Btrfs: Handle write errors on raid1 and raid10

When duplicate copies exist, writes are allowed to fail to one of those
copies.  This changeset includes a few changes that allow the FS to
continue even when some IOs fail.

It also adds verification of the parent generation number for btree blocks.
This generation is stored in the pointer to a block, and it ensures
that missed writes to are detected.

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

1 files changed, 6 insertions, 1 deletions

diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h
index e48346147514..f1960dafaa19 100644
--- a/fs/btrfs/extent_io.h
+++ b/fs/btrfs/extent_io.h
@@ -36,9 +36,12 @@ struct extent_io_ops {
         int (*readpage_io_failed_hook)(struct bio *bio, struct page *page,
                                        u64 start, u64 end,
                                        struct extent_state *state);
+        int (*writepage_io_failed_hook)(struct bio *bio, struct page *page,
+                                        u64 start, u64 end,
+                                       struct extent_state *state);
         int (*readpage_end_io_hook)(struct page *page, u64 start, u64 end,
                                     struct extent_state *state);
-        void (*writepage_end_io_hook)(struct page *page, u64 start, u64 end,
+        int (*writepage_end_io_hook)(struct page *page, u64 start, u64 end,
                                       struct extent_state *state);
         int (*set_bit_hook)(struct inode *inode, u64 start, u64 end,
                             unsigned long old, unsigned long bits);
@@ -212,6 +215,8 @@ int set_extent_buffer_dirty(struct extent_io_tree *tree,
                              struct extent_buffer *eb);
 int set_extent_buffer_uptodate(struct extent_io_tree *tree,
                                struct extent_buffer *eb);
+int clear_extent_buffer_uptodate(struct extent_io_tree *tree,
+                                struct extent_buffer *eb);
 int extent_buffer_uptodate(struct extent_io_tree *tree,
                            struct extent_buffer *eb);
 int map_extent_buffer(struct extent_buffer *eb, unsigned long offset,