sys/vfs/hammer/hammer_reblock.c

   1 /*
   2  * Copyright (c) 2008 The DragonFly Project.  All rights reserved.
   3  *
   4  * This code is derived from software contributed to The DragonFly Project
   5  * by Matthew Dillon <dillon@backplane.com>
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  *
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in
  15  *    the documentation and/or other materials provided with the
  16  *    distribution.
  17  * 3. Neither the name of The DragonFly Project nor the names of its
  18  *    contributors may be used to endorse or promote products derived
  19  *    from this software without specific, prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  23  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  24  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
  25  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  26  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
  27  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  28  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  29  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  31  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  *
  34  * $DragonFly: src/sys/vfs/hammer/hammer_reblock.c,v 1.6 2008/03/26 04:32:54 dillon Exp $
  35  */
  36 /*
  37  * HAMMER reblocker - This code frees up fragmented physical space
  38  *
  39  * HAMMER only keeps track of free space on a big-block basis.  A big-block
  40  * containing holes can only be freed by migrating the remaining data in
  41  * that big-block into a new big-block, then freeing the big-block.
  42  *
  43  * This function is called from an ioctl or via the hammer support thread.
  44  */
  45
  46 #include "hammer.h"
  47
  48 static int hammer_reblock_helper(struct hammer_ioc_reblock *reblock,
  49                                  hammer_cursor_t cursor,
  50                                  hammer_btree_elm_t elm);
  51 static int hammer_reblock_data(struct hammer_ioc_reblock *reblock,
  52                                 hammer_cursor_t cursor, hammer_btree_elm_t elm);
  53 static int hammer_reblock_record(struct hammer_ioc_reblock *reblock,
  54                                 hammer_cursor_t cursor, hammer_btree_elm_t elm);
  55 static int hammer_reblock_node(struct hammer_ioc_reblock *reblock,
  56                                 hammer_cursor_t cursor, hammer_btree_elm_t elm);
  57
  58 int
  59 hammer_ioc_reblock(hammer_transaction_t trans, hammer_inode_t ip,
  60                struct hammer_ioc_reblock *reblock)
  61 {
  62         struct hammer_cursor cursor;
  63         hammer_btree_elm_t elm;
  64         int error;
  65
  66         if (reblock->beg_obj_id >= reblock->end_obj_id)
  67                 return(EINVAL);
  68         if (reblock->free_level < 0)
  69                 return(EINVAL);
  70
  71 retry:
  72         error = hammer_init_cursor(trans, &cursor, NULL);
  73         if (error) {
  74                 hammer_done_cursor(&cursor);
  75                 return(error);
  76         }
  77         cursor.key_beg.obj_id = reblock->cur_obj_id;
  78         cursor.key_beg.key = HAMMER_MIN_KEY;
  79         cursor.key_beg.create_tid = 1;
  80         cursor.key_beg.delete_tid = 0;
  81         cursor.key_beg.rec_type = HAMMER_MIN_RECTYPE;
  82         cursor.key_beg.obj_type = 0;
  83
  84         cursor.key_end.obj_id = reblock->end_obj_id;
  85         cursor.key_end.key = HAMMER_MAX_KEY;
  86         cursor.key_end.create_tid = HAMMER_MAX_TID - 1;
  87         cursor.key_end.delete_tid = 0;
  88         cursor.key_end.rec_type = HAMMER_MAX_RECTYPE;
  89         cursor.key_end.obj_type = 0;
  90
  91         cursor.flags |= HAMMER_CURSOR_END_INCLUSIVE;
  92
  93         error = hammer_btree_first(&cursor);
  94         while (error == 0) {
  95                 elm = &cursor.node->ondisk->elms[cursor.index];
  96                 reblock->cur_obj_id = elm->base.obj_id;
  97
  98                 error = hammer_reblock_helper(reblock, &cursor, elm);
  99                 if (error == 0) {
 100                         cursor.flags |= HAMMER_CURSOR_ATEDISK;
 101                         error = hammer_btree_iterate(&cursor);
 102                 }
 103                 if (error == 0)
 104                         error = hammer_signal_check(trans->hmp);
 105         }
 106         if (error == ENOENT)
 107                 error = 0;
 108         hammer_done_cursor(&cursor);
 109         if (error == EDEADLK)
 110                 goto retry;
 111         return(error);
 112 }
 113
 114 /*
 115  * Reblock the B-Tree (leaf) node, record, and/or data if necessary.
 116  *
 117  * XXX We have no visibility into internal B-Tree nodes at the moment.
 118  */
 119 static int
 120 hammer_reblock_helper(struct hammer_ioc_reblock *reblock,
 121                       hammer_cursor_t cursor, hammer_btree_elm_t elm)
 122 {
 123         hammer_off_t tmp_offset;
 124         int error;
 125         int zone;
 126         int bytes;
 127         int cur;
 128
 129         if (elm->leaf.base.btype != HAMMER_BTREE_TYPE_RECORD)
 130                 return(0);
 131         error = 0;
 132
 133         /*
 134          * Reblock data.  Note that data embedded in a record is reblocked
 135          * by the record reblock code.
 136          */
 137         tmp_offset = elm->leaf.data_offset;
 138         zone = HAMMER_ZONE_DECODE(tmp_offset);          /* can be 0 */
 139         if ((zone == HAMMER_ZONE_SMALL_DATA_INDEX ||
 140              zone == HAMMER_ZONE_LARGE_DATA_INDEX) && error == 0) {
 141                 ++reblock->data_count;
 142                 reblock->data_byte_count += elm->leaf.data_len;
 143                 bytes = hammer_blockmap_getfree(cursor->trans->hmp, tmp_offset,
 144                                                 &cur, &error);
 145                 if (error == 0 && cur == 0 && bytes > reblock->free_level) {
 146                         if (hammer_debug_general & 0x4000)
 147                                 kprintf("%6d ", bytes);
 148                         error = hammer_cursor_upgrade(cursor);
 149                         if (error == 0) {
 150                                 error = hammer_reblock_data(reblock,
 151                                                             cursor, elm);
 152                         }
 153                         if (error == 0) {
 154                                 ++reblock->data_moves;
 155                                 reblock->data_byte_moves += elm->leaf.data_len;
 156                         }
 157                 }
 158         }
 159
 160         /*
 161          * Reblock a record
 162          */
 163         tmp_offset = elm->leaf.rec_offset;
 164         zone = HAMMER_ZONE_DECODE(tmp_offset);
 165         if (zone == HAMMER_ZONE_RECORD_INDEX && error == 0) {
 166                 ++reblock->record_count;
 167                 bytes = hammer_blockmap_getfree(cursor->trans->hmp, tmp_offset,
 168                                                 &cur, &error);
 169                 if (error == 0 && cur == 0 && bytes > reblock->free_level) {
 170                         if (hammer_debug_general & 0x4000)
 171                                 kprintf("%6d ", bytes);
 172                         error = hammer_cursor_upgrade(cursor);
 173                         if (error == 0) {
 174                                 error = hammer_reblock_record(reblock,
 175                                                               cursor, elm);
 176                         }
 177                         if (error == 0) {
 178                                 ++reblock->record_moves;
 179                         }
 180                 }
 181         }
 182
 183         /*
 184          * Reblock a B-Tree node.  Adjust elm to point at the parent's
 185          * leaf entry.
 186          */
 187         tmp_offset = cursor->node->node_offset;
 188         zone = HAMMER_ZONE_DECODE(tmp_offset);
 189         if (zone == HAMMER_ZONE_BTREE_INDEX && error == 0 &&
 190             cursor->index == 0) {
 191                 ++reblock->btree_count;
 192                 bytes = hammer_blockmap_getfree(cursor->trans->hmp, tmp_offset,
 193                                                 &cur, &error);
 194                 if (error == 0 && cur == 0 && bytes > reblock->free_level) {
 195                         if (hammer_debug_general & 0x4000)
 196                                 kprintf("%6d ", bytes);
 197                         error = hammer_cursor_upgrade(cursor);
 198                         if (error == 0) {
 199                                 if (cursor->parent)
 200                                         elm = &cursor->parent->ondisk->elms[cursor->parent_index];
 201                                 else
 202                                         elm = NULL;
 203                                 error = hammer_reblock_node(reblock,
 204                                                             cursor, elm);
 205                         }
 206                         if (error == 0) {
 207                                 ++reblock->btree_moves;
 208                         }
 209                 }
 210         }
 211
 212         hammer_cursor_downgrade(cursor);
 213         return(error);
 214 }
 215
 216 /*
 217  * Reblock a record's data.  Both the B-Tree element and record pointers
 218  * to the data must be adjusted.
 219  */
 220 static int
 221 hammer_reblock_data(struct hammer_ioc_reblock *reblock,
 222                     hammer_cursor_t cursor, hammer_btree_elm_t elm)
 223 {
 224         struct hammer_buffer *data_buffer = NULL;
 225         hammer_off_t ndata_offset;
 226         int error;
 227         void *ndata;
 228
 229         error = hammer_btree_extract(cursor, HAMMER_CURSOR_GET_DATA |
 230                                              HAMMER_CURSOR_GET_RECORD);
 231         if (error)
 232                 return (error);
 233         ndata = hammer_alloc_data(cursor->trans, elm->leaf.data_len,
 234                                   &ndata_offset, &data_buffer, &error);
 235         if (error)
 236                 goto done;
 237
 238         /*
 239          * Move the data
 240          */
 241         bcopy(cursor->data, ndata, elm->leaf.data_len);
 242         hammer_modify_node(cursor->trans, cursor->node,
 243                            &elm->leaf.data_offset, sizeof(hammer_off_t));
 244         hammer_modify_record(cursor->trans, cursor->record_buffer,
 245                              &cursor->record->base.data_off,
 246                              sizeof(hammer_off_t));
 247
 248         hammer_blockmap_free(cursor->trans,
 249                              elm->leaf.data_offset, elm->leaf.data_len);
 250
 251         cursor->record->base.data_off = ndata_offset;
 252         elm->leaf.data_offset = ndata_offset;
 253
 254 done:
 255         if (data_buffer)
 256                 hammer_rel_buffer(data_buffer, 0);
 257         return (error);
 258 }
 259
 260 /*
 261  * Reblock a record.  The B-Tree must be adjusted to point to the new record
 262  * and the existing record must be physically destroyed so a FS rebuild
 263  * does not see two versions of the same record.
 264  */
 265 static int
 266 hammer_reblock_record(struct hammer_ioc_reblock *reblock,
 267                       hammer_cursor_t cursor, hammer_btree_elm_t elm)
 268 {
 269         struct hammer_buffer *rec_buffer = NULL;
 270         hammer_off_t nrec_offset;
 271         hammer_off_t ndata_offset;
 272         hammer_record_ondisk_t orec;
 273         hammer_record_ondisk_t nrec;
 274         int error;
 275         int inline_data;
 276
 277         error = hammer_btree_extract(cursor, HAMMER_CURSOR_GET_RECORD);
 278         if (error)
 279                 return (error);
 280
 281         nrec = hammer_alloc_record(cursor->trans, &nrec_offset,
 282                                    elm->leaf.base.rec_type, &rec_buffer,
 283                                    0, NULL, NULL, &error);
 284         if (error)
 285                 goto done;
 286
 287         /*
 288          * Move the record.  Check for an inline data reference and move that
 289          * too if necessary.
 290          */
 291         orec = cursor->record;
 292         bcopy(orec, nrec, sizeof(*nrec));
 293
 294         if ((orec->base.data_off & HAMMER_OFF_ZONE_MASK) == HAMMER_ZONE_RECORD) {
 295                 ndata_offset = orec->base.data_off - elm->leaf.rec_offset;
 296                 KKASSERT(ndata_offset < sizeof(*nrec));
 297                 ndata_offset += nrec_offset;
 298                 inline_data = 1;
 299         } else {
 300                 ndata_offset = 0;
 301                 inline_data = 0;
 302         }
 303
 304         hammer_modify_record(cursor->trans, cursor->record_buffer,
 305                              &orec->base.base.rec_type,
 306                              sizeof(orec->base.base.rec_type));
 307         orec->base.base.rec_type |= HAMMER_RECTYPE_MOVED;
 308
 309         hammer_blockmap_free(cursor->trans,
 310                              elm->leaf.rec_offset, sizeof(*nrec));
 311
 312         if (hammer_debug_general & 0x4000) {
 313                 kprintf("REBLOCK RECD %016llx -> %016llx\n",
 314                         elm->leaf.rec_offset, nrec_offset);
 315         }
 316
 317         hammer_modify_node(cursor->trans, cursor->node,
 318                            &elm->leaf.rec_offset, sizeof(hammer_off_t));
 319         elm->leaf.rec_offset = nrec_offset;
 320         if (inline_data) {
 321                 hammer_modify_node(cursor->trans, cursor->node,
 322                                  &elm->leaf.data_offset, sizeof(hammer_off_t));
 323                 elm->leaf.data_offset = ndata_offset;
 324                 nrec->base.data_off = ndata_offset;
 325         }
 326
 327 done:
 328         if (rec_buffer)
 329                 hammer_rel_buffer(rec_buffer, 0);
 330         return (error);
 331 }
 332
 333 /*
 334  * Reblock a B-Tree (leaf) node.  The parent must be adjusted to point to
 335  * the new copy of the leaf node.  elm is a pointer to the parent element
 336  * pointing at cursor.node.
 337  *
 338  * XXX reblock internal nodes too.
 339  */
 340 static int
 341 hammer_reblock_node(struct hammer_ioc_reblock *reblock,
 342                     hammer_cursor_t cursor, hammer_btree_elm_t elm)
 343 {
 344         hammer_node_t onode;
 345         hammer_node_t nnode;
 346         int error;
 347
 348         onode = cursor->node;
 349         nnode = hammer_alloc_btree(cursor->trans, &error);
 350         hammer_lock_ex(&nnode->lock);
 351
 352         if (nnode == NULL)
 353                 return (error);
 354
 355         /*
 356          * Move the node
 357          */
 358         bcopy(onode->ondisk, nnode->ondisk, sizeof(*nnode->ondisk));
 359
 360         if (elm) {
 361                 /*
 362                  * We are not the root of the B-Tree
 363                  */
 364                 hammer_modify_node(cursor->trans, cursor->parent,
 365                                    &elm->internal.subtree_offset,
 366                                    sizeof(elm->internal.subtree_offset));
 367                 elm->internal.subtree_offset = nnode->node_offset;
 368         } else {
 369                 /*
 370                  * We are the root of the B-Tree
 371                  */
 372                 hammer_volume_t volume;
 373
 374                 volume = hammer_get_root_volume(cursor->trans->hmp, &error);
 375                 KKASSERT(error == 0);
 376
 377                 hammer_modify_volume(cursor->trans, volume,
 378                                      &volume->ondisk->vol0_btree_root,
 379                                      sizeof(hammer_off_t));
 380                 volume->ondisk->vol0_btree_root = nnode->node_offset;
 381                 hammer_rel_volume(volume, 0);
 382         }
 383
 384         hammer_delete_node(cursor->trans, onode);
 385
 386         if (hammer_debug_general & 0x4000) {
 387                 kprintf("REBLOCK NODE %016llx -> %016llx\n",
 388                         onode->node_offset, nnode->node_offset);
 389         }
 390
 391         cursor->node = nnode;
 392         hammer_rel_node(onode);
 393
 394         return (error);
 395 }
 396