lustre/lov/lov_pack.c

   1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
   2  * vim:expandtab:shiftwidth=8:tabstop=8:
   3  *
   4  *  Copyright (C) 2002 Cluster File Systems, Inc. <adilger@clusterfs.com>
   5  *
   6  *   This file is part of Lustre, http://www.lustre.org.
   7  *
   8  *   Lustre is free software; you can redistribute it and/or
   9  *   modify it under the terms of version 2 of the GNU General Public
  10  *   License as published by the Free Software Foundation.
  11  *
  12  *   Lustre is distributed in the hope that it will be useful,
  13  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  *   GNU General Public License for more details.
  16  *
  17  *   You should have received a copy of the GNU General Public License
  18  *   along with Lustre; if not, write to the Free Software
  19  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20  *
  21  * (Un)packing of OST/MDS requests
  22  *
  23  */
  24
  25 #define DEBUG_SUBSYSTEM S_LLITE
  26
  27 #include <linux/lustre_net.h>
  28 #include <linux/obd.h>
  29 #include <linux/obd_lov.h>
  30 #include <linux/obd_support.h>
  31
  32 /* lov_packdesc() is in mds/mds_lov.c */
  33
  34 void lov_unpackdesc(struct lov_desc *ld)
  35 {
  36         ld->ld_tgt_count = NTOH__u32(ld->ld_tgt_count);
  37         ld->ld_default_stripe_count = HTON__u32(ld->ld_default_stripe_count);
  38         ld->ld_default_stripe_size = HTON__u32(ld->ld_default_stripe_size);
  39         ld->ld_pattern = HTON__u32(ld->ld_pattern);
  40 }
  41
  42 /* Pack LOV object metadata for shipment to the MDS.
  43  *
  44  * XXX In the future, this will be enhanced to get the EA size from the
  45  *     underlying OSC device(s) to get their EA sizes so we can stack
  46  *     LOVs properly.  For now lov_mds_md_size() just assumes one obd_id
  47  *     per stripe.
  48  */
  49 int lov_packmd(struct lustre_handle *conn, struct lov_mds_md **lmmp,
  50                struct lov_stripe_md *lsm)
  51 {
  52         struct obd_device *obd = class_conn2obd(conn);
  53         struct lov_obd *lov = &obd->u.lov;
  54         struct lov_oinfo *loi;
  55         struct lov_mds_md *lmm;
  56         int ost_count = lov->desc.ld_tgt_count;
  57         int stripe_count = ost_count;
  58         int lmm_size;
  59         int i;
  60         ENTRY;
  61
  62         if (lsm)
  63                 stripe_count = lsm->lsm_stripe_count;
  64
  65         /* XXX LOV STACKING call into osc for sizes */
  66         lmm_size = lov_mds_md_size(ost_count);
  67
  68         if (!lmmp)
  69                 RETURN(lmm_size);
  70
  71         if (*lmmp && !lsm) {
  72                 /* endianness */
  73                 ost_count = ((*lmmp)->lmm_ost_count);
  74                 OBD_FREE(*lmmp, lov_mds_md_size(ost_count));
  75                 *lmmp = NULL;
  76                 RETURN(0);
  77         }
  78
  79         if (!*lmmp) {
  80                 OBD_ALLOC(*lmmp, lmm_size);
  81                 if (!*lmmp)
  82                         RETURN(-ENOMEM);
  83         }
  84
  85         lmm = *lmmp;
  86
  87         lmm->lmm_stripe_count = (stripe_count);
  88         if (!lsm)
  89                 RETURN(lmm_size);
  90         /* XXX endianness */
  91         lmm->lmm_magic = (lsm->lsm_magic);
  92         lmm->lmm_object_id = (lsm->lsm_object_id);
  93         lmm->lmm_stripe_size = (lsm->lsm_stripe_size);
  94         lmm->lmm_stripe_pattern = (lsm->lsm_stripe_pattern);
  95         lmm->lmm_stripe_offset = (lsm->lsm_stripe_offset);
  96         lmm->lmm_ost_count = (lov->desc.ld_tgt_count);
  97
  98         /* Only fill in the object ids which we are actually using.
  99          * Assumes lmm_objects is otherwise zero-filled. */
 100         for (i = 0, loi = lsm->lsm_oinfo; i < stripe_count; i++, loi++)
 101                 /* XXX call down to osc_packmd() to do the packing */
 102                 lmm->lmm_objects[loi->loi_ost_idx].l_object_id = (loi->loi_id);
 103
 104         RETURN(lmm_size);
 105 }
 106
 107 int lov_unpackmd(struct lustre_handle *conn, struct lov_stripe_md **lsmp,
 108                  struct lov_mds_md *lmm)
 109 {
 110         struct obd_device *obd = class_conn2obd(conn);
 111         struct lov_obd *lov = &obd->u.lov;
 112         struct lov_stripe_md *lsm;
 113         struct lov_oinfo *loi;
 114         int ost_count = lov->desc.ld_active_tgt_count;
 115         int ost_offset = 0;
 116         int stripe_count = 0;
 117         int lsm_size;
 118         int i;
 119         ENTRY;
 120
 121         if (lmm)
 122                 /* endianness */
 123                 stripe_count = (lmm->lmm_stripe_count);
 124
 125         if (!stripe_count)
 126                 stripe_count = lov->desc.ld_default_stripe_count;
 127         if (!stripe_count || stripe_count > ost_count)
 128                 stripe_count = ost_count;
 129
 130         /* XXX LOV STACKING call into osc for sizes */
 131         lsm_size = lov_stripe_md_size(stripe_count);
 132
 133         if (!lsmp)
 134                 RETURN(lsm_size);
 135
 136         if (*lsmp && !lmm) {
 137                 stripe_count = (*lsmp)->lsm_stripe_count;
 138                 OBD_FREE(*lsmp, lov_stripe_md_size(stripe_count));
 139                 *lsmp = NULL;
 140                 RETURN(0);
 141         }
 142
 143         if (!*lsmp) {
 144                 OBD_ALLOC(*lsmp, lsm_size);
 145                 if (!*lsmp)
 146                         RETURN(-ENOMEM);
 147         }
 148
 149         lsm = *lsmp;
 150
 151         lsm->lsm_stripe_count = stripe_count;
 152         if (!lmm)
 153                 RETURN(lsm_size);
 154
 155         /* XXX endianness */
 156         ost_offset = lsm->lsm_stripe_offset = (lmm->lmm_stripe_offset);
 157         lsm->lsm_magic = (lmm->lmm_magic);
 158         lsm->lsm_object_id = (lmm->lmm_object_id);
 159         lsm->lsm_stripe_size = (lmm->lmm_stripe_size);
 160         lsm->lsm_stripe_pattern = (lmm->lmm_stripe_pattern);
 161
 162         for (i = 0, loi = lsm->lsm_oinfo; i < ost_count; i++, ost_offset++) {
 163                 ost_offset %= ost_count;
 164
 165                 if (!lmm->lmm_objects[ost_offset].l_object_id)
 166                         continue;
 167
 168                 LASSERT(loi - lsm->lsm_oinfo < stripe_count);
 169                 /* XXX LOV STACKING call down to osc_unpackmd() */
 170                 loi->loi_id = (lmm->lmm_objects[ost_offset].l_object_id);
 171                 loi->loi_ost_idx = ost_offset;
 172                 loi++;
 173         }
 174
 175         RETURN(lsm_size);
 176 }