[RFC PATCH] f2fs: Convert f2fs_write_cache_pages() to use filemap_get_folios_tag()

From: Vishal Moola (Oracle)
Date: Mon Dec 12 2022 - 14:15:42 EST


Converted the function to use a folio_batch instead of pagevec. This is in
preparation for the removal of find_get_pages_range_tag().

Also modified f2fs_all_cluster_page_ready to take in a folio_batch instead
of pagevec. This does NOT support large folios. The function currently
only utilizes folios of size 1 so this shouldn't cause any issues right
now.

This version of the patch limits the number of pages fetched to
F2FS_ONSTACK_PAGES. If that ever happens, update the start index here
since filemap_get_folios_tag() updates the index to be after the last
found folio, not necessarily the last used page.

Signed-off-by: Vishal Moola (Oracle) <vishal.moola@xxxxxxxxx>
---

Let me know if you prefer this version and I'll include it in v5
of the patch series when I rebase it after the merge window.

---
fs/f2fs/data.c | 86 ++++++++++++++++++++++++++++++++++----------------
1 file changed, 59 insertions(+), 27 deletions(-)

diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index a71e818cd67b..1703e353f0e0 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -2939,6 +2939,7 @@ static int f2fs_write_cache_pages(struct address_space *mapping,
int ret = 0;
int done = 0, retry = 0;
struct page *pages[F2FS_ONSTACK_PAGES];
+ struct folio_batch fbatch;
struct f2fs_sb_info *sbi = F2FS_M_SB(mapping);
struct bio *bio = NULL;
sector_t last_block;
@@ -2959,6 +2960,7 @@ static int f2fs_write_cache_pages(struct address_space *mapping,
.private = NULL,
};
#endif
+ int nr_folios, p, idx;
int nr_pages;
pgoff_t index;
pgoff_t end; /* Inclusive */
@@ -2969,6 +2971,8 @@ static int f2fs_write_cache_pages(struct address_space *mapping,
int submitted = 0;
int i;

+ folio_batch_init(&fbatch);
+
if (get_dirty_pages(mapping->host) <=
SM_I(F2FS_M_SB(mapping))->min_hot_blocks)
set_inode_flag(mapping->host, FI_HOT_DATA);
@@ -2994,13 +2998,38 @@ static int f2fs_write_cache_pages(struct address_space *mapping,
tag_pages_for_writeback(mapping, index, end);
done_index = index;
while (!done && !retry && (index <= end)) {
- nr_pages = find_get_pages_range_tag(mapping, &index, end,
- tag, F2FS_ONSTACK_PAGES, pages);
- if (nr_pages == 0)
+ nr_pages = 0;
+again:
+ nr_folios = filemap_get_folios_tag(mapping, &index, end,
+ tag, &fbatch);
+ if (nr_folios == 0) {
+ if (nr_pages)
+ goto write;
break;
+ }

+ for (i = 0; i < nr_folios; i++) {
+ struct folio* folio = fbatch.folios[i];
+
+ idx = 0;
+ p = folio_nr_pages(folio);
+add_more:
+ pages[nr_pages] = folio_page(folio,idx);
+ folio_ref_inc(folio);
+ if (++nr_pages == F2FS_ONSTACK_PAGES) {
+ index = folio->index + idx + 1;
+ folio_batch_release(&fbatch);
+ goto write;
+ }
+ if (++idx < p)
+ goto add_more;
+ }
+ folio_batch_release(&fbatch);
+ goto again;
+write:
for (i = 0; i < nr_pages; i++) {
struct page *page = pages[i];
+ struct folio *folio = page_folio(page);
bool need_readd;
readd:
need_readd = false;
@@ -3017,7 +3046,7 @@ static int f2fs_write_cache_pages(struct address_space *mapping,
}

if (!f2fs_cluster_can_merge_page(&cc,
- page->index)) {
+ folio->index)) {
ret = f2fs_write_multi_pages(&cc,
&submitted, wbc, io_type);
if (!ret)
@@ -3026,27 +3055,28 @@ static int f2fs_write_cache_pages(struct address_space *mapping,
}

if (unlikely(f2fs_cp_error(sbi)))
- goto lock_page;
+ goto lock_folio;

if (!f2fs_cluster_is_empty(&cc))
- goto lock_page;
+ goto lock_folio;

if (f2fs_all_cluster_page_ready(&cc,
pages, i, nr_pages, true))
- goto lock_page;
+ goto lock_folio;

ret2 = f2fs_prepare_compress_overwrite(
inode, &pagep,
- page->index, &fsdata);
+ folio->index, &fsdata);
if (ret2 < 0) {
ret = ret2;
done = 1;
break;
} else if (ret2 &&
(!f2fs_compress_write_end(inode,
- fsdata, page->index, 1) ||
+ fsdata, folio->index, 1) ||
!f2fs_all_cluster_page_ready(&cc,
- pages, i, nr_pages, false))) {
+ pages, i, nr_pages,
+ false))) {
retry = 1;
break;
}
@@ -3059,46 +3089,47 @@ static int f2fs_write_cache_pages(struct address_space *mapping,
break;
}
#ifdef CONFIG_F2FS_FS_COMPRESSION
-lock_page:
+lock_folio:
#endif
- done_index = page->index;
+ done_index = folio->index;
retry_write:
- 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;
}

- if (PageWriteback(page)) {
+ if (folio_test_writeback(folio)) {
if (wbc->sync_mode != WB_SYNC_NONE)
- f2fs_wait_on_page_writeback(page,
+ f2fs_wait_on_page_writeback(
+ &folio->page,
DATA, true, true);
else
goto continue_unlock;
}

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

#ifdef CONFIG_F2FS_FS_COMPRESSION
if (f2fs_compressed_file(inode)) {
- get_page(page);
- f2fs_compress_ctx_add_page(&cc, page);
+ folio_get(folio);
+ f2fs_compress_ctx_add_page(&cc, &folio->page);
continue;
}
#endif
- ret = f2fs_write_single_data_page(page, &submitted,
- &bio, &last_block, wbc, io_type,
- 0, true);
+ ret = f2fs_write_single_data_page(&folio->page,
+ &submitted, &bio, &last_block,
+ wbc, io_type, 0, true);
if (ret == AOP_WRITEPAGE_ACTIVATE)
- unlock_page(page);
+ folio_unlock(folio);
#ifdef CONFIG_F2FS_FS_COMPRESSION
result:
#endif
@@ -3122,7 +3153,8 @@ static int f2fs_write_cache_pages(struct address_space *mapping,
}
goto next;
}
- done_index = page->index + 1;
+ done_index = folio->index +
+ folio_nr_pages(folio);
done = 1;
break;
}
@@ -3136,7 +3168,7 @@ static int f2fs_write_cache_pages(struct address_space *mapping,
if (need_readd)
goto readd;
}
- release_pages(pages, nr_pages);
+ release_pages(pages,nr_pages);
cond_resched();
}
#ifdef CONFIG_F2FS_FS_COMPRESSION
--
2.38.1