lustre/include/lustre_lmv.h

   1 /*
   2  * GPL HEADER START
   3  *
   4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 only,
   8  * as published by the Free Software Foundation.
   9
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License version 2 for more details.  A copy is
  14  * included in the COPYING file that accompanied this code.
  15
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  19  *
  20  * GPL HEADER END
  21  */
  22 /*
  23  * Copyright (c) 2014, 2016, Intel Corporation.
  24  */
  25 /*
  26  * lustre/include/lustre_lmv.h
  27  *
  28  * Lustre LMV structures and functions.
  29  *
  30  * Author: Di Wang <di.wang@intel.com>
  31  */
  32
  33 #ifndef _LUSTRE_LMV_H
  34 #define _LUSTRE_LMV_H
  35 #include <uapi/linux/lustre/lustre_idl.h>
  36
  37 struct lmv_oinfo {
  38         struct lu_fid   lmo_fid;
  39         u32             lmo_mds;
  40         struct inode    *lmo_root;
  41 };
  42
  43 struct lmv_stripe_md {
  44         __u32   lsm_md_magic;
  45         __u32   lsm_md_stripe_count;
  46         __u32   lsm_md_master_mdt_index;
  47         __u32   lsm_md_hash_type;
  48         __u32   lsm_md_layout_version;
  49         __u32   lsm_md_migrate_offset;
  50         __u32   lsm_md_migrate_hash;
  51         __u32   lsm_md_default_count;
  52         __u32   lsm_md_default_index;
  53         char    lsm_md_pool_name[LOV_MAXPOOLNAME + 1];
  54         struct lmv_oinfo lsm_md_oinfo[0];
  55 };
  56
  57 static inline bool lmv_is_known_hash_type(__u32 type)
  58 {
  59         return (type & LMV_HASH_TYPE_MASK) == LMV_HASH_TYPE_FNV_1A_64 ||
  60                (type & LMV_HASH_TYPE_MASK) == LMV_HASH_TYPE_ALL_CHARS;
  61 }
  62
  63 static inline bool lmv_dir_striped(const struct lmv_stripe_md *lsm)
  64 {
  65         return lsm && lsm->lsm_md_magic == LMV_MAGIC;
  66 }
  67
  68 static inline bool lmv_dir_foreign(const struct lmv_stripe_md *lsm)
  69 {
  70         return lsm && lsm->lsm_md_magic == LMV_MAGIC_FOREIGN;
  71 }
  72
  73 static inline bool lmv_dir_migrating(const struct lmv_stripe_md *lsm)
  74 {
  75         return lmv_dir_striped(lsm) &&
  76                lsm->lsm_md_hash_type & LMV_HASH_FLAG_MIGRATION;
  77 }
  78
  79 static inline bool lmv_dir_bad_hash(const struct lmv_stripe_md *lsm)
  80 {
  81         if (!lmv_dir_striped(lsm))
  82                 return false;
  83
  84         if (lmv_dir_migrating(lsm) &&
  85             lsm->lsm_md_stripe_count - lsm->lsm_md_migrate_offset <= 1)
  86                 return false;
  87
  88         return !lmv_is_known_hash_type(lsm->lsm_md_hash_type);
  89 }
  90
  91 /* NB, this is checking directory default LMV */
  92 static inline bool lmv_dir_qos_mkdir(const struct lmv_stripe_md *lsm)
  93 {
  94         return lsm && (lsm->lsm_md_hash_type & LMV_HASH_FLAG_SPACE);
  95 }
  96
  97 static inline bool
  98 lsm_md_eq(const struct lmv_stripe_md *lsm1, const struct lmv_stripe_md *lsm2)
  99 {
 100         __u32 idx;
 101
 102         if (lsm1->lsm_md_magic != lsm2->lsm_md_magic ||
 103             lsm1->lsm_md_stripe_count != lsm2->lsm_md_stripe_count ||
 104             lsm1->lsm_md_master_mdt_index !=
 105                                 lsm2->lsm_md_master_mdt_index ||
 106             lsm1->lsm_md_hash_type != lsm2->lsm_md_hash_type ||
 107             lsm1->lsm_md_layout_version !=
 108                                 lsm2->lsm_md_layout_version ||
 109             lsm1->lsm_md_migrate_offset !=
 110                                 lsm2->lsm_md_migrate_offset ||
 111             lsm1->lsm_md_migrate_hash !=
 112                                 lsm2->lsm_md_migrate_hash ||
 113             strcmp(lsm1->lsm_md_pool_name,
 114                       lsm2->lsm_md_pool_name) != 0)
 115                 return false;
 116
 117         if (lmv_dir_striped(lsm1)) {
 118                 for (idx = 0; idx < lsm1->lsm_md_stripe_count; idx++) {
 119                         if (!lu_fid_eq(&lsm1->lsm_md_oinfo[idx].lmo_fid,
 120                                        &lsm2->lsm_md_oinfo[idx].lmo_fid))
 121                                 return false;
 122                 }
 123         }
 124
 125         return true;
 126 }
 127
 128 static inline void lsm_md_dump(int mask, const struct lmv_stripe_md *lsm)
 129 {
 130         int i;
 131
 132         CDEBUG(mask, "magic %#x stripe count %d master mdt %d hash type %#x "
 133                 "version %d migrate offset %d migrate hash %#x pool %s\n",
 134                 lsm->lsm_md_magic, lsm->lsm_md_stripe_count,
 135                 lsm->lsm_md_master_mdt_index, lsm->lsm_md_hash_type,
 136                 lsm->lsm_md_layout_version, lsm->lsm_md_migrate_offset,
 137                 lsm->lsm_md_migrate_hash, lsm->lsm_md_pool_name);
 138
 139         if (!lmv_dir_striped(lsm))
 140                 return;
 141
 142         for (i = 0; i < lsm->lsm_md_stripe_count; i++)
 143                 CDEBUG(mask, "stripe[%d] "DFID"\n",
 144                        i, PFID(&lsm->lsm_md_oinfo[i].lmo_fid));
 145 }
 146
 147 union lmv_mds_md;
 148
 149 void lmv_free_memmd(struct lmv_stripe_md *lsm);
 150
 151 static inline void lmv1_le_to_cpu(struct lmv_mds_md_v1 *lmv_dst,
 152                                   const struct lmv_mds_md_v1 *lmv_src)
 153 {
 154         __u32 i;
 155
 156         lmv_dst->lmv_magic = le32_to_cpu(lmv_src->lmv_magic);
 157         lmv_dst->lmv_stripe_count = le32_to_cpu(lmv_src->lmv_stripe_count);
 158         lmv_dst->lmv_master_mdt_index =
 159                                 le32_to_cpu(lmv_src->lmv_master_mdt_index);
 160         lmv_dst->lmv_hash_type = le32_to_cpu(lmv_src->lmv_hash_type);
 161         lmv_dst->lmv_layout_version = le32_to_cpu(lmv_src->lmv_layout_version);
 162         for (i = 0; i < lmv_src->lmv_stripe_count; i++)
 163                 fid_le_to_cpu(&lmv_dst->lmv_stripe_fids[i],
 164                               &lmv_src->lmv_stripe_fids[i]);
 165 }
 166
 167 static inline void lmv_le_to_cpu(union lmv_mds_md *lmv_dst,
 168                                  const union lmv_mds_md *lmv_src)
 169 {
 170         switch (le32_to_cpu(lmv_src->lmv_magic)) {
 171         case LMV_MAGIC_V1:
 172                 lmv1_le_to_cpu(&lmv_dst->lmv_md_v1, &lmv_src->lmv_md_v1);
 173                 break;
 174         default:
 175                 break;
 176         }
 177 }
 178
 179 /* This hash is only for testing purpose */
 180 static inline unsigned int
 181 lmv_hash_all_chars(unsigned int count, const char *name, int namelen)
 182 {
 183         unsigned int c = 0;
 184         const unsigned char *p = (const unsigned char *)name;
 185
 186         while (--namelen >= 0)
 187                 c += p[namelen];
 188
 189         c = c % count;
 190
 191         return c;
 192 }
 193
 194 static inline unsigned int
 195 lmv_hash_fnv1a(unsigned int count, const char *name, int namelen)
 196 {
 197         __u64 hash;
 198
 199         hash = lustre_hash_fnv_1a_64(name, namelen);
 200
 201         return do_div(hash, count);
 202 }
 203
 204 static inline int lmv_name_to_stripe_index(__u32 lmv_hash_type,
 205                                            unsigned int stripe_count,
 206                                            const char *name, int namelen)
 207 {
 208         int idx;
 209
 210         LASSERT(namelen > 0);
 211
 212         if (stripe_count <= 1)
 213                 return 0;
 214
 215         switch (lmv_hash_type & LMV_HASH_TYPE_MASK) {
 216         case LMV_HASH_TYPE_ALL_CHARS:
 217                 idx = lmv_hash_all_chars(stripe_count, name, namelen);
 218                 break;
 219         case LMV_HASH_TYPE_FNV_1A_64:
 220                 idx = lmv_hash_fnv1a(stripe_count, name, namelen);
 221                 break;
 222         default:
 223                 idx = -EBADFD;
 224                 break;
 225         }
 226
 227         CDEBUG(D_INFO, "name %.*s hash_type %#x idx %d/%u\n", namelen, name,
 228                lmv_hash_type, idx, stripe_count);
 229
 230         return idx;
 231 }
 232
 233 static inline bool lmv_magic_supported(__u32 lum_magic)
 234 {
 235         return lum_magic == LMV_USER_MAGIC ||
 236                lum_magic == LMV_USER_MAGIC_SPECIFIC ||
 237                lum_magic == LMV_MAGIC_FOREIGN;
 238 }
 239
 240 #endif