Merge branch 'akpm' (patches from Andrew)

Merge misc fixes from Andrew Morton:
 "Six fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  ocfs2: NFS hangs in __ocfs2_cluster_lock due to race with ocfs2_unblock_lock
  reiserfs: fix dereference of ERR_PTR
  ratelimit: fix bug in time interval by resetting right begin time
  mm: fix kernel crash in khugepaged thread
  mm: fix mlock accouting
  thp: change pmd_trans_huge_lock() interface to return ptl

10 files changed, 54 insertions, 37 deletions

diff --git a/fs/ocfs2/dlmglue.c b/fs/ocfs2/dlmglue.c
index f92612e4b9d6..474e57f834e6 100644
--- a/fs/ocfs2/dlmglue.c
+++ b/fs/ocfs2/dlmglue.c
@@ -1390,6 +1390,7 @@ static int __ocfs2_cluster_lock(struct ocfs2_super *osb,
 	unsigned int gen;
 	int noqueue_attempted = 0;
 	int dlm_locked = 0;
+	int kick_dc = 0;
 
 	if (!(lockres->l_flags & OCFS2_LOCK_INITIALIZED)) {
 		mlog_errno(-EINVAL);
@@ -1524,7 +1525,12 @@ update_holders:
 unlock:
 	lockres_clear_flags(lockres, OCFS2_LOCK_UPCONVERT_FINISHING);
 
+	/* ocfs2_unblock_lock reques on seeing OCFS2_LOCK_UPCONVERT_FINISHING */
+	kick_dc = (lockres->l_flags & OCFS2_LOCK_BLOCKED);
+
 	spin_unlock_irqrestore(&lockres->l_lock, flags);
+	if (kick_dc)
+		ocfs2_wake_downconvert_thread(osb);
 out:
 	/*
 	 * This is helping work around a lock inversion between the page lock
diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index 71ffc91060f6..85d16c67c33e 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -602,7 +602,8 @@ static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
 	pte_t *pte;
 	spinlock_t *ptl;
 
-	if (pmd_trans_huge_lock(pmd, vma, &ptl)) {
+	ptl = pmd_trans_huge_lock(pmd, vma);
+	if (ptl) {
 		smaps_pmd_entry(pmd, addr, walk);
 		spin_unlock(ptl);
 		return 0;
@@ -913,7 +914,8 @@ static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr,
 	spinlock_t *ptl;
 	struct page *page;
 
-	if (pmd_trans_huge_lock(pmd, vma, &ptl)) {
+	ptl = pmd_trans_huge_lock(pmd, vma);
+	if (ptl) {
 		if (cp->type == CLEAR_REFS_SOFT_DIRTY) {
 			clear_soft_dirty_pmd(vma, addr, pmd);
 			goto out;
@@ -1187,7 +1189,8 @@ static int pagemap_pmd_range(pmd_t *pmdp, unsigned long addr, unsigned long end,
 	int err = 0;
 
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
-	if (pmd_trans_huge_lock(pmdp, vma, &ptl)) {
+	ptl = pmd_trans_huge_lock(pmdp, vma);
+	if (ptl) {
 		u64 flags = 0, frame = 0;
 		pmd_t pmd = *pmdp;
 
@@ -1519,7 +1522,8 @@ static int gather_pte_stats(pmd_t *pmd, unsigned long addr,
 	pte_t *orig_pte;
 	pte_t *pte;
 
-	if (pmd_trans_huge_lock(pmd, vma, &ptl)) {
+	ptl = pmd_trans_huge_lock(pmd, vma);
+	if (ptl) {
 		pte_t huge_pte = *(pte_t *)pmd;
 		struct page *page;
 
diff --git a/fs/reiserfs/super.c b/fs/reiserfs/super.c
index 05db7473bcb5..c0306ec8ed7b 100644
--- a/fs/reiserfs/super.c
+++ b/fs/reiserfs/super.c
@@ -288,7 +288,7 @@ static int finish_unfinished(struct super_block *s)
 		pathrelse(&path);
 
 		inode = reiserfs_iget(s, &obj_key);
-		if (!inode) {
+		if (IS_ERR_OR_NULL(inode)) {
 			/*
 			 * the unlink almost completed, it just did not
 			 * manage to remove "save" link and release objectid
diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h
index cfe81e10bd54..459fd25b378e 100644
--- a/include/linux/huge_mm.h
+++ b/include/linux/huge_mm.h
@@ -120,15 +120,15 @@ extern void vma_adjust_trans_huge(struct vm_area_struct *vma,
 				    unsigned long start,
 				    unsigned long end,
 				    long adjust_next);
-extern bool __pmd_trans_huge_lock(pmd_t *pmd, struct vm_area_struct *vma,
-		spinlock_t **ptl);
+extern spinlock_t *__pmd_trans_huge_lock(pmd_t *pmd,
+		struct vm_area_struct *vma);
 /* mmap_sem must be held on entry */
-static inline bool pmd_trans_huge_lock(pmd_t *pmd, struct vm_area_struct *vma,
-		spinlock_t **ptl)
+static inline spinlock_t *pmd_trans_huge_lock(pmd_t *pmd,
+		struct vm_area_struct *vma)
 {
 	VM_BUG_ON_VMA(!rwsem_is_locked(&vma->vm_mm->mmap_sem), vma);
 	if (pmd_trans_huge(*pmd) || pmd_devmap(*pmd))
-		return __pmd_trans_huge_lock(pmd, vma, ptl);
+		return __pmd_trans_huge_lock(pmd, vma);
 	else
 		return false;
 }
@@ -190,10 +190,10 @@ static inline void vma_adjust_trans_huge(struct vm_area_struct *vma,
 					 long adjust_next)
 {
 }
-static inline bool pmd_trans_huge_lock(pmd_t *pmd, struct vm_area_struct *vma,
-		spinlock_t **ptl)
+static inline spinlock_t *pmd_trans_huge_lock(pmd_t *pmd,
+		struct vm_area_struct *vma)
 {
-	return false;
+	return NULL;
 }
 
 static inline int do_huge_pmd_numa_page(struct mm_struct *mm, struct vm_area_struct *vma,
diff --git a/include/trace/events/huge_memory.h b/include/trace/events/huge_memory.h
index 0f803d2783e3..47c6212d8f3c 100644
--- a/include/trace/events/huge_memory.h
+++ b/include/trace/events/huge_memory.h
@@ -46,10 +46,10 @@ SCAN_STATUS
 
 TRACE_EVENT(mm_khugepaged_scan_pmd,
 
-	TP_PROTO(struct mm_struct *mm, unsigned long pfn, bool writable,
+	TP_PROTO(struct mm_struct *mm, struct page *page, bool writable,
 		 bool referenced, int none_or_zero, int status),
 
-	TP_ARGS(mm, pfn, writable, referenced, none_or_zero, status),
+	TP_ARGS(mm, page, writable, referenced, none_or_zero, status),
 
 	TP_STRUCT__entry(
 		__field(struct mm_struct *, mm)
@@ -62,7 +62,7 @@ TRACE_EVENT(mm_khugepaged_scan_pmd,
 
 	TP_fast_assign(
 		__entry->mm = mm;
-		__entry->pfn = pfn;
+		__entry->pfn = page ? page_to_pfn(page) : -1;
 		__entry->writable = writable;
 		__entry->referenced = referenced;
 		__entry->none_or_zero = none_or_zero;
@@ -104,10 +104,10 @@ TRACE_EVENT(mm_collapse_huge_page,
 
 TRACE_EVENT(mm_collapse_huge_page_isolate,
 
-	TP_PROTO(unsigned long pfn, int none_or_zero,
+	TP_PROTO(struct page *page, int none_or_zero,
 		 bool referenced, bool  writable, int status),
 
-	TP_ARGS(pfn, none_or_zero, referenced, writable, status),
+	TP_ARGS(page, none_or_zero, referenced, writable, status),
 
 	TP_STRUCT__entry(
 		__field(unsigned long, pfn)
@@ -118,7 +118,7 @@ TRACE_EVENT(mm_collapse_huge_page_isolate,
 	),
 
 	TP_fast_assign(
-		__entry->pfn = pfn;
+		__entry->pfn = page ? page_to_pfn(page) : -1;
 		__entry->none_or_zero = none_or_zero;
 		__entry->referenced = referenced;
 		__entry->writable = writable;
diff --git a/lib/ratelimit.c b/lib/ratelimit.c
index 40e03ea2a967..2c5de86460c5 100644
--- a/lib/ratelimit.c
+++ b/lib/ratelimit.c
@@ -49,7 +49,7 @@ int ___ratelimit(struct ratelimit_state *rs, const char *func)
 		if (rs->missed)
 			printk(KERN_WARNING "%s: %d callbacks suppressed\n",
 				func, rs->missed);
-		rs->begin   = 0;
+		rs->begin   = jiffies;
 		rs->printed = 0;
 		rs->missed  = 0;
 	}
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 8ad580273521..fd3a07b3e6f4 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -1560,7 +1560,8 @@ int madvise_free_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma,
 	struct mm_struct *mm = tlb->mm;
 	int ret = 0;
 
-	if (!pmd_trans_huge_lock(pmd, vma, &ptl))
+	ptl = pmd_trans_huge_lock(pmd, vma);
+	if (!ptl)
 		goto out_unlocked;
 
 	orig_pmd = *pmd;
@@ -1627,7 +1628,8 @@ int zap_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma,
 	pmd_t orig_pmd;
 	spinlock_t *ptl;
 
-	if (!__pmd_trans_huge_lock(pmd, vma, &ptl))
+	ptl = __pmd_trans_huge_lock(pmd, vma);
+	if (!ptl)
 		return 0;
 	/*
 	 * For architectures like ppc64 we look at deposited pgtable
@@ -1690,7 +1692,8 @@ bool move_huge_pmd(struct vm_area_struct *vma, struct vm_area_struct *new_vma,
 	 * We don't have to worry about the ordering of src and dst
 	 * ptlocks because exclusive mmap_sem prevents deadlock.
 	 */
-	if (__pmd_trans_huge_lock(old_pmd, vma, &old_ptl)) {
+	old_ptl = __pmd_trans_huge_lock(old_pmd, vma);
+	if (old_ptl) {
 		new_ptl = pmd_lockptr(mm, new_pmd);
 		if (new_ptl != old_ptl)
 			spin_lock_nested(new_ptl, SINGLE_DEPTH_NESTING);
@@ -1724,7 +1727,8 @@ int change_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
 	spinlock_t *ptl;
 	int ret = 0;
 
-	if (__pmd_trans_huge_lock(pmd, vma, &ptl)) {
+	ptl = __pmd_trans_huge_lock(pmd, vma);
+	if (ptl) {
 		pmd_t entry;
 		bool preserve_write = prot_numa && pmd_write(*pmd);
 		ret = 1;
@@ -1760,14 +1764,14 @@ int change_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
  * Note that if it returns true, this routine returns without unlocking page
  * table lock. So callers must unlock it.
  */
-bool __pmd_trans_huge_lock(pmd_t *pmd, struct vm_area_struct *vma,
-		spinlock_t **ptl)
+spinlock_t *__pmd_trans_huge_lock(pmd_t *pmd, struct vm_area_struct *vma)
 {
-	*ptl = pmd_lock(vma->vm_mm, pmd);
+	spinlock_t *ptl;
+	ptl = pmd_lock(vma->vm_mm, pmd);
 	if (likely(pmd_trans_huge(*pmd) || pmd_devmap(*pmd)))
-		return true;
-	spin_unlock(*ptl);
-	return false;
+		return ptl;
+	spin_unlock(ptl);
+	return NULL;
 }
 
 #define VM_NO_THP (VM_SPECIAL | VM_HUGETLB | VM_SHARED | VM_MAYSHARE)
@@ -2068,7 +2072,7 @@ static int __collapse_huge_page_isolate(struct vm_area_struct *vma,
 	if (likely(writable)) {
 		if (likely(referenced)) {
 			result = SCAN_SUCCEED;
-			trace_mm_collapse_huge_page_isolate(page_to_pfn(page), none_or_zero,
+			trace_mm_collapse_huge_page_isolate(page, none_or_zero,
 							    referenced, writable, result);
 			return 1;
 		}
@@ -2078,7 +2082,7 @@ static int __collapse_huge_page_isolate(struct vm_area_struct *vma,
 
 out:
 	release_pte_pages(pte, _pte);
-	trace_mm_collapse_huge_page_isolate(page_to_pfn(page), none_or_zero,
+	trace_mm_collapse_huge_page_isolate(page, none_or_zero,
 					    referenced, writable, result);
 	return 0;
 }
@@ -2576,7 +2580,7 @@ out_unmap:
 		collapse_huge_page(mm, address, hpage, vma, node);
 	}
 out:
-	trace_mm_khugepaged_scan_pmd(mm, page_to_pfn(page), writable, referenced,
+	trace_mm_khugepaged_scan_pmd(mm, page, writable, referenced,
 				     none_or_zero, result);
 	return ret;
 }
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index ca052f2a4a0b..d06cae2de783 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -4638,7 +4638,8 @@ static int mem_cgroup_count_precharge_pte_range(pmd_t *pmd,
 	pte_t *pte;
 	spinlock_t *ptl;
 
-	if (pmd_trans_huge_lock(pmd, vma, &ptl)) {
+	ptl = pmd_trans_huge_lock(pmd, vma);
+	if (ptl) {
 		if (get_mctgt_type_thp(vma, addr, *pmd, NULL) == MC_TARGET_PAGE)
 			mc.precharge += HPAGE_PMD_NR;
 		spin_unlock(ptl);
@@ -4826,7 +4827,8 @@ static int mem_cgroup_move_charge_pte_range(pmd_t *pmd,
 	union mc_target target;
 	struct page *page;
 
-	if (pmd_trans_huge_lock(pmd, vma, &ptl)) {
+	ptl = pmd_trans_huge_lock(pmd, vma);
+	if (ptl) {
 		if (mc.precharge < HPAGE_PMD_NR) {
 			spin_unlock(ptl);
 			return 0;
diff --git a/mm/mincore.c b/mm/mincore.c
index 2a565ed8bb49..563f32045490 100644
--- a/mm/mincore.c
+++ b/mm/mincore.c
@@ -117,7 +117,8 @@ static int mincore_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
 	unsigned char *vec = walk->private;
 	int nr = (end - addr) >> PAGE_SHIFT;
 
-	if (pmd_trans_huge_lock(pmd, vma, &ptl)) {
+	ptl = pmd_trans_huge_lock(pmd, vma);
+	if (ptl) {
 		memset(vec, 1, nr);
 		spin_unlock(ptl);
 		goto out;
diff --git a/mm/mlock.c b/mm/mlock.c
index e1e2b1207bf2..96f001041928 100644
--- a/mm/mlock.c
+++ b/mm/mlock.c
@@ -175,7 +175,7 @@ static void __munlock_isolation_failed(struct page *page)
  */
 unsigned int munlock_vma_page(struct page *page)
 {
-	unsigned int nr_pages;
+	int nr_pages;
 	struct zone *zone = page_zone(page);
 
 	/* For try_to_munlock() and to serialize with page migration */