1 files changed, 313 insertions, 8 deletions

diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c
index dec6b0ec4def..a773189dfa48 100644
--- a/drivers/mmc/card/block.c
+++ b/drivers/mmc/card/block.c
@@ -36,6 +36,8 @@
 #include <linux/compat.h>
 #include <linux/pm_runtime.h>
 
+#include <trace/events/mmc.h>
+
 #include <linux/mmc/ioctl.h>
 #include <linux/mmc/card.h>
 #include <linux/mmc/host.h>
@@ -166,11 +168,7 @@ static struct mmc_blk_data *mmc_blk_get(struct gendisk *disk)
 
 static inline int mmc_get_devidx(struct gendisk *disk)
 {
-	int devmaj = MAJOR(disk_devt(disk));
-	int devidx = MINOR(disk_devt(disk)) / perdev_minors;
-
-	if (!devmaj)
-		devidx = disk->first_minor / perdev_minors;
+	int devidx = disk->first_minor / perdev_minors;
 	return devidx;
 }
 
@@ -288,6 +286,250 @@ out:
 	return ret;
 }
 
+#ifdef CONFIG_MMC_SIMULATE_MAX_SPEED
+
+static int max_read_speed, max_write_speed, cache_size = 4;
+
+module_param(max_read_speed, int, S_IRUSR | S_IRGRP);
+MODULE_PARM_DESC(max_read_speed, "maximum KB/s read speed 0=off");
+module_param(max_write_speed, int, S_IRUSR | S_IRGRP);
+MODULE_PARM_DESC(max_write_speed, "maximum KB/s write speed 0=off");
+module_param(cache_size, int, S_IRUSR | S_IRGRP);
+MODULE_PARM_DESC(cache_size, "MB high speed memory or SLC cache");
+
+/*
+ * helper macros and expectations:
+ *  size    - unsigned long number of bytes
+ *  jiffies - unsigned long HZ timestamp difference
+ *  speed   - unsigned KB/s transfer rate
+ */
+#define size_and_speed_to_jiffies(size, speed) \
+		((size) * HZ / (speed) / 1024UL)
+#define jiffies_and_speed_to_size(jiffies, speed) \
+		(((speed) * (jiffies) * 1024UL) / HZ)
+#define jiffies_and_size_to_speed(jiffies, size) \
+		((size) * HZ / (jiffies) / 1024UL)
+
+/* Limits to report warning */
+/* jiffies_and_size_to_speed(10*HZ, queue_max_hw_sectors(q) * 512UL) ~ 25 */
+#define MIN_SPEED(q) 250 /* 10 times faster than a floppy disk */
+#define MAX_SPEED(q) jiffies_and_size_to_speed(1, queue_max_sectors(q) * 512UL)
+
+#define speed_valid(speed) ((speed) > 0)
+
+static const char off[] = "off\n";
+
+static int max_speed_show(int speed, char *buf)
+{
+	if (speed)
+		return scnprintf(buf, PAGE_SIZE, "%uKB/s\n", speed);
+	else
+		return scnprintf(buf, PAGE_SIZE, off);
+}
+
+static int max_speed_store(const char *buf, struct request_queue *q)
+{
+	unsigned int limit, set = 0;
+
+	if (!strncasecmp(off, buf, sizeof(off) - 2))
+		return set;
+	if (kstrtouint(buf, 0, &set) || (set > INT_MAX))
+		return -EINVAL;
+	if (set == 0)
+		return set;
+	limit = MAX_SPEED(q);
+	if (set > limit)
+		pr_warn("max speed %u ineffective above %u\n", set, limit);
+	limit = MIN_SPEED(q);
+	if (set < limit)
+		pr_warn("max speed %u painful below %u\n", set, limit);
+	return set;
+}
+
+static ssize_t max_write_speed_show(struct device *dev,
+				 struct device_attribute *attr, char *buf)
+{
+	struct mmc_blk_data *md = mmc_blk_get(dev_to_disk(dev));
+	int ret = max_speed_show(atomic_read(&md->queue.max_write_speed), buf);
+
+	mmc_blk_put(md);
+	return ret;
+}
+
+static ssize_t max_write_speed_store(struct device *dev,
+				  struct device_attribute *attr,
+				  const char *buf, size_t count)
+{
+	struct mmc_blk_data *md = mmc_blk_get(dev_to_disk(dev));
+	int set = max_speed_store(buf, md->queue.queue);
+
+	if (set < 0) {
+		mmc_blk_put(md);
+		return set;
+	}
+
+	atomic_set(&md->queue.max_write_speed, set);
+	mmc_blk_put(md);
+	return count;
+}
+
+static const DEVICE_ATTR(max_write_speed, S_IRUGO | S_IWUSR,
+	max_write_speed_show, max_write_speed_store);
+
+static ssize_t max_read_speed_show(struct device *dev,
+				 struct device_attribute *attr, char *buf)
+{
+	struct mmc_blk_data *md = mmc_blk_get(dev_to_disk(dev));
+	int ret = max_speed_show(atomic_read(&md->queue.max_read_speed), buf);
+
+	mmc_blk_put(md);
+	return ret;
+}
+
+static ssize_t max_read_speed_store(struct device *dev,
+				  struct device_attribute *attr,
+				  const char *buf, size_t count)
+{
+	struct mmc_blk_data *md = mmc_blk_get(dev_to_disk(dev));
+	int set = max_speed_store(buf, md->queue.queue);
+
+	if (set < 0) {
+		mmc_blk_put(md);
+		return set;
+	}
+
+	atomic_set(&md->queue.max_read_speed, set);
+	mmc_blk_put(md);
+	return count;
+}
+
+static const DEVICE_ATTR(max_read_speed, S_IRUGO | S_IWUSR,
+	max_read_speed_show, max_read_speed_store);
+
+static ssize_t cache_size_show(struct device *dev,
+			       struct device_attribute *attr, char *buf)
+{
+	struct mmc_blk_data *md = mmc_blk_get(dev_to_disk(dev));
+	struct mmc_queue *mq = &md->queue;
+	int cache_size = atomic_read(&mq->cache_size);
+	int ret;
+
+	if (!cache_size)
+		ret = scnprintf(buf, PAGE_SIZE, off);
+	else {
+		int speed = atomic_read(&mq->max_write_speed);
+
+		if (!speed_valid(speed))
+			ret = scnprintf(buf, PAGE_SIZE, "%uMB\n", cache_size);
+		else { /* We accept race between cache_jiffies and cache_used */
+			unsigned long size = jiffies_and_speed_to_size(
+				jiffies - mq->cache_jiffies, speed);
+			long used = atomic_long_read(&mq->cache_used);
+
+			if (size >= used)
+				size = 0;
+			else
+				size = (used - size) * 100 / cache_size
+					/ 1024UL / 1024UL;
+
+			ret = scnprintf(buf, PAGE_SIZE, "%uMB %lu%% used\n",
+				cache_size, size);
+		}
+	}
+
+	mmc_blk_put(md);
+	return ret;
+}
+
+static ssize_t cache_size_store(struct device *dev,
+				  struct device_attribute *attr,
+				  const char *buf, size_t count)
+{
+	struct mmc_blk_data *md;
+	unsigned int set = 0;
+
+	if (strncasecmp(off, buf, sizeof(off) - 2)
+	 && (kstrtouint(buf, 0, &set) || (set > INT_MAX)))
+		return -EINVAL;
+
+	md = mmc_blk_get(dev_to_disk(dev));
+	atomic_set(&md->queue.cache_size, set);
+	mmc_blk_put(md);
+	return count;
+}
+
+static const DEVICE_ATTR(cache_size, S_IRUGO | S_IWUSR,
+	cache_size_show, cache_size_store);
+
+/* correct for write-back */
+static long mmc_blk_cache_used(struct mmc_queue *mq, unsigned long waitfor)
+{
+	long used = 0;
+	int speed = atomic_read(&mq->max_write_speed);
+
+	if (speed_valid(speed)) {
+		unsigned long size = jiffies_and_speed_to_size(
+					waitfor - mq->cache_jiffies, speed);
+		used = atomic_long_read(&mq->cache_used);
+
+		if (size >= used)
+			used = 0;
+		else
+			used -= size;
+	}
+
+	atomic_long_set(&mq->cache_used, used);
+	mq->cache_jiffies = waitfor;
+
+	return used;
+}
+
+static void mmc_blk_simulate_delay(
+	struct mmc_queue *mq,
+	struct request *req,
+	unsigned long waitfor)
+{
+	int max_speed;
+
+	if (!req)
+		return;
+
+	max_speed = (rq_data_dir(req) == READ)
+		? atomic_read(&mq->max_read_speed)
+		: atomic_read(&mq->max_write_speed);
+	if (speed_valid(max_speed)) {
+		unsigned long bytes = blk_rq_bytes(req);
+
+		if (rq_data_dir(req) != READ) {
+			int cache_size = atomic_read(&mq->cache_size);
+
+			if (cache_size) {
+				unsigned long size = cache_size * 1024L * 1024L;
+				long used = mmc_blk_cache_used(mq, waitfor);
+
+				used += bytes;
+				atomic_long_set(&mq->cache_used, used);
+				bytes = 0;
+				if (used > size)
+					bytes = used - size;
+			}
+		}
+		waitfor += size_and_speed_to_jiffies(bytes, max_speed);
+		if (time_is_after_jiffies(waitfor)) {
+			long msecs = jiffies_to_msecs(waitfor - jiffies);
+
+			if (likely(msecs > 0))
+				msleep(msecs);
+		}
+	}
+}
+
+#else
+
+#define mmc_blk_simulate_delay(mq, req, waitfor)
+
+#endif
+
 static int mmc_blk_open(struct block_device *bdev, fmode_t mode)
 {
 	struct mmc_blk_data *md = mmc_blk_get(bdev->bd_disk);
@@ -427,9 +669,11 @@ static int ioctl_do_sanitize(struct mmc_card *card)
 	pr_debug("%s: %s - SANITIZE IN PROGRESS...\n",
 		mmc_hostname(card->host), __func__);
 
+	trace_mmc_blk_erase_start(EXT_CSD_SANITIZE_START, 0, 0);
 	err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
 					EXT_CSD_SANITIZE_START, 1,
 					MMC_SANITIZE_REQ_TIMEOUT);
+	trace_mmc_blk_erase_end(EXT_CSD_SANITIZE_START, 0, 0);
 
 	if (err)
 		pr_err("%s: %s - EXT_CSD_SANITIZE_START failed. err=%d\n",
@@ -852,18 +1096,22 @@ static int mmc_blk_cmd_error(struct request *req, const char *name, int error,
 			req->rq_disk->disk_name, "timed out", name, status);
 
 		/* If the status cmd initially failed, retry the r/w cmd */
-		if (!status_valid)
+		if (!status_valid) {
+			pr_err("%s: status not valid, retrying timeout\n", req->rq_disk->disk_name);
 			return ERR_RETRY;
-
+		}
 		/*
 		 * If it was a r/w cmd crc error, or illegal command
 		 * (eg, issued in wrong state) then retry - we should
 		 * have corrected the state problem above.
 		 */
-		if (status & (R1_COM_CRC_ERROR | R1_ILLEGAL_COMMAND))
+		if (status & (R1_COM_CRC_ERROR | R1_ILLEGAL_COMMAND)) {
+			pr_err("%s: command error, retrying timeout\n", req->rq_disk->disk_name);
 			return ERR_RETRY;
+		}
 
 		/* Otherwise abort the command */
+		pr_err("%s: not retrying timeout\n", req->rq_disk->disk_name);
 		return ERR_ABORT;
 
 	default:
@@ -1159,6 +1407,23 @@ static int mmc_blk_issue_flush(struct mmc_queue *mq, struct request *req)
 	if (ret)
 		ret = -EIO;
 
+#ifdef CONFIG_MMC_SIMULATE_MAX_SPEED
+	else if (atomic_read(&mq->cache_size)) {
+		long used = mmc_blk_cache_used(mq, jiffies);
+
+		if (used) {
+			int speed = atomic_read(&mq->max_write_speed);
+
+			if (speed_valid(speed)) {
+				unsigned long msecs = jiffies_to_msecs(
+					size_and_speed_to_jiffies(
+						used, speed));
+				if (msecs)
+					msleep(msecs);
+			}
+		}
+	}
+#endif
 	blk_end_request_all(req, ret);
 
 	return ret ? 0 : 1;
@@ -1844,6 +2109,9 @@ static int mmc_blk_issue_rw_rq(struct mmc_queue *mq, struct request *rqc)
 	struct mmc_async_req *areq;
 	const u8 packed_nr = 2;
 	u8 reqs = 0;
+#ifdef CONFIG_MMC_SIMULATE_MAX_SPEED
+	unsigned long waitfor = jiffies;
+#endif
 
 	if (!rqc && !mq->mqrq_prev->req)
 		return 0;
@@ -1894,6 +2162,8 @@ static int mmc_blk_issue_rw_rq(struct mmc_queue *mq, struct request *rqc)
 			 */
 			mmc_blk_reset_success(md, type);
 
+			mmc_blk_simulate_delay(mq, rqc, waitfor);
+
 			if (mmc_packed_cmd(mq_rq->cmd_type)) {
 				ret = mmc_blk_end_packed_req(mq_rq);
 				break;
@@ -2152,6 +2422,7 @@ static struct mmc_blk_data *mmc_blk_alloc_req(struct mmc_card *card,
 	md->disk->queue = md->queue.queue;
 	md->disk->driverfs_dev = parent;
 	set_disk_ro(md->disk, md->read_only || default_ro);
+	md->disk->flags = GENHD_FL_EXT_DEVT;
 	if (area_type & (MMC_BLK_DATA_AREA_RPMB | MMC_BLK_DATA_AREA_BOOT))
 		md->disk->flags |= GENHD_FL_NO_PART_SCAN;
 
@@ -2310,6 +2581,14 @@ static void mmc_blk_remove_req(struct mmc_blk_data *md)
 					card->ext_csd.boot_ro_lockable)
 				device_remove_file(disk_to_dev(md->disk),
 					&md->power_ro_lock);
+#ifdef CONFIG_MMC_SIMULATE_MAX_SPEED
+			device_remove_file(disk_to_dev(md->disk),
+						&dev_attr_max_write_speed);
+			device_remove_file(disk_to_dev(md->disk),
+						&dev_attr_max_read_speed);
+			device_remove_file(disk_to_dev(md->disk),
+						&dev_attr_cache_size);
+#endif
 
 			del_gendisk(md->disk);
 		}
@@ -2345,6 +2624,24 @@ static int mmc_add_disk(struct mmc_blk_data *md)
 	ret = device_create_file(disk_to_dev(md->disk), &md->force_ro);
 	if (ret)
 		goto force_ro_fail;
+#ifdef CONFIG_MMC_SIMULATE_MAX_SPEED
+	atomic_set(&md->queue.max_write_speed, max_write_speed);
+	ret = device_create_file(disk_to_dev(md->disk),
+			&dev_attr_max_write_speed);
+	if (ret)
+		goto max_write_speed_fail;
+	atomic_set(&md->queue.max_read_speed, max_read_speed);
+	ret = device_create_file(disk_to_dev(md->disk),
+			&dev_attr_max_read_speed);
+	if (ret)
+		goto max_read_speed_fail;
+	atomic_set(&md->queue.cache_size, cache_size);
+	atomic_long_set(&md->queue.cache_used, 0);
+	md->queue.cache_jiffies = jiffies;
+	ret = device_create_file(disk_to_dev(md->disk), &dev_attr_cache_size);
+	if (ret)
+		goto cache_size_fail;
+#endif
 
 	if ((md->area_type & MMC_BLK_DATA_AREA_BOOT) &&
 	     card->ext_csd.boot_ro_lockable) {
@@ -2369,6 +2666,14 @@ static int mmc_add_disk(struct mmc_blk_data *md)
 	return ret;
 
 power_ro_lock_fail:
+#ifdef CONFIG_MMC_SIMULATE_MAX_SPEED
+	device_remove_file(disk_to_dev(md->disk), &dev_attr_cache_size);
+cache_size_fail:
+	device_remove_file(disk_to_dev(md->disk), &dev_attr_max_read_speed);
+max_read_speed_fail:
+	device_remove_file(disk_to_dev(md->disk), &dev_attr_max_write_speed);
+max_write_speed_fail:
+#endif
 	device_remove_file(disk_to_dev(md->disk), &md->force_ro);
 force_ro_fail:
 	del_gendisk(md->disk);