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
  29 struct ocfs2_suballoc_result;
  30 typedef 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
  38 struct 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
  65 void ocfs2_init_steal_slots(struct ocfs2_super *osb);
  66 void ocfs2_free_alloc_context(struct ocfs2_alloc_context *ac);
  67 static 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  */
  77 int ocfs2_reserve_new_metadata(struct ocfs2_super *osb,
  78                                struct ocfs2_extent_list *root_el,
  79                                struct ocfs2_alloc_context **ac);
  80 int ocfs2_reserve_new_metadata_blocks(struct ocfs2_super *osb,
  81                                       int blocks,
  82                                       struct ocfs2_alloc_context **ac);
  83 int ocfs2_reserve_new_inode(struct ocfs2_super *osb,
  84                             struct ocfs2_alloc_context **ac);
  85 int ocfs2_reserve_clusters(struct ocfs2_super *osb,
  86                            u32 bits_wanted,
  87                            struct ocfs2_alloc_context **ac);
  88
  89 int 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);
  96 int 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);
 103 int 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  */
 112 int __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
 119 int 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);
 125 int ocfs2_free_dinode(handle_t *handle,
 126                       struct inode *inode_alloc_inode,
 127                       struct buffer_head *inode_alloc_bh,
 128                       struct ocfs2_dinode *di);
 129 int 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);
 134 int 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
 140 static inline u64 ocfs2_which_suballoc_group(u64 block, unsigned int bit)
 141 {
 142         u64 group = block - (u64) bit;
 143
 144         return group;
 145 }
 146
 147 static 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
 163 static 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. */
 171 int ocfs2_reserve_cluster_bitmap_bits(struct ocfs2_super *osb,
 172                                       struct ocfs2_alloc_context *ac);
 173 void 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. */
 177 u64 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  */
 186 int 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  */
 194 int ocfs2_read_group_descriptor(struct inode *inode, struct ocfs2_dinode *di,
 195                                 u64 gd_blkno, struct buffer_head **bh);
 196
 197 int 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
 202 int 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  */
 209 int 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
 214 int 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_ */