diff --git a/drivers/lightnvm/pblk-core.c b/drivers/lightnvm/pblk-core.c
index a654b34f6f86466deb90334ef46ad34458a40f36..74b8d9db05e19767bf7c94c8ddb2794605c25ae4 100644
--- a/drivers/lightnvm/pblk-core.c
+++ b/drivers/lightnvm/pblk-core.c
@@ -425,16 +425,15 @@ int pblk_submit_io(struct pblk *pblk, struct nvm_rq *rqd)
 
 struct bio *pblk_bio_map_addr(struct pblk *pblk, void *data,
 			      unsigned int nr_secs, unsigned int len,
-			      gfp_t gfp_mask)
+			      int alloc_type, gfp_t gfp_mask)
 {
 	struct nvm_tgt_dev *dev = pblk->dev;
-	struct pblk_line_mgmt *l_mg = &pblk->l_mg;
 	void *kaddr = data;
 	struct page *page;
 	struct bio *bio;
 	int i, ret;
 
-	if (l_mg->emeta_alloc_type == PBLK_KMALLOC_META)
+	if (alloc_type == PBLK_KMALLOC_META)
 		return bio_map_kern(dev->q, kaddr, len, gfp_mask);
 
 	bio = bio_kmalloc(gfp_mask, nr_secs);
@@ -552,6 +551,7 @@ static int pblk_line_submit_emeta_io(struct pblk *pblk, struct pblk_line *line,
 {
 	struct nvm_tgt_dev *dev = pblk->dev;
 	struct nvm_geo *geo = &dev->geo;
+	struct pblk_line_mgmt *l_mg = &pblk->l_mg;
 	struct pblk_line_meta *lm = &pblk->lm;
 	void *ppa_list, *meta_list;
 	struct bio *bio;
@@ -589,7 +589,8 @@ static int pblk_line_submit_emeta_io(struct pblk *pblk, struct pblk_line *line,
 	rq_ppas = pblk_calc_secs(pblk, left_ppas, 0);
 	rq_len = rq_ppas * geo->sec_size;
 
-	bio = pblk_bio_map_addr(pblk, emeta_buf, rq_ppas, rq_len, GFP_KERNEL);
+	bio = pblk_bio_map_addr(pblk, emeta_buf, rq_ppas, rq_len,
+					l_mg->emeta_alloc_type, GFP_KERNEL);
 	if (IS_ERR(bio)) {
 		ret = PTR_ERR(bio);
 		goto free_rqd_dma;
diff --git a/drivers/lightnvm/pblk-gc.c b/drivers/lightnvm/pblk-gc.c
index 9b4059b93855d702f956a3ec4e0a46fd849141a5..6090d28f7995a51f4d5972bf965457f1388874f7 100644
--- a/drivers/lightnvm/pblk-gc.c
+++ b/drivers/lightnvm/pblk-gc.c
@@ -20,7 +20,7 @@
 
 static void pblk_gc_free_gc_rq(struct pblk_gc_rq *gc_rq)
 {
-	kfree(gc_rq->data);
+	vfree(gc_rq->data);
 	kfree(gc_rq);
 }
 
@@ -72,7 +72,7 @@ static int pblk_gc_move_valid_secs(struct pblk *pblk, struct pblk_gc_rq *gc_rq)
 	unsigned int secs_to_gc;
 	int ret = 0;
 
-	data = kmalloc(gc_rq->nr_secs * geo->sec_size, GFP_KERNEL);
+	data = vmalloc(gc_rq->nr_secs * geo->sec_size);
 	if (!data) {
 		ret = -ENOMEM;
 		goto out;
@@ -110,7 +110,7 @@ static int pblk_gc_move_valid_secs(struct pblk *pblk, struct pblk_gc_rq *gc_rq)
 free_rq:
 	kfree(gc_rq);
 free_data:
-	kfree(data);
+	vfree(data);
 out:
 	kref_put(&line->ref, pblk_line_put);
 	return ret;
diff --git a/drivers/lightnvm/pblk-read.c b/drivers/lightnvm/pblk-read.c
index ed2ea01a0a3864fcf98b0f63dca5dde4906dac66..31d4869b05008a201c8df45a713fd82c5fc704b3 100644
--- a/drivers/lightnvm/pblk-read.c
+++ b/drivers/lightnvm/pblk-read.c
@@ -462,7 +462,6 @@ int pblk_submit_read_gc(struct pblk *pblk, u64 *lba_list, void *data,
 {
 	struct nvm_tgt_dev *dev = pblk->dev;
 	struct nvm_geo *geo = &dev->geo;
-	struct request_queue *q = dev->q;
 	struct bio *bio;
 	struct nvm_rq rqd;
 	int ret, data_len;
@@ -491,7 +490,8 @@ int pblk_submit_read_gc(struct pblk *pblk, u64 *lba_list, void *data,
 		goto out;
 
 	data_len = (*secs_to_gc) * geo->sec_size;
-	bio = bio_map_kern(q, data, data_len, GFP_KERNEL);
+	bio = pblk_bio_map_addr(pblk, data, *secs_to_gc, data_len,
+						PBLK_KMALLOC_META, GFP_KERNEL);
 	if (IS_ERR(bio)) {
 		pr_err("pblk: could not allocate GC bio (%lu)\n", PTR_ERR(bio));
 		goto err_free_dma;
diff --git a/drivers/lightnvm/pblk-write.c b/drivers/lightnvm/pblk-write.c
index 3e0b84937b90039d8d6557e6870a60e8ae70dd0b..8151bf4bb945b7b86b52c13785fc1ebdf85a121e 100644
--- a/drivers/lightnvm/pblk-write.c
+++ b/drivers/lightnvm/pblk-write.c
@@ -389,7 +389,8 @@ int pblk_submit_meta_io(struct pblk *pblk, struct pblk_line *meta_line)
 	rq_len = rq_ppas * geo->sec_size;
 	data = ((void *)emeta->buf) + emeta->mem;
 
-	bio = pblk_bio_map_addr(pblk, data, rq_ppas, rq_len, GFP_KERNEL);
+	bio = pblk_bio_map_addr(pblk, data, rq_ppas, rq_len,
+					l_mg->emeta_alloc_type, GFP_KERNEL);
 	if (IS_ERR(bio)) {
 		ret = PTR_ERR(bio);
 		goto fail_free_rqd;
diff --git a/drivers/lightnvm/pblk.h b/drivers/lightnvm/pblk.h
index 36c5f5999324f8c2e7081c96fed726ea6a217cd1..cdad2c9edbdf86dcf8099d09d529d2ecf247f293 100644
--- a/drivers/lightnvm/pblk.h
+++ b/drivers/lightnvm/pblk.h
@@ -698,7 +698,7 @@ int pblk_submit_io(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,
-			      gfp_t gfp_mask);
+			      int alloc_type, gfp_t gfp_mask);
 struct pblk_line *pblk_line_get(struct pblk *pblk);
 struct pblk_line *pblk_line_get_first_data(struct pblk *pblk);
 void pblk_line_replace_data(struct pblk *pblk);
@@ -805,7 +805,7 @@ int pblk_recov_setup_rq(struct pblk *pblk, struct pblk_c_ctx *c_ctx,
  * pblk gc
  */
 #define PBLK_GC_MAX_READERS 8	/* Max number of outstanding GC reader jobs */
-#define PBLK_GC_W_QD 1024	/* Queue depth for inflight GC write I/Os */
+#define PBLK_GC_W_QD 128	/* Queue depth for inflight GC write I/Os */
 #define PBLK_GC_L_QD 4		/* Queue depth for inflight GC lines */
 #define PBLK_GC_RSV_LINE 1	/* Reserved lines for GC */