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[PATCH] USB: add ability for usb-serial drivers to determine if their write urb is currently being used.

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This removes a lot of racy and buggy code by trying to check the status of the urb.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Greg Kroah-Hartman 2005-04-23 12:49:16 -07:00
parent f4df0e334a
commit 507ca9bc04
10 changed files with 85 additions and 46 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

17
drivers/usb/serial/cyberjack.c
View file

@ -213,10 +213,14 @@ static int cyberjack_write (struct usb_serial_port *port, const unsigned char *b
return (0);
}
if (port->write_urb->status == -EINPROGRESS) {
spin_lock(&port->lock);
if (port->write_urb_busy) {
spin_unlock(&port->lock);
dbg("%s - already writing", __FUNCTION__);
return (0);
return 0;
}
port->write_urb_busy = 1;
spin_unlock(&port->lock);
spin_lock_irqsave(&priv->lock, flags);
@ -224,6 +228,7 @@ static int cyberjack_write (struct usb_serial_port *port, const unsigned char *b
/* To much data for buffer. Reset buffer. */
priv->wrfilled=0;
spin_unlock_irqrestore(&priv->lock, flags);
port->write_urb_busy = 0;
return (0);
}
@ -268,6 +273,7 @@ static int cyberjack_write (struct usb_serial_port *port, const unsigned char *b
priv->wrfilled=0;
priv->wrsent=0;
spin_unlock_irqrestore(&priv->lock, flags);
port->write_urb_busy = 0;
return 0;
}
@ -413,6 +419,7 @@ static void cyberjack_write_bulk_callback (struct urb *urb, struct pt_regs *regs
dbg("%s - port %d", __FUNCTION__, port->number);
port->write_urb_busy = 0;
if (urb->status) {
dbg("%s - nonzero write bulk status received: %d", __FUNCTION__, urb->status);
return;
@ -424,12 +431,6 @@ static void cyberjack_write_bulk_callback (struct urb *urb, struct pt_regs *regs
if( priv->wrfilled ) {
int length, blksize, result;
if (port->write_urb->status == -EINPROGRESS) {
dbg("%s - already writing", __FUNCTION__);
spin_unlock(&priv->lock);
return;
}
dbg("%s - transmitting data (frame n)", __FUNCTION__);
length = ((priv->wrfilled - priv->wrsent) > port->bulk_out_size) ?

22
drivers/usb/serial/generic.c
View file

@ -174,10 +174,14 @@ int usb_serial_generic_write(struct usb_serial_port *port, const unsigned char *
/* only do something if we have a bulk out endpoint */
if (serial->num_bulk_out) {
if (port->write_urb->status == -EINPROGRESS) {
spin_lock(&port->lock);
if (port->write_urb_busy) {
spin_unlock(&port->lock);
dbg("%s - already writing", __FUNCTION__);
return (0);
return 0;
}
port->write_urb_busy = 1;
spin_unlock(&port->lock);
count = (count > port->bulk_out_size) ? port->bulk_out_size : count;
@ -195,17 +199,20 @@ int usb_serial_generic_write(struct usb_serial_port *port, const unsigned char *
usb_serial_generic_write_bulk_callback), port);
/* send the data out the bulk port */
port->write_urb_busy = 1;
result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
if (result)
if (result) {
dev_err(&port->dev, "%s - failed submitting write urb, error %d\n", __FUNCTION__, result);
else
/* don't have to grab the lock here, as we will retry if != 0 */
port->write_urb_busy = 0;
} else
result = count;
return result;
}
/* no bulk out, so return 0 bytes written */
return (0);
return 0;
}
int usb_serial_generic_write_room (struct usb_serial_port *port)
@ -216,7 +223,7 @@ int usb_serial_generic_write_room (struct usb_serial_port *port)
dbg("%s - port %d", __FUNCTION__, port->number);
if (serial->num_bulk_out) {
if (port->write_urb->status != -EINPROGRESS)
if (port->write_urb_busy)
room = port->bulk_out_size;
}
@ -232,7 +239,7 @@ int usb_serial_generic_chars_in_buffer (struct usb_serial_port *port)
dbg("%s - port %d", __FUNCTION__, port->number);
if (serial->num_bulk_out) {
if (port->write_urb->status == -EINPROGRESS)
if (port->write_urb_busy)
chars = port->write_urb->transfer_buffer_length;
}
@ -291,6 +298,7 @@ void usb_serial_generic_write_bulk_callback (struct urb *urb, struct pt_regs *re
dbg("%s - port %d", __FUNCTION__, port->number);
port->write_urb_busy = 0;
if (urb->status) {
dbg("%s - nonzero write bulk status received: %d", __FUNCTION__, urb->status);
return;

5
drivers/usb/serial/ipaq.c
View file

@ -818,11 +818,6 @@ static void ipaq_write_gather(struct usb_serial_port *port)
struct ipaq_packet *pkt, *tmp;
struct urb *urb = port->write_urb;
if (urb->status == -EINPROGRESS) {
/* Should never happen */
err("%s - flushing while urb is active !", __FUNCTION__);
return;
}
room = URBDATA_SIZE;
list_for_each_entry_safe(pkt, tmp, &priv->queue, list) {
count = min(room, (int)(pkt->len - pkt->written));

10
drivers/usb/serial/ipw.c
View file

@ -400,9 +400,14 @@ static int ipw_write(struct usb_serial_port *port, const unsigned char *buf, int
return 0;
}
/* Racy and broken, FIXME properly! */
if (port->write_urb->status == -EINPROGRESS)
spin_lock(&port->lock);
if (port->write_urb_busy) {
spin_unlock(&port->lock);
dbg("%s - already writing", __FUNCTION__);
return 0;
}
port->write_urb_busy = 1;
spin_unlock(&port->lock);
count = min(count, port->bulk_out_size);
memcpy(port->bulk_out_buffer, buf, count);
@ -418,6 +423,7 @@ static int ipw_write(struct usb_serial_port *port, const unsigned char *buf, int
ret = usb_submit_urb(port->write_urb, GFP_ATOMIC);
if (ret != 0) {
port->write_urb_busy = 0;
dbg("%s - usb_submit_urb(write bulk) failed with error = %d", __FUNCTION__, ret);
return ret;
}

14
drivers/usb/serial/ir-usb.c
View file

@ -341,10 +341,14 @@ static int ir_write (struct usb_serial_port *port, const unsigned char *buf, int
if (count == 0)
return 0;
if (port->write_urb->status == -EINPROGRESS) {
dbg ("%s - already writing", __FUNCTION__);
spin_lock(&port->lock);
if (port->write_urb_busy) {
spin_unlock(&port->lock);
dbg("%s - already writing", __FUNCTION__);
return 0;
}
port->write_urb_busy = 1;
spin_unlock(&port->lock);
transfer_buffer = port->write_urb->transfer_buffer;
transfer_size = min(count, port->bulk_out_size - 1);
@ -374,9 +378,10 @@ static int ir_write (struct usb_serial_port *port, const unsigned char *buf, int
port->write_urb->transfer_flags = URB_ZERO_PACKET;
result = usb_submit_urb (port->write_urb, GFP_ATOMIC);
if (result)
if (result) {
port->write_urb_busy = 0;
dev_err(&port->dev, "%s - failed submitting write urb, error %d\n", __FUNCTION__, result);
else
} else
result = transfer_size;
return result;
@ -388,6 +393,7 @@ static void ir_write_bulk_callback (struct urb *urb, struct pt_regs *regs)
dbg("%s - port %d", __FUNCTION__, port->number);
port->write_urb_busy = 0;
if (urb->status) {
dbg("%s - nonzero write bulk status received: %d", __FUNCTION__, urb->status);
return;

13
drivers/usb/serial/keyspan_pda.c
View file

@ -520,9 +520,13 @@ static int keyspan_pda_write(struct usb_serial_port *port,
the TX urb is in-flight (wait until it completes)
the device is full (wait until it says there is room)
*/
if (port->write_urb->status == -EINPROGRESS || priv->tx_throttled ) {
return( 0 );
spin_lock(&port->lock);
if (port->write_urb_busy || priv->tx_throttled) {
spin_unlock(&port->lock);
return 0;
}
port->write_urb_busy = 1;
spin_unlock(&port->lock);
/* At this point the URB is in our control, nobody else can submit it
again (the only sudden transition was the one from EINPROGRESS to
@ -593,6 +597,8 @@ static int keyspan_pda_write(struct usb_serial_port *port,
rc = count;
exit:
if (rc < 0)
port->write_urb_busy = 0;
return rc;
}
@ -602,6 +608,7 @@ static void keyspan_pda_write_bulk_callback (struct urb *urb, struct pt_regs *re
struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
struct keyspan_pda_private *priv;
port->write_urb_busy = 0;
priv = usb_get_serial_port_data(port);
/* queue up a wakeup at scheduler time */
@ -631,7 +638,7 @@ static int keyspan_pda_chars_in_buffer (struct usb_serial_port *port)
/* when throttled, return at least WAKEUP_CHARS to tell select() (via
n_tty.c:normal_poll() ) that we're not writeable. */
if( port->write_urb->status == -EINPROGRESS || priv->tx_throttled )
if (port->write_urb_busy || priv->tx_throttled)
return 256;
return 0;
}

17
drivers/usb/serial/omninet.c
View file

@ -254,10 +254,15 @@ static int omninet_write (struct usb_serial_port *port, const unsigned char *buf
dbg("%s - write request of 0 bytes", __FUNCTION__);
return (0);
}
if (wport->write_urb->status == -EINPROGRESS) {
spin_lock(&port->lock);
if (port->write_urb_busy) {
spin_unlock(&port->lock);
dbg("%s - already writing", __FUNCTION__);
return (0);
return 0;
}
port->write_urb_busy = 1;
spin_unlock(&port->lock);
count = (count > OMNINET_BULKOUTSIZE) ? OMNINET_BULKOUTSIZE : count;
@ -275,9 +280,10 @@ static int omninet_write (struct usb_serial_port *port, const unsigned char *buf
wport->write_urb->dev = serial->dev;
result = usb_submit_urb(wport->write_urb, GFP_ATOMIC);
if (result)
if (result) {
port->write_urb_busy = 0;
err("%s - failed submitting write urb, error %d", __FUNCTION__, result);
else
} else
result = count;
return result;
@ -291,7 +297,7 @@ static int omninet_write_room (struct usb_serial_port *port)
int room = 0; // Default: no room
if (wport->write_urb->status != -EINPROGRESS)
if (wport->write_urb_busy)
room = wport->bulk_out_size - OMNINET_HEADERLEN;
// dbg("omninet_write_room returns %d", room);
@ -306,6 +312,7 @@ static void omninet_write_bulk_callback (struct urb *urb, struct pt_regs *regs)
// dbg("omninet_write_bulk_callback, port %0x\n", port);
port->write_urb_busy = 0;
if (urb->status) {
dbg("%s - nonzero write bulk status received: %d", __FUNCTION__, urb->status);
return;

13
drivers/usb/serial/safe_serial.c
View file

@ -299,10 +299,14 @@ static int safe_write (struct usb_serial_port *port, const unsigned char *buf, i
dbg ("%s - write request of 0 bytes", __FUNCTION__);
return (0);
}
if (port->write_urb->status == -EINPROGRESS) {
dbg ("%s - already writing", __FUNCTION__);
return (0);
spin_lock(&port->lock);
if (port->write_urb_busy) {
spin_unlock(&port->lock);
dbg("%s - already writing", __FUNCTION__);
return 0;
}
port->write_urb_busy = 1;
spin_unlock(&port->lock);
packet_length = port->bulk_out_size; // get max packetsize
@ -354,6 +358,7 @@ static int safe_write (struct usb_serial_port *port, const unsigned char *buf, i
#endif
port->write_urb->dev = port->serial->dev;
if ((result = usb_submit_urb (port->write_urb, GFP_KERNEL))) {
port->write_urb_busy = 0;
err ("%s - failed submitting write urb, error %d", __FUNCTION__, result);
return 0;
}
@ -368,7 +373,7 @@ static int safe_write_room (struct usb_serial_port *port)
dbg ("%s", __FUNCTION__);
if (port->write_urb->status != -EINPROGRESS)
if (port->write_urb_busy)
room = port->bulk_out_size - (safe ? 2 : 0);
if (room) {

1
drivers/usb/serial/usb-serial.c
View file

@ -1047,6 +1047,7 @@ int usb_serial_probe(struct usb_interface *interface,
memset(port, 0x00, sizeof(struct usb_serial_port));
port->number = i + serial->minor;
port->serial = serial;
spin_lock_init(&port->lock);
INIT_WORK(&port->work, usb_serial_port_softint, port);
serial->port[i] = port;
}

3
drivers/usb/serial/usb-serial.h
View file

@ -69,6 +69,7 @@
* usb_serial_port: structure for the specific ports of a device.
* @serial: pointer back to the struct usb_serial owner of this port.
* @tty: pointer to the corresponding tty for this port.
* @lock: spinlock to grab when updating portions of this structure.
* @number: the number of the port (the minor number).
* @interrupt_in_buffer: pointer to the interrupt in buffer for this port.
* @interrupt_in_urb: pointer to the interrupt in struct urb for this port.
@ -98,6 +99,7 @@
struct usb_serial_port {
struct usb_serial * serial;
struct tty_struct * tty;
spinlock_t lock;
unsigned char number;
unsigned char * interrupt_in_buffer;
@ -117,6 +119,7 @@ struct usb_serial_port {
unsigned char * bulk_out_buffer;
int bulk_out_size;
struct urb * write_urb;
int write_urb_busy;
__u8 bulk_out_endpointAddress;
wait_queue_head_t write_wait;