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1446 lines
32 KiB
1446 lines
32 KiB
// SPDX-License-Identifier: GPL-2.0-only |
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/* |
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* Event char devices, giving access to raw input device events. |
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* |
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* Copyright (c) 1999-2002 Vojtech Pavlik |
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*/ |
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|
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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
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|
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#define EVDEV_MINOR_BASE 64 |
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#define EVDEV_MINORS 32 |
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#define EVDEV_MIN_BUFFER_SIZE 64U |
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#define EVDEV_BUF_PACKETS 8 |
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#include <linux/poll.h> |
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#include <linux/sched.h> |
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#include <linux/slab.h> |
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#include <linux/vmalloc.h> |
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#include <linux/mm.h> |
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#include <linux/module.h> |
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#include <linux/init.h> |
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#include <linux/input/mt.h> |
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#include <linux/major.h> |
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#include <linux/device.h> |
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#include <linux/cdev.h> |
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#include "input-compat.h" |
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struct evdev { |
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int open; |
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struct input_handle handle; |
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struct evdev_client __rcu *grab; |
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struct list_head client_list; |
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spinlock_t client_lock; /* protects client_list */ |
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struct mutex mutex; |
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struct device dev; |
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struct cdev cdev; |
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bool exist; |
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}; |
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struct evdev_client { |
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unsigned int head; |
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unsigned int tail; |
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unsigned int packet_head; /* [future] position of the first element of next packet */ |
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spinlock_t buffer_lock; /* protects access to buffer, head and tail */ |
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wait_queue_head_t wait; |
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struct fasync_struct *fasync; |
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struct evdev *evdev; |
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struct list_head node; |
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enum input_clock_type clk_type; |
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bool revoked; |
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unsigned long *evmasks[EV_CNT]; |
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unsigned int bufsize; |
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struct input_event buffer[]; |
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}; |
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|
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static size_t evdev_get_mask_cnt(unsigned int type) |
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{ |
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static const size_t counts[EV_CNT] = { |
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/* EV_SYN==0 is EV_CNT, _not_ SYN_CNT, see EVIOCGBIT */ |
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[EV_SYN] = EV_CNT, |
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[EV_KEY] = KEY_CNT, |
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[EV_REL] = REL_CNT, |
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[EV_ABS] = ABS_CNT, |
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[EV_MSC] = MSC_CNT, |
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[EV_SW] = SW_CNT, |
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[EV_LED] = LED_CNT, |
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[EV_SND] = SND_CNT, |
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[EV_FF] = FF_CNT, |
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}; |
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|
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return (type < EV_CNT) ? counts[type] : 0; |
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} |
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|
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/* requires the buffer lock to be held */ |
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static bool __evdev_is_filtered(struct evdev_client *client, |
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unsigned int type, |
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unsigned int code) |
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{ |
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unsigned long *mask; |
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size_t cnt; |
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|
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/* EV_SYN and unknown codes are never filtered */ |
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if (type == EV_SYN || type >= EV_CNT) |
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return false; |
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|
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/* first test whether the type is filtered */ |
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mask = client->evmasks[0]; |
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if (mask && !test_bit(type, mask)) |
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return true; |
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|
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/* unknown values are never filtered */ |
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cnt = evdev_get_mask_cnt(type); |
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if (!cnt || code >= cnt) |
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return false; |
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mask = client->evmasks[type]; |
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return mask && !test_bit(code, mask); |
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} |
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|
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/* flush queued events of type @type, caller must hold client->buffer_lock */ |
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static void __evdev_flush_queue(struct evdev_client *client, unsigned int type) |
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{ |
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unsigned int i, head, num; |
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unsigned int mask = client->bufsize - 1; |
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bool is_report; |
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struct input_event *ev; |
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BUG_ON(type == EV_SYN); |
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head = client->tail; |
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client->packet_head = client->tail; |
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|
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/* init to 1 so a leading SYN_REPORT will not be dropped */ |
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num = 1; |
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|
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for (i = client->tail; i != client->head; i = (i + 1) & mask) { |
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ev = &client->buffer[i]; |
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is_report = ev->type == EV_SYN && ev->code == SYN_REPORT; |
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|
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if (ev->type == type) { |
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/* drop matched entry */ |
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continue; |
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} else if (is_report && !num) { |
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/* drop empty SYN_REPORT groups */ |
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continue; |
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} else if (head != i) { |
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/* move entry to fill the gap */ |
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client->buffer[head] = *ev; |
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} |
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num++; |
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head = (head + 1) & mask; |
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|
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if (is_report) { |
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num = 0; |
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client->packet_head = head; |
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} |
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} |
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client->head = head; |
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} |
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static void __evdev_queue_syn_dropped(struct evdev_client *client) |
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{ |
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ktime_t *ev_time = input_get_timestamp(client->evdev->handle.dev); |
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struct timespec64 ts = ktime_to_timespec64(ev_time[client->clk_type]); |
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struct input_event ev; |
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ev.input_event_sec = ts.tv_sec; |
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ev.input_event_usec = ts.tv_nsec / NSEC_PER_USEC; |
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ev.type = EV_SYN; |
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ev.code = SYN_DROPPED; |
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ev.value = 0; |
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client->buffer[client->head++] = ev; |
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client->head &= client->bufsize - 1; |
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|
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if (unlikely(client->head == client->tail)) { |
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/* drop queue but keep our SYN_DROPPED event */ |
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client->tail = (client->head - 1) & (client->bufsize - 1); |
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client->packet_head = client->tail; |
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} |
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} |
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static void evdev_queue_syn_dropped(struct evdev_client *client) |
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{ |
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unsigned long flags; |
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|
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spin_lock_irqsave(&client->buffer_lock, flags); |
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__evdev_queue_syn_dropped(client); |
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spin_unlock_irqrestore(&client->buffer_lock, flags); |
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} |
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static int evdev_set_clk_type(struct evdev_client *client, unsigned int clkid) |
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{ |
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unsigned long flags; |
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enum input_clock_type clk_type; |
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|
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switch (clkid) { |
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|
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case CLOCK_REALTIME: |
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clk_type = INPUT_CLK_REAL; |
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break; |
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case CLOCK_MONOTONIC: |
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clk_type = INPUT_CLK_MONO; |
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break; |
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case CLOCK_BOOTTIME: |
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clk_type = INPUT_CLK_BOOT; |
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break; |
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default: |
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return -EINVAL; |
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} |
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if (client->clk_type != clk_type) { |
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client->clk_type = clk_type; |
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|
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/* |
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* Flush pending events and queue SYN_DROPPED event, |
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* but only if the queue is not empty. |
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*/ |
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spin_lock_irqsave(&client->buffer_lock, flags); |
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|
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if (client->head != client->tail) { |
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client->packet_head = client->head = client->tail; |
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__evdev_queue_syn_dropped(client); |
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} |
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spin_unlock_irqrestore(&client->buffer_lock, flags); |
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} |
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return 0; |
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} |
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static void __pass_event(struct evdev_client *client, |
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const struct input_event *event) |
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{ |
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client->buffer[client->head++] = *event; |
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client->head &= client->bufsize - 1; |
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|
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if (unlikely(client->head == client->tail)) { |
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/* |
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* This effectively "drops" all unconsumed events, leaving |
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* EV_SYN/SYN_DROPPED plus the newest event in the queue. |
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*/ |
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client->tail = (client->head - 2) & (client->bufsize - 1); |
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client->buffer[client->tail] = (struct input_event) { |
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.input_event_sec = event->input_event_sec, |
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.input_event_usec = event->input_event_usec, |
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.type = EV_SYN, |
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.code = SYN_DROPPED, |
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.value = 0, |
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}; |
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client->packet_head = client->tail; |
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} |
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if (event->type == EV_SYN && event->code == SYN_REPORT) { |
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client->packet_head = client->head; |
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kill_fasync(&client->fasync, SIGIO, POLL_IN); |
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} |
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} |
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static void evdev_pass_values(struct evdev_client *client, |
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const struct input_value *vals, unsigned int count, |
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ktime_t *ev_time) |
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{ |
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const struct input_value *v; |
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struct input_event event; |
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struct timespec64 ts; |
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bool wakeup = false; |
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|
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if (client->revoked) |
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return; |
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ts = ktime_to_timespec64(ev_time[client->clk_type]); |
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event.input_event_sec = ts.tv_sec; |
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event.input_event_usec = ts.tv_nsec / NSEC_PER_USEC; |
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|
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/* Interrupts are disabled, just acquire the lock. */ |
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spin_lock(&client->buffer_lock); |
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for (v = vals; v != vals + count; v++) { |
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if (__evdev_is_filtered(client, v->type, v->code)) |
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continue; |
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if (v->type == EV_SYN && v->code == SYN_REPORT) { |
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/* drop empty SYN_REPORT */ |
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if (client->packet_head == client->head) |
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continue; |
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|
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wakeup = true; |
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} |
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event.type = v->type; |
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event.code = v->code; |
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event.value = v->value; |
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__pass_event(client, &event); |
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} |
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spin_unlock(&client->buffer_lock); |
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if (wakeup) |
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wake_up_interruptible_poll(&client->wait, |
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EPOLLIN | EPOLLOUT | EPOLLRDNORM | EPOLLWRNORM); |
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} |
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|
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/* |
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* Pass incoming events to all connected clients. |
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*/ |
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static void evdev_events(struct input_handle *handle, |
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const struct input_value *vals, unsigned int count) |
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{ |
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struct evdev *evdev = handle->private; |
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struct evdev_client *client; |
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ktime_t *ev_time = input_get_timestamp(handle->dev); |
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rcu_read_lock(); |
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client = rcu_dereference(evdev->grab); |
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if (client) |
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evdev_pass_values(client, vals, count, ev_time); |
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else |
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list_for_each_entry_rcu(client, &evdev->client_list, node) |
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evdev_pass_values(client, vals, count, ev_time); |
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rcu_read_unlock(); |
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} |
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/* |
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* Pass incoming event to all connected clients. |
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*/ |
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static void evdev_event(struct input_handle *handle, |
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unsigned int type, unsigned int code, int value) |
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{ |
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struct input_value vals[] = { { type, code, value } }; |
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evdev_events(handle, vals, 1); |
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} |
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static int evdev_fasync(int fd, struct file *file, int on) |
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{ |
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struct evdev_client *client = file->private_data; |
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return fasync_helper(fd, file, on, &client->fasync); |
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} |
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static void evdev_free(struct device *dev) |
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{ |
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struct evdev *evdev = container_of(dev, struct evdev, dev); |
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|
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input_put_device(evdev->handle.dev); |
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kfree(evdev); |
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} |
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/* |
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* Grabs an event device (along with underlying input device). |
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* This function is called with evdev->mutex taken. |
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*/ |
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static int evdev_grab(struct evdev *evdev, struct evdev_client *client) |
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{ |
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int error; |
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|
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if (evdev->grab) |
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return -EBUSY; |
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error = input_grab_device(&evdev->handle); |
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if (error) |
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return error; |
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rcu_assign_pointer(evdev->grab, client); |
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return 0; |
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} |
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static int evdev_ungrab(struct evdev *evdev, struct evdev_client *client) |
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{ |
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struct evdev_client *grab = rcu_dereference_protected(evdev->grab, |
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lockdep_is_held(&evdev->mutex)); |
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if (grab != client) |
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return -EINVAL; |
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rcu_assign_pointer(evdev->grab, NULL); |
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synchronize_rcu(); |
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input_release_device(&evdev->handle); |
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return 0; |
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} |
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static void evdev_attach_client(struct evdev *evdev, |
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struct evdev_client *client) |
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{ |
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spin_lock(&evdev->client_lock); |
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list_add_tail_rcu(&client->node, &evdev->client_list); |
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spin_unlock(&evdev->client_lock); |
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} |
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|
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static void evdev_detach_client(struct evdev *evdev, |
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struct evdev_client *client) |
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{ |
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spin_lock(&evdev->client_lock); |
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list_del_rcu(&client->node); |
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spin_unlock(&evdev->client_lock); |
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synchronize_rcu(); |
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} |
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|
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static int evdev_open_device(struct evdev *evdev) |
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{ |
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int retval; |
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|
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retval = mutex_lock_interruptible(&evdev->mutex); |
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if (retval) |
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return retval; |
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|
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if (!evdev->exist) |
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retval = -ENODEV; |
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else if (!evdev->open++) { |
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retval = input_open_device(&evdev->handle); |
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if (retval) |
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evdev->open--; |
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} |
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mutex_unlock(&evdev->mutex); |
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return retval; |
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} |
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|
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static void evdev_close_device(struct evdev *evdev) |
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{ |
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mutex_lock(&evdev->mutex); |
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|
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if (evdev->exist && !--evdev->open) |
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input_close_device(&evdev->handle); |
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|
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mutex_unlock(&evdev->mutex); |
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} |
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|
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/* |
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* Wake up users waiting for IO so they can disconnect from |
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* dead device. |
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*/ |
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static void evdev_hangup(struct evdev *evdev) |
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{ |
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struct evdev_client *client; |
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|
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spin_lock(&evdev->client_lock); |
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list_for_each_entry(client, &evdev->client_list, node) { |
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kill_fasync(&client->fasync, SIGIO, POLL_HUP); |
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wake_up_interruptible_poll(&client->wait, EPOLLHUP | EPOLLERR); |
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} |
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spin_unlock(&evdev->client_lock); |
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} |
|
|
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static int evdev_release(struct inode *inode, struct file *file) |
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{ |
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struct evdev_client *client = file->private_data; |
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struct evdev *evdev = client->evdev; |
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unsigned int i; |
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|
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mutex_lock(&evdev->mutex); |
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|
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if (evdev->exist && !client->revoked) |
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input_flush_device(&evdev->handle, file); |
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|
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evdev_ungrab(evdev, client); |
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mutex_unlock(&evdev->mutex); |
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|
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evdev_detach_client(evdev, client); |
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|
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for (i = 0; i < EV_CNT; ++i) |
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bitmap_free(client->evmasks[i]); |
|
|
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kvfree(client); |
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|
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evdev_close_device(evdev); |
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|
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return 0; |
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} |
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|
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static unsigned int evdev_compute_buffer_size(struct input_dev *dev) |
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{ |
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unsigned int n_events = |
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max(dev->hint_events_per_packet * EVDEV_BUF_PACKETS, |
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EVDEV_MIN_BUFFER_SIZE); |
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|
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return roundup_pow_of_two(n_events); |
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} |
|
|
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static int evdev_open(struct inode *inode, struct file *file) |
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{ |
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struct evdev *evdev = container_of(inode->i_cdev, struct evdev, cdev); |
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unsigned int bufsize = evdev_compute_buffer_size(evdev->handle.dev); |
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struct evdev_client *client; |
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int error; |
|
|
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client = kvzalloc(struct_size(client, buffer, bufsize), GFP_KERNEL); |
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if (!client) |
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return -ENOMEM; |
|
|
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init_waitqueue_head(&client->wait); |
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client->bufsize = bufsize; |
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spin_lock_init(&client->buffer_lock); |
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client->evdev = evdev; |
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evdev_attach_client(evdev, client); |
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|
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error = evdev_open_device(evdev); |
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if (error) |
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goto err_free_client; |
|
|
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file->private_data = client; |
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stream_open(inode, file); |
|
|
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return 0; |
|
|
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err_free_client: |
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evdev_detach_client(evdev, client); |
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kvfree(client); |
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return error; |
|
} |
|
|
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static ssize_t evdev_write(struct file *file, const char __user *buffer, |
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size_t count, loff_t *ppos) |
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{ |
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struct evdev_client *client = file->private_data; |
|
struct evdev *evdev = client->evdev; |
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struct input_event event; |
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int retval = 0; |
|
|
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if (count != 0 && count < input_event_size()) |
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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, |
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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(client->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, &client->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_poll(&client->wait, EPOLLHUP | EPOLLERR); |
|
|
|
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); |
|
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 <[email protected]>"); |
|
MODULE_DESCRIPTION("Input driver event char devices"); |
|
MODULE_LICENSE("GPL");
|
|
|