コード例 #1
0
ファイル: search.c プロジェクト: mgross029/android_kernel
/* Execute actor for each item (or unit, depending on @through_units_p),
   starting from @coord, right-ward, until either:

   - end of the tree is reached
   - unformatted node is met
   - error occurred
   - @actor returns 0 or less

   Error code, or last actor return value is returned.

   This is used by plugin/dir/hashe_dir.c:reiser4_find_entry() to move through
   sequence of entries with identical keys and alikes.
*/
int reiser4_iterate_tree(reiser4_tree * tree /* tree to scan */ ,
			 coord_t *coord /* coord to start from */ ,
			 lock_handle * lh /* lock handle to start with and to
					   * update along the way */ ,
			 tree_iterate_actor_t actor /* function to call on each
						     * item/unit */ ,
			 void *arg /* argument to pass to @actor */ ,
			 znode_lock_mode mode /* lock mode on scanned nodes */ ,
			 int through_units_p /* call @actor on each item or on
					      *	each unit */ )
{
	int result;

	assert("nikita-1143", tree != NULL);
	assert("nikita-1145", coord != NULL);
	assert("nikita-1146", lh != NULL);
	assert("nikita-1147", actor != NULL);

	result = zload(coord->node);
	coord_clear_iplug(coord);
	if (result != 0)
		return result;
	if (!coord_is_existing_unit(coord)) {
		zrelse(coord->node);
		return -ENOENT;
	}
	while ((result = actor(tree, coord, lh, arg)) > 0) {
		/* move further  */
		if ((through_units_p && coord_next_unit(coord)) ||
		    (!through_units_p && coord_next_item(coord))) {
			do {
				lock_handle couple;

				/* move to the next node  */
				init_lh(&couple);
				result =
				    reiser4_get_right_neighbor(&couple,
							       coord->node,
							       (int)mode,
							       GN_CAN_USE_UPPER_LEVELS);
				zrelse(coord->node);
				if (result == 0) {

					result = zload(couple.node);
					if (result != 0) {
						done_lh(&couple);
						return result;
					}

					coord_init_first_unit(coord,
							      couple.node);
					done_lh(lh);
					move_lh(lh, &couple);
				} else
					return result;
			} while (node_is_empty(coord->node));
		}

		assert("nikita-1149", coord_is_existing_unit(coord));
	}
	zrelse(coord->node);
	return result;
}
コード例 #2
0
/**
 * reiser4_replace_extent - replace extent and paste 1 or 2 after it
 * @un_extent: coordinate of extent to be overwritten
 * @lh: need better comment
 * @key: need better comment
 * @exts_to_add: data prepared for insertion into tree
 * @replace: need better comment
 * @flags: need better comment
 * @return_insert_position: need better comment
 *
 * Overwrites one extent, pastes 1 or 2 more ones after overwritten one.  If
 * @return_inserted_position is 1 - @un_extent and @lh are returned set to
 * first of newly inserted units, if it is 0 - @un_extent and @lh are returned
 * set to extent which was overwritten.
 */
int reiser4_replace_extent(struct replace_handle *h,
                           int return_inserted_position)
{
    int result;
    znode *orig_znode;
    /*ON_DEBUG(reiser4_extent orig_ext);*/	/* this is for debugging */

    assert("vs-990", coord_is_existing_unit(h->coord));
    assert("vs-1375", znode_is_write_locked(h->coord->node));
    assert("vs-1426", extent_get_width(&h->overwrite) != 0);
    assert("vs-1427", extent_get_width(&h->new_extents[0]) != 0);
    assert("vs-1427", ergo(h->nr_new_extents == 2,
                           extent_get_width(&h->new_extents[1]) != 0));

    /* compose structure for paste */
    init_new_extent(&h->item, &h->new_extents[0], h->nr_new_extents);

    coord_dup(&h->coord_after, h->coord);
    init_lh(&h->lh_after);
    copy_lh(&h->lh_after, h->lh);
    reiser4_tap_init(&h->watch, &h->coord_after, &h->lh_after, ZNODE_WRITE_LOCK);
    reiser4_tap_monitor(&h->watch);

    ON_DEBUG(h->orig_ext = *extent_by_coord(h->coord));
    orig_znode = h->coord->node;

#if REISER4_DEBUG
    /* make sure that key is set properly */
    unit_key_by_coord(h->coord, &h->tmp);
    set_key_offset(&h->tmp,
                   get_key_offset(&h->tmp) +
                   extent_get_width(&h->overwrite) * current_blocksize);
    assert("vs-1080", keyeq(&h->tmp, &h->paste_key));
#endif

    /* set insert point after unit to be replaced */
    h->coord->between = AFTER_UNIT;

    result = insert_into_item(h->coord, return_inserted_position ? h->lh : NULL,
                              &h->paste_key, &h->item, h->flags);
    if (!result) {
        /* now we have to replace the unit after which new units were
           inserted. Its position is tracked by @watch */
        reiser4_extent *ext;
        znode *node;

        node = h->coord_after.node;
        if (node != orig_znode) {
            coord_clear_iplug(&h->coord_after);
            result = zload(node);
        }

        if (likely(!result)) {
            ext = extent_by_coord(&h->coord_after);

            assert("vs-987", znode_is_loaded(node));
            assert("vs-988", !memcmp(ext, &h->orig_ext, sizeof(*ext)));

            /* overwrite extent unit */
            memcpy(ext, &h->overwrite, sizeof(reiser4_extent));
            znode_make_dirty(node);

            if (node != orig_znode)
                zrelse(node);

            if (return_inserted_position == 0) {
                /* coord and lh are to be set to overwritten
                   extent */
                assert("vs-1662",
                       WITH_DATA(node, !memcmp(&h->overwrite,
                                               extent_by_coord(
                                                   &h->coord_after),
                                               sizeof(reiser4_extent))));

                *h->coord = h->coord_after;
                done_lh(h->lh);
                copy_lh(h->lh, &h->lh_after);
            } else {
                /* h->coord and h->lh are to be set to first of
                   inserted units */
                assert("vs-1663",
                       WITH_DATA(h->coord->node,
                                 !memcmp(&h->new_extents[0],
                                         extent_by_coord(h->coord),
                                         sizeof(reiser4_extent))));
                assert("vs-1664", h->lh->node == h->coord->node);
            }
        }
    }
    reiser4_tap_done(&h->watch);

    return result;
}