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  *
  42  * If the zone is HAMMER_ZONE_FREEMAP_INDEX we are bootstrapping the freemap
  43  * itself and cannot update it yet.
  44  */
  45 hammer_off_t
  46 alloc_bigblock(struct volume_info *volume, int zone)
  47 {
  48         struct volume_info *root_vol;
  49         hammer_blockmap_t freemap;
  50         struct buffer_info *buffer1 = NULL;
  51         struct buffer_info *buffer2 = NULL;
  52         hammer_blockmap_layer1_t layer1;
  53         hammer_blockmap_layer2_t layer2;
  54         hammer_off_t layer1_offset;
  55         hammer_off_t layer2_offset;
  56         hammer_off_t result_offset;
  57
  58         assert_volume_offset(volume);
  59         result_offset = volume->vol_free_off;
  60         if (result_offset >= volume->vol_free_end)
  61                 errx(1, "alloc_bigblock: Ran out of room, filesystem too small");
  62
  63         volume->vol_free_off += HAMMER_BIGBLOCK_SIZE;
  64
  65         /*
  66          * Update the freemap if not zone4.
  67          */
  68         if (zone != HAMMER_ZONE_FREEMAP_INDEX) {
  69                 root_vol = get_root_volume();
  70                 freemap = &root_vol->ondisk->vol0_blockmap[HAMMER_ZONE_FREEMAP_INDEX];
  71
  72                 layer1_offset = freemap->phys_offset +
  73                                 HAMMER_BLOCKMAP_LAYER1_OFFSET(result_offset);
  74                 layer1 = get_buffer_data(layer1_offset, &buffer1, 0);
  75                 assert(layer1->phys_offset != HAMMER_BLOCKMAP_UNAVAIL);
  76                 --layer1->blocks_free;
  77                 hammer_crc_set_layer1(layer1);
  78                 buffer1->cache.modified = 1;
  79
  80                 layer2_offset = layer1->phys_offset +
  81                                 HAMMER_BLOCKMAP_LAYER2_OFFSET(result_offset);
  82                 layer2 = get_buffer_data(layer2_offset, &buffer2, 0);
  83                 assert(layer2->zone == 0);
  84                 layer2->zone = zone;
  85                 layer2->append_off = HAMMER_BIGBLOCK_SIZE;
  86                 layer2->bytes_free = 0;
  87                 hammer_crc_set_layer2(layer2);
  88                 buffer2->cache.modified = 1;
  89
  90                 --root_vol->ondisk->vol0_stat_freebigblocks;
  91
  92                 rel_buffer(buffer1);
  93                 rel_buffer(buffer2);
  94         }
  95
  96         return(result_offset);
  97 }
  98
  99 /*
 100  * Allocate a chunk of data out of a blockmap.  This is a simplified
 101  * version which uses next_offset as a simple allocation iterator.
 102  */
 103 void *
 104 alloc_blockmap(int zone, int bytes, hammer_off_t *result_offp,
 105                struct buffer_info **bufferp)
 106 {
 107         struct volume_info *volume;
 108         hammer_blockmap_t blockmap;
 109         hammer_blockmap_t freemap;
 110         struct buffer_info *buffer1 = NULL;
 111         struct buffer_info *buffer2 = NULL;
 112         hammer_blockmap_layer1_t layer1;
 113         hammer_blockmap_layer2_t layer2;
 114         hammer_off_t layer1_offset;
 115         hammer_off_t layer2_offset;
 116         hammer_off_t chunk_offset;
 117         void *ptr;
 118
 119         volume = get_root_volume();
 120
 121         blockmap = &volume->ondisk->vol0_blockmap[zone];
 122         freemap = &volume->ondisk->vol0_blockmap[HAMMER_ZONE_FREEMAP_INDEX];
 123         assert(HAMMER_ZONE_DECODE(blockmap->next_offset) == zone);
 124
 125         /*
 126          * Alignment and buffer-boundary issues.  If the allocation would
 127          * cross a buffer boundary we have to skip to the next buffer.
 128          */
 129         bytes = (bytes + 15) & ~15;
 130         assert(bytes > 0 && bytes <= HAMMER_BUFSIZE);  /* not HAMMER_XBUFSIZE */
 131         assert(hammer_is_zone2_mapped_index(zone));
 132
 133 again:
 134         assert(blockmap->next_offset != HAMMER_ZONE_ENCODE(zone + 1, 0));
 135
 136         if ((blockmap->next_offset ^ (blockmap->next_offset + bytes - 1)) &
 137             ~HAMMER_BUFMASK64) {
 138                 blockmap->next_offset = (blockmap->next_offset + bytes - 1) &
 139                                         ~HAMMER_BUFMASK64;
 140         }
 141         chunk_offset = blockmap->next_offset & HAMMER_BIGBLOCK_MASK;
 142
 143         /*
 144          * Dive layer 1.
 145          */
 146         layer1_offset = freemap->phys_offset +
 147                         HAMMER_BLOCKMAP_LAYER1_OFFSET(blockmap->next_offset);
 148         layer1 = get_buffer_data(layer1_offset, &buffer1, 0);
 149         assert(!(chunk_offset == 0 && layer1->blocks_free == 0));
 150
 151         if (layer1->phys_offset == HAMMER_BLOCKMAP_UNAVAIL) {
 152                 fprintf(stderr, "alloc_blockmap: ran out of space!\n");
 153                 exit(1);
 154         }
 155
 156         /*
 157          * Dive layer 2, each entry represents a big-block.
 158          */
 159         layer2_offset = layer1->phys_offset +
 160                         HAMMER_BLOCKMAP_LAYER2_OFFSET(blockmap->next_offset);
 161         layer2 = get_buffer_data(layer2_offset, &buffer2, 0);
 162
 163         if (layer2->zone == HAMMER_ZONE_UNAVAIL_INDEX) {
 164                 fprintf(stderr, "alloc_blockmap: ran out of space!\n");
 165                 exit(1);
 166         }
 167
 168         /*
 169          * If we are entering a new big-block assign ownership to our
 170          * zone.  If the big-block is owned by another zone skip it.
 171          */
 172         if (layer2->zone == 0) {
 173                 --layer1->blocks_free;
 174                 hammer_crc_set_layer1(layer1);
 175                 layer2->zone = zone;
 176                 --volume->ondisk->vol0_stat_freebigblocks;
 177                 assert(layer2->bytes_free == HAMMER_BIGBLOCK_SIZE);
 178                 assert(layer2->append_off == 0);
 179         }
 180         if (layer2->zone != zone) {
 181                 blockmap->next_offset = (blockmap->next_offset + HAMMER_BIGBLOCK_SIZE) &
 182                                         ~HAMMER_BIGBLOCK_MASK64;
 183                 goto again;
 184         }
 185
 186         assert(layer2->append_off == chunk_offset);
 187         layer2->bytes_free -= bytes;
 188         *result_offp = blockmap->next_offset;
 189         blockmap->next_offset += bytes;
 190         layer2->append_off = (int)blockmap->next_offset & HAMMER_BIGBLOCK_MASK;
 191         hammer_crc_set_layer2(layer2);
 192
 193         ptr = get_buffer_data(*result_offp, bufferp, 0);
 194         (*bufferp)->cache.modified = 1;
 195
 196         buffer1->cache.modified = 1;
 197         buffer2->cache.modified = 1;
 198
 199         rel_buffer(buffer1);
 200         rel_buffer(buffer2);
 201         return(ptr);
 202 }
 203
 204 hammer_off_t
 205 blockmap_lookup(hammer_off_t zone_offset,
 206                 hammer_blockmap_layer1_t save_layer1,
 207                 hammer_blockmap_layer2_t save_layer2,
 208                 int *errorp)
 209 {
 210         struct volume_info *root_volume = NULL;
 211         hammer_blockmap_t blockmap;
 212         hammer_blockmap_t freemap;
 213         hammer_blockmap_layer1_t layer1;
 214         hammer_blockmap_layer2_t layer2;
 215         struct buffer_info *buffer1 = NULL;
 216         struct buffer_info *buffer2 = NULL;
 217         hammer_off_t layer1_offset;
 218         hammer_off_t layer2_offset;
 219         hammer_off_t result_offset;
 220         int zone;
 221         int i;
 222         int error = 0;
 223
 224         if (save_layer1)
 225                 bzero(save_layer1, sizeof(*save_layer1));
 226         if (save_layer2)
 227                 bzero(save_layer2, sizeof(*save_layer2));
 228
 229         zone = HAMMER_ZONE_DECODE(zone_offset);
 230
 231         if (zone <= HAMMER_ZONE_RAW_VOLUME_INDEX)
 232                 error = -1;
 233         if (zone >= HAMMER_MAX_ZONES)
 234                 error = -2;
 235         if (error) {
 236                 result_offset = HAMMER_OFF_BAD;
 237                 goto done;
 238         }
 239
 240         root_volume = get_root_volume();
 241         blockmap = &root_volume->ondisk->vol0_blockmap[zone];
 242
 243         if (zone == HAMMER_ZONE_RAW_BUFFER_INDEX) {
 244                 result_offset = zone_offset;
 245         } else if (zone == HAMMER_ZONE_UNDO_INDEX) {
 246                 i = (zone_offset & HAMMER_OFF_SHORT_MASK) /
 247                     HAMMER_BIGBLOCK_SIZE;
 248                 if (zone_offset >= blockmap->alloc_offset) {
 249                         error = -3;
 250                         result_offset = HAMMER_OFF_BAD;
 251                         goto done;
 252                 }
 253                 result_offset = root_volume->ondisk->vol0_undo_array[i] +
 254                                 (zone_offset & HAMMER_BIGBLOCK_MASK64);
 255         } else {
 256                 result_offset = hammer_xlate_to_zone2(zone_offset);
 257         }
 258
 259         /*
 260          * The blockmap should match the requested zone (else the volume
 261          * header is mashed).
 262          */
 263         if (HAMMER_ZONE_FREEMAP_INDEX != zone &&
 264             HAMMER_ZONE_DECODE(blockmap->alloc_offset) != zone) {
 265                 error = -4;
 266                 goto done;
 267         }
 268
 269         /*
 270          * Validate that the big-block is assigned to the zone.  Also
 271          * assign save_layer{1,2}.
 272          */
 273
 274         freemap = &root_volume->ondisk->vol0_blockmap[HAMMER_ZONE_FREEMAP_INDEX];
 275         /*
 276          * Dive layer 1.
 277          */
 278         layer1_offset = freemap->phys_offset +
 279                         HAMMER_BLOCKMAP_LAYER1_OFFSET(result_offset);
 280         layer1 = get_buffer_data(layer1_offset, &buffer1, 0);
 281         if (layer1 == NULL) {
 282                 error = -5;
 283                 goto done;
 284         }
 285         if (layer1->phys_offset == HAMMER_BLOCKMAP_UNAVAIL) {
 286                 error = -6;
 287                 goto done;
 288         }
 289
 290         if (save_layer1)
 291                 *save_layer1 = *layer1;
 292
 293         /*
 294          * Dive layer 2, each entry represents a big-block.
 295          */
 296         layer2_offset = layer1->phys_offset +
 297                         HAMMER_BLOCKMAP_LAYER2_OFFSET(result_offset);
 298         layer2 = get_buffer_data(layer2_offset, &buffer2, 0);
 299
 300         if (layer2 == NULL) {
 301                 error = -7;
 302                 goto done;
 303         }
 304         if (layer2->zone != zone) {
 305                 error = -8;
 306                 goto done;
 307         }
 308         if (save_layer2)
 309                 *save_layer2 = *layer2;
 310
 311 done:
 312         rel_buffer(buffer1);
 313         rel_buffer(buffer2);
 314
 315         if (errorp)
 316                 *errorp = error;
 317
 318         return(result_offset);
 319 }
 320