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Wed, 2 Apr 2025 19:36:17 +0000 Message-ID: <49b8b758-2d72-4de9-b0f1-dbf9a7124cdf@talpey.com> Date: Wed, 2 Apr 2025 15:36:15 -0400 User-Agent: Mozilla Thunderbird Subject: Re: cifs RDMA restrictions To: David Howells Cc: Steve French , Steve French , Stefan Metzmacher , Paulo Alcantara , Matthew Wilcox , CIFS References: <78c910b0-3391-484e-aa44-42e2f9ff4637@talpey.com> <563557.1743526559@warthog.procyon.org.uk> <659109.1743536087@warthog.procyon.org.uk> <7e1fc71c-2821-4294-833c-746c5fd7ee69@talpey.com> <803441.1743613785@warthog.procyon.org.uk> <843601.1743622017@warthog.procyon.org.uk> Content-Language: en-US From: Tom Talpey In-Reply-To: <843601.1743622017@warthog.procyon.org.uk> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-ClientProxiedBy: BN9PR03CA0305.namprd03.prod.outlook.com (2603:10b6:408:112::10) To SN6PR01MB3854.prod.exchangelabs.com (2603:10b6:805:19::20) Precedence: bulk X-Mailing-List: linux-cifs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: SN6PR01MB3854:EE_|DS0PR01MB7890:EE_ X-MS-Office365-Filtering-Correlation-Id: 352e216e-8bcb-4085-e50e-08dd721da363 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|376014|366016|1800799024; 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I guess so. That code has been there all long and I haven't looked into changing it. The comment at the top certainly says it's something to consider. The SMB Direct reassembly stuff is the non-RDMA path, where a message payload is too large for a single ~1KB datagram, but was not registered for direct placement. This would mainly be fsctl's and small reads. I wouldn't get too worked up about highly optimizing those. Tom.