test: add script for verifying reads/writes

Author: mikesmitty

tools/test-usb-msc-write.sh

@@ -0,0 +1,48 @@
+#!/usr/bin/env bash
+
+set -e
+
+DISK=${1#/dev/}
+
+if [ -z "$DISK" ]; then
+    echo "Usage: $0 /dev/sdX"
+    exit 1
+fi
+
+if [ ! -b "/dev/$DISK" ]; then
+    echo "Error: /dev/$DISK is not a block device."
+    exit 1
+fi
+
+# Create a temporary file to hold the random data
+TEMPFILE=$(mktemp /tmp/test-usb-msc.XXXXXX)
+
+# Delete the temporary file on exit or error
+trap 'rm -f "$TEMPFILE"' EXIT
+
+# Generate random data to fill the disk
+dd if=/dev/urandom of=$TEMPFILE bs=$(cat /sys/block/$DISK/queue/hw_sector_size) count=$(cat /sys/block/$DISK/size)
+
+CHECKSUM=$(md5sum $TEMPFILE | awk '{print $1}')
+
+# Do a full-disk erase (unmap)
+echo "unmap" >/sys/block/$DISK/device/scsi_disk/*/provisioning_mode
+blkdiscard /dev/$DISK
+
+# Write the random data to the disk
+dd if=$TEMPFILE of=/dev/$DISK bs=$(cat /sys/block/$DISK/queue/hw_sector_size)
+
+# Flush the disk cache to read back the data directly from disk
+sync
+echo 3 >/proc/sys/vm/drop_caches
+
+# Read the data back from the disk and verify it
+DISK_CHECKSUM=$(md5sum /dev/$DISK | awk '{print $1}')
+if [ "$CHECKSUM" != "$DISK_CHECKSUM" ]; then
+    echo "Error: Checksum mismatch"
+    echo "Original checksum: $CHECKSUM"
+    echo "Read checksum: $DISK_CHECKSUM"
+    exit 1
+else
+    echo "Success: Checksum matches"
+fi