Commit Graph

8 Commits

Author SHA1 Message Date
Christoph Hellwig b4dca15129 swiotlb-xen: simplify cache maintainance
Now that we know we always have the dma-noncoherent.h helpers available
if we are on an architecture with support for non-coherent devices,
we can just call them directly, and remove the calls to the dma-direct
routines, including the fact that we call the dma_direct_map_page
routines but ignore the value returned from it.  Instead we now have
Xen wrappers for the arch_sync_dma_for_{device,cpu} helpers that call
the special Xen versions of those routines for foreign pages.

Note that the new helpers get the physical address passed in addition
to the dma address to avoid another translation for the local cache
maintainance.  The pfn_valid checks remain on the dma address as in
the old code, even if that looks a little funny.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2019-09-11 12:43:27 +02:00
Christoph Hellwig c9b6180dbf swiotlb-xen: use the same foreign page check everywhere
xen_dma_map_page uses a different and more complicated check for foreign
pages than the other three cache maintainance helpers.  Switch it to the
simpler pfn_valid method a well, and document the scheme with a single
improved comment in xen_dma_map_page.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
2019-09-11 12:43:27 +02:00
Christoph Hellwig bef4d2037d xen/arm: consolidate page-coherent.h
Shared the duplicate arm/arm64 code in include/xen/arm/page-coherent.h.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
2019-09-11 12:43:22 +02:00
Christoph Hellwig 60d8cd572f arm64/xen: fix xen-swiotlb cache flushing
Xen-swiotlb hooks into the arm/arm64 arch code through a copy of the DMA
DMA mapping operations stored in the struct device arch data.

Switching arm64 to use the direct calls for the merged DMA direct /
swiotlb code broke this scheme.  Replace the indirect calls with
direct-calls in xen-swiotlb as well to fix this problem.

Fixes: 356da6d0cd ("dma-mapping: bypass indirect calls for dma-direct")
Reported-by: Julien Grall <julien.grall@arm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
2019-01-23 22:14:56 +01:00
Greg Kroah-Hartman b24413180f 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>
2017-11-02 11:10:55 +01:00
Stefano Stabellini d5ff5061c3 xen/arm,arm64: rename __generic_dma_ops to xen_get_dma_ops
Now that __generic_dma_ops is a xen specific function, rename it to
xen_get_dma_ops. Change all the call sites appropriately.

Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
CC: linux@armlinux.org.uk
CC: catalin.marinas@arm.com
CC: will.deacon@arm.com
CC: boris.ostrovsky@oracle.com
CC: jgross@suse.com
CC: Julien Grall <julien.grall@arm.com>
2017-05-02 11:14:47 +02:00
Stefano Stabellini e058632670 xen/arm,arm64: fix xen_dma_ops after 815dd18 "Consolidate get_dma_ops..."
The following commit:

  commit 815dd18788
  Author: Bart Van Assche <bart.vanassche@sandisk.com>
  Date:   Fri Jan 20 13:04:04 2017 -0800

      treewide: Consolidate get_dma_ops() implementations

rearranges get_dma_ops in a way that xen_dma_ops are not returned when
running on Xen anymore, dev->dma_ops is returned instead (see
arch/arm/include/asm/dma-mapping.h:get_arch_dma_ops and
include/linux/dma-mapping.h:get_dma_ops).

Fix the problem by storing dev->dma_ops in dev_archdata, and setting
dev->dma_ops to xen_dma_ops. This way, xen_dma_ops is returned naturally
by get_dma_ops. The Xen code can retrieve the original dev->dma_ops from
dev_archdata when needed. It also allows us to remove __generic_dma_ops
from common headers.

Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
Tested-by: Julien Grall <julien.grall@arm.com>
Suggested-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: <stable@vger.kernel.org>        [4.11+]
CC: linux@armlinux.org.uk
CC: catalin.marinas@arm.com
CC: will.deacon@arm.com
CC: boris.ostrovsky@oracle.com
CC: jgross@suse.com
CC: Julien Grall <julien.grall@arm.com>
2017-05-02 11:14:42 +02:00
Marc Zyngier 2fbadc3002 arm/arm64: xen: Move shared architecture headers to include/xen/arm
ARM and arm64 Xen ports share a number of headers, leading to
packaging issues when these headers needs to be exported, as it
breaks the reasonable requirement that an architecture port
has self-contained headers.

Fix the issue by moving the 5 header files to include/xen/arm,
and keep local placeholders to include the relevant files.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
2016-12-02 11:49:55 -08:00