include/linux/fsnotify.h - linux - Git at Google

 /* SPDX-License-Identifier: GPL-2.0 */
 #ifndef _LINUX_FS_NOTIFY_H
 #define _LINUX_FS_NOTIFY_H

 /*
  * include/linux/fsnotify.h - generic hooks for filesystem notification, to
  * reduce in-source duplication from both dnotify and inotify.
  *
  * We don't compile any of this away in some complicated menagerie of ifdefs.
  * Instead, we rely on the code inside to optimize away as needed.
  *
  * (C) Copyright 2005 Robert Love
  */

 #include <linux/fsnotify_backend.h>
 #include <linux/audit.h>
 #include <linux/slab.h>
 #include <linux/bug.h>

 /*
  * Notify this @dir inode about a change in a child directory entry.
  * The directory entry may have turned positive or negative or its inode may
  * have changed (i.e. renamed over).
  *
  * Unlike fsnotify_parent(), the event will be reported regardless of the
  * FS_EVENT_ON_CHILD mask on the parent inode and will not be reported if only
  * the child is interested and not the parent.
  */
 static inline void fsnotify_name(struct inode *dir, __u32 mask,
 				 struct inode *child,
 				 const struct qstr *name, u32 cookie)
 {
 	fsnotify(mask, child, FSNOTIFY_EVENT_INODE, dir, name, NULL, cookie);
 }

 static inline void fsnotify_dirent(struct inode *dir, struct dentry *dentry,
 				   __u32 mask)
 {
 	fsnotify_name(dir, mask, d_inode(dentry), &dentry->d_name, 0);
 }

 static inline void fsnotify_inode(struct inode *inode, __u32 mask)
 {
 	if (S_ISDIR(inode->i_mode))
 		mask |= FS_ISDIR;

 	fsnotify(mask, inode, FSNOTIFY_EVENT_INODE, NULL, NULL, inode, 0);
 }

 /* Notify this dentry's parent about a child's events. */
 static inline int fsnotify_parent(struct dentry *dentry, __u32 mask,
 				  const void *data, int data_type)
 {
 	struct inode *inode = d_inode(dentry);

 	if (S_ISDIR(inode->i_mode)) {
 		mask |= FS_ISDIR;

 		/* sb/mount marks are not interested in name of directory */
 		if (!(dentry->d_flags & DCACHE_FSNOTIFY_PARENT_WATCHED))
 			goto notify_child;
 	}

 	/* disconnected dentry cannot notify parent */
 	if (IS_ROOT(dentry))
 		goto notify_child;

 	return __fsnotify_parent(dentry, mask, data, data_type);

 notify_child:
 	return fsnotify(mask, data, data_type, NULL, NULL, inode, 0);
 }

 /*
  * Simple wrappers to consolidate calls to fsnotify_parent() when an event
  * is on a file/dentry.
  */
 static inline void fsnotify_dentry(struct dentry *dentry, __u32 mask)
 {
 	fsnotify_parent(dentry, mask, d_inode(dentry), FSNOTIFY_EVENT_INODE);
 }

 static inline int fsnotify_file(struct file *file, __u32 mask)
 {
 	const struct path *path = &file->f_path;

 	if (file->f_mode & FMODE_NONOTIFY)
 		return 0;

 	return fsnotify_parent(path->dentry, mask, path, FSNOTIFY_EVENT_PATH);
 }

 /* Simple call site for access decisions */
 static inline int fsnotify_perm(struct file *file, int mask)
 {
 	int ret;
 	__u32 fsnotify_mask = 0;

 	if (!(mask & (MAY_READ | MAY_OPEN)))
 		return 0;

 	if (mask & MAY_OPEN) {
 		fsnotify_mask = FS_OPEN_PERM;

 		if (file->f_flags & __FMODE_EXEC) {
 			ret = fsnotify_file(file, FS_OPEN_EXEC_PERM);

 			if (ret)
 				return ret;
 		}
 	} else if (mask & MAY_READ) {
 		fsnotify_mask = FS_ACCESS_PERM;
 	}

 	return fsnotify_file(file, fsnotify_mask);
 }

 /*
  * fsnotify_link_count - inode's link count changed
  */
 static inline void fsnotify_link_count(struct inode *inode)
 {
 	fsnotify_inode(inode, FS_ATTRIB);
 }

 /*
  * fsnotify_move - file old_name at old_dir was moved to new_name at new_dir
  */
 static inline void fsnotify_move(struct inode *old_dir, struct inode *new_dir,
 				 const struct qstr *old_name,
 				 int isdir, struct inode *target,
 				 struct dentry *moved)
 {
 	struct inode *source = moved->d_inode;
 	u32 fs_cookie = fsnotify_get_cookie();
 	__u32 old_dir_mask = FS_MOVED_FROM;
 	__u32 new_dir_mask = FS_MOVED_TO;
 	const struct qstr *new_name = &moved->d_name;

 	if (old_dir == new_dir)
 		old_dir_mask |= FS_DN_RENAME;

 	if (isdir) {
 		old_dir_mask |= FS_ISDIR;
 		new_dir_mask |= FS_ISDIR;
 	}

 	fsnotify_name(old_dir, old_dir_mask, source, old_name, fs_cookie);
 	fsnotify_name(new_dir, new_dir_mask, source, new_name, fs_cookie);

 	if (target)
 		fsnotify_link_count(target);
 	fsnotify_inode(source, FS_MOVE_SELF);
 	audit_inode_child(new_dir, moved, AUDIT_TYPE_CHILD_CREATE);
 }

 /*
  * fsnotify_inode_delete - and inode is being evicted from cache, clean up is needed
  */
 static inline void fsnotify_inode_delete(struct inode *inode)
 {
 	__fsnotify_inode_delete(inode);
 }

 /*
  * fsnotify_vfsmount_delete - a vfsmount is being destroyed, clean up is needed
  */
 static inline void fsnotify_vfsmount_delete(struct vfsmount *mnt)
 {
 	__fsnotify_vfsmount_delete(mnt);
 }

 /*
  * fsnotify_inoderemove - an inode is going away
  */
 static inline void fsnotify_inoderemove(struct inode *inode)
 {
 	fsnotify_inode(inode, FS_DELETE_SELF);
 	__fsnotify_inode_delete(inode);
 }

 /*
  * fsnotify_create - 'name' was linked in
  */
 static inline void fsnotify_create(struct inode *inode, struct dentry *dentry)
 {
 	audit_inode_child(inode, dentry, AUDIT_TYPE_CHILD_CREATE);

 	fsnotify_dirent(inode, dentry, FS_CREATE);
 }

 /*
  * fsnotify_link - new hardlink in 'inode' directory
  * Note: We have to pass also the linked inode ptr as some filesystems leave
  *   new_dentry->d_inode NULL and instantiate inode pointer later
  */
 static inline void fsnotify_link(struct inode *dir, struct inode *inode,
 				 struct dentry *new_dentry)
 {
 	fsnotify_link_count(inode);
 	audit_inode_child(dir, new_dentry, AUDIT_TYPE_CHILD_CREATE);

 	fsnotify_name(dir, FS_CREATE, inode, &new_dentry->d_name, 0);
 }

 /*
  * fsnotify_unlink - 'name' was unlinked
  *
  * Caller must make sure that dentry->d_name is stable.
  */
 static inline void fsnotify_unlink(struct inode *dir, struct dentry *dentry)
 {
 	/* Expected to be called before d_delete() */
 	WARN_ON_ONCE(d_is_negative(dentry));

 	fsnotify_dirent(dir, dentry, FS_DELETE);
 }

 /*
  * fsnotify_mkdir - directory 'name' was created
  */
 static inline void fsnotify_mkdir(struct inode *inode, struct dentry *dentry)
 {
 	audit_inode_child(inode, dentry, AUDIT_TYPE_CHILD_CREATE);

 	fsnotify_dirent(inode, dentry, FS_CREATE | FS_ISDIR);
 }

 /*
  * fsnotify_rmdir - directory 'name' was removed
  *
  * Caller must make sure that dentry->d_name is stable.
  */
 static inline void fsnotify_rmdir(struct inode *dir, struct dentry *dentry)
 {
 	/* Expected to be called before d_delete() */
 	WARN_ON_ONCE(d_is_negative(dentry));

 	fsnotify_dirent(dir, dentry, FS_DELETE | FS_ISDIR);
 }

 /*
  * fsnotify_access - file was read
  */
 static inline void fsnotify_access(struct file *file)
 {
 	fsnotify_file(file, FS_ACCESS);
 }

 /*
  * fsnotify_modify - file was modified
  */
 static inline void fsnotify_modify(struct file *file)
 {
 	fsnotify_file(file, FS_MODIFY);
 }

 /*
  * fsnotify_open - file was opened
  */
 static inline void fsnotify_open(struct file *file)
 {
 	__u32 mask = FS_OPEN;

 	if (file->f_flags & __FMODE_EXEC)
 		mask |= FS_OPEN_EXEC;

 	fsnotify_file(file, mask);
 }

 /*
  * fsnotify_close - file was closed
  */
 static inline void fsnotify_close(struct file *file)
 {
 	__u32 mask = (file->f_mode & FMODE_WRITE) ? FS_CLOSE_WRITE :
 						    FS_CLOSE_NOWRITE;

 	fsnotify_file(file, mask);
 }

 /*
  * fsnotify_xattr - extended attributes were changed
  */
 static inline void fsnotify_xattr(struct dentry *dentry)
 {
 	fsnotify_dentry(dentry, FS_ATTRIB);
 }

 /*
  * fsnotify_change - notify_change event.  file was modified and/or metadata
  * was changed.
  */
 static inline void fsnotify_change(struct dentry *dentry, unsigned int ia_valid)
 {
 	__u32 mask = 0;

 	if (ia_valid & ATTR_UID)
 		mask |= FS_ATTRIB;
 	if (ia_valid & ATTR_GID)
 		mask |= FS_ATTRIB;
 	if (ia_valid & ATTR_SIZE)
 		mask |= FS_MODIFY;

 	/* both times implies a utime(s) call */
 	if ((ia_valid & (ATTR_ATIME | ATTR_MTIME)) == (ATTR_ATIME | ATTR_MTIME))
 		mask |= FS_ATTRIB;
 	else if (ia_valid & ATTR_ATIME)
 		mask |= FS_ACCESS;
 	else if (ia_valid & ATTR_MTIME)
 		mask |= FS_MODIFY;

 	if (ia_valid & ATTR_MODE)
 		mask |= FS_ATTRIB;

 	if (mask)
 		fsnotify_dentry(dentry, mask);
 }

 #endif	/* _LINUX_FS_NOTIFY_H */
	/* SPDX-License-Identifier: GPL-2.0 */
	#ifndef _LINUX_FS_NOTIFY_H
	#define _LINUX_FS_NOTIFY_H

	/*
	* include/linux/fsnotify.h - generic hooks for filesystem notification, to
	* reduce in-source duplication from both dnotify and inotify.
	*
	* We don't compile any of this away in some complicated menagerie of ifdefs.
	* Instead, we rely on the code inside to optimize away as needed.
	*
	* (C) Copyright 2005 Robert Love
	*/

	#include <linux/fsnotify_backend.h>
	#include <linux/audit.h>
	#include <linux/slab.h>
	#include <linux/bug.h>

	/*
	* Notify this @dir inode about a change in a child directory entry.
	* The directory entry may have turned positive or negative or its inode may
	* have changed (i.e. renamed over).
	*
	* Unlike fsnotify_parent(), the event will be reported regardless of the
	* FS_EVENT_ON_CHILD mask on the parent inode and will not be reported if only
	* the child is interested and not the parent.
	*/
	static inline void fsnotify_name(struct inode *dir, __u32 mask,
	struct inode *child,
	const struct qstr *name, u32 cookie)
	{
	fsnotify(mask, child, FSNOTIFY_EVENT_INODE, dir, name, NULL, cookie);
	}

	static inline void fsnotify_dirent(struct inode dir, struct dentry dentry,
	__u32 mask)
	{
	fsnotify_name(dir, mask, d_inode(dentry), &dentry->d_name, 0);
	}

	static inline void fsnotify_inode(struct inode *inode, __u32 mask)
	{
	if (S_ISDIR(inode->i_mode))
	mask \|= FS_ISDIR;

	fsnotify(mask, inode, FSNOTIFY_EVENT_INODE, NULL, NULL, inode, 0);
	}

	/* Notify this dentry's parent about a child's events. */
	static inline int fsnotify_parent(struct dentry *dentry, __u32 mask,
	const void *data, int data_type)
	{
	struct inode *inode = d_inode(dentry);

	if (S_ISDIR(inode->i_mode)) {
	mask \|= FS_ISDIR;

	/* sb/mount marks are not interested in name of directory */
	if (!(dentry->d_flags & DCACHE_FSNOTIFY_PARENT_WATCHED))
	goto notify_child;
	}

	/* disconnected dentry cannot notify parent */
	if (IS_ROOT(dentry))
	goto notify_child;

	return __fsnotify_parent(dentry, mask, data, data_type);

	notify_child:
	return fsnotify(mask, data, data_type, NULL, NULL, inode, 0);
	}

	/*
	* Simple wrappers to consolidate calls to fsnotify_parent() when an event
	* is on a file/dentry.
	*/
	static inline void fsnotify_dentry(struct dentry *dentry, __u32 mask)
	{
	fsnotify_parent(dentry, mask, d_inode(dentry), FSNOTIFY_EVENT_INODE);
	}

	static inline int fsnotify_file(struct file *file, __u32 mask)
	{
	const struct path *path = &file->f_path;

	if (file->f_mode & FMODE_NONOTIFY)
	return 0;

	return fsnotify_parent(path->dentry, mask, path, FSNOTIFY_EVENT_PATH);
	}

	/* Simple call site for access decisions */
	static inline int fsnotify_perm(struct file *file, int mask)
	{
	int ret;
	__u32 fsnotify_mask = 0;

	if (!(mask & (MAY_READ \| MAY_OPEN)))
	return 0;

	if (mask & MAY_OPEN) {
	fsnotify_mask = FS_OPEN_PERM;

	if (file->f_flags & __FMODE_EXEC) {
	ret = fsnotify_file(file, FS_OPEN_EXEC_PERM);

	if (ret)
	return ret;
	}
	} else if (mask & MAY_READ) {
	fsnotify_mask = FS_ACCESS_PERM;
	}

	return fsnotify_file(file, fsnotify_mask);
	}

	/*
	* fsnotify_link_count - inode's link count changed
	*/
	static inline void fsnotify_link_count(struct inode *inode)
	{
	fsnotify_inode(inode, FS_ATTRIB);
	}

	/*
	* fsnotify_move - file old_name at old_dir was moved to new_name at new_dir
	*/
	static inline void fsnotify_move(struct inode old_dir, struct inode new_dir,
	const struct qstr *old_name,
	int isdir, struct inode *target,
	struct dentry *moved)
	{
	struct inode *source = moved->d_inode;
	u32 fs_cookie = fsnotify_get_cookie();
	__u32 old_dir_mask = FS_MOVED_FROM;
	__u32 new_dir_mask = FS_MOVED_TO;
	const struct qstr *new_name = &moved->d_name;

	if (old_dir == new_dir)
	old_dir_mask \|= FS_DN_RENAME;

	if (isdir) {
	old_dir_mask \|= FS_ISDIR;
	new_dir_mask \|= FS_ISDIR;
	}

	fsnotify_name(old_dir, old_dir_mask, source, old_name, fs_cookie);
	fsnotify_name(new_dir, new_dir_mask, source, new_name, fs_cookie);

	if (target)
	fsnotify_link_count(target);
	fsnotify_inode(source, FS_MOVE_SELF);
	audit_inode_child(new_dir, moved, AUDIT_TYPE_CHILD_CREATE);
	}

	/*
	* fsnotify_inode_delete - and inode is being evicted from cache, clean up is needed
	*/
	static inline void fsnotify_inode_delete(struct inode *inode)
	{
	__fsnotify_inode_delete(inode);
	}

	/*
	* fsnotify_vfsmount_delete - a vfsmount is being destroyed, clean up is needed
	*/
	static inline void fsnotify_vfsmount_delete(struct vfsmount *mnt)
	{
	__fsnotify_vfsmount_delete(mnt);
	}

	/*
	* fsnotify_inoderemove - an inode is going away
	*/
	static inline void fsnotify_inoderemove(struct inode *inode)
	{
	fsnotify_inode(inode, FS_DELETE_SELF);
	__fsnotify_inode_delete(inode);
	}

	/*
	* fsnotify_create - 'name' was linked in
	*/
	static inline void fsnotify_create(struct inode inode, struct dentry dentry)
	{
	audit_inode_child(inode, dentry, AUDIT_TYPE_CHILD_CREATE);

	fsnotify_dirent(inode, dentry, FS_CREATE);
	}

	/*
	* fsnotify_link - new hardlink in 'inode' directory
	* Note: We have to pass also the linked inode ptr as some filesystems leave
	* new_dentry->d_inode NULL and instantiate inode pointer later
	*/
	static inline void fsnotify_link(struct inode dir, struct inode inode,
	struct dentry *new_dentry)
	{
	fsnotify_link_count(inode);
	audit_inode_child(dir, new_dentry, AUDIT_TYPE_CHILD_CREATE);

	fsnotify_name(dir, FS_CREATE, inode, &new_dentry->d_name, 0);
	}

	/*
	* fsnotify_unlink - 'name' was unlinked
	*
	* Caller must make sure that dentry->d_name is stable.
	*/
	static inline void fsnotify_unlink(struct inode dir, struct dentry dentry)
	{
	/* Expected to be called before d_delete() */
	WARN_ON_ONCE(d_is_negative(dentry));

	fsnotify_dirent(dir, dentry, FS_DELETE);
	}

	/*
	* fsnotify_mkdir - directory 'name' was created
	*/
	static inline void fsnotify_mkdir(struct inode inode, struct dentry dentry)
	{
	audit_inode_child(inode, dentry, AUDIT_TYPE_CHILD_CREATE);

	fsnotify_dirent(inode, dentry, FS_CREATE \| FS_ISDIR);
	}

	/*
	* fsnotify_rmdir - directory 'name' was removed
	*
	* Caller must make sure that dentry->d_name is stable.
	*/
	static inline void fsnotify_rmdir(struct inode dir, struct dentry dentry)
	{
	/* Expected to be called before d_delete() */
	WARN_ON_ONCE(d_is_negative(dentry));

	fsnotify_dirent(dir, dentry, FS_DELETE \| FS_ISDIR);
	}

	/*
	* fsnotify_access - file was read
	*/
	static inline void fsnotify_access(struct file *file)
	{
	fsnotify_file(file, FS_ACCESS);
	}

	/*
	* fsnotify_modify - file was modified
	*/
	static inline void fsnotify_modify(struct file *file)
	{
	fsnotify_file(file, FS_MODIFY);
	}

	/*
	* fsnotify_open - file was opened
	*/
	static inline void fsnotify_open(struct file *file)
	{
	__u32 mask = FS_OPEN;

	if (file->f_flags & __FMODE_EXEC)
	mask \|= FS_OPEN_EXEC;

	fsnotify_file(file, mask);
	}

	/*
	* fsnotify_close - file was closed
	*/
	static inline void fsnotify_close(struct file *file)
	{
	__u32 mask = (file->f_mode & FMODE_WRITE) ? FS_CLOSE_WRITE :
	FS_CLOSE_NOWRITE;

	fsnotify_file(file, mask);
	}

	/*
	* fsnotify_xattr - extended attributes were changed
	*/
	static inline void fsnotify_xattr(struct dentry *dentry)
	{
	fsnotify_dentry(dentry, FS_ATTRIB);
	}

	/*
	* fsnotify_change - notify_change event. file was modified and/or metadata
	* was changed.
	*/
	static inline void fsnotify_change(struct dentry *dentry, unsigned int ia_valid)
	{
	__u32 mask = 0;

	if (ia_valid & ATTR_UID)
	mask \|= FS_ATTRIB;
	if (ia_valid & ATTR_GID)
	mask \|= FS_ATTRIB;
	if (ia_valid & ATTR_SIZE)
	mask \|= FS_MODIFY;

	/* both times implies a utime(s) call */
	if ((ia_valid & (ATTR_ATIME \| ATTR_MTIME)) == (ATTR_ATIME \| ATTR_MTIME))
	mask \|= FS_ATTRIB;
	else if (ia_valid & ATTR_ATIME)
	mask \|= FS_ACCESS;
	else if (ia_valid & ATTR_MTIME)
	mask \|= FS_MODIFY;

	if (ia_valid & ATTR_MODE)
	mask \|= FS_ATTRIB;

	if (mask)
	fsnotify_dentry(dentry, mask);
	}

	#endif /* _LINUX_FS_NOTIFY_H */