Commit Graph

62 Commits

Author SHA1 Message Date
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
Arnd Bergmann
9cc91f2121 xen: avoid type warning in xchg_xen_ulong
The improved type-checking version of container_of() triggers a warning for
xchg_xen_ulong, pointing out that 'xen_ulong_t' is unsigned, but atomic64_t
contains a signed value:

drivers/xen/events/events_2l.c: In function 'evtchn_2l_handle_events':
drivers/xen/events/events_2l.c:187:1020: error: call to '__compiletime_assert_187' declared with attribute error: pointer type mismatch in container_of()

This adds a cast to work around the warning.

Cc: Ian Abbott <abbotti@mev.co.uk>
Fixes: 85323a991d ("xen: arm: mandate EABI and use generic atomic operations.")
Fixes: daa2ac80834d ("kernel.h: handle pointers to arrays better in container_of()")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Acked-by: Ian Abbott <abbotti@mev.co.uk>
2017-06-08 15:07:38 -07:00
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
Krzysztof Kozlowski
00085f1efa dma-mapping: use unsigned long for dma_attrs
The dma-mapping core and the implementations do not change the DMA
attributes passed by pointer.  Thus the pointer can point to const data.
However the attributes do not have to be a bitfield.  Instead unsigned
long will do fine:

1. This is just simpler.  Both in terms of reading the code and setting
   attributes.  Instead of initializing local attributes on the stack
   and passing pointer to it to dma_set_attr(), just set the bits.

2. It brings safeness and checking for const correctness because the
   attributes are passed by value.

Semantic patches for this change (at least most of them):

    virtual patch
    virtual context

    @r@
    identifier f, attrs;

    @@
    f(...,
    - struct dma_attrs *attrs
    + unsigned long attrs
    , ...)
    {
    ...
    }

    @@
    identifier r.f;
    @@
    f(...,
    - NULL
    + 0
     )

and

    // Options: --all-includes
    virtual patch
    virtual context

    @r@
    identifier f, attrs;
    type t;

    @@
    t f(..., struct dma_attrs *attrs);

    @@
    identifier r.f;
    @@
    f(...,
    - NULL
    + 0
     )

Link: http://lkml.kernel.org/r/1468399300-5399-2-git-send-email-k.kozlowski@samsung.com
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Acked-by: Robin Murphy <robin.murphy@arm.com>
Acked-by: Hans-Christian Noren Egtvedt <egtvedt@samfundet.no>
Acked-by: Mark Salter <msalter@redhat.com> [c6x]
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com> [cris]
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch> [drm]
Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com>
Acked-by: Joerg Roedel <jroedel@suse.de> [iommu]
Acked-by: Fabien Dessenne <fabien.dessenne@st.com> [bdisp]
Reviewed-by: Marek Szyprowski <m.szyprowski@samsung.com> [vb2-core]
Acked-by: David Vrabel <david.vrabel@citrix.com> [xen]
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> [xen swiotlb]
Acked-by: Joerg Roedel <jroedel@suse.de> [iommu]
Acked-by: Richard Kuo <rkuo@codeaurora.org> [hexagon]
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> [m68k]
Acked-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> [s390]
Acked-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Acked-by: Hans-Christian Noren Egtvedt <egtvedt@samfundet.no> [avr32]
Acked-by: Vineet Gupta <vgupta@synopsys.com> [arc]
Acked-by: Robin Murphy <robin.murphy@arm.com> [arm64 and dma-iommu]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-04 08:50:07 -04:00
Juergen Gross
4b5ae0150f arm/xen: add support for vm_assist hypercall
Add support for the Xen HYPERVISOR_vm_assist hypercall.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-07-06 10:42:14 +01:00
Shannon Zhao
be1aaf4e40 ARM64: XEN: Add a function to initialize Xen specific UEFI runtime services
When running on Xen hypervisor, runtime services are supported through
hypercall. Add a Xen specific function to initialize runtime services.

Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Tested-by: Julien Grall <julien.grall@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
2016-07-06 10:34:46 +01:00
Linus Torvalds
55fc733c7e xen: features and fixes for 4.6-rc0
- Make earlyprintk=xen work for HVM guests.
 - Remove module support for things never built as modules.
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Merge tag 'for-linus-4.6-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen updates from David Vrabel:
 "Features and fixes for 4.6:

  - Make earlyprintk=xen work for HVM guests

  - Remove module support for things never built as modules"

* tag 'for-linus-4.6-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  drivers/xen: make platform-pci.c explicitly non-modular
  drivers/xen: make sys-hypervisor.c explicitly non-modular
  drivers/xen: make xenbus_dev_[front/back]end explicitly non-modular
  drivers/xen: make [xen-]ballon explicitly non-modular
  xen: audit usages of module.h ; remove unnecessary instances
  xen/x86: Drop mode-selecting ifdefs in startup_xen()
  xen/x86: Zero out .bss for PV guests
  hvc_xen: make early_printk work with HVM guests
  hvc_xen: fix xenboot for DomUs
  hvc_xen: add earlycon support
2016-03-22 12:55:17 -07:00
Paul Gortmaker
59aa56bf2a xen: audit usages of module.h ; remove unnecessary instances
Code that uses no modular facilities whatsoever should not be
sourcing module.h at all, since that header drags in a bunch
of other headers with it.

Similarly, code that is not explicitly using modular facilities
like module_init() but only is declaring module_param setup
variables should be using moduleparam.h and not the larger
module.h file for that.

In making this change, we also uncover an implicit use of BUG()
in inline fcns within arch/arm/include/asm/xen/hypercall.h so
we explicitly source <linux/bug.h> for that file now.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-03-21 15:13:32 +00:00
Ian Campbell
52ba0746b3 xen/arm: correctly handle DMA mapping of compound pages
Currently xen_dma_map_page concludes that DMA to anything other than
the head page of a compound page must be foreign, since the PFN of the
page is that of the head.

Fix the check to instead consider the whole of a compound page to be
local if the PFN of the head passes the 1:1 check.

We can never see a compound page which is a mixture of foreign and
local sub-pages.

The comment already correctly described the intention, but fixup the
spelling and some grammar.

This fixes the various SSH protocol errors which we have been seeing
on the cubietrucks in our automated test infrastructure.

This has been broken since commit 3567258d28 ("xen/arm: use
hypercall to flush caches in map_page"), which was in v3.19-rc1.

NB arch/arm64/.../xen/page-coherent.h also includes this file.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Cc: xen-devel@lists.xenproject.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: stable@vger.kernel.org # v3.19+
2016-02-08 17:19:27 +00:00
Stefano Stabellini
ab76078a3d arm: extend pvclock_wall_clock with sec_hi
The hypervisor actually exposes an additional field to struct
pvclock_wall_clock, with the high 32 bit seconds.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Julien Grall <julien.grall@citrix.com>
2015-12-21 14:40:57 +00:00
Stefano Stabellini
72d39c691b xen/arm: introduce HYPERVISOR_platform_op on arm and arm64
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
2015-12-21 14:40:56 +00:00
Stefano Stabellini
a314e3eb84 xen/arm: Enable cpu_hotplug.c
Build cpu_hotplug for ARM and ARM64 guests.

Rename arch_(un)register_cpu to xen_(un)register_cpu and provide an
empty implementation on ARM and ARM64. On x86 just call
arch_(un)register_cpu as we are already doing.

Initialize cpu_hotplug on ARM.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Julien Grall <julien.grall@citrix.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2015-10-23 14:20:47 +01:00
Julien Grall
9435cce879 xen/swiotlb: Add support for 64KB page granularity
Swiotlb is used on ARM64 to support DMA on platform where devices are
not protected by an SMMU. Furthermore it's only enabled for DOM0.

While Xen is always using 4KB page granularity in the stage-2 page table,
Linux ARM64 may either use 4KB or 64KB. This means that a Linux page
can be spanned accross multiple Xen page.

The Swiotlb code has to validate that the buffer used for DMA is
physically contiguous in the memory. As a Linux page can't be shared
between local memory and foreign page by design (the balloon code always
removing entirely a Linux page), the changes in the code are very
minimal because we only need to check the first Xen PFN.

Note that it may be possible to optimize the function
check_page_physically_contiguous to avoid looping over every Xen PFN
for local memory. Although I will let this optimization for a follow-up.

Signed-off-by: Julien Grall <julien.grall@citrix.com>
Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-10-23 14:20:43 +01:00
Julien Grall
291be10fd7 xen/swiotlb: Pass addresses rather than frame numbers to xen_arch_need_swiotlb
With 64KB page granularity support, the frame number will be different.

It will be easier to modify the behavior in a single place rather than
in each caller.

Signed-off-by: Julien Grall <julien.grall@citrix.com>
Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-10-23 14:20:43 +01:00
Julien Grall
250c9af3d8 arm/xen: Add support for 64KB page granularity
The hypercall interface is always using 4KB page granularity. This is
requiring to use xen page definition macro when we deal with hypercall.

Note that pfn_to_gfn is working with a Xen pfn (i.e 4KB). We may want to
rename pfn_gfn to make this explicit.

We also allocate a 64KB page for the shared page even though only the
first 4KB is used. I don't think this is really important for now as it
helps to have the pointer 4KB aligned (XENMEM_add_to_physmap is taking a
Xen PFN).

Signed-off-by: Julien Grall <julien.grall@citrix.com>
Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-10-23 14:20:42 +01:00
Julien Grall
5031612b5e arm/xen: Drop pte_mfn and mfn_pte
They are not used in common code expect in one place in balloon.c which is
only compiled when Linux is using PV MMU. It's not the case on ARM.

Rather than worrying how to handle the 64KB case, drop them.

Signed-off-by: Julien Grall <julien.grall@citrix.com>
Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-10-23 14:20:32 +01:00
Julien Grall
0df4f266b3 xen: Use correctly the Xen memory terminologies
Based on include/xen/mm.h [1], Linux is mistakenly using MFN when GFN
is meant, I suspect this is because the first support for Xen was for
PV. This resulted in some misimplementation of helpers on ARM and
confused developers about the expected behavior.

For instance, with pfn_to_mfn, we expect to get an MFN based on the name.
Although, if we look at the implementation on x86, it's returning a GFN.

For clarity and avoid new confusion, replace any reference to mfn with
gfn in any helpers used by PV drivers. The x86 code will still keep some
reference of pfn_to_mfn which may be used by all kind of guests
No changes as been made in the hypercall field, even
though they may be invalid, in order to keep the same as the defintion
in xen repo.

Note that page_to_mfn has been renamed to xen_page_to_gfn to avoid a
name to close to the KVM function gfn_to_page.

Take also the opportunity to simplify simple construction such
as pfn_to_mfn(page_to_pfn(page)) into xen_page_to_gfn. More complex clean up
will come in follow-up patches.

[1] http://xenbits.xen.org/gitweb/?p=xen.git;a=commitdiff;h=e758ed14f390342513405dd766e874934573e6cb

Signed-off-by: Julien Grall <julien.grall@citrix.com>
Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-09-08 18:03:49 +01:00
Julien Grall
5192b35de4 arm/xen: implement correctly pfn_to_mfn
After the commit introducing convertion between DMA and guest addresses,
all the callers of pfn_to_mfn are expecting to get a GFN (Guest Frame
Number). On ARM, all the guests are auto-translated so the GFN is equal
to the Linux PFN (Pseudo-physical Frame Number).

The current implementation may return an MFN if the caller is passing a
PFN associated to a mapped foreign grant. In pratice, I haven't seen
the problem on running guest but we should fix it for the sake of
correctness.

Correct the implementation by always returning the pfn passed in parameter.

A follow-up patch will take care to rename pfn_to_mfn to a suitable
name.

Signed-off-by: Julien Grall <julien.grall@citrix.com>
Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-09-08 17:10:52 +01:00
Julien Grall
32e09870ee xen: Make clear that swiotlb and biomerge are dealing with DMA address
The swiotlb is required when programming a DMA address on ARM when a
device is not protected by an IOMMU.

In this case, the DMA address should always be equal to the machine address.
For DOM0 memory, Xen ensure it by have an identity mapping between the
guest address and host address. However, when mapping a foreign grant
reference, the 1:1 model doesn't work.

For ARM guest, most of the callers of pfn_to_mfn expects to get a GFN
(Guest Frame Number), i.e a PFN (Page Frame Number) from the Linux point
of view given that all ARM guest are auto-translated.

Even though the name pfn_to_mfn is misleading, we need to ensure that
those caller get a GFN and not by mistake a MFN. In pratical, I haven't
seen error related to this but we should fix it for the sake of
correctness.

In order to fix the implementation of pfn_to_mfn on ARM in a follow-up
patch, we have to introduce new helpers to return the DMA from a PFN and
the invert.

On x86, the new helpers will be an alias of pfn_to_mfn and mfn_to_pfn.

The helpers will be used in swiotlb and xen_biovec_phys_mergeable.

This is necessary in the latter because we have to ensure that the
biovec code will not try to merge a biovec using foreign page and
another using Linux memory.

Lastly, the helper mfn_to_local_pfn has been renamed to bfn_to_local_pfn
given that the only usage was in swiotlb.

Signed-off-by: Julien Grall <julien.grall@citrix.com>
Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-09-08 17:10:52 +01:00
Julien Grall
724afaea20 arm/xen: Remove helpers which are PV specific
ARM guests are always HVM. The current implementation is assuming a 1:1
mapping which is only true for DOM0 and may not be at all in the future.

Furthermore, all the helpers but arbitrary_virt_to_machine are used in
x86 specific code (or only compiled for).

The helper arbitrary_virt_to_machine is only used in PV specific code.
Therefore we should never call the function.

Add a BUG() in this helper and drop all the others.

Signed-off-by: Julien Grall <julien.grall@citrix.com>
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-08-20 12:25:27 +01:00
Julien Grall
4a5b69464e xen/events: Support event channel rebind on ARM
Currently, the event channel rebind code is gated with the presence of
the vector callback.

The virtual interrupt controller on ARM has the concept of per-CPU
interrupt (PPI) which allow us to support per-VCPU event channel.
Therefore there is no need of vector callback for ARM.

Xen is already using a free PPI to notify the guest VCPU of an event.
Furthermore, the xen code initialization in Linux (see
arch/arm/xen/enlighten.c) is requesting correctly a per-CPU IRQ.

Introduce new helper xen_support_evtchn_rebind to allow architecture
decide whether rebind an event is support or not. It will always return
true on ARM and keep the same behavior on x86.

This is also allow us to drop the usage of xen_have_vector_callback
entirely in the ARM code.

Signed-off-by: Julien Grall <julien.grall@citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-08-20 12:24:15 +01:00
Julien Grall
90d73c4f43 arm/xen: Drop duplicate define mfn_to_virt
Signed-off-by: Julien Grall <julien.grall@citrix.com>
Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-06-17 16:35:17 +01:00
Stefano Stabellini
5882bfef63 arm,arm64/xen: move Xen initialization earlier
Currently, Xen is initialized/discovered in an initcall. This doesn't
allow us to support earlyprintk or choosing the preferred console when
running on Xen.

The current function xen_guest_init is now split in 2 parts:
    - xen_early_init: Check if there is a Xen node in the device tree
    and setup domain type
    - xen_guest_init: Retrieve the information from the device node and
    initialize Xen (grant table, shared page...)

The former is called in setup_arch, while the latter is an initcall.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Julien Grall <julien.grall@linaro.org>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Will Deacon <will.deacon@arm.com>
2015-05-28 12:23:11 +01:00
Stefano Stabellini
8746515d7f xen: Add __GFP_DMA flag when xen_swiotlb_init gets free pages on ARM
Make sure that xen_swiotlb_init allocates buffers that are DMA capable
when at least one memblock is available below 4G. Otherwise we assume
that all devices on the SoC can cope with >4G addresses. We do this on
ARM and ARM64, where dom0 is mapped 1:1, so pfn == mfn in this case.

No functional changes on x86.

From: Chen Baozi <baozich@gmail.com>

Signed-off-by: Chen Baozi <baozich@gmail.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Tested-by: Chen Baozi <baozich@gmail.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-05-06 15:02:58 +01:00
David Vrabel
853d028934 xen/grant-table: pre-populate kernel unmap ops for xen_gnttab_unmap_refs()
When unmapping grants, instead of converting the kernel map ops to
unmap ops on the fly, pre-populate the set of unmap ops.

This allows the grant unmap for the kernel mappings to be trivially
batched in the future.

Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
2015-01-28 14:03:10 +00:00
Stefano Stabellini
a4dba13089 xen/arm/arm64: introduce xen_arch_need_swiotlb
Introduce an arch specific function to find out whether a particular dma
mapping operation needs to bounce on the swiotlb buffer.

On ARM and ARM64, if the page involved is a foreign page and the device
is not coherent, we need to bounce because at unmap time we cannot
execute any required cache maintenance operations (we don't know how to
find the pfn from the mfn).

No change of behaviour for x86.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2014-12-04 12:41:54 +00:00
Stefano Stabellini
3567258d28 xen/arm: use hypercall to flush caches in map_page
In xen_dma_map_page, if the page is a local page, call the native
map_page dma_ops. If the page is foreign, call __xen_dma_map_page that
issues any required cache maintenane operations via hypercall.

The reason for doing this is that the native dma_ops map_page could
allocate buffers than need to be freed. If the page is foreign we don't
call the native unmap_page dma_ops function, resulting in a memory leak.

Suggested-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
2014-12-04 12:41:52 +00:00
Stefano Stabellini
a0f2dee0cd xen: add a dma_addr_t dev_addr argument to xen_dma_map_page
dev_addr is the machine address of the page.

The new parameter can be used by the ARM and ARM64 implementations of
xen_dma_map_page to find out if the page is a local page (pfn == mfn) or
a foreign page (pfn != mfn).

dev_addr could be retrieved again from the physical address, using
pfn_to_mfn, but it requires accessing an rbtree. Since we already have
the dev_addr in our hands at the call site there is no need to get the
mfn twice.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2014-12-04 12:41:51 +00:00
Stefano Stabellini
2f91fc331a xen/arm: if(pfn_valid(pfn)) call native dma_ops
Remove code duplication in mm32.c by calling the native dma_ops if the
page is a local page (not a foreign page). Use a simple pfn_valid(pfn)
check to figure out if the page is local, exploiting the fact that dom0
is mapped 1:1, therefore pfn_valid always returns false when called on a
foreign mfn.

Suggested-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
2014-12-04 12:41:48 +00:00
Stefano Stabellini
d50582e06f xen/arm: remove mach_to_phys rbtree
Remove the rbtree used to keep track of machine to physical mappings:
the frontend can grant the same page multiple times, leading to errors
inserting or removing entries from the mach_to_phys tree.

Linux only needed to know the physical address corresponding to a given
machine address in swiotlb-xen. Now that swiotlb-xen can call the
xen_dma_* functions passing the machine address directly, we can remove
it.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Tested-by: Denis Schneider <v1ne2go@gmail.com>
2014-09-11 18:11:53 +00:00
Stefano Stabellini
340720be32 xen/arm: reimplement xen_dma_unmap_page & friends
xen_dma_unmap_page, xen_dma_sync_single_for_cpu and
xen_dma_sync_single_for_device are currently implemented by calling into
the corresponding generic ARM implementation of these functions. In
order to do this, firstly the dma_addr_t handle, that on Xen is a
machine address, needs to be translated into a physical address.  The
operation is expensive and inaccurate, given that a single machine
address can correspond to multiple physical addresses in one domain,
because the same page can be granted multiple times by the frontend.

To avoid this problem, we introduce a Xen specific implementation of
xen_dma_unmap_page, xen_dma_sync_single_for_cpu and
xen_dma_sync_single_for_device, that can operate on machine addresses
directly.

The new implementation relies on the fact that the hypervisor creates a
second p2m mapping of any grant pages at physical address == machine
address of the page for dom0. Therefore we can access memory at physical
address == dma_addr_r handle and perform the cache flushing there. Some
cache maintenance operations require a virtual address. Instead of using
ioremap_cache, that is not safe in interrupt context, we allocate a
per-cpu PAGE_KERNEL scratch page and we manually update the pte for it.

arm64 doesn't need cache maintenance operations on unmap for now.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Tested-by: Denis Schneider <v1ne2go@gmail.com>
2014-09-11 18:11:53 +00:00
Stefano Stabellini
79390289cf arm,arm64/xen: introduce HYPERVISOR_suspend()
Introduce HYPERVISOR_suspend() and a few additional empty stubs for
Xen arch specific functions called by drivers/xen/manage.c.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2014-05-12 17:20:24 +01:00
Julien Grall
adc01864eb arm/xen: Remove definiition of virt_to_pfn in asm/xen/page.h
virt_to_pfn has been defined in asm/memory.h by the commit e26a9e0 "ARM: Better
virt_to_page() handling"

This will result of a compilation warning when CONFIG_XEN is enabled.

arch/arm/include/asm/xen/page.h:80:0: warning: "virt_to_pfn" redefined [enabled by default]
 #define virt_to_pfn(v)          (PFN_DOWN(__pa(v)))
 ^
In file included from arch/arm/include/asm/page.h:163:0,
                 from arch/arm/include/asm/xen/page.h:4,
                 from include/xen/page.h:4,
                 from arch/arm/xen/grant-table.c:33:

The definition in memory.h is nearly the same (it directly expand PFN_DOWN),
so we can safely drop virt_to_pfn in xen include.

Signed-off-by: Julien Grall <julien.grall@linaro.org>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2014-04-24 14:04:57 +01:00
Ian Campbell
5e40704ed2 arm: xen: implement multicall hypercall support.
As part of this make the usual change to xen_ulong_t in place of unsigned long.
This change has no impact on x86.

The Linux definition of struct multicall_entry.result differs from the Xen
definition, I think for good reasons, and used a long rather than an unsigned
long. Therefore introduce a xen_long_t, which is a long on x86 architectures
and a signed 64-bit integer on ARM.

Use uint32_t nr_calls on x86 for consistency with the ARM definition.

Build tested on amd64 and i386 builds. Runtime tested on ARM.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2014-04-24 13:09:46 +01:00
Zoltan Kiss
1429d46df4 xen/grant-table: Refactor gnttab_[un]map_refs to avoid m2p_override
The grant mapping API does m2p_override unnecessarily: only gntdev needs it,
for blkback and future netback patches it just cause a lock contention, as
those pages never go to userspace. Therefore this series does the following:
- the bulk of the original function (everything after the mapping hypercall)
  is moved to arch-dependent set/clear_foreign_p2m_mapping
- the "if (xen_feature(XENFEAT_auto_translated_physmap))" branch goes to ARM
- therefore the ARM function could be much smaller, the m2p_override stubs
  could be also removed
- on x86 the set_phys_to_machine calls were moved up to this new funcion
  from m2p_override functions
- and m2p_override functions are only called when there is a kmap_ops param

It also removes a stray space from arch/x86/include/asm/xen/page.h.

Signed-off-by: Zoltan Kiss <zoltan.kiss@citrix.com>
Suggested-by: Anthony Liguori <aliguori@amazon.com>
Suggested-by: David Vrabel <david.vrabel@citrix.com>
Suggested-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
2014-03-18 14:40:19 +00:00
Linus Torvalds
84621c9b18 Features:
- FIFO event channels. Key advantages: support for over 100,000 events (2^17),
    16 different event priorities, improved fairness in event latency through
    the use of FIFOs.
  - Xen PVH support. "It’s a fully PV kernel mode, running with paravirtualized
    disk and network, paravirtualized interrupts and timers, no emulated devices
    of any kind (and thus no qemu), no BIOS or legacy boot — but instead of
    requiring PV MMU, it uses the HVM hardware extensions to virtualize the
    pagetables, as well as system calls and other privileged operations."
    (from "The Paravirtualization Spectrum, Part 2: From poles to a spectrum")
 Bug-fixes:
  - Fixes in balloon driver (refactor and make it work under ARM)
  - Allow xenfb to be used in HVM guests.
  - Allow xen_platform_pci=0 to work properly.
  - Refactors in event channels.
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Merge tag 'stable/for-linus-3.14-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull Xen updates from Konrad Rzeszutek Wilk:
 "Two major features that Xen community is excited about:

  The first is event channel scalability by David Vrabel - we switch
  over from an two-level per-cpu bitmap of events (IRQs) - to an FIFO
  queue with priorities.  This lets us be able to handle more events,
  have lower latency, and better scalability.  Good stuff.

  The other is PVH by Mukesh Rathor.  In short, PV is a mode where the
  kernel lets the hypervisor program page-tables, segments, etc.  With
  EPT/NPT capabilities in current processors, the overhead of doing this
  in an HVM (Hardware Virtual Machine) container is much lower than the
  hypervisor doing it for us.

  In short we let a PV guest run without doing page-table, segment,
  syscall, etc updates through the hypervisor - instead it is all done
  within the guest container.  It is a "hybrid" PV - hence the 'PVH'
  name - a PV guest within an HVM container.

  The major benefits are less code to deal with - for example we only
  use one function from the the pv_mmu_ops (which has 39 function
  calls); faster performance for syscall (no context switches into the
  hypervisor); less traps on various operations; etc.

  It is still being baked - the ABI is not yet set in stone.  But it is
  pretty awesome and we are excited about it.

  Lastly, there are some changes to ARM code - you should get a simple
  conflict which has been resolved in #linux-next.

  In short, this pull has awesome features.

  Features:
   - FIFO event channels.  Key advantages: support for over 100,000
     events (2^17), 16 different event priorities, improved fairness in
     event latency through the use of FIFOs.
   - Xen PVH support.  "It’s a fully PV kernel mode, running with
     paravirtualized disk and network, paravirtualized interrupts and
     timers, no emulated devices of any kind (and thus no qemu), no BIOS
     or legacy boot — but instead of requiring PV MMU, it uses the HVM
     hardware extensions to virtualize the pagetables, as well as system
     calls and other privileged operations." (from "The
     Paravirtualization Spectrum, Part 2: From poles to a spectrum")

  Bug-fixes:
   - Fixes in balloon driver (refactor and make it work under ARM)
   - Allow xenfb to be used in HVM guests.
   - Allow xen_platform_pci=0 to work properly.
   - Refactors in event channels"

* tag 'stable/for-linus-3.14-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: (52 commits)
  xen/pvh: Set X86_CR0_WP and others in CR0 (v2)
  MAINTAINERS: add git repository for Xen
  xen/pvh: Use 'depend' instead of 'select'.
  xen: delete new instances of __cpuinit usage
  xen/fb: allow xenfb initialization for hvm guests
  xen/evtchn_fifo: fix error return code in evtchn_fifo_setup()
  xen-platform: fix error return code in platform_pci_init()
  xen/pvh: remove duplicated include from enlighten.c
  xen/pvh: Fix compile issues with xen_pvh_domain()
  xen: Use dev_is_pci() to check whether it is pci device
  xen/grant-table: Force to use v1 of grants.
  xen/pvh: Support ParaVirtualized Hardware extensions (v3).
  xen/pvh: Piggyback on PVHVM XenBus.
  xen/pvh: Piggyback on PVHVM for grant driver (v4)
  xen/grant: Implement an grant frame array struct (v3).
  xen/grant-table: Refactor gnttab_init
  xen/grants: Remove gnttab_max_grant_frames dependency on gnttab_init.
  xen/pvh: Piggyback on PVHVM for event channels (v2)
  xen/pvh: Update E820 to work with PVH (v2)
  xen/pvh: Secondary VCPU bringup (non-bootup CPUs)
  ...
2014-01-22 22:00:18 -08:00
Konrad Rzeszutek Wilk
efaf30a335 xen/grant: Implement an grant frame array struct (v3).
The 'xen_hvm_resume_frames' used to be an 'unsigned long'
and contain the virtual address of the grants. That was OK
for most architectures (PVHVM, ARM) were the grants are contiguous
in memory. That however is not the case for PVH - in which case
we will have to do a lookup for each virtual address for the PFN.

Instead of doing that, lets make it a structure which will contain
the array of PFNs, the virtual address and the count of said PFNs.

Also provide a generic functions: gnttab_setup_auto_xlat_frames and
gnttab_free_auto_xlat_frames to populate said structure with
appropriate values for PVHVM and ARM.

To round it off, change the name from 'xen_hvm_resume_frames' to
a more descriptive one - 'xen_auto_xlat_grant_frames'.

For PVH, in patch "xen/pvh: Piggyback on PVHVM for grant driver"
we will populate the 'xen_auto_xlat_grant_frames' by ourselves.

v2 moves the xen_remap in the gnttab_setup_auto_xlat_frames
and also introduces xen_unmap for gnttab_free_auto_xlat_frames.

Suggested-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
[v3: Based on top of 'asm/xen/page.h: remove redundant semicolon']
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
2014-01-06 10:44:20 -05:00
Wei Liu
02bcf053e9 asm/xen/page.h: remove redundant semicolon
Signed-off-by: Wei Liu <liuw@liuw.name>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
2014-01-06 10:07:27 -05:00
Rob Herring
0a5ccc8650 ARM: 7933/1: rename ioremap_cached to ioremap_cache
ioremap_cache is more aligned with other architectures.
There are only 2 users of this in the kernel: pxa2xx-flash and Xen.

This fixes Xen build failures on arm64:

drivers/tty/hvc/hvc_xen.c:233:2: error: implicit declaration of function 'ioremap_cached' [-Werror=implicit-function-declaration]
drivers/xen/grant-table.c:1174:3: error: implicit declaration of function 'ioremap_cached' [-Werror=implicit-function-declaration]
drivers/xen/xenbus/xenbus_probe.c:778:4: error: implicit declaration of function 'ioremap_cached' [-Werror=implicit-function-declaration]

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-01-05 14:00:01 +00:00
Stefano Stabellini
18c51e1a3f xen/arm: pfn_to_mfn and mfn_to_pfn return the argument if nothing is in the p2m
Some common Xen drivers, like balloon.c, call pfn_to_mfn and mfn_to_pfn
even for autotranslate guests, expecting the argument back.
The following commit broke these drivers by changing the behavior of
pfn_to_mfn and mfn_to_pfn:

commit 4a19138c65
Author: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Date:   Thu Oct 17 16:22:27 2013 +0000

    arm/xen,arm64/xen: introduce p2m

They now return INVALID_P2M_ENTRY if Linux doesn't actually know what is
the mfn backing a pfn or what is the pfn corresponding to an mfn.
Fix the regression by switching to the old behavior.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Tested-by: Ian Campbell <ian.campbell@citrix.com>
2013-11-11 12:48:58 -05:00
Konrad Rzeszutek Wilk
e1d8f62ad4 Merge remote-tracking branch 'stefano/swiotlb-xen-9.1' into stable/for-linus-3.13
* stefano/swiotlb-xen-9.1:
  swiotlb-xen: fix error code returned by xen_swiotlb_map_sg_attrs
  swiotlb-xen: static inline xen_phys_to_bus, xen_bus_to_phys, xen_virt_to_bus and range_straddles_page_boundary
  grant-table: call set_phys_to_machine after mapping grant refs
  arm,arm64: do not always merge biovec if we are running on Xen
  swiotlb: print a warning when the swiotlb is full
  swiotlb-xen: use xen_dma_map/unmap_page, xen_dma_sync_single_for_cpu/device
  xen: introduce xen_dma_map/unmap_page and xen_dma_sync_single_for_cpu/device
  swiotlb-xen: use xen_alloc/free_coherent_pages
  xen: introduce xen_alloc/free_coherent_pages
  arm64/xen: get_dma_ops: return xen_dma_ops if we are running as xen_initial_domain
  arm/xen: get_dma_ops: return xen_dma_ops if we are running as xen_initial_domain
  swiotlb-xen: introduce xen_swiotlb_set_dma_mask
  xen/arm,arm64: enable SWIOTLB_XEN
  xen: make xen_create_contiguous_region return the dma address
  xen/x86: allow __set_phys_to_machine for autotranslate guests
  arm/xen,arm64/xen: introduce p2m
  arm64: define DMA_ERROR_CODE
  arm: make SWIOTLB available

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

Conflicts:
	arch/arm/include/asm/dma-mapping.h
	drivers/xen/swiotlb-xen.c

[Conflicts arose b/c "arm: make SWIOTLB available" v8 was in Stefano's
branch, while I had v9 + Ack from Russel. I also fixed up white-space
issues]
2013-11-08 16:10:48 -05:00
Stefano Stabellini
7100b077ab xen: introduce xen_dma_map/unmap_page and xen_dma_sync_single_for_cpu/device
Introduce xen_dma_map_page, xen_dma_unmap_page,
xen_dma_sync_single_for_cpu and xen_dma_sync_single_for_device.
They have empty implementations on x86 and ia64 but they call the
corresponding platform dma_ops function on arm and arm64.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>

Changes in v9:
- xen_dma_map_page return void, avoid page_to_phys.
2013-10-25 10:39:49 +00:00
Stefano Stabellini
d6fe76c58c xen: introduce xen_alloc/free_coherent_pages
xen_swiotlb_alloc_coherent needs to allocate a coherent buffer for cpu
and devices. On native x86 is sufficient to call __get_free_pages in
order to get a coherent buffer, while on ARM (and potentially ARM64) we
need to call the native dma_ops->alloc implementation.

Introduce xen_alloc_coherent_pages to abstract the arch specific buffer
allocation.

Similarly introduce xen_free_coherent_pages to free a coherent buffer:
on x86 is simply a call to free_pages while on ARM and ARM64 is
arm_dma_ops.free.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>


Changes in v7:
- rename __get_dma_ops to __generic_dma_ops;
- call __generic_dma_ops(hwdev)->alloc/free on arm64 too.

Changes in v6:
- call __get_dma_ops to get the native dma_ops pointer on arm.
2013-10-09 17:18:14 +00:00
Stefano Stabellini
83862ccfc0 xen/arm,arm64: enable SWIOTLB_XEN
Xen on arm and arm64 needs SWIOTLB_XEN: when running on Xen we need to
program the hardware with mfns rather than pfns for dma addresses.
Remove SWIOTLB_XEN dependency on X86 and PCI and make XEN select
SWIOTLB_XEN on arm and arm64.

At the moment always rely on swiotlb-xen, but when Xen starts supporting
hardware IOMMUs we'll be able to avoid it conditionally on the presence
of an IOMMU on the platform.

Implement xen_create_contiguous_region on arm and arm64: for the moment
we assume that dom0 has been mapped 1:1 (physical addresses == machine
addresses) therefore we don't need to call XENMEM_exchange. Simply
return the physical address as dma address.

Initialize the xen-swiotlb from xen_early_init (before the native
dma_ops are initialized), set xen_dma_ops to &xen_swiotlb_dma_ops.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>


Changes in v8:
- assume dom0 is mapped 1:1, no need to call XENMEM_exchange.

Changes in v7:
- call __set_phys_to_machine_multi from xen_create_contiguous_region and
xen_destroy_contiguous_region to update the P2M;
- don't call XENMEM_unpin, it has been removed;
- call XENMEM_exchange instead of XENMEM_exchange_and_pin;
- set nr_exchanged to 0 before calling the hypercall.

Changes in v6:
- introduce and export xen_dma_ops;
- call xen_mm_init from as arch_initcall.

Changes in v4:
- remove redefinition of DMA_ERROR_CODE;
- update the code to use XENMEM_exchange_and_pin and XENMEM_unpin;
- add a note about hardware IOMMU in the commit message.

Changes in v3:
- code style changes;
- warn on XENMEM_put_dma_buf failures.
2013-10-10 13:40:44 +00:00
Stefano Stabellini
4a19138c65 arm/xen,arm64/xen: introduce p2m
Introduce physical to machine and machine to physical tracking
mechanisms based on rbtrees for arm/xen and arm64/xen.

We need it because any guests on ARM are an autotranslate guests,
therefore a physical address is potentially different from a machine
address. When programming a device to do DMA, we need to be
extra-careful to use machine addresses rather than physical addresses to
program the device. Therefore we need to know the physical to machine
mappings.

For the moment we assume that dom0 starts with a 1:1 physical to machine
mapping, in other words physical addresses correspond to machine
addresses. However when mapping a foreign grant reference, obviously the
1:1 model doesn't work anymore. So at the very least we need to be able
to track grant mappings.

We need locking to protect accesses to the two trees.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>

Changes in v8:
- move pfn_to_mfn and mfn_to_pfn to page.h as static inline functions;
- no need to walk the tree if phys_to_mach.rb_node is NULL;
- correctly handle multipage p2m entries;
- substitute the spin_lock with a rwlock.
2013-10-17 16:22:27 +00:00
Stefano Stabellini
176455e9a9 xen/arm and xen/arm64: implement HYPERVISOR_tmem_op
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
2013-07-04 11:41:12 +00:00
Stefano Stabellini
f0a8d59791 arm/xen: define xen_remap as ioremap_cached
Define xen_remap as ioremap_cache (MT_MEMORY and MT_DEVICE_CACHED end up
having the same AttrIndx encoding).

Remove include asm/mach/map.h, not unneeded.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
2013-06-04 16:32:15 +00:00
Stefano Stabellini
ea0af61321 xen/arm: implement HYPERVISOR_vcpu_op
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Ian Campbell <ian.campbell@citrix.com>
2013-04-25 16:46:07 +00:00
Ian Campbell
85323a991d xen: arm: mandate EABI and use generic atomic operations.
Rob Herring has observed that c81611c4e9 "xen: event channel arrays are
xen_ulong_t and not unsigned long" introduced a compile failure when building
without CONFIG_AEABI:

/tmp/ccJaIZOW.s: Assembler messages:
/tmp/ccJaIZOW.s:831: Error: even register required -- `ldrexd r5,r6,[r4]'

Will Deacon pointed out that this is because OABI does not require even base
registers for 64-bit values. We can avoid this by simply using the existing
atomic64_xchg operation and the same containerof trick as used by the cmpxchg
macros. However since this code is used on memory which is shared with the
hypervisor we require proper atomic instructions and cannot use the generic
atomic64 callbacks (which are based on spinlocks), therefore add a dependency
on !GENERIC_ATOMIC64. Since we already depend on !CPU_V6 there isn't much
downside to this.

While thinking about this we also observed that OABI has different struct
alignment requirements to EABI, which is a problem for hypercall argument
structs which are shared with the hypervisor and which must be in EABI layout.
Since I don't expect people to want to run OABI kernels on Xen depend on
CONFIG_AEABI explicitly too (although it also happens to be enforced by the
!GENERIC_ATOMIC64 requirement too).

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Rob Herring <robherring2@gmail.com>
Acked-by: Stefano Stabellini <Stefano.Stabellini@eu.citrix.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-03-11 13:52:19 -04:00
Ian Campbell
c81611c4e9 xen: event channel arrays are xen_ulong_t and not unsigned long
On ARM we want these to be the same size on 32- and 64-bit.

This is an ABI change on ARM. X86 does not change.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Cc: Jan Beulich <JBeulich@suse.com>
Cc: Keir (Xen.org) <keir@xen.org>
Cc: Tim Deegan <tim@xen.org>
Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: xen-devel@lists.xen.org
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-02-20 08:45:07 -05:00