From patchwork Sat Aug 24 09:07:42 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zijun Hu X-Patchwork-Id: 13776389 Received: from pv50p00im-ztdg10021801.me.com (pv50p00im-ztdg10021801.me.com [17.58.6.56]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B4A101547C5 for ; Sat, 24 Aug 2024 09:08:14 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=17.58.6.56 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724490496; cv=none; b=CIu+bKVLx6Ki2Udvyyc0ni584B1HivrZtTGy8Bkp13gQS6LM97f+mfLSzAygcGjnWqjK+CZjubmECNvCTJpCyP0GDBCMPpXVoxxLMafc+mpiYz+g8Xz4rZQUDZ3OegR0YmaRw8mjjOW+qfzSTLgRa6v5ZQxMcvF4Vg3pdbe+mBE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724490496; c=relaxed/simple; bh=iDueYySTOYDf76dyKY+O2COXWFiJlDQMv8fu9IizmiA=; h=From:Subject:Date:Message-Id:MIME-Version:Content-Type:To:Cc; b=Y9mSioeyat+O4yb5o2yneTt+CI/13qAAS4Q47JdeVcE8ctJk2FNuwS5doDg9KYPceZambgz4NmsBsrRnHwcoaHHLV8kYR+AGyrAV8EYKPuKFOeUQPCoKmnoiVs6VpwNQvWYs8i0YxEdviJAS0YdC2SBkXOO2njPWh3q9s3Mmh9s= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=icloud.com; spf=pass smtp.mailfrom=icloud.com; dkim=pass (2048-bit key) header.d=icloud.com header.i=@icloud.com header.b=vBvAfaAI; arc=none smtp.client-ip=17.58.6.56 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=icloud.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=icloud.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=icloud.com header.i=@icloud.com header.b="vBvAfaAI" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=icloud.com; s=1a1hai; t=1724490494; bh=TzP6fFPiDxclLlxPva2OtcKn8MvNbhGsPMaB51w3/kI=; h=From:Subject:Date:Message-Id:MIME-Version:Content-Type:To; b=vBvAfaAIxGN1pnq2mQUXe0qKdUAMkx8vitOmUqcntV6DVfCcAOcHMAUUz9aOkdee5 fd9dNPRUOObQGLfTBG10GXeMGM68e1krza+hcWstHfvzFrmxgcuQGp4Cy/hBuCJVkS eO+WSmaxJnA7oClqX+XPf0YYT9vr0OObqisDBSkmn9P+I6Zkr0ditji9OxhZphuLdp BaoLq8Q+u5iwX11fdQVCvMX1KtNVmhvFyGbpFto/yL8tzvzDV3fVNKQMMlruLeMSiw XBqoA8VKztglPeuGFPywOQOm1bxwOarGfZ/uPM6YOs7dM7jUB+rR2gHPv0nLtIc00c IVe8Z1vMwYrMw== Received: from [192.168.1.26] (pv50p00im-dlb-asmtp-mailmevip.me.com [17.56.9.10]) by pv50p00im-ztdg10021801.me.com (Postfix) with ESMTPSA id B17D92010334; Sat, 24 Aug 2024 09:08:07 +0000 (UTC) From: Zijun Hu Subject: [PATCH v3 0/3] driver core: Prevent device_find_child() from modifying caller's match data Date: Sat, 24 Aug 2024 17:07:42 +0800 Message-Id: <20240824-const_dfc_prepare-v3-0-32127ea32bba@quicinc.com> Precedence: bulk X-Mailing-List: linux-cxl@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-B4-Tracking: v=1; b=H4sIAN6iyWYC/33NTQ6CMBQE4KuQrq2hLT+FlfcwhsBrK29hiy02G sLdLaw0MS5nkvlmIUF71IG02UK8jhjQ2RTEISMw9vaqKaqUCc95kUvGKDgb5k4Z6Cavp95rKoz hAqqykbokaZd6g8/dPF9SHjHMzr/2i8i29p8WGc2pqmqAglWDUOJ0fyCghSO4G9m8yD+N8pfBk yFF2st6kMY038a6rm+3ZjIw+AAAAA== To: Greg Kroah-Hartman , "Rafael J. Wysocki" , Davidlohr Bueso , Jonathan Cameron , Dave Jiang , Alison Schofield , Vishal Verma , Ira Weiny , Dan Williams , Takashi Sakamoto , Timur Tabi , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni Cc: Zijun Hu , linux-kernel@vger.kernel.org, linux-cxl@vger.kernel.org, netdev@vger.kernel.org, Zijun Hu X-Mailer: b4 0.14.1 X-Proofpoint-GUID: X7M2T8oCoMcwW3v59-FhLlvTphq15KTt X-Proofpoint-ORIG-GUID: X7M2T8oCoMcwW3v59-FhLlvTphq15KTt X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.272,Aquarius:18.0.1039,Hydra:6.0.680,FMLib:17.12.28.16 definitions=2024-08-24_08,2024-08-23_01,2024-05-17_01 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 malwarescore=0 suspectscore=0 mlxscore=0 mlxlogscore=999 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.19.0-2308100000 definitions=main-2408240053 X-Apple-Remote-Links: v=1;h=KCk=;charset=UTF-8 This patch series is to prepare for constifying the following driver API: struct device *device_find_child(struct device *dev, void *data, int (*match)(struct device *dev, void *data)); to struct device *device_find_child(struct device *dev, const void *data, int (*match)(struct device *dev, const void *data)); How to constify the API ? There are total 30 usages of the API in kernel tree: For 2/30 usages, the API's match function (*match)() will modify caller's match data @*data, and this patch series will clean up them. For remaining 28/30, the following patch series will simply change its relevant parameter type to const void *. https://lore.kernel.org/all/20240811-const_dfc_done-v1-1-9d85e3f943cb@quicinc.com/ Why to constify the API ? (1) It normally does not make sense, also does not need to, for such device finding operation to modify caller's match data which is mainly used for comparison. (2) It will make the API's match function and match data parameter have the same type as all other APIs (bus|class|driver)_find_device(). (3) It will give driver author hints about choice between this API and the following one: int device_for_each_child(struct device *dev, void *data, int (*fn)(struct device *dev, void *data)); Signed-off-by: Zijun Hu --- Changes in v3: - Git rebase - Correct commit message for the driver core patch - Use changes suggested by Ira Weiny cxl/region - Drop firewire core patch - Make qcom/emac follow cxl/region solution suggested by Greg - Link to v2: https://lore.kernel.org/r/20240815-const_dfc_prepare-v2-0-8316b87b8ff9@quicinc.com Changes in v2: - Give up introducing the API constify_device_find_child_helper() - Correct commit message and inline comments - Implement a driver specific and equivalent one instead of device_find_child() - Link to v1: https://lore.kernel.org/r/20240811-const_dfc_prepare-v1-0-d67cc416b3d3@quicinc.com --- Zijun Hu (3): driver core: Make parameter check consistent for API cluster device_(for_each|find)_child() cxl/region: Find free cxl decoder by device_for_each_child() net: qcom/emac: Prevent device_find_child() from modifying caller's match data drivers/base/core.c | 6 ++--- drivers/cxl/core/region.c | 30 ++++++++++++++++++++----- drivers/net/ethernet/qualcomm/emac/emac-sgmii.c | 22 +++++++++++++----- 3 files changed, 44 insertions(+), 14 deletions(-) --- base-commit: 888f67e621dda5c2804a696524e28d0ca4cf0a80 change-id: 20240811-const_dfc_prepare-3ff23c6598e5 Best regards,