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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id CFED5C433F5 for ; Thu, 14 Oct 2021 10:31:34 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 8FE4A610E6 for ; Thu, 14 Oct 2021 10:31:34 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 8FE4A610E6 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=mediatek.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:CC:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=W1+ZkjbWNEPieZYigLMr4ySvKfJy2Uw3OpDH2Ki0em0=; b=3CrGQbmUvPqNSR iqVPHIKcwSnoCiOGB6abGYTXNekKtwu9Wt6zPw+jEEmZg4uhHN9lXqG9Mj1PbskLJu193MkH0954V 8pWfIkxSI8227n6r9JFUlN6v8JQZ5upkJnFidYT3ybARKjlIItzCJnrw0k1jXDscCn1N6rAGxq9vY YNkTXzq34lqHMxYsiBAIaJRy//QH+DEszvQU8DWiiOMt53FEmXH/1+DFxUG8lpWWUNOsl8bkSnwGd x2RozAfmJagn0PXVzNplJpnHATDHwsh3iBAdaArGUp2Vde7LlbWXb+dTkaMgnOxAYyXxk/Y0Iiuq+ nDFM+KmPicSunSTBBFeg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1maxyv-002ZjO-91; Thu, 14 Oct 2021 10:29:02 +0000 Received: from mailgw02.mediatek.com ([216.200.240.185]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1maxw3-002YM9-F2; Thu, 14 Oct 2021 10:26:07 +0000 X-UUID: 9745472ceb864fd3b56aa82665f7b472-20211014 X-UUID: 9745472ceb864fd3b56aa82665f7b472-20211014 Received: from mtkcas66.mediatek.inc [(172.29.193.44)] by mailgw02.mediatek.com (envelope-from ) (musrelay.mediatek.com ESMTP with TLSv1.2 ECDHE-RSA-AES256-SHA384 256/256) with ESMTP id 1538313631; Thu, 14 Oct 2021 03:25:57 -0700 Received: from mtkmbs10n1.mediatek.inc (172.21.101.34) by MTKMBS62N1.mediatek.inc (172.29.193.41) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Thu, 14 Oct 2021 03:25:55 -0700 Received: from mtkcas11.mediatek.inc (172.21.101.40) by mtkmbs10n1.mediatek.inc (172.21.101.34) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384) id 15.2.792.15; Thu, 14 Oct 2021 18:25:54 +0800 Received: from mszswglt01.gcn.mediatek.inc (10.16.20.20) by mtkcas11.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1497.2 via Frontend Transport; Thu, 14 Oct 2021 18:25:53 +0800 From: To: , CC: , , , , , , , , , , Guangming Cao Subject: [PATCH v3] dma-buf: remove restriction of IOCTL:DMA_BUF_SET_NAME Date: Thu, 14 Oct 2021 18:25:51 +0800 Message-ID: <20211014102551.54983-1-guangming.cao@mediatek.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20211012084109.176542-1-guangming.cao@mediatek.com> References: <20211012084109.176542-1-guangming.cao@mediatek.com> MIME-Version: 1.0 X-MTK: N X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20211014_032603_515048_22F6F03C X-CRM114-Status: GOOD ( 17.43 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: Guangming Cao In this patch(https://patchwork.freedesktop.org/patch/310349), it add a new IOCTL to support dma-buf user to set debug name. But it also added a limitation of this IOCTL, it needs the attachments of dmabuf should be empty, otherwise it will fail. For the original series, the idea was that allowing name change mid-use could confuse the users about the dma-buf. However, the rest of the series also makes sure each dma-buf have a unique inode(https://patchwork.freedesktop.org/patch/310387/), and any accounting should probably use that, without relying on the name as much. So, removing this restriction will let dma-buf userspace users to use it more comfortably and without any side effect. Signed-off-by: Guangming Cao --- drivers/dma-buf/dma-buf.c | 17 +++-------------- 1 file changed, 3 insertions(+), 14 deletions(-) diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c index 511fe0d217a0..5fbb3a2068a3 100644 --- a/drivers/dma-buf/dma-buf.c +++ b/drivers/dma-buf/dma-buf.c @@ -325,10 +325,8 @@ static __poll_t dma_buf_poll(struct file *file, poll_table *poll) /** * dma_buf_set_name - Set a name to a specific dma_buf to track the usage. - * The name of the dma-buf buffer can only be set when the dma-buf is not - * attached to any devices. It could theoritically support changing the - * name of the dma-buf if the same piece of memory is used for multiple - * purpose between different devices. + * It could support changing the name of the dma-buf if the same + * piece of memory is used for multiple purpose between different devices. * * @dmabuf: [in] dmabuf buffer that will be renamed. * @buf: [in] A piece of userspace memory that contains the name of @@ -341,25 +339,16 @@ static __poll_t dma_buf_poll(struct file *file, poll_table *poll) static long dma_buf_set_name(struct dma_buf *dmabuf, const char __user *buf) { char *name = strndup_user(buf, DMA_BUF_NAME_LEN); - long ret = 0; if (IS_ERR(name)) return PTR_ERR(name); - dma_resv_lock(dmabuf->resv, NULL); - if (!list_empty(&dmabuf->attachments)) { - ret = -EBUSY; - kfree(name); - goto out_unlock; - } spin_lock(&dmabuf->name_lock); kfree(dmabuf->name); dmabuf->name = name; spin_unlock(&dmabuf->name_lock); -out_unlock: - dma_resv_unlock(dmabuf->resv); - return ret; + return 0; } static long dma_buf_ioctl(struct file *file, -- 2.17.1 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel