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2014-05-26DMA-API: Capitalize "CPU" consistentlyBjorn Helgaas
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>
2014-05-20DMA-API: Change dma_declare_coherent_memory() CPU address to phys_addr_tBjorn Helgaas
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>
2014-05-20DMA-API: Clarify physical/bus address distinctionBjorn Helgaas
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 King
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 Khan
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>
2011-11-02include/linux/dma-mapping.h: add dma_zalloc_coherent()Andrew Morton
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 Tomonori
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>
2010-03-12Documentation: rename PCI-DMA-mapping.txt to DMA-API-HOWTO.txtFUJITA Tomonori
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>
2010-03-12Documentation: remove the PCI DMA API description in DMA-API.txtFUJITA Tomonori
- 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>
2010-03-12dma-mapping: dma-mapping.h: add dma_set_coherent_maskFUJITA Tomonori
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>
2010-03-12dma-mapping.h: add the dma_unmap state APIFUJITA Tomonori
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>
2010-03-12DMA-API.txt: remove dma_sync_single_range descriptionFUJITA Tomonori
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>
2010-03-12DMA-API.txt: add dma_sync_single/sg API descriptionFUJITA Tomonori
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>
2010-03-12Documentation/DMA-API.txt: remove deprecated function descriptionsFUJITA Tomonori
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 LaPlante
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 Roedel
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 Roedel
Impact: add documentation about DMA-API debugging to DMA-API.txt Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2009-01-29Documentation: move DMA-mapping.txt to Doc/PCI/Randy Dunlap
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 Keller
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>
2008-12-01DMA-API.txt: fix description of pci_map_sg/dma_map_sg scatterlists handlingFUJITA Tomonori
- 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 Tomonori
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 Tomonori
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 Dunlap
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>
2008-04-29dma: document dma_*map*_attrs() interfacesArthur Kepner
Document the new dma_*map*_attrs() functions. [markn@au1.ibm.com: fix up for dma-add-dma_map_attrs-interfaces and update docs] Signed-off-by: Arthur Kepner <akepner@sgi.com> Acked-by: David S. Miller <davem@davemloft.net> Cc: Tony Luck <tony.luck@intel.com> Cc: Jesse Barnes <jbarnes@virtuousgeek.org> Cc: Jes Sorensen <jes@sgi.com> Cc: Randy Dunlap <randy.dunlap@oracle.com> Cc: Roland Dreier <rdreier@cisco.com> Cc: James Bottomley <James.Bottomley@HansenPartnership.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Grant Grundler <grundler@parisc-linux.org> Cc: Michael Ellerman <michael@ellerman.id.au> Signed-off-by: Mark Nelson <markn@au1.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-12dma_free_coherent() needs irqs enabled (sigh)David Brownell
On at least ARM (and I'm told MIPS too) dma_free_coherent() has a newish call context requirement: unlike its dma_alloc_coherent() sibling, it may not be called with IRQs disabled. (This was new behavior on ARM as of late 2005, caused by ARM SMP updates.) This little surprise can be annoyingly driver-visible. Since it looks like that restriction won't be removed, this patch changes the definition of the API to include that requirement. Also, to help catch nonportable drivers, it updates the x86 and swiotlb versions to include the relevant warnings. (I already observed that it trips on the bus_reset_tasklet of the new firewire_ohci driver.) Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Cc: David Miller <davem@davemloft.net> Acked-by: Russell King <rmk@arm.linux.org.uk> Cc: Andi Kleen <ak@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-07-31Doc: DMA-API updateRandy Dunlap
Fix typos and update function parameters. Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Acked-by: Muli Ben-Yehuda <muli@il.ibm.com> Cc: James Bottomley <James.Bottomley@steeleye.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2006-12-07[PATCH] Pass struct dev pointer to dma_cache_sync()Ralf Baechle
Pass struct dev pointer to dma_cache_sync() dma_cache_sync() is ill-designed in that it does not have a struct device pointer argument which makes proper support for systems that consist of a mix of coherent and non-coherent DMA devices hard. Change dma_cache_sync to take a struct device pointer as first argument and fix all its callers to pass it. Signed-off-by: Ralf Baechle <ralf@linux-mips.org> Cc: James Bottomley <James.Bottomley@steeleye.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-07[PATCH] Add struct dev pointer to dma_is_consistent()Ralf Baechle
dma_is_consistent() is ill-designed in that it does not have a struct device pointer argument which makes proper support for systems that consist of a mix of coherent and non-coherent DMA devices hard. Change dma_is_consistent to take a struct device pointer as first argument and fix the sole caller to pass it. Signed-off-by: Ralf Baechle <ralf@linux-mips.org> Cc: James Bottomley <James.Bottomley@steeleye.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-07[PATCH] slab: remove kmem_cache_tChristoph Lameter
Replace all uses of kmem_cache_t with struct kmem_cache. The patch was generated using the following script: #!/bin/sh # # Replace one string by another in all the kernel sources. # set -e for file in `find * -name "*.c" -o -name "*.h"|xargs grep -l $1`; do quilt add $file sed -e "1,\$s/$1/$2/g" $file >/tmp/$$ mv /tmp/$$ $file quilt refresh done The script was run like this sh replace kmem_cache_t "struct kmem_cache" Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-11-30Fix typos in /Documentation : 'U-Z'Matt LaPlante
This patch fixes typos in various Documentation txts. The patch addresses some +words starting with the letters 'U-Z'. Looks like I made it through the alphabet...just in time to start over again +too! Maybe I can fit more profound fixes into the next round...? Time will +tell. :) Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com> Acked-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-04-14[PATCH] dma doc updatesDavid Brownell
This updates the DMA API documentation to address a few issues: - The dma_map_sg() call results are used like pci_map_sg() results: using sg_dma_address() and sg_dma_len(). That's not wholly obvious to folk reading _only_ the "new" DMA-API.txt writeup. - Buffers allocated by dma_alloc_coherent() may not be completely free of coherency concerns ... some CPUs also have write buffers that may need to be flushed. - Cacheline coherence issues are now mentioned as being among issues which affect dma buffers, and complicate/prevent using of static and (especially) stack based buffers with the DMA calls. I don't think many drivers currently need to worry about flushing write buffers, but I did hit it with one SOC using external SDRAM for DMA descriptors: without explicit writebuffer flushing, the on-chip DMA controller accessed descriptors before the CPU completed the writes. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-09-10[PATCH] Spelling fixes for Documentation/Tobias Klauser
The attached patch fixes the following spelling errors in Documentation/ - double "the" - Several misspellings of function/functionality - infomation - memeory - Recieved - wether and possibly others which I forgot ;-) Trailing whitespaces on the same line as the typo are also deleted. Signed-off-by: Tobias Klauser <tklauser@nuerscht.ch> Signed-off-by: Domen Puncer <domen@coderock.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-04-16Linux-2.6.12-rc2v2.6.12-rc2Linus Torvalds
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!