diff --git a/include/spdk/bdev_module.h b/include/spdk/bdev_module.h
index 568e5b85a..a946aa86b 100644
--- a/include/spdk/bdev_module.h
+++ b/include/spdk/bdev_module.h
@@ -616,9 +616,8 @@ void spdk_bdev_io_get_buf(struct spdk_bdev_io *bdev_io, spdk_bdev_io_get_buf_cb
  * \param buf The buffer to set as the active data buffer.
  * \param len The length of the buffer.
  *
- * \return The usable size of the buffer, after adjustments of alignment.
  */
-size_t spdk_bdev_io_set_buf(struct spdk_bdev_io *bdev_io, void *buf, size_t len);
+void spdk_bdev_io_set_buf(struct spdk_bdev_io *bdev_io, void *buf, size_t len);
 
 /**
  * Complete a bdev_io
diff --git a/lib/bdev/bdev.c b/lib/bdev/bdev.c
index 44a25d515..ae3f9e742 100644
--- a/lib/bdev/bdev.c
+++ b/lib/bdev/bdev.c
@@ -377,33 +377,18 @@ spdk_bdev_get_by_name(const char *bdev_name)
 	return NULL;
 }
 
-size_t
+void
 spdk_bdev_io_set_buf(struct spdk_bdev_io *bdev_io, void *buf, size_t len)
 {
-	struct iovec **iovs;
-	int *iovcnt;
-	void *aligned_buf;
+	struct iovec *iovs;
 
-	iovs = &bdev_io->u.bdev.iovs;
-	iovcnt = &bdev_io->u.bdev.iovcnt;
+	iovs = bdev_io->u.bdev.iovs;
 
-	if (*iovs == NULL || *iovcnt == 0) {
-		*iovs = &bdev_io->iov;
-		*iovcnt = 1;
-	}
+	assert(iovs != NULL);
+	assert(bdev_io->u.bdev.iovcnt >= 1);
 
-	if (buf != NULL) {
-		aligned_buf = (void *)(((uintptr_t)buf + 511) & ~511UL);
-		len = len - ((uintptr_t)aligned_buf - (uintptr_t)buf);
-	} else {
-		aligned_buf = NULL;
-		assert(len == 0);
-	}
-
-	(*iovs)[0].iov_base = aligned_buf;
-	(*iovs)[0].iov_len = len;
-
-	return len;
+	iovs[0].iov_base = buf;
+	iovs[0].iov_len = len;
 }
 
 static void
@@ -411,38 +396,34 @@ spdk_bdev_io_put_buf(struct spdk_bdev_io *bdev_io)
 {
 	struct spdk_mempool *pool;
 	struct spdk_bdev_io *tmp;
-	void *buf;
+	void *buf, *aligned_buf;
 	bdev_io_stailq_t *stailq;
 	struct spdk_bdev_mgmt_channel *ch;
-	size_t len;
 
 	assert(bdev_io->u.bdev.iovcnt == 1);
 
 	buf = bdev_io->internal.buf;
 	ch = bdev_io->internal.ch->shared_resource->mgmt_ch;
 
+	bdev_io->internal.buf = NULL;
+
 	if (bdev_io->internal.buf_len <= SPDK_BDEV_SMALL_BUF_MAX_SIZE) {
 		pool = g_bdev_mgr.buf_small_pool;
 		stailq = &ch->need_buf_small;
-		len = SPDK_BDEV_SMALL_BUF_MAX_SIZE + 512;
 	} else {
 		pool = g_bdev_mgr.buf_large_pool;
 		stailq = &ch->need_buf_large;
-		len = SPDK_BDEV_LARGE_BUF_MAX_SIZE + 512;
 	}
 
 	if (STAILQ_EMPTY(stailq)) {
 		spdk_mempool_put(pool, buf);
 	} else {
 		tmp = STAILQ_FIRST(stailq);
+
+		aligned_buf = (void *)(((uintptr_t)buf + 511) & ~511UL);
+		spdk_bdev_io_set_buf(bdev_io, aligned_buf, tmp->internal.buf_len);
+
 		STAILQ_REMOVE_HEAD(stailq, internal.buf_link);
-		len = spdk_bdev_io_set_buf(tmp, buf, len);
-		if (len < tmp->internal.buf_len) {
-			SPDK_ERRLOG("Unable to use buffer due to alignment\n");
-			spdk_mempool_put(pool, buf);
-			spdk_bdev_io_set_buf(tmp, NULL, 0);
-			return;
-		}
 		tmp->internal.buf = buf;
 		tmp->internal.get_buf_cb(tmp->internal.ch->channel, tmp);
 	}
@@ -453,9 +434,8 @@ spdk_bdev_io_get_buf(struct spdk_bdev_io *bdev_io, spdk_bdev_io_get_buf_cb cb, u
 {
 	struct spdk_mempool *pool;
 	bdev_io_stailq_t *stailq;
-	void *buf = NULL;
+	void *buf, *aligned_buf;
 	struct spdk_bdev_mgmt_channel *mgmt_ch;
-	size_t buf_len;
 
 	assert(cb != NULL);
 	assert(bdev_io->u.bdev.iovs != NULL);
@@ -474,11 +454,9 @@ spdk_bdev_io_get_buf(struct spdk_bdev_io *bdev_io, spdk_bdev_io_get_buf_cb cb, u
 	if (len <= SPDK_BDEV_SMALL_BUF_MAX_SIZE) {
 		pool = g_bdev_mgr.buf_small_pool;
 		stailq = &mgmt_ch->need_buf_small;
-		buf_len = SPDK_BDEV_SMALL_BUF_MAX_SIZE + 512;
 	} else {
 		pool = g_bdev_mgr.buf_large_pool;
 		stailq = &mgmt_ch->need_buf_large;
-		buf_len = SPDK_BDEV_LARGE_BUF_MAX_SIZE + 512;
 	}
 
 	buf = spdk_mempool_get(pool);
@@ -486,16 +464,8 @@ spdk_bdev_io_get_buf(struct spdk_bdev_io *bdev_io, spdk_bdev_io_get_buf_cb cb, u
 	if (!buf) {
 		STAILQ_INSERT_TAIL(stailq, bdev_io, internal.buf_link);
 	} else {
-		size_t aligned_len;
-
-		aligned_len = spdk_bdev_io_set_buf(bdev_io, buf, buf_len);
-		if (aligned_len < len) {
-			SPDK_ERRLOG("Unable to use buffer after alignment calculations.\n");
-			spdk_mempool_put(pool, buf);
-			spdk_bdev_io_set_buf(bdev_io, NULL, 0);
-			STAILQ_INSERT_TAIL(stailq, bdev_io, internal.buf_link);
-			return;
-		}
+		aligned_buf = (void *)(((uintptr_t)buf + 511) & ~511UL);
+		spdk_bdev_io_set_buf(bdev_io, aligned_buf, len);
 
 		bdev_io->internal.buf = buf;
 		bdev_io->internal.get_buf_cb(bdev_io->internal.ch->channel, bdev_io);