[PATCH] uml: move SIGIO startup code to os-Linux/start_up.c
The serial UML OS-abstraction layer patch (um/kernel dir).
This moves all startup code from sigio_user.c file under os-Linux dir
Signed-off-by: Gennady Sharapov <Gennady.V.Sharapov@intel.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/arch/um/os-Linux/start_up.c b/arch/um/os-Linux/start_up.c
index 829d6b0..3275313 100644
--- a/arch/um/os-Linux/start_up.c
+++ b/arch/um/os-Linux/start_up.c
@@ -3,6 +3,7 @@
* Licensed under the GPL
*/
+#include <pty.h>
#include <stdio.h>
#include <stddef.h>
#include <stdarg.h>
@@ -539,3 +540,130 @@
return(1);
}
+
+/* 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;
+
+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 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);
+
+ close(master);
+ close(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...");
+
+ close(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);
+}
+
+void os_check_bugs(void)
+{
+ check_ptrace();
+ check_sigio();
+ check_devanon();
+}
+