From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
During ACPI memory hotplug configuration bind memory blocks residing
in modules removable through the standard ACPI mechanism to struct
acpi_device objects associated with ACPI namespace objects
representing those modules. Accordingly, unbind those memory blocks
from the struct acpi_device objects when the memory modules in
question are being removed.
When "offline" operation for devices representing memory blocks is
introduced, this will allow the ACPI core's device hot-remove code to
use it to carry out remove_memory() for those memory blocks and check
the results of that before it actually removes the modules holding
them from the system.
Since walk_memory_range() is used for accessing all memory blocks
corresponding to a given ACPI namespace object, it is exported from
memory_hotplug.c so that the code in acpi_memhotplug.c can use it.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
---
drivers/acpi/acpi_memhotplug.c | 53 ++++++++++++++++++++++++++++++++++++++---
include/linux/memory_hotplug.h | 2 +
mm/memory_hotplug.c | 4 ++-
3 files changed, 55 insertions(+), 4 deletions(-)
Index: linux-pm/mm/memory_hotplug.c
===================================================================
--- linux-pm.orig/mm/memory_hotplug.c
+++ linux-pm/mm/memory_hotplug.c
@@ -1618,6 +1618,7 @@ int offline_pages(unsigned long start_pf
{
return __offline_pages(start_pfn, start_pfn + nr_pages, 120 * HZ);
}
+#endif /* CONFIG_MEMORY_HOTREMOVE */
/**
* walk_memory_range - walks through all mem sections in [start_pfn, end_pfn)
@@ -1631,7 +1632,7 @@ int offline_pages(unsigned long start_pf
*
* Returns the return value of func.
*/
-static int walk_memory_range(unsigned long start_pfn, unsigned long end_pfn,
+int walk_memory_range(unsigned long start_pfn, unsigned long end_pfn,
void *arg, int (*func)(struct memory_block *, void *))
{
struct memory_block *mem = NULL;
@@ -1668,6 +1669,7 @@ static int walk_memory_range(unsigned lo
return 0;
}
+#ifdef CONFIG_MEMORY_HOTREMOVE
/**
* offline_memory_block_cb - callback function for offlining memory block
* @mem: the memory block to be offlined
Index: linux-pm/include/linux/memory_hotplug.h
===================================================================
--- linux-pm.orig/include/linux/memory_hotplug.h
+++ linux-pm/include/linux/memory_hotplug.h
@@ -245,6 +245,8 @@ static inline int is_mem_section_removab
static inline void try_offline_node(int nid) {}
#endif /* CONFIG_MEMORY_HOTREMOVE */
+extern int walk_memory_range(unsigned long start_pfn, unsigned long end_pfn,
+ void *arg, int (*func)(struct memory_block *, void *));
extern int mem_online_node(int nid);
extern int add_memory(int nid, u64 start, u64 size);
extern int arch_add_memory(int nid, u64 start, u64 size);
Index: linux-pm/drivers/acpi/acpi_memhotplug.c
===================================================================
--- linux-pm.orig/drivers/acpi/acpi_memhotplug.c
+++ linux-pm/drivers/acpi/acpi_memhotplug.c
@@ -28,6 +28,7 @@
*/
#include <linux/acpi.h>
+#include <linux/memory.h>
#include <linux/memory_hotplug.h>
#include "internal.h"
@@ -166,13 +167,50 @@ static int acpi_memory_check_device(stru
return 0;
}
+static unsigned long acpi_meminfo_start_pfn(struct acpi_memory_info *info)
+{
+ return PFN_DOWN(info->start_addr);
+}
+
+static unsigned long acpi_meminfo_end_pfn(struct acpi_memory_info *info)
+{
+ return PFN_UP(info->start_addr + info->length-1);
+}
+
+static int acpi_bind_memblk(struct memory_block *mem, void *arg)
+{
+ return acpi_bind_one(&mem->dev, (acpi_handle)arg);
+}
+
+static int acpi_bind_memory_blocks(struct acpi_memory_info *info,
+ acpi_handle handle)
+{
+ return walk_memory_range(acpi_meminfo_start_pfn(info),
+ acpi_meminfo_end_pfn(info), (void *)handle,
+ acpi_bind_memblk);
+}
+
+static int acpi_unbind_memblk(struct memory_block *mem, void *arg)
+{
+ acpi_unbind_one(&mem->dev);
+ return 0;
+}
+
+static void acpi_unbind_memory_blocks(struct acpi_memory_info *info,
+ acpi_handle handle)
+{
+ walk_memory_range(acpi_meminfo_start_pfn(info),
+ acpi_meminfo_end_pfn(info), NULL, acpi_unbind_memblk);
+}
+
static int acpi_memory_enable_device(struct acpi_memory_device *mem_device)
{
+ acpi_handle handle = mem_device->device->handle;
int result, num_enabled = 0;
struct acpi_memory_info *info;
int node;
- node = acpi_get_node(mem_device->device->handle);
+ node = acpi_get_node(handle);
/*
* Tell the VM there is more memory here...
* Note: Assume that this function returns zero on success
@@ -203,6 +241,12 @@ static int acpi_memory_enable_device(str
if (result && result != -EEXIST)
continue;
+ result = acpi_bind_memory_blocks(info, handle);
+ if (result) {
+ acpi_unbind_memory_blocks(info, handle);
+ return -ENODEV;
+ }
+
info->enabled = 1;
/*
@@ -229,10 +273,11 @@ static int acpi_memory_enable_device(str
static int acpi_memory_remove_memory(struct acpi_memory_device *mem_device)
{
+ acpi_handle handle = mem_device->device->handle;
int result = 0, nid;
struct acpi_memory_info *info, *n;
- nid = acpi_get_node(mem_device->device->handle);
+ nid = acpi_get_node(handle);
list_for_each_entry_safe(info, n, &mem_device->res_list, list) {
if (!info->enabled)
@@ -240,6 +285,8 @@ static int acpi_memory_remove_memory(str
if (nid < 0)
nid = memory_add_physaddr_to_nid(info->start_addr);
+
+ acpi_unbind_memory_blocks(info, handle);
result = remove_memory(nid, info->start_addr, info->length);
if (result)
return result;
@@ -300,7 +347,7 @@ static int acpi_memory_device_add(struct
if (result) {
dev_err(&device->dev, "acpi_memory_enable_device() error\n");
acpi_memory_device_free(mem_device);
- return -ENODEV;
+ return result;
}
dev_dbg(&device->dev, "Memory device configured by ACPI\n");
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxx. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>