drivers/staging/lustre/lustre/lmv/lmv_intent.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.sun.com/software/products/lustre/docs/GPLv2.pdf
  19  *
  20  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  21  * CA 95054 USA or visit www.sun.com if you need additional information or
  22  * have any questions.
  23  *
  24  * GPL HEADER END
  25  */
  26 /*
  27  * Copyright (c) 2004, 2010, Oracle and/or its affiliates. All rights reserved.
  28  * Use is subject to license terms.
  29  *
  30  * Copyright (c) 2011, 2012, Intel Corporation.
  31  */
  32 /*
  33  * This file is part of Lustre, http://www.lustre.org/
  34  * Lustre is a trademark of Sun Microsystems, Inc.
  35  */
  36
  37 #define DEBUG_SUBSYSTEM S_LMV
  38 #include <linux/slab.h>
  39 #include <linux/module.h>
  40 #include <linux/init.h>
  41 #include <linux/slab.h>
  42 #include <linux/pagemap.h>
  43 #include <asm/div64.h>
  44 #include <linux/seq_file.h>
  45 #include <linux/namei.h>
  46 #include <linux/lustre_intent.h>
  47
  48 #include <obd_support.h>
  49 #include <lustre/lustre_idl.h>
  50 #include <lustre_lib.h>
  51 #include <lustre_net.h>
  52 #include <lustre_dlm.h>
  53 #include <obd_class.h>
  54 #include <lprocfs_status.h>
  55 #include "lmv_internal.h"
  56
  57 static int lmv_intent_remote(struct obd_export *exp, void *lmm,
  58                              int lmmsize, struct lookup_intent *it,
  59                              const struct lu_fid *parent_fid, int flags,
  60                              struct ptlrpc_request **reqp,
  61                              ldlm_blocking_callback cb_blocking,
  62                              __u64 extra_lock_flags)
  63 {
  64         struct obd_device       *obd = exp->exp_obd;
  65         struct lmv_obd          *lmv = &obd->u.lmv;
  66         struct ptlrpc_request   *req = NULL;
  67         struct lustre_handle    plock;
  68         struct md_op_data       *op_data;
  69         struct lmv_tgt_desc     *tgt;
  70         struct mdt_body         *body;
  71         int                     pmode;
  72         int                     rc = 0;
  73         ENTRY;
  74
  75         body = req_capsule_server_get(&(*reqp)->rq_pill, &RMF_MDT_BODY);
  76         if (body == NULL)
  77                 RETURN(-EPROTO);
  78
  79         LASSERT((body->valid & OBD_MD_MDS));
  80
  81         /*
  82          * Unfortunately, we have to lie to MDC/MDS to retrieve
  83          * attributes llite needs and provideproper locking.
  84          */
  85         if (it->it_op & IT_LOOKUP)
  86                 it->it_op = IT_GETATTR;
  87
  88         /*
  89          * We got LOOKUP lock, but we really need attrs.
  90          */
  91         pmode = it->d.lustre.it_lock_mode;
  92         if (pmode) {
  93                 plock.cookie = it->d.lustre.it_lock_handle;
  94                 it->d.lustre.it_lock_mode = 0;
  95                 it->d.lustre.it_data = NULL;
  96         }
  97
  98         LASSERT(fid_is_sane(&body->fid1));
  99
 100         tgt = lmv_find_target(lmv, &body->fid1);
 101         if (IS_ERR(tgt))
 102                 GOTO(out, rc = PTR_ERR(tgt));
 103
 104         OBD_ALLOC_PTR(op_data);
 105         if (op_data == NULL)
 106                 GOTO(out, rc = -ENOMEM);
 107
 108         op_data->op_fid1 = body->fid1;
 109         /* Sent the parent FID to the remote MDT */
 110         if (parent_fid != NULL) {
 111                 /* The parent fid is only for remote open to
 112                  * check whether the open is from OBF,
 113                  * see mdt_cross_open */
 114                 LASSERT(it->it_op & IT_OPEN);
 115                 op_data->op_fid2 = *parent_fid;
 116                 /* Add object FID to op_fid3, in case it needs to check stale
 117                  * (M_CHECK_STALE), see mdc_finish_intent_lock */
 118                 op_data->op_fid3 = body->fid1;
 119         }
 120
 121         op_data->op_bias = MDS_CROSS_REF;
 122         CDEBUG(D_INODE, "REMOTE_INTENT with fid="DFID" -> mds #%d\n",
 123                PFID(&body->fid1), tgt->ltd_idx);
 124
 125         it->d.lustre.it_disposition &= ~DISP_ENQ_COMPLETE;
 126         rc = md_intent_lock(tgt->ltd_exp, op_data, lmm, lmmsize, it,
 127                             flags, &req, cb_blocking, extra_lock_flags);
 128         if (rc)
 129                 GOTO(out_free_op_data, rc);
 130
 131         /*
 132          * LLite needs LOOKUP lock to track dentry revocation in order to
 133          * maintain dcache consistency. Thus drop UPDATE|PERM lock here
 134          * and put LOOKUP in request.
 135          */
 136         if (it->d.lustre.it_lock_mode != 0) {
 137                 it->d.lustre.it_remote_lock_handle =
 138                                         it->d.lustre.it_lock_handle;
 139                 it->d.lustre.it_remote_lock_mode = it->d.lustre.it_lock_mode;
 140         }
 141
 142         it->d.lustre.it_lock_handle = plock.cookie;
 143         it->d.lustre.it_lock_mode = pmode;
 144
 145         EXIT;
 146 out_free_op_data:
 147         OBD_FREE_PTR(op_data);
 148 out:
 149         if (rc && pmode)
 150                 ldlm_lock_decref(&plock, pmode);
 151
 152         ptlrpc_req_finished(*reqp);
 153         *reqp = req;
 154         return rc;
 155 }
 156
 157 /*
 158  * IT_OPEN is intended to open (and create, possible) an object. Parent (pid)
 159  * may be split dir.
 160  */
 161 int lmv_intent_open(struct obd_export *exp, struct md_op_data *op_data,
 162                     void *lmm, int lmmsize, struct lookup_intent *it,
 163                     int flags, struct ptlrpc_request **reqp,
 164                     ldlm_blocking_callback cb_blocking,
 165                     __u64 extra_lock_flags)
 166 {
 167         struct obd_device       *obd = exp->exp_obd;
 168         struct lmv_obd          *lmv = &obd->u.lmv;
 169         struct lmv_tgt_desc     *tgt;
 170         struct mdt_body         *body;
 171         int                     rc;
 172         ENTRY;
 173
 174         tgt = lmv_locate_mds(lmv, op_data, &op_data->op_fid1);
 175         if (IS_ERR(tgt))
 176                 RETURN(PTR_ERR(tgt));
 177
 178         /* If it is ready to open the file by FID, do not need
 179          * allocate FID at all, otherwise it will confuse MDT */
 180         if ((it->it_op & IT_CREAT) &&
 181             !(it->it_flags & MDS_OPEN_BY_FID)) {
 182                 /*
 183                  * For open with IT_CREATE and for IT_CREATE cases allocate new
 184                  * fid and setup FLD for it.
 185                  */
 186                 op_data->op_fid3 = op_data->op_fid2;
 187                 rc = lmv_fid_alloc(exp, &op_data->op_fid2, op_data);
 188                 if (rc != 0)
 189                         RETURN(rc);
 190         }
 191
 192         CDEBUG(D_INODE, "OPEN_INTENT with fid1="DFID", fid2="DFID","
 193                " name='%s' -> mds #%d\n", PFID(&op_data->op_fid1),
 194                PFID(&op_data->op_fid2), op_data->op_name, tgt->ltd_idx);
 195
 196         rc = md_intent_lock(tgt->ltd_exp, op_data, lmm, lmmsize, it, flags,
 197                             reqp, cb_blocking, extra_lock_flags);
 198         if (rc != 0)
 199                 RETURN(rc);
 200         /*
 201          * Nothing is found, do not access body->fid1 as it is zero and thus
 202          * pointless.
 203          */
 204         if ((it->d.lustre.it_disposition & DISP_LOOKUP_NEG) &&
 205             !(it->d.lustre.it_disposition & DISP_OPEN_CREATE) &&
 206             !(it->d.lustre.it_disposition & DISP_OPEN_OPEN))
 207                 RETURN(rc);
 208
 209         body = req_capsule_server_get(&(*reqp)->rq_pill, &RMF_MDT_BODY);
 210         if (body == NULL)
 211                 RETURN(-EPROTO);
 212         /*
 213          * Not cross-ref case, just get out of here.
 214          */
 215         if (likely(!(body->valid & OBD_MD_MDS)))
 216                 RETURN(0);
 217
 218         /*
 219          * Okay, MDS has returned success. Probably name has been resolved in
 220          * remote inode.
 221          */
 222         rc = lmv_intent_remote(exp, lmm, lmmsize, it, &op_data->op_fid1, flags,
 223                                reqp, cb_blocking, extra_lock_flags);
 224         if (rc != 0) {
 225                 LASSERT(rc < 0);
 226                 /*
 227                  * This is possible, that some userspace application will try to
 228                  * open file as directory and we will have -ENOTDIR here. As
 229                  * this is normal situation, we should not print error here,
 230                  * only debug info.
 231                  */
 232                 CDEBUG(D_INODE, "Can't handle remote %s: dir "DFID"("DFID"):"
 233                        "%*s: %d\n", LL_IT2STR(it), PFID(&op_data->op_fid2),
 234                        PFID(&op_data->op_fid1), op_data->op_namelen,
 235                        op_data->op_name, rc);
 236                 RETURN(rc);
 237         }
 238
 239         RETURN(rc);
 240 }
 241
 242 /*
 243  * Handler for: getattr, lookup and revalidate cases.
 244  */
 245 int lmv_intent_lookup(struct obd_export *exp, struct md_op_data *op_data,
 246                       void *lmm, int lmmsize, struct lookup_intent *it,
 247                       int flags, struct ptlrpc_request **reqp,
 248                       ldlm_blocking_callback cb_blocking,
 249                       __u64 extra_lock_flags)
 250 {
 251         struct obd_device      *obd = exp->exp_obd;
 252         struct lmv_obd   *lmv = &obd->u.lmv;
 253         struct lmv_tgt_desc    *tgt = NULL;
 254         struct mdt_body *body;
 255         int                  rc = 0;
 256         ENTRY;
 257
 258         tgt = lmv_locate_mds(lmv, op_data, &op_data->op_fid1);
 259         if (IS_ERR(tgt))
 260                 RETURN(PTR_ERR(tgt));
 261
 262         if (!fid_is_sane(&op_data->op_fid2))
 263                 fid_zero(&op_data->op_fid2);
 264
 265         CDEBUG(D_INODE, "LOOKUP_INTENT with fid1="DFID", fid2="DFID
 266                ", name='%s' -> mds #%d\n", PFID(&op_data->op_fid1),
 267                PFID(&op_data->op_fid2),
 268                op_data->op_name ? op_data->op_name : "<NULL>",
 269                tgt->ltd_idx);
 270
 271         op_data->op_bias &= ~MDS_CROSS_REF;
 272
 273         rc = md_intent_lock(tgt->ltd_exp, op_data, lmm, lmmsize, it,
 274                              flags, reqp, cb_blocking, extra_lock_flags);
 275
 276         if (rc < 0 || *reqp == NULL)
 277                 RETURN(rc);
 278
 279         /*
 280          * MDS has returned success. Probably name has been resolved in
 281          * remote inode. Let's check this.
 282          */
 283         body = req_capsule_server_get(&(*reqp)->rq_pill, &RMF_MDT_BODY);
 284         if (body == NULL)
 285                 RETURN(-EPROTO);
 286         /* Not cross-ref case, just get out of here. */
 287         if (likely(!(body->valid & OBD_MD_MDS)))
 288                 RETURN(0);
 289
 290         rc = lmv_intent_remote(exp, lmm, lmmsize, it, NULL, flags, reqp,
 291                                cb_blocking, extra_lock_flags);
 292
 293         RETURN(rc);
 294 }
 295
 296 int lmv_intent_lock(struct obd_export *exp, struct md_op_data *op_data,
 297                     void *lmm, int lmmsize, struct lookup_intent *it,
 298                     int flags, struct ptlrpc_request **reqp,
 299                     ldlm_blocking_callback cb_blocking,
 300                     __u64 extra_lock_flags)
 301 {
 302         struct obd_device *obd = exp->exp_obd;
 303         int             rc;
 304         ENTRY;
 305
 306         LASSERT(it != NULL);
 307         LASSERT(fid_is_sane(&op_data->op_fid1));
 308
 309         CDEBUG(D_INODE, "INTENT LOCK '%s' for '%*s' on "DFID"\n",
 310                LL_IT2STR(it), op_data->op_namelen, op_data->op_name,
 311                PFID(&op_data->op_fid1));
 312
 313         rc = lmv_check_connect(obd);
 314         if (rc)
 315                 RETURN(rc);
 316
 317         if (it->it_op & (IT_LOOKUP | IT_GETATTR | IT_LAYOUT))
 318                 rc = lmv_intent_lookup(exp, op_data, lmm, lmmsize, it,
 319                                        flags, reqp, cb_blocking,
 320                                        extra_lock_flags);
 321         else if (it->it_op & IT_OPEN)
 322                 rc = lmv_intent_open(exp, op_data, lmm, lmmsize, it,
 323                                      flags, reqp, cb_blocking,
 324                                      extra_lock_flags);
 325         else
 326                 LBUG();
 327         RETURN(rc);
 328 }