Btrfs: Handle writeback under high memory pressure better

Signed-off-by: Chris Mason <chris.mason@oracle.com>

1 files changed, 12 insertions, 0 deletions

diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c
index a4e9096754fc..55f272c335c6 100644
--- a/fs/btrfs/extent_map.c
+++ b/fs/btrfs/extent_map.c
@@ -1861,13 +1861,25 @@ int extent_write_full_page(struct extent_map_tree *tree, struct page *page,
                           struct writeback_control *wbc)
 {
         int ret;
+        struct address_space *mapping = page->mapping;
         struct extent_page_data epd = {
                 .bio = NULL,
                 .tree = tree,
                 .get_extent = get_extent,
         };
+        struct writeback_control wbc_writepages = {
+                .bdi            = wbc->bdi,
+                .sync_mode      = WB_SYNC_NONE,
+                .older_than_this = NULL,
+                .nr_to_write    = 64,
+                .range_start    = page_offset(page) + PAGE_CACHE_SIZE,
+                .range_end      = (loff_t)-1,
+        };
+
 
         ret = __extent_writepage(page, wbc, &epd);
+
+        write_cache_pages(mapping, &wbc_writepages, __extent_writepage, &epd);
         if (epd.bio)
                 submit_one_bio(WRITE, epd.bio);
         return ret;