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-rw-r--r--arch/um/kernel/sigio_user.c466
1 files changed, 0 insertions, 466 deletions
diff --git a/arch/um/kernel/sigio_user.c b/arch/um/kernel/sigio_user.c
deleted file mode 100644
index f7b18e1..0000000
--- a/arch/um/kernel/sigio_user.c
+++ /dev/null
@@ -1,466 +0,0 @@
-/*
- * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
- * Licensed under the GPL
- */
-
-#include <unistd.h>
-#include <stdlib.h>
-#include <termios.h>
-#include <pty.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_util.h"
-#include "user_util.h"
-#include "sigio.h"
-#include "os.h"
-
-/* Changed during early boot */
-int pty_output_sigio = 0;
-int pty_close_sigio = 0;
-
-/* Used as a flag during SIGIO testing early in boot */
-static volatile int got_sigio = 0;
-
-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;
-}
-
-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("openpty failed, errno = %d\n", -pty.err);
- return;
- }
-
- master = pty.master;
- slave = pty.slave;
-
- if((master == -1) || (slave == -1)){
- printk("openpty failed to allocate a pty\n");
- return;
- }
-
- /* Not now, but complain so we now where we failed. */
- err = raw(master);
- if (err < 0)
- panic("check_sigio : __raw failed, errno = %d\n", -err);
-
- err = os_sigio_async(master, slave);
- if(err < 0)
- panic("tty_fds : sigio_async failed, err = %d\n", -err);
-
- if(sigaction(SIGIO, NULL, &old) < 0)
- panic("check_sigio : sigaction 1 failed, errno = %d\n", errno);
- new = old;
- new.sa_handler = handler;
- if(sigaction(SIGIO, &new, NULL) < 0)
- panic("check_sigio : sigaction 2 failed, errno = %d\n", errno);
-
- got_sigio = 0;
- (*proc)(master, slave);
-
- os_close_file(master);
- os_close_file(slave);
-
- if(sigaction(SIGIO, &old, NULL) < 0)
- panic("check_sigio : sigaction 3 failed, errno = %d\n", errno);
-}
-
-static void tty_output(int master, int slave)
-{
- int n;
- char buf[512];
-
- printk("Checking that host ptys support output SIGIO...");
-
- memset(buf, 0, sizeof(buf));
-
- while(os_write_file(master, buf, sizeof(buf)) > 0) ;
- if(errno != EAGAIN)
- panic("check_sigio : write failed, errno = %d\n", errno);
- while(((n = os_read_file(slave, buf, sizeof(buf))) > 0) && !got_sigio) ;
-
- if (got_sigio) {
- printk("Yes\n");
- pty_output_sigio = 1;
- } else if (n == -EAGAIN) {
- printk("No, enabling workaround\n");
- } else {
- panic("check_sigio : read failed, err = %d\n", n);
- }
-}
-
-static void tty_close(int master, int slave)
-{
- printk("Checking that host ptys support SIGIO on close...");
-
- os_close_file(slave);
- if(got_sigio){
- printk("Yes\n");
- pty_close_sigio = 1;
- }
- else printk("No, enabling workaround\n");
-}
-
-void __init check_sigio(void)
-{
- if((os_access("/dev/ptmx", OS_ACC_R_OK) < 0) &&
- (os_access("/dev/ptyp0", OS_ACC_R_OK) < 0)){
- printk("No pseudo-terminals available - skipping pty SIGIO "
- "check\n");
- return;
- }
- check_one_sigio(tty_output);
- check_one_sigio(tty_close);
-}
-
-/* Protected by sigio_lock(), also used by sigio_cleanup, which is an
- * exitcall.
- */
-static int write_sigio_pid = -1;
-
-/* 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.
- */
-static int write_sigio_fds[2] = { -1, -1 };
-static int sigio_private[2] = { -1, -1 };
-
-struct pollfds {
- struct pollfd *poll;
- int size;
- int used;
-};
-
-/* Protected by sigio_lock(). Used by the sigio thread, but the UML thread
- * synchronizes with it.
- */
-struct pollfds current_poll = {
- .poll = NULL,
- .size = 0,
- .used = 0
-};
-
-struct pollfds next_poll = {
- .poll = NULL,
- .size = 0,
- .used = 0
-};
-
-static int write_sigio_thread(void *unused)
-{
- struct pollfds *fds, tmp;
- struct pollfd *p;
- int i, n, respond_fd;
- char c;
-
- signal(SIGWINCH, SIG_IGN);
- fds = &current_poll;
- 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);
- }
- 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);
- tmp = current_poll;
- current_poll = next_poll;
- next_poll = tmp;
- respond_fd = sigio_private[1];
- }
- else {
- respond_fd = write_sigio_fds[1];
- fds->used--;
- memmove(&fds->poll[i], &fds->poll[i + 1],
- (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);
- }
- }
-
- return 0;
-}
-
-static int need_poll(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);
- }
- next_poll.size = n;
- next_poll.used = n;
- return(0);
-}
-
-/* Must be called with sigio_lock held, because it's needed by the marked
- * critical section. */
-static void update_thread(void)
-{
- unsigned long flags;
- int n;
- 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);
- 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);
- goto fail;
- }
-
- set_signals(flags);
- return;
- fail:
- /* Critical section start */
- if(write_sigio_pid != -1)
- os_kill_process(write_sigio_pid, 1);
- write_sigio_pid = -1;
- os_close_file(sigio_private[0]);
- os_close_file(sigio_private[1]);
- os_close_file(write_sigio_fds[0]);
- os_close_file(write_sigio_fds[1]);
- /* Critical section end */
- set_signals(flags);
-}
-
-int add_sigio_fd(int fd, int read)
-{
- int err = 0, i, n, events;
-
- sigio_lock();
- for(i = 0; i < current_poll.used; i++){
- if(current_poll.poll[i].fd == fd)
- goto out;
- }
-
- n = current_poll.used + 1;
- err = need_poll(n);
- if(err)
- goto out;
-
- for(i = 0; i < current_poll.used; i++)
- next_poll.poll[i] = current_poll.poll[i];
-
- if(read) events = POLLIN;
- else events = POLLOUT;
-
- next_poll.poll[n - 1] = ((struct pollfd) { .fd = fd,
- .events = events,
- .revents = 0 });
- update_thread();
- out:
- sigio_unlock();
- return(err);
-}
-
-int ignore_sigio_fd(int fd)
-{
- struct pollfd *p;
- int err = 0, i, n = 0;
-
- sigio_lock();
- for(i = 0; i < current_poll.used; i++){
- if(current_poll.poll[i].fd == fd) break;
- }
- if(i == current_poll.used)
- goto out;
-
- err = need_poll(current_poll.used - 1);
- if(err)
- goto out;
-
- for(i = 0; i < current_poll.used; i++){
- p = &current_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;
- }
-
- update_thread();
- out:
- sigio_unlock();
- return(err);
-}
-
-static struct pollfd* setup_initial_poll(int fd)
-{
- struct pollfd *p;
-
- p = um_kmalloc(sizeof(struct pollfd));
- if (p == NULL) {
- printk("setup_initial_poll : failed to allocate poll\n");
- return NULL;
- }
- *p = ((struct pollfd) { .fd = fd,
- .events = POLLIN,
- .revents = 0 });
- return p;
-}
-
-void write_sigio_workaround(void)
-{
- unsigned long stack;
- struct pollfd *p;
- int err;
- int l_write_sigio_fds[2];
- int l_sigio_private[2];
- int l_write_sigio_pid;
-
- /* We call this *tons* of times - and most ones we must just fail. */
- sigio_lock();
- l_write_sigio_pid = write_sigio_pid;
- sigio_unlock();
-
- if (l_write_sigio_pid != -1)
- return;
-
- err = os_pipe(l_write_sigio_fds, 1, 1);
- if(err < 0){
- printk("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 1 failed, "
- "err = %d\n", -err);
- goto out_close1;
- }
-
- p = setup_initial_poll(l_sigio_private[1]);
- 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)
- goto out_unlock;
-
- write_sigio_pid = run_helper_thread(write_sigio_thread, NULL,
- CLONE_FILES | CLONE_VM, &stack, 0);
-
- if (write_sigio_pid < 0)
- goto out_clear;
-
- if (write_sigio_irq(l_write_sigio_fds[0]))
- goto out_kill;
-
- /* Success, finally. */
- memcpy(write_sigio_fds, l_write_sigio_fds, sizeof(l_write_sigio_fds));
- memcpy(sigio_private, l_sigio_private, sizeof(l_sigio_private));
-
- current_poll = ((struct pollfds) { .poll = p,
- .used = 1,
- .size = 1 });
-
- sigio_unlock();
- return;
-
- out_kill:
- l_write_sigio_pid = write_sigio_pid;
- write_sigio_pid = -1;
- sigio_unlock();
- /* Going to call waitpid, avoid holding the lock. */
- os_kill_process(l_write_sigio_pid, 1);
- goto out_free;
-
- out_clear:
- write_sigio_pid = -1;
- out_unlock:
- sigio_unlock();
- out_free:
- kfree(p);
- out_close2:
- os_close_file(l_sigio_private[0]);
- os_close_file(l_sigio_private[1]);
- out_close1:
- os_close_file(l_write_sigio_fds[0]);
- os_close_file(l_write_sigio_fds[1]);
- return;
-}
-
-int read_sigio_fd(int fd)
-{
- int n;
- char c;
-
- n = os_read_file(fd, &c, sizeof(c));
- if(n != sizeof(c)){
- if(n < 0) {
- printk("read_sigio_fd - read failed, err = %d\n", -n);
- return(n);
- }
- else {
- printk("read_sigio_fd - short read, bytes = %d\n", n);
- return(-EIO);
- }
- }
- return(n);
-}
-
-static void sigio_cleanup(void)
-{
- if (write_sigio_pid != -1) {
- os_kill_process(write_sigio_pid, 1);
- write_sigio_pid = -1;
- }
-}
-
-__uml_exitcall(sigio_cleanup);
generated by cgit v1.1 at 2025-08-17 11:09:15 +0000