kernel.git/fs/ocfs2/alloc.h, branch linux-2.6.28.y

ocfs2: Change ocfs2_get__extent_tree() to ocfs2_init__extent_tree()

2008-10-13T23:57:05Z

The original get/put_extent_tree() functions held a reference on et_root_bh. However, every single caller already has a safe reference, making the get/put cycle irrelevant. We change ocfs2_get_*_extent_tree() to ocfs2_init_*_extent_tree(). It no longer gets a reference on et_root_bh. ocfs2_put_extent_tree() is removed. Callers now have a simpler init+use pattern. Signed-off-by: Joel Becker Signed-off-by: Mark Fasheh

ocfs2: Make ocfs2_extent_tree the first-class representation of a tree.

2008-10-13T23:57:05Z

We now have three different kinds of extent trees in ocfs2: inode data (dinode), extended attributes (xattr_tree), and extended attribute values (xattr_value). There is a nice abstraction for them, ocfs2_extent_tree, but it is hidden in alloc.c. All the calling functions have to pick amongst a varied API and pass in type bits and often extraneous pointers. A better way is to make ocfs2_extent_tree a first-class object. Everyone converts their object to an ocfs2_extent_tree() via the ocfs2_get_*_extent_tree() calls, then uses the ocfs2_extent_tree for all tree calls to alloc.c. This simplifies a lot of callers, making for readability. It also provides an easy way to add additional extent tree types, as they only need to be defined in alloc.c with a ocfs2_get__extent_tree() function. Signed-off-by: Joel Becker Signed-off-by: Mark Fasheh

ocfs2: Create specific get_extent_tree functions.

2008-10-13T23:57:05Z

A caller knows what kind of extent tree they have. There's no reason they have to call ocfs2_get_extent_tree() with a NULL when they could just as easily call a specific function to their type of extent tree. Introduce ocfs2_dinode_get_extent_tree(), ocfs2_xattr_tree_get_extent_tree(), and ocfs2_xattr_value_get_extent_tree(). They only take the necessary arguments, calling into the underlying __ocfs2_get_extent_tree() to do the real work. __ocfs2_get_extent_tree() is the old ocfs2_get_extent_tree(), but without needing any switch-by-type logic. ocfs2_get_extent_tree() is now a wrapper around the specific calls. It exists because a couple alloc.c functions can take et_type. This will go later. Another benefit is that ocfs2_xattr_value_get_extent_tree() can take a struct ocfs2_xattr_value_root* instead of void*. This gives us typechecking where we didn't have it before. Signed-off-by: Joel Becker Signed-off-by: Mark Fasheh

ocfs2: Optionally limit extent size in ocfs2_insert_extent()

2008-10-13T23:57:03Z

In xattr bucket, we want to limit the maximum size of a btree leaf, otherwise we'll lose the benefits of hashing because we'll have to search large leaves. So add a new field in ocfs2_extent_tree which indicates the maximum leaf cluster size we want so that we can prevent ocfs2_insert_extent() from merging the leaf record even if it is contiguous with an adjacent record. Other btree types are not affected by this change. Signed-off-by: Tao Ma Signed-off-by: Mark Fasheh

ocfs2: Add xattr index tree operations

2008-10-13T23:57:02Z

When necessary, an ocfs2_xattr_block will embed an ocfs2_extent_list to store large numbers of EAs. This patch adds a new type in ocfs2_extent_tree_type and adds the implementation so that we can re-use the b-tree code to handle the storage of many EAs. Signed-off-by: Tao Ma Signed-off-by: Mark Fasheh

ocfs2: Add extent tree operation for xattr value btrees

2008-10-13T23:57:01Z

Add some thin wrappers around ocfs2_insert_extent() for each of the 3 different btree types, ocfs2_inode_insert_extent(), ocfs2_xattr_value_insert_extent() and ocfs2_xattr_tree_insert_extent(). The last is for the xattr index btree, which will be used in a followup patch. All the old callers in file.c etc will call ocfs2_dinode_insert_extent(), while the other two handle the xattr issue. And the init of extent tree are handled by these functions. When storing xattr value which is too large, we will allocate some clusters for it and here ocfs2_extent_list and ocfs2_extent_rec will also be used. In order to re-use the b-tree operation code, a new parameter named "private" is added into ocfs2_extent_tree and it is used to indicate the root of ocfs2_exent_list. The reason is that we can't deduce the root from the buffer_head now. It may be in an inode, an ocfs2_xattr_block or even worse, in any place in an ocfs2_xattr_bucket. Signed-off-by: Tao Ma Signed-off-by: Mark Fasheh

ocfs2: Make high level btree extend code generic

2008-10-13T20:57:59Z

Factor out the non-inode specifics of ocfs2_do_extend_allocation() into a more generic function, ocfs2_do_cluster_allocation(). ocfs2_do_extend_allocation calls ocfs2_do_cluster_allocation() now, but the latter can be used for other btree types as well. Signed-off-by: Tao Ma Signed-off-by: Mark Fasheh

ocfs2: Abstract ocfs2_extent_tree in b-tree operations.

2008-10-13T20:57:58Z

In the old extent tree operation, we take the hypothesis that we are using the ocfs2_extent_list in ocfs2_dinode as the tree root. As xattr will also use ocfs2_extent_list to store large value for a xattr entry, we refactor the tree operation so that xattr can use it directly. The refactoring includes 4 steps: 1. Abstract set/get of last_eb_blk and update_clusters since they may be stored in different location for dinode and xattr. 2. Add a new structure named ocfs2_extent_tree to indicate the extent tree the operation will work on. 3. Remove all the use of fe_bh and di, use root_bh and root_el in extent tree instead. So now all the fe_bh is replaced with et->root_bh, el with root_el accordingly. 4. Make ocfs2_lock_allocators generic. Now it is limited to be only used in file extend allocation. But the whole function is useful when we want to store large EAs. Note: This patch doesn't touch ocfs2_commit_truncate() since it is not used for anything other than truncate inode data btrees. Signed-off-by: Tao Ma Signed-off-by: Mark Fasheh

ocfs2: Use ocfs2_extent_list instead of ocfs2_dinode.

2008-10-13T20:57:58Z

ocfs2_extend_meta_needed(), ocfs2_calc_extend_credits() and ocfs2_reserve_new_metadata() are all useful for extent tree operations. But they are all limited to an inode btree because they use a struct ocfs2_dinode parameter. Change their parameter to struct ocfs2_extent_list (the part of an ocfs2_dinode they actually use) so that the xattr btree code can use these functions. Signed-off-by: Tao Ma Signed-off-by: Mark Fasheh

ocfs2: Modify ocfs2_num_free_extents for future xattr usage.

2008-10-13T20:57:58Z

ocfs2_num_free_extents() is used to find the number of free extent records in an inode btree. Hence, it takes an "ocfs2_dinode" parameter. We want to use this for extended attribute trees in the future, so genericize the interface the take a buffer head. A future patch will allow that buffer_head to contain any structure rooting an ocfs2 btree. Signed-off-by: Tao Ma Signed-off-by: Mark Fasheh

kernel.git/fs/ocfs2/alloc.h, branch linux-2.6.28.y

ocfs2: Change ocfs2_get_*_extent_tree() to ocfs2_init_*_extent_tree()

ocfs2: Make ocfs2_extent_tree the first-class representation of a tree.

ocfs2: Create specific get_extent_tree functions.

ocfs2: Optionally limit extent size in ocfs2_insert_extent()

ocfs2: Add xattr index tree operations

ocfs2: Add extent tree operation for xattr value btrees

ocfs2: Make high level btree extend code generic

ocfs2: Abstract ocfs2_extent_tree in b-tree operations.

ocfs2: Use ocfs2_extent_list instead of ocfs2_dinode.

ocfs2: Modify ocfs2_num_free_extents for future xattr usage.

ocfs2: Change ocfs2_get__extent_tree() to ocfs2_init__extent_tree()