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 inode *inode, 72 struct buffer_head *bh); 73 void ocfs2_init_xattr_tree_extent_tree(struct ocfs2_extent_tree *et, 74 struct inode *inode, 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 inode *inode, 79 struct ocfs2_xattr_value_buf *vb); 80 void ocfs2_init_dx_root_extent_tree(struct ocfs2_extent_tree *et, 81 struct inode *inode, 82 struct buffer_head *bh); 83 84 /* 85 * Read an extent block into *bh. If *bh is NULL, a bh will be 86 * allocated. This is a cached read. The extent block will be validated 87 * with ocfs2_validate_extent_block(). 88 */ 89 int ocfs2_read_extent_block(struct ocfs2_caching_info *ci, u64 eb_blkno, 90 struct buffer_head **bh); 91 92 struct ocfs2_alloc_context; 93 int ocfs2_insert_extent(handle_t *handle, 94 struct ocfs2_extent_tree *et, 95 u32 cpos, 96 u64 start_blk, 97 u32 new_clusters, 98 u8 flags, 99 struct ocfs2_alloc_context *meta_ac); 100 101 enum ocfs2_alloc_restarted { 102 RESTART_NONE = 0, 103 RESTART_TRANS, 104 RESTART_META 105 }; 106 int ocfs2_add_clusters_in_btree(handle_t *handle, 107 struct ocfs2_extent_tree *et, 108 u32 *logical_offset, 109 u32 clusters_to_add, 110 int mark_unwritten, 111 struct ocfs2_alloc_context *data_ac, 112 struct ocfs2_alloc_context *meta_ac, 113 enum ocfs2_alloc_restarted *reason_ret); 114 struct ocfs2_cached_dealloc_ctxt; 115 int ocfs2_mark_extent_written(struct inode *inode, 116 struct ocfs2_extent_tree *et, 117 handle_t *handle, u32 cpos, u32 len, u32 phys, 118 struct ocfs2_alloc_context *meta_ac, 119 struct ocfs2_cached_dealloc_ctxt *dealloc); 120 int ocfs2_remove_extent(handle_t *handle, struct ocfs2_extent_tree *et, 121 u32 cpos, u32 len, 122 struct ocfs2_alloc_context *meta_ac, 123 struct ocfs2_cached_dealloc_ctxt *dealloc); 124 int ocfs2_remove_btree_range(struct inode *inode, 125 struct ocfs2_extent_tree *et, 126 u32 cpos, u32 phys_cpos, u32 len, 127 struct ocfs2_cached_dealloc_ctxt *dealloc); 128 129 int ocfs2_num_free_extents(struct ocfs2_super *osb, 130 struct ocfs2_extent_tree *et); 131 132 /* 133 * how many new metadata chunks would an allocation need at maximum? 134 * 135 * Please note that the caller must make sure that root_el is the root 136 * of extent tree. So for an inode, it should be &fe->id2.i_list. Otherwise 137 * the result may be wrong. 138 */ 139 static inline int ocfs2_extend_meta_needed(struct ocfs2_extent_list *root_el) 140 { 141 /* 142 * Rather than do all the work of determining how much we need 143 * (involves a ton of reads and locks), just ask for the 144 * maximal limit. That's a tree depth shift. So, one block for 145 * level of the tree (current l_tree_depth), one block for the 146 * new tree_depth==0 extent_block, and one block at the new 147 * top-of-the tree. 148 */ 149 return le16_to_cpu(root_el->l_tree_depth) + 2; 150 } 151 152 void ocfs2_dinode_new_extent_list(struct inode *inode, struct ocfs2_dinode *di); 153 void ocfs2_set_inode_data_inline(struct inode *inode, struct ocfs2_dinode *di); 154 int ocfs2_convert_inline_data_to_extents(struct inode *inode, 155 struct buffer_head *di_bh); 156 157 int ocfs2_truncate_log_init(struct ocfs2_super *osb); 158 void ocfs2_truncate_log_shutdown(struct ocfs2_super *osb); 159 void ocfs2_schedule_truncate_log_flush(struct ocfs2_super *osb, 160 int cancel); 161 int ocfs2_flush_truncate_log(struct ocfs2_super *osb); 162 int ocfs2_begin_truncate_log_recovery(struct ocfs2_super *osb, 163 int slot_num, 164 struct ocfs2_dinode **tl_copy); 165 int ocfs2_complete_truncate_log_recovery(struct ocfs2_super *osb, 166 struct ocfs2_dinode *tl_copy); 167 int ocfs2_truncate_log_needs_flush(struct ocfs2_super *osb); 168 int ocfs2_truncate_log_append(struct ocfs2_super *osb, 169 handle_t *handle, 170 u64 start_blk, 171 unsigned int num_clusters); 172 int __ocfs2_flush_truncate_log(struct ocfs2_super *osb); 173 174 /* 175 * Process local structure which describes the block unlinks done 176 * during an operation. This is populated via 177 * ocfs2_cache_block_dealloc(). 178 * 179 * ocfs2_run_deallocs() should be called after the potentially 180 * de-allocating routines. No journal handles should be open, and most 181 * locks should have been dropped. 182 */ 183 struct ocfs2_cached_dealloc_ctxt { 184 struct ocfs2_per_slot_free_list *c_first_suballocator; 185 struct ocfs2_cached_block_free *c_global_allocator; 186 }; 187 static inline void ocfs2_init_dealloc_ctxt(struct ocfs2_cached_dealloc_ctxt *c) 188 { 189 c->c_first_suballocator = NULL; 190 c->c_global_allocator = NULL; 191 } 192 int ocfs2_cache_cluster_dealloc(struct ocfs2_cached_dealloc_ctxt *ctxt, 193 u64 blkno, unsigned int bit); 194 static inline int ocfs2_dealloc_has_cluster(struct ocfs2_cached_dealloc_ctxt *c) 195 { 196 return c->c_global_allocator != NULL; 197 } 198 int ocfs2_run_deallocs(struct ocfs2_super *osb, 199 struct ocfs2_cached_dealloc_ctxt *ctxt); 200 201 struct ocfs2_truncate_context { 202 struct ocfs2_cached_dealloc_ctxt tc_dealloc; 203 int tc_ext_alloc_locked; /* is it cluster locked? */ 204 /* these get destroyed once it's passed to ocfs2_commit_truncate. */ 205 struct buffer_head *tc_last_eb_bh; 206 }; 207 208 int ocfs2_zero_range_for_truncate(struct inode *inode, handle_t *handle, 209 u64 range_start, u64 range_end); 210 int ocfs2_prepare_truncate(struct ocfs2_super *osb, 211 struct inode *inode, 212 struct buffer_head *fe_bh, 213 struct ocfs2_truncate_context **tc); 214 int ocfs2_commit_truncate(struct ocfs2_super *osb, 215 struct inode *inode, 216 struct buffer_head *fe_bh, 217 struct ocfs2_truncate_context *tc); 218 int ocfs2_truncate_inline(struct inode *inode, struct buffer_head *di_bh, 219 unsigned int start, unsigned int end, int trunc); 220 221 int ocfs2_find_leaf(struct ocfs2_caching_info *ci, 222 struct ocfs2_extent_list *root_el, u32 cpos, 223 struct buffer_head **leaf_bh); 224 int ocfs2_search_extent_list(struct ocfs2_extent_list *el, u32 v_cluster); 225 226 /* 227 * Helper function to look at the # of clusters in an extent record. 228 */ 229 static inline unsigned int ocfs2_rec_clusters(struct ocfs2_extent_list *el, 230 struct ocfs2_extent_rec *rec) 231 { 232 /* 233 * Cluster count in extent records is slightly different 234 * between interior nodes and leaf nodes. This is to support 235 * unwritten extents which need a flags field in leaf node 236 * records, thus shrinking the available space for a clusters 237 * field. 238 */ 239 if (el->l_tree_depth) 240 return le32_to_cpu(rec->e_int_clusters); 241 else 242 return le16_to_cpu(rec->e_leaf_clusters); 243 } 244 245 /* 246 * This is only valid for leaf nodes, which are the only ones that can 247 * have empty extents anyway. 248 */ 249 static inline int ocfs2_is_empty_extent(struct ocfs2_extent_rec *rec) 250 { 251 return !rec->e_leaf_clusters; 252 } 253 254 #endif /* OCFS2_ALLOC_H */ 255