[PATCH 2.5] : ir252_drivers_locking_fixes-3.diff

From: Jean Tourrilhes (jt@bougret.hpl.hp.com)
Date: Thu Aug 29 2002 - 17:50:50 EST


ir252_drivers_locking_fixes-3.diff :
----------------------------------
        o [CORRECT] Remove all "save_flags(flags);cli();" in IrDA driver
        o [FEATURE] Rework broken locking in irport
        o [FEATURE] Finish locking cleanup in nsc-ircc
        o [FEATURE] Improve locking in smc-ircc & w83977af_ir

diff -u -p -r linux/include/net/irda-d6/irtty.h linux/include/net/irda/irtty.h
--- linux/include/net/irda-d6/irtty.h Sat Jun 8 22:31:17 2002
+++ linux/include/net/irda/irtty.h Fri Aug 23 13:40:59 2002
@@ -62,6 +62,9 @@ struct irtty_cb {
         struct qos_info qos; /* QoS capabilities for this device */
         dongle_t *dongle; /* Dongle driver */
 
+
+ spinlock_t lock; /* For serializing operations */
+
         __u32 new_speed;
          __u32 flags; /* Interface flags */
 
diff -u -p -r linux/include/net/irda-d6/smc-ircc.h linux/include/net/irda/smc-ircc.h
--- linux/include/net/irda-d6/smc-ircc.h Sat Jun 8 22:27:46 2002
+++ linux/include/net/irda/smc-ircc.h Fri Aug 23 15:21:45 2002
@@ -165,7 +165,9 @@ struct ircc_cb {
 
         struct irport_cb *irport;
 
- spinlock_t lock; /* For serializing operations */
+ /* Locking : half of our operations are done with irport, so we
+ * use the irport spinlock to make sure *everything* is properly
+ * synchronised - Jean II */
         
         __u32 new_speed;
         __u32 flags; /* Interface flags */
diff -u -p -r linux/include/net/irda-d6/w83977af_ir.h linux/include/net/irda/w83977af_ir.h
--- linux/include/net/irda-d6/w83977af_ir.h Sat Jun 8 22:26:53 2002
+++ linux/include/net/irda/w83977af_ir.h Fri Aug 23 11:56:39 2002
@@ -179,6 +179,11 @@ struct w83977af_ir {
         chipio_t io; /* IrDA controller information */
         iobuff_t tx_buff; /* Transmit buffer */
         iobuff_t rx_buff; /* Receive buffer */
+
+ /* Note : currently locking is *very* incomplete, but this
+ * will get you started. Check in nsc-ircc.c for a proper
+ * locking strategy. - Jean II */
+ spinlock_t lock; /* For serializing operations */
         
         __u32 flags; /* Interface flags */
         __u32 new_speed;
diff -u -p -r linux/drivers/net/irda-d6/irda-usb.c linux/drivers/net/irda/irda-usb.c
--- linux/drivers/net/irda-d6/irda-usb.c Mon Aug 19 14:43:27 2002
+++ linux/drivers/net/irda/irda-usb.c Wed Aug 21 16:27:54 2002
@@ -1171,7 +1171,7 @@ static inline int irda_usb_open(struct i
         irda_usb_init_qos(self);
         
         /* Initialise list of skb beeing curently transmitted */
- self->tx_list = hashbin_new(HB_GLOBAL);
+ self->tx_list = hashbin_new(HB_NOLOCK); /* unused */
 
         /* Allocate the buffer for speed changes */
         /* Don't change this buffer size and allocation without doing
diff -u -p -r linux/drivers/net/irda-d6/irport.c linux/drivers/net/irda/irport.c
--- linux/drivers/net/irda-d6/irport.c Mon Aug 19 14:41:00 2002
+++ linux/drivers/net/irda/irport.c Thu Aug 29 10:20:47 2002
@@ -140,7 +140,7 @@ irport_open(int i, unsigned int iobase,
         void *ret;
         int err;
 
- IRDA_DEBUG(0, __FUNCTION__ "()\n");
+ IRDA_DEBUG(1, __FUNCTION__ "()\n");
 
         /*
          * Allocate new instance of the driver
@@ -284,14 +284,13 @@ int irport_close(struct irport_cb *self)
 
 void irport_start(struct irport_cb *self)
 {
- unsigned long flags;
         int iobase;
 
         iobase = self->io.sir_base;
 
         irport_stop(self);
         
- spin_lock_irqsave(&self->lock, flags);
+ /* We can't lock, we may be called from a FIR driver - Jean II */
 
         /* Initialize UART */
         outb(UART_LCR_WLEN8, iobase+UART_LCR); /* Reset DLAB */
@@ -299,26 +298,21 @@ void irport_start(struct irport_cb *self
         
         /* Turn on interrups */
         outb(UART_IER_RLSI | UART_IER_RDI |UART_IER_THRI, iobase+UART_IER);
-
- spin_unlock_irqrestore(&self->lock, flags);
 }
 
 void irport_stop(struct irport_cb *self)
 {
- unsigned long flags;
         int iobase;
 
         iobase = self->io.sir_base;
 
- spin_lock_irqsave(&self->lock, flags);
+ /* We can't lock, we may be called from a FIR driver - Jean II */
 
         /* Reset UART */
         outb(0, iobase+UART_MCR);
         
         /* Turn off interrupts */
         outb(0, iobase+UART_IER);
-
- spin_unlock_irqrestore(&self->lock, flags);
 }
 
 /*
@@ -339,27 +333,28 @@ int irport_probe(int iobase)
  *
  * Set speed of IrDA port to specified baudrate
  *
+ * This function should be called with irq off and spin-lock.
  */
 void irport_change_speed(void *priv, __u32 speed)
 {
         struct irport_cb *self = (struct irport_cb *) priv;
- unsigned long flags;
         int iobase;
         int fcr; /* FIFO control reg */
         int lcr; /* Line control reg */
         int divisor;
 
- IRDA_DEBUG(0, __FUNCTION__ "(), Setting speed to: %d\n", speed);
-
         ASSERT(self != NULL, return;);
 
+ IRDA_DEBUG(1, "%s(), Setting speed to: %d - iobase=%#x\n",
+ __FUNCTION__, speed, self->io.sir_base);
+
+ /* We can't lock, we may be called from a FIR driver - Jean II */
+
         iobase = self->io.sir_base;
         
         /* Update accounting for new speed */
         self->io.speed = speed;
 
- spin_lock_irqsave(&self->lock, flags);
-
         /* Turn off interrupts */
         outb(0, iobase+UART_IER);
 
@@ -387,9 +382,9 @@ void irport_change_speed(void *priv, __u
         outb(fcr, iobase+UART_FCR); /* Enable FIFO's */
 
         /* Turn on interrups */
- outb(/*UART_IER_RLSI|*/UART_IER_RDI/*|UART_IER_THRI*/, iobase+UART_IER);
-
- spin_unlock_irqrestore(&self->lock, flags);
+ /* This will generate a fata interrupt storm.
+ * People calling us will do that properly - Jean II */
+ //outb(/*UART_IER_RLSI|*/UART_IER_RDI/*|UART_IER_THRI*/, iobase+UART_IER);
 }
 
 /*
@@ -397,11 +392,14 @@ void irport_change_speed(void *priv, __u
  *
  * State machine for changing speed of the device. We do it this way since
  * we cannot use schedule_timeout() when we are in interrupt context
+ *
  */
 int __irport_change_speed(struct irda_task *task)
 {
         struct irport_cb *self;
         __u32 speed = (__u32) task->param;
+ unsigned long flags = 0;
+ int wasunlocked = 0;
         int ret = 0;
 
         IRDA_DEBUG(2, __FUNCTION__ "(), <%ld>\n", jiffies);
@@ -410,6 +408,17 @@ int __irport_change_speed(struct irda_ta
 
         ASSERT(self != NULL, return -1;);
 
+ /* Locking notes : this function may be called from irq context with
+ * spinlock, via irport_write_wakeup(), or from non-interrupt without
+ * spinlock (from the task timer). Yuck !
+ * This is ugly, and unsafe is the spinlock is not already aquired.
+ * This will be fixed when irda-task get rewritten.
+ * Jean II */
+ if (!spin_is_locked(&self->lock)) {
+ spin_lock_irqsave(&self->lock, flags);
+ wasunlocked = 1;
+ }
+
         switch (task->state) {
         case IRDA_TASK_INIT:
         case IRDA_TASK_WAIT:
@@ -462,6 +471,11 @@ int __irport_change_speed(struct irda_ta
                 ret = -1;
                 break;
         }
+ /* Put stuff in the sate we found them - Jean II */
+ if(wasunlocked) {
+ spin_unlock_irqrestore(&self->lock, flags);
+ }
+
         return ret;
 }
 
@@ -491,6 +505,9 @@ static void irport_write_wakeup(struct i
                                       self->tx_buff.data, self->tx_buff.len);
                 self->tx_buff.data += actual;
                 self->tx_buff.len -= actual;
+
+ /* Turn on transmit finished interrupt. */
+ outb(UART_IER_THRI, iobase+UART_IER);
         } else {
                 /*
                  * Now serial buffer is almost free & we can start
@@ -498,11 +515,12 @@ static void irport_write_wakeup(struct i
                  * if we need to change the speed of the hardware
                  */
                 if (self->new_speed) {
- IRDA_DEBUG(5, __FUNCTION__ "(), Changing speed!\n");
+ IRDA_DEBUG(5, "%s(), Changing speed!\n", __FUNCTION__);
                         irda_task_execute(self, __irport_change_speed,
                                           irport_change_speed_complete,
                                           NULL, (void *) self->new_speed);
                         self->new_speed = 0;
+ IRDA_DEBUG(5, "%s(), Speed changed!\n", __FUNCTION__ );
                 } else {
                         /* Tell network layer that we want more frames */
                         netif_wake_queue(self->netdev);
@@ -563,7 +581,7 @@ static int irport_change_speed_complete(
 {
         struct irport_cb *self;
 
- IRDA_DEBUG(0, __FUNCTION__ "()\n");
+ IRDA_DEBUG(1, __FUNCTION__ "()\n");
 
         self = (struct irport_cb *) task->instance;
 
@@ -589,13 +607,19 @@ static void irport_timeout(struct net_de
 {
         struct irport_cb *self;
         int iobase;
+ unsigned long flags;
 
         self = (struct irport_cb *) dev->priv;
         iobase = self->io.sir_base;
         
         WARNING("%s: transmit timed out\n", dev->name);
+ spin_lock_irqsave(&self->lock, flags);
         irport_start(self);
         self->change_speed(self->priv, self->io.speed);
+ /* This will re-enable irqs */
+ outb(/*UART_IER_RLSI|*/UART_IER_RDI/*|UART_IER_THRI*/, iobase+UART_IER);
+ spin_unlock_irqrestore(&self->lock, flags);
+
         dev->trans_start = jiffies;
         netif_wake_queue(dev);
 }
@@ -614,7 +638,7 @@ int irport_hard_xmit(struct sk_buff *skb
         int iobase;
         s32 speed;
 
- IRDA_DEBUG(0, __FUNCTION__ "()\n");
+ IRDA_DEBUG(1, __FUNCTION__ "()\n");
 
         ASSERT(dev != NULL, return 0;);
         
@@ -625,22 +649,25 @@ int irport_hard_xmit(struct sk_buff *skb
 
         netif_stop_queue(dev);
         
+ /* Make sure tests *& speed change are atomic */
+ spin_lock_irqsave(&self->lock, flags);
+
         /* Check if we need to change the speed */
         speed = irda_get_next_speed(skb);
         if ((speed != self->io.speed) && (speed != -1)) {
                 /* Check for empty frame */
                 if (!skb->len) {
+ /* Better go there already locked - Jean II */
                         irda_task_execute(self, __irport_change_speed,
                                           irport_change_speed_complete,
                                           NULL, (void *) speed);
+ spin_unlock_irqrestore(&self->lock, flags);
                         dev_kfree_skb(skb);
                         return 0;
                 } else
                         self->new_speed = speed;
         }
 
- spin_lock_irqsave(&self->lock, flags);
-
         /* Init tx buffer */
         self->tx_buff.data = self->tx_buff.head;
 
@@ -771,8 +798,9 @@ int irport_net_open(struct net_device *d
         struct irport_cb *self;
         int iobase;
         char hwname[16];
+ unsigned long flags;
 
- IRDA_DEBUG(0, __FUNCTION__ "()\n");
+ IRDA_DEBUG(1, __FUNCTION__ "()\n");
         
         ASSERT(dev != NULL, return -1;);
         self = (struct irport_cb *) dev->priv;
@@ -786,7 +814,9 @@ int irport_net_open(struct net_device *d
                 return -EAGAIN;
         }
 
+ spin_lock_irqsave(&self->lock, flags);
         irport_start(self);
+ spin_unlock_irqrestore(&self->lock, flags);
 
 
         /* Give self a hardware name */
@@ -818,6 +848,7 @@ int irport_net_close(struct net_device *
 {
         struct irport_cb *self;
         int iobase;
+ unsigned long flags;
 
         IRDA_DEBUG(4, __FUNCTION__ "()\n");
 
@@ -836,7 +867,9 @@ int irport_net_close(struct net_device *
                 irlap_close(self->irlap);
         self->irlap = NULL;
 
+ spin_lock_irqsave(&self->lock, flags);
         irport_stop(self);
+ spin_unlock_irqrestore(&self->lock, flags);
 
         free_irq(self->io.irq, dev);
 
@@ -951,10 +984,6 @@ static int irport_net_ioctl(struct net_d
 
         IRDA_DEBUG(2, __FUNCTION__ "(), %s, (cmd=0x%X)\n", dev->name, cmd);
         
- /* Disable interrupts & save flags */
- save_flags(flags);
- cli();
-
         switch (cmd) {
         case SIOCSBANDWIDTH: /* Set bandwidth */
                 if (!capable(CAP_NET_ADMIN))
@@ -979,14 +1008,16 @@ static int irport_net_ioctl(struct net_d
                 dongle->write = irport_raw_write;
                 dongle->set_dtr_rts = irport_set_dtr_rts;
                 
- self->dongle = dongle;
-
                 /* Now initialize the dongle! */
                 dongle->issue->open(dongle, &self->qos);
                 
                 /* Reset dongle */
                 irda_task_execute(dongle, dongle->issue->reset, NULL, NULL,
                                   NULL);
+
+ /* Make dongle available to driver only now to avoid
+ * race conditions - Jean II */
+ self->dongle = dongle;
                 break;
         case SIOCSMEDIABUSY: /* Set media busy */
                 if (!capable(CAP_NET_ADMIN)) {
@@ -1005,13 +1036,14 @@ static int irport_net_ioctl(struct net_d
                         break;
                 }
 
+ /* No real need to lock... */
+ spin_lock_irqsave(&self->lock, flags);
                 irport_set_dtr_rts(dev, irq->ifr_dtr, irq->ifr_rts);
+ spin_unlock_irqrestore(&self->lock, flags);
                 break;
         default:
                 ret = -EOPNOTSUPP;
         }
-
- restore_flags(flags);
         
         return ret;
 }
diff -u -p -r linux/drivers/net/irda-d6/irtty.c linux/drivers/net/irda/irtty.c
--- linux/drivers/net/irda-d6/irtty.c Mon Aug 19 14:41:00 2002
+++ linux/drivers/net/irda/irtty.c Thu Aug 29 10:12:38 2002
@@ -74,8 +74,10 @@ char *driver_name = "irtty";
 int __init irtty_init(void)
 {
         int status;
-
- irtty = hashbin_new( HB_LOCAL);
+
+ /* Probably no need to lock here because all operations done in
+ * open()/close() which are already safe - Jean II */
+ irtty = hashbin_new( HB_NOLOCK);
         if ( irtty == NULL) {
                 printk( KERN_WARNING "IrDA: Can't allocate irtty hashbin!\n");
                 return -ENOMEM;
@@ -163,6 +165,7 @@ static int irtty_open(struct tty_struct
                 return -ENOMEM;
         }
         memset(self, 0, sizeof(struct irtty_cb));
+ spin_lock_init(&self->lock);
         
         self->tty = tty;
         tty->disc_data = self;
@@ -266,11 +269,12 @@ static int irtty_open(struct tty_struct
 static void irtty_close(struct tty_struct *tty)
 {
         struct irtty_cb *self = (struct irtty_cb *) tty->disc_data;
+ unsigned long flags;
         
         /* First make sure we're connected. */
         ASSERT(self != NULL, return;);
         ASSERT(self->magic == IRTTY_MAGIC, return;);
-
+
         /* Stop tty */
         tty->flags &= ~(1 << TTY_DO_WRITE_WAKEUP);
         tty->disc_data = 0;
@@ -287,6 +291,11 @@ static void irtty_close(struct tty_struc
                 rtnl_unlock();
         }
         
+ self = hashbin_remove(irtty, (int) self, NULL);
+
+ /* Protect access to self->task and self->?x_buff - Jean II */
+ spin_lock_irqsave(&self->lock, flags);
+
         /* Remove speed changing task if any */
         if (self->task)
                 irda_task_delete(self->task);
@@ -294,13 +303,12 @@ static void irtty_close(struct tty_struc
         self->tty = NULL;
         self->magic = 0;
         
- self = hashbin_remove(irtty, (int) self, NULL);
-
         if (self->tx_buff.head)
                 kfree(self->tx_buff.head);
         
         if (self->rx_buff.head)
                 kfree(self->rx_buff.head);
+ spin_unlock_irqrestore(&self->lock, flags);
         
         kfree(self);
         
@@ -326,6 +334,7 @@ static void irtty_stop_receiver(struct i
         else
                 cflag |= CREAD;
 
+ /* This is unsafe, but currently under discussion - Jean II */
         self->tty->termios->c_cflag = cflag;
         self->tty->driver.set_termios(self->tty, &old_termios);
 }
@@ -378,6 +387,7 @@ static void __irtty_change_speed(struct
                 break;
         }
 
+ /* This is unsafe, but currently under discussion - Jean II */
         self->tty->termios->c_cflag = cflag;
         self->tty->driver.set_termios(self->tty, &old_termios);
 
@@ -393,6 +403,7 @@ static void __irtty_change_speed(struct
 static int irtty_change_speed(struct irda_task *task)
 {
         struct irtty_cb *self;
+ unsigned long flags;
         __u32 speed = (__u32) task->param;
         int ret = 0;
 
@@ -401,12 +412,17 @@ static int irtty_change_speed(struct ird
         self = (struct irtty_cb *) task->instance;
         ASSERT(self != NULL, return -1;);
 
+ /* Protect access to self->task - Jean II */
+ spin_lock_irqsave(&self->lock, flags);
+
         /* Check if busy */
         if (self->task && self->task != task) {
                 IRDA_DEBUG(0, __FUNCTION__ "(), busy!\n");
+ spin_unlock_irqrestore(&self->lock, flags);
                 return MSECS_TO_JIFFIES(10);
         } else
                 self->task = task;
+ spin_unlock_irqrestore(&self->lock, flags);
 
         switch (task->state) {
         case IRDA_TASK_INIT:
@@ -501,6 +517,7 @@ static int irtty_ioctl(struct tty_struct
         switch (cmd) {
         case TCGETS:
         case TCGETA:
+ /* Unsure about locking here, to check - Jean II */
                 return n_tty_ioctl(tty, (struct file *) file, cmd,
                                    (unsigned long) arg);
                 break;
@@ -516,15 +533,16 @@ static int irtty_ioctl(struct tty_struct
                 dongle->write = irtty_raw_write;
                 dongle->set_dtr_rts = irtty_set_dtr_rts;
                 
- /* Bind dongle */
- self->dongle = dongle;
-
                 /* Now initialize the dongle! */
                 dongle->issue->open(dongle, &self->qos);
                 
                 /* Reset dongle */
                 irda_task_execute(dongle, dongle->issue->reset, NULL, NULL,
                                   NULL);
+
+ /* Make dongle available to driver only now to avoid
+ * race conditions - Jean II */
+ self->dongle = dongle;
                 break;
         case IRTTY_IOCGET:
                 ASSERT(self->netdev != NULL, return -1;);
@@ -559,6 +577,9 @@ static void irtty_receive_buf(struct tty
                 return;
         }
 
+ // Are we in interrupt context ? What locking is done ? - Jean II
+ //spin_lock_irqsave(&self->lock, flags);
+
         /* Read the characters out of the buffer */
          while (count--) {
                 /*
@@ -589,6 +610,7 @@ static void irtty_receive_buf(struct tty
                         break;
                 }
         }
+ //spin_unlock_irqrestore(&self->lock, flags);
 }
 
 /*
@@ -626,11 +648,13 @@ static int irtty_hard_xmit(struct sk_buf
         struct irtty_cb *self;
         int actual = 0;
         __s32 speed;
+ unsigned long flags;
 
         self = (struct irtty_cb *) dev->priv;
         ASSERT(self != NULL, return 0;);
 
- /* Lock transmit buffer */
+ /* Lock transmit buffer
+ * this serialise operations, no need to spinlock - Jean II */
         netif_stop_queue(dev);
         
         /* Check if we need to change the speed */
@@ -647,6 +671,9 @@ static int irtty_hard_xmit(struct sk_buf
                         self->new_speed = speed;
         }
 
+ /* Protect access to self->tx_buff - Jean II */
+ spin_lock_irqsave(&self->lock, flags);
+
         /* Init tx buffer*/
         self->tx_buff.data = self->tx_buff.head;
         
@@ -667,6 +694,8 @@ static int irtty_hard_xmit(struct sk_buf
         self->tx_buff.data += actual;
         self->tx_buff.len -= actual;
 
+ spin_unlock_irqrestore(&self->lock, flags);
+
         dev_kfree_skb(skb);
 
         return 0;
@@ -695,6 +724,7 @@ static void irtty_write_wakeup(struct tt
 {
         struct irtty_cb *self = (struct irtty_cb *) tty->disc_data;
         int actual = 0;
+ unsigned long flags;
         
         /*
          * First make sure we're connected.
@@ -702,6 +732,11 @@ static void irtty_write_wakeup(struct tt
         ASSERT(self != NULL, return;);
         ASSERT(self->magic == IRTTY_MAGIC, return;);
 
+ /* Protected via netif_stop_queue(dev); - Jean II */
+
+ /* Protect access to self->tx_buff - Jean II */
+ spin_lock_irqsave(&self->lock, flags);
+
         /* Finished with frame? */
         if (self->tx_buff.len > 0) {
                 /* Write data left in transmit buffer */
@@ -710,6 +745,7 @@ static void irtty_write_wakeup(struct tt
 
                 self->tx_buff.data += actual;
                 self->tx_buff.len -= actual;
+ spin_unlock_irqrestore(&self->lock, flags);
         } else {
                 /*
                  * Now serial buffer is almost free & we can start
@@ -721,6 +757,9 @@ static void irtty_write_wakeup(struct tt
 
                 tty->flags &= ~(1 << TTY_DO_WRITE_WAKEUP);
 
+ /* Don't change speed with irq off */
+ spin_unlock_irqrestore(&self->lock, flags);
+
                 if (self->new_speed) {
                         IRDA_DEBUG(5, __FUNCTION__ "(), Changing speed!\n");
                         irda_task_execute(self, irtty_change_speed,
@@ -755,12 +794,17 @@ static int irtty_set_dtr_rts(struct net_
 {
         struct irtty_cb *self;
         struct tty_struct *tty;
+ //unsigned long flags;
         mm_segment_t fs;
         int arg = 0;
 
         self = (struct irtty_cb *) dev->priv;
         tty = self->tty;
 
+ /* Was protected in ioctl handler, but the serial driver doesn't
+ * like it. This may need to change. - Jean II */
+ //spin_lock_irqsave(&self->lock, flags);
+
 #ifdef TIOCM_OUT2 /* Not defined for ARM */
         arg = TIOCM_OUT2;
 #endif
@@ -780,11 +824,14 @@ static int irtty_set_dtr_rts(struct net_
         fs = get_fs();
         set_fs(get_ds());
         
+ /* This is probably unsafe, but currently under discussion - Jean II */
         if (tty->driver.ioctl(tty, NULL, TIOCMSET, (unsigned long) &arg)) {
                 IRDA_DEBUG(2, __FUNCTION__ "(), error doing ioctl!\n");
         }
         set_fs(fs);
 
+ //spin_unlock_irqrestore(&self->lock, flags);
+
         return 0;
 }
 
@@ -799,13 +846,17 @@ static int irtty_set_dtr_rts(struct net_
 int irtty_set_mode(struct net_device *dev, int mode)
 {
         struct irtty_cb *self;
+ unsigned long flags;
 
         self = (struct irtty_cb *) dev->priv;
 
         ASSERT(self != NULL, return -1;);
 
         IRDA_DEBUG(2, __FUNCTION__ "(), mode=%s\n", infrared_mode[mode]);
-
+
+ /* Protect access to self->rx_buff - Jean II */
+ spin_lock_irqsave(&self->lock, flags);
+
         /* save status for driver */
         self->mode = mode;
         
@@ -814,6 +865,8 @@ int irtty_set_mode(struct net_device *de
         self->rx_buff.len = 0;
         self->rx_buff.state = OUTSIDE_FRAME;
 
+ spin_unlock_irqrestore(&self->lock, flags);
+
         return 0;
 }
 
@@ -955,7 +1008,6 @@ static int irtty_net_ioctl(struct net_de
         struct if_irda_req *irq = (struct if_irda_req *) rq;
         struct irtty_cb *self;
         dongle_t *dongle;
- unsigned long flags;
         int ret = 0;
 
         ASSERT(dev != NULL, return -1;);
@@ -971,8 +1023,7 @@ static int irtty_net_ioctl(struct net_de
          * irda_device_dongle_init() can't be locked.
          * irda_task_execute() doesn't need to be locked (but
          * irtty_change_speed() should protect itself).
- * As this driver doesn't have spinlock protection, keep
- * old fashion locking :-(
+ * Other calls protect themselves.
          * Jean II
          */
         
@@ -1025,20 +1076,14 @@ static int irtty_net_ioctl(struct net_de
                 if (!capable(CAP_NET_ADMIN))
                         ret = -EPERM;
                 else {
- save_flags(flags);
- cli();
                         irtty_set_dtr_rts(dev, irq->ifr_dtr, irq->ifr_rts);
- restore_flags(flags);
                 }
                 break;
         case SIOCSMODE:
                 if (!capable(CAP_NET_ADMIN))
                         ret = -EPERM;
                 else {
- save_flags(flags);
- cli();
                         irtty_set_mode(dev, irq->ifr_mode);
- restore_flags(flags);
                 }
                 break;
         default:
diff -u -p -r linux/drivers/net/irda-d6/nsc-ircc.c linux/drivers/net/irda/nsc-ircc.c
--- linux/drivers/net/irda-d6/nsc-ircc.c Fri Aug 23 11:07:06 2002
+++ linux/drivers/net/irda/nsc-ircc.c Fri Aug 23 11:42:23 2002
@@ -870,7 +870,6 @@ static void nsc_ircc_init_dongle_interfa
  */
 static void nsc_ircc_change_dongle_speed(int iobase, int speed, int dongle_id)
 {
- unsigned long flags;
         __u8 bank;
 
         /* Save current bank */
@@ -916,11 +915,10 @@ static void nsc_ircc_change_dongle_speed
                 outb(0x01, iobase+4);
 
                 if (speed == 4000000) {
- save_flags(flags);
- cli();
+ /* There was a cli() there, but we now are already
+ * under spin_lock_irqsave() - JeanII */
                         outb(0x81, iobase+4);
                         outb(0x80, iobase+4);
- restore_flags(flags);
                 } else
                         outb(0x00, iobase+4);
                 break;
@@ -2013,33 +2011,30 @@ static int nsc_ircc_net_ioctl(struct net
 
         IRDA_DEBUG(2, __FUNCTION__ "(), %s, (cmd=0x%X)\n", dev->name, cmd);
         
- /* Disable interrupts & save flags */
- save_flags(flags);
- cli();
-
         switch (cmd) {
         case SIOCSBANDWIDTH: /* Set bandwidth */
                 if (!capable(CAP_NET_ADMIN)) {
                         ret = -EPERM;
- goto out;
+ break;
                 }
+ spin_lock_irqsave(&self->lock, flags);
                 nsc_ircc_change_speed(self, irq->ifr_baudrate);
+ spin_unlock_irqrestore(&self->lock, flags);
                 break;
         case SIOCSMEDIABUSY: /* Set media busy */
                 if (!capable(CAP_NET_ADMIN)) {
                         ret = -EPERM;
- goto out;
+ break;
                 }
                 irda_device_set_media_busy(self->netdev, TRUE);
                 break;
         case SIOCGRECEIVING: /* Check if we are receiving right now */
+ /* This is already protected */
                 irq->ifr_receiving = nsc_ircc_is_receiving(self);
                 break;
         default:
                 ret = -EOPNOTSUPP;
         }
-out:
- restore_flags(flags);
         return ret;
 }
 
diff -u -p -r linux/drivers/net/irda-d6/smc-ircc.c linux/drivers/net/irda/smc-ircc.c
--- linux/drivers/net/irda-d6/smc-ircc.c Mon Aug 19 14:41:00 2002
+++ linux/drivers/net/irda/smc-ircc.c Fri Aug 23 15:46:03 2002
@@ -431,6 +431,7 @@ static int __init ircc_open(unsigned int
         struct ircc_cb *self;
         struct irport_cb *irport;
         unsigned char low, high, chip, config, dma, irq, version;
+ unsigned long flags;
 
 
         IRDA_DEBUG(0, __FUNCTION__ "\n");
@@ -484,7 +485,6 @@ static int __init ircc_open(unsigned int
                 return -ENOMEM;
         }
         memset(self, 0, sizeof(struct ircc_cb));
- spin_lock_init(&self->lock);
 
         /* Max DMA buffer size needed = (data_size + 6) * (window_size) + 6; */
         self->rx_buff.truesize = 4000;
@@ -555,6 +555,9 @@ static int __init ircc_open(unsigned int
 
         request_region(self->io->fir_base, CHIP_IO_EXTENT, driver_name);
 
+ /* Don't allow irport to change under us - Jean II */
+ spin_lock_irqsave(&self->irport->lock, flags);
+
         /* Initialize QoS for this device */
         irda_init_max_qos_capabilies(&irport->qos);
         
@@ -581,6 +584,7 @@ static int __init ircc_open(unsigned int
         self->netdev->stop = &ircc_net_close;
 
         irport_start(self->irport);
+ spin_unlock_irqrestore(&self->irport->lock, flags);
 
         self->pmdev = pm_register(PM_SYS_DEV, PM_SYS_IRDA, ircc_pmproc);
         if (self->pmdev)
@@ -598,6 +602,7 @@ static int __init ircc_open(unsigned int
  *
  * Change the speed of the device
  *
+ * This function should be called with irq off and spin-lock.
  */
 static void ircc_change_speed(void *priv, u32 speed)
 {
@@ -658,6 +663,7 @@ static void ircc_change_speed(void *priv
 
         /* Make special FIR init if necessary */
         if (speed > 115200) {
+ /* No need to lock, already locked - Jean II */
                 irport_stop(self->irport);
 
                 /* Install FIR transmit handler */
@@ -674,6 +680,7 @@ static void ircc_change_speed(void *priv
         } else {
                 /* Install SIR transmit handler */
                 dev->hard_start_xmit = &irport_hard_xmit;
+ /* No need to lock, already locked - Jean II */
                 irport_start(self->irport);
                 
                 IRDA_DEBUG(0, __FUNCTION__
@@ -727,20 +734,26 @@ static int ircc_hard_xmit(struct sk_buff
 
         netif_stop_queue(dev);
 
+ /* Make sure tests *& speed change are atomic */
+ spin_lock_irqsave(&self->irport->lock, flags);
+
+ /* Note : you should make sure that speed changes are not going
+ * to corrupt any outgoing frame. Look at nsc-ircc for the gory
+ * details - Jean II */
+
         /* Check if we need to change the speed after this frame */
         speed = irda_get_next_speed(skb);
         if ((speed != self->io->speed) && (speed != -1)) {
                 /* Check for empty frame */
                 if (!skb->len) {
                         ircc_change_speed(self, speed);
+ spin_unlock_irqrestore(&self->irport->lock, flags);
                         dev_kfree_skb(skb);
                         return 0;
                 } else
                         self->new_speed = speed;
         }
         
- spin_lock_irqsave(&self->lock, flags);
-
         memcpy(self->tx_buff.head, skb->data, skb->len);
 
         self->tx_buff.len = skb->len;
@@ -763,7 +776,7 @@ static int ircc_hard_xmit(struct sk_buff
                 /* Transmit frame */
                 ircc_dma_xmit(self, iobase, 0);
         }
- spin_unlock_irqrestore(&self->lock, flags);
+ spin_unlock_irqrestore(&self->irport->lock, flags);
         dev_kfree_skb(skb);
 
         return 0;
@@ -985,12 +998,13 @@ static void ircc_interrupt(int irq, void
 
         /* Check if we should use the SIR interrupt handler */
         if (self->io->speed < 576000) {
+ /* Will spinlock itself - Jean II */
                 irport_interrupt(irq, dev_id, regs);
                 return;
         }
         iobase = self->io->fir_base;
 
- spin_lock(&self->lock);
+ spin_lock(&self->irport->lock);
 
         register_bank(iobase, 0);
         iir = inb(iobase+IRCC_IIR);
@@ -1013,7 +1027,7 @@ static void ircc_interrupt(int irq, void
         register_bank(iobase, 0);
         outb(IRCC_IER_ACTIVE_FRAME|IRCC_IER_EOM, iobase+IRCC_IER);
 
- spin_unlock(&self->lock);
+ spin_unlock(&self->irport->lock);
 }
 
 #if 0 /* unused */
@@ -1128,17 +1142,15 @@ static void ircc_suspend(struct ircc_cb
 
 static void ircc_wakeup(struct ircc_cb *self)
 {
- unsigned long flags;
-
         if (!self->io->suspended)
                 return;
 
- save_flags(flags);
- cli();
+ /* The code was doing a "cli()" here, but this can't be right.
+ * If you need protection, do it in net_open with a spinlock
+ * or give a good reason. - Jean II */
 
         ircc_net_open(self->netdev);
         
- restore_flags(flags);
         MESSAGE("%s, Waking up\n", driver_name);
 }
 
@@ -1174,6 +1186,7 @@ static int __exit ircc_close(struct ircc
 
         iobase = self->irport->io.fir_base;
 
+ /* This will destroy irport */
         irport_close(self->irport);
 
         /* Stop interrupts */
@@ -1187,6 +1200,7 @@ static int __exit ircc_close(struct ircc
         outb(IRCC_CFGA_IRDA_SIR_A|IRCC_CFGA_TX_POLARITY, iobase+IRCC_SCE_CFGA);
         outb(IRCC_CFGB_IR, iobase+IRCC_SCE_CFGB);
 #endif
+
         /* Release the PORT that this driver is using */
         IRDA_DEBUG(0, __FUNCTION__ "(), releasing 0x%03x\n", iobase);
 
diff -u -p -r linux/drivers/net/irda-d6/w83977af_ir.c linux/drivers/net/irda/w83977af_ir.c
--- linux/drivers/net/irda-d6/w83977af_ir.c Mon Aug 19 14:41:00 2002
+++ linux/drivers/net/irda/w83977af_ir.c Fri Aug 23 12:00:44 2002
@@ -175,6 +175,7 @@ int w83977af_open(int i, unsigned int io
                 return -ENOMEM;
         }
         memset(self, 0, sizeof(struct w83977af_ir));
+ spin_lock_init(&self->lock);
    
         /* Need to store self somewhere */
         dev_self[i] = self;
@@ -603,8 +604,7 @@ static void w83977af_dma_write(struct w8
         switch_bank(iobase, SET2);
         outb(ADCR1_D_CHSW|/*ADCR1_DMA_F|*/ADCR1_ADV_SL, iobase+ADCR1);
 #ifdef CONFIG_NETWINDER_TX_DMA_PROBLEMS
- save_flags(flags);
- cli();
+ spin_lock_irqsave(&self->lock, flags);
 
         disable_dma(self->io.dma);
         clear_dma_ff(self->io.dma);
@@ -623,7 +623,7 @@ static void w83977af_dma_write(struct w8
         hcr = inb(iobase+HCR);
         outb(hcr | HCR_EN_DMA, iobase+HCR);
         enable_dma(self->io.dma);
- restore_flags(flags);
+ spin_unlock_irqrestore(&self->lock, flags);
 #else
         outb(inb(iobase+HCR) | HCR_EN_DMA | HCR_TX_WT, iobase+HCR);
 #endif
@@ -761,8 +761,7 @@ int w83977af_dma_receive(struct w83977af
         self->rx_buff.data = self->rx_buff.head;
 
 #ifdef CONFIG_NETWINDER_RX_DMA_PROBLEMS
- save_flags(flags);
- cli();
+ spin_lock_irqsave(&self->lock, flags);
 
         disable_dma(self->io.dma);
         clear_dma_ff(self->io.dma);
@@ -788,7 +787,7 @@ int w83977af_dma_receive(struct w83977af
         hcr = inb(iobase+HCR);
         outb(hcr | HCR_EN_DMA, iobase+HCR);
         enable_dma(self->io.dma);
- restore_flags(flags);
+ spin_unlock_irqrestore(&self->lock, flags);
 #else
         outb(inb(iobase+HCR) | HCR_EN_DMA, iobase+HCR);
 #endif
@@ -1334,10 +1333,8 @@ static int w83977af_net_ioctl(struct net
 
         IRDA_DEBUG(2, __FUNCTION__ "(), %s, (cmd=0x%X)\n", dev->name, cmd);
         
- /* Disable interrupts & save flags */
- save_flags(flags);
- cli();
-
+ spin_lock_irqsave(&self->lock, flags);
+
         switch (cmd) {
         case SIOCSBANDWIDTH: /* Set bandwidth */
                 if (!capable(CAP_NET_ADMIN)) {
@@ -1360,7 +1357,7 @@ static int w83977af_net_ioctl(struct net
                 ret = -EOPNOTSUPP;
         }
 out:
- restore_flags(flags);
+ spin_unlock_irqrestore(&self->lock, flags);
         return ret;
 }
 
-
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This archive was generated by hypermail 2b29 : Sat Aug 31 2002 - 22:00:29 EST