Merge branch 'stable/for-jens-3.14' of git://git.kernel.org/pub/scm/linux/kernel...
[platform/adaptation/renesas_rcar/renesas_kernel.git] / fs / exofs / ore.c
1 /*
2  * Copyright (C) 2005, 2006
3  * Avishay Traeger (avishay@gmail.com)
4  * Copyright (C) 2008, 2009
5  * Boaz Harrosh <bharrosh@panasas.com>
6  *
7  * This file is part of exofs.
8  *
9  * exofs is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License as published by
11  * the Free Software Foundation.  Since it is based on ext2, and the only
12  * valid version of GPL for the Linux kernel is version 2, the only valid
13  * version of GPL for exofs is version 2.
14  *
15  * exofs is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18  * GNU General Public License for more details.
19  *
20  * You should have received a copy of the GNU General Public License
21  * along with exofs; if not, write to the Free Software
22  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
23  */
24
25 #include <linux/slab.h>
26 #include <linux/module.h>
27 #include <asm/div64.h>
28 #include <linux/lcm.h>
29
30 #include "ore_raid.h"
31
32 MODULE_AUTHOR("Boaz Harrosh <bharrosh@panasas.com>");
33 MODULE_DESCRIPTION("Objects Raid Engine ore.ko");
34 MODULE_LICENSE("GPL");
35
36 /* ore_verify_layout does a couple of things:
37  * 1. Given a minimum number of needed parameters fixes up the rest of the
38  *    members to be operatonals for the ore. The needed parameters are those
39  *    that are defined by the pnfs-objects layout STD.
40  * 2. Check to see if the current ore code actually supports these parameters
41  *    for example stripe_unit must be a multple of the system PAGE_SIZE,
42  *    and etc...
43  * 3. Cache some havily used calculations that will be needed by users.
44  */
45
46 enum { BIO_MAX_PAGES_KMALLOC =
47                 (PAGE_SIZE - sizeof(struct bio)) / sizeof(struct bio_vec),};
48
49 int ore_verify_layout(unsigned total_comps, struct ore_layout *layout)
50 {
51         u64 stripe_length;
52
53         switch (layout->raid_algorithm) {
54         case PNFS_OSD_RAID_0:
55                 layout->parity = 0;
56                 break;
57         case PNFS_OSD_RAID_5:
58                 layout->parity = 1;
59                 break;
60         case PNFS_OSD_RAID_PQ:
61         case PNFS_OSD_RAID_4:
62         default:
63                 ORE_ERR("Only RAID_0/5 for now\n");
64                 return -EINVAL;
65         }
66         if (0 != (layout->stripe_unit & ~PAGE_MASK)) {
67                 ORE_ERR("Stripe Unit(0x%llx)"
68                           " must be Multples of PAGE_SIZE(0x%lx)\n",
69                           _LLU(layout->stripe_unit), PAGE_SIZE);
70                 return -EINVAL;
71         }
72         if (layout->group_width) {
73                 if (!layout->group_depth) {
74                         ORE_ERR("group_depth == 0 && group_width != 0\n");
75                         return -EINVAL;
76                 }
77                 if (total_comps < (layout->group_width * layout->mirrors_p1)) {
78                         ORE_ERR("Data Map wrong, "
79                                 "numdevs=%d < group_width=%d * mirrors=%d\n",
80                                 total_comps, layout->group_width,
81                                 layout->mirrors_p1);
82                         return -EINVAL;
83                 }
84                 layout->group_count = total_comps / layout->mirrors_p1 /
85                                                 layout->group_width;
86         } else {
87                 if (layout->group_depth) {
88                         printk(KERN_NOTICE "Warning: group_depth ignored "
89                                 "group_width == 0 && group_depth == %lld\n",
90                                 _LLU(layout->group_depth));
91                 }
92                 layout->group_width = total_comps / layout->mirrors_p1;
93                 layout->group_depth = -1;
94                 layout->group_count = 1;
95         }
96
97         stripe_length = (u64)layout->group_width * layout->stripe_unit;
98         if (stripe_length >= (1ULL << 32)) {
99                 ORE_ERR("Stripe_length(0x%llx) >= 32bit is not supported\n",
100                         _LLU(stripe_length));
101                 return -EINVAL;
102         }
103
104         layout->max_io_length =
105                 (BIO_MAX_PAGES_KMALLOC * PAGE_SIZE - layout->stripe_unit) *
106                                         (layout->group_width - layout->parity);
107         if (layout->parity) {
108                 unsigned stripe_length =
109                                 (layout->group_width - layout->parity) *
110                                 layout->stripe_unit;
111
112                 layout->max_io_length /= stripe_length;
113                 layout->max_io_length *= stripe_length;
114         }
115         return 0;
116 }
117 EXPORT_SYMBOL(ore_verify_layout);
118
119 static u8 *_ios_cred(struct ore_io_state *ios, unsigned index)
120 {
121         return ios->oc->comps[index & ios->oc->single_comp].cred;
122 }
123
124 static struct osd_obj_id *_ios_obj(struct ore_io_state *ios, unsigned index)
125 {
126         return &ios->oc->comps[index & ios->oc->single_comp].obj;
127 }
128
129 static struct osd_dev *_ios_od(struct ore_io_state *ios, unsigned index)
130 {
131         ORE_DBGMSG2("oc->first_dev=%d oc->numdevs=%d i=%d oc->ods=%p\n",
132                     ios->oc->first_dev, ios->oc->numdevs, index,
133                     ios->oc->ods);
134
135         return ore_comp_dev(ios->oc, index);
136 }
137
138 int  _ore_get_io_state(struct ore_layout *layout,
139                         struct ore_components *oc, unsigned numdevs,
140                         unsigned sgs_per_dev, unsigned num_par_pages,
141                         struct ore_io_state **pios)
142 {
143         struct ore_io_state *ios;
144         struct page **pages;
145         struct osd_sg_entry *sgilist;
146         struct __alloc_all_io_state {
147                 struct ore_io_state ios;
148                 struct ore_per_dev_state per_dev[numdevs];
149                 union {
150                         struct osd_sg_entry sglist[sgs_per_dev * numdevs];
151                         struct page *pages[num_par_pages];
152                 };
153         } *_aios;
154
155         if (likely(sizeof(*_aios) <= PAGE_SIZE)) {
156                 _aios = kzalloc(sizeof(*_aios), GFP_KERNEL);
157                 if (unlikely(!_aios)) {
158                         ORE_DBGMSG("Failed kzalloc bytes=%zd\n",
159                                    sizeof(*_aios));
160                         *pios = NULL;
161                         return -ENOMEM;
162                 }
163                 pages = num_par_pages ? _aios->pages : NULL;
164                 sgilist = sgs_per_dev ? _aios->sglist : NULL;
165                 ios = &_aios->ios;
166         } else {
167                 struct __alloc_small_io_state {
168                         struct ore_io_state ios;
169                         struct ore_per_dev_state per_dev[numdevs];
170                 } *_aio_small;
171                 union __extra_part {
172                         struct osd_sg_entry sglist[sgs_per_dev * numdevs];
173                         struct page *pages[num_par_pages];
174                 } *extra_part;
175
176                 _aio_small = kzalloc(sizeof(*_aio_small), GFP_KERNEL);
177                 if (unlikely(!_aio_small)) {
178                         ORE_DBGMSG("Failed alloc first part bytes=%zd\n",
179                                    sizeof(*_aio_small));
180                         *pios = NULL;
181                         return -ENOMEM;
182                 }
183                 extra_part = kzalloc(sizeof(*extra_part), GFP_KERNEL);
184                 if (unlikely(!extra_part)) {
185                         ORE_DBGMSG("Failed alloc second part bytes=%zd\n",
186                                    sizeof(*extra_part));
187                         kfree(_aio_small);
188                         *pios = NULL;
189                         return -ENOMEM;
190                 }
191
192                 pages = num_par_pages ? extra_part->pages : NULL;
193                 sgilist = sgs_per_dev ? extra_part->sglist : NULL;
194                 /* In this case the per_dev[0].sgilist holds the pointer to
195                  * be freed
196                  */
197                 ios = &_aio_small->ios;
198                 ios->extra_part_alloc = true;
199         }
200
201         if (pages) {
202                 ios->parity_pages = pages;
203                 ios->max_par_pages = num_par_pages;
204         }
205         if (sgilist) {
206                 unsigned d;
207
208                 for (d = 0; d < numdevs; ++d) {
209                         ios->per_dev[d].sglist = sgilist;
210                         sgilist += sgs_per_dev;
211                 }
212                 ios->sgs_per_dev = sgs_per_dev;
213         }
214
215         ios->layout = layout;
216         ios->oc = oc;
217         *pios = ios;
218         return 0;
219 }
220
221 /* Allocate an io_state for only a single group of devices
222  *
223  * If a user needs to call ore_read/write() this version must be used becase it
224  * allocates extra stuff for striping and raid.
225  * The ore might decide to only IO less then @length bytes do to alignmets
226  * and constrains as follows:
227  * - The IO cannot cross group boundary.
228  * - In raid5/6 The end of the IO must align at end of a stripe eg.
229  *   (@offset + @length) % strip_size == 0. Or the complete range is within a
230  *   single stripe.
231  * - Memory condition only permitted a shorter IO. (A user can use @length=~0
232  *   And check the returned ios->length for max_io_size.)
233  *
234  * The caller must check returned ios->length (and/or ios->nr_pages) and
235  * re-issue these pages that fall outside of ios->length
236  */
237 int  ore_get_rw_state(struct ore_layout *layout, struct ore_components *oc,
238                       bool is_reading, u64 offset, u64 length,
239                       struct ore_io_state **pios)
240 {
241         struct ore_io_state *ios;
242         unsigned numdevs = layout->group_width * layout->mirrors_p1;
243         unsigned sgs_per_dev = 0, max_par_pages = 0;
244         int ret;
245
246         if (layout->parity && length) {
247                 unsigned data_devs = layout->group_width - layout->parity;
248                 unsigned stripe_size = layout->stripe_unit * data_devs;
249                 unsigned pages_in_unit = layout->stripe_unit / PAGE_SIZE;
250                 u32 remainder;
251                 u64 num_stripes;
252                 u64 num_raid_units;
253
254                 num_stripes = div_u64_rem(length, stripe_size, &remainder);
255                 if (remainder)
256                         ++num_stripes;
257
258                 num_raid_units =  num_stripes * layout->parity;
259
260                 if (is_reading) {
261                         /* For reads add per_dev sglist array */
262                         /* TODO: Raid 6 we need twice more. Actually:
263                         *         num_stripes / LCMdP(W,P);
264                         *         if (W%P != 0) num_stripes *= parity;
265                         */
266
267                         /* first/last seg is split */
268                         num_raid_units += layout->group_width;
269                         sgs_per_dev = div_u64(num_raid_units, data_devs) + 2;
270                 } else {
271                         /* For Writes add parity pages array. */
272                         max_par_pages = num_raid_units * pages_in_unit *
273                                                 sizeof(struct page *);
274                 }
275         }
276
277         ret = _ore_get_io_state(layout, oc, numdevs, sgs_per_dev, max_par_pages,
278                                 pios);
279         if (unlikely(ret))
280                 return ret;
281
282         ios = *pios;
283         ios->reading = is_reading;
284         ios->offset = offset;
285
286         if (length) {
287                 ore_calc_stripe_info(layout, offset, length, &ios->si);
288                 ios->length = ios->si.length;
289                 ios->nr_pages = ((ios->offset & (PAGE_SIZE - 1)) +
290                                  ios->length + PAGE_SIZE - 1) / PAGE_SIZE;
291                 if (layout->parity)
292                         _ore_post_alloc_raid_stuff(ios);
293         }
294
295         return 0;
296 }
297 EXPORT_SYMBOL(ore_get_rw_state);
298
299 /* Allocate an io_state for all the devices in the comps array
300  *
301  * This version of io_state allocation is used mostly by create/remove
302  * and trunc where we currently need all the devices. The only wastful
303  * bit is the read/write_attributes with no IO. Those sites should
304  * be converted to use ore_get_rw_state() with length=0
305  */
306 int  ore_get_io_state(struct ore_layout *layout, struct ore_components *oc,
307                       struct ore_io_state **pios)
308 {
309         return _ore_get_io_state(layout, oc, oc->numdevs, 0, 0, pios);
310 }
311 EXPORT_SYMBOL(ore_get_io_state);
312
313 void ore_put_io_state(struct ore_io_state *ios)
314 {
315         if (ios) {
316                 unsigned i;
317
318                 for (i = 0; i < ios->numdevs; i++) {
319                         struct ore_per_dev_state *per_dev = &ios->per_dev[i];
320
321                         if (per_dev->or)
322                                 osd_end_request(per_dev->or);
323                         if (per_dev->bio)
324                                 bio_put(per_dev->bio);
325                 }
326
327                 _ore_free_raid_stuff(ios);
328                 kfree(ios);
329         }
330 }
331 EXPORT_SYMBOL(ore_put_io_state);
332
333 static void _sync_done(struct ore_io_state *ios, void *p)
334 {
335         struct completion *waiting = p;
336
337         complete(waiting);
338 }
339
340 static void _last_io(struct kref *kref)
341 {
342         struct ore_io_state *ios = container_of(
343                                         kref, struct ore_io_state, kref);
344
345         ios->done(ios, ios->private);
346 }
347
348 static void _done_io(struct osd_request *or, void *p)
349 {
350         struct ore_io_state *ios = p;
351
352         kref_put(&ios->kref, _last_io);
353 }
354
355 int ore_io_execute(struct ore_io_state *ios)
356 {
357         DECLARE_COMPLETION_ONSTACK(wait);
358         bool sync = (ios->done == NULL);
359         int i, ret;
360
361         if (sync) {
362                 ios->done = _sync_done;
363                 ios->private = &wait;
364         }
365
366         for (i = 0; i < ios->numdevs; i++) {
367                 struct osd_request *or = ios->per_dev[i].or;
368                 if (unlikely(!or))
369                         continue;
370
371                 ret = osd_finalize_request(or, 0, _ios_cred(ios, i), NULL);
372                 if (unlikely(ret)) {
373                         ORE_DBGMSG("Failed to osd_finalize_request() => %d\n",
374                                      ret);
375                         return ret;
376                 }
377         }
378
379         kref_init(&ios->kref);
380
381         for (i = 0; i < ios->numdevs; i++) {
382                 struct osd_request *or = ios->per_dev[i].or;
383                 if (unlikely(!or))
384                         continue;
385
386                 kref_get(&ios->kref);
387                 osd_execute_request_async(or, _done_io, ios);
388         }
389
390         kref_put(&ios->kref, _last_io);
391         ret = 0;
392
393         if (sync) {
394                 wait_for_completion(&wait);
395                 ret = ore_check_io(ios, NULL);
396         }
397         return ret;
398 }
399
400 static void _clear_bio(struct bio *bio)
401 {
402         struct bio_vec *bv;
403         unsigned i;
404
405         bio_for_each_segment_all(bv, bio, i) {
406                 unsigned this_count = bv->bv_len;
407
408                 if (likely(PAGE_SIZE == this_count))
409                         clear_highpage(bv->bv_page);
410                 else
411                         zero_user(bv->bv_page, bv->bv_offset, this_count);
412         }
413 }
414
415 int ore_check_io(struct ore_io_state *ios, ore_on_dev_error on_dev_error)
416 {
417         enum osd_err_priority acumulated_osd_err = 0;
418         int acumulated_lin_err = 0;
419         int i;
420
421         for (i = 0; i < ios->numdevs; i++) {
422                 struct osd_sense_info osi;
423                 struct ore_per_dev_state *per_dev = &ios->per_dev[i];
424                 struct osd_request *or = per_dev->or;
425                 int ret;
426
427                 if (unlikely(!or))
428                         continue;
429
430                 ret = osd_req_decode_sense(or, &osi);
431                 if (likely(!ret))
432                         continue;
433
434                 if ((OSD_ERR_PRI_CLEAR_PAGES == osi.osd_err_pri) &&
435                     per_dev->bio) {
436                         /* start read offset passed endof file.
437                          * Note: if we do not have bio it means read-attributes
438                          * In this case we should return error to caller.
439                          */
440                         _clear_bio(per_dev->bio);
441                         ORE_DBGMSG("start read offset passed end of file "
442                                 "offset=0x%llx, length=0x%llx\n",
443                                 _LLU(per_dev->offset),
444                                 _LLU(per_dev->length));
445
446                         continue; /* we recovered */
447                 }
448
449                 if (on_dev_error) {
450                         u64 residual = ios->reading ?
451                                         or->in.residual : or->out.residual;
452                         u64 offset = (ios->offset + ios->length) - residual;
453                         unsigned dev = per_dev->dev - ios->oc->first_dev;
454                         struct ore_dev *od = ios->oc->ods[dev];
455
456                         on_dev_error(ios, od, dev, osi.osd_err_pri,
457                                      offset, residual);
458                 }
459                 if (osi.osd_err_pri >= acumulated_osd_err) {
460                         acumulated_osd_err = osi.osd_err_pri;
461                         acumulated_lin_err = ret;
462                 }
463         }
464
465         return acumulated_lin_err;
466 }
467 EXPORT_SYMBOL(ore_check_io);
468
469 /*
470  * L - logical offset into the file
471  *
472  * D - number of Data devices
473  *      D = group_width - parity
474  *
475  * U - The number of bytes in a stripe within a group
476  *      U =  stripe_unit * D
477  *
478  * T - The number of bytes striped within a group of component objects
479  *     (before advancing to the next group)
480  *      T = U * group_depth
481  *
482  * S - The number of bytes striped across all component objects
483  *     before the pattern repeats
484  *      S = T * group_count
485  *
486  * M - The "major" (i.e., across all components) cycle number
487  *      M = L / S
488  *
489  * G - Counts the groups from the beginning of the major cycle
490  *      G = (L - (M * S)) / T   [or (L % S) / T]
491  *
492  * H - The byte offset within the group
493  *      H = (L - (M * S)) % T   [or (L % S) % T]
494  *
495  * N - The "minor" (i.e., across the group) stripe number
496  *      N = H / U
497  *
498  * C - The component index coresponding to L
499  *
500  *      C = (H - (N * U)) / stripe_unit + G * D
501  *      [or (L % U) / stripe_unit + G * D]
502  *
503  * O - The component offset coresponding to L
504  *      O = L % stripe_unit + N * stripe_unit + M * group_depth * stripe_unit
505  *
506  * LCMdP â€“ Parity cycle: Lowest Common Multiple of group_width, parity
507  *          divide by parity
508  *      LCMdP = lcm(group_width, parity) / parity
509  *
510  * R - The parity Rotation stripe
511  *     (Note parity cycle always starts at a group's boundary)
512  *      R = N % LCMdP
513  *
514  * I = the first parity device index
515  *      I = (group_width + group_width - R*parity - parity) % group_width
516  *
517  * Craid - The component index Rotated
518  *      Craid = (group_width + C - R*parity) % group_width
519  *      (We add the group_width to avoid negative numbers modulo math)
520  */
521 void ore_calc_stripe_info(struct ore_layout *layout, u64 file_offset,
522                           u64 length, struct ore_striping_info *si)
523 {
524         u32     stripe_unit = layout->stripe_unit;
525         u32     group_width = layout->group_width;
526         u64     group_depth = layout->group_depth;
527         u32     parity      = layout->parity;
528
529         u32     D = group_width - parity;
530         u32     U = D * stripe_unit;
531         u64     T = U * group_depth;
532         u64     S = T * layout->group_count;
533         u64     M = div64_u64(file_offset, S);
534
535         /*
536         G = (L - (M * S)) / T
537         H = (L - (M * S)) % T
538         */
539         u64     LmodS = file_offset - M * S;
540         u32     G = div64_u64(LmodS, T);
541         u64     H = LmodS - G * T;
542
543         u32     N = div_u64(H, U);
544         u32     Nlast;
545
546         /* "H - (N * U)" is just "H % U" so it's bound to u32 */
547         u32     C = (u32)(H - (N * U)) / stripe_unit + G * group_width;
548
549         div_u64_rem(file_offset, stripe_unit, &si->unit_off);
550
551         si->obj_offset = si->unit_off + (N * stripe_unit) +
552                                   (M * group_depth * stripe_unit);
553
554         if (parity) {
555                 u32 LCMdP = lcm(group_width, parity) / parity;
556                 /* R     = N % LCMdP; */
557                 u32 RxP   = (N % LCMdP) * parity;
558                 u32 first_dev = C - C % group_width;
559
560                 si->par_dev = (group_width + group_width - parity - RxP) %
561                               group_width + first_dev;
562                 si->dev = (group_width + C - RxP) % group_width + first_dev;
563                 si->bytes_in_stripe = U;
564                 si->first_stripe_start = M * S + G * T + N * U;
565         } else {
566                 /* Make the math correct see _prepare_one_group */
567                 si->par_dev = group_width;
568                 si->dev = C;
569         }
570
571         si->dev *= layout->mirrors_p1;
572         si->par_dev *= layout->mirrors_p1;
573         si->offset = file_offset;
574         si->length = T - H;
575         if (si->length > length)
576                 si->length = length;
577
578         Nlast = div_u64(H + si->length + U - 1, U);
579         si->maxdevUnits = Nlast - N;
580
581         si->M = M;
582 }
583 EXPORT_SYMBOL(ore_calc_stripe_info);
584
585 int _ore_add_stripe_unit(struct ore_io_state *ios,  unsigned *cur_pg,
586                          unsigned pgbase, struct page **pages,
587                          struct ore_per_dev_state *per_dev, int cur_len)
588 {
589         unsigned pg = *cur_pg;
590         struct request_queue *q =
591                         osd_request_queue(_ios_od(ios, per_dev->dev));
592         unsigned len = cur_len;
593         int ret;
594
595         if (per_dev->bio == NULL) {
596                 unsigned bio_size;
597
598                 if (!ios->reading) {
599                         bio_size = ios->si.maxdevUnits;
600                 } else {
601                         bio_size = (ios->si.maxdevUnits + 1) *
602                              (ios->layout->group_width - ios->layout->parity) /
603                              ios->layout->group_width;
604                 }
605                 bio_size *= (ios->layout->stripe_unit / PAGE_SIZE);
606
607                 per_dev->bio = bio_kmalloc(GFP_KERNEL, bio_size);
608                 if (unlikely(!per_dev->bio)) {
609                         ORE_DBGMSG("Failed to allocate BIO size=%u\n",
610                                      bio_size);
611                         ret = -ENOMEM;
612                         goto out;
613                 }
614         }
615
616         while (cur_len > 0) {
617                 unsigned pglen = min_t(unsigned, PAGE_SIZE - pgbase, cur_len);
618                 unsigned added_len;
619
620                 cur_len -= pglen;
621
622                 added_len = bio_add_pc_page(q, per_dev->bio, pages[pg],
623                                             pglen, pgbase);
624                 if (unlikely(pglen != added_len)) {
625                         /* If bi_vcnt == bi_max then this is a SW BUG */
626                         ORE_DBGMSG("Failed bio_add_pc_page bi_vcnt=0x%x "
627                                    "bi_max=0x%x BIO_MAX=0x%x cur_len=0x%x\n",
628                                    per_dev->bio->bi_vcnt,
629                                    per_dev->bio->bi_max_vecs,
630                                    BIO_MAX_PAGES_KMALLOC, cur_len);
631                         ret = -ENOMEM;
632                         goto out;
633                 }
634                 _add_stripe_page(ios->sp2d, &ios->si, pages[pg]);
635
636                 pgbase = 0;
637                 ++pg;
638         }
639         BUG_ON(cur_len);
640
641         per_dev->length += len;
642         *cur_pg = pg;
643         ret = 0;
644 out:    /* we fail the complete unit on an error eg don't advance
645          * per_dev->length and cur_pg. This means that we might have a bigger
646          * bio than the CDB requested length (per_dev->length). That's fine
647          * only the oposite is fatal.
648          */
649         return ret;
650 }
651
652 static int _prepare_for_striping(struct ore_io_state *ios)
653 {
654         struct ore_striping_info *si = &ios->si;
655         unsigned stripe_unit = ios->layout->stripe_unit;
656         unsigned mirrors_p1 = ios->layout->mirrors_p1;
657         unsigned group_width = ios->layout->group_width;
658         unsigned devs_in_group = group_width * mirrors_p1;
659         unsigned dev = si->dev;
660         unsigned first_dev = dev - (dev % devs_in_group);
661         unsigned dev_order;
662         unsigned cur_pg = ios->pages_consumed;
663         u64 length = ios->length;
664         int ret = 0;
665
666         if (!ios->pages) {
667                 ios->numdevs = ios->layout->mirrors_p1;
668                 return 0;
669         }
670
671         BUG_ON(length > si->length);
672
673         dev_order = _dev_order(devs_in_group, mirrors_p1, si->par_dev, dev);
674         si->cur_comp = dev_order;
675         si->cur_pg = si->unit_off / PAGE_SIZE;
676
677         while (length) {
678                 unsigned comp = dev - first_dev;
679                 struct ore_per_dev_state *per_dev = &ios->per_dev[comp];
680                 unsigned cur_len, page_off = 0;
681
682                 if (!per_dev->length) {
683                         per_dev->dev = dev;
684                         if (dev == si->dev) {
685                                 WARN_ON(dev == si->par_dev);
686                                 per_dev->offset = si->obj_offset;
687                                 cur_len = stripe_unit - si->unit_off;
688                                 page_off = si->unit_off & ~PAGE_MASK;
689                                 BUG_ON(page_off && (page_off != ios->pgbase));
690                         } else {
691                                 if (si->cur_comp > dev_order)
692                                         per_dev->offset =
693                                                 si->obj_offset - si->unit_off;
694                                 else /* si->cur_comp < dev_order */
695                                         per_dev->offset =
696                                                 si->obj_offset + stripe_unit -
697                                                                    si->unit_off;
698                                 cur_len = stripe_unit;
699                         }
700                 } else {
701                         cur_len = stripe_unit;
702                 }
703                 if (cur_len >= length)
704                         cur_len = length;
705
706                 ret = _ore_add_stripe_unit(ios, &cur_pg, page_off, ios->pages,
707                                            per_dev, cur_len);
708                 if (unlikely(ret))
709                         goto out;
710
711                 dev += mirrors_p1;
712                 dev = (dev % devs_in_group) + first_dev;
713
714                 length -= cur_len;
715
716                 si->cur_comp = (si->cur_comp + 1) % group_width;
717                 if (unlikely((dev == si->par_dev) || (!length && ios->sp2d))) {
718                         if (!length && ios->sp2d) {
719                                 /* If we are writing and this is the very last
720                                  * stripe. then operate on parity dev.
721                                  */
722                                 dev = si->par_dev;
723                         }
724                         if (ios->sp2d)
725                                 /* In writes cur_len just means if it's the
726                                  * last one. See _ore_add_parity_unit.
727                                  */
728                                 cur_len = length;
729                         per_dev = &ios->per_dev[dev - first_dev];
730                         if (!per_dev->length) {
731                                 /* Only/always the parity unit of the first
732                                  * stripe will be empty. So this is a chance to
733                                  * initialize the per_dev info.
734                                  */
735                                 per_dev->dev = dev;
736                                 per_dev->offset = si->obj_offset - si->unit_off;
737                         }
738
739                         ret = _ore_add_parity_unit(ios, si, per_dev, cur_len);
740                         if (unlikely(ret))
741                                         goto out;
742
743                         /* Rotate next par_dev backwards with wraping */
744                         si->par_dev = (devs_in_group + si->par_dev -
745                                        ios->layout->parity * mirrors_p1) %
746                                       devs_in_group + first_dev;
747                         /* Next stripe, start fresh */
748                         si->cur_comp = 0;
749                         si->cur_pg = 0;
750                 }
751         }
752 out:
753         ios->numdevs = devs_in_group;
754         ios->pages_consumed = cur_pg;
755         return ret;
756 }
757
758 int ore_create(struct ore_io_state *ios)
759 {
760         int i, ret;
761
762         for (i = 0; i < ios->oc->numdevs; i++) {
763                 struct osd_request *or;
764
765                 or = osd_start_request(_ios_od(ios, i), GFP_KERNEL);
766                 if (unlikely(!or)) {
767                         ORE_ERR("%s: osd_start_request failed\n", __func__);
768                         ret = -ENOMEM;
769                         goto out;
770                 }
771                 ios->per_dev[i].or = or;
772                 ios->numdevs++;
773
774                 osd_req_create_object(or, _ios_obj(ios, i));
775         }
776         ret = ore_io_execute(ios);
777
778 out:
779         return ret;
780 }
781 EXPORT_SYMBOL(ore_create);
782
783 int ore_remove(struct ore_io_state *ios)
784 {
785         int i, ret;
786
787         for (i = 0; i < ios->oc->numdevs; i++) {
788                 struct osd_request *or;
789
790                 or = osd_start_request(_ios_od(ios, i), GFP_KERNEL);
791                 if (unlikely(!or)) {
792                         ORE_ERR("%s: osd_start_request failed\n", __func__);
793                         ret = -ENOMEM;
794                         goto out;
795                 }
796                 ios->per_dev[i].or = or;
797                 ios->numdevs++;
798
799                 osd_req_remove_object(or, _ios_obj(ios, i));
800         }
801         ret = ore_io_execute(ios);
802
803 out:
804         return ret;
805 }
806 EXPORT_SYMBOL(ore_remove);
807
808 static int _write_mirror(struct ore_io_state *ios, int cur_comp)
809 {
810         struct ore_per_dev_state *master_dev = &ios->per_dev[cur_comp];
811         unsigned dev = ios->per_dev[cur_comp].dev;
812         unsigned last_comp = cur_comp + ios->layout->mirrors_p1;
813         int ret = 0;
814
815         if (ios->pages && !master_dev->length)
816                 return 0; /* Just an empty slot */
817
818         for (; cur_comp < last_comp; ++cur_comp, ++dev) {
819                 struct ore_per_dev_state *per_dev = &ios->per_dev[cur_comp];
820                 struct osd_request *or;
821
822                 or = osd_start_request(_ios_od(ios, dev), GFP_KERNEL);
823                 if (unlikely(!or)) {
824                         ORE_ERR("%s: osd_start_request failed\n", __func__);
825                         ret = -ENOMEM;
826                         goto out;
827                 }
828                 per_dev->or = or;
829
830                 if (ios->pages) {
831                         struct bio *bio;
832
833                         if (per_dev != master_dev) {
834                                 bio = bio_clone_kmalloc(master_dev->bio,
835                                                         GFP_KERNEL);
836                                 if (unlikely(!bio)) {
837                                         ORE_DBGMSG(
838                                               "Failed to allocate BIO size=%u\n",
839                                               master_dev->bio->bi_max_vecs);
840                                         ret = -ENOMEM;
841                                         goto out;
842                                 }
843
844                                 bio->bi_bdev = NULL;
845                                 bio->bi_next = NULL;
846                                 per_dev->offset = master_dev->offset;
847                                 per_dev->length = master_dev->length;
848                                 per_dev->bio =  bio;
849                                 per_dev->dev = dev;
850                         } else {
851                                 bio = master_dev->bio;
852                                 /* FIXME: bio_set_dir() */
853                                 bio->bi_rw |= REQ_WRITE;
854                         }
855
856                         osd_req_write(or, _ios_obj(ios, cur_comp),
857                                       per_dev->offset, bio, per_dev->length);
858                         ORE_DBGMSG("write(0x%llx) offset=0x%llx "
859                                       "length=0x%llx dev=%d\n",
860                                      _LLU(_ios_obj(ios, cur_comp)->id),
861                                      _LLU(per_dev->offset),
862                                      _LLU(per_dev->length), dev);
863                 } else if (ios->kern_buff) {
864                         per_dev->offset = ios->si.obj_offset;
865                         per_dev->dev = ios->si.dev + dev;
866
867                         /* no cross device without page array */
868                         BUG_ON((ios->layout->group_width > 1) &&
869                                (ios->si.unit_off + ios->length >
870                                 ios->layout->stripe_unit));
871
872                         ret = osd_req_write_kern(or, _ios_obj(ios, cur_comp),
873                                                  per_dev->offset,
874                                                  ios->kern_buff, ios->length);
875                         if (unlikely(ret))
876                                 goto out;
877                         ORE_DBGMSG2("write_kern(0x%llx) offset=0x%llx "
878                                       "length=0x%llx dev=%d\n",
879                                      _LLU(_ios_obj(ios, cur_comp)->id),
880                                      _LLU(per_dev->offset),
881                                      _LLU(ios->length), per_dev->dev);
882                 } else {
883                         osd_req_set_attributes(or, _ios_obj(ios, cur_comp));
884                         ORE_DBGMSG2("obj(0x%llx) set_attributes=%d dev=%d\n",
885                                      _LLU(_ios_obj(ios, cur_comp)->id),
886                                      ios->out_attr_len, dev);
887                 }
888
889                 if (ios->out_attr)
890                         osd_req_add_set_attr_list(or, ios->out_attr,
891                                                   ios->out_attr_len);
892
893                 if (ios->in_attr)
894                         osd_req_add_get_attr_list(or, ios->in_attr,
895                                                   ios->in_attr_len);
896         }
897
898 out:
899         return ret;
900 }
901
902 int ore_write(struct ore_io_state *ios)
903 {
904         int i;
905         int ret;
906
907         if (unlikely(ios->sp2d && !ios->r4w)) {
908                 /* A library is attempting a RAID-write without providing
909                  * a pages lock interface.
910                  */
911                 WARN_ON_ONCE(1);
912                 return -ENOTSUPP;
913         }
914
915         ret = _prepare_for_striping(ios);
916         if (unlikely(ret))
917                 return ret;
918
919         for (i = 0; i < ios->numdevs; i += ios->layout->mirrors_p1) {
920                 ret = _write_mirror(ios, i);
921                 if (unlikely(ret))
922                         return ret;
923         }
924
925         ret = ore_io_execute(ios);
926         return ret;
927 }
928 EXPORT_SYMBOL(ore_write);
929
930 int _ore_read_mirror(struct ore_io_state *ios, unsigned cur_comp)
931 {
932         struct osd_request *or;
933         struct ore_per_dev_state *per_dev = &ios->per_dev[cur_comp];
934         struct osd_obj_id *obj = _ios_obj(ios, cur_comp);
935         unsigned first_dev = (unsigned)obj->id;
936
937         if (ios->pages && !per_dev->length)
938                 return 0; /* Just an empty slot */
939
940         first_dev = per_dev->dev + first_dev % ios->layout->mirrors_p1;
941         or = osd_start_request(_ios_od(ios, first_dev), GFP_KERNEL);
942         if (unlikely(!or)) {
943                 ORE_ERR("%s: osd_start_request failed\n", __func__);
944                 return -ENOMEM;
945         }
946         per_dev->or = or;
947
948         if (ios->pages) {
949                 if (per_dev->cur_sg) {
950                         /* finalize the last sg_entry */
951                         _ore_add_sg_seg(per_dev, 0, false);
952                         if (unlikely(!per_dev->cur_sg))
953                                 return 0; /* Skip parity only device */
954
955                         osd_req_read_sg(or, obj, per_dev->bio,
956                                         per_dev->sglist, per_dev->cur_sg);
957                 } else {
958                         /* The no raid case */
959                         osd_req_read(or, obj, per_dev->offset,
960                                      per_dev->bio, per_dev->length);
961                 }
962
963                 ORE_DBGMSG("read(0x%llx) offset=0x%llx length=0x%llx"
964                              " dev=%d sg_len=%d\n", _LLU(obj->id),
965                              _LLU(per_dev->offset), _LLU(per_dev->length),
966                              first_dev, per_dev->cur_sg);
967         } else {
968                 BUG_ON(ios->kern_buff);
969
970                 osd_req_get_attributes(or, obj);
971                 ORE_DBGMSG2("obj(0x%llx) get_attributes=%d dev=%d\n",
972                               _LLU(obj->id),
973                               ios->in_attr_len, first_dev);
974         }
975         if (ios->out_attr)
976                 osd_req_add_set_attr_list(or, ios->out_attr, ios->out_attr_len);
977
978         if (ios->in_attr)
979                 osd_req_add_get_attr_list(or, ios->in_attr, ios->in_attr_len);
980
981         return 0;
982 }
983
984 int ore_read(struct ore_io_state *ios)
985 {
986         int i;
987         int ret;
988
989         ret = _prepare_for_striping(ios);
990         if (unlikely(ret))
991                 return ret;
992
993         for (i = 0; i < ios->numdevs; i += ios->layout->mirrors_p1) {
994                 ret = _ore_read_mirror(ios, i);
995                 if (unlikely(ret))
996                         return ret;
997         }
998
999         ret = ore_io_execute(ios);
1000         return ret;
1001 }
1002 EXPORT_SYMBOL(ore_read);
1003
1004 int extract_attr_from_ios(struct ore_io_state *ios, struct osd_attr *attr)
1005 {
1006         struct osd_attr cur_attr = {.attr_page = 0}; /* start with zeros */
1007         void *iter = NULL;
1008         int nelem;
1009
1010         do {
1011                 nelem = 1;
1012                 osd_req_decode_get_attr_list(ios->per_dev[0].or,
1013                                              &cur_attr, &nelem, &iter);
1014                 if ((cur_attr.attr_page == attr->attr_page) &&
1015                     (cur_attr.attr_id == attr->attr_id)) {
1016                         attr->len = cur_attr.len;
1017                         attr->val_ptr = cur_attr.val_ptr;
1018                         return 0;
1019                 }
1020         } while (iter);
1021
1022         return -EIO;
1023 }
1024 EXPORT_SYMBOL(extract_attr_from_ios);
1025
1026 static int _truncate_mirrors(struct ore_io_state *ios, unsigned cur_comp,
1027                              struct osd_attr *attr)
1028 {
1029         int last_comp = cur_comp + ios->layout->mirrors_p1;
1030
1031         for (; cur_comp < last_comp; ++cur_comp) {
1032                 struct ore_per_dev_state *per_dev = &ios->per_dev[cur_comp];
1033                 struct osd_request *or;
1034
1035                 or = osd_start_request(_ios_od(ios, cur_comp), GFP_KERNEL);
1036                 if (unlikely(!or)) {
1037                         ORE_ERR("%s: osd_start_request failed\n", __func__);
1038                         return -ENOMEM;
1039                 }
1040                 per_dev->or = or;
1041
1042                 osd_req_set_attributes(or, _ios_obj(ios, cur_comp));
1043                 osd_req_add_set_attr_list(or, attr, 1);
1044         }
1045
1046         return 0;
1047 }
1048
1049 struct _trunc_info {
1050         struct ore_striping_info si;
1051         u64 prev_group_obj_off;
1052         u64 next_group_obj_off;
1053
1054         unsigned first_group_dev;
1055         unsigned nex_group_dev;
1056 };
1057
1058 static void _calc_trunk_info(struct ore_layout *layout, u64 file_offset,
1059                              struct _trunc_info *ti)
1060 {
1061         unsigned stripe_unit = layout->stripe_unit;
1062
1063         ore_calc_stripe_info(layout, file_offset, 0, &ti->si);
1064
1065         ti->prev_group_obj_off = ti->si.M * stripe_unit;
1066         ti->next_group_obj_off = ti->si.M ? (ti->si.M - 1) * stripe_unit : 0;
1067
1068         ti->first_group_dev = ti->si.dev - (ti->si.dev % layout->group_width);
1069         ti->nex_group_dev = ti->first_group_dev + layout->group_width;
1070 }
1071
1072 int ore_truncate(struct ore_layout *layout, struct ore_components *oc,
1073                    u64 size)
1074 {
1075         struct ore_io_state *ios;
1076         struct exofs_trunc_attr {
1077                 struct osd_attr attr;
1078                 __be64 newsize;
1079         } *size_attrs;
1080         struct _trunc_info ti;
1081         int i, ret;
1082
1083         ret = ore_get_io_state(layout, oc, &ios);
1084         if (unlikely(ret))
1085                 return ret;
1086
1087         _calc_trunk_info(ios->layout, size, &ti);
1088
1089         size_attrs = kcalloc(ios->oc->numdevs, sizeof(*size_attrs),
1090                              GFP_KERNEL);
1091         if (unlikely(!size_attrs)) {
1092                 ret = -ENOMEM;
1093                 goto out;
1094         }
1095
1096         ios->numdevs = ios->oc->numdevs;
1097
1098         for (i = 0; i < ios->numdevs; ++i) {
1099                 struct exofs_trunc_attr *size_attr = &size_attrs[i];
1100                 u64 obj_size;
1101
1102                 if (i < ti.first_group_dev)
1103                         obj_size = ti.prev_group_obj_off;
1104                 else if (i >= ti.nex_group_dev)
1105                         obj_size = ti.next_group_obj_off;
1106                 else if (i < ti.si.dev) /* dev within this group */
1107                         obj_size = ti.si.obj_offset +
1108                                       ios->layout->stripe_unit - ti.si.unit_off;
1109                 else if (i == ti.si.dev)
1110                         obj_size = ti.si.obj_offset;
1111                 else /* i > ti.dev */
1112                         obj_size = ti.si.obj_offset - ti.si.unit_off;
1113
1114                 size_attr->newsize = cpu_to_be64(obj_size);
1115                 size_attr->attr = g_attr_logical_length;
1116                 size_attr->attr.val_ptr = &size_attr->newsize;
1117
1118                 ORE_DBGMSG2("trunc(0x%llx) obj_offset=0x%llx dev=%d\n",
1119                              _LLU(oc->comps->obj.id), _LLU(obj_size), i);
1120                 ret = _truncate_mirrors(ios, i * ios->layout->mirrors_p1,
1121                                         &size_attr->attr);
1122                 if (unlikely(ret))
1123                         goto out;
1124         }
1125         ret = ore_io_execute(ios);
1126
1127 out:
1128         kfree(size_attrs);
1129         ore_put_io_state(ios);
1130         return ret;
1131 }
1132 EXPORT_SYMBOL(ore_truncate);
1133
1134 const struct osd_attr g_attr_logical_length = ATTR_DEF(
1135         OSD_APAGE_OBJECT_INFORMATION, OSD_ATTR_OI_LOGICAL_LENGTH, 8);
1136 EXPORT_SYMBOL(g_attr_logical_length);