Commit bde03c4c authored by Al Viro's avatar Al Viro
Browse files

ep_loop_check_proc(): saner calling conventions 



1) 'cookie' argument is unused; kill it.
2) 'priv' one is always an epoll struct file, and we only care
about its associated struct eventpoll; pass that instead.

Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent 6a3890c4

fs/eventpoll.c

+16 −22
Original line number Diff line number Diff line
@@ -1845,19 +1845,14 @@ static int ep_poll(struct eventpoll *ep, struct epoll_event __user *events, 
 *                      result in excessive stack usage).

 *

 * @priv: Pointer to the epoll file to be currently checked.

 * @cookie: Original cookie for this call. This is the top-of-the-chain epoll

 *          data structure pointer.

 * @call_nests: Current dept of the @ep_call_nested() call stack.

 * @depth: Current depth of the path being checked.

 *

 * Returns: Returns zero if adding the epoll @file inside current epoll

 *          structure @ep does not violate the constraints, or -1 otherwise.

 */

static int ep_loop_check_proc(void *priv, void *cookie, int depth)

static int ep_loop_check_proc(struct eventpoll *ep, int depth)

{

	int error = 0;

	struct file *file = priv;

	struct eventpoll *ep = file->private_data;

	struct eventpoll *ep_tovisit;

	struct rb_node *rbp;

	struct epitem *epi;
@@ -1866,15 +1861,14 @@ static int ep_loop_check_proc(void *priv, void *cookie, int depth) 
	for (rbp = rb_first_cached(&ep->rbr); rbp; rbp = rb_next(rbp)) {

		epi = rb_entry(rbp, struct epitem, rbn);

		if (unlikely(is_file_epoll(epi->ffd.file))) {

			struct eventpoll *ep_tovisit;

			ep_tovisit = epi->ffd.file->private_data;

			if (ep_tovisit->gen == loop_check_gen)

				continue;

			if (ep_tovisit == inserting_into || depth > EP_MAX_NESTS) {

			if (ep_tovisit == inserting_into || depth > EP_MAX_NESTS)

				error = -1;

			} else {

				error = ep_loop_check_proc(epi->ffd.file, ep_tovisit,

						   depth + 1);

			}

			else

				error = ep_loop_check_proc(ep_tovisit, depth + 1);

			if (error != 0)

				break;

		} else {
@@ -1899,20 +1893,20 @@ static int ep_loop_check_proc(void *priv, void *cookie, int depth) 
}



/**

 * ep_loop_check - Performs a check to verify that adding an epoll file (@file)

 *                 another epoll file (represented by @ep) does not create

 * ep_loop_check - Performs a check to verify that adding an epoll file (@to)

 *                 into another epoll file (represented by @from) does not create

 *                 closed loops or too deep chains.

 *

 * @ep: Pointer to the epoll private data structure.

 * @file: Pointer to the epoll file to be checked.

 * @from: Pointer to the epoll we are inserting into.

 * @to: Pointer to the epoll to be inserted.

 *

 * Returns: Returns zero if adding the epoll @file inside current epoll

 *          structure @ep does not violate the constraints, or -1 otherwise.

 * Returns: Returns zero if adding the epoll @to inside the epoll @from

 * does not violate the constraints, or -1 otherwise.

 */

static int ep_loop_check(struct eventpoll *ep, struct file *file)

static int ep_loop_check(struct eventpoll *ep, struct eventpoll *to)

{

	inserting_into = ep;

	return ep_loop_check_proc(file, ep, 0);

	return ep_loop_check_proc(to, 0);

}



static void clear_tfile_check_list(void)
@@ -2086,8 +2080,9 @@ int do_epoll_ctl(int epfd, int op, int fd, struct epoll_event *epds, 
			loop_check_gen++;

			full_check = 1;

			if (is_file_epoll(tf.file)) {

				tep = tf.file->private_data;

				error = -ELOOP;

				if (ep_loop_check(ep, tf.file) != 0)

				if (ep_loop_check(ep, tep) != 0)

					goto error_tgt_fput;

			} else {

				get_file(tf.file);
@@ -2098,7 +2093,6 @@ int do_epoll_ctl(int epfd, int op, int fd, struct epoll_event *epds, 
			if (error)

				goto error_tgt_fput;

			if (is_file_epoll(tf.file)) {

				tep = tf.file->private_data;

				error = epoll_mutex_lock(&tep->mtx, 1, nonblock);

				if (error) {

					mutex_unlock(&ep->mtx);