| /* 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 int fsnotify_name(__u32 mask, const void *data, int data_type, |
| struct inode *dir, const struct qstr *name, |
| u32 cookie) |
| { |
| if (atomic_long_read(&dir->i_sb->s_fsnotify_connectors) == 0) |
| return 0; |
| |
| return fsnotify(mask, data, data_type, dir, name, NULL, cookie); |
| } |
| |
| static inline void fsnotify_dirent(struct inode *dir, struct dentry *dentry, |
| __u32 mask) |
| { |
| fsnotify_name(mask, dentry, FSNOTIFY_EVENT_DENTRY, dir, &dentry->d_name, 0); |
| } |
| |
| static inline void fsnotify_inode(struct inode *inode, __u32 mask) |
| { |
| if (atomic_long_read(&inode->i_sb->s_fsnotify_connectors) == 0) |
| return; |
| |
| 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 (atomic_long_read(&inode->i_sb->s_fsnotify_connectors) == 0) |
| return 0; |
| |
| 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, dentry, FSNOTIFY_EVENT_DENTRY); |
| } |
| |
| 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; |
| __u32 rename_mask = FS_RENAME; |
| const struct qstr *new_name = &moved->d_name; |
| |
| if (isdir) { |
| old_dir_mask |= FS_ISDIR; |
| new_dir_mask |= FS_ISDIR; |
| rename_mask |= FS_ISDIR; |
| } |
| |
| /* Event with information about both old and new parent+name */ |
| fsnotify_name(rename_mask, moved, FSNOTIFY_EVENT_DENTRY, |
| old_dir, old_name, 0); |
| |
| fsnotify_name(old_dir_mask, source, FSNOTIFY_EVENT_INODE, |
| old_dir, old_name, fs_cookie); |
| fsnotify_name(new_dir_mask, source, FSNOTIFY_EVENT_INODE, |
| new_dir, 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 |
| * |
| * Caller must make sure that dentry->d_name is stable. |
| * Note: some filesystems (e.g. kernfs) leave @dentry negative and instantiate |
| * ->d_inode later |
| */ |
| static inline void fsnotify_create(struct inode *dir, struct dentry *dentry) |
| { |
| audit_inode_child(dir, dentry, AUDIT_TYPE_CHILD_CREATE); |
| |
| fsnotify_dirent(dir, dentry, FS_CREATE); |
| } |
| |
| /* |
| * fsnotify_link - new hardlink in 'inode' directory |
| * |
| * Caller must make sure that new_dentry->d_name is stable. |
| * 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(FS_CREATE, inode, FSNOTIFY_EVENT_INODE, |
| dir, &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 |
| * |
| * Caller must make sure that dentry->d_name is stable. |
| * Note: some filesystems (e.g. kernfs) leave @dentry negative and instantiate |
| * ->d_inode later |
| */ |
| static inline void fsnotify_mkdir(struct inode *dir, struct dentry *dentry) |
| { |
| audit_inode_child(dir, dentry, AUDIT_TYPE_CHILD_CREATE); |
| |
| fsnotify_dirent(dir, 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); |
| } |
| |
| static inline int fsnotify_sb_error(struct super_block *sb, struct inode *inode, |
| int error) |
| { |
| struct fs_error_report report = { |
| .error = error, |
| .inode = inode, |
| .sb = sb, |
| }; |
| |
| return fsnotify(FS_ERROR, &report, FSNOTIFY_EVENT_ERROR, |
| NULL, NULL, NULL, 0); |
| } |
| |
| #endif /* _LINUX_FS_NOTIFY_H */ |