Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull third hunk of vfs changes from Al Viro:
 "This contains the ->direct_IO() changes from Omar + saner
  generic_write_checks() + dealing with fcntl()/{read,write}() races
  (mirroring O_APPEND/O_DIRECT into iocb->ki_flags and instead of
  repeatedly looking at ->f_flags, which can be changed by fcntl(2),
  check ->ki_flags - which cannot) + infrastructure bits for dhowells'
  d_inode annotations + Christophs switch of /dev/loop to
  vfs_iter_write()"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (30 commits)
  block: loop: switch to VFS ITER_BVEC
  configfs: Fix inconsistent use of file_inode() vs file->f_path.dentry->d_inode
  VFS: Make pathwalk use d_is_reg() rather than S_ISREG()
  VFS: Fix up debugfs to use d_is_dir() in place of S_ISDIR()
  VFS: Combine inode checks with d_is_negative() and d_is_positive() in pathwalk
  NFS: Don't use d_inode as a variable name
  VFS: Impose ordering on accesses of d_inode and d_flags
  VFS: Add owner-filesystem positive/negative dentry checks
  nfs: generic_write_checks() shouldn't be done on swapout...
  ocfs2: use __generic_file_write_iter()
  mirror O_APPEND and O_DIRECT into iocb->ki_flags
  switch generic_write_checks() to iocb and iter
  ocfs2: move generic_write_checks() before the alignment checks
  ocfs2_file_write_iter: stop messing with ppos
  udf_file_write_iter: reorder and simplify
  fuse: ->direct_IO() doesn't need generic_write_checks()
  ext4_file_write_iter: move generic_write_checks() up
  xfs_file_aio_write_checks: switch to iocb/iov_iter
  generic_write_checks(): drop isblk argument
  blkdev_write_iter: expand generic_file_checks() call in there
  ...

fs/xfs/xfs_aops.c

@@ -1495,7 +1495,6 @@ xfs_end_io_direct_write(
 
 STATIC ssize_t
 xfs_vm_direct_IO(
-	int			rw,
 	struct kiocb		*iocb,
 	struct iov_iter		*iter,
 	loff_t			offset)
@@ -1503,15 +1502,14 @@ xfs_vm_direct_IO(
 	struct inode		*inode = iocb->ki_filp->f_mapping->host;
 	struct block_device	*bdev = xfs_find_bdev_for_inode(inode);
 
-	if (rw & WRITE) {
-		return __blockdev_direct_IO(rw, iocb, inode, bdev, iter,
-					    offset, xfs_get_blocks_direct,
+	if (iov_iter_rw(iter) == WRITE) {
+		return __blockdev_direct_IO(iocb, inode, bdev, iter, offset,
+					    xfs_get_blocks_direct,
 					    xfs_end_io_direct_write, NULL,
 					    DIO_ASYNC_EXTEND);
 	}
-	return __blockdev_direct_IO(rw, iocb, inode, bdev, iter,
-				    offset, xfs_get_blocks_direct,
-				    NULL, NULL, 0);
+	return __blockdev_direct_IO(iocb, inode, bdev, iter, offset,
+				    xfs_get_blocks_direct, NULL, NULL, 0);
 }
 
 /*

fs/xfs/xfs_file.c

@@ -279,7 +279,7 @@ xfs_file_read_iter(
 
 	XFS_STATS_INC(xs_read_calls);
 
-	if (unlikely(file->f_flags & O_DIRECT))
+	if (unlikely(iocb->ki_flags & IOCB_DIRECT))
 		ioflags |= XFS_IO_ISDIRECT;
 	if (file->f_mode & FMODE_NOCMTIME)
 		ioflags |= XFS_IO_INVIS;
@@ -544,18 +544,19 @@ xfs_zero_eof(
  */
 STATIC ssize_t
 xfs_file_aio_write_checks(
-	struct file		*file,
-	loff_t			*pos,
-	size_t			*count,
+	struct kiocb		*iocb,
+	struct iov_iter		*from,
 	int			*iolock)
 {
+	struct file		*file = iocb->ki_filp;
 	struct inode		*inode = file->f_mapping->host;
 	struct xfs_inode	*ip = XFS_I(inode);
-	int			error = 0;
+	ssize_t			error = 0;
+	size_t			count = iov_iter_count(from);
 
 restart:
-	error = generic_write_checks(file, pos, count, S_ISBLK(inode->i_mode));
-	if (error)
+	error = generic_write_checks(iocb, from);
+	if (error <= 0)
 		return error;
 
 	error = xfs_break_layouts(inode, iolock);
@@ -569,16 +570,17 @@ restart:
 	 * iolock shared, we need to update it to exclusive which implies
 	 * having to redo all checks before.
 	 */
-	if (*pos > i_size_read(inode)) {
+	if (iocb->ki_pos > i_size_read(inode)) {
 		bool	zero = false;
 
 		if (*iolock == XFS_IOLOCK_SHARED) {
 			xfs_rw_iunlock(ip, *iolock);
 			*iolock = XFS_IOLOCK_EXCL;
 			xfs_rw_ilock(ip, *iolock);
+			iov_iter_reexpand(from, count);
 			goto restart;
 		}
-		error = xfs_zero_eof(ip, *pos, i_size_read(inode), &zero);
+		error = xfs_zero_eof(ip, iocb->ki_pos, i_size_read(inode), &zero);
 		if (error)
 			return error;
 	}
@@ -678,10 +680,11 @@ xfs_file_dio_aio_write(
 		xfs_rw_ilock(ip, iolock);
 	}
 
-	ret = xfs_file_aio_write_checks(file, &pos, &count, &iolock);
+	ret = xfs_file_aio_write_checks(iocb, from, &iolock);
 	if (ret)
 		goto out;
-	iov_iter_truncate(from, count);
+	count = iov_iter_count(from);
+	pos = iocb->ki_pos;
 
 	if (mapping->nrpages) {
 		ret = filemap_write_and_wait_range(VFS_I(ip)->i_mapping,
@@ -734,24 +737,22 @@ xfs_file_buffered_aio_write(
 	ssize_t			ret;
 	int			enospc = 0;
 	int			iolock = XFS_IOLOCK_EXCL;
-	loff_t			pos = iocb->ki_pos;
-	size_t			count = iov_iter_count(from);
 
 	xfs_rw_ilock(ip, iolock);
 
-	ret = xfs_file_aio_write_checks(file, &pos, &count, &iolock);
+	ret = xfs_file_aio_write_checks(iocb, from, &iolock);
 	if (ret)
 		goto out;
 
-	iov_iter_truncate(from, count);
 	/* We can write back this queue in page reclaim */
 	current->backing_dev_info = inode_to_bdi(inode);
 
 write_retry:
-	trace_xfs_file_buffered_write(ip, count, iocb->ki_pos, 0);
-	ret = generic_perform_write(file, from, pos);
+	trace_xfs_file_buffered_write(ip, iov_iter_count(from),
+				      iocb->ki_pos, 0);
+	ret = generic_perform_write(file, from, iocb->ki_pos);
 	if (likely(ret >= 0))
-		iocb->ki_pos = pos + ret;
+		iocb->ki_pos += ret;
 
 	/*
 	 * If we hit a space limit, try to free up some lingering preallocated
@@ -803,7 +804,7 @@ xfs_file_write_iter(
 	if (XFS_FORCED_SHUTDOWN(ip->i_mount))
 		return -EIO;
 
-	if (unlikely(file->f_flags & O_DIRECT))
+	if (unlikely(iocb->ki_flags & IOCB_DIRECT))
 		ret = xfs_file_dio_aio_write(iocb, from);
 	else
 		ret = xfs_file_buffered_aio_write(iocb, from);