/* * Copyright (C) 2016 CNEX Labs * Initial release: Javier Gonzalez <javier@cnexlabs.com> * Matias Bjorling <matias@cnexlabs.com> * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License version * 2 as published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * pblk-write.c - pblk's write path from write buffer to media */ #include "pblk.h" static unsigned long pblk_end_w_bio(struct pblk *pblk, struct nvm_rq *rqd, struct pblk_c_ctx *c_ctx) { struct bio *original_bio; unsigned long ret; int i; for (i = 0; i < c_ctx->nr_valid; i++) { struct pblk_w_ctx *w_ctx; w_ctx = pblk_rb_w_ctx(&pblk->rwb, c_ctx->sentry + i); while ((original_bio = bio_list_pop(&w_ctx->bios))) bio_endio(original_bio); } if (c_ctx->nr_padded) pblk_bio_free_pages(pblk, rqd->bio, c_ctx->nr_valid, c_ctx->nr_padded); #ifdef CONFIG_NVM_DEBUG atomic_long_add(rqd->nr_ppas, &pblk->sync_writes); #endif ret = pblk_rb_sync_advance(&pblk->rwb, c_ctx->nr_valid); bio_put(rqd->bio); pblk_free_rqd(pblk, rqd, PBLK_WRITE); return ret; } static unsigned long pblk_end_queued_w_bio(struct pblk *pblk, struct nvm_rq *rqd, struct pblk_c_ctx *c_ctx) { list_del(&c_ctx->list); return pblk_end_w_bio(pblk, rqd, c_ctx); } static void pblk_complete_write(struct pblk *pblk, struct nvm_rq *rqd, struct pblk_c_ctx *c_ctx) { struct pblk_c_ctx *c, *r; unsigned long flags; unsigned long pos; #ifdef CONFIG_NVM_DEBUG atomic_long_sub(c_ctx->nr_valid, &pblk->inflight_writes); #endif pblk_up_rq(pblk, rqd->ppa_list, rqd->nr_ppas, c_ctx->lun_bitmap); pos = pblk_rb_sync_init(&pblk->rwb, &flags); if (pos == c_ctx->sentry) { pos = pblk_end_w_bio(pblk, rqd, c_ctx); retry: list_for_each_entry_safe(c, r, &pblk->compl_list, list) { rqd = nvm_rq_from_c_ctx(c); if (c->sentry == pos) { pos = pblk_end_queued_w_bio(pblk, rqd, c); goto retry; } } } else { WARN_ON(nvm_rq_from_c_ctx(c_ctx) != rqd); list_add_tail(&c_ctx->list, &pblk->compl_list); } pblk_rb_sync_end(&pblk->rwb, &flags); } /* When a write fails, we are not sure whether the block has grown bad or a page * range is more susceptible to write errors. If a high number of pages fail, we * assume that the block is bad and we mark it accordingly. In all cases, we * remap and resubmit the failed entries as fast as possible; if a flush is * waiting on a completion, the whole stack would stall otherwise. */ static void pblk_end_w_fail(struct pblk *pblk, struct nvm_rq *rqd) { void *comp_bits = &rqd->ppa_status; struct pblk_c_ctx *c_ctx = nvm_rq_to_pdu(rqd); struct pblk_rec_ctx *recovery; struct ppa_addr *ppa_list = rqd->ppa_list; int nr_ppas = rqd->nr_ppas; unsigned int c_entries; int bit, ret; if (unlikely(nr_ppas == 1)) ppa_list = &rqd->ppa_addr; recovery = mempool_alloc(pblk->rec_pool, GFP_ATOMIC); INIT_LIST_HEAD(&recovery->failed); bit = -1; while ((bit = find_next_bit(comp_bits, nr_ppas, bit + 1)) < nr_ppas) { struct pblk_rb_entry *entry; struct ppa_addr ppa; /* Logic error */ if (bit > c_ctx->nr_valid) { WARN_ONCE(1, "pblk: corrupted write request\n"); mempool_free(recovery, pblk->rec_pool); goto out; } ppa = ppa_list[bit]; entry = pblk_rb_sync_scan_entry(&pblk->rwb, &ppa); if (!entry) { pr_err("pblk: could not scan entry on write failure\n"); mempool_free(recovery, pblk->rec_pool); goto out; } /* The list is filled first and emptied afterwards. No need for * protecting it with a lock */ list_add_tail(&entry->index, &recovery->failed); } c_entries = find_first_bit(comp_bits, nr_ppas); ret = pblk_recov_setup_rq(pblk, c_ctx, recovery, comp_bits, c_entries); if (ret) { pr_err("pblk: could not recover from write failure\n"); mempool_free(recovery, pblk->rec_pool); goto out; } INIT_WORK(&recovery->ws_rec, pblk_submit_rec); queue_work(pblk->close_wq, &recovery->ws_rec); out: pblk_complete_write(pblk, rqd, c_ctx); } static void pblk_end_io_write(struct nvm_rq *rqd) { struct pblk *pblk = rqd->private; struct pblk_c_ctx *c_ctx = nvm_rq_to_pdu(rqd); if (rqd->error) { pblk_log_write_err(pblk, rqd); return pblk_end_w_fail(pblk, rqd); } #ifdef CONFIG_NVM_DEBUG else WARN_ONCE(rqd->bio->bi_status, "pblk: corrupted write error\n"); #endif pblk_complete_write(pblk, rqd, c_ctx); atomic_dec(&pblk->inflight_io); } static void pblk_end_io_write_meta(struct nvm_rq *rqd) { struct pblk *pblk = rqd->private; struct pblk_g_ctx *m_ctx = nvm_rq_to_pdu(rqd); struct pblk_line *line = m_ctx->private; struct pblk_emeta *emeta = line->emeta; int sync; pblk_up_page(pblk, rqd->ppa_list, rqd->nr_ppas); if (rqd->error) { pblk_log_write_err(pblk, rqd); pr_err("pblk: metadata I/O failed. Line %d\n", line->id); } sync = atomic_add_return(rqd->nr_ppas, &emeta->sync); if (sync == emeta->nr_entries) pblk_gen_run_ws(pblk, line, NULL, pblk_line_close_ws, GFP_ATOMIC, pblk->close_wq); pblk_free_rqd(pblk, rqd, PBLK_WRITE_INT); atomic_dec(&pblk->inflight_io); } static int pblk_alloc_w_rq(struct pblk *pblk, struct nvm_rq *rqd, unsigned int nr_secs, nvm_end_io_fn(*end_io)) { struct nvm_tgt_dev *dev = pblk->dev; /* Setup write request */ rqd->opcode = NVM_OP_PWRITE; rqd->nr_ppas = nr_secs; rqd->flags = pblk_set_progr_mode(pblk, PBLK_WRITE); rqd->private = pblk; rqd->end_io = end_io; rqd->meta_list = nvm_dev_dma_alloc(dev->parent, GFP_KERNEL, &rqd->dma_meta_list); if (!rqd->meta_list) return -ENOMEM; rqd->ppa_list = rqd->meta_list + pblk_dma_meta_size; rqd->dma_ppa_list = rqd->dma_meta_list + pblk_dma_meta_size; return 0; } static int pblk_setup_w_rq(struct pblk *pblk, struct nvm_rq *rqd, struct ppa_addr *erase_ppa) { struct pblk_line_meta *lm = &pblk->lm; struct pblk_line *e_line = pblk_line_get_erase(pblk); struct pblk_c_ctx *c_ctx = nvm_rq_to_pdu(rqd); unsigned int valid = c_ctx->nr_valid; unsigned int padded = c_ctx->nr_padded; unsigned int nr_secs = valid + padded; unsigned long *lun_bitmap; int ret; lun_bitmap = kzalloc(lm->lun_bitmap_len, GFP_KERNEL); if (!lun_bitmap) return -ENOMEM; c_ctx->lun_bitmap = lun_bitmap; ret = pblk_alloc_w_rq(pblk, rqd, nr_secs, pblk_end_io_write); if (ret) { kfree(lun_bitmap); return ret; } if (likely(!e_line || !atomic_read(&e_line->left_eblks))) pblk_map_rq(pblk, rqd, c_ctx->sentry, lun_bitmap, valid, 0); else pblk_map_erase_rq(pblk, rqd, c_ctx->sentry, lun_bitmap, valid, erase_ppa); return 0; } int pblk_setup_w_rec_rq(struct pblk *pblk, struct nvm_rq *rqd, struct pblk_c_ctx *c_ctx) { struct pblk_line_meta *lm = &pblk->lm; unsigned long *lun_bitmap; int ret; lun_bitmap = kzalloc(lm->lun_bitmap_len, GFP_KERNEL); if (!lun_bitmap) return -ENOMEM; c_ctx->lun_bitmap = lun_bitmap; ret = pblk_alloc_w_rq(pblk, rqd, rqd->nr_ppas, pblk_end_io_write); if (ret) return ret; pblk_map_rq(pblk, rqd, c_ctx->sentry, lun_bitmap, c_ctx->nr_valid, 0); rqd->ppa_status = (u64)0; rqd->flags = pblk_set_progr_mode(pblk, PBLK_WRITE); return ret; } static int pblk_calc_secs_to_sync(struct pblk *pblk, unsigned int secs_avail, unsigned int secs_to_flush) { int secs_to_sync; secs_to_sync = pblk_calc_secs(pblk, secs_avail, secs_to_flush); #ifdef CONFIG_NVM_DEBUG if ((!secs_to_sync && secs_to_flush) || (secs_to_sync < 0) || (secs_to_sync > secs_avail && !secs_to_flush)) { pr_err("pblk: bad sector calculation (a:%d,s:%d,f:%d)\n", secs_avail, secs_to_sync, secs_to_flush); } #endif return secs_to_sync; } int pblk_submit_meta_io(struct pblk *pblk, struct pblk_line *meta_line) { struct nvm_tgt_dev *dev = pblk->dev; struct nvm_geo *geo = &dev->geo; struct pblk_line_mgmt *l_mg = &pblk->l_mg; struct pblk_line_meta *lm = &pblk->lm; struct pblk_emeta *emeta = meta_line->emeta; struct pblk_g_ctx *m_ctx; struct bio *bio; struct nvm_rq *rqd; void *data; u64 paddr; int rq_ppas = pblk->min_write_pgs; int id = meta_line->id; int rq_len; int i, j; int ret; rqd = pblk_alloc_rqd(pblk, PBLK_WRITE_INT); m_ctx = nvm_rq_to_pdu(rqd); m_ctx->private = meta_line; rq_len = rq_ppas * geo->sec_size; data = ((void *)emeta->buf) + emeta->mem; bio = pblk_bio_map_addr(pblk, data, rq_ppas, rq_len, l_mg->emeta_alloc_type, GFP_KERNEL); if (IS_ERR(bio)) { ret = PTR_ERR(bio); goto fail_free_rqd; } bio->bi_iter.bi_sector = 0; /* internal bio */ bio_set_op_attrs(bio, REQ_OP_WRITE, 0); rqd->bio = bio; ret = pblk_alloc_w_rq(pblk, rqd, rq_ppas, pblk_end_io_write_meta); if (ret) goto fail_free_bio; for (i = 0; i < rqd->nr_ppas; ) { spin_lock(&meta_line->lock); paddr = __pblk_alloc_page(pblk, meta_line, rq_ppas); spin_unlock(&meta_line->lock); for (j = 0; j < rq_ppas; j++, i++, paddr++) rqd->ppa_list[i] = addr_to_gen_ppa(pblk, paddr, id); } emeta->mem += rq_len; if (emeta->mem >= lm->emeta_len[0]) { spin_lock(&l_mg->close_lock); list_del(&meta_line->list); spin_unlock(&l_mg->close_lock); } pblk_down_page(pblk, rqd->ppa_list, rqd->nr_ppas); ret = pblk_submit_io(pblk, rqd); if (ret) { pr_err("pblk: emeta I/O submission failed: %d\n", ret); goto fail_rollback; } return NVM_IO_OK; fail_rollback: pblk_up_page(pblk, rqd->ppa_list, rqd->nr_ppas); spin_lock(&l_mg->close_lock); pblk_dealloc_page(pblk, meta_line, rq_ppas); list_add(&meta_line->list, &meta_line->list); spin_unlock(&l_mg->close_lock); fail_free_bio: bio_put(bio); fail_free_rqd: pblk_free_rqd(pblk, rqd, PBLK_WRITE_INT); return ret; } static inline bool pblk_valid_meta_ppa(struct pblk *pblk, struct pblk_line *meta_line, struct nvm_rq *data_rqd) { struct nvm_tgt_dev *dev = pblk->dev; struct nvm_geo *geo = &dev->geo; struct pblk_c_ctx *data_c_ctx = nvm_rq_to_pdu(data_rqd); struct pblk_line *data_line = pblk_line_get_data(pblk); struct ppa_addr ppa, ppa_opt; u64 paddr; int pos_opt; /* Schedule a metadata I/O that is half the distance from the data I/O * with regards to the number of LUNs forming the pblk instance. This * balances LUN conflicts across every I/O. * * When the LUN configuration changes (e.g., due to GC), this distance * can align, which would result on metadata and data I/Os colliding. In * this case, modify the distance to not be optimal, but move the * optimal in the right direction. */ paddr = pblk_lookup_page(pblk, meta_line); ppa = addr_to_gen_ppa(pblk, paddr, 0); ppa_opt = addr_to_gen_ppa(pblk, paddr + data_line->meta_distance, 0); pos_opt = pblk_ppa_to_pos(geo, ppa_opt); if (test_bit(pos_opt, data_c_ctx->lun_bitmap) || test_bit(pos_opt, data_line->blk_bitmap)) return true; if (unlikely(pblk_ppa_comp(ppa_opt, ppa))) data_line->meta_distance--; return false; } static struct pblk_line *pblk_should_submit_meta_io(struct pblk *pblk, struct nvm_rq *data_rqd) { struct pblk_line_meta *lm = &pblk->lm; struct pblk_line_mgmt *l_mg = &pblk->l_mg; struct pblk_line *meta_line; spin_lock(&l_mg->close_lock); retry: if (list_empty(&l_mg->emeta_list)) { spin_unlock(&l_mg->close_lock); return NULL; } meta_line = list_first_entry(&l_mg->emeta_list, struct pblk_line, list); if (meta_line->emeta->mem >= lm->emeta_len[0]) goto retry; spin_unlock(&l_mg->close_lock); if (!pblk_valid_meta_ppa(pblk, meta_line, data_rqd)) return NULL; return meta_line; } static int pblk_submit_io_set(struct pblk *pblk, struct nvm_rq *rqd) { struct ppa_addr erase_ppa; struct pblk_line *meta_line; int err; pblk_ppa_set_empty(&erase_ppa); /* Assign lbas to ppas and populate request structure */ err = pblk_setup_w_rq(pblk, rqd, &erase_ppa); if (err) { pr_err("pblk: could not setup write request: %d\n", err); return NVM_IO_ERR; } meta_line = pblk_should_submit_meta_io(pblk, rqd); /* Submit data write for current data line */ err = pblk_submit_io(pblk, rqd); if (err) { pr_err("pblk: data I/O submission failed: %d\n", err); return NVM_IO_ERR; } if (!pblk_ppa_empty(erase_ppa)) { /* Submit erase for next data line */ if (pblk_blk_erase_async(pblk, erase_ppa)) { struct pblk_line *e_line = pblk_line_get_erase(pblk); struct nvm_tgt_dev *dev = pblk->dev; struct nvm_geo *geo = &dev->geo; int bit; atomic_inc(&e_line->left_eblks); bit = pblk_ppa_to_pos(geo, erase_ppa); WARN_ON(!test_and_clear_bit(bit, e_line->erase_bitmap)); } } if (meta_line) { /* Submit metadata write for previous data line */ err = pblk_submit_meta_io(pblk, meta_line); if (err) { pr_err("pblk: metadata I/O submission failed: %d", err); return NVM_IO_ERR; } } return NVM_IO_OK; } static void pblk_free_write_rqd(struct pblk *pblk, struct nvm_rq *rqd) { struct pblk_c_ctx *c_ctx = nvm_rq_to_pdu(rqd); struct bio *bio = rqd->bio; if (c_ctx->nr_padded) pblk_bio_free_pages(pblk, bio, c_ctx->nr_valid, c_ctx->nr_padded); } static int pblk_submit_write(struct pblk *pblk) { struct bio *bio; struct nvm_rq *rqd; unsigned int secs_avail, secs_to_sync, secs_to_com; unsigned int secs_to_flush; unsigned long pos; /* If there are no sectors in the cache, flushes (bios without data) * will be cleared on the cache threads */ secs_avail = pblk_rb_read_count(&pblk->rwb); if (!secs_avail) return 1; secs_to_flush = pblk_rb_flush_point_count(&pblk->rwb); if (!secs_to_flush && secs_avail < pblk->min_write_pgs) return 1; secs_to_sync = pblk_calc_secs_to_sync(pblk, secs_avail, secs_to_flush); if (secs_to_sync > pblk->max_write_pgs) { pr_err("pblk: bad buffer sync calculation\n"); return 1; } secs_to_com = (secs_to_sync > secs_avail) ? secs_avail : secs_to_sync; pos = pblk_rb_read_commit(&pblk->rwb, secs_to_com); bio = bio_alloc(GFP_KERNEL, secs_to_sync); bio->bi_iter.bi_sector = 0; /* internal bio */ bio_set_op_attrs(bio, REQ_OP_WRITE, 0); rqd = pblk_alloc_rqd(pblk, PBLK_WRITE); rqd->bio = bio; if (pblk_rb_read_to_bio(&pblk->rwb, rqd, pos, secs_to_sync, secs_avail)) { pr_err("pblk: corrupted write bio\n"); goto fail_put_bio; } if (pblk_submit_io_set(pblk, rqd)) goto fail_free_bio; #ifdef CONFIG_NVM_DEBUG atomic_long_add(secs_to_sync, &pblk->sub_writes); #endif return 0; fail_free_bio: pblk_free_write_rqd(pblk, rqd); fail_put_bio: bio_put(bio); pblk_free_rqd(pblk, rqd, PBLK_WRITE); return 1; } int pblk_write_ts(void *data) { struct pblk *pblk = data; while (!kthread_should_stop()) { if (!pblk_submit_write(pblk)) continue; set_current_state(TASK_INTERRUPTIBLE); io_schedule(); } return 0; }