Commit Graph

60 Commits

Author SHA1 Message Date
Christoph Hellwig
1fa0682448 dma-mapping: remove dma_release_declared_memory
This function is entirely unused given that declared memory is
generally provided by platform setup code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-09-04 11:13:19 +02:00
Yoshihiro Shimoda
6ba99411b8 dma-mapping: introduce dma_get_merge_boundary()
This patch adds a new DMA API "dma_get_merge_boundary". This function
returns the DMA merge boundary if the DMA layer can merge the segments.
This patch also adds the implementation for a new dma_map_ops pointer.

Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-09-03 08:33:01 +02:00
Yoshihiro Shimoda
99d2b93867 Documentation: DMA-API: fix a function name of max_mapping_size
The exported function name is dma_max_mapping_size(), not
dma_direct_max_mapping_size() so that this patch fixes
the function name in the documentation.

Fixes: 133d624b1c ("dma: Introduce dma_max_mapping_size()")
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-06-07 11:10:33 -06:00
Linus Torvalds
45ba8d5d06 virtio: fixes, cleanups
Several fixes, most notably fix for virtio on swiotlb systems.
 
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

Pull virtio updates from Michael Tsirkin:
 "Several fixes, most notably fix for virtio on swiotlb systems"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  vhost: silence an unused-variable warning
  virtio: hint if callbacks surprisingly might sleep
  virtio-ccw: wire up ->bus_name callback
  s390/virtio: handle find on invalid queue gracefully
  virtio-ccw: diag 500 may return a negative cookie
  virtio_balloon: remove the unnecessary 0-initialization
  virtio-balloon: improve update_balloon_size_func
  virtio-blk: Consider virtio_max_dma_size() for maximum segment size
  virtio: Introduce virtio_max_dma_size()
  dma: Introduce dma_max_mapping_size()
  swiotlb: Add is_swiotlb_active() function
  swiotlb: Introduce swiotlb_max_mapping_size()
2019-03-10 12:47:57 -07:00
Linus Torvalds
b7a7d1c1ec DMA mapping updates for 5.1
- add debugfs support for dumping dma-debug information (Corentin Labbe)
  - Kconfig cleanups (Andy Shevchenko and me)
  - debugfs cleanups (Greg Kroah-Hartman)
  - improve dma_map_resource and use it in the media code
  - arch_setup_dma_ops / arch_teardown_dma_ops cleanups
  - various small cleanups and improvements for the per-device coherent
    allocator
  - make the DMA mask an upper bound and don't fail "too large" dma mask
    in the remaning two architectures - this will allow big driver
    cleanups in the following merge windows
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Merge tag 'dma-mapping-5.1' of git://git.infradead.org/users/hch/dma-mapping

Pull DMA mapping updates from Christoph Hellwig:

 - add debugfs support for dumping dma-debug information (Corentin
   Labbe)

 - Kconfig cleanups (Andy Shevchenko and me)

 - debugfs cleanups (Greg Kroah-Hartman)

 - improve dma_map_resource and use it in the media code

 - arch_setup_dma_ops / arch_teardown_dma_ops cleanups

 - various small cleanups and improvements for the per-device coherent
   allocator

 - make the DMA mask an upper bound and don't fail "too large" dma mask
   in the remaning two architectures - this will allow big driver
   cleanups in the following merge windows

* tag 'dma-mapping-5.1' of git://git.infradead.org/users/hch/dma-mapping: (21 commits)
  Documentation/DMA-API-HOWTO: update dma_mask sections
  sparc64/pci_sun4v: allow large DMA masks
  sparc64/iommu: allow large DMA masks
  sparc64: refactor the ali DMA quirk
  ccio: allow large DMA masks
  dma-mapping: remove the DMA_MEMORY_EXCLUSIVE flag
  dma-mapping: remove dma_mark_declared_memory_occupied
  dma-mapping: move CONFIG_DMA_CMA to kernel/dma/Kconfig
  dma-mapping: improve selection of dma_declare_coherent availability
  dma-mapping: remove an incorrect __iommem annotation
  of: select OF_RESERVED_MEM automatically
  device.h: dma_mem is only needed for HAVE_GENERIC_DMA_COHERENT
  mfd/sm501: depend on HAS_DMA
  dma-mapping: add a kconfig symbol for arch_teardown_dma_ops availability
  dma-mapping: add a kconfig symbol for arch_setup_dma_ops availability
  dma-mapping: move debug configuration options to kernel/dma
  dma-debug: add dumping facility via debugfs
  dma: debug: no need to check return value of debugfs_create functions
  videobuf2: replace a layering violation with dma_map_resource
  dma-mapping: don't BUG when calling dma_map_resource on RAM
  ...
2019-03-10 11:54:48 -07:00
Joerg Roedel
133d624b1c dma: Introduce dma_max_mapping_size()
The function returns the maximum size that can be mapped
using DMA-API functions. The patch also adds the
implementation for direct DMA and a new dma_map_ops pointer
so that other implementations can expose their limit.

Cc: stable@vger.kernel.org
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-03-06 11:19:11 -05:00
Christoph Hellwig
82c5de0ab8 dma-mapping: remove the DMA_MEMORY_EXCLUSIVE flag
All users of dma_declare_coherent want their allocations to be
exclusive, so default to exclusive allocations.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-20 07:27:00 -07:00
Christoph Hellwig
91a6fda95c dma-mapping: remove dma_mark_declared_memory_occupied
This API is not used anywhere, so remove it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-02-20 07:27:00 -07:00
Corentin Labbe
0a3b192c26 dma-debug: add dumping facility via debugfs
While debugging a DMA mapping leak, I needed to access
debug_dma_dump_mappings() but easily from user space.

This patch adds a /sys/kernel/debug/dma-api/dump file which contain all
current DMA mapping.

Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-02-01 10:06:44 +01:00
Corentin Labbe
31f4333070 Documentation: DMA-API: fix two typos
This patch fixes two typos, a missing "e" and dma-api/driver_filter was
incorrectly typed dma-api/driver-filter.

Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
[jc: fixed obvious language typos on the way in]
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-01-20 19:17:10 -07:00
Christoph Hellwig
06d4dd2f2c dma-mapping: deprecate dma_zalloc_coherent
We now always return zeroed memory from dma_alloc_coherent.  Note that
simply passing GFP_ZERO to dma_alloc_coherent wasn't always doing the
right thing to start with given that various allocators are not backed
by the page allocator and thus would ignore GFP_ZERO.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-12-20 08:14:09 +01:00
Robin Murphy
ad78dee0b6 dma-debug: Batch dma_debug_entry allocation
DMA debug entries are one of those things which aren't that useful
individually - we will always want some larger quantity of them - and
which we don't really need to manage the exact number of - we only care
about having 'enough'. In that regard, the current behaviour of creating
them one-by-one leads to a lot of unwarranted function call overhead and
memory wasted on alignment padding.

Now that we don't have to worry about freeing anything via
dma_debug_resize_entries(), we can optimise the allocation behaviour by
grabbing whole pages at once, which will save considerably on the
aforementioned overheads, and probably offer a little more cache/TLB
locality benefit for traversing the lists under normal operation. This
should also give even less reason for an architecture-level override of
the preallocation size, so make the definition unconditional - if there
is still any desire to change the compile-time value for some platforms
it would be better off as a Kconfig option anyway.

Since freeing a whole page of entries at once becomes enough of a
challenge that it's not really worth complicating dma_debug_init(), we
may as well tweak the preallocation behaviour such that as long as we
manage to allocate *some* pages, we can leave debugging enabled on a
best-effort basis rather than otherwise wasting them.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Tested-by: Qian Cai <cai@lca.pw>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-12-11 14:32:13 +01:00
Robin Murphy
ceb51173b2 dma-debug: Make leak-like behaviour apparent
Now that we can dynamically allocate DMA debug entries to cope with
drivers maintaining excessively large numbers of live mappings, a driver
which *does* actually have a bug leaking mappings (and is not unloaded)
will no longer trigger the "DMA-API: debugging out of memory - disabling"
message until it gets to actual kernel OOM conditions, which means it
could go unnoticed for a while. To that end, let's inform the user each
time the pool has grown to a multiple of its initial size, which should
make it apparent that they either have a leak or might want to increase
the preallocation size.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Tested-by: Qian Cai <cai@lca.pw>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-12-11 14:31:18 +01:00
Robin Murphy
2b9d9ac02b dma-debug: Dynamically expand the dma_debug_entry pool
Certain drivers such as large multi-queue network adapters can use pools
of mapped DMA buffers larger than the default dma_debug_entry pool of
65536 entries, with the result that merely probing such a device can
cause DMA debug to disable itself during boot unless explicitly given an
appropriate "dma_debug_entries=..." option.

Developers trying to debug some other driver on such a system may not be
immediately aware of this, and at worst it can hide bugs if they fail to
realise that dma-debug has already disabled itself unexpectedly by the
time their code of interest gets to run. Even once they do realise, it
can be a bit of a pain to emprirically determine a suitable number of
preallocated entries to configure, short of massively over-allocating.

There's really no need for such a static limit, though, since we can
quite easily expand the pool at runtime in those rare cases that the
preallocated entries are insufficient, which is arguably the least
surprising and most useful behaviour. To that end, refactor the
prealloc_memory() logic a little bit to generalise it for runtime
reallocations as well.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Tested-by: Qian Cai <cai@lca.pw>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-12-11 14:31:17 +01:00
Robin Murphy
9f191555ba dma-debug: Expose nr_total_entries in debugfs
Expose nr_total_entries in debugfs, so that {num,min}_free_entries
become even more meaningful to users interested in current/maximum
utilisation. This becomes even more relevant once nr_total_entries
may change at runtime beyond just the existing AMD GART debug code.

Suggested-by: John Garry <john.garry@huawei.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Tested-by: Qian Cai <cai@lca.pw>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-12-11 14:31:17 +01:00
Christoph Hellwig
2436bdcda5 dma-coherent: remove the DMA_MEMORY_MAP and DMA_MEMORY_IO flags
DMA_MEMORY_IO was never used in the tree, so remove it.  That means there is
no need for the DMA_MEMORY_MAP flag either now, so remove it as well and
change dma_declare_coherent_memory to return a normal errno value.

Signed-off-by: Christoph Hellwig <hch@lst.de>
 Reviewed-by: Marek Szyprowski <m.szyprowski@samsung.com>
2017-09-01 11:59:17 +02:00
Christoph Hellwig
b32dbc1e0b dma-coherent: remove the DMA_MEMORY_INCLUDES_CHILDREN flag
This flag was never implemented or used.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
2017-09-01 09:50:39 +02:00
Christoph Hellwig
2fd523c57e dma-mapping: remove dma_alloc_noncoherent and dma_free_noncoherent
No users left, everyone switched to the _attrs versions.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-08-29 10:04:02 +02:00
Mauro Carvalho Chehab
03158a70ad DMA-API.txt: standardize document format
Each text file under Documentation follows a different
format. Some doesn't even have titles!

Change its representation to follow the adopted standard,
using ReST markups for it to be parseable by Sphinx:

- Fix some title marks to match ReST;
- use :Author: for author name;
- foo_ is an hyperlink. Get rid of it;
- Mark literal blocks as such;
- Use tables on some places that are almost using the
  table format.

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2017-07-14 13:51:32 -06:00
Wolfram Sang
6a08d83e43 Documentation: DMA API: fix a typo in a function name
Correct the typo, the wrongly typed function does not exist.

Fixes: 6c9c6d6301 ("dma-debug: New interfaces to debug dma mapping errors")
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2017-06-05 15:57:02 -06:00
Niklas Söderlund
6f3d87968f dma-mapping: add dma_{map,unmap}_resource
Map/Unmap a device MMIO resource from a physical address. If no dma_map_ops
method is available the operation is a no-op.

Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2016-09-26 22:16:41 +05:30
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
Masahiro Yamada
000afe892e DMA-API: fix confusing sentence in Documentation/DMA-API.txt
Change the phrase "handed off to the driver" to "handed off to the
device" as in the paragraph below.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2016-01-11 18:29:00 -07:00
Christoph Hellwig
0e77acef8e dma: remove external references to dma_supported
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-09 15:11:24 -08:00
Sakari Ailus
7bc590b2fc Documentation: DMA API: Be more explicit that nents is always the same
The nents argument to the DMA API functions operating on scatterlists is
always the same. The documentation used different argument names and the
matter was not mentioned in Documentation/DMA-API-HOWTO.txt at all. Fix
these.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2015-09-24 15:50:06 -06:00
Sean O. Stalley
ad82362b2d mm: add dma_pool_zalloc() call to DMA API
Add a wrapper function for dma_pool_alloc() to get zeroed memory.

Signed-off-by: Sean O. Stalley <sean.stalley@intel.com>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Gilles Muller <Gilles.Muller@lip6.fr>
Cc: Nicolas Palix <nicolas.palix@imag.fr>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-08 15:35:28 -07:00
Yinghai Lu
3a9ad0b4fd PCI: Add pci_bus_addr_t
David Ahern reported that d63e2e1f3d ("sparc/PCI: Clip bridge windows
to fit in upstream windows") fails to boot on sparc/T5-8:

  pci 0000:06:00.0: reg 0x184: can't handle BAR above 4GB (bus address 0x110204000)

The problem is that sparc64 assumed that dma_addr_t only needed to hold DMA
addresses, i.e., bus addresses returned via the DMA API (dma_map_single(),
etc.), while the PCI core assumed dma_addr_t could hold *any* bus address,
including raw BAR values.  On sparc64, all DMA addresses fit in 32 bits, so
dma_addr_t is a 32-bit type.  However, BAR values can be 64 bits wide, so
they don't fit in a dma_addr_t.  d63e2e1f3d added new checking that
tripped over this mismatch.

Add pci_bus_addr_t, which is wide enough to hold any PCI bus address,
including both raw BAR values and DMA addresses.  This will be 64 bits
on 64-bit platforms and on platforms with a 64-bit dma_addr_t.  Then
dma_addr_t only needs to be wide enough to hold addresses from the DMA API.

[bhelgaas: changelog, bugzilla, Kconfig to ensure pci_bus_addr_t is at
least as wide as dma_addr_t, documentation]
Fixes: d63e2e1f3d ("sparc/PCI: Clip bridge windows to fit in upstream windows")
Fixes: 23b13bc76f ("PCI: Fail safely if we can't handle BARs larger than 4GB")
Link: http://lkml.kernel.org/r/CAE9FiQU1gJY1LYrxs+ma5LCTEEe4xmtjRG0aXJ9K_Tsu+m9Wuw@mail.gmail.com
Link: http://lkml.kernel.org/r/1427857069-6789-1-git-send-email-yinghai@kernel.org
Link: https://bugzilla.kernel.org/show_bug.cgi?id=96231
Reported-by: David Ahern <david.ahern@oracle.com>
Tested-by: David Ahern <david.ahern@oracle.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: David S. Miller <davem@davemloft.net>
CC: stable@vger.kernel.org	# v3.19+
2015-05-29 17:21:45 -05:00
Bjorn Helgaas
f311a724a7 DMA-API: Capitalize "CPU" consistently
Sometimes we used "cpu," other times "CPU."  Use "CPU" consistently.

Suggested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2014-05-26 17:28:27 -06:00
Bjorn Helgaas
88a984ba07 DMA-API: Change dma_declare_coherent_memory() CPU address to phys_addr_t
dma_declare_coherent_memory() takes two addresses for a region of memory: a
"bus_addr" and a "device_addr".  I think the intent is that "bus_addr" is
the physical address a *CPU* would use to access the region, and
"device_addr" is the bus address the *device* would use to address the
region.

Rename "bus_addr" to "phys_addr" and change its type to phys_addr_t.
Most callers already supply a phys_addr_t for this argument.  The others
supply a 32-bit integer (a constant, unsigned int, or __u32) and need no
change.

Use "unsigned long", not phys_addr_t, to hold PFNs.

No functional change (this could theoretically fix a truncation in a config
with 32-bit dma_addr_t and 64-bit phys_addr_t, but I don't think there are
any such cases involving this code).

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: James Bottomley <jbottomley@Parallels.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
2014-05-20 16:55:23 -06:00
Bjorn Helgaas
77f2ea2f8d DMA-API: Clarify physical/bus address distinction
The DMA-API documentation sometimes refers to "physical addresses" when it
really means "bus addresses."  Sometimes these are identical, but they may
be different if the bridge leading to the bus performs address translation.
Update the documentation to use "bus address" when appropriate.

Also, consistently capitalize "DMA", use parens with function names, use
dev_printk() in examples, and reword a few sections for clarity.

No functional change; documentation changes only.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: James Bottomley <jbottomley@Parallels.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
2014-05-20 16:54:21 -06:00
Russell King
4aa806b771 DMA-API: provide a helper to set both DMA and coherent DMA masks
Provide a helper to set both the DMA and coherent DMA masks to the
same value - this avoids duplicated code in a number of drivers,
sometimes with buggy error handling, and also allows us identify
which drivers do things differently.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-09-17 15:32:37 +01:00
Shuah Khan
6c9c6d6301 dma-debug: New interfaces to debug dma mapping errors
Add dma-debug interface debug_dma_mapping_error() to debug
drivers that fail to check dma mapping errors on addresses
returned by dma_map_single() and dma_map_page() interfaces.
This interface clears a flag set by debug_dma_map_page() to
indicate that dma_mapping_error() has been called by the
driver. When driver does unmap, debug_dma_unmap() checks the
flag and if this flag is still set, prints warning message
that includes call trace that leads up to the unmap. This
interface can be called from dma_mapping_error() routines to
enable dma mapping error check debugging.

Tested: Intel iommu and swiotlb (iommu=soft) on x86-64 with
        CONFIG_DMA_API_DEBUG enabled and disabled.

Signed-off-by: Shuah Khan <shuah.khan@hp.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2012-10-24 17:06:43 +02:00
Andrew Morton
842fa69f3e include/linux/dma-mapping.h: add dma_zalloc_coherent()
Lots of driver code does a dma_alloc_coherent() and then zeroes out the
memory with a memset.  Make it easy for them.

Cc: Alexandre Bounine <alexandre.bounine@idt.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-11-02 16:07:02 -07:00
FUJITA Tomonori
3b9c6c11f5 dma-mapping: remove dma_is_consistent API
Architectures implement dma_is_consistent() in different ways (some
misinterpret the definition of API in DMA-API.txt).  So it hasn't been so
useful for drivers.  We have only one user of the API in tree.  Unlikely
out-of-tree drivers use the API.

Even if we fix dma_is_consistent() in some architectures, it doesn't look
useful at all.  It was invented long ago for some old systems that can't
allocate coherent memory at all.  It's better to export only APIs that are
definitely necessary for drivers.

Let's remove this API.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-11 08:59:21 -07:00
FUJITA Tomonori
51e7364ef2 Documentation: rename PCI-DMA-mapping.txt to DMA-API-HOWTO.txt
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-12 15:52:43 -08:00
FUJITA Tomonori
f5a69f4c13 Documentation: remove the PCI DMA API description in DMA-API.txt
- remove the PCI DMA API description in DMA-API.txt
- remove the descriptions of dma_unmap macros since
  PCI-DMA-mapping.txt has the same description.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: "David S. Miller" <davem@davemloft.net>
Reviewed-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-12 15:52:43 -08:00
FUJITA Tomonori
6a1961f49e dma-mapping: dma-mapping.h: add dma_set_coherent_mask
dma_set_coherent_mask corresponds to pci_set_consistent_dma_mask.  This is
necessary to move to the generic device model DMA API from the PCI bus
specific API in the long term.

dma_set_coherent_mask works in the exact same way that
pci_set_consistent_dma_mask does.  So this patch also changes
pci_set_consistent_dma_mask to call dma_set_coherent_mask.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: James Bottomley <James.Bottomley@suse.de>
Cc: David S. Miller <davem@davemloft.net>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Greg KH <greg@kroah.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-12 15:52:42 -08:00
FUJITA Tomonori
0acedc124a dma-mapping.h: add the dma_unmap state API
Adds the following macros:

DECLARE_DMA_UNMAP_ADDR(ADDR_NAME)
DECLARE_DMA_UNMAP_LEN(LEN_NAME)
dma_unmap_addr(PTR, ADDR_NAME)
dma_unmap_addr_set(PTR, ADDR_NAME, VAL)
dma_unmap_len(PTR, LEN_NAME)
dma_unmap_len_set(PTR, LEN_NAME, VAL)

The API corresponds to the pci_unmap state API.  We'll move to this new
generic API from the PCI specific API in the long term.  As
include/asm-generic/pci-dma-compat.h does, the pci_unmap API simply calls
the new generic API for some time.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: James Bottomley <James.Bottomley@suse.de>
Cc: David S. Miller <davem@davemloft.net>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-12 15:52:42 -08:00
FUJITA Tomonori
8127bfc564 DMA-API.txt: remove dma_sync_single_range description
dma_sync_single_for_cpu/for_device supports a partial sync so there is no
point to have dma_sync_single_range (also dma_sync_single was obsoleted
long ago, replaced with dma_sync_single_for_cpu/for_device).

There is no user of dma_sync_single_range() in mainline and only Alpha
architecture supports dma_sync_single_range().  So it's unlikely that
someone out of the tree uses it.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: David Miller <davem@davemloft.net>
Acked-by: James Bottomley <James.Bottomley@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-12 15:52:40 -08:00
FUJITA Tomonori
9705ef7ec8 DMA-API.txt: add dma_sync_single/sg API description
This adds the description of the following eight function:

dma_sync_single_for_cpu
pci_dma_sync_single_for_cpu
dma_sync_single_for_device
pci_dma_sync_single_for_device
dma_sync_sg_for_cpu
pci_dma_sync_sg_for_cpu
dma_sync_sg_for_device
pci_dma_sync_sg_for_device

It was unclear that the API permits a partial sync (some network drivers
already do though).  I made it clear that the sync_single API can do a
partial sync but the sync_sg API can't.

We could do a partial sync with the sync_sg API too, however, it's
difficult for driver writers to correctly use the sync_sg API for a
partial sync since the scatterlists passed in to the mapping API can't be
modified.  It's unlikely that driver writers want to do a partial sync
with the sync_sg API (because the sync_sg API are usually used for block
drivers).  So I think that it's better to forbid a partial sync with the
sync_sg API.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: David Miller <davem@davemloft.net>
Acked-by: James Bottomley <James.Bottomley@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-12 15:52:40 -08:00
FUJITA Tomonori
039956e919 Documentation/DMA-API.txt: remove deprecated function descriptions
dma_sync_single(), pci_dma_sync_single(), dma_sync_sg(), and
pci_dma_sync_sg() are deprecated.  We should not advertise them.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Joerg Roedel <joro@8bytes.org>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-12 15:52:40 -08:00
Matt LaPlante
19f5946001 trivial: Miscellaneous documentation typo fixes
Fix various typos in documentation txts.

Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2009-06-12 18:01:47 +02:00
Joerg Roedel
016ea6874a dma-debug: add documentation for the driver filter
This patch adds the driver filter feature to the dma-debug
documentation.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2009-06-02 16:21:42 +02:00
Joerg Roedel
187f9c3f05 dma-debug: Documentation update
Impact: add documentation about DMA-API debugging to DMA-API.txt

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2009-03-17 12:56:47 +01:00
Randy Dunlap
5872fb94f8 Documentation: move DMA-mapping.txt to Doc/PCI/
Move DMA-mapping.txt to Documentation/PCI/.

DMA-mapping.txt was supposed to be moved from Documentation/ to
Documentation/PCI/.  The 00-INDEX files in those two directories
were updated, along with a few other text files, but the file
itself somehow escaped being moved, so move it and update more
text files and source files with its new location.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
cc:	Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-29 18:19:29 -08:00
John Keller
175add1981 [IA64] SN specific version of dma_get_required_mask()
Create a platform specific version of dma_get_required_mask()
for ia64 SN Altix. All SN Altix platforms support 64 bit DMA
addressing regardless of the size of system memory.
Create an ia64 machvec for dma_get_required_mask, with the
SN version unconditionally returning DMA_64BIT_MASK.

Signed-off-by: John Keller <jpk@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2009-01-15 10:42:16 -08:00
FUJITA Tomonori
1d678f365d DMA-API.txt: fix description of pci_map_sg/dma_map_sg scatterlists handling
- pci_map_sg/dma_map_sg are used with a scatter gather list that doesn't
  come from the block layer (e.g.  some network drivers do).

- how IOMMUs merge adjacent elements of the scatter/gather list is
  independent of how the block layer determines sees elements.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Tejun Heo <htejun@gmail.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-12-01 19:55:24 -08:00
FUJITA Tomonori
79eb014578 fix an example of scatterlists handling in DMA-API.txt
This example isn't the proper way to handle scatterlists (can't handle
sg chaining).

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:18 +02:00
FUJITA Tomonori
8d8bb39b9e dma-mapping: add the device argument to dma_mapping_error()
Add per-device dma_mapping_ops support for CONFIG_X86_64 as POWER
architecture does:

This enables us to cleanly fix the Calgary IOMMU issue that some devices
are not behind the IOMMU (http://lkml.org/lkml/2008/5/8/423).

I think that per-device dma_mapping_ops support would be also helpful for
KVM people to support PCI passthrough but Andi thinks that this makes it
difficult to support the PCI passthrough (see the above thread).  So I
CC'ed this to KVM camp.  Comments are appreciated.

A pointer to dma_mapping_ops to struct dev_archdata is added.  If the
pointer is non NULL, DMA operations in asm/dma-mapping.h use it.  If it's
NULL, the system-wide dma_ops pointer is used as before.

If it's useful for KVM people, I plan to implement a mechanism to register
a hook called when a new pci (or dma capable) device is created (it works
with hot plugging).  It enables IOMMUs to set up an appropriate
dma_mapping_ops per device.

The major obstacle is that dma_mapping_error doesn't take a pointer to the
device unlike other DMA operations.  So x86 can't have dma_mapping_ops per
device.  Note all the POWER IOMMUs use the same dma_mapping_error function
so this is not a problem for POWER but x86 IOMMUs use different
dma_mapping_error functions.

The first patch adds the device argument to dma_mapping_error.  The patch
is trivial but large since it touches lots of drivers and dma-mapping.h in
all the architecture.

This patch:

dma_mapping_error() doesn't take a pointer to the device unlike other DMA
operations.  So we can't have dma_mapping_ops per device.

Note that POWER already has dma_mapping_ops per device but all the POWER
IOMMUs use the same dma_mapping_error function.  x86 IOMMUs use device
argument.

[akpm@linux-foundation.org: fix sge]
[akpm@linux-foundation.org: fix svc_rdma]
[akpm@linux-foundation.org: build fix]
[akpm@linux-foundation.org: fix bnx2x]
[akpm@linux-foundation.org: fix s2io]
[akpm@linux-foundation.org: fix pasemi_mac]
[akpm@linux-foundation.org: fix sdhci]
[akpm@linux-foundation.org: build fix]
[akpm@linux-foundation.org: fix sparc]
[akpm@linux-foundation.org: fix ibmvscsi]
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Muli Ben-Yehuda <muli@il.ibm.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Avi Kivity <avi@qumranet.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-26 12:00:03 -07:00
Randy Dunlap
02d15c4322 doc: fix DMA-API function parameters
Fix kernel bugzilla #10388.

DMA-API.txt has wrong argument type for some functions.  It uses struct device
but should use struct pci_dev.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Acked-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:12 -07:00