- 根目录:
- fs
- ocfs2
- alloc.h
/* -*- 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
/*
* For xattr tree leaf, we limit the leaf byte size to be 64K.
*/
#define OCFS2_MAX_XATTR_TREE_LEAF_SIZE 65536
/*
* ocfs2_extent_tree and ocfs2_extent_tree_operations are used to abstract
* the b-tree operations in ocfs2. Now all the b-tree operations are not
* limited to ocfs2_dinode only. Any data which need to allocate clusters
* to store can use b-tree. And it only needs to implement its ocfs2_extent_tree
* and operation.
*
* ocfs2_extent_tree becomes the first-class object for extent tree
* manipulation. Callers of the alloc.c code need to fill it via one of
* the ocfs2_init_*_extent_tree() operations below.
*
* ocfs2_extent_tree contains info for the root of the b-tree, it must have a
* root ocfs2_extent_list and a root_bh so that they can be used in the b-tree
* functions. It needs the ocfs2_caching_info structure associated with
* I/O on the tree. With metadata ecc, we now call different journal_access
* functions for each type of metadata, so it must have the
* root_journal_access function.
* ocfs2_extent_tree_operations abstract the normal operations we do for
* the root of extent b-tree.
*/
struct ocfs2_extent_tree_operations;
struct ocfs2_extent_tree {
struct ocfs2_extent_tree_operations *et_ops;
struct buffer_head *et_root_bh;
struct ocfs2_extent_list *et_root_el;
struct ocfs2_caching_info *et_ci;
ocfs2_journal_access_func et_root_journal_access;
void *et_object;
unsigned int et_max_leaf_clusters;
};
/*
* ocfs2_init_*_extent_tree() will fill an ocfs2_extent_tree from the
* specified object buffer.
*/
void ocfs2_init_dinode_extent_tree(struct ocfs2_extent_tree *et,
struct ocfs2_caching_info *ci,
struct buffer_head *bh);
void ocfs2_init_xattr_tree_extent_tree(struct ocfs2_extent_tree *et,
struct ocfs2_caching_info *ci,
struct buffer_head *bh);
struct ocfs2_xattr_value_buf;
void ocfs2_init_xattr_value_extent_tree(struct ocfs2_extent_tree *et,
struct ocfs2_caching_info *ci,
struct ocfs2_xattr_value_buf *vb);
void ocfs2_init_dx_root_extent_tree(struct ocfs2_extent_tree *et,
struct ocfs2_caching_info *ci,
struct buffer_head *bh);
void ocfs2_init_refcount_extent_tree(struct ocfs2_extent_tree *et,
struct ocfs2_caching_info *ci,
struct buffer_head *bh);
/*
* Read an extent block into *bh. If *bh is NULL, a bh will be
* allocated. This is a cached read. The extent block will be validated
* with ocfs2_validate_extent_block().
*/
int ocfs2_read_extent_block(struct ocfs2_caching_info *ci, u64 eb_blkno,
struct buffer_head **bh);
struct ocfs2_alloc_context;
int ocfs2_insert_extent(handle_t *handle,
struct ocfs2_extent_tree *et,
u32 cpos,
u64 start_blk,
u32 new_clusters,
u8 flags,
struct ocfs2_alloc_context *meta_ac);
enum ocfs2_alloc_restarted {
RESTART_NONE = 0,
RESTART_TRANS,
RESTART_META
};
int ocfs2_add_clusters_in_btree(handle_t *handle,
struct ocfs2_extent_tree *et,
u32 *logical_offset,
u32 clusters_to_add,
int mark_unwritten,
struct ocfs2_alloc_context *data_ac,
struct ocfs2_alloc_context *meta_ac,
enum ocfs2_alloc_restarted *reason_ret);
struct ocfs2_cached_dealloc_ctxt;
struct ocfs2_path;
int ocfs2_split_extent(handle_t *handle,
struct ocfs2_extent_tree *et,
struct ocfs2_path *path,
int split_index,
struct ocfs2_extent_rec *split_rec,
struct ocfs2_alloc_context *meta_ac,
struct ocfs2_cached_dealloc_ctxt *dealloc);
int ocfs2_mark_extent_written(struct inode *inode,
struct ocfs2_extent_tree *et,
handle_t *handle, u32 cpos, u32 len, u32 phys,
struct ocfs2_alloc_context *meta_ac,
struct ocfs2_cached_dealloc_ctxt *dealloc);
int ocfs2_change_extent_flag(handle_t *handle,
struct ocfs2_extent_tree *et,
u32 cpos, u32 len, u32 phys,
struct ocfs2_alloc_context *meta_ac,
struct ocfs2_cached_dealloc_ctxt *dealloc,
int new_flags, int clear_flags);
int ocfs2_remove_extent(handle_t *handle, struct ocfs2_extent_tree *et,
u32 cpos, u32 len,
struct ocfs2_alloc_context *meta_ac,
struct ocfs2_cached_dealloc_ctxt *dealloc);
int ocfs2_remove_btree_range(struct inode *inode,
struct ocfs2_extent_tree *et,
u32 cpos, u32 phys_cpos, u32 len, int flags,
struct ocfs2_cached_dealloc_ctxt *dealloc,
u64 refcount_loc);
int ocfs2_num_free_extents(struct ocfs2_super *osb,
struct ocfs2_extent_tree *et);
/*
* 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;
struct ocfs2_cached_block_free *c_global_allocator;
};
static inline void ocfs2_init_dealloc_ctxt(struct ocfs2_cached_dealloc_ctxt *c)
{
c->c_first_suballocator = NULL;
c->c_global_allocator = NULL;
}
int ocfs2_cache_cluster_dealloc(struct ocfs2_cached_dealloc_ctxt *ctxt,
u64 blkno, unsigned int bit);
int ocfs2_cache_block_dealloc(struct ocfs2_cached_dealloc_ctxt *ctxt,
int type, int slot, u64 suballoc, u64 blkno,
unsigned int bit);
static inline int ocfs2_dealloc_has_cluster(struct ocfs2_cached_dealloc_ctxt *c)
{
return c->c_global_allocator != 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_commit_truncate(struct ocfs2_super *osb,
struct inode *inode,
struct buffer_head *di_bh);
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 ocfs2_caching_info *ci,
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);
int ocfs2_trim_fs(struct super_block *sb, struct fstrim_range *range);
/*
* 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;
}
int ocfs2_grab_pages(struct inode *inode, loff_t start, loff_t end,
struct page **pages, int *num);
void ocfs2_map_and_dirty_page(struct inode *inode, handle_t *handle,
unsigned int from, unsigned int to,
struct page *page, int zero, u64 *phys);
/*
* Structures which describe a path through a btree, and functions to
* manipulate them.
*
* The idea here is to be as generic as possible with the tree
* manipulation code.
*/
struct ocfs2_path_item {
struct buffer_head *bh;
struct ocfs2_extent_list *el;
};
#define OCFS2_MAX_PATH_DEPTH 5
struct ocfs2_path {
int p_tree_depth;
ocfs2_journal_access_func p_root_access;
struct ocfs2_path_item p_node[OCFS2_MAX_PATH_DEPTH];
};
#define path_root_bh(_path) ((_path)->p_node[0].bh)
#define path_root_el(_path) ((_path)->p_node[0].el)
#define path_root_access(_path)((_path)->p_root_access)
#define path_leaf_bh(_path) ((_path)->p_node[(_path)->p_tree_depth].bh)
#define path_leaf_el(_path) ((_path)->p_node[(_path)->p_tree_depth].el)
#define path_num_items(_path) ((_path)->p_tree_depth + 1)
void ocfs2_reinit_path(struct ocfs2_path *path, int keep_root);
void ocfs2_free_path(struct ocfs2_path *path);
int ocfs2_find_path(struct ocfs2_caching_info *ci,
struct ocfs2_path *path,
u32 cpos);
struct ocfs2_path *ocfs2_new_path_from_path(struct ocfs2_path *path);
struct ocfs2_path *ocfs2_new_path_from_et(struct ocfs2_extent_tree *et);
int ocfs2_path_bh_journal_access(handle_t *handle,
struct ocfs2_caching_info *ci,
struct ocfs2_path *path,
int idx);
int ocfs2_journal_access_path(struct ocfs2_caching_info *ci,
handle_t *handle,
struct ocfs2_path *path);
int ocfs2_find_cpos_for_right_leaf(struct super_block *sb,
struct ocfs2_path *path, u32 *cpos);
int ocfs2_find_cpos_for_left_leaf(struct super_block *sb,
struct ocfs2_path *path, u32 *cpos);
int ocfs2_find_subtree_root(struct ocfs2_extent_tree *et,
struct ocfs2_path *left,
struct ocfs2_path *right);
#endif /* OCFS2_ALLOC_H */