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2019-09-04dma-mapping: remove dma_release_declared_memoryChristoph Hellwig1-11/+0
This function is entirely unused given that declared memory is generally provided by platform setup code. Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-09-03dma-mapping: introduce dma_get_merge_boundary()Yoshihiro Shimoda1-0/+8
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>
2019-06-07Documentation: DMA-API: fix a function name of max_mapping_sizeYoshihiro Shimoda1-1/+1
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: 133d624b1cee ("dma: Introduce dma_max_mapping_size()") Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-03-10Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhostLinus Torvalds1-0/+8
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()
2019-03-10Merge tag 'dma-mapping-5.1' of git://git.infradead.org/users/hch/dma-mappingLinus Torvalds1-25/+4
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 ...
2019-03-06dma: Introduce dma_max_mapping_size()Joerg Roedel1-0/+8
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>
2019-02-20dma-mapping: remove the DMA_MEMORY_EXCLUSIVE flagChristoph Hellwig1-8/+1
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>
2019-02-20dma-mapping: remove dma_mark_declared_memory_occupiedChristoph Hellwig1-17/+0
This API is not used anywhere, so remove it. Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-02-01dma-debug: add dumping facility via debugfsCorentin Labbe1-0/+3
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>
2019-01-21Documentation: DMA-API: fix two typosCorentin Labbe1-3/+3
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>
2018-12-20dma-mapping: deprecate dma_zalloc_coherentChristoph Hellwig1-9/+0
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>
2018-12-11dma-debug: Batch dma_debug_entry allocationRobin Murphy1-1/+3
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>
2018-12-11dma-debug: Make leak-like behaviour apparentRobin Murphy1-1/+5
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>
2018-12-11dma-debug: Dynamically expand the dma_debug_entry poolRobin Murphy1-6/+5
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>
2018-12-11dma-debug: Expose nr_total_entries in debugfsRobin Murphy1-0/+3
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>
2017-09-01dma-coherent: remove the DMA_MEMORY_MAP and DMA_MEMORY_IO flagsChristoph Hellwig1-20/+1
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>
2017-09-01dma-coherent: remove the DMA_MEMORY_INCLUDES_CHILDREN flagChristoph Hellwig1-4/+0
This flag was never implemented or used. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Robin Murphy <robin.murphy@arm.com>
2017-08-29dma-mapping: remove dma_alloc_noncoherent and dma_free_noncoherentChristoph Hellwig1-14/+16
No users left, everyone switched to the _attrs versions. Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-07-14DMA-API.txt: standardize document formatMauro Carvalho Chehab1-251/+329
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>
2017-06-06Documentation: DMA API: fix a typo in a function nameWolfram Sang1-1/+1
Correct the typo, the wrongly typed function does not exist. Fixes: 6c9c6d6301287e ("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>
2016-09-26dma-mapping: add dma_{map,unmap}_resourceNiklas Söderlund1-5/+17
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>
2016-08-04dma-mapping: use unsigned long for dma_attrsKrzysztof Kozlowski1-19/+14
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>
2016-01-12DMA-API: fix confusing sentence in Documentation/DMA-API.txtMasahiro Yamada1-1/+1
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>
2015-11-10dma: remove external references to dma_supportedChristoph Hellwig1-13/+0
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>
2015-09-25Documentation: DMA API: Be more explicit that nents is always the sameSakari Ailus1-3/+3
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>
2015-09-09mm: add dma_pool_zalloc() call to DMA APISean O. Stalley1-0/+7
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>
2015-05-30PCI: Add pci_bus_addr_tYinghai Lu1-15/+15
David Ahern reported that d63e2e1f3df9 ("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. d63e2e1f3df9 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: d63e2e1f3df9 ("sparc/PCI: Clip bridge windows to fit in upstream windows") Fixes: 23b13bc76f35 ("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+
2014-05-27DMA-API: Capitalize "CPU" consistentlyBjorn Helgaas1-6/+6
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>
2014-05-21DMA-API: Change dma_declare_coherent_memory() CPU address to phys_addr_tBjorn Helgaas1-5/+4
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>
2014-05-21DMA-API: Clarify physical/bus address distinctionBjorn Helgaas1-67/+72
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>
2013-09-17DMA-API: provide a helper to set both DMA and coherent DMA masksRussell King1-0/+8
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>
2012-10-24dma-debug: New interfaces to debug dma mapping errorsShuah Khan1-0/+12
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>
2011-11-03include/linux/dma-mapping.h: add dma_zalloc_coherent()Andrew Morton1-0/+7
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>
2010-08-11dma-mapping: remove dma_is_consistent APIFUJITA Tomonori1-6/+0
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>
2010-03-13Documentation: rename PCI-DMA-mapping.txt to DMA-API-HOWTO.txtFUJITA Tomonori1-1/+1
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>
2010-03-13Documentation: remove the PCI DMA API description in DMA-API.txtFUJITA Tomonori1-137/+15
- 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>
2010-03-13dma-mapping: dma-mapping.h: add dma_set_coherent_maskFUJITA Tomonori1-0/+10
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>
2010-03-13dma-mapping.h: add the dma_unmap state APIFUJITA Tomonori1-0/+58
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>
2010-03-13DMA-API.txt: remove dma_sync_single_range descriptionFUJITA Tomonori1-10/+0
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>
2010-03-13DMA-API.txt: add dma_sync_single/sg API descriptionFUJITA Tomonori1-0/+42
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>
2010-03-13Documentation/DMA-API.txt: remove deprecated function descriptionsFUJITA Tomonori1-28/+0
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>
2009-06-12trivial: Miscellaneous documentation typo fixesMatt LaPlante1-2/+2
Fix various typos in documentation txts. Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2009-06-02dma-debug: add documentation for the driver filterJoerg Roedel1-0/+12
This patch adds the driver filter feature to the dma-debug documentation. Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2009-03-17dma-debug: Documentation updateJoerg Roedel1-0/+106
Impact: add documentation about DMA-API debugging to DMA-API.txt Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2009-01-30Documentation: move DMA-mapping.txt to Doc/PCI/Randy Dunlap1-1/+1
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>
2009-01-15[IA64] SN specific version of dma_get_required_mask()John Keller1-5/+4
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>
2008-12-02DMA-API.txt: fix description of pci_map_sg/dma_map_sg scatterlists handlingFUJITA Tomonori1-5/+3
- 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>
2008-10-09fix an example of scatterlists handling in DMA-API.txtFUJITA Tomonori1-1/+1
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>
2008-07-26dma-mapping: add the device argument to dma_mapping_error()FUJITA Tomonori1-2/+2
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>
2008-04-29doc: fix DMA-API function parametersRandy Dunlap1-2/+2
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>