memory-hotplug: add sysfs removable attribute for hotplug memory remove

[karo-tx-linux.git] / drivers / base / memory.c

diff --git a/drivers/base/memory.c b/drivers/base/memory.c
index 7ae413fdd5fc4bd1f0d1b0941316df52dbe8e11f..855ed1a9f97b89d203e0b5f98bd81311c60f1dc4 100644 (file)
--- a/drivers/base/memory.c
+++ b/drivers/base/memory.c
@@ -20,6 +20,7 @@
 #include <linux/kobject.h>
 #include <linux/memory_hotplug.h>
 #include <linux/mm.h>
+#include <linux/mutex.h>
 #include <asm/atomic.h>
 #include <asm/uaccess.h>
 
@@ -52,17 +53,19 @@ int register_memory_notifier(struct notifier_block *nb)
 {
         return blocking_notifier_chain_register(&memory_chain, nb);
 }
+EXPORT_SYMBOL(register_memory_notifier);
 
 void unregister_memory_notifier(struct notifier_block *nb)
 {
         blocking_notifier_chain_unregister(&memory_chain, nb);
 }
+EXPORT_SYMBOL(unregister_memory_notifier);
 
 /*
  * register_memory - Setup a sysfs device for a memory block
  */
-int register_memory(struct memory_block *memory, struct mem_section *section,
-               struct node *root)
+static
+int register_memory(struct memory_block *memory, struct mem_section *section)
 {
        int error;
 
@@ -70,26 +73,18 @@ int register_memory(struct memory_block *memory, struct mem_section *section,
        memory->sysdev.id = __section_nr(section);
 
        error = sysdev_register(&memory->sysdev);
-
-       if (root && !error)
-               error = sysfs_create_link(&root->sysdev.kobj,
-                                         &memory->sysdev.kobj,
-                                         kobject_name(&memory->sysdev.kobj));
-
        return error;
 }
 
 static void
-unregister_memory(struct memory_block *memory, struct mem_section *section,
-               struct node *root)
+unregister_memory(struct memory_block *memory, struct mem_section *section)
 {
        BUG_ON(memory->sysdev.cls != &memory_sysdev_class);
        BUG_ON(memory->sysdev.id != __section_nr(section));
 
+       /* drop the ref. we got in remove_memory_block() */
+       kobject_put(&memory->sysdev.kobj);
        sysdev_unregister(&memory->sysdev);
-       if (root)
-               sysfs_remove_link(&root->sysdev.kobj,
-                                 kobject_name(&memory->sysdev.kobj));
 }
 
 /*
@@ -97,17 +92,34 @@ unregister_memory(struct memory_block *memory, struct mem_section *section,
  * uses.
  */
 
-static ssize_t show_mem_phys_index(struct sys_device *dev, char *buf)
+static ssize_t show_mem_phys_index(struct sys_device *dev,
+                       struct sysdev_attribute *attr, char *buf)
 {
        struct memory_block *mem =
                container_of(dev, struct memory_block, sysdev);
        return sprintf(buf, "%08lx\n", mem->phys_index);
 }
 
+/*
+ * Show whether the section of memory is likely to be hot-removable
+ */
+static ssize_t show_mem_removable(struct sys_device *dev, char *buf)
+{
+       unsigned long start_pfn;
+       int ret;
+       struct memory_block *mem =
+               container_of(dev, struct memory_block, sysdev);
+
+       start_pfn = section_nr_to_pfn(mem->phys_index);
+       ret = is_mem_section_removable(start_pfn, PAGES_PER_SECTION);
+       return sprintf(buf, "%d\n", ret);
+}
+
 /*
  * online, offline, going offline, etc.
  */
-static ssize_t show_mem_state(struct sys_device *dev, char *buf)
+static ssize_t show_mem_state(struct sys_device *dev,
+                       struct sysdev_attribute *attr, char *buf)
 {
        struct memory_block *mem =
                container_of(dev, struct memory_block, sysdev);
@@ -193,7 +205,7 @@ memory_block_action(struct memory_block *mem, unsigned long action)
                        break;
                default:
                        printk(KERN_WARNING "%s(%p, %ld) unknown action: %ld\n",
-                                       __FUNCTION__, mem, action, action);
+                                       __func__, mem, action, action);
                        WARN_ON(1);
                        ret = -EINVAL;
        }
@@ -205,7 +217,7 @@ static int memory_block_change_state(struct memory_block *mem,
                unsigned long to_state, unsigned long from_state_req)
 {
        int ret = 0;
-       down(&mem->state_sem);
+       mutex_lock(&mem->state_mutex);
 
        if (mem->state != from_state_req) {
                ret = -EINVAL;
@@ -217,12 +229,13 @@ static int memory_block_change_state(struct memory_block *mem,
                mem->state = to_state;
 
 out:
-       up(&mem->state_sem);
+       mutex_unlock(&mem->state_mutex);
        return ret;
 }
 
 static ssize_t
-store_mem_state(struct sys_device *dev, const char *buf, size_t count)
+store_mem_state(struct sys_device *dev,
+               struct sysdev_attribute *attr, const char *buf, size_t count)
 {
        struct memory_block *mem;
        unsigned int phys_section_nr;
@@ -253,7 +266,8 @@ out:
  * s.t. if I offline all of these sections I can then
  * remove the physical device?
  */
-static ssize_t show_phys_device(struct sys_device *dev, char *buf)
+static ssize_t show_phys_device(struct sys_device *dev,
+                               struct sysdev_attribute *attr, char *buf)
 {
        struct memory_block *mem =
                container_of(dev, struct memory_block, sysdev);
@@ -263,6 +277,7 @@ static ssize_t show_phys_device(struct sys_device *dev, char *buf)
 static SYSDEV_ATTR(phys_index, 0444, show_mem_phys_index, NULL);
 static SYSDEV_ATTR(state, 0644, show_mem_state, store_mem_state);
 static SYSDEV_ATTR(phys_device, 0444, show_phys_device, NULL);
+static SYSDEV_ATTR(removable, 0444, show_mem_removable, NULL);
 
 #define mem_create_simple_file(mem, attr_name) \
        sysdev_create_file(&mem->sysdev, &attr_##attr_name)
@@ -341,16 +356,18 @@ static int add_memory_block(unsigned long node_id, struct mem_section *section,
 
        mem->phys_index = __section_nr(section);
        mem->state = state;
-       init_MUTEX(&mem->state_sem);
+       mutex_init(&mem->state_mutex);
        mem->phys_device = phys_device;
 
-       ret = register_memory(mem, section, NULL);
+       ret = register_memory(mem, section);
        if (!ret)
                ret = mem_create_simple_file(mem, phys_index);
        if (!ret)
                ret = mem_create_simple_file(mem, state);
        if (!ret)
                ret = mem_create_simple_file(mem, phys_device);
+       if (!ret)
+               ret = mem_create_simple_file(mem, removable);
 
        return ret;
 }
@@ -395,7 +412,8 @@ int remove_memory_block(unsigned long node_id, struct mem_section *section,
        mem_remove_simple_file(mem, phys_index);
        mem_remove_simple_file(mem, state);
        mem_remove_simple_file(mem, phys_device);
-       unregister_memory(mem, section, NULL);
+       mem_remove_simple_file(mem, removable);
+       unregister_memory(mem, section);
 
        return 0;
 }
@@ -451,6 +469,6 @@ int __init memory_dev_init(void)
                ret = err;
 out:
        if (ret)
-               printk(KERN_ERR "%s() failed: %d\n", __FUNCTION__, ret);
+               printk(KERN_ERR "%s() failed: %d\n", __func__, ret);
        return ret;
 }