Merge tag 'f2fs-fixes-3.16' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs

Pull f2fs bugfixes from Jaegeuk Kim:
 "This includes a couple of bug fixes found by xfstests.  In addition,
  one critical bug was reported by Brian Chadwick, which is falling into
  the infinite loop in balance_dirty_pages.  And it turned out due to
  the IO merging policy in f2fs, which was newly merged in 3.16.

   - fix normal and recovery path for fallocated regions
   - fix error case mishandling
   - recover renamed fsync inodes correctly
   - fix to get out of infinite loops in balance_dirty_pages
   - fix kernel NULL pointer error"

* tag 'f2fs-fixes-3.16' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs:
  f2fs: avoid to access NULL pointer in issue_flush_thread
  f2fs: check bdi->dirty_exceeded when trying to skip data writes
  f2fs: do checkpoint for the renamed inode
  f2fs: release new entry page correctly in error path of f2fs_rename
  f2fs: fix error path in init_inode_metadata
  f2fs: check lower bound nid value in check_nid_range
  f2fs: remove unused variables in f2fs_sm_info
  f2fs: fix not to allocate unnecessary blocks during fallocate
  f2fs: recover fallocated data and its i_size together
  f2fs: fix to report newly allocate region as extent

1 files changed, 8 insertions, 4 deletions

diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index c58e33075719..7d8b96275092 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -659,16 +659,19 @@ static int expand_inode_data(struct inode *inode, loff_t offset,
 	off_start = offset & (PAGE_CACHE_SIZE - 1);
 	off_end = (offset + len) & (PAGE_CACHE_SIZE - 1);
 
+	f2fs_lock_op(sbi);
+
 	for (index = pg_start; index <= pg_end; index++) {
 		struct dnode_of_data dn;
 
-		f2fs_lock_op(sbi);
+		if (index == pg_end && !off_end)
+			goto noalloc;
+
 		set_new_dnode(&dn, inode, NULL, NULL, 0);
 		ret = f2fs_reserve_block(&dn, index);
-		f2fs_unlock_op(sbi);
 		if (ret)
 			break;
-
+noalloc:
 		if (pg_start == pg_end)
 			new_size = offset + len;
 		else if (index == pg_start && off_start)
@@ -683,8 +686,9 @@ static int expand_inode_data(struct inode *inode, loff_t offset,
 		i_size_read(inode) < new_size) {
 		i_size_write(inode, new_size);
 		mark_inode_dirty(inode);
-		f2fs_write_inode(inode, NULL);
+		update_inode_page(inode);
 	}
+	f2fs_unlock_op(sbi);
 
 	return ret;
 }