uml: simplify helper stack handling

run_helper and run_helper_thread had arguments which were the same in all
callers.  run_helper's stack_out was always NULL and run_helper_thread's
stack_order was always 0.  These are now gone, and the constants folded
into the code.

Also fixed leaks of the helper stack in the AIO and SIGIO code.

Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 6 insertions, 5 deletions

diff --git a/arch/um/os-Linux/aio.c b/arch/um/os-Linux/aio.c
index 9bf944f6a1db..b126df4ea168 100644
--- a/arch/um/os-Linux/aio.c
+++ b/arch/um/os-Linux/aio.c
@@ -177,6 +177,7 @@ static int do_not_aio(struct aio_thread_req *req)
 static int aio_req_fd_r = -1;
 static int aio_req_fd_w = -1;
 static int aio_pid = -1;
+static unsigned long aio_stack;
 
 static int not_aio_thread(void *arg)
 {
@@ -212,7 +213,6 @@ static int not_aio_thread(void *arg)
 
 static int init_aio_24(void)
 {
-        unsigned long stack;
         int fds[2], err;
 
         err = os_pipe(fds, 1, 1);
@@ -227,7 +227,7 @@ static int init_aio_24(void)
                 goto out_close_pipe;
 
         err = run_helper_thread(not_aio_thread, NULL,
-                                CLONE_FILES | CLONE_VM | SIGCHLD, &stack, 0);
+                                CLONE_FILES | CLONE_VM | SIGCHLD, &aio_stack);
         if(err < 0)
                 goto out_close_pipe;
 
@@ -252,7 +252,6 @@ out:
 #define DEFAULT_24_AIO 0
 static int init_aio_26(void)
 {
-        unsigned long stack;
         int err;
 
         if(io_setup(256, &ctx)){
@@ -263,7 +262,7 @@ static int init_aio_26(void)
         }
 
         err = run_helper_thread(aio_thread, NULL,
-                                CLONE_FILES | CLONE_VM | SIGCHLD, &stack, 0);
+                                CLONE_FILES | CLONE_VM | SIGCHLD, &aio_stack);
         if(err < 0)
                 return err;
 
@@ -365,8 +364,10 @@ __initcall(init_aio);
 
 static void exit_aio(void)
 {
-        if(aio_pid != -1)
+        if (aio_pid != -1) {
                 os_kill_process(aio_pid, 1);
+                free_stack(aio_stack, 0);
+        }
 }
 
 __uml_exitcall(exit_aio);