Merge remote-tracking branch 'kiszka/queues/slirp' into staging

* kiszka/queues/slirp:
  slirp: Fix compiler warning for w64
  slirp: Cleanup resources on instance removal
  slirp: Remove unneeded if_queued
  slirp: Fix queue walking in if_start
  slirp: Prevent recursion of if_start
  slirp: Keep next_m always valid

slirp/cksum.c

@@ -75,7 +75,7 @@ int cksum(struct mbuf *m, int len)
 	/*
 	 * Force to even boundary.
 	 */
-	if ((1 & (long) w) && (mlen > 0)) {
+	if ((1 & (uintptr_t)w) && (mlen > 0)) {
 		REDUCE;
 		sum <<= 8;
 		s_util.c[0] = *(uint8_t *)w;

slirp/if.c

@@ -96,8 +96,13 @@ if_output(struct socket *so, struct mbuf *ifm)
 			ifs_insque(ifm, ifq->ifs_prev);
 			goto diddit;
 		}
-	} else
+        } else {
 		ifq = slirp->if_batchq.ifq_prev;
+                /* Set next_m if the queue was empty so far */
+                if (slirp->next_m == &slirp->if_batchq) {
+                    slirp->next_m = ifm;
+                }
+        }
 
 	/* Create a new doubly linked list for this session */
 	ifm->ifq_so = so;
@@ -105,8 +110,6 @@ if_output(struct socket *so, struct mbuf *ifm)
 	insque(ifm, ifq);
 
 diddit:
-	slirp->if_queued++;
-
 	if (so) {
 		/* Update *_queued */
 		so->so_queued++;
@@ -152,44 +155,54 @@ diddit:
 void if_start(Slirp *slirp)
 {
     uint64_t now = qemu_get_clock_ns(rt_clock);
-    int requeued = 0;
+    bool from_batchq, next_from_batchq;
-    bool from_batchq = false;
+    struct mbuf *ifm, *ifm_next, *ifqt;
-    struct mbuf *ifm, *ifqt;
 
     DEBUG_CALL("if_start");
 
-    while (slirp->if_queued) {
+    if (slirp->if_start_busy) {
+        return;
+    }
+    slirp->if_start_busy = true;
+
+    if (slirp->if_fastq.ifq_next != &slirp->if_fastq) {
+        ifm_next = slirp->if_fastq.ifq_next;
+        next_from_batchq = false;
+    } else if (slirp->next_m != &slirp->if_batchq) {
+        /* Nothing on fastq, pick up from batchq via next_m */
+        ifm_next = slirp->next_m;
+        next_from_batchq = true;
+    } else {
+        ifm_next = NULL;
+    }
+
+    while (ifm_next) {
         /* check if we can really output */
-        if (!slirp_can_output(slirp->opaque))
+        if (!slirp_can_output(slirp->opaque)) {
-            return;
+            break;
-
-        /*
-         * See which queue to get next packet from
-         * If there's something in the fastq, select it immediately
-         */
-        if (slirp->if_fastq.ifq_next != &slirp->if_fastq) {
-            ifm = slirp->if_fastq.ifq_next;
-        } else {
-            /* Nothing on fastq, see if next_m is valid */
-            if (slirp->next_m != &slirp->if_batchq) {
-                ifm = slirp->next_m;
-            } else {
-                ifm = slirp->if_batchq.ifq_next;
-            }
-
-            from_batchq = true;
         }
 
-        slirp->if_queued--;
+        ifm = ifm_next;
+        from_batchq = next_from_batchq;
+
+        ifm_next = ifm->ifq_next;
+        if (ifm_next == &slirp->if_fastq) {
+            /* No more packets in fastq, switch to batchq */
+            ifm_next = slirp->next_m;
+            next_from_batchq = true;
+        }
+        if (ifm_next == &slirp->if_batchq) {
+            /* end of batchq */
+            ifm_next = NULL;
+        }
 
         /* Try to send packet unless it already expired */
         if (ifm->expiration_date >= now && !if_encap(slirp, ifm)) {
             /* Packet is delayed due to pending ARP resolution */
-            requeued++;
             continue;
         }
 
-        if (from_batchq) {
+        if (ifm == slirp->next_m) {
             /* Set which packet to send on next iteration */
             slirp->next_m = ifm->ifq_next;
         }
@@ -200,8 +213,20 @@ void if_start(Slirp *slirp)
 
         /* If there are more packets for this session, re-queue them */
         if (ifm->ifs_next != ifm) {
-            insque(ifm->ifs_next, ifqt);
+            struct mbuf *next = ifm->ifs_next;
+
+            insque(next, ifqt);
             ifs_remque(ifm);
+
+            if (!from_batchq) {
+                /* Next packet in fastq is from the same session */
+                ifm_next = next;
+                next_from_batchq = false;
+            } else if (slirp->next_m == &slirp->if_batchq) {
+                /* Set next_m and ifm_next if the session packet is now the
+                 * only one on batchq */
+                slirp->next_m = ifm_next = next;
+            }
         }
 
         /* Update so_queued */
@@ -211,8 +236,7 @@ void if_start(Slirp *slirp)
         }
 
         m_free(ifm);
-
     }
 
-    slirp->if_queued = requeued;
+    slirp->if_start_busy = false;
 }

slirp/ip_icmp.c

@@ -66,6 +66,13 @@ void icmp_init(Slirp *slirp)
     slirp->icmp_last_so = &slirp->icmp;
 }
 
+void icmp_cleanup(Slirp *slirp)
+{
+    while (slirp->icmp.so_next != &slirp->icmp) {
+        icmp_detach(slirp->icmp.so_next);
+    }
+}
+
 static int icmp_send(struct socket *so, struct mbuf *m, int hlen)
 {
     struct ip *ip = mtod(m, struct ip *);

slirp/ip_icmp.h

@@ -154,6 +154,7 @@ struct icmp {
 	(type) == ICMP_MASKREQ || (type) == ICMP_MASKREPLY)
 
 void icmp_init(Slirp *slirp);
+void icmp_cleanup(Slirp *slirp);
 void icmp_input(struct mbuf *, int);
 void icmp_error(struct mbuf *msrc, u_char type, u_char code, int minsize,
                 const char *message);

slirp/ip_input.c

@@ -61,6 +61,13 @@ ip_init(Slirp *slirp)
     icmp_init(slirp);
 }
 
+void ip_cleanup(Slirp *slirp)
+{
+    udp_cleanup(slirp);
+    tcp_cleanup(slirp);
+    icmp_cleanup(slirp);
+}
+
 /*
  * Ip input routine.  Checksum and byte swap header.  If fragmented
  * try to reassemble.  Process options.  Pass to next level.

slirp/mbuf.c

@@ -32,6 +32,27 @@ m_init(Slirp *slirp)
     slirp->m_usedlist.m_next = slirp->m_usedlist.m_prev = &slirp->m_usedlist;
 }
 
+void m_cleanup(Slirp *slirp)
+{
+    struct mbuf *m, *next;
+
+    m = slirp->m_usedlist.m_next;
+    while (m != &slirp->m_usedlist) {
+        next = m->m_next;
+        if (m->m_flags & M_EXT) {
+            free(m->m_ext);
+        }
+        free(m);
+        m = next;
+    }
+    m = slirp->m_freelist.m_next;
+    while (m != &slirp->m_freelist) {
+        next = m->m_next;
+        free(m);
+        m = next;
+    }
+}
+
 /*
  * Get an mbuf from the free list, if there are none
  * malloc one

slirp/mbuf.h

@@ -116,6 +116,7 @@ struct mbuf {
 					 * it rather than putting it on the free list */
 
 void m_init(Slirp *);
+void m_cleanup(Slirp *slirp);
 struct mbuf * m_get(Slirp *);
 void m_free(struct mbuf *);
 void m_cat(register struct mbuf *, register struct mbuf *);

slirp/slirp.c

@@ -246,6 +246,9 @@ void slirp_cleanup(Slirp *slirp)
 
     unregister_savevm(NULL, "slirp", slirp);
 
+    ip_cleanup(slirp);
+    m_cleanup(slirp);
+
     g_free(slirp->tftp_prefix);
     g_free(slirp->bootp_filename);
     g_free(slirp);
@@ -581,12 +584,7 @@ void slirp_select_poll(fd_set *readfds, fd_set *writefds, fd_set *xfds,
                 }
 	}
 
-	/*
+        if_start(slirp);
-	 * See if we can start outputting
-	 */
-	if (slirp->if_queued) {
-	    if_start(slirp);
-	}
     }
 
 	/* clear global file descriptor sets.

slirp/slirp.h

@@ -235,10 +235,10 @@ struct Slirp {
     int mbuf_alloced;
 
     /* if states */
-    int if_queued;          /* number of packets queued so far */
     struct mbuf if_fastq;   /* fast queue (for interactive data) */
     struct mbuf if_batchq;  /* queue for non-interactive data */
     struct mbuf *next_m;    /* pointer to next mbuf to output */
+    bool if_start_busy;     /* avoid if_start recursion */
 
     /* ip states */
     struct ipq ipq;         /* ip reass. queue */
@@ -315,6 +315,7 @@ void if_output(struct socket *, struct mbuf *);
 
 /* ip_input.c */
 void ip_init(Slirp *);
+void ip_cleanup(Slirp *);
 void ip_input(struct mbuf *);
 void ip_slowtimo(Slirp *);
 void ip_stripoptions(register struct mbuf *, struct mbuf *);
@@ -332,6 +333,7 @@ void tcp_setpersist(register struct tcpcb *);
 
 /* tcp_subr.c */
 void tcp_init(Slirp *);
+void tcp_cleanup(Slirp *);
 void tcp_template(struct tcpcb *);
 void tcp_respond(struct tcpcb *, register struct tcpiphdr *, register struct mbuf *, tcp_seq, tcp_seq, int);
 struct tcpcb * tcp_newtcpcb(struct socket *);

slirp/tcp_subr.c

@@ -55,6 +55,13 @@ tcp_init(Slirp *slirp)
     slirp->tcp_last_so = &slirp->tcb;
 }
 
+void tcp_cleanup(Slirp *slirp)
+{
+    while (slirp->tcb.so_next != &slirp->tcb) {
+        tcp_close(sototcpcb(slirp->tcb.so_next));
+    }
+}
+
 /*
  * Create template to be used to send tcp packets on a connection.
  * Call after host entry created, fills

slirp/udp.c

@@ -49,6 +49,14 @@ udp_init(Slirp *slirp)
     slirp->udb.so_next = slirp->udb.so_prev = &slirp->udb;
     slirp->udp_last_so = &slirp->udb;
 }
+
+void udp_cleanup(Slirp *slirp)
+{
+    while (slirp->udb.so_next != &slirp->udb) {
+        udp_detach(slirp->udb.so_next);
+    }
+}
+
 /* m->m_data  points at ip packet header
  * m->m_len   length ip packet
  * ip->ip_len length data (IPDU)

slirp/udp.h

@@ -74,6 +74,7 @@ struct udpiphdr {
 struct mbuf;
 
 void udp_init(Slirp *);
+void udp_cleanup(Slirp *);
 void udp_input(register struct mbuf *, int);
 int udp_output(struct socket *, struct mbuf *, struct sockaddr_in *);
 int udp_attach(struct socket *);