From 42d7bab041ea3556872f10d653281c9c48533bed Mon Sep 17 00:00:00 2001
From: Luke Shumaker <lukeshu@lukeshu.com>
Date: Sat, 16 Jul 2022 00:41:23 -0600
Subject: wip

---
 lib/btrfsprogs/btrfsinspect/scanforextents/csum.go      | 12 ++++++++----
 .../btrfsinspect/scanforextents/scanforextents.go       | 17 +++++++++++++----
 2 files changed, 21 insertions(+), 8 deletions(-)

(limited to 'lib/btrfsprogs/btrfsinspect')

diff --git a/lib/btrfsprogs/btrfsinspect/scanforextents/csum.go b/lib/btrfsprogs/btrfsinspect/scanforextents/csum.go
index 7944497..ec46833 100644
--- a/lib/btrfsprogs/btrfsinspect/scanforextents/csum.go
+++ b/lib/btrfsprogs/btrfsinspect/scanforextents/csum.go
@@ -100,7 +100,7 @@ func readCSumTree(ctx context.Context, fs btrfs.Trees) map[shortSum][]btrfsvol.L
 	return sum2laddrs
 }
 
-func LookupCSum(fs btrfs.Trees, alg btrfssum.CSumType, laddr btrfsvol.LogicalAddr) (btrfssum.CSum, error) {
+func LookupCSum(fs btrfs.Trees, alg btrfssum.CSumType, laddr btrfsvol.LogicalAddr) (map[btrfsvol.LogicalAddr]btrfssum.CSum, error) {
 	item, err := fs.TreeSearch(btrfs.CSUM_TREE_OBJECTID, func(key btrfs.Key, size uint32) int {
 		itemBeg := btrfsvol.LogicalAddr(key.ObjectID)
 		numSums := int64(size) / int64(alg.Size())
@@ -115,11 +115,15 @@ func LookupCSum(fs btrfs.Trees, alg btrfssum.CSumType, laddr btrfsvol.LogicalAdd
 		}
 	})
 	if err != nil {
-		return btrfssum.CSum{}, err
+		return nil, err
 	}
 	body, ok := item.Body.(btrfsitem.ExtentCSum)
 	if !ok {
-		return btrfssum.CSum{}, fmt.Errorf("item body is %T not ExtentCSum", item.Body)
+		return nil, fmt.Errorf("item body is %T not ExtentCSum", item.Body)
+	}
+	ret := make(map[btrfsvol.LogicalAddr]btrfssum.CSum, len(body.Sums))
+	for i, sum := range body.Sums {
+		ret[btrfsvol.LogicalAddr(item.Key.ObjectID)+(btrfsvol.LogicalAddr(i)*csumBlockSize)] = sum
 	}
-	return body.Sums[int(laddr-btrfsvol.LogicalAddr(item.Key.ObjectID))/csumBlockSize], nil
+	return ret, nil
 }
diff --git a/lib/btrfsprogs/btrfsinspect/scanforextents/scanforextents.go b/lib/btrfsprogs/btrfsinspect/scanforextents/scanforextents.go
index 5e7792e..72c9201 100644
--- a/lib/btrfsprogs/btrfsinspect/scanforextents/scanforextents.go
+++ b/lib/btrfsprogs/btrfsinspect/scanforextents/scanforextents.go
@@ -29,6 +29,7 @@ func ScanForExtents(ctx context.Context, fs *btrfs.FS, blockGroups *BlockGroupTr
 		return nil
 	}
 	runtime.GC()
+	dlog.Info(ctx, "...GC'd")
 
 	devs := fs.LV.PhysicalVolumes()
 	gaps := ListPhysicalGaps(fs)
@@ -122,10 +123,18 @@ func (em *ExtentMappings) init() error {
 func (em *ExtentMappings) logicalSum(laddr btrfsvol.LogicalAddr) (shortSum, error) {
 	entry, ok := em.cacheLogical.Get(laddr)
 	if !ok {
-		sum, err := LookupCSum(em.InFS, em.alg, laddr)
-		entry.Sum = shortSum(sum[:em.alg.Size()])
-		entry.Err = err
-		em.cacheLogical.Add(laddr, entry)
+		sums, err := LookupCSum(em.InFS, em.alg, laddr)
+		if err != nil {
+			entry.Err = err
+			em.cacheLogical.Add(laddr, entry)
+		} else {
+			for laddr, sum := range sums {
+				entry.Sum = shortSum(sum[:em.alg.Size()])
+				em.cacheLogical.Add(laddr, entry)
+			}
+			sum := sums[laddr]
+			entry.Sum = shortSum(sum[:em.alg.Size()])
+		}
 	}
 	return entry.Sum, entry.Err
 }
-- 
cgit v1.2.3-2-g168b