All callers now expect head (and base) pages, and can handle multiple head pages in a single batch, so make find_get_entries() behave that way. Also take the opportunity to make it use the pagevec infrastructure instead of open-coding how pvecs behave. This has the side-effect of being able to append to a pagevec with existing contents, although we don't make use of that functionality anywhere yet.
Signed-off-by: Matthew Wilcox (Oracle) <[email protected]> Reviewed-by: Jan Kara <[email protected]> Reviewed-by: William Kucharski <[email protected]> --- include/linux/pagemap.h | 2 -- mm/filemap.c | 36 ++++++++---------------------------- mm/internal.h | 2 ++ 3 files changed, 10 insertions(+), 30 deletions(-) diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index 46d4b1704770..65ef8db8eaab 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -448,8 +448,6 @@ static inline struct page *find_subpage(struct page *head, pgoff_t index) return head + (index & (thp_nr_pages(head) - 1)); } -unsigned find_get_entries(struct address_space *mapping, pgoff_t start, - pgoff_t end, struct pagevec *pvec, pgoff_t *indices); unsigned find_get_pages_range(struct address_space *mapping, pgoff_t *start, pgoff_t end, unsigned int nr_pages, struct page **pages); diff --git a/mm/filemap.c b/mm/filemap.c index 479cbbadd93b..f8c294905e8d 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -1878,49 +1878,29 @@ static inline struct page *find_get_entry(struct xa_state *xas, pgoff_t max, * the mapping. The entries are placed in @pvec. find_get_entries() * takes a reference on any actual pages it returns. * - * The search returns a group of mapping-contiguous page cache entries - * with ascending indexes. There may be holes in the indices due to - * not-present pages. + * The entries have ascending indexes. The indices may not be consecutive + * due to not-present entries or THPs. * * Any shadow entries of evicted pages, or swap entries from * shmem/tmpfs, are included in the returned array. * - * If it finds a Transparent Huge Page, head or tail, find_get_entries() - * stops at that page: the caller is likely to have a better way to handle - * the compound page as a whole, and then skip its extent, than repeatedly - * calling find_get_entries() to return all its tails. - * - * Return: the number of pages and shadow entries which were found. + * Return: The number of entries which were found. */ unsigned find_get_entries(struct address_space *mapping, pgoff_t start, pgoff_t end, struct pagevec *pvec, pgoff_t *indices) { XA_STATE(xas, &mapping->i_pages, start); struct page *page; - unsigned int ret = 0; - unsigned nr_entries = PAGEVEC_SIZE; rcu_read_lock(); while ((page = find_get_entry(&xas, end, XA_PRESENT))) { - /* - * Terminate early on finding a THP, to allow the caller to - * handle it all at once; but continue if this is hugetlbfs. - */ - if (!xa_is_value(page) && PageTransHuge(page) && - !PageHuge(page)) { - page = find_subpage(page, xas.xa_index); - nr_entries = ret + 1; - } - - indices[ret] = xas.xa_index; - pvec->pages[ret] = page; - if (++ret == nr_entries) + indices[pvec->nr] = xas.xa_index; + if (!pagevec_add(pvec, page)) break; } rcu_read_unlock(); - pvec->nr = ret; - return ret; + return pagevec_count(pvec); } /** @@ -1939,8 +1919,8 @@ unsigned find_get_entries(struct address_space *mapping, pgoff_t start, * not returned. * * The entries have ascending indexes. The indices may not be consecutive - * due to not-present entries, THP pages, pages which could not be locked - * or pages under writeback. + * due to not-present entries, THPs, pages which could not be locked or + * pages under writeback. * * Return: The number of entries which were found. */ diff --git a/mm/internal.h b/mm/internal.h index cb7487efa856..1f137a5d66bb 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -60,6 +60,8 @@ static inline void force_page_cache_readahead(struct address_space *mapping, force_page_cache_ra(&ractl, &file->f_ra, nr_to_read); } +unsigned find_get_entries(struct address_space *mapping, pgoff_t start, + pgoff_t end, struct pagevec *pvec, pgoff_t *indices); unsigned find_lock_entries(struct address_space *mapping, pgoff_t start, pgoff_t end, struct pagevec *pvec, pgoff_t *indices); -- 2.28.0
