[PATCH 0/2] lightnvm: patches for 4.15 on core

[PATCH 0/2] lightnvm: patches for 4.15 on core

[Javier González]

These are 2 patches on the subsystem for 4.15.

The first one is a fix on the passtrhough path that enables fail fast,
just as it is done on standard nvme passtrough commands.

The second one implements a generic way to send sync. I/O from targets.
Trough time, we ended up having _many_ wait_for_completion()
constructions to implement sync. I/O, both on pblk and at the subsystem
level. One of the main issues - besides code replication - is that we
could not benefit from improvements on blk_execute_rq to prevent hangs.
This should fix it.

Javier González (2):
  lightnvm: fail fast on passthrough commands
  lightnvm: implement generic path for sync I/O

 drivers/lightnvm/core.c          | 25 ++++++++-----
 drivers/lightnvm/pblk-core.c     | 78 +++++++++++++---------------------------
 drivers/lightnvm/pblk-read.c     | 21 ++---------
 drivers/lightnvm/pblk-recovery.c | 31 ++--------------
 drivers/lightnvm/pblk.h          | 42 ++++++++++++++++++++--
 drivers/nvme/host/lightnvm.c     | 72 ++++++++++++++++++++++++++++---------
 include/linux/lightnvm.h         |  3 ++
 7 files changed, 145 insertions(+), 127 deletions(-)

-- 
2.7.4

[PATCH 1/2] lightnvm: fail fast on passthrough commands

[Javier González]

Make LightNVM passhtrough commands fail fast. User space will then take
care of re-submitting.

Fixes: 84d4add793c6 ('lightnvm: add ioctls for vector I/Os')
Signed-off-by: Javier González <javier@cnexlabs.com>
---
 drivers/nvme/host/lightnvm.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/drivers/nvme/host/lightnvm.c b/drivers/nvme/host/lightnvm.c
index 1f79e3f141e6..6017153c2439 100644
--- a/drivers/nvme/host/lightnvm.c
+++ b/drivers/nvme/host/lightnvm.c
@@ -600,8 +600,6 @@ static int nvme_nvm_submit_user_cmd(struct request_queue *q,
 
 	rq->timeout = timeout ? timeout : ADMIN_TIMEOUT;
 
-	rq->cmd_flags &= ~REQ_FAILFAST_DRIVER;
-
 	if (ppa_buf && ppa_len) {
 		ppa_list = dma_pool_alloc(dev->dma_pool, GFP_KERNEL, &ppa_dma);
 		if (!ppa_list) {
-- 
2.7.4

[PATCH 2/2] lightnvm: implement generic path for sync I/O

[Javier González]

Implement a generic path for sending sync I/O on LightNVM. This allows
to reuse the standard synchronous path trough blk_execute_rq(), instead
of implementing a wait_for_completion on the target side (e.g., pblk).

Signed-off-by: Javier González <javier@cnexlabs.com>
---
 drivers/lightnvm/core.c          | 25 ++++++++-----
 drivers/lightnvm/pblk-core.c     | 78 +++++++++++++---------------------------
 drivers/lightnvm/pblk-read.c     | 21 ++---------
 drivers/lightnvm/pblk-recovery.c | 31 ++--------------
 drivers/lightnvm/pblk.h          | 42 ++++++++++++++++++++--
 drivers/nvme/host/lightnvm.c     | 70 ++++++++++++++++++++++++++++--------
 include/linux/lightnvm.h         |  3 ++
 7 files changed, 145 insertions(+), 125 deletions(-)

diff --git a/drivers/lightnvm/core.c b/drivers/lightnvm/core.c
index 0e5f77234c79..fe21f4dd33e9 100644
--- a/drivers/lightnvm/core.c
+++ b/drivers/lightnvm/core.c
@@ -720,12 +720,25 @@ int nvm_submit_io(struct nvm_tgt_dev *tgt_dev, struct nvm_rq *rqd)
 }
 EXPORT_SYMBOL(nvm_submit_io);
 
-static void nvm_end_io_sync(struct nvm_rq *rqd)
+int nvm_submit_io_sync(struct nvm_tgt_dev *tgt_dev, struct nvm_rq *rqd)
 {
-	struct completion *waiting = rqd->private;
+	struct nvm_dev *dev = tgt_dev->parent;
+	int ret;
 
-	complete(waiting);
+	if (!dev->ops->submit_io_sync)
+		return -ENODEV;
+
+	nvm_rq_tgt_to_dev(tgt_dev, rqd);
+
+	rqd->dev = tgt_dev;
+
+	/* In case of error, fail with right address format */
+	ret = dev->ops->submit_io_sync(dev, rqd);
+	nvm_rq_dev_to_tgt(tgt_dev, rqd);
+
+	return ret;
 }
+EXPORT_SYMBOL(nvm_submit_io_sync);
 
 int nvm_erase_sync(struct nvm_tgt_dev *tgt_dev, struct ppa_addr *ppas,
 								int nr_ppas)
@@ -733,25 +746,21 @@ int nvm_erase_sync(struct nvm_tgt_dev *tgt_dev, struct ppa_addr *ppas,
 	struct nvm_geo *geo = &tgt_dev->geo;
 	struct nvm_rq rqd;
 	int ret;
-	DECLARE_COMPLETION_ONSTACK(wait);
 
 	memset(&rqd, 0, sizeof(struct nvm_rq));
 
 	rqd.opcode = NVM_OP_ERASE;
-	rqd.end_io = nvm_end_io_sync;
-	rqd.private = &wait;
 	rqd.flags = geo->plane_mode >> 1;
 
 	ret = nvm_set_rqd_ppalist(tgt_dev, &rqd, ppas, nr_ppas);
 	if (ret)
 		return ret;
 
-	ret = nvm_submit_io(tgt_dev, &rqd);
+	ret = nvm_submit_io_sync(tgt_dev, &rqd);
 	if (ret) {
 		pr_err("rrpr: erase I/O submission failed: %d\n", ret);
 		goto free_ppa_list;
 	}
-	wait_for_completion_io(&wait);
 
 free_ppa_list:
 	nvm_free_rqd_ppalist(tgt_dev, &rqd);
diff --git a/drivers/lightnvm/pblk-core.c b/drivers/lightnvm/pblk-core.c
index 4199119a0754..ce90213a42fa 100644
--- a/drivers/lightnvm/pblk-core.c
+++ b/drivers/lightnvm/pblk-core.c
@@ -412,34 +412,11 @@ int pblk_submit_io(struct pblk *pblk, struct nvm_rq *rqd)
 	struct nvm_tgt_dev *dev = pblk->dev;
 
 #ifdef CONFIG_NVM_DEBUG
-	struct ppa_addr *ppa_list;
+	int ret;
 
-	ppa_list = (rqd->nr_ppas > 1) ? rqd->ppa_list : &rqd->ppa_addr;
-	if (pblk_boundary_ppa_checks(dev, ppa_list, rqd->nr_ppas)) {
-		WARN_ON(1);
-		return -EINVAL;
-	}
-
-	if (rqd->opcode == NVM_OP_PWRITE) {
-		struct pblk_line *line;
-		struct ppa_addr ppa;
-		int i;
-
-		for (i = 0; i < rqd->nr_ppas; i++) {
-			ppa = ppa_list[i];
-			line = &pblk->lines[pblk_dev_ppa_to_line(ppa)];
-
-			spin_lock(&line->lock);
-			if (line->state != PBLK_LINESTATE_OPEN) {
-				pr_err("pblk: bad ppa: line:%d,state:%d\n",
-							line->id, line->state);
-				WARN_ON(1);
-				spin_unlock(&line->lock);
-				return -EINVAL;
-			}
-			spin_unlock(&line->lock);
-		}
-	}
+	ret = pblk_check_io(pblk, rqd);
+	if (ret)
+		return ret;
 #endif
 
 	atomic_inc(&pblk->inflight_io);
@@ -447,6 +424,23 @@ int pblk_submit_io(struct pblk *pblk, struct nvm_rq *rqd)
 	return nvm_submit_io(dev, rqd);
 }
 
+int pblk_submit_io_sync(struct pblk *pblk, struct nvm_rq *rqd)
+{
+	struct nvm_tgt_dev *dev = pblk->dev;
+
+#ifdef CONFIG_NVM_DEBUG
+	int ret;
+
+	ret = pblk_check_io(pblk, rqd);
+	if (ret)
+		return ret;
+#endif
+
+	atomic_inc(&pblk->inflight_io);
+
+	return nvm_submit_io_sync(dev, rqd);
+}
+
 static void pblk_bio_map_addr_endio(struct bio *bio)
 {
 	bio_put(bio);
@@ -597,7 +591,6 @@ static int pblk_line_submit_emeta_io(struct pblk *pblk, struct pblk_line *line,
 	int cmd_op, bio_op;
 	int i, j;
 	int ret;
-	DECLARE_COMPLETION_ONSTACK(wait);
 
 	if (dir == PBLK_WRITE) {
 		bio_op = REQ_OP_WRITE;
@@ -639,8 +632,6 @@ static int pblk_line_submit_emeta_io(struct pblk *pblk, struct pblk_line *line,
 	rqd.dma_ppa_list = dma_ppa_list;
 	rqd.opcode = cmd_op;
 	rqd.nr_ppas = rq_ppas;
-	rqd.end_io = pblk_end_io_sync;
-	rqd.private = &wait;
 
 	if (dir == PBLK_WRITE) {
 		struct pblk_sec_meta *meta_list = rqd.meta_list;
@@ -694,19 +685,14 @@ static int pblk_line_submit_emeta_io(struct pblk *pblk, struct pblk_line *line,
 		}
 	}
 
-	ret = pblk_submit_io(pblk, &rqd);
+	ret = pblk_submit_io_sync(pblk, &rqd);
 	if (ret) {
 		pr_err("pblk: emeta I/O submission failed: %d\n", ret);
 		bio_put(bio);
 		goto free_rqd_dma;
 	}
 
-	if (!wait_for_completion_io_timeout(&wait,
-				msecs_to_jiffies(PBLK_COMMAND_TIMEOUT_MS))) {
-		pr_err("pblk: emeta I/O timed out\n");
-	}
 	atomic_dec(&pblk->inflight_io);
-	reinit_completion(&wait);
 
 	if (rqd.error) {
 		if (dir == PBLK_WRITE)
@@ -750,7 +736,6 @@ static int pblk_line_submit_smeta_io(struct pblk *pblk, struct pblk_line *line,
 	int i, ret;
 	int cmd_op, bio_op;
 	int flags;
-	DECLARE_COMPLETION_ONSTACK(wait);
 
 	if (dir == PBLK_WRITE) {
 		bio_op = REQ_OP_WRITE;
@@ -787,8 +772,6 @@ static int pblk_line_submit_smeta_io(struct pblk *pblk, struct pblk_line *line,
 	rqd.opcode = cmd_op;
 	rqd.flags = flags;
 	rqd.nr_ppas = lm->smeta_sec;
-	rqd.end_io = pblk_end_io_sync;
-	rqd.private = &wait;
 
 	for (i = 0; i < lm->smeta_sec; i++, paddr++) {
 		struct pblk_sec_meta *meta_list = rqd.meta_list;
@@ -807,17 +790,13 @@ static int pblk_line_submit_smeta_io(struct pblk *pblk, struct pblk_line *line,
 	 * the write thread is the only one sending write and erase commands,
 	 * there is no need to take the LUN semaphore.
 	 */
-	ret = pblk_submit_io(pblk, &rqd);
+	ret = pblk_submit_io_sync(pblk, &rqd);
 	if (ret) {
 		pr_err("pblk: smeta I/O submission failed: %d\n", ret);
 		bio_put(bio);
 		goto free_ppa_list;
 	}
 
-	if (!wait_for_completion_io_timeout(&wait,
-				msecs_to_jiffies(PBLK_COMMAND_TIMEOUT_MS))) {
-		pr_err("pblk: smeta I/O timed out\n");
-	}
 	atomic_dec(&pblk->inflight_io);
 
 	if (rqd.error) {
@@ -861,19 +840,15 @@ static int pblk_blk_erase_sync(struct pblk *pblk, struct ppa_addr ppa)
 {
 	struct nvm_rq rqd;
 	int ret = 0;
-	DECLARE_COMPLETION_ONSTACK(wait);
 
 	memset(&rqd, 0, sizeof(struct nvm_rq));
 
 	pblk_setup_e_rq(pblk, &rqd, ppa);
 
-	rqd.end_io = pblk_end_io_sync;
-	rqd.private = &wait;
-
 	/* The write thread schedules erases so that it minimizes disturbances
 	 * with writes. Thus, there is no need to take the LUN semaphore.
 	 */
-	ret = pblk_submit_io(pblk, &rqd);
+	ret = pblk_submit_io_sync(pblk, &rqd);
 	if (ret) {
 		struct nvm_tgt_dev *dev = pblk->dev;
 		struct nvm_geo *geo = &dev->geo;
@@ -886,11 +861,6 @@ static int pblk_blk_erase_sync(struct pblk *pblk, struct ppa_addr ppa)
 		goto out;
 	}
 
-	if (!wait_for_completion_io_timeout(&wait,
-				msecs_to_jiffies(PBLK_COMMAND_TIMEOUT_MS))) {
-		pr_err("pblk: sync erase timed out\n");
-	}
-
 out:
 	rqd.private = pblk;
 	__pblk_end_io_erase(pblk, &rqd);
diff --git a/drivers/lightnvm/pblk-read.c b/drivers/lightnvm/pblk-read.c
index 71c58503f1a4..ca79d8fb3e60 100644
--- a/drivers/lightnvm/pblk-read.c
+++ b/drivers/lightnvm/pblk-read.c
@@ -207,7 +207,6 @@ static int pblk_fill_partial_read_bio(struct pblk *pblk, struct nvm_rq *rqd,
 	int nr_secs = rqd->nr_ppas;
 	int nr_holes = nr_secs - bitmap_weight(read_bitmap, nr_secs);
 	int i, ret, hole;
-	DECLARE_COMPLETION_ONSTACK(wait);
 
 	/* Re-use allocated memory for intermediate lbas */
 	lba_list_mem = (((void *)rqd->ppa_list) + pblk_dma_ppa_size);
@@ -232,8 +231,6 @@ static int pblk_fill_partial_read_bio(struct pblk *pblk, struct nvm_rq *rqd,
 	rqd->bio = new_bio;
 	rqd->nr_ppas = nr_holes;
 	rqd->flags = pblk_set_read_mode(pblk, PBLK_READ_RANDOM);
-	rqd->end_io = pblk_end_io_sync;
-	rqd->private = &wait;
 
 	if (unlikely(nr_holes == 1)) {
 		ppa_ptr = rqd->ppa_list;
@@ -241,18 +238,13 @@ static int pblk_fill_partial_read_bio(struct pblk *pblk, struct nvm_rq *rqd,
 		rqd->ppa_addr = rqd->ppa_list[0];
 	}
 
-	ret = pblk_submit_read_io(pblk, rqd);
+	ret = pblk_submit_io_sync(pblk, rqd);
 	if (ret) {
 		bio_put(rqd->bio);
-		pr_err("pblk: read IO submission failed\n");
+		pr_err("pblk: sync read IO submission failed\n");
 		goto err;
 	}
 
-	if (!wait_for_completion_io_timeout(&wait,
-				msecs_to_jiffies(PBLK_COMMAND_TIMEOUT_MS))) {
-		pr_err("pblk: partial read I/O timed out\n");
-	}
-
 	if (rqd->error) {
 		atomic_long_inc(&pblk->read_failed);
 #ifdef CONFIG_NVM_DEBUG
@@ -537,7 +529,6 @@ int pblk_submit_read_gc(struct pblk *pblk, struct pblk_gc_rq *gc_rq)
 	struct nvm_rq rqd;
 	int data_len;
 	int ret = NVM_IO_OK;
-	DECLARE_COMPLETION_ONSTACK(wait);
 
 	memset(&rqd, 0, sizeof(struct nvm_rq));
 
@@ -577,22 +568,16 @@ int pblk_submit_read_gc(struct pblk *pblk, struct pblk_gc_rq *gc_rq)
 	bio_set_op_attrs(bio, REQ_OP_READ, 0);
 
 	rqd.opcode = NVM_OP_PREAD;
-	rqd.end_io = pblk_end_io_sync;
-	rqd.private = &wait;
 	rqd.nr_ppas = gc_rq->secs_to_gc;
 	rqd.flags = pblk_set_read_mode(pblk, PBLK_READ_RANDOM);
 	rqd.bio = bio;
 
-	if (pblk_submit_read_io(pblk, &rqd)) {
+	if (pblk_submit_io_sync(pblk, &rqd)) {
 		ret = -EIO;
 		pr_err("pblk: GC read request failed\n");
 		goto err_free_bio;
 	}
 
-	if (!wait_for_completion_io_timeout(&wait,
-				msecs_to_jiffies(PBLK_COMMAND_TIMEOUT_MS))) {
-		pr_err("pblk: GC read I/O timed out\n");
-	}
 	atomic_dec(&pblk->inflight_io);
 
 	if (rqd.error) {
diff --git a/drivers/lightnvm/pblk-recovery.c b/drivers/lightnvm/pblk-recovery.c
index 9772a947ca4f..eadb3eb5d4dc 100644
--- a/drivers/lightnvm/pblk-recovery.c
+++ b/drivers/lightnvm/pblk-recovery.c
@@ -216,7 +216,6 @@ static int pblk_recov_read_oob(struct pblk *pblk, struct pblk_line *line,
 	int rq_ppas, rq_len;
 	int i, j;
 	int ret = 0;
-	DECLARE_COMPLETION_ONSTACK(wait);
 
 	ppa_list = p.ppa_list;
 	meta_list = p.meta_list;
@@ -253,8 +252,6 @@ static int pblk_recov_read_oob(struct pblk *pblk, struct pblk_line *line,
 	rqd->ppa_list = ppa_list;
 	rqd->dma_ppa_list = dma_ppa_list;
 	rqd->dma_meta_list = dma_meta_list;
-	rqd->end_io = pblk_end_io_sync;
-	rqd->private = &wait;
 
 	if (pblk_io_aligned(pblk, rq_ppas))
 		rqd->flags = pblk_set_read_mode(pblk, PBLK_READ_SEQUENTIAL);
@@ -280,19 +277,13 @@ static int pblk_recov_read_oob(struct pblk *pblk, struct pblk_line *line,
 	}
 
 	/* If read fails, more padding is needed */
-	ret = pblk_submit_io(pblk, rqd);
+	ret = pblk_submit_io_sync(pblk, rqd);
 	if (ret) {
 		pr_err("pblk: I/O submission failed: %d\n", ret);
 		return ret;
 	}
 
-	if (!wait_for_completion_io_timeout(&wait,
-				msecs_to_jiffies(PBLK_COMMAND_TIMEOUT_MS))) {
-		pr_err("pblk: L2P recovery read timed out\n");
-		return -EINTR;
-	}
 	atomic_dec(&pblk->inflight_io);
-	reinit_completion(&wait);
 
 	/* At this point, the read should not fail. If it does, it is a problem
 	 * we cannot recover from here. Need FTL log.
@@ -504,7 +495,6 @@ static int pblk_recov_scan_all_oob(struct pblk *pblk, struct pblk_line *line,
 	int ret = 0;
 	int rec_round;
 	int left_ppas = pblk_calc_sec_in_line(pblk, line) - line->cur_sec;
-	DECLARE_COMPLETION_ONSTACK(wait);
 
 	ppa_list = p.ppa_list;
 	meta_list = p.meta_list;
@@ -539,8 +529,6 @@ static int pblk_recov_scan_all_oob(struct pblk *pblk, struct pblk_line *line,
 	rqd->ppa_list = ppa_list;
 	rqd->dma_ppa_list = dma_ppa_list;
 	rqd->dma_meta_list = dma_meta_list;
-	rqd->end_io = pblk_end_io_sync;
-	rqd->private = &wait;
 
 	if (pblk_io_aligned(pblk, rq_ppas))
 		rqd->flags = pblk_set_read_mode(pblk, PBLK_READ_SEQUENTIAL);
@@ -566,18 +554,13 @@ static int pblk_recov_scan_all_oob(struct pblk *pblk, struct pblk_line *line,
 				addr_to_gen_ppa(pblk, w_ptr, line->id);
 	}
 
-	ret = pblk_submit_io(pblk, rqd);
+	ret = pblk_submit_io_sync(pblk, rqd);
 	if (ret) {
 		pr_err("pblk: I/O submission failed: %d\n", ret);
 		return ret;
 	}
 
-	if (!wait_for_completion_io_timeout(&wait,
-				msecs_to_jiffies(PBLK_COMMAND_TIMEOUT_MS))) {
-		pr_err("pblk: L2P recovery read timed out\n");
-	}
 	atomic_dec(&pblk->inflight_io);
-	reinit_completion(&wait);
 
 	/* This should not happen since the read failed during normal recovery,
 	 * but the media works funny sometimes...
@@ -645,7 +628,6 @@ static int pblk_recov_scan_oob(struct pblk *pblk, struct pblk_line *line,
 	int i, j;
 	int ret = 0;
 	int left_ppas = pblk_calc_sec_in_line(pblk, line);
-	DECLARE_COMPLETION_ONSTACK(wait);
 
 	ppa_list = p.ppa_list;
 	meta_list = p.meta_list;
@@ -678,8 +660,6 @@ static int pblk_recov_scan_oob(struct pblk *pblk, struct pblk_line *line,
 	rqd->ppa_list = ppa_list;
 	rqd->dma_ppa_list = dma_ppa_list;
 	rqd->dma_meta_list = dma_meta_list;
-	rqd->end_io = pblk_end_io_sync;
-	rqd->private = &wait;
 
 	if (pblk_io_aligned(pblk, rq_ppas))
 		rqd->flags = pblk_set_read_mode(pblk, PBLK_READ_SEQUENTIAL);
@@ -705,19 +685,14 @@ static int pblk_recov_scan_oob(struct pblk *pblk, struct pblk_line *line,
 				addr_to_gen_ppa(pblk, paddr, line->id);
 	}
 
-	ret = pblk_submit_io(pblk, rqd);
+	ret = pblk_submit_io_sync(pblk, rqd);
 	if (ret) {
 		pr_err("pblk: I/O submission failed: %d\n", ret);
 		bio_put(bio);
 		return ret;
 	}
 
-	if (!wait_for_completion_io_timeout(&wait,
-				msecs_to_jiffies(PBLK_COMMAND_TIMEOUT_MS))) {
-		pr_err("pblk: L2P recovery read timed out\n");
-	}
 	atomic_dec(&pblk->inflight_io);
-	reinit_completion(&wait);
 
 	/* Reached the end of the written line */
 	if (rqd->error) {
diff --git a/drivers/lightnvm/pblk.h b/drivers/lightnvm/pblk.h
index 6c9ea9a93704..6b64288de6f7 100644
--- a/drivers/lightnvm/pblk.h
+++ b/drivers/lightnvm/pblk.h
@@ -714,6 +714,7 @@ void pblk_discard(struct pblk *pblk, struct bio *bio);
 void pblk_log_write_err(struct pblk *pblk, struct nvm_rq *rqd);
 void pblk_log_read_err(struct pblk *pblk, struct nvm_rq *rqd);
 int pblk_submit_io(struct pblk *pblk, struct nvm_rq *rqd);
+int pblk_submit_io_sync(struct pblk *pblk, struct nvm_rq *rqd);
 int pblk_submit_meta_io(struct pblk *pblk, struct pblk_line *meta_line);
 struct bio *pblk_bio_map_addr(struct pblk *pblk, void *data,
 			      unsigned int nr_secs, unsigned int len,
@@ -1203,7 +1204,6 @@ static inline void pblk_print_failed_rqd(struct pblk *pblk, struct nvm_rq *rqd,
 
 	pr_err("error:%d, ppa_status:%llx\n", error, rqd->ppa_status);
 }
-#endif
 
 static inline int pblk_boundary_ppa_checks(struct nvm_tgt_dev *tgt_dev,
 				       struct ppa_addr *ppas, int nr_ppas)
@@ -1224,14 +1224,50 @@ static inline int pblk_boundary_ppa_checks(struct nvm_tgt_dev *tgt_dev,
 				ppa->g.sec < geo->sec_per_pg)
 			continue;
 
-#ifdef CONFIG_NVM_DEBUG
 		print_ppa(ppa, "boundary", i);
-#endif
+
 		return 1;
 	}
 	return 0;
 }
 
+static inline int pblk_check_io(struct pblk *pblk, struct nvm_rq *rqd)
+{
+	struct nvm_tgt_dev *dev = pblk->dev;
+	struct ppa_addr *ppa_list;
+
+	ppa_list = (rqd->nr_ppas > 1) ? rqd->ppa_list : &rqd->ppa_addr;
+
+	if (pblk_boundary_ppa_checks(dev, ppa_list, rqd->nr_ppas)) {
+		WARN_ON(1);
+		return -EINVAL;
+	}
+
+	if (rqd->opcode == NVM_OP_PWRITE) {
+		struct pblk_line *line;
+		struct ppa_addr ppa;
+		int i;
+
+		for (i = 0; i < rqd->nr_ppas; i++) {
+			ppa = ppa_list[i];
+			line = &pblk->lines[pblk_dev_ppa_to_line(ppa)];
+
+			spin_lock(&line->lock);
+			if (line->state != PBLK_LINESTATE_OPEN) {
+				pr_err("pblk: bad ppa: line:%d,state:%d\n",
+							line->id, line->state);
+				WARN_ON(1);
+				spin_unlock(&line->lock);
+				return -EINVAL;
+			}
+			spin_unlock(&line->lock);
+		}
+	}
+
+	return 0;
+}
+#endif
+
 static inline int pblk_boundary_paddr_checks(struct pblk *pblk, u64 paddr)
 {
 	struct pblk_line_meta *lm = &pblk->lm;
diff --git a/drivers/nvme/host/lightnvm.c b/drivers/nvme/host/lightnvm.c
index 6017153c2439..8fc949c5b49b 100644
--- a/drivers/nvme/host/lightnvm.c
+++ b/drivers/nvme/host/lightnvm.c
@@ -492,34 +492,47 @@ static void nvme_nvm_end_io(struct request *rq, blk_status_t status)
 	blk_mq_free_request(rq);
 }
 
-static int nvme_nvm_submit_io(struct nvm_dev *dev, struct nvm_rq *rqd)
+static struct request *nvme_nvm_alloc_request(struct request_queue *q,
+					      struct nvm_rq *rqd,
+					      struct nvme_nvm_command *cmd)
 {
-	struct request_queue *q = dev->q;
 	struct nvme_ns *ns = q->queuedata;
 	struct request *rq;
-	struct bio *bio = rqd->bio;
-	struct nvme_nvm_command *cmd;
-
-	cmd = kzalloc(sizeof(struct nvme_nvm_command), GFP_KERNEL);
-	if (!cmd)
-		return -ENOMEM;
 
 	nvme_nvm_rqtocmd(rqd, ns, cmd);
 
 	rq = nvme_alloc_request(q, (struct nvme_command *)cmd, 0, NVME_QID_ANY);
-	if (IS_ERR(rq)) {
-		kfree(cmd);
-		return PTR_ERR(rq);
-	}
+	if (IS_ERR(rq))
+		return rq;
+
 	rq->cmd_flags &= ~REQ_FAILFAST_DRIVER;
 
-	if (bio) {
-		blk_init_request_from_bio(rq, bio);
+	if (rqd->bio) {
+		blk_init_request_from_bio(rq, rqd->bio);
 	} else {
 		rq->ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, IOPRIO_NORM);
 		rq->__data_len = 0;
 	}
 
+	return rq;
+}
+
+static int nvme_nvm_submit_io(struct nvm_dev *dev, struct nvm_rq *rqd)
+{
+	struct request_queue *q = dev->q;
+	struct nvme_nvm_command *cmd;
+	struct request *rq;
+
+	cmd = kzalloc(sizeof(struct nvme_nvm_command), GFP_KERNEL);
+	if (!cmd)
+		return -ENOMEM;
+
+	rq = nvme_nvm_alloc_request(q, rqd, cmd);
+	if (IS_ERR(rq)) {
+		kfree(cmd);
+		return PTR_ERR(rq);
+	}
+
 	rq->end_io_data = rqd;
 
 	blk_execute_rq_nowait(q, NULL, rq, 0, nvme_nvm_end_io);
@@ -527,6 +540,34 @@ static int nvme_nvm_submit_io(struct nvm_dev *dev, struct nvm_rq *rqd)
 	return 0;
 }
 
+static int nvme_nvm_submit_io_sync(struct nvm_dev *dev, struct nvm_rq *rqd)
+{
+	struct request_queue *q = dev->q;
+	struct request *rq;
+	struct nvme_nvm_command cmd;
+	int ret = 0;
+
+	memset(&cmd, 0, sizeof(struct nvme_nvm_command));
+
+	rq = nvme_nvm_alloc_request(q, rqd, &cmd);
+	if (IS_ERR(rq))
+		return PTR_ERR(rq);
+
+	/* I/Os can fail and the error is signaled through rqd. Callers must
+	 * handle the error accordingly.
+	 */
+	blk_execute_rq(q, NULL, rq, 0);
+	if (nvme_req(rq)->flags & NVME_REQ_CANCELLED)
+		ret = -EINTR;
+
+	rqd->ppa_status = le64_to_cpu(nvme_req(rq)->result.u64);
+	rqd->error = nvme_req(rq)->status;
+
+	blk_mq_free_request(rq);
+
+	return ret;
+}
+
 static void *nvme_nvm_create_dma_pool(struct nvm_dev *nvmdev, char *name)
 {
 	struct nvme_ns *ns = nvmdev->q->queuedata;
@@ -562,6 +603,7 @@ static struct nvm_dev_ops nvme_nvm_dev_ops = {
 	.set_bb_tbl		= nvme_nvm_set_bb_tbl,
 
 	.submit_io		= nvme_nvm_submit_io,
+	.submit_io_sync		= nvme_nvm_submit_io_sync,
 
 	.create_dma_pool	= nvme_nvm_create_dma_pool,
 	.destroy_dma_pool	= nvme_nvm_destroy_dma_pool,
diff --git a/include/linux/lightnvm.h b/include/linux/lightnvm.h
index 4f0e4a0fd204..b7f111ff4d3b 100644
--- a/include/linux/lightnvm.h
+++ b/include/linux/lightnvm.h
@@ -56,6 +56,7 @@ typedef int (nvm_get_l2p_tbl_fn)(struct nvm_dev *, u64, u32,
 typedef int (nvm_op_bb_tbl_fn)(struct nvm_dev *, struct ppa_addr, u8 *);
 typedef int (nvm_op_set_bb_fn)(struct nvm_dev *, struct ppa_addr *, int, int);
 typedef int (nvm_submit_io_fn)(struct nvm_dev *, struct nvm_rq *);
+typedef int (nvm_submit_io_sync_fn)(struct nvm_dev *, struct nvm_rq *);
 typedef void *(nvm_create_dma_pool_fn)(struct nvm_dev *, char *);
 typedef void (nvm_destroy_dma_pool_fn)(void *);
 typedef void *(nvm_dev_dma_alloc_fn)(struct nvm_dev *, void *, gfp_t,
@@ -69,6 +70,7 @@ struct nvm_dev_ops {
 	nvm_op_set_bb_fn	*set_bb_tbl;
 
 	nvm_submit_io_fn	*submit_io;
+	nvm_submit_io_sync_fn	*submit_io_sync;
 
 	nvm_create_dma_pool_fn	*create_dma_pool;
 	nvm_destroy_dma_pool_fn	*destroy_dma_pool;
@@ -477,6 +479,7 @@ extern int nvm_set_tgt_bb_tbl(struct nvm_tgt_dev *, struct ppa_addr *,
 			      int, int);
 extern int nvm_max_phys_sects(struct nvm_tgt_dev *);
 extern int nvm_submit_io(struct nvm_tgt_dev *, struct nvm_rq *);
+extern int nvm_submit_io_sync(struct nvm_tgt_dev *, struct nvm_rq *);
 extern int nvm_erase_sync(struct nvm_tgt_dev *, struct ppa_addr *, int);
 extern int nvm_get_l2p_tbl(struct nvm_tgt_dev *, u64, u32, nvm_l2p_update_fn *,
 			   void *);
-- 
2.7.4