Update Linux to v5.4.2
Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/drivers/usb/misc/usblcd.c b/drivers/usb/misc/usblcd.c
index 9ba4a4e..61e9e98 100644
--- a/drivers/usb/misc/usblcd.c
+++ b/drivers/usb/misc/usblcd.c
@@ -18,6 +18,7 @@
#include <linux/slab.h>
#include <linux/errno.h>
#include <linux/mutex.h>
+#include <linux/rwsem.h>
#include <linux/uaccess.h>
#include <linux/usb.h>
@@ -29,16 +30,12 @@
#define IOCTL_GET_DRV_VERSION 2
-static DEFINE_MUTEX(lcd_mutex);
static const struct usb_device_id id_table[] = {
{ .idVendor = 0x10D2, .match_flags = USB_DEVICE_ID_MATCH_VENDOR, },
{ },
};
MODULE_DEVICE_TABLE(usb, id_table);
-static DEFINE_MUTEX(open_disc_mutex);
-
-
struct usb_lcd {
struct usb_device *udev; /* init: probe_lcd */
struct usb_interface *interface; /* the interface for
@@ -57,6 +54,8 @@
using up all RAM */
struct usb_anchor submitted; /* URBs to wait for
before suspend */
+ struct rw_semaphore io_rwsem;
+ unsigned long disconnected:1;
};
#define to_lcd_dev(d) container_of(d, struct usb_lcd, kref)
@@ -81,40 +80,29 @@
struct usb_interface *interface;
int subminor, r;
- mutex_lock(&lcd_mutex);
subminor = iminor(inode);
interface = usb_find_interface(&lcd_driver, subminor);
if (!interface) {
- mutex_unlock(&lcd_mutex);
- printk(KERN_ERR "USBLCD: %s - error, can't find device for minor %d\n",
+ pr_err("USBLCD: %s - error, can't find device for minor %d\n",
__func__, subminor);
return -ENODEV;
}
- mutex_lock(&open_disc_mutex);
dev = usb_get_intfdata(interface);
- if (!dev) {
- mutex_unlock(&open_disc_mutex);
- mutex_unlock(&lcd_mutex);
- return -ENODEV;
- }
/* increment our usage count for the device */
kref_get(&dev->kref);
- mutex_unlock(&open_disc_mutex);
/* grab a power reference */
r = usb_autopm_get_interface(interface);
if (r < 0) {
kref_put(&dev->kref, lcd_delete);
- mutex_unlock(&lcd_mutex);
return r;
}
/* save our object in the file's private structure */
file->private_data = dev;
- mutex_unlock(&lcd_mutex);
return 0;
}
@@ -142,6 +130,13 @@
dev = file->private_data;
+ down_read(&dev->io_rwsem);
+
+ if (dev->disconnected) {
+ retval = -ENODEV;
+ goto out_up_io;
+ }
+
/* do a blocking bulk read to get data from the device */
retval = usb_bulk_msg(dev->udev,
usb_rcvbulkpipe(dev->udev,
@@ -158,6 +153,9 @@
retval = bytes_read;
}
+out_up_io:
+ up_read(&dev->io_rwsem);
+
return retval;
}
@@ -173,14 +171,12 @@
switch (cmd) {
case IOCTL_GET_HARD_VERSION:
- mutex_lock(&lcd_mutex);
bcdDevice = le16_to_cpu((dev->udev)->descriptor.bcdDevice);
sprintf(buf, "%1d%1d.%1d%1d",
(bcdDevice & 0xF000)>>12,
(bcdDevice & 0xF00)>>8,
(bcdDevice & 0xF0)>>4,
(bcdDevice & 0xF));
- mutex_unlock(&lcd_mutex);
if (copy_to_user((void __user *)arg, buf, strlen(buf)) != 0)
return -EFAULT;
break;
@@ -237,11 +233,18 @@
if (r < 0)
return -EINTR;
+ down_read(&dev->io_rwsem);
+
+ if (dev->disconnected) {
+ retval = -ENODEV;
+ goto err_up_io;
+ }
+
/* create a urb, and a buffer for it, and copy the data to the urb */
urb = usb_alloc_urb(0, GFP_KERNEL);
if (!urb) {
retval = -ENOMEM;
- goto err_no_buf;
+ goto err_up_io;
}
buf = usb_alloc_coherent(dev->udev, count, GFP_KERNEL,
@@ -278,6 +281,7 @@
the USB core will eventually free it entirely */
usb_free_urb(urb);
+ up_read(&dev->io_rwsem);
exit:
return count;
error_unanchor:
@@ -285,7 +289,8 @@
error:
usb_free_coherent(dev->udev, count, buf, urb->transfer_dma);
usb_free_urb(urb);
-err_no_buf:
+err_up_io:
+ up_read(&dev->io_rwsem);
up(&dev->limit_sem);
return retval;
}
@@ -325,6 +330,7 @@
kref_init(&dev->kref);
sema_init(&dev->limit_sem, USB_LCD_CONCURRENT_WRITES);
+ init_rwsem(&dev->io_rwsem);
init_usb_anchor(&dev->submitted);
dev->udev = usb_get_dev(interface_to_usbdev(interface));
@@ -365,7 +371,6 @@
/* something prevented us from registering this driver */
dev_err(&interface->dev,
"Not able to get a minor for this device.\n");
- usb_set_intfdata(interface, NULL);
goto error;
}
@@ -411,17 +416,18 @@
static void lcd_disconnect(struct usb_interface *interface)
{
- struct usb_lcd *dev;
+ struct usb_lcd *dev = usb_get_intfdata(interface);
int minor = interface->minor;
- mutex_lock(&open_disc_mutex);
- dev = usb_get_intfdata(interface);
- usb_set_intfdata(interface, NULL);
- mutex_unlock(&open_disc_mutex);
-
/* give back our minor */
usb_deregister_dev(interface, &lcd_class);
+ down_write(&dev->io_rwsem);
+ dev->disconnected = 1;
+ up_write(&dev->io_rwsem);
+
+ usb_kill_anchored_urbs(&dev->submitted);
+
/* decrement our usage count */
kref_put(&dev->kref, lcd_delete);