fs/9p: Fix atomic_open
Return EEXISTS if requested file already exists, without this patch open
call will always succeed even if the file exists and user specified
O_CREAT|O_EXCL.
Following test code can be used to verify this patch. Without this patch
executing following test code on 9p mount will result in printing 'test case
failed' always.
main()
{
int fd;
/* first create the file */
fd = open("./file", O_CREAT|O_WRONLY);
if (fd < 0) {
perror("open");
return -1;
}
close(fd);
/* Now opening same file with O_CREAT|O_EXCL should fail */
fd = open("./file", O_CREAT|O_EXCL);
if (fd < 0 && errno == EEXIST)
printf("test case pass\n");
else
printf("test case failed\n");
close(fd);
return 0;
}
Signed-off-by: M. Mohan Kumar <mohan@in.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
diff --git a/fs/9p/vfs_inode_dotl.c b/fs/9p/vfs_inode_dotl.c
index edd41d9..8d24ad6 100644
--- a/fs/9p/vfs_inode_dotl.c
+++ b/fs/9p/vfs_inode_dotl.c
@@ -267,8 +267,14 @@
}
/* Only creates */
- if (!(flags & O_CREAT) || dentry->d_inode)
- return finish_no_open(file, res);
+ if (!(flags & O_CREAT))
+ return finish_no_open(file, res);
+ else if (dentry->d_inode) {
+ if ((flags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))
+ return -EEXIST;
+ else
+ return finish_no_open(file, res);
+ }
v9ses = v9fs_inode2v9ses(dir);