+++ /dev/null
-/*
- * kmscon - Character-Device Session
- *
- * Copyright (c) 2012 David Herrmann <dh.herrmann@googlemail.com>
- *
- * Permission is hereby granted, free of charge, to any person obtaining
- * a copy of this software and associated documentation files
- * (the "Software"), to deal in the Software without restriction, including
- * without limitation the rights to use, copy, modify, merge, publish,
- * distribute, sublicense, and/or sell copies of the Software, and to
- * permit persons to whom the Software is furnished to do so, subject to
- * the following conditions:
- *
- * The above copyright notice and this permission notice shall be included
- * in all copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
- * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
- * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
- * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
- * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
- * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
- * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
- */
-
-/*
- * Character-Device Session
- */
-
-#define FUSE_USE_VERSION 29
-
-#include <errno.h>
-#include <fcntl.h>
-#include <linux/kd.h>
-#include <linux/major.h>
-#include <linux/vt.h>
-#include <pthread.h>
-#include <signal.h>
-#include <stdlib.h>
-#include <string.h>
-#include <sys/epoll.h>
-#include <termio.h>
-#include <termios.h>
-#include <unistd.h>
-#include "kmscon_cdev.h"
-#include "kmscon_seat.h"
-#include "shl_array.h"
-#include "shl_dlist.h"
-#include "shl_log.h"
-#include "shl_ring.h"
-#include "tsm_screen.h"
-#include "tsm_vte.h"
-#include "uterm_input.h"
-
-#include <fuse/fuse.h>
-#include <fuse/fuse_common.h>
-#include <fuse/fuse_lowlevel.h>
-#include <fuse/fuse_opt.h>
-#include <fuse/cuse_lowlevel.h>
-
-#define LOG_SUBSYSTEM "cdev"
-
-struct kmscon_cdev {
- struct kmscon_seat *seat;
- struct ev_eloop *eloop;
- struct uterm_input *input;
- struct kmscon_session *s;
- struct ev_fd *efd;
- unsigned int minor;
-
- struct fuse_session *session;
- int fd;
- struct fuse_chan *channel;
-
- size_t bufsize;
- char *buf;
-
- struct shl_dlist clients;
- int error;
-};
-
-struct cdev_client {
- struct shl_dlist list;
- struct kmscon_cdev *cdev;
- bool dead;
-
- struct tsm_screen *screen;
- struct tsm_vte *vte;
-
- bool active;
- struct kmscon_session *s;
-
- struct fuse_pollhandle *ph;
- struct shl_ring *ring;
- struct shl_dlist readers;
-
- long kdmode;
- long kbmode;
-
- struct vt_mode vtmode;
- struct fuse_ctx user;
- bool pending_switch;
-
- struct shl_dlist waiters;
-};
-
-struct cdev_reader {
- struct shl_dlist list;
- bool killed;
- fuse_req_t req;
- size_t len;
-};
-
-struct cdev_waiter {
- struct shl_dlist list;
- bool killed;
- fuse_req_t req;
-};
-
-static pthread_mutex_t cdev_lock = PTHREAD_MUTEX_INITIALIZER;
-static struct shl_array *cdev_ids = NULL;
-
-static int cdev_allocate_id(void)
-{
- static const bool init = true;
- int ret, len, i;
-
- pthread_mutex_lock(&cdev_lock);
-
- if (!cdev_ids) {
- ret = shl_array_new(&cdev_ids, sizeof(bool), 4);
- if (ret)
- goto err_unlock;
- }
-
- len = shl_array_get_length(cdev_ids);
- for (i = 0; i < len; ++i)
- if (!*SHL_ARRAY_AT(cdev_ids, bool, i))
- break;
-
- if (i >= len) {
- ret = shl_array_push(cdev_ids, &init);
- if (ret)
- goto err_unlock;
- ret = len;
- } else {
- *SHL_ARRAY_AT(cdev_ids, bool, i) = true;
- ret = i;
- }
-
-err_unlock:
- pthread_mutex_unlock(&cdev_lock);
- return (ret < 0) ? ret : (ret + 16384);
-}
-
-/*
- * Cdev Clients
- * As opposed to kernel VTs, we only provide one single char-dev per seat and
- * each client that opens it is managed separately. Hence, it is not possible to
- * use such a VT shared by two clients except if you pass the FD between the
- * clients. This has several advantages and avoids many bugs in the kernel VT
- * implementation.
- * For every user opening a /dev/ttyF<seat> device, a separate cdev_client is
- * created. A cdev_client emulates a single kernel VT but is managed as a
- * dedicated kmscon_session on its seat. We start a kmscon_terminal as backend
- * so you actually can run "agetty" on this fake-VT. When set into graphical
- * mode, the terminal is suspended and you can run an XServer on it. We emulate
- * the VT-switching signal-API, too. We release all DRM devices if a fake-VT is
- * active and reacquire them afterwards. This allows the clients to actually
- * implement graphical terminals. However, if you fail to release the DRM
- * devices, we actually try to kill the fake-VT so we can get access again.
- */
-
-static void reader_interrupt(fuse_req_t req, void *data)
-{
- struct cdev_reader *reader = data;
-
- if (!reader)
- return;
-
- reader->killed = true;
-}
-
-static int reader_new(struct cdev_reader **out, struct cdev_client *client,
- fuse_req_t req)
-{
- struct cdev_reader *reader;
-
- if (fuse_req_interrupted(req))
- return -ENOENT;
-
- reader = malloc(sizeof(*reader));
- if (!reader)
- return -ENOMEM;
- memset(reader, 0, sizeof(*reader));
- reader->req = req;
- fuse_req_interrupt_func(req, reader_interrupt, reader);
- if (reader->killed) {
- fuse_req_interrupt_func(req, NULL, NULL);
- free(reader);
- return -ENOENT;
- }
-
- shl_dlist_link_tail(&client->readers, &reader->list);
- *out = reader;
- return 0;
-}
-
-static void reader_free(struct cdev_reader *reader, int error)
-{
- shl_dlist_unlink(&reader->list);
- if (reader->req) {
- fuse_req_interrupt_func(reader->req, NULL, NULL);
- fuse_reply_err(reader->req, -error);
- }
- free(reader);
-}
-
-static int reader_release(struct cdev_reader *reader, const char *buf,
- size_t len)
-{
- int ret;
-
- fuse_req_interrupt_func(reader->req, NULL, NULL);
- ret = fuse_reply_buf(reader->req, buf, len);
- reader->req = NULL;
- reader_free(reader, 0);
- return ret;
-}
-
-static void waiter_interrupt(fuse_req_t req, void *data)
-{
- struct cdev_waiter *waiter = data;
-
- if (!waiter)
- return;
-
- waiter->killed = true;
-}
-
-static int waiter_new(struct cdev_waiter **out, struct cdev_client *client,
- fuse_req_t req)
-{
- struct cdev_waiter *waiter;
-
- if (fuse_req_interrupted(req))
- return -ENOENT;
-
- waiter = malloc(sizeof(*waiter));
- if (!waiter)
- return -ENOMEM;
- memset(waiter, 0, sizeof(*waiter));
- waiter->req = req;
- fuse_req_interrupt_func(req, waiter_interrupt, waiter);
- if (waiter->killed) {
- fuse_req_interrupt_func(req, NULL, NULL);
- free(waiter);
- return -ENOENT;
- }
-
- shl_dlist_link_tail(&client->waiters, &waiter->list);
- *out = waiter;
- return 0;
-}
-
-static void waiter_free(struct cdev_waiter *waiter, int error)
-{
- shl_dlist_unlink(&waiter->list);
- if (waiter->req) {
- fuse_req_interrupt_func(waiter->req, NULL, NULL);
- fuse_reply_err(waiter->req, -error);
- }
- free(waiter);
-}
-
-static int waiter_release(struct cdev_waiter *waiter)
-{
- int ret;
-
- fuse_req_interrupt_func(waiter->req, NULL, NULL);
- ret = fuse_reply_ioctl(waiter->req, 0, NULL, 0);
- waiter->req = NULL;
- waiter_free(waiter, 0);
- return ret;
-}
-
-static void client_vte_event(struct tsm_vte *vte, const char *u8, size_t len,
- void *data)
-{
- struct cdev_client *client = data;
- struct cdev_reader *reader;
- int ret;
- bool was_empty;
- const char *buf;
- size_t size;
-
- /* TODO: we should have a maximum buffer size here */
- was_empty = shl_ring_is_empty(client->ring);
- ret = shl_ring_write(client->ring, u8, len);
- if (ret)
- log_warning("cannot resize buffer for cdev client: %d", ret);
-
- if (shl_ring_is_empty(client->ring))
- return;
-
- if (was_empty && client->ph) {
- fuse_notify_poll(client->ph);
- fuse_pollhandle_destroy(client->ph);
- client->ph = NULL;
- }
-
- while (!shl_dlist_empty(&client->readers)) {
- reader = shl_dlist_entry(client->readers.next,
- struct cdev_reader, list);
- if (reader->killed)
- continue;
-
- /* TODO: fix filling the whole buffer instead of returning
- * partial buffers when the ring data is split */
- buf = shl_ring_peek(client->ring, &size, 0);
- if (!size)
- break;
- if (size > reader->len)
- size = reader->len;
-
- ret = reader_release(reader, buf, size);
- if (ret < 0)
- continue;
- shl_ring_drop(client->ring, size);
- }
-}
-
-static void client_input_event(struct uterm_input *input,
- struct uterm_input_event *ev,
- void *data)
-{
- struct cdev_client *client = data;
-
- if (!client->active || ev->handled)
- return;
-
- /* we drop all input in K_OFF mode */
- if (client->kbmode == K_OFF)
- return;
-
- /* TODO: see kmscon_terminal on how this is special. We need to fix this
- * when xkbcommon provides the first multi-sym events. */
- if (ev->num_syms > 1)
- return;
-
- if (tsm_vte_handle_keyboard(client->vte, ev->keysyms[0], ev->ascii,
- ev->mods, ev->codepoints[0])) {
- tsm_screen_sb_reset(client->screen);
- ev->handled = true;
- }
-}
-
-static int client_activate(struct cdev_client *client)
-{
- int ret;
- struct cdev_waiter *waiter;
-
- /* TODO: Check whether we have CAP_KILL capability during startup */
- if (client->vtmode.mode == VT_PROCESS && client->vtmode.acqsig) {
- ret = kill(client->user.pid, client->vtmode.acqsig);
- if (ret)
- log_warning("cannot send activation signal to process %d of cdev client %p (%d): %m",
- client->user.pid, client, errno);
- }
-
- while (!shl_dlist_empty(&client->waiters)) {
- waiter = shl_dlist_entry(client->waiters.next,
- struct cdev_waiter, list);
- if (waiter->killed)
- waiter_free(waiter, 0);
- else
- waiter_release(waiter);
- }
-
- client->active = true;
- return 0;
-}
-
-static int client_deactivate(struct cdev_client *client)
-{
- int ret;
-
- if (client->vtmode.mode == VT_PROCESS && client->vtmode.relsig) {
- ret = kill(client->user.pid, client->vtmode.relsig);
- if (ret)
- log_warning("cannot send deactivation signal to process %d of cdev client %p (%d): %m",
- client->user.pid, client, errno);
- client->pending_switch = true;
- return -EINPROGRESS;
- }
-
- client->active = false;
- return 0;
-}
-
-static void client_kill(struct cdev_client *client)
-{
- struct cdev_reader *reader;
- struct cdev_waiter *waiter;
-
- if (client->dead) {
- log_error("killing already dead client");
- return;
- }
-
- log_debug("kill fake TTY client %p", client);
-
- client->dead = true;
-
- if (client->ph) {
- fuse_notify_poll(client->ph);
- fuse_pollhandle_destroy(client->ph);
- }
-
- while (!shl_dlist_empty(&client->readers)) {
- reader = shl_dlist_entry(client->readers.next,
- struct cdev_reader, list);
- reader_free(reader, -EPIPE);
- }
-
- while (!shl_dlist_empty(&client->waiters)) {
- waiter = shl_dlist_entry(client->waiters.next,
- struct cdev_waiter, list);
- waiter_free(waiter, -EPIPE);
- }
-
- uterm_input_unregister_cb(client->cdev->input, client_input_event,
- client);
- tsm_vte_unref(client->vte);
- tsm_screen_unref(client->screen);
- shl_ring_free(client->ring);
-}
-
-static int client_session_event(struct kmscon_session *s,
- struct kmscon_session_event *ev,
- void *data)
-{
- struct cdev_client *client = data;
-
- switch (ev->type) {
- case KMSCON_SESSION_ACTIVATE:
- return client_activate(client);
- case KMSCON_SESSION_DEACTIVATE:
- return client_deactivate(client);
- case KMSCON_SESSION_UNREGISTER:
- client_kill(client);
- break;
- }
-
- return 0;
-}
-
-static int client_new(struct cdev_client **out, struct kmscon_cdev *cdev)
-{
- struct cdev_client *client;
- int ret;
-
- client = malloc(sizeof(*client));
- if (!client)
- return -ENOMEM;
- memset(client, 0, sizeof(*client));
- client->cdev = cdev;
- client->kdmode = KD_TEXT;
- client->kbmode = K_UNICODE;
- client->vtmode.mode = VT_AUTO;
- shl_dlist_init(&client->readers);
- shl_dlist_init(&client->waiters);
-
- log_debug("new fake TTY client %p", client);
-
- ret = shl_ring_new(&client->ring);
- if (ret) {
- log_error("cannot create ring buffer for new cdev client: %d",
- ret);
- goto err_free;
- }
-
- /* TODO: Share the terminal-handling with the terminal-session. We
- * currently just create the screen/vte objects here to get meaningful
- * parsers. However, we should also correctly handled the terminal as is
- * and draw it to the screen if in text-mode.
- * This is nearly identical to the terminal-session so we should share
- * the implementation between both instead of doing everything ourself
- * here. */
-
- ret = tsm_screen_new(&client->screen, log_llog, NULL);
- if (ret) {
- log_error("cannot create TSM screen for new cdev client: %d",
- ret);
- goto err_ring;
- }
-
- ret = tsm_vte_new(&client->vte, client->screen, client_vte_event,
- client, log_llog, NULL);
- if (ret) {
- log_error("cannot create TSM VTE for new cdev client: %d",
- ret);
- goto err_screen;
- }
-
- ret = uterm_input_register_cb(cdev->input, client_input_event, client);
- if (ret) {
- log_error("cannot register input callback for cdev client: %d",
- ret);
- goto err_vte;
- }
-
- ret = kmscon_seat_register_session(cdev->seat, &client->s,
- client_session_event, client);
- if (ret) {
- log_error("cannot register session for cdev client: %d", ret);
- goto err_input;
- }
-
- shl_dlist_link(&cdev->clients, &client->list);
- *out = client;
- return 0;
-
-err_input:
- uterm_input_unregister_cb(cdev->input, client_input_event, client);
-err_vte:
- tsm_vte_unref(client->vte);
-err_screen:
- tsm_screen_unref(client->screen);
-err_ring:
- shl_ring_free(client->ring);
-err_free:
- free(client);
- return ret;
-}
-
-static void client_destroy(struct cdev_client *client)
-{
- log_debug("destroy client %p", client);
-
- if (!client->dead)
- kmscon_session_unregister(client->s);
- shl_dlist_unlink(&client->list);
- free(client);
-}
-
-/* This must be called after each event dispatch round. It cleans up all
- * interrupted/killed readers. The readers cannot be released right away due to
- * heavy locking inside of FUSE. We have to delay these tasks and clean up after
- * each dispatch round. */
-static void client_cleanup(struct cdev_client *client)
-{
- struct shl_dlist *i, *tmp;
- struct cdev_reader *reader;
- struct cdev_waiter *waiter;
-
- shl_dlist_for_each_safe(i, tmp, &client->readers) {
- reader = shl_dlist_entry(i, struct cdev_reader, list);
- if (reader->killed)
- reader_free(reader, -ENOENT);
- }
-
- shl_dlist_for_each_safe(i, tmp, &client->waiters) {
- waiter = shl_dlist_entry(i, struct cdev_waiter, list);
- if (waiter->killed)
- waiter_free(waiter, -ENOENT);
- }
-}
-
-/*
- * FUSE low-level ops
- * This implements all the file-system operations on the character-device. It is
- * important that we handle interrupts correctly (ENOENT) and never loose any
- * data. This is all single threaded as it is not performance critical at all.
- */
-
-static void ll_open(fuse_req_t req, struct fuse_file_info *fi)
-{
- struct kmscon_cdev *cdev = fuse_req_userdata(req);
- struct cdev_client *client;
- int ret;
-
- ret = client_new(&client, cdev);
- if (ret)
- goto err_out;
-
- fi->fh = (long)client;
- fi->nonseekable = 1;
- fi->direct_io = 1;
- ret = fuse_reply_open(req, fi);
- if (ret < 0)
- client_destroy(client);
- else
- kmscon_session_enable(client->s);
-
- return;
-
-err_out:
- fuse_reply_err(req, -ret);
-}
-
-static void ll_release(fuse_req_t req, struct fuse_file_info *fi)
-{
- struct cdev_client *client = (void*)fi->fh;
-
- if (!client) {
- fuse_reply_err(req, EINVAL);
- return;
- }
-
- client_destroy(client);
- fuse_reply_err(req, 0);
-}
-
-static void ll_read(fuse_req_t req, size_t size, off_t off,
- struct fuse_file_info *fi)
-{
- struct cdev_client *client = (void*)fi->fh;
- struct cdev_reader *reader;
- const char *buf;
- size_t len;
- int ret;
-
- if (!client) {
- fuse_reply_err(req, EINVAL);
- return;
- }
-
- if (client->dead) {
- fuse_reply_err(req, EPIPE);
- return;
- }
-
- if (off != 0) {
- fuse_reply_err(req, EINVAL);
- return;
- }
-
- if (!size) {
- fuse_reply_buf(req, "", 0);
- return;
- }
-
- /* TODO: use a proper intermediate buffer as this might return only
- * partial data */
- buf = shl_ring_peek(client->ring, &len, 0);
- if (!len) {
- if (fi->flags & O_NONBLOCK) {
- fuse_reply_err(req, EAGAIN);
- return;
- }
-
- ret = reader_new(&reader, client, req);
- if (ret) {
- fuse_reply_err(req, -ret);
- return;
- }
-
- reader->len = size;
- return;
- }
-
- if (len > size)
- len = size;
- ret = fuse_reply_buf(req, buf, len);
- if (ret < 0)
- return;
- shl_ring_drop(client->ring, len);
-}
-
-static void ll_write(fuse_req_t req, const char *buf, size_t size, off_t off,
- struct fuse_file_info *fi)
-{
- struct cdev_client *client = (void*)fi->fh;
- int ret;
-
- if (!client) {
- fuse_reply_err(req, EINVAL);
- return;
- }
-
- if (client->dead) {
- fuse_reply_err(req, EPIPE);
- return;
- }
-
- ret = fuse_reply_write(req, size);
- if (ret < 0)
- return;
- tsm_vte_input(client->vte, buf, size);
-}
-
-static void ll_poll(fuse_req_t req, struct fuse_file_info *fi,
- struct fuse_pollhandle *ph)
-{
- struct cdev_client *client = (void*)fi->fh;
- unsigned int flags;
-
- if (!client) {
- fuse_reply_err(req, EINVAL);
- return;
- }
-
- if (client->dead) {
- if (ph)
- fuse_pollhandle_destroy(ph);
- fuse_reply_poll(req, EPOLLHUP | EPOLLIN | EPOLLOUT |
- EPOLLWRNORM | EPOLLRDNORM);
- return;
- }
-
- if (client->ph)
- fuse_pollhandle_destroy(client->ph);
- client->ph = ph;
-
- flags = EPOLLOUT | EPOLLWRNORM;
- if (!shl_ring_is_empty(client->ring))
- flags |= EPOLLIN | EPOLLRDNORM;
-
- fuse_reply_poll(req, flags);
-}
-
-static void ioctl_TCFLSH(struct cdev_client *client, fuse_req_t req, int val)
-{
- switch (val) {
- case TCIFLUSH:
- shl_ring_flush(client->ring);
- break;
- case TCIOFLUSH:
- shl_ring_flush(client->ring);
- /* fallthrough */
- case TCOFLUSH:
- /* nothing to do; we have no output queue */
- break;
- default:
- fuse_reply_err(req, EINVAL);
- return;
- }
-
- fuse_reply_ioctl(req, 0, NULL, 0);
-}
-
-static void ioctl_VT_ACTIVATE(struct cdev_client *client, fuse_req_t req,
- int val)
-{
- unsigned short target, id;
-
- id = client->cdev->minor;
- target = val;
-
- if (id == target) {
- kmscon_session_schedule(client->s);
- } else {
- kmscon_seat_schedule(client->cdev->seat, target);
- }
-
- fuse_reply_ioctl(req, 0, NULL, 0);
-}
-
-static void ioctl_VT_WAITACTIVE(struct cdev_client *client, fuse_req_t req,
- int val)
-{
- int ret;
- struct cdev_waiter *waiter;
-
- if (client->active) {
- fuse_reply_ioctl(req, 0, NULL, 0);
- return;
- }
-
- ret = waiter_new(&waiter, client, req);
- if (ret) {
- fuse_reply_err(req, -ret);
- return;
- }
-}
-
-static void ioctl_VT_GETSTATE(struct cdev_client *client, fuse_req_t req)
-{
- struct vt_stat buf;
- unsigned short id;
-
- id = client->cdev->minor;
- if (id == 0 || id == 1)
- id = 2;
-
- memset(&buf, 0, sizeof(buf));
- buf.v_active = client->active ? id : 1;
- buf.v_signal = 0;
- buf.v_state = ~0;
-
- fuse_reply_ioctl(req, 0, &buf, sizeof(buf));
-}
-
-static void ioctl_VT_GETMODE(struct cdev_client *client, fuse_req_t req)
-{
- fuse_reply_ioctl(req, 0, &client->vtmode, sizeof(client->vtmode));
-}
-
-static void ioctl_VT_SETMODE(struct cdev_client *client, fuse_req_t req,
- struct vt_mode *mode)
-{
- bool proc;
-
- proc = mode->mode == VT_PROCESS;
-
- /* TODO: implement "waitv" logic */
- if (mode->waitv) {
- fuse_reply_err(req, EINVAL);
- return;
- }
-
- if (mode->frsig)
- log_debug("cdev client uses non-zero 'frsig' in VT_SETMODE: %d",
- mode->frsig);
-
- if (mode->mode != VT_AUTO && mode->mode != VT_PROCESS) {
- fuse_reply_err(req, EINVAL);
- return;
- }
-
- if (proc && (mode->relsig > SIGRTMAX || mode->acqsig > SIGRTMAX ||
- mode->relsig < 0 || mode->acqsig < 0)) {
- fuse_reply_err(req, EINVAL);
- return;
- }
-
- memcpy(&client->vtmode, mode, sizeof(*mode));
- memcpy(&client->user, fuse_req_ctx(req), sizeof(client->user));
- fuse_reply_ioctl(req, 0, NULL, 0);
-}
-
-static void ioctl_VT_RELDISP(struct cdev_client *client, fuse_req_t req,
- int val)
-{
- if (client->pending_switch) {
- client->pending_switch = false;
- if (val > 0) {
- client->active = false;
- kmscon_session_notify_deactivated(client->s);
- }
- }
-
- fuse_reply_ioctl(req, 0, NULL, 0);
-}
-
-static void ioctl_KDGETMODE(struct cdev_client *client, fuse_req_t req)
-{
- fuse_reply_ioctl(req, 0, &client->kdmode, sizeof(long));
-}
-
-static void ioctl_KDSETMODE(struct cdev_client *client, fuse_req_t req,
- long val)
-{
- int ret;
-
- switch (val) {
- case KD_TEXT:
- ret = kmscon_session_set_foreground(client->s);
- if (ret) {
- fuse_reply_err(req, -ret);
- return;
- }
- client->kdmode = KD_TEXT;
- break;
- case KD_GRAPHICS:
- ret = kmscon_session_set_background(client->s);
- if (ret) {
- fuse_reply_err(req, -ret);
- return;
- }
- client->kdmode = KD_GRAPHICS;
- break;
- default:
- fuse_reply_err(req, EINVAL);
- return;
- }
-
- fuse_reply_ioctl(req, 0, NULL, 0);
-}
-
-static void ioctl_KDGKBMODE(struct cdev_client *client, fuse_req_t req)
-{
- fuse_reply_ioctl(req, 0, &client->kbmode, sizeof(long));
-}
-
-static void ioctl_KDSKBMODE(struct cdev_client *client, fuse_req_t req,
- long val)
-{
- switch (val) {
- case K_RAW:
- case K_UNICODE:
- case K_OFF:
- /* TODO: we handle K_RAW/K_UNICODE the same way as it is unclear
- * what K_RAW should do? */
- client->kbmode = val;
- fuse_reply_ioctl(req, 0, NULL, 0);
- break;
- case K_XLATE:
- case K_MEDIUMRAW:
- /* TODO: what do these do? */
- fuse_reply_err(req, EOPNOTSUPP);
- break;
- default:
- fuse_reply_err(req, EINVAL);
- break;
- }
-}
-
-static bool ioctl_param(fuse_req_t req, void *arg, size_t in_want,
- size_t in_have, size_t out_want, size_t out_have)
-{
- bool retry;
- struct iovec in, out;
- size_t in_num, out_num;
-
- retry = false;
- memset(&in, 0, sizeof(in));
- in_num = 0;
- memset(&out, 0, sizeof(out));
- out_num = 0;
-
- if (in_want) {
- if (!in_have) {
- retry = true;
- } else if (in_have < in_want) {
- fuse_reply_err(req, EFAULT);
- return true;
- }
-
- in.iov_base = arg;
- in.iov_len = in_want;
- in_num = 1;
- }
- if (out_want) {
- if (!out_have) {
- retry = true;
- } else if (out_have < out_want) {
- fuse_reply_err(req, EFAULT);
- return true;
- }
-
- out.iov_base = arg;
- out.iov_len = out_want;
- out_num = 1;
- }
-
- if (retry)
- fuse_reply_ioctl_retry(req, in_num ? &in : NULL, in_num,
- out_num ? &out : NULL, out_num);
- return retry;
-}
-
-static void ll_ioctl(fuse_req_t req, int cmd, void *arg,
- struct fuse_file_info *fi, unsigned int flags,
- const void *in_buf, size_t in_bufsz, size_t out_bufsz)
-{
- struct cdev_client *client = (void*)fi->fh;
- bool compat;
-
- if (!client) {
- fuse_reply_err(req, EINVAL);
- return;
- }
-
- if (client->dead) {
- fuse_reply_err(req, EPIPE);
- return;
- }
-
- /* TODO: fix compat-ioctls */
- compat = !!(flags & FUSE_IOCTL_COMPAT);
- if (compat) {
- fuse_reply_err(req, EOPNOTSUPP);
- return;
- }
-
- switch (cmd) {
- case TCFLSH:
- if (ioctl_param(req, arg, 0, in_bufsz, 0, out_bufsz))
- return;
- ioctl_TCFLSH(client, req, (long)arg);
- break;
- case VT_ACTIVATE:
- if (ioctl_param(req, arg, 0, in_bufsz, 0, out_bufsz))
- return;
- ioctl_VT_ACTIVATE(client, req, (long)arg);
- break;
- case VT_WAITACTIVE:
- if (ioctl_param(req, arg, 0, in_bufsz, 0, out_bufsz))
- return;
- ioctl_VT_WAITACTIVE(client, req, (long)arg);
- break;
- case VT_GETSTATE:
- if (ioctl_param(req, arg, 0, in_bufsz,
- sizeof(struct vt_stat), out_bufsz))
- return;
- ioctl_VT_GETSTATE(client, req);
- break;
- case VT_OPENQRY:
- if (ioctl_param(req, arg, 0, in_bufsz,
- sizeof(int), out_bufsz))
- return;
- fuse_reply_err(req, EOPNOTSUPP);
- break;
- case VT_GETMODE:
- if (ioctl_param(req, arg, 0, in_bufsz,
- sizeof(struct vt_mode), out_bufsz))
- return;
- ioctl_VT_GETMODE(client, req);
- break;
- case VT_SETMODE:
- if (ioctl_param(req, arg, sizeof(struct vt_mode), in_bufsz,
- 0, out_bufsz))
- return;
- ioctl_VT_SETMODE(client, req, (struct vt_mode*)in_buf);
- break;
- case VT_RELDISP:
- if (ioctl_param(req, arg, 0, in_bufsz, 0, out_bufsz))
- return;
- ioctl_VT_RELDISP(client, req, (long)arg);
- break;
- case KDGETMODE:
- if (ioctl_param(req, arg, 0, in_bufsz,
- sizeof(long), out_bufsz))
- return;
- ioctl_KDGETMODE(client, req);
- break;
- case KDSETMODE:
- if (ioctl_param(req, arg, 0, in_bufsz, 0, out_bufsz))
- return;
- ioctl_KDSETMODE(client, req, (long)arg);
- break;
- case KDGKBMODE:
- if (ioctl_param(req, arg, 0, in_bufsz,
- sizeof(long), out_bufsz))
- return;
- ioctl_KDGKBMODE(client, req);
- break;
- case KDSKBMODE:
- if (ioctl_param(req, arg, 0, in_bufsz, 0, out_bufsz))
- return;
- ioctl_KDSKBMODE(client, req, (long)arg);
- break;
- case TCGETS:
- if (ioctl_param(req, arg, 0, in_bufsz,
- sizeof(struct termios), out_bufsz))
- return;
- fuse_reply_err(req, EOPNOTSUPP);
- break;
- case TCSETS:
- if (ioctl_param(req, arg, sizeof(struct termios), in_bufsz,
- 0, out_bufsz))
- return;
- fuse_reply_err(req, EOPNOTSUPP);
- break;
- case TCSETSW:
- if (ioctl_param(req, arg, sizeof(struct termios), in_bufsz,
- 0, out_bufsz))
- return;
- fuse_reply_err(req, EOPNOTSUPP);
- break;
- case TCSETSF:
- if (ioctl_param(req, arg, sizeof(struct termios), in_bufsz,
- 0, out_bufsz))
- return;
- fuse_reply_err(req, EOPNOTSUPP);
- break;
- default:
- fuse_reply_err(req, EINVAL);
- break;
- }
-}
-
-static void ll_destroy(void *data) {
- struct kmscon_cdev *cdev = data;
- struct cdev_client *client;
-
- /* on unexpected shutdown this releases all currently open clients */
- while (!shl_dlist_empty(&cdev->clients)) {
- client = shl_dlist_entry(cdev->clients.next,
- struct cdev_client, list);
- client_destroy(client);
- }
-}
-
-static const struct cuse_lowlevel_ops ll_ops = {
- .init = NULL,
- .destroy = ll_destroy,
- .open = ll_open,
- .release = ll_release,
- .read = ll_read,
- .write = ll_write,
- .poll = ll_poll,
- .ioctl = ll_ioctl,
- .flush = NULL,
- .fsync = NULL,
-};
-
-/*
- * FUSE channel ops
- * The connection to the FUSE kernel module is done via a file-descriptor.
- * Writing to it is synchronous, so the commands that we write are _immediately_
- * executed and return the result to us. Furthermore, write() is always
- * non-blocking and always succeeds so no reason to watch for EAGAIN.
- * Reading from the FD, on the other hand, may block if there is no data
- * available. However, we only read if the FD was signaled readable so we can
- * use a blocking FD to avoid any side-effects. The kernel maintains an
- * event-queue that we read from. So there may be pending events that we haven't
- * read but which affect the calls that we write to the kernel. This is
- * important when handling interrupts.
- * chan_receive() and chan_send() handle I/O to the kernel module and are hooked
- * up into a fuse-channel.
- */
-
-static int chan_receive(struct fuse_chan **chp, char *buf, size_t size)
-{
- struct fuse_chan *ch = *chp;
- struct kmscon_cdev *cdev = fuse_chan_data(ch);
- struct fuse_session *se = fuse_chan_session(ch);
- int fd = fuse_chan_fd(ch);
- ssize_t res;
-
- if (!se || !cdev)
- return -EINVAL;
-
- if (!size)
- return 0;
-
-restart:
- if (fuse_session_exited(se))
- return 0;
-
- res = read(fd, buf, size);
- if (!res) {
- /* EOF on cuse file */
- log_error("fuse channel shut down");
- fuse_session_exit(se);
- return 0;
- } else if (res < 0) {
- /* ENOENT is returned if the operation was interrupted, it's
- * safe to restart */
- if (errno == ENOENT)
- goto restart;
-
- /* ENODEV is returned if the FS got unmounted. This shouldn't
- * occur for CUSE devices. Anyway, exit if this happens. */
- if (errno == ENODEV) {
- fuse_session_exit(se);
- return 0;
- }
-
- /* EINTR and EAGAIN are simply forwarded to the caller. */
- if (errno == EINTR || errno == EAGAIN)
- return -errno;
-
- cdev->error = -errno;
- log_error("fuse channel read error (%d): %m", errno);
- fuse_session_exit(se);
- return cdev->error;
- }
-
- return res;
-}
-
-static int chan_send(struct fuse_chan *ch, const struct iovec iov[],
- size_t count)
-{
- struct kmscon_cdev *cdev = fuse_chan_data(ch);
- struct fuse_session *se = fuse_chan_session(ch);
- int fd = fuse_chan_fd(ch);
- int ret;
-
- if (!cdev || !se)
- return -EINVAL;
- if (!iov || !count)
- return 0;
-
- ret = writev(fd, iov, count);
- if (ret < 0) {
- /* ENOENT is returned on interruptions */
- if (!fuse_session_exited(se) && errno != ENOENT) {
- cdev->error = -errno;
- log_error("cannot write to fuse-channel (%d): %m",
- errno);
- fuse_session_exit(se);
- }
- return cdev->error;
- }
-
- return 0;
-}
-
-static const struct fuse_chan_ops chan_ops = {
- .receive = chan_receive,
- .send = chan_send,
- .destroy = NULL,
-};
-
-/*
- * Character Device
- * This creates the high-level character-device driver and registers a
- * fake-session that is used to control each fake-VT session.
- * channel_event() is a callback when I/O is possible on the FUSE FD and
- * performs all outstanding tasks.
- * On error, the fake-session is unregistered and deleted which also destroys
- * _all_ client fake-sessions.
- */
-
-static void channel_event(struct ev_fd *fd, int mask, void *data)
-{
- struct kmscon_cdev *cdev = data;
- int ret;
- struct fuse_buf buf;
- struct fuse_chan *ch;
- struct shl_dlist *i;
- struct cdev_client *client;
-
- if (mask & (EV_HUP | EV_ERR)) {
- log_error("HUP/ERR on fuse channel");
- cdev->error = -EPIPE;
- kmscon_session_unregister(cdev->s);
- return;
- }
-
- if (!(mask & EV_READABLE))
- return;
-
- memset(&buf, 0, sizeof(buf));
- buf.mem = cdev->buf;
- buf.size = cdev->bufsize;
- ch = cdev->channel;
- ret = fuse_session_receive_buf(cdev->session, &buf, &ch);
- if (ret == -EINTR || ret == -EAGAIN) {
- return;
- } else if (ret < 0) {
- log_error("fuse channel read error: %d", ret);
- cdev->error = ret;
- kmscon_session_unregister(cdev->s);
- return;
- }
-
- fuse_session_process_buf(cdev->session, &buf, ch);
- if (fuse_session_exited(cdev->session)) {
- log_error("fuse session exited");
- if (!cdev->error)
- cdev->error = -EFAULT;
- kmscon_session_unregister(cdev->s);
- return;
- }
-
- /* Readers can get interrupted asynchronously. Due to heavy locking
- * inside of FUSE, we cannot release them right away. So cleanup all
- * killed readers after we processed all buffers. */
- shl_dlist_for_each(i, &cdev->clients) {
- client = shl_dlist_entry(i, struct cdev_client, list);
- client_cleanup(client);
- }
-}
-
-static int kmscon_cdev_init(struct kmscon_cdev *cdev)
-{
- static const char prefix[] = "DEVNAME=";
- static const char fname[] = "/dev/cuse";
- int ret, id;
- size_t bufsize;
- struct cuse_info ci;
- const char *dev_info_argv[1];
- char *name;
-
- /* TODO: libfuse makes sure that fd 0, 1 and 2 are available as standard
- * streams, otherwise they fail. This is awkward and we should check
- * whether this is really needed and _why_?
- * If it is needed, fix upstream to stop that crazy! */
-
- shl_dlist_init(&cdev->clients);
-
- ret = asprintf(&name, "%sttyF%s", prefix,
- kmscon_seat_get_name(cdev->seat));
- if (ret <= 0) {
- log_error("cannot allocate memory for fuse-devname");
- return -ENOMEM;
- }
-
- log_info("initializing fake VT TTY device /dev/%s",
- &name[sizeof(prefix) - 1]);
-
- id = cdev_allocate_id();
- if (id < 0) {
- log_error("cannot allocate new cdev TTY id: %d", id);
- free(name);
- return id;
- }
- cdev->minor = id;
-
- dev_info_argv[0] = name;
- memset(&ci, 0, sizeof(ci));
- ci.dev_major = TTY_MAJOR;
- ci.dev_minor = cdev->minor;
- ci.dev_info_argc = 1;
- ci.dev_info_argv = dev_info_argv;
- ci.flags = CUSE_UNRESTRICTED_IOCTL;
-
- cdev->session = cuse_lowlevel_new(NULL, &ci, &ll_ops, cdev);
- free(name);
-
- if (!cdev->session) {
- log_error("cannot create fuse-ll session");
- return -ENOMEM;
- }
-
- cdev->fd = open(fname, O_RDWR | O_CLOEXEC);
- if (cdev->fd < 0) {
- log_error("cannot open %s (%d): %m", fname, errno);
- ret = -EFAULT;
- goto err_session;
- }
-
- bufsize = getpagesize() + 0x1000;
- if (bufsize < 0x21000)
- bufsize = 0x21000;
-
- cdev->bufsize = bufsize;
- cdev->buf = malloc(bufsize);
- if (!cdev->buf) {
- log_error("cannot allocate memory for buffer of size %zu",
- bufsize);
- ret = -ENOMEM;
- goto err_fd;
- }
-
- /* Argh! libfuse does not use "const" for the "chan_ops" pointer so we
- * actually have to cast it. Their implementation does not write into it
- * so we can safely use a constant storage for it.
- * TODO: Fix libfuse upstream! */
- cdev->channel = fuse_chan_new((void*)&chan_ops, cdev->fd, bufsize,
- cdev);
- if (!cdev->channel) {
- log_error("cannot allocate fuse-channel");
- ret = -ENOMEM;
- goto err_buf;
- }
-
- ret = ev_eloop_new_fd(cdev->eloop, &cdev->efd, cdev->fd, EV_READABLE,
- channel_event, cdev);
- if (ret) {
- log_error("cannot create fd-object in eloop: %d", ret);
- goto err_chan;
- }
-
- fuse_session_add_chan(cdev->session, cdev->channel);
- return 0;
-
-err_chan:
- fuse_chan_destroy(cdev->channel);
-err_buf:
- free(cdev->buf);
-err_fd:
- close(cdev->fd);
-err_session:
- fuse_session_destroy(cdev->session);
- return ret;
-}
-
-void kmscon_cdev_destroy(struct kmscon_cdev *cdev)
-{
- if (!cdev)
- return;
-
- if (cdev->error)
- log_warning("cdev module failed with error %d (maybe another kmscon process is already running?)",
- cdev->error);
-
- fuse_session_destroy(cdev->session);
- ev_eloop_rm_fd(cdev->efd);
- free(cdev->buf);
- close(cdev->fd);
-}
-
-static int session_event(struct kmscon_session *session,
- struct kmscon_session_event *ev, void *data)
-{
- struct kmscon_cdev *cdev = data;
-
- switch (ev->type) {
- case KMSCON_SESSION_UNREGISTER:
- log_debug("destroy cdev session");
- kmscon_cdev_destroy(cdev);
- free(cdev);
- break;
- }
-
- return 0;
-}
-
-int kmscon_cdev_register(struct kmscon_session **out,
- struct kmscon_seat *seat)
-{
- struct kmscon_cdev *cdev;
- int ret;
-
- if (!out || !seat)
- return -EINVAL;
-
- cdev = malloc(sizeof(*cdev));
- if (!cdev)
- return -ENOMEM;
- memset(cdev, 0, sizeof(*cdev));
- cdev->seat = seat;
- cdev->eloop = kmscon_seat_get_eloop(seat);
- cdev->input = kmscon_seat_get_input(seat);
-
- ret = kmscon_cdev_init(cdev);
- if (ret)
- goto err_free;
-
- ret = kmscon_seat_register_session(seat, &cdev->s, session_event, cdev);
- if (ret) {
- log_error("cannot register session for cdev: %d", ret);
- goto err_cdev;
- }
-
- *out = cdev->s;
- return 0;
-
-err_cdev:
- kmscon_cdev_destroy(cdev);
-err_free:
- free(cdev);
- return ret;
-}
projects / platform / upstream / kmscon.git / commitdiff