diff mbox

[v5,3/3] mmc: card: Add eMMC4.5 write packed commands unit-tests

Message ID 1343744710-31700-4-git-send-email-merez@codeaurora.org (mailing list archive)
State New, archived
Headers show

Commit Message

Maya Erez July 31, 2012, 2:25 p.m. UTC
Expose the following packed commands tests:
- Test the write packed commands list preparation
- Simulate a returned error code
- Send an invalid packed command to the card

Signed-off-by: Lee Susman <lsusman@codeaurora.org>
Signed-off-by: Maya Erez <merez@codeaurora.org>
---
 drivers/mmc/card/Kconfig          |   11 +
 drivers/mmc/card/Makefile         |    1 +
 drivers/mmc/card/block.c          |   82 ++-
 drivers/mmc/card/mmc_block_test.c | 1522 +++++++++++++++++++++++++++++++++++++
 drivers/mmc/card/queue.h          |   15 +
 5 files changed, 1619 insertions(+), 12 deletions(-)
 create mode 100644 drivers/mmc/card/mmc_block_test.c
diff mbox

Patch

diff --git a/drivers/mmc/card/Kconfig b/drivers/mmc/card/Kconfig
index 3b1f783..bbe8cac 100644
--- a/drivers/mmc/card/Kconfig
+++ b/drivers/mmc/card/Kconfig
@@ -67,3 +67,14 @@  config MMC_TEST
 
 	  This driver is only of interest to those developing or
 	  testing a host driver. Most people should say N here.
+
+config MMC_BLOCK_TEST
+	tristate "MMC block test"
+	depends on MMC_BLOCK && IOSCHED_TEST
+	default m
+	help
+	  MMC block test can be used with test iosched to test the MMC block
+	  device.
+	  Currently used to test eMMC 4.5 features (packed commands, sanitize,
+	  BKOPs).
+
diff --git a/drivers/mmc/card/Makefile b/drivers/mmc/card/Makefile
index c73b406..d55107f 100644
--- a/drivers/mmc/card/Makefile
+++ b/drivers/mmc/card/Makefile
@@ -8,3 +8,4 @@  obj-$(CONFIG_MMC_TEST)		+= mmc_test.o
 
 obj-$(CONFIG_SDIO_UART)		+= sdio_uart.o
 
+obj-$(CONFIG_MMC_BLOCK_TEST)		+= mmc_block_test.o
diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c
index 92a6e25..e4239cc 100644
--- a/drivers/mmc/card/block.c
+++ b/drivers/mmc/card/block.c
@@ -123,17 +123,6 @@  struct mmc_blk_data {
 
 static DEFINE_MUTEX(open_lock);
 
-enum mmc_blk_status {
-	MMC_BLK_SUCCESS = 0,
-	MMC_BLK_PARTIAL,
-	MMC_BLK_CMD_ERR,
-	MMC_BLK_RETRY,
-	MMC_BLK_ABORT,
-	MMC_BLK_DATA_ERR,
-	MMC_BLK_ECC_ERR,
-	MMC_BLK_NOMEDIUM,
-};
-
 enum {
 	MMC_PACKED_N_IDX = -1,
 	MMC_PACKED_N_ZERO,
@@ -1330,6 +1319,64 @@  void mmc_blk_init_packed_statistics(struct mmc_card *card)
 }
 EXPORT_SYMBOL(mmc_blk_init_packed_statistics);
 
+void print_mmc_packing_stats(struct mmc_card *card)
+{
+	int i;
+	int max_num_of_packed_reqs = 0;
+
+	if ((!card) || (!card->wr_pack_stats.packing_events))
+		return;
+
+	max_num_of_packed_reqs = card->ext_csd.max_packed_writes;
+
+	spin_lock(&card->wr_pack_stats.lock);
+
+	pr_info("%s: write packing statistics:\n",
+		mmc_hostname(card->host));
+
+	for (i = 1 ; i <= max_num_of_packed_reqs ; ++i) {
+		if (card->wr_pack_stats.packing_events[i] != 0)
+			pr_info("%s: Packed %d reqs - %d times\n",
+				mmc_hostname(card->host), i,
+				card->wr_pack_stats.packing_events[i]);
+	}
+
+	pr_info("%s: stopped packing due to the following reasons:\n",
+		mmc_hostname(card->host));
+
+	if (card->wr_pack_stats.pack_stop_reason[EXCEEDS_SEGMENTS])
+		pr_info("%s: %d times: exceedmax num of segments\n",
+			mmc_hostname(card->host),
+			card->wr_pack_stats.pack_stop_reason[EXCEEDS_SEGMENTS]);
+	if (card->wr_pack_stats.pack_stop_reason[EXCEEDS_SECTORS])
+		pr_info("%s: %d times: exceeding the max num of sectors\n",
+			mmc_hostname(card->host),
+			card->wr_pack_stats.pack_stop_reason[EXCEEDS_SECTORS]);
+	if (card->wr_pack_stats.pack_stop_reason[WRONG_DATA_DIR])
+		pr_info("%s: %d times: wrong data direction\n",
+			mmc_hostname(card->host),
+			card->wr_pack_stats.pack_stop_reason[WRONG_DATA_DIR]);
+	if (card->wr_pack_stats.pack_stop_reason[FLUSH_OR_DISCARD])
+		pr_info("%s: %d times: flush or discard\n",
+			mmc_hostname(card->host),
+			card->wr_pack_stats.pack_stop_reason[FLUSH_OR_DISCARD]);
+	if (card->wr_pack_stats.pack_stop_reason[EMPTY_QUEUE])
+		pr_info("%s: %d times: empty queue\n",
+			mmc_hostname(card->host),
+			card->wr_pack_stats.pack_stop_reason[EMPTY_QUEUE]);
+	if (card->wr_pack_stats.pack_stop_reason[REL_WRITE])
+		pr_info("%s: %d times: rel write\n",
+			mmc_hostname(card->host),
+			card->wr_pack_stats.pack_stop_reason[REL_WRITE]);
+	if (card->wr_pack_stats.pack_stop_reason[THRESHOLD])
+		pr_info("%s: %d times: Threshold\n",
+			mmc_hostname(card->host),
+			card->wr_pack_stats.pack_stop_reason[THRESHOLD]);
+
+	spin_unlock(&card->wr_pack_stats.lock);
+}
+EXPORT_SYMBOL(print_mmc_packing_stats);
+
 static u8 mmc_blk_prep_packed_list(struct mmc_queue *mq, struct request *req)
 {
 	struct request_queue *q = mq->queue;
@@ -1539,7 +1586,18 @@  static void mmc_blk_packed_hdr_wrq_prep(struct mmc_queue_req *mqrq,
 	brq->data.sg_len = mmc_queue_map_sg(mq, mqrq);
 
 	mqrq->mmc_active.mrq = &brq->mrq;
-	mqrq->mmc_active.err_check = mmc_blk_packed_err_check;
+
+	/*
+	 * This is intended for packed commands tests usage - in case these
+	 * functions are not in use the respective pointers are NULL
+	 */
+	if (mq->err_check_fn)
+		mqrq->mmc_active.err_check = mq->err_check_fn;
+	else
+		mqrq->mmc_active.err_check = mmc_blk_packed_err_check;
+
+	if (mq->packed_test_fn)
+		mq->packed_test_fn(mq->queue, mqrq);
 
 	mmc_queue_bounce_pre(mqrq);
 }
diff --git a/drivers/mmc/card/mmc_block_test.c b/drivers/mmc/card/mmc_block_test.c
new file mode 100644
index 0000000..cb5e160
--- /dev/null
+++ b/drivers/mmc/card/mmc_block_test.c
@@ -0,0 +1,1522 @@ 
+
+/* Copyright (c) 2012, Code Aurora Forum. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only 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.
+ *
+ */
+
+/* MMC block test */
+
+#include <linux/module.h>
+#include <linux/blkdev.h>
+#include <linux/debugfs.h>
+#include <linux/mmc/card.h>
+#include <linux/mmc/host.h>
+#include <linux/delay.h>
+#include <linux/test-iosched.h>
+#include "queue.h"
+
+#define MODULE_NAME "mmc_block_test"
+#define TEST_MAX_SECTOR_RANGE		(600*1024*1024) /* 600 MB */
+#define TEST_MAX_BIOS_PER_REQ		120
+#define CMD23_PACKED_BIT	(1 << 30)
+#define LARGE_PRIME_1	1103515367
+#define LARGE_PRIME_2	35757
+#define PACKED_HDR_VER_MASK 0x000000FF
+#define PACKED_HDR_RW_MASK 0x0000FF00
+#define PACKED_HDR_NUM_REQS_MASK 0x00FF0000
+#define PACKED_HDR_BITS_16_TO_29_SET 0x3FFF0000
+
+#define test_pr_debug(fmt, args...) pr_debug("%s: "fmt"\n", MODULE_NAME, args)
+#define test_pr_info(fmt, args...) pr_info("%s: "fmt"\n", MODULE_NAME, args)
+#define test_pr_err(fmt, args...) pr_err("%s: "fmt"\n", MODULE_NAME, args)
+
+enum is_random {
+	NON_RANDOM_TEST,
+	RANDOM_TEST,
+};
+
+enum mmc_block_test_testcases {
+	/* Start of send write packing test group */
+	SEND_WRITE_PACKING_MIN_TESTCASE,
+	TEST_STOP_DUE_TO_READ = SEND_WRITE_PACKING_MIN_TESTCASE,
+	TEST_STOP_DUE_TO_READ_AFTER_MAX_REQS,
+	TEST_STOP_DUE_TO_FLUSH,
+	TEST_STOP_DUE_TO_FLUSH_AFTER_MAX_REQS,
+	TEST_STOP_DUE_TO_EMPTY_QUEUE,
+	TEST_STOP_DUE_TO_MAX_REQ_NUM,
+	TEST_STOP_DUE_TO_THRESHOLD,
+	SEND_WRITE_PACKING_MAX_TESTCASE = TEST_STOP_DUE_TO_THRESHOLD,
+
+	/* Start of err check test group */
+	ERR_CHECK_MIN_TESTCASE,
+	TEST_RET_ABORT = ERR_CHECK_MIN_TESTCASE,
+	TEST_RET_PARTIAL_FOLLOWED_BY_SUCCESS,
+	TEST_RET_PARTIAL_FOLLOWED_BY_ABORT,
+	TEST_RET_PARTIAL_MULTIPLE_UNTIL_SUCCESS,
+	TEST_RET_PARTIAL_MAX_FAIL_IDX,
+	TEST_RET_RETRY,
+	TEST_RET_CMD_ERR,
+	TEST_RET_DATA_ERR,
+	ERR_CHECK_MAX_TESTCASE = TEST_RET_DATA_ERR,
+
+	/* Start of send invalid test group */
+	INVALID_CMD_MIN_TESTCASE,
+	TEST_HDR_INVALID_VERSION = INVALID_CMD_MIN_TESTCASE,
+	TEST_HDR_WRONG_WRITE_CODE,
+	TEST_HDR_INVALID_RW_CODE,
+	TEST_HDR_DIFFERENT_ADDRESSES,
+	TEST_HDR_REQ_NUM_SMALLER_THAN_ACTUAL,
+	TEST_HDR_REQ_NUM_LARGER_THAN_ACTUAL,
+	TEST_HDR_CMD23_PACKED_BIT_SET,
+	TEST_CMD23_MAX_PACKED_WRITES,
+	TEST_CMD23_ZERO_PACKED_WRITES,
+	TEST_CMD23_PACKED_BIT_UNSET,
+	TEST_CMD23_REL_WR_BIT_SET,
+	TEST_CMD23_BITS_16TO29_SET,
+	TEST_CMD23_HDR_BLK_NOT_IN_COUNT,
+	INVALID_CMD_MAX_TESTCASE = TEST_CMD23_HDR_BLK_NOT_IN_COUNT,
+};
+
+enum mmc_block_test_group {
+	TEST_NO_GROUP,
+	TEST_GENERAL_GROUP,
+	TEST_SEND_WRITE_PACKING_GROUP,
+	TEST_ERR_CHECK_GROUP,
+	TEST_SEND_INVALID_GROUP,
+};
+
+struct mmc_block_test_debug {
+	struct dentry *send_write_packing_test;
+	struct dentry *err_check_test;
+	struct dentry *send_invalid_packed_test;
+	struct dentry *random_test_seed;
+};
+
+struct mmc_block_test_data {
+	/* The number of write requests that the test will issue */
+	int num_requests;
+	/* The expected write packing statistics for the current test */
+	struct mmc_wr_pack_stats exp_packed_stats;
+	/*
+	 * A user-defined seed for random choices of number of bios written in
+	 * a request, and of number of requests issued in a test
+	 * This field is randomly updated after each use
+	 */
+	unsigned int random_test_seed;
+	/* A retry counter used in err_check tests */
+	int err_check_counter;
+	/* Can be one of the values of enum test_group */
+	enum mmc_block_test_group test_group;
+	/*
+	 * Indicates if the current testcase is running with random values of
+	 * num_requests and num_bios (in each request)
+	 */
+	int is_random;
+	/* Data structure for debugfs dentrys */
+	struct mmc_block_test_debug debug;
+	/*
+	 * Data structure containing individual test information, including
+	 * self-defined specific data
+	 */
+	struct test_info test_info;
+	/* mmc block device test */
+	struct blk_dev_test_type bdt;
+};
+
+static struct mmc_block_test_data *mbtd;
+
+/*
+ * A callback assigned to the packed_test_fn field.
+ * Called from block layer in mmc_blk_packed_hdr_wrq_prep.
+ * Here we alter the packed header or CMD23 in order to send an invalid
+ * packed command to the card.
+ */
+static void test_invalid_packed_cmd(struct request_queue *q,
+				    struct mmc_queue_req *mqrq)
+{
+	struct mmc_queue *mq = q->queuedata;
+	u32 *packed_cmd_hdr = mqrq->packed_cmd_hdr;
+	struct request *req = mqrq->req;
+	struct request *second_rq;
+	struct test_request *test_rq;
+	struct mmc_blk_request *brq = &mqrq->brq;
+	int num_requests;
+	int max_packed_reqs;
+
+	if (!mq) {
+		test_pr_err("%s: NULL mq", __func__);
+		return;
+	}
+
+	test_rq = (struct test_request *)req->elv.priv[0];
+	if (!test_rq) {
+		test_pr_err("%s: NULL test_rq", __func__);
+		return;
+	}
+	max_packed_reqs = mq->card->ext_csd.max_packed_writes;
+
+	switch (mbtd->test_info.testcase) {
+	case TEST_HDR_INVALID_VERSION:
+		test_pr_info("%s: set invalid header version", __func__);
+		/* Put 0 in header version field (1 byte, offset 0 in header) */
+		packed_cmd_hdr[0] = packed_cmd_hdr[0] & ~PACKED_HDR_VER_MASK;
+		break;
+	case TEST_HDR_WRONG_WRITE_CODE:
+		test_pr_info("%s: wrong write code", __func__);
+		/* Set R/W field with R value (1 byte, offset 1 in header) */
+		packed_cmd_hdr[0] = packed_cmd_hdr[0] & ~PACKED_HDR_RW_MASK;
+		packed_cmd_hdr[0] = packed_cmd_hdr[0] | 0x00000100;
+		break;
+	case TEST_HDR_INVALID_RW_CODE:
+		test_pr_info("%s: invalid r/w code", __func__);
+		/* Set R/W field with invalid value */
+		packed_cmd_hdr[0] = packed_cmd_hdr[0] & ~PACKED_HDR_RW_MASK;
+		packed_cmd_hdr[0] = packed_cmd_hdr[0] | 0x00000400;
+		break;
+	case TEST_HDR_DIFFERENT_ADDRESSES:
+		test_pr_info("%s: different addresses", __func__);
+		second_rq = list_entry(req->queuelist.next, struct request,
+				queuelist);
+		test_pr_info("%s: test_rq->sector=%ld, second_rq->sector=%ld",
+			      __func__, (long)req->__sector,
+			     (long)second_rq->__sector);
+		/*
+		 * Put start sector of second write request in the first write
+		 * request's cmd25 argument in the packed header
+		 */
+		packed_cmd_hdr[3] = second_rq->__sector;
+		break;
+	case TEST_HDR_REQ_NUM_SMALLER_THAN_ACTUAL:
+		test_pr_info("%s: request num smaller than actual" , __func__);
+		num_requests = (packed_cmd_hdr[0] & PACKED_HDR_NUM_REQS_MASK)
+									>> 16;
+		/* num of entries is decremented by 1 */
+		num_requests = (num_requests - 1) << 16;
+		/*
+		 * Set number of requests field in packed write header to be
+		 * smaller than the actual number (1 byte, offset 2 in header)
+		 */
+		packed_cmd_hdr[0] = (packed_cmd_hdr[0] &
+				     ~PACKED_HDR_NUM_REQS_MASK) + num_requests;
+		break;
+	case TEST_HDR_REQ_NUM_LARGER_THAN_ACTUAL:
+		test_pr_info("%s: request num larger than actual" , __func__);
+		num_requests = (packed_cmd_hdr[0] & PACKED_HDR_NUM_REQS_MASK)
+									>> 16;
+		/* num of entries is incremented by 1 */
+		num_requests = (num_requests + 1) << 16;
+		/*
+		 * Set number of requests field in packed write header to be
+		 * larger than the actual number (1 byte, offset 2 in header).
+		 */
+		packed_cmd_hdr[0] = (packed_cmd_hdr[0] &
+				     ~PACKED_HDR_NUM_REQS_MASK) + num_requests;
+		break;
+	case TEST_HDR_CMD23_PACKED_BIT_SET:
+		test_pr_info("%s: header CMD23 packed bit set" , __func__);
+		/*
+		 * Set packed bit (bit 30) in cmd23 argument of first and second
+		 * write requests in packed write header.
+		 * These are located at bytes 2 and 4 in packed write header
+		 */
+		packed_cmd_hdr[2] = packed_cmd_hdr[2] | CMD23_PACKED_BIT;
+		packed_cmd_hdr[4] = packed_cmd_hdr[4] | CMD23_PACKED_BIT;
+		break;
+	case TEST_CMD23_MAX_PACKED_WRITES:
+		test_pr_info("%s: CMD23 request num > max_packed_reqs",
+			      __func__);
+		/*
+		 * Set the individual packed cmd23 request num to
+		 * max_packed_reqs + 1
+		 */
+		brq->sbc.arg = MMC_CMD23_ARG_PACKED | (max_packed_reqs + 1);
+		break;
+	case TEST_CMD23_ZERO_PACKED_WRITES:
+		test_pr_info("%s: CMD23 request num = 0", __func__);
+		/* Set the individual packed cmd23 request num to zero */
+		brq->sbc.arg = MMC_CMD23_ARG_PACKED;
+		break;
+	case TEST_CMD23_PACKED_BIT_UNSET:
+		test_pr_info("%s: CMD23 packed bit unset", __func__);
+		/*
+		 * Set the individual packed cmd23 packed bit to 0,
+		 *  although there is a packed write request
+		 */
+		brq->sbc.arg &= ~CMD23_PACKED_BIT;
+		break;
+	case TEST_CMD23_REL_WR_BIT_SET:
+		test_pr_info("%s: CMD23 REL WR bit set", __func__);
+		/* Set the individual packed cmd23 reliable write bit */
+		brq->sbc.arg = MMC_CMD23_ARG_PACKED | MMC_CMD23_ARG_REL_WR;
+		break;
+	case TEST_CMD23_BITS_16TO29_SET:
+		test_pr_info("%s: CMD23 bits [16-29] set", __func__);
+		brq->sbc.arg = MMC_CMD23_ARG_PACKED |
+			PACKED_HDR_BITS_16_TO_29_SET;
+		break;
+	case TEST_CMD23_HDR_BLK_NOT_IN_COUNT:
+		test_pr_info("%s: CMD23 hdr not in block count", __func__);
+		brq->sbc.arg = MMC_CMD23_ARG_PACKED |
+		((rq_data_dir(req) == READ) ? 0 : mqrq->packed_blocks);
+		break;
+	default:
+		test_pr_err("%s: unexpected testcase %d",
+			__func__, mbtd->test_info.testcase);
+		break;
+	}
+}
+
+/*
+ * A callback assigned to the err_check_fn field of the mmc_request by the
+ * MMC/card/block layer.
+ * Called upon request completion by the MMC/core layer.
+ * Here we emulate an error return value from the card.
+ */
+static int test_err_check(struct mmc_card *card, struct mmc_async_req *areq)
+{
+	struct mmc_queue_req *mq_rq = container_of(areq, struct mmc_queue_req,
+			mmc_active);
+	struct request_queue *req_q = test_iosched_get_req_queue();
+	struct mmc_queue *mq;
+	int max_packed_reqs;
+	int ret = 0;
+
+	if (req_q)
+		mq = req_q->queuedata;
+	else {
+		test_pr_err("%s: NULL request_queue", __func__);
+		return 0;
+	}
+
+	if (!mq) {
+		test_pr_err("%s: %s: NULL mq", __func__,
+			mmc_hostname(card->host));
+		return 0;
+	}
+
+	max_packed_reqs = mq->card->ext_csd.max_packed_writes;
+
+	if (!mq_rq) {
+		test_pr_err("%s: %s: NULL mq_rq", __func__,
+			mmc_hostname(card->host));
+		return 0;
+	}
+
+	switch (mbtd->test_info.testcase) {
+	case TEST_RET_ABORT:
+		test_pr_info("%s: return abort", __func__);
+		ret = MMC_BLK_ABORT;
+		break;
+	case TEST_RET_PARTIAL_FOLLOWED_BY_SUCCESS:
+		test_pr_info("%s: return partial followed by success",
+			      __func__);
+		/*
+		 * Since in this testcase num_requests is always >= 2,
+		 * we can be sure that packed_fail_idx is always >= 1
+		 */
+		mq_rq->packed_fail_idx = (mbtd->num_requests / 2);
+		test_pr_info("%s: packed_fail_idx = %d"
+			, __func__, mq_rq->packed_fail_idx);
+		mq->err_check_fn = NULL;
+		ret = MMC_BLK_PARTIAL;
+		break;
+	case TEST_RET_PARTIAL_FOLLOWED_BY_ABORT:
+		if (!mbtd->err_check_counter) {
+			test_pr_info("%s: return partial followed by abort",
+				      __func__);
+			mbtd->err_check_counter++;
+			/*
+			 * Since in this testcase num_requests is always >= 3,
+			 * we have that packed_fail_idx is always >= 1
+			 */
+			mq_rq->packed_fail_idx = (mbtd->num_requests / 2);
+			test_pr_info("%s: packed_fail_idx = %d"
+				, __func__, mq_rq->packed_fail_idx);
+			ret = MMC_BLK_PARTIAL;
+			break;
+		}
+		mbtd->err_check_counter = 0;
+		mq->err_check_fn = NULL;
+		ret = MMC_BLK_ABORT;
+		break;
+	case TEST_RET_PARTIAL_MULTIPLE_UNTIL_SUCCESS:
+		test_pr_info("%s: return partial multiple until success",
+			     __func__);
+		if (++mbtd->err_check_counter >= (mbtd->num_requests)) {
+			mq->err_check_fn = NULL;
+			mbtd->err_check_counter = 0;
+			ret = MMC_BLK_PARTIAL;
+			break;
+		}
+		mq_rq->packed_fail_idx = 1;
+		ret = MMC_BLK_PARTIAL;
+		break;
+	case TEST_RET_PARTIAL_MAX_FAIL_IDX:
+		test_pr_info("%s: return partial max fail_idx", __func__);
+		mq_rq->packed_fail_idx = max_packed_reqs - 1;
+		mq->err_check_fn = NULL;
+		ret = MMC_BLK_PARTIAL;
+		break;
+	case TEST_RET_RETRY:
+		test_pr_info("%s: return retry", __func__);
+		ret = MMC_BLK_RETRY;
+		break;
+	case TEST_RET_CMD_ERR:
+		test_pr_info("%s: return cmd err", __func__);
+		ret = MMC_BLK_CMD_ERR;
+		break;
+	case TEST_RET_DATA_ERR:
+		test_pr_info("%s: return data err", __func__);
+		ret = MMC_BLK_DATA_ERR;
+		break;
+	default:
+		test_pr_err("%s: unexpected testcase %d",
+			__func__, mbtd->test_info.testcase);
+	}
+
+	return ret;
+}
+
+/*
+ * This is a specific implementation for the get_test_case_str_fn function
+ * pointer in the test_info data structure. Given a valid test_data instance,
+ * the function returns a string resembling the test name, based on the testcase
+ */
+static char *get_test_case_str(struct test_data *td)
+{
+	if (!td) {
+		test_pr_err("%s: NULL td", __func__);
+		return NULL;
+	}
+
+	switch (td->test_info.testcase) {
+	case TEST_STOP_DUE_TO_FLUSH:
+		return "Test stop due to flush";
+	case TEST_STOP_DUE_TO_FLUSH_AFTER_MAX_REQS:
+		return "Test stop due to flush after max-1 reqs";
+	case TEST_STOP_DUE_TO_READ:
+		return "Test stop due to read";
+	case TEST_STOP_DUE_TO_READ_AFTER_MAX_REQS:
+		return "Test stop due to read after max-1 reqs";
+	case TEST_STOP_DUE_TO_EMPTY_QUEUE:
+		return "Test stop due to empty queue";
+	case TEST_STOP_DUE_TO_MAX_REQ_NUM:
+		return "Test stop due to max req num";
+	case TEST_STOP_DUE_TO_THRESHOLD:
+		return "Test stop due to exceeding threshold";
+	case TEST_RET_ABORT:
+		return "Test err_check return abort";
+	case TEST_RET_PARTIAL_FOLLOWED_BY_SUCCESS:
+		return "Test err_check return partial followed by success";
+	case TEST_RET_PARTIAL_FOLLOWED_BY_ABORT:
+		return "Test err_check return partial followed by abort";
+	case TEST_RET_PARTIAL_MULTIPLE_UNTIL_SUCCESS:
+		return "Test err_check return partial multiple until success";
+	case TEST_RET_PARTIAL_MAX_FAIL_IDX:
+		return "Test err_check return partial max fail index";
+	case TEST_RET_RETRY:
+		return "Test err_check return retry";
+	case TEST_RET_CMD_ERR:
+		return "Test err_check return cmd error";
+	case TEST_RET_DATA_ERR:
+		return "Test err_check return data error";
+	case TEST_HDR_INVALID_VERSION:
+		return "Test invalid - wrong header version";
+	case TEST_HDR_WRONG_WRITE_CODE:
+		return "Test invalid - wrong write code";
+	case TEST_HDR_INVALID_RW_CODE:
+		return "Test invalid - wrong R/W code";
+	case TEST_HDR_DIFFERENT_ADDRESSES:
+		return "Test invalid - header different addresses";
+	case TEST_HDR_REQ_NUM_SMALLER_THAN_ACTUAL:
+		return "Test invalid - header req num smaller than actual";
+	case TEST_HDR_REQ_NUM_LARGER_THAN_ACTUAL:
+		return "Test invalid - header req num larger than actual";
+	case TEST_HDR_CMD23_PACKED_BIT_SET:
+		return "Test invalid - header cmd23 packed bit set";
+	case TEST_CMD23_MAX_PACKED_WRITES:
+		return "Test invalid - cmd23 max packed writes";
+	case TEST_CMD23_ZERO_PACKED_WRITES:
+		return "Test invalid - cmd23 zero packed writes";
+	case TEST_CMD23_PACKED_BIT_UNSET:
+		return "Test invalid - cmd23 packed bit unset";
+	case TEST_CMD23_REL_WR_BIT_SET:
+		return "Test invalid - cmd23 rel wr bit set";
+	case TEST_CMD23_BITS_16TO29_SET:
+		return "Test invalid - cmd23 bits [16-29] set";
+	case TEST_CMD23_HDR_BLK_NOT_IN_COUNT:
+		return "Test invalid - cmd23 header block not in count";
+	default:
+		 return "Unknown testcase";
+	}
+
+	return NULL;
+}
+
+/*
+ * Compare individual testcase's statistics to the expected statistics:
+ * Compare stop reason and number of packing events
+ */
+static int check_wr_packing_statistics(struct test_data *td)
+{
+	struct mmc_wr_pack_stats *mmc_packed_stats;
+	struct mmc_queue *mq = td->req_q->queuedata;
+	int max_packed_reqs = mq->card->ext_csd.max_packed_writes;
+	int i;
+	struct mmc_card *card = mq->card;
+	struct mmc_wr_pack_stats expected_stats;
+	int *stop_reason;
+	int ret = 0;
+
+	if (!mq) {
+		test_pr_err("%s: NULL mq", __func__);
+		return -EINVAL;
+	}
+
+	expected_stats = mbtd->exp_packed_stats;
+
+	mmc_packed_stats = mmc_blk_get_packed_statistics(card);
+	if (!mmc_packed_stats) {
+		test_pr_err("%s: NULL mmc_packed_stats", __func__);
+		return -EINVAL;
+	}
+
+	if (!mmc_packed_stats->packing_events) {
+		test_pr_err("%s: NULL packing_events", __func__);
+		return -EINVAL;
+	}
+
+	spin_lock(&mmc_packed_stats->lock);
+
+	if (!mmc_packed_stats->enabled) {
+		test_pr_err("%s write packing statistics are not enabled",
+			     __func__);
+		ret = -EINVAL;
+		goto exit_err;
+	}
+
+	stop_reason = mmc_packed_stats->pack_stop_reason;
+
+	for (i = 1; i <= max_packed_reqs; ++i) {
+		if (mmc_packed_stats->packing_events[i] !=
+		    expected_stats.packing_events[i]) {
+			test_pr_err(
+			"%s: Wrong pack stats in index %d, got %d, expected %d",
+			__func__, i, mmc_packed_stats->packing_events[i],
+			       expected_stats.packing_events[i]);
+			if (td->fs_wr_reqs_during_test)
+				goto cancel_round;
+			ret = -EINVAL;
+			goto exit_err;
+		}
+	}
+
+	if (mmc_packed_stats->pack_stop_reason[EXCEEDS_SEGMENTS] !=
+	    expected_stats.pack_stop_reason[EXCEEDS_SEGMENTS]) {
+		test_pr_err(
+		"%s: Wrong pack stop reason EXCEEDS_SEGMENTS %d, expected %d",
+			__func__, stop_reason[EXCEEDS_SEGMENTS],
+		       expected_stats.pack_stop_reason[EXCEEDS_SEGMENTS]);
+		if (td->fs_wr_reqs_during_test)
+			goto cancel_round;
+		ret = -EINVAL;
+		goto exit_err;
+	}
+
+	if (mmc_packed_stats->pack_stop_reason[EXCEEDS_SECTORS] !=
+	    expected_stats.pack_stop_reason[EXCEEDS_SECTORS]) {
+		test_pr_err(
+		"%s: Wrong pack stop reason EXCEEDS_SECTORS %d, expected %d",
+			__func__, stop_reason[EXCEEDS_SECTORS],
+		       expected_stats.pack_stop_reason[EXCEEDS_SECTORS]);
+		if (td->fs_wr_reqs_during_test)
+			goto cancel_round;
+		ret = -EINVAL;
+		goto exit_err;
+	}
+
+	if (mmc_packed_stats->pack_stop_reason[WRONG_DATA_DIR] !=
+	    expected_stats.pack_stop_reason[WRONG_DATA_DIR]) {
+		test_pr_err(
+		"%s: Wrong pack stop reason WRONG_DATA_DIR %d, expected %d",
+		       __func__, stop_reason[WRONG_DATA_DIR],
+		       expected_stats.pack_stop_reason[WRONG_DATA_DIR]);
+		if (td->fs_wr_reqs_during_test)
+			goto cancel_round;
+		ret = -EINVAL;
+		goto exit_err;
+	}
+
+	if (mmc_packed_stats->pack_stop_reason[FLUSH_OR_DISCARD] !=
+	    expected_stats.pack_stop_reason[FLUSH_OR_DISCARD]) {
+		test_pr_err(
+		"%s: Wrong pack stop reason FLUSH_OR_DISCARD %d, expected %d",
+		       __func__, stop_reason[FLUSH_OR_DISCARD],
+		       expected_stats.pack_stop_reason[FLUSH_OR_DISCARD]);
+		if (td->fs_wr_reqs_during_test)
+			goto cancel_round;
+		ret = -EINVAL;
+		goto exit_err;
+	}
+
+	if (mmc_packed_stats->pack_stop_reason[EMPTY_QUEUE] !=
+	    expected_stats.pack_stop_reason[EMPTY_QUEUE]) {
+		test_pr_err(
+		"%s: Wrong pack stop reason EMPTY_QUEUE %d, expected %d",
+		       __func__, stop_reason[EMPTY_QUEUE],
+		       expected_stats.pack_stop_reason[EMPTY_QUEUE]);
+		if (td->fs_wr_reqs_during_test)
+			goto cancel_round;
+		ret = -EINVAL;
+		goto exit_err;
+	}
+
+	if (mmc_packed_stats->pack_stop_reason[REL_WRITE] !=
+	    expected_stats.pack_stop_reason[REL_WRITE]) {
+		test_pr_err(
+			"%s: Wrong pack stop reason REL_WRITE %d, expected %d",
+		       __func__, stop_reason[REL_WRITE],
+		       expected_stats.pack_stop_reason[REL_WRITE]);
+		if (td->fs_wr_reqs_during_test)
+			goto cancel_round;
+		ret = -EINVAL;
+		goto exit_err;
+	}
+
+exit_err:
+	spin_unlock(&mmc_packed_stats->lock);
+	if (ret && mmc_packed_stats->enabled)
+		print_mmc_packing_stats(card);
+	return ret;
+cancel_round:
+	spin_unlock(&mmc_packed_stats->lock);
+	test_iosched_set_ignore_round(true);
+	return 0;
+}
+
+/*
+ * Pseudo-randomly choose a seed based on the last seed, and update it in
+ * seed_number. then return seed_number (mod max_val), or min_val.
+ */
+static unsigned int pseudo_random_seed(unsigned int *seed_number,
+				       unsigned int min_val,
+				       unsigned int max_val)
+{
+	int ret = 0;
+
+	if (!seed_number)
+		return 0;
+
+	*seed_number = ((unsigned int)(((unsigned long)*seed_number *
+				(unsigned long)LARGE_PRIME_1) + LARGE_PRIME_2));
+	ret = (unsigned int)((*seed_number) % max_val);
+
+	return (ret > min_val ? ret : min_val);
+}
+
+/*
+ * Given a pseudo-random seed, find a pseudo-random num_of_bios.
+ * Make sure that num_of_bios is not larger than TEST_MAX_SECTOR_RANGE
+ */
+static void pseudo_rnd_num_of_bios(unsigned int *num_bios_seed,
+				   unsigned int *num_of_bios)
+{
+	do {
+		*num_of_bios = pseudo_random_seed(num_bios_seed, 1,
+						  TEST_MAX_BIOS_PER_REQ);
+		if (!(*num_of_bios))
+			*num_of_bios = 1;
+	} while ((*num_of_bios) * BIO_U32_SIZE * 4 > TEST_MAX_SECTOR_RANGE);
+}
+
+/* Add a single read request to the given td's request queue */
+static int prepare_request_add_read(struct test_data *td)
+{
+	int ret;
+	int start_sec;
+
+	if (td)
+		start_sec = td->start_sector;
+	else {
+		test_pr_err("%s: NULL td", __func__);
+		return 0;
+	}
+
+	test_pr_info("%s: Adding a read request, first req_id=%d", __func__,
+		     td->wr_rd_next_req_id);
+
+	ret = test_iosched_add_wr_rd_test_req(0, READ, start_sec, 2,
+					      TEST_PATTERN_5A, NULL);
+	if (ret) {
+		test_pr_err("%s: failed to add a read request", __func__);
+		return ret;
+	}
+
+	return 0;
+}
+
+/* Add a single flush request to the given td's request queue */
+static int prepare_request_add_flush(struct test_data *td)
+{
+	int ret;
+
+	if (!td) {
+		test_pr_err("%s: NULL td", __func__);
+		return 0;
+	}
+
+	test_pr_info("%s: Adding a flush request, first req_id=%d", __func__,
+		     td->unique_next_req_id);
+	ret = test_iosched_add_unique_test_req(0, REQ_UNIQUE_FLUSH,
+				  0, 0, NULL);
+	if (ret) {
+		test_pr_err("%s: failed to add a flush request", __func__);
+		return ret;
+	}
+
+	return ret;
+}
+
+/*
+ * Add num_requets amount of write requests to the given td's request queue.
+ * If random test mode is chosen we pseudo-randomly choose the number of bios
+ * for each write request, otherwise add between 1 to 5 bio per request.
+ */
+static int prepare_request_add_write_reqs(struct test_data *td,
+					  int num_requests, int is_err_expected,
+					  int is_random)
+{
+	int i;
+	unsigned int start_sec;
+	int num_bios;
+	int ret = 0;
+	unsigned int *bio_seed = &mbtd->random_test_seed;
+
+	if (td)
+		start_sec = td->start_sector;
+	else {
+		test_pr_err("%s: NULL td", __func__);
+		return ret;
+	}
+
+	test_pr_info("%s: Adding %d write requests, first req_id=%d", __func__,
+		     num_requests, td->wr_rd_next_req_id);
+
+	for (i = 1; i <= num_requests; i++) {
+		start_sec = td->start_sector + 4096 * td->num_of_write_bios;
+		if (is_random)
+			pseudo_rnd_num_of_bios(bio_seed, &num_bios);
+		else
+			/*
+			 * For the non-random case, give num_bios a value
+			 * between 1 and 5, to keep a small number of BIOs
+			 */
+			num_bios = (i%5)+1;
+
+		ret = test_iosched_add_wr_rd_test_req(is_err_expected, WRITE,
+				start_sec, num_bios, TEST_PATTERN_5A, NULL);
+
+		if (ret) {
+			test_pr_err("%s: failed to add a write request",
+				    __func__);
+			return ret;
+		}
+	}
+	return 0;
+}
+
+/*
+ * Prepare the write, read and flush requests for a generic packed commands
+ * testcase
+ */
+static int prepare_packed_requests(struct test_data *td, int is_err_expected,
+				   int num_requests, int is_random)
+{
+	int ret = 0;
+	struct mmc_queue *mq;
+	int max_packed_reqs;
+	struct request_queue *req_q;
+
+	if (!td) {
+		pr_err("%s: NULL td", __func__);
+		return -EINVAL;
+	}
+
+	req_q = td->req_q;
+
+	if (!req_q) {
+		pr_err("%s: NULL request queue", __func__);
+		return -EINVAL;
+	}
+
+	mq = req_q->queuedata;
+	if (!mq) {
+		test_pr_err("%s: NULL mq", __func__);
+		return -EINVAL;
+	}
+
+	max_packed_reqs = mq->card->ext_csd.max_packed_writes;
+
+	if (mbtd->random_test_seed <= 0) {
+		mbtd->random_test_seed =
+			(unsigned int)(get_jiffies_64() & 0xFFFF);
+		test_pr_info("%s: got seed from jiffies %d",
+			     __func__, mbtd->random_test_seed);
+	}
+
+	mmc_blk_init_packed_statistics(mq->card);
+
+	ret = prepare_request_add_write_reqs(td, num_requests, is_err_expected,
+					     is_random);
+	if (ret)
+		return ret;
+
+	/* Avoid memory corruption in upcoming stats set */
+	if (td->test_info.testcase == TEST_STOP_DUE_TO_THRESHOLD)
+		num_requests--;
+
+	memset((void *)mbtd->exp_packed_stats.pack_stop_reason, 0,
+		sizeof(mbtd->exp_packed_stats.pack_stop_reason));
+	memset(mbtd->exp_packed_stats.packing_events, 0,
+		(max_packed_reqs + 1) * sizeof(u32));
+	if (num_requests <= max_packed_reqs)
+		mbtd->exp_packed_stats.packing_events[num_requests] = 1;
+
+	switch (td->test_info.testcase) {
+	case TEST_STOP_DUE_TO_FLUSH:
+	case TEST_STOP_DUE_TO_FLUSH_AFTER_MAX_REQS:
+		ret = prepare_request_add_flush(td);
+		if (ret)
+			return ret;
+
+		mbtd->exp_packed_stats.pack_stop_reason[FLUSH_OR_DISCARD] = 1;
+		break;
+	case TEST_STOP_DUE_TO_READ:
+	case TEST_STOP_DUE_TO_READ_AFTER_MAX_REQS:
+		ret = prepare_request_add_read(td);
+		if (ret)
+			return ret;
+
+		mbtd->exp_packed_stats.pack_stop_reason[WRONG_DATA_DIR] = 1;
+		break;
+	case TEST_STOP_DUE_TO_THRESHOLD:
+		mbtd->exp_packed_stats.packing_events[num_requests] = 1;
+		mbtd->exp_packed_stats.packing_events[1] = 1;
+		mbtd->exp_packed_stats.pack_stop_reason[THRESHOLD] = 1;
+		mbtd->exp_packed_stats.pack_stop_reason[EMPTY_QUEUE] = 1;
+		break;
+	case TEST_STOP_DUE_TO_MAX_REQ_NUM:
+	case TEST_RET_PARTIAL_MAX_FAIL_IDX:
+		mbtd->exp_packed_stats.pack_stop_reason[THRESHOLD] = 1;
+		break;
+	default:
+		mbtd->exp_packed_stats.pack_stop_reason[EMPTY_QUEUE] = 1;
+	}
+	mbtd->num_requests = num_requests;
+
+	return 0;
+}
+
+/*
+ * Prepare requests for the TEST_RET_PARTIAL_FOLLOWED_BY_ABORT testcase.
+ * In this testcase we have mixed error expectations from different
+ * write requests, hence the special prepare function.
+ */
+static int prepare_partial_followed_by_abort(struct test_data *td,
+					      int num_requests)
+{
+	int i, start_address;
+	int is_err_expected = 0;
+	int ret = 0;
+	struct mmc_queue *mq = test_iosched_get_req_queue()->queuedata;
+	int max_packed_reqs;
+
+	if (!mq) {
+		test_pr_err("%s: NULL mq", __func__);
+		return -EINVAL;
+	}
+
+	max_packed_reqs = mq->card->ext_csd.max_packed_writes;
+
+	mmc_blk_init_packed_statistics(mq->card);
+
+	for (i = 1; i <= num_requests; i++) {
+		if (i > (num_requests / 2))
+			is_err_expected = 1;
+
+		start_address = td->start_sector + 4096*td->num_of_write_bios;
+		ret = test_iosched_add_wr_rd_test_req(is_err_expected, WRITE,
+				start_address, (i%5)+1, TEST_PATTERN_5A, NULL);
+		if (ret) {
+			test_pr_err("%s: failed to add a write request",
+				    __func__);
+			return ret;
+		}
+	}
+
+	memset((void *)&mbtd->exp_packed_stats.pack_stop_reason, 0,
+		sizeof(mbtd->exp_packed_stats.pack_stop_reason));
+	memset(mbtd->exp_packed_stats.packing_events, 0,
+		(max_packed_reqs + 1) * sizeof(u32));
+	mbtd->exp_packed_stats.packing_events[num_requests] = 1;
+	mbtd->exp_packed_stats.pack_stop_reason[EMPTY_QUEUE] = 1;
+
+	mbtd->num_requests = num_requests;
+
+	return ret;
+}
+
+/*
+ * Get number of write requests for current testcase. If random test mode was
+ * chosen, pseudo-randomly choose the number of requests, otherwise set to
+ * two less than the packing threshold.
+ */
+static int get_num_requests(struct test_data *td)
+{
+	int *seed = &mbtd->random_test_seed;
+	struct request_queue *req_q;
+	struct mmc_queue *mq;
+	int max_num_requests;
+	int num_requests;
+	int min_num_requests = 2;
+	int is_random = mbtd->is_random;
+
+	req_q = test_iosched_get_req_queue();
+	if (req_q)
+		mq = req_q->queuedata;
+	else {
+		test_pr_err("%s: NULL request queue", __func__);
+		return 0;
+	}
+
+	if (!mq) {
+		test_pr_err("%s: NULL mq", __func__);
+		return -EINVAL;
+	}
+
+	max_num_requests = mq->card->ext_csd.max_packed_writes;
+	num_requests = max_num_requests - 2;
+
+	if (is_random) {
+		if (td->test_info.testcase ==
+		    TEST_RET_PARTIAL_FOLLOWED_BY_ABORT)
+			min_num_requests = 3;
+
+		num_requests = pseudo_random_seed(seed, min_num_requests,
+						  max_num_requests - 1);
+	}
+
+	return num_requests;
+}
+
+/*
+ * An implementation for the prepare_test_fn pointer in the test_info
+ * data structure. According to the testcase we add the right number of requests
+ * and decide if an error is expected or not.
+ */
+static int prepare_test(struct test_data *td)
+{
+	struct mmc_queue *mq = test_iosched_get_req_queue()->queuedata;
+	int max_num_requests;
+	int num_requests = 0;
+	int ret = 0;
+	int is_random = mbtd->is_random;
+
+	if (!mq) {
+		test_pr_err("%s: NULL mq", __func__);
+		return -EINVAL;
+	}
+
+	max_num_requests = mq->card->ext_csd.max_packed_writes;
+
+	if (is_random && mbtd->random_test_seed == 0) {
+		mbtd->random_test_seed =
+			(unsigned int)(get_jiffies_64() & 0xFFFF);
+		test_pr_info("%s: got seed from jiffies %d",
+			__func__, mbtd->random_test_seed);
+	}
+
+	num_requests = get_num_requests(td);
+
+	if (mbtd->test_group == TEST_SEND_INVALID_GROUP)
+		mq->packed_test_fn =
+				test_invalid_packed_cmd;
+
+	if (mbtd->test_group == TEST_ERR_CHECK_GROUP)
+		mq->err_check_fn = test_err_check;
+
+	switch (td->test_info.testcase) {
+	case TEST_STOP_DUE_TO_FLUSH:
+	case TEST_STOP_DUE_TO_READ:
+	case TEST_RET_PARTIAL_FOLLOWED_BY_SUCCESS:
+	case TEST_RET_PARTIAL_MULTIPLE_UNTIL_SUCCESS:
+	case TEST_STOP_DUE_TO_EMPTY_QUEUE:
+	case TEST_CMD23_PACKED_BIT_UNSET:
+		ret = prepare_packed_requests(td, 0, num_requests, is_random);
+		break;
+	case TEST_STOP_DUE_TO_FLUSH_AFTER_MAX_REQS:
+	case TEST_STOP_DUE_TO_READ_AFTER_MAX_REQS:
+		ret = prepare_packed_requests(td, 0, max_num_requests - 1,
+					      is_random);
+		break;
+	case TEST_RET_PARTIAL_FOLLOWED_BY_ABORT:
+		ret = prepare_partial_followed_by_abort(td, num_requests);
+		break;
+	case TEST_STOP_DUE_TO_MAX_REQ_NUM:
+	case TEST_RET_PARTIAL_MAX_FAIL_IDX:
+		ret = prepare_packed_requests(td, 0, max_num_requests,
+					      is_random);
+		break;
+	case TEST_STOP_DUE_TO_THRESHOLD:
+		ret = prepare_packed_requests(td, 0, max_num_requests + 1,
+					      is_random);
+		break;
+	case TEST_RET_ABORT:
+	case TEST_RET_RETRY:
+	case TEST_RET_CMD_ERR:
+	case TEST_RET_DATA_ERR:
+	case TEST_HDR_INVALID_VERSION:
+	case TEST_HDR_WRONG_WRITE_CODE:
+	case TEST_HDR_INVALID_RW_CODE:
+	case TEST_HDR_DIFFERENT_ADDRESSES:
+	case TEST_HDR_REQ_NUM_SMALLER_THAN_ACTUAL:
+	case TEST_HDR_REQ_NUM_LARGER_THAN_ACTUAL:
+	case TEST_CMD23_MAX_PACKED_WRITES:
+	case TEST_CMD23_ZERO_PACKED_WRITES:
+	case TEST_CMD23_REL_WR_BIT_SET:
+	case TEST_CMD23_BITS_16TO29_SET:
+	case TEST_CMD23_HDR_BLK_NOT_IN_COUNT:
+	case TEST_HDR_CMD23_PACKED_BIT_SET:
+		ret = prepare_packed_requests(td, 1, num_requests, is_random);
+		break;
+	default:
+		test_pr_info("%s: Invalid test case...", __func__);
+		return -EINVAL;
+	}
+
+	return ret;
+}
+
+/*
+ * An implementation for the post_test_fn in the test_info data structure.
+ * In our case we just reset the function pointers in the mmc_queue in order for
+ * the FS to be able to dispatch it's requests correctly after the test is
+ * finished.
+ */
+static int post_test(struct test_data *td)
+{
+	struct mmc_queue *mq;
+
+	if (!td)
+		return -EINVAL;
+
+	mq = td->req_q->queuedata;
+
+	if (!mq) {
+		test_pr_err("%s: NULL mq", __func__);
+		return -EINVAL;
+	}
+
+	mq->packed_test_fn = NULL;
+	mq->err_check_fn = NULL;
+
+	return 0;
+}
+
+/*
+ * This function checks, based on the current test's test_group, that the
+ * packed commands capability and control are set right. In addition, we check
+ * if the card supports the packed command feature.
+ */
+static int validate_packed_commands_settings(void)
+{
+	struct request_queue *req_q;
+	struct mmc_queue *mq;
+	int max_num_requests;
+	struct mmc_host *host;
+
+	req_q = test_iosched_get_req_queue();
+	if (!req_q) {
+		test_pr_err("%s: test_iosched_get_req_queue failed", __func__);
+		test_iosched_set_test_result(TEST_FAILED);
+		return -EINVAL;
+	}
+
+	mq = req_q->queuedata;
+	if (!mq) {
+		test_pr_err("%s: NULL mq", __func__);
+		return -EINVAL;
+	}
+
+	max_num_requests = mq->card->ext_csd.max_packed_writes;
+	host = mq->card->host;
+
+	if (!(host->caps2 && MMC_CAP2_PACKED_WR)) {
+		test_pr_err("%s: Packed Write capability disabled, exit test",
+			    __func__);
+		test_iosched_set_test_result(TEST_NOT_SUPPORTED);
+		return -EINVAL;
+	}
+
+	if (max_num_requests == 0) {
+		test_pr_err(
+		"%s: no write packing support, ext_csd.max_packed_writes=%d",
+		__func__, mq->card->ext_csd.max_packed_writes);
+		test_iosched_set_test_result(TEST_NOT_SUPPORTED);
+		return -EINVAL;
+	}
+
+	test_pr_info("%s: max number of packed requests supported is %d ",
+		     __func__, max_num_requests);
+
+	return 0;
+}
+
+static bool message_repeat;
+static int test_open(struct inode *inode, struct file *file)
+{
+	file->private_data = inode->i_private;
+	message_repeat = 1;
+	return 0;
+}
+
+/* send_packing TEST */
+static ssize_t send_write_packing_test_write(struct file *file,
+				const char __user *buf,
+				size_t count,
+				loff_t *ppos)
+{
+	int ret = 0;
+	int i = 0;
+	int number = -1;
+	int j = 0;
+
+	test_pr_info("%s: -- send_write_packing TEST --", __func__);
+
+	sscanf(buf, "%d", &number);
+
+	if (number <= 0)
+		number = 1;
+
+
+	mbtd->test_group = TEST_SEND_WRITE_PACKING_GROUP;
+
+	if (validate_packed_commands_settings())
+		return count;
+
+	if (mbtd->random_test_seed > 0)
+		test_pr_info("%s: Test seed: %d", __func__,
+			      mbtd->random_test_seed);
+
+	memset(&mbtd->test_info, 0, sizeof(struct test_info));
+
+	mbtd->test_info.data = mbtd;
+	mbtd->test_info.prepare_test_fn = prepare_test;
+	mbtd->test_info.check_test_result_fn = check_wr_packing_statistics;
+	mbtd->test_info.get_test_case_str_fn = get_test_case_str;
+	mbtd->test_info.post_test_fn = post_test;
+
+	for (i = 0; i < number; ++i) {
+		test_pr_info("%s: Cycle # %d / %d", __func__, i+1, number);
+		test_pr_info("%s: ====================", __func__);
+
+		for (j = SEND_WRITE_PACKING_MIN_TESTCASE;
+		      j <= SEND_WRITE_PACKING_MAX_TESTCASE; j++) {
+
+			mbtd->test_info.testcase = j;
+			mbtd->is_random = RANDOM_TEST;
+			ret = test_iosched_start_test(&mbtd->test_info);
+			if (ret)
+				break;
+			/* Allow FS requests to be dispatched */
+			msleep(1000);
+			mbtd->test_info.testcase = j;
+			mbtd->is_random = NON_RANDOM_TEST;
+			ret = test_iosched_start_test(&mbtd->test_info);
+			if (ret)
+				break;
+			/* Allow FS requests to be dispatched */
+			msleep(1000);
+		}
+	}
+
+	test_pr_info("%s: Completed all the test cases.", __func__);
+
+	return count;
+}
+
+static ssize_t send_write_packing_test_read(struct file *file,
+			       char __user *buffer,
+			       size_t count,
+			       loff_t *offset)
+{
+	memset((void *)buffer, 0, count);
+
+	snprintf(buffer, count,
+		 "\nsend_write_packing_test\n"
+		 "=========\n"
+		 "Description:\n"
+		 "This test checks the following scenarios\n"
+		 "- Pack due to FLUSH message\n"
+		 "- Pack due to FLUSH after threshold writes\n"
+		 "- Pack due to READ message\n"
+		 "- Pack due to READ after threshold writes\n"
+		 "- Pack due to empty queue\n"
+		 "- Pack due to threshold writes\n"
+		 "- Pack due to one over threshold writes\n");
+
+	if (message_repeat == 1) {
+		message_repeat = 0;
+		return strnlen(buffer, count);
+	} else {
+		return 0;
+	}
+}
+
+const struct file_operations send_write_packing_test_ops = {
+	.open = test_open,
+	.write = send_write_packing_test_write,
+	.read = send_write_packing_test_read,
+};
+
+/* err_check TEST */
+static ssize_t err_check_test_write(struct file *file,
+				const char __user *buf,
+				size_t count,
+				loff_t *ppos)
+{
+	int ret = 0;
+	int i = 0;
+	int number = -1;
+	int j = 0;
+
+	test_pr_info("%s: -- err_check TEST --", __func__);
+
+	sscanf(buf, "%d", &number);
+
+	if (number <= 0)
+		number = 1;
+
+	mbtd->test_group = TEST_ERR_CHECK_GROUP;
+
+	if (validate_packed_commands_settings())
+		return count;
+
+	if (mbtd->random_test_seed > 0)
+		test_pr_info("%s: Test seed: %d", __func__,
+			      mbtd->random_test_seed);
+
+	memset(&mbtd->test_info, 0, sizeof(struct test_info));
+
+	mbtd->test_info.data = mbtd;
+	mbtd->test_info.prepare_test_fn = prepare_test;
+	mbtd->test_info.check_test_result_fn = check_wr_packing_statistics;
+	mbtd->test_info.get_test_case_str_fn = get_test_case_str;
+	mbtd->test_info.post_test_fn = post_test;
+
+	for (i = 0; i < number; ++i) {
+		test_pr_info("%s: Cycle # %d / %d", __func__, i+1, number);
+		test_pr_info("%s: ====================", __func__);
+
+		for (j = ERR_CHECK_MIN_TESTCASE;
+					j <= ERR_CHECK_MAX_TESTCASE; j++) {
+			mbtd->test_info.testcase = j;
+			mbtd->is_random = RANDOM_TEST;
+			ret = test_iosched_start_test(&mbtd->test_info);
+			if (ret)
+				break;
+			/* Allow FS requests to be dispatched */
+			msleep(1000);
+			mbtd->test_info.testcase = j;
+			mbtd->is_random = NON_RANDOM_TEST;
+			ret = test_iosched_start_test(&mbtd->test_info);
+			if (ret)
+				break;
+			/* Allow FS requests to be dispatched */
+			msleep(1000);
+		}
+	}
+
+	test_pr_info("%s: Completed all the test cases.", __func__);
+
+	return count;
+}
+
+static ssize_t err_check_test_read(struct file *file,
+			       char __user *buffer,
+			       size_t count,
+			       loff_t *offset)
+{
+	memset((void *)buffer, 0, count);
+
+	snprintf(buffer, count,
+		 "\nerr_check_TEST\n"
+		 "=========\n"
+		 "Description:\n"
+		 "This test checks the following scenarios\n"
+		 "- Return ABORT\n"
+		 "- Return PARTIAL followed by success\n"
+		 "- Return PARTIAL followed by abort\n"
+		 "- Return PARTIAL multiple times until success\n"
+		 "- Return PARTIAL with fail index = threshold\n"
+		 "- Return RETRY\n"
+		 "- Return CMD_ERR\n"
+		 "- Return DATA_ERR\n");
+
+	if (message_repeat == 1) {
+		message_repeat = 0;
+		return strnlen(buffer, count);
+	} else {
+		return 0;
+	}
+}
+
+const struct file_operations err_check_test_ops = {
+	.open = test_open,
+	.write = err_check_test_write,
+	.read = err_check_test_read,
+};
+
+/* send_invalid_packed TEST */
+static ssize_t send_invalid_packed_test_write(struct file *file,
+				const char __user *buf,
+				size_t count,
+				loff_t *ppos)
+{
+	int ret = 0;
+	int i = 0;
+	int number = -1;
+	int j = 0;
+	int num_of_failures = 0;
+
+	test_pr_info("%s: -- send_invalid_packed TEST --", __func__);
+
+	sscanf(buf, "%d", &number);
+
+	if (number <= 0)
+		number = 1;
+
+	mbtd->test_group = TEST_SEND_INVALID_GROUP;
+
+	if (validate_packed_commands_settings())
+		return count;
+
+	if (mbtd->random_test_seed > 0)
+		test_pr_info("%s: Test seed: %d", __func__,
+			      mbtd->random_test_seed);
+
+	memset(&mbtd->test_info, 0, sizeof(struct test_info));
+
+	mbtd->test_info.data = mbtd;
+	mbtd->test_info.prepare_test_fn = prepare_test;
+	mbtd->test_info.check_test_result_fn = check_wr_packing_statistics;
+	mbtd->test_info.get_test_case_str_fn = get_test_case_str;
+	mbtd->test_info.post_test_fn = post_test;
+
+	for (i = 0; i < number; ++i) {
+		test_pr_info("%s: Cycle # %d / %d", __func__, i+1, number);
+		test_pr_info("%s: ====================", __func__);
+
+		for (j = INVALID_CMD_MIN_TESTCASE;
+				j <= INVALID_CMD_MAX_TESTCASE; j++) {
+
+			mbtd->test_info.testcase = j;
+			mbtd->is_random = RANDOM_TEST;
+			ret = test_iosched_start_test(&mbtd->test_info);
+			if (ret)
+				num_of_failures++;
+			/* Allow FS requests to be dispatched */
+			msleep(1000);
+
+			mbtd->test_info.testcase = j;
+			mbtd->is_random = NON_RANDOM_TEST;
+			ret = test_iosched_start_test(&mbtd->test_info);
+			if (ret)
+				num_of_failures++;
+			/* Allow FS requests to be dispatched */
+			msleep(1000);
+		}
+	}
+
+	test_pr_info("%s: Completed all the test cases.", __func__);
+
+	if (num_of_failures > 0) {
+		test_iosched_set_test_result(TEST_FAILED);
+		test_pr_err(
+			"There were %d failures during the test, TEST FAILED",
+			num_of_failures);
+	}
+	return count;
+}
+
+static ssize_t send_invalid_packed_test_read(struct file *file,
+			       char __user *buffer,
+			       size_t count,
+			       loff_t *offset)
+{
+	memset((void *)buffer, 0, count);
+
+	snprintf(buffer, count,
+		 "\nsend_invalid_packed_TEST\n"
+		 "=========\n"
+		 "Description:\n"
+		 "This test checks the following scenarios\n"
+		 "- Send an invalid header version\n"
+		 "- Send the wrong write code\n"
+		 "- Send an invalid R/W code\n"
+		 "- Send wrong start address in header\n"
+		 "- Send header with block_count smaller than actual\n"
+		 "- Send header with block_count larger than actual\n"
+		 "- Send header CMD23 packed bit set\n"
+		 "- Send CMD23 with block count over threshold\n"
+		 "- Send CMD23 with block_count equals zero\n"
+		 "- Send CMD23 packed bit unset\n"
+		 "- Send CMD23 reliable write bit set\n"
+		 "- Send CMD23 bits [16-29] set\n"
+		 "- Send CMD23 header block not in block_count\n");
+
+	if (message_repeat == 1) {
+		message_repeat = 0;
+		return strnlen(buffer, count);
+	} else {
+		return 0;
+	}
+}
+
+const struct file_operations send_invalid_packed_test_ops = {
+	.open = test_open,
+	.write = send_invalid_packed_test_write,
+	.read = send_invalid_packed_test_read,
+};
+
+static void mmc_block_test_debugfs_cleanup(void)
+{
+	debugfs_remove(mbtd->debug.random_test_seed);
+	debugfs_remove(mbtd->debug.send_write_packing_test);
+	debugfs_remove(mbtd->debug.err_check_test);
+	debugfs_remove(mbtd->debug.send_invalid_packed_test);
+}
+
+static int mmc_block_test_debugfs_init(void)
+{
+	struct dentry *utils_root, *tests_root;
+
+	utils_root = test_iosched_get_debugfs_utils_root();
+	tests_root = test_iosched_get_debugfs_tests_root();
+
+	if (!utils_root || !tests_root)
+		return -EINVAL;
+
+	mbtd->debug.random_test_seed = debugfs_create_u32(
+					"random_test_seed",
+					S_IRUGO | S_IWUGO,
+					utils_root,
+					&mbtd->random_test_seed);
+
+	if (!mbtd->debug.random_test_seed)
+		goto err_nomem;
+
+	mbtd->debug.send_write_packing_test =
+		debugfs_create_file("send_write_packing_test",
+				    S_IRUGO | S_IWUGO,
+				    tests_root,
+				    NULL,
+				    &send_write_packing_test_ops);
+
+	if (!mbtd->debug.send_write_packing_test)
+		goto err_nomem;
+
+	mbtd->debug.err_check_test =
+		debugfs_create_file("err_check_test",
+				    S_IRUGO | S_IWUGO,
+				    tests_root,
+				    NULL,
+				    &err_check_test_ops);
+
+	if (!mbtd->debug.err_check_test)
+		goto err_nomem;
+
+	mbtd->debug.send_invalid_packed_test =
+		debugfs_create_file("send_invalid_packed_test",
+				    S_IRUGO | S_IWUGO,
+				    tests_root,
+				    NULL,
+				    &send_invalid_packed_test_ops);
+
+	if (!mbtd->debug.send_invalid_packed_test)
+		goto err_nomem;
+
+	return 0;
+
+err_nomem:
+	mmc_block_test_debugfs_cleanup();
+	return -ENOMEM;
+}
+
+static void mmc_block_test_probe(void)
+{
+	struct request_queue *q = test_iosched_get_req_queue();
+	struct mmc_queue *mq;
+	int max_packed_reqs;
+
+	if (!q) {
+		test_pr_err("%s: NULL request queue", __func__);
+		return;
+	}
+
+	mq = q->queuedata;
+	if (!mq) {
+		test_pr_err("%s: NULL mq", __func__);
+		return;
+	}
+
+	max_packed_reqs = mq->card->ext_csd.max_packed_writes;
+	mbtd->exp_packed_stats.packing_events =
+			kzalloc((max_packed_reqs + 1) *
+				sizeof(*mbtd->exp_packed_stats.packing_events),
+				GFP_KERNEL);
+
+	mmc_block_test_debugfs_init();
+}
+
+static void mmc_block_test_remove(void)
+{
+	mmc_block_test_debugfs_cleanup();
+}
+
+static int __init mmc_block_test_init(void)
+{
+	mbtd = kzalloc(sizeof(struct mmc_block_test_data), GFP_KERNEL);
+	if (!mbtd) {
+		test_pr_err("%s: failed to allocate mmc_block_test_data",
+			    __func__);
+		return -ENODEV;
+	}
+
+	mbtd->bdt.init_fn = mmc_block_test_probe;
+	mbtd->bdt.exit_fn = mmc_block_test_remove;
+	INIT_LIST_HEAD(&mbtd->bdt.list);
+	test_iosched_register(&mbtd->bdt);
+
+	return 0;
+}
+
+static void __exit mmc_block_test_exit(void)
+{
+	test_iosched_unregister(&mbtd->bdt);
+	kfree(mbtd);
+}
+
+module_init(mmc_block_test_init);
+module_exit(mmc_block_test_exit);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("MMC block test");
diff --git a/drivers/mmc/card/queue.h b/drivers/mmc/card/queue.h
index 5e04938..4214f69 100644
--- a/drivers/mmc/card/queue.h
+++ b/drivers/mmc/card/queue.h
@@ -12,6 +12,17 @@  struct mmc_blk_request {
 	struct mmc_data		data;
 };
 
+enum mmc_blk_status {
+	MMC_BLK_SUCCESS = 0,
+	MMC_BLK_PARTIAL,
+	MMC_BLK_CMD_ERR,
+	MMC_BLK_RETRY,
+	MMC_BLK_ABORT,
+	MMC_BLK_DATA_ERR,
+	MMC_BLK_ECC_ERR,
+	MMC_BLK_NOMEDIUM,
+};
+
 enum mmc_packed_cmd {
 	MMC_PACKED_NONE = 0,
 	MMC_PACKED_WRITE,
@@ -45,6 +56,8 @@  struct mmc_queue {
 	struct mmc_queue_req	mqrq[2];
 	struct mmc_queue_req	*mqrq_cur;
 	struct mmc_queue_req	*mqrq_prev;
+	int (*err_check_fn) (struct mmc_card *, struct mmc_async_req *);
+	void (*packed_test_fn) (struct request_queue *, struct mmc_queue_req *);
 };
 
 extern int mmc_init_queue(struct mmc_queue *, struct mmc_card *, spinlock_t *,
@@ -58,4 +71,6 @@  extern unsigned int mmc_queue_map_sg(struct mmc_queue *,
 extern void mmc_queue_bounce_pre(struct mmc_queue_req *);
 extern void mmc_queue_bounce_post(struct mmc_queue_req *);
 
+extern void print_mmc_packing_stats(struct mmc_card *card);
+
 #endif