diff options
Diffstat (limited to 'lib/btrfsprogs/btrfsinspect/rebuildmappings/rebuildmappings.go')
| -rw-r--r-- | lib/btrfsprogs/btrfsinspect/rebuildmappings/rebuildmappings.go | 222 |
1 files changed, 0 insertions, 222 deletions
diff --git a/lib/btrfsprogs/btrfsinspect/rebuildmappings/rebuildmappings.go b/lib/btrfsprogs/btrfsinspect/rebuildmappings/rebuildmappings.go deleted file mode 100644 index cdf5e5a..0000000 --- a/lib/btrfsprogs/btrfsinspect/rebuildmappings/rebuildmappings.go +++ /dev/null @@ -1,222 +0,0 @@ -// Copyright (C) 2022-2023 Luke Shumaker <lukeshu@lukeshu.com> -// -// SPDX-License-Identifier: GPL-2.0-or-later - -package rebuildmappings - -import ( - "context" - "fmt" - - "github.com/datawire/dlib/dlog" - - "git.lukeshu.com/btrfs-progs-ng/lib/btrfs" - "git.lukeshu.com/btrfs-progs-ng/lib/btrfs/btrfsvol" - "git.lukeshu.com/btrfs-progs-ng/lib/btrfsprogs/btrfsinspect" - "git.lukeshu.com/btrfs-progs-ng/lib/containers" - "git.lukeshu.com/btrfs-progs-ng/lib/maps" - "git.lukeshu.com/btrfs-progs-ng/lib/textui" -) - -func getNodeSize(fs *btrfs.FS) (btrfsvol.AddrDelta, error) { - sb, err := fs.Superblock() - if err != nil { - return 0, err - } - return btrfsvol.AddrDelta(sb.NodeSize), nil -} - -func RebuildMappings(ctx context.Context, fs *btrfs.FS, scanResults btrfsinspect.ScanDevicesResult) error { - nodeSize, err := getNodeSize(fs) - if err != nil { - return err - } - - var numChunks, numDevExts, numBlockGroups, numNodes int - devIDs := maps.SortedKeys(scanResults) - devices := fs.LV.PhysicalVolumes() - for _, devID := range devIDs { - if _, ok := devices[devID]; !ok { - return fmt.Errorf("device ID %v mentioned in scan results is not part of the filesystem", devID) - } - devResults := scanResults[devID] - numChunks += len(devResults.FoundChunks) - numDevExts += len(devResults.FoundDevExtents) - numBlockGroups += len(devResults.FoundBlockGroups) - for _, paddrs := range devResults.FoundNodes { - numNodes += len(paddrs) - } - } - dlog.Infof(ctx, "plan: 1/6 process %d chunks", numChunks) - dlog.Infof(ctx, "plan: 2/6 process %d device extents", numDevExts) - dlog.Infof(ctx, "plan: 3/6 process %d nodes", numNodes) - dlog.Infof(ctx, "plan: 4/6 process %d block groups", numBlockGroups) - dlog.Infof(ctx, "plan: 5/6 search for block groups in checksum map (exact)") - dlog.Infof(ctx, "plan: 6/6 search for block groups in checksum map (fuzzy)") - - _ctx := ctx - ctx = dlog.WithField(_ctx, "btrfsinspect.rebuild-mappings.step", "1/6") - dlog.Infof(_ctx, "1/6: Processing %d chunks...", numChunks) - for _, devID := range devIDs { - devResults := scanResults[devID] - for _, chunk := range devResults.FoundChunks { - for _, mapping := range chunk.Chunk.Mappings(chunk.Key) { - if err := fs.LV.AddMapping(mapping); err != nil { - dlog.Errorf(ctx, "error: adding chunk: %v", err) - } - } - } - } - dlog.Info(_ctx, "... done processing chunks") - - ctx = dlog.WithField(_ctx, "btrfsinspect.rebuild-mappings.step", "2/6") - dlog.Infof(_ctx, "2/6: Processing %d device extents...", numDevExts) - for _, devID := range devIDs { - devResults := scanResults[devID] - for _, ext := range devResults.FoundDevExtents { - if err := fs.LV.AddMapping(ext.DevExt.Mapping(ext.Key)); err != nil { - dlog.Errorf(ctx, "error: adding devext: %v", err) - } - } - } - dlog.Info(_ctx, "... done processing device extents") - - // Do the nodes "last" to avoid bloating the mappings table - // too much. (Because nodes are numerous and small, while the - // others are few and large; so it is likely that many of the - // nodes will be subsumed by other things.) - ctx = dlog.WithField(_ctx, "btrfsinspect.rebuild-mappings.step", "3/6") - dlog.Infof(_ctx, "3/6: Processing %d nodes...", numNodes) - for _, devID := range devIDs { - devResults := scanResults[devID] - // Sort them so that progress numbers are predictable. - for _, laddr := range maps.SortedKeys(devResults.FoundNodes) { - for _, paddr := range devResults.FoundNodes[laddr] { - if err := fs.LV.AddMapping(btrfsvol.Mapping{ - LAddr: laddr, - PAddr: btrfsvol.QualifiedPhysicalAddr{ - Dev: devID, - Addr: paddr, - }, - Size: nodeSize, - SizeLocked: false, - }); err != nil { - dlog.Errorf(ctx, "error: adding node ident: %v", err) - } - } - } - } - dlog.Info(_ctx, "... done processing nodes") - - // Use block groups to add missing flags (and as a hint to - // combine node entries). - ctx = dlog.WithField(_ctx, "btrfsinspect.rebuild-mappings.step", "4/6") - dlog.Infof(_ctx, "4/6: Processing %d block groups...", numBlockGroups) - // First dedup them, because they change for allocations and - // CoW means that they'll bounce around a lot, so you likely - // have oodles of duplicates? - bgs, err := DedupBlockGroups(scanResults) - if err != nil { - return err - } - dlog.Infof(ctx, "... de-duplicated to %d block groups", len(bgs)) - for _, bgLAddr := range maps.SortedKeys(bgs) { - bg := bgs[bgLAddr] - otherLAddr, otherPAddr := fs.LV.ResolveAny(bg.LAddr, bg.Size) - if otherLAddr < 0 || otherPAddr.Addr < 0 { - dlog.Errorf(ctx, "error: could not pair blockgroup laddr=%v (size=%v flags=%v) with a mapping", - bg.LAddr, bg.Size, bg.Flags) - continue - } - - offsetWithinChunk := otherLAddr.Sub(bg.LAddr) - mapping := btrfsvol.Mapping{ - LAddr: bg.LAddr, - PAddr: otherPAddr.Add(-offsetWithinChunk), - Size: bg.Size, - SizeLocked: true, - Flags: containers.Optional[btrfsvol.BlockGroupFlags]{ - OK: true, - Val: bg.Flags, - }, - } - if err := fs.LV.AddMapping(mapping); err != nil { - dlog.Errorf(ctx, "error: adding flags from blockgroup: %v", err) - continue - } - delete(bgs, bgLAddr) - } - dlog.Info(_ctx, "... done processing block groups") - - // More than once, I've been tempted to get rid of this exact-search step and just have the fuzzy-search step. - // After all, looking at the timestamps in the log, it's faster per blockgroup! For some background, the big-O - // for each (per blockgroup) looks like: - // - // - exact-search: O(bgSize+physicalBlocks) - // - fuzzy-search: O(bgSize*physicalBlocks) worst-case; O(bgSize*log(physicalBlocks)) expected - // - // The fuzzy-search is only fast because the exact-search is so good at getting `physicalBlocks` down. - // Empirically: if I remove the exact-search step, then the fuzzy-match step is more than an order of magnitude - // slower. - ctx = dlog.WithField(_ctx, "btrfsinspect.rebuild-mappings.step", "5/6") - dlog.Infof(_ctx, "5/6: Searching for %d block groups in checksum map (exact)...", len(bgs)) - physicalSums := ExtractPhysicalSums(scanResults) - logicalSums := ExtractLogicalSums(ctx, scanResults) - if err := matchBlockGroupSums(ctx, fs, bgs, physicalSums, logicalSums); err != nil { - return err - } - dlog.Info(ctx, "... done searching for exact block groups") - - ctx = dlog.WithField(_ctx, "btrfsinspect.rebuild-mappings.step", "6/6") - dlog.Infof(_ctx, "6/6: Searching for %d block groups in checksum map (fuzzy)...", len(bgs)) - if err := fuzzyMatchBlockGroupSums(ctx, fs, bgs, physicalSums, logicalSums); err != nil { - return err - } - dlog.Info(_ctx, "... done searching for fuzzy block groups") - - ctx = dlog.WithField(_ctx, "btrfsinspect.rebuild-mappings.step", "report") - dlog.Info(_ctx, "report:") - - unmappedPhysicalRegions := ListUnmappedPhysicalRegions(fs) - var unmappedPhysical btrfsvol.AddrDelta - var numUnmappedPhysical int - for _, devRegions := range unmappedPhysicalRegions { - numUnmappedPhysical += len(devRegions) - for _, region := range devRegions { - unmappedPhysical += region.End.Sub(region.Beg) - } - } - dlog.Infof(ctx, "... %d of unmapped physical space (across %d regions)", textui.IEC(unmappedPhysical, "B"), numUnmappedPhysical) - - unmappedLogicalRegions := ListUnmappedLogicalRegions(fs, logicalSums) - var unmappedLogical btrfsvol.AddrDelta - for _, region := range unmappedLogicalRegions { - unmappedLogical += region.Size() - } - dlog.Infof(ctx, "... %d of unmapped summed logical space (across %d regions)", textui.IEC(unmappedLogical, "B"), len(unmappedLogicalRegions)) - - var unmappedBlockGroups btrfsvol.AddrDelta - for _, bg := range bgs { - unmappedBlockGroups += bg.Size - } - dlog.Infof(ctx, "... %d of unmapped block groups (across %d groups)", textui.IEC(unmappedBlockGroups, "B"), len(bgs)) - - dlog.Info(_ctx, "detailed report:") - for _, devID := range maps.SortedKeys(unmappedPhysicalRegions) { - for _, region := range unmappedPhysicalRegions[devID] { - dlog.Infof(ctx, "... unmapped physical region: dev=%v beg=%v end=%v (size=%v)", - devID, region.Beg, region.End, region.End.Sub(region.Beg)) - } - } - for _, region := range unmappedLogicalRegions { - dlog.Infof(ctx, "... umapped summed logical region: beg=%v end=%v (size=%v)", - region.Addr, region.Addr.Add(region.Size()), region.Size()) - } - for _, laddr := range maps.SortedKeys(bgs) { - bg := bgs[laddr] - dlog.Infof(ctx, "... umapped block group: beg=%v end=%v (size=%v) flags=%v", - bg.LAddr, bg.LAddr.Add(bg.Size), bg.Size, bg.Flags) - } - - return nil -} |