scsi: fnic: Modify ISRs to support multiqueue (MQ)

Modify interrupt service routines for INTx, MSI, and MSI-x to support
multiqueue. Modify parameter list of fnic_wq_copy_cmpl_handler to take
cq_index. Modify fnic_cleanup function to use the new function call of
fnic_wq_copy_cmpl_handler. Refactor code to set interrupt mode to MSI-x to
a new function. Add a new stat for intx_dummy.

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202310251847.4T8BVZAZ-lkp@intel.com/
Reviewed-by: Sesidhar Baddela <sebaddel@cisco.com>
Reviewed-by: Arulprabhu Ponnusamy <arulponn@cisco.com>
Signed-off-by: Karan Tilak Kumar <kartilak@cisco.com>
Link: https://lore.kernel.org/r/20231211173617.932990-8-kartilak@cisco.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: fnic: Rename wq_copy to hw_copy_wq

Rename wq_copy to hw_copy_wq to accurately describe the copy
workqueue. This will also help distinguish this data structure from
software data structures that can be introduced.

Reviewed-by: Sesidhar Baddela <sebaddel@cisco.com>
Reviewed-by: Arulprabhu Ponnusamy <arulponn@cisco.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Karan Tilak Kumar <kartilak@cisco.com>
Link: https://lore.kernel.org/r/20231211173617.932990-5-kartilak@cisco.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

treewide: Replace GPLv2 boilerplate/reference with SPDX - gpl-2.0_168.RULE (part 1)

Based on the normalized pattern:

this program is free software you may redistribute it and/or modify it
under the terms of the gnu general public license as published by the
free software foundation version 2 of the license the software is
provided as is without warranty of any kind express or implied
including but not limited to the warranties of merchantability fitness
for a particular purpose and noninfringement in no event shall the
authors or copyright holders be liable for any claim damages or other
liability whether in an action of contract tort or otherwise arising
from out of or in connection with the software or the use or other
dealings in the software

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

scsi: fnic: fix msix interrupt allocation

pci_alloc_irq_vectors() returns number of vectors allocated. Fix the check
for error condition.

Fixes: cca678dfbad49 ("scsi: fnic: switch to pci_alloc_irq_vectors")
Link: https://lore.kernel.org/r/20190827211340.1095-1-gvaradar@cisco.com
Signed-off-by: Govindarajulu Varadarajan <gvaradar@cisco.com>
Acked-by: Satish Kharat <satishkh@cisco.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: fnic: Impose upper limit on max. # of CQs processed per intr

Impose an upper limit on the max number of CQ entries (corresponding to the
copy wq) processed in an interrupt. Use module parameter to set the limit.

Signed-off-by: Satish Kharat <satishkh@cisco.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: fnic: switch to pci_alloc_irq_vectors

Not a full cleanup for the IRQ code, for that we'd need to know if the
max number of the various CQ types is going to stay 1 forever.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Satish Kharat <satishkh@cisco.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

fnic: Use pci_enable_msix_exact() instead of pci_enable_msix()

As result of deprecation of MSI-X/MSI enablement functions
pci_enable_msix() and pci_enable_msi_block() all drivers
using these two interfaces need to be updated to use the
new pci_enable_msi_range() or pci_enable_msi_exact()
and pci_enable_msix_range() or pci_enable_msix_exact()
interfaces.

Signed-off-by: Alexander Gordeev <agordeev@redhat.com>
Acked-by: "Suma Ramars (sramars)" <sramars@cisco.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

[SCSI] fnic: Fnic Statistics Collection

This feature gathers active and cumulative per fnic stats for io,
abort, terminate, reset, vlan discovery path and it also includes
various important stats for debugging issues. It also provided
debugfs and ioctl interface for user to retrieve these stats.
It also provides functionality to reset cumulative stats through
user interface.

Signed-off-by: Hiral Patel <hiralpat@cisco.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

[SCSI] fnic: Process all cq entries per ISR

Driver was processing a fixed max number of cq descriptors per ISR. For
instance, for the SCSI IO queue, number of IOs processed per ISR were 8.
If hardware writes 9 cq descriptors to the cq and generates an interrupt,
driver would process only 8 descriptors and decrement the outstanding
credit count by 8. Unless another interrupt event happens, the hw does
not generate any additional interrupt. This results in the cq descriptor
sitting in the queue without being procesed and can cause IO timeouts
and aborts.

Modify all ISR functions to process all queued cq descriptors in one shot.
Since bulk of ELS frame processing is done in thread context and bulk
of SCSI IO processing is done in soft ISR deferred context, the cycles
spent in the ISR per cq descriptor is small.

Signed-off-by: Herman Lee <hermlee@cisco.com>
Signed-off-by: Abhijeet Joglekar <abjoglek@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>

[SCSI] fnic: Add new Cisco PCI-Express FCoE HBA

fnic is a driver for the Cisco PCI-Express FCoE HBA

Signed-off-by: Abhijeet Joglekar <abjoglek@cisco.com>
Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>