1/* -*- mode: c; c-basic-offset: 8; -*-
2 * vim: noexpandtab sw=8 ts=8 sts=0:
3 *
4 * alloc.h
5 *
6 * Function prototypes
7 *
8 * Copyright (C) 2002, 2004 Oracle.  All rights reserved.
9 *
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public
12 * License as published by the Free Software Foundation; either
13 * version 2 of the License, or (at your option) any later version.
14 *
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
18 * General Public License for more details.
19 *
20 * You should have received a copy of the GNU General Public
21 * License along with this program; if not, write to the
22 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
23 * Boston, MA 021110-1307, USA.
24 */
25
26#ifndef OCFS2_ALLOC_H
27#define OCFS2_ALLOC_H
28
29
30/*
31 * For xattr tree leaf, we limit the leaf byte size to be 64K.
32 */
33#define OCFS2_MAX_XATTR_TREE_LEAF_SIZE 65536
34
35/*
36 * ocfs2_extent_tree and ocfs2_extent_tree_operations are used to abstract
37 * the b-tree operations in ocfs2. Now all the b-tree operations are not
38 * limited to ocfs2_dinode only. Any data which need to allocate clusters
39 * to store can use b-tree. And it only needs to implement its ocfs2_extent_tree
40 * and operation.
41 *
42 * ocfs2_extent_tree becomes the first-class object for extent tree
43 * manipulation.  Callers of the alloc.c code need to fill it via one of
44 * the ocfs2_init_*_extent_tree() operations below.
45 *
46 * ocfs2_extent_tree contains info for the root of the b-tree, it must have a
47 * root ocfs2_extent_list and a root_bh so that they can be used in the b-tree
48 * functions.  It needs the ocfs2_caching_info structure associated with
49 * I/O on the tree.  With metadata ecc, we now call different journal_access
50 * functions for each type of metadata, so it must have the
51 * root_journal_access function.
52 * ocfs2_extent_tree_operations abstract the normal operations we do for
53 * the root of extent b-tree.
54 */
55struct ocfs2_extent_tree_operations;
56struct ocfs2_extent_tree {
57	struct ocfs2_extent_tree_operations	*et_ops;
58	struct buffer_head			*et_root_bh;
59	struct ocfs2_extent_list		*et_root_el;
60	struct ocfs2_caching_info		*et_ci;
61	ocfs2_journal_access_func		et_root_journal_access;
62	void					*et_object;
63	unsigned int				et_max_leaf_clusters;
64};
65
66/*
67 * ocfs2_init_*_extent_tree() will fill an ocfs2_extent_tree from the
68 * specified object buffer.
69 */
70void ocfs2_init_dinode_extent_tree(struct ocfs2_extent_tree *et,
71				   struct ocfs2_caching_info *ci,
72				   struct buffer_head *bh);
73void ocfs2_init_xattr_tree_extent_tree(struct ocfs2_extent_tree *et,
74				       struct ocfs2_caching_info *ci,
75				       struct buffer_head *bh);
76struct ocfs2_xattr_value_buf;
77void ocfs2_init_xattr_value_extent_tree(struct ocfs2_extent_tree *et,
78					struct ocfs2_caching_info *ci,
79					struct ocfs2_xattr_value_buf *vb);
80void ocfs2_init_dx_root_extent_tree(struct ocfs2_extent_tree *et,
81				    struct ocfs2_caching_info *ci,
82				    struct buffer_head *bh);
83void ocfs2_init_refcount_extent_tree(struct ocfs2_extent_tree *et,
84				     struct ocfs2_caching_info *ci,
85				     struct buffer_head *bh);
86
87/*
88 * Read an extent block into *bh.  If *bh is NULL, a bh will be
89 * allocated.  This is a cached read.  The extent block will be validated
90 * with ocfs2_validate_extent_block().
91 */
92int ocfs2_read_extent_block(struct ocfs2_caching_info *ci, u64 eb_blkno,
93			    struct buffer_head **bh);
94
95struct ocfs2_alloc_context;
96int ocfs2_insert_extent(handle_t *handle,
97			struct ocfs2_extent_tree *et,
98			u32 cpos,
99			u64 start_blk,
100			u32 new_clusters,
101			u8 flags,
102			struct ocfs2_alloc_context *meta_ac);
103
104enum ocfs2_alloc_restarted {
105	RESTART_NONE = 0,
106	RESTART_TRANS,
107	RESTART_META
108};
109int ocfs2_add_clusters_in_btree(handle_t *handle,
110				struct ocfs2_extent_tree *et,
111				u32 *logical_offset,
112				u32 clusters_to_add,
113				int mark_unwritten,
114				struct ocfs2_alloc_context *data_ac,
115				struct ocfs2_alloc_context *meta_ac,
116				enum ocfs2_alloc_restarted *reason_ret);
117struct ocfs2_cached_dealloc_ctxt;
118struct ocfs2_path;
119int ocfs2_split_extent(handle_t *handle,
120		       struct ocfs2_extent_tree *et,
121		       struct ocfs2_path *path,
122		       int split_index,
123		       struct ocfs2_extent_rec *split_rec,
124		       struct ocfs2_alloc_context *meta_ac,
125		       struct ocfs2_cached_dealloc_ctxt *dealloc);
126int ocfs2_mark_extent_written(struct inode *inode,
127			      struct ocfs2_extent_tree *et,
128			      handle_t *handle, u32 cpos, u32 len, u32 phys,
129			      struct ocfs2_alloc_context *meta_ac,
130			      struct ocfs2_cached_dealloc_ctxt *dealloc);
131int ocfs2_change_extent_flag(handle_t *handle,
132			     struct ocfs2_extent_tree *et,
133			     u32 cpos, u32 len, u32 phys,
134			     struct ocfs2_alloc_context *meta_ac,
135			     struct ocfs2_cached_dealloc_ctxt *dealloc,
136			     int new_flags, int clear_flags);
137int ocfs2_remove_extent(handle_t *handle, struct ocfs2_extent_tree *et,
138			u32 cpos, u32 len,
139			struct ocfs2_alloc_context *meta_ac,
140			struct ocfs2_cached_dealloc_ctxt *dealloc);
141int ocfs2_remove_btree_range(struct inode *inode,
142			     struct ocfs2_extent_tree *et,
143			     u32 cpos, u32 phys_cpos, u32 len, int flags,
144			     struct ocfs2_cached_dealloc_ctxt *dealloc,
145			     u64 refcount_loc);
146
147int ocfs2_num_free_extents(struct ocfs2_super *osb,
148			   struct ocfs2_extent_tree *et);
149
150/*
151 * how many new metadata chunks would an allocation need at maximum?
152 *
153 * Please note that the caller must make sure that root_el is the root
154 * of extent tree. So for an inode, it should be &fe->id2.i_list. Otherwise
155 * the result may be wrong.
156 */
157static inline int ocfs2_extend_meta_needed(struct ocfs2_extent_list *root_el)
158{
159	/*
160	 * Rather than do all the work of determining how much we need
161	 * (involves a ton of reads and locks), just ask for the
162	 * maximal limit.  That's a tree depth shift.  So, one block for
163	 * level of the tree (current l_tree_depth), one block for the
164	 * new tree_depth==0 extent_block, and one block at the new
165	 * top-of-the tree.
166	 */
167	return le16_to_cpu(root_el->l_tree_depth) + 2;
168}
169
170void ocfs2_dinode_new_extent_list(struct inode *inode, struct ocfs2_dinode *di);
171void ocfs2_set_inode_data_inline(struct inode *inode, struct ocfs2_dinode *di);
172int ocfs2_convert_inline_data_to_extents(struct inode *inode,
173					 struct buffer_head *di_bh);
174
175int ocfs2_truncate_log_init(struct ocfs2_super *osb);
176void ocfs2_truncate_log_shutdown(struct ocfs2_super *osb);
177void ocfs2_schedule_truncate_log_flush(struct ocfs2_super *osb,
178				       int cancel);
179int ocfs2_flush_truncate_log(struct ocfs2_super *osb);
180int ocfs2_begin_truncate_log_recovery(struct ocfs2_super *osb,
181				      int slot_num,
182				      struct ocfs2_dinode **tl_copy);
183int ocfs2_complete_truncate_log_recovery(struct ocfs2_super *osb,
184					 struct ocfs2_dinode *tl_copy);
185int ocfs2_truncate_log_needs_flush(struct ocfs2_super *osb);
186int ocfs2_truncate_log_append(struct ocfs2_super *osb,
187			      handle_t *handle,
188			      u64 start_blk,
189			      unsigned int num_clusters);
190int __ocfs2_flush_truncate_log(struct ocfs2_super *osb);
191
192/*
193 * Process local structure which describes the block unlinks done
194 * during an operation. This is populated via
195 * ocfs2_cache_block_dealloc().
196 *
197 * ocfs2_run_deallocs() should be called after the potentially
198 * de-allocating routines. No journal handles should be open, and most
199 * locks should have been dropped.
200 */
201struct ocfs2_cached_dealloc_ctxt {
202	struct ocfs2_per_slot_free_list		*c_first_suballocator;
203	struct ocfs2_cached_block_free 		*c_global_allocator;
204};
205static inline void ocfs2_init_dealloc_ctxt(struct ocfs2_cached_dealloc_ctxt *c)
206{
207	c->c_first_suballocator = NULL;
208	c->c_global_allocator = NULL;
209}
210int ocfs2_cache_cluster_dealloc(struct ocfs2_cached_dealloc_ctxt *ctxt,
211				u64 blkno, unsigned int bit);
212int ocfs2_cache_block_dealloc(struct ocfs2_cached_dealloc_ctxt *ctxt,
213			      int type, int slot, u64 suballoc, u64 blkno,
214			      unsigned int bit);
215static inline int ocfs2_dealloc_has_cluster(struct ocfs2_cached_dealloc_ctxt *c)
216{
217	return c->c_global_allocator != NULL;
218}
219int ocfs2_run_deallocs(struct ocfs2_super *osb,
220		       struct ocfs2_cached_dealloc_ctxt *ctxt);
221
222struct ocfs2_truncate_context {
223	struct ocfs2_cached_dealloc_ctxt tc_dealloc;
224	int tc_ext_alloc_locked; /* is it cluster locked? */
225	/* these get destroyed once it's passed to ocfs2_commit_truncate. */
226	struct buffer_head *tc_last_eb_bh;
227};
228
229int ocfs2_zero_range_for_truncate(struct inode *inode, handle_t *handle,
230				  u64 range_start, u64 range_end);
231int ocfs2_prepare_truncate(struct ocfs2_super *osb,
232			   struct inode *inode,
233			   struct buffer_head *fe_bh,
234			   struct ocfs2_truncate_context **tc);
235int ocfs2_commit_truncate(struct ocfs2_super *osb,
236			  struct inode *inode,
237			  struct buffer_head *di_bh);
238int ocfs2_truncate_inline(struct inode *inode, struct buffer_head *di_bh,
239			  unsigned int start, unsigned int end, int trunc);
240
241int ocfs2_find_leaf(struct ocfs2_caching_info *ci,
242		    struct ocfs2_extent_list *root_el, u32 cpos,
243		    struct buffer_head **leaf_bh);
244int ocfs2_search_extent_list(struct ocfs2_extent_list *el, u32 v_cluster);
245
246/*
247 * Helper function to look at the # of clusters in an extent record.
248 */
249static inline unsigned int ocfs2_rec_clusters(struct ocfs2_extent_list *el,
250					      struct ocfs2_extent_rec *rec)
251{
252	/*
253	 * Cluster count in extent records is slightly different
254	 * between interior nodes and leaf nodes. This is to support
255	 * unwritten extents which need a flags field in leaf node
256	 * records, thus shrinking the available space for a clusters
257	 * field.
258	 */
259	if (el->l_tree_depth)
260		return le32_to_cpu(rec->e_int_clusters);
261	else
262		return le16_to_cpu(rec->e_leaf_clusters);
263}
264
265/*
266 * This is only valid for leaf nodes, which are the only ones that can
267 * have empty extents anyway.
268 */
269static inline int ocfs2_is_empty_extent(struct ocfs2_extent_rec *rec)
270{
271	return !rec->e_leaf_clusters;
272}
273
274int ocfs2_grab_pages(struct inode *inode, loff_t start, loff_t end,
275		     struct page **pages, int *num);
276void ocfs2_map_and_dirty_page(struct inode *inode, handle_t *handle,
277			      unsigned int from, unsigned int to,
278			      struct page *page, int zero, u64 *phys);
279/*
280 * Structures which describe a path through a btree, and functions to
281 * manipulate them.
282 *
283 * The idea here is to be as generic as possible with the tree
284 * manipulation code.
285 */
286struct ocfs2_path_item {
287	struct buffer_head		*bh;
288	struct ocfs2_extent_list	*el;
289};
290
291#define OCFS2_MAX_PATH_DEPTH	5
292
293struct ocfs2_path {
294	int				p_tree_depth;
295	ocfs2_journal_access_func	p_root_access;
296	struct ocfs2_path_item		p_node[OCFS2_MAX_PATH_DEPTH];
297};
298
299#define path_root_bh(_path) ((_path)->p_node[0].bh)
300#define path_root_el(_path) ((_path)->p_node[0].el)
301#define path_root_access(_path)((_path)->p_root_access)
302#define path_leaf_bh(_path) ((_path)->p_node[(_path)->p_tree_depth].bh)
303#define path_leaf_el(_path) ((_path)->p_node[(_path)->p_tree_depth].el)
304#define path_num_items(_path) ((_path)->p_tree_depth + 1)
305
306void ocfs2_reinit_path(struct ocfs2_path *path, int keep_root);
307void ocfs2_free_path(struct ocfs2_path *path);
308int ocfs2_find_path(struct ocfs2_caching_info *ci,
309		    struct ocfs2_path *path,
310		    u32 cpos);
311struct ocfs2_path *ocfs2_new_path_from_path(struct ocfs2_path *path);
312struct ocfs2_path *ocfs2_new_path_from_et(struct ocfs2_extent_tree *et);
313int ocfs2_path_bh_journal_access(handle_t *handle,
314				 struct ocfs2_caching_info *ci,
315				 struct ocfs2_path *path,
316				 int idx);
317int ocfs2_journal_access_path(struct ocfs2_caching_info *ci,
318			      handle_t *handle,
319			      struct ocfs2_path *path);
320int ocfs2_find_cpos_for_right_leaf(struct super_block *sb,
321				   struct ocfs2_path *path, u32 *cpos);
322int ocfs2_find_cpos_for_left_leaf(struct super_block *sb,
323				  struct ocfs2_path *path, u32 *cpos);
324int ocfs2_find_subtree_root(struct ocfs2_extent_tree *et,
325			    struct ocfs2_path *left,
326			    struct ocfs2_path *right);
327#endif /* OCFS2_ALLOC_H */
328