From: Alan Cox <alan@linux.intel.com>
Date: Fri, 30 Mar 2018 23:25:50 +0000 (+0100)
Subject: syscall_net: make close non blocking add a callback for reuse
X-Git-Url: https://git.ndcode.org/public/gitweb.cgi?a=commitdiff_plain;h=3ee7ac5ed3065ba95e04214d3b24961409940cf5;p=FUZIX.git

syscall_net: make close non blocking add a callback for reuse

The new mode is close() sends a message to ask the stack to clean up. The
socket ends up dead until the stack calls ack into closed() to say that the
resources are now free.
---

diff --git a/Kernel/include/netdev.h b/Kernel/include/netdev.h
index 77b590a4..9783e406 100644
--- a/Kernel/include/netdev.h
+++ b/Kernel/include/netdev.h
@@ -60,6 +60,8 @@ struct socket
 #define SS_CLOSEWAIT		9	/* Remote has closed */
 #define SS_CLOSING		10	/* Protocol close in progress */
 #define SS_CLOSED		11	/* Protocol layers done, not close()d */
+#define SS_DEAD			12	/* Closed byuser space but not yet
+					   free of any stack resources */
 	/* FIXME: need state for shutdown handling */
 	uint8_t s_data;			/* Socket we are an accept() for */
 	uint8_t s_error;
@@ -77,6 +79,7 @@ struct socket
 #define SI_EOF		8		/* At EOF */
 #define SI_THROTTLE	16		/* Transmit is throttled */
 	void *s_priv;			/* Private pointer for lower layers */
+	inoptr s_ino;			/* Inode back pointer */
 };
 
 #define NSOCKTYPE 3
@@ -127,3 +130,4 @@ extern struct socket *sock_find(uint8_t type, uint8_t sv, struct sockaddrs *sa);
 extern void sock_init(void);
 extern int sock_error(struct socket *s);
 extern struct netdevice net_dev;
+extern void sock_closed(struct socket *s);
diff --git a/Kernel/syscall_net.c b/Kernel/syscall_net.c
index 76b13fe1..2da8a0f4 100644
--- a/Kernel/syscall_net.c
+++ b/Kernel/syscall_net.c
@@ -130,12 +130,17 @@ void sock_close(inoptr ino)
 	/* For the moment */
 	struct socket *s = &sockets[ino->c_node.i_nlink];
 	net_close(s);
-	sock_wait_enter(s, 0, SS_CLOSED);
+	/* Dead but not unbound from netd activity yet */
+	s->s_state = SS_DEAD;
+}
+
+void sock_closed(struct socket *s)
+{
 	s->s_state = SS_UNUSED;
 	/* You re-use something you pays the price. Probably should switch
 	   to using data 0 as devices do ? FIXME */
-	ino->c_node.i_nlink = 0;
-	ino->c_flags |= CDIRTY;
+	s->s_ino->c_node.i_nlink = 0;
+	s->s_ino->c_flags |= CDIRTY;
 }
 
 /*
@@ -331,6 +336,8 @@ arg_t make_socket(struct sockinfo *s, struct socket **np)
 	ino->c_readers = 1;
 	ino->c_writers = 1;
 
+	n->s_ino = ino;
+
 	of_tab[oftindex].o_inode = ino;
 	of_tab[oftindex].o_access = O_RDWR;