external/gpl2/lvm2/dist/lib/format_pool/disk_rep.c

   1 /*      $NetBSD$        */
   2
   3 /*
   4  * Copyright (C) 1997-2004 Sistina Software, Inc. All rights reserved.
   5  * Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved.
   6  *
   7  * This file is part of LVM2.
   8  *
   9  * This copyrighted material is made available to anyone wishing to use,
  10  * modify, copy, or redistribute it subject to the terms and conditions
  11  * of the GNU Lesser General Public License v.2.1.
  12  *
  13  * You should have received a copy of the GNU Lesser General Public License
  14  * along with this program; if not, write to the Free Software Foundation,
  15  * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  16  */
  17
  18 #include "lib.h"
  19 #include "label.h"
  20 #include "metadata.h"
  21 #include "lvmcache.h"
  22 #include "filter.h"
  23 #include "xlate.h"
  24 #include "disk_rep.h"
  25
  26 #include <assert.h>
  27
  28 /* FIXME: memcpy might not be portable */
  29 #define CPIN_8(x, y, z) {memcpy((x), (y), (z));}
  30 #define CPOUT_8(x, y, z) {memcpy((y), (x), (z));}
  31 #define CPIN_16(x, y) {(x) = xlate16_be((y));}
  32 #define CPOUT_16(x, y) {(y) = xlate16_be((x));}
  33 #define CPIN_32(x, y) {(x) = xlate32_be((y));}
  34 #define CPOUT_32(x, y) {(y) = xlate32_be((x));}
  35 #define CPIN_64(x, y) {(x) = xlate64_be((y));}
  36 #define CPOUT_64(x, y) {(y) = xlate64_be((x));}
  37
  38 static int __read_pool_disk(const struct format_type *fmt, struct device *dev,
  39                             struct dm_pool *mem __attribute((unused)), struct pool_list *pl,
  40                             const char *vg_name __attribute((unused)))
  41 {
  42         char buf[512] __attribute((aligned(8)));
  43
  44         /* FIXME: Need to check the cache here first */
  45         if (!dev_read(dev, UINT64_C(0), 512, buf)) {
  46                 log_very_verbose("Failed to read PV data from %s",
  47                                  dev_name(dev));
  48                 return 0;
  49         }
  50
  51         if (!read_pool_label(pl, fmt->labeller, dev, buf, NULL))
  52                 return_0;
  53
  54         return 1;
  55 }
  56
  57 static void _add_pl_to_list(struct dm_list *head, struct pool_list *data)
  58 {
  59         struct pool_list *pl;
  60
  61         dm_list_iterate_items(pl, head) {
  62                 if (id_equal(&data->pv_uuid, &pl->pv_uuid)) {
  63                         char uuid[ID_LEN + 7] __attribute((aligned(8)));
  64
  65                         id_write_format(&pl->pv_uuid, uuid, ID_LEN + 7);
  66
  67                         if (!dev_subsystem_part_major(data->dev)) {
  68                                 log_very_verbose("Ignoring duplicate PV %s on "
  69                                                  "%s", uuid,
  70                                                  dev_name(data->dev));
  71                                 return;
  72                         }
  73                         log_very_verbose("Duplicate PV %s - using %s %s",
  74                                          uuid, dev_subsystem_name(data->dev),
  75                                          dev_name(data->dev));
  76                         dm_list_del(&pl->list);
  77                         break;
  78                 }
  79         }
  80         dm_list_add(head, &data->list);
  81 }
  82
  83 int read_pool_label(struct pool_list *pl, struct labeller *l,
  84                     struct device *dev, char *buf, struct label **label)
  85 {
  86         struct lvmcache_info *info;
  87         struct id pvid;
  88         struct id vgid;
  89         char uuid[ID_LEN + 7] __attribute((aligned(8)));
  90         struct pool_disk *pd = &pl->pd;
  91
  92         pool_label_in(pd, buf);
  93
  94         get_pool_pv_uuid(&pvid, pd);
  95         id_write_format(&pvid, uuid, ID_LEN + 7);
  96         log_debug("Calculated uuid %s for %s", uuid, dev_name(dev));
  97
  98         get_pool_vg_uuid(&vgid, pd);
  99         id_write_format(&vgid, uuid, ID_LEN + 7);
 100         log_debug("Calculated uuid %s for %s", uuid, pd->pl_pool_name);
 101
 102         if (!(info = lvmcache_add(l, (char *) &pvid, dev, pd->pl_pool_name,
 103                                   (char *) &vgid, 0)))
 104                 return_0;
 105         if (label)
 106                 *label = info->label;
 107
 108         info->device_size = xlate32_be(pd->pl_blocks) << SECTOR_SHIFT;
 109         dm_list_init(&info->mdas);
 110
 111         info->status &= ~CACHE_INVALID;
 112
 113         pl->dev = dev;
 114         pl->pv = NULL;
 115         memcpy(&pl->pv_uuid, &pvid, sizeof(pvid));
 116
 117         return 1;
 118 }
 119
 120 /**
 121  * pool_label_out - copies a pool_label_t into a char buffer
 122  * @pl: ptr to a pool_label_t struct
 123  * @buf: ptr to raw space where label info will be copied
 124  *
 125  * This function is important because it takes care of all of
 126  * the endian issues when copying to disk.  This way, when
 127  * machines of different architectures are used, they will
 128  * be able to interpret ondisk labels correctly.  Always use
 129  * this function before writing to disk.
 130  */
 131 void pool_label_out(struct pool_disk *pl, void *buf)
 132 {
 133         struct pool_disk *bufpl = (struct pool_disk *) buf;
 134
 135         CPOUT_64(pl->pl_magic, bufpl->pl_magic);
 136         CPOUT_64(pl->pl_pool_id, bufpl->pl_pool_id);
 137         CPOUT_8(pl->pl_pool_name, bufpl->pl_pool_name, POOL_NAME_SIZE);
 138         CPOUT_32(pl->pl_version, bufpl->pl_version);
 139         CPOUT_32(pl->pl_subpools, bufpl->pl_subpools);
 140         CPOUT_32(pl->pl_sp_id, bufpl->pl_sp_id);
 141         CPOUT_32(pl->pl_sp_devs, bufpl->pl_sp_devs);
 142         CPOUT_32(pl->pl_sp_devid, bufpl->pl_sp_devid);
 143         CPOUT_32(pl->pl_sp_type, bufpl->pl_sp_type);
 144         CPOUT_64(pl->pl_blocks, bufpl->pl_blocks);
 145         CPOUT_32(pl->pl_striping, bufpl->pl_striping);
 146         CPOUT_32(pl->pl_sp_dmepdevs, bufpl->pl_sp_dmepdevs);
 147         CPOUT_32(pl->pl_sp_dmepid, bufpl->pl_sp_dmepid);
 148         CPOUT_32(pl->pl_sp_weight, bufpl->pl_sp_weight);
 149         CPOUT_32(pl->pl_minor, bufpl->pl_minor);
 150         CPOUT_32(pl->pl_padding, bufpl->pl_padding);
 151         CPOUT_8(pl->pl_reserve, bufpl->pl_reserve, 184);
 152 }
 153
 154 /**
 155  * pool_label_in - copies a char buffer into a pool_label_t
 156  * @pl: ptr to a pool_label_t struct
 157  * @buf: ptr to raw space where label info is copied from
 158  *
 159  * This function is important because it takes care of all of
 160  * the endian issues when information from disk is about to be
 161  * used.  This way, when machines of different architectures
 162  * are used, they will be able to interpret ondisk labels
 163  * correctly.  Always use this function before using labels that
 164  * were read from disk.
 165  */
 166 void pool_label_in(struct pool_disk *pl, void *buf)
 167 {
 168         struct pool_disk *bufpl = (struct pool_disk *) buf;
 169
 170         CPIN_64(pl->pl_magic, bufpl->pl_magic);
 171         CPIN_64(pl->pl_pool_id, bufpl->pl_pool_id);
 172         CPIN_8(pl->pl_pool_name, bufpl->pl_pool_name, POOL_NAME_SIZE);
 173         CPIN_32(pl->pl_version, bufpl->pl_version);
 174         CPIN_32(pl->pl_subpools, bufpl->pl_subpools);
 175         CPIN_32(pl->pl_sp_id, bufpl->pl_sp_id);
 176         CPIN_32(pl->pl_sp_devs, bufpl->pl_sp_devs);
 177         CPIN_32(pl->pl_sp_devid, bufpl->pl_sp_devid);
 178         CPIN_32(pl->pl_sp_type, bufpl->pl_sp_type);
 179         CPIN_64(pl->pl_blocks, bufpl->pl_blocks);
 180         CPIN_32(pl->pl_striping, bufpl->pl_striping);
 181         CPIN_32(pl->pl_sp_dmepdevs, bufpl->pl_sp_dmepdevs);
 182         CPIN_32(pl->pl_sp_dmepid, bufpl->pl_sp_dmepid);
 183         CPIN_32(pl->pl_sp_weight, bufpl->pl_sp_weight);
 184         CPIN_32(pl->pl_minor, bufpl->pl_minor);
 185         CPIN_32(pl->pl_padding, bufpl->pl_padding);
 186         CPIN_8(pl->pl_reserve, bufpl->pl_reserve, 184);
 187 }
 188
 189 static char _calc_char(unsigned int id)
 190 {
 191         /*
 192          * [0-9A-Za-z!#] - 64 printable chars (6-bits)
 193          */
 194
 195         if (id < 10)
 196                 return id + 48;
 197         if (id < 36)
 198                 return (id - 10) + 65;
 199         if (id < 62)
 200                 return (id - 36) + 97;
 201         if (id == 62)
 202                 return '!';
 203         if (id == 63)
 204                 return '#';
 205
 206         return '%';
 207 }
 208
 209 void get_pool_uuid(char *uuid, uint64_t poolid, uint32_t spid, uint32_t devid)
 210 {
 211         int i;
 212         unsigned shifter = 0x003F;
 213
 214         assert(ID_LEN == 32);
 215         memset(uuid, 0, ID_LEN);
 216         strcat(uuid, "POOL0000000000");
 217
 218         /* We grab the entire 64 bits (+2 that get shifted in) */
 219         for (i = 13; i < 24; i++) {
 220                 uuid[i] = _calc_char(((unsigned) poolid) & shifter);
 221                 poolid = poolid >> 6;
 222         }
 223
 224         /* We grab the entire 32 bits (+4 that get shifted in) */
 225         for (i = 24; i < 30; i++) {
 226                 uuid[i] = _calc_char((unsigned) (spid & shifter));
 227                 spid = spid >> 6;
 228         }
 229
 230         /*
 231          * Since we can only have 128 devices, we only worry about the
 232          * last 12 bits
 233          */
 234         for (i = 30; i < 32; i++) {
 235                 uuid[i] = _calc_char((unsigned) (devid & shifter));
 236                 devid = devid >> 6;
 237         }
 238
 239 }
 240
 241 static int _read_vg_pds(const struct format_type *fmt, struct dm_pool *mem,
 242                         struct lvmcache_vginfo *vginfo, struct dm_list *head,
 243                         uint32_t *devcount)
 244 {
 245         struct lvmcache_info *info;
 246         struct pool_list *pl = NULL;
 247         struct dm_pool *tmpmem;
 248
 249         uint32_t sp_count = 0;
 250         uint32_t *sp_devs = NULL;
 251         uint32_t i;
 252
 253         /* FIXME: maybe should return a different error in memory
 254          * allocation failure */
 255         if (!(tmpmem = dm_pool_create("pool read_vg", 512)))
 256                 return_0;
 257
 258         dm_list_iterate_items(info, &vginfo->infos) {
 259                 if (info->dev &&
 260                     !(pl = read_pool_disk(fmt, info->dev, mem, vginfo->vgname)))
 261                             break;
 262                 /*
 263                  * We need to keep track of the total expected number
 264                  * of devices per subpool
 265                  */
 266                 if (!sp_count) {
 267                         /* FIXME pl left uninitialised if !info->dev */
 268                         sp_count = pl->pd.pl_subpools;
 269                         if (!(sp_devs =
 270                               dm_pool_zalloc(tmpmem,
 271                                           sizeof(uint32_t) * sp_count))) {
 272                                 log_error("Unable to allocate %d 32-bit uints",
 273                                           sp_count);
 274                                 dm_pool_destroy(tmpmem);
 275                                 return 0;
 276                         }
 277                 }
 278                 /*
 279                  * watch out for a pool label with a different subpool
 280                  * count than the original - give up if it does
 281                  */
 282                 if (sp_count != pl->pd.pl_subpools)
 283                         break;
 284
 285                 _add_pl_to_list(head, pl);
 286
 287                 if (sp_count > pl->pd.pl_sp_id && sp_devs[pl->pd.pl_sp_id] == 0)
 288                         sp_devs[pl->pd.pl_sp_id] = pl->pd.pl_sp_devs;
 289         }
 290
 291         *devcount = 0;
 292         for (i = 0; i < sp_count; i++)
 293                 *devcount += sp_devs[i];
 294
 295         dm_pool_destroy(tmpmem);
 296
 297         if (pl && *pl->pd.pl_pool_name)
 298                 return 1;
 299
 300         return 0;
 301
 302 }
 303
 304 int read_pool_pds(const struct format_type *fmt, const char *vg_name,
 305                   struct dm_pool *mem, struct dm_list *pdhead)
 306 {
 307         struct lvmcache_vginfo *vginfo;
 308         uint32_t totaldevs;
 309         int full_scan = -1;
 310
 311         do {
 312                 /*
 313                  * If the cache scanning doesn't work, this will never work
 314                  */
 315                 if (vg_name && (vginfo = vginfo_from_vgname(vg_name, NULL)) &&
 316                     vginfo->infos.n) {
 317
 318                         if (_read_vg_pds(fmt, mem, vginfo, pdhead, &totaldevs)) {
 319                                 /*
 320                                  * If we found all the devices we were
 321                                  * expecting, return success
 322                                  */
 323                                 if (dm_list_size(pdhead) == totaldevs)
 324                                         return 1;
 325
 326                                 /*
 327                                  * accept partial pool if we've done a full
 328                                  * rescan of the cache
 329                                  */
 330                                 if (full_scan > 0)
 331                                         return 1;
 332                         }
 333                 }
 334                 /* Failed */
 335                 dm_list_init(pdhead);
 336
 337                 full_scan++;
 338                 if (full_scan > 1) {
 339                         log_debug("No devices for vg %s found in cache",
 340                                   vg_name);
 341                         return 0;
 342                 }
 343                 lvmcache_label_scan(fmt->cmd, full_scan);
 344
 345         } while (1);
 346
 347 }
 348
 349 struct pool_list *read_pool_disk(const struct format_type *fmt,
 350                                  struct device *dev, struct dm_pool *mem,
 351                                  const char *vg_name)
 352 {
 353         struct pool_list *pl;
 354
 355         if (!dev_open(dev))
 356                 return_NULL;
 357
 358         if (!(pl = dm_pool_zalloc(mem, sizeof(*pl)))) {
 359                 log_error("Unable to allocate pool list structure");
 360                 return 0;
 361         }
 362
 363         if (!__read_pool_disk(fmt, dev, mem, pl, vg_name))
 364                 return_NULL;
 365
 366         if (!dev_close(dev))
 367                 stack;
 368
 369         return pl;
 370
 371 }