drivers/staging/lustre/lustre/obdclass/md_attrs.c

   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, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * General Public License version 2 for more details (a copy is included
  14  * in the LICENSE file that accompanied this code).
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * version 2 along with this program; if not, write to the
  18  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  19  * Boston, MA 021110-1307, USA
  20  *
  21  * GPL HEADER END
  22  */
  23 /*
  24  * Copyright (c) 2012, Intel Corporation.
  25  * Use is subject to license terms.
  26  *
  27  * Author: Johann Lombardi <johann.lombardi@intel.com>
  28  */
  29
  30 #include <lustre/lustre_idl.h>
  31 #include <obd.h>
  32 #include <md_object.h>
  33
  34 /**
  35  * Initialize new \a lma. Only fid is stored.
  36  *
  37  * \param lma - is the new LMA structure to be initialized
  38  * \param fid - is the FID of the object this LMA belongs to
  39  * \param incompat - features that MDS must understand to access object
  40  */
  41 void lustre_lma_init(struct lustre_mdt_attrs *lma, const struct lu_fid *fid,
  42                      __u32 incompat)
  43 {
  44         lma->lma_compat   = 0;
  45         lma->lma_incompat = incompat;
  46         lma->lma_self_fid = *fid;
  47
  48         /* If a field is added in struct lustre_mdt_attrs, zero it explicitly
  49          * and change the test below. */
  50         LASSERT(sizeof(*lma) ==
  51                 (offsetof(struct lustre_mdt_attrs, lma_self_fid) +
  52                  sizeof(lma->lma_self_fid)));
  53 };
  54 EXPORT_SYMBOL(lustre_lma_init);
  55
  56 /**
  57  * Swab, if needed, LMA structure which is stored on-disk in little-endian order.
  58  *
  59  * \param lma - is a pointer to the LMA structure to be swabbed.
  60  */
  61 void lustre_lma_swab(struct lustre_mdt_attrs *lma)
  62 {
  63         /* Use LUSTRE_MSG_MAGIC to detect local endianness. */
  64         if (LUSTRE_MSG_MAGIC != cpu_to_le32(LUSTRE_MSG_MAGIC)) {
  65                 __swab32s(&lma->lma_compat);
  66                 __swab32s(&lma->lma_incompat);
  67                 lustre_swab_lu_fid(&lma->lma_self_fid);
  68         }
  69 };
  70 EXPORT_SYMBOL(lustre_lma_swab);
  71
  72 /**
  73  * Swab, if needed, SOM structure which is stored on-disk in little-endian
  74  * order.
  75  *
  76  * \param attrs - is a pointer to the SOM structure to be swabbed.
  77  */
  78 void lustre_som_swab(struct som_attrs *attrs)
  79 {
  80         /* Use LUSTRE_MSG_MAGIC to detect local endianness. */
  81         if (LUSTRE_MSG_MAGIC != cpu_to_le32(LUSTRE_MSG_MAGIC)) {
  82                 __swab32s(&attrs->som_compat);
  83                 __swab32s(&attrs->som_incompat);
  84                 __swab64s(&attrs->som_ioepoch);
  85                 __swab64s(&attrs->som_size);
  86                 __swab64s(&attrs->som_blocks);
  87                 __swab64s(&attrs->som_mountid);
  88         }
  89 };
  90 EXPORT_SYMBOL(lustre_som_swab);
  91
  92 /*
  93  * Swab and extract SOM attributes from on-disk xattr.
  94  *
  95  * \param buf - is a buffer containing the on-disk SOM extended attribute.
  96  * \param rc  - is the SOM xattr stored in \a buf
  97  * \param msd - is the md_som_data structure where to extract SOM attributes.
  98  */
  99 int lustre_buf2som(void *buf, int rc, struct md_som_data *msd)
 100 {
 101         struct som_attrs *attrs = (struct som_attrs *)buf;
 102
 103         if (rc == 0 ||  rc == -ENODATA)
 104                 /* no SOM attributes */
 105                 return -ENODATA;
 106
 107         if (rc < 0)
 108                 /* error hit while fetching xattr */
 109                 return rc;
 110
 111         /* check SOM compatibility */
 112         if (attrs->som_incompat & ~cpu_to_le32(SOM_INCOMPAT_SUPP))
 113                 return -ENODATA;
 114
 115         /* unpack SOM attributes */
 116         lustre_som_swab(attrs);
 117
 118         /* fill in-memory msd structure */
 119         msd->msd_compat   = attrs->som_compat;
 120         msd->msd_incompat = attrs->som_incompat;
 121         msd->msd_ioepoch  = attrs->som_ioepoch;
 122         msd->msd_size     = attrs->som_size;
 123         msd->msd_blocks   = attrs->som_blocks;
 124         msd->msd_mountid  = attrs->som_mountid;
 125
 126         return 0;
 127 }
 128 EXPORT_SYMBOL(lustre_buf2som);
 129
 130 /**
 131  * Swab, if needed, HSM structure which is stored on-disk in little-endian
 132  * order.
 133  *
 134  * \param attrs - is a pointer to the HSM structure to be swabbed.
 135  */
 136 void lustre_hsm_swab(struct hsm_attrs *attrs)
 137 {
 138         /* Use LUSTRE_MSG_MAGIC to detect local endianness. */
 139         if (LUSTRE_MSG_MAGIC != cpu_to_le32(LUSTRE_MSG_MAGIC)) {
 140                 __swab32s(&attrs->hsm_compat);
 141                 __swab32s(&attrs->hsm_flags);
 142                 __swab64s(&attrs->hsm_arch_id);
 143                 __swab64s(&attrs->hsm_arch_ver);
 144         }
 145 };
 146 EXPORT_SYMBOL(lustre_hsm_swab);
 147
 148 /*
 149  * Swab and extract HSM attributes from on-disk xattr.
 150  *
 151  * \param buf - is a buffer containing the on-disk HSM extended attribute.
 152  * \param rc  - is the HSM xattr stored in \a buf
 153  * \param mh  - is the md_hsm structure where to extract HSM attributes.
 154  */
 155 int lustre_buf2hsm(void *buf, int rc, struct md_hsm *mh)
 156 {
 157         struct hsm_attrs *attrs = (struct hsm_attrs *)buf;
 158
 159         if (rc == 0 ||  rc == -ENODATA)
 160                 /* no HSM attributes */
 161                 return -ENODATA;
 162
 163         if (rc < 0)
 164                 /* error hit while fetching xattr */
 165                 return rc;
 166
 167         /* unpack HSM attributes */
 168         lustre_hsm_swab(attrs);
 169
 170         /* fill md_hsm structure */
 171         mh->mh_compat   = attrs->hsm_compat;
 172         mh->mh_flags    = attrs->hsm_flags;
 173         mh->mh_arch_id  = attrs->hsm_arch_id;
 174         mh->mh_arch_ver = attrs->hsm_arch_ver;
 175
 176         return 0;
 177 }
 178 EXPORT_SYMBOL(lustre_buf2hsm);
 179
 180 /*
 181  * Pack HSM attributes.
 182  *
 183  * \param buf - is the output buffer where to pack the on-disk HSM xattr.
 184  * \param mh  - is the md_hsm structure to pack.
 185  */
 186 void lustre_hsm2buf(void *buf, struct md_hsm *mh)
 187 {
 188         struct hsm_attrs *attrs = (struct hsm_attrs *)buf;
 189
 190         /* copy HSM attributes */
 191         attrs->hsm_compat   = mh->mh_compat;
 192         attrs->hsm_flags    = mh->mh_flags;
 193         attrs->hsm_arch_id  = mh->mh_arch_id;
 194         attrs->hsm_arch_ver = mh->mh_arch_ver;
 195
 196         /* pack xattr */
 197         lustre_hsm_swab(attrs);
 198 }
 199 EXPORT_SYMBOL(lustre_hsm2buf);