fs: fold open_check_o_direct into do_dentry_open

do_dentry_open is where we do the actual open of the file, so this is
where we should do our O_DIRECT sanity check to cover all potential
callers.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

fs/internal.h

@@ -111,7 +111,6 @@ extern struct file *do_filp_open(int dfd, struct filename *pathname,
 extern struct file *do_file_open_root(struct dentry *, struct vfsmount *,
 		const char *, const struct open_flags *);
 
-extern int open_check_o_direct(struct file *f);
 extern int vfs_open(const struct path *, struct file *, const struct cred *);
 extern struct file *filp_clone_open(struct file *);
 

fs/namei.c

@@ -3382,9 +3382,7 @@ static int do_last(struct nameidata *nd,
 		goto out;
 	*opened |= FILE_OPENED;
 opened:
-	error = open_check_o_direct(file);
-	if (!error)
-		error = ima_file_check(file, op->acc_mode, *opened);
+	error = ima_file_check(file, op->acc_mode, *opened);
 	if (!error && will_truncate)
 		error = handle_truncate(file);
 out:
@@ -3464,9 +3462,6 @@ static int do_tmpfile(struct nameidata *nd, unsigned flags,
 	error = finish_open(file, child, NULL, opened);
 	if (error)
 		goto out2;
-	error = open_check_o_direct(file);
-	if (error)
-		fput(file);
 out2:
 	mnt_drop_write(path.mnt);
 out:

fs/open.c

@@ -682,16 +682,6 @@ SYSCALL_DEFINE3(fchown, unsigned int, fd, uid_t, user, gid_t, group)
 	return error;
 }
 
-int open_check_o_direct(struct file *f)
-{
-	/* NB: we're sure to have correct a_ops only after f_op->open */
-	if (f->f_flags & O_DIRECT) {
-		if (!f->f_mapping->a_ops || !f->f_mapping->a_ops->direct_IO)
-			return -EINVAL;
-	}
-	return 0;
-}
-
 static int do_dentry_open(struct file *f,
 			  struct inode *inode,
 			  int (*open)(struct inode *, struct file *),
@@ -713,7 +703,7 @@ static int do_dentry_open(struct file *f,
 	if (unlikely(f->f_flags & O_PATH)) {
 		f->f_mode = FMODE_PATH;
 		f->f_op = &empty_fops;
-		return 0;
+		goto done;
 	}
 
 	if (f->f_mode & FMODE_WRITE && !special_file(inode->i_mode)) {
@@ -766,7 +756,12 @@ static int do_dentry_open(struct file *f,
 	f->f_flags &= ~(O_CREAT | O_EXCL | O_NOCTTY | O_TRUNC);
 
 	file_ra_state_init(&f->f_ra, f->f_mapping->host->i_mapping);
-
+done:
+	/* NB: we're sure to have correct a_ops only after f_op->open */
+	error = -EINVAL;
+	if ((f->f_flags & O_DIRECT) &&
+	    (!f->f_mapping->a_ops || !f->f_mapping->a_ops->direct_IO))
+	    	goto out_fput;
 	return 0;
 
 cleanup_all:
@@ -781,6 +776,9 @@ static int do_dentry_open(struct file *f,
 	f->f_path.dentry = NULL;
 	f->f_inode = NULL;
 	return error;
+out_fput:
+    	fput(f);
+	return error;
 }
 
 /**
@@ -878,20 +876,14 @@ struct file *dentry_open(const struct path *path, int flags,
 	BUG_ON(!path->mnt);
 
 	f = get_empty_filp();
-	if (!IS_ERR(f)) {
-		f->f_flags = flags;
-		error = vfs_open(path, f, cred);
-		if (!error) {
-			/* from now on we need fput() to dispose of f */
-			error = open_check_o_direct(f);
-			if (error) {
-				fput(f);
-				f = ERR_PTR(error);
-			}
-		} else { 
-			put_filp(f);
-			f = ERR_PTR(error);
-		}
+	if (IS_ERR(f))
+		return f;
+
+	f->f_flags = flags;
+	error = vfs_open(path, f, cred);
+	if (error) {
+		put_filp(f);
+		return ERR_PTR(error);
 	}
 	return f;
 }