Pull mca-cleanup into release branch

[powerpc.git] / arch / um / drivers / ubd_kern.c

diff --git a/arch/um/drivers/ubd_kern.c b/arch/um/drivers/ubd_kern.c
index 3a93c6f..fa617e0 100644 (file)
--- a/arch/um/drivers/ubd_kern.c
+++ b/arch/um/drivers/ubd_kern.c
@@ -1073,7 +1073,6 @@ static int ubd_getgeo(struct block_device *bdev, struct hd_geometry *geo)
 static int ubd_ioctl(struct inode * inode, struct file * file,
                     unsigned int cmd, unsigned long arg)
 {
-       struct hd_geometry __user *loc = (struct hd_geometry __user *) arg;
        struct ubd *dev = inode->i_bdev->bd_disk->private_data;
        struct hd_driveid ubd_id = {
                .cyls           = 0,
@@ -1104,37 +1103,39 @@ static int ubd_ioctl(struct inode * inode, struct file * file,
        return(-EINVAL);
 }
 
-static int same_backing_files(char *from_cmdline, char *from_cow, char *cow)
+static int path_requires_switch(char *from_cmdline, char *from_cow, char *cow)
 {
        struct uml_stat buf1, buf2;
        int err;
 
-       if(from_cmdline == NULL) return(1);
-       if(!strcmp(from_cmdline, from_cow)) return(1);
+       if(from_cmdline == NULL)
+               return 0;
+       if(!strcmp(from_cmdline, from_cow))
+               return 0;
 
        err = os_stat_file(from_cmdline, &buf1);
        if(err < 0){
                printk("Couldn't stat '%s', err = %d\n", from_cmdline, -err);
-               return(1);
+               return 0;
        }
        err = os_stat_file(from_cow, &buf2);
        if(err < 0){
                printk("Couldn't stat '%s', err = %d\n", from_cow, -err);
-               return(1);
+               return 1;
        }
        if((buf1.ust_dev == buf2.ust_dev) && (buf1.ust_ino == buf2.ust_ino))
-               return(1);
+               return 0;
 
        printk("Backing file mismatch - \"%s\" requested,\n"
               "\"%s\" specified in COW header of \"%s\"\n",
               from_cmdline, from_cow, cow);
-       return(0);
+       return 1;
 }
 
 static int backing_file_mismatch(char *file, __u64 size, time_t mtime)
 {
        unsigned long modtime;
-       long long actual;
+       unsigned long long actual;
        int err;
 
        err = os_file_modtime(file, &modtime);
@@ -1190,18 +1191,19 @@ int open_ubd_file(char *file, struct openflags *openflags,
        unsigned long long size;
        __u32 version, align;
        char *backing_file;
-       int fd, err, sectorsize, same, mode = 0644;
+       int fd, err, sectorsize, asked_switch, mode = 0644;
 
        fd = os_open_file(file, *openflags, mode);
-       if(fd < 0){
-               if((fd == -ENOENT) && (create_cow_out != NULL))
+       if (fd < 0) {
+               if ((fd == -ENOENT) && (create_cow_out != NULL))
                        *create_cow_out = 1;
-                if(!openflags->w ||
-                   ((fd != -EROFS) && (fd != -EACCES))) return(fd);
+                if (!openflags->w ||
+                   ((fd != -EROFS) && (fd != -EACCES)))
+                       return fd;
                openflags->w = 0;
                fd = os_open_file(file, *openflags, mode);
-               if(fd < 0)
-                       return(fd);
+               if (fd < 0)
+                       return fd;
         }
 
        err = os_lock_file(fd, openflags->w);
@@ -1210,7 +1212,9 @@ int open_ubd_file(char *file, struct openflags *openflags,
                goto out_close;
        }
 
-       if(backing_file_out == NULL) return(fd);
+       /* Succesful return case! */
+       if(backing_file_out == NULL)
+               return(fd);
 
        err = read_cow_header(file_reader, &fd, &version, &backing_file, &mtime,
                              &size, &sectorsize, &align, bitmap_offset_out);
@@ -1219,34 +1223,34 @@ int open_ubd_file(char *file, struct openflags *openflags,
                       "errno = %d\n", file, -err);
                goto out_close;
        }
-       if(err) return(fd);
-
-       if(backing_file_out == NULL) return(fd);
+       if(err)
+               return(fd);
 
-       same = same_backing_files(*backing_file_out, backing_file, file);
+       asked_switch = path_requires_switch(*backing_file_out, backing_file, file);
 
-       if(!same && !backing_file_mismatch(*backing_file_out, size, mtime)){
+       /* Allow switching only if no mismatch. */
+       if (asked_switch && !backing_file_mismatch(*backing_file_out, size, mtime)) {
                printk("Switching backing file to '%s'\n", *backing_file_out);
                err = write_cow_header(file, fd, *backing_file_out,
                                       sectorsize, align, &size);
-               if(err){
+               if (err) {
                        printk("Switch failed, errno = %d\n", -err);
-                       return(err);
+                       goto out_close;
                }
-       }
-       else {
+       } else {
                *backing_file_out = backing_file;
                err = backing_file_mismatch(*backing_file_out, size, mtime);
-               if(err) goto out_close;
+               if (err)
+                       goto out_close;
        }
 
        cow_sizes(version, size, sectorsize, align, *bitmap_offset_out,
                  bitmap_len_out, data_offset_out);
 
-        return(fd);
+        return fd;
  out_close:
        os_close_file(fd);
-       return(err);
+       return err;
 }
 
 int create_cow_file(char *cow_file, char *backing_file, struct openflags flags,