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This is never used, so can remove it. Signed-off-by: YueHaibing <yuehaibing@huawei.com> Signed-off-by: Jan Kara <jack@suse.cz> Message-Id: <20230725135528.25996-1-yuehaibing@huawei.com>
865 lines
29 KiB
C
865 lines
29 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
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/*
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* Filesystem access notification for Linux
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*
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* Copyright (C) 2008 Red Hat, Inc., Eric Paris <eparis@redhat.com>
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*/
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#ifndef __LINUX_FSNOTIFY_BACKEND_H
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#define __LINUX_FSNOTIFY_BACKEND_H
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#ifdef __KERNEL__
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#include <linux/idr.h> /* inotify uses this */
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#include <linux/fs.h> /* struct inode */
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#include <linux/list.h>
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#include <linux/path.h> /* struct path */
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#include <linux/spinlock.h>
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#include <linux/types.h>
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#include <linux/atomic.h>
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#include <linux/user_namespace.h>
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#include <linux/refcount.h>
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#include <linux/mempool.h>
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#include <linux/sched/mm.h>
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/*
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* IN_* from inotfy.h lines up EXACTLY with FS_*, this is so we can easily
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* convert between them. dnotify only needs conversion at watch creation
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* so no perf loss there. fanotify isn't defined yet, so it can use the
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* wholes if it needs more events.
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*/
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#define FS_ACCESS 0x00000001 /* File was accessed */
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#define FS_MODIFY 0x00000002 /* File was modified */
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#define FS_ATTRIB 0x00000004 /* Metadata changed */
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#define FS_CLOSE_WRITE 0x00000008 /* Writtable file was closed */
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#define FS_CLOSE_NOWRITE 0x00000010 /* Unwrittable file closed */
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#define FS_OPEN 0x00000020 /* File was opened */
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#define FS_MOVED_FROM 0x00000040 /* File was moved from X */
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#define FS_MOVED_TO 0x00000080 /* File was moved to Y */
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#define FS_CREATE 0x00000100 /* Subfile was created */
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#define FS_DELETE 0x00000200 /* Subfile was deleted */
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#define FS_DELETE_SELF 0x00000400 /* Self was deleted */
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#define FS_MOVE_SELF 0x00000800 /* Self was moved */
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#define FS_OPEN_EXEC 0x00001000 /* File was opened for exec */
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#define FS_UNMOUNT 0x00002000 /* inode on umount fs */
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#define FS_Q_OVERFLOW 0x00004000 /* Event queued overflowed */
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#define FS_ERROR 0x00008000 /* Filesystem Error (fanotify) */
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/*
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* FS_IN_IGNORED overloads FS_ERROR. It is only used internally by inotify
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* which does not support FS_ERROR.
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*/
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#define FS_IN_IGNORED 0x00008000 /* last inotify event here */
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#define FS_OPEN_PERM 0x00010000 /* open event in an permission hook */
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#define FS_ACCESS_PERM 0x00020000 /* access event in a permissions hook */
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#define FS_OPEN_EXEC_PERM 0x00040000 /* open/exec event in a permission hook */
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/*
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* Set on inode mark that cares about things that happen to its children.
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* Always set for dnotify and inotify.
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* Set on inode/sb/mount marks that care about parent/name info.
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*/
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#define FS_EVENT_ON_CHILD 0x08000000
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#define FS_RENAME 0x10000000 /* File was renamed */
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#define FS_DN_MULTISHOT 0x20000000 /* dnotify multishot */
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#define FS_ISDIR 0x40000000 /* event occurred against dir */
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#define FS_MOVE (FS_MOVED_FROM | FS_MOVED_TO)
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/*
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* Directory entry modification events - reported only to directory
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* where entry is modified and not to a watching parent.
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* The watching parent may get an FS_ATTRIB|FS_EVENT_ON_CHILD event
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* when a directory entry inside a child subdir changes.
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*/
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#define ALL_FSNOTIFY_DIRENT_EVENTS (FS_CREATE | FS_DELETE | FS_MOVE | FS_RENAME)
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#define ALL_FSNOTIFY_PERM_EVENTS (FS_OPEN_PERM | FS_ACCESS_PERM | \
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FS_OPEN_EXEC_PERM)
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/*
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* This is a list of all events that may get sent to a parent that is watching
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* with flag FS_EVENT_ON_CHILD based on fs event on a child of that directory.
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*/
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#define FS_EVENTS_POSS_ON_CHILD (ALL_FSNOTIFY_PERM_EVENTS | \
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FS_ACCESS | FS_MODIFY | FS_ATTRIB | \
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FS_CLOSE_WRITE | FS_CLOSE_NOWRITE | \
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FS_OPEN | FS_OPEN_EXEC)
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/*
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* This is a list of all events that may get sent with the parent inode as the
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* @to_tell argument of fsnotify().
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* It may include events that can be sent to an inode/sb/mount mark, but cannot
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* be sent to a parent watching children.
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*/
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#define FS_EVENTS_POSS_TO_PARENT (FS_EVENTS_POSS_ON_CHILD)
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/* Events that can be reported to backends */
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#define ALL_FSNOTIFY_EVENTS (ALL_FSNOTIFY_DIRENT_EVENTS | \
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FS_EVENTS_POSS_ON_CHILD | \
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FS_DELETE_SELF | FS_MOVE_SELF | \
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FS_UNMOUNT | FS_Q_OVERFLOW | FS_IN_IGNORED | \
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FS_ERROR)
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/* Extra flags that may be reported with event or control handling of events */
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#define ALL_FSNOTIFY_FLAGS (FS_ISDIR | FS_EVENT_ON_CHILD | FS_DN_MULTISHOT)
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#define ALL_FSNOTIFY_BITS (ALL_FSNOTIFY_EVENTS | ALL_FSNOTIFY_FLAGS)
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struct fsnotify_group;
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struct fsnotify_event;
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struct fsnotify_mark;
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struct fsnotify_event_private_data;
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struct fsnotify_fname;
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struct fsnotify_iter_info;
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struct mem_cgroup;
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/*
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* Each group much define these ops. The fsnotify infrastructure will call
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* these operations for each relevant group.
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*
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* handle_event - main call for a group to handle an fs event
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* @group: group to notify
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* @mask: event type and flags
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* @data: object that event happened on
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* @data_type: type of object for fanotify_data_XXX() accessors
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* @dir: optional directory associated with event -
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* if @file_name is not NULL, this is the directory that
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* @file_name is relative to
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* @file_name: optional file name associated with event
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* @cookie: inotify rename cookie
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* @iter_info: array of marks from this group that are interested in the event
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*
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* handle_inode_event - simple variant of handle_event() for groups that only
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* have inode marks and don't have ignore mask
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* @mark: mark to notify
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* @mask: event type and flags
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* @inode: inode that event happened on
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* @dir: optional directory associated with event -
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* if @file_name is not NULL, this is the directory that
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* @file_name is relative to.
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* Either @inode or @dir must be non-NULL.
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* @file_name: optional file name associated with event
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* @cookie: inotify rename cookie
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*
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* free_group_priv - called when a group refcnt hits 0 to clean up the private union
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* freeing_mark - called when a mark is being destroyed for some reason. The group
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* MUST be holding a reference on each mark and that reference must be
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* dropped in this function. inotify uses this function to send
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* userspace messages that marks have been removed.
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*/
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struct fsnotify_ops {
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int (*handle_event)(struct fsnotify_group *group, u32 mask,
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const void *data, int data_type, struct inode *dir,
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const struct qstr *file_name, u32 cookie,
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struct fsnotify_iter_info *iter_info);
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int (*handle_inode_event)(struct fsnotify_mark *mark, u32 mask,
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struct inode *inode, struct inode *dir,
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const struct qstr *file_name, u32 cookie);
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void (*free_group_priv)(struct fsnotify_group *group);
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void (*freeing_mark)(struct fsnotify_mark *mark, struct fsnotify_group *group);
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void (*free_event)(struct fsnotify_group *group, struct fsnotify_event *event);
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/* called on final put+free to free memory */
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void (*free_mark)(struct fsnotify_mark *mark);
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};
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/*
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* all of the information about the original object we want to now send to
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* a group. If you want to carry more info from the accessing task to the
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* listener this structure is where you need to be adding fields.
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*/
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struct fsnotify_event {
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struct list_head list;
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};
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/*
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* A group is a "thing" that wants to receive notification about filesystem
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* events. The mask holds the subset of event types this group cares about.
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* refcnt on a group is up to the implementor and at any moment if it goes 0
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* everything will be cleaned up.
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*/
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struct fsnotify_group {
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const struct fsnotify_ops *ops; /* how this group handles things */
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/*
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* How the refcnt is used is up to each group. When the refcnt hits 0
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* fsnotify will clean up all of the resources associated with this group.
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* As an example, the dnotify group will always have a refcnt=1 and that
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* will never change. Inotify, on the other hand, has a group per
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* inotify_init() and the refcnt will hit 0 only when that fd has been
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* closed.
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*/
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refcount_t refcnt; /* things with interest in this group */
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/* needed to send notification to userspace */
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spinlock_t notification_lock; /* protect the notification_list */
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struct list_head notification_list; /* list of event_holder this group needs to send to userspace */
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wait_queue_head_t notification_waitq; /* read() on the notification file blocks on this waitq */
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unsigned int q_len; /* events on the queue */
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unsigned int max_events; /* maximum events allowed on the list */
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/*
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* Valid fsnotify group priorities. Events are send in order from highest
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* priority to lowest priority. We default to the lowest priority.
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*/
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#define FS_PRIO_0 0 /* normal notifiers, no permissions */
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#define FS_PRIO_1 1 /* fanotify content based access control */
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#define FS_PRIO_2 2 /* fanotify pre-content access */
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unsigned int priority;
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bool shutdown; /* group is being shut down, don't queue more events */
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#define FSNOTIFY_GROUP_USER 0x01 /* user allocated group */
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#define FSNOTIFY_GROUP_DUPS 0x02 /* allow multiple marks per object */
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#define FSNOTIFY_GROUP_NOFS 0x04 /* group lock is not direct reclaim safe */
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int flags;
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unsigned int owner_flags; /* stored flags of mark_mutex owner */
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/* stores all fastpath marks assoc with this group so they can be cleaned on unregister */
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struct mutex mark_mutex; /* protect marks_list */
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atomic_t user_waits; /* Number of tasks waiting for user
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* response */
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struct list_head marks_list; /* all inode marks for this group */
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struct fasync_struct *fsn_fa; /* async notification */
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struct fsnotify_event *overflow_event; /* Event we queue when the
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* notification list is too
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* full */
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struct mem_cgroup *memcg; /* memcg to charge allocations */
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/* groups can define private fields here or use the void *private */
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union {
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void *private;
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#ifdef CONFIG_INOTIFY_USER
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struct inotify_group_private_data {
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spinlock_t idr_lock;
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struct idr idr;
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struct ucounts *ucounts;
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} inotify_data;
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#endif
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#ifdef CONFIG_FANOTIFY
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struct fanotify_group_private_data {
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/* Hash table of events for merge */
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struct hlist_head *merge_hash;
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/* allows a group to block waiting for a userspace response */
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struct list_head access_list;
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wait_queue_head_t access_waitq;
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int flags; /* flags from fanotify_init() */
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int f_flags; /* event_f_flags from fanotify_init() */
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struct ucounts *ucounts;
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mempool_t error_events_pool;
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} fanotify_data;
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#endif /* CONFIG_FANOTIFY */
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};
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};
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/*
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* These helpers are used to prevent deadlock when reclaiming inodes with
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* evictable marks of the same group that is allocating a new mark.
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*/
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static inline void fsnotify_group_lock(struct fsnotify_group *group)
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{
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mutex_lock(&group->mark_mutex);
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if (group->flags & FSNOTIFY_GROUP_NOFS)
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group->owner_flags = memalloc_nofs_save();
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}
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static inline void fsnotify_group_unlock(struct fsnotify_group *group)
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{
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if (group->flags & FSNOTIFY_GROUP_NOFS)
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memalloc_nofs_restore(group->owner_flags);
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mutex_unlock(&group->mark_mutex);
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}
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static inline void fsnotify_group_assert_locked(struct fsnotify_group *group)
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{
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WARN_ON_ONCE(!mutex_is_locked(&group->mark_mutex));
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if (group->flags & FSNOTIFY_GROUP_NOFS)
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WARN_ON_ONCE(!(current->flags & PF_MEMALLOC_NOFS));
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}
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/* When calling fsnotify tell it if the data is a path or inode */
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enum fsnotify_data_type {
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FSNOTIFY_EVENT_NONE,
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FSNOTIFY_EVENT_PATH,
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FSNOTIFY_EVENT_INODE,
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FSNOTIFY_EVENT_DENTRY,
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FSNOTIFY_EVENT_ERROR,
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};
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struct fs_error_report {
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int error;
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struct inode *inode;
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struct super_block *sb;
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};
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static inline struct inode *fsnotify_data_inode(const void *data, int data_type)
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{
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switch (data_type) {
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case FSNOTIFY_EVENT_INODE:
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return (struct inode *)data;
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case FSNOTIFY_EVENT_DENTRY:
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return d_inode(data);
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case FSNOTIFY_EVENT_PATH:
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return d_inode(((const struct path *)data)->dentry);
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case FSNOTIFY_EVENT_ERROR:
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return ((struct fs_error_report *)data)->inode;
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default:
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return NULL;
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}
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}
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static inline struct dentry *fsnotify_data_dentry(const void *data, int data_type)
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{
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switch (data_type) {
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case FSNOTIFY_EVENT_DENTRY:
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/* Non const is needed for dget() */
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return (struct dentry *)data;
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case FSNOTIFY_EVENT_PATH:
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return ((const struct path *)data)->dentry;
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default:
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return NULL;
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}
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}
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static inline const struct path *fsnotify_data_path(const void *data,
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int data_type)
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{
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switch (data_type) {
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case FSNOTIFY_EVENT_PATH:
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return data;
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default:
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return NULL;
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}
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}
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static inline struct super_block *fsnotify_data_sb(const void *data,
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int data_type)
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{
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switch (data_type) {
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case FSNOTIFY_EVENT_INODE:
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return ((struct inode *)data)->i_sb;
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case FSNOTIFY_EVENT_DENTRY:
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return ((struct dentry *)data)->d_sb;
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case FSNOTIFY_EVENT_PATH:
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return ((const struct path *)data)->dentry->d_sb;
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case FSNOTIFY_EVENT_ERROR:
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return ((struct fs_error_report *) data)->sb;
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default:
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return NULL;
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}
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}
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static inline struct fs_error_report *fsnotify_data_error_report(
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const void *data,
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int data_type)
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{
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switch (data_type) {
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case FSNOTIFY_EVENT_ERROR:
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return (struct fs_error_report *) data;
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default:
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return NULL;
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}
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}
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/*
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* Index to merged marks iterator array that correlates to a type of watch.
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* The type of watched object can be deduced from the iterator type, but not
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* the other way around, because an event can match different watched objects
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* of the same object type.
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* For example, both parent and child are watching an object of type inode.
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*/
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enum fsnotify_iter_type {
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FSNOTIFY_ITER_TYPE_INODE,
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FSNOTIFY_ITER_TYPE_VFSMOUNT,
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FSNOTIFY_ITER_TYPE_SB,
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FSNOTIFY_ITER_TYPE_PARENT,
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FSNOTIFY_ITER_TYPE_INODE2,
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FSNOTIFY_ITER_TYPE_COUNT
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};
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/* The type of object that a mark is attached to */
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enum fsnotify_obj_type {
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FSNOTIFY_OBJ_TYPE_ANY = -1,
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FSNOTIFY_OBJ_TYPE_INODE,
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FSNOTIFY_OBJ_TYPE_VFSMOUNT,
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FSNOTIFY_OBJ_TYPE_SB,
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FSNOTIFY_OBJ_TYPE_COUNT,
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FSNOTIFY_OBJ_TYPE_DETACHED = FSNOTIFY_OBJ_TYPE_COUNT
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};
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static inline bool fsnotify_valid_obj_type(unsigned int obj_type)
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{
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return (obj_type < FSNOTIFY_OBJ_TYPE_COUNT);
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}
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struct fsnotify_iter_info {
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struct fsnotify_mark *marks[FSNOTIFY_ITER_TYPE_COUNT];
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struct fsnotify_group *current_group;
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unsigned int report_mask;
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int srcu_idx;
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};
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static inline bool fsnotify_iter_should_report_type(
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struct fsnotify_iter_info *iter_info, int iter_type)
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{
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return (iter_info->report_mask & (1U << iter_type));
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}
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static inline void fsnotify_iter_set_report_type(
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struct fsnotify_iter_info *iter_info, int iter_type)
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{
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iter_info->report_mask |= (1U << iter_type);
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}
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static inline struct fsnotify_mark *fsnotify_iter_mark(
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struct fsnotify_iter_info *iter_info, int iter_type)
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{
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if (fsnotify_iter_should_report_type(iter_info, iter_type))
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return iter_info->marks[iter_type];
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return NULL;
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}
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static inline int fsnotify_iter_step(struct fsnotify_iter_info *iter, int type,
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struct fsnotify_mark **markp)
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{
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while (type < FSNOTIFY_ITER_TYPE_COUNT) {
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*markp = fsnotify_iter_mark(iter, type);
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if (*markp)
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break;
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type++;
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}
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return type;
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}
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#define FSNOTIFY_ITER_FUNCS(name, NAME) \
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static inline struct fsnotify_mark *fsnotify_iter_##name##_mark( \
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struct fsnotify_iter_info *iter_info) \
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{ \
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return fsnotify_iter_mark(iter_info, FSNOTIFY_ITER_TYPE_##NAME); \
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}
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FSNOTIFY_ITER_FUNCS(inode, INODE)
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FSNOTIFY_ITER_FUNCS(parent, PARENT)
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FSNOTIFY_ITER_FUNCS(vfsmount, VFSMOUNT)
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FSNOTIFY_ITER_FUNCS(sb, SB)
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#define fsnotify_foreach_iter_type(type) \
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for (type = 0; type < FSNOTIFY_ITER_TYPE_COUNT; type++)
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#define fsnotify_foreach_iter_mark_type(iter, mark, type) \
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for (type = 0; \
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type = fsnotify_iter_step(iter, type, &mark), \
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type < FSNOTIFY_ITER_TYPE_COUNT; \
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type++)
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/*
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* fsnotify_connp_t is what we embed in objects which connector can be attached
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* to. fsnotify_connp_t * is how we refer from connector back to object.
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*/
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struct fsnotify_mark_connector;
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typedef struct fsnotify_mark_connector __rcu *fsnotify_connp_t;
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/*
|
|
* Inode/vfsmount/sb point to this structure which tracks all marks attached to
|
|
* the inode/vfsmount/sb. The reference to inode/vfsmount/sb is held by this
|
|
* structure. We destroy this structure when there are no more marks attached
|
|
* to it. The structure is protected by fsnotify_mark_srcu.
|
|
*/
|
|
struct fsnotify_mark_connector {
|
|
spinlock_t lock;
|
|
unsigned short type; /* Type of object [lock] */
|
|
#define FSNOTIFY_CONN_FLAG_HAS_FSID 0x01
|
|
#define FSNOTIFY_CONN_FLAG_HAS_IREF 0x02
|
|
unsigned short flags; /* flags [lock] */
|
|
__kernel_fsid_t fsid; /* fsid of filesystem containing object */
|
|
union {
|
|
/* Object pointer [lock] */
|
|
fsnotify_connp_t *obj;
|
|
/* Used listing heads to free after srcu period expires */
|
|
struct fsnotify_mark_connector *destroy_next;
|
|
};
|
|
struct hlist_head list;
|
|
};
|
|
|
|
/*
|
|
* A mark is simply an object attached to an in core inode which allows an
|
|
* fsnotify listener to indicate they are either no longer interested in events
|
|
* of a type matching mask or only interested in those events.
|
|
*
|
|
* These are flushed when an inode is evicted from core and may be flushed
|
|
* when the inode is modified (as seen by fsnotify_access). Some fsnotify
|
|
* users (such as dnotify) will flush these when the open fd is closed and not
|
|
* at inode eviction or modification.
|
|
*
|
|
* Text in brackets is showing the lock(s) protecting modifications of a
|
|
* particular entry. obj_lock means either inode->i_lock or
|
|
* mnt->mnt_root->d_lock depending on the mark type.
|
|
*/
|
|
struct fsnotify_mark {
|
|
/* Mask this mark is for [mark->lock, group->mark_mutex] */
|
|
__u32 mask;
|
|
/* We hold one for presence in g_list. Also one ref for each 'thing'
|
|
* in kernel that found and may be using this mark. */
|
|
refcount_t refcnt;
|
|
/* Group this mark is for. Set on mark creation, stable until last ref
|
|
* is dropped */
|
|
struct fsnotify_group *group;
|
|
/* List of marks by group->marks_list. Also reused for queueing
|
|
* mark into destroy_list when it's waiting for the end of SRCU period
|
|
* before it can be freed. [group->mark_mutex] */
|
|
struct list_head g_list;
|
|
/* Protects inode / mnt pointers, flags, masks */
|
|
spinlock_t lock;
|
|
/* List of marks for inode / vfsmount [connector->lock, mark ref] */
|
|
struct hlist_node obj_list;
|
|
/* Head of list of marks for an object [mark ref] */
|
|
struct fsnotify_mark_connector *connector;
|
|
/* Events types and flags to ignore [mark->lock, group->mark_mutex] */
|
|
__u32 ignore_mask;
|
|
/* General fsnotify mark flags */
|
|
#define FSNOTIFY_MARK_FLAG_ALIVE 0x0001
|
|
#define FSNOTIFY_MARK_FLAG_ATTACHED 0x0002
|
|
/* inotify mark flags */
|
|
#define FSNOTIFY_MARK_FLAG_EXCL_UNLINK 0x0010
|
|
#define FSNOTIFY_MARK_FLAG_IN_ONESHOT 0x0020
|
|
/* fanotify mark flags */
|
|
#define FSNOTIFY_MARK_FLAG_IGNORED_SURV_MODIFY 0x0100
|
|
#define FSNOTIFY_MARK_FLAG_NO_IREF 0x0200
|
|
#define FSNOTIFY_MARK_FLAG_HAS_IGNORE_FLAGS 0x0400
|
|
unsigned int flags; /* flags [mark->lock] */
|
|
};
|
|
|
|
#ifdef CONFIG_FSNOTIFY
|
|
|
|
/* called from the vfs helpers */
|
|
|
|
/* main fsnotify call to send events */
|
|
extern int fsnotify(__u32 mask, const void *data, int data_type,
|
|
struct inode *dir, const struct qstr *name,
|
|
struct inode *inode, u32 cookie);
|
|
extern int __fsnotify_parent(struct dentry *dentry, __u32 mask, const void *data,
|
|
int data_type);
|
|
extern void __fsnotify_inode_delete(struct inode *inode);
|
|
extern void __fsnotify_vfsmount_delete(struct vfsmount *mnt);
|
|
extern void fsnotify_sb_delete(struct super_block *sb);
|
|
extern u32 fsnotify_get_cookie(void);
|
|
|
|
static inline __u32 fsnotify_parent_needed_mask(__u32 mask)
|
|
{
|
|
/* FS_EVENT_ON_CHILD is set on marks that want parent/name info */
|
|
if (!(mask & FS_EVENT_ON_CHILD))
|
|
return 0;
|
|
/*
|
|
* This object might be watched by a mark that cares about parent/name
|
|
* info, does it care about the specific set of events that can be
|
|
* reported with parent/name info?
|
|
*/
|
|
return mask & FS_EVENTS_POSS_TO_PARENT;
|
|
}
|
|
|
|
static inline int fsnotify_inode_watches_children(struct inode *inode)
|
|
{
|
|
/* FS_EVENT_ON_CHILD is set if the inode may care */
|
|
if (!(inode->i_fsnotify_mask & FS_EVENT_ON_CHILD))
|
|
return 0;
|
|
/* this inode might care about child events, does it care about the
|
|
* specific set of events that can happen on a child? */
|
|
return inode->i_fsnotify_mask & FS_EVENTS_POSS_ON_CHILD;
|
|
}
|
|
|
|
/*
|
|
* Update the dentry with a flag indicating the interest of its parent to receive
|
|
* filesystem events when those events happens to this dentry->d_inode.
|
|
*/
|
|
static inline void fsnotify_update_flags(struct dentry *dentry)
|
|
{
|
|
assert_spin_locked(&dentry->d_lock);
|
|
|
|
/*
|
|
* Serialisation of setting PARENT_WATCHED on the dentries is provided
|
|
* by d_lock. If inotify_inode_watched changes after we have taken
|
|
* d_lock, the following __fsnotify_update_child_dentry_flags call will
|
|
* find our entry, so it will spin until we complete here, and update
|
|
* us with the new state.
|
|
*/
|
|
if (fsnotify_inode_watches_children(dentry->d_parent->d_inode))
|
|
dentry->d_flags |= DCACHE_FSNOTIFY_PARENT_WATCHED;
|
|
else
|
|
dentry->d_flags &= ~DCACHE_FSNOTIFY_PARENT_WATCHED;
|
|
}
|
|
|
|
/* called from fsnotify listeners, such as fanotify or dnotify */
|
|
|
|
/* create a new group */
|
|
extern struct fsnotify_group *fsnotify_alloc_group(
|
|
const struct fsnotify_ops *ops,
|
|
int flags);
|
|
/* get reference to a group */
|
|
extern void fsnotify_get_group(struct fsnotify_group *group);
|
|
/* drop reference on a group from fsnotify_alloc_group */
|
|
extern void fsnotify_put_group(struct fsnotify_group *group);
|
|
/* group destruction begins, stop queuing new events */
|
|
extern void fsnotify_group_stop_queueing(struct fsnotify_group *group);
|
|
/* destroy group */
|
|
extern void fsnotify_destroy_group(struct fsnotify_group *group);
|
|
/* fasync handler function */
|
|
extern int fsnotify_fasync(int fd, struct file *file, int on);
|
|
/* Free event from memory */
|
|
extern void fsnotify_destroy_event(struct fsnotify_group *group,
|
|
struct fsnotify_event *event);
|
|
/* attach the event to the group notification queue */
|
|
extern int fsnotify_insert_event(struct fsnotify_group *group,
|
|
struct fsnotify_event *event,
|
|
int (*merge)(struct fsnotify_group *,
|
|
struct fsnotify_event *),
|
|
void (*insert)(struct fsnotify_group *,
|
|
struct fsnotify_event *));
|
|
|
|
static inline int fsnotify_add_event(struct fsnotify_group *group,
|
|
struct fsnotify_event *event,
|
|
int (*merge)(struct fsnotify_group *,
|
|
struct fsnotify_event *))
|
|
{
|
|
return fsnotify_insert_event(group, event, merge, NULL);
|
|
}
|
|
|
|
/* Queue overflow event to a notification group */
|
|
static inline void fsnotify_queue_overflow(struct fsnotify_group *group)
|
|
{
|
|
fsnotify_add_event(group, group->overflow_event, NULL);
|
|
}
|
|
|
|
static inline bool fsnotify_is_overflow_event(u32 mask)
|
|
{
|
|
return mask & FS_Q_OVERFLOW;
|
|
}
|
|
|
|
static inline bool fsnotify_notify_queue_is_empty(struct fsnotify_group *group)
|
|
{
|
|
assert_spin_locked(&group->notification_lock);
|
|
|
|
return list_empty(&group->notification_list);
|
|
}
|
|
|
|
extern bool fsnotify_notify_queue_is_empty(struct fsnotify_group *group);
|
|
/* return, but do not dequeue the first event on the notification queue */
|
|
extern struct fsnotify_event *fsnotify_peek_first_event(struct fsnotify_group *group);
|
|
/* return AND dequeue the first event on the notification queue */
|
|
extern struct fsnotify_event *fsnotify_remove_first_event(struct fsnotify_group *group);
|
|
/* Remove event queued in the notification list */
|
|
extern void fsnotify_remove_queued_event(struct fsnotify_group *group,
|
|
struct fsnotify_event *event);
|
|
|
|
/* functions used to manipulate the marks attached to inodes */
|
|
|
|
/*
|
|
* Canonical "ignore mask" including event flags.
|
|
*
|
|
* Note the subtle semantic difference from the legacy ->ignored_mask.
|
|
* ->ignored_mask traditionally only meant which events should be ignored,
|
|
* while ->ignore_mask also includes flags regarding the type of objects on
|
|
* which events should be ignored.
|
|
*/
|
|
static inline __u32 fsnotify_ignore_mask(struct fsnotify_mark *mark)
|
|
{
|
|
__u32 ignore_mask = mark->ignore_mask;
|
|
|
|
/* The event flags in ignore mask take effect */
|
|
if (mark->flags & FSNOTIFY_MARK_FLAG_HAS_IGNORE_FLAGS)
|
|
return ignore_mask;
|
|
|
|
/*
|
|
* Legacy behavior:
|
|
* - Always ignore events on dir
|
|
* - Ignore events on child if parent is watching children
|
|
*/
|
|
ignore_mask |= FS_ISDIR;
|
|
ignore_mask &= ~FS_EVENT_ON_CHILD;
|
|
ignore_mask |= mark->mask & FS_EVENT_ON_CHILD;
|
|
|
|
return ignore_mask;
|
|
}
|
|
|
|
/* Legacy ignored_mask - only event types to ignore */
|
|
static inline __u32 fsnotify_ignored_events(struct fsnotify_mark *mark)
|
|
{
|
|
return mark->ignore_mask & ALL_FSNOTIFY_EVENTS;
|
|
}
|
|
|
|
/*
|
|
* Check if mask (or ignore mask) should be applied depending if victim is a
|
|
* directory and whether it is reported to a watching parent.
|
|
*/
|
|
static inline bool fsnotify_mask_applicable(__u32 mask, bool is_dir,
|
|
int iter_type)
|
|
{
|
|
/* Should mask be applied to a directory? */
|
|
if (is_dir && !(mask & FS_ISDIR))
|
|
return false;
|
|
|
|
/* Should mask be applied to a child? */
|
|
if (iter_type == FSNOTIFY_ITER_TYPE_PARENT &&
|
|
!(mask & FS_EVENT_ON_CHILD))
|
|
return false;
|
|
|
|
return true;
|
|
}
|
|
|
|
/*
|
|
* Effective ignore mask taking into account if event victim is a
|
|
* directory and whether it is reported to a watching parent.
|
|
*/
|
|
static inline __u32 fsnotify_effective_ignore_mask(struct fsnotify_mark *mark,
|
|
bool is_dir, int iter_type)
|
|
{
|
|
__u32 ignore_mask = fsnotify_ignored_events(mark);
|
|
|
|
if (!ignore_mask)
|
|
return 0;
|
|
|
|
/* For non-dir and non-child, no need to consult the event flags */
|
|
if (!is_dir && iter_type != FSNOTIFY_ITER_TYPE_PARENT)
|
|
return ignore_mask;
|
|
|
|
ignore_mask = fsnotify_ignore_mask(mark);
|
|
if (!fsnotify_mask_applicable(ignore_mask, is_dir, iter_type))
|
|
return 0;
|
|
|
|
return ignore_mask & ALL_FSNOTIFY_EVENTS;
|
|
}
|
|
|
|
/* Get mask for calculating object interest taking ignore mask into account */
|
|
static inline __u32 fsnotify_calc_mask(struct fsnotify_mark *mark)
|
|
{
|
|
__u32 mask = mark->mask;
|
|
|
|
if (!fsnotify_ignored_events(mark))
|
|
return mask;
|
|
|
|
/* Interest in FS_MODIFY may be needed for clearing ignore mask */
|
|
if (!(mark->flags & FSNOTIFY_MARK_FLAG_IGNORED_SURV_MODIFY))
|
|
mask |= FS_MODIFY;
|
|
|
|
/*
|
|
* If mark is interested in ignoring events on children, the object must
|
|
* show interest in those events for fsnotify_parent() to notice it.
|
|
*/
|
|
return mask | mark->ignore_mask;
|
|
}
|
|
|
|
/* Get mask of events for a list of marks */
|
|
extern __u32 fsnotify_conn_mask(struct fsnotify_mark_connector *conn);
|
|
/* Calculate mask of events for a list of marks */
|
|
extern void fsnotify_recalc_mask(struct fsnotify_mark_connector *conn);
|
|
extern void fsnotify_init_mark(struct fsnotify_mark *mark,
|
|
struct fsnotify_group *group);
|
|
/* Find mark belonging to given group in the list of marks */
|
|
extern struct fsnotify_mark *fsnotify_find_mark(fsnotify_connp_t *connp,
|
|
struct fsnotify_group *group);
|
|
/* attach the mark to the object */
|
|
extern int fsnotify_add_mark(struct fsnotify_mark *mark,
|
|
fsnotify_connp_t *connp, unsigned int obj_type,
|
|
int add_flags, __kernel_fsid_t *fsid);
|
|
extern int fsnotify_add_mark_locked(struct fsnotify_mark *mark,
|
|
fsnotify_connp_t *connp,
|
|
unsigned int obj_type, int add_flags,
|
|
__kernel_fsid_t *fsid);
|
|
|
|
/* attach the mark to the inode */
|
|
static inline int fsnotify_add_inode_mark(struct fsnotify_mark *mark,
|
|
struct inode *inode,
|
|
int add_flags)
|
|
{
|
|
return fsnotify_add_mark(mark, &inode->i_fsnotify_marks,
|
|
FSNOTIFY_OBJ_TYPE_INODE, add_flags, NULL);
|
|
}
|
|
static inline int fsnotify_add_inode_mark_locked(struct fsnotify_mark *mark,
|
|
struct inode *inode,
|
|
int add_flags)
|
|
{
|
|
return fsnotify_add_mark_locked(mark, &inode->i_fsnotify_marks,
|
|
FSNOTIFY_OBJ_TYPE_INODE, add_flags,
|
|
NULL);
|
|
}
|
|
|
|
/* given a group and a mark, flag mark to be freed when all references are dropped */
|
|
extern void fsnotify_destroy_mark(struct fsnotify_mark *mark,
|
|
struct fsnotify_group *group);
|
|
/* detach mark from inode / mount list, group list, drop inode reference */
|
|
extern void fsnotify_detach_mark(struct fsnotify_mark *mark);
|
|
/* free mark */
|
|
extern void fsnotify_free_mark(struct fsnotify_mark *mark);
|
|
/* Wait until all marks queued for destruction are destroyed */
|
|
extern void fsnotify_wait_marks_destroyed(void);
|
|
/* Clear all of the marks of a group attached to a given object type */
|
|
extern void fsnotify_clear_marks_by_group(struct fsnotify_group *group,
|
|
unsigned int obj_type);
|
|
/* run all the marks in a group, and clear all of the vfsmount marks */
|
|
static inline void fsnotify_clear_vfsmount_marks_by_group(struct fsnotify_group *group)
|
|
{
|
|
fsnotify_clear_marks_by_group(group, FSNOTIFY_OBJ_TYPE_VFSMOUNT);
|
|
}
|
|
/* run all the marks in a group, and clear all of the inode marks */
|
|
static inline void fsnotify_clear_inode_marks_by_group(struct fsnotify_group *group)
|
|
{
|
|
fsnotify_clear_marks_by_group(group, FSNOTIFY_OBJ_TYPE_INODE);
|
|
}
|
|
/* run all the marks in a group, and clear all of the sn marks */
|
|
static inline void fsnotify_clear_sb_marks_by_group(struct fsnotify_group *group)
|
|
{
|
|
fsnotify_clear_marks_by_group(group, FSNOTIFY_OBJ_TYPE_SB);
|
|
}
|
|
extern void fsnotify_get_mark(struct fsnotify_mark *mark);
|
|
extern void fsnotify_put_mark(struct fsnotify_mark *mark);
|
|
extern void fsnotify_finish_user_wait(struct fsnotify_iter_info *iter_info);
|
|
extern bool fsnotify_prepare_user_wait(struct fsnotify_iter_info *iter_info);
|
|
|
|
static inline void fsnotify_init_event(struct fsnotify_event *event)
|
|
{
|
|
INIT_LIST_HEAD(&event->list);
|
|
}
|
|
|
|
#else
|
|
|
|
static inline int fsnotify(__u32 mask, const void *data, int data_type,
|
|
struct inode *dir, const struct qstr *name,
|
|
struct inode *inode, u32 cookie)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static inline int __fsnotify_parent(struct dentry *dentry, __u32 mask,
|
|
const void *data, int data_type)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static inline void __fsnotify_inode_delete(struct inode *inode)
|
|
{}
|
|
|
|
static inline void __fsnotify_vfsmount_delete(struct vfsmount *mnt)
|
|
{}
|
|
|
|
static inline void fsnotify_sb_delete(struct super_block *sb)
|
|
{}
|
|
|
|
static inline void fsnotify_update_flags(struct dentry *dentry)
|
|
{}
|
|
|
|
static inline u32 fsnotify_get_cookie(void)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static inline void fsnotify_unmount_inodes(struct super_block *sb)
|
|
{}
|
|
|
|
#endif /* CONFIG_FSNOTIFY */
|
|
|
|
#endif /* __KERNEL __ */
|
|
|
|
#endif /* __LINUX_FSNOTIFY_BACKEND_H */
|