kernel/linux.git/include/linux/rmap.h, branch v5.18.16

mm/rmap: Constify the rmap_walk_control argument

2022-03-21T17:01:35+00:00

The rmap walking functions do not modify the rmap_walk_control, and page_idle_clear_pte_refs() takes advantage of that to move construction of the rmap_walk_control to compile time. This lets us remove an unclean cast. Signed-off-by: Matthew Wilcox (Oracle)

mm/rmap: Convert rmap_walk() to take a folio

2022-03-21T17:01:35+00:00

This ripples all the way through to every calling and called function from rmap. Signed-off-by: Matthew Wilcox (Oracle)

mm/rmap: Turn page_lock_anon_vma_read() into folio_lock_anon_vma_read()

2022-03-21T17:01:35+00:00

Add back page_lock_anon_vma_read() as a wrapper. This saves a few calls to compound_head(). If any callers were passing a tail page before, this would have failed to lock the anon VMA as page->mapping is not valid for tail pages. Signed-off-by: Matthew Wilcox (Oracle)

mm/migrate: Convert remove_migration_ptes() to folios

2022-03-21T17:01:35+00:00

Convert the implementation and all callers. Signed-off-by: Matthew Wilcox (Oracle)

mm/rmap: Convert try_to_migrate() to folios

2022-03-21T17:01:32+00:00

Convert the callers to pass a folio and the try_to_migrate_one() worker to use a folio throughout. Fixes an assumption that a folio must be <= PMD size. Signed-off-by: Matthew Wilcox (Oracle)

mm/rmap: Convert try_to_unmap() to take a folio

2022-03-21T16:59:03+00:00

Change all three callers and the worker function try_to_unmap_one(). Signed-off-by: Matthew Wilcox (Oracle)

mm/rmap: Turn page_referenced() into folio_referenced()

2022-03-21T16:59:03+00:00

Both its callers pass a page which was previously on an LRU list, so were passing a folio by definition. Use the type system to enforce that and remove a few calls to compound_head(). Signed-off-by: Matthew Wilcox (Oracle) Reviewed-by: Christoph Hellwig

mm: Convert page_vma_mapped_walk to work on PFNs

2022-03-21T16:59:02+00:00

page_mapped_in_vma() really just wants to walk one page, but as the code stands, if passed the head page of a compound page, it will walk every page in the compound page. Extract pfn/nr_pages/pgoff from the struct page early, so they can be overridden by page_mapped_in_vma(). Signed-off-by: Matthew Wilcox (Oracle)

mm: Add DEFINE_PAGE_VMA_WALK and DEFINE_FOLIO_VMA_WALK

2022-03-21T16:59:02+00:00

Instead of declaring a struct page_vma_mapped_walk directly, use these helpers to allow us to transition to a PFN approach in the following patches. Signed-off-by: Matthew Wilcox (Oracle)

mm/munlock: rmap call mlock_vma_page() munlock_vma_page()

2022-02-17T16:56:48+00:00

Add vma argument to mlock_vma_page() and munlock_vma_page(), make them inline functions which check (vma->vm_flags & VM_LOCKED) before calling mlock_page() and munlock_page() in mm/mlock.c. Add bool compound to mlock_vma_page() and munlock_vma_page(): this is because we have understandable difficulty in accounting pte maps of THPs, and if passed a PageHead page, mlock_page() and munlock_page() cannot tell whether it's a pmd map to be counted or a pte map to be ignored. Add vma arg to page_add_file_rmap() and page_remove_rmap(), like the others, and use that to call mlock_vma_page() at the end of the page adds, and munlock_vma_page() at the end of page_remove_rmap() (end or beginning? unimportant, but end was easier for assertions in testing). No page lock is required (although almost all adds happen to hold it): delete the "Serialize with page migration" BUG_ON(!PageLocked(page))s. Certainly page lock did serialize with page migration, but I'm having difficulty explaining why that was ever important. Mlock accounting on THPs has been hard to define, differed between anon and file, involved PageDoubleMap in some places and not others, required clear_page_mlock() at some points. Keep it simple now: just count the pmds and ignore the ptes, there is no reason for ptes to undo pmd mlocks. page_add_new_anon_rmap() callers unchanged: they have long been calling lru_cache_add_inactive_or_unevictable(), which does its own VM_LOCKED handling (it also checks for not VM_SPECIAL: I think that's overcautious, and inconsistent with other checks, that mmap_region() already prevents VM_LOCKED on VM_SPECIAL; but haven't quite convinced myself to change it). Signed-off-by: Hugh Dickins Acked-by: Vlastimil Babka Signed-off-by: Matthew Wilcox (Oracle)