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-rw-r--r--net/unix/garbage.c70
1 files changed, 28 insertions, 42 deletions
diff --git a/net/unix/garbage.c b/net/unix/garbage.c
index 99f7012..a73a226 100644
--- a/net/unix/garbage.c
+++ b/net/unix/garbage.c
@@ -95,39 +95,36 @@ static DECLARE_WAIT_QUEUE_HEAD(unix_gc_wait);
unsigned int unix_tot_inflight;
-
struct sock *unix_get_socket(struct file *filp)
{
struct sock *u_sock = NULL;
struct inode *inode = file_inode(filp);
- /*
- * Socket ?
- */
+ /* Socket ? */
if (S_ISSOCK(inode->i_mode) && !(filp->f_mode & FMODE_PATH)) {
struct socket *sock = SOCKET_I(inode);
struct sock *s = sock->sk;
- /*
- * PF_UNIX ?
- */
+ /* PF_UNIX ? */
if (s && sock->ops && sock->ops->family == PF_UNIX)
u_sock = s;
}
return u_sock;
}
-/*
- * Keep the number of times in flight count for the file
- * descriptor if it is for an AF_UNIX socket.
+/* Keep the number of times in flight count for the file
+ * descriptor if it is for an AF_UNIX socket.
*/
void unix_inflight(struct file *fp)
{
struct sock *s = unix_get_socket(fp);
+
if (s) {
struct unix_sock *u = unix_sk(s);
+
spin_lock(&unix_gc_lock);
+
if (atomic_long_inc_return(&u->inflight) == 1) {
BUG_ON(!list_empty(&u->link));
list_add_tail(&u->link, &gc_inflight_list);
@@ -142,10 +139,13 @@ void unix_inflight(struct file *fp)
void unix_notinflight(struct file *fp)
{
struct sock *s = unix_get_socket(fp);
+
if (s) {
struct unix_sock *u = unix_sk(s);
+
spin_lock(&unix_gc_lock);
BUG_ON(list_empty(&u->link));
+
if (atomic_long_dec_and_test(&u->inflight))
list_del_init(&u->link);
unix_tot_inflight--;
@@ -161,32 +161,27 @@ static void scan_inflight(struct sock *x, void (*func)(struct unix_sock *),
spin_lock(&x->sk_receive_queue.lock);
skb_queue_walk_safe(&x->sk_receive_queue, skb, next) {
- /*
- * Do we have file descriptors ?
- */
+ /* Do we have file descriptors ? */
if (UNIXCB(skb).fp) {
bool hit = false;
- /*
- * Process the descriptors of this socket
- */
+ /* Process the descriptors of this socket */
int nfd = UNIXCB(skb).fp->count;
struct file **fp = UNIXCB(skb).fp->fp;
+
while (nfd--) {
- /*
- * Get the socket the fd matches
- * if it indeed does so
- */
+ /* Get the socket the fd matches if it indeed does so */
struct sock *sk = unix_get_socket(*fp++);
+
if (sk) {
struct unix_sock *u = unix_sk(sk);
- /*
- * Ignore non-candidates, they could
+ /* Ignore non-candidates, they could
* have been added to the queues after
* starting the garbage collection
*/
if (test_bit(UNIX_GC_CANDIDATE, &u->gc_flags)) {
hit = true;
+
func(u);
}
}
@@ -203,24 +198,22 @@ static void scan_inflight(struct sock *x, void (*func)(struct unix_sock *),
static void scan_children(struct sock *x, void (*func)(struct unix_sock *),
struct sk_buff_head *hitlist)
{
- if (x->sk_state != TCP_LISTEN)
+ if (x->sk_state != TCP_LISTEN) {
scan_inflight(x, func, hitlist);
- else {
+ } else {
struct sk_buff *skb;
struct sk_buff *next;
struct unix_sock *u;
LIST_HEAD(embryos);
- /*
- * For a listening socket collect the queued embryos
+ /* For a listening socket collect the queued embryos
* and perform a scan on them as well.
*/
spin_lock(&x->sk_receive_queue.lock);
skb_queue_walk_safe(&x->sk_receive_queue, skb, next) {
u = unix_sk(skb->sk);
- /*
- * An embryo cannot be in-flight, so it's safe
+ /* An embryo cannot be in-flight, so it's safe
* to use the list link.
*/
BUG_ON(!list_empty(&u->link));
@@ -249,8 +242,7 @@ static void inc_inflight(struct unix_sock *usk)
static void inc_inflight_move_tail(struct unix_sock *u)
{
atomic_long_inc(&u->inflight);
- /*
- * If this still might be part of a cycle, move it to the end
+ /* If this still might be part of a cycle, move it to the end
* of the list, so that it's checked even if it was already
* passed over
*/
@@ -263,8 +255,7 @@ static bool gc_in_progress;
void wait_for_unix_gc(void)
{
- /*
- * If number of inflight sockets is insane,
+ /* If number of inflight sockets is insane,
* force a garbage collect right now.
*/
if (unix_tot_inflight > UNIX_INFLIGHT_TRIGGER_GC && !gc_in_progress)
@@ -288,8 +279,7 @@ void unix_gc(void)
goto out;
gc_in_progress = true;
- /*
- * First, select candidates for garbage collection. Only
+ /* First, select candidates for garbage collection. Only
* in-flight sockets are considered, and from those only ones
* which don't have any external reference.
*
@@ -320,15 +310,13 @@ void unix_gc(void)
}
}
- /*
- * Now remove all internal in-flight reference to children of
+ /* Now remove all internal in-flight reference to children of
* the candidates.
*/
list_for_each_entry(u, &gc_candidates, link)
scan_children(&u->sk, dec_inflight, NULL);
- /*
- * Restore the references for children of all candidates,
+ /* Restore the references for children of all candidates,
* which have remaining references. Do this recursively, so
* only those remain, which form cyclic references.
*
@@ -350,8 +338,7 @@ void unix_gc(void)
}
list_del(&cursor);
- /*
- * not_cycle_list contains those sockets which do not make up a
+ /* not_cycle_list contains those sockets which do not make up a
* cycle. Restore these to the inflight list.
*/
while (!list_empty(&not_cycle_list)) {
@@ -360,8 +347,7 @@ void unix_gc(void)
list_move_tail(&u->link, &gc_inflight_list);
}
- /*
- * Now gc_candidates contains only garbage. Restore original
+ /* Now gc_candidates contains only garbage. Restore original
* inflight counters for these as well, and remove the skbuffs
* which are creating the cycle(s).
*/
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