2024-03-05 09:15:16

by Gao Xiang

[permalink] [raw]
Subject: [PATCH 4/6] erofs: convert z_erofs_fill_bio_vec() to folios

Introduce a folio member to `struct z_erofs_bvec` and convert most
of z_erofs_fill_bio_vec() to folios, which is still straight-forward.

Signed-off-by: Gao Xiang <[email protected]>
---
fs/erofs/zdata.c | 71 ++++++++++++++++++++++++------------------------
1 file changed, 36 insertions(+), 35 deletions(-)

diff --git a/fs/erofs/zdata.c b/fs/erofs/zdata.c
index 75b05990b571..d78cc54a96f5 100644
--- a/fs/erofs/zdata.c
+++ b/fs/erofs/zdata.c
@@ -19,7 +19,10 @@
typedef void *z_erofs_next_pcluster_t;

struct z_erofs_bvec {
- struct page *page;
+ union {
+ struct page *page;
+ struct folio *folio;
+ };
int offset;
unsigned int end;
};
@@ -1420,33 +1423,32 @@ static void z_erofs_fill_bio_vec(struct bio_vec *bvec,
struct page *page;
int bs = i_blocksize(f->inode);

- /* Except for inplace pages, the entire page can be used for I/Os */
+ /* Except for inplace folios, the entire folio can be used for I/Os */
bvec->bv_offset = 0;
bvec->bv_len = PAGE_SIZE;
repeat:
spin_lock(&pcl->obj.lockref.lock);
zbv = pcl->compressed_bvecs[nr];
- page = zbv.page;
spin_unlock(&pcl->obj.lockref.lock);
- if (!page)
- goto out_allocpage;
+ if (!zbv.folio)
+ goto out_allocfolio;

- bvec->bv_page = page;
- DBG_BUGON(z_erofs_is_shortlived_page(page));
+ bvec->bv_page = &zbv.folio->page;
+ DBG_BUGON(z_erofs_is_shortlived_page(bvec->bv_page));
/*
- * Handle preallocated cached pages. We tried to allocate such pages
+ * Handle preallocated cached folios. We tried to allocate such folios
* without triggering direct reclaim. If allocation failed, inplace
- * file-backed pages will be used instead.
+ * file-backed folios will be used instead.
*/
- if (page->private == Z_EROFS_PREALLOCATED_PAGE) {
- set_page_private(page, 0);
+ if (zbv.folio->private == (void *)Z_EROFS_PREALLOCATED_PAGE) {
+ zbv.folio->private = 0;
tocache = true;
goto out_tocache;
}

- mapping = READ_ONCE(page->mapping);
+ mapping = READ_ONCE(zbv.folio->mapping);
/*
- * File-backed pages for inplace I/Os are all locked steady,
+ * File-backed folios for inplace I/Os are all locked steady,
* therefore it is impossible for `mapping` to be NULL.
*/
if (mapping && mapping != mc) {
@@ -1456,22 +1458,21 @@ static void z_erofs_fill_bio_vec(struct bio_vec *bvec,
return;
}

- lock_page(page);
- /* the cached page is still in managed cache */
- if (page->mapping == mc) {
+ folio_lock(zbv.folio);
+ if (zbv.folio->mapping == mc) {
/*
- * The cached page is still available but without a valid
- * `->private` pcluster hint. Let's reconnect them.
+ * The cached folio is still in managed cache but without
+ * a valid `->private` pcluster hint. Let's reconnect them.
*/
- if (!PagePrivate(page)) {
- /* compressed_bvecs[] already takes a ref */
- attach_page_private(page, pcl);
- put_page(page);
+ if (!folio_test_private(zbv.folio)) {
+ folio_attach_private(zbv.folio, pcl);
+ /* compressed_bvecs[] already takes a ref before */
+ folio_put(zbv.folio);
}

/* no need to submit if it is already up-to-date */
- if (PageUptodate(page)) {
- unlock_page(page);
+ if (folio_test_uptodate(zbv.folio)) {
+ folio_unlock(zbv.folio);
bvec->bv_page = NULL;
}
return;
@@ -1481,32 +1482,32 @@ static void z_erofs_fill_bio_vec(struct bio_vec *bvec,
* It has been truncated, so it's unsafe to reuse this one. Let's
* allocate a new page for compressed data.
*/
- DBG_BUGON(page->mapping);
+ DBG_BUGON(zbv.folio->mapping);
tocache = true;
- unlock_page(page);
- put_page(page);
-out_allocpage:
+ folio_unlock(zbv.folio);
+ folio_put(zbv.folio);
+out_allocfolio:
page = erofs_allocpage(&f->pagepool, gfp | __GFP_NOFAIL);
spin_lock(&pcl->obj.lockref.lock);
- if (pcl->compressed_bvecs[nr].page) {
+ if (pcl->compressed_bvecs[nr].folio) {
erofs_pagepool_add(&f->pagepool, page);
spin_unlock(&pcl->obj.lockref.lock);
cond_resched();
goto repeat;
}
- pcl->compressed_bvecs[nr].page = page;
+ pcl->compressed_bvecs[nr].folio = zbv.folio = page_folio(page);
spin_unlock(&pcl->obj.lockref.lock);
bvec->bv_page = page;
out_tocache:
if (!tocache || bs != PAGE_SIZE ||
- add_to_page_cache_lru(page, mc, pcl->obj.index + nr, gfp)) {
- /* turn into a temporary shortlived page (1 ref) */
- set_page_private(page, Z_EROFS_SHORTLIVED_PAGE);
+ filemap_add_folio(mc, zbv.folio, pcl->obj.index + nr, gfp)) {
+ /* turn into a temporary shortlived folio (1 ref) */
+ zbv.folio->private = (void *)Z_EROFS_SHORTLIVED_PAGE;
return;
}
- attach_page_private(page, pcl);
+ folio_attach_private(zbv.folio, pcl);
/* drop a refcount added by allocpage (then 2 refs in total here) */
- put_page(page);
+ folio_put(zbv.folio);
}

static struct z_erofs_decompressqueue *jobqueue_init(struct super_block *sb,
--
2.39.3



2024-03-10 01:07:33

by Chao Yu

[permalink] [raw]
Subject: Re: [PATCH 4/6] erofs: convert z_erofs_fill_bio_vec() to folios

On 2024/3/5 17:14, Gao Xiang wrote:
> Introduce a folio member to `struct z_erofs_bvec` and convert most
> of z_erofs_fill_bio_vec() to folios, which is still straight-forward.
>
> Signed-off-by: Gao Xiang <[email protected]>

Reviewed-by: Chao Yu <[email protected]>

Thanks,