Commit 3f165b33 authored by Darrick J. Wong's avatar Darrick J. Wong
Browse files

xfs: convert unwritten status of reverse mappings for shared files 



Provide a function to convert an unwritten extent to a real one and
vice versa when shared extents are possible.

Signed-off-by: default avatarDarrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
parent ceeb9c83

fs/xfs/libxfs/xfs_rmap.c

+384 −1
Original line number Diff line number Diff line
@@ -1278,6 +1278,384 @@ xfs_rmap_convert( 
	return error;

}



/*

 * Convert an unwritten extent to a real extent or vice versa.  If there is no

 * possibility of overlapping extents, delegate to the simpler convert

 * function.

 */

STATIC int

xfs_rmap_convert_shared(

	struct xfs_btree_cur	*cur,

	xfs_agblock_t		bno,

	xfs_extlen_t		len,

	bool			unwritten,

	struct xfs_owner_info	*oinfo)

{

	struct xfs_mount	*mp = cur->bc_mp;

	struct xfs_rmap_irec	r[4];	/* neighbor extent entries */

					/* left is 0, right is 1, prev is 2 */

					/* new is 3 */

	uint64_t		owner;

	uint64_t		offset;

	uint64_t		new_endoff;

	unsigned int		oldext;

	unsigned int		newext;

	unsigned int		flags = 0;

	int			i;

	int			state = 0;

	int			error;



	xfs_owner_info_unpack(oinfo, &owner, &offset, &flags);

	ASSERT(!(XFS_RMAP_NON_INODE_OWNER(owner) ||

			(flags & (XFS_RMAP_ATTR_FORK | XFS_RMAP_BMBT_BLOCK))));

	oldext = unwritten ? XFS_RMAP_UNWRITTEN : 0;

	new_endoff = offset + len;

	trace_xfs_rmap_convert(mp, cur->bc_private.a.agno, bno, len,

			unwritten, oinfo);



	/*

	 * For the initial lookup, look for and exact match or the left-adjacent

	 * record for our insertion point. This will also give us the record for

	 * start block contiguity tests.

	 */

	error = xfs_rmap_lookup_le_range(cur, bno, owner, offset, flags,

			&PREV, &i);

	XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);



	ASSERT(PREV.rm_offset <= offset);

	ASSERT(PREV.rm_offset + PREV.rm_blockcount >= new_endoff);

	ASSERT((PREV.rm_flags & XFS_RMAP_UNWRITTEN) == oldext);

	newext = ~oldext & XFS_RMAP_UNWRITTEN;



	/*

	 * Set flags determining what part of the previous oldext allocation

	 * extent is being replaced by a newext allocation.

	 */

	if (PREV.rm_offset == offset)

		state |= RMAP_LEFT_FILLING;

	if (PREV.rm_offset + PREV.rm_blockcount == new_endoff)

		state |= RMAP_RIGHT_FILLING;



	/* Is there a left record that abuts our range? */

	error = xfs_rmap_find_left_neighbor(cur, bno, owner, offset, newext,

			&LEFT, &i);

	if (error)

		goto done;

	if (i) {

		state |= RMAP_LEFT_VALID;

		XFS_WANT_CORRUPTED_GOTO(mp,

				LEFT.rm_startblock + LEFT.rm_blockcount <= bno,

				done);

		if (xfs_rmap_is_mergeable(&LEFT, owner, newext))

			state |= RMAP_LEFT_CONTIG;

	}



	/* Is there a right record that abuts our range? */

	error = xfs_rmap_lookup_eq(cur, bno + len, len, owner, offset + len,

			newext, &i);

	if (error)

		goto done;

	if (i) {

		state |= RMAP_RIGHT_VALID;

		error = xfs_rmap_get_rec(cur, &RIGHT, &i);

		if (error)

			goto done;

		XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);

		XFS_WANT_CORRUPTED_GOTO(mp, bno + len <= RIGHT.rm_startblock,

				done);

		trace_xfs_rmap_find_right_neighbor_result(cur->bc_mp,

				cur->bc_private.a.agno, RIGHT.rm_startblock,

				RIGHT.rm_blockcount, RIGHT.rm_owner,

				RIGHT.rm_offset, RIGHT.rm_flags);

		if (xfs_rmap_is_mergeable(&RIGHT, owner, newext))

			state |= RMAP_RIGHT_CONTIG;

	}



	/* check that left + prev + right is not too long */

	if ((state & (RMAP_LEFT_FILLING | RMAP_LEFT_CONTIG |

			 RMAP_RIGHT_FILLING | RMAP_RIGHT_CONTIG)) ==

	    (RMAP_LEFT_FILLING | RMAP_LEFT_CONTIG |

	     RMAP_RIGHT_FILLING | RMAP_RIGHT_CONTIG) &&

	    (unsigned long)LEFT.rm_blockcount + len +

	     RIGHT.rm_blockcount > XFS_RMAP_LEN_MAX)

		state &= ~RMAP_RIGHT_CONTIG;



	trace_xfs_rmap_convert_state(mp, cur->bc_private.a.agno, state,

			_RET_IP_);

	/*

	 * Switch out based on the FILLING and CONTIG state bits.

	 */

	switch (state & (RMAP_LEFT_FILLING | RMAP_LEFT_CONTIG |

			 RMAP_RIGHT_FILLING | RMAP_RIGHT_CONTIG)) {

	case RMAP_LEFT_FILLING | RMAP_LEFT_CONTIG |

	     RMAP_RIGHT_FILLING | RMAP_RIGHT_CONTIG:

		/*

		 * Setting all of a previous oldext extent to newext.

		 * The left and right neighbors are both contiguous with new.

		 */

		error = xfs_rmap_delete(cur, RIGHT.rm_startblock,

				RIGHT.rm_blockcount, RIGHT.rm_owner,

				RIGHT.rm_offset, RIGHT.rm_flags);

		if (error)

			goto done;

		error = xfs_rmap_delete(cur, PREV.rm_startblock,

				PREV.rm_blockcount, PREV.rm_owner,

				PREV.rm_offset, PREV.rm_flags);

		if (error)

			goto done;

		NEW = LEFT;

		error = xfs_rmap_lookup_eq(cur, NEW.rm_startblock,

				NEW.rm_blockcount, NEW.rm_owner,

				NEW.rm_offset, NEW.rm_flags, &i);

		if (error)

			goto done;

		XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);

		NEW.rm_blockcount += PREV.rm_blockcount + RIGHT.rm_blockcount;

		error = xfs_rmap_update(cur, &NEW);

		if (error)

			goto done;

		break;



	case RMAP_LEFT_FILLING | RMAP_RIGHT_FILLING | RMAP_LEFT_CONTIG:

		/*

		 * Setting all of a previous oldext extent to newext.

		 * The left neighbor is contiguous, the right is not.

		 */

		error = xfs_rmap_delete(cur, PREV.rm_startblock,

				PREV.rm_blockcount, PREV.rm_owner,

				PREV.rm_offset, PREV.rm_flags);

		if (error)

			goto done;

		NEW = LEFT;

		error = xfs_rmap_lookup_eq(cur, NEW.rm_startblock,

				NEW.rm_blockcount, NEW.rm_owner,

				NEW.rm_offset, NEW.rm_flags, &i);

		if (error)

			goto done;

		XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);

		NEW.rm_blockcount += PREV.rm_blockcount;

		error = xfs_rmap_update(cur, &NEW);

		if (error)

			goto done;

		break;



	case RMAP_LEFT_FILLING | RMAP_RIGHT_FILLING | RMAP_RIGHT_CONTIG:

		/*

		 * Setting all of a previous oldext extent to newext.

		 * The right neighbor is contiguous, the left is not.

		 */

		error = xfs_rmap_delete(cur, RIGHT.rm_startblock,

				RIGHT.rm_blockcount, RIGHT.rm_owner,

				RIGHT.rm_offset, RIGHT.rm_flags);

		if (error)

			goto done;

		NEW = PREV;

		error = xfs_rmap_lookup_eq(cur, NEW.rm_startblock,

				NEW.rm_blockcount, NEW.rm_owner,

				NEW.rm_offset, NEW.rm_flags, &i);

		if (error)

			goto done;

		XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);

		NEW.rm_blockcount += RIGHT.rm_blockcount;

		NEW.rm_flags = RIGHT.rm_flags;

		error = xfs_rmap_update(cur, &NEW);

		if (error)

			goto done;

		break;



	case RMAP_LEFT_FILLING | RMAP_RIGHT_FILLING:

		/*

		 * Setting all of a previous oldext extent to newext.

		 * Neither the left nor right neighbors are contiguous with

		 * the new one.

		 */

		NEW = PREV;

		error = xfs_rmap_lookup_eq(cur, NEW.rm_startblock,

				NEW.rm_blockcount, NEW.rm_owner,

				NEW.rm_offset, NEW.rm_flags, &i);

		if (error)

			goto done;

		XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);

		NEW.rm_flags = newext;

		error = xfs_rmap_update(cur, &NEW);

		if (error)

			goto done;

		break;



	case RMAP_LEFT_FILLING | RMAP_LEFT_CONTIG:

		/*

		 * Setting the first part of a previous oldext extent to newext.

		 * The left neighbor is contiguous.

		 */

		NEW = PREV;

		error = xfs_rmap_delete(cur, NEW.rm_startblock,

				NEW.rm_blockcount, NEW.rm_owner,

				NEW.rm_offset, NEW.rm_flags);

		if (error)

			goto done;

		NEW.rm_offset += len;

		NEW.rm_startblock += len;

		NEW.rm_blockcount -= len;

		error = xfs_rmap_insert(cur, NEW.rm_startblock,

				NEW.rm_blockcount, NEW.rm_owner,

				NEW.rm_offset, NEW.rm_flags);

		if (error)

			goto done;

		NEW = LEFT;

		error = xfs_rmap_lookup_eq(cur, NEW.rm_startblock,

				NEW.rm_blockcount, NEW.rm_owner,

				NEW.rm_offset, NEW.rm_flags, &i);

		if (error)

			goto done;

		XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);

		NEW.rm_blockcount += len;

		error = xfs_rmap_update(cur, &NEW);

		if (error)

			goto done;

		break;



	case RMAP_LEFT_FILLING:

		/*

		 * Setting the first part of a previous oldext extent to newext.

		 * The left neighbor is not contiguous.

		 */

		NEW = PREV;

		error = xfs_rmap_delete(cur, NEW.rm_startblock,

				NEW.rm_blockcount, NEW.rm_owner,

				NEW.rm_offset, NEW.rm_flags);

		if (error)

			goto done;

		NEW.rm_offset += len;

		NEW.rm_startblock += len;

		NEW.rm_blockcount -= len;

		error = xfs_rmap_insert(cur, NEW.rm_startblock,

				NEW.rm_blockcount, NEW.rm_owner,

				NEW.rm_offset, NEW.rm_flags);

		if (error)

			goto done;

		error = xfs_rmap_insert(cur, bno, len, owner, offset, newext);

		if (error)

			goto done;

		break;



	case RMAP_RIGHT_FILLING | RMAP_RIGHT_CONTIG:

		/*

		 * Setting the last part of a previous oldext extent to newext.

		 * The right neighbor is contiguous with the new allocation.

		 */

		NEW = PREV;

		error = xfs_rmap_lookup_eq(cur, NEW.rm_startblock,

				NEW.rm_blockcount, NEW.rm_owner,

				NEW.rm_offset, NEW.rm_flags, &i);

		if (error)

			goto done;

		XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);

		NEW.rm_blockcount = offset - NEW.rm_offset;

		error = xfs_rmap_update(cur, &NEW);

		if (error)

			goto done;

		NEW = RIGHT;

		error = xfs_rmap_delete(cur, NEW.rm_startblock,

				NEW.rm_blockcount, NEW.rm_owner,

				NEW.rm_offset, NEW.rm_flags);

		if (error)

			goto done;

		NEW.rm_offset = offset;

		NEW.rm_startblock = bno;

		NEW.rm_blockcount += len;

		error = xfs_rmap_insert(cur, NEW.rm_startblock,

				NEW.rm_blockcount, NEW.rm_owner,

				NEW.rm_offset, NEW.rm_flags);

		if (error)

			goto done;

		break;



	case RMAP_RIGHT_FILLING:

		/*

		 * Setting the last part of a previous oldext extent to newext.

		 * The right neighbor is not contiguous.

		 */

		NEW = PREV;

		error = xfs_rmap_lookup_eq(cur, NEW.rm_startblock,

				NEW.rm_blockcount, NEW.rm_owner,

				NEW.rm_offset, NEW.rm_flags, &i);

		if (error)

			goto done;

		XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);

		NEW.rm_blockcount -= len;

		error = xfs_rmap_update(cur, &NEW);

		if (error)

			goto done;

		error = xfs_rmap_insert(cur, bno, len, owner, offset, newext);

		if (error)

			goto done;

		break;



	case 0:

		/*

		 * Setting the middle part of a previous oldext extent to

		 * newext.  Contiguity is impossible here.

		 * One extent becomes three extents.

		 */

		/* new right extent - oldext */

		NEW.rm_startblock = bno + len;

		NEW.rm_owner = owner;

		NEW.rm_offset = new_endoff;

		NEW.rm_blockcount = PREV.rm_offset + PREV.rm_blockcount -

				new_endoff;

		NEW.rm_flags = PREV.rm_flags;

		error = xfs_rmap_insert(cur, NEW.rm_startblock,

				NEW.rm_blockcount, NEW.rm_owner, NEW.rm_offset,

				NEW.rm_flags);

		if (error)

			goto done;

		/* new left extent - oldext */

		NEW = PREV;

		error = xfs_rmap_lookup_eq(cur, NEW.rm_startblock,

				NEW.rm_blockcount, NEW.rm_owner,

				NEW.rm_offset, NEW.rm_flags, &i);

		if (error)

			goto done;

		XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);

		NEW.rm_blockcount = offset - NEW.rm_offset;

		error = xfs_rmap_update(cur, &NEW);

		if (error)

			goto done;

		/* new middle extent - newext */

		NEW.rm_startblock = bno;

		NEW.rm_blockcount = len;

		NEW.rm_owner = owner;

		NEW.rm_offset = offset;

		NEW.rm_flags = newext;

		error = xfs_rmap_insert(cur, NEW.rm_startblock,

				NEW.rm_blockcount, NEW.rm_owner, NEW.rm_offset,

				NEW.rm_flags);

		if (error)

			goto done;

		break;



	case RMAP_LEFT_FILLING | RMAP_LEFT_CONTIG | RMAP_RIGHT_CONTIG:

	case RMAP_RIGHT_FILLING | RMAP_LEFT_CONTIG | RMAP_RIGHT_CONTIG:

	case RMAP_LEFT_FILLING | RMAP_RIGHT_CONTIG:

	case RMAP_RIGHT_FILLING | RMAP_LEFT_CONTIG:

	case RMAP_LEFT_CONTIG | RMAP_RIGHT_CONTIG:

	case RMAP_LEFT_CONTIG:

	case RMAP_RIGHT_CONTIG:

		/*

		 * These cases are all impossible.

		 */

		ASSERT(0);

	}



	trace_xfs_rmap_convert_done(mp, cur->bc_private.a.agno, bno, len,

			unwritten, oinfo);

done:

	if (error)

		trace_xfs_rmap_convert_error(cur->bc_mp,

				cur->bc_private.a.agno, error, _RET_IP_);

	return error;

}



#undef	NEW

#undef	LEFT

#undef	RIGHT
@@ -1754,6 +2132,10 @@ xfs_rmap_finish_one( 
		error = xfs_rmap_convert(rcur, bno, blockcount, !unwritten,

				&oinfo);

		break;

	case XFS_RMAP_CONVERT_SHARED:

		error = xfs_rmap_convert_shared(rcur, bno, blockcount,

				!unwritten, &oinfo);

		break;

	default:

		ASSERT(0);

		error = -EFSCORRUPTED;
@@ -1857,7 +2239,8 @@ xfs_rmap_convert_extent( 
	if (!xfs_rmap_update_is_needed(mp, whichfork))

		return 0;



	return __xfs_rmap_add(mp, dfops, XFS_RMAP_CONVERT, ip->i_ino,

	return __xfs_rmap_add(mp, dfops, xfs_is_reflink_inode(ip) ?

			XFS_RMAP_CONVERT_SHARED : XFS_RMAP_CONVERT, ip->i_ino,

			whichfork, PREV);

}

fs/xfs/xfs_rmap_item.c

+3 −0
Original line number Diff line number Diff line
@@ -496,6 +496,9 @@ xfs_rui_recover( 
		case XFS_RMAP_EXTENT_CONVERT:

			type = XFS_RMAP_CONVERT;

			break;

		case XFS_RMAP_EXTENT_CONVERT_SHARED:

			type = XFS_RMAP_CONVERT_SHARED;

			break;

		case XFS_RMAP_EXTENT_ALLOC:

			type = XFS_RMAP_ALLOC;

			break;