new helper: file_inode(file)

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index 77061bf..4118e0b 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -1211,7 +1211,7 @@
 	struct extent_state *cached_state = NULL;
 	int i;
 	unsigned long index = pos >> PAGE_CACHE_SHIFT;
-	struct inode *inode = fdentry(file)->d_inode;
+	struct inode *inode = file_inode(file);
 	gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping);
 	int err = 0;
 	int faili = 0;
@@ -1298,7 +1298,7 @@
 					       struct iov_iter *i,
 					       loff_t pos)
 {
-	struct inode *inode = fdentry(file)->d_inode;
+	struct inode *inode = file_inode(file);
 	struct btrfs_root *root = BTRFS_I(inode)->root;
 	struct page **pages = NULL;
 	unsigned long first_index;
@@ -1486,7 +1486,7 @@
 				    unsigned long nr_segs, loff_t pos)
 {
 	struct file *file = iocb->ki_filp;
-	struct inode *inode = fdentry(file)->d_inode;
+	struct inode *inode = file_inode(file);
 	struct btrfs_root *root = BTRFS_I(inode)->root;
 	loff_t *ppos = &iocb->ki_pos;
 	u64 start_pos;
@@ -2087,7 +2087,7 @@
 static long btrfs_fallocate(struct file *file, int mode,
 			    loff_t offset, loff_t len)
 {
-	struct inode *inode = file->f_path.dentry->d_inode;
+	struct inode *inode = file_inode(file);
 	struct extent_state *cached_state = NULL;
 	u64 cur_offset;
 	u64 last_byte;
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 16d9e8e..02d946a 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -4342,7 +4342,7 @@
 static int btrfs_real_readdir(struct file *filp, void *dirent,
 			      filldir_t filldir)
 {
-	struct inode *inode = filp->f_dentry->d_inode;
+	struct inode *inode = file_inode(filp);
 	struct btrfs_root *root = BTRFS_I(inode)->root;
 	struct btrfs_item *item;
 	struct btrfs_dir_item *di;
@@ -6737,7 +6737,7 @@
 int btrfs_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
 {
 	struct page *page = vmf->page;
-	struct inode *inode = fdentry(vma->vm_file)->d_inode;
+	struct inode *inode = file_inode(vma->vm_file);
 	struct btrfs_root *root = BTRFS_I(inode)->root;
 	struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
 	struct btrfs_ordered_extent *ordered;
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 4b45167..61045ad 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -152,7 +152,7 @@
 
 static int btrfs_ioctl_getflags(struct file *file, void __user *arg)
 {
-	struct btrfs_inode *ip = BTRFS_I(file->f_path.dentry->d_inode);
+	struct btrfs_inode *ip = BTRFS_I(file_inode(file));
 	unsigned int flags = btrfs_flags_to_ioctl(ip->flags);
 
 	if (copy_to_user(arg, &flags, sizeof(flags)))
@@ -177,7 +177,7 @@
 
 static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
 {
-	struct inode *inode = file->f_path.dentry->d_inode;
+	struct inode *inode = file_inode(file);
 	struct btrfs_inode *ip = BTRFS_I(inode);
 	struct btrfs_root *root = ip->root;
 	struct btrfs_trans_handle *trans;
@@ -310,7 +310,7 @@
 
 static int btrfs_ioctl_getversion(struct file *file, int __user *arg)
 {
-	struct inode *inode = file->f_path.dentry->d_inode;
+	struct inode *inode = file_inode(file);
 
 	return put_user(inode->i_generation, arg);
 }
@@ -1317,7 +1317,7 @@
 	u64 new_size;
 	u64 old_size;
 	u64 devid = 1;
-	struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
+	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
 	struct btrfs_ioctl_vol_args *vol_args;
 	struct btrfs_trans_handle *trans;
 	struct btrfs_device *device = NULL;
@@ -1483,8 +1483,8 @@
 			goto out_drop_write;
 		}
 
-		src_inode = src.file->f_path.dentry->d_inode;
-		if (src_inode->i_sb != file->f_path.dentry->d_inode->i_sb) {
+		src_inode = file_inode(src.file);
+		if (src_inode->i_sb != file_inode(file)->i_sb) {
 			printk(KERN_INFO "btrfs: Snapshot src from "
 			       "another FS\n");
 			ret = -EINVAL;
@@ -1576,7 +1576,7 @@
 static noinline int btrfs_ioctl_subvol_getflags(struct file *file,
 						void __user *arg)
 {
-	struct inode *inode = fdentry(file)->d_inode;
+	struct inode *inode = file_inode(file);
 	struct btrfs_root *root = BTRFS_I(inode)->root;
 	int ret = 0;
 	u64 flags = 0;
@@ -1598,7 +1598,7 @@
 static noinline int btrfs_ioctl_subvol_setflags(struct file *file,
 					      void __user *arg)
 {
-	struct inode *inode = fdentry(file)->d_inode;
+	struct inode *inode = file_inode(file);
 	struct btrfs_root *root = BTRFS_I(inode)->root;
 	struct btrfs_trans_handle *trans;
 	u64 root_flags;
@@ -1892,7 +1892,7 @@
 	if (IS_ERR(args))
 		return PTR_ERR(args);
 
-	inode = fdentry(file)->d_inode;
+	inode = file_inode(file);
 	ret = search_ioctl(inode, args);
 	if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
 		ret = -EFAULT;
@@ -2002,7 +2002,7 @@
 	if (IS_ERR(args))
 		return PTR_ERR(args);
 
-	inode = fdentry(file)->d_inode;
+	inode = file_inode(file);
 
 	if (args->treeid == 0)
 		args->treeid = BTRFS_I(inode)->root->root_key.objectid;
@@ -2178,7 +2178,7 @@
 
 static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
 {
-	struct inode *inode = fdentry(file)->d_inode;
+	struct inode *inode = file_inode(file);
 	struct btrfs_root *root = BTRFS_I(inode)->root;
 	struct btrfs_ioctl_defrag_range_args *range;
 	int ret;
@@ -2237,7 +2237,7 @@
 			/* the rest are all set to zero by kzalloc */
 			range->len = (u64)-1;
 		}
-		ret = btrfs_defrag_file(fdentry(file)->d_inode, file,
+		ret = btrfs_defrag_file(file_inode(file), file,
 					range, 0, 0);
 		if (ret > 0)
 			ret = 0;
@@ -2285,7 +2285,7 @@
 
 static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg)
 {
-	struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
+	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
 	struct btrfs_ioctl_vol_args *vol_args;
 	int ret;
 
@@ -2408,7 +2408,7 @@
 static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
 				       u64 off, u64 olen, u64 destoff)
 {
-	struct inode *inode = fdentry(file)->d_inode;
+	struct inode *inode = file_inode(file);
 	struct btrfs_root *root = BTRFS_I(inode)->root;
 	struct fd src_file;
 	struct inode *src;
@@ -2454,7 +2454,7 @@
 	if (src_file.file->f_path.mnt != file->f_path.mnt)
 		goto out_fput;
 
-	src = src_file.file->f_dentry->d_inode;
+	src = file_inode(src_file.file);
 
 	ret = -EINVAL;
 	if (src == inode)
@@ -2816,7 +2816,7 @@
  */
 static long btrfs_ioctl_trans_start(struct file *file)
 {
-	struct inode *inode = fdentry(file)->d_inode;
+	struct inode *inode = file_inode(file);
 	struct btrfs_root *root = BTRFS_I(inode)->root;
 	struct btrfs_trans_handle *trans;
 	int ret;
@@ -2856,7 +2856,7 @@
 
 static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
 {
-	struct inode *inode = fdentry(file)->d_inode;
+	struct inode *inode = file_inode(file);
 	struct btrfs_root *root = BTRFS_I(inode)->root;
 	struct btrfs_root *new_root;
 	struct btrfs_dir_item *di;
@@ -3080,7 +3080,7 @@
  */
 long btrfs_ioctl_trans_end(struct file *file)
 {
-	struct inode *inode = fdentry(file)->d_inode;
+	struct inode *inode = file_inode(file);
 	struct btrfs_root *root = BTRFS_I(inode)->root;
 	struct btrfs_trans_handle *trans;
 
@@ -3142,7 +3142,7 @@
 
 static long btrfs_ioctl_scrub(struct file *file, void __user *arg)
 {
-	struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
+	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
 	struct btrfs_ioctl_scrub_args *sa;
 	int ret;
 
@@ -3433,7 +3433,7 @@
 
 static long btrfs_ioctl_balance(struct file *file, void __user *arg)
 {
-	struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
+	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
 	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct btrfs_ioctl_balance_args *bargs;
 	struct btrfs_balance_control *bctl;
@@ -3573,7 +3573,7 @@
 
 static long btrfs_ioctl_quota_ctl(struct file *file, void __user *arg)
 {
-	struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
+	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
 	struct btrfs_ioctl_quota_ctl_args *sa;
 	struct btrfs_trans_handle *trans = NULL;
 	int ret;
@@ -3632,7 +3632,7 @@
 
 static long btrfs_ioctl_qgroup_assign(struct file *file, void __user *arg)
 {
-	struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
+	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
 	struct btrfs_ioctl_qgroup_assign_args *sa;
 	struct btrfs_trans_handle *trans;
 	int ret;
@@ -3679,7 +3679,7 @@
 
 static long btrfs_ioctl_qgroup_create(struct file *file, void __user *arg)
 {
-	struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
+	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
 	struct btrfs_ioctl_qgroup_create_args *sa;
 	struct btrfs_trans_handle *trans;
 	int ret;
@@ -3725,7 +3725,7 @@
 
 static long btrfs_ioctl_qgroup_limit(struct file *file, void __user *arg)
 {
-	struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
+	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
 	struct btrfs_ioctl_qgroup_limit_args *sa;
 	struct btrfs_trans_handle *trans;
 	int ret;
@@ -3775,7 +3775,7 @@
 					    void __user *arg)
 {
 	struct btrfs_ioctl_received_subvol_args *sa = NULL;
-	struct inode *inode = fdentry(file)->d_inode;
+	struct inode *inode = file_inode(file);
 	struct btrfs_root *root = BTRFS_I(inode)->root;
 	struct btrfs_root_item *root_item = &root->root_item;
 	struct btrfs_trans_handle *trans;
@@ -3855,7 +3855,7 @@
 long btrfs_ioctl(struct file *file, unsigned int
 		cmd, unsigned long arg)
 {
-	struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
+	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
 	void __user *argp = (void __user *)arg;
 
 	switch (cmd) {
diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c
index 5445454..f80df6b 100644
--- a/fs/btrfs/send.c
+++ b/fs/btrfs/send.c
@@ -4542,7 +4542,7 @@
 	if (!capable(CAP_SYS_ADMIN))
 		return -EPERM;
 
-	send_root = BTRFS_I(fdentry(mnt_file)->d_inode)->root;
+	send_root = BTRFS_I(file_inode(mnt_file))->root;
 	fs_info = send_root->fs_info;
 
 	arg = memdup_user(arg_, sizeof(*arg));