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;
+	}
+}