diff options
Diffstat (limited to 'drivers/block/drbd/drbd_req.c')
-rw-r--r-- | drivers/block/drbd/drbd_req.c | 120 |
1 files changed, 84 insertions, 36 deletions
diff --git a/drivers/block/drbd/drbd_req.c b/drivers/block/drbd/drbd_req.c index 2255dcf..66b8e4b 100644 --- a/drivers/block/drbd/drbd_req.c +++ b/drivers/block/drbd/drbd_req.c @@ -47,8 +47,7 @@ static void _drbd_end_io_acct(struct drbd_device *device, struct drbd_request *r &device->vdisk->part0, req->start_jif); } -static struct drbd_request *drbd_req_new(struct drbd_device *device, - struct bio *bio_src) +static struct drbd_request *drbd_req_new(struct drbd_device *device, struct bio *bio_src) { struct drbd_request *req; @@ -58,10 +57,12 @@ static struct drbd_request *drbd_req_new(struct drbd_device *device, memset(req, 0, sizeof(*req)); drbd_req_make_private_bio(req, bio_src); - req->rq_state = bio_data_dir(bio_src) == WRITE ? RQ_WRITE : 0; - req->device = device; - req->master_bio = bio_src; - req->epoch = 0; + req->rq_state = (bio_data_dir(bio_src) == WRITE ? RQ_WRITE : 0) + | (bio_op(bio_src) == REQ_OP_WRITE_SAME ? RQ_WSAME : 0) + | (bio_op(bio_src) == REQ_OP_DISCARD ? RQ_UNMAP : 0); + req->device = device; + req->master_bio = bio_src; + req->epoch = 0; drbd_clear_interval(&req->i); req->i.sector = bio_src->bi_iter.bi_sector; @@ -218,7 +219,6 @@ void drbd_req_complete(struct drbd_request *req, struct bio_and_error *m) { const unsigned s = req->rq_state; struct drbd_device *device = req->device; - int rw; int error, ok; /* we must not complete the master bio, while it is @@ -242,8 +242,6 @@ void drbd_req_complete(struct drbd_request *req, struct bio_and_error *m) return; } - rw = bio_rw(req->master_bio); - /* * figure out whether to report success or failure. * @@ -267,7 +265,7 @@ void drbd_req_complete(struct drbd_request *req, struct bio_and_error *m) * epoch number. If they match, increase the current_tle_nr, * and reset the transfer log epoch write_cnt. */ - if (rw == WRITE && + if (op_is_write(bio_op(req->master_bio)) && req->epoch == atomic_read(&first_peer_device(device)->connection->current_tle_nr)) start_new_tl_epoch(first_peer_device(device)->connection); @@ -284,11 +282,14 @@ void drbd_req_complete(struct drbd_request *req, struct bio_and_error *m) * because no path was available, in which case * it was not even added to the transfer_log. * - * READA may fail, and will not be retried. + * read-ahead may fail, and will not be retried. * * WRITE should have used all available paths already. */ - if (!ok && rw == READ && !list_empty(&req->tl_requests)) + if (!ok && + bio_op(req->master_bio) == REQ_OP_READ && + !(req->master_bio->bi_rw & REQ_RAHEAD) && + !list_empty(&req->tl_requests)) req->rq_state |= RQ_POSTPONED; if (!(req->rq_state & RQ_POSTPONED)) { @@ -644,7 +645,7 @@ int __req_mod(struct drbd_request *req, enum drbd_req_event what, __drbd_chk_io_error(device, DRBD_READ_ERROR); /* fall through. */ case READ_AHEAD_COMPLETED_WITH_ERROR: - /* it is legal to fail READA, no __drbd_chk_io_error in that case. */ + /* it is legal to fail read-ahead, no __drbd_chk_io_error in that case. */ mod_rq_state(req, m, RQ_LOCAL_PENDING, RQ_LOCAL_COMPLETED); break; @@ -656,7 +657,7 @@ int __req_mod(struct drbd_request *req, enum drbd_req_event what, break; case QUEUE_FOR_NET_READ: - /* READ or READA, and + /* READ, and * no local disk, * or target area marked as invalid, * or just got an io-error. */ @@ -977,16 +978,20 @@ static void complete_conflicting_writes(struct drbd_request *req) sector_t sector = req->i.sector; int size = req->i.size; - i = drbd_find_overlap(&device->write_requests, sector, size); - if (!i) - return; - for (;;) { - prepare_to_wait(&device->misc_wait, &wait, TASK_UNINTERRUPTIBLE); - i = drbd_find_overlap(&device->write_requests, sector, size); - if (!i) + drbd_for_each_overlap(i, &device->write_requests, sector, size) { + /* Ignore, if already completed to upper layers. */ + if (i->completed) + continue; + /* Handle the first found overlap. After the schedule + * we have to restart the tree walk. */ + break; + } + if (!i) /* if any */ break; + /* Indicate to wake up device->misc_wait on progress. */ + prepare_to_wait(&device->misc_wait, &wait, TASK_UNINTERRUPTIBLE); i->waiting = true; spin_unlock_irq(&device->resource->req_lock); schedule(); @@ -995,7 +1000,7 @@ static void complete_conflicting_writes(struct drbd_request *req) finish_wait(&device->misc_wait, &wait); } -/* called within req_lock and rcu_read_lock() */ +/* called within req_lock */ static void maybe_pull_ahead(struct drbd_device *device) { struct drbd_connection *connection = first_peer_device(device)->connection; @@ -1132,7 +1137,7 @@ static int drbd_process_write_request(struct drbd_request *req) * replicating, in which case there is no point. */ if (unlikely(req->i.size == 0)) { /* The only size==0 bios we expect are empty flushes. */ - D_ASSERT(device, req->master_bio->bi_rw & REQ_FLUSH); + D_ASSERT(device, req->master_bio->bi_rw & REQ_PREFLUSH); if (remote) _req_mod(req, QUEUE_AS_DRBD_BARRIER); return remote; @@ -1152,12 +1157,29 @@ static int drbd_process_write_request(struct drbd_request *req) return remote; } +static void drbd_process_discard_req(struct drbd_request *req) +{ + int err = drbd_issue_discard_or_zero_out(req->device, + req->i.sector, req->i.size >> 9, true); + + if (err) + req->private_bio->bi_error = -EIO; + bio_endio(req->private_bio); +} + static void drbd_submit_req_private_bio(struct drbd_request *req) { struct drbd_device *device = req->device; struct bio *bio = req->private_bio; - const int rw = bio_rw(bio); + unsigned int type; + + if (bio_op(bio) != REQ_OP_READ) + type = DRBD_FAULT_DT_WR; + else if (bio->bi_rw & REQ_RAHEAD) + type = DRBD_FAULT_DT_RA; + else + type = DRBD_FAULT_DT_RD; bio->bi_bdev = device->ldev->backing_bdev; @@ -1167,11 +1189,10 @@ drbd_submit_req_private_bio(struct drbd_request *req) * stable storage, and this is a WRITE, we may not even submit * this bio. */ if (get_ldev(device)) { - if (drbd_insert_fault(device, - rw == WRITE ? DRBD_FAULT_DT_WR - : rw == READ ? DRBD_FAULT_DT_RD - : DRBD_FAULT_DT_RA)) + if (drbd_insert_fault(device, type)) bio_io_error(bio); + else if (bio_op(bio) == REQ_OP_DISCARD) + drbd_process_discard_req(req); else generic_make_request(bio); put_ldev(device); @@ -1223,24 +1244,45 @@ drbd_request_prepare(struct drbd_device *device, struct bio *bio, unsigned long /* Update disk stats */ _drbd_start_io_acct(device, req); + /* process discards always from our submitter thread */ + if (bio_op(bio) & REQ_OP_DISCARD) + goto queue_for_submitter_thread; + if (rw == WRITE && req->private_bio && req->i.size && !test_bit(AL_SUSPENDED, &device->flags)) { - if (!drbd_al_begin_io_fastpath(device, &req->i)) { - atomic_inc(&device->ap_actlog_cnt); - drbd_queue_write(device, req); - return NULL; - } + if (!drbd_al_begin_io_fastpath(device, &req->i)) + goto queue_for_submitter_thread; req->rq_state |= RQ_IN_ACT_LOG; req->in_actlog_jif = jiffies; } - return req; + + queue_for_submitter_thread: + atomic_inc(&device->ap_actlog_cnt); + drbd_queue_write(device, req); + return NULL; +} + +/* Require at least one path to current data. + * We don't want to allow writes on C_STANDALONE D_INCONSISTENT: + * We would not allow to read what was written, + * we would not have bumped the data generation uuids, + * we would cause data divergence for all the wrong reasons. + * + * If we don't see at least one D_UP_TO_DATE, we will fail this request, + * which either returns EIO, or, if OND_SUSPEND_IO is set, suspends IO, + * and queues for retry later. + */ +static bool may_do_writes(struct drbd_device *device) +{ + const union drbd_dev_state s = device->state; + return s.disk == D_UP_TO_DATE || s.pdsk == D_UP_TO_DATE; } static void drbd_send_and_submit(struct drbd_device *device, struct drbd_request *req) { struct drbd_resource *resource = device->resource; - const int rw = bio_rw(req->master_bio); + const int rw = bio_data_dir(req->master_bio); struct bio_and_error m = { NULL, }; bool no_remote = false; bool submit_private_bio = false; @@ -1270,7 +1312,7 @@ static void drbd_send_and_submit(struct drbd_device *device, struct drbd_request goto out; } - /* We fail READ/READA early, if we can not serve it. + /* We fail READ early, if we can not serve it. * We must do this before req is registered on any lists. * Otherwise, drbd_req_complete() will queue failed READ for retry. */ if (rw != WRITE) { @@ -1291,6 +1333,12 @@ static void drbd_send_and_submit(struct drbd_device *device, struct drbd_request } if (rw == WRITE) { + if (req->private_bio && !may_do_writes(device)) { + bio_put(req->private_bio); + req->private_bio = NULL; + put_ldev(device); + goto nodata; + } if (!drbd_process_write_request(req)) no_remote = true; } else { |