3 files changed, 53 insertions, 27 deletions

diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index fcf77e1..89ba79f 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -2161,6 +2161,38 @@ static int bio_readpage_error(struct bio *failed_bio, struct page *page,
 
 /* lots and lots of room for performance fixes in the end_bio funcs */
 
+int end_extent_writepage(struct page *page, int err, u64 start, u64 end)
+{
+	int uptodate = (err == 0);
+	struct extent_io_tree *tree;
+	int ret;
+
+	tree = &BTRFS_I(page->mapping->host)->io_tree;
+
+	if (tree->ops && tree->ops->writepage_end_io_hook) {
+		ret = tree->ops->writepage_end_io_hook(page, start,
+					       end, NULL, uptodate);
+		if (ret)
+			uptodate = 0;
+	}
+
+	if (!uptodate && tree->ops &&
+	    tree->ops->writepage_io_failed_hook) {
+		ret = tree->ops->writepage_io_failed_hook(NULL, page,
+						 start, end, NULL);
+		/* Writeback already completed */
+		if (ret == 0)
+			return 1;
+	}
+
+	if (!uptodate) {
+		clear_extent_uptodate(tree, start, end, NULL, GFP_NOFS);
+		ClearPageUptodate(page);
+		SetPageError(page);
+	}
+	return 0;
+}
+
 /*
  * after a writepage IO is done, we need to:
  * clear the uptodate bits on error
@@ -2172,13 +2204,11 @@ static int bio_readpage_error(struct bio *failed_bio, struct page *page,
  */
 static void end_bio_extent_writepage(struct bio *bio, int err)
 {
-	int uptodate = err == 0;
 	struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1;
 	struct extent_io_tree *tree;
 	u64 start;
 	u64 end;
 	int whole_page;
-	int ret;
 
 	do {
 		struct page *page = bvec->bv_page;
@@ -2195,28 +2225,9 @@ static void end_bio_extent_writepage(struct bio *bio, int err)
 
 		if (--bvec >= bio->bi_io_vec)
 			prefetchw(&bvec->bv_page->flags);
-		if (tree->ops && tree->ops->writepage_end_io_hook) {
-			ret = tree->ops->writepage_end_io_hook(page, start,
-						       end, NULL, uptodate);
-			if (ret)
-				uptodate = 0;
-		}
-
-		if (!uptodate && tree->ops &&
-		    tree->ops->writepage_io_failed_hook) {
-			ret = tree->ops->writepage_io_failed_hook(bio, page,
-							 start, end, NULL);
-			if (ret == 0) {
-				uptodate = (err == 0);
-				continue;
-			}
-		}
 
-		if (!uptodate) {
-			clear_extent_uptodate(tree, start, end, NULL, GFP_NOFS);
-			ClearPageUptodate(page);
-			SetPageError(page);
-		}
+		if (end_extent_writepage(page, err, start, end))
+			continue;
 
 		if (whole_page)
 			end_page_writeback(page);
@@ -2818,8 +2829,12 @@ static int __extent_writepage(struct page *page, struct writeback_control *wbc,
 	if (tree->ops && tree->ops->writepage_start_hook) {
 		ret = tree->ops->writepage_start_hook(page, start,
 						      page_end);
-		if (ret == -EAGAIN) {
-			redirty_page_for_writepage(wbc, page);
+		if (ret) {
+			/* Fixup worker will requeue */
+			if (ret == -EBUSY)
+				wbc->pages_skipped++;
+			else
+				redirty_page_for_writepage(wbc, page);
 			update_nr_written(page, wbc, nr_written);
 			unlock_page(page);
 			ret = 0;
diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h
index bc6a042cb..cecc351 100644
--- a/fs/btrfs/extent_io.h
+++ b/fs/btrfs/extent_io.h
@@ -319,4 +319,5 @@ struct btrfs_mapping_tree;
 int repair_io_failure(struct btrfs_mapping_tree *map_tree, u64 start,
 			u64 length, u64 logical, struct page *page,
 			int mirror_num);
+int end_extent_writepage(struct page *page, int err, u64 start, u64 end);
 #endif
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 7405753..bf392e5 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -1555,6 +1555,7 @@ static void btrfs_writepage_fixup_worker(struct btrfs_work *work)
 	struct inode *inode;
 	u64 page_start;
 	u64 page_end;
+	int ret;
 
 	fixup = container_of(work, struct btrfs_writepage_fixup, work);
 	page = fixup->page;
@@ -1582,12 +1583,21 @@ again:
 				     page_end, &cached_state, GFP_NOFS);
 		unlock_page(page);
 		btrfs_start_ordered_extent(inode, ordered, 1);
+		btrfs_put_ordered_extent(ordered);
 		goto again;
 	}
 
-	BUG();
+	ret = btrfs_delalloc_reserve_space(inode, PAGE_CACHE_SIZE);
+	if (ret) {
+		mapping_set_error(page->mapping, ret);
+		end_extent_writepage(page, ret, page_start, page_end);
+		ClearPageChecked(page);
+		goto out;
+	 }
+
 	btrfs_set_extent_delalloc(inode, page_start, page_end, &cached_state);
 	ClearPageChecked(page);
+	set_page_dirty(page);
 out:
 	unlock_extent_cached(&BTRFS_I(inode)->io_tree, page_start, page_end,
 			     &cached_state, GFP_NOFS);
@@ -1630,7 +1640,7 @@ static int btrfs_writepage_start_hook(struct page *page, u64 start, u64 end)
 	fixup->work.func = btrfs_writepage_fixup_worker;
 	fixup->page = page;
 	btrfs_queue_worker(&root->fs_info->fixup_workers, &fixup->work);
-	return -EAGAIN;
+	return -EBUSY;
 }
 
 static int insert_reserved_file_extent(struct btrfs_trans_handle *trans,