bootconfig: Add xbc_get_info() for the node information

Add xbc_get_info() API which allows user to get the
number of used xbc_nodes and the size of bootconfig
data. This is also useful for checking the bootconfig
is initialized or not.

Link: https://lkml.kernel.org/r/163177340877.682366.4360676589783197627.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

diff --git a/include/linux/bootconfig.h b/include/linux/bootconfig.h
index 62e09b788172f2e783884ede3355b1f3b80f4d79..f955bb7eabbb34729de6301ad0c90b0d4e875927 100644 (file)
--- a/include/linux/bootconfig.h
+++ b/include/linux/bootconfig.h
@@ -273,6 +273,8 @@ static inline int __init xbc_node_compose_key(struct xbc_node *node,
 /* XBC node initializer */
 int __init xbc_init(const char *buf, size_t size, const char **emsg, int *epos);
 
+/* XBC node and size information */
+int __init xbc_get_info(int *node_size, size_t *data_size);
 
 /* XBC cleanup data structures */
 void __init xbc_destroy_all(void);

diff --git a/init/main.c b/init/main.c
index d894989d86bcd3981573c489410c0286a1154d3e..afaed805de195b65b5ecb229b8270b4216557c27 100644 (file)
--- a/init/main.c
+++ b/init/main.c
@@ -450,6 +450,7 @@ static void __init setup_boot_config(void)
                        pr_err("Failed to parse bootconfig: %s at %d.\n",
                                msg, pos);
        } else {
+               xbc_get_info(&ret, NULL);
                pr_info("Load bootconfig: %d bytes %d nodes\n", size, ret);
                /* keys starting with "kernel." are passed via cmdline */
                extra_command_line = xbc_make_cmdline("kernel");

diff --git a/lib/bootconfig.c b/lib/bootconfig.c
index 66b02fddfea8d00bd7a09523ec023432ff722fc7..b088fe5c0001cd24ca9f162283cb189f45b5a331 100644 (file)
--- a/lib/bootconfig.c
+++ b/lib/bootconfig.c
@@ -34,6 +34,27 @@ static int xbc_err_pos __initdata;
 static int open_brace[XBC_DEPTH_MAX] __initdata;
 static int brace_index __initdata;
 
+/**
+ * xbc_get_info() - Get the information of loaded boot config
+ * node_size: A pointer to store the number of nodes.
+ * data_size: A pointer to store the size of bootconfig data.
+ *
+ * Get the number of used nodes in @node_size if it is not NULL,
+ * and the size of bootconfig data in @data_size if it is not NULL.
+ * Return 0 if the boot config is initialized, or return -ENODEV.
+ */
+int __init xbc_get_info(int *node_size, size_t *data_size)
+{
+       if (!xbc_data)
+               return -ENODEV;
+
+       if (node_size)
+               *node_size = xbc_node_num;
+       if (data_size)
+               *data_size = xbc_data_size;
+       return 0;
+}
+
 static int __init xbc_parse_error(const char *msg, const char *p)
 {
        xbc_err_msg = msg;

diff --git a/tools/bootconfig/main.c b/tools/bootconfig/main.c
index 7269c9e35335f53fc20c7b979c833812d4482740..4f2a8d88474557f005b2a56409191c5431fe9b56 100644 (file)
--- a/tools/bootconfig/main.c
+++ b/tools/bootconfig/main.c
@@ -391,6 +391,7 @@ static int apply_xbc(const char *path, const char *xbc_path)
                return ret;
        }
        printf("Apply %s to %s\n", xbc_path, path);
+       xbc_get_info(&ret, NULL);
        printf("\tNumber of nodes: %d\n", ret);
        printf("\tSize: %u bytes\n", (unsigned int)size);
        printf("\tChecksum: %d\n", (unsigned int)csum);