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 */ 55 struct ocfs2_extent_tree_operations; 56 struct 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 */ 70 void ocfs2_init_dinode_extent_tree(struct ocfs2_extent_tree *et, 71 struct ocfs2_caching_info *ci, 72 struct buffer_head *bh); 73 void ocfs2_init_xattr_tree_extent_tree(struct ocfs2_extent_tree *et, 74 struct ocfs2_caching_info *ci, 75 struct buffer_head *bh); 76 struct ocfs2_xattr_value_buf; 77 void ocfs2_init_xattr_value_extent_tree(struct ocfs2_extent_tree *et, 78 struct ocfs2_caching_info *ci, 79 struct ocfs2_xattr_value_buf *vb); 80 void ocfs2_init_dx_root_extent_tree(struct ocfs2_extent_tree *et, 81 struct ocfs2_caching_info *ci, 82 struct buffer_head *bh); 83 void 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 */ 92 int ocfs2_read_extent_block(struct ocfs2_caching_info *ci, u64 eb_blkno, 93 struct buffer_head **bh); 94 95 struct ocfs2_alloc_context; 96 int 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); 103 104 enum ocfs2_alloc_restarted { 105 RESTART_NONE = 0, 106 RESTART_TRANS, 107 RESTART_META 108 }; 109 int 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); 117 struct ocfs2_cached_dealloc_ctxt; 118 struct ocfs2_path; 119 int 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); 126 int 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); 131 int ocfs2_remove_extent(handle_t *handle, struct ocfs2_extent_tree *et, 132 u32 cpos, u32 len, 133 struct ocfs2_alloc_context *meta_ac, 134 struct ocfs2_cached_dealloc_ctxt *dealloc); 135 int ocfs2_remove_btree_range(struct inode *inode, 136 struct ocfs2_extent_tree *et, 137 u32 cpos, u32 phys_cpos, u32 len, 138 struct ocfs2_cached_dealloc_ctxt *dealloc); 139 140 int ocfs2_num_free_extents(struct ocfs2_super *osb, 141 struct ocfs2_extent_tree *et); 142 143 /* 144 * how many new metadata chunks would an allocation need at maximum? 145 * 146 * Please note that the caller must make sure that root_el is the root 147 * of extent tree. So for an inode, it should be &fe->id2.i_list. Otherwise 148 * the result may be wrong. 149 */ 150 static inline int ocfs2_extend_meta_needed(struct ocfs2_extent_list *root_el) 151 { 152 /* 153 * Rather than do all the work of determining how much we need 154 * (involves a ton of reads and locks), just ask for the 155 * maximal limit. That's a tree depth shift. So, one block for 156 * level of the tree (current l_tree_depth), one block for the 157 * new tree_depth==0 extent_block, and one block at the new 158 * top-of-the tree. 159 */ 160 return le16_to_cpu(root_el->l_tree_depth) + 2; 161 } 162 163 void ocfs2_dinode_new_extent_list(struct inode *inode, struct ocfs2_dinode *di); 164 void ocfs2_set_inode_data_inline(struct inode *inode, struct ocfs2_dinode *di); 165 int ocfs2_convert_inline_data_to_extents(struct inode *inode, 166 struct buffer_head *di_bh); 167 168 int ocfs2_truncate_log_init(struct ocfs2_super *osb); 169 void ocfs2_truncate_log_shutdown(struct ocfs2_super *osb); 170 void ocfs2_schedule_truncate_log_flush(struct ocfs2_super *osb, 171 int cancel); 172 int ocfs2_flush_truncate_log(struct ocfs2_super *osb); 173 int ocfs2_begin_truncate_log_recovery(struct ocfs2_super *osb, 174 int slot_num, 175 struct ocfs2_dinode **tl_copy); 176 int ocfs2_complete_truncate_log_recovery(struct ocfs2_super *osb, 177 struct ocfs2_dinode *tl_copy); 178 int ocfs2_truncate_log_needs_flush(struct ocfs2_super *osb); 179 int ocfs2_truncate_log_append(struct ocfs2_super *osb, 180 handle_t *handle, 181 u64 start_blk, 182 unsigned int num_clusters); 183 int __ocfs2_flush_truncate_log(struct ocfs2_super *osb); 184 185 /* 186 * Process local structure which describes the block unlinks done 187 * during an operation. This is populated via 188 * ocfs2_cache_block_dealloc(). 189 * 190 * ocfs2_run_deallocs() should be called after the potentially 191 * de-allocating routines. No journal handles should be open, and most 192 * locks should have been dropped. 193 */ 194 struct ocfs2_cached_dealloc_ctxt { 195 struct ocfs2_per_slot_free_list *c_first_suballocator; 196 struct ocfs2_cached_block_free *c_global_allocator; 197 }; 198 static inline void ocfs2_init_dealloc_ctxt(struct ocfs2_cached_dealloc_ctxt *c) 199 { 200 c->c_first_suballocator = NULL; 201 c->c_global_allocator = NULL; 202 } 203 int ocfs2_cache_cluster_dealloc(struct ocfs2_cached_dealloc_ctxt *ctxt, 204 u64 blkno, unsigned int bit); 205 static inline int ocfs2_dealloc_has_cluster(struct ocfs2_cached_dealloc_ctxt *c) 206 { 207 return c->c_global_allocator != NULL; 208 } 209 int ocfs2_run_deallocs(struct ocfs2_super *osb, 210 struct ocfs2_cached_dealloc_ctxt *ctxt); 211 212 struct ocfs2_truncate_context { 213 struct ocfs2_cached_dealloc_ctxt tc_dealloc; 214 int tc_ext_alloc_locked; /* is it cluster locked? */ 215 /* these get destroyed once it's passed to ocfs2_commit_truncate. */ 216 struct buffer_head *tc_last_eb_bh; 217 }; 218 219 int ocfs2_zero_range_for_truncate(struct inode *inode, handle_t *handle, 220 u64 range_start, u64 range_end); 221 int ocfs2_prepare_truncate(struct ocfs2_super *osb, 222 struct inode *inode, 223 struct buffer_head *fe_bh, 224 struct ocfs2_truncate_context **tc); 225 int ocfs2_commit_truncate(struct ocfs2_super *osb, 226 struct inode *inode, 227 struct buffer_head *fe_bh, 228 struct ocfs2_truncate_context *tc); 229 int ocfs2_truncate_inline(struct inode *inode, struct buffer_head *di_bh, 230 unsigned int start, unsigned int end, int trunc); 231 232 int ocfs2_find_leaf(struct ocfs2_caching_info *ci, 233 struct ocfs2_extent_list *root_el, u32 cpos, 234 struct buffer_head **leaf_bh); 235 int ocfs2_search_extent_list(struct ocfs2_extent_list *el, u32 v_cluster); 236 237 /* 238 * Helper function to look at the # of clusters in an extent record. 239 */ 240 static inline unsigned int ocfs2_rec_clusters(struct ocfs2_extent_list *el, 241 struct ocfs2_extent_rec *rec) 242 { 243 /* 244 * Cluster count in extent records is slightly different 245 * between interior nodes and leaf nodes. This is to support 246 * unwritten extents which need a flags field in leaf node 247 * records, thus shrinking the available space for a clusters 248 * field. 249 */ 250 if (el->l_tree_depth) 251 return le32_to_cpu(rec->e_int_clusters); 252 else 253 return le16_to_cpu(rec->e_leaf_clusters); 254 } 255 256 /* 257 * This is only valid for leaf nodes, which are the only ones that can 258 * have empty extents anyway. 259 */ 260 static inline int ocfs2_is_empty_extent(struct ocfs2_extent_rec *rec) 261 { 262 return !rec->e_leaf_clusters; 263 } 264 265 /* 266 * Structures which describe a path through a btree, and functions to 267 * manipulate them. 268 * 269 * The idea here is to be as generic as possible with the tree 270 * manipulation code. 271 */ 272 struct ocfs2_path_item { 273 struct buffer_head *bh; 274 struct ocfs2_extent_list *el; 275 }; 276 277 #define OCFS2_MAX_PATH_DEPTH 5 278 279 struct ocfs2_path { 280 int p_tree_depth; 281 ocfs2_journal_access_func p_root_access; 282 struct ocfs2_path_item p_node[OCFS2_MAX_PATH_DEPTH]; 283 }; 284 285 #define path_root_bh(_path) ((_path)->p_node[0].bh) 286 #define path_root_el(_path) ((_path)->p_node[0].el) 287 #define path_root_access(_path)((_path)->p_root_access) 288 #define path_leaf_bh(_path) ((_path)->p_node[(_path)->p_tree_depth].bh) 289 #define path_leaf_el(_path) ((_path)->p_node[(_path)->p_tree_depth].el) 290 #define path_num_items(_path) ((_path)->p_tree_depth + 1) 291 292 void ocfs2_reinit_path(struct ocfs2_path *path, int keep_root); 293 void ocfs2_free_path(struct ocfs2_path *path); 294 int ocfs2_find_path(struct ocfs2_caching_info *ci, 295 struct ocfs2_path *path, 296 u32 cpos); 297 struct ocfs2_path *ocfs2_new_path_from_path(struct ocfs2_path *path); 298 struct ocfs2_path *ocfs2_new_path_from_et(struct ocfs2_extent_tree *et); 299 int ocfs2_path_bh_journal_access(handle_t *handle, 300 struct ocfs2_caching_info *ci, 301 struct ocfs2_path *path, 302 int idx); 303 int ocfs2_journal_access_path(struct ocfs2_caching_info *ci, 304 handle_t *handle, 305 struct ocfs2_path *path); 306 #endif /* OCFS2_ALLOC_H */ 307