diff options
Diffstat (limited to 'arch/um/drivers/harddog_user.c')
-rw-r--r-- | arch/um/drivers/harddog_user.c | 127 |
1 files changed, 127 insertions, 0 deletions
diff --git a/arch/um/drivers/harddog_user.c b/arch/um/drivers/harddog_user.c new file mode 100644 index 000000000..3aa8b0d52 --- /dev/null +++ b/arch/um/drivers/harddog_user.c @@ -0,0 +1,127 @@ +/* + * Copyright (C) 2002 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com) + * Licensed under the GPL + */ + +#include <stdio.h> +#include <unistd.h> +#include <errno.h> +#include <os.h> + +struct dog_data { + int stdin_fd; + int stdout_fd; + int close_me[2]; +}; + +static void pre_exec(void *d) +{ + struct dog_data *data = d; + + dup2(data->stdin_fd, 0); + dup2(data->stdout_fd, 1); + dup2(data->stdout_fd, 2); + close(data->stdin_fd); + close(data->stdout_fd); + close(data->close_me[0]); + close(data->close_me[1]); +} + +int start_watchdog(int *in_fd_ret, int *out_fd_ret, char *sock) +{ + struct dog_data data; + int in_fds[2], out_fds[2], pid, n, err; + char pid_buf[sizeof("nnnnnnn\0")], c; + char *pid_args[] = { "/usr/bin/uml_watchdog", "-pid", pid_buf, NULL }; + char *mconsole_args[] = { "/usr/bin/uml_watchdog", "-mconsole", NULL, + NULL }; + char **args = NULL; + + err = os_pipe(in_fds, 1, 0); + if (err < 0) { + printk("harddog_open - os_pipe failed, err = %d\n", -err); + goto out; + } + + err = os_pipe(out_fds, 1, 0); + if (err < 0) { + printk("harddog_open - os_pipe failed, err = %d\n", -err); + goto out_close_in; + } + + data.stdin_fd = out_fds[0]; + data.stdout_fd = in_fds[1]; + data.close_me[0] = out_fds[1]; + data.close_me[1] = in_fds[0]; + + if (sock != NULL) { + mconsole_args[2] = sock; + args = mconsole_args; + } + else { + /* XXX The os_getpid() is not SMP correct */ + sprintf(pid_buf, "%d", os_getpid()); + args = pid_args; + } + + pid = run_helper(pre_exec, &data, args); + + close(out_fds[0]); + close(in_fds[1]); + + if (pid < 0) { + err = -pid; + printk("harddog_open - run_helper failed, errno = %d\n", -err); + goto out_close_out; + } + + n = read(in_fds[0], &c, sizeof(c)); + if (n == 0) { + printk("harddog_open - EOF on watchdog pipe\n"); + helper_wait(pid); + err = -EIO; + goto out_close_out; + } + else if (n < 0) { + printk("harddog_open - read of watchdog pipe failed, " + "err = %d\n", errno); + helper_wait(pid); + err = n; + goto out_close_out; + } + *in_fd_ret = in_fds[0]; + *out_fd_ret = out_fds[1]; + return 0; + + out_close_in: + close(in_fds[0]); + close(in_fds[1]); + out_close_out: + close(out_fds[0]); + close(out_fds[1]); + out: + return err; +} + +void stop_watchdog(int in_fd, int out_fd) +{ + close(in_fd); + close(out_fd); +} + +int ping_watchdog(int fd) +{ + int n; + char c = '\n'; + + n = write(fd, &c, sizeof(c)); + if (n != sizeof(c)) { + printk("ping_watchdog - write failed, ret = %d, err = %d\n", + n, errno); + if (n < 0) + return n; + return -EIO; + } + return 1; + +} |