Merge tag 'hyperv-next-signed-20250324' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux

Pull hyperv updates from Wei Liu:

 - Add support for running as the root partition in Hyper-V (Microsoft
   Hypervisor) by exposing /dev/mshv (Nuno and various people)

 - Add support for CPU offlining in Hyper-V (Hamza Mahfooz)

 - Misc fixes and cleanups (Roman Kisel, Tianyu Lan, Wei Liu, Michael
   Kelley, Thorsten Blum)

* tag 'hyperv-next-signed-20250324' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux: (24 commits)
  x86/hyperv: fix an indentation issue in mshyperv.h
  x86/hyperv: Add comments about hv_vpset and var size hypercall input args
  Drivers: hv: Introduce mshv_root module to expose /dev/mshv to VMMs
  hyperv: Add definitions for root partition driver to hv headers
  x86: hyperv: Add mshv_handler() irq handler and setup function
  Drivers: hv: Introduce per-cpu event ring tail
  Drivers: hv: Export some functions for use by root partition module
  acpi: numa: Export node_to_pxm()
  hyperv: Introduce hv_recommend_using_aeoi()
  arm64/hyperv: Add some missing functions to arm64
  x86/mshyperv: Add support for extended Hyper-V features
  hyperv: Log hypercall status codes as strings
  x86/hyperv: Fix check of return value from snp_set_vmsa()
  x86/hyperv: Add VTL mode callback for restarting the system
  x86/hyperv: Add VTL mode emergency restart callback
  hyperv: Remove unused union and structs
  hyperv: Add CONFIG_MSHV_ROOT to gate root partition support
  hyperv: Change hv_root_partition into a function
  hyperv: Convert hypercall statuses to linux error codes
  drivers/hv: add CPU offlining support
  ...

1 files changed, 68 insertions, 4 deletions

diff --git a/include/asm-generic/mshyperv.h b/include/asm-generic/mshyperv.h
index a7bbe504e4f3..ccccb1cbf7df 100644
--- a/include/asm-generic/mshyperv.h
+++ b/include/asm-generic/mshyperv.h
@@ -28,9 +28,15 @@
 
 #define VTPM_BASE_ADDRESS 0xfed40000
 
+enum hv_partition_type {
+	HV_PARTITION_TYPE_GUEST,
+	HV_PARTITION_TYPE_ROOT,
+};
+
 struct ms_hyperv_info {
 	u32 features;
 	u32 priv_high;
+	u32 ext_features;
 	u32 misc_features;
 	u32 hints;
 	u32 nested_features;
@@ -58,15 +64,32 @@ struct ms_hyperv_info {
 };
 extern struct ms_hyperv_info ms_hyperv;
 extern bool hv_nested;
+extern u64 hv_current_partition_id;
+extern enum hv_partition_type hv_curr_partition_type;
 
 extern void * __percpu *hyperv_pcpu_input_arg;
 extern void * __percpu *hyperv_pcpu_output_arg;
 
-extern u64 hv_do_hypercall(u64 control, void *inputaddr, void *outputaddr);
-extern u64 hv_do_fast_hypercall8(u16 control, u64 input8);
+u64 hv_do_hypercall(u64 control, void *inputaddr, void *outputaddr);
+u64 hv_do_fast_hypercall8(u16 control, u64 input8);
+u64 hv_do_fast_hypercall16(u16 control, u64 input1, u64 input2);
+
 bool hv_isolation_type_snp(void);
 bool hv_isolation_type_tdx(void);
 
+/*
+ * On architectures where Hyper-V doesn't support AEOI (e.g., ARM64),
+ * it doesn't provide a recommendation flag and AEOI must be disabled.
+ */
+static inline bool hv_recommend_using_aeoi(void)
+{
+#ifdef HV_DEPRECATING_AEOI_RECOMMENDED
+	return !(ms_hyperv.hints & HV_DEPRECATING_AEOI_RECOMMENDED);
+#else
+	return false;
+#endif
+}
+
 static inline struct hv_proximity_domain_info hv_numa_node_to_pxm_info(int node)
 {
 	struct hv_proximity_domain_info pxm_info = {};
@@ -185,12 +208,11 @@ void hv_setup_kexec_handler(void (*handler)(void));
 void hv_remove_kexec_handler(void);
 void hv_setup_crash_handler(void (*handler)(struct pt_regs *regs));
 void hv_remove_crash_handler(void);
+void hv_setup_mshv_handler(void (*handler)(void));
 
 extern int vmbus_interrupt;
 extern int vmbus_irq;
 
-extern bool hv_root_partition;
-
 #if IS_ENABLED(CONFIG_HYPERV)
 /*
  * Hypervisor's notion of virtual processor ID is different from
@@ -207,10 +229,12 @@ extern u64 (*hv_read_reference_counter)(void);
 #define VP_INVAL	U32_MAX
 
 int __init hv_common_init(void);
+void __init hv_get_partition_id(void);
 void __init hv_common_free(void);
 void __init ms_hyperv_late_init(void);
 int hv_common_cpu_init(unsigned int cpu);
 int hv_common_cpu_die(unsigned int cpu);
+void hv_identify_partition_type(void);
 
 void *hv_alloc_hyperv_page(void);
 void *hv_alloc_hyperv_zeroed_page(void);
@@ -291,6 +315,20 @@ static inline int cpumask_to_vpset_skip(struct hv_vpset *vpset,
 	return __cpumask_to_vpset(vpset, cpus, func);
 }
 
+#define _hv_status_fmt(fmt) "%s: Hyper-V status: %#x = %s: " fmt
+#define hv_status_printk(level, status, fmt, ...) \
+do { \
+	u64 __status = (status); \
+	pr_##level(_hv_status_fmt(fmt), __func__, hv_result(__status), \
+		   hv_result_to_string(__status), ##__VA_ARGS__); \
+} while (0)
+#define hv_status_err(status, fmt, ...) \
+	hv_status_printk(err, status, fmt, ##__VA_ARGS__)
+#define hv_status_debug(status, fmt, ...) \
+	hv_status_printk(debug, status, fmt, ##__VA_ARGS__)
+
+const char *hv_result_to_string(u64 hv_status);
+int hv_result_to_errno(u64 status);
 void hyperv_report_panic(struct pt_regs *regs, long err, bool in_die);
 bool hv_is_hyperv_initialized(void);
 bool hv_is_hibernation_supported(void);
@@ -303,6 +341,7 @@ void hyperv_cleanup(void);
 bool hv_query_ext_cap(u64 cap_query);
 void hv_setup_dma_ops(struct device *dev, bool coherent);
 #else /* CONFIG_HYPERV */
+static inline void hv_identify_partition_type(void) {}
 static inline bool hv_is_hyperv_initialized(void) { return false; }
 static inline bool hv_is_hibernation_supported(void) { return false; }
 static inline void hyperv_cleanup(void) {}
@@ -314,4 +353,29 @@ static inline enum hv_isolation_type hv_get_isolation_type(void)
 }
 #endif /* CONFIG_HYPERV */
 
+#if IS_ENABLED(CONFIG_MSHV_ROOT)
+static inline bool hv_root_partition(void)
+{
+	return hv_curr_partition_type == HV_PARTITION_TYPE_ROOT;
+}
+int hv_call_deposit_pages(int node, u64 partition_id, u32 num_pages);
+int hv_call_add_logical_proc(int node, u32 lp_index, u32 acpi_id);
+int hv_call_create_vp(int node, u64 partition_id, u32 vp_index, u32 flags);
+
+#else /* CONFIG_MSHV_ROOT */
+static inline bool hv_root_partition(void) { return false; }
+static inline int hv_call_deposit_pages(int node, u64 partition_id, u32 num_pages)
+{
+	return -EOPNOTSUPP;
+}
+static inline int hv_call_add_logical_proc(int node, u32 lp_index, u32 acpi_id)
+{
+	return -EOPNOTSUPP;
+}
+static inline int hv_call_create_vp(int node, u64 partition_id, u32 vp_index, u32 flags)
+{
+	return -EOPNOTSUPP;
+}
+#endif /* CONFIG_MSHV_ROOT */
+
 #endif