On 4/13/24 17:59, Matthew Wilcox wrote: > On Sat, Apr 13, 2024 at 01:28:31PM +0200, Bernd Schubert wrote: >> On 2/28/24 19:29, Matthew Wilcox (Oracle) wrote: >>> The one remaining caller of fuse_writepage_locked() already has a folio, >>> so convert this function entirely. Saves a few calls to compound_head() >>> but no attempt is made to support large folios in this patch. >> >> sorry for late review. The part I'm totally confused with (already >> without this patch), why is this handling a single page only and not the >> entire folio? Is it guaranteed that the folio has a single page only? > > Hi Bernd, > > , filesystems have to tell the VFS that they support large folios before > they'll see a large folio. That's a call to mapping_set_large_folios() > today, although there's proposals to make that more granular. > > If there's interest in supporting large folios in FUSE, I'm happy to > help, but my primary motivation is sorting out struct page, not fixing > individual filesystems. Thank you Matthew! Especially for your quick reply on a Saturday! I had totally missed mapping_set_large_folios. I will look into converting fuse to large folios once I get to performance optimizations for our file system. For now I was just going through all recent commits and had already wondered about the single page folio before. Thanks again, Bernd
