diff options
Diffstat (limited to 'arch/um/drivers/chan_user.c')
| -rw-r--r-- | arch/um/drivers/chan_user.c | 298 |
1 files changed, 191 insertions, 107 deletions
diff --git a/arch/um/drivers/chan_user.c b/arch/um/drivers/chan_user.c index 2f880cb167a..3fd7c3efdb1 100644 --- a/arch/um/drivers/chan_user.c +++ b/arch/um/drivers/chan_user.c @@ -1,70 +1,135 @@ -/* - * Copyright (C) 2000 - 2003 Jeff Dike (jdike@addtoit.com) +/* + * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{linux.intel,addtoit}.com) * Licensed under the GPL */ -#include <unistd.h> #include <stdlib.h> +#include <unistd.h> #include <errno.h> -#include <termios.h> -#include <string.h> -#include <signal.h> #include <sched.h> -#include <sys/stat.h> +#include <signal.h> +#include <termios.h> #include <sys/ioctl.h> -#include <sys/socket.h> -#include "kern_util.h" -#include "user_util.h" #include "chan_user.h" -#include "user.h" -#include "os.h" -#include "choose-mode.h" -#include "mode.h" +#include <os.h> +#include <um_malloc.h> + +void generic_close(int fd, void *unused) +{ + close(fd); +} + +int generic_read(int fd, char *c_out, void *unused) +{ + int n; + + n = read(fd, c_out, sizeof(*c_out)); + if (n > 0) + return n; + else if (errno == EAGAIN) + return 0; + else if (n == 0) + return -EIO; + return -errno; +} + +/* XXX Trivial wrapper around write */ + +int generic_write(int fd, const char *buf, int n, void *unused) +{ + int err; + + err = write(fd, buf, n); + if (err > 0) + return err; + else if (errno == EAGAIN) + return 0; + else if (err == 0) + return -EIO; + return -errno; +} + +int generic_window_size(int fd, void *unused, unsigned short *rows_out, + unsigned short *cols_out) +{ + struct winsize size; + int ret; + + if (ioctl(fd, TIOCGWINSZ, &size) < 0) + return -errno; + + ret = ((*rows_out != size.ws_row) || (*cols_out != size.ws_col)); + + *rows_out = size.ws_row; + *cols_out = size.ws_col; + + return ret; +} + +void generic_free(void *data) +{ + kfree(data); +} int generic_console_write(int fd, const char *buf, int n) { + sigset_t old, no_sigio; struct termios save, new; int err; - if(isatty(fd)){ + if (isatty(fd)) { + sigemptyset(&no_sigio); + sigaddset(&no_sigio, SIGIO); + if (sigprocmask(SIG_BLOCK, &no_sigio, &old)) + goto error; + CATCH_EINTR(err = tcgetattr(fd, &save)); if (err) goto error; new = save; - /* The terminal becomes a bit less raw, to handle \n also as + /* + * The terminal becomes a bit less raw, to handle \n also as * "Carriage Return", not only as "New Line". Otherwise, the new - * line won't start at the first column.*/ + * line won't start at the first column. + */ new.c_oflag |= OPOST; CATCH_EINTR(err = tcsetattr(fd, TCSAFLUSH, &new)); if (err) goto error; } err = generic_write(fd, buf, n, NULL); - /* Restore raw mode, in any case; we *must* ignore any error apart - * EINTR, except for debug.*/ - if(isatty(fd)) + /* + * Restore raw mode, in any case; we *must* ignore any error apart + * EINTR, except for debug. + */ + if (isatty(fd)) { CATCH_EINTR(tcsetattr(fd, TCSAFLUSH, &save)); - return(err); + sigprocmask(SIG_SETMASK, &old, NULL); + } + + return err; error: - return(-errno); + return -errno; } /* * UML SIGWINCH handling * - * The point of this is to handle SIGWINCH on consoles which have host ttys and - * relay them inside UML to whatever might be running on the console and cares - * about the window size (since SIGWINCH notifies about terminal size changes). + * The point of this is to handle SIGWINCH on consoles which have host + * ttys and relay them inside UML to whatever might be running on the + * console and cares about the window size (since SIGWINCH notifies + * about terminal size changes). * - * So, we have a separate thread for each host tty attached to a UML device - * (side-issue - I'm annoyed that one thread can't have multiple controlling - * ttys for purposed of handling SIGWINCH, but I imagine there are other reasons - * that doesn't make any sense). + * So, we have a separate thread for each host tty attached to a UML + * device (side-issue - I'm annoyed that one thread can't have + * multiple controlling ttys for the purpose of handling SIGWINCH, but + * I imagine there are other reasons that doesn't make any sense). * - * SIGWINCH can't be received synchronously, so you have to set up to receive it - * as a signal. That being the case, if you are going to wait for it, it is - * convenient to sit in sigsuspend() and wait for the signal to bounce you out of - * it (see below for how we make sure to exit only on SIGWINCH). + * SIGWINCH can't be received synchronously, so you have to set up to + * receive it as a signal. That being the case, if you are going to + * wait for it, it is convenient to sit in sigsuspend() and wait for + * the signal to bounce you out of it (see below for how we make sure + * to exit only on SIGWINCH). */ static void winch_handler(int sig) @@ -81,137 +146,156 @@ static int winch_thread(void *arg) struct winch_data *data = arg; sigset_t sigs; int pty_fd, pipe_fd; - int count, err; + int count; char c = 1; pty_fd = data->pty_fd; pipe_fd = data->pipe_fd; - count = os_write_file(pipe_fd, &c, sizeof(c)); - if(count != sizeof(c)) - printk("winch_thread : failed to write synchronization " - "byte, err = %d\n", -count); + count = write(pipe_fd, &c, sizeof(c)); + if (count != sizeof(c)) + printk(UM_KERN_ERR "winch_thread : failed to write " + "synchronization byte, err = %d\n", -count); - /* We are not using SIG_IGN on purpose, so don't fix it as I thought to + /* + * We are not using SIG_IGN on purpose, so don't fix it as I thought to * do! If using SIG_IGN, the sigsuspend() call below would not stop on - * SIGWINCH. */ + * SIGWINCH. + */ signal(SIGWINCH, winch_handler); sigfillset(&sigs); /* Block all signals possible. */ - if(sigprocmask(SIG_SETMASK, &sigs, NULL) < 0){ - printk("winch_thread : sigprocmask failed, errno = %d\n", - errno); + if (sigprocmask(SIG_SETMASK, &sigs, NULL) < 0) { + printk(UM_KERN_ERR "winch_thread : sigprocmask failed, " + "errno = %d\n", errno); exit(1); } /* In sigsuspend(), block anything else than SIGWINCH. */ sigdelset(&sigs, SIGWINCH); - if(setsid() < 0){ - printk("winch_thread : setsid failed, errno = %d\n", errno); + if (setsid() < 0) { + printk(UM_KERN_ERR "winch_thread : setsid failed, errno = %d\n", + errno); + exit(1); + } + + if (ioctl(pty_fd, TIOCSCTTY, 0) < 0) { + printk(UM_KERN_ERR "winch_thread : TIOCSCTTY failed on " + "fd %d err = %d\n", pty_fd, errno); exit(1); } - err = os_new_tty_pgrp(pty_fd, os_getpid()); - if(err < 0){ - printk("winch_thread : new_tty_pgrp failed, err = %d\n", -err); + if (tcsetpgrp(pty_fd, os_getpid()) < 0) { + printk(UM_KERN_ERR "winch_thread : tcsetpgrp failed on " + "fd %d err = %d\n", pty_fd, errno); exit(1); } - /* These are synchronization calls between various UML threads on the + /* + * These are synchronization calls between various UML threads on the * host - since they are not different kernel threads, we cannot use * kernel semaphores. We don't use SysV semaphores because they are - * persistant. */ - count = os_read_file(pipe_fd, &c, sizeof(c)); - if(count != sizeof(c)) - printk("winch_thread : failed to read synchronization byte, " - "err = %d\n", -count); - - while(1){ - /* This will be interrupted by SIGWINCH only, since other signals - * are blocked.*/ + * persistent. + */ + count = read(pipe_fd, &c, sizeof(c)); + if (count != sizeof(c)) + printk(UM_KERN_ERR "winch_thread : failed to read " + "synchronization byte, err = %d\n", errno); + + while(1) { + /* + * This will be interrupted by SIGWINCH only, since + * other signals are blocked. + */ sigsuspend(&sigs); - count = os_write_file(pipe_fd, &c, sizeof(c)); - if(count != sizeof(c)) - printk("winch_thread : write failed, err = %d\n", - -count); + count = write(pipe_fd, &c, sizeof(c)); + if (count != sizeof(c)) + printk(UM_KERN_ERR "winch_thread : write failed, " + "err = %d\n", errno); } } -static int winch_tramp(int fd, struct tty_struct *tty, int *fd_out) +static int winch_tramp(int fd, struct tty_port *port, int *fd_out, + unsigned long *stack_out) { struct winch_data data; - unsigned long stack; int fds[2], n, err; char c; err = os_pipe(fds, 1, 1); - if(err < 0){ - printk("winch_tramp : os_pipe failed, err = %d\n", -err); + if (err < 0) { + printk(UM_KERN_ERR "winch_tramp : os_pipe failed, err = %d\n", + -err); goto out; } data = ((struct winch_data) { .pty_fd = fd, .pipe_fd = fds[1] } ); - /* CLONE_FILES so this thread doesn't hold open files which are open - * now, but later closed. This is a problem with /dev/net/tun. + /* + * CLONE_FILES so this thread doesn't hold open files which are open + * now, but later closed in a different thread. This is a + * problem with /dev/net/tun, which if held open by this + * thread, prevents the TUN/TAP device from being reused. */ - err = run_helper_thread(winch_thread, &data, CLONE_FILES, &stack, 0); - if(err < 0){ - printk("fork of winch_thread failed - errno = %d\n", errno); + err = run_helper_thread(winch_thread, &data, CLONE_FILES, stack_out); + if (err < 0) { + printk(UM_KERN_ERR "fork of winch_thread failed - errno = %d\n", + -err); goto out_close; } *fd_out = fds[0]; - n = os_read_file(fds[0], &c, sizeof(c)); - if(n != sizeof(c)){ - printk("winch_tramp : failed to read synchronization byte\n"); - printk("read failed, err = %d\n", -n); - printk("fd %d will not support SIGWINCH\n", fd); - err = -EINVAL; + n = read(fds[0], &c, sizeof(c)); + if (n != sizeof(c)) { + printk(UM_KERN_ERR "winch_tramp : failed to read " + "synchronization byte\n"); + printk(UM_KERN_ERR "read failed, err = %d\n", errno); + printk(UM_KERN_ERR "fd %d will not support SIGWINCH\n", fd); + err = -EINVAL; goto out_close; } - return err ; + + if (os_set_fd_block(*fd_out, 0)) { + printk(UM_KERN_ERR "winch_tramp: failed to set thread_fd " + "non-blocking.\n"); + goto out_close; + } + + return err; out_close: - os_close_file(fds[1]); - os_close_file(fds[0]); + close(fds[1]); + close(fds[0]); out: return err; } -void register_winch(int fd, struct tty_struct *tty) +void register_winch(int fd, struct tty_port *port) { - int pid, thread, thread_fd = -1; - int count; + unsigned long stack; + int pid, thread, count, thread_fd = -1; char c = 1; - if(!isatty(fd)) + if (!isatty(fd)) return; pid = tcgetpgrp(fd); - if(!CHOOSE_MODE_PROC(is_tracer_winch, is_skas_winch, pid, fd, - tty) && (pid == -1)){ - thread = winch_tramp(fd, tty, &thread_fd); - if(thread > 0){ - register_winch_irq(thread_fd, fd, thread, tty); - - count = os_write_file(thread_fd, &c, sizeof(c)); - if(count != sizeof(c)) - printk("register_winch : failed to write " - "synchronization byte, err = %d\n", - -count); - } + if (is_skas_winch(pid, fd, port)) { + register_winch_irq(-1, fd, -1, port, 0); + return; } -} -/* - * Overrides for Emacs so that we follow Linus's tabbing style. - * Emacs will notice this stuff at the end of the file and automatically - * adjust the settings for this buffer only. This must remain at the end - * of the file. - * --------------------------------------------------------------------------- - * Local variables: - * c-file-style: "linux" - * End: - */ + if (pid == -1) { + thread = winch_tramp(fd, port, &thread_fd, &stack); + if (thread < 0) + return; + + register_winch_irq(thread_fd, fd, thread, port, stack); + + count = write(thread_fd, &c, sizeof(c)); + if (count != sizeof(c)) + printk(UM_KERN_ERR "register_winch : failed to write " + "synchronization byte, err = %d\n", errno); + } +} |
