On 20/07/17 11:19, Vladimir Murzin wrote: > The way how default DMA pool is exposed has changed and now we need to > use dedicated interface to work with it. This patch makes alloc/release > operations to use such interface. Since, default DMA pool is not > handled by generic code anymore we have to implement our own mmap > operation. > > Tested-by: Andras Szemzo <[email protected]> > Signed-off-by: Vladimir Murzin <[email protected]>
Looks like the right thing to do :) Reviewed-by: Robin Murphy <[email protected]> > --- > arch/arm/mm/dma-mapping-nommu.c | 45 > ++++++++++++++++++++++++++++++++--------- > 1 file changed, 36 insertions(+), 9 deletions(-) > > diff --git a/arch/arm/mm/dma-mapping-nommu.c b/arch/arm/mm/dma-mapping-nommu.c > index 90ee354..6db5fc2 100644 > --- a/arch/arm/mm/dma-mapping-nommu.c > +++ b/arch/arm/mm/dma-mapping-nommu.c > @@ -40,9 +40,21 @@ static void *arm_nommu_dma_alloc(struct device *dev, > size_t size, > > { > const struct dma_map_ops *ops = &dma_noop_ops; > + void *ret; > > /* > - * We are here because: > + * Try generic allocator first if we are advertised that > + * consistency is not required. > + */ > + > + if (attrs & DMA_ATTR_NON_CONSISTENT) > + return ops->alloc(dev, size, dma_handle, gfp, attrs); > + > + ret = dma_alloc_from_global_coherent(size, dma_handle); > + > + /* > + * dma_alloc_from_global_coherent() may fail because: > + * > * - no consistent DMA region has been defined, so we can't > * continue. > * - there is no space left in consistent DMA region, so we > @@ -50,11 +62,8 @@ static void *arm_nommu_dma_alloc(struct device *dev, > size_t size, > * advertised that consistency is not required. > */ > > - if (attrs & DMA_ATTR_NON_CONSISTENT) > - return ops->alloc(dev, size, dma_handle, gfp, attrs); > - > - WARN_ON_ONCE(1); > - return NULL; > + WARN_ON_ONCE(ret == NULL); > + return ret; > } > > static void arm_nommu_dma_free(struct device *dev, size_t size, > @@ -63,14 +72,31 @@ static void arm_nommu_dma_free(struct device *dev, size_t > size, > { > const struct dma_map_ops *ops = &dma_noop_ops; > > - if (attrs & DMA_ATTR_NON_CONSISTENT) > + if (attrs & DMA_ATTR_NON_CONSISTENT) { > ops->free(dev, size, cpu_addr, dma_addr, attrs); > - else > - WARN_ON_ONCE(1); > + } else { > + int ret = dma_release_from_global_coherent(get_order(size), > + cpu_addr); > + > + WARN_ON_ONCE(ret == 0); > + } > > return; > } > > +static int arm_nommu_dma_mmap(struct device *dev, struct vm_area_struct *vma, > + void *cpu_addr, dma_addr_t dma_addr, size_t size, > + unsigned long attrs) > +{ > + int ret; > + > + if (dma_mmap_from_global_coherent(vma, cpu_addr, size, &ret)) > + return ret; > + > + return dma_common_mmap(dev, vma, cpu_addr, dma_addr, size); > +} > + > + > static void __dma_page_cpu_to_dev(phys_addr_t paddr, size_t size, > enum dma_data_direction dir) > { > @@ -173,6 +199,7 @@ static void arm_nommu_dma_sync_sg_for_cpu(struct device > *dev, struct scatterlist > const struct dma_map_ops arm_nommu_dma_ops = { > .alloc = arm_nommu_dma_alloc, > .free = arm_nommu_dma_free, > + .mmap = arm_nommu_dma_mmap, > .map_page = arm_nommu_dma_map_page, > .unmap_page = arm_nommu_dma_unmap_page, > .map_sg = arm_nommu_dma_map_sg, >
