diff --git a/mm/filemap.c b/mm/filemap.c index 38546dca58fe..3b76d79fd0cf 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -829,13 +829,12 @@ EXPORT_SYMBOL_GPL(replace_page_cache_page); static int __add_to_page_cache_locked(struct page *page, struct address_space *mapping, - pgoff_t offset, gfp_t gfp_mask, + pgoff_t offset, gfp_t gfp, void **shadowp) { XA_STATE(xas, &mapping->i_pages, offset); int huge = PageHuge(page); int error; - void *old; VM_BUG_ON_PAGE(!PageLocked(page), page); VM_BUG_ON_PAGE(PageSwapBacked(page), page); @@ -846,25 +845,46 @@ static int __add_to_page_cache_locked(struct page *page, page->index = offset; if (!huge) { - error = mem_cgroup_charge(page, current->mm, gfp_mask); + error = mem_cgroup_charge(page, current->mm, gfp); if (error) goto error; } + gfp &= GFP_RECLAIM_MASK; + do { + unsigned int order = xa_get_order(xas.xa, xas.xa_index); + void *entry, *old = NULL; + + if (order > thp_order(page)) + xas_split_alloc(&xas, xa_load(xas.xa, xas.xa_index), + order, gfp); xas_lock_irq(&xas); - old = xas_load(&xas); - if (old && !xa_is_value(old)) - xas_set_err(&xas, -EEXIST); + xas_for_each_conflict(&xas, entry) { + old = entry; + if (!xa_is_value(entry)) { + xas_set_err(&xas, -EEXIST); + goto unlock; + } + } + + if (old) { + if (shadowp) + *shadowp = old; + /* entry may have been split before we acquired lock */ + order = xa_get_order(xas.xa, xas.xa_index); + if (order > thp_order(page)) { + xas_split(&xas, old, order); + xas_reset(&xas); + } + } + xas_store(&xas, page); if (xas_error(&xas)) goto unlock; - if (xa_is_value(old)) { + if (old) mapping->nrexceptional--; - if (shadowp) - *shadowp = old; - } mapping->nrpages++; /* hugetlb pages do not participate in page cache accounting */ @@ -872,7 +892,7 @@ static int __add_to_page_cache_locked(struct page *page, __inc_lruvec_page_state(page, NR_FILE_PAGES); unlock: xas_unlock_irq(&xas); - } while (xas_nomem(&xas, gfp_mask & GFP_RECLAIM_MASK)); + } while (xas_nomem(&xas, gfp)); if (xas_error(&xas)) { error = xas_error(&xas);