drivers/staging/lustre/lustre/llite/llite_nfs.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, see
  18  * http://www.gnu.org/licenses/gpl-2.0.html
  19  *
  20  * GPL HEADER END
  21  */
  22 /*
  23  * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
  24  * Use is subject to license terms.
  25  *
  26  * Copyright (c) 2011, 2012, Intel Corporation.
  27  */
  28 /*
  29  * This file is part of Lustre, http://www.lustre.org/
  30  * Lustre is a trademark of Sun Microsystems, Inc.
  31  *
  32  * lustre/lustre/llite/llite_nfs.c
  33  *
  34  * NFS export of Lustre Light File System
  35  *
  36  * Author: Yury Umanets <umka@clusterfs.com>
  37  * Author: Huang Hua <huanghua@clusterfs.com>
  38  */
  39
  40 #define DEBUG_SUBSYSTEM S_LLITE
  41 #include "../include/lustre_lite.h"
  42 #include "llite_internal.h"
  43 #include <linux/exportfs.h>
  44
  45 __u32 get_uuid2int(const char *name, int len)
  46 {
  47         __u32 key0 = 0x12a3fe2d, key1 = 0x37abe8f9;
  48
  49         while (len--) {
  50                 __u32 key = key1 + (key0 ^ (*name++ * 7152373));
  51
  52                 if (key & 0x80000000)
  53                         key -= 0x7fffffff;
  54                 key1 = key0;
  55                 key0 = key;
  56         }
  57         return (key0 << 1);
  58 }
  59
  60 void get_uuid2fsid(const char *name, int len, __kernel_fsid_t *fsid)
  61 {
  62         __u64 key = 0, key0 = 0x12a3fe2d, key1 = 0x37abe8f9;
  63
  64         while (len--) {
  65                 key = key1 + (key0 ^ (*name++ * 7152373));
  66                 if (key & 0x8000000000000000ULL)
  67                         key -= 0x7fffffffffffffffULL;
  68                 key1 = key0;
  69                 key0 = key;
  70         }
  71
  72         fsid->val[0] = key;
  73         fsid->val[1] = key >> 32;
  74 }
  75
  76 struct inode *search_inode_for_lustre(struct super_block *sb,
  77                                       const struct lu_fid *fid)
  78 {
  79         struct ll_sb_info     *sbi = ll_s2sbi(sb);
  80         struct ptlrpc_request *req = NULL;
  81         struct inode      *inode = NULL;
  82         int                eadatalen = 0;
  83         unsigned long         hash = cl_fid_build_ino(fid,
  84                                                       ll_need_32bit_api(sbi));
  85         struct  md_op_data    *op_data;
  86         int                rc;
  87
  88         CDEBUG(D_INFO, "searching inode for:(%lu,"DFID")\n", hash, PFID(fid));
  89
  90         inode = ilookup5(sb, hash, ll_test_inode_by_fid, (void *)fid);
  91         if (inode)
  92                 return inode;
  93
  94         rc = ll_get_default_mdsize(sbi, &eadatalen);
  95         if (rc)
  96                 return ERR_PTR(rc);
  97
  98         /* Because inode is NULL, ll_prep_md_op_data can not
  99          * be used here. So we allocate op_data ourselves
 100          */
 101         op_data = kzalloc(sizeof(*op_data), GFP_NOFS);
 102         if (!op_data)
 103                 return ERR_PTR(-ENOMEM);
 104
 105         op_data->op_fid1 = *fid;
 106         op_data->op_mode = eadatalen;
 107         op_data->op_valid = OBD_MD_FLEASIZE;
 108
 109         /* mds_fid2dentry ignores f_type */
 110         rc = md_getattr(sbi->ll_md_exp, op_data, &req);
 111         kfree(op_data);
 112         if (rc) {
 113                 CDEBUG(D_INFO, "can't get object attrs, fid "DFID", rc %d\n",
 114                        PFID(fid), rc);
 115                 return ERR_PTR(rc);
 116         }
 117         rc = ll_prep_inode(&inode, req, sb, NULL);
 118         ptlrpc_req_finished(req);
 119         if (rc)
 120                 return ERR_PTR(rc);
 121
 122         return inode;
 123 }
 124
 125 struct lustre_nfs_fid {
 126         struct lu_fid   lnf_child;
 127         struct lu_fid   lnf_parent;
 128 };
 129
 130 static struct dentry *
 131 ll_iget_for_nfs(struct super_block *sb, struct lu_fid *fid, struct lu_fid *parent)
 132 {
 133         struct inode  *inode;
 134         struct dentry *result;
 135
 136         if (!fid_is_sane(fid))
 137                 return ERR_PTR(-ESTALE);
 138
 139         CDEBUG(D_INFO, "Get dentry for fid: " DFID "\n", PFID(fid));
 140
 141         inode = search_inode_for_lustre(sb, fid);
 142         if (IS_ERR(inode))
 143                 return ERR_CAST(inode);
 144
 145         if (is_bad_inode(inode)) {
 146                 /* we didn't find the right inode.. */
 147                 iput(inode);
 148                 return ERR_PTR(-ESTALE);
 149         }
 150
 151         result = d_obtain_alias(inode);
 152         if (IS_ERR(result)) {
 153                 iput(inode);
 154                 return result;
 155         }
 156
 157         /**
 158          * In case d_obtain_alias() found a disconnected dentry, always update
 159          * lli_pfid to allow later operation (normally open) have parent fid,
 160          * which may be used by MDS to create data.
 161          */
 162         if (parent) {
 163                 struct ll_inode_info *lli = ll_i2info(inode);
 164
 165                 spin_lock(&lli->lli_lock);
 166                 lli->lli_pfid = *parent;
 167                 spin_unlock(&lli->lli_lock);
 168         }
 169
 170         /* N.B. d_obtain_alias() drops inode ref on error */
 171         result = d_obtain_alias(inode);
 172         if (!IS_ERR(result)) {
 173                 int rc;
 174
 175                 rc = ll_d_init(result);
 176                 if (rc < 0) {
 177                         dput(result);
 178                         result = ERR_PTR(rc);
 179                 } else {
 180                         struct ll_dentry_data *ldd = ll_d2d(result);
 181
 182                         /*
 183                          * Need to signal to the ll_intent_file_open that
 184                          * we came from NFS and so opencache needs to be
 185                          * enabled for this one
 186                          */
 187                         ldd->lld_nfs_dentry = 1;
 188                 }
 189         }
 190
 191         return result;
 192 }
 193
 194 /**
 195  * \a connectable - is nfsd will connect himself or this should be done
 196  *                at lustre
 197  *
 198  * The return value is file handle type:
 199  * 1 -- contains child file handle;
 200  * 2 -- contains child file handle and parent file handle;
 201  * 255 -- error.
 202  */
 203 static int ll_encode_fh(struct inode *inode, __u32 *fh, int *plen,
 204                         struct inode *parent)
 205 {
 206         int fileid_len = sizeof(struct lustre_nfs_fid) / 4;
 207         struct lustre_nfs_fid *nfs_fid = (void *)fh;
 208
 209         CDEBUG(D_INFO, "%s: encoding for ("DFID") maxlen=%d minlen=%d\n",
 210                ll_get_fsname(inode->i_sb, NULL, 0),
 211                PFID(ll_inode2fid(inode)), *plen, fileid_len);
 212
 213         if (*plen < fileid_len) {
 214                 *plen = fileid_len;
 215                 return FILEID_INVALID;
 216         }
 217
 218         nfs_fid->lnf_child = *ll_inode2fid(inode);
 219         if (parent)
 220                 nfs_fid->lnf_parent = *ll_inode2fid(parent);
 221         else
 222                 fid_zero(&nfs_fid->lnf_parent);
 223         *plen = fileid_len;
 224
 225         return FILEID_LUSTRE;
 226 }
 227
 228 static int ll_nfs_get_name_filldir(struct dir_context *ctx, const char *name,
 229                                    int namelen, loff_t hash, u64 ino,
 230                                    unsigned type)
 231 {
 232         /* It is hack to access lde_fid for comparison with lgd_fid.
 233          * So the input 'name' must be part of the 'lu_dirent'.
 234          */
 235         struct lu_dirent *lde = container_of0(name, struct lu_dirent, lde_name);
 236         struct ll_getname_data *lgd =
 237                 container_of(ctx, struct ll_getname_data, ctx);
 238         struct lu_fid fid;
 239
 240         fid_le_to_cpu(&fid, &lde->lde_fid);
 241         if (lu_fid_eq(&fid, &lgd->lgd_fid)) {
 242                 memcpy(lgd->lgd_name, name, namelen);
 243                 lgd->lgd_name[namelen] = 0;
 244                 lgd->lgd_found = 1;
 245         }
 246         return lgd->lgd_found;
 247 }
 248
 249 static int ll_get_name(struct dentry *dentry, char *name,
 250                        struct dentry *child)
 251 {
 252         struct inode *dir = d_inode(dentry);
 253         int rc;
 254         struct ll_getname_data lgd = {
 255                 .lgd_name = name,
 256                 .lgd_fid = ll_i2info(d_inode(child))->lli_fid,
 257                 .ctx.actor = ll_nfs_get_name_filldir,
 258         };
 259         struct md_op_data *op_data;
 260         __u64 pos = 0;
 261
 262         if (!dir || !S_ISDIR(dir->i_mode)) {
 263                 rc = -ENOTDIR;
 264                 goto out;
 265         }
 266
 267         if (!dir->i_fop) {
 268                 rc = -EINVAL;
 269                 goto out;
 270         }
 271
 272         op_data = ll_prep_md_op_data(NULL, dir, dir, NULL, 0, 0,
 273                                      LUSTRE_OPC_ANY, dir);
 274         if (IS_ERR(op_data)) {
 275                 rc = PTR_ERR(op_data);
 276                 goto out;
 277         }
 278
 279         op_data->op_max_pages = ll_i2sbi(dir)->ll_md_brw_pages;
 280         inode_lock(dir);
 281         rc = ll_dir_read(dir, &pos, op_data, &lgd.ctx);
 282         inode_unlock(dir);
 283         ll_finish_md_op_data(op_data);
 284         if (!rc && !lgd.lgd_found)
 285                 rc = -ENOENT;
 286 out:
 287         return rc;
 288 }
 289
 290 static struct dentry *ll_fh_to_dentry(struct super_block *sb, struct fid *fid,
 291                                       int fh_len, int fh_type)
 292 {
 293         struct lustre_nfs_fid *nfs_fid = (struct lustre_nfs_fid *)fid;
 294
 295         if (fh_type != FILEID_LUSTRE)
 296                 return ERR_PTR(-EPROTO);
 297
 298         return ll_iget_for_nfs(sb, &nfs_fid->lnf_child, &nfs_fid->lnf_parent);
 299 }
 300
 301 static struct dentry *ll_fh_to_parent(struct super_block *sb, struct fid *fid,
 302                                       int fh_len, int fh_type)
 303 {
 304         struct lustre_nfs_fid *nfs_fid = (struct lustre_nfs_fid *)fid;
 305
 306         if (fh_type != FILEID_LUSTRE)
 307                 return ERR_PTR(-EPROTO);
 308
 309         return ll_iget_for_nfs(sb, &nfs_fid->lnf_parent, NULL);
 310 }
 311
 312 int ll_dir_get_parent_fid(struct inode *dir, struct lu_fid *parent_fid)
 313 {
 314         struct ptlrpc_request *req = NULL;
 315         struct ll_sb_info     *sbi;
 316         struct mdt_body       *body;
 317         static const char dotdot[] = "..";
 318         struct md_op_data     *op_data;
 319         int                rc;
 320         int                   lmmsize;
 321
 322         LASSERT(dir && S_ISDIR(dir->i_mode));
 323
 324         sbi = ll_s2sbi(dir->i_sb);
 325
 326         CDEBUG(D_INFO, "%s: getting parent for ("DFID")\n",
 327                ll_get_fsname(dir->i_sb, NULL, 0),
 328                PFID(ll_inode2fid(dir)));
 329
 330         rc = ll_get_default_mdsize(sbi, &lmmsize);
 331         if (rc != 0)
 332                 return rc;
 333
 334         op_data = ll_prep_md_op_data(NULL, dir, NULL, dotdot,
 335                                      strlen(dotdot), lmmsize,
 336                                      LUSTRE_OPC_ANY, NULL);
 337         if (IS_ERR(op_data))
 338                 return PTR_ERR(op_data);
 339
 340         rc = md_getattr_name(sbi->ll_md_exp, op_data, &req);
 341         ll_finish_md_op_data(op_data);
 342         if (rc) {
 343                 CERROR("%s: failure inode "DFID" get parent: rc = %d\n",
 344                        ll_get_fsname(dir->i_sb, NULL, 0),
 345                        PFID(ll_inode2fid(dir)), rc);
 346                 return rc;
 347         }
 348         body = req_capsule_server_get(&req->rq_pill, &RMF_MDT_BODY);
 349         /*
 350          * LU-3952: MDT may lost the FID of its parent, we should not crash
 351          * the NFS server, ll_iget_for_nfs() will handle the error.
 352          */
 353         if (body->mbo_valid & OBD_MD_FLID) {
 354                 CDEBUG(D_INFO, "parent for " DFID " is " DFID "\n",
 355                        PFID(ll_inode2fid(dir)), PFID(&body->mbo_fid1));
 356                 *parent_fid = body->mbo_fid1;
 357         }
 358
 359         ptlrpc_req_finished(req);
 360         return 0;
 361 }
 362
 363 static struct dentry *ll_get_parent(struct dentry *dchild)
 364 {
 365         struct lu_fid parent_fid = { 0 };
 366         struct dentry *dentry;
 367         int rc;
 368
 369         rc = ll_dir_get_parent_fid(dchild->d_inode, &parent_fid);
 370         if (rc)
 371                 return ERR_PTR(rc);
 372
 373         dentry = ll_iget_for_nfs(dchild->d_inode->i_sb, &parent_fid, NULL);
 374
 375         return dentry;
 376 }
 377
 378 const struct export_operations lustre_export_operations = {
 379         .get_parent = ll_get_parent,
 380         .encode_fh  = ll_encode_fh,
 381         .get_name   = ll_get_name,
 382         .fh_to_dentry = ll_fh_to_dentry,
 383         .fh_to_parent = ll_fh_to_parent,
 384 };