mtd: tests: add count parameter to mtd_speedtest

By default mtd_speedtest uses all the eraseblocks of the
MTD partition being tested.  For large partitions a
smaller number is sufficient and makes running the test
quicker.  For that reason, add a parameter 'count' to
specify the maximum number of eraseblocks to use for
testing.
Signed-off-by: NAdrian Hunter <adrian.hunter@nokia.com>
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

drivers/mtd/tests/mtd_speedtest.c

@@ -16,7 +16,7 @@
  *
  * Test read and write speed of a MTD device.
  *
- * Author: Adrian Hunter <ext-adrian.hunter@nokia.com>
+ * Author: Adrian Hunter <adrian.hunter@nokia.com>
  */
 
 #include <linux/init.h>
@@ -33,6 +33,11 @@ static int dev;
 module_param(dev, int, S_IRUGO);
 MODULE_PARM_DESC(dev, "MTD device number to use");
 
+static int count;
+module_param(count, int, S_IRUGO);
+MODULE_PARM_DESC(count, "Maximum number of eraseblocks to use "
+			"(0 means use all)");
+
 static struct mtd_info *mtd;
 static unsigned char *iobuf;
 static unsigned char *bbt;
@@ -326,7 +331,10 @@ static int __init mtd_speedtest_init(void)
 
 	printk(KERN_INFO "\n");
 	printk(KERN_INFO "=================================================\n");
-	printk(PRINT_PREF "MTD device: %d\n", dev);
+	if (count)
+		printk(PRINT_PREF "MTD device: %d    count: %d\n", dev, count);
+	else
+		printk(PRINT_PREF "MTD device: %d\n", dev);
 
 	mtd = get_mtd_device(NULL, dev);
 	if (IS_ERR(mtd)) {
@@ -353,6 +361,9 @@ static int __init mtd_speedtest_init(void)
 	       (unsigned long long)mtd->size, mtd->erasesize,
 	       pgsize, ebcnt, pgcnt, mtd->oobsize);
 
+	if (count > 0 && count < ebcnt)
+		ebcnt = count;
+
 	err = -ENOMEM;
 	iobuf = kmalloc(mtd->erasesize, GFP_KERNEL);
 	if (!iobuf) {