linux-stable/drivers/nvme
Evan Burgess 536ecccbaf nvmet: configfs: use ctrl->instance to track passthru subsystems
To prevent enabling more than one passthrough subsystem per NVMe
controller, passthru.c maintains an xarray indexed by cntlid values.
Passthrough for a given nvmet subsystem cannot be enabled by configfs
if the subsystem's passthru_ctrl->cntlid value is already accounted
for in the xarray.

However, according to the NVMe spec (rev 2.0c, p.145), "The Controller
ID (CNTLID) value returned in the Identify Controller data structure
may be used to uniquely identify a controller within an NVM subsystem,"
meaning that cntlid values are not guaranteed to be globally unique
across multiple subsystems. Instead, the cntlid only uniquely
identifies multiple controllers _within_ a subsystem.

As a result, multiple unique & valid NVMe targets can be blocked from
enabling passthrough at the same time if their controllers share cntlid
values, a behavior allowed by the spec. Fix this by indexing the xarray
with passthru_ctrl->instance values, which are allocated per
controller by IDA and thus should be truly unique.

Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Evan Burgess <evan.burgess@seagate.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
2023-12-19 09:10:22 -08:00
..
common nvme: keyring: fix conditional compilation 2023-11-08 08:07:08 -08:00
host nvme: repack struct nvme_ns_head 2023-12-19 09:10:13 -08:00
target nvmet: configfs: use ctrl->instance to track passthru subsystems 2023-12-19 09:10:22 -08:00
Kconfig nvme: implement In-Band authentication 2022-08-02 17:14:49 -06:00
Makefile nvme: common: make keyring and auth separate modules 2023-11-07 10:05:15 -08:00