efi_loader: comments for efi_file_from_path()

Add more comments for efi_file_from_path().

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>

diff --git a/lib/efi_loader/efi_file.c b/lib/efi_loader/efi_file.c
index 4b4422205dd9ce0c5022e4a8bd77ec671b1e56fb..3a7323765bdb99318c3e326019c1b08f8bf09bad 100644 (file)
--- a/lib/efi_loader/efi_file.c
+++ b/lib/efi_loader/efi_file.c
@@ -641,6 +641,12 @@ static const struct efi_file_handle efi_file_handle_protocol = {
        .flush = efi_file_flush,
 };
 
+/**
+ * efi_file_from_path() - open file via device path
+ *
+ * @fp:                device path
+ * @return:    EFI_FILE_PROTOCOL for the file or NULL
+ */
 struct efi_file_handle *efi_file_from_path(struct efi_device_path *fp)
 {
        struct efi_simple_file_system_protocol *v;
@@ -655,10 +661,14 @@ struct efi_file_handle *efi_file_from_path(struct efi_device_path *fp)
        if (ret != EFI_SUCCESS)
                return NULL;
 
-       /* skip over device-path nodes before the file path: */
+       /* Skip over device-path nodes before the file path. */
        while (fp && !EFI_DP_TYPE(fp, MEDIA_DEVICE, FILE_PATH))
                fp = efi_dp_next(fp);
 
+       /*
+        * Step through the nodes of the directory path until the actual file
+        * node is reached which is the final node in the device path.
+        */
        while (fp) {
                struct efi_device_path_file_path *fdp =
                        container_of(fp, struct efi_device_path_file_path, dp);