diff options
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/fsnotify.h | 115 | ||||
| -rw-r--r-- | include/linux/fsnotify_backend.h | 177 |
2 files changed, 257 insertions, 35 deletions
diff --git a/include/linux/fsnotify.h b/include/linux/fsnotify.h index 00fbd5b245c..6c9ebefdac8 100644 --- a/include/linux/fsnotify.h +++ b/include/linux/fsnotify.h @@ -13,6 +13,7 @@ #include <linux/dnotify.h> #include <linux/inotify.h> +#include <linux/fsnotify_backend.h> #include <linux/audit.h> /* @@ -35,6 +36,16 @@ static inline void fsnotify_d_move(struct dentry *entry) } /* + * fsnotify_link_count - inode's link count changed + */ +static inline void fsnotify_link_count(struct inode *inode) +{ + inotify_inode_queue_event(inode, IN_ATTRIB, 0, NULL, NULL); + + fsnotify(inode, FS_ATTRIB, inode, FSNOTIFY_EVENT_INODE); +} + +/* * 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, @@ -43,28 +54,47 @@ static inline void fsnotify_move(struct inode *old_dir, struct inode *new_dir, { struct inode *source = moved->d_inode; u32 cookie = inotify_get_cookie(); + __u32 old_dir_mask = 0; + __u32 new_dir_mask = 0; - if (old_dir == new_dir) + if (old_dir == new_dir) { inode_dir_notify(old_dir, DN_RENAME); - else { + old_dir_mask = FS_DN_RENAME; + } else { inode_dir_notify(old_dir, DN_DELETE); + old_dir_mask = FS_DELETE; inode_dir_notify(new_dir, DN_CREATE); + new_dir_mask = FS_CREATE; } - if (isdir) + if (isdir) { isdir = IN_ISDIR; + old_dir_mask |= FS_IN_ISDIR; + new_dir_mask |= FS_IN_ISDIR; + } + + old_dir_mask |= FS_MOVED_FROM; + new_dir_mask |= FS_MOVED_TO; + inotify_inode_queue_event(old_dir, IN_MOVED_FROM|isdir,cookie,old_name, source); inotify_inode_queue_event(new_dir, IN_MOVED_TO|isdir, cookie, new_name, source); + fsnotify(old_dir, old_dir_mask, old_dir, FSNOTIFY_EVENT_INODE); + fsnotify(new_dir, new_dir_mask, new_dir, FSNOTIFY_EVENT_INODE); + if (target) { inotify_inode_queue_event(target, IN_DELETE_SELF, 0, NULL, NULL); inotify_inode_is_dead(target); + + /* this is really a link_count change not a removal */ + fsnotify_link_count(target); } if (source) { inotify_inode_queue_event(source, IN_MOVE_SELF, 0, NULL, NULL); + fsnotify(source, FS_MOVE_SELF, moved->d_inode, FSNOTIFY_EVENT_INODE); } audit_inode_child(new_name, moved, new_dir); } @@ -74,10 +104,12 @@ static inline void fsnotify_move(struct inode *old_dir, struct inode *new_dir, */ static inline void fsnotify_nameremove(struct dentry *dentry, int isdir) { + __u32 mask = FS_DELETE; + if (isdir) - isdir = IN_ISDIR; + mask |= FS_IN_ISDIR; dnotify_parent(dentry, DN_DELETE); - inotify_dentry_parent_queue_event(dentry, IN_DELETE|isdir, 0, dentry->d_name.name); + inotify_dentry_parent_queue_event(dentry, mask, 0, dentry->d_name.name); } /* @@ -87,14 +119,8 @@ static inline void fsnotify_inoderemove(struct inode *inode) { inotify_inode_queue_event(inode, IN_DELETE_SELF, 0, NULL, NULL); inotify_inode_is_dead(inode); -} -/* - * fsnotify_link_count - inode's link count changed - */ -static inline void fsnotify_link_count(struct inode *inode) -{ - inotify_inode_queue_event(inode, IN_ATTRIB, 0, NULL, NULL); + fsnotify(inode, FS_DELETE_SELF, inode, FSNOTIFY_EVENT_INODE); } /* @@ -106,6 +132,8 @@ static inline void fsnotify_create(struct inode *inode, struct dentry *dentry) inotify_inode_queue_event(inode, IN_CREATE, 0, dentry->d_name.name, dentry->d_inode); audit_inode_child(dentry->d_name.name, dentry, inode); + + fsnotify(inode, FS_CREATE, dentry->d_inode, FSNOTIFY_EVENT_INODE); } /* @@ -120,6 +148,8 @@ static inline void fsnotify_link(struct inode *dir, struct inode *inode, struct inode); fsnotify_link_count(inode); audit_inode_child(new_dentry->d_name.name, new_dentry, dir); + + fsnotify(dir, FS_CREATE, inode, FSNOTIFY_EVENT_INODE); } /* @@ -127,10 +157,14 @@ static inline void fsnotify_link(struct inode *dir, struct inode *inode, struct */ static inline void fsnotify_mkdir(struct inode *inode, struct dentry *dentry) { + __u32 mask = (FS_CREATE | FS_IN_ISDIR); + struct inode *d_inode = dentry->d_inode; + inode_dir_notify(inode, DN_CREATE); - inotify_inode_queue_event(inode, IN_CREATE | IN_ISDIR, 0, - dentry->d_name.name, dentry->d_inode); + inotify_inode_queue_event(inode, mask, 0, dentry->d_name.name, d_inode); audit_inode_child(dentry->d_name.name, dentry, inode); + + fsnotify(inode, mask, d_inode, FSNOTIFY_EVENT_INODE); } /* @@ -139,14 +173,16 @@ static inline void fsnotify_mkdir(struct inode *inode, struct dentry *dentry) static inline void fsnotify_access(struct dentry *dentry) { struct inode *inode = dentry->d_inode; - u32 mask = IN_ACCESS; + __u32 mask = FS_ACCESS; if (S_ISDIR(inode->i_mode)) - mask |= IN_ISDIR; + mask |= FS_IN_ISDIR; dnotify_parent(dentry, DN_ACCESS); inotify_dentry_parent_queue_event(dentry, mask, 0, dentry->d_name.name); inotify_inode_queue_event(inode, mask, 0, NULL, NULL); + + fsnotify(inode, mask, inode, FSNOTIFY_EVENT_INODE); } /* @@ -155,14 +191,16 @@ static inline void fsnotify_access(struct dentry *dentry) static inline void fsnotify_modify(struct dentry *dentry) { struct inode *inode = dentry->d_inode; - u32 mask = IN_MODIFY; + __u32 mask = FS_MODIFY; if (S_ISDIR(inode->i_mode)) - mask |= IN_ISDIR; + mask |= FS_IN_ISDIR; dnotify_parent(dentry, DN_MODIFY); inotify_dentry_parent_queue_event(dentry, mask, 0, dentry->d_name.name); inotify_inode_queue_event(inode, mask, 0, NULL, NULL); + + fsnotify(inode, mask, inode, FSNOTIFY_EVENT_INODE); } /* @@ -171,13 +209,15 @@ static inline void fsnotify_modify(struct dentry *dentry) static inline void fsnotify_open(struct dentry *dentry) { struct inode *inode = dentry->d_inode; - u32 mask = IN_OPEN; + __u32 mask = FS_OPEN; if (S_ISDIR(inode->i_mode)) - mask |= IN_ISDIR; + mask |= FS_IN_ISDIR; inotify_dentry_parent_queue_event(dentry, mask, 0, dentry->d_name.name); inotify_inode_queue_event(inode, mask, 0, NULL, NULL); + + fsnotify(inode, mask, inode, FSNOTIFY_EVENT_INODE); } /* @@ -189,13 +229,15 @@ static inline void fsnotify_close(struct file *file) struct inode *inode = dentry->d_inode; const char *name = dentry->d_name.name; fmode_t mode = file->f_mode; - u32 mask = (mode & FMODE_WRITE) ? IN_CLOSE_WRITE : IN_CLOSE_NOWRITE; + __u32 mask = (mode & FMODE_WRITE) ? FS_CLOSE_WRITE : FS_CLOSE_NOWRITE; if (S_ISDIR(inode->i_mode)) - mask |= IN_ISDIR; + mask |= FS_IN_ISDIR; inotify_dentry_parent_queue_event(dentry, mask, 0, name); inotify_inode_queue_event(inode, mask, 0, NULL, NULL); + + fsnotify(inode, mask, file, FSNOTIFY_EVENT_FILE); } /* @@ -204,13 +246,15 @@ static inline void fsnotify_close(struct file *file) static inline void fsnotify_xattr(struct dentry *dentry) { struct inode *inode = dentry->d_inode; - u32 mask = IN_ATTRIB; + __u32 mask = FS_ATTRIB; if (S_ISDIR(inode->i_mode)) - mask |= IN_ISDIR; + mask |= FS_IN_ISDIR; inotify_dentry_parent_queue_event(dentry, mask, 0, dentry->d_name.name); inotify_inode_queue_event(inode, mask, 0, NULL, NULL); + + fsnotify(inode, mask, inode, FSNOTIFY_EVENT_INODE); } /* @@ -221,34 +265,34 @@ static inline void fsnotify_change(struct dentry *dentry, unsigned int ia_valid) { struct inode *inode = dentry->d_inode; int dn_mask = 0; - u32 in_mask = 0; + __u32 in_mask = 0; if (ia_valid & ATTR_UID) { - in_mask |= IN_ATTRIB; + in_mask |= FS_ATTRIB; dn_mask |= DN_ATTRIB; } if (ia_valid & ATTR_GID) { - in_mask |= IN_ATTRIB; + in_mask |= FS_ATTRIB; dn_mask |= DN_ATTRIB; } if (ia_valid & ATTR_SIZE) { - in_mask |= IN_MODIFY; + in_mask |= FS_MODIFY; dn_mask |= DN_MODIFY; } /* both times implies a utime(s) call */ if ((ia_valid & (ATTR_ATIME | ATTR_MTIME)) == (ATTR_ATIME | ATTR_MTIME)) { - in_mask |= IN_ATTRIB; + in_mask |= FS_ATTRIB; dn_mask |= DN_ATTRIB; } else if (ia_valid & ATTR_ATIME) { - in_mask |= IN_ACCESS; + in_mask |= FS_ACCESS; dn_mask |= DN_ACCESS; } else if (ia_valid & ATTR_MTIME) { - in_mask |= IN_MODIFY; + in_mask |= FS_MODIFY; dn_mask |= DN_MODIFY; } if (ia_valid & ATTR_MODE) { - in_mask |= IN_ATTRIB; + in_mask |= FS_ATTRIB; dn_mask |= DN_ATTRIB; } @@ -256,14 +300,15 @@ static inline void fsnotify_change(struct dentry *dentry, unsigned int ia_valid) dnotify_parent(dentry, dn_mask); if (in_mask) { if (S_ISDIR(inode->i_mode)) - in_mask |= IN_ISDIR; + in_mask |= FS_IN_ISDIR; inotify_inode_queue_event(inode, in_mask, 0, NULL, NULL); inotify_dentry_parent_queue_event(dentry, in_mask, 0, dentry->d_name.name); + fsnotify(inode, in_mask, inode, FSNOTIFY_EVENT_INODE); } } -#ifdef CONFIG_INOTIFY /* inotify helpers */ +#if defined(CONFIG_INOTIFY) || defined(CONFIG_FSNOTIFY) /* notify helpers */ /* * fsnotify_oldname_init - save off the old filename before we change it @@ -281,7 +326,7 @@ static inline void fsnotify_oldname_free(const char *old_name) kfree(old_name); } -#else /* CONFIG_INOTIFY */ +#else /* CONFIG_INOTIFY || CONFIG_FSNOTIFY */ static inline const char *fsnotify_oldname_init(const char *name) { diff --git a/include/linux/fsnotify_backend.h b/include/linux/fsnotify_backend.h new file mode 100644 index 00000000000..1a55718b38a --- /dev/null +++ b/include/linux/fsnotify_backend.h @@ -0,0 +1,177 @@ +/* + * Filesystem access notification for Linux + * + * Copyright (C) 2008 Red Hat, Inc., Eric Paris <eparis@redhat.com> + */ + +#ifndef __LINUX_FSNOTIFY_BACKEND_H +#define __LINUX_FSNOTIFY_BACKEND_H + +#ifdef __KERNEL__ + +#include <linux/fs.h> /* struct inode */ +#include <linux/list.h> +#include <linux/path.h> /* struct path */ +#include <linux/spinlock.h> +#include <linux/types.h> + +#include <asm/atomic.h> + +/* + * IN_* from inotfy.h lines up EXACTLY with FS_*, this is so we can easily + * convert between them. dnotify only needs conversion at watch creation + * so no perf loss there. fanotify isn't defined yet, so it can use the + * wholes if it needs more events. + */ +#define FS_ACCESS 0x00000001 /* File was accessed */ +#define FS_MODIFY 0x00000002 /* File was modified */ +#define FS_ATTRIB 0x00000004 /* Metadata changed */ +#define FS_CLOSE_WRITE 0x00000008 /* Writtable file was closed */ +#define FS_CLOSE_NOWRITE 0x00000010 /* Unwrittable file closed */ +#define FS_OPEN 0x00000020 /* File was opened */ +#define FS_MOVED_FROM 0x00000040 /* File was moved from X */ +#define FS_MOVED_TO 0x00000080 /* File was moved to Y */ +#define FS_CREATE 0x00000100 /* Subfile was created */ +#define FS_DELETE 0x00000200 /* Subfile was deleted */ +#define FS_DELETE_SELF 0x00000400 /* Self was deleted */ +#define FS_MOVE_SELF 0x00000800 /* Self was moved */ + +#define FS_UNMOUNT 0x00002000 /* inode on umount fs */ +#define FS_Q_OVERFLOW 0x00004000 /* Event queued overflowed */ +#define FS_IN_IGNORED 0x00008000 /* last inotify event here */ + +#define FS_IN_ISDIR 0x40000000 /* event occurred against dir */ +#define FS_IN_ONESHOT 0x80000000 /* only send event once */ + +#define FS_DN_RENAME 0x10000000 /* file renamed */ +#define FS_DN_MULTISHOT 0x20000000 /* dnotify multishot */ + +struct fsnotify_group; +struct fsnotify_event; + +/* + * Each group much define these ops. The fsnotify infrastructure will call + * these operations for each relevant group. + * + * handle_event - main call for a group to handle an fs event + * free_group_priv - called when a group refcnt hits 0 to clean up the private union + */ +struct fsnotify_ops { + int (*handle_event)(struct fsnotify_group *group, struct fsnotify_event *event); + void (*free_group_priv)(struct fsnotify_group *group); +}; + +/* + * A group is a "thing" that wants to receive notification about filesystem + * events. The mask holds the subset of event types this group cares about. + * refcnt on a group is up to the implementor and at any moment if it goes 0 + * everything will be cleaned up. + */ +struct fsnotify_group { + /* + * global list of all groups receiving events from fsnotify. + * anchored by fsnotify_groups and protected by either fsnotify_grp_mutex + * or fsnotify_grp_srcu depending on write vs read. + */ + struct list_head group_list; + + /* + * Defines all of the event types in which this group is interested. + * This mask is a bitwise OR of the FS_* events from above. Each time + * this mask changes for a group (if it changes) the correct functions + * must be called to update the global structures which indicate global + * interest in event types. + */ + __u32 mask; + + /* + * How the refcnt is used is up to each group. When the refcnt hits 0 + * fsnotify will clean up all of the resources associated with this group. + * As an example, the dnotify group will always have a refcnt=1 and that + * will never change. Inotify, on the other hand, has a group per + * inotify_init() and the refcnt will hit 0 only when that fd has been + * closed. + */ + atomic_t refcnt; /* things with interest in this group */ + unsigned int group_num; /* simply prevents accidental group collision */ + + const struct fsnotify_ops *ops; /* how this group handles things */ + + /* prevents double list_del of group_list. protected by global fsnotify_gr_mutex */ + bool on_group_list; + + /* groups can define private fields here or use the void *private */ + union { + void *private; + }; +}; + +/* + * all of the information about the original object we want to now send to + * a group. If you want to carry more info from the accessing task to the + * listener this structure is where you need to be adding fields. + */ +struct fsnotify_event { + spinlock_t lock; /* protection for the associated event_holder and private_list */ + /* to_tell may ONLY be dereferenced during handle_event(). */ + struct inode *to_tell; /* either the inode the event happened to or its parent */ + /* + * depending on the event type we should have either a path or inode + * We hold a reference on path, but NOT on inode. Since we have the ref on + * the path, it may be dereferenced at any point during this object's + * lifetime. That reference is dropped when this object's refcnt hits + * 0. If this event contains an inode instead of a path, the inode may + * ONLY be used during handle_event(). + */ + union { + struct path path; + struct inode *inode; + }; +/* when calling fsnotify tell it if the data is a path or inode */ +#define FSNOTIFY_EVENT_NONE 0 +#define FSNOTIFY_EVENT_PATH 1 +#define FSNOTIFY_EVENT_INODE 2 +#define FSNOTIFY_EVENT_FILE 3 + int data_type; /* which of the above union we have */ + atomic_t refcnt; /* how many groups still are using/need to send this event */ + __u32 mask; /* the type of access, bitwise OR for FS_* event types */ +}; + +#ifdef CONFIG_FSNOTIFY + +/* called from the vfs helpers */ + +/* main fsnotify call to send events */ +extern void fsnotify(struct inode *to_tell, __u32 mask, void *data, int data_is); + + +/* called from fsnotify listeners, such as fanotify or dnotify */ + +/* must call when a group changes its ->mask */ +extern void fsnotify_recalc_global_mask(void); +/* get a reference to an existing or create a new group */ +extern struct fsnotify_group *fsnotify_obtain_group(unsigned int group_num, + __u32 mask, + const struct fsnotify_ops *ops); +/* drop reference on a group from fsnotify_obtain_group */ +extern void fsnotify_put_group(struct fsnotify_group *group); + +/* take a reference to an event */ +extern void fsnotify_get_event(struct fsnotify_event *event); +extern void fsnotify_put_event(struct fsnotify_event *event); +/* find private data previously attached to an event */ +extern struct fsnotify_event_private_data *fsnotify_get_priv_from_event(struct fsnotify_group *group, + struct fsnotify_event *event); + +/* put here because inotify does some weird stuff when destroying watches */ +extern struct fsnotify_event *fsnotify_create_event(struct inode *to_tell, __u32 mask, + void *data, int data_is); +#else + +static inline void fsnotify(struct inode *to_tell, __u32 mask, void *data, int data_is) +{} +#endif /* CONFIG_FSNOTIFY */ + +#endif /* __KERNEL __ */ + +#endif /* __LINUX_FSNOTIFY_BACKEND_H */ |