fdget(), trivial conversions

fdget() is the first thing done in scope, all matching fdput() are
immediately followed by leaving the scope.

Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

12 files changed, 74 insertions, 137 deletions

diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 226c91fe31a7..adb591b1d071 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -1308,9 +1308,9 @@ static noinline int __btrfs_ioctl_snap_create(struct file *file,
 		ret = btrfs_mksubvol(&file->f_path, idmap, name,
 				     namelen, NULL, readonly, inherit);
 	} else {
-		struct fd src = fdget(fd);
+		CLASS(fd, src)(fd);
 		struct inode *src_inode;
-		if (!fd_file(src)) {
+		if (fd_empty(src)) {
 			ret = -EINVAL;
 			goto out_drop_write;
 		}
@@ -1341,7 +1341,6 @@ static noinline int __btrfs_ioctl_snap_create(struct file *file,
 					       BTRFS_I(src_inode)->root,
 					       readonly, inherit);
 		}
-		fdput(src);
 	}
 out_drop_write:
 	mnt_drop_write_file(file);
diff --git a/fs/eventfd.c b/fs/eventfd.c
index 22c934f3a080..76129bfcd663 100644
--- a/fs/eventfd.c
+++ b/fs/eventfd.c
@@ -347,13 +347,10 @@ EXPORT_SYMBOL_GPL(eventfd_fget);
  */
 struct eventfd_ctx *eventfd_ctx_fdget(int fd)
 {
-	struct eventfd_ctx *ctx;
-	struct fd f = fdget(fd);
-	if (!fd_file(f))
+	CLASS(fd, f)(fd);
+	if (fd_empty(f))
 		return ERR_PTR(-EBADF);
-	ctx = eventfd_ctx_fileget(fd_file(f));
-	fdput(f);
-	return ctx;
+	return eventfd_ctx_fileget(fd_file(f));
 }
 EXPORT_SYMBOL_GPL(eventfd_ctx_fdget);
 
diff --git a/fs/eventpoll.c b/fs/eventpoll.c
index 1ae4542f0bd8..4607dcbc2851 100644
--- a/fs/eventpoll.c
+++ b/fs/eventpoll.c
@@ -2254,25 +2254,22 @@ int do_epoll_ctl(int epfd, int op, int fd, struct epoll_event *epds,
 {
 	int error;
 	int full_check = 0;
-	struct fd f, tf;
 	struct eventpoll *ep;
 	struct epitem *epi;
 	struct eventpoll *tep = NULL;
 
-	error = -EBADF;
-	f = fdget(epfd);
-	if (!fd_file(f))
-		goto error_return;
+	CLASS(fd, f)(epfd);
+	if (fd_empty(f))
+		return -EBADF;
 
 	/* Get the "struct file *" for the target file */
-	tf = fdget(fd);
-	if (!fd_file(tf))
-		goto error_fput;
+	CLASS(fd, tf)(fd);
+	if (fd_empty(tf))
+		return -EBADF;
 
 	/* The target file descriptor must support poll */
-	error = -EPERM;
 	if (!file_can_poll(fd_file(tf)))
-		goto error_tgt_fput;
+		return -EPERM;
 
 	/* Check if EPOLLWAKEUP is allowed */
 	if (ep_op_has_event(op))
@@ -2391,12 +2388,6 @@ error_tgt_fput:
 		loop_check_gen++;
 		mutex_unlock(&epnested_mutex);
 	}
-
-	fdput(tf);
-error_fput:
-	fdput(f);
-error_return:
-
 	return error;
 }
 
diff --git a/fs/fhandle.c b/fs/fhandle.c
index 82df28d45cd7..5f801139358e 100644
--- a/fs/fhandle.c
+++ b/fs/fhandle.c
@@ -139,12 +139,11 @@ static int get_path_from_fd(int fd, struct path *root)
 		path_get(root);
 		spin_unlock(&fs->lock);
 	} else {
-		struct fd f = fdget(fd);
-		if (!fd_file(f))
+		CLASS(fd, f)(fd);
+		if (fd_empty(f))
 			return -EBADF;
 		*root = fd_file(f)->f_path;
 		path_get(root);
-		fdput(f);
 	}
 
 	return 0;
diff --git a/fs/ioctl.c b/fs/ioctl.c
index 6e0c954388d4..638a36be31c1 100644
--- a/fs/ioctl.c
+++ b/fs/ioctl.c
@@ -231,11 +231,11 @@ static int ioctl_fiemap(struct file *filp, struct fiemap __user *ufiemap)
 static long ioctl_file_clone(struct file *dst_file, unsigned long srcfd,
 			     u64 off, u64 olen, u64 destoff)
 {
-	struct fd src_file = fdget(srcfd);
+	CLASS(fd, src_file)(srcfd);
 	loff_t cloned;
 	int ret;
 
-	if (!fd_file(src_file))
+	if (fd_empty(src_file))
 		return -EBADF;
 	cloned = vfs_clone_file_range(fd_file(src_file), off, dst_file, destoff,
 				      olen, 0);
@@ -245,7 +245,6 @@ static long ioctl_file_clone(struct file *dst_file, unsigned long srcfd,
 		ret = -EINVAL;
 	else
 		ret = 0;
-	fdput(src_file);
 	return ret;
 }
 
@@ -892,22 +891,20 @@ static int do_vfs_ioctl(struct file *filp, unsigned int fd,
 
 SYSCALL_DEFINE3(ioctl, unsigned int, fd, unsigned int, cmd, unsigned long, arg)
 {
-	struct fd f = fdget(fd);
+	CLASS(fd, f)(fd);
 	int error;
 
-	if (!fd_file(f))
+	if (fd_empty(f))
 		return -EBADF;
 
 	error = security_file_ioctl(fd_file(f), cmd, arg);
 	if (error)
-		goto out;
+		return error;
 
 	error = do_vfs_ioctl(fd_file(f), fd, cmd, arg);
 	if (error == -ENOIOCTLCMD)
 		error = vfs_ioctl(fd_file(f), cmd, arg);
 
-out:
-	fdput(f);
 	return error;
 }
 
@@ -950,15 +947,15 @@ EXPORT_SYMBOL(compat_ptr_ioctl);
 COMPAT_SYSCALL_DEFINE3(ioctl, unsigned int, fd, unsigned int, cmd,
 		       compat_ulong_t, arg)
 {
-	struct fd f = fdget(fd);
+	CLASS(fd, f)(fd);
 	int error;
 
-	if (!fd_file(f))
+	if (fd_empty(f))
 		return -EBADF;
 
 	error = security_file_ioctl_compat(fd_file(f), cmd, arg);
 	if (error)
-		goto out;
+		return error;
 
 	switch (cmd) {
 	/* FICLONE takes an int argument, so don't use compat_ptr() */
@@ -1009,10 +1006,6 @@ COMPAT_SYSCALL_DEFINE3(ioctl, unsigned int, fd, unsigned int, cmd,
 			error = -ENOTTY;
 		break;
 	}
-
- out:
-	fdput(f);
-
 	return error;
 }
 #endif
diff --git a/fs/kernel_read_file.c b/fs/kernel_read_file.c
index 9ff37ae650ea..de32c95d823d 100644
--- a/fs/kernel_read_file.c
+++ b/fs/kernel_read_file.c
@@ -175,15 +175,11 @@ ssize_t kernel_read_file_from_fd(int fd, loff_t offset, void **buf,
 				 size_t buf_size, size_t *file_size,
 				 enum kernel_read_file_id id)
 {
-	struct fd f = fdget(fd);
-	ssize_t ret = -EBADF;
+	CLASS(fd, f)(fd);
 
-	if (!fd_file(f) || !(fd_file(f)->f_mode & FMODE_READ))
-		goto out;
+	if (fd_empty(f) || !(fd_file(f)->f_mode & FMODE_READ))
+		return -EBADF;
 
-	ret = kernel_read_file(fd_file(f), offset, buf, buf_size, file_size, id);
-out:
-	fdput(f);
-	return ret;
+	return kernel_read_file(fd_file(f), offset, buf, buf_size, file_size, id);
 }
 EXPORT_SYMBOL_GPL(kernel_read_file_from_fd);
diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c
index 9644bc72e457..07c5ffc8523b 100644
--- a/fs/notify/fanotify/fanotify_user.c
+++ b/fs/notify/fanotify/fanotify_user.c
@@ -1003,22 +1003,17 @@ static int fanotify_find_path(int dfd, const char __user *filename,
 		 dfd, filename, flags);
 
 	if (filename == NULL) {
-		struct fd f = fdget(dfd);
+		CLASS(fd, f)(dfd);
 
-		ret = -EBADF;
-		if (!fd_file(f))
-			goto out;
+		if (fd_empty(f))
+			return -EBADF;
 
-		ret = -ENOTDIR;
 		if ((flags & FAN_MARK_ONLYDIR) &&
-		    !(S_ISDIR(file_inode(fd_file(f))->i_mode))) {
-			fdput(f);
-			goto out;
-		}
+		    !(S_ISDIR(file_inode(fd_file(f))->i_mode)))
+			return -ENOTDIR;
 
 		*path = fd_file(f)->f_path;
 		path_get(path);
-		fdput(f);
 	} else {
 		unsigned int lookup_flags = 0;
 
diff --git a/fs/notify/inotify/inotify_user.c b/fs/notify/inotify/inotify_user.c
index 0794dcaf1e47..dc645af2a6ad 100644
--- a/fs/notify/inotify/inotify_user.c
+++ b/fs/notify/inotify/inotify_user.c
@@ -794,33 +794,26 @@ SYSCALL_DEFINE2(inotify_rm_watch, int, fd, __s32, wd)
 {
 	struct fsnotify_group *group;
 	struct inotify_inode_mark *i_mark;
-	struct fd f;
-	int ret = -EINVAL;
+	CLASS(fd, f)(fd);
 
-	f = fdget(fd);
-	if (unlikely(!fd_file(f)))
+	if (fd_empty(f))
 		return -EBADF;
 
 	/* verify that this is indeed an inotify instance */
 	if (unlikely(fd_file(f)->f_op != &inotify_fops))
-		goto out;
+		return -EINVAL;
 
 	group = fd_file(f)->private_data;
 
 	i_mark = inotify_idr_find(group, wd);
 	if (unlikely(!i_mark))
-		goto out;
-
-	ret = 0;
+		return -EINVAL;
 
 	fsnotify_destroy_mark(&i_mark->fsn_mark, group);
 
 	/* match ref taken by inotify_idr_find */
 	fsnotify_put_mark(&i_mark->fsn_mark);
-
-out:
-	fdput(f);
-	return ret;
+	return 0;
 }
 
 /*
diff --git a/fs/open.c b/fs/open.c
index a0c1fa3f60d5..24d22f4222f0 100644
--- a/fs/open.c
+++ b/fs/open.c
@@ -349,14 +349,12 @@ EXPORT_SYMBOL_GPL(vfs_fallocate);
 
 int ksys_fallocate(int fd, int mode, loff_t offset, loff_t len)
 {
-	struct fd f = fdget(fd);
-	int error = -EBADF;
+	CLASS(fd, f)(fd);
 
-	if (fd_file(f)) {
-		error = vfs_fallocate(fd_file(f), mode, offset, len);
-		fdput(f);
-	}
-	return error;
+	if (fd_empty(f))
+		return -EBADF;
+
+	return vfs_fallocate(fd_file(f), mode, offset, len);
 }
 
 SYSCALL_DEFINE4(fallocate, int, fd, int, mode, loff_t, offset, loff_t, len)
@@ -666,14 +664,12 @@ int vfs_fchmod(struct file *file, umode_t mode)
 
 SYSCALL_DEFINE2(fchmod, unsigned int, fd, umode_t, mode)
 {
-	struct fd f = fdget(fd);
-	int err = -EBADF;
+	CLASS(fd, f)(fd);
 
-	if (fd_file(f)) {
-		err = vfs_fchmod(fd_file(f), mode);
-		fdput(f);
-	}
-	return err;
+	if (fd_empty(f))
+		return -EBADF;
+
+	return vfs_fchmod(fd_file(f), mode);
 }
 
 static int do_fchmodat(int dfd, const char __user *filename, umode_t mode,
@@ -860,14 +856,12 @@ int vfs_fchown(struct file *file, uid_t user, gid_t group)
 
 int ksys_fchown(unsigned int fd, uid_t user, gid_t group)
 {
-	struct fd f = fdget(fd);
-	int error = -EBADF;
+	CLASS(fd, f)(fd);
 
-	if (fd_file(f)) {
-		error = vfs_fchown(fd_file(f), user, group);
-		fdput(f);
-	}
-	return error;
+	if (fd_empty(f))
+		return -EBADF;
+
+	return vfs_fchown(fd_file(f), user, group);
 }
 
 SYSCALL_DEFINE3(fchown, unsigned int, fd, uid_t, user, gid_t, group)
diff --git a/fs/read_write.c b/fs/read_write.c
index ef3ee3725714..5e3df2d39283 100644
--- a/fs/read_write.c
+++ b/fs/read_write.c
@@ -1663,36 +1663,32 @@ SYSCALL_DEFINE6(copy_file_range, int, fd_in, loff_t __user *, off_in,
 {
 	loff_t pos_in;
 	loff_t pos_out;
-	struct fd f_in;
-	struct fd f_out;
 	ssize_t ret = -EBADF;
 
-	f_in = fdget(fd_in);
-	if (!fd_file(f_in))
-		goto out2;
+	CLASS(fd, f_in)(fd_in);
+	if (fd_empty(f_in))
+		return -EBADF;
 
-	f_out = fdget(fd_out);
-	if (!fd_file(f_out))
-		goto out1;
+	CLASS(fd, f_out)(fd_out);
+	if (fd_empty(f_out))
+		return -EBADF;
 
-	ret = -EFAULT;
 	if (off_in) {
 		if (copy_from_user(&pos_in, off_in, sizeof(loff_t)))
-			goto out;
+			return -EFAULT;
 	} else {
 		pos_in = fd_file(f_in)->f_pos;
 	}
 
 	if (off_out) {
 		if (copy_from_user(&pos_out, off_out, sizeof(loff_t)))
-			goto out;
+			return -EFAULT;
 	} else {
 		pos_out = fd_file(f_out)->f_pos;
 	}
 
-	ret = -EINVAL;
 	if (flags != 0)
-		goto out;
+		return -EINVAL;
 
 	ret = vfs_copy_file_range(fd_file(f_in), pos_in, fd_file(f_out), pos_out, len,
 				  flags);
@@ -1714,12 +1710,6 @@ SYSCALL_DEFINE6(copy_file_range, int, fd_in, loff_t __user *, off_in,
 			fd_file(f_out)->f_pos = pos_out;
 		}
 	}
-
-out:
-	fdput(f_out);
-out1:
-	fdput(f_in);
-out2:
 	return ret;
 }
 
diff --git a/fs/signalfd.c b/fs/signalfd.c
index 736bebf93591..d1a5f43ce466 100644
--- a/fs/signalfd.c
+++ b/fs/signalfd.c
@@ -288,20 +288,17 @@ static int do_signalfd4(int ufd, sigset_t *mask, int flags)
 
 		fd_install(ufd, file);
 	} else {
-		struct fd f = fdget(ufd);
-		if (!fd_file(f))
+		CLASS(fd, f)(ufd);
+		if (fd_empty(f))
 			return -EBADF;
 		ctx = fd_file(f)->private_data;
-		if (fd_file(f)->f_op != &signalfd_fops) {
-			fdput(f);
+		if (fd_file(f)->f_op != &signalfd_fops)
 			return -EINVAL;
-		}
 		spin_lock_irq(&current->sighand->siglock);
 		ctx->sigmask = *mask;
 		spin_unlock_irq(&current->sighand->siglock);
 
 		wake_up(&current->sighand->signalfd_wqh);
-		fdput(f);
 	}
 
 	return ufd;
diff --git a/fs/sync.c b/fs/sync.c
index 67df255eb189..2955cd4c77a3 100644
--- a/fs/sync.c
+++ b/fs/sync.c
@@ -148,11 +148,11 @@ void emergency_sync(void)
  */
 SYSCALL_DEFINE1(syncfs, int, fd)
 {
-	struct fd f = fdget(fd);
+	CLASS(fd, f)(fd);
 	struct super_block *sb;
 	int ret, ret2;
 
-	if (!fd_file(f))
+	if (fd_empty(f))
 		return -EBADF;
 	sb = fd_file(f)->f_path.dentry->d_sb;
 
@@ -162,7 +162,6 @@ SYSCALL_DEFINE1(syncfs, int, fd)
 
 	ret2 = errseq_check_and_advance(&sb->s_wb_err, &fd_file(f)->f_sb_err);
 
-	fdput(f);
 	return ret ? ret : ret2;
 }
 
@@ -205,14 +204,12 @@ EXPORT_SYMBOL(vfs_fsync);
 
 static int do_fsync(unsigned int fd, int datasync)
 {
-	struct fd f = fdget(fd);
-	int ret = -EBADF;
+	CLASS(fd, f)(fd);
 
-	if (fd_file(f)) {
-		ret = vfs_fsync(fd_file(f), datasync);
-		fdput(f);
-	}
-	return ret;
+	if (fd_empty(f))
+		return -EBADF;
+
+	return vfs_fsync(fd_file(f), datasync);
 }
 
 SYSCALL_DEFINE1(fsync, unsigned int, fd)
@@ -355,16 +352,12 @@ out:
 int ksys_sync_file_range(int fd, loff_t offset, loff_t nbytes,
 			 unsigned int flags)
 {
-	int ret;
-	struct fd f;
+	CLASS(fd, f)(fd);
 
-	ret = -EBADF;
-	f = fdget(fd);
-	if (fd_file(f))
-		ret = sync_file_range(fd_file(f), offset, nbytes, flags);
+	if (fd_empty(f))
+		return -EBADF;
 
-	fdput(f);
-	return ret;
+	return sync_file_range(fd_file(f), offset, nbytes, flags);
 }
 
 SYSCALL_DEFINE4(sync_file_range, int, fd, loff_t, offset, loff_t, nbytes,