From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pb0-f42.google.com (mail-pb0-f42.google.com [209.85.160.42]) by kanga.kvack.org (Postfix) with ESMTP id 168ED6B0031 for ; Mon, 16 Jun 2014 01:15:42 -0400 (EDT) Received: by mail-pb0-f42.google.com with SMTP id ma3so3800599pbc.15 for ; Sun, 15 Jun 2014 22:15:41 -0700 (PDT) Received: from lgeamrelo04.lge.com (lgeamrelo04.lge.com. [156.147.1.127]) by mx.google.com with ESMTP id rq2si9641397pbc.163.2014.06.15.22.15.40 for ; Sun, 15 Jun 2014 22:15:41 -0700 (PDT) Date: Mon, 16 Jun 2014 14:19:52 +0900 From: Joonsoo Kim Subject: Re: [PATCH v2 04/10] DMA, CMA: support alignment constraint on cma region Message-ID: <20140616051952.GB23210@js1304-P5Q-DELUXE> References: <1402543307-29800-1-git-send-email-iamjoonsoo.kim@lge.com> <1402543307-29800-5-git-send-email-iamjoonsoo.kim@lge.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: Sender: owner-linux-mm@kvack.org List-ID: To: Michal Nazarewicz Cc: Andrew Morton , "Aneesh Kumar K.V" , Marek Szyprowski , Minchan Kim , Russell King - ARM Linux , Greg Kroah-Hartman , Paolo Bonzini , Gleb Natapov , Alexander Graf , Benjamin Herrenschmidt , Paul Mackerras , linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvm@vger.kernel.org, kvm-ppc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org On Thu, Jun 12, 2014 at 12:02:38PM +0200, Michal Nazarewicz wrote: > On Thu, Jun 12 2014, Joonsoo Kim wrote: > > ppc kvm's cma area management needs alignment constraint on > > I've noticed it earlier and cannot seem to get to terms with this. It > should IMO be PPC, KVM and CMA since those are acronyms. But if you > have strong feelings, it's not a big issue. Yes, I will fix it. > > > cma region. So support it to prepare generalization of cma area > > management functionality. > > > > Additionally, add some comments which tell us why alignment > > constraint is needed on cma region. > > > > Signed-off-by: Joonsoo Kim > > Acked-by: Michal Nazarewicz > > > diff --git a/drivers/base/dma-contiguous.c b/drivers/base/dma-contiguous.c > > index 8a44c82..bc4c171 100644 > > --- a/drivers/base/dma-contiguous.c > > +++ b/drivers/base/dma-contiguous.c > > @@ -219,6 +220,7 @@ core_initcall(cma_init_reserved_areas); > > * @size: Size of the reserved area (in bytes), > > * @base: Base address of the reserved area optional, use 0 for any > > * @limit: End address of the reserved memory (optional, 0 for any). > > + * @alignment: Alignment for the contiguous memory area, should be > > power of 2 > > a??must be power of 2 or zeroa??. Okay. > > * @res_cma: Pointer to store the created cma region. > > * @fixed: hint about where to place the reserved area > > * > > @@ -233,15 +235,15 @@ core_initcall(cma_init_reserved_areas); > > */ > > static int __init __dma_contiguous_reserve_area(phys_addr_t size, > > phys_addr_t base, phys_addr_t limit, > > + phys_addr_t alignment, > > struct cma **res_cma, bool fixed) > > { > > struct cma *cma = &cma_areas[cma_area_count]; > > - phys_addr_t alignment; > > int ret = 0; > > > > - pr_debug("%s(size %lx, base %08lx, limit %08lx)\n", __func__, > > - (unsigned long)size, (unsigned long)base, > > - (unsigned long)limit); > > + pr_debug("%s(size %lx, base %08lx, limit %08lx align_order %08lx)\n", > > + __func__, (unsigned long)size, (unsigned long)base, > > + (unsigned long)limit, (unsigned long)alignment); > > Nit: Align with the rest of the arguments, i.e.: > > + pr_debug("%s(size %lx, base %08lx, limit %08lx align_order %08lx)\n", > + __func__, (unsigned long)size, (unsigned long)base, > + (unsigned long)limit, (unsigned long)alignment); What's the difference between mine and yours? Thanks. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org