Merge branch 'akpm' (patches from Andrew)

Merge updates from Andrew Morton:
 "142 patches:

   - DAX updates

   - various misc bits

   - OCFS2 updates

   - most of MM"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (142 commits)
  mm/z3fold.c: limit first_num to the actual range of possible buddy indexes
  mm: fix <linux/pagemap.h> stray kernel-doc notation
  zram: remove obsolete sysfs attrs
  mm/memblock.c: remove unnecessary log and clean up
  oom-reaper: use madvise_dontneed() logic to decide if unmap the VMA
  mm: drop unused argument of zap_page_range()
  mm: drop zap_details::check_swap_entries
  mm: drop zap_details::ignore_dirty
  mm, page_alloc: warn_alloc nodemask is NULL when cpusets are disabled
  mm: help __GFP_NOFAIL allocations which do not trigger OOM killer
  mm, oom: do not enforce OOM killer for __GFP_NOFAIL automatically
  mm: consolidate GFP_NOFAIL checks in the allocator slowpath
  lib/show_mem.c: teach show_mem to work with the given nodemask
  arch, mm: remove arch specific show_mem
  mm, page_alloc: warn_alloc print nodemask
  mm, page_alloc: do not report all nodes in show_mem
  Revert "mm: bail out in shrink_inactive_list()"
  mm, vmscan: consider eligible zones in get_scan_count
  mm, vmscan: cleanup lru size claculations
  mm, vmscan: do not count freed pages as PGDEACTIVATE
  ...

1 files changed, 45 insertions, 13 deletions

diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
index c4889655d32b..7b6a146327d7 100644
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -1138,6 +1138,8 @@ int ocfs2_setattr(struct dentry *dentry, struct iattr *attr)
 	handle_t *handle = NULL;
 	struct dquot *transfer_to[MAXQUOTAS] = { };
 	int qtype;
+	int had_lock;
+	struct ocfs2_lock_holder oh;
 
 	trace_ocfs2_setattr(inode, dentry,
 			    (unsigned long long)OCFS2_I(inode)->ip_blkno,
@@ -1173,11 +1175,30 @@ int ocfs2_setattr(struct dentry *dentry, struct iattr *attr)
 		}
 	}
 
-	status = ocfs2_inode_lock(inode, &bh, 1);
-	if (status < 0) {
-		if (status != -ENOENT)
-			mlog_errno(status);
+	had_lock = ocfs2_inode_lock_tracker(inode, &bh, 1, &oh);
+	if (had_lock < 0) {
+		status = had_lock;
 		goto bail_unlock_rw;
+	} else if (had_lock) {
+		/*
+		 * As far as we know, ocfs2_setattr() could only be the first
+		 * VFS entry point in the call chain of recursive cluster
+		 * locking issue.
+		 *
+		 * For instance:
+		 * chmod_common()
+		 *  notify_change()
+		 *   ocfs2_setattr()
+		 *    posix_acl_chmod()
+		 *     ocfs2_iop_get_acl()
+		 *
+		 * But, we're not 100% sure if it's always true, because the
+		 * ordering of the VFS entry points in the call chain is out
+		 * of our control. So, we'd better dump the stack here to
+		 * catch the other cases of recursive locking.
+		 */
+		mlog(ML_ERROR, "Another case of recursive locking:\n");
+		dump_stack();
 	}
 	inode_locked = 1;
 
@@ -1260,8 +1281,8 @@ int ocfs2_setattr(struct dentry *dentry, struct iattr *attr)
 bail_commit:
 	ocfs2_commit_trans(osb, handle);
 bail_unlock:
-	if (status) {
-		ocfs2_inode_unlock(inode, 1);
+	if (status && inode_locked) {
+		ocfs2_inode_unlock_tracker(inode, 1, &oh, had_lock);
 		inode_locked = 0;
 	}
 bail_unlock_rw:
@@ -1279,7 +1300,7 @@ bail:
 			mlog_errno(status);
 	}
 	if (inode_locked)
-		ocfs2_inode_unlock(inode, 1);
+		ocfs2_inode_unlock_tracker(inode, 1, &oh, had_lock);
 
 	brelse(bh);
 	return status;
@@ -1320,21 +1341,32 @@ bail:
 
 int ocfs2_permission(struct inode *inode, int mask)
 {
-	int ret;
+	int ret, had_lock;
+	struct ocfs2_lock_holder oh;
 
 	if (mask & MAY_NOT_BLOCK)
 		return -ECHILD;
 
-	ret = ocfs2_inode_lock(inode, NULL, 0);
-	if (ret) {
-		if (ret != -ENOENT)
-			mlog_errno(ret);
+	had_lock = ocfs2_inode_lock_tracker(inode, NULL, 0, &oh);
+	if (had_lock < 0) {
+		ret = had_lock;
 		goto out;
+	} else if (had_lock) {
+		/* See comments in ocfs2_setattr() for details.
+		 * The call chain of this case could be:
+		 * do_sys_open()
+		 *  may_open()
+		 *   inode_permission()
+		 *    ocfs2_permission()
+		 *     ocfs2_iop_get_acl()
+		 */
+		mlog(ML_ERROR, "Another case of recursive locking:\n");
+		dump_stack();
 	}
 
 	ret = generic_permission(inode, mask);
 
-	ocfs2_inode_unlock(inode, 0);
+	ocfs2_inode_unlock_tracker(inode, 0, &oh, had_lock);
 out:
 	return ret;
 }