| /* |
| * 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/vmalloc.h> |
| #include <linux/mm.h> |
| #include <linux/module.h> |
| #include <linux/init.h> |
| #include <linux/input/mt.h> |
| #include <linux/major.h> |
| #include <linux/device.h> |
| #include <linux/cdev.h> |
| #include "input-compat.h" |
| |
| enum evdev_clock_type { |
| EV_CLK_REAL = 0, |
| EV_CLK_MONO, |
| EV_CLK_BOOT, |
| EV_CLK_MAX |
| }; |
| |
| struct evdev { |
| int open; |
| 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; |
| struct cdev cdev; |
| 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 fasync_struct *fasync; |
| struct evdev *evdev; |
| struct list_head node; |
| unsigned int clk_type; |
| bool revoked; |
| unsigned long *evmasks[EV_CNT]; |
| unsigned int bufsize; |
| struct input_event buffer[]; |
| }; |
| |
| static size_t evdev_get_mask_cnt(unsigned int type) |
| { |
| static const size_t counts[EV_CNT] = { |
| /* EV_SYN==0 is EV_CNT, _not_ SYN_CNT, see EVIOCGBIT */ |
| [EV_SYN] = EV_CNT, |
| [EV_KEY] = KEY_CNT, |
| [EV_REL] = REL_CNT, |
| [EV_ABS] = ABS_CNT, |
| [EV_MSC] = MSC_CNT, |
| [EV_SW] = SW_CNT, |
| [EV_LED] = LED_CNT, |
| [EV_SND] = SND_CNT, |
| [EV_FF] = FF_CNT, |
| }; |
| |
| return (type < EV_CNT) ? counts[type] : 0; |
| } |
| |
| /* requires the buffer lock to be held */ |
| static bool __evdev_is_filtered(struct evdev_client *client, |
| unsigned int type, |
| unsigned int code) |
| { |
| unsigned long *mask; |
| size_t cnt; |
| |
| /* EV_SYN and unknown codes are never filtered */ |
| if (type == EV_SYN || type >= EV_CNT) |
| return false; |
| |
| /* first test whether the type is filtered */ |
| mask = client->evmasks[0]; |
| if (mask && !test_bit(type, mask)) |
| return true; |
| |
| /* unknown values are never filtered */ |
| cnt = evdev_get_mask_cnt(type); |
| if (!cnt || code >= cnt) |
| return false; |
| |
| mask = client->evmasks[type]; |
| return mask && !test_bit(code, mask); |
| } |
| |
| /* flush queued events of type @type, caller must hold client->buffer_lock */ |
| static void __evdev_flush_queue(struct evdev_client *client, unsigned int type) |
| { |
| unsigned int i, head, num; |
| unsigned int mask = client->bufsize - 1; |
| bool is_report; |
| struct input_event *ev; |
| |
| BUG_ON(type == EV_SYN); |
| |
| head = client->tail; |
| client->packet_head = client->tail; |
| |
| /* init to 1 so a leading SYN_REPORT will not be dropped */ |
| num = 1; |
| |
| for (i = client->tail; i != client->head; i = (i + 1) & mask) { |
| ev = &client->buffer[i]; |
| is_report = ev->type == EV_SYN && ev->code == SYN_REPORT; |
| |
| if (ev->type == type) { |
| /* drop matched entry */ |
| continue; |
| } else if (is_report && !num) { |
| /* drop empty SYN_REPORT groups */ |
| continue; |
| } else if (head != i) { |
| /* move entry to fill the gap */ |
| client->buffer[head] = *ev; |
| } |
| |
| num++; |
| head = (head + 1) & mask; |
| |
| if (is_report) { |
| num = 0; |
| client->packet_head = head; |
| } |
| } |
| |
| client->head = head; |
| } |
| |
| static void __evdev_queue_syn_dropped(struct evdev_client *client) |
| { |
| struct input_event ev; |
| ktime_t time; |
| struct timespec64 ts; |
| |
| time = client->clk_type == EV_CLK_REAL ? |
| ktime_get_real() : |
| client->clk_type == EV_CLK_MONO ? |
| ktime_get() : |
| ktime_get_boottime(); |
| |
| ts = ktime_to_timespec64(time); |
| ev.input_event_sec = ts.tv_sec; |
| ev.input_event_usec = ts.tv_nsec / NSEC_PER_USEC; |
| ev.type = EV_SYN; |
| ev.code = SYN_DROPPED; |
| ev.value = 0; |
| |
| client->buffer[client->head++] = ev; |
| client->head &= client->bufsize - 1; |
| |
| if (unlikely(client->head == client->tail)) { |
| /* drop queue but keep our SYN_DROPPED event */ |
| client->tail = (client->head - 1) & (client->bufsize - 1); |
| client->packet_head = client->tail; |
| } |
| } |
| |
| static void evdev_queue_syn_dropped(struct evdev_client *client) |
| { |
| unsigned long flags; |
| |
| spin_lock_irqsave(&client->buffer_lock, flags); |
| __evdev_queue_syn_dropped(client); |
| spin_unlock_irqrestore(&client->buffer_lock, flags); |
| } |
| |
| static int evdev_set_clk_type(struct evdev_client *client, unsigned int clkid) |
| { |
| unsigned long flags; |
| unsigned int clk_type; |
| |
| switch (clkid) { |
| |
| case CLOCK_REALTIME: |
| clk_type = EV_CLK_REAL; |
| break; |
| case CLOCK_MONOTONIC: |
| clk_type = EV_CLK_MONO; |
| break; |
| case CLOCK_BOOTTIME: |
| clk_type = EV_CLK_BOOT; |
| break; |
| default: |
| return -EINVAL; |
| } |
| |
| if (client->clk_type != clk_type) { |
| client->clk_type = clk_type; |
| |
| /* |
| * Flush pending events and queue SYN_DROPPED event, |
| * but only if the queue is not empty. |
| */ |
| spin_lock_irqsave(&client->buffer_lock, flags); |
| |
| if (client->head != client->tail) { |
| client->packet_head = client->head = client->tail; |
| __evdev_queue_syn_dropped(client); |
| } |
| |
| spin_unlock_irqrestore(&client->buffer_lock, flags); |
| } |
| |
| return 0; |
| } |
| |
| static void __pass_event(struct evdev_client *client, |
| const struct input_event *event) |
| { |
| 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] = (struct input_event) { |
| .input_event_sec = event->input_event_sec, |
| .input_event_usec = event->input_event_usec, |
| .type = EV_SYN, |
| .code = SYN_DROPPED, |
| .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); |
| } |
| } |
| |
| static void evdev_pass_values(struct evdev_client *client, |
| const struct input_value *vals, unsigned int count, |
| ktime_t *ev_time) |
| { |
| struct evdev *evdev = client->evdev; |
| const struct input_value *v; |
| struct input_event event; |
| struct timespec64 ts; |
| bool wakeup = false; |
| |
| if (client->revoked) |
| return; |
| |
| ts = ktime_to_timespec64(ev_time[client->clk_type]); |
| event.input_event_sec = ts.tv_sec; |
| event.input_event_usec = ts.tv_nsec / NSEC_PER_USEC; |
| |
| /* Interrupts are disabled, just acquire the lock. */ |
| spin_lock(&client->buffer_lock); |
| |
| for (v = vals; v != vals + count; v++) { |
| if (__evdev_is_filtered(client, v->type, v->code)) |
| continue; |
| |
| if (v->type == EV_SYN && v->code == SYN_REPORT) { |
| /* drop empty SYN_REPORT */ |
| if (client->packet_head == client->head) |
| continue; |
| |
| wakeup = true; |
| } |
| |
| event.type = v->type; |
| event.code = v->code; |
| event.value = v->value; |
| __pass_event(client, &event); |
| } |
| |
| spin_unlock(&client->buffer_lock); |
| |
| if (wakeup) |
| wake_up_interruptible(&evdev->wait); |
| } |
| |
| /* |
| * Pass incoming events to all connected clients. |
| */ |
| static void evdev_events(struct input_handle *handle, |
| const struct input_value *vals, unsigned int count) |
| { |
| struct evdev *evdev = handle->private; |
| struct evdev_client *client; |
| ktime_t ev_time[EV_CLK_MAX]; |
| |
| ev_time[EV_CLK_MONO] = ktime_get(); |
| ev_time[EV_CLK_REAL] = ktime_mono_to_real(ev_time[EV_CLK_MONO]); |
| ev_time[EV_CLK_BOOT] = ktime_mono_to_any(ev_time[EV_CLK_MONO], |
| TK_OFFS_BOOT); |
| |
| rcu_read_lock(); |
| |
| client = rcu_dereference(evdev->grab); |
| |
| if (client) |
| evdev_pass_values(client, vals, count, ev_time); |
| else |
| list_for_each_entry_rcu(client, &evdev->client_list, node) |
| evdev_pass_values(client, vals, count, ev_time); |
| |
| rcu_read_unlock(); |
| } |
| |
| /* |
| * Pass incoming event to all connected clients. |
| */ |
| static void evdev_event(struct input_handle *handle, |
| unsigned int type, unsigned int code, int value) |
| { |
| struct input_value vals[] = { { type, code, value } }; |
| |
| evdev_events(handle, vals, 1); |
| } |
| |
| 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 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) |
| { |
| struct evdev_client *grab = rcu_dereference_protected(evdev->grab, |
| lockdep_is_held(&evdev->mutex)); |
| |
| if (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; |
| unsigned int i; |
| |
| mutex_lock(&evdev->mutex); |
| |
| if (evdev->exist && !client->revoked) |
| input_flush_device(&evdev->handle, file); |
| |
| evdev_ungrab(evdev, client); |
| mutex_unlock(&evdev->mutex); |
| |
| evdev_detach_client(evdev, client); |
| |
| for (i = 0; i < EV_CNT; ++i) |
| bitmap_free(client->evmasks[i]); |
| |
| kvfree(client); |
| |
| evdev_close_device(evdev); |
| |
| 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 = container_of(inode->i_cdev, struct evdev, cdev); |
| unsigned int bufsize = evdev_compute_buffer_size(evdev->handle.dev); |
| unsigned int size = sizeof(struct evdev_client) + |
| bufsize * sizeof(struct input_event); |
| struct evdev_client *client; |
| int error; |
| |
| client = kzalloc(size, GFP_KERNEL | __GFP_NOWARN); |
| if (!client) |
| client = vzalloc(size); |
| if (!client) |
| return -ENOMEM; |
| |
| client->bufsize = bufsize; |
| spin_lock_init(&client->buffer_lock); |
| 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); |
| kvfree(client); |
| 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 = 0; |
| |
| if (count != 0 && count < input_event_size()) |
| return -EINVAL; |
| |
| retval = mutex_lock_interruptible(&evdev->mutex); |
| if (retval) |
| return retval; |
| |
| if (!evdev->exist || client->revoked) { |
| retval = -ENODEV; |
| goto out; |
| } |
| |
| while (retval + input_event_size() <= count) { |
| |
| 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); |
| cond_resched(); |
| } |
| |
| 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; |
| } |
| |
| 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; |
| size_t read = 0; |
| int error; |
| |
| if (count != 0 && count < input_event_size()) |
| return -EINVAL; |
| |
| for (;;) { |
| if (!evdev->exist || client->revoked) |
| return -ENODEV; |
| |
| if (client->packet_head == client->tail && |
| (file->f_flags & O_NONBLOCK)) |
| return -EAGAIN; |
| |
| /* |
| * count == 0 is special - no IO is done but we check |
| * for error conditions (see above). |
| */ |
| if (count == 0) |
| break; |
| |
| while (read + input_event_size() <= count && |
| evdev_fetch_next_event(client, &event)) { |
| |
| if (input_event_to_user(buffer + read, &event)) |
| return -EFAULT; |
| |
| read += input_event_size(); |
| } |
| |
| if (read) |
| break; |
| |
| if (!(file->f_flags & O_NONBLOCK)) { |
| error = wait_event_interruptible(evdev->wait, |
| client->packet_head != client->tail || |
| !evdev->exist || client->revoked); |
| if (error) |
| return error; |
| } |
| } |
| |
| return read; |
| } |
| |
| /* No kernel lock - fine */ |
| static __poll_t evdev_poll(struct file *file, poll_table *wait) |
| { |
| struct evdev_client *client = file->private_data; |
| struct evdev *evdev = client->evdev; |
| __poll_t mask; |
| |
| poll_wait(file, &evdev->wait, wait); |
| |
| if (evdev->exist && !client->revoked) |
| mask = EPOLLOUT | EPOLLWRNORM; |
| else |
| mask = EPOLLHUP | EPOLLERR; |
| |
| if (client->packet_head != client->tail) |
| mask |= EPOLLIN | EPOLLRDNORM; |
| |
| 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; |
| } |
| |
| static int bits_from_user(unsigned long *bits, unsigned int maxbit, |
| unsigned int maxlen, const void __user *p, int compat) |
| { |
| int len, i; |
| |
| if (compat) { |
| if (maxlen % sizeof(compat_long_t)) |
| return -EINVAL; |
| |
| 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_from_user((compat_long_t *) bits + |
| i + 1 - ((i % 2) << 1), |
| (compat_long_t __user *) p + i, |
| sizeof(compat_long_t))) |
| return -EFAULT; |
| if (i % 2) |
| *((compat_long_t *) bits + i - 1) = 0; |
| |
| } else { |
| if (maxlen % sizeof(long)) |
| return -EINVAL; |
| |
| len = BITS_TO_LONGS(maxbit) * sizeof(long); |
| if (len > maxlen) |
| len = maxlen; |
| |
| if (copy_from_user(bits, p, 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; |
| } |
| |
| static int bits_from_user(unsigned long *bits, unsigned int maxbit, |
| unsigned int maxlen, const void __user *p, int compat) |
| { |
| size_t chunk_size = compat ? sizeof(compat_long_t) : sizeof(long); |
| int len; |
| |
| if (maxlen % chunk_size) |
| return -EINVAL; |
| |
| len = compat ? BITS_TO_LONGS_COMPAT(maxbit) : BITS_TO_LONGS(maxbit); |
| len *= chunk_size; |
| if (len > maxlen) |
| len = maxlen; |
| |
| return copy_from_user(bits, p, 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; |
| } |
| |
| static int bits_from_user(unsigned long *bits, unsigned int maxbit, |
| unsigned int maxlen, const void __user *p, int compat) |
| { |
| int len; |
| |
| if (maxlen % sizeof(long)) |
| return -EINVAL; |
| |
| len = BITS_TO_LONGS(maxbit) * sizeof(long); |
| if (len > maxlen) |
| len = maxlen; |
| |
| return copy_from_user(bits, p, 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; |
| } |
| |
| static int handle_eviocgbit(struct input_dev *dev, |
| unsigned int type, unsigned int size, |
| void __user *p, int compat_mode) |
| { |
| 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; |
| } |
| |
| return bits_to_user(bits, len, size, p, compat_mode); |
| } |
| |
| 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); |
| } |
| |
| /* |
| * If we transfer state to the user, we should flush all pending events |
| * of the same type from the client's queue. Otherwise, they might end up |
| * with duplicate events, which can screw up client's state tracking. |
| * If bits_to_user fails after flushing the queue, we queue a SYN_DROPPED |
| * event so user-space will notice missing events. |
| * |
| * LOCKING: |
| * We need to take event_lock before buffer_lock to avoid dead-locks. But we |
| * need the even_lock only to guarantee consistent state. We can safely release |
| * it while flushing the queue. This allows input-core to handle filters while |
| * we flush the queue. |
| */ |
| static int evdev_handle_get_val(struct evdev_client *client, |
| struct input_dev *dev, unsigned int type, |
| unsigned long *bits, unsigned int maxbit, |
| unsigned int maxlen, void __user *p, |
| int compat) |
| { |
| int ret; |
| unsigned long *mem; |
| |
| mem = bitmap_alloc(maxbit, GFP_KERNEL); |
| if (!mem) |
| return -ENOMEM; |
| |
| spin_lock_irq(&dev->event_lock); |
| spin_lock(&client->buffer_lock); |
| |
| bitmap_copy(mem, bits, maxbit); |
| |
| spin_unlock(&dev->event_lock); |
| |
| __evdev_flush_queue(client, type); |
| |
| spin_unlock_irq(&client->buffer_lock); |
| |
| ret = bits_to_user(mem, maxbit, maxlen, p, compat); |
| if (ret < 0) |
| evdev_queue_syn_dropped(client); |
| |
| bitmap_free(mem); |
| |
| return ret; |
| } |
| |
| static int evdev_handle_mt_request(struct input_dev *dev, |
| unsigned int size, |
| int __user *ip) |
| { |
| const struct input_mt *mt = dev->mt; |
| unsigned int code; |
| int max_slots; |
| int i; |
| |
| if (get_user(code, &ip[0])) |
| return -EFAULT; |
| if (!mt || !input_is_mt_value(code)) |
| return -EINVAL; |
| |
| max_slots = (size - sizeof(__u32)) / sizeof(__s32); |
| for (i = 0; i < mt->num_slots && i < max_slots; i++) { |
| int value = input_mt_get_value(&mt->slots[i], code); |
| if (put_user(value, &ip[1 + i])) |
| return -EFAULT; |
| } |
| |
| return 0; |
| } |
| |
| static int evdev_revoke(struct evdev *evdev, struct evdev_client *client, |
| struct file *file) |
| { |
| client->revoked = true; |
| evdev_ungrab(evdev, client); |
| input_flush_device(&evdev->handle, file); |
| wake_up_interruptible(&evdev->wait); |
| |
| return 0; |
| } |
| |
| /* must be called with evdev-mutex held */ |
| static int evdev_set_mask(struct evdev_client *client, |
| unsigned int type, |
| const void __user *codes, |
| u32 codes_size, |
| int compat) |
| { |
| unsigned long flags, *mask, *oldmask; |
| size_t cnt; |
| int error; |
| |
| /* we allow unknown types and 'codes_size > size' for forward-compat */ |
| cnt = evdev_get_mask_cnt(type); |
| if (!cnt) |
| return 0; |
| |
| mask = bitmap_zalloc(cnt, GFP_KERNEL); |
| if (!mask) |
| return -ENOMEM; |
| |
| error = bits_from_user(mask, cnt - 1, codes_size, codes, compat); |
| if (error < 0) { |
| bitmap_free(mask); |
| return error; |
| } |
| |
| spin_lock_irqsave(&client->buffer_lock, flags); |
| oldmask = client->evmasks[type]; |
| client->evmasks[type] = mask; |
| spin_unlock_irqrestore(&client->buffer_lock, flags); |
| |
| bitmap_free(oldmask); |
| |
| return 0; |
| } |
| |
| /* must be called with evdev-mutex held */ |
| static int evdev_get_mask(struct evdev_client *client, |
| unsigned int type, |
| void __user *codes, |
| u32 codes_size, |
| int compat) |
| { |
| unsigned long *mask; |
| size_t cnt, size, xfer_size; |
| int i; |
| int error; |
| |
| /* we allow unknown types and 'codes_size > size' for forward-compat */ |
| cnt = evdev_get_mask_cnt(type); |
| size = sizeof(unsigned long) * BITS_TO_LONGS(cnt); |
| xfer_size = min_t(size_t, codes_size, size); |
| |
| if (cnt > 0) { |
| mask = client->evmasks[type]; |
| if (mask) { |
| error = bits_to_user(mask, cnt - 1, |
| xfer_size, codes, compat); |
| if (error < 0) |
| return error; |
| } else { |
| /* fake mask with all bits set */ |
| for (i = 0; i < xfer_size; i++) |
| if (put_user(0xffU, (u8 __user *)codes + i)) |
| return -EFAULT; |
| } |
| } |
| |
| if (xfer_size < codes_size) |
| if (clear_user(codes + xfer_size, codes_size - xfer_size)) |
| return -EFAULT; |
| |
| return 0; |
| } |
| |
| 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 input_mask mask; |
| 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 EVIOCREVOKE: |
| if (p) |
| return -EINVAL; |
| else |
| return evdev_revoke(evdev, client, file); |
| |
| case EVIOCGMASK: { |
| void __user *codes_ptr; |
| |
| if (copy_from_user(&mask, p, sizeof(mask))) |
| return -EFAULT; |
| |
| codes_ptr = (void __user *)(unsigned long)mask.codes_ptr; |
| return evdev_get_mask(client, |
| mask.type, codes_ptr, mask.codes_size, |
| compat_mode); |
| } |
| |
| case EVIOCSMASK: { |
| const void __user *codes_ptr; |
| |
| if (copy_from_user(&mask, p, sizeof(mask))) |
| return -EFAULT; |
| |
| codes_ptr = (const void __user *)(unsigned long)mask.codes_ptr; |
| return evdev_set_mask(client, |
| mask.type, codes_ptr, mask.codes_size, |
| compat_mode); |
| } |
| |
| case EVIOCSCLOCKID: |
| if (copy_from_user(&i, p, sizeof(unsigned int))) |
| return -EFAULT; |
| |
| return evdev_set_clk_type(client, i); |
| |
| 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 EVIOCGMTSLOTS(0): |
| return evdev_handle_mt_request(dev, size, ip); |
| |
| case EVIOCGKEY(0): |
| return evdev_handle_get_val(client, dev, EV_KEY, dev->key, |
| KEY_MAX, size, p, compat_mode); |
| |
| case EVIOCGLED(0): |
| return evdev_handle_get_val(client, dev, EV_LED, dev->led, |
| LED_MAX, size, p, compat_mode); |
| |
| case EVIOCGSND(0): |
| return evdev_handle_get_val(client, dev, EV_SND, dev->snd, |
| SND_MAX, size, p, compat_mode); |
| |
| case EVIOCGSW(0): |
| return evdev_handle_get_val(client, dev, EV_SW, 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 (error) |
| return error; |
| |
| if (put_user(effect.id, &(((struct ff_effect __user *)p)->id))) |
| return -EFAULT; |
| |
| return 0; |
| } |
| |
| /* 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 || client->revoked) { |
| 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, |
| .llseek = no_llseek, |
| }; |
| |
| /* |
| * 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 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. |
| */ |
| static int evdev_connect(struct input_handler *handler, struct input_dev *dev, |
| const struct input_device_id *id) |
| { |
| struct evdev *evdev; |
| int minor; |
| int dev_no; |
| int error; |
| |
| minor = input_get_new_minor(EVDEV_MINOR_BASE, EVDEV_MINORS, true); |
| if (minor < 0) { |
| error = minor; |
| pr_err("failed to reserve new minor: %d\n", error); |
| return error; |
| } |
| |
| evdev = kzalloc(sizeof(struct evdev), GFP_KERNEL); |
| if (!evdev) { |
| error = -ENOMEM; |
| goto err_free_minor; |
| } |
| |
| INIT_LIST_HEAD(&evdev->client_list); |
| spin_lock_init(&evdev->client_lock); |
| mutex_init(&evdev->mutex); |
| init_waitqueue_head(&evdev->wait); |
| evdev->exist = true; |
| |
| dev_no = minor; |
| /* Normalize device number if it falls into legacy range */ |
| if (dev_no < EVDEV_MINOR_BASE + EVDEV_MINORS) |
| dev_no -= EVDEV_MINOR_BASE; |
| dev_set_name(&evdev->dev, "event%d", dev_no); |
| |
| 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, 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; |
| |
| cdev_init(&evdev->cdev, &evdev_fops); |
| |
| error = cdev_device_add(&evdev->cdev, &evdev->dev); |
| if (error) |
| goto err_cleanup_evdev; |
| |
| return 0; |
| |
| err_cleanup_evdev: |
| evdev_cleanup(evdev); |
| input_unregister_handle(&evdev->handle); |
| err_free_evdev: |
| put_device(&evdev->dev); |
| err_free_minor: |
| input_free_minor(minor); |
| return error; |
| } |
| |
| static void evdev_disconnect(struct input_handle *handle) |
| { |
| struct evdev *evdev = handle->private; |
| |
| cdev_device_del(&evdev->cdev, &evdev->dev); |
| evdev_cleanup(evdev); |
| input_free_minor(MINOR(evdev->dev.devt)); |
| 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, |
| .events = evdev_events, |
| .connect = evdev_connect, |
| .disconnect = evdev_disconnect, |
| .legacy_minors = true, |
| .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"); |