The logic in wbc_to_tag() is widely used in file systems, so modify this
function to be extern and use it in file systems.

This patch has only passed compilation tests, but it should be fine.

Signed-off-by: Julian Sun <sunjunchao@bytedance.com>
---
 fs/btrfs/extent_io.c      | 5 +----
 fs/ceph/addr.c            | 6 +-----
 fs/ext4/inode.c           | 5 +----
 fs/f2fs/data.c            | 5 +----
 fs/gfs2/aops.c            | 5 +----
 include/linux/writeback.h | 1 +
 mm/page-writeback.c       | 2 +-
 7 files changed, 7 insertions(+), 22 deletions(-)

diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index b21cb72835cc..0fea58287175 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -2390,10 +2390,7 @@ static int extent_write_cache_pages(struct address_space *mapping,
 			       &BTRFS_I(inode)->runtime_flags))
 		wbc->tagged_writepages = 1;
 
-	if (wbc->sync_mode == WB_SYNC_ALL || wbc->tagged_writepages)
-		tag = PAGECACHE_TAG_TOWRITE;
-	else
-		tag = PAGECACHE_TAG_DIRTY;
+	tag = wbc_to_tag(wbc);
 retry:
 	if (wbc->sync_mode == WB_SYNC_ALL || wbc->tagged_writepages)
 		tag_pages_for_writeback(mapping, index, end);
diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c
index 322ed268f14a..63b75d214210 100644
--- a/fs/ceph/addr.c
+++ b/fs/ceph/addr.c
@@ -1045,11 +1045,7 @@ void ceph_init_writeback_ctl(struct address_space *mapping,
 	ceph_wbc->index = ceph_wbc->start_index;
 	ceph_wbc->end = -1;
 
-	if (wbc->sync_mode == WB_SYNC_ALL || wbc->tagged_writepages) {
-		ceph_wbc->tag = PAGECACHE_TAG_TOWRITE;
-	} else {
-		ceph_wbc->tag = PAGECACHE_TAG_DIRTY;
-	}
+	ceph_wbc->tag = wbc_to_tag(wbc);
 
 	ceph_wbc->op_idx = -1;
 	ceph_wbc->num_ops = 0;
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 5b7a15db4953..196eba7fa39c 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -2619,10 +2619,7 @@ static int mpage_prepare_extent_to_map(struct mpage_da_data *mpd)
 	handle_t *handle = NULL;
 	int bpp = ext4_journal_blocks_per_folio(mpd->inode);
 
-	if (mpd->wbc->sync_mode == WB_SYNC_ALL || mpd->wbc->tagged_writepages)
-		tag = PAGECACHE_TAG_TOWRITE;
-	else
-		tag = PAGECACHE_TAG_DIRTY;
+	tag = wbc_to_tag(mpd->wbc);
 
 	mpd->map.m_len = 0;
 	mpd->next_pos = mpd->start_pos;
diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index 7961e0ddfca3..101e962845db 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -3003,10 +3003,7 @@ static int f2fs_write_cache_pages(struct address_space *mapping,
 		if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX)
 			range_whole = 1;
 	}
-	if (wbc->sync_mode == WB_SYNC_ALL || wbc->tagged_writepages)
-		tag = PAGECACHE_TAG_TOWRITE;
-	else
-		tag = PAGECACHE_TAG_DIRTY;
+	tag = wbc_to_tag(wbc);
 retry:
 	retry = 0;
 	if (wbc->sync_mode == WB_SYNC_ALL || wbc->tagged_writepages)
diff --git a/fs/gfs2/aops.c b/fs/gfs2/aops.c
index 47d74afd63ac..12394fc5dd29 100644
--- a/fs/gfs2/aops.c
+++ b/fs/gfs2/aops.c
@@ -311,10 +311,7 @@ static int gfs2_write_cache_jdata(struct address_space *mapping,
 			range_whole = 1;
 		cycled = 1; /* ignore range_cyclic tests */
 	}
-	if (wbc->sync_mode == WB_SYNC_ALL || wbc->tagged_writepages)
-		tag = PAGECACHE_TAG_TOWRITE;
-	else
-		tag = PAGECACHE_TAG_DIRTY;
+	tag = wbc_to_tag(wbc);
 
 retry:
 	if (wbc->sync_mode == WB_SYNC_ALL || wbc->tagged_writepages)
diff --git a/include/linux/writeback.h b/include/linux/writeback.h
index a2848d731a46..884811596e10 100644
--- a/include/linux/writeback.h
+++ b/include/linux/writeback.h
@@ -370,6 +370,7 @@ int do_writepages(struct address_space *mapping, struct writeback_control *wbc);
 void writeback_set_ratelimit(void);
 void tag_pages_for_writeback(struct address_space *mapping,
 			     pgoff_t start, pgoff_t end);
+xa_mark_t wbc_to_tag(struct writeback_control *wbc);
 
 bool filemap_dirty_folio(struct address_space *mapping, struct folio *folio);
 bool folio_redirty_for_writepage(struct writeback_control *, struct folio *);
diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index 3e248d1c3969..243808e19445 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -2434,7 +2434,7 @@ static bool folio_prepare_writeback(struct address_space *mapping,
 	return true;
 }
 
-static xa_mark_t wbc_to_tag(struct writeback_control *wbc)
+xa_mark_t wbc_to_tag(struct writeback_control *wbc)
 {
 	if (wbc->sync_mode == WB_SYNC_ALL || wbc->tagged_writepages)
 		return PAGECACHE_TAG_TOWRITE;
-- 
2.39.5