[PATCH 16/18] iotests: Allow testing FUSE exports

[Max Reitz]

This pretends FUSE exports are a kind of protocol.  As such, they are
always tested under the format node.  This is probably the best way to
test them, actually, because this will generate more I/O load and more
varied patterns.

Signed-off-by: Max Reitz <address@hidden>
---
 tests/qemu-iotests/check         |   6 ++
 tests/qemu-iotests/common.filter |   5 +-
 tests/qemu-iotests/common.rc     | 148 +++++++++++++++++++++++++++++++
 3 files changed, 158 insertions(+), 1 deletion(-)

diff --git a/tests/qemu-iotests/check b/tests/qemu-iotests/check
index 90970b0549..dcb725e4eb 100755
--- a/tests/qemu-iotests/check
+++ b/tests/qemu-iotests/check
@@ -263,6 +263,7 @@ image protocol options
     -rbd                test rbd
     -sheepdog           test sheepdog
     -nbd                test nbd
+    -fuse               test fuse
     -ssh                test ssh
     -nfs                test nfs
     -vxhs               test vxhs
@@ -375,6 +376,11 @@ testlist options
             xpand=false
             ;;
 
+        -fuse)
+            IMGPROTO=fuse
+            xpand=false
+            ;;
+
         -vxhs)
             IMGPROTO=vxhs
             xpand=false
diff --git a/tests/qemu-iotests/common.filter b/tests/qemu-iotests/common.filter
index 3f8ee3e5f7..5f48351cae 100644
--- a/tests/qemu-iotests/common.filter
+++ b/tests/qemu-iotests/common.filter
@@ -44,7 +44,8 @@ _filter_qom_path()
 _filter_testdir()
 {
     $SED -e "s#$TEST_DIR/#TEST_DIR/#g" \
-         -e "s#$SOCK_DIR/#SOCK_DIR/#g"
+         -e "s#$SOCK_DIR/#SOCK_DIR/#g" \
+         -e "s#SOCK_DIR/fuse-#TEST_DIR/#g"
 }
 
 # replace occurrences of the actual IMGFMT value with IMGFMT
@@ -135,6 +136,7 @@ _filter_img_create()
         -e "s#$IMGFMT#IMGFMT#g" \
         -e 's#nbd:127.0.0.1:[0-9]\\+#TEST_DIR/t.IMGFMT#g' \
         -e 's#nbd+unix:///\??socket=SOCK_DIR/nbd#TEST_DIR/t.IMGFMT#g' \
+        -e 's#SOCK_DIR/fuse-#TEST_DIR/#g' \
         -e "s# encryption=off##g" \
         -e "s# cluster_size=[0-9]\\+##g" \
         -e "s# table_size=[0-9]\\+##g" \
@@ -173,6 +175,7 @@ _filter_img_info()
         -e "s#$IMGFMT#IMGFMT#g" \
         -e 's#nbd://127.0.0.1:[0-9]\\+$#TEST_DIR/t.IMGFMT#g' \
         -e 's#nbd+unix:///\??socket=SOCK_DIR/nbd#TEST_DIR/t.IMGFMT#g' \
+        -e 's#SOCK_DIR/fuse-#TEST_DIR/#g' \
         -e 's#json.*vdisk-id.*vxhs"}}#TEST_DIR/t.IMGFMT#' \
         -e "/encrypted: yes/d" \
         -e "/cluster_size: [0-9]\\+/d" \
diff --git a/tests/qemu-iotests/common.rc b/tests/qemu-iotests/common.rc
index 192c988401..fbd8fb7309 100644
--- a/tests/qemu-iotests/common.rc
+++ b/tests/qemu-iotests/common.rc
@@ -219,6 +219,9 @@ if [ "$IMGOPTSSYNTAX" = "true" ]; then
         TEST_IMG_FILE=$TEST_DIR/t.$IMGFMT
         TEST_IMG="$DRIVER,file.driver=nbd,file.type=unix"
         TEST_IMG="$TEST_IMG,file.path=$SOCK_DIR/nbd"
+    elif [ "$IMGPROTO" = "fuse" ]; then
+        TEST_IMG_FILE=$TEST_DIR/t.$IMGFMT
+        TEST_IMG="$DRIVER,file.filename=$SOCK_DIR/fuse-t.$IMGFMT"
     elif [ "$IMGPROTO" = "ssh" ]; then
         TEST_IMG_FILE=$TEST_DIR/t.$IMGFMT
         
TEST_IMG="$DRIVER,file.driver=ssh,file.host=127.0.0.1,file.path=$TEST_IMG_FILE"
@@ -235,6 +238,9 @@ else
     elif [ "$IMGPROTO" = "nbd" ]; then
         TEST_IMG_FILE=$TEST_DIR/t.$IMGFMT
         TEST_IMG="nbd+unix:///?socket=$SOCK_DIR/nbd"
+    elif [ "$IMGPROTO" = "fuse" ]; then
+        TEST_IMG_FILE=$TEST_DIR/t.$IMGFMT
+        TEST_IMG="$SOCK_DIR/fuse-t.$IMGFMT"
     elif [ "$IMGPROTO" = "ssh" ]; then
         TEST_IMG_FILE=$TEST_DIR/t.$IMGFMT
         
REMOTE_TEST_DIR="ssh://\\($USER@\\)\\?127.0.0.1\\(:[0-9]\\+\\)\\?$TEST_DIR"
@@ -253,6 +259,9 @@ fi
 ORIG_TEST_IMG_FILE=$TEST_IMG_FILE
 ORIG_TEST_IMG="$TEST_IMG"
 
+FUSE_PIDS=()
+FUSE_EXPORTS=()
+
 if [ -z "$TEST_DIR" ]; then
         TEST_DIR=$PWD/scratch
 fi
@@ -322,6 +331,10 @@ _test_img_to_test_img_file()
             echo "$1"
             ;;
 
+        fuse)
+            echo "$1" | sed -e "s#$SOCK_DIR/fuse-#$TEST_DIR/#"
+            ;;
+
         nfs)
             echo "$1" | sed -e "s#nfs://127.0.0.1##"
             ;;
@@ -353,6 +366,11 @@ _make_test_img()
     local opts_param=false
     local misc_params=()
 
+    if [[ $IMGPROTO == fuse && $TEST_IMG == $SOCK_DIR/fuse-* ]]; then
+        # The caller may be trying to overwrite an existing image
+        _rm_test_img "$TEST_IMG"
+    fi
+
     if [ -z "$TEST_IMG_FILE" ]; then
         img_name=$TEST_IMG
     elif [ "$TEST_IMG_FILE" = "$ORIG_TEST_IMG_FILE" ]; then
@@ -437,6 +455,68 @@ _make_test_img()
         sleep 1 # FIXME: qemu-nbd needs to be listening before we continue
     fi
 
+    if [ $IMGPROTO = "fuse" -a -f "$img_name" ]; then
+        local export_mp
+        local pid
+        local pidfile
+        local timeout
+
+        export_mp=$(echo "$img_name" | sed -e "s#$TEST_DIR/#$SOCK_DIR/fuse-#")
+        if ! echo "$export_mp" | grep -q "^$SOCK_DIR"; then
+            echo 'Cannot use FUSE exports with images outside of TEST_DIR' >&2
+            return 1
+        fi
+
+        touch "$export_mp"
+        rm -f "$SOCK_DIR/fuse-output"
+
+        # Usually, users would export formatted nodes.  But we present fuse as 
a
+        # protocol-level driver here, so we have to leave the format to the
+        # client.
+        echo "{'execute': 'qmp_capabilities'}
+              {'execute': 'fuse-export-add',
+               'arguments': { 'node-name': 'export-node',
+                              'mountpoint': '$export_mp',
+                              'writable': true,
+                              'growable': true }}" | \
+        QEMU_NEED_PID=y _QEMU_HANDLE=fuse $QEMU -qmp stdio \
+              -M none,accel=qtest -qtest null \
+              -blockdev 
file,node-name=export-node,filename=$img_name,discard=unmap \
+              >$SOCK_DIR/fuse-output &
+
+        pidfile="$QEMU_TEST_DIR/qemu-fuse.pid"
+
+        # Wait for the PID file
+        while [ ! -f "$pidfile" ]; do
+            sleep 0.5
+        done
+
+        pid=$(cat "$pidfile")
+        rm -f "$pidfile"
+
+        # Wait until the node is exported (i.e., both QMP commands
+        # have been completed)
+        timeout=10 # *0.5 s
+        while [ "$(grep -c return "$SOCK_DIR/fuse-output" 2>/dev/null)" != 2 
]; do
+            sleep 0.5
+
+            timeout=$((timeout - 1))
+            if [ "$timeout" = 0 ]; then
+                kill -SIGTERM $pid
+                echo 'Failed to set up FUSE export:' >&2
+                cat "$SOCK_DIR/fuse-output" >&2
+                rm -f "$export_mp"
+                break
+            fi
+        done
+        rm -f "$SOCK_DIR/fuse-output"
+
+        if [ "$timeout" -gt 0 ]; then
+            FUSE_PIDS+=($pid)
+            FUSE_EXPORTS+=("$export_mp")
+        fi
+    fi
+
     # Start QNIO server on image directory for vxhs protocol
     if [ $IMGPROTO = "vxhs" ]; then
         eval "$QEMU_VXHS -d  $TEST_DIR > /dev/null &"
@@ -447,6 +527,63 @@ _make_test_img()
 _rm_test_img()
 {
     local img=$1
+
+    if [[ $IMGPROTO == fuse && $img == $SOCK_DIR/fuse-* ]]; then
+        # Drop a FUSE export
+        local df_output
+        local i
+        local image_file
+        local index=''
+        local timeout
+
+        for i in "${!FUSE_EXPORTS[@]}"; do
+            if [ "${FUSE_EXPORTS[i]}" = "$img" ]; then
+                index=$i
+                break
+            fi
+        done
+
+        if [ -z "$index" ]; then
+            # Probably gone already
+            return 0
+        fi
+
+        kill "${FUSE_PIDS[index]}"
+
+        # Wait until the mount is gone
+        timeout=10 # *0.5 s
+        while true; do
+            # Will show the mount point; if the mount is still there,
+            # it will be $img.
+            df_output=$(df -T "$img" 2>/dev/null)
+
+            # But df may also show an error ("Transpoint endpoint not
+            # connected"), so retry in such cases
+            if [ -n "$df_output" ]; then
+                if ! echo "$df_output" | grep -q "$img"; then
+                    break
+                fi
+            fi
+
+            sleep 0.5
+
+            timeout=$((timeout - 1))
+            if [ "$timeout" = 0 ]; then
+                echo 'Failed to take down FUSE export' >&2
+                return 1
+            fi
+        done
+
+        rm -f "$img"
+
+        unset "FUSE_PIDS[$index]"
+        unset "FUSE_EXPORTS[$index]"
+
+        image_file=$(echo "$img" | sed -e "s#$SOCK_DIR/fuse-#$TEST_DIR/#")
+        _rm_test_img "$image_file"
+        return
+    fi
+
     if [ "$IMGFMT" = "vmdk" ]; then
         # Remove all the extents for vmdk
         "$QEMU_IMG" info "$img" 2>/dev/null | grep 'filename:' | cut -f 2 -d: \
@@ -468,6 +605,16 @@ _cleanup_test_img()
             _stop_nbd_server
             rm -f "$TEST_IMG_FILE"
             ;;
+        fuse)
+            local mp
+
+            for mp in "${FUSE_EXPORTS[@]}"; do
+                _rm_test_img "$mp"
+            done
+
+            FUSE_PIDS=()
+            FUSE_EXPORTS=()
+            ;;
         vxhs)
             if [ -f "${TEST_DIR}/qemu-vxhs.pid" ]; then
                 local QEMU_VXHS_PID
@@ -544,6 +691,7 @@ _img_info()
         sed -e "s#$REMOTE_TEST_DIR#TEST_DIR#g" \
             -e "s#$IMGPROTO:$TEST_DIR#TEST_DIR#g" \
             -e "s#$TEST_DIR#TEST_DIR#g" \
+            -e "s#$SOCK_DIR/fuse-#TEST_DIR/#g" \
             -e "s#$IMGFMT#IMGFMT#g" \
             -e "/^disk size:/ D" \
             -e "/actual-size/ D" | \
-- 
2.23.0