Drivers/subsystems creating scatterlists for DMA should be taking care
to respect the scatter-gather limitations of the appropriate device, as
described by dma_parms. A DMA API implementation cannot feasibly split
a scatterlist into *more* entries than originally passed, so it is not
well defined what they should do when given a segment larger than the
limit they are also required to respect.
Conversely, devices which are less limited than the rather conservative
defaults, or indeed have no limitations at all (e.g. GPUs with their own
internal MMU), should be encouraged to set appropriate dma_parms, as
they may get more efficient DMA mapping performance out of it.
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Only used by the AMD GART and Intel VT-D drivers, which must be built in.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Just keep a single variable with a descriptive name instead of two
with confusing names.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Most mainstream architectures are using 65536 entries, so lets stick to
that. If someone is really desperate to override it that can still be
done through <asm/dma-mapping.h>, but I'd rather see a really good
rationale for that.
dma_debug_init is now called as a core_initcall, which for many
architectures means much earlier, and provides dma-debug functionality
earlier in the boot process. This should be safe as it only relies
on the memory allocator already being available.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Marty reported a memory leakage introduced by commit 3aaabbf1c3
("lib/dma-debug.c: fix incorrect pfn calculation"). Fix it
by checking the virtual address before allocating the entry.
This patch also use virt_addr_valid() instead of virt_to_page()
to check if a virtual address is linear.
Fixes: 3aaabbf1 ("lib/dma-debug.c: fix incorrect pfn calculation")
Reported-by: Marty Faltesek <mfaltesek@google.com>
Signed-off-by: Miles Chen <miles.chen@mediatek.com>
Acked-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
dma-debug reports the following warning:
WARNING: CPU: 3 PID: 298 at kernel-4.4/lib/dma-debug.c:604
debug _dma_assert_idle+0x1a8/0x230()
DMA-API: cpu touching an active dma mapped cacheline [cln=0x00000882300]
CPU: 3 PID: 298 Comm: vold Tainted: G W O 4.4.22+ #1
Hardware name: MT6739 (DT)
Call trace:
debug_dma_assert_idle+0x1a8/0x230
wp_page_copy.isra.96+0x118/0x520
do_wp_page+0x4fc/0x534
handle_mm_fault+0xd4c/0x1310
do_page_fault+0x1c8/0x394
do_mem_abort+0x50/0xec
I found that debug_dma_alloc_coherent() and debug_dma_free_coherent()
assume that dma_alloc_coherent() always returns a linear address.
However it's possible that dma_alloc_coherent() returns a non-linear
address. In this case, page_to_pfn(virt_to_page(virt)) will return an
incorrect pfn. If the pfn is valid and mapped as a COW page, we will
hit the warning when doing wp_page_copy().
Fix this by calculating pfn for linear and non-linear addresses.
[miles.chen@mediatek.com: v4]
Link: http://lkml.kernel.org/r/1510872972-23919-1-git-send-email-miles.chen@mediatek.com
Link: http://lkml.kernel.org/r/1506484087-1177-1-git-send-email-miles.chen@mediatek.com
Signed-off-by: Miles Chen <miles.chen@mediatek.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull dmaengine updates from Vinod Koul:
"This time again a smaller update consisting of:
- support for TI DA8xx dma controller and updates to the cppi driver
- updates on bunch of drivers like xilinx, pl08x, stm32-dma, mv_xor,
ioat, dmatest"
* tag 'dmaengine-4.12-rc1' of git://git.infradead.org/users/vkoul/slave-dma: (35 commits)
dmaengine: pl08x: remove lock documentation
dmaengine: pl08x: fix pl08x_dma_chan_state documentation
dmaengine: pl08x: Use the BIT() macro consistently
dmaengine: pl080: Fix some missing kerneldoc
dmaengine: pl080: Cut some unused defines
dmaengine: dmatest: Add check for supported buffer count (sg_buffers)
dmaengine: dmatest: Select DMA_ENGINE_RAID as its needed for the slave_sg test
dmaengine: virt-dma: Convert to use list_for_each_entry_safe()
dma-debug: use offset_in_page() macro
dmaengine: mv_xor: use offset_in_page() macro
dmaengine: dmatest: use offset_in_page() macro
dmaengine: sun4i: fix invalid argument
dmaengine: ioat: use setup_timer
dmaengine: cppi41: Fix an Oops happening in cppi41_dma_probe()
dmaengine: pl330: remove pdata based initialization
dmaengine: cppi: fix build error due to bad variable
dmaengine: imx-sdma: add 1ms delay to ensure SDMA channel is stopped
dmaengine: cppi41: use managed functions devm_*()
dmaengine: cppi41: fix cppi41_dma_tx_status() logic
dmaengine: qcom_hidma: pause the channel on shutdown
...
We are going to split <linux/sched/task_stack.h> out of <linux/sched.h>, which
will have to be picked up from other headers and a couple of .c files.
Create a trivial placeholder <linux/sched/task_stack.h> file that just
maps to <linux/sched.h> to make this patch obviously correct and
bisectable.
Include the new header in the files that are going to need it.
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
We are going to split <linux/sched/task.h> out of <linux/sched.h>, which
will have to be picked up from other headers and a couple of .c files.
Create a trivial placeholder <linux/sched/task.h> file that just
maps to <linux/sched.h> to make this patch obviously correct and
bisectable.
Include the new header in the files that are going to need it.
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull dmaengine updates from Vinod Koul:
"This is bit large pile of code which bring in some nice additions:
- Error reporting: we have added a new mechanism for users of
dmaenegine to register a callback_result which tells them the
result of the dma transaction. Right now only one user (ntb) is
using it.
- As we discussed on KS mailing list and pointed out NO_IRQ has no
place in kernel, this also remove NO_IRQ from dmaengine subsystem
(both arm and ppc users)
- Support for IOMMU slave transfers and its implementation for arm.
- To get better build coverage, enable COMPILE_TEST for bunch of
driver, and fix the warning and sparse complaints on these.
- Apart from above, usual updates spread across drivers"
* tag 'dmaengine-4.9-rc1' of git://git.infradead.org/users/vkoul/slave-dma: (169 commits)
async_pq_val: fix DMA memory leak
dmaengine: virt-dma: move function declarations
dmaengine: omap-dma: Enable burst and data pack for SG
DT: dmaengine: rcar-dmac: document R8A7743/5 support
dmaengine: fsldma: Unmap region obtained by of_iomap
dmaengine: jz4780: fix resource leaks on error exit return
dma-debug: fix ia64 build, use PHYS_PFN
dmaengine: coh901318: fix integer overflow when shifting more than 32 places
dmaengine: edma: avoid uninitialized variable use
dma-mapping: fix m32r build warning
dma-mapping: fix ia64 build, use PHYS_PFN
dmaengine: ti-dma-crossbar: enable COMPILE_TEST
dmaengine: omap-dma: enable COMPILE_TEST
dmaengine: edma: enable COMPILE_TEST
dmaengine: ti-dma-crossbar: Fix of_device_id data parameter usage
dmaengine: ti-dma-crossbar: Correct type for of_find_property() third parameter
dmaengine/ARM: omap-dma: Fix the DMAengine compile test on non OMAP configs
dmaengine: edma: Rename set_bits and remove unused clear_bits helper
dmaengine: edma: Use correct type for of_find_property() third parameter
dmaengine: edma: Fix of_device_id data parameter usage (legacy vs TPCC)
...
kbuild test robot reports:
lib/dma-debug.c: In function 'debug_dma_map_resource':
>> lib/dma-debug.c:1541:16: error: implicit declaration of function '__phys_to_pfn' [-Werror=implicit-function-declaration]
entry->pfn = __phys_to_pfn(addr);
^~~~~~~~~~~~~
ia64 does not provide __phys_to_pfn(), use the PHYS_PFN() alias.
Fixes: 0e74b34dfc ("dma-debug: add support for resource mappings")
Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
A MMIO mapped resource can not be represented by a struct page so a new
debug type is needed to handle this. This patch add such type and
functionality to add/remove entries and how to translate them to a
physical address.
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>
get_hash_bucket() and put_hash_bucket() acquire and release the same
spinlock, but this confuses static checkers such as sparse
lib/dma-debug.c:254:27: warning: context imbalance in 'get_hash_bucket' - wrong count at exit
lib/dma-debug.c:268:13: warning: context imbalance in 'put_hash_bucket' - unexpected unlock
Add the appropriate acquire and release statements so that checkers can
properly track the lock state.
Link: http://lkml.kernel.org/r/20160701191552.24295-1-sboyd@codeaurora.org
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In include/asm-generic/sections.h:
/*
* Usage guidelines:
* _text, _data: architecture specific, don't use them in
* arch-independent code
* [_stext, _etext]: contains .text.* sections, may also contain
* .rodata.*
* and/or .init.* sections
_text is not guaranteed across architectures. Architectures such as ARM
may reuse parts which are not actually text and erroneously trigger a bug.
Switch to using _stext which is guaranteed to contain text sections.
Came out of https://lkml.kernel.org/g/<567B1176.4000106@redhat.com>
Signed-off-by: Laura Abbott <labbott@fedoraproject.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
dma-debug uses struct dma_debug_entry to keep track of dma coherent
memory allocation requests. The virtual address is converted into a pfn
and an offset. Previously, the offset was calculated using an incorrect
bit mask. As a result, we saw incorrect error messages from dma-debug
like the following:
"DMA-API: exceeded 7 overlapping mappings of cacheline 0x03e00000"
Cacheline 0x03e00000 does not exist on our platform.
Cc: <stable@vger.kernel.org>
Fixes: 0abdd7a81b ("dma-debug: introduce debug_dma_assert_idle()")
Signed-off-by: Daniel Mentz <danielmentz@google.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Its a bit odd that debugfs_create_bool() takes 'u32 *' as an argument,
when all it needs is a boolean pointer.
It would be better to update this API to make it accept 'bool *'
instead, as that will make it more consistent and often more convenient.
Over that bool takes just a byte.
That required updates to all user sites as well, in the same commit
updating the API. regmap core was also using
debugfs_{read|write}_file_bool(), directly and variable types were
updated for that to be bool as well.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Mark Brown <broonie@kernel.org>
Acked-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
bucket_find_contain() will search the bucket list for a dma_debug_entry.
When the entry isn't found it needs to search other buckets too, since
only the start address of a dma range is hashed (which might be in a
different bucket).
A copy of the dma_debug_entry is used to get the previous hash bucket
but when its list is searched the original dma_debug_entry is to be used
not its modified copy.
This fixes false "device driver tries to sync DMA memory it has not allocated"
warnings.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Horia Geanta <horia.geanta@freescale.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
dma_debug_init() is called by architecture specific code at different
levels, but typically as a fs_initcall due to the debugfs initialization.
Some platforms may have early callers of the DMA-API, running prior to the
fs_initcall() level, which is not much of an issue unless
CONFIG_DMA_API_DEBUG is set. When the DMA-API debugging facilities are
turned on a caller will go through:
debug_dma_map_{single,page}
-> dma_mapping_error (inline function usually)
-> debug_dma_mapping_error
-> get_hash_bucket
Calling get_hash_bucket() returns a valid hash value since we hash on high
bits of the dma_addr cookie, but we will grab an unitialized spinlock,
which typically won't crash but produce a warning, the real crash will
however happen during the bucket list traversal because the list has not
been initialized yet.
An obvious solution is of course to move some of the offenders to run
after the fs_initcall level, but since this might not always be an option,
we add a flag "dma_debug_initialized" which is set to false by default,
and set to true once dma_debug_init() has had a chance to run.
The dma_debug_disabled() helper function previously introduced just needs
to check for dma_debug_initialized to allow the caller to proceed or not.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Horia Geanta <horia.geanta@freescale.com>
Cc: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Robin Murphy
Christoph Hellwig
Miles Chen
Linus Torvalds
Pankaj Gupta
Geliang Tang
Ingo Molnar
Niklas Söderlund
Andy Lutomirski
Stephen Boyd
Ville Syrjälä
Laura Abbott
Daniel Mentz
Viresh Kumar
Haggai Eran
Sebastian Ott
Florian Fainelli