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

From: Nuno Das Neves
Date: Fri Nov 20 2020 - 19:31:28 EST

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memory has not been withdrawn.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@xxxxxxxxxxxxx>
Signed-off-by: Lillian Grassin-Drake <ligrassi@xxxxxxxxxxxxx>
Signed-off-by: Nuno Das Neves <nunodasneves@xxxxxxxxxxxxxxxxxxx>
---
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