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-rw-r--r--drivers/base/memory.c219
1 files changed, 133 insertions, 86 deletions
diff --git a/drivers/base/memory.c b/drivers/base/memory.c
index f180427e48f4..20c39d1bcef8 100644
--- a/drivers/base/memory.c
+++ b/drivers/base/memory.c
@@ -34,11 +34,21 @@ static DEFINE_MUTEX(mem_sysfs_mutex);
static int sections_per_block;
-static inline int base_memory_block_id(int section_nr)
+static inline unsigned long base_memory_block_id(unsigned long section_nr)
{
return section_nr / sections_per_block;
}
+static inline unsigned long pfn_to_block_id(unsigned long pfn)
+{
+ return base_memory_block_id(pfn_to_section_nr(pfn));
+}
+
+static inline unsigned long phys_to_block_id(unsigned long phys)
+{
+ return pfn_to_block_id(PFN_DOWN(phys));
+}
+
static int memory_subsys_online(struct device *dev);
static int memory_subsys_offline(struct device *dev);
@@ -126,9 +136,9 @@ static ssize_t phys_index_show(struct device *dev,
static ssize_t removable_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
- unsigned long i, pfn;
- int ret = 1;
struct memory_block *mem = to_memory_block(dev);
+ unsigned long pfn;
+ int ret = 1, i;
if (mem->state != MEM_ONLINE)
goto out;
@@ -578,23 +588,13 @@ int __weak arch_get_memory_phys_device(unsigned long start_pfn)
return 0;
}
-/*
- * A reference for the returned object is held and the reference for the
- * hinted object is released.
- */
-struct memory_block *find_memory_block_hinted(struct mem_section *section,
- struct memory_block *hint)
+/* A reference for the returned memory block device is acquired. */
+static struct memory_block *find_memory_block_by_id(unsigned long block_id)
{
- int block_id = base_memory_block_id(__section_nr(section));
- struct device *hintdev = hint ? &hint->dev : NULL;
struct device *dev;
- dev = subsys_find_device_by_id(&memory_subsys, block_id, hintdev);
- if (hint)
- put_device(&hint->dev);
- if (!dev)
- return NULL;
- return to_memory_block(dev);
+ dev = subsys_find_device_by_id(&memory_subsys, block_id, NULL);
+ return dev ? to_memory_block(dev) : NULL;
}
/*
@@ -607,7 +607,9 @@ struct memory_block *find_memory_block_hinted(struct mem_section *section,
*/
struct memory_block *find_memory_block(struct mem_section *section)
{
- return find_memory_block_hinted(section, NULL);
+ unsigned long block_id = base_memory_block_id(__section_nr(section));
+
+ return find_memory_block_by_id(block_id);
}
static struct attribute *memory_memblk_attrs[] = {
@@ -652,20 +654,22 @@ int register_memory(struct memory_block *memory)
}
static int init_memory_block(struct memory_block **memory,
- struct mem_section *section, unsigned long state)
+ unsigned long block_id, unsigned long state)
{
struct memory_block *mem;
unsigned long start_pfn;
- int scn_nr;
int ret = 0;
+ mem = find_memory_block_by_id(block_id);
+ if (mem) {
+ put_device(&mem->dev);
+ return -EEXIST;
+ }
mem = kzalloc(sizeof(*mem), GFP_KERNEL);
if (!mem)
return -ENOMEM;
- scn_nr = __section_nr(section);
- mem->start_section_nr =
- base_memory_block_id(scn_nr) * sections_per_block;
+ mem->start_section_nr = block_id * sections_per_block;
mem->end_section_nr = mem->start_section_nr + sections_per_block - 1;
mem->state = state;
start_pfn = section_nr_to_pfn(mem->start_section_nr);
@@ -677,97 +681,101 @@ static int init_memory_block(struct memory_block **memory,
return ret;
}
-static int add_memory_block(int base_section_nr)
+static int add_memory_block(unsigned long base_section_nr)
{
+ int ret, section_count = 0;
struct memory_block *mem;
- int i, ret, section_count = 0, section_nr;
+ unsigned long nr;
- for (i = base_section_nr;
- i < base_section_nr + sections_per_block;
- i++) {
- if (!present_section_nr(i))
- continue;
- if (section_count == 0)
- section_nr = i;
- section_count++;
- }
+ for (nr = base_section_nr; nr < base_section_nr + sections_per_block;
+ nr++)
+ if (present_section_nr(nr))
+ section_count++;
if (section_count == 0)
return 0;
- ret = init_memory_block(&mem, __nr_to_section(section_nr), MEM_ONLINE);
+ ret = init_memory_block(&mem, base_memory_block_id(base_section_nr),
+ MEM_ONLINE);
if (ret)
return ret;
mem->section_count = section_count;
return 0;
}
+static void unregister_memory(struct memory_block *memory)
+{
+ if (WARN_ON_ONCE(memory->dev.bus != &memory_subsys))
+ return;
+
+ /* drop the ref. we got via find_memory_block() */
+ put_device(&memory->dev);
+ device_unregister(&memory->dev);
+}
+
/*
- * need an interface for the VM to add new memory regions,
- * but without onlining it.
+ * Create memory block devices for the given memory area. Start and size
+ * have to be aligned to memory block granularity. Memory block devices
+ * will be initialized as offline.
*/
-int hotplug_memory_register(int nid, struct mem_section *section)
+int create_memory_block_devices(unsigned long start, unsigned long size)
{
- int ret = 0;
+ const unsigned long start_block_id = pfn_to_block_id(PFN_DOWN(start));
+ unsigned long end_block_id = pfn_to_block_id(PFN_DOWN(start + size));
struct memory_block *mem;
+ unsigned long block_id;
+ int ret = 0;
- mutex_lock(&mem_sysfs_mutex);
+ if (WARN_ON_ONCE(!IS_ALIGNED(start, memory_block_size_bytes()) ||
+ !IS_ALIGNED(size, memory_block_size_bytes())))
+ return -EINVAL;
- mem = find_memory_block(section);
- if (mem) {
- mem->section_count++;
- put_device(&mem->dev);
- } else {
- ret = init_memory_block(&mem, section, MEM_OFFLINE);
+ mutex_lock(&mem_sysfs_mutex);
+ for (block_id = start_block_id; block_id != end_block_id; block_id++) {
+ ret = init_memory_block(&mem, block_id, MEM_OFFLINE);
if (ret)
- goto out;
- mem->section_count++;
+ break;
+ mem->section_count = sections_per_block;
+ }
+ if (ret) {
+ end_block_id = block_id;
+ for (block_id = start_block_id; block_id != end_block_id;
+ block_id++) {
+ mem = find_memory_block_by_id(block_id);
+ mem->section_count = 0;
+ unregister_memory(mem);
+ }
}
-
-out:
mutex_unlock(&mem_sysfs_mutex);
return ret;
}
-#ifdef CONFIG_MEMORY_HOTREMOVE
-static void
-unregister_memory(struct memory_block *memory)
-{
- BUG_ON(memory->dev.bus != &memory_subsys);
-
- /* drop the ref. we got via find_memory_block() */
- put_device(&memory->dev);
- device_unregister(&memory->dev);
-}
-
-void unregister_memory_section(struct mem_section *section)
+/*
+ * Remove memory block devices for the given memory area. Start and size
+ * have to be aligned to memory block granularity. Memory block devices
+ * have to be offline.
+ */
+void remove_memory_block_devices(unsigned long start, unsigned long size)
{
+ const unsigned long start_block_id = pfn_to_block_id(PFN_DOWN(start));
+ const unsigned long end_block_id = pfn_to_block_id(PFN_DOWN(start + size));
struct memory_block *mem;
+ unsigned long block_id;
- if (WARN_ON_ONCE(!present_section(section)))
+ if (WARN_ON_ONCE(!IS_ALIGNED(start, memory_block_size_bytes()) ||
+ !IS_ALIGNED(size, memory_block_size_bytes())))
return;
mutex_lock(&mem_sysfs_mutex);
-
- /*
- * Some users of the memory hotplug do not want/need memblock to
- * track all sections. Skip over those.
- */
- mem = find_memory_block(section);
- if (!mem)
- goto out_unlock;
-
- unregister_mem_sect_under_nodes(mem, __section_nr(section));
-
- mem->section_count--;
- if (mem->section_count == 0)
+ for (block_id = start_block_id; block_id != end_block_id; block_id++) {
+ mem = find_memory_block_by_id(block_id);
+ if (WARN_ON_ONCE(!mem))
+ continue;
+ mem->section_count = 0;
+ unregister_memory_block_under_nodes(mem);
unregister_memory(mem);
- else
- put_device(&mem->dev);
-
-out_unlock:
+ }
mutex_unlock(&mem_sysfs_mutex);
}
-#endif /* CONFIG_MEMORY_HOTREMOVE */
/* return true if the memory block is offlined, otherwise, return false */
bool is_memblock_offlined(struct memory_block *mem)
@@ -804,10 +812,9 @@ static const struct attribute_group *memory_root_attr_groups[] = {
*/
int __init memory_dev_init(void)
{
- unsigned int i;
int ret;
int err;
- unsigned long block_sz;
+ unsigned long block_sz, nr;
ret = subsys_system_register(&memory_subsys, memory_root_attr_groups);
if (ret)
@@ -821,9 +828,9 @@ int __init memory_dev_init(void)
* during boot and have been initialized
*/
mutex_lock(&mem_sysfs_mutex);
- for (i = 0; i <= __highest_present_section_nr;
- i += sections_per_block) {
- err = add_memory_block(i);
+ for (nr = 0; nr <= __highest_present_section_nr;
+ nr += sections_per_block) {
+ err = add_memory_block(nr);
if (!ret)
ret = err;
}
@@ -834,3 +841,43 @@ out:
printk(KERN_ERR "%s() failed: %d\n", __func__, ret);
return ret;
}
+
+/**
+ * walk_memory_blocks - walk through all present memory blocks overlapped
+ * by the range [start, start + size)
+ *
+ * @start: start address of the memory range
+ * @size: size of the memory range
+ * @arg: argument passed to func
+ * @func: callback for each memory section walked
+ *
+ * This function walks through all present memory blocks overlapped by the
+ * range [start, start + size), calling func on each memory block.
+ *
+ * In case func() returns an error, walking is aborted and the error is
+ * returned.
+ */
+int walk_memory_blocks(unsigned long start, unsigned long size,
+ void *arg, walk_memory_blocks_func_t func)
+{
+ const unsigned long start_block_id = phys_to_block_id(start);
+ const unsigned long end_block_id = phys_to_block_id(start + size - 1);
+ struct memory_block *mem;
+ unsigned long block_id;
+ int ret = 0;
+
+ if (!size)
+ return 0;
+
+ for (block_id = start_block_id; block_id <= end_block_id; block_id++) {
+ mem = find_memory_block_by_id(block_id);
+ if (!mem)
+ continue;
+
+ ret = func(mem, arg);
+ put_device(&mem->dev);
+ if (ret)
+ break;
+ }
+ return ret;
+}