[linux-block.git] / drivers / lightnvm / pblk-read.c

/*
 * 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-read.c - pblk's read path
 */

#include "pblk.h"

/*
 * There is no guarantee that the value read from cache has not been updated and
 * resides at another location in the cache. We guarantee though that if the
 * value is read from the cache, it belongs to the mapped lba. In order to
 * guarantee and order between writes and reads are ordered, a flush must be
 * issued.
 */
static int pblk_read_from_cache(struct pblk *pblk, struct bio *bio,
				sector_t lba, struct ppa_addr ppa,
				int bio_iter, bool advanced_bio)
{
#ifdef CONFIG_NVM_DEBUG
	/* Callers must ensure that the ppa points to a cache address */
	BUG_ON(pblk_ppa_empty(ppa));
	BUG_ON(!pblk_addr_in_cache(ppa));
#endif

	return pblk_rb_copy_to_bio(&pblk->rwb, bio, lba, ppa,
						bio_iter, advanced_bio);
}

static void pblk_read_ppalist_rq(struct pblk *pblk, struct nvm_rq *rqd,
				 sector_t blba, unsigned long *read_bitmap)
{
	struct pblk_sec_meta *meta_list = rqd->meta_list;
	struct bio *bio = rqd->bio;
	struct ppa_addr ppas[PBLK_MAX_REQ_ADDRS];
	int nr_secs = rqd->nr_ppas;
	bool advanced_bio = false;
	int i, j = 0;

	pblk_lookup_l2p_seq(pblk, ppas, blba, nr_secs);

	for (i = 0; i < nr_secs; i++) {
		struct ppa_addr p = ppas[i];
		sector_t lba = blba + i;

retry:
		if (pblk_ppa_empty(p)) {
			WARN_ON(test_and_set_bit(i, read_bitmap));
			meta_list[i].lba = cpu_to_le64(ADDR_EMPTY);

			if (unlikely(!advanced_bio)) {
				bio_advance(bio, (i) * PBLK_EXPOSED_PAGE_SIZE);
				advanced_bio = true;
			}

			goto next;
		}

		/* Try to read from write buffer. The address is later checked
		 * on the write buffer to prevent retrieving overwritten data.
		 */
		if (pblk_addr_in_cache(p)) {
			if (!pblk_read_from_cache(pblk, bio, lba, p, i,
								advanced_bio)) {
				pblk_lookup_l2p_seq(pblk, &p, lba, 1);
				goto retry;
			}
			WARN_ON(test_and_set_bit(i, read_bitmap));
			meta_list[i].lba = cpu_to_le64(lba);
			advanced_bio = true;
#ifdef CONFIG_NVM_DEBUG
			atomic_long_inc(&pblk->cache_reads);
#endif
		} else {
			/* Read from media non-cached sectors */
			rqd->ppa_list[j++] = p;
		}

next:
		if (advanced_bio)
			bio_advance(bio, PBLK_EXPOSED_PAGE_SIZE);
	}

	if (pblk_io_aligned(pblk, nr_secs))
		rqd->flags = pblk_set_read_mode(pblk, PBLK_READ_SEQUENTIAL);
	else
		rqd->flags = pblk_set_read_mode(pblk, PBLK_READ_RANDOM);

#ifdef CONFIG_NVM_DEBUG
	atomic_long_add(nr_secs, &pblk->inflight_reads);
#endif
}

static int pblk_submit_read_io(struct pblk *pblk, struct nvm_rq *rqd)
{
	int err;

	err = pblk_submit_io(pblk, rqd);
	if (err)
		return NVM_IO_ERR;

	return NVM_IO_OK;
}

static void pblk_read_check(struct pblk *pblk, struct nvm_rq *rqd,
			   sector_t blba)
{
	struct pblk_sec_meta *meta_list = rqd->meta_list;
	int nr_lbas = rqd->nr_ppas;
	int i;

	for (i = 0; i < nr_lbas; i++) {
		u64 lba = le64_to_cpu(meta_list[i].lba);

		if (lba == ADDR_EMPTY)
			continue;

		WARN(lba != blba + i, "pblk: corrupted read LBA\n");
	}
}

static void pblk_read_put_rqd_kref(struct pblk *pblk, struct nvm_rq *rqd)
{
	struct ppa_addr *ppa_list;
	int i;

	ppa_list = (rqd->nr_ppas > 1) ? rqd->ppa_list : &rqd->ppa_addr;

	for (i = 0; i < rqd->nr_ppas; i++) {
		struct ppa_addr ppa = ppa_list[i];
		struct pblk_line *line;

		line = &pblk->lines[pblk_dev_ppa_to_line(ppa)];
		kref_put(&line->ref, pblk_line_put_wq);
	}
}

static void pblk_end_user_read(struct bio *bio)
{
#ifdef CONFIG_NVM_DEBUG
	WARN_ONCE(bio->bi_status, "pblk: corrupted read bio\n");
#endif
	bio_endio(bio);
	bio_put(bio);
}

static void __pblk_end_io_read(struct pblk *pblk, struct nvm_rq *rqd,
			       bool put_line)
{
	struct pblk_g_ctx *r_ctx = nvm_rq_to_pdu(rqd);
	struct bio *bio = rqd->bio;

	if (rqd->error)
		pblk_log_read_err(pblk, rqd);
#ifdef CONFIG_NVM_DEBUG
	else
		WARN_ONCE(bio->bi_status, "pblk: corrupted read error\n");
#endif

	pblk_read_check(pblk, rqd, r_ctx->lba);

	bio_put(bio);
	if (r_ctx->private)
		pblk_end_user_read((struct bio *)r_ctx->private);

	if (put_line)
		pblk_read_put_rqd_kref(pblk, rqd);

#ifdef CONFIG_NVM_DEBUG
	atomic_long_add(rqd->nr_ppas, &pblk->sync_reads);
	atomic_long_sub(rqd->nr_ppas, &pblk->inflight_reads);
#endif

	pblk_free_rqd(pblk, rqd, PBLK_READ);
	atomic_dec(&pblk->inflight_io);
}

static void pblk_end_io_read(struct nvm_rq *rqd)
{
	struct pblk *pblk = rqd->private;

	__pblk_end_io_read(pblk, rqd, true);
}

static int pblk_fill_partial_read_bio(struct pblk *pblk, struct nvm_rq *rqd,
				      unsigned int bio_init_idx,
				      unsigned long *read_bitmap)
{
	struct bio *new_bio, *bio = rqd->bio;
	struct pblk_sec_meta *meta_list = rqd->meta_list;
	struct bio_vec src_bv, dst_bv;
	void *ppa_ptr = NULL;
	void *src_p, *dst_p;
	dma_addr_t dma_ppa_list = 0;
	__le64 *lba_list_mem, *lba_list_media;
	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);
	lba_list_media = (((void *)rqd->ppa_list) + 2 * pblk_dma_ppa_size);

	new_bio = bio_alloc(GFP_KERNEL, nr_holes);

	if (pblk_bio_add_pages(pblk, new_bio, GFP_KERNEL, nr_holes))
		goto err;

	if (nr_holes != new_bio->bi_vcnt) {
		pr_err("pblk: malformed bio\n");
		goto err;
	}

	for (i = 0; i < nr_secs; i++)
		lba_list_mem[i] = meta_list[i].lba;

	new_bio->bi_iter.bi_sector = 0; /* internal bio */
	bio_set_op_attrs(new_bio, REQ_OP_READ, 0);

	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_secs > 1 && nr_holes == 1)) {
		ppa_ptr = rqd->ppa_list;
		dma_ppa_list = rqd->dma_ppa_list;
		rqd->ppa_addr = rqd->ppa_list[0];
	}

	ret = pblk_submit_read_io(pblk, rqd);
	if (ret) {
		bio_put(rqd->bio);
		pr_err("pblk: 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
		pblk_print_failed_rqd(pblk, rqd, rqd->error);
#endif
	}

	if (unlikely(nr_secs > 1 && nr_holes == 1)) {
		struct ppa_addr ppa;

		ppa = rqd->ppa_addr;
		rqd->ppa_list = ppa_ptr;
		rqd->dma_ppa_list = dma_ppa_list;
		rqd->ppa_list[0] = ppa;
	}

	for (i = 0; i < nr_secs; i++) {
		lba_list_media[i] = meta_list[i].lba;
		meta_list[i].lba = lba_list_mem[i];
	}

	/* Fill the holes in the original bio */
	i = 0;
	hole = find_first_zero_bit(read_bitmap, nr_secs);
	do {
		int line_id = pblk_dev_ppa_to_line(rqd->ppa_list[i]);
		struct pblk_line *line = &pblk->lines[line_id];

		kref_put(&line->ref, pblk_line_put);

		meta_list[hole].lba = lba_list_media[i];

		src_bv = new_bio->bi_io_vec[i++];
		dst_bv = bio->bi_io_vec[bio_init_idx + hole];

		src_p = kmap_atomic(src_bv.bv_page);
		dst_p = kmap_atomic(dst_bv.bv_page);

		memcpy(dst_p + dst_bv.bv_offset,
			src_p + src_bv.bv_offset,
			PBLK_EXPOSED_PAGE_SIZE);

		kunmap_atomic(src_p);
		kunmap_atomic(dst_p);

		mempool_free(src_bv.bv_page, pblk->page_bio_pool);

		hole = find_next_zero_bit(read_bitmap, nr_secs, hole + 1);
	} while (hole < nr_secs);

	bio_put(new_bio);

	/* Complete the original bio and associated request */
	bio_endio(bio);
	rqd->bio = bio;
	rqd->nr_ppas = nr_secs;

	__pblk_end_io_read(pblk, rqd, false);
	return NVM_IO_OK;

err:
	/* Free allocated pages in new bio */
	pblk_bio_free_pages(pblk, bio, 0, new_bio->bi_vcnt);
	__pblk_end_io_read(pblk, rqd, false);
	return NVM_IO_ERR;
}

static void pblk_read_rq(struct pblk *pblk, struct nvm_rq *rqd,
			 sector_t lba, unsigned long *read_bitmap)
{
	struct pblk_sec_meta *meta_list = rqd->meta_list;
	struct bio *bio = rqd->bio;
	struct ppa_addr ppa;

	pblk_lookup_l2p_seq(pblk, &ppa, lba, 1);

#ifdef CONFIG_NVM_DEBUG
	atomic_long_inc(&pblk->inflight_reads);
#endif

retry:
	if (pblk_ppa_empty(ppa)) {
		WARN_ON(test_and_set_bit(0, read_bitmap));
		meta_list[0].lba = cpu_to_le64(ADDR_EMPTY);
		return;
	}

	/* Try to read from write buffer. The address is later checked on the
	 * write buffer to prevent retrieving overwritten data.
	 */
	if (pblk_addr_in_cache(ppa)) {
		if (!pblk_read_from_cache(pblk, bio, lba, ppa, 0, 1)) {
			pblk_lookup_l2p_seq(pblk, &ppa, lba, 1);
			goto retry;
		}

		WARN_ON(test_and_set_bit(0, read_bitmap));
		meta_list[0].lba = cpu_to_le64(lba);

#ifdef CONFIG_NVM_DEBUG
		atomic_long_inc(&pblk->cache_reads);
#endif
	} else {
		rqd->ppa_addr = ppa;
	}

	rqd->flags = pblk_set_read_mode(pblk, PBLK_READ_RANDOM);
}

int pblk_submit_read(struct pblk *pblk, struct bio *bio)
{
	struct nvm_tgt_dev *dev = pblk->dev;
	sector_t blba = pblk_get_lba(bio);
	unsigned int nr_secs = pblk_get_secs(bio);
	struct pblk_g_ctx *r_ctx;
	struct nvm_rq *rqd;
	unsigned int bio_init_idx;
	unsigned long read_bitmap; /* Max 64 ppas per request */
	int ret = NVM_IO_ERR;

	/* logic error: lba out-of-bounds. Ignore read request */
	if (blba >= pblk->rl.nr_secs || nr_secs > PBLK_MAX_REQ_ADDRS) {
		WARN(1, "pblk: read lba out of bounds (lba:%llu, nr:%d)\n",
					(unsigned long long)blba, nr_secs);
		return NVM_IO_ERR;
	}

	bitmap_zero(&read_bitmap, nr_secs);

	rqd = pblk_alloc_rqd(pblk, PBLK_READ);

	rqd->opcode = NVM_OP_PREAD;
	rqd->bio = bio;
	rqd->nr_ppas = nr_secs;
	rqd->private = pblk;
	rqd->end_io = pblk_end_io_read;

	r_ctx = nvm_rq_to_pdu(rqd);
	r_ctx->lba = blba;

	/* Save the index for this bio's start. This is needed in case
	 * we need to fill a partial read.
	 */
	bio_init_idx = pblk_get_bi_idx(bio);

	rqd->meta_list = nvm_dev_dma_alloc(dev->parent, GFP_KERNEL,
							&rqd->dma_meta_list);
	if (!rqd->meta_list) {
		pr_err("pblk: not able to allocate ppa list\n");
		goto fail_rqd_free;
	}

	if (nr_secs > 1) {
		rqd->ppa_list = rqd->meta_list + pblk_dma_meta_size;
		rqd->dma_ppa_list = rqd->dma_meta_list + pblk_dma_meta_size;

		pblk_read_ppalist_rq(pblk, rqd, blba, &read_bitmap);
	} else {
		pblk_read_rq(pblk, rqd, blba, &read_bitmap);
	}

	bio_get(bio);
	if (bitmap_full(&read_bitmap, nr_secs)) {
		bio_endio(bio);
		atomic_inc(&pblk->inflight_io);
		__pblk_end_io_read(pblk, rqd, false);
		return NVM_IO_OK;
	}

	/* All sectors are to be read from the device */
	if (bitmap_empty(&read_bitmap, rqd->nr_ppas)) {
		struct bio *int_bio = NULL;

		/* Clone read bio to deal with read errors internally */
		int_bio = bio_clone_fast(bio, GFP_KERNEL, pblk_bio_set);
		if (!int_bio) {
			pr_err("pblk: could not clone read bio\n");
			return NVM_IO_ERR;
		}

		rqd->bio = int_bio;
		r_ctx->private = bio;

		ret = pblk_submit_read_io(pblk, rqd);
		if (ret) {
			pr_err("pblk: read IO submission failed\n");
			if (int_bio)
				bio_put(int_bio);
			return ret;
		}

		return NVM_IO_OK;
	}

	/* The read bio request could be partially filled by the write buffer,
	 * but there are some holes that need to be read from the drive.
	 */
	ret = pblk_fill_partial_read_bio(pblk, rqd, bio_init_idx, &read_bitmap);
	if (ret) {
		pr_err("pblk: failed to perform partial read\n");
		return ret;
	}

	return NVM_IO_OK;

fail_rqd_free:
	pblk_free_rqd(pblk, rqd, PBLK_READ);
	return ret;
}

static int read_ppalist_rq_gc(struct pblk *pblk, struct nvm_rq *rqd,
			      struct pblk_line *line, u64 *lba_list,
			      u64 *paddr_list_gc, unsigned int nr_secs)
{
	struct ppa_addr ppa_list_l2p[PBLK_MAX_REQ_ADDRS];
	struct ppa_addr ppa_gc;
	int valid_secs = 0;
	int i;

	pblk_lookup_l2p_rand(pblk, ppa_list_l2p, lba_list, nr_secs);

	for (i = 0; i < nr_secs; i++) {
		if (lba_list[i] == ADDR_EMPTY)
			continue;

		ppa_gc = addr_to_gen_ppa(pblk, paddr_list_gc[i], line->id);
		if (!pblk_ppa_comp(ppa_list_l2p[i], ppa_gc)) {
			paddr_list_gc[i] = lba_list[i] = ADDR_EMPTY;
			continue;
		}

		rqd->ppa_list[valid_secs++] = ppa_list_l2p[i];
	}

#ifdef CONFIG_NVM_DEBUG
	atomic_long_add(valid_secs, &pblk->inflight_reads);
#endif

	return valid_secs;
}

static int read_rq_gc(struct pblk *pblk, struct nvm_rq *rqd,
		      struct pblk_line *line, sector_t lba,
		      u64 paddr_gc)
{
	struct ppa_addr ppa_l2p, ppa_gc;
	int valid_secs = 0;

	if (lba == ADDR_EMPTY)
		goto out;

	/* logic error: lba out-of-bounds */
	if (lba >= pblk->rl.nr_secs) {
		WARN(1, "pblk: read lba out of bounds\n");
		goto out;
	}

	spin_lock(&pblk->trans_lock);
	ppa_l2p = pblk_trans_map_get(pblk, lba);
	spin_unlock(&pblk->trans_lock);

	ppa_gc = addr_to_gen_ppa(pblk, paddr_gc, line->id);
	if (!pblk_ppa_comp(ppa_l2p, ppa_gc))
		goto out;

	rqd->ppa_addr = ppa_l2p;
	valid_secs = 1;

#ifdef CONFIG_NVM_DEBUG
	atomic_long_inc(&pblk->inflight_reads);
#endif

out:
	return valid_secs;
}

int pblk_submit_read_gc(struct pblk *pblk, struct pblk_gc_rq *gc_rq)
{
	struct nvm_tgt_dev *dev = pblk->dev;
	struct nvm_geo *geo = &dev->geo;
	struct bio *bio;
	struct nvm_rq rqd;
	int data_len;
	int ret = NVM_IO_OK;
	DECLARE_COMPLETION_ONSTACK(wait);

	memset(&rqd, 0, sizeof(struct nvm_rq));

	rqd.meta_list = nvm_dev_dma_alloc(dev->parent, GFP_KERNEL,
							&rqd.dma_meta_list);
	if (!rqd.meta_list)
		return -ENOMEM;

	if (gc_rq->nr_secs > 1) {
		rqd.ppa_list = rqd.meta_list + pblk_dma_meta_size;
		rqd.dma_ppa_list = rqd.dma_meta_list + pblk_dma_meta_size;

		gc_rq->secs_to_gc = read_ppalist_rq_gc(pblk, &rqd, gc_rq->line,
							gc_rq->lba_list,
							gc_rq->paddr_list,
							gc_rq->nr_secs);
		if (gc_rq->secs_to_gc == 1)
			rqd.ppa_addr = rqd.ppa_list[0];
	} else {
		gc_rq->secs_to_gc = read_rq_gc(pblk, &rqd, gc_rq->line,
							gc_rq->lba_list[0],
							gc_rq->paddr_list[0]);
	}

	if (!(gc_rq->secs_to_gc))
		goto out;

	data_len = (gc_rq->secs_to_gc) * geo->sec_size;
	bio = pblk_bio_map_addr(pblk, gc_rq->data, gc_rq->secs_to_gc, data_len,
						PBLK_VMALLOC_META, GFP_KERNEL);
	if (IS_ERR(bio)) {
		pr_err("pblk: could not allocate GC bio (%lu)\n", PTR_ERR(bio));
		goto err_free_dma;
	}

	bio->bi_iter.bi_sector = 0; /* internal bio */
	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)) {
		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) {
		atomic_long_inc(&pblk->read_failed_gc);
#ifdef CONFIG_NVM_DEBUG
		pblk_print_failed_rqd(pblk, &rqd, rqd.error);
#endif
	}

#ifdef CONFIG_NVM_DEBUG
	atomic_long_add(gc_rq->secs_to_gc, &pblk->sync_reads);
	atomic_long_add(gc_rq->secs_to_gc, &pblk->recov_gc_reads);
	atomic_long_sub(gc_rq->secs_to_gc, &pblk->inflight_reads);
#endif

out:
	nvm_dev_dma_free(dev->parent, rqd.meta_list, rqd.dma_meta_list);
	return ret;

err_free_bio:
	bio_put(bio);
err_free_dma:
	nvm_dev_dma_free(dev->parent, rqd.meta_list, rqd.dma_meta_list);
	return ret;
}
Commit	Line	Data
a4bd217b JG	1	/*
	2	* Copyright (C) 2016 CNEX Labs
	3	* Initial release: Javier Gonzalez <javier@cnexlabs.com>
	4	* Matias Bjorling <matias@cnexlabs.com>
	5	*
	6	* This program is free software; you can redistribute it and/or
	7	* modify it under the terms of the GNU General Public License version
	8	* 2 as published by the Free Software Foundation.
	9	*
	10	* This program is distributed in the hope that it will be useful, but
	11	* WITHOUT ANY WARRANTY; without even the implied warranty of
	12	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	13	* General Public License for more details.
	14	*
	15	* pblk-read.c - pblk's read path
	16	*/
	17
	18	#include "pblk.h"
	19
	20	/*
	21	* There is no guarantee that the value read from cache has not been updated and
	22	* resides at another location in the cache. We guarantee though that if the
	23	* value is read from the cache, it belongs to the mapped lba. In order to
	24	* guarantee and order between writes and reads are ordered, a flush must be
	25	* issued.
	26	*/
	27	static int pblk_read_from_cache(struct pblk pblk, struct bio bio,
	28	sector_t lba, struct ppa_addr ppa,
75cb8e93	29	int bio_iter, bool advanced_bio)
a4bd217b JG	30	{
	31	#ifdef CONFIG_NVM_DEBUG
	32	/* Callers must ensure that the ppa points to a cache address */
	33	BUG_ON(pblk_ppa_empty(ppa));
	34	BUG_ON(!pblk_addr_in_cache(ppa));
	35	#endif
	36
75cb8e93 JG	37	return pblk_rb_copy_to_bio(&pblk->rwb, bio, lba, ppa,
75cb8e93 JG	38	bio_iter, advanced_bio);
a4bd217b JG	39	}
	40
	41	static void pblk_read_ppalist_rq(struct pblk pblk, struct nvm_rq rqd,
84454e6d	42	sector_t blba, unsigned long *read_bitmap)
a4bd217b	43	{
a4809fee	44	struct pblk_sec_meta *meta_list = rqd->meta_list;
a4bd217b JG	45	struct bio *bio = rqd->bio;
a4bd217b JG	46	struct ppa_addr ppas[PBLK_MAX_REQ_ADDRS];
a4bd217b	47	int nr_secs = rqd->nr_ppas;
75cb8e93	48	bool advanced_bio = false;
a4bd217b JG	49	int i, j = 0;
a4bd217b JG	50
a4bd217b JG	51	pblk_lookup_l2p_seq(pblk, ppas, blba, nr_secs);
	52
	53	for (i = 0; i < nr_secs; i++) {
	54	struct ppa_addr p = ppas[i];
	55	sector_t lba = blba + i;
	56
	57	retry:
	58	if (pblk_ppa_empty(p)) {
	59	WARN_ON(test_and_set_bit(i, read_bitmap));
a4809fee	60	meta_list[i].lba = cpu_to_le64(ADDR_EMPTY);
75cb8e93 JG	61
	62	if (unlikely(!advanced_bio)) {
	63	bio_advance(bio, (i) * PBLK_EXPOSED_PAGE_SIZE);
	64	advanced_bio = true;
	65	}
	66
	67	goto next;
a4bd217b JG	68	}
	69
	70	/* Try to read from write buffer. The address is later checked
	71	* on the write buffer to prevent retrieving overwritten data.
	72	*/
	73	if (pblk_addr_in_cache(p)) {
75cb8e93 JG	74	if (!pblk_read_from_cache(pblk, bio, lba, p, i,
75cb8e93 JG	75	advanced_bio)) {
a4bd217b JG	76	pblk_lookup_l2p_seq(pblk, &p, lba, 1);
	77	goto retry;
	78	}
	79	WARN_ON(test_and_set_bit(i, read_bitmap));
a4809fee	80	meta_list[i].lba = cpu_to_le64(lba);
75cb8e93	81	advanced_bio = true;
db7ada33 JG	82	#ifdef CONFIG_NVM_DEBUG
	83	atomic_long_inc(&pblk->cache_reads);
	84	#endif
a4bd217b JG	85	} else {
	86	/* Read from media non-cached sectors */
	87	rqd->ppa_list[j++] = p;
	88	}
	89
75cb8e93	90	next:
a4bd217b JG	91	if (advanced_bio)
	92	bio_advance(bio, PBLK_EXPOSED_PAGE_SIZE);
	93	}
	94
f9c10152 JG	95	if (pblk_io_aligned(pblk, nr_secs))
	96	rqd->flags = pblk_set_read_mode(pblk, PBLK_READ_SEQUENTIAL);
	97	else
	98	rqd->flags = pblk_set_read_mode(pblk, PBLK_READ_RANDOM);
	99
a4bd217b JG	100	#ifdef CONFIG_NVM_DEBUG
	101	atomic_long_add(nr_secs, &pblk->inflight_reads);
	102	#endif
	103	}
	104
	105	static int pblk_submit_read_io(struct pblk pblk, struct nvm_rq rqd)
	106	{
	107	int err;
	108
a4bd217b JG	109	err = pblk_submit_io(pblk, rqd);
	110	if (err)
	111	return NVM_IO_ERR;
	112
	113	return NVM_IO_OK;
	114	}
	115
a4809fee JG	116	static void pblk_read_check(struct pblk pblk, struct nvm_rq rqd,
	117	sector_t blba)
	118	{
	119	struct pblk_sec_meta *meta_list = rqd->meta_list;
	120	int nr_lbas = rqd->nr_ppas;
	121	int i;
	122
	123	for (i = 0; i < nr_lbas; i++) {
	124	u64 lba = le64_to_cpu(meta_list[i].lba);
	125
	126	if (lba == ADDR_EMPTY)
	127	continue;
	128
	129	WARN(lba != blba + i, "pblk: corrupted read LBA\n");
	130	}
	131	}
	132
7bd4d370 JG	133	static void pblk_read_put_rqd_kref(struct pblk pblk, struct nvm_rq rqd)
	134	{
	135	struct ppa_addr *ppa_list;
	136	int i;
	137
	138	ppa_list = (rqd->nr_ppas > 1) ? rqd->ppa_list : &rqd->ppa_addr;
	139
	140	for (i = 0; i < rqd->nr_ppas; i++) {
	141	struct ppa_addr ppa = ppa_list[i];
	142	struct pblk_line *line;
	143
	144	line = &pblk->lines[pblk_dev_ppa_to_line(ppa)];
	145	kref_put(&line->ref, pblk_line_put_wq);
	146	}
	147	}
	148
	149	static void pblk_end_user_read(struct bio *bio)
	150	{
	151	#ifdef CONFIG_NVM_DEBUG
	152	WARN_ONCE(bio->bi_status, "pblk: corrupted read bio\n");
	153	#endif
	154	bio_endio(bio);
	155	bio_put(bio);
	156	}
	157
	158	static void __pblk_end_io_read(struct pblk pblk, struct nvm_rq rqd,
	159	bool put_line)
a4bd217b	160	{
084ec9ba	161	struct pblk_g_ctx *r_ctx = nvm_rq_to_pdu(rqd);
a4bd217b JG	162	struct bio *bio = rqd->bio;
	163
	164	if (rqd->error)
	165	pblk_log_read_err(pblk, rqd);
	166	#ifdef CONFIG_NVM_DEBUG
	167	else
4e4cbee9	168	WARN_ONCE(bio->bi_status, "pblk: corrupted read error\n");
a4bd217b JG	169	#endif
a4bd217b JG	170
a4809fee JG	171	pblk_read_check(pblk, rqd, r_ctx->lba);
a4809fee JG	172
a4bd217b	173	bio_put(bio);
7bd4d370 JG	174	if (r_ctx->private)
7bd4d370 JG	175	pblk_end_user_read((struct bio *)r_ctx->private);
084ec9ba	176
7bd4d370 JG	177	if (put_line)
7bd4d370 JG	178	pblk_read_put_rqd_kref(pblk, rqd);
a4bd217b JG	179
	180	#ifdef CONFIG_NVM_DEBUG
	181	atomic_long_add(rqd->nr_ppas, &pblk->sync_reads);
	182	atomic_long_sub(rqd->nr_ppas, &pblk->inflight_reads);
	183	#endif
	184
e2cddf20	185	pblk_free_rqd(pblk, rqd, PBLK_READ);
588726d3	186	atomic_dec(&pblk->inflight_io);
a4bd217b JG	187	}
a4bd217b JG	188
7bd4d370 JG	189	static void pblk_end_io_read(struct nvm_rq *rqd)
	190	{
	191	struct pblk *pblk = rqd->private;
	192
	193	__pblk_end_io_read(pblk, rqd, true);
	194	}
	195
a4bd217b JG	196	static int pblk_fill_partial_read_bio(struct pblk pblk, struct nvm_rq rqd,
	197	unsigned int bio_init_idx,
	198	unsigned long *read_bitmap)
	199	{
	200	struct bio new_bio, bio = rqd->bio;
a4809fee	201	struct pblk_sec_meta *meta_list = rqd->meta_list;
a4bd217b JG	202	struct bio_vec src_bv, dst_bv;
	203	void *ppa_ptr = NULL;
	204	void src_p, dst_p;
	205	dma_addr_t dma_ppa_list = 0;
a4809fee	206	__le64 lba_list_mem, lba_list_media;
a4bd217b JG	207	int nr_secs = rqd->nr_ppas;
	208	int nr_holes = nr_secs - bitmap_weight(read_bitmap, nr_secs);
	209	int i, ret, hole;
	210	DECLARE_COMPLETION_ONSTACK(wait);
	211
a4809fee JG	212	/* Re-use allocated memory for intermediate lbas */
	213	lba_list_mem = (((void *)rqd->ppa_list) + pblk_dma_ppa_size);
	214	lba_list_media = (((void )rqd->ppa_list) + 2 pblk_dma_ppa_size);
	215
a4bd217b	216	new_bio = bio_alloc(GFP_KERNEL, nr_holes);
a4bd217b JG	217
	218	if (pblk_bio_add_pages(pblk, new_bio, GFP_KERNEL, nr_holes))
	219	goto err;
	220
	221	if (nr_holes != new_bio->bi_vcnt) {
	222	pr_err("pblk: malformed bio\n");
	223	goto err;
	224	}
	225
a4809fee JG	226	for (i = 0; i < nr_secs; i++)
	227	lba_list_mem[i] = meta_list[i].lba;
	228
a4bd217b JG	229	new_bio->bi_iter.bi_sector = 0; /* internal bio */
a4bd217b JG	230	bio_set_op_attrs(new_bio, REQ_OP_READ, 0);
a4bd217b JG	231
	232	rqd->bio = new_bio;
	233	rqd->nr_ppas = nr_holes;
f9c10152	234	rqd->flags = pblk_set_read_mode(pblk, PBLK_READ_RANDOM);
26532ee5 JG	235	rqd->end_io = pblk_end_io_sync;
26532ee5 JG	236	rqd->private = &wait;
a4bd217b JG	237
	238	if (unlikely(nr_secs > 1 && nr_holes == 1)) {
	239	ppa_ptr = rqd->ppa_list;
	240	dma_ppa_list = rqd->dma_ppa_list;
	241	rqd->ppa_addr = rqd->ppa_list[0];
	242	}
	243
	244	ret = pblk_submit_read_io(pblk, rqd);
	245	if (ret) {
	246	bio_put(rqd->bio);
	247	pr_err("pblk: read IO submission failed\n");
	248	goto err;
	249	}
	250
	251	if (!wait_for_completion_io_timeout(&wait,
	252	msecs_to_jiffies(PBLK_COMMAND_TIMEOUT_MS))) {
	253	pr_err("pblk: partial read I/O timed out\n");
	254	}
	255
	256	if (rqd->error) {
	257	atomic_long_inc(&pblk->read_failed);
	258	#ifdef CONFIG_NVM_DEBUG
	259	pblk_print_failed_rqd(pblk, rqd, rqd->error);
	260	#endif
	261	}
	262
	263	if (unlikely(nr_secs > 1 && nr_holes == 1)) {
7bd4d370 JG	264	struct ppa_addr ppa;
	265
	266	ppa = rqd->ppa_addr;
a4bd217b JG	267	rqd->ppa_list = ppa_ptr;
a4bd217b JG	268	rqd->dma_ppa_list = dma_ppa_list;
7bd4d370	269	rqd->ppa_list[0] = ppa;
a4bd217b JG	270	}
a4bd217b JG	271
a4809fee JG	272	for (i = 0; i < nr_secs; i++) {
	273	lba_list_media[i] = meta_list[i].lba;
	274	meta_list[i].lba = lba_list_mem[i];
	275	}
	276
a4bd217b JG	277	/* Fill the holes in the original bio */
	278	i = 0;
	279	hole = find_first_zero_bit(read_bitmap, nr_secs);
	280	do {
7bd4d370 JG	281	int line_id = pblk_dev_ppa_to_line(rqd->ppa_list[i]);
	282	struct pblk_line *line = &pblk->lines[line_id];
	283
	284	kref_put(&line->ref, pblk_line_put);
	285
a4809fee JG	286	meta_list[hole].lba = lba_list_media[i];
a4809fee JG	287
a4bd217b JG	288	src_bv = new_bio->bi_io_vec[i++];
	289	dst_bv = bio->bi_io_vec[bio_init_idx + hole];
	290
	291	src_p = kmap_atomic(src_bv.bv_page);
	292	dst_p = kmap_atomic(dst_bv.bv_page);
	293
	294	memcpy(dst_p + dst_bv.bv_offset,
	295	src_p + src_bv.bv_offset,
	296	PBLK_EXPOSED_PAGE_SIZE);
	297
	298	kunmap_atomic(src_p);
	299	kunmap_atomic(dst_p);
	300
bd432417	301	mempool_free(src_bv.bv_page, pblk->page_bio_pool);
a4bd217b JG	302
	303	hole = find_next_zero_bit(read_bitmap, nr_secs, hole + 1);
	304	} while (hole < nr_secs);
	305
	306	bio_put(new_bio);
	307
	308	/* Complete the original bio and associated request */
7bd4d370	309	bio_endio(bio);
a4bd217b JG	310	rqd->bio = bio;
a4bd217b JG	311	rqd->nr_ppas = nr_secs;
a4bd217b	312
7bd4d370	313	__pblk_end_io_read(pblk, rqd, false);
a4bd217b JG	314	return NVM_IO_OK;
	315
	316	err:
	317	/* Free allocated pages in new bio */
	318	pblk_bio_free_pages(pblk, bio, 0, new_bio->bi_vcnt);
7bd4d370	319	__pblk_end_io_read(pblk, rqd, false);
a4bd217b JG	320	return NVM_IO_ERR;
	321	}
	322
	323	static void pblk_read_rq(struct pblk pblk, struct nvm_rq rqd,
84454e6d	324	sector_t lba, unsigned long *read_bitmap)
a4bd217b	325	{
a4809fee	326	struct pblk_sec_meta *meta_list = rqd->meta_list;
a4bd217b JG	327	struct bio *bio = rqd->bio;
a4bd217b JG	328	struct ppa_addr ppa;
a4bd217b JG	329
	330	pblk_lookup_l2p_seq(pblk, &ppa, lba, 1);
	331
	332	#ifdef CONFIG_NVM_DEBUG
	333	atomic_long_inc(&pblk->inflight_reads);
	334	#endif
	335
	336	retry:
	337	if (pblk_ppa_empty(ppa)) {
	338	WARN_ON(test_and_set_bit(0, read_bitmap));
a4809fee	339	meta_list[0].lba = cpu_to_le64(ADDR_EMPTY);
a4bd217b JG	340	return;
	341	}
	342
	343	/* Try to read from write buffer. The address is later checked on the
	344	* write buffer to prevent retrieving overwritten data.
	345	*/
	346	if (pblk_addr_in_cache(ppa)) {
75cb8e93	347	if (!pblk_read_from_cache(pblk, bio, lba, ppa, 0, 1)) {
a4bd217b JG	348	pblk_lookup_l2p_seq(pblk, &ppa, lba, 1);
	349	goto retry;
	350	}
a4809fee	351
7bd4d370	352	WARN_ON(test_and_set_bit(0, read_bitmap));
a4809fee JG	353	meta_list[0].lba = cpu_to_le64(lba);
a4809fee JG	354
db7ada33	355	#ifdef CONFIG_NVM_DEBUG
7bd4d370	356	atomic_long_inc(&pblk->cache_reads);
db7ada33	357	#endif
a4bd217b JG	358	} else {
	359	rqd->ppa_addr = ppa;
	360	}
f9c10152 JG	361
f9c10152 JG	362	rqd->flags = pblk_set_read_mode(pblk, PBLK_READ_RANDOM);
a4bd217b JG	363	}
	364
	365	int pblk_submit_read(struct pblk pblk, struct bio bio)
	366	{
	367	struct nvm_tgt_dev *dev = pblk->dev;
84454e6d	368	sector_t blba = pblk_get_lba(bio);
5bf1e1ee	369	unsigned int nr_secs = pblk_get_secs(bio);
a4809fee	370	struct pblk_g_ctx *r_ctx;
a4bd217b	371	struct nvm_rq *rqd;
a4bd217b	372	unsigned int bio_init_idx;
a4809fee	373	unsigned long read_bitmap; /* Max 64 ppas per request */
a4bd217b JG	374	int ret = NVM_IO_ERR;
a4bd217b JG	375
84454e6d JG	376	/* logic error: lba out-of-bounds. Ignore read request */
	377	if (blba >= pblk->rl.nr_secs \|\| nr_secs > PBLK_MAX_REQ_ADDRS) {
	378	WARN(1, "pblk: read lba out of bounds (lba:%llu, nr:%d)\n",
	379	(unsigned long long)blba, nr_secs);
a4bd217b	380	return NVM_IO_ERR;
84454e6d	381	}
a4bd217b JG	382
	383	bitmap_zero(&read_bitmap, nr_secs);
	384
e2cddf20	385	rqd = pblk_alloc_rqd(pblk, PBLK_READ);
a4bd217b JG	386
	387	rqd->opcode = NVM_OP_PREAD;
	388	rqd->bio = bio;
	389	rqd->nr_ppas = nr_secs;
	390	rqd->private = pblk;
	391	rqd->end_io = pblk_end_io_read;
	392
a4809fee JG	393	r_ctx = nvm_rq_to_pdu(rqd);
	394	r_ctx->lba = blba;
	395
a4bd217b JG	396	/* Save the index for this bio's start. This is needed in case
	397	* we need to fill a partial read.
	398	*/
	399	bio_init_idx = pblk_get_bi_idx(bio);
	400
63e3809c JG	401	rqd->meta_list = nvm_dev_dma_alloc(dev->parent, GFP_KERNEL,
	402	&rqd->dma_meta_list);
	403	if (!rqd->meta_list) {
	404	pr_err("pblk: not able to allocate ppa list\n");
	405	goto fail_rqd_free;
	406	}
	407
a4bd217b	408	if (nr_secs > 1) {
63e3809c JG	409	rqd->ppa_list = rqd->meta_list + pblk_dma_meta_size;
63e3809c JG	410	rqd->dma_ppa_list = rqd->dma_meta_list + pblk_dma_meta_size;
a4bd217b	411
84454e6d	412	pblk_read_ppalist_rq(pblk, rqd, blba, &read_bitmap);
a4bd217b	413	} else {
84454e6d	414	pblk_read_rq(pblk, rqd, blba, &read_bitmap);
a4bd217b JG	415	}
	416
	417	bio_get(bio);
	418	if (bitmap_full(&read_bitmap, nr_secs)) {
	419	bio_endio(bio);
588726d3	420	atomic_inc(&pblk->inflight_io);
7bd4d370	421	__pblk_end_io_read(pblk, rqd, false);
a4bd217b JG	422	return NVM_IO_OK;
	423	}
	424
	425	/* All sectors are to be read from the device */
	426	if (bitmap_empty(&read_bitmap, rqd->nr_ppas)) {
	427	struct bio *int_bio = NULL;
a4bd217b JG	428
a4bd217b JG	429	/* Clone read bio to deal with read errors internally */
b25d5237	430	int_bio = bio_clone_fast(bio, GFP_KERNEL, pblk_bio_set);
a4bd217b JG	431	if (!int_bio) {
	432	pr_err("pblk: could not clone read bio\n");
	433	return NVM_IO_ERR;
	434	}
	435
	436	rqd->bio = int_bio;
084ec9ba	437	r_ctx->private = bio;
a4bd217b JG	438
	439	ret = pblk_submit_read_io(pblk, rqd);
	440	if (ret) {
	441	pr_err("pblk: read IO submission failed\n");
	442	if (int_bio)
	443	bio_put(int_bio);
	444	return ret;
	445	}
	446
	447	return NVM_IO_OK;
	448	}
	449
	450	/* The read bio request could be partially filled by the write buffer,
	451	* but there are some holes that need to be read from the drive.
	452	*/
	453	ret = pblk_fill_partial_read_bio(pblk, rqd, bio_init_idx, &read_bitmap);
	454	if (ret) {
	455	pr_err("pblk: failed to perform partial read\n");
	456	return ret;
	457	}
	458
	459	return NVM_IO_OK;
	460
	461	fail_rqd_free:
e2cddf20	462	pblk_free_rqd(pblk, rqd, PBLK_READ);
a4bd217b JG	463	return ret;
	464	}
	465
	466	static int read_ppalist_rq_gc(struct pblk pblk, struct nvm_rq rqd,
	467	struct pblk_line line, u64 lba_list,
d340121e	468	u64 *paddr_list_gc, unsigned int nr_secs)
a4bd217b	469	{
d340121e JG	470	struct ppa_addr ppa_list_l2p[PBLK_MAX_REQ_ADDRS];
d340121e JG	471	struct ppa_addr ppa_gc;
a4bd217b JG	472	int valid_secs = 0;
	473	int i;
	474
d340121e	475	pblk_lookup_l2p_rand(pblk, ppa_list_l2p, lba_list, nr_secs);
a4bd217b JG	476
a4bd217b JG	477	for (i = 0; i < nr_secs; i++) {
d340121e JG	478	if (lba_list[i] == ADDR_EMPTY)
	479	continue;
	480
	481	ppa_gc = addr_to_gen_ppa(pblk, paddr_list_gc[i], line->id);
	482	if (!pblk_ppa_comp(ppa_list_l2p[i], ppa_gc)) {
	483	paddr_list_gc[i] = lba_list[i] = ADDR_EMPTY;
a4bd217b JG	484	continue;
	485	}
	486
d340121e	487	rqd->ppa_list[valid_secs++] = ppa_list_l2p[i];
a4bd217b JG	488	}
	489
	490	#ifdef CONFIG_NVM_DEBUG
	491	atomic_long_add(valid_secs, &pblk->inflight_reads);
	492	#endif
d340121e	493
a4bd217b JG	494	return valid_secs;
	495	}
	496
	497	static int read_rq_gc(struct pblk pblk, struct nvm_rq rqd,
d340121e JG	498	struct pblk_line *line, sector_t lba,
d340121e JG	499	u64 paddr_gc)
a4bd217b	500	{
d340121e	501	struct ppa_addr ppa_l2p, ppa_gc;
a4bd217b JG	502	int valid_secs = 0;
a4bd217b JG	503
659226eb DC	504	if (lba == ADDR_EMPTY)
	505	goto out;
	506
a4bd217b	507	/* logic error: lba out-of-bounds */
2a79efd8 DC	508	if (lba >= pblk->rl.nr_secs) {
2a79efd8 DC	509	WARN(1, "pblk: read lba out of bounds\n");
a4bd217b JG	510	goto out;
	511	}
	512
a4bd217b	513	spin_lock(&pblk->trans_lock);
d340121e	514	ppa_l2p = pblk_trans_map_get(pblk, lba);
a4bd217b JG	515	spin_unlock(&pblk->trans_lock);
a4bd217b JG	516
d340121e JG	517	ppa_gc = addr_to_gen_ppa(pblk, paddr_gc, line->id);
d340121e JG	518	if (!pblk_ppa_comp(ppa_l2p, ppa_gc))
a4bd217b JG	519	goto out;
a4bd217b JG	520
d340121e	521	rqd->ppa_addr = ppa_l2p;
a4bd217b JG	522	valid_secs = 1;
	523
	524	#ifdef CONFIG_NVM_DEBUG
	525	atomic_long_inc(&pblk->inflight_reads);
	526	#endif
	527
	528	out:
	529	return valid_secs;
	530	}
	531
d340121e	532	int pblk_submit_read_gc(struct pblk pblk, struct pblk_gc_rq gc_rq)
a4bd217b JG	533	{
	534	struct nvm_tgt_dev *dev = pblk->dev;
	535	struct nvm_geo *geo = &dev->geo;
a4bd217b JG	536	struct bio *bio;
a4bd217b JG	537	struct nvm_rq rqd;
d340121e JG	538	int data_len;
d340121e JG	539	int ret = NVM_IO_OK;
a4bd217b JG	540	DECLARE_COMPLETION_ONSTACK(wait);
	541
	542	memset(&rqd, 0, sizeof(struct nvm_rq));
	543
63e3809c JG	544	rqd.meta_list = nvm_dev_dma_alloc(dev->parent, GFP_KERNEL,
	545	&rqd.dma_meta_list);
	546	if (!rqd.meta_list)
d340121e	547	return -ENOMEM;
63e3809c	548
d340121e	549	if (gc_rq->nr_secs > 1) {
63e3809c JG	550	rqd.ppa_list = rqd.meta_list + pblk_dma_meta_size;
63e3809c JG	551	rqd.dma_ppa_list = rqd.dma_meta_list + pblk_dma_meta_size;
a4bd217b	552
d340121e JG	553	gc_rq->secs_to_gc = read_ppalist_rq_gc(pblk, &rqd, gc_rq->line,
	554	gc_rq->lba_list,
	555	gc_rq->paddr_list,
	556	gc_rq->nr_secs);
	557	if (gc_rq->secs_to_gc == 1)
63e3809c	558	rqd.ppa_addr = rqd.ppa_list[0];
a4bd217b	559	} else {
d340121e JG	560	gc_rq->secs_to_gc = read_rq_gc(pblk, &rqd, gc_rq->line,
	561	gc_rq->lba_list[0],
	562	gc_rq->paddr_list[0]);
a4bd217b JG	563	}
a4bd217b JG	564
d340121e	565	if (!(gc_rq->secs_to_gc))
a4bd217b JG	566	goto out;
a4bd217b JG	567
d340121e JG	568	data_len = (gc_rq->secs_to_gc) * geo->sec_size;
d340121e JG	569	bio = pblk_bio_map_addr(pblk, gc_rq->data, gc_rq->secs_to_gc, data_len,
7d327a9e	570	PBLK_VMALLOC_META, GFP_KERNEL);
a4bd217b JG	571	if (IS_ERR(bio)) {
	572	pr_err("pblk: could not allocate GC bio (%lu)\n", PTR_ERR(bio));
	573	goto err_free_dma;
	574	}
	575
	576	bio->bi_iter.bi_sector = 0; /* internal bio */
	577	bio_set_op_attrs(bio, REQ_OP_READ, 0);
	578
	579	rqd.opcode = NVM_OP_PREAD;
	580	rqd.end_io = pblk_end_io_sync;
	581	rqd.private = &wait;
d340121e	582	rqd.nr_ppas = gc_rq->secs_to_gc;
f9c10152	583	rqd.flags = pblk_set_read_mode(pblk, PBLK_READ_RANDOM);
a4bd217b JG	584	rqd.bio = bio;
a4bd217b JG	585
d340121e JG	586	if (pblk_submit_read_io(pblk, &rqd)) {
d340121e JG	587	ret = -EIO;
a4bd217b	588	pr_err("pblk: GC read request failed\n");
7d327a9e	589	goto err_free_bio;
a4bd217b JG	590	}
	591
	592	if (!wait_for_completion_io_timeout(&wait,
	593	msecs_to_jiffies(PBLK_COMMAND_TIMEOUT_MS))) {
	594	pr_err("pblk: GC read I/O timed out\n");
	595	}
588726d3	596	atomic_dec(&pblk->inflight_io);
a4bd217b JG	597
	598	if (rqd.error) {
	599	atomic_long_inc(&pblk->read_failed_gc);
	600	#ifdef CONFIG_NVM_DEBUG
	601	pblk_print_failed_rqd(pblk, &rqd, rqd.error);
	602	#endif
	603	}
	604
	605	#ifdef CONFIG_NVM_DEBUG
d340121e JG	606	atomic_long_add(gc_rq->secs_to_gc, &pblk->sync_reads);
	607	atomic_long_add(gc_rq->secs_to_gc, &pblk->recov_gc_reads);
	608	atomic_long_sub(gc_rq->secs_to_gc, &pblk->inflight_reads);
a4bd217b JG	609	#endif
	610
	611	out:
63e3809c	612	nvm_dev_dma_free(dev->parent, rqd.meta_list, rqd.dma_meta_list);
d340121e	613	return ret;
a4bd217b	614
7d327a9e JG	615	err_free_bio:
7d327a9e JG	616	bio_put(bio);
a4bd217b	617	err_free_dma:
63e3809c	618	nvm_dev_dma_free(dev->parent, rqd.meta_list, rqd.dma_meta_list);
d340121e	619	return ret;
a4bd217b	620	}