From patchwork Thu Nov 17 22:07:55 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jacob Keller X-Patchwork-Id: 13047366 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 75D90C433FE for ; Thu, 17 Nov 2022 22:09:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240256AbiKQWI7 (ORCPT ); Thu, 17 Nov 2022 17:08:59 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46680 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241210AbiKQWIi (ORCPT ); Thu, 17 Nov 2022 17:08:38 -0500 Received: from mga14.intel.com (mga14.intel.com [192.55.52.115]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EE79656D76 for ; Thu, 17 Nov 2022 14:08:13 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1668722893; x=1700258893; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=1bCl+6ehL1vCwRa82jupCfnWFQYXFtLYyl1Fy6cnEiI=; b=HJoHwwK5I35u+kvs0GEBbsL4wgYgI35JrwGTm3mYyZQvI8OoW5W2mNwi pLikQJA18wbi2e7MTkX4NFF1l+gOtghyHKzZCO6YA3h1ZbHCnLWf6iSIu HOYE7weJxDMWAOZBzuc43hXF0yVG5zdC+E8oJaa44q3iCPIjiQEzF+wy2 AExwq7/SkSUqgnVe2KUVpSoJOnfIzkNI/10GcTNJslpWyKRYlEi7RFxeB U9pCnwLjZVWpRzumFKUELJ5JdP8Z/QcQ9FOa/iYrNOjUG7ziXc1f6nQ4w Ma7XAPQZP+ZFEe/QaN57BurCtH+bY5CBKHq4aRn5dOV/zdMLQcMp3AHM4 Q==; X-IronPort-AV: E=McAfee;i="6500,9779,10534"; a="313001214" X-IronPort-AV: E=Sophos;i="5.96,172,1665471600"; d="scan'208";a="313001214" Received: from orsmga001.jf.intel.com ([10.7.209.18]) by fmsmga103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 17 Nov 2022 14:08:13 -0800 X-IronPort-AV: E=McAfee;i="6500,9779,10534"; a="672975615" X-IronPort-AV: E=Sophos;i="5.96,172,1665471600"; d="scan'208";a="672975615" Received: from jekeller-desk.amr.corp.intel.com (HELO jekeller-desk.jekeller.internal) ([10.166.241.7]) by orsmga001-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 17 Nov 2022 14:08:12 -0800 From: Jacob Keller To: netdev@vger.kernel.org Cc: Jacob Keller , Jiri Pirko , Jakub Kicinski Subject: [PATCH net-next 0/8] devlink: support direct read from region Date: Thu, 17 Nov 2022 14:07:55 -0800 Message-Id: <20221117220803.2773887-1-jacob.e.keller@intel.com> X-Mailer: git-send-email 2.38.1.420.g319605f8f00e MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org A long time ago when initially implementing devlink regions in ice I proposed the ability to allow reading from a region without taking a snapshot [1]. I eventually dropped this work from the original series due to size. Then I eventually lost track of submitting this follow up. This can be useful when interacting with some region that has some definitive "contents" from which snapshots are made. For example the ice driver has regions representing the contents of the device flash. If userspace wants to read the contents today, it must first take a snapshot and then read from that snapshot. This makes sense if you want to read a large portion of data or you want to be sure reads are consistently from the same recording of the flash. However if user space only wants to read a small chunk, it must first generate a snapshot of the entire contents, perform a read from the snapshot, and then delete the snapshot after reading. For such a use case, a direct read from the region makes more sense. This can be achieved by allowing the devlink region read command to work without a snapshot. Instead the portion to be read can be forwarded directly to the driver via a new .read callback. This avoids the need to read the entire region contents into memory first and avoids the software overhead of creating a snapshot and then deleting it. This series implements such behavior and hooks up the ice NVM and shadow RAM regions to allow it. [1] https://lore.kernel.org/netdev/20200130225913.1671982-1-jacob.e.keller@intel.com/ Cc: Jiri Pirko Cc: Jakub Kicinski Jacob Keller (8): devlink: find snapshot in devlink_nl_cmd_region_read_dumpit devlink: use min_t to calculate data_size devlink: report extended error message in region_read_dumpit devlink: remove unnecessary parameter from chunk_fill function devlink: refactor region_read_snapshot_fill to use a callback function devlink: support directly reading from region memory ice: use same function to snapshot both NVM and Shadow RAM ice: implement direct read for NVM and Shadow RAM regions .../networking/devlink/devlink-region.rst | 8 ++ drivers/net/ethernet/intel/ice/ice_devlink.c | 112 +++++++++------- include/net/devlink.h | 16 +++ net/core/devlink.c | 121 +++++++++++++----- 4 files changed, 180 insertions(+), 77 deletions(-) base-commit: b4b221bd79a1c698d9653e3ae2c3cb61cdc9aee7