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See http://www.infradead.org/rpr.html X-Rspam-User: X-Stat-Signature: 3zz4j4zp7oz38p87g3c6jxnp8z4q1u6g X-Rspamd-Queue-Id: 42E4B2001F X-Rspamd-Server: rspam02 X-HE-Tag: 1729172962-922478 X-HE-Meta: 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 yu9ctIH8 oK9m6mMThBWe4lgZEyXS/yR9YbseEEj+JOCySPbP0e68/hWGCx3GazsuXJed8vyKAzhazzjf5HpJEWkMX3qV3tGdufC2FzyL/F5D76EwkfOK509OfCi5dfWVj0xJrtAOokP7naLGvfr2v+4jkVYs7dKT4Gwp75FAssPpF2I2ywpPUf5pqfOsrYWOckrC3yS2DZPBeTdbCsEK2eFDUxG30zuQteMpqt6G8s6Zi2vh4YEv0lOXLPD/t+V51onbYN4NuJCrv59iM7XSljYhNf3m6TXMbHFYeWM8sFSRi5EOTxm9TpQuFyFy4dfYhrslsNF5SBw/4jFdH645kUyLC+L1tuhL9BI37/VX01hBE7a6mr3ksgG2uumeuUDx4eisXBYak8C1PxdyeGXOkScOa2i3E/usqRiHGe0b86x+t5iajzWwQFjkGgUEWKM0jRXFJ/p3pbdRQ+nxRAuxfiszZDhCICuQB5ujapsAoDG02nzYjVjWj3RqGrucYTEE5lOg6rH4gC12m1jJ9WssROpwlAsS3ZzRvVKG1B6JaiwFgftVLAuhxZAFKnyvXt6xrADHsvM7DVg77 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Thu, Oct 17, 2024 at 10:46:44AM -0300, Jason Gunthorpe wrote: > On Thu, Oct 17, 2024 at 06:12:55AM -0700, Christoph Hellwig wrote: > > On Thu, Oct 17, 2024 at 10:05:39AM -0300, Jason Gunthorpe wrote: > > > Broadly I think whatever flow NVMe uses for P2P will apply to ODP as > > > well. > > > > ODP is a lot simpler than NVMe for P2P actually :( > > What is your thinking there? I'm looking at the latest patches and I > would expect dma_iova_init() to accept a phys so it can call > pci_p2pdma_map_type() once for the whole transaction. It is a slow > operation. You can't do it for the whole transaction. Here is my suggestion for ODP: http://git.infradead.org/?p=users/hch/misc.git;a=shortlog;h=refs/heads/dma-split-wip For NVMe I need to figure out a way to split bios on a per P2P type boundary as we don't have any space to record if something is a bus mapped address.