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
  58 lsm_md_eq(const struct lmv_stripe_md *lsm1, const struct lmv_stripe_md *lsm2)
  59 {
  60         __u32 idx;
  61
  62         if (lsm1->lsm_md_magic != lsm2->lsm_md_magic ||
  63             lsm1->lsm_md_stripe_count != lsm2->lsm_md_stripe_count ||
  64             lsm1->lsm_md_master_mdt_index !=
  65                                 lsm2->lsm_md_master_mdt_index ||
  66             lsm1->lsm_md_hash_type != lsm2->lsm_md_hash_type ||
  67             lsm1->lsm_md_layout_version !=
  68                                 lsm2->lsm_md_layout_version ||
  69             lsm1->lsm_md_migrate_offset !=
  70                                 lsm2->lsm_md_migrate_offset ||
  71             lsm1->lsm_md_migrate_hash !=
  72                                 lsm2->lsm_md_migrate_hash ||
  73             strcmp(lsm1->lsm_md_pool_name,
  74                       lsm2->lsm_md_pool_name) != 0)
  75                 return false;
  76
  77         for (idx = 0; idx < lsm1->lsm_md_stripe_count; idx++) {
  78                 if (!lu_fid_eq(&lsm1->lsm_md_oinfo[idx].lmo_fid,
  79                                &lsm2->lsm_md_oinfo[idx].lmo_fid))
  80                         return false;
  81         }
  82
  83         return true;
  84 }
  85
  86 static inline void lsm_md_dump(int mask, const struct lmv_stripe_md *lsm)
  87 {
  88         int i;
  89
  90         CDEBUG(mask, "magic %#x stripe count %d master mdt %d hash type %#x "
  91                 "version %d migrate offset %d migrate hash %#x pool %s\n",
  92                 lsm->lsm_md_magic, lsm->lsm_md_stripe_count,
  93                 lsm->lsm_md_master_mdt_index, lsm->lsm_md_hash_type,
  94                 lsm->lsm_md_layout_version, lsm->lsm_md_migrate_offset,
  95                 lsm->lsm_md_migrate_hash, lsm->lsm_md_pool_name);
  96
  97         for (i = 0; i < lsm->lsm_md_stripe_count; i++)
  98                 CDEBUG(mask, "stripe[%d] "DFID"\n",
  99                        i, PFID(&lsm->lsm_md_oinfo[i].lmo_fid));
 100 }
 101
 102 union lmv_mds_md;
 103
 104 void lmv_free_memmd(struct lmv_stripe_md *lsm);
 105
 106 static inline void lmv1_le_to_cpu(struct lmv_mds_md_v1 *lmv_dst,
 107                                   const struct lmv_mds_md_v1 *lmv_src)
 108 {
 109         __u32 i;
 110
 111         lmv_dst->lmv_magic = le32_to_cpu(lmv_src->lmv_magic);
 112         lmv_dst->lmv_stripe_count = le32_to_cpu(lmv_src->lmv_stripe_count);
 113         lmv_dst->lmv_master_mdt_index =
 114                                 le32_to_cpu(lmv_src->lmv_master_mdt_index);
 115         lmv_dst->lmv_hash_type = le32_to_cpu(lmv_src->lmv_hash_type);
 116         lmv_dst->lmv_layout_version = le32_to_cpu(lmv_src->lmv_layout_version);
 117         for (i = 0; i < lmv_src->lmv_stripe_count; i++)
 118                 fid_le_to_cpu(&lmv_dst->lmv_stripe_fids[i],
 119                               &lmv_src->lmv_stripe_fids[i]);
 120 }
 121
 122 static inline void lmv_le_to_cpu(union lmv_mds_md *lmv_dst,
 123                                  const union lmv_mds_md *lmv_src)
 124 {
 125         switch (le32_to_cpu(lmv_src->lmv_magic)) {
 126         case LMV_MAGIC_V1:
 127                 lmv1_le_to_cpu(&lmv_dst->lmv_md_v1, &lmv_src->lmv_md_v1);
 128                 break;
 129         default:
 130                 break;
 131         }
 132 }
 133
 134 /* This hash is only for testing purpose */
 135 static inline unsigned int
 136 lmv_hash_all_chars(unsigned int count, const char *name, int namelen)
 137 {
 138         unsigned int c = 0;
 139         const unsigned char *p = (const unsigned char *)name;
 140
 141         while (--namelen >= 0)
 142                 c += p[namelen];
 143
 144         c = c % count;
 145
 146         return c;
 147 }
 148
 149 static inline unsigned int
 150 lmv_hash_fnv1a(unsigned int count, const char *name, int namelen)
 151 {
 152         __u64 hash;
 153
 154         hash = lustre_hash_fnv_1a_64(name, namelen);
 155
 156         return do_div(hash, count);
 157 }
 158
 159 static inline int lmv_name_to_stripe_index(__u32 lmv_hash_type,
 160                                            unsigned int stripe_count,
 161                                            const char *name, int namelen)
 162 {
 163         int idx;
 164
 165         LASSERT(namelen > 0);
 166
 167         if (stripe_count <= 1)
 168                 return 0;
 169
 170         switch (lmv_hash_type & LMV_HASH_TYPE_MASK) {
 171         case LMV_HASH_TYPE_ALL_CHARS:
 172                 idx = lmv_hash_all_chars(stripe_count, name, namelen);
 173                 break;
 174         case LMV_HASH_TYPE_FNV_1A_64:
 175                 idx = lmv_hash_fnv1a(stripe_count, name, namelen);
 176                 break;
 177         default:
 178                 idx = -EBADFD;
 179                 break;
 180         }
 181
 182         CDEBUG(D_INFO, "name %.*s hash_type %#x idx %d/%u\n", namelen, name,
 183                lmv_hash_type, idx, stripe_count);
 184
 185         return idx;
 186 }
 187
 188 static inline bool lmv_is_known_hash_type(__u32 type)
 189 {
 190         return (type & LMV_HASH_TYPE_MASK) == LMV_HASH_TYPE_FNV_1A_64 ||
 191                (type & LMV_HASH_TYPE_MASK) == LMV_HASH_TYPE_ALL_CHARS;
 192 }
 193
 194 static inline bool lmv_magic_supported(__u32 lum_magic)
 195 {
 196         return lum_magic == LMV_USER_MAGIC ||
 197                lum_magic == LMV_USER_MAGIC_SPECIFIC ||
 198                lum_magic == LMV_MAGIC_FOREIGN;
 199 }
 200
 201 #endif