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Diffstat (limited to 'drivers/input/misc/uinput.c')
-rw-r--r--drivers/input/misc/uinput.c197
1 files changed, 123 insertions, 74 deletions
diff --git a/drivers/input/misc/uinput.c b/drivers/input/misc/uinput.c
index 736056897e50..86328e9c9848 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);
-