| /* |
| * Event char devices, giving access to raw input device events. |
| * |
| * Copyright (c) 1999-2002 Vojtech Pavlik |
| * |
| * This program is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 as published by |
| * the Free Software Foundation. |
| */ |
| |
| #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
| |
| #define EVDEV_MINOR_BASE 64 |
| #define EVDEV_MINORS 32 |
| #define EVDEV_MIN_BUFFER_SIZE 64U |
| #define EVDEV_BUF_PACKETS 8 |
| |
| #include <linux/poll.h> |
| #include <linux/sched.h> |
| #include <linux/slab.h> |
| #include <linux/module.h> |
| #include <linux/init.h> |
| #include <linux/input.h> |
| #include <linux/major.h> |
| #include <linux/device.h> |
| #include <linux/wakelock.h> |
| #include "input-compat.h" |
| |
| struct evdev { |
| int open; |
| int minor; |
| struct input_handle handle; |
| wait_queue_head_t wait; |
| struct evdev_client __rcu *grab; |
| struct list_head client_list; |
| spinlock_t client_lock; /* protects client_list */ |
| struct mutex mutex; |
| struct device dev; |
| bool exist; |
| }; |
| |
| struct evdev_client { |
| unsigned int head; |
| unsigned int tail; |
| unsigned int packet_head; /* [future] position of the first element of next packet */ |
| spinlock_t buffer_lock; /* protects access to buffer, head and tail */ |
| struct wake_lock wake_lock; |
| char name[28]; |
| struct fasync_struct *fasync; |
| struct evdev *evdev; |
| struct list_head node; |
| unsigned int bufsize; |
| struct input_event buffer[]; |
| }; |
| |
| static struct evdev *evdev_table[EVDEV_MINORS]; |
| static DEFINE_MUTEX(evdev_table_mutex); |
| |
| static void evdev_pass_event(struct evdev_client *client, |
| struct input_event *event) |
| { |
| /* Interrupts are disabled, just acquire the lock. */ |
| spin_lock(&client->buffer_lock); |
| |
| wake_lock_timeout(&client->wake_lock, 5 * HZ); |
| client->buffer[client->head++] = *event; |
| client->head &= client->bufsize - 1; |
| |
| if (unlikely(client->head == client->tail)) { |
| /* |
| * This effectively "drops" all unconsumed events, leaving |
| * EV_SYN/SYN_DROPPED plus the newest event in the queue. |
| */ |
| client->tail = (client->head - 2) & (client->bufsize - 1); |
| |
| client->buffer[client->tail].time = event->time; |
| client->buffer[client->tail].type = EV_SYN; |
| client->buffer[client->tail].code = SYN_DROPPED; |
| client->buffer[client->tail].value = 0; |
| |
| client->packet_head = client->tail; |
| } |
| |
| if (event->type == EV_SYN && event->code == SYN_REPORT) { |
| client->packet_head = client->head; |
| kill_fasync(&client->fasync, SIGIO, POLL_IN); |
| } |
| |
| spin_unlock(&client->buffer_lock); |
| } |
| |
| /* |
| * Pass incoming event to all connected clients. |
| */ |
| static void evdev_event(struct input_handle *handle, |
| unsigned int type, unsigned int code, int value) |
| { |
| struct evdev *evdev = handle->private; |
| struct evdev_client *client; |
| struct input_event event; |
| struct timespec ts; |
| |
| ktime_get_ts(&ts); |
| event.time.tv_sec = ts.tv_sec; |
| event.time.tv_usec = ts.tv_nsec / NSEC_PER_USEC; |
| event.type = type; |
| event.code = code; |
| event.value = value; |
| |
| rcu_read_lock(); |
| |
| client = rcu_dereference(evdev->grab); |
| if (client) |
| evdev_pass_event(client, &event); |
| else |
| list_for_each_entry_rcu(client, &evdev->client_list, node) |
| evdev_pass_event(client, &event); |
| |
| rcu_read_unlock(); |
| |
| if (type == EV_SYN && code == SYN_REPORT) |
| wake_up_interruptible(&evdev->wait); |
| } |
| |
| static int evdev_fasync(int fd, struct file *file, int on) |
| { |
| struct evdev_client *client = file->private_data; |
| |
| return fasync_helper(fd, file, on, &client->fasync); |
| } |
| |
| static int evdev_flush(struct file *file, fl_owner_t id) |
| { |
| struct evdev_client *client = file->private_data; |
| struct evdev *evdev = client->evdev; |
| int retval; |
| |
| retval = mutex_lock_interruptible(&evdev->mutex); |
| if (retval) |
| return retval; |
| |
| if (!evdev->exist) |
| retval = -ENODEV; |
| else |
| retval = input_flush_device(&evdev->handle, file); |
| |
| mutex_unlock(&evdev->mutex); |
| return retval; |
| } |
| |
| static void evdev_free(struct device *dev) |
| { |
| struct evdev *evdev = container_of(dev, struct evdev, dev); |
| |
| input_put_device(evdev->handle.dev); |
| kfree(evdev); |
| } |
| |
| /* |
| * Grabs an event device (along with underlying input device). |
| * This function is called with evdev->mutex taken. |
| */ |
| static int evdev_grab(struct evdev *evdev, struct evdev_client *client) |
| { |
| int error; |
| |
| if (evdev->grab) |
| return -EBUSY; |
| |
| error = input_grab_device(&evdev->handle); |
| if (error) |
| return error; |
| |
| rcu_assign_pointer(evdev->grab, client); |
| |
| return 0; |
| } |
| |
| static int evdev_ungrab(struct evdev *evdev, struct evdev_client *client) |
| { |
| if (evdev->grab != client) |
| return -EINVAL; |
| |
| rcu_assign_pointer(evdev->grab, NULL); |
| synchronize_rcu(); |
| input_release_device(&evdev->handle); |
| |
| return 0; |
| } |
| |
| static void evdev_attach_client(struct evdev *evdev, |
| struct evdev_client *client) |
| { |
| spin_lock(&evdev->client_lock); |
| list_add_tail_rcu(&client->node, &evdev->client_list); |
| spin_unlock(&evdev->client_lock); |
| } |
| |
| static void evdev_detach_client(struct evdev *evdev, |
| struct evdev_client *client) |
| { |
| spin_lock(&evdev->client_lock); |
| list_del_rcu(&client->node); |
| spin_unlock(&evdev->client_lock); |
| synchronize_rcu(); |
| } |
| |
| static int evdev_open_device(struct evdev *evdev) |
| { |
| int retval; |
| |
| retval = mutex_lock_interruptible(&evdev->mutex); |
| if (retval) |
| return retval; |
| |
| if (!evdev->exist) |
| retval = -ENODEV; |
| else if (!evdev->open++) { |
| retval = input_open_device(&evdev->handle); |
| if (retval) |
| evdev->open--; |
| } |
| |
| mutex_unlock(&evdev->mutex); |
| return retval; |
| } |
| |
| static void evdev_close_device(struct evdev *evdev) |
| { |
| mutex_lock(&evdev->mutex); |
| |
| if (evdev->exist && !--evdev->open) |
| input_close_device(&evdev->handle); |
| |
| mutex_unlock(&evdev->mutex); |
| } |
| |
| /* |
| * Wake up users waiting for IO so they can disconnect from |
| * dead device. |
| */ |
| static void evdev_hangup(struct evdev *evdev) |
| { |
| struct evdev_client *client; |
| |
| spin_lock(&evdev->client_lock); |
| list_for_each_entry(client, &evdev->client_list, node) |
| kill_fasync(&client->fasync, SIGIO, POLL_HUP); |
| spin_unlock(&evdev->client_lock); |
| |
| wake_up_interruptible(&evdev->wait); |
| } |
| |
| static int evdev_release(struct inode *inode, struct file *file) |
| { |
| struct evdev_client *client = file->private_data; |
| struct evdev *evdev = client->evdev; |
| |
| mutex_lock(&evdev->mutex); |
| if (evdev->grab == client) |
| evdev_ungrab(evdev, client); |
| mutex_unlock(&evdev->mutex); |
| |
| evdev_detach_client(evdev, client); |
| wake_lock_destroy(&client->wake_lock); |
| kfree(client); |
| |
| evdev_close_device(evdev); |
| put_device(&evdev->dev); |
| |
| return 0; |
| } |
| |
| static unsigned int evdev_compute_buffer_size(struct input_dev *dev) |
| { |
| unsigned int n_events = |
| max(dev->hint_events_per_packet * EVDEV_BUF_PACKETS, |
| EVDEV_MIN_BUFFER_SIZE); |
| |
| return roundup_pow_of_two(n_events); |
| } |
| |
| static int evdev_open(struct inode *inode, struct file *file) |
| { |
| struct evdev *evdev; |
| struct evdev_client *client; |
| int i = iminor(inode) - EVDEV_MINOR_BASE; |
| unsigned int bufsize; |
| int error; |
| |
| if (i >= EVDEV_MINORS) |
| return -ENODEV; |
| |
| error = mutex_lock_interruptible(&evdev_table_mutex); |
| if (error) |
| return error; |
| evdev = evdev_table[i]; |
| if (evdev) |
| get_device(&evdev->dev); |
| mutex_unlock(&evdev_table_mutex); |
| |
| if (!evdev) |
| return -ENODEV; |
| |
| bufsize = evdev_compute_buffer_size(evdev->handle.dev); |
| |
| client = kzalloc(sizeof(struct evdev_client) + |
| bufsize * sizeof(struct input_event), |
| GFP_KERNEL); |
| if (!client) { |
| error = -ENOMEM; |
| goto err_put_evdev; |
| } |
| |
| client->bufsize = bufsize; |
| spin_lock_init(&client->buffer_lock); |
| snprintf(client->name, sizeof(client->name), "%s-%d", |
| dev_name(&evdev->dev), task_tgid_vnr(current)); |
| wake_lock_init(&client->wake_lock, WAKE_LOCK_SUSPEND, client->name); |
| client->evdev = evdev; |
| evdev_attach_client(evdev, client); |
| |
| error = evdev_open_device(evdev); |
| if (error) |
| goto err_free_client; |
| |
| file->private_data = client; |
| nonseekable_open(inode, file); |
| |
| return 0; |
| |
| err_free_client: |
| evdev_detach_client(evdev, client); |
| wake_lock_destroy(&client->wake_lock); |
| kfree(client); |
| err_put_evdev: |
| put_device(&evdev->dev); |
| return error; |
| } |
| |
| static ssize_t evdev_write(struct file *file, const char __user *buffer, |
| size_t count, loff_t *ppos) |
| { |
| struct evdev_client *client = file->private_data; |
| struct evdev *evdev = client->evdev; |
| struct input_event event; |
| int retval; |
| |
| if (count < input_event_size()) |
| return -EINVAL; |
| |
| retval = mutex_lock_interruptible(&evdev->mutex); |
| if (retval) |
| return retval; |
| |
| if (!evdev->exist) { |
| retval = -ENODEV; |
| goto out; |
| } |
| |
| do { |
| if (input_event_from_user(buffer + retval, &event)) { |
| retval = -EFAULT; |
| goto out; |
| } |
| retval += input_event_size(); |
| |
| input_inject_event(&evdev->handle, |
| event.type, event.code, event.value); |
| } while (retval + input_event_size() <= count); |
| |
| out: |
| mutex_unlock(&evdev->mutex); |
| return retval; |
| } |
| |
| static int evdev_fetch_next_event(struct evdev_client *client, |
| struct input_event *event) |
| { |
| int have_event; |
| |
| spin_lock_irq(&client->buffer_lock); |
| |
| have_event = client->packet_head != client->tail; |
| if (have_event) { |
| *event = client->buffer[client->tail++]; |
| client->tail &= client->bufsize - 1; |
| if (client->head == client->tail) |
| wake_unlock(&client->wake_lock); |
| } |
| |
| spin_unlock_irq(&client->buffer_lock); |
| |
| return have_event; |
| } |
| |
| static ssize_t evdev_read(struct file *file, char __user *buffer, |
| size_t count, loff_t *ppos) |
| { |
| struct evdev_client *client = file->private_data; |
| struct evdev *evdev = client->evdev; |
| struct input_event event; |
| int retval = 0; |
| |
| if (count < input_event_size()) |
| return -EINVAL; |
| |
| if (!(file->f_flags & O_NONBLOCK)) { |
| retval = wait_event_interruptible(evdev->wait, |
| client->packet_head != client->tail || !evdev->exist); |
| if (retval) |
| return retval; |
| } |
| |
| if (!evdev->exist) |
| return -ENODEV; |
| |
| while (retval + input_event_size() <= count && |
| evdev_fetch_next_event(client, &event)) { |
| |
| if (input_event_to_user(buffer + retval, &event)) |
| return -EFAULT; |
| |
| retval += input_event_size(); |
| } |
| |
| if (retval == 0 && file->f_flags & O_NONBLOCK) |
| retval = -EAGAIN; |
| return retval; |
| } |
| |
| /* No kernel lock - fine */ |
| static unsigned int evdev_poll(struct file *file, poll_table *wait) |
| { |
| struct evdev_client *client = file->private_data; |
| struct evdev *evdev = client->evdev; |
| unsigned int mask; |
| |
| poll_wait(file, &evdev->wait, wait); |
| |
| mask = evdev->exist ? POLLOUT | POLLWRNORM : POLLHUP | POLLERR; |
| if (client->packet_head != client->tail) |
| mask |= POLLIN | POLLRDNORM; |
| |
| return mask; |
| } |
| |
| #ifdef CONFIG_COMPAT |
| |
| #define BITS_PER_LONG_COMPAT (sizeof(compat_long_t) * 8) |
| #define BITS_TO_LONGS_COMPAT(x) ((((x) - 1) / BITS_PER_LONG_COMPAT) + 1) |
| |
| #ifdef __BIG_ENDIAN |
| static int bits_to_user(unsigned long *bits, unsigned int maxbit, |
| unsigned int maxlen, void __user *p, int compat) |
| { |
| int len, i; |
| |
| if (compat) { |
| len = BITS_TO_LONGS_COMPAT(maxbit) * sizeof(compat_long_t); |
| if (len > maxlen) |
| len = maxlen; |
| |
| for (i = 0; i < len / sizeof(compat_long_t); i++) |
| if (copy_to_user((compat_long_t __user *) p + i, |
| (compat_long_t *) bits + |
| i + 1 - ((i % 2) << 1), |
| sizeof(compat_long_t))) |
| return -EFAULT; |
| } else { |
| len = BITS_TO_LONGS(maxbit) * sizeof(long); |
| if (len > maxlen) |
| len = maxlen; |
| |
| if (copy_to_user(p, bits, len)) |
| return -EFAULT; |
| } |
| |
| return len; |
| } |
| #else |
| static int bits_to_user(unsigned long *bits, unsigned int maxbit, |
| unsigned int maxlen, void __user *p, int compat) |
| { |
| int len = compat ? |
| BITS_TO_LONGS_COMPAT(maxbit) * sizeof(compat_long_t) : |
| BITS_TO_LONGS(maxbit) * sizeof(long); |
| |
| if (len > maxlen) |
| len = maxlen; |
| |
| return copy_to_user(p, bits, len) ? -EFAULT : len; |
| } |
| #endif /* __BIG_ENDIAN */ |
| |
| #else |
| |
| static int bits_to_user(unsigned long *bits, unsigned int maxbit, |
| unsigned int maxlen, void __user *p, int compat) |
| { |
| int len = BITS_TO_LONGS(maxbit) * sizeof(long); |
| |
| if (len > maxlen) |
| len = maxlen; |
| |
| return copy_to_user(p, bits, len) ? -EFAULT : len; |
| } |
| |
| #endif /* CONFIG_COMPAT */ |
| |
| static int str_to_user(const char *str, unsigned int maxlen, void __user *p) |
| { |
| int len; |
| |
| if (!str) |
| return -ENOENT; |
| |
| len = strlen(str) + 1; |
| if (len > maxlen) |
| len = maxlen; |
| |
| return copy_to_user(p, str, len) ? -EFAULT : len; |
| } |
| |
| #define OLD_KEY_MAX 0x1ff |
| static int handle_eviocgbit(struct input_dev *dev, |
| unsigned int type, unsigned int size, |
| void __user *p, int compat_mode) |
| { |
| static unsigned long keymax_warn_time; |
| unsigned long *bits; |
| int len; |
| |
| switch (type) { |
| |
| case 0: bits = dev->evbit; len = EV_MAX; break; |
| case EV_KEY: bits = dev->keybit; len = KEY_MAX; break; |
| case EV_REL: bits = dev->relbit; len = REL_MAX; break; |
| case EV_ABS: bits = dev->absbit; len = ABS_MAX; break; |
| case EV_MSC: bits = dev->mscbit; len = MSC_MAX; break; |
| case EV_LED: bits = dev->ledbit; len = LED_MAX; break; |
| case EV_SND: bits = dev->sndbit; len = SND_MAX; break; |
| case EV_FF: bits = dev->ffbit; len = FF_MAX; break; |
| case EV_SW: bits = dev->swbit; len = SW_MAX; break; |
| default: return -EINVAL; |
| } |
| |
| /* |
| * Work around bugs in userspace programs that like to do |
| * EVIOCGBIT(EV_KEY, KEY_MAX) and not realize that 'len' |
| * should be in bytes, not in bits. |
| */ |
| if (type == EV_KEY && size == OLD_KEY_MAX) { |
| len = OLD_KEY_MAX; |
| if (printk_timed_ratelimit(&keymax_warn_time, 10 * 1000)) |
| pr_warning("(EVIOCGBIT): Suspicious buffer size %u, " |
| "limiting output to %zu bytes. See " |
| "http://userweb.kernel.org/~dtor/eviocgbit-bug.html\n", |
| OLD_KEY_MAX, |
| BITS_TO_LONGS(OLD_KEY_MAX) * sizeof(long)); |
| } |
| |
| return bits_to_user(bits, len, size, p, compat_mode); |
| } |
| #undef OLD_KEY_MAX |
| |
| static int evdev_handle_get_keycode(struct input_dev *dev, void __user *p) |
| { |
| struct input_keymap_entry ke = { |
| .len = sizeof(unsigned int), |
| .flags = 0, |
| }; |
| int __user *ip = (int __user *)p; |
| int error; |
| |
| /* legacy case */ |
| if (copy_from_user(ke.scancode, p, sizeof(unsigned int))) |
| return -EFAULT; |
| |
| error = input_get_keycode(dev, &ke); |
| if (error) |
| return error; |
| |
| if (put_user(ke.keycode, ip + 1)) |
| return -EFAULT; |
| |
| return 0; |
| } |
| |
| static int evdev_handle_get_keycode_v2(struct input_dev *dev, void __user *p) |
| { |
| struct input_keymap_entry ke; |
| int error; |
| |
| if (copy_from_user(&ke, p, sizeof(ke))) |
| return -EFAULT; |
| |
| error = input_get_keycode(dev, &ke); |
| if (error) |
| return error; |
| |
| if (copy_to_user(p, &ke, sizeof(ke))) |
| return -EFAULT; |
| |
| return 0; |
| } |
| |
| static int evdev_handle_set_keycode(struct input_dev *dev, void __user *p) |
| { |
| struct input_keymap_entry ke = { |
| .len = sizeof(unsigned int), |
| .flags = 0, |
| }; |
| int __user *ip = (int __user *)p; |
| |
| if (copy_from_user(ke.scancode, p, sizeof(unsigned int))) |
| return -EFAULT; |
| |
| if (get_user(ke.keycode, ip + 1)) |
| return -EFAULT; |
| |
| return input_set_keycode(dev, &ke); |
| } |
| |
| static int evdev_handle_set_keycode_v2(struct input_dev *dev, void __user *p) |
| { |
| struct input_keymap_entry ke; |
| |
| if (copy_from_user(&ke, p, sizeof(ke))) |
| return -EFAULT; |
| |
| if (ke.len > sizeof(ke.scancode)) |
| return -EINVAL; |
| |
| return input_set_keycode(dev, &ke); |
| } |
| |
| static long evdev_do_ioctl(struct file *file, unsigned int cmd, |
| void __user *p, int compat_mode) |
| { |
| struct evdev_client *client = file->private_data; |
| struct evdev *evdev = client->evdev; |
| struct input_dev *dev = evdev->handle.dev; |
| struct input_absinfo abs; |
| struct ff_effect effect; |
| int __user *ip = (int __user *)p; |
| unsigned int i, t, u, v; |
| unsigned int size; |
| int error; |
| |
| /* First we check for fixed-length commands */ |
| switch (cmd) { |
| |
| case EVIOCGVERSION: |
| return put_user(EV_VERSION, ip); |
| |
| case EVIOCGID: |
| if (copy_to_user(p, &dev->id, sizeof(struct input_id))) |
| return -EFAULT; |
| return 0; |
| |
| case EVIOCGREP: |
| if (!test_bit(EV_REP, dev->evbit)) |
| return -ENOSYS; |
| if (put_user(dev->rep[REP_DELAY], ip)) |
| return -EFAULT; |
| if (put_user(dev->rep[REP_PERIOD], ip + 1)) |
| return -EFAULT; |
| return 0; |
| |
| case EVIOCSREP: |
| if (!test_bit(EV_REP, dev->evbit)) |
| return -ENOSYS; |
| if (get_user(u, ip)) |
| return -EFAULT; |
| if (get_user(v, ip + 1)) |
| return -EFAULT; |
| |
| input_inject_event(&evdev->handle, EV_REP, REP_DELAY, u); |
| input_inject_event(&evdev->handle, EV_REP, REP_PERIOD, v); |
| |
| return 0; |
| |
| case EVIOCRMFF: |
| return input_ff_erase(dev, (int)(unsigned long) p, file); |
| |
| case EVIOCGEFFECTS: |
| i = test_bit(EV_FF, dev->evbit) ? |
| dev->ff->max_effects : 0; |
| if (put_user(i, ip)) |
| return -EFAULT; |
| return 0; |
| |
| case EVIOCGRAB: |
| if (p) |
| return evdev_grab(evdev, client); |
| else |
| return evdev_ungrab(evdev, client); |
| |
| case EVIOCGKEYCODE: |
| return evdev_handle_get_keycode(dev, p); |
| |
| case EVIOCSKEYCODE: |
| return evdev_handle_set_keycode(dev, p); |
| |
| case EVIOCGKEYCODE_V2: |
| return evdev_handle_get_keycode_v2(dev, p); |
| |
| case EVIOCSKEYCODE_V2: |
| return evdev_handle_set_keycode_v2(dev, p); |
| } |
| |
| size = _IOC_SIZE(cmd); |
| |
| /* Now check variable-length commands */ |
| #define EVIOC_MASK_SIZE(nr) ((nr) & ~(_IOC_SIZEMASK << _IOC_SIZESHIFT)) |
| switch (EVIOC_MASK_SIZE(cmd)) { |
| |
| case EVIOCGPROP(0): |
| return bits_to_user(dev->propbit, INPUT_PROP_MAX, |
| size, p, compat_mode); |
| |
| case EVIOCGKEY(0): |
| return bits_to_user(dev->key, KEY_MAX, size, p, compat_mode); |
| |
| case EVIOCGLED(0): |
| return bits_to_user(dev->led, LED_MAX, size, p, compat_mode); |
| |
| case EVIOCGSND(0): |
| return bits_to_user(dev->snd, SND_MAX, size, p, compat_mode); |
| |
| case EVIOCGSW(0): |
| return bits_to_user(dev->sw, SW_MAX, size, p, compat_mode); |
| |
| case EVIOCGNAME(0): |
| return str_to_user(dev->name, size, p); |
| |
| case EVIOCGPHYS(0): |
| return str_to_user(dev->phys, size, p); |
| |
| case EVIOCGUNIQ(0): |
| return str_to_user(dev->uniq, size, p); |
| |
| case EVIOC_MASK_SIZE(EVIOCSFF): |
| if (input_ff_effect_from_user(p, size, &effect)) |
| return -EFAULT; |
| |
| error = input_ff_upload(dev, &effect, file); |
| |
| if (put_user(effect.id, &(((struct ff_effect __user *)p)->id))) |
| return -EFAULT; |
| |
| return error; |
| } |
| |
| /* Multi-number variable-length handlers */ |
| if (_IOC_TYPE(cmd) != 'E') |
| return -EINVAL; |
| |
| if (_IOC_DIR(cmd) == _IOC_READ) { |
| |
| if ((_IOC_NR(cmd) & ~EV_MAX) == _IOC_NR(EVIOCGBIT(0, 0))) |
| return handle_eviocgbit(dev, |
| _IOC_NR(cmd) & EV_MAX, size, |
| p, compat_mode); |
| |
| if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCGABS(0))) { |
| |
| if (!dev->absinfo) |
| return -EINVAL; |
| |
| t = _IOC_NR(cmd) & ABS_MAX; |
| abs = dev->absinfo[t]; |
| |
| if (copy_to_user(p, &abs, min_t(size_t, |
| size, sizeof(struct input_absinfo)))) |
| return -EFAULT; |
| |
| return 0; |
| } |
| } |
| |
| if (_IOC_DIR(cmd) == _IOC_WRITE) { |
| |
| if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCSABS(0))) { |
| |
| if (!dev->absinfo) |
| return -EINVAL; |
| |
| t = _IOC_NR(cmd) & ABS_MAX; |
| |
| if (copy_from_user(&abs, p, min_t(size_t, |
| size, sizeof(struct input_absinfo)))) |
| return -EFAULT; |
| |
| if (size < sizeof(struct input_absinfo)) |
| abs.resolution = 0; |
| |
| /* We can't change number of reserved MT slots */ |
| if (t == ABS_MT_SLOT) |
| return -EINVAL; |
| |
| /* |
| * Take event lock to ensure that we are not |
| * changing device parameters in the middle |
| * of event. |
| */ |
| spin_lock_irq(&dev->event_lock); |
| dev->absinfo[t] = abs; |
| spin_unlock_irq(&dev->event_lock); |
| |
| return 0; |
| } |
| } |
| |
| return -EINVAL; |
| } |
| |
| static long evdev_ioctl_handler(struct file *file, unsigned int cmd, |
| void __user *p, int compat_mode) |
| { |
| struct evdev_client *client = file->private_data; |
| struct evdev *evdev = client->evdev; |
| int retval; |
| |
| retval = mutex_lock_interruptible(&evdev->mutex); |
| if (retval) |
| return retval; |
| |
| if (!evdev->exist) { |
| retval = -ENODEV; |
| goto out; |
| } |
| |
| retval = evdev_do_ioctl(file, cmd, p, compat_mode); |
| |
| out: |
| mutex_unlock(&evdev->mutex); |
| return retval; |
| } |
| |
| static long evdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
| { |
| return evdev_ioctl_handler(file, cmd, (void __user *)arg, 0); |
| } |
| |
| #ifdef CONFIG_COMPAT |
| static long evdev_ioctl_compat(struct file *file, |
| unsigned int cmd, unsigned long arg) |
| { |
| return evdev_ioctl_handler(file, cmd, compat_ptr(arg), 1); |
| } |
| #endif |
| |
| static const struct file_operations evdev_fops = { |
| .owner = THIS_MODULE, |
| .read = evdev_read, |
| .write = evdev_write, |
| .poll = evdev_poll, |
| .open = evdev_open, |
| .release = evdev_release, |
| .unlocked_ioctl = evdev_ioctl, |
| #ifdef CONFIG_COMPAT |
| .compat_ioctl = evdev_ioctl_compat, |
| #endif |
| .fasync = evdev_fasync, |
| .flush = evdev_flush, |
| .llseek = no_llseek, |
| }; |
| |
| static int evdev_install_chrdev(struct evdev *evdev) |
| { |
| /* |
| * No need to do any locking here as calls to connect and |
| * disconnect are serialized by the input core |
| */ |
| evdev_table[evdev->minor] = evdev; |
| return 0; |
| } |
| |
| static void evdev_remove_chrdev(struct evdev *evdev) |
| { |
| /* |
| * Lock evdev table to prevent race with evdev_open() |
| */ |
| mutex_lock(&evdev_table_mutex); |
| evdev_table[evdev->minor] = NULL; |
| mutex_unlock(&evdev_table_mutex); |
| } |
| |
| /* |
| * Mark device non-existent. This disables writes, ioctls and |
| * prevents new users from opening the device. Already posted |
| * blocking reads will stay, however new ones will fail. |
| */ |
| static void evdev_mark_dead(struct evdev *evdev) |
| { |
| mutex_lock(&evdev->mutex); |
| evdev->exist = false; |
| mutex_unlock(&evdev->mutex); |
| } |
| |
| static void evdev_cleanup(struct evdev *evdev) |
| { |
| struct input_handle *handle = &evdev->handle; |
| |
| evdev_mark_dead(evdev); |
| evdev_hangup(evdev); |
| evdev_remove_chrdev(evdev); |
| |
| /* evdev is marked dead so no one else accesses evdev->open */ |
| if (evdev->open) { |
| input_flush_device(handle, NULL); |
| input_close_device(handle); |
| } |
| } |
| |
| /* |
| * Create new evdev device. Note that input core serializes calls |
| * to connect and disconnect so we don't need to lock evdev_table here. |
| */ |
| static int evdev_connect(struct input_handler *handler, struct input_dev *dev, |
| const struct input_device_id *id) |
| { |
| struct evdev *evdev; |
| int minor; |
| int error; |
| |
| for (minor = 0; minor < EVDEV_MINORS; minor++) |
| if (!evdev_table[minor]) |
| break; |
| |
| if (minor == EVDEV_MINORS) { |
| pr_err("no more free evdev devices\n"); |
| return -ENFILE; |
| } |
| |
| evdev = kzalloc(sizeof(struct evdev), GFP_KERNEL); |
| if (!evdev) |
| return -ENOMEM; |
| |
| INIT_LIST_HEAD(&evdev->client_list); |
| spin_lock_init(&evdev->client_lock); |
| mutex_init(&evdev->mutex); |
| init_waitqueue_head(&evdev->wait); |
| |
| dev_set_name(&evdev->dev, "event%d", minor); |
| evdev->exist = true; |
| evdev->minor = minor; |
| |
| evdev->handle.dev = input_get_device(dev); |
| evdev->handle.name = dev_name(&evdev->dev); |
| evdev->handle.handler = handler; |
| evdev->handle.private = evdev; |
| |
| evdev->dev.devt = MKDEV(INPUT_MAJOR, EVDEV_MINOR_BASE + minor); |
| evdev->dev.class = &input_class; |
| evdev->dev.parent = &dev->dev; |
| evdev->dev.release = evdev_free; |
| device_initialize(&evdev->dev); |
| |
| error = input_register_handle(&evdev->handle); |
| if (error) |
| goto err_free_evdev; |
| |
| error = evdev_install_chrdev(evdev); |
| if (error) |
| goto err_unregister_handle; |
| |
| error = device_add(&evdev->dev); |
| if (error) |
| goto err_cleanup_evdev; |
| |
| return 0; |
| |
| err_cleanup_evdev: |
| evdev_cleanup(evdev); |
| err_unregister_handle: |
| input_unregister_handle(&evdev->handle); |
| err_free_evdev: |
| put_device(&evdev->dev); |
| return error; |
| } |
| |
| static void evdev_disconnect(struct input_handle *handle) |
| { |
| struct evdev *evdev = handle->private; |
| |
| device_del(&evdev->dev); |
| evdev_cleanup(evdev); |
| input_unregister_handle(handle); |
| put_device(&evdev->dev); |
| } |
| |
| static const struct input_device_id evdev_ids[] = { |
| { .driver_info = 1 }, /* Matches all devices */ |
| { }, /* Terminating zero entry */ |
| }; |
| |
| MODULE_DEVICE_TABLE(input, evdev_ids); |
| |
| static struct input_handler evdev_handler = { |
| .event = evdev_event, |
| .connect = evdev_connect, |
| .disconnect = evdev_disconnect, |
| .fops = &evdev_fops, |
| .minor = EVDEV_MINOR_BASE, |
| .name = "evdev", |
| .id_table = evdev_ids, |
| }; |
| |
| static int __init evdev_init(void) |
| { |
| return input_register_handler(&evdev_handler); |
| } |
| |
| static void __exit evdev_exit(void) |
| { |
| input_unregister_handler(&evdev_handler); |
| } |
| |
| module_init(evdev_init); |
| module_exit(evdev_exit); |
| |
| MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>"); |
| MODULE_DESCRIPTION("Input driver event char devices"); |
| MODULE_LICENSE("GPL"); |