diff options
Diffstat (limited to 'drivers/input/misc/uinput.c')
-rw-r--r-- | drivers/input/misc/uinput.c | 197 |
1 files changed, 123 insertions, 74 deletions
diff --git a/drivers/input/misc/uinput.c b/drivers/input/misc/uinput.c index 6b1797503e34..a0a4bbaef02c 100644 --- a/drivers/input/misc/uinput.c +++ b/drivers/input/misc/uinput.c @@ -40,7 +40,8 @@ #include <linux/input/mt.h> #include "../input-compat.h" -static int uinput_dev_event(struct input_dev *dev, unsigned int type, unsigned int code, int value) +static int uinput_dev_event(struct input_dev *dev, + unsigned int type, unsigned int code, int value) { struct uinput_device *udev = input_get_drvdata(dev); @@ -56,10 +57,11 @@ static int uinput_dev_event(struct input_dev *dev, unsigned int type, unsigned i } /* Atomically allocate an ID for the given request. Returns 0 on success. */ -static int uinput_request_alloc_id(struct uinput_device *udev, struct uinput_request *request) +static bool uinput_request_alloc_id(struct uinput_device *udev, + struct uinput_request *request) { - int id; - int err = -1; + unsigned int id; + bool reserved = false; spin_lock(&udev->requests_lock); @@ -67,32 +69,35 @@ static int uinput_request_alloc_id(struct uinput_device *udev, struct uinput_req if (!udev->requests[id]) { request->id = id; udev->requests[id] = request; - err = 0; + reserved = true; break; } } spin_unlock(&udev->requests_lock); - return err; + return reserved; } -static struct uinput_request *uinput_request_find(struct uinput_device *udev, int id) +static struct uinput_request *uinput_request_find(struct uinput_device *udev, + unsigned int id) { /* Find an input request, by ID. Returns NULL if the ID isn't valid. */ - if (id >= UINPUT_NUM_REQUESTS || id < 0) + if (id >= UINPUT_NUM_REQUESTS) return NULL; return udev->requests[id]; } -static inline int uinput_request_reserve_slot(struct uinput_device *udev, struct uinput_request *request) +static int uinput_request_reserve_slot(struct uinput_device *udev, + struct uinput_request *request) { /* Allocate slot. If none are available right away, wait. */ return wait_event_interruptible(udev->requests_waitq, - !uinput_request_alloc_id(udev, request)); + uinput_request_alloc_id(udev, request)); } -static void uinput_request_done(struct uinput_device *udev, struct uinput_request *request) +static void uinput_request_done(struct uinput_device *udev, + struct uinput_request *request) { /* Mark slot as available */ udev->requests[request->id] = NULL; @@ -101,14 +106,11 @@ static void uinput_request_done(struct uinput_device *udev, struct uinput_reques complete(&request->done); } -static int uinput_request_submit(struct uinput_device *udev, struct uinput_request *request) +static int uinput_request_send(struct uinput_device *udev, + struct uinput_request *request) { int retval; - retval = uinput_request_reserve_slot(udev, request); - if (retval) - return retval; - retval = mutex_lock_interruptible(&udev->mutex); if (retval) return retval; @@ -118,7 +120,12 @@ static int uinput_request_submit(struct uinput_device *udev, struct uinput_reque goto out; } - /* Tell our userspace app about this new request by queueing an input event */ + init_completion(&request->done); + + /* + * Tell our userspace application about this new request + * by queueing an input event. + */ uinput_dev_event(udev->dev, EV_UINPUT, request->code, request->id); out: @@ -126,8 +133,27 @@ static int uinput_request_submit(struct uinput_device *udev, struct uinput_reque return retval; } +static int uinput_request_submit(struct uinput_device *udev, + struct uinput_request *request) +{ + int error; + + error = uinput_request_reserve_slot(udev, request); + if (error) + return error; + + error = uinput_request_send(udev, request); + if (error) { + uinput_request_done(udev, request); + return error; + } + + wait_for_completion(&request->done); + return request->retval; +} + /* - * Fail all ouitstanding requests so handlers don't wait for the userspace + * Fail all outstanding requests so handlers don't wait for the userspace * to finish processing them. */ static void uinput_flush_requests(struct uinput_device *udev) @@ -163,11 +189,12 @@ static int uinput_dev_playback(struct input_dev *dev, int effect_id, int value) return uinput_dev_event(dev, EV_FF, effect_id, value); } -static int uinput_dev_upload_effect(struct input_dev *dev, struct ff_effect *effect, struct ff_effect *old) +static int uinput_dev_upload_effect(struct input_dev *dev, + struct ff_effect *effect, + struct ff_effect *old) { struct uinput_device *udev = input_get_drvdata(dev); struct uinput_request request; - int retval; /* * uinput driver does not currently support periodic effects with @@ -180,42 +207,25 @@ static int uinput_dev_upload_effect(struct input_dev *dev, struct ff_effect *eff effect->u.periodic.waveform == FF_CUSTOM) return -EINVAL; - request.id = -1; - init_completion(&request.done); request.code = UI_FF_UPLOAD; request.u.upload.effect = effect; request.u.upload.old = old; - retval = uinput_request_submit(udev, &request); - if (!retval) { - wait_for_completion(&request.done); - retval = request.retval; - } - - return retval; + return uinput_request_submit(udev, &request); } static int uinput_dev_erase_effect(struct input_dev *dev, int effect_id) { struct uinput_device *udev = input_get_drvdata(dev); struct uinput_request request; - int retval; if (!test_bit(EV_FF, dev->evbit)) return -ENOSYS; - request.id = -1; - init_completion(&request.done); request.code = UI_FF_ERASE; request.u.effect_id = effect_id; - retval = uinput_request_submit(udev, &request); - if (!retval) { - wait_for_completion(&request.done); - retval = request.retval; - } - - return retval; + return uinput_request_submit(udev, &request); } static void uinput_destroy_device(struct uinput_device *udev) @@ -347,7 +357,8 @@ static int uinput_allocate_device(struct uinput_device *udev) return 0; } -static int uinput_setup_device(struct uinput_device *udev, const char __user *buffer, size_t count) +static int uinput_setup_device(struct uinput_device *udev, + const char __user *buffer, size_t count) { struct uinput_user_dev *user_dev; struct input_dev *dev; @@ -419,7 +430,8 @@ static int uinput_setup_device(struct uinput_device *udev, const char __user *bu return retval; } -static inline ssize_t uinput_inject_event(struct uinput_device *udev, const char __user *buffer, size_t count) +static ssize_t uinput_inject_event(struct uinput_device *udev, + const char __user *buffer, size_t count) { struct input_event ev; @@ -434,11 +446,15 @@ static inline ssize_t uinput_inject_event(struct uinput_device *udev, const char return input_event_size(); } -static ssize_t uinput_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos) +static ssize_t uinput_write(struct file *file, const char __user *buffer, + size_t count, loff_t *ppos) { struct uinput_device *udev = file->private_data; int retval; + if (count == 0) + return 0; + retval = mutex_lock_interruptible(&udev->mutex); if (retval) return retval; @@ -452,42 +468,74 @@ static ssize_t uinput_write(struct file *file, const char __user *buffer, size_t return retval; } -static ssize_t uinput_read(struct file *file, char __user *buffer, size_t count, loff_t *ppos) +static bool uinput_fetch_next_event(struct uinput_device *udev, + struct input_event *event) { - struct uinput_device *udev = file->private_data; - int retval = 0; + bool have_event; - if (udev->state != UIST_CREATED) - return -ENODEV; + spin_lock_irq(&udev->dev->event_lock); - if (udev->head == udev->tail && (file->f_flags & O_NONBLOCK)) - return -EAGAIN; + have_event = udev->head != udev->tail; + if (have_event) { + *event = udev->buff[udev->tail]; + udev->tail = (udev->tail + 1) % UINPUT_BUFFER_SIZE; + } - retval = wait_event_interruptible(udev->waitq, - udev->head != udev->tail || udev->state != UIST_CREATED); - if (retval) - return retval; + spin_unlock_irq(&udev->dev->event_lock); - retval = mutex_lock_interruptible(&udev->mutex); - if (retval) - return retval; + return have_event; +} - if (udev->state != UIST_CREATED) { - retval = -ENODEV; - goto out; - } +static ssize_t uinput_events_to_user(struct uinput_device *udev, + char __user *buffer, size_t count) +{ + struct input_event event; + size_t read = 0; - while (udev->head != udev->tail && retval + input_event_size() <= count) { - if (input_event_to_user(buffer + retval, &udev->buff[udev->tail])) { - retval = -EFAULT; - goto out; - } - udev->tail = (udev->tail + 1) % UINPUT_BUFFER_SIZE; - retval += input_event_size(); + while (read + input_event_size() <= count && + uinput_fetch_next_event(udev, &event)) { + + if (input_event_to_user(buffer + read, &event)) + return -EFAULT; + + read += input_event_size(); } - out: - mutex_unlock(&udev->mutex); + return read; +} + +static ssize_t uinput_read(struct file *file, char __user *buffer, + size_t count, loff_t *ppos) +{ + struct uinput_device *udev = file->private_data; + ssize_t retval; + + if (count != 0 && count < input_event_size()) + return -EINVAL; + + do { + retval = mutex_lock_interruptible(&udev->mutex); + if (retval) + return retval; + + if (udev->state != UIST_CREATED) + retval = -ENODEV; + else if (udev->head == udev->tail && + (file->f_flags & O_NONBLOCK)) + retval = -EAGAIN; + else + retval = uinput_events_to_user(udev, buffer, count); + + mutex_unlock(&udev->mutex); + + if (retval || count == 0) + break; + + if (!(file->f_flags & O_NONBLOCK)) + retval = wait_event_interruptible(udev->waitq, + udev->head != udev->tail || + udev->state != UIST_CREATED); + } while (retval == 0); return retval; } @@ -516,8 +564,8 @@ static int uinput_release(struct inode *inode, struct file *file) #ifdef CONFIG_COMPAT struct uinput_ff_upload_compat { - int request_id; - int retval; + __u32 request_id; + __s32 retval; struct ff_effect_compat effect; struct ff_effect_compat old; }; @@ -703,7 +751,8 @@ static long uinput_ioctl_handler(struct file *file, unsigned int cmd, break; req = uinput_request_find(udev, ff_up.request_id); - if (!req || req->code != UI_FF_UPLOAD || !req->u.upload.effect) { + if (!req || req->code != UI_FF_UPLOAD || + !req->u.upload.effect) { retval = -EINVAL; break; } @@ -786,7 +835,8 @@ static long uinput_ioctl(struct file *file, unsigned int cmd, unsigned long arg) } #ifdef CONFIG_COMPAT -static long uinput_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg) +static long uinput_compat_ioctl(struct file *file, + unsigned int cmd, unsigned long arg) { return uinput_ioctl_handler(file, cmd, arg, compat_ptr(arg)); } @@ -831,4 +881,3 @@ MODULE_VERSION("0.3"); module_init(uinput_init); module_exit(uinput_exit); - |