Commit 304e45ac authored by Stefan Roesch's avatar Stefan Roesch Committed by David Sterba
Browse files

btrfs: plumb NOWAIT through the write path 



We have everywhere setup for nowait, plumb NOWAIT through the write path.

Reviewed-by: default avatarFilipe Manana <fdmanana@suse.com>
Signed-off-by: default avatarJosef Bacik <josef@toxicpanda.com>
Signed-off-by: default avatarStefan Roesch <shr@fb.com>
Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent 2fcab928

fs/btrfs/file.c

+13 −6
Original line number Diff line number Diff line
@@ -1652,8 +1652,9 @@ static noinline ssize_t btrfs_buffered_write(struct kiocb *iocb, 
	bool force_page_uptodate = false;

	loff_t old_isize = i_size_read(inode);

	unsigned int ilock_flags = 0;

	const bool nowait = (iocb->ki_flags & IOCB_NOWAIT);



	if (iocb->ki_flags & IOCB_NOWAIT)

	if (nowait)

		ilock_flags |= BTRFS_ILOCK_TRY;



	ret = btrfs_inode_lock(inode, ilock_flags);
@@ -1709,17 +1710,22 @@ static noinline ssize_t btrfs_buffered_write(struct kiocb *iocb, 
		extent_changeset_release(data_reserved);

		ret = btrfs_check_data_free_space(BTRFS_I(inode),

						  &data_reserved, pos,

						  write_bytes, false);

						  write_bytes, nowait);

		if (ret < 0) {

			int can_nocow;



			if (nowait && (ret == -ENOSPC || ret == -EAGAIN)) {

				ret = -EAGAIN;

				break;

			}



			/*

			 * If we don't have to COW at the offset, reserve

			 * metadata only. write_bytes may get smaller than

			 * requested here.

			 */

			can_nocow = btrfs_check_nocow_lock(BTRFS_I(inode), pos,

							   &write_bytes, false);

							   &write_bytes, nowait);

			if (can_nocow < 0)

				ret = can_nocow;

			if (can_nocow > 0)
@@ -1736,7 +1742,7 @@ static noinline ssize_t btrfs_buffered_write(struct kiocb *iocb, 
		WARN_ON(reserve_bytes == 0);

		ret = btrfs_delalloc_reserve_metadata(BTRFS_I(inode),

						      reserve_bytes,

						      reserve_bytes, false);

						      reserve_bytes, nowait);

		if (ret) {

			if (!only_release_metadata)

				btrfs_free_reserved_data_space(BTRFS_I(inode),
@@ -1765,10 +1771,11 @@ static noinline ssize_t btrfs_buffered_write(struct kiocb *iocb, 
		extents_locked = lock_and_cleanup_extent_if_need(

				BTRFS_I(inode), pages,

				num_pages, pos, write_bytes, &lockstart,

				&lockend, false, &cached_state);

				&lockend, nowait, &cached_state);

		if (extents_locked < 0) {

			if (extents_locked == -EAGAIN)

			if (!nowait && extents_locked == -EAGAIN)

				goto again;



			btrfs_delalloc_release_extents(BTRFS_I(inode),

						       reserve_bytes);

			ret = extents_locked;