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See http://www.infradead.org/rpr.html X-Rspamd-Queue-Id: 6BB3CC0010 X-Stat-Signature: kwqp8hnku1o669ixq1j3migjxgufjcfo X-Rspam-User: X-Rspamd-Server: rspam08 X-HE-Tag: 1674498336-146501 X-HE-Meta: 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 g7yaIi0p xVNhyDAfRJnqKJihs8Joe7O/UVufDalHe9peyowoL/9Q/OGRTIa4ID6xRvYisTaqdAJx+ekfQcLFpkN48IWaEjObD3IB10FPnKyc4zkxHuJrNWLL6cYoZXt64xhUH1jC2S+DYwAdF1LqpQC0xdhqpoOw0CpGGeKA3N+V74ZMN1ltb0f8+DQ2tmqh7K4Vr78WLuz/5p78NWYcb8tKug9JM2SsS3FE7SnOThAl6mUlOXQDzupHBEOqQJPZsxjJjZXeioS7Gt/A/KTe9Kv8Aeq1luzDzZ2zTdn2p7ZJVQGNJ4HdH/SIGK0gAoxIVsb5OZga4IBJr6oyRFyvPZothxo1BKQdzaTT9TWz1zoGXkPVfNYgF4T4FUhE7mN/KwqqpBP4E4ai4R8HPPs8uCQgOFzYBlvmyBKJHvh+Afr7SzHOMOTaFSuqVl6fCveQAWhvEn84U0lBYKl6q1FwFxkw= 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: On Mon, Jan 23, 2023 at 05:30:07PM +0000, David Howells wrote: > Renumber FOLL_PIN and FOLL_GET down to bit 0 and 1 respectively so that > they are coincidentally the same as BIO_PAGE_PINNED and BIO_PAGE_REFFED and > also so that they can be stored in the bottom two bits of a page pointer > (something I'm looking at for zerocopy socket fragments). > > (Note that BIO_PAGE_REFFED should probably be got rid of at some point, > hence why FOLL_PIN is at 0.) > > Also renumber down the other FOLL_* flags to close the gaps. Taking the risk of having a long bikeshed: I much prefer (1U << bitnr) style definition that make it obvious where there are holes, but otherwise: Reviewed-by: Christoph Hellwig