path: root/fs/ncpfs/dir.c

/*
 *  dir.c
 *
 *  Copyright (C) 1995, 1996 by Volker Lendecke
 *  Modified for big endian by J.F. Chadima and David S. Miller
 *  Modified 1997 Peter Waltenberg, Bill Hawes, David Woodhouse for 2.1 dcache
 *  Modified 1998, 1999 Wolfram Pienkoss for NLS
 *  Modified 1999 Wolfram Pienkoss for directory caching
 *  Modified 2000 Ben Harris, University of Cambridge for NFS NS meta-info
 *
 */


#include <linux/time.h>
#include <linux/errno.h>
#include <linux/stat.h>
#include <linux/kernel.h>
#include <linux/vmalloc.h>
#include <linux/mm.h>
#include <linux/namei.h>
#include <asm/uaccess.h>
#include <asm/byteorder.h>

#include "ncp_fs.h"

static void ncp_read_volume_list(struct file *, void *, filldir_t,
				struct ncp_cache_control *);
static void ncp_do_readdir(struct file *, void *, filldir_t,
				struct ncp_cache_control *);

static int ncp_readdir(struct file *, void *, filldir_t);

static int ncp_create(struct inode *, struct dentry *, umode_t, struct nameidata *);
static struct dentry *ncp_lookup(struct inode *, struct dentry *, struct nameidata *);
static int ncp_unlink(struct inode *, struct dentry *);
static int ncp_mkdir(struct inode *, struct dentry *, umode_t);
static int ncp_rmdir(struct inode *, struct dentry *);
static int ncp_rename(struct inode *, struct dentry *,
	  	      struct inode *, struct dentry *);
static int ncp_mknod(struct inode * dir, struct dentry *dentry,
		     umode_t mode, dev_t rdev);
#if defined(CONFIG_NCPFS_EXTRAS) || defined(CONFIG_NCPFS_NFS_NS)
extern int ncp_symlink(struct inode *, struct dentry *, const char *);
#else
#define ncp_symlink NULL
#endif
		      
const struct file_operations ncp_dir_operations =
{
	.llseek		= generic_file_llseek,
	.read		= generic_read_dir,
	.readdir	= ncp_readdir,
	.unlocked_ioctl	= ncp_ioctl,
#ifdef CONFIG_COMPAT
	.compat_ioctl	= ncp_compat_ioctl,
#endif
};

const struct inode_operations ncp_dir_inode_operations =
{
	.create		= ncp_create,
	.lookup		= ncp_lookup,
	.unlink		= ncp_unlink,
	.symlink	= ncp_symlink,
	.mkdir		= ncp_mkdir,
	.rmdir		= ncp_rmdir,
	.mknod		= ncp_mknod,
	.rename		= ncp_rename,
	.setattr	= ncp_notify_change,
};

/*
 * Dentry operations routines
 */
static int ncp_lookup_validate(struct dentry *, struct nameidata *);
static int ncp_hash_dentry(const struct dentry *, const struct inode *,
		struct qstr *);
static int ncp_compare_dentry(const struct dentry *, const struct inode *,
		const struct dentry *, const struct inode *,
		unsigned int, const char *, const struct qstr *);
static int ncp_delete_dentry(const struct dentry *);

const struct dentry_operations ncp_dentry_operations =
{
	.d_revalidate	= ncp_lookup_validate,
	.d_hash		= ncp_hash_dentry,
	.d_compare	= ncp_compare_dentry,
	.d_delete	= ncp_delete_dentry,
};

#define ncp_namespace(i)	(NCP_SERVER(i)->name_space[NCP_FINFO(i)->volNumber])

static inline int ncp_preserve_entry_case(struct inode *i, __u32 nscreator)
{
#ifdef CONFIG_NCPFS_SMALLDOS
	int ns = ncp_namespace(i);

	if ((ns == NW_NS_DOS)
#ifdef CONFIG_NCPFS_OS2_NS
		|| ((ns == NW_NS_OS2) && (nscreator == NW_NS_DOS))
#endif /* CONFIG_NCPFS_OS2_NS */
	   )
		return 0;
#endif /* CONFIG_NCPFS_SMALLDOS */
	return 1;
}

#define ncp_preserve_case(i)	(ncp_namespace(i) != NW_NS_DOS)

static inline int ncp_case_sensitive(const struct inode *i)
{
#ifdef CONFIG_NCPFS_NFS_NS
	return ncp_namespace(i) == NW_NS_NFS;
#else
	return 0;
#endif /* CONFIG_NCPFS_NFS_NS */
}

/*
 * Note: leave the hash unchanged if the directory
 * is case-sensitive.
 */
static int 
ncp_hash_dentry(const struct dentry *dentry, const struct inode *inode,
		struct qstr *this)
{
	if (!ncp_case_sensitive(inode)) {
		struct super_block *sb = dentry->d_sb;
		struct nls_table *t;
		unsigned long hash;
		int i;

		t = NCP_IO_TABLE(sb);
		hash = init_name_hash();
		for (i=0; i<this->len ; i++)
			hash = partial_name_hash(ncp_tolower(t, this->name[i]),
									hash);
		this->hash = end_name_hash(hash);
	}
	return 0;
}

static int
ncp_compare_dentry(const struct dentry *parent, const struct inode *pinode,
		const struct dentry *dentry, const struct inode *inode,
		unsigned int len, const char *str, const struct qstr *name)
{
	if (len != name->len)
		return 1;

	if (ncp_case_sensitive(pinode))
		return strncmp(str, name->name, len);

	return ncp_strnicmp(NCP_IO_TABLE(pinode->i_sb), str, name->name, len);
}

/*
 * This is the callback from dput() when d_count is going to 0.
 * We use this to unhash dentries with bad inodes.
 * Closing files can be safely postponed until iput() - it's done there anyway.
 */
static int
ncp_delete_dentry(const struct dentry * dentry)