v4.19.13 snapshot.
diff --git a/drivers/lightnvm/pblk-write.c b/drivers/lightnvm/pblk-write.c
new file mode 100644
index 0000000..879227d
--- /dev/null
+++ b/drivers/lightnvm/pblk-write.c
@@ -0,0 +1,671 @@
+/*
+ * 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;
+ struct pblk_rb *rwb = &pblk->rwb;
+ unsigned long ret;
+ int i;
+
+ for (i = 0; i < c_ctx->nr_valid; i++) {
+ struct pblk_w_ctx *w_ctx;
+ int pos = c_ctx->sentry + i;
+ int flags;
+
+ w_ctx = pblk_rb_w_ctx(rwb, pos);
+ flags = READ_ONCE(w_ctx->flags);
+
+ if (flags & PBLK_FLUSH_ENTRY) {
+ flags &= ~PBLK_FLUSH_ENTRY;
+ /* Release flags on context. Protect from writes */
+ smp_store_release(&w_ctx->flags, flags);
+
+#ifdef CONFIG_NVM_PBLK_DEBUG
+ atomic_dec(&rwb->inflight_flush_point);
+#endif
+ }
+
+ 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_PBLK_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_PBLK_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);
+}
+
+/* Map remaining sectors in chunk, starting from ppa */
+static void pblk_map_remaining(struct pblk *pblk, struct ppa_addr *ppa)
+{
+ struct nvm_tgt_dev *dev = pblk->dev;
+ struct nvm_geo *geo = &dev->geo;
+ struct pblk_line *line;
+ struct ppa_addr map_ppa = *ppa;
+ u64 paddr;
+ int done = 0;
+
+ line = &pblk->lines[pblk_ppa_to_line(*ppa)];
+ spin_lock(&line->lock);
+
+ while (!done) {
+ paddr = pblk_dev_ppa_to_line_addr(pblk, map_ppa);
+
+ if (!test_and_set_bit(paddr, line->map_bitmap))
+ line->left_msecs--;
+
+ if (!test_and_set_bit(paddr, line->invalid_bitmap))
+ le32_add_cpu(line->vsc, -1);
+
+ if (geo->version == NVM_OCSSD_SPEC_12) {
+ map_ppa.ppa++;
+ if (map_ppa.g.pg == geo->num_pg)
+ done = 1;
+ } else {
+ map_ppa.m.sec++;
+ if (map_ppa.m.sec == geo->clba)
+ done = 1;
+ }
+ }
+
+ line->w_err_gc->has_write_err = 1;
+ spin_unlock(&line->lock);
+}
+
+static void pblk_prepare_resubmit(struct pblk *pblk, unsigned int sentry,
+ unsigned int nr_entries)
+{
+ struct pblk_rb *rb = &pblk->rwb;
+ struct pblk_rb_entry *entry;
+ struct pblk_line *line;
+ struct pblk_w_ctx *w_ctx;
+ struct ppa_addr ppa_l2p;
+ int flags;
+ unsigned int pos, i;
+
+ spin_lock(&pblk->trans_lock);
+ pos = sentry;
+ for (i = 0; i < nr_entries; i++) {
+ entry = &rb->entries[pos];
+ w_ctx = &entry->w_ctx;
+
+ /* Check if the lba has been overwritten */
+ ppa_l2p = pblk_trans_map_get(pblk, w_ctx->lba);
+ if (!pblk_ppa_comp(ppa_l2p, entry->cacheline))
+ w_ctx->lba = ADDR_EMPTY;
+
+ /* Mark up the entry as submittable again */
+ flags = READ_ONCE(w_ctx->flags);
+ flags |= PBLK_WRITTEN_DATA;
+ /* Release flags on write context. Protect from writes */
+ smp_store_release(&w_ctx->flags, flags);
+
+ /* Decrese the reference count to the line as we will
+ * re-map these entries
+ */
+ line = &pblk->lines[pblk_ppa_to_line(w_ctx->ppa)];
+ kref_put(&line->ref, pblk_line_put);
+
+ pos = (pos + 1) & (rb->nr_entries - 1);
+ }
+ spin_unlock(&pblk->trans_lock);
+}
+
+static void pblk_queue_resubmit(struct pblk *pblk, struct pblk_c_ctx *c_ctx)
+{
+ struct pblk_c_ctx *r_ctx;
+
+ r_ctx = kzalloc(sizeof(struct pblk_c_ctx), GFP_KERNEL);
+ if (!r_ctx)
+ return;
+
+ r_ctx->lun_bitmap = NULL;
+ r_ctx->sentry = c_ctx->sentry;
+ r_ctx->nr_valid = c_ctx->nr_valid;
+ r_ctx->nr_padded = c_ctx->nr_padded;
+
+ spin_lock(&pblk->resubmit_lock);
+ list_add_tail(&r_ctx->list, &pblk->resubmit_list);
+ spin_unlock(&pblk->resubmit_lock);
+
+#ifdef CONFIG_NVM_PBLK_DEBUG
+ atomic_long_add(c_ctx->nr_valid, &pblk->recov_writes);
+#endif
+}
+
+static void pblk_submit_rec(struct work_struct *work)
+{
+ struct pblk_rec_ctx *recovery =
+ container_of(work, struct pblk_rec_ctx, ws_rec);
+ struct pblk *pblk = recovery->pblk;
+ struct nvm_rq *rqd = recovery->rqd;
+ struct pblk_c_ctx *c_ctx = nvm_rq_to_pdu(rqd);
+ struct ppa_addr *ppa_list;
+
+ pblk_log_write_err(pblk, rqd);
+
+ if (rqd->nr_ppas == 1)
+ ppa_list = &rqd->ppa_addr;
+ else
+ ppa_list = rqd->ppa_list;
+
+ pblk_map_remaining(pblk, ppa_list);
+ pblk_queue_resubmit(pblk, c_ctx);
+
+ pblk_up_rq(pblk, rqd->ppa_list, rqd->nr_ppas, c_ctx->lun_bitmap);
+ if (c_ctx->nr_padded)
+ pblk_bio_free_pages(pblk, rqd->bio, c_ctx->nr_valid,
+ c_ctx->nr_padded);
+ bio_put(rqd->bio);
+ pblk_free_rqd(pblk, rqd, PBLK_WRITE);
+ mempool_free(recovery, &pblk->rec_pool);
+
+ atomic_dec(&pblk->inflight_io);
+}
+
+
+static void pblk_end_w_fail(struct pblk *pblk, struct nvm_rq *rqd)
+{
+ struct pblk_rec_ctx *recovery;
+
+ recovery = mempool_alloc(&pblk->rec_pool, GFP_ATOMIC);
+ if (!recovery) {
+ pblk_err(pblk, "could not allocate recovery work\n");
+ return;
+ }
+
+ recovery->pblk = pblk;
+ recovery->rqd = rqd;
+
+ INIT_WORK(&recovery->ws_rec, pblk_submit_rec);
+ queue_work(pblk->close_wq, &recovery->ws_rec);
+}
+
+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_end_w_fail(pblk, rqd);
+ return;
+ }
+#ifdef CONFIG_NVM_PBLK_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);
+ pblk_err(pblk, "metadata I/O failed. Line %d\n", line->id);
+ line->w_err_gc->has_write_err = 1;
+ }
+
+ 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;
+}
+
+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_PBLK_DEBUG
+ if ((!secs_to_sync && secs_to_flush)
+ || (secs_to_sync < 0)
+ || (secs_to_sync > secs_avail && !secs_to_flush)) {
+ pblk_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->csecs;
+ 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)) {
+ pblk_err(pblk, "failed to map emeta io");
+ 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);
+ }
+
+ spin_lock(&l_mg->close_lock);
+ emeta->mem += rq_len;
+ if (emeta->mem >= lm->emeta_len[0])
+ 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) {
+ pblk_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);
+ 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]) {
+ spin_unlock(&l_mg->close_lock);
+ return NULL;
+ }
+ 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) {
+ pblk_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) {
+ pblk_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) {
+ pblk_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;
+ unsigned int resubmit;
+
+ spin_lock(&pblk->resubmit_lock);
+ resubmit = !list_empty(&pblk->resubmit_list);
+ spin_unlock(&pblk->resubmit_lock);
+
+ /* Resubmit failed writes first */
+ if (resubmit) {
+ struct pblk_c_ctx *r_ctx;
+
+ spin_lock(&pblk->resubmit_lock);
+ r_ctx = list_first_entry(&pblk->resubmit_list,
+ struct pblk_c_ctx, list);
+ list_del(&r_ctx->list);
+ spin_unlock(&pblk->resubmit_lock);
+
+ secs_avail = r_ctx->nr_valid;
+ pos = r_ctx->sentry;
+
+ pblk_prepare_resubmit(pblk, pos, secs_avail);
+ secs_to_sync = pblk_calc_secs_to_sync(pblk, secs_avail,
+ secs_avail);
+
+ kfree(r_ctx);
+ } else {
+ /* 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) {
+ pblk_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)) {
+ pblk_err(pblk, "corrupted write bio\n");
+ goto fail_put_bio;
+ }
+
+ if (pblk_submit_io_set(pblk, rqd))
+ goto fail_free_bio;
+
+#ifdef CONFIG_NVM_PBLK_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;
+}