Commit 36adcbac authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Darrick J. Wong
Browse files

xfs: fill out the srcmap in iomap_begin 



Replace our local hacks to report the source block in the main iomap
with the proper scrmap reporting.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: default avatarDarrick J. Wong <darrick.wong@oracle.com>
parent ae36b53c

fs/xfs/xfs_iomap.c

+24 −25
Original line number Diff line number Diff line
@@ -527,7 +527,8 @@ xfs_file_iomap_begin_delay( 
	loff_t			offset,

	loff_t			count,

	unsigned		flags,

	struct iomap		*iomap)

	struct iomap		*iomap,

	struct iomap		*srcmap)

{

	struct xfs_inode	*ip = XFS_I(inode);

	struct xfs_mount	*mp = ip->i_mount;
@@ -721,11 +722,13 @@ xfs_file_iomap_begin_delay( 
found_cow:

	xfs_iunlock(ip, XFS_ILOCK_EXCL);

	if (imap.br_startoff <= offset_fsb) {

		/* ensure we only report blocks we have a reservation for */

		xfs_trim_extent(&imap, cmap.br_startoff, cmap.br_blockcount);

		return xfs_bmbt_to_iomap(ip, iomap, &imap, IOMAP_F_SHARED);

		error = xfs_bmbt_to_iomap(ip, srcmap, &imap, 0);

		if (error)

			return error;

	} else {

		xfs_trim_extent(&cmap, offset_fsb,

				imap.br_startoff - offset_fsb);

	}

	xfs_trim_extent(&cmap, offset_fsb, imap.br_startoff - offset_fsb);

	return xfs_bmbt_to_iomap(ip, iomap, &cmap, IOMAP_F_SHARED);



out_unlock:
@@ -933,7 +936,7 @@ xfs_file_iomap_begin( 
{

	struct xfs_inode	*ip = XFS_I(inode);

	struct xfs_mount	*mp = ip->i_mount;

	struct xfs_bmbt_irec	imap;

	struct xfs_bmbt_irec	imap, cmap;

	xfs_fileoff_t		offset_fsb, end_fsb;

	int			nimaps = 1, error = 0;

	bool			shared = false;
@@ -947,7 +950,7 @@ xfs_file_iomap_begin( 
			!IS_DAX(inode) && !xfs_get_extsz_hint(ip)) {

		/* Reserve delalloc blocks for regular writeback. */

		return xfs_file_iomap_begin_delay(inode, offset, length, flags,

				iomap);

				iomap, srcmap);

	}



	/*
@@ -987,9 +990,6 @@ xfs_file_iomap_begin( 
	 * been done up front, so we don't need to do them here.

	 */

	if (xfs_is_cow_inode(ip)) {

		struct xfs_bmbt_irec	cmap;

		bool			directio = (flags & IOMAP_DIRECT);



		/* if zeroing doesn't need COW allocation, then we are done. */

		if ((flags & IOMAP_ZERO) &&

		    !needs_cow_for_zeroing(&imap, nimaps))
@@ -997,23 +997,11 @@ xfs_file_iomap_begin( 


		/* may drop and re-acquire the ilock */

		error = xfs_reflink_allocate_cow(ip, &imap, &cmap, &shared,

				&lockmode, directio);

				&lockmode, flags & IOMAP_DIRECT);

		if (error)

			goto out_unlock;



		/*

		 * For buffered writes we need to report the address of the

		 * previous block (if there was any) so that the higher level

		 * write code can perform read-modify-write operations; we

		 * won't need the CoW fork mapping until writeback.  For direct

		 * I/O, which must be block aligned, we need to report the

		 * newly allocated address.  If the data fork has a hole, copy

		 * the COW fork mapping to avoid allocating to the data fork.

		 */

		if (shared &&

		    (directio || imap.br_startblock == HOLESTARTBLOCK))

			imap = cmap;



		if (shared)

			goto out_found_cow;

		end_fsb = imap.br_startoff + imap.br_blockcount;

		length = XFS_FSB_TO_B(mp, end_fsb) - offset;

	}
@@ -1074,6 +1062,17 @@ xfs_file_iomap_begin( 
	trace_xfs_iomap_found(ip, offset, length, XFS_DATA_FORK, &imap);

	goto out_finish;



out_found_cow:

	xfs_iunlock(ip, lockmode);

	length = XFS_FSB_TO_B(mp, cmap.br_startoff + cmap.br_blockcount);

	trace_xfs_iomap_found(ip, offset, length - offset, XFS_COW_FORK, &cmap);

	if (imap.br_startblock != HOLESTARTBLOCK) {

		error = xfs_bmbt_to_iomap(ip, srcmap, &imap, 0);

		if (error)

			return error;

	}

	return xfs_bmbt_to_iomap(ip, iomap, &cmap, IOMAP_F_SHARED);



out_unlock:

	xfs_iunlock(ip, lockmode);

	return error;