procfs fdinfo extension v2

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370 lines not on this page · raw message

Index: linux-2.6.git/fs/proc/fd.h
===================================================================
@@ -0,0 +1,14 @@
+#ifndef __PROCFS_FD_H__
+#define __PROCFS_FD_H__
+
+#include <linux/fs.h>
+
+extern const struct file_operations proc_fd_operations;
+extern const struct inode_operations proc_fd_inode_operations;
+
+extern const struct file_operations proc_fdinfo_operations;
+extern const struct inode_operations proc_fdinfo_inode_operations;
+
+extern int proc_fd_permission(struct inode *inode, int mask);
+
+#endif /* __PROCFS_FD_H__ */

67 lines not on this page · raw message

Index: linux-2.6.git/fs/proc/fd.c
===================================================================
@@ -6,66 +6,90 @@
 #include <linux/namei.h>
 #include <linux/pid.h>
 #include <linux/security.h>
+#include <linux/file.h>
+#include <linux/seq_file.h>
 
 #include <linux/proc_fs.h>
 
 #include "internal.h"
+#include "fd.h"
 
-#define PROC_FDINFO_MAX 64
+struct proc_fdinfo {
+	loff_t	f_pos;
+	int	f_flags;
+};
 
-static int proc_fd_info(struct inode *inode, struct path *path, char *info)
+static int seq_show(struct seq_file *m, void *v)
+{
+	struct proc_fdinfo *fdinfo = m->private;
+	seq_printf(m, "pos:\t%lli\nflags:\t0%o\n",
+		   (long long)fdinfo->f_pos,
+		   fdinfo->f_flags);
+	return 0;
+}
+
+static int seq_fdinfo_open(struct inode *inode, struct file *file)
 {
-	struct task_struct *task = get_proc_task(inode);
 	struct files_struct *files = NULL;
-	int fd = proc_fd(inode);
-	struct file *file;
+	struct proc_fdinfo *fdinfo = NULL;
+	struct task_struct *task;
+	int ret = -ENOENT;
+
+	fdinfo = kzalloc(sizeof(*fdinfo), GFP_KERNEL);
+	if (!fdinfo)
+		return -ENOMEM;
 
+	task = get_proc_task(inode);
 	if (task) {
 		files = get_files_struct(task);
 		put_task_struct(task);
 	}
 
 	if (files) {
-		/*
-		 * We are not taking a ref to the file structure,
-		 * so we must hold ->file_lock.
-		 */
-		spin_lock(&files->file_lock);
-		file = fcheck_files(files, fd);
+		int fd = proc_fd(inode);
+		struct file *fd_file;
 
-		if (file) {
-			unsigned int f_flags;
-			struct fdtable *fdt;
+		spin_lock(&files->file_lock);
+		fd_file = fcheck_files(files, fd);
+		if (fd_file) {
+			struct fdtable *fdt = files_fdtable(files);
 
-			fdt = files_fdtable(files);
-			f_flags = file->f_flags & ~O_CLOEXEC;
+			fdinfo->f_flags = fd_file->f_flags & ~O_CLOEXEC;
 			if (close_on_exec(fd, fdt))
-				f_flags |= O_CLOEXEC;
-
-			if (path) {
-				*path = file->f_path;
-				path_get(&file->f_path);
-			}
-
-			if (info)
-				snprintf(info, PROC_FDINFO_MAX,
-					 "pos:\t%lli\n"
-					 "flags:\t0%o\n",
-					 (long long)file->f_pos,
-					 f_flags);
-
-			spin_unlock(&files->file_lock);
-			put_files_struct(files);
-			return 0;
+				fdinfo->f_flags |= O_CLOEXEC;
+			ret = 0;
 		}
-
 		spin_unlock(&files->file_lock);
 		put_files_struct(files);
 	}
 
-	return -ENOENT;
+	if (!ret) {
+		ret = single_open(file, seq_show, fdinfo);
+		if (!ret)
+			fdinfo = NULL;
+	}
+
+	kfree(fdinfo);
+	return ret;
 }
 
+static int seq_fdinfo_release(struct inode *inode, struct file *file)
+{
+	struct seq_file *m = file->private_data;
+	struct proc_fdinfo *fdinfo = m->private;
+
+	kfree(fdinfo);
+
+	return single_release(inode, file);
+}
+
+static const struct file_operations proc_fdinfo_file_operations = {
+	.open		= seq_fdinfo_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= seq_fdinfo_release,
+};
+
 static int tid_fd_revalidate(struct dentry *dentry, struct nameidata *nd)
 {
 	struct files_struct *files;

@@ -120,7 +144,31 @@ static const struct dentry_operations ti
 
 static int proc_fd_link(struct dentry *dentry, struct path *path)
 {
-	return proc_fd_info(dentry->d_inode, path, NULL);
+	struct inode *inode = dentry->d_inode;
+	struct task_struct *task = get_proc_task(inode);
+	struct files_struct *files = NULL;
+	int fd = proc_fd(inode);
+	struct file *file;
+	int err = -ENOENT;
+
+	if (task) {
+		files = get_files_struct(task);
+		put_task_struct(task);
+	}
+
+	if (files) {
+		spin_lock(&files->file_lock);
+		file = fcheck_files(files, fd);
+		if (file) {
+			*path = file->f_path;
+			path_get(&file->f_path);
+		}
+		spin_unlock(&files->file_lock);
+		put_files_struct(files);
+		err = 0;
+	}
+
+	return err;
 }
 
 static struct dentry *

@@ -263,22 +311,6 @@ out_no_task:
 	return retval;
 }
 
-static ssize_t proc_fdinfo_read(struct file *file, char __user *buf,
-				      size_t len, loff_t *ppos)
-{
-	char tmp[PROC_FDINFO_MAX];
-	int err = proc_fd_info(file->f_path.dentry->d_inode, NULL, tmp);
-	if (!err)
-		err = simple_read_from_buffer(buf, len, ppos, tmp, strlen(tmp));
-	return err;
-}
-
-static const struct file_operations proc_fdinfo_file_operations = {
-	.open           = nonseekable_open,
-	.read		= proc_fdinfo_read,
-	.llseek		= no_llseek,
-};
-
 static int proc_readfd(struct file *filp, void *dirent, filldir_t filldir)
 {
 	return proc_readfd_common(filp, dirent, filldir, proc_fd_instantiate);

Index: linux-2.6.git/fs/proc/fd.c
===================================================================
@@ -8,12 +8,218 @@
 #include <linux/security.h>
 #include <linux/file.h>
 #include <linux/seq_file.h>
+#include <linux/spinlock.h>
 
 #include <linux/proc_fs.h>
 
 #include "internal.h"
 #include "fd.h"
 
+#ifdef CONFIG_CHECKPOINT_RESTORE
+
+static LIST_HEAD(fdinfo_drivers);
+static DECLARE_RWSEM(fdinfo_drivers_sem);
+
+int proc_register_fdinfo_driver(struct proc_fdinfo_driver *s)
+{
+	struct proc_fdinfo_driver *i;
+	int ret = 0;
+
+	if (!s->ops || !s->probe)
+		return -EINVAL;
+
+	down_write(&fdinfo_drivers_sem);
+	list_for_each_entry(i, &fdinfo_drivers, list) {
+		if (i == s) {
+			WARN_ONCE("Trying reassign fdinfo driver `%s'\n",
+				  i->name);
+			ret = -EINVAL;
+			break;
+		}
+	}
+	if (!ret)
+		list_add(&s->list, &fdinfo_drivers);
+	up_write(&fdinfo_drivers_sem);
+
+	return ret;
+}
+
+void proc_unregister_fdinfo_driver(struct proc_fdinfo_driver *s)
+{
+	struct proc_fdinfo_driver *i;
+
+	down_write(&fdinfo_drivers_sem);
+	list_for_each_entry(i, &fdinfo_drivers, list) {
+		if (i == s) {
+			list_del(&i->list);
+			break;
+		}
+	}
+	up_write(&fdinfo_drivers_sem);
+}
+
+static int prep_fdinfo_driver(struct proc_fdinfo_extra *extra)
+{
+	struct proc_fdinfo_driver *s;
+	int ret = 0;
+
+	down_read(&fdinfo_drivers_sem);
+	list_for_each_entry(s, &fdinfo_drivers, list) {
+		if (s->probe(extra->f_file)) {
+			extra->driver = s;
+			break;
+		}
+	}
+	up_read(&fdinfo_drivers_sem);
+
+	if (extra->driver && extra->driver->priv_size) {
+		extra->priv = kmalloc(extra->driver->priv_size, GFP_KERNEL);
+		if (!extra->priv)
+			ret = -ENOMEM;
+	}
+
+	return ret;
+}
+
+static void *seq_start(struct seq_file *m, loff_t *pos)
+{
+	struct proc_fdinfo_extra *extra = m->private;
+
+	down_read(&fdinfo_drivers_sem);
+	extra->pos = *pos;
+
+	return *pos == 0 ? extra :
+		(extra->driver ? extra->driver->ops->start(m, pos) : NULL);
+}
+
+static void seq_stop(struct seq_file *m, void *v)
+{
+	struct proc_fdinfo_extra *extra = m->private;
+
+	if (extra->driver && extra->pos > 0)
+		extra->driver->ops->stop(m, v);
+	up_read(&fdinfo_drivers_sem);
+}
+
+static void *seq_next(struct seq_file *m, void *p, loff_t *pos)
+{
+	struct proc_fdinfo_extra *extra = m->private;
+	void *v = NULL;
+
+	if (extra->driver) {
+		int ret = 0;
+
+		if (*pos == 0) {
+			v = extra->driver->ops->start(m, pos);
+			if (v) {
+				ret = extra->driver->ops->show(m, v);
+				p = v;
+			} else
+				ret = -1;
+		}
+
+		if (!ret)
+			v = extra->driver->ops->next(m, p, pos);
+	} else
+		++*pos;
+
+	extra->pos = *pos;
+	return v;
+}
+
+static int seq_show(struct seq_file *m, void *v)
+{
+	struct proc_fdinfo_extra *extra = m->private;
+
+	if (extra->driver && extra->pos > 0)
+		return extra->driver->ops->show(m, v);
+
+	seq_printf(m, "pos:\t%lli\nflags:\t0%o\n",
+		   (long long)extra->f_file->f_pos,
+		   extra->f_flags);
+	return 0;
+}
+
+static const struct seq_operations fdinfo_seq_ops = {
+	.start	= seq_start,
+	.next	= seq_next,
+	.stop	= seq_stop,
+	.show	= seq_show,
+};
+
+static int seq_fdinfo_open(struct inode *inode, struct file *file)
+{
+	struct files_struct *files = NULL;
+	struct proc_fdinfo_extra *extra;
+	struct task_struct *task;
+	struct seq_file *m;
+	int ret;
+
+	extra = kzalloc(sizeof(*extra), GFP_KERNEL);
+	if (!extra)
+		return -ENOMEM;
+
+	ret = seq_open(file, &fdinfo_seq_ops);
+	if (!ret) {
+		ret = -ENOENT;
+		m = file->private_data;
+		m->private = extra;
+
+		task = get_proc_task(inode);
+		if (task) {
+			files = get_files_struct(task);
+			put_task_struct(task);
+		}
+
+		if (files) {
+			int fd = proc_fd(inode);
+
+			spin_lock(&files->file_lock);
+			extra->f_file = fcheck_files(files, fd);
+			if (extra->f_file) {
+				struct fdtable *fdt = files_fdtable(files);
+
+				extra->f_flags = extra->f_file->f_flags & ~O_CLOEXEC;
+				if (close_on_exec(fd, fdt))
+					extra->f_flags |= O_CLOEXEC;
+				get_file(extra->f_file);
+			}
+			spin_unlock(&files->file_lock);
+			put_files_struct(files);
+
+			ret = prep_fdinfo_driver(extra);
+		}
+	}
+
+	if (ret) {
+		if (extra->f_file)
+			put_filp(extra->f_file);
+		kfree(extra);
+	}
+	return ret;
+}
+
+static int seq_fdinfo_release(struct inode *inode, struct file *file)
+{
+	struct seq_file *m = file->private_data;
+	struct proc_fdinfo_extra *extra = m->private;
+
+	put_filp(extra->f_file);
+	kfree(extra->priv);
+	kfree(m->private);
+
+	return seq_release(inode, file);
+}
+
+static const struct file_operations proc_fdinfo_file_operations = {
+	.open		= seq_fdinfo_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= seq_fdinfo_release,
+};
+
+#else /* CONFIG_CHECKPOINT_RESTORE */
+
 struct proc_fdinfo {
 	loff_t	f_pos;
 	int	f_flags;

@@ -90,6 +296,8 @@ static const struct file_operations proc
 	.release	= seq_fdinfo_release,
 };
 
+#endif /* CONFIG_CHECKPOINT_RESTORE */
+
 static int tid_fd_revalidate(struct dentry *dentry, struct nameidata *nd)
 {
 	struct files_struct *files;

Index: linux-2.6.git/include/linux/proc_fs.h
===================================================================
@@ -100,6 +100,26 @@ struct vmcore {
 	loff_t offset;
 };
 
+struct seq_operations;
+
+/* fdinfo auxiliary information drivers */
+struct proc_fdinfo_driver {
+	struct list_head		list;
+	const char			*name;
+	const struct seq_operations	*ops;
+	int				(*probe)(struct file *file);
+	size_t				priv_size;
+};
+
+/* auxiliary data allocated per fdinfo reader */
+struct proc_fdinfo_extra {
+	struct proc_fdinfo_driver	*driver;
+	void				*priv;
+	loff_t				pos;
+	struct file			*f_file;
+	unsigned int			f_flags;
+};
+
 #ifdef CONFIG_PROC_FS
 
 extern void proc_root_init(void);

@@ -175,6 +195,11 @@ extern struct proc_dir_entry *proc_net_m
 
 extern struct file *proc_ns_fget(int fd);
 
+#ifdef CONFIG_CHECKPOINT_RESTORE
+extern int proc_register_fdinfo_driver(struct proc_fdinfo_driver *s);
+extern void proc_unregister_fdinfo_driver(struct proc_fdinfo_driver *s);
+#endif /* CONFIG_CHECKPOINT_RESTORE */
+
 #else
 
 #define proc_net_fops_create(net, name, mode, fops)  ({ (void)(mode), NULL; })

@@ -229,6 +254,9 @@ static inline struct file *proc_ns_fget(
 	return ERR_PTR(-EINVAL);
 }
 
+static inline int proc_register_fdinfo_driver(struct proc_fdinfo_driver *s) { return -EINVAL; }
+static inline void proc_unregister_fdinfo_driver(struct proc_fdinfo_driver *s) { }
+
 #endif /* CONFIG_PROC_FS */
 
 #if !defined(CONFIG_PROC_KCORE)

Index: linux-2.6.git/fs/eventfd.c
===================================================================
@@ -19,6 +19,8 @@
 #include <linux/export.h>
 #include <linux/kref.h>
 #include <linux/eventfd.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
 
 struct eventfd_ctx {
 	struct kref kref;

@@ -437,3 +439,56 @@ SYSCALL_DEFINE1(eventfd, unsigned int, c
 	return sys_eventfd2(count, 0);
 }
 
+#if defined(CONFIG_PROC_FS) && defined(CONFIG_CHECKPOINT_RESTORE)
+
+static void *seq_start(struct seq_file *m, loff_t *pos)
+{
+	struct proc_fdinfo_extra *extra = m->private;
+	return *pos == 0 ? extra->f_file : NULL;
+}
+
+static void *seq_next(struct seq_file *m, void *p, loff_t *pos)
+{
+	++*pos;
+	return NULL;
+}
+
+static int seq_show(struct seq_file *m, void *v)
+{
+	struct eventfd_ctx *ctx = ((struct file *)v)->private_data;
+
+	spin_lock_irq(&ctx->wqh.lock);
+	seq_printf(m, "eventfd-count: %16llx\n",
+		   (unsigned long long)ctx->count);
+	spin_unlock_irq(&ctx->wqh.lock);
+
+	return 0;
+}
+
+static void seq_stop(struct seq_file *p, void *v) { }
+
+static const struct seq_operations eventfd_fdinfo_ops = {
+	.start	= seq_start,
+	.next	= seq_next,
+	.stop	= seq_stop,
+	.show	= seq_show,
+};
+
+static int is_eventfd_file(struct file *file)
+{
+	return file->f_op == &eventfd_fops;
+}
+
+static struct proc_fdinfo_driver eventfd_fdinfo = {
+	.name	= "eventfd",
+	.ops	= &eventfd_fdinfo_ops,
+	.probe	= is_eventfd_file,
+};
+
+static int __init eventfd_init(void)
+{
+	return proc_register_fdinfo_driver(&eventfd_fdinfo);
+}
+fs_initcall(eventfd_init);
+
+#endif /* CONFIG_PROC_FS && CONFIG_CHECKPOINT_RESTORE */

Index: linux-2.6.git/fs/eventpoll.c
===================================================================
@@ -37,6 +37,8 @@
 #include <asm/io.h>
 #include <asm/mman.h>
 #include <linux/atomic.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
 
 /*
  * LOCKING:

@@ -1815,6 +1817,83 @@ SYSCALL_DEFINE6(epoll_pwait, int, epfd,
 
 #endif /* HAVE_SET_RESTORE_SIGMASK */
 
+#if defined(CONFIG_PROC_FS) && defined(CONFIG_CHECKPOINT_RESTORE)
+
+struct epitem_fdinfo {
+	struct epoll_event	ev;
+	int			fd;
+};
+
+static struct epitem_fdinfo *
+seq_lookup_fdinfo(struct proc_fdinfo_extra *extra, struct eventpoll *ep, loff_t num)
+{
+	struct epitem_fdinfo *fdinfo = extra->priv;
+	struct epitem *epi = NULL;
+	struct rb_node *rbp;
+
+	mutex_lock(&ep->mtx);
+	for (rbp = rb_first(&ep->rbr); rbp; rbp = rb_next(rbp)) {
+		if (num-- == 0) {
+			epi = rb_entry(rbp, struct epitem, rbn);
+			fdinfo->fd = epi->ffd.fd;
+			fdinfo->ev = epi->event;
+			break;
+		}
+	}
+	mutex_unlock(&ep->mtx);
+
+	return epi ? fdinfo : NULL;
+}
+
+static void *seq_start(struct seq_file *m, loff_t *pos)
+{
+	struct proc_fdinfo_extra *extra = m->private;
+	struct eventpoll *ep = extra->f_file->private_data;
+
+	return seq_lookup_fdinfo(extra, ep, *pos);
+}
+
+static void seq_stop(struct seq_file *m, void *v) { }
+
+static void *seq_next(struct seq_file *m, void *p, loff_t *pos)
+{
+	struct proc_fdinfo_extra *extra = m->private;
+	struct eventpoll *ep = extra->f_file->private_data;
+	++*pos;
+	return (void *)seq_lookup_fdinfo(extra, ep, *pos);
+}
+
+static int seq_show(struct seq_file *m, void *v)
+{
+	struct epitem_fdinfo *fdinfo = v;
+	seq_printf(m, "tfd: %8d events: %8x data: %16llx\n",
+		   fdinfo->fd, fdinfo->ev.events,
+		   (long long)fdinfo->ev.data);
+	return 0;
+}
+
+static const struct seq_operations ep_fdinfo_ops = {
+	.start		= seq_start,
+	.next		= seq_next,
+	.stop		= seq_stop,
+	.show		= seq_show,
+};
+
+static struct proc_fdinfo_driver ep_fdinfo = {
+	.name		= "eventpoll",
+	.ops		= &ep_fdinfo_ops,
+	.probe		= is_file_epoll,
+	.priv_size	= sizeof(struct epitem_fdinfo),
+};
+
+static int __init ep_register_fdinfo_driver(void)
+{
+	return proc_register_fdinfo_driver(&ep_fdinfo);
+}
+#else
+static void ep_register_fdinfo_driver(void) { }
+#endif /* CONFIG_PROC_FS && CONFIG_CHECKPOINT_RESTORE */
+
 static int __init eventpoll_init(void)
 {
 	struct sysinfo si;

@@ -1847,6 +1926,8 @@ static int __init eventpoll_init(void)
 	pwq_cache = kmem_cache_create("eventpoll_pwq",
 			sizeof(struct eppoll_entry), 0, SLAB_PANIC, NULL);
 
+	ep_register_fdinfo_driver();
+
 	return 0;
 }
 fs_initcall(eventpoll_init);

Index: linux-2.6.git/fs/exportfs/expfs.c
===================================================================
@@ -302,6 +302,27 @@ out:
 	return error;
 }
 
+#ifdef CONFIG_CHECKPOINT_RESTORE
+int export_encode_inode_fh(struct inode *inode, struct fid *fid, int *max_len)
+{
+	int len = *max_len;
+	int type = FILEID_INO32_GEN;
+
+	if (len < 2) {
+		*max_len = 2;
+		return 255;
+	}
+
+	len = 2;
+	fid->i32.ino = inode->i_ino;
+	fid->i32.gen = inode->i_generation;
+	*max_len = len;
+
+	return type;
+}
+EXPORT_SYMBOL_GPL(export_encode_inode_fh);
+#endif
+
 /**
  * export_encode_fh - default export_operations->encode_fh function
  * @dentry:  the dentry to encode

Index: linux-2.6.git/include/linux/exportfs.h
===================================================================
@@ -177,6 +177,10 @@ struct export_operations {
 	int (*commit_metadata)(struct inode *inode);
 };
 
+#ifdef CONFIG_CHECKPOINT_RESTORE
+extern int export_encode_inode_fh(struct inode *inode, struct fid *fid, int *max_len);
+#endif
+
 extern int exportfs_encode_fh(struct dentry *dentry, struct fid *fid,
 	int *max_len, int connectable);
 extern struct dentry *exportfs_decode_fh(struct vfsmount *mnt, struct fid *fid,

Index: linux-2.6.git/fs/notify/fanotify/fanotify_user.c
===================================================================
@@ -17,6 +17,7 @@
 #include <asm/ioctls.h>
 
 #include "../../mount.h"
+#include "../fdinfo.h"
 
 #define FANOTIFY_DEFAULT_MAX_EVENTS	16384
 #define FANOTIFY_DEFAULT_MAX_MARKS	8192

@@ -877,6 +878,20 @@ asmlinkage long SyS_fanotify_mark(long f
 SYSCALL_ALIAS(sys_fanotify_mark, SyS_fanotify_mark);
 #endif
 
+#if defined(CONFIG_PROC_FS) && defined(CONFIG_CHECKPOINT_RESTORE)
+int is_file_fanotify(struct file *file)
+{
+	return file->f_op == &fanotify_fops;
+}
+
+static int __init fanotify_register_fdinfo_driver(void)
+{
+	return proc_register_fdinfo_driver(&fanotify_fdinfo);
+}
+#else
+void fanotify_register_fdinfo_driver(void) { }
+#endif /* CONFIG_PROC_FS && CONFIG_CHECKPOINT_RESTORE */
+
 /*
  * fanotify_user_setup - Our initialization function.  Note that we cannot return
  * error because we have compiled-in VFS hooks.  So an (unlikely) failure here

@@ -887,7 +902,7 @@ static int __init fanotify_user_setup(vo
 	fanotify_mark_cache = KMEM_CACHE(fsnotify_mark, SLAB_PANIC);
 	fanotify_response_event_cache = KMEM_CACHE(fanotify_response_event,
 						   SLAB_PANIC);
-
+	fanotify_register_fdinfo_driver();
 	return 0;
 }
 device_initcall(fanotify_user_setup);

218 lines not on this page · raw message

Index: linux-2.6.git/fs/notify/fdinfo.h
===================================================================
@@ -0,0 +1,19 @@
+#ifndef __FSNOTIFY_FDINFO_H__
+#define __FSNOTIFY_FDINFO_H__
+
+#include <linux/errno.h>
+#include <linux/proc_fs.h>
+
+#if defined(CONFIG_PROC_FS) && defined(CONFIG_CHECKPOINT_RESTORE)
+
+#ifdef CONFIG_INOTIFY_USER
+extern struct proc_fdinfo_driver inotify_fdinfo;
+#endif
+
+#ifdef CONFIG_FANOTIFY
+extern struct proc_fdinfo_driver fanotify_fdinfo;
+#endif
+
+#endif
+
+#endif /* __FSNOTIFY_FDINFO_H__ */

Index: linux-2.6.git/fs/notify/inotify/inotify_user.c
===================================================================
@@ -38,8 +38,12 @@
 #include <linux/uaccess.h>
 #include <linux/poll.h>
 #include <linux/wait.h>
+#include <linux/seq_file.h>
+#include <linux/exportfs.h>
+#include <linux/proc_fs.h>
 
 #include "inotify.h"
+#include "../fdinfo.h"
 
 #include <asm/ioctls.h>
 

@@ -827,6 +831,26 @@ out:
 	return ret;
 }
 
+#if defined(CONFIG_PROC_FS) && defined(CONFIG_CHECKPOINT_RESTORE)
+int is_file_inotify(struct file *file)
+{
+	return file->f_op == &inotify_fops;
+}
+
+static int __init inotify_register_fdinfo_driver(void)
+{
+	return proc_register_fdinfo_driver(&inotify_fdinfo);
+}
+
+static void __exit inotify_unregister_fdinfo_driver(void)
+{
+	proc_unregister_fdinfo_driver(&inotify_fdinfo);
+}
+#else
+static int __init inotify_register_fdinfo_driver(void) { return 0; }
+static void __exit inotify_unregister_fdinfo_driver(void) { }
+#endif /* CONFIG_PROC_FS && CONFIG_CHECKPOINT_RESTORE */
+
 /*
  * inotify_user_setup - Our initialization function.  Note that we cannot return
  * error because we have compiled-in VFS hooks.  So an (unlikely) failure here

@@ -862,6 +886,14 @@ static int __init inotify_user_setup(voi
 	inotify_max_user_instances = 128;
 	inotify_max_user_watches = 8192;
 
+	inotify_register_fdinfo_driver();
+
 	return 0;
 }
 module_init(inotify_user_setup);
+
+static void __exit inotify_user_exit(void)
+{
+	inotify_unregister_fdinfo_driver();
+}
+module_exit(inotify_user_exit);