[retry] Hold reference while timer is running and during expiry callback

Guarantee that a retry timer cannot go out of scope while the timer is
running, and provide a guarantee to the expiry callback that the timer
will remain in scope during the entire callback (similar to the
guarantee provided to interface methods).

Signed-off-by: Michael Brown <mcb30@ipxe.org>

diff --git a/src/include/ipxe/retry.h b/src/include/ipxe/retry.h
index ff26de2529c7814c119eafdfe364cde4bb864938..d2ea27fb23d3e86ed4df947ad3e390e06b629462 100644 (file)
--- a/src/include/ipxe/retry.h
+++ b/src/include/ipxe/retry.h
@@ -49,6 +49,12 @@ struct retry_timer {
         * timeout has already exceeded @c MAX_TIMEOUT.
         */
        void ( * expired ) ( struct retry_timer *timer, int over );
+       /** Reference counter
+        *
+        * If this interface is not part of a reference-counted
+        * object, this field may be NULL.
+        */
+       struct refcnt *refcnt;
 };
 
 /**
@@ -56,11 +62,14 @@ struct retry_timer {
  *
  * @v timer            Retry timer
  * @v expired          Timer expired callback
+ * @v refcnt           Reference counter, or NULL
  */
 static inline __attribute__ (( always_inline )) void
 timer_init ( struct retry_timer *timer,
-            void ( * expired ) ( struct retry_timer *timer, int over ) ) {
+            void ( * expired ) ( struct retry_timer *timer, int over ),
+            struct refcnt *refcnt ) {
        timer->expired = expired;
+       timer->refcnt = refcnt;
 }
 
 extern void start_timer ( struct retry_timer *timer );

diff --git a/src/net/aoe.c b/src/net/aoe.c
index 4a03e2b647ecfe4ce37fc44b30720a891f1be621..5e1a3b5bd86e06a289951d8237f1384c3bb4ae9b 100644 (file)
--- a/src/net/aoe.c
+++ b/src/net/aoe.c
@@ -439,7 +439,7 @@ int aoe_attach ( struct ata_device *ata, struct net_device *netdev,
        if ( ! aoe )
                return -ENOMEM;
        ref_init ( &aoe->refcnt, aoe_free );
-       timer_init ( &aoe->timer, aoe_timer_expired );
+       timer_init ( &aoe->timer, aoe_timer_expired, &aoe->refcnt );
        aoe->netdev = netdev_get ( netdev );
        memcpy ( aoe->target, netdev->ll_broadcast, sizeof ( aoe->target ) );
        aoe->tag = AOE_TAG_MAGIC;

diff --git a/src/net/infiniband/ib_mi.c b/src/net/infiniband/ib_mi.c
index 5a01ce25052125b3c88561c3980cb1924e1676ab..8c15655fd2859eab629db5878ffcff302eb26741 100644 (file)
--- a/src/net/infiniband/ib_mi.c
+++ b/src/net/infiniband/ib_mi.c
@@ -281,7 +281,7 @@ ib_create_madx ( struct ib_device *ibdev, struct ib_mad_interface *mi,
        madx = zalloc ( sizeof ( *madx ) );
        if ( ! madx )
                return NULL;
-       timer_init ( &madx->timer, ib_mi_timer_expired );
+       timer_init ( &madx->timer, ib_mi_timer_expired, NULL );
        madx->mi = mi;
        madx->op = op;
 

diff --git a/src/net/ipv4.c b/src/net/ipv4.c
index a3cbdb03935df5556b96030687357245a395ca3f..5918bbecf5e6b26504725029ae48d059837989ea 100644 (file)
--- a/src/net/ipv4.c
+++ b/src/net/ipv4.c
@@ -222,7 +222,7 @@ static struct io_buffer * ipv4_reassemble ( struct io_buffer * iobuf ) {
                free_iob ( iobuf );
 
                /* Set the reassembly timer */
-               timer_init ( &fragbuf->frag_timer, ipv4_frag_expired );
+               timer_init ( &fragbuf->frag_timer, ipv4_frag_expired, NULL );
                start_timer_fixed ( &fragbuf->frag_timer, IP_FRAG_TIMEOUT );
 
                /* Add the fragment buffer to the list of fragment buffers */

diff --git a/src/net/retry.c b/src/net/retry.c
index 5eefa3d48816c8711419a6b480739951d1aa6649..b65bb57e0577382e87d2d354b6579f710ec75789 100644 (file)
--- a/src/net/retry.c
+++ b/src/net/retry.c
@@ -57,8 +57,10 @@ static LIST_HEAD ( timers );
  * be stopped and the timer's callback function will be called.
  */
 void start_timer ( struct retry_timer *timer ) {
-       if ( ! timer->running )
+       if ( ! timer->running ) {
                list_add ( &timer->list, &timers );
+               ref_get ( timer->refcnt );
+       }
        timer->start = currticks();
        timer->running = 1;
 
@@ -136,6 +138,8 @@ void stop_timer ( struct retry_timer *timer ) {
                              timer, timer->timeout );
                }
        }
+
+       ref_put ( timer->refcnt );
 }
 
 /**
@@ -164,7 +168,9 @@ static void timer_expired ( struct retry_timer *timer ) {
              timer, timer->timeout );
 
        /* Call expiry callback */
-       timer->expired ( timer, fail ); 
+       timer->expired ( timer, fail );
+
+       ref_put ( timer->refcnt );
 }
 
 /**

diff --git a/src/net/tcp.c b/src/net/tcp.c
index b2d882732268a9bfbf934905d1bce47a7bf44896..1c824bdff96f8f0f6095e1f34b559fe701035fcf 100644 (file)
--- a/src/net/tcp.c
+++ b/src/net/tcp.c
@@ -265,8 +265,8 @@ static int tcp_open ( struct interface *xfer, struct sockaddr *peer,
        DBGC ( tcp, "TCP %p allocated\n", tcp );
        ref_init ( &tcp->refcnt, NULL );
        intf_init ( &tcp->xfer, &tcp_xfer_desc, &tcp->refcnt );
-       timer_init ( &tcp->timer, tcp_expired );
-       timer_init ( &tcp->wait, tcp_wait_expired );
+       timer_init ( &tcp->timer, tcp_expired, &tcp->refcnt );
+       timer_init ( &tcp->wait, tcp_wait_expired, &tcp->refcnt );
        tcp->prev_tcp_state = TCP_CLOSED;
        tcp->tcp_state = TCP_STATE_SENT ( TCP_SYN );
        tcp_dump_state ( tcp );

diff --git a/src/net/udp/dhcp.c b/src/net/udp/dhcp.c
index 77d4654537faf47b6035229e9cad32dd31880b8d..1169abaae986580370d36e48d57b6d92c7f2195a 100644 (file)
--- a/src/net/udp/dhcp.c
+++ b/src/net/udp/dhcp.c
@@ -1425,7 +1425,7 @@ int start_dhcp ( struct interface *job, struct net_device *netdev ) {
        ref_init ( &dhcp->refcnt, dhcp_free );
        intf_init ( &dhcp->job, &dhcp_job_desc, &dhcp->refcnt );
        intf_init ( &dhcp->xfer, &dhcp_xfer_desc, &dhcp->refcnt );
-       timer_init ( &dhcp->timer, dhcp_timer_expired );
+       timer_init ( &dhcp->timer, dhcp_timer_expired, &dhcp->refcnt );
        dhcp->netdev = netdev_get ( netdev );
        dhcp->local.sin_family = AF_INET;
        dhcp->local.sin_port = htons ( BOOTPC_PORT );
@@ -1528,7 +1528,7 @@ int start_pxebs ( struct interface *job, struct net_device *netdev,
        ref_init ( &dhcp->refcnt, dhcp_free );
        intf_init ( &dhcp->job, &dhcp_job_desc, &dhcp->refcnt );
        intf_init ( &dhcp->xfer, &dhcp_xfer_desc, &dhcp->refcnt );
-       timer_init ( &dhcp->timer, dhcp_timer_expired );
+       timer_init ( &dhcp->timer, dhcp_timer_expired, &dhcp->refcnt );
        dhcp->netdev = netdev_get ( netdev );
        dhcp->local.sin_family = AF_INET;
        fetch_ipv4_setting ( netdev_settings ( netdev ), &ip_setting,

diff --git a/src/net/udp/dns.c b/src/net/udp/dns.c
index 8283e6fbac47bce37097e4bd9c7d0bc878221af1..ddbccc32297cfaf24d04b9c9d56351d85548df2a 100644 (file)
--- a/src/net/udp/dns.c
+++ b/src/net/udp/dns.c
@@ -527,7 +527,7 @@ static int dns_resolv ( struct interface *resolv,
        ref_init ( &dns->refcnt, NULL );
        intf_init ( &dns->resolv, &dns_resolv_desc, &dns->refcnt );
        intf_init ( &dns->socket, &dns_socket_desc, &dns->refcnt );
-       timer_init ( &dns->timer, dns_timer_expired );
+       timer_init ( &dns->timer, dns_timer_expired, &dns->refcnt );
        memcpy ( &dns->sa, sa, sizeof ( dns->sa ) );
 
        /* Create query */

diff --git a/src/net/udp/slam.c b/src/net/udp/slam.c
index 026bc1797cbfae6fd233ba1ee01a3169c4a90914..0de138cdfba538de9cb90fbc6f9771972fb4e593 100644 (file)
--- a/src/net/udp/slam.c
+++ b/src/net/udp/slam.c
@@ -695,8 +695,10 @@ static int slam_open ( struct interface *xfer, struct uri *uri ) {
        intf_init ( &slam->xfer, &slam_xfer_desc, &slam->refcnt );
        intf_init ( &slam->socket, &slam_socket_desc, &slam->refcnt );
        intf_init ( &slam->mc_socket, &slam_mc_socket_desc, &slam->refcnt );
-       timer_init ( &slam->master_timer, slam_master_timer_expired );
-       timer_init ( &slam->slave_timer, slam_slave_timer_expired );
+       timer_init ( &slam->master_timer, slam_master_timer_expired,
+                    &slam->refcnt );
+       timer_init ( &slam->slave_timer, slam_slave_timer_expired,
+                    &slam->refcnt );
        /* Fake an invalid cached header of { 0x00, ... } */
        slam->header_len = 1;
        /* Fake parameters for initial NACK */

diff --git a/src/net/udp/tftp.c b/src/net/udp/tftp.c
index e8223c99cd57f6b1083d9d1e5a1f70f639780170..777632ef9379a676f07167120ec4f4dbdb085838 100644 (file)
--- a/src/net/udp/tftp.c
+++ b/src/net/udp/tftp.c
@@ -1097,7 +1097,7 @@ static int tftp_core_open ( struct interface *xfer, struct uri *uri,
        intf_init ( &tftp->xfer, &tftp_xfer_desc, &tftp->refcnt );
        intf_init ( &tftp->socket, &tftp_socket_desc, &tftp->refcnt );
        intf_init ( &tftp->mc_socket, &tftp_mc_socket_desc, &tftp->refcnt );
-       timer_init ( &tftp->timer, tftp_timer_expired );
+       timer_init ( &tftp->timer, tftp_timer_expired, &tftp->refcnt );
        tftp->uri = uri_get ( uri );
        tftp->blksize = TFTP_DEFAULT_BLKSIZE;
        tftp->flags = flags;