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Thu, 30 Nov 2023 00:18:43 +0900 (KST) Received: from [107.122.11.51] (unknown [107.122.11.51]) by epsmtip1.samsung.com (KnoxPortal) with ESMTPA id 20231129151842epsmtip1126d0a3df825a035a24bb43f22f1e340~cIRJ-p-DB0302803028epsmtip1f; Wed, 29 Nov 2023 15:18:42 +0000 (GMT) Message-ID: <249c59bb-794b-f8ec-c4e7-17308ecf7f2a@samsung.com> Date: Wed, 29 Nov 2023 20:48:41 +0530 Precedence: bulk X-Mailing-List: io-uring@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.8.1 Subject: Re: [PATCHv4 1/4] block: bio-integrity: directly map user buffers Content-Language: en-US To: Keith Busch , linux-block@vger.kernel.org, linux-nvme@lists.infradead.org, io-uring@vger.kernel.org Cc: axboe@kernel.dk, hch@lst.de, martin.petersen@oracle.com, ming.lei@redhat.com, Keith Busch From: Kanchan Joshi In-Reply-To: <20231128222752.1767344-2-kbusch@meta.com> Content-Transfer-Encoding: 7bit X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFlrDJsWRmVeSWpSXmKPExsWy7bCmpm5IWHqqwbM+DYvVd/vZLFauPspk 8a71HIvFpEPXGC3OXF3IYrH3lrbF/GVP2S2WH//HZHFocjOTA6fH5bOlHptWdbJ5bF5S77H7 ZgObx7mLFR4fn95i8Xi/7yqbx+dNcgEcUdk2GamJKalFCql5yfkpmXnptkrewfHO8aZmBoa6 hpYW5koKeYm5qbZKLj4Bum6ZOUC3KSmUJeaUAoUCEouLlfTtbIryS0tSFTLyi0tslVILUnIK TAr0ihNzi0vz0vXyUkusDA0MjEyBChOyM26t28tcsI25onPHc6YGxntMXYwcHBICJhI7dtd2 MXJxCAnsZpQ4NWstE4TziVFi+9L/LBDON0aJHx3vGbsYOcE6PnT9ZYVI7AVKtO+DannLKLHg 0m2wubwCdhK7L7iDNLAIqEr0nfrADGLzCghKnJz5hAXEFhVIkvh1dQ7YUGEBL4nnWxaBxZkF xCVuPZnPBGKLCFRJ9E37yQYRL5a437GbFWQ8m4CmxIXJpSAmp4C5xNfWYogKeYntb+cwg1wj IbCSQ+L65TVQN7tIPPh9jhXCFpZ4dXwLO4QtJfGyvw3KTpa4NPMcE4RdIvF4z0Eo216i9VQ/ M8guZqC163fpQ+zik+j9/QQaiLwSHW1CENWKEvcmPYXaJC7xcMYSVogSD4krW+wg4bSdUeLB hLNMExgVZiGFySwkv89C8s0shMULGFlWMUqmFhTnpqcWmxYY56WWwyM7OT93EyM42Wp572B8 9OCD3iFGJg7GQ4wSHMxKIrx6H5NThXhTEiurUovy44tKc1KLDzGaAiNnIrOUaHI+MN3nlcQb mlgamJiZmZlYGpsZKonzvm6dmyIkkJ5YkpqdmlqQWgTTx8TBKdXA5J/yZoHb/ISG8r7c33fy LaMXXPHibbVTnFxU3J9o+fyOWI7WgS/fdsrcYnztFHFW8F3wAQfXQ877PkadrdbxZrz4NOHV sjp/7bBr8+pfXWer+2s9xdDFUfHLo2XOnxPmTDhzKULQs+ioa3VocurxZ30hLdvYmDjspDYr r/hXtKCDxSRTa1erWoyc65mUd85cZ5t7T07aLdCcHudpq7f838/XE+zuf+8Xu3PEwTFEsInX UvbKTEf29KeWYvv9sr9PPN6ziPt2a0bN7Q8/uoVSA2eJuPfrHGy/omYg8UpTc2Jd47vjX6W3 VBu9+8K5NveHUaKnx99v7/PYON2DQpiypsYefGMsNfvpo67yX4ZKLMUZiYZazEXFiQBRkQ69 PwQAAA== X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFupgkeLIzCtJLcpLzFFi42LZdlhJTjc4LD3VYM0yM4vVd/vZLFauPspk 8a71HIvFpEPXGC3OXF3IYrH3lrbF/GVP2S2WH//HZHFocjOTA6fH5bOlHptWdbJ5bF5S77H7 ZgObx7mLFR4fn95i8Xi/7yqbx+dNcgEcUVw2Kak5mWWpRfp2CVwZt9btZS7YxlzRueM5UwPj PaYuRk4OCQETiQ9df1m7GLk4hAR2M0psXPaIDSIhLtF87Qc7hC0ssfLfczBbSOA1o8SS/aVd jBwcvAJ2ErsvuIOEWQRUJfpOfWAGsXkFBCVOznzCAmKLCiRJ7LnfCLZLWMBL4vmWRWBxZqDx t57MB4uLCFRJ7P9xlglkJLNAscTNxZYQ52xnlHjz5gUzSJxNQFPiwmSwrZwC5hJfW4shpphJ dG3tYoSw5SW2v53DPIFRaBaSI2YhWTYLScssJC0LGFlWMUqmFhTnpucmGxYY5qWW6xUn5haX 5qXrJefnbmIER5aWxg7Ge/P/6R1iZOJgPMQowcGsJMKr9zE5VYg3JbGyKrUoP76oNCe1+BCj NAeLkjiv4YzZKUIC6YklqdmpqQWpRTBZJg5OqQYm5Xh1mZllqy8+KLJo0z3APdnwXdCUHcIz /L+Ez4hxkelYxKVi5TnxjueBOR2N4n0+f1mmyvi/PPWO5fG3//622wLc0mJ00ytrHRdNSM1W msIz32lH+gYmE/VT2uU5iVdXi79bLRt/ecHOTy3TlMovzFnUZNchKPK39Z8qd8rKib3MiyMe N88qC8tdqMXIGlNnurT1CNPznY+jl70Q+sj3493BvcfPfv7o//nPn5fVF4Qffuz/pFYYcjI/ 8MCetSFPl7z5ern0a20p2wKl8xXH5CS4HkaVpm3pnPLhlF7oJudZDb/2WPeXTfDkCpb++1Az SXrNxKuvQwwDjb4dmLHu/Yow571a1d1P38eUe7kFKLEUZyQaajEXFScCAKSpYlgbAwAA X-CMS-MailID: 20231129151844epcas5p4695d8ac3b14714aa793b527259299144 X-Msg-Generator: CA Content-Type: text/plain; charset="utf-8" CMS-TYPE: 105P DLP-Filter: Pass X-CFilter-Loop: Reflected X-CMS-RootMailID: 20231128222827epcas5p19beb5067fa55290aef73f96dee91c4ec References: <20231128222752.1767344-1-kbusch@meta.com> <20231128222752.1767344-2-kbusch@meta.com> On 11/29/2023 3:57 AM, Keith Busch wrote: > If the user address can't directly be used for reason, like too many > segments or address unalignement, fallback to a copy of the user vec > while keeping the user address pinned for the IO duration so that it > can safely be copied on completion in any process context. The pinning requirement is only for read. But code keeps user-memory pinned for write too. Is there any reason?