Пример #1
0
static int reiserfs_readdir (struct file * filp, void * dirent, filldir_t filldir)
{
    struct inode *inode = filp->f_dentry->d_inode;
    struct cpu_key pos_key;	/* key of current position in the directory (key of directory entry) */
    INITIALIZE_PATH (path_to_entry);
    struct buffer_head * bh;
    int item_num, entry_num;
    const struct key * rkey;
    struct item_head * ih, tmp_ih;
    int search_res;
    char * local_buf;
    loff_t next_pos;
    char small_buf[32] ; /* avoid kmalloc if we can */
    struct reiserfs_dir_entry de;


    reiserfs_check_lock_depth("readdir") ;

    /* form key for search the next directory entry using f_pos field of
       file structure */
    make_cpu_key (&pos_key, inode, (filp->f_pos) ? (filp->f_pos) : DOT_OFFSET,
		  TYPE_DIRENTRY, 3);
    next_pos = cpu_key_k_offset (&pos_key);

    /*  reiserfs_warning ("reiserfs_readdir 1: f_pos = %Ld\n", filp->f_pos);*/

    while (1) {
    research:
	/* search the directory item, containing entry with specified key */
	search_res = search_by_entry_key (inode->i_sb, &pos_key, &path_to_entry, &de);
	if (search_res == IO_ERROR) {
	    // FIXME: we could just skip part of directory which could
	    // not be read
	    return -EIO;
	}
	entry_num = de.de_entry_num;
	bh = de.de_bh;
	item_num = de.de_item_num;
	ih = de.de_ih;
	store_ih (&tmp_ih, ih);
		
	/* we must have found item, that is item of this directory, */
	RFALSE( COMP_SHORT_KEYS (&(ih->ih_key), &pos_key),
		"vs-9000: found item %h does not match to dir we readdir %k",
		ih, &pos_key);
	RFALSE( item_num > B_NR_ITEMS (bh) - 1,
		"vs-9005 item_num == %d, item amount == %d", 
		item_num, B_NR_ITEMS (bh));
      
	/* and entry must be not more than number of entries in the item */
	RFALSE( I_ENTRY_COUNT (ih) < entry_num,
		"vs-9010: entry number is too big %d (%d)", 
		entry_num, I_ENTRY_COUNT (ih));

	if (search_res == POSITION_FOUND || entry_num < I_ENTRY_COUNT (ih)) {
	    /* go through all entries in the directory item beginning from the entry, that has been found */
	    struct reiserfs_de_head * deh = B_I_DEH (bh, ih) + entry_num;

	    for (; entry_num < I_ENTRY_COUNT (ih); entry_num ++, deh ++) {
		int d_reclen;
		char * d_name;
		off_t d_off;
		ino_t d_ino;

		if (!de_visible (deh))
		    /* it is hidden entry */
		    continue;
		d_reclen = entry_length (bh, ih, entry_num);
		d_name = B_I_DEH_ENTRY_FILE_NAME (bh, ih, deh);
		if (!d_name[d_reclen - 1])
		    d_reclen = strlen (d_name);
	
		if (d_reclen > REISERFS_MAX_NAME_LEN(inode->i_sb->s_blocksize)){
		    /* too big to send back to VFS */
		    continue ;
		}
		d_off = deh_offset (deh);
		filp->f_pos = d_off ;
		d_ino = deh_objectid (deh);
		if (d_reclen <= 32) {
		  local_buf = small_buf ;
		} else {
		    local_buf = kmalloc(d_reclen, GFP_NOFS) ;
		    if (!local_buf) {
			pathrelse (&path_to_entry);
			return -ENOMEM ;
		    }
		    if (item_moved (&tmp_ih, &path_to_entry)) {
			kfree(local_buf) ;
			goto research;
		    }
		}
		// Note, that we copy name to user space via temporary
		// buffer (local_buf) because filldir will block if
		// user space buffer is swapped out. At that time
		// entry can move to somewhere else
		memcpy (local_buf, d_name, d_reclen);
		if (filldir (dirent, local_buf, d_reclen, d_off, d_ino, 
		             DT_UNKNOWN) < 0) {
		    if (local_buf != small_buf) {
			kfree(local_buf) ;
		    }
		    goto end;
		}
		if (local_buf != small_buf) {
		    kfree(local_buf) ;
		}

		// next entry should be looked for with such offset
		next_pos = deh_offset (deh) + 1;

		if (item_moved (&tmp_ih, &path_to_entry)) {
		    goto research;
		}
	    } /* for */
	}

	if (item_num != B_NR_ITEMS (bh) - 1)
	    // end of directory has been reached
	    goto end;

	/* item we went through is last item of node. Using right
	   delimiting key check is it directory end */
	rkey = get_rkey (&path_to_entry, inode->i_sb);
	if (! comp_le_keys (rkey, &MIN_KEY)) {
	    /* set pos_key to key, that is the smallest and greater
	       that key of the last entry in the item */
	    set_cpu_key_k_offset (&pos_key, next_pos);
	    continue;
	}

	if ( COMP_SHORT_KEYS (rkey, &pos_key)) {
	    // end of directory has been reached
	    goto end;
	}
	
	/* directory continues in the right neighboring block */
	set_cpu_key_k_offset (&pos_key, le_key_k_offset (ITEM_VERSION_1, rkey));

    } /* while */


 end:
    // FIXME: ext2_readdir does not reset f_pos
    filp->f_pos = next_pos;
    pathrelse (&path_to_entry);
    reiserfs_check_path(&path_to_entry) ;
    return 0;
}
Пример #2
0
int
reiserfs_readdir(struct vop_readdir_args  /* {
		struct vnode *a_vp;
		struct uio *a_uio;
		struct ucred *a_cred;
		int *a_eofflag;
		int *a_ncookies;
		u_long **a_cookies;
	} */*ap)
{
	int error = 0;
	struct dirent dstdp;
	struct uio *uio = ap->a_uio;

	off_t next_pos;
	struct buf *bp;
	struct item_head *ih;
	struct cpu_key pos_key;
	const struct key *rkey;
	struct reiserfs_node *ip;
	struct reiserfs_dir_entry de;
	INITIALIZE_PATH(path_to_entry);
	int entry_num, item_num, search_res;

	/* The NFS part */
	int ncookies = 0;
	u_long *cookies = NULL;

	/*
	 * Form key for search the next directory entry using f_pos field of
	 * file structure
	 */
	ip = VTOI(ap->a_vp);
	make_cpu_key(&pos_key,
	    ip, uio->uio_offset ? uio->uio_offset : DOT_OFFSET,
	    TYPE_DIRENTRY, 3);
	next_pos = cpu_key_k_offset(&pos_key);

	reiserfs_log(LOG_DEBUG, "listing entries for "
	    "(objectid=%d, dirid=%d)\n",
	    pos_key.on_disk_key.k_objectid, pos_key.on_disk_key.k_dir_id);
	reiserfs_log(LOG_DEBUG, "uio_offset = %jd, uio_resid = %d\n",
	    (intmax_t)uio->uio_offset, uio->uio_resid);

	if (ap->a_ncookies && ap->a_cookies) {
		cookies = (u_long *)malloc(
		    uio->uio_resid / 16 * sizeof(u_long),
		    M_REISERFSCOOKIES, M_WAITOK);
	}

	while (1) {
		//research:
		/*
		 * Search the directory item, containing entry with
		 * specified key
		 */
		reiserfs_log(LOG_DEBUG, "search directory to read\n");
		search_res = search_by_entry_key(ip->i_reiserfs, &pos_key,
		    &path_to_entry, &de);
		if (search_res == IO_ERROR) {
			error = EIO;
			goto out;
		}

		entry_num = de.de_entry_num;
		item_num  = de.de_item_num;
		bp = de.de_bp;
		ih = de.de_ih;

		if (search_res == POSITION_FOUND ||
		    entry_num < I_ENTRY_COUNT(ih)) {
			/*
			 * Go through all entries in the directory item
			 * beginning from the entry, that has been found.
			 */
			struct reiserfs_de_head *deh = B_I_DEH(bp, ih) +
			    entry_num;

			if (ap->a_ncookies == NULL) {
				cookies = NULL;
			} else {
				//ncookies = 
			}

			reiserfs_log(LOG_DEBUG,
			    "walking through directory entries\n");
			for (; entry_num < I_ENTRY_COUNT(ih);
			    entry_num++, deh++) {
				int d_namlen;
				char *d_name;
				off_t d_off;
				ino_t d_ino;

				if (!de_visible(deh)) {
					/* It is hidden entry */
					continue;
				}

				d_namlen = entry_length(bp, ih, entry_num);
				d_name   = B_I_DEH_ENTRY_FILE_NAME(bp, ih, deh);
				if (!d_name[d_namlen - 1])
					d_namlen = strlen(d_name);
				reiserfs_log(LOG_DEBUG, "  - `%s' (len=%d)\n",
				    d_name, d_namlen);

				if (d_namlen > REISERFS_MAX_NAME(
				    ip->i_reiserfs->s_blocksize)) {
					/* Too big to send back to VFS */
					continue;
				}

#if 0
				/* Ignore the .reiserfs_priv entry */
				if (reiserfs_xattrs(ip->i_reiserfs) &&
				    !old_format_only(ip->i_reiserfs) &&
				    filp->f_dentry == ip->i_reiserfs->s_root &&
				    REISERFS_SB(ip->i_reiserfs)->priv_root &&
				    REISERFS_SB(ip->i_reiserfs)->priv_root->d_inode &&
				    deh_objectid(deh) ==
				    le32toh(INODE_PKEY(REISERFS_SB(
				    ip->i_reiserfs)->priv_root->d_inode)->k_objectid)) {
					continue;
				}
#endif

				d_off = deh_offset(deh);
				d_ino = deh_objectid(deh);
				uio->uio_offset = d_off;

				/* Copy to user land */
				dstdp.d_fileno = d_ino;
				dstdp.d_type   = DT_UNKNOWN;
				dstdp.d_namlen = d_namlen;
				dstdp.d_reclen = GENERIC_DIRSIZ(&dstdp);
				bcopy(d_name, dstdp.d_name, dstdp.d_namlen);
				bzero(dstdp.d_name + dstdp.d_namlen,
				    dstdp.d_reclen -
				    offsetof(struct dirent, d_name) -
				    dstdp.d_namlen);

				if (d_namlen > 0) {
					if (dstdp.d_reclen <= uio->uio_resid) {
						reiserfs_log(LOG_DEBUG, "     copying to user land\n");
						error = uiomove(&dstdp,
						    dstdp.d_reclen, uio);
						if (error)
							goto end;
						if (cookies != NULL) {
							cookies[ncookies] =
							    d_off;
							ncookies++;
						}
					} else
						break;
				} else {
					error = EIO;
					break;
				}

				next_pos = deh_offset(deh) + 1;
			}
			reiserfs_log(LOG_DEBUG, "...done\n");
		}

		reiserfs_log(LOG_DEBUG, "checking item num (%d == %d ?)\n",
		    item_num, B_NR_ITEMS(bp) - 1);
		if (item_num != B_NR_ITEMS(bp) - 1) {
			/* End of directory has been reached */
			reiserfs_log(LOG_DEBUG, "end reached\n");
			if (ap->a_eofflag)
				*ap->a_eofflag = 1;
			goto end;
		}

		/*
		 * Item we went through is last item of node. Using right
		 * delimiting key check is it directory end
		 */
		reiserfs_log(LOG_DEBUG, "get right key\n");
		rkey = get_rkey(&path_to_entry, ip->i_reiserfs);
		reiserfs_log(LOG_DEBUG, "right key = (objectid=%d, dirid=%d)\n",
		    rkey->k_objectid, rkey->k_dir_id);

		reiserfs_log(LOG_DEBUG, "compare it to MIN_KEY\n");
		reiserfs_log(LOG_DEBUG, "MIN KEY = (objectid=%d, dirid=%d)\n",
		    MIN_KEY.k_objectid, MIN_KEY.k_dir_id);
		if (comp_le_keys(rkey, &MIN_KEY) == 0) {
			/* Set pos_key to key, that is the smallest and greater
			 * that key of the last entry in the item */
			reiserfs_log(LOG_DEBUG, "continuing on the right\n");
			set_cpu_key_k_offset(&pos_key, next_pos);
			continue;
		}

		reiserfs_log(LOG_DEBUG, "compare it to pos_key\n");
		reiserfs_log(LOG_DEBUG, "pos key = (objectid=%d, dirid=%d)\n",
		    pos_key.on_disk_key.k_objectid,
		    pos_key.on_disk_key.k_dir_id);
		if (COMP_SHORT_KEYS(rkey, &pos_key)) {
			/* End of directory has been reached */
			reiserfs_log(LOG_DEBUG, "end reached (right)\n");
			if (ap->a_eofflag)
				*ap->a_eofflag = 1;
			goto end;
		}

		/* Directory continues in the right neighboring block */
		reiserfs_log(LOG_DEBUG, "continuing with a new offset\n");
		set_cpu_key_k_offset(&pos_key,
		    le_key_k_offset(KEY_FORMAT_3_5, rkey));
		reiserfs_log(LOG_DEBUG,
		    "new pos key = (objectid=%d, dirid=%d)\n",
		    pos_key.on_disk_key.k_objectid,
		    pos_key.on_disk_key.k_dir_id);
	}

end:
	uio->uio_offset = next_pos;
	pathrelse(&path_to_entry);
	reiserfs_check_path(&path_to_entry);
out:
	if (error && cookies != NULL) {
		free(cookies, M_REISERFSCOOKIES);
	} else if (ap->a_ncookies != NULL && ap->a_cookies != NULL) {
		*ap->a_ncookies = ncookies;
		*ap->a_cookies  = cookies;
	}
	return (error);
}
Пример #3
0
static int reiserfs_add_entry(struct reiserfs_transaction_handle *th,
			      struct inode *dir, const char *name, int namelen,
			      struct inode *inode, int visible)
{
	struct cpu_key entry_key;
	struct reiserfs_de_head *deh;
	INITIALIZE_PATH(path);
	struct reiserfs_dir_entry de;
	DECLARE_BITMAP(bit_string, MAX_GENERATION_NUMBER + 1);
	int gen_number;
	char small_buf[32 + DEH_SIZE];	/* 48 bytes now and we avoid kmalloc
					   if we create file with short name */
	char *buffer;
	int buflen, paste_size;
	int retval;

	BUG_ON(!th->t_trans_id);

	/* cannot allow items to be added into a busy deleted directory */
	if (!namelen)
		return -EINVAL;

	if (namelen > REISERFS_MAX_NAME(dir->i_sb->s_blocksize))
		return -ENAMETOOLONG;

	/* each entry has unique key. compose it */
	make_cpu_key(&entry_key, dir,
		     get_third_component(dir->i_sb, name, namelen),
		     TYPE_DIRENTRY, 3);

	/* get memory for composing the entry */
	buflen = DEH_SIZE + ROUND_UP(namelen);
	if (buflen > sizeof(small_buf)) {
		buffer = kmalloc(buflen, GFP_NOFS);
		if (buffer == 0)
			return -ENOMEM;
	} else
		buffer = small_buf;

	paste_size =
	    (get_inode_sd_version(dir) ==
	     STAT_DATA_V1) ? (DEH_SIZE + namelen) : buflen;

	/* fill buffer : directory entry head, name[, dir objectid | , stat data | ,stat data, dir objectid ] */
	deh = (struct reiserfs_de_head *)buffer;
	deh->deh_location = 0;	/* JDM Endian safe if 0 */
	put_deh_offset(deh, cpu_key_k_offset(&entry_key));
	deh->deh_state = 0;	/* JDM Endian safe if 0 */
	/* put key (ino analog) to de */
	deh->deh_dir_id = INODE_PKEY(inode)->k_dir_id;	/* safe: k_dir_id is le */
	deh->deh_objectid = INODE_PKEY(inode)->k_objectid;	/* safe: k_objectid is le */

	/* copy name */
	memcpy((char *)(deh + 1), name, namelen);
	/* padd by 0s to the 4 byte boundary */
	padd_item((char *)(deh + 1), ROUND_UP(namelen), namelen);

	/* entry is ready to be pasted into tree, set 'visibility' and 'stat data in entry' attributes */
	mark_de_without_sd(deh);
	visible ? mark_de_visible(deh) : mark_de_hidden(deh);

	/* find the proper place for the new entry */
	memset(bit_string, 0, sizeof(bit_string));
	de.de_gen_number_bit_string = bit_string;
	retval = reiserfs_find_entry(dir, name, namelen, &path, &de);
	if (retval != NAME_NOT_FOUND) {
		if (buffer != small_buf)
			kfree(buffer);
		pathrelse(&path);

		if (retval == IO_ERROR) {
			return -EIO;
		}

		if (retval != NAME_FOUND) {
			reiserfs_warning(dir->i_sb,
					 "zam-7002:%s: \"reiserfs_find_entry\" "
					 "has returned unexpected value (%d)",
					 __FUNCTION__, retval);
		}

		return -EEXIST;
	}

	gen_number =
	    find_first_zero_bit(bit_string,
				MAX_GENERATION_NUMBER + 1);
	if (gen_number > MAX_GENERATION_NUMBER) {
		/* there is no free generation number */
		reiserfs_warning(dir->i_sb,
				 "reiserfs_add_entry: Congratulations! we have got hash function screwed up");
		if (buffer != small_buf)
			kfree(buffer);
		pathrelse(&path);
		return -EBUSY;
	}
	/* adjust offset of directory enrty */
	put_deh_offset(deh, SET_GENERATION_NUMBER(deh_offset(deh), gen_number));
	set_cpu_key_k_offset(&entry_key, deh_offset(deh));

	/* update max-hash-collisions counter in reiserfs_sb_info */
	PROC_INFO_MAX(th->t_super, max_hash_collisions, gen_number);

	if (gen_number != 0) {	/* we need to re-search for the insertion point */
		if (search_by_entry_key(dir->i_sb, &entry_key, &path, &de) !=
		    NAME_NOT_FOUND) {
			reiserfs_warning(dir->i_sb,
					 "vs-7032: reiserfs_add_entry: "
					 "entry with this key (%K) already exists",
					 &entry_key);

			if (buffer != small_buf)
				kfree(buffer);
			pathrelse(&path);
			return -EBUSY;
		}
	}

	/* perform the insertion of the entry that we have prepared */
	retval =
	    reiserfs_paste_into_item(th, &path, &entry_key, dir, buffer,
				     paste_size);
	if (buffer != small_buf)
		kfree(buffer);
	if (retval) {
		reiserfs_check_path(&path);
		return retval;
	}

	dir->i_size += paste_size;
	dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC;
	if (!S_ISDIR(inode->i_mode) && visible)
		// reiserfs_mkdir or reiserfs_rename will do that by itself
		reiserfs_update_sd(th, dir);

	reiserfs_check_path(&path);
	return 0;
}
Пример #4
0
static int linear_search_in_dir_item(struct cpu_key *key,
				     struct reiserfs_dir_entry *de,
				     const char *name, int namelen)
{
	struct reiserfs_de_head *deh = de->de_deh;
	int retval;
	int i;

	i = de->de_entry_num;

	if (i == I_ENTRY_COUNT(de->de_ih) ||
	    GET_HASH_VALUE(deh_offset(deh + i)) !=
	    GET_HASH_VALUE(cpu_key_k_offset(key))) {
		i--;
	}

	RFALSE(de->de_deh != B_I_DEH(de->de_bh, de->de_ih),
	       "vs-7010: array of entry headers not found");

	deh += i;

	for (; i >= 0; i--, deh--) {
		if (GET_HASH_VALUE(deh_offset(deh)) !=
		    GET_HASH_VALUE(cpu_key_k_offset(key))) {
			// hash value does not match, no need to check whole name
			return NAME_NOT_FOUND;
		}

		/* mark, that this generation number is used */
		if (de->de_gen_number_bit_string)
			set_bit(GET_GENERATION_NUMBER(deh_offset(deh)),
				de->de_gen_number_bit_string);

		// calculate pointer to name and namelen
		de->de_entry_num = i;
		set_de_name_and_namelen(de);

		if ((retval =
		     reiserfs_match(de, name, namelen)) != NAME_NOT_FOUND) {
			// de's de_name, de_namelen, de_recordlen are set. Fill the rest:

			// key of pointed object
			set_de_object_key(de);

			store_de_entry_key(de);

			// retval can be NAME_FOUND or NAME_FOUND_INVISIBLE
			return retval;
		}
	}

	if (GET_GENERATION_NUMBER(le_ih_k_offset(de->de_ih)) == 0)
		/* we have reached left most entry in the node. In common we
		   have to go to the left neighbor, but if generation counter
		   is 0 already, we know for sure, that there is no name with
		   the same hash value */
		// FIXME: this work correctly only because hash value can not
		// be 0. Btw, in case of Yura's hash it is probably possible,
		// so, this is a bug
		return NAME_NOT_FOUND;

	RFALSE(de->de_item_num,
	       "vs-7015: two diritems of the same directory in one node?");

	return GOTO_PREVIOUS_ITEM;
}
Пример #5
0
int reiserfs_readdir_dentry(struct dentry *dentry, void *dirent,
			   filldir_t filldir, loff_t *pos)
{
	struct inode *inode = dentry->d_inode;
	struct cpu_key pos_key;	/* key of current position in the directory (key of directory entry) */
	INITIALIZE_PATH(path_to_entry);
	struct buffer_head *bh;
	int item_num, entry_num;
	const struct reiserfs_key *rkey;
	struct item_head *ih, tmp_ih;
	int search_res;
	char *local_buf;
	loff_t next_pos;
	char small_buf[32];	/* avoid kmalloc if we can */
	struct reiserfs_dir_entry de;
	int ret = 0;

	reiserfs_write_lock(inode->i_sb);

	reiserfs_check_lock_depth(inode->i_sb, "readdir");

	/* form key for search the next directory entry using f_pos field of
	   file structure */
	make_cpu_key(&pos_key, inode, *pos ?: DOT_OFFSET, TYPE_DIRENTRY, 3);
	next_pos = cpu_key_k_offset(&pos_key);

	path_to_entry.reada = PATH_READA;
	while (1) {
	      research:
		/* search the directory item, containing entry with specified key */
		search_res =
		    search_by_entry_key(inode->i_sb, &pos_key, &path_to_entry,
					&de);
		if (search_res == IO_ERROR) {
			// FIXME: we could just skip part of directory which could
			// not be read
			ret = -EIO;
			goto out;
		}
		entry_num = de.de_entry_num;
		bh = de.de_bh;
		item_num = de.de_item_num;
		ih = de.de_ih;
		store_ih(&tmp_ih, ih);

		/* we must have found item, that is item of this directory, */
		RFALSE(COMP_SHORT_KEYS(&(ih->ih_key), &pos_key),
		       "vs-9000: found item %h does not match to dir we readdir %K",
		       ih, &pos_key);
		RFALSE(item_num > B_NR_ITEMS(bh) - 1,
		       "vs-9005 item_num == %d, item amount == %d",
		       item_num, B_NR_ITEMS(bh));

		/* and entry must be not more than number of entries in the item */
		RFALSE(I_ENTRY_COUNT(ih) < entry_num,
		       "vs-9010: entry number is too big %d (%d)",
		       entry_num, I_ENTRY_COUNT(ih));

		if (search_res == POSITION_FOUND
		    || entry_num < I_ENTRY_COUNT(ih)) {
			/* go through all entries in the directory item beginning from the entry, that has been found */
			struct reiserfs_de_head *deh =
			    B_I_DEH(bh, ih) + entry_num;

			for (; entry_num < I_ENTRY_COUNT(ih);
			     entry_num++, deh++) {
				int d_reclen;
				char *d_name;
				off_t d_off;
				ino_t d_ino;
				loff_t cur_pos = deh_offset(deh);

				if (!de_visible(deh))
					/* it is hidden entry */
					continue;
				d_reclen = entry_length(bh, ih, entry_num);
				d_name = B_I_DEH_ENTRY_FILE_NAME(bh, ih, deh);

				if (d_reclen <= 0 ||
				    d_name + d_reclen > bh->b_data + bh->b_size) {
					/* There is corrupted data in entry,
					 * We'd better stop here */
					pathrelse(&path_to_entry);
					ret = -EIO;
					goto out;
				}

				if (!d_name[d_reclen - 1])
					d_reclen = strlen(d_name);

				if (d_reclen >
				    REISERFS_MAX_NAME(inode->i_sb->
						      s_blocksize)) {
					/* too big to send back to VFS */
					continue;
				}

				/* Ignore the .reiserfs_priv entry */
				if (is_privroot_deh(dentry, deh))
					continue;

				d_off = deh_offset(deh);
				*pos = d_off;
				d_ino = deh_objectid(deh);
				if (d_reclen <= 32) {
					local_buf = small_buf;
				} else {
					local_buf = kmalloc(d_reclen,
							    GFP_NOFS);
					if (!local_buf) {
						pathrelse(&path_to_entry);
						ret = -ENOMEM;
						goto out;
					}
					if (item_moved(&tmp_ih, &path_to_entry)) {
						kfree(local_buf);
						goto research;
					}
				}
				// Note, that we copy name to user space via temporary
				// buffer (local_buf) because filldir will block if
				// user space buffer is swapped out. At that time
				// entry can move to somewhere else
				memcpy(local_buf, d_name, d_reclen);

				/*
				 * Since filldir might sleep, we can release
				 * the write lock here for other waiters
				 */
				reiserfs_write_unlock(inode->i_sb);
				if (filldir
				    (dirent, local_buf, d_reclen, d_off, d_ino,
				     DT_UNKNOWN) < 0) {
					reiserfs_write_lock(inode->i_sb);
					if (local_buf != small_buf) {
						kfree(local_buf);
					}
					goto end;
				}
				reiserfs_write_lock(inode->i_sb);
				if (local_buf != small_buf) {
					kfree(local_buf);
				}

				/* deh_offset(deh) may be invalid now. */
				next_pos = cur_pos + 1;

				if (item_moved(&tmp_ih, &path_to_entry)) {
					set_cpu_key_k_offset(&pos_key,
							     next_pos);
					goto research;
				}
			}	/* for */
		}

		if (item_num != B_NR_ITEMS(bh) - 1)
			// end of directory has been reached
			goto end;

		/* item we went through is last item of node. Using right
		   delimiting key check is it directory end */
		rkey = get_rkey(&path_to_entry, inode->i_sb);
		if (!comp_le_keys(rkey, &MIN_KEY)) {
			/* set pos_key to key, that is the smallest and greater
			   that key of the last entry in the item */
			set_cpu_key_k_offset(&pos_key, next_pos);
			continue;
		}

		if (COMP_SHORT_KEYS(rkey, &pos_key)) {
			// end of directory has been reached
			goto end;
		}

		/* directory continues in the right neighboring block */
		set_cpu_key_k_offset(&pos_key,
				     le_key_k_offset(KEY_FORMAT_3_5, rkey));

	}			/* while */

end:
	*pos = next_pos;
	pathrelse(&path_to_entry);
	reiserfs_check_path(&path_to_entry);
out:
	reiserfs_write_unlock(inode->i_sb);
	return ret;
}
Пример #6
0
/*
 * If root directory is empty - we set default - Yura's - hash and warn
 * about it.
 * FIXME: we look for only one name in a directory. If tea and yura both
 * have the same value - we ask user to send report to the mailing list
 */
uint32_t find_hash_out(struct reiserfs_mount *rmp)
{
	int retval;
	struct cpu_key key;
	INITIALIZE_PATH(path);
	struct reiserfs_node *ip;
	struct reiserfs_sb_info *sbi;
	struct reiserfs_dir_entry de;
	uint32_t hash = DEFAULT_HASH;

	get_root_node(rmp, &ip);
	if (!ip)
		return (UNSET_HASH);

	sbi = rmp->rm_reiserfs;

	do {
		uint32_t teahash, r5hash, yurahash;

		reiserfs_log(LOG_DEBUG, "make_cpu_key\n");
		make_cpu_key(&key, ip, ~0, TYPE_DIRENTRY, 3);
		reiserfs_log(LOG_DEBUG, "search_by_entry_key for "
		    "key(objectid=%d,dirid=%d)\n",
		    key.on_disk_key.k_objectid, key.on_disk_key.k_dir_id);
		retval = search_by_entry_key(sbi, &key, &path, &de);
		if (retval == IO_ERROR) {
			pathrelse(&path);
			return (UNSET_HASH);
		}
		if (retval == NAME_NOT_FOUND)
			de.de_entry_num--;

		reiserfs_log(LOG_DEBUG, "name found\n");

		set_de_name_and_namelen(&de);

		if (deh_offset(&(de.de_deh[de.de_entry_num])) == DOT_DOT_OFFSET) {
			/* Allow override in this case */
			if (reiserfs_rupasov_hash(sbi)) {
				hash = YURA_HASH;
			}
			reiserfs_log(LOG_DEBUG,
			    "FS seems to be empty, autodetect "
			    "is using the default hash");
			break;
		}

		r5hash   = GET_HASH_VALUE(r5_hash(de.de_name, de.de_namelen));
		teahash  = GET_HASH_VALUE(keyed_hash(de.de_name,
		    de.de_namelen));
		yurahash = GET_HASH_VALUE(yura_hash(de.de_name, de.de_namelen));
		if (((teahash == r5hash) &&
		    (GET_HASH_VALUE(
		     deh_offset(&(de.de_deh[de.de_entry_num]))) == r5hash)) ||
		    ((teahash == yurahash) &&
		     (yurahash ==
		      GET_HASH_VALUE(
		      deh_offset(&(de.de_deh[de.de_entry_num]))))) ||
		    ((r5hash == yurahash) &&
		     (yurahash ==
		      GET_HASH_VALUE(
		      deh_offset(&(de.de_deh[de.de_entry_num])))))) {
			reiserfs_log(LOG_ERR,
			    "unable to automatically detect hash "
			    "function. Please mount with -o "
			    "hash={tea,rupasov,r5}");
			hash = UNSET_HASH;
			break;
		}

		if (GET_HASH_VALUE(
		    deh_offset(&(de.de_deh[de.de_entry_num]))) == yurahash) {
			reiserfs_log(LOG_DEBUG, "detected YURA hash\n");
			hash = YURA_HASH;
		} else if (GET_HASH_VALUE(
		    deh_offset(&(de.de_deh[de.de_entry_num]))) == teahash) {
			reiserfs_log(LOG_DEBUG, "detected TEA hash\n");
			hash = TEA_HASH;
		} else if (GET_HASH_VALUE(
		    deh_offset(&(de.de_deh[de.de_entry_num]))) == r5hash) {
			reiserfs_log(LOG_DEBUG, "detected R5 hash\n");
			hash = R5_HASH;
		} else {
			reiserfs_log(LOG_WARNING, "unrecognised hash function");
			hash = UNSET_HASH;
		}
	} while (0);

	pathrelse(&path);
	return (hash);
}
Пример #7
0
/*
 * de's de_bh, de_ih, de_deh, de_item_num, de_entry_num are set already
 * Used when hash collisions exist
 */
static int
linear_search_in_dir_item(struct cpu_key *key, struct reiserfs_dir_entry *de,
    const char *name, int namelen)
{
	int i;
	int retval;
	struct reiserfs_de_head * deh = de->de_deh;

	i = de->de_entry_num;

	if (i == I_ENTRY_COUNT(de->de_ih) ||
	    GET_HASH_VALUE(deh_offset(deh + i)) !=
	    GET_HASH_VALUE(cpu_key_k_offset(key))) {
		i--;
	}

	/*RFALSE( de->de_deh != B_I_DEH (de->de_bh, de->de_ih),
	  "vs-7010: array of entry headers not found");*/

	deh += i;

	for (; i >= 0; i--, deh--) {
		if (GET_HASH_VALUE(deh_offset(deh)) !=
		    GET_HASH_VALUE(cpu_key_k_offset(key))) {
			/*
			 * Hash value does not match, no need to check
			 * whole name
			 */
			reiserfs_log(LOG_DEBUG, "name `%s' not found\n", name);
			return (NAME_NOT_FOUND);
		}

		/* Mark that this generation number is used */
		if (de->de_gen_number_bit_string)
			set_bit(GET_GENERATION_NUMBER(deh_offset(deh)),
			    (unsigned long *)de->de_gen_number_bit_string);

		/* Calculate pointer to name and namelen */
		de->de_entry_num = i;
		set_de_name_and_namelen(de);

		if ((retval = reiserfs_match(de, name, namelen)) !=
		    NAME_NOT_FOUND) {
			/*
			 * de's de_name, de_namelen, de_recordlen are set.
			 * Fill the rest:
			 */
			/* key of pointed object */
			set_de_object_key(de);
			store_de_entry_key(de);

			/* retval can be NAME_FOUND or NAME_FOUND_INVISIBLE */
			reiserfs_log(LOG_DEBUG,
			    "reiserfs_match answered `%d'\n",
			    retval);
			return (retval);
		}
	}

	if (GET_GENERATION_NUMBER(le_ih_k_offset(de->de_ih)) == 0)
		/*
		 * We have reached left most entry in the node. In common
		 * we have to go to the left neighbor, but if generation
		 * counter is 0 already, we know for sure, that there is
		 * no name with the same hash value
		 */
		/* FIXME: this work correctly only because hash value can
		 * not be 0. Btw, in case of Yura's hash it is probably
		 * possible, so, this is a bug
		 */
		return (NAME_NOT_FOUND);

	/*RFALSE(de->de_item_num,
	    "vs-7015: two diritems of the same directory in one node?");*/

	return (GOTO_PREVIOUS_ITEM);
}