Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754226AbaKQODj (ORCPT ); Mon, 17 Nov 2014 09:03:39 -0500 Received: from down.free-electrons.com ([37.187.137.238]:48964 "EHLO mail.free-electrons.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752781AbaKQNpG (ORCPT ); Mon, 17 Nov 2014 08:45:06 -0500 From: Maxime Ripard To: Vinod Koul , dmaengine@vger.kernel.org Cc: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Laurent Pinchart , =?UTF-8?q?Antoine=20T=C3=A9nart?= , Russell King , lars@metafoo.de, Maxime Ripard Subject: [PATCH v5 04/61] dmaengine: Rework dma_chan_get Date: Mon, 17 Nov 2014 14:41:58 +0100 Message-Id: <1416231775-31252-5-git-send-email-maxime.ripard@free-electrons.com> X-Mailer: git-send-email 2.1.1 In-Reply-To: <1416231775-31252-1-git-send-email-maxime.ripard@free-electrons.com> References: <1416231775-31252-1-git-send-email-maxime.ripard@free-electrons.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org dma_chan_get uses a rather interesting error handling and code path. Change it to something more usual in the kernel. Signed-off-by: Maxime Ripard Acked-by: Laurent Pinchart --- drivers/dma/dmaengine.c | 36 +++++++++++++++++++----------------- 1 file changed, 19 insertions(+), 17 deletions(-) diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c index 24bfaf0b92ba..72f10e2f5c32 100644 --- a/drivers/dma/dmaengine.c +++ b/drivers/dma/dmaengine.c @@ -222,31 +222,33 @@ static void balance_ref_count(struct dma_chan *chan) */ static int dma_chan_get(struct dma_chan *chan) { - int err = -ENODEV; struct module *owner = dma_chan_to_owner(chan); + int ret; + /* The channel is already in use, update client count */ if (chan->client_count) { __module_get(owner); - err = 0; - } else if (try_module_get(owner)) - err = 0; + goto out; + } - if (err == 0) - chan->client_count++; + if (!try_module_get(owner)) + return -ENODEV; /* allocate upon first client reference */ - if (chan->client_count == 1 && err == 0) { - int desc_cnt = chan->device->device_alloc_chan_resources(chan); - - if (desc_cnt < 0) { - err = desc_cnt; - chan->client_count = 0; - module_put(owner); - } else if (!dma_has_cap(DMA_PRIVATE, chan->device->cap_mask)) - balance_ref_count(chan); - } + ret = chan->device->device_alloc_chan_resources(chan); + if (ret < 0) + goto err_out; - return err; + if (!dma_has_cap(DMA_PRIVATE, chan->device->cap_mask)) + balance_ref_count(chan); + +out: + chan->client_count++; + return 0; + +err_out: + module_put(owner); + return ret; } /** -- 2.1.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/