Handling 'short' write in some cases, e.g. disk full.

.xperior/testds/motr-single_tests.yaml

@@ -749,6 +749,16 @@ Tests:
     polltime : 30
     timeout  : 1800
 
+  - id       : 73motr-io-small-disks
+    script   : 'm0 run-st 73motr-io-small-disks'
+    dir      : src/scripts
+    executor : Xperior::Executor::MotrTest
+    sandbox  : /var/motr/root/sandbox.st-73motr-io-small-disks
+    groupname: 04motr-single-node
+    polltime : 30
+    timeout  : 1800
+
+
 
 # 25 min
 dangerous: 'yes'

ioservice/io_foms.c

@@ -1957,12 +1957,11 @@ static int io_finish(struct m0_fom *fom)
 		}
 	}
 
-	M0_LOG(M0_DEBUG, "got    fom: %"PRIi64", req_count: %"PRIi64", "
-	       "count: %"PRIx64", nob: %"PRIx64"", fom_obj->fcrw_fom_start_time,
-	       fom_obj->fcrw_req_count, fom_obj->fcrw_count, nob);
 	fom_obj->fcrw_count += nob;
-	M0_ASSERT(ergo(rc == 0,
-		       fom_obj->fcrw_req_count == fom_obj->fcrw_count));
+	M0_LOG(M0_DEBUG, "got    fom: %"PRIi64", req_count: %"PRIi64", "
+			 "count: %"PRIx64", nob: %"PRIx64 ", rc:%d",
+			 fom_obj->fcrw_fom_start_time,
+			 fom_obj->fcrw_req_count, fom_obj->fcrw_count, nob, rc);
 	rc = fom_obj->fcrw_rc ?: rc;
 	if (rc != 0) {
 		M0_LOG(M0_ERROR, "rc=%d", rc);

m0t1fs/linux_kernel/st/m0t1fs_common_inc.sh

@@ -81,6 +81,8 @@ IOS5_CMD=""       #IOS5 process commandline to spawn it again on Controller even
 
 IOS4_CMD=""
 
+export IOS_DISK_SEEK_BLOCK_COUNT=1M
+
 # list of md server end points tmid in [800, 899)
 MDSEP=(
     12345:33:800   # MDS1 EP

m0t1fs/linux_kernel/st/m0t1fs_server_inc.sh

@@ -95,7 +95,7 @@ EOF
 	for (( ; DDEV_ID < $dev_end; DDEV_ID++)) ; do
 		conf_ios_device_setup $DDEV_ID $id_count id_count "$ids" ids
 
-		dd if=/dev/zero of=$DDEV_ID$ddisk bs=1M seek=1M count=1 ||
+		dd if=/dev/zero of=$DDEV_ID$ddisk bs=1M seek=$IOS_DISK_SEEK_BLOCK_COUNT count=1 ||
 			return 1
 		if [ ! -e /dev/loop$DDEV_ID ]; then
 			create_loop_device $DDEV_ID

motr/st/utils/copy.c

@@ -128,7 +128,7 @@ int main(int argc, char **argv)
 
 	client_fini(m0_instance);
 
-	return rc == 0 ? 0 : 1;
+	return -rc;
 }
 
 /*

motr/st/utils/motr_io_small_disks.sh

@@ -0,0 +1,88 @@
+#!/usr/bin/env bash
+#
+# Copyright (c) 2022 Seagate Technology LLC and/or its Affiliates
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# For any questions about this software or licensing,
+# please email opensource@seagate.com or cortx-questions@seagate.com.
+#
+
+
+TOPDIR=$(dirname "$0")/../../../
+
+. "${TOPDIR}/m0t1fs/linux_kernel/st/common.sh"
+. "${TOPDIR}/m0t1fs/linux_kernel/st/m0t1fs_common_inc.sh"
+. "${TOPDIR}/m0t1fs/linux_kernel/st/m0t1fs_client_inc.sh"
+. "${TOPDIR}/m0t1fs/linux_kernel/st/m0t1fs_server_inc.sh"
+. "${TOPDIR}/m0t1fs/linux_kernel/st/m0t1fs_sns_common_inc.sh"
+. "${TOPDIR}/motr/st/utils/sns_repair_common_inc.sh"
+
+
+export MOTR_CLIENT_ONLY=1
+
+# The ioservice will have a very small disk to trigger -ENOSPC test
+export IOS_DISK_SEEK_BLOCK_COUNT=500
+
+motr_io_small_disks()
+{
+	local rc=0
+
+	echo "Startin motr_io_small_disks testing ..."
+
+	prepare_datafiles_and_objects
+	rc=$?
+	if [[ $rc -eq 28 ]] ; then
+		# ENOSPC == 28
+		echo "We got $rc as expected"
+		rc=0
+	else
+		echo "We got $rc. This is not expected."
+		rc=1
+	fi
+
+	return $?
+}
+
+main()
+{
+	local rc=0
+
+	sandbox_init
+
+	NODE_UUID=$(uuidgen)
+	local multiple_pools=0
+	motr_service start $multiple_pools $stride $N $K $S $P || {
+		echo "Failed to start Motr Service."
+		return 1
+	}
+
+
+	if [[ $rc -eq 0 ]] && ! motr_io_small_disks ; then
+		rc=1
+		echo "Failed: Motr I/O testing on small disks.."
+	fi
+
+	motr_service stop || {
+		echo "Failed to stop Motr Service."
+		rc=1
+	}
+	if [[ $rc -eq 0 ]]; then
+		sandbox_fini
+	fi
+	return $rc
+}
+
+trap unprepare EXIT
+main
+report_and_exit motr_io_small_disks $?

motr/st/utils/sns_repair_common_inc.sh

@@ -42,7 +42,8 @@ prepare_datafiles_and_objects()
 						 -o ${file[$i]}      \
 					 "$MOTR_M0T1FS_TEST_DIR/srcfile" || {
 			rc=$?
-			echo "Writing object ${file[$i]} failed"
+			echo "Writing object ${file[$i]} failed: $rc"
+			return $rc
 		}
 	done
 	return $rc

scripts/st.d/73motr-io-small-disks

@@ -0,0 +1,4 @@
+#!/usr/bin/env bash
+set -eu
+
+exec $SUDO "$M0_SRC_DIR/motr/st/utils/motr_io_small_disks.sh"