1 files changed, 355 insertions, 0 deletions
diff --git a/fs/aufs/vfsub.h b/fs/aufs/vfsub.h
new file mode 100644
index 000000000000..43779266a991
--- /dev/null
+++ b/fs/aufs/vfsub.h
@@ -0,0 +1,355 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2005-2019 Junjiro R. Okajima
+ *
+ * This program, aufs is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/*
+ * sub-routines for VFS
+ */
+
+#ifndef __AUFS_VFSUB_H__
+#define __AUFS_VFSUB_H__
+
+#ifdef __KERNEL__
+
+#include <linux/fs.h>
+#include <linux/iversion.h>
+#include <linux/mount.h>
+#include <linux/posix_acl.h>
+#include <linux/xattr.h>
+#include "debug.h"
+
+/* copied from linux/fs/internal.h */
+/* todo: BAD approach!! */
+extern void __mnt_drop_write(struct vfsmount *);
+extern struct file *alloc_empty_file(int, const struct cred *);
+
+/* ---------------------------------------------------------------------- */
+
+/* lock subclass for lower inode */
+/* default MAX_LOCKDEP_SUBCLASSES(8) is not enough */
+/* reduce? gave up. */
+enum {
+	AuLsc_I_Begin = I_MUTEX_PARENT2, /* 5 */
+	AuLsc_I_PARENT,		/* lower inode, parent first */
+	AuLsc_I_PARENT2,	/* copyup dirs */
+	AuLsc_I_PARENT3,	/* copyup wh */
+	AuLsc_I_CHILD,
+	AuLsc_I_CHILD2,
+	AuLsc_I_End
+};
+
+/* to debug easier, do not make them inlined functions */
+#define MtxMustLock(mtx)	AuDebugOn(!mutex_is_locked(mtx))
+#define IMustLock(i)		AuDebugOn(!inode_is_locked(i))
+
+/* ---------------------------------------------------------------------- */
+
+static inline void vfsub_drop_nlink(struct inode *inode)
+{
+	AuDebugOn(!inode->i_nlink);
+	drop_nlink(inode);
+}
+
+static inline void vfsub_dead_dir(struct inode *inode)
+{
+	AuDebugOn(!S_ISDIR(inode->i_mode));
+	inode->i_flags |= S_DEAD;
+	clear_nlink(inode);
+}
+
+static inline int vfsub_native_ro(struct inode *inode)
+{
+	return sb_rdonly(inode->i_sb)
+		|| IS_RDONLY(inode)
+		/* || IS_APPEND(inode) */
+		|| IS_IMMUTABLE(inode);
+}
+
+#ifdef CONFIG_AUFS_BR_FUSE
+int vfsub_test_mntns(struct vfsmount *mnt, struct super_block *h_sb);
+#else
+AuStubInt0(vfsub_test_mntns, struct vfsmount *mnt, struct super_block *h_sb);
+#endif
+
+int vfsub_sync_filesystem(struct super_block *h_sb, int wait);
+
+/* ---------------------------------------------------------------------- */
+
+int vfsub_update_h_iattr(struct path *h_path, int *did);
+struct file *vfsub_dentry_open(struct path *path, int flags);
+struct file *vfsub_filp_open(const char *path, int oflags, int mode);
+struct au_branch;
+struct vfsub_aopen_args {
+	struct file		*file;
+	unsigned int		open_flag;
+	umode_t			create_mode;
+	struct au_branch	*br;
+};
+int vfsub_atomic_open(struct inode *dir, struct dentry *dentry,
+		      struct vfsub_aopen_args *args);
+int vfsub_kern_path(const char *name, unsigned int flags, struct path *path);
+
+struct dentry *vfsub_lookup_one_len_unlocked(const char *name,
+					     struct dentry *parent, int len);
+struct dentry *vfsub_lookup_one_len(const char *name, struct dentry *parent,
+				    int len);
+
+struct vfsub_lkup_one_args {
+	struct dentry **errp;
+	struct qstr *name;
+	struct dentry *parent;
+};
+
+static inline struct dentry *vfsub_lkup_one(struct qstr *name,
+					    struct dentry *parent)
+{
+	return vfsub_lookup_one_len(name->name, parent, name->len);
+}
+
+void vfsub_call_lkup_one(void *args);
+
+/* ---------------------------------------------------------------------- */
+
+static inline int vfsub_mnt_want_write(struct vfsmount *mnt)
+{
+	int err;
+
+	lockdep_off();
+	err = mnt_want_write(mnt);
+	lockdep_on();
+	return err;
+}
+
+static inline void vfsub_mnt_drop_write(struct vfsmount *mnt)
+{
+	lockdep_off();
+	mnt_drop_write(mnt);
+	lockdep_on();
+}
+
+#if 0 /* reserved */
+static inline void vfsub_mnt_drop_write_file(struct file *file)
+{
+	lockdep_off();
+	mnt_drop_write_file(file);
+	lockdep_on();
+}
+#endif
+
+/* ---------------------------------------------------------------------- */
+
+struct au_hinode;
+struct dentry *vfsub_lock_rename(struct dentry *d1, struct au_hinode *hdir1,
+				 struct dentry *d2, struct au_hinode *hdir2);
+void vfsub_unlock_rename(struct dentry *d1, struct au_hinode *hdir1,
+			 struct dentry *d2, struct au_hinode *hdir2);
+
+int vfsub_create(struct inode *dir, struct path *path, int mode,
+		 bool want_excl);
+int vfsub_symlink(struct inode *dir, struct path *path,
+		  const char *symname);
+int vfsub_mknod(struct inode *dir, struct path *path, int mode, dev_t dev);
+int vfsub_link(struct dentry *src_dentry, struct inode *dir,
+	       struct path *path, struct inode **delegated_inode);
+int vfsub_rename(struct inode *src_hdir, struct dentry *src_dentry,
+		 struct inode *hdir, struct path *path,
+		 struct inode **delegated_inode, unsigned int flags);
+int vfsub_mkdir(struct inode *dir, struct path *path, int mode);
+int vfsub_rmdir(struct inode *dir, struct path *path);
+
+/* ---------------------------------------------------------------------- */
+
+ssize_t vfsub_read_u(struct file *file, char __user *ubuf, size_t count,
+		     loff_t *ppos);
+ssize_t vfsub_read_k(struct file *file, void *kbuf, size_t count,
+			loff_t *ppos);
+ssize_t vfsub_write_u(struct file *file, const char __user *ubuf, size_t count,
+		      loff_t *ppos);
+ssize_t vfsub_write_k(struct file *file, void *kbuf, size_t count,
+		      loff_t *ppos);
+int vfsub_flush(struct file *file, fl_owner_t id);
+int vfsub_iterate_dir(struct file *file, struct dir_context *ctx);
+
+static inline loff_t vfsub_f_size_read(struct file *file)
+{
+	return i_size_read(file_inode(file));
+}
+
+static inline unsigned int vfsub_file_flags(struct file *file)
+{
+	unsigned int flags;
+
+	spin_lock(&file->f_lock);
+	flags = file->f_flags;
+	spin_unlock(&file->f_lock);
+
+	return flags;
+}
+
+static inline int vfsub_file_execed(struct file *file)
+{
+	/* todo: direct access f_flags */
+	return !!(vfsub_file_flags(file) & __FMODE_EXEC);
+}
+
+#if 0 /* reserved */
+static inline void vfsub_file_accessed(struct file *h_file)
+{
+	file_accessed(h_file);
+	vfsub_update_h_iattr(&h_file->f_path, /*did*/NULL); /*ignore*/
+}
+#endif
+
+#if 0 /* reserved */
+static inline void vfsub_touch_atime(struct vfsmount *h_mnt,
+				     struct dentry *h_dentry)
+{
+	struct path h_path = {
+		.dentry	= h_dentry,
+		.mnt	= h_mnt
+	};
+	touch_atime(&h_path);
+	vfsub_update_h_iattr(&h_path, /*did*/NULL); /*ignore*/
+}
+#endif
+
+static inline int vfsub_update_time(struct inode *h_inode,
+				    struct timespec64 *ts, int flags)
+{
+	return update_time(h_inode, ts, flags);
+	/* no vfsub_update_h_iattr() since we don't have struct path */
+}
+
+#ifdef CONFIG_FS_POSIX_ACL
+static inline int vfsub_acl_chmod(struct inode *h_inode, umode_t h_mode)
+{
+	int err;
+
+	err = posix_acl_chmod(h_inode, h_mode);
+	if (err == -EOPNOTSUPP)
+		err = 0;
+	return err;
+}
+#else
+AuStubInt0(vfsub_acl_chmod, struct inode *h_inode, umode_t h_mode);
+#endif
+
+long vfsub_splice_to(struct file *in, loff_t *ppos,
+		     struct pipe_inode_info *pipe, size_t len,
+		     unsigned int flags);
+long vfsub_splice_from(struct pipe_inode_info *pipe, struct file *out,
+		       loff_t *ppos, size_t len, unsigned int flags);
+
+static inline long vfsub_truncate(struct path *path, loff_t length)
+{
+	long err;
+
+	lockdep_off();
+	err = vfs_truncate(path, length);
+	lockdep_on();
+	return err;
+}
+
+int vfsub_trunc(struct path *h_path, loff_t length, unsigned int attr,
+		struct file *h_file);
+int vfsub_fsync(struct file *file, struct path *path, int datasync);
+
+/*
+ * re-use branch fs's ioctl(FICLONE) while aufs itself doesn't support such
+ * ioctl.
+ */
+static inline loff_t vfsub_clone_file_range(struct file *src, struct file *dst,
+					    loff_t len)
+{
+	loff_t err;
+
+	lockdep_off();
+	err = vfs_clone_file_range(src, 0, dst, 0, len, /*remap_flags*/0);
+	lockdep_on();
+
+	return err;
+}
+
+/* copy_file_range(2) is a systemcall */
+static inline ssize_t vfsub_copy_file_range(struct file *src, loff_t src_pos,
+					    struct file *dst, loff_t dst_pos,
+					    size_t len, unsigned int flags)
+{
+	ssize_t ssz;
+
+	lockdep_off();
+	ssz = vfs_copy_file_range(src, src_pos, dst, dst_pos, len, flags);
+	lockdep_on();
+
+	return ssz;
+}
+
+/* ---------------------------------------------------------------------- */
+
+static inline loff_t vfsub_llseek(struct file *file, loff_t offset, int origin)
+{
+	loff_t err;
+
+	lockdep_off();
+	err = vfs_llseek(file, offset, origin);
+	lockdep_on();
+	return err;
+}
+
+/* ---------------------------------------------------------------------- */
+
+int vfsub_sio_mkdir(struct inode *dir, struct path *path, int mode);
+int vfsub_sio_rmdir(struct inode *dir, struct path *path);
+int vfsub_sio_notify_change(struct path *path, struct iattr *ia,
+			    struct inode **delegated_inode);
+int vfsub_notify_change(struct path *path, struct iattr *ia,
+			struct inode **delegated_inode);
+int vfsub_unlink(struct inode *dir, struct path *path,
+		 struct inode **delegated_inode, int force);
+
+static inline int vfsub_getattr(const struct path *path, struct kstat *st)
+{
+	return vfs_getattr(path, st, STATX_BASIC_STATS, AT_STATX_SYNC_AS_STAT);
+}
+
+/* ---------------------------------------------------------------------- */
+
+static inline int vfsub_setxattr(struct dentry *dentry, const char *name,
+				 const void *value, size_t size, int flags)
+{
+	int err;
+
+	lockdep_off();
+	err = vfs_setxattr(dentry, name, value, size, flags);
+	lockdep_on();
+
+	return err;
+}
+
+static inline int vfsub_removexattr(struct dentry *dentry, const char *name)
+{
+	int err;
+
+	lockdep_off();
+	err = vfs_removexattr(dentry, name);
+	lockdep_on();
+
+	return err;
+}
+
+#endif /* __KERNEL__ */
+#endif /* __AUFS_VFSUB_H__ */