From 09035f86496d8dea7a05a07f6dcb8083c0a3d885 Mon Sep 17 00:00:00 2001 From: Daniel Wagner Date: Mon, 29 Aug 2022 11:28:40 +0200 Subject: [PATCH] nvme-tcp: handle number of queue changes On reconnect, the number of queues might have changed. In the case where we have more queues available than previously we try to access queues which are not initialized yet. The other case where we have less queues than previously, the connection attempt will fail because the target doesn't support the old number of queues and we end up in a reconnect loop. Thus, only start queues which are currently present in the tagset limited by the number of available queues. Then we update the tagset and we can start any new queue. Signed-off-by: Daniel Wagner Reviewed-by: Sagi Grimberg Reviewed-by: Hannes Reinecke Signed-off-by: Christoph Hellwig --- drivers/nvme/host/tcp.c | 26 +++++++++++++++++++++----- 1 file changed, 21 insertions(+), 5 deletions(-) diff --git a/drivers/nvme/host/tcp.c b/drivers/nvme/host/tcp.c index ef151c23d495..4c2d198145a7 100644 --- a/drivers/nvme/host/tcp.c +++ b/drivers/nvme/host/tcp.c @@ -1762,11 +1762,12 @@ static void nvme_tcp_stop_io_queues(struct nvme_ctrl *ctrl) nvme_tcp_stop_queue(ctrl, i); } -static int nvme_tcp_start_io_queues(struct nvme_ctrl *ctrl) +static int nvme_tcp_start_io_queues(struct nvme_ctrl *ctrl, + int first, int last) { int i, ret; - for (i = 1; i < ctrl->queue_count; i++) { + for (i = first; i < last; i++) { ret = nvme_tcp_start_queue(ctrl, i); if (ret) goto out_stop_queues; @@ -1775,7 +1776,7 @@ static int nvme_tcp_start_io_queues(struct nvme_ctrl *ctrl) return 0; out_stop_queues: - for (i--; i >= 1; i--) + for (i--; i >= first; i--) nvme_tcp_stop_queue(ctrl, i); return ret; } @@ -1901,7 +1902,7 @@ static void nvme_tcp_destroy_io_queues(struct nvme_ctrl *ctrl, bool remove) static int nvme_tcp_configure_io_queues(struct nvme_ctrl *ctrl, bool new) { - int ret; + int ret, nr_queues; ret = nvme_tcp_alloc_io_queues(ctrl); if (ret) @@ -1917,7 +1918,13 @@ static int nvme_tcp_configure_io_queues(struct nvme_ctrl *ctrl, bool new) goto out_free_tag_set; } - ret = nvme_tcp_start_io_queues(ctrl); + /* + * Only start IO queues for which we have allocated the tagset + * and limitted it to the available queues. On reconnects, the + * queue number might have changed. + */ + nr_queues = min(ctrl->tagset->nr_hw_queues + 1, ctrl->queue_count); + ret = nvme_tcp_start_io_queues(ctrl, 1, nr_queues); if (ret) goto out_cleanup_connect_q; @@ -1937,6 +1944,15 @@ static int nvme_tcp_configure_io_queues(struct nvme_ctrl *ctrl, bool new) nvme_unfreeze(ctrl); } + /* + * If the number of queues has increased (reconnect case) + * start all new queues now. + */ + ret = nvme_tcp_start_io_queues(ctrl, nr_queues, + ctrl->tagset->nr_hw_queues + 1); + if (ret) + goto out_wait_freeze_timed_out; + return 0; out_wait_freeze_timed_out: