[PATCH] uml ubd driver: do not store error codes as ->fd

To simplify error handling, make sure fd is saved into ubd_dev->fd only when
we are sure it is an fd and not an error code.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 10 insertions, 7 deletions

diff --git a/arch/um/drivers/ubd_kern.c b/arch/um/drivers/ubd_kern.c
index 3e3bb22c3ce8..125a63fd3a45 100644
--- a/arch/um/drivers/ubd_kern.c
+++ b/arch/um/drivers/ubd_kern.c
@@ -578,33 +578,36 @@ static int ubd_open_dev(struct ubd *ubd_dev)
         struct openflags flags;
         char **back_ptr;
         int err, create_cow, *create_ptr;
+        int fd;
 
         ubd_dev->openflags = ubd_dev->boot_openflags;
         create_cow = 0;
         create_ptr = (ubd_dev->cow.file != NULL) ? &create_cow : NULL;
         back_ptr = ubd_dev->no_cow ? NULL : &ubd_dev->cow.file;
-        ubd_dev->fd = open_ubd_file(ubd_dev->file, &ubd_dev->openflags, ubd_dev->shared,
+
+        fd = open_ubd_file(ubd_dev->file, &ubd_dev->openflags, ubd_dev->shared,
                                 back_ptr, &ubd_dev->cow.bitmap_offset,
                                 &ubd_dev->cow.bitmap_len, &ubd_dev->cow.data_offset,
                                 create_ptr);
 
-        if((ubd_dev->fd == -ENOENT) && create_cow){
-                ubd_dev->fd = create_cow_file(ubd_dev->file, ubd_dev->cow.file,
+        if((fd == -ENOENT) && create_cow){
+                fd = create_cow_file(ubd_dev->file, ubd_dev->cow.file,
                                           ubd_dev->openflags, 1 << 9, PAGE_SIZE,
                                           &ubd_dev->cow.bitmap_offset,
                                           &ubd_dev->cow.bitmap_len,
                                           &ubd_dev->cow.data_offset);
-                if(ubd_dev->fd >= 0){
+                if(fd >= 0){
                         printk(KERN_INFO "Creating \"%s\" as COW file for "
                                "\"%s\"\n", ubd_dev->file, ubd_dev->cow.file);
                 }
         }
 
-        if(ubd_dev->fd < 0){
+        if(fd < 0){
                 printk("Failed to open '%s', errno = %d\n", ubd_dev->file,
-                       -ubd_dev->fd);
-                return(ubd_dev->fd);
+                       -fd);
+                return fd;
         }
+        ubd_dev->fd = fd;
 
         if(ubd_dev->cow.file != NULL){
                 err = -ENOMEM;