ath9k: reduce the number of functions that access the tx descriptor

[pandora-kernel.git] / fs / btrfs / extent_io.h

diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h
index a11a92e..21a7ca9 100644 (file)
--- a/fs/btrfs/extent_io.h
+++ b/fs/btrfs/extent_io.h
@@ -120,8 +120,6 @@ struct extent_state {
 struct extent_buffer {
        u64 start;
        unsigned long len;
-       char *map_token;
-       char *kaddr;
        unsigned long map_start;
        unsigned long map_len;
        struct page *first_page;
@@ -130,14 +128,26 @@ struct extent_buffer {
        struct rcu_head rcu_head;
        atomic_t refs;
 
-       /* the spinlock is used to protect most operations */
-       spinlock_t lock;
+       /* count of read lock holders on the extent buffer */
+       atomic_t write_locks;
+       atomic_t read_locks;
+       atomic_t blocking_writers;
+       atomic_t blocking_readers;
+       atomic_t spinning_readers;
+       atomic_t spinning_writers;
+
+       /* protects write locks */
+       rwlock_t lock;
 
-       /*
-        * when we keep the lock held while blocking, waiters go onto
-        * the wq
+       /* readers use lock_wq while they wait for the write
+        * lock holders to unlock
         */
-       wait_queue_head_t lock_wq;
+       wait_queue_head_t write_lock_wq;
+
+       /* writers use read_lock_wq while they wait for readers
+        * to unlock
+        */
+       wait_queue_head_t read_lock_wq;
 };
 
 static inline void extent_set_compress_type(unsigned long *bio_flags,
@@ -279,15 +289,10 @@ int clear_extent_buffer_uptodate(struct extent_io_tree *tree,
 int extent_buffer_uptodate(struct extent_io_tree *tree,
                           struct extent_buffer *eb,
                           struct extent_state *cached_state);
-int map_extent_buffer(struct extent_buffer *eb, unsigned long offset,
-                     unsigned long min_len, char **token, char **map,
-                     unsigned long *map_start,
-                     unsigned long *map_len, int km);
 int map_private_extent_buffer(struct extent_buffer *eb, unsigned long offset,
-                     unsigned long min_len, char **token, char **map,
+                     unsigned long min_len, char **map,
                      unsigned long *map_start,
-                     unsigned long *map_len, int km);
-void unmap_extent_buffer(struct extent_buffer *eb, char *token, int km);
+                     unsigned long *map_len);
 int extent_range_uptodate(struct extent_io_tree *tree,
                          u64 start, u64 end);
 int extent_clear_unlock_delalloc(struct inode *inode,