| Age | Commit message (Collapse) | Author | Files | Lines |
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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>
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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>
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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>
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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>
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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+
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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>
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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>
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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>
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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>
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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>
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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>
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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>
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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>
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- 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>
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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>
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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>
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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>
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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>
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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>
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Fix various typos in documentation txts.
Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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This patch adds the driver filter feature to the dma-debug
documentation.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
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Impact: add documentation about DMA-API debugging to DMA-API.txt
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
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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>
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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>
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- 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>
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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>
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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>
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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>
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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>
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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>
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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>
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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>
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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>
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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>
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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>
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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>
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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>
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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!
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