Introduce Virtio-loopback epsilon release:

Epsilon release introduces a new compatibility layer which make virtio-loopback
design to work with QEMU and rust-vmm vhost-user backend without require any
changes.

Signed-off-by: Timos Ampelikiotis <t.ampelikiotis@virtualopensystems.com>
Change-Id: I52e57563e08a7d0bdc002f8e928ee61ba0c53dd9

4 files changed, 341 insertions, 0 deletions

diff --git a/tests/avocado/virtiofs_submounts.py.data/cleanup.sh b/tests/avocado/virtiofs_submounts.py.data/cleanup.sh
new file mode 100644
index 000000000..2a6579a0f
--- /dev/null
+++ b/tests/avocado/virtiofs_submounts.py.data/cleanup.sh
@@ -0,0 +1,46 @@
+#!/bin/bash
+
+function print_usage()
+{
+    if [ -n "$2" ]; then
+        echo "Error: $2"
+        echo
+    fi
+    echo "Usage: $1 <scratch dir>"
+}
+
+scratch_dir=$1
+if [ -z "$scratch_dir" ]; then
+    print_usage "$0" 'Scratch dir not given' >&2
+    exit 1
+fi
+
+cd "$scratch_dir/share" || exit 1
+mps=(mnt*)
+mp_i=0
+for mp in "${mps[@]}"; do
+    mp_i=$((mp_i + 1))
+    printf "Unmounting %i/%i...\r" "$mp_i" "${#mps[@]}"
+
+    sudo umount -R "$mp"
+    rm -rf "$mp"
+done
+echo
+
+rm some-file
+cd ..
+rmdir share
+
+imgs=(fs*.img)
+img_i=0
+for img in "${imgs[@]}"; do
+    img_i=$((img_i + 1))
+    printf "Detaching and deleting %i/%i...\r" "$img_i" "${#imgs[@]}"
+
+    dev=$(losetup -j "$img" | sed -e 's/:.*//')
+    sudo losetup -d "$dev"
+    rm -f "$img"
+done
+echo
+
+echo 'Done.'
diff --git a/tests/avocado/virtiofs_submounts.py.data/guest-cleanup.sh b/tests/avocado/virtiofs_submounts.py.data/guest-cleanup.sh
new file mode 100644
index 000000000..729cb2d1a
--- /dev/null
+++ b/tests/avocado/virtiofs_submounts.py.data/guest-cleanup.sh
@@ -0,0 +1,30 @@
+#!/bin/bash
+
+function print_usage()
+{
+    if [ -n "$2" ]; then
+        echo "Error: $2"
+        echo
+    fi
+    echo "Usage: $1 <scratch dir>"
+}
+
+scratch_dir=$1
+if [ -z "$scratch_dir" ]; then
+    print_usage "$0" 'Scratch dir not given' >&2
+    exit 1
+fi
+
+cd "$scratch_dir/share" || exit 1
+
+mps=(mnt*)
+mp_i=0
+for mp in "${mps[@]}"; do
+    mp_i=$((mp_i + 1))
+    printf "Unmounting %i/%i...\r" "$mp_i" "${#mps[@]}"
+
+    sudo umount -R "$mp"
+done
+echo
+
+echo 'Done.'
diff --git a/tests/avocado/virtiofs_submounts.py.data/guest.sh b/tests/avocado/virtiofs_submounts.py.data/guest.sh
new file mode 100644
index 000000000..59ba40fde
--- /dev/null
+++ b/tests/avocado/virtiofs_submounts.py.data/guest.sh
@@ -0,0 +1,138 @@
+#!/bin/bash
+
+function print_usage()
+{
+    if [ -n "$2" ]; then
+        echo "Error: $2"
+        echo
+    fi
+    echo "Usage: $1 <shared dir>"
+    echo '(The shared directory is the "share" directory in the scratch' \
+         'directory)'
+}
+
+shared_dir=$1
+if [ -z "$shared_dir" ]; then
+    print_usage "$0" 'Shared dir not given' >&2
+    exit 1
+fi
+
+cd "$shared_dir"
+
+# FIXME: This should not be necessary, but it is.  In order for all
+# submounts to be proper mount points, we need to visit them.
+# (Before we visit them, they will not be auto-mounted, and so just
+# appear as normal directories, with the catch that their st_ino will
+# be the st_ino of the filesystem they host, while the st_dev will
+# still be the st_dev of the parent.)
+# `find` does not work, because it will refuse to touch the mount
+# points as long as they are not mounted; their st_dev being shared
+# with the parent and st_ino just being the root node's inode ID
+# will practically ensure that this node exists elsewhere on the
+# filesystem, and `find` is required to recognize loops and not to
+# follow them.
+# Thus, we have to manually visit all nodes first.
+
+mnt_i=0
+
+function recursively_visit()
+{
+    pushd "$1" >/dev/null
+    for entry in *; do
+        if [[ "$entry" == mnt* ]]; then
+            mnt_i=$((mnt_i + 1))
+            printf "Triggering auto-mount $mnt_i...\r"
+        fi
+
+        if [ -d "$entry" ]; then
+            recursively_visit "$entry"
+        fi
+    done
+    popd >/dev/null
+}
+
+recursively_visit .
+echo
+
+
+if [ -n "$(find -name not-mounted)" ]; then
+    echo "Error: not-mounted files visible on mount points:" >&2
+    find -name not-mounted >&2
+    exit 1
+fi
+
+if [ ! -f some-file -o "$(cat some-file)" != 'root' ]; then
+    echo "Error: Bad file in the share root" >&2
+    exit 1
+fi
+
+shopt -s nullglob
+
+function check_submounts()
+{
+    local base_path=$1
+
+    for mp in mnt*; do
+        printf "Checking submount %i...\r" "$((${#devs[@]} + 1))"
+
+        mp_i=$(echo "$mp" | sed -e 's/mnt//')
+        dev=$(stat -c '%D' "$mp")
+
+        if [ -n "${devs[mp_i]}" ]; then
+            echo "Error: $mp encountered twice" >&2
+            exit 1
+        fi
+        devs[mp_i]=$dev
+
+        pushd "$mp" >/dev/null
+        path="$base_path$mp"
+        while true; do
+            expected_content="$(printf '%s\n%s\n' "$mp_i" "$path")"
+            if [ ! -f some-file ]; then
+                echo "Error: $PWD/some-file does not exist" >&2
+                exit 1
+            fi
+
+            if [ "$(cat some-file)" != "$expected_content" ]; then
+                echo "Error: Bad content in $PWD/some-file:" >&2
+                echo '--- found ---'
+                cat some-file
+                echo '--- expected ---'
+                echo "$expected_content"
+                exit 1
+            fi
+            if [ "$(stat -c '%D' some-file)" != "$dev" ]; then
+                echo "Error: $PWD/some-file has the wrong device ID" >&2
+                exit 1
+            fi
+
+            if [ -d sub ]; then
+                if [ "$(stat -c '%D' sub)" != "$dev" ]; then
+                    echo "Error: $PWD/some-file has the wrong device ID" >&2
+                    exit 1
+                fi
+                cd sub
+                path="$path/sub"
+            else
+                if [ -n "$(echo mnt*)" ]; then
+                    check_submounts "$path/"
+                fi
+                break
+            fi
+        done
+        popd >/dev/null
+    done
+}
+
+root_dev=$(stat -c '%D' some-file)
+devs=()
+check_submounts ''
+echo
+
+reused_devs=$(echo "$root_dev ${devs[@]}" | tr ' ' '\n' | sort | uniq -d)
+if [ -n "$reused_devs" ]; then
+    echo "Error: Reused device IDs: $reused_devs" >&2
+    exit 1
+fi
+
+echo "Test passed for ${#devs[@]} submounts."
diff --git a/tests/avocado/virtiofs_submounts.py.data/host.sh b/tests/avocado/virtiofs_submounts.py.data/host.sh
new file mode 100644
index 000000000..d8a9afebd
--- /dev/null
+++ b/tests/avocado/virtiofs_submounts.py.data/host.sh
@@ -0,0 +1,127 @@
+#!/bin/bash
+
+mount_count=128
+
+function print_usage()
+{
+    if [ -n "$2" ]; then
+        echo "Error: $2"
+        echo
+    fi
+    echo "Usage: $1 <scratch dir> [seed]"
+    echo "(If no seed is given, it will be randomly generated.)"
+}
+
+scratch_dir=$1
+if [ -z "$scratch_dir" ]; then
+    print_usage "$0" 'No scratch dir given' >&2
+    exit 1
+fi
+
+if [ ! -d "$scratch_dir" ]; then
+    print_usage "$0" "$scratch_dir is not a directory" >&2
+    exit 1
+fi
+
+seed=$2
+if [ -z "$seed" ]; then
+    seed=$RANDOM
+fi
+RANDOM=$seed
+
+echo "Seed: $seed"
+
+set -e
+shopt -s nullglob
+
+cd "$scratch_dir"
+if [ -d share ]; then
+    echo 'Error: This directory seems to be in use already' >&2
+    exit 1
+fi
+
+for ((i = 0; i < $mount_count; i++)); do
+    printf "Setting up fs %i/%i...\r" "$((i + 1))" "$mount_count"
+
+    rm -f fs$i.img
+    truncate -s 512M fs$i.img
+    mkfs.xfs -q fs$i.img
+    devs[i]=$(sudo losetup -f --show fs$i.img)
+done
+echo
+
+top_level_mounts=$((RANDOM % mount_count + 1))
+
+mkdir -p share
+echo 'root' > share/some-file
+
+for ((i = 0; i < $top_level_mounts; i++)); do
+    printf "Mounting fs %i/%i...\r" "$((i + 1))" "$mount_count"
+
+    mkdir -p share/mnt$i
+    touch share/mnt$i/not-mounted
+    sudo mount "${devs[i]}" share/mnt$i
+    sudo chown "$(id -u):$(id -g)" share/mnt$i
+
+    pushd share/mnt$i >/dev/null
+    path=mnt$i
+    nesting=$((RANDOM % 4))
+    for ((j = 0; j < $nesting; j++)); do
+        cat > some-file <<EOF
+$i
+$path
+EOF
+        mkdir sub
+        cd sub
+        path="$path/sub"
+    done
+cat > some-file <<EOF
+$i
+$path
+EOF
+    popd >/dev/null
+done
+
+for ((; i < $mount_count; i++)); do
+    printf "Mounting fs %i/%i...\r" "$((i + 1))" "$mount_count"
+
+    mp_i=$((i % top_level_mounts))
+
+    pushd share/mnt$mp_i >/dev/null
+    path=mnt$mp_i
+    while true; do
+        sub_mp="$(echo mnt*)"
+        if cd sub 2>/dev/null; then
+            path="$path/sub"
+        elif [ -n "$sub_mp" ] && cd "$sub_mp" 2>/dev/null; then
+            path="$path/$sub_mp"
+        else
+            break
+        fi
+    done
+    mkdir mnt$i
+    touch mnt$i/not-mounted
+    sudo mount "${devs[i]}" mnt$i
+    sudo chown "$(id -u):$(id -g)" mnt$i
+
+    cd mnt$i
+    path="$path/mnt$i"
+    nesting=$((RANDOM % 4))
+    for ((j = 0; j < $nesting; j++)); do
+        cat > some-file <<EOF
+$i
+$path
+EOF
+        mkdir sub
+        cd sub
+        path="$path/sub"
+    done
+    cat > some-file <<EOF
+$i
+$path
+EOF
+    popd >/dev/null
+done
+echo
+
+echo 'Done.'