From 925ce689bb31960c839804c19ef38d676f1939b9 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Sun, 11 Jul 2010 23:18:56 +0200 Subject: [PATCH] USB: autoconvert trivial BKL users to private mutex All these files use the big kernel lock in a trivial way to serialize their private file operations, typically resulting from an earlier semi-automatic pushdown from VFS. None of these drivers appears to want to lock against other code, and they all use the BKL as the top-level lock in their file operations, meaning that there is no lock-order inversion problem. Consequently, we can remove the BKL completely, replacing it with a per-file mutex in every case. Using a scripted approach means we can avoid typos. file=$1 name=$2 if grep -q lock_kernel ${file} ; then if grep -q 'include.*linux.mutex.h' ${file} ; then sed -i '/include.*/d' ${file} else sed -i 's/include.*.*$/include /g' ${file} fi sed -i ${file} \ -e "/^#include.*linux.mutex.h/,$ { 1,/^\(static\|int\|long\)/ { /^\(static\|int\|long\)/istatic DEFINE_MUTEX(${name}_mutex); } }" \ -e "s/\(un\)*lock_kernel\>[ ]*()/mutex_\1lock(\&${name}_mutex)/g" \ -e '/[ ]*cycle_kernel_lock();/d' else sed -i -e '/include.*\/d' ${file} \ -e '/cycle_kernel_lock()/d' fi Signed-off-by: Arnd Bergmann Signed-off-by: Greg Kroah-Hartman --- drivers/usb/gadget/printer.c | 7 ++++--- drivers/usb/misc/iowarrior.c | 15 ++++++++------- drivers/usb/misc/rio500.c | 15 ++++++++------- drivers/usb/misc/usblcd.c | 16 ++++++++-------- 4 files changed, 28 insertions(+), 25 deletions(-) diff --git a/drivers/usb/gadget/printer.c b/drivers/usb/gadget/printer.c index 88f05996aa0..cf241c371a7 100644 --- a/drivers/usb/gadget/printer.c +++ b/drivers/usb/gadget/printer.c @@ -25,7 +25,7 @@ #include #include #include -#include +#include #include #include #include @@ -70,6 +70,7 @@ #define DRIVER_DESC "Printer Gadget" #define DRIVER_VERSION "2007 OCT 06" +static DEFINE_MUTEX(printer_mutex); static const char shortname [] = "printer"; static const char driver_desc [] = DRIVER_DESC; @@ -476,7 +477,7 @@ printer_open(struct inode *inode, struct file *fd) unsigned long flags; int ret = -EBUSY; - lock_kernel(); + mutex_lock(&printer_mutex); dev = container_of(inode->i_cdev, struct printer_dev, printer_cdev); spin_lock_irqsave(&dev->lock, flags); @@ -492,7 +493,7 @@ printer_open(struct inode *inode, struct file *fd) spin_unlock_irqrestore(&dev->lock, flags); DBG(dev, "printer_open returned %x\n", ret); - unlock_kernel(); + mutex_unlock(&printer_mutex); return ret; } diff --git a/drivers/usb/misc/iowarrior.c b/drivers/usb/misc/iowarrior.c index 7dc9d3c6998..82966458a00 100644 --- a/drivers/usb/misc/iowarrior.c +++ b/drivers/usb/misc/iowarrior.c @@ -18,7 +18,7 @@ #include #include #include -#include +#include #include #include @@ -61,6 +61,7 @@ MODULE_DESCRIPTION(DRIVER_DESC); MODULE_LICENSE("GPL"); /* Module parameters */ +static DEFINE_MUTEX(iowarrior_mutex); static int debug = 0; module_param(debug, bool, 0644); MODULE_PARM_DESC(debug, "debug=1 enables debugging messages"); @@ -493,7 +494,7 @@ static long iowarrior_ioctl(struct file *file, unsigned int cmd, return -ENOMEM; /* lock this object */ - lock_kernel(); + mutex_lock(&iowarrior_mutex); mutex_lock(&dev->mutex); /* verify that the device wasn't unplugged */ @@ -585,7 +586,7 @@ static long iowarrior_ioctl(struct file *file, unsigned int cmd, error_out: /* unlock the device */ mutex_unlock(&dev->mutex); - unlock_kernel(); + mutex_unlock(&iowarrior_mutex); kfree(buffer); return retval; } @@ -602,12 +603,12 @@ static int iowarrior_open(struct inode *inode, struct file *file) dbg("%s", __func__); - lock_kernel(); + mutex_lock(&iowarrior_mutex); subminor = iminor(inode); interface = usb_find_interface(&iowarrior_driver, subminor); if (!interface) { - unlock_kernel(); + mutex_unlock(&iowarrior_mutex); err("%s - error, can't find device for minor %d", __func__, subminor); return -ENODEV; @@ -617,7 +618,7 @@ static int iowarrior_open(struct inode *inode, struct file *file) dev = usb_get_intfdata(interface); if (!dev) { mutex_unlock(&iowarrior_open_disc_lock); - unlock_kernel(); + mutex_unlock(&iowarrior_mutex); return -ENODEV; } @@ -644,7 +645,7 @@ static int iowarrior_open(struct inode *inode, struct file *file) out: mutex_unlock(&dev->mutex); - unlock_kernel(); + mutex_unlock(&iowarrior_mutex); return retval; } diff --git a/drivers/usb/misc/rio500.c b/drivers/usb/misc/rio500.c index a85771b1563..cc13ae61712 100644 --- a/drivers/usb/misc/rio500.c +++ b/drivers/usb/misc/rio500.c @@ -32,7 +32,7 @@ #include #include #include -#include +#include #include #include #include @@ -72,6 +72,7 @@ struct rio_usb_data { struct mutex lock; /* general race avoidance */ }; +static DEFINE_MUTEX(rio500_mutex); static struct rio_usb_data rio_instance; static int open_rio(struct inode *inode, struct file *file) @@ -79,12 +80,12 @@ static int open_rio(struct inode *inode, struct file *file) struct rio_usb_data *rio = &rio_instance; /* against disconnect() */ - lock_kernel(); + mutex_lock(&rio500_mutex); mutex_lock(&(rio->lock)); if (rio->isopen || !rio->present) { mutex_unlock(&(rio->lock)); - unlock_kernel(); + mutex_unlock(&rio500_mutex); return -EBUSY; } rio->isopen = 1; @@ -94,7 +95,7 @@ static int open_rio(struct inode *inode, struct file *file) mutex_unlock(&(rio->lock)); dev_info(&rio->rio_dev->dev, "Rio opened.\n"); - unlock_kernel(); + mutex_unlock(&rio500_mutex); return 0; } @@ -491,7 +492,7 @@ static void disconnect_rio(struct usb_interface *intf) struct rio_usb_data *rio = usb_get_intfdata (intf); usb_set_intfdata (intf, NULL); - lock_kernel(); + mutex_lock(&rio500_mutex); if (rio) { usb_deregister_dev(intf, &usb_rio_class); @@ -501,7 +502,7 @@ static void disconnect_rio(struct usb_interface *intf) /* better let it finish - the release will do whats needed */ rio->rio_dev = NULL; mutex_unlock(&(rio->lock)); - unlock_kernel(); + mutex_unlock(&rio500_mutex); return; } kfree(rio->ibuf); @@ -512,7 +513,7 @@ static void disconnect_rio(struct usb_interface *intf) rio->present = 0; mutex_unlock(&(rio->lock)); } - unlock_kernel(); + mutex_unlock(&rio500_mutex); } static const struct usb_device_id rio_table[] = { diff --git a/drivers/usb/misc/usblcd.c b/drivers/usb/misc/usblcd.c index 7828c764b32..6ae39e3e504 100644 --- a/drivers/usb/misc/usblcd.c +++ b/drivers/usb/misc/usblcd.c @@ -16,7 +16,6 @@ #include #include #include -#include #include #include #include @@ -30,6 +29,7 @@ #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, }, { }, @@ -74,12 +74,12 @@ static int lcd_open(struct inode *inode, struct file *file) struct usb_interface *interface; int subminor, r; - lock_kernel(); + mutex_lock(&lcd_mutex); subminor = iminor(inode); interface = usb_find_interface(&lcd_driver, subminor); if (!interface) { - unlock_kernel(); + mutex_unlock(&lcd_mutex); err ("USBLCD: %s - error, can't find device for minor %d", __func__, subminor); return -ENODEV; @@ -89,7 +89,7 @@ static int lcd_open(struct inode *inode, struct file *file) dev = usb_get_intfdata(interface); if (!dev) { mutex_unlock(&open_disc_mutex); - unlock_kernel(); + mutex_unlock(&lcd_mutex); return -ENODEV; } @@ -101,13 +101,13 @@ static int lcd_open(struct inode *inode, struct file *file) r = usb_autopm_get_interface(interface); if (r < 0) { kref_put(&dev->kref, lcd_delete); - unlock_kernel(); + mutex_unlock(&lcd_mutex); return r; } /* save our object in the file's private structure */ file->private_data = dev; - unlock_kernel(); + mutex_unlock(&lcd_mutex); return 0; } @@ -164,14 +164,14 @@ static long lcd_ioctl(struct file *file, unsigned int cmd, unsigned long arg) switch (cmd) { case IOCTL_GET_HARD_VERSION: - lock_kernel(); + 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)); - unlock_kernel(); + mutex_unlock(&lcd_mutex); if (copy_to_user((void __user *)arg,buf,strlen(buf))!=0) return -EFAULT; break; -- 2.39.3