mshv: Introduce hv_deposit_memory helper functions

Introduce hv_deposit_memory_node() and hv_deposit_memory() helper
functions to handle memory deposit with proper error handling.

The new hv_deposit_memory_node() function takes the hypervisor status
as a parameter and validates it before depositing pages. It checks for
HV_STATUS_INSUFFICIENT_MEMORY specifically and returns an error for
unexpected status codes.

This is a precursor patch to new out-of-memory error codes support.
No functional changes intended.

Signed-off-by: Stanislav Kinsburskii <skinsburskii@linux.microsoft.com>
Reviewed-by: Anirudh Rayabharam (Microsoft) <anirudh@anirudhrb.com>
Reviewed-by: Mukesh R <mrathor@linux.microsoft.com>
Signed-off-by: Wei Liu <wei.liu@kernel.org>

Author: Stanislav Kinsburskii

drivers/hv/hv_proc.c

@@ -110,6 +110,22 @@ int hv_call_deposit_pages(int node, u64 partition_id, u32 num_pages)
 }
 EXPORT_SYMBOL_GPL(hv_call_deposit_pages);
 
+int hv_deposit_memory_node(int node, u64 partition_id,
+			   u64 hv_status)
+{
+	u32 num_pages = 1;
+
+	switch (hv_result(hv_status)) {
+	case HV_STATUS_INSUFFICIENT_MEMORY:
+		break;
+	default:
+		hv_status_err(hv_status, "Unexpected!\n");
+		return -ENOMEM;
+	}
+	return hv_call_deposit_pages(node, partition_id, num_pages);
+}
+EXPORT_SYMBOL_GPL(hv_deposit_memory_node);
+
 bool hv_result_needs_memory(u64 status)
 {
 	switch (hv_result(status)) {
@@ -155,7 +171,8 @@ int hv_call_add_logical_proc(int node, u32 lp_index, u32 apic_id)
 			}
 			break;
 		}
-		ret = hv_call_deposit_pages(node, hv_current_partition_id, 1);
+		ret = hv_deposit_memory_node(node, hv_current_partition_id,
+					     status);
 	} while (!ret);
 
 	return ret;
@@ -197,7 +214,7 @@ int hv_call_create_vp(int node, u64 partition_id, u32 vp_index, u32 flags)
 			}
 			break;
 		}
-		ret = hv_call_deposit_pages(node, partition_id, 1);
+		ret = hv_deposit_memory_node(node, partition_id, status);
 
 	} while (!ret);
 

drivers/hv/mshv_root_hv_call.c

@@ -123,8 +123,7 @@ int hv_call_create_partition(u64 flags,
 			break;
 		}
 		local_irq_restore(irq_flags);
-		ret = hv_call_deposit_pages(NUMA_NO_NODE,
-					    hv_current_partition_id, 1);
+		ret = hv_deposit_memory(hv_current_partition_id, status);
 	} while (!ret);
 
 	return ret;
@@ -151,7 +150,7 @@ int hv_call_initialize_partition(u64 partition_id)
 			ret = hv_result_to_errno(status);
 			break;
 		}
-		ret = hv_call_deposit_pages(NUMA_NO_NODE, partition_id, 1);
+		ret = hv_deposit_memory(partition_id, status);
 	} while (!ret);
 
 	return ret;
@@ -465,8 +464,7 @@ int hv_call_get_vp_state(u32 vp_index, u64 partition_id,
 		}
 		local_irq_restore(flags);
 
-		ret = hv_call_deposit_pages(NUMA_NO_NODE,
-					    partition_id, 1);
+		ret = hv_deposit_memory(partition_id, status);
 	} while (!ret);
 
 	return ret;
@@ -525,8 +523,7 @@ int hv_call_set_vp_state(u32 vp_index, u64 partition_id,
 		}
 		local_irq_restore(flags);
 
-		ret = hv_call_deposit_pages(NUMA_NO_NODE,
-					    partition_id, 1);
+		ret = hv_deposit_memory(partition_id, status);
 	} while (!ret);
 
 	return ret;
@@ -573,7 +570,7 @@ static int hv_call_map_vp_state_page(u64 partition_id, u32 vp_index, u32 type,
 
 		local_irq_restore(flags);
 
-		ret = hv_call_deposit_pages(NUMA_NO_NODE, partition_id, 1);
+		ret = hv_deposit_memory(partition_id, status);
 	} while (!ret);
 
 	return ret;
@@ -722,8 +719,7 @@ hv_call_create_port(u64 port_partition_id, union hv_port_id port_id,
 			ret = hv_result_to_errno(status);
 			break;
 		}
-		ret = hv_call_deposit_pages(NUMA_NO_NODE, port_partition_id, 1);
-
+		ret = hv_deposit_memory(port_partition_id, status);
 	} while (!ret);
 
 	return ret;
@@ -776,8 +772,7 @@ hv_call_connect_port(u64 port_partition_id, union hv_port_id port_id,
 			ret = hv_result_to_errno(status);
 			break;
 		}
-		ret = hv_call_deposit_pages(NUMA_NO_NODE,
-					    connection_partition_id, 1);
+		ret = hv_deposit_memory(connection_partition_id, status);
 	} while (!ret);
 
 	return ret;
@@ -855,8 +850,7 @@ static int hv_call_map_stats_page2(enum hv_stats_object_type type,
 			break;
 		}
 
-		ret = hv_call_deposit_pages(NUMA_NO_NODE,
-					    hv_current_partition_id, 1);
+		ret = hv_deposit_memory(hv_current_partition_id, status);
 	} while (!ret);
 
 	return ret;
@@ -929,8 +923,7 @@ hv_call_map_stats_page(enum hv_stats_object_type type,
 			return hv_result_to_errno(status);
 		}
 
-		ret = hv_call_deposit_pages(NUMA_NO_NODE,
-					    hv_current_partition_id, 1);
+		ret = hv_deposit_memory(hv_current_partition_id, status);
 		if (ret)
 			return ret;
 	} while (!ret);

drivers/hv/mshv_root_main.c

@@ -255,8 +255,7 @@ static int mshv_ioctl_passthru_hvcall(struct mshv_partition *partition,
 		if (!hv_result_needs_memory(status))
 			ret = hv_result_to_errno(status);
 		else
-			ret = hv_call_deposit_pages(NUMA_NO_NODE,
-						    pt_id, 1);
+			ret = hv_deposit_memory(pt_id, status);
 	} while (!ret);
 
 	args.status = hv_result(status);

include/asm-generic/mshyperv.h

@@ -344,6 +344,7 @@ static inline bool hv_parent_partition(void)
 }
 
 bool hv_result_needs_memory(u64 status);
+int hv_deposit_memory_node(int node, u64 partition_id, u64 status);
 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);
@@ -353,6 +354,10 @@ static inline bool hv_root_partition(void) { return false; }
 static inline bool hv_l1vh_partition(void) { return false; }
 static inline bool hv_parent_partition(void) { return false; }
 static inline bool hv_result_needs_memory(u64 status) { return false; }
+static inline int hv_deposit_memory_node(int node, u64 partition_id, u64 status)
+{
+	return -EOPNOTSUPP;
+}
 static inline int hv_call_deposit_pages(int node, u64 partition_id, u32 num_pages)
 {
 	return -EOPNOTSUPP;
@@ -367,6 +372,11 @@ static inline int hv_call_create_vp(int node, u64 partition_id, u32 vp_index, u3
 }
 #endif /* CONFIG_MSHV_ROOT */
 
+static inline int hv_deposit_memory(u64 partition_id, u64 status)
+{
+	return hv_deposit_memory_node(NUMA_NO_NODE, partition_id, status);
+}
+
 #if IS_ENABLED(CONFIG_HYPERV_VTL_MODE)
 u8 __init get_vtl(void);
 #else