lift sb_start_write/sb_end_write out of ->aio_write()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/aio.c b/fs/aio.c
index 3f941f2..4ec28f1 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -1324,6 +1324,8 @@
 	if (iocb->ki_pos < 0)
 		return -EINVAL;
 
+	if (opcode == IOCB_CMD_PWRITEV)
+		file_start_write(file);
 	do {
 		ret = rw_op(iocb, &iocb->ki_iovec[iocb->ki_cur_seg],
 			    iocb->ki_nr_segs - iocb->ki_cur_seg,
@@ -1336,6 +1338,8 @@
 	} while (ret > 0 && iocb->ki_left > 0 &&
 		 (opcode == IOCB_CMD_PWRITEV ||
 		  (!S_ISFIFO(inode->i_mode) && !S_ISSOCK(inode->i_mode))));
+	if (opcode == IOCB_CMD_PWRITEV)
+		file_end_write(file);
 
 	/* This means we must have transferred all that we could */
 	/* No need to retry anymore */
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index 5b4ea5f..254aeb7 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -1514,8 +1514,6 @@
 	size_t count, ocount;
 	bool sync = (file->f_flags & O_DSYNC) || IS_SYNC(file->f_mapping->host);
 
-	sb_start_write(inode->i_sb);
-
 	mutex_lock(&inode->i_mutex);
 
 	err = generic_segment_checks(iov, &nr_segs, &ocount, VERIFY_READ);
@@ -1617,7 +1615,6 @@
 	if (sync)
 		atomic_dec(&BTRFS_I(inode)->sync_writers);
 out:
-	sb_end_write(inode->i_sb);
 	current->backing_dev_info = NULL;
 	return num_written ? num_written : err;
 }
diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index 7a0dd99..2d4a231 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -2520,8 +2520,6 @@
 
 	BUG_ON(iocb->ki_pos != pos);
 
-	sb_start_write(inode->i_sb);
-
 	/*
 	 * We need to hold the sem to be sure nobody modifies lock list
 	 * with a brlock that prevents writing.
@@ -2545,7 +2543,6 @@
 	}
 
 	up_read(&cinode->lock_sem);
-	sb_end_write(inode->i_sb);
 	return rc;
 }
 
diff --git a/fs/compat.c b/fs/compat.c
index d487985..daa3b77 100644
--- a/fs/compat.c
+++ b/fs/compat.c
@@ -1103,10 +1103,12 @@
 		fnv = file->f_op->aio_write;
 	}
 
-	if (fnv)
+	if (fnv) {
+		file_start_write(file);
 		ret = do_sync_readv_writev(file, iov, nr_segs, tot_len,
 						pos, fnv);
-	else
+		file_end_write(file);
+	} else
 		ret = do_loop_readv_writev(file, iov, nr_segs, pos, fn);
 
 out:
diff --git a/fs/fuse/file.c b/fs/fuse/file.c
index 34b80ba..d15c6f2 100644
--- a/fs/fuse/file.c
+++ b/fs/fuse/file.c
@@ -971,7 +971,6 @@
 		return err;
 
 	count = ocount;
-	sb_start_write(inode->i_sb);
 	mutex_lock(&inode->i_mutex);
 
 	/* We can write back this queue in page reclaim */
@@ -1030,7 +1029,6 @@
 out:
 	current->backing_dev_info = NULL;
 	mutex_unlock(&inode->i_mutex);
-	sb_end_write(inode->i_sb);
 
 	return written ? written : err;
 }
diff --git a/fs/ntfs/file.c b/fs/ntfs/file.c
index 5b2d4f0..1da4b81 100644
--- a/fs/ntfs/file.c
+++ b/fs/ntfs/file.c
@@ -2129,7 +2129,6 @@
 
 	BUG_ON(iocb->ki_pos != pos);
 
-	sb_start_write(inode->i_sb);
 	mutex_lock(&inode->i_mutex);
 	ret = ntfs_file_aio_write_nolock(iocb, iov, nr_segs, &iocb->ki_pos);
 	mutex_unlock(&inode->i_mutex);
@@ -2138,7 +2137,6 @@
 		if (err < 0)
 			ret = err;
 	}
-	sb_end_write(inode->i_sb);
 	return ret;
 }
 
diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
index 6474cb4..1c93e77 100644
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -2248,8 +2248,6 @@
 	if (iocb->ki_left == 0)
 		return 0;
 
-	sb_start_write(inode->i_sb);
-
 	appending = file->f_flags & O_APPEND ? 1 : 0;
 	direct_io = file->f_flags & O_DIRECT ? 1 : 0;
 
@@ -2423,7 +2421,6 @@
 		ocfs2_iocb_clear_sem_locked(iocb);
 
 	mutex_unlock(&inode->i_mutex);
-	sb_end_write(inode->i_sb);
 
 	if (written)
 		ret = written;
diff --git a/fs/read_write.c b/fs/read_write.c
index f7b5a23..3e1791a 100644
--- a/fs/read_write.c
+++ b/fs/read_write.c
@@ -398,6 +398,7 @@
 	struct kiocb kiocb;
 	ssize_t ret;
 
+	file_start_write(filp);
 	init_sync_kiocb(&kiocb, filp);
 	kiocb.ki_pos = *ppos;
 	kiocb.ki_left = len;
@@ -413,6 +414,7 @@
 	if (-EIOCBQUEUED == ret)
 		ret = wait_on_sync_kiocb(&kiocb);
 	*ppos = kiocb.ki_pos;
+	file_end_write(filp);
 	return ret;
 }
 
@@ -758,10 +760,12 @@
 		fnv = file->f_op->aio_write;
 	}
 
-	if (fnv)
+	if (fnv) {
+		file_start_write(file);
 		ret = do_sync_readv_writev(file, iov, nr_segs, tot_len,
 						pos, fnv);
-	else
+		file_end_write(file);
+	} else
 		ret = do_loop_readv_writev(file, iov, nr_segs, pos, fn);
 
 out:
diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
index f03bf1a..3800128 100644
--- a/fs/xfs/xfs_file.c
+++ b/fs/xfs/xfs_file.c
@@ -775,8 +775,6 @@
 	if (ocount == 0)
 		return 0;
 
-	sb_start_write(inode->i_sb);
-
 	if (XFS_FORCED_SHUTDOWN(ip->i_mount)) {
 		ret = -EIO;
 		goto out;
@@ -800,7 +798,6 @@
 	}
 
 out:
-	sb_end_write(inode->i_sb);
 	return ret;
 }
 
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 2c28271..578a66e 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2223,6 +2223,20 @@
 	return f->f_inode;
 }
 
+static inline void file_start_write(struct file *file)
+{
+	if (!S_ISREG(file_inode(file)->i_mode))
+		return;
+	__sb_start_write(file_inode(file)->i_sb, SB_FREEZE_WRITE, true);
+}
+
+static inline void file_end_write(struct file *file)
+{
+	if (!S_ISREG(file_inode(file)->i_mode))
+		return;
+	__sb_end_write(file_inode(file)->i_sb, SB_FREEZE_WRITE);
+}
+
 /*
  * get_write_access() gets write permission for a file.
  * put_write_access() releases this write permission.
diff --git a/mm/filemap.c b/mm/filemap.c
index e1979fd..cbde884 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -2528,7 +2528,6 @@
 
 	BUG_ON(iocb->ki_pos != pos);
 
-	sb_start_write(inode->i_sb);
 	mutex_lock(&inode->i_mutex);
 	ret = __generic_file_aio_write(iocb, iov, nr_segs, &iocb->ki_pos);
 	mutex_unlock(&inode->i_mutex);
@@ -2540,7 +2539,6 @@
 		if (err < 0 && ret > 0)
 			ret = err;
 	}
-	sb_end_write(inode->i_sb);
 	return ret;
 }
 EXPORT_SYMBOL(generic_file_aio_write);