Re: [RESEND][PATCH v8 4/5] dma-buf: heaps: Add CMA heap to dmabuf heaps

On Mon, Sep 30, 2019 at 1:14 AM Hillf Danton hdanton@sina.com wrote:

On Fri, 6 Sep 2019 18:47:09 +0000 John Stultz wrote:

...

• cma_pages = cma_alloc(cma_heap->cma, nr_pages, align, false);
  

• if (!cma_pages)
  

•         goto free_buf;
  

• if (PageHighMem(cma_pages)) {
  

•         unsigned long nr_clear_pages = nr_pages;
  

•         struct page *page = cma_pages;
  

•         while (nr_clear_pages > 0) {
  

•                 void *vaddr = kmap_atomic(page);
  

•                 memset(vaddr, 0, PAGE_SIZE);
  

•                 kunmap_atomic(vaddr);
  

•                 page++;
  

•                 nr_clear_pages--;
  

•         }
  

• } else {
  

•         memset(page_address(cma_pages), 0, size);
  

• }
  

Take a breath after zeroing a page, and a peep at pending signal.

Ok. Took a swing at this. It will be in the next revision.

Thanks again for the review! -john