powerpc/iommu: Incorrect DDW Table is referenced for SR-IOV device

For an SR-IOV device, while enabling DDW, a new table is created and
added at index 1 in the group. In the below 2 scenarios, the t

powerpc/iommu: Incorrect DDW Table is referenced for SR-IOV device

For an SR-IOV device, while enabling DDW, a new table is created and
added at index 1 in the group. In the below 2 scenarios, the table is
incorrectly referenced at index 0 (which is where the table is for
default DMA window).

1. When adding DDW

This issue is exposed with "slub_debug". Error thrown out from
dma_iommu_dma_supported()

Warning: IOMMU offset too big for device mask
mask: 0xffffffff, table offset: 0x800000000000000

2. During Dynamic removal of the PCI device.

Error is from iommu_tce_table_put() since a NULL table pointer is
passed in.

Fixes: 381ceda88c4c ("powerpc/pseries/iommu: Make use of DDW for indirect mapping")
Cc: stable@vger.kernel.org # v5.15+
Signed-off-by: Gaurav Batra <gbatra@linux.vnet.ibm.com>
Reviewed-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230505184701.91613-1-gbatra@linux.vnet.ibm.com

show more ...

powerpc/iommu: Report the correct most efficient DMA mask for PCI devices

According to dma-api.rst, the dma_get_required_mask() helper should return
"the mask that the platform requires to operate e

powerpc/iommu: Report the correct most efficient DMA mask for PCI devices

According to dma-api.rst, the dma_get_required_mask() helper should return
"the mask that the platform requires to operate efficiently". Which in
the case of PPC64 means the bypass mask and not a mask from an IOMMU table
which is shorter and slower to use due to map/unmap operations (especially
expensive on "pseries").

However the existing implementation ignores the possibility of bypassing
and returns the IOMMU table mask on the pseries platform which makes some
drivers (mpt3sas is one example) choose 32bit DMA even though bypass is
supported. The powernv platform sort of handles it by having a bigger
default window with a mask >=40 but it only works as drivers choose
63/64bit if the required mask is >32 which is rather pointless.

This reintroduces the bypass capability check to let drivers make
a better choice of the DMA mask.

Fixes: f1565c24b596 ("powerpc: use the generic dma_ops_bypass mode")
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210930034454.95794-1-aik@ozlabs.ru

show more ...

powerpc/dma: Fallback to dma_ops when persistent memory present

So far we have been using huge DMA windows to map all the RAM available.
The RAM is normally mapped to the VM address space contiguous

powerpc/dma: Fallback to dma_ops when persistent memory present

So far we have been using huge DMA windows to map all the RAM available.
The RAM is normally mapped to the VM address space contiguously, and
there is always a reasonable upper limit for possible future hot plugged
RAM which makes it easy to map all RAM via IOMMU.

Now there is persistent memory ("ibm,pmemory" in the FDT) which (unlike
normal RAM) can map anywhere in the VM space beyond the maximum RAM size
and since it can be used for DMA, it requires extending the huge window
up to MAX_PHYSMEM_BITS which requires hypervisor support for:
1. huge TCE tables;
2. multilevel TCE tables;
3. huge IOMMU pages.

Certain hypervisors cannot do either so the only option left is
restricting the huge DMA window to include only RAM and fallback to
the default DMA window for persistent memory.

This defines arch_dma_map_direct/etc to allow generic DMA code perform
additional checks on whether direct DMA is still possible.

This checks if the system has persistent memory. If it does not,
the DMA bypass mode is selected, i.e.
* dev->bus_dma_limit = 0
* dev->dma_ops_bypass = true <- this avoid calling dma_ops for mapping.

If there is such memory, this creates identity mapping only for RAM and
sets the dev->bus_dma_limit to let the generic code decide whether to
call into the direct DMA or the indirect DMA ops.

This should not change the existing behaviour when no persistent memory
as dev->dma_ops_bypass is expected to be set.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Christoph Hellwig <hch@lst.de>

show more ...

dma-mapping: add a new dma_alloc_pages API

This API is the equivalent of alloc_pages, except that the returned memory
is guaranteed to be DMA addressable by the passed in device. The
implementation

dma-mapping: add a new dma_alloc_pages API

This API is the equivalent of alloc_pages, except that the returned memory
is guaranteed to be DMA addressable by the passed in device. The
implementation will also be used to provide a more sensible replacement
for DMA_ATTR_NON_CONSISTENT flag.

Additionally dma_alloc_noncoherent is switched over to use dma_alloc_pages
as its backend.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de> (MIPS part)

show more ...

powerpc/dma: Fix dma_map_ops::get_required_mask

There are 2 problems with it:
1. "<" vs expected "<<"
2. the shift number is an IOMMU page number mask, not an address
mask as the IOMMU page sh

powerpc/dma: Fix dma_map_ops::get_required_mask

There are 2 problems with it:
1. "<" vs expected "<<"
2. the shift number is an IOMMU page number mask, not an address
mask as the IOMMU page shift is missing.

This did not hit us before f1565c24b596 ("powerpc: use the generic
dma_ops_bypass mode") because we had additional code to handle bypass
mask so this chunk (almost?) never executed.However there were
reports that aacraid does not work with "iommu=nobypass".

After f1565c24b596, aacraid (and probably others which call
dma_get_required_mask() before setting the mask) was unable to enable
64bit DMA and fall back to using IOMMU which was known not to work,
one of the problems is double free of an IOMMU page.

This fixes DMA for aacraid, both with and without "iommu=nobypass" in
the kernel command line. Verified with "stress-ng -d 4".

Fixes: 6a5c7be5e484 ("powerpc: Override dma_get_required_mask by platform hook and ops")
Cc: stable@vger.kernel.org # v3.2+
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200908015106.79661-1-aik@ozlabs.ru

show more ...

powerpc: use the generic dma_ops_bypass mode

Use the DMA API bypass mechanism for direct window mappings. This uses
common code and speed up the direct mapping case by avoiding indirect
calls just

powerpc: use the generic dma_ops_bypass mode

Use the DMA API bypass mechanism for direct window mappings. This uses
common code and speed up the direct mapping case by avoiding indirect
calls just when not using dma ops at all. It also fixes a problem where
the sync_* methods were using the bypass check for DMA allocations, but
those are part of the streaming ops.

Note that this patch loses the DMA_ATTR_WEAK_ORDERING override, which
has never been well defined, as is only used by a few drivers, which
IIRC never showed up in the typical Cell blade setups that are affected
by the ordering workaround.

Fixes: efd176a04bef ("powerpc/pseries/dma: Allow SWIOTLB")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>

show more ...

dma-mapping: explicitly wire up ->mmap and ->get_sgtable

While the default ->mmap and ->get_sgtable implementations work for the
majority of our dma_map_ops impementations they are inherently safe
f

dma-mapping: explicitly wire up ->mmap and ->get_sgtable

While the default ->mmap and ->get_sgtable implementations work for the
majority of our dma_map_ops impementations they are inherently safe
for others that don't use the page allocator or CMA and/or use their
own way of remapping not covered by the common code. So remove the
defaults if these methods are not wired up, but instead wire up the
default implementations for all safe instances.

Fixes: e1c7e324539a ("dma-mapping: always provide the dma_map_ops based implementation")
Signed-off-by: Christoph Hellwig <hch@lst.de>

show more ...

powerpc/iommu: Allow bypass-only for DMA

POWER8 and newer support a bypass mode which maps all host memory to
PCI buses so an IOMMU table is not always required. However if we fail to
create such a

powerpc/iommu: Allow bypass-only for DMA

POWER8 and newer support a bypass mode which maps all host memory to
PCI buses so an IOMMU table is not always required. However if we fail to
create such a table, the DMA setup fails and the kernel does not boot.

This skips the 32bit DMA setup check if the bypass is selected.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190718051139.74787-3-aik@ozlabs.ru

show more ...

powerpc/pseries/dma: Allow SWIOTLB

The commit 8617a5c5bc00 ("powerpc/dma: handle iommu bypass in
dma_iommu_ops") merged direct DMA ops into the IOMMU DMA ops allowing
SWIOTLB as well but only for ma

powerpc/pseries/dma: Allow SWIOTLB

The commit 8617a5c5bc00 ("powerpc/dma: handle iommu bypass in
dma_iommu_ops") merged direct DMA ops into the IOMMU DMA ops allowing
SWIOTLB as well but only for mapping; the unmapping and bouncing parts
were left unmodified.

This adds missing direct unmapping calls to .unmap_page() and
.unmap_sg().

This adds missing sync callbacks and directs them to the direct DMA
hooks.

Fixes: 8617a5c5bc00 ("powerpc/dma: handle iommu bypass in dma_iommu_ops")
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

show more ...

powerpc: remove device_to_mask()

Use the dma_get_mask() helper from dma-mapping.h instead, as they are
functionally identical.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alexey Kard

powerpc: remove device_to_mask()

Use the dma_get_mask() helper from dma-mapping.h instead, as they are
functionally identical.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

show more ...

powerpc/dma: use the dma_direct mapping routines

Switch the streaming DMA mapping and ownership transfer methods to the
functionally identical dma_direct_ versions. Factor the cache
maintainance he

powerpc/dma: use the dma_direct mapping routines

Switch the streaming DMA mapping and ownership transfer methods to the
functionally identical dma_direct_ versions. Factor the cache
maintainance helpers into the form expected by the common code for that.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Christian Zigotzky <chzigotzky@xenosoft.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

show more ...

powerpc/dma: use the dma-direct allocator for coherent platforms

The generic code allows a few nice things such as node local allocations
and dipping into the CMA area. The lookup of the right zone

powerpc/dma: use the dma-direct allocator for coherent platforms

The generic code allows a few nice things such as node local allocations
and dipping into the CMA area. The lookup of the right zone for a given
dma mask works a little different, but the results should be the same.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Christian Zigotzky <chzigotzky@xenosoft.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

show more ...

powerpc/dma: remove dma_nommu_dma_supported

This function is largely identical to the generic version used
everywhere else. Replace it with the generic version.

Signed-off-by: Christoph Hellwig <h

powerpc/dma: remove dma_nommu_dma_supported

This function is largely identical to the generic version used
everywhere else. Replace it with the generic version.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Christian Zigotzky <chzigotzky@xenosoft.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

show more ...

powerpc/dma: remove dma_nommu_get_required_mask

This function is identical to the generic dma_direct_get_required_mask,
except that the generic version also takes the bus_dma_mask account,
which cou

powerpc/dma: remove dma_nommu_get_required_mask

This function is identical to the generic dma_direct_get_required_mask,
except that the generic version also takes the bus_dma_mask account,
which could lead to incorrect results in the powerpc version.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Christian Zigotzky <chzigotzky@xenosoft.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

show more ...

powerpc/dma: remove dma_nommu_mmap_coherent

The coherent cache version of this function already is functionally
identicall to the default version, and by defining the
arch_dma_coherent_to_pfn hook t

powerpc/dma: remove dma_nommu_mmap_coherent

The coherent cache version of this function already is functionally
identicall to the default version, and by defining the
arch_dma_coherent_to_pfn hook the same is ture for the noncoherent
version as well.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Christian Zigotzky <chzigotzky@xenosoft.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

show more ...

powerpc/cell: use the generic iommu bypass code

This gets rid of a lot of clumsy code and finally allows us to mark
dma_iommu_ops const.

Includes fixes from Michael Ellerman.

Signed-off-by: Christ

powerpc/cell: use the generic iommu bypass code

This gets rid of a lot of clumsy code and finally allows us to mark
dma_iommu_ops const.

Includes fixes from Michael Ellerman.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

show more ...

powerpc/dma: handle iommu bypass in dma_iommu_ops

Add a new iommu_bypass flag to struct dev_archdata so that the dma_iommu
implementation can handle the direct mapping transparently instead of
switi

powerpc/dma: handle iommu bypass in dma_iommu_ops

Add a new iommu_bypass flag to struct dev_archdata so that the dma_iommu
implementation can handle the direct mapping transparently instead of
switiching ops around. Setting of this flag is controlled by new
pci_controller_ops method.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Christian Zigotzky <chzigotzky@xenosoft.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

show more ...

powerpc/dma: untangle vio_dma_mapping_ops from dma_iommu_ops

vio_dma_mapping_ops currently does a lot of indirect calls through
dma_iommu_ops, which not only make the code harder to follow but are
a

powerpc/dma: untangle vio_dma_mapping_ops from dma_iommu_ops

vio_dma_mapping_ops currently does a lot of indirect calls through
dma_iommu_ops, which not only make the code harder to follow but are
also expensive in the post-spectre world. Unwind the indirect calls
by calling the ppc_iommu_* or iommu_* APIs directly applicable, or
just use the dma_iommu_* methods directly where we can.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

show more ...

powerpc/dma: remove the unused dma_iommu_ops export

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc/iommu: remove the mapping_error dma_map_ops method

The powerpc iommu code already returns (~(dma_addr_t)0x0) on mapping
failures, so we can switch over to returning DMA_MAPPING_ERROR and let

powerpc/iommu: remove the mapping_error dma_map_ops method

The powerpc iommu code already returns (~(dma_addr_t)0x0) on mapping
failures, so we can switch over to returning DMA_MAPPING_ERROR and let
the core dma-mapping code handle the rest.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>

show more ...

powerpc: rename dma_direct_ to dma_nommu_

We want to use the dma_direct_ namespace for a generic implementation,
so rename powerpc to the second best choice: dma_nommu_.

Signed-off-by: Christoph He

powerpc: rename dma_direct_ to dma_nommu_

We want to use the dma_direct_ namespace for a generic implementation,
so rename powerpc to the second best choice: dma_nommu_.

Signed-off-by: Christoph Hellwig <hch@lst.de>

show more ...

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

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>

show more ...

powerpc: implement ->mapping_error

DMA_ERROR_CODE is going to go away, so don't rely on it. Instead
define a ->mapping_error method for all IOMMU based dma operation
instances. The direct ops don'

powerpc: implement ->mapping_error

DMA_ERROR_CODE is going to go away, so don't rely on it. Instead
define a ->mapping_error method for all IOMMU based dma operation
instances. The direct ops don't ever return an error and don't
need a ->mapping_error method.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>

show more ...

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 a

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>

show more ...

powerpc/iommu: Support "hybrid" iommu/direct DMA ops for coherent_mask < dma_mask

This patch adds the ability to the DMA direct ops to fallback to the IOMMU
ops for coherent alloc/free if the cohere

powerpc/iommu: Support "hybrid" iommu/direct DMA ops for coherent_mask < dma_mask

This patch adds the ability to the DMA direct ops to fallback to the IOMMU
ops for coherent alloc/free if the coherent mask of the device isn't
suitable for accessing the direct DMA space and the device also happens
to have an active IOMMU table.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

show more ...