1 files changed, 45 insertions, 21 deletions

diff --git a/fs/nilfs2/page.c b/fs/nilfs2/page.c
index 5436eb0424bd..806b056d2260 100644
--- a/fs/nilfs2/page.c
+++ b/fs/nilfs2/page.c
@@ -39,7 +39,6 @@ static struct buffer_head *__nilfs_get_folio_block(struct folio *folio,
 	first_block = (unsigned long)index << (PAGE_SHIFT - blkbits);
 	bh = get_nth_bh(bh, block - first_block);
 
-	touch_buffer(bh);
 	wait_on_buffer(bh);
 	return bh;
 }
@@ -64,6 +63,7 @@ struct buffer_head *nilfs_grab_buffer(struct inode *inode,
 		folio_put(folio);
 		return NULL;
 	}
+	bh->b_bdev = inode->i_sb->s_bdev;
 	return bh;
 }
 
@@ -99,16 +99,16 @@ void nilfs_forget_buffer(struct buffer_head *bh)
  */
 void nilfs_copy_buffer(struct buffer_head *dbh, struct buffer_head *sbh)
 {
-	void *kaddr0, *kaddr1;
+	void *saddr, *daddr;
 	unsigned long bits;
-	struct page *spage = sbh->b_page, *dpage = dbh->b_page;
+	struct folio *sfolio = sbh->b_folio, *dfolio = dbh->b_folio;
 	struct buffer_head *bh;
 
-	kaddr0 = kmap_local_page(spage);
-	kaddr1 = kmap_local_page(dpage);
-	memcpy(kaddr1 + bh_offset(dbh), kaddr0 + bh_offset(sbh), sbh->b_size);
-	kunmap_local(kaddr1);
-	kunmap_local(kaddr0);
+	saddr = kmap_local_folio(sfolio, bh_offset(sbh));
+	daddr = kmap_local_folio(dfolio, bh_offset(dbh));
+	memcpy(daddr, saddr, sbh->b_size);
+	kunmap_local(daddr);
+	kunmap_local(saddr);
 
 	dbh->b_state = sbh->b_state & NILFS_BUFFER_INHERENT_BITS;
 	dbh->b_blocknr = sbh->b_blocknr;
@@ -122,21 +122,20 @@ void nilfs_copy_buffer(struct buffer_head *dbh, struct buffer_head *sbh)
 		unlock_buffer(bh);
 	}
 	if (bits & BIT(BH_Uptodate))
-		SetPageUptodate(dpage);
+		folio_mark_uptodate(dfolio);
 	else
-		ClearPageUptodate(dpage);
+		folio_clear_uptodate(dfolio);
 	if (bits & BIT(BH_Mapped))
-		SetPageMappedToDisk(dpage);
+		folio_set_mappedtodisk(dfolio);
 	else
-		ClearPageMappedToDisk(dpage);
+		folio_clear_mappedtodisk(dfolio);
 }
 
 /**
  * nilfs_folio_buffers_clean - Check if a folio has dirty buffers or not.
  * @folio: Folio to be checked.
  *
- * nilfs_folio_buffers_clean() returns false if the folio has dirty buffers.
- * Otherwise, it returns true.
+ * Return: false if the folio has dirty buffers, true otherwise.
  */
 bool nilfs_folio_buffers_clean(struct folio *folio)
 {
@@ -392,6 +391,11 @@ void nilfs_clear_dirty_pages(struct address_space *mapping)
 /**
  * nilfs_clear_folio_dirty - discard dirty folio
  * @folio: dirty folio that will be discarded
+ *
+ * nilfs_clear_folio_dirty() clears working states including dirty state for
+ * the folio and its buffers.  If the folio has buffers, clear only if it is
+ * confirmed that none of the buffer heads are busy (none have valid
+ * references and none are locked).
  */
 void nilfs_clear_folio_dirty(struct folio *folio)
 {
@@ -399,9 +403,6 @@ void nilfs_clear_folio_dirty(struct folio *folio)
 
 	BUG_ON(!folio_test_locked(folio));
 
-	folio_clear_uptodate(folio);
-	folio_clear_mappedtodisk(folio);
-
 	head = folio_buffers(folio);
 	if (head) {
 		const unsigned long clear_bits =
@@ -409,6 +410,25 @@ void nilfs_clear_folio_dirty(struct folio *folio)
 			 BIT(BH_Async_Write) | BIT(BH_NILFS_Volatile) |
 			 BIT(BH_NILFS_Checked) | BIT(BH_NILFS_Redirected) |
 			 BIT(BH_Delay));
+		bool busy, invalidated = false;
+
+recheck_buffers:
+		busy = false;
+		bh = head;
+		do {
+			if (atomic_read(&bh->b_count) | buffer_locked(bh)) {
+				busy = true;
+				break;
+			}
+		} while (bh = bh->b_this_page, bh != head);
+
+		if (busy) {
+			if (invalidated)
+				return;
+			invalidate_bh_lrus();
+			invalidated = true;
+			goto recheck_buffers;
+		}
 
 		bh = head;
 		do {
@@ -418,17 +438,20 @@ void nilfs_clear_folio_dirty(struct folio *folio)
 		} while (bh = bh->b_this_page, bh != head);
 	}
 
+	folio_clear_uptodate(folio);
+	folio_clear_mappedtodisk(folio);
+	folio_clear_checked(folio);
 	__nilfs_clear_folio_dirty(folio);
 }
 
-unsigned int nilfs_page_count_clean_buffers(struct page *page,
+unsigned int nilfs_page_count_clean_buffers(struct folio *folio,
 					    unsigned int from, unsigned int to)
 {
 	unsigned int block_start, block_end;
 	struct buffer_head *bh, *head;
 	unsigned int nc = 0;
 
-	for (bh = head = page_buffers(page), block_start = 0;
+	for (bh = head = folio_buffers(folio), block_start = 0;
 	     bh != head || !block_start;
 	     block_start = block_end, bh = bh->b_this_page) {
 		block_end = block_start + bh->b_size;
@@ -476,8 +499,9 @@ void __nilfs_clear_folio_dirty(struct folio *folio)
  * This function searches an extent of buffers marked "delayed" which
  * starts from a block offset equal to or larger than @start_blk.  If
  * such an extent was found, this will store the start offset in
- * @blkoff and return its length in blocks.  Otherwise, zero is
- * returned.
+ * @blkoff and return its length in blocks.
+ *
+ * Return: Length in blocks of found extent, 0 otherwise.
  */
 unsigned long nilfs_find_uncommitted_extent(struct inode *inode,
 					    sector_t start_blk,