pds_core: delete VF dev on reset

When the VF is hit with a reset, remove the aux device in
the prepare for reset and try to restore it after the reset.
The userland mechanics will need to recover and rebuild whatever
uses the device afterwards.

Reviewed-by: Brett Creeley <brett.creeley@amd.com>
Signed-off-by: Shannon Nelson <shannon.nelson@amd.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: pds_core: Fix possible double free in error handling path

When auxiliary_device_add() returns error and then calls
auxiliary_device_uninit(), Callback function pdsc_auxbus_dev_release
calls kfree(padev) to free memory. We shouldn't call kfree(padev)
again in the error handling path.

Fix this by cleaning up the redundant kfree() and putting
the error handling back to where the errors happened.

Fixes: 4569cce43bc6 ("pds_core: add auxiliary_bus devices")
Signed-off-by: Yongzhi Liu <hyperlyzcs@gmail.com>
Reviewed-by: Wojciech Drewek <wojciech.drewek@intel.com>
Reviewed-by: Shannon Nelson <shannon.nelson@amd.com>
Link: https://lore.kernel.org/r/20240306105714.20597-1-hyperlyzcs@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

Revert "pds_core: Fix some kernel-doc comments"

This reverts commit cb39c35783f26892bb1a72b1115c94fa2e77f4c5.
Patch was applied to hastily, the problem is already fixed
in Alex's vfio tree:
https://lore.kernel.org/all/20230821112237.105872b5.alex.williamson@redhat.com/

Signed-off-by: Jakub Kicinski <kuba@kernel.org>

pds_core: Fix some kernel-doc comments

Fix some kernel-doc comments to silence the warnings:

drivers/net/ethernet/amd/pds_core/auxbus.c:18: warning: Function parameter or member 'pf' not described in 'pds_client_register'
drivers/net/ethernet/amd/pds_core/auxbus.c:18: warning: Excess function parameter 'pf_pdev' description in 'pds_client_register'
drivers/net/ethernet/amd/pds_core/auxbus.c:58: warning: Function parameter or member 'pf' not described in 'pds_client_unregister'
drivers/net/ethernet/amd/pds_core/auxbus.c:58: warning: Excess function parameter 'pf_pdev' description in 'pds_client_unregister'

Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

pds_core: Fix function header descriptions

The pds-vfio-pci series made a small interface change to
pds_client_register() and pds_client_unregister(), but forgot to update
the function header descriptions. Fix that.

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202308180411.OSqJPtMz-lkp@intel.com/
Fixes: b021d05e106e ("pds_core: Require callers of register/unregister to pass PF drvdata")
Signed-off-by: Shannon Nelson <shannon.nelson@amd.com>
Signed-off-by: Brett Creeley <brett.creeley@amd.com>
Link: https://lore.kernel.org/r/20230817224212.14266-1-brett.creeley@amd.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

pds_core: Require callers of register/unregister to pass PF drvdata

Pass a pointer to the PF's private data structure rather than
bouncing in and out of the PF's PCI function address.

Signed-off-by: Shannon Nelson <shannon.nelson@amd.com>
Signed-off-by: Brett Creeley <brett.creeley@amd.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20230807205755.29579-4-brett.creeley@amd.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

pds_core: Fix documentation for pds_client_register

The documentation above pds_client_register states that it returns 0 on
success and negative on error. However, it actually returns a positive
client ID on success and negative on error. Fix the documentation to
state exactly that.

Signed-off-by: Brett Creeley <brett.creeley@amd.com>
Signed-off-by: Shannon Nelson <shannon.nelson@amd.com>
Reviewed-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Link: https://lore.kernel.org/r/20230801165833.1622-1-brett.creeley@amd.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

pds_core: add the aux client API

Add the client API operations for running adminq commands.
The core registers the client with the FW, then the client
has a context for requesting adminq services. We expect
to add additional operations for other clients, including
requesting additional private adminqs and IRQs, but don't have
the need yet.

Signed-off-by: Shannon Nelson <shannon.nelson@amd.com>
Acked-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

pds_core: add auxiliary_bus devices

An auxiliary_bus device is created for each vDPA type VF at VF
probe and destroyed at VF remove. The aux device name comes
from the driver name + VIF type + the unique id assigned at PCI
probe. The VFs are always removed on PF remove, so there should
be no issues with VFs trying to access missing PF structures.

The auxiliary_device names will look like "pds_core.vDPA.nn"
where 'nn' is the VF's uid.

Signed-off-by: Shannon Nelson <shannon.nelson@amd.com>
Acked-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>