[LibOS,Docs] Remove deprecated syntax for FS mount points

The following syntax was deprecated in Gramine v1.2:
- `fs.mount.[identifier].type`
- `fs.mount.[identifier].path`
- `fs.mount.[identifier].uri`

Now that the next version of Gramine will be v1.5, we can safely remove
this syntax.

This commit also drops the deprecated relative mount paths.

Signed-off-by: Kailun Qin <kailun.qin@intel.com>

Documentation/manifest-syntax.rst

@@ -964,18 +964,6 @@ See :ref:`vtune-sgx-profiling` for more information.
 Deprecated options
 ------------------
 
-FS mount points (deprecated syntax)
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-
-::
-
-   fs.mount.[identifier].type = "[chroot|...]"
-   fs.mount.[identifier].path = "[PATH]"
-   fs.mount.[identifier].uri  = "[URI]"
-
-This syntax used a TOML table schema with keys for each mount. It has been
-replaced with the ``fs.mounts`` TOML array.
-
 Experimental sysfs topology support
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 

libos/src/fs/libos_fs.c

@@ -249,16 +249,11 @@ static int mount_one_nonroot(toml_table_t* mount, const char* prefix) {
     }
 
     if (mount_path[0] != '/') {
-        /* FIXME: Relative paths are deprecated starting from Gramine v1.2, we can disallow them
-         * completely two versions after it. */
-        if (is_dot_or_dotdot(mount_path)) {
-            log_error("Mount points '.' and '..' are not allowed, use absolute paths instead.");
-            ret = -EINVAL;
-            goto out;
-        }
-        log_error("Detected deprecated syntax: '%s.path' (\"%s\") is not absolute. "
+        log_error("Relative mount path: '%s.path' (\"%s\") is disallowed! "
                   "Consider converting it to absolute by adding \"/\" at the beginning.",
                   prefix, mount_path);
+        ret = -EINVAL;
+        goto out;
     }
 
     if (!mount_type || !strcmp(mount_type, "chroot")) {
@@ -296,105 +291,6 @@ static int mount_one_nonroot(toml_table_t* mount, const char* prefix) {
     return ret;
 }
 
-/*
- * Mount filesystems using the deprecated TOML-table syntax.
- *
- * FIXME: This is deprecated starting from Gramine v1.2 and can be removed two versions after it.
- */
-static int mount_nonroot_from_toml_table(void) {
-    int ret = 0;
-
-    assert(g_manifest_root);
-    toml_table_t* manifest_fs = toml_table_in(g_manifest_root, "fs");
-    if (!manifest_fs)
-        return 0;
-
-    toml_table_t* manifest_fs_mounts = toml_table_in(manifest_fs, "mount");
-    if (!manifest_fs_mounts)
-        return 0;
-
-    ssize_t mounts_cnt = toml_table_ntab(manifest_fs_mounts);
-    if (mounts_cnt < 0)
-        return -EINVAL;
-    if (mounts_cnt == 0)
-        return 0;
-
-    log_error("Detected deprecated syntax: 'fs.mount'. Consider converting to the new array "
-              "syntax: 'fs.mounts = [{ type = \"chroot\", uri = \"...\", path = \"...\" }]'.");
-
-    /*
-     * *** Warning: A _very_ ugly hack below ***
-     *
-     * In the TOML-table syntax, the entries are not ordered, but Gramine actually relies on the
-     * specific mounting order (e.g. you can't mount /lib/asdf first and then /lib, but the other
-     * way around works). The problem is, that TOML structure is just a dictionary, so the order of
-     * keys is not preserved.
-     *
-     * To fix the issue, we use an ugly heuristic - we apply mounts sorted by the path length, which
-     * in most cases should result in a proper mount order.
-     *
-     * We do this in O(n^2) because we don't have a sort function, but that shouldn't be an issue -
-     * usually there are around 5 mountpoints with ~30 chars in paths, so it should still be quite
-     * fast.
-     *
-     * Fortunately, the table syntax is deprecated, so we'll be able to remove this code in a future
-     * Gramine release.
-     *
-     * Corresponding issue: https://github.com/gramineproject/gramine/issues/23.
-     */
-    const char** keys = malloc(mounts_cnt * sizeof(*keys));
-    if (!keys)
-        return -ENOMEM;
-
-    size_t* lengths = malloc(mounts_cnt * sizeof(*lengths));
-    if (!lengths) {
-        ret = -ENOMEM;
-        goto out;
-    }
-
-    size_t longest = 0;
-    for (ssize_t i = 0; i < mounts_cnt; i++) {
-        keys[i] = toml_key_in(manifest_fs_mounts, i);
-        assert(keys[i]);
-
-        toml_table_t* mount = toml_table_in(manifest_fs_mounts, keys[i]);
-        assert(mount);
-        char* mount_path;
-        ret = toml_string_in(mount, "path", &mount_path);
-        if (ret < 0 || !mount_path) {
-            if (!ret)
-                ret = -ENOENT;
-            goto out;
-        }
-        lengths[i] = strlen(mount_path);
-        longest = MAX(longest, lengths[i]);
-        free(mount_path);
-    }
-
-    for (size_t i = 0; i <= longest; i++) {
-        for (ssize_t j = 0; j < mounts_cnt; j++) {
-            if (lengths[j] != i)
-                continue;
-            toml_table_t* mount = toml_table_in(manifest_fs_mounts, keys[j]);
-            assert(mount);
-
-            char* prefix = alloc_concat("fs.mount.", -1, keys[j], -1);
-            if (!prefix) {
-                ret = -ENOMEM;
-                goto out;
-            }
-            ret = mount_one_nonroot(mount, prefix);
-            free(prefix);
-            if (ret < 0)
-                goto out;
-        }
-    }
-out:
-    free(keys);
-    free(lengths);
-    return ret;
-}
-
 static int mount_nonroot_from_toml_array(void) {
     int ret;
 
@@ -466,10 +362,6 @@ int init_mount(void) {
 
     int ret;
 
-    ret = mount_nonroot_from_toml_table();
-    if (ret < 0)
-        return ret;
-
     ret = mount_nonroot_from_toml_array();
     if (ret < 0)
         return ret;

libos/test/regression/toml_parsing.manifest.template

@@ -7,16 +7,10 @@ libos.entrypoint = "{{ entrypoint }}"
 
 loader.env.LD_LIBRARY_PATH = "/lib"
 
-# keep the deprecated `fs.mount` syntax for test purposes
-# TODO: this syntax is deprecated in v1.2 and will be removed two versions after it.
-
-fs.mount.lib.type = "chroot"
-fs.mount.lib.path = "/lib"
-fs.mount.lib.uri = "file:{{ gramine.runtimedir(libc) }}"
-
-fs.mount.entrypoint.type = "chroot"
-fs.mount.entrypoint.path = "{{ entrypoint }}"
-fs.mount.entrypoint.uri = "file:{{ binary_dir }}/{{ entrypoint }}"
+fs.mounts = [
+  { path = "/lib", uri = "file:{{ gramine.runtimedir(libc) }}" },
+  { path = "/{{ entrypoint }}", uri = "file:{{ binary_dir }}/{{ entrypoint }}" },
+]
 
 # the manifest option below added only so that this feature has any test coverage
 libos.check_invalid_pointers = false