kill ->dir_notify()

Remove the hopelessly misguided ->dir_notify().  The only instance (cifs)
has been broken by design from the very beginning; the objects it creates
are never destroyed, keep references to struct file they can outlive, nothing
that could possibly evict them exists on close(2) path *and* no locking
whatsoever is done to prevent races with close(), should the previous, er,
deficiencies someday be dealt with.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Documentation/filesystems/Locking

@@ -394,7 +394,6 @@ prototypes:
 	unsigned long (*get_unmapped_area)(struct file *, unsigned long,
 			unsigned long, unsigned long, unsigned long);
 	int (*check_flags)(int);
-	int (*dir_notify)(struct file *, unsigned long);
 };
 
 locking rules:
@@ -424,7 +423,6 @@ sendfile:		no
 sendpage:		no
 get_unmapped_area:	no
 check_flags:		no
-dir_notify:		no
 
 ->llseek() locking has moved from llseek to the individual llseek
 implementations.  If your fs is not using generic_file_llseek, you

Documentation/filesystems/vfs.txt

@@ -733,7 +733,6 @@ struct file_operations {
 	ssize_t (*sendpage) (struct file *, struct page *, int, size_t, loff_t *, int);
 	unsigned long (*get_unmapped_area)(struct file *, unsigned long, unsigned long, unsigned long, unsigned long);
 	int (*check_flags)(int);
-	int (*dir_notify)(struct file *filp, unsigned long arg);
 	int (*flock) (struct file *, int, struct file_lock *);
 	ssize_t (*splice_write)(struct pipe_inode_info *, struct file *, size_t, unsigned int);
 	ssize_t (*splice_read)(struct file *, struct pipe_inode_info *, size_t, unsigned int);
@@ -800,8 +799,6 @@ otherwise noted.
 
   check_flags: called by the fcntl(2) system call for F_SETFL command
 
-  dir_notify: called by the fcntl(2) system call for F_NOTIFY command
-
   flock: called by the flock(2) system call
 
   splice_write: called by the VFS to splice data from a pipe to a file. This

fs/bad_inode.c

@@ -132,11 +132,6 @@ static int bad_file_check_flags(int flags)
 	return -EIO;
 }
 
-static int bad_file_dir_notify(struct file *file, unsigned long arg)
-{
-	return -EIO;
-}
-
 static int bad_file_flock(struct file *filp, int cmd, struct file_lock *fl)
 {
 	return -EIO;
@@ -179,7 +174,6 @@ static const struct file_operations bad_file_ops =
 	.sendpage	= bad_file_sendpage,
 	.get_unmapped_area = bad_file_get_unmapped_area,
 	.check_flags	= bad_file_check_flags,
-	.dir_notify	= bad_file_dir_notify,
 	.flock		= bad_file_flock,
 	.splice_write	= bad_file_splice_write,
 	.splice_read	= bad_file_splice_read,

fs/cifs/Makefile

@@ -5,7 +5,7 @@ obj-$(CONFIG_CIFS) += cifs.o
 
 cifs-y := cifsfs.o cifssmb.o cifs_debug.o connect.o dir.o file.o inode.o \
 	  link.o misc.o netmisc.o smbdes.o smbencrypt.o transport.o asn1.o \
-	  md4.o md5.o cifs_unicode.o nterr.o xattr.o cifsencrypt.o fcntl.o \
+	  md4.o md5.o cifs_unicode.o nterr.o xattr.o cifsencrypt.o \
 	  readdir.o ioctl.o sess.o export.o cifsacl.o
 
 cifs-$(CONFIG_CIFS_UPCALL) += cifs_spnego.o

fs/cifs/cifsfs.c

@@ -747,7 +747,6 @@ const struct file_operations cifs_file_ops = {
 #endif /* CONFIG_CIFS_POSIX */
 
 #ifdef CONFIG_CIFS_EXPERIMENTAL
-	.dir_notify = cifs_dir_notify,
 	.setlease = cifs_setlease,
 #endif /* CONFIG_CIFS_EXPERIMENTAL */
 };
@@ -768,7 +767,6 @@ const struct file_operations cifs_file_direct_ops = {
 #endif /* CONFIG_CIFS_POSIX */
 	.llseek = cifs_llseek,
 #ifdef CONFIG_CIFS_EXPERIMENTAL
-	.dir_notify = cifs_dir_notify,
 	.setlease = cifs_setlease,
 #endif /* CONFIG_CIFS_EXPERIMENTAL */
 };
@@ -789,7 +787,6 @@ const struct file_operations cifs_file_nobrl_ops = {
 #endif /* CONFIG_CIFS_POSIX */
 
 #ifdef CONFIG_CIFS_EXPERIMENTAL
-	.dir_notify = cifs_dir_notify,
 	.setlease = cifs_setlease,
 #endif /* CONFIG_CIFS_EXPERIMENTAL */
 };
@@ -809,7 +806,6 @@ const struct file_operations cifs_file_direct_nobrl_ops = {
 #endif /* CONFIG_CIFS_POSIX */
 	.llseek = cifs_llseek,
 #ifdef CONFIG_CIFS_EXPERIMENTAL
-	.dir_notify = cifs_dir_notify,
 	.setlease = cifs_setlease,
 #endif /* CONFIG_CIFS_EXPERIMENTAL */
 };
@@ -818,9 +814,6 @@ const struct file_operations cifs_dir_ops = {
 	.readdir = cifs_readdir,
 	.release = cifs_closedir,
 	.read    = generic_read_dir,
-#ifdef CONFIG_CIFS_EXPERIMENTAL
-	.dir_notify = cifs_dir_notify,
-#endif /* CONFIG_CIFS_EXPERIMENTAL */
 	.unlocked_ioctl  = cifs_ioctl,
 	.llseek = generic_file_llseek,
 };

fs/cifs/cifsfs.h

@@ -76,7 +76,6 @@ extern int cifs_file_mmap(struct file * , struct vm_area_struct *);
 extern const struct file_operations cifs_dir_ops;
 extern int cifs_dir_open(struct inode *inode, struct file *file);
 extern int cifs_readdir(struct file *file, void *direntry, filldir_t filldir);
-extern int cifs_dir_notify(struct file *, unsigned long arg);
 
 /* Functions related to dir entries */
 extern struct dentry_operations cifs_dentry_ops;

fs/cifs/fcntl.c

-/*
- *   fs/cifs/fcntl.c
- *
- *   vfs operations that deal with the file control API
- *
- *   Copyright (C) International Business Machines  Corp., 2003,2004
- *   Author(s): Steve French (sfrench@us.ibm.com)
- *
- *   This library is free software; you can redistribute it and/or modify
- *   it under the terms of the GNU Lesser General Public License as published
- *   by the Free Software Foundation; either version 2.1 of the License, or
- *   (at your option) any later version.
- *
- *   This library is distributed in the hope that it will be useful,
- *   but WITHOUT ANY WARRANTY; without even the implied warranty of
- *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
- *   the GNU Lesser General Public License for more details.
- *
- *   You should have received a copy of the GNU Lesser General Public License
- *   along with this library; if not, write to the Free Software
- *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
- */
-#include <linux/fs.h>
-#include <linux/stat.h>
-#include <linux/fcntl.h>
-#include "cifsglob.h"
-#include "cifsproto.h"
-#include "cifs_unicode.h"
-#include "cifs_debug.h"
-#include "cifsfs.h"
-
-static __u32 convert_to_cifs_notify_flags(unsigned long fcntl_notify_flags)
-{
-	__u32 cifs_ntfy_flags = 0;
-
-	/* No way on Linux VFS to ask to monitor xattr
-	changes (and no stream support either */
-	if (fcntl_notify_flags & DN_ACCESS)
-		cifs_ntfy_flags |= FILE_NOTIFY_CHANGE_LAST_ACCESS;
-	if (fcntl_notify_flags & DN_MODIFY) {
-		/* What does this mean on directories? */
-		cifs_ntfy_flags |= FILE_NOTIFY_CHANGE_LAST_WRITE |
-			FILE_NOTIFY_CHANGE_SIZE;
-	}
-	if (fcntl_notify_flags & DN_CREATE) {
-		cifs_ntfy_flags |= FILE_NOTIFY_CHANGE_CREATION |
-			FILE_NOTIFY_CHANGE_LAST_WRITE;
-	}
-	if (fcntl_notify_flags & DN_DELETE)
-		cifs_ntfy_flags |= FILE_NOTIFY_CHANGE_LAST_WRITE;
-	if (fcntl_notify_flags & DN_RENAME) {
-		/* BB review this - checking various server behaviors */
-		cifs_ntfy_flags |= FILE_NOTIFY_CHANGE_DIR_NAME |
-			FILE_NOTIFY_CHANGE_FILE_NAME;
-	}
-	if (fcntl_notify_flags & DN_ATTRIB) {
-		cifs_ntfy_flags |= FILE_NOTIFY_CHANGE_SECURITY |
-			FILE_NOTIFY_CHANGE_ATTRIBUTES;
-	}
-/*	if (fcntl_notify_flags & DN_MULTISHOT) {
-		cifs_ntfy_flags |= ;
-	} */ /* BB fixme - not sure how to handle this with CIFS yet */
-
-	return cifs_ntfy_flags;
-}
-
-int cifs_dir_notify(struct file *file, unsigned long arg)
-{
-	int xid;
-	int rc = -EINVAL;
-	int oplock = 0;
-	struct cifs_sb_info *cifs_sb;
-	struct cifsTconInfo *pTcon;
-	char *full_path = NULL;
-	__u32 filter = FILE_NOTIFY_CHANGE_NAME | FILE_NOTIFY_CHANGE_ATTRIBUTES;
-	__u16 netfid;
-
-	if (experimEnabled == 0)
-		return 0;
-
-	xid = GetXid();
-	cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
-	pTcon = cifs_sb->tcon;
-
-	full_path = build_path_from_dentry(file->f_path.dentry);
-
-	if (full_path == NULL) {
-		rc = -ENOMEM;
-	} else {
-		cFYI(1, ("dir notify on file %s Arg 0x%lx", full_path, arg));
-		rc = CIFSSMBOpen(xid, pTcon, full_path, FILE_OPEN,
-			GENERIC_READ | SYNCHRONIZE, 0 /* create options */,
-			&netfid, &oplock, NULL, cifs_sb->local_nls,
-			cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
-		/* BB fixme - add this handle to a notify handle list */
-		if (rc) {
-			cFYI(1, ("Could not open directory for notify"));
-		} else {
-			filter = convert_to_cifs_notify_flags(arg);
-			if (filter != 0) {
-				rc = CIFSSMBNotify(xid, pTcon,
-					0 /* no subdirs */, netfid,
-					filter, file, arg & DN_MULTISHOT,
-					cifs_sb->local_nls);
-			} else {
-				rc = -EINVAL;
-			}
-			/* BB add code to close file eventually (at unmount
-			it would close automatically but may be a way
-			to do it easily when inode freed or when
-			notify info is cleared/changed */
-			cFYI(1, ("notify rc %d", rc));
-		}
-	}
-
-	FreeXid(xid);
-	return rc;
-}

fs/dnotify.c

@@ -115,9 +115,6 @@ int fcntl_dirnotify(int fd, struct file *filp, unsigned long arg)
 	dn->dn_next = inode->i_dnotify;
 	inode->i_dnotify = dn;
 	spin_unlock(&inode->i_lock);
-
-	if (filp->f_op && filp->f_op->dir_notify)
-		return filp->f_op->dir_notify(filp, arg);
 	return 0;
 
 out_free:

include/linux/fs.h

@@ -1309,7 +1309,6 @@ struct file_operations {
 	ssize_t (*sendpage) (struct file *, struct page *, int, size_t, loff_t *, int);
 	unsigned long (*get_unmapped_area)(struct file *, unsigned long, unsigned long, unsigned long, unsigned long);
 	int (*check_flags)(int);
-	int (*dir_notify)(struct file *filp, unsigned long arg);
 	int (*flock) (struct file *, int, struct file_lock *);
 	ssize_t (*splice_write)(struct pipe_inode_info *, struct file *, loff_t *, size_t, unsigned int);
 	ssize_t (*splice_read)(struct file *, loff_t *, struct pipe_inode_info *, size_t, unsigned int);