[PATCH 4.14 17/43] nvmet: dont check iosqes,iocqes for discovery controllers

Greg Kroah-Hartman
2021-03-22T13:15:11Z

From: Sagi Grimberg <sagi@grimberg.me>

commit d218a8a3003e84ab136e69a4e30dd4ec7dab2d22 upstream.

>From the base spec, Figure 78:

"Controller Configuration, these fields are defined as parameters to
configure an "I/O Controller (IOC)" and not to configure a "Discovery
Controller (DC).

...
If the controller does not support I/O queues, then this field shall
be read-only with a value of 0h

Just perform this check for I/O controllers.

Fixes: a07b4970f464 ("nvmet: add a generic NVMe target")
Reported-by: Belanger, Martin <Martin.Belanger@dell.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/nvme/target/core.c | 17 ++++++++++++++---
1 file changed, 14 insertions(+), 3 deletions(-)

--- a/drivers/nvme/target/core.c
+++ b/drivers/nvme/target/core.c
@@ -594,9 +594,20 @@ static void nvmet_start_ctrl(struct nvme
{
lockdep_assert_held(&ctrl->lock);

- if (nvmet_cc_iosqes(ctrl->cc) != NVME_NVM_IOSQES ||
- nvmet_cc_iocqes(ctrl->cc) != NVME_NVM_IOCQES ||
- nvmet_cc_mps(ctrl->cc) != 0 ||
+ /*
+ * Only I/O controllers should verify iosqes,iocqes.
+ * Strictly speaking, the spec says a discovery controller
+ * should verify iosqes,iocqes are zeroed, however that
+ * would break backwards compatibility, so don't enforce it.
+ */
+ if (ctrl->subsys->type != NVME_NQN_DISC &&
+ (nvmet_cc_iosqes(ctrl->cc) != NVME_NVM_IOSQES ||
+ nvmet_cc_iocqes(ctrl->cc) != NVME_NVM_IOCQES)) {
+ ctrl->csts = NVME_CSTS_CFS;
+ return;
+ }
+
+ if (nvmet_cc_mps(ctrl->cc) != 0 ||
nvmet_cc_ams(ctrl->cc) != 0 ||
nvmet_cc_css(ctrl->cc) != 0) {
ctrl->csts = NVME_CSTS_CFS;