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[fs/lustre-release.git] / lustre / obdecho / echo_client.c
1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
2  * vim:expandtab:shiftwidth=8:tabstop=8:
3  *
4  *  Copyright (c) 2001-2003 Cluster File Systems, Inc.
5  *
6  *   This file is part of Lustre, http://www.lustre.org.
7  *
8  *   Lustre is free software; you can redistribute it and/or
9  *   modify it under the terms of version 2 of the GNU General Public
10  *   License as published by the Free Software Foundation.
11  *
12  *   Lustre is distributed in the hope that it will be useful,
13  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
14  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  *   GNU General Public License for more details.
16  *
17  *   You should have received a copy of the GNU General Public License
18  *   along with Lustre; if not, write to the Free Software
19  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
20  */
21
22 #define DEBUG_SUBSYSTEM S_ECHO
23 #ifdef __KERNEL__
24 #include <linux/version.h>
25 #include <linux/module.h>
26 #include <linux/fs.h>
27 #include <linux/completion.h>
28 #if (LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0))
29 #include <linux/iobuf.h>
30 #endif
31 #include <asm/div64.h>
32 #else
33 #include <liblustre.h>
34 #endif
35
36 #include <linux/obd.h>
37 #include <linux/obd_support.h>
38 #include <linux/obd_class.h>
39 #include <linux/obd_echo.h>
40 #include <linux/lustre_debug.h>
41 #include <linux/lprocfs_status.h>
42
43 static obd_id last_object_id;
44
45 #if 0
46 static void
47 echo_printk_object (char *msg, struct ec_object *eco)
48 {
49         struct lov_stripe_md *lsm = eco->eco_lsm;
50         int                   i;
51
52         printk (KERN_INFO "Lustre: %s: object %p: "LPX64", refs %d%s: "LPX64
53                 "=%u!%u\n", msg, eco, eco->eco_id, eco->eco_refcount,
54                 eco->eco_deleted ? "(deleted) " : "",
55                 lsm->lsm_object_id, lsm->lsm_stripe_size,
56                 lsm->lsm_stripe_count);
57
58         for (i = 0; i < lsm->lsm_stripe_count; i++)
59                 printk (KERN_INFO "Lustre:   @%2u:"LPX64"\n",
60                         lsm->lsm_oinfo[i].loi_ost_idx,
61                         lsm->lsm_oinfo[i].loi_id);
62 }
63 #endif
64
65 static struct ec_object *
66 echo_find_object_locked (struct obd_device *obd, obd_id id)
67 {
68         struct echo_client_obd *ec = &obd->u.echo_client;
69         struct ec_object       *eco = NULL;
70         struct list_head       *el;
71
72         list_for_each (el, &ec->ec_objects) {
73                 eco = list_entry (el, struct ec_object, eco_obj_chain);
74
75                 if (eco->eco_id == id)
76                         return (eco);
77         }
78         return (NULL);
79 }
80
81 static int
82 echo_copyout_lsm (struct lov_stripe_md *lsm, void *ulsm, int ulsm_nob)
83 {
84         int nob;
85
86         nob = offsetof (struct lov_stripe_md, lsm_oinfo[lsm->lsm_stripe_count]);
87         if (nob > ulsm_nob)
88                 return (-EINVAL);
89
90         if (copy_to_user (ulsm, lsm, nob))
91                 return (-EFAULT);
92
93         return (0);
94 }
95
96 static int
97 echo_copyin_lsm (struct obd_device *obd, struct lov_stripe_md *lsm,
98                  void *ulsm, int ulsm_nob)
99 {
100         struct echo_client_obd *ec = &obd->u.echo_client;
101         int                     nob;
102
103         if (ulsm_nob < sizeof (*lsm))
104                 return (-EINVAL);
105
106         if (copy_from_user (lsm, ulsm, sizeof (*lsm)))
107                 return (-EFAULT);
108
109         nob = lsm->lsm_stripe_count * sizeof (lsm->lsm_oinfo[0]);
110
111         if (ulsm_nob < nob ||
112             lsm->lsm_stripe_count > ec->ec_nstripes ||
113             lsm->lsm_magic != LOV_MAGIC ||
114             (lsm->lsm_stripe_size & (PAGE_SIZE - 1)) != 0 ||
115             ((__u64)lsm->lsm_stripe_size * lsm->lsm_stripe_count > ~0UL))
116                 return (-EINVAL);
117
118         if (copy_from_user(lsm->lsm_oinfo,
119                            ((struct lov_stripe_md *)ulsm)->lsm_oinfo, nob))
120                 return (-EFAULT);
121
122         return (0);
123 }
124
125 static struct ec_object *
126 echo_allocate_object (struct obd_device *obd)
127 {
128         struct echo_client_obd *ec = &obd->u.echo_client;
129         struct ec_object       *eco;
130         int rc;
131
132         OBD_ALLOC(eco, sizeof (*eco));
133         if (eco == NULL)
134                 return NULL;
135
136         rc = obd_alloc_memmd(ec->ec_exp, &eco->eco_lsm);
137         if (rc < 0) {
138                 OBD_FREE(eco, sizeof (*eco));
139                 return NULL;
140         }
141
142         eco->eco_device = obd;
143         eco->eco_deleted = 0;
144         eco->eco_refcount = 0;
145         eco->eco_lsm->lsm_magic = LOV_MAGIC;
146         /* leave stripe count 0 by default */
147
148         return (eco);
149 }
150
151 static void
152 echo_free_object (struct ec_object *eco)
153 {
154         struct obd_device      *obd = eco->eco_device;
155         struct echo_client_obd *ec = &obd->u.echo_client;
156
157         LASSERT (eco->eco_refcount == 0);
158         obd_free_memmd(ec->ec_exp, &eco->eco_lsm);
159         OBD_FREE (eco, sizeof (*eco));
160 }
161
162 static int echo_create_object(struct obd_device *obd, int on_target,
163                               struct obdo *oa, void *ulsm, int ulsm_nob,
164                               struct obd_trans_info *oti)
165 {
166         struct echo_client_obd *ec = &obd->u.echo_client;
167         struct ec_object       *eco2;
168         struct ec_object       *eco;
169         struct lov_stripe_md   *lsm;
170         int                     rc;
171         int                     i, idx;
172
173         if ((oa->o_valid & OBD_MD_FLID) == 0 && /* no obj id */
174             (on_target ||                       /* set_stripe */
175              ec->ec_nstripes != 0)) {           /* LOV */
176                 CERROR ("No valid oid\n");
177                 return (-EINVAL);
178         }
179
180         if (ulsm != NULL) {
181                 eco = echo_allocate_object (obd);
182                 if (eco == NULL)
183                         return (-ENOMEM);
184
185                 lsm = eco->eco_lsm;
186
187                 rc = echo_copyin_lsm (obd, lsm, ulsm, ulsm_nob);
188                 if (rc != 0)
189                         goto failed;
190
191                 /* setup object ID here for !on_target and LOV hint */
192                 if ((oa->o_valid & OBD_MD_FLID) != 0)
193                         eco->eco_id = lsm->lsm_object_id = oa->o_id;
194
195                 if (lsm->lsm_stripe_count == 0)
196                         lsm->lsm_stripe_count = ec->ec_nstripes;
197
198                 if (lsm->lsm_stripe_size == 0)
199                         lsm->lsm_stripe_size = PAGE_SIZE;
200
201                 idx = ll_insecure_random_int();
202
203                 /* setup stripes: indices + default ids if required */
204                 for (i = 0; i < lsm->lsm_stripe_count; i++) {
205                         if (lsm->lsm_oinfo[i].loi_id == 0)
206                                 lsm->lsm_oinfo[i].loi_id = lsm->lsm_object_id;
207
208                         lsm->lsm_oinfo[i].loi_ost_idx =
209                                 (idx + i) % ec->ec_nstripes;
210                 }
211         } else {
212                 OBD_ALLOC(eco, sizeof(*eco));
213                 eco->eco_device = obd;
214                 lsm = NULL;
215         }
216
217         if (oa->o_id == 0)
218                 oa->o_id = ++last_object_id;
219
220         if (on_target) {
221                 /* XXX get some filter group constants */
222                 oa->o_gr = 2;
223                 oa->o_valid |= OBD_MD_FLGROUP;
224                 rc = obd_create(ec->ec_exp, oa, &lsm, oti);
225                 if (rc != 0)
226                         goto failed;
227
228                 /* See what object ID we were given */
229                 eco->eco_id = oa->o_id = lsm->lsm_object_id;
230                 oa->o_valid |= OBD_MD_FLID;
231
232                 LASSERT(eco->eco_lsm == NULL || eco->eco_lsm == lsm);
233                 eco->eco_lsm = lsm;
234         }
235
236         spin_lock (&ec->ec_lock);
237
238         eco2 = echo_find_object_locked (obd, oa->o_id);
239         if (eco2 != NULL) {                     /* conflict */
240                 spin_unlock (&ec->ec_lock);
241
242                 CERROR ("Can't create object id "LPX64": id already exists%s\n",
243                         oa->o_id, on_target ? " (undoing create)" : "");
244
245                 if (on_target)
246                         obd_destroy(ec->ec_exp, oa, lsm, oti);
247
248                 rc = -EEXIST;
249                 goto failed;
250         }
251
252         list_add (&eco->eco_obj_chain, &ec->ec_objects);
253         spin_unlock (&ec->ec_lock);
254         CDEBUG (D_INFO,
255                 "created %p: "LPX64"=%u#%u@%u refs %d del %d\n",
256                 eco, eco->eco_id,
257                 eco->eco_lsm->lsm_stripe_size,
258                 eco->eco_lsm->lsm_stripe_count,
259                 eco->eco_lsm->lsm_oinfo[0].loi_ost_idx,
260                 eco->eco_refcount, eco->eco_deleted);
261         return (0);
262
263  failed:
264         echo_free_object (eco);
265         return (rc);
266 }
267
268 static int
269 echo_get_object (struct ec_object **ecop, struct obd_device *obd,
270                  struct obdo *oa)
271 {
272         struct echo_client_obd *ec = &obd->u.echo_client;
273         struct ec_object       *eco;
274         struct ec_object       *eco2;
275         int                     rc;
276
277         if ((oa->o_valid & OBD_MD_FLID) == 0 ||
278             oa->o_id == 0)                      /* disallow use of object id 0 */
279         {
280                 CERROR ("No valid oid\n");
281                 return (-EINVAL);
282         }
283
284         spin_lock (&ec->ec_lock);
285         eco = echo_find_object_locked (obd, oa->o_id);
286         if (eco != NULL) {
287                 if (eco->eco_deleted)           /* being deleted */
288                         return (-EAGAIN);       /* (see comment in cleanup) */
289
290                 eco->eco_refcount++;
291                 spin_unlock (&ec->ec_lock);
292                 *ecop = eco;
293                 CDEBUG (D_INFO,
294                         "found %p: "LPX64"=%u#%u@%u refs %d del %d\n",
295                         eco, eco->eco_id,
296                         eco->eco_lsm->lsm_stripe_size,
297                         eco->eco_lsm->lsm_stripe_count,
298                         eco->eco_lsm->lsm_oinfo[0].loi_ost_idx,
299                         eco->eco_refcount, eco->eco_deleted);
300                 return (0);
301         }
302         spin_unlock (&ec->ec_lock);
303
304         if (ec->ec_nstripes != 0)               /* striping required */
305                 return (-ENOENT);
306
307         eco = echo_allocate_object (obd);
308         if (eco == NULL)
309                 return (-ENOMEM);
310
311         eco->eco_id = eco->eco_lsm->lsm_object_id = oa->o_id;
312
313         spin_lock (&ec->ec_lock);
314
315         eco2 = echo_find_object_locked (obd, oa->o_id);
316         if (eco2 == NULL) {                     /* didn't race */
317                 list_add (&eco->eco_obj_chain, &ec->ec_objects);
318                 spin_unlock (&ec->ec_lock);
319                 eco->eco_refcount = 1;
320                 *ecop = eco;
321                 CDEBUG (D_INFO,
322                         "created %p: "LPX64"=%u#%u@%d refs %d del %d\n",
323                         eco, eco->eco_id,
324                         eco->eco_lsm->lsm_stripe_size,
325                         eco->eco_lsm->lsm_stripe_count,
326                         eco->eco_lsm->lsm_oinfo[0].loi_ost_idx,
327                         eco->eco_refcount, eco->eco_deleted);
328                 return (0);
329         }
330
331         if (eco2->eco_deleted)
332                 rc = -EAGAIN;                   /* lose race */
333         else {
334                 eco2->eco_refcount++;           /* take existing */
335                 *ecop = eco2;
336                 rc = 0;
337                 LASSERT (eco2->eco_id == eco2->eco_lsm->lsm_object_id);
338                 CDEBUG (D_INFO,
339                         "found(2) %p: "LPX64"=%u#%u@%d refs %d del %d\n",
340                         eco2, eco2->eco_id,
341                         eco2->eco_lsm->lsm_stripe_size,
342                         eco2->eco_lsm->lsm_stripe_count,
343                         eco2->eco_lsm->lsm_oinfo[0].loi_ost_idx,
344                         eco2->eco_refcount, eco2->eco_deleted);
345         }
346
347         spin_unlock (&ec->ec_lock);
348
349         echo_free_object (eco);
350         return (rc);
351 }
352
353 static void
354 echo_put_object (struct ec_object *eco)
355 {
356         struct obd_device      *obd = eco->eco_device;
357         struct echo_client_obd *ec = &obd->u.echo_client;
358
359         /* Release caller's ref on the object.
360          * delete => mark for deletion when last ref goes
361          */
362
363         spin_lock (&ec->ec_lock);
364
365         eco->eco_refcount--;
366         LASSERT (eco->eco_refcount >= 0);
367
368         CDEBUG(D_INFO, "put %p: "LPX64"=%u#%u@%d refs %d del %d\n",
369                eco, eco->eco_id,
370                eco->eco_lsm->lsm_stripe_size,
371                eco->eco_lsm->lsm_stripe_count,
372                eco->eco_lsm->lsm_oinfo[0].loi_ost_idx,
373                eco->eco_refcount, eco->eco_deleted);
374
375         if (eco->eco_refcount != 0 || !eco->eco_deleted) {
376                 spin_unlock (&ec->ec_lock);
377                 return;
378         }
379
380         spin_unlock (&ec->ec_lock);
381
382         /* NB leave obj in the object list.  We must prevent anyone from
383          * attempting to enqueue on this object number until we can be
384          * sure there will be no more lock callbacks.
385          */
386         obd_cancel_unused(ec->ec_exp, eco->eco_lsm, 0, NULL);
387
388         /* now we can let it go */
389         spin_lock (&ec->ec_lock);
390         list_del (&eco->eco_obj_chain);
391         spin_unlock (&ec->ec_lock);
392
393         LASSERT (eco->eco_refcount == 0);
394
395         echo_free_object (eco);
396 }
397
398 static void
399 echo_get_stripe_off_id (struct lov_stripe_md *lsm, obd_off *offp, obd_id *idp)
400 {
401         unsigned long stripe_count;
402         unsigned long stripe_size;
403         unsigned long width;
404         unsigned long woffset;
405         int           stripe_index;
406         obd_off       offset;
407
408         if (lsm->lsm_stripe_count <= 1)
409                 return;
410
411         offset       = *offp;
412         stripe_size  = lsm->lsm_stripe_size;
413         stripe_count = lsm->lsm_stripe_count;
414
415         /* width = # bytes in all stripes */
416         width = stripe_size * stripe_count;
417
418         /* woffset = offset within a width; offset = whole number of widths */
419         woffset = do_div (offset, width);
420
421         stripe_index = woffset / stripe_size;
422
423         *idp = lsm->lsm_oinfo[stripe_index].loi_id;
424         *offp = offset * stripe_size + woffset % stripe_size;
425 }
426
427 static void 
428 echo_client_page_debug_setup(struct lov_stripe_md *lsm, 
429                              struct page *page, int rw, obd_id id, 
430                              obd_off offset, obd_off count)
431 {
432         char    *addr;
433         obd_off  stripe_off;
434         obd_id   stripe_id;
435         int      delta;
436
437         /* no partial pages on the client */
438         LASSERT(count == PAGE_SIZE);
439
440         addr = kmap(page);
441
442         for (delta = 0; delta < PAGE_SIZE; delta += OBD_ECHO_BLOCK_SIZE) {
443                 if (rw == OBD_BRW_WRITE) {
444                         stripe_off = offset + delta;
445                         stripe_id = id;
446                         echo_get_stripe_off_id(lsm, &stripe_off, &stripe_id);
447                 } else {
448                         stripe_off = 0xdeadbeef00c0ffeeULL;
449                         stripe_id = 0xdeadbeef00c0ffeeULL;
450                 }
451                 block_debug_setup(addr + delta, OBD_ECHO_BLOCK_SIZE, 
452                                   stripe_off, stripe_id);
453         }
454
455         kunmap(page);
456 }
457
458 static int
459 echo_client_page_debug_check(struct lov_stripe_md *lsm, 
460                              struct page *page, obd_id id, 
461                              obd_off offset, obd_off count)
462 {
463         obd_off stripe_off;
464         obd_id  stripe_id;
465         char   *addr;
466         int     delta;
467         int     rc;
468         int     rc2;
469
470         /* no partial pages on the client */
471         LASSERT(count == PAGE_SIZE);
472
473         addr = kmap(page);
474
475         for (rc = delta = 0; delta < PAGE_SIZE; delta += OBD_ECHO_BLOCK_SIZE) {
476                 stripe_off = offset + delta;
477                 stripe_id = id;
478                 echo_get_stripe_off_id (lsm, &stripe_off, &stripe_id);
479
480                 rc2 = block_debug_check("test_brw", 
481                                         addr + delta, OBD_ECHO_BLOCK_SIZE, 
482                                         stripe_off, stripe_id);
483                 if (rc2 != 0)
484                         rc = rc2;
485         }
486
487         kunmap(page);
488         return rc;
489 }
490
491 static int echo_client_kbrw(struct obd_device *obd, int rw, struct obdo *oa,
492                             struct lov_stripe_md *lsm, obd_off offset,
493                             obd_size count, struct obd_trans_info *oti)
494 {
495         struct echo_client_obd *ec = &obd->u.echo_client;
496         obd_count               npages;
497         struct brw_page        *pga;
498         struct brw_page        *pgp;
499         obd_off                 off;
500         int                     i;
501         int                     rc;
502         int                     verify = 0;
503         int                     gfp_mask;
504
505         /* oa_id == ECHO_PERSISTENT_OBJID => speed test (no verification).
506          * oa & 1                         => use HIGHMEM */
507
508         verify = (oa->o_id) != ECHO_PERSISTENT_OBJID;
509         gfp_mask = ((oa->o_id & 2) == 0) ? GFP_KERNEL : GFP_HIGHUSER;
510
511         LASSERT(rw == OBD_BRW_WRITE || rw == OBD_BRW_READ);
512
513         if (count <= 0 ||
514             (count & (PAGE_SIZE - 1)) != 0 ||
515             (lsm != NULL &&
516              lsm->lsm_object_id != oa->o_id))
517                 return (-EINVAL);
518
519         /* XXX think again with misaligned I/O */
520         npages = count >> PAGE_SHIFT;
521
522         OBD_ALLOC(pga, npages * sizeof(*pga));
523         if (pga == NULL)
524                 return (-ENOMEM);
525
526         for (i = 0, pgp = pga, off = offset;
527              i < npages;
528              i++, pgp++, off += PAGE_SIZE) {
529
530                 LASSERT (pgp->pg == NULL);      /* for cleanup */
531
532                 rc = -ENOMEM;
533                 pgp->pg = alloc_pages (gfp_mask, 0);
534                 if (pgp->pg == NULL)
535                         goto out;
536
537                 pgp->count = PAGE_SIZE;
538                 pgp->off = off;
539                 pgp->flag = 0;
540
541                 if (verify)
542                         echo_client_page_debug_setup(lsm, pgp->pg, rw, 
543                                                      oa->o_id, off, pgp->count);
544         }
545
546         rc = obd_brw(rw, ec->ec_exp, oa, lsm, npages, pga, oti);
547
548  out:
549         if (rc != 0 || rw != OBD_BRW_READ)
550                 verify = 0;
551
552         for (i = 0, pgp = pga; i < npages; i++, pgp++) {
553                 if (pgp->pg == NULL)
554                         continue;
555
556                 if (verify) {
557                         int vrc;
558                         vrc = echo_client_page_debug_check(lsm, pgp->pg, oa->o_id,
559                                                            pgp->off, pgp->count);
560                         if (vrc != 0 && rc == 0)
561                                 rc = vrc;
562                 }
563                 __free_pages(pgp->pg, 0);
564         }
565         OBD_FREE(pga, npages * sizeof(*pga));
566         return (rc);
567 }
568
569 #ifdef __KERNEL__
570 #if (LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0))
571 static int echo_client_ubrw(struct obd_device *obd, int rw,
572                             struct obdo *oa, struct lov_stripe_md *lsm,
573                             obd_off offset, obd_size count, char *buffer,
574                             struct obd_trans_info *oti)
575 {
576         struct echo_client_obd *ec = &obd->u.echo_client;
577         obd_count               npages;
578         struct brw_page        *pga;
579         struct brw_page        *pgp;
580         obd_off                 off;
581         struct kiobuf          *kiobuf;
582         int                     i;
583         int                     rc;
584
585         LASSERT (rw == OBD_BRW_WRITE ||
586                  rw == OBD_BRW_READ);
587
588         /* NB: for now, only whole pages, page aligned */
589
590         if (count <= 0 ||
591             ((long)buffer & (PAGE_SIZE - 1)) != 0 ||
592             (count & (PAGE_SIZE - 1)) != 0 ||
593             (lsm != NULL && lsm->lsm_object_id != oa->o_id))
594                 return (-EINVAL);
595
596         /* XXX think again with misaligned I/O */
597         npages = count >> PAGE_SHIFT;
598
599         OBD_ALLOC(pga, npages * sizeof(*pga));
600         if (pga == NULL)
601                 return (-ENOMEM);
602
603         rc = alloc_kiovec (1, &kiobuf);
604         if (rc != 0)
605                 goto out_1;
606
607         rc = map_user_kiobuf ((rw == OBD_BRW_READ) ? READ : WRITE,
608                               kiobuf, (unsigned long)buffer, count);
609         if (rc != 0)
610                 goto out_2;
611
612         LASSERT (kiobuf->offset == 0);
613         LASSERT (kiobuf->nr_pages == npages);
614
615         for (i = 0, off = offset, pgp = pga;
616              i < npages;
617              i++, off += PAGE_SIZE, pgp++) {
618                 pgp->off = off;
619                 pgp->pg = kiobuf->maplist[i];
620                 pgp->count = PAGE_SIZE;
621                 pgp->flag = 0;
622         }
623
624         rc = obd_brw(rw, ec->ec_exp, oa, lsm, npages, pga, oti);
625
626         //        if (rw == OBD_BRW_READ)
627         //                mark_dirty_kiobuf (kiobuf, count);
628
629         unmap_kiobuf (kiobuf);
630  out_2:
631         free_kiovec (1, &kiobuf);
632  out_1:
633         OBD_FREE(pga, npages * sizeof(*pga));
634         return (rc);
635 }
636 #else
637 static int echo_client_ubrw(struct obd_device *obd, int rw,
638                             struct obdo *oa, struct lov_stripe_md *lsm,
639                             obd_off offset, obd_size count, char *buffer,
640                             struct obd_trans_info *oti)
641 {
642 #warning "echo_client_ubrw() needs to be ported on 2.6 yet"
643         LBUG();
644         return 0;
645 }
646 #endif
647 #endif
648
649 struct echo_async_state;
650
651 #define EAP_MAGIC 79277927
652 struct echo_async_page {
653         int                     eap_magic;
654         struct page             *eap_page;
655         void                    *eap_cookie;
656         obd_off                 eap_off;
657         struct echo_async_state *eap_eas;
658         struct list_head        eap_item;
659 };
660
661 struct echo_async_state {
662         spinlock_t              eas_lock;
663         obd_off                 eas_next_offset;
664         obd_off                 eas_end_offset;
665         int                     eas_in_flight;
666         int                     eas_rc;
667         wait_queue_head_t       eas_waitq;
668         struct list_head        eas_avail;
669         struct obdo             eas_oa;
670         struct lov_stripe_md    *eas_lsm;
671 };
672
673 static int eas_should_wake(struct echo_async_state *eas)
674 {
675         unsigned long flags;
676         int rc = 0;
677         spin_lock_irqsave(&eas->eas_lock, flags);
678         if (eas->eas_rc == 0 && !list_empty(&eas->eas_avail))
679             rc = 1;
680         spin_unlock_irqrestore(&eas->eas_lock, flags);
681         return rc;
682 };
683
684 struct echo_async_page *eap_from_cookie(void *cookie)
685 {
686         struct echo_async_page *eap = cookie;
687         if (eap->eap_magic != EAP_MAGIC)
688                 return ERR_PTR(-EINVAL);
689         return eap;
690 };
691
692 static int ec_ap_make_ready(void *data, int cmd)
693 {
694         /* our pages are issued ready */
695         LBUG();
696         return 0;
697 }
698 static int ec_ap_refresh_count(void *data, int cmd)
699 {
700         /* our pages are issued with a stable count */
701         LBUG();
702         return PAGE_SIZE;
703 }
704 static void ec_ap_fill_obdo(void *data, int cmd, struct obdo *oa)
705 {
706         struct echo_async_page *eap;
707         eap = eap_from_cookie(data);
708         if (IS_ERR(eap))
709                 return;
710
711         memcpy(oa, &eap->eap_eas->eas_oa, sizeof(*oa));
712 }
713
714 static void ec_ap_completion(void *data, int cmd, struct obdo *oa, int rc)
715 {
716         struct echo_async_page *eap = eap_from_cookie(data);
717         struct echo_async_state *eas;
718         unsigned long flags;
719
720         if (IS_ERR(eap))
721                 return;
722         eas = eap->eap_eas;
723
724         if (cmd == OBD_BRW_READ &&
725             eas->eas_oa.o_id != ECHO_PERSISTENT_OBJID)
726                 echo_client_page_debug_check(eas->eas_lsm, eap->eap_page, 
727                                              eas->eas_oa.o_id, eap->eap_off,
728                                              PAGE_SIZE);
729
730         spin_lock_irqsave(&eas->eas_lock, flags);
731         if (rc && !eas->eas_rc)
732                 eas->eas_rc = rc;
733         eas->eas_in_flight--;
734         list_add(&eap->eap_item, &eas->eas_avail);
735         wake_up(&eas->eas_waitq);
736         spin_unlock_irqrestore(&eas->eas_lock, flags);
737 }
738
739 static struct obd_async_page_ops ec_async_page_ops = {
740         .ap_make_ready =        ec_ap_make_ready,
741         .ap_refresh_count =     ec_ap_refresh_count,
742         .ap_fill_obdo =         ec_ap_fill_obdo,
743         .ap_completion =        ec_ap_completion,
744 };
745
746 static int echo_client_async_page(struct obd_export *exp, int rw,
747                                    struct obdo *oa, struct lov_stripe_md *lsm,
748                                    obd_off offset, obd_size count,
749                                    obd_size batching)
750 {
751         obd_count npages, i;
752         struct echo_async_page *eap;
753         struct echo_async_state eas;
754         struct list_head *pos, *n;
755         int rc = 0;
756         unsigned long flags;
757         LIST_HEAD(pages);
758 #if 0
759         int                     verify;
760         int                     gfp_mask;
761         /* oa_id  == 0    => speed test (no verification) else...
762          * oa & 1         => use HIGHMEM
763          */
764         verify = (oa->o_id != 0);
765         gfp_mask = ((oa->o_id & 1) == 0) ? GFP_KERNEL : GFP_HIGHUSER;
766 #endif
767
768         LASSERT(rw == OBD_BRW_WRITE || rw == OBD_BRW_READ);
769
770         if (count <= 0 ||
771             (count & (PAGE_SIZE - 1)) != 0 ||
772             (lsm != NULL &&
773              lsm->lsm_object_id != oa->o_id))
774                 return (-EINVAL);
775
776         /* XXX think again with misaligned I/O */
777         npages = batching >> PAGE_SHIFT;
778
779         memcpy(&eas.eas_oa, oa, sizeof(*oa));
780         eas.eas_next_offset = offset;
781         eas.eas_end_offset = offset + count;
782         spin_lock_init(&eas.eas_lock);
783         init_waitqueue_head(&eas.eas_waitq);
784         eas.eas_in_flight = 0;
785         eas.eas_rc = 0;
786         eas.eas_lsm = lsm;
787         INIT_LIST_HEAD(&eas.eas_avail);
788
789         /* prepare the group of pages that we're going to be keeping
790          * in flight */
791         for (i = 0; i < npages; i++) {
792                 struct page *page = alloc_page(GFP_KERNEL);
793                 if (page == NULL)
794                         GOTO(out, rc = -ENOMEM);
795
796                 page->private = 0;
797                 list_add_tail(&PAGE_LIST(page), &pages);
798
799                 OBD_ALLOC(eap, sizeof(*eap));
800                 if (eap == NULL)
801                         GOTO(out, rc = -ENOMEM);
802
803                 eap->eap_magic = EAP_MAGIC;
804                 eap->eap_page = page;
805                 eap->eap_eas = &eas;
806                 page->private = (unsigned long)eap;
807                 list_add_tail(&eap->eap_item, &eas.eas_avail);
808         }
809
810         /* first we spin queueing io and being woken by its completion */
811         spin_lock_irqsave(&eas.eas_lock, flags);
812         for(;;) {
813                 int rc;
814
815                 /* sleep until we have a page to send */
816                 spin_unlock_irqrestore(&eas.eas_lock, flags);
817                 rc = wait_event_interruptible(eas.eas_waitq, 
818                                               eas_should_wake(&eas));
819                 spin_lock_irqsave(&eas.eas_lock, flags);
820                 if (rc && !eas.eas_rc)
821                         eas.eas_rc = rc;
822                 if (eas.eas_rc)
823                         break;
824                 if (list_empty(&eas.eas_avail))
825                         continue;
826                 eap = list_entry(eas.eas_avail.next, struct echo_async_page,
827                                  eap_item);
828                 list_del(&eap->eap_item);
829                 spin_unlock_irqrestore(&eas.eas_lock, flags);
830
831                 /* unbind the eap from its old page offset */
832                 if (eap->eap_cookie != NULL) {
833                         obd_teardown_async_page(exp, lsm, NULL, 
834                                                 eap->eap_cookie);
835                         eap->eap_cookie = NULL;
836                 }
837
838                 eas.eas_next_offset += PAGE_SIZE;
839                 eap->eap_off = eas.eas_next_offset;
840
841                 rc = obd_prep_async_page(exp, lsm, NULL, eap->eap_page,
842                                          eap->eap_off, &ec_async_page_ops,
843                                          eap, &eap->eap_cookie);
844                 if (rc) {
845                         spin_lock_irqsave(&eas.eas_lock, flags);
846                         eas.eas_rc = rc;
847                         break;
848                 }
849
850                 if (oa->o_id != ECHO_PERSISTENT_OBJID)
851                         echo_client_page_debug_setup(lsm, eap->eap_page, rw, 
852                                                      oa->o_id, 
853                                                      eap->eap_off, PAGE_SIZE);
854
855                 /* always asserts urgent, which isn't quite right */
856                 rc = obd_queue_async_io(exp, lsm, NULL, eap->eap_cookie,
857                                         rw, 0, PAGE_SIZE, 0,
858                                         ASYNC_READY | ASYNC_URGENT |
859                                         ASYNC_COUNT_STABLE);
860                 spin_lock_irqsave(&eas.eas_lock, flags);
861                 if (rc && !eas.eas_rc) {
862                         eas.eas_rc = rc;
863                         break;
864                 }
865                 eas.eas_in_flight++;
866                 if (eas.eas_next_offset == eas.eas_end_offset)
867                         break;
868         } 
869
870         /* still hold the eas_lock here.. */
871
872         /* now we just spin waiting for all the rpcs to complete */
873         while(eas.eas_in_flight) {
874                 spin_unlock_irqrestore(&eas.eas_lock, flags);
875                 wait_event_interruptible(eas.eas_waitq, 
876                                          eas.eas_in_flight == 0);
877                 spin_lock_irqsave(&eas.eas_lock, flags);
878         }
879         spin_unlock_irqrestore(&eas.eas_lock, flags);
880
881 out:
882         list_for_each_safe(pos, n, &pages) {
883                 struct page *page = list_entry(pos, struct page, 
884                                                PAGE_LIST_ENTRY);
885
886                 list_del(&PAGE_LIST(page));
887                 if (page->private != 0) {
888                         eap = (struct echo_async_page *)page->private;
889                         if (eap->eap_cookie != NULL)
890                                 obd_teardown_async_page(exp, lsm, NULL, 
891                                                         eap->eap_cookie);
892                         OBD_FREE(eap, sizeof(*eap));
893                 }
894                 __free_page(page);
895         }
896
897         RETURN(rc);
898 }
899
900 static int echo_client_prep_commit(struct obd_export *exp, int rw,
901                                    struct obdo *oa, struct lov_stripe_md *lsm,
902                                    obd_off offset, obd_size count,  
903                                    obd_size batch, struct obd_trans_info *oti)
904 {
905         struct obd_ioobj ioo;
906         struct niobuf_local *lnb;
907         struct niobuf_remote *rnb;
908         obd_off off;
909         obd_size npages, tot_pages;
910         int i, ret = 0;
911         ENTRY;
912
913         if (count <= 0 || (count & (PAGE_SIZE - 1)) != 0 ||
914             (lsm != NULL && lsm->lsm_object_id != oa->o_id))
915                 RETURN(-EINVAL);
916
917         npages = batch >> PAGE_SHIFT;
918         tot_pages = count >> PAGE_SHIFT;
919
920         OBD_ALLOC(lnb, npages * sizeof(struct niobuf_local));
921         OBD_ALLOC(rnb, npages * sizeof(struct niobuf_remote));
922
923         if (lnb == NULL || rnb == NULL)
924                 GOTO(out, ret = -ENOMEM);
925
926         obdo_to_ioobj(oa, &ioo);
927
928         off = offset;
929
930         for(; tot_pages; tot_pages -= npages) {
931                 if (tot_pages < npages)
932                         npages = tot_pages;
933
934                 for (i = 0; i < npages; i++, off += PAGE_SIZE) {
935                         rnb[i].offset = off;
936                         rnb[i].len = PAGE_SIZE;
937                 }
938
939                 /* XXX this can't be the best.. */
940                 memset(oti, 0, sizeof(*oti));
941                 ioo.ioo_bufcnt = npages;
942
943                 ret = obd_preprw(rw, exp, oa, 1, &ioo, npages, rnb, lnb, oti);
944                 if (ret != 0)
945                         GOTO(out, ret);
946
947                 for (i = 0; i < npages; i++) {
948                         struct page *page = lnb[i].page;
949
950                         /* read past eof? */
951                         if (page == NULL && lnb[i].rc == 0)
952                                 continue;
953
954                         if (oa->o_id == ECHO_PERSISTENT_OBJID)
955                                 continue;
956
957                         if (rw == OBD_BRW_WRITE)
958                                 echo_client_page_debug_setup(lsm, page, rw,
959                                                              oa->o_id,
960                                                              rnb[i].offset,
961                                                              rnb[i].len);
962                         else
963                                 echo_client_page_debug_check(lsm, page,
964                                                              oa->o_id,
965                                                              rnb[i].offset,
966                                                              rnb[i].len);
967                 }
968
969                 ret = obd_commitrw(rw, exp, oa, 1, &ioo, npages, lnb, oti, ret);
970                 if (ret != 0)
971                         GOTO(out, ret);
972         }
973
974 out:
975         if (lnb)
976                 OBD_FREE(lnb, npages * sizeof(struct niobuf_local));
977         if (rnb)
978                 OBD_FREE(rnb, npages * sizeof(struct niobuf_remote));
979         RETURN(ret);
980 }
981
982 int echo_client_brw_ioctl(int rw, struct obd_export *exp,
983                           struct obd_ioctl_data *data)
984 {
985         struct obd_device *obd = class_exp2obd(exp);
986         struct echo_client_obd *ec = &obd->u.echo_client;
987         struct obd_trans_info dummy_oti;
988         struct ec_object *eco;
989         int rc;
990         ENTRY;
991
992         rc = echo_get_object(&eco, obd, &data->ioc_obdo1);
993         if (rc)
994                 RETURN(rc);
995
996         memset(&dummy_oti, 0, sizeof(dummy_oti));
997
998         data->ioc_obdo1.o_valid &= ~OBD_MD_FLHANDLE;
999         data->ioc_obdo1.o_valid |= OBD_MD_FLGROUP;
1000         data->ioc_obdo1.o_gr = 2;
1001
1002         switch((long)data->ioc_pbuf1) {
1003         case 1:
1004                 if (data->ioc_pbuf2 == NULL) { // NULL user data pointer
1005                         rc = echo_client_kbrw(obd, rw, &data->ioc_obdo1,
1006                                               eco->eco_lsm, data->ioc_offset,
1007                                               data->ioc_count, &dummy_oti);
1008                 } else {
1009 #ifdef __KERNEL__
1010                         rc = echo_client_ubrw(obd, rw, &data->ioc_obdo1,
1011                                               eco->eco_lsm, data->ioc_offset,
1012                                               data->ioc_count, data->ioc_pbuf2,
1013                                               &dummy_oti);
1014 #endif
1015                 }
1016                 break;
1017         case 2:
1018                 rc = echo_client_async_page(ec->ec_exp, rw, &data->ioc_obdo1,
1019                                            eco->eco_lsm, data->ioc_offset,
1020                                            data->ioc_count, data->ioc_plen1);
1021                 break;
1022         case 3:
1023                 rc = echo_client_prep_commit(ec->ec_exp, rw, &data->ioc_obdo1,
1024                                             eco->eco_lsm, data->ioc_offset,
1025                                             data->ioc_count, data->ioc_plen1,
1026                                             &dummy_oti);
1027                 break;
1028         default:
1029                 rc = -EINVAL;
1030         }
1031         echo_put_object(eco);
1032         RETURN(rc);
1033 }
1034
1035 static int
1036 echo_ldlm_callback (struct ldlm_lock *lock, struct ldlm_lock_desc *new,
1037                     void *data, int flag)
1038 {
1039         struct ec_object       *eco = (struct ec_object *)data;
1040         struct echo_client_obd *ec = &(eco->eco_device->u.echo_client);
1041         struct lustre_handle    lockh;
1042         struct list_head       *el;
1043         int                     found = 0;
1044         int                     rc;
1045
1046         ldlm_lock2handle (lock, &lockh);
1047
1048         /* #ifdef this out if we're not feeling paranoid */
1049         spin_lock (&ec->ec_lock);
1050         list_for_each (el, &ec->ec_objects) {
1051                 found = (eco == list_entry(el, struct ec_object,
1052                                            eco_obj_chain));
1053                 if (found)
1054                         break;
1055         }
1056         spin_unlock (&ec->ec_lock);
1057         LASSERT (found);
1058
1059         switch (flag) {
1060         case LDLM_CB_BLOCKING:
1061                 CDEBUG(D_INFO, "blocking callback on "LPX64", handle "LPX64"\n",
1062                        eco->eco_id, lockh.cookie);
1063                 rc = ldlm_cli_cancel (&lockh);
1064                 if (rc != ELDLM_OK)
1065                         CERROR ("ldlm_cli_cancel failed: %d\n", rc);
1066                 break;
1067
1068         case LDLM_CB_CANCELING:
1069                 CDEBUG(D_INFO, "cancel callback on "LPX64", handle "LPX64"\n",
1070                        eco->eco_id, lockh.cookie);
1071                 break;
1072
1073         default:
1074                 LBUG ();
1075         }
1076
1077         return (0);
1078 }
1079
1080 static int
1081 echo_client_enqueue(struct obd_export *exp, struct obdo *oa,
1082                     int mode, obd_off offset, obd_size nob)
1083 {
1084         struct obd_device      *obd = exp->exp_obd;
1085         struct echo_client_obd *ec = &obd->u.echo_client;
1086         struct lustre_handle   *ulh = obdo_handle (oa);
1087         struct ec_object       *eco;
1088         struct ec_lock         *ecl;
1089         int                     flags;
1090         int                     rc;
1091
1092         if (!(mode == LCK_PR || mode == LCK_PW))
1093                 return -EINVAL;
1094
1095         if ((offset & (PAGE_SIZE - 1)) != 0 ||
1096             (nob & (PAGE_SIZE - 1)) != 0)
1097                 return -EINVAL;
1098
1099         rc = echo_get_object (&eco, obd, oa);
1100         if (rc != 0)
1101                 return rc;
1102
1103         rc = -ENOMEM;
1104         OBD_ALLOC (ecl, sizeof (*ecl));
1105         if (ecl == NULL)
1106                 goto failed_0;
1107
1108         ecl->ecl_mode = mode;
1109         ecl->ecl_object = eco;
1110         ecl->ecl_policy.l_extent.start = offset;
1111         ecl->ecl_policy.l_extent.end =
1112                 (nob == 0) ? ((obd_off) -1) : (offset + nob - 1);
1113
1114         flags = 0;
1115         rc = obd_enqueue(ec->ec_exp, eco->eco_lsm, LDLM_EXTENT,
1116                          &ecl->ecl_policy, mode, &flags, echo_ldlm_callback,
1117                          ldlm_completion_ast, NULL, eco, sizeof(struct ost_lvb),
1118                          lustre_swab_ost_lvb, &ecl->ecl_lock_handle);
1119         if (rc != 0)
1120                 goto failed_1;
1121
1122         CDEBUG(D_INFO, "enqueue handle "LPX64"\n", ecl->ecl_lock_handle.cookie);
1123
1124         /* NB ecl takes object ref from echo_get_object() above */
1125         spin_lock(&ec->ec_lock);
1126
1127         list_add(&ecl->ecl_exp_chain, &exp->exp_ec_data.eced_locks);
1128         ulh->cookie = ecl->ecl_cookie = ec->ec_unique++;
1129
1130         spin_unlock(&ec->ec_lock);
1131
1132         oa->o_valid |= OBD_MD_FLHANDLE;
1133         return 0;
1134
1135  failed_1:
1136         OBD_FREE (ecl, sizeof (*ecl));
1137  failed_0:
1138         echo_put_object (eco);
1139         return (rc);
1140 }
1141
1142 static int
1143 echo_client_cancel(struct obd_export *exp, struct obdo *oa)
1144 {
1145         struct obd_device      *obd = exp->exp_obd;
1146         struct echo_client_obd *ec = &obd->u.echo_client;
1147         struct lustre_handle   *ulh = obdo_handle (oa);
1148         struct ec_lock         *ecl = NULL;
1149         int                     found = 0;
1150         struct list_head       *el;
1151         int                     rc;
1152
1153         if ((oa->o_valid & OBD_MD_FLHANDLE) == 0)
1154                 return -EINVAL;
1155
1156         spin_lock (&ec->ec_lock);
1157
1158         list_for_each (el, &exp->exp_ec_data.eced_locks) {
1159                 ecl = list_entry (el, struct ec_lock, ecl_exp_chain);
1160                 found = (ecl->ecl_cookie == ulh->cookie);
1161                 if (found) {
1162                         list_del (&ecl->ecl_exp_chain);
1163                         break;
1164                 }
1165         }
1166
1167         spin_unlock (&ec->ec_lock);
1168
1169         if (!found)
1170                 return (-ENOENT);
1171
1172         rc = obd_cancel(ec->ec_exp, ecl->ecl_object->eco_lsm, ecl->ecl_mode,
1173                         &ecl->ecl_lock_handle);
1174
1175         echo_put_object (ecl->ecl_object);
1176         OBD_FREE (ecl, sizeof (*ecl));
1177
1178         return rc;
1179 }
1180
1181 static int
1182 echo_client_iocontrol(unsigned int cmd, struct obd_export *exp,
1183                       int len, void *karg, void *uarg)
1184 {
1185         struct obd_device      *obd;
1186         struct echo_client_obd *ec;
1187         struct ec_object       *eco;
1188         struct obd_ioctl_data  *data = karg;
1189         struct obd_trans_info   dummy_oti;
1190         struct oti_req_ack_lock *ack_lock;
1191         struct obdo            *oa;
1192         int                     rw = OBD_BRW_READ;
1193         int                     rc = 0;
1194         int                     i;
1195         ENTRY;
1196
1197         memset(&dummy_oti, 0, sizeof(dummy_oti));
1198
1199         obd = exp->exp_obd;
1200         ec = &obd->u.echo_client;
1201
1202         switch (cmd) {
1203         case OBD_IOC_CREATE:                    /* may create echo object */
1204                 if (!capable (CAP_SYS_ADMIN))
1205                         GOTO (out, rc = -EPERM);
1206
1207                 rc = echo_create_object (obd, 1, &data->ioc_obdo1,
1208                                          data->ioc_pbuf1, data->ioc_plen1,
1209                                          &dummy_oti);
1210                 GOTO(out, rc);
1211
1212         case OBD_IOC_DESTROY:
1213                 if (!capable (CAP_SYS_ADMIN))
1214                         GOTO (out, rc = -EPERM);
1215
1216                 rc = echo_get_object (&eco, obd, &data->ioc_obdo1);
1217                 if (rc == 0) {
1218                         oa = &data->ioc_obdo1;
1219                         oa->o_gr = 2;
1220                         oa->o_valid |= OBD_MD_FLGROUP;
1221                         rc = obd_destroy(ec->ec_exp, oa, eco->eco_lsm, 
1222                                          &dummy_oti);
1223                         if (rc == 0)
1224                                 eco->eco_deleted = 1;
1225                         echo_put_object(eco);
1226                 }
1227                 GOTO(out, rc);
1228
1229         case OBD_IOC_GETATTR:
1230                 rc = echo_get_object (&eco, obd, &data->ioc_obdo1);
1231                 if (rc == 0) {
1232                         rc = obd_getattr(ec->ec_exp, &data->ioc_obdo1,
1233                                          eco->eco_lsm);
1234                         echo_put_object(eco);
1235                 }
1236                 GOTO(out, rc);
1237
1238         case OBD_IOC_SETATTR:
1239                 if (!capable (CAP_SYS_ADMIN))
1240                         GOTO (out, rc = -EPERM);
1241
1242                 rc = echo_get_object (&eco, obd, &data->ioc_obdo1);
1243                 if (rc == 0) {
1244                         rc = obd_setattr(ec->ec_exp, &data->ioc_obdo1,
1245                                          eco->eco_lsm, NULL);
1246                         echo_put_object(eco);
1247                 }
1248                 GOTO(out, rc);
1249
1250         case OBD_IOC_BRW_WRITE:
1251                 if (!capable (CAP_SYS_ADMIN))
1252                         GOTO (out, rc = -EPERM);
1253
1254                 rw = OBD_BRW_WRITE;
1255                 /* fall through */
1256         case OBD_IOC_BRW_READ:
1257                 rc = echo_client_brw_ioctl(rw, exp, data);
1258                 GOTO(out, rc);
1259
1260         case ECHO_IOC_GET_STRIPE:
1261                 rc = echo_get_object(&eco, obd, &data->ioc_obdo1);
1262                 if (rc == 0) {
1263                         rc = echo_copyout_lsm(eco->eco_lsm, data->ioc_pbuf1,
1264                                               data->ioc_plen1);
1265                         echo_put_object(eco);
1266                 }
1267                 GOTO(out, rc);
1268
1269         case ECHO_IOC_SET_STRIPE:
1270                 if (!capable (CAP_SYS_ADMIN))
1271                         GOTO (out, rc = -EPERM);
1272
1273                 if (data->ioc_pbuf1 == NULL) {  /* unset */
1274                         rc = echo_get_object(&eco, obd, &data->ioc_obdo1);
1275                         if (rc == 0) {
1276                                 eco->eco_deleted = 1;
1277                                 echo_put_object(eco);
1278                         }
1279                 } else {
1280                         rc = echo_create_object(obd, 0, &data->ioc_obdo1,
1281                                                 data->ioc_pbuf1,
1282                                                 data->ioc_plen1, &dummy_oti);
1283                 }
1284                 GOTO (out, rc);
1285
1286         case ECHO_IOC_ENQUEUE:
1287                 if (!capable (CAP_SYS_ADMIN))
1288                         GOTO (out, rc = -EPERM);
1289
1290                 rc = echo_client_enqueue(exp, &data->ioc_obdo1,
1291                                          data->ioc_conn1, /* lock mode */
1292                                    data->ioc_offset, data->ioc_count);/*extent*/
1293                 GOTO (out, rc);
1294
1295         case ECHO_IOC_CANCEL:
1296                 rc = echo_client_cancel(exp, &data->ioc_obdo1);
1297                 GOTO (out, rc);
1298
1299         default:
1300                 CERROR ("echo_ioctl(): unrecognised ioctl %#x\n", cmd);
1301                 GOTO (out, rc = -ENOTTY);
1302         }
1303
1304         EXIT;
1305  out:
1306
1307         /* XXX this should be in a helper also called by target_send_reply */
1308         for (ack_lock = dummy_oti.oti_ack_locks, i = 0; i < 4; 
1309              i++, ack_lock++) {
1310                 if (!ack_lock->mode)
1311                         break;
1312                 ldlm_lock_decref(&ack_lock->lock, ack_lock->mode);
1313         }
1314
1315         return rc;
1316 }
1317
1318 static int
1319 echo_client_setup(struct obd_device *obddev, obd_count len, void *buf)
1320 {
1321         struct lustre_cfg* lcfg = buf;
1322         struct echo_client_obd *ec = &obddev->u.echo_client;
1323         struct obd_device *tgt;
1324         struct lustre_handle conn = {0, };
1325         struct obd_uuid echo_uuid = { "ECHO_UUID" };
1326         int rc;
1327         ENTRY;
1328
1329         if (lcfg->lcfg_inllen1 < 1) {
1330                 CERROR("requires a TARGET OBD name\n");
1331                 RETURN(-EINVAL);
1332         }
1333
1334         tgt = class_name2obd(lcfg->lcfg_inlbuf1);
1335         if (!tgt || !tgt->obd_attached || !tgt->obd_set_up) {
1336                 CERROR("device not attached or not set up (%s)\n",
1337                        lcfg->lcfg_inlbuf1);
1338                 RETURN(-EINVAL);
1339         }
1340
1341         spin_lock_init (&ec->ec_lock);
1342         INIT_LIST_HEAD (&ec->ec_objects);
1343         ec->ec_unique = 0;
1344
1345         rc = obd_connect(&conn, tgt, &echo_uuid);
1346         if (rc) {
1347                 CERROR("fail to connect to device %s\n", lcfg->lcfg_inlbuf1);
1348                 return (rc);
1349         }
1350         ec->ec_exp = class_conn2export(&conn);
1351
1352         RETURN(rc);
1353 }
1354
1355 static int echo_client_cleanup(struct obd_device *obddev, int flags)
1356 {
1357         struct list_head       *el;
1358         struct ec_object       *eco;
1359         struct echo_client_obd *ec = &obddev->u.echo_client;
1360         int rc;
1361         ENTRY;
1362
1363         if (!list_empty(&obddev->obd_exports)) {
1364                 CERROR("still has clients!\n");
1365                 RETURN(-EBUSY);
1366         }
1367
1368         /* XXX assuming sole access */
1369         while (!list_empty(&ec->ec_objects)) {
1370                 el = ec->ec_objects.next;
1371                 eco = list_entry(el, struct ec_object, eco_obj_chain);
1372
1373                 LASSERT(eco->eco_refcount == 0);
1374                 eco->eco_refcount = 1;
1375                 eco->eco_deleted = 1;
1376                 echo_put_object(eco);
1377         }
1378
1379         rc = obd_disconnect(ec->ec_exp, 0);
1380         if (rc != 0)
1381                 CERROR("fail to disconnect device: %d\n", rc);
1382
1383         RETURN(rc);
1384 }
1385
1386 static int echo_client_connect(struct lustre_handle *conn,
1387                                struct obd_device *src, struct obd_uuid *cluuid)
1388 {
1389         struct obd_export *exp;
1390         int                rc;
1391
1392         rc = class_connect(conn, src, cluuid);
1393         if (rc == 0) {
1394                 exp = class_conn2export(conn);
1395                 INIT_LIST_HEAD(&exp->exp_ec_data.eced_locks);
1396                 class_export_put(exp);
1397         }
1398
1399         RETURN (rc);
1400 }
1401
1402 static int echo_client_disconnect(struct obd_export *exp, int flags)
1403 {
1404         struct obd_device      *obd;
1405         struct echo_client_obd *ec;
1406         struct ec_lock         *ecl;
1407         int                     rc;
1408         ENTRY;
1409
1410         if (exp == NULL)
1411                 GOTO(out, rc = -EINVAL);
1412
1413         obd = exp->exp_obd;
1414         ec = &obd->u.echo_client;
1415
1416         /* no more contention on export's lock list */
1417         while (!list_empty (&exp->exp_ec_data.eced_locks)) {
1418                 ecl = list_entry (exp->exp_ec_data.eced_locks.next,
1419                                   struct ec_lock, ecl_exp_chain);
1420                 list_del (&ecl->ecl_exp_chain);
1421
1422                 rc = obd_cancel(ec->ec_exp, ecl->ecl_object->eco_lsm,
1423                                  ecl->ecl_mode, &ecl->ecl_lock_handle);
1424
1425                 CDEBUG (D_INFO, "Cancel lock on object "LPX64" on disconnect "
1426                         "(%d)\n", ecl->ecl_object->eco_id, rc);
1427
1428                 echo_put_object (ecl->ecl_object);
1429                 OBD_FREE (ecl, sizeof (*ecl));
1430         }
1431
1432         rc = class_disconnect(exp, 0);
1433         GOTO(out, rc);
1434  out:
1435         return rc;
1436 }
1437
1438 static struct obd_ops echo_obd_ops = {
1439         o_owner:       THIS_MODULE,
1440         o_setup:       echo_client_setup,
1441         o_cleanup:     echo_client_cleanup,
1442         o_iocontrol:   echo_client_iocontrol,
1443         o_connect:     echo_client_connect,
1444         o_disconnect:  echo_client_disconnect
1445 };
1446
1447 int echo_client_init(void)
1448 {
1449         struct lprocfs_static_vars lvars;
1450
1451         lprocfs_init_vars(echo, &lvars);
1452         return class_register_type(&echo_obd_ops, lvars.module_vars,
1453                                    OBD_ECHO_CLIENT_DEVICENAME);
1454 }
1455
1456 void echo_client_exit(void)
1457 {
1458         class_unregister_type(OBD_ECHO_CLIENT_DEVICENAME);
1459 }