• MatthewWilcox
• Projects

I have "a few" projects I'm working on / intending to work on in the near future.

Folios is the big one. This has sub-projects:

• MM:
  • Convert vmscan.c to folios (partly done for 5.18)
    • isolate_lru_pages()
    • alloc_demote_page()
    • reclaim_clean_pages_from_list()
    • move_pages_to_lru()
    • shrink_active_list()
    • reclaim_pages()
  • Convert filemap.c to folios
    • filemap_range_has_page()

    • filemap_fdatawait_range()

    • filemap_range_has_writeback()
    • replace_page_cache_page()
    • page_endio()
    • find_get_pages_contig() (or can we remove it?)
    • find_get_pages_range_tag()
    • filemap_map_pmd()
    • filemap_map_pages()
    • generic_perform_write()
  • Get rid of readahead_page()
  • Move split_huge_page() to non-THP code
  • Get rid of all thp_size(), thp_order() and thp_nr_pages() calls (probably?)
• FS:
  • Adapt NFS to use large folios
  • Adapt btrfs to use large folios
  • Adapt CIFS to use large folios
  • Convert the a_ops to take folios instead of pages (most aops done for 5.19)

Tangential to folios:

• Phyr
• net pool as its own type
• pt pages as its own type
• zspage as its own type
• Can we make mapcount more sensible or disappear entirely?

• Implement iomap ->writepages properly

Unrelated to folios:

• Maple Tree (Liam is doing most of the work)
• Shrink struct mutex (Vishal has taken this on)
• Remove PG_private
• Remove PG_error

• Synchronous ->readpage

• Broadcast readpage errors to all waiters

• Implement ->readahead for squashfs (Hsin-Yi)

• MatthewWilcox/ImprovedReadaheadAlgorithm

• Slab Sevenths (Bill is attacking this one)
• NUMA-aware zero page (Bill is working on this one too)
• NUMA text pages in the page cache (Linus seems sceptical)
• Usercopy for order-0 pages

  • If we check ->mapping, is that a sure sign of individual allocation?

• Big Buckets (or integrate with Maple Tree)
• Readahead for compressed filesystems in general
• Fix XArray memory leak when memory allocation fails
• Removing b_end_io (Jitendra)
• Enable -Wshadow (needs header file cleanups)
• Share memory when caching reflinked files
• Make page cache better at writethrough for O_SYNC (and related)

Completed projects

• Folios:
• MM:
  • Get large folio support in (5.18)
  • Convert GUP to folios (5.18)
  • Convert page_vma_mapped to PFNs (5.18)
  • Convert rmap to folios (5.18)
• FS:
  • Convert XFS to large folios (5.18)

• Remove aops->readpages (5.18)

• Use an iov_iter in proc/vmcore (5.19)
• Usercopy improvements (5.19)
• Make the last argument to read_mapping_page() / read_mapping_folio() a struct file ptr (5.19)
• Slab (Vlastimil took this over. merged 5.17)