Message-ID: <Pine.LNX.4.64.0712141716180.28689@sbz-30.cs.Helsinki.FI>
Date:	Fri, 14 Dec 2007 17:16:36 +0200 (EET)
From:	Pekka J Enberg <penberg@...helsinki.fi>
To:	alan@...hat.com, viro@...iv.linux.org.uk, hch@...radead.org,
	peterz@...radead.org, linux-kernel@...r.kernel.org,
	linux-fsdevel@...r.kernel.org
Subject: [RFC/PATCH 3/8] revoke: file, inode, and address space operations
 V7

From: Pekka Enberg <penberg@...helsinki.fi>

Add file, inode, and addresspace operations for inodes that represent revoked
files.

Cc: Alan Cox <alan@...hat.com>
Cc: Al Viro <viro@...iv.linux.org.uk>
Cc: Christoph Hellwig <hch@...radead.org>
Cc: Peter Zijlstra <peterz@...radead.org>
Signed-off-by: Pekka Enberg <penberg@...helsinki.fi>
---
 fs/revoked_inode.c |  416 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 416 insertions(+)

Index: 2.6/fs/revoked_inode.c
===================================================================
--- /dev/null	1970-01-01 00:00:00.000000000 +0000
+++ 2.6/fs/revoked_inode.c	2007-12-14 16:40:53.000000000 +0200
@@ -0,0 +1,416 @@
+/*
+ * fs/revoked_inode.c
+ *
+ * Copyright (C) 2007  Pekka Enberg
+ *
+ * Provide stub functions for revoked inodes. Based on fs/bad_inode.c which is
+ *
+ * Copyright (C) 1997  Stephen Tweedie
+ *
+ * This file is released under the GPLv2.
+ */
+
+#include <linux/fs.h>
+#include <linux/module.h>
+#include <linux/stat.h>
+#include <linux/time.h>
+#include <linux/smp_lock.h>
+#include <linux/namei.h>
+#include <linux/poll.h>
+
+static loff_t revoked_file_llseek(struct file *file, loff_t offset, int origin)
+{
+	return -EBADF;
+}
+
+static ssize_t revoked_file_read(struct file *filp, char __user *buf,
+				 size_t size, loff_t *ppos)
+{
+	return -EBADF;
+}
+
+static ssize_t revoked_special_file_read(struct file *filp, char __user *buf,
+					 size_t size, loff_t *ppos)
+{
+	return 0;
+}
+
+static ssize_t revoked_file_write(struct file *filp, const char __user *buf,
+				  size_t siz, loff_t *ppos)
+{
+	return -EBADF;
+}
+
+static ssize_t revoked_file_aio_read(struct kiocb *iocb,
+				     const struct iovec *iov,
+				     unsigned long nr_segs, loff_t pos)
+{
+	return -EBADF;
+}
+
+static ssize_t revoked_file_aio_write(struct kiocb *iocb,
+				      const struct iovec *iov,
+				      unsigned long nr_segs, loff_t pos)
+{
+	return -EBADF;
+}
+
+static int revoked_file_readdir(struct file *filp, void *dirent,
+				filldir_t filldir)
+{
+	return -EBADF;
+}
+
+static unsigned int revoked_file_poll(struct file *filp, poll_table *wait)
+{
+	return POLLERR;
+}
+
+static int revoked_file_ioctl(struct inode *inode, struct file *filp,
+			      unsigned int cmd, unsigned long arg)
+{
+	return -EBADF;
+}
+
+static long revoked_file_unlocked_ioctl(struct file *file, unsigned cmd,
+					unsigned long arg)
+{
+	return -EBADF;
+}
+
+static long revoked_file_compat_ioctl(struct file *file, unsigned int cmd,
+				      unsigned long arg)
+{
+	return -EBADF;
+}
+
+static int revoked_file_mmap(struct file *file, struct vm_area_struct *vma)
+{
+	return -EBADF;
+}
+
+static int revoked_file_open(struct inode *inode, struct file *filp)
+{
+	return -EBADF;
+}
+
+static int revoked_file_flush(struct file *file, fl_owner_t id)
+{
+	return 0;
+}
+
+static int revoked_file_release(struct inode *inode, struct file *filp)
+{
+	return -EBADF;
+}
+
+static int revoked_file_fsync(struct file *file, struct dentry *dentry,
+			      int datasync)
+{
+	return -EBADF;
+}
+
+static int revoked_file_aio_fsync(struct kiocb *iocb, int datasync)
+{
+	return -EBADF;
+}
+
+static int revoked_file_fasync(int fd, struct file *filp, int on)
+{
+	return -EBADF;
+}
+
+static int revoked_file_lock(struct file *file, int cmd, struct file_lock *fl)
+{
+	return -EBADF;
+}
+
+static ssize_t revoked_file_sendpage(struct file *file, struct page *page,
+				     int off, size_t len, loff_t *pos,
+				     int more)
+{
+	return -EBADF;
+}
+
+static unsigned long revoked_file_get_unmapped_area(struct file *file,
+						    unsigned long addr,
+						    unsigned long len,
+						    unsigned long pgoff,
+						    unsigned long flags)
+{
+	return -EBADF;
+}
+
+static int revoked_file_check_flags(int flags)
+{
+	return -EBADF;
+}
+
+static int revoked_file_dir_notify(struct file *file, unsigned long arg)
+{
+	return -EBADF;
+}
+
+static int revoked_file_flock(struct file *filp, int cmd, struct file_lock *fl)
+{
+	return -EBADF;
+}
+
+static ssize_t revoked_file_splice_write(struct pipe_inode_info *pipe,
+					 struct file *out, loff_t *ppos,
+					 size_t len, unsigned int flags)
+{
+	return -EBADF;
+}
+
+static ssize_t revoked_file_splice_read(struct file *in, loff_t *ppos,
+					struct pipe_inode_info *pipe,
+					size_t len, unsigned int flags)
+{
+	return -EBADF;
+}
+
+static const struct file_operations revoked_file_ops = {
+	.llseek = revoked_file_llseek,
+	.read = revoked_file_read,
+	.write = revoked_file_write,
+	.aio_read = revoked_file_aio_read,
+	.aio_write = revoked_file_aio_write,
+	.readdir = revoked_file_readdir,
+	.poll = revoked_file_poll,
+	.ioctl = revoked_file_ioctl,
+	.unlocked_ioctl = revoked_file_unlocked_ioctl,
+	.compat_ioctl = revoked_file_compat_ioctl,
+	.mmap = revoked_file_mmap,
+	.open = revoked_file_open,
+	.flush = revoked_file_flush,
+	.release = revoked_file_release,
+	.fsync = revoked_file_fsync,
+	.aio_fsync = revoked_file_aio_fsync,
+	.fasync = revoked_file_fasync,
+	.lock = revoked_file_lock,
+	.sendpage = revoked_file_sendpage,
+	.get_unmapped_area = revoked_file_get_unmapped_area,
+	.check_flags = revoked_file_check_flags,
+	.dir_notify = revoked_file_dir_notify,
+	.flock = revoked_file_flock,
+	.splice_write = revoked_file_splice_write,
+	.splice_read = revoked_file_splice_read,
+};
+
+static const struct file_operations revoked_special_file_ops = {
+	.llseek = revoked_file_llseek,
+	.read = revoked_special_file_read,
+	.write = revoked_file_write,
+	.aio_read = revoked_file_aio_read,
+	.aio_write = revoked_file_aio_write,
+	.readdir = revoked_file_readdir,
+	.poll = revoked_file_poll,
+	.ioctl = revoked_file_ioctl,
+	.unlocked_ioctl = revoked_file_unlocked_ioctl,
+	.compat_ioctl = revoked_file_compat_ioctl,
+	.mmap = revoked_file_mmap,
+	.open = revoked_file_open,
+	.flush = revoked_file_flush,
+	.release = revoked_file_release,
+	.fsync = revoked_file_fsync,
+	.aio_fsync = revoked_file_aio_fsync,
+	.fasync = revoked_file_fasync,
+	.lock = revoked_file_lock,
+	.sendpage = revoked_file_sendpage,
+	.get_unmapped_area = revoked_file_get_unmapped_area,
+	.check_flags = revoked_file_check_flags,
+	.dir_notify = revoked_file_dir_notify,
+	.flock = revoked_file_flock,
+	.splice_write = revoked_file_splice_write,
+	.splice_read = revoked_file_splice_read,
+};
+
+static int revoked_inode_create(struct inode *dir, struct dentry *dentry,
+				int mode, struct nameidata *nd)
+{
+	return -EBADF;
+}
+
+static struct dentry *revoked_inode_lookup(struct inode *dir,
+					   struct dentry *dentry,
+					   struct nameidata *nd)
+{
+	return ERR_PTR(-EBADF);
+}
+
+static int revoked_inode_link(struct dentry *old_dentry, struct inode *dir,
+			      struct dentry *dentry)
+{
+	return -EBADF;
+}
+
+static int revoked_inode_unlink(struct inode *dir, struct dentry *dentry)
+{
+	return -EBADF;
+}
+
+static int revoked_inode_symlink(struct inode *dir, struct dentry *dentry,
+				 const char *symname)
+{
+	return -EBADF;
+}
+
+static int revoked_inode_mkdir(struct inode *dir, struct dentry *dentry,
+			       int mode)
+{
+	return -EBADF;
+}
+
+static int revoked_inode_rmdir(struct inode *dir, struct dentry *dentry)
+{
+	return -EBADF;
+}
+
+static int revoked_inode_mknod(struct inode *dir, struct dentry *dentry,
+			       int mode, dev_t rdev)
+{
+	return -EBADF;
+}
+
+static int revoked_inode_rename(struct inode *old_dir,
+				struct dentry *old_dentry,
+				struct inode *new_dir,
+				struct dentry *new_dentry)
+{
+	return -EBADF;
+}
+
+static int revoked_inode_readlink(struct dentry *dentry, char __user *buffer,
+				  int buflen)
+{
+	return -EBADF;
+}
+
+static int revoked_inode_permission(struct inode *inode, int mask,
+				    struct nameidata *nd)
+{
+	return -EBADF;
+}
+
+static int revoked_inode_getattr(struct vfsmount *mnt, struct dentry *dentry,
+				 struct kstat *stat)
+{
+	return -EBADF;
+}
+
+static int revoked_inode_setattr(struct dentry *direntry, struct iattr *attrs)
+{
+	return -EBADF;
+}
+
+static int revoked_inode_setxattr(struct dentry *dentry, const char *name,
+				  const void *value, size_t size, int flags)
+{
+	return -EBADF;
+}
+
+static ssize_t revoked_inode_getxattr(struct dentry *dentry, const char *name,
+				      void *buffer, size_t size)
+{
+	return -EBADF;
+}
+
+static ssize_t revoked_inode_listxattr(struct dentry *dentry, char *buffer,
+				       size_t buffer_size)
+{
+	return -EBADF;
+}
+
+static int revoked_inode_removexattr(struct dentry *dentry, const char *name)
+{
+	return -EBADF;
+}
+
+static struct inode_operations revoked_inode_ops = {
+	.create = revoked_inode_create,
+	.lookup = revoked_inode_lookup,
+	.link = revoked_inode_link,
+	.unlink = revoked_inode_unlink,
+	.symlink = revoked_inode_symlink,
+	.mkdir = revoked_inode_mkdir,
+	.rmdir = revoked_inode_rmdir,
+	.mknod = revoked_inode_mknod,
+	.rename = revoked_inode_rename,
+	.readlink = revoked_inode_readlink,
+	/* follow_link must be no-op, otherwise unmounting this inode
+	   won't work */
+	/* put_link returns void */
+	/* truncate returns void */
+	.permission = revoked_inode_permission,
+	.getattr = revoked_inode_getattr,
+	.setattr = revoked_inode_setattr,
+	.setxattr = revoked_inode_setxattr,
+	.getxattr = revoked_inode_getxattr,
+	.listxattr = revoked_inode_listxattr,
+	.removexattr = revoked_inode_removexattr,
+	/* truncate_range returns void */
+};
+
+static int revoked_readpage(struct file *file, struct page *page)
+{
+	return -EIO;
+}
+
+static int revoked_writepage(struct page *page, struct writeback_control *wbc)
+{
+	return -EIO;
+}
+
+static int revoked_prepare_write(struct file *file, struct page *page,
+				 unsigned from, unsigned to)
+{
+	return -EIO;
+}
+
+static int revoked_commit_write(struct file *file, struct page *page,
+				unsigned from, unsigned to)
+{
+	return -EIO;
+}
+
+static ssize_t revoked_direct_IO(int rw, struct kiocb *iocb,
+				 const struct iovec *iov, loff_t offset,
+				 unsigned long nr_segs)
+{
+	return -EIO;
+}
+
+static const struct address_space_operations revoked_aops = {
+	.readpage	= revoked_readpage,
+	.writepage	= revoked_writepage,
+	.prepare_write	= revoked_prepare_write,
+	.commit_write	= revoked_commit_write,
+	.direct_IO	= revoked_direct_IO,
+};
+
+void make_revoked_file(struct inode *inode, struct file *file)
+{
+	if (special_file(inode->i_mode))
+		file->f_op = &revoked_special_file_ops;
+	else
+		file->f_op = &revoked_file_ops;
+
+	file->f_pos = 0;
+}
+
+void make_revoked_inode(struct inode *inode)
+{
+	remove_inode_hash(inode);
+
+	inode->i_atime = inode->i_mtime = inode->i_ctime =
+	    current_fs_time(inode->i_sb);
+	inode->i_op = &revoked_inode_ops;
+
+	if (special_file(inode->i_mode))
+		inode->i_fop = &revoked_special_file_ops;
+	else
+		inode->i_fop = &revoked_file_ops;
+
+	inode->i_mapping->a_ops = &revoked_aops;
+}
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Powered by blists - more mailing lists