diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c index 1d34560d8c1e..06e292f0b0ae 100644 --- a/drivers/block/nbd.c +++ b/drivers/block/nbd.c @@ -700,38 +700,45 @@ out: return 0; } -/* NULL returned = something went wrong, inform userspace */ -static struct nbd_cmd *nbd_read_stat(struct nbd_device *nbd, int index) +static int nbd_read_reply(struct nbd_device *nbd, int index, + struct nbd_reply *reply) +{ + struct kvec iov = {.iov_base = reply, .iov_len = sizeof(*reply)}; + struct iov_iter to; + int result; + + reply->magic = 0; + iov_iter_kvec(&to, READ, &iov, 1, sizeof(*reply)); + result = sock_xmit(nbd, index, 0, &to, MSG_WAITALL, NULL); + if (result < 0) { + if (!nbd_disconnected(nbd->config)) + dev_err(disk_to_dev(nbd->disk), + "Receive control failed (result %d)\n", result); + return result; + } + + if (ntohl(reply->magic) != NBD_REPLY_MAGIC) { + dev_err(disk_to_dev(nbd->disk), "Wrong magic (0x%lx)\n", + (unsigned long)ntohl(reply->magic)); + return -EPROTO; + } + + return 0; +} + +/* NULL returned = something went wrong, inform userspace */ +static struct nbd_cmd *nbd_handle_reply(struct nbd_device *nbd, int index, + struct nbd_reply *reply) { - struct nbd_config *config = nbd->config; int result; - struct nbd_reply reply; struct nbd_cmd *cmd; struct request *req = NULL; u64 handle; u16 hwq; u32 tag; - struct kvec iov = {.iov_base = &reply, .iov_len = sizeof(reply)}; - struct iov_iter to; int ret = 0; - reply.magic = 0; - iov_iter_kvec(&to, READ, &iov, 1, sizeof(reply)); - result = sock_xmit(nbd, index, 0, &to, MSG_WAITALL, NULL); - if (result < 0) { - if (!nbd_disconnected(config)) - dev_err(disk_to_dev(nbd->disk), - "Receive control failed (result %d)\n", result); - return ERR_PTR(result); - } - - if (ntohl(reply.magic) != NBD_REPLY_MAGIC) { - dev_err(disk_to_dev(nbd->disk), "Wrong magic (0x%lx)\n", - (unsigned long)ntohl(reply.magic)); - return ERR_PTR(-EPROTO); - } - - memcpy(&handle, reply.handle, sizeof(handle)); + memcpy(&handle, reply->handle, sizeof(handle)); tag = nbd_handle_to_tag(handle); hwq = blk_mq_unique_tag_to_hwq(tag); if (hwq < nbd->tag_set.nr_hw_queues) @@ -774,9 +781,9 @@ static struct nbd_cmd *nbd_read_stat(struct nbd_device *nbd, int index) ret = -ENOENT; goto out; } - if (ntohl(reply.error)) { + if (ntohl(reply->error)) { dev_err(disk_to_dev(nbd->disk), "Other side returned error (%d)\n", - ntohl(reply.error)); + ntohl(reply->error)); cmd->status = BLK_STS_IOERR; goto out; } @@ -785,6 +792,7 @@ static struct nbd_cmd *nbd_read_stat(struct nbd_device *nbd, int index) if (rq_data_dir(req) != WRITE) { struct req_iterator iter; struct bio_vec bvec; + struct iov_iter to; rq_for_each_segment(bvec, req, iter) { iov_iter_bvec(&to, READ, &bvec, 1, bvec.bv_len); @@ -798,7 +806,7 @@ static struct nbd_cmd *nbd_read_stat(struct nbd_device *nbd, int index) * and let the timeout stuff handle resubmitting * this request onto another connection. */ - if (nbd_disconnected(config)) { + if (nbd_disconnected(nbd->config)) { cmd->status = BLK_STS_IOERR; goto out; } @@ -822,24 +830,30 @@ static void recv_work(struct work_struct *work) work); struct nbd_device *nbd = args->nbd; struct nbd_config *config = nbd->config; + struct nbd_sock *nsock; struct nbd_cmd *cmd; struct request *rq; while (1) { - cmd = nbd_read_stat(nbd, args->index); - if (IS_ERR(cmd)) { - struct nbd_sock *nsock = config->socks[args->index]; + struct nbd_reply reply; - mutex_lock(&nsock->tx_lock); - nbd_mark_nsock_dead(nbd, nsock, 1); - mutex_unlock(&nsock->tx_lock); + if (nbd_read_reply(nbd, args->index, &reply)) + break; + + cmd = nbd_handle_reply(nbd, args->index, &reply); + if (IS_ERR(cmd)) break; - } rq = blk_mq_rq_from_pdu(cmd); if (likely(!blk_should_fake_timeout(rq->q))) blk_mq_complete_request(rq); } + + nsock = config->socks[args->index]; + mutex_lock(&nsock->tx_lock); + nbd_mark_nsock_dead(nbd, nsock, 1); + mutex_unlock(&nsock->tx_lock); + nbd_config_put(nbd); atomic_dec(&config->recv_threads); wake_up(&config->recv_wq);