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(struct volume_info *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(struct volume_info *volume)
  61 {
  62         hammer_blockmap_t freemap;
  63         struct buffer_info *buffer1 = NULL;
  64         struct buffer_info *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(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(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                struct buffer_info **bufferp)
 116 {
 117         struct volume_info *volume;
 118         hammer_blockmap_t blockmap;
 119         hammer_blockmap_t freemap;
 120         struct buffer_info *buffer1 = NULL;
 121         struct buffer_info *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         hammer_off_t block_offset;
 128         void *ptr;
 129
 130         volume = get_root_volume();
 131
 132         blockmap = &volume->ondisk->vol0_blockmap[zone];
 133         freemap = &volume->ondisk->vol0_blockmap[HAMMER_ZONE_FREEMAP_INDEX];
 134         assert(HAMMER_ZONE_DECODE(blockmap->next_offset) == zone);
 135
 136         /*
 137          * Alignment and buffer-boundary issues.  If the allocation would
 138          * cross a buffer boundary we have to skip to the next buffer.
 139          */
 140         bytes = HAMMER_DATA_DOALIGN(bytes);
 141         assert(bytes > 0 && bytes <= HAMMER_BUFSIZE);  /* not HAMMER_XBUFSIZE */
 142         assert(hammer_is_index_record(zone));
 143
 144 again:
 145         assert(blockmap->next_offset != HAMMER_ZONE_ENCODE(zone + 1, 0));
 146
 147         tmp_offset = blockmap->next_offset + bytes - 1;
 148         if ((blockmap->next_offset ^ tmp_offset) & ~HAMMER_BUFMASK64) {
 149                 blockmap->next_offset = tmp_offset & ~HAMMER_BUFMASK64;
 150         }
 151         block_offset = blockmap->next_offset & HAMMER_BIGBLOCK_MASK;
 152
 153         /*
 154          * Dive layer 1.
 155          */
 156         layer1_offset = freemap->phys_offset +
 157                         HAMMER_BLOCKMAP_LAYER1_OFFSET(blockmap->next_offset);
 158         layer1 = get_buffer_data(layer1_offset, &buffer1, 0);
 159         assert(layer1->phys_offset != HAMMER_BLOCKMAP_UNAVAIL);
 160         assert(!(block_offset == 0 && layer1->blocks_free == 0));
 161
 162         /*
 163          * Dive layer 2, each entry represents a big-block.
 164          */
 165         layer2_offset = layer1->phys_offset +
 166                         HAMMER_BLOCKMAP_LAYER2_OFFSET(blockmap->next_offset);
 167         layer2 = get_buffer_data(layer2_offset, &buffer2, 0);
 168
 169         if (layer2->zone == HAMMER_ZONE_UNAVAIL_INDEX)
 170                 errx(1, "alloc_blockmap: layer2 ran out of space!");
 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(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 == block_offset);
 191         layer2->bytes_free -= bytes;
 192         *result_offp = blockmap->next_offset;
 193         blockmap->next_offset += bytes;
 194         layer2->append_off = (int)blockmap->next_offset & HAMMER_BIGBLOCK_MASK;
 195         hammer_crc_set_layer2(layer2);
 196
 197         ptr = get_buffer_data(*result_offp, bufferp, 0);
 198         (*bufferp)->cache.modified = 1;
 199
 200         buffer1->cache.modified = 1;
 201         buffer2->cache.modified = 1;
 202
 203         rel_buffer(buffer1);
 204         rel_buffer(buffer2);
 205         return(ptr);
 206 }
 207
 208 hammer_off_t
 209 blockmap_lookup(hammer_off_t zone_offset, int *errorp)
 210 {
 211         return(blockmap_lookup_save(zone_offset, NULL, NULL, errorp));
 212 }
 213
 214 hammer_off_t
 215 blockmap_lookup_save(hammer_off_t zone_offset,
 216                 hammer_blockmap_layer1_t save_layer1,
 217                 hammer_blockmap_layer2_t save_layer2,
 218                 int *errorp)
 219 {
 220         struct volume_info *root_volume = NULL;
 221         hammer_volume_ondisk_t ondisk;
 222         hammer_blockmap_t blockmap;
 223         hammer_blockmap_t freemap;
 224         hammer_blockmap_layer1_t layer1;
 225         hammer_blockmap_layer2_t layer2;
 226         struct buffer_info *buffer1 = NULL;
 227         struct buffer_info *buffer2 = NULL;
 228         hammer_off_t layer1_offset;
 229         hammer_off_t layer2_offset;
 230         hammer_off_t result_offset = HAMMER_OFF_BAD;;
 231         int zone;
 232         int error = 0;
 233
 234         if (save_layer1)
 235                 bzero(save_layer1, sizeof(*save_layer1));
 236         if (save_layer2)
 237                 bzero(save_layer2, sizeof(*save_layer2));
 238
 239         zone = HAMMER_ZONE_DECODE(zone_offset);
 240
 241         if (zone <= HAMMER_ZONE_RAW_VOLUME_INDEX) {
 242                 error = -1;
 243                 goto done;
 244         }
 245         if (zone >= HAMMER_MAX_ZONES) {
 246                 error = -2;
 247                 goto done;
 248         }
 249
 250         root_volume = get_root_volume();
 251         ondisk = root_volume->ondisk;
 252         blockmap = &ondisk->vol0_blockmap[zone];
 253
 254         /*
 255          * Handle blockmap offset translations.
 256          */
 257         if (hammer_is_index_record(zone)) {
 258                 result_offset = hammer_xlate_to_zone2(zone_offset);
 259         } else if (zone == HAMMER_ZONE_UNDO_INDEX) {
 260                 if (zone_offset >= blockmap->alloc_offset) {
 261                         error = -3;
 262                         goto done;
 263                 }
 264                 result_offset = hammer_xlate_to_undo(ondisk, zone_offset);
 265         } else {
 266                 /* assert(zone == HAMMER_ZONE_RAW_BUFFER_INDEX); */
 267                 result_offset = zone_offset;
 268         }
 269
 270         /*
 271          * The blockmap should match the requested zone (else the volume
 272          * header is mashed).
 273          */
 274         if (hammer_is_index_record(zone) &&
 275             HAMMER_ZONE_DECODE(blockmap->alloc_offset) != zone) {
 276                 error = -4;
 277                 goto done;
 278         }
 279
 280         /*
 281          * Validate that the big-block is assigned to the zone.  Also
 282          * assign save_layer{1,2} if not NULL.
 283          */
 284         freemap = &ondisk->vol0_blockmap[HAMMER_ZONE_FREEMAP_INDEX];
 285
 286         /*
 287          * Dive layer 1.
 288          */
 289         layer1_offset = freemap->phys_offset +
 290                         HAMMER_BLOCKMAP_LAYER1_OFFSET(result_offset);
 291         layer1 = get_buffer_data(layer1_offset, &buffer1, 0);
 292
 293         if (layer1 == NULL) {
 294                 error = -5;
 295                 goto done;
 296         }
 297         if (layer1->phys_offset == HAMMER_BLOCKMAP_UNAVAIL) {
 298                 error = -6;
 299                 goto done;
 300         }
 301         if (save_layer1)
 302                 *save_layer1 = *layer1;
 303
 304         /*
 305          * Dive layer 2, each entry represents a big-block.
 306          */
 307         layer2_offset = layer1->phys_offset +
 308                         HAMMER_BLOCKMAP_LAYER2_OFFSET(result_offset);
 309         layer2 = get_buffer_data(layer2_offset, &buffer2, 0);
 310
 311         if (layer2 == NULL) {
 312                 error = -7;
 313                 goto done;
 314         }
 315         if (layer2->zone != zone) {
 316                 error = -8;
 317                 goto done;
 318         }
 319         if (save_layer2)
 320                 *save_layer2 = *layer2;
 321
 322 done:
 323         rel_buffer(buffer1);
 324         rel_buffer(buffer2);
 325
 326         if (errorp)
 327                 *errorp = error;
 328
 329         return(result_offset);
 330 }
 331