diff options
Diffstat (limited to 'drivers/net/xen-netback')
-rw-r--r-- | drivers/net/xen-netback/common.h | 2 | ||||
-rw-r--r-- | drivers/net/xen-netback/interface.c | 23 | ||||
-rw-r--r-- | drivers/net/xen-netback/netback.c | 108 | ||||
-rw-r--r-- | drivers/net/xen-netback/xenbus.c | 156 |
4 files changed, 216 insertions, 73 deletions
diff --git a/drivers/net/xen-netback/common.h b/drivers/net/xen-netback/common.h index 9d7f1723dd8f..f2faa779e3fe 100644 --- a/drivers/net/xen-netback/common.h +++ b/drivers/net/xen-netback/common.h @@ -88,6 +88,7 @@ struct xenvif { unsigned long credit_usec; unsigned long remaining_credit; struct timer_list credit_timeout; + u64 credit_window_start; /* Statistics */ unsigned long rx_gso_checksum_fixup; @@ -115,6 +116,7 @@ struct xenvif *xenvif_alloc(struct device *parent, int xenvif_connect(struct xenvif *vif, unsigned long tx_ring_ref, unsigned long rx_ring_ref, unsigned int evtchn); void xenvif_disconnect(struct xenvif *vif); +void xenvif_free(struct xenvif *vif); void xenvif_get(struct xenvif *vif); void xenvif_put(struct xenvif *vif); diff --git a/drivers/net/xen-netback/interface.c b/drivers/net/xen-netback/interface.c index d98414168485..540a796593a3 100644 --- a/drivers/net/xen-netback/interface.c +++ b/drivers/net/xen-netback/interface.c @@ -275,8 +275,7 @@ struct xenvif *xenvif_alloc(struct device *parent, domid_t domid, vif->credit_bytes = vif->remaining_credit = ~0UL; vif->credit_usec = 0UL; init_timer(&vif->credit_timeout); - /* Initialize 'expires' now: it's used to track the credit window. */ - vif->credit_timeout.expires = jiffies; + vif->credit_window_start = get_jiffies_64(); dev->netdev_ops = &xenvif_netdev_ops; dev->hw_features = NETIF_F_SG | NETIF_F_IP_CSUM | NETIF_F_TSO; @@ -304,6 +303,9 @@ struct xenvif *xenvif_alloc(struct device *parent, domid_t domid, } netdev_dbg(dev, "Successfully created xenvif\n"); + + __module_get(THIS_MODULE); + return vif; } @@ -363,15 +365,22 @@ void xenvif_disconnect(struct xenvif *vif) if (netif_carrier_ok(vif->dev)) xenvif_carrier_off(vif); + if (vif->irq) { + unbind_from_irqhandler(vif->irq, vif); + vif->irq = 0; + } + + xen_netbk_unmap_frontend_rings(vif); +} + +void xenvif_free(struct xenvif *vif) +{ atomic_dec(&vif->refcnt); wait_event(vif->waiting_to_free, atomic_read(&vif->refcnt) == 0); - if (vif->irq) - unbind_from_irqhandler(vif->irq, vif); - unregister_netdev(vif->dev); - xen_netbk_unmap_frontend_rings(vif); - free_netdev(vif->dev); + + module_put(THIS_MODULE); } diff --git a/drivers/net/xen-netback/netback.c b/drivers/net/xen-netback/netback.c index 8c20935d72c9..70b830f6c4bf 100644 --- a/drivers/net/xen-netback/netback.c +++ b/drivers/net/xen-netback/netback.c @@ -347,13 +347,56 @@ static bool start_new_rx_buffer(int offset, unsigned long size, int head) * into multiple copies tend to give large frags their * own buffers as before. */ - if ((offset + size > MAX_BUFFER_OFFSET) && - (size <= MAX_BUFFER_OFFSET) && offset && !head) + BUG_ON(size > MAX_BUFFER_OFFSET); + if ((offset + size > MAX_BUFFER_OFFSET) && offset && !head) return true; return false; } +struct xenvif_count_slot_state { + unsigned long copy_off; + bool head; +}; + +unsigned int xenvif_count_frag_slots(struct xenvif *vif, + unsigned long offset, unsigned long size, + struct xenvif_count_slot_state *state) +{ + unsigned count = 0; + + offset &= ~PAGE_MASK; + + while (size > 0) { + unsigned long bytes; + + bytes = PAGE_SIZE - offset; + + if (bytes > size) + bytes = size; + + if (start_new_rx_buffer(state->copy_off, bytes, state->head)) { + count++; + state->copy_off = 0; + } + + if (state->copy_off + bytes > MAX_BUFFER_OFFSET) + bytes = MAX_BUFFER_OFFSET - state->copy_off; + + state->copy_off += bytes; + + offset += bytes; + size -= bytes; + + if (offset == PAGE_SIZE) + offset = 0; + + state->head = false; + } + + return count; +} + /* * Figure out how many ring slots we're going to need to send @skb to * the guest. This function is essentially a dry run of @@ -361,48 +404,39 @@ static bool start_new_rx_buffer(int offset, unsigned long size, int head) */ unsigned int xen_netbk_count_skb_slots(struct xenvif *vif, struct sk_buff *skb) { + struct xenvif_count_slot_state state; unsigned int count; - int i, copy_off; + unsigned char *data; + unsigned i; - count = DIV_ROUND_UP(skb_headlen(skb), PAGE_SIZE); + state.head = true; + state.copy_off = 0; - copy_off = skb_headlen(skb) % PAGE_SIZE; + /* Slot for the first (partial) page of data. */ + count = 1; + /* Need a slot for the GSO prefix for GSO extra data? */ if (skb_shinfo(skb)->gso_size) count++; - for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { - unsigned long size = skb_frag_size(&skb_shinfo(skb)->frags[i]); - unsigned long offset = skb_shinfo(skb)->frags[i].page_offset; - unsigned long bytes; - - offset &= ~PAGE_MASK; - - while (size > 0) { - BUG_ON(offset >= PAGE_SIZE); - BUG_ON(copy_off > MAX_BUFFER_OFFSET); - - bytes = PAGE_SIZE - offset; - - if (bytes > size) - bytes = size; + data = skb->data; + while (data < skb_tail_pointer(skb)) { + unsigned long offset = offset_in_page(data); + unsigned long size = PAGE_SIZE - offset; - if (start_new_rx_buffer(copy_off, bytes, 0)) { - count++; - copy_off = 0; - } + if (data + size > skb_tail_pointer(skb)) + size = skb_tail_pointer(skb) - data; - if (copy_off + bytes > MAX_BUFFER_OFFSET) - bytes = MAX_BUFFER_OFFSET - copy_off; + count += xenvif_count_frag_slots(vif, offset, size, &state); - copy_off += bytes; + data += size; + } - offset += bytes; - size -= bytes; + for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { + unsigned long size = skb_frag_size(&skb_shinfo(skb)->frags[i]); + unsigned long offset = skb_shinfo(skb)->frags[i].page_offset; - if (offset == PAGE_SIZE) - offset = 0; - } + count += xenvif_count_frag_slots(vif, offset, size, &state); } return count; } @@ -1389,9 +1423,8 @@ out: static bool tx_credit_exceeded(struct xenvif *vif, unsigned size) { - unsigned long now = jiffies; - unsigned long next_credit = - vif->credit_timeout.expires + + u64 now = get_jiffies_64(); + u64 next_credit = vif->credit_window_start + msecs_to_jiffies(vif->credit_usec / 1000); /* Timer could already be pending in rare cases. */ @@ -1399,8 +1432,8 @@ static bool tx_credit_exceeded(struct xenvif *vif, unsigned size) return true; /* Passed the point where we can replenish credit? */ - if (time_after_eq(now, next_credit)) { - vif->credit_timeout.expires = now; + if (time_after_eq64(now, next_credit)) { + vif->credit_window_start = now; tx_add_credit(vif); } @@ -1412,6 +1445,7 @@ static bool tx_credit_exceeded(struct xenvif *vif, unsigned size) tx_credit_callback; mod_timer(&vif->credit_timeout, next_credit); + vif->credit_window_start = next_credit; return true; } diff --git a/drivers/net/xen-netback/xenbus.c b/drivers/net/xen-netback/xenbus.c index 410018c4c528..8a9e8750703f 100644 --- a/drivers/net/xen-netback/xenbus.c +++ b/drivers/net/xen-netback/xenbus.c @@ -24,6 +24,12 @@ struct backend_info { struct xenbus_device *dev; struct xenvif *vif; + + /* This is the state that will be reflected in xenstore when any + * active hotplug script completes. + */ + enum xenbus_state state; + enum xenbus_state frontend_state; struct xenbus_watch hotplug_status_watch; u8 have_hotplug_status_watch:1; @@ -33,16 +39,20 @@ static int connect_rings(struct backend_info *); static void connect(struct backend_info *); static void backend_create_xenvif(struct backend_info *be); static void unregister_hotplug_status_watch(struct backend_info *be); +static void set_backend_state(struct backend_info *be, + enum xenbus_state state); static int netback_remove(struct xenbus_device *dev) { struct backend_info *be = dev_get_drvdata(&dev->dev); + set_backend_state(be, XenbusStateClosed); + unregister_hotplug_status_watch(be); if (be->vif) { kobject_uevent(&dev->dev.kobj, KOBJ_OFFLINE); xenbus_rm(XBT_NIL, dev->nodename, "hotplug-status"); - xenvif_disconnect(be->vif); + xenvif_free(be->vif); be->vif = NULL; } kfree(be); @@ -126,6 +136,8 @@ static int netback_probe(struct xenbus_device *dev, if (err) goto fail; + be->state = XenbusStateInitWait; + /* This kicks hotplug scripts, so do it immediately. */ backend_create_xenvif(be); @@ -198,15 +210,113 @@ static void backend_create_xenvif(struct backend_info *be) kobject_uevent(&dev->dev.kobj, KOBJ_ONLINE); } +static void backend_disconnect(struct backend_info *be) +{ + if (be->vif) + xenvif_disconnect(be->vif); +} -static void disconnect_backend(struct xenbus_device *dev) +static void backend_connect(struct backend_info *be) { - struct backend_info *be = dev_get_drvdata(&dev->dev); + if (be->vif) + connect(be); +} - if (be->vif) { - xenbus_rm(XBT_NIL, dev->nodename, "hotplug-status"); - xenvif_disconnect(be->vif); - be->vif = NULL; +static inline void backend_switch_state(struct backend_info *be, + enum xenbus_state state) +{ + struct xenbus_device *dev = be->dev; + + pr_debug("%s -> %s\n", dev->nodename, xenbus_strstate(state)); + be->state = state; + + /* If we are waiting for a hotplug script then defer the + * actual xenbus state change. + */ + if (!be->have_hotplug_status_watch) + xenbus_switch_state(dev, state); +} + +/* Handle backend state transitions: + * + * The backend state starts in InitWait and the following transitions are + * allowed. + * + * InitWait -> Connected + * + * ^ \ | + * | \ | + * | \ | + * | \ | + * | \ | + * | \ | + * | V V + * + * Closed <-> Closing + * + * The state argument specifies the eventual state of the backend and the + * function transitions to that state via the shortest path. + */ +static void set_backend_state(struct backend_info *be, + enum xenbus_state state) +{ + while (be->state != state) { + switch (be->state) { + case XenbusStateClosed: + switch (state) { + case XenbusStateInitWait: + case XenbusStateConnected: + pr_info("%s: prepare for reconnect\n", + be->dev->nodename); + backend_switch_state(be, XenbusStateInitWait); + break; + case XenbusStateClosing: + backend_switch_state(be, XenbusStateClosing); + break; + default: + BUG(); + } + break; + case XenbusStateInitWait: + switch (state) { + case XenbusStateConnected: + backend_connect(be); + backend_switch_state(be, XenbusStateConnected); + break; + case XenbusStateClosing: + case XenbusStateClosed: + backend_switch_state(be, XenbusStateClosing); + break; + default: + BUG(); + } + break; + case XenbusStateConnected: + switch (state) { + case XenbusStateInitWait: + case XenbusStateClosing: + case XenbusStateClosed: + backend_disconnect(be); + backend_switch_state(be, XenbusStateClosing); + break; + default: + BUG(); + } + break; + case XenbusStateClosing: + switch (state) { + case XenbusStateInitWait: + case XenbusStateConnected: + case XenbusStateClosed: + backend_switch_state(be, XenbusStateClosed); + break; + default: + BUG(); + } + break; + default: + BUG(); + } } } @@ -218,43 +328,33 @@ static void frontend_changed(struct xenbus_device *dev, { struct backend_info *be = dev_get_drvdata(&dev->dev); - pr_debug("frontend state %s", xenbus_strstate(frontend_state)); + pr_debug("%s -> %s\n", dev->otherend, xenbus_strstate(frontend_state)); be->frontend_state = frontend_state; switch (frontend_state) { case XenbusStateInitialising: - if (dev->state == XenbusStateClosed) { - printk(KERN_INFO "%s: %s: prepare for reconnect\n", - __func__, dev->nodename); - xenbus_switch_state(dev, XenbusStateInitWait); - } + set_backend_state(be, XenbusStateInitWait); break; case XenbusStateInitialised: break; case XenbusStateConnected: - if (dev->state == XenbusStateConnected) - break; - backend_create_xenvif(be); - if (be->vif) - connect(be); + set_backend_state(be, XenbusStateConnected); break; case XenbusStateClosing: - if (be->vif) - kobject_uevent(&dev->dev.kobj, KOBJ_OFFLINE); - disconnect_backend(dev); - xenbus_switch_state(dev, XenbusStateClosing); + set_backend_state(be, XenbusStateClosing); break; case XenbusStateClosed: - xenbus_switch_state(dev, XenbusStateClosed); + set_backend_state(be, XenbusStateClosed); if (xenbus_dev_is_online(dev)) break; /* fall through if not online */ case XenbusStateUnknown: + set_backend_state(be, XenbusStateClosed); device_unregister(&dev->dev); break; @@ -347,7 +447,9 @@ static void hotplug_status_changed(struct xenbus_watch *watch, if (IS_ERR(str)) return; if (len == sizeof("connected")-1 && !memcmp(str, "connected", len)) { - xenbus_switch_state(be->dev, XenbusStateConnected); + /* Complete any pending state change */ + xenbus_switch_state(be->dev, be->state); + /* Not interested in this watch anymore. */ unregister_hotplug_status_watch(be); } @@ -377,12 +479,8 @@ static void connect(struct backend_info *be) err = xenbus_watch_pathfmt(dev, &be->hotplug_status_watch, hotplug_status_changed, "%s/%s", dev->nodename, "hotplug-status"); - if (err) { - /* Switch now, since we can't do a watch. */ - xenbus_switch_state(dev, XenbusStateConnected); - } else { + if (!err) be->have_hotplug_status_watch = 1; - } netif_wake_queue(be->vif->dev); } |