LXR linux/fs/ocfs2/suballoc.h

   1/* -*- mode: c; c-basic-offset: 8; -*-
   2 * vim: noexpandtab sw=8 ts=8 sts=0:
   3 *
   4 * suballoc.h
   5 *
   6 * Defines sub allocator api
   7 *
   8 * Copyright (C) 2003, 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 _CHAINALLOC_H_
  27#define _CHAINALLOC_H_
  28
  29struct ocfs2_suballoc_result;
  30typedef int (group_search_t)(struct inode *,
  31                             struct buffer_head *,
  32                             u32,                       /* bits_wanted */
  33                             u32,                       /* min_bits */
  34                             u64,                       /* max_block */
  35                             struct ocfs2_suballoc_result *);
  36                                                        /* found bits */
  37
  38struct ocfs2_alloc_context {
  39        struct inode *ac_inode;    /* which bitmap are we allocating from? */
  40        struct buffer_head *ac_bh; /* file entry bh */
  41        u32    ac_alloc_slot;   /* which slot are we allocating from? */
  42        u32    ac_bits_wanted;
  43        u32    ac_bits_given;
  44#define OCFS2_AC_USE_LOCAL 1
  45#define OCFS2_AC_USE_MAIN  2
  46#define OCFS2_AC_USE_INODE 3
  47#define OCFS2_AC_USE_META  4
  48        u32    ac_which;
  49
  50        /* these are used by the chain search */
  51        u16    ac_chain;
  52        int    ac_allow_chain_relink;
  53        group_search_t *ac_group_search;
  54
  55        u64    ac_last_group;
  56        u64    ac_max_block;  /* Highest block number to allocate. 0 is
  57                                 is the same as ~0 - unlimited */
  58
  59        int    ac_find_loc_only;  /* hack for reflink operation ordering */
  60        struct ocfs2_suballoc_result *ac_find_loc_priv; /* */
  61
  62        struct ocfs2_alloc_reservation  *ac_resv;
  63};
  64
  65void ocfs2_init_steal_slots(struct ocfs2_super *osb);
  66void ocfs2_free_alloc_context(struct ocfs2_alloc_context *ac);
  67static inline int ocfs2_alloc_context_bits_left(struct ocfs2_alloc_context *ac)
  68{
  69        return ac->ac_bits_wanted - ac->ac_bits_given;
  70}
  71
  72/*
  73 * Please note that the caller must make sure that root_el is the root
  74 * of extent tree. So for an inode, it should be &fe->id2.i_list. Otherwise
  75 * the result may be wrong.
  76 */
  77int ocfs2_reserve_new_metadata(struct ocfs2_super *osb,
  78                               struct ocfs2_extent_list *root_el,
  79                               struct ocfs2_alloc_context **ac);
  80int ocfs2_reserve_new_metadata_blocks(struct ocfs2_super *osb,
  81                                      int blocks,
  82                                      struct ocfs2_alloc_context **ac);
  83int ocfs2_reserve_new_inode(struct ocfs2_super *osb,
  84                            struct ocfs2_alloc_context **ac);
  85int ocfs2_reserve_clusters(struct ocfs2_super *osb,
  86                           u32 bits_wanted,
  87                           struct ocfs2_alloc_context **ac);
  88
  89int ocfs2_claim_metadata(handle_t *handle,
  90                         struct ocfs2_alloc_context *ac,
  91                         u32 bits_wanted,
  92                         u64 *suballoc_loc,
  93                         u16 *suballoc_bit_start,
  94                         u32 *num_bits,
  95                         u64 *blkno_start);
  96int ocfs2_claim_new_inode(handle_t *handle,
  97                          struct inode *dir,
  98                          struct buffer_head *parent_fe_bh,
  99                          struct ocfs2_alloc_context *ac,
 100                          u64 *suballoc_loc,
 101                          u16 *suballoc_bit,
 102                          u64 *fe_blkno);
 103int ocfs2_claim_clusters(handle_t *handle,
 104                         struct ocfs2_alloc_context *ac,
 105                         u32 min_clusters,
 106                         u32 *cluster_start,
 107                         u32 *num_clusters);
 108/*
 109 * Use this variant of ocfs2_claim_clusters to specify a maxiumum
 110 * number of clusters smaller than the allocation reserved.
 111 */
 112int __ocfs2_claim_clusters(handle_t *handle,
 113                           struct ocfs2_alloc_context *ac,
 114                           u32 min_clusters,
 115                           u32 max_clusters,
 116                           u32 *cluster_start,
 117                           u32 *num_clusters);
 118
 119int ocfs2_free_suballoc_bits(handle_t *handle,
 120                             struct inode *alloc_inode,
 121                             struct buffer_head *alloc_bh,
 122                             unsigned int start_bit,
 123                             u64 bg_blkno,
 124                             unsigned int count);
 125int ocfs2_free_dinode(handle_t *handle,
 126                      struct inode *inode_alloc_inode,
 127                      struct buffer_head *inode_alloc_bh,
 128                      struct ocfs2_dinode *di);
 129int ocfs2_free_clusters(handle_t *handle,
 130                        struct inode *bitmap_inode,
 131                        struct buffer_head *bitmap_bh,
 132                        u64 start_blk,
 133                        unsigned int num_clusters);
 134int ocfs2_release_clusters(handle_t *handle,
 135                           struct inode *bitmap_inode,
 136                           struct buffer_head *bitmap_bh,
 137                           u64 start_blk,
 138                           unsigned int num_clusters);
 139
 140static inline u64 ocfs2_which_suballoc_group(u64 block, unsigned int bit)
 141{
 142        u64 group = block - (u64) bit;
 143
 144        return group;
 145}
 146
 147static inline u32 ocfs2_cluster_from_desc(struct ocfs2_super *osb,
 148                                          u64 bg_blkno)
 149{
 150        /* This should work for all block group descriptors as only
 151         * the 1st group descriptor of the cluster bitmap is
 152         * different. */
 153
 154        if (bg_blkno == osb->first_cluster_group_blkno)
 155                return 0;
 156
 157        /* the rest of the block groups are located at the beginning
 158         * of their 1st cluster, so a direct translation just
 159         * works. */
 160        return ocfs2_blocks_to_clusters(osb->sb, bg_blkno);
 161}
 162
 163static inline int ocfs2_is_cluster_bitmap(struct inode *inode)
 164{
 165        struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 166        return osb->bitmap_blkno == OCFS2_I(inode)->ip_blkno;
 167}
 168
 169/* This is for local alloc ONLY. Others should use the task-specific
 170 * apis above. */
 171int ocfs2_reserve_cluster_bitmap_bits(struct ocfs2_super *osb,
 172                                      struct ocfs2_alloc_context *ac);
 173void ocfs2_free_ac_resource(struct ocfs2_alloc_context *ac);
 174
 175/* given a cluster offset, calculate which block group it belongs to
 176 * and return that block offset. */
 177u64 ocfs2_which_cluster_group(struct inode *inode, u32 cluster);
 178
 179/*
 180 * By default, ocfs2_read_group_descriptor() calls ocfs2_error() when it
 181 * finds a problem.  A caller that wants to check a group descriptor
 182 * without going readonly should read the block with ocfs2_read_block[s]()
 183 * and then checking it with this function.  This is only resize, really.
 184 * Everyone else should be using ocfs2_read_group_descriptor().
 185 */
 186int ocfs2_check_group_descriptor(struct super_block *sb,
 187                                 struct ocfs2_dinode *di,
 188                                 struct buffer_head *bh);
 189/*
 190 * Read a group descriptor block into *bh.  If *bh is NULL, a bh will be
 191 * allocated.  This is a cached read.  The descriptor will be validated with
 192 * ocfs2_validate_group_descriptor().
 193 */
 194int ocfs2_read_group_descriptor(struct inode *inode, struct ocfs2_dinode *di,
 195                                u64 gd_blkno, struct buffer_head **bh);
 196
 197int ocfs2_lock_allocators(struct inode *inode, struct ocfs2_extent_tree *et,
 198                          u32 clusters_to_add, u32 extents_to_split,
 199                          struct ocfs2_alloc_context **data_ac,
 200                          struct ocfs2_alloc_context **meta_ac);
 201
 202int ocfs2_test_inode_bit(struct ocfs2_super *osb, u64 blkno, int *res);
 203
 204
 205
 206/*
 207 * The following two interfaces are for ocfs2_create_inode_in_orphan().
 208 */
 209int ocfs2_find_new_inode_loc(struct inode *dir,
 210                             struct buffer_head *parent_fe_bh,
 211                             struct ocfs2_alloc_context *ac,
 212                             u64 *fe_blkno);
 213
 214int ocfs2_claim_new_inode_at_loc(handle_t *handle,
 215                                 struct inode *dir,
 216                                 struct ocfs2_alloc_context *ac,
 217                                 u64 *suballoc_loc,
 218                                 u16 *suballoc_bit,
 219                                 u64 di_blkno);
 220
 221#endif /* _CHAINALLOC_H_ */
 222