From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.5 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id EB63CC43381 for ; Fri, 29 Mar 2019 16:02:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BB025218A2 for ; Fri, 29 Mar 2019 16:02:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1553875322; bh=hzmDGIrBrfjJp14dSLUxJEEtLN7tbFOqYWD83SmjARI=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=wZfm1KRAAIOynecZXerLg0ANKYxP1fovb2Oz8VX9beECk105z3opt8pZCikQY3uKp YkDZMvX+vXSfEpRmDS/XNba15ncocvDo1qujAWSDBwmy6R/NQ/RdLVHPhQDHInIo/c ZnDSRDTwNQGBweJ4p3l6R9130swH1/yonMHySuhg= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729786AbfC2QCB (ORCPT ); Fri, 29 Mar 2019 12:02:01 -0400 Received: from mail.kernel.org ([198.145.29.99]:50304 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728720AbfC2QCB (ORCPT ); Fri, 29 Mar 2019 12:02:01 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 478532070B; Fri, 29 Mar 2019 16:01:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1553875319; bh=hzmDGIrBrfjJp14dSLUxJEEtLN7tbFOqYWD83SmjARI=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=LNPwJNx8T3aXLynIaodBWnZvdUrjNnYAnJm4hA+H4EGTYKd9IBI5+w1Z6zqyt9Jak tdPvSpW94q/lDRxX6UDHl6aahM9l2Qw5k6BGUj5s6skNK3NVnS8ED9ArsWU/4LjCeN Z0LH37m1OKCOzad92IqFwvxZs/9Uer9EipUi96Rk= Date: Fri, 29 Mar 2019 17:01:57 +0100 From: Greg Kroah-Hartman To: Zeng Tao Cc: labbott@redhat.com, sumit.semwal@linaro.org, devel@driverdev.osuosl.org, Todd Kjos , linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org, Arve =?iso-8859-1?B?SGr4bm5lduVn?= , Joel Fernandes , Martijn Coenen , Christian Brauner Subject: Re: [PATCH] staging: android: ion: refactory ion_alloc for kernel driver use Message-ID: <20190329160157.GA5906@kroah.com> References: <1553884816-37850-1-git-send-email-prime.zeng@hisilicon.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1553884816-37850-1-git-send-email-prime.zeng@hisilicon.com> User-Agent: Mutt/1.11.4 (2019-03-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Mar 30, 2019 at 02:40:16AM +0800, Zeng Tao wrote: > There are two reasons for this patch: > 1. There are some potential requirements for ion_alloc in kernel space, > some media drivers need to allocate media buffers from ion instead of > buddy or dma framework, this is more convient and clean very for media > drivers. And In that case, ion is the only media buffer provider, it's > more easier to maintain. > 2. Fd is only needed by user processes, not the kernel space, so dma_buf > should be returned instead of fd for kernel space, and dma_buf_fd should > be called only for userspace api. > > Signed-off-by: Zeng Tao > --- > drivers/staging/android/ion/ion.c | 32 +++++++++++++++++--------------- > 1 file changed, 17 insertions(+), 15 deletions(-) > > diff --git a/drivers/staging/android/ion/ion.c b/drivers/staging/android/ion/ion.c > index 92c2914..e93fb49 100644 > --- a/drivers/staging/android/ion/ion.c > +++ b/drivers/staging/android/ion/ion.c > @@ -387,13 +387,13 @@ static const struct dma_buf_ops dma_buf_ops = { > .unmap = ion_dma_buf_kunmap, > }; > > -static int ion_alloc(size_t len, unsigned int heap_id_mask, unsigned int flags) > +struct dma_buf *ion_alloc(size_t len, unsigned int heap_id_mask, > + unsigned int flags) > { > struct ion_device *dev = internal_dev; > struct ion_buffer *buffer = NULL; > struct ion_heap *heap; > DEFINE_DMA_BUF_EXPORT_INFO(exp_info); > - int fd; > struct dma_buf *dmabuf; > > pr_debug("%s: len %zu heap_id_mask %u flags %x\n", __func__, > @@ -407,7 +407,7 @@ static int ion_alloc(size_t len, unsigned int heap_id_mask, unsigned int flags) > len = PAGE_ALIGN(len); > > if (!len) > - return -EINVAL; > + return ERR_PTR(-EINVAL); > > down_read(&dev->lock); > plist_for_each_entry(heap, &dev->heaps, node) { > @@ -421,10 +421,10 @@ static int ion_alloc(size_t len, unsigned int heap_id_mask, unsigned int flags) > up_read(&dev->lock); > > if (!buffer) > - return -ENODEV; > + return ERR_PTR(-ENODEV); > > if (IS_ERR(buffer)) > - return PTR_ERR(buffer); > + return ERR_PTR(PTR_ERR(buffer)); > > exp_info.ops = &dma_buf_ops; > exp_info.size = buffer->size; > @@ -432,17 +432,12 @@ static int ion_alloc(size_t len, unsigned int heap_id_mask, unsigned int flags) > exp_info.priv = buffer; > > dmabuf = dma_buf_export(&exp_info); > - if (IS_ERR(dmabuf)) { > + if (IS_ERR(dmabuf)) > _ion_buffer_destroy(buffer); > - return PTR_ERR(dmabuf); > - } > > - fd = dma_buf_fd(dmabuf, O_CLOEXEC); > - if (fd < 0) > - dma_buf_put(dmabuf); > - > - return fd; > + return dmabuf; > } > +EXPORT_SYMBOL(ion_alloc); If you are going to do this (and personally I'm with Laura in that I don't think you need it) this should be EXPORT_SYMBOL_GPL() please. thanks, greg k-h