s390/pci: Use dma-iommu layer

While s390 already has a standard IOMMU driver and previous changes have
added I/O TLB flushing operations this driver is currently only used for
user-space PCI access such as vfio-pci. For the DMA API s390 instead
utilizes its own implementation in arch/s390/pci/pci_dma.c which drives
the same hardware and shares some code but requires a complex and
fragile hand over between DMA API and IOMMU API use of a device and
despite code sharing still leads to significant duplication and
maintenance effort. Let's utilize the common code DMAP API
implementation from drivers/iommu/dma-iommu.c instead allowing us to
get rid of arch/s390/pci/pci_dma.c.

Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Link: https://lore.kernel.org/r/20230928-dma_iommu-v13-3-9e5fc4dacc36@linux.ibm.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>

s390/pci: stash dtsm and maxstbl

Store information about what IOAT designation types are supported by
underlying hardware as well as the largest store block size allowed.
These values will be needed by passthrough.

Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com>
Reviewed-by: Pierre Morel <pmorel@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com>
Link: https://lore.kernel.org/r/20220606203325.110625-10-mjrosato@linux.ibm.com
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>

s390/pci: stash associated GISA designation

For passthrough devices, we will need to know the GISA designation of the
guest if interpretation facilities are to be used. Setup to stash this in
the zdev and set a default of 0 (no GISA designation) for now; a subsequent
patch will set a valid GISA designation for passthrough devices.
Also, extend mpcific routines to specify this stashed designation as part
of the mpcific command.

Reviewed-by: Pierre Morel <pmorel@linux.ibm.com>
Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com>
Link: https://lore.kernel.org/r/20220606203325.110625-9-mjrosato@linux.ibm.com
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>

s390/pci: Implement ioremap_wc/prot() with MIO

With our current support for the new MIO PCI instructions, write
combining/write back MMIO memory can be obtained via the pci_iomap_wc()
and pci_iomap_wc_range() functions.
This is achieved by using the write back address for a specific bar
as provided in clp_store_query_pci_fn()

These functions are however not widely used and instead drivers often
rely on ioremap_wc() and ioremap_prot(), which on other platforms enable
write combining using a PTE flag set through the pgrprot value.

While we do not have a write combining flag in the low order flag bits
of the PTE like x86_64 does, with MIO support, there is a write back bit
in the physical address (bit 1 on z15) and thus also the PTE.
Which bit is used to toggle write back and whether it is available at
all, is however not fixed in the architecture. Instead we get this
information from the CLP Store Logical Processor Characteristics for PCI
command. When the write back bit is not provided we fall back to the
existing behavior.

Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Reviewed-by: Pierre Morel <pmorel@linux.ibm.com>
Reviewed-by: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

s390/pci: create links between PFs and VFs

On s390 PCI Virtual Functions (VFs) are scanned by firmware and are made
available to Linux via the hot-plug interface. As such the common code
path of doing the scan directly using the parent Physical Function (PF)
is not used and fenced off with the no_vf_scan attribute.

Even if the partition created the VFs itself e.g. using the sriov_numvfs
attribute of a PF, the PF/VF links thus need to be established after the
fact. To do this when a VF is plugged we scan through all functions on
the same zbus and test whether they are the parent PF in which case we
establish the necessary links.

With these links established there is now no more need to fence off
pci_iov_remove_virtfn() for pdev->no_vf_scan as the common code now
works fine.

Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Pierre Morel <pmorel@linux.ibm.com>
Link: https://lore.kernel.org/r/20200506154139.90609-3-schnelle@linux.ibm.com
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

s390/pci: define RID and RID available

Firmware provides the bus/devfn part of the PCI addresses of a zPCI
function inside the new field RID of the CLP query PCI function
with a bit to know if this field is available to use.

Let's add these fields to the clp_rsp_query_pci structure,
add corresponding fields to zdev and initialize them.

Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

s390/pci: Expose new port attribute for PCIe functions

Add SysFS attribute that provides the port number for PCI functions
representing a single port of a multi-port device.

Signed-off-by: Alexander Schmidt <alexs@linux.ibm.com>
Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

PCI: Add PCI_STD_NUM_BARS for the number of standard BARs

Code that iterates over all standard PCI BARs typically uses
PCI_STD_RESOURCE_END. However, that requires the unusual test
"i <= PCI_STD_RESOURCE_END" rather than something the typical
"i < PCI_STD_NUM_BARS".

Add a definition for PCI_STD_NUM_BARS and change loops to use the more
idiomatic C style to help avoid fencepost errors.

Link: https://lore.kernel.org/r/20190927234026.23342-1-efremov@linux.com
Link: https://lore.kernel.org/r/20190927234308.23935-1-efremov@linux.com
Link: https://lore.kernel.org/r/20190916204158.6889-3-efremov@linux.com
Signed-off-by: Denis Efremov <efremov@linux.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Sebastian Ott <sebott@linux.ibm.com> # arch/s390/
Acked-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> # video/fbdev/
Acked-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com> # pci/controller/dwc/
Acked-by: Jack Wang <jinpu.wang@cloud.ionos.com> # scsi/pm8001/
Acked-by: Martin K. Petersen <martin.petersen@oracle.com> # scsi/pm8001/
Acked-by: Ulf Hansson <ulf.hansson@linaro.org> # memstick/

s390/pci: fix struct definition for set PCI function

Recent firmware will store PCI MIO information also when enabling MIO
instructions via set PCI function. We do not use this information but
currently calling enable MIO will fail because of insufficient response
block length. Fix this by putting a struct mio_info at the end of the
affected response block struct.

Fixes: 71ba41c9b1d9 ("s390/pci: provide support for MIO instructions")
Signed-off-by: Sebastian Ott <sebott@linux.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

s390/pci: provide support for MIO instructions

Provide support for PCI I/O instructions that work on mapped IO addresses.

Signed-off-by: Sebastian Ott <sebott@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/pci: provide support for CPU directed interrupts

Up until now all interrupts on s390 have been floating. For MSI interrupts
we've used a global summary bit vector (with a bit for each function) and
a per-function interrupt bit vector (with a bit per MSI).

This patch introduces a new IRQ delivery mode: CPU directed interrupts.
In this new mode a per-CPU interrupt bit vector is used (with a bit per
MSI per function). Further it is now possible to direct an IRQ to a
specific CPU so we can finally support IRQ affinity.

If an interrupt can't be delivered because the appointed CPU is occupied
by a hypervisor the interrupt is delivered floating. For this a global
summary bit vector is used (with a bit per CPU).

Signed-off-by: Sebastian Ott <sebott@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.

For non */uapi/* files that summary was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139

and resulted in the first patch in this series.

If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930

and resulted in the second patch in this series.

- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:

SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1

and that resulted in the third patch in this series.

- when the two scanners agreed on the detected license(s), that became
the concluded license(s).

- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.

- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).

- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.

- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct

This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

s390/pci: use proper endianness annotations

Add proper annotation to the bar definition and use casts within the
bus accessors. Also change the sequence in the accessors to do the
shifts in the native byte order. No functional change.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/pci: query fmb length

Query the length of the fmb and abort fmb registration if the
size of the associated measurement block is too small.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/pci: use unique UIDs for domain enumeration

Use UIDs as domain numbers if the UID checking rules apply (in this
case the FW guarantees uniqueness of these values).

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/pci: add ioctl interface for CLP

Provide a user space interface to issue call logical-processor instructions.
Only selected CLP commands are allowed, enough to get the full overview of
the installed PCI functions.

Reviewed-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/pci: add some new arch specific pci attributes

Add a bunch of s390 specific pci attributes to help
identifying pci functions.

Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/pci: CLP interface

CLP instructions are used to query the firmware about detected PCI
functions, the attributes of those functions and to enable or disable
a PCI function. The CLP interface is the equivalent to a PCI bus scan.

Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>