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[fs/lustre-release.git] / lustre / osd-ldiskfs / osd_io.c
1 /*
2  * GPL HEADER START
3  *
4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 only,
8  * as published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope that it will be useful, but
11  * WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13  * General Public License version 2 for more details (a copy is included
14  * in the LICENSE file that accompanied this code).
15  *
16  * You should have received a copy of the GNU General Public License
17  * version 2 along with this program; If not, see
18  * http://www.gnu.org/licenses/gpl-2.0.html
19  *
20  * GPL HEADER END
21  */
22 /*
23  * Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved.
24  * Use is subject to license terms.
25  *
26  * Copyright (c) 2012, 2016, Intel Corporation.
27  */
28 /*
29  * This file is part of Lustre, http://www.lustre.org/
30  * Lustre is a trademark of Sun Microsystems, Inc.
31  *
32  * lustre/osd/osd_io.c
33  *
34  * body operations
35  *
36  * Author: Nikita Danilov <nikita@clusterfs.com>
37  * Author: Alex Zhuravlev <bzzz@whamcloud.com>
38  *
39  */
40
41 /* LUSTRE_VERSION_CODE */
42 #include <lustre_ver.h>
43 /* prerequisite for linux/xattr.h */
44 #include <linux/types.h>
45 /* prerequisite for linux/xattr.h */
46 #include <linux/fs.h>
47
48 /*
49  * struct OBD_{ALLOC,FREE}*()
50  * OBD_FAIL_CHECK
51  */
52 #include <obd_support.h>
53
54 #include "osd_internal.h"
55
56 /* ext_depth() */
57 #include <ldiskfs/ldiskfs_extents.h>
58
59 static int __osd_init_iobuf(struct osd_device *d, struct osd_iobuf *iobuf,
60                             int rw, int line, int pages)
61 {
62         int blocks, i;
63
64         LASSERTF(iobuf->dr_elapsed_valid == 0,
65                  "iobuf %p, reqs %d, rw %d, line %d\n", iobuf,
66                  atomic_read(&iobuf->dr_numreqs), iobuf->dr_rw,
67                  iobuf->dr_init_at);
68         LASSERT(pages <= PTLRPC_MAX_BRW_PAGES);
69
70         init_waitqueue_head(&iobuf->dr_wait);
71         atomic_set(&iobuf->dr_numreqs, 0);
72         iobuf->dr_npages = 0;
73         iobuf->dr_error = 0;
74         iobuf->dr_dev = d;
75         iobuf->dr_frags = 0;
76         iobuf->dr_elapsed = 0;
77         /* must be counted before, so assert */
78         iobuf->dr_rw = rw;
79         iobuf->dr_init_at = line;
80
81         blocks = pages * (PAGE_SIZE >> osd_sb(d)->s_blocksize_bits);
82         if (iobuf->dr_bl_buf.lb_len >= blocks * sizeof(iobuf->dr_blocks[0])) {
83                 LASSERT(iobuf->dr_pg_buf.lb_len >=
84                         pages * sizeof(iobuf->dr_pages[0]));
85                 return 0;
86         }
87
88         /* start with 1MB for 4K blocks */
89         i = 256;
90         while (i <= PTLRPC_MAX_BRW_PAGES && i < pages)
91                 i <<= 1;
92
93         CDEBUG(D_OTHER, "realloc %u for %u (%u) pages\n",
94                (unsigned)(pages * sizeof(iobuf->dr_pages[0])), i, pages);
95         pages = i;
96         blocks = pages * (PAGE_SIZE >> osd_sb(d)->s_blocksize_bits);
97         iobuf->dr_max_pages = 0;
98         CDEBUG(D_OTHER, "realloc %u for %u blocks\n",
99                (unsigned)(blocks * sizeof(iobuf->dr_blocks[0])), blocks);
100
101         lu_buf_realloc(&iobuf->dr_bl_buf, blocks * sizeof(iobuf->dr_blocks[0]));
102         iobuf->dr_blocks = iobuf->dr_bl_buf.lb_buf;
103         if (unlikely(iobuf->dr_blocks == NULL))
104                 return -ENOMEM;
105
106         lu_buf_realloc(&iobuf->dr_pg_buf, pages * sizeof(iobuf->dr_pages[0]));
107         iobuf->dr_pages = iobuf->dr_pg_buf.lb_buf;
108         if (unlikely(iobuf->dr_pages == NULL))
109                 return -ENOMEM;
110
111         iobuf->dr_max_pages = pages;
112
113         return 0;
114 }
115 #define osd_init_iobuf(dev, iobuf, rw, pages) \
116         __osd_init_iobuf(dev, iobuf, rw, __LINE__, pages)
117
118 static void osd_iobuf_add_page(struct osd_iobuf *iobuf, struct page *page)
119 {
120         LASSERT(iobuf->dr_npages < iobuf->dr_max_pages);
121         iobuf->dr_pages[iobuf->dr_npages++] = page;
122 }
123
124 void osd_fini_iobuf(struct osd_device *d, struct osd_iobuf *iobuf)
125 {
126         int rw = iobuf->dr_rw;
127
128         if (iobuf->dr_elapsed_valid) {
129                 iobuf->dr_elapsed_valid = 0;
130                 LASSERT(iobuf->dr_dev == d);
131                 LASSERT(iobuf->dr_frags > 0);
132                 lprocfs_oh_tally(&d->od_brw_stats.
133                                  hist[BRW_R_DIO_FRAGS+rw],
134                                  iobuf->dr_frags);
135                 lprocfs_oh_tally_log2(&d->od_brw_stats.hist[BRW_R_IO_TIME+rw],
136                                       iobuf->dr_elapsed);
137         }
138 }
139
140 #ifndef REQ_WRITE /* pre-2.6.35 */
141 #define __REQ_WRITE BIO_RW
142 #endif
143
144 #ifdef HAVE_BIO_ENDIO_USES_ONE_ARG
145 static void dio_complete_routine(struct bio *bio)
146 {
147         int error = bio->bi_error;
148 #else
149 static void dio_complete_routine(struct bio *bio, int error)
150 {
151 #endif
152         struct osd_iobuf *iobuf = bio->bi_private;
153         int iter;
154         struct bio_vec *bvl;
155
156         /* CAVEAT EMPTOR: possibly in IRQ context
157          * DO NOT record procfs stats here!!! */
158
159         if (unlikely(iobuf == NULL)) {
160                 CERROR("***** bio->bi_private is NULL!  This should never "
161                        "happen.  Normally, I would crash here, but instead I "
162                        "will dump the bio contents to the console.  Please "
163                        "report this to <https://jira.hpdd.intel.com/> , along "
164                        "with any interesting messages leading up to this point "
165                        "(like SCSI errors, perhaps).  Because bi_private is "
166                        "NULL, I can't wake up the thread that initiated this "
167                        "IO - you will probably have to reboot this node.\n");
168                 CERROR("bi_next: %p, bi_flags: %lx, bi_rw: %lu, bi_vcnt: %d, "
169                        "bi_idx: %d, bi->size: %d, bi_end_io: %p, bi_cnt: %d, "
170                        "bi_private: %p\n", bio->bi_next,
171                         (unsigned long)bio->bi_flags,
172                         bio->bi_rw, bio->bi_vcnt, bio_idx(bio),
173                         bio_sectors(bio) << 9, bio->bi_end_io,
174 #ifdef HAVE_BI_CNT
175                         atomic_read(&bio->bi_cnt),
176 #else
177                         atomic_read(&bio->__bi_cnt),
178 #endif
179                         bio->bi_private);
180                 return;
181         }
182
183         /* the check is outside of the cycle for performance reason -bzzz */
184         if (!test_bit(__REQ_WRITE, &bio->bi_rw)) {
185                 bio_for_each_segment_all(bvl, bio, iter) {
186                         if (likely(error == 0))
187                                 SetPageUptodate(bvl_to_page(bvl));
188                         LASSERT(PageLocked(bvl_to_page(bvl)));
189                 }
190                 atomic_dec(&iobuf->dr_dev->od_r_in_flight);
191         } else {
192                 atomic_dec(&iobuf->dr_dev->od_w_in_flight);
193         }
194
195         /* any real error is good enough -bzzz */
196         if (error != 0 && iobuf->dr_error == 0)
197                 iobuf->dr_error = error;
198
199         /*
200          * set dr_elapsed before dr_numreqs turns to 0, otherwise
201          * it's possible that service thread will see dr_numreqs
202          * is zero, but dr_elapsed is not set yet, leading to lost
203          * data in this processing and an assertion in a subsequent
204          * call to OSD.
205          */
206         if (atomic_read(&iobuf->dr_numreqs) == 1) {
207                 iobuf->dr_elapsed = jiffies - iobuf->dr_start_time;
208                 iobuf->dr_elapsed_valid = 1;
209         }
210         if (atomic_dec_and_test(&iobuf->dr_numreqs))
211                 wake_up(&iobuf->dr_wait);
212
213         /* Completed bios used to be chained off iobuf->dr_bios and freed in
214          * filter_clear_dreq().  It was then possible to exhaust the biovec-256
215          * mempool when serious on-disk fragmentation was encountered,
216          * deadlocking the OST.  The bios are now released as soon as complete
217          * so the pool cannot be exhausted while IOs are competing. bug 10076 */
218         bio_put(bio);
219 }
220
221 static void record_start_io(struct osd_iobuf *iobuf, int size)
222 {
223         struct osd_device    *osd = iobuf->dr_dev;
224         struct obd_histogram *h = osd->od_brw_stats.hist;
225
226         iobuf->dr_frags++;
227         atomic_inc(&iobuf->dr_numreqs);
228
229         if (iobuf->dr_rw == 0) {
230                 atomic_inc(&osd->od_r_in_flight);
231                 lprocfs_oh_tally(&h[BRW_R_RPC_HIST],
232                                  atomic_read(&osd->od_r_in_flight));
233                 lprocfs_oh_tally_log2(&h[BRW_R_DISK_IOSIZE], size);
234         } else if (iobuf->dr_rw == 1) {
235                 atomic_inc(&osd->od_w_in_flight);
236                 lprocfs_oh_tally(&h[BRW_W_RPC_HIST],
237                                  atomic_read(&osd->od_w_in_flight));
238                 lprocfs_oh_tally_log2(&h[BRW_W_DISK_IOSIZE], size);
239         } else {
240                 LBUG();
241         }
242 }
243
244 static void osd_submit_bio(int rw, struct bio *bio)
245 {
246         LASSERTF(rw == 0 || rw == 1, "%x\n", rw);
247         if (rw == 0)
248                 submit_bio(READ, bio);
249         else
250                 submit_bio(WRITE, bio);
251 }
252
253 static int can_be_merged(struct bio *bio, sector_t sector)
254 {
255         if (bio == NULL)
256                 return 0;
257
258         return bio_end_sector(bio) == sector ? 1 : 0;
259 }
260
261 static int osd_do_bio(struct osd_device *osd, struct inode *inode,
262                       struct osd_iobuf *iobuf)
263 {
264         int            blocks_per_page = PAGE_SIZE >> inode->i_blkbits;
265         struct page  **pages = iobuf->dr_pages;
266         int            npages = iobuf->dr_npages;
267         sector_t      *blocks = iobuf->dr_blocks;
268         int            total_blocks = npages * blocks_per_page;
269         int            sector_bits = inode->i_sb->s_blocksize_bits - 9;
270         unsigned int   blocksize = inode->i_sb->s_blocksize;
271         struct bio    *bio = NULL;
272         struct page   *page;
273         unsigned int   page_offset;
274         sector_t       sector;
275         int            nblocks;
276         int            block_idx;
277         int            page_idx;
278         int            i;
279         int            rc = 0;
280         ENTRY;
281
282         LASSERT(iobuf->dr_npages == npages);
283
284         osd_brw_stats_update(osd, iobuf);
285         iobuf->dr_start_time = cfs_time_current();
286
287         for (page_idx = 0, block_idx = 0;
288              page_idx < npages;
289              page_idx++, block_idx += blocks_per_page) {
290
291                 page = pages[page_idx];
292                 LASSERT(block_idx + blocks_per_page <= total_blocks);
293
294                 for (i = 0, page_offset = 0;
295                      i < blocks_per_page;
296                      i += nblocks, page_offset += blocksize * nblocks) {
297
298                         nblocks = 1;
299
300                         if (blocks[block_idx + i] == 0) {  /* hole */
301                                 LASSERTF(iobuf->dr_rw == 0,
302                                          "page_idx %u, block_idx %u, i %u\n",
303                                          page_idx, block_idx, i);
304                                 memset(kmap(page) + page_offset, 0, blocksize);
305                                 kunmap(page);
306                                 continue;
307                         }
308
309                         sector = (sector_t)blocks[block_idx + i] << sector_bits;
310
311                         /* Additional contiguous file blocks? */
312                         while (i + nblocks < blocks_per_page &&
313                                (sector + (nblocks << sector_bits)) ==
314                                ((sector_t)blocks[block_idx + i + nblocks] <<
315                                 sector_bits))
316                                 nblocks++;
317
318                         if (bio != NULL &&
319                             can_be_merged(bio, sector) &&
320                             bio_add_page(bio, page,
321                                          blocksize * nblocks, page_offset) != 0)
322                                 continue;       /* added this frag OK */
323
324                         if (bio != NULL) {
325                                 struct request_queue *q =
326                                         bdev_get_queue(bio->bi_bdev);
327                                 unsigned int bi_size = bio_sectors(bio) << 9;
328
329                                 /* Dang! I have to fragment this I/O */
330                                 CDEBUG(D_INODE, "bio++ sz %d vcnt %d(%d) "
331                                        "sectors %d(%d) psg %d(%d) hsg %d(%d)\n",
332                                        bi_size, bio->bi_vcnt, bio->bi_max_vecs,
333                                        bio_sectors(bio),
334                                        queue_max_sectors(q),
335                                        bio_phys_segments(q, bio),
336                                        queue_max_phys_segments(q),
337                                        0, queue_max_hw_segments(q));
338                                 record_start_io(iobuf, bi_size);
339                                 osd_submit_bio(iobuf->dr_rw, bio);
340                         }
341
342                         /* allocate new bio */
343                         bio = bio_alloc(GFP_NOIO, min(BIO_MAX_PAGES,
344                                                       (npages - page_idx) *
345                                                       blocks_per_page));
346                         if (bio == NULL) {
347                                 CERROR("Can't allocate bio %u*%u = %u pages\n",
348                                        (npages - page_idx), blocks_per_page,
349                                        (npages - page_idx) * blocks_per_page);
350                                 rc = -ENOMEM;
351                                 goto out;
352                         }
353
354                         bio->bi_bdev = inode->i_sb->s_bdev;
355                         bio_set_sector(bio, sector);
356                         bio->bi_rw = (iobuf->dr_rw == 0) ? READ : WRITE;
357                         bio->bi_end_io = dio_complete_routine;
358                         bio->bi_private = iobuf;
359
360                         rc = bio_add_page(bio, page,
361                                           blocksize * nblocks, page_offset);
362                         LASSERT(rc != 0);
363                 }
364         }
365
366         if (bio != NULL) {
367                 record_start_io(iobuf, bio_sectors(bio) << 9);
368                 osd_submit_bio(iobuf->dr_rw, bio);
369                 rc = 0;
370         }
371
372 out:
373         /* in order to achieve better IO throughput, we don't wait for writes
374          * completion here. instead we proceed with transaction commit in
375          * parallel and wait for IO completion once transaction is stopped
376          * see osd_trans_stop() for more details -bzzz */
377         if (iobuf->dr_rw == 0) {
378                 wait_event(iobuf->dr_wait,
379                            atomic_read(&iobuf->dr_numreqs) == 0);
380                 osd_fini_iobuf(osd, iobuf);
381         }
382
383         if (rc == 0)
384                 rc = iobuf->dr_error;
385         RETURN(rc);
386 }
387
388 static int osd_map_remote_to_local(loff_t offset, ssize_t len, int *nrpages,
389                                    struct niobuf_local *lnb)
390 {
391         ENTRY;
392
393         *nrpages = 0;
394
395         while (len > 0) {
396                 int poff = offset & (PAGE_SIZE - 1);
397                 int plen = PAGE_SIZE - poff;
398
399                 if (plen > len)
400                         plen = len;
401                 lnb->lnb_file_offset = offset;
402                 lnb->lnb_page_offset = poff;
403                 lnb->lnb_len = plen;
404                 /* lnb->lnb_flags = rnb->rnb_flags; */
405                 lnb->lnb_flags = 0;
406                 lnb->lnb_page = NULL;
407                 lnb->lnb_rc = 0;
408
409                 LASSERTF(plen <= len, "plen %u, len %lld\n", plen,
410                          (long long) len);
411                 offset += plen;
412                 len -= plen;
413                 lnb++;
414                 (*nrpages)++;
415         }
416
417         RETURN(0);
418 }
419
420 static struct page *osd_get_page(struct dt_object *dt, loff_t offset, int rw)
421 {
422         struct inode      *inode = osd_dt_obj(dt)->oo_inode;
423         struct osd_device *d = osd_obj2dev(osd_dt_obj(dt));
424         struct page       *page;
425
426         LASSERT(inode);
427
428         page = find_or_create_page(inode->i_mapping, offset >> PAGE_SHIFT,
429                                    GFP_NOFS | __GFP_HIGHMEM);
430         if (unlikely(page == NULL))
431                 lprocfs_counter_add(d->od_stats, LPROC_OSD_NO_PAGE, 1);
432
433         return page;
434 }
435
436 /*
437  * there are following "locks":
438  * journal_start
439  * i_mutex
440  * page lock
441  *
442  * osd write path:
443  *  - lock page(s)
444  *  - journal_start
445  *  - truncate_sem
446  *
447  * ext4 vmtruncate:
448  *  - lock pages, unlock
449  *  - journal_start
450  *  - lock partial page
451  *  - i_data_sem
452  *
453  */
454
455 /**
456  * Unlock and release pages loaded by osd_bufs_get()
457  *
458  * Unlock \a npages pages from \a lnb and drop the refcount on them.
459  *
460  * \param env           thread execution environment
461  * \param dt            dt object undergoing IO (OSD object + methods)
462  * \param lnb           array of pages undergoing IO
463  * \param npages        number of pages in \a lnb
464  *
465  * \retval 0            always
466  */
467 static int osd_bufs_put(const struct lu_env *env, struct dt_object *dt,
468                         struct niobuf_local *lnb, int npages)
469 {
470         int i;
471
472         for (i = 0; i < npages; i++) {
473                 if (lnb[i].lnb_page == NULL)
474                         continue;
475                 LASSERT(PageLocked(lnb[i].lnb_page));
476                 unlock_page(lnb[i].lnb_page);
477                 put_page(lnb[i].lnb_page);
478                 lu_object_put(env, &dt->do_lu);
479                 lnb[i].lnb_page = NULL;
480         }
481
482         RETURN(0);
483 }
484
485 /**
486  * Load and lock pages undergoing IO
487  *
488  * Pages as described in the \a lnb array are fetched (from disk or cache)
489  * and locked for IO by the caller.
490  *
491  * DLM locking protects us from write and truncate competing for same region,
492  * but partial-page truncate can leave dirty pages in the cache for ldiskfs.
493  * It's possible the writeout on a such a page is in progress when we access
494  * it. It's also possible that during this writeout we put new (partial) data
495  * into the page, but won't be able to proceed in filter_commitrw_write().
496  * Therefore, just wait for writeout completion as it should be rare enough.
497  *
498  * \param env           thread execution environment
499  * \param dt            dt object undergoing IO (OSD object + methods)
500  * \param pos           byte offset of IO start
501  * \param len           number of bytes of IO
502  * \param lnb           array of extents undergoing IO
503  * \param rw            read or write operation?
504  * \param capa          capabilities
505  *
506  * \retval pages        (zero or more) loaded successfully
507  * \retval -ENOMEM      on memory/page allocation error
508  */
509 static int osd_bufs_get(const struct lu_env *env, struct dt_object *dt,
510                         loff_t pos, ssize_t len, struct niobuf_local *lnb,
511                         int rw)
512 {
513         struct osd_object   *obj    = osd_dt_obj(dt);
514         int npages, i, rc = 0;
515
516         LASSERT(obj->oo_inode);
517
518         osd_map_remote_to_local(pos, len, &npages, lnb);
519
520         for (i = 0; i < npages; i++, lnb++) {
521                 lnb->lnb_page = osd_get_page(dt, lnb->lnb_file_offset, rw);
522                 if (lnb->lnb_page == NULL)
523                         GOTO(cleanup, rc = -ENOMEM);
524
525                 wait_on_page_writeback(lnb->lnb_page);
526                 BUG_ON(PageWriteback(lnb->lnb_page));
527
528                 lu_object_get(&dt->do_lu);
529         }
530
531         RETURN(i);
532
533 cleanup:
534         if (i > 0)
535                 osd_bufs_put(env, dt, lnb - i, i);
536         return rc;
537 }
538
539 #ifndef HAVE_LDISKFS_MAP_BLOCKS
540
541 #ifdef HAVE_EXT_PBLOCK /* Name changed to ext4_ext_pblock for kernel 2.6.35 */
542 #define ldiskfs_ext_pblock(ex) ext_pblock((ex))
543 #endif
544
545 struct bpointers {
546         sector_t *blocks;
547         unsigned long start;
548         int num;
549         int init_num;
550         int create;
551 };
552
553 static long ldiskfs_ext_find_goal(struct inode *inode,
554                                   struct ldiskfs_ext_path *path,
555                                   unsigned long block, int *aflags)
556 {
557         struct ldiskfs_inode_info *ei = LDISKFS_I(inode);
558         unsigned long bg_start;
559         unsigned long colour;
560         int depth;
561
562         if (path) {
563                 struct ldiskfs_extent *ex;
564                 depth = path->p_depth;
565
566                 /* try to predict block placement */
567                 if ((ex = path[depth].p_ext))
568                         return ldiskfs_ext_pblock(ex) +
569                                 (block - le32_to_cpu(ex->ee_block));
570
571                 /* it looks index is empty
572                  * try to find starting from index itself */
573                 if (path[depth].p_bh)
574                         return path[depth].p_bh->b_blocknr;
575         }
576
577         /* OK. use inode's group */
578         bg_start = (ei->i_block_group * LDISKFS_BLOCKS_PER_GROUP(inode->i_sb)) +
579                 le32_to_cpu(LDISKFS_SB(inode->i_sb)->s_es->s_first_data_block);
580         colour = (current->pid % 16) *
581                 (LDISKFS_BLOCKS_PER_GROUP(inode->i_sb) / 16);
582         return bg_start + colour + block;
583 }
584
585 static unsigned long new_blocks(handle_t *handle, struct inode *inode,
586                                 struct ldiskfs_ext_path *path,
587                                 unsigned long block, unsigned long *count,
588                                 int *err)
589 {
590         struct ldiskfs_allocation_request ar;
591         unsigned long pblock;
592         int aflags;
593
594         /* find neighbour allocated blocks */
595         ar.lleft = block;
596         *err = ldiskfs_ext_search_left(inode, path, &ar.lleft, &ar.pleft);
597         if (*err)
598                 return 0;
599         ar.lright = block;
600         *err = ldiskfs_ext_search_right(inode, path, &ar.lright, &ar.pright);
601         if (*err)
602                 return 0;
603
604         /* allocate new block */
605         ar.goal = ldiskfs_ext_find_goal(inode, path, block, &aflags);
606         ar.inode = inode;
607         ar.logical = block;
608         ar.len = *count;
609         ar.flags = LDISKFS_MB_HINT_DATA;
610         pblock = ldiskfs_mb_new_blocks(handle, &ar, err);
611         *count = ar.len;
612         return pblock;
613 }
614
615 static int ldiskfs_ext_new_extent_cb(struct inode *inode,
616                                      struct ldiskfs_ext_path *path,
617                                      struct ldiskfs_ext_cache *cex,
618 #ifdef HAVE_EXT_PREPARE_CB_EXTENT
619                                      struct ldiskfs_extent *ex,
620 #endif
621                                      void *cbdata)
622 {
623         struct bpointers *bp = cbdata;
624         struct ldiskfs_extent nex;
625         unsigned long pblock = 0;
626         unsigned long tgen;
627         int err, i;
628         unsigned long count;
629         handle_t *handle;
630
631 #ifdef LDISKFS_EXT_CACHE_EXTENT /* until kernel 2.6.37 */
632         if (cex->ec_type == LDISKFS_EXT_CACHE_EXTENT) {
633 #else
634         if ((cex->ec_len != 0) && (cex->ec_start != 0)) {
635 #endif
636                 err = EXT_CONTINUE;
637                 goto map;
638         }
639
640         if (bp->create == 0) {
641                 i = 0;
642                 if (cex->ec_block < bp->start)
643                         i = bp->start - cex->ec_block;
644                 if (i >= cex->ec_len)
645                         CERROR("nothing to do?! i = %d, e_num = %u\n",
646                                         i, cex->ec_len);
647                 for (; i < cex->ec_len && bp->num; i++) {
648                         *(bp->blocks) = 0;
649                         bp->blocks++;
650                         bp->num--;
651                         bp->start++;
652                 }
653
654                 return EXT_CONTINUE;
655         }
656
657         tgen = LDISKFS_I(inode)->i_ext_generation;
658         count = ldiskfs_ext_calc_credits_for_insert(inode, path);
659
660         handle = osd_journal_start(inode, LDISKFS_HT_MISC,
661                                    count + LDISKFS_ALLOC_NEEDED + 1);
662         if (IS_ERR(handle)) {
663                 return PTR_ERR(handle);
664         }
665
666         if (tgen != LDISKFS_I(inode)->i_ext_generation) {
667                 /* the tree has changed. so path can be invalid at moment */
668                 ldiskfs_journal_stop(handle);
669                 return EXT_REPEAT;
670         }
671
672         /* In 2.6.32 kernel, ldiskfs_ext_walk_space()'s callback func is not
673          * protected by i_data_sem as whole. so we patch it to store
674          * generation to path and now verify the tree hasn't changed */
675         down_write((&LDISKFS_I(inode)->i_data_sem));
676
677         /* validate extent, make sure the extent tree does not changed */
678         if (LDISKFS_I(inode)->i_ext_generation != path[0].p_generation) {
679                 /* cex is invalid, try again */
680                 up_write(&LDISKFS_I(inode)->i_data_sem);
681                 ldiskfs_journal_stop(handle);
682                 return EXT_REPEAT;
683         }
684
685         count = cex->ec_len;
686         pblock = new_blocks(handle, inode, path, cex->ec_block, &count, &err);
687         if (!pblock)
688                 goto out;
689         BUG_ON(count > cex->ec_len);
690
691         /* insert new extent */
692         nex.ee_block = cpu_to_le32(cex->ec_block);
693         ldiskfs_ext_store_pblock(&nex, pblock);
694         nex.ee_len = cpu_to_le16(count);
695         err = ldiskfs_ext_insert_extent(handle, inode, path, &nex, 0);
696         if (err) {
697                 /* free data blocks we just allocated */
698                 /* not a good idea to call discard here directly,
699                  * but otherwise we'd need to call it every free() */
700                 ldiskfs_discard_preallocations(inode);
701 #ifdef HAVE_EXT_FREE_BLOCK_WITH_BUFFER_HEAD /* Introduced in 2.6.32-rc7 */
702                 ldiskfs_free_blocks(handle, inode, NULL,
703                                     ldiskfs_ext_pblock(&nex),
704                                     le16_to_cpu(nex.ee_len), 0);
705 #else
706                 ldiskfs_free_blocks(handle, inode, ldiskfs_ext_pblock(&nex),
707                                     le16_to_cpu(nex.ee_len), 0);
708 #endif
709                 goto out;
710         }
711
712         /*
713          * Putting len of the actual extent we just inserted,
714          * we are asking ldiskfs_ext_walk_space() to continue
715          * scaning after that block
716          */
717         cex->ec_len = le16_to_cpu(nex.ee_len);
718         cex->ec_start = ldiskfs_ext_pblock(&nex);
719         BUG_ON(le16_to_cpu(nex.ee_len) == 0);
720         BUG_ON(le32_to_cpu(nex.ee_block) != cex->ec_block);
721
722 out:
723         up_write((&LDISKFS_I(inode)->i_data_sem));
724         ldiskfs_journal_stop(handle);
725 map:
726         if (err >= 0) {
727                 /* map blocks */
728                 if (bp->num == 0) {
729                         CERROR("hmm. why do we find this extent?\n");
730                         CERROR("initial space: %lu:%u\n",
731                                 bp->start, bp->init_num);
732 #ifdef LDISKFS_EXT_CACHE_EXTENT /* until kernel 2.6.37 */
733                         CERROR("current extent: %u/%u/%llu %d\n",
734                                 cex->ec_block, cex->ec_len,
735                                 (unsigned long long)cex->ec_start,
736                                 cex->ec_type);
737 #else
738                         CERROR("current extent: %u/%u/%llu\n",
739                                 cex->ec_block, cex->ec_len,
740                                 (unsigned long long)cex->ec_start);
741 #endif
742                 }
743                 i = 0;
744                 if (cex->ec_block < bp->start)
745                         i = bp->start - cex->ec_block;
746                 if (i >= cex->ec_len)
747                         CERROR("nothing to do?! i = %d, e_num = %u\n",
748                                         i, cex->ec_len);
749                 for (; i < cex->ec_len && bp->num; i++) {
750                         *(bp->blocks) = cex->ec_start + i;
751                         if (pblock != 0) {
752                                 /* unmap any possible underlying metadata from
753                                  * the block device mapping.  bug 6998. */
754                                 unmap_underlying_metadata(inode->i_sb->s_bdev,
755                                                           *(bp->blocks));
756                         }
757                         bp->blocks++;
758                         bp->num--;
759                         bp->start++;
760                 }
761         }
762         return err;
763 }
764
765 static int osd_ldiskfs_map_nblocks(struct inode *inode, unsigned long index,
766                                    int clen, sector_t *blocks, int create)
767 {
768         int blocks_per_page = PAGE_SIZE >> inode->i_blkbits;
769         struct bpointers bp;
770         int err;
771
772         if (index + clen >= inode->i_sb->s_maxbytes >> PAGE_SHIFT)
773                 return -EFBIG;
774
775         bp.blocks = blocks;
776         bp.start = index * blocks_per_page;
777         bp.init_num = bp.num = clen * blocks_per_page;
778         bp.create = create;
779
780         CDEBUG(D_OTHER, "blocks %lu-%lu requested for inode %u\n",
781                bp.start, bp.start + bp.num - 1, (unsigned)inode->i_ino);
782
783         err = ldiskfs_ext_walk_space(inode, bp.start, bp.num,
784                                      ldiskfs_ext_new_extent_cb, &bp);
785         ldiskfs_ext_invalidate_cache(inode);
786
787         return err;
788 }
789
790 static int osd_ldiskfs_map_bm_inode_pages(struct inode *inode,
791                                           struct page **page, int pages,
792                                           sector_t *blocks, int create)
793 {
794         int blocks_per_page = PAGE_SIZE >> inode->i_blkbits;
795         pgoff_t bitmap_max_page_index;
796         sector_t *b;
797         int rc = 0, i;
798
799         bitmap_max_page_index = LDISKFS_SB(inode->i_sb)->s_bitmap_maxbytes >>
800                                 PAGE_SHIFT;
801         for (i = 0, b = blocks; i < pages; i++, page++) {
802                 if ((*page)->index + 1 >= bitmap_max_page_index) {
803                         rc = -EFBIG;
804                         break;
805                 }
806                 rc = ldiskfs_map_inode_page(inode, *page, b, create);
807                 if (rc) {
808                         CERROR("ino %lu, blk %llu create %d: rc %d\n",
809                                inode->i_ino,
810                                (unsigned long long)*b, create, rc);
811                         break;
812                 }
813                 b += blocks_per_page;
814         }
815         return rc;
816 }
817
818 static int osd_ldiskfs_map_ext_inode_pages(struct inode *inode,
819                                            struct page **page,
820                                            int pages, sector_t *blocks,
821                                            int create)
822 {
823         int rc = 0, i = 0, clen = 0;
824         struct page *fp = NULL;
825
826         CDEBUG(D_OTHER, "inode %lu: map %d pages from %lu\n",
827                 inode->i_ino, pages, (*page)->index);
828
829         /* pages are sorted already. so, we just have to find
830          * contig. space and process them properly */
831         while (i < pages) {
832                 if (fp == NULL) {
833                         /* start new extent */
834                         fp = *page++;
835                         clen = 1;
836                         i++;
837                         continue;
838                 } else if (fp->index + clen == (*page)->index) {
839                         /* continue the extent */
840                         page++;
841                         clen++;
842                         i++;
843                         continue;
844                 }
845
846                 /* process found extent */
847                 rc = osd_ldiskfs_map_nblocks(inode, fp->index, clen,
848                                              blocks, create);
849                 if (rc)
850                         GOTO(cleanup, rc);
851
852                 /* look for next extent */
853                 fp = NULL;
854                 blocks += clen * (PAGE_SIZE >> inode->i_blkbits);
855         }
856
857         if (fp)
858                 rc = osd_ldiskfs_map_nblocks(inode, fp->index, clen,
859                                              blocks, create);
860
861 cleanup:
862         return rc;
863 }
864
865 static int osd_ldiskfs_map_inode_pages(struct inode *inode, struct page **page,
866                                        int pages, sector_t *blocks,
867                                        int create)
868 {
869         int rc;
870
871         if (LDISKFS_I(inode)->i_flags & LDISKFS_EXTENTS_FL) {
872                 rc = osd_ldiskfs_map_ext_inode_pages(inode, page, pages,
873                                                      blocks, create);
874                 return rc;
875         }
876         rc = osd_ldiskfs_map_bm_inode_pages(inode, page, pages, blocks, create);
877
878         return rc;
879 }
880 #else
881 static int osd_ldiskfs_map_inode_pages(struct inode *inode, struct page **page,
882                                        int pages, sector_t *blocks,
883                                        int create)
884 {
885         int blocks_per_page = PAGE_SIZE >> inode->i_blkbits;
886         int rc = 0, i = 0;
887         struct page *fp = NULL;
888         int clen = 0;
889         pgoff_t max_page_index;
890         handle_t *handle = NULL;
891
892         max_page_index = inode->i_sb->s_maxbytes >> PAGE_SHIFT;
893
894         CDEBUG(D_OTHER, "inode %lu: map %d pages from %lu\n",
895                 inode->i_ino, pages, (*page)->index);
896
897         if (create) {
898                 create = LDISKFS_GET_BLOCKS_CREATE;
899                 handle = ldiskfs_journal_current_handle();
900                 LASSERT(handle != NULL);
901                 rc = osd_attach_jinode(inode);
902                 if (rc)
903                         return rc;
904         }
905         /* pages are sorted already. so, we just have to find
906          * contig. space and process them properly */
907         while (i < pages) {
908                 long blen, total = 0;
909                 struct ldiskfs_map_blocks map = { 0 };
910
911                 if (fp == NULL) { /* start new extent */
912                         fp = *page++;
913                         clen = 1;
914                         if (++i != pages)
915                                 continue;
916                 } else if (fp->index + clen == (*page)->index) {
917                         /* continue the extent */
918                         page++;
919                         clen++;
920                         if (++i != pages)
921                                 continue;
922                 }
923                 if (fp->index + clen >= max_page_index)
924                         GOTO(cleanup, rc = -EFBIG);
925                 /* process found extent */
926                 map.m_lblk = fp->index * blocks_per_page;
927                 map.m_len = blen = clen * blocks_per_page;
928 cont_map:
929                 rc = ldiskfs_map_blocks(handle, inode, &map, create);
930                 if (rc >= 0) {
931                         int c = 0;
932                         for (; total < blen && c < map.m_len; c++, total++) {
933                                 if (rc == 0) {
934                                         *(blocks + total) = 0;
935                                         total++;
936                                         break;
937                                 } else {
938                                         *(blocks + total) = map.m_pblk + c;
939                                         /* unmap any possible underlying
940                                          * metadata from the block device
941                                          * mapping.  bug 6998. */
942                                         if ((map.m_flags & LDISKFS_MAP_NEW) &&
943                                             create)
944                                                 unmap_underlying_metadata(
945                                                         inode->i_sb->s_bdev,
946                                                         map.m_pblk + c);
947                                 }
948                         }
949                         rc = 0;
950                 }
951                 if (rc == 0 && total < blen) {
952                         map.m_lblk = fp->index * blocks_per_page + total;
953                         map.m_len = blen - total;
954                         goto cont_map;
955                 }
956                 if (rc != 0)
957                         GOTO(cleanup, rc);
958
959                 /* look for next extent */
960                 fp = NULL;
961                 blocks += blocks_per_page * clen;
962         }
963 cleanup:
964         return rc;
965 }
966 #endif /* HAVE_LDISKFS_MAP_BLOCKS */
967
968 static int osd_write_prep(const struct lu_env *env, struct dt_object *dt,
969                           struct niobuf_local *lnb, int npages)
970 {
971         struct osd_thread_info *oti   = osd_oti_get(env);
972         struct osd_iobuf       *iobuf = &oti->oti_iobuf;
973         struct inode           *inode = osd_dt_obj(dt)->oo_inode;
974         struct osd_device      *osd   = osd_obj2dev(osd_dt_obj(dt));
975         ktime_t start;
976         ktime_t end;
977         s64 timediff;
978         ssize_t                 isize;
979         __s64                   maxidx;
980         int                     rc = 0;
981         int                     i;
982         int                     cache = 0;
983
984         LASSERT(inode);
985
986         rc = osd_init_iobuf(osd, iobuf, 0, npages);
987         if (unlikely(rc != 0))
988                 RETURN(rc);
989
990         isize = i_size_read(inode);
991         maxidx = ((isize + PAGE_SIZE - 1) >> PAGE_SHIFT) - 1;
992
993         if (osd->od_writethrough_cache)
994                 cache = 1;
995         if (isize > osd->od_readcache_max_filesize)
996                 cache = 0;
997
998         start = ktime_get();
999         for (i = 0; i < npages; i++) {
1000
1001                 if (cache == 0)
1002                         generic_error_remove_page(inode->i_mapping,
1003                                                   lnb[i].lnb_page);
1004
1005                 /*
1006                  * till commit the content of the page is undefined
1007                  * we'll set it uptodate once bulk is done. otherwise
1008                  * subsequent reads can access non-stable data
1009                  */
1010                 ClearPageUptodate(lnb[i].lnb_page);
1011
1012                 if (lnb[i].lnb_len == PAGE_SIZE)
1013                         continue;
1014
1015                 if (maxidx >= lnb[i].lnb_page->index) {
1016                         osd_iobuf_add_page(iobuf, lnb[i].lnb_page);
1017                 } else {
1018                         long off;
1019                         char *p = kmap(lnb[i].lnb_page);
1020
1021                         off = lnb[i].lnb_page_offset;
1022                         if (off)
1023                                 memset(p, 0, off);
1024                         off = (lnb[i].lnb_page_offset + lnb[i].lnb_len) &
1025                               ~PAGE_MASK;
1026                         if (off)
1027                                 memset(p + off, 0, PAGE_SIZE - off);
1028                         kunmap(lnb[i].lnb_page);
1029                 }
1030         }
1031         end = ktime_get();
1032         timediff = ktime_us_delta(end, start);
1033         lprocfs_counter_add(osd->od_stats, LPROC_OSD_GET_PAGE, timediff);
1034
1035         if (iobuf->dr_npages) {
1036                 rc = osd_ldiskfs_map_inode_pages(inode, iobuf->dr_pages,
1037                                                  iobuf->dr_npages,
1038                                                  iobuf->dr_blocks, 0);
1039                 if (likely(rc == 0)) {
1040                         rc = osd_do_bio(osd, inode, iobuf);
1041                         /* do IO stats for preparation reads */
1042                         osd_fini_iobuf(osd, iobuf);
1043                 }
1044         }
1045         RETURN(rc);
1046 }
1047
1048 struct osd_fextent {
1049         sector_t        start;
1050         sector_t        end;
1051         unsigned int    mapped:1;
1052 };
1053
1054 static int osd_is_mapped(struct dt_object *dt, __u64 offset,
1055                          struct osd_fextent *cached_extent)
1056 {
1057         struct inode *inode = osd_dt_obj(dt)->oo_inode;
1058         sector_t block = offset >> inode->i_blkbits;
1059         sector_t start;
1060         struct fiemap_extent_info fei = { 0 };
1061         struct fiemap_extent fe = { 0 };
1062         mm_segment_t saved_fs;
1063         int rc;
1064
1065         if (block >= cached_extent->start && block < cached_extent->end)
1066                 return cached_extent->mapped;
1067
1068         if (i_size_read(inode) == 0)
1069                 return 0;
1070
1071         /* Beyond EOF, must not be mapped */
1072         if (((i_size_read(inode) - 1) >> inode->i_blkbits) < block)
1073                 return 0;
1074
1075         fei.fi_extents_max = 1;
1076         fei.fi_extents_start = &fe;
1077
1078         saved_fs = get_fs();
1079         set_fs(get_ds());
1080         rc = inode->i_op->fiemap(inode, &fei, offset, FIEMAP_MAX_OFFSET-offset);
1081         set_fs(saved_fs);
1082         if (rc != 0)
1083                 return 0;
1084
1085         start = fe.fe_logical >> inode->i_blkbits;
1086
1087         if (start > block) {
1088                 cached_extent->start = block;
1089                 cached_extent->end = start;
1090                 cached_extent->mapped = 0;
1091         } else {
1092                 cached_extent->start = start;
1093                 cached_extent->end = (fe.fe_logical + fe.fe_length) >>
1094                                       inode->i_blkbits;
1095                 cached_extent->mapped = 1;
1096         }
1097
1098         return cached_extent->mapped;
1099 }
1100
1101 static int osd_declare_write_commit(const struct lu_env *env,
1102                                     struct dt_object *dt,
1103                                     struct niobuf_local *lnb, int npages,
1104                                     struct thandle *handle)
1105 {
1106         const struct osd_device *osd = osd_obj2dev(osd_dt_obj(dt));
1107         struct inode            *inode = osd_dt_obj(dt)->oo_inode;
1108         struct osd_thandle      *oh;
1109         int                      extents = 1;
1110         int                      depth;
1111         int                      i;
1112         int                      newblocks;
1113         int                      rc = 0;
1114         int                      flags = 0;
1115         int                      credits = 0;
1116         bool                     ignore_quota = false;
1117         long long                quota_space = 0;
1118         struct osd_fextent       extent = { 0 };
1119         ENTRY;
1120
1121         LASSERT(handle != NULL);
1122         oh = container_of0(handle, struct osd_thandle, ot_super);
1123         LASSERT(oh->ot_handle == NULL);
1124
1125         newblocks = npages;
1126
1127         /* calculate number of extents (probably better to pass nb) */
1128         for (i = 0; i < npages; i++) {
1129                 if (i && lnb[i].lnb_file_offset !=
1130                     lnb[i - 1].lnb_file_offset + lnb[i - 1].lnb_len)
1131                         extents++;
1132
1133                 if (!osd_is_mapped(dt, lnb[i].lnb_file_offset, &extent))
1134                         quota_space += PAGE_SIZE;
1135
1136                 /* ignore quota for the whole request if any page is from
1137                  * client cache or written by root.
1138                  *
1139                  * XXX once we drop the 1.8 client support, the checking
1140                  * for whether page is from cache can be simplified as:
1141                  * !(lnb[i].flags & OBD_BRW_SYNC)
1142                  *
1143                  * XXX we could handle this on per-lnb basis as done by
1144                  * grant. */
1145                 if ((lnb[i].lnb_flags & OBD_BRW_NOQUOTA) ||
1146                     (lnb[i].lnb_flags & (OBD_BRW_FROM_GRANT | OBD_BRW_SYNC)) ==
1147                     OBD_BRW_FROM_GRANT)
1148                         ignore_quota = true;
1149         }
1150
1151         /*
1152          * each extent can go into new leaf causing a split
1153          * 5 is max tree depth: inode + 4 index blocks
1154          * with blockmaps, depth is 3 at most
1155          */
1156         if (LDISKFS_I(inode)->i_flags & LDISKFS_EXTENTS_FL) {
1157                 /*
1158                  * many concurrent threads may grow tree by the time
1159                  * our transaction starts. so, consider 2 is a min depth
1160                  */
1161                 depth = ext_depth(inode);
1162                 depth = max(depth, 1) + 1;
1163                 newblocks += depth;
1164                 credits++; /* inode */
1165                 credits += depth * 2 * extents;
1166         } else {
1167                 depth = 3;
1168                 newblocks += depth;
1169                 credits++; /* inode */
1170                 credits += depth * extents;
1171         }
1172
1173         /* quota space for metadata blocks */
1174         quota_space += depth * extents * LDISKFS_BLOCK_SIZE(osd_sb(osd));
1175
1176         /* quota space should be reported in 1K blocks */
1177         quota_space = toqb(quota_space);
1178
1179         /* each new block can go in different group (bitmap + gd) */
1180
1181         /* we can't dirty more bitmap blocks than exist */
1182         if (newblocks > LDISKFS_SB(osd_sb(osd))->s_groups_count)
1183                 credits += LDISKFS_SB(osd_sb(osd))->s_groups_count;
1184         else
1185                 credits += newblocks;
1186
1187         /* we can't dirty more gd blocks than exist */
1188         if (newblocks > LDISKFS_SB(osd_sb(osd))->s_gdb_count)
1189                 credits += LDISKFS_SB(osd_sb(osd))->s_gdb_count;
1190         else
1191                 credits += newblocks;
1192
1193         osd_trans_declare_op(env, oh, OSD_OT_WRITE, credits);
1194
1195         /* make sure the over quota flags were not set */
1196         lnb[0].lnb_flags &= ~(OBD_BRW_OVER_USRQUOTA | OBD_BRW_OVER_GRPQUOTA);
1197
1198         rc = osd_declare_inode_qid(env, i_uid_read(inode), i_gid_read(inode),
1199                                    quota_space, oh, osd_dt_obj(dt), true,
1200                                    &flags, ignore_quota);
1201
1202         /* we need only to store the overquota flags in the first lnb for
1203          * now, once we support multiple objects BRW, this code needs be
1204          * revised. */
1205         if (flags & QUOTA_FL_OVER_USRQUOTA)
1206                 lnb[0].lnb_flags |= OBD_BRW_OVER_USRQUOTA;
1207         if (flags & QUOTA_FL_OVER_GRPQUOTA)
1208                 lnb[0].lnb_flags |= OBD_BRW_OVER_GRPQUOTA;
1209
1210         RETURN(rc);
1211 }
1212
1213 /* Check if a block is allocated or not */
1214 static int osd_write_commit(const struct lu_env *env, struct dt_object *dt,
1215                             struct niobuf_local *lnb, int npages,
1216                             struct thandle *thandle)
1217 {
1218         struct osd_thread_info *oti = osd_oti_get(env);
1219         struct osd_iobuf *iobuf = &oti->oti_iobuf;
1220         struct inode *inode = osd_dt_obj(dt)->oo_inode;
1221         struct osd_device  *osd = osd_obj2dev(osd_dt_obj(dt));
1222         loff_t isize;
1223         int rc = 0, i;
1224         struct osd_fextent extent = { 0 };
1225
1226         LASSERT(inode);
1227
1228         rc = osd_init_iobuf(osd, iobuf, 1, npages);
1229         if (unlikely(rc != 0))
1230                 RETURN(rc);
1231
1232         isize = i_size_read(inode);
1233         ll_vfs_dq_init(inode);
1234
1235         for (i = 0; i < npages; i++) {
1236                 if (lnb[i].lnb_rc == -ENOSPC &&
1237                     osd_is_mapped(dt, lnb[i].lnb_file_offset, &extent)) {
1238                         /* Allow the write to proceed if overwriting an
1239                          * existing block */
1240                         lnb[i].lnb_rc = 0;
1241                 }
1242
1243                 if (lnb[i].lnb_rc) { /* ENOSPC, network RPC error, etc. */
1244                         CDEBUG(D_INODE, "Skipping [%d] == %d\n", i,
1245                                lnb[i].lnb_rc);
1246                         LASSERT(lnb[i].lnb_page);
1247                         generic_error_remove_page(inode->i_mapping,
1248                                                   lnb[i].lnb_page);
1249                         continue;
1250                 }
1251
1252                 LASSERT(PageLocked(lnb[i].lnb_page));
1253                 LASSERT(!PageWriteback(lnb[i].lnb_page));
1254
1255                 if (lnb[i].lnb_file_offset + lnb[i].lnb_len > isize)
1256                         isize = lnb[i].lnb_file_offset + lnb[i].lnb_len;
1257
1258                 /*
1259                  * Since write and truncate are serialized by oo_sem, even
1260                  * partial-page truncate should not leave dirty pages in the
1261                  * page cache.
1262                  */
1263                 LASSERT(!PageDirty(lnb[i].lnb_page));
1264
1265                 SetPageUptodate(lnb[i].lnb_page);
1266
1267                 osd_iobuf_add_page(iobuf, lnb[i].lnb_page);
1268         }
1269
1270         osd_trans_exec_op(env, thandle, OSD_OT_WRITE);
1271
1272         if (OBD_FAIL_CHECK(OBD_FAIL_OST_MAPBLK_ENOSPC)) {
1273                 rc = -ENOSPC;
1274         } else if (iobuf->dr_npages > 0) {
1275                 rc = osd_ldiskfs_map_inode_pages(inode, iobuf->dr_pages,
1276                                                  iobuf->dr_npages,
1277                                                  iobuf->dr_blocks, 1);
1278         } else {
1279                 /* no pages to write, no transno is needed */
1280                 thandle->th_local = 1;
1281         }
1282
1283         if (likely(rc == 0)) {
1284                 spin_lock(&inode->i_lock);
1285                 if (isize > i_size_read(inode)) {
1286                         i_size_write(inode, isize);
1287                         LDISKFS_I(inode)->i_disksize = isize;
1288                         spin_unlock(&inode->i_lock);
1289                         ll_dirty_inode(inode, I_DIRTY_DATASYNC);
1290                 } else {
1291                         spin_unlock(&inode->i_lock);
1292                 }
1293
1294                 rc = osd_do_bio(osd, inode, iobuf);
1295                 /* we don't do stats here as in read path because
1296                  * write is async: we'll do this in osd_put_bufs() */
1297         } else {
1298                 osd_fini_iobuf(osd, iobuf);
1299         }
1300
1301         osd_trans_exec_check(env, thandle, OSD_OT_WRITE);
1302
1303         if (unlikely(rc != 0)) {
1304                 /* if write fails, we should drop pages from the cache */
1305                 for (i = 0; i < npages; i++) {
1306                         if (lnb[i].lnb_page == NULL)
1307                                 continue;
1308                         LASSERT(PageLocked(lnb[i].lnb_page));
1309                         generic_error_remove_page(inode->i_mapping,
1310                                                   lnb[i].lnb_page);
1311                 }
1312         }
1313
1314         RETURN(rc);
1315 }
1316
1317 static int osd_read_prep(const struct lu_env *env, struct dt_object *dt,
1318                          struct niobuf_local *lnb, int npages)
1319 {
1320         struct osd_thread_info *oti = osd_oti_get(env);
1321         struct osd_iobuf *iobuf = &oti->oti_iobuf;
1322         struct inode *inode = osd_dt_obj(dt)->oo_inode;
1323         struct osd_device *osd = osd_obj2dev(osd_dt_obj(dt));
1324         int rc = 0, i, cache = 0, cache_hits = 0, cache_misses = 0;
1325         ktime_t start, end;
1326         s64 timediff;
1327         loff_t isize;
1328
1329         LASSERT(inode);
1330
1331         rc = osd_init_iobuf(osd, iobuf, 0, npages);
1332         if (unlikely(rc != 0))
1333                 RETURN(rc);
1334
1335         isize = i_size_read(inode);
1336
1337         if (osd->od_read_cache)
1338                 cache = 1;
1339         if (isize > osd->od_readcache_max_filesize)
1340                 cache = 0;
1341
1342         start = ktime_get();
1343         for (i = 0; i < npages; i++) {
1344
1345                 if (isize <= lnb[i].lnb_file_offset)
1346                         /* If there's no more data, abort early.
1347                          * lnb->lnb_rc == 0, so it's easy to detect later. */
1348                         break;
1349
1350                 if (isize < lnb[i].lnb_file_offset + lnb[i].lnb_len)
1351                         lnb[i].lnb_rc = isize - lnb[i].lnb_file_offset;
1352                 else
1353                         lnb[i].lnb_rc = lnb[i].lnb_len;
1354
1355                 if (PageUptodate(lnb[i].lnb_page)) {
1356                         cache_hits++;
1357                 } else {
1358                         cache_misses++;
1359                         osd_iobuf_add_page(iobuf, lnb[i].lnb_page);
1360                 }
1361
1362                 if (cache == 0)
1363                         generic_error_remove_page(inode->i_mapping,
1364                                                   lnb[i].lnb_page);
1365         }
1366         end = ktime_get();
1367         timediff = ktime_us_delta(end, start);
1368         lprocfs_counter_add(osd->od_stats, LPROC_OSD_GET_PAGE, timediff);
1369
1370         if (cache_hits != 0)
1371                 lprocfs_counter_add(osd->od_stats, LPROC_OSD_CACHE_HIT,
1372                                     cache_hits);
1373         if (cache_misses != 0)
1374                 lprocfs_counter_add(osd->od_stats, LPROC_OSD_CACHE_MISS,
1375                                     cache_misses);
1376         if (cache_hits + cache_misses != 0)
1377                 lprocfs_counter_add(osd->od_stats, LPROC_OSD_CACHE_ACCESS,
1378                                     cache_hits + cache_misses);
1379
1380         if (iobuf->dr_npages) {
1381                 rc = osd_ldiskfs_map_inode_pages(inode, iobuf->dr_pages,
1382                                                  iobuf->dr_npages,
1383                                                  iobuf->dr_blocks, 0);
1384                 rc = osd_do_bio(osd, inode, iobuf);
1385
1386                 /* IO stats will be done in osd_bufs_put() */
1387         }
1388
1389         RETURN(rc);
1390 }
1391
1392 /*
1393  * XXX: Another layering violation for now.
1394  *
1395  * We don't want to use ->f_op->read methods, because generic file write
1396  *
1397  *         - serializes on ->i_sem, and
1398  *
1399  *         - does a lot of extra work like balance_dirty_pages(),
1400  *
1401  * which doesn't work for globally shared files like /last_rcvd.
1402  */
1403 static int osd_ldiskfs_readlink(struct inode *inode, char *buffer, int buflen)
1404 {
1405         struct ldiskfs_inode_info *ei = LDISKFS_I(inode);
1406
1407         memcpy(buffer, (char *)ei->i_data, buflen);
1408
1409         return  buflen;
1410 }
1411
1412 int osd_ldiskfs_read(struct inode *inode, void *buf, int size, loff_t *offs)
1413 {
1414         struct buffer_head *bh;
1415         unsigned long block;
1416         int osize;
1417         int blocksize;
1418         int csize;
1419         int boffs;
1420
1421         /* prevent reading after eof */
1422         spin_lock(&inode->i_lock);
1423         if (i_size_read(inode) < *offs + size) {
1424                 loff_t diff = i_size_read(inode) - *offs;
1425                 spin_unlock(&inode->i_lock);
1426                 if (diff < 0) {
1427                         CDEBUG(D_EXT2, "size %llu is too short to read @%llu\n",
1428                                i_size_read(inode), *offs);
1429                         return -EBADR;
1430                 } else if (diff == 0) {
1431                         return 0;
1432                 } else {
1433                         size = diff;
1434                 }
1435         } else {
1436                 spin_unlock(&inode->i_lock);
1437         }
1438
1439         blocksize = 1 << inode->i_blkbits;
1440         osize = size;
1441         while (size > 0) {
1442                 block = *offs >> inode->i_blkbits;
1443                 boffs = *offs & (blocksize - 1);
1444                 csize = min(blocksize - boffs, size);
1445                 bh = __ldiskfs_bread(NULL, inode, block, 0);
1446                 if (IS_ERR(bh)) {
1447                         CERROR("%s: can't read %u@%llu on ino %lu: rc = %ld\n",
1448                                LDISKFS_SB(inode->i_sb)->s_es->s_volume_name,
1449                                csize, *offs, inode->i_ino,
1450                                PTR_ERR(bh));
1451                         return PTR_ERR(bh);
1452                 }
1453
1454                 if (bh != NULL) {
1455                         memcpy(buf, bh->b_data + boffs, csize);
1456                         brelse(bh);
1457                 } else {
1458                         memset(buf, 0, csize);
1459                 }
1460
1461                 *offs += csize;
1462                 buf += csize;
1463                 size -= csize;
1464         }
1465         return osize;
1466 }
1467
1468 static ssize_t osd_read(const struct lu_env *env, struct dt_object *dt,
1469                         struct lu_buf *buf, loff_t *pos)
1470 {
1471         struct inode *inode = osd_dt_obj(dt)->oo_inode;
1472         int           rc;
1473
1474         /* Read small symlink from inode body as we need to maintain correct
1475          * on-disk symlinks for ldiskfs.
1476          */
1477         if (S_ISLNK(dt->do_lu.lo_header->loh_attr) &&
1478             (buf->lb_len < sizeof(LDISKFS_I(inode)->i_data)))
1479                 rc = osd_ldiskfs_readlink(inode, buf->lb_buf, buf->lb_len);
1480         else
1481                 rc = osd_ldiskfs_read(inode, buf->lb_buf, buf->lb_len, pos);
1482
1483         return rc;
1484 }
1485
1486 static inline int osd_extents_enabled(struct super_block *sb,
1487                                       struct inode *inode)
1488 {
1489         if (inode != NULL) {
1490                 if (LDISKFS_I(inode)->i_flags & LDISKFS_EXTENTS_FL)
1491                         return 1;
1492         } else if (LDISKFS_HAS_INCOMPAT_FEATURE(sb,
1493                                 LDISKFS_FEATURE_INCOMPAT_EXTENTS)) {
1494                 return 1;
1495         }
1496         return 0;
1497 }
1498
1499 int osd_calc_bkmap_credits(struct super_block *sb, struct inode *inode,
1500                            const loff_t size, const loff_t pos,
1501                            const int blocks)
1502 {
1503         int credits, bits, bs, i;
1504
1505         bits = sb->s_blocksize_bits;
1506         bs = 1 << bits;
1507
1508         /* legacy blockmap: 3 levels * 3 (bitmap,gd,itself)
1509          * we do not expect blockmaps on the large files,
1510          * so let's shrink it to 2 levels (4GB files) */
1511
1512         /* this is default reservation: 2 levels */
1513         credits = (blocks + 2) * 3;
1514
1515         /* actual offset is unknown, hard to optimize */
1516         if (pos == -1)
1517                 return credits;
1518
1519         /* now check for few specific cases to optimize */
1520         if (pos + size <= LDISKFS_NDIR_BLOCKS * bs) {
1521                 /* no indirects */
1522                 credits = blocks;
1523                 /* allocate if not allocated */
1524                 if (inode == NULL) {
1525                         credits += blocks * 2;
1526                         return credits;
1527                 }
1528                 for (i = (pos >> bits); i < (pos >> bits) + blocks; i++) {
1529                         LASSERT(i < LDISKFS_NDIR_BLOCKS);
1530                         if (LDISKFS_I(inode)->i_data[i] == 0)
1531                                 credits += 2;
1532                 }
1533         } else if (pos + size <= (LDISKFS_NDIR_BLOCKS + 1024) * bs) {
1534                 /* single indirect */
1535                 credits = blocks * 3;
1536                 if (inode == NULL ||
1537                     LDISKFS_I(inode)->i_data[LDISKFS_IND_BLOCK] == 0)
1538                         credits += 3;
1539                 else
1540                         /* The indirect block may be modified. */
1541                         credits += 1;
1542         }
1543
1544         return credits;
1545 }
1546
1547 static ssize_t osd_declare_write(const struct lu_env *env, struct dt_object *dt,
1548                                  const struct lu_buf *buf, loff_t _pos,
1549                                  struct thandle *handle)
1550 {
1551         struct osd_object  *obj  = osd_dt_obj(dt);
1552         struct inode       *inode = obj->oo_inode;
1553         struct super_block *sb = osd_sb(osd_obj2dev(obj));
1554         struct osd_thandle *oh;
1555         int                 rc = 0, est = 0, credits, blocks, allocated = 0;
1556         int                 bits, bs;
1557         int                 depth, size;
1558         loff_t              pos;
1559         ENTRY;
1560
1561         LASSERT(buf != NULL);
1562         LASSERT(handle != NULL);
1563
1564         oh = container_of0(handle, struct osd_thandle, ot_super);
1565         LASSERT(oh->ot_handle == NULL);
1566
1567         size = buf->lb_len;
1568         bits = sb->s_blocksize_bits;
1569         bs = 1 << bits;
1570
1571         if (_pos == -1) {
1572                 /* if this is an append, then we
1573                  * should expect cross-block record */
1574                 pos = 0;
1575         } else {
1576                 pos = _pos;
1577         }
1578
1579         /* blocks to modify */
1580         blocks = ((pos + size + bs - 1) >> bits) - (pos >> bits);
1581         LASSERT(blocks > 0);
1582
1583         if (inode != NULL && _pos != -1) {
1584                 /* object size in blocks */
1585                 est = (i_size_read(inode) + bs - 1) >> bits;
1586                 allocated = inode->i_blocks >> (bits - 9);
1587                 if (pos + size <= i_size_read(inode) && est <= allocated) {
1588                         /* looks like an overwrite, no need to modify tree */
1589                         credits = blocks;
1590                         /* no need to modify i_size */
1591                         goto out;
1592                 }
1593         }
1594
1595         if (osd_extents_enabled(sb, inode)) {
1596                 /*
1597                  * many concurrent threads may grow tree by the time
1598                  * our transaction starts. so, consider 2 is a min depth
1599                  * for every level we may need to allocate a new block
1600                  * and take some entries from the old one. so, 3 blocks
1601                  * to allocate (bitmap, gd, itself) + old block - 4 per
1602                  * level.
1603                  */
1604                 depth = inode != NULL ? ext_depth(inode) : 0;
1605                 depth = max(depth, 1) + 1;
1606                 credits = depth;
1607                 /* if not append, then split may need to modify
1608                  * existing blocks moving entries into the new ones */
1609                 if (_pos == -1)
1610                         credits += depth;
1611                 /* blocks to store data: bitmap,gd,itself */
1612                 credits += blocks * 3;
1613         } else {
1614                 credits = osd_calc_bkmap_credits(sb, inode, size, _pos, blocks);
1615         }
1616         /* if inode is created as part of the transaction,
1617          * then it's counted already by the creation method */
1618         if (inode != NULL)
1619                 credits++;
1620
1621 out:
1622
1623         osd_trans_declare_op(env, oh, OSD_OT_WRITE, credits);
1624
1625         /* dt_declare_write() is usually called for system objects, such
1626          * as llog or last_rcvd files. We needn't enforce quota on those
1627          * objects, so always set the lqi_space as 0. */
1628         if (inode != NULL)
1629                 rc = osd_declare_inode_qid(env, i_uid_read(inode),
1630                                            i_gid_read(inode), 0, oh, obj, true,
1631                                            NULL, false);
1632         RETURN(rc);
1633 }
1634
1635 static int osd_ldiskfs_writelink(struct inode *inode, char *buffer, int buflen)
1636 {
1637         /* LU-2634: clear the extent format for fast symlink */
1638         ldiskfs_clear_inode_flag(inode, LDISKFS_INODE_EXTENTS);
1639
1640         memcpy((char *)&LDISKFS_I(inode)->i_data, (char *)buffer, buflen);
1641         spin_lock(&inode->i_lock);
1642         LDISKFS_I(inode)->i_disksize = buflen;
1643         i_size_write(inode, buflen);
1644         spin_unlock(&inode->i_lock);
1645         ll_dirty_inode(inode, I_DIRTY_DATASYNC);
1646
1647         return 0;
1648 }
1649
1650 int osd_ldiskfs_write_record(struct inode *inode, void *buf, int bufsize,
1651                              int write_NUL, loff_t *offs, handle_t *handle)
1652 {
1653         struct buffer_head *bh        = NULL;
1654         loff_t              offset    = *offs;
1655         loff_t              new_size  = i_size_read(inode);
1656         unsigned long       block;
1657         int                 blocksize = 1 << inode->i_blkbits;
1658         int                 err = 0;
1659         int                 size;
1660         int                 boffs;
1661         int                 dirty_inode = 0;
1662
1663         if (write_NUL) {
1664                 /*
1665                  * long symlink write does not count the NUL terminator in
1666                  * bufsize, we write it, and the inode's file size does not
1667                  * count the NUL terminator as well.
1668                  */
1669                 ((char *)buf)[bufsize] = '\0';
1670                 ++bufsize;
1671         }
1672         while (bufsize > 0) {
1673                 if (bh != NULL)
1674                         brelse(bh);
1675
1676                 block = offset >> inode->i_blkbits;
1677                 boffs = offset & (blocksize - 1);
1678                 size = min(blocksize - boffs, bufsize);
1679                 bh = __ldiskfs_bread(handle, inode, block, 1);
1680                 if (IS_ERR_OR_NULL(bh)) {
1681                         if (bh == NULL) {
1682                                 err = -EIO;
1683                         } else {
1684                                 err = PTR_ERR(bh);
1685                                 bh = NULL;
1686                         }
1687                         CERROR("%s: error reading offset %llu (block %lu): "
1688                                "rc = %d\n",
1689                                inode->i_sb->s_id, offset, block, err);
1690                         break;
1691                 }
1692
1693                 err = ldiskfs_journal_get_write_access(handle, bh);
1694                 if (err) {
1695                         CERROR("journal_get_write_access() returned error %d\n",
1696                                err);
1697                         break;
1698                 }
1699                 LASSERTF(boffs + size <= bh->b_size,
1700                          "boffs %d size %d bh->b_size %lu\n",
1701                          boffs, size, (unsigned long)bh->b_size);
1702                 memcpy(bh->b_data + boffs, buf, size);
1703                 err = ldiskfs_handle_dirty_metadata(handle, NULL, bh);
1704                 if (err)
1705                         break;
1706
1707                 if (offset + size > new_size)
1708                         new_size = offset + size;
1709                 offset += size;
1710                 bufsize -= size;
1711                 buf += size;
1712         }
1713         if (bh)
1714                 brelse(bh);
1715
1716         if (write_NUL)
1717                 --new_size;
1718         /* correct in-core and on-disk sizes */
1719         if (new_size > i_size_read(inode)) {
1720                 spin_lock(&inode->i_lock);
1721                 if (new_size > i_size_read(inode))
1722                         i_size_write(inode, new_size);
1723                 if (i_size_read(inode) > LDISKFS_I(inode)->i_disksize) {
1724                         LDISKFS_I(inode)->i_disksize = i_size_read(inode);
1725                         dirty_inode = 1;
1726                 }
1727                 spin_unlock(&inode->i_lock);
1728                 if (dirty_inode)
1729                         ll_dirty_inode(inode, I_DIRTY_DATASYNC);
1730         }
1731
1732         if (err == 0)
1733                 *offs = offset;
1734         return err;
1735 }
1736
1737 static ssize_t osd_write(const struct lu_env *env, struct dt_object *dt,
1738                          const struct lu_buf *buf, loff_t *pos,
1739                          struct thandle *handle, int ignore_quota)
1740 {
1741         struct inode            *inode = osd_dt_obj(dt)->oo_inode;
1742         struct osd_thandle      *oh;
1743         ssize_t                 result;
1744         int                     is_link;
1745
1746         LASSERT(dt_object_exists(dt));
1747
1748         LASSERT(handle != NULL);
1749         LASSERT(inode != NULL);
1750         ll_vfs_dq_init(inode);
1751
1752         /* XXX: don't check: one declared chunk can be used many times */
1753         /* osd_trans_exec_op(env, handle, OSD_OT_WRITE); */
1754
1755         oh = container_of(handle, struct osd_thandle, ot_super);
1756         LASSERT(oh->ot_handle->h_transaction != NULL);
1757         osd_trans_exec_op(env, handle, OSD_OT_WRITE);
1758
1759         /* Write small symlink to inode body as we need to maintain correct
1760          * on-disk symlinks for ldiskfs.
1761          * Note: the buf->lb_buf contains a NUL terminator while buf->lb_len
1762          * does not count it in.
1763          */
1764         is_link = S_ISLNK(dt->do_lu.lo_header->loh_attr);
1765         if (is_link && (buf->lb_len < sizeof(LDISKFS_I(inode)->i_data)))
1766                 result = osd_ldiskfs_writelink(inode, buf->lb_buf, buf->lb_len);
1767         else
1768                 result = osd_ldiskfs_write_record(inode, buf->lb_buf,
1769                                                   buf->lb_len, is_link, pos,
1770                                                   oh->ot_handle);
1771         if (result == 0)
1772                 result = buf->lb_len;
1773
1774         osd_trans_exec_check(env, handle, OSD_OT_WRITE);
1775
1776         return result;
1777 }
1778
1779 static int osd_declare_punch(const struct lu_env *env, struct dt_object *dt,
1780                              __u64 start, __u64 end, struct thandle *th)
1781 {
1782         struct osd_thandle *oh;
1783         struct inode       *inode;
1784         int                 rc;
1785         ENTRY;
1786
1787         LASSERT(th);
1788         oh = container_of(th, struct osd_thandle, ot_super);
1789
1790         /*
1791          * we don't need to reserve credits for whole truncate
1792          * it's not possible as truncate may need to free too many
1793          * blocks and that won't fit a single transaction. instead
1794          * we reserve credits to change i_size and put inode onto
1795          * orphan list. if needed truncate will extend or restart
1796          * transaction
1797          */
1798         osd_trans_declare_op(env, oh, OSD_OT_PUNCH,
1799                              osd_dto_credits_noquota[DTO_ATTR_SET_BASE] + 3);
1800
1801         inode = osd_dt_obj(dt)->oo_inode;
1802         LASSERT(inode);
1803
1804         rc = osd_declare_inode_qid(env, i_uid_read(inode), i_gid_read(inode),
1805                                    0, oh, osd_dt_obj(dt), true, NULL, false);
1806         RETURN(rc);
1807 }
1808
1809 static int osd_punch(const struct lu_env *env, struct dt_object *dt,
1810                      __u64 start, __u64 end, struct thandle *th)
1811 {
1812         struct osd_thandle *oh;
1813         struct osd_object  *obj = osd_dt_obj(dt);
1814         struct inode       *inode = obj->oo_inode;
1815         handle_t           *h;
1816         tid_t               tid;
1817         int                rc = 0, rc2 = 0;
1818         ENTRY;
1819
1820         LASSERT(end == OBD_OBJECT_EOF);
1821         LASSERT(dt_object_exists(dt));
1822         LASSERT(osd_invariant(obj));
1823         LASSERT(inode != NULL);
1824         ll_vfs_dq_init(inode);
1825
1826         LASSERT(th);
1827         oh = container_of(th, struct osd_thandle, ot_super);
1828         LASSERT(oh->ot_handle->h_transaction != NULL);
1829
1830         osd_trans_exec_op(env, th, OSD_OT_PUNCH);
1831
1832         tid = oh->ot_handle->h_transaction->t_tid;
1833
1834         spin_lock(&inode->i_lock);
1835         i_size_write(inode, start);
1836         spin_unlock(&inode->i_lock);
1837         ll_truncate_pagecache(inode, start);
1838 #ifdef HAVE_INODEOPS_TRUNCATE
1839         if (inode->i_op->truncate) {
1840                 inode->i_op->truncate(inode);
1841         } else
1842 #endif
1843                 ldiskfs_truncate(inode);
1844
1845         /*
1846          * For a partial-page truncate, flush the page to disk immediately to
1847          * avoid data corruption during direct disk write.  b=17397
1848          */
1849         if ((start & ~PAGE_MASK) != 0)
1850                 rc = filemap_fdatawrite_range(inode->i_mapping, start, start+1);
1851
1852         h = journal_current_handle();
1853         LASSERT(h != NULL);
1854         LASSERT(h == oh->ot_handle);
1855
1856         /* do not check credits with osd_trans_exec_check() as the truncate
1857          * can restart the transaction internally and we restart the
1858          * transaction in this case */
1859
1860         if (tid != h->h_transaction->t_tid) {
1861                 int credits = oh->ot_credits;
1862                 /*
1863                  * transaction has changed during truncate
1864                  * we need to restart the handle with our credits
1865                  */
1866                 if (h->h_buffer_credits < credits) {
1867                         if (ldiskfs_journal_extend(h, credits))
1868                                 rc2 = ldiskfs_journal_restart(h, credits);
1869                 }
1870         }
1871
1872         RETURN(rc == 0 ? rc2 : rc);
1873 }
1874
1875 static int fiemap_check_ranges(struct inode *inode,
1876                                u64 start, u64 len, u64 *new_len)
1877 {
1878         loff_t maxbytes;
1879
1880         *new_len = len;
1881
1882         if (len == 0)
1883                 return -EINVAL;
1884
1885         if (ldiskfs_test_inode_flag(inode, LDISKFS_INODE_EXTENTS))
1886                 maxbytes = inode->i_sb->s_maxbytes;
1887         else
1888                 maxbytes = LDISKFS_SB(inode->i_sb)->s_bitmap_maxbytes;
1889
1890         if (start > maxbytes)
1891                 return -EFBIG;
1892
1893         /*
1894          * Shrink request scope to what the fs can actually handle.
1895          */
1896         if (len > maxbytes || (maxbytes - len) < start)
1897                 *new_len = maxbytes - start;
1898
1899         return 0;
1900 }
1901
1902 /* So that the fiemap access checks can't overflow on 32 bit machines. */
1903 #define FIEMAP_MAX_EXTENTS     (UINT_MAX / sizeof(struct fiemap_extent))
1904
1905 static int osd_fiemap_get(const struct lu_env *env, struct dt_object *dt,
1906                           struct fiemap *fm)
1907 {
1908         struct fiemap_extent_info fieinfo = {0, };
1909         struct inode *inode = osd_dt_obj(dt)->oo_inode;
1910         u64 len;
1911         int rc;
1912
1913
1914         LASSERT(inode);
1915         if (inode->i_op->fiemap == NULL)
1916                 return -EOPNOTSUPP;
1917
1918         if (fm->fm_extent_count > FIEMAP_MAX_EXTENTS)
1919                 return -EINVAL;
1920
1921         rc = fiemap_check_ranges(inode, fm->fm_start, fm->fm_length, &len);
1922         if (rc)
1923                 return rc;
1924
1925         fieinfo.fi_flags = fm->fm_flags;
1926         fieinfo.fi_extents_max = fm->fm_extent_count;
1927         fieinfo.fi_extents_start = fm->fm_extents;
1928
1929         if (fieinfo.fi_flags & FIEMAP_FLAG_SYNC)
1930                 filemap_write_and_wait(inode->i_mapping);
1931
1932         rc = inode->i_op->fiemap(inode, &fieinfo, fm->fm_start, len);
1933         fm->fm_flags = fieinfo.fi_flags;
1934         fm->fm_mapped_extents = fieinfo.fi_extents_mapped;
1935
1936         return rc;
1937 }
1938
1939 static int osd_ladvise(const struct lu_env *env, struct dt_object *dt,
1940                        __u64 start, __u64 end, enum lu_ladvise_type advice)
1941 {
1942         int              rc = 0;
1943         struct inode    *inode = osd_dt_obj(dt)->oo_inode;
1944         ENTRY;
1945
1946         switch (advice) {
1947         case LU_LADVISE_DONTNEED:
1948                 if (end == 0)
1949                         break;
1950                 invalidate_mapping_pages(inode->i_mapping,
1951                                          start >> PAGE_CACHE_SHIFT,
1952                                          (end - 1) >> PAGE_CACHE_SHIFT);
1953                 break;
1954         default:
1955                 rc = -ENOTSUPP;
1956                 break;
1957         }
1958
1959         RETURN(rc);
1960 }
1961
1962 /*
1963  * in some cases we may need declare methods for objects being created
1964  * e.g., when we create symlink
1965  */
1966 const struct dt_body_operations osd_body_ops_new = {
1967         .dbo_declare_write = osd_declare_write,
1968 };
1969
1970 const struct dt_body_operations osd_body_ops = {
1971         .dbo_read                       = osd_read,
1972         .dbo_declare_write              = osd_declare_write,
1973         .dbo_write                      = osd_write,
1974         .dbo_bufs_get                   = osd_bufs_get,
1975         .dbo_bufs_put                   = osd_bufs_put,
1976         .dbo_write_prep                 = osd_write_prep,
1977         .dbo_declare_write_commit       = osd_declare_write_commit,
1978         .dbo_write_commit               = osd_write_commit,
1979         .dbo_read_prep                  = osd_read_prep,
1980         .dbo_declare_punch              = osd_declare_punch,
1981         .dbo_punch                      = osd_punch,
1982         .dbo_fiemap_get                 = osd_fiemap_get,
1983         .dbo_ladvise                    = osd_ladvise,
1984 };