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See http://www.infradead.org/rpr.html X-Rspam-User: X-Rspamd-Server: rspam08 X-Rspamd-Queue-Id: 5E47840003 X-Stat-Signature: ppmwibkq1hpphuuutegg5xrtniyczuso X-HE-Tag: 1740413840-469884 X-HE-Meta: U2FsdGVkX1/ArjMeX8+ii7IvHx5anM04lnHa/vj9btvL5sRIZpsOFIkxtdzlMIhyPdAyBGIQIe6K0uydX9Mvytmt7o2d65Y8I1kZ0J2Tl9N+WOBDdYGzNmaoggytDsrTmsCU+Qxv2EGL5OHLH5PmKBkNXbgGYatxGoIgABmWD6qUAzY3hZV2XMmpahucdrK3tDvV3IVkPDQK/SruixYOWy/vDVbPJkdUR4JNxWg0SdQdqsxqCEGMZ+5m3YCHYZI9ApgsczD3SBGodvU8jEpmlG1TGEJa4u6tv2kynss1aB9LXq+lxc52modVgFtFpmFfDa94Ll5/EFVHsi4w5M8fymKjmUQJW/4zQh69NiJA8TOyWtFOOwPJATfqJrzOfW9XGi8YQFAmrCp/7hrxyolfXSMTbiXqEntb8uTmoQdovbZqAQKizFNq3uZ5IivZSQ4M7c/wOFEunlpEg/9Hjpr8D3C2CH2BHetvuIJI4I5vcL+OwuCccokQ4c2+fHLvtqw4Xp6QS/zFIbVOEfIRcx1D1gWzckwfTtn4QOKmB7RN7UPEcF72awVKpXM8jKtvWmjD80muMfS5Fxi+PGI53yPKn/tbtTN0y+tIFD0dCKdceLZIM4ZSlDYMuJXfs4Ejv+nNRl0eu72VRgz2AgoBuK4vFezwM6+gIauQ9goiqNfSV3f5cPJ7CcrnCS6vemi+5yYpF+RCWZLdFogQAbDQAgr25pbv4tBTbYnDlo9s/mElfCJ2I5oNq1A18z5cn3mcuPo4yH5a83+o/Gqoo7Br5lZBUyVJWPl1HjF1XU1GWGKgN/ibjiANMEYR7JzPpm2JBXH76SUfZIeUixXG5kUcfJ3hSkThDtfKoety/buXPB56ttxwBVbknOppdTzZRTln5ujfVdMINTt0d4ZT/g3wI8ZgDZ2e/I8podwS4dnMNRwVa6FYG9cMyxr1i73HClUilbO9vLGag3M7G8hw3WqC2F+ FfUEXhw7 jNcLtl5x9jtwK/3Sgulaz2j3rCER0COU84uhm6Ec7TvCHHpUjztbiON3qOuLBIIL0a1J7ytEZY1MT53uueWgEI3Urji+MAA8TsA49EuLt467qSf2Cxtf+jrCPKUmJcfH4buZj6OstF/PZLk+BO5zCIwYAd4TQlGh2B5OtVCNR7G8yYJNM9OP9hIqTMjapFr0tTI/YQx3KOcV1QxTPy7a3OYywfGu4Ivz2IrZasfYs62r2POfjEVaWcWErbXUyXcmteQQpX4BbpODXNJfuw/fTUHEurZ+lJdhF4OIFGfNZANKLLIT+mp6aQ5tu1kjJXNAT6P7C/UbhJJzd7RETlE/cqZzoVAMitFabQEmvFF7E6xmU8FoncvF87rGc0lxb+5Qh7p7mf1WU76oeoEMVV2ZgRx0BYtnMkiA32Syu9jAvPtYKY0VWfjWvfwMINtrTw88fwwNDWcx0XQ1aiz8BHwsinRf52Cb/BDPxlmzC 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 Sun, Feb 23, 2025 at 01:47:52AM +0000, Matthew Wilcox wrote: > - Choose a data structure in the VFS to store this range information > (a tree of some kind) > - Design a protocol such that the VFS can query this information about > a range of a particular file, and the filesystem can invalidate the > VFS's knowledge That information is always going to be incoherent in some way. Reads are already done without i_rwsem for most file systems and there is further work on reducing locking. So anything needs to come from inside the file system itself. That probably means you can't reduce the folio allocation overhead, but at least you don't have to persistently use the memory.