Commit 690c2a38 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Darrick J. Wong
Browse files

xfs: split out a new set of read-only iomap ops 



Start untangling xfs_file_iomap_begin by splitting out the read-only
case into its own set of iomap_ops with a very simply iomap_begin
helper.

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 43568226

fs/xfs/xfs_aops.c

+5 −4
Original line number Diff line number Diff line
@@ -634,7 +634,7 @@ xfs_vm_bmap( 
	 */

	if (xfs_is_cow_inode(ip) || XFS_IS_REALTIME_INODE(ip))

		return 0;

	return iomap_bmap(mapping, block, &xfs_iomap_ops);

	return iomap_bmap(mapping, block, &xfs_read_iomap_ops);

}



STATIC int
@@ -642,7 +642,7 @@ xfs_vm_readpage( 
	struct file		*unused,

	struct page		*page)

{

	return iomap_readpage(page, &xfs_iomap_ops);

	return iomap_readpage(page, &xfs_read_iomap_ops);

}



STATIC int
@@ -652,7 +652,7 @@ xfs_vm_readpages( 
	struct list_head	*pages,

	unsigned		nr_pages)

{

	return iomap_readpages(mapping, pages, nr_pages, &xfs_iomap_ops);

	return iomap_readpages(mapping, pages, nr_pages, &xfs_read_iomap_ops);

}



static int
@@ -662,7 +662,8 @@ xfs_iomap_swapfile_activate( 
	sector_t			*span)

{

	sis->bdev = xfs_find_bdev_for_inode(file_inode(swap_file));

	return iomap_swapfile_activate(sis, swap_file, span, &xfs_iomap_ops);

	return iomap_swapfile_activate(sis, swap_file, span,

			&xfs_read_iomap_ops);

}



const struct address_space_operations xfs_address_space_operations = {

fs/xfs/xfs_file.c

+6 −3
Original line number Diff line number Diff line
@@ -188,7 +188,8 @@ xfs_file_dio_aio_read( 
	file_accessed(iocb->ki_filp);



	xfs_ilock(ip, XFS_IOLOCK_SHARED);

	ret = iomap_dio_rw(iocb, to, &xfs_iomap_ops, NULL, is_sync_kiocb(iocb));

	ret = iomap_dio_rw(iocb, to, &xfs_read_iomap_ops, NULL,

			is_sync_kiocb(iocb));

	xfs_iunlock(ip, XFS_IOLOCK_SHARED);



	return ret;
@@ -215,7 +216,7 @@ xfs_file_dax_read( 
		xfs_ilock(ip, XFS_IOLOCK_SHARED);

	}



	ret = dax_iomap_rw(iocb, to, &xfs_iomap_ops);

	ret = dax_iomap_rw(iocb, to, &xfs_read_iomap_ops);

	xfs_iunlock(ip, XFS_IOLOCK_SHARED);



	file_accessed(iocb->ki_filp);
@@ -1153,7 +1154,9 @@ __xfs_filemap_fault( 
	if (IS_DAX(inode)) {

		pfn_t pfn;



		ret = dax_iomap_fault(vmf, pe_size, &pfn, NULL, &xfs_iomap_ops);

		ret = dax_iomap_fault(vmf, pe_size, &pfn, NULL,

				(write_fault && !vmf->cow_page) ?

				 &xfs_iomap_ops : &xfs_read_iomap_ops);

		if (ret & VM_FAULT_NEEDDSYNC)

			ret = dax_finish_sync_fault(vmf, pe_size, pfn);

	} else {

fs/xfs/xfs_iomap.c

+47 −16
Original line number Diff line number Diff line
@@ -950,11 +950,13 @@ xfs_file_iomap_begin( 
	u16			iomap_flags = 0;

	unsigned		lockmode;



	ASSERT(flags & (IOMAP_WRITE | IOMAP_ZERO));



	if (XFS_FORCED_SHUTDOWN(mp))

		return -EIO;



	if ((flags & (IOMAP_WRITE | IOMAP_ZERO)) && !(flags & IOMAP_DIRECT) &&

			!IS_DAX(inode) && !xfs_get_extsz_hint(ip)) {

	if (!(flags & IOMAP_DIRECT) && !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, srcmap);
@@ -975,17 +977,6 @@ xfs_file_iomap_begin( 
	if (error)

		goto out_unlock;



	if (flags & IOMAP_REPORT) {

		/* Trim the mapping to the nearest shared extent boundary. */

		error = xfs_reflink_trim_around_shared(ip, &imap, &shared);

		if (error)

			goto out_unlock;

	}



	/* Non-modifying mapping requested, so we are done */

	if (!(flags & (IOMAP_WRITE | IOMAP_ZERO)))

		goto out_found;



	/*

	 * Break shared extents if necessary. Checks for non-blocking IO have

	 * been done up front, so we don't need to do them here.
@@ -1051,10 +1042,8 @@ xfs_file_iomap_begin( 
	 * so consider them to be dirty for the purposes of O_DSYNC even if

	 * there is no other metadata changes pending or have been made here.

	 */

	if ((flags & IOMAP_WRITE) && offset + length > i_size_read(inode))

	if (offset + length > i_size_read(inode))

		iomap_flags |= IOMAP_F_DIRTY;

	if (shared)

		iomap_flags |= IOMAP_F_SHARED;

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



out_found:
@@ -1157,6 +1146,48 @@ const struct iomap_ops xfs_iomap_ops = { 
	.iomap_end		= xfs_file_iomap_end,

};



static int

xfs_read_iomap_begin(

	struct inode		*inode,

	loff_t			offset,

	loff_t			length,

	unsigned		flags,

	struct iomap		*iomap,

	struct iomap		*srcmap)

{

	struct xfs_inode	*ip = XFS_I(inode);

	struct xfs_mount	*mp = ip->i_mount;

	struct xfs_bmbt_irec	imap;

	xfs_fileoff_t		offset_fsb = XFS_B_TO_FSBT(mp, offset);

	xfs_fileoff_t		end_fsb = xfs_iomap_end_fsb(mp, offset, length);

	int			nimaps = 1, error = 0;

	bool			shared = false;

	unsigned		lockmode;



	ASSERT(!(flags & (IOMAP_WRITE | IOMAP_ZERO)));



	if (XFS_FORCED_SHUTDOWN(mp))

		return -EIO;



	error = xfs_ilock_for_iomap(ip, flags, &lockmode);

	if (error)

		return error;

	error = xfs_bmapi_read(ip, offset_fsb, end_fsb - offset_fsb, &imap,

			       &nimaps, 0);

	if (!error && (flags & IOMAP_REPORT))

		error = xfs_reflink_trim_around_shared(ip, &imap, &shared);

	xfs_iunlock(ip, lockmode);



	if (error)

		return error;

	trace_xfs_iomap_found(ip, offset, length, XFS_DATA_FORK, &imap);

	return xfs_bmbt_to_iomap(ip, iomap, &imap, shared ? IOMAP_F_SHARED : 0);

}



const struct iomap_ops xfs_read_iomap_ops = {

	.iomap_begin		= xfs_read_iomap_begin,

};



static int

xfs_seek_iomap_begin(

	struct inode		*inode,

fs/xfs/xfs_iomap.h

+1 −0
Original line number Diff line number Diff line
@@ -40,6 +40,7 @@ xfs_aligned_fsb_count( 
}



extern const struct iomap_ops xfs_iomap_ops;

extern const struct iomap_ops xfs_read_iomap_ops;

extern const struct iomap_ops xfs_seek_iomap_ops;

extern const struct iomap_ops xfs_xattr_iomap_ops;

fs/xfs/xfs_iops.c

+1 −1
Original line number Diff line number Diff line
@@ -1114,7 +1114,7 @@ xfs_vn_fiemap( 
				&xfs_xattr_iomap_ops);

	} else {

		error = iomap_fiemap(inode, fieinfo, start, length,

				&xfs_iomap_ops);

				&xfs_read_iomap_ops);

	}

	xfs_iunlock(XFS_I(inode), XFS_IOLOCK_SHARED);