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LU-1346 libcfs: replace libcfs wrappers with kernel API
[fs/lustre-release.git] / lustre / fld / fld_request.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) 2007, 2010, Oracle and/or its affiliates. All rights reserved.
28  * Use is subject to license terms.
29  *
30  * Copyright (c) 2011, Whamcloud, Inc.
31  */
32 /*
33  * This file is part of Lustre, http://www.lustre.org/
34  * Lustre is a trademark of Sun Microsystems, Inc.
35  *
36  * lustre/fld/fld_request.c
37  *
38  * FLD (Fids Location Database)
39  *
40  * Author: Yury Umanets <umka@clusterfs.com>
41  */
42
43 #define DEBUG_SUBSYSTEM S_FLD
44
45 #ifdef __KERNEL__
46 # include <libcfs/libcfs.h>
47 # include <linux/module.h>
48 # include <linux/jbd.h>
49 # include <asm/div64.h>
50 #else /* __KERNEL__ */
51 # include <liblustre.h>
52 # include <libcfs/list.h>
53 #endif
54
55 #include <obd.h>
56 #include <obd_class.h>
57 #include <lustre_ver.h>
58 #include <obd_support.h>
59 #include <lprocfs_status.h>
60
61 #include <dt_object.h>
62 #include <md_object.h>
63 #include <lustre_req_layout.h>
64 #include <lustre_fld.h>
65 #include <lustre_mdc.h>
66 #include "fld_internal.h"
67
68 /* TODO: these 3 functions are copies of flow-control code from mdc_lib.c
69  * It should be common thing. The same about mdc RPC lock */
70 static int fld_req_avail(struct client_obd *cli, struct mdc_cache_waiter *mcw)
71 {
72         int rc;
73         ENTRY;
74         client_obd_list_lock(&cli->cl_loi_list_lock);
75         rc = cfs_list_empty(&mcw->mcw_entry);
76         client_obd_list_unlock(&cli->cl_loi_list_lock);
77         RETURN(rc);
78 };
79
80 static void fld_enter_request(struct client_obd *cli)
81 {
82         struct mdc_cache_waiter mcw;
83         struct l_wait_info lwi = { 0 };
84
85         client_obd_list_lock(&cli->cl_loi_list_lock);
86         if (cli->cl_r_in_flight >= cli->cl_max_rpcs_in_flight) {
87                 cfs_list_add_tail(&mcw.mcw_entry, &cli->cl_cache_waiters);
88                 cfs_waitq_init(&mcw.mcw_waitq);
89                 client_obd_list_unlock(&cli->cl_loi_list_lock);
90                 l_wait_event(mcw.mcw_waitq, fld_req_avail(cli, &mcw), &lwi);
91         } else {
92                 cli->cl_r_in_flight++;
93                 client_obd_list_unlock(&cli->cl_loi_list_lock);
94         }
95 }
96
97 static void fld_exit_request(struct client_obd *cli)
98 {
99         cfs_list_t *l, *tmp;
100         struct mdc_cache_waiter *mcw;
101
102         client_obd_list_lock(&cli->cl_loi_list_lock);
103         cli->cl_r_in_flight--;
104         cfs_list_for_each_safe(l, tmp, &cli->cl_cache_waiters) {
105
106                 if (cli->cl_r_in_flight >= cli->cl_max_rpcs_in_flight) {
107                         /* No free request slots anymore */
108                         break;
109                 }
110
111                 mcw = cfs_list_entry(l, struct mdc_cache_waiter, mcw_entry);
112                 cfs_list_del_init(&mcw->mcw_entry);
113                 cli->cl_r_in_flight++;
114                 cfs_waitq_signal(&mcw->mcw_waitq);
115         }
116         client_obd_list_unlock(&cli->cl_loi_list_lock);
117 }
118
119 static int fld_rrb_hash(struct lu_client_fld *fld,
120                         seqno_t seq)
121 {
122         LASSERT(fld->lcf_count > 0);
123         return do_div(seq, fld->lcf_count);
124 }
125
126 static struct lu_fld_target *
127 fld_rrb_scan(struct lu_client_fld *fld, seqno_t seq)
128 {
129         struct lu_fld_target *target;
130         int hash;
131         ENTRY;
132
133         hash = fld_rrb_hash(fld, seq);
134
135         cfs_list_for_each_entry(target, &fld->lcf_targets, ft_chain) {
136                 if (target->ft_idx == hash)
137                         RETURN(target);
138         }
139
140         CERROR("%s: Can't find target by hash %d (seq "LPX64"). "
141                "Targets (%d):\n", fld->lcf_name, hash, seq,
142                fld->lcf_count);
143
144         cfs_list_for_each_entry(target, &fld->lcf_targets, ft_chain) {
145                 const char *srv_name = target->ft_srv != NULL  ?
146                         target->ft_srv->lsf_name : "<null>";
147                 const char *exp_name = target->ft_exp != NULL ?
148                         (char *)target->ft_exp->exp_obd->obd_uuid.uuid :
149                         "<null>";
150
151                 CERROR("  exp: 0x%p (%s), srv: 0x%p (%s), idx: "LPU64"\n",
152                        target->ft_exp, exp_name, target->ft_srv,
153                        srv_name, target->ft_idx);
154         }
155
156         /*
157          * If target is not found, there is logical error anyway, so here is
158          * LBUG() to catch this situation.
159          */
160         LBUG();
161         RETURN(NULL);
162 }
163
164 struct lu_fld_hash fld_hash[] = {
165         {
166                 .fh_name = "RRB",
167                 .fh_hash_func = fld_rrb_hash,
168                 .fh_scan_func = fld_rrb_scan
169         },
170         {
171                 0,
172         }
173 };
174
175 static struct lu_fld_target *
176 fld_client_get_target(struct lu_client_fld *fld, seqno_t seq)
177 {
178         struct lu_fld_target *target;
179         ENTRY;
180
181         LASSERT(fld->lcf_hash != NULL);
182
183         spin_lock(&fld->lcf_lock);
184         target = fld->lcf_hash->fh_scan_func(fld, seq);
185         spin_unlock(&fld->lcf_lock);
186
187         if (target != NULL) {
188                 CDEBUG(D_INFO, "%s: Found target (idx "LPU64
189                        ") by seq "LPX64"\n", fld->lcf_name,
190                        target->ft_idx, seq);
191         }
192
193         RETURN(target);
194 }
195
196 /*
197  * Add export to FLD. This is usually done by CMM and LMV as they are main users
198  * of FLD module.
199  */
200 int fld_client_add_target(struct lu_client_fld *fld,
201                           struct lu_fld_target *tar)
202 {
203         const char *name = fld_target_name(tar);
204         struct lu_fld_target *target, *tmp;
205         ENTRY;
206
207         LASSERT(tar != NULL);
208         LASSERT(name != NULL);
209         LASSERT(tar->ft_srv != NULL || tar->ft_exp != NULL);
210
211         if (fld->lcf_flags != LUSTRE_FLD_INIT) {
212                 CERROR("%s: Attempt to add target %s (idx "LPU64") "
213                        "on fly - skip it\n", fld->lcf_name, name,
214                        tar->ft_idx);
215                 RETURN(0);
216         } else {
217                 CDEBUG(D_INFO, "%s: Adding target %s (idx "
218                        LPU64")\n", fld->lcf_name, name, tar->ft_idx);
219         }
220
221         OBD_ALLOC_PTR(target);
222         if (target == NULL)
223                 RETURN(-ENOMEM);
224
225         spin_lock(&fld->lcf_lock);
226         cfs_list_for_each_entry(tmp, &fld->lcf_targets, ft_chain) {
227                 if (tmp->ft_idx == tar->ft_idx) {
228                         spin_unlock(&fld->lcf_lock);
229                         OBD_FREE_PTR(target);
230                         CERROR("Target %s exists in FLD and known as %s:#"LPU64"\n",
231                                name, fld_target_name(tmp), tmp->ft_idx);
232                         RETURN(-EEXIST);
233                 }
234         }
235
236         target->ft_exp = tar->ft_exp;
237         if (target->ft_exp != NULL)
238                 class_export_get(target->ft_exp);
239         target->ft_srv = tar->ft_srv;
240         target->ft_idx = tar->ft_idx;
241
242         cfs_list_add_tail(&target->ft_chain,
243                           &fld->lcf_targets);
244
245         fld->lcf_count++;
246         spin_unlock(&fld->lcf_lock);
247
248         RETURN(0);
249 }
250 EXPORT_SYMBOL(fld_client_add_target);
251
252 /* Remove export from FLD */
253 int fld_client_del_target(struct lu_client_fld *fld, __u64 idx)
254 {
255         struct lu_fld_target *target, *tmp;
256         ENTRY;
257
258         spin_lock(&fld->lcf_lock);
259         cfs_list_for_each_entry_safe(target, tmp,
260                                      &fld->lcf_targets, ft_chain) {
261                 if (target->ft_idx == idx) {
262                         fld->lcf_count--;
263                         cfs_list_del(&target->ft_chain);
264                         spin_unlock(&fld->lcf_lock);
265
266                         if (target->ft_exp != NULL)
267                                 class_export_put(target->ft_exp);
268
269                         OBD_FREE_PTR(target);
270                         RETURN(0);
271                 }
272         }
273         spin_unlock(&fld->lcf_lock);
274         RETURN(-ENOENT);
275 }
276 EXPORT_SYMBOL(fld_client_del_target);
277
278 #ifdef LPROCFS
279 static int fld_client_proc_init(struct lu_client_fld *fld)
280 {
281         int rc;
282         ENTRY;
283
284         fld->lcf_proc_dir = lprocfs_register(fld->lcf_name,
285                                              fld_type_proc_dir,
286                                              NULL, NULL);
287
288         if (IS_ERR(fld->lcf_proc_dir)) {
289                 CERROR("%s: LProcFS failed in fld-init\n",
290                        fld->lcf_name);
291                 rc = PTR_ERR(fld->lcf_proc_dir);
292                 RETURN(rc);
293         }
294
295         rc = lprocfs_add_vars(fld->lcf_proc_dir,
296                               fld_client_proc_list, fld);
297         if (rc) {
298                 CERROR("%s: Can't init FLD proc, rc %d\n",
299                        fld->lcf_name, rc);
300                 GOTO(out_cleanup, rc);
301         }
302
303         RETURN(0);
304
305 out_cleanup:
306         fld_client_proc_fini(fld);
307         return rc;
308 }
309
310 void fld_client_proc_fini(struct lu_client_fld *fld)
311 {
312         ENTRY;
313         if (fld->lcf_proc_dir) {
314                 if (!IS_ERR(fld->lcf_proc_dir))
315                         lprocfs_remove(&fld->lcf_proc_dir);
316                 fld->lcf_proc_dir = NULL;
317         }
318         EXIT;
319 }
320 #else
321 static int fld_client_proc_init(struct lu_client_fld *fld)
322 {
323         return 0;
324 }
325
326 void fld_client_proc_fini(struct lu_client_fld *fld)
327 {
328         return;
329 }
330 #endif
331
332 EXPORT_SYMBOL(fld_client_proc_fini);
333
334 static inline int hash_is_sane(int hash)
335 {
336         return (hash >= 0 && hash < ARRAY_SIZE(fld_hash));
337 }
338
339 int fld_client_init(struct lu_client_fld *fld,
340                     const char *prefix, int hash)
341 {
342         int cache_size, cache_threshold;
343         int rc;
344         ENTRY;
345
346         LASSERT(fld != NULL);
347
348         snprintf(fld->lcf_name, sizeof(fld->lcf_name),
349                  "cli-%s", prefix);
350
351         if (!hash_is_sane(hash)) {
352                 CERROR("%s: Wrong hash function %#x\n",
353                        fld->lcf_name, hash);
354                 RETURN(-EINVAL);
355         }
356
357         fld->lcf_count = 0;
358         spin_lock_init(&fld->lcf_lock);
359         fld->lcf_hash = &fld_hash[hash];
360         fld->lcf_flags = LUSTRE_FLD_INIT;
361         CFS_INIT_LIST_HEAD(&fld->lcf_targets);
362
363         cache_size = FLD_CLIENT_CACHE_SIZE /
364                 sizeof(struct fld_cache_entry);
365
366         cache_threshold = cache_size *
367                 FLD_CLIENT_CACHE_THRESHOLD / 100;
368
369         fld->lcf_cache = fld_cache_init(fld->lcf_name,
370                                         cache_size, cache_threshold);
371         if (IS_ERR(fld->lcf_cache)) {
372                 rc = PTR_ERR(fld->lcf_cache);
373                 fld->lcf_cache = NULL;
374                 GOTO(out, rc);
375         }
376
377         rc = fld_client_proc_init(fld);
378         if (rc)
379                 GOTO(out, rc);
380         EXIT;
381 out:
382         if (rc)
383                 fld_client_fini(fld);
384         else
385                 CDEBUG(D_INFO, "%s: Using \"%s\" hash\n",
386                        fld->lcf_name, fld->lcf_hash->fh_name);
387         return rc;
388 }
389 EXPORT_SYMBOL(fld_client_init);
390
391 void fld_client_fini(struct lu_client_fld *fld)
392 {
393         struct lu_fld_target *target, *tmp;
394         ENTRY;
395
396         spin_lock(&fld->lcf_lock);
397         cfs_list_for_each_entry_safe(target, tmp,
398                                      &fld->lcf_targets, ft_chain) {
399                 fld->lcf_count--;
400                 cfs_list_del(&target->ft_chain);
401                 if (target->ft_exp != NULL)
402                         class_export_put(target->ft_exp);
403                 OBD_FREE_PTR(target);
404         }
405         spin_unlock(&fld->lcf_lock);
406
407         if (fld->lcf_cache != NULL) {
408                 if (!IS_ERR(fld->lcf_cache))
409                         fld_cache_fini(fld->lcf_cache);
410                 fld->lcf_cache = NULL;
411         }
412
413         EXIT;
414 }
415 EXPORT_SYMBOL(fld_client_fini);
416
417 int fld_client_rpc(struct obd_export *exp,
418                    struct lu_seq_range *range, __u32 fld_op)
419 {
420         struct ptlrpc_request *req;
421         struct lu_seq_range      *prange;
422         __u32                 *op;
423         int                    rc;
424         ENTRY;
425
426         LASSERT(exp != NULL);
427
428         req = ptlrpc_request_alloc_pack(class_exp2cliimp(exp), &RQF_FLD_QUERY,
429                                         LUSTRE_MDS_VERSION, FLD_QUERY);
430         if (req == NULL)
431                 RETURN(-ENOMEM);
432
433         op = req_capsule_client_get(&req->rq_pill, &RMF_FLD_OPC);
434         *op = fld_op;
435
436         prange = req_capsule_client_get(&req->rq_pill, &RMF_FLD_MDFLD);
437         *prange = *range;
438
439         ptlrpc_request_set_replen(req);
440         req->rq_request_portal = FLD_REQUEST_PORTAL;
441         ptlrpc_at_set_req_timeout(req);
442
443         if (fld_op != FLD_LOOKUP)
444                 mdc_get_rpc_lock(exp->exp_obd->u.cli.cl_rpc_lock, NULL);
445         fld_enter_request(&exp->exp_obd->u.cli);
446         rc = ptlrpc_queue_wait(req);
447         fld_exit_request(&exp->exp_obd->u.cli);
448         if (fld_op != FLD_LOOKUP)
449                 mdc_put_rpc_lock(exp->exp_obd->u.cli.cl_rpc_lock, NULL);
450         if (rc)
451                 GOTO(out_req, rc);
452
453         prange = req_capsule_server_get(&req->rq_pill, &RMF_FLD_MDFLD);
454         if (prange == NULL)
455                 GOTO(out_req, rc = -EFAULT);
456         *range = *prange;
457         EXIT;
458 out_req:
459         ptlrpc_req_finished(req);
460         return rc;
461 }
462
463 int fld_client_lookup(struct lu_client_fld *fld, seqno_t seq, mdsno_t *mds,
464                       __u32 flags, const struct lu_env *env)
465 {
466         struct lu_seq_range res;
467         struct lu_fld_target *target;
468         int rc;
469         ENTRY;
470
471         fld->lcf_flags |= LUSTRE_FLD_RUN;
472
473         rc = fld_cache_lookup(fld->lcf_cache, seq, &res);
474         if (rc == 0) {
475                 *mds = res.lsr_index;
476                 RETURN(0);
477         }
478
479         /* Can not find it in the cache */
480         target = fld_client_get_target(fld, seq);
481         LASSERT(target != NULL);
482
483         CDEBUG(D_INFO, "%s: Lookup fld entry (seq: "LPX64") on "
484                "target %s (idx "LPU64")\n", fld->lcf_name, seq,
485                fld_target_name(target), target->ft_idx);
486
487         res.lsr_start = seq;
488         res.lsr_flags = flags;
489 #ifdef __KERNEL__
490         if (target->ft_srv != NULL) {
491                 LASSERT(env != NULL);
492                 rc = fld_server_lookup(target->ft_srv,
493                                        env, seq, &res);
494         } else {
495 #endif
496                 rc = fld_client_rpc(target->ft_exp,
497                                     &res, FLD_LOOKUP);
498 #ifdef __KERNEL__
499         }
500 #endif
501
502         if (rc == 0) {
503                 *mds = res.lsr_index;
504
505                 fld_cache_insert(fld->lcf_cache, &res);
506         }
507         RETURN(rc);
508 }
509 EXPORT_SYMBOL(fld_client_lookup);
510
511 void fld_client_flush(struct lu_client_fld *fld)
512 {
513         fld_cache_flush(fld->lcf_cache);
514 }
515 EXPORT_SYMBOL(fld_client_flush);