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authorLinus Torvalds <torvalds@linux-foundation.org>2012-05-25 20:18:59 +0400
committerLinus Torvalds <torvalds@linux-foundation.org>2012-05-25 20:18:59 +0400
commitd484864dd96e1830e7689510597707c1df8cd681 (patch)
tree51551708ba3f26d05575fa91daaf0c0d970a77c3 /Documentation/kernel-parameters.txt
parentbe87cfb47c5c740f7b17929bcd7c480b228513e0 (diff)
parent0f51596bd39a5c928307ffcffc9ba07f90f42a8b (diff)
downloadlinux-d484864dd96e1830e7689510597707c1df8cd681.tar.xz
Merge branch 'for-linus' of git://git.linaro.org/people/mszyprowski/linux-dma-mapping
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
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diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index b69cfdc12112..f1959b7d13d0 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -508,6 +508,11 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
Also note the kernel might malfunction if you disable
some critical bits.
+ cma=nn[MG] [ARM,KNL]
+ Sets the size of kernel global memory area for contiguous
+ memory allocations. For more information, see
+ include/linux/dma-contiguous.h
+
cmo_free_hint= [PPC] Format: { yes | no }
Specify whether pages are marked as being inactive
when they are freed. This is used in CMO environments
@@ -515,6 +520,10 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
a hypervisor.
Default: yes
+ coherent_pool=nn[KMG] [ARM,KNL]
+ Sets the size of memory pool for coherent, atomic dma
+ allocations if Contiguous Memory Allocator (CMA) is used.
+
code_bytes [X86] How many bytes of object code to print
in an oops report.
Range: 0 - 8192