Commit 25b229df authored by Al Viro's avatar Al Viro
Browse files

fsnotify(): switch to passing const struct qstr * for file_name 



Note that in fnsotify_move() and fsnotify_link() we are guaranteed
that dentry->d_name won't change during the fsnotify() evaluation
(by having the parent directory locked exclusive), so we don't
need to fetch dentry->d_name.name in the callers.  In fsnotify_dirent()
the same stability of dentry->d_name is also true, but it's a bit
more convoluted - there is one callchain (devpts_pty_new() ->
fsnotify_create() -> fsnotify_dirent()) where the parent is _not_
locked, but on devpts ->d_name of everything is unchanging; it
has neither explicit nor implicit renames.

Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent f4ec3a3d

fs/kernfs/file.c

+4 −2
Original line number Diff line number Diff line
@@ -885,6 +885,7 @@ repeat: 
	list_for_each_entry(info, &kernfs_root(kn)->supers, node) {

		struct kernfs_node *parent;

		struct inode *inode;

		struct qstr name;



		/*

		 * We want fsnotify_modify() on @kn but as the
@@ -896,6 +897,7 @@ repeat: 
		if (!inode)

			continue;



		name = (struct qstr)QSTR_INIT(kn->name, strlen(kn->name));

		parent = kernfs_get_parent(kn);

		if (parent) {

			struct inode *p_inode;
@@ -903,7 +905,7 @@ repeat: 
			p_inode = ilookup(info->sb, parent->id.ino);

			if (p_inode) {

				fsnotify(p_inode, FS_MODIFY | FS_EVENT_ON_CHILD,

					 inode, FSNOTIFY_EVENT_INODE, kn->name, 0);

					 inode, FSNOTIFY_EVENT_INODE, &name, 0);

				iput(p_inode);

			}
@@ -911,7 +913,7 @@ repeat: 
		}



		fsnotify(inode, FS_MODIFY, inode, FSNOTIFY_EVENT_INODE,

			 kn->name, 0);

			 &name, 0);

		iput(inode);

	}

fs/notify/fsnotify.c

+4 −4
Original line number Diff line number Diff line
@@ -179,10 +179,10 @@ int __fsnotify_parent(const struct path *path, struct dentry *dentry, __u32 mask 
		take_dentry_name_snapshot(&name, dentry);

		if (path)

			ret = fsnotify(p_inode, mask, path, FSNOTIFY_EVENT_PATH,

				       name.name.name, 0);

				       &name.name, 0);

		else

			ret = fsnotify(p_inode, mask, dentry->d_inode, FSNOTIFY_EVENT_INODE,

				       name.name.name, 0);

				       &name.name, 0);

		release_dentry_name_snapshot(&name);

	}
@@ -325,7 +325,7 @@ static void fsnotify_iter_next(struct fsnotify_iter_info *iter_info) 
 * notification event in whatever means they feel necessary.

 */

int fsnotify(struct inode *to_tell, __u32 mask, const void *data, int data_is,

	     const unsigned char *file_name, u32 cookie)

	     const struct qstr *file_name, u32 cookie)

{

	struct fsnotify_iter_info iter_info = {};

	struct super_block *sb = to_tell->i_sb;
@@ -379,7 +379,7 @@ int fsnotify(struct inode *to_tell, __u32 mask, const void *data, int data_is, 
	 */

	while (fsnotify_iter_select_report_types(&iter_info)) {

		ret = send_to_group(to_tell, mask, data, data_is, cookie,

				    file_name, &iter_info);

				    file_name->name, &iter_info);



		if (ret && (mask & ALL_FSNOTIFY_PERM_EVENTS))

			goto out;

include/linux/fsnotify.h

+5 −5
Original line number Diff line number Diff line
@@ -27,7 +27,7 @@ static inline int fsnotify_dirent(struct inode *dir, struct dentry *dentry, 
				  __u32 mask)

{

	return fsnotify(dir, mask, d_inode(dentry), FSNOTIFY_EVENT_INODE,

			dentry->d_name.name, 0);

			&dentry->d_name, 0);

}



/* Notify this dentry's parent about a child's events. */
@@ -111,7 +111,7 @@ static inline void fsnotify_move(struct inode *old_dir, struct inode *new_dir, 
	__u32 old_dir_mask = FS_MOVED_FROM;

	__u32 new_dir_mask = FS_MOVED_TO;

	__u32 mask = FS_MOVE_SELF;

	const unsigned char *new_name = moved->d_name.name;

	const struct qstr *new_name = &moved->d_name;



	if (old_dir == new_dir)

		old_dir_mask |= FS_DN_RENAME;
@@ -122,7 +122,7 @@ static inline void fsnotify_move(struct inode *old_dir, struct inode *new_dir, 
		mask |= FS_ISDIR;

	}



	fsnotify(old_dir, old_dir_mask, source, FSNOTIFY_EVENT_INODE, old_name->name,

	fsnotify(old_dir, old_dir_mask, source, FSNOTIFY_EVENT_INODE, old_name,

		 fs_cookie);

	fsnotify(new_dir, new_dir_mask, source, FSNOTIFY_EVENT_INODE, new_name,

		 fs_cookie);
@@ -178,7 +178,7 @@ static inline void fsnotify_nameremove(struct dentry *dentry, int isdir) 
	take_dentry_name_snapshot(&name, dentry);



	fsnotify(d_inode(parent), mask, d_inode(dentry), FSNOTIFY_EVENT_INODE,

		 name.name.name, 0);

		 &name.name, 0);



	release_dentry_name_snapshot(&name);

	dput(parent);
@@ -218,7 +218,7 @@ static inline void fsnotify_link(struct inode *dir, struct inode *inode, struct 
	fsnotify_link_count(inode);

	audit_inode_child(dir, new_dentry, AUDIT_TYPE_CHILD_CREATE);



	fsnotify(dir, FS_CREATE, inode, FSNOTIFY_EVENT_INODE, new_dentry->d_name.name, 0);

	fsnotify(dir, FS_CREATE, inode, FSNOTIFY_EVENT_INODE, &new_dentry->d_name, 0);

}



/*

include/linux/fsnotify_backend.h

+2 −2
Original line number Diff line number Diff line
@@ -350,7 +350,7 @@ struct fsnotify_mark { 


/* main fsnotify call to send events */

extern int fsnotify(struct inode *to_tell, __u32 mask, const void *data, int data_is,

		    const unsigned char *name, u32 cookie);

		    const struct qstr *name, u32 cookie);

extern int __fsnotify_parent(const struct path *path, struct dentry *dentry, __u32 mask);

extern void __fsnotify_inode_delete(struct inode *inode);

extern void __fsnotify_vfsmount_delete(struct vfsmount *mnt);
@@ -505,7 +505,7 @@ static inline void fsnotify_init_event(struct fsnotify_event *event, 
#else



static inline int fsnotify(struct inode *to_tell, __u32 mask, const void *data, int data_is,

			   const unsigned char *name, u32 cookie)

			   const struct qstr *name, u32 cookie)

{

	return 0;

}

CRA Git | Maintained and supported by SUSTech CRA and CCSE