linux/fs/ocfs2/alloc.h
Tao Ma e7d4cb6bc1 ocfs2: Abstract ocfs2_extent_tree in b-tree operations.
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 <tao.ma@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2008-10-13 13:57:58 -07:00

174 lines
6.1 KiB
C

/* -*- mode: c; c-basic-offset: 8; -*-
* vim: noexpandtab sw=8 ts=8 sts=0:
*
* alloc.h
*
* Function prototypes
*
* Copyright (C) 2002, 2004 Oracle. All rights reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public
* License along with this program; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 021110-1307, USA.
*/
#ifndef OCFS2_ALLOC_H
#define OCFS2_ALLOC_H
enum ocfs2_extent_tree_type {
OCFS2_DINODE_EXTENT = 0,
};
struct ocfs2_alloc_context;
int ocfs2_insert_extent(struct ocfs2_super *osb,
handle_t *handle,
struct inode *inode,
struct buffer_head *root_bh,
u32 cpos,
u64 start_blk,
u32 new_clusters,
u8 flags,
struct ocfs2_alloc_context *meta_ac,
enum ocfs2_extent_tree_type et_type);
struct ocfs2_cached_dealloc_ctxt;
int ocfs2_mark_extent_written(struct inode *inode, struct buffer_head *root_bh,
handle_t *handle, u32 cpos, u32 len, u32 phys,
struct ocfs2_alloc_context *meta_ac,
struct ocfs2_cached_dealloc_ctxt *dealloc,
enum ocfs2_extent_tree_type et_type);
int ocfs2_remove_extent(struct inode *inode, struct buffer_head *root_bh,
u32 cpos, u32 len, handle_t *handle,
struct ocfs2_alloc_context *meta_ac,
struct ocfs2_cached_dealloc_ctxt *dealloc,
enum ocfs2_extent_tree_type et_type);
int ocfs2_num_free_extents(struct ocfs2_super *osb,
struct inode *inode,
struct buffer_head *root_bh,
enum ocfs2_extent_tree_type et_type);
/*
* how many new metadata chunks would an allocation need at maximum?
*
* Please note that the caller must make sure that root_el is the root
* of extent tree. So for an inode, it should be &fe->id2.i_list. Otherwise
* the result may be wrong.
*/
static inline int ocfs2_extend_meta_needed(struct ocfs2_extent_list *root_el)
{
/*
* Rather than do all the work of determining how much we need
* (involves a ton of reads and locks), just ask for the
* maximal limit. That's a tree depth shift. So, one block for
* level of the tree (current l_tree_depth), one block for the
* new tree_depth==0 extent_block, and one block at the new
* top-of-the tree.
*/
return le16_to_cpu(root_el->l_tree_depth) + 2;
}
void ocfs2_dinode_new_extent_list(struct inode *inode, struct ocfs2_dinode *di);
void ocfs2_set_inode_data_inline(struct inode *inode, struct ocfs2_dinode *di);
int ocfs2_convert_inline_data_to_extents(struct inode *inode,
struct buffer_head *di_bh);
int ocfs2_truncate_log_init(struct ocfs2_super *osb);
void ocfs2_truncate_log_shutdown(struct ocfs2_super *osb);
void ocfs2_schedule_truncate_log_flush(struct ocfs2_super *osb,
int cancel);
int ocfs2_flush_truncate_log(struct ocfs2_super *osb);
int ocfs2_begin_truncate_log_recovery(struct ocfs2_super *osb,
int slot_num,
struct ocfs2_dinode **tl_copy);
int ocfs2_complete_truncate_log_recovery(struct ocfs2_super *osb,
struct ocfs2_dinode *tl_copy);
int ocfs2_truncate_log_needs_flush(struct ocfs2_super *osb);
int ocfs2_truncate_log_append(struct ocfs2_super *osb,
handle_t *handle,
u64 start_blk,
unsigned int num_clusters);
int __ocfs2_flush_truncate_log(struct ocfs2_super *osb);
/*
* Process local structure which describes the block unlinks done
* during an operation. This is populated via
* ocfs2_cache_block_dealloc().
*
* ocfs2_run_deallocs() should be called after the potentially
* de-allocating routines. No journal handles should be open, and most
* locks should have been dropped.
*/
struct ocfs2_cached_dealloc_ctxt {
struct ocfs2_per_slot_free_list *c_first_suballocator;
};
static inline void ocfs2_init_dealloc_ctxt(struct ocfs2_cached_dealloc_ctxt *c)
{
c->c_first_suballocator = NULL;
}
int ocfs2_run_deallocs(struct ocfs2_super *osb,
struct ocfs2_cached_dealloc_ctxt *ctxt);
struct ocfs2_truncate_context {
struct ocfs2_cached_dealloc_ctxt tc_dealloc;
int tc_ext_alloc_locked; /* is it cluster locked? */
/* these get destroyed once it's passed to ocfs2_commit_truncate. */
struct buffer_head *tc_last_eb_bh;
};
int ocfs2_zero_range_for_truncate(struct inode *inode, handle_t *handle,
u64 range_start, u64 range_end);
int ocfs2_prepare_truncate(struct ocfs2_super *osb,
struct inode *inode,
struct buffer_head *fe_bh,
struct ocfs2_truncate_context **tc);
int ocfs2_commit_truncate(struct ocfs2_super *osb,
struct inode *inode,
struct buffer_head *fe_bh,
struct ocfs2_truncate_context *tc);
int ocfs2_truncate_inline(struct inode *inode, struct buffer_head *di_bh,
unsigned int start, unsigned int end, int trunc);
int ocfs2_find_leaf(struct inode *inode, struct ocfs2_extent_list *root_el,
u32 cpos, struct buffer_head **leaf_bh);
int ocfs2_search_extent_list(struct ocfs2_extent_list *el, u32 v_cluster);
/*
* Helper function to look at the # of clusters in an extent record.
*/
static inline unsigned int ocfs2_rec_clusters(struct ocfs2_extent_list *el,
struct ocfs2_extent_rec *rec)
{
/*
* Cluster count in extent records is slightly different
* between interior nodes and leaf nodes. This is to support
* unwritten extents which need a flags field in leaf node
* records, thus shrinking the available space for a clusters
* field.
*/
if (el->l_tree_depth)
return le32_to_cpu(rec->e_int_clusters);
else
return le16_to_cpu(rec->e_leaf_clusters);
}
/*
* This is only valid for leaf nodes, which are the only ones that can
* have empty extents anyway.
*/
static inline int ocfs2_is_empty_extent(struct ocfs2_extent_rec *rec)
{
return !rec->e_leaf_clusters;
}
#endif /* OCFS2_ALLOC_H */