USB: gadget/printer, fix sleep inside atomic
Stanse found that sleep is called inside atomic context created by
lock_printer_io spinlock in several functions. It's used in process
context only and some functions sleep inside its critical section. As
this is not allowed for spinlocks, switch it to mutex.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Craig W. Nadler <craig@nadler.us>
Acked-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/usb/gadget/printer.c b/drivers/usb/gadget/printer.c
index 43abf55..4c3ac5c 100644
--- a/drivers/usb/gadget/printer.c
+++ b/drivers/usb/gadget/printer.c
@@ -82,7 +82,7 @@
struct printer_dev {
spinlock_t lock; /* lock this structure */
/* lock buffer lists during read/write calls */
- spinlock_t lock_printer_io;
+ struct mutex lock_printer_io;
struct usb_gadget *gadget;
struct usb_request *req; /* for control responses */
u8 config;
@@ -567,7 +567,7 @@
DBG(dev, "printer_read trying to read %d bytes\n", (int)len);
- spin_lock(&dev->lock_printer_io);
+ mutex_lock(&dev->lock_printer_io);
spin_lock_irqsave(&dev->lock, flags);
/* We will use this flag later to check if a printer reset happened
@@ -601,7 +601,7 @@
* call or not.
*/
if (fd->f_flags & (O_NONBLOCK|O_NDELAY)) {
- spin_unlock(&dev->lock_printer_io);
+ mutex_unlock(&dev->lock_printer_io);
return -EAGAIN;
}
@@ -648,7 +648,7 @@
if (dev->reset_printer) {
list_add(¤t_rx_req->list, &dev->rx_reqs);
spin_unlock_irqrestore(&dev->lock, flags);
- spin_unlock(&dev->lock_printer_io);
+ mutex_unlock(&dev->lock_printer_io);
return -EAGAIN;
}
@@ -673,7 +673,7 @@
dev->current_rx_buf = current_rx_buf;
spin_unlock_irqrestore(&dev->lock, flags);
- spin_unlock(&dev->lock_printer_io);
+ mutex_unlock(&dev->lock_printer_io);
DBG(dev, "printer_read returned %d bytes\n", (int)bytes_copied);
@@ -697,7 +697,7 @@
if (len == 0)
return -EINVAL;
- spin_lock(&dev->lock_printer_io);
+ mutex_lock(&dev->lock_printer_io);
spin_lock_irqsave(&dev->lock, flags);
/* Check if a printer reset happens while we have interrupts on */
@@ -713,7 +713,7 @@
* a NON-Blocking call or not.
*/
if (fd->f_flags & (O_NONBLOCK|O_NDELAY)) {
- spin_unlock(&dev->lock_printer_io);
+ mutex_unlock(&dev->lock_printer_io);
return -EAGAIN;
}
@@ -752,7 +752,7 @@
if (copy_from_user(req->buf, buf, size)) {
list_add(&req->list, &dev->tx_reqs);
- spin_unlock(&dev->lock_printer_io);
+ mutex_unlock(&dev->lock_printer_io);
return bytes_copied;
}
@@ -766,14 +766,14 @@
if (dev->reset_printer) {
list_add(&req->list, &dev->tx_reqs);
spin_unlock_irqrestore(&dev->lock, flags);
- spin_unlock(&dev->lock_printer_io);
+ mutex_unlock(&dev->lock_printer_io);
return -EAGAIN;
}
if (usb_ep_queue(dev->in_ep, req, GFP_ATOMIC)) {
list_add(&req->list, &dev->tx_reqs);
spin_unlock_irqrestore(&dev->lock, flags);
- spin_unlock(&dev->lock_printer_io);
+ mutex_unlock(&dev->lock_printer_io);
return -EAGAIN;
}
@@ -782,7 +782,7 @@
}
spin_unlock_irqrestore(&dev->lock, flags);
- spin_unlock(&dev->lock_printer_io);
+ mutex_unlock(&dev->lock_printer_io);
DBG(dev, "printer_write sent %d bytes\n", (int)bytes_copied);
@@ -820,11 +820,11 @@
unsigned long flags;
int status = 0;
- spin_lock(&dev->lock_printer_io);
+ mutex_lock(&dev->lock_printer_io);
spin_lock_irqsave(&dev->lock, flags);
setup_rx_reqs(dev);
spin_unlock_irqrestore(&dev->lock, flags);
- spin_unlock(&dev->lock_printer_io);
+ mutex_unlock(&dev->lock_printer_io);
poll_wait(fd, &dev->rx_wait, wait);
poll_wait(fd, &dev->tx_wait, wait);
@@ -1461,7 +1461,7 @@
}
spin_lock_init(&dev->lock);
- spin_lock_init(&dev->lock_printer_io);
+ mutex_init(&dev->lock_printer_io);
INIT_LIST_HEAD(&dev->tx_reqs);
INIT_LIST_HEAD(&dev->tx_reqs_active);
INIT_LIST_HEAD(&dev->rx_reqs);
@@ -1594,7 +1594,7 @@
{
int status;
- spin_lock(&usb_printer_gadget.lock_printer_io);
+ mutex_lock(&usb_printer_gadget.lock_printer_io);
class_destroy(usb_gadget_class);
unregister_chrdev_region(g_printer_devno, 2);
@@ -1602,6 +1602,6 @@
if (status)
ERROR(dev, "usb_gadget_unregister_driver %x\n", status);
- spin_unlock(&usb_printer_gadget.lock_printer_io);
+ mutex_unlock(&usb_printer_gadget.lock_printer_io);
}
module_exit(cleanup);