Commit c467c049 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Alex Elder
Browse files

xfs: split xfs_bmap_btalloc 



Split out the nullfb case into a separate function to reduce the stack
footprint and make the code more readable.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarDave Chinner <david@fromorbit.com>
Signed-off-by: default avatarAlex Elder <aelder@sgi.com>
parent f7008d0a

fs/xfs/xfs_bmap.c

+119 −101
Original line number Diff line number Diff line
@@ -2550,106 +2550,56 @@ xfs_bmap_rtalloc( 
}



STATIC int

xfs_bmap_btalloc(

	xfs_bmalloca_t	*ap)		/* bmap alloc argument struct */

xfs_bmap_btalloc_nullfb(

	struct xfs_bmalloca	*ap,

	struct xfs_alloc_arg	*args,

	xfs_extlen_t		*blen)

{

	xfs_mount_t	*mp;		/* mount point structure */

	xfs_alloctype_t	atype = 0;	/* type for allocation routines */

	xfs_extlen_t	align;		/* minimum allocation alignment */

	xfs_agnumber_t	ag;

	xfs_agnumber_t	fb_agno;	/* ag number of ap->firstblock */

	xfs_agnumber_t	startag;

	xfs_alloc_arg_t	args;

	xfs_extlen_t	blen;

	xfs_extlen_t	nextminlen = 0;

	xfs_perag_t	*pag;

	int		nullfb;		/* true if ap->firstblock isn't set */

	int		isaligned;

	int		notinit;

	int		tryagain;

	struct xfs_mount	*mp = ap->ip->i_mount;

	struct xfs_perag	*pag;

	xfs_agnumber_t		ag, startag;

	int			notinit = 0;

	int			error;



	mp = ap->ip->i_mount;

	align = ap->userdata ? xfs_get_extsz_hint(ap->ip) : 0;

	if (unlikely(align)) {

		error = xfs_bmap_extsize_align(mp, ap->gotp, ap->prevp,

						align, 0, ap->eof, 0, ap->conv,

						&ap->off, &ap->alen);

		ASSERT(!error);

		ASSERT(ap->alen);

	}

	nullfb = ap->firstblock == NULLFSBLOCK;

	fb_agno = nullfb ? NULLAGNUMBER : XFS_FSB_TO_AGNO(mp, ap->firstblock);

	if (nullfb) {

		if (ap->userdata && xfs_inode_is_filestream(ap->ip)) {

			ag = xfs_filestream_lookup_ag(ap->ip);

			ag = (ag != NULLAGNUMBER) ? ag : 0;

			ap->rval = XFS_AGB_TO_FSB(mp, ag, 0);

		} else {

			ap->rval = XFS_INO_TO_FSB(mp, ap->ip->i_ino);

		}

	} else

		ap->rval = ap->firstblock;



	xfs_bmap_adjacent(ap);



	/*

	 * If allowed, use ap->rval; otherwise must use firstblock since

	 * it's in the right allocation group.

	 */

	if (nullfb || XFS_FSB_TO_AGNO(mp, ap->rval) == fb_agno)

		;

	else

		ap->rval = ap->firstblock;

	/*

	 * Normal allocation, done through xfs_alloc_vextent.

	 */

	tryagain = isaligned = 0;

	args.tp = ap->tp;

	args.mp = mp;

	args.fsbno = ap->rval;

	args.maxlen = MIN(ap->alen, mp->m_sb.sb_agblocks);

	args.firstblock = ap->firstblock;

	blen = 0;

	if (nullfb) {

	if (ap->userdata && xfs_inode_is_filestream(ap->ip))

			args.type = XFS_ALLOCTYPE_NEAR_BNO;

		args->type = XFS_ALLOCTYPE_NEAR_BNO;

	else

			args.type = XFS_ALLOCTYPE_START_BNO;

		args.total = ap->total;

		args->type = XFS_ALLOCTYPE_START_BNO;

	args->total = ap->total;



	/*

		 * Search for an allocation group with a single extent

		 * large enough for the request.

		 *

		 * If one isn't found, then adjust the minimum allocation

		 * size to the largest space found.

	 * Search for an allocation group with a single extent large enough

	 * for the request.  If one isn't found, then adjust the minimum

	 * allocation size to the largest space found.

	 */

		startag = ag = XFS_FSB_TO_AGNO(mp, args.fsbno);

	startag = ag = XFS_FSB_TO_AGNO(mp, args->fsbno);

	if (startag == NULLAGNUMBER)

		startag = ag = 0;

		notinit = 0;



	pag = xfs_perag_get(mp, ag);

		while (blen < ap->alen) {

			if (!pag->pagf_init &&

			    (error = xfs_alloc_pagf_init(mp, args.tp,

				    ag, XFS_ALLOC_FLAG_TRYLOCK))) {

	while (*blen < ap->alen) {

		if (!pag->pagf_init) {

			error = xfs_alloc_pagf_init(mp, args->tp, ag,

						    XFS_ALLOC_FLAG_TRYLOCK);

			if (error) {

				xfs_perag_put(pag);

				return error;

			}

		}



		/*

		 * See xfs_alloc_fix_freelist...

		 */

		if (pag->pagf_init) {

			xfs_extlen_t	longest;

			longest = xfs_alloc_longest_free_extent(mp, pag);

				if (blen < longest)

					blen = longest;

			if (*blen < longest)

				*blen = longest;

		} else

			notinit = 1;



		if (xfs_inode_is_filestream(ap->ip)) {

				if (blen >= ap->alen)

			if (*blen >= ap->alen)

				break;



			if (ap->userdata) {
@@ -2684,31 +2634,99 @@ xfs_bmap_btalloc( 
		pag = xfs_perag_get(mp, ag);

	}

	xfs_perag_put(pag);



	/*

	 * Since the above loop did a BUF_TRYLOCK, it is

	 * possible that there is space for this request.

	 */

		if (notinit || blen < ap->minlen)

			args.minlen = ap->minlen;

	if (notinit || *blen < ap->minlen)

		args->minlen = ap->minlen;

	/*

	 * If the best seen length is less than the request

	 * length, use the best as the minimum.

	 */

		else if (blen < ap->alen)

			args.minlen = blen;

	else if (*blen < ap->alen)

		args->minlen = *blen;

	/*

	 * Otherwise we've seen an extent as big as alen,

	 * use that as the minimum.

	 */

	else

			args.minlen = ap->alen;

		args->minlen = ap->alen;



	/*

	 * set the failure fallback case to look in the selected

	 * AG as the stream may have moved.

	 */

	if (xfs_inode_is_filestream(ap->ip))

			ap->rval = args.fsbno = XFS_AGB_TO_FSB(mp, ag, 0);

		ap->rval = args->fsbno = XFS_AGB_TO_FSB(mp, ag, 0);



	return 0;

}



STATIC int

xfs_bmap_btalloc(

	xfs_bmalloca_t	*ap)		/* bmap alloc argument struct */

{

	xfs_mount_t	*mp;		/* mount point structure */

	xfs_alloctype_t	atype = 0;	/* type for allocation routines */

	xfs_extlen_t	align;		/* minimum allocation alignment */

	xfs_agnumber_t	fb_agno;	/* ag number of ap->firstblock */

	xfs_agnumber_t	ag;

	xfs_alloc_arg_t	args;

	xfs_extlen_t	blen;

	xfs_extlen_t	nextminlen = 0;

	int		nullfb;		/* true if ap->firstblock isn't set */

	int		isaligned;

	int		tryagain;

	int		error;



	mp = ap->ip->i_mount;

	align = ap->userdata ? xfs_get_extsz_hint(ap->ip) : 0;

	if (unlikely(align)) {

		error = xfs_bmap_extsize_align(mp, ap->gotp, ap->prevp,

						align, 0, ap->eof, 0, ap->conv,

						&ap->off, &ap->alen);

		ASSERT(!error);

		ASSERT(ap->alen);

	}

	nullfb = ap->firstblock == NULLFSBLOCK;

	fb_agno = nullfb ? NULLAGNUMBER : XFS_FSB_TO_AGNO(mp, ap->firstblock);

	if (nullfb) {

		if (ap->userdata && xfs_inode_is_filestream(ap->ip)) {

			ag = xfs_filestream_lookup_ag(ap->ip);

			ag = (ag != NULLAGNUMBER) ? ag : 0;

			ap->rval = XFS_AGB_TO_FSB(mp, ag, 0);

		} else {

			ap->rval = XFS_INO_TO_FSB(mp, ap->ip->i_ino);

		}

	} else

		ap->rval = ap->firstblock;



	xfs_bmap_adjacent(ap);



	/*

	 * If allowed, use ap->rval; otherwise must use firstblock since

	 * it's in the right allocation group.

	 */

	if (nullfb || XFS_FSB_TO_AGNO(mp, ap->rval) == fb_agno)

		;

	else

		ap->rval = ap->firstblock;

	/*

	 * Normal allocation, done through xfs_alloc_vextent.

	 */

	tryagain = isaligned = 0;

	args.tp = ap->tp;

	args.mp = mp;

	args.fsbno = ap->rval;

	args.maxlen = MIN(ap->alen, mp->m_sb.sb_agblocks);

	args.firstblock = ap->firstblock;

	blen = 0;

	if (nullfb) {

		error = xfs_bmap_btalloc_nullfb(ap, &args, &blen);

		if (error)

			return error;

	} else if (ap->low) {

		if (xfs_inode_is_filestream(ap->ip))

			args.type = XFS_ALLOCTYPE_FIRST_AG;

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