linux-stable.git/include/linux/dma-mapping.h, branch v4.5.3

dma-mapping: avoid oops when parameter cpu_addr is null

2016-03-09T23:43:42+00:00

To keep consistent with kfree, which tolerate ptr is NULL.  We do this
because sometimes we may use goto statement, so that success and failure
case can share parts of the code.  But unfortunately, dma_free_coherent
called with parameter cpu_addr is null will cause oops, such as showed
below:

  Unable to handle kernel paging request at virtual address ffffffc020d3b2b8
  pgd = ffffffc083a61000
  [ffffffc020d3b2b8] *pgd=0000000000000000, *pud=0000000000000000
  CPU: 4 PID: 1489 Comm: malloc_dma_1 Tainted: G           O    4.1.12 #1
  Hardware name: ARM64 (DT)
  PC is at __dma_free_coherent.isra.10+0x74/0xc8
  LR is at __dma_free+0x9c/0xb0
  Process malloc_dma_1 (pid: 1489, stack limit = 0xffffffc0837fc020)
  [...]
  Call trace:
    __dma_free_coherent.isra.10+0x74/0xc8
    __dma_free+0x9c/0xb0
    malloc_dma+0x104/0x158 [dma_alloc_coherent_mtmalloc]
    kthread+0xec/0xfc

Signed-off-by: Zhen Lei 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

dma-mapping: use offset_in_page macro

2016-01-21T01:09:18+00:00

Use offset_in_page macro instead of (addr & ~PAGE_MASK).

Signed-off-by: Geliang Tang 
Acked-by: Will Deacon 
Cc: Christian Borntraeger 
Cc: Joerg Roedel 
Cc: Sebastian Ott 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

dma-mapping: remove

2016-01-21T01:09:18+00:00

This wasn't an asm-generic header to start with, and can be merged into
dma-mapping.h trivially.

Signed-off-by: Christoph Hellwig 
Cc: "David S. Miller" 
Cc: Aurelien Jacquiot 
Cc: Chris Metcalf 
Cc: David Howells 
Cc: Geert Uytterhoeven 
Cc: Haavard Skinnemoen 
Cc: Hans-Christian Egtvedt 
Cc: Helge Deller 
Cc: James Hogan 
Cc: Jesper Nilsson 
Cc: Koichi Yasutake 
Cc: Ley Foon Tan 
Cc: Mark Salter 
Cc: Mikael Starvik 
Cc: Steven Miao 
Cc: Vineet Gupta 
Cc: Christian Borntraeger 
Cc: Joerg Roedel 
Cc: Sebastian Ott 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

dma-mapping: always provide the dma_map_ops based implementation

2016-01-21T01:09:18+00:00

Move the generic implementation to  now that all
architectures support it and remove the HAVE_DMA_ATTR Kconfig symbol now
that everyone supports them.

[valentinrothberg@gmail.com: remove leftovers in Kconfig]
Signed-off-by: Christoph Hellwig 
Cc: "David S. Miller" 
Cc: Aurelien Jacquiot 
Cc: Chris Metcalf 
Cc: David Howells 
Cc: Geert Uytterhoeven 
Cc: Haavard Skinnemoen 
Cc: Hans-Christian Egtvedt 
Cc: Helge Deller 
Cc: James Hogan 
Cc: Jesper Nilsson 
Cc: Koichi Yasutake 
Cc: Ley Foon Tan 
Cc: Mark Salter 
Cc: Mikael Starvik 
Cc: Steven Miao 
Cc: Vineet Gupta 
Cc: Christian Borntraeger 
Cc: Joerg Roedel 
Cc: Sebastian Ott 
Signed-off-by: Valentin Rothberg 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

dma-mapping: tidy up dma_parms default handling

2015-11-07T01:50:42+00:00

Many DMA controllers and other devices set max_segment_size to
indicate their scatter-gather capability, but have no interest in
segment_boundary_mask. However, the existence of a dma_parms structure
precludes the use of any default value, leaving them as zeros (assuming
a properly kzalloc'ed structure). If a well-behaved IOMMU (or SWIOTLB)
then tries to respect this by ensuring a mapped segment does not cross
a zero-byte boundary, hilarity ensues.

Since zero is a nonsensical value for either parameter, treat it as an
indicator for "default", as might be expected. In the process, clean up
a bit by replacing the bare constants with slightly more meaningful
macros and removing the superfluous "else" statements.

[akpm@linux-foundation.org: dma-mapping.h needs sizes.h for SZ_64K]
Signed-off-by: Robin Murphy 
Reviewed-by: Sumit Semwal 
Acked-by: Marek Szyprowski 
Cc: Arnd Bergmann 
Cc: Sakari Ailus 
Cc: Russell King 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

include/dma-mapping: Clarify output of dma_map_sg

2015-03-09T12:05:47+00:00

Although dma_map_sg returns 0 on error and it cannot return a
value < 0, the function returns a signed integer.

Most of the time, this function is used with a scatterlist structure.
This structure uses an unsigned integer for the number of memory.

A dma developer that has not read in detail DMA-API.txt, can wrongly
return a value < 0 on error.

Signed-off-by: Ricardo Ribalda Delgado 
Signed-off-by: Marek Szyprowski

dma-mapping: detect and configure IOMMU in of_dma_configure

2014-12-01T16:50:45+00:00

This patch extends of_dma_configure so that it sets up the IOMMU for a
device, as well as the coherent/non-coherent DMA mapping ops.

Acked-by: Arnd Bergmann 
Acked-by: Marek Szyprowski 
Tested-by: Robin Murphy 
Signed-off-by: Will Deacon

dma-mapping: replace set_arch_dma_coherent_ops with arch_setup_dma_ops

2014-12-01T16:50:32+00:00

set_arch_dma_coherent_ops is called from of_dma_configure in order to
swizzle the architectural dma-mapping functions over to a cache-coherent
implementation. This is currently implemented only for ARM.

In anticipation of re-using this mechanism for IOMMU-backed dma-mapping
ops too, this patch replaces the function with a broader
arch_setup_dma_ops callback which will be extended in future.

Acked-by: Arnd Bergmann 
Acked-by: Marek Szyprowski 
Tested-by: Robin Murphy 
Signed-off-by: Will Deacon

dma-mapping: Provide write-combine allocations

2014-08-26T05:39:13+00:00

Provide an implementation for dma_{alloc,free,mmap}_writecombine() when
the architecture supports DMA attributes.

Signed-off-by: Thierry Reding 
Acked-by: Arnd Bergmann 
Signed-off-by: Marek Szyprowski

Merge branch 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm into next

2014-06-05T22:57:04+00:00

Pull ARM updates from Russell King:

 - Major clean-up of the L2 cache support code.  The existing mess was
   becoming rather unmaintainable through all the additions that others
   have done over time.  This turns it into a much nicer structure, and
   implements a few performance improvements as well.

 - Clean up some of the CP15 control register tweaks for alignment
   support, moving some code and data into alignment.c

 - DMA properties for ARM, from Santosh and reviewed by DT people.  This
   adds DT properties to specify bus translations we can't discover
   automatically, and to indicate whether devices are coherent.

 - Hibernation support for ARM

 - Make ftrace work with read-only text in modules

 - add suspend support for PJ4B CPUs

 - rework interrupt masking for undefined instruction handling, which
   allows us to enable interrupts earlier in the handling of these
   exceptions.

 - support for big endian page tables

 - fix stacktrace support to exclude stacktrace functions from the
   trace, and add save_stack_trace_regs() implementation so that kprobes
   can record stack traces.

 - Add support for the Cortex-A17 CPU.

 - Remove last vestiges of ARM710 support.

 - Removal of ARM "meminfo" structure, finally converting us solely to
   memblock to handle the early memory initialisation.

* 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm: (142 commits)
  ARM: ensure C page table setup code follows assembly code (part II)
  ARM: ensure C page table setup code follows assembly code
  ARM: consolidate last remaining open-coded alignment trap enable
  ARM: remove global cr_no_alignment
  ARM: remove CPU_CP15 conditional from alignment.c
  ARM: remove unused adjust_cr() function
  ARM: move "noalign" command line option to alignment.c
  ARM: provide common method to clear bits in CPU control register
  ARM: 8025/1: Get rid of meminfo
  ARM: 8060/1: mm: allow sub-architectures to override PCI I/O memory type
  ARM: 8066/1: correction for ARM patch 8031/2
  ARM: 8049/1: ftrace/add save_stack_trace_regs() implementation
  ARM: 8065/1: remove last use of CONFIG_CPU_ARM710
  ARM: 8062/1: Modify ldrt fixup handler to re-execute the userspace instruction
  ARM: 8047/1: rwsem: use asm-generic rwsem implementation
  ARM: l2c: trial at enabling some Cortex-A9 optimisations
  ARM: l2c: add warnings for stuff modifying aux_ctrl register values
  ARM: l2c: print a warning with L2C-310 caches if the cache size is modified
  ARM: l2c: remove old .set_debug method
  ARM: l2c: kill L2X0_AUX_CTRL_MASK before anyone else makes use of this
  ...