CI: Add simplefs test cases

Note:
- 7z does not recognize the simplefs format, thus verifying the written
  files in guestOS's stdout instead of using 7z l in hostOS.
- simplefs CI test cases does not run on macOS runner because the
  mkfs.simplefs cannot be compiled on macOS runner due to platform-
  specific header(<linux/fs.h>) is included at mkfs.c. [1]
  Before patching the simplefs upstream, skip the macOS runner for now.

[1] https://github.com/sysprog21/simplefs/blob/d7e0c9b6c1e09343ed862c709d3258c22f4a9a83/mkfs.c#L2

Author: ChinYikMing

.ci/boot-linux-prepare.sh

@@ -6,7 +6,15 @@ SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
 
 check_platform
 
-VBLK_IMG=build/disk.img
+VBLK_IMGS=(
+    build/disk_ext4.img
+)
+# FIXME: mkfs.simplefs is not compilable on macOS, thus running the
+# simplefs cases on Linux runner for now
+if [[ "${OS_TYPE}" == "Linux" ]]; then
+    VBLK_IMGS+=(build/disk_simplefs.img)
+fi
+
 which dd > /dev/null 2>&1 || {
     echo "Error: dd not found"
     exit 1
@@ -25,48 +33,77 @@ ACTION=$1
 
 case "$ACTION" in
     setup)
-        # Setup a disk image
-        dd if=/dev/zero of=${VBLK_IMG} bs=4M count=32
+        # Clone simplefs to use mkfs.simplefs util and create simplefs disk image
+        git clone https://github.com/sysprog21/simplefs.git -b rel2025.0 --depth 1
 
-        # Setup a /dev/ block device with ${VBLK_IMG} to test guestOS access to hostOS /dev/ block device
-        case "${OS_TYPE}" in
-            Linux)
-                mkfs.ext4 ${VBLK_IMG}
-                BLK_DEV=$(losetup -f)
-                losetup ${BLK_DEV} ${VBLK_IMG}
-                ;;
-            Darwin)
-                $(brew --prefix e2fsprogs)/sbin/mkfs.ext4 ${VBLK_IMG}
-                BLK_DEV=$(hdiutil attach -nomount ${VBLK_IMG})
-                ;;
-        esac
+        # Setup disk images
+        for disk_img in "${VBLK_IMGS[@]}"; do
+            case "${OS_TYPE}" in
+                Linux)
+                    # Setup a /dev/ block device with ext4 fs to test guestOS access to hostOS /dev/ block device
+                    if [[ "${disk_img}" =~ ext4 ]]; then
+                        dd if=/dev/zero of=${disk_img} bs=4M count=32
+                        mkfs.ext4 ${disk_img}
+                    else
+                        mkdir -p simplefs/build
+                        make IMAGE=${disk_img} ${disk_img} -C simplefs
+                        mv simplefs/${disk_img} ./build
+                    fi
+                    BLK_DEV=$(losetup -f)
+                    losetup ${BLK_DEV} ${disk_img}
+                    ;;
+                Darwin)
+                    # Setup a /dev/ block device with ext4 fs to test guestOS access to hostOS /dev/ block device
+                    dd if=/dev/zero of=${disk_img} bs=4M count=32
+                    $(brew --prefix e2fsprogs)/sbin/mkfs.ext4 ${disk_img}
+                    BLK_DEV=$(hdiutil attach -nomount ${disk_img})
+                    ;;
+            esac
 
-        # On Linux, ${VBLK_IMG} will be created by root and owned by root:root.
-        # Even if "others" have read and write (rw) permissions, accessing the file for certain operations may
-        # still require elevated privileges (e.g., setuid).
-        # To simplify this, we change the ownership to a non-root user.
-        # Use this with caution—changing ownership to runner:runner is specific to the GitHub CI environment.
-        chown runner: ${VBLK_IMG}
-        # Add other's rw permission to the disk image and device, so non-superuser can rw them
-        chmod o+r,o+w ${VBLK_IMG}
-        chmod o+r,o+w ${BLK_DEV}
+            # On Linux, ${disk_img} will be created by root and owned by root:root.
+            # Even if "others" have read and write (rw) permissions, accessing the file for certain operations may
+            # still require elevated privileges (e.g., setuid).
+            # To simplify this, we change the ownership to a non-root user.
+            # Use this with caution—changing ownership to runner:runner is specific to the GitHub CI environment.
+            chown runner: ${disk_img}
+            # Add other's rw permission to the disk image and device, so non-superuser can rw them
+            chmod o+r,o+w ${disk_img}
+            chmod o+r,o+w ${BLK_DEV}
 
-        # Export ${BLK_DEV} to a tmp file. Then, source to "$GITHUB_ENV" in job step.
-        echo "export BLK_DEV=${BLK_DEV}" > "${TMP_FILE}"
+            # Export ${BLK_DEV} to a tmp file. Then, source to "$GITHUB_ENV" in job step.
+            if [[ "${disk_img}" =~ ext4 ]]; then
+                echo "export BLK_DEV_EXT4=${BLK_DEV}" >> "${TMP_FILE}"
+            else
+                echo "export BLK_DEV_SIMPLEFS=${BLK_DEV}" >> "${TMP_FILE}"
+            fi
+        done
+
+        # Put simplefs.ko into ext4 fs
+        mkdir -p mnt
+        mount ${VBLK_IMGS[0]} mnt
+        cp build/linux-image/simplefs.ko mnt
+        umount mnt
+        rm -rf mnt
         ;;
     cleanup)
+        # Remove simplefs repo
+        rm -rf simplefs
+
         # Detach the /dev/loopx(Linux) or /dev/diskx(Darwin)
         case "${OS_TYPE}" in
             Linux)
-                losetup -d ${BLK_DEV}
+                losetup -d ${BLK_DEV_EXT4}
+                losetup -d ${BLK_DEV_SIMPLEFS}
                 ;;
             Darwin)
-                hdiutil detach ${BLK_DEV}
+                hdiutil detach ${BLK_DEV_EXT4}
                 ;;
         esac
 
-        # delete disk image
-        rm -f ${VBLK_IMG}
+        # delete disk images
+        for disk_img in "${VBLK_IMGS[@]}"; do
+            rm -f ${disk_img}
+        done
 
         # delete tmp file
         rm "${TMP_FILE}"