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author | Tony Lindgren <tony@atomide.com> | 2010-08-04 14:43:45 +0300 |
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committer | Tony Lindgren <tony@atomide.com> | 2010-08-04 14:43:45 +0300 |
commit | 7590d1defdc720a97a9e186f45f529c4ae1b40f7 (patch) | |
tree | e7ffdc043a2847f410d654d8e99e001f3138937a /arch/arm/mm/dma-mapping.c | |
parent | 7e788b4289bb025a96e327c604cb2db92e17108f (diff) | |
parent | 869fef41547db95df8523bf67845a21313709428 (diff) | |
download | op-kernel-dev-7590d1defdc720a97a9e186f45f529c4ae1b40f7.zip op-kernel-dev-7590d1defdc720a97a9e186f45f529c4ae1b40f7.tar.gz |
Merge branch 'devel-map-io' into omap-for-linus
Diffstat (limited to 'arch/arm/mm/dma-mapping.c')
-rw-r--r-- | arch/arm/mm/dma-mapping.c | 15 |
1 files changed, 14 insertions, 1 deletions
diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c index 9e7742f..c704eed 100644 --- a/arch/arm/mm/dma-mapping.c +++ b/arch/arm/mm/dma-mapping.c @@ -183,6 +183,8 @@ static void * __dma_alloc_remap(struct page *page, size_t size, gfp_t gfp, pgprot_t prot) { struct arm_vmregion *c; + size_t align; + int bit; if (!consistent_pte[0]) { printk(KERN_ERR "%s: not initialised\n", __func__); @@ -191,9 +193,20 @@ __dma_alloc_remap(struct page *page, size_t size, gfp_t gfp, pgprot_t prot) } /* + * Align the virtual region allocation - maximum alignment is + * a section size, minimum is a page size. This helps reduce + * fragmentation of the DMA space, and also prevents allocations + * smaller than a section from crossing a section boundary. + */ + bit = fls(size - 1) + 1; + if (bit > SECTION_SHIFT) + bit = SECTION_SHIFT; + align = 1 << bit; + + /* * Allocate a virtual address in the consistent mapping region. */ - c = arm_vmregion_alloc(&consistent_head, size, + c = arm_vmregion_alloc(&consistent_head, align, size, gfp & ~(__GFP_DMA | __GFP_HIGHMEM)); if (c) { pte_t *pte; |