[nvo] Allow fragment list to be omitted

Allow the fragment list to be omitted when calling nvo_init().
Omitting the list will cause the whole of the NVS device to be used
for NVO storage.

Signed-off-by: Michael Brown <mcb30@ipxe.org>

diff --git a/src/core/nvo.c b/src/core/nvo.c
index 327f4f9812bb591f2f6a6dbe82e006fa6759367d..00f2d9ffc305e6f497d480301b854d3c5ce44624 100644 (file)
--- a/src/core/nvo.c
+++ b/src/core/nvo.c
@@ -197,7 +197,7 @@ static struct settings_operations nvo_settings_operations = {
  *
  * @v nvo              Non-volatile options block
  * @v nvs              Underlying non-volatile storage device
- * @v fragments                List of option-containing fragments
+ * @v fragments                List of option-containing fragments, or NULL
  * @v refcnt           Containing object reference counter, or NULL
  */
 void nvo_init ( struct nvo_block *nvo, struct nvs_device *nvs,
@@ -219,18 +219,32 @@ int register_nvo ( struct nvo_block *nvo, struct settings *parent ) {
        struct nvo_fragment *fragment = nvo->fragments;
        int rc;
 
-       /* Calculate total length of all fragments */
-       for ( fragment = nvo->fragments ; fragment->len ; fragment++ )
-               nvo->total_len += fragment->len;
+       /* Calculate total length of all fragments, if applicable */
+       if ( fragment ) {
+               for ( ; fragment->len ; fragment++ )
+                       nvo->total_len += fragment->len;
+       } else {
+               nvo->total_len = nvo->nvs->size;
+       }
 
-       /* Allocate memory for options and read in from NVS */
-       nvo->data = malloc ( nvo->total_len );
+       /* Allocate memory for options (and fragment list, if applicable) */
+       nvo->data = zalloc ( nvo->total_len +
+                            ( fragment ? 0 : ( 2 * sizeof ( *fragment ) ) ) );
        if ( ! nvo->data ) {
                DBGC ( nvo, "NVO %p could not allocate %zd bytes\n",
                       nvo, nvo->total_len );
                rc = -ENOMEM;
                goto err_malloc;
        }
+
+       /* Create fragment list, if applicable */
+       if ( ! fragment ) {
+               fragment = ( nvo->data + nvo->total_len );
+               fragment->len = nvo->total_len;
+               nvo->fragments = fragment;
+       }
+
+       /* Read data from NVS */
        if ( ( rc = nvo_load ( nvo ) ) != 0 )
                goto err_load;