linux.git/drivers/nvme/target/admin-cmd.c, branch v5.19

nvmet: use a private workqueue instead of the system workqueue

2022-03-29T07:29:04+00:00

Any attempt to flush kernel-global WQs has possibility of deadlock
so we should simply stop using them, instead introduce nvmet_wq
which is the generic nvmet workqueue for work elements that
don't explicitly require a dedicated workqueue (by the mere fact
that they are using the system_wq).

Changes were done using the following replaces:

 - s/schedule_work(/queue_work(nvmet_wq, /g
 - s/schedule_delayed_work(/queue_delayed_work(nvmet_wq, /g
 - s/flush_scheduled_work()/flush_workqueue(nvmet_wq)/g

Reported-by: Tetsuo Handa 
Signed-off-by: Sagi Grimberg 
Reviewed-by: Chaitanya Kulkarni 
Signed-off-by: Christoph Hellwig

nvmet: move the call to nvmet_ns_changed out of nvmet_ns_revalidate

2022-03-15T09:36:47+00:00

nvmet_ns_changed states via lockdep that the ns->subsys->lock must be
held. The only caller of nvmet_ns_changed which does not acquire that
lock is nvmet_ns_revalidate. nvmet_ns_revalidate has 3 callers,
of which 2 do not acquire that lock: nvmet_execute_identify_cns_cs_ns
and nvmet_execute_identify_ns. The other caller
nvmet_ns_revalidate_size_store does acquire the lock.

Move the call to nvmet_ns_changed from nvmet_ns_revalidate to the callers
so that they can perform the correct locking as needed.

This issue was found using a static type-based analyser and manually
verified.

Reported-by: Niels Dossche 
Signed-off-by: Christoph Hellwig 
Reviewed-by: Sagi Grimberg 
Reviewed-by: Chaitanya Kulkarni

nvmet: use flex_array_size and struct_size

2021-10-27T06:06:41+00:00

In an effort to avoid open-coded arithmetic in the kernel [1], use the
flex_array_size() and struct_size() helpers instead of an open-coded
calculation.

[1] https://github.com/KSPP/linux/issues/160

Signed-off-by: Len Baker 
Reviewed-by: Sagi Grimberg 
Reviewed-by: Gustavo A. R. Silva 
Reviewed-by: Chaitanya Kulkarni 
Signed-off-by: Christoph Hellwig

nvmet: use struct_size over open coded arithmetic

2021-10-20T17:23:30+00:00

As noted in the "Deprecated Interfaces, Language Features, Attributes,
and Conventions" documentation [1], size calculations (especially
multiplication) should not be performed in memory allocator (or similar)
function arguments due to the risk of them overflowing. This could lead
to values wrapping around and a smaller allocation being made than the
caller was expecting. Using those allocations could lead to linear
overflows of heap memory and other misbehaviors.

In this case this is not actually dynamic size: all the operands
involved in the calculation are constant values. However it is better to
refactor this anyway, just to keep the open-coded math idiom out of
code.

So, use the struct_size() helper to do the arithmetic instead of the
argument "size + count * size" in the kmalloc() function.

This code was detected with the help of Coccinelle and audited and fixed
manually.

[1] https://www.kernel.org/doc/html/latest/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments

Signed-off-by: Len Baker 
Signed-off-by: Christoph Hellwig

nvmet: use macro definitions for setting cmic value

2021-10-20T17:16:03+00:00

This makes the code more readable.

Signed-off-by: Max Gurtovoy 
Reviewed-by: Chaitanya Kulkarni 
Signed-off-by: Christoph Hellwig

nvmet: use macro definition for setting nmic value

2021-10-20T17:16:02+00:00

This makes the code more readable.

Signed-off-by: Max Gurtovoy 
Reviewed-by: Keith Busch 
Reviewed-by: Sagi Grimberg 
Reviewed-by: Chaitanya Kulkarni 
Signed-off-by: Christoph Hellwig

nvmet: set 'CNTRLTYPE' in the identify controller data

2021-10-20T17:16:02+00:00

Set the correct 'CNTRLTYPE' field in the identify controller data.

Signed-off-by: Hannes Reinecke 
Reviewed-by: Chaitanya Kulkarni 
Signed-off-by: Christoph Hellwig

nvmet: add nvmet_is_disc_subsys() helper

2021-10-20T17:16:02+00:00

Add a helper function to determine if a given subsystem is a discovery
subsystem.

Signed-off-by: Hannes Reinecke 
Reviewed-by: Chaitanya Kulkarni 
Reviewed-by: Himanshu Madhani 
Signed-off-by: Christoph Hellwig

nvmet: return bool from nvmet_passthru_ctrl and nvmet_is_passthru_req

2021-09-06T07:59:03+00:00

The target core code never needs the host-side nvme_ctrl structure.
Open code two uses of nvmet_is_passthru_req in passthru.c, and then
switch the helpers used by the core to return bool.  Also rename the
fuctions to better match their usage:

  nvmet_passthru_ctrl -> nvmet_is_passthru_subsys
  nvmet_req_passthru_ctrl -> nvmet_is_passthru_req

Signed-off-by: Christoph Hellwig 
Reviewed-by: Sagi Grimberg

nvmet: use NVMET_MAX_NAMESPACES to set nn value

2021-06-21T06:34:10+00:00

For Spec regarding MNAN value:-

If the controller supports Asymmetric Namespace Access Reporting, then
this field shall be set to a non-zero value that is less than or equal
to the NN value.

Instead of using subsys->max_nsid that gets calculated dynamically,
use NVMET_MAX_NAMESPACES value to report NN. This way we will maintain
the MNAN value spec compliant with NN.

Without this patch, code results in the following error :-

[337976.409142] nvme nvme1: Invalid MNAN value 1024

Signed-off-by: Chaitanya Kulkarni 
Signed-off-by: Christoph Hellwig