uml: userspace files should call libc directly

[safe/jmp/linux-2.6] / arch / um / os-Linux / helper.c

diff --git a/arch/um/os-Linux/helper.c b/arch/um/os-Linux/helper.c
index a375cc1..7a72dbb 100644 (file)
--- a/arch/um/os-Linux/helper.c
+++ b/arch/um/os-Linux/helper.c
@@ -11,11 +11,12 @@
 #include <limits.h>
 #include <sys/signal.h>
 #include <sys/wait.h>
+#include <sys/socket.h>
 #include "user.h"
 #include "kern_util.h"
-#include "user_util.h"
 #include "os.h"
 #include "um_malloc.h"
+#include "kern_constants.h"
 
 struct helper_data {
        void (*pre_exec)(void*);
@@ -34,8 +35,9 @@ static int helper_child(void *arg)
        if (data->pre_exec != NULL)
                (*data->pre_exec)(data->pre_data);
        errval = execvp_noalloc(data->buf, argv[0], argv);
-       printk("helper_child - execvp of '%s' failed - errno = %d\n", argv[0], -errval);
-       os_write_file(data->fd, &errval, sizeof(errval));
+       printk("helper_child - execvp of '%s' failed - errno = %d\n", argv[0],
+              -errval);
+       write(data->fd, &errval, sizeof(errval));
        kill(os_getpid(), SIGKILL);
        return 0;
 }
@@ -43,40 +45,37 @@ static int helper_child(void *arg)
 /* Returns either the pid of the child process we run or -E* on failure.
  * XXX The alloc_stack here breaks if this is called in the tracing thread, so
  * we need to receive a preallocated stack (a local buffer is ok). */
-int run_helper(void (*pre_exec)(void *), void *pre_data, char **argv,
-              unsigned long *stack_out)
+int run_helper(void (*pre_exec)(void *), void *pre_data, char **argv)
 {
        struct helper_data data;
        unsigned long stack, sp;
        int pid, fds[2], ret, n;
 
-       if ((stack_out != NULL) && (*stack_out != 0))
-               stack = *stack_out;
-       else
-               stack = alloc_stack(0, __cant_sleep());
+       stack = alloc_stack(0, __cant_sleep());
        if (stack == 0)
                return -ENOMEM;
 
-       ret = os_pipe(fds, 1, 0);
+       ret = socketpair(AF_UNIX, SOCK_STREAM, 0, fds);
        if (ret < 0) {
-               printk("run_helper : pipe failed, ret = %d\n", -ret);
+               ret = -errno;
+               printk("run_helper : pipe failed, errno = %d\n", errno);
                goto out_free;
        }
 
-       ret = os_set_exec_close(fds[1], 1);
+       ret = os_set_exec_close(fds[1]);
        if (ret < 0) {
                printk("run_helper : setting FD_CLOEXEC failed, ret = %d\n",
                       -ret);
                goto out_close;
        }
 
-       sp = stack + page_size() - sizeof(void *);
+       sp = stack + UM_KERN_PAGE_SIZE - sizeof(void *);
        data.pre_exec = pre_exec;
        data.pre_data = pre_data;
        data.argv = argv;
        data.fd = fds[1];
-       data.buf = __cant_sleep() ? um_kmalloc_atomic(PATH_MAX) :
-                                       um_kmalloc(PATH_MAX);
+       data.buf = __cant_sleep() ? kmalloc(PATH_MAX, UM_GFP_ATOMIC) :
+                                       kmalloc(PATH_MAX, UM_GFP_KERNEL);
        pid = clone(helper_child, (void *) sp, CLONE_VM | SIGCHLD, &data);
        if (pid < 0) {
                ret = -errno;
@@ -87,13 +86,16 @@ int run_helper(void (*pre_exec)(void *), void *pre_data, char **argv,
        close(fds[1]);
        fds[1] = -1;
 
-       /* Read the errno value from the child, if the exec failed, or get 0 if
-        * the exec succeeded because the pipe fd was set as close-on-exec. */
-       n = os_read_file(fds[0], &ret, sizeof(ret));
+       /*
+        * Read the errno value from the child, if the exec failed, or get 0 if
+        * the exec succeeded because the pipe fd was set as close-on-exec.
+        */
+       n = read(fds[0], &ret, sizeof(ret));
        if (n == 0) {
                ret = pid;
        } else {
                if (n < 0) {
+                       n = -errno;
                        printk("run_helper : read on pipe failed, ret = %d\n",
                               -n);
                        ret = n;
@@ -109,22 +111,21 @@ out_close:
                close(fds[1]);
        close(fds[0]);
 out_free:
-       if ((stack_out == NULL) || (*stack_out == 0))
-               free_stack(stack, 0);
+       free_stack(stack, 0);
        return ret;
 }
 
 int run_helper_thread(int (*proc)(void *), void *arg, unsigned int flags,
-                     unsigned long *stack_out, int stack_order)
+                     unsigned long *stack_out)
 {
        unsigned long stack, sp;
        int pid, status, err;
 
-       stack = alloc_stack(stack_order, __cant_sleep());
+       stack = alloc_stack(0, __cant_sleep());
        if (stack == 0)
                return -ENOMEM;
 
-       sp = stack + (page_size() << stack_order) - sizeof(void *);
+       sp = stack + UM_KERN_PAGE_SIZE - sizeof(void *);
        pid = clone(proc, (void *) sp, flags | SIGCHLD, arg);
        if (pid < 0) {
                err = -errno;
@@ -143,7 +144,7 @@ int run_helper_thread(int (*proc)(void *), void *arg, unsigned int flags,
                if (!WIFEXITED(status) || (WEXITSTATUS(status) != 0))
                        printk("run_helper_thread - thread returned status "
                               "0x%x\n", status);
-               free_stack(stack, stack_order);
+               free_stack(stack, 0);
        } else
                *stack_out = stack;
        return pid;