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2015-09-24Documentation: DMA API: Be more explicit that nents is always the sameSakari Ailus1-0/+5
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>
2015-06-24Merge tag 'docs-for-linus' of git://git.lwn.net/linux-2.6Linus Torvalds1-2/+2
Pull documentation updates from Jonathan Corbet: "The main thing here is Ingo's big subdirectory documenting feature support for each architecture. Beyond that, it's the usual pile of fixes, tweaks, and small additions" * tag 'docs-for-linus' of git://git.lwn.net/linux-2.6: (79 commits) doc:md: fix typo in md.txt. Documentation/mic/mpssd: don't build x86 userspace when cross compiling Documentation/prctl: don't build tsc tests when cross compiling Documentation/vDSO: don't build tests when cross compiling Doc:ABI/testing: Fix typo in sysfs-bus-fcoe Doc: Docbook: Change wikipedia's URL from http to https in scsi.tmpl Doc: Change wikipedia's URL from http to https Documentation/kernel-parameters: add missing pciserial to the earlyprintk Doc:pps: Fix typo in pps.txt kbuild : Fix documentation of INSTALL_HDR_PATH Documentation: filesystems: updated struct file_operations documentation in vfs.txt kbuild: edit explanation of clean-files variable Doc: ja_JP: Fix typo in HOWTO Move freefall program from Documentation/ to tools/ Documentation: ARM: EXYNOS: Describe boot loaders interface Doc:nfc: Fix typo in nfc-hci.txt vfs: Minor documentation fix Doc: networking: txtimestamp: fix printf format warning Documentation, intel_pstate: Improve legacy mode internal governors description Documentation: extend use case for EXPORT_SYMBOL_GPL() ...
2015-05-29PCI: Add pci_bus_addr_tYinghai Lu1-12/+17
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+
2015-05-22DMA-API: Spelling s/This/Think/Geert Uytterhoeven1-2/+2
Also remove spaces before TABs while we're at it. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2014-09-26Documentation: correct parameter error for dma_mapping_errorLiu Hua1-3/+3
dma_mapping_error takes two parameters, but some of examples in Documentation/DMA-API-HOWTO.txt just takes one. So correct it. Signed-off-by: Liu Hua <sdu.liu@huawei.com> Acked-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2014-05-26DMA-API: Update dma_pool_create ()and dma_pool_alloc() descriptionsGioh Kim1-4/+4
Use "boundary" to be more descriptive than "alloc" in the dma_pool_create() documentation. Replace "SLAB_KERNEL" and "SLAB_ATOMIC" with the correct "GFP_KERNEL" and "GFP_ATOMIC." [bhelgaas: changelog] Signed-off-by: Gioh Kim <gioh.kim@lge.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2014-05-26DMA-API: Fix duplicated word in DMA-API-HOWTO.txtEmilio López1-4/+4
"coherent" is written twice when it should be just once. Signed-off-by: Emilio López <emilio@elopez.com.ar> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2014-05-26DMA-API: Capitalize "CPU" consistentlyBjorn Helgaas1-4/+4
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: Clarify physical/bus address distinctionBjorn Helgaas1-69/+123
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 King1-15/+22
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>
2013-02-27Documentation/DMA-API-HOWTO.txt: fix typoAndrew Morton1-1/+1
Noted by Jesper Cc: Jesper Juhl <jj@chaosbits.net> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Shuah Khan <shuah.khan@hp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-27Documentation/DMA-API-HOWTO.txt: minor grammar correctionsShuah Khan1-3/+4
Signed-off-by: Shuah Khan <shuah.khan@hp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-24Documentation DMA-API-HOWTO.txt Add dma mapping error check usage examplesShuah Khan1-0/+126
Enhance the document to discuss the importance of dma mapping error checks after dma_map_single() and dma_map_page() calls. Also added usage examples that include unmap examples in error paths when dma mapping error is returned. Includes correct and incorrect usages to high light some common mistakes in error paths especially when dma mapping fails when more than one dma mapping call is made. 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>
2011-07-26Documentation/DMA-API-HOWTO.txt: fix misleading exampleMichal Miroslaw1-6/+6
See: DMA-API.txt, part Id, DMA_FROM_DEVICE description. Signed-off-by: Michal Miroslaw <mirq-linux@rere.qmqm.pl> Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-14Documentation: DMA-API-HOWTO.txt: rename ARCH_KMALLOC_MINALIGN to ↵FUJITA Tomonori1-3/+3
ARCH_DMA_MINALIGN ARCH_KMALLOC_MINALIGN was renamed to ARCH_DMA_MINALIGN (the commit a6eb9fe105d5de0053b261148cee56c94b4720ca). ARCH_DMA_MINALIGN must be defined instead of ARCH_KMALLOC_MINALIGN to ensure that kmalloc'ed buffer is DMA-safe. Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-11Documentation: DMA-API-HOWTO.txt: add multiple types of IOMMUs supportFUJITA Tomonori1-0/+10
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27Documentation/DMA-API-HOWTO: add ARCH_KMALLOC_MINALIGN descriptionFUJITA Tomonori1-1/+14
Add ARCH_KMALLOC_MINALIGN description in "Platform Issues" section. Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Cc: "David S. Miller" <davem@davemloft.net> Cc: Matt Mackall <mpm@selenic.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27Documentation: move the error handling to the better place in DMA-API-HOWTOFUJITA Tomonori1-30/+30
Handing DMA mapping errors is essential. Let's put it in the more appropriate place rather than the end of the doc. Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27Documentation: update scatterlist struct description in DMA-API-HOWTOFUJITA Tomonori1-13/+4
Now we have <asm-generic/scatterlist.h>. Architectures should use it instead of inventing the own scatterlist struct. Let's update the description. Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27Documentation: add SCSI drivers' mapping error handling to DMA-API-HOWTOFUJITA Tomonori1-0/+4
Add the concrete DMA mapping error handling for SCSI drivers on the queuecommand path. Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Cc: James Bottomley <James.Bottomley@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27Documentation: add networking driver's mapping error handling to DMA-API-HOWTOFUJITA Tomonori1-0/+5
Adds the concrete DMA mapping error handling for Networking drivers on the transmit path. Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-04-23Documentation/: it's -> its where appropriateFrancis Galiegue1-1/+1
Fix obvious cases of "it's" being used when "its" was meant. Signed-off-by: Francis Galiegue <fgaliegue@gmail.com> Acked-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2010-03-24Documentation: rename PCI/PCI-DMA-mapping.txt to DMA-API-HOWTO.txtFUJITA Tomonori1-0/+758
This patch renames PCI/PCI-DMA-mapping.txt to DMA-API-HOWTO.txt. The commit 51e7364ef281e540371f084008732b13292622f0 "Documentation: rename PCI-DMA-mapping.txt to DMA-API-HOWTO.txt" was supposed to do this but it didn't. Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Acked-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>
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