path: root/fs/jffs2/dir.c

/*
 * JFFS2 -- Journalling Flash File System, Version 2.
 *
 * Copyright © 2001-2007 Red Hat, Inc.
 * Copyright © 2004-2010 David Woodhouse <dwmw2@infradead.org>
 *
 * Created by David Woodhouse <dwmw2@infradead.org>
 *
 * For licensing information, see the file 'LICENCE' in this directory.
 *
 */

#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/fs.h>
#include <linux/crc32.h>
#include <linux/jffs2.h>
#include "jffs2_fs_i.h"
#include "jffs2_fs_sb.h"
#include <linux/time.h>
#include "nodelist.h"

static int jffs2_readdir (struct file *, void *, filldir_t);

static int jffs2_create (struct inode *,struct dentry *,int,
			 struct nameidata *);
static struct dentry *jffs2_lookup (struct inode *,struct dentry *,
				    struct nameidata *);
static int jffs2_link (struct dentry *,struct inode *,struct dentry *);
static int jffs2_unlink (struct inode *,struct dentry *);
static int jffs2_symlink (struct inode *,struct dentry *,const char *);
static int jffs2_mkdir (struct inode *,struct dentry *,int);
static int jffs2_rmdir (struct inode *,struct dentry *);
static int jffs2_mknod (struct inode *,struct dentry *,int,dev_t);
static int jffs2_rename (struct inode *, struct dentry *,
			 struct inode *, struct dentry *);

const struct file_operations jffs2_dir_operations =
{
	.read =		generic_read_dir,
	.readdir =	jffs2_readdir,
	.unlocked_ioctl=jffs2_ioctl,
	.fsync =	jffs2_fsync,
	.llseek =	generic_file_llseek,
};


const struct inode_operations jffs2_dir_inode_operations =
{
	.create =	jffs2_create,
	.lookup =	jffs2_lookup,
	.link =		jffs2_link,
	.unlink =	jffs2_unlink,
	.symlink =	jffs2_symlink,
	.mkdir =	jffs2_mkdir,
	.rmdir =	jffs2_rmdir,
	.mknod =	jffs2_mknod,
	.rename =	jffs2_rename,
	.get_acl =	jffs2_get_acl,
	.setattr =	jffs2_setattr,
	.setxattr =	jffs2_setxattr,
	.getxattr =	jffs2_getxattr,
	.listxattr =	jffs2_listxattr,
	.removexattr =	jffs2_removexattr
};

/***********************************************************************/


/* We keep the dirent list sorted in increasing order of name hash,
   and we use the same hash function as the dentries. Makes this
   nice and simple
*/
static struct dentry *jffs2_lookup(struct inode *dir_i, struct dentry *target,
				   struct nameidata *nd)
{
	struct jffs2_inode_info *dir_f;
	struct jffs2_full_dirent *fd = NULL, *fd_list;
	uint32_t ino = 0;
	struct inode *inode = NULL;

	D1(printk(KERN_DEBUG "jffs2_lookup()\n"));

	if (target->d_name.len > JFFS2_MAX_NAME_LEN)
		return ERR_PTR(-ENAMETOOLONG);

	dir_f = JFFS2_INODE_INFO(dir_i);

	mutex_lock(&dir_f->sem);

	/* NB: The 2.2 backport will need to explicitly check for '.' and '..' here */
	for (fd_list = dir_f->dents; fd_list && fd_list->nhash <= target->d_name.hash; fd_list = fd_list->next) {
		if (fd_list->nhash == target->d_name.hash &&
		    (!fd || fd_list->version > fd->version) &&
		    strlen(fd_list->name) == target->d_name.len &&
		    !strncmp(fd_list->name, target->d_name.name, target->d_name.len)) {
			fd = fd_list;
		}
	}
	if (fd)
		ino = fd->ino;
	mutex_unlock(&dir_f->sem);
	if (ino) {
		inode = jffs2_iget(dir_i->i_sb, ino);
		if (IS_ERR(inode))
			printk(KERN_WARNING "iget() failed for ino #%u\n", ino);
	}

	return d_splice_alias(inode, target);
}

/***********************************************************************/


static int jffs2_readdir(struct file *filp, void *dirent, filldir_t filldir)
{
	struct jffs2_inode_info *f;
	struct inode *inode = filp->f_path.dentry->d_inode;
	struct jffs2_full_dirent *fd;
	unsigned long offset, curofs;

	D1(printk(KERN_DEBUG "jffs2_readdir() for dir_i #%lu\n", filp->f_path.dentry->d_inode->i_ino));

	f = JFFS2_INODE_INFO(inode);

	offset = filp->f_pos;

	if (offset == 0) {
		D1(printk(KERN_DEBUG "Dirent 0: \".\", ino #%lu\n", inode->i_ino));
		if (filldir(dirent, ".", 1, 0, inode->i_ino, DT_DIR) < 0)
			goto out;
		offset++;
	}
	if (offset == 1) {
		unsigned long pino = parent_ino(filp->f_path.den