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LU-169 lov: add basic infrastructure for layout lock
[fs/lustre-release.git] / lustre / mdc / mdc_locks.c
1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
2  * vim:expandtab:shiftwidth=8:tabstop=8:
3  *
4  * GPL HEADER START
5  *
6  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License version 2 only,
10  * as published by the Free Software Foundation.
11  *
12  * This program is distributed in the hope that it will be useful, but
13  * WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15  * General Public License version 2 for more details (a copy is included
16  * in the LICENSE file that accompanied this code).
17  *
18  * You should have received a copy of the GNU General Public License
19  * version 2 along with this program; If not, see
20  * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
21  *
22  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
23  * CA 95054 USA or visit www.sun.com if you need additional information or
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25  *
26  * GPL HEADER END
27  */
28 /*
29  * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
30  * Use is subject to license terms.
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 #ifndef EXPORT_SYMTAB
38 # define EXPORT_SYMTAB
39 #endif
40 #define DEBUG_SUBSYSTEM S_MDC
41
42 #ifdef __KERNEL__
43 # include <linux/module.h>
44 # include <linux/pagemap.h>
45 # include <linux/miscdevice.h>
46 # include <linux/init.h>
47 #else
48 # include <liblustre.h>
49 #endif
50
51 #include <lustre_acl.h>
52 #include <obd_class.h>
53 #include <lustre_dlm.h>
54 /* fid_res_name_eq() */
55 #include <lustre_fid.h>
56 #include <lprocfs_status.h>
57 #include "mdc_internal.h"
58
59 struct mdc_getattr_args {
60         struct obd_export           *ga_exp;
61         struct md_enqueue_info      *ga_minfo;
62         struct ldlm_enqueue_info    *ga_einfo;
63 };
64
65 int it_disposition(struct lookup_intent *it, int flag)
66 {
67         return it->d.lustre.it_disposition & flag;
68 }
69 EXPORT_SYMBOL(it_disposition);
70
71 void it_set_disposition(struct lookup_intent *it, int flag)
72 {
73         it->d.lustre.it_disposition |= flag;
74 }
75 EXPORT_SYMBOL(it_set_disposition);
76
77 void it_clear_disposition(struct lookup_intent *it, int flag)
78 {
79         it->d.lustre.it_disposition &= ~flag;
80 }
81 EXPORT_SYMBOL(it_clear_disposition);
82
83 int it_open_error(int phase, struct lookup_intent *it)
84 {
85         if (it_disposition(it, DISP_OPEN_OPEN)) {
86                 if (phase >= DISP_OPEN_OPEN)
87                         return it->d.lustre.it_status;
88                 else
89                         return 0;
90         }
91
92         if (it_disposition(it, DISP_OPEN_CREATE)) {
93                 if (phase >= DISP_OPEN_CREATE)
94                         return it->d.lustre.it_status;
95                 else
96                         return 0;
97         }
98
99         if (it_disposition(it, DISP_LOOKUP_EXECD)) {
100                 if (phase >= DISP_LOOKUP_EXECD)
101                         return it->d.lustre.it_status;
102                 else
103                         return 0;
104         }
105
106         if (it_disposition(it, DISP_IT_EXECD)) {
107                 if (phase >= DISP_IT_EXECD)
108                         return it->d.lustre.it_status;
109                 else
110                         return 0;
111         }
112         CERROR("it disp: %X, status: %d\n", it->d.lustre.it_disposition,
113                it->d.lustre.it_status);
114         LBUG();
115         return 0;
116 }
117 EXPORT_SYMBOL(it_open_error);
118
119 /* this must be called on a lockh that is known to have a referenced lock */
120 int mdc_set_lock_data(struct obd_export *exp, __u64 *lockh, void *data,
121                       __u64 *bits)
122 {
123         struct ldlm_lock *lock;
124         ENTRY;
125
126         if(bits)
127                 *bits = 0;
128
129         if (!*lockh)
130                 RETURN(0);
131
132         lock = ldlm_handle2lock((struct lustre_handle *)lockh);
133
134         LASSERT(lock != NULL);
135         lock_res_and_lock(lock);
136 #ifdef __KERNEL__
137         if (lock->l_ast_data && lock->l_ast_data != data) {
138                 struct inode *new_inode = data;
139                 struct inode *old_inode = lock->l_ast_data;
140                 LASSERTF(old_inode->i_state & I_FREEING,
141                          "Found existing inode %p/%lu/%u state %lu in lock: "
142                          "setting data to %p/%lu/%u\n", old_inode,
143                          old_inode->i_ino, old_inode->i_generation,
144                          old_inode->i_state,
145                          new_inode, new_inode->i_ino, new_inode->i_generation);
146         }
147 #endif
148         lock->l_ast_data = data;
149         if (bits)
150                 *bits = lock->l_policy_data.l_inodebits.bits;
151
152         unlock_res_and_lock(lock);
153         LDLM_LOCK_PUT(lock);
154
155         RETURN(0);
156 }
157
158 ldlm_mode_t mdc_lock_match(struct obd_export *exp, int flags,
159                            const struct lu_fid *fid, ldlm_type_t type,
160                            ldlm_policy_data_t *policy, ldlm_mode_t mode,
161                            struct lustre_handle *lockh)
162 {
163         struct ldlm_res_id res_id;
164         ldlm_mode_t rc;
165         ENTRY;
166
167         fid_build_reg_res_name(fid, &res_id);
168         rc = ldlm_lock_match(class_exp2obd(exp)->obd_namespace, flags,
169                              &res_id, type, policy, mode, lockh, 0);
170         RETURN(rc);
171 }
172
173 int mdc_cancel_unused(struct obd_export *exp,
174                       const struct lu_fid *fid,
175                       ldlm_policy_data_t *policy,
176                       ldlm_mode_t mode,
177                       ldlm_cancel_flags_t flags,
178                       void *opaque)
179 {
180         struct ldlm_res_id res_id;
181         struct obd_device *obd = class_exp2obd(exp);
182         int rc;
183
184         ENTRY;
185
186         fid_build_reg_res_name(fid, &res_id);
187         rc = ldlm_cli_cancel_unused_resource(obd->obd_namespace, &res_id,
188                                              policy, mode, flags, opaque);
189         RETURN(rc);
190 }
191
192 int mdc_change_cbdata(struct obd_export *exp,
193                       const struct lu_fid *fid,
194                       ldlm_iterator_t it, void *data)
195 {
196         struct ldlm_res_id res_id;
197         ENTRY;
198
199         fid_build_reg_res_name(fid, &res_id);
200         ldlm_resource_iterate(class_exp2obd(exp)->obd_namespace,
201                               &res_id, it, data);
202
203         EXIT;
204         return 0;
205 }
206
207 /* find any ldlm lock of the inode in mdc
208  * return 0    not find
209  *        1    find one
210  *      < 0    error */
211 int mdc_find_cbdata(struct obd_export *exp,
212                     const struct lu_fid *fid,
213                     ldlm_iterator_t it, void *data)
214 {
215         struct ldlm_res_id res_id;
216         int rc = 0;
217         ENTRY;
218
219         fid_build_reg_res_name((struct lu_fid*)fid, &res_id);
220         rc = ldlm_resource_iterate(class_exp2obd(exp)->obd_namespace, &res_id,
221                                    it, data);
222         if (rc == LDLM_ITER_STOP)
223                 RETURN(1);
224         else if (rc == LDLM_ITER_CONTINUE)
225                 RETURN(0);
226         RETURN(rc);
227 }
228
229 static inline void mdc_clear_replay_flag(struct ptlrpc_request *req, int rc)
230 {
231         /* Don't hold error requests for replay. */
232         if (req->rq_replay) {
233                 cfs_spin_lock(&req->rq_lock);
234                 req->rq_replay = 0;
235                 cfs_spin_unlock(&req->rq_lock);
236         }
237         if (rc && req->rq_transno != 0) {
238                 DEBUG_REQ(D_ERROR, req, "transno returned on error rc %d", rc);
239                 LBUG();
240         }
241 }
242
243 /* Save a large LOV EA into the request buffer so that it is available
244  * for replay.  We don't do this in the initial request because the
245  * original request doesn't need this buffer (at most it sends just the
246  * lov_mds_md) and it is a waste of RAM/bandwidth to send the empty
247  * buffer and may also be difficult to allocate and save a very large
248  * request buffer for each open. (bug 5707)
249  *
250  * OOM here may cause recovery failure if lmm is needed (only for the
251  * original open if the MDS crashed just when this client also OOM'd)
252  * but this is incredibly unlikely, and questionable whether the client
253  * could do MDS recovery under OOM anyways... */
254 static void mdc_realloc_openmsg(struct ptlrpc_request *req,
255                                 struct mdt_body *body)
256 {
257         int     rc;
258
259         /* FIXME: remove this explicit offset. */
260         rc = sptlrpc_cli_enlarge_reqbuf(req, DLM_INTENT_REC_OFF + 4,
261                                         body->eadatasize);
262         if (rc) {
263                 CERROR("Can't enlarge segment %d size to %d\n",
264                        DLM_INTENT_REC_OFF + 4, body->eadatasize);
265                 body->valid &= ~OBD_MD_FLEASIZE;
266                 body->eadatasize = 0;
267         }
268 }
269
270 static struct ptlrpc_request *mdc_intent_open_pack(struct obd_export *exp,
271                                                    struct lookup_intent *it,
272                                                    struct md_op_data *op_data,
273                                                    void *lmm, int lmmsize,
274                                                    void *cb_data)
275 {
276         struct ptlrpc_request *req;
277         struct obd_device     *obddev = class_exp2obd(exp);
278         struct ldlm_intent    *lit;
279         CFS_LIST_HEAD(cancels);
280         int                    count = 0;
281         int                    mode;
282         int                    rc;
283         ENTRY;
284
285         it->it_create_mode = (it->it_create_mode & ~S_IFMT) | S_IFREG;
286
287         /* XXX: openlock is not cancelled for cross-refs. */
288         /* If inode is known, cancel conflicting OPEN locks. */
289         if (fid_is_sane(&op_data->op_fid2)) {
290                 if (it->it_flags & (FMODE_WRITE|MDS_OPEN_TRUNC))
291                         mode = LCK_CW;
292 #ifdef FMODE_EXEC
293                 else if (it->it_flags & FMODE_EXEC)
294                         mode = LCK_PR;
295 #endif
296                 else
297                         mode = LCK_CR;
298                 count = mdc_resource_get_unused(exp, &op_data->op_fid2,
299                                                 &cancels, mode,
300                                                 MDS_INODELOCK_OPEN);
301         }
302
303         /* If CREATE, cancel parent's UPDATE lock. */
304         if (it->it_op & IT_CREAT)
305                 mode = LCK_EX;
306         else
307                 mode = LCK_CR;
308         count += mdc_resource_get_unused(exp, &op_data->op_fid1,
309                                          &cancels, mode,
310                                          MDS_INODELOCK_UPDATE);
311
312         req = ptlrpc_request_alloc(class_exp2cliimp(exp),
313                                    &RQF_LDLM_INTENT_OPEN);
314         if (req == NULL) {
315                 ldlm_lock_list_put(&cancels, l_bl_ast, count);
316                 RETURN(ERR_PTR(-ENOMEM));
317         }
318
319         /* parent capability */
320         mdc_set_capa_size(req, &RMF_CAPA1, op_data->op_capa1);
321         /* child capability, reserve the size according to parent capa, it will
322          * be filled after we get the reply */
323         mdc_set_capa_size(req, &RMF_CAPA2, op_data->op_capa1);
324
325         req_capsule_set_size(&req->rq_pill, &RMF_NAME, RCL_CLIENT,
326                              op_data->op_namelen + 1);
327         req_capsule_set_size(&req->rq_pill, &RMF_EADATA, RCL_CLIENT,
328                              max(lmmsize, obddev->u.cli.cl_default_mds_easize));
329
330         rc = ldlm_prep_enqueue_req(exp, req, &cancels, count);
331         if (rc) {
332                 ptlrpc_request_free(req);
333                 return NULL;
334         }
335
336         cfs_spin_lock(&req->rq_lock);
337         req->rq_replay = req->rq_import->imp_replayable;
338         cfs_spin_unlock(&req->rq_lock);
339
340         /* pack the intent */
341         lit = req_capsule_client_get(&req->rq_pill, &RMF_LDLM_INTENT);
342         lit->opc = (__u64)it->it_op;
343
344         /* pack the intended request */
345         mdc_open_pack(req, op_data, it->it_create_mode, 0, it->it_flags, lmm,
346                       lmmsize);
347
348         /* for remote client, fetch remote perm for current user */
349         if (client_is_remote(exp))
350                 req_capsule_set_size(&req->rq_pill, &RMF_ACL, RCL_SERVER,
351                                      sizeof(struct mdt_remote_perm));
352         ptlrpc_request_set_replen(req);
353         return req;
354 }
355
356 static struct ptlrpc_request *mdc_intent_unlink_pack(struct obd_export *exp,
357                                                      struct lookup_intent *it,
358                                                      struct md_op_data *op_data)
359 {
360         struct ptlrpc_request *req;
361         struct obd_device     *obddev = class_exp2obd(exp);
362         struct ldlm_intent    *lit;
363         int                    rc;
364         ENTRY;
365
366         req = ptlrpc_request_alloc(class_exp2cliimp(exp),
367                                    &RQF_LDLM_INTENT_UNLINK);
368         if (req == NULL)
369                 RETURN(ERR_PTR(-ENOMEM));
370
371         mdc_set_capa_size(req, &RMF_CAPA1, op_data->op_capa1);
372         req_capsule_set_size(&req->rq_pill, &RMF_NAME, RCL_CLIENT,
373                              op_data->op_namelen + 1);
374
375         rc = ldlm_prep_enqueue_req(exp, req, NULL, 0);
376         if (rc) {
377                 ptlrpc_request_free(req);
378                 RETURN(ERR_PTR(rc));
379         }
380
381         /* pack the intent */
382         lit = req_capsule_client_get(&req->rq_pill, &RMF_LDLM_INTENT);
383         lit->opc = (__u64)it->it_op;
384
385         /* pack the intended request */
386         mdc_unlink_pack(req, op_data);
387
388         req_capsule_set_size(&req->rq_pill, &RMF_MDT_MD, RCL_SERVER,
389                              obddev->u.cli.cl_max_mds_easize);
390         req_capsule_set_size(&req->rq_pill, &RMF_ACL, RCL_SERVER,
391                              obddev->u.cli.cl_max_mds_cookiesize);
392         ptlrpc_request_set_replen(req);
393         RETURN(req);
394 }
395
396 static struct ptlrpc_request *mdc_intent_getattr_pack(struct obd_export *exp,
397                                                       struct lookup_intent *it,
398                                                       struct md_op_data *op_data)
399 {
400         struct ptlrpc_request *req;
401         struct obd_device     *obddev = class_exp2obd(exp);
402         obd_valid              valid = OBD_MD_FLGETATTR | OBD_MD_FLEASIZE |
403                                        OBD_MD_FLMODEASIZE | OBD_MD_FLDIREA |
404                                        OBD_MD_FLMDSCAPA | OBD_MD_MEA |
405                                        (client_is_remote(exp) ?
406                                                OBD_MD_FLRMTPERM : OBD_MD_FLACL);
407         struct ldlm_intent    *lit;
408         int                    rc;
409         ENTRY;
410
411         req = ptlrpc_request_alloc(class_exp2cliimp(exp),
412                                    &RQF_LDLM_INTENT_GETATTR);
413         if (req == NULL)
414                 RETURN(ERR_PTR(-ENOMEM));
415
416         mdc_set_capa_size(req, &RMF_CAPA1, op_data->op_capa1);
417         req_capsule_set_size(&req->rq_pill, &RMF_NAME, RCL_CLIENT,
418                              op_data->op_namelen + 1);
419
420         rc = ldlm_prep_enqueue_req(exp, req, NULL, 0);
421         if (rc) {
422                 ptlrpc_request_free(req);
423                 RETURN(ERR_PTR(rc));
424         }
425
426         /* pack the intent */
427         lit = req_capsule_client_get(&req->rq_pill, &RMF_LDLM_INTENT);
428         lit->opc = (__u64)it->it_op;
429
430         /* pack the intended request */
431         mdc_getattr_pack(req, valid, it->it_flags, op_data,
432                          obddev->u.cli.cl_max_mds_easize);
433
434         req_capsule_set_size(&req->rq_pill, &RMF_MDT_MD, RCL_SERVER,
435                              obddev->u.cli.cl_max_mds_easize);
436         if (client_is_remote(exp))
437                 req_capsule_set_size(&req->rq_pill, &RMF_ACL, RCL_SERVER,
438                                      sizeof(struct mdt_remote_perm));
439         ptlrpc_request_set_replen(req);
440         RETURN(req);
441 }
442
443 static struct ptlrpc_request *ldlm_enqueue_pack(struct obd_export *exp)
444 {
445         struct ptlrpc_request *req;
446         int rc;
447         ENTRY;
448
449         req = ptlrpc_request_alloc(class_exp2cliimp(exp), &RQF_LDLM_ENQUEUE);
450         if (req == NULL)
451                 RETURN(ERR_PTR(-ENOMEM));
452
453         rc = ldlm_prep_enqueue_req(exp, req, NULL, 0);
454         if (rc) {
455                 ptlrpc_request_free(req);
456                 RETURN(ERR_PTR(rc));
457         }
458
459         ptlrpc_request_set_replen(req);
460         RETURN(req);
461 }
462
463 static int mdc_finish_enqueue(struct obd_export *exp,
464                               struct ptlrpc_request *req,
465                               struct ldlm_enqueue_info *einfo,
466                               struct lookup_intent *it,
467                               struct lustre_handle *lockh,
468                               int rc)
469 {
470         struct req_capsule  *pill = &req->rq_pill;
471         struct ldlm_request *lockreq;
472         struct ldlm_reply   *lockrep;
473         ENTRY;
474
475         LASSERT(rc >= 0);
476         /* Similarly, if we're going to replay this request, we don't want to
477          * actually get a lock, just perform the intent. */
478         if (req->rq_transno || req->rq_replay) {
479                 lockreq = req_capsule_client_get(pill, &RMF_DLM_REQ);
480                 lockreq->lock_flags |= LDLM_FL_INTENT_ONLY;
481         }
482
483         if (rc == ELDLM_LOCK_ABORTED) {
484                 einfo->ei_mode = 0;
485                 memset(lockh, 0, sizeof(*lockh));
486                 rc = 0;
487         } else { /* rc = 0 */
488                 struct ldlm_lock *lock = ldlm_handle2lock(lockh);
489                 LASSERT(lock);
490
491                 /* If the server gave us back a different lock mode, we should
492                  * fix up our variables. */
493                 if (lock->l_req_mode != einfo->ei_mode) {
494                         ldlm_lock_addref(lockh, lock->l_req_mode);
495                         ldlm_lock_decref(lockh, einfo->ei_mode);
496                         einfo->ei_mode = lock->l_req_mode;
497                 }
498                 LDLM_LOCK_PUT(lock);
499         }
500
501         lockrep = req_capsule_server_get(pill, &RMF_DLM_REP);
502         LASSERT(lockrep != NULL);                 /* checked by ldlm_cli_enqueue() */
503
504         it->d.lustre.it_disposition = (int)lockrep->lock_policy_res1;
505         it->d.lustre.it_status = (int)lockrep->lock_policy_res2;
506         it->d.lustre.it_lock_mode = einfo->ei_mode;
507         it->d.lustre.it_lock_handle = lockh->cookie;
508         it->d.lustre.it_data = req;
509
510         if (it->d.lustre.it_status < 0 && req->rq_replay)
511                 mdc_clear_replay_flag(req, it->d.lustre.it_status);
512
513         /* If we're doing an IT_OPEN which did not result in an actual
514          * successful open, then we need to remove the bit which saves
515          * this request for unconditional replay.
516          *
517          * It's important that we do this first!  Otherwise we might exit the
518          * function without doing so, and try to replay a failed create
519          * (bug 3440) */
520         if (it->it_op & IT_OPEN && req->rq_replay &&
521             (!it_disposition(it, DISP_OPEN_OPEN) ||it->d.lustre.it_status != 0))
522                 mdc_clear_replay_flag(req, it->d.lustre.it_status);
523
524         DEBUG_REQ(D_RPCTRACE, req, "op: %d disposition: %x, status: %d",
525                   it->it_op,it->d.lustre.it_disposition,it->d.lustre.it_status);
526
527         /* We know what to expect, so we do any byte flipping required here */
528         if (it->it_op & (IT_OPEN | IT_UNLINK | IT_LOOKUP | IT_GETATTR)) {
529                 struct mdt_body *body;
530
531                 body = req_capsule_server_get(pill, &RMF_MDT_BODY);
532                 if (body == NULL) {
533                         CERROR ("Can't swab mdt_body\n");
534                         RETURN (-EPROTO);
535                 }
536
537                 if (it_disposition(it, DISP_OPEN_OPEN) &&
538                     !it_open_error(DISP_OPEN_OPEN, it)) {
539                         /*
540                          * If this is a successful OPEN request, we need to set
541                          * replay handler and data early, so that if replay
542                          * happens immediately after swabbing below, new reply
543                          * is swabbed by that handler correctly.
544                          */
545                         mdc_set_open_replay_data(NULL, NULL, req);
546                 }
547
548                 if ((body->valid & (OBD_MD_FLDIREA | OBD_MD_FLEASIZE)) != 0) {
549                         void *eadata;
550
551                          mdc_update_max_ea_from_body(exp, body);
552
553                         /*
554                          * The eadata is opaque; just check that it is there.
555                          * Eventually, obd_unpackmd() will check the contents.
556                          */
557                         eadata = req_capsule_server_sized_get(pill, &RMF_MDT_MD,
558                                                               body->eadatasize);
559                         if (eadata == NULL)
560                                 RETURN(-EPROTO);
561
562                         /*
563                          * We save the reply LOV EA in case we have to replay a
564                          * create for recovery.  If we didn't allocate a large
565                          * enough request buffer above we need to reallocate it
566                          * here to hold the actual LOV EA.
567                          *
568                          * To not save LOV EA if request is not going to replay
569                          * (for example error one).
570                          */
571                         if ((it->it_op & IT_OPEN) && req->rq_replay) {
572                                 void *lmm;
573                                 if (req_capsule_get_size(pill, &RMF_EADATA,
574                                                          RCL_CLIENT) <
575                                     body->eadatasize)
576                                         mdc_realloc_openmsg(req, body);
577                                 else
578                                         req_capsule_shrink(pill, &RMF_EADATA,
579                                                            body->eadatasize,
580                                                            RCL_CLIENT);
581
582                                 req_capsule_set_size(pill, &RMF_EADATA,
583                                                      RCL_CLIENT,
584                                                      body->eadatasize);
585
586                                 lmm = req_capsule_client_get(pill, &RMF_EADATA);
587                                 if (lmm)
588                                         memcpy(lmm, eadata, body->eadatasize);
589                         }
590                 }
591
592                 if (body->valid & OBD_MD_FLRMTPERM) {
593                         struct mdt_remote_perm *perm;
594
595                         LASSERT(client_is_remote(exp));
596                         perm = req_capsule_server_swab_get(pill, &RMF_ACL,
597                                                 lustre_swab_mdt_remote_perm);
598                         if (perm == NULL)
599                                 RETURN(-EPROTO);
600                 }
601                 if (body->valid & OBD_MD_FLMDSCAPA) {
602                         struct lustre_capa *capa, *p;
603
604                         capa = req_capsule_server_get(pill, &RMF_CAPA1);
605                         if (capa == NULL)
606                                 RETURN(-EPROTO);
607
608                         if (it->it_op & IT_OPEN) {
609                                 /* client fid capa will be checked in replay */
610                                 p = req_capsule_client_get(pill, &RMF_CAPA2);
611                                 LASSERT(p);
612                                 *p = *capa;
613                         }
614                 }
615                 if (body->valid & OBD_MD_FLOSSCAPA) {
616                         struct lustre_capa *capa;
617
618                         capa = req_capsule_server_get(pill, &RMF_CAPA2);
619                         if (capa == NULL)
620                                 RETURN(-EPROTO);
621                 }
622         }
623
624         RETURN(rc);
625 }
626
627 /* We always reserve enough space in the reply packet for a stripe MD, because
628  * we don't know in advance the file type. */
629 int mdc_enqueue(struct obd_export *exp, struct ldlm_enqueue_info *einfo,
630                 struct lookup_intent *it, struct md_op_data *op_data,
631                 struct lustre_handle *lockh, void *lmm, int lmmsize,
632                 struct ptlrpc_request **reqp, int extra_lock_flags)
633 {
634         struct obd_device     *obddev = class_exp2obd(exp);
635         struct ptlrpc_request *req = NULL;
636         int                    flags = extra_lock_flags;
637         int                    rc;
638         struct ldlm_res_id res_id;
639         static const ldlm_policy_data_t lookup_policy =
640                             { .l_inodebits = { MDS_INODELOCK_LOOKUP } };
641         static const ldlm_policy_data_t update_policy =
642                             { .l_inodebits = { MDS_INODELOCK_UPDATE } };
643         ldlm_policy_data_t const *policy = &lookup_policy;
644         ENTRY;
645
646         LASSERTF(!it || einfo->ei_type == LDLM_IBITS, "lock type %d\n",
647                  einfo->ei_type);
648
649         fid_build_reg_res_name(&op_data->op_fid1, &res_id);
650
651         if (it)
652                 flags |= LDLM_FL_HAS_INTENT;
653         if (it && it->it_op & (IT_UNLINK | IT_GETATTR | IT_READDIR))
654                 policy = &update_policy;
655
656         if (reqp)
657                 req = *reqp;
658
659         if (!it) {
660                 /* The only way right now is FLOCK, in this case we hide flock
661                    policy as lmm, but lmmsize is 0 */
662                 LASSERT(lmm && lmmsize == 0);
663                 LASSERTF(einfo->ei_type == LDLM_FLOCK, "lock type %d\n",
664                          einfo->ei_type);
665                 policy = (ldlm_policy_data_t *)lmm;
666                 res_id.name[3] = LDLM_FLOCK;
667         } else if (it->it_op & IT_OPEN) {
668                 req = mdc_intent_open_pack(exp, it, op_data, lmm, lmmsize,
669                                            einfo->ei_cbdata);
670                 policy = &update_policy;
671                 einfo->ei_cbdata = NULL;
672                 lmm = NULL;
673         } else if (it->it_op & IT_UNLINK)
674                 req = mdc_intent_unlink_pack(exp, it, op_data);
675         else if (it->it_op & (IT_GETATTR | IT_LOOKUP | IT_LAYOUT))
676                 req = mdc_intent_getattr_pack(exp, it, op_data);
677         else if (it->it_op == IT_READDIR)
678                 req = ldlm_enqueue_pack(exp);
679         else {
680                 LBUG();
681                 RETURN(-EINVAL);
682         }
683
684         if (IS_ERR(req))
685                 RETURN(PTR_ERR(req));
686
687         /* It is important to obtain rpc_lock first (if applicable), so that
688          * threads that are serialised with rpc_lock are not polluting our
689          * rpcs in flight counter. We do not do flock request limiting, though*/
690         if (it) {
691                 mdc_get_rpc_lock(obddev->u.cli.cl_rpc_lock, it);
692                 rc = mdc_enter_request(&obddev->u.cli);
693                 if (rc != 0) {
694                         mdc_put_rpc_lock(obddev->u.cli.cl_rpc_lock, it);
695                         mdc_clear_replay_flag(req, 0);
696                         ptlrpc_req_finished(req);
697                         RETURN(rc);
698                 }
699         }
700
701         rc = ldlm_cli_enqueue(exp, &req, einfo, &res_id, policy, &flags, NULL,
702                               0, lockh, 0);
703         if (reqp)
704                 *reqp = req;
705
706         if (it) {
707                 mdc_exit_request(&obddev->u.cli);
708                 mdc_put_rpc_lock(obddev->u.cli.cl_rpc_lock, it);
709         }
710         if (!it) {
711                 /* For flock requests we immediatelly return without further
712                    delay and let caller deal with the rest, since rest of
713                    this function metadata processing makes no sense for flock
714                    requests anyway */
715                 RETURN(rc);
716         }
717
718         if (rc < 0) {
719                 CERROR("ldlm_cli_enqueue: %d\n", rc);
720                 mdc_clear_replay_flag(req, rc);
721                 ptlrpc_req_finished(req);
722                 RETURN(rc);
723         }
724         rc = mdc_finish_enqueue(exp, req, einfo, it, lockh, rc);
725
726         RETURN(rc);
727 }
728
729 static int mdc_finish_intent_lock(struct obd_export *exp,
730                                   struct ptlrpc_request *request,
731                                   struct md_op_data *op_data,
732                                   struct lookup_intent *it,
733                                   struct lustre_handle *lockh)
734 {
735         struct lustre_handle old_lock;
736         struct mdt_body *mdt_body;
737         struct ldlm_lock *lock;
738         int rc;
739
740
741         LASSERT(request != NULL);
742         LASSERT(request != LP_POISON);
743         LASSERT(request->rq_repmsg != LP_POISON);
744
745         if (!it_disposition(it, DISP_IT_EXECD)) {
746                 /* The server failed before it even started executing the
747                  * intent, i.e. because it couldn't unpack the request. */
748                 LASSERT(it->d.lustre.it_status != 0);
749                 RETURN(it->d.lustre.it_status);
750         }
751         rc = it_open_error(DISP_IT_EXECD, it);
752         if (rc)
753                 RETURN(rc);
754
755         mdt_body = req_capsule_server_get(&request->rq_pill, &RMF_MDT_BODY);
756         LASSERT(mdt_body != NULL);      /* mdc_enqueue checked */
757
758         /* If we were revalidating a fid/name pair, mark the intent in
759          * case we fail and get called again from lookup */
760         if (fid_is_sane(&op_data->op_fid2) &&
761             it->it_create_mode & M_CHECK_STALE &&
762             it->it_op != IT_GETATTR) {
763                 it_set_disposition(it, DISP_ENQ_COMPLETE);
764
765                 /* Also: did we find the same inode? */
766                 /* sever can return one of two fids:
767                  * op_fid2 - new allocated fid - if file is created.
768                  * op_fid3 - existent fid - if file only open.
769                  * op_fid3 is saved in lmv_intent_open */
770                 if ((!lu_fid_eq(&op_data->op_fid2, &mdt_body->fid1)) &&
771                     (!lu_fid_eq(&op_data->op_fid3, &mdt_body->fid1))) {
772                         CDEBUG(D_DENTRY, "Found stale data "DFID"("DFID")/"DFID
773                                "\n", PFID(&op_data->op_fid2),
774                                PFID(&op_data->op_fid2), PFID(&mdt_body->fid1));
775                         RETURN(-ESTALE);
776                 }
777         }
778
779         rc = it_open_error(DISP_LOOKUP_EXECD, it);
780         if (rc)
781                 RETURN(rc);
782
783         /* keep requests around for the multiple phases of the call
784          * this shows the DISP_XX must guarantee we make it into the call
785          */
786         if (!it_disposition(it, DISP_ENQ_CREATE_REF) &&
787             it_disposition(it, DISP_OPEN_CREATE) &&
788             !it_open_error(DISP_OPEN_CREATE, it)) {
789                 it_set_disposition(it, DISP_ENQ_CREATE_REF);
790                 ptlrpc_request_addref(request); /* balanced in ll_create_node */
791         }
792         if (!it_disposition(it, DISP_ENQ_OPEN_REF) &&
793             it_disposition(it, DISP_OPEN_OPEN) &&
794             !it_open_error(DISP_OPEN_OPEN, it)) {
795                 it_set_disposition(it, DISP_ENQ_OPEN_REF);
796                 ptlrpc_request_addref(request); /* balanced in ll_file_open */
797                 /* BUG 11546 - eviction in the middle of open rpc processing */
798                 OBD_FAIL_TIMEOUT(OBD_FAIL_MDC_ENQUEUE_PAUSE, obd_timeout);
799         }
800
801         if (it->it_op & IT_CREAT) {
802                 /* XXX this belongs in ll_create_it */
803         } else if (it->it_op == IT_OPEN) {
804                 LASSERT(!it_disposition(it, DISP_OPEN_CREATE));
805         } else {
806                 LASSERT(it->it_op & (IT_GETATTR | IT_LOOKUP | IT_LAYOUT));
807         }
808
809         /* If we already have a matching lock, then cancel the new
810          * one.  We have to set the data here instead of in
811          * mdc_enqueue, because we need to use the child's inode as
812          * the l_ast_data to match, and that's not available until
813          * intent_finish has performed the iget().) */
814         lock = ldlm_handle2lock(lockh);
815         if (lock) {
816                 ldlm_policy_data_t policy = lock->l_policy_data;
817                 LDLM_DEBUG(lock, "matching against this");
818
819                 LASSERTF(fid_res_name_eq(&mdt_body->fid1,
820                                          &lock->l_resource->lr_name),
821                          "Lock res_id: %lu/%lu/%lu, fid: %lu/%lu/%lu.\n",
822                          (unsigned long)lock->l_resource->lr_name.name[0],
823                          (unsigned long)lock->l_resource->lr_name.name[1],
824                          (unsigned long)lock->l_resource->lr_name.name[2],
825                          (unsigned long)fid_seq(&mdt_body->fid1),
826                          (unsigned long)fid_oid(&mdt_body->fid1),
827                          (unsigned long)fid_ver(&mdt_body->fid1));
828                 LDLM_LOCK_PUT(lock);
829
830                 memcpy(&old_lock, lockh, sizeof(*lockh));
831                 if (ldlm_lock_match(NULL, LDLM_FL_BLOCK_GRANTED, NULL,
832                                     LDLM_IBITS, &policy, LCK_NL, &old_lock, 0)) {
833                         ldlm_lock_decref_and_cancel(lockh,
834                                                     it->d.lustre.it_lock_mode);
835                         memcpy(lockh, &old_lock, sizeof(old_lock));
836                         it->d.lustre.it_lock_handle = lockh->cookie;
837                 }
838         }
839         CDEBUG(D_DENTRY,"D_IT dentry %.*s intent: %s status %d disp %x rc %d\n",
840                op_data->op_namelen, op_data->op_name, ldlm_it2str(it->it_op),
841                it->d.lustre.it_status, it->d.lustre.it_disposition, rc);
842         RETURN(rc);
843 }
844
845 int mdc_revalidate_lock(struct obd_export *exp, struct lookup_intent *it,
846                         struct lu_fid *fid, __u64 *bits)
847 {
848         /* We could just return 1 immediately, but since we should only
849          * be called in revalidate_it if we already have a lock, let's
850          * verify that. */
851         struct ldlm_res_id res_id;
852         struct lustre_handle lockh;
853         ldlm_policy_data_t policy;
854         ldlm_mode_t mode;
855         ENTRY;
856
857         if (it->d.lustre.it_lock_handle) {
858                 lockh.cookie = it->d.lustre.it_lock_handle;
859                 mode = ldlm_revalidate_lock_handle(&lockh, bits);
860         } else {
861                 fid_build_reg_res_name(fid, &res_id);
862                 switch (it->it_op) {
863                 case IT_GETATTR:
864                         policy.l_inodebits.bits = MDS_INODELOCK_UPDATE;
865                         break;
866                 case IT_LAYOUT:
867                         policy.l_inodebits.bits = MDS_INODELOCK_LAYOUT;
868                         break;
869                 default:
870                         policy.l_inodebits.bits = MDS_INODELOCK_LOOKUP;
871                         break;
872                 }
873                 mode = ldlm_lock_match(exp->exp_obd->obd_namespace,
874                                        LDLM_FL_BLOCK_GRANTED, &res_id,
875                                        LDLM_IBITS, &policy,
876                                        LCK_CR|LCK_CW|LCK_PR|LCK_PW, &lockh, 0);
877         }
878
879         if (mode) {
880                 it->d.lustre.it_lock_handle = lockh.cookie;
881                 it->d.lustre.it_lock_mode = mode;
882         } else {
883                 it->d.lustre.it_lock_handle = 0;
884                 it->d.lustre.it_lock_mode = 0;
885         }
886
887         RETURN(!!mode);
888 }
889
890 /*
891  * This long block is all about fixing up the lock and request state
892  * so that it is correct as of the moment _before_ the operation was
893  * applied; that way, the VFS will think that everything is normal and
894  * call Lustre's regular VFS methods.
895  *
896  * If we're performing a creation, that means that unless the creation
897  * failed with EEXIST, we should fake up a negative dentry.
898  *
899  * For everything else, we want to lookup to succeed.
900  *
901  * One additional note: if CREATE or OPEN succeeded, we add an extra
902  * reference to the request because we need to keep it around until
903  * ll_create/ll_open gets called.
904  *
905  * The server will return to us, in it_disposition, an indication of
906  * exactly what d.lustre.it_status refers to.
907  *
908  * If DISP_OPEN_OPEN is set, then d.lustre.it_status refers to the open() call,
909  * otherwise if DISP_OPEN_CREATE is set, then it status is the
910  * creation failure mode.  In either case, one of DISP_LOOKUP_NEG or
911  * DISP_LOOKUP_POS will be set, indicating whether the child lookup
912  * was successful.
913  *
914  * Else, if DISP_LOOKUP_EXECD then d.lustre.it_status is the rc of the
915  * child lookup.
916  */
917 int mdc_intent_lock(struct obd_export *exp, struct md_op_data *op_data,
918                     void *lmm, int lmmsize, struct lookup_intent *it,
919                     int lookup_flags, struct ptlrpc_request **reqp,
920                     ldlm_blocking_callback cb_blocking,
921                     int extra_lock_flags)
922 {
923         struct lustre_handle lockh;
924         int rc = 0;
925         ENTRY;
926         LASSERT(it);
927
928         CDEBUG(D_DLMTRACE, "(name: %.*s,"DFID") in obj "DFID
929                ", intent: %s flags %#o\n", op_data->op_namelen,
930                op_data->op_name, PFID(&op_data->op_fid2),
931                PFID(&op_data->op_fid1), ldlm_it2str(it->it_op),
932                it->it_flags);
933
934         lockh.cookie = 0;
935         if (fid_is_sane(&op_data->op_fid2) &&
936             (it->it_op & (IT_LOOKUP | IT_GETATTR | IT_LAYOUT))) {
937                 /* We could just return 1 immediately, but since we should only
938                  * be called in revalidate_it if we already have a lock, let's
939                  * verify that. */
940                 it->d.lustre.it_lock_handle = 0;
941                 rc = mdc_revalidate_lock(exp, it, &op_data->op_fid2, NULL);
942                 /* Only return failure if it was not GETATTR by cfid
943                    (from inode_revalidate) */
944                 if (rc || op_data->op_namelen != 0)
945                         RETURN(rc);
946         }
947
948         /* lookup_it may be called only after revalidate_it has run, because
949          * revalidate_it cannot return errors, only zero.  Returning zero causes
950          * this call to lookup, which *can* return an error.
951          *
952          * We only want to execute the request associated with the intent one
953          * time, however, so don't send the request again.  Instead, skip past
954          * this and use the request from revalidate.  In this case, revalidate
955          * never dropped its reference, so the refcounts are all OK */
956         if (!it_disposition(it, DISP_ENQ_COMPLETE)) {
957                 struct ldlm_enqueue_info einfo =
958                         { LDLM_IBITS, it_to_lock_mode(it), cb_blocking,
959                           ldlm_completion_ast, NULL, NULL, NULL };
960
961                 /* For case if upper layer did not alloc fid, do it now. */
962                 if (!fid_is_sane(&op_data->op_fid2) && it->it_op & IT_CREAT) {
963                         rc = mdc_fid_alloc(exp, &op_data->op_fid2, op_data);
964                         if (rc < 0) {
965                                 CERROR("Can't alloc new fid, rc %d\n", rc);
966                                 RETURN(rc);
967                         }
968                 }
969                 rc = mdc_enqueue(exp, &einfo, it, op_data, &lockh,
970                                  lmm, lmmsize, NULL, extra_lock_flags);
971                 if (rc < 0)
972                         RETURN(rc);
973         } else if (!fid_is_sane(&op_data->op_fid2) ||
974                    !(it->it_create_mode & M_CHECK_STALE)) {
975                 /* DISP_ENQ_COMPLETE set means there is extra reference on
976                  * request referenced from this intent, saved for subsequent
977                  * lookup.  This path is executed when we proceed to this
978                  * lookup, so we clear DISP_ENQ_COMPLETE */
979                 it_clear_disposition(it, DISP_ENQ_COMPLETE);
980         }
981         *reqp = it->d.lustre.it_data;
982         rc = mdc_finish_intent_lock(exp, *reqp, op_data, it, &lockh);
983         RETURN(rc);
984 }
985
986 static int mdc_intent_getattr_async_interpret(const struct lu_env *env,
987                                               struct ptlrpc_request *req,
988                                               void *args, int rc)
989 {
990         struct mdc_getattr_args  *ga = args;
991         struct obd_export        *exp = ga->ga_exp;
992         struct md_enqueue_info   *minfo = ga->ga_minfo;
993         struct ldlm_enqueue_info *einfo = ga->ga_einfo;
994         struct lookup_intent     *it;
995         struct lustre_handle     *lockh;
996         struct obd_device        *obddev;
997         int                       flags = LDLM_FL_HAS_INTENT;
998         ENTRY;
999
1000         it    = &minfo->mi_it;
1001         lockh = &minfo->mi_lockh;
1002
1003         obddev = class_exp2obd(exp);
1004
1005         mdc_exit_request(&obddev->u.cli);
1006         if (OBD_FAIL_CHECK(OBD_FAIL_MDC_GETATTR_ENQUEUE))
1007                 rc = -ETIMEDOUT;
1008
1009         rc = ldlm_cli_enqueue_fini(exp, req, einfo->ei_type, 1, einfo->ei_mode,
1010                                    &flags, NULL, 0, lockh, rc);
1011         if (rc < 0) {
1012                 CERROR("ldlm_cli_enqueue_fini: %d\n", rc);
1013                 mdc_clear_replay_flag(req, rc);
1014                 GOTO(out, rc);
1015         }
1016
1017         rc = mdc_finish_enqueue(exp, req, einfo, it, lockh, rc);
1018         if (rc)
1019                 GOTO(out, rc);
1020
1021         rc = mdc_finish_intent_lock(exp, req, &minfo->mi_data, it, lockh);
1022         EXIT;
1023
1024 out:
1025         OBD_FREE_PTR(einfo);
1026         minfo->mi_cb(req, minfo, rc);
1027         return 0;
1028 }
1029
1030 int mdc_intent_getattr_async(struct obd_export *exp,
1031                              struct md_enqueue_info *minfo,
1032                              struct ldlm_enqueue_info *einfo)
1033 {
1034         struct md_op_data       *op_data = &minfo->mi_data;
1035         struct lookup_intent    *it = &minfo->mi_it;
1036         struct ptlrpc_request   *req;
1037         struct mdc_getattr_args *ga;
1038         struct obd_device       *obddev = class_exp2obd(exp);
1039         struct ldlm_res_id       res_id;
1040         /*XXX: Both MDS_INODELOCK_LOOKUP and MDS_INODELOCK_UPDATE are needed
1041          *     for statahead currently. Consider CMD in future, such two bits
1042          *     maybe managed by different MDS, should be adjusted then. */
1043         ldlm_policy_data_t       policy = {
1044                                         .l_inodebits = { MDS_INODELOCK_LOOKUP | 
1045                                                          MDS_INODELOCK_UPDATE }
1046                                  };
1047         int                      rc = 0;
1048         int                      flags = LDLM_FL_HAS_INTENT;
1049         ENTRY;
1050
1051         CDEBUG(D_DLMTRACE,"name: %.*s in inode "DFID", intent: %s flags %#o\n",
1052                op_data->op_namelen, op_data->op_name, PFID(&op_data->op_fid1),
1053                ldlm_it2str(it->it_op), it->it_flags);
1054
1055         fid_build_reg_res_name(&op_data->op_fid1, &res_id);
1056         req = mdc_intent_getattr_pack(exp, it, op_data);
1057         if (!req)
1058                 RETURN(-ENOMEM);
1059
1060         rc = mdc_enter_request(&obddev->u.cli);
1061         if (rc != 0) {
1062                 ptlrpc_req_finished(req);
1063                 RETURN(rc);
1064         }
1065
1066         rc = ldlm_cli_enqueue(exp, &req, einfo, &res_id, &policy, &flags, NULL,
1067                               0, &minfo->mi_lockh, 1);
1068         if (rc < 0) {
1069                 mdc_exit_request(&obddev->u.cli);
1070                 ptlrpc_req_finished(req);
1071                 RETURN(rc);
1072         }
1073
1074         CLASSERT(sizeof(*ga) <= sizeof(req->rq_async_args));
1075         ga = ptlrpc_req_async_args(req);
1076         ga->ga_exp = exp;
1077         ga->ga_minfo = minfo;
1078         ga->ga_einfo = einfo;
1079
1080         req->rq_interpret_reply = mdc_intent_getattr_async_interpret;
1081         ptlrpcd_add_req(req, PDL_POLICY_LOCAL, -1);
1082
1083         RETURN(0);
1084 }