[PATCH 16/23] f2fs: Convert f2fs_sync_meta_pages() to use filemap_get_folios_tag()

Vishal Moola (Oracle)
2022-09-01T22:06:51Z

Convert function to use folios. This is in preparation for the removal
of find_get_pages_range_tag().

Initially the function was checking if the previous page index is truly the
previous page i.e. 1 index behind the current page. To convert to folios and
maintain this check we need to make the check
folio->index != prev + folio_nr_pages(previous folio) since we don't know
how many pages are in a folio.

At index i == 0 the check is guaranteed to succeed, so to workaround indexing
bounds we can simply ignore the check for that specific index. This makes the
initial assignment of prev trivial, so I removed that as well.

Also modified a comment in commit_checkpoint for consistency.

Signed-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>
---
fs/f2fs/checkpoint.c | 49 +++++++++++++++++++++++---------------------
1 file changed, 26 insertions(+), 23 deletions(-)

diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c
index 8259e0fa97e1..9f6694f7d723 100644
--- a/fs/f2fs/checkpoint.c
+++ b/fs/f2fs/checkpoint.c
@@ -377,59 +377,62 @@ long f2fs_sync_meta_pages(struct f2fs_sb_info *sbi, enum page_type type,
{
struct address_space *mapping = META_MAPPING(sbi);
pgoff_t index = 0, prev = ULONG_MAX;
- struct pagevec pvec;
+ struct folio_batch fbatch;
long nwritten = 0;
- int nr_pages;
+ int nr_folios;
struct writeback_control wbc = {
.for_reclaim = 0,
};
struct blk_plug plug;

- pagevec_init(&pvec);
+ folio_batch_init(&fbatch);

blk_start_plug(&plug);

- while ((nr_pages = pagevec_lookup_tag(&pvec, mapping, &index,
- PAGECACHE_TAG_DIRTY))) {
+ while ((nr_folios = filemap_get_folios_tag(mapping, &index,
+ (pgoff_t)-1,
+ PAGECACHE_TAG_DIRTY, &fbatch))) {
int i;

- for (i = 0; i < nr_pages; i++) {
- struct page *page = pvec.pages[i];
+ for (i = 0; i < nr_folios; i++) {
+ struct folio *folio = fbatch.folios[i];

- if (prev == ULONG_MAX)
- prev = page->index - 1;
- if (nr_to_write != LONG_MAX && page->index != prev + 1) {
- pagevec_release(&pvec);
+ if (nr_to_write != LONG_MAX && i != 0 &&
+ folio->index != prev +
+ folio_nr_pages(fbatch.folios[i-1])) {
+ folio_batch_release(&fbatch);
goto stop;
}

- lock_page(page);
+ folio_lock(folio);

- if (unlikely(page->mapping != mapping)) {
+ if (unlikely(folio->mapping != mapping)) {
continue_unlock:
- unlock_page(page);
+ folio_unlock(folio);
continue;
}
- if (!PageDirty(page)) {
+ if (!folio_test_dirty(folio)) {
/* someone wrote it for us */
goto continue_unlock;
}

- f2fs_wait_on_page_writeback(page, META, true, true);
+ f2fs_wait_on_page_writeback(&folio->page, META,
+ true, true);

- if (!clear_page_dirty_for_io(page))
+ if (!folio_clear_dirty_for_io(folio))
goto continue_unlock;

- if (__f2fs_write_meta_page(page, &wbc, io_type)) {
- unlock_page(page);
+ if (__f2fs_write_meta_page(&folio->page, &wbc,
+ io_type)) {
+ folio_unlock(folio);
break;
}
- nwritten++;
- prev = page->index;
+ nwritten += folio_nr_pages(folio);
+ prev = folio->index;
if (unlikely(nwritten >= nr_to_write))
break;
}
- pagevec_release(&pvec);
+ folio_batch_release(&fbatch);
cond_resched();
}
stop:
@@ -1381,7 +1384,7 @@ static void commit_checkpoint(struct f2fs_sb_info *sbi,
};

/*
- * pagevec_lookup_tag and lock_page again will take
+ * filemap_get_folios_tag and lock_page again will take
* some extra time. Therefore, f2fs_update_meta_pages and
* f2fs_sync_meta_pages are combined in this function.
*/
--
2.36.1