diff options
Diffstat (limited to 'drivers/xen/pvcalls-back.c')
-rw-r--r-- | drivers/xen/pvcalls-back.c | 87 |
1 files changed, 52 insertions, 35 deletions
diff --git a/drivers/xen/pvcalls-back.c b/drivers/xen/pvcalls-back.c index c57c71b7d53d..d6f945fd4147 100644 --- a/drivers/xen/pvcalls-back.c +++ b/drivers/xen/pvcalls-back.c @@ -24,7 +24,7 @@ #define PVCALLS_VERSIONS "1" #define MAX_RING_ORDER XENBUS_MAX_RING_GRANT_ORDER -struct pvcalls_back_global { +static struct pvcalls_back_global { struct list_head frontends; struct semaphore frontends_lock; } pvcalls_back_global; @@ -66,6 +66,7 @@ struct sock_mapping { atomic_t write; atomic_t io; atomic_t release; + atomic_t eoi; void (*saved_data_ready)(struct sock *sk); struct pvcalls_ioworker ioworker; }; @@ -87,7 +88,7 @@ static int pvcalls_back_release_active(struct xenbus_device *dev, struct pvcalls_fedata *fedata, struct sock_mapping *map); -static void pvcalls_conn_back_read(void *opaque) +static bool pvcalls_conn_back_read(void *opaque) { struct sock_mapping *map = (struct sock_mapping *)opaque; struct msghdr msg; @@ -107,17 +108,17 @@ static void pvcalls_conn_back_read(void *opaque) virt_mb(); if (error) - return; + return false; size = pvcalls_queued(prod, cons, array_size); if (size >= array_size) - return; + return false; spin_lock_irqsave(&map->sock->sk->sk_receive_queue.lock, flags); if (skb_queue_empty(&map->sock->sk->sk_receive_queue)) { atomic_set(&map->read, 0); spin_unlock_irqrestore(&map->sock->sk->sk_receive_queue.lock, flags); - return; + return true; } spin_unlock_irqrestore(&map->sock->sk->sk_receive_queue.lock, flags); wanted = array_size - size; @@ -141,7 +142,7 @@ static void pvcalls_conn_back_read(void *opaque) ret = inet_recvmsg(map->sock, &msg, wanted, MSG_DONTWAIT); WARN_ON(ret > wanted); if (ret == -EAGAIN) /* shouldn't happen */ - return; + return true; if (!ret) ret = -ENOTCONN; spin_lock_irqsave(&map->sock->sk->sk_receive_queue.lock, flags); @@ -160,10 +161,10 @@ static void pvcalls_conn_back_read(void *opaque) virt_wmb(); notify_remote_via_irq(map->irq); - return; + return true; } -static void pvcalls_conn_back_write(struct sock_mapping *map) +static bool pvcalls_conn_back_write(struct sock_mapping *map) { struct pvcalls_data_intf *intf = map->ring; struct pvcalls_data *data = &map->data; @@ -180,7 +181,7 @@ static void pvcalls_conn_back_write(struct sock_mapping *map) array_size = XEN_FLEX_RING_SIZE(map->ring_order); size = pvcalls_queued(prod, cons, array_size); if (size == 0) - return; + return false; memset(&msg, 0, sizeof(msg)); msg.msg_flags |= MSG_DONTWAIT; @@ -198,12 +199,11 @@ static void pvcalls_conn_back_write(struct sock_mapping *map) atomic_set(&map->write, 0); ret = inet_sendmsg(map->sock, &msg, size); - if (ret == -EAGAIN || (ret >= 0 && ret < size)) { + if (ret == -EAGAIN) { atomic_inc(&map->write); atomic_inc(&map->io); + return true; } - if (ret == -EAGAIN) - return; /* write the data, then update the indexes */ virt_wmb(); @@ -216,9 +216,13 @@ static void pvcalls_conn_back_write(struct sock_mapping *map) } /* update the indexes, then notify the other end */ virt_wmb(); - if (prod != cons + ret) + if (prod != cons + ret) { atomic_inc(&map->write); + atomic_inc(&map->io); + } notify_remote_via_irq(map->irq); + + return true; } static void pvcalls_back_ioworker(struct work_struct *work) @@ -227,6 +231,7 @@ static void pvcalls_back_ioworker(struct work_struct *work) struct pvcalls_ioworker, register_work); struct sock_mapping *map = container_of(ioworker, struct sock_mapping, ioworker); + unsigned int eoi_flags = XEN_EOI_FLAG_SPURIOUS; while (atomic_read(&map->io) > 0) { if (atomic_read(&map->release) > 0) { @@ -234,10 +239,18 @@ static void pvcalls_back_ioworker(struct work_struct *work) return; } - if (atomic_read(&map->read) > 0) - pvcalls_conn_back_read(map); - if (atomic_read(&map->write) > 0) - pvcalls_conn_back_write(map); + if (atomic_read(&map->read) > 0 && + pvcalls_conn_back_read(map)) + eoi_flags = 0; + if (atomic_read(&map->write) > 0 && + pvcalls_conn_back_write(map)) + eoi_flags = 0; + + if (atomic_read(&map->eoi) > 0 && !atomic_read(&map->write)) { + atomic_set(&map->eoi, 0); + xen_irq_lateeoi(map->irq, eoi_flags); + eoi_flags = XEN_EOI_FLAG_SPURIOUS; + } atomic_dec(&map->io); } @@ -300,7 +313,7 @@ static struct sock_mapping *pvcalls_new_active_socket( struct pvcalls_fedata *fedata, uint64_t id, grant_ref_t ref, - uint32_t evtchn, + evtchn_port_t evtchn, struct socket *sock) { int ret; @@ -334,12 +347,9 @@ static struct sock_mapping *pvcalls_new_active_socket( goto out; map->bytes = page; - ret = bind_interdomain_evtchn_to_irqhandler(fedata->dev->otherend_id, - evtchn, - pvcalls_back_conn_event, - 0, - "pvcalls-backend", - map); + ret = bind_interdomain_evtchn_to_irqhandler_lateeoi( + fedata->dev, evtchn, + pvcalls_back_conn_event, 0, "pvcalls-backend", map); if (ret < 0) goto out; map->irq = ret; @@ -455,7 +465,6 @@ static int pvcalls_back_release_passive(struct xenbus_device *dev, write_unlock_bh(&mappass->sock->sk->sk_callback_lock); } sock_release(mappass->sock); - flush_workqueue(mappass->wq); destroy_workqueue(mappass->wq); kfree(mappass); @@ -873,15 +882,18 @@ static irqreturn_t pvcalls_back_event(int irq, void *dev_id) { struct xenbus_device *dev = dev_id; struct pvcalls_fedata *fedata = NULL; + unsigned int eoi_flags = XEN_EOI_FLAG_SPURIOUS; - if (dev == NULL) - return IRQ_HANDLED; + if (dev) { + fedata = dev_get_drvdata(&dev->dev); + if (fedata) { + pvcalls_back_work(fedata); + eoi_flags = 0; + } + } - fedata = dev_get_drvdata(&dev->dev); - if (fedata == NULL) - return IRQ_HANDLED; + xen_irq_lateeoi(irq, eoi_flags); - pvcalls_back_work(fedata); return IRQ_HANDLED; } @@ -891,12 +903,15 @@ static irqreturn_t pvcalls_back_conn_event(int irq, void *sock_map) struct pvcalls_ioworker *iow; if (map == NULL || map->sock == NULL || map->sock->sk == NULL || - map->sock->sk->sk_user_data != map) + map->sock->sk->sk_user_data != map) { + xen_irq_lateeoi(irq, 0); return IRQ_HANDLED; + } iow = &map->ioworker; atomic_inc(&map->write); + atomic_inc(&map->eoi); atomic_inc(&map->io); queue_work(iow->wq, &iow->register_work); @@ -905,7 +920,8 @@ static irqreturn_t pvcalls_back_conn_event(int irq, void *sock_map) static int backend_connect(struct xenbus_device *dev) { - int err, evtchn; + int err; + evtchn_port_t evtchn; grant_ref_t ring_ref; struct pvcalls_fedata *fedata = NULL; @@ -931,7 +947,7 @@ static int backend_connect(struct xenbus_device *dev) goto error; } - err = bind_interdomain_evtchn_to_irq(dev->otherend_id, evtchn); + err = bind_interdomain_evtchn_to_irq_lateeoi(dev, evtchn); if (err < 0) goto error; fedata->irq = err; @@ -1087,7 +1103,8 @@ static void set_backend_state(struct xenbus_device *dev, case XenbusStateInitialised: switch (state) { case XenbusStateConnected: - backend_connect(dev); + if (backend_connect(dev)) + return; xenbus_switch_state(dev, XenbusStateConnected); break; case XenbusStateClosing: |