On Thu, Mar 05, 2020 at 09:30:54AM -0500, Brian Foster wrote:
> On Tue, Mar 03, 2020 at 07:28:47PM -0800, Darrick J. Wong wrote:
> > From: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
> >
> > Add support for btree staging cursors for the per-AG btree types. This
> > is needed both for online repair and also to convert xfs_repair to use
> > btree bulk loading.
> >
> > Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
> > ---
> > fs/xfs/libxfs/xfs_alloc_btree.c | 99 +++++++++++++++++++++++++++++-------
> > fs/xfs/libxfs/xfs_alloc_btree.h | 7 +++
> > fs/xfs/libxfs/xfs_ialloc_btree.c | 84 +++++++++++++++++++++++++++----
> > fs/xfs/libxfs/xfs_ialloc_btree.h | 6 ++
> > fs/xfs/libxfs/xfs_refcount_btree.c | 69 +++++++++++++++++++++----
> > fs/xfs/libxfs/xfs_refcount_btree.h | 7 +++
> > fs/xfs/libxfs/xfs_rmap_btree.c | 66 ++++++++++++++++++++----
> > fs/xfs/libxfs/xfs_rmap_btree.h | 6 ++
> > 8 files changed, 295 insertions(+), 49 deletions(-)
> >
> >
> > diff --git a/fs/xfs/libxfs/xfs_alloc_btree.c b/fs/xfs/libxfs/xfs_alloc_btree.c
> > index 279694d73e4e..94dc18c8f9bc 100644
> > --- a/fs/xfs/libxfs/xfs_alloc_btree.c
> > +++ b/fs/xfs/libxfs/xfs_alloc_btree.c
> > @@ -471,6 +471,41 @@ static const struct xfs_btree_ops xfs_cntbt_ops = {
> > .recs_inorder = xfs_cntbt_recs_inorder,
> > };
> >
> > +/* Allocate most of a new allocation btree cursor. */
> > +STATIC struct xfs_btree_cur *
> > +xfs_allocbt_init_common(
> > + struct xfs_mount *mp,
> > + struct xfs_trans *tp,
> > + xfs_agnumber_t agno,
> > + xfs_btnum_t btnum)
> > +{
>
> Separate refactoring patches please.
Ok.
> > + struct xfs_btree_cur *cur;
> > +
> > + ASSERT(btnum == XFS_BTNUM_BNO || btnum == XFS_BTNUM_CNT);
> > +
> > + cur = kmem_zone_zalloc(xfs_btree_cur_zone, KM_NOFS);
> > +
> > + cur->bc_tp = tp;
> > + cur->bc_mp = mp;
> > + cur->bc_btnum = btnum;
> > + cur->bc_blocklog = mp->m_sb.sb_blocklog;
> > + cur->bc_private.a.agno = agno;
> > + cur->bc_private.a.priv.abt.active = false;
> > +
> > + if (btnum == XFS_BTNUM_CNT) {
> > + cur->bc_ops = &xfs_cntbt_ops;
> > + cur->bc_statoff = XFS_STATS_CALC_INDEX(xs_abtc_2);
> > + } else {
> > + cur->bc_ops = &xfs_bnobt_ops;
> > + cur->bc_statoff = XFS_STATS_CALC_INDEX(xs_abtb_2);
> > + }
> > +
> > + if (xfs_sb_version_hascrc(&mp->m_sb))
> > + cur->bc_flags |= XFS_BTREE_CRC_BLOCKS;
> > +
> > + return cur;
> > +}
> > +
> > /*
> > * Allocate a new allocation btree cursor.
> > */
> > @@ -485,36 +520,64 @@ xfs_allocbt_init_cursor(
> > struct xfs_agf *agf = XFS_BUF_TO_AGF(agbp);
> > struct xfs_btree_cur *cur;
> >
> > - ASSERT(btnum == XFS_BTNUM_BNO || btnum == XFS_BTNUM_CNT);
> > -
> > - cur = kmem_zone_zalloc(xfs_btree_cur_zone, KM_NOFS);
> > -
> > - cur->bc_tp = tp;
> > - cur->bc_mp = mp;
> > - cur->bc_btnum = btnum;
> > - cur->bc_blocklog = mp->m_sb.sb_blocklog;
> > -
> > + cur = xfs_allocbt_init_common(mp, tp, agno, btnum);
> > if (btnum == XFS_BTNUM_CNT) {
> > - cur->bc_statoff = XFS_STATS_CALC_INDEX(xs_abtc_2);
> > - cur->bc_ops = &xfs_cntbt_ops;
> > cur->bc_nlevels = be32_to_cpu(agf->agf_levels[XFS_BTNUM_CNT]);
> > - cur->bc_flags = XFS_BTREE_LASTREC_UPDATE;
> > + cur->bc_flags |= XFS_BTREE_LASTREC_UPDATE;
> > } else {
> > - cur->bc_statoff = XFS_STATS_CALC_INDEX(xs_abtb_2);
> > - cur->bc_ops = &xfs_bnobt_ops;
> > cur->bc_nlevels = be32_to_cpu(agf->agf_levels[XFS_BTNUM_BNO]);
> > }
> >
> > cur->bc_private.a.agbp = agbp;
> > - cur->bc_private.a.agno = agno;
> > - cur->bc_private.a.priv.abt.active = false;
> >
> > - if (xfs_sb_version_hascrc(&mp->m_sb))
> > - cur->bc_flags |= XFS_BTREE_CRC_BLOCKS;
> > + return cur;
> > +}
> >
> > +/* Create a free space btree cursor with a fake root for staging. */
> > +struct xfs_btree_cur *
> > +xfs_allocbt_stage_cursor(
> > + struct xfs_mount *mp,
> > + struct xfs_trans *tp,
> > + struct xbtree_afakeroot *afake,
> > + xfs_agnumber_t agno,
> > + xfs_btnum_t btnum)
> > +{
> > + struct xfs_btree_cur *cur;
> > +
> > + cur = xfs_allocbt_init_common(mp, tp, agno, btnum);
> > + if (btnum == XFS_BTNUM_BNO)
> > + xfs_btree_stage_afakeroot(cur, afake, NULL);
> > + else
> > + xfs_btree_stage_afakeroot(cur, afake, NULL);
>
> Looks like the same function call in either case..? I think I saw that
> in one or two other spots glancing through the rest as well, btw.
Yeah, I think this is a leftover from a previous refactoring. Will fix.
> Otherwise the rest looks mostly boilerplate. I'd just repeat the same
> comment as above with regard to separating out refactoring. I also think
> an enablement patch per btree implementation might be preferable to
> enabling a bunch of trees in one patch.
<nod> Thanks for reviewing!
> Brian
>
> > return cur;
> > }
> >
> > +/*
> > + * Install a new free space btree root. Caller is responsible for invalidating
> > + * and freeing the old btree blocks.
> > + */
> > +void
> > +xfs_allocbt_commit_staged_btree(
> > + struct xfs_btree_cur *cur,
> > + struct xfs_buf *agbp)
> > +{
> > + struct xfs_agf *agf = XFS_BUF_TO_AGF(agbp);
> > + struct xbtree_afakeroot *afake = cur->bc_private.a.afake;
> > +
> > + ASSERT(cur->bc_flags & XFS_BTREE_STAGING);
> > +
> > + agf->agf_roots[cur->bc_btnum] = cpu_to_be32(afake->af_root);
> > + agf->agf_levels[cur->bc_btnum] = cpu_to_be32(afake->af_levels);
> > + xfs_alloc_log_agf(cur->bc_tp, agbp, XFS_AGF_ROOTS | XFS_AGF_LEVELS);
> > +
> > + if (cur->bc_btnum == XFS_BTNUM_BNO) {
> > + xfs_btree_commit_afakeroot(cur, agbp, &xfs_bnobt_ops);
> > + } else {
> > + cur->bc_flags |= XFS_BTREE_LASTREC_UPDATE;
> > + xfs_btree_commit_afakeroot(cur, agbp, &xfs_cntbt_ops);
> > + }
> > +}
> > +
> > /*
> > * Calculate number of records in an alloc btree block.
> > */
> > diff --git a/fs/xfs/libxfs/xfs_alloc_btree.h b/fs/xfs/libxfs/xfs_alloc_btree.h
> > index c9305ebb69f6..dde324609a89 100644
> > --- a/fs/xfs/libxfs/xfs_alloc_btree.h
> > +++ b/fs/xfs/libxfs/xfs_alloc_btree.h
> > @@ -13,6 +13,7 @@
> > struct xfs_buf;
> > struct xfs_btree_cur;
> > struct xfs_mount;
> > +struct xbtree_afakeroot;
> >
> > /*
> > * Btree block header size depends on a superblock flag.
> > @@ -48,8 +49,14 @@ struct xfs_mount;
> > extern struct xfs_btree_cur *xfs_allocbt_init_cursor(struct xfs_mount *,
> > struct xfs_trans *, struct xfs_buf *,
> > xfs_agnumber_t, xfs_btnum_t);
> > +struct xfs_btree_cur *xfs_allocbt_stage_cursor(struct xfs_mount *mp,
> > + struct xfs_trans *tp, struct xbtree_afakeroot *afake,
> > + xfs_agnumber_t agno, xfs_btnum_t btnum);
> > extern int xfs_allocbt_maxrecs(struct xfs_mount *, int, int);
> > extern xfs_extlen_t xfs_allocbt_calc_size(struct xfs_mount *mp,
> > unsigned long long len);
> >
> > +void xfs_allocbt_commit_staged_btree(struct xfs_btree_cur *cur,
> > + struct xfs_buf *agbp);
> > +
> > #endif /* __XFS_ALLOC_BTREE_H__ */
> > diff --git a/fs/xfs/libxfs/xfs_ialloc_btree.c b/fs/xfs/libxfs/xfs_ialloc_btree.c
> > index b82992f795aa..15d8ec692a6e 100644
> > --- a/fs/xfs/libxfs/xfs_ialloc_btree.c
> > +++ b/fs/xfs/libxfs/xfs_ialloc_btree.c
> > @@ -400,32 +400,27 @@ static const struct xfs_btree_ops xfs_finobt_ops = {
> > };
> >
> > /*
> > - * Allocate a new inode btree cursor.
> > + * Initialize a new inode btree cursor.
> > */
> > -struct xfs_btree_cur * /* new inode btree cursor */
> > -xfs_inobt_init_cursor(
> > +static struct xfs_btree_cur *
> > +xfs_inobt_init_common(
> > struct xfs_mount *mp, /* file system mount point */
> > struct xfs_trans *tp, /* transaction pointer */
> > - struct xfs_buf *agbp, /* buffer for agi structure */
> > xfs_agnumber_t agno, /* allocation group number */
> > xfs_btnum_t btnum) /* ialloc or free ino btree */
> > {
> > - struct xfs_agi *agi = XFS_BUF_TO_AGI(agbp);
> > struct xfs_btree_cur *cur;
> >
> > cur = kmem_zone_zalloc(xfs_btree_cur_zone, KM_NOFS);
> > -
> > cur->bc_tp = tp;
> > cur->bc_mp = mp;
> > cur->bc_btnum = btnum;
> > if (btnum == XFS_BTNUM_INO) {
> > - cur->bc_nlevels = be32_to_cpu(agi->agi_level);
> > - cur->bc_ops = &xfs_inobt_ops;
> > cur->bc_statoff = XFS_STATS_CALC_INDEX(xs_ibt_2);
> > + cur->bc_ops = &xfs_inobt_ops;
> > } else {
> > - cur->bc_nlevels = be32_to_cpu(agi->agi_free_level);
> > - cur->bc_ops = &xfs_finobt_ops;
> > cur->bc_statoff = XFS_STATS_CALC_INDEX(xs_fibt_2);
> > + cur->bc_ops = &xfs_finobt_ops;
> > }
> >
> > cur->bc_blocklog = mp->m_sb.sb_blocklog;
> > @@ -433,12 +428,79 @@ xfs_inobt_init_cursor(
> > if (xfs_sb_version_hascrc(&mp->m_sb))
> > cur->bc_flags |= XFS_BTREE_CRC_BLOCKS;
> >
> > - cur->bc_private.a.agbp = agbp;
> > cur->bc_private.a.agno = agno;
> > + return cur;
> > +}
> >
> > +/* Create an inode btree cursor. */
> > +struct xfs_btree_cur *
> > +xfs_inobt_init_cursor(
> > + struct xfs_mount *mp,
> > + struct xfs_trans *tp,
> > + struct xfs_buf *agbp,
> > + xfs_agnumber_t agno,
> > + xfs_btnum_t btnum)
> > +{
> > + struct xfs_btree_cur *cur;
> > + struct xfs_agi *agi = XFS_BUF_TO_AGI(agbp);
> > +
> > + cur = xfs_inobt_init_common(mp, tp, agno, btnum);
> > + if (btnum == XFS_BTNUM_INO)
> > + cur->bc_nlevels = be32_to_cpu(agi->agi_level);
> > + else
> > + cur->bc_nlevels = be32_to_cpu(agi->agi_free_level);
> > + cur->bc_private.a.agbp = agbp;
> > return cur;
> > }
> >
> > +/* Create an inode btree cursor with a fake root for staging. */
> > +struct xfs_btree_cur *
> > +xfs_inobt_stage_cursor(
> > + struct xfs_mount *mp,
> > + struct xfs_trans *tp,
> > + struct xbtree_afakeroot *afake,
> > + xfs_agnumber_t agno,
> > + xfs_btnum_t btnum)
> > +{
> > + struct xfs_btree_cur *cur;
> > +
> > + cur = xfs_inobt_init_common(mp, tp, agno, btnum);
> > + if (btnum == XFS_BTNUM_INO)
> > + xfs_btree_stage_afakeroot(cur, afake, NULL);
> > + else
> > + xfs_btree_stage_afakeroot(cur, afake, NULL);
> > + return cur;
> > +}
> > +
> > +/*
> > + * Install a new inobt btree root. Caller is responsible for invalidating
> > + * and freeing the old btree blocks.
> > + */
> > +void
> > +xfs_inobt_commit_staged_btree(
> > + struct xfs_btree_cur *cur,
> > + struct xfs_buf *agbp)
> > +{
> > + struct xfs_agi *agi = XFS_BUF_TO_AGI(agbp);
> > + struct xbtree_afakeroot *afake = cur->bc_private.a.afake;
> > +
> > + ASSERT(cur->bc_flags & XFS_BTREE_STAGING);
> > +
> > + if (cur->bc_btnum == XFS_BTNUM_INO) {
> > + agi->agi_root = cpu_to_be32(afake->af_root);
> > + agi->agi_level = cpu_to_be32(afake->af_levels);
> > + xfs_ialloc_log_agi(cur->bc_tp, agbp, XFS_AGI_ROOT |
> > + XFS_AGI_LEVEL);
> > + xfs_btree_commit_afakeroot(cur, agbp, &xfs_inobt_ops);
> > + } else {
> > + agi->agi_free_root = cpu_to_be32(afake->af_root);
> > + agi->agi_free_level = cpu_to_be32(afake->af_levels);
> > + xfs_ialloc_log_agi(cur->bc_tp, agbp, XFS_AGI_FREE_ROOT |
> > + XFS_AGI_FREE_LEVEL);
> > + xfs_btree_commit_afakeroot(cur, agbp, &xfs_finobt_ops);
> > + }
> > +}
> > +
> > /*
> > * Calculate number of records in an inobt btree block.
> > */
> > diff --git a/fs/xfs/libxfs/xfs_ialloc_btree.h b/fs/xfs/libxfs/xfs_ialloc_btree.h
> > index 951305ecaae1..9265b3e08c69 100644
> > --- a/fs/xfs/libxfs/xfs_ialloc_btree.h
> > +++ b/fs/xfs/libxfs/xfs_ialloc_btree.h
> > @@ -48,6 +48,9 @@ struct xfs_mount;
> > extern struct xfs_btree_cur *xfs_inobt_init_cursor(struct xfs_mount *,
> > struct xfs_trans *, struct xfs_buf *, xfs_agnumber_t,
> > xfs_btnum_t);
> > +struct xfs_btree_cur *xfs_inobt_stage_cursor(struct xfs_mount *mp,
> > + struct xfs_trans *tp, struct xbtree_afakeroot *afake,
> > + xfs_agnumber_t agno, xfs_btnum_t btnum);
> > extern int xfs_inobt_maxrecs(struct xfs_mount *, int, int);
> >
> > /* ir_holemask to inode allocation bitmap conversion */
> > @@ -68,4 +71,7 @@ int xfs_inobt_cur(struct xfs_mount *mp, struct xfs_trans *tp,
> > xfs_agnumber_t agno, xfs_btnum_t btnum,
> > struct xfs_btree_cur **curpp, struct xfs_buf **agi_bpp);
> >
> > +void xfs_inobt_commit_staged_btree(struct xfs_btree_cur *cur,
> > + struct xfs_buf *agbp);
> > +
> > #endif /* __XFS_IALLOC_BTREE_H__ */
> > diff --git a/fs/xfs/libxfs/xfs_refcount_btree.c b/fs/xfs/libxfs/xfs_refcount_btree.c
> > index 38529dbacd55..9034b40bd5cf 100644
> > --- a/fs/xfs/libxfs/xfs_refcount_btree.c
> > +++ b/fs/xfs/libxfs/xfs_refcount_btree.c
> > @@ -311,41 +311,90 @@ static const struct xfs_btree_ops xfs_refcountbt_ops = {
> > };
> >
> > /*
> > - * Allocate a new refcount btree cursor.
> > + * Initialize a new refcount btree cursor.
> > */
> > -struct xfs_btree_cur *
> > -xfs_refcountbt_init_cursor(
> > +static struct xfs_btree_cur *
> > +xfs_refcountbt_init_common(
> > struct xfs_mount *mp,
> > struct xfs_trans *tp,
> > - struct xfs_buf *agbp,
> > xfs_agnumber_t agno)
> > {
> > - struct xfs_agf *agf = XFS_BUF_TO_AGF(agbp);
> > struct xfs_btree_cur *cur;
> >
> > ASSERT(agno != NULLAGNUMBER);
> > ASSERT(agno < mp->m_sb.sb_agcount);
> > - cur = kmem_zone_zalloc(xfs_btree_cur_zone, KM_NOFS);
> >
> > + cur = kmem_zone_zalloc(xfs_btree_cur_zone, KM_NOFS);
> > cur->bc_tp = tp;
> > cur->bc_mp = mp;
> > cur->bc_btnum = XFS_BTNUM_REFC;
> > cur->bc_blocklog = mp->m_sb.sb_blocklog;
> > - cur->bc_ops = &xfs_refcountbt_ops;
> > cur->bc_statoff = XFS_STATS_CALC_INDEX(xs_refcbt_2);
> >
> > - cur->bc_nlevels = be32_to_cpu(agf->agf_refcount_level);
> > -
> > - cur->bc_private.a.agbp = agbp;
> > cur->bc_private.a.agno = agno;
> > cur->bc_flags |= XFS_BTREE_CRC_BLOCKS;
> >
> > cur->bc_private.a.priv.refc.nr_ops = 0;
> > cur->bc_private.a.priv.refc.shape_changes = 0;
> > + cur->bc_ops = &xfs_refcountbt_ops;
> > + return cur;
> > +}
> > +
> > +/* Create a btree cursor. */
> > +struct xfs_btree_cur *
> > +xfs_refcountbt_init_cursor(
> > + struct xfs_mount *mp,
> > + struct xfs_trans *tp,
> > + struct xfs_buf *agbp,
> > + xfs_agnumber_t agno)
> > +{
> > + struct xfs_agf *agf = XFS_BUF_TO_AGF(agbp);
> > + struct xfs_btree_cur *cur;
> >
> > + cur = xfs_refcountbt_init_common(mp, tp, agno);
> > + cur->bc_nlevels = be32_to_cpu(agf->agf_refcount_level);
> > + cur->bc_private.a.agbp = agbp;
> > return cur;
> > }
> >
> > +/* Create a btree cursor with a fake root for staging. */
> > +struct xfs_btree_cur *
> > +xfs_refcountbt_stage_cursor(
> > + struct xfs_mount *mp,
> > + struct xfs_trans *tp,
> > + struct xbtree_afakeroot *afake,
> > + xfs_agnumber_t agno)
> > +{
> > + struct xfs_btree_cur *cur;
> > +
> > + cur = xfs_refcountbt_init_common(mp, tp, agno);
> > + xfs_btree_stage_afakeroot(cur, afake, NULL);
> > + return cur;
> > +}
> > +
> > +/*
> > + * Swap in the new btree root. Once we pass this point the newly rebuilt btree
> > + * is in place and we have to kill off all the old btree blocks.
> > + */
> > +void
> > +xfs_refcountbt_commit_staged_btree(
> > + struct xfs_btree_cur *cur,
> > + struct xfs_buf *agbp)
> > +{
> > + struct xfs_agf *agf = XFS_BUF_TO_AGF(agbp);
> > + struct xbtree_afakeroot *afake = cur->bc_private.a.afake;
> > +
> > + ASSERT(cur->bc_flags & XFS_BTREE_STAGING);
> > +
> > + agf->agf_refcount_root = cpu_to_be32(afake->af_root);
> > + agf->agf_refcount_level = cpu_to_be32(afake->af_levels);
> > + agf->agf_refcount_blocks = cpu_to_be32(afake->af_blocks);
> > + xfs_alloc_log_agf(cur->bc_tp, agbp, XFS_AGF_REFCOUNT_BLOCKS |
> > + XFS_AGF_REFCOUNT_ROOT |
> > + XFS_AGF_REFCOUNT_LEVEL);
> > + xfs_btree_commit_afakeroot(cur, agbp, &xfs_refcountbt_ops);
> > +}
> > +
> > /*
> > * Calculate the number of records in a refcount btree block.
> > */
> > diff --git a/fs/xfs/libxfs/xfs_refcount_btree.h b/fs/xfs/libxfs/xfs_refcount_btree.h
> > index ba416f71c824..978b714be9f4 100644
> > --- a/fs/xfs/libxfs/xfs_refcount_btree.h
> > +++ b/fs/xfs/libxfs/xfs_refcount_btree.h
> > @@ -13,6 +13,7 @@
> > struct xfs_buf;
> > struct xfs_btree_cur;
> > struct xfs_mount;
> > +struct xbtree_afakeroot;
> >
> > /*
> > * Btree block header size
> > @@ -46,6 +47,9 @@ struct xfs_mount;
> > extern struct xfs_btree_cur *xfs_refcountbt_init_cursor(struct xfs_mount *mp,
> > struct xfs_trans *tp, struct xfs_buf *agbp,
> > xfs_agnumber_t agno);
> > +struct xfs_btree_cur *xfs_refcountbt_stage_cursor(struct xfs_mount *mp,
> > + struct xfs_trans *tp, struct xbtree_afakeroot *afake,
> > + xfs_agnumber_t agno);
> > extern int xfs_refcountbt_maxrecs(int blocklen, bool leaf);
> > extern void xfs_refcountbt_compute_maxlevels(struct xfs_mount *mp);
> >
> > @@ -58,4 +62,7 @@ extern int xfs_refcountbt_calc_reserves(struct xfs_mount *mp,
> > struct xfs_trans *tp, xfs_agnumber_t agno, xfs_extlen_t *ask,
> > xfs_extlen_t *used);
> >
> > +void xfs_refcountbt_commit_staged_btree(struct xfs_btree_cur *cur,
> > + struct xfs_buf *agbp);
> > +
> > #endif /* __XFS_REFCOUNT_BTREE_H__ */
> > diff --git a/fs/xfs/libxfs/xfs_rmap_btree.c b/fs/xfs/libxfs/xfs_rmap_btree.c
> > index fc78efa52c94..062aeaaa7a8c 100644
> > --- a/fs/xfs/libxfs/xfs_rmap_btree.c
> > +++ b/fs/xfs/libxfs/xfs_rmap_btree.c
> > @@ -448,17 +448,12 @@ static const struct xfs_btree_ops xfs_rmapbt_ops = {
> > .recs_inorder = xfs_rmapbt_recs_inorder,
> > };
> >
> > -/*
> > - * Allocate a new allocation btree cursor.
> > - */
> > -struct xfs_btree_cur *
> > -xfs_rmapbt_init_cursor(
> > +static struct xfs_btree_cur *
> > +xfs_rmapbt_init_common(
> > struct xfs_mount *mp,
> > struct xfs_trans *tp,
> > - struct xfs_buf *agbp,
> > xfs_agnumber_t agno)
> > {
> > - struct xfs_agf *agf = XFS_BUF_TO_AGF(agbp);
> > struct xfs_btree_cur *cur;
> >
> > cur = kmem_zone_zalloc(xfs_btree_cur_zone, KM_NOFS);
> > @@ -468,16 +463,67 @@ xfs_rmapbt_init_cursor(
> > cur->bc_btnum = XFS_BTNUM_RMAP;
> > cur->bc_flags = XFS_BTREE_CRC_BLOCKS | XFS_BTREE_OVERLAPPING;
> > cur->bc_blocklog = mp->m_sb.sb_blocklog;
> > - cur->bc_ops = &xfs_rmapbt_ops;
> > - cur->bc_nlevels = be32_to_cpu(agf->agf_levels[XFS_BTNUM_RMAP]);
> > cur->bc_statoff = XFS_STATS_CALC_INDEX(xs_rmap_2);
> > + cur->bc_private.a.agno = agno;
> > + cur->bc_ops = &xfs_rmapbt_ops;
> >
> > + return cur;
> > +}
> > +
> > +/* Create a new reverse mapping btree cursor. */
> > +struct xfs_btree_cur *
> > +xfs_rmapbt_init_cursor(
> > + struct xfs_mount *mp,
> > + struct xfs_trans *tp,
> > + struct xfs_buf *agbp,
> > + xfs_agnumber_t agno)
> > +{
> > + struct xfs_agf *agf = XFS_BUF_TO_AGF(agbp);
> > + struct xfs_btree_cur *cur;
> > +
> > + cur = xfs_rmapbt_init_common(mp, tp, agno);
> > + cur->bc_nlevels = be32_to_cpu(agf->agf_levels[XFS_BTNUM_RMAP]);
> > cur->bc_private.a.agbp = agbp;
> > - cur->bc_private.a.agno = agno;
> > + return cur;
> > +}
> > +
> > +/* Create a new reverse mapping btree cursor with a fake root for staging. */
> > +struct xfs_btree_cur *
> > +xfs_rmapbt_stage_cursor(
> > + struct xfs_mount *mp,
> > + struct xfs_trans *tp,
> > + struct xbtree_afakeroot *afake,
> > + xfs_agnumber_t agno)
> > +{
> > + struct xfs_btree_cur *cur;
> >
> > + cur = xfs_rmapbt_init_common(mp, tp, agno);
> > + xfs_btree_stage_afakeroot(cur, afake, NULL);
> > return cur;
> > }
> >
> > +/*
> > + * Install a new reverse mapping btree root. Caller is responsible for
> > + * invalidating and freeing the old btree blocks.
> > + */
> > +void
> > +xfs_rmapbt_commit_staged_btree(
> > + struct xfs_btree_cur *cur,
> > + struct xfs_buf *agbp)
> > +{
> > + struct xfs_agf *agf = XFS_BUF_TO_AGF(agbp);
> > + struct xbtree_afakeroot *afake = cur->bc_private.a.afake;
> > +
> > + ASSERT(cur->bc_flags & XFS_BTREE_STAGING);
> > +
> > + agf->agf_roots[cur->bc_btnum] = cpu_to_be32(afake->af_root);
> > + agf->agf_levels[cur->bc_btnum] = cpu_to_be32(afake->af_levels);
> > + agf->agf_rmap_blocks = cpu_to_be32(afake->af_blocks);
> > + xfs_alloc_log_agf(cur->bc_tp, agbp, XFS_AGF_ROOTS | XFS_AGF_LEVELS |
> > + XFS_AGF_RMAP_BLOCKS);
> > + xfs_btree_commit_afakeroot(cur, agbp, &xfs_rmapbt_ops);
> > +}
> > +
> > /*
> > * Calculate number of records in an rmap btree block.
> > */
> > diff --git a/fs/xfs/libxfs/xfs_rmap_btree.h b/fs/xfs/libxfs/xfs_rmap_btree.h
> > index 820d668b063d..c6785c7851a8 100644
> > --- a/fs/xfs/libxfs/xfs_rmap_btree.h
> > +++ b/fs/xfs/libxfs/xfs_rmap_btree.h
> > @@ -9,6 +9,7 @@
> > struct xfs_buf;
> > struct xfs_btree_cur;
> > struct xfs_mount;
> > +struct xbtree_afakeroot;
> >
> > /* rmaps only exist on crc enabled filesystems */
> > #define XFS_RMAP_BLOCK_LEN XFS_BTREE_SBLOCK_CRC_LEN
> > @@ -43,6 +44,11 @@ struct xfs_mount;
> > struct xfs_btree_cur *xfs_rmapbt_init_cursor(struct xfs_mount *mp,
> > struct xfs_trans *tp, struct xfs_buf *bp,
> > xfs_agnumber_t agno);
> > +struct xfs_btree_cur *xfs_rmapbt_stage_cursor(struct xfs_mount *mp,
> > + struct xfs_trans *tp, struct xbtree_afakeroot *afake,
> > + xfs_agnumber_t agno);
> > +void xfs_rmapbt_commit_staged_btree(struct xfs_btree_cur *cur,
> > + struct xfs_buf *agbp);
> > int xfs_rmapbt_maxrecs(int blocklen, int leaf);
> > extern void xfs_rmapbt_compute_maxlevels(struct xfs_mount *mp);
> >
> >
>
