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(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                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         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
 170         /*
 171          * If we are entering a new big-block assign ownership to our
 172          * zone.  If the big-block is owned by another zone skip it.
 173          */
 174         if (layer2->zone == 0) {
 175                 --layer1->blocks_free;
 176                 hammer_crc_set_layer1(HammerVersion, layer1);
 177                 layer2->zone = zone;
 178                 --volume->ondisk->vol0_stat_freebigblocks;
 179                 assert(layer2->bytes_free == HAMMER_BIGBLOCK_SIZE);
 180                 assert(layer2->append_off == 0);
 181         }
 182         if (layer2->zone != zone) {
 183                 blockmap->next_offset =
 184                         HAMMER_ZONE_LAYER2_NEXT_OFFSET(blockmap->next_offset);
 185                 goto again;
 186         }
 187
 188         assert(layer2->append_off ==
 189                 (blockmap->next_offset & HAMMER_BIGBLOCK_MASK));
 190         layer2->bytes_free -= bytes;
 191         *result_offp = blockmap->next_offset;
 192         blockmap->next_offset += bytes;
 193         layer2->append_off = (int)blockmap->next_offset & HAMMER_BIGBLOCK_MASK;
 194         hammer_crc_set_layer2(HammerVersion, layer2);
 195
 196         ptr = get_buffer_data(*result_offp, bufferp, 0);
 197         (*bufferp)->cache.modified = 1;
 198
 199         buffer1->cache.modified = 1;
 200         buffer2->cache.modified = 1;
 201
 202         rel_buffer(buffer1);
 203         rel_buffer(buffer2);
 204         return(ptr);
 205 }
 206
 207 hammer_off_t
 208 blockmap_lookup(hammer_off_t zone_offset, int *errorp)
 209 {
 210         return(blockmap_lookup_save(zone_offset, NULL, NULL, errorp));
 211 }
 212
 213 hammer_off_t
 214 blockmap_lookup_save(hammer_off_t zone_offset,
 215                 hammer_blockmap_layer1_t save_layer1,
 216                 hammer_blockmap_layer2_t save_layer2,
 217                 int *errorp)
 218 {
 219         struct volume_info *root_volume = NULL;
 220         hammer_volume_ondisk_t ondisk;
 221         hammer_blockmap_t blockmap;
 222         hammer_blockmap_t freemap;
 223         hammer_blockmap_layer1_t layer1;
 224         hammer_blockmap_layer2_t layer2;
 225         struct buffer_info *buffer1 = NULL;
 226         struct buffer_info *buffer2 = NULL;
 227         hammer_off_t layer1_offset;
 228         hammer_off_t layer2_offset;
 229         hammer_off_t result_offset = HAMMER_OFF_BAD;;
 230         int zone;
 231         int error = 0;
 232
 233         if (save_layer1)
 234                 bzero(save_layer1, sizeof(*save_layer1));
 235         if (save_layer2)
 236                 bzero(save_layer2, sizeof(*save_layer2));
 237
 238         zone = HAMMER_ZONE_DECODE(zone_offset);
 239
 240         if (zone <= HAMMER_ZONE_RAW_VOLUME_INDEX) {
 241                 error = -1;
 242                 goto done;
 243         }
 244         if (zone >= HAMMER_MAX_ZONES) {
 245                 error = -2;
 246                 goto done;
 247         }
 248
 249         root_volume = get_root_volume();
 250         ondisk = root_volume->ondisk;
 251         blockmap = &ondisk->vol0_blockmap[zone];
 252
 253         /*
 254          * Handle blockmap offset translations.
 255          */
 256         if (hammer_is_index_record(zone)) {
 257                 result_offset = hammer_xlate_to_zone2(zone_offset);
 258         } else if (zone == HAMMER_ZONE_UNDO_INDEX) {
 259                 if (zone_offset >= blockmap->alloc_offset) {
 260                         error = -3;
 261                         goto done;
 262                 }
 263                 result_offset = hammer_xlate_to_undo(ondisk, zone_offset);
 264         } else {
 265                 /* assert(zone == HAMMER_ZONE_RAW_BUFFER_INDEX); */
 266                 result_offset = zone_offset;
 267         }
 268
 269         /*
 270          * The blockmap should match the requested zone (else the volume
 271          * header is mashed).
 272          */
 273         if (hammer_is_index_record(zone) &&
 274             HAMMER_ZONE_DECODE(blockmap->alloc_offset) != zone) {
 275                 error = -4;
 276                 goto done;
 277         }
 278
 279         /*
 280          * Validate that the big-block is assigned to the zone.  Also
 281          * assign save_layer{1,2} if not NULL.
 282          */
 283         freemap = &ondisk->vol0_blockmap[HAMMER_ZONE_FREEMAP_INDEX];
 284
 285         /*
 286          * Dive layer 1.
 287          */
 288         layer1_offset = freemap->phys_offset +
 289                         HAMMER_BLOCKMAP_LAYER1_OFFSET(result_offset);
 290         layer1 = get_buffer_data(layer1_offset, &buffer1, 0);
 291
 292         if (layer1 == NULL) {
 293                 error = -5;
 294                 goto done;
 295         }
 296         if (layer1->phys_offset == HAMMER_BLOCKMAP_UNAVAIL) {
 297                 error = -6;
 298                 goto done;
 299         }
 300         if (save_layer1)
 301                 *save_layer1 = *layer1;
 302
 303         /*
 304          * Dive layer 2, each entry represents a big-block.
 305          */
 306         layer2_offset = layer1->phys_offset +
 307                         HAMMER_BLOCKMAP_LAYER2_OFFSET(result_offset);
 308         layer2 = get_buffer_data(layer2_offset, &buffer2, 0);
 309
 310         if (layer2 == NULL) {
 311                 error = -7;
 312                 goto done;
 313         }
 314         if (layer2->zone != zone) {
 315                 error = -8;
 316                 goto done;
 317         }
 318         if (save_layer2)
 319                 *save_layer2 = *layer2;
 320
 321 done:
 322         rel_buffer(buffer1);
 323         rel_buffer(buffer2);
 324
 325         if (errorp)
 326                 *errorp = error;
 327
 328         return(result_offset);
 329 }
 330