ocfs2: Make the ocfs2_caching_info structure self-contained.

We want to use the ocfs2_caching_info structure in places that are not
inodes.  To do that, it can no longer rely on referencing the inode
directly.

This patch moves the flags to ocfs2_caching_info->ci_flags, stores
pointers to the parent's locks on the ocfs2_caching_info, and renames
the constants and flags to reflect its independant state.
Signed-off-by: Joel Becker <joel.becker@oracle.com>

fs/ocfs2/inode.c

@@ -1118,7 +1118,8 @@ void ocfs2_clear_inode(struct inode *inode)
 			"Clear inode of %llu, inode has %u cache items\n",
 			(unsigned long long)oi->ip_blkno, oi->ip_metadata_cache.ci_num_cached);
 
-	mlog_bug_on_msg(!(oi->ip_flags & OCFS2_INODE_CACHE_INLINE),
+	mlog_bug_on_msg(!(oi->ip_metadata_cache.ci_flags &
+			  OCFS2_CACHE_FL_INLINE),
 			"Clear inode of %llu, inode has a bad flag\n",
 			(unsigned long long)oi->ip_blkno);
 
@@ -1145,7 +1146,7 @@ void ocfs2_clear_inode(struct inode *inode)
 			(unsigned long long)oi->ip_blkno, oi->ip_open_count);
 
 	/* Clear all other flags. */
-	oi->ip_flags = OCFS2_INODE_CACHE_INLINE;
+	oi->ip_flags = 0;
 	oi->ip_created_trans = 0;
 	oi->ip_last_trans = 0;
 	oi->ip_dir_start_lookup = 0;

fs/ocfs2/inode.h

@@ -106,8 +106,6 @@ struct ocfs2_inode_info
 #define OCFS2_INODE_MAYBE_ORPHANED	0x00000020
 /* Does someone have the file open O_DIRECT */
 #define OCFS2_INODE_OPEN_DIRECT		0x00000040
-/* Indicates that the metadata cache should be used as an array. */
-#define OCFS2_INODE_CACHE_INLINE	0x00000080
 
 static inline struct ocfs2_inode_info *OCFS2_I(struct inode *inode)
 {

fs/ocfs2/ocfs2.h

@@ -51,17 +51,36 @@
 /* For struct ocfs2_blockcheck_stats */
 #include "blockcheck.h"
 
+
+/* Caching of metadata buffers */
+
 /* Most user visible OCFS2 inodes will have very few pieces of
  * metadata, but larger files (including bitmaps, etc) must be taken
  * into account when designing an access scheme. We allow a small
  * amount of inlined blocks to be stored on an array and grow the
  * structure into a rb tree when necessary. */
-#define OCFS2_INODE_MAX_CACHE_ARRAY 2
+#define OCFS2_CACHE_INFO_MAX_ARRAY 2
+
+/* Flags for ocfs2_caching_info */
+
+enum ocfs2_caching_info_flags {
+	/* Indicates that the metadata cache is using the inline array */
+	OCFS2_CACHE_FL_INLINE	= 1<<1,
+};
 
 struct ocfs2_caching_info {
+	/*
+	 * The parent structure provides the locks, but because the
+	 * parent structure can differ, struct ocfs2_caching_info needs
+	 * its own pointers to them.
+	 */
+	spinlock_t		*ci_lock;
+	struct mutex		*ci_io_mutex;
+
+	unsigned int		ci_flags;
 	unsigned int		ci_num_cached;
 	union {
-		sector_t	ci_array[OCFS2_INODE_MAX_CACHE_ARRAY];
+	sector_t	ci_array[OCFS2_CACHE_INFO_MAX_ARRAY];
 		struct rb_root	ci_tree;
 	} ci_cache;
 };

fs/ocfs2/super.c

@@ -1683,7 +1683,8 @@ static void ocfs2_inode_init_once(void *data)
 	ocfs2_lock_res_init_once(&oi->ip_inode_lockres);
 	ocfs2_lock_res_init_once(&oi->ip_open_lockres);
 
-	ocfs2_metadata_cache_init(&oi->vfs_inode);
+	ocfs2_metadata_cache_init(&oi->ip_metadata_cache, &oi->ip_lock,
+				  &oi->ip_io_mutex);
 
 	inode_init_once(&oi->vfs_inode);
 }

fs/ocfs2/uptodate.h

@@ -29,7 +29,9 @@
 int __init init_ocfs2_uptodate_cache(void);
 void exit_ocfs2_uptodate_cache(void);
 
-void ocfs2_metadata_cache_init(struct inode *inode);
+void ocfs2_metadata_cache_init(struct ocfs2_caching_info *ci,
+			       spinlock_t *cache_lock,
+			       struct mutex *io_mutex);
 void ocfs2_metadata_cache_purge(struct inode *inode);
 
 int ocfs2_buffer_uptodate(struct inode *inode,