sbin/hammer/blockmap.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/sbin/hammer/blockmap.c,v 1.2 2008/06/17 04:03:38 dillon Exp $
  35  */
  36
  37 #include "hammer_util.h"
  38
  39 /*
  40  * Allocate big-blocks using our poor-man's volume->vol_free_off.
  41  * We are bootstrapping the freemap itself and cannot update it yet.
  42  */
  43 hammer_off_t
  44 bootstrap_bigblock(volume_info_t volume)
  45 {
  46         hammer_off_t result_offset;
  47
  48         assert_volume_offset(volume);
  49         result_offset = volume->vol_free_off;
  50
  51         volume->vol_free_off += HAMMER_BIGBLOCK_SIZE;
  52
  53         return(result_offset);
  54 }
  55
  56 /*
  57  * Allocate a big-block for zone-3 for UNDO/REDO FIFO.
  58  */
  59 hammer_off_t
  60 alloc_undo_bigblock(volume_info_t volume)
  61 {
  62         hammer_blockmap_t freemap;
  63         buffer_info_t buffer1 = NULL;
  64         buffer_info_t buffer2 = NULL;
  65         hammer_blockmap_layer1_t layer1;
  66         hammer_blockmap_layer2_t layer2;
  67         hammer_off_t layer1_offset;
  68         hammer_off_t layer2_offset;
  69         hammer_off_t result_offset;
  70
  71         /* Only root volume needs formatting */
  72         assert(volume->vol_no == HAMMER_ROOT_VOLNO);
  73
  74         result_offset = bootstrap_bigblock(volume);
  75         freemap = &volume->ondisk->vol0_blockmap[HAMMER_ZONE_FREEMAP_INDEX];
  76
  77         /*
  78          * Dive layer 1.
  79          */
  80         layer1_offset = freemap->phys_offset +
  81                         HAMMER_BLOCKMAP_LAYER1_OFFSET(result_offset);
  82         layer1 = get_buffer_data(layer1_offset, &buffer1, 0);
  83         assert(layer1->phys_offset != HAMMER_BLOCKMAP_UNAVAIL);
  84         --layer1->blocks_free;
  85         hammer_crc_set_layer1(HammerVersion, layer1);
  86         buffer1->cache.modified = 1;
  87
  88         /*
  89          * Dive layer 2, each entry represents a big-block.
  90          */
  91         layer2_offset = layer1->phys_offset +
  92                         HAMMER_BLOCKMAP_LAYER2_OFFSET(result_offset);
  93         layer2 = get_buffer_data(layer2_offset, &buffer2, 0);
  94         assert(layer2->zone == 0);
  95         layer2->zone = HAMMER_ZONE_UNDO_INDEX;
  96         layer2->append_off = HAMMER_BIGBLOCK_SIZE;
  97         layer2->bytes_free = 0;
  98         hammer_crc_set_layer2(HammerVersion, layer2);
  99         buffer2->cache.modified = 1;
 100
 101         --volume->ondisk->vol0_stat_freebigblocks;
 102
 103         rel_buffer(buffer1);
 104         rel_buffer(buffer2);
 105
 106         return(result_offset);
 107 }
 108
 109 /*
 110  * Allocate a chunk of data out of a blockmap.  This is a simplified
 111  * version which uses next_offset as a simple allocation iterator.
 112  */
 113 void *
 114 alloc_blockmap(int zone, int bytes, hammer_off_t *result_offp,
 115                buffer_info_t *bufferp)
 116 {
 117         volume_info_t volume;
 118         hammer_blockmap_t blockmap;
 119         hammer_blockmap_t freemap;
 120         buffer_info_t buffer1 = NULL;
 121         buffer_info_t buffer2 = NULL;
 122         hammer_blockmap_layer1_t layer1;
 123         hammer_blockmap_layer2_t layer2;
 124         hammer_off_t tmp_offset;
 125         hammer_off_t layer1_offset;
 126         hammer_off_t layer2_offset;
 127         void *ptr;
 128
 129         volume = get_root_volume();
 130
 131         blockmap = &volume->ondisk->vol0_blockmap[zone];
 132         freemap = &volume->ondisk->vol0_blockmap[HAMMER_ZONE_FREEMAP_INDEX];
 133         assert(HAMMER_ZONE_DECODE(blockmap->next_offset) == zone);
 134
 135         /*
 136          * Alignment and buffer-boundary issues.  If the allocation would
 137          * cross a buffer boundary we have to skip to the next buffer.
 138          */
 139         bytes = HAMMER_DATA_DOALIGN(bytes);
 140         assert(bytes > 0 && bytes <= HAMMER_BUFSIZE);  /* not HAMMER_XBUFSIZE */
 141         assert(hammer_is_index_record(zone));
 142
 143 again:
 144         assert(blockmap->next_offset != HAMMER_ZONE_ENCODE(zone + 1, 0));
 145
 146         tmp_offset = blockmap->next_offset + bytes - 1;
 147         if ((blockmap->next_offset ^ tmp_offset) & ~HAMMER_BUFMASK64)
 148                 blockmap->next_offset = tmp_offset & ~HAMMER_BUFMASK64;
 149
 150         /*
 151          * Dive layer 1.
 152          */
 153         layer1_offset = freemap->phys_offset +
 154                         HAMMER_BLOCKMAP_LAYER1_OFFSET(blockmap->next_offset);
 155         layer1 = get_buffer_data(layer1_offset, &buffer1, 0);
 156         assert(layer1->phys_offset != HAMMER_BLOCKMAP_UNAVAIL);
 157         assert(!((blockmap->next_offset & HAMMER_BIGBLOCK_MASK) == 0 &&
 158                 layer1->blocks_free == 0));
 159
 160         /*
 161          * Dive layer 2, each entry represents a big-block.
 162          */
 163         layer2_offset = layer1->phys_offset +
 164                         HAMMER_BLOCKMAP_LAYER2_OFFSET(blockmap->next_offset);
 165         layer2 = get_buffer_data(layer2_offset, &buffer2, 0);
 166
 167         if (layer2->zone == HAMMER_ZONE_UNAVAIL_INDEX) {
 168                 errx(1, "alloc_blockmap: layer2 ran out of space!");
 169                 /* not reached */
 170         }
 171
 172         /*
 173          * If we are entering a new big-block assign ownership to our
 174          * zone.  If the big-block is owned by another zone skip it.
 175          */
 176         if (layer2->zone == 0) {
 177                 --layer1->blocks_free;
 178                 hammer_crc_set_layer1(HammerVersion, layer1);
 179                 layer2->zone = zone;
 180                 --volume->ondisk->vol0_stat_freebigblocks;
 181                 assert(layer2->bytes_free == HAMMER_BIGBLOCK_SIZE);
 182                 assert(layer2->append_off == 0);
 183         }
 184         if (layer2->zone != zone) {
 185                 blockmap->next_offset =
 186                         HAMMER_ZONE_LAYER2_NEXT_OFFSET(blockmap->next_offset);
 187                 goto again;
 188         }
 189
 190         assert(layer2->append_off ==
 191                 (blockmap->next_offset & HAMMER_BIGBLOCK_MASK));
 192         layer2->bytes_free -= bytes;
 193         *result_offp = blockmap->next_offset;
 194         blockmap->next_offset += bytes;
 195         layer2->append_off = (int)blockmap->next_offset & HAMMER_BIGBLOCK_MASK;
 196         hammer_crc_set_layer2(HammerVersion, layer2);
 197
 198         ptr = get_buffer_data(*result_offp, bufferp, 0);
 199         (*bufferp)->cache.modified = 1;
 200
 201         buffer1->cache.modified = 1;
 202         buffer2->cache.modified = 1;
 203
 204         rel_buffer(buffer1);
 205         rel_buffer(buffer2);
 206         return(ptr);
 207 }
 208
 209 hammer_off_t
 210 blockmap_lookup(hammer_off_t zone_offset, int *errorp)
 211 {
 212         return(blockmap_lookup_save(zone_offset, NULL, NULL, errorp));
 213 }
 214
 215 hammer_off_t
 216 blockmap_lookup_save(hammer_off_t zone_offset,
 217                 hammer_blockmap_layer1_t save_layer1,
 218                 hammer_blockmap_layer2_t save_layer2,
 219                 int *errorp)
 220 {
 221         volume_info_t root_volume = NULL;
 222         hammer_volume_ondisk_t ondisk;
 223         hammer_blockmap_t blockmap;
 224         hammer_blockmap_t freemap;
 225         hammer_blockmap_layer1_t layer1;
 226         hammer_blockmap_layer2_t layer2;
 227         buffer_info_t buffer1 = NULL;
 228         buffer_info_t buffer2 = NULL;
 229         hammer_off_t layer1_offset;
 230         hammer_off_t layer2_offset;
 231         hammer_off_t result_offset = HAMMER_OFF_BAD;;
 232         int zone;
 233         int error = 0;
 234
 235         if (save_layer1)
 236                 bzero(save_layer1, sizeof(*save_layer1));
 237         if (save_layer2)
 238                 bzero(save_layer2, sizeof(*save_layer2));
 239
 240         zone = HAMMER_ZONE_DECODE(zone_offset);
 241
 242         if (zone <= HAMMER_ZONE_RAW_VOLUME_INDEX) {
 243                 error = -1;
 244                 goto done;
 245         }
 246         if (zone >= HAMMER_MAX_ZONES) {
 247                 error = -2;
 248                 goto done;
 249         }
 250
 251         root_volume = get_root_volume();
 252         ondisk = root_volume->ondisk;
 253         blockmap = &ondisk->vol0_blockmap[zone];
 254
 255         /*
 256          * Handle blockmap offset translations.
 257          */
 258         if (hammer_is_index_record(zone)) {
 259                 result_offset = hammer_xlate_to_zone2(zone_offset);
 260         } else if (zone == HAMMER_ZONE_UNDO_INDEX) {
 261                 if (zone_offset >= blockmap->alloc_offset) {
 262                         error = -3;
 263                         goto done;
 264                 }
 265                 result_offset = hammer_xlate_to_undo(ondisk, zone_offset);
 266         } else {
 267                 /* assert(zone == HAMMER_ZONE_RAW_BUFFER_INDEX); */
 268                 result_offset = zone_offset;
 269         }
 270
 271         /*
 272          * The blockmap should match the requested zone (else the volume
 273          * header is mashed).
 274          */
 275         if (hammer_is_index_record(zone) &&
 276             HAMMER_ZONE_DECODE(blockmap->alloc_offset) != zone) {
 277                 error = -4;
 278                 goto done;
 279         }
 280
 281         /*
 282          * Validate that the big-block is assigned to the zone.  Also
 283          * assign save_layer{1,2} if not NULL.
 284          */
 285         freemap = &ondisk->vol0_blockmap[HAMMER_ZONE_FREEMAP_INDEX];
 286
 287         /*
 288          * Dive layer 1.
 289          */
 290         layer1_offset = freemap->phys_offset +
 291                         HAMMER_BLOCKMAP_LAYER1_OFFSET(result_offset);
 292         layer1 = get_buffer_data(layer1_offset, &buffer1, 0);
 293
 294         if (layer1 == NULL) {
 295                 error = -5;
 296                 goto done;
 297         }
 298         if (layer1->phys_offset == HAMMER_BLOCKMAP_UNAVAIL) {
 299                 error = -6;
 300                 goto done;
 301         }
 302         if (save_layer1)
 303                 *save_layer1 = *layer1;
 304
 305         /*
 306          * Dive layer 2, each entry represents a big-block.
 307          */
 308         layer2_offset = layer1->phys_offset +
 309                         HAMMER_BLOCKMAP_LAYER2_OFFSET(result_offset);
 310         layer2 = get_buffer_data(layer2_offset, &buffer2, 0);
 311
 312         if (layer2 == NULL) {
 313                 error = -7;
 314                 goto done;
 315         }
 316         if (layer2->zone != zone) {
 317                 error = -8;
 318                 goto done;
 319         }
 320         if (save_layer2)
 321                 *save_layer2 = *layer2;
 322
 323 done:
 324         rel_buffer(buffer1);
 325         rel_buffer(buffer2);
 326
 327         if (errorp)
 328                 *errorp = error;
 329
 330         return(result_offset);
 331 }
 332