Message ID | 20230322092118.9213-1-paul@crapouillou.net (mailing list archive) |
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Received: from vger.kernel.org ([23.128.96.18]) by www.linuxtv.org with esmtp (Exim 4.92) (envelope-from <linux-media-owner@vger.kernel.org>) id 1peutP-004yHM-EA; Wed, 22 Mar 2023 09:36:27 +0000 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230479AbjCVJgZ (ORCPT <rfc822;mkrufky@linuxtv.org> + 1 other); Wed, 22 Mar 2023 05:36:25 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37136 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230461AbjCVJgX (ORCPT <rfc822;linux-media@vger.kernel.org>); Wed, 22 Mar 2023 05:36:23 -0400 Received: from aposti.net (aposti.net [89.234.176.197]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7251E5F529; Wed, 22 Mar 2023 02:36:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=crapouillou.net; s=mail; t=1679476886; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=tmRlYhR2FZnlnQJCWKDJjWOgiCSSl9pc0u4cFJUJ650=; b=N+K9gfMWBsR4tD4u3Hl8NNLbTta8iPSN0ERcGscwa47kxMOGN0UFmiTqCEo0xcvmKjCd74 5QKS+X1c2izruTxdi+aR2/bxOzM5vWFMvFs5pp/4TwXtEn6OYJKWv7KKZgoXYHILsy+BHa 2AW0NIB2KkWH3t1e96o1srWamY7k2XM= From: Paul Cercueil <paul@crapouillou.net> To: Greg Kroah-Hartman <gregkh@linuxfoundation.org>, Sumit Semwal <sumit.semwal@linaro.org>, =?utf-8?q?Christian_K=C3=B6nig?= <christian.koenig@amd.com> Cc: michael.hennerich@analog.com, nuno.sa@analog.com, linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org, Paul Cercueil <paul@crapouillou.net> Subject: [PATCH v2 0/3] usb: gadget: functionfs: DMABUF import interface Date: Wed, 22 Mar 2023 10:21:15 +0100 Message-Id: <20230322092118.9213-1-paul@crapouillou.net> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Spam-Status: No, score=-0.2 required=5.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,DKIM_VALID_EF,SPF_HELO_PASS,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: <linux-media.vger.kernel.org> X-Mailing-List: linux-media@vger.kernel.org X-LSpam-Score: -2.5 (--) X-LSpam-Report: No, score=-2.5 required=5.0 tests=BAYES_00=-1.9,DKIM_SIGNED=0.1,DKIM_VALID=-0.1,DKIM_VALID_AU=-0.1,HEADER_FROM_DIFFERENT_DOMAINS=0.5,MAILING_LIST_MULTI=-1 autolearn=ham autolearn_force=no |
Series |
usb: gadget: functionfs: DMABUF import interface
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Message
Paul Cercueil
March 22, 2023, 9:21 a.m. UTC
Hi, This small patchset adds three new IOCTLs that can be used to attach, detach, or transfer from/to a DMABUF object. Changes since v1: - patch [2/3] is new. I had to reuse a piece of code that was already duplicated in the driver, so I factorized the code. - Make ffs_dma_resv_lock() static - Add MODULE_IMPORT_NS(DMA_BUF); - The attach/detach functions are now performed without locking the eps_lock spinlock. The transfer function starts with the spinlock unlocked, then locks it before allocating and queueing the USB transfer. Cheers, -Paul Paul Cercueil (3): usb: gadget: Support already-mapped DMA SGs usb: gadget: functionfs: Factorize wait-for-endpoint code usb: gadget: functionfs: Add DMABUF import interface drivers/usb/gadget/function/f_fs.c | 467 ++++++++++++++++++++++++++-- drivers/usb/gadget/udc/core.c | 7 +- include/linux/usb/gadget.h | 2 + include/uapi/linux/usb/functionfs.h | 14 +- 4 files changed, 468 insertions(+), 22 deletions(-)
Comments
Hi Paul, W dniu 22.03.2023 o 10:21, Paul Cercueil pisze: > Hi, > > This small patchset adds three new IOCTLs that can be used to attach, > detach, or transfer from/to a DMABUF object. > > Changes since v1: > - patch [2/3] is new. I had to reuse a piece of code that was already > duplicated in the driver, so I factorized the code. > - Make ffs_dma_resv_lock() static > - Add MODULE_IMPORT_NS(DMA_BUF); > - The attach/detach functions are now performed without locking the > eps_lock spinlock. The transfer function starts with the spinlock > unlocked, then locks it before allocating and queueing the USB > transfer. > Can you share an example use case for these new features? Is there a userspace that excercises the new ioctls? Regards, Andrzej
Hi Andrzej, Le vendredi 31 mars 2023 à 11:40 +0200, Andrzej Pietrasiewicz a écrit : > Hi Paul, > > W dniu 22.03.2023 o 10:21, Paul Cercueil pisze: > > Hi, > > > > This small patchset adds three new IOCTLs that can be used to > > attach, > > detach, or transfer from/to a DMABUF object. > > > > Changes since v1: > > - patch [2/3] is new. I had to reuse a piece of code that was > > already > > duplicated in the driver, so I factorized the code. > > - Make ffs_dma_resv_lock() static > > - Add MODULE_IMPORT_NS(DMA_BUF); > > - The attach/detach functions are now performed without locking the > > eps_lock spinlock. The transfer function starts with the > > spinlock > > unlocked, then locks it before allocating and queueing the USB > > transfer. > > > > Can you share an example use case for these new features? > Is there a userspace that excercises the new ioctls? We use it at Analog Devices to share buffers between the IIO subsystem and the USB stack, which makes it possible to stream data samples between a host computer and high-speed transceivers as fast as possible, in a zero-copy fashion. This will be used by Libiio: https://github.com/analogdevicesinc/libiio/pull/928/commits/dd348137ce371532fd952a2b249cfd96afaef7d1 The code that uses these IOCTLs is not yet merged to the "master" branch, but will be as soon as this patchset is accepted. Cheers, -Paul