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[fs/lustre-release.git] / lustre / obdfilter / filter_io.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
24  * have any questions.
25  *
26  * GPL HEADER END
27  */
28 /*
29  * Copyright  2008 Sun Microsystems, Inc. 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  * lustre/obdfilter/filter_io.c
37  *
38  * Author: Peter Braam <braam@clusterfs.com>
39  * Author: Andreas Dilger <adilger@clusterfs.com>
40  * Author: Phil Schwan <phil@clusterfs.com>
41  */
42
43 #define DEBUG_SUBSYSTEM S_FILTER
44
45 #ifndef AUTOCONF_INCLUDED
46 #include <linux/config.h>
47 #endif
48 #include <linux/module.h>
49 #include <linux/pagemap.h> // XXX kill me soon
50 #include <linux/version.h>
51
52 #include <obd_class.h>
53 #include <obd_ost.h>
54 #include <lustre_fsfilt.h>
55 #include "filter_internal.h"
56
57 int *obdfilter_created_scratchpad;
58
59 static int filter_alloc_dio_page(struct obd_device *obd, struct inode *inode,
60                                  struct niobuf_local *lnb)
61 {
62         struct page *page;
63
64         LASSERT(lnb->page != NULL);
65
66         page = lnb->page;
67 #if 0
68         POISON_PAGE(page, 0xf1);
69         if (lnb->len != CFS_PAGE_SIZE) {
70                 memset(kmap(page) + lnb->len, 0, CFS_PAGE_SIZE - lnb->len);
71                 kunmap(page);
72         }
73 #endif
74         page->index = lnb->offset >> CFS_PAGE_SHIFT;
75
76         RETURN(0);
77 }
78
79 static void filter_free_dio_pages(int objcount, struct obd_ioobj *obj,
80                            int niocount, struct niobuf_local *res)
81 {
82         int i, j;
83
84         for (i = 0; i < objcount; i++, obj++) {
85                 for (j = 0 ; j < obj->ioo_bufcnt ; j++, res++)
86                                 res->page = NULL;
87         }
88 }
89
90 /* Grab the dirty and seen grant announcements from the incoming obdo.
91  * We will later calculate the clients new grant and return it.
92  * Caller must hold osfs lock */
93 static void filter_grant_incoming(struct obd_export *exp, struct obdo *oa)
94 {
95         struct filter_export_data *fed;
96         struct obd_device *obd = exp->exp_obd;
97         ENTRY;
98
99         LASSERT_SPIN_LOCKED(&obd->obd_osfs_lock);
100
101         if ((oa->o_valid & (OBD_MD_FLBLOCKS|OBD_MD_FLGRANT)) !=
102                                         (OBD_MD_FLBLOCKS|OBD_MD_FLGRANT)) {
103                 oa->o_valid &= ~OBD_MD_FLGRANT;
104                 EXIT;
105                 return;
106         }
107
108         fed = &exp->exp_filter_data;
109
110         /* Add some margin, since there is a small race if other RPCs arrive
111          * out-or-order and have already consumed some grant.  We want to
112          * leave this here in case there is a large error in accounting. */
113         CDEBUG(D_CACHE,
114                "%s: cli %s/%p reports grant: "LPU64" dropped: %u, local: %lu\n",
115                obd->obd_name, exp->exp_client_uuid.uuid, exp, oa->o_grant,
116                oa->o_dropped, fed->fed_grant);
117
118         /* Update our accounting now so that statfs takes it into account.
119          * Note that fed_dirty is only approximate and can become incorrect
120          * if RPCs arrive out-of-order.  No important calculations depend
121          * on fed_dirty however, but we must check sanity to not assert. */
122         if ((long long)oa->o_dirty < 0)
123                 oa->o_dirty = 0;
124         else if (oa->o_dirty > fed->fed_grant + 4 * FILTER_GRANT_CHUNK)
125                 oa->o_dirty = fed->fed_grant + 4 * FILTER_GRANT_CHUNK;
126         obd->u.filter.fo_tot_dirty += oa->o_dirty - fed->fed_dirty;
127         if (fed->fed_grant < oa->o_dropped) {
128                 CDEBUG(D_CACHE,"%s: cli %s/%p reports %u dropped > grant %lu\n",
129                        obd->obd_name, exp->exp_client_uuid.uuid, exp,
130                        oa->o_dropped, fed->fed_grant);
131                 oa->o_dropped = 0;
132         }
133         if (obd->u.filter.fo_tot_granted < oa->o_dropped) {
134                 CERROR("%s: cli %s/%p reports %u dropped > tot_grant "LPU64"\n",
135                        obd->obd_name, exp->exp_client_uuid.uuid, exp,
136                        oa->o_dropped, obd->u.filter.fo_tot_granted);
137                 oa->o_dropped = 0;
138         }
139         obd->u.filter.fo_tot_granted -= oa->o_dropped;
140         fed->fed_grant -= oa->o_dropped;
141         fed->fed_dirty = oa->o_dirty;
142         if (fed->fed_dirty < 0 || fed->fed_grant < 0 || fed->fed_pending < 0) {
143                 CERROR("%s: cli %s/%p dirty %ld pend %ld grant %ld\n",
144                        obd->obd_name, exp->exp_client_uuid.uuid, exp,
145                        fed->fed_dirty, fed->fed_pending, fed->fed_grant);
146                 spin_unlock(&obd->obd_osfs_lock);
147                 LBUG();
148         }
149         EXIT;
150 }
151
152 /* Figure out how much space is available between what we've granted
153  * and what remains in the filesystem.  Compensate for ext3 indirect
154  * block overhead when computing how much free space is left ungranted.
155  *
156  * Caller must hold obd_osfs_lock. */
157 obd_size filter_grant_space_left(struct obd_export *exp)
158 {
159         struct obd_device *obd = exp->exp_obd;
160         int blockbits = obd->u.obt.obt_sb->s_blocksize_bits;
161         obd_size tot_granted = obd->u.filter.fo_tot_granted, avail, left = 0;
162         int rc, statfs_done = 0;
163
164         LASSERT_SPIN_LOCKED(&obd->obd_osfs_lock);
165
166         if (cfs_time_before_64(obd->obd_osfs_age, cfs_time_current_64() - HZ)) {
167 restat:
168                 rc = fsfilt_statfs(obd, obd->u.obt.obt_sb,
169                                    cfs_time_current_64() + HZ);
170                 if (rc) /* N.B. statfs can't really fail */
171                         RETURN(0);
172                 statfs_done = 1;
173         }
174
175         avail = obd->obd_osfs.os_bavail;
176         left = avail - (avail >> (blockbits - 3)); /* (d)indirect */
177         if (left > GRANT_FOR_LLOG(obd)) {
178                 left = (left - GRANT_FOR_LLOG(obd)) << blockbits;
179         } else {
180                 left = 0 /* << blockbits */;
181         }
182
183         if (!statfs_done && left < 32 * FILTER_GRANT_CHUNK + tot_granted) {
184                 CDEBUG(D_CACHE, "fs has no space left and statfs too old\n");
185                 goto restat;
186         }
187
188         if (left >= tot_granted) {
189                 left -= tot_granted;
190         } else {
191                 if (left < tot_granted - obd->u.filter.fo_tot_pending) {
192                         CERROR("%s: cli %s/%p grant "LPU64" > available "
193                                LPU64" and pending "LPU64"\n", obd->obd_name,
194                                exp->exp_client_uuid.uuid, exp, tot_granted,
195                                left, obd->u.filter.fo_tot_pending);
196                 }
197                 left = 0;
198         }
199
200         CDEBUG(D_CACHE, "%s: cli %s/%p free: "LPU64" avail: "LPU64" grant "LPU64
201                " left: "LPU64" pending: "LPU64"\n", obd->obd_name,
202                exp->exp_client_uuid.uuid, exp,
203                obd->obd_osfs.os_bfree << blockbits, avail << blockbits,
204                tot_granted, left, obd->u.filter.fo_tot_pending);
205
206         return left;
207 }
208
209 /* Calculate how much grant space to allocate to this client, based on how
210  * much space is currently free and how much of that is already granted.
211  *
212  * Caller must hold obd_osfs_lock. */
213 long filter_grant(struct obd_export *exp, obd_size current_grant,
214                   obd_size want, obd_size fs_space_left)
215 {
216         struct obd_device *obd = exp->exp_obd;
217         struct filter_export_data *fed = &exp->exp_filter_data;
218         int blockbits = obd->u.obt.obt_sb->s_blocksize_bits;
219         __u64 grant = 0;
220
221         LASSERT_SPIN_LOCKED(&obd->obd_osfs_lock);
222
223         /* Grant some fraction of the client's requested grant space so that
224          * they are not always waiting for write credits (not all of it to
225          * avoid overgranting in face of multiple RPCs in flight).  This
226          * essentially will be able to control the OSC_MAX_RIF for a client.
227          *
228          * If we do have a large disparity between what the client thinks it
229          * has and what we think it has, don't grant very much and let the
230          * client consume its grant first.  Either it just has lots of RPCs
231          * in flight, or it was evicted and its grants will soon be used up. */
232         if (want > 0x7fffffff) {
233                 CERROR("%s: client %s/%p requesting > 2GB grant "LPU64"\n",
234                        obd->obd_name, exp->exp_client_uuid.uuid, exp, want);
235         } else if (current_grant < want &&
236                    current_grant < fed->fed_grant + FILTER_GRANT_CHUNK) {
237                 grant = min((want >> blockbits),
238                             (fs_space_left >> blockbits) / 8);
239                 grant <<= blockbits;
240
241                 if (grant) {
242                         /* Allow >FILTER_GRANT_CHUNK size when clients
243                          * reconnect due to a server reboot.
244                          */
245                         if ((grant > FILTER_GRANT_CHUNK) &&
246                             (!obd->obd_recovering))
247                                 grant = FILTER_GRANT_CHUNK;
248
249                         obd->u.filter.fo_tot_granted += grant;
250                         fed->fed_grant += grant;
251                         if (fed->fed_grant < 0) {
252                                 CERROR("%s: cli %s/%p grant %ld want "LPU64
253                                        "current"LPU64"\n",
254                                        obd->obd_name, exp->exp_client_uuid.uuid,
255                                        exp, fed->fed_grant, want,current_grant);
256                                 spin_unlock(&obd->obd_osfs_lock);
257                                 LBUG();
258                         }
259                 }
260         }
261
262         CDEBUG(D_CACHE,
263                "%s: cli %s/%p wants: "LPU64" current grant "LPU64 
264                " granting: "LPU64"\n", obd->obd_name, exp->exp_client_uuid.uuid,
265                exp, want, current_grant, grant);
266         CDEBUG(D_CACHE,
267                "%s: cli %s/%p tot cached:"LPU64" granted:"LPU64
268                " num_exports: %d\n", obd->obd_name, exp->exp_client_uuid.uuid,
269                exp, obd->u.filter.fo_tot_dirty,
270                obd->u.filter.fo_tot_granted, obd->obd_num_exports);
271
272         return grant;
273 }
274
275 static int filter_preprw_read(int cmd, struct obd_export *exp, struct obdo *oa,
276                               int objcount, struct obd_ioobj *obj,
277                               int niocount, struct niobuf_remote *nb,
278                               struct niobuf_local *res,
279                               struct obd_trans_info *oti,
280                               struct lustre_capa *capa)
281 {
282         struct obd_device *obd = exp->exp_obd;
283         struct lvfs_run_ctxt saved;
284         struct niobuf_remote *rnb;
285         struct niobuf_local *lnb;
286         struct dentry *dentry = NULL;
287         struct inode *inode;
288         void *iobuf = NULL;
289         int rc = 0, i, tot_bytes = 0;
290         unsigned long now = jiffies;
291         ENTRY;
292
293         /* We are currently not supporting multi-obj BRW_READ RPCS at all.
294          * When we do this function's dentry cleanup will need to be fixed.
295          * These values are verified in ost_brw_write() from the wire. */
296         LASSERTF(objcount == 1, "%d\n", objcount);
297         LASSERTF(obj->ioo_bufcnt > 0, "%d\n", obj->ioo_bufcnt);
298
299         rc = filter_auth_capa(exp, NULL, obdo_mdsno(oa), capa,
300                               CAPA_OPC_OSS_READ);
301         if (rc)
302                 RETURN(rc);
303
304         if (oa && oa->o_valid & OBD_MD_FLGRANT) {
305                 spin_lock(&obd->obd_osfs_lock);
306                 filter_grant_incoming(exp, oa);
307
308                 oa->o_grant = 0;
309                 spin_unlock(&obd->obd_osfs_lock);
310         }
311
312         iobuf = filter_iobuf_get(&obd->u.filter, oti);
313         if (IS_ERR(iobuf))
314                 RETURN(PTR_ERR(iobuf));
315
316         push_ctxt(&saved, &obd->obd_lvfs_ctxt, NULL);
317         dentry = filter_oa2dentry(obd, oa);
318         if (IS_ERR(dentry)) {
319                 rc = PTR_ERR(dentry);
320                 dentry = NULL;
321                 GOTO(cleanup, rc);
322         }
323
324         inode = dentry->d_inode;
325
326         obdo_to_inode(inode, oa, OBD_MD_FLATIME);
327         fsfilt_check_slow(obd, now, "preprw_read setup");
328
329         for (i = 0, lnb = res, rnb = nb; i < obj->ioo_bufcnt;
330              i++, rnb++, lnb++) {
331                 lnb->dentry = dentry;
332                 lnb->offset = rnb->offset;
333                 lnb->len    = rnb->len;
334                 lnb->flags  = rnb->flags;
335
336                 /*
337                  * ost_brw_write()->ost_nio_pages_get() already initialized
338                  * lnb->page to point to the page from the per-thread page
339                  * pool (bug 5137), initialize page.
340                  */
341                 LASSERT(lnb->page != NULL);
342
343                 if (i_size_read(inode) <= rnb->offset)
344                         /* If there's no more data, abort early.  lnb->rc == 0,
345                          * so it's easy to detect later. */
346                         break;
347                 else
348                         filter_alloc_dio_page(obd, inode, lnb);
349
350                 if (i_size_read(inode) < lnb->offset + lnb->len - 1)
351                         lnb->rc = i_size_read(inode) - lnb->offset;
352                 else
353                         lnb->rc = lnb->len;
354
355                 tot_bytes += lnb->rc;
356
357                 filter_iobuf_add_page(obd, iobuf, inode, lnb->page);
358         }
359
360         fsfilt_check_slow(obd, now, "start_page_read");
361
362         rc = filter_direct_io(OBD_BRW_READ, dentry, iobuf,
363                               exp, NULL, NULL, NULL);
364         if (rc)
365                 GOTO(cleanup, rc);
366
367         lprocfs_counter_add(obd->obd_stats, LPROC_FILTER_READ_BYTES, tot_bytes);
368
369         if (exp->exp_nid_stats && exp->exp_nid_stats->nid_stats)
370                 lprocfs_counter_add(exp->exp_nid_stats->nid_stats,
371                                     LPROC_FILTER_READ_BYTES, tot_bytes);
372
373         EXIT;
374
375  cleanup:
376         if (rc != 0) {
377                 filter_free_dio_pages(objcount, obj, niocount, res);
378
379                 if (dentry != NULL)
380                         f_dput(dentry);
381         }
382
383         filter_iobuf_put(&obd->u.filter, iobuf, oti);
384
385         pop_ctxt(&saved, &obd->obd_lvfs_ctxt, NULL);
386         if (rc)
387                 CERROR("io error %d\n", rc);
388
389         return rc;
390 }
391
392 /* When clients have dirtied as much space as they've been granted they
393  * fall through to sync writes.  These sync writes haven't been expressed
394  * in grants and need to error with ENOSPC when there isn't room in the
395  * filesystem for them after grants are taken into account.  However,
396  * writeback of the dirty data that was already granted space can write
397  * right on through.
398  *
399  * Caller must hold obd_osfs_lock. */
400 static int filter_grant_check(struct obd_export *exp, struct obdo *oa, 
401                               int objcount, struct fsfilt_objinfo *fso, 
402                               int niocount, struct niobuf_remote *rnb,
403                               struct niobuf_local *lnb, obd_size *left,
404                               struct inode *inode)
405 {
406         struct filter_export_data *fed = &exp->exp_filter_data;
407         int blocksize = exp->exp_obd->u.obt.obt_sb->s_blocksize;
408         unsigned long used = 0, ungranted = 0, using;
409         int i, rc = -ENOSPC, obj, n = 0;
410
411         LASSERT_SPIN_LOCKED(&exp->exp_obd->obd_osfs_lock);
412
413         for (obj = 0; obj < objcount; obj++) {
414                 for (i = 0; i < fso[obj].fso_bufcnt; i++, n++) {
415                         int tmp, bytes;
416
417                         /* should match the code in osc_exit_cache */
418                         bytes = rnb[n].len;
419                         bytes += rnb[n].offset & (blocksize - 1);
420                         tmp = (rnb[n].offset + rnb[n].len) & (blocksize - 1);
421                         if (tmp)
422                                 bytes += blocksize - tmp;
423
424                         if ((rnb[n].flags & OBD_BRW_FROM_GRANT) &&
425                             (oa->o_valid & OBD_MD_FLGRANT)) {
426                                 if (fed->fed_grant < used + bytes) {
427                                         CDEBUG(D_CACHE,
428                                                "%s: cli %s/%p claims %ld+%d "
429                                                "GRANT, real grant %lu idx %d\n",
430                                                exp->exp_obd->obd_name,
431                                                exp->exp_client_uuid.uuid, exp,
432                                                used, bytes, fed->fed_grant, n);
433                                 } else {
434                                         used += bytes;
435                                         rnb[n].flags |= OBD_BRW_GRANTED;
436                                         lnb[n].lnb_grant_used = bytes;
437                                         CDEBUG(0, "idx %d used=%lu\n", n, used);
438                                         rc = 0;
439                                         continue;
440                                 }
441                         }
442                         if (*left > ungranted + bytes) {
443                                 /* if enough space, pretend it was granted */
444                                 ungranted += bytes;
445                                 rnb[n].flags |= OBD_BRW_GRANTED;
446                                 lnb[n].lnb_grant_used = bytes;
447                                 CDEBUG(0, "idx %d ungranted=%lu\n",n,ungranted);
448                                 rc = 0;
449                                 continue;
450                         }
451
452                         /* We can't check for already-mapped blocks here, as
453                          * it requires dropping the osfs lock to do the bmap.
454                          * Instead, we return ENOSPC and in that case we need
455                          * to go through and verify if all of the blocks not
456                          * marked BRW_GRANTED are already mapped and we can
457                          * ignore this error. */
458                         lnb[n].rc = -ENOSPC;
459                         rnb[n].flags &= ~OBD_BRW_GRANTED;
460                         CDEBUG(D_CACHE,"%s: cli %s/%p idx %d no space for %d\n",
461                                exp->exp_obd->obd_name,
462                                exp->exp_client_uuid.uuid, exp, n, bytes);
463                 }
464         }
465
466         /* Now substract what client have used already.  We don't subtract
467          * this from the tot_granted yet, so that other client's can't grab
468          * that space before we have actually allocated our blocks.  That
469          * happens in filter_grant_commit() after the writes are done. */
470         *left -= ungranted;
471         fed->fed_grant -= used;
472         fed->fed_pending += used + ungranted;
473         exp->exp_obd->u.filter.fo_tot_granted += ungranted;
474         exp->exp_obd->u.filter.fo_tot_pending += used + ungranted;
475
476         CDEBUG(D_CACHE,
477                "%s: cli %s/%p used: %lu ungranted: %lu grant: %lu dirty: %lu\n",
478                exp->exp_obd->obd_name, exp->exp_client_uuid.uuid, exp, used,
479                ungranted, fed->fed_grant, fed->fed_dirty);
480
481         /* Rough calc in case we don't refresh cached statfs data */
482         using = (used + ungranted + 1 ) >>
483                 exp->exp_obd->u.obt.obt_sb->s_blocksize_bits;
484         if (exp->exp_obd->obd_osfs.os_bavail > using)
485                 exp->exp_obd->obd_osfs.os_bavail -= using;
486         else
487                 exp->exp_obd->obd_osfs.os_bavail = 0;
488
489         if (fed->fed_dirty < used) {
490                 CERROR("%s: cli %s/%p claims used %lu > fed_dirty %lu\n",
491                        exp->exp_obd->obd_name, exp->exp_client_uuid.uuid, exp,
492                        used, fed->fed_dirty);
493                 used = fed->fed_dirty;
494         }
495         exp->exp_obd->u.filter.fo_tot_dirty -= used;
496         fed->fed_dirty -= used;
497
498         if (fed->fed_dirty < 0 || fed->fed_grant < 0 || fed->fed_pending < 0) {
499                 CERROR("%s: cli %s/%p dirty %ld pend %ld grant %ld\n",
500                        exp->exp_obd->obd_name, exp->exp_client_uuid.uuid, exp,
501                        fed->fed_dirty, fed->fed_pending, fed->fed_grant);
502                 spin_unlock(&exp->exp_obd->obd_osfs_lock);
503                 LBUG();
504         }
505         return rc;
506 }
507
508 /* If we ever start to support multi-object BRW RPCs, we will need to get locks
509  * on mulitple inodes.  That isn't all, because there still exists the
510  * possibility of a truncate starting a new transaction while holding the ext3
511  * rwsem = write while some writes (which have started their transactions here)
512  * blocking on the ext3 rwsem = read => lock inversion.
513  *
514  * The handling gets very ugly when dealing with locked pages.  It may be easier
515  * to just get rid of the locked page code (which has problems of its own) and
516  * either discover we do not need it anymore (i.e. it was a symptom of another
517  * bug) or ensure we get the page locks in an appropriate order. */
518 static int filter_preprw_write(int cmd, struct obd_export *exp, struct obdo *oa,
519                                int objcount, struct obd_ioobj *obj,
520                                int niocount, struct niobuf_remote *nb,
521                                struct niobuf_local *res,
522                                struct obd_trans_info *oti,
523                                struct lustre_capa *capa)
524 {
525         struct lvfs_run_ctxt saved;
526         struct niobuf_remote *rnb;
527         struct niobuf_local *lnb = res;
528         struct fsfilt_objinfo fso;
529         struct filter_mod_data *fmd;
530         struct dentry *dentry = NULL;
531         void *iobuf;
532         obd_size left;
533         unsigned long now = jiffies;
534         int rc = 0, i, tot_bytes = 0, cleanup_phase = 0;
535         ENTRY;
536         LASSERT(objcount == 1);
537         LASSERT(obj->ioo_bufcnt > 0);
538
539         rc = filter_auth_capa(exp, NULL, obdo_mdsno(oa), capa,
540                               CAPA_OPC_OSS_WRITE);
541         if (rc)
542                 RETURN(rc);
543
544         push_ctxt(&saved, &exp->exp_obd->obd_lvfs_ctxt, NULL);
545         iobuf = filter_iobuf_get(&exp->exp_obd->u.filter, oti);
546         if (IS_ERR(iobuf))
547                 GOTO(cleanup, rc = PTR_ERR(iobuf));
548         cleanup_phase = 1;
549
550         dentry = filter_fid2dentry(exp->exp_obd, NULL, obj->ioo_gr,
551                                    obj->ioo_id);
552         if (IS_ERR(dentry))
553                 GOTO(cleanup, rc = PTR_ERR(dentry));
554         cleanup_phase = 2;
555
556         if (dentry->d_inode == NULL) {
557                 CERROR("%s: trying to BRW to non-existent file "LPU64"\n",
558                        exp->exp_obd->obd_name, obj->ioo_id);
559                 GOTO(cleanup, rc = -ENOENT);
560         }
561
562         fso.fso_dentry = dentry;
563         fso.fso_bufcnt = obj->ioo_bufcnt;
564
565         fsfilt_check_slow(exp->exp_obd, now, "preprw_write setup");
566
567         /* Don't update inode timestamps if this write is older than a
568          * setattr which modifies the timestamps. b=10150 */
569         /* XXX when we start having persistent reservations this needs to
570          * be changed to filter_fmd_get() to create the fmd if it doesn't
571          * already exist so we can store the reservation handle there. */
572         fmd = filter_fmd_find(exp, obj->ioo_id, obj->ioo_gr);
573
574         LASSERT(oa != NULL);
575         spin_lock(&exp->exp_obd->obd_osfs_lock);
576         filter_grant_incoming(exp, oa);
577         if (fmd && fmd->fmd_mactime_xid > oti->oti_xid)
578                 oa->o_valid &= ~(OBD_MD_FLMTIME | OBD_MD_FLCTIME |
579                                  OBD_MD_FLATIME);
580         else
581                 obdo_to_inode(dentry->d_inode, oa, OBD_MD_FLATIME |
582                               OBD_MD_FLMTIME | OBD_MD_FLCTIME);
583         cleanup_phase = 3;
584
585         left = filter_grant_space_left(exp);
586
587         rc = filter_grant_check(exp, oa, objcount, &fso, niocount, nb, res,
588                                 &left, dentry->d_inode);
589
590         /* do not zero out oa->o_valid as it is used in filter_commitrw_write()
591          * for setting UID/GID and fid EA in first write time. */
592         if (oa->o_valid & OBD_MD_FLGRANT)
593                 oa->o_grant = filter_grant(exp,oa->o_grant,oa->o_undirty,left);
594
595         spin_unlock(&exp->exp_obd->obd_osfs_lock);
596         filter_fmd_put(exp, fmd);
597
598         if (rc)
599                 GOTO(cleanup, rc);
600
601         for (i = 0, rnb = nb, lnb = res; i < obj->ioo_bufcnt;
602              i++, lnb++, rnb++) {
603                 /* We still set up for ungranted pages so that granted pages
604                  * can be written to disk as they were promised, and portals
605                  * needs to keep the pages all aligned properly. */
606                 lnb->dentry = dentry;
607                 lnb->offset = rnb->offset;
608                 lnb->len    = rnb->len;
609                 lnb->flags  = rnb->flags;
610
611                 /*
612                  * ost_brw_write()->ost_nio_pages_get() already initialized
613                  * lnb->page to point to the page from the per-thread page
614                  * pool (bug 5137), initialize page.
615                  */
616                 LASSERT(lnb->page != NULL);
617                 if (lnb->len != CFS_PAGE_SIZE) {
618                         memset(kmap(lnb->page) + lnb->len,
619                                0, CFS_PAGE_SIZE - lnb->len);
620                         kunmap(lnb->page);
621                 }
622                 lnb->page->index = lnb->offset >> CFS_PAGE_SHIFT;
623
624                 cleanup_phase = 4;
625
626                 /* If the filter writes a partial page, then has the file
627                  * extended, the client will read in the whole page.  the
628                  * filter has to be careful to zero the rest of the partial
629                  * page on disk.  we do it by hand for partial extending
630                  * writes, send_bio() is responsible for zeroing pages when
631                  * asked to read unmapped blocks -- brw_kiovec() does this. */
632                 if (lnb->len != CFS_PAGE_SIZE) {
633                         __s64 maxidx;
634
635                         maxidx = ((i_size_read(dentry->d_inode) +
636                                    CFS_PAGE_SIZE - 1) >> CFS_PAGE_SHIFT) - 1;
637                         if (maxidx >= lnb->page->index) {
638                                 LL_CDEBUG_PAGE(D_PAGE, lnb->page, "write %u @ "
639                                                LPU64" flg %x before EOF %llu\n",
640                                                lnb->len, lnb->offset,lnb->flags,
641                                                i_size_read(dentry->d_inode));
642                                 filter_iobuf_add_page(exp->exp_obd, iobuf,
643                                                       dentry->d_inode,
644                                                       lnb->page);
645                         } else {
646                                 long off;
647                                 char *p = kmap(lnb->page);
648
649                                 off = lnb->offset & ~CFS_PAGE_MASK;
650                                 if (off)
651                                         memset(p, 0, off);
652                                 off = (lnb->offset + lnb->len) & ~CFS_PAGE_MASK;
653                                 if (off)
654                                         memset(p + off, 0, CFS_PAGE_SIZE - off);
655                                 kunmap(lnb->page);
656                         }
657                 }
658                 if (lnb->rc == 0)
659                         tot_bytes += lnb->len;
660         }
661
662         rc = filter_direct_io(OBD_BRW_READ, dentry, iobuf, exp,
663                               NULL, NULL, NULL);
664
665         fsfilt_check_slow(exp->exp_obd, now, "start_page_write");
666
667         if (exp->exp_nid_stats && exp->exp_nid_stats->nid_stats)
668                 lprocfs_counter_add(exp->exp_nid_stats->nid_stats,
669                                     LPROC_FILTER_WRITE_BYTES, tot_bytes);
670         EXIT;
671 cleanup:
672         switch(cleanup_phase) {
673         case 4:
674         case 3:
675                 filter_iobuf_put(&exp->exp_obd->u.filter, iobuf, oti);
676         case 2:
677                 pop_ctxt(&saved, &exp->exp_obd->obd_lvfs_ctxt, NULL);
678                 if (rc)
679                         f_dput(dentry);
680                 break;
681         case 1:
682                 filter_iobuf_put(&exp->exp_obd->u.filter, iobuf, oti);
683         case 0:
684                 spin_lock(&exp->exp_obd->obd_osfs_lock);
685                 if (oa)
686                         filter_grant_incoming(exp, oa);
687                 spin_unlock(&exp->exp_obd->obd_osfs_lock);
688                 pop_ctxt(&saved, &exp->exp_obd->obd_lvfs_ctxt, NULL);
689                 break;
690         default:;
691         }
692         return rc;
693 }
694
695 int filter_preprw(int cmd, struct obd_export *exp, struct obdo *oa,
696                   int objcount, struct obd_ioobj *obj, int niocount,
697                   struct niobuf_remote *nb, struct niobuf_local *res,
698                   struct obd_trans_info *oti, struct lustre_capa *capa)
699 {
700         if (cmd == OBD_BRW_WRITE)
701                 return filter_preprw_write(cmd, exp, oa, objcount, obj,
702                                            niocount, nb, res, oti, capa);
703         if (cmd == OBD_BRW_READ)
704                 return filter_preprw_read(cmd, exp, oa, objcount, obj,
705                                           niocount, nb, res, oti, capa);
706         LBUG();
707         return -EPROTO;
708 }
709
710 void filter_release_read_page(struct filter_obd *filter, struct inode *inode,
711                               struct page *page)
712 {
713         int drop = 0;
714
715         if (inode != NULL &&
716             (i_size_read(inode) > filter->fo_readcache_max_filesize))
717                 drop = 1;
718
719         /* drop from cache like truncate_list_pages() */
720         if (drop && !TryLockPage(page)) {
721                 if (page->mapping)
722                         ll_truncate_complete_page(page);
723                 unlock_page(page);
724         }
725         page_cache_release(page);
726 }
727
728 static int filter_commitrw_read(struct obd_export *exp, struct obdo *oa,
729                                 int objcount, struct obd_ioobj *obj,
730                                 int niocount, struct niobuf_local *res,
731                                 struct obd_trans_info *oti, int rc)
732 {
733         struct inode *inode = NULL;
734         struct ldlm_res_id res_id;
735         struct ldlm_resource *resource = NULL;
736         struct ldlm_namespace *ns = exp->exp_obd->obd_namespace;
737         ENTRY;
738
739         osc_build_res_name(obj->ioo_id, obj->ioo_gr, &res_id);
740         /* If oa != NULL then filter_preprw_read updated the inode atime
741          * and we should update the lvb so that other glimpses will also
742          * get the updated value. bug 5972 */
743         if (oa && ns && ns->ns_lvbo && ns->ns_lvbo->lvbo_update) {
744                 resource = ldlm_resource_get(ns, NULL, &res_id, LDLM_EXTENT, 0);
745
746                 if (resource != NULL) {
747                         ns->ns_lvbo->lvbo_update(resource, NULL, 0, 1);
748                         ldlm_resource_putref(resource);
749                 }
750         }
751
752         if (res->dentry != NULL)
753                 inode = res->dentry->d_inode;
754
755         filter_free_dio_pages(objcount, obj, niocount, res);
756
757         if (res->dentry != NULL)
758                 f_dput(res->dentry);
759         RETURN(rc);
760 }
761
762 void flip_into_page_cache(struct inode *inode, struct page *new_page)
763 {
764         struct page *old_page;
765         int rc;
766
767         do {
768                 /* the dlm is protecting us from read/write concurrency, so we
769                  * expect this find_lock_page to return quickly.  even if we
770                  * race with another writer it won't be doing much work with
771                  * the page locked.  we do this 'cause t_c_p expects a
772                  * locked page, and it wants to grab the pagecache lock
773                  * as well. */
774                 old_page = find_lock_page(inode->i_mapping, new_page->index);
775                 if (old_page) {
776                         ll_truncate_complete_page(old_page);
777                         unlock_page(old_page);
778                         page_cache_release(old_page);
779                 }
780
781 #if 0 /* this should be a /proc tunable someday */
782                 /* racing o_directs (no locking ioctl) could race adding
783                  * their pages, so we repeat the page invalidation unless
784                  * we successfully added our new page */
785                 rc = add_to_page_cache_unique(new_page, inode->i_mapping,
786                                               new_page->index,
787                                               page_hash(inode->i_mapping,
788                                                         new_page->index));
789                 if (rc == 0) {
790                         /* add_to_page_cache clears uptodate|dirty and locks
791                          * the page */
792                         SetPageUptodate(new_page);
793                         unlock_page(new_page);
794                 }
795 #else
796                 rc = 0;
797 #endif
798         } while (rc != 0);
799 }
800
801 void filter_grant_commit(struct obd_export *exp, int niocount,
802                          struct niobuf_local *res)
803 {
804         struct filter_obd *filter = &exp->exp_obd->u.filter;
805         struct niobuf_local *lnb = res;
806         unsigned long pending = 0;
807         int i;
808
809         spin_lock(&exp->exp_obd->obd_osfs_lock);
810         for (i = 0, lnb = res; i < niocount; i++, lnb++)
811                 pending += lnb->lnb_grant_used;
812
813         LASSERTF(exp->exp_filter_data.fed_pending >= pending,
814                  "%s: cli %s/%p fed_pending: %lu grant_used: %lu\n",
815                  exp->exp_obd->obd_name, exp->exp_client_uuid.uuid, exp,
816                  exp->exp_filter_data.fed_pending, pending);
817         exp->exp_filter_data.fed_pending -= pending;
818         LASSERTF(filter->fo_tot_granted >= pending,
819                  "%s: cli %s/%p tot_granted: "LPU64" grant_used: %lu\n",
820                  exp->exp_obd->obd_name, exp->exp_client_uuid.uuid, exp,
821                  exp->exp_obd->u.filter.fo_tot_granted, pending);
822         filter->fo_tot_granted -= pending;
823         LASSERTF(filter->fo_tot_pending >= pending,
824                  "%s: cli %s/%p tot_pending: "LPU64" grant_used: %lu\n",
825                  exp->exp_obd->obd_name, exp->exp_client_uuid.uuid, exp,
826                  filter->fo_tot_pending, pending);
827         filter->fo_tot_pending -= pending;
828
829         spin_unlock(&exp->exp_obd->obd_osfs_lock);
830 }
831
832 int filter_commitrw(int cmd, struct obd_export *exp, struct obdo *oa,
833                     int objcount, struct obd_ioobj *obj, int niocount,
834                     struct niobuf_local *res, struct obd_trans_info *oti,
835                     int rc)
836 {
837         if (cmd == OBD_BRW_WRITE)
838                 return filter_commitrw_write(exp, oa, objcount, obj, niocount,
839                                              res, oti, rc);
840         if (cmd == OBD_BRW_READ)
841                 return filter_commitrw_read(exp, oa, objcount, obj, niocount,
842                                             res, oti, rc);
843         LBUG();
844         return -EPROTO;
845 }
846
847 int filter_brw(int cmd, struct obd_export *exp, struct obd_info *oinfo,
848                obd_count oa_bufs, struct brw_page *pga,
849                struct obd_trans_info *oti)
850 {
851         struct obd_ioobj ioo;
852         struct niobuf_local *lnb;
853         struct niobuf_remote *rnb;
854         obd_count i;
855         int ret = 0;
856         ENTRY;
857
858         OBD_ALLOC(lnb, oa_bufs * sizeof(struct niobuf_local));
859         OBD_ALLOC(rnb, oa_bufs * sizeof(struct niobuf_remote));
860
861         if (lnb == NULL || rnb == NULL)
862                 GOTO(out, ret = -ENOMEM);
863
864         for (i = 0; i < oa_bufs; i++) {
865                 lnb[i].page = pga[i].pg;
866                 rnb[i].offset = pga[i].off;
867                 rnb[i].len = pga[i].count;
868         }
869
870         obdo_to_ioobj(oinfo->oi_oa, &ioo);
871         ioo.ioo_bufcnt = oa_bufs;
872
873         ret = filter_preprw(cmd, exp, oinfo->oi_oa, 1, &ioo,
874                             oa_bufs, rnb, lnb, oti, oinfo_capa(oinfo));
875         if (ret != 0)
876                 GOTO(out, ret);
877
878         ret = filter_commitrw(cmd, exp, oinfo->oi_oa, 1, &ioo,
879                               oa_bufs, lnb, oti, ret);
880
881 out:
882         if (lnb)
883                 OBD_FREE(lnb, oa_bufs * sizeof(struct niobuf_local));
884         if (rnb)
885                 OBD_FREE(rnb, oa_bufs * sizeof(struct niobuf_remote));
886         RETURN(ret);
887 }