• Linus Torvalds's avatar
    Merge branch 'for-linus' of git://git.linaro.org/people/mszyprowski/linux-dma-mapping · d484864d
    Linus Torvalds authored
    Pull CMA and ARM DMA-mapping updates from Marek Szyprowski:
     "These patches contain two major updates for DMA mapping subsystem
      (mainly for ARM architecture).  First one is Contiguous Memory
      Allocator (CMA) which makes it possible for device drivers to allocate
      big contiguous chunks of memory after the system has booted.
    
      The main difference from the similar frameworks is the fact that CMA
      allows to transparently reuse the memory region reserved for the big
      chunk allocation as a system memory, so no memory is wasted when no
      big chunk is allocated.  Once the alloc request is issued, the
      framework migrates system pages to create space for the required big
      chunk of physically contiguous memory.
    
      For more information one can refer to nice LWN articles:
    
       - 'A reworked contiguous memory allocator':
    		http://lwn.net/Articles/447405/
    
       - 'CMA and ARM':
    		http://lwn.net/Articles/450286/
    
       - 'A deep dive into CMA':
    		http://lwn.net/Articles/486301/
    
       - and the following thread with the patches and links to all previous
         versions:
    		https://lkml.org/lkml/2012/4/3/204
    
      The main client for this new framework is ARM DMA-mapping subsystem.
    
      The second part provides a complete redesign in ARM DMA-mapping
      subsystem.  The core implementation has been changed to use common
      struct dma_map_ops based infrastructure with the recent updates for
      new dma attributes merged in v3.4-rc2.  This allows to use more than
      one implementation of dma-mapping calls and change/select them on the
      struct device basis.  The first client of this new infractructure is
      dmabounce implementation which has been completely cut out of the
      core, common code.
    
      The last patch of this redesign update introduces a new, experimental
      implementation of dma-mapping calls on top of generic IOMMU framework.
      This lets ARM sub-platform to transparently use IOMMU for DMA-mapping
      calls if one provides required IOMMU hardware.
    
      For more information please refer to the following thread:
    		http://www.spinics.net/lists/arm-kernel/msg175729.html
    
      The last patch merges changes from both updates and provides a
      resolution for the conflicts which cannot be avoided when patches have
      been applied on the same files (mainly arch/arm/mm/dma-mapping.c)."
    
    Acked by Andrew Morton <akpm@linux-foundation.org>:
     "Yup, this one please.  It's had much work, plenty of review and I
      think even Russell is happy with it."
    
    * 'for-linus' of git://git.linaro.org/people/mszyprowski/linux-dma-mapping: (28 commits)
      ARM: dma-mapping: use PMD size for section unmap
      cma: fix migration mode
      ARM: integrate CMA with DMA-mapping subsystem
      X86: integrate CMA with DMA-mapping subsystem
      drivers: add Contiguous Memory Allocator
      mm: trigger page reclaim in alloc_contig_range() to stabilise watermarks
      mm: extract reclaim code from __alloc_pages_direct_reclaim()
      mm: Serialize access to min_free_kbytes
      mm: page_isolation: MIGRATE_CMA isolation functions added
      mm: mmzone: MIGRATE_CMA migration type added
      mm: page_alloc: change fallbacks array handling
      mm: page_alloc: introduce alloc_contig_range()
      mm: compaction: export some of the functions
      mm: compaction: introduce isolate_freepages_range()
      mm: compaction: introduce map_pages()
      mm: compaction: introduce isolate_migratepages_range()
      mm: page_alloc: remove trailing whitespace
      ARM: dma-mapping: add support for IOMMU mapper
      ARM: dma-mapping: use alloc, mmap, free from dma_ops
      ARM: dma-mapping: remove redundant code and do the cleanup
      ...
    
    Conflicts:
    	arch/x86/include/asm/dma-mapping.h
    d484864d
Kconfig 64.7 KB