[PATCH v6 02/10] mm/memory_hotplug: add mhp_online_type_to_str() and export string helpers

From: Gregory Price

Date: Tue Jun 30 2026 - 17:22:13 EST


Add mhp_online_type_to_str() as the inverse of mhp_online_type_from_str(),
and export both so a driver can render and parse the memory online type
through its own sysfs interface.

Signed-off-by: Gregory Price <gourry@xxxxxxxxxx>
---
drivers/base/memory.c | 9 +++++++++
include/linux/memory_hotplug.h | 1 +
2 files changed, 10 insertions(+)

diff --git a/drivers/base/memory.c b/drivers/base/memory.c
index b318344426fa..3a2f69d3af7b 100644
--- a/drivers/base/memory.c
+++ b/drivers/base/memory.c
@@ -46,6 +46,15 @@ int mhp_online_type_from_str(const char *str)
}
return -EINVAL;
}
+EXPORT_SYMBOL_GPL(mhp_online_type_from_str);
+
+const char *mhp_online_type_to_str(int online_type)
+{
+ if (online_type < 0 || online_type >= (int)ARRAY_SIZE(online_type_to_str))
+ return NULL;
+ return online_type_to_str[online_type];
+}
+EXPORT_SYMBOL_GPL(mhp_online_type_to_str);

#define to_memory_block(dev) container_of(dev, struct memory_block, dev)

diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h
index 7c9d66729c60..5d4b628c4a1f 100644
--- a/include/linux/memory_hotplug.h
+++ b/include/linux/memory_hotplug.h
@@ -127,6 +127,7 @@ extern int arch_add_memory(int nid, u64 start, u64 size,
extern u64 max_mem_size;

extern int mhp_online_type_from_str(const char *str);
+const char *mhp_online_type_to_str(int online_type);

/* If movable_node boot option specified */
extern bool movable_node_enabled;
--
2.53.0-Meta