Fix 1: delete stall guard from Disc::copy. Pass 1 must sweep end-to-end
per ddrescue model (RIP_DESIGN.md §2.1, §3, §9). The v0.13.9 guard at
disc/mod.rs broke Pass 1 at 30% on Dune 2 with 56 GB still NonTried.
Removed stall_secs field, narrative comment in scsi/linux.rs, and the
broken regression test. Replaced with test_disc_copy_completes_full_disc_
with_failing_reader and test_disc_copy_halts_promptly_on_failing_reader.
Fix 2: async SCSI transport recovery. Added Arc<AtomicI32> fd_recovery
on SgIoTransport. On poll timeout: spawn close + spawn open in
background, return Err immediately. Top of execute() swaps fd from
recovery atomic. Main thread never blocked beyond ~1.5s poll budget
(was up to ~60s per timeout because kernel serialized main-thread
open() against in-flight close()). Drop drains pending recovery fd.
§15.1 cross-platform parity: Windows + macOS now have the same
observable recovery contract. SptiTransport gets try_recover()
(synchronous CloseHandle + CreateFileW; Windows close is fast, no
in-flight CDB drain like Linux). MacScsiTransport gets try_recover()
(release IOKit interface + reacquire via new acquire_device_iface()
helper); stores bsd_name for re-resolution. Drop guards null'd-out
interfaces. Stripped English error strings ("try as root" / "run as
administrator") on Linux + Windows. Fixed Windows TimeOutValue
ms→s ceiling so 1500ms gets 2s (was 1s; broke Drive::read fast path).
Fix 4: instrument Disc::patch arms. PatchResult exposes
blocks_attempted, blocks_read_ok, blocks_read_failed so the v0.13.11
mystery (Dune 2 Pass 2 recovered 0 bytes in 100 min) is diagnosable
from the live device log without re-instrumenting from outside.
Cleanup: honor PatchOptions::full_recovery (was read into _ and
ignored; now routed to read_sectors recovery arg). Updated
CopyOptions::batch_sectors doc to describe the actual production
path (sysfs detect_max_batch_sectors, typically 60 sectors / ~120 KB
on BU40N) rather than the test-only 32-sector internal default.
All four crates clippy-clean and tests green on the host targets
(macOS native + cargo check on Linux). Cross-platform CI watches
Linux + Windows + macOS builds + tests.
Fixes the silent Pass 1 hang observed on Dune 2 with v0.13.8 (drive
grinding through bad sectors at 0 KB/s, errs=0, no error surfaced).
Root cause: SgIoTransport::execute's reopen-after-poll-timeout opened
a fresh /dev/sg* fd on the main thread, which serialized against the
spawned close() of the old fd via the kernel's per-device state lock.
The userspace 1.5s timeout still fired, but the abandon-and-reopen
recovery itself blocked the main thread for as long as close() took.
Net: reads returned slowly, skip-forward fired on every iteration,
bytes_good never advanced.
- SgIoTransport::execute: on poll timeout, spawn close, set fd=-1,
return Err. No reopen on the main thread. The transport is now
invalidated until the consumer creates a fresh Drive.
- Disc::copy: add stall guard. CopyOptions.stall_secs (default 120s).
If bytes_good doesn't advance for the threshold, break 'outer
cleanly with complete=false, bytes_pending > 0 so Pass 2 retries
pick up the NonTrimmed ranges with recovery=true 30s timeouts.
- New regression test: test_disc_copy_stall_detection_triggers_
skip_forward in tests/integration_progress_and_halt.rs.
Updates docs/ to reflect the recovery-loop strip:
- rip-recovery.md: drops Phase 1/2/3 description, replaces with three-layer
model (Disc::patch multi-pass / DiscStream batch halving / Drive::read
single-shot). Notes that no SCSI resets fire from any retry path.
- drive-access.md: removes SG_SCSI_RESET + STOP/START UNIT escalation
references; SgIoTransport::reset is now kernel SG_IO flush + ALLOW
MEDIUM REMOVAL only.
- src/mux/disc.rs + tests/: cargo fmt cleanup.
Drive::read is now single-shot. Phase 1/2/3 retries + scsi::reset+reopen
removed (~80 lines). recovery=true bumps timeout to 30s; recovery=false
stays at 1.5s. On any failure returns Err(DiscRead) immediately — caller
(Disc::patch outer loop, DiscStream batch halver) handles retries.
Inline reset+reopen WAS the wedge primitive on the LG BU40N. Per prior
post-mortem, every USB/SCSI reset path tested fails to recover the
wedged Initio bridge — the inline retry was pure cost.
SgIoTransport::reset (Linux) trimmed to kernel SG_IO state flush +
ALLOW MEDIUM REMOVAL. SG_SCSI_RESET ioctl + STOP/START UNIT escalation
removed. macOS reset removed (no-op). scsi::reset() top-level family
removed (no callers).
EventKind::BytesRead { bytes, total } now actually emitted from
DiscStream::fill_extents after each successful sector read. Was
declared in 0.13.0, never fired. Drives autorip per-device progress
in direct mode.
EventKind::Retry / SectorRecovered no longer emitted (variants kept
for forward compat). SpeedChange still emitted via Drive::set_speed
public path.
Tests: new tests/integration_progress_and_halt.rs (5 tests). 233 unit
tests + 5 integration green.
MattJackson