Adding upstream version 5.10.209.upstream/5.10.209upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 875 insertions, 0 deletions

diff --git a/drivers/lightnvm/pblk-recovery.c b/drivers/lightnvm/pblk-recovery.c
new file mode 100644
index 000000000..299ef47a1
--- /dev/null
+++ b/drivers/lightnvm/pblk-recovery.c
@@ -0,0 +1,875 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2016 CNEX Labs
+ * Initial: Javier Gonzalez <javier@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-recovery.c - pblk's recovery path
+ *
+ * The L2P recovery path is single threaded as the L2P table is updated in order
+ * following the line sequence ID.
+ */
+
+#include "pblk.h"
+#include "pblk-trace.h"
+
+int pblk_recov_check_emeta(struct pblk *pblk, struct line_emeta *emeta_buf)
+{
+	u32 crc;
+
+	crc = pblk_calc_emeta_crc(pblk, emeta_buf);
+	if (le32_to_cpu(emeta_buf->crc) != crc)
+		return 1;
+
+	if (le32_to_cpu(emeta_buf->header.identifier) != PBLK_MAGIC)
+		return 1;
+
+	return 0;
+}
+
+static int pblk_recov_l2p_from_emeta(struct pblk *pblk, struct pblk_line *line)
+{
+	struct nvm_tgt_dev *dev = pblk->dev;
+	struct nvm_geo *geo = &dev->geo;
+	struct pblk_line_meta *lm = &pblk->lm;
+	struct pblk_emeta *emeta = line->emeta;
+	struct line_emeta *emeta_buf = emeta->buf;
+	__le64 *lba_list;
+	u64 data_start, data_end;
+	u64 nr_valid_lbas, nr_lbas = 0;
+	u64 i;
+
+	lba_list = emeta_to_lbas(pblk, emeta_buf);
+	if (!lba_list)
+		return 1;
+
+	data_start = pblk_line_smeta_start(pblk, line) + lm->smeta_sec;
+	data_end = line->emeta_ssec;
+	nr_valid_lbas = le64_to_cpu(emeta_buf->nr_valid_lbas);
+
+	for (i = data_start; i < data_end; i++) {
+		struct ppa_addr ppa;
+		int pos;
+
+		ppa = addr_to_gen_ppa(pblk, i, line->id);
+		pos = pblk_ppa_to_pos(geo, ppa);
+
+		/* Do not update bad blocks */
+		if (test_bit(pos, line->blk_bitmap))
+			continue;
+
+		if (le64_to_cpu(lba_list[i]) == ADDR_EMPTY) {
+			spin_lock(&line->lock);
+			if (test_and_set_bit(i, line->invalid_bitmap))
+				WARN_ONCE(1, "pblk: rec. double invalidate:\n");
+			else
+				le32_add_cpu(line->vsc, -1);
+			spin_unlock(&line->lock);
+
+			continue;
+		}
+
+		pblk_update_map(pblk, le64_to_cpu(lba_list[i]), ppa);
+		nr_lbas++;
+	}
+
+	if (nr_valid_lbas != nr_lbas)
+		pblk_err(pblk, "line %d - inconsistent lba list(%llu/%llu)\n",
+				line->id, nr_valid_lbas, nr_lbas);
+
+	line->left_msecs = 0;
+
+	return 0;
+}
+
+static void pblk_update_line_wp(struct pblk *pblk, struct pblk_line *line,
+				u64 written_secs)
+{
+	struct pblk_line_mgmt *l_mg = &pblk->l_mg;
+	int i;
+
+	for (i = 0; i < written_secs; i += pblk->min_write_pgs)
+		__pblk_alloc_page(pblk, line, pblk->min_write_pgs);
+
+	spin_lock(&l_mg->free_lock);
+	if (written_secs > line->left_msecs) {
+		/*
+		 * We have all data sectors written
+		 * and some emeta sectors written too.
+		 */
+		line->left_msecs = 0;
+	} else {
+		/* We have only some data sectors written. */
+		line->left_msecs -= written_secs;
+	}
+	spin_unlock(&l_mg->free_lock);
+}
+
+static u64 pblk_sec_in_open_line(struct pblk *pblk, struct pblk_line *line)
+{
+	struct pblk_line_meta *lm = &pblk->lm;
+	int nr_bb = bitmap_weight(line->blk_bitmap, lm->blk_per_line);
+	u64 written_secs = 0;
+	int valid_chunks = 0;
+	int i;
+
+	for (i = 0; i < lm->blk_per_line; i++) {
+		struct nvm_chk_meta *chunk = &line->chks[i];
+
+		if (chunk->state & NVM_CHK_ST_OFFLINE)
+			continue;
+
+		written_secs += chunk->wp;
+		valid_chunks++;
+	}
+
+	if (lm->blk_per_line - nr_bb != valid_chunks)
+		pblk_err(pblk, "recovery line %d is bad\n", line->id);
+
+	pblk_update_line_wp(pblk, line, written_secs - lm->smeta_sec);
+
+	return written_secs;
+}
+
+struct pblk_recov_alloc {
+	struct ppa_addr *ppa_list;
+	void *meta_list;
+	struct nvm_rq *rqd;
+	void *data;
+	dma_addr_t dma_ppa_list;
+	dma_addr_t dma_meta_list;
+};
+
+static void pblk_recov_complete(struct kref *ref)
+{
+	struct pblk_pad_rq *pad_rq = container_of(ref, struct pblk_pad_rq, ref);
+
+	complete(&pad_rq->wait);
+}
+
+static void pblk_end_io_recov(struct nvm_rq *rqd)
+{
+	struct ppa_addr *ppa_list = nvm_rq_to_ppa_list(rqd);
+	struct pblk_pad_rq *pad_rq = rqd->private;
+	struct pblk *pblk = pad_rq->pblk;
+
+	pblk_up_chunk(pblk, ppa_list[0]);
+
+	pblk_free_rqd(pblk, rqd, PBLK_WRITE_INT);
+
+	atomic_dec(&pblk->inflight_io);
+	kref_put(&pad_rq->ref, pblk_recov_complete);
+}
+
+/* pad line using line bitmap.  */
+static int pblk_recov_pad_line(struct pblk *pblk, struct pblk_line *line,
+			       int left_ppas)
+{
+	struct nvm_tgt_dev *dev = pblk->dev;
+	struct nvm_geo *geo = &dev->geo;
+	void *meta_list;
+	struct pblk_pad_rq *pad_rq;
+	struct nvm_rq *rqd;
+	struct ppa_addr *ppa_list;
+	void *data;
+	__le64 *lba_list = emeta_to_lbas(pblk, line->emeta->buf);
+	u64 w_ptr = line->cur_sec;
+	int left_line_ppas, rq_ppas;
+	int i, j;
+	int ret = 0;
+
+	spin_lock(&line->lock);
+	left_line_ppas = line->left_msecs;
+	spin_unlock(&line->lock);
+
+	pad_rq = kmalloc(sizeof(struct pblk_pad_rq), GFP_KERNEL);
+	if (!pad_rq)
+		return -ENOMEM;
+
+	data = vzalloc(array_size(pblk->max_write_pgs, geo->csecs));
+	if (!data) {
+		ret = -ENOMEM;
+		goto free_rq;
+	}
+
+	pad_rq->pblk = pblk;
+	init_completion(&pad_rq->wait);
+	kref_init(&pad_rq->ref);
+
+next_pad_rq:
+	rq_ppas = pblk_calc_secs(pblk, left_ppas, 0, false);
+	if (rq_ppas < pblk->min_write_pgs) {
+		pblk_err(pblk, "corrupted pad line %d\n", line->id);
+		goto fail_complete;
+	}
+
+	rqd = pblk_alloc_rqd(pblk, PBLK_WRITE_INT);
+
+	ret = pblk_alloc_rqd_meta(pblk, rqd);
+	if (ret) {
+		pblk_free_rqd(pblk, rqd, PBLK_WRITE_INT);
+		goto fail_complete;
+	}
+
+	rqd->bio = NULL;
+	rqd->opcode = NVM_OP_PWRITE;
+	rqd->is_seq = 1;
+	rqd->nr_ppas = rq_ppas;
+	rqd->end_io = pblk_end_io_recov;
+	rqd->private = pad_rq;
+
+	ppa_list = nvm_rq_to_ppa_list(rqd);
+	meta_list = rqd->meta_list;
+
+	for (i = 0; i < rqd->nr_ppas; ) {
+		struct ppa_addr ppa;
+		int pos;
+
+		w_ptr = pblk_alloc_page(pblk, line, pblk->min_write_pgs);
+		ppa = addr_to_gen_ppa(pblk, w_ptr, line->id);
+		pos = pblk_ppa_to_pos(geo, ppa);
+
+		while (test_bit(pos, line->blk_bitmap)) {
+			w_ptr += pblk->min_write_pgs;
+			ppa = addr_to_gen_ppa(pblk, w_ptr, line->id);
+			pos = pblk_ppa_to_pos(geo, ppa);
+		}
+
+		for (j = 0; j < pblk->min_write_pgs; j++, i++, w_ptr++) {
+			struct ppa_addr dev_ppa;
+			struct pblk_sec_meta *meta;
+			__le64 addr_empty = cpu_to_le64(ADDR_EMPTY);
+
+			dev_ppa = addr_to_gen_ppa(pblk, w_ptr, line->id);
+
+			pblk_map_invalidate(pblk, dev_ppa);
+			lba_list[w_ptr] = addr_empty;
+			meta = pblk_get_meta(pblk, meta_list, i);
+			meta->lba = addr_empty;
+			ppa_list[i] = dev_ppa;
+		}
+	}
+
+	kref_get(&pad_rq->ref);
+	pblk_down_chunk(pblk, ppa_list[0]);
+
+	ret = pblk_submit_io(pblk, rqd, data);
+	if (ret) {
+		pblk_err(pblk, "I/O submission failed: %d\n", ret);
+		pblk_up_chunk(pblk, ppa_list[0]);
+		kref_put(&pad_rq->ref, pblk_recov_complete);
+		pblk_free_rqd(pblk, rqd, PBLK_WRITE_INT);
+		goto fail_complete;
+	}
+
+	left_line_ppas -= rq_ppas;
+	left_ppas -= rq_ppas;
+	if (left_ppas && left_line_ppas)
+		goto next_pad_rq;
+
+fail_complete:
+	kref_put(&pad_rq->ref, pblk_recov_complete);
+	wait_for_completion(&pad_rq->wait);
+
+	if (!pblk_line_is_full(line))
+		pblk_err(pblk, "corrupted padded line: %d\n", line->id);
+
+	vfree(data);
+free_rq:
+	kfree(pad_rq);
+	return ret;
+}
+
+static int pblk_pad_distance(struct pblk *pblk, struct pblk_line *line)
+{
+	struct nvm_tgt_dev *dev = pblk->dev;
+	struct nvm_geo *geo = &dev->geo;
+	int distance = geo->mw_cunits * geo->all_luns * geo->ws_opt;
+
+	return (distance > line->left_msecs) ? line->left_msecs : distance;
+}
+
+/* Return a chunk belonging to a line by stripe(write order) index */
+static struct nvm_chk_meta *pblk_get_stripe_chunk(struct pblk *pblk,
+						  struct pblk_line *line,
+						  int index)
+{
+	struct nvm_tgt_dev *dev = pblk->dev;
+	struct nvm_geo *geo = &dev->geo;
+	struct pblk_lun *rlun;
+	struct ppa_addr ppa;
+	int pos;
+
+	rlun = &pblk->luns[index];
+	ppa = rlun->bppa;
+	pos = pblk_ppa_to_pos(geo, ppa);
+
+	return &line->chks[pos];
+}
+
+static int pblk_line_wps_are_unbalanced(struct pblk *pblk,
+				      struct pblk_line *line)
+{
+	struct pblk_line_meta *lm = &pblk->lm;
+	int blk_in_line = lm->blk_per_line;
+	struct nvm_chk_meta *chunk;
+	u64 max_wp, min_wp;
+	int i;
+
+	i = find_first_zero_bit(line->blk_bitmap, blk_in_line);
+
+	/* If there is one or zero good chunks in the line,
+	 * the write pointers can't be unbalanced.
+	 */
+	if (i >= (blk_in_line - 1))
+		return 0;
+
+	chunk = pblk_get_stripe_chunk(pblk, line, i);
+	max_wp = chunk->wp;
+	if (max_wp > pblk->max_write_pgs)
+		min_wp = max_wp - pblk->max_write_pgs;
+	else
+		min_wp = 0;
+
+	i = find_next_zero_bit(line->blk_bitmap, blk_in_line, i + 1);
+	while (i < blk_in_line) {
+		chunk = pblk_get_stripe_chunk(pblk, line, i);
+		if (chunk->wp > max_wp || chunk->wp < min_wp)
+			return 1;
+
+		i = find_next_zero_bit(line->blk_bitmap, blk_in_line, i + 1);
+	}
+
+	return 0;
+}
+
+static int pblk_recov_scan_oob(struct pblk *pblk, struct pblk_line *line,
+			       struct pblk_recov_alloc p)
+{
+	struct nvm_tgt_dev *dev = pblk->dev;
+	struct pblk_line_meta *lm = &pblk->lm;
+	struct nvm_geo *geo = &dev->geo;
+	struct ppa_addr *ppa_list;
+	void *meta_list;
+	struct nvm_rq *rqd;
+	void *data;
+	dma_addr_t dma_ppa_list, dma_meta_list;
+	__le64 *lba_list;
+	u64 paddr = pblk_line_smeta_start(pblk, line) + lm->smeta_sec;
+	bool padded = false;
+	int rq_ppas;
+	int i, j;
+	int ret;
+	u64 left_ppas = pblk_sec_in_open_line(pblk, line) - lm->smeta_sec;
+
+	if (pblk_line_wps_are_unbalanced(pblk, line))
+		pblk_warn(pblk, "recovering unbalanced line (%d)\n", line->id);
+
+	ppa_list = p.ppa_list;
+	meta_list = p.meta_list;
+	rqd = p.rqd;
+	data = p.data;
+	dma_ppa_list = p.dma_ppa_list;
+	dma_meta_list = p.dma_meta_list;
+
+	lba_list = emeta_to_lbas(pblk, line->emeta->buf);
+
+next_rq:
+	memset(rqd, 0, pblk_g_rq_size);
+
+	rq_ppas = pblk_calc_secs(pblk, left_ppas, 0, false);
+	if (!rq_ppas)
+		rq_ppas = pblk->min_write_pgs;
+
+retry_rq:
+	rqd->bio = NULL;
+	rqd->opcode = NVM_OP_PREAD;
+	rqd->meta_list = meta_list;
+	rqd->nr_ppas = rq_ppas;
+	rqd->ppa_list = ppa_list;
+	rqd->dma_ppa_list = dma_ppa_list;
+	rqd->dma_meta_list = dma_meta_list;
+	ppa_list = nvm_rq_to_ppa_list(rqd);
+
+	if (pblk_io_aligned(pblk, rq_ppas))
+		rqd->is_seq = 1;
+
+	for (i = 0; i < rqd->nr_ppas; ) {
+		struct ppa_addr ppa;
+		int pos;
+
+		ppa = addr_to_gen_ppa(pblk, paddr, line->id);
+		pos = pblk_ppa_to_pos(geo, ppa);
+
+		while (test_bit(pos, line->blk_bitmap)) {
+			paddr += pblk->min_write_pgs;
+			ppa = addr_to_gen_ppa(pblk, paddr, line->id);
+			pos = pblk_ppa_to_pos(geo, ppa);
+		}
+
+		for (j = 0; j < pblk->min_write_pgs; j++, i++)
+			ppa_list[i] =
+				addr_to_gen_ppa(pblk, paddr + j, line->id);
+	}
+
+	ret = pblk_submit_io_sync(pblk, rqd, data);
+	if (ret) {
+		pblk_err(pblk, "I/O submission failed: %d\n", ret);
+		return ret;
+	}
+
+	atomic_dec(&pblk->inflight_io);
+
+	/* If a read fails, do a best effort by padding the line and retrying */
+	if (rqd->error && rqd->error != NVM_RSP_WARN_HIGHECC) {
+		int pad_distance, ret;
+
+		if (padded) {
+			pblk_log_read_err(pblk, rqd);
+			return -EINTR;
+		}
+
+		pad_distance = pblk_pad_distance(pblk, line);
+		ret = pblk_recov_pad_line(pblk, line, pad_distance);
+		if (ret) {
+			return ret;
+		}
+
+		padded = true;
+		goto retry_rq;
+	}
+
+	pblk_get_packed_meta(pblk, rqd);
+
+	for (i = 0; i < rqd->nr_ppas; i++) {
+		struct pblk_sec_meta *meta = pblk_get_meta(pblk, meta_list, i);
+		u64 lba = le64_to_cpu(meta->lba);
+
+		lba_list[paddr++] = cpu_to_le64(lba);
+
+		if (lba == ADDR_EMPTY || lba >= pblk->capacity)
+			continue;
+
+		line->nr_valid_lbas++;
+		pblk_update_map(pblk, lba, ppa_list[i]);
+	}
+
+	left_ppas -= rq_ppas;
+	if (left_ppas > 0)
+		goto next_rq;
+
+#ifdef CONFIG_NVM_PBLK_DEBUG
+	WARN_ON(padded && !pblk_line_is_full(line));
+#endif
+
+	return 0;
+}
+
+/* Scan line for lbas on out of bound area */
+static int pblk_recov_l2p_from_oob(struct pblk *pblk, struct pblk_line *line)
+{
+	struct nvm_tgt_dev *dev = pblk->dev;
+	struct nvm_geo *geo = &dev->geo;
+	struct nvm_rq *rqd;
+	struct ppa_addr *ppa_list;
+	void *meta_list;
+	struct pblk_recov_alloc p;
+	void *data;
+	dma_addr_t dma_ppa_list, dma_meta_list;
+	int ret = 0;
+
+	meta_list = nvm_dev_dma_alloc(dev->parent, GFP_KERNEL, &dma_meta_list);
+	if (!meta_list)
+		return -ENOMEM;
+
+	ppa_list = (void *)(meta_list) + pblk_dma_meta_size(pblk);
+	dma_ppa_list = dma_meta_list + pblk_dma_meta_size(pblk);
+
+	data = kcalloc(pblk->max_write_pgs, geo->csecs, GFP_KERNEL);
+	if (!data) {
+		ret = -ENOMEM;
+		goto free_meta_list;
+	}
+
+	rqd = mempool_alloc(&pblk->r_rq_pool, GFP_KERNEL);
+	memset(rqd, 0, pblk_g_rq_size);
+
+	p.ppa_list = ppa_list;
+	p.meta_list = meta_list;
+	p.rqd = rqd;
+	p.data = data;
+	p.dma_ppa_list = dma_ppa_list;
+	p.dma_meta_list = dma_meta_list;
+
+	ret = pblk_recov_scan_oob(pblk, line, p);
+	if (ret) {
+		pblk_err(pblk, "could not recover L2P form OOB\n");
+		goto out;
+	}
+
+	if (pblk_line_is_full(line))
+		pblk_line_recov_close(pblk, line);
+
+out:
+	mempool_free(rqd, &pblk->r_rq_pool);
+	kfree(data);
+free_meta_list:
+	nvm_dev_dma_free(dev->parent, meta_list, dma_meta_list);
+
+	return ret;
+}
+
+/* Insert lines ordered by sequence number (seq_num) on list */
+static void pblk_recov_line_add_ordered(struct list_head *head,
+					struct pblk_line *line)
+{
+	struct pblk_line *t = NULL;
+
+	list_for_each_entry(t, head, list)
+		if (t->seq_nr > line->seq_nr)
+			break;
+
+	__list_add(&line->list, t->list.prev, &t->list);
+}
+
+static u64 pblk_line_emeta_start(struct pblk *pblk, struct pblk_line *line)
+{
+	struct nvm_tgt_dev *dev = pblk->dev;
+	struct nvm_geo *geo = &dev->geo;
+	struct pblk_line_meta *lm = &pblk->lm;
+	unsigned int emeta_secs;
+	u64 emeta_start;
+	struct ppa_addr ppa;
+	int pos;
+
+	emeta_secs = lm->emeta_sec[0];
+	emeta_start = lm->sec_per_line;
+
+	while (emeta_secs) {
+		emeta_start--;
+		ppa = addr_to_gen_ppa(pblk, emeta_start, line->id);
+		pos = pblk_ppa_to_pos(geo, ppa);
+		if (!test_bit(pos, line->blk_bitmap))
+			emeta_secs--;
+	}
+
+	return emeta_start;
+}
+
+static int pblk_recov_check_line_version(struct pblk *pblk,
+					 struct line_emeta *emeta)
+{
+	struct line_header *header = &emeta->header;
+
+	if (header->version_major != EMETA_VERSION_MAJOR) {
+		pblk_err(pblk, "line major version mismatch: %d, expected: %d\n",
+			 header->version_major, EMETA_VERSION_MAJOR);
+		return 1;
+	}
+
+#ifdef CONFIG_NVM_PBLK_DEBUG
+	if (header->version_minor > EMETA_VERSION_MINOR)
+		pblk_info(pblk, "newer line minor version found: %d\n",
+				header->version_minor);
+#endif
+
+	return 0;
+}
+
+static void pblk_recov_wa_counters(struct pblk *pblk,
+				   struct line_emeta *emeta)
+{
+	struct pblk_line_meta *lm = &pblk->lm;
+	struct line_header *header = &emeta->header;
+	struct wa_counters *wa = emeta_to_wa(lm, emeta);
+
+	/* WA counters were introduced in emeta version 0.2 */
+	if (header->version_major > 0 || header->version_minor >= 2) {
+		u64 user = le64_to_cpu(wa->user);
+		u64 pad = le64_to_cpu(wa->pad);
+		u64 gc = le64_to_cpu(wa->gc);
+
+		atomic64_set(&pblk->user_wa, user);
+		atomic64_set(&pblk->pad_wa, pad);
+		atomic64_set(&pblk->gc_wa, gc);
+
+		pblk->user_rst_wa = user;
+		pblk->pad_rst_wa = pad;
+		pblk->gc_rst_wa = gc;
+	}
+}
+
+static int pblk_line_was_written(struct pblk_line *line,
+				 struct pblk *pblk)
+{
+
+	struct pblk_line_meta *lm = &pblk->lm;
+	struct nvm_tgt_dev *dev = pblk->dev;
+	struct nvm_geo *geo = &dev->geo;
+	struct nvm_chk_meta *chunk;
+	struct ppa_addr bppa;
+	int smeta_blk;
+
+	if (line->state == PBLK_LINESTATE_BAD)
+		return 0;
+
+	smeta_blk = find_first_zero_bit(line->blk_bitmap, lm->blk_per_line);
+	if (smeta_blk >= lm->blk_per_line)
+		return 0;
+
+	bppa = pblk->luns[smeta_blk].bppa;
+	chunk = &line->chks[pblk_ppa_to_pos(geo, bppa)];
+
+	if (chunk->state & NVM_CHK_ST_CLOSED ||
+	    (chunk->state & NVM_CHK_ST_OPEN
+	     && chunk->wp >= lm->smeta_sec))
+		return 1;
+
+	return 0;
+}
+
+static bool pblk_line_is_open(struct pblk *pblk, struct pblk_line *line)
+{
+	struct pblk_line_meta *lm = &pblk->lm;
+	int i;
+
+	for (i = 0; i < lm->blk_per_line; i++)
+		if (line->chks[i].state & NVM_CHK_ST_OPEN)
+			return true;
+
+	return false;
+}
+
+struct pblk_line *pblk_recov_l2p(struct pblk *pblk)
+{
+	struct pblk_line_meta *lm = &pblk->lm;
+	struct pblk_line_mgmt *l_mg = &pblk->l_mg;
+	struct pblk_line *line, *tline, *data_line = NULL;
+	struct pblk_smeta *smeta;
+	struct pblk_emeta *emeta;
+	struct line_smeta *smeta_buf;
+	int found_lines = 0, recovered_lines = 0, open_lines = 0;
+	int is_next = 0;
+	int meta_line;
+	int i, valid_uuid = 0;
+	LIST_HEAD(recov_list);
+
+	/* TODO: Implement FTL snapshot */
+
+	/* Scan recovery - takes place when FTL snapshot fails */
+	spin_lock(&l_mg->free_lock);
+	meta_line = find_first_zero_bit(&l_mg->meta_bitmap, PBLK_DATA_LINES);
+	set_bit(meta_line, &l_mg->meta_bitmap);
+	smeta = l_mg->sline_meta[meta_line];
+	emeta = l_mg->eline_meta[meta_line];
+	smeta_buf = (struct line_smeta *)smeta;
+	spin_unlock(&l_mg->free_lock);
+
+	/* Order data lines using their sequence number */
+	for (i = 0; i < l_mg->nr_lines; i++) {
+		u32 crc;
+
+		line = &pblk->lines[i];
+
+		memset(smeta, 0, lm->smeta_len);
+		line->smeta = smeta;
+		line->lun_bitmap = ((void *)(smeta_buf)) +
+						sizeof(struct line_smeta);
+
+		if (!pblk_line_was_written(line, pblk))
+			continue;
+
+		/* Lines that cannot be read are assumed as not written here */
+		if (pblk_line_smeta_read(pblk, line))
+			continue;
+
+		crc = pblk_calc_smeta_crc(pblk, smeta_buf);
+		if (le32_to_cpu(smeta_buf->crc) != crc)
+			continue;
+
+		if (le32_to_cpu(smeta_buf->header.identifier) != PBLK_MAGIC)
+			continue;
+
+		if (smeta_buf->header.version_major != SMETA_VERSION_MAJOR) {
+			pblk_err(pblk, "found incompatible line version %u\n",
+					smeta_buf->header.version_major);
+			return ERR_PTR(-EINVAL);
+		}
+
+		/* The first valid instance uuid is used for initialization */
+		if (!valid_uuid) {
+			guid_copy(&pblk->instance_uuid,
+				  (guid_t *)&smeta_buf->header.uuid);
+			valid_uuid = 1;
+		}
+
+		if (!guid_equal(&pblk->instance_uuid,
+				(guid_t *)&smeta_buf->header.uuid)) {
+			pblk_debug(pblk, "ignore line %u due to uuid mismatch\n",
+					i);
+			continue;
+		}
+
+		/* Update line metadata */
+		spin_lock(&line->lock);
+		line->id = le32_to_cpu(smeta_buf->header.id);
+		line->type = le16_to_cpu(smeta_buf->header.type);
+		line->seq_nr = le64_to_cpu(smeta_buf->seq_nr);
+		spin_unlock(&line->lock);
+
+		/* Update general metadata */
+		spin_lock(&l_mg->free_lock);
+		if (line->seq_nr >= l_mg->d_seq_nr)
+			l_mg->d_seq_nr = line->seq_nr + 1;
+		l_mg->nr_free_lines--;
+		spin_unlock(&l_mg->free_lock);
+
+		if (pblk_line_recov_alloc(pblk, line))
+			goto out;
+
+		pblk_recov_line_add_ordered(&recov_list, line);
+		found_lines++;
+		pblk_debug(pblk, "recovering data line %d, seq:%llu\n",
+						line->id, smeta_buf->seq_nr);
+	}
+
+	if (!found_lines) {
+		guid_gen(&pblk->instance_uuid);
+
+		spin_lock(&l_mg->free_lock);
+		WARN_ON_ONCE(!test_and_clear_bit(meta_line,
+							&l_mg->meta_bitmap));
+		spin_unlock(&l_mg->free_lock);
+
+		goto out;
+	}
+
+	/* Verify closed blocks and recover this portion of L2P table*/
+	list_for_each_entry_safe(line, tline, &recov_list, list) {
+		recovered_lines++;
+
+		line->emeta_ssec = pblk_line_emeta_start(pblk, line);
+		line->emeta = emeta;
+		memset(line->emeta->buf, 0, lm->emeta_len[0]);
+
+		if (pblk_line_is_open(pblk, line)) {
+			pblk_recov_l2p_from_oob(pblk, line);
+			goto next;
+		}
+
+		if (pblk_line_emeta_read(pblk, line, line->emeta->buf)) {
+			pblk_recov_l2p_from_oob(pblk, line);
+			goto next;
+		}
+
+		if (pblk_recov_check_emeta(pblk, line->emeta->buf)) {
+			pblk_recov_l2p_from_oob(pblk, line);
+			goto next;
+		}
+
+		if (pblk_recov_check_line_version(pblk, line->emeta->buf))
+			return ERR_PTR(-EINVAL);
+
+		pblk_recov_wa_counters(pblk, line->emeta->buf);
+
+		if (pblk_recov_l2p_from_emeta(pblk, line))
+			pblk_recov_l2p_from_oob(pblk, line);
+
+next:
+		if (pblk_line_is_full(line)) {
+			struct list_head *move_list;
+
+			spin_lock(&line->lock);
+			line->state = PBLK_LINESTATE_CLOSED;
+			trace_pblk_line_state(pblk_disk_name(pblk), line->id,
+					line->state);
+			move_list = pblk_line_gc_list(pblk, line);
+			spin_unlock(&line->lock);
+
+			spin_lock(&l_mg->gc_lock);
+			list_move_tail(&line->list, move_list);
+			spin_unlock(&l_mg->gc_lock);
+
+			mempool_free(line->map_bitmap, l_mg->bitmap_pool);
+			line->map_bitmap = NULL;
+			line->smeta = NULL;
+			line->emeta = NULL;
+		} else {
+			spin_lock(&line->lock);
+			line->state = PBLK_LINESTATE_OPEN;
+			spin_unlock(&line->lock);
+
+			line->emeta->mem = 0;
+			atomic_set(&line->emeta->sync, 0);
+
+			trace_pblk_line_state(pblk_disk_name(pblk), line->id,
+					line->state);
+
+			data_line = line;
+			line->meta_line = meta_line;
+
+			open_lines++;
+		}
+	}
+
+	if (!open_lines) {
+		spin_lock(&l_mg->free_lock);
+		WARN_ON_ONCE(!test_and_clear_bit(meta_line,
+							&l_mg->meta_bitmap));
+		spin_unlock(&l_mg->free_lock);
+	} else {
+		spin_lock(&l_mg->free_lock);
+		l_mg->data_line = data_line;
+		/* Allocate next line for preparation */
+		l_mg->data_next = pblk_line_get(pblk);
+		if (l_mg->data_next) {
+			l_mg->data_next->seq_nr = l_mg->d_seq_nr++;
+			l_mg->data_next->type = PBLK_LINETYPE_DATA;
+			is_next = 1;
+		}
+		spin_unlock(&l_mg->free_lock);
+	}
+
+	if (is_next)
+		pblk_line_erase(pblk, l_mg->data_next);
+
+out:
+	if (found_lines != recovered_lines)
+		pblk_err(pblk, "failed to recover all found lines %d/%d\n",
+						found_lines, recovered_lines);
+
+	return data_line;
+}
+
+/*
+ * Pad current line
+ */
+int pblk_recov_pad(struct pblk *pblk)
+{
+	struct pblk_line *line;
+	struct pblk_line_mgmt *l_mg = &pblk->l_mg;
+	int left_msecs;
+	int ret = 0;
+
+	spin_lock(&l_mg->free_lock);
+	line = l_mg->data_line;
+	left_msecs = line->left_msecs;
+	spin_unlock(&l_mg->free_lock);
+
+	ret = pblk_recov_pad_line(pblk, line, left_msecs);
+	if (ret) {
+		pblk_err(pblk, "tear down padding failed (%d)\n", ret);
+		return ret;
+	}
+
+	pblk_line_close_meta(pblk, line);
+	return ret;
+}