1dbddf429SAlex Dewar // SPDX-License-Identifier: GPL-2.0 21da177e4SLinus Torvalds /* 363920f47SJeff Dike * Copyright (C) 2001 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com) 41da177e4SLinus Torvalds */ 51da177e4SLinus Torvalds 663920f47SJeff Dike #include <linux/slab.h> 763920f47SJeff Dike #include <linux/completion.h> 863920f47SJeff Dike #include <linux/irqreturn.h> 963920f47SJeff Dike #include <asm/irq.h> 1037185b33SAl Viro #include <irq_kern.h> 1137185b33SAl Viro #include <os.h> 12*ab7ca2ebSNick Desaulniers #include "xterm.h" 131da177e4SLinus Torvalds 141da177e4SLinus Torvalds struct xterm_wait { 151da177e4SLinus Torvalds struct completion ready; 161da177e4SLinus Torvalds int fd; 171da177e4SLinus Torvalds int pid; 181da177e4SLinus Torvalds int new_fd; 191da177e4SLinus Torvalds }; 201da177e4SLinus Torvalds 217bea96fdSAl Viro static irqreturn_t xterm_interrupt(int irq, void *data) 221da177e4SLinus Torvalds { 231da177e4SLinus Torvalds struct xterm_wait *xterm = data; 241da177e4SLinus Torvalds int fd; 251da177e4SLinus Torvalds 261da177e4SLinus Torvalds fd = os_rcv_fd(xterm->fd, &xterm->pid); 271da177e4SLinus Torvalds if (fd == -EAGAIN) 2863920f47SJeff Dike return IRQ_NONE; 291da177e4SLinus Torvalds 301da177e4SLinus Torvalds xterm->new_fd = fd; 311da177e4SLinus Torvalds complete(&xterm->ready); 3263920f47SJeff Dike 3363920f47SJeff Dike return IRQ_HANDLED; 341da177e4SLinus Torvalds } 351da177e4SLinus Torvalds 361da177e4SLinus Torvalds int xterm_fd(int socket, int *pid_out) 371da177e4SLinus Torvalds { 381da177e4SLinus Torvalds struct xterm_wait *data; 391da177e4SLinus Torvalds int err, ret; 401da177e4SLinus Torvalds 411da177e4SLinus Torvalds data = kmalloc(sizeof(*data), GFP_KERNEL); 421da177e4SLinus Torvalds if (data == NULL) { 431da177e4SLinus Torvalds printk(KERN_ERR "xterm_fd : failed to allocate xterm_wait\n"); 4463920f47SJeff Dike return -ENOMEM; 451da177e4SLinus Torvalds } 461da177e4SLinus Torvalds 471da177e4SLinus Torvalds /* This is a locked semaphore... */ 4863920f47SJeff Dike *data = ((struct xterm_wait) { .fd = socket, 491da177e4SLinus Torvalds .pid = -1, 501da177e4SLinus Torvalds .new_fd = -1 }); 511da177e4SLinus Torvalds init_completion(&data->ready); 521da177e4SLinus Torvalds 531da177e4SLinus Torvalds err = um_request_irq(XTERM_IRQ, socket, IRQ_READ, xterm_interrupt, 54aab94460STheodore Ts'o IRQF_SHARED, "xterm", data); 5536d46a59SJohannes Berg if (err < 0) { 561da177e4SLinus Torvalds printk(KERN_ERR "xterm_fd : failed to get IRQ for xterm, " 571da177e4SLinus Torvalds "err = %d\n", err); 581da177e4SLinus Torvalds ret = err; 591da177e4SLinus Torvalds goto out; 601da177e4SLinus Torvalds } 611da177e4SLinus Torvalds 621da177e4SLinus Torvalds /* ... so here we wait for an xterm interrupt. 631da177e4SLinus Torvalds * 641da177e4SLinus Torvalds * XXX Note, if the xterm doesn't work for some reason (eg. DISPLAY 651da177e4SLinus Torvalds * isn't set) this will hang... */ 661da177e4SLinus Torvalds wait_for_completion(&data->ready); 671da177e4SLinus Torvalds 68fa7a0449SRichard Weinberger um_free_irq(XTERM_IRQ, data); 691da177e4SLinus Torvalds 701da177e4SLinus Torvalds ret = data->new_fd; 711da177e4SLinus Torvalds *pid_out = data->pid; 721da177e4SLinus Torvalds out: 731da177e4SLinus Torvalds kfree(data); 741da177e4SLinus Torvalds 7563920f47SJeff Dike return ret; 761da177e4SLinus Torvalds } 77