1 /*
2 * Copyright (C) 2016 CNEX Labs
3 * Initial release: Javier Gonzalez <javier@cnexlabs.com>
4 * Matias Bjorling <matias@cnexlabs.com>
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License version
8 * 2 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 for more details.
14 *
15 * pblk-write.c - pblk's write path from write buffer to media
16 */
17
18 #include "pblk.h"
19
pblk_end_w_bio(struct pblk * pblk,struct nvm_rq * rqd,struct pblk_c_ctx * c_ctx)20 static unsigned long pblk_end_w_bio(struct pblk *pblk, struct nvm_rq *rqd,
21 struct pblk_c_ctx *c_ctx)
22 {
23 struct bio *original_bio;
24 struct pblk_rb *rwb = &pblk->rwb;
25 unsigned long ret;
26 int i;
27
28 for (i = 0; i < c_ctx->nr_valid; i++) {
29 struct pblk_w_ctx *w_ctx;
30 int pos = c_ctx->sentry + i;
31 int flags;
32
33 w_ctx = pblk_rb_w_ctx(rwb, pos);
34 flags = READ_ONCE(w_ctx->flags);
35
36 if (flags & PBLK_FLUSH_ENTRY) {
37 flags &= ~PBLK_FLUSH_ENTRY;
38 /* Release flags on context. Protect from writes */
39 smp_store_release(&w_ctx->flags, flags);
40
41 #ifdef CONFIG_NVM_PBLK_DEBUG
42 atomic_dec(&rwb->inflight_flush_point);
43 #endif
44 }
45
46 while ((original_bio = bio_list_pop(&w_ctx->bios)))
47 bio_endio(original_bio);
48 }
49
50 if (c_ctx->nr_padded)
51 pblk_bio_free_pages(pblk, rqd->bio, c_ctx->nr_valid,
52 c_ctx->nr_padded);
53
54 #ifdef CONFIG_NVM_PBLK_DEBUG
55 atomic_long_add(rqd->nr_ppas, &pblk->sync_writes);
56 #endif
57
58 ret = pblk_rb_sync_advance(&pblk->rwb, c_ctx->nr_valid);
59
60 bio_put(rqd->bio);
61 pblk_free_rqd(pblk, rqd, PBLK_WRITE);
62
63 return ret;
64 }
65
pblk_end_queued_w_bio(struct pblk * pblk,struct nvm_rq * rqd,struct pblk_c_ctx * c_ctx)66 static unsigned long pblk_end_queued_w_bio(struct pblk *pblk,
67 struct nvm_rq *rqd,
68 struct pblk_c_ctx *c_ctx)
69 {
70 list_del(&c_ctx->list);
71 return pblk_end_w_bio(pblk, rqd, c_ctx);
72 }
73
pblk_complete_write(struct pblk * pblk,struct nvm_rq * rqd,struct pblk_c_ctx * c_ctx)74 static void pblk_complete_write(struct pblk *pblk, struct nvm_rq *rqd,
75 struct pblk_c_ctx *c_ctx)
76 {
77 struct pblk_c_ctx *c, *r;
78 unsigned long flags;
79 unsigned long pos;
80
81 #ifdef CONFIG_NVM_PBLK_DEBUG
82 atomic_long_sub(c_ctx->nr_valid, &pblk->inflight_writes);
83 #endif
84
85 pblk_up_rq(pblk, rqd->ppa_list, rqd->nr_ppas, c_ctx->lun_bitmap);
86
87 pos = pblk_rb_sync_init(&pblk->rwb, &flags);
88 if (pos == c_ctx->sentry) {
89 pos = pblk_end_w_bio(pblk, rqd, c_ctx);
90
91 retry:
92 list_for_each_entry_safe(c, r, &pblk->compl_list, list) {
93 rqd = nvm_rq_from_c_ctx(c);
94 if (c->sentry == pos) {
95 pos = pblk_end_queued_w_bio(pblk, rqd, c);
96 goto retry;
97 }
98 }
99 } else {
100 WARN_ON(nvm_rq_from_c_ctx(c_ctx) != rqd);
101 list_add_tail(&c_ctx->list, &pblk->compl_list);
102 }
103 pblk_rb_sync_end(&pblk->rwb, &flags);
104 }
105
106 /* Map remaining sectors in chunk, starting from ppa */
pblk_map_remaining(struct pblk * pblk,struct ppa_addr * ppa)107 static void pblk_map_remaining(struct pblk *pblk, struct ppa_addr *ppa)
108 {
109 struct nvm_tgt_dev *dev = pblk->dev;
110 struct nvm_geo *geo = &dev->geo;
111 struct pblk_line *line;
112 struct ppa_addr map_ppa = *ppa;
113 u64 paddr;
114 int done = 0;
115
116 line = &pblk->lines[pblk_ppa_to_line(*ppa)];
117 spin_lock(&line->lock);
118
119 while (!done) {
120 paddr = pblk_dev_ppa_to_line_addr(pblk, map_ppa);
121
122 if (!test_and_set_bit(paddr, line->map_bitmap))
123 line->left_msecs--;
124
125 if (!test_and_set_bit(paddr, line->invalid_bitmap))
126 le32_add_cpu(line->vsc, -1);
127
128 if (geo->version == NVM_OCSSD_SPEC_12) {
129 map_ppa.ppa++;
130 if (map_ppa.g.pg == geo->num_pg)
131 done = 1;
132 } else {
133 map_ppa.m.sec++;
134 if (map_ppa.m.sec == geo->clba)
135 done = 1;
136 }
137 }
138
139 line->w_err_gc->has_write_err = 1;
140 spin_unlock(&line->lock);
141 }
142
pblk_prepare_resubmit(struct pblk * pblk,unsigned int sentry,unsigned int nr_entries)143 static void pblk_prepare_resubmit(struct pblk *pblk, unsigned int sentry,
144 unsigned int nr_entries)
145 {
146 struct pblk_rb *rb = &pblk->rwb;
147 struct pblk_rb_entry *entry;
148 struct pblk_line *line;
149 struct pblk_w_ctx *w_ctx;
150 struct ppa_addr ppa_l2p;
151 int flags;
152 unsigned int pos, i;
153
154 spin_lock(&pblk->trans_lock);
155 pos = sentry;
156 for (i = 0; i < nr_entries; i++) {
157 entry = &rb->entries[pos];
158 w_ctx = &entry->w_ctx;
159
160 /* Check if the lba has been overwritten */
161 if (w_ctx->lba != ADDR_EMPTY) {
162 ppa_l2p = pblk_trans_map_get(pblk, w_ctx->lba);
163 if (!pblk_ppa_comp(ppa_l2p, entry->cacheline))
164 w_ctx->lba = ADDR_EMPTY;
165 }
166
167 /* Mark up the entry as submittable again */
168 flags = READ_ONCE(w_ctx->flags);
169 flags |= PBLK_WRITTEN_DATA;
170 /* Release flags on write context. Protect from writes */
171 smp_store_release(&w_ctx->flags, flags);
172
173 /* Decrese the reference count to the line as we will
174 * re-map these entries
175 */
176 line = &pblk->lines[pblk_ppa_to_line(w_ctx->ppa)];
177 kref_put(&line->ref, pblk_line_put);
178
179 pos = (pos + 1) & (rb->nr_entries - 1);
180 }
181 spin_unlock(&pblk->trans_lock);
182 }
183
pblk_queue_resubmit(struct pblk * pblk,struct pblk_c_ctx * c_ctx)184 static void pblk_queue_resubmit(struct pblk *pblk, struct pblk_c_ctx *c_ctx)
185 {
186 struct pblk_c_ctx *r_ctx;
187
188 r_ctx = kzalloc(sizeof(struct pblk_c_ctx), GFP_KERNEL);
189 if (!r_ctx)
190 return;
191
192 r_ctx->lun_bitmap = NULL;
193 r_ctx->sentry = c_ctx->sentry;
194 r_ctx->nr_valid = c_ctx->nr_valid;
195 r_ctx->nr_padded = c_ctx->nr_padded;
196
197 spin_lock(&pblk->resubmit_lock);
198 list_add_tail(&r_ctx->list, &pblk->resubmit_list);
199 spin_unlock(&pblk->resubmit_lock);
200
201 #ifdef CONFIG_NVM_PBLK_DEBUG
202 atomic_long_add(c_ctx->nr_valid, &pblk->recov_writes);
203 #endif
204 }
205
pblk_submit_rec(struct work_struct * work)206 static void pblk_submit_rec(struct work_struct *work)
207 {
208 struct pblk_rec_ctx *recovery =
209 container_of(work, struct pblk_rec_ctx, ws_rec);
210 struct pblk *pblk = recovery->pblk;
211 struct nvm_rq *rqd = recovery->rqd;
212 struct pblk_c_ctx *c_ctx = nvm_rq_to_pdu(rqd);
213 struct ppa_addr *ppa_list;
214
215 pblk_log_write_err(pblk, rqd);
216
217 if (rqd->nr_ppas == 1)
218 ppa_list = &rqd->ppa_addr;
219 else
220 ppa_list = rqd->ppa_list;
221
222 pblk_map_remaining(pblk, ppa_list);
223 pblk_queue_resubmit(pblk, c_ctx);
224
225 pblk_up_rq(pblk, rqd->ppa_list, rqd->nr_ppas, c_ctx->lun_bitmap);
226 if (c_ctx->nr_padded)
227 pblk_bio_free_pages(pblk, rqd->bio, c_ctx->nr_valid,
228 c_ctx->nr_padded);
229 bio_put(rqd->bio);
230 pblk_free_rqd(pblk, rqd, PBLK_WRITE);
231 mempool_free(recovery, &pblk->rec_pool);
232
233 atomic_dec(&pblk->inflight_io);
234 }
235
236
pblk_end_w_fail(struct pblk * pblk,struct nvm_rq * rqd)237 static void pblk_end_w_fail(struct pblk *pblk, struct nvm_rq *rqd)
238 {
239 struct pblk_rec_ctx *recovery;
240
241 recovery = mempool_alloc(&pblk->rec_pool, GFP_ATOMIC);
242 if (!recovery) {
243 pblk_err(pblk, "could not allocate recovery work\n");
244 return;
245 }
246
247 recovery->pblk = pblk;
248 recovery->rqd = rqd;
249
250 INIT_WORK(&recovery->ws_rec, pblk_submit_rec);
251 queue_work(pblk->close_wq, &recovery->ws_rec);
252 }
253
pblk_end_io_write(struct nvm_rq * rqd)254 static void pblk_end_io_write(struct nvm_rq *rqd)
255 {
256 struct pblk *pblk = rqd->private;
257 struct pblk_c_ctx *c_ctx = nvm_rq_to_pdu(rqd);
258
259 if (rqd->error) {
260 pblk_end_w_fail(pblk, rqd);
261 return;
262 }
263 #ifdef CONFIG_NVM_PBLK_DEBUG
264 else
265 WARN_ONCE(rqd->bio->bi_status, "pblk: corrupted write error\n");
266 #endif
267
268 pblk_complete_write(pblk, rqd, c_ctx);
269 atomic_dec(&pblk->inflight_io);
270 }
271
pblk_end_io_write_meta(struct nvm_rq * rqd)272 static void pblk_end_io_write_meta(struct nvm_rq *rqd)
273 {
274 struct pblk *pblk = rqd->private;
275 struct pblk_g_ctx *m_ctx = nvm_rq_to_pdu(rqd);
276 struct pblk_line *line = m_ctx->private;
277 struct pblk_emeta *emeta = line->emeta;
278 int sync;
279
280 pblk_up_page(pblk, rqd->ppa_list, rqd->nr_ppas);
281
282 if (rqd->error) {
283 pblk_log_write_err(pblk, rqd);
284 pblk_err(pblk, "metadata I/O failed. Line %d\n", line->id);
285 line->w_err_gc->has_write_err = 1;
286 }
287
288 sync = atomic_add_return(rqd->nr_ppas, &emeta->sync);
289 if (sync == emeta->nr_entries)
290 pblk_gen_run_ws(pblk, line, NULL, pblk_line_close_ws,
291 GFP_ATOMIC, pblk->close_wq);
292
293 pblk_free_rqd(pblk, rqd, PBLK_WRITE_INT);
294
295 atomic_dec(&pblk->inflight_io);
296 }
297
pblk_alloc_w_rq(struct pblk * pblk,struct nvm_rq * rqd,unsigned int nr_secs,nvm_end_io_fn (* end_io))298 static int pblk_alloc_w_rq(struct pblk *pblk, struct nvm_rq *rqd,
299 unsigned int nr_secs,
300 nvm_end_io_fn(*end_io))
301 {
302 struct nvm_tgt_dev *dev = pblk->dev;
303
304 /* Setup write request */
305 rqd->opcode = NVM_OP_PWRITE;
306 rqd->nr_ppas = nr_secs;
307 rqd->flags = pblk_set_progr_mode(pblk, PBLK_WRITE);
308 rqd->private = pblk;
309 rqd->end_io = end_io;
310
311 rqd->meta_list = nvm_dev_dma_alloc(dev->parent, GFP_KERNEL,
312 &rqd->dma_meta_list);
313 if (!rqd->meta_list)
314 return -ENOMEM;
315
316 rqd->ppa_list = rqd->meta_list + pblk_dma_meta_size;
317 rqd->dma_ppa_list = rqd->dma_meta_list + pblk_dma_meta_size;
318
319 return 0;
320 }
321
pblk_setup_w_rq(struct pblk * pblk,struct nvm_rq * rqd,struct ppa_addr * erase_ppa)322 static int pblk_setup_w_rq(struct pblk *pblk, struct nvm_rq *rqd,
323 struct ppa_addr *erase_ppa)
324 {
325 struct pblk_line_meta *lm = &pblk->lm;
326 struct pblk_line *e_line = pblk_line_get_erase(pblk);
327 struct pblk_c_ctx *c_ctx = nvm_rq_to_pdu(rqd);
328 unsigned int valid = c_ctx->nr_valid;
329 unsigned int padded = c_ctx->nr_padded;
330 unsigned int nr_secs = valid + padded;
331 unsigned long *lun_bitmap;
332 int ret;
333
334 lun_bitmap = kzalloc(lm->lun_bitmap_len, GFP_KERNEL);
335 if (!lun_bitmap)
336 return -ENOMEM;
337 c_ctx->lun_bitmap = lun_bitmap;
338
339 ret = pblk_alloc_w_rq(pblk, rqd, nr_secs, pblk_end_io_write);
340 if (ret) {
341 kfree(lun_bitmap);
342 return ret;
343 }
344
345 if (likely(!e_line || !atomic_read(&e_line->left_eblks)))
346 pblk_map_rq(pblk, rqd, c_ctx->sentry, lun_bitmap, valid, 0);
347 else
348 pblk_map_erase_rq(pblk, rqd, c_ctx->sentry, lun_bitmap,
349 valid, erase_ppa);
350
351 return 0;
352 }
353
pblk_calc_secs_to_sync(struct pblk * pblk,unsigned int secs_avail,unsigned int secs_to_flush)354 static int pblk_calc_secs_to_sync(struct pblk *pblk, unsigned int secs_avail,
355 unsigned int secs_to_flush)
356 {
357 int secs_to_sync;
358
359 secs_to_sync = pblk_calc_secs(pblk, secs_avail, secs_to_flush);
360
361 #ifdef CONFIG_NVM_PBLK_DEBUG
362 if ((!secs_to_sync && secs_to_flush)
363 || (secs_to_sync < 0)
364 || (secs_to_sync > secs_avail && !secs_to_flush)) {
365 pblk_err(pblk, "bad sector calculation (a:%d,s:%d,f:%d)\n",
366 secs_avail, secs_to_sync, secs_to_flush);
367 }
368 #endif
369
370 return secs_to_sync;
371 }
372
pblk_submit_meta_io(struct pblk * pblk,struct pblk_line * meta_line)373 int pblk_submit_meta_io(struct pblk *pblk, struct pblk_line *meta_line)
374 {
375 struct nvm_tgt_dev *dev = pblk->dev;
376 struct nvm_geo *geo = &dev->geo;
377 struct pblk_line_mgmt *l_mg = &pblk->l_mg;
378 struct pblk_line_meta *lm = &pblk->lm;
379 struct pblk_emeta *emeta = meta_line->emeta;
380 struct pblk_g_ctx *m_ctx;
381 struct bio *bio;
382 struct nvm_rq *rqd;
383 void *data;
384 u64 paddr;
385 int rq_ppas = pblk->min_write_pgs;
386 int id = meta_line->id;
387 int rq_len;
388 int i, j;
389 int ret;
390
391 rqd = pblk_alloc_rqd(pblk, PBLK_WRITE_INT);
392
393 m_ctx = nvm_rq_to_pdu(rqd);
394 m_ctx->private = meta_line;
395
396 rq_len = rq_ppas * geo->csecs;
397 data = ((void *)emeta->buf) + emeta->mem;
398
399 bio = pblk_bio_map_addr(pblk, data, rq_ppas, rq_len,
400 l_mg->emeta_alloc_type, GFP_KERNEL);
401 if (IS_ERR(bio)) {
402 pblk_err(pblk, "failed to map emeta io");
403 ret = PTR_ERR(bio);
404 goto fail_free_rqd;
405 }
406 bio->bi_iter.bi_sector = 0; /* internal bio */
407 bio_set_op_attrs(bio, REQ_OP_WRITE, 0);
408 rqd->bio = bio;
409
410 ret = pblk_alloc_w_rq(pblk, rqd, rq_ppas, pblk_end_io_write_meta);
411 if (ret)
412 goto fail_free_bio;
413
414 for (i = 0; i < rqd->nr_ppas; ) {
415 spin_lock(&meta_line->lock);
416 paddr = __pblk_alloc_page(pblk, meta_line, rq_ppas);
417 spin_unlock(&meta_line->lock);
418 for (j = 0; j < rq_ppas; j++, i++, paddr++)
419 rqd->ppa_list[i] = addr_to_gen_ppa(pblk, paddr, id);
420 }
421
422 spin_lock(&l_mg->close_lock);
423 emeta->mem += rq_len;
424 if (emeta->mem >= lm->emeta_len[0])
425 list_del(&meta_line->list);
426 spin_unlock(&l_mg->close_lock);
427
428 pblk_down_page(pblk, rqd->ppa_list, rqd->nr_ppas);
429
430 ret = pblk_submit_io(pblk, rqd);
431 if (ret) {
432 pblk_err(pblk, "emeta I/O submission failed: %d\n", ret);
433 goto fail_rollback;
434 }
435
436 return NVM_IO_OK;
437
438 fail_rollback:
439 pblk_up_page(pblk, rqd->ppa_list, rqd->nr_ppas);
440 spin_lock(&l_mg->close_lock);
441 pblk_dealloc_page(pblk, meta_line, rq_ppas);
442 list_add(&meta_line->list, &meta_line->list);
443 spin_unlock(&l_mg->close_lock);
444 fail_free_bio:
445 bio_put(bio);
446 fail_free_rqd:
447 pblk_free_rqd(pblk, rqd, PBLK_WRITE_INT);
448 return ret;
449 }
450
pblk_valid_meta_ppa(struct pblk * pblk,struct pblk_line * meta_line,struct nvm_rq * data_rqd)451 static inline bool pblk_valid_meta_ppa(struct pblk *pblk,
452 struct pblk_line *meta_line,
453 struct nvm_rq *data_rqd)
454 {
455 struct nvm_tgt_dev *dev = pblk->dev;
456 struct nvm_geo *geo = &dev->geo;
457 struct pblk_c_ctx *data_c_ctx = nvm_rq_to_pdu(data_rqd);
458 struct pblk_line *data_line = pblk_line_get_data(pblk);
459 struct ppa_addr ppa, ppa_opt;
460 u64 paddr;
461 int pos_opt;
462
463 /* Schedule a metadata I/O that is half the distance from the data I/O
464 * with regards to the number of LUNs forming the pblk instance. This
465 * balances LUN conflicts across every I/O.
466 *
467 * When the LUN configuration changes (e.g., due to GC), this distance
468 * can align, which would result on metadata and data I/Os colliding. In
469 * this case, modify the distance to not be optimal, but move the
470 * optimal in the right direction.
471 */
472 paddr = pblk_lookup_page(pblk, meta_line);
473 ppa = addr_to_gen_ppa(pblk, paddr, 0);
474 ppa_opt = addr_to_gen_ppa(pblk, paddr + data_line->meta_distance, 0);
475 pos_opt = pblk_ppa_to_pos(geo, ppa_opt);
476
477 if (test_bit(pos_opt, data_c_ctx->lun_bitmap) ||
478 test_bit(pos_opt, data_line->blk_bitmap))
479 return true;
480
481 if (unlikely(pblk_ppa_comp(ppa_opt, ppa)))
482 data_line->meta_distance--;
483
484 return false;
485 }
486
pblk_should_submit_meta_io(struct pblk * pblk,struct nvm_rq * data_rqd)487 static struct pblk_line *pblk_should_submit_meta_io(struct pblk *pblk,
488 struct nvm_rq *data_rqd)
489 {
490 struct pblk_line_meta *lm = &pblk->lm;
491 struct pblk_line_mgmt *l_mg = &pblk->l_mg;
492 struct pblk_line *meta_line;
493
494 spin_lock(&l_mg->close_lock);
495 if (list_empty(&l_mg->emeta_list)) {
496 spin_unlock(&l_mg->close_lock);
497 return NULL;
498 }
499 meta_line = list_first_entry(&l_mg->emeta_list, struct pblk_line, list);
500 if (meta_line->emeta->mem >= lm->emeta_len[0]) {
501 spin_unlock(&l_mg->close_lock);
502 return NULL;
503 }
504 spin_unlock(&l_mg->close_lock);
505
506 if (!pblk_valid_meta_ppa(pblk, meta_line, data_rqd))
507 return NULL;
508
509 return meta_line;
510 }
511
pblk_submit_io_set(struct pblk * pblk,struct nvm_rq * rqd)512 static int pblk_submit_io_set(struct pblk *pblk, struct nvm_rq *rqd)
513 {
514 struct ppa_addr erase_ppa;
515 struct pblk_line *meta_line;
516 int err;
517
518 pblk_ppa_set_empty(&erase_ppa);
519
520 /* Assign lbas to ppas and populate request structure */
521 err = pblk_setup_w_rq(pblk, rqd, &erase_ppa);
522 if (err) {
523 pblk_err(pblk, "could not setup write request: %d\n", err);
524 return NVM_IO_ERR;
525 }
526
527 meta_line = pblk_should_submit_meta_io(pblk, rqd);
528
529 /* Submit data write for current data line */
530 err = pblk_submit_io(pblk, rqd);
531 if (err) {
532 pblk_err(pblk, "data I/O submission failed: %d\n", err);
533 return NVM_IO_ERR;
534 }
535
536 if (!pblk_ppa_empty(erase_ppa)) {
537 /* Submit erase for next data line */
538 if (pblk_blk_erase_async(pblk, erase_ppa)) {
539 struct pblk_line *e_line = pblk_line_get_erase(pblk);
540 struct nvm_tgt_dev *dev = pblk->dev;
541 struct nvm_geo *geo = &dev->geo;
542 int bit;
543
544 atomic_inc(&e_line->left_eblks);
545 bit = pblk_ppa_to_pos(geo, erase_ppa);
546 WARN_ON(!test_and_clear_bit(bit, e_line->erase_bitmap));
547 }
548 }
549
550 if (meta_line) {
551 /* Submit metadata write for previous data line */
552 err = pblk_submit_meta_io(pblk, meta_line);
553 if (err) {
554 pblk_err(pblk, "metadata I/O submission failed: %d",
555 err);
556 return NVM_IO_ERR;
557 }
558 }
559
560 return NVM_IO_OK;
561 }
562
pblk_free_write_rqd(struct pblk * pblk,struct nvm_rq * rqd)563 static void pblk_free_write_rqd(struct pblk *pblk, struct nvm_rq *rqd)
564 {
565 struct pblk_c_ctx *c_ctx = nvm_rq_to_pdu(rqd);
566 struct bio *bio = rqd->bio;
567
568 if (c_ctx->nr_padded)
569 pblk_bio_free_pages(pblk, bio, c_ctx->nr_valid,
570 c_ctx->nr_padded);
571 }
572
pblk_submit_write(struct pblk * pblk)573 static int pblk_submit_write(struct pblk *pblk)
574 {
575 struct bio *bio;
576 struct nvm_rq *rqd;
577 unsigned int secs_avail, secs_to_sync, secs_to_com;
578 unsigned int secs_to_flush;
579 unsigned long pos;
580 unsigned int resubmit;
581
582 spin_lock(&pblk->resubmit_lock);
583 resubmit = !list_empty(&pblk->resubmit_list);
584 spin_unlock(&pblk->resubmit_lock);
585
586 /* Resubmit failed writes first */
587 if (resubmit) {
588 struct pblk_c_ctx *r_ctx;
589
590 spin_lock(&pblk->resubmit_lock);
591 r_ctx = list_first_entry(&pblk->resubmit_list,
592 struct pblk_c_ctx, list);
593 list_del(&r_ctx->list);
594 spin_unlock(&pblk->resubmit_lock);
595
596 secs_avail = r_ctx->nr_valid;
597 pos = r_ctx->sentry;
598
599 pblk_prepare_resubmit(pblk, pos, secs_avail);
600 secs_to_sync = pblk_calc_secs_to_sync(pblk, secs_avail,
601 secs_avail);
602
603 kfree(r_ctx);
604 } else {
605 /* If there are no sectors in the cache,
606 * flushes (bios without data) will be cleared on
607 * the cache threads
608 */
609 secs_avail = pblk_rb_read_count(&pblk->rwb);
610 if (!secs_avail)
611 return 1;
612
613 secs_to_flush = pblk_rb_flush_point_count(&pblk->rwb);
614 if (!secs_to_flush && secs_avail < pblk->min_write_pgs)
615 return 1;
616
617 secs_to_sync = pblk_calc_secs_to_sync(pblk, secs_avail,
618 secs_to_flush);
619 if (secs_to_sync > pblk->max_write_pgs) {
620 pblk_err(pblk, "bad buffer sync calculation\n");
621 return 1;
622 }
623
624 secs_to_com = (secs_to_sync > secs_avail) ?
625 secs_avail : secs_to_sync;
626 pos = pblk_rb_read_commit(&pblk->rwb, secs_to_com);
627 }
628
629 bio = bio_alloc(GFP_KERNEL, secs_to_sync);
630
631 bio->bi_iter.bi_sector = 0; /* internal bio */
632 bio_set_op_attrs(bio, REQ_OP_WRITE, 0);
633
634 rqd = pblk_alloc_rqd(pblk, PBLK_WRITE);
635 rqd->bio = bio;
636
637 if (pblk_rb_read_to_bio(&pblk->rwb, rqd, pos, secs_to_sync,
638 secs_avail)) {
639 pblk_err(pblk, "corrupted write bio\n");
640 goto fail_put_bio;
641 }
642
643 if (pblk_submit_io_set(pblk, rqd))
644 goto fail_free_bio;
645
646 #ifdef CONFIG_NVM_PBLK_DEBUG
647 atomic_long_add(secs_to_sync, &pblk->sub_writes);
648 #endif
649
650 return 0;
651
652 fail_free_bio:
653 pblk_free_write_rqd(pblk, rqd);
654 fail_put_bio:
655 bio_put(bio);
656 pblk_free_rqd(pblk, rqd, PBLK_WRITE);
657
658 return 1;
659 }
660
pblk_write_ts(void * data)661 int pblk_write_ts(void *data)
662 {
663 struct pblk *pblk = data;
664
665 while (!kthread_should_stop()) {
666 if (!pblk_submit_write(pblk))
667 continue;
668 set_current_state(TASK_INTERRUPTIBLE);
669 io_schedule();
670 }
671
672 return 0;
673 }
674