Commit 8e422669 authored by Oliver Neukum's avatar Oliver Neukum Committed by Greg Kroah-Hartman

USB: mutexification of usblp

this patch:
- converts usblp fully to mutex
- makes sleeping interruptible where EINTR can be returned anyway
Signed-off-by: default avatarOliver Neukum <oliver@neukum.name>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent b1cff285
...@@ -130,7 +130,7 @@ MFG:HEWLETT-PACKARD;MDL:DESKJET 970C;CMD:MLC,PCL,PML;CLASS:PRINTER;DESCRIPTION:H ...@@ -130,7 +130,7 @@ MFG:HEWLETT-PACKARD;MDL:DESKJET 970C;CMD:MLC,PCL,PML;CLASS:PRINTER;DESCRIPTION:H
struct usblp { struct usblp {
struct usb_device *dev; /* USB device */ struct usb_device *dev; /* USB device */
struct semaphore sem; /* locks this struct, especially "dev" */ struct mutex mut; /* locks this struct, especially "dev" */
char *writebuf; /* write transfer_buffer */ char *writebuf; /* write transfer_buffer */
char *readbuf; /* read transfer_buffer */ char *readbuf; /* read transfer_buffer */
char *statusbuf; /* status transfer_buffer */ char *statusbuf; /* status transfer_buffer */
...@@ -465,7 +465,7 @@ static long usblp_ioctl(struct file *file, unsigned int cmd, unsigned long arg) ...@@ -465,7 +465,7 @@ static long usblp_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
int twoints[2]; int twoints[2];
int retval = 0; int retval = 0;
down (&usblp->sem); mutex_lock (&usblp->mut);
if (!usblp->present) { if (!usblp->present) {
retval = -ENODEV; retval = -ENODEV;
goto done; goto done;
...@@ -644,14 +644,14 @@ static long usblp_ioctl(struct file *file, unsigned int cmd, unsigned long arg) ...@@ -644,14 +644,14 @@ static long usblp_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
} }
done: done:
up (&usblp->sem); mutex_unlock (&usblp->mut);
return retval; return retval;
} }
static ssize_t usblp_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos) static ssize_t usblp_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
{ {
struct usblp *usblp = file->private_data; struct usblp *usblp = file->private_data;
int timeout, rv, err = 0, transfer_length = 0; int timeout, intr, rv, err = 0, transfer_length = 0;
size_t writecount = 0; size_t writecount = 0;
while (writecount < count) { while (writecount < count) {
...@@ -668,14 +668,16 @@ static ssize_t usblp_write(struct file *file, const char __user *buffer, size_t ...@@ -668,14 +668,16 @@ static ssize_t usblp_write(struct file *file, const char __user *buffer, size_t
if (rv < 0) if (rv < 0)
return writecount ? writecount : -EINTR; return writecount ? writecount : -EINTR;
} }
down (&usblp->sem); intr = mutex_lock_interruptible (&usblp->mut);
if (intr)
return writecount ? writecount : -EINTR;
if (!usblp->present) { if (!usblp->present) {
up (&usblp->sem); mutex_unlock (&usblp->mut);
return -ENODEV; return -ENODEV;
} }
if (usblp->sleeping) { if (usblp->sleeping) {
up (&usblp->sem); mutex_unlock (&usblp->mut);
return writecount ? writecount : -ENODEV; return writecount ? writecount : -ENODEV;
} }
...@@ -687,10 +689,10 @@ static ssize_t usblp_write(struct file *file, const char __user *buffer, size_t ...@@ -687,10 +689,10 @@ static ssize_t usblp_write(struct file *file, const char __user *buffer, size_t
err = usblp->writeurb->status; err = usblp->writeurb->status;
} else } else
err = usblp_check_status(usblp, err); err = usblp_check_status(usblp, err);
up (&usblp->sem); mutex_unlock (&usblp->mut);
/* if the fault was due to disconnect, let khubd's /* if the fault was due to disconnect, let khubd's
* call to usblp_disconnect() grab usblp->sem ... * call to usblp_disconnect() grab usblp->mut ...
*/ */
schedule (); schedule ();
continue; continue;
...@@ -702,7 +704,7 @@ static ssize_t usblp_write(struct file *file, const char __user *buffer, size_t ...@@ -702,7 +704,7 @@ static ssize_t usblp_write(struct file *file, const char __user *buffer, size_t
*/ */
writecount += transfer_length; writecount += transfer_length;
if (writecount == count) { if (writecount == count) {
up(&usblp->sem); mutex_unlock(&usblp->mut);
break; break;
} }
...@@ -714,7 +716,7 @@ static ssize_t usblp_write(struct file *file, const char __user *buffer, size_t ...@@ -714,7 +716,7 @@ static ssize_t usblp_write(struct file *file, const char __user *buffer, size_t
if (copy_from_user(usblp->writeurb->transfer_buffer, if (copy_from_user(usblp->writeurb->transfer_buffer,
buffer + writecount, transfer_length)) { buffer + writecount, transfer_length)) {
up(&usblp->sem); mutex_unlock(&usblp->mut);
return writecount ? writecount : -EFAULT; return writecount ? writecount : -EFAULT;
} }
...@@ -727,10 +729,10 @@ static ssize_t usblp_write(struct file *file, const char __user *buffer, size_t ...@@ -727,10 +729,10 @@ static ssize_t usblp_write(struct file *file, const char __user *buffer, size_t
count = -EIO; count = -EIO;
else else
count = writecount ? writecount : -ENOMEM; count = writecount ? writecount : -ENOMEM;
up (&usblp->sem); mutex_unlock (&usblp->mut);
break; break;
} }
up (&usblp->sem); mutex_unlock (&usblp->mut);
} }
return count; return count;
...@@ -739,12 +741,14 @@ static ssize_t usblp_write(struct file *file, const char __user *buffer, size_t ...@@ -739,12 +741,14 @@ static ssize_t usblp_write(struct file *file, const char __user *buffer, size_t
static ssize_t usblp_read(struct file *file, char __user *buffer, size_t count, loff_t *ppos) static ssize_t usblp_read(struct file *file, char __user *buffer, size_t count, loff_t *ppos)
{ {
struct usblp *usblp = file->private_data; struct usblp *usblp = file->private_data;
int rv; int rv, intr;
if (!usblp->bidir) if (!usblp->bidir)
return -EINVAL; return -EINVAL;
down (&usblp->sem); intr = mutex_lock_interruptible (&usblp->mut);
if (intr)
return -EINTR;
if (!usblp->present) { if (!usblp->present) {
count = -ENODEV; count = -ENODEV;
goto done; goto done;
...@@ -757,9 +761,9 @@ static ssize_t usblp_read(struct file *file, char __user *buffer, size_t count, ...@@ -757,9 +761,9 @@ static ssize_t usblp_read(struct file *file, char __user *buffer, size_t count,
count = -EAGAIN; count = -EAGAIN;
goto done; goto done;
} }
up(&usblp->sem); mutex_unlock(&usblp->mut);
rv = wait_event_interruptible(usblp->wait, usblp->rcomplete || !usblp->present); rv = wait_event_interruptible(usblp->wait, usblp->rcomplete || !usblp->present);
down(&usblp->sem); mutex_lock(&usblp->mut);
if (rv < 0) { if (rv < 0) {
count = -EINTR; count = -EINTR;
goto done; goto done;
...@@ -807,7 +811,7 @@ static ssize_t usblp_read(struct file *file, char __user *buffer, size_t count, ...@@ -807,7 +811,7 @@ static ssize_t usblp_read(struct file *file, char __user *buffer, size_t count,
} }
done: done:
up (&usblp->sem); mutex_unlock (&usblp->mut);
return count; return count;
} }
...@@ -886,7 +890,7 @@ static int usblp_probe(struct usb_interface *intf, ...@@ -886,7 +890,7 @@ static int usblp_probe(struct usb_interface *intf,
goto abort; goto abort;
} }
usblp->dev = dev; usblp->dev = dev;
init_MUTEX (&usblp->sem); mutex_init (&usblp->mut);
init_waitqueue_head(&usblp->wait); init_waitqueue_head(&usblp->wait);
usblp->ifnum = intf->cur_altsetting->desc.bInterfaceNumber; usblp->ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
usblp->intf = intf; usblp->intf = intf;
...@@ -1178,7 +1182,7 @@ static void usblp_disconnect(struct usb_interface *intf) ...@@ -1178,7 +1182,7 @@ static void usblp_disconnect(struct usb_interface *intf)
device_remove_file(&intf->dev, &dev_attr_ieee1284_id); device_remove_file(&intf->dev, &dev_attr_ieee1284_id);
mutex_lock (&usblp_mutex); mutex_lock (&usblp_mutex);
down (&usblp->sem); mutex_lock (&usblp->mut);
usblp->present = 0; usblp->present = 0;
usb_set_intfdata (intf, NULL); usb_set_intfdata (intf, NULL);
...@@ -1187,7 +1191,7 @@ static void usblp_disconnect(struct usb_interface *intf) ...@@ -1187,7 +1191,7 @@ static void usblp_disconnect(struct usb_interface *intf)
usblp->writebuf, usblp->writeurb->transfer_dma); usblp->writebuf, usblp->writeurb->transfer_dma);
usb_buffer_free (usblp->dev, USBLP_BUF_SIZE, usb_buffer_free (usblp->dev, USBLP_BUF_SIZE,
usblp->readbuf, usblp->readurb->transfer_dma); usblp->readbuf, usblp->readurb->transfer_dma);
up (&usblp->sem); mutex_unlock (&usblp->mut);
if (!usblp->used) if (!usblp->used)
usblp_cleanup (usblp); usblp_cleanup (usblp);
...@@ -1200,11 +1204,11 @@ static int usblp_suspend (struct usb_interface *intf, pm_message_t message) ...@@ -1200,11 +1204,11 @@ static int usblp_suspend (struct usb_interface *intf, pm_message_t message)
/* this races against normal access and open */ /* this races against normal access and open */
mutex_lock (&usblp_mutex); mutex_lock (&usblp_mutex);
down (&usblp->sem); mutex_lock (&usblp->mut);
/* we take no more IO */ /* we take no more IO */
usblp->sleeping = 1; usblp->sleeping = 1;
usblp_unlink_urbs(usblp); usblp_unlink_urbs(usblp);
up (&usblp->sem); mutex_unlock (&usblp->mut);
mutex_unlock (&usblp_mutex); mutex_unlock (&usblp_mutex);
return 0; return 0;
...@@ -1216,12 +1220,12 @@ static int usblp_resume (struct usb_interface *intf) ...@@ -1216,12 +1220,12 @@ static int usblp_resume (struct usb_interface *intf)
int r; int r;
mutex_lock (&usblp_mutex); mutex_lock (&usblp_mutex);
down (&usblp->sem); mutex_lock (&usblp->mut);
usblp->sleeping = 0; usblp->sleeping = 0;
r = handle_bidir (usblp); r = handle_bidir (usblp);
up (&usblp->sem); mutex_unlock (&usblp->mut);
mutex_unlock (&usblp_mutex); mutex_unlock (&usblp_mutex);
return r; return r;
......
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