[PATCH] run.py: add support of mounting directory via virtiofs device

[Waldemar Kozaczuk]

This patch adds two new options - '-virtio-fs-tag myfs' and '--virtio-fs-dir' -
that allow mounting directory via virtiofs device (which requires qemu >= 4.2).
When '--virtio-fs-dir' passed, run.py will also try to start virtiofsd daemon
provided it can be found in PATH.

Here is an example of using this new option:

./scripts/run.py -k --qemu-path=/home/wkozaczuk/projects/qemu/build/x86_64-softmmu/qemu-system-x86_64 --virtio-fs-tag myfs --virtio-fs-dir /home/wkozaczuk/projects/osv/apps/native-example -e '--mount-fs=virtiofs,/dev/virtiofs1,/tmp/virtiofs /tmp/virtiofs/hello' -V

Signed-off-by: Waldemar Kozaczuk <jwkoz...@gmail.com>
---
scripts/run.py | 26 ++++++++++++++++++++++++++
1 file changed, 26 insertions(+)

diff --git a/scripts/run.py b/scripts/run.py
index 95cca87b..9e2ed146 100755
--- a/scripts/run.py
+++ b/scripts/run.py
@@ -172,6 +172,13 @@ def start_osv_qemu(options):
"-device", "virtio-blk-pci,id=blk1,bootindex=1,drive=hd1,scsi=off%s" % options.virtio_device_suffix,
"-drive", "file=%s,if=none,id=hd1" % (options.cloud_init_image)]

+ if options.virtio_fs_tag:
+ args += [
+ "-chardev", "socket,id=char0,path=/tmp/vhostqemu",
+ "-device", "vhost-user-fs-pci,queue-size=1024,chardev=char0,tag=%s" % options.virtio_fs_tag,
+ "-object", "memory-backend-file,id=mem,size=%s,mem-path=/dev/shm,share=on" % options.memsize,
+ "-numa", "node,memdev=mem"]
+
if options.no_shutdown:
args += ["-no-reboot", "-no-shutdown"]

@@ -245,6 +252,18 @@ def start_osv_qemu(options):
for a in options.pass_args or []:
args += a.split()

+ if options.virtio_fs_dir:
+ try:
+ # Normally virtiofsd exits by itself but in future we should probably kill it if it did not
+ subprocess.Popen(["virtiofsd", "--socket-path=/tmp/vhostqemu", "-o",
+ "source=%s" % options.virtio_fs_dir, "-o", "cache=always"], stdout=devnull, stderr=devnull)
+ except OSError as e:
+ if e.errno == errno.ENOENT:
+ print("virtiofsd binary not found. Please install the qemu-system-x86 package that comes with it (>= 4.2) and is in path.")
+ else:
+ print("OS error({0}): \"{1}\" while running virtiofsd {2}".
+ format(e.errno, e.strerror, " ".join(args)))
+
try:
# Save the current settings of the stty
stty_save()
@@ -558,6 +577,10 @@ if __name__ == "__main__":
help="specify virtio version: legacy, transitional or modern")
parser.add_argument("--arch", action="store", choices=["x86_64","aarch64"], default="x86_64",
help="specify QEMU architecture: x86_64, aarch64")
+ parser.add_argument("--virtio-fs-tag", action="store",
+ help="virtio-fs device tag")
+ parser.add_argument("--virtio-fs-dir", action="store",
+ help="path to the directory exposed via virtio-fs mount")
cmdargs = parser.parse_args()
cmdargs.opt_path = "debug" if cmdargs.debug else "release" if cmdargs.release else "last"
cmdargs.image_file = os.path.abspath(cmdargs.image or os.path.join(osv_base, "build/%s/usr.img" % cmdargs.opt_path))
@@ -572,6 +595,9 @@ if __name__ == "__main__":
if not os.path.exists(cmdargs.cloud_init_image):
raise Exception('Cloud-init image %s does not exist.' % cmdargs.cloud_init_image)

+ if cmdargs.virtio_fs_dir and not os.path.exists(cmdargs.virtio_fs_dir):
+ raise Exception('Directory %s to be exposed through virtio-fs does not exist.' % cmdargs.virtio_fs_dir)
+
if cmdargs.hypervisor == "auto":
cmdargs.hypervisor = choose_hypervisor(cmdargs.networking,cmdargs.arch)

--
2.20.1

[Commit Bot]

From: Waldemar Kozaczuk <jwkoz...@gmail.com>
Committer: Waldemar Kozaczuk <jwkoz...@gmail.com>
Branch: master

run.py: add support of mounting directory via virtiofs device

This patch adds two new options - '-virtio-fs-tag myfs' and '--virtio-fs-dir' -
that allow mounting directory via virtiofs device (which requires qemu >= 4.2).
When '--virtio-fs-dir' passed, run.py will also try to start virtiofsd daemon
provided it can be found in PATH.

Here is an example of using this new option:

./scripts/run.py -k --qemu-path=/home/wkozaczuk/projects/qemu/build/x86_64-softmmu/qemu-system-x86_64 --virtio-fs-tag myfs --virtio-fs-dir /home/wkozaczuk/projects/osv/apps/native-example -e '--mount-fs=virtiofs,/dev/virtiofs1,/tmp/virtiofs /tmp/virtiofs/hello' -V

Signed-off-by: Waldemar Kozaczuk <jwkoz...@gmail.com>

---

diff --git a/scripts/run.py b/scripts/run.py

@@ -558,6 +577,10 @@ def main(options):

help="specify virtio version: legacy, transitional or modern")
parser.add_argument("--arch", action="store", choices=["x86_64","aarch64"], default="x86_64",
help="specify QEMU architecture: x86_64, aarch64")
+ parser.add_argument("--virtio-fs-tag", action="store",
+ help="virtio-fs device tag")
+ parser.add_argument("--virtio-fs-dir", action="store",
+ help="path to the directory exposed via virtio-fs mount")
cmdargs = parser.parse_args()
cmdargs.opt_path = "debug" if cmdargs.debug else "release" if cmdargs.release else "last"
cmdargs.image_file = os.path.abspath(cmdargs.image or os.path.join(osv_base, "build/%s/usr.img" % cmdargs.opt_path))

@@ -572,6 +595,9 @@ def main(options):