/*
- * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
+ * Copyright (C) 2002 - 2008 Jeff Dike (jdike@{addtoit,linux.intel}.com)
* Licensed under the GPL
*/
#include <unistd.h>
-#include <stdlib.h>
-#include <termios.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <poll.h>
#include <pty.h>
+#include <sched.h>
#include <signal.h>
-#include <errno.h>
#include <string.h>
-#include <sched.h>
-#include <sys/socket.h>
-#include <sys/poll.h>
-#include "init.h"
-#include "user.h"
+#include "kern_constants.h"
#include "kern_util.h"
-#include "user_util.h"
-#include "sigio.h"
+#include "init.h"
#include "os.h"
+#include "process.h"
+#include "sigio.h"
+#include "um_malloc.h"
+#include "user.h"
-/* Protected by sigio_lock(), also used by sigio_cleanup, which is an
+/*
+ * Protected by sigio_lock(), also used by sigio_cleanup, which is an
* exitcall.
*/
static int write_sigio_pid = -1;
+static unsigned long write_sigio_stack;
-/* These arrays are initialized before the sigio thread is started, and
+/*
+ * These arrays are initialized before the sigio thread is started, and
* the descriptors closed after it is killed. So, it can't see them change.
* On the UML side, they are changed under the sigio_lock.
*/
int used;
};
-/* Protected by sigio_lock(). Used by the sigio thread, but the UML thread
+/*
+ * Protected by sigio_lock(). Used by the sigio thread, but the UML thread
* synchronizes with it.
*/
-static struct pollfds current_poll = {
- .poll = NULL,
- .size = 0,
- .used = 0
-};
-
-static struct pollfds next_poll = {
- .poll = NULL,
- .size = 0,
- .used = 0
-};
+static struct pollfds current_poll;
+static struct pollfds next_poll;
+static struct pollfds all_sigio_fds;
static int write_sigio_thread(void *unused)
{
int i, n, respond_fd;
char c;
- signal(SIGWINCH, SIG_IGN);
+ signal(SIGWINCH, SIG_IGN);
fds = ¤t_poll;
- while(1){
+ while (1) {
n = poll(fds->poll, fds->used, -1);
- if(n < 0){
- if(errno == EINTR) continue;
- printk("write_sigio_thread : poll returned %d, "
- "errno = %d\n", n, errno);
+ if (n < 0) {
+ if (errno == EINTR)
+ continue;
+ printk(UM_KERN_ERR "write_sigio_thread : poll returned "
+ "%d, errno = %d\n", n, errno);
}
- for(i = 0; i < fds->used; i++){
+ for (i = 0; i < fds->used; i++) {
p = &fds->poll[i];
- if(p->revents == 0) continue;
- if(p->fd == sigio_private[1]){
- n = os_read_file(sigio_private[1], &c, sizeof(c));
- if(n != sizeof(c))
- printk("write_sigio_thread : "
- "read failed, err = %d\n", -n);
+ if (p->revents == 0)
+ continue;
+ if (p->fd == sigio_private[1]) {
+ CATCH_EINTR(n = read(sigio_private[1], &c,
+ sizeof(c)));
+ if (n != sizeof(c))
+ printk(UM_KERN_ERR
+ "write_sigio_thread : "
+ "read on socket failed, "
+ "err = %d\n", errno);
tmp = current_poll;
current_poll = next_poll;
next_poll = tmp;
(fds->used - i) * sizeof(*fds->poll));
}
- n = os_write_file(respond_fd, &c, sizeof(c));
- if(n != sizeof(c))
- printk("write_sigio_thread : write failed, "
- "err = %d\n", -n);
+ CATCH_EINTR(n = write(respond_fd, &c, sizeof(c)));
+ if (n != sizeof(c))
+ printk(UM_KERN_ERR "write_sigio_thread : "
+ "write on socket failed, err = %d\n",
+ errno);
}
}
return 0;
}
-static int need_poll(int n)
+static int need_poll(struct pollfds *polls, int n)
{
- if(n <= next_poll.size){
- next_poll.used = n;
- return(0);
- }
- kfree(next_poll.poll);
- next_poll.poll = um_kmalloc_atomic(n * sizeof(struct pollfd));
- if(next_poll.poll == NULL){
- printk("need_poll : failed to allocate new pollfds\n");
- next_poll.size = 0;
- next_poll.used = 0;
- return(-1);
+ struct pollfd *new;
+
+ if (n <= polls->size)
+ return 0;
+
+ new = uml_kmalloc(n * sizeof(struct pollfd), UM_GFP_ATOMIC);
+ if (new == NULL) {
+ printk(UM_KERN_ERR "need_poll : failed to allocate new "
+ "pollfds\n");
+ return -ENOMEM;
}
- next_poll.size = n;
- next_poll.used = n;
- return(0);
+
+ memcpy(new, polls->poll, polls->used * sizeof(struct pollfd));
+ kfree(polls->poll);
+
+ polls->poll = new;
+ polls->size = n;
+ return 0;
}
-/* Must be called with sigio_lock held, because it's needed by the marked
- * critical section. */
+/*
+ * Must be called with sigio_lock held, because it's needed by the marked
+ * critical section.
+ */
static void update_thread(void)
{
unsigned long flags;
char c;
flags = set_signals(0);
- n = os_write_file(sigio_private[0], &c, sizeof(c));
- if(n != sizeof(c)){
- printk("update_thread : write failed, err = %d\n", -n);
+ CATCH_EINTR(n = write(sigio_private[0], &c, sizeof(c)));
+ if (n != sizeof(c)) {
+ printk(UM_KERN_ERR "update_thread : write failed, err = %d\n",
+ errno);
goto fail;
}
- n = os_read_file(sigio_private[0], &c, sizeof(c));
- if(n != sizeof(c)){
- printk("update_thread : read failed, err = %d\n", -n);
+ CATCH_EINTR(n = read(sigio_private[0], &c, sizeof(c)));
+ if (n != sizeof(c)) {
+ printk(UM_KERN_ERR "update_thread : read failed, err = %d\n",
+ errno);
goto fail;
}
return;
fail:
/* Critical section start */
- if(write_sigio_pid != -1)
+ if (write_sigio_pid != -1) {
os_kill_process(write_sigio_pid, 1);
+ free_stack(write_sigio_stack, 0);
+ }
write_sigio_pid = -1;
close(sigio_private[0]);
close(sigio_private[1]);
set_signals(flags);
}
-static int add_sigio_fd(int fd, int read)
+int add_sigio_fd(int fd)
{
- int err = 0, i, n, events;
+ struct pollfd *p;
+ int err = 0, i, n;
sigio_lock();
- for(i = 0; i < current_poll.used; i++){
- if(current_poll.poll[i].fd == fd)
- goto out;
+ for (i = 0; i < all_sigio_fds.used; i++) {
+ if (all_sigio_fds.poll[i].fd == fd)
+ break;
}
-
- n = current_poll.used + 1;
- err = need_poll(n);
- if(err)
+ if (i == all_sigio_fds.used)
goto out;
- for(i = 0; i < current_poll.used; i++)
- next_poll.poll[i] = current_poll.poll[i];
+ p = &all_sigio_fds.poll[i];
- if(read) events = POLLIN;
- else events = POLLOUT;
+ for (i = 0; i < current_poll.used; i++) {
+ if (current_poll.poll[i].fd == fd)
+ goto out;
+ }
+
+ n = current_poll.used;
+ err = need_poll(&next_poll, n + 1);
+ if (err)
+ goto out;
- next_poll.poll[n - 1] = ((struct pollfd) { .fd = fd,
- .events = events,
- .revents = 0 });
+ memcpy(next_poll.poll, current_poll.poll,
+ current_poll.used * sizeof(struct pollfd));
+ next_poll.poll[n] = *p;
+ next_poll.used = n + 1;
update_thread();
out:
sigio_unlock();
- return(err);
+ return err;
}
int ignore_sigio_fd(int fd)
struct pollfd *p;
int err = 0, i, n = 0;
- /* This is called from exitcalls elsewhere in UML - if
+ /*
+ * This is called from exitcalls elsewhere in UML - if
* sigio_cleanup has already run, then update_thread will hang
* or fail because the thread is no longer running.
*/
- if(write_sigio_pid == -1)
+ if (write_sigio_pid == -1)
return -EIO;
sigio_lock();
- for(i = 0; i < current_poll.used; i++){
- if(current_poll.poll[i].fd == fd) break;
+ for (i = 0; i < current_poll.used; i++) {
+ if (current_poll.poll[i].fd == fd)
+ break;
}
- if(i == current_poll.used)
+ if (i == current_poll.used)
goto out;
- err = need_poll(current_poll.used - 1);
- if(err)
+ err = need_poll(&next_poll, current_poll.used - 1);
+ if (err)
goto out;
- for(i = 0; i < current_poll.used; i++){
+ for (i = 0; i < current_poll.used; i++) {
p = ¤t_poll.poll[i];
- if(p->fd != fd) next_poll.poll[n++] = current_poll.poll[i];
- }
- if(n == i){
- printk("ignore_sigio_fd : fd %d not found\n", fd);
- err = -1;
- goto out;
+ if (p->fd != fd)
+ next_poll.poll[n++] = *p;
}
+ next_poll.used = current_poll.used - 1;
update_thread();
out:
{
struct pollfd *p;
- p = um_kmalloc(sizeof(struct pollfd));
+ p = uml_kmalloc(sizeof(struct pollfd), UM_GFP_KERNEL);
if (p == NULL) {
- printk("setup_initial_poll : failed to allocate poll\n");
+ printk(UM_KERN_ERR "setup_initial_poll : failed to allocate "
+ "poll\n");
return NULL;
}
- *p = ((struct pollfd) { .fd = fd,
+ *p = ((struct pollfd) { .fd = fd,
.events = POLLIN,
.revents = 0 });
return p;
static void write_sigio_workaround(void)
{
- unsigned long stack;
struct pollfd *p;
int err;
int l_write_sigio_fds[2];
return;
err = os_pipe(l_write_sigio_fds, 1, 1);
- if(err < 0){
- printk("write_sigio_workaround - os_pipe 1 failed, "
+ if (err < 0) {
+ printk(UM_KERN_ERR "write_sigio_workaround - os_pipe 1 failed, "
"err = %d\n", -err);
return;
}
err = os_pipe(l_sigio_private, 1, 1);
- if(err < 0){
- printk("write_sigio_workaround - os_pipe 2 failed, "
+ if (err < 0) {
+ printk(UM_KERN_ERR "write_sigio_workaround - os_pipe 2 failed, "
"err = %d\n", -err);
goto out_close1;
}
p = setup_initial_poll(l_sigio_private[1]);
- if(!p)
+ if (!p)
goto out_close2;
sigio_lock();
- /* Did we race? Don't try to optimize this, please, it's not so likely
- * to happen, and no more than once at the boot. */
- if(write_sigio_pid != -1)
+ /*
+ * Did we race? Don't try to optimize this, please, it's not so likely
+ * to happen, and no more than once at the boot.
+ */
+ if (write_sigio_pid != -1)
goto out_free;
current_poll = ((struct pollfds) { .poll = p,
memcpy(sigio_private, l_sigio_private, sizeof(l_sigio_private));
write_sigio_pid = run_helper_thread(write_sigio_thread, NULL,
- CLONE_FILES | CLONE_VM, &stack, 0);
+ CLONE_FILES | CLONE_VM,
+ &write_sigio_stack);
if (write_sigio_pid < 0)
goto out_clear;
close(l_write_sigio_fds[1]);
}
+void sigio_broken(int fd, int read)
+{
+ int err;
+
+ write_sigio_workaround();
+
+ sigio_lock();
+ err = need_poll(&all_sigio_fds, all_sigio_fds.used + 1);
+ if (err) {
+ printk(UM_KERN_ERR "maybe_sigio_broken - failed to add pollfd "
+ "for descriptor %d\n", fd);
+ goto out;
+ }
+
+ all_sigio_fds.poll[all_sigio_fds.used++] =
+ ((struct pollfd) { .fd = fd,
+ .events = read ? POLLIN : POLLOUT,
+ .revents = 0 });
+out:
+ sigio_unlock();
+}
+
+/* Changed during early boot */
+static int pty_output_sigio;
+static int pty_close_sigio;
+
void maybe_sigio_broken(int fd, int read)
{
- if(!isatty(fd))
+ if (!isatty(fd))
return;
- if((read || pty_output_sigio) && (!read || pty_close_sigio))
+ if ((read || pty_output_sigio) && (!read || pty_close_sigio))
return;
- write_sigio_workaround();
- add_sigio_fd(fd, read);
+ sigio_broken(fd, read);
}
static void sigio_cleanup(void)
{
- if(write_sigio_pid != -1){
- os_kill_process(write_sigio_pid, 1);
- write_sigio_pid = -1;
- }
+ if (write_sigio_pid == -1)
+ return;
+
+ os_kill_process(write_sigio_pid, 1);
+ free_stack(write_sigio_stack, 0);
+ write_sigio_pid = -1;
}
__uml_exitcall(sigio_cleanup);
+
+/* Used as a flag during SIGIO testing early in boot */
+static int got_sigio;
+
+static void __init handler(int sig)
+{
+ got_sigio = 1;
+}
+
+struct openpty_arg {
+ int master;
+ int slave;
+ int err;
+};
+
+static void openpty_cb(void *arg)
+{
+ struct openpty_arg *info = arg;
+
+ info->err = 0;
+ if (openpty(&info->master, &info->slave, NULL, NULL, NULL))
+ info->err = -errno;
+}
+
+static int async_pty(int master, int slave)
+{
+ int flags;
+
+ flags = fcntl(master, F_GETFL);
+ if (flags < 0)
+ return -errno;
+
+ if ((fcntl(master, F_SETFL, flags | O_NONBLOCK | O_ASYNC) < 0) ||
+ (fcntl(master, F_SETOWN, os_getpid()) < 0))
+ return -errno;
+
+ if ((fcntl(slave, F_SETFL, flags | O_NONBLOCK) < 0))
+ return -errno;
+
+ return 0;
+}
+
+static void __init check_one_sigio(void (*proc)(int, int))
+{
+ struct sigaction old, new;
+ struct openpty_arg pty = { .master = -1, .slave = -1 };
+ int master, slave, err;
+
+ initial_thread_cb(openpty_cb, &pty);
+ if (pty.err) {
+ printk(UM_KERN_ERR "check_one_sigio failed, errno = %d\n",
+ -pty.err);
+ return;
+ }
+
+ master = pty.master;
+ slave = pty.slave;
+
+ if ((master == -1) || (slave == -1)) {
+ printk(UM_KERN_ERR "check_one_sigio failed to allocate a "
+ "pty\n");
+ return;
+ }
+
+ /* Not now, but complain so we now where we failed. */
+ err = raw(master);
+ if (err < 0) {
+ printk(UM_KERN_ERR "check_one_sigio : raw failed, errno = %d\n",
+ -err);
+ return;
+ }
+
+ err = async_pty(master, slave);
+ if (err < 0) {
+ printk(UM_KERN_ERR "check_one_sigio : sigio_async failed, "
+ "err = %d\n", -err);
+ return;
+ }
+
+ if (sigaction(SIGIO, NULL, &old) < 0) {
+ printk(UM_KERN_ERR "check_one_sigio : sigaction 1 failed, "
+ "errno = %d\n", errno);
+ return;
+ }
+
+ new = old;
+ new.sa_handler = handler;
+ if (sigaction(SIGIO, &new, NULL) < 0) {
+ printk(UM_KERN_ERR "check_one_sigio : sigaction 2 failed, "
+ "errno = %d\n", errno);
+ return;
+ }
+
+ got_sigio = 0;
+ (*proc)(master, slave);
+
+ close(master);
+ close(slave);
+
+ if (sigaction(SIGIO, &old, NULL) < 0)
+ printk(UM_KERN_ERR "check_one_sigio : sigaction 3 failed, "
+ "errno = %d\n", errno);
+}
+
+static void tty_output(int master, int slave)
+{
+ int n;
+ char buf[512];
+
+ printk(UM_KERN_INFO "Checking that host ptys support output SIGIO...");
+
+ memset(buf, 0, sizeof(buf));
+
+ while (write(master, buf, sizeof(buf)) > 0) ;
+ if (errno != EAGAIN)
+ printk(UM_KERN_ERR "tty_output : write failed, errno = %d\n",
+ errno);
+ while (((n = read(slave, buf, sizeof(buf))) > 0) &&
+ !({ barrier(); got_sigio; }))
+ ;
+
+ if (got_sigio) {
+ printk(UM_KERN_CONT "Yes\n");
+ pty_output_sigio = 1;
+ } else if (n == -EAGAIN)
+ printk(UM_KERN_CONT "No, enabling workaround\n");
+ else
+ printk(UM_KERN_CONT "tty_output : read failed, err = %d\n", n);
+}
+
+static void tty_close(int master, int slave)
+{
+ printk(UM_KERN_INFO "Checking that host ptys support SIGIO on "
+ "close...");
+
+ close(slave);
+ if (got_sigio) {
+ printk(UM_KERN_CONT "Yes\n");
+ pty_close_sigio = 1;
+ } else
+ printk(UM_KERN_CONT "No, enabling workaround\n");
+}
+
+static void __init check_sigio(void)
+{
+ if ((access("/dev/ptmx", R_OK) < 0) &&
+ (access("/dev/ptyp0", R_OK) < 0)) {
+ printk(UM_KERN_WARNING "No pseudo-terminals available - "
+ "skipping pty SIGIO check\n");
+ return;
+ }
+ check_one_sigio(tty_output);
+ check_one_sigio(tty_close);
+}
+
+/* Here because it only does the SIGIO testing for now */
+void __init os_check_bugs(void)
+{
+ check_sigio();
+}
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff