Commit 8b813568 authored by Dave Chinner's avatar Dave Chinner
Browse files

xfs: move the minimum agno checks into xfs_alloc_vextent_check_args 



All of the allocation functions now extract the minimum allowed AG
from the transaction and then use it in some way. The allocation
functions that are restricted to a single AG all check if the
AG requested can be allocated from and return an error if so. These
all set args->agno appropriately.

All the allocation functions that iterate AGs use it to calculate
the scan start AG. args->agno is not set until the iterator starts
walking AGs.

Hence we can easily set up a conditional check against the minimum
AG allowed in xfs_alloc_vextent_check_args() based on whether
args->agno contains NULLAGNUMBER or not and move all the repeated
setup code to xfs_alloc_vextent_check_args(), further simplifying
the allocation functions.

Signed-off-by: default avatarDave Chinner <dchinner@redhat.com>
Reviewed-by: default avatarDarrick J. Wong <djwong@kernel.org>
parent 230e8fe8

fs/xfs/libxfs/xfs_alloc.c

+33 −55
Original line number Diff line number Diff line
@@ -3089,14 +3089,18 @@ xfs_alloc_read_agf( 
static int

xfs_alloc_vextent_check_args(

	struct xfs_alloc_arg	*args,

	xfs_fsblock_t		target)

	xfs_fsblock_t		target,

	xfs_agnumber_t		*minimum_agno)

{

	struct xfs_mount	*mp = args->mp;

	xfs_agblock_t		agsize;



	args->agbno = NULLAGBLOCK;

	args->fsbno = NULLFSBLOCK;



	*minimum_agno = 0;

	if (args->tp->t_highest_agno != NULLAGNUMBER)

		*minimum_agno = args->tp->t_highest_agno;



	/*

	 * Just fix this up, for the case where the last a.g. is shorter

	 * (or there's only one a.g.) and the caller couldn't easily figure
@@ -3123,11 +3127,16 @@ xfs_alloc_vextent_check_args( 
	    XFS_FSB_TO_AGBNO(mp, target) >= agsize ||

	    args->minlen > args->maxlen || args->minlen > agsize ||

	    args->mod >= args->prod) {

		args->fsbno = NULLFSBLOCK;

		trace_xfs_alloc_vextent_badargs(args);

		return -ENOSPC;

	}



	if (args->agno != NULLAGNUMBER && *minimum_agno > args->agno) {

		trace_xfs_alloc_vextent_skip_deadlock(args);

		return -ENOSPC;

	}

	return 0;



}



/*
@@ -3266,28 +3275,19 @@ xfs_alloc_vextent_this_ag( 
	xfs_agnumber_t		agno)

{

	struct xfs_mount	*mp = args->mp;

	xfs_agnumber_t		minimum_agno = 0;

	xfs_agnumber_t		minimum_agno;

	int			error;



	if (args->tp->t_highest_agno != NULLAGNUMBER)

		minimum_agno = args->tp->t_highest_agno;



	if (minimum_agno > agno) {

		trace_xfs_alloc_vextent_skip_deadlock(args);

		args->fsbno = NULLFSBLOCK;

		return 0;

	}



	error = xfs_alloc_vextent_check_args(args, XFS_AGB_TO_FSB(mp, agno, 0));

	args->agno = agno;

	args->agbno = 0;

	error = xfs_alloc_vextent_check_args(args, XFS_AGB_TO_FSB(mp, agno, 0),

			&minimum_agno);

	if (error) {

		if (error == -ENOSPC)

			return 0;

		return error;

	}



	args->agno = agno;

	args->agbno = 0;



	error = xfs_alloc_vextent_prepare_ag(args);

	if (!error && args->agbp)

		error = xfs_alloc_ag_vextent_size(args);
@@ -3400,16 +3400,15 @@ xfs_alloc_vextent_start_ag( 
	xfs_fsblock_t		target)

{

	struct xfs_mount	*mp = args->mp;

	xfs_agnumber_t		minimum_agno = 0;

	xfs_agnumber_t		minimum_agno;

	xfs_agnumber_t		start_agno;

	xfs_agnumber_t		rotorstep = xfs_rotorstep;

	bool			bump_rotor = false;

	int			error;



	if (args->tp->t_highest_agno != NULLAGNUMBER)

		minimum_agno = args->tp->t_highest_agno;



	error = xfs_alloc_vextent_check_args(args, target);

	args->agno = NULLAGNUMBER;

	args->agbno = NULLAGBLOCK;

	error = xfs_alloc_vextent_check_args(args, target, &minimum_agno);

	if (error) {

		if (error == -ENOSPC)

			return 0;
@@ -3451,14 +3450,13 @@ xfs_alloc_vextent_first_ag( 
	xfs_fsblock_t		target)

 {

	struct xfs_mount	*mp = args->mp;

	xfs_agnumber_t		minimum_agno = 0;

	xfs_agnumber_t		minimum_agno;

	xfs_agnumber_t		start_agno;

	int			error;



	if (args->tp->t_highest_agno != NULLAGNUMBER)

		minimum_agno = args->tp->t_highest_agno;



	error = xfs_alloc_vextent_check_args(args, target);

	args->agno = NULLAGNUMBER;

	args->agbno = NULLAGBLOCK;

	error = xfs_alloc_vextent_check_args(args, target, &minimum_agno);

	if (error) {

		if (error == -ENOSPC)

			return 0;
@@ -3481,28 +3479,18 @@ xfs_alloc_vextent_exact_bno( 
	xfs_fsblock_t		target)

{

	struct xfs_mount	*mp = args->mp;

	xfs_agnumber_t		minimum_agno = 0;

	xfs_agnumber_t		minimum_agno;

	int			error;



	if (args->tp->t_highest_agno != NULLAGNUMBER)

		minimum_agno = args->tp->t_highest_agno;



	error = xfs_alloc_vextent_check_args(args, target);

	args->agno = XFS_FSB_TO_AGNO(mp, target);

	args->agbno = XFS_FSB_TO_AGBNO(mp, target);

	error = xfs_alloc_vextent_check_args(args, target, &minimum_agno);

	if (error) {

		if (error == -ENOSPC)

			return 0;

		return error;

	}



	args->agno = XFS_FSB_TO_AGNO(mp, target);

	if (minimum_agno > args->agno) {

		trace_xfs_alloc_vextent_skip_deadlock(args);

		args->fsbno = NULLFSBLOCK;

		return 0;

	}



	args->agbno = XFS_FSB_TO_AGBNO(mp, target);



	error = xfs_alloc_vextent_prepare_ag(args);

	if (!error && args->agbp)

		error = xfs_alloc_ag_vextent_exact(args);
@@ -3522,32 +3510,22 @@ xfs_alloc_vextent_near_bno( 
	xfs_fsblock_t		target)

{

	struct xfs_mount	*mp = args->mp;

	xfs_agnumber_t		minimum_agno = 0;

	xfs_agnumber_t		minimum_agno;

	bool			needs_perag = args->pag == NULL;

	int			error;



	if (args->tp->t_highest_agno != NULLAGNUMBER)

		minimum_agno = args->tp->t_highest_agno;



	error = xfs_alloc_vextent_check_args(args, target);

	args->agno = XFS_FSB_TO_AGNO(mp, target);

	args->agbno = XFS_FSB_TO_AGBNO(mp, target);

	error = xfs_alloc_vextent_check_args(args, target, &minimum_agno);

	if (error) {

		if (error == -ENOSPC)

			return 0;

		return error;

	}



	args->agno = XFS_FSB_TO_AGNO(mp, target);

	if (minimum_agno > args->agno) {

		trace_xfs_alloc_vextent_skip_deadlock(args);

		args->fsbno = NULLFSBLOCK;

		return 0;

	}



	if (needs_perag)

		args->pag = xfs_perag_get(mp, args->agno);



	args->agbno = XFS_FSB_TO_AGBNO(mp, target);



	error = xfs_alloc_vextent_prepare_ag(args);

	if (!error && args->agbp)

		error = xfs_alloc_ag_vextent_near(args);