Btrfs: Update metadata reservation for delayed allocation

Introduce metadata reservation context for delayed allocation
and update various related functions.

This patch also introduces EXTENT_FIRST_DELALLOC control bit for
set/clear_extent_bit. It tells set/clear_bit_hook whether they
are processing the first extent_state with EXTENT_DELALLOC bit
set. This change is important if set/clear_extent_bit involves
multiple extent_state.

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

1 files changed, 5 insertions, 3 deletions

diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h
index bbab4813646f..86f10dc791d9 100644
--- a/fs/btrfs/extent_io.h
+++ b/fs/btrfs/extent_io.h
@@ -16,7 +16,9 @@
 #define EXTENT_BOUNDARY (1 << 9)
 #define EXTENT_NODATASUM (1 << 10)
 #define EXTENT_DO_ACCOUNTING (1 << 11)
+#define EXTENT_FIRST_DELALLOC (1 << 12)
 #define EXTENT_IOBITS (EXTENT_LOCKED | EXTENT_WRITEBACK)
+#define EXTENT_CTLBITS (EXTENT_DO_ACCOUNTING | EXTENT_FIRST_DELALLOC)
 
 /* flags for bio submission */
 #define EXTENT_BIO_COMPRESSED 1
@@ -69,10 +71,10 @@ struct extent_io_ops {
                                     struct extent_state *state);
         int (*writepage_end_io_hook)(struct page *page, u64 start, u64 end,
                                       struct extent_state *state, int uptodate);
-        int (*set_bit_hook)(struct inode *inode, u64 start, u64 end,
-                            unsigned long old, unsigned long bits);
+        int (*set_bit_hook)(struct inode *inode, struct extent_state *state,
+                            int *bits);
         int (*clear_bit_hook)(struct inode *inode, struct extent_state *state,
-                              unsigned long bits);
+                              int *bits);
         int (*merge_extent_hook)(struct inode *inode,
                                  struct extent_state *new,
                                  struct extent_state *other);