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 /* 77 * Read an extent block into *bh. If *bh is NULL, a bh will be 78 * allocated. This is a cached read. The extent block will be validated 79 * with ocfs2_validate_extent_block(). 80 */ 81 int ocfs2_read_extent_block(struct inode *inode, u64 eb_blkno, 82 struct buffer_head **bh); 83 84 struct ocfs2_alloc_context; 85 int ocfs2_insert_extent(struct ocfs2_super *osb, 86 handle_t *handle, 87 struct inode *inode, 88 struct ocfs2_extent_tree *et, 89 u32 cpos, 90 u64 start_blk, 91 u32 new_clusters, 92 u8 flags, 93 struct ocfs2_alloc_context *meta_ac); 94 95 enum ocfs2_alloc_restarted { 96 RESTART_NONE = 0, 97 RESTART_TRANS, 98 RESTART_META 99 }; 100 int ocfs2_add_clusters_in_btree(struct ocfs2_super *osb, 101 struct inode *inode, 102 u32 *logical_offset, 103 u32 clusters_to_add, 104 int mark_unwritten, 105 struct ocfs2_extent_tree *et, 106 handle_t *handle, 107 struct ocfs2_alloc_context *data_ac, 108 struct ocfs2_alloc_context *meta_ac, 109 enum ocfs2_alloc_restarted *reason_ret); 110 struct ocfs2_cached_dealloc_ctxt; 111 int ocfs2_mark_extent_written(struct inode *inode, 112 struct ocfs2_extent_tree *et, 113 handle_t *handle, u32 cpos, u32 len, u32 phys, 114 struct ocfs2_alloc_context *meta_ac, 115 struct ocfs2_cached_dealloc_ctxt *dealloc); 116 int ocfs2_remove_extent(struct inode *inode, 117 struct ocfs2_extent_tree *et, 118 u32 cpos, u32 len, handle_t *handle, 119 struct ocfs2_alloc_context *meta_ac, 120 struct ocfs2_cached_dealloc_ctxt *dealloc); 121 int ocfs2_remove_btree_range(struct inode *inode, 122 struct ocfs2_extent_tree *et, 123 u32 cpos, u32 phys_cpos, u32 len, 124 struct ocfs2_cached_dealloc_ctxt *dealloc); 125 126 int ocfs2_num_free_extents(struct ocfs2_super *osb, 127 struct inode *inode, 128 struct ocfs2_extent_tree *et); 129 130 /* 131 * how many new metadata chunks would an allocation need at maximum? 132 * 133 * Please note that the caller must make sure that root_el is the root 134 * of extent tree. So for an inode, it should be &fe->id2.i_list. Otherwise 135 * the result may be wrong. 136 */ 137 static inline int ocfs2_extend_meta_needed(struct ocfs2_extent_list *root_el) 138 { 139 /* 140 * Rather than do all the work of determining how much we need 141 * (involves a ton of reads and locks), just ask for the 142 * maximal limit. That's a tree depth shift. So, one block for 143 * level of the tree (current l_tree_depth), one block for the 144 * new tree_depth==0 extent_block, and one block at the new 145 * top-of-the tree. 146 */ 147 return le16_to_cpu(root_el->l_tree_depth) + 2; 148 } 149 150 void ocfs2_dinode_new_extent_list(struct inode *inode, struct ocfs2_dinode *di); 151 void ocfs2_set_inode_data_inline(struct inode *inode, struct ocfs2_dinode *di); 152 int ocfs2_convert_inline_data_to_extents(struct inode *inode, 153 struct buffer_head *di_bh); 154 155 int ocfs2_truncate_log_init(struct ocfs2_super *osb); 156 void ocfs2_truncate_log_shutdown(struct ocfs2_super *osb); 157 void ocfs2_schedule_truncate_log_flush(struct ocfs2_super *osb, 158 int cancel); 159 int ocfs2_flush_truncate_log(struct ocfs2_super *osb); 160 int ocfs2_begin_truncate_log_recovery(struct ocfs2_super *osb, 161 int slot_num, 162 struct ocfs2_dinode **tl_copy); 163 int ocfs2_complete_truncate_log_recovery(struct ocfs2_super *osb, 164 struct ocfs2_dinode *tl_copy); 165 int ocfs2_truncate_log_needs_flush(struct ocfs2_super *osb); 166 int ocfs2_truncate_log_append(struct ocfs2_super *osb, 167 handle_t *handle, 168 u64 start_blk, 169 unsigned int num_clusters); 170 int __ocfs2_flush_truncate_log(struct ocfs2_super *osb); 171 172 /* 173 * Process local structure which describes the block unlinks done 174 * during an operation. This is populated via 175 * ocfs2_cache_block_dealloc(). 176 * 177 * ocfs2_run_deallocs() should be called after the potentially 178 * de-allocating routines. No journal handles should be open, and most 179 * locks should have been dropped. 180 */ 181 struct ocfs2_cached_dealloc_ctxt { 182 struct ocfs2_per_slot_free_list *c_first_suballocator; 183 struct ocfs2_cached_block_free *c_global_allocator; 184 }; 185 static inline void ocfs2_init_dealloc_ctxt(struct ocfs2_cached_dealloc_ctxt *c) 186 { 187 c->c_first_suballocator = NULL; 188 c->c_global_allocator = NULL; 189 } 190 int ocfs2_cache_cluster_dealloc(struct ocfs2_cached_dealloc_ctxt *ctxt, 191 u64 blkno, unsigned int bit); 192 static inline int ocfs2_dealloc_has_cluster(struct ocfs2_cached_dealloc_ctxt *c) 193 { 194 return c->c_global_allocator != NULL; 195 } 196 int ocfs2_run_deallocs(struct ocfs2_super *osb, 197 struct ocfs2_cached_dealloc_ctxt *ctxt); 198 199 struct ocfs2_truncate_context { 200 struct ocfs2_cached_dealloc_ctxt tc_dealloc; 201 int tc_ext_alloc_locked; /* is it cluster locked? */ 202 /* these get destroyed once it's passed to ocfs2_commit_truncate. */ 203 struct buffer_head *tc_last_eb_bh; 204 }; 205 206 int ocfs2_zero_range_for_truncate(struct inode *inode, handle_t *handle, 207 u64 range_start, u64 range_end); 208 int ocfs2_prepare_truncate(struct ocfs2_super *osb, 209 struct inode *inode, 210 struct buffer_head *fe_bh, 211 struct ocfs2_truncate_context **tc); 212 int ocfs2_commit_truncate(struct ocfs2_super *osb, 213 struct inode *inode, 214 struct buffer_head *fe_bh, 215 struct ocfs2_truncate_context *tc); 216 int ocfs2_truncate_inline(struct inode *inode, struct buffer_head *di_bh, 217 unsigned int start, unsigned int end, int trunc); 218 219 int ocfs2_find_leaf(struct inode *inode, struct ocfs2_extent_list *root_el, 220 u32 cpos, struct buffer_head **leaf_bh); 221 int ocfs2_search_extent_list(struct ocfs2_extent_list *el, u32 v_cluster); 222 223 /* 224 * Helper function to look at the # of clusters in an extent record. 225 */ 226 static inline unsigned int ocfs2_rec_clusters(struct ocfs2_extent_list *el, 227 struct ocfs2_extent_rec *rec) 228 { 229 /* 230 * Cluster count in extent records is slightly different 231 * between interior nodes and leaf nodes. This is to support 232 * unwritten extents which need a flags field in leaf node 233 * records, thus shrinking the available space for a clusters 234 * field. 235 */ 236 if (el->l_tree_depth) 237 return le32_to_cpu(rec->e_int_clusters); 238 else 239 return le16_to_cpu(rec->e_leaf_clusters); 240 } 241 242 /* 243 * This is only valid for leaf nodes, which are the only ones that can 244 * have empty extents anyway. 245 */ 246 static inline int ocfs2_is_empty_extent(struct ocfs2_extent_rec *rec) 247 { 248 return !rec->e_leaf_clusters; 249 } 250 251 #endif /* OCFS2_ALLOC_H */ 252