fs/ocfs2/move_extents.c

   1 /* -*- mode: c; c-basic-offset: 8; -*-
   2  * vim: noexpandtab sw=8 ts=8 sts=0:
   3  *
   4  * move_extents.c
   5  *
   6  * Copyright (C) 2011 Oracle.  All rights reserved.
   7  *
   8  * This program is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU General Public
  10  * License version 2 as published by the Free Software Foundation.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * General Public License for more details.
  16  */
  17 #include <linux/fs.h>
  18 #include <linux/types.h>
  19 #include <linux/mount.h>
  20 #include <linux/swap.h>
  21
  22 #include <cluster/masklog.h>
  23
  24 #include "ocfs2.h"
  25 #include "ocfs2_ioctl.h"
  26
  27 #include "alloc.h"
  28 #include "aops.h"
  29 #include "dlmglue.h"
  30 #include "extent_map.h"
  31 #include "inode.h"
  32 #include "journal.h"
  33 #include "suballoc.h"
  34 #include "uptodate.h"
  35 #include "super.h"
  36 #include "dir.h"
  37 #include "buffer_head_io.h"
  38 #include "sysfile.h"
  39 #include "suballoc.h"
  40 #include "refcounttree.h"
  41 #include "move_extents.h"
  42
  43 struct ocfs2_move_extents_context {
  44         struct inode *inode;
  45         struct file *file;
  46         int auto_defrag;
  47         int credits;
  48         u32 new_phys_cpos;
  49         u32 clusters_moved;
  50         u64 refcount_loc;
  51         struct ocfs2_move_extents *range;
  52         struct ocfs2_extent_tree et;
  53         struct ocfs2_alloc_context *meta_ac;
  54         struct ocfs2_alloc_context *data_ac;
  55         struct ocfs2_cached_dealloc_ctxt dealloc;
  56 };
  57
  58 static int __ocfs2_move_extent(handle_t *handle,
  59                                struct ocfs2_move_extents_context *context,
  60                                u32 cpos, u32 len, u32 p_cpos, u32 new_p_cpos,
  61                                int ext_flags)
  62 {
  63         int ret = 0, index;
  64         struct inode *inode = context->inode;
  65         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
  66         struct ocfs2_extent_rec *rec, replace_rec;
  67         struct ocfs2_path *path = NULL;
  68         struct ocfs2_extent_list *el;
  69         u64 ino = ocfs2_metadata_cache_owner(context->et.et_ci);
  70         u64 old_blkno = ocfs2_clusters_to_blocks(inode->i_sb, p_cpos);
  71
  72         ret = ocfs2_duplicate_clusters_by_page(handle, context->file, cpos,
  73                                                p_cpos, new_p_cpos, len);
  74         if (ret) {
  75                 mlog_errno(ret);
  76                 goto out;
  77         }
  78
  79         memset(&replace_rec, 0, sizeof(replace_rec));
  80         replace_rec.e_cpos = cpu_to_le32(cpos);
  81         replace_rec.e_leaf_clusters = cpu_to_le16(len);
  82         replace_rec.e_blkno = cpu_to_le64(ocfs2_clusters_to_blocks(inode->i_sb,
  83                                                                    new_p_cpos));
  84
  85         path = ocfs2_new_path_from_et(&context->et);
  86         if (!path) {
  87                 ret = -ENOMEM;
  88                 mlog_errno(ret);
  89                 goto out;
  90         }
  91
  92         ret = ocfs2_find_path(INODE_CACHE(inode), path, cpos);
  93         if (ret) {
  94                 mlog_errno(ret);
  95                 goto out;
  96         }
  97
  98         el = path_leaf_el(path);
  99
 100         index = ocfs2_search_extent_list(el, cpos);
 101         if (index == -1 || index >= le16_to_cpu(el->l_next_free_rec)) {
 102                 ocfs2_error(inode->i_sb,
 103                             "Inode %llu has an extent at cpos %u which can no "
 104                             "longer be found.\n",
 105                             (unsigned long long)ino, cpos);
 106                 ret = -EROFS;
 107                 goto out;
 108         }
 109
 110         rec = &el->l_recs[index];
 111
 112         BUG_ON(ext_flags != rec->e_flags);
 113         /*
 114          * after moving/defraging to new location, the extent is not going
 115          * to be refcounted anymore.
 116          */
 117         replace_rec.e_flags = ext_flags & ~OCFS2_EXT_REFCOUNTED;
 118
 119         ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode),
 120                                       context->et.et_root_bh,
 121                                       OCFS2_JOURNAL_ACCESS_WRITE);
 122         if (ret) {
 123                 mlog_errno(ret);
 124                 goto out;
 125         }
 126
 127         ret = ocfs2_split_extent(handle, &context->et, path, index,
 128                                  &replace_rec, context->meta_ac,
 129                                  &context->dealloc);
 130         if (ret) {
 131                 mlog_errno(ret);
 132                 goto out;
 133         }
 134
 135         ocfs2_journal_dirty(handle, context->et.et_root_bh);
 136
 137         context->new_phys_cpos = new_p_cpos;
 138
 139         /*
 140          * need I to append truncate log for old clusters?
 141          */
 142         if (old_blkno) {
 143                 if (ext_flags & OCFS2_EXT_REFCOUNTED)
 144                         ret = ocfs2_decrease_refcount(inode, handle,
 145                                         ocfs2_blocks_to_clusters(osb->sb,
 146                                                                  old_blkno),
 147                                         len, context->meta_ac,
 148                                         &context->dealloc, 1);
 149                 else
 150                         ret = ocfs2_truncate_log_append(osb, handle,
 151                                                         old_blkno, len);
 152         }
 153
 154 out:
 155         return ret;
 156 }
 157
 158 /*
 159  * lock allocators, and reserving appropriate number of bits for
 160  * meta blocks and data clusters.
 161  *
 162  * in some cases, we don't need to reserve clusters, just let data_ac
 163  * be NULL.
 164  */
 165 static int ocfs2_lock_allocators_move_extents(struct inode *inode,
 166                                         struct ocfs2_extent_tree *et,
 167                                         u32 clusters_to_move,
 168                                         u32 extents_to_split,
 169                                         struct ocfs2_alloc_context **meta_ac,
 170                                         struct ocfs2_alloc_context **data_ac,
 171                                         int extra_blocks,
 172                                         int *credits)
 173 {
 174         int ret, num_free_extents;
 175         unsigned int max_recs_needed = 2 * extents_to_split + clusters_to_move;
 176         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 177
 178         num_free_extents = ocfs2_num_free_extents(osb, et);
 179         if (num_free_extents < 0) {
 180                 ret = num_free_extents;
 181                 mlog_errno(ret);
 182                 goto out;
 183         }
 184
 185         if (!num_free_extents ||
 186             (ocfs2_sparse_alloc(osb) && num_free_extents < max_recs_needed))
 187                 extra_blocks += ocfs2_extend_meta_needed(et->et_root_el);
 188
 189         ret = ocfs2_reserve_new_metadata_blocks(osb, extra_blocks, meta_ac);
 190         if (ret) {
 191                 mlog_errno(ret);
 192                 goto out;
 193         }
 194
 195         if (data_ac) {
 196                 ret = ocfs2_reserve_clusters(osb, clusters_to_move, data_ac);
 197                 if (ret) {
 198                         mlog_errno(ret);
 199                         goto out;
 200                 }
 201         }
 202
 203         *credits += ocfs2_calc_extend_credits(osb->sb, et->et_root_el,
 204                                               clusters_to_move + 2);
 205
 206         mlog(0, "reserve metadata_blocks: %d, data_clusters: %u, credits: %d\n",
 207              extra_blocks, clusters_to_move, *credits);
 208 out:
 209         if (ret) {
 210                 if (*meta_ac) {
 211                         ocfs2_free_alloc_context(*meta_ac);
 212                         *meta_ac = NULL;
 213                 }
 214         }
 215
 216         return ret;
 217 }