On Wed, 15 Sep 2021 22:19:52 +0900
Masami Hiramatsu <mhiramat@xxxxxxxxxx> wrote:
> @@ -810,6 +811,8 @@ void __init xbc_destroy_all(void)
> * In error cases, @emsg will be updated with an error message and
> * @epos will be updated with the error position which is the byte offset
> * of @buf. If the error is not a parser error, @epos will be -1.
> + * Note that the @buf ownership is transferred, so it will be freed
> + * in xbc_destroy_all().
> */
> int __init xbc_init(char *buf, const char **emsg, int *epos)
> {
I hate this "ownership transfer". Looking at the use case here:
init/main.c:
copy = memblock_alloc(size + 1, SMP_CACHE_BYTES);
if (!copy) {
pr_err("Failed to allocate memory for bootconfig\n");
return;
}
memcpy(copy, data, size);
copy[size] = '\0';
ret = xbc_init(copy, &msg, &pos);
if (ret < 0) {
Instead of having xbc_init() return the node count on success, how about
having it allocate the buffer to use and then return it?
That is, move the:
copy = memblock_alloc(size + 1, SMP_CACHE_BYTES);
if (!copy) {
pr_err("Failed to allocate memory for bootconfig\n");
return;
}
memcpy(copy, data, size);
copy[size] = '\0';
into xbc_init(), and have data, and size be passed to it.
Then, have it return the pointer of "copy" or NULL on error?
This will keep the semantics of xbc_* owning the buffer that gets
freed by the destroy.
The xbc_init() could also do the pr_info() that prints the bytes and
node count. There's no other reason to pass that node count to the
caller, is there?
-- Steve
