xfs: add support for refcount btree staging cursors

Add support for btree staging cursors for the refcount btrees.  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@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>

diff --git a/fs/xfs/libxfs/xfs_refcount_btree.c b/fs/xfs/libxfs/xfs_refcount_btree.c
index e07a2c4..7fd6044 100644 (file)
--- a/fs/xfs/libxfs/xfs_refcount_btree.c
+++ b/fs/xfs/libxfs/xfs_refcount_btree.c
@@ -12,6 +12,7 @@
 #include "xfs_sb.h"
 #include "xfs_mount.h"
 #include "xfs_btree.h"
+#include "xfs_btree_staging.h"
 #include "xfs_refcount_btree.h"
 #include "xfs_alloc.h"
 #include "xfs_error.h"
@@ -311,42 +312,91 @@ 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 = agbp->b_addr;
        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_ag.agbp = agbp;
        cur->bc_ag.agno = agno;
        cur->bc_flags |= XFS_BTREE_CRC_BLOCKS;
 
        cur->bc_ag.refc.nr_ops = 0;
        cur->bc_ag.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 = agbp->b_addr;
+       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_ag.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 xbtree_afakeroot *afake,
+       xfs_agnumber_t          agno)
+{
+       struct xfs_btree_cur    *cur;
 
+       cur = xfs_refcountbt_init_common(mp, NULL, agno);
+       xfs_btree_stage_afakeroot(cur, afake);
        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_trans        *tp,
+       struct xfs_buf          *agbp)
+{
+       struct xfs_agf          *agf = agbp->b_addr;
+       struct xbtree_afakeroot *afake = cur->bc_ag.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(tp, agbp, XFS_AGF_REFCOUNT_BLOCKS |
+                                   XFS_AGF_REFCOUNT_ROOT |
+                                   XFS_AGF_REFCOUNT_LEVEL);
+       xfs_btree_commit_afakeroot(cur, tp, agbp, &xfs_refcountbt_ops);
+}
+
+/*
  * Calculate the number of records in a refcount btree block.
  */
 int

diff --git a/fs/xfs/libxfs/xfs_refcount_btree.h b/fs/xfs/libxfs/xfs_refcount_btree.h
index ba416f7..69dc515 100644 (file)
--- 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 +47,8 @@ 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 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 +61,7 @@ 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_trans *tp, struct xfs_buf *agbp);
+
 #endif /* __XFS_REFCOUNT_BTREE_H__ */