITY_19_H1 = HV_MAKE_COMPATIBILITY_VERSION(0X6, 0X5),
+	HV_COMPATIBILITY_MANGANESE = HV_MAKE_COMPATIBILITY_VERSION(0X6, 0X7),
+	HV_COMPATIBILITY_PRERELEASE = HV_MAKE_COMPATIBILITY_VERSION(0XFE, 0X0),
+	HV_COMPATIBILITY_EXPERIMENT = HV_MAKE_COMPATIBILITY_VERSION(0XFF, 0X0),
+};
+
+union hv_partition_isolation_properties {
+	u64 as_uint64;
+	struct {
+		u64 isolation_type: 5;
+		u64 rsvd_z: 7;
+		u64 shared_gpa_boundary_page_number: 52;
+	};
+};
+
+/* Non-userspace-visible partition creation flags */
+#define HV_PARTITION_CREATION_FLAG_EXO_PARTITION                    BIT(8)
+
+struct hv_create_partition_in {
+	u64 flags;
+	union hv_proximity_domain_info proximity_domain_info;
+	enum hv_compatibility_version compatibility_version;
+	struct hv_partition_creation_properties partition_creation_properties;
+	union hv_partition_isolation_properties isolation_properties;
+};
+
+struct hv_create_partition_out {
+	u64 partition_id;
+};
+
+struct hv_initialize_partition {
+	u64 partition_id;
+};
+
+struct hv_finalize_partition {
+	u64 partition_id;
+};
+
+struct hv_delete_partition {
+	u64 partition_id;
+};
+
 #endif
diff --git a/include/uapi/asm-generic/hyperv-tlfs.h b/include/uapi/asm-generic/hyperv-tlfs.h
index 140cc0b4f98f..7a858226a9c5 100644
--- a/include/uapi/asm-generic/hyperv-tlfs.h
+++ b/include/uapi/asm-generic/hyperv-tlfs.h
@@ -6,6 +6,7 @@
 #define BIT(X)	(1ULL << (X))
 #endif
 
+/* Userspace-visible partition creation flags */
 #define HV_PARTITION_CREATION_FLAG_SMT_ENABLED_GUEST                BIT(0)
 #define HV_PARTITION_CREATION_FLAG_GPA_LARGE_PAGES_DISABLED         BIT(3)
 #define HV_PARTITION_CREATION_FLAG_GPA_SUPER_PAGES_ENABLED          BIT(4)
diff --git a/include/uapi/linux/mshv.h b/include/uapi/linux/mshv.h
index 3788f8bc5caa..4f8da9a6fde2 100644
--- a/include/uapi/linux/mshv.h
+++ b/include/uapi/linux/mshv.h
@@ -9,6 +9,7 @@
 
 #include <linux/types.h>
 #include <asm/hyperv-tlfs.h>
+#include <asm-generic/hyperv-tlfs.h>
 
 #define MSHV_VERSION	0x0
 
diff --git a/virt/mshv/mshv_main.c b/virt/mshv/mshv_main.c
index 4dcbe4907430..c4130a6508e5 100644
--- a/virt/mshv/mshv_main.c
+++ b/virt/mshv/mshv_main.c
@@ -15,6 +15,7 @@
 #include <linux/file.h>
 #include <linux/anon_inodes.h>
 #include <linux/mshv.h>
+#include <asm/mshyperv.h>
 
 MODULE_AUTHOR("Microsoft");
 MODULE_LICENSE("GPL");
@@ -31,7 +32,6 @@ static struct mshv mshv = {};
 static void mshv_partition_put(struct mshv_partition *partition);
 static int mshv_partition_release(struct inode *inode, struct file *filp);
 static long mshv_partition_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg);
-
 static int mshv_dev_open(struct inode *inode, struct file *filp);
 static int mshv_dev_release(struct inode *inode, struct file *filp);
 static long mshv_dev_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg);
@@ -57,6 +57,143 @@ static struct miscdevice mshv_dev = {
 	.mode = 600,
 };
 
+#define HV_INIT_PARTITION_DEPOSIT_PAGES 208
+
+static 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;
+	int 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_MANGANESE;
+		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 (status != HV_STATUS_INSUFFICIENT_MEMORY) {
+			if (status == HV_STATUS_SUCCESS)
+				*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;
+}
+
+static int
+hv_call_initialize_partition(u64 partition_id)
+{
+	struct hv_initialize_partition *input;
+	int status;
+	int ret;
+	unsigned long flags;
+
+	ret = hv_call_deposit_pages(
+				NUMA_NO_NODE,
+				partition_id,
+				HV_INIT_PARTITION_DEPOSIT_PAGES);
+	if (ret)
+		return ret;
+
+	do {
+		local_irq_save(flags);
+		input = (struct hv_initialize_partition *)(*this_cpu_ptr(
+			hyperv_pcpu_input_arg));
+		input->partition_id = partition_id;
+
+		status = hv_do_hypercall(
+				HVCALL_INITIALIZE_PARTITION,
+				input, NULL);
+		local_irq_restore(flags);
+
+		if (status != HV_STATUS_INSUFFICIENT_MEMORY) {
+			if (status != HV_STATUS_SUCCESS)
+				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;
+}
+
+static int
+hv_call_finalize_partition(u64 partition_id)
+{
+	struct hv_finalize_partition *input;
+	int status;
+	unsigned long flags;
+
+	local_irq_save(flags);
+	input = (struct hv_finalize_partition *)(*this_cpu_ptr(
+		hyperv_pcpu_input_arg));
+
+	input->partition_id = partition_id;
+	status = hv_do_hypercall(
+			HVCALL_FINALIZE_PARTITION,
+			input, NULL);
+	local_irq_restore(flags);
+
+	if (status != HV_STATUS_SUCCESS)
+		pr_err("%s: %s\n", __func__, hv_status_to_string(status));
+
+	return -hv_status_to_errno(status);
+}
+
+static int
+hv_call_delete_partition(u64 partition_id)
+{
+	struct hv_delete_partition *input;
+	int status;
+	unsigned long flags;
+
+	local_irq_save(flags);
+	input = (struct hv_delete_partition *)(*this_cpu_ptr(
+		hyperv_pcpu_input_arg));
+
+	input->partition_id = partition_id;
+	status = hv_do_hypercall(
+			HVCALL_DELETE_PARTITION,
+			input, NULL);
+	local_irq_restore(flags);
+
+	if (status != HV_STATUS_SUCCESS)
+		pr_err("%s: %s\n", __func__, hv_status_to_string(status));
+
+	return -hv_status_to_errno(status);
+}
+
 static long
 mshv_partition_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
 {
@@ -86,6 +223,17 @@ destroy_partition(struct mshv_partition *partition)
 
 	spin_unlock_irqrestore(&mshv.partitions.lock, flags);
 
+	/*
+	 * There are no remaining references to the partition or vps,
+	 * 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);
 }
 
@@ -146,6 +294,9 @@ 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;
@@ -156,11 +307,21 @@ 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);
 
@@ -174,6 +335,10 @@ 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:
-- 
2.25.1