nvme: set non-mdts limits in nvme_scan_work

In current implementation we set the non-mdts limits by calling
nvme_init_non_mdts_limits() from nvme_init_ctrl_finish().
This also tries to set the limits for the discovery controller which
has no I/O queues resulting in the warning message reported by the
nvme_log_error() when running blktest nvme/002: -

[ 2005.155946] run blktests nvme/002 at 2022-04-09 16:57:47
[ 2005.192223] loop: module loaded
[ 2005.196429] nvmet: adding nsid 1 to subsystem blktests-subsystem-0
[ 2005.200334] nvmet: adding nsid 1 to subsystem blktests-subsystem-1

<------------------------------SNIP---------------------------------->

[ 2008.958108] nvmet: adding nsid 1 to subsystem blktests-subsystem-997
[ 2008.962082] nvmet: adding nsid 1 to subsystem blktests-subsystem-998
[ 2008.966102] nvmet: adding nsid 1 to subsystem blktests-subsystem-999
[ 2008.973132] nvmet: creating discovery controller 1 for subsystem nqn.2014-08.org.nvmexpress.discovery for NQN testhostnqn.
*[ 2008.973196] nvme1: Identify(0x6), Invalid Field in Command (sct 0x0 / sc 0x2) MORE DNR*
[ 2008.974595] nvme nvme1: new ctrl: "nqn.2014-08.org.nvmexpress.discovery"
[ 2009.103248] nvme nvme1: Removing ctrl: NQN "nqn.2014-08.org.nvmexpress.discovery"

Move the call of nvme_init_non_mdts_limits() to nvme_scan_work() after
we verify that I/O queues are created since that is a converging point
for each transport where these limits are actually used.

1. FC :
nvme_fc_create_association()
 ...
 nvme_fc_create_io_queues(ctrl);
 ...
 nvme_start_ctrl()
  nvme_scan_queue()
   nvme_scan_work()

2. PCIe:-
nvme_reset_work()
 ...
 nvme_setup_io_queues()
  nvme_create_io_queues()
   nvme_alloc_queue()
 ...
 nvme_start_ctrl()
  nvme_scan_queue()
   nvme_scan_work()

3. RDMA :-
nvme_rdma_setup_ctrl
 ...
  nvme_rdma_configure_io_queues
  ...
  nvme_start_ctrl()
   nvme_scan_queue()
    nvme_scan_work()

4. TCP :-
nvme_tcp_setup_ctrl
 ...
  nvme_tcp_configure_io_queues
  ...
  nvme_start_ctrl()
   nvme_scan_queue()
    nvme_scan_work()

* nvme_scan_work()
...
nvme_validate_or_alloc_ns()
  nvme_alloc_ns()
   nvme_update_ns_info()
    nvme_update_disk_info()
     nvme_config_discard() <---
     blk_queue_max_write_zeroes_sectors() <---

Signed-off-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>

diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
index faeb032..a7660e4 100644 (file)
--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -3129,10 +3129,6 @@ int nvme_init_ctrl_finish(struct nvme_ctrl *ctrl)
        if (ret)
                return ret;
 
-       ret = nvme_init_non_mdts_limits(ctrl);
-       if (ret < 0)
-               return ret;
-
        ret = nvme_configure_apst(ctrl);
        if (ret < 0)
                return ret;
@@ -4301,11 +4297,26 @@ static void nvme_scan_work(struct work_struct *work)
 {
        struct nvme_ctrl *ctrl =
                container_of(work, struct nvme_ctrl, scan_work);
+       int ret;
 
        /* No tagset on a live ctrl means IO queues could not created */
        if (ctrl->state != NVME_CTRL_LIVE || !ctrl->tagset)
                return;
 
+       /*
+        * Identify controller limits can change at controller reset due to
+        * new firmware download, even though it is not common we cannot ignore
+        * such scenario. Controller's non-mdts limits are reported in the unit
+        * of logical blocks that is dependent on the format of attached
+        * namespace. Hence re-read the limits at the time of ns allocation.
+        */
+       ret = nvme_init_non_mdts_limits(ctrl);
+       if (ret < 0) {
+               dev_warn(ctrl->device,
+                       "reading non-mdts-limits failed: %d\n", ret);
+               return;
+       }
+
        if (test_and_clear_bit(NVME_AER_NOTICE_NS_CHANGED, &ctrl->events)) {
                dev_info(ctrl->device, "rescanning namespaces.\n");
                nvme_clear_changed_ns_log(ctrl);