From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.13]) (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 086C74C6C; Mon, 28 Oct 2024 02:01:09 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.13 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730080872; cv=none; b=EljFwNStEK1a9jF9olcr8EuC2x6PSr9+hoPH/MEYK6RdkMP1HQKCQr30SLPOpqb3IF29dKlLTq4hEJti2K4P0mDrSBoyQwUXvXxpufu4FWzvUOrmZ+z4RBh6L+TbiW1MyByJxtmKA6CMNJJJxSdq4q69NHuV7TGmW9f1MOTmNCs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730080872; c=relaxed/simple; bh=O3Ovtbf3MrmDzHqqK2oXEfGTFDsY4Dl/uMRNNzQ0jlU=; h=Message-ID:Date:MIME-Version:Cc:Subject:To:References:From: In-Reply-To:Content-Type; b=NHTFbKDZlCpS/mOegY+6MSe+a2RlkVGVBRLp582Z0qGmss3m7YcE7jLCe6AFgXBRIlOOdIW7fSSzSomjASh7HATQ1XNaKPVlPGVXLlzDJiB/56cQ8vwILwAG3usEE7Evq4cy+/7b/+zDq077HqzxTrp2hzkJB3pyApSHJW1z7uQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com; spf=none smtp.mailfrom=linux.intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=FEAgzFUH; arc=none smtp.client-ip=192.198.163.13 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="FEAgzFUH" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1730080870; x=1761616870; h=message-id:date:mime-version:cc:subject:to:references: from:in-reply-to:content-transfer-encoding; bh=O3Ovtbf3MrmDzHqqK2oXEfGTFDsY4Dl/uMRNNzQ0jlU=; b=FEAgzFUHr3EQeuWhjCD3MszQyI86wPqnDx/ufKLi4m/0yXVv62m/0PdX Qb34JnriCtA7T64jegh2/b/ygqDorvKBw2ODy6ltR+yqCqlfmerDhpNG1 DLqJIUQtzk1ueG0x9u1ZglHJWfAjIAgEiQVV7L2ZsCwCXcsn7qmMBN2ib caBi6uRteHLVW07jY7GM7ol+1yuZlXtzwshj0qfK7XQB45iur85AwtdZm QFnHEdXxT5aINA4SqwEKL2oEeueg/ApaXiXrTga0JvE74MDtu34m/QmM5 gxaVbagNjoFTDRRaDpL1fsWSi2xAaK40GBg8JHWj7z597sKNXq5ehYJtH A==; X-CSE-ConnectionGUID: GUE7Y+dvRjSSYU6F1TMxbw== X-CSE-MsgGUID: NYnuvrPVSNiuuMueSjJUfQ== X-IronPort-AV: E=McAfee;i="6700,10204,11238"; a="32530610" X-IronPort-AV: E=Sophos;i="6.11,238,1725346800"; d="scan'208";a="32530610" Received: from fmviesa002.fm.intel.com ([10.60.135.142]) by fmvoesa107.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 27 Oct 2024 19:01:09 -0700 X-CSE-ConnectionGUID: qpBwISFYS46tXapmQ++WeA== X-CSE-MsgGUID: cTaC7appS+WESSNDD4yrMw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.11,238,1725346800"; d="scan'208";a="104792722" Received: from blu2-mobl.ccr.corp.intel.com (HELO [10.238.0.51]) ([10.238.0.51]) by fmviesa002-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 27 Oct 2024 19:00:28 -0700 Message-ID: <6a9366a5-7c5b-449c-b259-8e2492aae2a1@linux.intel.com> Date: Mon, 28 Oct 2024 10:00:25 +0800 Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Cc: baolu.lu@linux.intel.com, Leon Romanovsky , Keith Busch , Bjorn Helgaas , Logan Gunthorpe , Yishai Hadas , Shameer Kolothum , Kevin Tian , Alex Williamson , Marek Szyprowski , =?UTF-8?B?SsOpcsO0bWUgR2xpc3Nl?= , Andrew Morton , Jonathan Corbet , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-block@vger.kernel.org, linux-rdma@vger.kernel.org, iommu@lists.linux.dev, linux-nvme@lists.infradead.org, linux-pci@vger.kernel.org, kvm@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH 07/18] dma-mapping: Implement link/unlink ranges API To: Leon Romanovsky , Jens Axboe , Jason Gunthorpe , Robin Murphy , Joerg Roedel , Will Deacon , Christoph Hellwig , Sagi Grimberg References: Content-Language: en-US From: Baolu Lu In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 2024/10/27 22:21, Leon Romanovsky wrote: > +/** > + * dma_iova_sync - Sync IOTLB > + * @dev: DMA device > + * @state: IOVA state > + * @offset: offset into the IOVA state to sync > + * @size: size of the buffer > + * @ret: return value from the last IOVA operation > + * > + * Sync IOTLB for the given IOVA state. This function should be called on > + * the IOVA-contigous range created by one ore more dma_iova_link() calls > + * to sync the IOTLB. > + */ > +int dma_iova_sync(struct device *dev, struct dma_iova_state *state, > + size_t offset, size_t size, int ret) > +{ > + struct iommu_domain *domain = iommu_get_dma_domain(dev); > + struct iommu_dma_cookie *cookie = domain->iova_cookie; > + struct iova_domain *iovad = &cookie->iovad; > + dma_addr_t addr = state->addr + offset; > + size_t iova_start_pad = iova_offset(iovad, addr); > + > + addr -= iova_start_pad; > + size = iova_align(iovad, size + iova_start_pad); > + > + if (!ret) > + ret = iommu_sync_map(domain, addr, size); > + if (ret) > + iommu_unmap(domain, addr, size); It appears strange that mapping is not done in this helper, but unmapping is added in the failure path. Perhaps I overlooked anything? To my understanding, it should like below: return iommu_sync_map(domain, addr, size); In the drivers that make use of this interface should do something like below: ret = dma_iova_sync(...); if (ret) dma_iova_destroy(...) > + return ret; > +} > +EXPORT_SYMBOL_GPL(dma_iova_sync); Thanks, baolu