From: Purna Pavan Chandra Aekkaladevi <paekkaladevi@linux.microsoft.com>
This hypercall can be used to fetch extended properties of a
partition. Extended properties are properties with values larger than
a u64. Some of these also need additional input arguments.
Add helper function for using the hypercall in the mshv_root driver.
Signed-off-by: Purna Pavan Chandra Aekkaladevi <paekkaladevi@linux.microsoft.com>
Signed-off-by: Nuno Das Neves <nunodasneves@linux.microsoft.com>
Reviewed-by: Anirudh Rayabharam <anirudh@anirudhrb.com>
Reviewed-by: Praveen K Paladugu <prapal@linux.microsoft.com>
Reviewed-by: Easwar Hariharan <easwar.hariharan@linux.microsoft.com>
---
drivers/hv/mshv_root.h | 2 ++
drivers/hv/mshv_root_hv_call.c | 31 ++++++++++++++++++++++++++
include/hyperv/hvgdk_mini.h | 1 +
include/hyperv/hvhdk.h | 40 ++++++++++++++++++++++++++++++++++
include/hyperv/hvhdk_mini.h | 26 ++++++++++++++++++++++
5 files changed, 100 insertions(+)
diff --git a/drivers/hv/mshv_root.h b/drivers/hv/mshv_root.h
index e3931b0f1269..4aeb03bea6b6 100644
--- a/drivers/hv/mshv_root.h
+++ b/drivers/hv/mshv_root.h
@@ -303,6 +303,8 @@ int hv_call_unmap_stat_page(enum hv_stats_object_type type,
int hv_call_modify_spa_host_access(u64 partition_id, struct page **pages,
u64 page_struct_count, u32 host_access,
u32 flags, u8 acquire);
+int hv_call_get_partition_property_ex(u64 partition_id, u64 property_code, u64 arg,
+ void *property_value, size_t property_value_sz);
extern struct mshv_root mshv_root;
extern enum hv_scheduler_type hv_scheduler_type;
diff --git a/drivers/hv/mshv_root_hv_call.c b/drivers/hv/mshv_root_hv_call.c
index c9c274f29c3c..3fd3cce23f69 100644
--- a/drivers/hv/mshv_root_hv_call.c
+++ b/drivers/hv/mshv_root_hv_call.c
@@ -590,6 +590,37 @@ int hv_call_unmap_vp_state_page(u64 partition_id, u32 vp_index, u32 type,
return hv_result_to_errno(status);
}
+int hv_call_get_partition_property_ex(u64 partition_id, u64 property_code,
+ u64 arg, void *property_value,
+ size_t property_value_sz)
+{
+ u64 status;
+ unsigned long flags;
+ struct hv_input_get_partition_property_ex *input;
+ struct hv_output_get_partition_property_ex *output;
+
+ local_irq_save(flags);
+ input = *this_cpu_ptr(hyperv_pcpu_input_arg);
+ output = *this_cpu_ptr(hyperv_pcpu_output_arg);
+
+ memset(input, 0, sizeof(*input));
+ input->partition_id = partition_id;
+ input->property_code = property_code;
+ input->arg = arg;
+ status = hv_do_hypercall(HVCALL_GET_PARTITION_PROPERTY_EX, input, output);
+
+ if (!hv_result_success(status)) {
+ hv_status_debug(status, "\n");
+ local_irq_restore(flags);
+ return hv_result_to_errno(status);
+ }
+ memcpy(property_value, &output->property_value, property_value_sz);
+
+ local_irq_restore(flags);
+
+ return 0;
+}
+
int
hv_call_clear_virtual_interrupt(u64 partition_id)
{
diff --git a/include/hyperv/hvgdk_mini.h b/include/hyperv/hvgdk_mini.h
index 1be7f6a02304..ff4325fb623a 100644
--- a/include/hyperv/hvgdk_mini.h
+++ b/include/hyperv/hvgdk_mini.h
@@ -490,6 +490,7 @@ union hv_vp_assist_msr_contents { /* HV_REGISTER_VP_ASSIST_PAGE */
#define HVCALL_GET_VP_STATE 0x00e3
#define HVCALL_SET_VP_STATE 0x00e4
#define HVCALL_GET_VP_CPUID_VALUES 0x00f4
+#define HVCALL_GET_PARTITION_PROPERTY_EX 0x0101
#define HVCALL_MMIO_READ 0x0106
#define HVCALL_MMIO_WRITE 0x0107
diff --git a/include/hyperv/hvhdk.h b/include/hyperv/hvhdk.h
index b4067ada02cf..b91358b9c929 100644
--- a/include/hyperv/hvhdk.h
+++ b/include/hyperv/hvhdk.h
@@ -376,6 +376,46 @@ struct hv_input_set_partition_property {
u64 property_value;
} __packed;
+union hv_partition_property_arg {
+ u64 as_uint64;
+ struct {
+ union {
+ u32 arg;
+ u32 vp_index;
+ };
+ u16 reserved0;
+ u8 reserved1;
+ u8 object_type;
+ };
+} __packed;
+
+struct hv_input_get_partition_property_ex {
+ u64 partition_id;
+ u32 property_code; /* enum hv_partition_property_code */
+ u32 padding;
+ union {
+ union hv_partition_property_arg arg_data;
+ u64 arg;
+ };
+} __packed;
+
+/*
+ * NOTE: Should use hv_input_set_partition_property_ex_header to compute this
+ * size, but hv_input_get_partition_property_ex is identical so it suffices
+ */
+#define HV_PARTITION_PROPERTY_EX_MAX_VAR_SIZE \
+ (HV_HYP_PAGE_SIZE - sizeof(struct hv_input_get_partition_property_ex))
+
+union hv_partition_property_ex {
+ u8 buffer[HV_PARTITION_PROPERTY_EX_MAX_VAR_SIZE];
+ struct hv_partition_property_vmm_capabilities vmm_capabilities;
+ /* More fields to be filled in when needed */
+} __packed;
+
+struct hv_output_get_partition_property_ex {
+ union hv_partition_property_ex property_value;
+} __packed;
+
enum hv_vp_state_page_type {
HV_VP_STATE_PAGE_REGISTERS = 0,
HV_VP_STATE_PAGE_INTERCEPT_MESSAGE = 1,
diff --git a/include/hyperv/hvhdk_mini.h b/include/hyperv/hvhdk_mini.h
index 858f6a3925b3..bf2ce27dfcc5 100644
--- a/include/hyperv/hvhdk_mini.h
+++ b/include/hyperv/hvhdk_mini.h
@@ -96,8 +96,34 @@ enum hv_partition_property_code {
HV_PARTITION_PROPERTY_XSAVE_STATES = 0x00060007,
HV_PARTITION_PROPERTY_MAX_XSAVE_DATA_SIZE = 0x00060008,
HV_PARTITION_PROPERTY_PROCESSOR_CLOCK_FREQUENCY = 0x00060009,
+
+ /* Extended properties with larger property values */
+ HV_PARTITION_PROPERTY_VMM_CAPABILITIES = 0x00090007,
};
+#define HV_PARTITION_VMM_CAPABILITIES_BANK_COUNT 1
+#define HV_PARTITION_VMM_CAPABILITIES_RESERVED_BITFIELD_COUNT 59
+
+struct hv_partition_property_vmm_capabilities {
+ u16 bank_count;
+ u16 reserved[3];
+ union {
+ u64 as_uint64[HV_PARTITION_VMM_CAPABILITIES_BANK_COUNT];
+ struct {
+ u64 map_gpa_preserve_adjustable: 1;
+ u64 vmm_can_provide_overlay_gpfn: 1;
+ u64 vp_affinity_property: 1;
+#if IS_ENABLED(CONFIG_ARM64)
+ u64 vmm_can_provide_gic_overlay_locations: 1;
+#else
+ u64 reservedbit3: 1;
+#endif
+ u64 assignable_synthetic_proc_features: 1;
+ u64 reserved0: HV_PARTITION_VMM_CAPABILITIES_RESERVED_BITFIELD_COUNT;
+ } __packed;
+ };
+} __packed;
+
enum hv_snp_status {
HV_SNP_STATUS_NONE = 0,
HV_SNP_STATUS_AVAILABLE = 1,
--
2.34.1On Tue, Sep 16, 2025 at 04:44:19PM -0700, Nuno Das Neves wrote:
<snip>
> diff --git a/include/hyperv/hvhdk.h b/include/hyperv/hvhdk.h
> index b4067ada02cf..b91358b9c929 100644
> --- a/include/hyperv/hvhdk.h
> +++ b/include/hyperv/hvhdk.h
> @@ -376,6 +376,46 @@ struct hv_input_set_partition_property {
> u64 property_value;
> } __packed;
>
> +union hv_partition_property_arg {
> + u64 as_uint64;
> + struct {
> + union {
> + u32 arg;
> + u32 vp_index;
> + };
> + u16 reserved0;
> + u8 reserved1;
> + u8 object_type;
> + };
> +} __packed;
Shouldn't the struct be "packed" instead?
> +
> +struct hv_input_get_partition_property_ex {
> + u64 partition_id;
> + u32 property_code; /* enum hv_partition_property_code */
> + u32 padding;
> + union {
> + union hv_partition_property_arg arg_data;
> + u64 arg;
> + };
> +} __packed;
> +
> +/*
> + * NOTE: Should use hv_input_set_partition_property_ex_header to compute this
> + * size, but hv_input_get_partition_property_ex is identical so it suffices
> + */
> +#define HV_PARTITION_PROPERTY_EX_MAX_VAR_SIZE \
> + (HV_HYP_PAGE_SIZE - sizeof(struct hv_input_get_partition_property_ex))
> +
> +union hv_partition_property_ex {
> + u8 buffer[HV_PARTITION_PROPERTY_EX_MAX_VAR_SIZE];
> + struct hv_partition_property_vmm_capabilities vmm_capabilities;
> + /* More fields to be filled in when needed */
> +} __packed;
Packing a union is redundant.
Thanks,
Stanislav
On 9/18/2025 11:43 AM, Stanislav Kinsburskii wrote:
> On Tue, Sep 16, 2025 at 04:44:19PM -0700, Nuno Das Neves wrote:
>
> <snip>
>
>> diff --git a/include/hyperv/hvhdk.h b/include/hyperv/hvhdk.h
>> index b4067ada02cf..b91358b9c929 100644
>> --- a/include/hyperv/hvhdk.h
>> +++ b/include/hyperv/hvhdk.h
>> @@ -376,6 +376,46 @@ struct hv_input_set_partition_property {
>> u64 property_value;
>> } __packed;
>>
>> +union hv_partition_property_arg {
>> + u64 as_uint64;
>> + struct {
>> + union {
>> + u32 arg;
>> + u32 vp_index;
>> + };
>> + u16 reserved0;
>> + u8 reserved1;
>> + u8 object_type;
>> + };
>> +} __packed;
>
> Shouldn't the struct be "packed" instead?
>
Indeed, I'll fix it, thanks.
>> +
>> +struct hv_input_get_partition_property_ex {
>> + u64 partition_id;
>> + u32 property_code; /* enum hv_partition_property_code */
>> + u32 padding;
>> + union {
>> + union hv_partition_property_arg arg_data;
>> + u64 arg;
>> + };
>> +} __packed;
>> +
>> +/*
>> + * NOTE: Should use hv_input_set_partition_property_ex_header to compute this
>> + * size, but hv_input_get_partition_property_ex is identical so it suffices
>> + */
>> +#define HV_PARTITION_PROPERTY_EX_MAX_VAR_SIZE \
>> + (HV_HYP_PAGE_SIZE - sizeof(struct hv_input_get_partition_property_ex))
>> +
>> +union hv_partition_property_ex {
>> + u8 buffer[HV_PARTITION_PROPERTY_EX_MAX_VAR_SIZE];
>> + struct hv_partition_property_vmm_capabilities vmm_capabilities;
>> + /* More fields to be filled in when needed */
>> +} __packed;
>
> Packing a union is redundant.
>
> Thanks,
> Stanislav
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