xfs: refcover CoW leftovers in the realtime volume

Scan the realtime refcount tree at mount time to get rid of leftover
CoW staging extents.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>

3 files changed, 65 insertions, 17 deletions

diff --git a/fs/xfs/libxfs/xfs_refcount.c b/fs/xfs/libxfs/xfs_refcount.c
index 75b5a033fb43..b0b671650c68 100644
--- a/fs/xfs/libxfs/xfs_refcount.c
+++ b/fs/xfs/libxfs/xfs_refcount.c
@@ -1923,14 +1923,15 @@ xfs_refcount_recover_extent(
 }
 
 /* Find and remove leftover CoW reservations. */
-int
-xfs_refcount_recover_cow_leftovers(
+static int
+xfs_refcount_recover_group_cow_leftovers(
 	struct xfs_mount		*mp,
-	struct xfs_perag		*pag)
+	struct xfs_perag		*pag,
+	struct xfs_rtgroup		*rtg)
 {
 	struct xfs_trans		*tp;
 	struct xfs_btree_cur		*cur;
-	struct xfs_buf			*agbp;
+	struct xfs_buf			*agbp = NULL;
 	struct xfs_refcount_recovery	*rr, *n;
 	struct list_head		debris;
 	union xfs_btree_irec		low;
@@ -1940,7 +1941,12 @@ xfs_refcount_recover_cow_leftovers(
 
 	/* reflink filesystems mustn't have AGs larger than 2^31-1 blocks */
 	BUILD_BUG_ON(XFS_MAX_CRC_AG_BLOCKS >= XFS_REFC_COWFLAG);
-	if (mp->m_sb.sb_agblocks > XFS_MAX_CRC_AG_BLOCKS)
+	if (pag && mp->m_sb.sb_agblocks > XFS_MAX_CRC_AG_BLOCKS)
+		return -EOPNOTSUPP;
+
+	/* rtreflink filesystems can't have rtgroups larger than 2^31-1 blocks */
+	BUILD_BUG_ON(XFS_MAX_RGBLOCKS >= XFS_REFC_COWFLAG);
+	if (rtg && mp->m_sb.sb_rgblocks >= XFS_MAX_RGBLOCKS)
 		return -EOPNOTSUPP;
 
 	INIT_LIST_HEAD(&debris);
@@ -1959,10 +1965,16 @@ xfs_refcount_recover_cow_leftovers(
 	if (error)
 		return error;
 
-	error = xfs_alloc_read_agf(pag, tp, 0, &agbp);
-	if (error)
-		goto out_trans;
-	cur = xfs_refcountbt_init_cursor(mp, tp, agbp, pag);
+	if (rtg) {
+		xfs_rtgroup_lock(NULL, rtg, XFS_RTGLOCK_REFCOUNT);
+		cur = xfs_rtrefcountbt_init_cursor(mp, tp, rtg,
+				rtg->rtg_refcountip);
+	} else {
+		error = xfs_alloc_read_agf(pag, tp, 0, &agbp);
+		if (error)
+			goto out_trans;
+		cur = xfs_refcountbt_init_cursor(mp, tp, agbp, pag);
+	}
 
 	/* Find all the leftover CoW staging extents. */
 	memset(&low, 0, sizeof(low));
@@ -1972,7 +1984,10 @@ xfs_refcount_recover_cow_leftovers(
 	error = xfs_btree_query_range(cur, &low, &high,
 			xfs_refcount_recover_extent, &debris);
 	xfs_btree_del_cursor(cur, error);
-	xfs_trans_brelse(tp, agbp);
+	if (agbp)
+		xfs_trans_brelse(tp, agbp);
+	else
+		xfs_rtgroup_unlock(rtg, XFS_RTGLOCK_REFCOUNT);
 	xfs_trans_cancel(tp);
 	if (error)
 		goto out_free;
@@ -1985,14 +2000,18 @@ xfs_refcount_recover_cow_leftovers(
 			goto out_free;
 
 		/* Free the orphan record */
-		fsb = XFS_AGB_TO_FSB(mp, pag->pag_agno,
-				rr->rr_rrec.rc_startblock);
-		xfs_refcount_free_cow_extent(tp, false, fsb,
+		if (rtg)
+			fsb = xfs_rgbno_to_rtb(mp, rtg->rtg_rgno,
+					rr->rr_rrec.rc_startblock);
+		else
+			fsb = XFS_AGB_TO_FSB(mp, pag->pag_agno,
+					rr->rr_rrec.rc_startblock);
+		xfs_refcount_free_cow_extent(tp, rtg != NULL, fsb,
 				rr->rr_rrec.rc_blockcount);
 
 		/* Free the block. */
 		xfs_free_extent_later(tp, fsb, rr->rr_rrec.rc_blockcount, NULL,
-				0);
+				rtg != NULL ? XFS_FREE_EXTENT_REALTIME : 0);
 
 		error = xfs_trans_commit(tp);
 		if (error)
@@ -2014,6 +2033,22 @@ out_free:
 	return error;
 }
 
+int
+xfs_refcount_recover_cow_leftovers(
+	struct xfs_mount		*mp,
+	struct xfs_perag		*pag)
+{
+	return xfs_refcount_recover_group_cow_leftovers(mp, pag, NULL);
+}
+
+int
+xfs_refcount_recover_rtcow_leftovers(
+	struct xfs_mount		*mp,
+	struct xfs_rtgroup		*rtg)
+{
+	return xfs_refcount_recover_group_cow_leftovers(mp, NULL, rtg);
+}
+
 /*
  * Scan part of the keyspace of the refcount records and tell us if the area
  * has no records, is fully mapped by records, or is partially filled.
diff --git a/fs/xfs/libxfs/xfs_refcount.h b/fs/xfs/libxfs/xfs_refcount.h
index 4e725d723e88..c7907119d10c 100644
--- a/fs/xfs/libxfs/xfs_refcount.h
+++ b/fs/xfs/libxfs/xfs_refcount.h
@@ -12,6 +12,7 @@ struct xfs_perag;
 struct xfs_btree_cur;
 struct xfs_bmbt_irec;
 struct xfs_refcount_irec;
+struct xfs_rtgroup;
 
 extern int xfs_refcount_lookup_le(struct xfs_btree_cur *cur,
 		enum xfs_refc_domain domain, xfs_agblock_t bno, int *stat);
@@ -99,8 +100,10 @@ void xfs_refcount_alloc_cow_extent(struct xfs_trans *tp, bool isrt,
 		xfs_fsblock_t fsb, xfs_extlen_t len);
 void xfs_refcount_free_cow_extent(struct xfs_trans *tp, bool isrt,
 		xfs_fsblock_t fsb, xfs_extlen_t len);
-extern int xfs_refcount_recover_cow_leftovers(struct xfs_mount *mp,
+int xfs_refcount_recover_cow_leftovers(struct xfs_mount *mp,
 		struct xfs_perag *pag);
+int xfs_refcount_recover_rtcow_leftovers(struct xfs_mount *mp,
+		struct xfs_rtgroup *rtg);
 
 /*
  * While we're adjusting the refcounts records of an extent, we have
diff --git a/fs/xfs/xfs_reflink.c b/fs/xfs/xfs_reflink.c
index b88cabc4faba..80ebd4961df8 100644
--- a/fs/xfs/xfs_reflink.c
+++ b/fs/xfs/xfs_reflink.c
@@ -1004,7 +1004,9 @@ xfs_reflink_recover_cow(
 	struct xfs_mount	*mp)
 {
 	struct xfs_perag	*pag;
+	struct xfs_rtgroup	*rtg;
 	xfs_agnumber_t		agno;
+	xfs_rgnumber_t		rgno;
 	int			error = 0;
 
 	if (!xfs_has_reflink(mp))
@@ -1014,11 +1016,19 @@ xfs_reflink_recover_cow(
 		error = xfs_refcount_recover_cow_leftovers(mp, pag);
 		if (error) {
 			xfs_perag_put(pag);
-			break;
+			return error;
 		}
 	}
 
-	return error;
+	for_each_rtgroup(mp, rgno, rtg) {
+		error = xfs_refcount_recover_rtcow_leftovers(mp, rtg);
+		if (error) {
+			xfs_rtgroup_put(rtg);
+			return error;
+		}
+	}
+
+	return 0;
 }
 
 /*