diff options
| -rw-r--r-- | mm/filemap.c | 59 | ||||
| -rw-r--r-- | mm/internal.h | 3 | ||||
| -rw-r--r-- | mm/shmem.c | 22 | ||||
| -rw-r--r-- | mm/truncate.c | 91 |
4 files changed, 78 insertions, 97 deletions
diff --git a/mm/filemap.c b/mm/filemap.c index 6a34f94adf3b..61fdcdc75275 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -1921,6 +1921,65 @@ unsigned find_get_entries(struct address_space *mapping, } /** + * find_lock_entries - Find a batch of pagecache entries. + * @mapping: The address_space to search. + * @start: The starting page cache index. + * @end: The final page index (inclusive). + * @pvec: Where the resulting entries are placed. + * @indices: The cache indices of the entries in @pvec. + * + * find_lock_entries() will return a batch of entries from @mapping. + * Swap, shadow and DAX entries are included. Pages are returned + * locked and with an incremented refcount. Pages which are locked by + * somebody else or under writeback are skipped. Only the head page of + * a THP is returned. Pages which are partially outside the range are + * 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. + * + * Return: The number of entries which were found. + */ +unsigned find_lock_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; + + rcu_read_lock(); + while ((page = find_get_entry(&xas, end, XA_PRESENT))) { + if (!xa_is_value(page)) { + if (page->index < start) + goto put; + VM_BUG_ON_PAGE(page->index != xas.xa_index, page); + if (page->index + thp_nr_pages(page) - 1 > end) + goto put; + if (!trylock_page(page)) + goto put; + if (page->mapping != mapping || PageWriteback(page)) + goto unlock; + VM_BUG_ON_PAGE(!thp_contains(page, xas.xa_index), + page); + } + indices[pvec->nr] = xas.xa_index; + if (!pagevec_add(pvec, page)) + break; + goto next; +unlock: + unlock_page(page); +put: + put_page(page); +next: + if (!xa_is_value(page) && PageTransHuge(page)) + xas_set(&xas, page->index + thp_nr_pages(page)); + } + rcu_read_unlock(); + + return pagevec_count(pvec); +} + +/** * find_get_pages_range - gang pagecache lookup * @mapping: The address_space to search * @start: The starting page index diff --git a/mm/internal.h b/mm/internal.h index eed74f1e6147..9902648f2206 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -60,6 +60,9 @@ static inline void force_page_cache_readahead(struct address_space *mapping, force_page_cache_ra(&ractl, &file->f_ra, nr_to_read); } +unsigned find_lock_entries(struct address_space *mapping, pgoff_t start, + pgoff_t end, struct pagevec *pvec, pgoff_t *indices); + /** * page_evictable - test whether a page is evictable * @page: the page to test diff --git a/mm/shmem.c b/mm/shmem.c index deb22e128435..86b1f5bc502c 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -907,12 +907,8 @@ static void shmem_undo_range(struct inode *inode, loff_t lstart, loff_t lend, pagevec_init(&pvec); index = start; - while (index < end) { - pvec.nr = find_get_entries(mapping, index, - min(end - index, (pgoff_t)PAGEVEC_SIZE), - pvec.pages, indices); - if (!pvec.nr) - break; + while (index < end && find_lock_entries(mapping, index, end - 1, + &pvec, indices)) { for (i = 0; i < pagevec_count(&pvec); i++) { struct page *page = pvec.pages[i]; @@ -927,18 +923,10 @@ static void shmem_undo_range(struct inode *inode, loff_t lstart, loff_t lend, index, page); continue; } + index += thp_nr_pages(page) - 1; - VM_BUG_ON_PAGE(page_to_pgoff(page) != index, page); - - if (!trylock_page(page)) - continue; - - if ((!unfalloc || !PageUptodate(page)) && - page_mapping(page) == mapping) { - VM_BUG_ON_PAGE(PageWriteback(page), page); - if (shmem_punch_compound(page, start, end)) - truncate_inode_page(mapping, page); - } + if (!unfalloc || !PageUptodate(page)) + truncate_inode_page(mapping, page); unlock_page(page); } pagevec_remove_exceptionals(&pvec); diff --git a/mm/truncate.c b/mm/truncate.c index 8aa4907e06e0..de7f4f47f780 100644 --- a/mm/truncate.c +++ b/mm/truncate.c @@ -326,51 +326,19 @@ void truncate_inode_pages_range(struct address_space *mapping, pagevec_init(&pvec); index = start; - while (index < end && pagevec_lookup_entries(&pvec, mapping, index, - min(end - index, (pgoff_t)PAGEVEC_SIZE), - indices)) { - /* - * Pagevec array has exceptional entries and we may also fail - * to lock some pages. So we store pages that can be deleted - * in a new pagevec. - */ - struct pagevec locked_pvec; - - pagevec_init(&locked_pvec); - for (i = 0; i < pagevec_count(&pvec); i++) { - struct page *page = pvec.pages[i]; - - /* We rely upon deletion not changing page->index */ - index = indices[i]; - if (index >= end) - break; - - if (xa_is_value(page)) - continue; - - if (!trylock_page(page)) - continue; - WARN_ON(page_to_index(page) != index); - if (PageWriteback(page)) { - unlock_page(page); - continue; - } - if (page->mapping != mapping) { - unlock_page(page); - continue; - } - pagevec_add(&locked_pvec, page); - } - for (i = 0; i < pagevec_count(&locked_pvec); i++) - truncate_cleanup_page(mapping, locked_pvec.pages[i]); - delete_from_page_cache_batch(mapping, &locked_pvec); - for (i = 0; i < pagevec_count(&locked_pvec); i++) - unlock_page(locked_pvec.pages[i]); + while (index < end && find_lock_entries(mapping, index, end - 1, + &pvec, indices)) { + index = indices[pagevec_count(&pvec) - 1] + 1; truncate_exceptional_pvec_entries(mapping, &pvec, indices, end); + for (i = 0; i < pagevec_count(&pvec); i++) + truncate_cleanup_page(mapping, pvec.pages[i]); + delete_from_page_cache_batch(mapping, &pvec); + for (i = 0; i < pagevec_count(&pvec); i++) + unlock_page(pvec.pages[i]); pagevec_release(&pvec); cond_resched(); - index++; } + if (partial_start) { struct page *page = find_lock_page(mapping, start - 1); if (page) { @@ -539,9 +507,7 @@ static unsigned long __invalidate_mapping_pages(struct address_space *mapping, int i; pagevec_init(&pvec); - while (index <= end && pagevec_lookup_entries(&pvec, mapping, index, - min(end - index, (pgoff_t)PAGEVEC_SIZE - 1) + 1, - indices)) { + while (find_lock_entries(mapping, index, end, &pvec, indices)) { for (i = 0; i < pagevec_count(&pvec); i++) { struct page *page = pvec.pages[i]; @@ -555,39 +521,7 @@ static unsigned long __invalidate_mapping_pages(struct address_space *mapping, page); continue; } - - if (!trylock_page(page)) - continue; - - WARN_ON(page_to_index(page) != index); - - /* Middle of THP: skip */ - if (PageTransTail(page)) { - unlock_page(page); - continue; - } else if (PageTransHuge(page)) { - index += HPAGE_PMD_NR - 1; - i += HPAGE_PMD_NR - 1; - /* - * 'end' is in the middle of THP. Don't - * invalidate the page as the part outside of - * 'end' could be still useful. - */ - if (index > end) { - unlock_page(page); - continue; - } - - /* Take a pin outside pagevec */ - get_page(page); - - /* - * Drop extra pins before trying to invalidate - * the huge page. - */ - pagevec_remove_exceptionals(&pvec); - pagevec_release(&pvec); - } + index += thp_nr_pages(page) - 1; ret = invalidate_inode_page(page); unlock_page(page); @@ -601,9 +535,6 @@ static unsigned long __invalidate_mapping_pages(struct address_space *mapping, if (nr_pagevec) (*nr_pagevec)++; } - - if (PageTransHuge(page)) - put_page(page); count += ret; } pagevec_remove_exceptionals(&pvec); |