diff options
| -rw-r--r-- | drivers/media/rc/lirc_dev.c | 165 |
1 files changed, 93 insertions, 72 deletions
diff --git a/drivers/media/rc/lirc_dev.c b/drivers/media/rc/lirc_dev.c index b07d0ab..c83fffe 100644 --- a/drivers/media/rc/lirc_dev.c +++ b/drivers/media/rc/lirc_dev.c @@ -38,7 +38,7 @@ struct irctl { bool attached; int open; - struct mutex irctl_lock; + struct mutex mutex; /* protect from simultaneous accesses */ struct lirc_buffer *buf; bool buf_internal; @@ -46,6 +46,7 @@ struct irctl { struct cdev cdev; }; +/* This mutex protects the irctls array */ static DEFINE_MUTEX(lirc_dev_lock); static struct irctl *irctls[MAX_IRCTL_DEVICES]; @@ -53,20 +54,25 @@ static struct irctl *irctls[MAX_IRCTL_DEVICES]; /* Only used for sysfs but defined to void otherwise */ static struct class *lirc_class; -static void lirc_release(struct device *ld) +static void lirc_free_buffer(struct irctl *ir) { - struct irctl *ir = container_of(ld, struct irctl, dev); - put_device(ir->dev.parent); if (ir->buf_internal) { lirc_buffer_free(ir->buf); kfree(ir->buf); + ir->buf = NULL; } +} + +static void lirc_release(struct device *ld) +{ + struct irctl *ir = container_of(ld, struct irctl, dev); mutex_lock(&lirc_dev_lock); irctls[ir->d.minor] = NULL; mutex_unlock(&lirc_dev_lock); + lirc_free_buffer(ir); kfree(ir); } @@ -143,6 +149,28 @@ int lirc_register_driver(struct lirc_driver *d) return -EBADRQC; } + /* some safety check 8-) */ + d->name[sizeof(d->name) - 1] = '\0'; + + if (d->features == 0) + d->features = LIRC_CAN_REC_LIRCCODE; + + ir = kzalloc(sizeof(*ir), GFP_KERNEL); + if (!ir) + return -ENOMEM; + + mutex_init(&ir->mutex); + ir->d = *d; + + if (LIRC_CAN_REC(d->features)) { + err = lirc_allocate_buffer(ir); + if (err) { + kfree(ir); + return err; + } + d->rbuf = ir->buf; + } + mutex_lock(&lirc_dev_lock); /* find first free slot for driver */ @@ -152,37 +180,18 @@ int lirc_register_driver(struct lirc_driver *d) if (minor == MAX_IRCTL_DEVICES) { dev_err(d->dev, "no free slots for drivers!\n"); - err = -ENOMEM; - goto out_lock; - } - - ir = kzalloc(sizeof(struct irctl), GFP_KERNEL); - if (!ir) { - err = -ENOMEM; - goto out_lock; + mutex_unlock(&lirc_dev_lock); + lirc_free_buffer(ir); + kfree(ir); + return -ENOMEM; } - mutex_init(&ir->irctl_lock); irctls[minor] = ir; d->irctl = ir; d->minor = minor; + ir->d.minor = minor; - /* some safety check 8-) */ - d->name[sizeof(d->name)-1] = '\0'; - - if (d->features == 0) - d->features = LIRC_CAN_REC_LIRCCODE; - - ir->d = *d; - - if (LIRC_CAN_REC(d->features)) { - err = lirc_allocate_buffer(irctls[minor]); - if (err) { - kfree(ir); - goto out_lock; - } - d->rbuf = ir->buf; - } + mutex_unlock(&lirc_dev_lock); device_initialize(&ir->dev); ir->dev.devt = MKDEV(MAJOR(lirc_base_dev), ir->d.minor); @@ -196,10 +205,10 @@ int lirc_register_driver(struct lirc_driver *d) ir->attached = true; err = cdev_device_add(&ir->cdev, &ir->dev); - if (err) - goto out_dev; - - mutex_unlock(&lirc_dev_lock); + if (err) { + put_device(&ir->dev); + return err; + } get_device(ir->dev.parent); @@ -207,13 +216,6 @@ int lirc_register_driver(struct lirc_driver *d) ir->d.name, ir->d.minor); return 0; - -out_dev: - put_device(&ir->dev); -out_lock: - mutex_unlock(&lirc_dev_lock); - - return err; } EXPORT_SYMBOL(lirc_register_driver); @@ -226,11 +228,13 @@ void lirc_unregister_driver(struct lirc_driver *d) ir = d->irctl; - mutex_lock(&lirc_dev_lock); - dev_dbg(ir->d.dev, "lirc_dev: driver %s unregistered from minor = %d\n", d->name, d->minor); + cdev_device_del(&ir->cdev, &ir->dev); + + mutex_lock(&ir->mutex); + ir->attached = false; if (ir->open) { dev_dbg(ir->d.dev, LOGHEAD "releasing opened driver\n", @@ -238,9 +242,8 @@ void lirc_unregister_driver(struct lirc_driver *d) wake_up_interruptible(&ir->buf->wait_poll); } - mutex_unlock(&lirc_dev_lock); + mutex_unlock(&ir->mutex); - cdev_device_del(&ir->cdev, &ir->dev); put_device(&ir->dev); } EXPORT_SYMBOL(lirc_unregister_driver); @@ -252,13 +255,24 @@ int lirc_dev_fop_open(struct inode *inode, struct file *file) dev_dbg(ir->d.dev, LOGHEAD "open called\n", ir->d.name, ir->d.minor); - if (ir->open) - return -EBUSY; + retval = mutex_lock_interruptible(&ir->mutex); + if (retval) + return retval; + + if (!ir->attached) { + retval = -ENODEV; + goto out; + } + + if (ir->open) { + retval = -EBUSY; + goto out; + } if (ir->d.rdev) { retval = rc_open(ir->d.rdev); if (retval) - return retval; + goto out; } if (ir->buf) @@ -268,24 +282,26 @@ int lirc_dev_fop_open(struct inode *inode, struct file *file) lirc_init_pdata(inode, file); nonseekable_open(inode, file); + mutex_unlock(&ir->mutex); return 0; + +out: + mutex_unlock(&ir->mutex); + return retval; } EXPORT_SYMBOL(lirc_dev_fop_open); int lirc_dev_fop_close(struct inode *inode, struct file *file) { struct irctl *ir = file->private_data; - int ret; - ret = mutex_lock_killable(&lirc_dev_lock); - WARN_ON(ret); + mutex_lock(&ir->mutex); rc_close(ir->d.rdev); - ir->open--; - if (!ret) - mutex_unlock(&lirc_dev_lock); + + mutex_unlock(&ir->mutex); return 0; } @@ -320,19 +336,20 @@ long lirc_dev_fop_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { struct irctl *ir = file->private_data; __u32 mode; - int result = 0; + int result; dev_dbg(ir->d.dev, LOGHEAD "ioctl called (0x%x)\n", ir->d.name, ir->d.minor, cmd); + result = mutex_lock_interruptible(&ir->mutex); + if (result) + return result; + if (!ir->attached) { - dev_err(ir->d.dev, LOGHEAD "ioctl result = -ENODEV\n", - ir->d.name, ir->d.minor); - return -ENODEV; + result = -ENODEV; + goto out; } - mutex_lock(&ir->irctl_lock); - switch (cmd) { case LIRC_GET_FEATURES: result = put_user(ir->d.features, (__u32 __user *)arg); @@ -386,8 +403,8 @@ long lirc_dev_fop_ioctl(struct file *file, unsigned int cmd, unsigned long arg) result = -ENOTTY; } - mutex_unlock(&ir->irctl_lock); - +out: + mutex_unlock(&ir->mutex); return result; } EXPORT_SYMBOL(lirc_dev_fop_ioctl); @@ -399,27 +416,31 @@ ssize_t lirc_dev_fop_read(struct file *file, { struct irctl *ir = file->private_data; unsigned char *buf; - int ret = 0, written = 0; + int ret, written = 0; DECLARE_WAITQUEUE(wait, current); - if (!LIRC_CAN_REC(ir->d.features)) - return -EINVAL; - dev_dbg(ir->d.dev, LOGHEAD "read called\n", ir->d.name, ir->d.minor); buf = kzalloc(ir->buf->chunk_size, GFP_KERNEL); if (!buf) return -ENOMEM; - if (mutex_lock_interruptible(&ir->irctl_lock)) { - ret = -ERESTARTSYS; - goto out_unlocked; + ret = mutex_lock_interruptible(&ir->mutex); + if (ret) { + kfree(buf); + return ret; } + if (!ir->attached) { ret = -ENODEV; goto out_locked; } + if (!LIRC_CAN_REC(ir->d.features)) { + ret = -EINVAL; + goto out_locked; + } + if (length % ir->buf->chunk_size) { ret = -EINVAL; goto out_locked; @@ -454,13 +475,13 @@ ssize_t lirc_dev_fop_read(struct file *file, break; } - mutex_unlock(&ir->irctl_lock); + mutex_unlock(&ir->mutex); set_current_state(TASK_INTERRUPTIBLE); schedule(); set_current_state(TASK_RUNNING); - if (mutex_lock_interruptible(&ir->irctl_lock)) { - ret = -ERESTARTSYS; + ret = mutex_lock_interruptible(&ir->mutex); + if (ret) { remove_wait_queue(&ir->buf->wait_poll, &wait); goto out_unlocked; } @@ -483,7 +504,7 @@ ssize_t lirc_dev_fop_read(struct file *file, remove_wait_queue(&ir->buf->wait_poll, &wait); out_locked: - mutex_unlock(&ir->irctl_lock); + mutex_unlock(&ir->mutex); out_unlocked: kfree(buf); 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