Commit 94dc8bff authored by Matthew Wilcox (Oracle)'s avatar Matthew Wilcox (Oracle) Committed by Andrew Morton
Browse files

mm: return the folio from swapin_readahead 

The unuse_pte_range() caller only wants the folio while do_swap_page()
wants both the page and the folio.  Since do_swap_page() already has logic
for handling both the folio and the page, move the folio-to-page logic
there.  This also lets us allocate larger folios in the SWP_SYNCHRONOUS_IO
path in future.

Link: https://lkml.kernel.org/r/20240807193734.1865400-1-willy@infradead.org


Signed-off-by: default avatarMatthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 09022bc1

mm/memory.c

+2 −4
Original line number Diff line number Diff line
@@ -4091,7 +4091,6 @@ vm_fault_t do_swap_page(struct vm_fault *vmf) 
			/* skip swapcache */

			folio = vma_alloc_folio(GFP_HIGHUSER_MOVABLE, 0,

						vma, vmf->address, false);

			page = &folio->page;

			if (folio) {

				__folio_set_locked(folio);

				__folio_set_swapbacked(folio);
@@ -4116,10 +4115,8 @@ vm_fault_t do_swap_page(struct vm_fault *vmf) 
				folio->private = NULL;

			}

		} else {

			page = swapin_readahead(entry, GFP_HIGHUSER_MOVABLE,

			folio = swapin_readahead(entry, GFP_HIGHUSER_MOVABLE,

						vmf);

			if (page)

				folio = page_folio(page);

			swapcache = folio;

		}
@@ -4140,6 +4137,7 @@ vm_fault_t do_swap_page(struct vm_fault *vmf) 
		ret = VM_FAULT_MAJOR;

		count_vm_event(PGMAJFAULT);

		count_memcg_event_mm(vma->vm_mm, PGMAJFAULT);

		page = folio_file_page(folio, swp_offset(entry));

	} else if (PageHWPoison(page)) {

		/*

		 * hwpoisoned dirty swapcache pages are kept for killing

mm/swap.h

+3 −3
Original line number Diff line number Diff line
@@ -73,7 +73,7 @@ struct folio *__read_swap_cache_async(swp_entry_t entry, gfp_t gfp_flags, 
		bool skip_if_exists);

struct folio *swap_cluster_readahead(swp_entry_t entry, gfp_t flag,

		struct mempolicy *mpol, pgoff_t ilx);

struct page *swapin_readahead(swp_entry_t entry, gfp_t flag,

struct folio *swapin_readahead(swp_entry_t entry, gfp_t flag,

		struct vm_fault *vmf);



static inline unsigned int folio_swap_flags(struct folio *folio)
@@ -109,7 +109,7 @@ static inline struct folio *swap_cluster_readahead(swp_entry_t entry, 
	return NULL;

}



static inline struct page *swapin_readahead(swp_entry_t swp, gfp_t gfp_mask,

static inline struct folio *swapin_readahead(swp_entry_t swp, gfp_t gfp_mask,

			struct vm_fault *vmf)

{

	return NULL;

mm/swap_state.c

+3 −5
Original line number Diff line number Diff line
@@ -863,13 +863,13 @@ static struct folio *swap_vma_readahead(swp_entry_t targ_entry, gfp_t gfp_mask, 
 * @gfp_mask: memory allocation flags

 * @vmf: fault information

 *

 * Returns the struct page for entry and addr, after queueing swapin.

 * Returns the struct folio for entry and addr, after queueing swapin.

 *

 * It's a main entry function for swap readahead. By the configuration,

 * it will read ahead blocks by cluster-based(ie, physical disk based)

 * or vma-based(ie, virtual address based on faulty address) readahead.

 */

struct page *swapin_readahead(swp_entry_t entry, gfp_t gfp_mask,

struct folio *swapin_readahead(swp_entry_t entry, gfp_t gfp_mask,

				struct vm_fault *vmf)

{

	struct mempolicy *mpol;
@@ -882,9 +882,7 @@ struct page *swapin_readahead(swp_entry_t entry, gfp_t gfp_mask, 
		swap_cluster_readahead(entry, gfp_mask, mpol, ilx);

	mpol_cond_put(mpol);



	if (!folio)

		return NULL;

	return folio_file_page(folio, swp_offset(entry));

	return folio;

}



#ifdef CONFIG_SYSFS

mm/swapfile.c

+1 −4
Original line number Diff line number Diff line
@@ -1980,7 +1980,6 @@ static int unuse_pte_range(struct vm_area_struct *vma, pmd_t *pmd, 


		folio = swap_cache_get_folio(entry, vma, addr);

		if (!folio) {

			struct page *page;

			struct vm_fault vmf = {

				.vma = vma,

				.address = addr,
@@ -1988,10 +1987,8 @@ static int unuse_pte_range(struct vm_area_struct *vma, pmd_t *pmd, 
				.pmd = pmd,

			};



			page = swapin_readahead(entry, GFP_HIGHUSER_MOVABLE,

			folio = swapin_readahead(entry, GFP_HIGHUSER_MOVABLE,

						&vmf);

			if (page)

				folio = page_folio(page);

		}

		if (!folio) {

			swp_count = READ_ONCE(si->swap_map[offset]);