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. 49 * ocfs2_extent_tree_operations abstract the normal operations we do for 50 * the root of extent b-tree. 51 */ 52 struct ocfs2_extent_tree_operations; 53 struct ocfs2_extent_tree { 54 struct ocfs2_extent_tree_operations *et_ops; 55 struct buffer_head *et_root_bh; 56 struct ocfs2_extent_list *et_root_el; 57 void *et_object; 58 unsigned int et_max_leaf_clusters; 59 }; 60 61 /* 62 * ocfs2_init_*_extent_tree() will fill an ocfs2_extent_tree from the 63 * specified object buffer. 64 */ 65 void ocfs2_init_dinode_extent_tree(struct ocfs2_extent_tree *et, 66 struct inode *inode, 67 struct buffer_head *bh); 68 void ocfs2_init_xattr_tree_extent_tree(struct ocfs2_extent_tree *et, 69 struct inode *inode, 70 struct buffer_head *bh); 71 void ocfs2_init_xattr_value_extent_tree(struct ocfs2_extent_tree *et, 72 struct inode *inode, 73 struct buffer_head *bh, 74 struct ocfs2_xattr_value_root *xv); 75 76 struct ocfs2_alloc_context; 77 int ocfs2_insert_extent(struct ocfs2_super *osb, 78 handle_t *handle, 79 struct inode *inode, 80 struct ocfs2_extent_tree *et, 81 u32 cpos, 82 u64 start_blk, 83 u32 new_clusters, 84 u8 flags, 85 struct ocfs2_alloc_context *meta_ac); 86 87 enum ocfs2_alloc_restarted { 88 RESTART_NONE = 0, 89 RESTART_TRANS, 90 RESTART_META 91 }; 92 int ocfs2_add_clusters_in_btree(struct ocfs2_super *osb, 93 struct inode *inode, 94 u32 *logical_offset, 95 u32 clusters_to_add, 96 int mark_unwritten, 97 struct ocfs2_extent_tree *et, 98 handle_t *handle, 99 struct ocfs2_alloc_context *data_ac, 100 struct ocfs2_alloc_context *meta_ac, 101 enum ocfs2_alloc_restarted *reason_ret); 102 struct ocfs2_cached_dealloc_ctxt; 103 int ocfs2_mark_extent_written(struct inode *inode, 104 struct ocfs2_extent_tree *et, 105 handle_t *handle, u32 cpos, u32 len, u32 phys, 106 struct ocfs2_alloc_context *meta_ac, 107 struct ocfs2_cached_dealloc_ctxt *dealloc); 108 int ocfs2_remove_extent(struct inode *inode, 109 struct ocfs2_extent_tree *et, 110 u32 cpos, u32 len, handle_t *handle, 111 struct ocfs2_alloc_context *meta_ac, 112 struct ocfs2_cached_dealloc_ctxt *dealloc); 113 int ocfs2_remove_btree_range(struct inode *inode, 114 struct ocfs2_extent_tree *et, 115 u32 cpos, u32 phys_cpos, u32 len, 116 struct ocfs2_cached_dealloc_ctxt *dealloc); 117 118 int ocfs2_num_free_extents(struct ocfs2_super *osb, 119 struct inode *inode, 120 struct ocfs2_extent_tree *et); 121 122 /* 123 * how many new metadata chunks would an allocation need at maximum? 124 * 125 * Please note that the caller must make sure that root_el is the root 126 * of extent tree. So for an inode, it should be &fe->id2.i_list. Otherwise 127 * the result may be wrong. 128 */ 129 static inline int ocfs2_extend_meta_needed(struct ocfs2_extent_list *root_el) 130 { 131 /* 132 * Rather than do all the work of determining how much we need 133 * (involves a ton of reads and locks), just ask for the 134 * maximal limit. That's a tree depth shift. So, one block for 135 * level of the tree (current l_tree_depth), one block for the 136 * new tree_depth==0 extent_block, and one block at the new 137 * top-of-the tree. 138 */ 139 return le16_to_cpu(root_el->l_tree_depth) + 2; 140 } 141 142 void ocfs2_dinode_new_extent_list(struct inode *inode, struct ocfs2_dinode *di); 143 void ocfs2_set_inode_data_inline(struct inode *inode, struct ocfs2_dinode *di); 144 int ocfs2_convert_inline_data_to_extents(struct inode *inode, 145 struct buffer_head *di_bh); 146 147 int ocfs2_truncate_log_init(struct ocfs2_super *osb); 148 void ocfs2_truncate_log_shutdown(struct ocfs2_super *osb); 149 void ocfs2_schedule_truncate_log_flush(struct ocfs2_super *osb, 150 int cancel); 151 int ocfs2_flush_truncate_log(struct ocfs2_super *osb); 152 int ocfs2_begin_truncate_log_recovery(struct ocfs2_super *osb, 153 int slot_num, 154 struct ocfs2_dinode **tl_copy); 155 int ocfs2_complete_truncate_log_recovery(struct ocfs2_super *osb, 156 struct ocfs2_dinode *tl_copy); 157 int ocfs2_truncate_log_needs_flush(struct ocfs2_super *osb); 158 int ocfs2_truncate_log_append(struct ocfs2_super *osb, 159 handle_t *handle, 160 u64 start_blk, 161 unsigned int num_clusters); 162 int __ocfs2_flush_truncate_log(struct ocfs2_super *osb); 163 164 /* 165 * Process local structure which describes the block unlinks done 166 * during an operation. This is populated via 167 * ocfs2_cache_block_dealloc(). 168 * 169 * ocfs2_run_deallocs() should be called after the potentially 170 * de-allocating routines. No journal handles should be open, and most 171 * locks should have been dropped. 172 */ 173 struct ocfs2_cached_dealloc_ctxt { 174 struct ocfs2_per_slot_free_list *c_first_suballocator; 175 struct ocfs2_cached_block_free *c_global_allocator; 176 }; 177 static inline void ocfs2_init_dealloc_ctxt(struct ocfs2_cached_dealloc_ctxt *c) 178 { 179 c->c_first_suballocator = NULL; 180 c->c_global_allocator = NULL; 181 } 182 int ocfs2_cache_cluster_dealloc(struct ocfs2_cached_dealloc_ctxt *ctxt, 183 u64 blkno, unsigned int bit); 184 static inline int ocfs2_dealloc_has_cluster(struct ocfs2_cached_dealloc_ctxt *c) 185 { 186 return c->c_global_allocator != NULL; 187 } 188 int ocfs2_run_deallocs(struct ocfs2_super *osb, 189 struct ocfs2_cached_dealloc_ctxt *ctxt); 190 191 struct ocfs2_truncate_context { 192 struct ocfs2_cached_dealloc_ctxt tc_dealloc; 193 int tc_ext_alloc_locked; /* is it cluster locked? */ 194 /* these get destroyed once it's passed to ocfs2_commit_truncate. */ 195 struct buffer_head *tc_last_eb_bh; 196 }; 197 198 int ocfs2_zero_range_for_truncate(struct inode *inode, handle_t *handle, 199 u64 range_start, u64 range_end); 200 int ocfs2_prepare_truncate(struct ocfs2_super *osb, 201 struct inode *inode, 202 struct buffer_head *fe_bh, 203 struct ocfs2_truncate_context **tc); 204 int ocfs2_commit_truncate(struct ocfs2_super *osb, 205 struct inode *inode, 206 struct buffer_head *fe_bh, 207 struct ocfs2_truncate_context *tc); 208 int ocfs2_truncate_inline(struct inode *inode, struct buffer_head *di_bh, 209 unsigned int start, unsigned int end, int trunc); 210 211 int ocfs2_find_leaf(struct inode *inode, struct ocfs2_extent_list *root_el, 212 u32 cpos, struct buffer_head **leaf_bh); 213 int ocfs2_search_extent_list(struct ocfs2_extent_list *el, u32 v_cluster); 214 215 /* 216 * Helper function to look at the # of clusters in an extent record. 217 */ 218 static inline unsigned int ocfs2_rec_clusters(struct ocfs2_extent_list *el, 219 struct ocfs2_extent_rec *rec) 220 { 221 /* 222 * Cluster count in extent records is slightly different 223 * between interior nodes and leaf nodes. This is to support 224 * unwritten extents which need a flags field in leaf node 225 * records, thus shrinking the available space for a clusters 226 * field. 227 */ 228 if (el->l_tree_depth) 229 return le32_to_cpu(rec->e_int_clusters); 230 else 231 return le16_to_cpu(rec->e_leaf_clusters); 232 } 233 234 /* 235 * This is only valid for leaf nodes, which are the only ones that can 236 * have empty extents anyway. 237 */ 238 static inline int ocfs2_is_empty_extent(struct ocfs2_extent_rec *rec) 239 { 240 return !rec->e_leaf_clusters; 241 } 242 243 #endif /* OCFS2_ALLOC_H */ 244