From 96cf21fad06a18ca7d1550e740d3e6733e2bf3dc Mon Sep 17 00:00:00 2001 From: Zhongtao Hu Date: Tue, 20 Sep 2022 14:26:08 +0800 Subject: [PATCH] runtime-rs: add comments for runtime-rs shared directory add comments for runtime-rs shared directory Fixes:#5197 Signed-off-by: Zhongtao Hu --- .../crates/resource/src/share_fs/utils.rs | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) diff --git a/src/runtime-rs/crates/resource/src/share_fs/utils.rs b/src/runtime-rs/crates/resource/src/share_fs/utils.rs index 6399426b9b..97466cba65 100644 --- a/src/runtime-rs/crates/resource/src/share_fs/utils.rs +++ b/src/runtime-rs/crates/resource/src/share_fs/utils.rs @@ -41,9 +41,16 @@ pub(crate) fn share_to_guest( Ok(do_get_guest_path(target, cid, is_volume)) } - -pub(crate) fn get_host_ro_shared_path(sid: &str) -> PathBuf { - Path::new(KATA_HOST_SHARED_DIR).join(sid).join("ro") +// Shared path handling: +// 1. create two directories for each sandbox: +// -. /run/kata-containers/shared/sandboxes/$sbx_id/rw/, a host/guest shared directory which is rw +// -. /run/kata-containers/shared/sandboxes/$sbx_id/ro/, a host/guest shared directory (virtiofs source dir) which is ro +// +// 2. /run/kata-containers/shared/sandboxes/$sbx_id/rw/ is bind mounted readonly to /run/kata-containers/shared/sandboxes/$sbx_id/ro/, so guest cannot modify it +// +// 3. host-guest shared files/directories are mounted one-level under /run/kata-containers/shared/sandboxes/$sbx_id/rw/passthrough and thus present to guest at one level under run/kata-containers/shared/containers/passthrough. +pub(crate) fn get_host_ro_shared_path(id: &str) -> PathBuf { + Path::new(KATA_HOST_SHARED_DIR).join(id).join("ro") } pub(crate) fn get_host_rw_shared_path(sid: &str) -> PathBuf {