The patch titled
Subject: mm: return the folio from __read_swap_cache_async()
has been added to the -mm mm-unstable branch. Its filename is
mm-return-the-folio-from-__read_swap_cache_async.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-return-the-folio-from-__read_swap_cache_async.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx>
Subject: mm: return the folio from __read_swap_cache_async()
Date: Wed, 13 Dec 2023 21:58:30 +0000
Patch series "More swap folio conversions".
These all seem like fairly straightforward conversions to me. A lot of
compound_head() calls get removed. And page_swap_info(), which is nice.
This patch (of 13):
Move the folio->page conversion into the callers that actually want that.
Most of the callers are happier with the folio anyway. If the
page_allocated boolean is set, the folio allocated is of order-0, so it is
safe to pass the page directly to swap_readpage().
Link: https://lkml.kernel.org/r/20231213215842.671461-1-willy@xxxxxxxxxxxxx
Link: https://lkml.kernel.org/r/20231213215842.671461-2-willy@xxxxxxxxxxxxx
Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/zswap.h | 4 +-
mm/swap.h | 7 +--
mm/swap_state.c | 75 ++++++++++++++++++----------------------
mm/zswap.c | 46 ++++++++++++------------
4 files changed, 63 insertions(+), 69 deletions(-)
--- a/include/linux/zswap.h~mm-return-the-folio-from-__read_swap_cache_async
+++ a/include/linux/zswap.h
@@ -34,7 +34,7 @@ void zswap_swapon(int type);
void zswap_swapoff(int type);
void zswap_memcg_offline_cleanup(struct mem_cgroup *memcg);
void zswap_lruvec_state_init(struct lruvec *lruvec);
-void zswap_page_swapin(struct page *page);
+void zswap_folio_swapin(struct folio *folio);
bool is_zswap_enabled(void);
#else
@@ -55,7 +55,7 @@ static inline void zswap_swapon(int type
static inline void zswap_swapoff(int type) {}
static inline void zswap_memcg_offline_cleanup(struct mem_cgroup *memcg) {}
static inline void zswap_lruvec_state_init(struct lruvec *lruvec) {}
-static inline void zswap_page_swapin(struct page *page) {}
+static inline void zswap_folio_swapin(struct folio *folio) {}
static inline bool is_zswap_enabled(void)
{
--- a/mm/swap.h~mm-return-the-folio-from-__read_swap_cache_async
+++ a/mm/swap.h
@@ -49,10 +49,9 @@ struct page *read_swap_cache_async(swp_e
struct vm_area_struct *vma,
unsigned long addr,
struct swap_iocb **plug);
-struct page *__read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask,
- struct mempolicy *mpol, pgoff_t ilx,
- bool *new_page_allocated,
- bool skip_if_exists);
+struct folio *__read_swap_cache_async(swp_entry_t entry, gfp_t gfp_flags,
+ struct mempolicy *mpol, pgoff_t ilx, bool *new_page_allocated,
+ bool skip_if_exists);
struct page *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,
--- a/mm/swap_state.c~mm-return-the-folio-from-__read_swap_cache_async
+++ a/mm/swap_state.c
@@ -410,14 +410,12 @@ struct folio *filemap_get_incore_folio(s
return folio;
}
-struct page *__read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask,
- struct mempolicy *mpol, pgoff_t ilx,
- bool *new_page_allocated,
- bool skip_if_exists)
+struct folio *__read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask,
+ struct mempolicy *mpol, pgoff_t ilx, bool *new_page_allocated,
+ bool skip_if_exists)
{
struct swap_info_struct *si;
struct folio *folio;
- struct page *page;
void *shadow = NULL;
*new_page_allocated = false;
@@ -434,10 +432,8 @@ struct page *__read_swap_cache_async(swp
*/
folio = filemap_get_folio(swap_address_space(entry),
swp_offset(entry));
- if (!IS_ERR(folio)) {
- page = folio_file_page(folio, swp_offset(entry));
- goto got_page;
- }
+ if (!IS_ERR(folio))
+ goto got_folio;
/*
* Just skip read ahead for unused swap slot.
@@ -451,7 +447,7 @@ struct page *__read_swap_cache_async(swp
goto fail_put_swap;
/*
- * Get a new page to read into from swap. Allocate it now,
+ * Get a new folio to read into from swap. Allocate it now,
* before marking swap_map SWAP_HAS_CACHE, when -EEXIST will
* cause any racers to loop around until we add it to cache.
*/
@@ -487,13 +483,13 @@ struct page *__read_swap_cache_async(swp
* stumble across a swap_map entry whose SWAP_HAS_CACHE
* has not yet been cleared. Or race against another
* __read_swap_cache_async(), which has set SWAP_HAS_CACHE
- * in swap_map, but not yet added its page to swap cache.
+ * in swap_map, but not yet added its folio to swap cache.
*/
schedule_timeout_uninterruptible(1);
}
/*
- * The swap entry is ours to swap in. Prepare the new page.
+ * The swap entry is ours to swap in. Prepare the new folio.
*/
__folio_set_locked(folio);
@@ -514,10 +510,9 @@ struct page *__read_swap_cache_async(swp
/* Caller will initiate read into locked folio */
folio_add_lru(folio);
*new_page_allocated = true;
- page = &folio->page;
-got_page:
+got_folio:
put_swap_device(si);
- return page;
+ return folio;
fail_unlock:
put_swap_folio(folio, entry);
@@ -545,16 +540,16 @@ struct page *read_swap_cache_async(swp_e
bool page_allocated;
struct mempolicy *mpol;
pgoff_t ilx;
- struct page *page;
+ struct folio *folio;
mpol = get_vma_policy(vma, addr, 0, &ilx);
- page = __read_swap_cache_async(entry, gfp_mask, mpol, ilx,
+ folio = __read_swap_cache_async(entry, gfp_mask, mpol, ilx,
&page_allocated, false);
mpol_cond_put(mpol);
if (page_allocated)
- swap_readpage(page, false, plug);
- return page;
+ swap_readpage(&folio->page, false, plug);
+ return folio_file_page(folio, swp_offset(entry));
}
static unsigned int __swapin_nr_pages(unsigned long prev_offset,
@@ -639,7 +634,7 @@ static unsigned long swapin_nr_pages(uns
struct page *swap_cluster_readahead(swp_entry_t entry, gfp_t gfp_mask,
struct mempolicy *mpol, pgoff_t ilx)
{
- struct page *page;
+ struct folio *folio;
unsigned long entry_offset = swp_offset(entry);
unsigned long offset = entry_offset;
unsigned long start_offset, end_offset;
@@ -664,31 +659,31 @@ struct page *swap_cluster_readahead(swp_
blk_start_plug(&plug);
for (offset = start_offset; offset <= end_offset ; offset++) {
/* Ok, do the async read-ahead now */
- page = __read_swap_cache_async(
+ folio = __read_swap_cache_async(
swp_entry(swp_type(entry), offset),
gfp_mask, mpol, ilx, &page_allocated, false);
- if (!page)
+ if (!folio)
continue;
if (page_allocated) {
- swap_readpage(page, false, &splug);
+ swap_readpage(&folio->page, false, &splug);
if (offset != entry_offset) {
- SetPageReadahead(page);
+ folio_set_readahead(folio);
count_vm_event(SWAP_RA);
}
}
- put_page(page);
+ folio_put(folio);
}
blk_finish_plug(&plug);
swap_read_unplug(splug);
lru_add_drain(); /* Push any new pages onto the LRU now */
skip:
/* The page was likely read above, so no need for plugging here */
- page = __read_swap_cache_async(entry, gfp_mask, mpol, ilx,
+ folio = __read_swap_cache_async(entry, gfp_mask, mpol, ilx,
&page_allocated, false);
if (unlikely(page_allocated))
- swap_readpage(page, false, NULL);
- zswap_page_swapin(page);
- return page;
+ swap_readpage(&folio->page, false, NULL);
+ zswap_folio_swapin(folio);
+ return folio_file_page(folio, swp_offset(entry));
}
int init_swap_address_space(unsigned int type, unsigned long nr_pages)
@@ -806,7 +801,7 @@ static struct page *swap_vma_readahead(s
{
struct blk_plug plug;
struct swap_iocb *splug = NULL;
- struct page *page;
+ struct folio *folio;
pte_t *pte = NULL, pentry;
unsigned long addr;
swp_entry_t entry;
@@ -839,18 +834,18 @@ static struct page *swap_vma_readahead(s
continue;
pte_unmap(pte);
pte = NULL;
- page = __read_swap_cache_async(entry, gfp_mask, mpol, ilx,
+ folio = __read_swap_cache_async(entry, gfp_mask, mpol, ilx,
&page_allocated, false);
- if (!page)
+ if (!folio)
continue;
if (page_allocated) {
- swap_readpage(page, false, &splug);
+ swap_readpage(&folio->page, false, &splug);
if (i != ra_info.offset) {
- SetPageReadahead(page);
+ folio_set_readahead(folio);
count_vm_event(SWAP_RA);
}
}
- put_page(page);
+ folio_put(folio);
}
if (pte)
pte_unmap(pte);
@@ -858,13 +853,13 @@ static struct page *swap_vma_readahead(s
swap_read_unplug(splug);
lru_add_drain();
skip:
- /* The page was likely read above, so no need for plugging here */
- page = __read_swap_cache_async(targ_entry, gfp_mask, mpol, targ_ilx,
+ /* The folio was likely read above, so no need for plugging here */
+ folio = __read_swap_cache_async(targ_entry, gfp_mask, mpol, targ_ilx,
&page_allocated, false);
if (unlikely(page_allocated))
- swap_readpage(page, false, NULL);
- zswap_page_swapin(page);
- return page;
+ swap_readpage(&folio->page, false, NULL);
+ zswap_folio_swapin(folio);
+ return folio_file_page(folio, swp_offset(entry));
}
/**
--- a/mm/zswap.c~mm-return-the-folio-from-__read_swap_cache_async
+++ a/mm/zswap.c
@@ -373,12 +373,12 @@ void zswap_lruvec_state_init(struct lruv
atomic_long_set(&lruvec->zswap_lruvec_state.nr_zswap_protected, 0);
}
-void zswap_page_swapin(struct page *page)
+void zswap_folio_swapin(struct folio *folio)
{
struct lruvec *lruvec;
- if (page) {
- lruvec = folio_lruvec(page_folio(page));
+ if (folio) {
+ lruvec = folio_lruvec(folio);
atomic_long_inc(&lruvec->zswap_lruvec_state.nr_zswap_protected);
}
}
@@ -1431,14 +1431,14 @@ static void __zswap_load(struct zswap_en
* writeback code
**********************************/
/*
- * Attempts to free an entry by adding a page to the swap cache,
- * decompressing the entry data into the page, and issuing a
- * bio write to write the page back to the swap device.
+ * Attempts to free an entry by adding a folio to the swap cache,
+ * decompressing the entry data into the folio, and issuing a
+ * bio write to write the folio back to the swap device.
*
- * This can be thought of as a "resumed writeback" of the page
+ * This can be thought of as a "resumed writeback" of the folio
* to the swap device. We are basically resuming the same swap
* writeback path that was intercepted with the zswap_store()
- * in the first place. After the page has been decompressed into
+ * in the first place. After the folio has been decompressed into
* the swap cache, the compressed version stored by zswap can be
* freed.
*/
@@ -1446,23 +1446,23 @@ static int zswap_writeback_entry(struct
struct zswap_tree *tree)
{
swp_entry_t swpentry = entry->swpentry;
- struct page *page;
+ struct folio *folio;
struct mempolicy *mpol;
bool page_was_allocated;
struct writeback_control wbc = {
.sync_mode = WB_SYNC_NONE,
};
- /* try to allocate swap cache page */
+ /* try to allocate swap cache folio */
mpol = get_task_policy(current);
- page = __read_swap_cache_async(swpentry, GFP_KERNEL, mpol,
+ folio = __read_swap_cache_async(swpentry, GFP_KERNEL, mpol,
NO_INTERLEAVE_INDEX, &page_was_allocated, true);
- if (!page)
+ if (!folio)
return -ENOMEM;
- /* Found an existing page, we raced with load/swapin */
+ /* Found an existing folio, we raced with load/swapin */
if (!page_was_allocated) {
- put_page(page);
+ folio_put(folio);
return -EEXIST;
}
@@ -1471,27 +1471,27 @@ static int zswap_writeback_entry(struct
* concurrent swapping to and from the slot. Verify that the
* swap entry hasn't been invalidated and recycled behind our
* backs (our zswap_entry reference doesn't prevent that), to
- * avoid overwriting a new swap page with old compressed data.
+ * avoid overwriting a new swap folio with old compressed data.
*/
spin_lock(&tree->lock);
if (zswap_rb_search(&tree->rbroot, swp_offset(entry->swpentry)) != entry) {
spin_unlock(&tree->lock);
- delete_from_swap_cache(page_folio(page));
+ delete_from_swap_cache(folio);
return -ENOMEM;
}
spin_unlock(&tree->lock);
- __zswap_load(entry, page);
+ __zswap_load(entry, &folio->page);
- /* page is up to date */
- SetPageUptodate(page);
+ /* folio is up to date */
+ folio_mark_uptodate(folio);
/* move it to the tail of the inactive list after end_writeback */
- SetPageReclaim(page);
+ folio_set_reclaim(folio);
/* start writeback */
- __swap_writepage(page, &wbc);
- put_page(page);
+ __swap_writepage(&folio->page, &wbc);
+ folio_put(folio);
return 0;
}
@@ -1637,7 +1637,7 @@ bool zswap_store(struct folio *folio)
dst = acomp_ctx->dstmem;
sg_init_table(&input, 1);
- sg_set_page(&input, page, PAGE_SIZE, 0);
+ sg_set_page(&input, &folio->page, PAGE_SIZE, 0);
sg_init_one(&output, dst, PAGE_SIZE);
acomp_request_set_params(acomp_ctx->req, &input, &output, PAGE_SIZE, dlen);
_
Patches currently in -mm which might be from willy@xxxxxxxxxxxxx are
buffer-return-bool-from-grow_dev_folio.patch
buffer-calculate-block-number-inside-folio_init_buffers.patch
buffer-fix-grow_buffers-for-block-size-page_size.patch
buffer-cast-block-to-loff_t-before-shifting-it.patch
buffer-fix-various-functions-for-block-size-page_size.patch
buffer-handle-large-folios-in-__block_write_begin_int.patch
buffer-fix-more-functions-for-block-size-page_size.patch
mm-convert-ksm_might_need_to_copy-to-work-on-folios.patch
mm-remove-pageanonexclusive-assertions-in-unuse_pte.patch
mm-convert-unuse_pte-to-use-a-folio-throughout.patch
mm-remove-some-calls-to-page_add_new_anon_rmap.patch
mm-remove-stale-example-from-comment.patch
mm-remove-references-to-page_add_new_anon_rmap-in-comments.patch
mm-convert-migrate_vma_insert_page-to-use-a-folio.patch
mm-convert-collapse_huge_page-to-use-a-folio.patch
mm-remove-page_add_new_anon_rmap-and-lru_cache_add_inactive_or_unevictable.patch
mm-return-the-folio-from-__read_swap_cache_async.patch
mm-pass-a-folio-to-__swap_writepage.patch
mm-pass-a-folio-to-swap_writepage_fs.patch
mm-pass-a-folio-to-swap_writepage_bdev_sync.patch
mm-pass-a-folio-to-swap_writepage_bdev_async.patch
mm-pass-a-folio-to-swap_readpage_fs.patch
mm-pass-a-folio-to-swap_readpage_bdev_sync.patch
mm-pass-a-folio-to-swap_readpage_bdev_async.patch
mm-convert-swap_page_sector-to-swap_folio_sector.patch
mm-convert-swap_readpage-to-swap_read_folio.patch
mm-remove-page_swap_info.patch
mm-return-a-folio-from-read_swap_cache_async.patch
mm-convert-swap_cluster_readahead-and-swap_vma_readahead-to-return-a-folio.patch
