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-rw-r--r--drivers/lightnvm/pblk-map.c136
1 files changed, 136 insertions, 0 deletions
diff --git a/drivers/lightnvm/pblk-map.c b/drivers/lightnvm/pblk-map.c
new file mode 100644
index 000000000000..17c16955284d
--- /dev/null
+++ b/drivers/lightnvm/pblk-map.c
@@ -0,0 +1,136 @@
+/*
+ * 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-map.c - pblk's lba-ppa mapping strategy
+ *
+ */
+
+#include "pblk.h"
+
+static void pblk_map_page_data(struct pblk *pblk, unsigned int sentry,
+ struct ppa_addr *ppa_list,
+ unsigned long *lun_bitmap,
+ struct pblk_sec_meta *meta_list,
+ unsigned int valid_secs)
+{
+ struct pblk_line *line = pblk_line_get_data(pblk);
+ struct line_emeta *emeta = line->emeta;
+ struct pblk_w_ctx *w_ctx;
+ __le64 *lba_list = pblk_line_emeta_to_lbas(emeta);
+ u64 paddr;
+ int nr_secs = pblk->min_write_pgs;
+ int i;
+
+ paddr = pblk_alloc_page(pblk, line, nr_secs);
+
+ for (i = 0; i < nr_secs; i++, paddr++) {
+ /* ppa to be sent to the device */
+ ppa_list[i] = addr_to_gen_ppa(pblk, paddr, line->id);
+
+ /* Write context for target bio completion on write buffer. Note
+ * that the write buffer is protected by the sync backpointer,
+ * and a single writer thread have access to each specific entry
+ * at a time. Thus, it is safe to modify the context for the
+ * entry we are setting up for submission without taking any
+ * lock or memory barrier.
+ */
+ if (i < valid_secs) {
+ kref_get(&line->ref);
+ w_ctx = pblk_rb_w_ctx(&pblk->rwb, sentry + i);
+ w_ctx->ppa = ppa_list[i];
+ meta_list[i].lba = cpu_to_le64(w_ctx->lba);
+ lba_list[paddr] = cpu_to_le64(w_ctx->lba);
+ le64_add_cpu(&line->emeta->nr_valid_lbas, 1);
+ } else {
+ meta_list[i].lba = cpu_to_le64(ADDR_EMPTY);
+ lba_list[paddr] = cpu_to_le64(ADDR_EMPTY);
+ pblk_map_pad_invalidate(pblk, line, paddr);
+ }
+ }
+
+ if (pblk_line_is_full(line)) {
+ line = pblk_line_replace_data(pblk);
+ if (!line)
+ return;
+ }
+
+ pblk_down_rq(pblk, ppa_list, nr_secs, lun_bitmap);
+}
+
+void pblk_map_rq(struct pblk *pblk, struct nvm_rq *rqd, unsigned int sentry,
+ unsigned long *lun_bitmap, unsigned int valid_secs,
+ unsigned int off)
+{
+ struct pblk_sec_meta *meta_list = rqd->meta_list;
+ unsigned int map_secs;
+ int min = pblk->min_write_pgs;
+ int i;
+
+ for (i = off; i < rqd->nr_ppas; i += min) {
+ map_secs = (i + min > valid_secs) ? (valid_secs % min) : min;
+ pblk_map_page_data(pblk, sentry + i, &rqd->ppa_list[i],
+ lun_bitmap, &meta_list[i], map_secs);
+ }
+}
+
+/* only if erase_ppa is set, acquire erase semaphore */
+void pblk_map_erase_rq(struct pblk *pblk, struct nvm_rq *rqd,
+ unsigned int sentry, unsigned long *lun_bitmap,
+ unsigned int valid_secs, struct ppa_addr *erase_ppa)
+{
+ struct nvm_tgt_dev *dev = pblk->dev;
+ struct nvm_geo *geo = &dev->geo;
+ struct pblk_line *e_line = pblk_line_get_data_next(pblk);
+ struct pblk_sec_meta *meta_list = rqd->meta_list;
+ unsigned int map_secs;
+ int min = pblk->min_write_pgs;
+ int i, erase_lun;
+
+ for (i = 0; i < rqd->nr_ppas; i += min) {
+ map_secs = (i + min > valid_secs) ? (valid_secs % min) : min;
+ pblk_map_page_data(pblk, sentry + i, &rqd->ppa_list[i],
+ lun_bitmap, &meta_list[i], map_secs);
+
+ erase_lun = rqd->ppa_list[i].g.lun * geo->nr_chnls +
+ rqd->ppa_list[i].g.ch;
+
+ if (!test_bit(erase_lun, e_line->erase_bitmap)) {
+ if (down_trylock(&pblk->erase_sem))
+ continue;
+
+ set_bit(erase_lun, e_line->erase_bitmap);
+ atomic_dec(&e_line->left_eblks);
+ *erase_ppa = rqd->ppa_list[i];
+ erase_ppa->g.blk = e_line->id;
+
+ /* Avoid evaluating e_line->left_eblks */
+ return pblk_map_rq(pblk, rqd, sentry, lun_bitmap,
+ valid_secs, i + min);
+ }
+ }
+
+ /* Erase blocks that are bad in this line but might not be in next */
+ if (unlikely(ppa_empty(*erase_ppa))) {
+ struct pblk_line_meta *lm = &pblk->lm;
+
+ i = find_first_zero_bit(e_line->erase_bitmap, lm->blk_per_line);
+ if (i == lm->blk_per_line)
+ return;
+
+ set_bit(i, e_line->erase_bitmap);
+ atomic_dec(&e_line->left_eblks);
+ *erase_ppa = pblk->luns[i].bppa; /* set ch and lun */
+ erase_ppa->g.blk = e_line->id;
+ }
+}