On Tue, Feb 27, 2024 at 02:37:28PM +1300, Michael Schmitz wrote: > [ commit d28e4dff085c5a87025c9a0a85fb798bd8e9ca17 upstream ] > > As it turns out, my earlier patch in commit 86d46fdaa12a (block: > ataflop: fix breakage introduced at blk-mq refactoring) was > incomplete. This patch fixes any remaining issues found during > more testing and code review. > > Requests exceeding 4 k are handled in 4k segments but > __blk_mq_end_request() is never called on these (still > sectors outstanding on the request). With redo_fd_request() > removed, there is no provision to kick off processing of the > next segment, causing requests exceeding 4k to hang. (By > setting /sys/block/fd0/queue/max_sectors_k <= 4 as workaround, > this behaviour can be avoided). > > Instead of reintroducing redo_fd_request(), requeue the remainder > of the request by calling blk_mq_requeue_request() on incomplete > requests (i.e. when blk_update_request() still returns true), and > rely on the block layer to queue the residual as new request. > > Both error handling and formatting needs to release the > ST-DMA lock, so call finish_fdc() on these (this was previously > handled by redo_fd_request()). finish_fdc() may be called > legitimately without the ST-DMA lock held - make sure we only > release the lock if we actually held it. In a similar way, > early exit due to errors in ataflop_queue_rq() must release > the lock. > > After minor errors, fd_error sets up to recalibrate the drive > but never re-runs the current operation (another task handled by > redo_fd_request() before). Call do_fd_action() to get the next > steps (seek, retry read/write) underway. > > Signed-off-by: Michael Schmitz <schmitzmic@xxxxxxxxx> > Fixes: 6ec3938cff95f (ataflop: convert to blk-mq) > Fixes: 86d46fdaa12a (block: ataflop: fix breakage introduced at blk-mq refactoring) > CC: stable@xxxxxxxxxxxxxxx # 5.10.x > Link: https://lore.kernel.org/r/20211024002013.9332-1-schmitzmic@xxxxxxxxx > Signed-off-by: Jens Axboe <axboe@xxxxxxxxx> > [MSch: v5.10 backport merge conflict fix] Now queued up, thanks. greg k-h
