From 2aa824e5ceb5310e5f1e69011d9c20a8704078ce Mon Sep 17 00:00:00 2001 From: Jean Tourrilhes Date: Thu, 8 Jan 2004 10:09:23 -0800 Subject: [PATCH] [IRDA]: Fix a potential dealock in sir-dev state machine. Also, make sir-dev locking compatible with irport. From Martin Diehl. --- drivers/net/irda/sir_dev.c | 23 +++++++++++++---------- drivers/net/irda/sir_kthread.c | 9 ++++----- 2 files changed, 17 insertions(+), 15 deletions(-) diff --git a/drivers/net/irda/sir_dev.c b/drivers/net/irda/sir_dev.c index a5c472575c3c9..2c4a88894f187 100644 --- a/drivers/net/irda/sir_dev.c +++ b/drivers/net/irda/sir_dev.c @@ -62,24 +62,25 @@ int sirdev_set_dongle(struct sir_dev *dev, IRDA_DONGLE type) int sirdev_raw_write(struct sir_dev *dev, const char *buf, int len) { + unsigned long flags; int ret; if (unlikely(len > dev->tx_buff.truesize)) return -ENOSPC; - spin_lock_bh(&dev->tx_lock); /* serialize with other tx operations */ - while (dev->tx_buff.len > 0) { /* wait until tx idle */ - spin_unlock_bh(&dev->tx_lock); + spin_lock_irqsave(&dev->tx_lock, flags); /* serialize with other tx operations */ + while (dev->tx_buff.len > 0) { /* wait until tx idle */ + spin_unlock_irqrestore(&dev->tx_lock, flags); set_current_state(TASK_UNINTERRUPTIBLE); schedule_timeout(MSECS_TO_JIFFIES(10)); - spin_lock_bh(&dev->tx_lock); + spin_lock_irqsave(&dev->tx_lock, flags); } dev->tx_buff.data = dev->tx_buff.head; memcpy(dev->tx_buff.data, buf, len); ret = dev->drv->do_write(dev, dev->tx_buff.data, dev->tx_buff.len); - spin_unlock_bh(&dev->tx_lock); + spin_unlock_irqrestore(&dev->tx_lock, flags); return ret; } @@ -114,11 +115,12 @@ int sirdev_raw_read(struct sir_dev *dev, char *buf, int len) void sirdev_write_complete(struct sir_dev *dev) { + unsigned long flags; struct sk_buff *skb; int actual = 0; int err; - spin_lock_bh(&dev->tx_lock); + spin_lock_irqsave(&dev->tx_lock, flags); IRDA_DEBUG(3, "%s() - dev->tx_buff.len = %d\n", __FUNCTION__, dev->tx_buff.len); @@ -143,7 +145,7 @@ void sirdev_write_complete(struct sir_dev *dev) dev->tx_buff.len = 0; } if (dev->tx_buff.len > 0) { - spin_unlock_bh(&dev->tx_lock); + spin_unlock_irqrestore(&dev->tx_lock, flags); return; } } @@ -190,7 +192,7 @@ void sirdev_write_complete(struct sir_dev *dev) netif_wake_queue(dev->netdev); } - spin_unlock_bh(&dev->tx_lock); + spin_unlock_irqrestore(&dev->tx_lock, flags); } /* called from client driver - likely with bh-context - to give us @@ -258,6 +260,7 @@ static struct net_device_stats *sirdev_get_stats(struct net_device *ndev) static int sirdev_hard_xmit(struct sk_buff *skb, struct net_device *ndev) { struct sir_dev *dev = ndev->priv; + unsigned long flags; int actual = 0; int err; s32 speed; @@ -307,7 +310,7 @@ static int sirdev_hard_xmit(struct sk_buff *skb, struct net_device *ndev) } /* serialize with write completion */ - spin_lock_bh(&dev->tx_lock); + spin_lock_irqsave(&dev->tx_lock, flags); /* Copy skb to tx_buff while wrapping, stuffing and making CRC */ dev->tx_buff.len = async_wrap_skb(skb, dev->tx_buff.data, dev->tx_buff.truesize); @@ -337,7 +340,7 @@ static int sirdev_hard_xmit(struct sk_buff *skb, struct net_device *ndev) dev->stats.tx_dropped++; netif_wake_queue(ndev); } - spin_unlock_bh(&dev->tx_lock); + spin_unlock_irqrestore(&dev->tx_lock, flags); return 0; } diff --git a/drivers/net/irda/sir_kthread.c b/drivers/net/irda/sir_kthread.c index 620b524bd80ea..51148178ac707 100644 --- a/drivers/net/irda/sir_kthread.c +++ b/drivers/net/irda/sir_kthread.c @@ -436,14 +436,13 @@ int sirdev_schedule_request(struct sir_dev *dev, int initial_state, unsigned par IRDA_DEBUG(2, "%s - state=0x%04x / param=%u\n", __FUNCTION__, initial_state, param); - if (in_interrupt()) { - if (down_trylock(&fsm->sem)) { + if (down_trylock(&fsm->sem)) { + if (in_interrupt() || in_atomic() || irqs_disabled()) { IRDA_DEBUG(1, "%s(), state machine busy!\n", __FUNCTION__); return -EWOULDBLOCK; - } + } else + down(&fsm->sem); } - else - down(&fsm->sem); if (fsm->state == SIRDEV_STATE_DEAD) { /* race with sirdev_close should never happen */ -- 2.53.0