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authorLinus Torvalds <torvalds@linux-foundation.org>2013-09-03 22:37:15 +0400
committerLinus Torvalds <torvalds@linux-foundation.org>2013-09-03 22:37:15 +0400
commit542a086ac72fb193cbc1b996963a572269e57743 (patch)
treeb137c08037cca4ffc8a156a891a01113b3b8edce /drivers/base/memory.c
parent1d1fdd95df681f0c065d90ffaafa215a0e8825e2 (diff)
parent1eeeef153c02f5856ec109fa532eb5f31c39f85c (diff)
downloadlinux-542a086ac72fb193cbc1b996963a572269e57743.tar.xz
Merge tag 'driver-core-3.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core patches from Greg KH: "Here's the big driver core pull request for 3.12-rc1. Lots of tiny changes here fixing up the way sysfs attributes are created, to try to make drivers simpler, and fix a whole class race conditions with creations of device attributes after the device was announced to userspace. All the various pieces are acked by the different subsystem maintainers" * tag 'driver-core-3.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (119 commits) firmware loader: fix pending_fw_head list corruption drivers/base/memory.c: introduce help macro to_memory_block dynamic debug: line queries failing due to uninitialized local variable sysfs: sysfs_create_groups returns a value. debugfs: provide debugfs_create_x64() when disabled rbd: convert bus code to use bus_groups firmware: dcdbas: use binary attribute groups sysfs: add sysfs_create/remove_groups for when SYSFS is not enabled driver core: add #include <linux/sysfs.h> to core files. HID: convert bus code to use dev_groups Input: serio: convert bus code to use drv_groups Input: gameport: convert bus code to use drv_groups driver core: firmware: use __ATTR_RW() driver core: core: use DEVICE_ATTR_RO driver core: bus: use DRIVER_ATTR_WO() driver core: create write-only attribute macros for devices and drivers sysfs: create __ATTR_WO() driver-core: platform: convert bus code to use dev_groups workqueue: convert bus code to use dev_groups MEI: convert bus code to use dev_groups ...
Diffstat (limited to 'drivers/base/memory.c')
-rw-r--r--drivers/base/memory.c258
1 files changed, 115 insertions, 143 deletions
diff --git a/drivers/base/memory.c b/drivers/base/memory.c
index ec386ee9cb22..1c617623c8ae 100644
--- a/drivers/base/memory.c
+++ b/drivers/base/memory.c
@@ -16,7 +16,6 @@
#include <linux/capability.h>
#include <linux/device.h>
#include <linux/memory.h>
-#include <linux/kobject.h>
#include <linux/memory_hotplug.h>
#include <linux/mm.h>
#include <linux/mutex.h>
@@ -30,6 +29,8 @@ static DEFINE_MUTEX(mem_sysfs_mutex);
#define MEMORY_CLASS_NAME "memory"
+#define to_memory_block(dev) container_of(dev, struct memory_block, dev)
+
static int sections_per_block;
static inline int base_memory_block_id(int section_nr)
@@ -77,7 +78,7 @@ EXPORT_SYMBOL(unregister_memory_isolate_notifier);
static void memory_block_release(struct device *dev)
{
- struct memory_block *mem = container_of(dev, struct memory_block, dev);
+ struct memory_block *mem = to_memory_block(dev);
kfree(mem);
}
@@ -110,8 +111,7 @@ static unsigned long get_memory_block_size(void)
static ssize_t show_mem_start_phys_index(struct device *dev,
struct device_attribute *attr, char *buf)
{
- struct memory_block *mem =
- container_of(dev, struct memory_block, dev);
+ struct memory_block *mem = to_memory_block(dev);
unsigned long phys_index;
phys_index = mem->start_section_nr / sections_per_block;
@@ -121,8 +121,7 @@ static ssize_t show_mem_start_phys_index(struct device *dev,
static ssize_t show_mem_end_phys_index(struct device *dev,
struct device_attribute *attr, char *buf)
{
- struct memory_block *mem =
- container_of(dev, struct memory_block, dev);
+ struct memory_block *mem = to_memory_block(dev);
unsigned long phys_index;
phys_index = mem->end_section_nr / sections_per_block;
@@ -137,8 +136,7 @@ static ssize_t show_mem_removable(struct device *dev,
{
unsigned long i, pfn;
int ret = 1;
- struct memory_block *mem =
- container_of(dev, struct memory_block, dev);
+ struct memory_block *mem = to_memory_block(dev);
for (i = 0; i < sections_per_block; i++) {
if (!present_section_nr(mem->start_section_nr + i))
@@ -156,8 +154,7 @@ static ssize_t show_mem_removable(struct device *dev,
static ssize_t show_mem_state(struct device *dev,
struct device_attribute *attr, char *buf)
{
- struct memory_block *mem =
- container_of(dev, struct memory_block, dev);
+ struct memory_block *mem = to_memory_block(dev);
ssize_t len = 0;
/*
@@ -263,9 +260,8 @@ memory_block_action(unsigned long phys_index, unsigned long action, int online_t
return ret;
}
-static int __memory_block_change_state(struct memory_block *mem,
- unsigned long to_state, unsigned long from_state_req,
- int online_type)
+static int memory_block_change_state(struct memory_block *mem,
+ unsigned long to_state, unsigned long from_state_req)
{
int ret = 0;
@@ -275,105 +271,89 @@ static int __memory_block_change_state(struct memory_block *mem,
if (to_state == MEM_OFFLINE)
mem->state = MEM_GOING_OFFLINE;
- ret = memory_block_action(mem->start_section_nr, to_state, online_type);
+ ret = memory_block_action(mem->start_section_nr, to_state,
+ mem->online_type);
+
mem->state = ret ? from_state_req : to_state;
+
return ret;
}
+/* The device lock serializes operations on memory_subsys_[online|offline] */
static int memory_subsys_online(struct device *dev)
{
- struct memory_block *mem = container_of(dev, struct memory_block, dev);
+ struct memory_block *mem = to_memory_block(dev);
int ret;
- mutex_lock(&mem->state_mutex);
-
- ret = mem->state == MEM_ONLINE ? 0 :
- __memory_block_change_state(mem, MEM_ONLINE, MEM_OFFLINE,
- ONLINE_KEEP);
+ if (mem->state == MEM_ONLINE)
+ return 0;
- mutex_unlock(&mem->state_mutex);
- return ret;
-}
-
-static int memory_subsys_offline(struct device *dev)
-{
- struct memory_block *mem = container_of(dev, struct memory_block, dev);
- int ret;
+ /*
+ * If we are called from store_mem_state(), online_type will be
+ * set >= 0 Otherwise we were called from the device online
+ * attribute and need to set the online_type.
+ */
+ if (mem->online_type < 0)
+ mem->online_type = ONLINE_KEEP;
- mutex_lock(&mem->state_mutex);
+ ret = memory_block_change_state(mem, MEM_ONLINE, MEM_OFFLINE);
- ret = mem->state == MEM_OFFLINE ? 0 :
- __memory_block_change_state(mem, MEM_OFFLINE, MEM_ONLINE, -1);
+ /* clear online_type */
+ mem->online_type = -1;
- mutex_unlock(&mem->state_mutex);
return ret;
}
-static int __memory_block_change_state_uevent(struct memory_block *mem,
- unsigned long to_state, unsigned long from_state_req,
- int online_type)
-{
- int ret = __memory_block_change_state(mem, to_state, from_state_req,
- online_type);
- if (!ret) {
- switch (mem->state) {
- case MEM_OFFLINE:
- kobject_uevent(&mem->dev.kobj, KOBJ_OFFLINE);
- break;
- case MEM_ONLINE:
- kobject_uevent(&mem->dev.kobj, KOBJ_ONLINE);
- break;
- default:
- break;
- }
- }
- return ret;
-}
-
-static int memory_block_change_state(struct memory_block *mem,
- unsigned long to_state, unsigned long from_state_req,
- int online_type)
+static int memory_subsys_offline(struct device *dev)
{
- int ret;
+ struct memory_block *mem = to_memory_block(dev);
- mutex_lock(&mem->state_mutex);
- ret = __memory_block_change_state_uevent(mem, to_state, from_state_req,
- online_type);
- mutex_unlock(&mem->state_mutex);
+ if (mem->state == MEM_OFFLINE)
+ return 0;
- return ret;
+ return memory_block_change_state(mem, MEM_OFFLINE, MEM_ONLINE);
}
+
static ssize_t
store_mem_state(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
- struct memory_block *mem;
- bool offline;
- int ret = -EINVAL;
-
- mem = container_of(dev, struct memory_block, dev);
+ struct memory_block *mem = to_memory_block(dev);
+ int ret, online_type;
lock_device_hotplug();
- if (!strncmp(buf, "online_kernel", min_t(int, count, 13))) {
- offline = false;
- ret = memory_block_change_state(mem, MEM_ONLINE,
- MEM_OFFLINE, ONLINE_KERNEL);
- } else if (!strncmp(buf, "online_movable", min_t(int, count, 14))) {
- offline = false;
- ret = memory_block_change_state(mem, MEM_ONLINE,
- MEM_OFFLINE, ONLINE_MOVABLE);
- } else if (!strncmp(buf, "online", min_t(int, count, 6))) {
- offline = false;
- ret = memory_block_change_state(mem, MEM_ONLINE,
- MEM_OFFLINE, ONLINE_KEEP);
- } else if(!strncmp(buf, "offline", min_t(int, count, 7))) {
- offline = true;
- ret = memory_block_change_state(mem, MEM_OFFLINE,
- MEM_ONLINE, -1);
+ if (!strncmp(buf, "online_kernel", min_t(int, count, 13)))
+ online_type = ONLINE_KERNEL;
+ else if (!strncmp(buf, "online_movable", min_t(int, count, 14)))
+ online_type = ONLINE_MOVABLE;
+ else if (!strncmp(buf, "online", min_t(int, count, 6)))
+ online_type = ONLINE_KEEP;
+ else if (!strncmp(buf, "offline", min_t(int, count, 7)))
+ online_type = -1;
+ else
+ return -EINVAL;
+
+ switch (online_type) {
+ case ONLINE_KERNEL:
+ case ONLINE_MOVABLE:
+ case ONLINE_KEEP:
+ /*
+ * mem->online_type is not protected so there can be a
+ * race here. However, when racing online, the first
+ * will succeed and the second will just return as the
+ * block will already be online. The online type
+ * could be either one, but that is expected.
+ */
+ mem->online_type = online_type;
+ ret = device_online(&mem->dev);
+ break;
+ case -1:
+ ret = device_offline(&mem->dev);
+ break;
+ default:
+ ret = -EINVAL; /* should never happen */
}
- if (!ret)
- dev->offline = offline;
unlock_device_hotplug();
@@ -394,8 +374,7 @@ store_mem_state(struct device *dev,
static ssize_t show_phys_device(struct device *dev,
struct device_attribute *attr, char *buf)
{
- struct memory_block *mem =
- container_of(dev, struct memory_block, dev);
+ struct memory_block *mem = to_memory_block(dev);
return sprintf(buf, "%d\n", mem->phys_device);
}
@@ -471,7 +450,7 @@ store_soft_offline_page(struct device *dev,
u64 pfn;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
- if (strict_strtoull(buf, 0, &pfn) < 0)
+ if (kstrtoull(buf, 0, &pfn) < 0)
return -EINVAL;
pfn >>= PAGE_SHIFT;
if (!pfn_valid(pfn))
@@ -490,7 +469,7 @@ store_hard_offline_page(struct device *dev,
u64 pfn;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
- if (strict_strtoull(buf, 0, &pfn) < 0)
+ if (kstrtoull(buf, 0, &pfn) < 0)
return -EINVAL;
pfn >>= PAGE_SHIFT;
ret = memory_failure(pfn, 0, 0);
@@ -527,7 +506,7 @@ struct memory_block *find_memory_block_hinted(struct mem_section *section,
put_device(&hint->dev);
if (!dev)
return NULL;
- return container_of(dev, struct memory_block, dev);
+ return to_memory_block(dev);
}
/*
@@ -567,16 +546,13 @@ static const struct attribute_group *memory_memblk_attr_groups[] = {
static
int register_memory(struct memory_block *memory)
{
- int error;
-
memory->dev.bus = &memory_subsys;
memory->dev.id = memory->start_section_nr / sections_per_block;
memory->dev.release = memory_block_release;
memory->dev.groups = memory_memblk_attr_groups;
memory->dev.offline = memory->state == MEM_OFFLINE;
- error = device_register(&memory->dev);
- return error;
+ return device_register(&memory->dev);
}
static int init_memory_block(struct memory_block **memory,
@@ -597,7 +573,6 @@ static int init_memory_block(struct memory_block **memory,
mem->end_section_nr = mem->start_section_nr + sections_per_block - 1;
mem->state = state;
mem->section_count++;
- mutex_init(&mem->state_mutex);
start_pfn = section_nr_to_pfn(mem->start_section_nr);
mem->phys_device = arch_get_memory_phys_device(start_pfn);
@@ -607,55 +582,57 @@ static int init_memory_block(struct memory_block **memory,
return ret;
}
-static int add_memory_section(int nid, struct mem_section *section,
- struct memory_block **mem_p,
- unsigned long state, enum mem_add_context context)
+static int add_memory_block(int base_section_nr)
{
- struct memory_block *mem = NULL;
- int scn_nr = __section_nr(section);
- int ret = 0;
-
- mutex_lock(&mem_sysfs_mutex);
-
- if (context == BOOT) {
- /* same memory block ? */
- if (mem_p && *mem_p)
- if (scn_nr >= (*mem_p)->start_section_nr &&
- scn_nr <= (*mem_p)->end_section_nr) {
- mem = *mem_p;
- kobject_get(&mem->dev.kobj);
- }
- } else
- mem = find_memory_block(section);
-
- if (mem) {
- mem->section_count++;
- kobject_put(&mem->dev.kobj);
- } else {
- ret = init_memory_block(&mem, section, state);
- /* store memory_block pointer for next loop */
- if (!ret && context == BOOT)
- if (mem_p)
- *mem_p = mem;
- }
+ struct memory_block *mem;
+ int i, ret, section_count = 0, section_nr;
- if (!ret) {
- if (context == HOTPLUG &&
- mem->section_count == sections_per_block)
- ret = register_mem_sect_under_node(mem, nid);
+ for (i = base_section_nr;
+ (i < base_section_nr + sections_per_block) && i < NR_MEM_SECTIONS;
+ i++) {
+ if (!present_section_nr(i))
+ continue;
+ if (section_count == 0)
+ section_nr = i;
+ section_count++;
}
- mutex_unlock(&mem_sysfs_mutex);
- return ret;
+ if (section_count == 0)
+ return 0;
+ ret = init_memory_block(&mem, __nr_to_section(section_nr), MEM_ONLINE);
+ if (ret)
+ return ret;
+ mem->section_count = section_count;
+ return 0;
}
+
/*
* need an interface for the VM to add new memory regions,
* but without onlining it.
*/
int register_new_memory(int nid, struct mem_section *section)
{
- return add_memory_section(nid, section, NULL, MEM_OFFLINE, HOTPLUG);
+ int ret = 0;
+ struct memory_block *mem;
+
+ mutex_lock(&mem_sysfs_mutex);
+
+ mem = find_memory_block(section);
+ if (mem) {
+ mem->section_count++;
+ put_device(&mem->dev);
+ } else {
+ ret = init_memory_block(&mem, section, MEM_OFFLINE);
+ if (ret)
+ goto out;
+ }
+
+ if (mem->section_count == sections_per_block)
+ ret = register_mem_sect_under_node(mem, nid);
+out:
+ mutex_unlock(&mem_sysfs_mutex);
+ return ret;
}
#ifdef CONFIG_MEMORY_HOTREMOVE
@@ -665,7 +642,7 @@ unregister_memory(struct memory_block *memory)
BUG_ON(memory->dev.bus != &memory_subsys);
/* drop the ref. we got in remove_memory_block() */
- kobject_put(&memory->dev.kobj);
+ put_device(&memory->dev);
device_unregister(&memory->dev);
}
@@ -682,7 +659,7 @@ static int remove_memory_block(unsigned long node_id,
if (mem->section_count == 0)
unregister_memory(mem);
else
- kobject_put(&mem->dev.kobj);
+ put_device(&mem->dev);
mutex_unlock(&mem_sysfs_mutex);
return 0;
@@ -735,7 +712,6 @@ int __init memory_dev_init(void)
int ret;
int err;
unsigned long block_sz;
- struct memory_block *mem = NULL;
ret = subsys_system_register(&memory_subsys, memory_root_attr_groups);
if (ret)
@@ -748,17 +724,13 @@ int __init memory_dev_init(void)
* Create entries for memory sections that were found
* during boot and have been initialized
*/
- for (i = 0; i < NR_MEM_SECTIONS; i++) {
- if (!present_section_nr(i))
- continue;
- /* don't need to reuse memory_block if only one per block */
- err = add_memory_section(0, __nr_to_section(i),
- (sections_per_block == 1) ? NULL : &mem,
- MEM_ONLINE,
- BOOT);
+ mutex_lock(&mem_sysfs_mutex);
+ for (i = 0; i < NR_MEM_SECTIONS; i += sections_per_block) {
+ err = add_memory_block(i);
if (!ret)
ret = err;
}
+ mutex_unlock(&mem_sysfs_mutex);
out:
if (ret)