2010-12-20 13:56:16

by Daniel Kiper

[permalink] [raw]
Subject: [PATCH 1/3] mm: Add add_registered_memory() to memory hotplug API

add_registered_memory() adds memory ealier registered
as memory resource. It is required by memory hotplug
for Xen guests, however it could be used also by other
modules.

Signed-off-by: Daniel Kiper <[email protected]>
---
include/linux/memory_hotplug.h | 1 +
mm/memory_hotplug.c | 50 ++++++++++++++++++++++++++++++---------
2 files changed, 39 insertions(+), 12 deletions(-)

diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h
index 864035f..2458b2f 100644
--- a/include/linux/memory_hotplug.h
+++ b/include/linux/memory_hotplug.h
@@ -203,6 +203,7 @@ static inline int is_mem_section_removable(unsigned long pfn,
#endif /* CONFIG_MEMORY_HOTREMOVE */

extern int mem_online_node(int nid);
+extern int add_registered_memory(int nid, u64 start, u64 size);
extern int add_memory(int nid, u64 start, u64 size);
extern int arch_add_memory(int nid, u64 start, u64 size);
extern int remove_memory(u64 start, u64 size);
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index dd186c1..b642f26 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -509,20 +509,12 @@ out:
}

/* we are OK calling __meminit stuff here - we have CONFIG_MEMORY_HOTPLUG */
-int __ref add_memory(int nid, u64 start, u64 size)
+static int __ref __add_memory(int nid, u64 start, u64 size)
{
pg_data_t *pgdat = NULL;
int new_pgdat = 0;
- struct resource *res;
int ret;

- lock_system_sleep();
-
- res = register_memory_resource(start, size);
- ret = -EEXIST;
- if (!res)
- goto out;
-
if (!node_online(nid)) {
pgdat = hotadd_new_pgdat(nid, start);
ret = -ENOMEM;
@@ -556,14 +548,48 @@ int __ref add_memory(int nid, u64 start, u64 size)
goto out;

error:
- /* rollback pgdat allocation and others */
+ /* rollback pgdat allocation */
if (new_pgdat)
rollback_node_hotadd(nid, pgdat);
- if (res)
- release_memory_resource(res);
+
+out:
+ return ret;
+}
+
+int add_registered_memory(int nid, u64 start, u64 size)
+{
+ int ret;
+
+ lock_system_sleep();
+ ret = __add_memory(nid, start, size);
+ unlock_system_sleep();
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(add_registered_memory);
+
+int add_memory(int nid, u64 start, u64 size)
+{
+ int ret = -EEXIST;
+ struct resource *res;
+
+ lock_system_sleep();
+
+ res = register_memory_resource(start, size);
+
+ if (!res)
+ goto out;
+
+ ret = __add_memory(nid, start, size);
+
+ if (!ret)
+ goto out;
+
+ release_memory_resource(res);

out:
unlock_system_sleep();
+
return ret;
}
EXPORT_SYMBOL_GPL(add_memory);
--
1.4.4.4