Merge branch 'akpm' (Andrew's patch-bomb)

Merge patches from Andrew Morton:
 "A few misc things and very nearly all of the MM tree.  A tremendous
  amount of stuff (again), including a significant rbtree library
  rework."

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (160 commits)
  sparc64: Support transparent huge pages.
  mm: thp: Use more portable PMD clearing sequenece in zap_huge_pmd().
  mm: Add and use update_mmu_cache_pmd() in transparent huge page code.
  sparc64: Document PGD and PMD layout.
  sparc64: Eliminate PTE table memory wastage.
  sparc64: Halve the size of PTE tables
  sparc64: Only support 4MB huge pages and 8KB base pages.
  memory-hotplug: suppress "Trying to free nonexistent resource <XXXXXXXXXXXXXXXX-YYYYYYYYYYYYYYYY>" warning
  mm: memcg: clean up mm_match_cgroup() signature
  mm: document PageHuge somewhat
  mm: use %pK for /proc/vmallocinfo
  mm, thp: fix mlock statistics
  mm, thp: fix mapped pages avoiding unevictable list on mlock
  memory-hotplug: update memory block's state and notify userspace
  memory-hotplug: preparation to notify memory block's state at memory hot remove
  mm: avoid section mismatch warning for memblock_type_name
  make GFP_NOTRACK definition unconditional
  cma: decrease cc.nr_migratepages after reclaiming pagelist
  CMA: migrate mlocked pages
  kpageflags: fix wrong KPF_THP on non-huge compound pages
  ...

1 files changed, 30 insertions, 10 deletions

diff --git a/drivers/base/memory.c b/drivers/base/memory.c
index 7dda4f790f00..86c88216a503 100644
--- a/drivers/base/memory.c
+++ b/drivers/base/memory.c
@@ -248,26 +248,23 @@ static bool pages_correctly_reserved(unsigned long start_pfn,
 static int
 memory_block_action(unsigned long phys_index, unsigned long action)
 {
-	unsigned long start_pfn, start_paddr;
+	unsigned long start_pfn;
 	unsigned long nr_pages = PAGES_PER_SECTION * sections_per_block;
 	struct page *first_page;
 	int ret;
 
 	first_page = pfn_to_page(phys_index << PFN_SECTION_SHIFT);
+	start_pfn = page_to_pfn(first_page);
 
 	switch (action) {
 		case MEM_ONLINE:
-			start_pfn = page_to_pfn(first_page);
-
 			if (!pages_correctly_reserved(start_pfn, nr_pages))
 				return -EBUSY;
 
 			ret = online_pages(start_pfn, nr_pages);
 			break;
 		case MEM_OFFLINE:
-			start_paddr = page_to_pfn(first_page) << PAGE_SHIFT;
-			ret = remove_memory(start_paddr,
-					    nr_pages << PAGE_SHIFT);
+			ret = offline_pages(start_pfn, nr_pages);
 			break;
 		default:
 			WARN(1, KERN_WARNING "%s(%ld, %ld) unknown action: "
@@ -278,13 +275,11 @@ memory_block_action(unsigned long phys_index, unsigned long action)
 	return ret;
 }
 
-static int memory_block_change_state(struct memory_block *mem,
+static int __memory_block_change_state(struct memory_block *mem,
 		unsigned long to_state, unsigned long from_state_req)
 {
 	int ret = 0;
 
-	mutex_lock(&mem->state_mutex);
-
 	if (mem->state != from_state_req) {
 		ret = -EINVAL;
 		goto out;
@@ -312,10 +307,20 @@ static int memory_block_change_state(struct memory_block *mem,
 		break;
 	}
 out:
-	mutex_unlock(&mem->state_mutex);
 	return ret;
 }
 
+static int memory_block_change_state(struct memory_block *mem,
+		unsigned long to_state, unsigned long from_state_req)
+{
+	int ret;
+
+	mutex_lock(&mem->state_mutex);
+	ret = __memory_block_change_state(mem, to_state, from_state_req);
+	mutex_unlock(&mem->state_mutex);
+
+	return ret;
+}
 static ssize_t
 store_mem_state(struct device *dev,
 		struct device_attribute *attr, const char *buf, size_t count)
@@ -656,6 +661,21 @@ int unregister_memory_section(struct mem_section *section)
 }
 
 /*
+ * offline one memory block. If the memory block has been offlined, do nothing.
+ */
+int offline_memory_block(struct memory_block *mem)
+{
+	int ret = 0;
+
+	mutex_lock(&mem->state_mutex);
+	if (mem->state != MEM_OFFLINE)
+		ret = __memory_block_change_state(mem, MEM_OFFLINE, MEM_ONLINE);
+	mutex_unlock(&mem->state_mutex);
+
+	return ret;
+}
+
+/*
  * Initialize the sysfs support for memory devices...
  */
 int __init memory_dev_init(void)