From: Lars Ellenberg Date: Tue, 29 Aug 2017 08:20:35 +0000 (+0200) Subject: drbd: Send P_NEG_ACK upon write error in protocol != C X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=e1fbc4ca9d0353a932994cb1ac38e87e5a211a9f;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git drbd: Send P_NEG_ACK upon write error in protocol != C In protocol != C, we forgot to send the P_NEG_ACK for failing writes. Once we no longer submit to local disk, because we already "detached", due to the typical "on-io-error detach;" config setting, we already send the neg acks right away. Only those requests that have been submitted, and have been error-completed by the local disk, would forget to send the neg-ack, and only in asynchronous replication (protocol != C). Unless this happened during resync, where we already always send acks, regardless of protocol. The primary side needs the P_NEG_ACK in order to mark the affected block(s) for resync in its out-of-sync bitmap. If the blocks in question are not re-written again, we may miss to resync them later, causing data inconsistencies. This patch will always send the neg-acks, and also at least try to persist the out-of-sync status on the local node already. Signed-off-by: Philipp Reisner Signed-off-by: Lars Ellenberg Signed-off-by: Jens Axboe --- diff --git a/drivers/block/drbd/drbd_worker.c b/drivers/block/drbd/drbd_worker.c index 2745db2255ed..72cb0bd624a6 100644 --- a/drivers/block/drbd/drbd_worker.c +++ b/drivers/block/drbd/drbd_worker.c @@ -128,6 +128,14 @@ void drbd_endio_write_sec_final(struct drbd_peer_request *peer_req) __releases(l block_id = peer_req->block_id; peer_req->flags &= ~EE_CALL_AL_COMPLETE_IO; + if (peer_req->flags & EE_WAS_ERROR) { + /* In protocol != C, we usually do not send write acks. + * In case of a write error, send the neg ack anyways. */ + if (!__test_and_set_bit(__EE_SEND_WRITE_ACK, &peer_req->flags)) + inc_unacked(device); + drbd_set_out_of_sync(device, peer_req->i.sector, peer_req->i.size); + } + spin_lock_irqsave(&device->resource->req_lock, flags); device->writ_cnt += peer_req->i.size >> 9; list_move_tail(&peer_req->w.list, &device->done_ee);